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41.
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
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Bilal Ashraf Akansha Singh Germaine Uwimpuhwe Steven Higgins Adetayo Kasim 《British Educational Research Journal》2021,47(6):1675-1699
Meta-analysis is the synthesis of findings from research projects, which enables an estimate of the average or pooled effect across various studies. This study presents findings from the intention to treat analysis for a series of educational evaluations in England using a two-stage meta-analysis with standardised outcome data and individual participant data meta-analyses. The research estimates the overall impact of educational trials on pupils eligible for Free School Meals (FSM) and the attainment gap in literacy and mathematics performance between FSM and non-FSM pupils based on analysis of 88 trials and data from over half a million pupils. For the meta-analyses, frequentist and Bayesian multilevel models were used to estimate the individual and pooled effect size across categories of explanatory variables such as age groups (key stages in England) and aspects of the type of interventions (one-to-one, small group, whole class). Results indicated that the overall impact of interventions on the literacy outcomes of FSM pupils was positive, with a pooled effect size of 0.06 (0.03, 0.08). However, for mathematics, no overall effect on FSM pupils was observed. Analysis of the attainment gap indicated that literacy outcomes for FSM pupils were improved by interventions marginally more than for non-FSM pupils (pooled attainment gap 0.01 (−0.01, 0.04)). The risk of bias assessment showed that estimates were consistent across different methodological approaches. Overall, evidence from this study can be used to identify, test and scale educational interventions in schools to improve educational outcomes for disadvantaged pupils. 相似文献
45.
Given the significant negative impacts of peer victimization on youth development, studies have sought to understand what buffers against these consequences. To that end, the present study examined whether teacher attachment and perceptions of school safety moderated the associations between different forms of victimization and school absences over the course of an academic year among a sample of 272 high school students. Findings indicated that teacher attachment moderated the associations between relational and cyber victimization and absences, while perceived school safety moderated associations between relational victimization and absences. However, findings pertaining to cyber victimization were not as anticipated. Implications for prevention and intervention efforts in high schools are discussed. 相似文献
46.
Chitra Upadhyaya Sandhya Mishra P. P. Singh Praveen Sharma 《Indian journal of clinical biochemistry : IJCB》2005,20(1):30-34
Serum antioxidant status and peroxidative stress was estimated in 30 pregnant women, their newborn infants and 25 non-pregnant
women. Serum Ascorbic acid, α-tocopherol, retinol & β-carotene levels were found to be significantly reduced and peroxidative
stress was significantly higher in mothers as compared to matched non-pregnant women. Newborn had significantly higher levels
of ascorbic acid as compared to their mother but had significantly lower levels of lipid soluble vitamins. The peroxidative
stress in newborn was found to be significantly less as compared to their mothers. A positive correlation of ascorbic acid
and α-tocopherol levels between mother and newborn reflects that their status in mother does influence the newborn status. 相似文献
47.
Shubham Goel Ravinder Kumar Munish Kumar Vikram Chopra 《Information processing & management》2019,56(3):1053-1066
In the whole world, the internet is exercised by millions of people every day for information retrieval. Even for a small to smaller task like fixing a fan, to cook food or even to iron clothes persons opt to search the web. To fulfill the information needs of people, there are billions of web pages, each having a different degree of relevance to the topic of interest (TOI), scattered throughout the web but this huge size makes manual information retrieval impossible. The page ranking algorithm is an integral part of search engines as it arranges web pages associated with a queried TOI in order of their relevance level. It, therefore, plays an important role in regulating the search quality and user experience for information retrieval. PageRank, HITS, and SALSA are well-known page ranking algorithm based on link structure analysis of a seed set, but ranking given by them has not yet been efficient. In this paper, we propose a variant of SALSA to give sNorm(p) for the efficient ranking of web pages. Our approach relies on a p-Norm from Vector Norm family in a novel way for the ranking of web pages as Vector Norms can reduce the impact of low authority weight in hub weight calculation in an efficient way. Our study, then compares the rankings given by PageRank, HITS, SALSA, and sNorm(p) to the same pages in the same query. The effectiveness of the proposed approach over state of the art methods has been shown using performance measurement technique, Mean Reciprocal Rank (MRR), Precision, Mean Average Precision (MAP), Discounted Cumulative Gain (DCG) and Normalized DCG (NDCG). The experimentation is performed on a dataset acquired after pre-processing of the results collected from initial few pages retrieved for a query by the Google search engine. Based on the type and amount of in-hand domain expertise 30 queries are designed. The extensive evaluation and result analysis are performed using MRR, [email protected], MAP, DCG, and NDCG as the performance measuring statistical metrics. Furthermore, results are statistically verified using a significance test. Findings show that our approach outperforms state of the art methods by attaining 0.8666 as MRR value, 0.7957 as MAP value. Thus contributing to the improvement in the ranking of web pages more efficiently as compared to its counterparts. 相似文献
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Anurag Srivastava L. D. Joshi S. P. Singh 《Indian journal of clinical biochemistry : IJCB》1989,4(1):50-57
Normal and alloxan induced diabetic guinea pigs were kept on whole seed diet of green gram for 4 weeks. Serum total lipids
were found to be significantly decreased in both normal and diabetic guinea pigs (P <0.001)—Both free and esterified fractions
of cholesterol were found to be lowered significantly in diabetic animals (P<0.05; <0.01, respectively), whereas only esterified
fraction was reduced significantly in case of normals (P<0.05). Significant lowering of triglyceride levels (P<0.01) was also
noticed in both normal as well as diabetic guinea pigs while phospholipids remained almost unaffected. Green gram feeding
decreased the total cholesterol / phospholipid ratio from 0.630 to 0.625 in normal and from 1.039 to 0.850 in diabetic guinea
pigs indicating its antiatherogenic nature. 相似文献
50.
The high mobility group (HMG) proteins I and Y are well characterised non-histone chromosomal proteins which bind to A-T rich
regions of DNA and regulate gene expression and/or DNA replication. A correlation has been demonstrated between the increased
expression of HMG-Y proteins and malignancy. However, it is not known whether the expression of HMGs particularly, the Y group,
is a function of proliferation rate. In the present study, we have used normal tissues of calf testes, thymus and liver. The
results show distinctly high expression of HMG-Y proteins in testes than in thymus and the expression was practically undetectable
in liver. The results suggest that even in normal tissues there is a direct correlation between the proliferation rate and
the expression of the HMG-Y proteins, which can partly explain its increased expression in cancer. 相似文献