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The spatial stochastic simulation of biochemical systems requires significant calculation efforts. Parallel discrete-event simulation is a promising approach to accelerate the execution of simulation runs. However, achievable speedup depends on the parallelism inherent in the model. One of our goals is to explore this degree of parallelism in the Next Subvolume Method type simulations. Therefore we introduce the Abstract Next Subvolume Method, in which we decouple the model representation from the sequential simulation algorithms, and prove that state trajectories generated by its executions statistically accord with those generated by the Next Subvolume Method. The experimental performance analysis shows that optimistic synchronization algorithms, together with careful controls over the speculative execution, are necessary to achieve considerable speedup and scalability in parallel spatial stochastic simulation of chemical reactions. Our proposed method facilitates a flexible incorporation of different synchronization algorithms, and can be used to select the proper synchronization algorithm to achieve the efficient parallel simulation of chemical reactions., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Liquid-encapsulated lysozyme microspheres were successfully synthesized using a sonochemical method. The encapsulation of four different liquids, namely, sunflower oil, tetradecane, dodecane and perfluorohexane on the formation, stability and morphology of the lysozyme microspheres was studied. Among the four different liquids used for encapsulation, perfluorohexane-filled microspheres were found to be most stable in the dried state with a narrow size distribution. In order to explore the possibility of encapsulating biofunctional molecules (e.g., drugs) within these microspheres, liquids containing a fluorescent dye (Nile red) were encapsulated and the ultrasound-induced release of these dye-loaded liquids was studied. The fluorescence data for the liquid-filled lysozyme microspheres demonstrated the potential use of the sonochemical technique for synthesizing these "vehicles" for the encapsulation and the controlled delivery of dyes, flavours, fragrances or drugs.

Heavy metal compounds are used in a variety of industrial processes, including tanning, chrome plating, anti-corrosion treatments, and wood preservation. Heavy metal ion pollution in water and wastewater is often caused by industrial effluent discharge into open water sources. Toxic heavy metal ions such as As (III), Cr (VI), Cd (II), and Pb (II) are well-known and enter the body through a variety of pathways, including the food chain, respiration, skin absorption, and drinking water. These heavy metal ions produce oxidative stress in cells, resulting in cell organelle destruction. Heavy metals produce toxicity and may cause genetic material mutation or change, histone modification, and epigenetic alteration at various stages. Furthermore, heavy metals are linked to heart failure, renal damage, liver failure, and a variety of skin problems. For heavy metals cleanup, several standard approaches are utilized. Nonetheless, these technologies are costly and result in toxic sludge after treatment. As a result, there is an urgent need for an appropriate, environmentally safe, and efficient heavy metal removal technology. For heavy metal removal, microbial-based approaches are regarded as both environmentally benign and cost-effective. This review focuses on heavy metal pollution in water, its harmful consequences, and heavy metal cleanup by microbiological means.

Background: Educational board games have been receiving attention from educators in recent years. Designing the rules of board games based on cognitive theory, and further analysing educational board games from more dimensions are important issues that warrant further study. Purpose: The research designed a board game called Chemistry Story to promote students' learning of the concept of element combination in chemical substances. The design of the cognitive mechanism of the board game was based on three cognitive design principles, namely schema connection theory, attention, and cognitive scaffolding. Sample: The participants were 48 eighth-grade students in Taiwan. Their average age was 13.8. Design and methods: A one-group pretest-posttest design was adopted. The research explored students' learning achievement, flow, and acceptance after using this board game for learning. Moreover, this research analysed the differences in students' flow while playing with game components made of different materials (paper, wood, and plastic), and explored the relationship with learning achievement, perceived usefulness, and perceived ease of use. Results: The results showed that students' concept of element combination in chemical substances improved through playing this board game. In addition, students had considerable engagement and acceptance of the board game's learning activities with the game components made of different materials. The results of the correlation analysis showed that students with low academic achievement were more likely to feel that Chemistry Story was helpful to their studies. It was also found that the wooden material components brought a better sense of engagement and game acceptance. Conclusion: When designing educational board game products, we should not only consider the target knowledge of the board game and the design of the game mechanism, but also consider the students' feelings about the materials used to make the components, and choose materials that can bring students a better learning experience, so as to enhance the positive influence on their learning.

Sulfur-doped biochar (S4BC) was prepared with cherry kernel powder as carbon source, Na2S2O3 as sulfur source and chemical activator. Na2S2O3 can activate biochar through the reaction with carbon, intercalation of alkali metals and the generated gas rushing out of pores, and at the same time, active sulfur atoms are doped into biochar during pyrolysis. The physical and chemical properties of S4BC adsorbent were evaluated by various characterization techniques. The results show that S4BC calcined at 800 °C has huge specific surface area of 959.6 m2/g, developed pore structure, and high content of S (18.84 wt%). Moreover, due to the existence of sulfur and oxygen functional groups, S4BC-800 provides sufficient active sites for the adsorption of Hg2+. According to Langmuir model, the maximum adsorption capacity of S4BC-800 for Hg2+ is 724 mg/g at 313 K, and the adsorption speed is fast with excellent stability and reusability. The microfiltration membrane device based on S4BC-800 can effectively remove the low concentration of Hg2+ in the solution. In this study, a simple method for preparing SBC materials is developed, which is not only of great significance as an adsorbent for Hg2+, but also provides a new choice for the preparation of heteroatom-doped materials.

Water stress significantly affects on rice yield and quality. Eight Japonica varieties from the first and second accumulated temperature zones of Heilongjiang Province were used as materials and four moisture gradients (0, −10, −25 and −40 kPa) were conducted at the grain-filling stage to clarify the effect of water stress on the rice yield and quality in cold regions. The results showed that the rice yield was reduced due to the decrease in the seed setting rate. Rice chalkiness was significantly increased by drought stress, especially under −10 kPa. The protein content of most varieties was significantly reduced and taste quality was increased under −25 to −40 kPa. The effect on protein components increased with increasing drought stress. The gel consistency decreased and the average chain length of amylopectin was less affected by drought. With an increase in moisture deficit, the rapid viscosity analyzer characteristics and chain length distribution of amylopectin showed a trend of first increasing and then decreasing or decreasing and then increasing. The response of starch to mild and severe drought varied. Our study provides a theoretical basis for the efficient utilization of water and high quality and yield of Japonica rice.

Integrating new synthetic methods and experimental techniques from the latest research reports into undergraduate laboratory experiments is of great significance, as it enables students to learn the cutting-edge technology of organic chemistry and cultivates their experimental skills and innovative thinking. In this study, an experiment on their on salt-catalyzed synthesis of chromone [2,3-b] indole derivatives, based on the latest report, was developed to train senior undergraduate students' experimental skills and increase their basic knowledge in organic synthesis, especially those majoring in Organic Chemistry, Applied Chemistry, and Pharmaceutical Chemistry, among others. Incorporating this experiment into laboratory activities can strengthen students' fundamental knowledge of organic chemistry, including Grignard reaction, substitution, addition, carbocation, tautomerism, intramolecular cyclization, and elimination, and enhance their skills in modern organic synthesis techniques, such as Schlenk technology for anhydrous and anaerobic operation, thin-layer chromatography for monitoring reaction progress, and column chromatography for the separation and purification of products. Additionally, this approach can help cultivate students' scientific thinking and creativity and stimulate their enthusiasm for scientific research. The feasibility of introducing this latest scientific achievement into undergraduate laboratory experiments was verified by randomly selecting 12 undergraduates majoring in Applied Chemistry as pretest samples. The assessment results showed that the product yield obtained by different groups of students ranged from 72.6% to 85.8%, indicating a relatively high level of achievement, and the average score of the post-test was 81, which is a satisfactory outcome for such a comprehensive experiment.

Teaching through experiments has always been an indispensable teaching method in chemistry and other STEM disciplines. Letting more students have access to experiments at the frontier of scientific research is essential to stimulating students' interest in chemistry. With the advancement of computer technology, virtual simulation experiments (VSEs) provide a new method to perform chemical experiments for the students who might have no resources to conduct an experiment. Here, a VSE of preparation and test analysis of flexible nanochannel membrane materials is designed by our group at Xiamen University in China, which is an interactive learning platform for studying and practicing experiments reported in the latest scientific articles. The objective pursued herein is to equip students with the appropriate tools and strategies required to perform a dangerous or complex chemical experiment. Multiexperimental paths are designed in different experimental modules and steps to meet students' exploration needs. Our platform suits both on- and off-campus undergraduates or graduates with open access. After practicing 5-6 times, students can gain more professional skills and get higher scores in the test section as the feedback. VSE could become a remote-flexible experimental teaching method with a safer process, lower cost, and wider academic community, especially during the pandemic or in the postpandemic era.

Based on the global goals for cleaner production and sustainable development, the pyrolysis behavior of cephalosporin residues was studied by TG-MS method. The influence of full temperature window on the safe disposal of residues was analyzed based on the “3-2-2” and “1+1” of thermal analysis kinetics, and the gas by-products of thermal degradation were monitored. Results showed that the pyrolysis of distillation residues were divided into low and high-temperature zones, including six stages. Maximum error rate (8.55%) by multiple scan rate was presented based on “3-2-2” pattern and maximum total fluctuation (33.7) by single scan rate was presented based on “1+1” pattern, which implied that the comprehensive multi-level comparison method was very reliable. The E value “E” of six stages showed an increasing trend ranging 166.8 to 872.8 kJ/mol. LgA(mean) was 27.28. Most mechanism function of stage 1, 2 were Z-L-T equation (3D), stage 3, 4, 6 were Avrami-Erofeev equation (AE3, AE4, AE2/3) and stage 5 was Reaction Order (O2). In addition, various small molecular micromolecule substances were detected such as C2H4O, C2H6, NH3, CH4, CO2 under full temperature windows and a possible pyrolysis path of residues was provided.

A Maker-oriented experimental course in general chemistry has been created by using digital tools, such as a computer, a pressure sensor, and data processing software, in combination with a new multiple expansion method and laboratory equipment to determine the vapor pressure precisely. In this Maker chemistry experiment, the pressure sensor measures the pressure inside the chamber and sends the measured pressure value to the microcontroller, which offers a much cheaper and safer alternative than the current triple expansion method while avoiding its inconvenience and frequent failure. Graphing with Origin software provides students with the hands-on experience to appreciate significant chemistry concepts, preparing them for delving further into the subject using data processing software in a scientific inquiry activity. In the multiple expansion method, about 20 sets of data are measured and then processed for data fitting so that more accurate values of vapor pressure and molar heat of evaporation can be obtained, allowing for the better engagement of both first-year undergraduate and high school students.

A scaffolding-based mind tool was designed to allow teachers to easily create lesson plans for in-class gamified activities and to embed various scaffoldings in the lesson plan design. The purpose of this study was to investigate the learning outcomes of a scaffolding-based mind tool integrated with gamified learning activities applied to a science course. The study was conducted to investigate students' learning outcomes, flow, and qualitative feedback on the scaffolding-based mind tool. A total of 134 high school students participated in the experiment. The results showed that the gamified activity with the scaffolding-based mindtool significantly improved students' learning effectiveness, but the learning effectiveness did not differ significantly from that of the students in the lecture-based instruction. In addition, the study found that the learners' flow was high, the students were engaged in the activity. The qualitative feedback analysis also revealed high positive evaluations of the usefulness of the gamified activity, mind tool, and scaffolds. In addition, students with low prior knowledge or low learning effectiveness had significantly higher active engagement in flow than those with high prior knowledge/learning effectiveness.

The utilization of deep learning algorithms for side-scan sonar target detection is impeded by the restricted quantity and representativeness of side-scan sonar (SSS) samples. To address this issue, this paper proposes a method for image augmentation using a CC-WGAN network. First, the generator incorporates the Convolutional Block Attention Module (CBAM) to enhance the assimilation of global information and local features in the input images. This integration also improves stability and avoids mode collapse problems associated with the original Generative Adversarial Network. Subsequently, the CBAM is incorporated into the discriminator to facilitate a better understanding of the relevance and significance of input data, thereby enhancing the model’s generalization ability. Finally, based on this model, existing few-sample SSS images are augmented, and we utilize the augmented images for discrimination and detection with YOLOv5. The experimental results show that following training with the SSS dataset that is augmented by this network, the accuracy of target detection increased by 7.6%, validating the feasibility of our proposed method. This method presents a novel solution to the problem of low model accuracy in underwater target detection with side-scan sonar due to limited samples.

Nonlinear chemical reactions produce interesting chemohydrodynamic patterns in an unstirred medium, which act as interesting demonstrations to display the novel phenomena in a nonequilibrium chemical system. Here, we report new outreach experiments: pH chemohydrodynamic patterns modulated by sodium polyacrylate in the bromate-sulfite-ferrocyanide (BSF) reaction system. In an unstirred Petri dish, transient pH stripe patterns for a bromate-sulfite-ferrocyanide reaction system driven by proton autocatalysis and isothermal density-induced flow can be initiated in the center of approximately two-dimensional Petri dishes by adding a small amount of sulfuric acid solution with a certain concentration. Finally, the transient patterns are restored to the homogeneous high pH state due to proton negative feedback. The addition of sodium polyacrylate can not only lead to horizontal Marangoni flow for forming filamentary pH patterns but also decreases the diffusion of hydrogen ions, which results in a monotonic relationship between the pattern lifetime and polyacrylate concentration. Through these simple, lively and interesting experimental demonstrations, undergraduate students majoring in chemistry can realize the effect of transportations such as diffusion, density-induced flow, and Marangoni flow on complex pattern formation driven by a simple inorganic clock reaction.

In the face of an increasingly severe global climate change situation, carbon neutrality initiatives have been included in the development action plans of many countries around the world. The carbon neutrality vision will also accelerate the revolution in the energy systems of countries around the world, injecting new vitality into the upgrading of industrial structures and high-quality economic growth. The theme of this study is a carbon dioxide capture project learning activity. Through the structured design and model construction of the teaching content, the students' learning style is transformed, and the students' scientific attitude, social responsibility, as well as their ability to use existing knowledge to solve practical problems are cultivated.

Interdisciplinary experiments within chemistry are very important for the improvements in the overall quality of the education received by students. In this work, we describe an interdisciplinary experiment that was successfully completed by undergraduate students. This training integrates multiple disciplines including natural product medicinal chemistry, organic synthesis, and instrumental analysis. The experiment involved the extraction of crude berberine hydrochloride (BBH) from "Coptidis rhizoma," recrystallization for purification, and qualitative and quantitative analysis of purified BBH using the "Brick-L" miniature mass spectrometer (mini-MS). The use of mini-MS analysis is the highlight of this work. Mini-MS offers an unprecedented opportunity to incorporate MS analysis into regular undergraduate teaching due to its small size, low power consumption, and portability. The modular design of the mini-MS instrument used in this work allows instructors to disassemble the instrument on-site in the laboratory to show and introduce the actual structure and components inside the instrument to students. Students not only gain hands-on experience with technology but also have the opportunity to see some of the "inner workings" rather than simply treating the mass spectrometer as "a black box". This greatly helped students understand the construction and analysis principles of MS and motivated students to learn about scientific instruments. This comprehensive experiment can help undergraduate students to improve their overall ability and get in touch with the frontiers of analytical chemistry. This teaching practice can also provide a viable case for comprehensive chemistry experiments in other related disciplines.

The nickel content of nickel-based high-temperature alloy is between 50% and 70%, and the alloy contents of chromium, iron, cobalt, molybdenum, aluminum, titanium and tungsten are within 20%. A method of high resolution plasma mass spectrometry was established to determine the trace elements in nickel-based high-temperature alloy. According to the principle of large isotope abundance, small interference and high sensitivity, the isotopes and resolution of the elements to be measured were optimized, the interferences of most of the multi-atom and double-charged ions were effectively eliminated. The mass spectral interferences of matrix, compositions of alloy and dissolving acid on the trace elements were investigated. The appropriate internal standard of caesium was selected to overcome the matrix effect and reduce the signal drift. Chromium was extracted by methylisobutylone, the extraction efficiency reached up to 99.7%, which eliminated the mass spectral interference of principal component molybdenum in the nickel-based high-temperature alloy. The linear correlation coefficient of the calibration curve was greater than 0.999, and the method detection limit was between 0.002 1 and 0.074 μg/g. The trace elements in the reference material was analyzed, the relative standard deviation (RSD, n=6) was between 2.9% and 7.8%, and the measured value was very consistent with the standard value. This method is simple, fast, accurate and reliable, which can meet the requirement of trace elements determination in nickel-based high-temperature alloy.

Organic–inorganic nanocomposites have the potential to be used in photovoltaic materials due to their eco-friendliness, suitable band gaps, and high stability. In this work, we integrated gold and Fe3O4 magnetic nanoparticles with poly-m-amino benzene sulfonic (m-ABS) to synthesize Fe3O4@Au@poly-(m-aminobenzenesulfonic acid) (Fe3O4@Au@m-ABS) magneto-plasmonic nanoparticles (MPNPs) to enhance the performance of the organic photovoltaic (OPV). These MPNPs exhibit broad UV-Vis absorption and a low band gap of 2.878 eV, enhancing their suitability for photovoltaic applications. The MPNPs were introduced into the ZnO electron transporting layer (ETL) and active layer to investigate the influence of MPNPs on the power conversion efficiency (PCE) of the OPVs. When 0.1 vol% MPNPs were incorporated in the ETL, the OPVs achieved a PCE of 14.24% and a fill factor (FF) of 69.10%. On the other hand, when 0.1 vol% MPNPs were incorporated in the active layer, the OPVs showed a PCE of 14.11% and an FF of 68.83%. However, the OPVs without MPNPs only possessed a PCE of 13.15% and an FF of 63.69%. The incorporation of MPNPs increased the PCE by 8.3% in the OPV device. These findings suggest that Fe3O4@Au@m-ABS MPNPs are promising nanocomposite materials for enhancing the performance of OPVs.

Laboratory spectrometer and hyperspectral imaging camera are two instruments for obtaining spectral information of substances. Both instruments have advantages in practical applications. In this paper, a total of 164 sediment samples were collected from two locations in the marine intertidal zone of Qingdao Aoshan Bay. The total carbon content (TC) concentration in marine sediments was obtained by chemical method. The spectral data of sediments were obtained by the spectrometer and the hyperspectral data were obtained by a hyperspectral imaging camera. With a spectrometer as the main instrument and a hyperspectral imaging camera as the slave instrument, the rapid measurement of carbon content in marine sediments was realized through the model transfer. Two model transfer algorithms were used: piecewise direct standardization, deviation model updating, and slope/bias correction method (PDS-DMP-S/B), and piecewise direct standardization, model updating, and slope/bias correction method (PDS-MP-S/B). Different modeling results were obtained by changing the proportion of the calibration set and test set and adding preprocessing. Compared with the single model transfer algorithm, PDS-MP-S/B and PDS-DMP-S/B were more effective. Standard normal variable transform (SNV) preprocessing had little effect on the modeling results in the model transfer between the spectrometer and hyperspectral imaging camera. After the data normalization of spectral data, all models were improved. When the ratio of the calibration set to the test set was 3:1, the PDS-DMP-S/B algorithm was used for the model transfer, the RP2 value of the modeling result was 0.693, the RMSEP value was 2.332, and the RPD value was 1.615, which achieved a relatively ideal modeling result. This study provides a new and fast method for predicting the carbon content in marine sediments.

Three metal complexes [Cu(HL)Cl](C2H5OH)2] (complex 1), [Ni4L2(CH3COO)4(C2H5OH)4] (complex 2) and [CoHL2] (complex 3) based on 2,3-dihydroxybenzaldehyde-2-(2-aminophenyl)benzimidazole Schiff base (H2L) were synthesized by solvothermal reaction. The three complexes were characterized by FT-IR spectrometer, elemental analysis, thermogravimetric analysis, and X-ray single-crystal diffraction. X-ray single-crystal diffraction analysis confirmed that complex 1 belongs to monoclinic crystal system with P21/c space group, and complex 3 crystallizes in trigonal crystal system with R-3 space group. However, complex 2 crystallized in triclinic crystal system with P-1 space group and exhibits centrosymmetric tetranuclear crystallographic structure. Besides, MTT assay was studied antitumor activities against different tumor cells. The results show that the three complexes all have fine anticancer activities. Among them, complex 2 has significantly better anticancer properties against CNE-2Z cells than that of cisplatin. Finally, apoptosis and cell migration were studied to prove that complex 2 could inhibit tumor cells from proliferating in the manner of apoptosis and migration.

The micron-scale diamond film was prepared using hydrogen and methane as the mixed gas supplies via self-developed 3 kW/2,450 MHz microwave plasma chemical vapor deposition (MPCVD) equipment. On this basis, the evolution of the surface morphology, hydrophobicity, and electrical properties of samples under different hydrogen plasma etching times was investigated. The results indicate that the crystal edge and the top of the diamond grain were preferentially etched when etching time is less than 30 min. The surface roughness reduced from 0.217 to 0.205 μm, and the resistance value decreases from 3.17 to 0.35 MΩ. However, as the etch time increases to 120 min, the etching depth increases, and the surface roughness was increased. Simultaneously, the contact angles increased from 62.8° to 95.9°, which indicates that the surface of the diamond films exhibits more pronounced hydrophobicity. The treatment time of hydrogen plasma has no significant effect on the resistance value in the range of 0.26–0.50 MΩ. The mechanism of surface etching by hydrogen plasma was also discussed.

Curcumin has a wide range of biological activities. This study investigated the anti-inflammatory activity of a triazole curcumin derivative (TAC)—especially its effect on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice and possible targets. In the xylene-induced ear edema experiment, the inhibition rate of TAC against mice ear edema was 23.8%–78.2% over a dose range of 2.5–40 mg/kg 4 h after administration. At a dose of 10 mg/kg, the anti-inflammatory activity of TAC reached a peak at 4 h with an inhibition rate of 73.1%. This was significantly better than the positive control drug sodium diclofenac (DCF). TAC can also effectively reduce the degree of pulmonary edema injury in mice. H&E and Masson staining showed that the inflammatory and pathological indicators of LPS-induced lung injury were significantly improved by TAC. MTT tests illustrated that TAC showed weak cytotoxicity against RAW264.7 cells, and inhibited TNF-α and IL-6 release induced by LPS. Western blotting indicated that TAC decreased the expression of NF-κB and AP-1 in LPS pre-treated RAW264.7 cells, but failed to influence the expression of NF-κB in IL-1β pre-treated HET293T-Myd88−/− cells. Docking studies show that TAC could bind to the hydrophobic pocket of the CD2-TLR4 complex and expressed a high binding affinity. In conclusion, TAC exerts its anti-inflammatory effects by targeting the MD2-TLR4 signaling pathway, thus suggesting that it may be a promising candidate for the treatment of acute lung injury.

Aryldifluoromethyl aryl ethers (ArCF2OAr’) are powerful structural motifs to improve druggability, however, their targeted synthesis remains challenging. Here, the authors report the efficient synthesis of ArCF2OAr’ motifs via nickel-catalyzed aryloxydifluoromethylation with arylboronic acids, and their application in the total synthesis of a difluoromethylated PD-1/PD-L1 immune checkpoint inhibitor with enhanced antitumor efficacy over the non-fluoro congener.

The implementation of targeted therapies for breast cancer has been a challenge. Saikosaponin D (SsD), a triterpene saponin derived from Bupleurum, exhibits potential therapeutic properties for cancer therapy. Here, the role of SsD in broad antiproliferation effects in breast cancer was investigated, and the SsD pharmaceutical efficacy was evaluated by metabolomics analysis. Low (0.4 mg/kg) and high (2.0 mg/kg) concentrations of SsDs were used to treat breast cancer tumors in mice by intraperitoneal injection. Blood samples of mice were collected and the serum samples were extracted after SsD administration for different days. Subsequently, the serum samples were analyzed by ultra-high performance liquid chromatography tandem Orbitrap mass spectrometry (UPLC-Orbitrap MS). According to the “80% rule”, UPLC-Orbitrap MS data were processed and proper ions were screened out for further analysis. Statistical methods including one-way analysis of variance (One-way ANOVA), principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were performed to cross validate the reasonable and accuracy of the models. Representational metabolite ions present significant differences acquired by comparison within/between control group, SsD low concentration group and SsD high concentration group. The results of animal survival experiments demonstrated that SsD had obvious therapeutic effect on tumor. Mice treated with low and high concentrations of SsD showed 60% and 80% survival rate, respectively, with a significant increase in survival compared to untreated control mice. Metabonomic results showed that 12 target metabolite ions including pipecolic acid, N-acryloylglycine, 3-methyleneindolenine, L-kynurenine, phenylethylamine, DL-2-aminooctanoic acid, N (6)-methyllysine, indoleacetaldehyde, 3-methylhistamine, hexanoylglycine, hypoxanthine and hexanoylcarnitine were obtained by intra-group (in control group) screening. The signal intensities of these 12 ions changed significantly in the process of tumor growth, which provided theoretical basis for the study of tumor development and evolution. Meanwhile, 7 important metabolite ions including 3-methylene-indolenine, phenylethylamine, pipecolic acid, L-kynurenine, indoleacetaldehyde, 5-acetylamino-6-formylamino-3-methyluracil and proline betaine were obtained by analyzing inter-group data (compared among three groups), and the first 5 metabolite ions were overlapped with the ions in the list of intra-group screening. Moreover, the biological significances of the selected ions with significant difference were investigated, and two highly correlated manifested metabolic pathways including amino acid metabolism and nucleotide metabolism were discussed. Overall, the results derived from intra-group metabolomic analysis were highly correlated with the inter-group results, and the metabolites along the relevant pathways deserve further attention. This study provides a practical strategy for targeting metabolic analysis using natural product to improve the survival of patients with breast cancer.

An assay combined ultra performance liquid chromatography-quadrupole-time of flight-tandem mass spectrometry (UPLC-Q-TOF MS/MS) with the multivariate statistical analysis methods including principal component analysis and orthogonal partial least squares-discriminate analysis was established for screening and identifying the characteristic markers of cocoa shell relative to cocoa powder, which could be used to quantitatively detect the content of cocoa shell in cocoa powder. The cocoa beans from Ecuador were selected as the research object, and the results showed that there was a great difference between cocoa powder and cocoa shell. One characteristic marker was identified as nigakilactone Ⅰ. There was a good linear relationship between the peak area of nigakilactone Ⅰ and the content of cocoa shell when the content of cocoa shell in cocoa powder was in the range of 1%-50%, the correlation coefficient was greater than 0.999 9. The detection limit and quantitative limit were 0.3% and 1%, respectively. In addition, this method was used for blind sample verification and commercial sample testing. The blind sample verification results showed that the detection content was basically consistent with the actual adulterated content, and the detection content of cocoa shell ranged from 2.51% to 9.03%. This method has high accuracy and high sensitivity, which can be used for identification of commercial cocoa powder adulteration.

Lim kinase (Limk), as an important cytoskeletal regulator, plays an important role in cancer manifestations and neuronal diseases. Limk1 is a member of the Limk family, which is mainly involved in the invasion and metastasis of tumor cells and is abnormally expressed in a variety of cell carcinoma tissues. In this paper, a series of Limk1 inhibitors with aminothiazole skeleton were used to design potent and efficient Limk1 inhibitors by computational approaches. Firstly, the 3D-QSAR model was constructed, and both CoMFA and CoMSIA models have good correlation and prediction ability. The binding requirements between ligand and receptor protein were then further explored through molecular docking, including the critical forces between Limk1 inhibitors and active site residues. Finally, based on the 3D-QSAR model and molecular docking results analysis, three new compounds with theoretically better activity were designed and their ADME properties were predicted.

Even though transition metals can activate Oxone to degrade toxic contaminants, bimetallic materials possess higher catalytic activities because of synergistic effects, making them more attractive for Oxone activation. Herein, nanoscale CuCo-bearing N-doped carbon (CuCoNC) can be designed to afford a hollow structure as well as CuCo species by adopting cobaltic metal organic frameworks as a template. In contrast to Co-bearing N-doped carbon (CoNC), which lacks the Cu dopant, CuCo alloy nanoparticles (NPs) are contained by the Cu dopant within the carbonaceous matrix, giving CuCoNC more prominent electrochemical properties and larger porous structures and highly nitrogen moieties. CuCoNC, as a result, has a significantly higher capability compared to CoNC and Co3O4 NPs, for Oxone activation to degrade a toxic contaminant, Rhodamine B (RDMB). Furthermore, CuCoNC+Oxone has a smaller activation energy for RDMB elimination and maintains its superior effectiveness for removing RDMB in various water conditions. The computational chemistry insights have revealed the RDMB degradation mechanism. This study reveals that CuCoNC is a useful activator for Oxone to eliminate RDMB.

DFT (Density Functional Theory) was applied to calculate the free energy of molecules in order to demonstrate intermolecular dehydration reactions were easier to proceed. Subsequently, the gas phase dehydration of ethylene glycol by the addition of silver (Ag) to the K-ZSM-5 (molecular sieve) in a fixed bed was evaluated. The catalyst showed excellent catalytic performance in the dioxane yield (ca. 77%) at 523 K and in the ethylene oxide yield (ca. 72%) at 623 K. Importantly, the catalyst was recycled several times with no reduction in activity and this method offered a green, efficient, cost effective and environmentally friendly process.

Qilu vacuum residue with Ni + V content of 120 ppm and Ca content of 40 ppm, is hard to process for fixed bed hydrocracking technology. In this work, solvent deasphalting process was used as a pretreatment for processing Qilu vacuum residue, and the yield of deasphalted oil could be up to 48.3 %, with less metal (Ni + V + Ca

Deep eutectic solvents (DESs) are a mixture of hydrogen bond donor (HBD) and hydrogen bond acceptor (HBA) molecules that can consist, respectively, of natural plant metabolites such as sugars, carboxylic acids, amino acids, and ionic molecules, which are for the vast majority ammonium salts. Media such as DESs are modular tools of sustainability that can be pointed toward the extraction of bioactive molecules due to their excellent physicochemical properties, their relatively low price, and accessibility. The present review focuses on the application of DESs for protein extraction and purification. The in-depth effects and principles that apply to DES-mediated extraction using various renewable biomasses will be discussed as well. One of the most important observations being made is that DESs have a clear ability to maintain the biological and/or functional activity of the extracted proteins, as well as increase their stability compared to traditional solvents. They demonstrate true potential for a reproducible but more importantly, scalable protein extraction and purification compared to traditional methods while enabling waste valorization in some particular cases.

In this study, the nanocomposites from biomass (soybean straw) and layered double hydroxides (LDHs), denoted as B/LDHs, were fabricated using the mechanical-hydrothermal method. The obtained B/LDHs nanocomposites were characterized by TEM, SEM, FT-IR, and N2 adsorption–desorption techniques. Adsorption of the heavy-metal ions Pb(ii) on the B/LDHs was determined at 25°C and pH 6.0 using a batch technique. The experimental results demonstrated that biomass contributed to the sorption process. The pseudo-second-order, Langmuir, and Freundlich models well fitted the sorption process, indicating chemisorption and monolayer adsorption were the main adsorption mechanisms. Meanwhile, it is found that there is an obvious effect of adsorbent concentration in the studied adsorption system. In comparison with soybean straw and Mg–Al LDHs, the B/LDHs nanocomposites exhibit significantly enhanced sorption capacities. It is evident from this study that the construction of B/LDHs nanocomposites is an effective strategy for improving the sorption capacity of LDHs, and the modified LDH-based adsorbent shows a good potential in the removal of heavy metals from water. More importantly, it solves the problem of a large number of agricultural waste disposals. And, it achieved the goal of a win-win situation.

Plant-esterase (EC 3.1.1.X) has received much attention because plant esterase and acetylcholinesterase (AChE) share a similar sensitivity towards organophosphorus (OP) pesticides detection with the same inhibition mechanism. To improve the analytical performance, tetraphenyl metal porphyrin, as an indicator was introduced to combine with plant-esterase. The time of reach equilibrium in PBS solution was shortened after adding plant-esterase by assaying the intensify change of the porphyrin spectrum. Meanwhile, intensify of porphyrin spectrum with plant-esterase was increased compared with that of only the porphyrin spectrum in solution. Tetraphenyl metal porphyrin, such as cobalt(II) meso-tetraphenyl porphyrin, is a mixed reversible inhibitor of plant-esterase from kinetic parameters. The combination ratio of plant-esterase and porphyrin is 2:1. On the other hand, the interaction between CoTPPCl and plant-esterase is the strongest among all tested tetraphenyl metal porphyrin. And the mixed system (CoTPPCl-plant-esterase) showed the best sensitivity towards the tested pesticide. All these results indicated that a complex system composed of tetraphenyl metal porphyrin and plant-esterase was fit for detecting pesticides. They make meaningful guidance on the further design of sensing material in monitoring pesticides.

Lignin was used to study the mechanical properties and thermal stability of polymers. The lignin was blended with three kinds of polymers, and the addition of lignin was 0.5 wt%. Under the condition of thermal oxidation, the thermal stability of lignin/polymer samples varies with the structure of lignin. The effects of lignin on the mechanical properties and thermal stability of the polymers were investigated by oxidation induction time (OIT), rheological properties, mechanical properties and differential scanning calorimetry (DSC). The results show that the effect of lignin on the thermal properties of polymer samples is 2~3°C. It can be inferred that lignin can effectively improve the interaction between polymer molecular chain segments, and improve the crystallization rate and rigidity to a certain extent, so it can be seen that lignin has good compatibility and thermal stability.

This study aims to prepare ultrasound-targeted glial cell-derived neurotrophic factor (GDNF) retrovirus-loaded microbubbles (M pLXSN-GDNF) to verify the properties of the microbubbles and to study the therapeutic effect of the GDNF retrovirus-loaded microbubbles combined with ultrasound (U) to open the blood–brain barrier (BBB) in a Parkinson’s disease (PD) model in rats, allowing the retrovirus to pass through the BBB and transfect neurons in the substantia nigra of the midbrain, thereby increasing the expression of GDNF. The results of western blot analysis revealed significant differences between U + MpLXSN-EGFP, U + M + pLXSN-GDNF, and M pLXSN-GDNF (P < 0.05) groups. After 8 weeks of treatment, the evaluation of the effect of increased GDNF expression on behavioral deficits in PD model rats was conducted. The rotation symptom was significantly improved in the U + MpLXSN-GDNF group, and the difference before and after treatment was significant (P < 0.05). Also, the content of dopamine and the number of tyrosine hydroxylase-positive (dopaminergic) neurons were found to be higher in the brain of PD rats in the U + M pLXSN-GDNF group than in the control groups. Ultrasound combined with GDNF retrovirus-loaded microbubbles can enhance the transfection efficiency of neurons in vivo and highly express the exogenous GDNF gene to play a therapeutic role in PD model rats.

The current work described the preparation of gold nanoparticles (AuNPs) using the plant extract of Impatiens balsamina followed by evaluating their wound-healing potential. The formed NPs were studied by performing UV-visible spectroscopy, Fourier transform infrared, transmission electron microscopy and X-ray diffraction. Further, both the thermal and excision wound models were used to understand the wound-healing ability of AuNPs. It is exhibited that at a concentration of 20 mg, the AuNPs exhibited substantial decrease in excision wound within 8 days. The obtained wound-healing results indicated that the AuNPs prepared from the leaf extract of I. balsamina exhibited active wound-healing potential when related to traditional drugs; hence, AuNPs could have future applications in the development of dressing materials in nursing care for wound healing after surgery.

In this paper, maleic anhydride (MA) was grafted onto methyl cellulose (MC) and then reacted with acrylic acid to synthesize a high gel strength and fast water absorption resin (AA-co-MC-g-MA) by UV polymerization. The reaction conditions of maleylated methylcellulose (MC-g-MA) were investigated, including the ratio of MC to MA, reaction time and catalyst amount. In addition, the reaction conditions for the synthesis of super absorbent resin were as follows: the amount of MC-g-MA, the degree of substitution of MC-g-MA, polymerization time, and the amount of initiator. Under optimal conditions, the maximum water absorption volume of synthetic resin was 2116 g/g, and the maximum salt absorption rate was 139 g/g. The water absorption resin prepared this time had high water absorption, water retention, excellent pH sensitivity, etc. It was hoped that it will have a good application prospect in the field of industrial production and agriculture in the future.

In this paper, the effects of coupling agent and lignin extracted from waste cotton stalks in Xinjiang on thermal-oxygen aging properties of polypropylene (PP) composites were studied. The melt index test and indoor thermal oxygen aging test was carried out on the samples treated with coupling agent. The mechanical properties, surface micromorphology, rheological properties and element composition of the materials before and after 30 days of aging were studied. The results showed that the titanate coupling agent was the best for improving the melt index and mechanical properties of PP/cotton stalk lignin composites. After the 30-day thermal oxygen aging test, the samples with 2% lignin had the best impact strength and retention rate of fracture elongation, reaching 68.9% and 77.3% respectively. The sample with 3% lignin content had the smoothen surface, no crack appeared. After aging, the increase of C=O was the least, and the crystal peak area decreased less.

With its excellent electrical and mechanical properties and the rapid development of its device fabrication technologies, laser-induced graphene (LIG) has played an important role in the field of wearable technologies since its discovery in 2014. In recent years, with the relentless development of wearable devices, newly developed LIG-based wearable devices also possess multifunction and intelligence characteristics. This review is aimed toward two of the most important fields related to the development of LIG, namely, health care and human–computer interaction (HCI). We introduce multifunctional and intelligent LIG-based wearable systems for health care and HCI developed over the recent years, sorting out their design ideas, preparation process, performance, and application. Furthermore, we discuss the future development direction of LIG-based wearable systems for health care and HCI.

We evaluate the effectiveness of companion classes designed to support at-risk first-year students in introductory biology and chemistry within the University of California system. Companion classes (co-classes) are optional classes associated with large, gateway biology and chemistry courses (parent classes) and provide three hours of instruction each week; two hours are devoted to content reinforcement, and one hour is devoted to advising. Recruitment into co-classes was focused on students who had attended high schools with high proportions of low-income families, English language learners, and foster youth. Co-classes incorporate pedagogical elements from multiple first-year initiatives but are distinguished by having content support and advising that address sociopsychological factors frequently identified as barriers to student success. Average recruitment into co-class sections was 20.8%. Multivariate regression, Heckman modeling, and propensity score matching showed positive effects on student performance with gains between 4-5% of parent course points. Challenges in implementation are discussed, and student perspectives of co-class benefits are presented.

As cobalt (Co) has been the most useful element for activating Oxone to generate SO4•−, this study aims to develop a hierarchical catalyst with nanoscale functionality and macroscale convenience by decorating nanoscale Co-based oxides on macroscale supports. Specifically, a facile protocol is proposed by utilizing Cu mesh itself as a Cu source for fabricating CuCo2O4 on Cu mesh. By changing the dosages of the Co precursor and carbamide, various nanostructures of CuCo2O4 grown on a Cu mesh can be afforded, including nanoscale needles, flowers, and sheets. Even though the Cu mesh itself can be also transformed to a Cu-Oxide mesh, the growth of CuCo2O4 on the Cu mesh significantly improves its physical, chemical, and electrochemical properties, making these CuCo2O4@Cu meshes much more superior catalysts for activating Oxone to degrade the Azo toxicant, Acid Red 27. More interestingly, the flower-like CuCo2O4@Cu mesh exhibits a higher specific surface area and more superior electrochemical performance, enabling the flower-like CuCo2O4@Cu mesh to show the highest catalytic activity for Oxone activation to degrade Acid Red 27. The flower-like CuCo2O4@Cu mesh also exhibits a much lower Ea of Acid Red 27 degradation than the reported catalysts. These results demonstrate that CuCo2O4@Cu meshes are advantageous heterogeneous catalysts for Oxone activation, and especially, the flower-like CuCo2O4@Cu mesh appears as the most effective CuCo2O4@Cu mesh to eliminate the toxic Acid Red 27.

90Sr (t1/2 = 28.8 a), one of the most significant fission products in high-level radioactive liquid waste (HLLW), contributes to a large part of the heat load and radiation. Removal of 90Sr from the HLLW is beneficial for the final treatment of nuclear waste. In this paper, the extraction of Sr2+ was carried out using dicyclohexano-18-crown-6 (DCH18C6) in a variety of diluents including conventional organic solvents and novel ionic liquid solvents. The effect of several factors, such as nitric acid concentration, crown ether concentration and initial strontium concentration on the extraction of Sr2+ have been studied comprehensively. The higher distribution ratio and the stripping efficiency of Sr2+ were obtained with the binary diluents consisted of n-octanol and acetylene tetrachloride, which were compared with that using pure n-octanol as diluent. As for the CnmimNTf2 (n = 2, 4, 6) ionic liquid solvent systems, the distribution ratio of Sr2+ was much higher in the nitric acid medium with low concentration than in the traditional solvent systems. The results showed that DC2mimNTf2 > DC4mimNTf2 > DC6mimNTf2, which indicated that shorter carbon chain benefits the extraction of Sr2+.

This pot experiment was to evaluate how salts (NaCl, Na2SO4) and alkali (Na2CO3+NaHCO3) affect the physiological and biochemical characteristics during the seedling stage of two cotton cultivars (salt-tolerant, L24; salt-sensitive, X45). Salt and alkali stress reduced seedling emergence rate, relative biomass, and chlorophyll content, however, the REC and MDA content increased. Salt and alkali stress increased markedly superoxide dismutase (SOD) activity. Peroxidase (POD) activity increased first and then decreased as the increase of salt and alkali stress. Catalase (CAT) activity initially increased and then decreased as NaCl stress increased. In addition, the SOD activity, REC, and MDA content was markedly higher in salt stress than that in alkali stress. The proline content of L24 was higher than that of X45 under salt and alkali stress. However, glycine betaine and soluble sugar content of L24 was lower than that of X45 under alkali stress. The REC and MDA content of L24 were lower than those of X45, however, the relative biomass, chlorophyll content, SOD, POD, CAT, and Pro were higher than those of X45. In conclusion, salt tolerant cotton cultivars may possess a superior protection effect by increasing antioxidant enzymes activity under salt and alkali stress.

Roof rocks in coal mines are subjected to the combination of in situ stresses and dynamic stresses induced by mining activities. Understanding the mechanical properties of roof rocks under static and dynamic loads at medium strain rates is of great significance to revealing the mechanism of rock bursts. In this study, we employ the digital image correlation (DIC) technique to investigate the energy concentration and dissipation behaviors, failure mode, and deformation characteristics of roof rocks under combined static and dynamic loads. Our results show that both the static pre-stress and dynamic loading rate have significant effects on the uniaxial compressive strength of rock specimens. From the energy principle, when the static pre-stress is the same, both elastic strain energy density and dissipated energy density increase with increasing dynamic loading rate. The hazard of rock bursts increases with decreasing static pre-stress and increasing dynamic loading rate. At higher dynamic loading rates, more cracks are generated, and the failure becomes more violent. The crack initiation, propagation and coalescence processes are identified, and the failure mode is closely related to the evolution of the global principal strain field of the rock specimens.

Four neoantimycins H-K (1–4) with C1-keto, including the new ones (1–2), were isolated from the culture of Streptomyces conglobatus RJ8. After enzymatically converting into their respective reduced type derivatives (5–8) in vitro, the absolute structures of 1–8 were established/reconfirmed by analyzing hydrolyzed components. The obtained NATs (4, 7, and 8) exhibited excellent cytotoxicity against drug-resistant colon and gastric cancer cells but low toxicity in the noncancerous cell. Further SAR investigation suggested that C1-hydroxyl, C9-isobutyl, and N-formyl contribute to the antiproliferation remarkably.

A Faraday rotation isolator is conventionally achieved by connecting a matched load to a three-port circulator. It obtains superior performance (isolation > 20 dB) at the inevitable cost of non-ideal size. In order to adapt to the miniaturizations and integrations required for future 5G communication systems, it is particularly important to reduce the size of the devices. This work demonstrates a photonic crystal-based isolator design, comprising a unique reflecting cavity and a built-in fan-shaped coupler, where four Ni–Zn ferrite posts achieve the rotations. The design with the compact size of about 46.6 × 41.6 × 4.32 mm3 obtains excellent forward transmission efficiency and reverse isolation of 0.50 dB and 44.20 dB, respectively.

By the method of 1H NMR prescreening and tracing the diagnostic signals, 6-methylpyridinone derivatives, (8R,9S)-dihydroisoflavipucine (1), (8S,9S)-dihydroisoflavipucine (2), 3-(1-hydroxy-4-methyl-2-oxopentylidene)-6-methylpyridine-2,4(1H,3H)-dione (3), 4-hydroxy-3-(2-hydroxy-4-methylpentanoyl)-6-methylpyridin-2(1H)-one (4), 4-hydroxy-3-[(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)methyl]-6-methylpyridin-2(1H)-one (5) and a known 6-methylpyranone derivative 3,3′-methylenebis(4-hydroxy-6-methyl-2H-pyran-2-one) (6) were isolated from the marine fungus Leptosphaerulina sp., which was collected from the starfish Acanthaster planci from the South China Sea. Compounds 2 and 3 are new compounds. Their structures were elucidated on the basis of MS, 1D and 2D NMR, and X-ray single crystal diffraction data. The absolute configurations of compounds 1 and 2 were determined by analysis on the experimental circular-dichroism spectra.

A simple, affordable hydrogen proton exchange membrane (PEM) fuel cell laboratory was developed through a collaborative effort between faculty and undergraduate students at Brown University. It has been incorporated into the introductory chemistry curriculum and successfully implemented in a class of over 500 students per academic year for over 3 years. This laboratory involves a PEM fuel cell that uses hydrogen gas to power a small cell phone vibrator and a model car. The lab highlights electrochemical and thermodynamic concepts while illuminating how hydrogen fuel cells generate clean energy without polluting the environment. Hydrogen fuel is generated by the in situ electrolysis of water, and the chemical energy of the fuel and oxidant is then converted into electrical energy that can do work. A circuit board with a mini cell phone vibrator and a resistor built onto a model fuel cell car enables students to make a series of electrical measurements in addition to observing the car or mini cell phone vibrator run. Through simple electric measurements, thermodynamic parameters such as Gibbs's free energy and the efficiency of the hydrogen fuel cell can be calculated. This laboratory is designed to spark students' interest and to expose them to a real-world application of electrochemistry.

The composite hydrogels based on N,N’-dimethylamino ethyl methacrylate (DMAEMA) and polyethyleneimine (PEI) were prepared by amino radical polymerization and confirmed by Fourier Transform Infrared Spectra (FTIR) and elemental analysis. Then adsorption behavior and mechanism of Cr(VI) ions on the obtained materials were investigated with scanning electron microscope, Zeta potential and thermal gravity analysis, etc. The adsorption process was found to follow the pseudo-second order kinetics and Langmuir model, and the maximum adsorption capacity of Cr(VI) ions reached 122.8 mg g-1. X-ray photoelectron spectroscopy (XPS) and pH analysis revealed that the Cr(VI) ions were adsorbed into the gels through electrostatic interaction mechanism, and SO42- in the solution had a great effect on the adsorption process. In addition, high pH and ionic strength could reduce the uptakes of adsorbate, which could be used for desorption of Cr(VI) ions from the gels.