1,447 results on '"C. M. Zheng"'
Search Results
2. Develop Inverse Models to Track Environmental Pollutants Using Mass Conservation Law for Both Normal and Anomalous Transport
- Author
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H. G. Sun and C. M. Zheng
- Subjects
Pollutant ,Environmental science ,Inverse ,Atmospheric sciences ,Track (rail transport) ,Conservation of mass - Published
- 2018
- Full Text
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3. [The bisphenol A-enhanced activity of thyroid carcinoma cell line B-CPAP is inhibited by Icarrin]
- Author
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C M, Zheng, X Z, Liu, Q L, Li, J F, Wang, Z, Tan, and M H, Ge
- Subjects
Flavonoids ,Superoxide Dismutase ,Apoptosis ,Histones ,Glucosides ,Phenols ,Proto-Oncogene Proteins c-bcl-2 ,Cell Line, Tumor ,Malondialdehyde ,Humans ,Thyroid Neoplasms ,Benzhydryl Compounds ,Reactive Oxygen Species ,Cell Proliferation - Published
- 2017
4. Stability prediction in radial immersion for milling with symmetric structure
- Author
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Junz Jiunn-jyh Wang and C. M. Zheng
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Engineering ,Symmetric structure ,business.industry ,Mechanical Engineering ,Mathematical analysis ,Characteristic equation ,Stability diagram ,Numerical models ,Industrial and Manufacturing Engineering ,Control theory ,Immersion (mathematics) ,Coefficient matrix ,business ,Eigenvalues and eigenvectors ,Eigendecomposition of a matrix - Abstract
In this study, an analytical approach is presented to find stability limits in terms of radial immersion for a given axial depth of cut, and vice versa. Under the assumption of axis-symmetric structure and using the zero order force model, the direction coefficient matrix is decoupled to reduce the 2D milling system to a 1D stability problem. The effect of the radial immersion and radial cutting coefficient on the system stability are explicitly represented through the eigenvalue function of the directional coefficient matrix. The resulting characteristic equation allows the limiting radial immersion be solved for a given axial immersion. A procedure is presented in obtaining the radial stability diagram, in which additional unstable island and secondary lobes are shown to exist besides the traditional lobes. Stability diagrams in both axial and radial immersion are presented to demonstrate the physical insights offered by the presented method. The model is validated by comparing with results from the existing analytical and numerical models.
- Published
- 2013
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5. Effects of high concentrations of soil arsenic on the growth of winter wheat (Triticum aestivum L) and rape (Brassica napus)
- Author
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Qiling Tan, C. M. Zheng, Xuecheng Sun, Q. J. Liu, Chengxiao Hu, and J. J. Su
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biology ,Phosphorus ,Crop yield ,Brassica ,food and beverages ,Soil Science ,chemistry.chemical_element ,04 agricultural and veterinary sciences ,010501 environmental sciences ,biology.organism_classification ,01 natural sciences ,Bioavailability ,Animal science ,chemistry ,Agronomy ,Shoot ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Phytotoxicity ,Arsenic ,0105 earth and related environmental sciences ,Sprouting - Abstract
Soil arsenic (As) levels are particularly high in parts of China, where wheat and rape are widely grown. Understanding the effects of As concentration on the growth of these two major crops is of significance for food production and security in China. A pot experiment was carried out to study the uptake of As and phosphorus (P), and the soil As bioavailability at different growth stages of wheat and rape. The results indicated that winter wheat was much more sensitive to As stress than rape. Wheat yields were elevated at low rates of As addition (< 60 mg/kg) but reduced at high rates of As concentrations (80–100 mg/kg); while the growth of rape hadn’t showed significant re sponses to As addition. Phosphorus concentrations in wheat at jointing and ear sprouting stages increased with increasing soil As concentrations, and these increases were assumed to contribute a lot to enhanced growth of wheat at low As treatments. Arsenic did not significantly affect P concentrations in rape either. The highest As concentra tions in wheat shoot and rape leaf were 8.31 and 3.63 mg/kg, respectively. Arsenic concentrations in wheat and rape grains did not exceed the maximum permissible limit for food stuffs of 1.0 mg/kg. When soil As concentration was less than 60 mg/kg, both wheat and rape could grow satisfactorily without adverse effects; when soil As concentra tion was 80–100 mg/kg, rape was more suitable to be planted than wheat.
- Published
- 2012
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6. Identification of cutter offset in end milling without a prior knowledge of cutting coefficients
- Author
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C. M. Zheng and Jiunn-Jyh Junz Wang
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Engineering ,Offset (computer science) ,Computer simulation ,business.industry ,Mechanical Engineering ,End milling ,Shear force ,Structural engineering ,Chip ,Industrial and Manufacturing Engineering ,symbols.namesake ,Machining ,Fourier analysis ,symbols ,business ,Shearing (manufacturing) - Abstract
This paper presents a method for the identification of cutter offset through milling force without requiring the specific cutting coefficients to be known as priori. The total milling force in the presence of cutter offset is first obtained on the basis of dual cutting mechanisms, where the local force is comprised of a constant plowing force and a linear shearing force proportional to the chip load under the cutter offset. The total milling force is synthesized through convolution and is shown to be the sum of three force components: the nominal chip shearing force component, the plowing force components and the offset related shearing force component. Fourier analysis of these force components reveals the effects of offset geometry and yields formulas for the identification of offset geometry. The identification process requires only two cutting tests and the evaluation of two algebraic expressions; the shearing constants are found from the average forces of cutting tests and the offset geometry is identified from the force component at the spindle frequency. Through numerical simulation and experimental results, the efficacy of the identification method is demonstrated; the effects of feed per tooth and cutting depths on the accuracy of the model are investigated and criteria for the appropriate selection of these parameters are suggested.
- Published
- 2003
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7. Online Identification of Shearing and Plowing Constants in End Milling
- Author
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Junz Jiunn-jyh Wang and C. M. Zheng
- Subjects
Shearing (physics) ,Engineering ,business.industry ,Mechanical Engineering ,End milling ,System identification ,Mechanical engineering ,Mechanics ,Industrial and Manufacturing Engineering ,Computer Science Applications ,symbols.namesake ,Die cutting ,Machining ,Control and Systems Engineering ,Fourier analysis ,Frequency domain ,symbols ,business ,Fourier series - Abstract
Online methods for the identification of shearing and plowing cutting constants from forces in a single milling operation are presented. By virtue of the analytical nature of the milling force model in the frequency domain, the shearing and plowing constants are expressed, in a linear closed-form equation, in terms of cutter geometry, cutting depths and the Fourier coefficients of the milling forces. Two methods are presented to identify these cutting constants. The first method uses only the first harmonic components of the milling forces, and the second method utilizes the average forces as well as the ratio of the first harmonic forces. Limitations on the cutting conditions for each identification method are discussed. The accuracy and consistency of these two methods in extracting the shearing and plowing constants from a single set of force measurements are verified through simulation and milling experiments.
- Published
- 2003
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8. Estimation of in-process cutting constants in ball-end milling
- Author
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Jiunn-Jyh Junz Wang and C. M. Zheng
- Subjects
Engineering ,business.industry ,Mechanical Engineering ,Mathematical analysis ,System identification ,Mechanical engineering ,Work in process ,Industrial and Manufacturing Engineering ,Differential geometry ,Machining ,Cutting force ,Ball (bearing) ,business ,Shearing (manufacturing) ,Fourier series - Abstract
Two methods are presented for the estimation of tangential, radial and axial cutting coefficients for the shearing and ploughing mechanisms from a single set of cutting forces in ball-end milling. These estimation methods are based upon the invertibility of the analytical milling force model, which considers both the shearing and the ploughing mechanisms by incorporating their respective cutting constants in the local force model. The periodic milling forces are established as the convolution integral of the differential local cutting forces and their Fourier coefficients are derived and expressed in a matrix expression as a linear function of the unknown cutting constants in terms of cutting conditions and cutter geometry. This linear expression thus leads to a systematic formulation of the estimation methods allowing the six unknown cutting constants to be determined from the measured milling forces. The first method uses the first harmonic forces as the source signal while the second method extracts the six cutting constants from the average force as well as the first harmonics. Limitations of both estimation methods are discussed. The consistency and accuracy of the estimated cutting constants are confirmed by the experimental results.
- Published
- 2003
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9. An analytical force model with shearing and ploughing mechanisms for end milling
- Author
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C. M. Zheng and Jiunn-Jyh Junz Wang
- Subjects
Shearing (physics) ,Engineering ,business.industry ,Mechanical Engineering ,Shear force ,Mechanical engineering ,Mechanics ,Industrial and Manufacturing Engineering ,Shear (sheet metal) ,Superposition principle ,symbols.namesake ,Fourier transform ,Machining ,Frequency domain ,symbols ,business ,Linear combination - Abstract
An analytical force model with both shearing and ploughing mechanisms is established for the end milling processes. The elemental forces are defined as the linear combination of shearing and ploughing forces in six cutting constants. The analytical model for the total milling forces in the angular and frequency domain are derived by convolution approach and Fourier transform respectively and are expressed as the superposition of the shearing force component and ploughing force component. This dual-mechanism model is analyzed and discussed in the frequency domain and compared with the lumped shear model. An expression is derived for identifying the cutting constants of the dual-mechanism model from the average milling forces. Explicit inclusion of ploughing force in the model is shown to result in better predictive accuracy and yields a linear force model with constant cutting coefficients. Experiments verify the accuracy and the frequency analysis of the dual-mechanism model and show that cutting constants for the dual-mechanism model are fairly independent of chip thickness.
- Published
- 2002
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10. Identification of shearing and ploughing cutting constants from average forces in ball-end milling
- Author
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C. M. Zheng and Jiunn-Jyh Junz Wang
- Subjects
business.product_category ,Materials science ,business.industry ,Depth of cut ,Mechanical Engineering ,End milling ,Mechanics ,Structural engineering ,Dual mechanism ,Industrial and Manufacturing Engineering ,Plough ,Machining ,Cutting force ,Ball (bearing) ,business ,Shearing (manufacturing) - Abstract
This paper presents an analytical model for the direct identification of global shearing and ploughing cutting constants from measured average cutting forces in ball-end milling. This model is based on the linear decomposition of elemental local cutting forces into a shearing component and a ploughing component. Then, a convolution integral approach is used to obtain the average cutting forces leading to a concise and explicit expression for the global shearing and ploughing cutting constants in terms of axial depth of cut, cutter radius and average milling forces. The model is verified by comparisons with an existing force model of variable cutting coefficients. Cutting constants are identified through milling experiments and the prediction of cutting forces from identified cutting constants coincides with the experimental measurements. A model for identifying the lumped shearing constants is obtained as a subset of the presented dual mechanism model. Experimental results indicate that a model with dual-mechanism cutting constants predicts the ball-end milling forces with better accuracy than the lumped force model.
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- 2002
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11. A Dual Effect Additive Modified Electrolyte Strategy to Improve the Electrochemical Performance of Zinc-Based Prussian Blue Analogs Energy Storage Device.
- Author
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Xiong Q, Xiong C, Zhou Q, Shen M, Song J, Zhao M, Zhang Y, An M, and Ni Y
- Abstract
Prussian blue analogs (PBA) exhibit excellent potential for energy storage due to their unique three-dimensional open framework and abundant redox active sites. However, the dissolution of transition metal ions in water can compromise the structural integrity of PBAs, leading to significant issues such as low cycle life and capacity decay. To address these challenges, we proposed a dual-effect additive-modified electrolyte method to alleviate such issues, introducing sodium ferrocyanide (Na
4 Fe(CN)6 ) into aqueous alkaline electrolytes. It could not only capture Zn2+ dissolved on the surface of Na1.86 Zn1.46 [Fe(CN)6 ]0.87 (ZnHCF) electrode material during the cycling process but also conduct redox reactions on the electrode surface to provide additional capacitance. Through experiments and molecular simulation calculations, it showed that Na4 Fe(CN)6 can restrict the movement of Zn dissolution into the electrolyte on the electrode surface. Based on this, an asymmetric supercapacitor based on ZnHCF//activated carbon was assembled with a modified electrolyte. The assembled supercapacitor displayed a specific capacitance of 1,329.65 mF cm-2 , a power density of 2,900 mW cm-2 , and an energy density of 388.28 mW h cm-2 . This study provides a new idea for the design and construction of stable and efficient PBA energy storage materials by inhibiting the leaching of transition metals in PBA., (© 2024 Wiley‐VCH GmbH.)- Published
- 2024
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12. Random amplified DNA polymorphism of Nicotiana tabacum L. cultivars
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C. M. Zheng, C. S. He, H. Y. Zhang, and X. Z. Liu
- Subjects
Genetic diversity ,biology ,Polymorphism (computer science) ,Nicotiana tabacum ,Genotype ,Botany ,UPGMA ,Plant Science ,Cultivar ,Horticulture ,Primer (molecular biology) ,biology.organism_classification ,RAPD - Abstract
The polymorphism, similarities and relationships among Nicotiana tabacum L. cultivars were assessed with RAPD analyses. One hundred and forty-nine bands were detected, of which 94 were polymorphic (63.1 %). A primer distinguishing all of the tested cultivars was found. High similarity between cultivars was revealed, and cultivar relationships were estimated through cluster analysis (UPGMA) based on RAPD data.
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- 2005
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13. The Effect of Harmonic Force Components on Regenerative Stability in End Milling
- Author
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C. M. Zheng, C. Y. Huang, and Junz Jiunn-jyh Wang
- Subjects
Engineering ,Computer simulation ,Stability criterion ,business.industry ,Harmonic ,Force dynamics ,Mechanical engineering ,Helix angle ,Mechanics ,business ,Fourier series ,Stability (probability) ,System dynamics - Abstract
In a systematic manner, this paper investigates the effects of harmonic force components on the regenerative stability of an end milling process. By representing the milling force pulsation in a Fourier series expansion form, the dynamic force components and the average forces due to bi-directional dynamic feed rates are both included in the generalized system dynamics formulation. In the resulting expression for the stability criterion, the spectral features of the milling forces are integrated with the dynamics of the structure, showing the significance or insignificance of the dynamic components of the milling forces in affecting the stability of the milling process. Key system parameters discussed include the magnitude of the average and harmonic forces, the cutter helix angle and the spindle speed. It is shown that a low helix angle and a smaller number of cutting flutes increase the effect of dynamic forces on the system stability. The significance of the harmonic forces is exemplified by the special cutting conditions where the average force becomes zero and the stability limits would be infinite as predicted by models using the average force alone. Improvements in the accuracy of stability lobes resulting from the inclusion of the dynamic forces and the validity of the presented model in general will be illustrated by numerical simulation and verified by experiments as well as by comparison with published results.Copyright © 2003 by ASME
- Published
- 2003
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14. A Frequency Domain Force Model With Shearing and Ploughing Mechanisms for a Generalized Helical End Mill
- Author
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Junz Jiunn-jyh Wang and C. M. Zheng
- Subjects
Engineering ,business.industry ,Shear force ,Mechanics ,Structural engineering ,symbols.namesake ,Die cutting ,Differential geometry ,Fourier analysis ,Frequency domain ,symbols ,End mill ,business ,Shearing (manufacturing) ,Fourier series - Abstract
For a generalized helical end mill, this paper presents a frequency domain force model considering the ploughing as well as the shearing mechanisms. The differential chip load and the corresponding cutting forces are first formulated through differential geometry for a general helical cutting edge. The differential cutting force is assumed to be a linear function of the chip load with a proportional shearing force and a constant ploughing force. The total milling force in the angle domain is subsequently composed through convolution integration and analyzed by Fourier analysis. The frequency domain model has the parameters of a general milling process all integrated in a single framework with their roles clearly defined so that Fourier coefficients of the milling force can be obtained for any analytically definable helical cutter. Applications are illustrated for three common helical cutters: the cylindrical, taper, and ball end mills. Furthermore, as an inverse application, a linear algebraic equation is formulated for the identification of six cutting constants from the average forces of two slot milling tests. Demonstration and verification of the milling force model as well as the identification of cutting constants are carried out through experiments with three types of milling cutters.Copyright © 2002 by ASME
- Published
- 2002
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15. Adsorption thermodynamics and kinetics of nanomaterials: theory and experimental insight into nano-effect.
- Author
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Wang, Mengying, Xue, Yongqiang, and Du, Jianping
- Subjects
NANOSTRUCTURED materials ,METHYLENE blue ,NANOPARTICLES ,ADSORPTION kinetics ,THERMODYNAMICS ,SORBENTS - Abstract
Nanomaterials have excellent adsorption performance due to nano-effect and have been widely used in many fields. The adsorption performance of nanomaterials depends on their adsorption thermodynamics and kinetics. Here, the thermodynamic and kinetic equations of adsorption for spherical nanoparticles are first derived in theory. The mechanisms and regularities of influences of nano-effect on thermodynamics and kinetics, using nano-CdS adsorption of methylene blue as a probe, were investigated. The results show that there are significant influences of nano-effect (i.e., interface area effect and interface tension effect) on the thermodynamics and kinetics of nanoparticle adsorption. When the particle radius is larger and beyond the nanometer scale (∼100 nm), the nano-effect can be neglected. When the radius of the nanoparticle is within 10–50 nm, the nano-effect of adsorption is mainly the interface area effect. When the radius is less than 10 nm, the influences of both the interface area effect and the interface tension effect on adsorption thermodynamics and kinetics become more significant. The theoretic equations and experimental insights in the present work could provide a significant basis and reference for improving and perfecting the adsorption theory involving nanomaterials and provide guidelines for the explanations of adsorption mechanisms as well as the selection of adsorbents. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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16. Design of solvent systems for preparation of ε-CL-20 crystals with high sphericity assisted by molecular simulation.
- Author
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Wang, Hongyu, Liu, Guozhao, Su, Guanwen, Wei, Hongyuan, and Dang, Leping
- Subjects
HYDROGEN bonding interactions ,MOLECULAR dynamics ,CRYSTAL morphology ,TERNARY system ,ELECTROSTATIC interaction - Abstract
In this work, ε-CL-20 crystals with high sphericity, low sensitivity, and high true density were prepared in binary and ternary solvents using solvent–antisolvent recrystallization. The influence mechanisms of temperature, solvent type and solvent composition on crystal morphology were investigated through molecular dynamics simulations with modified attachment energy model. The results reveal that the crystals obtained in the ethyl acetate + chlorobenzene system at 313.15 K have the highest sphericity of 0.8630. The increase in temperature causes the crystals to become sharper. The crystals in ternary solvents retain morphological characteristics of those in the corresponding binary systems and the sphericities are between the two. In ternary systems, hydrogen bonding interactions are affected by the two antisolvents together, and van der Waals and electrostatic interactions can be influenced either by the combined effects of two antisolvents or predominantly by a single antisolvent. It is feasible to adjust interactions by changing growth environments. The temperature, solvent type and solvent composition can affect the diffusion behaviors of solvent molecules and the antisolvent molecules do not affect their mutual diffusion behaviors. This work provides valuable information for the design and optimization of the preparation process of spherical ε-CL-20 crystals. [ABSTRACT FROM AUTHOR]
- Published
- 2025
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17. Therapeutic delivery of oxygen using artificial oxygen carriers demonstrates the possibility of treating a wide range of diseases.
- Author
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Mohanto, Nijaya, Mondal, Himangsu, Park, Young-Joon, and Jee, Jun-Pil
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BLOOD substitutes ,ERYTHROCYTES ,OXYGEN therapy ,STOMACH ulcers ,STEM cells ,OXYGEN carriers - Abstract
Artificial oxygen carriers have emerged as potential substitutes for red blood cells in situations of major blood loss, including accidents, surgical procedures, trauma, childbirth, stomach ulcers, hemorrhagic shock, and blood vessel ruptures which can lead to sudden reduction in blood volume. The therapeutic delivery of oxygen utilizing artificial oxygen carriers as red blood cell substitutes presents a promising avenue for treating a spectrum of disease models. Apart from that, the recent advancement of artificial oxygen carriers intended to supplant conventional blood transfusions draws significant attention due to the exigencies of warfare and the ongoing challenges posed by the COVID-19 pandemic. However, there is a pressing need to formulate stable, non-toxic, and immunologically inert oxygen carriers. Even though numerous challenges are encountered in the development of artificial oxygen carriers, their applicability extends to various medical treatments, encompassing elective and cardiovascular surgeries, hemorrhagic shock, decompression illness, acute stroke, myocardial infarction, sickle cell crisis, and proficient addressing conditions such as cerebral hypoxia. Therefore, this paper provides an overview of therapeutic oxygen delivery using assorted types of artificial oxygen carriers, including hemoglobin-based, perfluorocarbon-based, stem cell-derived, and oxygen micro/nanobubbles, in the treatment of diverse disease models. Additionally, it discusses the potential side effects and limitations associated with these interventions, while incorporating completed and ongoing research and recent clinical developments. Finally, the prospective solutions and general demands of the perfect artificial oxygen carriers were anticipated to be a reference for subsequent research endeavors. [ABSTRACT FROM AUTHOR]
- Published
- 2025
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18. Benchmarking cross-species single-cell RNA-seq data integration methods: towards a cell type tree of life.
- Author
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Zhong, Huawen, Han, Wenkai, Gomez-Cabrero, David, Tegner, Jesper, Gao, Xin, Cui, Guoxin, and Aranda, Manuel
- Published
- 2025
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19. Narrowing and blue-shifting photoluminescence of carbon dots by enhancing sp3-C hybridization using a microreactor.
- Author
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Zhou, Zuxu, Jiang, Kai, Cheng, Zihan, Jiang, Jun, Li, Fengshi, Wu, Yongjian, and Lin, Hengwei
- Abstract
Effectively narrowing and blue-shifting photoluminescence (PL) of carbon dots (CDs) through enhancing their sp
3 -C hybridization degree by using a microreactor are achieved. The resulting CDs emit ultraviolet (UV) PL centered at 345 nm with a full width at half maximum (FWHM) of 54 nm, with blue-shift of over 100 nm and FWHM narrowed by nearly half in comparison with that of the CDs prepared by using the traditional solvothermal method. [ABSTRACT FROM AUTHOR]- Published
- 2025
- Full Text
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20. Zincophilic MOF with N-functional groups for interfacial modification of stable aqueous zinc metal anodes.
- Author
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Sun, Na, Yu, Han, Zhou, Xue, Si, Xiuwen, Wang, Pengfei, Gong, Zhe, Sun, Yaguang, and Zhou, Mingdong
- Abstract
Rechargeable aqueous batteries using zinc as the anode have attracted more and more attention. However, the uncontrolled dendrite growth and hydrogen evolution reaction seriously hinder the performance of zinc anodes. In this work, a two-dimensional (2D) zinc-based MOF (ZHPCA) was synthesized by a simple solvothermal method, which is a Zn(II) coordination polymer with mixed ligands of nitrogen and oxygen donors (H-PCA). Using this MOF as the interface modification layer of the Zn electrode, the ZHPCA@UZn anode was prepared. The N-functional groups in ZHPCA can be used as binding sites for zinc ion deposition and promote their uniform deposition on zinc anodes. The modified layer also effectively inhibited hydrogen evolution and corrosion. It can be observed that the 40 μm ZHPCA@UZn (ZHPCA@UZn) has the longest cycle life exceeding 650 h with a low overpotential of about 46 mV. The zinc ion capacitor assembled by matching the ZHPCA@UZn anode with an activated carbon cathode maintained a specific capacity of 85 mA h g
−1 after 1000 cycles at 1 A g−1 . In conclusion, ZHPCA, the MOF selected in this work, can effectively protect the zinc anode, which provides certain inspiration for the selection of zinc anode coating materials in the future. [ABSTRACT FROM AUTHOR]- Published
- 2025
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21. 复合 DNA 水凝胶在食品中霉菌毒素检测的应用研究进展.
- Author
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张书鸣, 王欣, 王绪武, 杨庆, 王锴, and 王强
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POLYMER networks ,POLYMER structure ,FOOD safety ,HYDROGELS ,NANOPARTICLES - Abstract
Copyright of Food & Fermentation Industries is the property of Food & Fermentation Industries and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2024
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22. New insights into supradense matter from dissecting scaled stellar structure equations.
- Author
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Cai, Bao-Jun and Li, Bao-An
- Subjects
STELLAR structure ,NEUTRON stars ,SPEED of sound ,NUCLEAR models ,DUALITY theory (Mathematics) - Abstract
The strong-field gravity in general relativity (GR) realized in neutron stars (NSs) renders the equation of state (EOS) P (ε) of supradense neutron star matter to be essentially nonlinear and refines the upper bound for ϕ ≡ P / ε to be much smaller than the special relativity (SR) requirement with linear EOSs, where P and ε are respectively the pressure and energy density of the system considered. Specifically, a tight bound ϕ ≲ 0.374 is obtained by perturbatively anatomizing the intrinsic structures of the scaled Tolman–Oppenheimer–Volkoff (TOV) equations without using any input nuclear EOS. New insights gained from this novel analysis provide EOS-model-independent constraints on the properties (e.g., density profiles of the sound speed squared s 2 = d P / d ε and trace anomaly Δ = 1 / 3 − ϕ) of cold supradense matter in NS cores. Using the gravity-matter duality in theories describing NSs, we investigate the impact of gravity on supradense matter EOS in NSs. In particular, we show that the NS mass M NS , radius R , and compactness ξ ≡ M NS / R scale with certain combinations of its central pressure and energy density (encapsulating its central EOS). Thus, observational data on these properties of NSs can straightforwardly constrain NS central EOSs without relying on any specific nuclear EOS model. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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23. Enhancing cancer therapy: advanced nanovehicle delivery systems for oridonin.
- Author
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Su, Yilin, Liu, Lisha, Lin, Chongyang, Deng, Dashi, Li, Yunfei, Huang, Mou, Wang, Yu, Ling, Kangqiu, Wang, Haobing, Chen, Qiyu, and Huang, Guixiao
- Subjects
DRUG delivery systems ,DRUG carriers ,ANTINEOPLASTIC agents ,NANOPARTICLES ,BIOACTIVE compounds - Abstract
Oridonin (ORI), an ent-kaurane diterpenoid derived from Rabdosia rubescens (Hemsl.) H.Hara, serves as the primary bioactive component of this plant. It demonstrates a broad spectrum of therapeutic activities, including moderate to potent anticancer properties, alongside anti-inflammatory, antibacterial, antifibrotic, immunomodulatory, and neuromodulatory effects, thus influencing diverse biological processes. However, its clinical potential is significantly constrained by poor aqueous solubility and limited bioavailability. In alignment with the approach of developing drug candidates from natural compounds, various strategies, such as structural modification and nanocarrier systems, have been employed to address these challenges. This review provides an overview of ORI-based nano-delivery systems, emphasizing their potential to improve the clinical applicability of oridonin in oncology. Although some progress has been made in advancing ORI nano-delivery research, it remains insufficient for clinical implementation, necessitating further investigation. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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24. Biomechanical assessment of anterior plate system, bilateral pedicle screw and transdiscal screw system for high-grade spondylolisthesis: a finite element study.
- Author
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Dhar, Utpal K., Sultan, Hadi, Aghayev, Kamran, Tsai, Chi-Tay, and Vrionis, Frank D.
- Published
- 2024
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25. Prediction of miRNA-disease association based on heterogeneous hypergraph convolution and heterogeneous graph multi-scale convolution.
- Author
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Dai, Wei, Pang, Sifan, He, Zhichen, Fu, Xiaodong, Liu, Li, Liu, Lijun, and Yu, Ning
- Published
- 2024
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26. Nitrous oxide dynamics in the Kara Sea, Arctic Ocean.
- Author
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Muller, Sofia, Fripiat, François, Jaccard, Samuel L., Ponsoni, Leandro, Hölemann, Jens A., Martínez-García, Alfredo, and Delille, Bruno
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SEA ice ,ARCTIC exploration ,NITROGEN cycle ,NITROUS oxide ,CONTINENTAL shelf - Abstract
Previous studies have reported an accumulation of nitrous oxide (N
2 O) on shallow continental shelves of the western Arctic Ocean. In this study, we sampled seawater profiles for N2 O measurements in the eastern Arctic shelves, in the North Kara Sea, in the context of the Arctic Century Expedition. Despite some variability in the vertical distribution, we typically observe an accumulation of N2 O in shelf bottom waters, which correlates with a fixed nitrogen (N) deficit. Longer residence times on the shelf promote greater N2 O enrichment and a larger fixed N deficit. These observations point towards N2 O production at depth, linked to benthic denitrification processes that are intensified on productive shelve areas. However, in surface waters, physical processes – i.e. temperature-dependent solubility and air-sea exchange – emerge as the main factor controlling N2 O concentrations. We observe low saturations of 80% at the surface of open ocean stations influenced by water that has previously flowed beneath sea ice. Arctic surface water becomes undersaturated due to cooling and remains undersaturated due to limited air-sea exchange. River supply does not exert a discernable influence on N2 O concentrations of the studied area. This study reveals the potential of the Arctic Siberian shelves as a sink of atmospheric N2 O during the summer. [ABSTRACT FROM AUTHOR]- Published
- 2024
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27. Cross-scale mechanical softening of Marcellus shale induced by CO2-water--rock interactions using nanoindentation and accurate grain-based modeling.
- Author
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Yiwei Liu, Quansheng Liu, Zhijun Wua, Shimin Liu, Yong Kang, and Xuhai Tang
- Subjects
CARBON dioxide ,NANOINDENTATION ,GEOTECHNICAL engineering ,HYDROGEOLOGISTS ,HYDROGEOLOGY ,UNDERGROUND areas - Abstract
Mechanical softening behaviors of shale in CO
2 -water--rock interaction are critical for shale gas exploitation and CO2 sequestration. This work investigated the cross-scale mechanical softening of shale triggered by CO2 -water--rock interaction. Initially, the mechanical softening of shale following 30 d of exposure to CO2 and water was assessed at the rock-forming mineral scale using nanoindentation. The mechanical alterations of rock-forming minerals, including quartz, muscovite, chlorite, and kaolinite, were analyzed and compared. Subsequently, an accurate grain-based modeling (AGBM) was proposed to upscale the nanoindentation results. Numerical models were generated based on the real microstructure of shale derived from TESCAN integrated minerals analyzer (TIMA) digital images. Mechanical parameters of shale minerals determined by nanoindentation served as input material properties for AGBMs. Finally, numerical simulations of uniaxial compression tests were conducted to investigate the impact of mineral softening on the macroscopic Young's modulus and uniaxial compressive strength (UCS) of shale. The results present direct evidence of shale mineral softening during CO2 -water--rock interaction and explore its influence on the upscale mechanical properties of shale. This paper offers a microscopic perspective for comprehending CO2 -water-shale interactions and contributes to the development of a cross-scale mechanical model for shale. [ABSTRACT FROM AUTHOR]- Published
- 2024
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28. Melatonin Improves H 2 O 2 -Induced Oxidative Stress in Sertoli Cells Through Nrf2-Keap1 Signaling Pathway.
- Author
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Tang, Ying, Wang, Ziming, Chen, Yanru, Wang, Junying, Wang, Hongzhan, Li, Bo, Liu, Bojing, and Zheng, Peng
- Subjects
SERTOLI cells ,WESTERN immunoblotting ,MALE livestock ,HYDROGEN peroxide ,CELLULAR signal transduction - Abstract
Background: Oxidative stress in the testicles of male livestock can cause reduced fertility. Melatonin is a natural product with antioxidant effects, but its specific antioxidant mechanism is still unclear. This study used calf testicular Sertoli cells as materials to explore the mechanism by which melatonin alleviates the oxidative stress of Sertoli cells, laying a foundation for improving the fertility of bulls. Methods: The optimal treatment concentrations of H
2 O2 and melatonin (MLT) were screened out using a CCK8 kit and MDA kit. Then, the cells were divided into four groups for treatment: control group, H2 O2 treatment group, MLT treatment group, and H2 O2 and MLT co-treatment group, then the MDA, ROS, GSH, and SOD contents were detected. Real-time quantitative PCR analysis and Western blot analysis were used to detect genes and proteins related to the Nrf2-Keap1 pathway. Immunofluorescence staining was used to analyze changes in Nrf2. Results: Research results show that the MDA content of cells in the group treated with H2 O2 and MLT combined was significantly lower than that in the group treated with H2 O2 alone, but there was no difference from the control group. Compared with the control group, the ROS level of cells in the H2 O2 -treated group significantly increased, and the content of GSH and SOD significantly decreased. Compared with the H2 O2 -treated group, the ROS level of cells in the H2 O2 and MLT co-treated group significantly decreased, and the content of GSH and SOD increased significantly, but no difference from the control group. Similarly, MTL can alleviate the changes in cellular Nrf2, Keap1, HO-1, and NQO1 expression caused by H2 O2 . Conclusions: Melatonin activates the Nrf2-Keap1 signaling pathway in Sertoli cells, elevating the expression of HO-1 and NQO1, and thereby exerting its antioxidant capabilities. [ABSTRACT FROM AUTHOR]- Published
- 2024
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29. The Impact of Green Market Orientation and Ambidextrous Green Innovation on Organizational Performance: Empirical Study on Small Restaurants in Vietnam.
- Author
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Ngo, Quang‐Huy
- Subjects
SERVICE industries ,MARKET orientation ,BALANCED scorecard ,ORGANIZATIONAL performance ,PERFORMANCE theory - Abstract
The natural resource‐based view (NRBV) posits that aligning business operations toward sustainability fosters innovation and leads to sustainable competitive advantages. Green market orientation (GMO) and green innovation (GI) have emerged as strategic approaches that enhance organizational performance (OP). However, understanding service contexts still needs to be improved, particularly in small restaurants in emerging countries. Additionally, while previous studies on GMO and GI have primarily focused on operationalizing OP based on past performance, there needs to be more understanding of their impact on past performance and future growth. Utilizing a balanced scorecard approach helps to address this limitation effectively. Building on these theoretical frameworks, this study investigates the impact of GMO and ambidextrous GI on OP and the mediating role of ambidextrous GI in the GMO‐OP linkage. Data from 272 small restaurants in Vietnam were collected and analyzed using PLS‐SEM to illuminate the effects of GMO in the restaurant context. The findings support both direct and indirect effects. This study advances NRBV by utilizing balanced scorecard approaches to capture performance outcomes comprehensively. This research also extends GMO studies to the service sector, especially small restaurants, underscoring the pivotal roles of GMO in boosting GI and performance. Lastly, this study follows prior calls for more studies to shed light on the antecedents and consequences of ambidextrous GI. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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30. Therapeutic potential of bark extracts from Macaranga denticulata on renal fibrosis in streptozotocin-induced diabetic rats.
- Author
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Gali, Sreevarsha, Kundu, Amit, Sharma, Swati, Ahn, Mee-Young, Puia, Zothan, Kumar, Vikas, Kim, In Su, Kwak, Jeong Hwan, Palit, Partha, and Kim, Hyung Sik
- Subjects
ADVANCED glycation end-products ,RENAL fibrosis ,DIABETIC nephropathies ,BLOOD sugar ,PATHOLOGICAL physiology - Abstract
Macaranga denticulata (MD) bark is commonly utilized in traditional medicine for diabetes prevention and treatment. The bark extract of MD is rich in prenyl or farnesyl flavonoids and stilbenes, which possess antioxidant properties. Although data suggest the potential therapeutic benefits of the use of MD in treating diabetic nephropathy (DN), the precise mechanisms underlying MD-initiated protective effects against DN are not well understood. This study aimed to assess the renoprotective properties of MD extract by examining renofibrosis inhibition, oxidative stress, and inflammation utilizing streptozotocin-induced DN male Sprague – Dawley rats. Diabetic rats were intraperitoneally injected with streptozotocin (STZ) to induce diabetes. After 6 days, these rats were orally administered MD extract (200 mg/kg/day) or metformin (200 mg/kg/day) for 14 days. The administration of MD extract significantly lowered blood glucose levels, restored body weight, and reduced urine levels of various biomarkers associated with kidney functions. Histopathological analysis revealed protective effects in both kidneys and pancreas. Further, MD extract significantly restored abnormalities in advanced glycation end products, oxidative stress biomarkers, and proinflammatory cytokine levels in STZ-treated rats. MD extract markedly reduced renal fibrosis biomarker levels, indicating recovery from renal injury, and reversed dysregulation of sirtuins and claudin-1 in the kidneys of rats with STZ-induced diabetes. In conclusion, data demonstrated the renoprotective role of MD extract, indicating plant extract's ability to suppress oxidative stress and regulate proinflammatory pathways during pathological changes in diabetic nephropathy. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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31. Episodic Seafloor Hydrothermal Alteration as a Source of Stable Remagnetizations in Archean Volcanic Rocks.
- Author
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Brenner, A. R., Fu, R. R., Brown, A. J., Hodgin, E. B., Flannery, D. T., and Schmitz, Mark D.
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GEOLOGICAL time scales ,GEOMAGNETISM ,HYDROTHERMAL alteration ,RECRYSTALLIZATION (Geology) ,REMANENCE ,MAGNETITE - Abstract
Interpreting the paleomagnetic records of altered rocks, especially those from Earth's earliest history, is complicated by metamorphic overprints and recrystallization of ferromagnetic minerals. However, these records may be as valuable as a primary signal if the timing and mechanism of alteration‐related remagnetizations can be ascertained. We illustrate the success of this approach in the case of seafloor hydrothermal alteration by integrating simple rock magnetic and magnetic microscopy data with petrography, hyperspectral imagery, aeromagnetic surveys, field mapping, and geochronology of Paleoarchean basalts from North Pole Dome located in the East Pilbara Craton, Western Australia. We identify 12 hydrothermal episodes during the deposition of the stratigraphy between ∼3490 and 3350 Ma. These episodes produced stratabound zones of hydrothermal alteration with predictable facies successions of mineral assemblages reflecting sub‐seafloor gradients in fluid temperature, pH, composition, and water/rock ratios. Rock magnetic data and magnetic microscopy pinpoint the secondary ferromagnetic minerals within each alteration assemblage, revealing a specific single‐domain magnetite population within leucoxenes (titanite and anatase after primary titanomagnetites) that always accompanies low‐water/rock alteration in fluids buffered to pH equilibrium with the host basalts. Highly uniform magnetic properties indicate that once formed, these magnetites remain unchanged upon further exposure to rock buffered fluids, stabilizing them against later alteration events and making them durable paleofield recorders. The altered basalts hosting this magnetite have unique and consistent appearances, mineralogy, IR absorption features, aeromagnetic signatures, and magnetic properties across all hydrothermal systems studied here, highlighting how integrating these data sets can identify and interpret this alteration style in future paleomagnetic investigations. Plain Language Summary: Paleomagnetists interpret the magnetic signals preserved in rocks to understand plate tectonics and the Earth's magnetic field in the deep past. However, rocks can get altered via heat, pressure, or chemical reactions, which also alter these magnetic signals. The aim of this study is to demonstrate that one type of alteration—chemical alteration of rocks as they marinate in circulating hot water within seafloor hydrothermal systems—modifies the magnetic signals of rocks in order to use them for future paleomagnetic studies. Using airborne infrared imaging, magnetic field mapping, field observations, and radiometric dating, we demonstrate that an area of Western Australia called North Pole Dome experienced a dozen seafloor hydrothermal alteration events over 3 billion years ago. We then use magnetic measurements and mineralogical observations to document how these hydrothermal systems altered the magnetic signals in their host rocks. These analyses reveal a recognizable population of altered rocks that can preserve paleomagnetic signals related to hydrothermal alteration. This is because the alteration results in the growth of very fine‐grained magnetite with all the necessary characteristics to reliably and durably hold onto magnetic signals over geologic time. Key Points: Field mapping, remote sensing, and petrographic data identify 12 seafloor hydrothermal episodes in an Archean volcanic successionMagnetic and mineralogical characteristics of the basalts predictably co‐vary with alteration facies across all hydrothermal systemsWe establish a geologic, chronological, and petrographic framework for identifying seafloor hydrothermal remagnetization in basalts [ABSTRACT FROM AUTHOR]
- Published
- 2024
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32. Mechanisms and control measures of low temperature storage-induced chilling injury to solanaceous vegetables and fruits.
- Author
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Yuan, Qi, Jiang, Yaqin, Yang, Qihong, Li, Weiliu, Gan, Guiyun, Cai, Liangyu, Li, Wenjia, Qin, Chunchun, Yu, Chuying, and Wang, Yikui
- Subjects
TEMPERATURE control ,LOW temperatures ,PHYSIOLOGY ,VEGETABLE storage ,POSTHARVEST diseases - Abstract
Low temperature storage is widely used for storage and transportation of fruits and vegetables after harvest. As a cold-sensitive fruit vegetable, post-harvest solanaceous vegetables and fruits are susceptible to chilling injury during low temperature storage, which reduces its sensory quality and edible quality and shortens its storage period, thus leading to huge economic losses. Therefore, it is an essential to clarify the occurrence mechanism of chilling injury caused by low temperature storage in solanaceous vegetables and fruits, and to propose corresponding prevention and control measures for chilling injury. In recent years, a series of progress has been made in the research on chilling injury prevention and control and low temperature stress tolerance of solanaceous vegetables and fruits. This paper describes the chilling injury symptoms of postharvest solanaceous vegetables and fruits, clarifies the physiological and biochemical mechanisms in the chilling injury process, the molecular mechanisms, and prevention and control measures, and summarizes the latest research advancements on chilling injury and chilling tolerance regulation of solanaceous vegetables and fruits, which can provide valuable references for low temperature storage and chilling injury prevention and control measures of solanaceous vegetables and fruits. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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33. Vulnerability of Arctic-Boreal methane emissions to climate change.
- Author
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Parmentier, Frans-Jan W., Thornton, Brett F., Silyakova, Anna, and Christensen, Torben R.
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CLIMATE feedbacks ,METHANE hydrates ,ATMOSPHERIC methane ,GAS hydrates ,LANDFORMS - Abstract
The rapid warming of the Arctic-Boreal region has led to the concern that large amounts of methane may be released to the atmosphere from its carbon-rich soils, as well as subsea permafrost, amplifying climate change. In this review, we assess the various sources and sinks of methane from northern high latitudes, in particular those that may be enhanced by permafrost thaw. The largest terrestrial sources of the Arctic-Boreal region are its numerous wetlands, lakes, rivers and streams. However, fires, geological seeps and glacial margins can be locally strong emitters. In addition, dry upland soils are an important sink of atmospheric methane. We estimate that the net emission of all these landforms and point sources may be as much as 48.7 [13.3–86.9] Tg CH
4 yr−1 . The Arctic Ocean is also a net source of methane to the atmosphere, in particular its shallow shelves, but we assess that the marine environment emits a fraction of what is released from the terrestrial domain: 4.9 [0.4–19.4] Tg CH4 yr−1 . While it appears unlikely that emissions from the ocean surface to the atmosphere are increasing, now or in the foreseeable future, evidence points towards a modest increase from terrestrial sources over the past decades, in particular wetlands and possibly lakes. The influence of permafrost thaw on future methane emissions may be strongest through associated changes in the hydrology of the landscape rather than the availability of previously frozen carbon. Although high latitude methane sources are not yet acting as a strong climate feedback, they might play an increasingly important role in the net greenhouse gas balance of the Arctic-Boreal region with continued climate change. [ABSTRACT FROM AUTHOR]- Published
- 2024
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34. Visible light-promoted C3–H alkoxycarbonylation of quinoxalin-2(1H)-ones or coumarins with alkyloxalyl chlorides.
- Author
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Lin, Yanchun, Zhou, Xi, Zheng, Yixuan, Chen, Bingran, Liu, Yang, Zhang, Yi, Yan, Qiongjiao, Wang, Wei, and Chen, Fener
- Published
- 2024
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35. Quantification of streamflow response to climate change and human activities within upstream mountainous areas of the Daqing River Basin, Northern China.
- Author
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Li, Zengyi, Chen, Weifan, and Wang, Linna
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WATER conservation projects ,WATER management ,GLOBAL warming ,HYDROLOGICAL stations ,ELASTICITY (Economics) - Abstract
The Daqinghe River Basin is located in the North China Plain. In recent years, however, climate warming, drying, and intense human activities have led to declining ecosystem functions and shrinking wetlands in the region. Understanding streamflow changes in the upstream mountainous areas of the Daqinghe River Basin in this changing environment and identifying the driving factors can provide a scientific basis for water resources management and optimization in these areas. This study focuses on the Beihedian River watershed, the Xidayang Reservoir watershed, and the Wangkuai Reservoir watershed in the upstream mountainous areas of the Daqinghe River. It is based on hydro-meteorological data collected between 1963 and 2019. The methods used in the study include the linear tendency estimation method, the non-parametric Mann-Kendall trend test, the elasticity coefficient method, and hydrological simulation methods. The results of this study suggest that the streamflow, precipitation, and potential evapotranspiration (PET) in the three watersheds showed an overall decreasing trend. The minimum precipitation decrease rate ranged from −1.09 to −0.55 mm/a, and the minimum streamflow decreasing rate at the Beihedian Hydrological Station was −1.32 mm/a, with a minimum range of 0–176.03 mm. Change-point analysis revealed that the streamflow in the Beihedian River and Xidayang Reservoir watersheds experienced a significant change point around 1999, with a significant level of α=0.05. As for the Wangkuai Reservoir watershed, a significant change point was observed around 1980, which is likely attributable to land system reforms and protective forest projects. The attribution analysis which combined both climate change and human activities using the elasticity coefficient method and hydrological simulation methods indicated that climate change contributed an average of 32.93%, 34.50%, and 35.12% to the reduction in streamflow in the three watersheds, respectively. Human activities accounted for an average contribution of 67.07%, 65.50%, and 64.88%, respectively. Water conservancy projects, afforestation, and other human activities were identified as the primary factors contributing to streamflow decreases. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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- View/download PDF
36. Complement System and Adhesion Molecule Skirmishes in Fabry Disease: Insights into Pathogenesis and Disease Mechanisms.
- Author
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Magnusen, Albert Frank and Pandey, Manoj Kumar
- Subjects
CD54 antigen ,ANGIOKERATOMA corporis diffusum ,PATHOLOGY ,VASCULAR endothelial cells ,COMPLEMENT receptors ,CELL adhesion ,X chromosome - Abstract
Fabry disease is a rare X-linked lysosomal storage disorder caused by mutations in the galactosidase alpha (GLA) gene, resulting in the accumulation of globotriaosylceramide (Gb3) and its deacetylated form, globotriaosylsphingosine (Lyso-Gb3) in various tissues and fluids throughout the body. This pathological accumulation triggers a cascade of processes involving immune dysregulation and complement system activation. Elevated levels of complement 3a (C3a), C5a, and their precursor C3 are observed in the plasma, serum, and tissues of patients with Fabry disease, correlating with significant endothelial cell abnormalities and vascular dysfunction. This review elucidates how the complement system, particularly through the activation of C3a and C5a, exacerbates disease pathology. The activation of these pathways leads to the upregulation of adhesion molecules, including vascular cell adhesion molecule 1 (VCAM1), intercellular adhesion molecule 1 (ICAM1), platelet and endothelial cell adhesion molecule 1 (PECAM1), and complement receptor 3 (CR3) on leukocytes and endothelial cells. This upregulation promotes the excessive recruitment of leukocytes, which in turn exacerbates disease pathology. Targeting complement components C3a, C5a, or their respective receptors, C3aR (C3a receptor) and C5aR1 (C5a receptor 1), could potentially reduce inflammation, mitigate tissue damage, and improve clinical outcomes for individuals with Fabry disease. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
37. Characteristics of ocular-related emergency department visits: Five-years data from a tertiary care center in Riyadh, Saudi Arabia.
- Author
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Alshammari, Abdulmohsen, Alqadhy, Naif, Gharawi, Abdulaziz, Alqahtani, Bader, Alagha, Saif, AlShenaiber, Mohammed, Almalik, Fahad, and Alshibani, Abdullah
- Subjects
EMERGENCY room visits ,OPHTHALMOLOGIC emergencies ,NOSOLOGY ,RETINAL detachment ,AGE groups ,OLDER patients - Abstract
Background: Ocular emergencies (OE) include ocular trauma, infections, retinal detachment, and uveitis. Due to the limited number of studies describing ocular emergencies requiring Emergency Department (ED) visits in Saudi Arabia, there is a need for further studies addressing this topic. Therefore, this study aimed to assess and describe the incidence, clinical presentation, and causes of ocular-related ED visits at a tertiary hospital in Riyadh, Saudi Arabia. Methods: This was a retrospective cohort study. Medical records were reviewed for all patients (all age groups) patients presenting at the ED from 1 January 2019 to 31 October 2023 where data for patients with any ocular emergency was extracted using an Excel sheet. Data analysis was performed using RStudio (R version 4.3.1). Baseline information was described using frequencies and proportions. Types of Ocular emergencies were described using the International Classification of Diseases, 10th Revision (ICD-10) codes and presented using frequencies and proportions. The distribution of ocular emergencies across months and age groups was expressed using chart figures. Results: A total of 15,321 ocular-related ED visits were included in this study. Almost 51% of patients were males. The mean age at diagnosis was 25.5 ± 22.1 years. More than half of the patients (51.0%) were diagnosed during childhood (<18 years), while proportions of older ages declined gradually. Average presentations of ocular emergencies in a single month ranged from 200 to 400. Conjunctival disorders including conjunctivitis (29.8%) were the most frequent ocular emergencies. Conclusion: The findings of this study showed that ocular emergencies are more prevalent in younger patients (aged <18 years), more commonly due to conjunctivitis. This highlights the need for policymakers to assess the causes of such emergency in this population and implement prevention strategies. Moreover, an average of 200 to 400 emergency visits per month are ocular-related. This finding could help policymakers understand the burden of ocular emergencies on the ED and the pressure that could add to the ED staff to provide appropriate care for these patients. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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- View/download PDF
38. Nitrogen-doped carbon coated zinc selenide nanoparticles derived from metal–organic frameworks as high-rate and long-life anode materials for half/full sodium-ion batteries.
- Author
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Wang, Yunxiu, Wang, Yilin, Cai, Zenghui, Yu, Zhijiang, Dong, Hao, Zhang, Yifan, Zhou, Yanli, Zhang, Xintao, Zhai, Yanjun, Jiang, Fuyi, and Dong, Caifu
- Published
- 2024
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39. 荔枝裂果研究综述与展望.
- Author
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李茜玟, 孙浩爽, 庞学群, and 张昭其
- Subjects
MOLECULAR biology ,FRUIT quality ,LITCHI ,SUSTAINABLE development ,SAPINDACEAE - Abstract
Copyright of Guangdong Agricultural Sciences is the property of South China Agricultural University, Guangdong Academy of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2024
- Full Text
- View/download PDF
40. 土壤环境承载力研究进展及展望.
- Author
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陈睿涵, 王霞, and 仓龙
- Subjects
ENVIRONMENTAL research ,ENVIRONMENTAL quality ,EVALUATION methodology ,CONCEPTUAL history ,SYSTEM dynamics - Abstract
Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2024
- Full Text
- View/download PDF
41. Overcoming Barriers to Healthcare Reform: A Call to Action.
- Author
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Ainslie, Marcy, Collins, Alicia F., Hebert, Danielle, Moore, Jeanne, Schriefer, Susan P., and Venzke, Margaret Hadro
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POLICY sciences ,CORPORATE culture ,PSYCHOLOGICAL resilience ,EMPLOYEE retention ,HEALTH services accessibility ,INTERPROFESSIONAL relations ,HEALTH insurance reimbursement ,HEALTH policy ,WORK environment ,EVALUATION of medical care ,DECISION making ,NURSING education ,HEALTH care reform ,PATIENT-centered care ,LABOR demand ,NURSING practice ,SOCIAL support ,PRACTICAL politics ,MEDICAL practice ,HEALTH care teams - Abstract
The success of healthcare reform hinges on policymaker, regulator, and administrator actions that shape policies at various levels. These policies can either facilitate or hinder the practice of healthcare professionals and collaborative work environments. It is imperative for all healthcare professionals to fully utilize their education and certification, as fostering an equitable workplace culture is vital for retaining staff and improving access to care. Using nurse practitioners (NPs) as an exemplar, this article aims to specify systemic barriers to healthcare reform and call for policymakers, regulators, and clinical agency administrators to enact change. Barriers to NP practice include restrictive oversight by external stakeholders, financial incentives for indirect billing, and hierarchical constraints that limit NP contributions to the healthcare system. The growing healthcare provider shortage disproportionately impacts primary care and rural settings. NPs are increasingly more likely to fill these roles than medical doctors and have documented positive patient health outcomes. Removing systemic obstacles for NP practice increases access to care. Nursing—the largest healthcare workforce with diverse roles—operates under complex oversight from multiple organizations for licensure, accreditation, certification, and education. The recent trend of external stakeholders influencing and requiring additional oversight has created barriers to nursing practice. Despite national education, accreditation, and certification standards, nursing licensure and practice are increasingly negotiated with external stakeholders and supervised at the state and institutional levels. Supporting all healthcare professionals to practice according to their education and certification can advance healthcare reform, address workforce shortages, increase access to care, and improve health. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
42. Confining Ionic Liquids in Developing Quasi-Solid-State Electrolytes for Lithium Metal Batteries.
- Author
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Hu H, Li J, and Ji X
- Abstract
The concept of confining ionic liquids (ILs) in developing quasi-solid-state electrolytes (QSSEs) has been proposed, where ILs are dispersed in polymer networks/backbones and/or filler/host pores, forming the so-called confinement, and great research progress and promising research results have been achieved. In this review, the progress and achievement in developing QSSEs using IL-confinement for lithium metal batteries (LMBs), together with advanced characterizations and simulations, were surveyed, summarized, and analyzed, where the influence of specific parameters, such as IL (type, content, etc.), substrate (type, structure, surface properties, etc.), confinement methods, and so on, was discussed. The confinement concept was further compared with the conventional one in other research areas. It indicates that the IL-confinement in QSSEs improves the performance of electrolytes, for example, increasing the ionic conductivity, widening the electrochemical window, and enhancing the cycle performance of the assembled cells, and being different from those in other areas, that is, the IL-confinement concept in the battery area is in a broad extent. Finally, insights into developing QSSEs in LMBs with the confinement strategy were provided to promote the development and application of QSSE LMBs., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)
- Published
- 2024
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43. Evaluation of groundwater remediation strategies at petroleum contaminated sites based on groundwater modelling approach.
- Author
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L H Yang, L X Jing, and C M Zheng
- Published
- 2019
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44. Preparation and evaluation of Fe3O4@C@NiCo-LDH@CDs composites for magnetic solid-phase extraction of trace endocrine disruptors.
- Author
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Qin, Honglin, Xu, Ruozhu, Qiao, Lizhen, Zhai, Xupeng, Guo, Peixin, Li, Chen, and Han, Bingyan
- Published
- 2024
- Full Text
- View/download PDF
45. A population of Vasa2 and Piwi1 expressing cells generates germ cells and neurons in a sea anemone.
- Author
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Miramón-Puértolas, Paula, Pascual-Carreras, Eudald, and Steinmetz, Patrick R. H.
- Subjects
BIOLOGICAL evolution ,SEA anemones ,GERM cells ,SOMATIC cells ,PROGENITOR cells - Abstract
Germline segregation, essential for protecting germ cells against mutations, occurs during early embryogenesis in vertebrates, insects and nematodes. Highly regenerative animals (e.g., cnidarians), however, retain stem cells with both germinal and somatic potentials throughout adulthood, but their biology and evolution remain poorly understood. Among cnidarians (e.g., sea anemones, jellyfish), stem cells are only known in few hydrozoans (e.g., Hydra). Here, we identify and characterize a rare, multipotent population of stem and/or progenitor cells expressing the conserved germline and multipotency proteins Vasa2 and Piwi1 in the sea anemone Nematostella vectensis. Using piwi1 and vasa2 transgenic reporter lines, we reveal that the Vasa2+/Piwi1+ cell population generates not only gametes, but also a diversity of proliferative somatic cells, including neural progenitors, in juveniles and adults. Our work has uncovered a multipotent population of Vasa2+/Piwi1+ stem/progenitor cells that forms the cellular basis to understand body plasticity and regenerative capacities in sea anemones and corals. Stem or progenitor cells have so far remained elusive in sea anemones or corals. Here, the authors show that a population of cells that express Vasa2 and Piwi1 genes can generate both germ and somatic cells, for example neurons, in a sea anemone. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
46. Oxygen vacancy enhanced catalytic oxidation of H2S based on ZnO-incorporated N-doped hollow carbon nanofibers for cathode construction for high-performance Li–S batteries.
- Author
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Sun, Minghui, Wang, Xuzhen, Ji, Xingliang, Qin, Lei, Zhao, Zongbin, and Qiu, Jieshan
- Abstract
As one of the most toxic pollutants, hydrogen sulfide (H
2 S) is hazardous to human health and the environment. Selective oxidation of H2 S to elemental sulfur (S) over carbon-based catalysts has emerged as an interesting solution owing to the advantages of low reaction temperature (20–30 °C), high desulfurization efficiency and accuracy. Interestingly, the produced carbon–sulfur composites could be directly used as cathodes for high-performance lithium–sulfur batteries (LSBs). Herein, a carbon-based catalyst consisting of nitrogen-doped hollow carbon nanofiber (NHCF) loading oxygen-deficient ZnO (Od -ZnO/NHCFs) is fabricated to achieve this integrated application. The oxygen vacancy in Od -ZnO/NHCFs is able to enhance the chemisorption of H2 S and generates a ZnO/ZnS heterostructure; besides, it can enrich O2 ˙− radicals through electrostatic interaction to improve the catalytic oxidation of adsorbed H2 S to elemental sulfur. Meanwhile, the hollow framework of NHCFs enables rapid gas diffusion and adequate storage space for solid sulfur; thus, the in situ construction of a high S-loading cathode (S@Od -ZnO/ZnS/NHCFs) for LSBs is realized during the desulfurization process. More importantly, the formed ZnO/ZnS heterostructure can boost the electrochemical kinetic behavior in the discharge/charge processes of LSBs. Coupled with the physical confinement of hollow structures on polysulfides, the as-prepared S@Od -ZnO/ZnS/NHCF cathode exhibits outstanding electrochemical performance in LSBs. This work opens up a new avenue for the synergistic application of high-performance LIB electrodes for the control and conversion of sulfur-containing pollutants. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
47. 以国家任务带学科 抢占地理资源科技制高点 把科研成果铭刻在祖国大地上
- Author
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孙福宝, 王生林, and 姜鲁光
- Abstract
Copyright of Bulletin of the Chinese Academy of Sciences / Chung-kuo ko Hsueh Yuan Yuan Kan is the property of Institutes of Science & Development, Chinese Academy of Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2024
- Full Text
- View/download PDF
48. Geothermal Energy Extraction–Induced Ground Movement Monitoring by InSAR and Its Implication for Reservoir Management.
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Wang, Zhaoxi, Lv, Boshun, Li, Jonathan, and Yin, Shunde
- Subjects
GEOTHERMAL resources ,GROUNDWATER recharge ,SYNTHETIC aperture radar ,POWER resources ,DEFORMATION of surfaces ,LAND subsidence - Abstract
Global climate change highlights the significance of renewable clean energy. Geothermal energy from oilfields is abundant and can be utilized for residential heating and oil transportation. However, unreasonable heat exchange methods lead to groundwater level decline. Differences and delays between water extraction and reinjection inevitably cause land subsidence, hindering the sustainable utilization of geothermal energy resources. It is crucial to effectively monitor large-scale ground surface deformation characteristics in geothermal fields. In the research, 55 Sentinel-1A images from October 2018 to May 2022 were collected, and the ground deformation of Caofeidian new district in Bohai Bay Basin, where Nanpu Oilfield is located, in North China, was inverted by short baseline subsets-interferometric synthetic aperture radar (SBAS-InSAR) technology. The maximum subsidence velocity in Caofeidian new district exceeded 50 mm/year. Since April 2019, there has been concentrated ground subsidence in the Caofeidian new district, with a maximum cumulative subsidence exceeding 50 mm. The maximum cumulative subsidence exceeded 150 mm by May 2022. Combined with pumping and recharging tests near heating project in Caofeidian new district, the temporal subsidence mechanisms were revealed. The water extraction from the thermal reservoir caused drainage consolidation of the strata, triggering rapid subsidence in November. In April, discrepancy between water extraction and reinjection flow rate in thermal reservoir caused drainage consolidation of the strata, further exacerbating the subsidence trend. During rainy seasons, despite water reinjection and groundwater replenishment from precipitation, the strata in the Caofeidian new district underwent irreversible plastic deformation, with a slow rebound process, lagging behind urban areas without geothermal development by one month. InSAR is a reliable technology for understanding the ground deformation process in geothermal fields. Clarifying the subsidence mechanisms guides the selection of water-heat exchange methods, ensuring the sustainable development of geothermal resources. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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49. Integrating nurse practitioners into primary healthcare to advance health equity through a social justice lens: An integrative review.
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Adams, Sue, Komene, Ebony, Wensley, Cynthia, Davis, Josephine, and Carryer, Jenny
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NURSES ,PUBLIC health infrastructure ,HEALTH self-care ,OCCUPATIONAL roles ,SOCIAL justice ,AUTONOMY (Psychology) ,ENDOWMENTS ,RESEARCH funding ,PRIMARY health care ,CINAHL database ,LEADERSHIP ,MEDLINE ,THEMATIC analysis ,CONCEPTUAL structures ,HEALTH equity ,ONLINE information services ,QUALITY assurance ,SOCIAL support ,COGNITION - Abstract
Aim: To develop a framework to guide the successful integration of nurse practitioners (NPs) into practice settings and, working from a social justice lens, deliver comprehensive primary healthcare which advances health equity. Design: Integrative review. Methods: The integrative review was informed by the Whittemore and Knafl's framework and followed the Preferred Reporting for Systematic Reviews and Meta‐Analyses guidelines. Quality was assessed using the Johns Hopkins Research Evidence Appraisal Tool. Findings were extracted and thematically analysed using NVivo. A social justice lens informed all phases. Data Sources: Databases, including CINAHL, PubMed, Scopus and Web of Science, were searched for peer‐reviewed literature published in English between 2005 and April 2022. Results: Twenty‐eight articles were included. Six themes were identified at the individual (micro), local health provider (meso), and national systems and structures (macro) levels of the health sector: (1) autonomy and agency; (2) awareness and visibility; (3) shared vision; (4) leadership; (5) funding and infrastructure; and (6) intentional support and self‐care. The evidence‐based framework is explicitly focused on the components required to successfully integrate NPs into primary healthcare to advance health equity. Conclusion: Integrating NPs into primary healthcare is complex and requires a multilevel approach at macro, meso and micro levels. NPs offer the potential to transform primary healthcare delivery to meet the health needs of local communities. Health workforce and integration policies and strategies are essential if the contribution of NPs is to be realized. The proposed framework offers an opportunity for further research to inform NP integration. Impact Statement: Nurse practitioners (NPs) offer the potential to transform primary healthcare services to meet local community health needs and advance health equity.Globally, there is a lack of guidance and health policy to support the integration of the NP workforce.The developed framework provides guidance to successfully integrate NPs to deliver comprehensive primary healthcare grounded in social justice.Integrating NPs into PHC is complex and requires a multilevel approach at macro, meso and micro levels.The framework offers an opportunity for further research to inform NP integration, education and policy. Summary Statement: What problem did the study address: The challenges of integrating nurse practitioners (NPs) into primary healthcare (PHC) are internationally recognized. Attempts to establish NP roles in New Zealand have been ad hoc with limited research, evidence‐informed frameworks or policy to guide integration initiatives. Our review builds on existing international literature to understand how NPs are successfully integrated into PHC to advance health equity and provide a guiding framework.What were the main findings: Six themes were identified across individual (micro), local health provider (meso) and national systems and structures (macro) levels as fundamental to NP integration: autonomy and agency; awareness and visibility of the NP and their role; a shared vision for the direction of primary healthcare utilizing NP scope of practice; leadership in all spaces; necessary funding and infrastructure; and intentional support and self‐care.Where and on whom will the research have an impact: Given extant health workforce challenges together with persisting health inequities, NPs provide a solution to delivering comprehensive primary healthcare from a social justice lens to promote healthcare access and health equity. The proposed evidence‐informed framework provides guidance for successful integration across the health sector, training providers, as well as the NP profession, and is a platform for future research. Reporting Method: This integrative review adhered to the Preferred Reporting for Systematic Reviews and Meta‐Analyses (PRISMA) method. Patient or Public Contribution: No patient or public contribution. [ABSTRACT FROM AUTHOR]
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- 2024
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50. Enhancing Antimicrobial Peptide Activity through Modifications of Charge, Hydrophobicity, and Structure.
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Gagat, Przemysław, Ostrówka, Michał, Duda-Madej, Anna, and Mackiewicz, Paweł
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ANTIMICROBIAL peptides ,PEPTIDOMIMETICS ,PEPTIDES ,BACTERIAL cell walls ,AMINO acids - Abstract
Antimicrobial peptides (AMPs) are emerging as a promising alternative to traditional antibiotics due to their ability to disturb bacterial membranes and/or their intracellular processes, offering a potential solution to the growing problem of antimicrobial resistance. AMP effectiveness is governed by factors such as net charge, hydrophobicity, and the ability to form amphipathic secondary structures. When properly balanced, these characteristics enable AMPs to selectively target bacterial membranes while sparing eukaryotic cells. This review focuses on the roles of positive charge, hydrophobicity, and structure in influencing AMP activity and toxicity, and explores strategies to optimize them for enhanced therapeutic potential. We highlight the delicate balance between these properties and how various modifications, including amino acid substitutions, peptide tagging, or lipid conjugation, can either enhance or impair AMP performance. Notably, an increase in these parameters does not always yield the best results; sometimes, a slight reduction in charge, hydrophobicity, or structural stability improves the overall AMP therapeutic potential. Understanding these complex interactions is key to developing AMPs with greater antimicrobial activity and reduced toxicity, making them viable candidates in the fight against antibiotic-resistant bacteria. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
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