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21.
Abstract

This study focused on academic and social correlates of collaborator preferences of African American and White sixth-graders in mathematics classrooms in fall and spring. Students’ appraisals of emotional risk were examined as a moderator. Nomination procedures identified collaborator preferences, group affiliations, and social centrality; students self-reported engagement and emotional risk; school records provided achievement scores. Results indicated students preferred group affiliates, but not exclusively, as collaborators. Students with greater centrality, achievement, and engagement received more nominations. In the fall, high achievers received more nominations when appraisals of risk were high; whereas, engaged students whose appraisals of risk were low received more nominations. Results are interpreted in relation to coordinating social and academic factors in peer collaboration.  相似文献   
22.
The complex environmental challenges humanity faces require citizens who are scientifically and environmentally literate. Many environmental education programs are situated in the field where students are immersed in their learning. These field-based activities are engaging but may lack opportunities for students to develop critical thinking and reasoning skills necessary to be environmentally literate. We suggest a socio-scientific issue (SSI) based teaching approach can increase epistemic engagement and lead to student gains in scientific and environmental literacy. This study describes how we modified an existing field-based ecology course, framing the learning around a local environmental socio-scientific issue. We used a convergent parallel mixed-methods approach to examine the changes in socio-scientific reasoning (SSR) over time for high school students in this course as a measure of scientific and environmental literacy. Results indicate that a focused SSI field-based environmental education curriculum can support development of socio-scientific reasoning and environmental literacy competencies among high school students.  相似文献   
23.
为考察学校情境下的环境知觉、自我评价对青少年学校满意度的影响,采用感知的学校气氛、一般自我概念和学校满意度问卷对320名初中生进行调查,结果表明:初中生学校环境知觉、自我概念与学校满意度呈中等程度显著相关;发展多样性、学习压力、师生关系以及自我概念显著预测学校满意度;环境知觉对学校满意度的方差解释率相对较高,得到了青少年对学校环境知觉和自我评价分别对学校满意度具有显著预测作用的结论。  相似文献   
24.
程序混乱、缺乏研讨氛围、深度不够往往构成参与式培训的障碍。究其原因,一方面在于培训者不能科学设计议题、急于求成,另一方面也是由参与式培训的要求与参与者本身的特点造成,如参与者有根深蒂固的防卫心理、中国人老成持重的性格倾向等。要克服参与式培训的障碍,首先,应科学预设参与议题,做到理论联系实际、难易适度、系统全面;其次,还要做好充分准备、积极创设参与氛围;最后,应有信心,坚持不懈地把参与进行下去,达到目标为止,即参与者思想的充分活跃与思维的充分碰撞。  相似文献   
25.
Afforestation in China provides carbon sequestration and prevents soil erosion, but its remote impacts on climate in other regions via the coupling of forest energy fluxes with atmospheric circulation are largely unknown. Here, we prescribe inventory-based forest cover change and satellite-observed leaf area index from 1982 to 2011 in a coupled land-atmosphere model to simulate their biophysical climate effects. Both local and global surface air temperatures show a seasonal contrast in response to past vegetation cover expansion over China: a phenomenon we primarily attribute to a variation of seasonality of vegetation greening. A large cooling in spring results in concurrent decreases in geopotential height over China and zonal wind over Mongolia, causing a dipole structure in the upper troposphere over the Arctic. This accounts for ∼58% of simulated spring warming over the Russian Arctic and ∼61% of simulated spring cooling over the Canadian Artic. Our results imply that spring vegetation dynamics in China may affect climate in northern high latitudes.  相似文献   
26.
1936—2018年环北极典型流域气温与降水时空变化   总被引:1,自引:0,他引:1  
降水是环北极地区水资源的主要来源。定量分析气温与降水时空变化是深入理解环北极地区陆地水循环过程的基础。本文选取鄂毕河、叶尼塞河、勒拿河流域为对象,利用167个俄罗斯国家气象站点1936—2018年的气温与降水观测数据,结合线性趋势分析和Mann-Kendall突变点检验,揭示环北极典型流域气温与降水的时空变化特征。结果表明:①鄂毕河、叶尼塞河和勒拿河流域多年平均气温为0.06 ℃、-2.98 ℃、-7.41 ℃,年均增温速率分别为0.27 ℃/10 a,0.22 ℃/10 a,0.15 ℃/10 a。年内极端最低温(TNn)上升尤为明显,约为年均增温速率的1.3倍,春、冬季增温速率大于夏、秋两季;②鄂毕河、叶尼塞河和勒拿河流域多年平均降水量为496 mm、428 mm、369 mm;年降水量显著增加,其中叶尼塞河流域增速较慢(3.36 mm/10 a),而鄂毕河(13.02 mm/10 a)和勒拿河(9.59 mm/10 a)流域增速较快,降水增加集中在春、秋、冬三季;③在空间上,增温较快的区域集中在西伯利亚高原和山地,最大增温速率达0.60 ℃/10 a,而平原地区普遍偏低;降水的空间差异大,西伯利亚南部高海拔地区(>1100 m)年降水量达1000 mm左右,北部低海拔地区普遍为300~ 600 mm。上述观测数据指示,环北极流域正在变暖变湿,且空间差异大,可能与“北极放大”及流域下垫面条件有关。  相似文献   
27.
《Sport Management Review》2020,23(4):615-625
The purpose of this study was to investigate influences of environmental and personal factors on volunteers’ behavioral intention. More specifically, the authors examined the relationships among work climate, intrinsic motivation, attitude, emotional exhaustion, and continuance intention through the lens of environmental psychology model. Survey forms tapping the interested outcomes were collected from 924 volunteers of a national sporting event in China. Results of structural equational modeling supported all hypothesized relationships, except the negative relationship between emotional exhaustion and continuance intention. This study expanded the understanding and application of the environmental psychology model in the context of volunteerism in sport.  相似文献   
28.
Background: A distinction is made in Achievement Goal Theory (AGT) between task-oriented (i.e. effort, intra-individual progress, and self-comparison) and ego-oriented (i.e. inter-individual progress and normative comparison) climates. Combining insights from AGT and Self-Determination Theory (SDT), studies in the PE context have shown that a task-oriented climate positively relates to need satisfaction, although the findings regarding the motivating role of an ego-oriented climate are inconsistent. Moreover, little is known about the role of task- or ego-oriented climates in explaining experiences of basic psychological need frustration.

Purpose: Grounded in AGT and SDT, the aim of the present study was to examine if experiences of basic psychological need satisfaction and need frustration can explain why task- and ego-oriented climates elicit positive and negative motivational outcomes in PE, respectively.

Research design: Cross-sectional study.

Method: A sample of 524 secondary school students (51.1% boys, Mage?=?14.51; SD?=?1.81) from five different secondary schools participated in this study. Students reported on their perceptions of task- and ego-oriented climates, motivational regulations, basic psychological need satisfaction, and need frustration, as well as positive and negative outcomes in PE. Structural equation modeling was used to investigate our objective.

Results: We found that a task-oriented climate had a strong and positive relationship with basic psychological need satisfaction, eliciting a bright pathway to autonomous motivation and affective attitude. An ego-oriented climate was positively related to basic psychological need frustration, eliciting a dark pathway to amotivation and boredom. A negative cross-path from task-oriented climate to basic psychological need frustration was also found, while no significant cross-paths were found from ego-oriented climate to basic psychological need satisfaction.

Conclusions: This study provides a better understanding of the mechanisms that explain why task- and ego-oriented climates shape students’ motivational experiences in PE lessons. It is suggested that a task-oriented climate elicits a bright pathway towards more optimal functioning, because it fosters experiences of need satisfaction and buffers against experiences of need frustration. In contrast, an ego-oriented climate is primarily positively related to feelings of need frustration and negative motivational outcomes. Practical implications for PE teacher training are discussed.  相似文献   
29.
我国西部地区非农化的水平低,主要表现在:农业人口以及农村剩余劳动力数量大,农业工业化水平不高,城镇化滞后,市场化率比较低。影响西部地区非农化发展的滞阻因素包括:非农化的制度障碍,非农化的成本障碍,非农化的城乡技术障碍,非农化的主体素质障碍,非农化的观念障碍。加快西部地区非农化的路径选择是:以农业产业化推进西部地区非农化,以农村城镇化带动西部地区的非农化,以农民的知识化促进西部地区的非农化,以剩余劳动力外流化加快西部地区的非农化。  相似文献   
30.
China''s climate has been warming since the 1950s, with surface air temperature increasing at a rate higher than the global average. Changes in climate have exerted substantial impacts on water resources, agriculture, ecosystems and human health. Attributing past changes to causes provides a scientific foundation for national and international climate policies. Here, we review recent progress in attributing the observed climate changes over past decades in China. Anthropogenic forcings, dominated by greenhouse gas emissions, are the main drivers for observed increases in mean and extreme temperatures. Evidence of the effect of anthropogenic forcings on precipitation is emerging. Human influence has increased the probability of extreme heat events, and has likely changed the occurrence probabilities for some heavy precipitation events. The way a specific attribution question is posed and the conditions under which the question is addressed present persistent challenges for appropriately communicating attribution results to non-specialists.  相似文献   
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