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Detector performance of the gamma-ray Transient Monitor onboard DRO-A satellite

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Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 75-90页

作者： Pei-Yi Feng Zheng-hua An Da-Li Zhang Chen-Wei Wang Chao Zheng Sheng ya.g Shao-Lin Xiong Jia-Cong Liu Xin-Qiao Li Ke gong Xiao-Jing Liu Min gao Xiang-ya.g Wen ya.Qing Liu Xiao-Yun Zhao Fan Zhang Xi-Lei Sun Hong Lu Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

The gamma-ray Transient Monitor(gTM) is an all-sky monitor onboard the Distant Retrograde Orbit-A(DRO-A) satellite with the scientific objective of detecting gamma-ray transients ranging from 20 ke V to 1 MeV. The gTM was equipped with five gamma-ray Transient Probe(gTP) detector modules utilizing a NaI(Tl) scintillator coupled with a SiPM array. To reduce the SiPM noise, gTP uses a dedicated dual-channel coincident readout design. In this work, we first studied the impact of different coincidence times on the detection efficiency and ultimately selected a 0.5 μs time coincidence window for offline data processing. To test the performance of the gTPs and validate the Monte-Carlo-simulated energy response, we conducted comprehensive ground calibration tests using the Hard X-ray Calibration Facility(HXCF) and radioactive sources, including the energy response, detection efficiency, spatial response, bias-voltage response, and temperature dependence. We extensively present the ground calibration results and validate the design and mass model of the gTP detector, thus providing the foundation for in-flight observations and scientific data analysis.

关键词： NaI(Tl)detector energy response ground calibration gamma-ray detector DRO-A satellite

“非粮化”治理视角下的耕地用途管制:应对逻辑与体系构建

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自然资源学报 2024年第4期39卷 942-959页

作者：袁源王亚华徐萍河海大学公共管理学院南京211100 南京师范大学地理科学学院南京210034

保障国家粮食安全的根本在耕地。在国土空间用途管制的大背景下,对耕地数量的单一管控已转向落实“藏粮于地”战略,“大食物观”也赋予粮食安全新的内涵,“非粮化”治理亟需探索新时期耕地用途管制的应对逻辑并构建理论框架体系。通过... 详细信息

保障国家粮食安全的根本在耕地。在国土空间用途管制的大背景下,对耕地数量的单一管控已转向落实“藏粮于地”战略,“大食物观”也赋予粮食安全新的内涵,“非粮化”治理亟需探索新时期耕地用途管制的应对逻辑并构建理论框架体系。通过对“非粮化”治理的政策回溯和困境揭示,提出应对逻辑要着眼于底线管控、动态发展和价值实现三个不同维度的治理视角,深入辨析安全与效率、供给与需求、资源与资产的关系。理论框架需参照多层级规划目标、精细化分区管理、全生命周期流程和差别化规则体系的原则,围绕管制基础、管制模式、管制环节和管制手段四个核心内容构建用途管制体系。研究结果可为防止耕地“非粮化”、完善耕地保护制度提供参考。

关键词：耕地保护国土空间用途管制耕地“进出平衡” 大食物观 “两山”转化全生命周期

In-flight Energy Calibration of the gECAM gamma-ray Detectors

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Research in Astronomy and Astrophysics 2024年第10期24卷 48-57页

作者： Rui Qiao Dong-ya.guo Wen-Xi Peng ya.-Qiu Zhang Shuo Xiao Shao-Lin Xiong Chao Zheng Chao-ya.g Li Jia-Cong Liu Wang-Chen Xue Jian-Jian He Zheng-hua An Da-Li Zhang Xin-Qiao Li Li-Ming Song Shi-Jie Zheng Ke gong ya.Qing Liu Xin-Ying Song Xiao-Yun Zhao Xiang-ya.g Wen ya.-Bing Xu Xiang Ma Xiao-Bo Li Ping Wang Yue hua.g Ce Cai Qi-Bin Yi Yi Zhao Chen-Wei Wang Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China China West Normal University Nanchong 637002China Xiangtan University Xiangtan 411105China Beijing Normal University Beijing 100875China

The gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor(gECAM)mission is designed to monitor the gamma-Ray Bursts(gRBs)associated with gravitational waves and other high-energy transient *** mission consists of two microsatellites which are planned to operate at the opposite sides of the *** gECAM satellite could detect and localize gRBs in about 8 keV-5 MeV with its 25 gamma-Ray Detectors(gRDs).In this work,we report the in-flight energy calibration of gRDs using the characteristic gamma-ray lines in the background spectra,and show their performance evolution during the commissioning ***,a preliminary cross-calibration of energy response with Fermi gBM data is also presented,validating the energy response of gRDs.

关键词： (stars:)gamma-ray burst:general instrumentation:detectors methods:data analysis

基因编辑技术在猪分子育种中的研究进展及发展趋势

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农业生物技术学报 2024年第8期32卷 1939-1948页

作者：赵娅娅袁利明华进联西北农林科技大学动物医学院陕西省干细胞工程技术研究中心

基因编辑技术为猪(Sus scrofa)分子育种提供了新的解决方案。通过基因编辑技术，可以实现精准、高效的基因编辑，为生猪育种工作提供了强大的工具。基因编辑不仅可用于快速、精准地改善生长速度、提高抗病能力，从而增强生猪的饲养效益... 详细信息

基因编辑技术为猪(Sus scrofa)分子育种提供了新的解决方案。通过基因编辑技术，可以实现精准、高效的基因编辑，为生猪育种工作提供了强大的工具。基因编辑不仅可用于快速、精准地改善生长速度、提高抗病能力，从而增强生猪的饲养效益，还能优化猪肉的质量、提升口感，甚至改善其营养成分，以满足消费者对于高品质、健康猪肉的日益增长的需求。然而，基因编辑技术的应用在技术方面仍然存在不小的挑战，例如脱靶效应。因此须加大技术创新，以解决这些制约猪基因编辑育种效率的问题，推动基因编辑技术在猪抗病育种中的广泛应用。本文综述了基因编辑技术在猪分子育种中的最新进展，包括技术进步、应用现状及面临的挑战，为我国生猪抗病育种研究提供参考。

关键词：基因编辑技术猪分子育种挑战

大别山区生境质量时空特征及自然-人为因素驱动机制

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环境科学 2024年第4期45卷 2268-2279页

作者：郑亚平张俊华田惠文朱航成刘舒丁亚鹏河南大学地理与环境学院开封475004 河南大学黄河中下游数字地理技术教育部重点实验室开封475004 河南大别山森林生态系统国家野外科学观测研究站郑州450046

大别山区是中国南北地理生态过渡带东延余脉,山地系统表现出高度的异质性和敏感易变性,识别山地生境质量的空间特征对揭示自然和人为因素的时空驱动机制及差异具有重要指示意义.基于PLUS-InVEST以及地理探测器方法,分析大别山区2000~202... 详细信息

大别山区是中国南北地理生态过渡带东延余脉,山地系统表现出高度的异质性和敏感易变性,识别山地生境质量的空间特征对揭示自然和人为因素的时空驱动机制及差异具有重要指示意义.基于PLUS-InVEST以及地理探测器方法,分析大别山区2000~2020年生境质量的时空动态变化及驱动机制,并对2030年土地利用和生境质量进行多情景模拟预测. 2000~2020年,区内土地利用类型以耕地(50%~54%)和林地(42%~45%)为主,荒地(2%~4%)面积占比最低,大别山区耕地变化最大,面积减少2 311.45 km^(2),林地和建设用地次之,面积分别增加1 431.37 km^(2)和924.52 km^(2),灌木和荒地的变化较小,面积分别减少7.72 km^(2)和19.10 km^(2);大别山区的生境质量与海拔高度呈正相关,中东部生境质量较高,北部和南部生境质量较差;2000~2010年生境质量均值从0.594上升到0.608,到2020年下降到0.603,生境质量出现了先上升后下降的趋势.地理探测器结果表明,影响大别山区生境质量的主要驱动因素是地形起伏度、土地利用强度和海拔,NDVI的影响随着时间逐渐增强. 2030年生境质量的预测结果显示,4种发展情景下,区域内整体生境质量仍然呈现下降的趋势,并且在生态保护情景下,依旧呈现降低的趋势,只是降低的速率减小.研究结果可为大别山区未来土地利用类型空间规划提供优化策略.

关键词： PLUS-InVEST模型生境质量土地利用地理探测器时空变化大别山区

The only purple-flower species in Actaea *** pollinated by a hornet

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Journal of Plant Ecology 2024年第4期17卷 181-196页

作者： Lin-Feng Qiu Jiu-Dong Zhang Ying Li Xiao-Ying Liu Dan-Qing Zhang Long hua.g ya.Peng ya.g Shi-Yu Wang Yue-Yi Li Zi-Wei Ma Jie Sui Lin Wang Xiao-Fen Che Xian-hua Tian Yi Ren Jian-Qiang Zhang National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest China College of Life SciencesShaanxi Normal UniversityXi’an 710119China Key Laboratory of Medicinal Plant Resource and Natural Pharmaceutical Chemistry of Ministry of Education Shaanxi Normal UniversityXi’an 710119China College of Biological and Environmental Engineering Xi’an UniversityXi’an 710065China

Examining the pollination biology of plant species is not only crucial for enhancing our understanding of their reproductive biology,but also essential for elucidating their adaptation and evolutionary ***,we investigated the breeding system and pollination biology of two closely related species in *** flower of *** is unique in the genus with purple and chartaceous(paper-like)sepals,fewer stamens with yellow anthers and purple *** three seasons of field observation and exclusion experiments,we determined that *** was primarily pollinated by a hornet species,Vespa bicolor,which also served as the most efficient *** contrast,*** was primarily pollinated by large *** purpurea exhibited a significantly higher cumulative nectar volume than ***,which could be a crucial factor in attracting ***.A control experiment further demonstrated that removing the nectar leaf(petal)significantly decreased the visiting frequency of *** system studies revealed that both species were self-compatible,yet they primarily underwent outcrossing in natural *** study presents a compelling case of possible pollinator shift in *** accompanied by morphological divergence.A more in-depth investigation of this system would offer crucial insights into the extent to which pollinators are involved in the plant speciation process and whether they contribute to reproductive isolation between closely related species.

关键词： Actaea purpurea Actaea japonica breeding system pollinator shift speciation Vespa bicolor

gigahertz-rate-switchable wavefront shaping through integration of metasurfaces with photonic integrated circuit

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Advanced Photonics 2024年第1期6卷 106-114页

作者： Haozong Zhong Yong Zheng Jiacheng Sun Zhizhang Wang Rongbo Wu Ling-en Zhang Youting Liang Qinyi hua Minghao Ning Jitao Ji Bin Fang Lin Li Tao Li ya.Cheng Shining Zhu East China Normal University School of Physics and Electronic ScienceState Key Laboratory of Precision SpectroscopyShanghaiChina Nanjing University College of Engineering and Applied SciencesNational Laboratory of Solid State MicrostructuresNanjingChina China Jiliang University College of Optical and Electronic TechnologyHangzhouChina Shanxi University Collaborative Innovation Center of Extreme OpticsTaiyuanChina Chinese Academy of Sciences(CAS) Shanghai Institute of Optics and Fine Mechanics(SIOM)State Key Laboratory of High Field Laser Physics and CAS Center for Excellence in Ultra-Intense Laser ScienceShanghaiChina

Achieving spatiotemporal control of light at high speeds presents immense possibilities for various applications in communication,computation,metrology,and *** integration of subwavelength metasurfaces and optical waveguides offers a promising approach to manipulate light across multiple degrees of freedom at high speed in compact photonic integrated circuit(PIC)***,we demonstrate a gigahertz-rate-switchable wavefront shaping by integrating metasurface,lithium niobate on insulator photonic waveguides,and electrodes within a PIC *** proofs of concept,we showcase the generation of a focus beam with reconfigurable arbitrary polarizations,switchable focusing with lateral focal positions and focal length,orbital angular momentum light beams as well as Bessel *** measurements indicate modulation speeds of up to the gigahertz *** integrated platform offers a versatile and efficient means of controlling the light field at high speed within a compact system,paving the way for potential applications in optical communication,computation,sensing,and imaging.

关键词： metasurface photonic integrated circuit lithium niobate on insulator high-speed modulation

兰州市南北两山土壤水分遥感反演及植被需水量估算

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干旱区研究 2024年第4期41卷 566-580页

作者：张华押海廷徐存刚西北师范大学地理与环境科学学院甘肃兰州730070

探究西北干旱区土壤水分和植被需水量动态变化特征,可为生态恢复不同阶段所需水资源量及水资源优化配置提供科学依据。以兰州市南北两山为研究区,基于Sentinel-2 L2A和Landsat 8 OLI遥感影像,结合实测土壤0~10 cm的111个数据,分别构建... 详细信息

探究西北干旱区土壤水分和植被需水量动态变化特征,可为生态恢复不同阶段所需水资源量及水资源优化配置提供科学依据。以兰州市南北两山为研究区,基于Sentinel-2 L2A和Landsat 8 OLI遥感影像,结合实测土壤0~10 cm的111个数据,分别构建垂直干旱指数(Perpendicular Drought Index,PDI)、改进型垂直干旱指数(Modified Perpendicular Drought Index,MPDI)和植被调整垂直干旱指数(Vegetation-adjusted Perpendicular Drought Index,VAPDI)土壤水分反演模型,并采用4种模型指标定量决定系数(R^(2))、平均绝对误差(MAE)、平均相对误差(MRE)、均方根误差(RMSE)对模型反演的效果进行精度评价,选出最优的土壤水分反演模型并结合土壤水分限制系数,与研究区2019年林地、草地和耕地植被面积的空间数据、各站点生长季内的参考作物蒸散量,构建植被生态需水量模型,厘清研究区内土壤水分、植被需水量时空变化特征。结果表明:(1)2种数据源下的PDI、MPDI、VAPDI和实测数据之间均有着不同程度的线性负相关性,其中R^(2)分别为0.37、0.64和0.59,从评价指标的结果来看,MPDI的土壤水分回归模型的拟合决定系数最高,2种遥感数据反演的土壤水分空间分布格局具有一致性。(2)分辨率高的Sentinel-2L2A土壤水分反演更加精细,土壤水分整体呈波动增长趋势,多时段土壤水分的平均值为23.27%,呈现出降低再增加然后下降,总体增幅为74.07%。(3)兰州市南北两山4—10月植被需水量月均值也呈现先增加后下降的趋势,与土壤水分含量变化具有一致性,4—10月中7月植被需水量最大,为3.98×10^(7)m^(3),10月植被生态需水量最小,为0.97×10^(7)m^(3)。随着环境绿化工程的实施,兰州市南北两山从只能生长耐旱草本和低矮灌木的植物,逐步形成以多种类结合的群落结构。本研究可为兰州市南北两山土壤水资源合理利用及植被恢复提供参考。

关键词：土壤水分遥感反演植被需水量兰州市南北两山

机械门控离子通道Piezo1调节巨噬细胞参与炎症反应研究进展

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中国疼痛医学杂志 2024年第2期30卷 119-124页

作者：谢亚飞杭黎华江苏大学附属昆山医院麻醉科苏州215300

压电型机械门控离子通道组件1(piezo-type mechanosensitive ion channel component 1,Piezo1)是哺乳动物体内转导机械刺激信号的主要通道,在调节尿渗透压、控制血压和运动性能、调节上皮细胞增殖与分裂等方面发挥重要作用。机械损伤是... 详细信息

压电型机械门控离子通道组件1(piezo-type mechanosensitive ion channel component 1,Piezo1)是哺乳动物体内转导机械刺激信号的主要通道,在调节尿渗透压、控制血压和运动性能、调节上皮细胞增殖与分裂等方面发挥重要作用。机械损伤是炎症诱发因素之一,但机械力诱发炎症的具体机制尚不完全清楚。近年来的研究表明,Piezo1通过介导有关信号通路以及有氧糖酵解等途径调控巨噬细胞参与多种炎症性疾病的过程。本文就Piezo1在该方面的最新研究进展进行综述。

关键词： Piezo1 巨噬细胞炎症反应信号通路