Liberacion comercial y crecimiento economico en Mercosur 1994-2000

El presente trabajo es un estudio del desarrollo del Mercado Comun del Sur, desde sus antecedentes juridicos y su creacion en 1991 hasta la actualidad, señalando una fecha de referencia (1995), con objeto de analizar los efectos de la entrada en vigor del arancel externo comun en el crecimiento economico del Mercosur, contrastando el "shock" producido por la apertura de sus mercados al exterior, si bien la liberalizacion comercial venia siendo progresiva, de acuerdo al programa de desgravacion arancelaria. This paper studies the evolution of Mercosur, from its regulatory commences and its birth in 1991 to the present day. In order to analyse the effects of the implementation of a common external tariff in 1995 over the economic growth of Mercosur, we tested the shock caused for this policy measure. However, we should take into account that a policy addressed to achieve more international openness of these economies had been being progressively implemented before this date.

Magnetically-induced ferroelectricity in the (ND4)2[FeCl5(D2O)] molecular compound

The number of magnetoelectric multiferroic materials reported to date is scarce, as magnetic structures that break inversion symmetry and induce an improper ferroelectric polarization typically arise through subtle competition between different magnetic interactions. The (NH4)2[FeCl5(H2O)] compound is a rare case where such improper ferroelectricity has been observed in a molecular material. We have used single crystal and powder neutron diffraction to obtain detailed solutions for the crystal and magnetic structures of (NH4)2[FeCl5(H2O)], from which we determined the mechanism of multiferroicity. From the crystal structure analysis, we observed an order-disorder phase transition related to the ordering of the ammonium counterion. We have determined the magnetic structure below TN, at 2K and zero magnetic field, which corresponds to a cycloidal spin arrangement with magnetic moments contained in the ac-plane, propagating parallel to the c-axis. The observed ferroelectricity can be explained, from the obtained magnetic structure, via the inverse Dzyaloshinskii-Moriya mechanism

Low-optical-loss, low-resistance Ag/Ge based ohmic contacts to n-type InP for membrane based waveguide devices

We present the development of Ag/Ge based ohmic contacts to n-type InP with both low contact resistances and relatively low optical losses. A specific contact resistance as low as 1.5×10-6 O cm2 is achieved by optimizing the Ge layer thickness and annealing conditions. The use of Ge instead of metal as the first deposited layer results in a low optical absorption loss in the telecommunication wavelength range. Compared to Au based contacts, the Ag based metallization also shows considerably reduced spiking effects after annealing. Contacts with different lengths are deposited on top of InP membrane waveguides to characterize the optical loss before and after annealing. A factor of 5 reduction of the propagation loss compared to the conventional Au/Ge/Ni contact is demonstrated. This allows for much more optimized designs for membrane photonic devices

Investigation of EMIC wave scattering as the cause for the BARREL 17 January 2013 relativistic electron precipitation event: A quantitative comparison of simulation with observations

Abstract Electromagnetic ion cyclotron (EMIC) waves were observed at multiple observatory locations for several hours on 17 January 2013. During the wave activity period, a duskside relativistic electron precipitation (REP) event was observed by one of the Balloon Array for Radiation belt Relativistic Electron Losses (BARREL) balloons and was magnetically mapped close to Geostationary Operational Environmental Satellite (GOES) 13. We simulate the relativistic electron pitch angle diffusion caused by gyroresonant interactions with EMIC waves using wave and particle data measured by multiple instruments on board GOES 13 and the Van Allen Probes. We show that the count rate, the energy distribution, and the time variation of the simulated precipitation all agree very well with the balloon observations, suggesting that EMIC wave scattering was likely the cause for the precipitation event. The event reported here is the first balloon REP event with closely conjugate EMIC wave observations, and our study employs the most detailed quantitative analysis on the link of EMIC waves with observed REP to date. Key PointsQuantitative analysis of the first balloon REP with closely conjugate EMIC wavesOur simulation suggests EMIC waves to be a viable cause for the REP eventThe adopted model is proved to be applicable to simulating the REP event

X-ray Emission from the FU Orionis Star V1735 Cygni

The variable star V1735 Cyg (= Elias 1-12) lies in the IC 5146 dark cloud and is a member of the class of FU Orionis objects whose dramatic optical brightenings are thought to be linked to episodic accretion. We report the first X-ray detections of V1735 Cyg and a deeply-embedded class I protostar lying 24 arcsecs to its northeast. X-ray spectra obtained with EPIC on XMM-Newton reveal very high-temperature plasma (kT > 5 keV) in both objects, but no large flares. Such hard X-ray emission is not anticipated from accretion shocks and is a signature of magnetic processes. We place these new results into the context of what is presently known about the X-ray properties of FU Orionis stars and other accreting young stellar objects.Comment: 25 pages, 6 figure

Gravity Anomalies, Geodynamic Modelling and the Eastern Venezuela Basin Evolution.

This work examines the tectonic evolution of the Eastern Venezuela foreland basin by analysis of gravity anomalies and geodynamical modelling. Gravity data (8ºN-12ºN and 60ºW-66ºW) were processed to produce gravity anomaly maps, the most prominent feature being the minimum of -200 mGal isostatic, Bouguer and free-air anomalies associated with the basin. Positive gravity values characterize the northern terranes. Backstripping analysis of the sedimentary successions of four boreholes penetrating the Eastern Venezuela basin was applied to evaluate the history of subsidence. This demonstrated that an early passive margin phase (Cretaceous to early Oligocene) was followed by Oligocene to Recent tectonic subsidence of the foreland basin linked to the northern coastal compressional tectonic belt. Geohistorical analysis shows a major contribution to subsidence from early Oligocene, renewed during mid-Miocene times, in response to the loading of the South American plate on its northern margin. This tectonic loading pattern is younger from north to south. The observed gravity anomaly paired in eastern Venezuela is adequately reproduced by crustal models along profiles OO´ and II´ showing the isostatic negative anomaly over the foreland basin, primarily caused by the 10-13 km of sediments, the downwarping of dense lower crust and Moho down to 48 km depth. The positive gravity anomalies to the North are associated with southward thrusting of metamorphic and magmatic terranes, and dense Caribbean lithosphere. Dense subducting mantle may also be contributing to the northern positive anomaly belt as deep seismicity suggests. Two mechanisms were applied to explain the formation of the Eastern Venezuela foreland basin during a collisional regime. First, the “hidden load” approach explains the deflection but includes an intracrustal load whose magnitude is around a third of the supracrustal loads computed by an iterative process. This gives rise to a major misfit between the gravity anomaly computed for the structural model which takes into account all the geological and geophysical constraints when the contribution of the “hidden load” is included in the calculations. Second, since the hidden load hypothesis fails to explain the gravity profiles, a remaining viable explanation is release of compressional strain energy involving N-S crustal shortening involving faulting. I therefore explored a fault-based hypothesis which does not depend on hidden gravitational loads, but takes into account the clear relationship between the subsidence and the complementary uplift. In conclusion the prime cause of the evolution of the system depends on the forces on fault planes as they move, where the tractions on a thrust fault develop when a frictionless fault occurs in response to horizontal deviatoric compression of an elastic layer. As compression acts at the edges of the plate, the stresses are re-orientated producing the movement of the two plates along dipping fault planes (including the El Pilar fault). This led to the formation of the Eastern Venezuela foreland basin and linked uplift of the Eastern Serranía del Interior by spasmodic release of elastic strain energy

Laparoscopic nephrectomy for ex-vivo correction of renal artery aneurism and auto transplant

INTRODUCTION AND OBJECTIVES: Renal artery aneurism are a rare condition, with a prevalence of 0.09% of the population. The outcomes and clinical management of this patients depend on the presence of symptoms and subsequent risk of rupture. Most patients are managed by endovascular techniques, but difficult cases may present a challenge to urologists. METHODS: We present a case of a 35 year old female, history of high blood pressure with the diagnosis of a left renal artery aneurism with a diameter of 27 mm. The patient was evaluated by vascular surgery, was unsuitable for endovascular treatment and was submitted to a laparoscopic left nephrectomy with correction of the aneurism ex-vivo and the kidney was transplanted to the left iliac region. RESULTS: Operative time was 150 minutes and the warm ischemia time was 160 seconds. Blood loss was estimated in 80 mL with a hematocrit drop of 2% post operative. Drainage and vesical catheter were removed at day 2 and 6 post-operative, respectively. Post operative creatinine clearance was comparable to the pre operative (Post - 95 vs. Pre - 98 mL/min/1.73m2) The follow up is 15 months and the patients has a functioning kidney and had a normalization of the blood pressure. CONCLUSIONS: In experienced centers, laparoscopic nephrectomy with subsequent autotransplantion can be a safe and effective option in the management of specific conditions. This case presents a possible way to treat renal artery aneurisms that can’t be managed by endovascular procedures

Progress on agriculture in the UN climate talks: How COP21 can ensure a food-secure future

Agriculture, and consequently food security and livelihoods, is already being affected by climate change, according to latest science from the IPCC (Porter et al. 2014). The IPCC agrees that the world needs to produce at least 50% more food than we do today in order to meet the goal of feeding a projected 9 billion people by 2050. This must be achieved in the face of climatic variability and change, growing constraints on water and land for crops and livestock, and declining wild capture fishery stocks. Although the protection of food security lies within the core objective of the United Nations Framework Convention on Climate Change (UNFCCC) (Article 2), formal arrangements for addressing agriculture within COP21 are unlikely. CGIAR would welcome the strengthening of aspirations for food security through action on mitigation and adaptation within a new agreement. We recognise that the new climate agreement is unlikely to be prescriptive about how adaptation in agriculture is supported and how agriculture might contribute to emission cuts. These issues are addressed within countries’ INDCs and determined at national level

Hybrid Control Strategy for Force and Precise End Effector Positioning of a Twisted String Actuator

Funding Agency: Swiss Innovation Agency, InnosuissePeer reviewedPostprin

HISTORIA DE MÉXICO

GUÍA DIDÁCTICA / PLANEACIÓN DIDÁCTICA (NMS