Teaching “Embedded Operating Systems” using Raspberry Pi and Virtual Machines

Embedded systems design, implementation and programming is an important topic in many curricula of Computer Science and Computer Engineering. This paper describes the estructure of a course on Embedded Operating Systems included in the Degree in Computer Science at the University of Valladolid. The course core elements are the use of virtual machines and Raspberry Pi kits. Our experience shows that the topics covered and the project-based methodology lead to excellent results in terms of student progression.Universidad de Granada: Departamento de Arquitectura y Tecnología de Computadores; Vicerrectorado para la Garantía de la Calida

Modeling dust emission in PN IC 418

We investigated the infrared (IR) dust emission from PN IC 418, using a detailed model controlled by a previous determination of the stellar properties and the characteristics of the photoionized nebula, keeping as free parameters the dust types, amounts and distributions relative to the distance of the central star. The model includes the ionized region and the neutral region beyond the recombination front (Photodissociation region, or PDR), where the [OI] and [CII] IR lines are formed. We succeeded in reproducing the observed infrared emission from 2 to 200~\mm. The global energy budget is fitted by summing up contributions from big grains of amorphous carbon located in the neutral region and small graphite grains located in the ionized region (closer to the central star). Two emission features seen at 11.5 and 30~\mm are also reproduced by assuming them to be due to silicon carbide (SiC) and magnesium and iron sulfides (Mg$_x$Fe$_{1-x}$S), respectively. For this, we needed to consider ellipsoidal shapes for the grains to reproduce the wavelength distribution of the features. Some elements are depleted in the gaseous phase: Mg, Si, and S have sub-solar abundances (-0.5 dex below solar by mass), while the abundance of C+N+O+Ne by mass is close to solar. Adding the abundances of the elements present in the dusty and gaseous forms leads to values closer to but not higher than solar, confirming that the identification of the feature carriers is plausible. Iron is strongly depleted (3 dex below solar) and the small amount present in dust in our model is far from being enough to recover the solar value. A remaining feature is found as a residue of the fitting process, between 12 and 25~\mm, for which we do not have identification.Comment: Accepted for publication in Astronomy & Astrophysics. V2: adding reference

Latitudinal and seasonal egg-size variation of the anchoveta (Engraulis ringens) off the Chilean coast

The anchoveta Engraulis ringens is widely distributed along the eastern South Pacific (from 4° to 42°S; Serra et al., 1979) and it has also supported one of the largest fisheries of the world over the last four decades. However, there are few interpopulation comparisons for either the adult or the younger stages. Reproductive traits, such as fecundity or spawning season length, are known to vary with latitude for some fish species (Blaxter and Hunter, 1982; Conover, 1990; Fleming and Gross, 1990; Castro and Cowen, 1991), and latitudinal trends for some early life history traits, such as egg size and larval growth rates, have been reported for others clupeiforms and other fishes (Blaxter and Hempel, 1963; Ciechomski, 1973; Imai and Tanaka, 1987, Conover 1990, Houde 1989). However, there is no published information on potential latitudinal trends during the adult or the early life history of the anchoveta, even though this type of information may help in understanding recruitment variability, especially during recurring large scale events (such as El Niño or La Niña) that affect the entire species range

Review and Support of the Relationship between Alliance Competence and Alliance Orientation

This paper seeks to contribute to the understanding of the formation of strategic alliances among companies. Specifically, it seeks to understand the relationship between alliance competence (Lambe, Speakman & Hunt, 2002) and alliance orientation (Kandemir, Yaprak & Cavusgil, 2006), following some of the most important guidelines of the leading exponents of theories based on resources and dynamic capabilities.Once the concepts were developed we proceeded to establish a hypothesis that seeks to better understand the relationships between the constructs and how they interact to achieve alliances that are beneficial for the parties involved.In particular, the findings corroborate the proposed relationships, supporting a direct link between market orientation constructs and senior management commitment to the alliances, as well as the commitment of senior management and competencies for alliances. As a fundamental contribution to this work, a mediating role of the alliance orientation construct was also detected between the relationship of senior management commitment and alliance competence.Future research is proposed into the elements of the practical guidelines for alliances and the relationship of this construct with the others related to alliances and particularly to their performance

Efecto de la densidad de siembra sobre el rendimiento de la okra (Abelmoschus esculentus (L.) Moench), en el valle de Lerma, Salta, Argentina

La okra es una malvácea anual cultivada como hortaliza adaptada a climas tropicales y subtropicales. El manejo del cultivo es poco conocido en Salta y Argentina. El objetivo fue determinar la densidad de siembra más adecuada en el valle de Lerma evaluando su efecto sobre las componentes del rendimiento. Con un diseño de bloques completos al azar, con 12 réplicas, se compararon cuatro densidades de siembra de okra variedad Blue Sky que fueron 1, 2, 3 y 4 plantas por pozo, (T1, T2, T3 y T4), con filas a 70 cm y hoyos a 30 cm. Se sembró el 25/10/11 y la emergencia fue a los 21 días. Se cosecharon frutos inmaduros entre el 23/12/11 y el 28/03/12, con un tamaño entre 7-10 cm de largo. Se evaluó el nú- mero y peso total de frutos cosechados en todo el ciclo de producción y por fecha de cosecha. Para todas las variables analizadas, los menores valores promedio se observaron en T1, mientras que entre T2, T3 y T4, si bien se vio una tendencia en aumento, no existieron diferencias estadísticamente significativas. Por consiguiente y debido a la dificultad de conseguir la semilla en el país y por su alto costo, se recomienda sembrar dos semillas por pozo.Okra is an annual Malvaceae cultivated as a vegetable crop and adapted to tropical and subtropical climate. There is no much crop management information in Salta and Argentina. The goal of this research was to determine the best plant density in the Lerma valley, Salta, Argentina. Treatments were four okra plant populations, cultivar Blue Sky (1, 2, 3 and 4 plants per hill: T1, T2, T3 y T4) evaluating its effect on the yield components. Experimental design was a randomized complete block with 12 blocks. The experiment was sown on October 25, 2011 and seed emergency happen 21 days after sowing. Fruits were harvested at immature stage from 23/12/11 to 28/03/12, with a size length from 7 to 10 cm. The parameters measured were: number and total fruit weight harvested in the whole production cycle and for each harvest date. For all parameters analyzed, the lower average values were observed in T1, but there were not statiscally differences between T2, T3 and T4. Nevertheless, there was a growing trend, although not statistically significant. It is recommended to plant two seeds per well (8 plants·m-2), because off the seed costs and for the difficulty of getting them in the Argentina.Fil: Lozano, L.. Universidad Nacional de Salta. Facultad de Ciencias Naturales; ArgentinaFil: Tálamo, Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Salta. Instituto de Bio y Geociencias del Noroeste Argentino; Argentina. Universidad Nacional de Salta; ArgentinaFil: Galarce, M.. Universidad Nacional de Salta. Facultad de Ciencias Naturales; ArgentinaFil: Ruiz de los Llanos, R.. Universidad Nacional de Salta. Facultad de Ciencias Naturales; Argentin

Heteroclinic and Homoclinic Connections Between the Sun-Earth Triangular Points and Quasi-Satellite Orbits for Solar Observations

Investigation of new orbit geometries exhibits a very attractive behavior for a spacecraft to monitor space weather coming from the Sun. Several orbit transfer mechanisms are analyzed as potential alternatives to monitor solar activity such as a sub-solar orbit or quasi-satellite orbit and short and long heteroclinic and homoclinic connections between the triangular points L4 and L5 and the collinear point L3 of the CRTBP (circular restricted three-body problem) in the Sun-Earth system. These trajectories could serve as channels through where material can be transported from L5 to L3 by performing small maneuvers at the departure of the Trojan orbit. The size of these maneuvers at L5 is between 299 m/s and 730 m/s depending on the transfer time of the trajectory and does not need any deterministic maneuvers at L3. Our results suggest that material may also be transported from the Trojan orbits to quasi-satellite orbits or even displaced quasi-satellite orbits

Control of mucocutaneous leishmaniasis, a neglected disease: results of a control programme in Satipo Province, Peru.

Mucocutaneous leishmaniasis (MCL) is an important health problem in many rural areas of Latin America, but there are few data on the results of programmatic approaches to control the disease. We report the results of a control programme in San Martin de Pangoa District, which reports one of the highest prevalences of MCL in Peru. For 2 years (2001--2002), the technicians at the health post were trained in patient case management, received medical support and were supplied with antimonials. An evaluation after 2 years showed the following main achievements: better diagnosis of patients, who were confirmed by microscopy in 34% (82/240) of the cases in 2001 and 60% of the cases (153/254) in 2002; improved follow-up during treatment: 237 of 263 (90%) patients who initiated an antimonial therapy ended the full treatment course; improved follow-up after treatment: 143 of 237 (60%) patients who ended their full treatment were correctly monitored during the required period of 6 (cutaneous cases) or 12 (mucosal cases) months after the end of treatment. These achievements were largely due to the human and logistical resources made available, the constant availability of medications and the close collaboration between the Ministry of Health, a national research institute and an international non-governmental organization. At the end of this period, the health authorities decided to register a generic brand of sodium stibogluconate, which is now in use. This should allow the treatment of a significant number of additional patients, while saving money to invest in other facets of the case management

Synthesis and optical characterization of Er-doped bismuth titanate nanoparticles grown by sol-gel hydrothermal method

The Er-doped bismuth titanate (BiTiO, BIT) nanoparticles were synthesized by a combined sol-gel and hydrothermal method under a partial oxygen pressure of 30 bar. The composition and morphology were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Raman scattering. They showed pure and homogeneous spherical BIT nanoparticles with a size below the 30 nm. The incorporation of Er ions showed a strong decrease in the lattice parameters, as well as averaged particle size. The photoluminescence up-conversion (excitation wavelength =1480 nm) showed an enhancement of the infrared emission (980 nm) as Er concentration increased, achieving a maximum for 6% mol, while photoluminescence spectra (excitation wavelength =473 nm) showed a strong green emission (529 and 553 nm) with a maximum at 4% mol