Characterisation of extrasolar planetary transit candidates

The detection of transits is an efficient technique to uncover faint companions around stars. The full characterisation of the companions (M-type stars, brown dwarfs or exoplanets) requires high-resolution spectroscopy to measure properly masses and radii. With the advent of massive variability surveys over wide fields, the large number of possible candidates makes such a full characterisation impractical for all of them. We explore here a fast technique to pre-select the most promising candidates using either near-IR photometry or low resolution spectroscopy. We develop a new method based on the well-calibrated surface brightness relation along with the correlation between mass and luminosity for main sequence stars, so that not only giant stars can be excluded but also accurate effective temperatures and radii can be measured. The main source of uncertainty arises from the unknown dispersion of extinction at a given distance. We apply this technique to our observations of a sample of 34 stars extracted from the 62 low-depth transits identified by OGLE during their survey of some 10e5 stars stars in the Carina fields of the Galactic disc. We infer that at least 78% of the companions of the stars which are well characterised in this sample are not exoplanets. Stars OGLE-TR-105, OGLE-TR-109 and OGLE-TR-111 are the likeliest to host exoplanets and deserve high-resolution follow-up studies. OGLE-TR-111 was very recently confirmed as an exoplanet with M_planet = 0.53 +- 0.1 M_Jup (Pont et al. 2004), confirming the efficiency of our method in pre-selecting reliable planetary transit candidates.Comment: 31 pages, 17 figures. Astronomy & Astrophysics, in pres

Norovirus Infection and Disease in an Ecuadorian Birth Cohort: Association of Certain Norovirus Genotypes With Host FUT2 Secretor Status.

BACKGROUND: Although norovirus is the most common cause of gastroenteritis, there are few data on the community incidence of infection/disease or the patterns of acquired immunity or innate resistance to norovirus. METHODS: We followed a community-based birth cohort of 194 children in Ecuador with the aim to estimate (1) the incidence of norovirus gastroenteritis from birth to age 3 years, (2) the protective effect of norovirus infection against subsequent infection/disease, and (3) the association of infection and disease with FUT2 secretor status. RESULTS: Over the 3-year period, we detected a mean of 2.26 diarrheal episodes per child (range, 0-12 episodes). Norovirus was detected in 260 samples (18%) but was not found more frequently in diarrheal samples (79 of 438 [18%]), compared with diarrhea-free samples (181 of 1016 [18%]; P = .919). A total of 66% of children had at least 1 norovirus infection during the first 3 years of life, and 40% of children had 2 infections. Previous norovirus infections were not associated with the risk of subsequent infection. All genogroup II, genotype 4 (GII.4) infections were among secretor-positive children (P < .001), but higher rates of non-GII.4 infections were found in secretor-negative children (relative risk, 0.56; P = .029). CONCLUSIONS: GII.4 infections were uniquely detected in secretor-positive children, while non-GII.4 infections were more often found in secretor-negative children

Excavation at Aguas Buenas, Robinson Crusoe Island, Chile, of a gunpowder magazine and the supposed campsite of Alexander Selkirk, together with an account of early navigational dividers

Excavations were undertaken of a ruined building at Aguas Buenas, identified as an 18th-century Spanish gunpowder magazine. Evidence was also found for the campsite of an early European occupant of the island. A case is made that this was Alexander Selkirk, a castaway here from 1704 to 1709. Selkirk was the model for Defoe’s Robinson Crusoe. A detailed discussion is given of a fragment of copper alloy identifi ed as being from a pair of navigational dividers

Costo de flete de las exportaciones chilenas: 2000-2008

El costo de flete que enfrentan las exportaciones chilenas muestra una trayectoria creciente en el lapso 2000-2008, caracterizada por oscilaciones. Las cifras del primer semestre de 2008, medidas en términos reales, se acercan a los US$75/tonelada, mientras que en 2000 se ubicaban en torno a los US$50/tonelada. A partir de la influencia que ejerce el cobre, el sector más relevante de las exportaciones chilenas lo constituye el mineral, con un costo de flete que se ha más que duplicado en el período de estudio, aunque sigue siendo uno de los más bajos en nivel en comparación con el resto. En el caso de los bienes manufacturados, el aumento es cercano al 20% y sólo 2008 explica la mitad del incremento. En el sector agrícola, las exportaciones de fruta, que se realizan mediante condiciones especiales de temperatura, presentan el costo de flete más elevado, caracterizadas por un fuerte componente estacional. La composición de la canasta exportadora, el tipo de transporte usado y otros factores explican los resultados cuando se analizan individualmente países o grupo de ellos, por lo que éstos deben ser tenidos en cuenta si se efectúan análisis comparativos entre países. Incluso cuando se evalúa el flete de un mismo bien a destinos diversos, se encuentra que destinos geográficamente más cercanos pueden presentar fletes más altos. En las canastas a todos los destinos la minería y en especial el cobre, ocupan un papel central aunque se aprecian matices. Asia presenta una alta concentración en minería y el mayor incremento en el costo de flete. Unión Europea, un poco menos concentrada en minerales, también explica la evolución del flete por las exportaciones de alimentos procesados, celulosa, frutas frescas y productos químicos básicos, que se aprecian más estables. Menos concentrados se encuentran Estados Unidos que también concentra envíos en alimentos y que presenta una variación de fletes inferior a Europa. En Aladi, el costo de flete ha permanecido estable debido al comportamiento de los envíos de alimentos, celulosa, productos químicos y forestales. Finalmente, si se agrupa al sector exportador de acuerdo al monto exportado, los grandes exportadores, relacionados principalmente con ventas de commodities, enfrentan un costo de flete que es la mitad de lo incurrido por medianos y pequeños, que presentan canastas relativamente más heterogéneas.

Receding-horizon model predictive control for a three-phase VSI with an LCL filter

© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.This paper presents a Continuous Control Set Model Predictive Control with receding horizon for a threephase voltage source inverter with LCL filter, using a reduced model of the converter. The main advantages of using this reduced model is that an active damping can be achieved while the computational burden is reduced. Besides, in order to eliminate the model uncertainties, and also to achieve a zero steady state error, the proposed converter model includes an embedded integrator. Regarding the control scheme, a Kalman filter is used in order to estimate the three-phase currents without oscillation. The objective is to find the control signals vector that minimizes the error between the current and its reference. It is important to remark that the control signals obtained fromthe cost function can be used directly in a space vector modulator, without the use of additional controllers such as proportionalintegral or proportional-resonant. Compared with the Finite Control Set Model Predictive Control, the proposedmethod operates at fixed switching frequency without using any restriction in the cost function. Simulation and experimental results show that this proposalworks correctly even in case of grid harmonics and voltage sags.Peer ReviewedPostprint (author's final draft

End of life in patients with advanced non-curable cancer : patient considerations around the moment of death

Existe conocimiento limitado sobre pacientes colombianos con cáncer avanzado preferencias con respecto a sus momentos finales, lugar de muerte y deseos posteriores a la muerte. A Para comprender mejor estas preferencias, realizamos 23 entrevistas en profundidad con pacientes entre 28 y 78 años que reciben tratamiento en dos hospitales académicos y el Instituto Nacional del Cáncer. Si bien muchos participantes deseaban una muerte pacífica, pocos se sentían cómodos discutiendo directamente el tema de la muerte. Algunos participantes más jóvenes expresó interés en la eutanasia pero no había recibido ninguna orientación o apoyo. Si bien varios participantes prefirieron morir en el hogar, algunos expresaron el deseo de morir en un hospital debido a un mejor control de los síntomas. Además, cuando se habla de post-muerte deseos, algunos participantes expresaron frustración por no poder tener estos conversaciones con sus seres queridos y sus preferencias para los arreglos funerarios.Q3Q2There is limited knowledge regarding Colombian patients with advanced cancer preferences regarding their final moments, place of death, and post-death wishes. To better understand these preferences, we conducted 23 in-depth interviews with patients between the ages of 28 and 78 receiving treatment at two academic hospitals and the National Cancer Institute. While many participants desired a peaceful death, few were comfortable discussing the topic of death directly. Some younger participants expressed an interest in euthanasia but had not received any guidance or support. While several participants preferred a home death, some expressed a desire to die in a hospital due to better symptom control. Additionally, when discussing post-death wishes, some participants expressed frustration about being unable to have these conversations with their loved ones and their preferences for funeral arrangements.Revista Internacional - IndexadaS

Isolation and characterization of homokaryotic strains from the ligninolytic basidiomycete Ceriporiopsis subvermispora

Indexación: Scopus.Genetic analyses of the lignin-degrading fungus Ceriporiopsis subvermispora is complicated by a dikaryotic nuclear condition and the absence of spore forms. Previous investigations had identified a family of closely related sequences encoding manganese peroxidase (MnP), but the relationship between genes and allelic variants could not be experimentally established. Addressing this issue, homokaryotic derivatives of C. subvermipora strain FP105752 were isolated from regenerated protoplasts. Designated CsA and CsB, their homokaryotic nature was established by polymerase chain reaction amplification and sequence analysis of the allelic variants of three MnP genes. Isoelectrofocusing revealed fewer MnP isoenzymes in filtrates of homokaryon cultures relative to the parental strain. The homokaryotic strains will simplify genetic analyses, particularly the identification of new genes.https://academic-oup-com.recursosbiblioteca.unab.cl/femsle/article/199/1/91/55387

Vasoactive intestinal peptide gene polymorphisms, associated with its serum levels, predict treatment requirements in early rheumatoid arthritis

We previously reported that early arthritis (EA) patients with low vasoactive intestinal peptide (VIP) serum levels demonstrate a worse clinical disease course. In this study, we analysed whether variants in the VIP gene correlated with its serum levels and clinical EA parameters. The VIP gene was sequenced in patients with extremely high/low VIP levels, measured by enzyme immunoassay. Sixteen single nucleotide polymorphisms (SNPs) were diferentially distributed between both groups, which were subsequently genotyped in two patients’ sets. We observed that patients with rs688136 CC genotype showed higher VIP levels in both discovery (n=91; p=0.033) and validation populations (n=131; p=0.007). This efect was attenuated by the presence of minor alleles rs35643203 and rs12201140, which showed a clear trend towards low VIP level association (p=0.118 and p=0.049, respectively). Functional studies with miR-205-5p, which has a target site in the 3′ UTR close to rs688136, revealed a miRNA-mediated regulatory mechanism explaining the higher VIP gene expression in homozygous patients. Moreover, patients with an rs688136 CC genotype and no minor alleles of the other polymorphisms required less treatment (p=0.009). We concluded that the identifcation of polymorphisms associated with VIP serum levels would complement the clinical assessment of the disease severity in rheumatoid arthritis patients

Demographic parameters in the population of dogs and cats in human settlements of the district of Ventanilla, Callao-Peru

El estudio tuvo como objetivo determinar indicadores demográficos de la población de canes y gatos domésticos con dueño en asentamientos humanos del distrito de Ventanilla, Callao (Perú). Se realizó un muestreo por conglomerado para seleccionar los grupos poblacionales y un muestreo estratificado y sistemático para seleccionar las viviendas. La información fue recolectada mediante una encuesta. Se calcularon las características demográficas de la tenencia de canes y gatos, y la relación can:persona y gato:persona. El 61.9 y 40.0% de las viviendas poseían canes y gatos, respectivamente. El número de mascotas por vivienda fue de 1.8 para ambas especies. El número de crías en los canes fue de 4.3 y en gatos de 3.1. La tasa de supervivencia estimada de las crías fue de 56.2 ± 3.0% en canes y de 66.4 ± 3.9% en gatos. La esperanza de vida estimada fue de 4.21 ± 0.44 años en canes y de 2.64 ± 0.46 años en gatos. Se estimó que existía 1 can por cada 3.98 personas y 1 gato por cada 5.34 personas. El 23% de encuestados manifestó mantener canes vagabundos en el exterior de las viviendas. Se espera que la información ofrecida sirva a las autoridades de salud para planificar programas de control poblacional y tenencia responsable de animales de compañía en esta población.The study aimed to determine demographic indicators of the population of domestic dogs and cats with owner in human settlements in the district of Ventanilla, Callao (Peru). A cluster sampling was performed to select the population groups and a stratified and systematic sampling was used to select the dwellings. The information was collected through a survey. The demographic characteristics of dogs and cats, and the relation dog:person and cat:person was calculated. In total, 61.9 and 40.0% of the houses owned dogs and cats, respectively. The number of pets per household was 1.8 in both species. The number of offspring in dogs was 4.3 and in cats was 3.1. The estimated survival rate was 56.2 ± 3.0% for puppies and 66.4 ± 3.9% for kittens. The estimated life expectancy was 4.21 ± 0.44 years in dogs and 2.64 ± 0.46 years in cats. It was estimated that there were 1 dog per 3.98 persons and 1 cat per 5.34 persons. Twenty-three percent of respondents said they maintained stray dogs outside homes. It is expected that the information provided will serve health authorities to plan population control programs and responsible pet ownership in this population