Evaluating System Usability, Workload Suitability, and User Experience of Game-Based Virtual Reality in Spaceflight Education and Training

Game-based instruction and immersive virtual reality are enhanced pedagogical methods beneficial in training environments involving complex disciplines, ranging from medical applications to construction engineering technology. This study investigated the use of game-based virtual reality (GBVR) when applied to the complex field of spaceflight education and training. As modern society places increasing demand on space-based amenities, the need for proficient satellite operators will also increase, requiring more accessible and advanced training options. Satellite ground control training scenarios, immersed in the GBVR environment, were developed and deployed to university student participants. Multiple validated scales were employed to measure the GBVR system regarding three main attributes: system usability, workload suitability, and user experience. Results revealed that the GBVR system usability scores ranked above average on the System Usability Scale (SUS). Secondly, the workload suitability ranked within the accepted mean value range of the National Aeronautics and Space Administration (NASA) Task Load Index (TLX). And lastly, the user experience scores were similar to popular video game scores on the Game User Experience Satisfaction Scale (GUESS-18). Even with a small sample size (n = 10), the findings indicate that GBVR is a feasible tool when applied to a complex discipline such as spaceflight education and training

Variability in Fluoroscopic X-Ray Exposure in Contemporary Cardiac Catheterization Laboratories

ObjectivesThis study sought to assess fluoroscopic exposure rates in contemporary cardiac catheterization laboratories (CCL).BackgroundIncreasing attention is being focused on X-ray exposure during diagnostic and therapeutic cardiovascular procedures.MethodsWe measured fluoroscopic exposure rates (R/min) in 41 systems using a standardized methodology (National Electrical Manufacturers Association XR21 phantom). Measurements were obtained at 2 different phantom thicknesses to simulate varying patient body habitus.ResultsFluoroscopic exposure rates under medium (median 3.0 R/min, interquartile range 1.4 R/min) and large (median 12.5 R/min, interquartile range 4.8 R/min) habitus conditions showed substantial variation. Fluoroscopic exposure was associated with simulated patient habitus, X-ray system type, vendor, and geographic region. Under medium habitus conditions, only 25% of systems operated within a zone of lower than average exposure rates and satisfactory image quality; this frequency diminished to 7% under large habitus conditions (p < 0.001).ConclusionsThere is substantial variation (4- to 6-fold) in fluoroscopic exposure rates. This variation was not consistently associated with improved image quality. In the absence of a predictable benefit of higher (or lower) than average exposure rates, CCL quality improvement programs must minimize such potentially harmful variability in X-ray exposure

Evaluating the Effectiveness of Game-Based Virtual Reality in Satellite Ground Control Operations Education and Training

There is increased global demand for satellite amenities such as navigation, communications, weather reporting, disaster management, agricultural operations, or humanitarian assistance. The growing demand for satellite technology amplifies the need for highly trained satellite operators. Traditional simulation training methods typically utilize two-dimensional computer displays. However, training approaches involving game-based instruction and immersive virtual reality have shown benefits when integrated with complex disciplines and may provide an advanced training alternative for satellite operators. Game-based instruction enhances user motivation and cognitive engagement, while immersive virtual reality promotes user presence and prolonged cognitive engagement. The combination of these two training methods, noted as game-based virtual reality, is explored in this study when integrated with a satellite operator training scenario. The study compares two groups, one training with traditional methods and one with game-based virtual reality. Both scenarios indicated significant usability scores and proper cognitive loading necessary for meaningful learning, with only minimal symptoms of simulator sickness. However, unlike the traditional method, the results of the game-based virtual reality scenario revealed significant user enjoyment and satisfaction scores. A positive and satisfying learning experience can facilitate enhanced motivation and increased cognitive engagement, fundamental to meaningful learning, denoting game-based virtual reality as a viable and effective training alternative

Two different subunits of importin cooperate to recognize nuclear localization signals and bind them to the nuclear envelope

AbstractBackground: Selective protein import into the cell nucleus occurs in two steps: binding to the nuclear envelope, followed by energy-dependent transit through the nuclear pore complex. A 60 kD protein, importin, is essential for the first nuclear import step, and the small G protein Ran/TC4 is essential for the second. We have previously purified the 60 kD importin protein (importin 60) as a single polypeptide.Results We have identified importin 90, a 90 kD second subunit that dissociates from importin 60 during affinity chromatography on nickel (II)–nitrolotriacetic acid–Sepharose, a technique that was originally used to purify importin 60. Partial amino-acid sequencing of Xenopus importin 90 allowed us to clone and sequence its human homologue; the amino-acid sequence of importin 90 is strikingly conserved between the two species. We have also identified a homologous budding yeast sequence from a database entry. Importin 90 potentiates the effects of importin 60 on nuclear protein import, indicating that the importin complex is the physiological unit responsible for import. To assess whether nuclear localization sequences are recognized by cytosolic receptor proteins, a biotin-tagged conjugate of nuclear localization signals linked to bovine serum albumin was allowed to form complexes with cytosolic proteins in Xenopus egg extracts; the complexes were then retrieved with streptavidin–agarose. The pattern of bound proteins was surprisingly simple and showed only two predominant bands: those of the importin complex. We also expressed the human homologue of importin 60, Rch1p, and found that it was able to replace its Xenopus counterpart in a functional assay. We discuss the relationship of importin 60 and importin 90 to other nuclear import factors.Conclusion Importin consists of a 60 and a 90 kD subunit. Together, they constitute a cytosolic receptor for nuclear localization signals that enables import substrates to bind to the nuclear envelope

Decreased MCM2-6 in Drosophila S2 cells does not generate significant DNA damage or cause a marked increase in sensitivity to replication interference.

A reduction in the level of some MCM proteins in human cancer cells (MCM5 in U20S cells or MCM3 in Hela cells) causes a rapid increase in the level of DNA damage under normal conditions of cell proliferation and a loss of viability when the cells are subjected to replication interference. Here we show that Drosophila S2 cells do not appear to show the same degree of sensitivity to MCM2-6 reduction. Under normal cell growth conditions a reduction of >95% in the levels of MCM3, 5, and 6 causes no significant short term alteration in the parameters of DNA replication or increase in DNA damage. MCM depleted cells challenged with HU do show a decrease in the density of replication forks compared to cells with normal levels of MCM proteins, but this produces no consistent change in the levels of DNA damage observed. In contrast a comparable reduction of MCM7 levels has marked effects on viability, replication parameters and DNA damage in the absence of HU treatment

An Estimate of Avian Mortality at Communication Towers in the United States and Canada

Avian mortality at communication towers in the continental United States and Canada is an issue of pressing conservation concern. Previous estimates of this mortality have been based on limited data and have not included Canada. We compiled a database of communication towers in the continental United States and Canada and estimated avian mortality by tower with a regression relating avian mortality to tower height. This equation was derived from 38 tower studies for which mortality data were available and corrected for sampling effort, search efficiency, and scavenging where appropriate. Although most studies document mortality at guyed towers with steady-burning lights, we accounted for lower mortality at towers without guy wires or steady-burning lights by adjusting estimates based on published studies. The resulting estimate of mortality at towers is 6.8 million birds per year in the United States and Canada. Bootstrapped subsampling indicated that the regression was robust to the choice of studies included and a comparison of multiple regression models showed that incorporating sampling, scavenging, and search efficiency adjustments improved model fit. Estimating total avian mortality is only a first step in developing an assessment of the biological significance of mortality at communication towers for individual species or groups of species. Nevertheless, our estimate can be used to evaluate this source of mortality, develop subsequent per-species mortality estimates, and motivate policy action

Diversity of the gut microbiota and eczema in early life

<p>Abstract</p> <p>Background</p> <p>A modest number of prospective studies of the composition of the intestinal microbiota and eczema in early life have yielded conflicting results.</p> <p>Objective</p> <p>To examine the relationship between the bacterial diversity of the gut and the development of eczema in early life by methods other than stool culture.</p> <p>Methods</p> <p>Fecal samples were collected from 21 infants at 1 and 4 months of life. Nine infants were diagnosed with eczema by the age of 6 months (cases) and 12 infants were not (controls). After conducting denaturating gradient gel electrophoresis (DGGE) of stool samples, we compared the microbial diversity of cases and controls using the number of electrophoretic bands and the Shannon index of diversity (<it>H'</it>) as indicators.</p> <p>Results</p> <p>Control subjects had significantly greater fecal microbial diversity than children with eczema at ages 1 (mean <it>H' </it>for controls = 0.75 vs. 0.53 for cases, P = 0.01) and 4 months (mean <it>H' </it>for controls = 0.92 vs. 0.59 for cases, P = 0.02). The increase in diversity from 1 to 4 months of age was significant in controls (P = 0.04) but not in children who developed eczema by 6 months of age (P = 0.32).</p> <p>Conclusion</p> <p>Our findings suggest that reduced microbial diversity is associated with the development of eczema in early life.</p