210 research outputs found
Space Launch System Booster Separation Supersonic Powered Testing with Surface and Off-Body Measurements
Get PDFA wind tunnel test was run in the NASA Langley Unitary Plan Wind Tunnel simulating the separation of the two solid rocket boosters (SRB) from the core stage of the NASA Space Launch System (SLS). The test was run on a 0.9% scale model of the SLS Block 1B Cargo (27005) configuration and the SLS Block 1B Crew (28005) configuration at a Mach of 4.0. High pressure air was used to simulate plumes from the booster separation motors located at the nose and aft skirt of the two boosters. Force and moment data were taken on both SRBs and on the core stage. Schlieren still photos and video were recorded throughout testing. A set of points were acquired using Cross-correlation Doppler Global Velocimetry (CCDGV) readings to get 3 component velocity measurements between the core and the left-hand SRB. The CCDGV laser was utilized to record flow visualization in the same location, between the core and the left-hand SRB. Pressure Sensitive Paint data were taken on a separate set of runs. Computational Fluid Dynamics (CFD) runs were computed on a subset of the wind tunnel data points for comparison. A combination of the force/moment, CCDGV and Pressure Sensitive Paint (PSP) data (as well as schlieren images) at the CFD-specified test conditions will be used te the CFD simulations that will be used to build an SLS booster separation database flight conditions
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A Phase III open-label, randomized, multicenter study of imprime pgg in combination with cetuximab in patients with kras wild type metastatic colorectal cancer
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Sex-specific effects of N-acetylcysteine in neonatal rats treated with hypothermia after severe hypoxia-ischemia
Get PDFAbstractApproximately half of moderate to severely hypoxic-ischemic (HI) newborns do not respond to hypothermia, the only proven neuroprotective treatment. N-acetylcysteine (NAC), an antioxidant and glutathione precursor, shows promise for neuroprotection in combination with hypothermia, mitigating post-HI neuroinflammation due to oxidative stress. As mechanisms of HI injury and cell death differ in males and females, sex differences must be considered in translational research of neuroprotection. We assessed the potential toxicity and efficacy of NAC in combination with hypothermia, in male and female neonatal rats after severe HI injury. NAC 50mg/kg/d administered 1h after initiation of hypothermia significantly decreased iNOS expression and caspase 3 activation in the injured hemisphere versus hypothermia alone. However, only females treated with hypothermia +NAC 50mg/kg showed improvement in short-term infarct volumes compared with saline treated animals. Hypothermia alone had no effect in this severe model. When NAC was continued for 6 weeks, significant improvement in long-term neuromotor outcomes over hypothermia treatment alone was observed, controlling for sex. Antioxidants may provide insufficient neuroprotection after HI for neonatal males in the short term, while long-term therapy may benefit both sexes
Physical activity promotion by GPs: a cross-sectional survey in England.
Get PDFBACKGROUND: Physical activity (PA) contributes to the prevention and management of many health conditions. Primary care practitioners have an important role to play in supporting people to be physically active. AIM: The study had three aims; 1) to explore general practitioners' (GPs) awareness, and knowledge of the PA guidelines, 2) to assess their confidence in promoting PA, and 3) to explore factors that influence PA promotion amongst GPs. DESIGN & SETTING: Cross-sectional survey, secondary analysis. METHOD: UK-based GPs were invited to take part in an online survey in January 2021. Demographic questions were followed by nine multiple choice questions. Categorical data were analysed using descriptive statistics and open-ended data were analysed using content analysis and inductive coding. RESULTS: Eight hundred and nine GPs based in England completed the survey. Most GP respondents (99%) believed that PA is important yet only 36% reported being at least 'somewhat familiar' with current PA guidance. Despite this, 74% of GPs reported feeling confident to raise the topic of PA with their patients. Barriers included lack of time, perceptions of patient attitude and perception of risk, language issues and COVID-19. Key facilitators were identified and 'Couch to 5 k' and the 'parkrun practice' initiative were the most widely used support tools. CONCLUSION: GPs value PA yet well-known barriers exist in embedding promotion into primary care. As primary care reconfigures there is an opportunity to embed PA into systems, services and processes
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