Gendered Habitus in Engineering: Experiences of Brazilian Students

This paper discusses the ways in which an ‘engineering habitus’, that in the first instance presents itself as a predominantly masculinized habitus - because its inclinations, competences and dispositions are homologous to the cultural repertoire traditionally associated with men – may change with the growing presence of women in the field. We draw from the perspective advanced by Bourdieu, in particular the key notions of habitus, capital and field, to explore how particular competences, dispositions and classificatory principles operate in the field of engineering. The study is based on qualitative in-depth analysis of the socialization trajectories of 10 students (five men and five women) enrolled in an engineering degree in a publicly-funded Brazilian university, as well as on quantitative secondary data about the students. This is placed in broader national and international contexts. The socialization trajectories of both women and men studying engineering demonstrate that the experiences of women are patterned by a double bind in cultural repertoires, which affect traditional associations with gender. An engineering gendered habitus not conforming to the stereotypical and dominant masculine is in evidence, as women not only develop competences and dispositions homologous to the traditional masculine habitus, but also show inclinations and affinities commonly associated with femininity. The study advances the hypothesis that the growing participation of women in engineering drives this process, challenging traditional gender divisions and propelling a more flexible gendered engineering habitus in the field. We propose that the phenomenon discussed here deserves further investigation

Spectrum of the Anomalous Microwave Emission in the North Celestial Pole with WMAP 7-Year data

We estimate the frequency spectrum of the diffuse anomalous microwave emission (AME) on the North Celestial Pole (NCP) region of the sky with the Correlated Component Analysis (CCA) component separation method applied to WMAP 7-yr data. The NCP is a suitable region for this analysis because the AME is weakly contaminated by synchrotron and free-free emission. By modeling the AME component as a peaked spectrum we estimate the peak frequency to be $21.7\pm0.8$\,GHz, in agreement with previous analyses which favored $\nu_{\rm p}<23$\,GHz. The ability of our method to correctly recover the position of the peak is verified through simulations. We compare the estimated AME spectrum with theoretical spinning dust models to constrain the hydrogen density $n_{\rm H}$. The best results are obtained with densities around 0.2--0.3\,cm$^{-3}$, typical of warm ionised medium (WIM) to warm neutral medium (WNM) conditions. The degeneracy with the gas temperature prevents an accurate determination of $n_{\rm H}$, especially for low hydrogen ionization fractions, where densities of a few cm$^{-3}$ are also allowed.Comment: 13 pages, 6 figures, published in Advances in Astronom

Foreground removal for Square Kilometre Array observations of the Epoch of Reionization with the Correlated Component Analysis

We apply the Correlated Component Analysis (CCA) method on simulated data of the Square Kilometre Array, with the aim of accurately cleaning the 21 cm reionization signal from diffuse foreground contamination. The CCA has been developed for the Cosmic Microwave Background, but the application of the Fourier-domain implementation of this method to the reionization signal is straightforward. The CCA is a parametric method to estimate the frequency behaviour of the foregrounds from the data by using second-order statistics. We test its performance on foreground simulations of increasing complexity, designed to challenge the parametric models adopted. We also drop the assumption of spectral smoothness that most of the methods rely upon. We are able to clean effectively the simulated data across the explored frequency range (100-200 MHz) for all the foreground simulations. This shows that the CCA method is very promising for EoR component separation.Comment: 12 pages, 15 figures, accepted by MNRA

Identification problems in the solution of linearized DSGE models

This article analyzes identification problems that may arise while linearizing and solving DSGE models. A criterion is proposed to determine whether or not a set of parameters is partially identifiable, in the sense of Canova and Sala (2009), based on the computation of a basis for the null space of the Jacobian matrix of the function mapping the parameters with the coefficients in the solution of the model.Parameter identification, DSGE models Classification JEL:C13, C51, C52, E32

A CHARACTERIZATION OF HOMOGENEOUS PRODUCTION FUNCTIONS

This paper states a theorem that characterizes homogeneous production functions in terms of the ratio of average to marginal costs. The theorem claims that a production function is homogeneous of degree k if and only if the ratio of average costs to marginal costs is constant and equal to k. In order to prove the theorem two lemmas -with theoretical value of their own- are demonstrated before hand: the first one establishes that a production function is homogeneous of degree k if and only if its elasticity of scale is k; the second one determines the conditions on the production function under which any input vector can be an optimum, for some choice of the price vector and the level of production.Elasticity of scale, homogeneous production functions, returns to scale, average costs, and marginal costs

Foreground removal requirements for measuring large-scale CMB B-modes in light of BICEP2

The most convincing confirmation that the B-mode polarization signal detected at degree scales by BICEP2 is due to the Cosmic Microwave Background (CMB) would be the measurement of its large-scale counterpart. We assess the requirements for diffuse component separation accuracy over large portions of the sky in order to measure the large-scale B-mode signal corresponding to a tensor to scalar ratio of r=0.1-0.2. We use the method proposed by Bonaldi & Ricciardi (2011) to forecast the performances of different simulated experiments taking into account noise and foreground removal issues. We do not consider instrumental systematics, and we implicitly assume that they are not the dominant source of error. If this is the case, the confirmation of an r=0.1-0.2 signal is achievable by Planck even for conservative assumptions regarding the accuracy of foreground cleaning. Our forecasts suggest that the combination of this experiment with BICEP2 will lead to an improvement of 25-45% in the constraint on r. A next-generation CMB polarization satellite, represented in this work by the COrE experiment, can reduce dramatically (by almost another order of magnitude) the uncertainty on r. In this case, however, the accuracy of foreground removal becomes critical to fully benefit from the increase in sensitivity.Comment: 8 pages, 3 figures, 1 table. Accepted by MNRA

Forecast B-modes detection at large scales in presence of noise and foregrounds

We investigate the detectability of the primordial CMB polarization B-mode power spectrum on large scales in the presence of instrumental noise and realistic foreground contamination. We have worked out a method to estimate the errors on component separation and to propagate them up to the power spectrum estimation. The performances of our method are illustrated by applying it to the instrumental specifications of the Planck satellite and to the proposed configuration for the next generation CMB polarization experiment COrE. We demonstrate that a proper component separation step is required in order achieve the detection of B-modes on large scales and that the final sensitivity to B-modes of a given experiment is determined by a delicate balance between noise level and residual foregrounds, which depend on the set of frequencies exploited in the CMB reconstruction, on the signal-to-noise of each frequency map, and on our ability to correctly model the spectral behavior of the foreground components. We have produced a flexible software tool that allows the comparison of performances on B-mode detection of different instrumental specifications (choice of frequencies, noise level at each frequency, etc.) as well as of different proposed approaches to component separation.Comment: 7 pages, 2 tables, 1 figure, accepted by MNRA

Representations and Identities for homogeneous Technologies

Using up to nine different ways to represent a homogeneous technology, this paper proves explicit one to one identities between most of those different representations of a technology, outlining the homogeneity properties of each representation. These identities, which allow to shift from one representation of a technology to another -and which are summarized in a matrix of identities - can be useful since they provide a tool to obtain explicit functional forms forhomogeneous technologies. They can also be useful to simplify computational procedures when different representations of a technology are needed. Finally, the document also refers explicitly to some aspects of producer theory that are often neglected or treated in a marginal way in the literature, such as the inverse supply, the non conditional cost and the inverse input demandfunctions.Identities, homogeneous production functions and firm theory

Sunyaev-Zel'dovich profiles and scaling relations: modelling effects and observational biases

We use high-resolution hydrodynamic re-simulations to investigate the properties of the thermal Sunyaev-Zel'dovich (SZ) effect from galaxy clusters. We compare results obtained using different physical models for the intracluster medium (ICM), and show how they modify the SZ emission in terms of cluster profiles and scaling relations. We also produce realistic mock observations to verify whether the results from hydrodynamic simulations can be confirmed. We find that SZ profiles depend marginally on the modelled physical processes, while they exhibit a strong dependence on cluster mass. The central and total SZ emission strongly correlate with the cluster X-ray luminosity and temperature. The logarithmic slopes of these scaling relations differ from the self-similar predictions by less than 0.2; the normalization of the relations is lower for simulations including radiative cooling. The observational test suggests that SZ cluster profiles are unlikely to be able to probe the ICM physics. The total SZ decrement appears to be an observable much more robust than the central intensity, and we suggest using the former to investigate scaling relations.Comment: 13 pages, 12 figures, accepted by MNRA