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由超拍电子伏特加速器产生的超高能伽马射线气泡

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Science Bulletin 2024年第4期69卷 449-457页

作者： LhaASO Collaboration Zhen Cao Chuandong gao Cong Li Ruo-Yu Liu Ruizhi Yang 不详 Key Laboratory of Particle Astrophyics&Experimental Physics Division&Computing Center Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China TIANFU Cosmic Ray Research Center ChengduChina Institute of Frontier and Interdisciplinary Science Shandong UniversityQingdao 266237China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China University of Science and Technology of China Hefei 230026China

We report the detection of aγ-ray bubble spanning at least 100deg2 in ultra-high energy(UHE)up to a few PeV in the direction of the star-forming region Cygnus X,implying the presence super PeVatron(s)accelerating protons to at least 10 PeV.A log-parabola form with the photon indexΓ(E)=(2.71±0.02)+(0.11±0.02)×log10(E/10 TeV)is found fitting the gamma-ray energy spectrum of the bubble *** sources,“hot spots”correlated with very massive molecular clouds,and a quasi-spherical amorphousγ-ray emitter with a sharp central brightening are observed in the *** the core of~0.5°,spatially associating with a region containing massive OB association(Cygnus OB2)and a microquasar(Cygnus X-3),as well as previously reported multi-TeV sources,an enhanced concentration of UHEγ-rays is observed with 2 photons at energies above 1 *** general feature of the bubble,the morphology,and the energy spectrum,are reasonably reproduced by the assumption of a particle accelerator in the core,continuously injecting protons into the ambient medium.

关键词： Cosmic rays γ-rays Interstellar medium Star cluster

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蛋清溶菌酶的重组合成及粗酶生化特性研究

食品与发酵工业 2023年第4期49卷 209-215页

作者：吴瑕刘志军查健龚国利陕西科技大学食品科学与工程学院陕西西安710021

蛋清溶菌酶是一种天然广谱抗菌物质,在低成本无抗养殖领域具有重要应用价值。目前,蛋清溶菌酶的工业生产主要依赖化学提取,其收率较低。利用微生物重组生产蛋清溶菌酶成为一种具有应用潜力的方法。该研究以毕赤酵母gS115为底盘细胞,构... 详细信息

蛋清溶菌酶是一种天然广谱抗菌物质,在低成本无抗养殖领域具有重要应用价值。目前,蛋清溶菌酶的工业生产主要依赖化学提取,其收率较低。利用微生物重组生产蛋清溶菌酶成为一种具有应用潜力的方法。该研究以毕赤酵母gS115为底盘细胞,构建了蛋清溶菌酶重组分泌表达系统,其发酵上清液的酶活力可达665 U/mL。对粗酶液的生化特性分析表明,在pH依赖性、盐浓度依赖性、热稳定性、金属离子依赖性等方面,该重组蛋清溶菌酶与商品蛋清溶菌酶的性质相近。该研究结果为蛋清溶菌酶的微生物生产提供了参考。

关键词：蛋清溶菌酶毕赤酵母重组蛋白分泌表达生化特性

Dimension of marriage and adultery in The scarlet letter

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Sino-US English Teaching 2007年第9期4卷 62-64页

作者： zha O zhao-xia Department of Foreign Language Teaching and Research Hebei University of Economics and Business Shijiazhuang 050061 China

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黄河流域农业绿色发展水平综合评价分析

中国农业资源与区划 2022年第1期43卷 18-28页

作者：查建平周霞周玉玺山东农业大学经济管理学院泰安271018

[目的]实现农业绿色发展,对于黄河流域高质量发展具有重要的现实意义。通过测度黄河流域农业绿色发展水平,解析其绿色发展水平的时序特征和区域差异,提出黄河流域农业绿色发展的政策建议。[方法]文章运用熵权综合评价法,选取2012—2018... 详细信息

[目的]实现农业绿色发展,对于黄河流域高质量发展具有重要的现实意义。通过测度黄河流域农业绿色发展水平,解析其绿色发展水平的时序特征和区域差异,提出黄河流域农业绿色发展的政策建议。[方法]文章运用熵权综合评价法,选取2012—2018年黄河流域面板数据,从资源节约、环境友好和高效发展三个层面构建农业绿色发展评价指标体系,评价分析黄河流域农业绿色发展水平。[结果]从时序变化来看,2012年以来黄河流域农业绿色发展水平得到显著提高,农业绿色发展综合评价值从2012年的0.153提高到2018年的0.829;2018年资源节约、环境友好、高效发展的评价值分别为0.179、0.502、0.148,资源节约和高效发展是黄河流域农业绿色发展的短板;从区域差异上看,黄河流域各省区农业绿色发展水平区域差异较大,总体上呈现“上下游高中游低”的特点,2018年农业绿色发展水平最高的山东,评价值为0.528,排名最低的宁夏仅为0.317;黄河流域农业绿色发展总体水平较低,农业面源污染问题较为突出。[结论]黄河流域各省区应弥补不足,缩小省域间差异;因地制宜,针对黄河流域的不同地区制定和实施差异化政策;聚焦资源节约和高效发展。

关键词：黄河流域农业绿色发展熵权法指标体系评价

Opinion dynamics in finance and business: a literature review and research opportunities

同方期刊数据库博看期刊评论

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Financial Innovation 2020年第1期6卷 971-992页

作者： Quanbo zha.gang Kou Hengjie zha.g haiming Liang xia Chen Cong‑Cong Li Yucheng Dong School of Management Science and Real Estate Chongqing UniversityChongqing 400045China School of Business Administration Southwestern University of Finance and EconomicsChengdu 611130China Business School Hohai UniversityNanjing 211100China Center for Network Big Data and Decision-Making Business SchoolSichuan UniversityChengdu 610065China School of Economics and Management Southwest Jiaotong UniversityChengdu 610031China

Opinion dynamics is an opinion evolution process of a group of agents,where the final opinion distribution tends to three stable states:consensus,polarization,and *** present,the opinion dynamics models have been extensively studied in differrent *** paper provides a review of opinion dynamics in finance and business,such as,finance,marketing,e-commerce,politics,and group decision ***,identified research challenges have been proposed to promote the future research of this topic.

关键词： Opinion dynamics Financial market Business

Study on the characteristics of grout permeation based on cylindrical diffusion

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Journal of Coal Science & Engineering(China) 2013年第1期19卷 57-62页

作者： Shen-gang LI Wen zha01 Yun-sheng HUANg Yun-xia LEI Long-mei Yu College of Resources and Engineering Northeastern University Shenyang 110819 China China Overseas Property Co. Ltd. Shenyang 110014 China Shenyang Urban-Rural Construction Committee Shenyang 110002 China Dalian Port Construction Supervision & Consultation CO. Ltd Dalian 116015 China

Permeation grouting is widely applied for its low grouting pressure and minor disturbance to the stratum in grouting engineering, especially in engineering with strict requirements on ground settlement. However, permeation grouting theory lags behind compared with other engineering disciplines, and the theoretical formulas now available cannot accurately be used to guide grouting engineering design and predict the cost and effects of grouting due to many factors affecting grout permeation in stratum. In this study, permeation grouting experiment devices were independently manufactured with the characteristics of easily controlling grouting pressure, simulating sandy strata grout, and detecting grouting effect. Using a uniform design, the sand consolidation agent, as grouting material, its spread in Shenyang sandy strata was tested with these experiment devices. The quantitative relations between grouting factors (grouting pressure, strata parameters, water-sand consolidation agent ratio) and grouting effects (grout spread radius, gell strength, grout amount) are obtained with regression analysis, and the influence degree of grouting factors on grouting effects is studied.

关键词：浆液扩散半径灌浆工程渗透注浆地层参数圆柱注浆压力注浆效果实验设备

Hypoxia-induced factor-1 alpha upregulates vascular endothelial growth factor C to promote lymphangiogenesis and angiogenesis in breast cancer patients

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The Journal of Biomedical Research 2013年第6期27卷 478-485页

作者： xiaojian Ni Yingchun zhao Jingjing Ma Tiansong xia xiaoan Liu Qiang Ding xiaoming zha Shui Wang Department of Breast Surgery The First Affiliated Hospital of Nanjing Medical University Department of Breast Surgery The Second People's Hospital Affiliated with Wannan Medical College State Key Laboratory of Reproductive Medicine Department of Breast Surgery Nanjing Maternity and Child Health Care Hospital Affiliated to Nanjing Medical University

Hypoxia-induced factor-1 alpha （HIF-1α） affects many effector molecules and regulates tumor lymphangio- genesis and angiogenesis during hypoxia. The aim of this study was to investigate the role of HIF-1α in the regu- lation of vascular endothelial growth factor C （VEgF-C） expression and its effect on lymphangiogenesis and an- giogenesis in breast cancer. Lymphatic vessel density （LVD）, microvessel density （MVD） and the expressions of HIF-1α and VEgF-C proteins were evaluated by immunohistochemistry in 75 breast cancer samples. There was a significant correlation between HIF-1α and VEgF-C （P = 0.014, r = 0.273, Spearman＇s coefficient of correlation）. HIF-1α and VEgF-C overexpression was significantly correlated with higher LVD （P = 0.003 and P = 0.017, re- spectively）, regional lymph nodal involvement （P = 0.002 and P = 0.004, respectively） and advanced tumor, node, metastasis （TNM） classification （P = 0.001 and P = 0.01, respectively）. Higher MVD was observed in the group expressing higher levels of HIF-1α and VEgF-C （P = 0.033 and P = 0.037, respectively）. Univariate analysis showed shorter survival time in patients expressing higher levels of HIF-1α and VEgF-C. HIF-1α was also found to be an independent prognostic factor of overall survival in multivariate analysis. The results suggest that HIF-1α may affect VEgF-C expression, thus acting as a crucial regulator of lymphangiogenesis and angiogenesis in breast cancer. This study highlights promising potential of HIF- 1α as a therapeutic target against tumor lymph node me- tastasis.

关键词： HIF-1α VEgF-C lymphangiogenesis angiogenesis breast cancer

Identification of MBF2 family genes in Bombyx mori and their expression in different tissues and stages and in response to Bacillus bombysepticus infection and starvation

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Insect Science 2016年第4期23卷 502-512页

作者： Chun-Yan Zhou Xing-Fu zha Chun Liu Min-Jin han Li-Ying zha.g Pan-Pan Shi He Wang Ren-Wen Zheng Qing-You xia State Key Laboratory of Silkworm genome Biology Southwest University Chongqing China

The Multiprotein bridge factor 2 （MBF2） gene was first identified as a coactivator involved in BmFTZ-F 1-mediated activation of the Fushi tarazu gene. Herein, nine homologous genes of MBF2 gene are identified. Evolutionary analysis showed that this gene family is insect-specific and that the family members are closely related to response to pathogens （REPAT） genes. Tissue distribution analysis revealed that these genes could be expressed in a tissue-specific manner. Developmental profiles analysis showed that the MBF2 gene family members were highly expressed in the different stages. Analysis of the expression patterns of nine MBF2 family genes showed that Bacillus bombysepticus treatment induced the up-regulation of several MBF2 family genes, including MBF2-4, -7, -9, -8. Furthermore, we found the MBF2 family genes were modulated by starvation and the expression of these genes recovered upon re-feeding, except for MBF2-5, -9. These findings suggested roles for these proteins in insect defense against pathogens and nutrient metabolism, which has an important guiding significance for designing pest control strategies.

关键词： immunity nutrient metabolism physiology whole-genome scanning

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基于监测数据的电磁频谱地图构建与验证

国防科技大学学报 2023年第3期45卷 171-178页

作者：查淞夏海洋黄纪军刘继斌马晨李冰国防科技大学电子科学学院湖南长沙410073 中国人民解放军32035部队陕西西安710060 中国人民解放军31007部队北京100000

提出基于广义回归神经网络拟合和聚类克里金的构建方法,通过趋势面拟合,将电磁频谱地图构建分解为路径衰减和阴影衰落分量的估计问题,以提升构建精度;设计监测数据聚类和自适应最优邻域选取机制,在保证构建精度的条件下减小计算数据量,... 详细信息

提出基于广义回归神经网络拟合和聚类克里金的构建方法,通过趋势面拟合,将电磁频谱地图构建分解为路径衰减和阴影衰落分量的估计问题,以提升构建精度;设计监测数据聚类和自适应最优邻域选取机制,在保证构建精度的条件下减小计算数据量,以提升构建速度,从而利用数量有限的电磁环境监测数据,在不需要先验信息的条件下实现电磁频谱地图的准确、快速构建。设计并实现电磁频谱地图验证系统,搭建车载数据采集设备,利用实测电磁环境监测数据,验证所提方法的可行性及构建性能。

关键词：电磁频谱地图电磁环境监测数据广义回归神经网络聚类克里金实测数据