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151.
Sovichea Lay Hai-ning Yu Bao-xiang Hu Sheng-rong Shen 《Journal of Zhejiang University. Science. B》2016,17(6):465-475
A pre-treatment methodology for clenbuterol hydrochloride (CLEN) isolation and enrichment in a complex matrix environment was developed through exploiting molecularly imprinted polymers (MIPs). CLEN-imprinted polymers were synthesized by the combined use of ally-β-cyclodextrin (ally-β-CD) and methacrylic acid (MAA), allyl-β-CD and acrylonitrile (AN), and allyl-β-CD and methyl methacrylate (MMA) as the binary functional monomers. MAA-linked allyl-β-CD MIPs (M-MAA) were characterized by Fourier transform-infrared (FT-IR) spectroscopy and a scanning electron microscope (SEM). Based upon the results, M-MAA polymers generally proved to be an excellent selective extraction compared to its references: AN-linked allyl-β-CD MIPs (M-AN) and MMA-linked allyl-β-CD MIPs (M-MMA). M-MAA polymers were eventually chosen to run through a molecularly imprinted solid-phase extraction (MISPE) micro-column to enrich CLEN residues spiked in pig livers. A high recovery was achieved, ranging from 91.03% to 96.76% with relative standard deviation (RSD) ≤4.45%. 相似文献
152.
Menon BR Rathi MA Thirumoorthi L Gopalakrishnan VK 《Indian journal of clinical biochemistry : IJCB》2010,25(4):401-404
The study was designed to evaluate the hepatoprotective activity of ethanolic extract of Bacopa monnieri in acute experimental liver injury induced by Nitrobenzene in rats. The extract at the dose of 200 mg/kg body weight was
administered orally once every day for 10 days. The increased serum marker enzymes, Aspartate transaminase, Alanine transaminase
and alkaline phosphatase were restored towards normalization significantly by the extract. Significant increase in SOD, CAT
and GPx was observed in extract treated liver injured experimental rats. Histopathological examination of the liver tissues
supported the hepatoprotection. It is concluded that the ethanolic extract of Bacopa monieri plant possess good hepatoprotective activity. 相似文献
153.
Spatial visualization ability and laparoscopic skills in novice learners: Evaluating stereoscopic versus monoscopic visualizations 下载免费PDF全文
Victoria A. Roach Manisha R. Mistry Timothy D. Wilson 《Anatomical sciences education》2014,7(4):295-301
Elevated spatial visualization ability (Vz) is thought to influence surgical skill acquisition and performance. Current research suggests that stereo visualization technology and its association with skill performance may confer perceptual advantages. This is of particular interest in laparoscopic skill training, where stereo visualization may confer learning advantages to novices of variant Vz. This study explored laparoscopic skill performance scores in novices with variable spatial ability utilizing stereoscopic and traditional monoscopic visualization paradigms. Utilizing the McGill Inanimate System for Teaching and Evaluating Laparoscopic Skills (MISTELS) scoring protocol it was hypothesized that individuals with high spatial visualization ability (HVz) would achieve higher overall and individual MISTELS task scores as compared to low spatial visualization ability (LVz) counterparts. Further, we also hypothesized that a difference would exist between HVz and LVz individual scores based on the viewing modality employed. No significant difference was observed between HVz and LVz individuals for MISTELS tasks scores, overall or individually under both viewing modalities, despite higher average MISTELS scores for HVz individuals. The lack of difference between scores obtained under the stereo modality suggested that the additional depth that is conferred by the stereoscopic visualization may act to enhance performance for individuals with LVz, potentially equilibrating their performance with their HVz peers. Further experimentation is required to better ascertain the effects of stereo visualization in individuals of high and low Vz, though it appears stereoscopic visualizations could serve as a prosthetic to enhance skill performance. Anat Sci Educ 7: 295–301. © 2013 American Association of Anatomists. 相似文献
154.
Stress analysis of anisotropic thick laminates in cylindrical bending using a semi-analytical approach 总被引:1,自引:0,他引:1
LU Chao-feng LIM C.W. XU Feng 《浙江大学学报(A卷英文版)》2007,8(11):1740-1745
Semi-analytical elasticity solutions for bending of angle-ply laminates in cylindrical bending are presented using the state-space-based differential quadrature method (SSDQM). Partial differential state equation is derived from the basic equations of elasticity based on the state space concept. Then, the differential quadrature (DQ) technique is introduced to discretize the longitu- dinal domain of the plate so that a series of ordinary differential state equations are obtained at the discrete points. Meanwhile, the edge constrained conditions are handled directly using the stress and displacement components without the Saint-Venant principle. The thickness domain is solved analytically based on the state space formalism along with the continuity conditions at interfaces. The present method is validated by comparing the results to the exact solutions of Pagano’s problem. Numerical results for fully clamped thick laminates are presented, and the influences of ply angle on stress distributions are discussed. 相似文献
155.
Catherine Malboeuf-Hurtubise Mireille Joussemet Geneviève Taylor Eric Lacourse 《International Journal of Disability, Development & Education》2018,65(1):33-44
Mindfulness-Based Interventions (MBIs) have been increasingly implemented in schools to foster better emotional regulation skills for students with special education needs such as learning disabilities (LDs). This pilot study aimed to evaluate the impact of a MBI on the need satisfaction of elementary students with severe LDs. A prospective quasi-experimental design involving one group and two time points was employed. A sample of 14 elementary school students from a severe LDs special education class participated in this project. Repeated-measures ANOVAs were conducted and revealed a significant reduction in need satisfaction, with a large effect size (η2 = .35). Contrary to our hypothesis, the MBI appeared to be negatively related to need satisfaction among participants. These results indicate that MBIs could be linked with better self-evaluation skills in students with severe LDs, which, in turn, may change (or increase the accuracy of) the perception that children have of their own need satisfaction. 相似文献
156.
Peter Hatherley-Greene 《Cultural Studies of Science Education》2017,12(2):255-269
Scholars proved nature of science (NOS) has made certain contributions to science teaching and learning. Nonetheless, what, how and how much NOS should be integrated in the science curriculum of each country cannot be a benchmark, due to the influence of culture and society. Before employing NOS in a new context, it should be carefully studied. In assessing views of NOS in Vietnam, a developing country with Eastern culture where the NOS is not consider a compulsory learning outcome, there are several issues that researchers and educators should notice to develop an appropriate instrument that can clearly exhibit a NOS view of Vietnamese. They may include: time for the survey; length, content, type, and terms of the questionnaire; Vietnamese epistemology and philosophy; and some other Vietnamese social and cultural aspects. The most important reason for these considerations is that a Vietnamese view of NOS and NOS assessment possibly differs from the Western ideas due to the social and cultural impact. As a result, a Western assessment tool may become less effective in an Eastern context. The suggestions and implications in this study were derived from a prolonged investigation on Vietnamese science teacher educators and student teachers of School of Education, at Can Tho University, a State University in Mekong Delta region, Vietnam. 相似文献
157.
Thomas Delahunty Niall Seery Raymond Lynch 《Journal of Science Education and Technology》2018,27(2):114-130
Currently, there is significant interest being directed towards the development of STEM education to meet economic and societal demands. While economic concerns can be a powerful driving force in advancing the STEM agenda, care must be taken that such economic imperative does not promote research approaches that overemphasize pragmatic application at the expense of augmenting the fundamental knowledge base of the discipline. This can be seen in the predominance of studies investigating problem solving approaches and procedures, while neglecting representational and conceptual processes, within the literature. Complementing concerns about STEM graduates’ problem solving capabilities, raised within the pertinent literature, this paper discusses a novel methodological approach aimed at investigating the cognitive elements of problem conceptualization. The intention is to demonstrate a novel method of data collection that overcomes some of the limitations cited in classic problem solving research while balancing a search for fundamental understanding with the possibility of application. The methodology described in this study employs an electroencephalographic (EEG) headset, as part of a mixed methods approach, to gather objective evidence of students’ cognitive processing during problem solving epochs. The method described provides rich evidence of students’ cognitive representations of problems during episodes of applied reasoning. The reliability and validity of the EEG method is supported by the stability of the findings across the triangulated data sources. The paper presents a novel method in the context of research within STEM education and demonstrates an effective procedure for gathering rich evidence of cognitive processing during the early stages of problem conceptualization. 相似文献
158.
Kelly Wissman 《Children‘s Literature in Education》2007,38(1):17-34
This article explores how Sandra Cisneros alludes to and recasts popular fairy tales in The House on Mango Street to reveal their troubled legacy in the lives of many women in the novel. Drawing upon Latina feminist theory and Cisneros’s
autobiographical writing, this article posits that the main character Esperanza’s alternative “happily ever after” comes through
locating the vocation of writing as the fulcrum for self-definition and social change. It is suggested that feminist literary
criticism can be enhanced through analysis of heroines from diverse cultural backgrounds and theoretical frameworks attuned
to racial and ethnic diversity.
相似文献
Kelly WissmanEmail: |
159.
160.
Judith A. Martin Ph.D. 《Child abuse & neglect》1984,8(4):387-392
In its examination of violent activity within the family, current literature assumes a “pecking order” exists: Larger and stronger family members attack those who are smaller and weaker. Adult males are usually studied as primary maltreaters of spouses, while females are considered mainly responsible for physically abusive behavior with children. Use of this perspective has led to neglect of male abusers, who injure half of the mistreated children in the United States. Through assessment of 66 studies of child abuse published during a 5-year period, this paper documents the lack of attention abusive fathers have received. Twenty-eight of these studies included only mothers, while two dealt exclusively with fathers. Most of the 36 remaining two-parent studies did not discuss sex differences. No diagnostic categories consistently differentiated male from female abusers. No study discussed specialized treatment needs of women and men. This survey suggests that the therapeutic field considers the child's mother the primary responsible parent, even though she may not be the perpetrator of violence in the family. As a result, inadequate treatment resources have been made available to maltreating fathers. The survey points to the need for much more comprehensive research comparing male and female maltreaters. 相似文献