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A Newly Developed Non-Destructive Tritium Measurement Technique and Its Application to V-4Cr-4Ti Alloy

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Plasma Science and Technology 2006年第6期8卷 741-744页

作者：刘翔陈学 H.HOMMA y.HATANO M.matsuyama Southwestern Institute of Physics Chengdu 610041China Sichuan General Fire Brigade Chengdu 610072China Hydrogen Isotope Research Centre Toyama UniversityGofuku 3190Toyama 930-8555Japan

A non-destructive and in-situ technique for the measurement of tritium in materials, namely β-ray-induced X-ray spectrometry （BIXS）, has been developed recently. In the present study a V-4Cr-4Ti alloy was pre-heated at 1000℃ for 2 h to form a recrystallization structure before the tritium absorption experiments were conducted. Firstly the hydrogen isotope gas was charazterized by means of a quadrupole mass spectrometer （QMS） and a small-sized ionization chamber. Then hydrogen isotope absorption tests of V-4Cr-4Ti alloy were performed at 400 ℃ and the atomic concentration of hydrogen isotope in V-4Cr-4Ti alloy was estimated as 0.17% with a tritium content of approximately 2.5 ppm. Experimental results indicate that BIXS is a quite useful tool for quantitatively measuring the tritium content and tritium distribution in the surface layers of vanadium alloys and no strong trapping effects of tritium exist in the pre-heated V-4Cr-4Ti alloy.

关键词： tritium V-4Cr-4Ti β-ray-induced X-ray spectrometry tritium measurements

Influence of biomass burning on ozone levels in the Megalopolis of Central Mexico during the COVID-19 lockdown

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Journal of Environmental Sciences 2024年第9期143卷 99-115页

作者： Victor Almanza Luis Gerardo Ruiz-Suárez Ricardo Torres-Jardón Agustín García-Reynoso Iván y.Hernández-Paniagua Institute for Atmospheric Sciences and Climate Change National Autonomous University of MexicoCoyoacan 04510Mexico CityMexico

The massive reductions in anthropogenic emissions resulting from the COVID-19 lockdown provided a unique opportunity to evaluate the effect of mitigation measures aiming to abate air *** Mexico,the total lockdown period took place during the dry-hot season when biomass burning activity is ***,we investigate the role of biomass burning emissions on regional ozone levels in the Megalopolis of Central *** studied period covers the lockdown phases 2 and 3,and the first month of the New *** applied a factor separation technique and process analysis to estimate the pure and synergistic contributions of emission reductions under lockdown and that from biomass burning to daily ozone maximum concentrations in 7 metropolitan areas of different states in the *** results revealed that biomass burning plumes likely masked the effect of massive reductions from mobile emissions,impacted the PBL development during phase 3 and favored transition and mixed NO_(x)-limited and VOC-limited regional *** contributed to increased ozone production in the middle to lower PBL by changing the regional background levels which potentially could bias high ozone production efficiency *** the Megalopolis contribution to economic and societal development at national scale,our study suggests that ozone mitigation measures during the dry-hot season targeting mainly mobile emissions will likely be offset by biomass burning plumes.A regional and synergic policy aiming to control biomass burning would help to reduce the occurrence of high ozone levels in Central Mexico with the co-benefit of tackling short-lived climate pollutants.

关键词： COVID-19 Mexico Megalopolis Ozone Factor Separation Process Analysis

Selection criteria of MPOB-Angola germplasm collection for yield improvement of the oil palm

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Oil Crop Science 2024年第1期9卷 20-28页

作者： A.Norziha Z.Zamri y.Zulkifli A.M.Fadila M.Marhalil Malaysian Palm Oil Board 6Persiaran InstitusiBandar BaruBangi43000KajangSelangorMalaysia Institute of System Biology Universiti Kebangsaan Malaysia43600BangiSelangorMalaysia

Oil palm germplasm collected from Angola,Africa in 1991 were subjected to genetic variability potential *** collection was planted in the form of open-pollinated families as trials at the Malaysian Palm Oil Board(MPOB)Kluang Research Station,Johor,Malaysia,in *** palms from 52 families and tenera palms from 44 families of MPOB-Angola were evaluated for their bunch yield and bunch quality *** objectives of this study were to determine the genetic variability among the families and performance of MPOB-Angola germplasm for yield *** analysis of variance(ANOVA)revealed highly significant differences between the dura and tenera families for most of the traits,suggesting the presence of high genetic variability,which is essential for breeding *** the duras,family AGO 02.02 displayed the best yield performance,with a high fresh fruit bunch,oil yield and total economic product at 240.40,29.46 and 37.93 kg palm^(-1)year^(-1),*** for the teneras,family AGO 03.04 recorded the highest FFB yield and oil yield at 249.25 and 45.22 kg palm^(-1)year^(-1),*** that,several families with big fruit sizes or producing a mean fruit weight of 14-17 g were also *** dura and tenera from AGO 01.01 recorded the highest oil to bunch(O/B)of 17.76%and 28.65%,*** findings will facilitate the selection of palms from the MPOB-Angola germplasm for future breeding programmes.

关键词： Oil palm Germplasm Genetic variability Heritability yield improvement

PD-1^(+)and TIM-3^(+)T cells widely express commonγ-chain cytokine receptors in multiple myeloma patients,and IL-2,IL-7,IL-15 stimulation up-regulates PD-1 and TIM-3 on T cells

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Oncology Research 2024年第10期32卷 1575-1587页

作者： EGOR V.BATOROV ALISA D.INESHINA TATIANA A.ARISTOVA VERA V.DENISOVA SVETLANA A.SIZIKOVA DARIA S.BATOROVA GALINA y.USHAKOVA EKATERINA y.SHEVELA ELENA R.CHERNyKH Laboratory of Cellular Immunotherapy Research Institute of Fundamental and Clinical ImmunologyNovosibirsk630099Russia V.Zelman Institute of Medicine and Psychology Novosibirsk National Research State UniversityNovosibirsk630090Russia Department of Hematology and Bone Marrow Transplantation Research Institute of Fundamental and Clinical ImmunologyNovosibirsk630099Russia

Background:Immune checkpoint ligand-receptor interactions appear to be associated with multiple myeloma(MM)***,previous studies showed the possibility of PD-1 and TIM-3 expression on T cells upon stimulation with commonγ-chain family cytokines in vitro and during homeostatic *** aim of the present work was to study the impact of homeostatic proliferation on the expansion of certain T cell subsets upregulating PD-1 and TIM-3 checkpoint ***:The expression of CD25,CD122,CD127 commonγ-chain cytokine receptors,phosphorylated signal transducer and activator of transcription-5(pSTAT5)and eomesodermin(EOMES)was comparatively assessed with flow cytometry in PD-1-and TIM-3-negative and positive T cells before the conditioning and during the first post-transplant month in peripheral blood samples of MM ***:Substantial proportions of PD-1-and TIM-3-positive T lymphocytes expressed commonγ-chain cytokine receptors and *** of cytokine receptor expressing cells were significantly higher within TIM-3+T cells compared to PD-1+TIM-3−*** proportions of both PD-1-/TIM-3-negative and positive CD8+T cells express EOMES,while only moderate frequencies of CD4+PD-1+/TIM-3+T cells up-regulate this transcription ***,the surface presence of CD25 and intranuclear expression of EOMES in CD4+T cells were mutually exclusive regardless of PD-1 and TIM-3 *** stimulation with commonγ-chain cytokines up-regulates PD-1 and TIM-3 during the proliferation of initially PD-1/TIM-3-negative T cells but fails to expand initially PD-1+and TIM-3+T cell subsets in ***:Both PD-1 and TIM-3 expressing T cells appear to be able to respond to homeostatic cytokine *** in commonγ-chain cytokine receptor expression between PD-1+and TIM-3+T cells may reflect functional dissimilarity of these cell *** blockade appears to alleviate lymphopenia-induced prolif

关键词： Autologous hematopoietic stem cell transplantation(AHSCT) CD25 CD122 Eomesodermin(EOMES) Homeostatic proliferation

Towards an ultrafast 3D imaging scanning LiDAR system:a review

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Photonics Research 2024年第8期12卷 1709-1729页

作者： ZHI LI yAQI HAN LICAN WU ZIHAN ZANG MAOLIN DAI SZE yUN SET SHINJI yAMASHITA QIAN LI H.y.FU Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055China Department of Electrical Engineering and Information Systems The University of TokyoTokyo 113-8656Japan Research Center for Advanced Science and Technology The University of TokyoTokyo 153-8904Japan School of Electronic and Computer Engineering Peking UniversityShenzhen 518055China

Light detection and ranging(LiDAR),as a hot imaging technology in both industry and academia,has undergone rapid innovation and *** current mainstream direction is towards system miniaturization and *** are many metrics that can be used to evaluate the performance of a LiDAR system,such as lateral resolution,ranging accuracy,stability,size,and *** recently,with the continuous enrichment of LiDAR application scenarios,the pursuit of imaging speed has attracted tremendous research ***,for autonomous vehicles running on motorways or industrial automation applications,the imaging speed of LiDAR systems is a critical *** this review,we will focus on discussing the upper speed limit of the LiDAR *** on the working mechanism,the limitation of optical parts on the maximum imaging speed is *** beam scanner has the greatest impact on imaging *** provide the working principle of current popular beam scanners used in LiDAR systems and summarize the main constraints on the scanning ***,we highlight the spectral scanning LiDAR as a new paradigm of ultrafast ***,to further improve the imaging speed,we then review the parallel detection methods,which include multiple-detector schemes and multiplexing ***,we summarize the LiDAR systems with the fastest point acquisition rate reported *** the outlook,we address the current technical challenges for ultrafast LiDAR systems from different aspects and give a brief analysis of the feasibility of different approaches.

关键词： LiDAR scanner system

Effect of Eu^(3+),Bi^(3+),and Li^(+) doping on luminescent property of GdNbO_(4)

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Journal of Rare Earths 2024年第1期42卷 66-75,I0003页

作者： S.W.Wi y.S.Lee Department of Physics and Integrative Institute of Basic Sciences Soongsil UniversitySeoul06978Republic of Korea

We investigated the emission properties of Eu^(3+)-doped GdNbO_(4)-based oxide phosphors,aiming at improving the Eu^(3+)emission by codoping of Bi^(3+)and Li^(+).Eu^(3+)singly doped,Eu^(3+)and Bi^(3+)doubly doped,and Eu^(3+),Bi^(3+),and Li^(+)triply doped GdNbO_(4)were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu^(3+)in the singly doped samples are significantly improved by the codoping of Bi^(3+),mainly due to the energy transfer from Bi^(3+)to Eu^(3+).The additional codoping of Li^(+)is found to increase the Eu^(3+)emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu^(3+)in GdNbO_(4)does not change significantly with the codoping of Bi^(3+)and Li^(+).Our results indicate that Li^(+)doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO_(4)phosphors.

关键词： Eu^(3+) GdNbO_(4) Codoping of Li^(+) Photoluminescence Sensitizer Rare earths

Cortical hem signaling center: functions, development, and potential implications for evolution and brain disorders

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Neural Regeneration Research 2025年第4期20卷 1079-1080页

作者： Victor V.Chizhikov Igor y.Iskusnykh Department of Anatomy and Neurobiology University of Tennessee Health Science CenterMemphisTNUSA

Development of the telencephalon relies upon several signaling centers-localized cellular populations that supply secreted factors to pattern the cortical *** such signaling center is the cortical hem,which arises during embryonic development at the telencephalic dorsal midline,adjacent to the choroid plexus and hippocampal primordium(Figure 1A).While the cortical hem has also been described in reptiles and birds,most of our knowledge about the developmental roles of the cortical hem is derived from the analysis in *** cortical hem produces several types of secreted molecules,including wingless-related integration site(Wnt)and bone morphogenetic(Bmp)*** cortical hem is particularly important for the development of the hippocampus,which is involved in learning and memory,and the neocortex,which is the most complex brain region that mediates multiple types of behavior and higher cognitive functions(Mangale et al.,2008;Dal-Valle-Anton and Borrell,2022).

关键词： epithelium Figure center

Childhood opportunity and appropriate use of child safety restraints in motor vehicle collisions

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World Journal of Pediatric Surgery 2024年第2期7卷 142-149页

作者： Stephanie y Chen Iris Garcia Shadassa Ourshalimian Chantel Lowery Pradip P Chaudhari Ryan G Spurrier Pediatric Surgery Children's Hospital Los AngelesLos AngelesCaliforniaUSA Injury Prevention Program Children's Hospital Los AngelesLos AngelesCaliforniaUSA Emergency and Transport Medicine Children's Hospital Los AngelesLos AngelesCaliforniaUSA Pediatrics University of Southern California Keck School of MedicineLos AngelesCaliforniaUSA Surgery University of Southern California Keck School of MedicineLos AngelesCaliforniaUSA

Objectives Safety restraints reduce injuries from motor vehicle collisions(MVCs)but are often improperly applied or not *** Childhood Opportunity Index(COI)reflects social determinants of health and its study in pediatric trauma is *** hypothesized that MVC patients from low-opportunity neighborhoods are less likely to be appropriately *** A retrospective cross-sectional study was performed on children/adolescents≤18 years old in MVCs between January 1,2011 and December 31,*** were identified from the Children's Hospital Los Angeles trauma *** outcome was safety restraint use(appropriately restrained,not appropriately restrained).COI levels by home zip codes were stratified as very low,low,moderate,high,and very *** regression controlling for age identified factors associated with safety restraint *** Of 337 patients,73.9%were appropriately restrained and 26.1%were not appropriately *** with appropriately restrained patients,more not appropriately restrained patients were from low-COI(26.1%vs 20.9%),high-COI(14.8%vs 10.8%)and very high-COI(10.2%vs 3.6%)*** analysis demonstrated no significant associations in appropriate restraint use and *** was a non-significant trend that children/adolescents from moderate-COI neighborhoods were more likely than those from very low-COI neighborhoods to be appropriately restrained(OR=1.82,95%CI 0.78,4.28).Conclusion Injury prevention initiatives focused on safety restraints should target families of children from all neighborhood types.

关键词： MVC restrained neighborhood

Game Theory based Optimal Defensive Resources Allocation with Incomplete Information in Cyber-physical Power Systems against False Data Injection Attacks

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Protection and Control of Modern Power Systems 2024年第2期9卷 115-127页

作者： Bingjing yan Zhenze Jiang Pengchao yao Qiang yang Wei Li Albert y.Zomaya College of Electrical Engineering Zhejiang University College of Control Science and Engineering Zhejiang University College of Electrical Engineering Zhejiang UniversityHangzhou 310027China School of Information Technologies at The University of Sydney School of Information Technologies

Modern power grid is fast emerging as a complex cyber-physical power system(CPPS)integrating physical current-carrying components and processes with cyber-embedded computing,which faces increasing cy-berspace security threats and *** this paper,the state(i.e.,voltage)offsets resulting from false data injection(FDI)attacks and the bus safety characterization are applied to quantify the attack *** state offsets are obtained by the state estimation method,and the bus safety characterization considers the power net-work topology as well as the vulnerability and connection relationship of *** the indeterminacy of attacker’s resource consumption and reward,a zero-sum game-theoretical model from the defender’s perspective with incomplete information is explored for the optimal allocation of limited defensive *** attacker aims to falsify measurements without triggering threshold alarms to break through the protection,leading to load shedding,over-voltage or *** defender attempts to ensure the estimation results to be as close to the actual states as possible,and guarantee the system’s safety and efficient defensive resource *** proposed solution is extensively evaluated through simu-lations using the IEEE 33-bus test network and real-time digital simulator(RTDS)based testbed experiments of the IEEE 14-bus *** results demonstrate the effec-tiveness of the proposed game-theoretical approach for optimal defensive resource allocation in CPPS when lim-ited resources are available when under FDI *** Terms—Optimal strategy,game theory,Nash equilibrium,CPPS,FDI attack.

关键词： Optimal strategy game theory Nash equilibrium CPPS FDI attack