1,073 research outputs found
The behaviourally disturbed patient with HIV/AIDS
While HIV invades the brain early in the course of HIV infection,1 severe mental illness probably only occurs later in the disease.2 In many instances this may be the first presentation of a psychiatric illness in a younger person.In addition, the clinical syndrome may include manic and/or psychotic features, together with neurocognitive disturbance. These patients are at risk of secondary opportunistic infections or other features of systemic immunocompromise which may cause or confound the clinical picture
In Defense of Academic Free dom and Faculty Governance: John Dewey, the 100th Anniversary of the AAU P, and the Threat of Corporatization
This essay situates John Dewey in the context of the founding of the American Association of University Professors (AAUP) in 1915. We argue that the 1915 Declaration of Principles, together with World War I, provides contemporary academics important historical justification for rethinking academic freedom and faculty governance in light of neoliberalism and what we argue is an increased corporatization of higher education in the United States. By revisiting the founding of the AAUP and John Dewey’s role in the various debates surrounding the establishment of the organization—including his broader role as a public intellectual confronted by war, questions of duty and freedom, and the shifting boundaries of the professoriate—we argue that professors today should demonstrate academic freedom and reclaim faculty governance for the public good over private interests
Programmable Immersive Peripheral Environmental System (PIPES): A Prototype Control System for Environmental Feedback Devices
This paper describes an environmental feedback device (EFD) control system aimed at simplifying the VR development
cycle. Programmable Immersive Peripheral Environmental System (PIPES) affords VR developers a custom approach
to programming and controlling EFD behaviors while relaxing the required knowledge and expertise of electronic
systems. PIPES has been implemented for the Unity engine and features EFD control using the Arduino integrated
development environment. PIPES was installed and tested on two VR systems, a large format CAVE system and an
Oculus Rift HMD system. A photocell based end-to-end latency experiment was conducted to measure latency within
the system. This work extends previously unpublished prototypes of a similar design. Development and experiments
described in this paper are part of the VR community goal to understand and apply environment effects to VEs that
ultimately add to usersâ perceived presence
Plume-Free Stream Interaction Heating Effects During Orion Crew Module Reentry
During reentry of the Orion Crew Module (CM), vehicle attitude control will be performed by firing reaction control system (RCS) thrusters. Simulation of RCS plumes and their interaction with the oncoming flow has been difficult for the analysis community due to the large scarf angles of the RCS thrusters and the unsteady nature of the Orion capsule backshell environments. The model for the aerothermal database has thus relied on wind tunnel test data to capture the heating effects of thruster plume interactions with the freestream. These data are only valid for the continuum flow regime of the reentry trajectory. A Direct Simulation Monte Carlo (DSMC) analysis was performed to study the vehicle heating effects that result from the RCS thruster plume interaction with the oncoming freestream flow at high altitudes during Orion CM reentry. The study was performed with the DSMC Analysis Code (DAC). The inflow boundary conditions for the jets were obtained from Data Parallel Line Relaxation (DPLR) computational fluid dynamics (CFD) solutions. Simulations were performed for the roll, yaw, pitch-up and pitch-down jets at altitudes of 105 km, 125 km and 160 km as well as vacuum conditions. For comparison purposes (see Figure 1), the freestream conditions were based on previous DAC simulations performed without active RCS to populate the aerodynamic database for the Orion CM. Other inputs to the analysis included a constant Orbital reentry velocity of 7.5 km/s and angle of attack of 160 degrees. The results of the study showed that the interaction effects decrease quickly with increasing altitude. Also, jets with highly scarfed nozzles cause more severe heating compared to the nozzles with lower scarf angles. The difficulty of performing these simulations was based on the maximum number density and the ratio of number densities between the freestream and the plume for each simulation. The lowest altitude solutions required a substantial amount of computational resources (up to 1800 processors) to simulate approximately 2 billion molecules for the refined (adapted) solutions
Human ApoD, an apolipoprotein up-regulated in neurodegenerative diseases, extends lifespan and increases stress resistance in Drosophila
Apolipoprotein D (ApoD) expression increases in several neurological disorders and in spinal cord injury. We provide a report of a physiological role for human ApoD (hApoD): Flies overexpressing hApoD are long-lived and protected against stress conditions associated with aging and neurodegeneration, including hyperoxia, dietary paraquat, and heat stress. We show that the fly ortholog, Glial Lazarillo, is strongly up-regulated in response to these extrinsic stresses and also can protect in vitro-cultured cells in situations modeling Alzheimer's disease (AD) and Parkinson's disease (PD). In adult flies, hApoD overexpression reduces age-associated lipid peroxide accumulation, suggesting a proximal mechanism of action. Similar data obtained in the mouse [Ganfornina, M.D., et al., (2008) Apolipoprotein D is involved in the mechanisms regulating protection from oxidative stress. Aging Cell 10.1111/j.1474-9726.2008.00395.] as well as in plants (Charron et al., personal communication) suggest that ApoD and its orthologs play an evolutionarily conserved role in response to stress, possibly managing or preventing lipid peroxidation
Plant pathogens provide clues to the potential origin of bat white-nose syndromePseudogymnoascus destructans
White-nose syndrome has killed millions of bats, yet both the origins and infection strategy of the causative fungus, Pseudogymnoascus destructans, remain elusive. We provide evidence for a novel hypothesis that P. destructans emerged from plant-associated fungi and retained invasion strategies affiliated with fungal pathogens of plants. We demonstrate that P. destructans invades bat skin in successive biotrophic and necrotrophic stages (hemibiotrophic infection), a mechanism previously only described in plant fungal pathogens. Further, the convergence of hyphae at hair follicles suggests nutrient tropism. Tropism, biotrophy, and necrotrophy are often associated with structures termed appressoria in plant fungal pathogens; the penetrating hyphae produced by P. destructans resemble appressoria. Finally, we conducted a phylogenomic analysis of a taxonomically diverse collection of fungi. Despite gaps in genetic sampling of prehistoric and contemporary fungal species, we estimate an 88% probability the ancestral state of the clade containing P. destructans was a plant-associated fungus
Snowmobiles in Antarctica
Snowmobiles are the main form of land transportation for field parties in Antarctica. Recently the United States Antarctic program turned almost exclusively to Ski-Doo Alpine 640-ER snowmobiles, the use and maintenance of which require specialized techniques. The first extensive Antarctic field test of these snowmobiles was made during three months of 1977-1978 while engaged in reconnaissance geologic and topographic exploration of the Orville Coast area. Snowmobiles are used to pull large loads of food and gear on two Nansen sledges. When crossing crevasse fields, they are driven remotely by persons on skis. To do this, modifications are made to the stock throttle to enable the engine both to be set at a constant speed and to be shorted out by pulling on a cord that trails behind the snowmobile; steering is by ropes attached to the front ski of the snowmobile. Proper "night" storage is necessary to ensure easiest starting in the morning and to minimize the effects of storms. A routine of trouble-shooting that rapidly isolated and corrected engine problems included first checking spark-plugs or gas-line filters, followed by checking carburetor jet adjustments, drive belt and oil/gas ratio. We found that Ski-Doos are well suited to Antarctica but would be more useful if carburetor fuel filters were replaced by in-line fuel filters and if snowmobiles were equipped with remote throttle controls, tachometers, speedometers, odometers, and a low-gear option
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