Incorporating geostrophic wind information for improved space-time short-term wind speed forecasting

Accurate short-term wind speed forecasting is needed for the rapid development and efficient operation of wind energy resources. This is, however, a very challenging problem. Although on the large scale, the wind speed is related to atmospheric pressure, temperature, and other meteorological variables, no improvement in forecasting accuracy was found by incorporating air pressure and temperature directly into an advanced space-time statistical forecasting model, the trigonometric direction diurnal (TDD) model. This paper proposes to incorporate the geostrophic wind as a new predictor in the TDD model. The geostrophic wind captures the physical relationship between wind and pressure through the observed approximate balance between the pressure gradient force and the Coriolis acceleration due to the Earth's rotation. Based on our numerical experiments with data from West Texas, our new method produces more accurate forecasts than does the TDD model using air pressure and temperature for 1- to 6-hour-ahead forecasts based on three different evaluation criteria. Furthermore, forecasting errors can be further reduced by using moving average hourly wind speeds to fit the diurnal pattern. For example, our new method obtains between 13.9% and 22.4% overall mean absolute error reduction relative to persistence in 2-hour-ahead forecasts, and between 5.3% and 8.2% reduction relative to the best previous space-time methods in this setting.Comment: Published in at http://dx.doi.org/10.1214/14-AOAS756 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

Physiological functions should be considered as true end points of nutritional intervention studies

With the beginning of this millennium it has become fashionable to only follow ‘evidence-based' practices. This generally-accepted approach cruelly negates experience or intelligent interpretation of pathophysiology. Another problem is that the great ‘meta-analysts' of the present era only accept end points that they consider ‘hard'. In the metabolic and nutritional field these end points are infection-related morbidity and mortality, and all other end points are considered ‘surrogate'. The aim of this presentation is to prove that this claim greatly negates the contribution of more-fundamentally-oriented research, the fact that mortality has multifactorial causes, and that infection is a crude measure of immune function. The following problems should be considered: many populations undergoing intervention have low mortality, requiring studies with thousands of patients to demonstrate effects of intervention on mortality; nutrition is only in rare cases primary treatment, and in many populations is a prerequisite for survival rather than a therapeutic modality; once the effect of nutritional support is achieved, the extra benefit of modulation of the nutritional support regimen can only be modest; cost-benefit is not a valid end point, because the better it is done the more it will cost; morbidity and mortality are crude end points for the effect of nutritional intervention, and are influenced by many factors. In fact, it is a yes or no factor. In the literature the most important contributions include new insights into the pathogenesis of disease, the diminution of disease-related adverse events and/or functional improvement after therapy. In nutrition research the negligence of these end points has precluded the development and validation of functional end points, such as muscle, immune and cognitive functions. Disability, quality of life, morbidity and mortality are directly related to these functional variables. It is, therefore, of paramount importance to validate functional end points and to consider them as primary rather than surrogate end point

Profil clinique et filière de santé des Requérants-es d’asile Mineurs-es Non-Accompagnés-es (RMNA)

Objectifs Le but de l’étude est de comprendre le profil clinique global (santé somatique et psychique) et la filière de santé des RMNA arrivés sur sol vaudois (Suisse) en 2015 dans un setting de gatekeeping infirmier spécialisé. Méthode C’est une étude transversale et rétrospective basée sur les informations présentes dans les dossiers médicaux de 109 patients inclus. Les motifs de consultation et de référence ainsi que les diagnostics retenus ont été relevés et codés selon ICD-10 dans l’ensemble des consultations (y compris bilan de santé initial) pour une année de suivi. Résultats Notre échantillon est majoritairement masculin (87.2%), dont plus de 2/3 originaires d’Erythrée (39.4%) et d’Afghanistan (32.1%). 67.7% des RMNA ont été référés plus loin dans le système de santé par le gatekeeping infirmier, en particulier près de la moitié (45.4%) dans une unité interdisciplinaire de médecine de l’adolescence, dont 21.3% à la fois dans cette unité et d’autres structures. De plus, 46.8% des 109 RMNA se sont au moins une fois présentés dans d’autres structures sans référence. Au moins une problématique de santé mentale a été relevée chez 39.4% des patients, principalement des troubles fonctionnels (21.1%), de probables épisodes dépressifs (17.4%), des symptômes de PTSD (13.8 %), et des troubles du sommeil (12.8%). En termes de maladies infectieuses, il a fréquemment été diagnostiqué des infections respiratoires communautaires (43.1%), des cas de gale (20.2%), et d’abcès/furoncles cutanés (13.8%). Plus rarement on retrouve quelques tuberculoses actives (3.7%), hépatites B chroniques (2.8%), parasitoses intestinales (1.8%) et gastrites confirmées à Helicobacter pylori (1.8%). 4 Dans les maladies non-transmissibles, les problèmes traumatologiques (30.3%) et ophtalmologiques (25.7%) occupent une place importante. Finalement chez les femmes RMNA (12.8% de la population), nous retrouvons fréquemment des mutilations génitales (21.4%), des grossesses (21.4%) et avortements (14.3%). Conclusions Une approche intégrée privilégiant une bonne coordination entre les différents intervenants est nécessaire pour répondre adéquatement aux besoins de santé objectivement très importants des RMNA. Une attention particulière doit être apportée à la santé mentale

Overweight and obesity in a Swiss city: 10-year trends

Abstract Background Increased rates of overweight/obesity have been reported in recent years in developed countries. This population study of healthy subjects evaluated the changes in overweight/obesity prevalence in 2003, compared with 1993, and determined the association of age, sex and leisure-time activity with body mass index (BMI), fat-free mass index (FFMI) and fat mass index (FMI). Design Two transversal samples of convenience. Participants Healthy volunteers (1993, n=802; 2003, n=1631). Methods Fat-free mass was determined using the bioelectrical impedance multiple regression equation. Multivariable linear regression, including confounding variables (age, sex, leisure-time activity), was used to model the body composition evolution between the 1993 and the 2003 subjects. Results BMI and FMI were higher in 2003 than in 1993, P<0.001. FFMI was not higher in 2003 than in 1993, P=0.38. More subjects were overweight/obese in 2003 than in 1993 (27.5 versus 17.2%, chi-square P<0.001), and had a high FFMI (30.2 versus 21.8%, chi-square P<0.001) and high FMI (28.0 versus 20.3%, chi-square P<0.001). Multivariate linear regressions showed that leisure-time activity was negatively, and sex, age and inclusion year were positively associated with BMI, FFMI and FMI (the exception was a negative association with sex) (P<0.001). Conclusion Overweight prevalence increased between 1993 and 2003 in a Swiss city, and was associated with a higher fat mass. This observation remained statistically significant after adjustment for age, sex and leisure-time activit

Niacin-induced clotting factor synthesis deficiency with coagulopathy

Although coagulopathy is a well-known complication of severe niacin- induced hepatotoxic reaction, it is not found in patients with minimal aminotransferase level elevations. Three patients with significant clotting factor synthesis deficiency and coagulopathy (prothrombin times, >1.5 times control) from sustained-release niacin had only mild aminotransferase level elevations (1.5 to 2.0 times normal). In each case, protein deficiency, coagulopathy, and aminotransferase level elevation resolved promptly after withdrawal of niacin therapy. In one case, this syndrome recurred after rechallenge with sustained-release niacin, whereas the coagulopathy did not recur in a second patient rechallenged with crystalline niacin. Deficiency in protein synthesis, including coagulation factors, and coagulopathy are unrecognized complications of sustained-release niacin therapy. These cases indicate the need to measure prothrombin times routinely in patients who develop even mild aminotransferase level elevation while receiving sustained- release niacin therapy. These data are important in light of the increasing use of sustained-release niacin in the treatment of patients with lipid disorders

Les étudiant·e·s en médecine mènent une recherche dans La communauté. [Male/female medical students conduct research in the community]

Pendant quatre semaines, les étudiant(e)s en médecine de 3e année de l'Université de Lausanne mènent une enquête dans la communauté sur le sujet de leur choix. L'objectif de ce module est de faire découvrir aux futurs médecins les déterminants non biomédicaux de la santé, de la maladie et de l'exercice de la médecine : les styles de vie, les facteurs psychosociaux et culturels, l'environnement, les décisions politiques, les contraintes économiques, les questions éthiques, etc. Par groupes de cinq, les étudiant(e)s commencent par définir une question de recherche originale et en explorent la littérature scientifique. Leur travail de recherche les amène à entrer en contact avec le réseau d'acteurs de la communauté concernés, professionnels ou associations de patients dont ils analysent les rôles et influences respectives. Chaque groupe est accompagné par un(e) tuteur(trice), enseignant(e) de la Faculté de biologie et de médecine de l'Université de Lausanne. Les étudiant(e)s présentent la synthèse de leurs travaux pendant un congrès de deux jours à la fin du module. Quatre travaux parmi les plus remarquables ont été choisis pour être publiés dans la Revue Médicale Suisse et Primary Care

Rifampicin/Cotrimoxazole/Isoniazid Versus Mefloquine or Quinine + Sulfadoxine- Pyrimethamine for Malaria: A Randomized Trial

OBJECTIVES: Previous studies of a fixed combination including cotrimoxazole, rifampicin, and isoniazid (Cotrifazid) showed efficacy against resistant strains of Plasmodium falciparum in animal models and in small-scale human studies. We conducted a multicentric noninferiority trial to assess the safety and efficacy of Cotrifazid against drug-resistant malaria in Papua New Guinea. DESIGN: The trial design was open-label, block-randomised, comparative, and multicentric. SETTING: The trial was conducted in four primary care health facilities, two in urban and two in rural areas of Madang and East Sepik Province, Papua New Guinea. PARTICIPANTS: Patients of all ages with recurrent uncomplicated malaria were included. INTERVENTIONS: Patients were randomly assigned to receive Cotrifazid, mefloquine, or the standard treatment of quinine with sulfadoxine–pyrimethamine (SP). OUTCOME MEASURES: Incidence of clinical and laboratory adverse events and rate of clinical and/or parasitological failure at day 14 were recorded. RESULTS: The safety analysis population included 123 patients assigned to Cotrifazid, 123 to mefloquine, and 123 to quinine + SP. The Cotrifazid group experienced lower overall incidence of adverse events than the other groups. Among the efficacy analysis population (72 Cotrifazid, 71 mefloquine, and 75 quinine + SP), clinical failure rate (symptoms and parasite load) on day 14 was equivalent for the three groups (0% for Cotrifazid and mefloquine; 1% for quinine + SP), but parasitological failure rate (P. falciparum asexual blood-stage) was higher for Cotrifazid than for mefloquine or quinine + SP (9% [PCR corrected 8%] versus 0% and 3%, respectively [p = 0.02]). CONCLUSION: Despite what appears to be short-term clinical equivalence, the notable parasitological failure at day 14 in both P. falciparum and P. vivax makes Cotrifazid in its current formulation and regimen a poor alternative combination therapy for malaria

Plasmodium vivax and Mixed Infections Are Associated with Severe Malaria in Children: A Prospective Cohort Study from Papua New Guinea

In a study carried out in Papua New Guinea, Blaise Genton and colleagues show thatPlasmodium vivax is associated with severe malaria