National University of La Plata

About: National University of La Plata is a education organization based out in La Plata, Argentina. It is known for research contribution in the topics: Population & Stars. The organization has 12993 authors who have published 30013 publications receiving 495118 citations. The organization is also known as: UNLP & Universidad Nacional de La Plata.

Dietary Variability in Cebus apella in Extreme Habitats: Evidence for Adaptability

Abstract: The dietary composition of Cebus apella in two subtropical forest environments of Argentina reflects the seasonal availability of potential food resources. In the marginal areas of the geographical distribution of this species, different resources are used during periods of scarcity. A greater tendency to use leaves in the diet is observed in the northwest (El Rey National Park), where there is greater seasonal variation of fruit availability. In El Rey, where there are few potential resources, the diet is dominated by a few resources, notably bromeliads. Where the resources are more abundant and the availability is more constant throughout the years (Baritu and Iguazu National Parks), the monkeys exhibit a feeding behavior similar to that seen in tropical areas. This ability of the genus Cebus to exploit resources not accessible to other primate species is one of the reasons for its wide geographical distribution and its widespread existence in ecosystems marginally used by primates.

Fractional antiferromagnetic skyrmion lattice induced by anisotropic couplings.

Abstract: Magnetic skyrmions are topological solitons with a nanoscale winding spin texture that hold promise for spintronics applications1-4. Skyrmions have so far been observed in a variety of magnets that exhibit nearly parallel alignment for neighbouring spins, but theoretically skyrmions with anti-parallel neighbouring spins are also possible. Such antiferromagnetic skyrmions may allow more flexible control than conventional ferromagnetic skyrmions5-10. Here, by combining neutron scattering measurements and Monte Carlo simulations, we show that a fractional antiferromagnetic skyrmion lattice is stabilized in MnSc2S4 through anisotropic couplings. The observed lattice is composed of three antiferromagnetically coupled sublattices, and each sublattice is a triangular skyrmion lattice that is fractionalized into two parts with an incipient meron (half-skyrmion) character11,12. Our work demonstrates that the theoretically proposed antiferromagnetic skyrmions can be stabilized in real materials and represents an important step towards their implementation in spintronic devices.

Degradation of magnesium and its alloys: dependence on the composition of the synthetic biological media.

Abstract: Magnesium and its alloys are highly degradable metals that are potentially useful as biomaterials, especially in orthopaedic and cardiovascular applications. However, the in vivo corrosion has proved to be too high. Because of the complexity of in vivo conditions, a careful study of the corrosion of magnesium in synthetic solutions that simulate the in vivo environment is necessary as a first approach to predict the actual in vivo situation. The aim of this work was to evaluate the influence of the electrolyte composition on the corrosion behavior of magnesium and two Mg-alloys in synthetic biological media. Pure magnesium and its alloys (AZ31 and LAE442) were employed in the experiments. Electrochemical potentiodynamic polarization curves were recorded in sodium chloride and PBS electrolytes with different chloride ion and albumin concentration. Optical and SEM observations complemented by EDX analysis were made. The results showed that magnesium corrosion is localized in chloride- and albumin-containing buffer solutions. They also showed that the chloride concentration and the presence of buffer and protein strongly affect the electrochemical behavior of magnesium and magnesium alloys.

Search for the direct production of charginos, neutralinos and staus in final states with at least two hadronically decaying taus and missing transverse momentum in pp collisions at √s = 8 TeV with the ATLAS detector

Abstract: Results of a search for the electroweak associated production of charginos and next-to-lightest neutralinos, pairs of charginos or pairs of tau sleptons are presented. These processes are characterised by final states with at least two hadronically decaying tau leptons, missing transverse momentum and low jet activity. The analysis is based on an integrated luminosity of 20.3 fb(-1) of proton-proton collisions at root s = 8 TeV recorded with the ATLAS experiment at the Large Hadron Collider. No significant excess is observed with respect to the predictions from Standard Model processes. Limits are set at 95% confidence level on the masses of the lighter chargino and next-to-lightest neutralino for various hypotheses for the lightest neutralino mass in simplified models. In the scenario of direct production of chargino pairs, with each chargino decaying into the lightest neutralino via an intermediate tau slepton, chargino masses up to 345 GeV are excluded for a massless lightest neutralino. For associated production of mass-degenerate charginos and next-to-lightest neutralinos, both decaying into the lightest neutralino via an intermediate tau slepton, masses up to 410 GeV are excluded for a massless lightest neutralino.