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1.
Bibliometric analysis to identify core reference sources of virtual reference transactions 总被引:1,自引:0,他引:1
As the use of electronic reference sources becomes commonplace, virtual reference services are expanding in scope, modes, and popularity. Simultaneously, reference practices are evolving as well. One concept that may be challenged by these trends is the notion of the core reference collection. What are the sources that form this core collection, and what are its characteristics? Are similar sources used to answer users' questions in virtual and traditional reference? How do core collections of public and academic libraries differ? An analysis of 1851 e-mail and chat reference transactions from public and academic libraries reveals that the notion of a core reference collection persists in the world of virtual reference services. In both types of libraries, responses to patrons showed a skewed bibliographic distribution; librarians used a small group of sources to answer most of the questions. Almost all sources used were electronic. Academic libraries tended to make greater use of fee-based sources, but public libraries more often used sources freely-available on the Web. 相似文献
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Kirsty Jayne Elliott-Sale Ashley Graham Stephanie Jane Hanley Sherry Blumenthal Craig Sale 《European Journal of Sport Science》2019,19(1):62-70
AbstractMaternal dietary habits influence maternal and foetal health, representing a pathway for intervention to maximise pregnancy outcomes. Advice on energy intake is provided on a trimester basis, with no additional calories required in the first trimester and an additional 340?kcal?d?1 and 452?kcal?d?1 needed for the second and third trimesters. Energy intake depends on pre-gravid body mass index (BMI); underweight women are recommended an increase of 150, 200 and 300?kcal?d?1 during the first, second and third trimester, normal weight women an increase of 0, 350 and 500?kcal?d?1 and obese women an increase of 0, 450 and 350?kcal?day?1. The recommendations for carbohydrate and protein intake are 175?g?d?1 and 0.88–1.1?g?kgBM?d?1, with no change to fat intake. The number of pre-gravid obese women is rising; therefore, we need to regulate weight in women of childbearing age and limit gestational weight gain to within the recommended ranges [overweight women 6.8–11.3?kg and obese women 5.0–9.1?kg]. This can be achieved using nutritional interventions, as dietary changes have been shown to help with gestational weight management. As pregnancy has been identified as a risk factor for the development of obesity, normal weight women should gain 11.5–16.0?kg during pregnancy. While some research has shown that dietary interventions help to regulate gestational weight gain and promote postpartum weight loss to some extent, future research is needed to provide safe and effective guidelines to maximise these effects, while benefitting maternal and foetal health. 相似文献
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Mehdi Kargarfard Eddie T.C. Lam Ardalan Shariat Ina Shaw Brandon S. Shaw Shamsul B.M. Tamrin 《Journal of sports sciences》2016,34(10):959-965
It is believed that sport massage after intensive exercise might improve power and perceptual recovery in athletes. However, few studies have been done in this area. This study aimed to examine the effect of massage on the performance of bodybuilders. Thirty experienced male bodybuilders were randomly assigned to either a massage group (n = 15) or a control group (n = 15). Both groups performed five repetition sets at 75–77% of 1RM of knee extensor and flexor muscle groups. The massage group then received a 30-min massage after the exercise protocol while the control group maintained their normal passive recovery. Criteria under investigation included: plasma creatine kinase (CK) level, agility test, vertical jump test, isometric torque test, and perception of soreness. All variables were measured over 6 time periods: baseline, immediately after the DOMS inducing protocol, right after the massage, and 24, 48, and 72 h after the massage. Both groups showed significant (P < .001) decreases in jumping, agility performance, and isometric torque, but significant (P < .001) increases in CK and muscle soreness levels. The massage group in general demonstrated a better recovery rate. As such, a post-exercise massage session can improve the exercise performance and recovery rate in male bodybuilders after intensive exercise. 相似文献
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This article focuses on the four primary issues that directly affect service delivery to students with learning disabilities in postsecondary settings, including (a) How are high school and post-secondary settings different? (b) How are eligibility and access determined? (c) How are reasonable accommodations determined? and (d) How can the independence level of college students with learning disabilities be fostered? Each of these issues will be discussed within the context of the student's transition from high school, where Public Law 94-142 is in effect, to college, where Section 504 of the Rehabilitation Act of 1973 applies. 相似文献
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Severe underrepresentation of African-Americansamong postsecondary faculty is often linked toeducational pipeline supply problems,while institutional variations in demandfor black faculty labor and barriers to theirrecruitment and retention receive less empiricalattention. Using a nationally representative sample ofcollege faculty from a wide array of institutions andscience disciplines, this study investigates linksbetween internal organizational conditions and blackfaculty representation. Hypotheses derive from competingexplanations of the role of race in academicorganizations: institutionalized discrimination to protectdominant group privileges; statistical discriminationbased on expectations of racial group differences inacademic preparation; labor supply and politicalconstraints on black faculty recruitment. A multivariateanalysis examines organizational conditions that promoteor curb these dynamics and their relationship to blackappointments at different tenure levels. Results indicate that although the discipline-specificblack doctoral labor supply is a powerful constraint onthe representation of black faculty, selectiveorganizational contexts are substantial influences as well. Although we find little evidence thatinsulation from competition or segmented faculty labormarkets influence the racial composition of faculties,black faculty are more often found whereinstitutionalized discrimination may be checked by greaterformalization and black constituencies on campus.Consistent with statistical discrimination, blackfaculty are poorly represented at research-orientedinstitutions, even controlling for the scholarly reputationof doctoral credentials. 相似文献
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Ellen M. Granger Todd H. Bevis Sherry A. Southerland Yavuz Saka Fengfeng Ke 《科学教学研究杂志》2019,56(3):348-370
This research examines factors influencing elementary science teacher learning as they participate in professional development with and enactment of educative curricula in comparison with learning following limited professional development and enactment of traditional curricula. Using a randomized cluster design (125 teachers and 2,694 students in 4th—5th grades) that met the What Works Clearinghouse standards without reservations, teacher learning was conceptualized using four outcomes. Data were analyzed using standard single-level multiple regression models and possible mediation models for the teacher outcomes were considered using piecewise multiple regression and path analytic approaches. Treatment group teachers experienced greater increases in content knowledge, views of science inquiry, beliefs about reform-based teaching, and teaching self-efficacy than comparison group teachers. The findings indicate that what teachers learn from the combination of professional development and teaching with educative curriculum varies according to what their knowledge and beliefs are on entering the experience. Surprisingly, high entry-level self-efficacy was associated not only with lower learning gains for the teachers, but also for their students. Finally, teachers' space science learning and that of their students are implicated as mediators of the positive effect of the professional development and educative curriculum enactment on teacher beliefs about reform science teaching. This work refines and extends a theoretical framework of teachers' participatory relationship with curricula. 相似文献