918 research outputs found

    Predicting Avian Influenza Co-Infection with H5N1 and H9N2 in Northern Egypt.

    Get PDF
    Human outbreaks with avian influenza have been, so far, constrained by poor viral adaptation to non-avian hosts. This could be overcome via co-infection, whereby two strains share genetic material, allowing new hybrid strains to emerge. Identifying areas where co-infection is most likely can help target spaces for increased surveillance. Ecological niche modeling using remotely-sensed data can be used for this purpose. H5N1 and H9N2 influenza subtypes are endemic in Egyptian poultry. From 2006 to 2015, over 20,000 poultry and wild birds were tested at farms and live bird markets. Using ecological niche modeling we identified environmental, behavioral, and population characteristics of H5N1 and H9N2 niches within Egypt. Niches differed markedly by subtype. The subtype niches were combined to model co-infection potential with known occurrences used for validation. The distance to live bird markets was a strong predictor of co-infection. Using only single-subtype influenza outbreaks and publicly available ecological data, we identified areas of co-infection potential with high accuracy (area under the receiver operating characteristic (ROC) curve (AUC) 0.991)

    A framework for evaluating operations control on a metro line: integrating multiple perspectives and automatically collected train and passenger movement data

    Get PDF
    Transit operations control, the task of implementing the operations plan in daily operations on a metro line, plays a key role in service delivery because it determines the quality of the service experienced by passengers. Yet, it is one of the most poorly understood aspects of rail transit operations. Faced with a disruption or infeasibility, dispatchers typically choose between several response strategies. However, to date, it has been very difficult to evaluate the positive and negative effects of individual control strategies with respect to operations and passenger travel times under real-world conditions. This paper proposes a framework for the study of rail operations control decisions that integrates automatically collected service and passenger demand data, which are increasingly available and accessible to transit agencies. The framework supports a multiperspective analysis methodology that can inform operational policies and plans, and help operations control decision-makers choose the most appropriate strategies to manage service. By using automatically collected data, taking into consideration the operations control decision environment, and acknowledging that the reliability of the resulting service depends on many factors endogenous to it, this paper takes a distinctly different approach from previous studies, which have relied heavily on modeling, assumed simple operating contexts, and did not consider the full range of available data. Two real-world applications of the framework, where control decisions are evaluated in terms of their operational and passenger impacts, are presented. The methodology is found to be versatile and valuable in providing insights that could not have been gained otherwise. Although the framework is applied to the London Underground, its logic, structure, and procedures are applicable and transferable to other metro systems recognizing that certain specifics would need to be tailored to the available data.Transport for London (Organization

    Variabilité à long terme des peuplements de poissons : résultats provenant de rivières françaises et ouest africaines

    Get PDF
    La variabilité à long terme de 18 peuplements de poissons a été étudiée dans des rivières françaises et ouest africaines. Les principaux résultats sont les suivants : 1) le coefficient de variation (CV) de la richesse spécifique, le CV de l'abondance totale et le CV moyen des espèces constitutives du peuplement augmentent avec la durée de l'étude; 2) selon la classification proposée par GROSSMAN et al. (1990) basée sur le CV moyen de l'abondance des espèces, tous les peuplements étudiés rentrent dans la catégorie des peuplements à fortes fluctuations interannuelles. Cependant certaines populations (les salmonidés en Bretagne par exemple) présentent une faible variabilité de leur densité; 3) dans le Rhône, les peuplements dont les populations manifestent une grande variabilité interannuelle sont ceux présentant le plus grand taux de renouvellement en espèces. Ce résultat est en accord avec l'hypothèse de HORWITZ (1978, "extermination hypothesis"). (Résumé d'auteur

    High-accuracy mass measurements of neutron-rich Kr isotopes

    Get PDF
    The atomic masses of the neutron-rich krypton isotopes 84,86-95Kr have been determined with the tandem Penning trap mass spectrometer ISOLTRAP with uncertainties ranging from 20 to 220 ppb. The masses of the short-lived isotopes 94Kr and 95Kr were measured for the first time. The masses of the radioactive nuclides 89Kr and 91Kr disagree by 4 and 6 standard deviations, respectively, from the present Atomic-Mass Evaluation database. The resulting modification of the mass surface with respect to the two-neutron separation energies as well as implications for mass models and stellar nucleosynthesis are discussed

    Benefit of early commencement of growth hormone therapy in children with Prader-Willi syndrome

    Get PDF
    Prader-Willi syndrome (PWS) is a chromosomal disorder and growth failure is a common presentation. Growth hormone (GH) treatment is beneficial in PWS although the optimal age for starting GH is unknown. We investigated whether GH response in PWS was associated with the age of GH commencement by comparing 16 children who commenced GH before 3 years of age (early group) with 40 children who commenced GH after 3 years of age (late group) from the Ozgrow database. Height SDS, body mass index (BMI) SDS, bone age (BA)-chronological age (CA) ratio, change in height (Delta Ht) SDS and change in BMI during 4 years of GH treatment were compared between the groups. The early group had better height SDS and Delta Ht SIDS. BA delay was more pronounced in the early group but BA did not mature beyond CA with GH therapy in either group. Although the initial GH dose for the early group was lower than that of the late group, the former had better height outcome. The starting GH dose seen in the database is lower than the dose used by international centres

    Coronary artery disease severity and aortic stenosis: clinical outcomes according to SYNTAX score in patients undergoing transcatheter aortic valve implantation

    Get PDF
    Aim The aim of this study was to evaluate whether coronary artery disease (CAD) severity exerts a gradient of risk in patients with aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI). Methods and results A total of 445 patients with severe AS undergoing TAVI were included into a prospective registry between 2007 and 2012. The preoperative SYNTAX score (SS) was determined from baseline coronary angiograms. In case of revascularization prior to TAVI, residual SS (rSS) was also determined. Clinical outcomes were compared between patients without CAD (n = 158), patients with low SS (0-22, n = 207), and patients with high SS (SS >22, n = 80). The pre-specified primary endpoint was the composite of cardiovascular death, stroke, or myocardial infarction (MI). At 1 year, CAD severity was associated with higher rates of the primary endpoint (no CAD: 12.5%, low SS: 16.1%, high SS: 29.6%; P = 0.016). This was driven by differences in cardiovascular mortality (no CAD: 8.6%, low SS: 13.6%, high SS: 20.4%; P = 0.029), whereas the risk of stroke (no CAD: 5.1%, low SS: 3.3%, high SS: 6.7%; P = 0.79) and MI (no CAD: 1.5%, low SS: 1.1%, high SS: 4.0%; P = 0.54) was similar across the three groups. Patients with high SS received less complete revascularization as indicated by a higher rSS (21.2 ± 12.0 vs. 4.0 ± 4.4, P 14) was associated with higher rates of the primary endpoint at 1 year (no CAD: 12.5%, low rSS: 16.5%, high rSS: 26.3%, P = 0.043). Conclusions Severity of CAD appears to be associated with impaired clinical outcomes at 1 year after TAVI. Patients with SS >22 receive less complete revascularization and have a higher risk of cardiovascular death, stroke, or MI than patients without CAD or low S

    Perioperative infusion of low- dose of vasopressin for prevention and management of vasodilatory vasoplegic syndrome in patients undergoing coronary artery bypass grafting-A double-blind randomized study

    Get PDF
    Preoperative medication by inhibitors of angiotensin-converting enzyme (ACE) in coronary artery patients predisposes to vasoplegic shock early after coronary artery bypass grafting. Although in the majority of the cases this shock is mild, in some of them it appears as a situation, "intractable" to high-catecholamine dose medication. In this study we examined the possible role of prophylactic infusion of low-dose vasopressin, during and for the four hours post-bypass after cardiopulmonary bypass, in an effort to prevent this syndrome. In addition, we studied the influence of infused vasopressin on the hemodynamics of the patients, as well as on the postoperative urine-output and blood-loss. In our study 50 patients undergoing coronary artery bypass grafting were included in a blind-randomized basis. Two main criteria were used for the eligibility of patients for coronary artery bypass grafting: ejection fraction between 30-40%, and patients receiving ACE inhibitors, at least for four weeks preoperatively. The patients were randomly divided in two groups, the group A who were infused with 0.03 IU/min vasopressin and the group B who were infused with normal saline intraoperativelly and for the 4 postoperative hours. Measurements of mean artery pressure (MAP), central venous pressure (CVP), systemic vascular resistance (SVR), ejection fracture (EF), heart rate (HR), mean pulmonary artery pressure (MPAP), cardiac index (CI) and pulmonary vascular resistance (PVR) were performed before, during, and after the operation. The requirements of catecholamine support, the urine-output, the blood-loss, and the requirements in blood, plasma and platelets for the first 24 hours were included in the data collected. The incidence of vasodilatory shock was significantly lower (8% vs 20%) in group A and B respectively (p = 0,042). Generally, the mortality was 12%, exclusively deriving from group B. Postoperatively, significant higher values of MAP, CVP, SVR and EF were recorded in the patients of group A, compared to those of group B. In group A norepinephrine was necessary in fewer patients (p = 0.002) and with a lower mean dose (p = 0.0001), additive infusion of epinephrine was needed in fewer patients (p = 0.001), while both were infused for a significant shorter infusion-period (p = 0.0001). Vasopressin administration (for group A) was associated with a higher 24 hour diuresis) (0.0001)

    Stratégies démographiques des poissons des rivières françaises : premiers résultats

    Full text link
    International audienceThe analysis of the biological, morphological and food characteristics of 35 French species leads to distinguish two main strategies. The first one gathers 11 species with a short life span and which maximize the survival of juveniles. Within it, cold water species with a long reproduction lifetime and thermophilous species with a relatively stronger fertility can be distinguished. Their diets are essentially made of insects- plankton and insects-fishes. In the second group, no care is given to juveniles; relative fertilities are higher and inversely correlated to the number of reproduction cycles. 10 species are omnivorous with a grass-wastes tendancy, and 4 species eat strictly fishes. The canonical analysis of correspondances shows that these biological characteristics are sufficuent to understand most of the longitudinal zonation.L'analyse des caractéristiques biologiques et morpho-alimentaires de 35 espèces françaises permet de distinguer 2 stratégies principales. La première rassemble 11 espèces à faible longévité et maximisant la survie des jeunes. En son sein, on distingue des espèces d'eau froide à longue durée de vie pré-reproductrice et des espèces thermophiles à fécondité relativement plus forte. Leurs régimes alimentaires sont essentiellement du type insectivore-planctonophage et insectivore-ichtyophage. Dans le second groupe, aucun soin n'est apporté aux jeunes ; les fécondités relatives sont plus fortes et inversement corrélées avec le nombre de cycles de reproduction. 10 espèces sont des omnivores à tendance herbivore-détritivore et 4 des ichtyophages stricts. L'analyse canonique des correspondances démontre que ces caractéristiques biologiques rendent compte de l'essentiel de la zonation longitudinale

    Surgery for anomalous aortic origin of coronary arteries : a multicentre study from the European Congenital Heart Surgeons Association

    No full text
    OBJECTIVES: We sought to describe early and late outcomes in a large surgical series of patients with anomalous aortic origin of coronary arteries. METHODS: We performed a retrospective multicentre study including surgical patients with anomalous aortic origin of coronary arteries since 1991. Patients with isolated high coronary takeoff and associated major congenital heart disease were excluded. RESULTS: We collected 156 surgical patients (median age 39.5 years, interquartile range 15-53) affected by anomalous right (67.9%), anomalous left (22.4%) and other anatomical abnormalities (9.6%). An interarterial course occurred in 86.5%, an intramural course in 62.8% and symptoms in 85.9%. The operations included coronary unroofing (56.4%), reimplantation (19.2%), coronary bypass graft (15.4%) and other (9.0%). Two patients with preoperative cardiac failure died postoperatively (1.3%). All survivors were discharged home in good clinical condition. At a median follow-up of 2 years (interquartile range 1-5, 88.5% complete), there were 3 deaths (2.2%), 9 reinterventions in 8 patients (5 interventional, 3 surgical); 91.2% are in New York Heart Association functional class <= II, but symptoms persisted in 14.2%; 48.1% of them returned to sport activity. On Kaplan-Meier analysis, event-free survival at follow-up was 74.6%. Morbidity was not significantly different among age classes, anatomical variants and types of surgical procedures. Furthermore, return to sport activity was significantly higher in younger patients who participated in sports preoperatively. CONCLUSIONS: Surgical repair of anomalous aortic origin of coronary arteries is effective and has few complications. Unroofing and coronary reimplantation are safe and are the most common procedures. The occurrence of late adverse events is not negligible, and long-term surveillance is mandatory. Most young athletes can return to an unrestrained lifestyle
    • …
    corecore