804 research outputs found
Low Velocity Airdrop Tests of an X-38 Backup Parachute Design
The NASA Johnson Space Center's X-38 program designed a new backup parachute system to recover the 25,000 lb X-38 prototype for the Crew Return Vehicle spacecraft. Due to weight and cost constraints, the main backup parachute design incorporated rapid and low cost fabrication techniques using off-the-shelf materials. Near the vent, the canopy was constructed of continuous ribbons, to provide more damage tolerance. The remainder of the canopy was a constructed with a continuous ringslot design. After cancellation of the X-38 program, the parachute design was resized, built, and drop tested for Natick Soldiers Center's Low Velocity Air Drop (LVAD) program to deliver cargo loads up to 22,000 lbs from altitudes as low as 500 feet above the ground. Drop tests results showed that the 500-foot LVAD parachute deployment conditions cause severe skirt inversion and inflation problems for large parachutes. The bag strip occurred at a high angle of attack, causing skirt inversion before the parachute could inflate. The addition of a short reefing line prevented the skirt inversion. Using a lower porosity in the vent area, than is normally used in large parachutes, improved inflation. The drop testing demonstrated that the parachute design could be refined to meet the requirements for the 500-foot LVAD mission
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Genomic analysis of heat-shock factor targets in Drosophila.
We have used a chromatin immunoprecipitation-microarray (ChIP-array) approach to investigate the in vivo targets of heat-shock factor (Hsf) in Drosophila embryos. We show that this method identifies Hsf target sites with high fidelity and resolution. Using cDNA arrays in a genomic search for Hsf targets, we identified 141 genes with highly significant ChIP enrichment. This study firmly establishes the potential of ChIP-array for whole-genome transcription factor target mapping in vivo using intact whole organisms.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are
The re-birth of the "beat": A hyperlocal online newsgathering model
This is an Author's Accepted Manuscript of an article published in Journalism Practice, 6(5-6), 754 - 765, 2012, copyright Taylor & Francis, available online at: http://www.tandfonline.com/10.1080/17512786.2012.667279.Scholars have long lamented the death of the 'beat' in news journalism. Today's journalists generate more copy than they used to, a deluge of PR releases often keeping them in the office, and away from their communities. Consolidation in industry has dislodged some journalists from their local sources. Yet hyperlocal online activity is thriving if journalists have the time and inclination to engage with it. This paper proposes an exploratory, normative schema intended to help local journalists systematically map and monitor their own hyperlocal online communities and contacts, with the aim of re-establishing local news beats online as networks. This model is, in part, technologically-independent. It encompasses proactive and reactive news-gathering and forward planning approaches. A schema is proposed, developed upon suggested news-gathering frameworks from the literature. These experiences were distilled into an iterative, replicable schema for local journalism. This model was then used to map out two real-world 'beats' for local news-gathering. Journalists working within these local beats were invited to trial the models created. It is hoped that this research will empower journalists by improving their information auditing, and could help re-define journalists' relationship with their online audiences
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Working hard on the outside: a multimodal critical discourse analysis of The Biggest Loser Australia
The Biggest Loser (TBL) is a reality television weight-loss programme that positions itself as a response to the so-called “obesity crisis”. Research on TBL has thus far focussed on audience responses and its effect on viewers’ beliefs about weight loss. This article focuses instead on how meaning is constructed in TBL. We conducted a multimodal critical discourse analysis of a key episode of TBL (the 2012 Australian season finale) to examine how the textual, visual and auditory elements combine to construct meanings beyond the ostensible health messages. Although the overt message is that all contestants have worked hard, turned their lives around and been “successful”, examination of editing choices, lighting and colour, clothing and time spent on contestants allows us to see that the programme constructs varying degrees of success between contestants and provides accounts for these differences in outcomes. In this way the programme is able to present itself as a putative celebration of all contestants while prescribing narrow limits around what constitutes success. TBL reinforces an ideology in which “success” is a direct result of “the work” of weight loss (both physical and emotional), which can apparently be read straightforwardly off the body. TBL’s “celebration” of weight loss thus reproduces and strengthens the widespread view of fat bodies as physical manifestations of individual (ir)responsibility and psychological dysfunction, and contributes to the ongoing stigmatisation of obesity
Community and the production of everyday narratives : newspaper journalists and their readers in a Spanish city.
SIGLEAvailable from British Library Document Supply Centre- DSC:DX182544 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Examining the benefit of graduated compression stockings in the prevention of hospital-associated venous thromboembolism in low-risk surgical patients: a multicentre cluster randomised controlled trial (PETS trial)
Introduction Hospital-acquired
thrombosis (HAT) is
defined as any venous thromboembolism (VTE)-related
event during a hospital admission or occurring up to 90
days post discharge, and is associated with significant
morbidity, mortality and healthcare-associated
costs.
Although surgery is an established risk factor for VTE,
operations with a short hospital stay (<48 hours) and
that permit early ambulation are associated with a low
risk of VTE. Many patients undergoing short-stay
surgical
procedures and who are at low risk of VTE are treated
with graduated compression stockings (GCS). However,
evidence for the use of GCS in VTE prevention for this
cohort is poor.
Methods and analysis A multicentre, cluster randomised
controlled trial which aims to determine whether GCS are
superior in comparison to no GCS in the prevention of VTE for
surgical patients undergoing short-stay
procedures assessed
to be at low risk of VTE. A total of 50 sites (21 472 participants)
will be randomised to either intervention (GCS) or control
(no GCS). Adult participants (18–59 years) who undergo
short-stay
surgical procedures and are assessed as low risk
of VTE will be included in the study. Participants will provide
consent to be contacted for follow-up
at 7-days
and 90-days
postsurgical procedure. The primary outcome is the rate of
symptomatic VTE, that is, deep vein thrombosis or pulmonary
embolism during admission or within 90 days. Secondary
outcomes include healthcare costs and changes in quality of
life. The main analysis will be according to the intention-to-
treat
principle and will compare the rates of VTE at 90 days,
measured at an individual level, using hierarchical (multilevel)
logistic regression.National Institute for Health Research (NIHR)	NIHR13377
The performance of pipeline ploughs traversing seabed slopes
Ploughing is a method used to bury pipelines beneath the seabed. In this method, a large purpose built plough is pulled by a support vessel to create a trench into which a pipeline is lowered. The soil that has been removed is then placed or back filled over the pipeline to provide thermal insulation, protective cover and to prevent upheaval buckling (UHB) due to pipeline thermal expansion. The majority of previous research effort has focussed on the behaviour of ploughs on level seabeds and has not investigated common geohazards such as sloping seabeds. There is also limited guidance available to industry on the limitations of ploughing on slopes. This paper reports a series of experimental tests conducted to investigate how ploughs may behave when seabed slopes are encountered and ploughing has to traverse cross-slope. The results show that ploughing operations can still be undertaken when traversing a slope but that the efficiency of operations is reduced with increasing slope inclination, leading to a reduction of trench depth and spoil heap sizes on steeper slopes. This may result in reduced pipeline cover depths on slopes if these effects cannot be mitigated
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