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东亚季风区石笋δ^(18)O解译:基于夏季风与夏季风降雨的思考

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地质科技通报 2022年第5期41卷 308-314,323页

作者：殷建军中国地质科学院岩溶地质研究所自然资源部/广西岩溶动力学重点实验室广西桂林541004

近些年,对于东亚季风区石笋δ^(18)O的气候环境指示意义的争论较多,主要在东亚季风区石笋δ^(18)O代表夏季和风强度、夏季风降水还是水汽源变化。基于中国东部华北地区降水与长江中下游地区降水反相变化和长江中下游地区降水与菲律宾海... 详细信息

近些年,对于东亚季风区石笋δ^(18)O的气候环境指示意义的争论较多,主要在东亚季风区石笋δ^(18)O代表夏季和风强度、夏季风降水还是水汽源变化。基于中国东部华北地区降水与长江中下游地区降水反相变化和长江中下游地区降水与菲律宾海降水反相变化(遥相关),从年际-年代际到千年-轨道尺度对石笋δ^(18)O与夏季风降水、厄尔尼诺-南方涛动(ENSO)的相互关系进行了探讨分析。通过对比石笋δ^(18)O记录与华北和梅雨区降水,发现石笋δ^(18)O偏负对应华北降水增加,梅雨区降水减少;石笋δ^(18)O偏正对应华北降水减少,梅雨区降水增加。这种对应关系不仅存在年际-年代际尺度,而且在千年-轨道尺度同样存在,石笋δ^(18)O不仅反映夏季风强弱变化,同时与中国东部区域降水关系是明确对应的。通过降水的空间相互关系,发现ENSO活动主要通过影响中国东部降水的空间分布格局而作用于石笋δ^(18)O。La Ni a态导致南海及菲律宾海对流加强,西太副高位置偏北,长江中下游地区梅雨期缩短,华北夏季降水增加,东亚季风区石笋δ^(18)O偏负。El Ni o态,南海和菲律宾海对流受到抑制,西太副高位置南移,长江中下游地区梅雨期延长,华北夏季降水减少,东亚季风区石笋δ^(18)O偏正。另外,水汽源分析发现,菲律宾海水汽输送对东亚季风区降水及降水δ^(18)O贡献相对较小。因此,综合分析认为,东亚季风区石笋δ^(18)O主要反映了亚洲夏季风的强弱变化。

关键词：石笋δ^(18)O 东亚季风区夏季风厄尔尼诺-南方涛动指数(ENSO) 梅雨区菲律宾海

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Synergistic effects of carbon cycle metabolism and photosynthesis in Chinese cabbage under salt stress

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Horticultural Plant Journal 2024年第2期10卷 461-472页

作者： Hao Liang Qiling Shi Xing Li Peipei Gao Daling Feng Xiaomeng Zhang yin Lu Jingsen Yan Shuxing Shen jianjun Zhao Wei Ma State Key Laboratory of North China Crop Improvement and Regulation Key Laboratory of Vegetable Germplasm Innovation and Utilization of HebeiCollaborative Innovation Center of Vegetable Industry in HebeiCollege of HorticultureHebei Agricultural UniversityBaodingHebei 071000China

Chinese cabbage(Brassica rapa ssp. pekinensis) has a long cultivation history and is one of the vegetable crops with the largest cultivation area in China. However, salt stress severely damages photosynthesis and hormone metabolism, nutritional balances, and results in ion toxicity in plants. To better understand the mechanisms of salt-induced growth inhibition in Chinese cabbage, RNA-seq and physiological index determination were conducted to explore the impacts of salt stress on carbon cycle metabolism and photosynthesis in Chinese cabbage. Here, we found that the number of thylakoids and grana lamellae and the content of starch granules and chlorophyll in the leaves of Chinese cabbage under salt stress showed a time-dependent response, first increasing and then decreasing. Chinese cabbage increased the transcript levels of genes related to the photosynthetic apparatus and carbon metabolism under salt stress, probably in an attempt to alleviate damage to the photosynthetic system and enhance CO_(2) fixation and energy metabolism. The transcription of genes related to starch and sucrose synthesis and degradation were also enhanced;this might have been an attempt to maintain intracellular osmotic pressure by increasing soluble sugar concentrations. Soluble sugars could also be used as potential reactive oxygen species(ROS) scavengers, in concert with peroxidase(POD)enzymes, to eliminate ROS that accumulate during metabolic processes. Our study characterizes the synergistic response network of carbon metabolism and photosynthesis under salt stress.

关键词： Chinese cabbage Salt stress Carbon metabolism Photosynthesis Chloroplast

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基于断层切片透视的双目测量模型

江苏大学学报（自然科学版） 2011年第3期32卷 249-253页

作者：尹建军毛罕平江苏大学现代农业装备与技术省部共建教育部重点实验室/江苏省重点实验室江苏镇江212013

从双目定位的几何分析出发，提出了一种基于断层切片透视的双目测量模型．该模型首先建立了不同深度距离下物点视差与深度距离的非线性关系，然后在物点深度距离已知的情况下，使用预先建立的各个断层切片距离下的神经网络映射模型，根... 详细信息

从双目定位的几何分析出发，提出了一种基于断层切片透视的双目测量模型．该模型首先建立了不同深度距离下物点视差与深度距离的非线性关系，然后在物点深度距离已知的情况下，使用预先建立的各个断层切片距离下的神经网络映射模型，根据物点的图像坐标确定其2维X，Y坐标．当切片距离与建模时深度距离不一致时，采用最近邻原则到最接近距离下的模型进行近似．结果表明：该测量模型从深度距离223mm到1183mm的97个断层切片位置，在Z方向的最大绝对误差不超过4．5mm，在X，Y方向的最大绝对误差均不超过2．0mm，偏离真实点空间距离的误差在0．2416～4．8590mm之间变化．试验表明：该模型可以满足果实空间定位的测量精度要求．

关键词：双目测量神经网络定位番茄模型

Associations Between Air Temperature and Daily Varicella Cases—Jinan City,Shandong Province,China,2019–2021

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China CDC weekly 2024年第2期6卷 36-39,I0008,I0009页

作者： Guijie Luan Yuehua Hu Meng Chen Meiying You Chengdong Xu Dapeng yin jianjun Liu Hongyan Yao Chinese Center for Disease Control and Prevention BeijingChina Institute for Immunization management Shandong Center forDisease Control and PreventionJinan CityShandong ProvinceChina State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina Hainan Provincial Center for Disease Control and Prevention Haikou CityHainan ProvinceChina.

What is already known about this topic?The impact of air temperature on varicella has been studied,but there is limited research exploring its effect on varicella by gender and age *** is added by this report?We conducted a time series analysis to examine the differential effects of air temperature on varicella infection across different demographic *** findings indicate that lower temperatures have a more pronounced influence on varicella incidence among males and children compared to females and *** are the implications for public health practice?These findings can assist in identifying populations that are vulnerable to temperature-related varicella and in guiding the implementation of effective measures for varicella control.

关键词： finding measures Shandong

Grassland-type ecosystem stability in China differs under the influence of drought and wet events

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Journal of Arid Land 2024年第5期16卷 615-631页

作者： CAO Wenyu BAI jianjun YU Leshan School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China International Business School Shaanxi Normal UniversityXi'an 710119China

Ecological stability is a core issue in ecological research and holds significant implications forhumanity. The increased frequency and intensity of drought and wet climate events resulting from climatechange pose a major threat to global ecological stability. Variations in stability among different ecosystemshave been confirmed, but it remains unclear whether there are differences in stability within the sameterrestrial vegetation ecosystem under the influence of climate events in different directions and ***'s grassland ecosystem includes most grassland types and is a good choice for studying this *** study used the Standardized Precipitation Evapotranspiration Index-12 (SPEI-12) to identify thedirections and intensities of different types of climate events, and based on Normalized DifferenceVegetation Index (NDVI), calculated the resistance and resilience of different grassland types for 30consecutive years from 1990 to 2019 (resistance and resilience are important indicators to measurestability). Based on a traditional regression model, standardized methods were integrated to analyze theimpacts of the intensity and duration of drought and wet events on vegetation stability. The resultsshowed that meadow steppe exhibited the highest stability, while alpine steppe and desert steppe had thelowest overall stability. The stability of typical steppe, alpine meadow, temperate meadow was at anintermediate level. Regarding the impact of the duration and intensity of climate events on vegetationecosystem stability for the same grassland type, the resilience of desert steppe during drought was mainlyaffected by the duration. In contrast, the impact of intensity was not significant. However, alpine steppewas mainly affected by intensity in wet environments, and duration had no significant impact. Ourconclusions can provide decision support for the future grassland ecosystem governance.

关键词： grassland ecosystem stability resistance resilience different climate types drought climate event wet climate event

Coseismic Coulomb stress changes induced by a 2020-2021 M_(W)>7.0 Alaska earthquake sequence in and around the Shumagin gap and its influence on the Alaska-Aleutian subduction interface

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Geodesy and Geodynamics 2024年第1期15卷 1-12页

作者： Lei Yang jianjun Wang Caijun Xu School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China Collaborative Innovation Center of Geospatial Technology Wuhan 430079China Key Laboratory of Geospace Environment and Geodesy Ministry of EducationWuhan UniversityWuhan 430079China

Three M_(W)>7.0 earthquakes in 2020-2021 occurred in the Shumagin seismic gap and its adjacent area of the Alaska-Aleutian subduction zone,including the Mw7.8 Simeonof thrust earthquake on July 22,2020,the M_(W)7.6 Sand Point strike-slip earthquake on October 19,2020,and the M_(W)8.2 Chignik thrust earthquake on July 29,*** spatial and temporal proximity of these three earthquakes prompts us to probe stress-triggering effects among *** we examine the coseismic Coulomb stress change imparted by the three earthquakes and their influence on the subduction *** results show that:(1)The Simeonof earthquake has strong loading effects on the subsequent Sand Point and Chignik earthquakes,with the Coulomb stress changes of 3.95 bars and 2.89 bars,*** Coulomb stress change caused by the Sand Point earthquake at the hypocenter of the Chignik earthquake is merely around 0.01 bars,suggesting the negligible triggering effect on the latter earthquake;(2)The triggering effects of the Simeonof,Sand Point,and Chignik earthquakes on aftershocks within three months are not well pronounced because of the triggering rates of 38%,14%,and 43%*** factors may have played an important role in promoting the occurrence of these aftershocks,such as the roughness of the subduction interface,the complicated velocity structure of the lithosphere,and the heterogeneous prestress therein;(3)The three earthquakes caused remarkable coseismic Coulomb stress changes at the subduction interface nearby these mainshocks,with an average Coulomb stress change of 3.2 bars in the shallow region directly inwards the trench.

关键词： The 2020-2021 Alaska earthquake sequence Coseismic Coulomb stress change Mainshock-aftershock triggering The Alaska-Aleutian subduction interface The Shumagin gap

Single transmembrane GPCR modulating proteins:neither single nor simple

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Protein & Cell 2024年第6期15卷 395-402页

作者： Meng Wang jianjun Lyu Chao Zhang Department of Plastic and Reconstructive Surgery Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai 200011China Hubei Topgene Research Institute of Hubei Topgene Biotechnology Co. LtdEast Lake High-Tech Development ZoneWuhan 430205China Fundamental Research Center Shanghai Yangzhi Rehabilitation Hospital (Shanghai Sunshine Rehabilitation Center)Tongji UniversityShanghai 200092China

The discovery of G-protein coupled receptor(GPCR)accessory proteins has fundamentally redefined the pharmacological concept of GPCR signaling,demonstrating a more complex molecular basis for receptor specificity on the plasma membrane and impressionable downstream intracellular *** accessory proteins not only contribute to the proper folding and trafficking of receptors but also exhibit selectable receptor preferences.

关键词： specificity GPCR neither

Effect of hot isostatic pressure on the microstructure and tensile properties of γ'-strengthened superalloy fabricated through induction-assisted directed energy deposition

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1089-1097页

作者： jianjun Xu Hanlin Ding Xin Lin Feng Liu Analytical&Testing Center Northwestern Polytechnical UniversityXi’an 710072China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China

The microstructure characteristics and strengthening mechanism of Inconel738LC(IN-738LC) alloy prepared by using induction-assisted directed energy deposition(IDED) were elucidated through the investigation of samples subjected to IDED under 1050℃ preheating with and without hot isostatic pressing(HIP,1190℃,105 MPa,and 3 h).Results show that the as-deposited sample mainly consisted of epitaxial columnar crystals and inhomogeneously distributed γ’ phases in interdendritic and dendritic core *** HIP,grain morphology changed negligibly,whereas the size of the γ’ phase became increasingly *** further heat treatment(HT,1070℃,2 h + 845℃,24 h),the γ’ phase in the as-deposited and HIPed samples presented a bimodal size distribution,whereas that in the as-deposited sample showed a size that remained *** comparison of tensile properties revealed that the tensile strength and uniform elongation of the HIP + HTed sample increased by 5% and 46%,respectively,due to the synergistic deformation of bimodal γ’phases,especially large cubic γ’ ***,the relationship between phase transformations and plastic deformations in the IDEDed sample was discussed on the basis of generalized stability theory in terms of the trade-off between thermodynamics and kinetics.

关键词： directed energy deposition Ni-based superalloys high-temperature preheating hot isostatic pressing microstructure tensile properties

Design and synthesis of thiol-terminated imidothioether oligomer as thermally latent hardener and modifier for high-performance epoxy/thiol thermosets

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Science China Chemistry 2024年第2期67卷 632-641页

作者： Xing Liu jianjun Zhou Shumei Liu Jianqing Zhao School of Materials Science and Engineering South China University of TechnologyGuangzhou510640China Key Lab Guangdong High Property&Functional Polymer Materials Key Laboratory of Polymer Processing EngineeringMinistry of EducationGuangzhou510640China

Conventional base-catalyzed epoxy/aliphatic thiol systems have a poor storage stability,and are impossible to be one-pot systems.A widely accepted solution is to use the latent catalysts,which are usually insoluble anionic initiators sensitive to impurities and moisture,and have many limitations in practical *** this work,a soluble thiol-terminated imidothioether oligomer(TPI) was synthesized and used as a latent hardener and modifier to prepare one-pot epoxy/thiol systems without the latent *** latent behavior and curing mechanism of epoxy systems(EP/TPI series),consisted of bisphenol A diglycidyl ether(DGEBA),pentaerythritol tetrakis(mercaptoacetate)(PETMP) and TPI,were *** thiol exchange reaction between TPI and PETMP preceded the curing reaction of DGEBA,and produced aromatic thiols,which were unreactive at ambient conditions and reacted with DGEBA to form the thermosets at temperatures above 130 ℃.At the loading of 24.4 wt%TPI,the epoxy system(EP/TPI-3) had a shelf life of 13 days and was completely cured within 20 min at 180 ℃.Meanwhile,the catalyst-free curing process of EP/TPI-3 system was insensitive to impurities and ***,the thermal and mechanical properties of EP/TPI-3 thermoset were simultaneously improved,thereinto,the glass transition temperature,Young's modulus and ultimate tensile strength were increased by 16.7 ℃,12.9%,and 13.6%,respectively,compared with those of the commercial DGEBA/PETMP *** work shows that TPI has the potential to be a powerful alternative to commercial latent catalysts,and EP/TPI thermosets with high performance have broad application prospects.

关键词： thiol-terminated imidothioether oligomer epoxy systems thiol exchange reaction thermal latency high performance