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Computed tomography combined with gastroscopy for assessment of pancreatic segmental portal hypertension

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World Journal of Clinical Cases 2022年第24期10卷 8568-8577页

作者： Yu-Li Wang Han-Wen Zhang fan lin Department of Radiology The First Affiliated Hospital of Shenzhen UniversityHealth Science CenterShenzhen Second People’s HospitalShenzhen 518035Guangdong ProvinceChina

BACKGROUND Pancreatic segmental portal hypertension(PSPH) is the only type of portal hypertension that can be completely cured. However, it can easily cause varicose veins in the esophagus and stomach and hemorrhage in the digestive *** To explore the application of computed tomography(CT) to examine the characteristics of PSPH and assess the risk *** This was a retrospective analysis of CT images of 22 patients diagnosed with PSPH at our center. Spearman correlation analysis was performed using the range of esophageal and gastric varices(measured by the vertical gastric wall), the ratio of the width of the splenic portal vein to that of the compression site(S/C ratio), the degree of splenomegaly, and the stage determined by gastroscopy. This study examined whether patients experienced gastrointestinal bleeding within 2 wk and combined CT and gastroscopy to explore the connection between bleeding and CT *** The range of esophageal and gastric varices showed the best correlation in the diagnosis of PSPH(P < 0.001), and the S/C ratio(P = 0.007) was correlated with the degree of splenomegaly(P = 0.021) and PSPH(P < 0.05). This study revealed that male patients were more likely than females to progress to grade 2 or grade 3 as determined by gastroscopy. CT demonstrated excellent performance, with an area under the curve of *** CT can be used to effectively analyze the imaging signs of PSPH, and CT combined with gastroscopy can effectively predict the risk level of gastrointestinal bleeding.

关键词： Computed tomography Pancreatic segmental portal hypertension esophageal and gastric varices Gastrointestinal bleeding Curable portal hypertension

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青海省自然保护地空间分布及体系重构探讨

自然保护地 2024年第3期4卷 41-53页

作者：范琳刘楠赵力尚帅斌刘娟国家林业和草原局西北调查规划院旱区生态水文与灾害防治国家林业和草原局重点实验室西安710048

【目的】青海保护着“中国水塔”,是我国西部重要的生态安全屏障和高寒生物种质资源库。研究青海以国家公园为主体的自然保护地体系对于国家公园和自然保护地发展改革具有重要意义,也可为当下以国家公园为主体的自然保护地体系建设提供... 详细信息

【目的】青海保护着“中国水塔”,是我国西部重要的生态安全屏障和高寒生物种质资源库。研究青海以国家公园为主体的自然保护地体系对于国家公园和自然保护地发展改革具有重要意义,也可为当下以国家公园为主体的自然保护地体系建设提供借鉴。【方法】以青海省7类95处自然保护地为研究对象,采用最邻近指数、核密度指数、空间叠置等方法分析省域自然保护地空间集聚特征和重叠特征,利用数理统计与ArcGIS空间分析技术识别分析全省自然生态空间,并提出自然保护地体系重构路径。【结果】结果表明,研究区自然保护地面积以国家公园、自然保护区和国家级自然保护地为主,数量上风景名胜区、森林公园、湿地公园占据优势,空间分布上与省域自然地理特征相契合,整体呈聚集分布;不同类型的自然保护地存在交叉重叠,涉及重叠的自然保护地52个,占全省自然保护地总数量的54.74%;提出从新建、撤销、归并、拆分、调整范围等5个方面优化空间布局,优化后青海省自然保护地82个,占全省总面积的41.42%,其中国家公园占80.21%、自然保护区占15.38%、自然公园占4.42%。【结论】实现了以国家公园为主体、自然保护区为基础、各类自然公园为补充的新型自然保护地体系,全省重要的生态系统、生物物种、景观遗迹基本得到了有效保护。

关键词：国家公园自然保护地空间格局体系重构青海省

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基于CiteSpace的中医药治疗下肢缺血性疾病的文献计量学研究

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中国当代医药 2024年第3期31卷 37-43页

作者：蔡晓婷刘娜婷林凡王鹤福建中医药大学中西医结合学院病理生理学实验室中西医结合慢性病研究福建省高校重点实验室中西医结合基础综合实验室福建福州350122

目的探讨中医药治疗下肢缺血性疾病的研究情况,研究该领域的热点与发展趋势。方法检索2012年1月至2022年12月中国知网(CNKI)和科学引文索引数据库(WOS)相关文献,应用CiteSpace软件分析纳入文献的发文量、国家、机构、作者、共被引文献... 详细信息

目的探讨中医药治疗下肢缺血性疾病的研究情况,研究该领域的热点与发展趋势。方法检索2012年1月至2022年12月中国知网(CNKI)和科学引文索引数据库(WOS)相关文献,应用CiteSpace软件分析纳入文献的发文量、国家、机构、作者、共被引文献和关键词等信息并生成知识图谱。结果共纳入1447篇中文文献和58篇英文文献,年发文量总体稳步增长,但中文文献2020年来有所下降。祛腐生新、益气活血等是关键治疗原则,糖尿病足是热点研究病种,中药泡足、穴位按摩等外治方法关注度较高,黄芪和地黄药对以及肉桂醛、阿魏酸、黄芪甲苷等有效成分极受关注,胱硫醚γ裂解酶(CSE)-硫化氢(H2S)-血管内皮生长因子(VEGF)轴以及磷脂酰肌醇3激酶(PI3K)/蛋白激酶B(AKT)和丝裂原活化蛋白激酶(MAPK)信号通路受高度关注。结论当前本领域形成以中国为中心的国际合作网,并逐步发展。但各机构、作者间交流合作不足,需加强。糖尿病足的治疗为研究热点,结果多为临床疗效报道,相关机制值得深入挖掘。

关键词：下肢缺血性疾病中医药文献计量学 CiteSpace

基于经验频率分布的偏态概率模型可靠度计算方法研究

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四川建筑科学研究 2024年第1期50卷 52-59页

作者：冉志红董国华杨子富林帆云南大学建筑与规划学院云南昆明650091

在既有结构可靠度计算中,经验频率分布较容易通过简单的序列计算得到。利用经验频率分布回归得到的正态概率模型或偏态概率模型可以计算相关统计参数、失效概率和可靠指标。大量的计算和比较分析得出,偏态概率模型在工程实践中具有更好... 详细信息

在既有结构可靠度计算中,经验频率分布较容易通过简单的序列计算得到。利用经验频率分布回归得到的正态概率模型或偏态概率模型可以计算相关统计参数、失效概率和可靠指标。大量的计算和比较分析得出,偏态概率模型在工程实践中具有更好的适应性。数值计算结果也进一步表明,用正态分布进行近似,其可靠指标的误差较大,甚至会影响既有结构的评估结果。提出了基于Azzalini偏态分布函数的参数估计方法,并利用失效概率作为联系纽带,建立了偏态分布下失效概率与可靠指标之间的函数关系。以某较为复杂的功能函数为例,展示了所提出的基于经验频率分布的偏态概率模型可靠度计算方法,该方法具有步骤清晰、目标明确、精度较高的优点,能够适用于更加广泛的实际既有工程结构可靠度的评估。

关键词：工程结构可靠度经验频率分布偏态概率模型既有结构评估

Organic Carbon in the Surface Sediments from the Intensive Mariculture Zone of Sanggou Bay: Distribution, Seasonal Variations and Sources

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Journal of Ocean University of China 2019年第4期18卷 985-996页

作者： SUI Juanjuan ZHANG Jihong REN S. Jeffrey lin fan Yellow Sea Fisheries Research Institute Chinese Academy of Fishery Sciences Qingdao 266071 China Function Laboratory for Marine Fisheries Science and Food Production Processes Qingdao National Laboratory for Marine Science and Technology Qingdao 266237 China Function Laboratory for Marine Fisheries Science and Food Production Processes Qingdao National Laboratory for Marine Science and Technology Qingdao 266237 China

Mariculture has rapidly grown worldwide, which might greatly influence the biogeochemical cycle of organic carbon in coastal seas. In this study, several geochemical parameters, including grain size composition, sedimentary total organic carbon (TOC), total nitrogen (TN), stable carbon (δ13C) and nitrogen (δ15N) isotopic compositions, were analyzed for surface sediments collected from different mariculture zones of Sanggou Bay and in different seasons. We investigated the composition and distribution of or- ganic matter in surface sediments and further evaluated the contribution of mariculture activities to TOC sources. The TOC and TN contents (mass percentage) in the bay were in the range of 0.14% to 1.45% and 0.03% to 0.20%, respectively. The spatial distribution indicated that sedimentary TOC and TN contents in shellfish monoculture and shellfish-kelp polyculture zones were higher than in other mariculture zones, which might be related to grain size composition and mariculture organisms. Seasonal variations of TOC contents were observed in different mariculture zones. The TOC/TN atomic ratio (C/N),δ13C and δ15N were in the ranges of 5.97 to 10.97, 21.76‰ to 13.14‰ and 2.13‰ to 8.08‰, respectively, implying that sedimentary organic matter in Sanggou Bay was the mixture of marine phytoplankton, terrestrial and maricultural sources. A simple mixing model based on δ13C was applied and the results indicated that the relative contributions of organic carbon sources in Sanggou Bay followed the order kelp (36.6%) marine phytoplankton (28.7%) shellfish bio-deposition (23.8%) terrestrial input (10.9%). Surface sediments in Sanggou Bay were domi- nated by mariculture-derived organic carbon, which on average accounted for 60.4% of TOC.

关键词： sediment organic carbon sources mariculture Sanggou Bay Iso-Source

The practically renewable and highly efficient electrocatalysts derived from a newly-designed Mo_(8)Pt polyoxometalate compound

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Science China Chemistry 2023年第2期66卷 492-499页

作者： Di Yin Yun-Dong Cao Yi Feng Guang-Gang Gao Hong Liu lin-lin fan Zhen-Hui Kang School of Materials Science and Engineering University of JinanJinan250022China Institute of Functional Nano and Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-based Functional Materials and DevicesSoochow UniversitySuzhou215123China Macao Institute of Materials Science and Engineering(MIMSE) MUST-SUDA Joint Research Center for Advanced Functional MaterialsMacao University of Science and TechnologyTaipaMacao999078China

Platinum(Pt)catalysts are the most practical electrocatalysts;however,their low abundance and high cost severely limit their large-scale *** recovery is a key issue to be resolved before the use of Pt-based electrocatalysts can be broadly ***,the newly designed polyoxometalate[Pt^(II)(NH_(3))_(4)]_(2)[Mo_(8)O26](Mo_(8)Pt)acts as an ideal recycling medium for renewable and highly effective Pt *** from Mo_(8)Pt,by a facile reduction reaction,the formed Pt/Mo_(2)C/Mo_(2)N@C-N electrocatalyst shows superior electrocatalytic activity as compared to commercial Pt/C(20%)under both acidic and alkaline ***,the reaction of Pt/Mo_(2)C/Mo_(2)N@C-N in H_(2)O_(2)solution can regenerate Mo_(8)Pt for Pt *** is also demonstrated that the Pt electrocatalyst can be used for at least five rounds of recycling and regeneration,showing its efficiency and stability as well as its *** work highlights a recycling medium strategy to the new generation of renewable Pt-based catalysts.

关键词： platinum polyoxometalate electrocatalyst recycling-medium renewability

Quantitative evaluation of model consistency evolution in compositional service-oriented simulation using a connected hyper-digraph

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第1期15卷 1-12页

作者： lin-jun fan Yun-xiang linG Xing-tao ZHANG Jun TANG Science and Technology on Information Systems Engineering Laboratory National University of Defense Technology Department of Telecommunications and Systems Engineering Universitat Autónoma de Barcelona

Appropriate maintenance technologies that facilitate model consistency in distributed simulation systems are relevant but generally *** resolve this problem,we analyze the main factors that cause model *** analysis methods used for traditional distributed simulations are mostly empirical and qualitative,and disregard the dynamic characteristics of factor evolution in model operational ***,distributed simulation applications(DSAs)are rapidly evolving in terms of large-scale,distributed,service-oriented,compositional,and dynamic *** developments present difficulty in the use of traditional analysis methods in DSAs,for the analysis of factorial effects on simulation *** solve these problems,we construct a dynamic evolution mechanism of model consistency,called the connected model hyper-digraph(CMH).CMH is developed using formal methods that accurately specify the evolutional processes and activities of models(i.e.,self-evolution,interoperability,compositionality,and authenticity).We also develop an algorithm of model consistency evolution(AMCE)based on CMH to quantitatively and dynamically evaluate influencing *** results demonstrate that non-combination(33.7%on average)is the most influential factor,non-single-directed understanding(26.6%)is the second most influential,and non-double-directed understanding(5.0%)is the least *** previous analysis methods,AMCE provides good feasibility and *** research can serve as guidance for designers of consistency maintenance technologies toward achieving a high level of consistency in future DSAs.

关键词： Model consistency evolution Factor quantification analysis Connected hyper-digraph Formal methods Composi-tional service-oriented simulation

Theoretical Study on the Structural and Electronic Properties of the Reduced SnO_2 (110) Surface

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Chinese Journal of Structural Chemistry 2007年第5期26卷 606-612页

作者： ZHANG Yong-fan lin Wei WANG Qi-Wei LI Yi LI Jun-Qian Department of Chemistry Fuzhou University Fuzhou Fujian 350002 China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

The reduced SnO2（110） surface has been investigated by using first-principles method with a slab model. By examining the vacancy formation energy of three kinds of reduced SnO2（110） surfaces, the most energetically favorable defect surface is confirmed to be the surface with the coexistence of bridging and in-plane oxygen vacancies, which is different with the traditional model by only removing bridging oxygen. The results of band structure calculations indicate that the electronic structure of this defect surface is similar to the SnO surface.

关键词： SnO2(110) surface band structure defect state

Sr_(0.5)Zr_(2)(PO_(4))_(3)-(Ce,Sm)PO_(4)复相陶瓷核废物固化体的制备及化学稳定性

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中国陶瓷 2024年第6期60卷 13-21页

作者：刘缘范林杰刘昆奇刘蝶宋江刘吉王军霞西南科技大学材料与化学学院绵阳621010

为同时固化高放废物中的模拟放射性核素Sr、Ce和Sm,采用一步微波烧结工艺成功制备了Sr_(0.5)Zr_(2)(PO_(4))_(3)-(Ce,Sm)PO_(4)复相磷酸盐陶瓷固化体,采用XRD、Raman、SEM-EDS和密度表征研究了其物相组成、微观结构以及致密性,并利用PC... 详细信息

为同时固化高放废物中的模拟放射性核素Sr、Ce和Sm,采用一步微波烧结工艺成功制备了Sr_(0.5)Zr_(2)(PO_(4))_(3)-(Ce,Sm)PO_(4)复相磷酸盐陶瓷固化体,采用XRD、Raman、SEM-EDS和密度表征研究了其物相组成、微观结构以及致密性,并利用PCT法评估了化学稳定性。结果表明:Sr_(0.5)Zr_(2)(PO_(4))_(3)相和(Ce,Sm)PO_(4)独居石相兼容性好,两相间不发生相互反应;所制备的复相陶瓷固化体晶粒尺寸小,相对密度高于96%,改变Sm/Ce比对固化体的微观结构和致密性无明显影响;PCT测试结果表明Sr、Ce和Sm的元素归一化元素浸出率都较低,与单相磷酸盐陶瓷固化体相比,复相磷酸盐陶瓷固化体具有较为优异的化学稳定性。

关键词： Sr_(0.5)Zr_(2)(PO_(4))_(3)-(Ce Sm)PO_(4)复相陶瓷固化体微波烧结致密性化学稳定性