52 research outputs found

    The Influence of Technology Use on Learning Skills Among Generation Z:A Gender and Cross-country Analysis

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    This inquiry flags the shortage of evidence on the distinctive effect of technology use on defined learning skills. To tackle this inertia, it identifies (1) video gaming, (2) internet searching and (3) smartphone usage as ubiquitous forms of technology. Then, it characterises (1) abstract conceptualisation, (2) concrete experience and (3) reflective observation and active experimentation as dominant learning skills. Investigating a Nigeria and UK sample of 240 generation Z students, the associations are examined alongside the effects of gender and country. Based on a structural equation model, the analysis showed that although alternate uses of technology have mostly significant influences, their impact is largely negative with only internet searching having a positive effect on learning. The findings are explained through a cognitive load lens and insights are offered to learning providers to temper the appetite for technology use in instructional designs with thought and caution

    Burden of disease and circulating serotypes of rotavirus infection in sub-Saharan Africa: systematic review and meta-analysis.

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    Two new rotavirus vaccines have recently been licensed in many countries. However, their efficacy has only been shown against certain serotypes commonly circulating in Europe, North America, and Latin America, but thought to be globally important. To assess the potential impact of these vaccines in sub-Saharan Africa, where rotavirus mortality is high, knowledge of prevalent types is essential because an effective rotavirus vaccine is needed to protect against prevailing serotypes in the community. We did two systematic reviews and two meta-analyses of the most recent published data on the burden of rotavirus disease in children aged under 5 years and rotavirus serotypes circulating in countries in sub-Saharan Africa. Eligible studies were selected from PubMed/Medline, Cochrane Library, EmBase, LILACS, Academic Search Premier, Biological Abstracts, ISI Web of Science, and the African Index Medicus. Depending on the heterogeneity, DerSimonian-Laird random-effects or fixed-effects models were used for meta-analyses. Geographical variability in rotavirus burden within countries in sub-Saharan Africa is substantial, and most countries lack information on rotavirus epidemiology. We estimated that annual mortality for this region was 243.3 (95% CI 187.6-301.7) deaths per 100,000 under 5 years (ie, a total of 300,000 children die of rotavirus infection in this region each year). The most common G type detected was G1 (34.9%), followed by G2 (9.1%), and G3 (8.6%). The most common P types detected were P[8] (35.5%) and P[6] (27.5%). Accurate information should be collected from surveillance based on standardised methods in these countries to obtain comparable data on the burden of disease and the circulating strains to assess the potential impact of vaccine introduction

    Inhibitory effects of swietenia mahagoni seeds extract on A-glucosidase and A-amylase

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    This study analyzed the inhibition activity of Swietenia mahagoni seeds extract on α-glucosidase and α-amylase enzymes inhibition assays. Swietenia mahagoni seeds were extracted by using supercritical carbon dioxide (SC-CO2) extraction at pressures of 20-30 MPa and temperatures of 40-60°C. The oil yields obtained were analyzed with α- glucosidase and α- amylase enzymes inhibition assays. All data obtained were expressed as mean ± standard deviation for triplicate experiments. One way analysis was used for statistical significance by using statistica software version 7.0 (StartSoft, EUA) and IC50 (extract concentration causing 50% enzyme inhibitory) was determined by using GraphPad Prism 6.0 software. Swietenia mahagoni seeds extract have a strong inhibition of α-glucosidase enzyme activity (98.4% ± 0.2) but a moderate inhibition of α- amylase enzyme activity (34.9% ± 1.2). These findings implied that Swietenia mahagoni seeds extract could be an effective natural antidiabetic agent

    Emergence of unusual human rotavirus strains in Salento, Italy, during 2006–2007

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    <p>Abstract</p> <p>Background</p> <p>In recent years, rotavirus genotyping by RT-PCR has provided valuable information about the diversity of rotaviruses (RV) circulating throughout the world.</p> <p>The purpose of the present study was to monitor the prevalence of the different G and P genotypes of rotaviruses circulating in Salento and detect any uncommon or novel types.</p> <p>Methods</p> <p>During the period from January 2006 to December 2007, a total of 243 rotavirus positive stool samples were collected from children with diarrhoea admitted to four Hospitals in the province of Lecce (Copertino, Galatina, Gallipoli and Tricase).</p> <p>All the specimens were tested for RV by real time PCR and genotyped for VP7 (G-type) and VP4 (P-type) gene by reverse transcription (RT) and multiplex PCR using different type specific primers.</p> <p>Results</p> <p>In course of this study we identified 4 common G&P combinations viz. G2P[8], G1P[8], G2P[4] and G9P[8] amongst 59.8% of the typeable rotavirus positives.</p> <p>Rotavirus G2P[8] was recognized as the most widespread genotype during the sentinel-based survey in Salento.</p> <p>The detection of other novel and unusual strains, such as G2P[10], G4P[10], G8P[4], G9P[11] and G10P[8] is noteworthy.</p> <p>Furthermore, a significant number of mixed infections were observed during the survey period but G3P[8] rotaviruses were not detected.</p> <p>Conclusion</p> <p>This study highlights the genetic diversity among rotaviruses isolated from children in Salento and the emergence of some novel strains. Therefore, it is highly essential to continuously monitor for these strains so as to assess the impact of vaccines on RV strains circulating in Salento and understand the effect of strain variation on efficacy of presently available vaccines.</p

    Lipid changes in male Albino rats exposed to graded doses of Lead

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    In order to determine the lipid changes in male albino rats exposed to graded doses of lead as lead acetate for periods of 4, 8 and 12 weeks, a total of 60 male albino rats were divided into four groups as, A, B, C and D. Group A served as the control while groups B, C and D were exposed to 200, 300 and 400 ppm, respectively. At the end of exposure period, blood samples were collected for the determination of lead concentration. Total triglyceride, total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol and phospholipid concentrations were also determined in the plasma. There was a significant (p &lt; 0.05) period and dose dependent increase in blood lead concentrations in treated groups compared to the control group while plasma triglyceride and cholesterol concentrations followed similar patterns of alterations. The high density lipoprotein cholesterol and low density cholesterol concentrations show varying degrees of alterations, with a significant increase in high density cholesterol fractions while a significant decrease in the low density cholesterol fractions. The phospholipid concentration showed a dose-dependent decrease. It can be concluded that exposure to varying concentrations of lead over varying periods of exposures show accumulation of lead in the blood together with varying alterations in some of the lipid parameters of male albino rats

    Analysis of a 4-span continuous plate in one direction using Matlab programming

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    The present study presents a computer approach based on polynomial shape functions application for analysis of continuous plate in one direction using Matlab. A 4-span continuous plate in the x-direction comprises of boundary conditions SSSC, SCSC, SCSC and SCSS single panels’ plate was analyzed. It was assumed that, the external edges were simply supported while the internal edges of each panel were clamped. The bending moments of the clamped edges were calculated for each panel using appropriate boundary conditions which formed the fixed end moments (FEMs). Stiffness method was used based on beam analogy to analyze the continuous plate. Matlab codes were applied to develop a computer program for this analysis. To validate the results of this present study, the values of the moments obtained were compared with those of earlier studies using manual method. The percentage difference for fixed end moments were all 0.00% and that of support moments had the maximum value of 0.016%. Thus, it was concluded that the present study program based on Matlab is adequate and a faster approach for a 4-span continuous plate in one direction analysis. Keywords: Matlab Programming, Continuous Plate, Polynomial Shape Functions, Beam Analogy, Fixed Edge Moment

    2-5A-antisense inhibition of respiratory syncytial virus replication: Effects of oligonucleotidestructure modifications and RNA target site selection

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    To define more fully the conditions for 2-5A-antisense inhibition of respiratory syncytial virus (RSV), relationships between 2-5A antisense oligonucleotide structure and the choice of RNA target sites to inhibition of RSV replication have been explored. The lead 2-5A-antisense chimera for this study was the previously reported NIH8281 that targets the RSV M2 RNA. We have confirmed and extended the earlier study by showing that NIH8281 inhibited RSV strain A2 replication in a variety of antiviral assays, including virus yield reduction assays performed in monkey (EC90=0.02 μM) and human cells (EC90=1 μM). This 2-5A-antisense chimera also inhibited other A strains, B strains and bovine RSV in cytopathic effect inhibition and Neutral Red Assays (EC50 values=0.1–1.6 μM). The 2′-O-methylation modification of NIH8281 to increase affinity for the complementary RNA and provide nuclease resistance, the introduction of phosphothioate groups in the antisense backbone to enhance resistance to exo- and endonucleases, and the addition of cholesterol to the 3′-terminus of the antisense oligonucleotide to increase cellular uptake, all resulted in loss of activity. Of the antisense chimeras targeting other RSV mRNAs (NS1, NS2, P, M. G, F, and L), only those complementary to L mRNA were inhibitory. These results suggest that lower abundance mRNAs may be the best targets for 2-5A-antisense; moreover, the active 2-5A antisense chimeras in this study may serve as useful guides for the development of compounds with improved stability, uptake and anti-RSV activity

    Synthesis and nucleic-acid-binding properties of sulfamide- and 3′-N-sulfamate-modified DNA

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    A novel synthetic route for the preparation of sulfamide- and 3'-N-sulfamate-modified dinucleosides has been developed. The synthesis utilises 4-nitrophenyl chlorosulfate to prepare 4-nitrophenyl 3'- or 5'-sulfamates (e.g., 18 and 27), which couple smoothly with the alcohol or amine functionalities of other nucleosides. The conformational properties of the sulfamide- and 3'-N-sulfamate-modified dinucleosides d(TnsnT) and d(TnsoT) were compared with the native dinucleotide d(TpT) using NMR and CD spectroscopy. Whilst both modi cations result in a shift in the conformational equilibrium of the 5'-terminal ribose rings from C2'-endo to a preferred C3'-endo conformation, only the 3'-N-sulfamate-modified dimer exhibits an increased propensity to adopt a base-stacked helical conformation. Incorporation of the sulfamide- and 3'-N-sulfamate modi cations into the DNA sequence d(GCGT(10)GCG) allowed the duplex melting temperature to be determined using UV thermal denaturation experiments. This reveals that the sulfamide modi cation significantly destabilises duplexes with both complementary DNA and RNA. However, the 3'-N-sulfamate modi cation has little effect on duplex stability and even stabilises DNA duplexes at low salt concentration. These results indicate that the 3'-N-sulfamate group is one of the most promising neutral replacements of the phosphodiester group in nucleic acids, that have been developed to date, for therapeutic and other important applications
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