922 research outputs found

    Paper Session I-B - The Human Space Flight Approach to Crew Resource Mangement

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    She was carrying more than 2220 passengers when she left the Southampton docks just after noon on that April day. This maiden voyage of discovery and adventure would soon become one of the most devastating maritime disasters of all time as the great ship collided with an iceberg, only minutes before midnight on April 14, 88 years ago. In just under 3 short hours, the freezing waters of the North Atlantic swallowed the Titanic ending the lives of over 1500 of her passengers and crew, forever changing those of the 707 survivors. In the early hours of the morning on April 26, 1986 a routine test of the reactor went very wrong. The nuclear power control engineers at Chernobyl unit 4 had no idea that their actions were about to produce the worst nuclear disaster of all time. Several human errors led to an uncontrolled reaction in the core resulting in explosions that lifted the cap off the containment facility. In all some 8 tons of fuel containing highly radioactive plutonium and other fission products were ejected from the reactor into the surrounding atmosphere

    The Consistency of Repeated Witness Testimony Leads Triers-of-Fact to Over-Rely on the Power of a Single Voice

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    Are claims more credible when made by multiple people, or is it the repetition of claims that matters? Some research suggests that claims have more credibility when independent sources make them. Yet, other research suggests that simply repeating information makes it more accessible and encourages reliance on automatic processes—factors known to change people’s judgments. In Experiment 1, subjects took part in a “misinformation” study: Subjects first watched a video of a crime and later read witness reports attributed to one or three different witnesses who made misleading claims in either one report or repeated the same misleading claims across all three reports. In Experiment 2, subjects who had not seen any videos read those same reports and indicated how confident they were that each claim happened in the original event. Subjects were more misled by—and more confident about—claims that were repeated, regardless of how many witnesses made them. These findings led us to hypothesize that the repeated claims of a single witness are seen as consistent, while the claims of multiple witnesses are seen as having consensus. We tested this hypothesis in Experiments 3 and 4 by asking subjects who had not seen the video to read the reports that repeated the claims. In Experiment 3, half of the subjects read reports that contained some peripheral inconsistencies. In Experiment 4 all subjects read reports that contained inconsistencies, but half of the subjects were warned about the accuracy of the inconsistent reports. Later, everyone indicated how confident they were that each claim really happened. Warning subjects about the inconsistent reports (Experiment 4) led them to rate the repeated claims of a single witness—but not multiple witnesses—as less credible; A finding consistent with our hypothesis. In Experiment 5, we tested an alternative explanation that a failure to attend to the source of the information may explain our findings by asking half of the subjects to complete a source monitoring component with their confidence test. We failed to find evidence for this explanation. We conclude that subjects interpreted both the consistency of a single witness's repeated claims, and the consensus among multiple witnesses' converging claims, as markers of accuracy. Importantly, warning subjects about the accuracy of the inconsistent reports reduced subjects’ confidence in the claims made by a single witness, but not multiple witnesses. These findings fit with research showing that repeating information makes it seem more true, and highlight the power of a single repeated voice

    Intestinal Dipeptide Absorption Is Preserved During Thermal Injury and Cytokine Treatment

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142293/1/jpen0520.pd

    Excitatory and inhibitory projections in parallel pathways from the inferior colliculus to the auditory thalamus

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    Individual subdivisions of the medial geniculate body (MG) receive a majority of their ascending inputs from 1 or 2 subdivisions of the inferior colliculus (IC). This establishes parallel pathways that provide a model for understanding auditory projections from the IC through the MG and on to auditory cortex. A striking discovery about the tectothalamic circuit was identification of a substantial GABAergic component. Whether GABAergic projections match the parallel pathway organization has not been examined. We asked whether the parallel pathway concept is reflected in guinea pig tectothalamic pathways and to what degree GABAergic cells contribute to each pathway. We deposited retrograde tracers into individual MG subdivisions (ventral, MGv; medial, MGm; dorsal, MGd; suprageniculate, MGsg) to label tectothalamic cells and used immunochemistry to identify GABAergic cells. The MGv receives most of its IC input (~75%) from the IC central nucleus (ICc); MGd and MGsg receive most of their input (~70%) from IC dorsal cortex (ICd); and MGm receives substantial input from both ICc (~40%) and IC lateral cortex (~40%). Each MG subdivision receives additional input (up to 32%) from non-dominant IC subdivisions, suggesting cross-talk between the pathways. The proportion of GABAergic cells in each pathway depended on the MG subdivision. GABAergic cells formed ~20% of IC inputs to MGv or MGm, ~11% of inputs to MGd, and 4% of inputs to MGsg. Thus, non-GABAergic (i.e., glutamatergic) cells are most numerous in each pathway with GABAergic cells contributing to different extents. Despite smaller numbers of GABAergic cells, their distributions across IC subdivisions mimicked the parallel pathways. Projections outside the dominant pathways suggest opportunities for excitatory and inhibitory crosstalk. The results demonstrate parallel tectothalamic pathways in guinea pigs and suggest numerous opportunities for excitatory and inhibitory interactions within and between pathways

    Highly sensitive quantitative PCR for the detection and differentiation of Pseudogymnoascus destructans and other Pseudogymnoascus species

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    White-nose syndrome is a fungal disease that has decimated bat populations across eastern North America. Identification of the etiologic agent, Pseudogymnoascus destructans (formerly Geomyces destructans), in environmental samples is essential to proposed management plans. A major challenge is the presence of closely related species, which are ubiquitous in many soils and cave sediments and often present in high abundance. We present a dual-probe real-time quantitative PCR assay capable of detecting and differentiating P. destructans from closely related fungi in environmental samples from North America. The assay, based on a single nucleotide polymorphism (SNP) specific to P. destructans, is capable of rapid low-level detection from various sampling media, including sediment, fecal samples, wing biopsy specimens, and skin swabs. This method is a highly sensitive, high-throughput method for identifying P. destructans, other Pseudogymnoascus spp., and Geomyces spp. in the environment, providing a fundamental component of research and risk assessment for addressing this disease, as well as other ecological and mycological work on related fungi

    Tuberculosis in the Torres Strait: the lady doth test too much

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    Introduction: Smear-positive pulmonary tuberculosis (PTB) requires rapid diagnosis and treatment to prevent ongoing transmission. Collection of two sputum specimens is considered the minimum requirement for the diagnosis of PTB but current guidelines in the Torres Strait Islands, Australia, recommend three sputum specimens; this frequently delays treatment initiation. Methods: A retrospective study was performed to ascertain the diagnostic yield of sputum specimens collected in the Torres Strait Islands. The study assessed demographics and characteristics of all PTB cases diagnosed between 2000 and 2018, and assessed the diagnostic yield in 143 patients from whom at least three sputum specimens had been collected prior to treatment commencement. Incremental and cumulative yield was calculated for each sputum specimen. Data were further analysed using binary logistic regression to examine the association between selected characteristics and a smear-positive acid-fast bacilli (AFB) result. Results: Overall, AFB was detected from the first or second sputum specimen in 97 of 101 PTB cases that were sputum smear positive. A smear-positive result was more common (odds ratio 2.84, 95% confidence interval 1.08–7.46) for Papua New Guinea nationals compared to Australian born patients. Of the 429 samples collected, 76 (18%) were of poor quality and the association between poor quality specimens and smear-negative results was significant (p<0.01). Among sputum smear-negative cases, 5/42= (12%) had three consecutive poor quality specimens. The most common collection modality in adults was voluntary expectoration; done in 391/429 (91%) of all specimens collected. Alternative specimen collection methods were mainly used in children; induced sputum 1/429 (0.2%), gastric aspirate 26/429 (6%) and nasopharyngeal aspirate 7/429 (1.6%). Errors with labelling, packaging and transportation occurred in 44 specimens from 15 patients. Conclusion: Two good quality specimens ensure adequate diagnostic yield for PTB and a third specimen should only be collected from patients with two negative specimens who have persistent symptoms. Ideally, decentralised Xpert Ultra¼ should be the frontline diagnostic test in remote settings, especially in settings like the Torres Strait Islands with high rates of drugresistant TB

    Genomics reveals historic and contemporary transmission dynamics of a bacterial disease among wildlife and livestock

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    Whole-genome sequencing has provided fundamental insights into infectious disease epidemiology, but has rarely been used for examining transmission dynamics of a bacterial pathogen in wildlife. In the Greater Yellowstone Ecosystem (GYE), outbreaks of brucellosis have increased in cattle along with rising seroprevalence in elk. Here we use a genomic approach to examine Brucella abortus evolution, cross-species transmission and spatial spread in the GYE. We find that brucellosis was introduced into wildlife in this region at least five times. The diffusion rate varies among Brucella lineages (∌3 to 8 km per year) and over time. We also estimate 12 host transitions from bison to elk, and 5 from elk to bison. Our results support the notion that free-ranging elk are currently a self-sustaining brucellosis reservoir and the source of livestock infections, and that control measures in bison are unlikely to affect the dynamics of unrelated strains circulating in nearby elk populations

    Comparing the Effects of Two Tillage Operations on Beneficial Epigeal Arthropod Communities and Their Associated Ecosystem Services in Sugar Beets

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    Published ArticleBeneficial arthropods provide important ecosystem services in terms of arthropod pest and weed management, but these services can be adversely affected by farming practices such as tillage. This study investigated the impact of two tillage operations (zone tillage and moldboard plow) on the activity density of several beneficial, epigeal arthropod taxa, and postdispersal weed seed and prey removal in sugar beet agroecosystems. In addition, four omnivorous ground beetle species were selected for a weed-seed choice feeding assay, whereas a single species was selected for a weed-seed age preference assay. Ground beetles were the most commonly collected taxon (via pitfall sampling), with only a few dominant species. Tillage operation did not affect ground beetle activity density; however, spider, centipede, and rove beetle activity densities were higher in the reduced-tillage treatment. Live prey consumption was similar between tillage practices, with more prey consumed during nocturnal hours. More weed seeds were consumed in the reduced-tillage treatment, whereas weed-seed preference differed between the four weed species tested [Setaria pumila (Poir.) Roem. & Schult., Echinochloa crus-galli (L.), Kochia scoparia (L.), and Chenopodium album (L.)]. In the weed-seed choice feeding assay, significantly more broad-leaf weed seeds (C. album and K. scoparia) were consumed compared with grassy weed seeds (E. crus-galli and S. pumila). No preference for seed age was detected for E. crus-galli, but Harpalus pensylvanicus (De Geer) preferred old C. album seeds over fresh seeds. Zone tillage is compatible with ecosystem services, providing critical habitat within agricultural ecosystems needed to conserve beneficial, edaphic arthropods

    Rapid, energy-efficient synthesis of the layered carbide, Al<sub>4</sub>C<sub>3</sub>

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    The phase-pure binary aluminium carbide, Al4C3 can be synthesised in vacuo from the elements in 30 minutes via microwave heating in a multimode cavity reactor. The success of the reaction is dependent on the use of finely divided aluminium and graphite starting materials, both of which couple effectively to the microwave field. The yellow-brown powder product was characterised by powder X-ray diffraction, scanning electron microscopy/energy dispersive X-ray spectroscopy thermogravimetric-differential thermal analysis and Raman spectroscopy. Powders were composed of hexagonal single crystallites tens of microns in diameter (rhombohedral space group R[3 with combining macron]m; Z = 3; a = 3.33813(5) Å, c = 25.0021(4) Å) and were stable to 1000 °C in air, argon and nitrogen. Equivalent microwave reactions of the elements in air led to the formation of the oxycarbide phases Al2OC and Al4O4C
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