892 research outputs found

    Molded composite pyrogen igniter for rocket motors

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    A lightweight pyrogen igniter assembly including an elongated molded plastic tube adapted to contain a pyrogen charge was designed for insertion into a rocket motor casing for ignition of the rocket motor charge. A molded plastic closure cap provided for the elongated tube includes an ignition charge for igniting the pyrogen charge and an electrically actuated ignition squib for igniting the ignition charge. The ignition charge is contained within a portion of the closure cap, and it is retained therein by a noncorrosive ignition pellet retainer or screen which is adapted to rest on a shoulder of the elongated tube when the closure cap and tube are assembled together. A circumferentially disposed metal ring is provided along the external circumference of the closure cap and is molded or captured within the plastic cap in the molding process to provide, along with O-ring seals, a leakproof rotary joint

    The evolutionarily conserved protein CG9186 is associated with lipid droplets, required for their positioning and for fat storage.

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    Lipid droplets (LDs) are specialized cell organelles for the storage of energy-rich lipids. Although lipid storage is a conserved feature of all cells and organisms, little is known about fundamental aspects of the cell biology of LDs, including their biogenesis, structural assembly and subcellular positioning, and the regulation of organismic energy homeostasis. We identified a novel LD-associated protein family, represented by the Drosophila protein CG9186 and its murine homolog MGI:1916082. In the absence of LDs, both proteins localize at the endoplasmic reticulum (ER). Upon lipid storage induction, they translocate to LDs using an evolutionarily conserved targeting mechanism that acts through a 60-amino-acid targeting motif in the center of the CG9186 protein. Overexpression of CG9186, and MGI: 1916082, causes clustering of LDs in both tissue culture and salivary gland cells, whereas RNAi knockdown of CG9186 results in a reduction of LDs. Organismal RNAi knockdown of CG9186 results in a reduction in lipid storage levels of the fly. The results indicate that we identified the first members of a novel and evolutionarily conserved family of lipid storage regulators, which are also required to properly position LDs within cells

    The performance of irradiated CMS silicon mirco-strip detector modules

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    The central tracking system of the Compact Muon Solenoid (CMS) experiment will be entirely buil in silicon technology. The majority of the CMS tracker consists of silicon micro-strip detectors which have to be operated in the harsh environment of the Large Hadron Collider (LHC) over a period of ten years. The expected equivalent fluences range from a low of 0.7 x 10^14 n_1MeV/cm^2 at the outermost layers of the tracker, to a high of 1.6 x 10^14 n_1MeV/cm^2 at the layers closest to the interaction region. In this paper, results from studies of irradiatied CMS silicon detector modules are presented

    Recruiting and retaining young people as voluntary blood donors

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    Objectives Reasons for predonation deferral of young potential donors and prospects of recruiting and retaining young people (age 18-29) as voluntary blood donors were studied. Results Twenty-five per cent of the first-time donors recruited in 1999 remained active in 2005, but the percentage was higher among older than younger donors. Change of residency was the most frequent reason for termination of donation among young donors. Young prospect donors were more frequently than older ones deferred for lifestyle-related reasons. Prospect donors older than 30 years were more frequently deferred for health-related reasons. A large proportion (57·7%) of young adults reported a favourable attitude towards becoming blood donors. Lack of a personal request (not being asked) was the most frequently reported reason for not giving blood among young people with no donation record. Only a minor proportion of young non-donors considered themselves disqualified from donating blood due to health status. Study Design and Methods Conclusions Lifestyle-related eligibility criteria and changes of residency pose problems for recruitment and retention of young donors. However, a large proportion of young adults state that they are able and willing to donate blood; therefore, the prospects of recruiting young people as voluntary blood donors seem generally positive. Key words: blood donors, blood donor recruitment and retention. Abbreviations and definitions BBO : Blood Bank of Oslo. Active donor : a person eligible for donation, who has donated blood or plasma regularly, at least once within the last 12 months. Lapsed donor : a person who has donated blood or plasma at least once, but not within the last 12 months. Non-donor : a person who has never donated blood or plasma. Prospect donor : a person appearing for first-time donor screening, who has never previously donated either blood or plasma

    Family resilience of families with parental cancer and minor children: a qualitative analysis

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    IntroductionEstimated 50,000 minor children in Germany experience a newly diagnosed cancer in one of their parents every year. Family resilience has proven to be an important concept against life crises. However, little research exists regarding family resilience in the context of parental cancer with minor children. Based on the “Family Resilience Framework,” the aim of the study is to investigate the processes of family resilience of affected families. In addition, we explore which combinations of promoting family resilience processes can be characterized.MethodsAs part of the mixed-method quasi-experimental interventional study “F-SCOUT,” a qualitative content analysis was used to analyze the documentation of the “Family-Scouts” (a fixed contact person who advises, accompanies, and supports the families). Documentation was performed by families’ study inclusion (T0), after 3 months (T1) and 9 months (T2) concerning current family situation, organization of everyday life, emotional coping, open communication within the family, and planned tasks.ResultsThe N = 73 families had between one and six children. In 58 (79%) families, the mother had cancer. In the course of the analysis, a category system with 10 main categories and 36 subcategories emerged. Family resilience processes were described to different extents. Combinations of categories promoting family resilience were characterized by the use of social resources, flexibility, economic resources, and open communication.DiscussionThe findings are consistent with existing assumptions about family resilience in terms of the importance of social resources, family cohesion, mutual support, flexibility, open communication, and psychological well-being. In contrast to the findings of previous research, spirituality, and collaborative problem-solving indicate less centrality here. In turn, the findings on economic resources and information-seeking provide a valuable addition to the family resilience literature in the context of parental cancer with minor children.Clinical trial registrationClinicalTrials.gov, identifier NCT04186923

    Methodological approaches to determining the marine radiocarbon reservoir effect

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    The marine radiocarbon reservoir effect is an offset in 14C age between contemporaneous organisms from the terrestrial environment and organisms that derive their carbon from the marine environment. Quantification of this effect is of crucial importance for correct calibration of the <sup>14</sup>C ages of marine-influenced samples to the calendrical timescale. This is fundamental to the construction of archaeological and palaeoenvironmental chronologies when such samples are employed in <sup>14</sup>C analysis. Quantitative measurements of temporal variations in regional marine reservoir ages also have the potential to be used as a measure of process changes within Earth surface systems, due to their link with climatic and oceanic changes. The various approaches to quantification of the marine radiocarbon reservoir effect are assessed, focusing particularly on the North Atlantic Ocean. Currently, the global average marine reservoir age of surface waters, R(t), is c. 400 radiocarbon years; however, regional values deviate from this as a function of climate and oceanic circulation systems. These local deviations from R(t) are expressed as +R values. Hence, polar waters exhibit greater reservoir ages (δR = c. +400 to +800 <sup>14</sup>C y) than equatorial waters (δR = c. 0 <sup>14</sup>C y). Observed temporal variations in δR appear to reflect climatic and oceanographic changes. We assess three approaches to quantification of marine reservoir effects using known age samples (from museum collections), tephra isochrones (present onshore/offshore) and paired marine/terrestrial samples (from the same context in, for example, archaeological sites). The strengths and limitations of these approaches are evaluated using examples from the North Atlantic region. It is proposed that, with a suitable protocol, accelerator mass spectrometry (AMS) measurements on paired, short-lived, single entity marine and terrestrial samples from archaeological deposits is the most promising approach to constraining changes over at least the last 5 ky BP
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