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Dynamics of the spatiotemporal velocity of glaciers on the eastern slope of Mount Gongga,China,under climate change

Advances in Climate Change Research 2024年第3期15卷 490-499页

作者： Yin FU Bo zhang Qiao LIU Guo-Xiang LIU Rui zhang Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610299China Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 611756China

The quantitative assessment of glacier flow velocity dynamics plays a pivotal role in understanding its response mechanisms concerning climate *** work provides a systematic quantitative assessment of the deceleration status of glaciers in this region by investigating the motion evolution of typical glaciers in Mount Gongga in recent years,thereby revealing the seasonal dynamics and inter-annual evolution over an extensive time *** used the optical flow-small baseline subset(OF-SBAS)method to compute the time-series velocities of the Hai-luogou Glacier and the Mozigou Glacier using 178 archived Sentinel-1 satellite synthetic aperture radar(SAR)images from 2014 to *** findings revealed a prominent seasonal pattern in glacier motion,characterised by cyclic variations in velocity from cold to warm ***,we identified variations in velocities across distinct regions of the glacier surface,underscored by the lag in the peak time node of glacier flow with increasing *** pattern may have been determined by a combination of internal and external factors,including mass accumulation and ablation-driven subglacial drainage,as well as the glacier geomorphological ***,during 2015-2021,the glaciers on the eastern slope of Mount Gongga exhibited an overarching trend of ***,the ablation area of the Hailuogou Glacier recorded the most substantial deceleration,exceeding 8%per *** study underscores the efficacy of the OF-SBAS method in extracting long-term glacier *** work also establishes a robust foundation for the analysis of spatiotemporal fluctuations in glacier movement within the context of climate warming.

关键词： Monsoonal temperate glaciers Synthetic aperture radar(SAR) Glacier movement Hailuogou glacier Mozigou glacier Optical flow-small baseline subset(OF-SBAS)

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Variations of sediment organic phosphorus and organic carbon during the outbreak and decline of algal blooms in Lake Taihu,China

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Journal of Environmental Sciences 2024年第5期139卷 34-45页

作者： Jiehua Wang Xiuling Bai Wenchao Li Pingping zhang Mengdi zhang Haoran Wang Yingge Bai College of Geography and Environmental Science Henan UniversityKaifeng 475004China Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions(Henan University) Ministry of EducationKaifeng 475004China National Demonstration Center for Environment and Planning Henan UniversityKaifeng 475004China Surrey International Institute Dongbei University of Finance and EconomicsDalian 116000China

In this study,sediment organic phosphorus(OP)and organic carbon(OC)in Lake Taihu,China,as well as their relationships,were analyzed during the outbreak and decline of algal blooms(ABs)over a five-month field *** results showed synchronous temporal changes in the sediment OP and OC contents with the development of *** addition,there was a significant positive correlation between the sediment OP and OC(pmay also depend on the scale of the ABs *** obtained results revealed significant differences in the sediment OC and OP contents between the months(p<0.05).In addition,OP in the sediments was dominated by orthophosphate diester(phospholipids and DNA-P)and orthophosphate monoester during the ABs outbreak and decline,*** active OC contents and proportions in the sediments in the ABs outbreak were significantly lower than those observed in the ABs decline period,demonstrating the significant impacts of the ABs outbreak and decline on the sediment OC and OP in Lake Taihu.

关键词： Algal blooms Organic phosphorus Organic carbon Sediment ^(31)P NMR Lake Taihu

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STGNN-LMR:A Spatial–Temporal Graph Neural Network Approach Based on sEMG Lower Limb Motion Recognition

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Journal of Bionic Engineering 2024年第1期21卷 256-269页

作者： Weifan Mao Bin Ma Zhao Li Jianxing zhang Yizhou Lu Zhuting Yu Feng zhang Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China University of Chinese Academy of Sciences Beijing 101408China University of Science and Technology of China Hefei 230026China Shanghai Zhongyan Jiuyi Technology Co. Ltd.Shanghai 201821China Academy of Military Science Bejing 100091China

Lower limb motion recognition techniques commonly employ Surface Electromyographic Signal(sEMG)as input and apply a machine learning classifier or Back Propagation Neural Network(BPNN)for ***,this artificial feature engineering technique is not generalizable to similar tasks and is heavily reliant on the researcher’s subject *** contrast,neural networks such as Convolutional Neural Network(CNN)and Long Short-term Memory Neural Network(LSTM)can automatically extract features,providing a more generalized and adaptable approach to lower limb motion *** this approach overcomes the limitations of human feature engineering,it may ignore the potential correlation among the sEMG *** paper proposes a spatial–temporal graph neural network model,STGNN-LMR,designed to address the problem of recognizing lower limb motion from multi-channel ***-LMR transforms multi-channel sEMG into a graph structure and uses graph learning to model spatial–temporal *** 8-channel sEMG dataset is constructed for the experimental stage,and the results show that the STGNN-LMR model achieves a recognition accuracy of 99.71%.Moreover,this paper simulates two unexpected scenarios,including sEMG sensors affected by sweat noise and sudden failure,and evaluates the testing results using hypothesis *** to the experimental results,the STGNN-LMR model exhibits a significant advantage over the control models in noise scenarios and failure *** experimental results confirm the effectiveness of the STGNN-LMR model for addressing the challenges associated with sEMG-based lower limb motion recognition in practical scenarios.

关键词： Lower limb motion recognition Exoskeleton sEMG.Graph neural network Noise Sensor failure

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Hydrogen storage thermodynamics and kinetics of as-cast Ce-Mg-Ni-based alloy

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Journal of Iron and Steel Research International 2024年第3期31卷 752-766页

作者： Yan Qi Xin zhang Jun Li Dong-liang Zhao Shi-hai Guo Yang-huan zhang Department of Functional Material Research Central Iron and Steel Research InstituteBeijing 100081China China Rare Earth New Material(Weishan)Co..Ltd. Jining 277600ShandongChina Collaborative Innovation Center of Integrated Exploitation of Bayan Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010Inner MongoliaChina

The reaction kinetics of alloys based on magnesium are known to be greatly improved by the partial substitution of Mg with rare earths and transition metals,particularly *** enhanced superficial hydrogen dissociation rate,the weakened Mg-H bond and the lower activation energy following element replacement are thought to be related to the better *** experimental alloys Ce5Mg_(95-x)Ni_(x)(x=5,10,15)were smelted by the vacuum induction *** phase transformation and structural evolution of experimental alloys before and after reaction with hydrogen were char-acterized by X-ray diffraction,scanning electron microscopy and transmission electron *** cast specimens contain CeMg_(12),Mg and Mg_(2)Ni phases,and the increase in Ni content results in an obvious growth of Mg_(2)Ni *** isothermal and non-isothermal hydrogenation and dehydrogenation kinetics of the experimental specimens were investi-gated using the Sievert apparatus,differential scanning calorimetry and thermal gravimetric *** activation energy may be calculated using the Arrhenius and Kissinger *** experimental alloys have been shown to have good activation properties,with a reversible hydriding and dehydriding capacities of around 5.0 wt.%in the first *** initial dehydrogenation temperature of MgH_(2) decreases from 557.5 to 537.7 K with changing Ni content from 5 to 15 at.%.The dehydrogenation activation energy also reduces from 77.09 to 62.96 kJ/mol,which explains the improved hydrogen storage performance caused by Ni *** can be shown that the impact of Ni on the decomposition enthalpy of MgH_(2) is quite modest,with the absolute enthalpy(ΔHr)only decreasing from 78.48 to 76.15 kJ/mol.

关键词： Mg-based alloy Ni content Hydrogen storage kinetics Thermodynamic property Activation energy

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Formatted PVDF in lamellar composite solid electrolyte for solidstate lithium metal battery

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Nano Research 2024年第6期17卷 5159-5167页

作者： Xinji zhang Yafang zhang Shiyue Zhou Jingchuan Dang Chenye Wang Wenjia Wu Jingtao Wang School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China

Solid polymer electrolytes(SPEs)hold great application potential for solid-state lithium metal battery because of the excellent interfacial contact and processibility,but being hampered by the poor room-temperature conductivity(~10^(−7)S·cm^(−1))and low lithium-ion transference number(tLi+).Here,a lamellar composite solid electrolyte(Vr-NH_(2)@polyvinylidene fluoride(PVDF)LCSE)withβ-conformation PVDF is fabricated by confining PVDF in the interlayer channel of-NH_(2)modified vermiculite lamellar *** demonstrate that the conformation of PVDF can be manipulated by the nanoconfinement effect and the interaction from channel *** presence of-NH_(2)groups could induce the formation ofβ-conformation PVDF through electrostatic interaction,which serves as continuous and rapid lithium-ion transfer *** a result,a high room-temperature ionic conductivity of 1.77×10^(−4)S·cm^(−1)is achieved,1-2 orders of magnitude higher than most ***,Vr-NH_(2)@PVDF LCSE shows a high tLi+of 0.68 because of the high dielectric constant,~3 times of that of PVDF SPE,and surpassing most of reported *** LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)||Li cell assembled by Vr-NH_(2)@PVDF LCSE obtains a discharge specific capacity of 137.1 mAh·g^(−1)after 150 cycles with a capacity retention rate of 93%at 1 C and 25℃.This study may pave a new avenue for high-performance SPEs.

关键词： solid-state lithium metal battery lamellar composite solid electrolyte β-conformation polyvinylidene fluoride(PVDF) room-temperature ionic conductivity lithium-ion transference number

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Fasn involved in the nephrotoxicity induced by polystyrene nanoplastics and the intervention of melatonin through intestinal microbiota-mediated lipid metabolism disorder

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Nano Research 2024年第8期17卷 7365-7375页

作者： Huiwen Kang Danyang Huang Jiaru Jing Wei zhang Lei zhang Jingyu Wang Ziyan Liu Lin Han Ziyan Wang Lefeng zhang Ai Gao Department of Occupational Health and Environmental Health School of Public HealthCapital Medical UniversityBeijing 100069China Beijing Key Laboratory of Environmental Toxicology Capital Medical UniversityBeijing 100069China

Nanoplastics(NPs)can accumulate in the kidney and cause kidney injury,but the multi-organ interaction mechanism and preventive measures of kidney injury are still *** this study,in vivo(60μg/day,42 days)and in vitro(0.4μg/μL,24 h)exposure models of polystyrene nanoplastics(PS-NPs,80 nm)in mice and human kidney cortex proximal tubule epithelial cells(HK-2 cells)were established,*** study revealed that PS-NPs caused obvious pathological changes and impaired renal function in mice,which were related to lipid metabolism disorders mediated by intestinal ***-fatty acid synthase(Fasn)-docosahexaenoic acid(DHA)pathway may be one of the mechanisms of kidney injury in ***,we also found that melatonin attenuates PS-NPs-induced nephrotoxicity by modulating lipid metabolism disorders(represented by DHA)and affects Fasn *** conclusion,our study revealed the important role of intestinal flora-mediated lipid metabolism in PS-NPs-induced nephrotoxicity and preliminarily provided potential key gene targets and effective preventive measures for PS-NPs-induced nephrotoxicity.

关键词： nanoplastics nephrotoxicity lipid metabolism fatty acid synthase(Fasn) melatonin

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Filamentous morphology engineering of bacteria by iron metabolism modulation through MagR expression

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Synthetic and Systems Biotechnology 2024年第3期9卷 522-530页

作者： Mengke Wei Chenyang Han Xiujuan Zhou Tianyang Tong Jing zhang Xinmiao Ji Peng zhang Yanqi zhang Yan Liu Xin zhang Tiantian Cai Can Xie Institutes of Physical Science and Information Technology Anhui UniversityHefeiAnhui230039China High Magnetic Field Laboratory Hefei Institutes of Physical ScienceChinese Academy of SciencesScience IslandHefeiAnhui230031China Science Island Branch of Graduate School University of Science and Technology of ChinaHefeiAnhui230036China Department of Anatomy Anhui Medical UniversityHefeiAnhui230032China Institute of Quantum Sensing Zhejiang UniversityHangzhouZhejiang310027China

The morphology is the consequence of evolution and *** coli is rod-shaped bacillus with regular dimension of about 1.5μm long and 0.5μm *** shape-related genes have been identified and used in morphology engineering of this ***,little is known about if specific metabolism and metal irons could modulate bacteria *** in this study,we discovered filamentous shape change of *** cells overexpressing pigeon MagR,a putative magnetoreceptor and extremely conserved iron-sulfur *** transcriptomic analysis strongly suggested that the iron metabolism change and iron accumulation due to the overproduction of MagR was the key to the morphological *** model was further validated,and filamentous morphological change was also achieved by supplement *** cells with iron in culture medium or by increase the iron uptake genes such as entB and *** study extended our understanding of morphology regulation of bacteria,and may also serves as a prototype of morphology engineering by modulating the iron metabolism.

关键词： Morphology regulation Iron accumulation Filamentous bacteria MagR overexpression

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Different lymph node staging systems for predicting the prognosis of colorectal neuroendocrine neoplasms

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1745-1755页

作者： Yuan-Yi zhang Yue-Wei Cai Xia zhang Department of Pathology Zhaoqing Medical CollegeZhaoqing 526020Guangdong ProvinceChina Department of Emergency Zhaoqing Second People’s HospitalZhaoqing 526020Guangdong ProvinceChina Department of Pathology and Physiology Zhaoqing Medical CollegeZhaoqing 526020Guangdong ProvinceChina

BACKGROUND Colorectal neuroendocrine neoplasms(NENs)are a rare malignancy that primarily arises from the diffuse distribution of neuroendocrine cells in the colon and *** studies have pointed out that the status of lymph node may be used to predict the *** To investigate the predictive values of lymph node ratio(LNR),positive lymph node(PLN),and log odds of PLNs(LODDS)staging systems on the prognosis of colorectal NENs treated surgically,and compare their predictive *** This cohort study included 895 patients with colorectal NENs treated surgically from the Surveillance,Epidemiology,and End Results *** endpoint was mortality of patients with colorectal NENs treated surgically.X-tile software was utilized to identify most suitable thresholds for categorizing the LNR,PLN,and *** were selected in a random manner to form training and testing *** prognosis of surgically treating colorectal NENs was examined using multivariate cox analysis to assess the associations of LNR,PLN,and LODDS with the prognosis of colorectal NENs.C-index was used for assessing the predictive *** conducted a subgroup analysis to explore the different lymph node staging systems’predictive *** After adjusting all confounding factors,PLN,LNR and LODDS staging systems were linked with mortality in patients with colorectal NENs treated surgically(P<0.05).We found that LODDS staging had a higher prognostic value for patients with colorectal NENs treated surgically than PLN and LNR staging *** results were obtained in the different G staging subgroup ***,the area under the receiver operating characteristic curve values for LODDS staging system remained consistently higher than those of PLN or LNR,even at the 1-,2-,3-,4-,5-and 6-year follow-up *** LNR,PLN,and LODDS were found to significantly predict the prognosis of patients with colorectal NENs treated surgically.

关键词： Positive lymph node Lymph node ratio Log odds of positive lymph nodes Prognosis Colorectal neuroendocrine neoplasms

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Deep learning CNN-APSO-LSSVM hybrid fusion model for feature optimization and gas-bearing prediction

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Petroleum Science 2024年第4期21卷 2329-2344页

作者： Jiu-Qiang Yang Nian-Tian Lin Kai zhang Yan Cui Chao Fu Dong zhang College of Earth Sciences and Engineering Shandong University of Science and Technology Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Transportation Institute of Inner Mongolia University Key Laboratory of Gas Hydrate Qingdao Institute of Marine Geology Ministry of Natural Resources

Conventional machine learning(CML) methods have been successfully applied for gas reservoir prediction. Their prediction accuracy largely depends on the quality of the sample data; therefore, feature optimization of the input samples is particularly important. Commonly used feature optimization methods increase the interpretability of gas reservoirs; however, their steps are cumbersome, and the selected features cannot sufficiently guide CML models to mine the intrinsic features of sample data efficiently. In contrast to CML methods, deep learning(DL) methods can directly extract the important features of targets from raw data. Therefore, this study proposes a feature optimization and gas-bearing prediction method based on a hybrid fusion model that combines a convolutional neural network(CNN)and an adaptive particle swarm optimization-least squares support vector machine(APSO-LSSVM). This model adopts an end-to-end algorithm structure to directly extract features from sensitive multicomponent seismic attributes, considerably simplifying the feature optimization. A CNN was used for feature optimization to highlight sensitive gas reservoir information. APSO-LSSVM was used to fully learn the relationship between the features extracted by the CNN to obtain the prediction results. The constructed hybrid fusion model improves gas-bearing prediction accuracy through two processes of feature optimization and intelligent prediction, giving full play to the advantages of DL and CML methods. The prediction results obtained are better than those of a single CNN model or APSO-LSSVM model. In the feature optimization process of multicomponent seismic attribute data, CNN has demonstrated better gas reservoir feature extraction capabilities than commonly used attribute optimization methods. In the prediction process, the APSO-LSSVM model can learn the gas reservoir characteristics better than the LSSVM model and has a higher prediction accuracy. The constructed CNN-APSO-LSSVM mode

关键词： Multicomponent seismic data Deep learning Adaptive particle swarm optimization Convolutional neural network Least squares support vector machine Feature optimization Gas-bearing distribution prediction

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Effects of thinning and understory removal on water use efficiency of Pinus massoniana:evidence from photosynthetic capacity and stable carbon isotope analyses

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Journal of Forestry Research 2024年第2期35卷 42-53页

作者： Ting Wang Qing Xu Beibei zhang Deqiang Gao Ying zhang Jing Jiang Haijun Zuo Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration Ecology and Nature Conservation InstituteChinese Academy of ForestryBeijing 100091People’s Republic of China College of Agronomy and Agricultural Engineering Liaocheng UniversityLiaocheng 252000People’s Republic of China Department of Forest and Conservation Sciences Faculty of ForestryUniversity of British ColumbiaVancouverBC V6T 1Z4Canada

Understanding the relationship between forest management and water use efficiency(WUE)is important for evaluating forest adaptability to climate ***,the effects of thinning and understory removal on WUE and its key controlling processes are not well understood,which limits our comprehension of the physiological mechanisms of various management *** this study,four forest management measures(no thinning:NT;understory removal:UR;light thinning:LT;and heavy thinning:HT)were carried out in Pinus massoniana plantations in a subtropical region of *** capacity and needle stable carbon isotope composition(δ^(13)C)were measured to assess instantaneous water use efficiency(WUE_(inst))and long-term water use efficiency(WUE_(i)).Multiple regression models and structural equation modelling(SEM)identified the effects of soil properties and physiological performances on WUE_(inst)and WUE_(i).The results show that WUE_(inst)values among the four treatments were ***,compared with the NT stand(35.8μmol·mol^(-1)),WUE_(i)values significantly increased to 41.7μmol·mol^(-1)in the UR,50.1μmol·mol^(-1)in the LT and 46.6μmol·mol^(-1)in HT treatments,largely explained by photosynthetic capacity and soil water *** removal did not change physiological performance(needle water potential and photosynthetic capacity).Thinning increased the net photosynthetic rate(A_n)but not stomatal conductance(g_s)or predawn needle water potential(ψ_(pd)),implying that the improvement in water use efficiency for thinned stands was largely driven by radiation interception than by soil water *** general,thinning may be an appropriate management measure to promote *** WUE to cope with seasonal droughts under future extreme climates.

关键词： Stable carbon isotope Water use efficiency Thinning Understory removal Photosynthetic capacity Needle water potential

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