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71.
Working Graphs     
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72.
An investigation has been undertaken at St Andrew’s church, Walpole St Andrew, Norfolk, to establish the underlying causes of the observed stone decay to the upper parts of the six stone piers. The stone decay was first recorded in the early 1930s. The salt-contaminated masonry within the church has been shown to undergo severe salt decay during the summer, with little damage occurring over the winter months. The south aisle piers have been shown to decay 2.5 times faster than the north aisle piers. Although crystallization–hydration cycles have been identified, the rate of decay is at its greatest when the cycling is relatively infrequent. This was not the expected trend. Furthermore, it has been shown that during extended periods where the ambient relative humidity is less than 75%, the rate of decay reaches a maximum. It is the length of this ‘drying’ period that apparently has the greatest influence on the rate of decay and could explain the significant difference in the rate of decay between the south and north aisle piers. The results have serious implications for passive conservation, where it is often recommended to lower the ambient relative humidity to well below the equilibrium relative humidity of the salt contaminant, to avoid crystallization–hydration cycles. Since, at the time of building, the church was situated on the coast, it is possible that the sodium chloride contamination occurred during the building process (1440–1520), particularly since the area was prone to sea-flooding at this time. Alternatively, the salt could have been applied as a treatment during the general restoration of 1897. Whatever the source of the salt, it seems likely that the ambient environment was changed by the insertion of a sealed floor in 1897, which could account for the onset of the salt decay.  相似文献   
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The research discussed in the present paper, set out to find how a sample of Singaporean adolescents perceived and managed different sources of stress. The sample totalled 212 pre-university students with equal numbers of boys and girls, and a mean age of 17 years 5 months. The students attended a number of junior colleges in the republic, with the sample ethnicity reflecting national proportions. Measures of stress included Behaviour Profile, Life Events, School Stress Factors, Home-School Stress Conditions and Stress Symptoms. All measures were administered as questionnaires.

The results showed that several features of Type A behaviour emerged and that school examinations, job aspirations, school work and homework were the principal stressors. Fear of the unexpected, exhaustion and lack of concentration were the most quoted stress symptoms. Science students appeared to be more stressed than arts students.

Among the main management strategies employed by these adolescents at home, were listening to music, reading and exercise, while stress in school was managed through self control, self-sufficiency and sharing problems with peers. In the main, most students seemed to be able to cope by adapting to stressful situations as they arose at a particular time.

Some of the more important implications of the above findings are discussed in the context of schooling in Singapore and in the wider context of society.  相似文献   

77.
Computers are integral to medical practice, education, and research. While medical students learn computer skills during their training, many practicing physicians do not have the same computer experience. To familiarize this group with the exciting developments in medical informatics, the Himmelfarb Health Sciences Library and Department of Computer Medicine at the George Washington University Medical Center organized a workshop "Introducing Your Office Computer!" for attending physicians. The workshop featured a short lecture/video presentation on computer applications in medicine followed by a "computer fair" of five computer applications. Eleven physicians attended the workshop. Feedback was very positive; many called later to request more detailed instructions on using the programs demonstrated. It was a valuable experience for the staff, and new bridges were built between departments and clients.  相似文献   
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The National Library of Medicine has had an enormous impact on health information services all over the world. Although NLM is primarily a national institution, it has become an important international resource by responding to requests from the international community. NLM has been influential in three major ways. First, NLM has provided a model for other national and regional health information services. Second, it has been a catalyst, in that MEDLARS and other services it provides formed the nucleus of many regional networks. NLM helped such networks get started by giving advice on how to set up services and build collections and by "training the trainers" on the MEDLARS system. Third, NLM has supported national and regional operations by providing the additional training and materials needed for day-to-day service.  相似文献   
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Policies for responding to allegations of fraud in research   总被引:1,自引:0,他引:1  
Greene PJ  Durch JS  Horwitz W  Hooper VS 《Minerva》1985,23(2):203-215
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