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1.
Fernandez Frank Baker David P. Fu Yuan-Chih Muñoz Ismael G. Ford Karly Sarita 《Minerva》2021,59(1):79-98
Minerva - Over the course of the 20th century, unprecedented growth in scientific discovery was fueled by broad growth in the number of university-based scientists. During this period the American... 相似文献
2.
Yogesh M. Patel Sanidhya Jain Abhishek Kumar Singh Kedar Khare Sarita Ahlawat Supreet Singh Bahga 《Biomicrofluidics》2020,14(6)
We present design, characterization, and testing of an inexpensive, sheath-flow based microfluidic device for three-dimensional (3D) hydrodynamic focusing of cells in imaging flow cytometry. In contrast to other 3D sheathing devices, our device hydrodynamically focuses the cells in a single-file near the bottom wall of the microchannel that allows imaging cells with high magnification and low working distance objectives, without the need for small device dimensions. The relatively large dimensions of the microchannels enable easy fabrication using less-precise fabrication techniques, and the simplicity of the device design avoids the need for tedious alignment of various layers. We have characterized the performance of the device with 3D numerical simulations and validated these simulations with experiments of hydrodynamic focusing of a fluorescently dyed sample fluid. The simulations show that the width and the height of the 3D focused sample stream can be controlled independently by varying the heights of main and side channels of the device, and the flow rates of sample and sheath fluids. Based on simulations, we also provide useful guidelines for choosing the device dimensions and flow rates for focusing cells of a particular size. Thereafter, we demonstrate the applicability of our device for imaging a large number of RBCs using brightfield microscopy. We also discuss the choice of the region of interest and camera frame rate so as to image each cell individually in our device. The design of our microfluidic device makes it equally applicable for imaging cells of different sizes using various other imaging techniques such as phase-contrast and fluorescence microscopy. 相似文献
3.
Using a random sample of 389 grade 11 science students, the factor structure of the Longeot test (a measure of logical thinking) is investigated and some psychometric properties of the test items are determined. Varimax rotation on six principal component factors resulted in a simple structure. An attempt is made to interpret the obtained orthogonal factors. Implications of the findings on the “unity hypothesis” of the Piagetian construct of logical thinking and, consequently, on grade 11 science education are discussed. 相似文献
4.
Sonya M. Alemán Sarita Gaytán 《International journal of qualitative studies in education》2017,30(2):128-146
Scholars maintain that when race and racism are addressed as factors that continue to shape inequality in the classroom, white students often deny the validity of these claims, while Students of Color tend to feel empowered by them. However, drawing on open-ended interviews, focus group discussions, and survey data, we argue that some Students of Color resist critical race pedagogy and curriculum. Specifically, we identify and analyze how this push back is articulated through three triggers: (1) an entrenchment in majoritarian ideologies; (2) a disavowal of racialized oppression; and (3) a disinclination to scrutinize personal experiences marred by race. These dynamics illustrate what we call ‘resisting decolonization’ – a reluctance to grapple with pedagogies that destabilize dominant ideologies about race and racism in schools and disrupt mainstream ideas regarding ethnic or racial identity. We introduce this concept in an attempt to hone critical race pedagogy to better address the needs of Students of Color who sometimes unknowingly participate in the marginalization of Populations of Color through deficit thinking or through the denial of the continuing significance of race. 相似文献
5.
In this section of Resonance, we invite readers to pose questions likely to be raised in a classroom situation. We may suggest strategies for dealing with 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
6.
Pratibha Dixit Shally Awasthi Nutan Maurya Sarita Agarwal M. Srinivasan 《Indian journal of clinical biochemistry : IJCB》2015,30(1):35-42
Cystic Fibrosis Trans membrane conductance regulator (CFTR) gene is an asthma susceptibility gene. In the present study we investigated the possible association of CFTR gene mutations in Indian asthmatic children as compared to controls. The study included 250 asthmatics and 250 age and sex matched controls. Case to control ratio for sample size was 1:1. Genotyping was performed for 24 CFTR gene mutations by ARMS-PCR and PCR–RFLP method. Among 24 CFTR gene mutations, heterozygous allele of R553X mutation was found in 4 (1.6 %) asthmatic cases and 2 (0.8 %) controls. Value of FVC and FEV1/FVC ratio were significantly lower in heterozygous individuals (p value <0.05). No significant difference was observed in the genotype and allele frequency of R553X mutation (OR = 1.339, 95 % CI = 0.755–2.374, p value = 0.685). Furthermore, all wild type homozygous alleles were observed in remaining 23 CFTR gene mutations. Our data concludes that R553X mutation was not significantly associated in Indian asthmatic children. 相似文献
7.
Lee Irene Grover Shuchi Martin Fred Pillai Sarita Malyn-Smith Joyce 《Journal of Science Education and Technology》2020,29(1):1-8
This article provides an introduction for the special issue of the Journal of Science Education and Technology focused on computational thinking (CT) from a disciplinary perspective. The special issue connects earlier research on what K-12 students can learn and be able to do using CT with the CT skills and habits of mind needed to productively participate in professional CT-integrated STEM fields. In this context, the phrase “disciplinary perspective” simultaneously holds two meanings: it refers to and aims to make connections between established K-12 STEM subject areas (science, technology, engineering, and mathematics) and newer CT-integrated disciplines such as computational sciences. The special issue presents a framework for CT integration and includes articles that illuminate what CT looks like from a disciplinary perspective, the challenges inherent in integrating CT into K-12 STEM education, and new ways of measuring CT aligned more closely with disciplinary practices. The aim of this special issue is to offer research-based and practitioner-grounded insights into recent work in CT integration and provoke new ways of thinking about CT integration from researchers, practitioners, and research-practitioner partnerships.
相似文献8.
Using a sample of 908 eleventh grade science stream male and female students from similar socioeconomic area schools, variance based psychometric properties of three paper-and-pencil tests of logical thinking (Longeot test, Lawson's test TOFR, and Tobin and Capie's test TOLT) are investigated. A sub-sample of 212 students took the three tests in randomly allocated different sequential orders of presentation, while 696 students took only two tests. Alfa coefficients for each test separately and for the three tests combined together, concurrent validity coefficients, measures of item difficulty, item discrimination, item-criterion correlation, and 30-day stability coefficients are calculated. Considering the relative homogeneity of the sample, the reliability coefficients of the tests are judged satisfactory, but concurrent validity coefficients are quite low which implies incongruency in decisions made on the basis of the three tests. Need for estimating various psychometric parameters of alternative tests of logical thinking over different grade populations is emphasized. 相似文献
9.
Sarita Bacciotti Adam Baxter-Jones Adroaldo Gaya José Maia 《Journal of sports sciences》2018,36(7):749-756
This study aimed to identify physique characteristics (anthropometry, somatotype, body proportionality) of Brazilian female artistic gymnasts, and to compare them across competitive levels (sub-elite versus non-elite) within competitive age-categories. Two hundred forty-nine female gymnasts (68 sub-elite; 181 non-elite) from 26 Brazilian gymnastics clubs, aged 9–20 years and split into four age-categories, were sampled. Gymnasts were assessed for 16 anthropometric traits (height, weight, lengths, widths, girths, and skinfolds); somatotype was determined according to Heath-Carter method, body fat was estimated by bioimpedance, and proportionality was computed based on the z-phantom strategy. Non-elite and sub-elite gymnasts had similar values in anthropometric characteristics, however non-elite had higher fat folds in all age-categories (P < 0.01). In general, mesomorphy was the salient somatotype component in all age-categories, and an increase in endomorphy, followed by a decrease in ectomorphy across age was observed. Regarding proportionality, profile similarity was found between sub-elite and non-elite within age-categories. In conclusion results suggest the presence of a typical gymnast’s physical prototype across age and competitive level, which can be useful to coaches during their selection processes in clubs and regional/national teams. 相似文献
10.
Sarita N. Chavan Umesh More Shruti Mulgund Vishal Saxena Alka N. Sontakke 《Indian journal of clinical biochemistry : IJCB》2007,22(2):101-105
Osteoporosis encompasses a wide spectrum of conditions associated with imbalance of osteoclastic and osteoblastic activities.
The increased activity of osteoclasts leads to increased free radical formation and hence lipid peroxidation. Present study
probes into the role of antioxidants as a palliative treatment for osteoporosis. It involved 50 healthy controls and 75 clinically
diagnosed osteoporosis patients. Both the groups underwent baseline assessment of biochemical markers viz. osteoblastic markers:
serum Alkaline phosphatase. Free or ionic calcium and Inorganic phosphorus, osteoclastic markers: serum Tartarate resistant
acid phosphatase and Malondialdehyde and the antioxidant status: serum Superoxide dismutase and Erythrocyte reduced glutathione.
The osteoporotic group was then divided into groups A (Vitamin E-Evinal 400 mg), B (Vitamin C-Celin 500 mg), C (Vitamin E+C-Evinal+Celin)
for antioxidant supplementation for a period of 90 days. The results reveal that there is significant fall in concentration
of serum MDA (p<0.001), TrACP (p<0.01). Improvement in antioxidant status is reflected by significant rise in concentration
of serum SOD (p<0.001) and erythrocyte GSH (p<0.001) after 90 days of antioxidant supplementation in osteoporosis. The findings
indicate that on the whole bone status improved with prolonged antioxidant vitamin supplementation, which can be used as a
palliative treatment for osteoporosis. The efficacy is not affected whether the vitamins are administered singly or conjointly. 相似文献