397 research outputs found
Portuguese language tensions and contradictions in diasporic contexts: Ethnographic and confessional narratives in greater Boston
Este artigo tem como objetivo analisar os emaranhados do “português” em contexto de diáspora e o seu reconhecimento como língua de herança. Através de uma pesquisa colaborativa na interseção disciplinar entre a antropologia, a sociolinguística e a educação, localizada em um pequeno território da área metropolitana de Boston, marcado por uma antiga imigração açoriana, a análise organiza-se em dois planos complementares: um local, socioespacial e comunitário, em narrativa etnográfica, e outro
individual, ancorado na trajetória linguística pessoal, em narrativa autobiográfica. A discussão enfatiza o papel da dimensão ideológica, transversal aos vários pontos analisados, abrindo para uma reflexão crítica sobre português como língua de herança nos EUA.
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This article aims to analyze the entanglements of “Portuguese” in a diasporic context and its recognition as a heritage language.Through a collaborative research at the disciplinary intersection between anthropology, sociolinguistics and education, located in a small territory in Greater Boston and marked by an older Azorean immigration, the analysis is organized on two complementary
levels: a local, socio-spatial and community, in an ethnographic narrative, and another one more individual, anchored in a personal-linguistic trajectory, in an autobiographical narrative. The discussion emphasizes the role of the ideological dimension, transversal to the various points analyzed, opening for a critical reflection on Portuguese as a heritage language in the United States.info:eu-repo/semantics/publishedVersio
Case report: Personalized transcatheter approach to mid-aortic syndrome by in vitro simulation on a 3-dimensional printed model
An 8-year-old girl, diagnosed with mid-aortic syndrome (MAS) at the age of 2 months and under antihypertensive therapy, presented with severe systemic hypertension (>200/120 mmHg). Computed tomography (CT) examination revealed aortic aneurysm between severe stenoses at pre- and infra-renal segments, and occlusion of principal splanchnic arteries with peripheral collateral revascularization. Based on CT imaging, preoperative three-dimensional (3D) anatomy was reconstructed to assess aortic dimensions and a dedicated in vitro planning platform was designed to investigate the feasibility of a stenting procedure under fluoroscopic guidance. The in vitro system was designed to incorporate a translucent flexible 3D-printed patient-specific model filled with saline. A covered 8-zig 45-mm-long Cheatham-Platinum (CP) stent and a bare 8-zig, 34-mm-long CP stent were implanted with partial overlap to treat the stenoses (global peak-to-peak pressure gradient > 60 mmHg), excluding the aneurysm and avoiding risk of renal arteries occlusion. Percutaneous procedure was successfully performed with no residual pressure gradient and exactly replicating the strategy tested in vitro. Also, as investigated on the 3D-printed model, additional angioplasty was feasible across the frames of the stent to improve bilateral renal flow. Postoperative systemic pressure significantly reduced (130/70 mmHg) as well as dosage of antihypertensive therapy. This is the first report demonstrating the use of a 3D-printed model to effectively plan percutaneous intervention in a complex pediatric MAS case: taking full advantage of the combined use of a patient-specific 3D model and a dedicated in vitro platform, feasibility of the stenting procedure was successfully tested during pre-procedural assessment. Hence, use of patient-specific 3D-printed models and in vitro dedicated platforms is encouraged to assist pre-procedural planning and personalize treatment, thus enhancing intervention success
Vulnerability analysis of satellite-based synchronized smart grids monitoring systems
The large-scale deployment of wide-area monitoring systems could play a strategic role in supporting the evolution of traditional power systems toward smarter and self-healing grids. The correct operation of these synchronized monitoring systems requires a common and accurate timing reference usually provided by a satellite-based global positioning system. Although these satellites signals provide timing accuracy that easily exceeds the needs of the power industry, they are extremely vulnerable to radio frequency interference. Consequently, a comprehensive analysis aimed at identifying their potential vulnerabilities is of paramount importance for correct and safe wide-area monitoring system operation. Armed with such a vision, this article presents and discusses the results of an experimental analysis aimed at characterizing the vulnerability of global positioning system based wide-area monitoring systems to external interferences. The article outlines the potential strategies that could be adopted to protect global positioning system receivers from external cyber-attacks and proposes decentralized defense strategies based on self-organizing sensor networks aimed at assuring correct time synchronization in the presence of external attacks
PAMELA's measurements of geomagnetic cutoff variations during solar energetic particle events
Data from the PAMELA satellite experiment were used to measure the
geomagnetic cutoff for high-energy ( 80 MeV) protons during the solar
particle events on 2006 December 13 and 14. The variations of the cutoff
latitude as a function of rigidity were studied on relatively short timescales,
corresponding to single spacecraft orbits (about 94 minutes). Estimated cutoff
values were cross-checked with those obtained by means of a trajectory tracing
approach based on dynamical empirical modeling of the Earth's magnetosphere. We
find significant variations in the cutoff latitude, with a maximum suppression
of about 6 deg for 80 MeV protons during the main phase of the storm. The
observed reduction in the geomagnetic shielding and its temporal evolution were
compared with the changes in the magnetosphere configuration, investigating the
role of IMF, solar wind and geomagnetic (Kp, Dst and Sym-H indexes) variables
and their correlation with PAMELA cutoff results.Comment: Conference: The 34th International Cosmic Ray Conference (ICRC2015),
30 July - 6 August, 2015, The Hague, The Netherlands, Volume:
PoS(ICRC2015)28
Time dependence of the proton flux measured by PAMELA during the July 2006 - December 2009 solar minimum
The energy spectra of galactic cosmic rays carry fundamental information
regarding their origin and propagation. These spectra, when measured near
Earth, are significantly affected by the solar magnetic field. A comprehensive
description of the cosmic radiation must therefore include the transport and
modulation of cosmic rays inside the heliosphere. During the end of the last
decade the Sun underwent a peculiarly long quiet phase well suited to study
modulation processes. In this paper we present proton spectra measured from
July 2006 to December 2009 by PAMELA. The large collected statistics of protons
allowed the time variation to be followed on a nearly monthly basis down to 400
MV. Data are compared with a state-of-the-art three-dimensional model of solar
modulation.Comment: 17 pages, 5 figures, 1 table, to appear in Astrophysical Journal.
Corrected two elements of Table
Time dependence of the e^- flux measured by PAMELA during the July 2006 - December 2009 solar minimum
Precision measurements of the electron component in the cosmic radiation
provide important information about the origin and propagation of cosmic rays
in the Galaxy not accessible from the study of the cosmic-ray nuclear
components due to their differing diffusion and energy-loss processes. However,
when measured near Earth, the effects of propagation and modulation of galactic
cosmic rays in the heliosphere, particularly significant for energies up to at
least 30 GeV, must be properly taken into account. In this paper the electron
(e^-) spectra measured by PAMELA down to 70 MeV from July 2006 to December 2009
over six-months time intervals are presented. Fluxes are compared with a
state-of-the-art three-dimensional model of solar modulation that reproduces
the observations remarkably well.Comment: 40 pages, 18 figures, 1 tabl
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