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Scientific Grounds (scientific + ground)
Selected AbstractsA portrait of Aristotle as an anatomist: Historical articleCLINICAL ANATOMY, Issue 5 2007Enrico Crivellato Abstract Aristotle is principally known as a theoretical philosopher and logician but he was also an eminent natural scientist. In particular, he should be considered probably the first anatomist in the modern sense of this term and the originator of anatomy as a special branch of knowledge. Although it seems certain that he did not perform dissections of human adult cadavers, he examined human fetal material and, above all, made systematic analysis of animal bodies. His contribution to comparative anatomy, as well as to human anatomy, was enormous. He founded the anatomical discipline on precise descriptive and scientific ground. He also coined a series of technical terms, which are still in use in the modern nomenclature. His observational skill was astounding. Although many of his physiological concepts turned out to be wrong, still his structural description of organs and body parts was often first-rank. The present study will chiefly focus on Aristotle's anatomical work and will provide only essential mention of his complex physiological and philosophical doctrine. The main purpose of this article is indeed to offer to today's anatomists a systematic account of the extraordinary achievements of this great pioneer of our discipline. Clin. Anat. 20:477,485, 2007. © 2006 Wiley-Liss, Inc. [source] The carcinogenicity of smegma: debunking a mythJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 9 2006RS Van Howe Abstract Background, Smegma is widely believed to cause penile, cervical and prostate cancer. This nearly ubiquitous myth continues to permeate the medical literature despite a lack of valid supportive evidence. Methods, A historical perspective of medical ideas pertaining to smegma is provided, and the original studies in both animals and humans are reanalysed using the appropriate statistical methods. Results, Evidence supporting the role of smegma as a carcinogen is found wanting. Conclusions, Assertions that smegma is carcinogenic cannot be justified on scientific grounds. [source] Authenticating the recovery location of meteorites: The case of CastenasoMETEORITICS & PLANETARY SCIENCE, Issue 3 2007Luigi Folco Using the hypothesis that Castenaso was instead a hot-desert meteorite, we conducted a comparative mineralogical and geochemical study of major weathering effects on European and Saharan ordinary chondrites as potential markers of the environment where Castenaso resided during its terrestrial lifetime. Inductively coupled plasma-mass spectrometry (ICP-MS) data reveals that Castenaso is significantly enriched in Sr, Ba, Tl, and U, and suggests geochemical alteration in a hot-desert environment. The alteration is minor: Castenaso is not coated by desert varnish and does not show significant light rare earth element (LREE) enrichment or loss of Ni and Co. The apparent contrast in size, morphology, and composition between the soil particles filling the external fractures of Castenaso and those from the bank of the Idice Stream observed under the scanning electron microscope (SEM) suggests that Castenaso did not reside at the reported find location. Abraded quartz grains (up to 1 mm in size) in Castenaso are undoubtedly from a hot-desert eolian environment: they are well-rounded and show external surfaces characterized by the presence of dish-shaped concavities and upturned silica plates that have been subject to solution-precipitation and subsequent smoothing. We therefore conclude that Castenaso is one of the many hot-desert ordinary chondrite finds, probably from the Sahara, that is currently available on the market. This forensic work provides the scientific grounds for changing the name of this meteorite. [source] Methodology for drawing up a Red List of threatened freshwater fish in FranceAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 2 2002P. Keith Abstract 1.In 1995, the IUCN implemented new definitions to be used when drawing up red lists. However, in addition to being imprecise for fish species, these remain difficult to apply. 2.This paper describes a more exhaustive method under the IUCN (1995) definitions based on six quantitative and qualitative criteria where scientific data are given the greatest possible weight, as compared with ,expert opinion'. This dual system makes it possible both to allocate an IUCN category to each species, and to rank each species within a particular category according to given scores, so that priorities can be determined. 3.The new Red List for French Freshwater Fish drawn up with this method contains 27 species, or 54% of the French native fauna. Three species are extinct (EX), four are critically endangered (CR), two are endangered (EN), 14 are vulnerable (VU), and four are at lower risk (LR). 4.Based on sounder scientific grounds, this list modifies and replaces the one drawn up in 1992. In effect, it makes it easier to argue for the presence of one species in one category rather than in another. Copyright © 2002 John Wiley & Sons, Ltd. [source] Does alpine grazing reduce blazing?AUSTRAL ECOLOGY, Issue 8 2006A landscape test of a widely-held hypothesis Abstract ,Alpine grazing reduces blazing' is a widely and strongly held view concerning the effects of livestock grazing on fuels, and therefore fire behaviour and impact, in Australia's high country landscapes. As a test of this hypothesis, we examined the patterns of burning across the alpine (treeless) landscapes of the Bogong High Plains in Victoria, following the extensive fires of January 2003. Data were collected from multiple transects, each 3,5 km long, with survey points located randomly at either 50, 200 or 500 m intervals. The transects traversed the major regions of the Bogong High Plains, both grazed and ungrazed. At each point, we recorded whether the point was burnt or unburnt, the vegetation type (closed-heath, open-heath, grassland or herbfield), the estimated prefire shrub cover, slope, aspect, and a GPS location. At burnt heathland sites, we recorded the minimum twig diameter (an a posteriori measure of fire severity) in a sample of common shrubs. In total, there were 108 km of transect lines, 419 survey points and 4050 twig measurements, with sample points equally distributed across grazed and ungrazed country. The occurrence of fire (i.e. burnt or unburnt) in grazed and ungrazed areas was analysed by logistic regression; the variation in twig diameters by anova. Approximately half of all points were burnt. There was no statistically significant difference between grazed and ungrazed areas in the proportion of points burnt. Fire occurrence was determined primarily by vegetation type, with the proportion burnt being 0.87 for closed-heath, 0.59 for open-heath, and 0.13 for grassland and all snow-patch herbfield points unburnt. In both closed-heath and open-heath, grazing did not significantly lower the severity of fire, as measured by the diameter of burnt twigs. We interpret the lack of a grazing effect in terms of shrub dynamics (little or no grazing effect on long-term cover of taller shrubs), diet and behaviour of cattle (herbs and dwarf shrubs eaten; tall shrubs not eaten and closed-heath vegetation generally avoided), and fuel flammability (shrubs more flammable than grass). Whatever effects livestock grazing may have on vegetation cover, and therefore fuels in alpine landscapes, they are likely to be highly localized, with such effects unlikely to translate into landscape-scale reduction of fire occurrence or severity. The use of livestock grazing in Australian alpine environments as a fire abatement practice is not justified on scientific grounds. [source] | ||||||||||