93 research outputs found

    Binaries discovered by the SPY project. IV, Five single-lined DA double white dwarfs

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    We present results from our ongoing follow-up observations of double white dwarf binaries detected in the ESO SN Ia Progenitor SurveY (SPY). We discuss our observing strategy and data analysis and present the orbital solutions of five close double white dwarf binaries: HE0320−1917, HE1511−0448, WD0326−273, WD1013−010 and WD1210+140. Their periods range from 0.44 to 3.22 days. In none of these systems we find any spectral lines originating from the companion. This rules out main sequence companions and indicates that the companion white dwarfs are significantly older and cooler than the bright component. Infrared photometry suggests the presence of a cool, helium-rich white dwarf companion in the binary WD 0326−273. We briefly discuss the consequences of our findings for our understanding of the formation and evolution of double white dwarfs

    Mapping technique of climate fields between GCM's and ice models

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    Here, we present a mapping method OBLIMAP, which projects and interpolates fields like surface temperature, surface mass balance, and surface height between a geographical based coordinate system of a General Circulation Model (GCM) and a rectangular based Ice Model (IM). We derive an oblique stereographic projection and its inverse, which holds for any area at the Earth's surface, and which can be combined with two different interpolation methods. The first one is suited to interpolate the projected fields of a coarse GCM grid on a fine meshed IM grid. The second one is appropriate for the opposite case. Both grids are allowed to be arbitrary and irregularly spaced. Therefore the OBLIMAP technique is suitable for any GCM-IM combination. After a first scan of the GCM grid coordinates and the specification of the IM grid, fast mapping of various fields is possible. To and fro (GCM-IM-GCM) mapping tests with the Climate Community System Model (CCSM) at T42 resolution (~313 km) and the Regional Atmospheric Climate Model (RACMO) at ~11 km and ~55 km, show average temperature differences of less than 0.1 K with small standard deviations. OBLIMAP, available at GMD, is an accurate, robust and well-documented mapping method for coupling an IM with a GCM or to map state of the art initial and forcing fields available at geographical coordinates to any local IM grid with an optimal centered oblique projection. Currently, the oblique stereographic and the oblique Lambert azimuthal equal-area projections for both the sphere and the ellipsoid are implemented in OBLIMAP

    Peculiar spectral and power spectral behaviour of the LMXB GX 13+1

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    We present results of an analysis of all 480 ks of Rossi X-ray Timing Explorer Proportional Counter Array data obtained from 17 May 1998 to 11 October 1998 on the luminous low mass X-ray binary GX 13+1. We analysed the spectral properties in colour-colour diagrams (CDs) and hardness-intensity diagrams (HIDs) and fitted the power spectra with a multi-Lorentzian model. GX 13+1 traces out a curved track in the CDs on a time scale of hours, which is very reminiscent of a standard atoll track containing an island, and lower and upper banana branch. However, both count rate and power spectral properties vary along this track in a very unusual way, not seen in any other atoll or Z source. The count rate, which varied by a factor of ~1.6, along a given track first decreases and then increases, causing the motion through the HIDs to be in the opposite sense to that in the CD, contrary to all other Z and atoll sources. Along a CD track, the very low frequency noise uniquely decreases in amplitude from ~5 to ~2% (rms). The high frequency noise amplitude decreases from ~4% to less than 1% and its characteristic frequency decreases from ~10 to \~5 Hz. The 57-69 Hz quasi-periodic oscillation (QPO) found earlier is also detected, and no kHz QPOs are found. In addition the entire track shows secular motion on a time scale of about a week. The average count rate as well as the amplitude of the very low frequency noise correlate with this secular motion. We discuss a possible explanation for the peculiar properties of GX 13+1 in terms of an unusual orientation or strength of a relativistic jet.Comment: 15 pages, 13 figures. Accepted for publication in A&

    EC-Earth3-AerChem: A global climate model with interactive aerosols and atmospheric chemistry participating in CMIP6

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    This paper documents the global climate model EC-Earth3-AerChem, one of the members of the EC-Earth3 family of models participating in the Coupled Model Intercomparison Project Phase 6 (CMIP6). EC-Earth3-AerChem has interactive aerosols and atmospheric chemistry and contributes to the Aerosols and Chemistry Model Intercomparison Project (AerChemMIP). In this paper, we give an overview of the model, describe in detail how it differs from the other EC-Earth3 configurations, and outline the new features compared with the previously documented version of the model (EC-Earth 2.4). We explain how the model was tuned and spun up under preindustrial conditions and characterize the model's general performance on the basis of a selection of coupled simulations conducted for CMIP6. The net energy imbalance at the top of the atmosphere in the preindustrial control simulation is on average -0.09 W m-2 with a standard deviation due to interannual variability of 0.25 W m-2, showing no significant drift. The global surface air temperature in the simulation is on average 14.08 ∼ C with an interannual standard deviation of 0.17 ∼ C, exhibiting a small drift of 0.015 ± 0.005 ∼ C per century. The model's effective equilibrium climate sensitivity is estimated at 3.9 ∼ C, and its transient climate response is estimated at 2.1 ∼ C. The CMIP6 historical simulation displays spurious interdecadal variability in Northern Hemisphere temperatures, resulting in a large spread across ensemble members and a tendency to underestimate observed annual surface temperature anomalies from the early 20th century onwards. The observed warming of the Southern Hemisphere is well reproduced by the model. Compared with the ECMWF (European Centre for Medium-Range Weather Forecasts) Reanalysis version 5 (ERA5), the surface air temperature climatology for 1995-2014 has an average bias of -0.86 ± 0.05 ∼ C with a standard deviation across ensemble members of 0.35 ∼ C in the Northern Hemisphere and 1.29 ± 0.02 ∼ C with a corresponding standard deviation of 0.05 ∼ C in the Southern Hemisphere. The Southern Hemisphere warm bias is largely caused by errors in shortwave cloud radiative effects over the Southern Ocean, a deficiency of many climate models. Changes in the emissions of near-term climate forcers (NTCFs) have significant effects on the global climate from the second half of the 20th century onwards. For the SSP3-7.0 Shared Socioeconomic Pathway, the model gives a global warming at the end of the 21st century (2091-2100) of 4.9 ∼ C above the preindustrial mean. A 0.5 ∼ C stronger warming is obtained for the AerChemMIP scenario with reduced emissions of NTCFs. With concurrent reductions of future methane concentrations, the warming is projected to be reduced by 0.5 ∼ C

    Historical Changes and Reasons for Model Differences in Anthropogenic Aerosol Forcing in CMIP6

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    The Radiative Forcing Model Intercomparison Project (RFMIP) allows estimates of effective radiative forcing (ERF) in the Coupled Model Intercomparison Project phase six (CMIP6). We analyze the RFMIP output, including the new experiments from models that use the same parameterization for anthropogenic aerosols (RFMIP-SpAer), to characterize and better understand model differences in aerosol ERF. We find little changes in the aerosol ERF for 1970–2014 in the CMIP6 multi-model mean, which implies greenhouse gases primarily explain the positive trend in the total anthropogenic ERF. Cloud-mediated effects dominate the present-day aerosol ERF in most models. The results highlight a regional increase in marine cloudiness due to aerosols, despite suppressed cloud lifetime effects in that RFMIP-SpAer experiment. Negative cloud-mediated effects mask positive direct effects in many models, which arise from strong anthropogenic aerosol absorption. The findings suggest opportunities to better constrain simulated ERF by revisiting the optical properties and long-range transport of aerosols

    Immediate Outcome Indicators in Perioperative Care: A Controlled Intervention Study on Quality Improvement in Hospitals in Tanzania.

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    Outcome assessment is the standard for evaluating the quality of health services worldwide. In this study, outcome has been divided into immediate and final outcome. Aim was to compare an intervention hospital with a Continuous Quality Improvement approach to a control group using benchmark assessments of immediate outcome indicators in surgical care. Results were compared to final outcome indicators. Surgical care quality in six hospitals in Tanzania was assessed from 2006-2011, using the Hospital Performance Assessment Tool. Independent observers assessed structural, process and outcome quality using checklists based on evidence-based guidelines. The number of surgical key procedures over the benchmark of 80% was compared between the intervention hospital and the control group. Results were compared to Case Fatality Rates. In the intervention hospital, in 2006, two of nine key procedures reached the benchmark, one in 2009, and four in 2011. In the control group, one of nine key procedures reached the benchmark in 2006, one in 2009, and none in 2011. Case Fatality Rate for all in-patients in the intervention hospital was 5.5% (n = 12,530) in 2006, 3.5% (n = 21,114) in 2009 and 4.6% (n = 18,840) in 2011. In the control group it was 3.1% (n = 17,827) in 2006, 4.2% (n = 13,632) in 2009 and 3.8% (n = 17,059) in 2011. Results demonstrated that quality assurance improved performance levels in both groups. After the introduction of Continuous Quality Improvement, performance levels improved further in the intervention hospital while quality in the district hospital did not. Immediate outcome indicators appeared to be a better steering tool for quality improvement compared to final outcome indicators. Immediate outcome indicators revealed a need for improvement in pre- and postoperative care. Quality assurance programs based on immediate outcome indicators can be effective if embedded in Continuous Quality Improvement. Nevertheless, final outcome indicators cannot be neglected

    From papers to practices: district level priority setting processes and criteria for family planning, maternal, newborn and child health interventions in Tanzania

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    Contains fulltext : 97928.pdf (publisher's version ) (Open Access)ABSTRACT: BACKGROUND: Successful priority setting is increasingly known to be an important aspect in achieving better family planning, maternal, newborn and child health (FMNCH) outcomes in developing countries. However, far too little attention has been paid to capturing and analysing the priority setting processes and criteria for FMNCH at district level. This paper seeks to capture and analyse the priority setting processes and criteria for FMNCH at district level in Tanzania. Specifically, we assess the FMNCH actor's engagement and understanding, the criteria used in decision making and the way criteria are identified, the information or evidence and tools used to prioritize FMNCH interventions at district level in Tanzania. METHODS: We conducted an exploratory study mixing both qualitative and quantitative methods to capture and analyse the priority setting for FMNCH at district level, and identify the criteria for priority setting. We purposively sampled the participants to be included in the study. We collected the data using the nominal group technique (NGT), in-depth interviews (IDIs) with key informants and documentary review. We analysed the collected data using both content analysis for qualitative data and correlation analysis for quantitative data. RESULTS: We found a number of shortfalls in the district's priority setting processes and criteria which may lead to inefficient and unfair priority setting decisions in FMNCH. In addition, participants identified the priority setting criteria and established the perceived relative importance of the identified criteria. However, we noted differences exist in judging the relative importance attached to the criteria by different stakeholders in the districts. CONCLUSIONS: In Tanzania, FMNCH contents in both general development policies and sector policies are well articulated. However, the current priority setting process for FMNCH at district levels are wanting in several aspects rendering the priority setting process for FMNCH inefficient and unfair (or unsuccessful). To improve district level priority setting process for the FMNCH interventions, we recommend a fundamental revision of the current FMNCH interventions priority setting process. The improvement strategy should utilize rigorous research methods combining both normative and empirical methods to further analyze and correct past problems at the same time use the good practices to improve the current priority setting process for FMNCH interventions. The suggested improvements might give room for efficient and fair (or successful) priority setting process for FMNCH interventions

    The EC-Earth3 Earth system model for the Coupled Model Intercomparison Project 6

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    The Earth system model EC-Earth3 for contributions to CMIP6 is documented here, with its flexible coupling framework, major model configurations, a methodology for ensuring the simulations are comparable across different high-performance computing (HPC) systems, and with the physical performance of base configurations over the historical period. The variety of possible configurations and sub-models reflects the broad interests in the EC-Earth community. EC-Earth3 key performance metrics demonstrate physical behavior and biases well within the frame known from recent CMIP models. With improved physical and dynamic features, new Earth system model (ESM) components, community tools, and largely improved physical performance compared to the CMIP5 version, EC-Earth3 represents a clear step forward for the only European community ESM. We demonstrate here that EC-Earth3 is suited for a range of tasks in CMIP6 and beyond

    Motivation and job satisfaction among medical and nursing staff in a Cyprus public general hospital

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    <p>Abstract</p> <p>Background</p> <p>The objective of this study was to investigate how medical and nursing staff of the Nicosia General Hospital is affected by specific motivation factors, and the association between <it>job satisfaction </it>and <it>motivation</it>. Furthermore, to determine the motivational drive of socio-demographic and job related factors in terms of improving work performance.</p> <p>Methods</p> <p>A previously developed and validated instrument addressing four work-related motivators (<it>job attributes, remuneration, co-workers and achievements</it>) was used. Two categories of health care professionals, medical doctors and dentists (N = 67) and nurses (N = 219) participated and motivation and job satisfaction was compared across socio-demographic and occupational variables.</p> <p>Results</p> <p>The survey revealed that <it>achievements </it>was ranked first among the four main motivators, followed by <it>remuneration</it>, <it>co-workers </it>and <it>job attributes</it>. The factor <it>remuneration </it>revealed statistically significant differences according to gender, and hospital sector, with female doctors and nurses and accident and emergency (A+E) outpatient doctors reporting greater mean scores (p < 0.005). The medical staff showed statistically significantly lower job satisfaction compared to the nursing staff. Surgical sector nurses and those >55 years of age reported higher job satisfaction when compared to the other groups.</p> <p>Conclusions</p> <p>The results are in agreement with the literature which focuses attention to management approaches employing both monetary and non-monetary incentives to motivate health care professionals. Health care professionals tend to be motivated more by intrinsic factors, implying that this should be a target for effective employee motivation. Strategies based on the survey's results to enhance employee motivation are suggested.</p

    Development of paediatric quality of inpatient care indicators for low-income countries - A Delphi study

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    BACKGROUND: Indicators of quality of care for children in hospitals in low-income countries have been proposed, but information on their perceived validity and acceptability is lacking. METHODS: Potential indicators representing structural and process aspects of care for six common conditions were selected from existing, largely qualitative WHO assessment tools and guidelines. We employed the Delphi technique, which combines expert opinion and existing scientific information, to assess their perceived validity and acceptability. Panels of experts, one representing an international panel and one a national (Kenyan) panel, were asked to rate the indicators over 3 rounds and 2 rounds respectively according to a variety of attributes. RESULTS: Based on a pre-specified consensus criteria most of the indicators presented to the experts were accepted: 112/137(82%) and 94/133(71%) for the international and local panels respectively. For the other indicators there was no consensus; none were rejected. Most indicators were rated highly on link to outcomes, reliability, relevance, actionability and priority but rated more poorly on feasibility of data collection under routine conditions. There was moderate to substantial agreement between the two panels of experts. CONCLUSIONS: This Delphi study provided evidence for the perceived usefulness of most of a set of measures of quality of hospital care for children proposed for use in low-income countries. However, both international and local experts expressed concerns that data for many process-based indicators may not currently be available. The feasibility of widespread quality assessment and responsiveness of indicators to intervention should be examined as part of continued efforts to improve approaches to informative hospital quality assessment
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