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Impact of Polymer Matrix on Polymer Mechanochromism from Excited State Intramolecular Proton Transfer

Chinese Journal of Chemistry 2024年第6期42卷 611-616页

作者： Yu Wu Xin Cheng huan hu Shui hu Zhimin Ma Zhiyong Ma Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing State Key Laboratory of Organic-Inorganic CompositesCollege of Chemical EngineeringBeijing University of Chemical TechnologyBeijing100029 China Center of Advanced Elastomer Materials College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing100029 China College of Engineering Peking UniversityBeijing100871 China

Mechanochromic polymers based on non-covalent changes have attracted much attention recently.Herein,we report the impact of inter/intramolecular hydrogen bonds on polymer mechanochromism from the excited state intramolecular proton transfer (ESIPT) process.PhMz-NH2-OH and PhMz=2A are designed and obtained by simple and high-yield synthesis,and are connected into polyurethane and poly(methyl acrylate-co-2-ethylhexyl acrylate),respectively.In the initial state,the PhMz-NH2-OH@PU sample shows blue fluorescence from the excited enol form (E*) excitons,owing to intermolecular hydrogen bonds that interrupt the ESIPT reactions but the PhMz=2A@PMA-2-EA sample expresses cyan fluorescence belonging to the excited keto form (K*) emission,implying that the intramolecular hydrogen bonds matter.Furthermore,under stretching,external force can tune the emission of the PhMz=2A@PMA-2-EA sample from K* to E* state.Though external force can putatively still promote a bond rotation,ESIPT reactions remain equivalently interrupted in both the relaxed and stressed states in a hydrogen-bond donating environment.DFT calculation confirms the force-induced increase in dihedral angle for the transition of ESIPT-on/off.Thus,PhMz-NH2-OH@PU and PhMz=2A@PMA-2-EA showed disparate initial ESIPT states and further different responses/sensitivity to force.This study reports a novel and efficient strategy for enriching mechanochromic investigation and extending the applications of ESIPT reactions.

关键词： Polymer mechanochromism Excited state intramolecular proton transfer Hydrogen bonding Supramolecular chemistry Elastomers

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Sperm acrosin activity may be a useful factor in choosing between ICSI and IVF for infertile male patients

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Asian Journal of Andrology 2024年第1期26卷 85-90页

作者： Ye-Na hu Liang hu Xin-Yu Yin huan Zhang Yang-Qin Peng Gang Liu Ge Lin Wei-Na Li The Institute of Reproductive and Stem Cell Engineering School of Basic Medical ScienceCentral South UniversityChangsha 410008China Department of Andrology Reproductive and Genetic Hospital of CITiC-XiangyaChangsha 410013China Clinical Research Center for Reproduction and Genetics in hunan Province Changsha 410013China hunan Guangxiu Hi-tech Life Technology Co. Ltd.Changsha 410013China

The clinical applications of acrosin activity are limited.We analyzed 61578 male partners in infertile couples who visited the outpatient department of the Reproductive and Genetic Hospital of CITIC-Xiangya(Changsha,China)between August 2014 and December 2019 to determine the reference ranges and thresholds for acrosin activity in infertile Chinese men;to determine whether correlations exist between acrosin activity and age,sperm concentration,sperm morphology,or sperm motility;and to evaluate whether acrosin activity could serve as an effective prognostic indicator for choosing between in vitro fertilization(IvF)and intracytoplasmic sperm injection(icsl)in the clinic.The cut-off value for the normal reference range of acrosin activity for male partners in infertile couples was 24.78μlU per 106 sperm.There was no significant association between acrosin activity and age,sperm concentration,semen volume,total sperm count,progressive motility,or total motile spermatozoa.A weak positive correlation was found between acrosin activity and normal sperm morphology.There was a statistically significant difference in abnormal acrosome morphology between the group with high acrosin activity(>24.78μlU per 106 sperm)and the group with low acrosin activity(<24.78μlU per 106 sperm).The group with a low IVF fertilization rate had a high index of abnormal acrosomal morphology at 21.2%,while the group with a high IVF fertilization rate had a low index of 0.2%.At an acrosin activity of<24.78μlU per 10 sperm,in one cycle of the same patient,the fertilization rate,normal fertilization rate,and good-quality embryo rate for Icsl were significantly higher than those for IVF.Therefore,the most promising application of acrosin activity could be in the selection of IcsI over IVF for infertile male patients with complete fertilization failure or a low fertilization rate.

关键词： acrosin activity fertilization rate ICSI IVF semen parameters

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How aging affects bone health via the intestinal micro-environment

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BIOCELL 2024年第3期48卷 353-362页

作者： huan hu YUE huanG FANGZHOU LIU QIAN WANG YANZI YAO School of Stomatology Zunyi Medical UniversityZunyiChina Microbial Resources and Drug Development Key Laboratory of Guizhou Tertiary Institution Zunyi Medical UniversityZunyiChina Department of Stomatology Luoyang Maternal and Child Health HospitalLuoyangChina

Increasing life expectancy and an aging population lead to age-related bone diseases like osteoporosis and low bone mass more prevalent.These conditions represent a common,costly and chronic burden,not only for elderly but also to society at large.Consequently,elucidating the pathophysiology and developing effective therapies for these diseases is of paramount importance.Recent advances in research have identiﬁed the gut as a novel and promising target for addressing bone disorders,giving rise to the concept of the“gut-bone axis”.An in-depth review of the latest insights into the effects of age-related physiological changes in the gastrointestinal tract on bone health is presented in this article.It examines how the“gut-bone”axis interacts with bone aging across various domains,including metabolism,nutrition,intestinal permeability,immunity,and oxidative stress.

关键词： Gut barrier Skeletal system Senescent Gut-bone axis Gut microbiota

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Dynamic changes in physicochemical property,biogenic amines content and microbial diversity during the fermentation of Sanchuan ham

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Food Science and human Wellness 2024年第1期13卷 506-516页

作者： Zhongai Chen Hong Chen huan Du Cong Chen Kaixiang Lu Qiaoli Xue Yongjin hu College of Food Science and Technology Yunnan Agricultural UniversityKunming 650000China Institute of Food Processing Guizhou Academy of Agricultural SciencesGuiyang 550006China Editorial Department of Journal of Yunnan Agricultural University Yunnan Agricultural UniversityKunming 650000China

Sanchuan ham is appreciated in Yunnan Province,China,for its characteristic flavor and taste,while the microbial community structure and biogenic amines content remain unclear during fermentation processes.In this study,we explored the physicochemical property,biogenic amines concentration and microbial diversity of external and internal Sanchuan ham by high-throughput sequencing during the processing of Sanchuan ham.Results showed that the nitrite remained at a stable level of 0.15 mg/kg which was significantly lower than the national health standard safety level of 20 mg/kg.In addition,compared with fresh hams,the content of total free amino acids in ripe Sanchuan ham has grown 14 folds;sour and bitter were the main tastes of Sanchuan ham.Notably,the concentration of cadaverine was the highest of all biogenic amines during the entire fermentation period.At the bacterial phyla level,Firmicutes and Actinobacteria were the two main phyla,while at the genus level,Staphylococcus was a significant strain throughout the whole fermentation.Moreover,the dry stage has a great impact on the succession change of microbial community structure.Simultaneously,the change trends and composition of bacteria in the interior have slight discrepancies with those of the exterior of Sanchuan ham.

关键词： Sanchuan ham Nitrite cont ent Free amino acids Cadaverine Staphylococcus

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Insights into the role of RNA m6 A modification in the metabolic process and related diseases

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Genes & Diseases 2024年第4期11卷 270-295页

作者： Haiming hu Zhibin Li Xia Xie Qiushi Liao Yiyang hu Chunli Gong Nannan Gao huan Yang Yufeng Xiao Yang Chen Department of Gastroenterology Xinqiao HospitalArmy Medical UniversityChongqing 400037China

According to the latest consensus,many traditional diseases are considered meta-bolic diseases,such as cancer,type 2 diabetes,obesity,and cardiovascular disease.Currently,metabolic diseases are increasingly prevalent because of the ever-improving living standards and have become the leading threat to human health.Multiple therapy methods have been applied to treat these diseases,which improves the quality of life of many patients,but the overall effect is still unsatisfactory.Therefore,intensive research on the metabolic process and the pathogenesis of metabolic diseases is imperative.N6-methyladenosine(m°A)is an important modification of eukaryotic RNAs.It is a critical regulator of gene expression that is involved in different cellular functions and physiological processes.Many studies have indi-cated that m6A modification regulates the development of many metabolic processes and metabolic diseases.In this review,we summarized recent studies on the role of m6A modifica-tion in different metabolic processes and metabolic diseases.Additionally,we highlighted the potential m6A-targeted therapy for metabolic diseases,expecting to facilitate m6A-targeted strategies in the treatment of metabolic diseases.

关键词： Cancer m6A-targeted therapy Metabolic disease Metabolism N6-methyladenosine

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Stripping of aggregate from mortar in waste concrete heated by microwave: Mechanisms of differential-temperature stress and vapor expansion pressure

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第3期11卷 538-558页

作者： Yanping Sheng Xiao huan Peizhen hu Liangliang Li Ahmed Abdulakeem Zhoujing Ye Linbing Wang Yanping Yin School of Materials Science and Engineering Chang'an University Engineering Research Center of Transportation Materials Ministry of Education Chang'an University National Center for Materials Service Safety University of Science and Technology Beijing School of Environmental Civil Agricultural and Mechanical Engineering College of Engineering University of Georgia

Microwave heating, which is used for pre-treatment of concrete before it is comminuted,stands as a strong candidate for selective liberation of multiphase materials like concrete.This paper is concerned with the selective liberation of concrete's raw constituents(particularly aggregate) for recycling by considering the water content of concrete as a parameter of microwave heating for the first time. The deterioration law of the concrete's performance was characterized by the variation in the splitting tensile strength and relative dynamic modulus after heating by microwave at different water contents. Besides,tests were conducted to evaluate the performance of the interface transition zone(ITZ)between aggregate and mortar as well as to investigate the reasons for the stripping behavior of aggregate-mortar, which included the interface tensile strength test, temperature measurement, and porosity test. The deterioration law of splitting tensile strength and relative dynamic modulus revealed that the performance of concrete was subject to different degrees of damage depending on the water content. Furthermore, experimental results showed that interface bonding strength between aggregate and mortar was dramatically impaired, and a large temperature difference was generated between the aggregate and mortar during microwave heating. Meanwhile, the permeable pores increased considerably even when the specimens were dried. In the presence of water, the intactness of ITZ between aggregate and mortar was destroyed by microwave heating, and its performance was significantly lowered, which led to the occurrence of stripping behavior between aggregate and mortar. This was reaffirmed by the microstructure presented by scanning electron microscopy. Thus, the newly developed microwave pretreatment improved by providing appropriate water contents for concrete corresponding to different strength grades is a promising method for recycling aggregate from waste concrete.

关键词： Waste concrete Recycled aggregate Microwave heating Stripping behavior Differential-temperature stress Vapor expansion pressure

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Mitogenome-based phylogeny of mosquitoes(Diptera:Culicidae)

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Insect Science 2024年第2期31卷 599-612页

作者： De-Hong Chen Shu-Lin He Wen-Bo Fu Zhen-Tian Yan Yun-Jian hu huan Yuan Ming-Bin Wang Bin Chen Chongqing Key Laboratory of Vector Insects Institute of Entomology and Molecular BiologyChongqing Normal UniversityChongqingChina

Mosquitoes are of great medical significance as vectors of many deadly diseases.Mitogenomes have been widely used in phylogenetic studies,but mitogenome knowledge within the family Culicidae is limited,and Culicidae phylogeny is far from resolved.In this study,we surveyed the mitogenomes of 149 Culicidae species,including 7 newly sequenced species.Comparative analysis of 149 mosquito mitogenomes shows gene composition and order to be identical to that of an ancestral insect,and the AT bias,length variation,and codon usage are all consistent with that of other reported Dipteran mitogenomes.Phylogenetic analyses based on the DNA sequences of the 13 protein-coding genes from the 149 species robustly support the monophyly of the subfamily Anophelinae and the tribes Aedini,Culicini,Mansonini,Sabethini,and Toxorhynchitini.To resolve ambiguous relationships between clades within the subfamily Culicinae,we performed topological tests and show that Aedini is a sister to Culicini and that Uranotaenini is a sister to(Mansonini)+(Toxorhynchitini+Sabethini).In addition,we estimated divergence times using a Bayesian relaxation clock based on the sequence data and 3 fossil calibration points.The results show mosquitoes diverged during the Early Jurassic with massive Culicinae radiations during the Cretaceous,coincident with the emergence of angiosperms and the burst of mammals and birds.Overall,this study,which uses the largest number of Culicidae mitogenomes sequenced to date,comprehensively reveals the mitogenome characteristics and mitogenome-based phylogeny and divergence times of Culicidae,providing information for further studies on the mitogenome,phylogeny,evolution,and taxonomic revision of Culicidae.

关键词： characterization Culicidae evolution mitogenomes mosquitoes phylogeny

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Lignocellulosic fraction-induced niche differentiation within dissimilatory iron reducing bacterial groups in a paddy soil

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Soil Ecology Letters 2024年第1期6卷 77-88页

作者： Yunbin Jiang Wenting hu Kailou Liu Shangshu huang Fengwu Zhou Cheng Han huan Deng Wenhui Zhong Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control School of GeographyNanjing Normal UniversityNanjing 210023China Jiangsu Centerfor Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China National Engineering and Technology Research Center for Red Soil Improvement Jiangxi Institute of Red Soil and Germplasm ResourcesNanchang 331717China Schoolof Environment Nanjing Normal UniversityNanjing 210023China

Responses of soil DIRB to lignocellulosic fractions during a 6-week microcosm incubation were investigated.Anaeromyxobacter,Bacillus,and Clostridium maintained their domi-nance throughout the incubation.Distinct DIRB groups proliferated under specific lignocellulosic fraction amendments.Limits of insufficient ferric iron on the proliferation varied by DIRB group.Dissimilatory iron reducing bacteria(DIRB)are phylogenetically and physi-ologically diverse in paddy soils,where iron reduction closely couples with the oxidation of rice straw-derived carbon in the straw returning scenarios.However,few studies have addressed the niche differentiation within DIRB groups during the degradation of lignocellulosic fractions of rice straw.This study conducted a 6-week microcosm incubation experiment to reveal the distinct responses of DIRB groups under specific lignocellulosic fraction amendments with and without ferrihydrite(Fh)addition in a flooded paddy Ultisol.Results showed that the total absolute abundance of the 19 detected DIRB groups did not vary significantly during the incubation.Anaeromyxobacter,Bacillus,and Clostridium were the dominant DIRB groups for all lignocellulosic treatments whereas Thermincola was dominant but only under xylan amendment with Fh addition.DIRB-nodes in the co-occurrence networks of bacterial community mainly belonged to Anaeromyxobacter and Bacillus.Clostridium and Thermincola,Alkaliphilus and Anaeromyxobacter,and Alicyclobacillus,Desulfobulbus,and Desulfosporosinus were specifically proliferated under xylan,cellulose,and lignin amendments,respectively.Whether the proliferation was limited by insufficient ferric iron varied by bacterial group.These findings suggested the lignocellulosic fraction-induced niche differentiation within DIRB groups,which advanced our understanding of the ecology of DIRB in paddy soils under straw returning.

关键词： cellulose hemicellulose lignin bacterial community diversity co-occurrence networks

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Recent progress of Pt-based oxygen reduction reaction catalysts for proton exchange membrane fuel cells

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Rare Metals 2024年第6期43卷 2444-2468页

作者： Feng Zhan Kun-Song hu Jin-hua Mai Li-Sheng Zhang Zhen-Guo Zhang huan He Xin-hua Liu School of Resources Environment and MaterialsGuangxi University School of Transportation Science and Engineering Beihang University IDTECH (Suzhou) Co.Ltd Dyson School of Design Engineering Imperial College London

With the increasing consumption of fossil fuels,proton exchange membrane fuel cells(PEMFCs) have attracted considerable attention as green and sustainable energy conversion devices.The slow kinetics of the cathodic oxygen reduction reaction(ORR) has a major impact on the performance of PEMFCs,and although platinum(Pt) can accelerate the reaction rate of the ORR,the scarcity and high cost of Pt resources still limit the development of PEMFCs.Therefore,the development of low-cost high-performance ORR catalysts is essential for the commercial application and development of PEMFCs.This paper reviews the research progress of researchers on Pt-based ORR catalysts in recent years,including Pt/C catalysts,Pt-based alloy catalysts,Pt-based intermetallic compounds,and Pt-based single-atom catalysts(SACs),with a focus on Pt-based alloy catalysts with different nanostructures.We described in detail the difficulties and solutions in the research process of various ORR catalysts and explained the principle of their activity enhancement with density functional theory(DFT).In addition,an outlook on the development of Pt-based catalysts is given,and reducing the amount of Pt used and improving the performance of catalysts are the directions to work on in the coming period.

关键词： Pt-based catalysts PEMFCs Pt-based intermetallic compounds Single-atom catalysts

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Graphene binding on black phosphorus enables high on/off ratios and mobility

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National Science Review 2024年第2期11卷 188-195页

作者： Fanrong Lin Zhonghan Cao Feiping Xiao Jiawei Liu Jiabin Qiao Minmin Xue Zhili hu Ying Liu huan Lu Zhuhua Zhang Jens Martin Qingjun Tong Wanlin Guo Yanpeng Liu Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Education State Key Laboratory of Mechanics and Control of Mechanical Structures and Institute for Frontier Science Nanjing University of Aeronautics and Astronautics Centre for Advanced 2D Materials National University of Singapore School of Physics and Electronics Hunan University Centre for Quantum Physics Key Laboratory of Advanced Optoelectronic Quantum Architecture and MeasurementSchool of PhysicsBeijing Institute of Technology Leibniz Institute für Kristallzüchtung

Graphene is one of the most promising candidates for integrated circuits due to its robustness against short-channel effects, inherent high carrier mobility and desired gapless nature for Ohmic contact, but it is difficult to achieve satisfactory on/off ratios even at the expense of its carrier mobility, limiting its device applications. Here, we present a strategy to realize high back-gate switching ratios in a graphene monolayer with well-maintained high mobility by forming a vertical heterostructure with a black phosphorus multi-layer. By local current annealing, strain is introduced within an established area of the graphene, which forms a reflective interface with the rest of the strain-free area and thus generates a robust off-state via local current depletion. Applying a positive back-gate voltage to the heterostructure can keep the black phosphorus insulating, while a negative back-gate voltage changes the black phosphorus to be conductive because of hole accumulation. Then, a parallel channel is activated within the strain-free graphene area by edge-contacted electrodes, thereby largely inheriting the intrinsic carrier mobility of graphene in the on-state. As a result, the device can provide an on/off voltage ratio of >10～3 as well as a mobility of ～8000 cm2V-1s-1at room temperature, meeting the low-power criterion suggested by the International Roadmap for Devices and Systems.

关键词： graphene on/offratio mobility black phosphorus reflective interface

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