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31.
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   
32.
The aim of this study was to examine the possibility of obtaining information about the heart rate and physiological load imposed on soccer players during a game. The study was conducted on 27 soccer players, 9 each from semi-professional, university and recreational soccer teams. Players from all positions (attack, midfield and defence) were selected for the study. Each subject's heart rate was monitored during a match using a short-range radio telemetry (Sport Tester PE3000), and was sampled at 5-s intervals. The results indicate that it is possible to monitor successfully the heart rate of players with such equipment. The mean heart rate and standard deviation for each player during match play were: semi-professional players (172 +/- 12, 176 +/- 9 and 166 +/- 15 for forwards, midfielders and defenders, respectively); university players (171 +/- 13, 173 +/- 10 and 156 +/- 13 for forwards, midfielders and defenders, respectively); and recreational players (173 +/- 13, 170 +/- 12 and 162 +/- 13 for forwards, midfielders and defenders, respectively). Analysis by playing position revealed that midfield and forward players has a greater mean heart rate during a game than defensive players. To examine the suitability and accuracy of the two methods of obtaining objective data on heart rate, comparisons were made between the Sport Tester PE3000 and a standard electrocardiograph (ECG) telemetry technique. The results show that both techniques produce similar results; the former was the more convenient.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
33.
Discussions of the quality of learning in university education often focus on curricula. Less attention is paid to the role of student–staff interactions. In a context in which a host of factors place pressure on the opportunities for students and staff to interact, it is important to use empirical insights to inform decisions about how to optimise learning. This paper uses data from a large survey of students and teaching staff in Australia to suggest that students and staff should be regarded as allies in learning. It investigates student reports to suggest that frequent interactions with those who teach them lead to higher levels of student engagement and satisfaction and lower attrition rates. The advantages do not only flow in one direction. Teaching staff gain insights into students' learning experiences, providing them with clues to better target their teaching.  相似文献   
34.
The purpose of the paper is to explore Students' perception of university teaching behaviours in Pakistan. Three hundred and fifty students from the six public sector Pakistani universities returned questionnaires. Assessment framework, learning activities and instructional strategies emerged from factor analysis as common factors. Students' views on five conceptual variables were also analysed: instructional design, active teaching, learning activities, questioning styles; and assessment framework. University teaching in Pakistan was found to be driven by assessment. This is a matter of concern for all stake holders, including the administration of the universities, teachers, students and the Higher Education Commission. A teaching behaviour paradigm shift is required, switching from knowledge-oriented teaching behaviour focused on successful passage through assessment, to teaching behaviour focused upon the development of transferable skills demanded by external markets.  相似文献   
35.
Although Richard Rorty's controversial thought has been the subject of many works, there has not been much discussion about his approach to cultural difference. The purpose of this article is to examine how Rorty sees cultural differences philosophically and how he deals with them politically. For him, rationality, morality and even the scope of moral responsibility towards others are defined in terms of solidarity with a particular community and ‘ethnocentrism’, rather than in terms of a universal and metaphysically derived set of criteria. It can be argued that since language, language games and values are mainly components of culture, the latter is one of the most significant communities with which Rorty is concerned, though he is not explicit about it. Nevertheless, Rorty does not think that the moral and philosophical significance of communities, particularly cultural communities, should be reflected in politics. The main argument of the article is that there is an unresolved tension in Rorty's thought between philosophical, moral and emotional attribution of significance to communities and arguably cultural communities, and a disregard for them in the political sphere. This paves the way for outlining an approach to cultural difference that is more just and even more in harmony with Rorty's own philosophy.  相似文献   
36.
Forty-six Streptomyces strains were isolated from paintings and stone surfaces from Tell Basta and Tanis tombs (80 km south-east Cairo, Egypt). Eight of these strains were selected to determine their sensitivity against 13 antibiotics. In general, high levels of resistance could be observed. Gentamycin, spiramycin and doxycycline were the most effective antibiotics against the majority of strains under study. Due to the observed antibiotic resistances, gamma irradiation was studied as a possible alternative to inhibit microbial growth. Isolated bacteria were exposed to different doses of gamma irradiation (5, 10, 15, 20 and 25 kGy). The growth of all Streptomyces isolates except S. canarius was completely inhibited at 25 kGy. The applied doses of gamma irradiation did not cause any observable alterations or colour changes to pigments and binding media (arabic gum, animal glue and egg-yolk) used in the paintings.  相似文献   
37.
Mismatched uncertainty and chattering appear as two challenges in sliding mode control. To overcome the problem of mismatched uncertainty, multiple sliding surfaces with virtual inputs are proposed. Accordingly, we have proposed two new methods based on designed neural observer: sliding mode control (SMC) and dynamic sliding mode control (DSMC) methods. Although, the proposed SMC can significantly cope with the mismatched uncertainties, but it suffers from chattering phenomenon. The chattering problem can be removed in DSMC, because an integrator is placed before the system. This results in increased number of the system states. This new state can be identified with the proposed neural observer. Note that in both proposed approaches, the robust performance (invariance property) of system is reserved, even in the presence of mismatch uncertainties. Then, to have a valid comparison the proposed DSMC is also designed using loop transfer recovery observer (LTRO). This comparison shows the good performance of the DSMC based neural networks. Moreover, the upper bound of uncertainties is not used in SMC and DSMC controllers and also in the neural observer and LTRO, which is important in practical implementation. Finally, comparing the equations, one can see the simplicity of DSMC in concept and also in realization.  相似文献   
38.
This paper deals with the leader-following consensus problem of multi-agent systems with the consideration that each agent can only transmit its position state to the neighbors at irregular discrete sampling times. In the proposed algorithm, a continuous-discrete time observer is designed for the continuous estimation of both position and velocity from the discrete position information of the neighbors. These estimated states are then used for designing a continuous control law which solves the leader-following consensus problem. Moreover, the dynamics of the leader is not fixed and can be controlled through an external input. The stability analysis has been carried out by employing the Lyapunov approach which provides sufficient conditions to tune the parameters according to the maximum allowable sampling period. The developed algorithm has been simulated and then tested on an actual multi-robot system consisting of three differential drive wheeled robots. Both simulation and hardware results validate the effectiveness of the control algorithm.  相似文献   
39.
从十多年证券市场的发展历程来看,股权筹资处于主导地位,而债权筹资不足.近几年衍生金融工具筹资有了一些新的发展,如可转债、权证、资产支持证券等,为上市公司筹资提供了更多可供选择的筹资渠道体系.2000年以后股权筹资金额逐年下降,债权筹资逐年上升,资本结构逐步趋于合理.全流通后,上市公司的筹资市场环境将发生巨大的变化,企业的筹资成本与风险也会发生很大的变化,股权筹资稀释控制权的后果将会显现出来,负债筹资的优势也会更加明显.上市公司应充分利用不同筹资工具的优势和特色,降低企业的资金成本和筹资风险,优化资本结构.  相似文献   
40.
团学活动在高职生关键能力培养中的拓展作用   总被引:1,自引:0,他引:1  
在比较、分析关键能力内涵的基础上,指出应很好地重视和发挥团学活动在高职生关键能力培养中作用,并结合实际提出通过团学活动培养和提高高职生关键能力应遵循的四条原则。  相似文献   
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