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Lymphocyte dysregulation in coronavirus disease-19 (COVID-19) is a major contributing factor linked to disease severity and mortality. Apoptosis results in the accumulation of cell-free DNA (cfDNA) in circulation. COVID-19 has a heterogeneous clinical course. The role of cfDNA levels was studied to assess the severity and outcome of COVID-19 patients and correlated with other laboratory parameters. The current case series included 100 patients with mild COVID-19 (MCOV-19) and 106 patients with severe COVID-19 (SCOV-19). Plasma cfDNA levels were quantified using SYBR green quantitative real-time PCR through amplification of the β-actin gene. CfDNA level was significantly higher in SCOV-19 at 706.7 ng/ml (522.6–1258) as compared to MCOV-19 at 219.8 ng/ml (167.7–299.6). The cfDNA levels were significantly higher in non-survivor than in survivors (p = 0.0001). CfDNA showed a significant correlation with NLR, ferritin, LDH, procalcitonin, and IL-6. The diagnostic sensitivity and specificity of cfDNA in the discrimination of SCOV-19 from MCOV-19 were 90.57% & 80%, respectively. CfDNA showed a sensitivity of 94.74% in the differentiation of non-survivors from survivors. CfDNA levels showed a significant positive correlation with other laboratory and inflammatory markers of COVID-19. CfDNA levels, NLR, and other parameters may be used to stratify and monitor COVID-19 patients and predict mortality. CfDNA may be used to predict COVID-19 severity with higher diagnostic sensitivity.  相似文献   
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When examined carefully, it is seen that there is not an available and detailed cttrriculum designed for the aim of foreign language teaching with integrated cultural items of the target language in the programs of the schools under authority of the Ministry of Education and Turkish higher education institutions. In recent years, the specialists have an agreement on the issue that foreign language instruction should be carried out by the means of target language's history, literature, geography and also its social characteristics. The idiom "it's raining cats and dogs" can be misinterpreted by a Turkish student without the knowledge of this idiom's story in English history as "Cats and dogs are pouring down from the sky". An important French architectural building "Saint Mary Cathedral, Notre Dame de Paris" can be misunderstood as "Our Parisian Woman" by a student who is unfamiliar with French culture. Both examples show that encountered foreign words and phrases can be misunderstood and mostly these words are perceived and interpreted according to learners' own cultural figures. The aims of this study are to show the significance of culture-based foreign language courses and to make a contribution to the literature by regarding the views of researchers beheving that culture and language are inseparable concepts. In this context, Erzincan University French Language Teaching Department students' opinions on the relation between culture and language learning were received with the application of qualitative structured written response method. Then, document analysis of written comments was evaluated. Consequently, the analysis on the participants' written comments showed that a culture integrated foreign language course can make positive contributions to students' learning, language learning process and learning environment.  相似文献   
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A systems-based classroom intervention on environmental education was designed for seventh grade students; the results were evaluated to see its impact on the development of systems thinking skills and standard science achievement and whether the systems approach is a more effective way to teach environmental issues that are dynamic and complex. A quasi-experimental methodology was used to compare performances of the participants in various dimensions, including systems thinking skills, competence in dynamic environmental problem solving and success in science achievement tests. The same pre-, post- and delayed tests were used with both the comparison and experimental groups in the same public middle school in Istanbul. Classroom activities designed for the comparison group (N = 20) followed the directives of the Science and Technology Curriculum, while the experimental group (N = 22) covered the same subject matter through activities benefiting from systems tools and representations such as behaviour over time graphs, causal loop diagrams, stock-flow structures and hands-on dynamic modelling. After a one-month systems-based instruction, the experimental group demonstrated significantly better systems thinking and dynamic environmental problem solving skills. Achievement in dynamic problem solving was found to be relatively stable over time. However, standard science achievement did not improve at all. This paper focuses on the quantitative analysis of the results, the weaknesses of the curriculum and educational implications.  相似文献   
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Modeling of D-STATCOM in distribution systems load flow   总被引:1,自引:0,他引:1  
This paper presents modeling of Distribution STATCOM (D-STATCOM) in load flow calculations for the steady- state voltage compensation. An accurate model for D-STATCOM is derived to use in load flow calculations. The rating of this device as well as the direction of required reactive power injection for voltage compensation in the desired value (1 p.u.) is de- rived and discussed analytically and mathematically by the phasor diagram method. Furthermore, an efficient method for node and line identification used in load flow calculations is presented. The validity of the proposed model is examined by using two standard distribution systems consisting of 33 and 69 nodes, respectively. The best location of D-STATCOM for under voltage problem mitigation approach in the distribution networks is determined. The results validate the proposed model for D- STATCOM in large distribution systems.  相似文献   
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High-throughput, cost-effective, and portable devices can enhance the performance of point-of-care tests. Such devices are able to acquire images from samples at a high rate in combination with microfluidic chips in point-of-care applications. However, interpreting and analyzing the large amount of acquired data is not only a labor-intensive and time-consuming process, but also prone to the bias of the user and low accuracy. Integrating machine learning (ML) with the image acquisition capability of smartphones as well as increasing computing power could address the need for high-throughput, accurate, and automatized detection, data processing, and quantification of results. Here, ML-supported diagnostic technologies are presented. These technologies include quantification of colorimetric tests, classification of biological samples (cells and sperms), soft sensors, assay type detection, and recognition of the fluid properties. Challenges regarding the implementation of ML methods, including the required number of data points, image acquisition prerequisites, and execution of data-limited experiments are also discussed.  相似文献   
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This study compared uses of U.S. television by foreign children residing in the U.S. and their American counterparts in light of theories of acculturation, cultivation, and uses and gratifications. Compared with U.S. children, foreign children: used television more for learning purposes, were relatively more interested in television programs, spent more time watching television, identified more frequently with television characters, and expressed stronger beliefs in the social reality portrayed by television.  相似文献   
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