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New Insights on Gamma-Ray Burst Radiation Mechanisms from Multiwavelength Observations

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Research in Astronomy and Astrophysics 2025年第2期25卷 3-12页

作者： Yu-Hua yao Fang-Sheng Min Shi Chen Yi-qing Guo College of Physics Chongqing University Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Wisconsin Ice Cube Particle Astrophysics Center University of Wisconsin–Madison University of Chinese Academy of Sciences School of Physics and Astronomy Yunnan University Tianfu Cosmic Ray Research Center

The study of high-energy gamma-ray emission from gamma-ray bursts(GRBs) involves complex synchrotron radiation and synchrotron self-Compton(SSC) scattering mechanisms with multiple parameters exhibiting a wide distribution. Recent advancements in GRB research, particularly the observation of very high energy(VHE,>100 Ge V) radiation, have ushered in a new era of multiwavelength exploration, offering fresh perspectives and limitations for understanding GRB radiation mechanisms. This study aimed to leverage VHE observations to refine constraints on synchrotron + SSC radiation from electrons accelerated by forward shocks. By analyzing two external environments—the uniform interstellar medium and stratified stellar wind medium, we conducted spectral and variability fitting for five specific bursts(GRB 180720B, GRB 190114C, GRB 190829A, GRB 201216C, and GRB 221009A) to identify the optimal parameters characterizing these events. A comparative analysis of model parameter distributions with and without VHE radiation observations reveals that the magnetic energy equipartition factor εBis more concentrated with VHE emissions. This suggests that VHE emissions may offer greater constraints on this microphysical parameter. Additionally, we found that the energy budget between VHE and ke V–Me V γ-ray emissions under the SSC radiation exhibits an almost linear relationship, which may serve as a tool to differentiate radiation mechanisms. We anticipate future statistical analyses of additional VHE bursts to validate our findings.

关键词： (transients:) gamma-ray bursts gamma-rays: ISM radiation mechanisms: non-thermal

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聚乙二醇对望江南种子萌发的影响

中草药 2009年第9期40卷 1466-1469页

作者：何家庆王兴姚晴晴安徽大学生命科学学院安徽省资源植物研究中心安徽合肥230039 中国农业大学资源与环境学院北京100193

目的以PEG6000溶液处理望江南种子,研究PEG对望江南种子萌发的影响。方法分别用5%和10%PGE6000处理望江南种子,对种子发芽率、超氧化物歧化酶(SOD)、过氧化物酶(POD)活性和脂质过氧化产物丙二醛(MDA)的量进行测定。结果与同期对照相比,5... 详细信息

目的以PEG6000溶液处理望江南种子,研究PEG对望江南种子萌发的影响。方法分别用5%和10%PGE6000处理望江南种子,对种子发芽率、超氧化物歧化酶(SOD)、过氧化物酶(POD)活性和脂质过氧化产物丙二醛(MDA)的量进行测定。结果与同期对照相比,5%PEG6000浸种5h,提高SOD活性和POD活性,降低脂质过氧化产物MDA的量,减少自由基积累,减轻浸种吸胀对膜系统的损伤。结论5%PEG浸种5h提高望江南种子的发芽率。

关键词：聚乙二醇望江南种子萌发

Mechanism for ginkgolic acid(15：1)-induced MDCK cell necrosis： Mitochondria and lysosomes damages and cell cycle arrest

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Chinese Journal of Natural Medicines 2017年第5期15卷 375-383页

作者： yao qing-qing LIU Zhen-Hua XU Ming-Cheng HU Hai-Hong ZHOU Hui JIANG Hui-Di YU Lu-Shan ZENG Su Institute of Drug Metabolism and Pharmaceutical Analysis Zhejiang Province Key Laboratory of Anti-Cancer Drug Research College of Pharmaceutical Sciences Zhejiang University Hangzhou 310058 China

Ginkgolic acids(GAs), primarily found in the leaves, nuts, and testa of ginkgo biloba, have been identified with suspected allergenic, genotoxic and cytotoxic properties. However, little information is available about GAs toxicity in kidneys and the underlying mechanism has not been thoroughly elucidated so far. Instead of GAs extract, the renal cytotoxicity of GA(15 : 1), which was isolated from the testa of Ginkgo biloba, was assessed in vitro by using MDCK cells. The action of GA(15 : 1) on cell viability was evaluated by the MTT and neutral red uptake assays. Compared with the control, the cytotoxicity of GA(15 : 1) on MDCK cells displayed a time-and dose-dependent manner, suggesting the cells mitochondria and lysosomes were damaged. It was confirmed that GA(15 : 1) resulted in the loss of cells mitochondrial trans-membrane potential(ΔΨm). In propidium iodide(PI) staining analysis, GA(15 : 1) induced cell cycle arrest at the G0/G1 and G2/M phases, influencing on the DNA synthesis and cell mitosis. Characteristics of necrotic cell death were observed in MDCK cells at the experimental conditions, as a result of DNA agarose gel electrophoresis and morphological observation of MDCK cells. In conclusion, these findings might provide useful information for a better understanding of the GA(15 : 1) induced renal toxicity.

关键词： Ginkgolic acids(15:1) Cytotoxicity Mechanism Necrosis

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基于时变小世界模型的航空网优化评估

物理学报 2017年第24期66卷 267-274页

作者：韩定定姚清清陈趣钱江海华东师范大学信息科学技术学院上海市多维度信息处理重点实验室上海200241 上海电力学院数理学院上海200090

航空网的优化设计对于优化资源配置、改善航运效率、提高航空公司竞争力等具有重要的现实意义.而航线结构与航班计划密不可分.本文首先讨论了航空网的时变特征,揭示了航班频率与航线距离之间的时空耦合关联.通过构建时变空间小世界模型... 详细信息

航空网的优化设计对于优化资源配置、改善航运效率、提高航空公司竞争力等具有重要的现实意义.而航线结构与航班计划密不可分.本文首先讨论了航空网的时变特征,揭示了航班频率与航线距离之间的时空耦合关联.通过构建时变空间小世界模型,揭示了时变条件下网络的最优结构指数与时空耦合强度的惟一约束关系.以运行总成本最小化为主要优化目标,提出了一种可以快速评估航线结构优化情况的方法.该方法能根据网络客流分布情况快速推算出航线网络的最优拓扑及相应的航班频率分布.并用2001—2010年中国航空网络数据对此方案进行实证研究,发现预测与实际数据基本符合,并逐渐趋于稳定.这一方法能把复杂问题简单化,对各个航空公司每年的航线航班调整是否合理,现有的航空网络是否在逐步优化做出动态评估.分析航空网络的发展趋势,从而对未来的优化提供建议.

关键词：航空网时变优化空间

Melon2K array:A versatile 2K liquid SNP chip for melon genetics and breeding

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Horticultural Plant Journal 2025年第1期11卷 314-322页

作者： qing Yu Shuai Li Xiaofeng Su Xinxiu Chen Yuanhua Dong Zhiwang yao Naiyu Jiang Sen Chai Zhonghua Zhang Kuipeng Xu Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province College of HorticultureQingdao Agriculture UniversityQingdaoShandong 266109China Key Laboratory of Special Food Proceing(Coconstructionby Ministry and Province) Ministryof Agriculture Rural AairsQingdao Agriculural UniversityQingdaoShandong 266109China Shandong Technology Innovation Center of Special Food QingdaoShandong 266109China qingdao Special Food Research Institute QingdaoShandong 266109China Genome Analysis Laboratory of the Ministry of Agriculture Agricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhenGuangdong 518124China Institute of Vegetables and Flowers Chinese Academy of Agricultural SciencesKey Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of AgricultureSino-Dutch Joint Laboratory of Horticultural GenomicsBeijing 100081China

High-throughput genotyping tools can effectively promote molecular breeding in *** this study,genotyping by target sequencing(GBTS)system was utilized to develop a genome-wide liquid SNP chip for facilitating genetics and breeding in melon(Cucumis melo L.),a globally cultivated economically important horticultural *** on over eight million SNPs derived from 823 representative melon accessions,16K,8K,4K,2K,1K,500,250 and 125 informative SNPs were screened and evaluated for their polymorphisms,conservation of flanking sequences,and *** set of 2K SNPs was found to be optimal for representing the maximum diversity with the lowest number of SNPs,and it was selected to develop the liquid chip,named“Melon2K”.Using Melon2K,more than 1500 SNPs were detected across 17 samples of five melon cultivars,and the phylogenetic relationships were clearly *** the same cultivar,genetic differences were also assessed between different *** evaluated the performance of Melon2K in genetic background selection during the breeding process,obtaining the introgression lines of interested trait with more than 97%genetic background of elite variety by only two rounds of *** results suggest that Melon2K provides a cost-effective,efficient and reliable platform for genetic analysis and molecular breeding in melon.

关键词： Melon Cucumis melo L. Melon2K Liquid SNP chip Cultivar identification Background selection

层状盐岩石膏夹层在腐蚀条件下断裂韧度试验及其弱化机制研究

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岩土力学 2017年第7期38卷 1933-1942页

作者：孟涛胡耀青付庆楠冯淦靳佩华太原理工大学采煤工艺研究所山西太原030024 太原理工大学力学学院山西太原030024

国内盐岩矿床的典型特征是夹层多,其中云应、平顶山地区多为石膏夹层。盐岩储库在建造和运行过程中,夹层会浸泡在卤水和石油中。为了研究石膏夹层在腐蚀条件下的断裂韧度和弱化损伤机制,采用国际岩石力学学会建议的V形切槽巴西圆盘试验(... 详细信息

国内盐岩矿床的典型特征是夹层多,其中云应、平顶山地区多为石膏夹层。盐岩储库在建造和运行过程中,夹层会浸泡在卤水和石油中。为了研究石膏夹层在腐蚀条件下的断裂韧度和弱化损伤机制,采用国际岩石力学学会建议的V形切槽巴西圆盘试验(CCNBD)试件,分别将其浸泡在淡水、半饱和卤水、饱和卤水和酸性石油中,温度分别为20℃、50℃、80℃,浸泡时间为1个月,并与干试件进行对比。研究结果表明:同一种液体浸泡后,石膏的断裂韧度随着温度的升高而急剧下降,而同一温度下,石膏的断裂韧度随着卤水的浓度增大基本不变。水和卤水浸泡后的石膏断裂韧度变化程度要大于酸性石油。石膏在水和卤水浸泡后的弱化机制是由于水-温度-氯离子的作用,其中水-温度的作用占主导,氯离子的侵蚀作用较小;酸性石油浸泡后的弱化机制是因为温度破坏了氢键及受热膨胀,同时另一原因是石膏和酸性石油(环烷酸)发生弱反应。环烷酸和石膏发生环烷酸钙,而环烷酸钙溶于油相有利于反应正向进行。上述研究对评估盐岩储库的稳定性及其密闭性具有重要意义。

关键词：层状盐岩石膏夹层断裂韧度氯离子

壳聚糖/羟基磷灰石复合骨折内固定棒材的制备与性能研究

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功能材料 2011年第1期42卷 128-131页

作者：孙珍珍蔡汝汝蒲曦鸣杨云姚清清侯振清张其清厦门大学生物医学工程研究中心/材料学院福建省生物医学工程重点实验室厦门市生物医学工程技术研究中心福建厦门361005 中国医学科学院中国协和医科大学生物医学工程研究所天津市生物医学材料重点实验室天津300192

采用原位沉析法制备了壳聚糖/羟基磷灰石(CS/HA)复合棒材。用预先沉积的壳聚糖膜将含有Ca、P源的壳聚糖溶液与凝固液隔离,同时控制壳聚糖沉积与羟基磷灰石前驱体转化为羟基磷灰石的过程,使二者得以均匀复合。燃烧试验结果表明无机成分... 详细信息

采用原位沉析法制备了壳聚糖/羟基磷灰石(CS/HA)复合棒材。用预先沉积的壳聚糖膜将含有Ca、P源的壳聚糖溶液与凝固液隔离,同时控制壳聚糖沉积与羟基磷灰石前驱体转化为羟基磷灰石的过程,使二者得以均匀复合。燃烧试验结果表明无机成分均匀分散于壳聚糖中,FT-IR、XRD和TEM测试证实原位生成羟基磷灰石,弯曲强度测试结果表明,原位沉析法制备的材料具有层状结构,CS/HA(质量比20/4)复合材料弯曲强度达133MPa,弯曲模量6.8GPa。

关键词：壳聚糖羟基磷灰石原位沉析内固定

Infiltration by monocytes of the central nervous system and its role in multiple sclerosis: reflections on therapeutic strategies

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Neural Regeneration Research 2025年第3期20卷 779-793页

作者： Guangyong Zhang qing yao Chubing Long Pengcheng Yi Jiali Song Luojia Wu Wei Wan Xiuqin Rao Yue Lin Gen Wei Jun Ying Fuzhou Hua Department of Anesthesiology the Second Affiliated Hospital of Nanchang UniversityNanchangJiangxi ProvinceChina Key Laboratory of Anesthesiology of Jiangxi Province NanchangJiangxi ProvinceChina

Mononuclear macrophage infiltration in the central nervous system is a prominent feature of neuroinflammation. Recent studies on the pathogenesis and progression of multiple sclerosis have highlighted the multiple roles of mononuclear macrophages in the neuroinflammatory process. Monocytes play a significant role in neuroinflammation, and managing neuroinflammation by manipulating peripheral monocytes stands out as an effective strategy for the treatment of multiple sclerosis, leading to improved patient outcomes. This review outlines the steps involved in the entry of myeloid monocytes into the central nervous system that are targets for effective intervention: the activation of bone marrow hematopoiesis, migration of monocytes in the blood, and penetration of the blood–brain barrier by monocytes. Finally, we summarize the different monocyte subpopulations and their effects on the central nervous system based on phenotypic differences. As activated microglia resemble monocyte-derived macrophages, it is important to accurately identify the role of monocyte-derived macrophages in disease. Depending on the roles played by monocyte-derived macrophages at different stages of the disease, several of these processes can be interrupted to limit neuroinflammation and improve patient prognosis. Here, we discuss possible strategies to target monocytes in neurological diseases, focusing on three key aspects of monocyte infiltration into the central nervous system, to provide new ideas for the treatment of neurodegenerative diseases.

关键词： blood–brain barrier macrophages monocytes multiple sclerosis neuroinflammation review therapy

Intelligent field monitoring system for cruciferous vegetable pests using yellow sticky board images and an improved Cascade R-CNN

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Journal of Integrative Agriculture 2025年第1期24卷 220-234页

作者： Yufan Gao Fei Yin Chen Hong Xiangfu Chen Hang Deng Yongjian Liu Zhenyu Li qing yao School of Computer Science and Technology Zhejiang Sci-Tech UniversityHangzhou 310018China Collaborative Innovation Center Guangdong Academy of Agricultural SciencesGuangzhou 510640China

Cruciferous vegetables are important edible vegetable ***,they are susceptible to various pests during their growth process,which requires real-time and accurate monitoring of these pests for pest forecasting and scientific *** yellow sticky boards is a common way to monitor and trap those pests which are attracted to the yellow *** achieve real-time,low-cost,intelligent monitoring of these vegetable pests on the boards,we established an intelligent monitoring system consisting of a smart camera,a web platform and a pest detection algorithm deployed on a *** the operator sets the monitoring preset points and shooting time of the camera on the system platform,the camera in the field can automatically collect images of multiple yellow sticky boards at fixed places and times every *** pests trapped on the yellow sticky boards in vegetable fields,Plutella xylostella,Phyllotreta striolata and flies,are very small and susceptible to deterioration and breakage,which increases the difficulty of model *** solve the problem of poor recognition due to the small size and breaking of the pest bodies,we propose an intelligent pest detection algorithm based on an improved Cascade R-CNN model for three important cruciferous crop *** algorithm uses an overlapping sliding window method,an improved Res2Net network as the backbone network,and a recursive feature pyramid network as the neck *** results of field tests show that the algorithm achieves good detection results for the three target pests on the yellow sticky board images,with precision levels of 96.5,92.2 and 75.0%,and recall levels of 96.6,93.1 and 74.7%,respectively,and an F_(1) value of *** with other algorithms,our algorithm has a significant advantage in its ability to detect small target *** accurately obtain the data for the newly added pests each day,a two-stage pest matching algorithm was *** algorithm performed well and achieved

关键词： vegetable pests yellow sticky boards intelligent monitoring system deep learning pest detection