1,152 research outputs found

    Vagal contributions to fetal heart rate variability: an omics approach

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    Fetal heart rate variability (fHRV) is an important indicator of health and disease, yet its physiological origins, neural contributions in particular, are not well understood. We aimed to develop novel experimental and data analytical approaches to identify fHRV measures reflecting the vagus nerve contributions to fHRV. In near-term ovine fetuses, a comprehensive set of 46 fHRV measures was computed from fetal pre-cordial electrocardiogram recorded during surgery and 72 hours later without (n=24) and with intra-surgical bilateral cervical vagotomy (n=15). The fetal heart rate did not change due to vagotomy. We identify fHRV measures specific to the vagal modulation of fHRV: Multiscale time irreversibility asymmetry index (AsymI), Detrended fluctuation analysis (DFA) alpha1, Kullback-Leibler permutation entropy (KLPE) and Scale dependent Lyapunov exponent slope (SDLE alpha). We provide a systematic delineation of vagal contributions to fHRV across signal-analytical domains which should be relevant for the emerging field of bioelectronic medicine and the deciphering of the vagus code. Our findings also have clinical significance for in utero monitoring of fetal health during surgery

    Variabilidade espacial de atributos físicos do solo em áreas de empréstimo para construção da hidrelétrica de Ilha Solteira (SP).

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    A retirada de espessas camadas de solo para construção de usinas hidrelétricas provoca grandes modificações ambientais, como a exposição do substrato e compactação do solo devido ao tráfego de máquinas pesadas. A análise da variabilidade espacial dos solos permite detectar estes impactos de modo eficaz e aperfeiçoa o gerenciamento das atividades futuras nestas áreas. O objetivo do trabalho foi avaliar a variabilidade espacial da estrutura, porosidade e densidade do solo em diferentes condições de uso do solo na área de empréstimo para construção da Hidrelétrica de Ilha Solteira (SP). A amostragem dos solos foi efetuada numa grade de 30 pontos de 30 x 40 m em até 0,02 m de profundidade sob os diferentes usos do solo: substrato degradado (SD); substrato com lodo de esgoto e plantado com eucalipto (SDLE); solo com pastagens (SP); capoeira em regeneração (SR) e solo sob cerrado (SC). Avaliou-se a porosidade total do solo (m3.m-3), a densidade do solo (Mg.m-3), o diâmetro médio ponderado ? DMP (mm) dos agregados determinados por via úmida e os percentuais dos agregados determinados pelo método do simulador de chuva. A análise geoestatística foi efetuada a partir do exame do parâmetro de ajuste do semivariograma, interpolação por krigagem e a construção de mapas de isolinhas. Houve dependência espacial, com alcance variando de 8 a 12 metros, nas condições de uso do solo SD e SR para os agregados, no SR para macroporosidade, porosidade total e densidade do solo, no SP para os agregados, microporosidade e porosidade total, no SC para os agregados e no LE para microporosidade. Foram identificadas manchas de dependência espacial bem definidas nos mapas dos atributos do solo, que foram caracterizados tanto por valores altos quanto baixos numa mesma área, e, portanto, torna-se inadequado considerar tais áreas como homogêneas para atividades agropecuárias futuras

    The impact of step-down line extension on consumer-brand relationships: A risky strategy for luxury brands

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    Cahiers de recherche 2011-07 E3This paper analyzes the role of the brand concept (luxury vs. non-luxury) in the impact of step-down line extension on consumer-brand relationships. A before-and-after pseudo-experimental study conducted on the Internet among BMW and Peugeot buyers shows that step-down line extension negatively influences the main variables of consumer-brand relationships (e.g., self-brand connections, brand attachment, brand trust and brand commitment) only for the luxury brand BMW. On the contrary, no dilution effects are found for the non-luxury brand Peugeot.Cet article analyse le rôle du concept de marque (luxe vs. non-luxe) dans l'impact de l'extension verticale de gamme vers le bas sur la relation consommateur-marque. Une étude expérimentale avant-après menée auprès de clients des marques BMW et Peugeot, interrogés via des clubs de possesseurs sur Internet et des forums automobiles, montre que l'extension vers le bas détériore les principales variables de la relation consommateur-marque (connexions à la marque, attachement à la marque, confiance et engagement dans la marque) pour la marque luxueuse BMW alors qu'aucun effet de dilution n'est observé pour la marque non-luxueuse Peugeot

    DSP-based ionospheric radiolink using DS-CDMA and on-line channel estimation

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    In this paper, a new blind multiuser detection algorithm is presented. It can both cancel multiuser interference and estimate the multipath channel response in a blind way. The method has been specially conceived for low coherence bandwidth channels such as the ionospheric channel and exhibits very low computational requirements. Real-time measurements from a fully digital HF radio-link are presented that confirm the reliability of the method for the ionospheric channel.Peer ReviewedPostprint (published version

    The Successful Imitation of the Japanese Lean Production System by American Firms: Impact on American Economic Growth

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    This paper provides some quantitative evidence about the strong links between the Lean Production System (LPS) or equivalently the holistic Just-in-Time/Quality Control (JIT/QC) system and sectoral (micro) economic growth. This evidence is supported by qualitative arguments that present the LPS or the JIT/QC philosophy as a major and fundamental organizational feature of modern economies. Though the implementation of such a system originated in Japan, the USA have been in the process of catching up in the last fifteen years. Subsequently, recently published American sectoral data (for the period between 1958 and 1996) are used to provide ample quantitative evidence of the role the JIT/QC organizational philosophy played in shaping and leading the American macro and sectoral economies in the last 40 years. The implications for the theory of economic growth and economic policy are also briefly stated.Lean Production, Just -in-Time, Quality Control, organization, American, Japanese, transaction costs, sectors, regression, error correction model, stationarity, total factor productivity, labor productivity, economic growth.

    Spartan Daily, February 24, 1959

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    Volume 46, Issue 77https://scholarworks.sjsu.edu/spartandaily/3856/thumbnail.jp

    Concorde noise-induced building vibrations John F. Kennedy International Airport

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    The outdoor and indoor noise levels resulting from aircraft flyovers and certain nonaircraft events were recorded at six home sites along with the associated vibration levels in the walls, windows, and floors of these test homes. Limited subjective tests conducted to examine the human detection and annoyance thresholds for building vibration and rattle caused by aircraft noise showed that both vibration and rattle were detected subjectively in several houses for some operations of both the Concorde and subsonic aircraft. Preliminary results indicate that the relationship between window vibration and aircraft noise is: (1) linear, with vibration levels being accurately predicted from OASPL levels measured near the window; (2) consistent from flyover to flyover for a given aircraft type under approach conditions; (3) no different for Concorde than for other conventional jet transports (in the case of window vibrations induced under approach power conditions); and (4) relatively high levels of window vibration measured during Concorde operations are due more to higher OASPL levels than to unique Concorde source characteristics
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