Anisotropic thermal magnetoresistance for an active control of radiative heat transfer

We predict a huge anisotropic thermal magnetoresistance (ATMR) in the near-field radiative heat transfer between magneto-optical particles when the direction of an external magnetic field is changed with respect to the heat current direction. We illustrate this effect with the case of two InSb spherical particles where we find that the ATMR amplitude can reach values of up to 800% for a magnetic field of 5 T, which is many orders of magnitude larger than its spintronic analogue in electronic devices. This thermomagnetic effect could find broad applications in the fields of ultrafast thermal management as well as magnetic and thermal remote sensing.Comment: 6 pages, 4 figure

Calculations of the Temperature and Alloy Composition Effects on the Optical Properties of Alx Ga1-x Asy Sb1-y and Gax In1-x Asy Sb1-y in the Spectral Range 0.5-6 eV

A detailed analysis is presented on the temperature and alloy composition dependence of the optical properties of III-V alloys Alx Ga1-x Asy Sb1-y and Gax In1-x Asy Sb1-y in the energy range 0.5-6 eV. Expressions for the complex dielectric function are based on a semiempirical phenomenological model, which takes under consideration indirect and direct transitions below and above the fundamental absorption edge. Dielectric function and absorption coefficient calculations are in satisfactory agreement with available experimental data. Other dielectric related optical data, such as the refractive index, extinction, and reflection coefficients, can also be obtained from the model. © 2007 American Institute of Physics. (DOI: 10.1063/1.2751406

Design of a case management model for people with chronic disease (Heart Failure and COPD). Phase I: modeling and identification of the main components of the intervention through their actors: patients and professionals (DELTA-ICE-PRO Study

Background Chronic diseases account for nearly 60% of deaths around the world. The extent of this silent epidemic has not met determined responses in governments, policies or professionals in order to transform old Health Care Systems, configured for acute diseases. There is a large list of research about alternative models for people with chronic conditions, many of them with an advanced practice nurse as a key provider, as case management. But some methodological concerns raise, above all, the design of the intervention (intensity, frequency, components, etc). Methods/Design Objectives: General: To develop the first and second phases (theorization and modeling) for designing a multifaceted case-management intervention in people with chronic conditions (COPD and heart failure) and their caregivers. Specific aims: 1) To identify key events in people living with chronic disease and their relation with the Health Care System, from their point of view. 2) To know the coping mechanisms developed by patients and their caregivers along the story with the disease. 3) To know the information processing and its utilization in their interactions with health care providers. 4) To detect potential unmet needs and the ways deployed by patients and their caregivers to resolve them. 5) To obtain a description from patients and caregivers, about their itineraries along the Health Care System, in terms of continuity, accessibility and comprehensiveness of care. 6) To build up a list of promising case-management interventions in patients with Heart Failure and COPD with this information in order to frame it into theoretical models for its reproducibility and conceptualization. 7) To undergo this list to expert judgment to assess its feasibility and pertinence in the Andalusian Health Care. Design: Qualitative research with two phases: For the first five objectives, a qualitative technique with biographic stories will be developed and, for the remaining objectives, an expert consensus through Delphi technique, on the possible interventions yielded from the first phase. The study will be developed in the provinces of Almería, Málaga and Granada in the Southern Spain, from patients included in the Andalusian Health Care Service database with the diagnosis of COPD or Heart Failure, with the collaboration of case manager nurses and general practitioners for the assessment of their suitability to inclusion criteria. Patients and caregivers will be interviewed in their homes or their Health Centers, with their family or their case manager nurse as mediator. Discussion First of a series of studies intended to design a case-management service for people with heart failure and COPD, in the Andalusian Health Care System, where case management has been implemented since 2002. Accordingly with the steps of a theoretical model for complex interventions, in this study, theorization and intervention modeling phases will be developed.This research was carried out with the support of one research grant, awarded by the Regional Health Ministry of Andalusia (Exp. 0222/2008

On the Specific Adsorption of 7-methylguanine on Au(111) Surfaces for the Electroanalytical Sensing of Methylation Levels

The electrochemical determination of 7-methylguanine (7-mG) may result of interest because its presence can serve as probe of cytosine methylation of which is known as the most relevant epigenetic modification of DNA. This work explores the electrochemical response of 7-mG on different gold surfaces, both poly and single crystalline surfaces (Au (110), Au (111) and Au (100)). The results show that the adsorption-desorption process of the 7-mG is sensitive to the surface structure of the gold electrodes. Particularly, 7-mG adsorption-desorption profile on a Au (111) electrode exhibits some specific contributions which are found sensitive to the 7-mG concentration and, thereby could allow its quantification. These results may shed light on the future development of an electrochemical sensor for the diagnosis of the methylation degree in DNA.Authors would like to acknowledge funding obtained through the Spanish Ministry of Science and Innovation (MICINN) CTQ2013-48280-C3-3-R project

A Molecular Platinum Cluster Junction: A Single-Molecule Switch

We present a theoretical study of the electronic transport through single-molecule junctions incorporating a Pt6 metal cluster bound within an organic framework. We show that the insertion of this molecule between a pair of electrodes leads to a fully atomically engineered nano-metallic device with high conductance at the Fermi level and two sequential high on/off switching states. The origin of this property can be traced back to the existence of a HOMO which consists of two degenerate and asymmetric orbitals, lying close in energy to the Fermi level of the metallic leads. Their degeneracy is broken when the molecule is contacted to the leads, giving rise to two resonances which become pinned close to the Fermi level and display destructive interference.Comment: 4 pages, 4 figures. Reprinted (adapted) with permission from J. Am. Chem. Soc., 2013, 135 (6), 2052. Copyright 2013 American Chemical Societ

Caracterización y evaluación de competencias TICs

La formación por competencias ocupa un espacio relevante en las discusiones referidas a temas de calificación profesional. Dentro de este proceso, un elemento particularmente importante es el de la evaluación de las competencias y, por ende, la certificación de las mismas. El presente trabajo trata sobre el marco general de abordaje de la problemática de la evaluación de competencias, y particularmente esta problemática asociada a un tipo de competencias individuales específicas, las competencias en ámbito TIC’s (Tecnologías de Información y Comunicaciones). Se exponen los lineamientos generales y principios conceptuales sobre los que se basa un trabajo de investigación que los autores llevan a cabo en Universidad Tecnológica Nacional - Facultad Regional Córdoba.Eje: Tecnología Informática Aplicada en EducaciónRed de Universidades con Carreras en Informática (RedUNCI

Caracterización y evaluación de competencias TICs

La formación por competencias ocupa un espacio relevante en las discusiones referidas a temas de calificación profesional. Dentro de este proceso, un elemento particularmente importante es el de la evaluación de las competencias y, por ende, la certificación de las mismas. El presente trabajo trata sobre el marco general de abordaje de la problemática de la evaluación de competencias, y particularmente esta problemática asociada a un tipo de competencias individuales específicas, las competencias en ámbito TIC’s (Tecnologías de Información y Comunicaciones). Se exponen los lineamientos generales y principios conceptuales sobre los que se basa un trabajo de investigación que los autores llevan a cabo en Universidad Tecnológica Nacional - Facultad Regional Córdoba.Eje: Tecnología Informática Aplicada en EducaciónRed de Universidades con Carreras en Informática (RedUNCI

Inhibitory effect against polymerase and ribonuclease activities of HIV-reverse transcriptase of the aqueous leaf extract of Terminalia triflora

Dichloromethane, methanol and aqueous extracts from the leaves of Terminalia triflora were investigated for their inhibitory effect on polymerase and ribonuclease activities of HIV reverse transcriptase.The most potent activity was found in the aqueous extract, which inhibited both polymerase and ribonuclease activities of the enzyme with an IC50 of 1.6 micro g/mL and 1.8 micro g/mL respectively. The antiinfective activity of the extract was demonstrated in HLT4LacZ-IIIB cell culture with an IC50 of 1.0 micro g/mL. The extract was submitted to a purification process by extractive and chromatographic methods. The activity remained in the hydrophillic fraction. Tannins present in this active purified fraction, as determined by TLC and HPLC methods, could account for the anti HIV-RT activity found in the aqueous extract