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Science China Chemistry 2024年第7期67卷 2199-2205页

作者： Hongyan Long sha zhao Chunyan Jian Xiuli Wu Fengfei Lu Minghong Liao Fengrui Che Xingxing Wu Yonggui Robin Chi State Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityGuiyang 550025China School of Chemistry Chemical Engineeringand BiotechnologyNanyang Technological UniversitySingapore 637371Singapore

Organoseleniums exhibit a diverse set of biological activities that are pivotal for drug discovery and are widely explored in synthetic chemistry and material science.While many transformations have been developed for non-enantioselective C–Se bond formations,the catalyst-controlled stereoselective preparation of chiral organoseleniums continues to be of considerable challenge.In particular,there are limited studies on the enantioselective seleno-Michael addition reactions to access chiral selenium functional molecules.Here,we disclose a carbene-catalyzed highly enantioselective nucleophilic C–Se bond construction through formal[3+3]annulations between selenocarboxamides and bromoenals,affording seleno-thiazinone products with good yields and excellent enantioselectivities.The choice of a weak inorganic base was pivotal to suppressing the unproductive racemization and decomposition of the selenium products.Notably,the catalytically generated chiral selenium-containing heterocyclic products feature remarkable antimicrobial activities that could serve as promising lead scaffolds for further agrochemical development.

关键词： seleno-Michael addition organocatalysis N-heterocyclic carbene seleno-heterocycles antimicrobial activity

Land use and cover change and influencing factor analysis in the Shiyang River Basin,China

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Journal of Arid Land 2024年第2期16卷 246-265页

作者： zhao Yaxuan CAO Bo sha Linwei CHENG Jinquan zhao Xuanru GUAN Weijin PAN Baotian Key Laboratory of Western China's Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730030China Shiyang River Basin Scientific Observing Station Lanzhou UniversityLanzhou 730030China

Land use and cover change(LUCC)is the most direct manifestation of the interaction between anthropological activities and the natural environment on Earth's surface,with significant impacts on the environment and social economy.Rapid economic development and climate change have resulted in significant changes in land use and cover.The Shiyang River Basin,located in the eastern part of the Hexi Corridor in China,has undergone significant climate change and LUCC over the past few decades.In this study,we used the random forest classification to obtain the land use and cover datasets of the Shiyang River Basin in 1991,1995,2000,2005,2010,2015,and 2020 based on Landsat images.We validated the land use and cover data in 2015 from the random forest classification results(this study),the high-resolution dataset of annual global land cover from 2000 to 2015(AGLC-2000-2015),the global 30 m land cover classification with a fine classification system(GLC_FCS30),and the first Landsat-derived annual China Land Cover Dataset(CLCD)against ground-truth classification results to evaluate the accuracy of the classification results in this study.Furthermore,we explored and compared the spatiotemporal patterns of LUCC in the upper,middle,and lower reaches of the Shiyang River Basin over the past 30 years,and employed the random forest importance ranking method to analyze the influencing factors of LUCC based on natural(evapotranspiration,precipitation,temperature,and surface soil moisture)and anthropogenic(nighttime light,gross domestic product(GDP),and population)factors.The results indicated that the random forest classification results for land use and cover in the Shiyang River Basin in 2015 outperformed the AGLC-2000-2015,GLC_FCS30,and CLCD datasets in both overall and partial validations.Moreover,the classification results in this study exhibited a high level of agreement with the ground truth features.From 1991 to 2020,the area of bare land exhibited a decreasing trend,with changes primarily occurring in the middle and lower

关键词： land use and cover classification land use and cover change(LUCC) climate change random forest accuracy assessment three-dimensional sampling method Shiyang River Basin

Creep property and microstructural evolution of DD11 alloy under high temperature and low stress

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Rare Metals 2024年第2期43卷 810-816页

作者： Yan-Fei Liu Jiang-Bo sha Yun-Song zhao Chen-Guang Liu Yuan-Yuan Guo Jian Zhang Yu-Shi Luo School of Materials Science and Engineering Beihang UniversityBeijing100191China Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical MaterialsBeijing100095China

In this paper,the interrupted and ruptured creep tests were carried out in a novel second generation single crystal superalloy named DD11 at 1100℃/130 MPa.The alloy exhibited typical creep curve including primary,steady,and tertiary three creep stages.The microstructural evolution at different stages of the creep were analyzed by scanning electron microscopy(SEM)and transmission electron microscopy(TEM).The results show that theγ′phases transform into rafted structure at the early stage of the steady creep and keep stable during the steady creep stage.As the creep goes on,the rafted structure further coarsens and the topological inversion occurs.In addition,at the primary creep,the dislocations mainly move in theγmatrix and pile up in theγ/γ′interface since the matrix channels widen slightly.The formation of the regular interfacial dislocation networks occurs at the early stage of the steady creep.Under the low stress,the dominated deformation mechanism during steady creep stage is the climbing of the〈010〉type edge dislocation.Furthermore,the effect of the deformation mechanism on creep property was discussed in detail.

关键词： DD11 alloy Creep property Interrupted creep test Rafted structure Deformation mechanism

Stay in touch with the endoplasmic reticulum

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Science China(Life Sciences) 2024年第2期67卷 230-257页

作者： sha Sun Gan zhao Mingkang Jia Qing Jiang Shulin Li Haibin Wang Wenjing Li Yunyun Wang Xin Bian Yan G.zhao Xun Huang Ge Yang Huaqing Cai Jose C.Pastor-Pareja Liang Ge Chuanmao Zhang Junjie Hu National Laboratory of Biomacromolecules Institute of BiophysicsUniversity of Chinese Academy of SciencesChinese Academy of SciencesBeijing 100101China The Ministry of Education Key Laboratory of Cell Proliferation and Differentiation College of Life SciencesPeking UniversityBeijing 100871China State Key Laboratory of Membrane Biology Tsinghua-Peking Center for Life SciencesSchool of Life SciencesTsinghua UniversityBeijing 100084China Laboratory of Computational Biology&Machine Intelligence School of Artificial IntelligenceUniversity of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Medicinal Chemical Biology College of Life SciencesNankai UniversityTianjin 300071China Brain Research Center Department of BiologySchool of Life SciencesSouthern University of Science and TechnologyShenzhen 518055China State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental BiologyInnovation Academy for Seed DesignChinese Academy of SciencesBeijing 100101China Institute of Neurosciences Consejo Superior de Investigaciones Científicas-Universidad Miguel HernándezSan Juan de Alicante 03550Spain

The endoplasmic reticulum(ER),which is composed of a continuous network of tubules and sheets,forms the most widely distributed membrane system in eukaryotic cells.As a result,it engages a variety of organelles by establishing membrane contact sites(MCSs).These contacts regulate organelle positioning and remodeling,including fusion and fission,facilitate precise lipid exchange,and couple vital signaling events.Here,we systematically review recent advances and converging themes on ER-involved organellar contact.The molecular basis,cellular influence,and potential physiological functions for ER/nuclear envelope contacts with mitochondria,Golgi,endosomes,lysosomes,lipid droplets,autophagosomes,and plasma membrane are summarized.

关键词： endoplasmic reticulum nuclear envelope mitochondria Golgi apparatus endosome lysosome lipid droplets autophagosome plasma membrane membrane contact site

Dynamic road crime risk prediction with urban open data

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Frontiers of Computer Science 2022年第1期16卷 113-125页

作者： Binbin ZHOU Longbiao CHEN Fangxun ZHOU Shijian LI sha zhao Gang PAN College of Computer Science Zhejiang UniversityHangzhou310027China Fujian Key Laboratory of Sensing and Computing for Smart Cities School of Information Science and EngineeringXiamen UniversityXiamen361005China

Crime risk prediction is helpful for urban safety and citizens’life quality.However,existing crime studies focused on coarse-grained prediction,and usually failed to capture the dynamics of urban crimes.The key challenge is data sparsity,since that 1)not all crimes have been recorded,and 2)crimes usually occur with low frequency.In this paper,we propose an effective framework to predict fine-grained and dynamic crime risks in each road using heterogeneous urban data.First,to address the issue of unreported crimes,we propose a cross-aggregation soft-impute(CASI)method to deal with possible unreported crimes.Then,we use a novel crime risk measurement to capture the crime dynamics from the perspective of influence propagation,taking into consideration of both time-varying and location-varying risk propagation.Based on the dynamically calculated crime risks,we design contextual features(i.e.,POI distributions,taxi mobility,demographic features)from various urban data sources,and propose a zero-inflated negative binomial regression(ZINBR)model to predict future crime risks in roads.The experiments using the real-world data from New York City show that our framework can accurately predict road crime risks,and outperform other baseline methods.

关键词： crime prediction road crime risk urban computing data sparsity zero-inflated negative binomial regression

Comprehensive reutilization of herbal waste:Coproduction of magnolol,honokiol,and β-amyrin from Magnolia officinalis residue

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Green Energy & Environment 2024年第2期9卷 403-412页

作者： Lukun Xiao Anyi zhao Jie Qiu An Liu sha Chen Jinzhu Jiang Jun Zhang Cong Guo Jipeng Di Jintang Cheng Chang Chen Kangxin Hou Aiping Zhang Yan Liu Caixia Wang Institute of Chinese Materia Medica China Academy of Chinese Medical SciencesBeijing100700China School of Pharmacy Shanxi Medical UniversityTaiyuan030001China

Herbal extraction residues(HERs)cause serious environmental pollution and resource waste.In this study,a novel green route was designed for the comprehensive reutilization of all components in HERs,taking Magnolia officinalis residues(MOR)as an example.The reluctant structure of MOR was first destroyed by alkali pretreatment to release the functional ingredients(magnolol and honokiol)originally remaining in MOR and to make MOR more accessible for hydrolysis.A metal–organic frame material MIL-101(Cr)with a maximum absorption capacity of 255.64 mg g^(-1)was synthesized to absorb the released honokiol and magnolol from the pretreated MOR solutions,and 40 g L^(-1)reducing sugars were obtained with 81.8%enzymatic hydrolysis rate at 10%MOR solid loading.Finally,382 mg L-1β-amyrin was produced from MOR hydrolysates by an engineered yeast strain.In total,1 kg honokiol,8 kg magnolol,and 7.64 kg β-amyrin could produce from 1 ton MOR by this cleaner process with a total economic output of 170,700 RMB.

关键词： Magnolia officinalis residues(MOR) Comprehensive utilization Metal-organic frame material Biosynthesis

In situ forming injectable MSC-loaded GelMA hydrogels combined with PD for vascularized sweat gland regeneration

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Military Medical Research 2024年第1期11卷 152-155页

作者： Enhe Jirigala Bin Yao zhao Li Yi-Jie Zhang Chao Zhang Li-Ting Liang Fan-Liang Zhang Xing-Yu Yuan Xian-Lan Duan Wei Song Meng-De Zhang Yi Kong Xiao-Bing Fu sha Huang Research Center for Tissue Repair and Regeneration Medical Innovation Research DepartmentChinese PLA General Hospital and PLA Medical CollegeBeijing 100048China Institute of Basic Medical Research Inner Mongolia Medical UniversityHohhot 010110China Academy of Medical Engineering and Translational Medicine Tianjin UniversityTianjin 300072China School of Medicine Nankai UniversityTianjin 300071China

Dear Editor,Three dimensional(3D)bioprinted extracellular matrix(ECM)can be used to provide both biochemical and biophysical cues to direct mesenchymal stem cells(MSCs)differentiation,and then differentiated cells were isolated for implantation in vivo using surgical procedures.However,the reduced cell activity after cell isolation from 3D constructs and low cell retention in injured sites limit its application[1].Methacrylated gelatin(GelMA)hydrogel has the advantage of fast crosslinking,which could resemble complex architectures of tissue construct in vivo[2].Here,we adopted a noninvasive bioprinting procedure to imitate the regenerative microenvironment that could simultaneously direct the sweat gland(SG)and vascular differentiation from MSCs and ultimately promote the replacement of glandular tissue in situ(Fig.1a).

关键词： Sweat gland GelMA In situ niche Cell differentiation Tissue incorporation Vascularization

重新审视面向CNN模型的测试样例选取:考虑模型校准

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计算机科学 2024年第6期51卷 34-43页

作者：赵通沙朝锋复旦大学计算机科学技术学院上海200433

深度神经网络(DNN)已被广泛应用于各种任务,而在部署前对DNN进行充分测试尤为重要,因此需要构建能够对DNN进行充分测试的测试集。由于标注成本受限,通常通过测试样例选取的方式得到测试子集。然而,人们使用基于预测不确定性的方法(该方... 详细信息

深度神经网络(DNN)已被广泛应用于各种任务,而在部署前对DNN进行充分测试尤为重要,因此需要构建能够对DNN进行充分测试的测试集。由于标注成本受限,通常通过测试样例选取的方式得到测试子集。然而,人们使用基于预测不确定性的方法(该方法在发现误分类样例和提升重训练表现方面表现出卓越的能力)进行测试样例选取时,忽略了对测试样例的预测不确定性估计是否准确的问题。为了填补上述研究的空白,通过实验定性和定量地揭示了模型校准程度和测试样例选取任务中使用的不确定性指标之间的相关性。校准模型会使模型有更准确的预测不确定性估计,因此研究了不同校准程度的模型用不确定指标选取得到的测试子集质量是否不同。在3个公开数据集和4个卷积神经网络(CNN)架构模型上进行了充分的实验和分析,结果表明在CNN架构模型上:1)不确定指标和模型校准存在一定程度的相关性;2)校准程度好的模型所选择的测试子集质量优于校准程度差的模型选择的测试子集质量。在发现模型误分类样例的能力上,70.57%经过校准训练后的模型对应的实验结果优于未校准模型对应的实验结果。因此在测试样例选取任务中考虑模型校准十分重要,且可以使用模型校准来提升测试样例选取的表现。

关键词：卷积神经网络测试预测不确定性模型校准测试样例选取

Relationship Between Climate Change and Marmot Plague of Marmota himalayana Plague Focus—the Altun Mountains of the Qinghai-Xizang Plateau,China,2000–2022

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China CDC weekly 2024年第4期6卷 69-74,I0006页

作者： Qun Duan Xiaojin Zheng Zhiqiang Gan Dongyue Lyu Hanyu sha Xinmin Lu Xiaoling zhao Asaiti Bukai Ran Duan Shuai Qin Li Wang Jinxiao Xi Di Wu Peng Zhang Deming Tang zhaokai He Huaiqi Jing Biao Kan Xin Wang National Institute for Communicable Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina Akesai Kazak Autonomous County Center for Disease Control and Prevention Jiuquan CityGansu ProvinceChina Jiuquan Center for Disease Control and Prevention Jiuquan CityGansu ProvinceChina Gansu Provincial Center for Disease Control and Prevention Lanzhou CityGansu ProvinceChina

Introduction:Plague is a zoonotic disease that occurs naturally in specific geographic areas.Climate change can influence the populations of the plague host or vector,leading to variations in the occurrence and epidemiology of plague in animals.Methods:In this study,we collected meteorological and plague epidemiological data from the Marmota himalayana plague focus in the Altun Mountains of the Qinghai-Xizang Plateau.The data spanned from 2000 to 2022.We describe the climatic factors and plague epidemic conditions and we describe their analysis by Pearson’s correlation.Results:During the period from 2000 to 2022,the isolation rates of Yersinia pestis(Y.pestis)from marmots and fleas were 9.27%(451/4,864)and 7.17%(118/1,646),respectively.Additionally,we observed a positive rate of F1 antibody of 11.25%(443/3,937)in marmots and 18.16%(142/782)in dogs.With regards to climate,there was little variation,and a decreasing trend in blowing-sand days was observed.The temperature in the previous year showed a negative correlation with the Y.pestis isolation rate in marmots(r=−0.555,P=0.011)and the positive rate of F1 antibody in marmots(r=−0.552,P=0.012)in the current year.The average annual precipitation in the previous two years showed a positive correlation with marmot density(r=0.514,P=0.024),while blowingsand days showed a negative correlation with marmot density(r=−0.701,P=0.001).Furthermore,the average annual precipitation in the previous three years showed a positive correlation with the isolation rate of Y.pestis from marmots(r=0.666,P=0.003),and blowing-sand days showed a negative correlation with marmot density(r=−0.597,P=0.009).Conclusions:The findings of this study indicate that there is a hysteresis effect of climate change on the prevalence of plague.Therefore,monitoring climate conditions can offer significant insights for implementing timely preventive and control measures to combat plague epidemics.

关键词： Plague epidemiology Plateau

第5版WHO造血与淋巴组织肿瘤分类T/NK细胞增生性疾病和淋巴瘤解读

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中华病理学杂志 2024年第6期53卷 535-540页

作者：赵莎李甘地刘卫平四川大学华西医院病理科成都610041

第5版WHO造血与淋巴组织肿瘤分类对T细胞和NK细胞增生性疾病和淋巴瘤(T-cell and NK-cell lymphoid proliferations and lymphomas,T/NK-LPD/LYM)根据研究进展以及疾病的临床病理特征,采用了分级系统进行分类。同时纳入了瘤样病变,引入... 详细信息

第5版WHO造血与淋巴组织肿瘤分类对T细胞和NK细胞增生性疾病和淋巴瘤(T-cell and NK-cell lymphoid proliferations and lymphomas,T/NK-LPD/LYM)根据研究进展以及疾病的临床病理特征,采用了分级系统进行分类。同时纳入了瘤样病变,引入/删除一些肿瘤,修改某些疾病的名称,并修订一些疾病的诊断标准或亚型,将这组疾病从非克隆性增生到高度侵袭性淋巴瘤进行了重新整合,更体现了T/NK-LPD/LYM的疾病本质,有利于临床应用。

关键词： T淋巴细胞杀伤细胞,天然分类淋巴