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991.
Proteomic analysis of human umbilical vein endothelial cells exposed to PM<Subscript>2.5</Subscript>
Ji Zhu Lin-wen-si Zhu Jin-huan Yang Ying-ling Xu Cui Wang Zhuo-yu Li Wei Mao De-zhao Lu 《Journal of Zhejiang University. Science. B》2018,19(6):458-470
Exposure to fine ambient particulate matter (PM2.5) is known to be associated with cardiovascular disease. To uncover the molecular mechanisms involved in cardiovascular toxicity of PM2.5, we investigated alterations in the protein profile of human umbilical vein endothelial cells (HUVECs) treated with PM2.5 using two-dimensional electrophoresis in conjunction with mass spectrometry (MS). A total of 31 protein spots were selected as differentially expressed proteins and identified by matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) MS. The results demonstrated that DNA damage and cell apoptosis are important factors contributing to PM2.5-mediated toxicity in HUVECs. It is further proposed that PM2.5 can inhibit superoxide dismutase (SOD) activity and increase reactive oxygen species (ROS) and malonaldehyde (MDA) production in a concentration-dependent manner. Induction of apoptosis and DNA damage through oxidative stress pathways may be one of the key toxicological events occurring in HUVECs under PM2.5 stress. These results indicated that the toxic mechanisms of PM2.5 on cardiovascular disease are related to endothelial dysfunction. 相似文献
992.
The purpose of the current study was to investigate a two-stage model in which parent-related stress and hopelessness each served as mediators of the relationship between perceived parental bonding and South Korean adolescent peer victimization. This study also examined whether the mediating relationships differed by the gender of parents and adolescents. A casual chain with three links and four sets of variables were analyzed using structural equation modeling. Data were collected from 800 adolescents attending 10 middle schools in the Busan region of South Korea. Results indicated that both maternal and paternal parental bonding were negatively associated with stress, stress was positively associated with hopelessness, and hopelessness was positively associated with South Korean adolescent peer victimization. Most importantly, the significant negative associations between both maternal and paternal parental bonding and peer victimization were mediated by both stress and hopelessness. Furthermore, gender differences in these relationships existed for both parents and adolescents. Limitations and implications to practice were discussed. 相似文献
993.
Stahmer AC Collings NM Palinkas LA 《Focus on autism and other developmental disabilities》2005,20(2):66-79
Across the country, states are reporting increases in the number of children with autism enrolled in the education system. Although a few specific treatment methods have been established as efficacious for some children with autism in controlled settings, research examining the translation of these treatments into early intervention programs has been minimal. The current study examined provider self-reports of the use of interventions in community settings through focus groups. Providers report the use of both evidence-based and non-evidence-based techniques and indicate that they often combine and modify these techniques based on child, personal, and external factors. Few providers had a clear understanding of evidence-based practice, and all providers reported concerns about adequate training. Implications for early intervention research are discussed. 相似文献
994.
Koen Luwel Joke Torbeyns Lieven Verschaffel 《European Journal of Psychology of Education - EJPE》2003,18(4):425-447
In the research literature several positions concerning the role played by metacognition in adaptive strategy choice can be
distinguished. While many authors adhere so-called metacognitive models of strategy choice and strategy change, others have
questioned the extent to which metacognitive factors are associated with strategy choice and task performance and have proposed
alternative theoretical frameworks wherein strategy choices are described in terms of associative models. In the present article
we report data coming from a larger research project on the development of children’s numerosity judgement strategies and
skills. The experimental task involved judging numerosities of colored blocks presented in a rectangular grid. Participants
were 59 second grade and 50 sixth grade children, whose strategic performance data — obtained by means of a systematic analysis
of their response-time patterns — were compared with interview data collected at the end of the experiment. The major result
of this comparison is that not only the children from the oldest age group, but also the children from the youngest age group
showed clear evidence of metacognitive awareness and understanding of different aspects of their strategic performance. 相似文献
995.
Assessment of Cooperative Learning: A Goal-Criterion Approach 总被引:2,自引:0,他引:2
The problem of assessment of non-traditional teaching techniques has long challenged educational administrators and faculty. The approach to assessment that we followed in this instance employed a model that we developed to assess group learning, variously known as cooperative learning, collaborative learning, or team learning. We applied the model to group-based case study courses that included innovative enhancements such as group exams and group-based role-play. The model required balanced representation among multiple learning criteria arranged in six goal-criterion sets, all drawn from the literature on group learning. We designed a test instrument based on the model and administered the instrument to 85 students near the end of three business strategy courses. Imbalances among criteria in the six goal-criterion sets helped identify and correct weaknesses in course design and in methods of instruction. 相似文献
996.
Influences affecting the soil-water characteristic curve 总被引:2,自引:0,他引:2
INTRODUCTION The soil-water characteristic curve (SWCC) gives the relationship between the amount of water in the soil (i.e. gravimetric or volumetric water content) and soil suction (i.e. matric suction at low suction and total suction at high suction). Many properties of a partially saturated soil such as the coefficient of permeability, shear strength and volume strain, pore size distribution, the amount of water contained in the pores at any suction, can be obtained from the SWCC. … 相似文献
997.
Sonja Haug 《Zeitschrift für Erziehungswissenschaft》2005,8(2):263-284
Zusammenfassung Die Entwicklung der mündlichen und schriftlichen Kenntnisse in Deutsch und der Sprache des Herkunftslandes bei Angeh?rigen
der ersten und zweiten Einwanderergeneration aus den Gastarbeiter-Anwerbel?ndern, bei Aussiedlern und neuen Zuwanderergruppen
wird beschrieben und Erkl?rungsfaktoren für Unterschiede werden mit Hilfe bivariater und multivariater Verfahren untersucht.
Die Deutschkenntnisse der ersten Generation steigen zwischen 1984 und 2001 kaum an, wohingegen Aussiedler und Zuwanderer in
kurzer Zeit relativ gute Fortschritte aufweisen. Die meisten Befragten sind bilingual. Defizite bei Deutschkenntnissen variieren
nach Herkunftsland. Der Zweitspracherwerb erfolgt im Generationenverlauf, d.h. in Deutschland geborene Personen mit Migrationshintergrund
haben in der Regel bessere Deutschkenntnisse als die erste Generation. Die Aufenthaltsdauer hat per se keinen Einfluss auf
den Spracherwerb, ebenso wie das Geschlecht, w?hrend das Einwanderungsalter und die Schulbildung entscheidende Faktoren sind.
Personen mit niedrigem Einwanderungsalter, Personen, die eine weiterführende Schule im Herkunftsland oder eine h?here Schule
in Deutschland abgeschlossen haben, haben eine h?here relative Chance, gute mündliche und schriftliche Deutschkenntnisse zu
erwerben.
相似文献
998.
Mark G. Storz 《The Urban Review》2008,40(3):247-267
In interviews with over 250 urban young adolescents, many students make it clear that they are acutely aware of the educational
inequities that exist in their schools and that these inequities are having a negative impact on their education. Student
voice is used to highlight urban middle school students’ perspectives on the quality of their education particularly in terms
of curricular issues, teacher quality, and lack of resources.
相似文献
Mark G. StorzEmail: |
999.
The Youth in Transition Survey is used to follow the postsecondary education (PSE) pathways and outcomes of Canadian youth over the mid 2000s. Students starting at community colleges and four year universities are analyzed separately. First program outcomes are reported, showing the proportions of students who leave their first programs but remain in PSE by switching/transferring to other programs, institutions, or levels. Multinomial regression estimates correlates of students’ first program switching and leaving decisions. Five year graduation rates are calculated to show the importance of different pathways (across programs, institutions, and levels) to earning a PSE credential; in the aggregate and for subgroups of students. Transfers constitute important but not terribly large pathways for Canadian students to adjust their PSE and obtain PSE credentials. We calculate the resulting extent to which institution specific measures of persistence, PSE leaving, and graduation rates misstate the rates experienced by students. Compared to American students, university and community college starters in Canada have higher persistence and graduation rates and lower transfer rates across institutions. For community college starters, much of the difference is due to the relative lack of well defined pathways from community colleges to universities in Canada. We find that students with more family resources are better able to transfer across programs or institutions in order to obtain a PSE credential. 相似文献
1000.
Marta Civil 《Cultural Studies of Science Education》2016,11(1):41-59
This article examines STEM learning as a cultural process with a focus on non-dominant communities. Building on my work in funds of knowledge and mathematics education, I present three vignettes to raise some questions around connections between in-school and out-of-school mathematics. How do we define competence? How do task and environment affect engagement? What is the role of affect, language, and cognition in different settings? These vignettes serve to highlight the complexity of moving across different domains of STEM practice—everyday life, school, and STEM disciplines. Based on findings from occupational interviews I discuss characteristics of learning and engaging in everyday practices and propose several areas for further research, including the nature of everyday STEM practices, valorization of knowledge, language choice, and different forms of engagement. 相似文献