194 research outputs found

    Individual Movement Rates Are Sufficient To Determine And Maintain Dynamic Spatial Positioning Within UCA Pugilator Herds

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    Spatial location within aggregations (i.e. periphery, central) is of biological significance to gregarious animals. Because these positions are a potential consequence of consistent individual behavioral differences, or personality, a better understanding of potential mechanisms concerning personality is central to predicting an individuals’ location. To determine the effects of individual personality on the dynamic spatial positioning of Uca pugilator while herding, field data collection and agent-based modeling were employed. Individuals were assayed to establish their personalities and returned to the field for observation as a means of identifying location preference within selfish herds. There was a significant difference between the extreme personalities and the proportion of time spent on the edge of the herd. The active individuals were at the periphery ~50% more of the time than less active individuals. An individual-based model qualitatively replicated these field results by applying the mechanism of activity level as an indicator of individual personality. This suggests that differences in personality-dependent movement are sufficient to explain the spatial positioning of individuals within selfish herds. This study enhances our understanding of the possible mechanisms that govern group movement, and has implications for modeling population dynamics that can be influenced by individual personality

    Interaction of feel system and flight control system dynamics on lateral flying qualities

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    An experimental investigation of the influence of lateral feel system characteristics on fighter aircraft roll flying qualities was conducted using the variable stability USAF NT-33. Forty-two evaluation flights were flown by three engineering test pilots. The investigation utilized the power approach, visual landing task and up-and-away tasks including formation, gun tracking, and computer-generated compensatory attitude tracking tasks displayed on the Head-Up Display. Experimental variations included the feel system frequency, force-deflection gradient, control system command type (force or position input command), aircraft roll mode time constant, control system prefilter frequency, and control system time delay. The primary data were task performance records and evaluation pilot comments and ratings using the Cooper-Harper scale. The data highlight the unique and powerful effect of the feel system of flying qualities. The data show that the feel system is not 'equivalent' in flying qualities influence to analogous control system elements. A lower limit of allowable feel system frequency appears warranted to ensure good lateral flying qualities. Flying qualities criteria should most properly treat the feel system dynamic influence separately from the control system, since the input and output of this dynamic element is apparent to the pilot and thus, does not produce a 'hidden' effect

    Assessing the Competitive Advantage of Carbonic Anhydrase in Estuarine Microalgae Through Removed Enzymatic Activity

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    Carbon concentrating mechanisms (CCMs) are used by photoautotrophs to overcome possible limitations in carbon acquisition but the competitive strategies and efficiencies of these mechanisms among photosynthesizers can be variable. The diversity in carbon acquisition abilities establishes the potential for alterations in community structure with shifting carbon concentrations. Given the role of phytoplankton and benthic microalgae (BMA) in the trophodynamics of estuaries, understanding the mechanisms of carbon acquisition in these systems is important in predicting how primary productivity and nutrient cycling might change in response to increasing concentrations of atmospheric CO2. Our approach to investigate whether induced carbon limitation would show predictable shifts in microalgal community structure and production was conducted through the inhibition of an enzyme used in CCMs, carbonic anhydrase (CA). CA catalyzes the rates of interconversion between CO2 and HCO3- to facilitate transport of inorganic carbon into the cell and trap that carbon there. Although CA has the potential to help mitigate increasing CO2 levels in the atmosphere, evaluations on how different species use CA and the physiological roles it may perform in microalgae are needed. We show phytoplankton communities from different environments are altered when a CA inhibitor (i.e. ethoxyzolamide, EZ) is present and CA activity is suppressed. Diatoms remained the dominant taxonomic group in all samples following a 3-day inhibition of CA but there were lower-level community shifts. These shifts in community structure suggest that phytoplankton composition is affected by carbon acquisition using CA, and some diatom genera may depend on the competitive advantage of this enzyme for their CCMs to maintain high abundances in estuarine environments. Most of the diatom genera had strong growth limitation and cell mortality without active CA, however, some pennate diatoms like Cylindrotheca persisted with positive growth rates. All four of our cultured diatoms experienced a decrease in gross primary production (GPP) and relative electron transport rate at high irradiance levels indicating that some other physiological traits were giving Cylindrotheca the competitive benefit. Decreased GPP was similarly observed in the BMA communities as well with CA inhibition. However, this limitation in carbon acquisition drove motile benthic microalgae to make use of a smaller vertical profile closer to the sediment surface rather than exhibit the mortality seen in most of our cultured diatom genera. Predicting marine microalgal responses to changes in CO2 availability requires further characterization of other physiological traits across a higher diversity of growth conditions and taxa. Our research demonstrates that there can be wide variability in carbon acquisition strategies within the diatom genera and that the competitive advantage provided by CA and efficiency of their CCMs may be dependent on the environment’s carbon availability. Continued mechanistic approaches are needed to recognize the impacts of CA activity on microalgal communities with respect to their assemblage, cell-size fractions, primary production rates, and physiological performance

    QT Interval Prolongation and Torsade De Pointes in Patients with COVID-19 treated with Hydroxychloroquine/Azithromycin

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    Background: There is no known effective therapy for patients with COVID-19. Initial reports suggesting the potential benefit of Hydroxychloroquine/Azithromycin (HY/AZ) have resulted in massive adoption of this combination worldwide. However, while the true efficacy of this regimen is unknown, initial reports have raised concerns regarding the potential risk of QT prolongation and induction of torsade de pointes (TdP). Objective: to assess the change in QTc interval and arrhythmic events in patients with COVID-19 treated with HY/AZ METHODS: This is a retrospective study of 251 patients from two centers, diagnosed with COVID-19 and treated with HY/AZ. We reviewed ECG tracings from baseline and until 3 days after completion of therapy to determine the progression of QTc and incidence of arrhythmia and mortality. Results: QTc prolonged in parallel with increasing drug exposure and incompletely shortened after its completion. Extreme new QTc prolongation to > 500 ms, a known marker of high risk for TdP had developed in 23% of patients. One patient developed polymorphic ventricular tachycardia (VT) suspected as TdP, requiring emergent cardioversion. Seven patients required premature termination of therapy. The baseline QTc of patients exhibiting extreme QTc prolongation was normal. Conclusion: The combination of HY/AZ significantly prolongs the QTc in patients with COVID-19. This prolongation may be responsible for life threating arrhythmia in the form of TdP. This risk mandates careful consideration of HY/AZ therapy in lights of its unproven efficacy. Strict QTc monitoring should be performed if the regimen is given

    Molecular Characterization of the Tumor Suppressor Candidate 5 Gene: Regulation by PPARγ and Identification of TUSC5 Coding Variants in Lean and Obese Humans

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    Tumor suppressor candidate 5 (TUSC5) is a gene expressed abundantly in white adipose tissue (WAT), brown adipose tissue (BAT), and peripheral afferent neurons. Strong adipocyte expression and increased expression following peroxisome proliferator activated receptor γ (PPARγ) agonist treatment of 3T3-L1 adipocytes suggested a role for Tusc5 in fat cell proliferation and/or metabolism. However, the regulation of Tusc5 in WAT and its potential association with obesity phenotypes remain unclear. We tested the hypothesis that the TUSC5 gene is a bona fide PPARγ target and evaluated whether its WAT expression or single-nucleotide polymorphisms (SNPs) in the TUSC5 coding region are associated with human obesity. Induction of Tusc5 mRNA levels in 3T3-L1 adipocytes by troglitazone and GW1929 followed a dose-response consistent with these agents' binding affinities for PPARγ. Chromatin immunoprecipitation (ChIP) experiments confirmed that PPARγ protein binds a ∼ −1.1 kb promotor sequence of murine TUSC5 transiently during 3T3-L1 adipogenesis, concurrent with histone H3 acetylation. No change in Tusc5 mRNA or protein levels was evident in type 2 diabetic patients treated with pioglitazone. Tusc5 expression was not induced appreciably in liver preparations overexpressing PPARs, suggesting that tissue-specific factors regulate PPARγ responsiveness of the TUSC5 gene. Finally, we observed no differences in Tusc5 WAT expression or prevalence of coding region SNPs in lean versus obese human subjects. These studies firmly establish the murine TUSC5 gene locus as a PPARγ target, but the significance of Tusc5 in obesity phenotypes or in the pharmacologic actions of PPARγ agonists in humans remains equivocal

    The Dispanins: A Novel Gene Family of Ancient Origin That Contains 14 Human Members

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    The Interferon induced transmembrane proteins (IFITM) are a family of transmembrane proteins that is known to inhibit cell invasion of viruses such as HIV-1 and influenza. We show that the IFITM genes are a subfamily in a larger family of transmembrane (TM) proteins that we call Dispanins, which refers to a common 2TM structure. We mined the Dispanins in 36 eukaryotic species, covering all major eukaryotic groups, and investigated their evolutionary history using Bayesian and maximum likelihood approaches to infer a phylogenetic tree. We identified ten human genes that together with the known IFITM genes form the Dispanin family. We show that the Dispanins first emerged in eukaryotes in a common ancestor of choanoflagellates and metazoa, and that the family later expanded in vertebrates where it forms four subfamilies (A–D). Interestingly, we also find that the family is found in several different phyla of bacteria and propose that it was horizontally transferred to eukaryotes from bacteria in the common ancestor of choanoflagellates and metazoa. The bacterial and eukaryotic sequences have a considerably conserved protein structure. In conclusion, we introduce a novel family, the Dispanins, together with a nomenclature based on the evolutionary origin

    A concept for major incident triage: full-scaled simulation feasibility study

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    <p>Abstract</p> <p>Background</p> <p>Efficient management of major incidents involves triage, treatment and transport. In the absence of a standardised interdisciplinary major incident management approach, the Norwegian Air Ambulance Foundation developed Interdisciplinary Emergency Service Cooperation Course (TAS). The TAS-program was established in 1998 and by 2009, approximately 15 500 emergency service professionals have participated in one of more than 500 no-cost courses. The TAS-triage concept is based on the established triage Sieve and Paediatric Triage Tape models but modified with slap-wrap reflective triage tags and paediatric triage stretchers. We evaluated the feasibility and accuracy of the TAS-triage concept in full-scale simulated major incidents.</p> <p>Methods</p> <p>The learners participated in two standardised bus crash simulations: without and with competence of TAS-triage and access to TAS-triage equipment. The instructors calculated triage accuracy and measured time consumption while the learners participated in a self-reported before-after study. Each question was scored on a 7-point Likert scale with points labelled "Did not work" (1) through "Worked excellent" (7).</p> <p>Results</p> <p>Among the 93 (85%) participating emergency service professionals, 48% confirmed the existence of a major incident triage system in their service, whereas 27% had access to triage tags. The simulations without TAS-triage resulted in a mean over- and undertriage of 12%. When TAS-Triage was used, no mistriage was found. The average time from "scene secured to all patients triaged" was 22 minutes (range 15-32) without TAS-triage vs. 10 minutes (range 5-21) with TAS-triage. The participants replied to "How did interdisciplinary cooperation of triage work?" with mean 4,9 (95% CI 4,7-5,2) before the course vs. mean 5,8 (95% CI 5,6-6,0) after the course, p < 0,001.</p> <p>Conclusions</p> <p>Our modified triage Sieve tool is feasible, time-efficient and accurate in allocating priority during simulated bus accidents and may serve as a candidate for a future national standard for major incident triage.</p

    Live Coding, Live Notation, Live Performance

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    This paper/demonstration explores relationships between code, notation including representation, visualisation and performance. Performative aspects of live coding activities are increasingly being investigated as the live coding movement continues to grow and develop. Although live instrumental performance is sometimes included as an accompaniment to live coding, it is often not a fully integrated part of the performance, relying on improvisation and/or basic indicative forms of notation with varying levels of sophistication and universality. Technologies are developing which enable the use of fully explicit music notations as well as more graphic ones, allowing more fully integrated systems of code in and as performance which can also include notations of arbitrary complexity. This itself allows the full skills of instrumental musicians to be utilised and synchronised in the process. This presentation/demonstration presents work and performances already undertaken with these technologies, including technologies for body sensing and data acquisition in the translation of the movements of dancers and musicians into synchronously performable notation, integrated by live and prepared coding. The author together with clarinetist Ian Mitchell present a short live performance utilising these techniques, discuss methods for the dissemination and interpretation of live generated notations and investigate how they take advantage of instrumental musicians’ training-related neuroplasticity skills

    Avaliação do Ensino de Empreendedorismo entre Estudantes Universitários por meio do Perfil Empreendedor

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    Entrepreneurship is a socioeconomic phenomenon that has been valued for its influence on the growth and development of regional and national economies. The main promoter of this phenomenon are entrepreneurs, subjects endowed with multiple features that make up their profiles. They are dynamic and results oriented, benefitting from the fruits of their own personal efforts. Entrepreneurial education is highlighted as one of the most efficient ways to promote an entrepreneurial culture and train new entrepreneurs. However, some difficulty has been observed in assessing the effectiveness of teaching and learning this subject. The objective of this study was to analyze, by means of multivariate techniques, an instrument whose function is to measure the learning of Entrepreneurship, verifying the change in entrepreneur profiles of 407 college students participating or not in an entrepreneurial training process. The results showed that students who participated in Entrepreneurship educational training activities showed significant changes in their entrepreneurial profiles. The main contributions showed growth in the Self-realization, Planner, Innovative and Risks Assumed dimensions

    Computational Systems for Music Improvisation

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    Computational music systems that afford improvised creative interaction in real time are often designed for a specific improviser and performance style. As such the field is diverse, fragmented and lacks a coherent framework. Through analysis of examples in the field we identify key areas of concern in the design of new systems, which we use as categories in the construction of a taxonomy. From our broad overview of the field we select significant examples to analyse in greater depth. This analysis serves to derive principles that may aid designers scaffold their work on existing innovation. We explore successful evaluation techniques from other fields and describe how they may be applied to iterative design processes for improvisational systems. We hope that by developing a more coherent design and evaluation process, we can support the next generation of improvisational music systems
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