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91.
PURPOSE: Identify journal collection access and use factors. SETTING AND SUBJECTS: University of North Carolina at Chapel Hill's Health Sciences Library patrons. METHODOLOGY: Survey forms and user interactions were monitored once a week for twelve weeks during the fall 1997 semester. The project was based on a 1989 New Mexico State University study and used Kantor's Branching Analysis to measure responses. RESULT: 80% of reported sought journal articles were found successfully. Along with journal usage data, the library obtained demographic and behavioral information. DISCUSSION AND CONCLUSIONS: Journals are the library's most used resource and, even as more electronic journals are offered, print journals continue to make up the majority of the collection. Several factors highlighted the need to study journal availability. User groups indicated that finding journals was problematic, and internal statistics showed people requesting interlibrary loans for owned items. The study looked at success rates, time, and ease of finding journals. A variety of reasons contributed to not finding journals. While overall user reports indicated relatively high success rate and satisfaction, there were problems to be addressed. As the library proceeds in redesigning both the physical space and electronic presence, the collected data have provided valuable direction.  相似文献   
92.
Given the importance of survey measures of online media use for communication research, it is crucial to assess and improve their quality, in particular because the increasingly fragmented and ubiquitous usage of internet complicates the accuracy of self-reported measures. This study contributes to the discussion regarding the accuracy of self-reported internet use by presenting relevant factors potentially affecting biases of self-reports and testing survey design strategies to improve accuracy. Combining automatic tracking data and survey data from the same participants (N = 690) confirmed low levels of accuracy and tendencies of over-reporting. The analysis revealed biases due to a range of factors associated with the intensity of (actual) internet usage, propensity to multitask, day of reference, and the usage of mobile devices. An anchoring technique could not be proved to reduce inaccuracies of reporting behavior. Several recommendations for research practice follow from these findings.  相似文献   
93.
Phonics, fluency, and reading strategy trainings are evidence-based interventions that foster the reading skills of poor readers in primary school. The purpose of the present study was to compare differential effects of the three types of trainings on the efficiency of component processes on word, sentence, and text level immediately after the training and at a 3-month follow-up. The 235 poor readers were randomly allocated to one of the reading interventions or to a control condition. All interventions consisted of 25 sessions that were scheduled twice a week and lasted 45 min. Results indicated short-term effects of the phonics training and the strategy training on the efficiency of a broad range of word-level and sentence-level processes. None of the treatment effects persisted over the long term, indicating the need for instructional efforts to regularly practice the acquired skills after the actual training.  相似文献   
94.
This paper provides evidence of the effects of adult literacy on individuals’ income and employability in Brazil based on information obtained from the monthly employment survey (PME). The OLS results indicate that after controlling for observable characteristics, there is a 21.25% increase in wages for individuals who become literate; however, there is no significant impact on employability. Moreover, the findings show an 8.1% increase in the probability of being employed in the formal sector. We also explore the longitudinal structure of the dataset to control for unobservable fixed characteristics of individuals. The fixed-effects estimators show smaller effects compared to the OLS estimators. We find that literacy has a 4.4% effect on wages and a 4.3% impact on the probability of being formally employed. The effects are significantly different from zero.  相似文献   
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97.
The great contemporary organizational challenge for enterprises is to create a conceptual and methodological framework allows the management of knowledge by means of networks designed for social interaction. This statement is based on the premise that the competitive drive and sustainable success of the company depend on the introduction of new forms of production innovative processes, which can only be ensured through integrated approaches to knowledge management and the incorporation information technologies (IT). This is a reality that has already been accepted by the Brazilian Agricultural Research Corporation (Embrapa, its acronym in Portuguese), a Brazilian research, development, and innovation (RD&I) institution supporting agricultural sector. For some years now, Embrapa has been incorporating what it has learned about knowledge management into its strategic planning process. In this paper, we present a new approach to managing knowledge and information, and we analyze the need for research institutions to administer the knowledge they produce through an RD&I management model based multi- and inter-disciplinary teams, and multi-institutional research networks.  相似文献   
98.
生态伦理及其实践格局   总被引:5,自引:1,他引:5  
生态伦理是一种全新的伦理理念。是由于生态伦理把人与自然之间的价值关系有效地纳入人与人的利益关系中,从而深刻地揭示以自然生态环境中介了的人伦之理,亦即在现实的实践格局中曲折地协调和规范人类多极主体之间的利益关系。人们对此问题的认识上的差异。归根到底反映了不同的历史观和价值观。  相似文献   
99.
For a channel-shoal system in a funnel-shaped basin the impact of dredging and dumping is investigated using a complex process-based model. First, the residual flow and sediment transport circulations are analysed for the channel-shoal pattern, which has emerged after a long-term model simulation. Results are compared to the Western Scheldt estuary, which forms the inspiration for this study. Subsequently, different dredge and dump scenarios are modelled, according to a conceptual model, in which ebb-and flood-channels and enclosed shoals form morphodynamic units (cells) with their own sediment circulation. Model results show that dumping sediment in a channel further reduces the channel depth and induces erosion in the opposite channel, which enhances tilting of the cross-section of the cell and eventually can lead to the degeneration of a multiple channel system into a single channel. The impact of different dredging and dumping cases agrees with results from a stability analysis. This means that this type of model applied to a realistic geometry can potentially be used for better prediction of the impact of human interventions.  相似文献   
100.
Background:Physical activity(PA)has substantial health benefits and is important in combatting chronic diseases,which have been associated with elevated levels of advanced glycation endproducts(AGEs).AGEs play a role in the aging process,and an association between PA and AGEs has been reported.We aimed to investigate the relationship between PA and AGE accumulation in a general population and in a population with chronic diseases.Methods:This large cross-sectional population study used data from adult participants in the LifeLines project,with participant information drawn from the LifeLines database as well data from patients with diabetes mellitus or renal and/or cardiovascular diseases.Tissue AGE accumulation was assessed non-invasively by skin-autofluorescence(SAF)using an AGE reader(DiagnOptics Technologies BV,Groningen,the Netherlands).PA was assessed using the short questionnaire to assess health-enhancing physical activity(SQUASH).Multivariate linear regression analyses were adjusted for age,body mass index,sex,and smoking status.Results:Data from 63,452 participants(general population n=59,177,chronic disease n=4275)were analyzed.The general population was significantly younger(43.58±11.77 years,mean±SD)and had significantly lower SAF(1.90±0.42 arbitrary units(AU))compared to the population with chronic disease(age:55.51±12.07 years;SAF:2.27±0.51 AU).In the group with chronic disease,more hours of moderate to vigorous physical activities per week were associated with lower SAF(β=-0.002,95%confidence interval(95%CI):-0.002 to-0.001).For the general population,there was no association between hours of moderate to vigorous activity and SAF(β=3.2×10-5,95%CI:0.000-0.001,p=0.742).However,there was an association in the general population between total hours of PA per week and SAF(β=4.2×10-4,95%CI:0.000-0.001,p<0.001),but this association was not found in the chronic disease population(β=-3.2×10-4,95%CI:-0.001 to 0.000,p=0.347).Conclusion:Our study demonstrates that an inverse relationship exists between PA and AGE accumulation in the population with chronic disease.More hours of moderate to vigorous activity is associated a significantly decreased SAF.More PA is associated a lower SAF,even after for the established predictors(age,body mass index,smoking status,and sex).Our findings could help to promote health and prolong longevity.  相似文献   
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