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31.
Hafen CA Allen JP Mikami AY Gregory A Hamre B Pianta RC 《Journal of youth and adolescence》2012,41(3):245-255
Student engagement is an important contributor to school success, yet high school students routinely describe themselves as
disengaged. Identifying factors that alter (increase) engagement is a key aspect of improving support for student achievement.
This study investigated students’ perceptions of autonomy, teacher connection, and academic competence as predictors of changes
in student engagement within the classroom from the start to the end of a course. Participants were 578 (58% female) diverse
(67.8% White, 25.2% African American, 5.1% Hispanic, 1.2% Asian American) high school students from 34 classrooms who provided
questionnaire data both at the start and the end of a single course. Novel results from a cross-lagged model demonstrated
that students who perceived their classrooms as allowing and encouraging their own autonomy in the first few weeks increased
their engagement throughout the course, rather than the typical decline in engagement that was demonstrated by students in
other classrooms. This finding is unique in that it extended to both students’ perceptions of engagement and observations
of student engagement, suggesting a fairly robust pattern. The pertinence of this finding to adolescent developmental needs
and its relationship to educational practice is discussed. 相似文献
32.
Vangie A. Foshee Thad S. Benefield Heath Luz McNaughton Reyes Susan T. Ennett Robert Faris Ling-Yin Chang Andrea Hussong Chirayath M. Suchindran 《Journal of youth and adolescence》2013,42(4):471-486
The peer context is a central focus in research on adolescent risk behaviors but few studies have investigated the role of the peer context in the perpetration of adolescent dating violence. This longitudinal study examined between-subjects and within-person contemporaneous and lagged effects of peer attributes, measured with social network analyses, on trajectories of dating violence perpetration and determined if effects varied by grade and/or sex of the adolescent. Data are from adolescents who participated in a five-wave panel study beginning when they were in 7 through 9th grade and ending when they were in 10 through 12th grade (n = 3,412); half were male, 40.5 % were white, 49.9 % were black and 10.4 % were of another race/ethnicity. Significant between-subjects effects indicate that adolescents who typically have friends who use dating violence, and girls who are typically high in social status, are at increased risk for using dating violence throughout adolescence. Adolescents who typically have high quality friendships and girls who typically have friends with pro-social beliefs are at decreased risk for using dating violence throughout adolescence. Significant within-person contemporaneous effects indicate that both boys and girls reported lower levels of dating violence than usual at times when they had more friends with pro-social beliefs, and reported higher levels of dating violence than usual at times when they had higher social status. None of the lagged effects were significant and none of the effects varied across grade. These findings suggest that the peer context plays an important role in the development of the perpetration of adolescent dating violence. 相似文献
33.
Ha-Joon Chang 《The Journal of peasant studies》2013,40(3):477-515
This article reviews the histories of agricultural policy in 11 of today's developed countries between the late-nineteenth and the mid-twentieth century and in 10 developing and transition economies since the mid-twentieth century. After discussing the theoretical limitations of the prevailing orthodoxy, the article discusses the history of a wide range of agricultural policies concerning issues like land, knowledge (e.g., research, extension), credit, physical inputs (e.g., irrigation, transport, fertilizers, seeds), farm income stability (e.g., price stabilisation measures, insurances, trade protection), marketing, and processing. The article ends by discussing the policy lessons that may be learned from these historical experiences. 相似文献
34.
35.
Minji Lee M.S. Ju Yeon Jung M.S. Sungsoo Choi M.S. Ilung Seol Ph.D. Seohyun Moon Ph.D. In Kwan Hwang Ph.D. 《Journal of forensic sciences》2020,65(6):2117-2120
Lophophora is a member of the Cactaceae family, which contains two species: Lophophora williamsii and L. diffusa. Lophophora williamsii is an illegal plant containing mescaline, a hallucinogenic alkaloid. In this study, a novel method based on a single nucleotide polymorphism (SNP) assay was developed for identifying L. williamsii; this assay reliably detects SNPs within chloroplast DNA (rbcL, matK, and trnL-trnF IGS) and was validated for identifying Lophophora and L. williamsii simultaneously. The chloroplast DNA sequences from four L. williamsii and three L. diffusa plants were obtained and compared using DNA sequence data from approximately 300 other Cactaceae species available in GenBank. From this sequence data, a total of seven SNPs were determined to be suitable for identifying L. williamsii. A multiplex assay was constructed using the ABI PRISM® SNaPshot™ Multiplex Kit (Applied Biosystems, Forster City, CA) to analyze species-specific SNPs. Using this multiplex assay, we clearly distinguished the Lophophora among 19 species in the Cactaceae family. Additionally, L. williamsii was distinguished from L. diffusa. These results suggest that the newly developed assay may help resolve crimes related to illegal distribution and use. This multiplex assay will be useful for the genetic identification of L. williamsii and can complement conventional methods of detecting mescaline. 相似文献
36.
Wu-ting Tsai Ph.D. Chia-I Hu M.S. Chia-Yun Chang L.L.M. 《Journal of forensic sciences》2020,65(1):255-258
The horizontal displacement of the human body resulting from fatal fall from a height is an important variable commonly used to inversely determine the cause or identify other forensic aspects of the fall. When examining the horizontal displacement, the wind effect is generally ignored. This technical note reports analytical modeling of the falling process, utilizing previous measurements of wind force acting on the human body, for determining the functional relationship between the wind speed and the horizontal displacement in the falling process. The result reveals that it does not take extremely rare wind conditions to cause a considerable shift of the human body, highlighting the importance to consider wind as a factor in investigations of fatal falls. 相似文献
37.
Hari Jang M.S. Sang Eon Shin Ph.D. Kyu Jin Youm B.S. Mustafa Zafer Karagozlu Ph.D. Chang Bae Kim Ph.D. Kwang Soo Ko M.S. Seong Hwan Park M.D. Ph.D. 《Journal of forensic sciences》2020,65(1):283-287
Species identification of necrophagous insects found on a dead body is an essential key in applying medicolegal entomology to the estimation of postmortem interval (PMI). Due to limited morphological identification of insect evidence, several studies have identified species using molecular information such as DNA markers. While considerable cytochrome c oxidase subunit I (COI) gene sequence data of necrophagous fly species have been collected and annotated, those of necrophagous beetle species have not. Since necrophagous beetles such as Dermestes species have a larval period longer than that of flies, beetles are useful in even the late decomposition phase in estimating minimum PMI. To obtain the full-length COI gene sequences of six Dermestes species collected from South Korea, we designed primers for polymerase chain reaction amplification and sequencing. The obtained full COI nucleotide sequences were used for performing phylogenic analysis and comparison with previously reported sequences. The results demonstrated that the COI gene sequences could be used to identify forensically important Dermestes species in South Korea. 相似文献
38.
Ju Yeon Jung M.S. Ga Hee Ryu B.S. Da-Hye Kim B.S. Joo-Young Kim Ph.D. In Kwan Hwang Ph.D. Pil-Won Kang Ph.D. Byung Won Chun Ph.D. Seong Yeon Yoo Ph.D. 《Journal of forensic sciences》2020,65(1):209-213
When using non-FTA cards in commercial multiplex STR kits for direct PCR, pretreatment steps with specific buffers are recommended. Here, we designed a rapid direct PCR method utilizing a non-FTA card, Oral Cell Sampling Kit, by omitting the pretreatment step involving Prep-n-Go™ Buffer, and it showed compatibility with the GlobalFiler™ Express PCR Amplification Kit, GlobalFiler™ PCR Amplification Kit, and PowerPlex® Fusion system. To optimize the PCR conditions, we tested the method with different final PCR volumes and cycles. Finally, we conducted a performance test using 50 Korean buccal samples and confirmed the high performance of the method, detecting more than 90% of the samples with full profiles when using GlobalFiler™ PCR Amplification Kit and PowerPlex® Fusion system at 29 cycles in a 10 μL final PCR volume. Thus, we report a simple direct PCR set-up to analyze reference samples collected using a non-FTA card manufactured in Korea. 相似文献
39.
Duell Natasha Steinberg Laurence Icenogle Grace Chein Jason Chaudhary Nandita Di Giunta Laura Dodge Kenneth A. Fanti Kostas A. Lansford Jennifer E. Oburu Paul Pastorelli Concetta Skinner Ann T. Sorbring Emma Tapanya Sombat Tirado Liliana Maria Uribe Alampay Liane Peña Al-Hassan Suha M. Takash Hanan M. S. Bacchini Dario Chang Lei 《Journal of youth and adolescence》2019,48(4):835-836
Journal of Youth and Adolescence - In the original publication, the legends for Figs 4 and 5 were incorrect, such that each regression line was mislabeled with the incorrect country. Below are the... 相似文献
40.
Esther S. Chang Jutta Heckhausen Ellen Greenberger Chuansheng Chen 《Journal of youth and adolescence》2010,39(11):1293-1304
This study proposed and confirmed three ways in which college students can perceive shared agency and two ways in which they can perceive non-shared agency with parents when pursuing educational goals in college. Differences and similarities were examined among participants
from four ethnic backgrounds (N = 515; 67% female): East Asian American, Southeast Asian American, Filipino/Pacific Islander American, and European American.
Results indicated that Asian American youth reported higher levels of non-shared agency with parents (i.e., parental directing
and noninvolvement), lower levels of shared agency (i.e., parental accommodation, support, or collaboration), and poorer college
adjustment compared to European Americans. However, ethnic similarities were found whereby perceived shared agency in education
with parents was associated with college adjustment. Multiple mediation analyses also indicated that our model of shared and
non-shared agency with parents explained differences in college adjustment between Asian and European Americans, though more
strongly for comparisons between European and East Asian Americans. Our results suggest that parents continue to be important
in the education of older youth but that continued directing of youth’s education in college can be maladaptive. 相似文献