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981.
982.
In recent years it has been estimated that from 30 percent to 50 percent of the medical complaints brought to the family or general practice physician are functional in nature and may be psychosocial in origin (Harmon, Masuda & Holmes 1970). While chemotherapy may be appropriate for the patient with acute situational anxiety and psychiatric consultation may be appropriate for the severely neurotic or psychotic patient, the family practice physician has few remedies for the patient with chronic aches and pains, housewife syndrome, middle-age depression, businessman's fatigue, and a host of other quasimedical complaints.  相似文献   
983.
984.
This paper describes the philosophy of ELDERHOSTEL, an organization which began in 1975 with five colleges in New Hampshire offering a total of 15 weeks of higher education programs for persons 60 years of age and older. By the summer of 1979, more than 500 weeks of ELDERHOSTEL programs were being offered at 235 college and university campuses in 37 states.Martin P. Knowlton is Director of the New England Center for Social Invention and a founder of ELDERHOSTEL.  相似文献   
985.
986.
987.
According to user innovation literature, users can create important innovations and the novel functionalities embedded in those user innovations often become the sources of subsequent innovations by both other users and manufacturers. However, manufacturers are often hesitant in commercializing an innovation created by a single user due to the uncertainty around the market demands. We propose that such hesitancy will decrease when an increasing number of other users source knowledge elements from the focal user innovation and reproduce the novel functionality. Once the focal user innovation is commercialized by manufacturers, other users can purchase the novel functionality from the market rather than reproducing it in house. We propose that users capable of drawing on innovation resources are more likely to maintain in-house reproduction of the focal user innovation than users low on innovation resources. By using the Vector Autoregressive (VAR) model and Impulse Response Function (IRF) analysis method, we analyze knowledge sourcing activities from financial software patents data, and the findings provide empirical supports for our propositions.  相似文献   
988.
In this paper, a decision model is presented for the sales of software product to determine the profit and marketing policy under the influence of promotional efforts. The paper focuses on dependence of the optimal profit on the promotional efforts when there is diffusion effect of demand on the sales function. An elaborate optimization policy considering the dynamic nature of production cost function is proposed and numerical example is illustrated. The paper also studies the behavior of the future profit and its impact on profit maximization model by considering the constant price during the entire planning horizon. The experimental results greatly help us to identify the contributions of each selected parameter and its weight. Some conclusions, limitations of this study and future direction are also discussed.  相似文献   
989.
An individual's level of physical activity influences their risk of infection, most likely by affecting immune function. Regular moderate exercise reduces the risk of infection compared with a sedentary lifestyle, but very prolonged bouts of exercise and periods of intensified training are associated with an increased risk of infection. There are several lifestyle, nutritional, and training strategies that can be adopted to limit the extent of exercise-induced immunodepression and minimize the risk of infection. This expert statement provides a background summarizing the evidence together with extensive conclusions and practical guidelines.  相似文献   
990.
The field hockey hit is an important but poorly understood stroke. In this study, we investigated the planarity of the stickface motion during the downswing to better characterize the kinematics and to assess the suitability of planar pendulum models for simulating the hit. Thirteen experienced female field hockey players were filmed executing hits with a single approach step, and the kinematics of the centre of the stickface were measured. A method was developed for identifying how far back from impact the stickface motion was planar. Orthogonal regression was used to fit least-squares planes to the stickface path during sections of the downswing of varying length, with each section ending at impact. A section was considered planar if the root mean square residual between the stickface path and the fitted plane was less than 0.25% of the distance travelled by the stickface during that period. On average, the stickface motion was planar for the last 83 ± 12% of its downswing path, with the length of the planar section ranging from 1.85 m to 2.70 m. The suitability of a planar model for the stickface motion was supported, but further investigation of the stick and arm kinematics is warranted.  相似文献   
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