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Acta Mechanica Sinica 2024年第6期40卷 115-124页

作者： Yang Gao Jiawei He Jie Jiang jianping Zuo School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing100083China

Inspired by nature,various biomimetic materials have been synthesized for enhanced mechanical properties,among which composites with brick-and-mortar structures attract the most *** such bio-inspired composites,the matrix layer mainly functions to transfer load between bricks through shearing,while the shear stress in the matrix is not uniform but highly concentrated on the interface ends,which tends to initiate cracks and evoke interface delamination in *** enhance the composites’resistance to interface delamination,we propose to homogenize the shear stress by adopting a matrix with a gradient modulus.A theoretical solution to the optimal gradient modulus of the matrix layer is obtained,followed by computational ***,composites with such functionally graded matrices are further demonstrated to possess higher elastic limits,higher resilience,and flaw tolerance than the uniform *** results of this paper should be of great value to the design and synthesis of advanced structural materials for superior mechanical performance.

关键词： Stress concentration Interface delamination Brick-and-mortar structure Composite

The synthesis of fluorescent nanoclusters based on the etching reaction

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Nano Research 2024年第5期17卷 4631-4638页

作者： Hongbin Lin Yitao Cao Qiaofeng Yao Tiankai Chen Huiting Shan jianping Xie Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207China Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore 117585Singapore National and Local Joint Engineering Research Center of MPTES in High Energy and Safety LIBs Engineering Research Center of MTEES(Ministry of Education)and Key Laboratory of ETESPG(GHEI)South China Normal UniversityGuangzhou 510006China Tianjin Key Laboratory of Molecular Optoelectronic Sciences Key Laboratory of Integrated Organic CircuitsMinistry of EducationDepartment of ChemistrySchool of ScienceTianjin UniversityTianjin 300072China

Thiolate-protected atomically precise nanoclusters(NCs)demonstrate a series of unique luminescent characteristics attributed to their various peculiar electronic ***,fluorescent NCs present extraordinary practical values in biosensing and bioimaging research ***,restricted by the types of fluorescent NCs,there are great difficulties in promoting the development of NCs in fluorescent research *** a result,it is of significant necessity for researchers to develop new synthetic pathways to produce high-quality fluorescent *** to the analysis about the structural characteristics of fluorescent NCs,some general features like longer motif and higher ligand-to-metal ratio can be found,consistent to some presented regularities in etching ***,in this work,we used Au_(2.)(MHA)_(18)(MHA=6-mercaptohexanoic acid)as a model nanocluster and utilized the etching reaction to systematically explore etching products and their corresponding luminescent ***,we also identified three main reaction processes in the entire etching reaction process,which can generate new metal nanocluster species with various fluorescent ***,the etching reaction will provide a good platform to produce new luminescent metal NC species.

关键词： etching reaction metal nanoclusters fluorescent properties fluorescent conversion

Preface to the Special Issue on Causes, Impacts, and Predictability of Droughts for the Past, Present, and Future

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Advances in Atmospheric Sciences 2024年第2期41卷 191-192页

作者： Tianbao ZHAO Aiguo DAI jianping HUANG Lixia ZHANG Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Institute of Atmospheric Physics(IAP)Chinese Academy of Sciences(CAS)Beijing 100029China Department of Atmospheric and Environmental Sciences University at AlbanySUNYAlbanyNew York 80307USA Key Laboratory for Semi-Arid Climate Change of the Ministry of Education Lanzhou UniversityLanzhou 730000China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Drought is a recurring dry condition with below-normal precipitation and is often associated with warm temperatures or heatwaves. A drought event can develop slowly over several weeks or suddenly within days, commonly under abnormal atmospheric conditions(e.g., quasi-stationary high-pressure systems), and can persist for weeks, months, or even years.

关键词： drought within suddenly

Compound events of heatwave and dust storm in the Taklamakan Desert

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Science China Earth Sciences 2024年第7期67卷 2073-2083页

作者： Yuzhi LIU jianping HUANG Ziyuan TAN Chenglong ZHOU Dan LI Yongkun XIE Key Laboratory for Semi-Arid Climate Change of the Ministry of Education Lanzhou UniversityLanzhou 730000China Collaborative Innovation Center for Western Ecological Safety Lanzhou UniversityLanzhou 730000China Taklamakan National Station of Observation and Research for Desert Meteorology in Xinjiang Urumqi 830002China

Taklamakan Desert(TD)has been characterized by numerous heatwaves and dust storms,leading to negative effects on societies and ecosystems at regional and global ***,the association between heatwaves and dust storms is poorly *** this study,we describe the association between heatwaves and dust events and propose a mechanism for such compound events in the *** results show that,from 1993 to 2.2.,the frequency and intensity of heatwaves in the TD have increased at a rate of 0.2. days year^(-1)and 0.02. year^(-1),*** than 40% of heatwaves existed with dust events,which significantly lagged behind ***,the higher the air temperature,the hotter and drier the soil,leading to more dust emissions in the *** high-occurrence heatwave years,a large-scale wave train of“cyclone-anticyclone-cyclone”in the northwest-southeast direction was found,with the anticyclone of which hovered over the TD *** anomalous anticyclones favored the formation and maintenance of heatwaves,and subsequent anomalous cyclones in the wave train triggered strong dust events followed by *** climate warming,the compound events of heatwave and dust storm are becoming bigger hazards threatening the socioeconomic and ecological security in the TD,the profound study of which is critical to understanding regional extreme responses.

关键词： Heatwave Dust storm Compound events Taklamakan Desert

Decoding aging:examining the non-evolutionary event from an evolutionary perspective

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Science China(Life Sciences) 2024年第9期67卷 2026-2029页

作者： Yannan Guo Kang Xu jianping Cai Zhao Wang Protein Science Key Laboratory of the Ministry of Education School of Pharmaceutical SciencesTsinghua UniversityBeijing 100084China Beijing Institute of Geriatrics Beijing HospitalNational Center of GerontologyNational Health CommissionBeijing 100730China

In an era marked by increased longevity,a deeper understanding of the older population is *** introducing an overlooked evolutionary perspective on aging,this article challenges traditional biogerontology,which primarily focuses on biological and clinical *** articulately differentiates between chronological and physiological aging,suggesting that aging is an evolutionary byproduct rather than a direct evolutionary event.

关键词： aging primarily evolutionary

Analyst Coverage,Forecasting Bias,and Corporate Innovation:Evidence from China

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Journal of Systems Science and Information 2024年第1期12卷 1-24页

作者： Xinping MA Yiru WANG jianping LI Biao SHI School of Economics and Management University of Chinese Academy of SciencesBeijing 100049China School of Finance Nankai UniversityTianjin 300071China Institutes of Science and Development Chinese Academy of SciencesBeijing 100190China

Due to information asymmetry and strategic innovation,firms often encounter challenges related to insufficient driving forces and low-quality innovation *** always act as information intermediaries who help foster the advancement of corporate innovation activities and the conversion of innovation *** study examines the impact of analyst coverage and forecasting bias on corporate innovation,employing data from China A-shared listed firms spanning the period 2.07 to *** measure corporate innovation from two perspectives:Input and ***,we use the ratio of research and development(R&D)expenditure to sales as a proxy for the innovation input and the number of patent citations excluding self-citations to measure innovation *** find that analyst coverage promotes corporate innovation,which is consistent with the“bright”side of analyst ***,the positive effect of analyst coverage hinges on effectively transmitting and disclosing accurate information to investors in the capital *** on this,analysts'forecasting bias includes forecasting dispersion and optimism *** find evidence that an increase in analysts'forecast dispersion leads to a decrease in corporate innovation ***,this paper presents a novel approach by employing the regression discontinuity method to examine the effect of analyst optimistic bias on firm *** empirical findings reveal that overly optimistic forecasts by analysts exacerbate innovation *** analyses enrich the research on analyst coverage and corporate innovation,providing an empirical basis for improving the capital market with the help of analysts.

关键词： analyst coverage forecasting bias corporate innovation innovation quality

Oral administration of egg white ovotransferrin prevents osteoporosis in ovariectomized rats

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Food Science and Human Wellness 2024年第5期13卷 2562-2572页

作者： Nan Shang Xiaoyu Bao Michael Doschak jianping Wu Department of Agricultural Food and Nutritional ScienceUniversity of AlbertaEdmonton T6G 2P5Canada College of Engineering China Agricultural UniversityBeijing 100083China Key Laboratory of Precision Nutrition and Food Quality Department of Nutrition and HealthyChina Agricultural UniversityBeijing 100193China Faculty of Pharmacy&Pharmaceutical Sciences University of AlbertaEdmonton T6G 2H5Canada

Ovotransferrin,an iron-binding glycoprotein,accounting for approximately 12.of egg white protein,is a member of transferrin fam *** previous studies showed that ovotransferrin stimulates the proliferation and differentiation of osteoblasts,while inhibits osteoclastogenesis and resorption *** work aims to study the efficacy of orally administered ovotransferrin on the prevention of osteoporosis using ovariectomized(OVX)Sprague-Dawley *** administration of ovotransferrin showed no negative effect on body weight,food intake and organ *** 12.week treatment,feeding ovotransferrin at a dose of 1%(1 g ovotransferrin/100 g diet)prevented OVX-induced bone loss and maintained relatively high bone mineral density and integrated bone *** serum concentration of biomarkers indicating bone formation was increased in ovotransferrin administration groups,while the bone resorption biomarkers were *** feeding also decreased the production of serum cytokine TNF-αand IL-6,which are two stimulators for osteoclast *** addition to its direct regulatory role on bone turnover,ovotransferrin supplementation might benefit osteoporosis prevention by inhibiting adipogenesis,and regulating immune *** results suggested the potential application of ovotransferrin as a functional food ingredient on the prevention of osteoporosis.

关键词： Ovotransferrin Ovariectomized(OVX)rats Bone mineral density Bone microarchitecture Bone resorption Inflammation

Attention,neighbors:Methyl salicylate mediates plant airborne defense

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Plant Communications 2024年第1期5卷 1-3页

作者： Shan Liu Faisal Islam jianping Chen Zongtao Sun Jian Chen International Genome Center Jiangsu UniversityZhenjiang 212013China State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products Key Laboratory of Biotechnology in Plant Protection of Ministry of Agriculture and Zhejiang ProvinceInstitute of Plant VirologyNingbo UniversityNingboChina

Plants have evolved to generate and release a wide array of volatile organic compounds(VOCs)when challenged by environmental stimuli such as biotic and abiotic stresses,which facilitate their reproduction,defense responses,and plant-plant communication(Karban,2.2.).Once emitted,some VOCs can elicit defense signaling in neighboring plants by interacting with specific receptor(s),a phenomenon referred to as airborne defense(AD)(Loreto and D’Auria,2.2.).

关键词： neighboring neighbor media

Acoustofluidic scanning fluorescence nanoscopy with a large field of view

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Microsystems & Nanoengineering 2024年第3期10卷 159-167页

作者： Geonsoo Jin Neil Upreti Joseph Rich jianping Xia Chenglong Zhao Tony Jun Huang Thomas Lord Department of Mechanical Engineering and Materials Science Duke UniversityDurhamNC 27708USA Department of Biomedical Engineering Duke UniversityDurhamNC 27708USA The MITRE Corporation McLeanVA 22102USA

Large-field nanoscale fluorescence imaging is invaluable for many applications,such as imaging subcellular structures,visualizing protein interactions,and high-resolution tissue ***,conventional fluorescence microscopy requires a trade-off between resolution and field of view due to the nature of the optics used to form the *** overcome this barrier,we developed an acoustofluidic scanning fluorescence nanoscope that simultaneously achieves superior resolution,a large field of view,and strong fluorescent *** acoustofluidic scanning fluorescence nanoscope utilizes the superresolution capabilities of microspheres that are controlled by a programmable acoustofluidic device for rapid fluorescence enhancement and *** acoustofluidic scanning fluorescence nanoscope resolves structures that cannot be resolved with conventional fluorescence microscopes with the same objective lens and enhances the fluorescent signal by a factor of~5 without altering the field of view of the *** improved resolution realized with enhanced fluorescent signals and the large field of view achieved via acoustofluidic scanning fluorescence nanoscopy provides a powerful tool for versatile nanoscale fluorescence imaging for researchers in the fields of medicine,biology,biophysics,and biomedical engineering.

关键词： field resolution utilize

Delineating homogeneous domains of fractured rocks using topological manifolds and deep learning

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 2996-3013页

作者： Yongqiang Liu jianping Chen Fujun Zhou Jiewei Zhan Wanglai Xu Jianhua Yan College of Construction Engineering Jilin UniversityChangchun130026China China Railway First Survey and Design Institute Group Co. Ltd.Xi’an710043China College of Geological Engineering and Geomatics Chang’an UniversityXi’an710054China

Determining homogeneous domains statistically is helpful for engineering geological modeling and rock mass stability *** this text,a technique that can integrate lithology,geotechnical and structural information is proposed to delineate homogeneous *** technique is then applied to a high and steep slope along a ***,geological and geotechnical domains were described based on lithology,faults,and shear ***,topological manifolds were used to eliminate the incompatibility between orientations and other parameters(*** length and roughness)so that the data concerning various properties of each discontinuity can be matched and characterized in the same Euclidean ***,the influence of implicit combined effect in between parameter sequences on the homogeneous domains could be *** learning technique was employed to quantify abstract features of the characterization images of discontinuity properties,and to assess the similarity of rock mass *** results show that the technique can effectively distinguish structural variations and outperform conventional *** can handle multisource engineering geological information and multiple discontinuity *** technique can also minimize the interference of human factors and delineate homogeneous domains based on orientations or multi-parameter with arbitrary distributions to satisfy different engineering requirements.

关键词： Homogeneous domain Geological domain Geotechnical domain Structural domain Topological manifold Deep learning