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1.
Nearly one in four students residing in the United States is from an immigrant family and these children's school readiness is related to their parent's nativity and other sociodemographic characteristics. Social‐emotional skills are an important conduit for academic development, yet these relations have not been explored for children from immigrant families. This study utilized the Early Childhood Longitudinal Study—Kindergarten Class of 2010–2011, a nationally representative sample of 13,400 students in the United States, to compare the social‐emotional development of kindergarten students from immigrant and nonimmigrant families, and to determine the relations of social‐emotional functioning to kindergarten achievement. Results indicate elevated social‐emotional functioning among children from immigrant families, particularly those who emigrated immigrated from Mexico, compared with children of U.S.‐born parents. Parent nativity predicted reading achievement, but not mathematics performance, even when controlling for sociodemographic factors and social‐emotional skills. This study suggests an immigrant advantage in early social‐emotional development. Implications for research and practice are discussed.  相似文献   
2.
We report on low-cost fabrication and high-energy density of full-cell lithium-ion battery (LIB) models. Super-hierarchical electrode architectures of Li2SiO3/TiO2@nano-carbon anode (LSO.TO@nano-C) and high-voltage olivine LiMnPO4@nano-carbon cathode (LMPO@nano-C) are designed for half- and full-system LIB-CR2032 coin cell models. On the basis of primary architecture-power-driven LIB geometrics, the structure keys including three-dimensional (3D) modeling superhierarchy, multiscale micro/nano architectures and anisotropic surface heterogeneity affect the buildup design of anode/cathode LIB electrodes. Such hierarchical electrode surface topologies enable continuous in-/out-flow rates and fast transport pathways of Li+-ions during charge/discharge cycles. The stacked layer configurations of pouch LIB-types lead to excellent charge/discharge rate, and energy density of 237.6 Wh kg−1. As the most promising LIB-configurations, the high specific energy density of hierarchical pouch battery systems may improve energy storage for long-driving range of electric vehicles. Indeed, the anisotropic alignments of hierarchical electrode architectures in the large-scale LIBs provide proof of excellent capacity storage and outstanding durability and cyclability. The full-system LIB-CR2032 coin cell models maintain high specific capacity of ∼89.8% within a long-term life period of 2000 cycles, and average Coulombic efficiency of 99.8% at 1C rate for future configuration of LIB manufacturing and commercialization challenges.  相似文献   
3.
This paper proposes an optimization scheme for optimal configuration and energy management of the micro-grid (MG), using the Cuckoo search optimization algorithm (CSOA). The selected MG supplies a load profile located between 30.119 latitude and 31.605 longitude. The energy produced by the MG generation sources, according to meteorological data of the proposed location, is calculated using MATLAB. The objective/fitness function is modeled and designed for minimizing the total investment cost (TIC) including capital, investment, operation and maintenance costs. A novel weighted goal attainment function (WGAF) has been proposed to reduce CO2 emissions and their associated costs. Moreover, WGAF also applies higher taxes on the amount of emissions that exceed governmental approved limits. To investigate the effects of WGAF on the TIC ($/year), annual cost of energy ($/kWh), and CO2 emissions, various weighted coefficients are analyzed. The simulation results have shown that the designed optimization scheme can robustly and efficiently produce the optimal MG configuration that is both eco-friendly and generates economic benefits.  相似文献   
4.
Exposure to various organic compounds including drugs and environmental toxins causes cellular damage through generation of free radicals. Carnosine a dipeptide was used in this study to evaluate its effect against CCl4-induced nephrotoxicity. Sixty male albino rats were involved in this study and were equally divided into four groups. CCl4 (3 ml/kg body weight; biweekly for 4 weeks) was given to group II and III. Carnosine (10 mg/kg body weight; once daily for 4 weeks) was given to group III and VI. Transforming growth factor-β1 (TGF-β1) level by immunoassay and Smad3 mRNA level by real-time PCR were estimated in addition to cytochrome P450 2E1 (CYP2E1) activity, renal functions, redox status assessment and histopathological examination of the kidney. Carnosine significantly improved kidney function, renal redox status, decreased renal CYP2E1 activity, TGF-β1 level and Smad3 gene expression when compared to CCL4-intoxicated group. The protective effect of carnosine was confirmed by histopathological study. In conclusion: carnosine has the ability to protect against CCl4-induced nephrotoxicity possibly by alleviating oxidative stress, normalizing kidney histopathological architecture in addition to the disruption of the inflammatory and fibrotic response induced by CCl4.  相似文献   
5.
This case–control study is aimed to evaluate serum concentration of Cyclin-Dependent Kinase 6 (CDK6) and the genetic association between rs2237572 CDK6 gene and breast cancer (BC) in Iraq. To attain this goal, 80 patients with BC as cases and 80 healthy individuals as controls were included. Further, BC patients were sorted according to the molecular classification into four subtypes of Luminal A, Luminal B, Her2/neu enriched and TPN. Serum concentration of CDK6 enzyme, allelic and genotypic frequencies of rs2237572 CDK6, and the occurrence of BC phenotype and its subtypes in the studied population were investigated. ELISA technique was used to perform the biochemical testing, while the molecular analysis was achieved by real-time PCR, high resolution melting analysis, conventional PCR, as well as sequencing analysis. The results revealed no significant difference in serum concentration of CDK6 enzyme between patients and healthy controls (p > 0.05). Also, no significant differences were shown between BC patients subtypes (p > 0.05). The rs2237572 CDK6 genotypes were associated with the BC and affirmed that allele C was inherited as a recessive risk factor. Moreover, a highly significant difference between patients’ subtypes in the genotypic frequency of rs2237572 (p < 0.01) was noted. Furthermore, the association of rs2237572 genotypes and CDK6 serum concentration in BC patients showed a considered significant difference between C/C and T/T, C/C and T/C and the CDK6 level (p < 0.05). Nevertheless, T/T and T/C did not show any significant difference with the CDK6 level. Hence, it was concluded that the rs2237572 of CDK6 gene is significantly correlated with BC.  相似文献   
6.
Education and Information Technologies - During the ongoing coronavirus disease 2019 pandemic, over 1.5&nbsp;billion students worldwide have been deprived of access to traditional learning....  相似文献   
7.
Acculturative stress is a common experience for international students and is associated with psychological and physical problems. In a previous study (Tavakoli et al. Journal of Counseling Psychology 56:590-596, 2009), the authors reported that two stress reduction interventions—expressive writing (EW) and assertiveness training (AT)—had limited overall benefits among international students at an American University. The current analyses of data from that study investigated whether individual differences moderated the effects of EW and AT. Results indicate that greater acculturative stress at baseline predicted greater improvement from both interventions. Additionally, women benefited more from AT than EW, except that EW improved women’s physical symptoms. Men benefited more from EW than AT. Students with limited emotional awareness and expression tended to benefit from both interventions. Finally, nation of origin cultural differences generally did not predict outcomes. It is concluded that the benefits of EW and AT can be enhanced by targeting these interventions to specific subgroups of international students.  相似文献   
8.
The current study seeks to introduce a new pedagogical design for geo-informatics courses using an e-training support system. Laurillard’s conversational approach based on conceptual representation for both instructor and learner was used to form the framework. As the current study specifically interested in training as a special form for learning, so, we sought methods and strategies to integrate requirements of both company and employee into the design of training programs. Therefore, a competency perspective was adopted into the conversational framework to use learning design that leads to learning activities tightly related to the needs of the company and employee. The above framework has been developed with special consideration to the underpinning pedagogical principles and the needs of lifelong learning that continues after the training has been completed. The implementation of the developed framework needs a special computerized system, so an e-training support system (ETSS) was developed to realize the framework. ETSS is an open source and standard-based infrastructure to enable and foster competence development and exchange of learning activities and learning units. Although the domain of the current study focuses on geo-informatics, ETSS is applicable to any other domain. The developed framework through its ETSS implementation were evaluated in a typical training environment. The results indicated that the best method in training was the training with the developed system with 91.5 % in comparison with the traditional training method with 81.4 %.  相似文献   
9.
Although research emphasizes the importance of integrating technology into the curriculum, the use of technology can only be effective if teachers themselves possess the expertise to use technology in a meaningful way in the classroom. The aim of this study was to assist Egyptian teachers in developing teaching and learning through the application of a particular digital technology. Students were encouraged to work through the process of producing their own digital stories using MS Photo Story, while being introduced to desktop production and editing tools. They also presented, published and shared their own stories with other students in the class. Quantitative and qualitative instruments, including digital story evaluation rubric, integration of technology observation instruments and interviews for evaluating the effectiveness of digital storytelling into learning were implemented to examine the extent to which students were engaged in authentic learning tasks using digital storytelling. The findings from the analysis of students-produced stories revealed that overall, students did well in their projects and their stories met many of the pedagogical and technical attributes of digital stories. The findings from classroom observations and interviews revealed that despite problems observed and reported by teachers, they believed that the digital storytelling projects could increase students’ understanding of curricular content and they were willing to transform their pedagogy and curriculum to include digital storytelling.
Alaa SadikEmail: Email:
  相似文献   
10.
This article's purpose is to analyze the current state of library websites in academic institutions in Gulf Cooperative Council (GCC) countries, aiming to determine their compliance with standard website practices. Based on the Library Website Evaluation Checklist (L-WEC) developed for this study, a content analysis is performed of 110 academic library websites. This research, being one of the first studies of its kind, should interest information professionals and educators responsible for developing and improving the quality of their websites. With the majority of academic users growing up in the Google generation, it is important to create more millennial-friendly websites that provide quick and easy access to Web-based services and content-rich information.  相似文献   
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