881 resultados para knowing-what (pattern recognition) element of knowing-how knowledge
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Based on a plenary lecture presented at the Tenth ANZFSS meeting of Forensic science in Sydney (September 2010), this article identifies some of the difficulties arising from the confrontation of forensic science with the law : a science defined by its specialities rather its object (the trace) and through the eyes of the law rather than those of science. This situation has historical roots that are highlighted and potential solutions for the future lie in fundamental and cultural developments within forensic science itself.
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The spectral efficiency achievable with joint processing of pilot and data symbol observations is compared with that achievable through the conventional (separate) approach of first estimating the channel on the basis of the pilot symbols alone, and subsequently detecting the datasymbols. Studied on the basis of a mutual information lower bound, joint processing is found to provide a non-negligible advantage relative to separate processing, particularly for fast fading. It is shown that, regardless of the fading rate, only a very small number of pilot symbols (at most one per transmit antenna and per channel coherence interval) shouldbe transmitted if joint processing is allowed.
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The coreid Leptoglossus zonatus (Dallas, 1852) is commonly found in corn (Zea mays L.) fields in Brazil, and it has been observed flying and landing on objects or persons near these fields. During January, 1995, this behavior was studied in corn plantations. Results indicated that the bugs concentrated on objects (plastic cylinders traps) introduced into their habitat and that their number increased during the first 24 hs. However, as time passed (8 days), this possible territorial or recognition behavior gradually decreased, and tended to disappear.
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Background a nd A ims: D iscriminating irritable bowelsyndrome (IBS) from inflammatory bowel disease (IBD) can bea clinical c hallenge as s ymptoms c an overlap. We a nd othershave recently shown that fecal c alprotectin ( FC) is moreaccurate for d iscriminating IBS f rom IBD compared to C -reactive p rotein ( CRP) and b lood leukocytes. We a imed toassess which b iomarkers are used by g astroenterologists intheir daily practice for discriminating IBS from IBD.Methods: A q uestionnaire was sent to all board certifiedgastroenterologists in Switzerland in July 2010.Results: Response rate was 57% (153/270). Mean physician'sage was 50±9years, mean duration o f gastroenterologicpractice 1 4±8years, 52% of them were working in p rivatepractice a nd 48% in h ospitals. T he following biomarkers weredetermined for discriminating IBS from IBD: CRP 100%, FC79%, hematogram (red blood cells and leukocytes) 70%, ironstatus ( ferritin, t ransferrin s aturation) 59%, e rythrocytesedimentation rate 2.7%, protein electrophoresis 0.7%, andalpha-1 antitrypsin clearance 0.7%. There was a trend for usingFC more often in p rivate practice t han in h ospital ( P = 0.08).Eighty-nine percent of gastroenterologists considered FC to besuperior to CRP for discriminating IBS from IBD, 8 7% thoughtthat patient's compliance for fecal sampling is high, and 51%judged the fee of USD 60 for a FC test as appropriate.Conclusions: F C is widely used in c linical practice t odiscriminate IBS from IBD. In accordance with the scientificevidence, the majority of gastroenterologists consider FC to bemore accurate than CRP for discriminating IBS from IBD.
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An algorithm for computing correlation filters based on synthetic discriminant functions that can be displayed on current spatial light modulators is presented. The procedure is nondivergent, computationally feasible, and capable of producing multiple solutions, thus overcoming some of the pitfalls of previous methods.
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We report the study of the influence of optical aberrations in a joint-transform correlator: The wave aberration of the optical system is computed from data obtained by ray tracing. Three situations are explored: We consider the aberration only in the first diffraction stage (generation of power spectrum), then only in the second (transformation of the power spectrum into correlation), and finally in both stages simultaneously. The results show that the quality of the correlation is determined mostly by the aberrations of the first diffraction stage and that we can optimize the setup by moving the cameras along the optical axis to a suitable position. The good agreement between the predicted data and the experimental results shows that the method explains well the behavior of optical diffraction systems when aberrations are taken into account.
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Pseudomonas sp. strain B13 is a bacterium known to degrade chloroaromatic compounds. The properties to use 3- and 4-chlorocatechol are determined by a self-transferable DNA element, the clc element, which normally resides at two locations in the cell's chromosome. Here we report the complete nucleotide sequence of the clc element, demonstrating the unique catabolic properties while showing its relatedness to genomic islands and integrative and conjugative elements rather than to other known catabolic plasmids. As far as catabolic functions, the clc element harbored, in addition to the genes for chlorocatechol degradation, a complete functional operon for 2-aminophenol degradation and genes for a putative aromatic compound transport protein and for a multicomponent aromatic ring dioxygenase similar to anthranilate hydroxylase. The genes for catabolic functions were inducible under various conditions, suggesting a network of catabolic pathway induction. For about half of the open reading frames (ORFs) on the clc element, no clear functional prediction could be given, although some indications were found for functions that were similar to plasmid conjugation. The region in which these ORFs were situated displayed a high overall conservation of nucleotide sequence and gene order to genomic regions in other recently completed bacterial genomes or to other genomic islands. Most notably, except for two discrete regions, the clc element was almost 100% identical over the whole length to a chromosomal region in Burkholderia xenovorans LB400. This indicates the dynamic evolution of this type of element and the continued transition between elements with a more pathogenic character and those with catabolic properties.