Installed performance of air-augmented nozzles based on analytical determination of internal ejector characteristics

Procedures for matching intake and ejector pumping characteristics of air-augmented nozzle

Lewis icing research tunnel test of the aerodynamic effects of aircraft ground deicing/anti-icing fluids

A wind tunnel investigation of the effect of aircraft ground deicing/anti-icing fluids on the aerodynamic characteristics of a Boeing 737-200ADV airplane was conducted. The test was carried out in the NASA Lewis Icing Research Tunnel. Fluids tested include a Newtonian deicing fluid, three non-Newtonian anti-icing fluids commercially available during or before 1988, and eight new experimental non-Newtonian fluids developed by four fluid manufacturers. The results show that fluids remain on the wind after liftoff and cause a measurable lift loss and drag increase. These effects are dependent on the high-lift configuration and on the temperature. For a configuration with a high-lift leading-edge device, the fluid effect is largest at the maximum lift condition. The fluid aerodynamic effects are related to the magnitude of the fluid surface roughness, particularly in the first 30 percent chord. The experimental fluids show a significant reduction in aerodynamic effects

Coinfection of cutaneous leishmaniasis and hiv infection

Cutaneous leishmaniasis has recently been discovered in some parts of Ghana. The case of an HIV infected patient presenting with cutaneous leishmaniasis at the Korle-Bu Teaching Hospital is discussed. The diagnosis of leishmaniasis was con-firmed by histology. Also highlighted is the fact that this is the first reported case of dual infection of HIV and Leishmaniasis in Ghana. The possibility of rapid spread to other members of the community, both immunecompetent and immunesuppressed in view of the large numbers of organisms present in the lesion is discussed

Examination of Icing Induced Loss of Control and Its Mitigations

Factors external to the aircraft are often a significant causal factor in loss of control (LOC) accidents. In today s aviation world, very few accidents stem from a single cause and typically have a number of causal factors that culminate in a LOC accident. Very often the "trigger" that initiates an accident sequence is an external environment factor. In a recent NASA statistical analysis of LOC accidents, aircraft icing was shown to be the most common external environmental LOC causal factor for scheduled operations. When investigating LOC accident or incidents aircraft icing causal factors can be categorized into groups of 1) in-flight encounter with super-cooled liquid water clouds, 2) take-off with ice contamination, or 3) in-flight encounter with high concentrations of ice crystals. As with other flight hazards, icing induced LOC accidents can be prevented through avoidance, detection, and recovery mitigations. For icing hazards, avoidance can take the form of avoiding flight into icing conditions or avoiding the hazard of icing by making the aircraft tolerant to icing conditions. Icing detection mitigations can take the form of detecting icing conditions or detecting early performance degradation caused by icing. Recovery from icing induced LOC requires flight crew or automated systems capable of accounting for reduced aircraft performance and degraded control authority during the recovery maneuvers. In this report we review the icing induced LOC accident mitigations defined in a recent LOC study and for each mitigation describe a research topic required to enable or strengthen the mitigation. Many of these research topics are already included in ongoing or planned NASA icing research activities or are being addressed by members of the icing research community. These research activities are described and the status of the ongoing or planned research to address the technology needs is discusse

The effect of motion on the perception of material appearance

We analyze the effect of motion in the perception of material appearance. First, we create a set of stimuli containing 72 realistic materials, rendered with varying degrees of linear motion blur. Then we launch a large-scale study on Mechanical Turk to rate a given set of perceptual attributes, such as brightness, roughness, or the perceived strength of reflections. Our statistical analysis shows that certain attributes undergo a significant change, varying appearance perception under motion. In addition, we further investigate the perception of brightness, for the particular cases of rubber and plastic materials. We create new stimuli, with ten different luminance levels and seven motion degrees. We launch a new user study to retrieve their perceived brightness. From the users'' judgements, we build two-dimensional maps showing how perceived brightness varies as a function of the luminance and motion of the material

Perceived Individual, Social, and Environmental Factors for Physical Activity and Walking

Background: Few studies have explored associations of individual, social, and environmental factors with physical and walking behavior. Methods: A random-digit-dial questionnaire, which included selected individual, social, and environmental variables, was administered to 2025 adults, age 18 y and older, in two adjacent counties in a southeastern state. Logistic regressions were conducted adjusting for age, race, sex, education, and employment. Results: In multivariate models, somewhat different variables were associated with physical activity versus regular walking. Self-efficacy (OR = 19.19), having an exercise partner (OR = 1.47), recreation facilities (OR = 1.54), and safety of trails from crime (OR = 0.72) were associated with physical activity level; while self-efficacy (OR = 4.22), known walking routes (OR = 1.54), recreation facilities (OR = 1.57-1.59), and safety of trails from crime (OR = 0.69) were associated with regular walking behavior. Conclusions: Physical activity and walking behaviors were associated with similar variables in this study

The Effect of Question Order on Reporting Physical Activity and Walking Behavior

Background: Question order might affect self-reported regular physical activity (PA) measured with items from the Behavioral Risk Factor Surveillance System (BRFSS) PA module. Methods: A telephone survey was conducted using 2 forms (N = 1004, N = 212) with varying PA question order. The standard form presented moderate-PA, vigorous-PA, and walking questions, in that order, whereas the alternate form presented walking questions, followed by moderate-PA, and then vigorous-PA questions. Weighted, adjusted rates of vigorous PA, walking, meeting the Centers for Disease Control and Prevention (CDC) recommendation for moderate or vigorous PA, and moderate PA from each form were compared. Results: Vigorous PA and walking were similar regardless of question order. Meeting the CDC recommendation for moderate or vigorous PA was reported less often with the alternate form among 18- to 34-year-olds. Less moderate PA was reported with the alternate form overall and among 18- to 34-year-olds, women, whites, and those with a high school education or less. Conclusion: Estimating PA and walking across sociodemographic strata with differing patterns of PA requires asking moderate-PA and vigorous-PA questions before walking questions. Asking walking questions first might lead to bias, especially for moderate PA. Walking, added to a survey with BRFSS moderate and vigorous PA items, should be placed after moderate and vigorous PA. Walking questions first may cause bias, especially for moderate PA

Physical Violence During Pregnancy: Maternal Complications and Birth Outcomes

Objective: To assess the association between physical violence during the 12 months before delivery and maternal complications and birth outcomes. Methods: We used population-based data from 6143 women who delivered live-born infants between 1993 and 1995 in South Carolina. Data on women\u27s physical violence during pregnancy were based on self-reports of partner-inflicted physical hurt and being involved in a physical fight. Outcome data included maternal antenatal hospitalizations, labor and delivery complications, low birth weights, and preterm births. Odds ratios and 95% confidence intervals were calculated to measure the associations between physical violence, maternal morbidity, and birth outcomes. Results: The prevalence of physical violence was 11.1%. Among women who experienced physical violence, 54% reported having been involved in physical fights only and 46% had been hurt by husbands or partners. In the latter group, 70% also reported having been involved in fighting. Compared with those not reporting physical violence, women who did were more likely to deliver by cesarean and be hospitalized before delivery for maternal complications such as kidney infection, premature labor, and trauma due to falls or blows to the abdomen. Conclusion: Physical violence during the 12 months before delivery is common and is associated with adverse maternal conditions. The findings support the need for research on how to screen for physical violence early in pregnancy and to prevent its consequences