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Sole Determinant (sole + determinant)
Selected AbstractsClimate, climate change and range boundariesDIVERSITY AND DISTRIBUTIONS, Issue 3 2010Chris D. Thomas Abstract Aim, A major issue in ecology, biogeography, conservation biology and invasion biology is the extent to which climate, and hence climate change, contributes to the positions of species' range boundaries. Thirty years of rapid climate warming provides an excellent opportunity to test the hypothesis that climate acts as a major constraint on range boundaries, treating anthropogenic climate change as a large-scale experiment. Location, UK and global data, and literature. Methods, This article analyses the frequencies with which species have responded to climate change by shifting their range boundaries. It does not consider abundance or other changes. Results, For the majority of species, boundaries shifted in a direction that is concordant with being a response to climate change; 84% of all species have expanded in a polewards direction as the climate has warmed (for the best data available), which represents an excess of 68% of species after taking account of the fact that some species may shift in this direction for non-climatic reasons. Other data sets also show an excess of animal range boundaries expanding in the expected direction. Main conclusions, Climate is likely to contribute to the majority of terrestrial and freshwater range boundaries. This generalization excludes species that are endemic to specific islands, lakes, rivers and geological outcrops, although these local endemics are not immune from the effects of climate change. The observed shifts associated with recent climate change are likely to have been brought about through both direct and indirect (changes to species' interactions) effects of climate; indirect effects are discussed in relation to laboratory experiments and invasive species. Recent observations of range boundary shifts are consistent with the hypothesis that climate contributes to, but is not the sole determinant of, the position of the range boundaries of the majority of terrestrial animal species. [source] Dietary accumulation of perfluorinated acids in juvenile rainbow trout (Oncorhynchus mykiss)ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 1 2003Jonathan W. Martin Abstract Perfluorinated acids (PFAs) recently have emerged as persistent global contaminants after their detection in wildlife and humans from various geographic locations. The highest concentrations of perfluorooctane sulfonate are characteristically observed in high trophic level organisms, indicating that PFAs may have a significant bioaccumulation potential. To examine this phenomenon quantitatively, we exposed juvenile rainbow trout (Oncorhynchus mykiss) simultaneously to a homologous series of perfluoroalkyl carboxylates and sulfonates for 34 d in the diet, followed by a 41-d depuration period. Carcass and liver concentrations were determined by using liquid chromatography-tandem mass spectrometry, and kinetic rates were calculated to determine compound-specific bioaccumulation parameters. Depuration rate constants ranged from 0.02 to 0.23/d, and decreased as the length of the fluorinated chain increased. Assimilation efficiency was greater than 50% for all test compounds, indicating efficient absorption from food. Bioaccumulation factors (BAFs) ranged from 0.038 to 1.0 and increased with length of the perfluorinated chain; however, BAFs were not statistically greater than 1 for any PFA. Sulfonates bioaccumulated to a greater extent than carboxylates of equivalent perfluoroalkyl chain length, indicating that hydrophobicity is not the sole determinant of PFA accumulation potential and that the acid function must be considered. Dietary exposure will not result in biomagnification of PFAs in juvenile trout, but extrapolation of these bioaccumulation parameters to larger fish and homeothermic organisms should not be performed. [source] 5.2 Ethics, equity and global responsibilities in oral health and diseaseEUROPEAN JOURNAL OF DENTAL EDUCATION, Issue 2002Martin Hobdell The charge of this Section is ethics and global responsibilities in oral health and disease. Oral health is determined by the same factors as those for general health. To a limited extent, the level of oral health care and dental education. The philosophy and organization of the health care system and dental education, therefore, are key determinants of oral health. Dental education has expanded in many countries where there has been an increase in wealth. Unfortunately, there has been no concomitant increase in the number of dental educators. This is a problem throughout the world. This present situation raises certain ethical issues with regard to professional responsibilities. It also raises some important questions for dental education. This Section has chosen to focus its efforts on examining two issues: , ,What can be done within dental schools? , ,What can be done external to dental schools , either individually or collectively? The best practices identified are more akin to goals, as it is recognized that, in a world in which there are enormous variations in economic, environmental, social, and cultural features, a single uniform set of practices is impracticable. The central core value identified is the realization by students, and faculty/teaching staff of the quest of life-long learning against a background of the social and ethical responsibilities of health professionals. The conclusion of the group is that biology is not the sole determinant of health. Understanding the role of social, economic, environmental and other factors in determining health status is critical if greater equity in dental education and care are to be achieved. [source] Primary biliary cirrhosis in Singapore: Evaluation of demography, prognostic factors and natural course in a multi-ethnic populationJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 4 2008Reuben-Km Wong Abstract Background and Aim:, Primary biliary cirrhosis (PBC) is infrequent in Asians. Among Asian patients with PBC, information on natural course is scarce. The aim of this study was to study the clinical course and prognosticators among Asians with PBC. Methods:, During 1990,2005, patients diagnosed with PBC at the National University Hospital, Singapore, constituted the retrospective cohort. Their demographic characteristics were evaluated. To evaluate the prognostic factors and natural course, two outcome measures were assessed: hepatic decompensation and death or liver transplant. Multivariate analysis was undertaken to identify factors associated with hepatic decompensation and terminal event (death or liver transplantation). Results:, Thirty-four PBC patients aged 56.8 ± 1.8 years (mean ± SEM) of whom 32 (94%) were women were included. Thirty-two (94%) of them were of Chinese origin. At presentation, 18 (53%) were symptomatic in the form of jaundice (n = 9, 26.5%), pruritus (n = 6, 17.6%) and fatigue (n = 5, 14.7%). During 4.80 ± 0.7 (range 0.02,15.03) years follow up, 6/16 (37.5%) asymptomatic patients developed symptoms. After 5 years, 17.6% (n = 6) and 8.8% (n = 3) had hepatic decompensation and terminal event, respectively. Sicca syndrome was present in 26% (n = 9) of patients. Multivariate analysis revealed that serum bilirubin level at presentation was the sole determinant of decompensation. Rate of change of laboratory indices did not predict either event. Conclusion:, In Singapore, Chinese women constitute most of the PBC patients. Elevated serum bilirubin level at presentation was the sole predictive marker associated with dismal outcome. [source] CYP2C19*2 polymorphism is not the sole determinant of the response to clopidogrel: implications for its monitoringJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 10 2009B. ALEIL [source] Mutations of the epidermal growth factor receptor gene and related genes as determinants of epidermal growth factor receptor tyrosine kinase inhibitors sensitivity in lung cancerCANCER SCIENCE, Issue 12 2007Tetsuya Mitsudomi Recent discovery of mutations in the tyrosine kinase domain of the epidermal growth factor receptor (EGFR) gene in lung adenocarcinoma greatly stimulated biomarker research on predictive factors for EGFR tyrosine kinase inhibitors (TKI), such as gefitinib and erlotinib. Although patients with activating mutations of the EGFR generally respond to EGFR TKIs very well, it is natural to assume that there is no sole determinant, considering great complexity and redundancy of the EGFR pathway. Subsequently, roles of different types of EGFR mutations or mutations of genes that are members of the EGFR pathway such as KRAS and HER2 have been evaluated. In this review, we summarize the recent findings about how mutations of the EGFR and related genes affect sensitivity to EFGR-TKIs. We also discuss molecular mechanisms of acquired resistance to EGFR-TKIs that is almost inevitable in EGFR-TKI therapy. The door for genotype-based treatment of lung cancer is beginning to open, and through these efforts, it will be possible to slow the progression of lung cancer and eventually, to decrease mortality from lung cancer. (Cancer Sci 2007; 98: 1817,1824) [source] | |||||||||||||