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An improved algorithm for retrieving thin sea ice thickness in the Arctic Ocean from SMOS and SMAP L-band radiometer data

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Acta Oceanologica Sinica 2024年第3期43卷 127-138页

作者： Lian He Senwen Huang Fengming Hui Xiao Cheng School of Geospatial Engineering and Science Sun Yat-Sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Key Laboratory of comprehensive observation of Polar Environment(Sun Yat-Sen University) Ministry of EducationZhuhai 519082China

The aim of this study was to develop an improved thin sea ice thickness(SIT)retrieval algorithm in the Arctic Ocean from the Soil Moisture Ocean Salinity and Soil Moisture Active Passive L-band radiometer *** SIT retrieval algorithm was trained using the simulated SIT from the cumulative freezing degree days model during the freeze-up period over five carefully selected regions in the Beaufort,Chukchi,East Siberian,Laptev and Kara seas and utilized the microwave polarization ratio(PR)at incidence angle of 40°.The improvements of the proposed retrieval algorithm include the correction for the sea ice concentration impact,reliable reference SIT data over different representative regions of the Arctic Ocean and the utilization of microwave polarization ratio that is independent of ice *** relationship between the SIT and PR was found to be almost stable across the five selected *** SIT retrievals were then compared to other two existing algorithms(i.e.,UH_SIT from the University of Hamburg and UB_SIT from the University of Bremen)and validated against independent SIT data obtained from moored upward looking sonars(ULS)and airborne electromagnetic(EM)induction *** results suggest that the proposed algorithm could achieve comparable accuracies to UH_SIT and UB_SIT with root mean square error(RMSE)being about 0.20 m when validating using ULS SIT data and outperformed the UH_SIT and UB_SIT with RMSE being about 0.21 m when validatng using EM SIT *** proposed algorithm can be used for thin sea ice thickness(<1.0 m)estimation in the Arctic Ocean and requires less auxiliary data in the SIT retrieval procedure which makes its implementation more practical.

关键词： Arctic sea ice sea ice thickness remote sensing Soil Moisture Active Passive(SMAP) Soil Moisture Ocean Salinity and Soil(SMOS)

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Feasibility Study on Recovering Human-Occupied Vehicle with An Offshore Crane

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China Ocean Engineering 2024年第4期38卷 648-662页

作者： HAN Ming-yue XIE Peng XIAN Hao-yi ZHONG Xin-xin CHEN Sheng-lin SUN Tie-rui SUN Feng-lei School of Ocean Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China Key Laboratory of comprehensive observation of Polar Environment(Sun Yat-sen University) Ministry of EducationZhuhai 519082China Guangzhou Marine Engineering Corporation Guangzhou 510250China

Launching and recovering human-occupied vehicles(HOVs)has always been a challenging *** current recovery process requires staff to manually complete the tethering task,which is inefficient and endangers the lives of *** paper suggests moving the recovery position from the surface to underwater at approximately half the wavelength of the water depth(30−50 m underwater),where the HOV experiences less environmental *** ROV equipped with a ultra-short baseline beacon(USBL)and a manipulator was used to complete the tethering ***,a shackle customized to the shape of the manipulator’s gripper is fitted to the end of the cable to simplify the tethering *** investigate the dynamic response of recovering the HOV using this suggested method,a comprehensive numerical model is developed in this *** effects of wind,surface waves,ocean currents,and nonlinear interaction between the installation vessel and the HOV are quantitatively *** results show that the proposed recovery method can reduce the motion amplitude of the HOV and that the wave has the greatest influence on the dynamic response of the HOV during the recovery *** model provides better insight into the proposed HOV recovery method and confirms the effectiveness of the heave compensation *** proposed approach aims to enhance safety and operational efficiency by reducing direct human involvement in the recovery process and mitigating potential *** finding holds particular significance,especially in environmentally sensitive areas,where reducing the impact on the surrounding ecosystem is crucial.

关键词： human-occupied vehicle recovery dynamic response active heave compensation

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Homeostatic regulation of NAD(H)and NADP(H)in cells

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Genes & Diseases 2024年第5期11卷 285-299页

作者： Luojun Chen Xiaoke Xing Pingfeng Zhang Lulu Chen Huadong Pei Cancer center Renmin Hospital of Wuhan UniversityWuhanHubei 430062China Department of Oncology Georgetown Lombardi Comprehensive Cancer CenterGeorgetown University Medical CenterWashingtonDC 20057USA

Nicotinamide adenine dinucleotide(NAD^(+))/reduced NAD^(+)(NADH)and nicotinamide adenine dinucleotide phosphate(NADP^(+))/reduced NADP^(+)(NADPH)are essential metabolites involved in multiple metabolic pathways and cellular ***^(+)and NADH redox couple plays a vital role in catabolic redox reactions,while NADPH is crucial for cellular anabolism and antioxidant *** NAD(H)and NADP(H)homeostasis is crucial for normal physiological activity and is tightly regulated through various mechanisms,such as biosynthesis,consumption,recycling,and conversion between NAD(H)and NADP(H).The conversions between NAD(H)and NADP(H)are controlled by NAD kinases(NADKs)and NADP(H)phosphatases[specifically,metazoan SpoT homolog-1(MESH1)and nocturnin(NOCT)].NADKs facilitate the synthesis of NADP^(+)from NAD^(+),while MESH1 and NOCT convert NADP(H)into NAD(H).In this review,we summarize the physiological roles of NAD(H)and NADP(H)and discuss the regulatory mechanisms governing NAD(H)and NADP(H)homeostasis in three key aspects:the transcriptional and posttranslational regulation of NADKs,the role of MESH1 and NOCT in maintaining NAD(H)and NADP(H)homeostasis,and the influence of the circadian clock on NAD(H)and NADP(H)*** conclusion,NADKs,MESH1,and NOCT are integral to various cellular processes,regulating NAD(H)and NADP(H)*** of these enzymes results in various human diseases,such as cancers and metabolic ***,strategies aiming to restore NAD(H)and NADP(H)homeostasis hold promise as novel therapeutic approaches for these diseases.

关键词： MESH1 NAD(H) NADK NADP(H) Nocturnin

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Fantastic voyage: The journey of NLRP3 inflammasome activation

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Genes & Diseases 2024年第2期11卷 819-829页

作者： Xiangyong Que Sihao Zheng Qibin Song Huadong Pei Pingfeng Zhang Cancer center Renmin Hospital of Wuhan UniversityWuhanHubei 430060China Department of Oncology Georgetown Lombardi Comprehensive Cancer CenterGeorgetown University Medical CenterWashingtonDC 20057USA

NLRP3 inflammasome,an intracellular multiprotein complex,can be activated by a range of pathogenic microbes or endogenous hazardous *** activation results in the release of cytokines such as IL-1β and IL-18,as well as Gasdermin D which eventually causes *** activation of NLRP3 inflammasome is under strict control and regulation by numerous pathways and *** excessive activation can lead to a persistent inflammatory response,which is linked to the onset and progression of severe *** studies have revealed that the subcellular localization of NLRP3 changes significantly during the activation *** this review,we review the current understanding of the molecular mechanism of NLRP3 inflammasome activation,focusing on the subcellular localization of NLRP3 and the associated regulatory *** aim to provide a comprehensive understanding of the dynamic transportation,activation,and degradation processes of NLRP3.

关键词： Inflammasome activation Innate immunity NLRP3 NLRP3 inflammasome Subcellular localization

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Molecular compositions and sources of organic aerosols at a rural site on the Guanzhong Plain,Northwest China:The importance of biomass burning

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Particuology 2024年第6期89卷 44-56页

作者： Yali Liu Minxia Shen Haijiao Liu Wenting Dai Weining Qi Yifan Zhang Lu Li Yue Cao Xin Wang Xiao Guo Yingkun Jiang Jianjun Li State Key Laboratory of Loess and Quaternary Geology Key Lab of Aerosol Chemistry and PhysicsInstitute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China Xi'an Institute for Innovative Earth Environment Research Xi'an 710061China National observation and Research Station of Regional Ecological Environment Change and comprehensive Management in the Guanzhong Plain ShaanxiChina

The concentration of PM_(2.5)has considerably reduced in recent years,but remains relatively high in *** particular,the increasing contribution of organic compounds to PM_(2.5)generates popular pressure for further reductions,resulting in an urgent need to study organic aerosol(OA).To investigate the molecular composition and source contribution of OA in the rural area of the Guanzhong Plain,Northwest China,PM_(2.5)samples were collected during 3–23 August 2016 and 5–20 January 2017 and studied for more than 100 organic tracer *** mean concentration of total measured organic compounds is 662±296 ng/m^(3)in summer and 3258±1925 ng/m^(3)in *** is the most abundant single compound found throughout the sampling period,which is a crucial tracer for biomass burning emissions,preliminary suggesting that biomass burning is an essential source of *** summer,organic compounds such as lipid compounds,sugar compounds,and polycyclic aromatic hydrocarbons(PAHs),more come from higher plants,wood burning,vehicle exhausts,plastic waste,and other direct emission *** PAHs(OPAHs),nitrophenols,and phthalic acids more come from the atmosphere through the oxidation reaction of aromatic precursors,especially photochemical ***,in winter,most of the increases in concentrations of organic compounds are attributed to biomass *** analysis of a haze event(14–19 January 2017)during the winter sampling period shows that the increases in the concentration of organic compounds are unaccompanied by strong secondary formation under lower relative humidity(49.1%±13.5%).The main reason for the growth of OA in this haze event is the accumulation of primary OA(POA).The source apportionment by the positive matrix factorization(PMF)model shows that biomass burning(37.1%)is the primary source of OA in the rural regions of the Guanzhong Plain,especially in winter(40.6%).The contribution of secondary formation decreases from 26.0%in summer t

关键词： Organic aerosol Molecular composition Seasonal variation Source apportionment Guanzhong Plain

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Hybrid-Vlasov simulation of soft X-ray emissions at the Earth’s dayside magnetospheric boundaries

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Earth and Planetary Physics 2024年第1期8卷 70-88页

作者： M.Grandin H.K.Connor S.Hoilijoki M.Battarbee Y.Pfau-Kempf U.Ganse K.Papadakis M.Palmroth Department of Physics University of HelsinkiHelsinkiFinland NASA Goddard Space Flight center GreenbeltMD20771USA Space and Earth observation Centre Finnish Meteorological InstituteHelsinkiFinland

Solar wind charge exchange produces emissions in the soft X-ray energy range which can enable the study of near-Earth space regions such as the magnetopause,the magnetosheath and the polar cusps by remote sensing *** Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)and Lunar Environment heliospheric X-ray Imager(LEXI)missions aim to obtain soft Xray images of near-Earth space thanks to their Soft X-ray Imager(SXI)*** earlier modeling works have already simulated soft X-ray images as might be obtained by SMILE SXI during its mission,the numerical models used so far are all based on the magnetohydrodynamics description of the space *** investigate the possible signatures of ion-kinetic-scale processes in soft Xray images,we use for the first time a global hybrid-Vlasov simulation of the geospace from the Vlasiator *** simulation is driven by fast and tenuous solar wind conditions and purely southward interplanetary magnetic *** first produce global X-ray images of the dayside near-Earth space by placing a virtual imaging satellite at two different locations,providing meridional and equatorial *** then analyze regional features present in the images and show that they correspond to signatures in soft X-ray emissions of mirrormode wave structures in the magnetosheath and flux transfer events(FTEs)at the *** results suggest that,although the time scales associated with the motion of those transient phenomena will likely be significantly smaller than the integration time of the SMILE and LEXI imagers,mirror-mode structures and FTEs can cumulatively produce detectable signatures in the soft X-ray *** instance,a local increase by 30%in the proton density at the dayside magnetopause resulting from the transit of multiple FTEs leads to a 12%enhancement in the line-of-sight-and time-integrated soft X-ray emissivity originating from this ***,a proton density increase by 14%in the magnetosheath

关键词： magnetosphere magnetosheath numerical simulation SMILE LEXI soft X-ray emissions hybrid-Vlasov model polar cusp flux transfer events mirror-mode waves

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Joint Sample Position Based Noise Filtering and Mean Shift Clustering for Imbalanced Classification Learning

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Tsinghua Science and Technology 2024年第1期29卷 216-231页

作者： Lilong Duan Wei Xue Jun Huang Xiao Zheng School of Computer Science and Technology Anhui University of TechnologyMaanshan 243032China Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230088China

The problem of imbalanced data classification learning has received much *** classification algorithms are susceptible to data skew to favor majority samples and ignore minority *** weighted minority oversampling technique(MWMOTE)is an effective approach to solve this problem,however,it may suffer from the shortcomings of inadequate noise filtering and synthesizing the same samples as the original minority *** this end,we propose an improved MWMOTE method named joint sample position based noise filtering and mean shift clustering(SPMSC)to solve these ***,in order to effectively eliminate the effect of noisy samples,SPMsC uses a new noise filtering mechanism to determine whether a minority sample is noisy or not based on its position and distribution relative to the majority *** that MWMOTE may generate duplicate samples,we then employ the mean shift algorithm to cluster minority samples to reduce synthetic replicate ***,data cleaning is performed on the processed data to further eliminate class *** on extensive benchmark datasets demonstrate the effectiveness of SPMsC compared with other sampling methods.

关键词： imbalanced data classification oversampling noise filtering clustering

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CD8+T cell metabolic flexibility elicited by CD28-ARS2 axisdriven alternative splicing of PKM supports antitumor immunity

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Cellular & Molecular Immunology 2024年第3期21卷 260-274页

作者： G.Aaron Holling Colin A.Chavel Anand P.Sharda Mackenzie M.Lieberman Caitlin M.James Shivana M.Lightman Jason H.Tong Guanxi Qiao Tiffany R.Emmons Thejaswini Giridharan Shengqi Hou Andrew M.Intlekofer Richard M.Higashi Teresa W.M.Fan Andrew N.Lane Kevin H.Eng Brahm H.Segal Elizabeth A.Repasky Kelvin P.Lee Scott H.Olejniczak Department of Immunology Roswell Park Comprehensive Cancer CenterBuffaloNY 14263USA Department of Medicine Roswell Park Comprehensive Cancer CenterBuffaloNY 14263USA Human Oncology and Pathogenesis Program Memorial Sloan Kettering Cancer CenterNew YorkNY 10065USA center for Environmental Systems Biochemistry Department of Toxicology and Cancer Biology and Markey Cancer CenterLexingtonKY 40536USA Department of Cancer Genetics and Genomics Roswell Park Comprehensive Cancer CenterBuffaloNY 14263USA Present address:University of Colorado Boulder BoulderCO 80309USA Present address:Dana Farber Cancer Institute BostonMA 02215USA Present address:Massachusetts Institute of Technology BostonMA 02139USA Present address:Melvin and Bren Simon comprehensive Cancer center Indiana University School of MedicineIndianapolisIN 46202USA

Metabolic flexibility has emerged as a critical determinant of CD8+T-cell antitumor activity,yet the mechanisms driving the metabolic flexibility of T cells have not been *** this study,we investigated the influence of the nuclear cap-binding complex(CBC)adaptor protein ARS2 on mature T *** doing so,we discovered a novel signaling axis that endows activated CD8+T cells with flexibility of glucose ***2 upregulation driven by CD28 signaling reinforced splicing factor recruitment to pre-mRNAs and affected approximately one-third of T-cell activation-induced alternative splicing *** these effects,the CD28-ARS2 axis suppressed the expression of the M1 isoform of pyruvate kinase in favor of PKM2,a key determinant of CD8+T-cell glucose utilization,interferon gamma production,and antitumor effector ***,PKM alternative splicing occurred independently of CD28-driven PI3K pathway activation,revealing a novel means by which costimulation reprograms glucose metabolism in CD8+T cells.

关键词： Immunometabolism mRNA splicing CD8 T cells ARS2 PKM2

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Spectral Fittings of Warm Coronal Radiation with High Seed Photon Temperature: Apparent Low-temperature and Flat Soft Excess in AGNs

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Research in Astronomy and Astrophysics 2024年第7期24卷 138-147页

作者： Ze-Yuan Tang Jun-Jie Feng Jun-Hui Fan School of Mathematics and Information Science Guangzhou University center for Astrophysics Guangzhou University Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province Key Laboratory for Astronomical observation and Technology of Guangzhou

A warm corona has been widely proposed to explain the soft excess （SE） in X-ray above the 2–10 ke V power law extrapolation in Active Galactic Nuclei （AGNs）.In actual spectral fittings,the warm coronal seed photon temperature（Ts） is usually assumed to be far away from the soft X-ray,but kTscan reach close to 0.1 ke V in the standard accretion disk *** this study,we used Monte Carlo simulations to obtain radiation spectra from a slab-like warm corona and fitted the spectra using the spherical-geometry-based routine THCOMP or a thermal *** findings reveal tha high Tscan influence the fitting results.A moderately high kTs（around 0.03 ke V） can result in an apparent low-temperature and flat SE,while an extremely high kTs（around 0.07 ke V） can even produce an unobserved blackbody-like *** conclusions indicate that,for spectral fittings of the warm coronal radiation （SE in AGNs）,kTsshould be treated as a free parameter with an upper limit,and an accurate coronal geometry is necessary when kTs>0.01 ke V.

关键词： accretion accretion disks black hole physics galaxies: active

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Physics-embedded machine learning search for Sm-doped PMN-PT piezoelectric ceramics with high performance

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Chinese Physics B 2024年第8期33卷 81-88页

作者：辛睿王亚祺房泽郑凤基高雯付大石史国庆刘建一张永成 College of Physics Center for Marine Observation and CommunicationsNational Demonstration Center for Experimental Applied Physics EducationQingdao UniversityQingdao 266071China Centre for Theoretical and Computational Physics College of PhysicsQingdao UniversityQingdao 266071China

Pb(Mg_(1/3)Nb_(2/3))O_(3)–PbTiO_(3)(PMN-PT)piezoelectric ceramics have excellent piezoelectric properties and are used in a wide range of *** the solid solution ratios of PMN/PT and different concentrations of elemental doping are the main methods to modulate their piezoelectric *** combination of these controllable conditions leads to an exponential increase of possible compositions in ceramics,which makes it not easy to extend the sample data by additional experimental or theoretical *** this paper,a physics-embedded machine learning method is proposed to overcome the difficulties in obtaining piezoelectric coefficients and Curie temperatures of Sm-doped PMN-PT ceramics with different *** contrast to all-data-driven model,physics-embedded machine learning is able to learn nonlinear variation rules based on small datasets through potential correlation between ferroelectric *** on the model outputs,the positions of morphotropic phase boundary(MPB)with different Sm doping amounts are *** also find the components with the best piezoelectric property and comprehensive ***,we set up a database according to the obtained results,through which we can quickly find the optimal components of Sm-doped PMN-PT ceramics according to our specific needs.

关键词： Pb(Mg_(1/3)Nb_(2/3))O_(3)–PbTiO_(3)(PMN-PT)ceramic physics-embedded machine learning piezoelectric coefficient Curie temperature

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