23 research outputs found
On the evolution of environmental and mass properties of strong lens galaxies in COSMOS
Among the 100 strong lens candidates found in the COSMOS field, 20 with
redshifts in the range [0.34,1.13], feature multiple images of background
sources. Using the multi-wavelength coverage of the field and its spectroscopic
follow-up, we characterize the evolution with redshift of the environment and
of the dark-matter (DM) fraction of the lens galaxies. We present new redshift
of the strong lens candidates. The lens environment is characterized by the
projected 10 closest galaxies around each lens and by the number of galaxies
with a projected distance less than 1Mpc at the lens galaxy redshift. In both
cases, we perform similar measurements on a control sample of twin non-lens
early type galaxies (ETGs). In addition, we identify group members and field
galaxies in the X-ray and optical catalogs of galaxy groups. From those
catalogs, we measure the external shear contribution at the lens galaxy
positions. The systems are then modeled using a SIE plus the external shear due
to the groups. We observe that the average stellar mass of lens galaxies
increases with z and that the environment of lens galaxies is compatible with
that of the twins. During the lens modeling, we notice that, when let free, the
external shear points in a direction which is the mean direction of the
external shear due to groups and of the closest galaxy to the lens. We notice
that the DM fraction of the lens galaxies within the Einstein radius decreases
as the redshift increases. Given these, we conclude that, while the environment
of lens galaxies is compatible with that of non-lens ETGS, their mass
properties evolves significantly with redshift: it is still not clear whether
this advocates in favor of a stronger lensing bias toward massive objects at
high redshift or is simply representative of the high proportion of massive and
high stellar density galaxies at high redshift.Comment: Accepted for publication in A&A. Significant modifications in the
paper but similar conclusion
The Hubble Constant
I review the current state of determinations of the Hubble constant, which
gives the length scale of the Universe by relating the expansion velocity of
objects to their distance. There are two broad categories of measurements. The
first uses individual astrophysical objects which have some property that
allows their intrinsic luminosity or size to be determined, or allows the
determination of their distance by geometric means. The second category
comprises the use of all-sky cosmic microwave background, or correlations
between large samples of galaxies, to determine information about the geometry
of the Universe and hence the Hubble constant, typically in a combination with
other cosmological parameters. Many, but not all, object-based measurements
give values of around 72-74km/s/Mpc , with typical errors of 2-3km/s/Mpc.
This is in mild discrepancy with CMB-based measurements, in particular those
from the Planck satellite, which give values of 67-68km/s/Mpc and typical
errors of 1-2km/s/Mpc. The size of the remaining systematics indicate that
accuracy rather than precision is the remaining problem in a good determination
of the Hubble constant. Whether a discrepancy exists, and whether new physics
is needed to resolve it, depends on details of the systematics of the
object-based methods, and also on the assumptions about other cosmological
parameters and which datasets are combined in the case of the all-sky methods.Comment: Extensively revised and updated since the 2007 version: accepted by
Living Reviews in Relativity as a major (2014) update of LRR 10, 4, 200
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Evaluation of Information Sources in Plastic Surgery Decision-making
Background Today, patients can access a myriad of information sources regarding plastic surgery procedures prior to meeting with a surgeon. Despite their widespread use, the role of these sources in a patient's decision-making remains undefined. We hypothesized that the physician remains the key information source for patients making surgical decisions in plastic surgery, but that other sources may deliver important insights and prove helpful to varying degrees. We also explored motivations for this outside information search and any differences in perceived value among patients. Methods We administered a survey regarding various information sources to our breast reconstruction, reduction, and abdominoplasty patients. Responses were compared between surgery groups and demographic groups. Ordinal logistic regression analysis was used to determine the impact of patient characteristics on helpfulness rank of different sources. Results Survey results were obtained from 58 patients, of whom 10 (17.2%) had abdominoplasty, 35 (60.3%) breast reconstruction, and 13 (22.4%) breast reduction. The most popular information sources prior to the first surgical appointment were Internet searches (56.9%) and family/friends/other patients (39.7%). After the initial appointment, the most useful sources were plastic surgeons (84.5%), and the Internet (36.2%). Most patients (73.5%) still sought outside information after their appointment. On a Likert-type scale of helpfulness, plastic surgeons ranked 4.28/5, followed by the web-based patient education platform, 3.73 and the Internet, 3.6. A total of 63% of participants listed plastic surgeons as their single most important source of information. In ordinal logistic regression analysis, non-white race was significantly associated with higher rank of surgeon helpfulness (p < 0.05). Relative to low-income patients, income 50-100k (p < 0.05) and 100k+ (p < 0.05) were associated with lower rank of surgeon helpfulness. Conclusions Most patients seek outside information prior to visiting with a surgeon from the Internet, social media, or family and friends. Patients consider plastic surgeons their most valuable information source overall, though still in need of supplementation for varying reasons. Additionally, certain demographic differences affect patient perception of information sources, and this is an important factor for surgeons to consider as they approach educating patients
Quando o silêncio é rompido: o processo de revelação e notificação de abuso sexual infantil When the silence is broken: the process of disclosure and reporting of child sexual abuse
O objetivo deste artigo é discutir o processo de revelação e notificação de situações de abuso sexual envolvendo crianças e adolescentes, a partir da análise de publicações relacionadas a essa temática. Os estudos indicam que a revelação e a notificação do abuso sexual são momentos difíceis para a vítima e para seus familiares porque geralmente envolvem alguém próximo à criança e apresentam reflexos no sistema familiar, como rompimento de vínculo, culpabilização e perda de suporte financeiro. Vários fatores que podem facilitar ou inibir a revelação e notificação do abuso são discutidos, como, por exemplo, a reação materna. Destaca-se a importância de um trabalho integrado no atendimento às vítimas, no encaminhamento das questões judiciais e no fortalecimento da rede de apoio às famílias.<br>The aim of this article is to discuss the process of disclosure and reporting of cases of sexual abuse involving children and adolescents, based on the analysis of publications related to that topic. Studies suggest that the disclosure and reporting of sexual abuse is a difficult moment for the victims and their families because it usually involves someone close to the child. It provokes changes in the family system, such as disruption of ties, guilt and loss in financial support. Several factors that may facilitate or inhibit the disclosure and reporting of sexual abuse are discussed such as the mother's reaction. It is highlighted the importance of an integrated work in the service that deals with these situations, involving the victims care, in the forwarding of the processes and in the strengthening of the supporting network for families
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ExoFiT: ExoMars-Like Field Trials – a Mission Simulation.
International audienceHere, we focus on the ExoMars-Like Field Trial (ExoFiT), a series of realistic mission simulations based on the ESA ExoMars rover mission slated to be launched in 2020. The mission will carry a suite of instruments to carry out its mission objectives focused on geological and exobiological researc