Non-Abelian Chern-Simons-Higgs vortices with a quartic potential

We have constructed numerically non-Abelian vortices in an SU(2) Chern-Simons-Higgs theory with a quartic Higgs potential. We have analyzed these solutions in detail by means of improved numerical codes and found some unexpected features we did not find when a sixth-order Higgs potential was used. The generic non-Abelian solutions have been generated by using their corresponding Abelian counterparts as initial guess. Typically, the energy of the non-Abelian solutions is lower than that of the corresponding Abelian one (except in certain regions of the parameter space). Regarding the angular momentum, the Abelian solutions possess the maximal value, although there exist non-Abelian solutions which reach that maximal value too. In order to classify the solutions it is useful to consider the non-Abelian solutions with asymptotically vanishing $A_t$ component of the gauge potential, which may be labelled by an integer number $m$. For vortex number $n=3$ and above, we have found uniqueness violation: two different non-Abelian solutions with all the global charges equal. Finally, we have investigated the limit of infinity Higgs self-coupling parameter and found a piecewise Regge-like relation between the energy and the angular momentum.Comment: 9 pages, 13 figure

Schwann cells and mesenchymal stem cells in laminin- or fibronectin-aligned matrices and regeneration across a critical size defect of 15 mm in the rat sciatic nerve

OBJECTIVE Artificial nerve guides are being developed to substitute for autograft repair after peripheral nerve injuries. However, the use of conduits is limited by the length of the gap that needs to be bridged, with the success of regeneration highly compromised in long gaps. Addition of aligned proregenerative cells and extracellular matrix (ECM) components inside the conduit can be a good strategy to achieve artificial grafts that recreate the natural environment offered by a nerve graft. The purpose of this study was to functionalize chitosan devices with different cell types to support regeneration in limiting gaps in the rat peripheral nerve. METHODS The authors used chitosan devices combined with proteins of the ECM and cells in a rat model of sciatic nerve injury. Combinations of fibronectin and laminin with mesenchymal stem cells (MSCs) or Schwann cells (SCs) were aligned within tethered collagen-based gels, which were placed inside chitosan tubes that were then used to repair a critical-size gap of 15 mm in the rat sciatic nerve. Electrophysiology and algesimetry tests were performed to analyze functional recovery during the 4 months after injury and repair. Histological analysis was performed at the midlevel and distal level of the tubes to assess the number of regenerated myelinated fibers. RESULTS Functional analysis demonstrated that SC-aligned scaffolds resulted in 100% regeneration success in a 15-mm nerve defect in this rat model. In contrast, animals that underwent repair with MSC-aligned constructs had only 90% regeneration success, and those implanted with acellular bridges had only 75% regeneration success. CONCLUSIONS These results indicate that the combination of chitosan conduits with ECM-enriched cellular gels represents a good alternative to the use of autografts for repairing long nerve gaps

Statistical analysis of soy cultivation in Argentina

Argentina are analyzed. The main objective is to obtain information that will be useful for the analysis of the environmental consequences of the progress of this crop in the country. This has been made by a descriptive statistical analysis and a factor analysis was used to identify factors which characterize the soybean crop and also a classification or clustering between provinces with similar characteristics. The information parameters studied were: the tendency and dispersion measures for soybean yield of 15 provinces in which it was grown between the 2001/02 and 2010/11 or from 2001/02 to 2010/11; the correlations between area harvested acreage, seeded area, production and performance, and the factors that bind some variables that characterize the soybean crop that allows a grouping between provinces with similar characteristics. Analyses were performed by using data obtained from: 1) MinAgri (last 10 seasons) b) 2001 National Census c) CNA 2002. From a group of variables: region extension (ha); population density 2001; population of the region in 2001; NBI 2001, literate people older than 10 years 2001; illiterate people older than 10 years 2001; permanent workers in the farming sector 2002; seeded area (ha) 2002; cultivated area of oily plants (ha) 2002; tractors 2002; harvesters 2002; seeded area (ha) 2001/02; harvested area (ha) 2001/02; production (Tn) 2001/02.Fil: Miranda del Fresno, Ma. Carolina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones y Estudios Ambientales; ArgentinaFil: Villacampa, Y.. Universidad de Alicante. Departamento de Qui­mica Orgánica; EspañaFil: Navarro Gonzalez, F. J.. Universidad de Alicante. Departamento de Qui­mica Orgánica; EspañaFil: Sastre Vazquez, P.. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Agronomia; Argentin

Mars Climate Database version 5

The Mars Climate Database (MCD) is a database of meteorological fields derived from General Circulation Model (GCM) numerical simulations [2,4] of the Martian atmosphere and validated using available observational data. The MCD includes complementary post-processing schemes such as high spatial resolution interpolation of environmental data and means of reconstructing the variability thereof. The GCM is developed at LMD (Laboratoire de Météorologie Dynamique, Paris, France) in collaboration with several teams in Europe: LATMOS (Laboratoire Atmosphères, Milieux, Observations Spatiales, Paris, France), the Open University (UK), the Oxford University (UK) and the Instituto de Astrofisica de Andalucia (Spain) with support from the European Space Agency (ESA) and the Centre National d'Etudes Spatiales (CNES). The MCD is freely distributed and intended to be useful and used in the framework of engineering applications as well as in the context of scientific studies which require accurate knowledge of the state of the Martian atmosphere. The Mars Climate Database (MCD) has over the years been distributed to more than 150 teams around the world. With the many improvements implemented in the GCM over the last few years, a new series of reference simulations have been run and compiled in a new version (version 5) of the Mars Climate Database, released in the first half of 2012

Assessing Gale Crater as an Exploration Zone for the First Human Mission to Mars

Mars is the "horizon goal" for human space flight [1]. Towards that endeavor, one must consider several factors in regards to choosing a landing site suitable for a human-rated mission including: entry, descent, and landing (EDL) characteristics, scientific diversity, and possible insitu resources [2]. Selecting any one place is a careful balance of reducing risks and increasing scientific return for the mission

Global Frequency and Geographical Distribution of Nighttime Streamer Corona Discharges (BLUEs) in Thunderclouds

Blue LUminous Events (BLUEs) are transient corona discharges occurring in thunderclouds and characterized by strong 337.0 nm light flashes with absent (or weak) 777.4 nm component. We present the first nighttime climatology of BLUEs as detected by the Modular Multispectral Imaging Array of the Atmosphere-Space Interaction Monitor showing their worldwide geographical and seasonal distribution. A total (land and ocean) of E~11 BLUEs occur around the globe every second at local midnight and the average BLUE land/sea ratio is E~7:4. The northwest region of Colombia shows an annual nighttime peak. Globally, BLUEs are maximized during the boreal summer-autumn, contrary to lightning which is maximed in the boreal summer. The geographical distribution of nighttime BLUEs shows three main regions in, by order of importance, the Americas, Europe/Africa and Asia/AustraliapublishedVersio

Neutrino Masses and Mixings from Supersymmetry with Bilinear R--Parity Violation: A Theory for Solar and Atmospheric Neutrino Oscillations

The simplest unified extension of the MSSM with bi-linear R--Parity violation naturally predicts a hierarchical neutrino mass spectrum, in which one neutrino acquires mass by mixing with neutralinos, while the other two get mass radiatively. We have performed a full one-loop calculation of the neutralino-neutrino mass matrix in the bi-linear \rp MSSM, taking special care to achieve a manifestly gauge invariant calculation. Moreover we have performed the renormalization of the heaviest neutrino, needed in order to get meaningful results. The atmospheric mass scale and maximal mixing angle arise from tree-level physics, while solar neutrino scale and oscillations follow from calculable one-loop corrections. If universal supergravity assumptions are made on the soft-supersymmetry breaking terms then the atmospheric scale is calculable as a function of a single \rp violating parameter by the renormalization group evolution due to the non-zero bottom quark Yukawa coupling. The solar neutrino problem must be accounted for by the small mixing angle (SMA) MSW solution. If these assumptions are relaxed then one can implement large mixing angle solutions, either MSW or just-so. The theory predicts the lightest supersymmetic particle (LSP) decay to be observable at high-energy colliders, despite the smallness of neutrino masses indicated by experiment. This provides an independent way to test this solution of the atmospheric and solar neutrino anomalies.Comment: 46 pages, references added + several misprints correcte

Testing neutrino mixing at future collider experiments

Low energy supersymmetry with bilinear breaking of R-parity leads to a weak-scale seesaw mechanism for the atmospheric neutrino scale and a radiative mechanism for the solar neutrino scale. The model has striking implications for collider searches of supersymmetric particles. Assuming that the lightest SUSY particle is the lightest neutralino we demonstrate that (i) The neutralino decays inside the detector even for tiny neutrino masses. (ii) Measurements of the neutrino mixing angles lead to predictions for the ratios of various neutralino branching ratios implying an independent test of neutrino physics at future colliders, such as the Large Hadron Collider or a Linear Collider.Comment: LaTex, 35 pages, 20 figures included, version 2, section on model shortened, Fig. 13 replaced, typos corrected, version to appear in Phys.Rev.