De retibus socialibus et legibus momenti

Online Social Networks (OSNs) are a cutting edge topic. Almost everybody --users, marketers, brands, companies, and researchers-- is approaching OSNs to better understand them and take advantage of their benefits. Maybe one of the key concepts underlying OSNs is that of influence which is highly related, although not entirely identical, to those of popularity and centrality. Influence is, according to Merriam-Webster, "the capacity of causing an effect in indirect or intangible ways". Hence, in the context of OSNs, it has been proposed to analyze the clicks received by promoted URLs in order to check for any positive correlation between the number of visits and different "influence" scores. Such an evaluation methodology is used in this paper to compare a number of those techniques with a new method firstly described here. That new method is a simple and rather elegant solution which tackles with influence in OSNs by applying a physical metaphor.Comment: Changes made for third revision: Brief description of the dataset employed added to Introduction. Minor changes to the description of preparation of the bit.ly datasets. Minor changes to the captions of Tables 1 and 3. Brief addition in the Conclusions section (future line of work added). Added references 16 and 18. Some typos and grammar polishe

Ediacaran Obduction of a Fore-Arc Ophiolite in SW Iberia: A Turning Point in the Evolving Geodynamic Setting of Peri- Gondwana

The Calzadilla Ophiolite is an ensemble of mafic and ultramafic rocks that represents the transition between lower crust and upper mantle of a Cadomian (peri-Gondwanan) fore arc. Mapping and structural analysis of the ophiolite demonstrates that it was obducted in latest Ediacaran times, because the Ediacaran-Early Cambrian sedimentary series (Malcocinado Formation) discordantly covers it. The ophiolite and emplacement-related structures are affected by Variscan deformation (Devonian-Carboniferous), which includes SW verging overturned folds (D1) and thrusts (D2), upright folds (D3), extensional faults (D4), and later faults (D5). These phases of deformation are explained in the context of Variscan tectonics as the result of the progressive collision between Gondwana and Laurussia. Qualitative unstraining of Variscan deformation reveals the primary geometry of Ediacaran-Cambrian structures and uncovers the generation of east verging thrusts as responsible for the primary obduction of the Calzadilla Ophiolite. Restoration of planar and linear structures associated with this event indicates an Ediacaran, east directed obduction of the ophiolite, that is, emplacement of the Cadomian fore arc onto inner sections of the northern margin of Gondwana. According to regional data, the obduction separates two extension-dominated stages in the tectonic evolution of the African margin of northern Gondwana preserved in southern Europe. Preobduction extension brought about the onset and widening of fore-arc and back-arc basins in the external part of the continent, while postobduction extension facilitated the formation of extensional migmatitic domes, an oceanward migration of back-arc spreading centers across peri-Gondwana, and the eventual opening of a major basin such as the Rheic Ocean

Composition and Petrologic significance of Biotites and muscovites from the granitoids of the Boal-Los Ancares Metamorphic Belt (Westasturian Leonese Zone)

[Resumen] Las biotitas de los granitoides peralumínicos de la banda metamórfica Boal-Los Ancares se sitúan en el dominio de las biotitas s.s. con contenidos en Aliv que socilan entre 2.3 y 2.65 Yvalores de Fe/Fe + Mg entre 0.42 y 0.85. La variación composicional está controlada esencialmente por mecanismos de sustitución cati6nicaacoplada. La sustitución 3(R2+ti=2Alvi5+Ovi es más eficaz que la sustitución Al-Tschermak. La entraa3. de Ti en posiciones octaédricas está controlada por la sustitución 2Alvi=(Ti4+)vi +(R2+ Ji. La composición de las biotitas en base a sus contenidos en Al y Mg permite diferenciar tres grupos de granitoides, en concordancia con su mineralogía y composición de roca total. La variación composicional de la moscovita se produce principalmente a través de las sustituciones fengítica y paragonítica. El contenido máXimo en molécula cela~donítica es de 25 0A» Yel contenido máXimo en molécula paragonítica es de 12 %. Ni los caracteres texturales ni la composición química de este mineral constituyen un criterio definitivo en muchos casos para establecer su formación en el estadio magmático del sistema o bien en estadios posteriores. La composición de la moscovita en leucogranitos y aplitas sin biotita muestra notables particularidades con relación a la composición de este mineral en granitos de dos micas. Estas diferencias son manifiestas en las proporciones Ti:Mg:Na y Ti:Fe:Mg, las cuales muestran una buena correlación con algunos parámetros composicionales de roca total.[Abstract] Biotites from the peraluminous granitoids of the Boal-Los Ancares metamporphic band plot in the field ofbiotites s.s. with Aliv contents between 2.3 and 2.65 and Fe/Fe + Mg values ranging from 0.42 to 0.85. Compositional variation is basically controlled by coupled substitutional mechanisms. Substitution 3(R2+Yi =2Alvi+(Yi is more efficient than the Al-Tschermak substitution. Ti enters the octahedral sites via the 2Alvi = (Ti4+)vi+(R2+Yi substitution. The composition of biotites on the basis of Al and Mg contents pfudiscriminates three granitoid groups, this in agreement with their respective mineralogical composition and whole rock chemistry. Muscovite compositional variation is essentially due to the phengitic and paragonitic substitutions. The maxímum celaduníte content is 25 O/o and the maximum paragonite content is 12 %. Neither textural criteria nor chemical compositiori consitute unequivocal criteria for establishing the magmatic or submagmatic origin of the studied muscovites. Muscovite composition in biotite-free leucogranites and aplites shows distinctive features with respect to two-mica granites. This is particularly noticeable in the Ti:Mg:Na and Ti:Fe:Mg ratios, which correlate well with sorne whole rock compositional parameter

Cierre quirúrgico en flexión versus extensión en artroplastias totales de rodilla

Se ha realizado un estudio prospectivo de 44 pacientes con gonartrosis primaria que fueron intervenidos con artroplastia total de rodilla con el objeto de determinar las diferencies en cuanto a la movilidad final de la rodilla dependiendo del cierre quirúrgico en flexión o en extensión. Se formaron dos grupos con similares características de homogeneidad respecto al sexo, edad, peso corporal y arco de movilidad previa, no existiendo diferencies significativas entre los grupos en la valoración preoperatoria. En el primer grupo se incluyeron 22 pacientes donde se había realizado la sutura de la cápsula articular y del plano muscular y cutáneo en flexión de 70º a 90º; el segundo grupo estaba formado por otros 22 pacientes en los que se realizó la sutura con la rodilla en extensión completa. En todos los pacientes se implantó el mismo modelo artroplástico y todos siguieron el mismo protocolo de rehabilitación postoperatoria. La evaluación clínica se realizó en el momento del alta hospitalaria, al mes, tres y seis meses, siguiendo la escala del Hospital for Special Surgery. Se apreció un arco de movilidad y puntuación clínica mayor en el grupo de rodillas suturadas en extensión, con una diferencia estadísticamente significativa, en los controles realizados en el alta hospitalaria y al mes de la intervención. A los seis meses no se apreciaron diferencias entre ambos grupos. La posición de la rodilla en el cierre quirúrgico de una artroplastia no afecta a su funcionalidad.In a prospective study, 44 patients with primary osteoarthritis of the knee undergoing total knee arthroplasty were compared to determine whether surgical closure of the entire wound in flexion had any effect on the postoperative range of motion over a period of six months. In twenty-two patients the knee was surgically closed in 70º to 90º flexion. In the second group of 22 patients, knees were closed in extension. There was no significant difference between groups respect to age, gender, weight and preoperative range of motion. All of the patients were operated on by the same team of surgeons and with the same type of prosthesis. Both groups of patients received a standardized exercise program during their hospitalization. All patients were evaluated following the parameters of the Hospital for Special Surgery score at discharge from the hospital, at first month, third and sixth month after operation. At all the intervals, both the flexion measurements and function scores were better in the flexion closure group, although we only found statically significant difference at discharge and at the first month postoperatively. The position of the knee in the surgical closing of an arthroplasty doesn't affected o functionality

Thermal 3D CFD Simulation with Active Transparent Façade in Buildings

In recent years active façades have acquired greater importance given their capacity to improve the energy efficiency of buildings. One such type is the so-called Active Transparent Façade (ATF). A 3D numerical model based on computational fluid dynamics (CFD) and the Finite Element Method (FEM) has been generated to simulate the thermal performance of buildings equipped with this type of façade. This model is introduced for general application and allows the design parameters to be adapted for this system. The case study of Le Corbusier’s proposal for the City of Refuge in Paris, the clearest example of previous use of an ATF is examined. In addition, a proposal is presented for the energy improvement of Le Corbusier’s original solution. In order to do so, the conditions for the supply of air into the ATF cavity and in the mechanical ventilation system are assessed to guarantee comfort conditions

Thermal 3D CFD Simulation with Active Transparent Façade in Buildings

In recent years active façades have acquired greater importance given their capacity to improve the energy efficiency of buildings. One such type is the so-called Active Transparent Façade (ATF). A 3D numerical model based on computational fluid dynamics (CFD) and the Finite Element Method (FEM) has been generated to simulate the thermal performance of buildings equipped with this type of façade. This model is introduced for general application and allows the design parameters to be adapted for this system. The case study of Le Corbusier’s proposal for the City of Refuge in Paris, the clearest example of previous use of an ATF is examined. In addition, a proposal is presented for the energy improvement of Le Corbusier’s original solution. In order to do so, the conditions for the supply of air into the ATF cavity and in the mechanical ventilation system are assessed to guarantee comfort conditions

Academic Success and Student Satisfaction with University Teaching

This study uses surveys to assess student academic success in relation to the teaching activity of the University staff. The main goal is to test how the student’s degree of satisfaction of with their teachers can be considered dependent on the success the student obtains in each subject. The results show that the students are more satisfied with their teaching when they have a higher rate of success, although in some optional courses, the degree of satisfaction diminishes with the higher rate of success. The course expectations, when defined by the difference between achievement and success, impact the student satisfaction with the teaching

Fibromatosis agresiva en hueco popliteo: A propósito de un caso

Se presenta un caso de una masa indolora en región posterior de la pierna en un varón de 35 años de crecimiento rápido, consistencia firme y mal delimitada. La resonancia magnética mostraba infiltración de músculos y tejido cellar subcutáneo, siendo sugestiva de fibromatois, tumor neurogénico o sarcoma de partes blandas. La biopsia incisional confirmó el diagnóstico de fibromatiosis agresiva. La resección amplia es el tratamiento aconsejado por la mayoría de autores, aunque en algunos casos y debido al carácter infiltrativo de la lesión es difícil resecarla ampliamente. La radioterapia se aconseja en los casos de resección y en los casos de recidiva.We present a case of a 35 year-old man who presented a fast growing painless mass localized in the posterior leg, which had at physical examination poorly defined contour and firm consistency. Magnetic resonance imaging showed local infiltration of muscle and subcutaneous cellular tissue, being suggestive of fibromatosis, neurogenic tumour, or soft tissue sarcoma. The incision biopsy confirmed the diagnosis of aggressive fibromatosis. Wide resection is the treatment recommended by most authors, although in some cases and due to the infiltration tendency of the tumour, it is difficult to achieve wide margins. Post-operative radiotherapy is recommended in cases of marginal resection and in case of recurrence

Profiles of women who have suffered occupational accidents in cleaning: perceived health, psychosocial risks, and personality variables

Purpose: The main goal was to identify the variables (sociodemographic, work, psychosocial, perceived health, and personality) associated with occupational accidents suffered in the past by women in the cleaning sector. Methods: A sample of 455 women was evaluated. Results: A total of 23.5% of the workers (n = 107) had suffered an occupational accident with medical leave. In general, women who had suffered some accident in their life had a worse situation in all areas evaluated. Two subsamples of women had a greater association with accidents. Specifically, the presence of work accidents was 15.9 times higher among those who presented a worse perception of their physical effort and a greater tendency towards risky behaviours and 13.5 times higher among those who had a moderate perception of physical exertion and a disability. Conclusion: In general, the characteristics of female workers were found to be associated with different accident rates. Preventive actions should be designed individually