North Carolina State University

About: North Carolina State University is a education organization based out in Raleigh, North Carolina, United States. It is known for research contribution in the topics: Population & Thin film. The organization has 44161 authors who have published 101744 publications receiving 3456774 citations. The organization is also known as: NCSU & North Carolina State University at Raleigh.

An Extension of the Concept of Partitioning Hereditary Variance for Analysis of Covariances among Relatives When Epistasis Is Present.

Abstract: T is convenient, for purposes of description and analysis, to consider the I phenotypic expression of a characteristic as a sum of an hereditary or genotypic value and of an environmental value, If the actual joint results deviate from this linear description (i.e., if interaction effects exist) the breeder or geneticist must exercise caution in extrapolating from his results because in this case the hereditary and environmental values are defined specifically in terms of each other ( NELDER 1950). For some characteristics a transformation of scale may help in coming closer to additivity (WRIGHT 1950). With this linear description, the total or phenotypic variance may be considered to consist of the hereditary, environmental and interaction variances, and also of covariance terms if the components are correlated in their occurrence. The covariance between heredities and environments is often a troublesome feature in human and livestock populations. For example, where dairy cattle are fed in proportion to their production, the better genotypes are provided better environments. However, in designed experiments correlation in occurrence can, for the most part, be avoided by randomization devices. FISHER ( 1918) partitioned the phenotypic variance further by subdividing the hereditary variance into an additive portion resulting from average effects of genes, a portion resulting from dominance effects (allelic interactions) of genes and a portion resulting from epistatic effects (non-allelic interactions) of genes. FISHER showed the distribution of the additive and dominance portions in correlations between various relatives in a randomly mating population. The present paper shows the subdivision of the epistatic variance into components and gives the distribution of these epistatic components in the covariances or correlations between relatives.

The concurrency workbench: a semantics-based tool for the verification of concurrent systems

Abstract: The Concurrency Workbench is an automated tool for analyzing networks of finite-state processes expressed in Milner's Calculus of Communicating Systems. Its key feature is its breadth: a variety of different verification methods, including equivalence checking, preorder checking, and model checking, are supported for several different process semantics. One experience from our work is that a large number of interesting verification methods can be formulated as combinations of a small number of primitive algorithms. The Workbench has been applied to the verification of communications protocols and mutual exclusion algorithms and has proven a valuable aid in teaching and research.

Mechanism of Phosphorescence Appropriate for the Long-Lasting Phosphors Eu2+-Doped SrAl2O4 with Codopants Dy3+ and B3+

Abstract: The existing mechanisms proposed to explain the phosphorescence of SrAl2O4:Eu2+,Dy3+ and related phosphors were found to be inconsistent with a number of important experimental and theoretical observations. We formulated a new mechanism of phosphorescence on the basis of the facts that the d orbitals of Eu2+ are located near the conduction band bottom of SrAl2O4, that the Eu2+ concentration decreases during UV excitation, and that trace amounts of Eu3+ are always present in these phosphors. In our mechanism, some Eu2+ ions are oxidized to Eu3+ under UV, and the released electrons are trapped at the oxygen vacancy levels located in the vicinity of the photogenerated Eu3+ cations. The phosphorescence arises from the recombination of these trapped electrons around the photogenerated Eu3+ sites with emission at 520 nm. The codopant Dy3+ enhances the phosphorescence by increasing the number and the depth of electron traps, and the codopant B3+ enhances the phosphorescence by increasing the depth of electron tr...

Guidelines for the Identification, Evaluation, and Management of Systemic Hypertension in Dogs and Cats

Abstract: Consensus Statements of the American College of Veterinary Internal Medicine (ACVIM) provide veterinarians with guidelines regarding the pathophysiology, diagnosis, or treatment of animal diseases. The foundation of the Consensus Statement is evidence-based medicine, but if such evidence is conflicting or lacking, the panel provides interpretive recommendations on the basis of their collective expertise. The Consensus Statement is intended to be a guide for veterinarians, but it is not a statement of standard of care or a substitute for clinical judgment. Topics of statements and panel members to draft the statements are selected by the Board of Regents with input from the general membership. A draft prepared and input from Diplomates is solicited at the ACVIM Forum and via the ACVIM Web site and incorporated in a final version. This Consensus Statement was approved by the Board of Regents of the ACVIM before publication.

Size-specific sensitivity: applying a new structured population model

Abstract: Matrix population models require the population to be divided into discrete stage classes. In many cases, especially when classes are defined by a continuous variable, such as length or mass, there are no natural breakpoints, and the division is artificial. The authors introduce the integral projection model, which eliminates the need for division into discrete classes, without requiring any additional biological assumptions. Like a traditional matrix model, the integral projection model provides estimates of the asymptotic growth rate, stable size distribution, reproductive values, and sensitivities of the growth rate to changes in vital rates. However, where the matrix model represents the size distributions, reproductive value, and sensitivities as step functions (constant within a stage class), the integral projection model yields smooth curves for each of these as a function of individual size. The authors describe a method for fitting the model to data, and they apply this method to data on an endangered plant species, northern monkshood (Aconitum noveboracense), with individuals classified by stem diameter. The matrix and integral models yield similar estimates of the asymptotic growth rate, but the reproductive values and sensitivities in the matrix model are sensitive to the choice of stage classes. The integral projection modelmore » avoids this problem and yields size-specific sensitivities that are not affected by stage duration. These general properties of the integral projection model will make it advantageous for other populations where there is no natural division of individuals into stage classes.« less