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Attention deficit hyperactivity disorder (ADHD) is a common, heritable neuropsychiatric disorder of unknown etiology. We performed a whole-genome copy number variation (CNV) study on 1,013 cases with ADHD and 4,105 healthy children of European ancestry using 550,000 SNPs. We evaluated statistically significant findings in multiple independent cohorts, with a total of 2,493 cases with ADHD and 9,222 controls of European ancestry, using matched platforms. CNVs affecting metabotropic glutamate receptor genes were enriched across all cohorts (P = 2.1 × 10(-9)). We saw GRM5 (encoding glutamate receptor, metabotropic 5) deletions in ten cases and one control (P = 1.36 × 10(-6)). We saw GRM7 deletions in six cases, and we saw GRM8 deletions in eight cases and no controls. GRM1 was duplicated in eight cases. We experimentally validated the observed variants using quantitative RT-PCR. A gene network analysis showed that genes interacting with the genes in the GRM family are enriched for CNVs in ~10% of the cases (P = 4.38 × 10(-10)) after correction for occurrence in the controls. We identified rare recurrent CNVs affecting glutamatergic neurotransmission genes that were overrepresented in multiple ADHD cohorts.  相似文献   
43.
The Black Hills of South Dakota and Wyoming are an insular mountain range completely surrounded by the Great Plains. The stonefly (Plecoptera) fauna of the Black Hills was surveyed and zoogeographic affinities examined. Twenty-seven species representing 22 genera and 6 families were found. Fifteen new state records for South Dakota and 2 for Wyoming are presented. Two species are removed from the South Dakota list. An analysis of the North American distribution of each species showed a strong relationship between the Black Hills and the Rocky Mountains, with much weaker relationships between the Black Hills and eastern and northern regions. Results of a logistic regression analysis comparing factors contributing to long-distance dispersal ability against presence/absence in the Black Hills were inconclusive. However, other evidence suggests that the Black Hills fauna is a result of expansion and subsequent vicariance of stonefly populations during Pleistocene climatic oscillations.  相似文献   
44.
The distributions of Cottus bairdi, C. rhotheus, and C. beldingi exhibited a highly significant positive degree of association. Conversely, the distribution of C. confusus exhibited a highly significant negative association with the distributional complex, C. bairdi, C. rhotheus, and C. beldingi. These species of sculpins can be grouped into two assemblages; one based on the distribution of C. confusus and the other based on the combined distributions of the other three species. The factor or factors limiting the downstream distribution of C. confusus or the upstream distribution of the other three species could not be positively identified. However, we hypothesize that competition between C. confusus and one or more members of the C. bairdi, C. rhotheus and C. beldingi complex is involved. In the area of overlapping distributions among C. bairdi, C. rhotheus, and C. bairdi we hypothesize that resource partitioning is occurring. However, the data did not allow evaluation of this hypothesis.     相似文献   
45.
A new type of vocoder system based upon formant analysis is presented in this paper. The LMS adaptive algorithm is used for tracking formants of speech signals. The results of computer simulation show that the new vocoder has better synthesized speech quality.  相似文献   
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This paper introduces the conception of open complex giant system and the methodology for dealing with the system, with stress on its profound significance in development of science and technology. The authors conclude that the reductionism underlying the exact science is not suitable to open complex giant system, and the only feasible alternative is the meta-synthetic engineering from the qualitative to the quantitative.  相似文献   
48.
This paper presents the principle of electromagnetic missile from the mathematical point of view, and verifies rigorously that the radiating power over whole space is limited.  相似文献   
49.
Fuzzy technology is a newly developed discipline based on fuzzy mathematics. In the recent years, it has been successfully applied into many areas, such as process control, diagnosis,evaluation, decision making and scheduling, especially in simulation where accurate mathematical models can not or very hard be established. In this paper, to meet the demands of fuzzy simulation, two fuzzy nets will first be presented, which are quite suitable for modeling the parallel or concurrent systems with fuzzy behavior. Then, a concept of active simulation will be introduced, in which the simulation model not only can show its fuzzy behavior, but also has a certain ability which can actively perform many very useful actions, such as automatic warning, realtime monitoring, simulation re-sult checking, simulation model self-adapting, error recovery, simulating path tracing, system states inspecting and exception handling, by a unified approach while some specified events occur. The simulation model described by this  相似文献   
50.
Metamorphic basement rocks in the Cathaysia Block are composed mainly of meta-sediments with different ages. New zircon U-Pb geochronological results from the meta-sedimentary rocks exposed in the Zengcheng and Hezi areas, southern Cathaysia Block, show that they consist dominantly of early Neoproterozoic (1.0-0.9 Ga) materials with minor Paleo- to Mesoproterozoic and late Neoproterozoic (0.8-0.6 Ga) components, suggesting that the detritus mostly come from a Grenvillian orogen. The youngest detrital zircon ages place a constraint on the deposition time of these sediments in Late Neoproterozoic. Zircon Hf isotopic compositions indicate that the Grenvillian zircons were derived from the reworking of Mesoproterozoic arc magmatic rocks and Paleoproterozoic continental crust, implying an arc-continent collisional setting. Single-peak age spectra and the presence of abundant euhedral Grenvillian zircons suggest that the sedimentary provenance is not far away from the sample location. Thus, the Grenvillian orogen probably preexisted along the southern margin of the Cathaysia Block, or very close to the south. Similarity in the ages of Grenvillian orogeny and the influence of the assembly of Gondwana in South China with India and East Antarctic are discussed, with suggestion that South China was more likely linked with the India-East Antarctica continents in Early Neoproterozoic rather than between western Laurentia and eastern Australia.  相似文献   
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