When faced with a potential hazard, a pedestrian may need to change course, stop, maintain speed or accelerate. Logically, this must involve both a delay phase (to perceive a hazard and formulate a response) and an action phase (e.g., to arrest forward momentum in a stopping response). Qualitatively, the decision and response processes are similar to those an individual faces while driving an automobile or riding a bicycle, but very little research has been found on this subject for pedestrians. In the current study, jogging or walking subjects were asked to stop quickly in response to an auditory signal, and data were extracted from video recordings of the trials. The reaction time phase observed in the study was similar to prepared reaction times in other settings. The halting phase visibly began with a change in body angle, with rapid deceleration following the subsequent heel strike. Both the time and the distance to stop required from a jog or walk can be important for analysis of vehicle-pedestrian collisions and other mishaps.
Abstract We present studies for optimizing the next generation of ground-based imaging atmospheric Cherenkov telescopes (IACTs). Results focus on mid-sized telescopes (MSTs) for CTA, detecting very high energy gamma rays in the energy range from a few hundred GeV to a few tens of TeV. We describe a novel, flexible detector Monte Carlo package, FAST (FAst Simulation for imaging air cherenkov Telescopes), that we use to simulate different array and telescope designs. The simulation is somewhat simplified to allow for efficient exploration over a large telescope design parameter space. We investigate a wide range of telescope performance parameters including optical resolution, camera pixel size, and light collection area. In order to ensure a comparison of the arrays at their maximum sensitivity, we analyze the simulations with the most sensitive techniques used in the field, such as maximum likelihood template reconstruction and boosted decision trees for background rejection. Choosing telescope design parameters representative of the proposed Davies–Cotton (DC) and Schwarzchild–Couder (SC) MST designs, we compare the performance of the arrays by examining the gamma-ray angular resolution and differential point-source sensitivity. We further investigate the array performance under a wide range of conditions, determining the impact of the number of telescopes, telescope separation, night sky background, and geomagnetic field. We find a 30–40% improvement in the gamma-ray angular resolution at all energies when comparing arrays with an equal number of SC and DC telescopes, significantly enhancing point-source sensitivity in the MST energy range. We attribute the increase in point-source sensitivity to the improved optical point-spread function and smaller pixel size of the SC telescope design.
de la Calle Perez, I.
We present observations of the dwarf galaxies Draco and Ursa Minor, the Local Group galaxies M32 and M33, and the globular cluster M15 conducted with the Whipple 10 m gamma-ray telescope to search for the gamma-ray signature of self-annihilating weakly interacting massive particles (WIMPs), which may constitute astrophysical dark matter (DM). We review the motivations for selecting these sources based on their unique astrophysical environments and report the results of the data analysis that produced upper limits on the excess rate of gamma rays for each source. We consider models for the DM distribution in each source based on the available observational constraints and discuss possible scenarios for the enhancement of the gamma-ray luminosity. Limits on the thermally averaged product of the total self-annihilation cross section and velocity of the WIMP, , are derived using conservative estimates for the magnitude of the astrophysical contribution to the gamma-ray flux. Although these limits do not constrain predictions from the currently favored theoretical models of supersymmetry (SUSY), future observations with VERITAS will probe a larger region of the WIMP parameter phase space, , and WIMP particle mass (m(chi)).
Chemotherapy-induced nausea and vomiting (CINV) is one of the most common side effects experienced by patients receiving chemotherapy. Antiemetic medications can be used to effectively prevent and treat CINV. Choice and dose of antiemetics are often based on provider preference rather than evidenced-based information. CINV antiemetic prescribing guidelines provide an evidence-based approach and standardization for the management of this common side effect. The purpose of this quality improvement project was to improve adherence to CINV antiemetic guidelines. Despite distribution of CINV guidelines, there was inconsistent compliance with their use. When providers reported unfamiliarity with the guidelines, they were reintroduced and direct provider feedback was given to improve adherence. This quality improvement project demonstrates the need for continued reinforcement to sustain change that results in the best care for children experiencing CINV.
Rhizobium loti strain NZP 2037 and R. fredii strain USDA 217 were grown in yeast-extract media containing different sugars and polyols, and the activities of several polyol dehydrogenases were measured. The specific activities of mannitol dehydrogenase and inositol dehydrogenase were greatest in mannitol-grown cells and inositol-grown cells, respectively. Inositol dehydrogenase activity was very low or absent in cells grown in all other polyols or sugars, indicating that inositol dehydrogenase is induced in response to the presence of inositol, but not other polyols or sugars.