Comparison of Sage and Sharp-tailed Grouse leks in south central Wyoming

Columbian Sharp-tailed Grouse ( Tympanuchus Phasianellus columnianus ) and Sage Grouse ( Centro-cercus urophasianus ) leks were compared in an area of sympatry in south central Wyoming. Sharp-tailed Grouse leks had more (P < .05 shrub cover, taller shrubs, more forb, grass, and shrub species, and less visibility than did Sage Grouse leks. Reduction in shrub cover or the diversity of herbaceous species could potentially have greater influence on the use of lek sites by Columbian Sharp-tailed Grouse than by Sage Grouse in areas of sympatry in Wyoming.     

A candidate for the cystic fibrosis locus isolated by selection for methylation-free islands

A genomic sequence close to the cystic fibrosis locus with the characteristics of an HTF island has been selectively cloned and characterized. Two markers flanking this sequence, which is conserved throughout mammalian evolution, show a very much greater disequilibrium than that found with any existing marker. A single mutational event accounts for most cases of cystic fibrosis. The sequence is expressed, and is a candidate for the cystic fibrosis gene.     

Hegel and Naturphilosophie

Against current non-metaphysical interpretations, I argue that Naturphilosophie is central to Hegel’s philosophy. This is so for three reasons. First, it was crucial to Hegel’s program to create a holistic culture. Second, Naturphilosophie is pivotal to absolute idealism, Hegel’s characteristic philosophical doctrine. Third, the idea of organic development, so central to Naturphilosophie, is pervasive throughout Hegel’s system. This idea is essential to Hegel’s concepts of spirit, dialectic, and identity-in-difference. Finally, I take issue with the neo-Kantian critique of Hegel’s Naturphilosophie on the grounds that it fails to appreciate the underlying motive behind Hegel’s system: the attempt to resolve the aporia of Kant’s epistemology.     

轿车车门断面设计的原则和方法

介绍了轿车车门断面设计的基本方法,探讨了控制断面的作用和设置原则．结合车门间隙、车门密封、车门运动校核及车门结构件连接等具体设计过程,分析了车门断面设计中需要考虑的控制要素,阐述了轿车车门断面设计的基本思路和程序．     

IgH class switching and translocations use a robust non-classical end-joining pathway

Immunoglobulin variable region exons are assembled in developing B cells by V(D)J recombination. Once mature, these cells undergo class-switch recombination (CSR) when activated by antigen. CSR changes the heavy chain constant region exons (Ch) expressed with a given variable region exon from Cmu to a downstream Ch (for example, Cgamma, Cepsilon or Calpha), thereby switching expression from IgM to IgG, IgE or IgA. Both V(D)J recombination and CSR involve the introduction of DNA double-strand breaks and their repair by means of end joining. For CSR, double-strand breaks are introduced into switch regions that flank Cmu and a downstream Ch, followed by fusion of the broken switch regions. In mammalian cells, the 'classical' non-homologous end joining (C-NHEJ) pathway repairs both general DNA double-strand breaks and programmed double-strand breaks generated by V(D)J recombination. C-NHEJ, as observed during V(D)J recombination, joins ends that lack homology to form 'direct' joins, and also joins ends with several base-pair homologies to form microhomology joins. CSR joins also display direct and microhomology joins, and CSR has been suggested to use C-NHEJ. Xrcc4 and DNA ligase IV (Lig4), which cooperatively catalyse the ligation step of C-NHEJ, are the most specific C-NHEJ factors; they are absolutely required for V(D)J recombination and have no known functions other than C-NHEJ. Here we assess whether C-NHEJ is also critical for CSR by assaying CSR in Xrcc4- or Lig4-deficient mouse B cells. C-NHEJ indeed catalyses CSR joins, because C-NHEJ-deficient B cells had decreased CSR and substantial levels of IgH locus (immunoglobulin heavy chain, encoded by Igh) chromosomal breaks. However, an alternative end-joining pathway, which is markedly biased towards microhomology joins, supports CSR at unexpectedly robust levels in C-NHEJ-deficient B cells. In the absence of C-NHEJ, this alternative end-joining pathway also frequently joins Igh locus breaks to other chromosomes to generate translocations.     

An integrated bayesian vector auto regression and error correction model for forecasting electricity consumption and prices

The analysis and forecasting of electricity consumption and prices has received considerable attention over the past forty years. In the 1950s and 1960s most of these forecasts and analyses were generated by simultaneous equation econometric models. Beginning in the 1970s, there was a shift in the modeling of economic variables from the structural equations approach with strong identifying restrictions towards a joint time-series model with very few restrictions. One such model is the vector auto regression (VAR) model. It was soon discovered that the unrestricted VAR models do not forecast well. The Bayesian vector auto regression (BVAR) approach as well the error correction model (ECM) and models based on the theory of co integration have been offered as alternatives to the simple VAR model. This paper argues that the BVAF., ECM, and co integration models are simply VAR models with various restrictions placed on the coefficients. Based on this notion of a restricted VAR model, a four-step procedure for specifying VAR forecasting models is presented and then applied to monthly data on US electricity consumption and prices.