3,591 research outputs found
An Algorithm for Writing the Coefficients of a Polynomial with Given Zeros
Given a set of numbers {A1}=a1 âŠ., an, we may represent the sum of the products, taken r at a time, of the first k numbers of the set by S(ai,r,k). Obviously S(ai,r,k)=S(ai,r,k-l)+akS (ai,r-1,k-1) for r, k\u3e1. If in addition we define S (ai,o,k) =1 for k\u3e0 the relation holds for r,k=0. Also S(ai,r,k)=O for
Generating Waves in Corticothalamocortical Networks
In this issue of Neuron, Stroh et al. (2013) investigate mechanisms of population calcium wave initiation and propagation across cortex and thalamus. They use a novel fiber optic-based method to simultaneously image and excite specific populations of neurons in multiple regions
Judicial Approaches to the Question of Admissibility of Hypnotically Refreshed Testimony: A History and Analysis
Etiology of Persistent Microalbuminuria in Nigeria (P_MICRO study): Protocol and study design
BACKGROUND: Microalbuminuria is an independent risk factor for cardiovascular and kidney disease and a predictor of end organ damage, both in the general population and in persons with HIV (PWH). Microalbuminuria is also an important risk factor for mortality in PWH treated with antiretroviral therapy (ART). In the ongoing Renal Risk Reduction (R3) study in Nigeria, we identified a high prevalence of microalbuminuria confirmed by two measurements 4-8 weeks apart in ART-experienced, virologically suppressed PWH. Although Stage 1 or 2 hypertension and exposure to potentially nephrotoxic antiretroviral medications were common in R3 participants, other traditional risk factors for albuminuria and kidney disease, including diabetes, APOL1 high-risk genotype, and smoking were rare. Co-infection with endemic pathogens may also be significant contributors to albuminuria, but co-infections were not evaluated in the R3 study population.
METHODS: In Aim 1, we will cross-sectionally compare the prevalence of albuminuria and established kidney disease risk factors in a cohort of PWH to age- and sex-matched HIV-negative adults presenting for routine care at the Aminu Kano Teaching Hospital in Kano, Nigeria. We will leverage stored specimens from 2500 R3 participants and enroll an additional 500 PLWH recently initiated on ART (â€â24 months) and 750 age- and sex-matched HIV-negative adults to determine the contribution of HIV, hypertension, and other comorbid medical conditions to prevalent albuminuria. In Aim 2, we will follow a cohort of 1000 HIV-positive, ART-treated and 500 HIV-negative normoalbuminuric adults for 30 months to evaluate the incidence and predictors of albuminuria.
DISCUSSION: The findings from this study will support the development of interventions to prevent or address microalbuminuria in PWH to reduce kidney and cardiovascular morbidity and mortality. Such interventions might include more intensive monitoring and treatment of traditional risk factors, the provision of renin-angiotensin aldosterone system or sodium-glucose cotransporter-2 inhibitors, consideration of changes in ART regimen, and screening and treatment for relevant co-infections
Engaging citizens: local interactions, policy discourse and courses of protest against mobile phone cell site deployment
Targeted adjustment of residual stresses in hot-formed components by means of process design based on finite element simulation
The aim of this work is to generate an advantageous compressive residual stress distribution in the surface area of hot-formed components by intelligent process control with tailored cooling. Adapted cooling is achieved by partial or temporal instationary exposure of the specimens to a waterâair spray. In this way, macroscopic effects such as local plastification caused by inhomogeneous strains due to thermal and transformation-induced loads can be controlled in order to finally customise the surface-near residual stress distribution. Applications for hot-formed components often require special microstructural properties, which guarantee a certain hardness or ductility. For this reason, the scientific challenge of this work is to generate different residual stress distributions on components surfaces, while the geometric as well as microstructural properties of AISI 52100 alloy stay the same. The changes in the residual stresses should therefore not result from the mentioned changed component properties, but solely from the targeted process control. Within the scope of preliminary experimental studies, tensile residual stresses in a martensitic microstructure were determined on reference components, which had undergone a simple cooling in water (from the forming heat), or low compressive stresses in pearlitic microstructures were determined after simple cooling in atmospheric air. Numerical studies are used to design two tailored cooling strategies capable of generating compressive stresses in the same components. The developed processes with tailored cooling are experimentally realised, and their properties are compared to those of components manufactured involving simple cooling. Based on the numerical and experimental analyses, this work demonstrates that it is possible to influence and even invert the sign of the residual stresses within a component by controlling the macroscopic effects mentioned above
Multidimensional spectral estimation using iterative methods
This thesis treats the topic of multi-dimensional autoregressive (AR) spectral estimation. An iterative algorithm for the solution of toeplitz block- toeplitz matrix equations is presented. This leads to a fast solution of the two dimensional normal equation compared with direct inversion of the autocorrelation matrix. The covariance method is used to estimate the autocorrelation function. Because the resulting matrix is not toeplitz block- toeplitz, a modified iterative algorithm is presented. Quarter-plane and nonsymmetric half-plane support are used, as well as combined quadrant averaging. Results of computer simulation show that in some cases a single iteration is sufficient to produce an acceptable spectral estimate. Because the AR parameters are estimated from previous values, this suggests the possibility to estimate spectral densities of slowly varying random processes.http://archive.org/details/multidimensional1094530666Lieutenant, United States NavyApproved for public release; distribution is unlimited
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Eplucher Les Oignons (Peeling the Onions)
My creative intent is to connect with viewers at an emotional level. My chosen metaphor is âPeeling the Onion.â The implication of the metaphor is that understanding is achieved after one looks below the surface and views the underlying âlayers.â The challenge is to find images that are personally interesting and also connect with the viewer. At times the creative process proceeds in linear manner and at other times it seems to take on a life of its own. During my search for a balance between the literal and ambiguous, I explored the circle, the spiral and the sphere. Printmaking offers unique opportunities to produce evocative imagery. Drawing is the basic tool I employ to define form and my use of printmaking processes allows for evolving the image over time. The immediacy and spontaneity of my drawings is combined with a methodical approach to image development. Exploring the spiral, sphere, circles and the metaphor âPeeling the Onionâ has provided me a means of giving a form to my concepts and hopefully a connection with the viewer
Statement of Most Rev. John C. Wester on the First Anniversary of the Postville Raids
https://scholarworks.uni.edu/postville_documents/1343/thumbnail.jp
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