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A statistical model for sea surface diurnal warming driven by numercial weather predictions fluxes and winds
A statistical model is derived relating the diurnal variation of sea surface temperature (SST) to the net surface heat flux and surface wind speed from a numerical weather prediction (NWP) model. The model is derived using fluxes and winds from the European Centre for Medium-Range Weather Forecasting (ECMWF) NWP model and SSTs from the Spinning Enhanced Visible and Infrared Imager (SEVIRI). In the model, diurnal warming has a linear dependence on the net surface heat flux integrated since (approximately) dawn and an inverse quadratic dependence on the maximum of the surface wind speed in the same period. The model coefficients are found by matching, for a given integrated heat flux, the frequency distributions of the maximum wind speed and the observed warming. Diurnal cooling, where it occurs, is modelled as proportional to the integrated heat flux divided by the heat capacity of the seasonal mixed layer. The model reproduces the statistics (mean, standard deviation, and 95-percentile) of the diurnal variation of SST seen by SEVIRI and reproduces the geographical pattern of mean warming seen by the Advanced Microwave Scanning Radiometer (AMSR-E). We use the functional dependencies in the statistical model to test the behaviour of two physical model of diurnal warming that display contrasting systematic errors
Substituent position effects on sunscreen photodynamics : a closer look at methyl anthranilate
Towards the development of a bottom-up rationale for sunscreen design, the effects of substituent position on the ultrafast photodynamics of the sunscreen precursor methyl anthranilate (MA, an ortho compound) were evaluated by studying para- and meta-MA in vacuum. Time-resolved ion yield (TR-IY) measurements reveal a long-lived S1 excited state (≫ 1.2 ns) for para-MA, proposed to be the result of a weakly fluorescent, bound excited state. In the case of meta-MA, TR-IY transients reveal a much faster (∼2 ns) excited state relaxation, possibly due to multiple low-lying S1/S0 conical intersections of prefulvenic character. While meta-MA may not be an ideal sunscreen ingredient due to a low ultraviolet absorbance, its comparatively efficient relaxation mechanism may constitute an alternative to common sunscreen relaxation pathways. Thus, our results should prompt further studies of prefulvenic relaxation pathways in potential sunscreen agents
Diagnosis, clinical course, and 1-year outcome in patients hospitalized for heart failure with preserved ejection fraction (from the Polish Cohort of the European Society of Cardiology Heart Failure Long-Term Registry)
[Abstract] Compared with heart failure (HF) with reduced ejection fraction (HF-REF), the diagnosis of HF with preserved EF (HF-PEF) is more challenging. The aim of the study was to assess the prevalence of HF-PEF among patients hospitalized for HF, to evaluate the pertinence of HF-PEF diagnosis and to compare HF-PEF and HF-REF patients with respect to outcomes. The analysis included 661 Polish patients hospitalized for HF, selected from the European Society of Cardiology (ESC)-HF Long-Term Registry. Patients with an EF of ≥50% were included in the HF-PEF group and patients with an EF of <50% - in the HF-REF group. The primary end point was all-cause death at 1 year. The secondary end point was a composite of all-cause death and rehospitalization for HF at 1 year. HF-PEF was present in 187 patients (28%). Of those 187 patients, mitral inflow pattern was echocardiographically assessed in 116 patients (62%) and classified as restrictive/pseudonormal in 37 patients (20%). Compared with HF-REF subjects, patients with HF-PEF were older, more often female, and had a higher prevalence of hypertension, atrial fibrillation and sleep apnea. Despite lower B-type natriuretic peptide concentrations and lower prevalence of moderate-to-severe mitral regurgitation in patients with HF-PEF, congestive symptoms at admission were as severe as in patients with HF-REF. There were no significant differences in in-hospital mortality between the HF groups. One-year mortality was high in both groups (17% in HF-PEF vs 21% in HF-REF, p = 0.22). There was a trend toward a lower frequency of the secondary end point in the HF-PEF group (32% vs 40%, p = 0.07). In conclusion, in clinical practice, even easily obtainable echocardiographic indexes of diastolic dysfunction are relatively rarely acquired. One-year survival rate of patients with HF-PEF is not significantly better than that of patients with HF-REF
Validation of Aura Microwave Limb Sounder O-3 and CO observations in the upper troposphere and lower stratosphere
International audienceGlobal satellite observations of ozone and carbon monoxide from the Microwave Limb Sounder (MLS) on the EOS Aura spacecraft are discussed with emphasis on those observations in the 215–100 hPa region (the upper troposphere and lower stratosphere). The precision, resolution and accuracy of the data produced by the MLS “version 2.2” processing algorithms are discussed and quantified. O3 accuracy is estimated at ~40 ppbv +5% (~20 ppbv +20% at 215 hPa) while the CO accuracy is estimated at ~30 ppbv +30% for pressures of 147 hPa and less. Comparisons with expectations and other observations show good agreements for the O3 product, generally consistent with the systematic errors quoted above. In the case of CO, a persistent factor of ~2 high bias is seen at 215 hPa. However, the morphology is shown to be realistic, consistent with raw MLS radiance data, and useful for scientific study. The MLS CO data at higher altitudes are shown to be consistent with other observations
Anemia at hospital admission and its relation to outcomes in patients with heart failure (from the polish cohort of 2 European Society of Cardiology Heart Failure Registries)
[Abstract] Anemia is a commonly observed co-morbidity in heart failure (HF). The aim of the study was to assess prevalence, risk factors for, and effect of anemia on short- and long-term outcomes in HF. The study included 1,394 Caucasian patients hospitalized for HF, with known hemoglobin concentration on hospital admission, participating in 2 HF registries of the European Society of Cardiology (Pilot and Long-Term). Anemia was defined as hemoglobin concentration of <13 g/dl for men and <12 g/dl for women. Primary end points were (1) all-cause death at 1 year and (2) a composite of all-cause death and rehospitalization for HF at 1 year. Secondary end points included inter alia death during index hospitalization. In addition, we investigated the effect of changes in hemoglobin concentration during hospitalization on prognosis. Anemia occurred in 33% of patients. Predictors of anemia included older age, diabetes, greater New York Heart Association class at hospital admission and kidney disease. During 1-year follow-up, 21% of anemic and 13% of nonanemic patients died (p <0.0001). Combined primary end point occurred in 45% of anemic and in 33% of nonanemic patients (p <0.0001). Anemia was strongly predictive of all the prespecified clinical end points in univariate analyses but not in multivariate analyses. Changes in hemoglobin concentration during hospitalization had no effect on 1-year outcomes. In conclusion, anemia was present in 1/3 of patients with HF. Mild-to-moderate anemia seems more a marker of older age, worse clinical condition, and a higher co-morbidity burden, rather than an independent risk factor in HF
Effect of β-blockers on 1-year survival and hospitalizations in patients with heart failure and atrial fibrillation: results from ESC-HF pilot and ESC-HF long-term registry
[Abstract] Introduction The positive effect of β-blocker therapy in patients with heart failure (HF) and atrial fibrillation (AF) has been questioned.
Objectives We aimed to assess the effect of β-blockers and heart rate (HR) control on 1-year outcomes in patients with HF and AF.
Patients and methods Of the 2019 Polish patients enrolled in ESC-HF Pilot and ESC-HF Long-Term Registry, 797 patients with HF and AF were classified into 2 groups depending on β-blocker use. Additionally, patient survival was compared between 3 groups classified according to HR: lower than 80 bpm, between 80 and 109 bpm, and of 110 bpm or higher. The primary endpoint was all-cause death and the secondary endpoint was all-cause death or HF hospitalization.
Results In patients treated with β-blockers, the primary and secondary endpoints were less frequent than in patients not using β-blockers (10.9% vs 25.6%, P = 0.001 and 30.6% vs 44.2%, P = 0.02, respectively). Absence of β-blocker treatment was a predictor of both endpoints in a univariate analysis but remained an independent predictor only of the primary endpoint in a multivariate analysis (hazard ratio for β-blocker use, 0.52; 95% CI, 0.31–0.89; P = 0.02). The primary and secondary endpoints were more frequent in patients with a HR of 110 bpm or higher, but the HR itself did not predict the study endpoints in the univariate analysis.
Conclusions β-blocker use might decrease mortality in patients with HF and AF, but it seems to have no impact on the risk of HF hospitalization. An HR of 110 bpm or higher may be related to worse survival in these patients
Blood pressure and glaucoma: At the crossroads between cardiology and ophthalmology
Glaucoma is an optic nerve neuropathy of undetermined cause. Although many mechanisms are thought to be involved in the development and progression of the disease, only an increased intraocular pressure has been established as a clinically significant modifiable risk factor. Nevertheless, up to 40% of patients develop glaucoma without evidence of increased intraocular pressure.
Ample evidence suggests that alterations in the control of arterial blood might negatively affect optic nerve function. However, evidence-based guidelines on the management of arterial blood pressure in glaucoma patients are lacking. Regrettably, intraocular pressure is generally not included as a secondary end-point in clinical trials on arterial hypertension. Considering the relative simplicity of intraocular pressure measurements and large number of patients included in hypertension studies, the benefits of including intraocular pressure as a secondary end-point could be of a great value for improving care for glaucoma patients. Therefore, closer collaboration between cardiologists and ophthalmologists is needed.
Expiratory flow rate, breath hold and anatomic dead space influence electronic nose ability to detect lung cancer
BACKGROUND: Electronic noses are composites of nanosensor arrays. Numerous studies showed their potential to detect lung cancer from breath samples by analysing exhaled volatile compound pattern ("breathprint"). Expiratory flow rate, breath hold and inclusion of anatomic dead space may influence the exhaled levels of some volatile compounds; however it has not been fully addressed how these factors affect electronic nose data. Therefore, the aim of the study was to investigate these effects. METHODS: 37 healthy subjects (44 +/- 14 years) and 27 patients with lung cancer (60 +/- 10 years) participated in the study. After deep inhalation through a volatile organic compound filter, subjects exhaled at two different flow rates (50 ml/sec and 75 ml/sec) into Teflon-coated bags. The effect of breath hold was analysed after 10 seconds of deep inhalation. We also studied the effect of anatomic dead space by excluding this fraction and comparing alveolar air to mixed (alveolar + anatomic dead space) air samples. Exhaled air samples were processed with Cyranose 320 electronic nose. RESULTS: Expiratory flow rate, breath hold and the inclusion of anatomic dead space significantly altered "breathprints" in healthy individuals (p 0.05). These factors also influenced the discrimination ability of the electronic nose to detect lung cancer significantly. CONCLUSIONS: We have shown that expiratory flow, breath hold and dead space influence exhaled volatile compound pattern assessed with electronic nose. These findings suggest critical methodological recommendations to standardise sample collections for electronic nose measurements
‘Give courage to the ladies’: expansive apprenticeship for women in rural Malawi
Apprenticeship in developed and industrialised nations is increasingly understood as a theory of learning which connects workplace activity and formal study. The concept of ‘expansive apprenticeship’ defines frameworks for workforce development where participants acquire knowledge and skills which will help them in the future as well as in their current roles, whilst ‘restrictive’ apprenticeships limit opportunities for wider, lifelong learning. In developing nations apprenticeship is a traditional route to learning and employment, but apprenticeships in these contexts tend to reflect a restrictive approach characterized by narrowly defined roles and weak educational outcomes. This paper examines a project in Malawi which uses concepts of expansive apprenticeship to address barriers to female continuing education and chronic teacher shortages. The Malawi Access to Teaching Scholarship recruited one thousand women to follow a year-long combined programme of academic distance study and practical work experience in rural primary schools. The aim is to increase the numbers of women teachers in Malawi, especially in rural areas. The Scholarship materials and support structures are designed to move participants from restrictive to expansive contexts for learning so that Scholars develop hybrid roles as students, community workers and apprentice pedagogues. The programme’s resources and approach offer an innovative model of expansive apprenticeship in Sub Saharan Africa
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