Hybrid upper surface blown flap propulsive-lift concept for the quiet short-haul research aircraft

The hybrid upper surface blowing concept consists of wing-mounted turbofan engines with a major portion of the fan exhaust directed over the wing upper surface to provide high levels of propulsive lift, but with a portion of the fan airflow directed over selected portions of the airframe to provide boundary layer control. NASA-sponsored preliminary design studies identified the hybrid upper surface blowing concept as the best propulsive lift concept to be applied to the Quiet Short-Haul Research Aircraft (QSRA) that is planned as a flight facility to conduct flight research at low noise levels high approach lift coefficients, and steep approaches. Data from NASA in-house and NASA-sponsored small and large-scale wind tunnel tests of various configurations using this concept are presented

Wind data from the 250-foot /76.2-meter/ tower at Wallops Island, Virginia

Statistical evaluation of sampled wind data from anemometers mounted on meteorological tower on Wallops Islan

Activation of Akt at T308 and S473 in alcohol, tobacco and HPV-induced HNSCC:is there evidence to support a prognostic or diagnostic role?

BACKGROUND: Tobacco, alcohol and HPV infection are associated with increased risk of HNSCC. However, little is known about the underlying signaling events influencing risk. We aimed to investigate the relationship between these risk factors and Akt phosphorylation, to determine prognostic value. METHOD: VEGF-positive HNSCC biopsies, with known HPV status, were analyzed by immunohistochemistry (IHC) for Akt, phosphorylated at residues S473 and T308. Comparisons between the tissues were carried out using a Mann–Whitney U test. Associations between the variables and continuous immunohistochemical parameters were evaluated with general linear models. Patient characteristics and pAkt IHC score were analyzed for possible association with overall survival by Cox proportional hazard models. RESULTS: Immunohistochemistry revealed that cancer patients had significantly higher levels of pAkt T308 than S473 (P < 0.001). Smoking and alcohol were found to be independent risk factors for Akt phosphorylation at T308 (P = 0.022 and 0.027, respectively). Patients with tumors positive for HPV or pAkt S473 had a poorer prognosis (P = 0.005, and 0.004, respectively). Patients who were heavy drinkers were 49 times more likely to die than non-drinkers (P = 0.003). Patients with low pAkt T308 were more likely to be HPV positive (P = 0.028). Non-drinkers were also found to have lower levels of pAkt T308 and were more likely to have tumors positive for HPV than heavy drinkers (P = 0.044 and 0.007, respectively). CONCLUSION: This study suggests different mechanisms of carcinogenesis are initiated by smoking, alcohol and HPV. Our data propose higher phosphorylation of Akt at T308 as a reliable biomarker for smoking and alcohol induced HNSCC progression and higher phosphorylation of Akt at S473 as a prognostic factor for HNSCC

LAND MARKETS AND LEGAL CONTRADICTIONS IN THE PERI-URBAN AREA OF ACCRA GHANA: INFORMANT INTERVIEWS AND SECONDARY DATA INVESTIGATIONS

The peri-urban area of Accra is experiencing a rapid transformation. A robust urban and agricultural land market has emerged, characterized by purchases, rapidly rising real land prices, and outsiders from Accra acquiring agricultural holdings for residential and commercial use. The fact that residences are being built, commercial firms are being established, and large firms are acquiring land for commercial interests attests to the ability of the customary system to enable transfers for productive activity. Nevertheless, limited or uncertain property rights increase investment costs and differential access to information in the land market affects equity. This paper seeks to better understand: (a) the land market in peri-urban Accra, (b) the process by which land held by indigenous communities is transferred to outsiders enabling the conversion of unoccupied or agricultural land into residential or commercial uses, and (c) the contradictions and frictions that exist at the interface of land transfers under customary and statutory systems. It further seeks to examine the possibility that uncertain property rights and high litigation costs are constraining commercial and agricultural investment, and to identify the economic and social factors that determine levels of premiums associated with transactions, and the duration of the customary allocation.Land tenure -- Ghana -- Accra Region, Land tenure -- Law and legislation - -Ghana, Land use, urban -- Ghana -- Accra Region, Real property -- Ghana -- Accra Region, Land reform -- Law and legislation -- Ghana, Land markets -- Ghana, Land tenure, urban -- Ghana, Land administration -- Law and legislation -- Ghana, Tenure types, Traditional -- Ghana, Research methods, Land Economics/Use,

Is there an optimal whole-body vibration exposure ‘dosage’ for performance improvement?

International Journal of Exercise Science 7(3) : 169-178, 2014. Whole-body vibration exposure has been shown to improve performance in vertical jumping and knee extensions. Some studies have addressed the question of dose optimality, but are inconclusive and inappropriately designed. Our purpose was to more thoroughly seek an optimum combination of duration, amplitude and frequency of exposure to side-alternating whole-body vibration. We used experimental designs constructed for response surface fitting and optimisation, using both blocked and unblocked second order central composite designs with 12 participants. Immediately after each exposure a discomfort index was recorded, then peak and average torque, peak and average jump height, together with peak and average jump power were recorded over three trials both pre- and post-exposure at each treatment combination. ANOVA revealed that all performance measures improved after vibration exposure. However, no successful response surface fits could be achieved for any of the performance measures, except weakly for average jump height and average jump power for a single subject. Conversely, the discomfort index increased linearly with both vibration amplitude and frequency, more steeply as exposure duration increased. We conclude that although vibration exposure has a significant positive effect on performance, its effect is so variable both between and within individuals that no real optimum can be discerned; and that high amplitudes, frequencies and durations lead to excessive discomfort

Reflection of tsunamis

Waves are reflected whenever they move into a region where their speed of propagation changes. It has generally been found that for appreciable reflection a large change in speed of propagation must occur over a distance which is small compared to a wave length...

Using ultra-thin parylene films as an organic gate insulator in nanowire field-effect transistors

We report the development of nanowire field-effect transistors featuring an ultra-thin parylene film as a polymer gate insulator. The room temperature, gas-phase deposition of parylene is an attractive alternative to oxide insulators prepared at high temperatures using atomic layer deposition. We discuss our custom-built parylene deposition system, which is designed for reliable and controlled deposition of <100 nm thick parylene films on III-V nanowires standing vertically on a growth substrate or horizontally on a device substrate. The former case gives conformally-coated nanowires, which we used to produce functional $\Omega$-gate and gate-all-around structures. These give sub-threshold swings as low as 140 mV/dec and on/off ratios exceeding $10^3$ at room temperature. For the gate-all-around structure, we developed a novel fabrication strategy that overcomes some of the limitations with previous lateral wrap-gate nanowire transistors. Finally, we show that parylene can be deposited over chemically-treated nanowire surfaces; a feature generally not possible with oxides produced by atomic layer deposition due to the surface `self-cleaning' effect. Our results highlight the potential for parylene as an alternative ultra-thin insulator in nanoscale electronic devices more broadly, with potential applications extending into nanobioelectronics due to parylene's well-established biocompatible properties