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Extensive Database (extensive + database)
Selected AbstractsEnergetic cost of calling: general constraints and species-specific differencesJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 7 2010A. G. OPHIR Abstract The energetic cost of acoustic signalling varies tremendously among species. Understanding factors responsible for this heterogeneity is important for understanding the costs and benefits of signalling. Here, we present a general model, based on well-established principles of bioenergetics, which predicts the energetic cost of call production across species. We test model predictions using an extensive database of resting and calling metabolic rates of insects, amphibians and birds. Results are largely supportive of model predictions. Calling metabolic rates scale predictably with body mass and temperature such that calling and resting metabolic rates are directly proportional to each other. The cost of acoustic signalling is ,8 times higher than resting metabolic rate in ectotherms, and ,2 times higher in birds. Differences in the increase in metabolic rate during calling are explained by the relative size of species' sound-producing muscles. Combined with published work, we quantify call efficiency and discuss model implications. [source] Talking past each other: Journalists, readers and local newspaper reporting of general election campaigns in the UKJOURNAL OF PUBLIC AFFAIRS, Issue 4 2004Bob Franklin Abstract Drawing on an extensive database of local press reporting of the last four general elections (1987, 1992, 1997 and 2001), as well as contemporary interviews with journalists and editors, this paper argues that local press coverage of the constituency campaign has changed markedly since 1987, and in ways which may contribute to diminishing voter interest and participation in elections. Significantly, journalists do not perceive themselves as the ,cause' of voter apathy, but their efforts to ,lighten up' election coverage and report local election issues, contrast starkly with readers' preference for more serious reporting of the national agenda. Journalists and readers appear to be talking past each other in the pages of the local press. Copyright © 2004 Henry Stewart Publications [source] A population-based birth defects surveillance system in the People's Republic of ChinaPAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 3 2003Song Li Summary We describe a unique birth defects surveillance system in the People's Republic of China. The system was instituted in March 1992 as a component of an evaluation of the effectiveness of a public health campaign using periconceptional folic acid supplementation to prevent neural tube defects, and currently surveys birth cohorts of , 150 000 infants per year. Local health care providers collect information in the form of detailed written descriptions and photographs of affected infants. The system allows for detection of birth defects at the local level with later definitive classification and coding; however, information is limited to structural anomalies that are visible on physical examination. This birth defects surveillance system provides an extensive database of infants with major and minor external structural anomalies, including the unique feature of a photographic record for most cases. These data can be used for aetiological studies, descriptive epidemiology and identification of unusual trends. [source] Prognostic significance of RET and NTRK1 rearrangements in sporadic papillary thyroid carcinomaBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 9 2000T. J. Musholt Background The genetic background of papillary thyroid carcinoma (PTC) has been elucidated by the identification of somatic translocations of the tyrosine kinases RET and NTRK1. Expression of RET/PTC chimeras has been demonstrated in 10,25 per cent of sporadic PTCs while rearrangements of NTRK1 were detected less frequently. Based upon the limited data available, some investigators have hypothesized that RET/PTC activation is preferentially associated with slow growing tumours of low malignancy in elderly patients, while other studies support the contrary. Methods Tumour tissues from 115 patients with sporadic PTC were harvested at operation and snap frozen. Following RNA extraction, expression analysis of the RET proto-oncogene as well as the NTRK1 gene was performed by multiplex reverse transcriptase,polymerase chain reaction. Samples with suspected rearrangements of the genes were further analysed for expression of the hybrid messenger RNAs RET/PTC1 to RET/PTC4, and for known NTRK1 chimeras. Clinical data of all patients were documented in an extensive database of thyroid carcinomas maintained by this research group. Results Twenty-one (18 per cent) of 115 tumour samples revealed somatic rearrangements of RET while translocations of the NTRK1 gene were demonstrated in 2 per cent of all samples analysed to date. The mean age of all patients was 52 (range 14,86, median 54) years and that of patients positive for RET rearrangements was 49 (range 14,82, median 49) years. Nine of 21 RET -rearranged tumours showed aggressive behaviour with locally invasive tumour growth and infiltration of adjacent structures such as muscles, vessels and trachea. Tumour samples without detectable RET translocations were associated with organ-exceeding tumour growth in only 20 per cent of cases. Conclusion These data represent one of the most comprehensive studies on gene translocations and their clinical significance in PTC. In accordance with international publications, an incidence of 2 per cent of NTRK1 rearrangements and 18 per cent of RET translocations is reported, which is in contrast to other national reports of low rearrangement rates. Somatic translocations were associated with tumours demonstrating aggressive behaviour in almost half of patients with PTC in all age groups, indicating a prognostic role of oncogenic RET/PTC activation. © 2000 British Journal of Surgery Society Ltd [source] Effective use of fluorides for the prevention of dental caries in the 21st century: the WHO approachCOMMUNITY DENTISTRY AND ORAL EPIDEMIOLOGY, Issue 5 2004Poul Erik Petersen Abstract , Despite great improvements in the oral health of populations across the world, problems still persist particularly among poor and disadvantaged groups in both developed and developing countries. According to the World Oral Health Report 2003, dental caries remains a major public health problem in most industrialized countries, affecting 60,90% of schoolchildren and the vast majority of adults. Although it appears that dental caries is less common and less severe in developing countries of Africa, it is anticipated that the incidence of caries will increase in several countries of that continent, due to changing living conditions and dietary habits, and inadequate exposure to fluorides. Research on the oral health effects of fluoride started around 100 years ago; the focus has been on the link between water and fluorides and dental caries and fluorosis, topical fluoride applications, fluoride toothpastes, and salt and milk fluoridation. Most recently, efforts have been made to summarize the extensive database through systematic reviews. Such reviews concluded that water fluoridation and use of fluoride toothpastes and mouthrinses significantly reduce the prevalence of dental caries. WHO recommends for public health that every effort must be made to develop affordable fluoridated toothpastes for use in developing countries. Water fluoridation, where technically feasible and culturally acceptable, has substantial advantages in public health; alternatively, fluoridation of salt and milk fluoridation schemes may be considered for prevention of dental caries. [source] | ||||||||||