Open Strings in IIB Orientifold Reductions

We consider type IIB compactifications on a general 4D group manifold with different types of possible spacetime filling O-planes and the corresponding D-branes parallel to them. Once fluxes allowed by the associated orientifold projection are included, a 6D $\mathcal{N}=(1,1)$ gauged supergravity is obtained. In this paper we show how the consistent coupling to dynamical open strings living on the spacetime filling D-branes may be captured by the inclusion of extra vector multiplets and extra embedding tensor deformations on the gauged supergravity side. As a result, the quadratic constraints on the embedding tensor consistently reproduce the source corrected 10D Bianchi identities. Furthermore, the field strength modifications induced by the open string sector could potentially be understood as U-dual versions of the Green-Schwarz terms. Finally, the entire scalar potential of the theory exactly matches the one obtained from reduction of the bulk action plus the source contributions.Comment: 45 pages, 1 figur

Tratamiento del choque femoroacetabular mediante miniabordaje anterior. Resultados a corto plazo

El tratamiento quirúrgico del choque femoroacetabular (CFA) es un práctica clínica cada vez más frecuente en nuestra especialidad. Objetivo. Analizar los resultados clínicos y radiológicos de una primera serie de pacientes diagnosticados de CFA intervenidos mediante miniabordaje anterior. Material y métodos. Estudio prospectivo de 30 pacientes con una edad media de 36,2 años y un seguimiento mínimo de 12 meses. La valoración clínica se ha realizado mediante las escalas SF-36, WOMAC y NAHS. Evaluamos la corrección radiológica de la deformidad y la progresión o no del grado de coxartrosis. Resultados. Se obtuvo una corrección adecuada de la deformidad en el 93% de los casos, 27 de los 30 pacientes presentaron una mejoría clínica significativa en los test realizados. La complicación más frecuente fue la meralgia parestésica del femorocutáneo (5 casos), 1 paciente precisó de sustitución protésica por evolución del grado de coxartrosis. Conclusiones. El tratamiento del CFA mediante mini abordaje anterior es un procedimiento seguro y reproducible. Permite la corrección de las anormalidades anatómicas y la obtención de resultados clínicos satisfactorios en una cohorte de pacientes jóvenes.Surgical treatment of femoroacetabular impingement (FAI) is an increasingly common clinical practice in our speciality. Aim. To analyze the clinical and radiological results of a first series of patients diagnosed with a FAI treated with anterior mini-open approach. Material and methods. Prospective study of 30 patients with a mean age of 36.2 years with a minimum follow-up of 12 months was made. Clinical assessment was performed using the SF-36, WOMAC and NAHS scales. We evaluate the correction of the radiologic deformity and progression of the osteoarthritis grade. Results. An adequate correction of the deformity in 93% of cases was obtained, 27 of the 30 patients showed significant clinical improvement in all tests performed. The most common complication was meralgia paresthesia of the femoro-cutaneous nerve (5 cases), 1 patient required prosthetic replacement for progression of the osteoarthritis grade. Conclusions. FAI treatment by mini-open approach is a safe and reproducible procedure. This technique allows correction of anatomical abnormalities and obtains satisfactory clinical outcomes in a cohort of young patients

A computational study on the intriguing mechanisms of the gas-phase thermal activation of methane by bare [Ni(H)(OH)](+)

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.A detailed computational study on the reaction mechanisms of the thermal activation of methane by the bare complex [Ni(H)(OH)]+ has been conducted. The experimentally observed reaction features, i.e. the ligand exchange Ni(H) → Ni(CH3), the H/D scrambling between the incoming methane and the hydrido ligand of the nickel complex, the spectator-like behavior of the OH ligand, and the relatively moderate reaction efficiency of 6% relative to the collision rate of the ion/molecule reaction, can be explained by considering three competing mechanisms, and a satisfactory agreement between experiment and theory has been found.DFG, EXC 314, Unifying Concepts in Catalysi

Evaluation of a Learning Analytics Application for Open edX Platform

Massive open online courses (MOOCs) have recently emerged as a revolution in education. Due to the huge amount of users, it is difficult for teachers to provide personalized instruction. Learning analytics computer applications have emerged as a solution. At present, MOOC platforms provide low support for learning analytics visualizations, and a challenge is to provide useful and effective visualization applications about the learning process. At this paper we review the learning analytics functionality of Open edX and make an overview of our learning analytics application ANALYSE. We present a usability and effectiveness evaluation of ANALYSE tool with 40 students taking a Design of Telematics Applications course. The survey obtained very positive results in a system usability scale (SUS) questionnaire (78.44/100) in terms of the usefulness of visualizations (3.68/5) and the effectiveness ratio (92/100) of the actions required for the respondents. Therefore, we can conclude that the implemented learning analytics application is usable and effective.Acknowledgements: This work has been supported by the "eMadrid" project (Regional Government of Madrid) under grant S2013/ICE-2715, the "RESET" project (Ministry of Economy and Competiveness) under grant RESET TIN2014-53199-C3-1-R and the European Erasmus+ SHEILA project under grant 562080-EPP-1-2015-BE-EPPKA3-PI-FORWARD

Case Report Skin Abscess due to Serratia marcescens in an Immunocompetent Patient after Receiving a Tattoo

The incidence of skin infections caused by Serratia marcescens is extremely low and such infections are typically observed in immunocompromised patients. The clinical manifestations of these infections include cellulitis, abscesses, fluctuant nodules, or granulomatous lesions. Infections caused by S. marcescens are very difficult to treat due to their resistance to many antibiotics, which often leads to specific and prolonged treatment. Infections after receiving a tattoo are very rare and are caused by unhygienic conditions or the inexperience of the tattooist. In this paper we present the case of a 32-year-old male with no comorbidity, who presented an abscess caused by S. marcescens in a area that was tattooed one month earlier. The case was resolved with surgery and antimicrobial therapy that was based on the antibiogram. To our knowledge, this is the first reported case of a S. marcescens skin infection following a tattoo, in the absence of immunosuppression

Mapping rootable depth and root zone plant-available water holding capacity of the soil of sub-Saharan Africa

In rainfed crop production, root zone plant-available water holding capacity (RZ-PAWHC) of the soil has a large influence on crop growth and the yield response to management inputs such as improved seeds and fertilisers. However, data are lacking for this parameter in sub-Saharan Africa (SSA). This study produced the first spatially explicit, coherent and complete maps of the rootable depth and RZ-PAWHC of soil in SSA. We compiled georeferenced data from 28,000 soil profiles from SSA, which were used as input for digital soil mapping (DSM) techniques to produce soil property maps of SSA. Based on these soil properties, we developed and parameterised (pedotransfer) functions, rules and criteria to evaluate soil water retention at field capacity and wilting point, the soil fine earth fraction from coarse fragments content and, for maize, the soil rootability (relative to threshold values) and rootable depth. Maps of these secondary soil properties were derived using the primary soil property maps as input for the evaluation rules and the results were aggregated over the rootable depth to obtain a map of RZ-PAWHC, with a spatial resolution of 1 km2. The mean RZ-PAWHC for SSA is 74mm and the associated average root zone depth is 96 cm. Pearson correlation between the two is 0.95. RZ-PAWHC proves most limited by the rootable depth but is also highly sensitive to the definition of field capacity. The total soil volume of SSA potentially rootable by maize is reduced by one third (over 10,500 km3) due to soil conditions restricting root zone depth. Of these, 4800 km3 are due to limited depth of aeration, which is the factor most severely limiting in terms of extent (km2), and 2500 km3 due to sodicity which is most severely limiting in terms of degree (depth in cm). Depth of soil to bedrock reduces the rootable soil volume by 2500 km3, aluminium toxicity by 600 km3, porosity by 120 km3 and alkalinity by 20 km3. The accuracy of the map of rootable depth and thus of RZ-PAWHC could not be validated quantitatively due to absent data on rootability and rootable depth but is limited by the accuracy of the primary soil property maps. The methodological framework is robust and has been operationalised such that the maps can easily be updated as additional data become available

Vástagos monobloque de recubrimiento completo en cirugía de revisión femoral. Resultados a largo plazo de 80 casos.

Bone stock lost and anatomical changes in the proximal femur make femoral revision surgery a complex procedure where the implant chooses will be essential. With the aim of evaluating the clinical and radiological results of the fully coated monoblock stems, we retrospectively studied 80 consecutive cases of femoral revision surgery operated by our hip team. The mean follow-up was 8.6 years. The average score on the Harris Hip Score was 81,2 points. We achieved better results in patients with less bone defects (Paprosky I, II and IIIA) in contrast to those with Paprosky type IIIB defects (p=0.005), in patients with a single previous surgery (p=0.031), in patients under 65 years (p=0.009) and in those who did not suffer complications (p=0.024). The survival rate was 96.1% at 10 years if we consider as failure the removal of the stem due to aseptic loosening and 89.9% if we consider revision of the stem as a failure due to any cause. After the results obtained, we think that fully coated stems provide a solid and stable fixation in femoral revision surgery. However, worst results obtained in patients with bigger bone defects make other options to be considered