Thin film gauge

A thin film gauge for use in measuring distributed convective heat transfer rates occurring along given surfaces, is described. The gauge is particularly suited to measuring test surfaces in the air stream of a wind tunnel. The gauge is characterized by a plurality of painted platinum leads extend across the surface of a substrate; a pair of leads on the surface is adapted to deliver an electric current at a constant amperage through a selected thermally active area. Leads are also coupled at opposite sides of the thermally active area for detecting induced voltage drops occurring in the area so that the active length of the gauge is defined between voltage output leads. Changes in heat transfer to the thermally active area are isolated and determined by detecting induces changes in voltage drop

Measurement of density and temperature in a hypersonic turbulent boundary layer using the electron beam fluorescence technique

Mean density and temperature fluctuations were measured across the turbulent, cooled-wall boundary layer in a continuous hypersonic (Mach 9.4) wind tunnel in air, using the nitrogen fluorescence excited by a 50 kV electron beam. Data were taken at three values of the tunnel stagnation pressure, the corresponding free stream densities being equivalent to 1.2, 4.0, and 7.4 torr at room temperature, and the boundary layer thicknesses about 4.0, 4.5, and 6.0 inches. The mean temperature and density profiles were similar to those previously determined in the same facility by conventional probes (static and pitot pressure, total temperature). A static pressure variation of about 50% across the boundary layer was found, the shape of the variation changing somewhat for the three stagnation pressure levels. The quadrupole model for rotational temperature spectra gave closer agreement with the free stream isentropic level (approximately 44 K) than the dipole model

Entry, Descent and Landing Using Ballutes

The In Space Propulsion Program is funding a team lead by Kevin Miller at Ball Aerospace. This team of Industry, NASA, and Academic researchers is actively pursuing ballute technology development, with very promising results. The focus of that study has been to maximize the payload that is put into orbit (around Titan, Neptune, and Mars). So far the mass associated with the ballute has been minimized, because it was being thrown away. If an instrument package is attached to the Ballute, it will eventually land on the surface. Thus, the Ballute can do double duty: Aerocapture the Orbiter and Soft-land a set of instruments on the surface

HyperPASS, a New Aeroassist Tool

A new software tool designed to perform aeroassist studies has been developed by Global Aerospace Corporation (GAC). The Hypersonic Planetary Aeroassist Simulation System (HyperPASS) [1] enables users to perform guided aerocapture, guided ballute aerocapture, aerobraking, orbit decay, or unguided entry simulations at any of six target bodies (Venus, Earth, Mars, Jupiter, Titan, or Neptune). HyperPASS is currently being used for trade studies to investigate (1) aerocapture performance with alternate aeroshell types, varying flight path angle and entry velocity, different gload and heating limits, and angle of attack and angle of bank variations; (2) variable, attached ballute geometry; (3) railgun launched projectile trajectories, and (4) preliminary orbit decay evolution. After completing a simulation, there are numerous visualization options in which data can be plotted, saved, or exported to various formats. Several analysis examples will be described

Inadvertent Earth Reentry Breakup Analysis for the New Horizons Mission

The New Horizons (NH) spacecraft was launched in January 2006 aboard an Atlas V launch vehicle, in a mission to explore Pluto, its moons, and other bodies in the Kuiper Belt. The NH spacecraft is powered by a Radioisotope Thermoelectric Generator (RTG) which encases multiple General Purpose Heat Source (GPHS) modules. Thus, a pre-launch vehicle breakup analysis for an inadvertent atmospheric reentry in the event of a launch failure was required to assess aerospace nuclear safety and for launch contingency planning. This paper addresses potential accidental Earth reentries analyzed at the Jet Propulsion Laboratory (JPL) which may arise during the ascent to parking orbit, resulting in a suborbital reentry, as well as a departure from parking orbit, resulting in an orbital reentry

Enveloping Aerodynamic Decelerator

An inflatable aerodynamic deceleration method and system is provided for use with an atmospheric entry payload. The inflatable aerodynamic decelerator includes an inflatable envelope and an inflatant, wherein the inflatant is configured to fill the inflatable envelope to an inflated state such that the inflatable envelope surrounds the atmospheric entry payload, causing aerodynamic forces to decelerate the atmospheric entry payload

Attitudes towards lung cancer screening in a population sample

Background Lung cancer is the leading cause of cancer death worldwide. Routine UK lung cancer screening is not yet available, thus understanding barriers to participation in lung screening could help maximize effectiveness if introduced. Methods Population‐based survey of 1007 adults aged 16 and over in Wales using random quota sampling. Computer‐assisted face‐to‐face interviews included demographic variables (age, gender, smoking, social group), four lung cancer belief statements and three lung screening attitudinal items. Determinants of lung screening attitudes were examined using multivariable regression adjusted for age, gender, social group and previous exposure to lung campaign messages. Results Avoidance of lung screening due to fear of what might be found was statistically significantly associated with negative lung cancer beliefs including fatalism (aOR = 8.8, 95% CI = 5.6‐13.9, P ≤ 0.001), low perceived value of symptomatic presentation (aOR = 2.4, 95% CI = 1.5‐3.9, P ≤ 0.001) and low treatment efficacy (aOR = 0.3, CI = 0.2‐0.7, P ≤ 0.01). Low perceived effectiveness of lung screening was significantly associated with fatalism (aOR = 6.4, 95% CI = 3.5‐11.7, P ≤ 0.001), low perceived value of symptom presentation (aOR = 4.9, 95% CI = 2.7‐8.9, P ≤ 0.001) and low treatment efficacy (aOR = 0.1, 95% CI = 0.1‐0.3, P ≤ 0.001). In contrast, respondents who thought lung screening could reduce cancer deaths had positive beliefs about lung cancer (aOR = 0.4, 95% CI = 0.2‐0.7, P ≤ 0.001) and its treatment (aOR = 6.1, 95% CI = 3.0‐12.6, P ≤ 0.001). Conclusion People with negative beliefs about lung cancer may be more likely to avoid lung screening. Alongside the introduction of effective early detection strategies, interventions are needed to modify public perceptions of lung cancer, particularly for fatalism

Evaluation of a functional epigenetic approach to identify promoter region methylation in phaeochromocytoma and neuroblastoma

The molecular genetics of inherited phaeochromocytoma have received considerable attention, but the somatic genetic and epigenetic events that characterise tumourigenesis in sporadic phaeochromocytomas are less well defined. Previously, we found considerable overlap between patterns of promoter region tumour suppressor gene (TSG) hypermethylation in two neural crest tumours, neuroblastoma and phaeochromocytoma. In order to identify candidate biomarkers and epigenetically inactivated TSGs in phaeochromocytoma and neuroblastoma, we characterised changes in gene expression in three neuroblastoma cell lines after treatment with the demethylating agent 5-azacytidine. Promoter region methylation status was then determined for 28 genes that demonstrated increased expression after demethylation. Three genes HSP47, homeobox A9 (HOXA9) and opioid binding protein (OPCML) were methylated in >10% of phaeochromocytomas (52, 17 and 12% respectively). Two of the genes, epithelial membrane protein 3 (EMP3) and HSP47, demonstrated significantly more frequent methylation in neuroblastoma than phaeochromocytoma. These findings extend epigenotype of phaeochromocytoma and identify candidate genes implicated in sporadic phaeochromocytoma tumourigenesis

CpG methylation profiling in VHL related and VHL unrelated renal cell carcinoma

<p>Abstract</p> <p>Background</p> <p>Renal cell carcinoma (RCC) is histopathologically heterogeneous with clear cell and papillary the most common subtypes. The most frequent molecular abnormality in clear cell RCC is <it>VHL </it>inactivation but promoter methylation of tumour suppressor genes is common in both subtypes of RCC. To investigate whether RCC CpG methylation status was influenced by histopathology and <it>VHL </it>status we performed high-throughput epigenetic profiling using the Illumina Goldengate Methylation Array in 62 RCC (29 RCC from von Hippel-Lindau (VHL) disease patients, 20 sporadic clear cell RCC with wild type VHL and 13 sporadic papillary RCC).</p> <p>Results</p> <p>43 genes were methylated in >20% of primary RCC (range 20–45%) and most (37/43) of these had not been reported previously to be methylated in RCC. The distribution of the number of methylated CpGs in individual tumours differed from the expected Poisson distribution (p < 0.00001; log-likelihood G test) suggesting that a subset of RCC displayed a CpG Island Methylator Phenotype. Comparison of RCC subtypes revealed that, on average, tumour specific CpG methylation was most prevalent in papillary RCC and least in VHL RCC. Many of the genes preferentially methylated in pRCC were linked to TGFβ or ERK/Akt signalling.</p> <p>Conclusion</p> <p>These findings demonstrate differing patterns of tumour-specific CpG methylation in VHL and non VHL clear cell RCC and papillary RCC, and identify multiple novel potential CpG methylation biomarkers for RCC.</p