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An Approximation Algorithm Based on Seeding Algorithm for Fuzzy k-Means Problem with Penalties

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Journal of the Operations Research Society of China 2024年第2期12卷 387-409页

作者： wen-zhao Liu Min Li School of Mathematics and Statistics Shandong Normal UniversityJinan 250014ShandongChina

As a classic NP-hard problem in machine learning and computational geometry,the k-means problem aims to partition the given dataset into k clusters according to the minimal squared Euclidean *** from k-means problem and most of its variants,fuzzy k-means problem belongs to the soft clustering problem,where each given data point has relationship to every center *** to fuzzy k-means problem,fuzzy k-means problem with penalties allows that some data points need not be clustered instead of being paid *** this paper,we propose an O(αk In k)-approximation algorithm based on seeding algorithm for fuzzy k-means problem with penalties,whereαinvolves the ratio of the maximal penalty value to the minimal ***,we implement numerical experiments to show the effectiveness of our algorithm.

关键词： Approximation algorithm Seeding algorithm Fuzzy k-means problem with penalties

Giant panda(Ailuropoda melanoleuca)neonates use broadband calls to communicate with their mothers

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Integrative Zoology 2024年第2期19卷 277-287页

作者： Lin zhao Jianbin CHENG wen ZENG bo YANG Guiquan ZHANG Desheng LI Hemin ZHANG Christina DBUESCHING Dingzhen LIU Ministry of Education Key Laboratory of Biodiversity Science and Ecological EngineeringCollege of Life SciencesBeijing Normal UniversityBeijingChina Key Laboratory of State Forestry and Grassland Administration on Conservation Biology of Rare Animals in The Giant Panda National Park China Conservation and Research Center for the Giant PandaDujiangyanSichuan611830China Department of Biology Irving K.Barber Faculty of ScienceUniversity of British ColumbiaOkanaganKelownaBritish ColumbiaCanada

Infant call structure should have evolved to elicit maximum maternal attention and *** of giant pandas produce three types of vocalizations reported to be vitally important in the context of mother–infant ***,how cubs,0–15 days old,communicate with their mothers to elicit maternal care remains *** analyzed 12 different call parameters of 3475 squawks,1355 squalls,and 491 croaks from 11 captive giant panda(Ailuropoda melanoleuca)neonates from age 0 to 15 *** playback experiments,we also tested whether mothers could detect *** results show that neonates use broadband calls with ultrasonic frequencies up to 65 kHz to convey information about their physiological needs and to attract maternal *** playback experiments,we tested if mothers reacted differently to broadband calls(BBC)than to artificially altered calls that included only frequencies20 kHz(USC).Playback confirmed that,although adult females responded significantly less often to USC,BBC than to or AUDC,they could detect USC,BBC and generally made appropriate behavioral responses,indicating a potential benefit for neonates to utilize ultrasonic and broadband *** findings provide a new insight into mother–infant communication in giant pandas and will be helpful for reducing the mortality of cubs,younger than 1 month old,in captivity.

关键词： acoustic communication broadband calls maternal care neonates ultrasonic frequencies

Structure engineering of cathode host materials for Li-S batteries

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Rare Metals 2024年第4期43卷 1370-1389页

作者： Jia-Jun Long Hua Yu wen-bo Liu School of New Energy and Materials Southwest Petroleum UniversityChengdu610500China School of Mechanical Engineering Sichuan UniversityChengdu610065China

Although lithium-sulfur batteries are one of the favorable candidates for next-generation energy storage devices,a few key challenges that have not been addressed have limited its *** challenges include lithium dendrite growth in the anode side,volume change of the active material,poor electrical conductivity,dissolution and migration of poly sulfides,and slow rate of solid-state reactions in the cathode *** the electrochemical performance of lithium-sulfur batteries is greatly affected by the design of the cathode host material,it has also been widely discussed in addressing the abovementioned *** this paper,three design ideas of cathode host materials in terms of microstructure,crystal structure and electronic structure are introduced and ***,the current progress of these three structural design strategies and their effects on the electrochemical performance of lithium-sulfur batteries are discussed in ***,future directions in the structural design of cathode materials for lithium-sulfur batteries are discussed and further perspectives are provided.

关键词： Lithium-sulfur batteries Structure engineering Cathode Host materials

How plants sense and respond to osmotic stress

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Journal of Integrative Plant Biology 2024年第3期66卷 394-423页

作者： bo Yu Dai-Yin Chao Yang zhao Shanghai Center for Plant Stress Biology CAS Center for Excellence in Molecular Plant SciencesThe Chinese Academy of SciencesShanghai 200032China Key Laboratory of Plant Carbon Capture The Chinese Academy of SciencesShanghai 200032China National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyThe Chinese Academy of SciencesShanghai 200032China University of Chinese Academy of Sciences Beijing 100049China

Drought is one of the most serious abiotic stresses to land *** sense and respond to drought stress to survive under water *** have studied how plants sense drought stress,or osmotic stress caused by drought,ever since Charles Darwin,and gradually obtained clues about osmotic stress sensing and signaling in *** stress is a physical stimulus that triggers many physiological changes at the cellular level,including changes in turgor,cell wall stiffness and integrity,membrane tension,and cell fluid volume,and plants may sense some of these stimuli and trigger downstream *** this review,we emphasized water potential and movements in organisms,compared putative signal inputs in cell wall-containing and cell wall-free organisms,prospected how plants sense changes in turgor,membrane tension,and cell fluid volume under osmotic stress according to advances in plants,animals,yeasts,and bacteria,summarized multilevel biochemical and physiological signal outputs,such as plasma membrane nanodomain formation,membrane water permeability,root hydrotropism,root halotropism,Casparian strip and suberin lamellae,and finally proposed a hypothesis that osmotic stress responses are likely to be a cocktail of signaling mediated by multiple *** also discussed the core scientific questions,provided perspective about the future directions in this field,and highlighted the importance of robust and smart root systems and efficient source-sink allocations for generating future high-yield stress-resistant crops and plants.

关键词： cell volume drought membrane tension osmotic stress turgor

Short-term Association of Meteorological Elements on COVID-19 Pandemic in a Semi-arid City of Northwest China,2021-2022

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Biomedical and Environmental Sciences 2024年第5期37卷 537-542页

作者： FENG Feng Liu MA Yu Xia CHENG bo wen LIU Zong Rui zhao Yu Han YANG Jie College of Atmospheric Sciences Key Laboratory of Semi-Arid Climate ChangeMinistry of EducationLanzhou UniversityLanzhou 730000GansuChina Minhe Meteorological Bureau Minhe 810800QinghaiChina

The coronavirus disease 2019(COVID-19)outbreak in late 2019 significantly impacted global *** virus’s rapid spread,with its long incubation period and high infection level,caused substantial disruption to regular social frameworks,production,and lifestyles^([1]).COVID-19 is primarily transmitted through close contact,long-range contaminants,and airborne routes.

关键词： Northwest COV primarily

Study of the vibrational photochemical reation of UF_6+HCl and its isotopic selectivity

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Chinese Journal of Chemistry 1993年第2期11卷 97-104页

作者： XU,Bao-Yu LIU,Yong DONG,wen-bo zhao,Wei HU,Jian-Xun ZHENG,Cheng-Fa Nuclear Science Department,Fudan University,Shanghai 200433 Nuclear Science Department Fudan University Shanghai 200433

The photochemical vibrational reaction of UF_6+HCl was investigated by exciting the ternary overtone of 3ν_3 of UF_6 in an intracavity CO laser *** was found that the rate of the laser-driven reaction was much greater than that of the thermal reaction and this photochemical process had an isotopic *** uranium isotope enrichment factors measured in experiments wore around 1,007 in a single step.

关键词： Study of the vibrational photochemical reation of UF6+HCl and its isotopic selectivity UF HCl

A Cyclic Constitutive Model Based on Crystal Plasticity for body-Centered Cubic Cyclic Softening Metals

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Acta Mechanica Solida Sinica 2024年第1期37卷 33-42页

作者： Xuehong Ren wenjie zhao Shaopu Yang Guilin wen State Key Laboratory of Advanced Design and Manufacturing for Vehicle body Hunan UniversityChangsha 410082China School of Mechanical Engineering Tianjin Sino-German University of Applied SciencesTianjin 300350China State Key Laboratory of Mechanical Behavior in Traffic Engineering Structure and System Safety Shijiazhuang Tiedao UniversityShijiazhuang 050043China

Under the framework of the small deformation crystal plasticity theory,a crystal plastic cyclic constitutive model for body-centered cubic(BCC)cyclic softening polycrystalline metals is *** constitutive model introduces the isotropic softening rule that includes two different mechanisms:namely softening under monotonic deformation and softening under cyclic deformation on each slip ***,a modified Armstrong-Frederick nonlinear kinematic hardening rule is *** appropriate explicit scale transition rule is selected to extend the single crystal constitutive model to the polycrystalline constitutive *** the model is used to predict the uniaxial and multiaxial ratcheting deformation of BCC axle steel EA4T to verify the rationality of the proposed *** simulation results indicate that the newly established crystal plasticity model can not only describe the cyclic softening characteristics of BCC axle steel EA4T well,but also reasonably describe the evolution laws of uniaxial ratcheting and nonproportional multiaxial ratcheting ***,the established crystal plastic cyclic constitutive model can reasonably predict the ratcheting behavior of BCC single crystal as well.

关键词： Crystal plasticity Constitutive model Softening Ratcheting

Angiotensin-converting enzyme 2 alleviates liver fibrosis through the renin-angiotensin system

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World Journal of Gastroenterology 2024年第6期30卷 607-609页

作者： Bai-Wei zhao Ying-Jia Chen Ruo-Peng Zhang Yong-Ming Chen bo-wen Huang Department of Gastric Surgery Sun Yat-sen University Cancer CenterState Key Laboratory of Oncology in South ChinaGuangdong Provincial Clinical Research Center for CancerGuangzhou 510060Guangdong ProvinceChina Health Science Center Peking UniversityBeijing 100191China

The present letter to the editor is related to the study titled‘Angiotensin-converting enzyme 2 improves liver fibrosis in mice by regulating autophagy of hepatic stellate cells’.Angiotensin-converting enzyme 2 can alleviate liver fibrosis by regulating autophagy of hepatic stellate cells and affecting the renin-angiotensin system.

关键词： Angiotensin-converting enzyme 2 Hepatic stellate cells Liver fibrosis Angiotensin II Angiotensin 1-7 Renin-angiotensin system

Near-infrared carbon nanodots for effective identification and inactivation of Gram-positive bacteria

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Nano Research 2022年第3期15卷 1699-1708页

作者： wen-bo zhao Rui-Ting Wang Kai-Kai Liu Meng-Ru Du Yong Wang Yu-Qi Wang Rui Zhou Ya-Chuan Liang Ruo-Nan Ma Lai-Zhi Sui Qing Lou Lin Hou Chong-Xin Shan Henan Key Laboratory of Diamond Optoelectronic Materials and Devices Key Laboratory of Materials PhysicsMinistry of Educationand School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China School of Pharmaceutical Sciences Key Laboratory of Targeting Therapy and Diagnosis for Critical DiseasesCollaborative Innovation Center of New Drug Research and Safety EvaluationZhengzhou UniversityZhengzhou 450001China Henan Key Laboratory of Ion-beam Bioengineering School of Agricultural ScienceZhengzhou UniversityZhengzhou 450052China State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

An unacceptable increase in antibacterial resistance has arisen due to the abuse of multiple classes of broad-spectrum ***,it is significant to develop new antibacterial agents,especially those that can accurately identify and kill specific ***,we demonstrate a kind of perilla-derived carbon nanodots(CNDs),integrating intrinsic advantages of luminescence and photodynamic,providing the opportunity to accurately identify and kill specific *** CNDs have an exotic-doped andπ-conjugated core,vitalizing them near-infrared(NIR)absorption and emission properties with photoluminescence quantum yield of 21.1%;hydrophobic chains onto the surface of the CNDs make them to selectively stain Gram-positive bacteria by insertion into their *** to the strong absorption in NIR region,reactive oxygen species are in situ generated by the CNDs onto bacterial membranes under 660 nm irradiation,and 99.99%inactivation efficiency against Gram-positive bacteria within 5 min can be *** vivo results demonstrate that the CNDs with photodynamic antibacterial property can eliminate the inflammation of the area affected by methicillin-resistant Staphylococcus aureus(MRSA),and enabling the wound to be cured quickly.

关键词： carbon nanodots near-infrared emission specific identification anti-bacteria photodynamic therapy