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131.
We have identified nonsense mutations in the gene CDSN (encoding corneodesmosin) in three families suffering from hypotrichosis simplex of the scalp (HSS; OMIM 146520). CDSN, a glycoprotein expressed in the epidermis and inner root sheath (IRS) of hair follicles, is a keratinocyte adhesion molecule. Truncated CDSN aggregates were detected in the superficial dermis and at the periphery of hair follicles. Our findings suggest that CDSN is important in normal scalp hair physiology.  相似文献   
132.
Herbicides including Agent Orange were sprayed by United States forces for military purposes during the Vietnam War (1961-1971) at a rate more than an order of magnitude greater than for similar domestic weed control. In 1974, the US National Academy of Sciences published estimates of the extent and distribution of herbicides sprayed. Here we present revised estimates, developed using more-complete data. The spray inventory is expanded by more than seven million litres, in particular with heavily dioxin-contaminated herbicides. Estimates for the amount of dioxin sprayed are almost doubled. Hamlet census data reveal that millions of Vietnamese were likely to have been sprayed upon directly. Our identification of specific military herbicide targets has led to a more coherent understanding of spraying. Common errors in earlier interpretations of the spray data are also discussed.  相似文献   
133.
Company bankruptcies cost billions of dollars in losses to banks each year. Thus credit risk prediction is a critical part of a bank's loan approval decision process. Traditional financial models for credit risk prediction are no longer adequate for describing today's complex relationship between the financial health and potential bankruptcy of a company. In this work, a multiple classifier system (embedded in a multiple intelligent agent system) is proposed to predict the financial health of a company. In our model, each individual agent (classifier) makes a prediction on the likelihood of credit risk based on only partial information of the company. Each of the agents is an expert, but has limited knowledge (represented by features) about the company. The decisions of all agents are combined together to form a final credit risk prediction. Experiments show that our model out-performs other existing methods using the benchmarking Compustat American Corporations dataset.  相似文献   
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135.
The rate and distribution of deformation along the Qilian Mountain, on the northeastern Tibetan Plateau, is needed to understand the evolution of high topography associated with the plateau. Recently, a number of empirical studies have provided support for the contention, common to most models of fluvial incision, that rock uplift rate exerts a first-order control on the gradient of longitudinal river profiles. Along the northern Qilian Mountain, this method is used to extract information about the spatial patterns of differential rock uplift. Analysis of the longitudinal profiles of bedrock channels reveals systematic differences in the channel steepness index along the trend of the frontal ranges. Local comparisons of channel steepness reveal that lithology and precipitation have limited influence on channel steepness. Similarly, there is little evidence suggesting that channel steepness is influenced by differences in the sediment loads. We argue that the distribution of channel steepness in the Qilian Mountain is mostly the result of differential rates of rock uplift. Thus, channel steepness indices reveal a lower rock uplift rate in the eastern portion of the Qilian Mountain and a higher rate in the middle and west. The highest rates appear to occur in the middle-west portions of the range, just to the west of the Yumu Shan.  相似文献   
136.
Benthic macroinvertebrates from four habitat types (river channel, ephemeral side channel, river backwater, and seasonally inundated wetland) were examined from the Green River at the Ouray National Wildlife Refuge, Uintah County, UT, June-August 1991. For major taxa (Nematoda, Oligochaeta, Diptera: Ceratopogonidea, and Chironomidae) were quantified. Chuster analysis of densities showed that habitat types with comparable flow conditions were the most similar. Highest to lowest overall benthic invertebrate densities of the four habitats were as follows: ephemeral side channel, river backwater, seasonally inundated wetland, and river channel. Nematodes were the most abundant taxon in all habitat types and sample dates except the August sample of the river channel and river backwater and the July sample of the seasonally inundated wetland.  相似文献   
137.
138.
Thirty - nine Utah streams were sampled for cutthroat trout. Of these, 31 contain cutthroat or cutthroat / rainbow hybrid populations. By using starch gel electrophoresis, these populations were segregated into three groups. One group consisted predominately of fish from the Sevier River (of the Bonneville Basin) and Colorado drainages. A second was primarily populations from the Bear River Drainage (Bonneville Basin) as well as some scattered populations along the Wasatch Front (Bonneville Basin). The third consisted of Wasatch Front populations and populations that have hybridized with rainbow trout. Since different subspecies of cutthroat trout are native to the Colorado and Bonneville drainages, one would expect the populations from within the Bonneville Basin to be more similar to one another and less similar to the Colorado River populations. That this did not occur raises questions concerning the evolutionary relationships of the subspecies and the populations. It is clear that at least a northern (Bear River) and southern (Sevier River) form of the Bonneville cutthroat exists. The Wasatch Front may represent an intermediate zone where these two forms intergrade.      相似文献   
139.
A standard approach to the combination of probabilistic opinions involves taking a weighted linear average of the individuals distributions. This paper reviews some of the possible interpretations that have been proposed for these weights in the literature on expert use. Several paradigms for selecting weights are also considered. Special attention is devoted to the Bayesian mechanism used for updating expert weights in the face of new information. An asymptotic result is proved which highlights the importance of choosing the initial weights carefully.  相似文献   
140.
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