2,079 research outputs found

    Monadic Functional Reactive Programming

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    Functional Reactive Programming (FRP) is a way to program reactive systems in functional style, eliminating many of the problems that arise from imperative techniques. In this paper, we present an alternative FRP formulation that is based on the notion of a reactive computation: a monadic computation which may require the occurrence of external events to continue. A signal computation is a reactive computation that may also emit values. In contrast to signals in other FRP formulations, signal computations can end, leading to a monadic interface for sequencing signal phases. This interface has several advantages: routing is implicit, sequencing signal phases is easier and more intuitive than when using the switching combinators found in other FRP approaches, and dynamic lists require much less boilerplate code. In other FRP approaches, either the entire FRP expression is re-evaluated on each external stimulus, or impure techniques are used to prevent redundant re-computations. We show how Monadic FRP can be implemented straightforwardly in a purely functional way while preventing redundant re-computations

    Evidence for cross-protection but not type-replacement over the 11 years after human papillomavirus vaccine introduction

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    Examination of cross-protection and type replacement after human papillomavirus (HPV) vaccine introduction is essential to guide vaccination recommendations and policies. The aims of this study were to examine trends in non-vaccine-type HPV: 1) genetically related to vaccine types (to assess for cross-protection) and 2) genetically unrelated to vaccine types (to assess for type replacement), among young women 13-26 years of age during the 11 years after HPV vaccine introduction. Participants were recruited from a hospital-based teen health center and a community health department for four cross-sectional surveillance studies between 2006 and 2017. Participants completed a survey that assessed sociodemographic characteristics and behaviors, and cervicovaginal swabs were collected and tested for 36 HPV genotypes. We determined changes in proportions of non-vaccine-type HPV prevalence and conducted logistic regression to determine the odds of infection across the surveillance studies, propensity-score adjusted to control for selection bias. Analyses were stratified by vaccination status. Among vaccinated women who received only the 4-valent vaccine (n = 1,540), the adjusted prevalence of HPV types genetically related to HPV16 decreased significantly by 45.8% (adjusted odds ratio [AOR] = 0.48, 95% confidence interval [CI] = 0.31-0.74) from 2006-2017, demonstrating evidence of cross-protection. The adjusted prevalence of HPV types genetically related to HPV18 did not change significantly (14.2% decrease, AOR = 0.83, 95% CI = 0.56-1.21). The adjusted prevalence of HPV types genetically unrelated to vaccine types did not change significantly (4.2% increase, AOR = 1.09, CI = 0.80-1.48), demonstrating no evidence of type replacement. Further studies are needed to monitor for cross-protection and possible type replacement after introduction of the 9-valent HPV vaccine

    Bio-inspired Sensing and Actuating Architectures for Feedback Control of Civil Structures

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    Civil structures, such as buildings and bridges, are constantly at risk of failure due to external environmental loads, such as earthquakes or strong winds. To minimize the effects of these loads, active feedback control systems have been proposed but such systems still face numerous challenges which impede their widespread adoption. In order to overcome many of these challenges, inspiration can be drawn from the signal processing and actuating techniques employed by the biological central nervous system to develop a bio-inspired control algorithm. In this study the front-end, signal processing techniques employed by biological sensory systems, and in particular the mammalian auditory system, are drawn upon in order to alleviate computations at the actuation node. This results in a simplistic control law that is a weighted combination of input information about the structure\u27s response such that F   =   WN , where F is the applied control force, W is a pre-determined weighting matrix, and N is a deconstructed representation of the structural response to the applied excitation. There is no empirical solution for deriving an optimal weighting matrix, W , and in this study numerous methods are explored in order to determine values for this matrix that produce the most effective control. These methods include particle swarm optimization, artificial neural networks, and optimal control theory. The various weighting matrices are integrated into the proposed bio-inspired control algorithm and applied in simulation to a five story benchmark structure. These methods are also compared to a traditional linear quadratic regulator (LQR) to gain insight into the overall performance of the bio-inspired control algorithm. Of the three training techniques, the particle swarm optimization technique offers the most effective control which is comparable in performance to the traditional LQR

    Links between traumatic brain injury and ballistic pressure waves originating in the thoracic cavity and extremities

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    Identifying patients at risk of traumatic brain injury (TBI) is important because research suggests prophylactic treatments to reduce risk of long-term sequelae. Blast pressure waves can cause TBI without penetrating wounds or blunt force trauma. Similarly, bullet impacts distant from the brain can produce pressure waves sufficient to cause mild to moderate TBI. The fluid percussion model of TBI shows that pressure impulses of 15-30 psi cause mild to moderate TBI in laboratory animals. In pigs and dogs, bullet impacts to the thigh produce pressure waves in the brain of 18-45 psi and measurable injury to neurons and neuroglia. Analyses of research in goats and epidemiological data from shooting events involving humans show high correlations (r > 0.9) between rapid incapacitation and pressure wave magnitude in the thoracic cavity. A case study has documented epilepsy resulting from a pressure wave without the bullet directly hitting the brain. Taken together, these results support the hypothesis that bullet impacts distant from the brain produce pressure waves that travel to the brain and can retain sufficient magnitude to induce brain injury. The link to long-term sequelae could be investigated via epidemiological studies of patients who were gunshot in the chest to determine whether they experience elevated rates of epilepsy and other neurological sequelae

    A Descriptive Analysis of the Appropriate Use of Cognitive Bias Terminology in Forensic Science Literature

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    Cognitive bias occurs without a person’s awareness and can affect decision-making abilities. In forensic science, bias can be especially detrimental to making accurate decisions about the evidence in a criminal investigation. There are many academic studies in identifying, describing, and suggesting ways to mitigate cognitive biases in forensic science. Many authors will give a known cognitive science concept a new name or create their own bias. This is a problem in the literature because nobody knows for sure how many published studies are referring to or testing the same phenomena since authors are using different definitions or terminology to describe the same concept. This study systematically identified bias terms that different domains of research use when conducting forensic science research. After identifying the bias term(s) used in each study, each error was categorized by domain (e.g., psychologists, lawyers, forensic scientists), by type of bias (e.g., confirmation bias, anchoring bias, made up bias term) and how the authors define the bias term (i.e., correct definition, incorrect definition, no definition, or made a new definition). Overall, this study shows that authors were more likely to use a correct bias term and bias definition (29%) than make up a bias term and bias definition (25%.) A majority of the authors in this study are not cognitive scientists and, therefore, are not heavily trained in cognitive terminology. The issue of the incorrect use of cognitive bias terminology is a serious one for forensic science and has yet to be noted or investigated until this preliminary analysis. The responsibility for forensic scientists who are not trained in cognitive science to understand the bias literature and to adopt the correct terminology is fundamental for proper communication among scientific professionals

    Scaling the heights of positive psychology: A systematic review of measurement scales

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    The volume of empirical research on positive psychology topics has grown substantially over the past two decades.  This review examines how constructs in positive psychology have been operationalized, measured, validated, cited, and applied to build the science. Based on an archive of 972 empirical articles linked to positive psychology, this review found that 762 articles used at least one measurement scale; 312 measures were created or adapted.  Findings reveal a wide range of scales being used to measure a variety of constructs, including scales on both life-enhancing and life-depleting constructs.  Key characteristics such as journals, constructs, and scale development and validation information are discussed.  There are some reliability analyses and validations occurring within the field, but the creation of new measures far outpaces the validation of existing measures.  Weaknesses such as multiple operationalizations may be rooted in inadequate discourse and synthesis.  We call for further cross-pollination for a more scientifically robust scholarship in positive psychology

    The Cdc31p-binding protein Kar1p is a component of the half bridge of the yeast spindle pole body

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    KAR1 has been identified as an essential gene which is involved in karyogamy of mating yeast cells and in spindle pole body duplication of mitotic cells (Rose, M. D., and G. R. Fink. 1987. Cell. 48:1047-1060). We investigated the cell cycle-dependent localization of the Kar1 protein (Kar1p) and its interaction with other SPB components. Kar1p is associated with the spindle pole body during the entire cell cycle of yeast. Immunoelectron microscopic studies with anti-Kar1p antibodies or with the monoclonal antibody 12CA5 using an epitope-tagged, functional Kar1p revealed that Kar1p is associated with the half bridge or the bridge of the spindle pole body. Cdc31p, a Ca(2+)-binding protein, was previously identified as the first component of the half bridge of the spindle pole body (Spang, A., I. Courtney, U. Fackler, M. Matzner, and E. Schiebel. 1993. J. Cell Biol. 123:405-416). Using an in vitro assay we demonstrate that Cdc31p specifically interacts with a short sequence within the carboxyl terminal half of Kar1p. The potential Cdc31p-binding sequence of Kar1p contains three acidic amino acids which are not found in calmodulin-binding peptides, explaining the different substrate specificities of Cdc31p and calmodulin. Cdc31p was also able to bind to the carboxy terminus of Nuflp/Spc110p, another component of the SPB (Kilmartin, J. V., S. L. Dyos, D. Kershaw, and J. T. Finch. 1993. J. Cell Biol. 123:1175-1184). The association of Kar1p with the spindle pole body was independent of Cdc31p. Cdc31p, on the other hand, was not associated with SPBs of kar1 cells

    First-principles prediction of redox potentials in transition-metal compounds with LDA+U

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    First-principles calculations within the Local Density Approximation (LDA) or Generalized Gradient Approximation (GGA), though very successful, are known to underestimate redox potentials, such as those at which lithium intercalates in transition metal compounds. We argue that this inaccuracy is related to the lack of cancellation of electron self-interaction errors in LDA/GGA and can be improved by using the DFT+UU method with a self-consistent evaluation of the UU parameter. We show that, using this approach, the experimental lithium intercalation voltages of a number of transition metal compounds, including the olivine Lix_{x}MPO4_{4} (M=Mn, Fe Co, Ni), layered Lix_{x}MO2_{2} (x=x=Co, Ni) and spinel-like Lix_{x}M2_{2}O4_{4} (M=Mn, Co), can be reproduced accurately.Comment: 19 pages, 6 figures, Phys. Rev. B 70, 235121 (2004

    Growth and texture of Spark Plasma Sintered Al2O3 ceramics: a combined analysis of X-rays and Electron Back Scatter Diffraction

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    Textured alumina ceramics were obtained by Spark Plasma Sintering (SPS) of undoped commercial a-Al2O3 powders. Various parameters (density, grain growth, grain size distribution) of the alumina ceramics, sintered at two typical temperatures 1400{\deg}C and 1700{\deg}C, are investigated. Quantitative textural and structural analysis, carried out using a combination of Electron Back Scattering Diffraction (EBSD) and X-ray diffraction (XRD), are represented in the form of mapping, and pole figures. The mechanical properties of these textured alumina ceramics include high elastic modulus and hardness value with high anisotropic nature, opening the door for a large range of applicationsComment: 16 pages, 6 figures, submitted to J. Appl. Phy
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