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To identify susceptibility loci for meningioma, we conducted a genome-wide association study of 859 affected individuals (cases) and 704 controls with validation in two independent sample sets totaling 774 cases and 1,764 controls. We identified a new susceptibility locus for meningioma at 10p12.31 (MLLT10, rs11012732, odds ratio = 1.46, P(combined) = 1.88 × 10(-14)). This finding advances our understanding of the genetic basis of meningioma development.  相似文献   
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Counts of Double-crested Cormorants ( Phalacrocorax auritus ) were made at 13 reservoirs and lakes in southwestern Utah during 1989-91 to determine current abundance of that species. Food habits of cormorants were studied at three of the reservoirs in 1989. Data were also collected on trout abundance during standardized gill-netting to make comparisons between cormorant numbers and trout abundance. Cormorants were observed at all waters studied except one and were generally most numerous during the spring as they migrated through the area. Estimated cormorant abundance ranged from 0 to 34 bird-days per ha and was highest at the larger, lower-elevation reservoirs. Cormorants were summer residents at several of the larger reservoirs and nested successfully at Piute Reservoir. Trout accounted for 24-81% of the diet of cormorants, with Utah chubs constituting most of the remainder of the diet. Estimates of the annual consumption of fish by cormorants ranged from 0 to 15.8 kg per ha. The index of trout abundance was inversely related to cormorant abundance ( P < .01) at the waters studied. Cormorants apparently have increased in numbers and extended their range in southwestern Utah during the past decade. This change may be the result of factors that have led to similar changes throughout North America as well as some factors unique to Utah. Methods to mitigate the impact of predation by piscivorous birds of sportfisheries are discussed. The Utah Division of Wildlife Resources has initiated a new management plan at Minersville Reservoir that incorporates piscivorous birds into sportfish management at that reservoir.  相似文献   
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The Bonneville cutthroat trout ( Oncorhynchus clarki utah ; BCT) was once abundant throughout the Bonneville Basin. In southwestern Utah, however, only 3 local populations of the subspecies were known to exist in 1977, when conservation efforts to protect and replicate them began. By 1995 remnant populations were known in 6 streams, and replicate populations had been established in an additional 16. Populations of BCT in southwestern Utah streams were survey by electrofishing in 1994 and 1995 to describe the subspecies' status. Estimated densities of age-1 and older BCT ranged from 118 to 546 fish per km. Biomass estimates ranged from 8 to 64 kg per ha. Several age groups of BCT were collected at most locations. Six populations were classified as self-sustaining, 9 as expanding through natural recruitment, 6 as new, and 1 as hybridized. Overall status of BCT in southwestern Utah has improved since 1977, but conservation measures must continue to maintain a positive trend.  相似文献   
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Exposure of rare-earth films to hydrogen can induce a metal-insulator transition, accompanied by pronounced optical changes. This 'switchable mirror' effect has received considerable attention from theoretical, experimental and technological points of view. Most systems use polycrystalline films, but the synthesis of yttrium-based epitaxial switchable mirrors has also been reported. The latter form an extended self-organized ridge network during initial hydrogen loading, which results in the creation of micrometre-sized triangular domains. Here we observe homogeneous and essentially independent optical switching of individual domains in epitaxial switchable mirrors during hydrogen absorption. The optical switching is accompanied by topographical changes as the domains sequentially expand and contract; the ridges block lateral hydrogen diffusion and serve as a microscopic lubricant for the domain oscillations. We observe the correlated changes in topology and optical properties using in situ atomic force and optical microscopy. Single-domain phase switching is not observed in polycrystalline films, which are optically homogeneous. The ability to generate a tunable, dense pattern of switchable pixels is of technological relevance for solid-state displays based on switchable mirrors.  相似文献   
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大叶白麻叶化学成分的研究   总被引:1,自引:0,他引:1  
从大叶白麻[poacynumhendersonii(Hookf)woodson]叶中分得2个木脂素类化舍物,经理化常数测定和光谱分析,分别鉴定为(-)-丁香脂素[(-)-Syringaresino1]和( )-松脂素-4-O-β-D-葡萄糖甙[( )-Pinoresionol-4-0-β-D-glucopyranoside].  相似文献   
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Field surveys were conducted during 1997 and 1998 documenting the distribution and abundance of Colorado River cutthroat trout ( Oncorhynchus clarki pleuriticus ) in Escalante River tributaries. This documented occurrence of native trout in the Escalante River drainage of southern Utah represents an expansion of the known historic range of this subspecies as reported before the 1990s. We found 5 populations of native trout ranging in biomass from 3.0 to 104.2 kg ha -1 and occupying 13.2 km of stream of 130 km of estimated historic habitat. Current distribution and abundance of Colorado River cutthroat trout were compared to early introductions of nonnative trout stocked for sport fishing purposes. Native cutthroat trout have been displaced by nonnative cutthroat trout ( O. c. bouveri ), rainbow trout ( O. mykiss ), brook trout ( Salvelinus fontinalis ), and brown trout ( Salmo trutta ) except where they were isolated by physical or biological barriers. Displacement may have been more extensive except for the remoteness of the drainage and relatively recent introductions of nonnative trout. These conditions limited the overall amount of the drainage stocked, numbers of nonnative trout stocked, and time over which stocking occurred. Discoveries of native trout populations within the Escalante River drainage have allowed expanded conservation of this subspecies by adding new populations to what was known to exist and by increasing the known natural range of this fish.  相似文献   
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