366 research outputs found

    Prevalence of bullying and victimization among children in early elementary school: Do family and school neighbourhood socioeconomic status matter?

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    Background: Bullying and victimization are widespread phenomena in childhood and can have a serious impact on well-being. Children from families with a low socioeconomic background have an increased risk of this behaviour, but it is unknown whether socioeconomic status (SES) of school neighbourhoods is also related to bullying behaviour. Furthermore, as previous bullying research mainly focused on older children and adolescents, it remains unclear to what extent bullying and victimization affects the lives of younger children. The aim of this study is to examine the prevalence and socioeconomic disparities in bullying behaviour among young elementary school children. Methods. The study was part of a population-based survey in the Netherlands. Teacher reports of bullying behaviour and indicators of SES of families and schools were available for 6379 children aged 5-6 years. Results: One-third of the children were involved in bullying, most of them as bullies (17%) or bully-victims (13%), and less as pure victims (4%). All indicators of low family SES and poor school neighbourhood SES were associated with an increased risk of being a bully or bully-victim. Parental educational level was the only indicator of SES related with victimization. The influence of school neighbourhood SES on bullying attenuated to statistical non-significance once adjusted for family SES. Conclusions: Bullying and victimization are already common problems in early elementary school. Children from socioeconomically disadvantaged families, rather than children visiting schools in disadvantaged neighbourhoods, have a particularly high risk of involvement in bullying. These findings suggest the need of timely bullying preventions and interventions that should have a special focus on children of families with a low socioeconomic background. Future studies are necessary to evaluate the effectiveness of such programs

    Focus Raqqa: inventory of Museum collections and reconstruction of missing tablets

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    The National Museum of Raqqa in Syria has suffered immensely from the ongoing violence since 2011. Much of its valuable collection of movable archaeological heritage (ca. 6000 items) is considered lost. Starting from 500 of the most precious objects of the museum stored in the Raqqa Central Bank and stolen from there in 2013, the pilot project Focus Raqqa created a concrete, workable database to enable identification by Syrian and international police and heritage institutions. The project made a pivotal first step towards potential reconstruction of the Raqqa Museum in the future. The Raqqa museum collection included cuneiform tablets. Some of the tablets were cast before the war to allow detailed study in Europe. Today the tablets have vanished. The pilot project Scanning for Syria safeguarded information from the lost artefacts by making high-resolution three-dimensional scans of the silicone rubber moulds and subsequently physical replicas of the original objects by 3D printing. The short life expectancy (30 years) of the moulds necessitated measures for long-term preservation. The Scanning for Syria team not only succeeded at the preservation and sharing of knowledge in the academic circle. It also told the story of Syrian culture and its people to everyone for raising more voices in the united effort to keep cultural heritage safe in a zone of conflict. Digital Archaeolog

    Trapping of Intermediates with Substrate Analog HBOCaA in the Polymerizations Catalyzer by Class III Polyhydroxybutyrate (PHB) Synthase from Allochromatium Vinosum

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    Polyhydroxybutyrate (PHB) synthases (PhaCs) catalyze the formation of biodegradable PHB polymers that are considered as an ideal alternative to petroleum-based plastics. To provide strong evidence for the preferred mechanistic model involving covalent and noncovalent intermediates, a substrate analog HBOCoA was synthesized chemoenzymatically. Substitution of sulfur in the native substrate HBCoA with an oxygen in HBOCoA enabled detection of (HB)nOCoA (n = 2–6) intermediates when the polymerization was catalyzed by wild-type (wt-)PhaECAv at 5.84 hr−1. This extremely slow rate is due to thermodynamically unfavorable steps that involve formation of enzyme-bound PHB species (thioesters) from corresponding CoA oxoesters. Synthesized standards (HB)nOCoA (n = 2–3) were found to undergo both reacylation and hydrolysis catalyzed by the synthase. Distribution of the hydrolysis products highlights the importance of the penultimate ester group as previously suggested. Importantly, the reaction between primed synthase [3H]-sT-PhaECAv and HBOCoA yielded [3H]-sTet-O-CoA at a rate constant faster than 17.4 s−1, which represents the first example that a substrate analog undergoes PHB chain elongation at a rate close to that of the native substrate (65.0 s−1). Therefore, for the first time with a wt-synthase, strong evidence was obtained to support our favored PHB chain elongation model

    Bidirectional regulation of bone formation by exogenous and osteosarcoma-derived Sema3A

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    Semaphorin 3A (Sema3A), a secreted member of the Semaphorin family, increases osteoblast differentiation, stimulates bone formation and enhances fracture healing. Here, we report a previously unknown role of Sema3A in the regulation of ectopic bone formation and osteolysis related to osteosarcoma. Human recombinant (exogenous) Sema3A promoted the expression of osteoblastic phenotype in a panel of human osteosarcoma cell lines and inhibited the ability of these cells to migrate and enhance osteoclastogenesis in vitro. In vivo, administration of exogenous Sema3A in mice after paratibial inoculation of KHOS cells increased bone volume in non-inoculated and tumour-bearing legs. In contrast, Sema3A overexpression reduced the ability of KHOS cells to cause ectopic bone formation in mice and to increase bone nodule formation by engaging DKK1/β-catenin signalling. Thus, Sema3A is of potential therapeutic efficacy in osteosarcoma. However, inhibition of bone formation associated with continuous exposure to Sema3A may limit its long-term usefulness as therapeutic agent

    Microarray-Based Transcriptomic Analysis of Differences between Long-Term Gregarious and Solitarious Desert Locusts

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    Desert locusts (Schistocerca gregaria) show an extreme form of phenotypic plasticity and can transform between a cryptic solitarious phase and a swarming gregarious phase. The two phases differ extensively in behavior, morphology and physiology but very little is known about the molecular basis of these differences. We used our recently generated Expressed Sequence Tag (EST) database derived from S. gregaria central nervous system (CNS) to design oligonucleotide microarrays and compare the expression of thousands of genes in the CNS of long-term gregarious and solitarious adult desert locusts. This identified 214 differentially expressed genes, of which 40% have been annotated to date. These include genes encoding proteins that are associated with CNS development and modeling, sensory perception, stress response and resistance, and fundamental cellular processes. Our microarray analysis has identified genes whose altered expression may enable locusts of either phase to deal with the different challenges they face. Genes for heat shock proteins and proteins which confer protection from infection were upregulated in gregarious locusts, which may allow them to respond to acute physiological challenges. By contrast the longer-lived solitarious locusts appear to be more strongly protected from the slowly accumulating effects of ageing by an upregulation of genes related to anti-oxidant systems, detoxification and anabolic renewal. Gregarious locusts also had a greater abundance of transcripts for proteins involved in sensory processing and in nervous system development and plasticity. Gregarious locusts live in a more complex sensory environment than solitarious locusts and may require a greater turnover of proteins involved in sensory transduction, and possibly greater neuronal plasticity
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