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关键词： 全自动尿沉渣分析仪   尿沉渣检验   效果  

摘要： 目的:探讨用全自动尿沉渣分析仪进行尿沉渣检验的作用。方法:选择2018年3月~2019年3月本院检验科收治的进行尿沉渣检验的120例尿液标本作为研究对象,所有标本实施显微镜检查、全自动尿沉渣分析仪检查,以镜检结果作为诊断标准,分析两种方法的检验结果。结果:显微镜检管型阳性为12例,红细胞阳性为45例,白细胞阳性为36例。全自动尿沉渣分析仪管型阳性20例,检验假阳性为7.41%,检验精准度为92.59%;红细胞阳性49例,检验假阳性为5.33%,检验精准度为93.42%,白细胞阳性40例,检验假阳性为4.76%,检验精准度95.24%。结论:运用全自动尿沉渣分析仪检验尿沉渣,有着较高精准度,却可能有假阳性现象。所以,在尿沉渣检验中,应当镜检联合全自动尿沉渣分析仪,提升诊断精准度。

摘要： In this study, we investigated the possibility of using an artificial neural network (ANN) to classify human hair samples according to pigment (original or bleached hair) and sex (female or male) from numerical data obtained by wavelength dispersive X-ray fluorescence (WDXRF) and by laser-induced breakdown spectroscopy (LIBS). The results were promising, showing that the developed ANNs are able to classify the pigment and donor sex of hair samples with 100% and 89.5% accuracy, respectively, in the test set using WDXRF data. For the LIBS data in the test set, 100% of the pigment classifications were correct, and 78.9% of the donor sex classifications were correct.

关键词： mobile app   empathy   emotion   affect   skin conductance   physiological activation   mobile learning   LGBTQ   queer history  

摘要： Mobile apps take advantage of the ubiquity of mobile phones and can be used to share unique pedagogical experiences with multimedia content not yet available in curriculums. This preliminary study used a quasi-experimental pretest-posttest design to examine changes in self-reported empathy toward sexual orientation and gender identity (SOGI) minority people. We also report on the associations between gender and a physiological measure of emotional activation, skin conductance level (SCL), on self-reported empathy. The main results of this study that examined 57 undergraduate students at a Canadian University whom interacted with a queer history app individually were the following: Preliminary evidence that (1) students' empathy toward SO and GI minorities can be measured using a modified version of the Scale of Ethnocultural Empathy (SEE). (2) Statistically significant increases in empathy toward SO and GI minorities pre to post app interaction. (3) Students' pre- and post-empathy levels were statistically significantly higher toward SO than GI minorities. (4) Female students had statistically significantly higher self-reported empathy toward SO and GI minorities than males. (5) Male students had statistically significantly higher SCL than females. (6) Statistically significant interaction between SCL grouping and questionnaire administration on GI minority empathy. Findings and implications are discussed in lieu of the contributions that mobile apps can play to support social change, in particular, by fostering empathy.

关键词： Carbon fibres   Adhesion   Fibre/matrix bond   Micromechanics  

摘要： It is commonly assumed that a higher oxygenated content on the surface of carbon fibers will lead to high interfacial adhesion. Thus, carbon fibers are exposed to oxidizing treatments to increase surface polarity. Here, we examine the interfacial interactions of a range of thermoset and thermoplastic polymers with carbon fibers that have a grafted polyethylene oxide (PEO) chains to their surface. This provides an extremely hydrophilic surface, without potential degradation of the fiber via chemical oxidation. We find that high surface polarity does not always correlate to high interfacial adhesion;in some instances, unsized hydrophobic carbon fibers possess equal or better fiber-to-matrix adhesion than treated hydrophilic carbon fibers. The most notable example is in vinyl ester resin, in which the presence of an alkyne group, able to participate in the radical polymerization process, provides significant improvements in interfacial shear strength (IFSS) compared to a larger, and polar, PEO chain.

关键词： Normal discrimination   Semi-supervised learning   Model for missing-class labels   Relative efficiency of classifiers  

摘要： There has been increasing interest in using semi-supervised learning to form a classifier. As is well known, the (Fisher) information in an unclassified feature with unknown class label is less (considerably less for weakly separated classes) than that of a classified feature which has known class label. Hence in the case where the absence of class labels does not depend on the data, the expected error rate of a classifier formed from the classified and unclassified features in a partially classified sample is greater than that if the sample were completely classified. We propose to treat the labels of the unclassified features as missing data and to introduce a framework for their missingness as in the pioneering work of Rubin (Biometrika 63:581-592, 1976) for missingness in incomplete data analysis. An examination of several partially classified data sets in the literature suggests that the unclassified features are not occurring at random in the feature space, but rather tend to be concentrated in regions of relatively high entropy. It suggests that the missingness of the labels of the features can be modelled by representing the conditional probability of a missing label for a feature via the logistic model with covariate depending on the entropy of the feature or an appropriate proxy for it. We consider here the case of two normal classes with a common covariance matrix where for computational convenience the square of the discriminant function is used as the covariate in the logistic model in place of the negative log entropy. Rather paradoxically, we show that the classifier so formed from the partially classified sample may have smaller expected error rate than that if the sample were completely classified.

关键词： Assortment planning   Category evolution   Long tail theory   Niche products   Pareto rule   Retailing  

摘要： Long tail theory, the notion that the future of retailing could involve shifting product assortments to offer more product variety to precisely serve the unique needs of individual customers, has largely been proven true in the context of online distribution. However, it has been implicitly assumed that this theory does not apply to brick-and-mortar selling situations due to higher supply side inventory costs and higher demand side consumer search costs. Academics and practitioners alike have thus advocated for the use of Pareto rules to make category assortment planning decisions about product inventory breadth and depth in the brick-and-mortar channel. This research directly challenges this received wisdom by noting that the widespread prevalence and use of mobile technology is causing information flows to speed up for consumers even while performing traditional shopping tasks. Such information flows should theoretically favor the strategic importance of niche products in the long tail of the sales distribution. A large-scale empirical analysis of consumer packaged goods brick-and-mortar retailing data indicates that this alternative prediction is indeed true. This research contributes to a larger body of research as well that has documented how major environmental forces are shifting the nature of retail strategy, particularly in the brick-and-mortar channel.

关键词： 血液分析仪   急性白血病   慢性白血病   检验  

摘要： 研究急慢性白血病患者采取血液分析仪检验的应用价值。方法 于本院收治的急慢性白血病患者中选取60例,时间选为2019年1月~2020年1月。其中有30例为急性白血病患者为实验组,30例为慢性白血病患者为研究组,同期选择30例体检正常健康者作为对照组,使用血液分析仪对三组进行检测,对比检测结果。结果 与对照组相比,实验组与研究组血红蛋白指标均较低,白细胞指标较高,研究组血红蛋白、白细胞指标均高于实验组,与对照组血小板指标对比,实验组较低,研究组较高,三组血红蛋白、白细胞以及血小板指标对比有差异(P<0.05)。结论 对急慢性白血病患者给予血液分析仪检测具有重要的应用价值,可明确反映出急慢性白血病患者临床重要指标,进而为患者诊断提供有利的理论依据,值得借鉴。

关键词： Internet monitoring   Policy satisfaction   Intrinsic work motivation   Affective organizational commitment   Field experiment  

摘要： Purpose Internet monitoring in organizations can be used to monitor risks associated with Internet usage and information systems in organizations, such as employees' cyberloafing behavior and information security incidents. Extant research has mainly discussed the effect of Internet monitoring in achieving the targeted goals (e.g. mitigating cyberloafing behavior and information security incidents), but little attention has been paid to the possible side effects of Internet monitoring. Drawing on affective events theory, the authors attempt to reveal that Internet monitoring may cause side effects on employees' Internet usage policy satisfaction, intrinsic work motivation and affective organizational commitment. Design/methodology/approach The authors conducted a field experiment in a software development company. In total, 70 employees participated in the study. Mann-WhitneyUtest was employed to analyze the data. Findings The results suggest that Internet monitoring decreased employees' satisfaction with the Internet usage policy, intrinsic work motivation, as well as affective organizational commitment. Originality/value This study contributes to the literature by examining the side effects of Internet monitoring on employees. It also has implications for organizations to make appropriate decisions regarding whether to implement Internet monitoring.

关键词： Rooftop unit   Fault detection and diagnosis   Data-driven   Machine learning   Classification  

摘要： This paper proposes and demonstrates a data-driven fault detection and diagnosis strategy for packaged rooftop units using statistical machine learning classification methods. The fault detection and diagnosis task is formulated as a multi-class classification problem. Seven typical rooftop unit faults are discriminated against one another as well as the normal condition. Since experimental data for rooftop units is rare and difficult to obtain, a simulated data library of model faults at steady state operation is used for training and validating the classifications models. Synthetic minority over-sampling technique is used to generate new artificial samples of minority class in order to balance the dataset. Nine well-known classification methods are applied to our dataset, and their performance is compared. The results show that support vector machine, with an overall accuracy rate of 96.2%, is the best classifier, and linear discriminant analysis, with an overall accuracy rate of 76.2%, is the worst classifier. The performance of the classification methods for individual faults is also characterized using true positive rate and false positive rate statistical measures. The relative importance of input variables is also discussed. The high accuracy of the classification methods shows the potential of a data-driven strategy in detecting and diagnosing the rooftop unit faults. (C) 2020 Elsevier B.V. All rights reserved.

摘要： Motivation: Single-molecule force spectroscopy (SMFS) experiments pose the challenge of analysing protein unfolding data (traces) coming from preparations with heterogeneous composition (e.g. where different proteins are present in the sample). An automatic procedure able to distinguish the unfolding patterns of the proteins is needed. Here, we introduce a data analysis pipeline able to recognize in such datasets traces with recurrent patterns (clusters). Results: We illustrate the performance of our method on two prototypical datasets: similar to 50 000 traces from a sample containing tandem GB1 and similar to 400 000 traces from a native rod membrane. Despite a daunting signal-to-noise ratio in the data, we are able to identify several unfolding clusters. This work demonstrates how an automatic pattern classification can extract relevant information from SMFS traces from heterogeneous samples without prior knowledge of the sample composition.