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The moderating role of socioeconomic status on motivation of adolescents’ foreign language learning strategy use
Previous research has amply established the link between motivation and learning strategy with regards to language learning. However, there have been few investigations into the role of socioeconomic status (SES) in second or foreign language learning. Using questionnaire data on an 8th grade cohort (N ¼ 203, female ¼ 110) from a large urban community in South Korea, we investigated SES as a moderator of the relationship between motivational orientation and language learning strategy use among adolescent students. A series of hierarchical linear models provided empirical evidence that, when drawing only on intrinsic motivation, low-SES adolescents tended to make relatively high use of social strategies. High-SES students, on the other hand, generally showed higher levels of effort, mastery goal orientation, and internal control, and they made greater use of cognitive, metacognitive, compensatory, and social strategies. These findings suggest that an adolescent's SES does affect the relationship between motivation and the use of various language learning strategies; they also suggest the need for greater fostering of low-SES students who are learning foreign languages
Properties of Globular Clusters in Galaxy Clusters: Sensitivity from the Formation and Evolution of Globular Clusters
We investigate the properties of globular clusters in a galaxy cluster, using
the particle tagging method with a semi-analytical approach in a cosmological
context. We assume globular clusters form from dark matter halo mergers and
their metallicity is assigned based on the stellar mass of the host dark matter
halos and the formation redshift of GCs. Dynamical evolution and disruption of
globular clusters are considered using semi-analytical approaches, controlled
by several free parameters. In this paper, we investigate how our results are
changed by the choice of free parameters. We compare our fiducial results with
representative observations, including the mass ratio between the globular
cluster system and its host galaxy, the globular cluster occupancy, the number
fraction of blue globular clusters, and the metallicity gradient with the
globular cluster mass. Because we can know the positions of globular clusters
with time, comparison with additional observations is possible, e.g., the
median radii of the globular cluster system in individual galaxies, the mean
projected density profiles of intracluster globular clusters, and metallicity
and age gradients of globular clusters with a clustercentric radius. We also
find that the specific mass of the globular cluster system in each galaxy is
different with a clustercentric radius.Comment: 21 pages, 14 figures, accepted in Ap
Polysaccharides from the root of Angelica sinensis protect bone marrow and gastrointestinal tissues against the cytotoxicity of cyclophosphamide in mice
Cyclophosphamide (CY) is a cytostatic agent that produces systemic toxicity especially on cells with high proliferative capacity, while polysaccharides from Angelica sinensis (AP) have been shown to increase the turnover of gastrointestinal mucosal and hemopoietic stem cells. It is not known whether AP has an effect on CY-induced cytotoxicity on bone marrow and gastrointestinal tract. In this study, we assessed the protective actions of AP on CY-induced leukopenia and proliferative arrest in the gastroduodenal mucosa in mice. Subcutaneous injection of CY (200 mg/kg) provoked dramatic decrease in white blood cell (WBC) count and number of blood vessels and proliferating cells in both the gastric and duodenal mucosae. Subcutaneous injection of AP significantly promoted the recovery from leukopenia and increased number of blood vessels and proliferating cells in both the gastric and duodenal tissues. Western blotting revealed that CY significantly down-regulated the protein expression of vascular endothelial growth factor (VEGF), c-Myc and ornithine decarboxylase (ODC) in gastric mucosae but had no effect on epidermal growth factor (EGF) expression. AP also reversed the dampening effect of CY on VEGF expression in the gastric mucosa. These data suggest that AP is a cytoprotective agent which can protect against the cytotoxicity of CY on hematopoietic and gastrointestinal tissues when the polysaccharide is co-administered with CY in cancer patients during treatment regimen.published_or_final_versio
Alcohol intake and cardiovascular risk factors:A Mendelian randomisation study
Mendelian randomisation studies from Asia suggest detrimental influences of alcohol on cardiovascular risk factors, but such associations are observed mainly in men. The absence of associations of genetic variants (e.g. rs671 in ALDH2) with such risk factors in women – who drank little in these populations – provides evidence that the observations are not due to genetic pleiotropy. Here, we present a Mendelian randomisation study in a South Korean population (3,365 men and 3,787 women) that 1) provides robust evidence that alcohol consumption adversely affects several cardiovascular disease risk factors, including blood pressure, waist to hip ratio, fasting blood glucose and triglyceride levels. Alcohol also increases HDL cholesterol and lowers LDL cholesterol. Our study also 2) replicates sex differences in associations which suggests pleiotropy does not underlie the associations, 3) provides further evidence that association is not due to pleiotropy by showing null effects in male non-drinkers, and 4) illustrates a way to measure population-level association where alcohol intake is stratified by sex. In conclusion, population-level instrumental variable estimation (utilizing interaction of rs671 in ALDH2 and sex as an instrument) strengthens causal inference regarding the largely adverse influence of alcohol intake on cardiovascular health in an Asian population
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