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.

Assessing the fit of site-occupancy models

Abstract: Few species are likely to be so evident that they will always be detected at a site when present. Recently a model has been developed that enables estimation of the proportion of area occupied, when the target species is not detected with certainty. Here we apply this modeling approach to data collected on terrestrial salamanders in the Plethodon glutinosus complex in the Great Smoky Mountains National Park, USA, and wish to address the question “how accurately does the fitted model represent the data?” The goodness-of-fit of the model needs to be assessed in order to make accurate inferences. This article presents a method where a simple Pearson chi-square statistic is calculated and a parametric bootstrap procedure is used to determine whether the observed statistic is unusually large. We found evidence that the most global model considered provides a poor fit to the data, hence estimated an overdispersion factor to adjust model selection procedures and inflate standard errors. Two hypothetical datasets with known assumption violations are also analyzed, illustrating that the method may be used to guide researchers to making appropriate inferences. The results of a simulation study are presented to provide a broader view of the methods properties.

Plasmonic photocatalysts: harvesting visible light with noble metal nanoparticles

Abstract: The efforts to produce photocatalysts operating efficiently under visible light have led to a number of plasmonic photocatalysts, in which noble metal nanoparticles are deposited on the surface of polar semiconductor or insulator particles. In the metal–semiconductor composite photocatalysts, the noble metal nanoparticles act as a major component for harvesting visible light due to their surface plasmon resonance while the metal–semiconductor interface efficiently separates the photogenerated electrons and holes. In this article, we survey various plasmonic photocatalysts that have been prepared and characterized in recent years.

An Electromagnetism-like Mechanism for Global Optimization

Abstract: This paper proposes a new heuristic for global optimization. The method utilizes an attraction-repulsion mechanism to move the sample points towards the optimality. The proposed scheme can be used either as a stand-alone approach or as an accompanying procedure for other methods. Some test results on nonlinear test functions in the category of ``minor to moderate difficulty'' are included. The ease of implementation and flexibility of the heuristic show the potential of this new approach.

The Effects of Slack Resources and Environmentalthreat on Product Exploration and Exploitation

Abstract: In a U.S. sample of nonprofit professional theaters, we examine how slack resources interact with environmental threat appraisal to influence product exploration and exploitation. We find systematic variation depending on the extent to which a resource is rare and absorbed in operations, and the extent of perceived environmental threats. Absorbed, generic resources are associated with increased exploitation and decreased exploration. Unabsorbed resources, both generic and rare, result in higher exploration and lower exploitation, but only when perceived environmental threat is high. Overall, results reveal pragmatic decision making balancing the benefits of superior strategic position against the risks of jeopardizing viability.

A nomenclature for restriction enzymes, DNA methyltransferases, homing endonucleases and their genes

Abstract: A nomenclature is described for restriction endonucleases, DNA methyltransferases, homing endonucleases and related genes and gene products. It provides explicit categories for the many different Type II enzymes now identified and provides a system for naming the putative genes found by sequence analysis of microbial genomes.