2,857 research outputs found
Skull in the Ashes: Murder, a Gold Rush Manhunt, and the Birth of Circumstantial Evidence in America
Review of: "Skull in the Ashes: Murder, a Gold Rush Manhunt, and the Birth of Circumstantial Evidence in America" by Patricia Bryan
Skull in the Ashes: Murder, a Gold Rush Manhunt, and the Birth of Circumstantial Evidence in America
Review of: "Skull in the Ashes: Murder, a Gold Rush Manhunt, and the Birth of Circumstantial Evidence in America" by Patricia Bryan
Safe2Ditch Steer-To-Clear Development and Flight Testing
This paper describes a series of small unmanned aerial system (sUAS) flights performed at NASA Langley Research Center in April and May of 2019 to test a newly added Steer-to-Clear feature for the Safe2Ditch (S2D) prototype system. S2D is an autonomous crash management system for sUAS. Its function is to detect the onset of an emergency for an autonomous vehicle, and to enable that vehicle in distress to execute safe landings to avoid injuring people on the ground or damaging property. Flight tests were conducted at the City Environment Range for Testing Autonomous Integrated Navigation (CERTAIN) range at NASA Langley. Prior testing of S2D focused on rerouting to an alternate ditch site when an occupant was detected in the primary ditch site. For Steer-to-Clear testing, S2D was limited to a single ditch site option to force engagement of the Steer-to-Clear mode. The implementation of Steer-to-Clear for the flight prototype used a simple method to divide the target ditch site into four quadrants. An RC car was driven in circles in one quadrant to simulate an occupant in that ditch site. A simple implementation of Steer-to- Clear was programmed to land in the opposite quadrant to maximize distance to the occupants quadrant. A successful mission was tallied when this occurred. Out of nineteen flights, thirteen resulted in successful missions. Data logs from the flight vehicle and the RC car indicated that unsuccessful missions were due to geolocation error between the actual location of the RC car and the derived location of it by the Vision Assisted Landing component of S2D on the flight vehicle. Video data indicated that while the Vision Assisted Landing component reliably identified the location of the ditch site occupant in the image frame, the conversion of the occupants location to earth coordinates was sometimes adversely impacted by errors in sensor data needed to perform the transformation. Logged sensor data was analyzed to attempt to identify the primary error sources and their impact on the geolocation accuracy. Three trends were observed in the data evaluation phase. In one trend, errors in geolocation were relatively large at the flight vehicles cruise altitude, but reduced as the vehicle descended. This was the expected behavior and was attributed to sensor errors of the inertial measurement unit (IMU). The second trend showed distinct sinusoidal error for the entire descent that did not always reduce with altitude. The third trend showed high scatter in the data, which did not correlate well with altitude. Possible sources of observed error and compensation techniques are discussed
Toward a Model for Fisheries Social Impact Assessment
This paper presents a model for Fisheries Social Impact Assessment (SIA) that lays the groundwork for development
of fisheries-focused, quantitative social assessments with a clear conceptual model. The usefulness of current fisheries SIAâs has been called into question by some
as incompatible with approaches taken by fisheries biologists and economists when assessing potential effects of management actions. Our modelâs approach is closer to the economistsâ and biologistsâ assessments and is therefore more useful for Fishery Management Council members. The paper was developed by anthropologists initially brought together in 2004 for an SIA Modeling
Workshop by the National Marine Fisheries Service, NOAA. Opinions and conclusions expressed or implied are solely
those of the authors and do not necessarily reflect the views or policy of the National Marine Fisheries Service, NOAA
Identification of human intestinal parasites affecting an asymptomatic peri-urban Argentinian population using multi-parallel quantitative real-time polymerase chain reaction
Background: In resource-limited countries, stool microscopy is the diagnostic test of choice for intestinal parasites (soil-transmitted helminths and/or intestinal protozoa). However, sensitivity and specificity is low. Improved diagnosis of intestinal parasites is especially important for accurate measurements of prevalence and intensity of infections in endemic areas. Methods: The study was carried out in OrĂĄn, Argentina. A total of 99 stool samples from a local surveillance campaign were analyzed by concentration microscopy and McMaster egg counting technique compared to the analysis by multi-parallel quantitative real-time polymerase chain reaction (qPCR). This study compared the performance of qPCR assay and stool microscopy for 8 common intestinal parasites that infect humans including the helminths Ascaris lumbricoides, Ancylostoma duodenale, Necator americanus, Strongyloides stercoralis, Trichuris trichiura, and the protozoa Giardia lamblia, Cryptosporidium parvum/hominis, and Entamoeba histolytica, and investigated the prevalence of polyparasitism in an endemic area. Results: qPCR showed higher detection rates for all parasites as compared to stool microscopy except T. trichiura. Species-specific primers and probes were able to distinguish between A. duodenale (19.1 %) and N. americanus (36.4 %) infections. There were 48.6 % of subjects co-infected with both hookworms, and a significant increase in hookworm DNA for A. duodenale versus N. americanus (119.6 fg/ÎŒL: 0.63 fg/ÎŒL, Pâ<â0.001) respectively. qPCR outperformed microscopy by the largest margin in G. lamblia infections (63.6 % versus 8.1 %, Pâ<â0.05). Polyparasitism was detected more often by qPCR compared to microscopy (64.7 % versus 24.2 %, Pâ<â0.05). Conclusions: Multi-parallel qPCR is a quantitative molecular diagnostic method for common intestinal parasites in an endemic area that has improved diagnostic accuracy compared to stool microscopy. This first time use of multi-parallel qPCR in Argentina has demonstrated the high prevalence of intestinal parasites in a peri-urban area. These results will contribute to more accurate epidemiological survey, refined treatment strategies on a public scale, and better health outcomes in endemic settings.Fil: Cimino, RubĂ©n Oscar. Universidad Nacional de Salta; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Jeun, Rebecca. Baylor College Of Medicine; Estados UnidosFil: Juarez, Marisa. Universidad Nacional de Salta; ArgentinaFil: Cajal, Pamela S.. Universidad Nacional de Salta; ArgentinaFil: Vargas Flores, Paola Andrea. Universidad Nacional de Salta; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: EchazĂș, Adriana. Universidad Nacional de Salta; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Bryan, Patricia E.. Baylor College Of Medicine; Estados UnidosFil: Nasser, Julio RubĂ©n. Universidad Nacional de Salta; ArgentinaFil: Krolewiecki, Alejandro Javier. Universidad Nacional de Salta; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Mejia, Rojelio. Baylor College Of Medicine; Estados Unidos. Universidad Nacional de Salta; Argentin
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