88 research outputs found

    Review of K Mean and Fuzzy Clustering Algorithm

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    Data mining is the process of discovering patterns in large data sets. It has attracted a lot of attention from various industries and researchers for critical decision making and development. Researchers has proposed a number of algorithms have been proposed in past for clustering of data as data mining techniques. There are multiple techniques of mining relevant information from existing databases. K-Means is most common used algorithm for clustering. Multiple versions of K-Means have been proposed with different improvements. In this paper, we will review few data clustering techniques

    The Impact of University Student Services and Student Life Characteristics on Students’ Perceptions of Online Education

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    Student support services and student life have been an integral part of most institutions of higher education for decades. Academic advising, registration coordination, formal tutoring, and informal study groups are some of the more important venues that support academic success. This research fills in a critical gap in the higher education literature by reporting on how six university student support services and six student life characteristics impacted student perceptions of academic success in the online environment. The findings also document students perceived ability to move to the online platform, satisfaction with the online learning experience, and willingness to take future online courses by surveying business students at a comprehensive, AACSB-accredited business school. The results indicate a positive impact of services offered by the Academic Advising Office, Registrar’s Office, and the Writing Center whereas a lukewarm response to the Tutoring Center and Peer Mentoring support services. Among student life attributes, campus technology solutions were most helpful to students in achieving their academic goals

    The Impact of Technology on Business Student Success During the COVID-19 Pandemic

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    This report documents the technology issues students encountered during the first two years of the COVID- 19 pandemic. Six different aspects of technology in the pedagogic sphere are examined. Through this analysis, we reveal key aspects external to the effort of faculty that impact student perceptions of online education. Poor internet speed is the most common technology issue cited by respondents whereas the lack of personal computer knowledge is the least cited. Tests are run to assess the variation in student perception based upon their satisfaction with online education that showing students facing no technology related issues report being satisfied with online learning. Suggestions are made regarding how to use these findings to enhance online education in the business college and across campus

    Serum Vitamin D, PTH, and Calcium Levels in Patients with and without Early Childhood Caries

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    Purpose: The purpose was to determine differences in serum vitamin D, parathyroid hormone (PTH), and calcium levels between patients with early childhood caries (ECC) and patients without dental decay. Materials and Methods: Serum vitamin D, PTH, and calcium levels were obtained from 30 children without dental decay who acted as controls and 60 children with ECC. A questionnaire was filled out by the parent/guardian of each participant consisting of questions regarding medical and dental history, exposure to sources of vitamin D and demographic information. Results: The difference in the vitamin D levels of the participants was most strongly associated with race. African American participants demonstrated lower levels of vitamin D than non-African Americans. After adjusting for race- related differences there was no significant difference in the Vitamin D levels in the ECC cases and the healthy controls. Conclusions: The results of this study suggest that vitamin D levels, at least among non-African Americans, are unrelated to caries development. Future research in this area must control for important confounding factors such as skin pigmentation, season of measurement of serum vitamin D, sun exposure, fluoride exposure, water fluoridation status and tooth brushing in order to allow for vitamin D levels to be better tested against caries experience

    Role of the Placental Vitamin D Receptor in Modulating Feto-Placental Growth in Fetal Growth Restriction and Preeclampsia-Affected Pregnancies

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    Fetal growth restriction (FGR) is a common pregnancy complication that affects up to 5% of pregnancies worldwide. Recent studies demonstrate that Vitamin D deficiency is implicated in reduced fetal growth, which may be rescued by supplementation of Vitamin D. Despite this, the pathway(s) by which Vitamin D modulate fetal growth remains to be investigated. Our own studies demonstrate that the Vitamin D receptor (VDR) is significantly decreased in placentae from human pregnancies complicated by FGR and contributes to abnormal placental trophoblast apoptosis and differentiation and regulation of cell-cycle genes in vitro. Thus, Vitamin D signaling is important for normal placental function and fetal growth. This review discusses the association of Vitamin D with fetal growth, the function of Vitamin D and its receptor in pregnancy, as well as the functional significance of a placental source of Vitamin D in FGR. Additionally, we propose that for Vitamin D to be clinically effective to prevent and manage FGR, the molecular mechanisms of Vitamin D and its receptor in modulating fetal growth requires further investigation

    Increased Diacylglycerols Characterize Hepatic Lipid Changes in Progression of Human Nonalcoholic Fatty Liver Disease; Comparison to a Murine Model

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    The spectrum of nonalcoholic fatty liver disease (NAFLD) includes steatosis, nonalcoholic steatohepatitis (NASH), and progression to cirrhosis. While differences in liver lipids between disease states have been reported, precise composition of phospholipids and diacylglycerols (DAG) at a lipid species level has not been previously described. The goal of this study was to characterize changes in lipid species through progression of human NAFLD using advanced lipidomic technology and compare this with a murine model of early and advanced NAFLD.Utilizing mass spectrometry lipidomics, over 250 phospholipid and diacylglycerol species (DAGs) were identified in normal and diseased human and murine liver extracts.Significant differences between phospholipid composition of normal and diseased livers were demonstrated, notably among DAG species, consistent with previous reports that DAG transferases are involved in the progression of NAFLD and liver fibrosis. In addition, a novel phospholipid species (ether linked phosphatidylinositol) was identified in human cirrhotic liver extracts.Using parallel lipidomics analysis of murine and human liver tissues it was determined that mice maintained on a high-fat diet provide a reproducible model of NAFLD in regards to specificity of lipid species in the liver. These studies demonstrated that novel lipid species may serve as markers of advanced liver disease and importantly, marked increases in DAG species are a hallmark of NAFLD. Elevated DAGs may contribute to altered triglyceride, phosphatidylcholine (PC), and phosphatidylethanolamine (PE) levels characteristic of the disease and specific DAG species might be important lipid signaling molecules in the progression of NAFLD

    Minimal information for studies of extracellular vesicles 2018 (MISEV2018):a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines

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    The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points

    Evaluating the Effects of SARS-CoV-2 Spike Mutation D614G on Transmissibility and Pathogenicity.

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    Global dispersal and increasing frequency of the SARS-CoV-2 spike protein variant D614G are suggestive of a selective advantage but may also be due to a random founder effect. We investigate the hypothesis for positive selection of spike D614G in the United Kingdom using more than 25,000 whole genome SARS-CoV-2 sequences. Despite the availability of a large dataset, well represented by both spike 614 variants, not all approaches showed a conclusive signal of positive selection. Population genetic analysis indicates that 614G increases in frequency relative to 614D in a manner consistent with a selective advantage. We do not find any indication that patients infected with the spike 614G variant have higher COVID-19 mortality or clinical severity, but 614G is associated with higher viral load and younger age of patients. Significant differences in growth and size of 614G phylogenetic clusters indicate a need for continued study of this variant

    Effective control of SARS-CoV-2 transmission between healthcare workers during a period of diminished community prevalence of COVID-19

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    Funder: Addenbrooke's Charitable Trust, Cambridge University Hospitals; FundRef: http://dx.doi.org/10.13039/501100002927Funder: National Institute for Health Research; FundRef: http://dx.doi.org/10.13039/501100000272Previously, we showed that 3% (31/1032)of asymptomatic healthcare workers (HCWs) from a large teaching hospital in Cambridge, UK, tested positive for SARS-CoV-2 in April 2020. About 15% (26/169) HCWs with symptoms of coronavirus disease 2019 (COVID-19) also tested positive for SARS-CoV-2 (Rivett et al., 2020). Here, we show that the proportion of both asymptomatic and symptomatic HCWs testing positive for SARS-CoV-2 rapidly declined to near-zero between 25th April and 24th May 2020, corresponding to a decline in patient admissions with COVID-19 during the ongoing UK ‘lockdown’. These data demonstrate how infection prevention and control measures including staff testing may help prevent hospitals from becoming independent ‘hubs’ of SARS-CoV-2 transmission, and illustrate how, with appropriate precautions, organizations in other sectors may be able to resume on-site work safely
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