A note on the pseudo-spectra and the pseudo-covariance generating functions of ARMA processes

Although the spectral analysis of stationary stochastic processes has solid mathematical foundations, this is not the case for non-stationary stochastic processes. In this paper, the algebraic foundations of the spectral analysis of non-stationary ARMA processes are established. For this purpose the Fourier Transform is extended to the field of fractions of polynomials. Then, the Extended Fourier Transform pair pseudo-covariance generating function / pseudo-spectrum, analogous to the Fourier Transform pair covariance generating function / spectrum, is defined. The new transform pair is well defined for stationary and non-stationary ARMA processes. This new approach can be viewed as an extension of the classical spectral analysis. It is shown that the frequency domain has some additional algebraic advantages over the time domain

Developments in Aerospace Software Engineering practices for VSEs: An overview of the process requirements and practicesof integrated Maturity models and Standards

As part of the evolution of the Space market in the last years – globally referred to as Space 2.0 - small companies are playing an increasingly relevant role in different aerospace projects. Business incubators established by European Space Agency (ESA) and similar entities are evidence of the need of moving initiatives to small companies characterized by greater flexibility to develop specific activities. Software is a key component in most aerospace projects, and the success of the initiatives and projects usually depends on the capability of developing reliable software following well-defined standards. But small entities face some difficulties when adopting software development standards that have been conceived thinking on larger organizations and big programs. The need of defining software development standards tailored to small companies and groups is a permanent subject of discussion not only in the aerospace field, and has led in recent years to the publication of the ISO/IEC 29110 series of systems and software engineering standards and guides, aimed to solve the issues that Very Small Entities (VSEs) () – settings having up to twenty-five people -, found with other standards like CMMI or SPICE. This paper discusses the tailoring defined by different aerospace organizations for VSEs in the aerospace industry, and presents a conceptual arrangement of the standard based on meta-modeling languages that allow the extension and full customization with the incorporation of specific software engineering requirements and practices from ECSS (European Cooperation for Space Standardization)

White sands missile range non-track optics: streamlining the process of conducting business for improved customer support

Budget overruns and scheduling difficulties within the White Sands Missile Range (WSMR) test community have become more prevalent of late. Two of the biggest customer complaints have been that WSMR is too expensive, and that the scheduling process is slow and inflexible; the WSMR Non-track Optics organization has been suggested as the main contributor to these problems. WSMR Non-track Optics manages multiple types of specialized static cameras, networking instrumentation, and vehicles to transport and control its equipment, but has shown itself unable to support numerous test activities scheduled during the same timeframe. The focus of this thesis is to define the process whereby requirements for Non-track Optics support are routed, identify process inefficiencies within the organization, and recommend solutions for the Non-track Optics organization to successfully adopt the pull method, where the ability to set-up instrumentation and support exactly what the customers want, when they need it, is achieved within budget. In identifying and addressing these inefficiencies, solutions can be applied resulting in WSMR becoming a more affordable and customer-oriented test range.http://archive.org/details/whitesandsmissil1094538887DoD Civilian, Department of the Army WSMRDoD Civilian, Department of the Army JIEDDOApproved for public release; distribution is unlimited

Rapid and parallel changes in activity and mRNA of intestinal peptidase to match altered dietary protein levels in juvenile house sparrows (Passer domesticus)

Although dietary flexibility in digestive enzyme activity (i.e. reaction rate) is widespread in vertebrates, mechanisms are poorly understood. When laboratory rats are switched to a higher protein diet, the activities of apical intestinal peptidases increase within 15 h, in some cases by rapid increase in enzyme transcription followed by rapid translation and translocation to the intestine's apical, brushborder membrane (BBM). Focusing on aminopeptidase-N (APN), we studied intestinal digestive enzyme flexibility in birds, relying on activity and mRNA data from the same animals. Our model was nestling house sparrows (Passer domesticus), already known to modulate intestinal peptidase activity when switching between lower and higher protein diets. Twenty-four hours after a switch from an adequate, lower protein diet to a higher protein diet, APN activity was increased in both whole intestinal tissue homogenates and in isolated BBM, but not at 12 h post-diet switch. Twenty-four hours after a reverse switch back to the lower protein diet, APN activity was decreased, but not at 12 h post-diet switch. Changes in APN activity in both diet switch experiments were associated with parallel changes in APN mRNA. Although transcriptional changes seem to be an important mechanism underlying dietary modulation of intestinal peptidase in both nestling house sparrows and laboratory rodents, the time course for modulation in nestlings seemed slower (taking approximately twice as long) compared with laboratory rodents. It may be ecologically advantageous if nestlings biochemically restructure their gut in response to a sustained increase in insects and protein intake rather than one or a few lucky insect meals.Fil: Brun, Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Luis; Argentina. University of Wisconsin; Estados UnidosFil: Magallanes Alba, Melisa Eliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; ArgentinaFil: Karasov, William. University of Wisconsin; Estados UnidosFil: Caviedes Vidal, Enrique Juan Raul. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Luis; Argentina. University of Wisconsin; Estados Unido

Urokinase Plasminogen Activator, uPa Receptor, and Its Inhibitor in Vernal Keratoconjunctivitis

PURPOSE. Plasminogen activators play a role, not only in fibrinolysis but also in events such as chemotaxis, collagen degradation, and cell spreading. The serine protease urokinase (uPA) is a potent chemoattractant for leukocytes that may be involved in the pathogenesis of severe forms of allergic conjunctivitis such as vernal keratoconjunctivitis (VKC). METHODS. Tear and peripheral blood samples were obtained from 20 patients with active VKC and from 19 normal subjects who formed the control group. Levels of plasminogen activity, uPA, tissue plasminogen activator (tPA), and their inhibitor, plasminogen activator inhibitor type-1 (PAI-1) were measured in tears and plasma of patients with VKC. The presence of tPA, uPA, and urokinase receptor (uPAR) in conjunctival tissues were evaluated by immunohistochemistry. uPA, uPAR, and PAI-1 expression and production were measured in conjunctival epithelial cell and fibroblast cultures treated with cytokines. RESULTS. Tear levels of uPA and tPA and tear plasminogen activity levels were significantly greater in patients with VKC than in control subjects. Increased staining for uPA and uPAR was found in VKC tissues compared with normal conjunctiva. Both conjunctival epithelial cells and fibroblasts demonstrated an increased expression of uPAR after exposure to IL-4 or -13, whereas uPA was highly expressed by epithelial cells exposed to IL-4. PAI-1 levels in culture medium were increased in IL-4-exposed epithelial cells compared to nonstimulated cells and were decreased in fibroblast culture. CONCLUSIONS. Increased expression of fibrinolytic system components and imbalance between plasminogen activators and PAI may be involved in the pathogenesis of severe allergic conjunctivitis, thus contributing to inflammatory cell migration and tissue remodeling. (Invest Ophthalmol Vis Sci. 2005;46: 1364‐1370) DOI:10.1167/iovs.04-119

A fast and accurate method to identify and quantify enzymes in brush-border membranes: In situ hydrolysis followed by nano LC-MS/MS

A simple method for the identification of brush-border membrane α-glucosidases is described. The proteins were first solubilized and separated in a gel under native, non-denaturing, conditions. The gel was then incubated in substrate solutions (maltose or sucrose), and the product (glucose) exposed in situ by the oxidation of o-dianisidine, which yields a brown-orange color. Nano-liquid chromatography coupled to mass spectrometry analyses of proteins (nano LC-MS/MS) present in the colored bands excised from the gels, was used to confirm the presence of the enzymes. The stain is inexpensive and the procedure permits testing several substrates in the same gel. Once enzymes are identified, their abundance, relative to that of other proteins in the brush border, can be semi-quantified using nano LC-MS/MS.Fil: Brun, Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; ArgentinaFil: Magallanes Alba, Melisa Eliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; ArgentinaFil: Martínez del Rio, Carlos. University of Wyoming; Estados UnidosFil: Barrett Wilt, Gregory. University of Wisconsin; Estados UnidosFil: Karasov, William H.. University of Wisconsin; Estados UnidosFil: Caviedes Vidal, Enrique Juan Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; Argentin

Cardiac Hypertrophy, Accessory Pathway, and Conduction System Disease in an Adolescent

n/