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.

Evaluation of silver nanoparticle toxicity in skin in vivo and keratinocytes in vitro.

Abstract: IntroductionProducts using the antimicrobial properties of silver nanoparticles (Ag-nps) may be found in health and consumer products that routinely contact skin.ObjectivesThis study was designed t...

Chaos in a noisy world: new methods and evidence from time-series analysis

Abstract: Chaos is usually regarded as a distinct alternative to random effects such as environmental fluctuations or external disturbances. We argue that strict separation between chaotic and stochastic dynamics in ecological systems is unnecessary and misleading, and we present a more comprehensive approach for systems subject to stochastic perturbations. The defining property of chaos is sensitive dependence on initial conditions. Chaotic systems are "noise amplifiers" that magnify perturbations; nonchaotic systems are "noise mufflers" that dampen perturbations. We also present statistical methods for detecting chaos in time-series data, based on using nonlinear time-series modeling to estimate the Lyapunov exponent λ, which gives the average rate at which perturbation effects grow (λ > 0) or decay (λ < 0). These methods allow for dynamic noise and can detect low-dimensional chaos with realistic amounts of data. Results for natural and laboratory populations span the entire range from noise-dominated and strongl...

Induced-charge electrophoresis of metallodielectric particles.

Abstract: The application of ac electric fields in aqueous suspensions of anisotropic particles leads to unbalanced liquid flows and nonlinear, induced-charge electrophoretic motion. We report experimental observations of the motion of Janus microparticles with one dielectric and one metal-coated hemisphere induced by uniform fields of frequency 100 Hz-10 kHz in NaCl solutions. The motion is perpendicular to the field axis and persists after particles are attracted to a glass wall. This phenomenon may find applications in microactuators, microsensors, and microfluidic devices.

The how and why of electronic noses

Abstract: Witnessing the swift advances in the electronic means of seeing and hearing, scientists and engineers scent a market for systems mimicking the human nose. Already commercial systems from several companies are targeting applications, present and potential, that range from quality assurance of food and drugs to medical diagnosis, environmental monitoring, safety and security and military use. Here, the authors outline the major transducer technologies-in one sense, the key component of an electronic nose.

A Flexible, Multipurpose Method for Recording Vegetation Composition and Structure

Abstract: We present a flexible protocol for recording vegetation composition and structure that is appropriate for diverse applications, is scale transgressive, yields data compatible with those from commonly used methods, and is applicable across a broad range of terrestrial vegetation. The protocol is intended to be flexible in the intensity of use and commitment of time, and sufficiently open in architecture as to be adaptable to unanticipated applications. The standard observation unit is a 10 x 10 m (0.01 ha) quadrat or "module." Where the extent of homogeneous vegetation is sufficient, multiple modules are combined to form a larger, more representative sample-unit. All vascular species are recorded by cover class and in intensively sampled modules as present or absent in sets of nested quadrats. For each module, tree stems are tallied by diameter class; species with exceptionally high or low stem density can be sub- or supersampled to allow efficient collection of data and assessment of population structure. The most common plot configuration consists of 10 modules arranged in a 2 x 5 array with four modules sampled intensively; this size is often necessary to capture the complexity of a forest community. For rapid reconnaissance or inventory purposes, fewer modules are typically employed, and less information is collected.