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51.
The “drug novelty hypothesis” was tested directly by giving rats experience with intraperitoneal injections of ethanol on days prior to avoidance training. This preavoidance experience with ethanol was found to eliminate the prolonged extinction of avoidance responding observed after a single exposure to ethanol. It is suggested that these findings confirm the novelty hypothesis in an active avoidance situation. Possible mechanisms of the drug novelty effect were discussed.  相似文献   
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Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the etiological agent of coronavirus disease-2019 (COVID-19), is a highly contagious pathogenic coronavirus to emerge and spread in human populations. Although substantial exertions have been laid to avert spread of COVID-19 by therapeutic and preventive countermeasures, but emergence of SARS-CoV-2 variants as a result of mutations make the infection more ominous. New viral confers a higher nasopharyngeal viral load, increased viral transmissibility, higher infectiousness, immune escape, increased resistance to monoclonal/polyclonal antibodies from convalescence sera/vaccine, and an enhanced virulence. Thus, it is pertinent to monitor evolving mutations and genetic diversity of SARS-CoV-2 as it is decisive for understanding the viral variants. In this review we provide an overview of colloquial nomenclature and the genetic characteristics of different SARS-CoV-2 variants in the context of mutational changes of the circulating strains, transmissibility potential, virulence and infectivity.  相似文献   
53.
A dual S shaped micro strip antenna with a realistic feed is proposed for generation of tilted beam radiation pattern pertaining for beam steering applications. To achieve this, four feeding points are located at a distance of 5.6 mm from the antenna centre. These feeding points when excited one by one generate four tilted beams in four different space quadrants, thus yielding a beam steerable antenna. Importantly, since the proposed antenna is symmetrical in the structure, all the four tilted beams have the same radiation pattern characteristics. A further enhancement of the antenna bandwidth is also achieved using 100-μm capacitive coupling between the feed and the antenna strip.  相似文献   
54.
The purpose of this study was to validate a wireless network of accelerometers and compare it to a hip-mounted accelerometer for predicting energy expenditure in a semi-structured environment. Adults (n = 25) aged 18–30 engaged in 14 sedentary, ambulatory, exercise, and lifestyle activities over a 60-min protocol while wearing a portable metabolic analyser, hip-mounted accelerometer, and wireless network of three accelerometers worn on the right wrist, thigh, and ankle. Participants chose the order and duration of activities. Artificial neural networks were created separately for the wireless network and hip accelerometer for energy expenditure prediction. The wireless network had higher correlations (r = 0.79 vs. r = 0.72, P < 0.01) but similar root mean square error (2.16 vs. 2.09 METs, P > 0.05) to the hip accelerometer. Measured (from metabolic analyser) and predicted energy expenditure from the hip accelerometer were significantly different for the 3 of the 14 activities (lying down, sweeping, and cycle fast); conversely, measured and predicted energy expenditure from the wireless network were not significantly different for any activity. In conclusion, the wireless network yielded a small improvement over the hip accelerometer, providing evidence that the wireless network can produce accurate estimates of energy expenditure in adults participating in a range of activities.  相似文献   
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A Spiral Task as a Model for In-service Teacher Education   总被引:1,自引:0,他引:1  
The spiral approach has long been used by curriculum designers to deepen students’ knowledge of scientific and mathematical concepts and to bring students to higher levels of abstraction. The benefits of a spiral approach, however, can also be extended to teacher education. This paper describes a spiral activity employed by the Kidumatica program not only to raise the level of teachers’ content knowledge, but also to promote discussion and collaboration among teachers teaching at different grade levels. The activity was designed to take a single problem situation and develop it in ways appropriate to the different grade levels. At each stage, the teachers are encouraged to discuss teaching approaches required by the students at each grade level and the relationships between the different stages of the development.  相似文献   
57.
International Review of Education - Accelerated learning programmes (ALPs) provide a fast-track second-chance opportunity to complete formal education, enabling disadvantaged children and youth to...  相似文献   
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Currently employed markers for the detection of acute coronary syndrome are Troponin T, CK (Creatine Kinase) and CKMB activity. CKMB activity measured by immunoinhibition method can give falsely elevated results due to the presence of atypical CK and CKBB and at times lead to the mis-diagnosis of acute coronary syndrome. Hence, CKMB mass (CKMB) measured by electrochemiluminence sandwich principle was employed. In this cross-sectional study 183 samples of 61 patients were analyzed within 6 h of diagnosis of acute coronary syndrome and followed up to 72 h. The correlation coefficient between CKMB activity and CKMBM at 4–6 h was 0.744, while at 12–24 h it was 0.909 and at 48–72 h it was 0.337. Thus there was good association between the two methods at 12–24 h but, statistically for method comparison studies and for replacing one method by another, the two methods need to be in agreement with one another. In this study the two methods are not in agreement with one another and thus analytically not replaceable. Another finding was obtained that CKMBM reached cut off levels prior to CKMB enzyme activity and hence, CKMBM is clinically better than CKMB activity to detect reinfarction.  相似文献   
60.
Context Two Biosystems analysers are used in our laboratory, a fully automated A25 and a semi-automated BTS-350. Internal quality control is done for both but external quality control only for A25. As BTS-350 is used for backup, it is important that the results of both analysers are not just comparable but also within predefined limits of systematic, random and total error (TE). Aim To evaluate the imprecision, bias and TE of the two Biosystem analysers. Materials and Methods Biosystems level-1 quality control sera lot number 70A was run in duplicate for 32 days on both the analysers. Between day imprecision (measured by the coefficient of variation), bias and TE were calculated for ten analytes and were checked to see whether they are within the acceptable minimum limits, desirable limits and optimum limits of allowable error based on specifications on Westgard’s website updated in 2014. Results On both the analysers, all the analytes except alkaline phosphatase were within the acceptable minimum limits of TE and most analytes were within the desirable limits of TE. Only TG on A25 was within the optimum limit of TE. Conclusion The two Biosystem analysers performed comparably with errors within acceptable limits for most analytes. BTS-350 was found to be a suitable and ready backup analyser for A25.  相似文献   
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