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Regional Climate Change and Uncertainty Analysis based on Four Regional Climate Model Simulations over China

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Atmospheric and Oceanic Science Letters 2015年第3期8卷 147-152页

作者： WU Jia GAO xue-Jie xu yin-long PAN Jie National Climate Center China Meteorological Administration Climate Change Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences

Four sets of climate change simulations at grid spacing of 50 km were conducted over East Asia with two regional climate models driven at the lateral boundaries by two global models for the period 1981–2050. The focus of the study was on the ensemble projection of climate change in the mid-21 st century(2031–50) over China. Validation of each simulation and the ensemble average showed good performances of the models overall, as well as advantages of the ensemble in reproducing present day(1981–2000) December–February(DJF), June–August(JJA), and annual(ANN) mean temperature and precipitation. Significant warming was projected for the mid-21 st century, with larger values of temperature increase found in the northern part of China and in the cold seasons. The ensemble average changes of precipitation in DJF, JJA, and ANN were determined, and the uncertainties of the projected changes analyzed based on the consistencies of the simulations. It was concluded that the largest uncertainties in precipitation projection are in eastern China during the summer season(monsoon precipitation).

关键词：区域气候变化中国东部地区不确定性分析模式模拟区域气候模式平均气温降水量全球模式

Contribution of Drought to Potential Crop Yield Reduction in a Wheat-Maize Rotation Region in the North China Plain

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Journal of Integrative Agriculture 2014年第7期13卷 1509-1519页

作者： HU Ya-nan LIU ying-jie TANG Hua-jun xu yin-long PAN Jie Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences Key Laboratory of Agri-Informatics Ministry of Agriculture/Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Public Meteorological Service Center Chinese Meteorological Administration

With consecutive occurrences of drought disasters in China in recent years, it is important to estimate their potential impacts on regional crop production. In this study, we detect the impacts of drought on wheat and maize yield and their changes at a 0.5＆#176;＆#215;0.5＆#176; grid scale in the wheat-maize rotation planting area in the North China Plain under the A1B climate change scenario using the Decision Support System for Agrotechnology Transfer （DSSAT） model and the outputs of the regional climate modeling system-Providing Regional Climates for Impacts Studies （PRECIS）. Self-calibrating palmer drought severity index was used as drought recognition indicator. Two time slices used for the study were the baseline （1961-1990） and 40 years of 2011-2050. The results indicate that the potential planting region for double crop system of wheat-maize would expend northward. The statistic conclusions of crop simulations varied considerably between wheat and maize. In disaster-affected seasons, wheat yield would increase in the future compared with baseline yields, whereas in opposite for maize yield. Potential crop yield reductions caused by drought would be lower for wheat and higher for maize, with a similar trend found for the ratio of potential crop yield reductions for both crops. It appears that the negative impact of drought on maize was larger than that on wheat under climate change A1B scenario.

关键词： drought yield DSSAT A1B scenario climate change

Correlation Analysis of Rice Seed Setting Rate and Weight of 1 000-Grain and Agro-Meteorology over the Middle and Lower Reaches of the Yangtze River,China

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Agricultural Sciences in China 2007年第4期6卷 430-436页

作者： ZHAO Hai-yan YAO Feng-mei ZHANG Yong xu Bin YUAN Jing HU Ya-nan xu yin-long Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences Beijing 100081 P.R China Graduate University Chinese Academy of Sciences Beijing 100039 P.R.China Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 P.R. China

The purpose of this study is to reveal the effects of historic climate change on rice yield over the middle and lower reaches of the Yangtze River, China, and to better adapt to climate change in the future. This study presents the relation of temperature and precipitation and rice components from 1981 to 2003 at 48 early rice stations and 30 middle rice stations. It focuses on an analysis of three stages： flowering, pre-milk, and late milk. The results show that mean maximum temperature and mean daily precipitation at the stages of flowering and pre-milk are most related to early rice yield. Yield change of middle rice is mainly because of mean precipitation change at the flowering stage. Furthermore, percentage of undeveloped grain increases as mean maximum temperature rises at the flowering stage. Over-precipitation in the reproductive stage is a major reason for reduction in yield of early rice. Consecutive rainfall and continuous high temperature can have negative effects on middle rice yield. Global warming would affect middle rice more seriously than early rice.

关键词： mean maximum temperature mean daily precipitation percentage of undeveloped grain percentage of partially developed grain weight of 1 000-grain

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基于输入特征稀疏化的图神经网络训练加速

计算机系统应用 2024年第1期33卷 245-253页

作者：马煜昕许胤龙李诚钟锦中国科学技术大学计算机科学与技术学院合肥230026 合肥师范学院计算机与人工智能学院合肥230601 合肥综合性国家科学中心人工智能研究院合肥230026

图神经网络(graph neural network,GNN)是处理图数据的重要方法.由于计算复杂、图数据容量大,在大规模图上训练图神经网络依赖于CPU-GPU协作和图采样训练方法,其中图结构和特征数据存储在CPU内存中,而采样得到的子图及其特征则传输至GP... 详细信息

图神经网络(graph neural network,GNN)是处理图数据的重要方法.由于计算复杂、图数据容量大,在大规模图上训练图神经网络依赖于CPU-GPU协作和图采样训练方法,其中图结构和特征数据存储在CPU内存中,而采样得到的子图及其特征则传输至GPU进行训练.然而,这种方法面临着严重的图特征数据加载瓶颈,显著降低了端到端训练性能,且图特征占用过多内存,严重限制了可训练的图规模.为了解决这些问题,我们提出了基于输入特征稀疏化的数据加载方法,显著减少CPU内存占用和跨PCIe总线传输的数据量,大幅缩短数据加载时间,加速GNN的训练,使其可以充分利用GPU计算资源.针对图特征和GNN计算特性,我们提出了适用于图特征数据的稀疏化方法,在压缩比和模型准确度之间达到平衡.我们在3个常见GNN模型和3个不同规模的数据集上进行了实验评估,包括最大的公开数据集之一MAG240M.结果表明,此方法将特征尺寸减小了一个数量级以上,并实现1.6-6.7倍的端到端训练加速,而模型准确度的降低不超过1%.此外,在仅使用4个GPU的情况下,仅需40 min就可以在MAG240M上完成GraphSAGE模型的训练并达到目标准确度.

关键词：图神经网络数据加载稀疏化压缩特征分析

Immediate implantation of ultrafine fiber slow-release system based on cell electrospinning to induce osteogenesis of mesenchymal stem cells

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Regenerative Biomaterials 2024年第2期3卷 76-87页

作者： Tao Lu long Yang Zhuoyang Li yin Liu Shun'en xu Chuan Ye Department of Orthopaedics The Affliated Hospital of Guizhou Medical UniversityGuiyang 550004China Department of Orthopaedics The First People's Hospital of GuiyangGuiyang 550004China Center for Tissue Engineering and Stem Cell Research Guizhou Medical UniversityGuiyang 550004China Department of Otolaryngology Head and Neck Surgery Xinqiao HospitalArmy Medical University(Third Military Medical University)Chongqing 400037China Department of Dental implant Stomatological Hospital of GuiyangGuiyang 550000China

This study presents the development and evaluation of a poly(3-hydroxybutyrate-co-4-hydroxybutyrate)(P34HB)ultrafine fiber slow-release system for in vivo osteogenic induction of human umbilical cord mesenchymal stem cells(HUCMSCs).Utilizing dual-nozzle and cell electrospinning techniques,the system encapsulates L-ascorbic acid-2-phosphate magnesium(AsP),βB-glycerophosphate sodium and dexamethasone(DEX)within the'fbers,ensuring sustained osteogenic differentiation.The scaffold's morphology,characterization,hydrophilicity,mechanical properties and cellular behavior were examined.Immediate subcutaneous implantation in rabbits was con-ducted to observe its ectopic osteogenic induction effect.Successfully fabricated P34HB ultrafine fiber slow-release sys-tem.Charact ization med.theuniform distribution of HUCMSCs and inducing components within the scaffold,with no chemical reactions affecting the active components.In vitro tests showcased a prolonged release of DEX and ASP,while biocompatibility assays highlighted the scaffold's suitability for cellular growth.Alizarin Red,type I collagen,and osteopontin(OPN)staining verifed the scaffold's potent osteogenic induction effect on HUCMsCs.Notably,immediate implantation into New Zealand White rabbits led to significant new bone formation within 8 weeks.These findings underscore the system's potential for immediate in vivo implantation without prior in vitro induction,marking a promising advancement in bone tissue engineering.

关键词： bone tissue engineering cell electrospinning in vivo induction immediate implantation biomaterials

Quantum Neural Network for Quantum Neural Computing

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Research 2024年第1期2023卷 71-80页

作者： Min-Gang Zhou Zhi-Ping Liu Hua-Lei yin Chen-long Li Tong-Kai xu Zeng-Bing Chen National Laboratory of Solid State Microstructures School of PhysicsCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China MatricTime Digital Technology Co.Ltd. Nanjing 211899China

Neural networks have achieved impressive breakthroughs in both industry and academia.How to effectively develop neural networks on quantum computing devices is a challenging open problem.Here,we propose a new quantum neural network model for quantum neural computing using(classically controlled)single-qubit operations and measurements on real-world quantum systems with naturally occurring environment-induced decoherence,which greatly reduces the difficulties of physical implementations.Our model circumvents the problem that the state-space size grows exponentially with the number of neurons,thereby greatly reducing memory requirements and allowing for fast optimization with traditional optimization algorithms.We benchmark our model for handwritten digit recognition and other nonlinear classification tasks.The results show that our model has an amazing nonlinear classification ability and robustness to noise.Furthermore,our model allows quantum computing to be applied in a wider context and inspires the earlier development of a quantum neural computer than standard quantum computers.

关键词： quantum thereby breakthrough

Protective Effects of Danmu Extract Syrup on Acute Lung Injury Induced by Lipopolysaccharide in Mice through Endothelial Barrier Repair

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Chinese Journal of Integrative Medicine 2024年第3期30卷 243-250页

作者： xu Han xu Si-cong LI Li-yan WU Yu-huang TAN yin-feng CHEN long LIU Pei LIANG Chang-fu HE Xiao-ning LI Yong-hui Hainan Provincial Key Lab of Research&Development on Tropic Herbs Hainan Medical UniversityHaikou571199China Department of Stomatology the Second Affiliated Hospital of Hainan Medical UniversityHaikou571199China

Objective:To investigate the effects of Danmu Extract Syrup(DMS) on lipopolysaccharide(LPS)-induced acute lung injury(ALI) in mice and explore the mechanism.Methods:Seventy-two male Balb/C mice were randomly divided into 6 groups according to a random number table(n=12),including control(normal saline),LPS(5 mg/kg),LPS+DMS 2.5 mL/kg,LPS+DMS 5 mL/kg,LPS+DMS 10 mL/kg,and LPS+Dexamethasone(DXM,5 mg/kg) groups.After pretreatment with DMS and DXM,the ALI mice model was induced by LPS,and the bronchoalveolar lavage fluid(BALF) were collected to determine protein concentration,cell counts and inflammatory cytokines.The lung tissues of mice were stained with hematoxylin-eosin,and the wet/dry weight ratio(W/D) of lung tissue was calculated.The levels of tumor necrosis factor-α(TNF-α),interleukin(IL)-6 and IL-1βin BALF of mice were detected by enzyme linked immunosorbent assay.The expression levels of Claudin-5,vascular endothelial(VE)-cadherin,vascular endothelial growth factor(VEGF),phospho-protein kinase B(p-Akt) and Akt were detected by Western blot analysis.Results:DMS pre-treatment significantly ameliorated lung histopathological changes.Compared with the LPS group,the W/D ratio and protein contents in BALF were obviously reduced after DMS pretreatment(P<0.05 or P<0.01).The number of cells in BALF and myeloperoxidase(MPO) activity decreased significantly after DMS pretreatment(P<0.05 or P<0.01).DMS pre-treatment decreased the levels of TNF-α,IL-6 and IL-1β(P<0.01).Meanwhile,DMS activated the phosphoinositide 3-kinase/protein kinase B(PI3K/Akt) pathway and reversed the expressions of Claudin-5,VE-cadherin and VEGF(P<0.01).Conclusions:DMS attenuated LPS-induced ALI in mice through repairing endothelial barrier.It might be a potential therapeutic drug for LPS-induced lung injury.

关键词： Danmu Extract Syrup acute lung injury inflammatory factors vascular endothelial growth factor phosphoinositide 3-kinase/protein kinase B Chinese medicine Nauclea officinalis

Rapid and chemoselective imidation of sulfides in aqueous buffer enabled by a novel guanidine-derived N-O reagent

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Science China Chemistry 2024年第6期67卷 1929-1934页

作者： Hanzheng Li long xu Jiajia Dong Key Laboratory of Organofluorine Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai200032China Institute of Translational Medicine National Facility for Translational Medicine(Shanghai)Shanghai Jiao Tong UniversityShanghai200240China School of Chemistry and Chemical Engineering Zhangjiang Institute for Advanced StudyShanghai Jiao Tong UniversityShanghai200240China Shanghai Artificial Intelligence Laboratory Shanghai200232China

Herein we report the facile synthesis of a series of novel N-O reagents and identify N′-di-Boc-N′′-[(mesitylsulfonyl)oxy]-guanidine as an efficient imidating reagent.This reagent is synthetically scalable and bench-stable,yet it shows unprecedented reactivity and chemoselectivity towards S(II)in buffer/hexafluoroisopropanol(HFIP)system,to generate a new class of Nguanyl sulfilimines.Further transformation of N-guanyl sulfilimines to N-guanyl sulfoximines provides us a chance to investigate these rarely reached compounds,which are shown to be versatile precursors to a variety of N-heterocyclic and NHsulfoximines.Our work provides an addition to the tool box of both sulfur imidation and guanidine synthesis,especially for the need of rapid and selective modifications of sulfur(II)center under biocompatible conditions.

关键词： sulfur imidation N-O reagent

A novel strategy of tannery sludge disposal–converting into biochar and reusing for Cr(Ⅵ)removal from tannery wastewater

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Journal of Environmental Sciences 2024年第4期138卷 637-649页

作者： Zhiwei Li Di Yu Xingdong Wang xuejiao Liu Zhen xu yin Wang CAS Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China Zhejiang Key Laboratory of Urban Environmental Processes and Pollution Control CAS Haixi Industrial Technology Innovation Center in BeilunNingbo 315830China Key Laboratory of Urban Environment and Health Ningbo Observatio

Tannery sludge with high chromium content has been identified as hazardous solid waste due to its potential toxic effects.The safety disposal and valorization of the tannery sludge remains a challenge.In this study,the chromium stabilization mechanism was systematically investigated during chromium-rich tannery sludge was converted to biochar and the removal performance of the sludge biochar(SBC)for Cr(Ⅵ)from tannery wastewater was also investigated.The results showed that increase in pyrolysis temperature was conductive to the stabilization of Cr and significant reduction of the proportion of Cr(Ⅵ)in SBC.It was confirmed that the stabilization of chromium mainly was attributed to the embedding of chromium in the C matrix and the transformation of the chromium-containing substances from the amorphous Cr(OH)_(3)to the crystalline state,such as(FeMg)Cr_(2)O_(5).The biochar presented high adsorption capacity of Cr(Ⅵ)at low pH and the maximal theoretical adsorption capacity of SBC produced at 800°C can reach 352 mg Cr(Ⅵ)/g,the process of which can be well expressed by Langmuir adsorption isotherm and pseudo second order model.The electrostatic effect and reduction reaction were dominantly responsible for the Cr(Ⅵ)adsorption by SBC800.Overall,this study provided a novel strategy for the harmless disposal and resource utilization for the solid waste containing chromium in leather industry.

关键词： Chromium-rich tannery sludge Pyrolysis Biochar Stabilizationmechanisms Cr(Ⅵ)adsorption