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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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Jennifer R. Warren Michael L. Hecht David A. Wagstaff Elvira Elek Khadidiatou Ndiaye Patricia Dustman Flavio F. Marsiglia 《Journal of Applied Communication Research》2006,34(2):209-227
This study sought to determine if exposure to two communication-oriented activities, videotapes and public service announcements, accounts for changes in substance use among adolescents participating in the Drug Resistance Strategies Project's keepin' it REAL adolescent substance use prevention curriculum. Middle-school students (4,734, 72% Latino) responded to questionnaires related to these analyses. An analysis of covariance (ANCOVA) model was fit separately to six substance use outcomes. The results suggested that intervention students who saw four or five videos engaged in less substance use in the past month than did students who saw fewer videos. Having seen the PSAs one or more times did not predict the reported change in substance use. 相似文献
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Pushpendra Singh Kuldeep Sharma Dipika Shaw Anudita Bhargava Sanjay Singh Negi 《Indian journal of clinical biochemistry : IJCB》2023,38(4):418
Human Coronaviruses (hCoVs) belongs to the enormous and dissimilar family of positive-sense, non-segmented, single-stranded RNA viruses. The RNA viruses are prone to high rates of mutational recombination resulting in emergence of evolutionary variant to alter various features including transmissibility and severity. The evolutionary changes affect the immune escape and reduce effectiveness of diagnostic and therapeutic measures by becoming undetectable by the currently available diagnostics and refractory to therapeutics and vaccines. Whole genome sequencing studies from various countries have adequately reported mosaic recombination between different lineage strain of SARS-CoV-2 whereby RNA dependent RNA polymerase (RdRp) gene reconnects with a homologous RNA strand at diverse position. This all lead to evolutionary emergence of new variant/ lineage as evident with the emergence of XBB in India at the time of writing this review. The continuous periodical genomic surveillance is utmost required for understanding the various lineages involved in recombination to emerge into hybrid variant. This may further help in assessing virus transmission dynamics, virulence and severity factor to help health authorities take appropriate timely action for prevention and control of any future COVID-19 outbreak. 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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The psychological significance of secondary sexual characteristics in nine- to eleven-year-old girls 总被引:1,自引:0,他引:1
82 9-11-year-old girls were seen in order to study the onset of puberty as represented by breast and pubic hair growth. Girls filled out self-report scales, mothers rated their daughters' breast and pubic hair development using schematic representations of the Tanner stages, and height was measured by a nurse practitioner. Breast growth, but not pubic hair growth, was expected to be associated with a positive body image, positive peer relationships, superior adjustment, and the rating of adult roles as important (marriage, children, and careers). These expectations were confirmed for all but the adult role measures. Controlling for pubic hair growth did not alter the findings for breast development. Associations with height also were examined. Height was linked to superior adjustment and career importance. These findings are discussed in terms of possible roles that different pubertal events may play in the self-definitions of young adolescents as well as the meaning of various physical changes to the girl and to others. 相似文献
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Warren Wollman 《科学教学研究杂志》1984,21(4):399-415
In an exploratory study, education majors in a physical science course were given a set of tasks analogous to a given, solved prototype-task to see how transfer items were handled. Some students were given a conceptual model along with the solved prototype. Others were given a general procedure for applying the conceptual model to the transfer items. The procedure helped considerably for the transfer items least like the prototype item. The model alone was also effective for certain items. In the absence of both model and procedure, students' problem solving was usually incoherent or self-contradictory. Presenting additional solved items helped marginally on an exceptionally novel item. Students' main source of difficulty, given the model and procedure, was that they were distracted by prior, concrete experience and thus failed to follow the procedure. For most students, this difficulty could readily be overcome. A small proportion (10–15%) of students had more profound difficulties. 相似文献