3,004 research outputs found

    Study to develop improved methods to detect leakage in fluid systems, phase 3

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    Research was undertaken to design and fabricate a prototype flight weight ultrasonic contact sensor leak detection system and to perform the necessary testing to collect enough data to establish design parameters and develop necessary baseline operating characteristics. The prototype system consists of five channels and is capable for monitoring frequencies from 1 KHz to 110 KHz

    Cognition in Rodents

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    Cognition is a loosely defined term with divergent meanings in different disciplines and species. In human psychology, ‘cognition’ is often used in reference to concepts such as ‘mind’ or ‘higher mental functions’. However, in more general terms, ‘cognition’ is regularly used to refer to all manner of information organization by the brain: from collection, to processing, to storage and recognition or recall. Whereas ‘cognition’ would seem to permeate all mental functions, including subjective perception and innate responses, ‘cognitive ability’ has a slightly more specific connotation – something more akin to intelligence or information-processing ability. Thus, ‘cognition’ deals with mental process structure and ‘cognitive abilities’ with natural variations impinging upon functioning at the higher end of that structure. Although the term ‘cognition’ sometimes subsumes or substitutes ‘cognitive ability’ in the literature, understanding this methodological distinction allows us to read across the two fields without the misunderstandings that classical cognitive psychologists have sometimes shown for cognitive ability research

    The polyphyly of Plasmodium: Comprehensive phylogenetic analyses of the malaria parasites (Order Haemosporida) reveal widespread taxonomic conflict

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    © 2018 The Authors. The evolutionary relationships among the apicomplexan blood pathogens known as the malaria parasites (order Haemosporida), some of which infect nearly 200 million humans each year, has remained a vexing phylogenetic problem due to limitations in taxon sampling, character sampling and the extreme nucleotide base composition biases that are characteristic of this clade. Previous phylogenetic work on the malaria parasites has often lacked sufficient representation of the broad taxonomic diversity within the Haemosporida or the multi-locus sequence data needed to resolve deep evolutionary relationships, rendering our understanding of haemosporidian lifehistory evolution and the origin of the human malaria parasites incomplete. Here we present the most comprehensive phylogenetic analysis of the malaria parasites conducted to date, using samples from a broad diversity of vertebrate hosts that includes numerous enigmatic and poorly known haemosporidian lineages in addition to genome-wide multi-locus sequence data. We find that if base composition differences were corrected for during phylogenetic analysis, we recovered a well-supported topology indicating that the evolutionary history of the malaria parasites was characterized by a complex series of transitions in life-history strategies and host usage. Notably we find that Plasmodium, the malaria parasite genus that includes the species of human medical concern, is polyphyletic with the life-history traits characteristic of this genus having evolved in a dynamic manner across the phylogeny. We find support for multiple instances of gain and loss of asexual proliferation in host blood cells and production of haemozoin pigment, two traits that have been used for taxonomic classification as well as considered to be important factors for parasite virulence and used as drug targets. Lastly, our analysis illustrates the need for a widespread reassessment of malaria parasite taxonomy

    A biophysical model of prokaryotic diversity in geothermal hot springs

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    Recent field investigations of photosynthetic bacteria living in geothermal hot spring environments have revealed surprisingly complex ecosystems, with an unexpected level of genetic diversity. One case of particular interest involves the distribution along hot spring thermal gradients of genetically distinct bacterial strains that differ in their preferred temperatures for reproduction and photosynthesis. In such systems, a single variable, temperature, defines the relevant environmental variation. In spite of this, each region along the thermal gradient exhibits multiple strains of photosynthetic bacteria adapted to several distinct thermal optima, rather than the expected single thermal strain adapted to the local environmental temperature. Here we analyze microbiology data from several ecological studies to show that the thermal distribution field data exhibit several universal features independent of location and specific bacterial strain. These include the distribution of optimal temperatures of different thermal strains and the functional dependence of the net population density on temperature. Further, we present a simple population dynamics model of these systems that is highly constrained by biophysical data and by physical features of the environment. This model can explain in detail the observed diversity of different strains of the photosynthetic bacteria. It also reproduces the observed thermal population distributions, as well as certain features of population dynamics observed in laboratory studies of the same organisms

    Perioperative Cerebral Microbleeds After Adult Cardiac Surgery.

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    Background and Purpose- Cerebral microbleeds (CMBs) have been observed using magnetic resonance imaging in patients with cardiovascular risk factors, cognitive deterioration, small vessel disease, and dementia. They are a well-known consequence of cerebral amyloid angiopathy, chronic hypertension, and diffuse axonal injury, among other causes. However, the frequency and location of new CMBs postadult cardiac surgery, in association with cognition and perioperative risk factors, have yet to be studied. Methods- Pre- and postsurgery magnetic resonance susceptibility-weighted images and neuropsychological tests were analyzed from a total of 75 patients undergoing cardiac surgery (70 men; mean age, 63±10 years). CMBs were identified by a neuroradiologist blinded to clinical details who independently assessed the presence and location of CMBs using standardized criteria. Results- New CMBs were identified in 76% of patients after cardiac surgery. The majority of new CMBs were located in the frontal lobe (46%) followed by the parietal lobe (15%), cerebellum (13%), occipital lobe (12%), and temporal lobe (8%). Patients with new CMBs typically began with a higher prevalence of preexisting CMBs ( P=0.02). New CMBs were associated with longer cardiopulmonary bypass times ( P=0.003), and there was a borderline association with lower percentage hematocrit ( P=0.04). Logistic regression analysis suggested a ≈2% increase in the odds of acquiring new CMBs during cardiac surgery for every minute of bypass time (odds ratio, 1.02; 95% CI, 1.00-1.05; P=0.04). Postoperative neuropsychological decline was observed in 44% of patients and seemed to be unrelated to new CMBs. Conclusions- New CMBs identified using susceptibility-weighted images were found in 76% of patients who underwent cardiac surgery. CMBs were globally distributed with the highest numbers in the frontal and parietal lobes. Our regression analysis indicated that length of cardiopulmonary bypass time and lowered hematocrit may be significant predictors for new CMBs after cardiac surgery. Clinical Trial Registration- URL: http://www.isrctn.com . Unique identifier: 66022965

    Suited for Success? : Suits, Status, and Hybrid Masculinity

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    This document is the Accepted Manuscript version. The final, definitive version of this paper has been published in Men and Masculinities, March 2017, doi: https://doi.org/10.1177/1097184X17696193, published by SAGE Publishing, All rights reserved.This article analyzes the sartorial biographies of four Canadian men to explore how the suit is understood and embodied in everyday life. Each of these men varied in their subject positions—body shape, ethnicity, age, and gender identity—which allowed us to look at the influence of men’s intersectional identities on their relationship with their suits. The men in our research all understood the suit according to its most common representation in popular culture: a symbol of hegemonic masculinity. While they wore the suit to embody hegemonic masculine configurations of practice—power, status, and rationality—most of these men were simultaneously marginalized by the gender hierarchy. We explain this disjuncture by using the concept of hybrid masculinity and illustrate that changes in the style of hegemonic masculinity leave its substance intact. Our findings expand thinking about hybrid masculinity by revealing the ways subordinated masculinities appropriate and reinforce hegemonic masculinity.Peer reviewe

    Soundscape Optimization in Nursing Homes Through Raising Awareness in Nursing Staff With MoSART+

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    Introduction: Soundscapes in nursing homes are often suboptimal for residents. This can cause them feeling anxious and unsafe, or develop behavioral and psychological problems. Residents with dementia cannot adapt nursing home environments to their needs due to cognitive and physical limitations. It is up to the staff of psycho-geriatric wards to improve the soundscape. We evaluated the effect of the sound awareness intervention Mobile Soundscape Appraisal and Recording Technology (MoSART+) on soundscapes in nursing homes. Methods: The MoSART+ intervention was carried out in four nursing homes and took three months in each home. The MoSART+ intervention involved training ambassadors, assessing the soundscape with the MoSART application by the nursing staff to raise their sound awareness on random time points, discussing the measurements, and implementing micro-interventions. Soundscapes were assessed from 0 to 100 on four attributes: pleasantness, eventfulness, complexity, and range of affordances. Based on these scores, soundscapes were classified in four dimensions: calm, lively, boring, and chaotic. Nursing staff graded the environment on a scale of 0 to 10. T-test and Z-tests were used to analyze data. Results: Staff recorded 1882 measurements with the MoSART app. "People," "music, TV, and radio," and "machines and appliances" were the most prevalent sound sources before and after the implementation of micro-interventions. Post-implementation of micro-interventions, soundscapes were pleasant (median 69.0; IQR 54.0-81.0), of low complexity (33.0; 18.0-47.0), uneventful (27.0; 14.0-46.5), and gave moderate affordances (50.0; 35.0-67.0). Changes in attributes were statistically significant (p < 0.01). The proportion of the dimension calm increased (z = 12.7, p < 0.01), the proportion of chaotic decreased (z = 15.0, p < 0.01), and the proportion of lively decreased not statically significant (z = 0.68, p = 0.79). The proportion of boring was unchanged. The proportion of grades ≥6 increased after implementation of the micro-interventions (z = 15.3, p < 0.01). The micro-interventions focused on removing or reducing disturbing sounds and were unique for each nursing home. Discussion: The MoSART+ intervention resulted in a statistically significantly improvement of soundscapes, and more favorable evaluations of the nursing staff. The intervention empowered staff to adapt soundscapes. Nursing homes can improve soundscapes by raising sound awareness among staff. Trial Registration: Netherlands National Trial Register (NL6831)

    Sounds in nursing homes and their effect on health in dementia:A systematic review

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    OBJECTIVES: Nursing home residents with dementia are sensitive to detrimental auditory environments. This paper presents the first literature review of empirical research investigating (1) the (perceived) intensity and sources of sounds in nursing homes, and (2) the influence of sounds on health of residents with dementia and staff. DESIGN: A systematic review was conducted in PubMed, Web of Science and Scopus. Study quality was assessed with the Mixed Methods Appraisal Tool. We used a narrative approach to present the results. RESULTS: We included 35 studies. Nine studies investigated sound intensity and reported high noise intensity with an average of 55-68 dB(A) (during daytime). In four studies about sound sources, human voices and electronic devices were the most dominant sources. Five cross-sectional studies focused on music interventions and reported positives effects on agitated behaviors. Four randomized controlled trials tested noise reduction as part of an intervention. In two studies, high-intensity sounds were associated with decreased nighttime sleep and increased agitation. The third study found an association between music and less agitation compared to other stimuli. The fourth study did not find an effect of noise on agitation. Two studies reported that a noisy environment had negative effects on staff. CONCLUSIONS: The need for appropriate auditory environments that are responsive to residents' cognitive abilities and functioning is not yet recognized widely. Future research needs to place greater emphasis on intervention-based and longitudinal study design

    Population-Level Associations between Preschool Vulnerability and Grade-Four Basic Skills

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    Background: This is a predictive validity study examining the extent to which developmental vulnerability at kindergarten entry (as measured by the Early Development Instrument, EDI) is associated with children’s basic skills in 4th grade (as measured by the Foundation Skills Assessment, FSA). Methodology/Principal Findings: Relative risk analysis was performed on a large database linking individual-level EDI ratings to the scores the same children obtained on a provincial assessment of academic skills (FSA – Foundation Skills Assessment) four years later. We found that early vulnerability in kindergarten is associated with the basic skills that underlie populations of children’s academic achievement in reading, writing and math, indicating that the Early Development Instrument permits to predict achievement-related skills four years in advance. Conclusions/Significance: The EDI can be used to predict children’s educational trends at the population level and can help select early prevention and intervention programs targeting pre-school populations at minimum cost
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