392 research outputs found

    Measuring antibiotic availability and use in 20 low- and middle-income countries

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    Objective To assess antibiotic availability and use in health facilities in low- and middle-income countries, using the service provision assessment and service availability and readiness assessment surveys. Methods We obtained data on antibiotic availability at 13 561 health facilities in 13 service provision assessment and 8 service availability and readiness assessment surveys. In 10 service provision assessment surveys, child consultations with health-care providers were observed, giving data on antibiotic use in 22 699 children. Antibiotics were classified as access, watch or reserve, according to the World Health Organization’s AWaRe categories. The percentage of health-care facilities across countries with specific antibiotics available and the proportion of children receiving antibiotics for key clinical syndromes were estimated. Findings The surveys assessed the availability of 27 antibiotics (19 access, 7 watch, 1 unclassified). Co-trimoxazole and metronidazole were most widely available, being in stock at 89.5% (interquartile range, IQR: 11.6%) and 87.1% (IQR: 15.9%) of health facilities, respectively. In contrast, 17 other access and watch antibiotics were stocked, by fewer than a median of 50% of facilities. Of the 22 699 children observed, 60.1% (13 638) were prescribed antibiotics (mostly co-trimoxazole or amoxicillin). Children with respiratory conditions were most often prescribed antibiotics (76.1%; 8972/11 796) followed by undifferentiated fever (50.1%; 760/1518), diarrhoea (45.7%; 1293/2832) and malaria (30.3%; 352/1160). Conclusion Routine health facility surveys provided a valuable data source on the availability and use of antibiotics in low- and middle-income countries. Many access antibiotics were unavailable in a majority of most health-care facilities

    The published research paper: is it an important indicator of successful operational research at programme level?

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    Is a published research paper an important indicator of successful operational research at programme level in low-income countries? In academia, publishing in peer-reviewed scientific journals is highly encouraged and strongly pursued for academic recognition and career progression. In contrast, for those who engage in operational research at programme level, there is often no necessity or reward for publishing the results of research studies; it may even be criticized as being an unnecessary detraction from programme-related work. We present arguments to support publishing operational research from low-income countries; we highlight some of the main reasons for failure of publication at programme level and suggest ways forward

    On the relation of standard and helical magnetorotational instability

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    The magnetorotational instability (MRI) plays a crucial role for cosmic structure formation by enabling turbulence in Keplerian disks which would be otherwise hydrodynamically stable. With particular focus on MRI experiments with liquid metals, which have small magnetic Prandtl numbers, it has been shown that the helical version of this instability (HMRI) has a scaling behaviour that is quite different from that of the standard MRI (SMRI). We discuss the relation of HMRI to SMRI by exploring various parameter dependencies. We identify the mechanism of transfer of instability between modes through a spectral exceptional point that explains both the transition from a stationary instability (SMRI) to an unstable travelling wave (HMRI) and the excitation of HMRI in the inductionless limit. For certain parameter regions we find new islands of the HMRI.Comment: 48 pages, 13 figure

    Nonaxisymmetric Magnetorotational Instability in Proto-Neutron Stars

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    We investigate the stability of differentially rotating proto-neutron stars (PNSs) with a toroidal magnetic field. Stability criteria for nonaxisymmetric MHD instabilities are derived using a local linear analysis. PNSs are expected to have much stronger radial shear in the rotation velocity compared to normal stars. We find that nonaxisymmetric magnetorotational instability (NMRI) with a large azimuthal wavenumber mm is dominant over the kink mode (m=1m=1) in differentially rotating PNSs. The growth rate of the NMRI is of the order of the angular velocity Ω\Omega which is faster than that of the kink-type instability by several orders of magnitude. The stability criteria are analogous to those of the axisymmetric magnetorotational instability with a poloidal field, although the effects of leptonic gradients are considered in our analysis. The NMRI can grow even in convectively stable layers if the wavevectors of unstable modes are parallel to the restoring force by the Brunt-V\"ais\"al\"a oscillation. The nonlinear evolution of NMRI could amplify the magnetic fields and drive MHD turbulence in PNSs, which may lead to enhancement of the neutrino luminosity.Comment: 24pages, 7figures, Accepted for publication in the Astrophysical Journal (December 12, 2005

    The Effects of Physical Activity on Markers of Hepatic Inflammation During Weight-Loss

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    Non-alcoholic fatty liver disease (NAFLD) represents a continuum that begins with accumulation of lipid in hepatic cells progressing to hepatic steatosis with inflammation (steatohepatitis), fibrosis, and cirrhosis. Weight-loss using dietary modification and physical activity are common strategies used for the treatment of NAFLD; however, it remains to be determined the effects of physical activity on hepatic inflammation during weight-loss. The purpose of this study was to determine the therapeutic role of physical activity on plasma and hepatic inflammatory markers during weight-loss. Male C57BL/6 mice were fed either a low-fat (LFD; 10% kcal fat) or high-fat (HFD; 60% kcal fat) diet for 10-weeks. Following 10-weeks, the HFD group was randomly assigned to either a LFD (Diet) or LFD with physical activity (Diet+PA) to induce weight loss for 8-weeks. After 8-weeks, reductions in body mass were observed in both Diet and Diet+PA groups (see Table 1.). Interestingly, the Diet+PA group lost significantly (P\u3c0.05) more body mass than the Diet group. Despite significant (P\u3c0.05) reductions in body mass and HOMA-IR, plasma TNF-α remained elevated in the Diet and Diet+PA groups. Moreover, Diet+PA plasma TNF-α was significantly (P\u3c0.05) greater than the HFD obese controls. Elevated plasma TNF-α in the Diet+PA was matched by a greater hepatic expression of IL-1β and IL-6 mRNA when compared to all groups. Interestingly, the expression of TGF-β1 mRNA was significantly (P\u3c0.05) reduced in the Diet+PA when compared to all groups. The elevated plasma TNF-α and expression of IL-1β and IL-6 mRNA are likely due to physical activity. It remains unclear as to the pro-inflammatory effects of physical activity during weight-loss; however, this may be part of a protective adaption to regular exercise. Furthermore, the reduced hepatic TGF-β1 mRNA levels suggest a protective strategy against fibrogenesis in the spectrum of liver disease. Table 1. Whole body and hepatic metabolic characteristics following weight-loss. Variables LFD (n=12) HFD (n=12) Diet (n=12) Diet+PA (n=12) Body mass (g) 30.2 ± 1.1 48.8 ± 0.5* 30.3 ± 0.7† 26.1 ± 0.3*,†,‡ HOMA-IR 22.9 ± 1.2 187.3 ± 7.5* 19.4 ± 8.8† 25.3 ± 10.5† IL-6 (pg/mL) 6.4 ± 0.7 6.2 ± 1.0 5.9 ± 0.9 6.4 ± 0.9 TNF-α (pg/mL) 30.8 ± 6.7 60.6 ± 5.3* 74.0 ± 8.1* 82.5 ± 7.7*,† IL-1β mRNA 1.00 ± 0.51 0.97 ± 0.34 1.20 ± 0.59 2.83 ± 0.62*,†,‡ IL-6 mRNA 1.00 ± 0.45 1.53 ± 0.50 1.16 ± 0.72 2.36 ± 0.55*,†,‡ TNF-α mRNA 1.00 ± 0.09 0.89 ± 0.08 0.94 ± 0.14 0.83 ± 0.06 TGF-β1 mRNA 1.00 ± 0.06 1.02 ± 0.06 1.02 ± 0.10 0.84 ± 0.05† Note. Data are presented as mean ± SEM. *Significantly (P\u3c0.05) different than LFD; †significantly (P\u3c0.05) different than HFD; ‡significantly (P\u3c0.05) different than Diet

    Bounds on the Magnetic Fields in the Radiative Zone of the Sun

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    We discuss bounds on the strength of the magnetic fields that could be buried in the radiative zone of the Sun. The field profiles and decay times are computed for all axisymmetric toroidal Ohmic decay eigenmodes with lifetimes exceeding the age of the Sun. The measurements of the solar oblateness yield a bound <~ 7 MG on the strength of the field. A comparable bound is expected to come from the analysis of the splitting of the solar oscillation frequencies. The theoretical analysis of the double diffusive instability also yields a similar bound. The oblateness measurements at their present level of sensitivity are therefore not expected to measure a toroidal field contribution.Comment: 15 pages, 6 figure

    Turbulent Mixing in the Surface Layers of Accreting Neutron Stars

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    During accretion a neutron star (NS) is spun up as angular momentum is transported through its surface layers. We study the resulting differentially rotating profile, focusing on the impact this has for type I X-ray bursts. The predominant viscosity is likely provided by the Tayler-Spruit dynamo. The radial and azimuthal magnetic field components have strengths of ~10^5 G and ~10^10 G, respectively. This leads to nearly uniform rotation at the depths of interest for X-ray bursts. A remaining small shear transmits the accreted angular momentum inward to the NS interior. Though this shear gives little viscous heating, it can trigger turbulent mixing. Detailed simulations will be required to fully understand the consequences of mixing, but our models illustrate some general features. Mixing has the greatest impact when the buoyancy at the compositional discontinuity between accreted matter and ashes is overcome. This occurs at high accretion rates, at low spin frequencies, or may depend on the ashes from the previous burst. We then find two new regimes of burning. The first is ignition in a layer containing a mixture of heavier elements from the ashes. If ignition occurs at the base of the mixed layer, recurrence times as short as ~5-30 minutes are possible. This may explain the short recurrence time of some bursts, but incomplete burning is still needed to explain these bursts' energetics. When mixing is sufficiently strong, a second regime is found where accreted helium mixes deep enough to burn stably, quenching X-ray bursts. We speculate that the observed change in X-ray burst properties near one-tenth the Eddington accretion rate is from this mechanism. The carbon-rich material produced by stable helium burning would be important for triggering and fueling superbursts. (abridged)Comment: Accepted for publication in The Astrophysical Journal, 16 pages, 15 figure

    Diabetes mellitus in Addis Ababa, Ethiopia: admissions, complications and outcomes in a large referral hospital.

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    SETTING: The Black Lion Referral Hospital, Addis Ababa, Ethiopia. OBJECTIVE: To document indications for admission, complications and outcomes of patients with diabetes mellitus (DM) admitted between 2010 and 2013. DESIGN: A descriptive retrospective study using medical files. RESULTS: Of 8048 admissions, 523 (6.5%) had DM; of these, 418 medical records were retrieved: 301 (72%) patients had type 2 and 104 (28%) type 1 disease, with male sex (62%) and older age (median age 60 years) being features of type 2 disease. Main admission diagnoses for type 2 disease were diabetic foot ulcer (39%) and cardiovascular disease (21%); for type 1 disease, it was diabetic ketoacidosis (62%). Hypertension, neuropathy, nephropathy, retinopathy and diabetic foot accounted for 85% of the 756 existing complications. Overall in-patient mortality was 21%. Of the 89 deaths, 77 occurred among patients with type 2 disease; the main indications for admission were diabetic foot ulcer/gangrene and cardiovascular disease. CONCLUSION: DM, especially type 2 DM, is an important cause of admission to Ethiopia's largest referral hospital. Many patients had already developed disease-related complications at admission, and mortality was high. There is a need to improve awareness about and care for DM in Ethiopia
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