822 results
Search Results
2. IMPURITIES DURING ICRF HEATING EXPERIMENT IN JFT-2
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Paper presented by and K. Odajima
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Materials science ,Impurity ,Condensed Matter::Superconductivity ,Nuclear engineering ,Condensed Matter::Strongly Correlated Electrons ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,Heating efficiency - Abstract
Impurities during the ICRF heating experiment in JFT-2 are presented. One atempt to reduce impurities and to improve a heating efficiency is shown.
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- 1982
3. ICRF HEATING EXPERIMENT IN JFT-2
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Paper presented by and K. Odajima
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High energy ,Deuterium ,Chemistry ,RF power amplifier ,Analytical chemistry ,Ion temperature ,Plasma ,Electron ,Atomic physics ,Absorption (electromagnetic radiation) - Abstract
Up to 600 kW of ICRF power is coupled to plasma with the small area antennae (460 cm 2 ). Around P net = 500 kW, ion temperature increases from 0.4 to 0.8 keV, that of electron 0.6 to 0.9 keV, and increase of β is 0.35 ~ 0.4. Clear dependence on the n H /n D is not observed. Deuterium high energy tail is observed, which indicates a direct absorption of rf power by deuterium.
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- 1982
4. OPERATION OF GROUND TRANSPORTATION SYSTEMS: TRAFFIC CONTROL OF SUBWAYS
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Survey Paper and Jean-Michel Lassalle
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Transport engineering ,Engineering ,Disturbance (geology) ,business.industry ,Control (management) ,Ticket ,Public address system ,Ground transportation ,business ,Viewpoints ,Control room ,Vulnerability (computing) - Abstract
This survey paper indicates various aspects of traffic control of subways: The general concepts of the carrier (transportation supply, disturbance, vulnerability, transportation costs and human concepts) and some ideas to organize the operation. For illustration, many examples are given in the following fields: — automatic driving and driver monitoring devices; — central control room; — ticket issuing and checking; — public address systems. The conclusion points out that the effectiveness of any system is conditional on a balanced consideration of all the various viewpoints: technical, economic and human.
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- 1984
5. TECHNICAL AND DESIGN ASPECT OF JFT-2 ICRF HEATING
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Paper presented by and K. Odajima
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Coupling ,Engineering ,Optics ,business.industry ,RF power amplifier ,Electrical engineering ,business ,Radiation resistance - Abstract
Up to 820 kW of rf power is delivered to the only 460 cm 2 area of antennae with the radiation resistance about 1 ω. The radiation resistance agrees well with the strong damping model proposed by J. Adam. A plan for ridge wave guide coupling in JFT-2M is also shown.
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- 1982
6. Antioxidant potential of flavonoid glycosides from Manniophyton fulvum Müll. (Euphorbiaceae): Identification and molecular modeling
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Smith B. Babiaka, Rene Nia, Kennedy O. Abuga, James A. Mbah, Vincent de Paul N. Nziko, Dietrich H. Paper, and Fidele Ntie-Kang
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Antioxidant and anti-inflammatory ,Flavonoid glycosides ,Manniophyton fulvum ,HERG ,Molecular modeling ,Science - Abstract
Chemical investigation of the leaves of Manniophyton fulvum led to the isolation of seven flavonoid glycosides: myricetin-3-O-β-Dd-rhamnoside (1), kaempferol-3-O-β-d-rhamnoside (2), quercetin-3-O-β-d-glucoside (3), quercetin-3-O-β-d-rhamnoside (4), quercetin-3-O-β-d-galactoside (5), rutin (6) and quercetin (7). The structures of the compounds were established by spectroscopic analyses as well as by comparison with published data. Some of the compounds showed strong antioxidant activity which validates the traditional use of the plant. An attempted correlation between the computed HOMO-LUMO energies and the measured antioxidant activities was established. We have also estimated the cardiotoxicity of the compounds by calculating the predicted logarithm of the human Ether-`a-go-go Related Gene (loghERG) using the QikProp program. These purified flavonoids are new potential lead compounds for the development of antioxidant drugs.
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- 2020
- Full Text
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7. Association of food insecurity with suicidal ideation and suicide attempts in adults aged ≥50 years from low- and middle-income countries
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Lee Smith, Jae Il Shin, Christina Carmichael, Louis Jacob, Karel Kostev, Igor Grabovac, Yvonne Barnett, Laurie Butler, Rosie K. Lindsay, Damiano Pizzol, Nicola Veronese, Pinar Soysal, Ai Koyanagi, Smith, Lee, Shin, Jae Il, Carmichael, Christina, Jacob, Loui, Kostev, Karel, Grabovac, Igor, Barnett, Yvonne, Butler, Laurie, Lindsay, Rosie K, Pizzol, Damiano, Veronese, Nicola, Soysal, Pinar, Koyanagi, Ai, SOYSAL, PINAR, Anglia Ruskin University (ARU), Yonsei University, Université de Versailles Saint-Quentin-en-Yvelines - UFR Sciences de la santé Simone Veil (UVSQ Santé), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), IQVIA, Medizinische Universität Wien = Medical University of Vienna, Università degli studi di Palermo - University of Palermo, ICREA Infection Biology Laboratory (Department of Experimental and Health Sciences), Universitat Pompeu Fabra [Barcelona] (UPF), National Institute on Aging, NIA: OGHA 04034785, R01-AG034479, R21-AG034263, Y1-AG-1005–01, YA1323–08-CN-0020, This paper uses data from WHO's Study on Global Aging and Adult Health (SAGE). SAGE is supported by the U.S. National Institute on Aging through Interagency Agreements OGHA 04034785 , YA1323–08-CN-0020 , Y1-AG-1005–01 and through research grants R01-AG034479 and R21-AG034263 ., and European Project: 671500,H2020,H2020-FETHPC-2014,SAGE(2015)
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Male ,Low- and middle-income countries ,Suicide, Attempted ,Suicidal Ideation ,Psychiatry and Mental health ,Clinical Psychology ,Food Insecurity ,Cross-Sectional Studies ,Association of food insecurity with suicidal ideation and suicide attempts in adults aged ≥50 years from low- and middle-income countries.-, Journal of affective disorders, 2022 ,Risk Factors ,Older adults ,[SDV.MHEP.PSM]Life Sciences [q-bio]/Human health and pathology/Psychiatrics and mental health ,Food insecurity, Low- and middle-income countries, Older adults, Suicidal ideation, Suicide attempts ,Humans ,Female ,Developing Countries ,Suicide attempts ,Aged - Abstract
Background-\ud \ud The aim of the present study was to investigate associations between food insecurity with suicidal ideation and suicide attempts in adults aged ≥50 years from six low- and middle-income countries (LMICs).\ud \ud Methods-\ud \ud Cross-sectional, community-based data from the World Health Organisation's Study on Global Aging and Adult Health were analyzed. Self-reported information on past 12-month suicidal ideation and suicide attempts was collected. Past 12-month food insecurity was assessed with two questions on frequency of eating less and hunger due to lack of food. Multivariable logistic regression analysis was conducted to assess the association between food insecurity and suicidal ideation or suicide attempts.\ud \ud Results-\ud \ud The final analytical sample included 34,129 individuals aged ≥50 years [mean (SD) age 62.4 (16.0) years; 52.1% females]. Compared to no food insecurity, severe food insecurity was associated with a significant 2.78 (95%CI = 1.73–4.45) times higher odds for suicidal ideation, while moderate and severe food insecurity were associated with 2.59 (95%CI = 1.35–4.97) and 5.15 (95%CI = 2.52–10.53) times higher odds for suicide attempts, respectively.\ud \ud Limitations-\ud \ud The cross-sectional design, the use of self-reported wish to die as a measure of suicide ideation, and that suicidal ideation and suicide attempts were only assessed among those who had depressive symptoms, could be considered limitations of our study.\ud \ud Conclusions-\ud \ud Food insecurity was positively associated with suicidal ideation and suicide attempts. Targeting food insecurity among older adults in LMICs may lead to reduction in suicidal ideation and suicide attempts, although future longitudinal studies are warranted to confirm this.
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- 2022
8. How much does prosody help word segmentation? A simulation study on infant-directed speech
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Emmanuel Dupoux, Reiko Mazuka, Alejandrina Cristia, Bogdan Ludusan, RIKEN Center for Brain Science [Wako] (RIKEN CBS), RIKEN - Institute of Physical and Chemical Research [Japon] (RIKEN), Department of Psychology and Neuroscience, Duke University [Durham], Laboratoire de sciences cognitives et psycholinguistique (LSCP), Département d'Etudes Cognitives - ENS Paris (DEC), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École des hautes études en sciences sociales (EHESS)-Centre National de la Recherche Scientifique (CNRS), Apprentissage machine et développement cognitif (CoML), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École des hautes études en sciences sociales (EHESS)-Centre National de la Recherche Scientifique (CNRS)-Département d'Etudes Cognitives - ENS Paris (DEC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École des hautes études en sciences sociales (EHESS)-Centre National de la Recherche Scientifique (CNRS)-Inria de Paris, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), École des hautes études en sciences sociales (EHESS), The research reported in this paper was partly funded by JSPS Grant-in-Aid for Scientific Research (16H06319, 20H05617) and MEXT Grant-in-aid on Innovative Areas #4903 (Co-creative Language Evolution), 17H06382 to RM. It was also supported by the European Research Council (ERC-2011-AdG-295810 BOOTPHON), the Agence Nationale pour la Recherche (ANR-17-CE28-0007 LangAge, ANR-16-DATA-0004 ACLEW, ANR-14-CE30-0003 MechELex, ANR-17-EURE-0017 Frontcog, ANR-10-IDEX-0001-02 PSL*, ANR-19-P3IA-0001 PRAIRIE 3IA Institute). ED is further grateful to the CIFAR (Learning in Machines and Brain), BL to the Canon Foundation in Europe, and AC to the JS McDonnell Foundation., ANR-17-CE28-0007,LangAge,Différences dans l'apprenabilité du langage selon l'âge(2017), ANR-16-DATA-0004,ACLEW,Analyzing Child Language Experiences Around the World(2016), ANR-14-CE30-0003,MechELex,Méchanismes d'acquisition lexicale précoce(2014), ANR-17-EURE-0017,FrontCog,Frontières en cognition(2017), ANR-19-P3IA-0001,PRAIRIE,PaRis Artificial Intelligence Research InstitutE(2019), European Project: 295810,EC:FP7:ERC,ERC-2011-ADG_20110406,BOOTPHON(2012), École normale supérieure - Paris (ENS Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris)
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Linguistics and Language ,Cognitive Neuroscience ,Speech recognition ,Experimental and Cognitive Psychology ,Prosody ,Infant-directed speech ,050105 experimental psychology ,Language and Linguistics ,Speech Acoustics ,Task (project management) ,Infant language acquisition ,Developmental and Educational Psychology ,Humans ,Learning ,Speech ,0501 psychology and cognitive sciences ,Segmentation ,Computer Simulation ,ComputingMilieux_MISCELLANEOUS ,Computational model ,05 social sciences ,Text segmentation ,Infant ,acquisition ,[SCCO.LING]Cognitive science/Linguistics ,Word segmentation ,[SCCO.PSYC]Cognitive science/Psychology ,Speech Perception ,Infant language ,Cues ,Heuristics ,Psychology ,Word (computer architecture) ,050104 developmental & child psychology - Abstract
International audience; Infants come to learn several hundreds of word forms by two years of age, and it is possible this involves carving these forms out from continuous speech. It has been proposed that the task is facilitated by the presence of prosodic boundaries. We revisit this claim by running computational models of word segmentation, with and without prosodic information, on a corpus of infant-directed speech. We use five cognitively-based algorithms, which vary in whether they employ a sub-lexical or a lexical segmentation strategy and whether they are simple heuristics or embody an ideal learner. Results show that providing expert-annotated prosodic breaks does not uniformly help all segmentation models. The sub-lexical algorithms, which perform more poorly, benefit most, while the lexical ones show a very small gain. Moreover, when prosodic information is derived automatically from the acoustic cues infants are known to be sensitive to, errors in the detection of the boundaries lead to smaller positive effects, and even negative ones for some algorithms. This shows that even though infants could potentially use prosodic breaks, it does not necessarily follow that they should incorporate prosody into their segmentation strategies, when confronted with realistic signals.
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- 2022
9. An open-source camera system for experimental measurements
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Miikki, Kim, Karakoç, Alp, Rafiee, Mahdi, Lee, Duck Weon, Vapaavuori, Jaana, Tersteegen, Jennifer, Lemetti, Laura, Paltakari, Jouni, School common, CHEM, Department of Communications and Networking, Department of Bioproducts and Biosystems, Department of Chemistry and Materials Science, Biomolecular Materials, Paper Converting and Packaging, Aalto-yliopisto, and Aalto University
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QA76.75-76.765 ,Non-contact optical measurements ,Raspberry Pi ,Computer software ,Digital image processing ,Open-source initiative - Abstract
Funding Information: KM and AK generated the concept. KM, as the main programmer, and AK wrote the scripts to realize the work. KM, AK and MR conducted DIC owing to Kim Widell at the Department of Mechanical Engineering, Aalto University. DL and JV conducted photoisomerization experiments and the RGB analysis, JT and LL carried out lap shear tests with the high-speed camera option. KM conducted the contact (wetting) angle measurements with Timo Kotilahti and MR. All the authors contributed to the manuscript writing while AK edited and finalized the manuscript. DL and JV gratefully acknowledge the funding from Academy of Finland SUPER-WEAR project (decision number 322214 ). AK gratefully acknowledges the Research Fellowship at the School of Electrical Engineering and funding from the Academy of Finland BESIMAL project (decision number 334197 ). Funding Information: KM and AK generated the concept. KM, as the main programmer, and AK wrote the scripts to realize the work. KM, AK and MR conducted DIC owing to Kim Widell at the Department of Mechanical Engineering, Aalto University. DL and JV conducted photoisomerization experiments and the RGB analysis, JT and LL carried out lap shear tests with the high-speed camera option. KM conducted the contact (wetting) angle measurements with Timo Kotilahti and MR. All the authors contributed to the manuscript writing while AK edited and finalized the manuscript. DL and JV gratefully acknowledge the funding from Academy of Finland SUPER-WEAR project (decision number 322214). AK gratefully acknowledges the Research Fellowship at the School of Electrical Engineering and funding from the Academy of Finland BESIMAL project (decision number 334197). Publisher Copyright: © 2021 The Author(s) Copyright: Copyright 2021 Elsevier B.V., All rights reserved. We present an affordable, yet accurate and modular camera system solution developed on Raspberry Pi 4/4 GB platform with Raspberry v2.x and HQ camera modules with 8 and 12.3 megapixels still resolutions, respectively. The system uses freely available Python scripts and libraries for digital image processing and non-contact optical measurements under MIT licenses as a contribution to the open-source initiative. Several investigations were conducted with the present system, which were two-dimensional (2D) digital image correlation (DIC) for the displacement and strain analysis, the kinetic analysis of the photoisomerization of the spiropyran (a model system for a time-dependent chemical reaction yielding molecules with differing color with respect to starting material) with time-lapse photography, lap shear tests with the assistance of high-speed image capturing and contact (wetting) angle measurements with still images and time-lapse photography. These studies show that the camera system, setups and scripts can be confidently integrated into the chemical, physical and mechanical tests.
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- 2021
10. The impact of diabetes on heart failure development: the cardio-renal-metabolic connection
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Paul Valensi, Jean-Michel Halimi, Erwan Donal, Sara Pinto, Gaëtan Prévost, Jonchère, Laurent, Service d'endocrinologie diabétologie, nutrition (Hôpital Jean Verdier), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Hôpital Jean Verdier [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Université Sorbonne Paris Nord, Centre de Recherche en Nutrition Humaine d'Ile-de-France (CRNH-IDF), Institut de Veille Sanitaire (INVS)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Conservatoire National des Arts et Métiers [CNAM] (CNAM), HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM)-HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM)-Institut National Agronomique Paris-Grignon (INA P-G)-CETAF-Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Sorbonne Paris Nord, CHU Rouen, Normandie Université (NU), Service de néphrologie et immunologie clinique [CHRU Tours], Centre Hospitalier Régional Universitaire de Tours (CHRU Tours)-Hôpital Bretonneau-Université de Tours (UT), Laboratoire Traitement du Signal et de l'Image (LTSI), Université de Rennes (UR)-Institut National de la Santé et de la Recherche Médicale (INSERM), CHU Pontchaillou [Rennes], For this review paper the authors did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors., Institut de Veille Sanitaire (INVS)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Institut National Agronomique Paris-Grignon (INA P-G)-CETAF-Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Sorbonne Paris Nord, Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National de la Santé et de la Recherche Médicale (INSERM), Service de néphrologie et immunologie clinique [CHRU Tours] (EA4245 UT), and Centre Hospitalier Régional Universitaire de Tours (CHRU Tours)-Université de Tours-Hôpital Bretonneau
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medicine.medical_specialty ,GLP1-receptor agonists ,Endocrinology, Diabetes and Metabolism ,Population ,heart failure ,030209 endocrinology & metabolism ,Type 2 diabetes ,urologic and male genital diseases ,[SDV.MHEP.UN]Life Sciences [q-bio]/Human health and pathology/Urology and Nephrology ,Coronary artery disease ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,[SDV.MHEP.CSC]Life Sciences [q-bio]/Human health and pathology/Cardiology and cardiovascular system ,Diabetes mellitus ,Internal Medicine ,medicine ,Humans ,030212 general & internal medicine ,Renal Insufficiency, Chronic ,education ,Intensive care medicine ,Contraindication ,[SDV.IB] Life Sciences [q-bio]/Bioengineering ,education.field_of_study ,business.industry ,Diabetes ,General Medicine ,medicine.disease ,[SDV.MHEP.UN] Life Sciences [q-bio]/Human health and pathology/Urology and Nephrology ,3. Good health ,[SDV.MHEP.CSC] Life Sciences [q-bio]/Human health and pathology/Cardiology and cardiovascular system ,Natural history ,Diabetes Mellitus, Type 2 ,Heart failure ,[SDV.IB]Life Sciences [q-bio]/Bioengineering ,business ,SGLT2 inhibitors ,chronic kidney disease ,coronary artery disease ,Kidney disease - Abstract
Heart failure (HF) and chronic kidney disease (CKD) are often associated in type 2 diabetes (T2D), aggravate each other and exert synergistic effects to increase the risk of cardiac and renal events. The risks of renal worsening in HF patients and HF in CKD patients need to be evaluated to tailor preventive therapy. The recent CV and renal trials enriched our knowledge about the natural history of HF and CKD in T2D and provided evidence for the benefit of sodium-glucose cotransporter 2 inhibitors (SGLT2is) in HF and renal decline prevention. SGLT-2is are the best choice in patients with HFrEF to improve CV prognosis and HF-related outcomes and also to prevent kidney-related outcomes, and in CKD patients to slow down renal failure and also reduce hospitalization for HF and CV death. In both situations the number of patients to treat in order to prevent such events in one patient is lower than in the general T2D population at high CV risk. GLP1-receptor agonists could be an alternative in a patient who is intolerant or has a contraindication to SGLT-2is. A tight collaboration between diabetologists, nephrologists and cardiologists should be encouraged for a holistic and effective strategy to reduce the burden of cardio-renal-metabolic interaction.
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- 2021
11. New data for the Early Upper Paleolithic of Kostenki (Russia)
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Andrei Sinitsyn, Thibaut Devièse, Natasha Reynolds, Mikhail V. Sablin, Thomas Higham, Alexander Bessudnov, Rob Dinnis, Abi Pate, British Museum, Institute for the History of Material Culture [St Petersburg], the Russian Academy of Sciences [Moscow, Russia] (RAS), De la Préhistoire à l'Actuel : Culture, Environnement et Anthropologie (PACEA), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS), School of Archaeology [Oxford], University of Oxford, Zoological Institute, Russian Academy of Sciences [Moscow] (RAS), This research was supported by the Leverhulme Trust (RPG-2012-800). A.B.'s work was supported by grants RFBR18-39-20009 and RSF18-78-00136, and by state assignment 0184-2018-0012. NR was supported during the writing of this paper by a Postdoctoral Study Grant from the Fondation Fyssen and the European Union's Horizon 2020 research and innovation programme under Marie Skłodowska-Curie grant agreement No 747400. A.S. acknowledges grant RFBR17-06-00319a and state assignment 0184-2018-0012, and we also acknowledge the participation of ZIN RAS (state assignment АААА-А17-117022810195-3). The research that enabled the production of HYP radiocarbon dates came from the European Research Council under the European Union's Seventh Framework Programme (FP7/2007-2013), ERC grant 324139 'PalaeoChron', which also supported N.R., T.D. and T.H., European Project: 324139,EC:FP7:ERC,ERC-2012-ADG_20120411,PALAEOCHRON(2013), European Project: 747400,PeOPLE, and University of Oxford [Oxford]
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Radiocarbon dating ,Bladelet technology ,010506 paleontology ,Neanderthal ,[SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory ,Archaeological record ,Eastern Europe ,01 natural sciences ,law.invention ,law ,biology.animal ,Assemblage (archaeology) ,0601 history and archaeology ,Ecology, Evolution, Behavior and Systematics ,0105 earth and related environmental sciences ,060101 anthropology ,biology ,Anatomically modern humans ,06 humanities and the arts ,Archaeology ,Geography ,Early Upper Palaeolithic ,Anthropology ,Upper Paleolithic ,Period (geology) ,Kostenki ,Aurignacian ,Chronology - Abstract
Several questions remain regarding the timing and nature of the Neanderthal-anatomically modern human (AMH) transition in Europe. The situation in Eastern Europe is generally less clear due to the relatively few sites and a dearth of reliable radiocarbon dates. Claims have been made for both notably early AMH and notably late Neanderthal presence, as well as for early AMH (Aurignacian) dispersal into the region from Central/Western Europe. The Kostenki-Borshchevo complex (European Russia) of Early Upper Paleolithic (EUP) sites offers high-quality data to address these questions. Here we revise the chronology and cultural status of the key sites of Kostenki 17 and Kostenki 14. The Kostenki 17/II lithic assemblage shares important features with Proto-Aurignacian material, strengthening an association with AMHs. New radiocarbon dates for Kostenki 17/II of ∼41–40 ka cal BP agree with new dates for the recently excavated Kostenki 14/IVw, which shows some similarities to Kostenki 17/II. Dates of ≥41 ka cal BP from other Kostenki sites cannot be linked to diagnostic archaeological material, and therefore cannot be argued to date AMH occupation. Kostenki 14's Layer in Volcanic Ash assemblage, on the other hand, compares to Early Aurignacian material. New radiocarbon dates targeting diagnostic lithics date to 39–37 ka cal BP. Overall, Kostenki's early EUP is in good agreement with the archaeological record further west. Our results are therefore consistent with models predicting interregional penecontemporaneity of diagnostic EUP assemblages. Most importantly, our work highlights ongoing challenges for reliably radiocarbon dating the period. Dates for Kostenki 14 agreed with the samples' chronostratigraphic positions, but standard pre-treatment methods consistently produced incorrect ages for Kostenki 17/II. Extraction of hydroxyproline from bone collagen using preparative high-performance liquid chromatography, however, yielded results consistent with the samples' chronostratigraphic position and with the layer's archaeological contents. This suggests that for some sites compound-specific techniques are required to build reliable radiocarbon chronologies.
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- 2019
12. Cross-cultural examination of college marijuana culture in five countries: Measurement invariance of the Perceived Importance of Marijuana to the College Experience Scale
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Pearson, Matthew R., Bravo, Adrián J., Sotelo, Melissa, Henson, James M., Ibáñez, Manuel I, Mezquita, Laura, Ortet, Generós, Pilatti, Angelina, Prince, Mark A., Read, Jennifer P., Roozen, Hendrik G., Ruiz, Paul, Cross‐Cultural Addictions Study Team, Henson, James M., and MRP is supported by a career development grant (K01-AA023233) from the National Institute on Alcohol Abuse and Alcoholism (NIAAA). AJB is supported by a training grant (T32-AA018108) from the NIAAA. Data collection was supported, in part, by grant T32-AA018108. NIAAA had no role in the study design, collection, analysis or interpretation of the data, writing the manuscript, or the decision to submit the paper for publication. Data collection in Spain was also supported by grants UJI-A2017-18 and UJI-B2017-74 from the Universitat Jaume I and grant PSI2015-67766-R from the Spanish Ministry of Economy and Competitiveness (MINECO). Data collection in Argentina was also supported by grants from the National Secretary of Science and Technology (FONCYT, grant number #PICT 2015-849) and by grants from the Secretary of Science and Technology- National University of Córdoba (SECyT-UNC).
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Cross-Cultural Comparison ,Male ,Universities ,education ,Psychological intervention ,Argentina ,Medicine (miscellaneous) ,Bivariate analysis ,Toxicology ,Social norms approach ,Sex Factors ,cross-cultural ,Surveys and Questionnaires ,mental disorders ,Social Norms ,Cross-cultural ,Humans ,Measurement invariance ,Students ,Netherlands ,college students ,Reproducibility of Results ,Confirmatory factor analysis ,Marijuana user ,United States ,measurement invariance ,Psychiatry and Mental health ,Clinical Psychology ,Level of measurement ,Attitude ,Spain ,college norms ,Uruguay ,Female ,Marijuana Use ,Psychology ,Factor Analysis, Statistical ,marijuana ,Clinical psychology - Abstract
This project was completed by the Cross-cultural Addictions Study Team (CAST), which includes the following investigators (in alphabetical order): Adrian J. Bravo, University of New Mexico, USA (Coordinating PI); James M. Henson, Old Dominion University, USA; Manuel I. Ibáñez, Universitat Jaume I de Castelló, Spain; Laura Mezquita, Universitat Jaume I de Castelló, Spain; Generós Ortet, Universitat Jaume I de Castelló, Spain; Matthew R. Pearson, University of New Mexico, USA; Angelina Pilatti, National University of Cordoba, Argentina; Mark A. Prince, Colorado State University, USA; Jennifer P. Read, University at Buffalo, USA; Hendrik G. Roozen, University of New Mexico, USA; Paul Ruiz, Universidad de la República, Uruguay. Marijuana internalized norms, measured by the Perceived Importance of Marijuana to the College Experience Scale (PIMCES; 8 items), has been found to be distinct from marijuana descriptive/injunctive norms and to be a unique robust predictor of marijuana-related outcomes among college students, yet the role of these beliefs has not been studied outside the U.S. Using confirmatory factor analysis, the present work examined the level of measurement invariance (i.e., configural, metric, and scalar) of the PIMCES across five different countries with distinct marijuana-related regulations (i.e., U.S., Argentina, Spain, Uruguay, and the Netherlands), sex, and marijuana user status among college students (n = 3424) recruited between September 2017 and January 2018. To make valid comparisons across groups, metric invariance is needed to compare correlations and scalar invariance is needed to compare latent means. We found strong measurement invariance (i.e., scalar invariance) for the PIMCES across countries, across males and females, and across marijuana users and non-users. College students in the U.S. reported the highest levels of marijuana internalized norms compared to college students from all other countries. As expected, males and marijuana users showed significantly higher scores on the PIMCES than females and non-users, respectively. Bivariate correlations between PIMCES scores and other marijuana-related variables were remarkably similar across males and females, though differences across countries warrant further exploration. Taken together, the degree to which college students view marijuana use to be an integral part of the college experience may be an important target for college student marijuana interventions across various countries/cultures.
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- 2019
13. Impulsivity-related traits, college alcohol beliefs, and alcohol outcomes: Examination of a prospective multiple mediation model among college students in Spain, Argentina, and USA
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Generós Ortet, Angelina Pilatti, Laura Mezquita, Manuel I. Ibáñez, Matthew R. Pearson, Adrian J. Bravo, Jennifer P. Read, and Dr. Pearson is supported by a career development grant (K01-AA023233) from the National Institute of Alcohol Abuse and Alcoholism (NIAAA) and Dr. Bravo is supported by a training grant (T32-AA018108) from the NIAAA. Data collection across all sites was supported, in part, by grant T32-AA018108. NIAAA had no role in the study design, collection, analysis or interpretation of the data, writing the manuscript, or the decision to submit the paper for publication. Data collection in Spain was also supported, in part, by grants PSI2015-67766-R from the Spanish Ministry of Economy and Competitiveness (MINECO/FEDER) and GV/2016/158 from the Autonomous Government of Valencia.
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Male ,050103 clinical psychology ,Mediation (statistics) ,Universities ,Argentina ,030508 substance abuse ,Medicine (miscellaneous) ,impulsivity ,Toxicology ,Impulsivity ,03 medical and health sciences ,Young Adult ,cross-cultural ,Cultural diversity ,medicine ,Cross-cultural ,Sensation seeking ,Humans ,0501 psychology and cognitive sciences ,Prospective Studies ,Students ,alcohol ,05 social sciences ,college students ,Cognition ,Drinking culture ,Alcohol Drinking in College ,United States ,Psychiatry and Mental health ,Clinical Psychology ,Cross-Sectional Studies ,Attitude ,Spain ,Impulsive Behavior ,Trait ,Female ,medicine.symptom ,0305 other medical science ,Psychology ,Alcohol-Related Disorders ,college alcohol beliefs ,Clinical psychology ,Personality - Abstract
Objectives: The present study examined (both cross-sectionally and prospectively) the mediational role of college alcohol beliefs in the relationship between impulsivity-related traits and alcohol outcomes (i.e., alcohol use and negative consequences) among college student drinkers from the United States (U.S.), Spain, and Argentina. Method: A sample of 1429 (U.S. = 733, Spain = 292, Argentina = 404) drinkers (at least one drinking episode within the previous month) completed the baseline survey, and 242 drinkers completed the follow-up. To test study aims, a cross-sectional model was first employed to examine whether the proposed double-mediated paths (i.e., each dimension of impulsivity → college alcohol beliefs → alcohol use → negative alcohol-related consequences) extends across samples with different cultural backgrounds (i.e., structural invariance testing). A longitudinal model was then conducted to assess if college alcohol beliefs prospectively mediate the associations between trait impulsivity and alcohol outcomes. Results: College alcohol beliefs were concurrently and prospectively associated with both greater alcohol use and increased number of negative alcohol-related consequences. These internalized beliefs about college student drinking culture significantly mediated the effects of several distinct impulsivity-related traits on alcohol-related outcomes including urgency (positive and negative), sensation seeking, and perseverance. These findings were invariant across gender and across three countries (Argentina, Spain, and the U.S.). Conclusions: Our findings highlight the modulatory role of cognitive factors on problematic alcohol use among college students with different cultural backgrounds. Our results suggest that, despite the cultural differences exhibited by these three countries, the unique and mediational effects of college alcohol beliefs appear relatively universal.
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- 2018
14. Convergence regions for the Chebyshev–Halley family
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B. Campos, Jordi Canela, P. Vindel, and The authors would like to thank the anonymous referees for their suggestions and comments, which improved this paper. The first and third authors were supported by the Spanish project MTM2014-52016-C02-2-P, the Generalitat Valenciana Project PROMETEO/2016/089 and UJI project P1.1B20115-16. The second author was supported by RedIUM and MINECO (Spain) through the research network MTM2014-55580-REDT and by the mathematics institute IMAC (Castellon, Spain).
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roots ,Numerical Analysis ,Pure mathematics ,Chebyshev–Halley family ,Iterative method ,polynomials ,Applied Mathematics ,Chebyshev systems ,010102 general mathematics ,010103 numerical & computational mathematics ,dynamics ,Parameter space ,Fixed point ,01 natural sciences ,Attraction ,Chebyshev filter ,Critical point (mathematics) ,Combinatorics ,Quadratic equation ,Modeling and Simulation ,Polinomis ,0101 mathematics ,Sistemes de Chebyshev ,Mathematics - Abstract
In this paper we study the dynamical behavior of the Chebyshev–Halley methods on the family of degree n polynomials z n + c . We prove that, despite increasing the degree, it is still possible to draw the parameter space by using the orbit of a single critical point. For the methods having z = ∞ as an attracting fixed point, we show how the basins of attraction of the roots become smaller as the value of n grows. We also demonstrate that, although the convergence order of the Chebyshev–Halley family is 3, there is a member of order 4 for each value of n. In the case of quadratic polynomials, we bound the set of parameters which correspond to iterative methods with stable behaviour other than the basins of attraction of the roots.
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- 2018
15. Lignin-containing cellulose nanocrystals enhanced electrospun polylactic acid-based nanofibrous mats: Strengthen and toughen.
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Ouyang C, Zhang H, Zhu Y, Zhao J, Ren H, and Zhai H
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Biodegradable polylactic acid (PLA) nanofibrous mats prepared by electrospinning serve as suitable packaging materials. However, their practical applications are limited by their weak mechanical properties, poor thermal stability, and high cost. In this study, green and low-cost lignin-containing cellulose nanocrystals (LCNCs) with different lignin contents were developed and employed as reinforced materials to synergistically enhance the thermal, mechanical, and hydrophobic properties of PLA electrospun nanofibrous mats. The presence of moderate lignin improved the interfacial compatibility between the LCNCs and PLA, resulting in excellent mechanical properties of the nanofibrous mats. Compared to pure PLA mats, the tensile strength of the composites reached up to 21.0 MPa, representing a 6.6-fold increase. Its toughness was synchronously enhanced by 16 times, reaching a maximum of 3.6 MJ/m
3 . The maximum decomposition temperature of PLA/LCNCs electrospun nanofibrous mats increased from 339 °C to 365 °C. Furthermore, the increase in lignin in the LCNCs positively contributed to improving the hydrophobicity of the PLA/LCNCs electrospun nanofibrous mats. This bio-based strategy of LCNCs employed in the enhancement of fully bio-based PLA nanofibrous mats offers a viable approach for the advancement of packaging films., Competing Interests: Declaration of competing interest We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence this work, there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
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16. A recyclable dispersant based on carbomer utilizing controllable viscosity for high-efficiency dispersion of carbon fibers.
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Yuan T, Wu J, Luo H, Jiang Y, Sun Q, Jia L, Wang K, Zhang X, Li J, Wu J, Sha L, and Guo D
- Abstract
Good dispersion of carbon fibers is important for the carbon paper production, which is usually achieved using low carbon fiber concentrations and disposable dispersants. In this study, we developed carbomer as a recyclable and high-efficiency dispersant for carbon fibers. When the carbon fiber concentration was 0.1 wt%, carbon fiber suspension showed improved dispersion performance as increasing the carbomer dosage. It exhibited low Turbiscan Stability Index (TSI) of 0.41 and small change of delta backscattering between -0.5 to 0.8 % when using 0.5 wt% carbomer. However, the good dispersibility fade away when increasing the concentration of carbon fibers. Subsequently, the pH of the carbon fiber suspension was adjusted to 7.0 to improve the dispersibility by increasing the viscosity, but causing a worse flowability. Then the pH was further adjusted to 13.0 to ensure good flowability in the wet-forming process and good dispersibility at carbon fiber concentration of 0.5 wt%. More importantly, the dispersant was successfully recycled and still exhibited excellent dispersion effects for carbon fibers after 5 cycles. Notably, the high-efficiency dispersion of carbon fibers and the recyclability of dispersant were achieved simultaneously for the first time, which is suitable for the eco-friendly and sustainable production of carbon paper., Competing Interests: Declaration of competing interest We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influences our work. There is no professional or other personal interest of any nature or kind in any product., (Copyright © 2024 Elsevier B.V. All rights reserved.)
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- 2024
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17. Lignin hydrogel sensor with anti-dehydration, anti-freezing, and reproducible adhesion prepared based on the room-temperature induction of zinc chloride-lignin redox system.
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Shi Y, Lv H, Zhao Q, Wen X, Wu J, Xu Z, Zong S, and Duan J
- Abstract
In recent years, flexible sensors constructed mainly from hydrogels have received increasing attention. However, conventional hydrogels need to be prepared by high-temperature or radiation-induced polymerization reactions, which limits their practical applications due to their suboptimal electrical conductivity and weak mechanical properties. In this paper, using sodium lignosulfonate as the raw material, a dynamic catechol-quinone redox system formed by lignin‑zinc ions was constructed to initiate rapid free radical polymerization of acrylamide (AM) monomer at room temperature. In addition, Deep eutectic solvent (DES) can form a strong hydrogen bonding network within the molecules and between the molecules of the hydrogel, resulting in a hydrogel with good tensile properties (hydrogel elongation at break of 727.19 %, breaking strength of 84.09 kPa), and provides the hydrogel with high electrical conductivity, anti-dehydration, anti-freezing, and anti-bacterial properties. Meanwhile, the addition of lignin also improved the adhesion and UV resistance of the hydrogel. This hydrogel assembled into a flexible sensor can sense various small and large amplitude movements such as nodding, smiling, frowning, etc., and has a wide range of applications in flexible sensors., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)
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- 2024
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18. Multi-dimensional microfluidic paper-based analytical devices (μPADs) for noninvasive testing: A review of structural design and applications.
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Chen T, Sun C, Abbas SC, Alam N, Qiang S, Tian X, Fu C, Zhang H, Xia Y, Liu L, Ni Y, and Jiang X
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- Humans, Equipment Design, Saliva chemistry, Point-of-Care Testing, Paper, Microfluidic Analytical Techniques instrumentation, Lab-On-A-Chip Devices
- Abstract
The rapid emergence of microfluidic paper-based devices as point-of-care testing (POCT) tools for early disease diagnosis and health monitoring, particularly in resource-limited areas, holds immense potential for enhancing healthcare accessibility. Leveraging the numerous advantages of paper, such as capillary-driven flow, porous structure, hydrophilic functional groups, biodegradability, cost-effectiveness, and flexibility, it has become a pivotal choice for microfluidic substrates. The repertoire of microfluidic paper-based devices includes one-dimensional lateral flow assays (1D LFAs), two-dimensional microfluidic paper-based analytical devices (2D μPADs), and three-dimensional (3D) μPADs. In this comprehensive review, we provide and examine crucial information related to paper substrates, design strategies, and detection methods in multi-dimensional microfluidic paper-based devices. We also investigate potential applications of microfluidic paper-based devices for detecting viruses, metabolites and hormones in non-invasive samples such as human saliva, sweat and urine. Additionally, we delve into capillary-driven flow alternative theoretical models of fluids within the paper to provide guidance. Finally, we critically examine the potential for future developments and address challenges for multi-dimensional microfluidic paper-based devices in advancing noninvasive early diagnosis and health monitoring. This article showcases their transformative impact on healthcare, paving the way for enhanced medical services worldwide., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
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- 2024
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19. Enhancing enzymatic conversion of castor stalk through dual-functional ethanolamine pretreatment.
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He Y, Xing Y, Shao L, Ling Z, Yang G, Xu F, and Wang C
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Castor stalk from hemp plants is an attractive lignocellulosic feedstock for biomass refining valorization due to its similar chemical composition to hardwoods. In this study, the castor stalk fibers were pretreated with efficient dual-functional ethanolamine to achieve delignification and swelling of the cellulosic fibers, followed by cellulase enzymatic digestion for biomass conversion. Experimental results showed that ethanolamine pretreatment at 160 °C for 1 h effectively removed 69.20 % of lignin and 43.18 % of hemicellulose. In addition to efficient delignification and removal of hemicellulose, the study also revealed that supramolecular structure of cellulose was another major factor affecting enzymatic hydrolysis performance. The lowered crystallinity (60-70 %) and swelled crystal sizes (2.95-3.04 nm) promoted enzymatic hydrolysis efficiency during the heterogeneous reaction process. Under optimal conditions (160 °C, 1 h; enzyme loading: 15 FPU/g substrate), promoted yields of 100 % glucose and over 90 % xylose were achieved, which were significantly higher than those obtained from untreated castor stalk. These findings highlighted the effectiveness of the dual-functional ethanolamine pretreatment strategy for efficient bioconversion of lignocellulosic feedstocks. Overall, this study provides valuable insights into the development of new strategies for the efficient utilization of biomass resources, which is essential for the sustainable development of our society., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)
- Published
- 2024
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20. Carboxymethyl cellulose-based photothermal film: A sustainable packaging with high barrier and tensile strength for food long-term antibacterial protection.
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Zhang X, Yang G, Jiang Q, Fan J, Wang S, and Chen J
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- Polyvinyl Alcohol chemistry, Nanoparticles chemistry, Food Packaging methods, Carboxymethylcellulose Sodium chemistry, Anti-Bacterial Agents pharmacology, Anti-Bacterial Agents chemistry, Tensile Strength, Copper chemistry, Copper pharmacology, Escherichia coli drug effects, Staphylococcus aureus drug effects
- Abstract
Traditional packaging materials feed the growing global food protection. However, these packaging materials are not conducive to environment and have not the ability to kill bacteria. Herein, a green and simple strategy is reported for food packaging protection and long-term antibacterial using carboxymethylcellulose-based photothermal film (CMC@CuS NPs/PVA) that consists of carboxymethyl cellulose (CMC) immobilized copper sulfide nanoparticles (CuS NPs) and polyvinyl alcohol (PVA). With satisfied oxygen transmittance (0.03 cc/m
2 /day) and water vapor transmittance (163.3 g/m2 /day), the tensile strength, tear strength and burst strength reached to 3401.2 N/m, 845.7 mN and 363.6 kPa, respectively, which could lift 4.5 L of water. The composite film had excellent photothermal conversion efficiency and photothermal stability. Under the irradiation of near infrared (NIR), it can rapidly heated up to 197 °C within 25 s. The antibacterial analysis showed that the inhibition rate of composite film against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) could all reach >99 %. Furthermore, the synthesized CuS NPs was well immobilized and the residual rate of copper kept 98.7 % after 10 days. Noticeably, the composite film can preserve freshness of strawberries for up to 6 days. Therefore, the composite film has potential application for food antibacterial protection., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
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21. Immobilization of multilayer sodium alginate/polysaccharide antibacterial material composite beads as glufosinate controlled release matrices.
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Li C, Zhang Q, Sheng X, Li N, Ping Q, and Zhang J
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- Kinetics, Chitosan chemistry, Microspheres, Polysaccharides chemistry, Hydrogen-Ion Concentration, Drug Liberation, Temperature, Aminobutyrates, Alginates chemistry, Anti-Bacterial Agents chemistry, Anti-Bacterial Agents pharmacology, Delayed-Action Preparations
- Abstract
To find a new way to slow down the release of glufosinate (GA) pesticide and to solve the susceptibility to decomposition by soil microorganisms, a series of novel antibacterial polysaccharide-based sustained release beads (PSRB) were prepared. The PSRB was prepared by immobilization of GA loaded polysaccharide-based chitosan quaternary ammonium salt (PS-HACC) microcapsules in the core and layers of the multilayer sodium alginate beads. The PSRB was characterized by FI-IR spectroscopy, XRD, SEM, and BET to reveal their composition and surface morphology. The optimal conditions of the slow release beads were as follows, the concentration of Ca
2+ , pH, temperature and the coating layer number was 0.1 mol/L, 7, 25 °Cand 3, respectively. The kinetic study showed that the slow release of PSRB was in accordance with the Higuchi kinetic model, and the FI-IR and XRD analyses revealed that the PS-HACC and GA were successfully cross-linked to the PSRB. BET showed that PSRB were greater than PSRB3 at surface area, pore volume and pore size. Inhibition circles experiments demonstrated that WPSRB3 has good antibacterial activity. The weed control in soybean with PSRB3 application is perfect and the weed control cycle is long. Therefore, this technology can provide a potential way to control GA release, improve utilization efficiency, reduce pesticide use and environmental pollution, and at the same time, provide a potential way to achieve ecological agriculture., Competing Interests: Declaration of competing interest The authors declare no competing financial interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
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22. "Top-down" overexpression optimization of butelase-1 in Escherichia coli and its application in anti-tumor peptides.
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Zhao J, Song W, Huang Z, Yuan X, Huang Y, Hou Y, Liu K, Jin P, and Hu SQ
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- Humans, Peptides chemistry, Peptides metabolism, Peptides genetics, Recombinant Proteins genetics, Recombinant Proteins metabolism, Recombinant Proteins chemistry, Gene Expression, Animals, Mice, Escherichia coli genetics, Escherichia coli metabolism, Antineoplastic Agents pharmacology, Antineoplastic Agents chemistry
- Abstract
Butelase-1, the fastest known Asn/Asp-specific peptide ligase capable of catalyzing peptide ligation and cyclization, holds promising application prospects in the fields of food and biology. However, limited research exists on its recombinant expression and potential applications in peptide drugs. In this study, the activity of recombinantly-produced butelase-1 was enhanced by co-expressing it with a molecular chaperone in the SHuffle T7 strain. By introducing single or multiple synonymous rare codons at the beginning of the coding regions of beta-strand or alpha-helix, in combination with ribosomal binding site engineering, the activity of butelase-1 could be further improved. Consequently, the butelase-1 with a specific activity of 386.93 U/mg and a catalytic efficiency of 11,048 M
-1 s-1 was successfully prepared in E. coli, resulting in a total activity of 8183.54 U/L and a yield of about 100 mg/L. This optimized butelase-1 was then used to efficiently cyclize the redesigned anti-cancer peptide lunasin, leading to enhanced bioavailability and anti-cancer effects. Overall, this study not only provided valuable biotechnology strategies for improving the recombinant expression of butelase-1 but also demonstrated a successful application for enhancing the biological efficacy of anti-cancer peptides., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
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23. A tough, stretchable, adhesive and electroconductive polyacrylamide hydrogel sensor incorporated with sulfonated nanocellulose and carbon nanotubes.
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Deng W, Zhang Y, Wu M, Liu C, Rahmaninia M, Tang Y, and Li B
- Abstract
Recently, hydrogel sensors have been widely applied in wearable and portable electronics, but the low mechanical property, intolerance of fatigue, and low sensitivity and adhesion limit their further applications. In this study, sulfonated nanocellulose (SCNF) with dual functionality was blended into polyacrylamide (PAM) hydrogel matrix to reinforce the mechanical strength and facilitate the homogeneous dispersion of carbon nanotubes (CNTs). The SCNF-CNT/PAM hydrogel was designed through free radical polymerization to achieve commendable mechanical, electrical, and multifunctional properties. The environmental-friendly SCNF serves as bio-templates to facilitate the assembling of CNT into integrated SCNF-CNT structures with good dispersity, thus enabling the establishment of an integrated conducting and reinforcing network. The fabricated SCNF-CNT/PAM hydrogel exhibited outstanding compressive strength (∼0.45 MPa at 50 % strain), tensile strength (∼169.12 kPa), and antifatigue capacity under cyclic stretching and pressing. Furthermore, the multifunctional sensors assembled using this hydrogel demonstrated high strain sensitivity (gauge factor ~ 3.7 at 100-400 % strain) and effectively detected human motions. This design principle provides promising prospects for constructing next-generation multifunctional flexible sensors, and the integration of these distinctive properties enables the prepared composite hydrogels to find potential applications in various areas, such as implantable soft electronic devices, electronic skin, and human movement monitoring., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
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24. Opportunity for valorization of pulping by-product in production high performance sustaining release lignin-based gel.
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Basta AH and Lotfy VF
- Abstract
This study focuses on optimizing the pulping by-product to produce effective hydrogels for controlling the release of salicylic acid (SA). In this regard, two routes are achieved: the first involves preparing black liquor (BL) composite hydrogels with various polymer macromolecules [polyacrylamide (PAM), polyvinyl alcohol (PVA), and chitosan (Cs), and the second involves carboxymethylation of BL and grafting with acrylamide. Hydrogels are evaluated using spectral analysis (ATR-FTIR), thermal analysis (TGA and DTG), and swelling measures. Encapsulation, release profile, SA release kinetics, as well as ATR-FTIR and SEM measurements, were used to evaluate the behavior of loaded hydrogels. According to the results, grafted carboxymethylated BL-gel had the maximum SA release (98.7 %), followed by PAM-BL (51.7 %) and PAM/PVA-BL (43.1 %). Over a 48-hour period, the hydrogels demonstrated a prolonged SA release pattern. The Ritger-Peppas and Higuchi models fitted to all examined hydrogels showed that SA release followed both Fickian and non-Fickian diffusion pathways., Competing Interests: Declaration of competing interest Authors declare that there is no conflict among the contributing author related to the financial or non-financial interests that are directly or indirectly related to the work submitted for publication., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
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25. Extraction and characterization of novel Prosopis Juliflora bark and Boehmeria nivea fibre for use as reinforcement in the hybrid composites with the effect of curing temperature, fibre length and weight percentages.
- Author
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Arivendan A, Keerthiveettil Ramakrishnan S, Chen X, Zhang YF, Gao W, Syamani FA, Thangiah WJJ, and Siva I
- Abstract
The hybrid composite sample based on Prosopis Juliflora (PJ) bark and ramie fibre with different length, weight percentage, and curing temperature were created for the first time in this work. Totally, 120 hybrid composite samples were tested in this study. There were five different fibre lengths: 10 mm, 15 mm, 20 mm, 25 mm, and 30 mm, weight percentages 10 %, 20 %, 30 %, 40 %, and 50 %, and different curing temperatures 80 °C, 90 °C, 100 °C, 110 °C, and 120 °C used to produce the hybrid composite samples. Due to the cross-linking ability with the epoxy matrix, the hybrid composite specimen shows high resistance up to 98 Shore D hardness. The high polarity of the epoxy matrix and the hydrogen bond strengthening effect, increased the composite sample flexural strength by 12 %. The curing temperature of 100 °C, 20 mm fibre length, and 30 % of the hybrid composite sample achieved the highest tensile strength (28.76 MPa), flexural strength (46.54 MPa), impact strength (4.5 J), and hardness strength properties (98 shore D). Thermo gravimetric analysis (TGA) revealed the composite samples initial decomposition temperature (T
i ) at 98 °C, maximum decomposition temperature (Tmax ) at 320 °C, and the final decomposition temperature (Tf ) at 466 °C., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
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26. Heat-sealable, transparent, and degradable arabinogalactan/polyvinyl alcohol films with UV-shielding, antibacterial, and antioxidant properties.
- Author
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Zhang H, Li M, Liu Z, Li R, and Cao Y
- Subjects
- Benzaldehydes chemistry, Hot Temperature, Tensile Strength, Polyvinyl Alcohol chemistry, Antioxidants chemistry, Antioxidants pharmacology, Anti-Bacterial Agents chemistry, Anti-Bacterial Agents pharmacology, Ultraviolet Rays, Galactans chemistry
- Abstract
Petroleum-based packaging materials are nondegradable and unsustainable and thus are harmful to the environment. Renewable packaging films prepared from bio-based raw materials are promising alternatives to petroleum-based packaging materials. In this study, colorless and transparent bio-based films were successfully cast using a solution containing a mixture of arabinogalactan (AG) and poly (vinyl alcohol) (PVA). Vanillin was incorporated into the mixture to endow the films with UV-shielding, antioxidant, and antibacterial properties. The morphological, physical, antioxidant, and antibacterial properties of the blend films were then characterized. At an AG:PVA weight ratio of 1:3, and the vanillin content was 0.15 %, the tensile strength of the AG/PVA/Vanillin (APV) films reached ~28 MPa, while their elongation at break reached ~475 %. The addition of vanillin significantly affected the antioxidant and antibacterial properties of the blend films, which exhibited superb UV barrier capacity. The APV films exhibited extremely low oxygen transmittance, delaying the onset of mold/rot in strawberries and reducing their weight loss. Because of the heat sealability of the blend films, they can be used for encapsulating various substances, such as concentrated laundry liquid. Moreover, the blend films were recyclable and biodegradable. Thus, these films have great potential for applications that require sustainable packaging., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024. Published by Elsevier B.V.)
- Published
- 2024
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27. Bridging papermaking and hydrogel production: Nanoparticle-loaded cellulosic hollow fibers with pitted walls as skeleton materials for multifunctional electromagnetic hydrogels.
- Author
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Yuan Z, Cheng N, Li J, Yuan H, Peng J, Qian X, Ni Y, He Z, and Shen J
- Subjects
- Electric Conductivity, Paper, Electromagnetic Phenomena, Nanoparticles chemistry, Cellulose chemistry, Hydrogels chemistry
- Abstract
Electromagnetic hydrogels have attracted significant attention due to their vast potential in soft robotics, biomedical engineering, and energy harvesting. To facilitate future commercialization via large-scale industrial processes, we present a facile concept that utilizes the specialized knowledge of papermaking to fabricate hydrogels with multifunctional electromagnetic properties. The principles of papermaking wet end chemistry, which involves the handling of interactions among cellulosic fibers, fines, polymeric additives, and other components in aqueous systems, serves as a key foundation for this concept. Notably, based on these principles, the versatile use of chemical additives in combination with cellulosic materials enables the tailored design of various products. Our methodology exploits the unique hierarchically pitted and hollow tube-like structures of papermaking grade cellulosic fibers with discernible pits, enabling the incorporation of magnetite nanoparticles through lumen loading. By combining microscale softwood-derived cellulosic fibers with additives, we achieve dynamic covalent interactions that transform the cellulosic fiber slurry into an impressive hydrogel. The cellulosic fibers act as a skeleton, providing structural support within the hydrogel framework and facilitating the dispersion of nanoparticles. In accordance with our concept, the typical hydrogel exhibits combined attributes, including electrical conductivity, self-healing properties, pH responsiveness, and dynamic rheologic behavior. Our approach not only yields hydrogels with interesting properties but also aligns with the forefront of advanced cellulosic material applications. These materials hold the promise in remote strain sensing devices, electromagnetic navigation systems, contactless toys, and flexible electronic devices. The concept and findings of the current work may shed light on materials innovation based on traditional pulp and paper processes. Furthermore, the facile processes involved in hydrogel formation can serve as valuable tools for chemistry and materials education, providing easy demonstrations of principles for university students at different levels., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2024
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28. Preparation and characterization of pectin/hydroxyethyl cellulose/clay/TiO 2 bionanocomposite films for microbial pathogen removal from contaminated water.
- Author
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Ibrahim FM, El-Liethy MA, Abouzeid R, Youssef AM, Mahdy SZA, and El Habbasha ES
- Subjects
- Wastewater chemistry, Wastewater microbiology, Escherichia coli drug effects, Staphylococcus aureus drug effects, Spectroscopy, Fourier Transform Infrared, X-Ray Diffraction, Steam, Titanium chemistry, Cellulose chemistry, Cellulose analogs & derivatives, Nanocomposites chemistry, Pectins chemistry, Clay chemistry, Water Purification methods
- Abstract
Some of conventional wastewater disinfectants can have a harmful influence on the environment as well as human health. The aim of this investigation was synthesis and characterizes ecofriendly pectin/hydroxyethyl cellulose (HEC)/clay and pectin/HEC/clay incorporated with titanium dioxide nanoparticles (TiO
2 NPs) and use the prepared bionanocomposite as microbial disinfectants for real wastewater. Pectin/HEC/clay and pectin/HEC/clay/TiO2 bionanocomposite were characterized by various methods including X-ray diffraction (XRD), scanning electron microscope (SEM), and Fourier-transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA). Mechanical properties and water vapor permeability (WVP) were carried out. The results of SEM showed that, the prepared bionanocomposite had a smooth surface. Additionally, TiO2 nanoparticles to the pectin/HEC/clay composites may lead to changes in the FTIR spectrum. The intensity of XRD peaks indicated that, TiO2 NPs was small size crystallite. TGA illustrated that pectin has moderate thermal stability, while HEC generally exhibits good thermal stability. The TEM showed that, TiO2 nanoparticles have diameters <25 nm. On the other hand, antimicrobial activities of pectin/HEC/clay against Escherichia coli (E. coli), Staphylococcus aureus and Candida albicans have been enhanced by adding TiO2 NPs. The minimum inhibitory concentration (MIC) of pectin/HEC/clay/TiO2 against E. coli was 200 mg/mL. Moreover, complete eradication of E. coli, Salmonella and Candida spp. from real wastewater was observed by using pectin/HEC/clay/TiO2 bionanocomposite. Finally, it can be concluded that, the synthesized bionanocomposite is environmentally friendly and considered an excellent disinfectant matter for removal of the microbial pathogens from wastewater to safely reuse., Competing Interests: Declaration of competing interest The authors hereby declare that the disclosed information is correct and that no other situation of real, potential or apparent conflict of interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
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29. Improvement of interface bonding of bacterial cellulose reinforced aged paper by amino-silanization.
- Author
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Mou H, Wu T, Wu X, Zhang H, Ji X, Fan H, and Song H
- Subjects
- Propylamines chemistry, Hydrogen-Ion Concentration, X-Ray Diffraction, Temperature, Spectroscopy, Fourier Transform Infrared, Cellulose chemistry, Paper, Silanes chemistry
- Abstract
The aging of paper seriously threatens the service life of cultural heritage documents. Bacterial cellulose (BC), which has a good fiber aspect ratio and is rich in hydroxyl groups, is suitable for strengthening aged paper. However, a single BC added was not ideal for paper restoration, since only strengthening was not able to resist the persistent acidification of ancient book. In this work, BC was functionalized by 3-aminopropyltriethoxysilane (APTES) to develop the interface bonding with aged paper. Fourier transform infrared (FTIR), X-ray diffraction (XRD), nuclear magnetic resonance (NMR) and elemental analysis identified the successful amino-silanization of BC. The modification parameters were optimized as the concentration of APTES of 5 wt%, the reaction time of 4 h, and the reaction temperature of 80 °C based on a considerable improvement in the strength properties without obvious appearance impact on reinforced papers. Moreover, the pH value of the repaired paper was achieved at 8.03, ensuring the stability of the anti-aging effect. The results confirmed that APTES-BC had great potential applications in ancient books conservation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. All the authors listed have approved the manuscript enclosed., (Copyright © 2024. Published by Elsevier B.V.)
- Published
- 2024
- Full Text
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30. Enhanced stability and biocompatibility of HIPEs stabilized by cyclodextrin-metal organic frameworks with inclusion of resveratrol and soy protein isolate for β-carotene delivery.
- Author
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Zhang Y, Yu D, Zhao R, Hu F, Li Z, Dong B, Lu P, Song Z, Wang H, Zhang F, Chen W, Liu W, and Li H
- Subjects
- Humans, Biocompatible Materials chemistry, Antioxidants chemistry, Antioxidants pharmacology, Nanoparticles chemistry, Drug Carriers chemistry, Soybean Proteins chemistry, Resveratrol chemistry, Resveratrol pharmacology, beta Carotene chemistry, Emulsions chemistry, Metal-Organic Frameworks chemistry, Cyclodextrins chemistry
- Abstract
High internal phase Pickering emulsions (HIPEs) constitute a significant research domain within colloid interface chemistry, addressing the demand for robust emulsion systems across various applications. An innovative nanoparticle, synthesized from a cyclodextrin metal-organic framework encapsulated with a composite of resveratrol and soy isolate protein (RCS), was employed to fortify a high internal phase emulsion. The emulsion's three-dimensional printing capabilities, alongside the encapsulated delivery efficacy for β-carotene, were thoroughly examined. Cyclodextrin metal-organic frameworks (CD-MOFs), facilitated by cellulose nanofibrils, were synthesized to yield particles at the nanoscale, maintaining a remarkable 97.67 % cellular viability at an elevated concentration of 1000 μg/ml. The RCS nanoparticles demonstrated thermal stability and antioxidant capacities surpassing those of CD-MOF. The integration of soybean isolate protein augmented both the hydrophobicity (from 21.95 ± 0.64° to 59.15 ± 0.78°) and the interfacial tension (from 14.36 ± 0.46 mN/m to 5.34 ± 0.81 mN/m) of the CD-MOF encapsulated with resveratrol, thereby enhancing the RCS nanoparticles' adsorption at the oil-water interface with greater stability. The durability of the RCS-stabilized high internal phase emulsions was contingent upon the RCS concentration. Emulsions stabilized with 5 wt%-RCS exhibited optimal physical and chemical robustness, demonstrating superior performance in emulsion 3D printing and β-carotene encapsulation delivery. This investigation furnishes a novel perspective on the amalgamation of food customization and precision nutrition., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
31. Green synthesis of silver nanoparticles-capped aminated lignin as a robust active catalyst for dye discoloration.
- Author
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Heo JW, Oh DH, Xia Q, Kim MS, and Kim YS
- Subjects
- Catalysis, Water Pollutants, Chemical chemistry, Wastewater chemistry, Silver chemistry, Lignin chemistry, Metal Nanoparticles chemistry, Green Chemistry Technology, Coloring Agents chemistry
- Abstract
Considering the severity of global environmental issues, biomass-derived products have received significant attention as alternatives to foster sustainability and eco-friendliness. The use of metal nanoparticle catalysts for dye decomposition is emerging as a promising approach for environmentally friendly dye removal. In this study, an aminosilane-modified lignin (AML)/silver nanoparticle (AgNP) composite was fabricated and used as a hydrogenation catalyst. The AgNPs were well dispersed on the AML surface and formed strong bonds within the AML/AgNP complex. AML also served as an effective reducing and capping agent for Ag(I) ions. The AML/AgNPs were found to be an efficient catalyst with excellent dye degradation ability and easy reusability. Biomass-derived lignin can be used as a reducing and capping agent for metals and this complex can be used as a high-value bio-catalyst for wastewater remediation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
32. Fabrication and characterization of an alginate-based film incorporated with cinnamaldehyde for fruit preservation.
- Author
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Zhou T, Wang H, Han Q, Song Z, Yu D, Li G, Liu W, Dong C, Ge S, and Chen X
- Subjects
- Food Preservation methods, Food Packaging methods, Anti-Infective Agents pharmacology, Anti-Infective Agents chemistry, Escherichia coli drug effects, Alginates chemistry, Fruit chemistry, Acrolein analogs & derivatives, Acrolein chemistry, Acrolein pharmacology, Antioxidants pharmacology, Antioxidants chemistry
- Abstract
Sodium alginate (SA) is widely used in the food, biomedical, and chemical industries due to its biocompatibility, biodegradability, and excellent film-forming properties. This article introduces a simple method for preparing uniform alginate-based packaging materials with exceptional properties for fruit preservation. The alginate was uniformly crosslinked by gradually releasing calcium ions triggered by the sustained hydrolysis of gluconolactone (GDL). A cinnamaldehyde (CA) emulsion, stabilized by xanthan without the use of traditional surfactants, was tightly incorporated into the alginate film to enhance its antimicrobial, antioxidant, and UV shielding properties. The alginate-based film effectively blocked ultraviolet rays in the range of 400-200 nm, while allowing for a visible light transmittance of up to 70 %. Additionally, it showed an increased water contact angle and decreased water vapor permeability. The alginate-based film was also employed in the preparation of coated paper through the commonly used coating process in the papermaking industry. The alginate-based material displayed excellent antioxidant properties and antimicrobial activity against Escherichia coli, Staphylococcus aureus and Botrytis cinerea, successfully extending the shelf life of strawberries to 7 days at room temperature. This low-cost and facile method has the potential to drive advancements in the food and biomedical fields by tightly incorporating active oil onto a wide range of biomacromolecule substrates., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
33. Active and smart biomass film with curcumin Pickering emulsion stabilized by chitosan-adsorbed laurate esterified starch for meat freshness monitoring.
- Author
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Yang Z, Chen Q, and Wei L
- Subjects
- Antioxidants chemistry, Animals, Swine, Laurates chemistry, Tensile Strength, Adsorption, Meat analysis, Hydrophobic and Hydrophilic Interactions, Hydrogen-Ion Concentration, Curcumin chemistry, Chitosan chemistry, Starch chemistry, Emulsions chemistry, Biomass, Food Packaging methods
- Abstract
The multifunctional active smart biomass film was prepared by incorporating chitosan-adsorbed laurate esterified starch curcumin Pickering emulsion into the starch film matrix, with nano-cellulose serving as reinforcing agents. The mechanical and functional properties of the film were studied, and the film was used to monitor the freshness of pork. The results demonstrated a relatively uniform distribution of curcumin and Pickering emulsion droplets within the film matrix. Furthermore, the thermal stability was minimally impacted by the introduction of curcumin Pickering emulsion, while the tensile strength and tensile strain of the film were increased, and both its hydrophobicity and antioxidant properties were improved. The free radical scavenging rate reached 56.01 %, with sustained high antioxidant capacity even after 8 days. Additionally, the presence of curcumin provided the film with pH indicating ability and delayed pork spoilage. Therefore, this work provides an attractive strategy for constructing green, active, and smart biomass packaging films for meat packaging applications., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
34. Enhanced flexibility of high-yield bamboo pulp fibers via cellulase immobilization within guar gum/polyacrylamide/polydopamine interpenetrating network hydrogels.
- Author
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Hu M, Zhang H, Yang J, Lu B, Cao H, Cheng Z, Lyu X, Liu H, and An X
- Subjects
- Hydrogen-Ion Concentration, Temperature, Sasa chemistry, Plant Gums chemistry, Hydrogels chemistry, Acrylic Resins chemistry, Cellulase chemistry, Cellulase metabolism, Enzymes, Immobilized chemistry, Enzymes, Immobilized metabolism, Indoles chemistry, Polymers chemistry, Galactans chemistry, Mannans chemistry
- Abstract
Softness is a crucial criterion in assessing the comfort and usability of tissue paper. Flexible fibers contribute to the softness of the tissue paper by allowing the sheets to conform to the contours of the skin without feeling rough or abrasive. This study focuses on developing innovative CGG/APAM/PDA hydrogels with interpenetrating networks consisting of cationic guar gum, anionic polyacrylamide, and polydopamine for cellulase immobilization, aimed at improving bamboo fiber flexibility. Cellulase biomolecules are efficiently immobilized on CGG/APAM/PDA hydrogels through the Schiff base reaction. Immobilized cellulases have a wider pH applicability than free cellulases, good storage stability, and can maintain high relative activity at relatively high temperatures. The treatment of bamboo fibers with immobilized cellulase results in a significant increase in flexibility, reaching 6.90 × 10
14 N·m2 , which is 7.18 times higher than that of untreated fibers. The immobilization of cellulases using CGG/APAM/PDA hydrogels as carriers results in a substantial enhancement of storage stability, pH applicability, and inter-fiber bonding strength, as well as the capacity to sustain high relative enzymatic activity at elevated temperatures. The immobilization of cellulase within CGG/APAM/PDA interpenetrating network hydrogels presents a viable strategy for enhancing bamboo fiber flexibility, thereby expanding the accessibility of tissue products., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
- Full Text
- View/download PDF
35. Double domain fusion improves the reverse transcriptase activity and inhibitor tolerance of Bst DNA polymerase.
- Author
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Xiang R, Liu GY, Hou Y, Xie LX, Wang QS, and Hu SQ
- Subjects
- Animals, Recombinant Fusion Proteins genetics, SARS-CoV-2 drug effects, SARS-CoV-2 genetics, Swine, Nucleic Acid Amplification Techniques methods, Protein Domains, DNA-Directed DNA Polymerase genetics, DNA-Directed DNA Polymerase metabolism, Reverse Transcriptase Inhibitors pharmacology, COVID-19 virology, RNA, Viral genetics, RNA-Directed DNA Polymerase metabolism, RNA-Directed DNA Polymerase genetics, African Swine Fever Virus genetics, African Swine Fever Virus enzymology
- Abstract
To enhance the DNA/RNA amplification efficiency and inhibitor tolerance of Bst DNA polymerase, four chimeric Bst DNA polymerase by fusing with a DNA-binding protein Sto7d and/or a highly hydrophobic protein Hp47 to Bst DNA polymerase large fragment. One of chimeric protein HpStBL exhibited highest inhibitor tolerance, which retained high active under 0.1 U/μL sodium heparin, 0.8 ng/μL humic acid, 2.5× SYBR Green I, 8 % (v/v) whole blood, 20 % (v/v) tissue, and 2.5 % (v/v) stool. Meanwhile, HpStBL showed highest sensitivity (93.75 %) to crude whole blood infected with the African swine fever virus. Moreover, HpStBL showed excellent reverse transcriptase activity in reverse transcription loop-mediated isothermal amplification, which could successfully detect 0.5 pg/μL severe acute respiratory syndrome coronavirus 2 RNA in the presence of 1 % (v/v) stools. The fusion of two domains with different functions to Bst DNA polymerase would be an effective strategy to improve Bst DNA polymerase performance in direct loop-mediated isothermal amplification and reverse transcription loop-mediated isothermal amplification detection, and HpStBL would be a promising DNA polymerase for direct African swine fever virus/severe acute respiratory syndrome coronavirus 2 detection due to simultaneously increased inhibitor tolerance and reverse transcriptase activity., Competing Interests: Declaration of competing interest The authors declare that they have no competing financial interest associated with this manuscript., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
36. Carbon-based single-atom catalysts derived from biomass: Fabrication and application.
- Author
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Li J, Wang G, Sui W, Parvez AM, Xu T, Si C, and Hu J
- Subjects
- Catalysis, Metals chemistry, Biomass, Carbon chemistry
- Abstract
Single-atom catalysts (SACs) with active metals dispersed atomically have shown great potential in heterogeneous catalysis due to the high atomic utilization and superior selectivity/stability. Synthesis of SACs using carbon-neutral biomass and its components as the feedstocks provides a promising strategy to realize the sustainable and cost-effective SACs preparation as well as the valorization of underused biomass resources. Herein, we begin by describing the general background and status quo of carbon-based SACs derived from biomass. A detailed enumeration of the common biomass feedstocks (e.g., lignin, cellulose, chitosan, etc.) for the SACs preparation is then offered. The interactions between metal atoms and biomass-derived carbon carriers are summarized to give general rules on how to stabilize the atomic metal centers and rationalize porous carbon structures. Furthermore, the widespread adoption of catalysts in diverse domains (e.g., chemocatalysis, electrocatalysis and photocatalysis, etc.) is comprehensively introduced. The structure-property relationships and the underlying catalytic mechanisms are also addressed, including the influences of metal sites on the activity and stability, and the impact of the unique structure of single-atom centers modulated by metal/biomass feedstocks interactions on catalytic activity and selectivity. Finally, we end this review with a look into the remaining challenges and future perspectives of biomass-based SACs. We expect to shed some light on the forthcoming research of carbon-based SACs derived from biomass, manifestly stimulating the development in this emerging research area., Competing Interests: Declaration of competing interest None., (Copyright © 2024. Published by Elsevier B.V.)
- Published
- 2024
- Full Text
- View/download PDF
37. Enzyme activity test paper with high wet strength and anion adsorption properties fabricated from whole cationized softwood chemical fiber.
- Author
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Zhang H, Zhou M, Jin H, Jia W, Li C, Pan F, and Shi H
- Subjects
- Adsorption, Wood chemistry, Cations chemistry, Paper, Anions chemistry
- Abstract
Paper-based test film material is widely used in a variety of test instruments for different applications. The enzyme activity test paper sheet is one of the most popularly used test papers. Here we present a novel fabrication of paper-based enzyme activity test paper without cationic resin added in. The chemical pulping fibers were first beaten to different degrees (from 14.6 to 41.5°SR) with a PFI beater. After that, the fibers were modified with a cationic agent (3-chloro-2-hydroxypropyl trimethyl ammonium chloride) under the system of alkali and water solution. Finally, the test papers were made with the modified fiber by a regular paper former in lab. The results showed that beating is beneficial for the improvement of the cationization reaction which is indicated by the Zeta potential, FTIR and EDS. The main mechanisms involved are the destruction of crystalline zone, increase of free hydroxyl group and defibrillation. This hypothesis was supported by the SEM, XRD and fiber analyzer. Beating under the optimized condition, the wet strength and liquid absorbability of test paper can meet the application requirement, and the test results of enzyme activity are quite close to those of commercial test papers., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
38. A composite of AgNPs and lignin porous microspheres via in-situ reduction of Ag + and its catalytic performance.
- Author
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Xue S, Lin P, Pang Y, Li Z, Zhou M, Qiu X, and Lou H
- Subjects
- Catalysis, Porosity, Nitrophenols chemistry, Oxidation-Reduction, Kinetics, Lignin chemistry, Silver chemistry, Microspheres, Metal Nanoparticles chemistry
- Abstract
Despite the widespread utilization of nano silver composites in the domain of catalytic hydrogenation of aromatic pollutants in wastewater, certain challenges persist, including the excessive consumption of chemical reagents during the preparation process and the difficulty in recycling. In this study, silver ions were reduced in-situ by taking advantage of the adsorptive and reducing capacities of hydroxyls and amino groups on lignin porous microspheres (LPMs) under mild ultrasonic conditions, and lignin porous microspheres loaded with silver nanoparticles (Ag@LPMs) were conveniently prepared. Ag@LPMs had excellent catalytic and cycling performances for p-nitrophenol (4-NP), methylene blue (MB) and methyl orange (MO). The 4-NP could be completely reduced to 4-AP within 155 s under the catalysis of Ag@LPMs, with a pseudo-first-order kinetic constant of 1.28 min
-1 . Furthermore, Ag@LPMs could still complete the catalytic reduction of 4-NP within 10 min after five cycles. Ag@LPMs with the particle size ranging from 100 to 200 μm conferred ease of recycling, and the porous structure effectively resolved the issue of sluggish mass transfer encountered during the catalytic process. At the same time, the binding force of nano silver and LPMs obtained by ultrasonic was stronger than that of heating, so the materials prepared by ultrasonic had better cycling performance. Silver ions concentration and pH value in the preparation process affected the catalytic performance of Ag@LPMs, 50 mmol/L Ag+ and pH value of 7 turned out to be the optimization conditions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have influenced the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)- Published
- 2024
- Full Text
- View/download PDF
39. Effect of molecular weight of PEI on the strength and hydrophobic performance of fiber-based papers via PEI-KH560 surface sizing.
- Author
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Gao Y, Yang W, Yi W, Ni S, Fu Y, Qin M, and Zhang F
- Subjects
- Silanes chemistry, Surface Properties, Polyethyleneimine chemistry, Molecular Weight, Hydrophobic and Hydrophilic Interactions, Paper
- Abstract
In recent years, researchers have put much attention on the improvements and upgrades of novel wet strength agent in the papermaking fields, especially in the usage of household paper. Herein, PEI
M -KH560 by polyethyleneimine (PEI) and γ-glycidyl ether propyl trimethoxysilane (KH560) was synthesized with five molecular weights (Mw) of PEI at 600, 1800, 10,000, 70,000 and 750,000. Results showed that the molecular weight greatly influenced the physicochemical properties of PEI-KH560, such as the size and thermal stability. The intrinsic cationic charge of PEI-KH560 provided the bonding sites with the paper fibers, forming strengthened fiber-fiber joints. It was shown that the dry, wet strength and hydrophobicity of cellulosic paper sheets were obviously improved. When the m (PEI):m(KH560) is 1:2, the strength of papers after sizing by Mw of PEI at 600 and 1800 is the most obvious, with the dry strength increased by 227.9 % and 187.5 %, and the wet strength increased by 183.8 % and 207.8 %, respectively. The maximum hydrophobicity was found at the PEI1800 -KH560 with the contact angle value of 130.6°. The resultant environmental-friendly agent (PEI-KH560) obtained in this work provides valuable significance for the preparation of household and food packaging paper., Competing Interests: Declaration of competing interest The authors declare that they have no known competing interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
- Full Text
- View/download PDF
40. Halloysite nanotubes enhanced polyimide/oxidized-lignin nanofiber separators for long-cycling lithium metal batteries.
- Author
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Song C, Luo J, Gao C, Peng Q, Gibril ME, Fatehi P, Liu Z, Wang S, and Kong F
- Subjects
- Oxidation-Reduction, Resins, Synthetic chemistry, Lithium chemistry, Nanotubes chemistry, Electric Power Supplies, Nanofibers chemistry, Lignin chemistry, Clay chemistry
- Abstract
The high energy density and robust cycle properties of lithium-ion batteries contribute to their extensive range of applications. Polyolefin separators are often used for the purpose of storing electrolytes, hence ensuring the efficient internal ion transport. Nevertheless, the electrochemical performance of lithium-ion batteries is constrained by its limited interaction with electrolytes and poor capacity for cation transport. This work presents the preparation of a new bio-based nanofiber separator by combining oxidized lignin (OL) and halloysite nanotubes (HNTs) with polyimide (PI) using an electrospinning technique. Analysis was conducted to examine and compare the structure, morphology, thermal characteristics, and EIS of the separator with those of commercially available polypropylene separator (PP). The results indicate that the PI@OL and PI-OL@ 10 % HNTs separators exhibit higher lithium ion transference number and ionic conductivity. Moreover, the use of HNTs successfully impeded the proliferation of lithium dendrites, hence exerting a beneficial impact on both the cycle performance and multiplier performance of the battery. Consequently, after undergoing 300 iterations, the battery capacity of LiFePO
4 |PI-OL@ 10 % HNTs|Li stays at 92.1 %, surpassing that of PP (86.8 %) and PI@OL (89.6 %). These findings indicate that this new bio-based battery separator (PI-OL@HNTs) has the great potential to serve as a substitute for the commonly used PP separator in lithium metal batteries., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
- Full Text
- View/download PDF
41. Designable immobilization of D-allulose 3-epimerase on bimetallic organic frameworks based on metal ion compatibility for enhanced D-allulose production.
- Author
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Tang H, Chen Y, Fan D, Zhao F, and Han S
- Subjects
- Carbohydrate Epimerases chemistry, Carbohydrate Epimerases metabolism, Enzyme Stability, Ions chemistry, Fructose, Metal-Organic Frameworks chemistry, Enzymes, Immobilized chemistry, Enzymes, Immobilized metabolism, Molecular Docking Simulation
- Abstract
D-allulose, a low-calorie rare sugar catalyzed by D-allulose 3-epimerase (DAE), is highly sought after for its potential health benefits. However, poor reusability and stability of DAE limited its popularization in industrial applications. Although metal-organic frameworks (MOFs) offer a promising enzyme platform for enzyme immobilization, developing customized strategies for MOF immobilization of enzymes remains challenging. In this study, we introduce a designable strategy involving the construction of bimetal-organic frameworks (ZnCo-MOF) based on metal ions compatibility. The DAE@MOFs materials were prepared and characterized, and the immobilization of DAE and the enzymatic characteristics of the MOF-immobilized DAE were subsequently evaluated. Remarkably, DAE@ZnCo-MOF exhibited superior recyclability which could maintain 95 % relative activity after 8 consecutive cycles. The storage stability is significantly improved compared to the free form, with a relative activity of 116 % remaining after 30 days. Molecular docking was also employed to investigate the interaction between DAE and the components of MOFs synthesis. The results demonstrate that the DAE@ZnCo-MOF exhibited enhanced catalytic efficiency and increased stability. This study introduces a viable and adaptable MOF-based immobilization strategy for enzymes, which holds the potential to expand the implementation of enzyme biocatalysts in a multitude of disciplines., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
42. Double-drying 3D lamellar-structured aerogel membrane for efficient oil-water separation and long-lasting antibacterial activity.
- Author
-
Tang S, Wu Z, Wei L, Weng J, Luo J, and Wang X
- Subjects
- Gels chemistry, Porosity, Desiccation methods, Hydrophobic and Hydrophilic Interactions, Freeze Drying methods, Anti-Bacterial Agents chemistry, Anti-Bacterial Agents pharmacology, Oils chemistry, Water chemistry, Membranes, Artificial
- Abstract
Conventional oil-water separation membranes are difficult to establish a trade-off between membrane flux and separation efficiency, and often result in serious secondary contamination due to their fouling issue and non-degradability. Herein, a double drying strategy was introduced through a combination of oven-drying and freeze-drying to create a super-wettable and eco-friendly oil-water separating aerogel membrane (TMA
df ). Due to the regular nacre-like structures developed in the drying process and the pores formed by freeze-drying, TMAdf aerogel membrane finally develops regularly arranged porous structures. In addition, the aerogel membrane possesses excellent underwater superoleophobicity with a contact angle above 168° and antifouling properties. TMAdf aerogel membrane can effectively separate different kinds of oil-water mixtures and highly emulsified oil-water dispersions under gravity alone, achieving exceptionally high flux (3693 L·m-2 ·h-1 ) and efficiency (99 %), while being recyclable. The aerogel membrane also displays stability and universality, making it effective in removing oil droplets from water in corrosive environments such as acids, salts and alkalis. Furthermore, TMAdf aerogel membrane shows long-lasting antibacterial properties (photothermal sterilization up to 6 times) and biodegradability (completely degraded after 50 days in soil). This study presents new ideas and insights for the fabrication of multifunctional membranes for oil-water separation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
- Full Text
- View/download PDF
43. Study on the mechanism of lignin non-productive adsorption on cellobiohydrolase.
- Author
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Mou H, Tang L, Wu T, Feng L, and Liu Y
- Subjects
- Adsorption, Kinetics, Hydrolysis, Lignin chemistry, Cellulose 1,4-beta-Cellobiosidase chemistry, Cellulose 1,4-beta-Cellobiosidase metabolism, Eucalyptus chemistry
- Abstract
Enzymatic hydrolysis is important for lignocellulosic biomass conversion into fermentable sugars. However, the nonproductive adsorption of enzyme on lignin was major hinderance for the enzymatic hydrolysis efficiency. In this study, non-productive adsorption mechanism of cellulase component cellobiohydrolase (CBH) onto lignin was specific investigated. Research revealed that the adsorption behavior of CBH on eucalyptus alkali lignin (E
uA ) was affected by reaction conditions. As study on the adsorption kinetic, it was indicated that the adsorption cellulose binding domain (CBD) of CBH onto EuA well fitted with Langmuir adsorption model and pseudo second-order adsorption kinetics model. And the tyrosine site related to the adsorption of CBD onto lignin was proved by the fluorescence and UV spectra analysis. The results of this work provide a theoretical guidance to understanding the nonproductive adsorption mechanism and building method to reduce the adsorption of cellulase on the lignin., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
- Full Text
- View/download PDF
44. The molecular structure, vibrational spectra, solvation effect, non-covalent interactions investigations of psilocin.
- Author
-
Holikulov U, Kazachenko AS, Issaoui N, Kazachenko AS, Raja M, Al-Dossary OM, and Xiang Z
- Abstract
Psilocin, or 4-HO-DMT (or 3-(2-dimethylaminoethyl)-1H-indol-4-ol), is a psychoactive alkaloid substance from the tryptamine family, isolated from Psilocybe mushrooms. This substance is being studied by various research groups because it has a clear therapeutic effect in certain dosages. In this work, the study of the structure and properties of psilocin was carried using theoretical methods: the effects of polar solvents (acetonitrile, dimethylsulfoxide, water, and tetrahydrofuran) on the structural parameters, spectroscopic properties (Raman, IR, and UV-Vis), frontier molecular orbital (FMO), molecular electrostatic potential (MEP) surface, and nonlinear optical parameters (NLO). Theoretical calculations were performed at the B3LYP/6-311++G(d,p) level by the density functional theory (DFT) method. IEFPCM was used to account for solvent effects. The types and nature of non-covalent interactions (NCI) between psilocin and solvent molecules were determined using Atoms in Molecules (AIM), the reduced density gradient method (RDG), the electron localization function (ELF), and the localization orbital locator (LOL). Experimental and calculated FT-IR, FT-Raman, and UV-Vis spectra were compared and found to be in good agreement., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)
- Published
- 2024
- Full Text
- View/download PDF
45. Construction of a pH- and viscosity-switchable near-infrared fluorescent probe and its imaging application.
- Author
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Chen Y, Zong P, Chen Q, Wang X, Luo J, Liu K, and Zhang R
- Subjects
- Hydrogen-Ion Concentration, Viscosity, Animals, Humans, Spectrometry, Fluorescence, Optical Imaging, Fluorescent Dyes chemistry, Fluorescent Dyes chemical synthesis, Zebrafish
- Abstract
Viscosity is a parameter used to measure the fluidity of liquids and a key indicator in evaluating the states of body fluid in biological tissues and lesions. Most traditional detection methods have many drawbacks such as a short emission wavelength and interference by background fluorescence. Inspired by the multiple double bond structure of retinal, a novel pH and viscosity dual-response fluorescent probe (Rh-TR) was constructed in this study. Rh-TR exhibited two emission signals centered at 510 and 660 nm. As the pH of the phosphate-buffered saline increased, the fluorescence at 510 nm increased by about 124-fold, while the change in fluorescence at 660 nm was not obvious. When detecting the change in viscosity using the probe, the fluorescence at 510 nm decreased by about 85 %, while the fluorescence at 660 nm increased by over 20-fold. The probe also showed high selectivity and little toxicity. As demonstrated by the biological imaging experiment, the probe successfully imaged changes in the pH and viscosity of cells and in a live animal model of zebrafish. Considering the unique structure of Rh-TR with retinal and its pH- and viscosity-switchable spectral property, the probe may find further application in detecting viscosity-related diseases and industrial detection., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)
- Published
- 2024
- Full Text
- View/download PDF
46. Ultrahigh humidity-resistance ppb-level formaldehyde sensing at room temperature induced by fluorinated dipole based "umbrella" and "bridge".
- Author
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Lv S, Liu L, Guo L, Mai Z, Chen H, Wang C, Wang F, Li H, Lee YK, Umar Siddiqui AM, Yi Z, Zhou G, and Wang Y
- Abstract
Formaldehyde (HCHO) is a major indoor pollutant that is extremely harmful to human health even at ppb-level. Meanwhile, ppb-level HCHO is also a potential disease marker in the exhalation of patients with respiratory diseases. Higher humidity resistance and lower practical limit of detection (pLOD) both have to be pursued for practical HCHO sensors. In this work, by assembling indium oxide (In
2 O3 ) and fluorinated dipole modified reduced graphene oxide (rGO), we prepared a high-performance room temperature HCHO sensor (In2 O3 @ATQ-rGO). Excellent sensing properties toward HCHO under visible illumination have been achieved, including ultra-low pLOD of 3 ppb and high humidity-resistance. By control experiments and density functional theory calculation, it is indicated that the introduced fluorinated dipoles act as not only an "umbrella" to improve the humidity resistance of the composite, but also a "bridge" to accelerate the electron transport, improving the sensitivity of the material. The significant practicality and reliability of the obtained sensors were verified by in-situ simulation experiments using a 3 m3 test chamber with a humidity control system and by detection of the simulated lung disease patient's exhalation. This work provides an effective strategy of simultaneously achieving high humidity-resistance and low pLOD of room temperature formaldehyde sensing materials., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
- Full Text
- View/download PDF
47. Carbon quantum dots derived from rice straw doped with N and S and its nanocomposites with hydroxypropyl cellulose nanocomposite.
- Author
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Yang X, Lotfy VF, Basta AH, Liu H, and Fu S
- Subjects
- Tensile Strength, Quantum Dots chemistry, Cellulose chemistry, Cellulose analogs & derivatives, Oryza chemistry, Nanocomposites chemistry, Carbon chemistry, Nitrogen chemistry, Sulfur chemistry
- Abstract
As biomass, rice straw (RS) is often valorized as a precursor of green products. In this respect, the RS-based carbon quantum dots (CQDs) are synthesized doped with N and S during the preparation. Synergistic doping with lipoic acid and ethylenediamine can vastly increase the yield of CQD from rice straw from 6.14 % to 62.8 %, and sulfur doping plays a more important role on the surface functional groups of the quantum dots. Further assessment is achieved toward the performance of SN-CQDs-hydroxypropyl cellulose nanocomposites. The optical behavior of synthesized SN-CQDs, and the critical concentration of its liquid crystal behaviors, at which the anisotropic phase begins to emerge, is approximately 1 %. Incorporating it into HPC, especially at 5 %, provided nanocomposite films with effective liquid crystal, tensile strength, and thermal stability. This sample's texture reveals a planar structure with colors ranging from yellow to red. The synergistic effect of incorporating SN-CQDs is shown by improving the strength to ~282.1 %, and the activation energy increased from 583.6 kJ.mol
-1 to 615.1 kJ/mol. HPC-SN-CQDs can be assembled into an LED device, emitting warm light, of which CIE coordinate is (0.34,0.43)., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
- Full Text
- View/download PDF
48. Thermal crosslinking kinetics of shellac and its coating for stiffened and water stable cellulose-based paper straws.
- Author
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Ahuja A, Singh A, and Rastogi VK
- Subjects
- Kinetics, Resins, Plant chemistry, Temperature, Paper, Cellulose chemistry, Water chemistry, Tensile Strength
- Abstract
In this work, shellac and its crosslinking were studied to produce paper straws for the application of liquid products. Commercial paper straws are not durable for liquid foods due to their hygroscopic nature, and thus, they find it challenging to replace single-use plastics. Shellac is a naturally occurring resin utilized as an adhesive and water-resistant coating over the paper straw. Shellac was cured at 125 °C, 150 °C, 175 °C, and 200 °C, and it was crosslinked in about 210 min, 150 min, 60 min, and 30 min respectively and studied for kinetics. The crosslinking of shellac produced a thermally stable material. Compared to commercial paper straws, these paper shellac straws exhibited high bending stiffness (1356.11 Nmm), tensile strength (13,74 MPa), flexural strength (21.72 MPa), and compression strength (24.99 MPa). Moreover, the paper shellac straws didn't bend in wet conditions under load for up to one day, while the commercial paper straw bends in 8 min. Therefore, paper straws with shellac can replace plastic-based straws for a sustainable future., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Arihant Ahuja reports financial support was provided by the Prime Minister Research Fellowship, Ministry of Education, India. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
49. A robust, high-temperature-resistant, protective cellulose gel enabled by multiscale structural engineering.
- Author
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Zhang S, Long Q, Jiang G, Li X, Zhou J, Shao L, Zeng S, and Zhao D
- Subjects
- Hot Temperature, Tensile Strength, Acrylic Resins chemistry, Hydrogen Bonding, Elastic Modulus, Cellulose chemistry, Gels chemistry
- Abstract
Given the escalating environmental and safety concerns, friendly protective materials with exceptional mechanical properties, biodegradability, and insensitivity to high temperature have received more and more attention. Here, we report a robust cellulosic gel through the multi-scale integration of cellulose molecular skeleton, nano-reinforced diatomite, and in situ polymerized polyacrylamide molecule. The bottom-up yet cross-scale approach facilitates the formation of cellulosic gel characterized by a highly interconnected hydrogen bond network and nano-enhanced domain, resulting in a tensile strength of up to 13.83 MPa, a Young's modulus exceeding 280 MPa, and an impact strength around 12.38 KJ m
-1 . Furthermore, this gel exhibits structural stability at temperatures up to 130 °C, good flame retardancy, and complete biodegradability within a span of 35 days. The robust cellulosic gel, acting as a pliable protector, demonstrates exceptional protection for human joints. Our study presents a highly efficient and scalable pathway towards the development of sustainable and robust biomass gels, holding immense potential in intelligent-protective wearables and advanced materials science and engineering., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
- Full Text
- View/download PDF
50. Quantitative analysis of intermolecular forces in cellulose microfibrils and hemicellulose with AFM nano-colloidal probes.
- Author
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Kong Y, Lan X, Zhang W, Leu SY, Hu C, Wang Y, and Fu S
- Subjects
- Colloids chemistry, Nanofibers chemistry, Nanofibers ultrastructure, Microscopy, Atomic Force methods, Polysaccharides chemistry, Cellulose chemistry, Molecular Dynamics Simulation, Xylans chemistry, Microfibrils chemistry, Microfibrils ultrastructure
- Abstract
It is an interesting research topic to study the interfacial interactions between hemicellulose and cellulose, specifically how hemicellulose's structure affects its binding to cellulose nanofibers. Our research proposes that dispersion interaction play an important role in this interfacial interaction, more so than electrostatic forces when considering the adherence of cellulose to xylan. To quantify these interactions, the Atomic Force Microscope (AFM) colloidal probe technique is applied to measure the intermolecular forces between cellulose nanofibers, which are attached to the probe and xylan. These measured forces are then analyzed in relation to the length, diameter and functional groups of the nanocellulose, as well as the molecular weight and side chains of the xylan. Moreover, the predominance of dispersion forces by contrasting the adhesive forces before and after the grafting of a large nonpolar group onto xylan. This modification significantly reduces contact between the cellulose and xylan backbone, thereby markedly diminishing the dispersion interactions. Parallel to the AFM experiments, molecular dynamics (MD) simulations corroborate the experimental results and support our hypotheses. Collectively, these findings contribute to a deeper understanding of polysaccharide interactions within lignocellulose., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
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