Desarrollo e implementación de un portal web de alimentos nutricionales www.cuidaloquecomes.com

Nuestro país, siendo un estado en vías de desarrollo, a logrado la disminución de casos de enfermedades transmisibles (difteria, sarampión, tétano, etc.); sin embargo los cambios en los hábitos alimenticios poco saludable (alta en grasa, azúcar y sal, baja en frutas, granos y vegetales) y la falta de actividad física han provocado un aumento rápido en las denominadas Enfermedades No Transmisibles (ENTs) en poblaciones cada vez más jóvenes. En el país las ENTs derivadas de los malos hábitos alimenticios son: diabetes mellitus, enfermedades cardiovasculares, hipertensión arterial, obesidad, tumores malignos e insuficiencia renal, estas molestias asolan a nuestro país desde hace dos décadas y actualmente se han convertido en las primeras causas de muerte y discapacidad. Ante esta premisa y aprovechando el impacto del Internet en la sociedad actual surge una fusión de ideas donde nace Cuidaloquecomes, un portal web especializado en alimentación saludable que provee servicio de catering a domicilio y tienda online de productos de primera necesidad, además de otros beneficios como: consultas con especialistas, foros e información actualizada. El objetivo principal del proyecto es, ayudar a personas con enfermedades no transmisibles a llevar un régimen de alimentación sana, contando con una asistencia segura, oportuna, higiénica y saludable para prevenir o tratar adecuadamente sus problemas de salud

IEEE 1355-Based Architecture for an ATM Switch: A Case for Onboard Switching and Processing

The recent evolution of the communication scenario has profound implications for the role of communication satellites within the communication infrastructure. Indeed, it raises the possibility that the satellite be viewed not merely as a repeater but rather as a network node in its own right in a hopefully integrated space/terrestrial network. We draw attention to the new IEEE 1355 Standard for Heterogeneous Inter-Connect as a possible platform to support several onboard processing functions, including onboard communications and onboard ATM switching. The IEEE 1355 is a new serial bus standard which enables high- performance, scalable, modular, parallel systems to be constructed with low system integration cost. This IEEE 1355- based approach can satisfy many of the requirements of onboard communications and onboard ATM switching, e.g., size, flexibility, reliability, fault-tolerance, and high communication processing speeds. This is made possible by using the highly integrated 1355 chipsets and performing protocol processing with multiple transputers in parallel. The IEEE 1355 approach also allows for easy expandability owing to its inherent design modularity

Strain control of a bandwidth-driven spin reorientation in Ca₃Ru₂O₇

The layered-ruthenate family of materials possess an intricate interplay of structural, electronic and magnetic degrees of freedom that yields a plethora of delicately balanced ground states. This is exemplified by Ca3Ru2O7, which hosts a coupled transition in which the lattice parameters jump, the Fermi surface partially gaps and the spins undergo a 90∘ in-plane reorientation. Here, we show how the transition is driven by a lattice strain that tunes the electronic bandwidth. We apply uniaxial stress to single crystals of Ca3Ru2O7, using neutron and resonant x-ray scattering to simultaneously probe the structural and magnetic responses. These measurements demonstrate that the transition can be driven by externally induced strain, stimulating the development of a theoretical model in which an internal strain is generated self-consistently to lower the electronic energy. We understand the strain to act by modifying tilts and rotations of the RuO6 octahedra, which directly influences the nearest-neighbour hopping. Our results offer a blueprint for uncovering the driving force behind coupled phase transitions, as well as a route to controlling them

Selective probing of magnetic order on Tb and Ir sites in stuffed Tb_2+xIr_2-xO_7-y using resonant X-ray scattering

We study the magnetic structure of the ``stuffed" (Tb-rich) pyrochlore iridate Tb$_{2+x}$Ir$_{2-x}$O$_{7-y}$, using resonant elastic x-ray scattering (REXS). In order to disentangle contributions from Tb and Ir magnetic sublattices, experiments were performed at the Ir $L_3$ and Tb $M_5$ edges, which provide selective sensitivity to Ir $5d$ and Tb $4f$ magnetic moments, respectively. At the Ir $L_3$ edge, we found the onset of long-range ${\bf k}={\bf 0}$ magnetic order below $T_{N}^\text{Ir}\sim$\,71\,K, consistent with the expected signal of all-in all-out (AIAO) magnetic order. Using a single-ion model to calculate REXS cross-sections, we estimate an ordered magnetic moment of $\mu_{5d}^{\text{Ir}} \approx 0.34(3)\,\mu_B$ at 5\,K. At the Tb $M_5$ edge, long-range ${\bf k}={\bf 0}$ magnetic order appeared below $\sim40\,$K, also consistent with an AIAO magnetic structure on the Tb site. Additional insight into the magnetism of the Tb sublattice is gleaned from measurements at the $M_5$ edge in applied magnetic fields up to 6\,T, which is found to completely suppress the Tb AIAO magnetic order. In zero applied field, the observed gradual onset of the Tb sublattice magnetisation with temperature suggests that it is induced by the magnetic order on the Ir site. The persistence of AIAO magnetic order, despite the greatly reduced ordering temperature and moment size compared to stoichiometric Tb$_{2}$Ir$_{2}$O$_{7}$, for which $T_{N}^{\text{Ir}} =130\,$K and $\mu_{5d}^{\text{Ir}}=0.56\,\mu_B$, indicates that stuffing could be a viable means of tuning the strength of electronic correlations, thereby potentially offering a new strategy to achieve topologically non-trivial band crossings in pyrochlore iridates

Manipulating the metal-to-insulator transition and magnetic properties in manganite thin films via epitaxial strain

Strain engineering of epitaxial transition metal oxide heterostructures offers an intriguing opportunity to control electronic structures by modifying the interplay between spin, charge, orbital, and lattice degrees of freedom. Here, we demonstrate that the electronic structure, magnetic and transport properties of La0.9Ba0.1MnO3 thin films can be effectively controlled by epitaxial strain. Spectroscopic studies and first-principles calculations reveal that the orbital occupancy in Mn eg orbitals can be switched from the d3z2-r2 orbital to the dx2-y2 orbital by varying the strain from compressive to tensile. The change of orbital occupancy associated with Mn 3d-O 2p hybridization leads to dramatic modulation of the magnetic and electronic properties of strained La0.9Ba0.1MnO3 thin films. Under moderate tensile strain, an emergent ferromagnetic insulating state with an enhanced ferromagnetic Curie temperature of 215 K is achieved. These findings not only deepen our understanding of electronic structures, magnetic and transport properties in the La0.9Ba0.1MnO3 system, but also demonstrate the use of epitaxial strain as an effective knob to tune the electronic structures and related physical properties for potential spintronic device applications

Coupling of magnetic order and charge transport in the candidate Dirac semimetal EuCd2As2

We use resonant elastic x-ray scattering to determine the evolution of magnetic order in EuCd2As2 below TN = 9.5 K, as a function of temperature and applied magnetic field. We find an A-type antiferromagnetic structure with in-plane magnetic moments, and observe dramatic magnetoresistive effects associated with field-induced changes in the magnetic structure and domain populations. Our ab initio electronic structure calculations indicate that the Dirac dispersion found in the nonmagnetic Dirac semimetal Cd3As2 is also present in EuCd2As2, but is gapped for T <TN due to the breaking of C3 symmetry by the magnetic structure

Probing electron-phonon interactions away from the Fermi level with resonant inelastic x-ray scattering

Interactions between electrons and lattice vibrations are responsible for a wide range of material properties and applications. Recently, there has been considerable interest in the development of resonant inelastic x-ray scattering (RIXS) as a tool for measuring electron-phonon ( e -ph) interactions. Here, we demonstrate the ability of RIXS to probe the interaction between phonons and specific electronic states both near to, and away from, the Fermi level. We perform carbon K -edge RIXS measurements on graphite, tuning the incident x-ray energy to separately probe the interactions of the π ∗ and σ ∗ electronic states. Our high-resolution data reveal detailed structure in the multiphonon RIXS features that directly encodes the momentum dependence of the e -ph interaction strength. We develop a Green’s-function method to model this structure, which naturally accounts for the phonon and interaction-strength dispersions, as well as the mixing of phonon momenta in the intermediate state. This model shows that the differences between the spectra can be fully explained by contrasting trends of the e -ph interaction through the Brillouin zone, being concentrated at the Γ and K points for the π ∗ states while being significant at all momenta for the σ ∗ states. Our results advance the interpretation of phonon excitations in RIXS and extend its applicability as a probe of e -ph interactions to a new range of out-of-equilibrium situations

Pressure tuning of bond-directional exchange interactions and magnetic frustration in the hyperhoneycomb iridate β−Li₂IrO₃

We explore the response of Ir 5 d orbitals to pressure in β − Li 2 IrO 3 , a hyperhoneycomb iridate in proximity to a Kitaev quantum spin-liquid (QSL) ground state. X-ray absorption spectroscopy reveals a reconstruction of the electronic ground state below 2 GPa, the same pressure range where x-ray magnetic circular dichroism shows an apparent collapse of magnetic order. The electronic reconstruction, which manifests a reduction in the effective spin-orbit interaction in 5 d orbitals, pushes β − Li 2 IrO 3 further away from the pure J eff = 1 / 2 limit. Although lattice symmetry is preserved across the electronic transition, x-ray diffraction shows a highly anisotropic compression of the hyperhoneycomb lattice which affects the balance of bond-directional Ir-Ir exchange interactions driven by spin-orbit coupling at Ir sites. An enhancement of symmetric anisotropic exchange over Kitaev and Heisenberg exchange interactions seen in theoretical calculations that use precisely this anisotropic Ir-Ir bond compression provides one possible route to the realization of a QSL state in this hyperhoneycomb iridate at high pressures