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101.
Which studies, theories, and ideas have influenced Eugene Garfield’s scientific work? Recently, the method reference publication year spectroscopy (RPYS) has been introduced, which can be used to answer this and related questions. Since then, several studies have been published dealing with the historical roots of research fields and scientists. The program CRExplorer (http://www.crexplorer.net) was specifically developed for RPYS. In this study, we use this program to investigate the historical roots of Eugene Garfield’s oeuvre. 相似文献
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Olga Porembskaya Vsevolod Zinserling Vladimir Tomson Yana Toropova Eleonora A. Starikova Vitaliy V. Maslei Nika I. Bulavinova Olga V. Kirik Marina A. Syrtsova Leonid Laberko Maxim I. Galchenko Vyacheslav Kravchuk Sergey Saiganov Alexander Brill 《International journal of molecular sciences》2022,23(10)
Pulmonary embolism is a life-threatening condition, which can result in respiratory insufficiency and death. Blood clots occluding branches of the pulmonary artery (PA) are traditionally considered to originate from thrombi in deep veins (usually in legs). However, growing evidence suggests that occlusion of the vessels in the lungs can develop without preceding deep vein thrombosis (DVT). In this work, we used an inferior vena cava (IVC) complete ligation model of DVT in Wistar rats to explore the possibility and mechanisms of PA thrombosis under the conditions where all routes of thrombotic mass migration from peripheral veins are blocked. We demonstrate that rats both with normal and reduced neutrophil counts developed thrombi in the IVC, although, neutropenia caused a substantial decrease in thrombus size and a shift from fresh fibrin toward mature fibrin and connective tissue inside the thrombus. Massive fibrin deposition was found in the PA branches in the majority of DVT rats with normal neutrophil counts, but in none of the neutropenic animals. Neutrophil ablation also abolished macroscopic signs of lung damage. Altogether, the results demonstrate that thrombi in the lung vasculature can form in situ by mechanisms that require local neutrophil recruitment taking place in the DVT setting. 相似文献
103.
环境监测工作是生态环境保护中的重要组成内容,石化园区环境监测是完善监测制度,利用现代最新监测和分析手段,对空间环境中污染物的浓度与特征实施分析,为园区环境保护工作提供所需要的数据信息。本文重点阐述石化园区环境监测在生态环境保护中的重要作用,以及环境监测管理对策与石化园区生态环境保护之间的重要关系。 相似文献
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采用界面聚合法合成了聚(1-萘胺)纳米颗粒.利用红外光谱(FT-IR),紫外可见吸收光谱(UV-vis),电子扫描显微镜(SEM),投射电镜(TEM),X射线衍射(XRD),循环伏安(cyclic voltammogram)等测试方法,对聚合物进行了表征并对聚合物形貌、结构及性能进行了初步探讨.结果表明,界面聚合法合成的聚(1-萘胺)呈现直径在100nm内的颗粒状分布;XRD结果显示,聚(1-萘胺)为半结晶态聚合物;界面聚合法合成的聚(1-萘胺)具有一定的电化学活性. 相似文献
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Soil moisture is important information in semiarid rangelands where vegetation growth is heavily dependent on the water availability. Although many studies have been conducted to estimate moisture in bare soil fields with Synthetic Aperture Radar (SAR) imagery, little success has been achieved in vegetated areas. The purpose of this study is to extract soil moisture in sparsely to moderately vegetated rangeland surfaces with ERS-2/TM synergy. We developed an approach to first reduce the surface roughness effect by using the temporal differential backscatter coefficient (Δσwet-dry0). Then an optical/microwave synergistic model was built to simulate the relationship among soil moisture, Normalized Difference Vegetation Index (NDVI) and Δσwet-dry0. With NDVI calculated from TM imagery in wet seasons and Δσwet-dry0 from ERS-2 imagery in wet and dry seasons, we derived the soil moisture maps over desert grass and shrub areas in wet seasons. The results showed that in the semiarid rangeland, radar backscatter was positively correlated to NDVI when soil was dry (mv<10%), and negatively correlated to NDVI when soil moisture was higher (mv>10%). The approach developed in this study is valid for sparse to moderate vegetated areas. When the vegetation density is higher (NDVI>0.45), the SAR backscatter is mainly from vegetation layer and therefore the soil moisture estimation is not possible in this study. 相似文献
110.
主要讨论基于Web应用程序的潜在安全问题。首先阐述Web系统的漏洞,建立Web应用程序安全意识的必要性及应用程序存在的威胁以及相应对策;接着讨论一些可能存在的安全风险;最后给出对Web应用程序开发者和系统管理员的一些建议。 相似文献