209 research outputs found
The SSS phase of RS Ophiuchi observed with Chandra and XMM-Newton I.: Data and preliminary Modeling
The phase of Super-Soft-Source (SSS) emission of the sixth recorded outburst
of the recurrent nova RS Oph was observed twice with Chandra and once with
XMM-Newton. The observations were taken on days 39.7, 54.0, and 66.9 after
outburst. We confirm a 35-sec period on day 54.0 and found that it originates
from the SSS emission and not from the shock. We discus the bound-free
absorption by neutral elements in the line of sight, resonance absorption lines
plus self-absorbed emission line components, collisionally excited emission
lines from the shock, He-like intersystem lines, and spectral changes during an
episode of high-amplitude variability. We find a decrease of the oxygen K-shell
absorption edge that can be explained by photoionization of oxygen. The
absorption component has average velocities of -1286+-267 km/s on day 39.7 and
of -771+-65 km/s on day 66.9. The wavelengths of the emission line components
are consistent with their rest wavelengths as confirmed by measurements of
non-self absorbed He-like intersystem lines. We have evidence that these lines
originate from the shock rather than the outer layers of the outflow and may be
photoexcited in addition to collisional excitations. We found collisionally
excited emission lines that are fading at wavelengths shorter than 15A that
originate from the radiatively cooling shock. On day 39.5 we find a systematic
blue shift of -526+-114 km/s from these lines. We found anomalous He-like f/i
ratios which indicates either high densities or significant UV radiation near
the plasma where the emission lines are formed. During the phase of strong
variability the spectral hardness light curve overlies the total light curve
when shifted by 1000sec. This can be explained by photoionization of neutral
oxygen in the line of sight if the densities of order 10^{10}-10^{11} cm^{-3}.Comment: 16 pages, 10 figures, 4 tables. Accepted by ApJ; v2: Co-author
Woodward adde
An XMM-Newton Study of the Bright, Nearby Supernova Remnant G296.1-0.5
We present a detailed study of the supernova remnant G296.1-0.5, performed
using observations with the EPIC and RGS instruments of the XMM-Newton
satellite. G296.1-0.5 is a bright remnant that displays an incomplete
multiple-shell morphology in both its radio and X-ray images. We use a set of
observations towards G296.1-0.5, from three distinct pointings of EPIC, in
order to perform a thorough spatial and spectral analysis of this remnant, and
hence determine what type of progenitor gave rise to the supernova explosion,
and describe the evolutionary state of the SNR. Our XMM-Newton observations
establish that the spectral characteristics are consistent across the X-ray
bright regions of the object, and are best described by a model of the emission
from a nonequilibrium ionization collisional plasma. The study reveals that the
emission from the shell is characterized by an excess of N and an
underabundance of O, which is typical of wind material from red supergiant
(RSG) and Wolf-Rayet (WR) stars. Additionally, we have detected transient X-ray
source 2XMMi J115004.8-622442 at the edge of the SNR whose properties suggest
that it is the result of stellar flare, and we discuss its nature in more
detail.Comment: 10 pages, 7 figures, 3 tables. Accepted for publication in Ap
Aplicación de la clasificación ATC al análisis de las prescripciones en DAMSU : I : los grupos de medicamentos que encabezan el ranking
Este es un estudio sobre utilización de medicamentos donde se analiza la evolución
de la prescripción, en DAMSU de UNCuyo, de los 14 grupos terapéuticos (GT) de la
clasificación ATC, durante 4 años consecutivos. Su objetivo fue determinar la
prevalencia de las prescripciones en los 3 primeros niveles de la clasificación. Los
datos fueron recolectados en los meses de abril, junio, setiembre y diciembre
utilizando la metodología del DURG y procesados con un programa EPI INFO. Las
comparaciones estadísticas fueron realizadas mediante la Prueba no paramétrica de
los Signos. El ranking de GT fue constante pero el total de prescripciones disminuyó
significativamente entre 2004 y 2007. Los GT del 1º nivel: S. Nervioso (N), S.
cardiovascular (C), Digestivo y Metabolismo (A) y Músculo-esquelético (M), ocuparon,
en orden decreciente, los cuatro primeros puestos del ranking durante los 4 años. De
estos GT fueron analizados los subgrupos del 2º y 3º nivel. La prescripción de
Psicolépticos + Psicoanalépticos superó a la de Analgésicos en el grupo N. En el
grupo C los Agentes Antihipertensivos, y entre ellos los IECAs, encabezaron el
ranking. Las vitaminas fueron las primeras en el GT A y el subgrupo de
Antiinflamatorios y Antirreumáticos en el GT M. Se discuten estos resultados en
función de la racionalidad de las prescripciones.This is a drug utilization research on the evolution of drug prescription in DAMSU of
UNCuyo, during 4 consecutive years, comprising the 14 therapeutic groups (TG) of
the ATC classification. The object was to determine the prescription prevalence in the
3 first levels of this classification. Data from April, June, September and December
were collected according to the DURG methodology and processed by an EPI INFO
program. Statistic comparisons were done with the nonparametric Signs Test. The TG
ranking was constant but the total drug prescription lowered significantly between
2004 and 2007. Four TG at the first level were: Nervous S. (N), Cardiovascular S. (C),
Digestive and Metabolism (A) and Muscle-Squeletal (M) shared in a decreasing order
the first 4 places of the ranking in the 4 scored years. From these TG the 2º and 3º
subgroups were analyzed. In the TG N the prescription of psychodrugs (Psycholeptics
+ Psychoanaleptics) was higher than that of Analgesics. In the TG C the Antihipertensive Agents, among which the ACEIs drugs are, did head the ranking.
Vitamins were the first in the TG A and the subgroup of Anti-inflammatory and Antirheumatics headed the TG M. Results are discussed in terms of rationality of
prescriptions.Fil: Sacchi, O. J..
Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Departamento de PatologíaFil: Kaiser, L. D..
Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Departamento de PatologíaFil: Riestra, E. C..
Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Departamento de PatologíaFil: Rodríguez, C. I..
Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Departamento de PatologíaFil: Zapata, M. P..
Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Departamento de PatologíaFil: Rodríguez Echandía, Eduardo.
Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Departamento de Patologí
Influence of roughness on conoscopic holography digitizing of DIN34CrMo4 surfaces
AbstractConoscopic Holography is a non-contact digitizing technique used in inspection and reverse engineering tasks. A laser beam is projected onto a surface, and its reflection generates a holographic pattern inside the sensor. This pattern is later analysed and the distance between sensor and surface is calculated. Like other optical techniques, conoscopic holography shall be affected by surface properties and ambient conditions. This works deals with the influence of surface roughness and manufacturing process on the quality of digitizing. 34CrMo4 steel test specimens have been manufactured to obtain four different Ra levels. Two different manufacturing process, electrical discharge machining (EDM) and ball-end milling (BEM) have been also considered. Quality of the digitized point clouds under different sensor configurations has been analysed, in order to provide a recommendation for optimal capture conditions
Paralichthys isosceles
This demersal species occurs from southern Brazil to Argentina and is taken in multi-species commercial´s fisheries that target demersal fishes through much of its range. It is a relatively minor component of the catch of Paralichthys species as compared to catch of the sympatric P. patagonicus. For purposes of this assessment, half of the global population is considered to occur in Brazil and the other half in Uruguay and Argentina. According to landings and catch per unit effort data, the demersal fish stocks of Brazil are inferred to have declined by at least 30% and possibly to 50%. Due to the lack of specific data for this species, an estimate for population decline is not available or cannot be suspected at this time. According to stock assessment and fisheries data, there is no decline detected in the demersal stock in Argentina and Uruguay and abundance indices show an increase in recent years (since 2014). Fishing effort continues at an unsustainable level in Brazil, the fishery is not well-monitored and conservation measures are insufficient. Conservation measures in Argentina and Uruguay include a total allowable catch limit and regular monitoring of stock status. Based on the potential major threat from overfishing in at least half of its global population, but lack of quantified data, it is listed as Data Deficient with a recommendation to improve fisheries monitoring, including the collection of species-specific data, as" "well as implement conservation measures to reduce effort in Brazilian fisheries.Fil: Riestra, C.. Instituto Nacional de Investigaciones y Desarrollo Pesquero; ArgentinaFil: Díaz de Astarloa, Juan Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Vieira, J. P.. Universidade Federal do Rio Grande do Sul; BrasilFil: Buratti, C.. Instituto Nacional de Investigaciones y Desarrollo Pesquero; ArgentinaFil: Irigoyen, A.. No especifíca;Fil: Landaeta, M.. Universidad de Valparaíso; ChileFil: Hüne, M.. Universidad Austral de Chile; Chil
Patagonotothen ramsayi
This species has a relatively small range on the continental shelf and slope of the southern part of the Patagonia Sea where it plays an important ecological role as a prey item for larger marine species. The majority of its global population is concentrated in southern Argentina, including the Malvinas Islands, where the main fishing ground is located. One generation length is estimated as 10 years. It is relatively slow-growing and late to maturity with relatively low fecundity, which may cause it to be susceptible to declines when facing heavy fishing pressure. Previous to 2006, it was mostly discarded as bycatch in large quantities beginning in the 1980s. A large-scale, commercial fishery began in 2007 in the Malvinas area. In areas outside the Malvinas closer to the Argentine mainland, it is taken in fisheries in relatively small amounts. According to stock assessment models based on catch per unit effort data and fishery independent trawl surveys, the estimated biomass for the period of 2005 to 2018 was highest in 2005 and then declined by 79% to a low in 2018. According to the 2019 and 2020 survey results, biomass has continued to decline. Biomass trends prior to 2005 are poorly understood, but based on these data, it is suspected that its population has declined by 40-50% on a global-level over the past one and a half generation lengths, or 15 years. In addition, declines in length at maturity and average length of individuals in the survey catch have also occurred. The cause of decline is poorly understood, but may be attributed in part to fishing activity or a shift in the spatial distribution of its abundance to areas adjacent to the Malvinas. Several fishery management measures are in place, catches have been at a relatively low level and it is not considered overfished. Due to the uncertainty associated with the cause of decline and lack of data prior to 2005, it is not possible to estimate the population trend to cover a three generation length period (either in the past or into the future) at this time. It is listed as Data Deficient with a strong recommendation to conduct studies to improve the understanding of this decline both within the Malvinas area and areas adjacent to it.Fil: Buratti, C.. Instituto Nacional de Investigaciones y Desarrollo Pesquero; ArgentinaFil: Díaz de Astarloa, Juan Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Hüne, M.. Universidad Austral de Chile; ChileFil: Irigoyen, A.. No especifíca;Fil: Landaeta, M.. Universidad de Valparaíso; ChileFil: Riestra, C.. Instituto Nacional de Investigaciones y Desarrollo Pesquero; ArgentinaFil: Vieira, J. P.. Universidade Federal Do Rio Grande.; Brasi
Acanthistius patachonicus, Patagonian Grouper
This rocky reef species has a relatively small range from southern Brazil to central Argentina. It is long- lived and the estimated generation length is 28.5 years. Large commercial fisheries targeted spawning aggregations of this species in the 1980s and 1990s until abundance steeply declined to the point where the market was no longer viable and at least four large areas where spawning aggregations were heavily depleted. Currently, it continues to be targeted by artisanal and industrial fisheries. The implementation of effective fishing area closures, both permanent and seasonal, in the El Rincón area is considered to provide a high level of protection for half of the global population of this species. According to fisher interviews, some level of population decline occurred within the past 40 years, or over a little more than one generation length ago. The lack of fisheries data, including a stock assessment, and the low level of understanding of the status of historical and current spawning aggregations prevents the estimation of percent population decline at this time. A secondary threat may be the reduction of habitat quality due to the invasive alga Undaria pinnatifida on shallow reefs, which has spread through much of its range. It is listed as Data Deficient with a strong recommendation to improve fishery monitoring and to conduct studies on spawning aggregations.Fil: Irigoyen, Alejo Joaquin. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Riestra, C.. Instituto Nacional de Investigaciones y Desarrollo Pesquero; ArgentinaFil: Buratti, C.. Instituto Nacional de Investigaciones y Desarrollo Pesquero; ArgentinaFil: Díaz de Astarloa, Juan Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Hüne, M.. Universidad Austral de Chile; ChileFil: Landaeta, M.. Universidad de Valparaíso; ChileFil: Vieira, J. P.. Universidade Federal Do Rio Grande.; Brasi
Sebastes oculatus, Patagonian Rockfish
This demersal, reef-associated species is common and abundant through much of its range. It is taken in fisheries at relatively low levels and may be impacted by invasive salmon. Global-level declines are not considered to be approaching a Near Threatened or threatened level at this time; therefore, it is listed as Least Concern.Fil: Buratti, C.. Instituto Nacional de Investigaciones y Desarrollo Pesquero; ArgentinaFil: Díaz de Astarloa, Juan Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Hüne, M.. Universidad Austral de Chile; ChileFil: Irigoyen, Alejo Joaquin. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Landaeta, M.. Universidad de Valparaíso; ChileFil: Riestra, C.. Instituto Nacional de Investigaciones y Desarrollo Pesquero; ArgentinaFil: Vieira, J. P.. Universidade Federal Do Rio Grande.; Brasi
- …