1,136 research outputs found

    Self-welding in space: aerospace safety survey

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    Switch rates vary due to expected payoff but not due to individual risk tendency.

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    When switching between different tasks, the initiation of task switches may depend on task characteristics (difficulty, salient cues, etc.) or reasons within the person performing the task (decisions, behavioral variability, etc.). The reasons for variance in switching strategies, especially in paradigms where participants are free to choose the order of tasks and the amount of switching between tasks, are not well researched. In this study, we follow up the recent discussion that variance in switching strategies might be partly explained by the characteristics of the person fulfilling the task. We examined whether risk tendency and impulsiveness differentiate individuals in their response (i.e., switch rates and time spent on tasks) to different task characteristics on a tracking-while-typing paradigm. In detail, we manipulated two aspects of loss prospect (i.e., "payoff" as the amount of points that could be lost when tracking was unattended for too long, and "cursor speed" determining the likelihood of such a loss occurring). To account for between-subject variance and within-subject variability in the data, we employed linear mixed effect analyses following the model selection procedure (Bates, Kliegl, et al., 2015). Besides, we tested whether risk tendency can be transformed into a decision parameter which could predict switching strategies when being computationally modelled. We transferred decision parameters from the Decision Field Theory to model "switching thresholds" for each individual. Results show that neither risk tendency nor impulsiveness explain between-subject variance in the paradigm, nonetheless linear mixed-effects models confirmed that within-subject variability plays a significant role for interpreting dual-task data. Our computational model yielded a good model fit, suggesting that the use of a decision threshold parameter for switching may serve as an alternative means to classify different strategies in task switching. [Abstract copyright: Copyright © 2022. Published by Elsevier B.V.

    Obstructive sleep apnea screening with breathing sounds and respiratory effort: a multimodal deep learning approach

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    Obstructive sleep apnea (OSA) is a chronic and prevalent condition with well-established comorbidities. Due to limited diagnostic resources and high cost, a significant OSA population lives undiagnosed, and accurate and low-cost methods to screen for OSA are needed. We propose a novel screening method based on breathing sounds recorded with a smartphone and respiratory effort. Whole night recordings are divided into 30-s segments, each of which is classified for the presence or absence of OSA events by a multimodal deep neural network. Data fusion techniques were investigated and evaluated based on the apnea-hypopnea index estimated from whole night recordings. Real-world recordings made during home sleep apnea testing from 103 participants were used to develop and evaluate the proposed system. The late fusion system achieved the best sensitivity and specificity when screening for severe OSA, at 0.93 and 0.92, respectively. This offers the prospect of inexpensive OSA screening at home

    The effect of chirality phenotype and genotype on the fecundity and viability of Partula suturalis and Lymnaea stagnalis: Implications for the evolution of sinistral snails

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    Why are sinistral snails so rare? Two main hypotheses are that selection acts against the establishment of new coiling morphs, because dextral and sinistral snails have trouble mating, or else a developmental constraint prevents the establishment of sinistrals. We therefore used an isolate of the snail Lymnaea stagnalis, in which sinistrals are rare, and populations of Partula suturalis, in which sinistrals are common, as well as a mathematical model, to understand the circumstances by which new morphs evolve. The main finding is that the sinistral genotype is associated with reduced egg viability in L. stagnalis, but in P. suturalis individuals of sinistral and dextral genotype appear equally fecund, implying a lack of a constraint. As positive frequency-dependent selection against the rare chiral morph in P. suturalis also operates over a narrow range (< 3%), the results suggest a model for chiral evolution in snails in which weak positive frequency-dependent selection may be overcome by a negative frequency-dependent selection, such as reproductive character displacement. In snails, there is not always a developmental constraint. As the direction of cleavage, and thus the directional asymmetry of the entire body, does not generally vary in other Spiralia (annelids, echiurans, vestimentiferans, sipunculids and nemerteans), it remains an open question as to whether this is because of a constraint and/or because most taxa do not have a conspicuous external asymmetry (like a shell) upon which selection can act

    Beyond opioid prescribing: Evaluation of a substance use disorder curriculum for OBGYN residents

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    Objective Amidst the current opioid crisis, there is a need for better integration of substance use disorder screening and treatment across specialties. However, there is no consensus regarding how to best instruct OBGYN trainees in the clinical skills related to opioid and other substance use disorders (SUD). Study objectives were (1) to assess the effectiveness a SUD curriculum to improve self-reported competence among OBGYN residents and (2) to explore its effectiveness to improve attending evaluations of residents clinical skills as well as its feasibility and acceptability from the resident perspective. Methods A pilot 3-session curriculum was developed and adapted to SUD screening and treatment which included readings, didactics, and supervised outpatient clinical experiences for OBGYN post-graduate year 1 (PGY-1) residents rotating through an integrated OBGYNSUD clinic. Eighteen residents completed pre and post clinical skills self-Assessments (SUD screening, counseling, referring, Motivational Interviewing) using an adapted Zwisch Rating Scale (range 1 5). Scores were compared between time points using paired t-Tests. Subsamples also (a) were evaluated by the attending on three relevant Accreditation Council for Graduate Medical Education Milestones (ACGME) milestone sets using the web-based feedback program, myTIPreport (n = 10) and (b) completed a qualitative interview (n = 4). Results All PGY-1s (18/18) across three academic years completed the 3-session SUD curriculum. Clinical skill self-Assessments improved significantly in all areas [SUD Screening (2.44 (0.98) vs 3.56 (0.62), p = 0.01); Counseling (1.81 (0.71) vs 3.56 (0.51), p = .01; Referring (2.03 (0.74) vs 3.17 (0.71), p = .01; Motivational Interviewing (1.94 (1.06) vs 3.33 (0.69), p = .01)]. Milestone set levels assigned by attending evaluations (n = 10) also improved. Qualitative data (n = 4) revealed high acceptability; all curriculum components were viewed positively, and feedback was provided (e.g., desire for more patient exposures). Conclusion A pilot SUD curriculum tailored for OBGYN PGY-1 residents that goes beyond opioid prescribing to encompass SUD management is feasible, acceptable and likely effective at improving SUD core clinical skills

    Final report on impact of catchment scale processes and climate change on cause-effect and recovery-chains

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    Catchment wide integrated basin management requires knowledge on cause-effect and recovery chains within water bodies as well as on the interactions between water bodies and categories. In the WISER WP6.4 recovery processes in rivers, lakes and estuarine and coastal waters were evaluated. The major objectives were: - to analyse and compare (cause-effect and) recovery chains within water categories based on processes and structural and functional features; - to detect commonalities among different chains in different water categories ( to compare recovery chains between water categories); - to link recovery chains to over-arching biological processes and global change; - to develop a method to combine recovery effects in a summarising ‘catchment’ metric. The main stressors studied to reach these objectives were acidification, eutrophication and hydromorphological changes

    Can lepton flavor violating interactions explain the LSND results?

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    If the atmospheric and the solar neutrino problem are both explained by neutrino oscillations, and if there are only three light neutrinos, then all mass-squared differences between the neutrinos are known. In such a case, existing terrestrial neutrino oscillation experiments cannot be significantly affected by neutrino oscillations, but, in principle there could be an anomaly in the neutrino flux due to new neutrino interactions. We discuss how a non-standard muon decay μ+→e+νˉeνℓ\mu^+ \to e^+ \bar\nu_e \nu_\ell would modify the neutrino production processes of these experiments. Since SU(2)LSU(2)_L violation is small for New Physics above the weak scale one can use related flavor-violating charged lepton processes to constrain these decays in a model independent way. We show that the upper bounds on μ→3e\mu \to 3e, muonium-antimuonium conversion and τ→μee\tau \to \mu e e rule out any observable effect for the present experiments due to μ+→e+νˉeνℓ\mu^+ \to e^+ \bar\nu_e \nu_\ell for ℓ=e,μ,τ\ell=e,\mu,\tau, respectively. Applying similar arguments to flavor-changing semi-leptonic reactions we exclude the possibility that the "oscillation signals" observed at LSND are due to flavor-changing interactions that conserve total lepton number.Comment: 21 pages, 6 figures, Latex; minor correction

    Iodine binding to humic acid

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    The rate of reactions between humic acid (HA) and iodide (I-) and iodate (IO3-) have been investigated in suspensions spiked with 129I at concentrations of 22, 44 and 88 µg L-1 and stored at 10oC. Changes in the speciation of 129I-, 129IO3- and mixed (129I-+129IO3-) spikes were monitored over 77 days using liquid chromatography inductively coupled plasma mass spectrometry (LC-ICP-MS). In suspensions spiked with 129I- 25% of the added I- was transformed into organic iodine (Org-129I) within 77 days and there was no evidence of 129IO3- formation. By contrast, rapid loss of 129IO3- and increase in both 129I- and Org-129I was observed in 129IO3--spiked suspensions. However, the rate of Org-129I production was greater in mixed systems compared to 129IO3--spiked suspensions with the same total 129I concentration, possibly indicating IO3-—I- redox coupling. Size exclusion chromatography (SEC) demonstrated that Org-129I was present in both high and low molecular weight fractions of the HA although a slight preference to bond with the lower molecular weight fractions was observed indicating that, after 77 days, the spiked isotope had not fully mixed with the native 127I pool. Iodine transformations were modelled using first order rate equations and fitted rate coefficients determined. However, extrapolation of the model to 250 days indicated that a pseudo-steady state would be attained after ~ 200 days but that the proportion of 129I incorporated into HA was less than that of 127I indicating the presence of a recalcitrant pool of 127I that was unavailable for isotopic mixing

    Magnetic ground state of the two isostructual polymeric quantum magnets [Cu(HF2)(pyrazine)2]SbF6 and [Co(HF2)(pyrazine)2]SbF6 investigated with neutron powder diffraction

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    The magnetic ground state of two isostructural coordination polymers, (i) the quasi-two-dimensional S=1/2 square-lattice antiferromagnet [Cu(HF2)(pyrazine)2]SbF6 and (ii) a related compound [Co(HF2)(pyrazine)2]SbF6, was examined with neutron powder diffraction measurements. We find that the ordered moments of the Heisenberg S=1/2 Cu(II) ions in [Cu(HF2)(pyrazine)2]SbF6 are 0.6(1)μb, while the ordered moments for the Co(II) ions in [Co(HF2)(pyrazine)2]SbF6 are 3.02(6)μb. For Cu(II), this reduced moment indicates the presence of quantum fluctuations below the ordering temperature. We show from heat capacity and electron spin resonance measurements that due to the crystal electric field splitting of the S=3/2 Co(II) ions in [Co(HF2)(pyrazine)2]SbF6, this isostructual polymer also behaves as an effective spin-half magnet at low temperatures. The Co moments in [Co(HF2)(pyrazine)2]SbF6 show strong easy-axis anisotropy, neutron diffraction data, which do not support the presence of quantum fluctuations in the ground state, and heat capacity data, which are consistent with 2D or close to 3D spatial exchange anisotropy

    Evolution of whole-body enantiomorphy in the tree snail genus Amphidromus

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    Diverse animals exhibit left–right asymmetry in development. However, no example of dimorphism for the left–right polarity of development (whole-body enantiomorphy) is known to persist within natural populations. In snails, whole-body enantiomorphs have repeatedly evolved as separate species. Within populations, however, snails are not expected to exhibit enantiomorphy, because of selection against the less common morph resulting from mating disadvantage. Here we present a unique example of evolutionarily stable whole-body enantiomorphy in snails. Our molecular phylogeny of South-east Asian tree snails in the genus Amphidromus indicates that enantiomorphy has likely persisted as the ancestral state over a million generations. Enantiomorphs have continuously coexisted in every population surveyed spanning a period of 10 years. Our results indicate that whole-body enantiomorphy is maintained within populations opposing the rule of directional asymmetry in animals. This study implicates the need for explicit approaches to disclosure of a maintenance mechanism and conservation of the genus
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