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71.
Abstract

Winding up the estate of somebody is a sad task, only sustained by the hope of unexpected finds or definitive proof of one's preconceived opinions. There is no difference in this between one's own grandmother and a contemporary like Lucia Moholy. While executing this task I naturally came across various documents that shifted my vague assumptions about this versatile woman in different directions. I saw photographs from her private life that enlightened me about her social relations but, in the end, I was disappointed at not havlng been able to get closer to a person I thought I knew quite well, even if from a certain distance.1  相似文献   
72.
73.
制备了三种氟锆酸钾(K2ZrF6)盐混合物(M),分别在三个温度下将三种盐混合物加入到铸态Mg-3Y-3.5Sm-2Zn合金中。通过差热分析(DSC),X射线衍射(XRD),光学显微镜(OM),扫描电子显微镜(SEM),能量色散谱(EDS)和拉伸试验研究了合金的显微组织和力学性能,讨论了K2ZrF6盐混合物在合金中的晶粒细化机理。结果表明,铸态Mg-3Y-3.5Sm-2Zn合金由α-Mg,Mg12(Y,Sm)Zn 和 (Mg,Zn)3(Y,Sm)三种相组成。SEM和XRD检测发现,添加K2ZrF6盐混合物不会在合金中产生新的相。在780°C下加入M3盐(60wt% K2ZrF6-20wt% NaCl-20wt% KCl)时,合金的晶粒细化效果最佳。通过在780℃下加入三种盐,铸态Mg-3Y-3.5Sm-2Zn合金的力学性能得到提高,由M3盐细化后的合金具有最佳的力学性能。K2ZrF6盐混合物可细化铸态Mg-3Y-3.5Sm-2Zn合金,这是由于Mg和K2ZrF6之间还原反应得到的细Zr质点和富锆区在合金中起到的晶粒细化作用。  相似文献   
74.
The assessment of wine traceability and authenticity is a major concern that has gained a lot of interest internationally since the wine has always been subjected to various fraudulent practices. Practiced since ancient times, wine fraud has become more sophisticated in the present day, taking many forms. Consumers, regulatory bodies and manufacturers are all interested to have reliable analytical tools and information to allow the authentication and detection of wine adulteration or incorrect labelling. This research study evaluates and proposes a possible strategy for the detection of adulterated sweet or medium sweet red table wines using appropriate chemical parameters which can reveal prohibited practices in the winemaking process. The work is performed on 29 table wine samples, bought from the market, packed in PET bottles. Exogenous addition of sugar and water in the counterfeited table red wines was detected by the measurement of stable isotopes content (δ13C and δ18O) known as origin markers and supplementary confirmed by other classical parameters, as the alcoholic strength of the wines (‰ vol.) and the presence of 5-(hydroxymethyl)-2-furaldehyde (HMF) and of synthetic sweeteners or synthetic red dyes used to correct deficiencies of taste and colour. Additionally, the nature and profile of anthocyanins, as indicator of the red colour of wine, was investigated in the table wines and then compared with that of authentic wines obtained by microvinification of Vitis vinifera, in order to determine their authenticity.  相似文献   
75.
针对现有图形模糊聚类算法合理性差和抗噪能力弱的问题,提出嵌入对称正则项的图形模糊聚类鲁棒算法。将样本聚类所对应的中立度与拒分度相结合构造对称正则项,嵌入现有图形模糊聚类所对应的目标函数;同时,利用像素邻域所对应的均值信息辅助当前像素聚类并构造了空间信息约束正则项,采用拉格朗日乘子法获得正则化图形模糊聚类鲁棒分割算法。不同噪声干扰图像分割结果表明,所建议的分割算法是有效的,相比现有的鲁棒模糊聚类分割算法具有更强的抑制噪声能力。  相似文献   
76.
One of the most accurate types of prototype selection algorithms, preprocessing techniques that select a subset of instances from the data before applying nearest neighbor classification to it, are evolutionary approaches. These algorithms result in very high accuracy and reduction rates, but unfortunately come at a substantial computational cost. In this paper, we introduce a framework that allows to efficiently use the intermediary results of the prototype selection algorithms to further increase their accuracy performance. Instead of only using the fittest prototype subset generated by the evolutionary algorithm, we use multiple prototype subsets in an ensemble setting. Secondly, in order to classify a test instance, we only use prototype subsets that accurately classify training instances in the neighborhood of that test instance. In an experimental evaluation, we apply our new framework to four state-of-the-art prototype selection algorithms and show that, by using our framework, more accurate results are obtained after less evaluations of the prototype selection method. We also present a case study with a prototype generation algorithm, showing that our framework is easily extended to other preprocessing paradigms as well.  相似文献   
77.
78.
The PI3K/Akt/mTOR pathway plays an essential role in a wide range of biological functions, including metabolism, macromolecular synthesis, cell growth, proliferation and survival. Its versatility, however, makes it a conspicuous target of many pathogens; and the consequential deregulations of this pathway often lead to complications, such as tumorigenesis, type 2 diabetes and cardiovascular diseases. Molecular targeted therapy, aimed at modulating the deregulated pathway, holds great promise for controlling these diseases, though side effects may be inevitable, given the ubiquity of the pathway in cell functions. Here, we review a variety of factors found to modulate the PI3K/Akt/mTOR pathway, including gene mutations, certain metabolites, inflammatory factors, chemical toxicants, drugs found to rectify the pathway, as well as viruses that hijack the pathway for their own synthetic purposes. Furthermore, this evidence of PI3K/Akt/mTOR pathway alteration and related pathogenesis has inspired the exploration of computer-aided targeting of this pathway to optimize therapeutic strategies. Herein, we discuss several possible options, using computer-aided targeting, to reduce the toxicity of molecularly-targeted therapy, including mathematical modeling, to reveal system-level control mechanisms and to confer a low-dosage combination therapy, the potential of PP2A as a therapeutic target, the formulation of parameters to identify patients who would most benefit from specific targeted therapies and molecular dynamics simulations and docking studies to discover drugs that are isoform specific or mutation selective so as to avoid undesired broad inhibitions. We hope this review will stimulate novel ideas for pharmaceutical discovery and deepen our understanding of curability and toxicity by targeting the PI3K/Akt/mTOR pathway.  相似文献   
79.
Display pixels of liquid-crystal-display televisions (LCD TVs) on thin-film-transistor (TFT) array are getting smaller. This paper introduced the method of voltage imaging technique, which developed and provides initial insight into the thin-film-transistor array flaw detection and measurement for ultra-high-definition (Ultra HD, UHD) LCD TV application. We proposed the measurement of flaw detection, based on TFT array testing and characterization with respect to opto-electric transformation measurement.  相似文献   
80.
With the proliferation of mobile devices and wireless technologies, location based services (LBSs) are becoming popular in smart cities. Two important classes of LBSs are Nearest Neighbor (NN) queries and range queries that provide user information about the locations of point of interests (POIs) such as hospitals or restaurants. Answers of these queries are more reliable and satisfiable if they come from trustworthy crowd instead of traditional location service providers (LSPs). We introduce an approach to evaluate NN and range queries with crowdsourced data and computation that eliminates the role of an LSP. In our crowdsourced approach, a user evaluates LBSs in a group. It may happen that group members do not have knowledge of all POIs in a certain area. We present efficient algorithms to evaluate queries with accuracy guarantee in incomplete databases. Experiments show that our approach is scalable and incurs less computational overhead.  相似文献   
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