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1.
Classroom     
In this section of Resonance, we invite readers to pose questions likely to be raised in a classroom situation. Wemay suggest strategies for dealingwith them, or invite responses, or both. “Classroom” is equally a forum for raising broader issues and sharing personal experiences and viewpoints on matters related to teaching and learning science.  相似文献   
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The present study evaluated the plausible role of circulating biomarkers in immune pathogenesis of chronic hepatitis considered a priority in clinical hepatology. Total viral load of chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) patients was quantified and correlation studies were performed with circulating levels of Th1/Th2 cytokines; C reactive protein and circulating nucleosomes; glutathione reductase (GR) and superoxide dismutase. To our knowledge, the study is first among its kind that validates strong positive correlation of viral load with IL-4, IL-6, GR in HBV and IL-6, IL-10, GR in HCV infections. Although, multi-centric studies including large cohorts are required for translating our findings to clinical practice, however, role of these biomarkers with potential diagnostic or prognostic significance might be helpful in clinical assessment of high-risk individuals, thereby, designing interventional strategies, towards development of personalized medicare. The results of our study also offer valuable insights of immune signaling mediators engaged in development of hepatocellular carcinoma.  相似文献   
4.
ABSTRACT

This study compared five different methods for analyzing accelerometer-measured physical activity (PA) in older adults and assessed the relationship between changes in PA and changes in physical function and depressive symptoms for each method. Older adult females (N = 144, Mage = 83.3 ± 6.4yrs) wore hip accelerometers for six days and completed measures of physical function and depressive symptoms at baseline and six months. Accelerometry data were processed by five methods to estimate PA: 1041 vertical axis cut-point, 15-second vector magnitude (VM) cut-point, 1-second VM algorithm (Activity Index (AI)), machine learned walking algorithm, and individualized cut-point derived from a 400-meter walk. Generalized estimating equations compared PA minutes across methods and showed significant differences between some methods but not others; methods estimated 6-month changes in PA ranging from 4 minutes to over 20 minutes. Linear mixed models for each method tested associations between changes in PA and health. All methods, except the individualized cut-point, had a significant relationship between change in PA and improved physical function and depressive symptoms. This study is among the first to compare accelerometry processing methods and their relationship to health. It is important to recognize the differences in PA estimates and relationship to health outcomes based on data processing method.

Abbreviation: Machine Learning (ML); Short Physical Performance Battery (SPPB); Center of Epidemiologic Studies Depression Scale (CES-D); Physical Activity (PA); Activity Index (AI); Activities of Daily Living (ADL)  相似文献   
5.
Depletion of the Earth’s ozone layer is one of the major environmental concerns for the new millennium having serious implications on human health, agriculture and climate. In the past decades, research by the international scientific community has been directed towards understanding the impact of human interference on the Earth’s atmosphere. The importance of ozone radiation absorption in the atmosphere and the general kinetics of the stratospheric ozone depletion mechanisms have motivated many theoretical and experimental studies on various chemical species. The distribution of ozone and other trace gases in the atmosphere is governed by the complex interaction of dynamical, chemical and radiative processes. This article concentrates on the basic concepts underlying the problems that may be faced by humankind due to reduction in the ozone layer in coming decades, and the ways in which the scientific community can contribute to predicting and remediating these effects through design of international treaties, regulations and amendments.  相似文献   
6.
The purpose of this study was to create a substantial body of knowledge about the factors that influence the success of electronic journals, and to share this knowledge with that in the fields of astronomy and astrophysics in order to help facilitate change.

Structured questionnaires for users (Academic Members, Post-Doctoral Fellows and Research Scholars) containing 40 different questions, many of which were further subdivided and framed in order to get information on various aspects of the usage of electronic journals. The purpose was to identify the basic minimum infrastructure necessary to provide users access to electronic journals and to facilitate easy response in all major A&A organizations in India.

The increasing use of the electronic information-seeking environment has produced changes in the practice of science. Significant research has been conducted already on the impact of new information and communication technologies on scholarly work.

This study was limited to astronomy and astrophysics libraries and information centres in India.

This paper identifies the information needs of the users. Each community and discipline has its own specific legacy of journal structure, reading, publishing, and researching practices, and it will take trial and error to establish which kinds of e-journals are the most effective and useful.

Case study.  相似文献   
7.
Immune dysregulation is a key feature of the coronavirus disease-2019 (COVID-19). However, disparities in responses across ethnic groups are underappreciated. This study aimed to determine the relationship between chemokines and cytokines and the severity of COVID-19. Multiplex magnetic bead-based Luminex-100 was used to assess chemokine and cytokine levels in COVID-19 patients at admission (day-1) and after 4 days. The mean age of the patients recruited was 54.3 years, with 19 (63.3%) males. COVID-19 patients had significantly lower lymphocyte, monocyte, hemoglobin and eosinophil levels than controls (p < 0.05). COVID-19 patients showed significantly higher neutrophil levels than controls (p < 0.05). The baseline levels of IL-2, IL-6, IL-8, IL-10, and IFN-α/γ significantly increased in COVID-19 patients (p < 0.05). Chemokine levels (IP-10, MCP-1, MIG, and CCL-5) were significantly in COVID-19 patients. IL-8, IP-10, and MIG levels were significantly higher in the patients with severe COVID-19 (p < 0.05). Individuals with mild COVID-19 showed significantly higher levels of INF-α, IL-2, IL-6, and IL-8, whereas IL-10 levels were significantly lower (p < 0.05). TNF-levels decreased significantly in individuals with severe COVID-19, whereas IL-6, IL-8, and MIG levels increased (p < 0.05). After 4 days, INFα-, IL-2, IL-6, IL-8, IP-10, and MIG levels were significantly higher in patients with mild disease, whereas IL-6, MIG, and TNF-αlevels were significantly higher in patients with severe disease (p < 0.05). Thus, we conclude that COVID-19 is characterized by INF-α/γ, IL-6, IL-10, IP-10, MCP-1, MIG, and CCL5 dysregulation. IL-8, MIG, and IP-10 levels distinguish between moderate and severe COVID-19. Changes in INF-α, IL-2, IL-6, IL-8, IP-10, and MIG levels can be used to monitor disease progression.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12291-022-01108-x.  相似文献   
8.
Malondialdehyde (MDA) is widely used as oxidative stress biomarker in biomedical research. Plasma is stored in deep freezers generally till analysis. Effect of such storage on MDA values, which may be variable and prolong, was incidentally observed in the ongoing study which is to estimate oxidative stress with oral iron. Plasma from blood samples of pregnant women (20–30 years age) in third trimester of singleton pregnancy (n = 139), consuming oral iron tablets was stored at −20 °C with intention of MDA estimation, as soon as possible. However logistic problems led this storage for prolonged and variable period (1–708 days). When values of MDA estimated using “Ohkawa” 79 method and readings were plotted against time to check the temporal effect, it showed a hyperbolic curve. Standard deviation (SD) was lowest when samples were tested within 3 weeks time. The samples analyzed within 3 weeks had mean ± SD value of 31.59 ± 26.11 μmol/L, while 123.7 ± 93.97 and 366.5 ± 189.8 μmol/L for samples stored for 1–3 and 4 months to 1 year respectively. Mean ± SD were 539.9 ± 196.8 in the samples store for more than a year. Rate of change in values was also lowest (0.0433 μmol/L/day) in the samples tested within first 3 weeks, which rose to 1.2 μmol/L/day during 3 month’s storage. This rate peaked at storage of 120 days (1.87 μmol/L/day) and fell to 0.502 μmol/L/day in the second year of storage. It is concluded that at −20 °C, only 3 weeks of storage time should be considered valid for fairly acceptable stability in MDA values.  相似文献   
9.
The present study has been conducted in 80 cases, out of which 28 were of strangulated and 52 of non-strangulated intestinal obstruction. It has been observed that serum lactate dehydrogenase of more than 300 I. U./litre in first 24 hours to 72 hours is highly suggestive of strangulated intestinal obstruction.  相似文献   
10.
This article describes a challenging problem concerning a neutron under gravity that was posed as a theoretical problem in the 36th International Physics Olympiad held in Salamanca, Spain from July 3–12, 2005. The Olympiad marked India’s eighth foray into this exciting event where seventyfive nations participated. Our performance was a success and all five student members of the team secured medals which included two gold, two silver and one bronze medals.  相似文献   
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