How Teacher Support Affects Migrant Children’s Learning Satisfaction

Teacher support significantly affects student learning and directly relates to their academic development. Learning satisfaction is the subjective perception and evaluation of learning quality on the part of the student, which represents, to certain extent, the quality of education. Based on data from a questionnaire survey of 1251 migrant children in grades three throughout six, this study analyzed how teacher support impacted the learning satisfaction of migrant children. Research findings indicated that teacher support had a significantly positive effect on migrant children’s learning satisfaction; and that teacher support indirectly and positively affects their learning satisfaction through the separate mediating effect of their learning engagement as well as via the chain mediating effects of their academic adjustment and learning engagement

Sensitivity of the global carbonate weathering carbon-sink flux to climate and land-use changes

The response of carbonate weathering carbon-sink flux (CCSF) to its environmental drivers is still not well understood on the global scale. This hinders understanding of the terrestrial carbon cycle. Here, we show that there is likely to be a widespread and consistent increase in the global CCSF (ranging from + 9.8% (RCP4.5) to + 17.1% (RCP8.5)) over the period 1950–2100. In the coming years the increasing temperature might be expected to have a negative impact on carbonate weathering. However, the increasing rainfall and anticipated land-use changes will counteract this, leading to a greater CCSF. This finding has been obtained by using long-term historical (1950–2005) and modeled future (2006–2100) data for two scenarios (RCP4.5 and RCP8.5) for climate and land-use change in our CCSF equilibrium model. This study stresses the potential role that carbonate weathering may play in the evolution of the global carbon cycle over this century

The Impact of Achievement Goal Orientations on Learning Satisfaction of Secondary School Students: The Chain Mediating Effect of Academic Self-efficacy and Learning Engagement

Learning satisfaction is the feeling or attitude of learners towards learning activity participation, reflecting the degree of their fondness for learning activities as well as the extent to which their needs for learning are met or learning goals are achieved. Achievement goal orientations refer to students’ general tendencies for approaching, engaging in, and evaluating their academic progress and performance in achievement contexts. Achievement goal orientations address the reasons and purposes of individuals’ attempt to accomplish certain achievement outcomes. Academic self-efficacy has significant influences on students’ persistence, perseverance, and emotion-regulation in the learning process, and is a key factor in heightening their learning motivation and improving their academic performance

Karst Aquifers as Atmospheric Carbon Sinks: An Evolving Global Network of Research Sites

Karst flow systems formed in carbonate rocks have been recognized as a sink for atmospheric carbon that originates as gaseous carbon dioxide and ends up as dissolved aqueous carbon, primarily as bicarbonate. While measurements of the magnitude of the sink associated with carbonate rock dissolution have assumed that half of the dissolved inorganic carbon leaving a given catchment comes from the mineral and half from the atmosphere, consideration of the kinetics of carbonate mineral dissolution in acid solutions suggests that the ratio is enriched in mineral-source carbon to an extent that depends on the geochemical environment of mineral/fluid contact. After developing a methodology for precise field measurement of both the magnitude of this sink as well as the partitioning of inorganic carbon sources in south central Kentucky, in 2001 we initiated a long-term project to improve understanding and estimates of the sink with a global monitoring network. The first two new stations and methodology are described herein. In addition to the existing Kentucky sites, we are now making high-resolution measurements in the Mineral King Valley, an alpine marble catchment within California\u27s Sierra Nevada, at an elevation from 2,400 to 3,650 m, and at Spring 31 of the Karst Dynamics Laboratory\u27s experimental research site near Guilin, China. This humid-subtropical site drains an area of peak cluster tower karst at an elevation from 150 to 450 m, and is considerably warmer and wetter than south central Kentucky. For relatively remote sites, the importance of data logging equipment redundancy is becoming clear

Nonlinear vibrations of beams with spring and damping delayed feedback control

The primary, subharmonic, and superharmonic resonances of an Euler–Bernoulli beam subjected to harmonic excitations are studied with damping and spring delayed-feedback controllers. By method of multiple scales, the non-linear governing partial differential equation is transformed into linear differential equations directly. Effects of the feedback gains and time-delays on the steady state responses are investigated. The velocity and displacement delayed-feedback controllers are employed to suppress the primary and superharmonic resonances of the forced nonlinear oscillator. The stable vibration regions of the feedback gains and time-delays are worked out based on stablility conditions of the resonances. It is found that proper selection of feedback gains and time-delays can enhance the control performance of beam’s nonlinear vibration. Position of the bifurcation point can be changed or the bifurcation can be eliminated

Spatial and temporal hydrochemical variations of the spring-fed travertine-depositing stream in the Huanglong Ravine, Sichuan, SW China

Automatic hydrochemical logging and in situ titration com­bined withlaboratory analysis were used to understand the spatial and temporal hydrochemical variations of the spring-fed, travertine-depositing stream in celebrated Huanglong Ravine, Sichuan, SW China. This is essential for protection of the Huanglong World Natural Heritage travertine land­scape. It was found that the deposition of travertine was due to very strong CO2 degassing from the water, leading to de­crease in pCO2 and specific conductivity (SpC), and increase in pH and SIc downstream from the Spring. However, regular downstream hydrochemical evolution was interrupted by di­lution withsnow-melt water and by renewed CO2 from some downstream springs. The chemistry of Huanglong Spring itself was stable at a diurnal scale thoughit was altered by the great Wenchuan earthquake of May 12 2008. However, in spring-fed pools downstream, pCO2 and SpC were lower, and pH and SIc were higher in daytime than at night, whichindicates that the deposition of travertine was faster during the daylight hours. This was due to the combined effects of higher water tempera­tures and higher aquatic algae photosynthesis. In addition, it was found that the phosphate concentration in the stream in­creased remarkably downstream in the tourist midseason, in­dicating water pollution by tourism activities. The increase of phosphate (an inhibitor of calcite precipitation) may be one of the reasons for the decrease in travertine deposition rates and accelerated propagation of discoloration by diatoms during the past decades, whichneeds to be given more comprehensive study and tackled in future for the protection of these world famous travertine deposits

School bullying among migrant children in China: A cross-sectional study

BackgroundBullying is a serious public health concern affecting the physical and mental health of children. Migrant children are at higher risk of developing health problems. We conducted this study to investigate the prevalence of school bullying and its possible influencing factors of migrant children.MethodsA cross-sectional study was carried out in Hunan Province, China from April to July 2018. Multi-stage cluster sampling was adopted to achieve a representative sample covering both urban and rural areas. Migrant children are defined as those who migrate with one or both parents to other places and who do not have a hukou in their city of residence. The Chinese version of Olweus Bully/Victim Questionnaire was applied to measure children’s involvement in school bullying.ResultsA total of 7,607 students were surveyed, including 995 migrant children and 6,612 non-migrant children. The prevalence of school bullying was significantly higher in migrant children than in non-migrant children (χ2 = 22.740; p < 0.001). Binary regression analysis showed that male, middle school identity, more times of playing violent games, more social friends owning and being beaten by parents or caregivers may increase the risk of involvement of school bullying in migrant children.ConclusionMigrant children showed a higher prevalence of school bullying than non-migrant children. Gender, grade, frequency of playing violent games, number of social friends and being beaten by parents or caregivers were associated with school bullying in migrant children

Acute Effects of Particulate Air Pollution on Ischemic Stroke and Hemorrhagic Stroke Mortality

Background and Purpose: A large body of literature reported the association of particulate matter (PM) with stroke in high-income countries. Few studies have examined the association between PM and stroke in middle- and low-income countries and considered the types of stroke. In this study, we examined the short-term effects of particulate matter <2.5 μm in diameter (PM2.5) and particulate matter <10 μm in diameter (PM10) on ischemic stroke mortality and hemorrhagic stroke mortality in Beijing, China.Methods: We used an ecological study design and quasi-Poisson generalized additive models to evaluate the association of PM2.5 and PM10 and cerebrovascular diseases mortality, as well as ischemic- and hemorrhagic stroke mortality. In the model, we controlled long-term and season trends, temperature, and relative humidity, the day of the week and air pollution. For cerebrovascular diseases mortality, we examined the effects stratified by sex and age with different lag days.Results: A total of 48,122 deaths for cerebrovascular disease (32,799 deaths for ischemic stroke and 13,051 deaths for hemorrhagic stroke) were included in the study. PM2.5 was associated with stroke mortality. The 10 μg/m3 increase of PM2.5 was associated with the increase of mortality, 0.27% (95% CI, 0.12–0.43%) for cerebrovascular diseases, 0.23% (95% CI, 0.04–0.42%) for ischemic stroke and 0.37% (95% CI, 0.07–0.67%) for hemorrhagic stroke -. The associations between PM10 and mortality were also detected for cerebrovascular diseases and ischemic stroke, but not in hemorrhagic stroke. The stratified analysis suggested age and gender did not modify the effects of PM on mortality significantly.Conclusions: Our study suggested that short-term exposure to ambient PM was associated with the risk of stroke mortality