73 research outputs found

    Solar Images Processing in Parallel Environment

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    This paper presents the PVA-BDA project (Processing, Visualization and Analysis in ParallelEnvironment of the BDA Data) that has been developed for processing of solar images that will be captured bythe BDA (Brazilian Decimetric Array), a radio telescope under development at the National Institute for SpaceResearch (INPE). In a joint effort between the Department of Computer Science at Federal University of SĂŁoCarlos (DC/UFSCar), the Astrophysics Division (DAS) and Associated Laboratory for Computing and AppliedMathematics (LAC) at INPE, a high performance parallel system is being developed with capacity to supportrealistic applications, involving a reasonable amount of parallel processing, in order to carry out the processing,visualization and analysis of solar images captured by BDA, in real time. The aim is to create the conditions forstarting a study of the solar weather forecast. The forecast of solar explosions are important as they may causeserious perturbations in terrestrial communication systems. An application for 3D reconstruction of X-raytomographic images of the solar atmosphere was developed at DC/UFSCar. Due to the need for the 3Dreconstruction of solar magnetic structures, in real-time, this application was implemented to execute in a parallelmachine using DSPs

    Structure-Function Analysis of STRUBBELIG, an Arabidopsis Atypical Receptor-Like Kinase Involved in Tissue Morphogenesis

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    Tissue morphogenesis in plants requires the coordination of cellular behavior across clonally distinct histogenic layers. The underlying signaling mechanisms are presently being unraveled and are known to include the cell surface leucine-rich repeat receptor-like kinase STRUBBELIG in Arabidopsis. To understand better its mode of action an extensive structure-function analysis of STRUBBELIG was performed. The phenotypes of 20 EMS and T-DNA-induced strubbelig alleles were assessed and homology modeling was applied to rationalize their possible effects on STRUBBELIG protein structure. The analysis was complemented by phenotypic, cell biological, and pharmacological investigations of a strubbelig null allele carrying genomic rescue constructs encoding fusions between various mutated STRUBBELIG proteins and GFP. The results indicate that STRUBBELIG accepts quite some sequence variation, reveal the biological importance for the STRUBBELIG N-capping domain, and reinforce the notion that kinase activity is not essential for its function in vivo. Furthermore, individual protein domains of STRUBBELIG cannot be related to specific STRUBBELIG-dependent biological processes suggesting that process specificity is mediated by factors acting together with or downstream of STRUBBELIG. In addition, the evidence indicates that biogenesis of a functional STRUBBELIG receptor is subject to endoplasmic reticulum-mediated quality control, and that an MG132-sensitive process regulates its stability. Finally, STRUBBELIG and the receptor-like kinase gene ERECTA interact synergistically in the control of internode length. The data provide genetic and molecular insight into how STRUBBELIG regulates intercellular communication in tissue morphogenesis

    A Role for Non-Antimicrobial Actions of Tetracyclines in Combating Oxidative Stress in Periodontal and Metabolic Diseases: A Literature Review

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    This review addresses the role of adjunctive tetracycline therapy in the management of periodontal diseases and its efficacy in reducing inflammatory burden, oxidative stress and its sequelae in patients with coexisting features of metabolic syndrome. Removal of the dimethylamine group at C4 of the tetracycline molecule reduces its antibiotic properties, enhancing its non-antimicrobial actions; this strategy has aided the development of several chemically modified tetracyclines such as minocycline and doxycycline, by altering different regions of the molecule for focused action on biological targets. Tetracyclines are effective in reducing inflammation by inhibiting matrix metalloproteinases, preventing excessive angiogenesis, inhibiting apoptosis and stimulating bone formation. There are important applications for tetracyclines in the management of diabetic, dyslipidaemic periodontal patients who smoke. The diverse mechanisms of action of tetracyclines in overcoming oxidative stress and enhancing matrix synthesis are discussed in this review

    ICAR: endoscopic skull‐base surgery

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    Theory and research in strategic management: Swings of a pendulum

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    The development of the field of strategic management within the last two decades has been dramatic. While its roots have been in a more applied area, often referred to as business policy, the current field of strategic management is strongly theory based, with substantial empirical research, and is eclectic in nature. This review of the development of the field and its current position examines the field’s early development and the primary theoretical and methodological bases through its history. Early developments include Chandler’s (1962) Strategy and Structure and Ansoff’s (1965) Corporate Strategy. These early works took on a contingency perspective (fit between strategy and structure) and a resource-based framework emphasizing internal strengths and weaknesses. Perhaps, one of the more significant contributions to the development of strategic management came from industrial organization (IO) economics, specifically the work of Michael Porter. The structure-conduct-performance framework and the notion of strategic groups, as well as providing a foundation for research on competitive dynamics, are flourishing currently. The IO paradigm also brought econometric tools to the research on strategic management. Building on the IO economics framework, the organizational economics perspective contributed transaction costs economics and agency theory to strategic management. More recent theoretical contributions focus on the resource-based view of the firm. While it has its roots in Edith Penrose’s work in the late 1950s, the resource-based view was largely introduced to the field of strategic management in the 1980s and became a dominant framework in the 1990s. Based on the resource-based view or developing concurrently were research on strategic leadership, strategic decision theory (process research) and knowledge-based view of the firm. The research methodologies are becoming increasingly sophisticated and now frequently combine both quantitative and qualitative approaches and unique and new statistical tools. Finally, this review examines the future directions, both in terms of theory and methodologies, as the study of strategic management evolves.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline
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