Document Retrieval on Repetitive Collections

Document retrieval aims at finding the most important documents where a pattern appears in a collection of strings. Traditional pattern-matching techniques yield brute-force document retrieval solutions, which has motivated the research on tailored indexes that offer near-optimal performance. However, an experimental study establishing which alternatives are actually better than brute force, and which perform best depending on the collection characteristics, has not been carried out. In this paper we address this shortcoming by exploring the relationship between the nature of the underlying collection and the performance of current methods. Via extensive experiments we show that established solutions are often beaten in practice by brute-force alternatives. We also design new methods that offer superior time/space trade-offs, particularly on repetitive collections.Comment: Accepted to ESA 2014. Implementation and experiments at http://www.cs.helsinki.fi/group/suds/rlcsa

Light charged Higgs boson production at the Large Hadron electron Collider

We study the production of a light charged Higgs boson at the future Large Hadron electron Collider (LHeC), through the process $e^- p \to \nu_e H^- q$ considering both decay channels $H^- \to b \bar c$ and $H^- \to \tau \bar \nu_\tau$ in the final state. We analyse these processes in the context of the 2-Higgs Doublet Model Type III (2HDM-III) and assess the LHeC sensitivity to such $H^-$ signals against a variety of both reducible and irreducible backgrounds. We confirm that prospects for $H^-$ detection in the 2HDM-III are excellent assuming standard collider energy and luminosity conditions.Comment: 12 pages, 12 figures. Accepted in Physical Review

Study of the effects of magnetic braking on the lithium abundances of the Sun and solar-type stars

The study of lithium (Li) surface abundance in the Sun and young stellar globular clusters which are seemingly anomalous in present-day scenarios, as well as the influence of rotation and magnetic braking (MB) on its depletion during pre-main sequence (PMS) and main sequence (MS). In this work, the effects of rotational mixing and of the rotational hydrostatic effects on Li abundances are studied by simulating several grids of PMS and MS rotating and non-rotating models. Those effects are combined with the additional impact of the MB (with magnetic field intensities ranging between 3.0 and 5.0 G). The data obtained from simulations are confronted by comparing different stellar parameters. The results show that the surface Li abundance for the Sun like models at the end of the PMS and throughout the MS decreases when rotational effects are included, i.e. the Li depletion rate for rotating models is higher than for non-rotating ones. This effect is attenuated when the MB produced by a magnetic field is present. This physical phenomena impacts also the star effective temperature ($T_{\mathrm{eff}}$) and its location in the HR diagram. The impact of MB in Li depletion is sensitive to the magnetic field intensity: the higher it is, the lower the Li destruction. A direct link between the magnetic fields and the convective zone (CZ) size is observed: stronger magnetic fields produce shallower CZ's. This result suggests that MB effect must be taken into consideration during PMS if we aim to reproduce Li abundances in young clusters

Star formation history in the solar neighborhood: the link between stars and cosmology

Using a cosmological galactic evolutionary approach to model the Milky Way, we calculate the star formation history (SFH) of the solar neighborhood. The good agreement we obtain with the observational inferences suggests that our physical model describes accurately the long term/large spatial trends of the local and global Milky Way SFH. In this model, star formation is triggered by disk gravitational instabilities and self-regulated by an energy balance in the ISM. The drivers of the SFH are the cosmological gas infall rate and the gas surface density determined by the primordial spin parameter. A LambdaCDM cosmology was used throughout.Comment: 8 pages, uses kluwer.cls. Invited talk, to appear in "New Quests in Stellar Astrophysics: The link between Stars and Cosmology", eds. M. Chavez, A. Bressan, A. Buzzoni & D. Mayya, Kluwer Academic Publisher

Nivel de información médica sobre diabetes, actitud de los pacientes hacia la enfermedad y su asociación con el nivel de control glucémico

ObjetivoDeterminar el nivel de información y de actitud que sobre su enfermedad tienen pacientes con diabetes tipo 2 (DM2) y su asociación con el nivel de control glucémico.DiseñoEncuesta transversal survey.EmplazamientoDos unidades de medicina familiar.PacientesDoscientos sujetos con DM2.IntervencionesSe aplicaron 2 instrumentos validados para valorar nivel de conocimientos y actitud, y se midió el promedio de las últimas 6 glucemias.Mediciones y resultadosLa calificación global del instrumento de conocimientos fue 58,6 ± 17,9 (escala 0-100). Para el instrumento de actitud fue de 18,9 ± 2,1 (escala 0-35). La calificación de conocimientos del grupo controlado fue de 55,48 ± 16,8, y la del grupo descontrolado de 59,2 ± 18,1. La calificación sobre actitud del grupo controlado fue de 17,8 ± 2,3, y la del grupo descontrolado de 19,1 ± 2 (p = 0,001). El nivel de información proporcionado por el médico familiar fue del 42,9%, por el equipo de salud del 10,2% y por otras fuentes del 6,3%. En cuanto al análisis del grado de actitud y el nivel de información, hubo una mejor actitud cuando la información fue proporcionada por otras fuentes (p < 0,05). Por lo que respecta al porcentaje de información y el control glucémico, el nivel de control fue mejor cuando la información fue proporcionada por el equipo de salud (p < 0,01).ConclusionesEl nivel de información médica sobre diabetes proporcionada por el médico familiar y el equipo de salud es bajo, y sólo en este último caso se asocia a un mejor control glucémico. La actitud es mejor cuando se recibe información sobre diabetes de otras fuentes.ObjectiveTo determine the level of information and attitude that it has more than enough their illness has patient with diabetes type 2 (DM2), and their association with level of glucemic control.DesignCross-sectional.SettingTwo units of family medicine.Patient200 subject with DM2.InterventionsTwo instruments were applied validated to measure, level of knowledge and attitude was measured the average of the last 6 glucaemias.Measurements and resultsThe qualification average of the instrument of knowledge was 58.6 ± 17.9 (it scale 0–100). For the instrument of attitude it was of 18.9 ± 2.1 (it scale 0 at 35). The qualification of knowledge of the controlled group was of 55.48 ± 16.8, and of the uncontrolled group it was of 59.2 ± 18.1. The qualification has more than enough attitude of the controlled group it was of 17.8 ± 2.3, and of the uncontrolled group of 19.1 ± 2, p = 0.001. The proportionate level of information the family doctor was of 42.9%, of the team of health of 10.2% and of other sources of 6.3%. At the analysis of the degree of attitude and the level of information, there was a better attitude when the information was provided by other sources p < 0.05. In the percentage of information and the level of glucemic control, the control level was better when the information was for the team of health p < 0.01.ConclusionsThe level of medical information on diabetes provided by the family doctor and the team of health is low and it doesn't and only this last are associate to better glucemic control. The attitude is better when one receives information of other sources

Utilidad diagnóstica de los marcadores de estrés oxidativo en artritis reumatoide precoz en pacientes no fumadores y anti-CCP negativos

Fundamento. A pesar del desarrollo de nuevos marcadores y cri- terios diagnósticos para la artritis reumatoide (AR), todavía mu- chos pacientes son diagnosticados tras varios años de síntomas. Los marcadores de estrés oxidativo se incrementan ya en una fase temprana de la enfermedad. El objetivo del presente estudio fue evaluar el valor diagnóstico adicional de estos marcadores. Método. Se realizó un estudio de casos y controles. Los pacien- tes reclutados para el estudio cumplían los criterios para AR de la ACR 1987, todos ellos tenían menos de 2 años de síntomas y sin tratamiento previo con fármacos modificadores de la enfer- medad antirreumática (DMARD), esteroides o vitamina E. Los controles fueron seleccionados de los familiares del paciente y pareados (1:1) por sexo, edad, hábito tabáquico actual. Los marcadores de daño oxidativo que se midieron fueron malo- nildialdehído (MDA), hidroperóxidos lipídicos (LOOH) y pro- teínas carboniladas (CP). El Análisis estadístico se realizó de acuerdo con la STARD. resultados. Se incluyeron sesenta y cinco pacientes con AR sin tratamiento y 65 controles sanos. LOOH, CP, los anticuerpos con péctidos citrulinados (anti-CCP) y el factor reumatoide (FR) fueron significativamente mayores en los pacientes, y MDA fue mayor en los controles. Los mismos resultados se obtuvieron en los subgrupos de pacientes que fuman o no, y en anti-CCP positivos o negativos. El valor diagnóstico de los marcadores tradicionales mostró una buena especificidad pero una baja sensibilidad. La construcción de los modelos logísti- cos con la adicción de LOOH y CP aumenta la sensibilidad y el área bajo la curva ROC, especialmente en los no fumadores (66%) y los pacientes negativos ante-CCP (51%). conclusiones. Al incorporar LOOH o CP a los marcadores de la enfermedad tradicionales en AR, bien por separado o ambos conjuntamente, mejoró el diagnóstico de AR, especialmente en los pacientes no fumadores o aquellos con anticuerpos anti- CCP negativos.background. Besides the development of new markers and di- agnostic criteria for rheumatoid arthritis (RA), many patients are still diagnosed after several years of symptoms. Oxidative stress markers are already increased at an early stage of RA. Our aim was to evaluate the additional diagnostic value of these markers. Methods. A case-control study was performed. Patients met the 1987 RA ACR criteria, less than 2 years of symptoms and no previous treatment with disease-modifying anti-rheumatic drugs (DMARD), steroids or vitamin E. Controls were select- ed from patient’s relatives and matched (1:1) by gender, age, and current smoking habit. Oxidative damage markers were malonyldialdehyde (MDA), Lipid hydroperoxides (LOOH) and Carbonyl proteins (CP). Statistical analysis was performed in agreement with the STARD initiative. results. Sixty-five RA patients without treatment and 65 healthy controls were included. LOOH, CP, antibodies against citrullinated peptides (anti-CCP) and rheumatoid factor (RF) were significantly higher in patients, and MDA higher in con- trols. The same results were obtained in the subgroups of pa- tients who smoke or not, and in anti-CCP positive or negative. The diagnosis performance of traditional markers showed good specificity but low sensitivity. The addition of LOOH and CP increased the sensitivity and the area under the receiving operating characteristic (ROC) curve especially in non-smok- ing (66%) and negative anti-CCP (51%) patients. conclusions. The separate or combined addition of LOOH or CP to the traditional disease markers improved the diag- nosis of RA, especially in non-smoking or negative anti-CCP patients

Schwann cells and mesenchymal stem cells in laminin- or fibronectin-aligned matrices and regeneration across a critical size defect of 15 mm in the rat sciatic nerve

OBJECTIVE Artificial nerve guides are being developed to substitute for autograft repair after peripheral nerve injuries. However, the use of conduits is limited by the length of the gap that needs to be bridged, with the success of regeneration highly compromised in long gaps. Addition of aligned proregenerative cells and extracellular matrix (ECM) components inside the conduit can be a good strategy to achieve artificial grafts that recreate the natural environment offered by a nerve graft. The purpose of this study was to functionalize chitosan devices with different cell types to support regeneration in limiting gaps in the rat peripheral nerve. METHODS The authors used chitosan devices combined with proteins of the ECM and cells in a rat model of sciatic nerve injury. Combinations of fibronectin and laminin with mesenchymal stem cells (MSCs) or Schwann cells (SCs) were aligned within tethered collagen-based gels, which were placed inside chitosan tubes that were then used to repair a critical-size gap of 15 mm in the rat sciatic nerve. Electrophysiology and algesimetry tests were performed to analyze functional recovery during the 4 months after injury and repair. Histological analysis was performed at the midlevel and distal level of the tubes to assess the number of regenerated myelinated fibers. RESULTS Functional analysis demonstrated that SC-aligned scaffolds resulted in 100% regeneration success in a 15-mm nerve defect in this rat model. In contrast, animals that underwent repair with MSC-aligned constructs had only 90% regeneration success, and those implanted with acellular bridges had only 75% regeneration success. CONCLUSIONS These results indicate that the combination of chitosan conduits with ECM-enriched cellular gels represents a good alternative to the use of autografts for repairing long nerve gaps

Physical activity practice and attitudes in canarian teenagers

En el presente estudio de la población adolescente de la Comunidad Autónoma de Canarias, se evidencia que aquellos adolescentes que cumplen con las recomendaciones de práctica de Actividad Física tanto de intensidad moderada como vigorosa frente a los que no las cumplen, muestran a su vez mejores valores en la percepción del conjunto de actitudes que influyen en los niveles de práctica; competencia motriz, disfrute y valor-utilidad otorgada a la misma. Lo cual nos permite afirmar que este conjunto de factores pueden determinar el tipo y grado de participación en actividades físico-deportivas en este sector de la poblaciónIn this actual study of the adolescent population of the Autonomous Region of the Canary Islands, is evident, that teens who comply with the recommendations of practice of physical activity both of moderate intensity as vigorous intensity, compared with those which do not comply, show the best values in the perception of the set of attitudes that influence the levels of practice; perceived competence, enjoyment, perceived value. Which allows us to affirm that this set of factors can determine the type and degree of participation in physical-sport activities in this sector of the populatio