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901.
Note taking is the core activity for students in a classroom. There has been a large amount of research conducted, both from industry and from academia, into facilitating the note-taking process. There is evidence that shows that note taking can be beneficial for the students’ educational growth. There are also many available systems for taking notes electronically (e.g. Tablet PCs, PDAs). However, what has not been given as much attention is how these electronic devices affect (or support) the note taking task. In this paper, we study university students’ current note taking behavior and the changes caused by the use of electronic systems for this activity. The goal of our work is to identify issues that should be considered when evaluating electronic note taking systems and to formulate requirements for future electronic note-taking systems. Our findings show that while the technological support for writing with pens on electronic surfaces is quite advanced, the task of note taking in the classroom is not well supported. We identify the limitations of typical note taking systems and discuss the implications for the design of future note taking systems. Our work consisted of three parts: a survey of current note-taking practices, an observational study in a classroom environment, and a semester long case study of students using electronic note-taking devices. All of these activities took place at a large 4-year university. We found that the people reacted to note-taking devices very differently and that their current practices were not always well supported. The users all wanted to input information as fast as possible, in the manner they wanted but they were not always able to achieve that. Hardware limitations (i.e. screen size, responsiveness) added to this issue. We also found that the features that are well supported in an electronic medium (i.e. modification, reorganizing, multiple pen colors/styles, handwriting recognition, sharing) were not commonly used or wanted.  相似文献   
902.
903.
The increasingly serious problem of acid rain is leading to increased potassium (K) loss from soils, and in our field investigation, we found that even congenerically relative Mosla species show different tolerance to K-deficiency. A hydroponic study was conducted on the growth of two Mosla species and their morphological, physiological and stoichiometric traits in response to limited (0.35 mmol K/L), normal (3.25 mmol K/L) and excessive (6.50 mmol K/L) K concentrations. Mosla hangchowensis is an endangered plant, whereas Mosla dianthera a widespread weed. In the case of M. hangchowensis, in comparison with normal K concentration, K-limitation induced a significant reduction in net photosynthetic rate (P n), soluble protein content, and superoxide dismutase (SOD) activity, but an increase in malondialdehyde (MDA) concentration. However, leaf mass ratio (LMR) and root mass ratio (RMR) were changed little by K-limitation. In contrast, for M. dianthera, K-limitation had little effect on P n, soluble protein content, SOD activity, and MDA concentration, but increased LMR and RMR. Critical values of N (nitrogen): K and K:P (phosphorus) ratios in the shoots indicated that limitation in acquiring K occurred under K-limited conditions for M. hangchowensis but not for M. dianthera. We found that low K content in natural habitats was a restrictive factor in the growth and distribution of M. hangchowensis, and soil K-deficiency caused by acid rain worsened the situation of M. hangchowensis, while M. dianthera could well acclimate to the increasing K-deficiency. We suggest that controlling the acid rain and applying K fertilizers may be an effective way to rescue the endangered M. hangchowensis. Project supported by the National Natural Science Foundation of China (No. 30570113) and the Research Fund for the Doctoral Program of Higher Education (No. 20060335008), China  相似文献   
904.
This study tested the longitudinal association between perceptions of racial discrimination and racial identity among a sample of 219 African American adolescents, aged 14 to 18. Structural equation modeling was used to test relations between perceptions of racial discrimination and racial identity dimensions, namely, racial centrality, private regard, and public regard at 3 time points. The results indicated that perceived racial discrimination at Time 1 was negatively linked to public regard at Time 2. Nested analyses using age were conducted, and perceptions of racial discrimination at Time 2 were negatively linked to private regard at Time 3 among older adolescents. The findings imply that perceived racial discrimination is linked to negative views that the broader society has of African Americans.  相似文献   
905.
Advancing reflective judgment through Socioscientific Issues   总被引:1,自引:0,他引:1  
The purpose of this investigation was to explore possible relationships between Socioscientific Issues instruction and students' development of reflective judgment. The usefulness of the Reflective Judgment Model as a tool for assessing the value of SSI is established in the parallels that can be drawn between them. Both involve ill‐structured problems requiring evidence‐based reasoning subject to differing interpretations by students, and both require examination, analysis and the blending of scientific and normative evidence, as students use that evidence to support a reasoned position. Results demonstrated both qualitative evidence revealing more sophisticated and nuanced epistemological stances toward higher stages of reflective judgment, as well as statistically significant gains within treatment groups with a moderately large effect size. Theoretical implications for advancing students' epistemological beliefs about evidence‐based argumentation and pedagogical implications for rethinking how to connect science with topics that are fundamentally meaningful to students are discussed. © 2008 Wiley Periodicals, Inc. J Res Sci Teach 46: 74–101, 2009  相似文献   
906.
907.
BackgroundThe appropriate use of antiretroviral medications to protect against infection with human immunodeficiency virus (HIV) is unclear in cases of sexual assault of children, for whom the perpetrator's risk of HIV is often unknown, and physical proof of sexual contact is usually absent.ObjectiveIn an effort to clarify prescribing practices for HIV post-exposure prophylaxis (PEP) at our institution, we examined records of all children tested for HIV for prevalence of infection, our experience with prescribing PEP, and follow-up rates.Design/methodsMedical records at a sexual abuse clinic of all children tested for HIV during a 38-month period were reviewed for information concerning risk factors for HIV acquisition, STI test results, and PEP experience. Children were defined as PEP-eligible if they were within 96 hours of assault, and there was a report of sexual contact with the potential to transmit HIV.ResultsOne thousand seven hundred and fifty children were tested for HIV during the study period. Five children had a positive HIV ELISA, but only one child was confirmed HIV-positive. Three hundred and three children were eligible to receive HIV-PEP, but it was only offered to 16 (5.3%), of whom 15 accepted the medications. None of the children prescribed PEP completed follow-up, but 11 children had limited follow-up.ConclusionsOur results indicate that the prevalence of HIV infection among sexually abused children in our population is low, and follow-up rates are poor. Intensive efforts to try to ensure follow-up are warranted whenever PEP is prescribed. Further research may help better define the efficacy of PEP in sexually abused children and adolescents.  相似文献   
908.
We investigated the use of adaptive comparative judgment to evaluate the middle school student learning, engagement, and experience with the design process in an open-ended problem assigned in a technology and engineering education course. Our results indicate that the adaptive comparative judgment tool effectively facilitated the grading of the students’ products and improved the judges’ understanding of the processes the students used to arrive at their solutions. We found the reliability and validity of the tool to be acceptable and the outcomes of our study suggest that there is justification for the use of the adaptive comparative judgment method to assess student learning outcomes at multiple levels of Science, Technology, Engineering, and Math (STEM) education.  相似文献   
909.
Developmental trauma—distressing childhood experiences that include mistreatment, interpersonal violence, abuse, assault, and neglect—is associated with substance use and poor academic performance. The authors investigated the links between developmental trauma, grade point average, substance use, and resilience among first‐year college students (N = 169). The results indicate there is a significant relationship between cumulative trauma and self‐reported substance use.  相似文献   
910.
This study addressed the extent to which pre-service teachers at a teachers’ college in the United Arab Emirates (UAE) accepted and intended to utilize technology-rich learning environments in their future teaching practice. The effect of other significant factors on their overall acceptance, such as computer self-efficacy (CSE) and Perceived User Resources, was investigated. A final aim was to confirm the applicability of the instruments employed in this study within the unique sociocultural context of the UAE. Questionnaires utilizing a modified version of the technology acceptance model (TAM) were used to collect data. Respondents indicated strong acceptance of technology-rich learning environments. In the model, Perceived Usefulness and CSE were the two strongest predictors of Behavioral Intention. The results also supported the validity of TAM-based research within the Emirati sociocultural environment.  相似文献   
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