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Effects of different concentrations of nicotinamide on hematopoietic stem cells cultured in vitro

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World Journal of Stem Cells 2024年第2期16卷 163-175页

作者： Yan Ren Yan-ni Cui Hong-Wei Wang The Second Clinical Medical College Shanxi Medical UniversityTaiyuan 030001Shanxi ProvinceChina Department of Hematology The Second Hospital of Shanxi Medical UniversityTaiyuan 030001Shanxi ProvinceChina Department of Hematology Key Laboratory of Molecular Diagnosis and Treatment of Blood Diseases in Shanxi ProvinceTaiyuan 030001Shanxi ProvinceChina

BACKGROUND In vitro expansion to increase numbers of hematopoietic stem cells(HSCs)in cord blood could improve clinical efficacy of this vital ***(NAM)can promote HSC expansion ex vivo,but its effect on hematopoietic stem and progenitor cells(HSPCs,CD34^(+)CD38)and functional subtypes of HSCs-shortterm repopulating HSCs(ST-HSCs,CD34^(+)CD38CD45RACD49f^(+))and long-term repopulating HSCs(LT-HSCs,CD34^(+)CD38CD45RACD49f^(+)CD90^(+))is not yet *** a sirtuin 1(SIRT1)inhibitor,NAM participates in regulating cell adhesion,polarity,migration,proliferation,and ***,SIRT1 exhibits dual effects by promoting or inhibiting differentiation in different tissues or *** propose that the concentration of NAM may influence proliferation,differentiation,and SIRT1 signaling of *** To evaluate the effects and underlying mechanisms of action of different concentrations of NAM on HSC proliferation and *** CD34^(+)cells were purified from umbilical cord blood using MacsCD34 beads,and cultured for 10-12 d in a serum-free medium supplemented with cytokines,with different concentrations of NAM added according to experimental *** cytometry was used to detect phenotype,cell cycle distribution,and apoptosis of the cultured ***-time polymerase chain reaction was used to detect the transcription levels of target genes encoding stemness-related factors,che mokines,components of hypoxia pathways,and antioxidant ***-dihydro-fluorescein diacetate probes were used to evaluate intracellular production of reactive oxygen species(ROS).Determination of the effect of different culture conditions on the balance of cytokine by cytometric bead *** Compared with the control group,the proportion and expansion folds of HSPCs(CD34^(+)CD38)incubated with 5 mmol/L or 10 mmol/L NAM were significantly increased(all Pnificantly

关键词： Hematopoietic stem cells nicotinamide Concentration Proliferation Differentiation Sirtuin 1

Decline in tree-ring growth of Picea mongolica and its intra-annual eco-physiological responses to drought and CO_(2) enrichment in semi-arid China

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Journal of Forestry Research 2024年第4期35卷 89-101页

作者： Xiaomin Zeng Ping ni Xiaohong Liu Wenzhi Wang Yao Li Wenchao Wang School of Geography and Tourism Shaanxi Normal UniversityXi’an 710119People’s Republic of China The Key Laboratory of Mountain Environment Evolution and Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041People’s Republic of China CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Episodes of drought-induced decline in tree growth and mortality are becoming more frequent as a result of climate warming and enhanced water stress in semi-arid ***,the ecophysiological mechanisms under-lying the impact of drought on tree growth remains *** this study,earlywood and latewood tree-ring growth,δ^(13)C,andδ^(18)O chronologies of Picea mongolica from 1900 to 2013 were developed to clarify the intra-and inter-annual tree-ring growth responses to increasingly fre-quent *** results indicate that annual basal area increment residuals(BAI_(res)),which removed tree age and size effects,have significantly decreased since ***-ever,the decreasing trend of earlywood BAI_(res) was higher than that of *** response analysis suggests that the dominant parameters for earlywood and latewood proxies(BAI_(res),δ^(13)C andδ^(18)O)were drought-related climate variables(Palmer drought severity index,temperature,rela-tive humidity,and vapor pressure deficit).The most signifi-cant period of earlywood and latewood proxies’responses to climate variables were focused on June-July and July-August,***_(res),andδ^(13)C were significantly affected by temperature and moisture conditions,whereasδ^(18)O was slightly *** stomatal conduct-ance due to drought outweighed the influence of increasing CO_(2) on intrinsic water use efficiency(iWUE),and ultimately led to a decline in BAI_(res).Compared to latewood,the faster decreasing BAI_(res) and smaller increasing iWUE of early-wood suggested trees were more vulnerable to water stress in the early growing *** study provides insights into the inter-and intra-annual mechanisms of tree-ring growth in semi-arid regions under rising CO_(2) and climate change.

关键词： Tree growth Drought Water-use efficiency Seasonal differences Stable isotopes

Response mechanism of soil microorganisms to simulated precipitation in the source wetland of Qinghai Lake

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Ecological Processes 2024年第2期13卷 61-71页

作者： Xinye Wang ni Zhang Kelong Chen Tiexi Chen Desheng Qi Yuanxi Ma School of Geographical Sciences Qinghai Normal University National Positioning Observation and Research Station of Qinghai Lake Wetland Ecosystem in Qinghai National Forestry and Grassland Administration Key Laboratory of Tibetan Plateau Land Surface Processes and Ecological Conservation(Ministry of Education) Qinghai Normal University School of Geographical Sciences Nanjing University of Information Science and Technology Qinghai Provincial land spatial Planning Research Institute

Background Changes in precipitation patterns crucially impact soil microbial communities, and the ecosystem in Qinghai-Tibet Plateau(QTP) is highly vulnerable to climate change. However, we do not fully understand how soil microbial communities in the source wetlands of QTP respond to changes in precipitation. In this study, we employed advanced techniques such as high-throughput sequencing and metabolomics to investigate how soil microbial communities in a source wetland of Qinghai Lake respond to changes in precipitation after quadrennial precipitation *** Our findings showed that the predominant microbiota in the source wetland was Proteobacteria. Interestingly, alterations in precipitation levels, whether increased or reduced, did not significantly impact the diversity or functional groups of the microbial community. However, the structure of the microbial community did respond notably to changes in precipitation, leading to shifts in the relative abundance of Spirochaetes and Treponema. A notable finding was that reduced precipitation levels(– 25% and-50%) and mild increases in precipitation(25%) within the region contributed to increased soil carbon content. However, this effect ceased to manifest when precipitation increased by 50%. Additionally, the reduction in precipitation prompted the release of soil metabolites like syringic acid and aldosterone, while enhanced precipitation resulted in a decrease in aldosterone *** Precipitation changes altered the relative abundance of soil microbial communities and metabolites, which was conducive to increasing carbon storage in this alpine wetland.

关键词： Qinghai-Tibet Plateau Climate change Precipitation gradient Carbon and nitrogen cycles LC/MS

Effects of weaning on intestinal longitudinal muscle-myenteric plexus function in piglets

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Science China(Life Sciences) 2024年第2期67卷 379-390页

作者： Jing Li Fenfen Liu Kaibin Mo Hengjia ni Yulong Yin Key Laboratory of Agro-Ecological Processes in Subtropical Region Hunan Provincial Key Laboratory of Animal Nutritional Physiology and Metabolic ProcessHunan Research Center of Livestock and Poultry SciencesSouth Central Experimental Station of Animal Nutrition and Feed Science in the Ministry of AgricultureInstitute of Subtropical AgricultureChinese Academy of SciencesChangsha 410125China University of Chinese Academy of Sciences Beijing 100008China Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation College of Veterinary MedicineSouth China Agricultural UniversityGuangzhou 510642China

Weaning piglets usually suffer from severe diarrhea(commonly known as postweaning diarrhea,PWD)along with intestinal motility *** peristalsis is mainly regulated by the longitudinal muscle-myenteric plexus(LM-MP).To understand the relationship between intestinal LM-MP function and the development of PWD,we compared the intestinal electrical activity,and the transcriptional profile of the LM-MP between 21-day-old piglets(just weaned,n=7)and 24-day-old piglets(suffered the most severe weaning stress,n=7).The results showed that 24-day-old piglets exhibited different degrees of diarrhea.A significant increase in the slow-wave frequency in the ileum and colon was observed in 24-day-old piglets,while c-kit expression in the intestinal LM-MPs was significantly decreased,indicating that PWD caused by elevated slow-wave frequency may be associated with loss of *** real-time quantitative PCR(RT-q PCR)and enzyme-linked immunosorbent assay(ELISA)showed that intestinal LM-MPs in 24-day-old piglets may undergo inflammation and oxidative *** increases in 8-hydroxy-2′-deoxyguanosine and decreases in thioredoxin suggest that weaning may lead to DNA damage in the LM-MP of 24-day-old *** addition,activating transcription factor 3 was significantly upregulated,indicating nerve damage in the LM-MP of 24-day-old *** transcriptomic results showed that most of the differentially expressed genes in the ileal LM-MP after weaning were downregulated and closely related to the cell cycle *** RT-q PCR analysis showed that the relative expression of p21 was upregulated,while the expression of cyclin A2,cyclin B1,and proliferating cell nuclear antigen was downregulated in the ileal and colonic LM-MP of 24-day-old piglets,suggesting that weaning may inhibit cell proliferation and cause G1/S cell cycle arrest in ileal and colonic *** conclusion,weaning may lead to cell cycle arrest by causing DNA damage in the LM-MP,impairing i

关键词： weaning piglets diarrhea longitudinal muscle-myenteric plexus

Semitransparent organic solar cells with high light utilization efficiency and color rendering index

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Science China Chemistry 2024年第7期67卷 2248-2256页

作者： ni Gao Haijun Bin Shangrong Wu RenéA.J.Janssen Yongfang Li Laboratory of Advanced Optoelectronic Materials Suzhou Key Laboratory of Novel Semiconductor Materials and DevicesCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China Jiangsu Key Laboratory of Advanced Negative Carbon Technologies Soochow UniversitySuzhou 215123China Molecular Materials and Nanosystems&Institute for Complex Molecular Systems Eindhoven University of TechnologyEindhoven 5600 MBthe Netherlands

Semitransparent organic solar cells(ST-OSCs)have garnered considerable attention as promising renewable energy technology for integrating photovoltaics into ***,there is a trade-off between power conversion efficiency(PCE)and average visible transmittance(AVT),which hinders the achievement of a high light utilization efficiency(LUE).In this study,we propose a valuable method to address this challenge by replacing the transparent top electrode,Ag,with a 20 nm layer of *** ST-OSCs based on the 20 nm Au electrode demonstrate superior exciton extraction,more efficient charge collection,and higher color-rendering index(CRI)due to their smoother surface,higher conductivity,and enhanced visible light transmittance,resulting in a significantly higher PCE of 13.67%and an enhanced AVT of 30.17%,contributing to a high LUE of 4.15%.Additionally,optically transparent dielectric layers,applied on the front and back sides of the ST-OSCs to further boost performance,delivered an impressive LUE of 4.93%,with PCE and AVT values reaching 14.44%and 34.12%,***,the champion ST-OSCs also exhibited a favorable CRI value of *** achievements represent the bestperforming ST-OSCs to date with both high LUE and CRI and hold significant implications for the prospective commercialization of ST-OSCs.

关键词： semitransparent organic solar cells power conversion efficiency average visible transmittance light utilization efficiency color-rendering index

Improved Particle Swarm Optimization for Parameter Identification of Permanent Magnet Synchronous Motor

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Computers, Materials & Continua 2024年第5期79卷 2187-2207页

作者： Shuai Zhou Dazhi Wang Yongliang ni Keling Song Yanming Li School of Information Science and Engineering Northeastern UniversityShenyang110819China China Northern Vehicle Research Institute Beijing100072China

In the process of identifying parameters for a permanent magnet synchronous motor,the particle swarm optimization method is prone to being stuck in local optima in the later stages of iteration,resulting in low parameter *** work proposes a fuzzy particle swarm optimization approach based on the transformation function and the filled *** approach addresses the topic of particle swarmoptimization in parameter identification from two ***,the algorithm uses a transformation function to change the form of the fitness function without changing the position of the extreme point of the fitness function,making the extreme point of the fitness function more prominent and improving the algorithm’s search ability while reducing the algorithm’s computational ***,on the basis of themulti-loop fuzzy control systembased onmultiplemembership functions,it is merged with the filled function to improve the algorithm’s capacity to skip out of the local optimal *** approach can be used to identify the parameters of permanent magnet synchronous motors by sampling only the stator current,voltage,and speed *** simulation results show that the method can effectively identify the electrical parameters of a permanent magnet synchronous motor,and it has superior global convergence performance and robustness.

关键词： Transformation function filled function fuzzy particle swarm optimization algorithm permanent magnet synchronous motor parameter identification

Memory Trace for Fear Extinction:Fragile yet Reinforceable

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Neuroscience Bulletin 2024年第6期40卷 777-794页

作者： Ying Liu Shuai Ye Xin-ni Li Wei-Guang Li Department of Rehabilitation Medicine State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain ScienceHuashan HospitalInstitute for Translational Brain ResearchFudan UniversityShanghai200032China

Fear extinction is a biological process in which learned fear behavior diminishes without anticipated reinforcement,allowing the organism to re-adapt to ever-changing *** on the behavioral hypothesis that extinction is new learning and forms an extinction memory,this new memory is more readily forgettable than the original fear *** brain’s cellular and synaptic traces underpinning this inherently fragile yet reinforceable extinction memory remain *** questions are about the whereabouts of the engram neurons that emerged during extinction learning and how they constitute a dynamically evolving functional construct that works in concert to store and express the extinction *** this review,we discuss recent advances in the engram circuits and their neural connectivity plasticity for fear extinction,aiming to establish a conceptual framework for understanding the dynamic competition between fear and extinction memories in adaptive control of conditioned fear responses.

关键词： Fear extinction memory Memory trace Fear relapse Medial prefrontal cortex Basolateral amygdala Ventral hippocampus Insular cortex Synaptic adaptations

Spatial-temporal variations of surface water area during 1986-2018 in Qinghai Province,northwestern China based on Google Earth Engine

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Big Earth Data 2024年第2期8卷 333-349页

作者： Luying Zhu Haifeng Tian ni Huang Li Wang Zheng niu State Key Laboratory of Remote Sensing Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingChina College of Resources and Environment University of Chinese Academy of SciencesBeijingChina College of Geography and Environmental Science Henan UniversityKaifengChina

Called the“Water Tower”,the water resource in Qinghai Province plays a vital role in the ecological environment of northwestern ***,significant uncertainty exists regarding its spatialtemporal *** this study,the data on the surface water of Qinghai Province from 1986 to 2018 was extracted and a systemic analysis of its spatial-temporal variations and responses to climate change was conducted using the Google Earth Engine(GEE)cloud processing *** findings revealed that the surface water in Qinghai Province was primarily concentrated in the Qaidam Basin,the Hoh Xil Nature Reserve,and Qinghai *** surface water area in Qinghai Province exhibited an overall increasing trend,with the temperature and precipitation being the primary drivers of this *** results provide crucial insights into the variations of surface water variations in Qinghai Province,northwestern China,under the influence of climate change.

关键词： Qinghai Province Google Earth Engine surface water climate change

Cucurbit[8]uril-regulated face-to-face dimerization assembly enhanced photosensitization and photocatalysis

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Science China Chemistry 2024年第5期67卷 1605-1612页

作者： Haigen nie Die Hu Zhiyao Zeng Yan Fan Yaxin Zhai Xin-Long ni Key Laboratory of Chemical Biology and Traditional Chinese Medicine Ministry of Educational of ChinaKey Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan ProvinceCollege of Chemistry and Chemical EngineeringHunan Normal UniversityChangsha 410081China Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Department of PhysicsHunan Normal UniversityChangsha 410081China

In water, N,N′-diarylpyridinium thiazolo[5,4-d]thiazole guests(G1–G3) were encapsulated by cucurbit[8]uril(Q[8]) to construct Q[8]_(3)/G_(2) complexes, in which the encapsulated G molecules exist as an exact face-to-face dimer. These complexation behaviors have been indicated by proton nuclear magnetic resonance(~1H NMR) spectroscopy and isothermal titration calorimetry(ITC),and have been confirmed by X-ray single crystal structural analysis of Q[8]_(3)/G2_(2). While free guests G1–G3 have no ability to sensitize singlet oxygen, they all become effective singlet oxygen sensitizers when complexed with Q[8]. By irradiation of white light, Q[8]_(3)/G_(2) complexes induced selective oxidation of aryl sulfide to aryl sulfoxide in good yields and selective oxidation of dimethyl sulfide(DMS) to dimethyl sulfoxide(DMSO) in excellent yields without over-oxidation to dimethyl sulfone(DMSO_(2))even for elongated irradiation. High-yield photo-oxidation of DMS to DMSO_(2) was only achieved by irradiation of blue light in the presence of Q[8]_(3)/G1_(2), which was also effective in photobleaching of Rhodamine B in water. The higher photo-oxidation power of Q[8]_(3)/G1_(2) has been ascribed to an additional generation of reactive oxygen species besides singlet oxygen.

关键词： host-guest interaction dimerization macrocycles photosensitization