665 research outputs found
POES satellite observations of EMIC-wave driven relativistic electron precipitation during 1998-2010
[1] Using six Polar Orbiting Environmental Satellites (POES) satellites that have carried the Space Environment Module-2 instrument package, a total of 436,422 individual half-orbits between 1998 and 2010 were inspected by an automatic detection algorithm searching for electromagnetic ion cyclotron (EMIC) driven relativistic electron precipitation (REP). The algorithm searched for one of the key characteristics of EMIC-driven REP, identified as the simultaneity between spikes in the P1 (52 keV differential proton flux channel) and P6 (>800 keV electron channel). In all, 2331 proton precipitation associated REP (PPAREP) events were identified. The majority of events were observed at L-values within the outer radiation belt (3 < L < 7) and were more common in the dusk and night sectors as determined by magnetic local time. The majority of events occurred outside the plasmasphere, at L-values ~1 Re greater than the plasmapause location determined from two different statistical models. The events make up a subset of EMIC-driven proton spikes investigated by Sandanger et al. (2009), and potentially reflect different overall characteristics compared with proton spikes, particularly when comparing their location to that of the plasmapause, i.e., EMIC-driven proton precipitation inside the plasmapause, and potentially EMIC-driven REP outside the plasmapause. There was no clear relationship between the location of plasmaspheric plumes and the locations of the PPAREP events detected. Analysis of the PPAREP event occurrence indicates that high solar wind speed and high geomagnetic activity levels increase the likelihood of an event being detected. The peak PPAREP event occurrence was during the declining phase of solar cycle 23, consistent with the 2003 maximum in the geomagnetic activity index, Ap
Apolipoprotein ɛ4 and neuropsychological performance in Alzheimer's disease and vascular dementia
Preliminary Findings of an Elk Brucellosis Surveillance and Epidemiology Project in Southwestern Montana
Brucellosis is a bacterial disease that causes abortions in cattle, bison (Bison bison) and elk (Cervus elaphus). Transmission of the disease from wildlife to cattle has serious financial implications to producers and the livestock industry in Montana. Brucellosis in elk populations of southwestern Montana results in reduced tolerance for elk on private property and can influence management of elk populations. In the winter of 2010/2011, Montana Fish, Wildlife and Parks initiated a five-year project with the goals of delineating the geographical distribution of brucellosis in elk populations, enhancing our understanding of how brucellosis functions in elk populations, and evaluating factors that may influence the spread and prevalence of brucellosis in elk. One-hundred adult female elk were captured in hunting districts (HD) 324 and 326 in the winter of 2010/2011 with eight testing positive on blood tests(seropositive) in the field for exposure to Brucella. Ninety-three adult female elk were captured in HD 325 in the winter of 2011/2012, five of which were seropositive. Elk testing positive in the field were fitted with a GPS collar and, if pregnant, implanted with a vaginal implant transmitter (VIT). Seropositive pregnant elk were tracked from the ground and air 2-3 times/week in order to locate birth or abortion sites. B. abortus was not cultured from VITs or samples collected at birth sites in the first year of the project. B. abortus was cultured from tissues or VITs associated with two aborted calves in 2012. The known distribution of brucellosis in elk has expanded based on information obtained in this study
Prevalence of reducing carbohydrate intake and fasted training in elite endurance athletes and association with bone injury
There are conflicting reports both within the lay media and scientific literature regarding the use and benefit of dietary practices that aim to reduce CHO intake in endurance athletes. This study aimed to determine the prevalence of intentional reduction of CHO intake and fasted training in elite endurance-based athletes using a semi-quantitative questionnaire. Bone is a nutritionally modulated tissue; therefore, this study also aimed to explore if these dietary practices are potentially associated with bone injury incidence. The reported reduction of CHO intake was prevalent (28%) with the primary motivation being maintenance or manipulation of body composition. However, discrepancies in athletes' awareness of CHO intake were identified providing a potential avenue of intervention especially within applied practice. The use of fasted training was more prevalent (38%) with athletes using this practice for both body composition manipulation and promoting a desired adaptive response. Forty-four per cent of participants had suffered a radiographically confirmed bone injury at some point in their career. There was no association between reduction in CHO intake and bone injury incidence; however, the incidence of bone injury was 1.61 times higher in those who currently use fasted training compared to those who have never used it or who have used it in the past. Although a direct causal link between these dietary practices and the incidence of bone injury cannot be drawn, it provides robust justification for future investigations of the potential mechanisms that could explain this finding
Oral Bromelain Attenuates Inflammation in an Ovalbumin-induced Murine Model of Asthma
Bromelain, a widely used pineapple extract with cysteine protease activity, has been shown to have immunomodulatory effects in a variety of immune system models. The purpose of the present study was to determine the effects of orally administered bromelain in an ovalbumin (OVA)-induced murine model of acute allergic airway disease (AAD). To establish AAD, female C57BL/6J mice were sensitized with intraperitoneal (i.p.) OVA/alum and then challenged with OVA aerosols for 3 days. Mice were gavaged with either (phosphate buffered saline)PBS or 200 mg/kg bromelain in PBS, twice daily for four consecutive days, beginning 1 day prior to OVA aerosol challenge. Airway reactivity and methacholine sensitivity, bronchoalveolar lavage (BAL) cellular differential, Th2 cytokines IL-5 and IL-13, and lung histology were compared between treatment groups. Oral bromelain-treatment of AAD mice demonstrated therapeutic efficacy as evidenced by decreased methacholine sensitivity (P ≤ 0.01), reduction in BAL eosinophils (P ≤ 0.02) and IL-13 concentrations (P ≤ 0.04) as compared with PBS controls. In addition, oral bromelain significantly reduced BAL CD19+ B cells (P ≤ 0.0001) and CD8+ T cells (P ≤ 0.0001) in AAD mice when compared with controls. These results suggest that oral treatment with bromelain had a beneficial therapeutic effect in this murine model of asthma and bromelain may also be effective in human conditions
Optimisation of singlet oxygen production from photosensitiser-incorporated, medically-relevant hydrogels
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