267 research outputs found

    Childhood Asthma Utilization Rates in a Nonsmoking Population of Utah Compared to State and National Rates

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    Risk factors, such as parental smoking, are commonly associated with increased asthma symptoms and hospitalizations of children. Deseret Mutual Benefits Administrators (DMBA) is the health insurer for employees of The Church of Jesus Christ of Latter-day Saints and their families. Due to religious proscription, employees abstain from alcohol and tobacco use, creating a cohort of children not exposed to parental smoking. Calculation of hospitalization rates for DMBA, Utah, and the US were made in children to compare rates between a nonsmoking population and general populations. Compared to DMBA, rate ratios for asthma hospitalization and emergency department asthma visits were higher for the US and Utah. The incidence of hospital outpatient department and physician office visits was significantly greater for the US population compared to the DMBA. This study demonstrates a decreased need for health services used by children not exposed to second-hand smoke

    First-principles modeling of complexions at the phase boundaries in Ti-doped WC-Co cemented carbides at finite temperatures

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    WC-Co cemented carbides have a unique combination of high hardness and good toughness, making them ideal as tool materials in applications such as metal machining or rock drilling. Dopants are commonly added to retard grain growth and thereby creating a harder material. Thin films with cubic structure have been observed experimentally at phase boundaries between hexagonal WC and fcc Co-rich binder when doping with, e.g., Ti, V, or Cr. These films are generally considered to play a crucial role in the grain growth inhibition effect. Therefore, the thermodynamics of these thin cubic films is important to understand. Here, we construct, using ab initio calculations and modeling, an interfacial phase diagram for thin cubic films in Ti-doped WC-Co. We consider C↔vacancy and W↔Ti substitutions by constructing alloy cluster expansions and use Monte Carlo simulations to calculate the configurational free energy. Furthermore, force-constant fitting is used to extract the harmonic free energy for the ground-state structures. Additionally, we use information from thermodynamic databases to couple our atomic-scale calculations to overall compositions of typical WC-Co materials. We predict that Ti segregates to WC/Co phase boundaries to form thin cubic films of two metallic layer thickness, both at solid-state and liquid-phase sintering temperatures. Furthermore, we predict that these films are stable also for low doping concentrations when no Ti-containing carbide phase precipitates in the material. We show that Ti essentially only segregates to the inner layer of the thin cubic film leaving an almost pure W layer towards Co, an ordering which has been observed in recent experimental high-resolution transmission electron microscopy studies

    Crotalus atrox venom preconditioning increases plasma fibrinogen and reduces perioperative hemorrhage in a rat model of surgical brain injury.

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    Perioperative bleeding is a potentially devastating complication in neurosurgical patients, and plasma fibrinogen concentration has been identified as a potential modifiable risk factor for perioperative bleeding. The aim of this study was to evaluate preconditioning with Crotalus atrox venom (Cv-PC) as potential preventive therapy for reducing perioperative hemorrhage in the rodent model of surgical brain injury (SBI). C. atrox venom contains snake venom metalloproteinases that cleave fibrinogen into fibrin split products without inducing clotting. Separately, fibrinogen split products induce fibrinogen production, thereby elevating plasma fibrinogen levels. Thus, the hypothesis was that preconditioning with C. atrox venom will produce fibrinogen spilt products, thereby upregulating fibrinogen levels, ultimately improving perioperative hemostasis during SBI. We observed that Cv-PC SBI animals had significantly reduced intraoperative hemorrhage and postoperative hematoma volumes compared to those of vehicle preconditioned SBI animals. Cv-PC animals were also found to have higher levels of plasma fibrinogen at the time of surgery, with unchanged prothrombin time. Cv-PC studies with fractions of C. atrox venom suggest that snake venom metalloproteinases are largely responsible for the improved hemostasis by Cv-PC. Our findings indicate that Cv-PC increases plasma fibrinogen levels and may provide a promising therapy for reducing perioperative hemorrhage in elective surgeries

    Grain size and organic carbon controls polyaromatic hydrocarbons (PAH), mercury (Hg) and toxicity of surface sediments in the River Conwy Estuary, Wales, UK

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    The Conwy estuary was evaluated for sediment quality. Microtox bioassay revealed 38 of 39 sites were non-toxic. Hg ranged from 0.001 to 0.153 μg kg−1, mean 0.026 mg kg−1, Σ16 PAH from 18 to 1578 μg kg−1, mean 269 μg kg−1, Σ22 PAH, 18 to 1871 μg kg−1 mean to 312 μg kg−1, two sites had high perylene relative to ΣPAH. Σ22PAH correlated positively with TOC, clay and silt (R2 0.89, 0.92, 0.90) and negatively with sand. Multivariate statistics, delineated four spatial (site) and five variable (measurements) clusters. Spatial clustering relates to sediment grain size, in response to hydrodynamic processes in estuary; fine (clay to silt) sized sediments exhibit the highest Hg and PAH content, because these components partitioned into the fine fraction. Comparison to national and international environmental standards suggests Hg and PAH content of Conwy sediments are unlikely to harm ecology or transfer up into the human food chain

    Neurochemical Aftermath of Repetitive Mild Traumatic Brain Injury

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    IMPORTANCE: Evidence is accumulating that repeated mild traumatic brain injury (mTBI) incidents can lead to persistent, long-term debilitating symptoms and in some cases a progressive neurodegenerative condition referred to as chronic traumatic encephalopathy. However, to our knowledge, there are no objective tools to examine to which degree persistent symptoms after mTBI are caused by neuronal injury. OBJECTIVE: To determine whether persistent symptoms after mTBI are associated with brain injury as evaluated by cerebrospinal fluid biochemical markers for axonal damage and other aspects of central nervous system injury. DESIGN, SETTINGS, AND PARTICIPANTS: A multicenter cross-sectional study involving professional Swedish ice hockey players who have had repeated mTBI, had postconcussion symptoms for more than 3 months, and fulfilled the criteria for postconcussion syndrome (PCS) according to the Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) matched with neurologically healthy control individuals. The participants were enrolled between January 2014 and February 2016. The players were also assessed with Rivermead Post Concussion Symptoms Questionnaire and magnetic resonance imaging. MAIN OUTCOMES AND MEASURES: Neurofilament light protein, total tau, glial fibrillary acidic protein, amyloid β, phosphorylated tau, and neurogranin concentrations in cerebrospinal fluid. RESULTS: A total of 31 participants (16 men with PCS; median age, 31 years; range, 22-53 years; and 15 control individuals [11 men and 4 women]; median age, 25 years; range, 21-35 years) were assessed. Of 16 players with PCS, 9 had PCS symptoms for more than 1 year, while the remaining 7 returned to play within a year. Neurofilament light proteins were significantly increased in players with PCS for more than 1 year (median, 410 pg/mL; range, 230-1440 pg/mL) compared with players whose PCS resolved within 1 year (median, 210 pg/mL; range, 140-460 pg/mL) as well as control individuals (median 238 pg/mL, range 128-526 pg/mL; P = .04 and P = .02, respectively). Furthermore, neurofilament light protein concentrations correlated with Rivermead Post Concussion Symptoms Questionnaire scores and lifetime concussion events (ρ = 0.58, P = .02 and ρ = 0.52, P = .04, respectively). Overall, players with PCS had significantly lower cerebrospinal fluid amyloid-β levels compared with control individuals (median, 1094 pg/mL; range, 845-1305 pg/mL; P = .05). CONCLUSIONS AND RELEVANCE: Increased cerebrospinal fluid neurofilament light proteins and reduced amyloid β were observed in patients with PCS, suggestive of axonal white matter injury and amyloid deposition. Measurement of these biomarkers may be an objective tool to assess the degree of central nervous system injury in individuals with PCS and to distinguish individuals who are at risk of developing chronic traumatic encephalopathy

    Blood biomarkers indicate mild neuroaxonal injury and increased amyloid production after transient hypoxia during breath-hold diving

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    OBJECTIVE: To determine whether transient hypoxia during breath-hold diving causes neuronal damage or dysfunction or alters amyloid metabolism as measured by certain blood biomarkers. DESIGN: Sixteen divers competing in the national Swedish championship in breath-hold diving and five age-matched healthy control subjects were included. Blood samples were collected at baseline and over a course of 3 days where the divers competed in static apnea (STA), dynamic apnea without fins (DYN1) and dynamic apnea with fins (DYN2). MAIN OUTCOMES: Biomarkers reflecting brain injury and amyloid metabolism were analysed in serum (S-100β, NFL) and plasma (T-tau, Aβ42) using immunochemical methods. RESULTS: Compared to divers’ baseline, Aβ42 increased after the first event of static apnea (p = 0.0006). T-tau increased (p = 0.001) in STA vs baseline and decreased after one of the dynamic events, DYN2 (p = 0.03). Further, T-tau correlated with the length of the apneic time during STA (ρ = 0.7226, p = 0.004) and during DYN1 (ρ = 0.66, p = 0.01). CONCLUSION: The findings suggest that transient hypoxia may acutely increase the levels of Aβ42 and T-tau in plasma of healthy adults, further supporting that general hypoxia may cause mild neuronal dysfunction or damage and stimulate Aβ production

    Beyond Modes: Building a Secure Record Protocol from a Cryptographic Sponge Permutation

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    Abstract. BLINKER is a light-weight cryptographic suite and record protocol built from a single permutation. Its design is based on the Sponge construction used by the SHA-3 algorithm KECCAK. We examine the SpongeWrap authen-ticated encryption mode and expand its padding mechanism to offer explicit do-main separation and enhanced security for our specific requirements: shared se-cret half-duplex keying, encryption, and a MAC-and-continue mode. We motivate these enhancements by showing that unlike legacy protocols, the resulting record protocol is secure against a two-channel synchronization attack while also having a significantly smaller implementation footprint. The design facilitates security proofs directly from a single cryptographic primitive (a single security assump-tion) rather than via idealization of multitude of algorithms, paddings and modes of operation. The protocol is also uniquely suitable for an autonomous or semi-autonomous hardware implementation of protocols where the secrets never leave the module, making it attractive for smart card and HSM designs

    Rhythmanalysing marathon running: ‘A drama of rhythms’

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    © 2017, © The Author(s) 2017. This paper draws on Lefebvre’s rhythmanalysis to investigate the multiple rhythms of the Berlin Marathon, exemplifying and expanding understandings about the rhythms of places and mobilities. First, we discuss how isorhythmic order is imposed on the city and event by race organizers. Secondly, we show that a marathon depends upon the preparatory training or ‘dressage’ performed by the thousands who have made themselves ‘race-ready’. Thirdly, we explore the changing individual and collective rhythms that continuously emerge according to contingencies and stages of the race to compose an unfolding drama of rhythms that includes both arrhythmic and eurhythmic experiences

    Assessment of Forest Biomass and Carbon Stocks at Stand Level Using Site-Specific Primary Data to Support Forest Management

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    To quantify and map woody biomass (WB) and forest carbon (C) stocks, several models were developed. They differ in terms of scale of application, details related to the input data required and outputs provided. Local Authorities, such as Mountain Communities, can be supported in sustainable forest planning and management by providing specific models in which the reference unit is the same as the one reported in the Forest Management Plans (FMP), i.e. the forest stand. In the Lombardy Region (Northern Italy), a few studies were performed to assess WB and forest C stocks, and they were generally based on data coming from regional\u2014or national\u2014forest inventories and remote sensing, without taking into account data collected in the FMPs. For this study, the first version of the stand-level model \u201cWOody biomass and Carbon ASsessment\u201d (WOCAS) for WB and C stocks calculation was improved into a second version (WOCAS v2) and preliminary results about its first application to 2019 forest stands of Valle Camonica District (Lombardy Region) are presented. Since the model WOCAS uses the growing stock as the main driver for the calculation, it can be applied in any other forest area where the same input data are available
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