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Grassland-type ecosystem stability in China differs under the influence of drought and wet events

Journal of Arid Land 2024年第5期16卷 615-631页

作者： cao Wenyu BAI Jianjun YU Leshan School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China International Business School Shaanxi Normal UniversityXi'an 710119China

Ecological stability is a core issue in ecological research and holds significant implications forhumanity. The increased frequency and intensity of drought and wet climate events resulting from climatechange pose a major threat to global ecological stability. Variations in stability among different ecosystemshave been confirmed, but it remains unclear whether there are differences in stability within the sameterrestrial vegetation ecosystem under the influence of climate events in different directions and ***'s grassland ecosystem includes most grassland types and is a good choice for studying this *** study used the Standardized Precipitation Evapotranspiration Index-12 (SPEI-12) to identify thedirections and intensities of different types of climate events, and based on Normalized DifferenceVegetation Index (NDVI), calculated the resistance and resilience of different grassland types for 30consecutive years from 1990 to 2019 (resistance and resilience are important indicators to measurestability). Based on a traditional regression model, standardized methods were integrated to analyze theimpacts of the intensity and duration of drought and wet events on vegetation stability. The resultsshowed that meadow steppe exhibited the highest stability, while alpine steppe and desert steppe had thelowest overall stability. The stability of typical steppe, alpine meadow, temperate meadow was at anintermediate level. Regarding the impact of the duration and intensity of climate events on vegetationecosystem stability for the same grassland type, the resilience of desert steppe during drought was mainlyaffected by the duration. In contrast, the impact of intensity was not significant. However, alpine steppewas mainly affected by intensity in wet environments, and duration had no significant impact. Ourconclusions can provide decision support for the future grassland ecosystem governance.

关键词： grassland ecosystem stability resistance resilience different climate types drought climate event wet climate event

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A Support Data-Based Core-Set Selection Method for Signal Recognition

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China Communications 2024年第4期21卷 151-162页

作者： Yang Ying Zhu Lidong cao Changjie National Key Laboratory of Wireless Communications(University of Electronic Science and Technology of China) Chengdu 611731China College of Computer Science and Cyber Security(Chengdu University of Technology) Chengdu 610059China College of Mathmatics and Physics(Chengdu University of Technology) Chengdu 610059China

In recent years,deep learning-based signal recognition technology has gained attention and emerged as an important approach for safeguarding the electromagnetic ***,training deep learning-based classifiers on large signal datasets with redundant samples requires significant memory and high *** paper proposes a support databased core-set selection method(SD)for signal recognition,aiming to screen a representative subset that approximates the large signal ***,this subset can be identified by employing the labeled information during the early stages of model training,as some training samples are labeled as supporting data *** support data is crucial for model training and can be found using a border sample *** results demonstrate that the SD method minimizes the impact on model recognition performance while reducing the dataset size,and outperforms five other state-of-the-art core-set selection methods when the fraction of training sample kept is less than or equal to 0.3 on the RML2016.04C dataset or 0.5 on the RML22 *** SD method is particularly helpful for signal recognition tasks with limited memory and computing resources.

关键词： core-set selection deep learning model training signal recognition support data

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Dynamic impact properties of deep sandstone under thermal-hydraulicmechanical coupling loads

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Journal of Mountain Science 2024年第6期21卷 2113-2129页

作者： cao Chunhui DING Haonan ZOU Baoping School of Civil Engineering and Architecture Zhejiang University of Science and TechnologyHangzhou 310023China Zhejiang-Singapore Joint Laboratory for Urban Renewal and Future City Hangzhou 310023China

The deep rock mass within coal mines situated in a challenging environment are characterized by high ground stress,high geotemperature,high osmotic water pressure,and dynamic disturbances from mechanical *** investigate the impact of this complex mechanical environment on the dynamic characteristics of roof sandstone in self-formed roadways without coal pillars,standard specimens of deep sandstone from the 2611 upper tunnel working face of the Yongmei Company within the Henan Coal Chemical Industry Group in Henan,China were prepared,and an orthogonal test was *** a self-developed geotechnical dynamic impact mechanics test system,triaxial dynamic impact tests under thermal-hydraulicmechanical coupling conditions were conducted on deep *** results indicate that under high confining pressure,deep sandstone exhibits pronounced brittle failure at low temperatures,with peak strength gradually decreasing as temperature and osmotic water pressure ***,under low confining pressure and low temperature,the brittleness of deep sandstone weakens gradually,while ductility ***,sandstone demonstrates higher peak strength at low temperatures under high axial pressure conditions,lower peak strength at high temperatures,and greater strain under low axial pressure and high osmotic water *** in impact air pressure and osmotic water pressure have proportionally greater effects on peak stress and peak *** 50%of the input strain energy is utilized as effective energy driving the sandstone fracture *** analysis identifies the optimal combination of factors affecting the peak stress and peak strain of *** the coupling effect,intergranular and transgranular fractures occur within the *** images illustrate that the damage forms range from minor damage with multiple fissures to extensive fractures and severe *** study elucidates the varied dynamic impact me

关键词： Deep sandstone Thermal-hydraulicmechanical coupling Dynamic impact Stress-strain Failure Modes Polar analysis

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Effect of artificial natural light on the development of myopia among primary school-age children in China:a three-year longitudinal study

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 924-931页

作者： Hui-Min Cai meng-Yan Li Yi cao Yu-Lin Wu Ming Liang Yu-Shi Chen Bi-Kun Xian Yu-Juan Huang Xiang-Bin Kong Department of Ophthalmology the Second People’s Hospital of FoshanAffiliated Foshan Hospital of Southern Medical UniversityFoshan 528000Guangdong ProvinceChina Guangdong Medical University Zhanjiang 524023Guangdong ProvinceChina Guangdong Cosio Lighting Corporation Foshan 528000Guangdong ProvinceChina

AIM:To assess the efficacy of artificial natural light in preventing incident myopia in primary school-age ***:This is a prospective,randomized control,intervention study.A total of 1840 students from 39 classes in 4 primary schools in Foshan participated in this *** whole randomization method was adopted to include classes as a group according to 1:1 randomized *** in the control group were illuminated by usual light,and classrooms in the intervention group were illuminated by artificial natural *** students received uncorrected visual acuity and best-corrected visual acuity measurement,non-cycloplegic autorefraction,ocular biometric examination,slit lamp and strabismus ***-year follow-up,the students underwent same *** was defined as spherical equivalent refraction≤-0.50 D and uncorrected visual acuity<20/***:There were 894 students in the control group and 946 students in the intervention group with a mean±SD age of 7.50±*** three-year cumulative incidence rate of myopia was 26.4%(207 incident cases among 784 eligible participants at baseline)in the control group and 21.2%(164 incident cases among 774 eligible participants at baseline)in the intervention group[difference of 5.2%(95%CI,3.7%to 10.1%);P=0.035].There was also a significant difference in the three-year change in spherical equivalent refraction for the control group(-0.81 D)compared with the intervention group[-0.63 D;difference of 0.18 D(95%CI,0.08 to 0.28 D);P<0.001].Elongation of axial length was significantly different between in the control group(0.77 mm)and the intervention group[0.72 mm;difference of 0.05 mm(95%CI,0.01 to 0.09 mm);P=0.003].CONCLUSION:Artificial natural light in the classroom of primary schools can result in reducing incidence rate of myopia during a period of three years.

关键词： myopia artificial natural light school-age children efficacy

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Ternary-phase layered cathodes toward ultra-stable and highrate sodium ion storage

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Rare Metals 2024年第4期43卷 1589-1598页

作者： Wen-Ji Yin Pei-Dan Su Qi Lu Xiao-Qiong Li Ji-Ming Peng Teng-Fei Zhou Ge-meng Liang Yu-Liang cao Hong-Qiang Wang Qing-Yu Li Si-Jiang Hu Guangxi Key Laboratory of Low Carbon Energy Materials School of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin541004China Institutes of Physical Science and Information Technology Anhui UniversityHefei230601China Department of Chemistry and Pharmaceutical Sciences Guilin Normal CollegeGuilin541199China College of Chemistry and Chemical Engineering Huanggang Normal UniversityHuanggang438000China School of Chemical Engineering and Advanced Materials The University of AdelaideAdelaide5005Australia Engineering Research Center of Organosilicon Compounds and Materials of Ministry of Education College of Chemistry and Molecular SciencesWuhan UniversityWuhan430072China

With the shortage of lithium resources,sodiumion batteries(SIBs)are considered one of the most promising candidates for lithium-ion batteries.P2-type and O3-type layered oxides are one of the few cathodes that can access high energy ***,they usually exhibit structural change,capacity decay,and slow Na ion ***,we present layered ternary-phase cathodes with P2,P3 and O3 phases by a lattice doping strategy,which is demonstrated by X-ray diffraction(XRD)*** the characteristics of P2,P3 and O3 phases,the layered composites show performance improvement during long-term battery *** particular,Na_(0.7)Li_(0.1)Co_(0.3-)Fe_(0.3)Mn_(0.3)O_(2)(NLCFM)delivers a reversible capacity of120.1 mAh·g^(-1)at 0.1C(1.0C=175 mA·g^(-1))with a superior capacity retention of 72.5%after 1000 cycles *** work offers insights into the development of advanced cathode materials for SIBs.

关键词： Sodium-ion battery Cathode material Layered oxides Lattice doping Mixed phase

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Impacts of pancreatic exocrine insufficiency on gut microbiota

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第4期25卷 271-279页

作者： Yulin GUO Feng cao Fei LI Department of General Surgery Xuanwu Hospital of Capital Medical UniversityBeijing 100053China Acute Pancreatitis Clinical Center of Capital Medical University Beijing 100053China

Pancreatic exocrine insufficiency(PEI)can be induced by various kinds of diseases,including chronic pancreatitis,acute pancreatitis,and *** main pathogenetic mechanism of PEI involves the decline of trypsin synthesis,disorder of pancreatic fluid flow,and imbalance of secretion *** studies have shown that PEI could induce gut bacterial overgrowth and dysbiosis,with the abundance of Lactobacillus and Bifidobacterium increasing the most,which could be partially reversed by pancreatic enzyme replacement *** studies have also confirmed the association between PEI and the dysbiosis of gut *** exocrine secretions and changes in duodenal p H as well as bile salt malabsorption brought about by PEI may affect and shape the abundance and composition of gut *** turn,the gut microbiota may impact the pancreatic exocrine acinus through potential bidirectional *** forward,more and higher-quality studies are needed that focus on the mechanism underlying the impact of PEI on the gut microbiota.

关键词： Pancreatic exocrine insufficiency Gut microbiota Gut microbiome Pancreatic enzyme replacement therapy

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Taphonomy and Paleoecology of Lycoptera: A Case Study from the Lower Jehol Group in Western Liaoning, Northeastern China

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Journal of Earth Science 2024年第3期35卷 737-746页

作者： Zhongwu Lan Rong cao Shujing Zhang State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430078China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Geology Trinity CollegeDublin 999015Ireland

Taphonomy and paleoecology(biological behavior)of the Early Cretaceous fish fossils are poorly *** study reports for the first time a detailed taphonomical and paleoecological study on Lycoptera in the Mesozoic strata of western Liaoning Province,NE *** XRD analysis shows that gismondine is the dominant clay minerals that could have contributed to the preservation of Lycoptera fossils and microbial mat fragments in the fossil-bearing *** may have formed under volcanism-related hydrothermal regime that was transformed from crystal and lithic ***μ-XRF imaging analysis shows a dominant chemical composition of Al,Si,P,S,Rh,K,Ca,Ti,C,Cr,Mn,Fe,Ni,among which P,Ca,C and S are enriched in the fish skeleton in comparison to the *** suggests a dominant apatite composition for the fish *** influence did not smear off these organic signals probably because of protection of *** coexistance of C and S with Ni is assumed to represent recovered primary productivity following volcanic explosions and toxic gas *** head of juvenile fish stays close to the body of adult *** further discoveries,such phenomenon is interpreted to suggest that adult fish actively protected juvenile fish in the presence of environmental pressures such as anoxia and deterioration of water quality induced by *** acidification and hypoxia in association with volcanism created a harmful environment causing mass extinction of *** adult Lycoptera protected their juveniles by its body at the moment before *** biological behavior will be increasingly reported given the wide occurrence of Lycoptera in Mesozoic strata.

关键词： Lycoptera taphonomy paleoecology fish Jehol Group NE China.

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Enzymatic C1 reduction using hydrogen in cofactor regeneration

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Frontiers of Chemical Science and Engineering 2024年第7期18卷 33-40页

作者： Ruishuang Sun Chenqi cao Qingyun Wang Hui cao Ulrich Schwaneberg Yu Ji Luo Liu Haijun Xu Beijing Bioprocess Key Laboratory Beijing University of Chemical TechnologyBeijing 100029China Institute of Biotechnology Rheinisch-Westfälische Technische Hochschale(RWTH)AachenAachen 52074Germany

Carbon dioxide fixation presents a potential solution for mitigating the greenhouse gas *** carbon dioxide fixation,C1 compound reduction requires a high energy *** calculations suggest that the energy source for cofactor regeneration plays a vital role in the effective enzymatic C1 *** utilizes renewable hydrogen to achieve the regeneration and supply cofactor nicotinamide adenine dinucleotide(NADH),providing a driving force for the reduction reaction to reduce the thermodynamic barrier of the reaction cascade,and making the forward reduction pathway thermodynamically *** on the regeneration of cofactor NADH by hydrogenase,and coupled with formaldehyde dehydrogenase and formolase,a favorable thermodynamic mode of the C1 reduction pathway for reducing formate to dihydroxyacetone(DHA)was designed and *** resulted in accumulation of 373.19μmol·L^(-1) DHA after 2 h,and conversion reaching 7.47%.These results indicate that enzymatic utilization of hydrogen as the electron donor to regenerate NADH is of great significance to the sustainable and green development of bio-manufacturing because of its high economic efficiency,no by-products,and environment-friendly ***,formolase efficiently and selectively fixed the intermediate formaldehyde(FALD)to DHA,thermodynamically pulled formate to efficiently reduce to DHA,and finally stored the low-grade renewable energy into chemical energy with high energy density.

关键词： [NiFe]-hydrogenase SH formolase NADH regeneration C1 compound reduction thermodynamic calculation

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基于PSA的中压电力线载波通信自适应阻抗匹配

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电力系统保护与控制 2024年第18期52卷 45-52页

作者：谢志远曹通华北电力大学电气与电子工程学院河北保定071003

在中压电力线通信中,针对复杂电器元件的种类、数量不断变化等因素导致线路阻抗不匹配而影响通信质量的问题,提出了一种中压电力线载波通信自适应阻抗匹配方法。首先,建立了中压阻抗匹配系统模型,在该模型的基础上提出了一种π型自适应... 详细信息

在中压电力线通信中,针对复杂电器元件的种类、数量不断变化等因素导致线路阻抗不匹配而影响通信质量的问题,提出了一种中压电力线载波通信自适应阻抗匹配方法。首先,建立了中压阻抗匹配系统模型,在该模型的基础上提出了一种π型自适应阻抗匹配电路。然后,根据该电路设计了符合阻抗共轭匹配原理的目标函数,通过PID搜索算法(PID-based search algorithm, PSA)寻找最优元件参数,实现目标函数最优。最后,在此模型基础上仿真分析了PSA算法、粒子群算法(particle swarm optimization, PSO)和遗传算法(genetic algorithm, GA)的优劣性。结果表明,PSA算法在收敛速度和寻优精度方面优于PSO和GA算法,能够有效实现阻抗匹配进而改善载波通信质量,为中压电力线通信进一步研究提供了可行性方案。

关键词：中压电力线通信阻抗匹配 PSA 自适应

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Integrated ribosome and proteome analyses reveal insights into sevoflurane-induced long-term social behavior and cognitive dysfunctions through ADNP inhibition in neonatal mice

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Zoological Research 2024年第3期45卷 663-678页

作者： Li-Rong Liang Bing Liu Shu-Hui cao You-Yi Zhao Tian Zeng Mei-Ting Zhai Ze Fan Dan-Yi He San-Xin Ma Xiao-tong Shi Yao Zhang Hui Zhang State Key Laboratory of Oral&Maxillofacial Reconstruction and Regeneration National Clinical Research Center for Oral DiseasesShaanxi Engineering Research Center for Dental Materials and Advanced ManufactureDepartment of AnesthesiologySchool of StomatologyAir Force Medical UniversityXi’anShaanxi 710032China Department of Anesthesiology 986th Air Force HospitalAir Force Medical UniversityXi’anShaanxi 710032China

A growing number of studies have demonstrated that repeated exposure to sevoflurane during development results in persistent social abnormalities and cognitive ***,an active fragment of the activity-dependent neuroprotective protein(ADNP),has been implicated in social and cognitive ***,the potential of davunetide to attenuate social deficits following sevoflurane exposure and the underlying developmental mechanisms remain poorly *** this study,ribosome and proteome profiles were analyzed to investigate the molecular basis of sevoflurane-induced social deficits in neonatal *** neuropathological basis was also explored using Golgi staining,morphological analysis,western blotting,electrophysiological analysis,and behavioral *** indicated that ADNP was significantly down-regulated following developmental exposure to *** adulthood,anterior cingulate cortex(ACC)neurons exposed to sevoflurane exhibited a decrease in dendrite number,total dendrite length,and spine ***,the expression levels of Homer,PSD95,synaptophysin,and vglut2 were significantly reduced in the sevoflurane ***-clamp recordings indicated reductions in both the frequency and amplitude of miniature excitatory postsynaptic currents(mEPSCs).Notably,davunetide significantly ameliorated the synaptic defects,social behavior deficits,and cognitive impairments induced by *** analysis revealed that loss of ADNP led to dysregulation of Ca^(2+)activity via the Wnt/β-catenin signaling,resulting in decreased expression of synaptic *** of Wnt signaling was restored in the davunetide-treated ***,ADNP was identified as a promising therapeutic target for the prevention and treatment of neurodevelopmental toxicity caused by general *** study provides important insights into the mechanisms underlying social and cognitive disturbances caused by sevoflurane exposure in neonatal

关键词： Davunetide Sevoflurane Abnormal social behaviors ADNP Neurotoxicity

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