939 research outputs found
"En euskera y en cristiano". Gènere, religió i nació al País Basc durant el franquisme [“En euskera y en cristiano”. Gender, religion and nation in the Basque Country during Francoism]
Des dels seus orígens, el vincle entre nacionalisme basc i religió catòlica ha estat prou estret. Aquest article pretén estudiar aquesta relació des d'una perspectiva de gènere durant la dictadura de Franco. Mitjançant la metodologia de la història oral, s'analitzaran els testimoniatges de quatre dones nascudes i/o residents al País Basc les dècades centrals del segle i que van militar en diferents grups catòlics. Amb el suport de fonts hemerogràfiques publicades per alguns d'aquests moviments, es tractaran també les diferències de discurs en l'àmbit urbà i rural. Així, es defensarà que els canvis experimentats pel catolicisme des de mitjan anys cinquanta van ser decisius en la transformació de la identitat religiosa i de gènere d'aquestes dones i que, al seu torn, els canvis en el model de feminitat hegemònic van provocar algunes tensions dins el discurs nacionalista.
[Since its inception, Basque nationalism has been closely linked with Catholicism. This paper aims to explore this connection from a gender perspective during Franco’s dictatorship by analysing the oral testimonies of four Catholic women who were born and/or were living in the Basque Country during the period 1940-70. It will also consider the differences in discourse in urban and rural environments by examining journals and newsletters published by distinct Catholic movements. Two hypotheses will be argued: first, that the changes experienced by Catholicism from the mid-1950s were decisive in the transformation of the religious and gender identity of these women; and second, that changes to the hegemonic femininity model generated tension in Basque nationalist discourse.
Biología en temas agropecuarios : una experiencia de formación docente a partir de la práctica
Effects of in-plane magnetic fields on the electronic cyclotron effective mass and Landé factor in GaAs-(Ga,Al)As quantum wells
The dependence of the electron Landé g-factor on carrier confinement in quantum wells recently gained both experimental and theoretical interest. The g factor of electrons in GaAs-(Ga,Al)As quantum wells is of special interest, as it changes its sign at a certain value of the well width. In the present work, the effects of an in-plane magnetic field on the cyclotron effective mass and on the Landé g^-factor in single GaAs-(Ga,Al)As quantum wells are studied. Theoretical calculations are performed in the framework of the effective-mass and non-parabolic-band approximations. The Ogg-McCombe Hamiltonian is used for the conduction-band electrons in the semiconductor heterostructure, and the Landé g^-factor theoretically evaluated is found in good agrement with available experimental measurements.858861Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
Effects Of Non-parabolicity And In-plane Magnetic Fields On The Cyclotron Effective Mass And G -factor In Gaas-(ga,al)as Quantum Wells
The envelope-function approach is used to theoretically study the effects of in-plane magnetic fields on the cyclotron effective mass and Landé g -factor associated to conduction electrons in single GaAs-(Ga,Al)As quantum wells. Non-parabolic and anisotropy effects are included in the calculations within the Ogg-McCombe effective Hamiltonian to describe the electron states in the semiconductor heterostructure. The electronic structure and both the cyclotron effective mass and Landé g -factor were obtained, by expanding the corresponding envelope wave functions in terms of harmonic-oscillator wave functions, as functions of the in-plane magnetic field, cyclotron orbit-center position, and quantum-well widths. This procedure allows us to consider the different terms in the Hamiltonian on equal footing, avoiding therefore the use of approximate methods to obtain the envelope wave functions and the corresponding energy spectrum. 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Self-similarity And Anti-self-similarity Of The Effective Landé G Factor In Gaas-(ga,al)as Fibonacci Superlattices Under In-plane Magnetic Fields
A theoretical study of the effects of in-plane magnetic fields on the Landé g factor associated to conduction electrons in GaAs-(Ga,Al)As Fibonacci superlattices is presented. We have used the Ogg-McCombe effective Hamiltonian, which includes nonparabolic and anisotropy effects, in order to describe the electron states in the Fibonacci heterostructure. We have expanded the corresponding electron envelope wave functions in terms of harmonic-oscillator wave functions, and obtained the Landé g factor for magnetic fields related by even powers of the golden mean τ=(1+5)2. Theoretical results for GaAs-(Ga,Al)As Fibonacci superlattices, under magnetic-field values scaled by τ2n, clearly exhibit a self-similar (for even n) or anti-self-similar (for odd n) behavior for the Landé g factors, as appropriate. © 2006 The American Physical Society.743Merlin, R., Bajema, K., Clarke, R., Juang, F.Y., Bhattacharya, P.K., (1985) Phys. Rev. Lett., 55, p. 1768. , PRLTAO 0031-9007 10.1103/PhysRevLett.55.1768Wang, Y.Y., Maan, J.C., (1989) Phys. Rev. B, 40, p. 1955. , PRBMDO 0163-1829 10.1103/PhysRevB.40.1955Toet, D., Potemski, M., Wang, Y.Y., Maan, J.C., Tapfer, L., Ploog, K., (1991) Phys. Rev. Lett., 66, p. 2128. , PRLTAO 0031-9007 10.1103/PhysRevLett.66.2128Maan, J.C., Chitta, V., Toet, D., Potemski, M., Ploog, K., (1992) Springer Series in Solid-State Sciences, 101, p. 549. , edited by G. Landwehr (Springer, BerlinBruno-Alfonso, A., Oliveira, L.E., De Dios-Leyva, M., (1995) Appl. Phys. Lett., 67, p. 536. , APPLAB 0003-6951 10.1063/1.115180Bruno-Alfonso, A., Reyes-Gómez, E., Oliveira, L.E., De Dios-Leyva, M., (1995) J. Appl. Phys., 78, p. 15. , JAPIAU. 0021-8979. 10.1063/1.360240De Dios-Leyva, M., Bruno-Alfonso, A., Reyes-Gómez, E., Oliveira, L.E., (1995) J. Phys.: Condens. Matter, 7, p. 9799. , JCOMEL. 0953-8984. 10.1088/0953-8984/7/50/014Nielsen, M.A., Chuang, I.L., (2000) Quantum Computation and Quantum Information, , Cambridge University Press, CambridgeSalis, G., Kato, Y.K., Ensslin, K., Driscol, D.C., Gossard, A.C., Awschalom, D.D., (2001) Nature (London), 414, p. 619. , NATUAS 0028-0836 10.1038/414619aZutic, I., Fabian, J., Das Sarma, S., (2004) Rev. Mod. Phys., 76, p. 323. , RMPHAT 0034-6861 10.1103/RevModPhys.76.323Engel, H.-A., Loss, D., (2005) Science, 309, p. 586. , SCIEAS 0036-8075 10.1126/science.1113203Hermann, C., Weisbuch, C., (1977) Phys. Rev. B, 15, p. 823. , PLRBAQ 0556-2805 10.1103/PhysRevB.15.823Le Jeune, P., Robart, D., Marie, X., Amand, T., Brosseau, M., Barrau, J., Kalevich, V., Rodichev, D., (1997) Semicond. Sci. Technol., 12, p. 380. , SSTEET 0268-1242 10.1088/0268-1242/12/4/006Malinowski, A., Harley, R.T., (2000) Phys. Rev. B, 62, p. 2051. , PRBMDO 0163-1829 10.1103/PhysRevB.62.2051Sapega, V.F., Ruf, T., Cardona, M., Ploog, K., Ivchenko, E.L., Mirlin, D.N., (1994) Phys. Rev. B, 50, p. 2510. , PRBMDO 0163-1829 10.1103/PhysRevB.50.2510Medeiros-Ribeiro, G., Pinheiro, M.V.B., Pimentel, V.L., Marega, E., (2002) Appl. Phys. Lett., 80, p. 4229. , APPLAB 0003-6951 10.1063/1.1483112Hanson, R., Witkamp, B., Vandersypen, L.M.K., Willems Van Beveren, L.H., Elzerman, J.M., Kouwenhoven, L.P., (2003) Phys. Rev. Lett., 91, p. 196802. , PRLTAO 0031-9007 10.1103/PhysRevLett.91.196802Rashba, E.I., Efros, A.L., (2003) Phys. Rev. Lett., 91, p. 126405. , PRLTAO 0031-9007 10.1103/PhysRevLett.91.126405De Sousa, R., Das Sarma, S., (2003) Phys. Rev. B, 68, p. 155330. , PRBMDO 0163-1829 10.1103/PhysRevB.68.155330Prado, S.J., Trallero-Giner, C., Alcalde, A.M., Lopez-Richard, V., Marques, G.E., (2004) Phys. Rev. B, 69, p. 201310. , PRBMDO 0163-1829 10.1103/PhysRevB.69.201310Destefani, C.F., Ulloa, S.E., (2005) Phys. Rev. B, 71, p. 161303. , PRBMDO 0163-1829 10.1103/PhysRevB.71.161303Ogg, N.R., (1966) Proc. Phys. Soc. London, 89, p. 431. , PPSOAU 0370-1328 10.1088/0370-1328/89/2/326McCombe, B.O., (1969) Phys. Rev., 181, p. 1206. , PHRVAO 0031-899X 10.1103/PhysRev.181.1206Braun, M., Rössler, U., (1985) J. Phys. C, 18, p. 3365. , JPSOAW. 0022-3719. 10.1088/0022-3719/18/17/013Golubev, V.G., Ivanov-Omskii, V.I., Minervin, I.G., Osutin, A.V., Polyakov, D.G., (1985) Sov. Phys. JETP, 61, p. 1214. , SPHJAR 0038-5646De Dios-Leyva, M., Reyes-Gómez, E., Perdomo-Leiva, C.A., Oliveira, L.E., (2006) Phys. Rev. B, 73, p. 085316. , PRBMDO. 0163-1829. 10.1103/PhysRevB.73.085316Li, E.H., (2000) Physica e (Amsterdam), 5, p. 215. , PELNFM 1386-9477 10.1016/S1386-9477(99)00262-3Dresselhaus, G., (1955) Phys. Rev., 100, p. 580. , PHRVAO 0031-899X 10.1103/PhysRev.100.58
Consumo, logo existo
A obra Antropologia & Consumo, organizada por três antropólogas que realizam trabalhos na área do consumo, resulta do simpósio Consumo e Construção de Sujeitos e Bens no Mundo Contemporâneo, realizado no Primeiro Congresso Latino-Americano de Antropologia, em Rosário, Argentina, em 2005. A seleção dos textos e os assuntos abordados apresentam o consumo sob vários aspectos, mostrando o quanto tema é abrangente e como permeia a vida dos sujeitos inseridos numa sociedade urbana contemporânea. Os..
2023 19th International Conference on the Design of Reliable Communication Networks (DRCN),
Producción CientíficaLink failures have a significant negative impact on the availability of a network and should therefore be resolved as soon as possible. Because of the slow convergence time of routing protocols upon detection of a link failure, several IP Fast ReRoute (FRR) mechanisms have been developed to overcome this problem. Recently, segment routing, which is a flexible and scalable way of doing source routing, enabled a new FRR mechanism called Topology Independent Loop-Free Alternate (TI-LFA). As the name suggests, the key feature of TI-LFA is that it guarantees a loop-free detour against any link failure in any network topology. However, typically fast responses to failures only aim to restore the loop-free connection between the affected routers and do not consider the resulting delay or impact on network congestion. This paper presents an initial study on the selected TI-LFA backup paths and their effect on the overall network performance. By means of simulation, we evaluate how efficient TI-LFA reroutes traffic for a number of traffic engineering approaches. Our results quantify the impact of different traffic engineering approaches and network loads on the performance of TI-LFA. This suggests potential directions for improving the effectiveness of TI-LFA protection in segment routing.EU H2020 MSCA ITN-ETN IoTalentum (grant no. 953442)EU H2020-ICT-52-2020 TeraFlow Project (grant 101015857)Ministerio de Ciencia e Innovación y Agencia Estatal de Investigación (Proyecto PID2020-112675RB-C42 financiado por MCIN/AEI/10.13039/501100011033
Assessment of Spatial Navigation and Docking Performance During Simulated Rover Tasks
INTRODUCTION: Following long-duration exploration transits, pressurized rovers will enhance surface mobility to explore multiple sites across Mars and other planetary bodies. Multiple rovers with docking capabilities are envisioned to expand the range of exploration. However, adaptive changes in sensorimotor and cognitive function may impair the crew s ability to safely navigate and perform docking tasks shortly after transition to the new gravitoinertial environment. The primary goal of this investigation is to quantify post-flight decrements in spatial navigation and docking performance during a rover simulation. METHODS: Eight crewmembers returning from the International Space Station will be tested on a motion simulator during four pre-flight and three post-flight sessions over the first 8 days following landing. The rover simulation consists of a serial presentation of discrete tasks to be completed within a scheduled 10 min block. The tasks are based on navigating around a Martian outpost spread over a 970 sq m terrain. Each task is subdivided into three components to be performed as quickly and accurately as possible: (1) Perspective taking: Subjects use a joystick to indicate direction of target after presentation of a map detailing current orientation and location of the rover with the task to be performed. (2) Navigation: Subjects drive the rover to the desired location while avoiding obstacles. (3) Docking: Fine positioning of the rover is required to dock with another object or align a camera view. Overall operator proficiency will be based on how many tasks the crewmember can complete during the 10 min time block. EXPECTED RESULTS: Functionally relevant testing early post-flight will develop evidence regarding the limitations to early surface operations and what countermeasures are needed. This approach can be easily adapted to a wide variety of simulated vehicle designs to provide sensorimotor assessments for other operational and civilian populations
Morphological and structural evidences concerning the origin of sheet fractures
[Abstract] Sheet fractures are well and widely developed in massive rocks, i.e., rocks lacking other partings, and they have been discussed in the literature for more than a century. Yet there is no agreement as to their origino Two contrasted
interpretations hold sway. Almost without exception, geologist adhere to the pressure release or erosional offloading hypothesis. Engineers and engineering
geologist, on the other hand, interpret sheet partings as buckling, i.e., crumpling
or bending out of plane, related to compressive stresses, particularly lateral
stresses.
After a review of nomenclature and a description of the characteristics of sheet fractures, a critique ofprevious explanations of their origin is presented. What are perceived to be critical Enes of structural and morphological evidence. bearing on the origin ofsheet fracture are next reviewed, and this is followed by a discusion of the possible origins of the structures
Intraspecific variation in juvenile tree growth under elevated CO2 alone and with O3: a meta-analysis
Atmospheric carbon dioxide (CO2) concentrations are expected to increase throughout this century, potentially fostering tree growth. A wealth of studies have examined the variation in CO2 responses across tree species, but the extent of intraspecific variation in response to elevated CO2 (eCO2) has, so far, been examined in individual studies and syntheses of published work are currently lacking. We conducted a meta-analysis on the effects of eCO2 on tree growth (height, stem biomass and stem volume) and photosynthesis across genotypes to examine whether there is genetic variation in growth responses to eCO2 and to understand their dependence on photosynthesis. We additionally examined the interaction between the responses to eCO2 and ozone (O3), another global change agent. Most of the published studies so far have been conducted in juveniles and in Populus spp., although the patterns observed were not species dependent. All but one study reported significant genetic variation in stem biomass, and the magnitude of intraspecific variation in response to eCO2 was similar in magnitude to previous analyses on interspecific variation. Growth at eCO2 was predictable from growth at ambient CO2 (R2 = 0.60), and relative rankings of genotype performance were preserved across CO2 levels, indicating no significant interaction between genotypic and environmental effects. The growth response to eCO2 was not correlated with the response of photosynthesis (P > 0.1), and while we observed 57.7% average increases in leaf photosynthesis, stem biomass and volume increased by 36 and 38.5%, respectively, and height only increased by 9.5%, suggesting a predominant role for carbon allocation in ultimately driving the response to eCO2. Finally, best-performing genotypes under eCO2 also responded better under eCO2 and elevated O3. Further research needs include widening the study of intraspecific variation beyond the genus Populus and examining the interaction between eCO2 and other environmental stressors. We conclude that significant potential to foster CO2-induced productivity gains through tree breeding exists, that these programs could be based upon best-performing genotypes under ambient conditions and that they would benefit from an increased understanding on the controls of allocation.We acknowledge the support from the Erasmus Mundus Master Course Mediterranean Forestry and Natural Resources Management (MEDfOR), Ramón y Cajal Fellowships (RYC-2012-10970
to V.R.d.D. and RYC-2008-02050 to J.P.F.), an Australian Research Council Discovery grant (DP130102576 to V.R.d.D.), an Australian Science Industry and Endowment Fund (RP04-
122 to D.T.T.) and the Spanish project FENOPIN (AGL2012-40151-C03-03 to J.V., J.P.F. and V.R.d.D.)
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