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Evaluation of the Pharmacological Potential of Strychnos camptoneura Trunk Bark Hydroethanol Extract on Reproductive Functions in Male Guinea Pigs (Cavia porcellus) Exposed to Cypermethrin
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作者 Akassa Herman Moukouma Constantin +5 位作者 Diakouka Diambalou Rancia Colombe Njilo Tchatchouang Didier Gestil Mouzita Judicaël Ferry Mpika M’boko Etou Ossibi Arnaud Wilfrid Abena Ange Antoine 《American Journal of Plant Sciences》 CAS 2024年第10期884-898,共15页
The main objective of this study was to evaluate the pharmacological potential of the hydroethanol extract of Strychnos camptoneura trunk bark on reproductive functions in male guinea pigs exposed to cypermethrin. The... The main objective of this study was to evaluate the pharmacological potential of the hydroethanol extract of Strychnos camptoneura trunk bark on reproductive functions in male guinea pigs exposed to cypermethrin. The results showed that administration of the hydroethanolic extract (100 and 250 mg/kg) of Strychnos camptoneura trunk bark after exposure of the animals to cypermethrin induced a highly significant (p Strychnos camptoneura trunk bark produced a highly significant (p Strychnos camptoneura trunk bark may have protective effects against cypermethrin-induced male infertility due to its androgenic, spermatogenic and antiradical properties. 展开更多
关键词 Strychnos Camptoneura Guinea Pig Males CYPERMETHRIN Reproductive Function
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The biological functions and metabolic pathways of valine in swine
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作者 Chuni Wang Yao Peng +4 位作者 Yiru Zhang Juan Xu Sheng Jiang Leli Wang Yulong Yin 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期20-34,共15页
Valine is an essential amino acid and a type of branched-chain amino acid. Due to the involvement of branchedchain amino acids in various metabolic pathways, there has been a surge of interests in valine nutrition and... Valine is an essential amino acid and a type of branched-chain amino acid. Due to the involvement of branchedchain amino acids in various metabolic pathways, there has been a surge of interests in valine nutrition and its role in animal physiology. In pigs, the interactions between valine and other branched-chain amino acids or aromatic amino acids are complex. In this review, we delve into the interaction mechanism, metabolic pathways, and biological functions of valine. Appropriate valine supplementation not only enhances growth and reproductive performances, but also modulates gut microbiota and immune functions. Based on past observations and interpretations, we provide recommended feed levels of valine for weaned piglets, growing pigs, gilts, lactating sows, barrows and entire males. The summarized valine nutrient requirements for pigs at different stages offer valuable insights for future research and practical applications in animal husbandry. 展开更多
关键词 Additional dosage Biological function Metabolic pathway PIG VALINE
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THE(p,q)-ANALOG OF MULTIVALENT BAZILEVIC FUNCTIONS ASSOCIATED WITH A LIMACON
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作者 HUANG An LONG Pin-hong +1 位作者 LIU Jin-lin Gangadharan Murugusundaramoorthy 《数学杂志》 2024年第6期471-484,共14页
This paper studies the problem of functional inequalities for analytic functions in classical geometric function theory.Using the di erential subordination principle and(p,q)-derivative operator,it introduces(p,q)-ana... This paper studies the problem of functional inequalities for analytic functions in classical geometric function theory.Using the di erential subordination principle and(p,q)-derivative operator,it introduces(p,q)-analog of a class of multivalently Bazilevic functions as-sociated with a limacon function,and obtains the corresponding coefficient estimates and the Fekete-Szego inequality,which extend and improve the related results for starlike functions,even q-starlike functions. 展开更多
关键词 Fekete-Szego inequality symmetric Toeplitz determinant multivalent function Bazilevic function (p q)-derivative operator
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Crustal structure in the Anyuan Coal Mine and its adjacent areas of Jiangxi Province by P-wave receiver functions
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作者 Xingmian Zhang Meng Gong +5 位作者 Jian Lü Hongxing Li Jie Hu Junwen He Jianhua Peng Bingyue Liu 《Earthquake Research Advances》 CSCD 2024年第1期47-58,共12页
We collected high-quality teleseismic events recorded by 12 broadband seismographs deployed in the Anyuan Coal Mine and its adjacent areas in Pingxiang City,Jiangxi Province for nearly two years.The H-κ-c stacking me... We collected high-quality teleseismic events recorded by 12 broadband seismographs deployed in the Anyuan Coal Mine and its adjacent areas in Pingxiang City,Jiangxi Province for nearly two years.The H-κ-c stacking method was employed to obtain the crustal thickness and Poisson's ratio distribution,then the characteristics of crustal structure below the stations were obtained by using the time-domain linear inversion method.The crustal thickness in the Anyuan Coal Mine and its adjacent areas ranges from approximately 32~35 km,with an average thickness of 33 km,which is consistent with the crustal thickness results in South China from previous studies using the receiver function method.The average Poisson's ratio of the crustal bulk composition in the study area varies between 0.22 and 0.25,which is lower than the global value with a 0.27 average,indicating a predominantly intermediate-acidic or felsic crustal composition.There is a weak negative correlation between Poisson's ratio and crustal thickness estimates in the Anyuan Coal Mine and its adjacent areas,suggesting that the absence of mafic-ultramafic materials in the lower crust is associated with the process of crustal delamination.The velocity inversion results indicate that the crustal structure including three velocity discontinuity interfaces,with the first at a depth of approximately 1.5 km,the second at about 10~15 km,and the third being the Moho.The study also indicates that the results obtained by the H-κ-c stacking method are significantly better than those obtained by the H-κmethod,effectively reducing the standard deviation and dispersion of crustal thickness and vP/vSratio. 展开更多
关键词 Anyuan Coal Mine Receiver function H-κ-c stacking Crustal thickness Poisson's ratio
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Crustal and uppermost mantle structure of the northeastern Qinghai-Xizang Plateau from joint inversion of surface wave dispersions and receiver functions with P velocity constraints
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作者 Pei Zhang Xiaodong Song +2 位作者 Jiangtao Li Xingchen Wang Xuezhen Zhang 《Earthquake Science》 2024年第2期93-106,共14页
Lithospheric structure beneath the northeastern Qinghai-Xizang Plateau is of vital significance for studying the geodynamic processes of crustal thickening and expansion of the Qinghai-Xizang Plateau. We conducted a j... Lithospheric structure beneath the northeastern Qinghai-Xizang Plateau is of vital significance for studying the geodynamic processes of crustal thickening and expansion of the Qinghai-Xizang Plateau. We conducted a joint inversion of receiver functions and surface wave dispersions with P-wave velocity constraints using data from the Chin Array Ⅱ temporary stations deployed across the Qinghai-Xizang Plateau. Prior to joint inversion, we applied the H-κ-c method(Li JT et al., 2019) to the receiver function data in order to correct for the back-azimuthal variations in the arrival times of Ps phases and crustal multiples caused by crustal anisotropy and dipping interfaces. High-resolution images of vS, crustal thickness, and vP/vSstructures in the Qinghai-Xizang Plateau were simultaneously derived from the joint inversion. The seismic images reveal that crustal thickness decreases outward from the Qinghai-Xizang Plateau. The stable interiors of the Ordos and Alxa blocks exhibited higher velocities and lower crustal vP/vSratios. While, lower velocities and higher vP/vSratios were observed beneath the Qilian Orogen and Songpan-Ganzi terrane(SPGZ), which are geologically active and mechanically weak, especially in the mid-lower crust.Delamination or thermal erosion of the lithosphere triggered by hot asthenospheric flow contributes to the observed uppermost mantle low-velocity zones(LVZs) in the SPGZ. The crustal thickness, vS, and vP/vSratios suggest that whole lithospheric shortening is a plausible mechanism for crustal thickening in the Qinghai-Xizang Plateau, supporting the idea of coupled lithospheric-scale deformation in this region. 展开更多
关键词 joint inversion receiver functions surface waves crustal thickness vP/vS ratio NE Qinghai-Xizang Plateau
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Classification of Service Functions in the Life Circle of Beijing Subway Line 7
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作者 SUN Shuai XIANG Zixiong 《Journal of Landscape Research》 2024年第4期21-26,共6页
As a key node for the surrounding area,metro stations are closely connected with the surrounding urban space and develop cooperatively.Different types of metro stations have differences in land use and functional posi... As a key node for the surrounding area,metro stations are closely connected with the surrounding urban space and develop cooperatively.Different types of metro stations have differences in land use and functional positioning.This paper mainly used the methods of Tyson polygon,kernel density analysis and correlation analysis,based on POI data,to classify the stations of Beijing Metro Line 7.This paper made a detailed analysis of commercial subway stations,and analyzed the distribution characteristics of commercial metro stations on Line 7. 展开更多
关键词 POI data Kernel density analysis Correlation analysis Function analysis around metro station
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Role of Immune Cells and Non-immune Cells with Immune Functions in the Pathogenesis of ALI/ARDS
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作者 Jincun LI Wenyu MA Gang LI 《Medicinal Plant》 2024年第4期51-58,共8页
This review outlines the effects of different types of cells with immune function on acute lung injury(ALI)inflammation and the regulation of inflammatory responses between these cells via cell-cell interactions.It is... This review outlines the effects of different types of cells with immune function on acute lung injury(ALI)inflammation and the regulation of inflammatory responses between these cells via cell-cell interactions.It is expected to provide some possible strategies for the research and treatment of ALI and acute respiratory distress syndrome(ARDS). 展开更多
关键词 Acute lung injury(ALI) Immune cell Non-immune cells with immune functions Cell-cell interaction PATHOGENESIS
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Enhancing Proficiency in Quadratic Equations and Functions Through the MILAPlus Strategy
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作者 Rolando S.Merle 《Journal of Contemporary Educational Research》 2024年第1期221-232,共12页
This study investigates the efficacy of the Mathematics Independent Learning Activity Practice and Play Unite Scheme(MILAPlus)as an instructional strategy to improve the proficiency levels of Grade 9 students in quadr... This study investigates the efficacy of the Mathematics Independent Learning Activity Practice and Play Unite Scheme(MILAPlus)as an instructional strategy to improve the proficiency levels of Grade 9 students in quadratic equations and functions through a study carried out at Quezon National High School.The research involved 116 Grade 9 students and utilized a quantitative approach,incorporating both pre-assessment and post-assessment measures.The research utilizes a quasi-experimental design,examining the academic performance of students before and after the introduction of MILAPlus.The pre-assessment establishes a baseline,and the subsequent post-assessment measures the impact of the instructional strategy.Statistical analyses,including t-tests,assess the significance of differences in mean scores and mean percentage scores,providing quantitative insights into the effectiveness of MILAPlus.Findings from the study revealed a statistically significant improvement in both mean scores and mean percentage scores after the utilization of MILAPlus,indicating enhanced proficiency in quadratic equations and functions.The Mean Proficiency Scores(MPS)also showed a substantial increase,demonstrating a marked improvement in overall proficiency levels among Grade 9 students.In light of the results,recommendations were given including the continued utilization of MILAPlus as an instructional strategy and aligning its development with prescribed learning competencies.Emphasizing the consistent adherence to policies and guidelines for MILAPlus implementation is suggested for sustaining positive effects on students’long-term performance in mathematics.This research contributes valuable insights into the practical application and effectiveness of MILAPlus within the context of Grade 9 mathematics education at Quezon National High School. 展开更多
关键词 Mathematics Independent Learning Activity Practice and Play Unite Scheme PRofICIENCY Quadratic equations and functions
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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 ELECTRON POSITRON Wave Function Solution Electromagnetic Spin Mass Charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3D Model Schrödinger Equation RMS KLEIN GORDON Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field Density Phase Flow Attraction REPULSION Shell theorem Ehrenfest VIRIAL Normalization Harmonic Oscillator
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High-throughput calculations combining machine learning to investigate the corrosion properties of binary Mg alloys 被引量:3
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作者 Yaowei Wang Tian Xie +4 位作者 Qingli Tang Mingxu Wang Tao Ying Hong Zhu Xiaoqin Zeng 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第4期1406-1418,共13页
Magnesium(Mg)alloys have shown great prospects as both structural and biomedical materials,while poor corrosion resistance limits their further application.In this work,to avoid the time-consuming and laborious experi... Magnesium(Mg)alloys have shown great prospects as both structural and biomedical materials,while poor corrosion resistance limits their further application.In this work,to avoid the time-consuming and laborious experiment trial,a high-throughput computational strategy based on first-principles calculations is designed for screening corrosion-resistant binary Mg alloy with intermetallics,from both the thermodynamic and kinetic perspectives.The stable binary Mg intermetallics with low equilibrium potential difference with respect to the Mg matrix are firstly identified.Then,the hydrogen adsorption energies on the surfaces of these Mg intermetallics are calculated,and the corrosion exchange current density is further calculated by a hydrogen evolution reaction(HER)kinetic model.Several intermetallics,e.g.Y_(3)Mg,Y_(2)Mg and La_(5)Mg,are identified to be promising intermetallics which might effectively hinder the cathodic HER.Furthermore,machine learning(ML)models are developed to predict Mg intermetallics with proper hydrogen adsorption energy employing work function(W_(f))and weighted first ionization energy(WFIE).The generalization of the ML models is tested on five new binary Mg intermetallics with the average root mean square error(RMSE)of 0.11 eV.This study not only predicts some promising binary Mg intermetallics which may suppress the galvanic corrosion,but also provides a high-throughput screening strategy and ML models for the design of corrosion-resistant alloy,which can be extended to ternary Mg alloys or other alloy systems. 展开更多
关键词 Mg intermetallics Corrosion property HIGH-THROUGHPUT Density functional theory Machine learning
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Structural properties of residual carbon in coal gasification fine slag and their influence on flotation separation and resource utilization:A review 被引量:5
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作者 Rui Han Anning Zhou +4 位作者 Ningning Zhang Kaiqiang Guo Mengyan Cheng Heng Chen Cuicui Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期217-230,共14页
Coal gasification fine slag(FS)is a typical solid waste generated in coal gasification.Its current disposal methods of stockpil-ing and landfilling have caused serious soil and ecological hazards.Separation recovery a... Coal gasification fine slag(FS)is a typical solid waste generated in coal gasification.Its current disposal methods of stockpil-ing and landfilling have caused serious soil and ecological hazards.Separation recovery and the high-value utilization of residual carbon(RC)in FS are the keys to realizing the win-win situation of the coal chemical industry in terms of economic and environmental benefits.The structural properties,such as pore,surface functional group,and microcrystalline structures,of RC in FS(FS-RC)not only affect the flotation recovery efficiency of FS-RC but also form the basis for the high-value utilization of FS-RC.In this paper,the characteristics of FS-RC in terms of pore structure,surface functional groups,and microcrystalline structure are sorted out in accordance with gasification type and FS particle size.The reasons for the formation of the special structural properties of FS-RC are analyzed,and their influence on the flotation separation and high-value utilization of FS-RC is summarized.Separation methods based on the pore structural characterist-ics of FS-RC,such as ultrasonic pretreatment-pore-blocking flotation and pore breaking-flocculation flotation,are proposed to be the key development technologies for improving FS-RC recovery in the future.The design of low-cost,low-dose collectors containing polar bonds based on the surface and microcrystalline structures of FS-RC is proposed to be an important breakthrough point for strengthening the flotation efficiency of FS-RC in the future.The high-value utilization of FS should be based on the physicochemical structural proper-ties of FS-RC and should focus on the environmental impact of hazardous elements and the recyclability of chemical waste liquid to es-tablish an environmentally friendly utilization method.This review is of great theoretical importance for the comprehensive understand-ing of the unique structural properties of FS-RC,the breakthrough of the technological bottleneck in the efficient flotation separation of FS,and the expansion of the field of the high value-added utilization of FS-RC. 展开更多
关键词 coal gasification fine slag residual carbon pore structure surface functional groups microcrystalline structure flotation sep-aration resource utilization
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Study on the efficacy of early treatment with pirfenidone on the lung function of patients with idiopathic pulmonary fibrosis 被引量:2
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作者 Ying Lei Jian-Hui Sheng +3 位作者 Xu-Ru Jin Xian-Bing Liu Xiao-Yan Zheng Xiao-Hua Xu 《World Journal of Clinical Cases》 SCIE 2024年第22期4913-4923,共11页
BACKGROUND Idiopathic pulmonary fibrosis(IPF)is classified under fibrotic interstitial pneumonia,characterized by a chronic and progressive course.The predominant clinical features of IPF include dyspnea and pulmonary... BACKGROUND Idiopathic pulmonary fibrosis(IPF)is classified under fibrotic interstitial pneumonia,characterized by a chronic and progressive course.The predominant clinical features of IPF include dyspnea and pulmonary dysfunction.AIM To assess the effects of pirfenidone in the early treatment of IPF on lung function in patients.METHODS A retrospective analysis was performed on 113 patients with IPF who were treated in our hospital from November 2017 to January 2023.These patients were divided into two groups:control group(n=53)and observation group(n=60).In the control group,patients received routine therapy in combination with methylprednisolone tablets,while those in the observation group received routine therapy together with pirfenidone.After applying these distinct treatment approaches to the two groups,we assessed several parameters,including the overall effectiveness of clinical therapy,the occurrence of adverse reactions(e.g.,nausea,vomiting,and anorexia),symptom severity scores,pulmonary function index levels,inflammatory marker levels,and the 6-min walk distance before and after treatment in both groups.RESULTS The observation group exhibited significantly higher rates than the control group after therapy,with a clear distinction(P<0.05).After treatment,the observation group experienced significantly fewer adverse reactions than the control group,with a noticeable difference(P<0.05).When analyzing the symptom severity scores between the two groups of patients after treatment,the observation group had significantly lower scores than the control group,with a distinct difference(P<0.05).When comparing the pulmonary function index levels between the two groups of patients after therapy,the observation group displayed significantly higher levels than the control group,with a noticeable difference(P<0.05).Evaluating the inflammatory marker data(C-reactive protein,interleukin-2[IL-2],and IL-8)between the two groups of patients after therapy,the observation group exhibited significantly lower levels than the control group,with significant disparities(P<0.05).Comparison of the 6-min walking distance data between the two groups of patients after treatment showed that the observation group achieved significantly greater distances than the control group,with a marked difference(P<0.05).CONCLUSION Prompt initiation of pirfenidone treatment in individuals diagnosed with IPF can enhance pulmonary function,elevate inflammatory factor levels,and increase the distance covered in the 6-min walk test.This intervention is conducive to effectively decreasing the occurrence of adverse reactions in patients. 展开更多
关键词 Pirfenidone Early intervention Idiopathic pulmonary fibrosis Pulmonary function Effect evaluation
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Characteristics and Influencing Factors of Microplastics in Snow in the Inner Mongolia Plateau, China 被引量:1
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作者 Hongwei Yu Junrong Shao +3 位作者 Huawei Jia Diga Gang Baiwen Ma Chengzhi Hu 《Engineering》 SCIE EI CAS CSCD 2024年第6期69-77,共9页
Microplastics(MPs;<5 mm)have become one of the most prominent global environmental pollution problems.MPs can spread to high altitudes through atmospheric transport and can be deposited by rainfall or snowfall,pote... Microplastics(MPs;<5 mm)have become one of the most prominent global environmental pollution problems.MPs can spread to high altitudes through atmospheric transport and can be deposited by rainfall or snowfall,potentially threatening the structure and function of natural ecosystems.MPs in terrestrial and aquatic ecosystems alter the growth and functional characteristics of organisms.However,little attention has been given to the possible harm associated with MPs deposited in snow,particularly in the context of global climate warming.MPs collected from surface snow in the Inner Mongolia Plateau,China,were used for quantitative analysis and identification.The results showed that MPs were easily detected,and the related concentration was approximately(68±10)–(199±22)MPsL1 in snow samples.Fibers were the most common morphology,the polymer composition was largely varied,and the abundance and composition of MPs were linked to human activity to a great extent.High-throughput sequencing results showed that the composition and abundance of microorganisms also differed in snow samples from areas with different MP pollution characteristics,indicating a considerable difference in microbial functional diversity.MPs may have an interference effect on the individual growth and functional expression of microorganisms in snow.In addition,the results showed that functional living areas(e.g.,landfills and suburban areas)in cities play an important role in the properties of MPs.For instance,the highest abundance of MPs was found in thermal power plants,whereas the abundance of polymers per sample was significantly lower in the suburban area.The MP contaminants hidden in snow can alter microbial structure and function and are therefore a potential threat to ecosystem health. 展开更多
关键词 Human activities SNOW Microplastics Microbial community Urban function Environmental effect
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Overexpression of the transcription factor MdWRKY115 improves drought and osmotic stress tolerance by directly binding to the MdRD22 promoter in apple 被引量:1
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作者 Qinglong Dong Yi Tian +9 位作者 Xuemei Zhang Dingyue Duan He Zhang Kaiyu Yang Peng Jia Haoan Luan Suping Guo Guohui Qi Ke Mao Fengwang Ma 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第3期629-640,共12页
Abiotic stress reduces plant yield and quality.WRKY transcription factors play key roles in abiotic stress responses in plants,but the molecular mechanisms by which WRKY transcription factors mediate responses to drou... Abiotic stress reduces plant yield and quality.WRKY transcription factors play key roles in abiotic stress responses in plants,but the molecular mechanisms by which WRKY transcription factors mediate responses to drought and osmotic stresses in apple(Malus×domestica Borkh.)remain unclear.Here,we functionally characterized the apple GroupⅢWRKY gene MdWRKY115.qRT-PCR analysis showed that MdWRKY115 expression was up-regulated by drought and osmotic stresses.GUS activity analysis revealed that the promoter activity of MdWRKY115 was enhanced under osmotic stress.Subcellular localization and transactivation assays indicated that MdWRKY115 was localized to the nucleus and had a transcriptional activity domain at the N-terminal region.Transgenic analysis revealed that the overexpression of MdWRKY115 in Arabidopsis plants and in apple callus markedly enhanced their tolerance to drought and osmotic stresses.DNA affinity purification sequencing showed that MdWRKY115 binds to the promoter of the stress-related gene MdRD22.This binding was further verified by an electrophoretic mobility shift assay.Collectively,these findings suggest that MdWRKY115 is an important regulator of osmotic and drought stress tolerance in apple. 展开更多
关键词 APPLE MdWRKY115 Osmotic stress Drought stress Function analysis
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A facile strategy for tuning the density of surface-grafted biomolecules for melt extrusion-based additive manufacturing applications 被引量:1
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作者 I.A.O.Beeren G.Dos Santos +8 位作者 P.J.Dijkstra C.Mota J.Bauer H.Ferreira Rui L.Reis N.Neves S.Camarero-Espinosa M.B.Baker L.Moroni 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第3期277-291,共15页
Melt extrusion-based additive manufacturing(ME-AM)is a promising technique to fabricate porous scaffolds for tissue engi-neering applications.However,most synthetic semicrystalline polymers do not possess the intrinsi... Melt extrusion-based additive manufacturing(ME-AM)is a promising technique to fabricate porous scaffolds for tissue engi-neering applications.However,most synthetic semicrystalline polymers do not possess the intrinsic biological activity required to control cell fate.Grafting of biomolecules on polymeric surfaces of AM scaffolds enhances the bioactivity of a construct;however,there are limited strategies available to control the surface density.Here,we report a strategy to tune the surface density of bioactive groups by blending a low molecular weight poly(ε-caprolactone)5k(PCL5k)containing orthogonally reactive azide groups with an unfunctionalized high molecular weight PCL75k at different ratios.Stable porous three-dimensional(3D)scaf-folds were then fabricated using a high weight percentage(75 wt.%)of the low molecular weight PCL 5k.As a proof-of-concept test,we prepared films of three different mass ratios of low and high molecular weight polymers with a thermopress and reacted with an alkynated fluorescent model compound on the surface,yielding a density of 201-561 pmol/cm^(2).Subsequently,a bone morphogenetic protein 2(BMP-2)-derived peptide was grafted onto the films comprising different blend compositions,and the effect of peptide surface density on the osteogenic differentiation of human mesenchymal stromal cells(hMSCs)was assessed.After two weeks of culturing in a basic medium,cells expressed higher levels of BMP receptor II(BMPRII)on films with the conjugated peptide.In addition,we found that alkaline phosphatase activity was only significantly enhanced on films contain-ing the highest peptide density(i.e.,561 pmol/cm^(2)),indicating the importance of the surface density.Taken together,these results emphasize that the density of surface peptides on cell differentiation must be considered at the cell-material interface.Moreover,we have presented a viable strategy for ME-AM community that desires to tune the bulk and surface functionality via blending of(modified)polymers.Furthermore,the use of alkyne-azide“click”chemistry enables spatial control over bioconjugation of many tissue-specific moieties,making this approach a versatile strategy for tissue engineering applications. 展开更多
关键词 Additive manufacturing BLENDING Surface functionalization Surface density Click chemistry HUMAN
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Pathological and therapeutic effects of extracellular vesicles in neurological and neurodegenerative diseases 被引量:2
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作者 Paula lzquierdo-Altarejos Victoria Moreno-Manzano Vicente Felipo 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第1期55-61,共7页
Extracellular vesicles are released by all cell types and contain proteins,microRNAs,mRNAs,and other bioactive molecules.Extracellular vesicles play an important role in intercellular communication and in the modulati... Extracellular vesicles are released by all cell types and contain proteins,microRNAs,mRNAs,and other bioactive molecules.Extracellular vesicles play an important role in intercellular communication and in the modulation of the immune system and neuroinflammation.The cargo of extra cellular vesicles(e.g.,proteins and microRNAs)is altered in pathological situations.Extracellular vesicles contribute to the pathogenesis of many pathologies associated with sustained inflammation and neuroinflammation,including cance r,diabetes,hype rammonemia and hepatic encephalopathy,and other neurological and neurodegenerative diseases.Extracellular vesicles may cross the blood-brain barrier and transfer pathological signals from the periphery to the brain.This contributes to inducing neuroinflammation and cognitive and motor impairment in hyperammonemia and hepatic encephalopathy and in neurodegenerative diseases.The mechanisms involved are beginning to be unde rstood.For example,increased tumor necrosis factor a in extracellular vesicles from plasma of hype rammonemic rats induces neuroinflammation and motor impairment when injected into normal rats.Identifying the mechanisms by which extracellular vesicles contribute to the pathogenesis of these diseases will help to develop new treatments and diagnostic tools for their easy and early detection.In contrast,extra cellular vesicles from mesenchymal stem cells have therapeutic utility in many of the above pathologies,by reducing inflammation and neuroinflammation and improving cognitive and motor function.These extra cellular vesicles recapitulate the beneficial effects of mesenchymal stem cells and have advantages as therapeutic tools:they are less immunoge nic,may not diffe rentiate to malignant cells,cross the blood-brain barrier,and may reach more easily target organs.Extracellular vesicles from mesenchymal stem cells have beneficial effects in models of ischemic brain injury,Alzheimer's and Parkinson's diseases,hyperammonemia,and hepatic encephalopathy.Extracellular vesicles from mesenchymal stem cells modulate the immune system,promoting the shift from a pro-inflammato ry to an anti-inflammatory state.For example,extracellular vesicles from mesenchymal stem cells modulate the Th17/Treg balance,promoting the anti-inflammatory Treg.Extracellular vesicles from mesenchymal stem cells may also act directly in the brain to modulate microglia activation,promoting a shift from a pro-inflammatory to an anti-inflammatory state.This reduces neuroinflammation and improves cognitive and motor function.Two main components of extracellular vesicles from mesenchymal stem cells which contribute to these beneficial effects are transforming growth factor-βand miR-124.Identifying the mechanisms by which extracellular vesicles from mesenchymal stem cells induce the beneficial effects and the main molecules(e.g.,proteins and mRNAs)involved may help to improve their therapeutic utility.The aims of this review are to summarize the knowledge of the pathological effects of extracellular vesicles in different pathologies,the therapeutic potential of extra cellular vesicles from mesenchymal stem cells to recover cognitive and motor function and the molecular mechanisms for these beneficial effects on neurological function. 展开更多
关键词 extracellular vesicles INFLAMMATION cognitive function mesenchymal stem cells neurodegenerative diseases NEUROINFLAMMATION theRAPY transforming growth factor-β
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Transplantation of fibrin-thrombin encapsulated human induced neural stem cells promotes functional recovery of spinal cord injury rats through modulation of the microenvironment 被引量:2
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作者 Sumei Liu Baoguo Liu +4 位作者 Qian Li Tianqi Zheng Bochao Liu Mo Li Zhiguo Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期440-446,共7页
Recent studies have mostly focused on engraftment of cells at the lesioned spinal cord,with the expectation that differentiated neurons facilitate recovery.Only a few studies have attempted to use transplanted cells a... Recent studies have mostly focused on engraftment of cells at the lesioned spinal cord,with the expectation that differentiated neurons facilitate recovery.Only a few studies have attempted to use transplanted cells and/or biomaterials as major modulators of the spinal cord injury microenvironment.Here,we aimed to investigate the role of microenvironment modulation by cell graft on functional recovery after spinal cord injury.Induced neural stem cells reprogrammed from human peripheral blood mononuclear cells,and/or thrombin plus fibrinogen,were transplanted into the lesion site of an immunosuppressed rat spinal cord injury model.Basso,Beattie and Bresnahan score,electrophysiological function,and immunofluorescence/histological analyses showed that transplantation facilitates motor and electrophysiological function,reduces lesion volume,and promotes axonal neurofilament expression at the lesion core.Examination of the graft and niche components revealed that although the graft only survived for a relatively short period(up to 15 days),it still had a crucial impact on the microenvironment.Altogether,induced neural stem cells and human fibrin reduced the number of infiltrated immune cells,biased microglia towards a regenerative M2 phenotype,and changed the cytokine expression profile at the lesion site.Graft-induced changes of the microenvironment during the acute and subacute stages might have disrupted the inflammatory cascade chain reactions,which may have exerted a long-term impact on the functional recovery of spinal cord injury rats. 展开更多
关键词 biomaterial FIBRINOGEN functional recovery induced neural stem cell transplantation MICROENVIRONMENT MICROGLIA spinal cord injury THROMBIN
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Responses of growth performance,antioxidant function,small intestinal morphology and mRNA expression of jejunal tight junction protein to dietary iron in yellow-feathered broilers 被引量:1
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作者 Kaiwen Lei Hao Wu +4 位作者 Jerry W Spears Xi Lin Xi Wang Xue Bai Yanling Huang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1329-1337,共9页
This study aimed to investigate the dose-effect of iron on growth performance,antioxidant function.intestinal morphology,and mRNA expression of jejunal tight junction protein in 1-to21-d-old yellow-feathered broilers.... This study aimed to investigate the dose-effect of iron on growth performance,antioxidant function.intestinal morphology,and mRNA expression of jejunal tight junction protein in 1-to21-d-old yellow-feathered broilers.A total of 7201-d-old yellow-feathered maleb roilers were allocated to 9 treatments with 8 replicate cages of 10 birds per cage.The dietary treatments were consisted of a basal diet(contained 79.6 mg Fe kg^(-1))supplemented with 0,20,40,60,80,160,320,640,and 1,280 mg Fe kg^(-1)in the form of FeSO_(4)·7H_(2)O.Compared with the birds in the control group,birds supplemented with 20mg Fe kg^(-1)had higher average daily gain(ADG)(P<0.0001).Adding 640 and 1,280 mg Fe kg^(-1)significantly decreased ADG(P<0.0001)and average daily feed intake(ADFI)(P<0.0001)compared with supplementation of 20mg Fe kg^(-1).Malondialdehyde(MDA)concentration in plasma and duodenum increased linearly(P<0.0001),but MDA concentration in liver and jejunum increased linearly(P<0.05)or quadratically(P<0.05)with increased dietary Fe concentration.The villus height(VH)in duodenum and jejunum,and the ratio of villus height to crypt depth(V/C)in duodenum decreased linearly(P?0.05)as dietary Feincreased.As dietary Fe increased,the jejunal relative mRNA abundance of claudin-1 decreased linearly(P=0.001),but the jejunal relative mRNA abundance of zona occludens-1(ZO-1)and occludin decreased linearly(P?0.05)or quadratically(P?0.05).Compared with the supplementation of 20 mg Fe kg^(-1),the supplementation of640 mg Fe kg^(-1)or higher increased(P?0.05)MDA concentrations in plasma,duodenum,and jejunum,decreased VH in the duodenum and jejunum,and the addition of 1,280 mg Fe kg^(-1)reduced(P?0.05)the jejunal tight junction protein(claudin-1,ZO-1,occludin)mRNA abundance.In summary,640 mg of supplemental Fe kg^(-1)or greater was associated with decreased growth performance,increased oxidative stress,disrupted intestinal morphology,and reduced mRNA expression of jejunal tight junction protein. 展开更多
关键词 IRON yellow-feathered broiler antioxidant function intestinal morphology tight junction protein
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Impact of propofol and sevoflurane anesthesia on cognition and emotion in gastric cancer patients undergoing radical resection 被引量:2
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作者 Ao-Han Li Su Bu +2 位作者 Ling Wang Ai-Min Liang Hui-Yu Luo 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第1期79-89,共11页
BACKGROUND Propofol and sevoflurane are commonly used anesthetic agents for maintenance anesthesia during radical resection of gastric cancer.However,there is a debate concerning their differential effects on cognitiv... BACKGROUND Propofol and sevoflurane are commonly used anesthetic agents for maintenance anesthesia during radical resection of gastric cancer.However,there is a debate concerning their differential effects on cognitive function,anxiety,and depression in patients undergoing this procedure.AIM To compare the effects of propofol and sevoflurane anesthesia on postoperative cognitive function,anxiety,depression,and organ function in patients undergoing radical resection of gastric cancer.METHODS A total of 80 patients were involved in this research.The subjects were divided into two groups:Propofol group and sevoflurane group.The evaluation scale for cognitive function was the Loewenstein occupational therapy cognitive assessment(LOTCA),and anxiety and depression were assessed with the aid of the self-rating anxiety scale(SAS)and self-rating depression scale(SDS).Hemodynamic indicators,oxidative stress levels,and pulmonary function were also measured.RESULTS The LOTCA score at 1 d after surgery was significantly lower in the propofol group than in the sevoflurane group.Additionally,the SAS and SDS scores of the sevoflurane group were significantly lower than those of the propofol group.The sevoflurane group showed greater stability in heart rate as well as the mean arterial pressure compared to the propofol group.Moreover,the sevoflurane group displayed better pulmonary function and less lung injury than the propofol group.CONCLUSION Both propofol and sevoflurane could be utilized as maintenance anesthesia during radical resection of gastric cancer.Propofol anesthesia has a minimal effect on patients'pulmonary function,consequently enhancing their postoperative recovery.Sevoflurane anesthesia causes less impairment on patients'cognitive function and mitigates negative emotions,leading to an improved postoperative mental state.Therefore,the selection of anesthetic agents should be based on the individual patient's specific circumstances. 展开更多
关键词 PROPofOL SEVofLURANE Radical resection of gastric cancer Anesthetic effect Cognitive function Negative emotion
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Deep brain implantable microelectrode arrays for detection and functional localization of the subthalamic nucleus in rats with Parkinson’s disease 被引量:1
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作者 Luyi Jing Zhaojie Xu +11 位作者 Penghui Fan Botao Lu Fan Mo Ruilin Hu Wei Xu Jin Shan Qianli Jia Yuxin Zhu Yiming Duan Mixia Wang Yirong Wu Xinxia Cai 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第4期439-452,共14页
The subthalamic nucleus(STN)is considered the best target for deep brain stimulation treatments of Parkinson’s disease(PD).It is difficult to localize the STN due to its small size and deep location.Multichannel micr... The subthalamic nucleus(STN)is considered the best target for deep brain stimulation treatments of Parkinson’s disease(PD).It is difficult to localize the STN due to its small size and deep location.Multichannel microelectrode arrays(MEAs)can rapidly and precisely locate the STN,which is important for precise stimulation.In this paper,16-channel MEAs modified with multiwalled carbon nanotube/poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(MWCNT/PEDOT:PSS)nanocomposites were designed and fabricated,and the accurate and rapid identification of the STN in PD rats was performed using detection sites distributed at different brain depths.These results showed that nuclei in 6-hydroxydopamine hydrobromide(6-OHDA)-lesioned brains discharged more intensely than those in unlesioned brains.In addition,the MEA simultaneously acquired neural signals from both the STN and the upper or lower boundary nuclei of the STN.Moreover,higher values of spike firing rate,spike amplitude,local field potential(LFP)power,and beta oscillations were detected in the STN of the 6-OHDA-lesioned brain,and may therefore be biomarkers of STN localization.Compared with the STNs of unlesioned brains,the power spectral density of spikes and LFPs synchronously decreased in the delta band and increased in the beta band of 6-OHDA-lesioned brains.This may be a cause of sleep and motor disorders associated with PD.Overall,this work describes a new cellular-level localization and detection method and provides a tool for future studies of deep brain nuclei. 展开更多
关键词 Functional localization Implantable microelectrode arrays Parkinson’s disease Subthalamic nucleus
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