Interaction between a laser beam and semiconductor nanowires: application to the raman spectrum of Si nanowires

One presents in this work the study of the interaction between a focused laser beam and Si nanowires (NWs). The NWs heating induced by the laser beam is studied by solving the heat transfer equation by finite element methods (FEM). This analysis permits to establish the temperature distribution inside the NW when it is excited by the laser beam. The overheating is dependent on the dimensions of the NW, both the diameter and the length. When performing optical characterisation of NWs using focused laser beams, one has to consider the temperature increase introduced by the laser beam. An important issue concerns the fact that the NW's diameter has subwavelength dimensions, and is also smaller than the focused laser beam. The analysis of the thermal behaviour of the NWs under the excitation with the laser beam permits the interpretation of the Raman spectrum of Si NWs. It is demonstrated that the temperature increase induced by the laser beam plays a major role in shaping the Raman spectrum of Si NWs

Una revista de presente que mira al futuro

FARMACÉUTICOS COMUNITARIOS da un nuevo paso adelante. Desde su nacimiento en 2009 con su cabecera actual y como heredera de e-farmacéutico comunitario, la revista de ­SEFAC ha experimentado una continua progresión en busca de dos objetivos claros: por un lado, promover, fomentar y consolidar la investigación en farmacia comunitaria en España acercando también a los socios asuntos profesionales relevantes, y, por otro, convertirse en la revista científica de referencia en la publicación de artículos y trabajos de investigación realizados por farmacéuticos comunitarios o de interés para nuestro colectivo.FARMACÉUTICOS COMUNITARIOS da un nuevo paso adelante. Desde su nacimiento en 2009 con su cabecera actual y como heredera de e-farmacéutico comunitario, la revista de ­SEFAC ha experimentado una continua progresión en busca de dos objetivos claros: por un lado, promover, fomentar y consolidar la investigación en farmacia comunitaria en España acercando también a los socios asuntos profesionales relevantes, y, por otro, convertirse en la revista científica de referencia en la publicación de artículos y trabajos de investigación realizados por farmacéuticos comunitarios o de interés para nuestro colectivo

Interaction between a laser beam and semiconductor nanowires: application to the raman spectrum of Si nanowires

One presents in this work the study of the interaction between a focused laser beam and Si nanowires (NWs). The NWs heating induced by the laser beam is studied by solving the heat transfer equation by finite element methods (fem). This analysis permits to establish the temperature distribution inside the NW when it is excited by the laser beam. The overheating is dependent on the dimensions of the NW, both the diameter and the length. When performing optical characterization of the NWs using focused laser beams, one has to consider the temperature increase introduced by the laser beam. An important issue concerns the fact that the NWs diameter has subwavelength dimensions, and is also smaller than the focused laser beam. The analysis of the thermal behaviour of the NWs under the excitation with the laser beam permits the interpretation of the Raman spectra of Si NWs, where it is demonstrated that temperature induced by the laser beam play a major role in shaping the Raman spectrum of Si NW

Raman spectrum of group IV nanowires: influence of temperature

Group IV semiconductor nanowires are characterized by Raman spectroscopy. The results are analyzed in terms of the heating induced by the laser beam on the nanowires. By solving the heat transport equation one can simulate the temperature reached by the NWs under the exposure to a laser beam. The results are illustrated with Si and Si1-xGex nanowires. Both bundles of nanowires and individual nanowires are studied. The main experimental conditions contributing to the nanowire heating are discusse

LinkedIn “Big Four”: Job Performance Validation in the ICT Sector.

Social networks websites, and specially the LinkedIn platform, have changed the landscape of recruitment and personnel selection to a unified organizational process. Thus, apart from using LinkedIn as a recruitment tool, professionals also use it to make evaluative inferences regarding the individual characteristics of the candidates (e.g., their personality). However, most of the research focused on LinkedIn has left aside the evidence about its validity for decision making in the work setting. In our study we analyze the criterion oriented validity of LinkedIn incumbents professional profiles (N = 615) in the information and communication technology (ICT) sector with some measures of job performance. The results show four major factors underlying LinkedIn profiles about professional experience, social capital, updating knowledge, and non-profesional information. These factors are significantly related to productivity, absenteeism, and the potential for professional development. These findings are discussed in light of their theoretical and practical implications.post-print322 K

MicroRaman Spectroscopy of Si Nanowires: Influence of Size

Si Nanowires (NWs) were studied by Raman microspectroscopy. The Raman spectrum of the NWs reveals important thermal effects, which broaden and shift the one phonon Raman bands. The low thermal conductivity of the NWs and the low thermal dissipation are responsible for the temperature enhancement in the NW under the excitation with the laser beam. We have modeled, using finite element methods, the interaction between the laser beam and the NWs. The Raman spectrum of Si NWs is interpreted in terms of the temperature induced by the laser beam excitation, in correlation with finite element methods (fem) for studying the interaction between the laser beam and the NWs

Structural stability of SiGe nanoparticles under "in situ" electron beam irradiation in TEM

The structure of amorphous and crystalline SiGe nanoparticles, embedded in a dielectric medium, SiO2, and its stability under “in situ” electron beam irradiation is reported. High-resolution transmission electron microscopy and electron-diffraction pattern simulation by fast Fourier transform was used to analyze the crystal structure of the SiGe nanoparticles. Electron beam irradiation induces structural alternate order-disorder transitions in the nanoparticles for irradiation effects are mainly associated to the density of current. For irradiation with current densities < 7 A·cm-2 no effects are observed in the as-deposited amorphous samples, whereas in the crystallized samples, SiGe nanocrystals show higher stability and no effects are observed for irradiation densities of current < 50 A·cm-2. Irradiation with densities of current greater than these thresholds cause consecutive amorphous-crystalline or crystalline-amorphous structure transitions respectively for both amorphous and crystallized nanoparticles. A hexagonal structure is proposed for those nanocrystals obtained after irradiation in the as deposited amorphous samples

Big data methods, social media, and the psychology of entrepreneurial regions: capturing cross-county personality traits and their impact on entrepreneurship in the USA

There is increasing interest in the potential of artificial intelligence and Big Data (e.g., generated via social media) to help understand economic outcomes. But can artificial intelligence models based on publicly available Big Data identify geographical differences in entrepreneurial personality or culture? We use a machine learning model based on 1.5 billion tweets by 5.25 million users to estimate the Big Five personality traits and an entrepreneurial personality profile for 1,772 U.S. counties. The Twitter-based personality estimates show substantial relationships to county-level entrepreneurship activity, accounting for 20% (entrepreneurial personality profile) and 32% (Big Five traits) of the variance in local entrepreneurship, even when controlling for other factors that affect entrepreneurship. Whereas more research is clearly needed, our findings have initial implications for research and practice concerned with entrepreneurial regions and eco-systems, and regional economic outcomes interacting with local culture. The results suggest, for example, that social media datasets and artificial intelligence methods have the potential to deliver comparable information on the personality and culture of regions than studies based on millions of questionnaire-based personality tests

A hurdle strategy based on the combination of non-thermal treatments to control diarrheagenic E. coli in cheese

[EN] This study aimed to assess the efficacy of a multi-hurdle process combining mild High Hydrostatic Pressure (HHP) treatments and Thyme Oil (TO) edible films as a non-thermal method to combat pathogenic E. coli (aEPEC and STEC) in raw cow's-milk cheese stored at 7 ◦C and packaged under modified atmosphere. Changes in headspace atmosphere of cheese packs and treatment effects on Lactic Acid Bacteria (LAB) counts and diarrheagenic E. coli strains (aEPEC and STEC) were evaluated over a 28 d storage period. The results demonstrated that the combined treatment exhibited the most significant antimicrobial effect against both strains compared to individual treatments, achieving reductions of 4.30 and 4.80 log cfu/g after 28 d of storage for aEPEC and STEC, respectively. Notably, the synergistic effect of the combination treatment resulted in the complete inactivation of intact cells for STEC and nearly completed inactivation for aEPEC by the end of the storage period. These findings suggest that the combination of HHP with selected hurdles could effectively enhance microbial inactivation capacity, offering promising alternatives for improving cheese safety without affecting the starter microbiotaSIUniversidad de Leó