Modeling eddy transport of passive tracers

The mean advective and eddy transport of a passive scalar property is examined. Using a theory based on rational approximation of Lagrangian particle statistics, a transport equation relating the mean eddy flux and the mean concentration field Θ is developed. The transport equation is an elaborated advection-diffusion model in which the mean eddy flux is determined by the recent history of the gradient of Θ. The flux law involves an eddy diffusivity which depends on time lag and is defined in terms of fluid particle trajectories. Particle trajectories in simulated geophysical turbulence are used to test the applicability of the restrictions upon which the model is based. Examples are given of how Θ fields are affected by the difference between an advection-diffusion model and its elaborated relative

An Experimental Investigation of the Effects of Sex and Status on Proxemic Behavior in Dyadic Interviews

Man\u27s perception of his personal space can be compared to a basic concept in the study of animal behavior, territoriality, defined by Hall as behavior by which an organism characteristically lays claim to an area and defends it against members of its own species (1966, p. 7). Territoriality was first described in 1920 by the English ornithologist H. E. Howard. He recognized events that had been noted by naturalists as far back as the seventeenth century as manifestations of territoriality (Hall, 1966). --From Chapter 1 Introduction and Rationale

Methods for estimating directional wave spectra from multi-element arrays

1. Introduction The Fourier wavenumber-frequency spectrum of a scalar variable η, with zero mean, is defined

Observations of the power and directional spectrum of ocean surface waves

Estimates of the power spectrum and directional spectrum of oceanic surface waves were obtained from data taken during the Barbados Oceanographic and Meteorological Experiment (BOMEX). Wind speeds ranged from 5 to 10 m s-1 throughout the month\u27s duration of the experiment...

The use of cognitive clinical interviews to explore learning from video game play

As research about the learning that results when children play video games becomes more popular, questions arise about what methodological and analytical tools are most appropriate to access and document this learning. Thus far, researchers have mostly adopted pre/post assessments, ethnography, and learning analytics. In this paper we (re)introduce cognitive clinical interviews as a methodology particularly suited to answering many of the most pressing questions about games and learning. To that end we describe four challenges of studying learning in video games with pre-post assessments that we claim can be addressed by the addition of clinical interviews. We then consider how clinical interviews can help to explain and describe patterns detected from ethnographic observations and detailed game play logs

The North Atlantic circulation: Combining simplified dynamics with hydrographic data

We estimate the time-averaged velocity field in the North Atlantic from observations of density, wind stress and bottom topography. The flow is assumed geostrophic, with prescribed Ekman pumping at the surface, and no normal component at the bottom. These data and dynamics determine velocity to within an arbitrary function of (Coriolis parameter)/(ocean depth), which we call the “dynamical free mode.” The free mode is selected to minimize mixing of potential density at mid-depth. This tracer-conservation criterion serves as a relatively weak constraint on the calculation. Estimates of vertical velocity are particularly sensitive to variations in the free mode and to errors in density. In contrast, horizontal velocities are relatively robust. Below the thermocline, we predict a strong O (1 cm/sec) westward flow across the entire North Atlantic, in a narrow range of latitude between 25N and 32N. This feature supports the qualitative (and controversial) conjecture by Wüst (1935) of flow along the “Mediterranean Salt Tongue.” Along continental margins and at the Mid-Atlantic Ridge, predicted bottom velocity points along isobaths, with shallow water to the right. These flows agree with many long-term current measurements and with notions of the circulation based on tracer distributions. The results conflict with previous oceanographic-inverse models, which predict mid-depth flows an order of magnitude smaller and often in opposite directions. These discrepancies may be attributable to our relatively strong enforcement of the bottom boundary condition. This involves the plausible, although tenuous, assertion that the flow “feels” only the large-scale features of the bottom topography. Our objective is to investigate the consequences of using this hypothesis to estimate the North Atlantic circulation

Performing a Comprehensive Unmanned Aircraft System Full Integration Analysis for NASA ARMD

For many years, the concept of routinely flying unmanned aircraft systems (UAS) within the national airspace system (NAS) has been a long-term goal with numerous known and unknown technology and policy obstacles. Just within the last few years, the efforts and advancements from government, industry, and academia-sponsored research and development have greatly shortened the distance to the goal. The National Aeronautics and Space Administration (NASA) Aeronautics Research Mission Directorate (ARMD) has recognized that it is uniquely positioned to play a lead role in addressing the remaining UAS airspace integration (AI) challenges. To fully understand the magnitude and scope of these challenges, NASA ARMD initiated a study in 2015 to identify what would be needed to enable full integration of UAS for civil/commercial operations within the NAS by 2025. The desired outcome was a comprehensive analysis framework that ARMD could use to develop a research portfolio focused on retiring the remaining gaps and challenges standing in the way of full UAS integration. This document is a comprehensive assessment of UAS integration research to date

α_1L-adrenoceptors mediate contraction of human erectile tissue

α1-adrenoceptor antagonists can impact upon sexual function and have potential in the treatment of erectile dysfunction. Human erectile tissue contains predominantly α1A-adrenoceptors, and here we examined whether contractions of this tissue are mediated by the functional phenotype, the α1L-adrenoceptor. Functional experiments using subtype selective agonists and antagonists, along with radioligand ([3H]tamsulosin) binding assays, were used to determine the α1-adrenoceptor population. A61603, a α1A-adrenoceptor agonist, was a full agonist with a potency 21-fold greater than that of noradrenaline. The α1A- and α1D-adrenoceptor antagonist tamsulosin antagonized noradrenaline responses with high affinity (pKD = 9.7 ± 0.3), whilst BMY7378 (100 nM) (α1D-adrenoceptor antagonist) failed to antagonize responses. In contrast, relatively low affinity estimates were obtained for both prazosin (pKD = 8.2 ± 0.1) and RS17053 (pKD = 6.9 ± 0.2), antagonists which discriminate between the α1A- and α1L-adrenoceptors. [3H]Tamsulosin bound with high affinity to the receptors of human erectile tissue (pKD = 10.3 ± 0.1) with a receptor density of 28.1 ± 1.4 fmol mg−1 protein. Prazosin displacement of [3H]tamsulosin binding revealed a single homogenous population of binding sites with a relatively low affinity for prazosin (pKi = 8.9). Taken together these data confirm that the receptor mediating contraction in human erectile tissue has the pharmacological properties of the α1L-adrenoceptor. Keywords: Erectile tissue, α1-adrenoceptor subtypes, α1L-adrenoceptor, Tamsulosin, Prazosi

Please Think Of Me

Illustration of woman\u27s face; Photograph of Tommy Dorseyhttps://scholarsjunction.msstate.edu/cht-sheet-music/12308/thumbnail.jp