19,829 research outputs found
Fractal analysis of weld defect patterns obtained by radiographic tests
This paper presents a fractal analysis of radiographic patterns obtained from
specimens with three types of inserted welding defects: lack of fusion, lack of
penetration, and porosity. The study focused on patterns of carbon steel beads
from radiographs of the International Institute of Welding (IIW). The
radiographs were scanned using a greyscale with 256 levels, and the fractal
features of the surfaces constructed from the radiographic images were
characterized by means of Hurst, detrended-fluctuation, and minimal-cover
analyses. A Karhunen-Loeve transformation was then used to classify the curves
obtained from the fractal analyses of the various images, and a study of the
classification errors was performed. The obtained results indicate that fractal
analyses can be an effective additional tool for pattern recognition of weld
defects in radiographic tests.Comment: 7 pages, 2 figures. To appear AIP Conference Proceedings - QNDE 200
Differential mesenteric fat deposition in bovines fed on silage or concentrate is independent of glycerol membrane permeability
© The Animal Consortium 2011In the meat industry, the manipulation of fat deposition in cattle is of pivotal importance to improve production efficiency, carcass composition and ultimately meat quality. There is an increasing interest in the identification of key factors and molecular mechanisms responsible for the development of specific fat depots. This study aimed at elucidating the influence of breed and diet on adipose tissue membrane permeability and fluidity and their interplay on fat deposition in bovines. Two Portuguese autochthonous breeds, Alentejana and Barrosã, recognized as late- and early-maturing breeds, respectively, were chosen to examine the effects of breed and diet on fat deposition and on adipose membrane composition and permeability. Twenty-four male bovines from these breeds were fed on silage-based or concentrate-based diets for 11 months. Animals were slaughtered to determine their live slaughter and hot carcass weights, as well as weights of subcutaneous and visceral adipose depots. Mesenteric fat depots were excised and used to isolate adipocyte membrane vesicles where cholesterol content, fatty acid profile as well as permeability and fluidity were determined. Total accumulation of neither subcutaneous nor visceral fat was influenced by breed. In contrast, mesenteric and omental fat depots weights were higher in concentrate-fed bulls relative to silage-fed animals. Membrane fluidity and permeability to water and glycerol in mesenteric adipose tissue were found to be independent of breed and diet. Moreover, the deposition of cholesterol and unsaturated fatty acids, which may influence membrane properties, were unchanged among experimental groups. Adipose membrane lipids from the mesenteric fat depot of ruminants were rich in saturated fatty acids, and unaffected by polyunsaturated fatty acids dietary levels. Our results provide evidence against the involvement of cellular membrane permeability to glycerol on fat accumulation in mesenteric fat tissue of concentrate-fed bovines, which is consistent with the unchanged membrane lipid profile found among experimental groups.This study was supported by Fundação para a Ciência e a Tecnologia (FCT) through grant PTDC/CVT/2006/66114 and individual fellowships to Ana P. Martins (SFRH/BD/2009/65046), Ana S. H. Costa (SFRH/BD/2009/61068) and Susana V. Martins (SFRH/BPD/2009/63019). Paula A. Lopes is a researcher from the program ‘‘Ciência 2008’’ from FC
Relationship between top executive compensation and corporate governance: evidence from large Italian listed companies
The modernization of corporate governance aims the alignment of the interests of managers with those of companies, promoting a new discipline of internal controls and risk analysis with an enforcement of shareholder rights of information. This research investigates the impact of corporate governance variables –ownership, board of directors and remuneration committee– on executive compensation. A balanced sample of 52 Italian listed companies has been adopted to test the hypotheses, covering 55.98% and 47.13% of market capitalization in 2011 and 2015 respectively and including 669 board members. Theoretical models evidence a certain stability of compensation schemes for Italian managers over time. Findings suggest that there is a statistically significant positive effect of familiar ownership on the amount of compensation. Along with nature of ownership, the number of directors in the remuneration committee appointed by minorities assume a determinant role. With statistical significance, it affects negatively the compensation level, but, contrarily to best practices, it affects negatively the adoption of forms of incentive compensation.info:eu-repo/semantics/acceptedVersio
Nuno Portas and the Spanish influence on the definition of housing policies in Portugal in the period of democratic transition
Taking the housing crisis and the SAAL program as a central interest point of architects and
sociologists in the aftermath of the Portuguese revolution, this chapter tracks the influence of
Spanish architecture in Portugal and the relations of Portuguese and Spanish architects, signaling the
main role of Nuno Portas. It begins by introducing the background of the architecture exchange
between Portugal and Spain, since the 1960’s, through the diffusion and interchange activities of
Nuno Portas (section 2). It continues to discuss the role of architects on urban change during the
revolutionary process from the viewpoint Joan Antonio Solans experiences and writings (Section 3).
Then it takes on the social movements debate with Manuel Castells reflections and writings about
the new housing policies and experiences (Section 4). Finally, a short reflection on the interchange of
ideas and experiences between Portugal and Spain in presented in the conclusion (Section 5).info:eu-repo/semantics/submittedVersio
Entropy Function for Heterotic Black Holes
We use the entropy function formalism to study the effect of the Gauss-Bonnet
term on the entropy of spherically symmetric extremal black holes in heterotic
string theory in four dimensions. Surprisingly the resulting entropy and the
near horizon metric, gauge field strengths and the axion-dilaton field are
identical to those obtained by Cardoso et. al. for a supersymmetric version of
the theory that contains Weyl tensor squared term instead of the Gauss-Bonnet
term. We also study the effect of holomorphic anomaly on the entropy using our
formalism. Again the resulting attractor equations for the axion-dilaton field
and the black hole entropy agree with the corresponding equations for the
supersymmetric version of the theory. These results suggest that there might be
a simpler description of supergravity with curvature squared terms in which we
supersymmetrize the Gauss-Bonnet term instead of the Weyl tensor squared term.Comment: LaTeX file, 23 pages; v2: references added; v3: minor addition; v4:
minor change
Knowledge and attitude towards the gradual reduction of salt in bread – an online survey
Aim: Assess knowledge and attitude towards the gradual reduction of salt
in bread and the potential impact on eating habits of children (6-18 years)
and their families, as part as a Health Impact Assessment pilot study.N/
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