1,859 research outputs found

    Identifying Reasons for a Lack of Method Application in Engineering Design Practice – An Interview Study

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    Design methods are seldom used in engineering design practice. The presented study aims at finding the alternative strategies for situations with a need for methodological support. Semi-structured interviews were conducted with ten experienced design engineers to identify causes of and strategies for those situations. Three strategy clusters could be identified: generating information, experience and method application. As the individual\u27s and the team\u27s experience compete with the application of methods, they are seen as reasons for a lack of method application

    Acceleration Of Protons To Above 6 MeV Using H2O >Snow> Nanowire Targets

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    A scheme is presented for using H2O >snow> nanowire targets for the generation of fast protons. This novel method may relax the requirements for very high laser intensities, thus reducing the size and cost of laser based ion acceleration system.Physic

    Bad expression influences time to androgen escape in prostate cancer

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    <b>OBJECTIVE</b>: To assess the role of selected downstream Bcl-2 family members (Bad, Bax, Bcl-2 and Bcl-xL) in the development of androgen-independent prostate cancer (AIPC), as androgen-deprivation therapy is the treatment of choice in advanced prostate cancer, yet patients generally relapse and progress to an AI state within 18–24 months. <b>PATIENTS, MATERIALS AND METHODS</b>: The patient cohort was established by retrospectively selecting patients with prostate cancer who had an initial response to androgen-deprivation therapy, but subsequently relapsed with AIPC. In all, 58 patients with prostate cancer were included with matched androgen-dependent (AD) and AI prostate tumours available for immunohistochemical analysis; two independent observers using a weighted-histoscore method scored the staining. Changes in Bad, Bax, Bcl-2 and Bcl-xL expression during transition to AIPC were evaluated and then correlated to known clinical variables. <b>RESULTS</b>: High Bad expression in AD tumours was associated with an increased time to biochemical relapse (<i>P</i> = 0.007) and a trend towards improved overall survival (<i>P</i> = 0.053). There were also trends towards a decrease in Bad (<i>P</i> = 0.068) and Bax (<i>P</i> = 0.055) expression with progression to AIPC. There were no significant results for Bcl-2 or Bcl-xL. <b>CONCLUSION</b>: There is evidence to suggest that Bad expression levels at diagnosis influence time to biochemical relapse and overall survival, and that levels of pro-apoptotic proteins Bad and Bax fall during AIPC development. Bad might therefore represent a possible positive prognostic marker and potential therapeutic target for AIPC in the future

    Influence of slope of rise and event order of aircraft noise events on high resolution actimetry parameters

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    Zusammenfassung: Starts und Landungen in der Nacht sind bei den meisten Verkehrsflughäfen durch eine Nachtflugsperre eingeschränkt. Die Empfindlichkeit der Bevölkerung, durch Fluglärm im Schlaf gestört zu werden, ist daher zu Randzeiten, also abends und morgens, besonders gross. In einer experimentellen Feldstudie bei Anwohnern in der Umgebung des Flughafens Zürich untersuchten wir die Wirkung von Fluglärmereignissen auf Körperreaktionen vor dem Aufwachen am Morgen. Dabei wurden in den Schlafzimmern der Versuchspersonen zuvor aufgezeichnete Fluglärm-Geräusche abgespielt. Mit einem nichtinvasiven Aufzeichnungsverfahren für schlafphysiologische Parameter (Hochauflösende Aktimetrie-, Herz- und Atemparameter) wurden Körperbewegungen ereigniskorreliert registriert. Die Resultate ergaben, dass vor allem die ersten paar Lärmereignisse am frühen Morgen die stärksten Reaktionen evozierten und diese mit zunehmender Anzahl erlebter Lärmereignisse abnehmen, was vermuten lässt, dass die zuvor erlebte Anzahl Überflüge eine systematische Wirkung hat, insbesondere wenn die Ereignisse innerhalb kurzer Zeitintervalle auftreten. Es zeigte sich auch, dass die Motilität von der Anstiegsgeschwindigkeit des Schallpegels abhängt, steilere Anstiegsflanken - wie sie typischerweise direkt unterhalb von Landeanflugschneisen auftreten - erzeugen stärkere Bewegungsreaktionen. Dies ist im Einklang mit einer neueren Untersuchung über den Zusammenhang zwischen nächtlichem Flug- und Eisenbahnlärm und Aufwachwahrscheinlichkei

    5.5-7.5 MeV Proton generation by a moderate intensity ultra-short laser interaction with H2O nano-wire targets

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    We report on the first generation of 5.5-7.5 MeV protons by a moderate intensity short-pulse laser (4.5 \times 1017 W/cm^2, 50 fsec) interacting with H2O nano-wires (snow) deposited on a Sapphire substrate. In this setup, the laser intensity is locally enhanced by the tip of the snow nano-wire, leading to high spatial gradients. Accordingly, the plasma near the tip is subject to enhanced ponderomotive potential, and confined charge separation is obtained. Electrostatic fields of extremely high intensities are produced over the short scale length, and protons are accelerated to MeV-level energies.Comment: submitted to PRL, under press embargo. 6 figure

    Multiple transcription factors directly regulate Hox gene lin-39 expression in ventral hypodermal cells of the C. elegans embryo and larva, including the hypodermal fate regulators LIN-26 and ELT-6

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    BACKGROUND: Hox genes encode master regulators of regional fate specification during early metazoan development. Much is known about the initiation and regulation of Hox gene expression in Drosophila and vertebrates, but less is known in the non-arthropod invertebrate model system, C. elegans. The C. elegans Hox gene lin-39 is required for correct fate specification in the midbody region, including the Vulval Precursor Cells (VPCs). To better understand lin-39 regulation and function, we aimed to identify transcription factors necessary for lin-39 expression in the VPCs, and in particular sought factors that initiate lin-39 expression in the embryo. RESULTS: We used the yeast one-hybrid (Y1H) method to screen for factors that bound to 13 fragments from the lin-39 region: twelve fragments contained sequences conserved between C. elegans and two other nematode species, while one fragment was known to drive reporter gene expression in the early embryo in cells that generate the VPCs. Sixteen transcription factors that bind to eight lin-39 genomic fragments were identified in yeast, and we characterized several factors by verifying their physical interactions in vitro, and showing that reduction of their function leads to alterations in lin-39 levels and lin-39::GFP reporter expression in vivo. Three factors, the orphan nuclear hormone receptor NHR-43, the hypodermal fate regulator LIN-26, and the GATA factor ELT-6 positively regulate lin-39 expression in the embryonic precursors to the VPCs. In particular, ELT-6 interacts with an enhancer that drives GFP expression in the early embryo, and the ELT-6 site we identified is necessary for proper embryonic expression. These three factors, along with the factors ZTF-17, BED-3 and TBX-9, also positively regulate lin-39 expression in the larval VPCs. CONCLUSIONS: These results significantly expand the number of factors known to directly bind and regulate lin-39 expression, identify the first factors required for lin-39 expression in the embryo, and hint at a positive feedback mechanism involving GATA factors that maintains lin-39 expression in the vulval lineage. This work indicates that, as in other organisms, the regulation of Hox gene expression in C. elegans is complicated, redundant and robust

    Current Challenges And Solution Approaches In Empirical Engineering Design Research – A Workshop For Empirical Research

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    The requirements on validity for studies in design research are very high. Therefore, this paper aims at identifying challenges that occur when setting up studies and suggests solution strategies to address them. Three different institutes combining their experience discussed several studies in a workshop. Resulting main challenges are to find a suitable task, to operationalise the variables and to deal with a high analysis effort per participant. Automation in data evaluation and a detailed practical guideline on studies in design research are considered necessary

    Learning About New Demands in Schools: Considering Algebra Policy Environments (LANDSCAPE)

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    The past three decades in mathematics education policy and research have seen a considerable focus on algebra and its place in secondary schools. Access to and success in the first high school course, most often termed Algebra I, has been framed as a civil rights issue, a harbinger of college success, and a lynchpin to global competitiveness. Policymakers have targeted access to Algebra I through universal enrollment policies at specific grade levels, while educational researchers and policy analysts have investigated the efficacy of such policies in improving student outcomes

    Componential coding in the condition monitoring of electrical machines Part 2: application to a conventional machine and a novel machine

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    This paper (Part 2) presents the practical application of componential coding, the principles of which were described in the accompanying Part 1 paper. Four major issues are addressed, including optimization of the neural network, assessment of the anomaly detection results, development of diagnostic approaches (based on the reconstruction error) and also benchmarking of componential coding with other techniques (including waveform measures, Fourier-based signal reconstruction and principal component analysis). This is achieved by applying componential coding to the data monitored from both a conventional induction motor and from a novel transverse flux motor. The results reveal that machine condition monitoring using componential coding is not only capable of detecting and then diagnosing anomalies but it also outperforms other conventional techniques in that it is able to separate very small and localized anomalies
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