An assessment for UAS depart and approach operations

Unmanned Aerial Systems (UAS) have great potential to be used in a wide variety of civil applications such as environmental applications, emergency situations, surveillance tasks and more. The development of Flight Control Systems (FCS) coupled with the availability of other Commercial Off-The Shelf (COTS) components is enabling the introduction of UAS into the civil market. The sophistication of existing FCS is also making these systems accessible to end users with little aeronautics expertise. However, much work remains to be done to deliver systems that can be properly integrated in standard aeronautical procedures used by manned aviation. In previous research advances have been proposed in the flight plan capabilities by offering semantically much richer constructs than those present in most current UAS autopilots. The introduced flight plan is organized as a set of stages, each one corresponding to a different flight phase. Each stage contains a structured collection of legs inspired by current practices in Area Navigation (RNAV). However, the most critical parts of any flight, the depart and approach operations in an integrated airspace remain mostly unexplored. This paper introduces an assessment of both operations for UAS operating in VFR and IFR modes. Problems and potential solutions are proposed, as well as an automating strategy that should greatly reduce pilot workload. Although th

Depart and approach procedures for UAS in a VFR environment

This paper assesses the depart and approach operations of Unmanned Aircraft Systems (UAS) in one of the most challenging scenarios: when flying under Visual Flight Rules (VFR). Inspired by some existing procedures for (manned) general aviation, some automatic and predefined procedures for UAS are proposed. Hence, standardized paths to specific waypoints close to the airport are defined for depart operations, just before starting the navigation phase. Conversely, and for the approach maneuvers, it is foreseen a first integration into a holding pattern near the landing runway (ideally above it) followed by a standard VFR airfield traffic pattern. This paper discusses the advantages of these operations which aim at minimizing possible conflicts with other existing aircraft while reducing the Pilot-in-Command workload. Finally, some preliminary simulations are shown where these procedures have been successfully tested with simulated surrounding traffic

¿Adelantan el diagnóstico de la diabetes tipo 2 los nuevos criterios de la Asociación Americana de Diabetes?

ObjetivoAnalizar el intervalo temporal entre la primera hiperglucemia basal ocasional (HBO) y el diagnóstico de diabetes mellitus tipo 2 (DM2) al aplicar los criterios de la OMS y de la Asociación Americana de Diabetes (ADA).DiseñoEstudio observacional, retrospectivo. Ámbito del estudio. Centro de atención primaria urbano.SujetosUn total de 104 pacientes con DM2, diagnosticados entre 1991 y 1995, con antecedentes de HBO.Mediciones o intervencionesEdad, género y otros factores de riesgo, fechas de la primera HBO (glucemia basal 3 110 mg/dl), del diagnóstico según criterios OMS (2 glucemias basales 3 140 mg/dl o 3 200 mg/dl a las 2 horas de la sobrecarga oral de glucosa [SOG]) y aplicando criterios ADA (2 glucemias basales 3 126 mg/dl) y los intervalos en meses entre ellas.ResultadosDe los 222 pacientes diagnosticados, 104 (47%) presentaban antecedentes de HBO. La edad en el momento del diagnóstico fue 60,8 años (DE, 10,1), siendo un 53% mujeres. En 51 casos (49%) se realizó SOG. La mediana (rango) del intervalo entre la primera HBO y el diagnóstico fue de 16 meses (0–101) en los que se realizó la SOG y de 45 (1–104) en los que no se practicó (p = 0,003). En estos últimos, los criterios ADA lo redujeron a 31 meses (0–97) (p < 0,001) y en 27 de ellos que no cumplían ambos criterios a la vez el intervalo fue de sólo 10 meses (0–93) (p < 0,001). Conclusiones. La no realización de la SOG comporta un retraso en el diagnóstico que puede ser contrarrestado con la aplicación de los criterios de la ADA.ObjectiveTo analyze the period of time between the first occasional fasting hyperglycaemia (OFH) and the diagnosis of type 2 diabetes mellitus (DM2), using the World Health Organization (WHO) criteria or the American Diabetes Association (ADA) criteria.DesignRetrospective, observational study.SettingUrban primary care centre.Subjects104 patients with DM2 diagnosed between 1991 and 1995 who had a previous OFH.MeasurementsAge, gender and other risk factors, dates of the first OFH (fasting plasma glucose 3 110 mg/dl), the diagnosis according to WHO criteria (2 fasting plasma glucose 3 140 mg/dl or 3 200 mg/dl two hours after the oral glucose test tolerance (OGTT)) or with the ADA criteria (2 fasting plasma glucose 3 126 mg/dl), and the intervals in months between them.ResultsOf the 222 diagnosed patients, 104 (47%) had previous OFH. Age at diagnosis was 60.8 (SD 10.1) and 53% were women. OGTT was performed in 51 cases (49%). The median (range) of the interval between the first OFH and diagnosis was 16 months (0–101) for those who were undertaken an OGTT, and 45 months (1–104) for those who were not (p = 0.003). In these last ones, ADA criteria reduced the interval to 31 months (0–97) (p < 0.001). In 27 of these patients who did not satisfy both criteria at the same time, ADA criteria reduced the interval to 10 months (0–93) (p < 0.001).ConclusionsNot performing the OGTT means a delay in diagnosis which can be countered by applying the ADA criteria

The role of extracellular matrix on liver stem cell fate: A dynamic relationship in health and disease

The liver stem cell niche is a specialized and dynamic microenvironment with biomechanical and biochemical characteristics that regulate stem cell behavior. This is feasible due to the coordination of a complex network of secreted factors, small molecules, neural, blood inputs and extracellular matrix (ECM) components involved in the regulation of stem cell fate (self-renewal, survival, and differentiation into more mature phenotypes like hepatocytes and cholangiocytes). In this review, we describe and summarize all the major components that play essential roles in the liver stem cell niche, in particular, growth factor signaling and the biomechanical properties of the ECM

Angle-resolved photoemission study and first principles calculation of the electronic structure of GaTe

The electronic band structure of GaTe has been calculated by numerical atomic orbitals density-functional theory, in the local density approximation. In addition, the valence-band dispersion along various directions of the GaTe Brillouin zone has been determined experimentally by angle-resolved photoelectron spectroscopy. Along these directions, the calculated valence-band structure is in good concordance with the valence-band dispersion obtained by these measurements. It has been established that GaTe is a direct-gap semiconductor with the band gap located at the Z point, that is, at Brillouin zone border in the direction perpendicular to the layers. The valence-band maximum shows a marked \textit{p}-like behavior, with a pronounced anion contribution. The conduction band minimum arises from states with a comparable \textit{s}- \textit{p}-cation and \textit{p}-anion orbital contribution. Spin-orbit interaction appears to specially alter dispersion and binding energy of states of the topmost valence bands lying at $\Gamma$. By spin-orbit, it is favored hybridization of the topmost \textit{p}$_z$-valence band with deeper and flatter \textit{p$_x$}-\textit{p$_y$} bands and the valence-band minimum at $\Gamma$ is raised towards the Fermi level since it appears to be determined by the shifted up \textit{p$_x$}-\textit{p$_y$} bands.Comment: 7 text pages, 6 eps figures, submitted to PR

Investigation of conduction band structure, electron scattering mechanisms and phase transitions in indium selenide by means of transport measurements under pressure

In this work we report on Hall effect, resistivity and thermopower measurements in n-type indium selenide at room temperature under either hydrostatic and quasi-hydrostatic pressure. Up to 40 kbar (= 4 GPa), the decrease of carrier concentration as the pressure increases is explained through the existence of a subsidiary minimum in the conduction band. This minimum shifts towards lower energies under pressure, with a pressure coefficient of about -105 meV/GPa, and its related impurity level traps electrons as it reaches the band gap and approaches the Fermi level. The pressure value at which the electron trapping starts is shown to depend on the electron concentration at ambient pressure and the dimensionality of the electron gas. At low pressures the electron mobility increases under pressure for both 3D and 2D electrons, the increase rate being higher for 2D electrons, which is shown to be coherent with previous scattering mechanisms models. The phase transition from the semiconductor layered phase to the metallic sodium cloride phase is observed as a drop in resistivity around 105 kbar, but above 40 kbar a sharp nonreversible increase of the carrier concentration is observed, which is attributed to the formation of donor defects as precursors of the phase transition.Comment: 18 pages, Latex, 10 postscript figure

Measuring performance of social and non-profit Microfinance Institutions (MFIs): An application of multicriterion methodology

Microfinance Institutions (MFIs) are special financial institutions of both social and nonprofit nature whose performance has been traditionally measured by means of financial ratios. However, performance rankings are usually based on a single criterion, so the performance measure varies according to the criterion used. This paper proposes a multicriterion methodology based on goal programming that simultaneously considers different categories involved in the performance of Microfinance Institutions. The paper is illustrated by a sample of Latin American MFIs.Bartual Sanfeliu, C.; Cervelló Royo, RE.; Moya Clemente, I. (2013). Measuring performance of social and non-profit Microfinance Institutions (MFIs): An application of multicriterion methodology. Mathematical and Computer Modelling. 57(7-8):1671-1678. doi:10.1016/j.mcm.2011.11.010S16711678577-