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51.
This paper examines the forecast accuracy of an unrestricted vector autoregressive (VAR) model for GDP, relative to a comparable vector error correction model (VECM) that recognizes that the data are characterized by co‐integration. In addition, an alternative forecast method, intercept correction, is considered for further comparison. Recursive out‐of‐sample forecasts are generated for both models and forecast techniques. The generated forecasts for each model are objectively evaluated by a selection of evaluation measures and equal accuracy tests. The result shows that the VECM consistently outperforms the VAR models. Further, intercept correction enhances the forecast accuracy when applied to the VECM, whereas there is no such indication when applied to the VAR model. For certain forecast horizons there is a significant difference in forecast ability between the intercept corrected VECM compared to the VAR model. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
52.
Cilia are essential for fertilization, respiratory clearance, cerebrospinal fluid circulation and establishing laterality. Cilia motility defects cause primary ciliary dyskinesia (PCD, MIM244400), a disorder affecting 1:15,000-30,000 births. Cilia motility requires the assembly of multisubunit dynein arms that drive ciliary bending. Despite progress in understanding the genetic basis of PCD, mutations remain to be identified for several PCD-linked loci. Here we show that the zebrafish cilia paralysis mutant schmalhans (smh(tn222)) encodes the coiled-coil domain containing 103 protein (Ccdc103), a foxj1a-regulated gene product. Screening 146 unrelated PCD families identified individuals in six families with reduced outer dynein arms who carried mutations in CCDC103. Dynein arm assembly in smh mutant zebrafish was rescued by wild-type but not mutant human CCDC103. Chlamydomonas Ccdc103/Pr46b functions as a tightly bound, axoneme-associated protein. These results identify Ccdc103 as a dynein arm attachment factor that causes primary ciliary dyskinesia when mutated.  相似文献   
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54.
Maize HapMap2 identifies extant variation from a genome in flux   总被引:3,自引:0,他引:3  
Whereas breeders have exploited diversity in maize for yield improvements, there has been limited progress in using beneficial alleles in undomesticated varieties. Characterizing standing variation in this complex genome has been challenging, with only a small fraction of it described to date. Using a population genetics scoring model, we identified 55 million SNPs in 103 lines across pre-domestication and domesticated Zea mays varieties, including a representative from the sister genus Tripsacum. We find that structural variations are pervasive in the Z. mays genome and are enriched at loci associated with important traits. By investigating the drivers of genome size variation, we find that the larger Tripsacum genome can be explained by transposable element abundance rather than an allopolyploid origin. In contrast, intraspecies genome size variation seems to be controlled by chromosomal knob content. There is tremendous overlap in key gene content in maize and Tripsacum, suggesting that adaptations from Tripsacum (for example, perennialism and frost and drought tolerance) can likely be integrated into maize.  相似文献   
55.
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   
56.
To identify somatic mutations in pediatric diffuse intrinsic pontine glioma (DIPG), we performed whole-genome sequencing of DNA from seven DIPGs and matched germline tissue and targeted sequencing of an additional 43 DIPGs and 36 non-brainstem pediatric glioblastomas (non-BS-PGs). We found that 78% of DIPGs and 22% of non-BS-PGs contained a mutation in H3F3A, encoding histone H3.3, or in the related HIST1H3B, encoding histone H3.1, that caused a p.Lys27Met amino acid substitution in each protein. An additional 14% of non-BS-PGs had somatic mutations in H3F3A causing a p.Gly34Arg alteration.  相似文献   
57.
We examined the distribution of Brechmorhoga mendax and B. pertinax (Libellulidae) in northern Arizona and southern Nevada. Brechmorhoga mendax occurs widely throughout the Southwest and in Arizona up to the Mogollon Rim, and up the Colorado River from the west to at least River Mile 132 (downstream from Lees Ferry, Arizona) at elevations of 110-1460 m. In Grand Canyon it occurs along small to large tributaries and on the mainstream at elevations below 650 m. The only previously reported locality for B. pertinax in the United States is in southeastern Arizona, where it was presumed to be accidental. We report B. pertinax along 5 small, perennial tributaries emanating from Redwall Formation aquifer springs on the south side of central Grand Canyon. Those springs habitats may be threatened by regional groundwater depletion. Brechmorhoga pertinax appears to be somewhat more stenotolerant in its habitat requirements than B. mendax , a finding in keeping with these differences in range. The presence of isolated populations of B. pertinax in Grand Canyon is an example of a Neotropical influence on the fauna and indicates biogeographic corridor and refuge functions of this large, deep canyon.  相似文献   
58.
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Construction of a 10-MWe solar thermal power plant in Daggett, California, involved clearing and leveling 53 ha of desert land. Transient offsite effects of this construction were apparent as a reduced density of annual plants within 100 m downwind of the edge of the cleared area. Schismus arabicus populations recovered within four years, but Erodium cicutarium populations did not. The effects appeared to be related more to an interaction of seed-dispersal mechanisms with the large, open space than to the obvious sand movement and deposition associated with the clearing operations.  相似文献   
59.
Primary ciliary dyskinesia (PCD) is a genetically heterogeneous autosomal recessive disorder characterized by recurrent infections of the respiratory tract associated with the abnormal function of motile cilia. Approximately half of individuals with PCD also have alterations in the left-right organization of their internal organ positioning, including situs inversus and situs ambiguous (Kartagener's syndrome). Here, we identify an uncharacterized coiled-coil domain containing a protein, CCDC40, essential for correct left-right patterning in mouse, zebrafish and human. In mouse and zebrafish, Ccdc40 is expressed in tissues that contain motile cilia, and mutations in Ccdc40 result in cilia with reduced ranges of motility. We further show that CCDC40 mutations in humans result in a variant of PCD characterized by misplacement of the central pair of microtubules and defective assembly of inner dynein arms and dynein regulatory complexes. CCDC40 localizes to motile cilia and the apical cytoplasm and is required for axonemal recruitment of CCDC39, disruption of which underlies a similar variant of PCD.  相似文献   
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