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951.
Andean Indians have used coca leaves (Erythroxylon coca and related species) for centuries to enhance physical performance. The benefits and disadvantages of using coca leaf have been a subject of many political debates. The aim of this study was to investigate the effects of chewing coca leaves on biochemical and physiological parameters. Cutaneous microdialysis catheters were used to estimate systemic biochemical changes. We subjected 10 healthy adult males (local residents) in Cajamarca (Peru, altitude 2700 m) to a standardised exercise routine on a stationary cycle ergometer. The blood pressure, oxygen saturation (digital), pulse, VO2 max and ECG (Holter monitor) were recorded before the exercise. Cutaneous microdialysis catheters were introduced in the forearm. The subjects were given to chew 8 g of coca leaves with a small amount of lime. They were then placed on the cycle ergometer for 20 min. Blood pressure, oxygen saturation, pulse, ECG and VO2 max were recorded. Pyruvate, glucose, lactate, glycerol and glutamate levels were estimated. Oxygen saturation, blood pressure, and pulse rate did not show any significant changes between the two groups. Glucose levels showed hyperglycaemic response. Glycerol, Lactate and Pyruvate increased. Glutamate remained unchanged. Similar changes were not seen in the controls. These results suggest that coca leaves have blocked the glycolytic pathway of glucose oxidation resulting in accumulation of glucose and pyruvate. The energy requirement for exercise is being met with beta-oxidation of fatty acids. The glycerol released was also getting accumulated since its pathway for oxidation was blocked. These experimental findings suggest that chewing coca leaves is beneficial during exercise and that the effects are felt over a prolonged period of sustained physical activity.  相似文献   
952.
Time-in and time-out were used to treat inappropriate and noncompliant behaviors in a child with severe language disabilities and a child with a moderate mental disability and cerebral palsy. The target behaviors for Jeremy were compliance with first-time presented teacher instructions, elopement and aggression. Prior to intervention, archival baseline data for Jeremy suggested a compliance rate with teacher directives of approximately 9% and a high frequency of elopement and aggression. Following implementation of a compliance training package, compliance to teacher directives increased to 97% within the first week of intervention and minimal instances of elopement and aggression. Two, 24, and 40-week follow-up compliance checks yielded mean rates of 98%, 99%, and 98% respectively and no elopement or aggression. Reduction in object tossing behaviors was targeted for Jenny. Archival baseline, indicated through parent report, suggested tossing rates of 80% of the times objects were in hand. Frequency of object tossing behavior decreased to a near-zero level during intervention. The use of this intervention package with children in an effort to deter future chronic noncompliance and inappropriate behavior is discussed. © 1997 John Wiley & Sons, Inc.  相似文献   
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This article proposes that states create low-income targeted voucher programs for 3- and/or 4-year-olds. The basis for this proposal is considerable research demonstrating long-term effects for a number of random assignment and quasi-experimental preschool programs. Benefit–costs rates of return for these programs are between $2 and $16 for every dollar invested. These results are also consistent with developmental and neuro-biological studies supporting early childhood interventions. Other research shows that low-income students are less likely to be in preschool, and if they are, they are more likely to receive low-quality services. Taken together, and to control costs, I propose an income-targeted program. I argue for vouchers based on improved equal opportunity and higher efficiency in the delivery of preschool services. Design details are generally to be the province of state decision makers. My one caveat is that it seems to make sense to require programs, at least for 4-year-olds, to be center based.  相似文献   
956.
In order to meet both in‐service and pre‐service training needs in gerontology, North Country Community College has developed an innovative one‐year certificate program. Under the assumption that persons working with the aged in a rural area must have a diverse group of skills to draw upon, the gerontology certificate stresses course work in: communication skills, culture variability, gerontology knowledge, management skills, and service skills. The curriculum approach taken is that of competency based education, with most of the skills courses put into a modular course format. After the first year of the certificate, 53% (N = 65) of the students in the certificate courses are adults or community professionals turning to this community college program to upgrade skills or acquire new ones. This certificate is beginning to meet the training needs in a rural area that were only previously addressed by occasional workshops for the human service practitioner.  相似文献   
957.
In planning for a new library construction project for the University of Oklahoma-Tulsa, graduate students enrolled in the University of Oklahoma (OU) School of Library and Information Studies collaborated in an innovative effort to develop a commons-based reference service. By first considering a philosophical approach to the need for a commons, blending in the experiences of other libraries that have created similar spaces, and focusing on the workflow issues likely to be encountered by the graduate assistants staffing the commons itself, this planning team developed an uncommon peer-to-peer approach to reference and education services, one focused on the patron as student.  相似文献   
958.
This paper introduces a new impact indicator for the research effort of a university, nh3. The number of documents or the number of citations obtained by an institution are used frequently in international ranking of institutions. However, these are very dependent on the size and this is inducing mergers with the apparent sole goal of improving the research ranking. The alternative is to use the ratio of the two measures, the mean citation rate, that is size independent but it has been shown to fluctuate along the time as a consequence of its dependence on a very small number of documents with an extremely good citation performance. In the last few years, the popularity of the Hirsch index as an indicator of the research performance of individual researchers led to its application to journals and institutions. However, the original aim of this h index of giving a mixed measure of the number of documents published and their impact as measured by the citations collected along the time is totally undesirable for institutions as the overall size may be considered irrelevant for the impact evaluation of research. Furthermore, the h index when applied to institutions tends to retain a very small number of documents making all other research production irrelevant for this indicator. The nh3 index proposed here is designed to measure solely the impact of research in a way that is independent of the size of the institution and is made relatively stable by making a 20-year estimate of the citations of the documents produced in a single year.  相似文献   
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PURPOSE: The study seeks to determine how medical library professionals performing information-technology (IT) roles are compensated and how their positions are designed compared to information technology staff in their institutions. METHODS: 550 medical library directors in hospital and academic medical libraries were surveyed. The data was then compared to survey data from other compensation studies of the IT industry. RESULTS: There is a gap in compensation between medical library professionals and IT professionals performing similar functions using information technology. Technology-intense library jobs are compensated at higher levels than more traditional jobs. CONCLUSIONS: To compete with IT salaries, managers of medical library professionals will need to be ever more cognizant of the employment practices of IT professionals in nonmedical library disciplines. It is typically in the medical library's best interest to ensure that IT-related jobs, accountabilities, and capabilities of the medical library are known and understood by others, especially in the human resources and information technology staff departments.  相似文献   
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