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231.
Reported are 105 species of Scolytidae (Coleoptera) from Idaho. About one-third of these are rarely collected, of which 22 species are known from a single locality each. Twelve species reported from Idaho for the first time are: Carphoborus carri Swaine, C. sansoni Swaine, Phloeosinus hoferi Blackman, Conophthorus monophyllae Hopkins, Dryocoetes betulae Hopkins, Ips confuses (LeConte), Pityophthorus absonus Blackman, P. aquilus Blackman , P. blandus Blackman, P. deletus LeConte, P. sculptor Blackman, and Xyleborinus saxeseni (Ratzeburg). Significant extensions of the known distributions in Idaho are reported for seven other scolytids; Alniphagus aspericollis (LeConte), Dendroctonus murrayanae Hopkins, Phloeotribus lecontei Schedl, Procryphalus mucronatus (LeConte), Trypophloeus populi Hopkins, Xyleborus dispar (Fabricius), and X. intrusus Blandford. Xyleborus dispar especially needs study in anticipation that it may become increasingly important in Idaho fruit trees and other woody plants including ornamentals and shade trees.  相似文献   
232.
The parasitic wasp Mymaromella pala Huber and Gibson (Hymenoptera: Mymarommatidae) was collected at 4 sites within a canyon reach of the Kootenai River in Lincoln County, Montana. This minute species has only recently been described, but it appears to have a large distribution throughout the United States and to be associated with upland and riparian forests. La avispa parasitaria Mymaromella pala Huber y Gibson (Hymenoptera: Mymarommatidae) se recolectó en cuatro sitios a lo largo de un cañón del Río Kootenai en Lincoln Co., MT. Hace poco que se describió esta especie diminuta, pero parece tener una distribución extensa en los EE.UU. y estar asociada con bosques altos y ribereños.  相似文献   
233.
The Plumbeous Vireo ( Vireo plumbeus ) is a poorly studied songbird species that breeds within the interior western United States and Mexico. We studied the breeding behavior of Plumbeous Vireos within pinyon-juniper habitats in northeastern New Mexico in 1996 and 1997. Over both years we located and monitored 40 nests and conducted behavioral observations throughout the nesting cycle. From these observations we described and compared basic behavioral traits of male and female vireos during their nest-building, egg-laying, incubation, and nestling stages, and their response to potential predators near the nest. Male vireos displayed potential nest sites to females, but the females selected the site to be used and built most of the nest. Vireos often did not initiate egg-laying until 2-3 d after nest completion. The female tended to incubate eggs and brood nestlings more than the male, but both parents contributed equally in provisioning the young. Brown-headed Cowbirds ( Molothrus ater ) parasitized 77% of nests in 1996, 63% in 1997, and parasitism was the primary cause of nest failure in this population. The conspicuousness of vireos around the nest, particularly during the nest-building stage, may contribute to high parasitism levels. Vireo aggression near the nest may also act as a cue to help cowbirds locate nests.  相似文献   
234.
Three condition models for wintering Northern Pintails ( Anas acuta ) were tested for their ability to predict fat mass, logarithm of fat mass, or a condition index (CI) incorporating fat mass. Equations generated to predict fat mass and the logarithm of fat mass accounted for more than 69% of the variation in these dependent variables. Log transformations of body mass, wing length, and total length explained at least 60% of the variation in CI. All models performed better on an independent data set. Mean prediction error was minimal (≤8% of measured variables) and negative for all models. Regression models apply to live and dead pintails and thus represent tools that have utility in a wide variety of studies on pintail condition.  相似文献   
235.
236.
Using variants from the 1000 Genomes Project pilot European CEU dataset and data from additional resequencing studies, we densely genotyped 183 non-HLA risk loci previously associated with immune-mediated diseases in 12,041 individuals with celiac disease (cases) and 12,228 controls. We identified 13 new celiac disease risk loci reaching genome-wide significance, bringing the number of known loci (including the HLA locus) to 40. We found multiple independent association signals at over one-third of these loci, a finding that is attributable to a combination of common, low-frequency and rare genetic variants. Compared to previously available data such as those from HapMap3, our dense genotyping in a large sample collection provided a higher resolution of the pattern of linkage disequilibrium and suggested localization of many signals to finer scale regions. In particular, 29 of the 54 fine-mapped signals seemed to be localized to single genes and, in some instances, to gene regulatory elements. Altogether, we define the complex genetic architecture of the risk regions of and refine the risk signals for celiac disease, providing the next step toward uncovering the causal mechanisms of the disease.  相似文献   
237.
238.
The Alzheimer Disease Genetics Consortium (ADGC) performed a genome-wide association study of late-onset Alzheimer disease using a three-stage design consisting of a discovery stage (stage 1) and two replication stages (stages 2 and 3). Both joint analysis and meta-analysis approaches were used. We obtained genome-wide significant results at MS4A4A (rs4938933; stages 1 and 2, meta-analysis P (P(M)) = 1.7 × 10(-9), joint analysis P (P(J)) = 1.7 × 10(-9); stages 1, 2 and 3, P(M) = 8.2 × 10(-12)), CD2AP (rs9349407; stages 1, 2 and 3, P(M) = 8.6 × 10(-9)), EPHA1 (rs11767557; stages 1, 2 and 3, P(M) = 6.0 × 10(-10)) and CD33 (rs3865444; stages 1, 2 and 3, P(M) = 1.6 × 10(-9)). We also replicated previous associations at CR1 (rs6701713; P(M) = 4.6 × 10(-10), P(J) = 5.2 × 10(-11)), CLU (rs1532278; P(M) = 8.3 × 10(-8), P(J) = 1.9 × 10(-8)), BIN1 (rs7561528; P(M) = 4.0 × 10(-14), P(J) = 5.2 × 10(-14)) and PICALM (rs561655; P(M) = 7.0 × 10(-11), P(J) = 1.0 × 10(-10)), but not at EXOC3L2, to late-onset Alzheimer's disease susceptibility.  相似文献   
239.
US maize yield has increased eight-fold in the past 80 years, with half of the gain attributed to selection by breeders. During this time, changes in maize leaf angle and size have altered plant architecture, allowing more efficient light capture as planting density has increased. Through a genome-wide association study (GWAS) of the maize nested association mapping panel, we determined the genetic basis of important leaf architecture traits and identified some of the key genes. Overall, we demonstrate that the genetic architecture of the leaf traits is dominated by small effects, with little epistasis, environmental interaction or pleiotropy. In particular, GWAS results show that variations at the liguleless genes have contributed to more upright leaves. These results demonstrate that the use of GWAS with specially designed mapping populations is effective in uncovering the basis of key agronomic traits.  相似文献   
240.
Thoracic aortic aneurysms and dissections are a main feature of connective tissue disorders, such as Marfan syndrome and Loeys-Dietz syndrome. We delineated a new syndrome presenting with aneurysms, dissections and tortuosity throughout the arterial tree in association with mild craniofacial features and skeletal and cutaneous anomalies. In contrast with other aneurysm syndromes, most of these affected individuals presented with early-onset osteoarthritis. We mapped the genetic locus to chromosome 15q22.2-24.2 and show that the disease is caused by mutations in SMAD3. This gene encodes a member of the TGF-β pathway that is essential for TGF-β signal transmission. SMAD3 mutations lead to increased aortic expression of several key players in the TGF-β pathway, including SMAD3. Molecular diagnosis will allow early and reliable identification of cases and relatives at risk for major cardiovascular complications. Our findings endorse the TGF-β pathway as the primary pharmacological target for the development of new treatments for aortic aneurysms and osteoarthritis.  相似文献   
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