1,706 research outputs found

    Big Bang Nucleosynthesis with Gaussian Inhomogeneous Neutrino Degeneracy

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    We consider the effect of inhomogeneous neutrino degeneracy on Big Bang nucleosynthesis for the case where the distribution of neutrino chemical potentials is given by a Gaussian. The chemical potential fluctuations are taken to be isocurvature, so that only inhomogeneities in the electron chemical potential are relevant. Then the final element abundances are a function only of the baryon-photon ratio η\eta, the effective number of additional neutrinos ΔNν\Delta N_\nu, the mean electron neutrino degeneracy parameter ξˉ\bar \xi, and the rms fluctuation of the degeneracy parameter, σξ\sigma_\xi. We find that for fixed η\eta, ΔNν\Delta N_\nu, and ξˉ\bar \xi, the abundances of helium-4, deuterium, and lithium-7 are, in general, increasing functions of σξ\sigma_\xi. Hence, the effect of adding a Gaussian distribution for the electron neutrino degeneracy parameter is to decrease the allowed range for η\eta. We show that this result can be generalized to a wide variety of distributions for ξ\xi.Comment: 9 pages, 3 figures, added discussion of neutrino oscillations, altered presentation of figure

    LAPS Lidar Measurements at the ARM Alaska Northslope Site (Support to FIRE Project)

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    This report consists of data summaries of the results obtained during the May 1998 measurement period at Barrow Alaska. This report does not contain any data interpretation or analysis of the results which will follow this activity. This report is forwarded with a data set on magnetic media which contains the reduced data from the LAPS lidar in 15 minute intervals. The data was obtained during the period 15-30 May 1998. The measurement period overlapped with several aircraft flights conducted by NASA as part of the FIRE project. The report contains a summary list of the data obtained plus figures that have been prepared to help visualize the measurement periods. The order of the presentation is as follows: Section 1. A copy of the Statement of Work for the planned activity of the second measurement period at the ARM Northslope site is provided. Section 2. A list of the data collection periods shows the number of one minute data records stored during each hour of operation and the corresponding size (Mbytes) of the one hour data folders. The folder and file names are composed from the year, month, day, hour and minute. The date/time information is given in UTC for easier comparison with other data sets. Section 3. A set of 4 comparisons between the LAPS lidar results and the sondes released by the ARM scientists from a location nearby the lidar. The lidar results show the +/- 1 sigma statistical error on each of the independent 75 m altitude bins of the data. This set of 4 comparisons was used to set and validate the calibration value which was then used for the complete data set. Section 4. A set of false color figures with up to 10 hours of specific humidity measurements are shown in each graph. Two days of measurements are shown on each page. These plots are crude representations of the data and permit a survey which indicates when the clouds were very low or where interesting events may occur in the results. These plots are prepared using the real time sequence plot program which has no smoothing in either the altitude or time (except that you are allowed to pick the integration time and time step. All of these plots were prepared with 15 minute integration and 5 minute time step. Section 5. A set of time sequence data for all of the extended observation periods are shown with a smoothing algorithm from the Matlab plotting library. Most of these data are integrated for 5 minutes and stepped at I minute intervals but several plots are shown with both 15 minute integration and 5 minute steps. The upper level on these data was selected and converted to the white background where the error in the specific humidity reached 25%. Section 6. The set of one hour integrated plots shown with up to 4 hours per page are provided- from the real time analysis snapshot program. The only difference in these plots and the real time display is that the plots are stopped at an altitude where the error appears to be too large for the data to contain any meaningful information

    Isolated quadriceps training restores whole body exercise capacity in CHF

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    Patients with Chronic Heart Failure (CHF) are commonly characterized by exercise limitation. The benefit of isolated (i.e., small muscle mass) muscle training and its potential translation to whole body exercise in patients CHF has been recognized, however the mechanisms responsible for this positive outcome remain poorly understood. To study oxygen (O2) transport and metabolism at maximal cycle (whole body) and knee extensor (KE, small muscle mass) exercise in this pathological condition, eight healthy controls and six patients with CHF with reduced ejection fraction commenced 8 weeks of KE training (both legs, separately). Before and after training, they underwent cycle and KE maximal exercise studies. Pre-training cycling and KE exercise peak leg O2 uptake (VO2) were 17% and 15% lower, respectively, in the patients compared to controls. Although KE training did not alter cardiac output at maximal KE or cycle exercise, it increased O2 delivery (by 54%), arterial-venous O2 difference (by 10%), and muscle O2 conductance (by 39%) at maximal KE exercise, yielding an increase in peak single leg VO2 of 53%, which exceeded untrained control subject values. Post-training, during maximal cycling, O2 delivery (40%), arterial-venous O2 difference (15%), and muscle O2 conductance (DMO2) (52%) all increased, yielding a 40% greater peak leg VO2, matching that of the controls. Small muscle mass exercise training-induced improvements in both peripheral convective and diffusive O2 transport and subsequent O2 utilization were the main mechanisms responsible for the increased whole body exercise capacity in patients with CHF. Such clear improvements in these factors and exercise capacity support the efficacy of small muscle mass training as a powerful approach to promote a metabolic reserve and maintain physical function in the face of continuing central limitations associated with CHF

    Non equilibrium spectra of degenerate relic neutrinos

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    We calculate the exact kinetic evolution of cosmic neutrinos until complete decoupling, in the case when a large neutrino asymmetry exists. While not excluded by present observations, this large asymmetry can have relevant cosmological consequences and in particular may be helpful in reconciling Primordial Nucleosynthesis with a high baryon density as suggested by the most recent observations of the Cosmic Microwave Background Radiation. By solving numerically the Boltzmann kinetic equations for the neutrino distribution functions, we find the momentum-dependent corrections to the equilibrium spectra and briefly discuss their phenomenological implications.Comment: 30 pages, 17 figures, version to be publishe

    Síndrome metabólica e disfunção eréctil - avaliação de parâmetros clínicos e hemodinâmicos

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    Objetivos Calcular a prevalência de fatores de risco cardiovascular, incluindo a síndrome metabólica (SM), numa série de doentes portugueses com disfunção erétil (DE) e quantificar o impacto individual e agregado dos mesmos, nos parâmetros hemodinâmicos e no grau de severidade reportada. Material e métodos Estudo de uma série de 408 doentes com DE seguidos em consulta de Urologia, no período 2008-2010. A SM foi definida pelos critérios propostos pela National Cholesterol Education Program-Adult Treatment Panel III (NCEP-ATP III), tendo sido quantificadas as variáveis hipertensão arterial (HTA), intolerância a glicose (IG), hipertrigliceridemia (HTG), diminuição de HDL e obesidade central, sob a forma dicotómica. O estudo hemodinâmico foi efetuado por eco-doppler peniano dinâmico (D-PCDU) e a avaliação da severidade da DE recorrendo ao questionário International Index of Erectile Function 5-questions (IIEF-5). Resultados Verificou-se uma prevalência elevada de HTA (46,3%), IG (36,0%), HTG (24,8%), diminuição de HDL (22,3%) e obesidade central (41,2%). A prevalência de SM foi de 26,5%. O IIEF-5 e o pico de velocidade sistólica (PSV) apresentaram medianas de 12,0 e 34,0 cm/s, respetivamente. As análises multivariadas revelaram a HTA e a IG como fatores independentes influenciando negativamente o valor do PSV (p = 0,002) e o score do IEEF-5 (p = 0,010), respetivamente. Conclusão Enfatiza-se a elevada prevalência de fatores de risco cardiovascular numa população de doentes com DE, assim como a forte associação independente da HTA ao agravamento dos parâmetros hemodinâmicos da função erétil.Objectives To estimate the prevalence of cardiovascular risk factors, including metabolic syndrome (MS), in a series of Portuguese patients with erectile dysfunction (ED) and to quantify their individual and aggregate role regarding penile hemodynamics and degree of ED severity. Material and methods A cross-sectional study of 408 patients seen in the Urology Department of Hospital Sao João (Portugal) within the period 2008-2010 was performed. MS was defined in accordance with the National Cholesterol Education Program-Adult Treatment Panel III (NCEP-ATP III) criteria. For this purpose, we used the dichotomized variables: hypertension (HTA), glucose intolerance (GI), hypertriglyceridemia (HTG), decreased HDL cholesterol and central obesity. Penile hemodynamics were measured using the dynamic penile color Doppler ultrasound (D-PCDU) and ED severity was assessed with the International Index of Erectile Function-5 questions (IIEF-5). Results There was high prevalence of HTA (46.3%), GI (36.0%), HTG (24.8%), decreased HDL (22.3%) and central obesity (41.2%). Prevalence of MS was 26.5%. The median of IIEF-5 and peak systolic velocity (PSV) was 12.0 and 34.0 cms, respectively. Multivariate analysis revealed HTA and GI as independent factors decreasing the value of PSV (p = .002) and the score IEEF-5 (p = .010), respectively. Conclusion We emphasize the high prevalence of cardiovascular risk factors in a population of patients with ED as well as the strong independent association between AHT and hemodynamic worsening of erectile function

    Identification of Saturn's magnetospheric regions and associated plasma processes: Synopsis of Cassini observations during orbit insertion

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94634/1/rog1672.pd

    Auroral signatures of multiple magnetopause reconnection at Saturn

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    Auroral observations capture the ionospheric response to dynamics of the whole magnetosphere and may provide evidence of the significance of reconnection at Saturn. Bifurcations of the main dayside auroral emission have been related to reconnection at the magnetopause and their surface is suggested to represent the amount of newly opened flux. This work is the first presentation of multiple brightenings of these auroral features based on Cassini ultraviolet auroral observations. In analogy to the terrestrial case, we propose a process, in which a magnetic flux tube reconnects with other flux tubes at multiple sites. This scenario predicts the observed multiple brightenings, it is consistent with subcorotating auroral features which separate from the main emission, and it suggests north-south auroral asymmetries. We demonstrate that the conditions for multiple magnetopause reconnection can be satisfied at Saturn, like at Earth

    Written information about individual medicines for consumers.

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    Medicines are the most common intervention in most health services. As with all treatments, those taking medicines need sufficient information: to enable them to take and use the medicines effectively, to understand the potential harms and benefits, and to allow them to make an informed decision about taking them. Written medicines information, such as a leaflet or provided via the Internet, is an intervention that may meet these purposes

    Manual therapies for migraine: a systematic review

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    Migraine occurs in about 15% of the general population. Migraine is usually managed by medication, but some patients do not tolerate migraine medication due to side effects or prefer to avoid medication for other reasons. Non-pharmacological management is an alternative treatment option. We systematically reviewed randomized clinical trials (RCTs) on manual therapies for migraine. The RCTs suggest that massage therapy, physiotherapy, relaxation and chiropractic spinal manipulative therapy might be equally effective as propranolol and topiramate in the prophylactic management of migraine. However, the evaluated RCTs had many methodological shortcomings. Therefore, any firm conclusion will require future, well-conducted RCTs on manual therapies for migraine
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