Aeroassisted-vehicle design studies for a manned Mars mission

An aerobrake design that has matured over several years of development accounting for all of the important flow phenomenology which are characteristic of aerobraking vehicles is proposed as the mission baseline. Flight regimes and aerothermal environments for both Mars and Earth entry are calculated using advanced methods to account for real-gas, thermochemical, relaxation effects. The results are correlated with thermal-protection and structural requirements and mission performance capability. The importance of nonequilibrium radiative heating for Earth aerocapture is demonstrated. It is suggested that two aerobrakes of different sizes will produce optimal performance for the three phases of the mission (i.e., one aerobrake for Mars aerocapture and descent of the surface lander and another for Earth return)

Mental Environmentalism: The True Goal of the Occupy Wall Street Movement

The purpose of this paper is to expose the actual goal behind the Occupy Wall Street Movement. The paper discusses the criticism behind the Occupy Wall Street movement for its apparent lack of goals. It then takes a retrospective look back to the establishment and founding organization, Adbusters, for answers on a “one demand” or goal. From here it will discuss the founding body, Adbusters, and its philosophical and political ideology. After this, the paper will tie facets of the Occupy Wall Street movement back to Adbusters and their philosophy of mental environmentalism in order to show that mental environmentalism was the goal of the movement all along. The paper uses newspaper sources for historical events and relies heavily on Adbusters’ founder Kalle Lasn and senior editors of the Adbusters magazine for information on mental environmentalism. It also references Kalle Lasn’s book “Culture Jam” throughout the paper. The book Culture Jam is Adbusters founder Kalle Lasn’s quasi-manifesto on how to enact a culture jamming movement, and how this alleviates the mental environment. Being that Adbusters made the call for the movement and coined the name “Occupy Wall Street,” Kalle Lasn’s book is a major part of drawing the connections between Adbusters’ goal which ultimately is the same goal as the movement

Visions

Visions, by Ella Menees, comprises four diptychs. While the paintings serve as a true exploration and celebration of color, each pair also has a distinct focus on the psychological and the unexpected. Littered with bright colors and surreal landscapes, these paintings cause the viewer to ponder all that is not shown. Each diptych presents the same subject in two different moments. The strange lighting washed over each face acts as a mask, whereas the background depicts each subject’s state of mind. Instead of “landscapes,” I consider them to be “mindscapes.” Each subject has a distinct, yet similar, experience with trauma. This connects them to one another and showcases that one never knows what is running through someone else’s head, or the past experiences that someone else carries around with them. Purposefully, no distinct statement about trauma is being dictated through these paintings, but instead, they are an exploration of inner versus outward visuals

Analytical and experimental investigations of the oblique detonation wave engine concept

Wave combustors, which include the Oblique Detonation Wave Engine (ODWE), are attractive propulsion concepts for hypersonic flight. These engines utilize oblique shock or detonation waves to rapidly mix, ignite, and combust the air-fuel mixture in thin zones in the combustion chamber. Benefits of these combustion systems include shorter and lighter engines which will require less cooling and can provide thrust at higher Mach numbers than conventional scramjets. The wave combustor's ability to operate at lower combustor inlet pressures may allow the vehicle to operate at lower dynamic pressures which could lessen the heating loads on the airframe. The research program at NASA-Ames includes analytical studies of the ODWE combustor using CFD codes which fully couple finite rate chemistry with fluid dynamics. In addition, experimental proof-of-concept studies are being carried out in an arc heated hypersonic wind tunnel. Several fuel injection designs were studied analytically and experimentally. In-stream strut fuel injectors were chosen to provide good mixing with minimal stagnation pressure losses. Measurements of flow field properties behind the oblique wave are compared to analytical predictions

Lift, Drag, and Pitching Moment of an Aspect-Ratio-2 Triangular Wing with Leading-Edge Flaps Designed to Simulate Conical Camber

An investigation was conducted to determine the effectiveness of leading-edge flaps in reducing the drag at lifting conditions of a triangular wing of aspect ratio 2.0. The flaps, deflected to simulate conically cambered wings having a wide range of design lift coefficients, were tested over a Mach number range of 0.70 to 2.22 through an angle-of-attack variation from -6 deg to +18 deg at a constant Reynolds number of 3.68 million based on the wing mean aerodynamic chord. A symmetrical wing of the same plan form and aspect ratio was also tested to provide a basis for comparison. The experimental results showed that with the flaps in the undeflected position, a small amount of fixed leading-edge droop incorporated over the outboard 5 percent of the wing semispan was as effective at high subsonic speeds as conical camber in improving the maximum lift-drag ratio above that of the symmetrical wing. At supersonic speeds, the penalty in minimum drag above that of the symmetrical wing was less than that incurred by conical camber. Deflecting the leading-edge flaps about the hinge line through 80 percent of the wing semispan resulted in further improvements of the drag characteristics at lift coefficients above 0.20 throughout the Mach number range investigated. The lift and pitching-moment characteristics were not significantly affected by the leading-edge flaps

Editorial: safety and tolerability of rifaximin for IBS – more information is required; authors' reply

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/107564/1/apt12837.pd

Wave combustors for trans-atmospheric vehicles

The Wave Combustor is an airbreathing hypersonic propulsion system which utilizes shock and detonation waves to enhance fuel-air mixing and combustion in supersonic flow. In this concept, an oblique shock wave in the combustor can act as a flameholder by increasing the pressure and temperature of the air-fuel mixture and thereby decreasing the ignition delay. If the oblique shock is sufficiently strong, then the combustion front and the shock wave can couple into a detonation wave. In this case, combustion occurs almost instantaneously in a thin zone behind the wave front. The result is a shorter, lighter engine compared to the scramjet. This engine, which is called the Oblique Detonation Wave Engine (ODWE), can then be utilized to provide a smaller, lighter vehicle or to provide a higher payload capability for a given vehicle weight. An analysis of the performance of a conceptual trans-atmospheric vehicle powered by an ODWE is given here

Static Longitudinal Stability and Control Characteristics of an Unswept Wing and Unswept Horizontal-Tail Configuration at Mach Numbers from 0.70 to 2.22

Results of an investigation of the static longitudinal stability and control characteristics of an aspect-ratio-3.1, unswept wing configuration equipped with an aspect-ratio-4, unswept horizontal tail are presented without analysis for the Mach number range from 0.70 to 2.22. The hinge line of the all-movable horizontal tail was in the extended wing chord plane, 1.66 wing mean aerodynamic chords behind the reference center of moments. The ratio of the area of the exposed horizontal-tail panels to the total area of the wing was 13.3 percent and the ratio of the total areas was 19.9 percent. Data are presented at angles of attack ranging"from -6 deg to +18 deg for the horizontal tail set at angles ranging from +5 deg to -20 deg and for the tail removed

Colorectal Cancer Screening Practices among Obstetrician/Gynecologists and Nurse Practitioners

Abstract Objective: Obstetrician/gynecologists (Ob/Gyn) and nurse practitioners (NP) are essential providers of primary and preventive care for their female patients. Therefore, colorectal cancer (CRC) screening should be part of their routine preventive practices. The purpose of our study is to evaluate the CRC screening practices of these providers. Methods: A self-administered survey was mailed to a national sample of 1130 Ob/Gyns and NPs to assess providers' demographics, current CRC screening practices, and familiarity with CRC guidelines. Results: Three hundred thirty-six providers (29.7%) returned our survey (54% Ob/Gyns and 46% NPs). Three fourths of providers routinely performed screening for CRC, compared with 95% for breast and cervical cancer. Routine CRC screening was more common among Ob/Gyns (87.2%) than NPs (61.7%) (p10 years (p<0.01), practicing in a multispecialty group (2.62 times more likely), and having an older patient population (p<0.001). Conclusions: Ob/Gyns and NPs underuse CRC screening compared with breast and cervical cancer screening and lack knowledge about appropriate use of CRC screening modalities. Opportunities to further educate Ob/Gyns and NPs should be sought to improve compliance with current CRC screening guidelines.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78151/1/jwh.2008.1117.pd

An Experimental Investigation of the Effect of a Canard Control on the Lift, Drag, and Pitching Moment of an Aspect-Ratio 2.0 Triangular Wing Incorporating a Form of Conical Camber

The results of an experimental investigation to determine the effect of a canard control on the lift, drag, and pitching-moment characteristics of an aspect-ratio-2.0 triangular wing incorporating a form of conical camber are presented. The canard had a triangular plan form of aspect ratio 2.0 and was mounted in the extended chord plane of the wing. The ratio of the area of the exposed canard panels to the total wing area was 6.9 percent, and the ratio of the total areas was 12.9 percent. Data were obtained at Mach numbers from 0.70 to 2.22 through an angle-of-attack range from -6 deg to +18 deg with the canard on, and with the canard off. To provide a basis for comparison, the canard was also tested with a symmetrical wing having the same plan form, aspect ratio, and thickness distribution as the cambered wing. The results of the investigation showed that at the high subsonic speeds the gain in maximum lift-drag ratio achieved by camber was considerably reduced by the addition of a canard. At the supersonic speeds, the addition of the canard did not change the effect of camber on the maximum lift-drag ratios