Lunar impact flashes from Geminids, analysis of luminous efficiencies and the flux of large meteoroids on Earth

We analyze lunar impact flashes recorded by our team during runs in December 2007, 2011, 2013 and 2014. In total, 12 impact flashes with magnitudes ranging between 7.1 and 9.3 in V band were identified. From these, 9 events could be linked to the Geminid stream. Using these observations the ratio of luminous energy emitted in the flashes with respect to the kinetic energy of the impactors for meteoroids of the Geminid stream is estimated. By making use of the known Geminids meteoroid flux on Earth we found this ratio to be 2.1x10$^{-3}$ on average. We compare this luminous efficiency with other estimations derived in the past for other meteoroid streams and also compare it with other estimations that we present here for the first time by making use of crater diameter measurements. We think that the luminous efficiency has to be revised downward, not upward, at least for sporadic impacts. This implies an increase in the influx of kilogram-sized and larger bodies on Earth that has been derived thus far through the lunar impact flash monitoring technique

QSAR and molecular docking modelling of anti-leishmanial activities of organic selenium and tellurium compounds

Leishmaniasis affects mainly rural areas and the poorest people in the world. A computational study of the antileishmanial activity of organic selenium and tellurium compounds was performed. The 3D structures of the compounds were optimized at the wb97xd/lanl2dz level and used in the quantitative structure-activity relationship (QSAR) analysis. The antileishmanial activity was measured by L. donovani β carbonic anhydrase inhibition (Ki) and the half-maximal inhibitory concentration (IC50) against L. infantum amastigotes. The dataset was divided into training (75%) and test sets (25%) by using a k-means clustering algorithm. For pKi prediction, model M3 with seven 3D topographic descriptors was characterized by the following statistical parameters: r 2 = 0.879, Q 2 LOO = 0.822, and Q 2 ext = 0.840. For pIC50 prediction, model M12 with six attributes was characterized by the following statistical parameters: r 2 = 0.907, Q 2 LOO = 0.824, and Q 2 ext = 0.795. Both models met all the requirements of Tropsha´s test, which implies predictions of pIC50 and pKi activities with high accuracy. Concomitantly, favourable interactions of the sulphonamide group with the Zn atom in the protein were revealed by the docking analysis

Impact of primary care nursing workforce characteristics on the control of high-blood pressure: A multilevel analysis

Objective: To determine the impact of Primary Health Care (PHC) nursing workforce characteristics and of the clinical practice environment (CPE) perceived by nurses on the control of high-blood pressure (HBP). Design: Cross-sectional analytical study. Setting: Administrative and clinical registries of hypertensive patients from PHC information systems and questionnaire from PHC nurses. Participants: 76 797 hypertensive patients in two health zones within the Community of Madrid, North- West Zone (NWZ) with a higher socioeconomic situation and South-West Zone (SWZ) with a lower socioeconomic situation, and 442 reference nurses. Segmented analyses by area were made due to their different socioeconomic characteristics. Primary outcome measure: Poor HBP control (adequate figures below the value 140/90 mm Hg) associated with the characteristics of the nursing workforce and selfperceived CPE. Results: The prevalence of poor HBP control, estimated by an empty multilevel model, was 33.5% (95% CI 31.5% to 35.6%). In the multilevel multivariate regression models, the perception of a more favourable CPE was associated with a reduction in poor control in NWZ men and SWZ women (OR=0.99 (95% CI 0.98 to 0.99)); the economic immigration conditions increased poor control in NWZ women (OR=1.53 (95% CI 1.24 to 1.89)) and in SWZ, both men (OR=1.89 (95% CI 1.43 to 2.51)) and women (OR=1.39 (95% CI 1.09 to 1.76)). In all four models, increasing the annual number of patient consultations was associated with a reduction in poor control (NWZ women: OR=0.98 (95% CI0.98 to 0.99); NWZ men: OR=0.98 (95% CI 0.97 to 0.99); SWZ women: OR=0.98 (95% CI 0.97 to 0.99); SWZ men: OR=0.99 (95% CI 0.97 to 0.99). Conclusions: A CPE, perceived by PHC nurses as more favourable, and more patient–nurse consultations, contribute to better HBP control. Economic immigration condition is a risk factor for poor HBP control. Health policies oriented towards promoting positive environments for nursing practice are neededThe results presented here form part of a study that has been funded partially with the First Prize for National Research in Nursing (12th edition) from Hospital Universitario Marqués de Valdecilla (Santander) in 2010

QoSatAr: a cross-layer architecture for E2E QoS provisioning over DVB-S2 broadband satellite systems

This article presents QoSatAr, a cross-layer architecture developed to provide end-to-end quality of service (QoS) guarantees for Internet protocol (IP) traffic over the Digital Video Broadcasting-Second generation (DVB-S2) satellite systems. The architecture design is based on a cross-layer optimization between the physical layer and the network layer to provide QoS provisioning based on the bandwidth availability present in the DVB-S2 satellite channel. Our design is developed at the satellite-independent layers, being in compliance with the ETSI-BSM-QoS standards. The architecture is set up inside the gateway, it includes a Re-Queuing Mechanism (RQM) to enhance the goodput of the EF and AF traffic classes and an adaptive IP scheduler to guarantee the high-priority traffic classes taking into account the channel conditions affected by rain events. One of the most important aspect of the architecture design is that QoSatAr is able to guarantee the QoS requirements for specific traffic flows considering a single parameter: the bandwidth availability which is set at the physical layer (considering adaptive code and modulation adaptation) and sent to the network layer by means of a cross-layer optimization. The architecture has been evaluated using the NS-2 simulator. In this article, we present evaluation metrics, extensive simulations results and conclusions about the performance of the proposed QoSatAr when it is evaluated over a DVB-S2 satellite scenario. The key results show that the implementation of this architecture enables to keep control of the satellite system load while guaranteeing the QoS levels for the high-priority traffic classes even when bandwidth variations due to rain events are experienced. Moreover, using the RQM mechanism the user’s quality of experience is improved while keeping lower delay and jitter values for the high-priority traffic classes. In particular, the AF goodput is enhanced around 33% over the drop tail scheme (on average)