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In this article we derive the distribution, mean and variance of the number of cycles in a randomly selected permutation of the first n integers.  相似文献   
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E-mail-alerting system of online databases is a new trend catching up fast with researchers. Results of auto-run set queries are informed through e-mails as ‘alerts’ to the registered user. Even though e-mail-alerting systems are quite popular amongst Internet users, their inherent advantages remain unexplored in the Indian scenario. An effort to explore all such features available in the ScienceDirect online database has been made in this paper. The process of registration for activating e-mail alerts, customizing a home page, selecting favorite journals, search alerts, journal issue alerts, citation alerts and search history are briefed with screen shot examples. The study emphasizes the fact that librarians and information Science professionals should take lead roles in unveiling all such possible features available in various online databases. They should also make efforts at informing the user community of the utility of such features in a bid to enhance the research output.  相似文献   
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Psoriasis is a chronic inflammatory, proliferative skin disease characterized by pathological skin lesions due to various exogenous and endogenous factors. It is associated with a number of biochemical and immunological disturbances. Recently, it has been suggested that increased reactive oxygen species (ROS) production and compromised function of antioxidant system may be involved in the pathogenesis of this disease. In the present study, 90 psoriasis patients were selected. Disease severity was assessed by psoriasis area severity index score and grouped as mild, moderate and severe (each group consists of 30 subjects) and compared with 30 healthy controls. Serum levels of malondialdehyde, nitric oxide end products and the activities of antioxidant enzymes such as erythrocyte-superoxide dismutase, catalase and total antioxidant status were investigated in these groups/subjects. As compared to controls, we found severitywise significantly increased serum malondialdehyde, nitric oxide end products with decrease in erythrocyte-superoxide dismutase activity, catalase activity and total antioxidant status in patients with psoriasis suggesting worsening of the disease. It seems to be linked with the enhancement of Reactive Oxygen Species production and decreased antioxidant potential in psoriasis.  相似文献   
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International Guidelines have voted for PCR as the Gold Standard in COVID diagnosis. Nasoparyngeal swab is the preferred specimen for PCR. It has a high probability of diagnosing early infection. But the diagnostic sensitivity of nasopharyngeal PCR decreases with increase in lapse between the infection and presentation to hospital. This might lead to dire consequences of labelling these patients as false negative, though such patients have been proved to be potentially infective since viral shedding occurs through other body fluids (stools) for long. COVID infection reveals that the IgM antibodies start to appear as early as 5th day of infection and switches over to IgA within 2–3 days. The aim of the study was to see if COVID antibody testing be coupled with PCR for diagnosis especially in patients presenting late (more than 14 days) of onset of infection? And if the antibodies are giving values, hence can them be reported quantitatively rather than in qualitative fashion? The second objective was to see if the COVID antibody levels be used to monitor the disease severity? And if the antibody levels of SARS CoV 2 be used an indicator to monitor the recovery?  相似文献   
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Student Evaluations of Instruction (SEIs) from about 6,000 sections over 4 years representing over 100,000 students at the college of business at a large public university are analyzed, to study the impact of noninstructional factors on student ratings. Administrative factors like semester, time of day, location, and instructor attributes like gender and rank are studied. The combined impact of all the noninstructional factors studied is statistically significant. Our study has practical implications for administrators who use SEIs to evaluate faculty performance. SEI scores reflect some inherent biases due to noninstructional factors. Appropriate norming procedures can compensate for such biases, ensuring fair evaluations.  相似文献   
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The advent of digital course offerings, the use of social media, the integration of the Khan Academy into curricula, the use of smart phones and tablets, and massive online courses place greater emphasis than ever on effective teaching. While business schools fund faculty development in teaching, too few doctoral programs offer systematic teacher training. We discuss the lack of, and the need for, comprehensive teacher‐training programs. We present the Robinson College of Business model and offer recommendations on how to get started. It is time for PhD programs to certify that their students are capable of teaching upon graduation.  相似文献   
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Tuberculosis remains major health problem in India and developing countries Immunodiagnosis has important role in screening, diagnosis and management of tuberculosis. SEVA TB ES-31 antigen has shown potential in detecting tuberculous IgG antibody in earlier studies from our laboratory. In the present study we have analysedSEVA TB ES-31 antigen specific immunoglobulinsIgM, IgA and IgG in clinically and bacteriologically confirmed pulmonary tuberculosis cases to determine the usefulness of specific immunoglobulin class in the diagnosis of patients attending the hospital. Of the 30 cases of pulmonary tuberculosis 25 (83.3%) were positive for IgG, 19 (63.3%) for IgM and 16 (53.3%) for IgA. On combining IgG and IgM positivity, sensitivity was increased to 93.3%. While combining IgG and IgA positivity, sensitivity increased to 90%. However specificity was decreased to 66.6% and 70% for both of these combinations respectively. It could be envisaged from this study that IgG antibody detection against ES-31 antigen showed acceptable sensitivity (83.3%) and specificity (86.6%) compared to IgM or IgA alone or in combination. When immune responses were analysed according to degree of sputum positivity, IgG response was observed to be predominant in all grades, compared to IgM or IgA antibody. The addition of IgM or IgA as an adjunct test increases the sensitivity but at the cost of specificity. Hence the detection of IgG alone is more useful compared to IgM or IgA assay, in detecting tuberculosis disease cases coming to the hospital.  相似文献   
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提出了一种用于三维电磁场有限元分析的数值技术,即与波阵法配合使用的目标区域定位(TRL)算子.首先对波阵法进行了分析,然后对TRL算子原理进行了详细论述,并讨论了TRL算子在非线性场合应用的可行性,指出其仍能够适用并保持原来的高效率.还介绍了TRL算子在采用矢量磁位函数有限元公式中的实现.最后给出了一个三维静磁场建模的算例,分别采用TRL算子和有限元软件FEMLAB.结果表明:与FEMLAB相比,TRL算子可以节省可观的计算机资源.  相似文献   
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