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Plasma Science and Technology 2007年第6期9卷 740-742页

作者： Y.SHIMADA M.YAMAURA c.yamanaka Institute for Laser Technology OsakaJapan

A study to generate longer plasma channel was conucted to improve probability of triggered lightning. To generate the long laser plasma channel, a strongly and a weakly ionized plasma channels were used in series, a scheme called hybrid method. The strongly and the weakly ionized plasma channels were used for triggering an electrical leader and guiding the leader. The electrical leader propagated through the weakly ionized plasma. Then main discharge occurred between the electrodes. It is found that the streamer was accelerated with both the increase in the plasma density and the increase in an ambient electric field close to the plane electrode.

关键词： laser plasma channel lightning velocity of streamer

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日本激光聚变计划概况

激光 1980年第Z1期 19-19页

作者： c.yamanaka 日本大阪大学

本文介绍了日本激光聚变计划的概况,以及为达到惯性约束聚变的科学现实性,利用Ge-

关键词：激光聚变激光核聚变聚变反应日本

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未来气候条件下蒙古草原植被的预测分布

Journal of Plant Ecology 2024年第3期17卷 16-27页

作者： Kohei Suzuki Ikutaro Tsuyama Radnaakhand Tungalag Amartuvshin Narantsetseg Tsagaanbandi Tsendeekhuu Masato Shinoda Norikazu yamanaka Takashi Kamijo Department of Regional Regeneration Science Faculty of Regional Environment ScienceTokyo University of AgricultureTokyo 156-8502Japan Hokkaido Research center Forestry and Forest Products Research InstituteHokkaido 062-8516Japan Department ofBiology School of Arts and SciencesNational University of MongoliaUlaanbaatar 210646Mongolia Botanic Garden and ResearchInstitute Mongolian Academy of ScienceUlaanbaatar 51Mongolia Department of Earth and Environmental Sciences GraduateSchool of Environmental StudiesNagoya UniversityNagoya 464-8601Japan Arid Land Research center Tottori UniversityTottori680-0001Japan Faculty of Life and Environmental Sciences University of TsukubaIbaraki 305-8572Japan

蒙古牧民家庭通过适应当地植被分布的特点来维持牲畜的健康状况。因此,预测未来植被变化对于稳定的牲畜放牧和可持续的草原利用至关重要。本研究基于前期研究获得的植被数据预测了2081年至2100年间草原植被,尤其是沙漠草原、草原和草甸... 详细信息

蒙古牧民家庭通过适应当地植被分布的特点来维持牲畜的健康状况。因此,预测未来植被变化对于稳定的牲畜放牧和可持续的草原利用至关重要。本研究基于前期研究获得的植被数据预测了2081年至2100年间草原植被,尤其是沙漠草原、草原和草甸草原的分布范围。我们首先基于在蒙古(43–50°N,87–119°E)收集的草原植被数据(2012至2016年,278个样地)划分了不同的群落类型。其次,采用最大熵(MaxEnt)模型进行物种分布建模,其中以荒漠草原、草原和草甸草原的分布数据作为目标变量,使用Worldclim的生物气候数据作为解释变量。最后,采用Worldclim提供的cMIP6下缩放的未来气候预测数据进行未来预测。结果发现,荒漠草原、草原和草甸草原模型的曲线下面积值分别为0.850、0.847和0.873。根据所有情景和所有群落的气候变化,适宜栖息地预计将缩小。潜在适宜区域减少的程度在草甸草原群落中最为显著。上述结果表明,未来气候变化情景下草甸草原群落将转变为草原群落。

关键词：气候变化群落最大熵物种分布建模草原 Worldclim

Important step towards an understanding of the exotic Z_(c)(3900)

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Science china(Physics,Mechanics & Astronomy) 2024年第9期67卷 199-200页

作者： c.Hanhart Institute for Advanced Simulation Forschungszentrum JulichJilich D-52425Germany

The Standard Model of particle physics,which contains the field theories for the electro-weak interaction(QED)and the strong interaction(QcD),is an extremely successful theory describing a huge variety of phenomena at... 详细信息

关键词： interaction atomic describing

Light sheet microscope scanning of biointegrated microlasers for localized refractive index sensing

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Photonics Research 2024年第8期12卷 1673-1680页

作者： ROSS c.cOWIE MARcEL ScHUBERT SUPA School of Physics and AstronomyUniversity of St AndrewsSt AndrewsUK Humboldt centre for Nano and Biophotonics Department of ChemistryUniversity of CologneCologneGermany

Whispering gallery mode(WGM)microlasers are highly sensitive to localized refractive index changes allowing to link their emission spectrum to various chemical,mechanical,or physical *** recently found applications in biological studies within single cells,in three-dimensional samples such as multicellular spheroids,or in ***,detailed studies of biological samples also need to account for the structural heterogeneity of tissues and live animals,therefore requiring a combination of high-resolution microscopy and laser ***,we design and construct a light sheet fluorescence microscope with a coupled spectrometer for use in microlaser studies for combined high-resolution,high-speed imaging and WGM spectral *** light sheet illumination profile and the decoupled geometry of excitation and emission hereby directly affect the lasing and sensing properties,mainly through geometric constraints and by light coupling *** demonstrate the basic working principle of microlaser spectroscopy under light sheet excitation and measure the absolute refractive index within agarose and in zebrafish tail muscle *** further analyze the light coupling conditions that lead to the occurrence of two separate oscillation *** so-called cross modes can be scanned around the entire microlaser surface,which allows to estimate a surface-averaged refractive index profile of the microlaser environment.

关键词： refractive index excitation

A toast to a zebrafish germ cell induction cocktail

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Science china(Life Sciences) 2024年第6期67卷 1314-1315页

作者： Mary c.Mullins Department of cell and Developmental Biology University of Pennsylvania Perelman School of MedicinePhiladelphia 19104USA

The zebrafish field is ringing in the new year with a publication from Yonghua Sun's laboratory(Wang et al.,2023)of a cocktail of germline factors that can induce all cells of the zebrafish embryo into primordial germ cells(PGcs)at phenomenal *** major advance is not only of great interest to germ cell biologists,but it has important applications to the entire zebrafish field,as shown in Wang et al.(2023).

关键词： fish zebra field

convergence,Scalarization and continuity of Minimal Solutions in Set Optimization

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Journal of the Operations Research Society of china 2024年第3期12卷 773-793页

作者： Karuna c.S.Lalitha Department of Mathematics University of DelhiDelhiDelhi110007India Department of Mathematics University of Delhi South CampusNew DelhiDelhi110021India

The paper deals with the study of two different aspects of stability in the given space as well as the image space,where the solution concepts are based on a partial order relation on the family of bounded subsets of a real normed linear *** first aspect of stability deals with the topological set convergence of families of solution sets of perturbed problems in the image space and Painlevé–Kuratowski set convergence of solution sets of the perturbed problems in the given *** convergence in the given space is also established in terms of solution sets of scalarized perturbed *** second aspect of stability deals with semicontinuity of the solution set maps of parametric perturbed problems in both the spaces.

关键词： Topological convergence Painlevé-Kuratowski convergence Upper semicontinuity Lower semicontinuity Stability Scalarization

Performance of evolutionary optimized machine learning for modeling total organic carbon in core samples of shale gas fields

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Petroleum 2024年第1期10卷 150-164页

作者： Leonardo Goliatt c.M.Saporetti L.c.Oliveira E.Pereira Department of computational and Applied Mechanics Federal University of Juiz de ForaJuiz de ForaBrazil Department of computational Modeling Polytechnic InstituteRio de Janeiro State UniversityNova FriburgoBrazil Petrobras Rio de JaneiroBrazil Department of Stratigraphy and Paleontology Rio de Janeiro State UniversityRio de JaneiroBrazil

Rock samples'TOc content is the best indicator of the organic matter in source *** origin rock samples’analysis is used to calculate it manually by *** method requires time and resources because it relies on samples from many well intervals in source ***,research has been done to aid this *** learning algorithms can estimate total organic carbon instead of well logs and stratigraphic *** light of these efforts,the current work present a study on automating the total organic carbon estimation using machine learning approaches improved by an evolutionary methodology to give the model flexibility and *** algorithms,differential evolution,particle swarm optimization,grey wolf optimization,artificial bee colony,and evolution strategies were used to improve machine learning models to predict *** six metaheuristics were integrated into four machine learning methods:extreme learning machine,elastic net linear model,linear support vector regression,and multivariate adaptive regression *** samples from the YuDong-Nan shale gas field,located in the Sichuan basin,were used to evaluate the hybrid *** findings show that combining machine learning models with an evolutionary algorithms in a hybrid fashion produce flexible models that accurately predict *** results show that,independent of the metaheuristic used to guide the model selection,optimized extreme learning machines attained the best performance scores according to six *** hybrid models can be used in exploratory geological research,particularly for unconventional oil and gas resources.

关键词： Total organic carbon Hybrid models Automated machine learning Evolutionary algorithms Geology

A perspective on utilizing the minority stress model for HIV and mental health care for men who have sex with men

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Asian Pacific Journal of Tropical Medicine 2024年第8期17卷 333-334页

作者： Rowalt c.Alibudbud Department of Sociology and Behavioral Sciences De La Salle UniversityManilaPhilippines

In 2022,the Joint United Nations Programme on HIV/AIDS(UNAIDS)and the World Health Organization(WHO)called upon global,regional,national,and local stakeholders to embrace a holistic approach to person-centered HIV prevention,treatment,and care[1].This approach emphasizes integrating mental health and psychosocial support services into existing frameworks[1].It recognizes the critical role these services play in addressing mental distress and improving the overall well-being and quality of life for people living with HIV[1].In light of men who have sex with men(MSM)remaining a key population affected by HIV[1],it becomes imperative to delve into the shared factors that influence their HIV care and mental health,among which minority stress stands out as a critical consideration.

关键词： prevention distress stress

Exercise immunology:Novel insights

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Journal of Sport and Health Science 2024年第3期13卷 277-279,I0001页

作者： David c.Nieman Human Performance Laboratory Appalachian State UniversityNorth Carolina Research CampusKannapolisNC 28081USA

The coronavirus disease 2019(cOVID-19)pandemic heightened worldwide attention on the influence of exercise on the immune *** were raised about whether regular moderate-to-vigorous physical activity(MVPA)could help prevent cOVID-19 or mitigate symptoms when *** MVPA bolster immunity among those most prone to cOVID-19 including the elderly,obese,and immunocompromised patients?Does regular MVPA dampen systemic inflammation,thereby lessening the cOVID-19 cytokine storm?

关键词： immunity inflammation thereby