University of Oviedo

About: University of Oviedo is a education organization based out in Oviedo, Spain. It is known for research contribution in the topics: Population & Catalysis. The organization has 13423 authors who have published 31649 publications receiving 844799 citations. The organization is also known as: Universidá d'Uviéu & Universidad de Oviedo.

No, You Cannot Predict Elections with Twitter

Abstract: Predicting X from Twitter is a popular fad within the Twitter research subculture. It seems both appealing and relatively easy. Among such studies, electoral prediction is maybe the most attractive, and a growing body of literature exists on this topic. This research problem isn't only interesting, but is also extremely difficult. However, most authors seem to be more interested in claiming positive results than in providing sound and reproducible methods. It's also especially worrisome that recent papers seem to only acknowledge those studies supporting the idea that Twitter can predict elections. This is all problematic because while simple approaches are purported to be good enough, the predictive power of Twitter regarding elections has been greatly exaggerated, and difficult research problems still lie ahead.

Comparison of step length estimators from weareable accelerometer devices.

Abstract: Wearable accelerometry provides easily portable systems that supply real-time data adequate for gait analysis. When they do not provide direct measurement of a spatio- temporal parameter of interest, such as step length, it has to be estimated with a mathematical model from indirect sensor measurements. In this work we are concerned with the accelerometry-based estimation of the step length in straight line human walking. We compare five step length estimators. Measurements were taken from a group of four adult men, adding up a total of 800m per individual of walking data. Also modifications to these estimators are proposed, based on biomechanical considerations. Results show that this modifications lead to improvements of interest over previous methods. I. INTRODUCTION Gait analysis is frequently calculated by means of video- based recording of markers placed at end-points of all or a subset of body segments. However, this equipment is not easily portable, it requires off-line digitizing that can be time consuming and automated real-time systems which can be costly. This makes these systems impractical for use by the average clinician in daily practice. Other measurement de- vices such as force-plates, electro-goniometres or electrodes to measure EMG signals (1) are not designed for usability. Conversely, accelerometry provides easily portable sys- tems that supply real-time data. In addition, these systems come at a decreased cost when compared to video motion analysis systems, making them easily available to a wide range of clinics. Precision and repetibility characteristics of accelerometry make it adequate for gait analysis (2), and it has been widely used recently, mainly in ambulatory diagnostic (3), (4), (5), (6), (7). However, such systems do not provide direct measure of several spatio-temporal parameters of interest such as step length, walking distance or walking velocity. Instead, they have to be estimated with a mathematical model from indirect sensor measurements. Specifically, in this work we are concerned with the accelerometry-based estimation of the step length in straight line human walking. For instance, there exist empirical relations between the step length and the maximum and minimum vertical ac- celeration of the body's center of mass (COM) (8). More frequently it is accepted a linear relation of the step length with the step frequency (9). Finally, clinical studies show that

STAT4 associates with systemic lupus erythematosus through two independent effects that correlate with gene expression and act additively with IRF5 to increase risk

Abstract: Objectives: To confirm and define the genetic association of STAT4 and systemic lupus erythematosus, investigate the possibility of correlations with differential splicing and/or expression levels, and genetic interaction with IRF5. Methods: 30 tag SNPs were genotyped in an independent set of Spanish cases and controls. SNPs surviving correction for multiple tests were genotyped in 5 new sets of cases and controls for replication. STAT4 cDNA was analyzed by 59-RACE PCR and sequencing. Expression levels were measured by quantitative PCR. Results: In the fine-mapping, four SNPs were significant after correction for multiple testing, with rs3821236 and rs3024866 as the strongest signals, followed by the previously associated rs7574865, and by rs1467199. Association was replicated in all cohorts. After conditional regression analyses, two major independent signals represented by SNPs rs3821236 and rs7574865, remained significant across the sets. These SNPs belong to separate haplotype blocks. High levels of STAT4 expression correlated with SNPs rs3821236, rs3024866 (both in the same haplotype block) and rs7574865 but not with other SNPs. We also detected transcription of alternative tissue-specific exons 1, indicating presence of tissue-specific promoters of potential importance in the expression of STAT4 . No interaction with associated SNPs of IRF5 was observed using regression analysis. Conclusions: These data confirm STAT4 as a susceptibility gene for SLE and suggest the presence of at least two functional variants affecting levels of STAT4 . Our results also indicate that both genes STAT4 and IRF5 act additively to increase risk for SLE.

Boron nitride nanoresonators for phonon-enhanced molecular vibrational spectroscopy at the strong coupling limit

Abstract: Enhanced light-matter interactions are the basis of surface enhanced infrared absorption (SEIRA) spectroscopy, and conventionally rely on plasmonic materials and their capability to focus light to nanoscale spot sizes. Phonon polariton nanoresonators made of polar crystals could represent an interesting alternative, since they exhibit large quality factors, which go far beyond those of their plasmonic counterparts. The recent emergence of van der Waals crystals enables the fabrication of high-quality nanophotonic resonators based on phonon polaritons, as reported for the prototypical infrared-phononic material hexagonal boron nitride (h-BN). In this work we use, for the first time, phonon-polariton-resonant h-BN ribbons for SEIRA spectroscopy of small amounts of organic molecules in Fourier transform infrared spectroscopy. Strikingly, the interaction between phonon polaritons and molecular vibrations reaches experimentally the onset of the strong coupling regime, while numerical simulations predict that vibrational strong coupling can be fully achieved. Phonon polariton nanoresonators thus could become a viable platform for sensing, local control of chemical reactivity and infrared quantum cavity optics experiments.