Systematics in lensing reconstruction: Dark matter rings in the sky?

Non-parametric lensing methods are a useful way of reconstructing the lensing mass of a cluster without making assumptions about the way the mass is distributed in the cluster. These methods are particularly powerful in the case of galaxy clusters with a large number of constraints. The advantage of not assuming implicitly that the luminous matter follows the dark matter is particularly interesting in those cases where the cluster is in a non-relaxed dynamical state. On the other hand, non-parametric methods have several limitations that should be taken into account carefully. We explore some of these limitations and focus on their implications for the possible ring of dark matter around the galaxy cluster CL0024+17. We project three background galaxies through a mock cluster of known radial profile density and obtain a map for the arcs ($\theta$ map). We also calculate the shear field associated with the mock cluster across the whole field of view (3.3 arcmin). Combining the positions of the arcs and the two-direction shear, we perform an inversion of the lens equation using two separate methods, the biconjugate gradient, and the quadratic programming (QADP) to reconstruct the convergence map of the mock cluster. We explore the space of the solutions of the convergence map and compare the radial density profiles to the density profile of the mock cluster. When the inversion matrix algorithms are forced to find the exact solution, we encounter systematic effects resembling ring structures, that clearly depart from the original convergence map. Overfitting lensing data with a non-parametric method can produce ring-like structures similar to the alleged one in CL0024.Comment: 12 pages, 8 image

The Role of Agriculture in Aggregate Business Cycle Fluctuations

The agricultural sector has certain distinctive features over the business cycle: it is more volatile than and not positively correlated with the rest of the economy and its employment is counter-cyclical. Because of these features and even though the agricultural sector represents less than 2% of the U.S. economy, we show that agriculture plays an essential role in understanding aggregate business cycles. The inclusion of agriculture into standard business cycle analysis resolves the longstanding problems of the standard theory in matching the observed volatility of aggregate labor and the correlation of aggregate labor and productivity (the so called Dunlop-Tharshis observation). In addition, the role of agriculture in the economy can account for the substantial differences observed in business cycle patterns across countries. This novel implication of the model is consistent with the systematic relationship observed between business cycle patterns and the share of agriculture across countries. Our theory has two important implications. First, the model implies that as the size of the agricultural sector falls, business cycle properties across countries should converge. Second, the role of agriculture provides a simple, measurable, and contrastable explanation for the historical properties of aggregate business cycles documented by Backus and Kehoe (1992).Business Cycles, Agriculture, Two-sector Model.

Aggregate Employment Fluctuations and Agricultural Share

Differences in employment volatility and the correlation of employment with output across countries are often cited as examples of the limitation of standard real business cycle (RBC) theory to reproduce the observed labor market facts. These observations have lead researchers to argue for the necessity of Non-Walrasian features to reflect the labor institutions in European countries. In this paper, we show that the same labor market evidence is observed in regional economies with the same labor market institutions. We conjecture that differences in agricultural activity can generate the observed differences in labor market behavior. We show that a standard two-sector RBC model with agriculture and non-agriculture can account for the observed labor market facts. In particular, as the size of agricultural activity increases, aggregate employment volatility and the correlation between aggregate employment and output decrease. Moreover, contrary to the Non-Walrasian approach to business cycles, agricultural activity can account for the correlation between aggregate employment and output as reported by Danthine and Donaldson (1993) for Europe and the U.S.Business Cycles, Agriculture, Two-sector Model.

Decision-making in an emergency department: A nursing accountability model

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Introduction Nurses that work in an emergency department regularly care for acute patients in a fast-paced environment, being at risk of suffering high levels of burnout. This situation makes them especially vulnerable to be accountable for decisions they did not have time to consider or have been pressured into. Research objective The objective of this study was to find which factors influence ethical, legal and professional accountability in nursing practice in an emergency department. Research design Data were analysed, codified and triangulated using qualitative ethnographic content analysis. Participants and research context This research is set in a large emergency department in the Midlands area of England. Data was collected from 186 nurses using participant observation, 34 semi-structured interviews with nurses and ethical analysis of 54 applicable clinical policies Ethical considerations Ethical approval was granted by two research ethics committees and the National Health Service Health Research Authority. Results The main result was the clinical nursing accountability cycle model, which showed accountability as a subjective concept that flows between the nurse and the healthcare institution. Moreover, the relations amongst the clinical nursing accountability factors are also analysed to understand which factors affect decision-making. Discussion The retrospective understanding of the factors that regulate nursing accountability is essential to promote that both the nurse and the healthcare institution take responsibility not only for the direct consequences of their actions but also for the indirect consequences derived from previous decisions. Conclusion The decision-making process and the accountability linked to it are affected by several factors that represent the holistic nature of both entities, which are organised and interconnected in a complex grid. This pragmatic interpretation of nursing accountability allows the nurse to comprehend how their decisions are affected, while the healthcare institution could act proactively to avoid any problems before they happen

Planck/SDSS Cluster Mass and Gas Scaling Relations for a Volume-Complete redMaPPer Sample

Using Planck satellite data, we construct SZ gas pressure profiles for a large, volume-complete sample of optically selected clusters. We have defined a sample of over 8,000 redMaPPer clusters from the Sloan Digital Sky Survey (SDSS), within the volume-complete redshift region 0.100 < z < 0.325, for which we construct Sunyaev-Zel'dovich (SZ) effect maps by stacking Planck data over the full range of richness. Dividing the sample into richness bins we simultaneously solve for the mean cluster mass in each bin together with the corresponding radial pressure profile parameters, employing an MCMC analysis. These profiles are well detected over a much wider range of cluster mass and radius than previous work, showing a clear trend towards larger break radius with increasing cluster mass. Our SZ-based masses fall ~24% below the mass-richness relations from weak lensing, in a similar fashion as the "hydrostatic bias" related with X-ray derived masses. We correct for this bias to derive an optimal mass-richness relation finding a slope 1.22 +/- 0.04 and a pivot mass log(M_500/M_0)= 14.432 +/- 0.041, evaluated at a richness lambda=60. Finally, we derive a tight Y_500-M_500 relation over a wide range of cluster mass, with a power law slope equal to 1.72 +/- 0.07, that agrees well with the independent slope obtained by the Planck team with an SZ-selected cluster sample, but extends to lower masses with higher precision.Comment: 13 pages, 7 figure

Planck/SDSS Cluster Mass and Gas Scaling Relations for a Volume-Complete redMaPPer Sample

Using Planck satellite data, we construct SZ gas pressure profiles for a large, volume-complete sample of optically selected clusters. We have defined a sample of over 8,000 redMaPPer clusters from the Sloan Digital Sky Survey (SDSS), within the volume-complete redshift region 0.100 < z < 0.325, for which we construct Sunyaev-Zel'dovich (SZ) effect maps by stacking Planck data over the full range of richness. Dividing the sample into richness bins we simultaneously solve for the mean cluster mass in each bin together with the corresponding radial pressure profile parameters, employing an MCMC analysis. These profiles are well detected over a much wider range of cluster mass and radius than previous work, showing a clear trend towards larger break radius with increasing cluster mass. Our SZ-based masses fall ~24% below the mass-richness relations from weak lensing, in a similar fashion as the "hydrostatic bias" related with X-ray derived masses. We correct for this bias to derive an optimal mass-richness relation finding a slope 1.22 +/- 0.04 and a pivot mass log(M_500/M_0)= 14.432 +/- 0.041, evaluated at a richness lambda=60. Finally, we derive a tight Y_500-M_500 relation over a wide range of cluster mass, with a power law slope equal to 1.72 +/- 0.07, that agrees well with the independent slope obtained by the Planck team with an SZ-selected cluster sample, but extends to lower masses with higher precision.Comment: 13 pages, 7 figure

Methods for nurses to measure body composition

Among the methods available for assessing body composition, traditional methods like hydrodensitometry and skin-fold measurements are well known. In this review, we focus on the impedance and interactance methods, which use systems that are usually inexpensive, easily transportable and simple to operate. We also discuss the usefulness of dual energy X-ray absorptiometry, particularly for the measurement of fat distribution. Nurses need to be skilled in the use of the equipment and familiar with the techniques.Entre los métodos disponibles para la determinación de la composición corporal, los tradicionales como la hidrodensitometría y la valoración de pliegues corporales son bien conocidos. En esta revisión nos centramos en los métodos basados en la impedancia y en la interactancia, caracterizados por la utilización de equipos económicos, fáciles de transportar y manejar. También discutimos la utilidad de la absorciometría dual de rayos-X, particularmente para la determinación de la distribución de la grasa corporal. Es importante que el personal de enfermería adquiera competencias en el uso de estos equipamientos y también se familiarice con las técnicas descritas.Entre os métodos disponíveis para a determinação da composição corporal, os tradicionais, como a hidrodensitometria e a avaliação de pregas corporais, são bem conhecidos. Para esta revisão, centrou-se nos métodos baseados na impedância e a interactância, caracterizados pela utilização de equipamentos econômicos, fáceis de transportar e manobrar. Também discutiu-se a utilidade da absorciometria dual de raios X, especialmente para a determinação da distribuição da gordura corporal. É importante que o pessoal de enfermagem adquira conhecimentos sobre o uso desse equipamento, bem como que se familiarize com as técnicas descritas

Ethical, legal and professional accountability in emergency nursing practice: an ethnographic observational study

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Introduction Accountability in nursing practice is a concept that influences quality care, decision-making, safety standards and staff values. Therefore, understanding accountability and how it affects nursing practice could improve patient care and nurses’ working conditions. Aim The aim of this study was to find factors that influenced ethical, legal and professional accountability in emergency nursing practice. Methods A qualitative ethnographic approach using participant observation through convenience sampling was employed as the data collection method, while ethnographic content analysis was used for data analysis. Results The factors linked to nursing accountability found were classified into four main themes: daily dynamics, work environment evolution, customs and routines and bioethics principles’ application. Discussion The long-term effect of chronic high workload and crowding, which affects nursing accountability, could promote burnout in a junior ED workforce. Changes in the nurses’ working conditions need to be implemented to limit the workload to which an ED nurse is subjected to. Conclusion ED nurses have to manage their accountability in difficult situations regularly, which followed patterns of four main themes across the majority of situations. Nonetheless, all those factors were influenced by nursing workload, an ever-present factor that was always considered by ED nurses during decision-making

Identidad social de la mujer en el parto en Andalucía

Fecha de lectura de Tesis: 5 noviembre 2018.En la actualidad parecen convivir diferentes formas de abordar e interpretar el proceso de parto y la maternidad, que reflejan diferentes identidades sociales. Con esta investigación se pretende abordar el análisis de las identidades sociales de las mujeres que se van a convertir en madres a través del análisis de su decisión sobre el tipo de parto que deseaban, el sentido que otorgan al dolor en ese proceso y la valoración de su proceso de parto. Para alcanzar dicha meta se ha considerado necesario un enfoque de investigación multimétodo que dé cabida a diferentes aproximaciones metodologías, en este caso, la combinación de técnicas de investigación cualitativa y cuantitativa. Una metodología cuantitativa que posibilita realizar una revisión y explotación de datos y estadísticas oficiales de los partos principalmente en Andalucía. Así mismo, se han analizado las características sociodemográficas de las mujeres que son atendidas para un parto según demanden o no, la utilización de la anestesia epidural como medio para aliviar los dolores del trabajo de parto. Una metodología cualitativa utilizada para analizar los discursos, expectativas y demandas de las mujeres que han tenido un parto, a través de las entrevistas en profundidad y los grupos de discusión que se han realizado. Los análisis realizados han permitido conocer los discursos que las mujeres tienen en torno al ideal de parto, que están vinculados fundamentalmente a cada uno de los tipos de identidad social de la mujer que en la presente tesis doctoral se recogen. Estas identidades sociales de las mujeres en sus partos, contienen una estructura de significados reconocidos y compartidos colectivamente, que dan un sentido a su manera de entender el mundo y a sus acciones acercándose en mayor o menor medida a un tipo de identidad, que es particular y distintivo con respecto a las demás identidades sociales

Visibilización y lucha de las organizaciones afrodescendientes por el reconocimiento de sus derechos en Argentina entre los años 2000 y 2014

En este artículo analizaremos los elementos cardinales que posibilitaron a las organizaciones de afrodescendientes cobrar visibilidad y lograr el reconocimiento de sus derechos en Argentina, en el periodo 2000-2014. A partir de los cambios estructurales que afectaron el sistema internacional desde finales del siglo XX, paulatinamente se irá conformando un singular acercamiento entre Estados,  organizaciones de la sociedad civil y organismos internacionales. Las nuevas articulaciones favorecerán a grupos históricamente marginados y negados, como los afrodescendientes. En este marco, buscaremos reconocer los factores que permitieron al colectivo afrodescendiente visibilizarse y avanzar en la reparación y la promoción de sus derechos en Argentina. Sostenemos que en nuestro país alcanzaron estas metas debido a que los afrodescendientes se articularon en organizaciones nacionales que, a su vez, se vincularon al Estado nacional en el marco de una normativa internacional proactiva y promotora de los derechos humanos, sociales, culturales, políticos, cívicos, económicos y medio ambientales