Memoria y filosofía de la historia en Walter Benjamin: reflexiones sobre el progreso, la modernidad y el Holocausto

El presente estudio pretende utilizar la filosofía de la historia de Walter Benjamin como prisma hermenéutico a través del cual interpretar la evolución conceptual de categorías culturales como la de “progreso” y “modernidad” y fenómenos históricos como las condiciones de posibilidad del Holocausto y su rememoración durante el último medio siglo. Dicho trauma histórico permite estudiar tres fenómenos: (1) la ruptura epistemológica que significó la Solución Final y la reflexión que conlleva sobre la condición humana; (2) un análisis de los límites de la representación de su horror en la sociedad postmoderna actual y (3) la relación que tuvo con los valores preconizados desde el siglo de las Luces, principios que debían conducirnos a un mayor grado de libertad y autonomía y que llevaron al hombre a exterminar a sus semejantes mediante la aplicación de la llamada razón instrumental

Waste and Recycled Materials and their Impact on the Mechanical Properties of Construction Composite Materials

In a world increasingly fixated on the demands of sustainable development, too much attention has been focused on the widely used building materials, mainly on those tools and strategies for their reuse and those characteristics for considering them as environmental-friendly materials. Among the strategies are the following: (a) increased reliability on waste and recycled materials—such action will have to incorporate the substitution of recycled for virgin materials; (b) improved durability through reduction of materials needed for their replacement; and (c) improved mechanical properties, which reduces the use of raw materials. Extensive research and development activities in recycling composite materials have been conducted, and various technologies have been developed: (a) mechanical recycling, (b) thermal recycling, and (c) chemical recycling. However, gamma radiation is an innovative and clean technology, alternative to conventional recycling procedures. Gamma irradiation has proved to be an adequate tool for modifications of the physicochemical properties of polymers, through different effects: (a) scission, branching as well as cross-linking of polymer chains and (b) oxidative degradation. Moreover, the reuse and recycling of waste materials and the use of gamma radiation are useful tools for improving the mechanical properties of concrete. In this chapter, we show results of the effects of gamma irradiation on the physicochemical properties of waste and recycled materials and their reuse to enhance the properties of construction composite materials

Co-existence of peripheral fatigue of the knee extensors and jump potentiation after an incremental running test to exhaustion in endurance trained male runners

[EN] The aim of the present study was to investigate the effect of an incremental running exercise until exhaustion on twitch responses and jump capacity in endurance trained runners. For this purpose, 8 experienced endurance male runners were required to perform neuromuscular function tests before and after a submaximal running bout (control condition -CTR-) or an incremental running test to volitional exhaustion (experimental conditions -EXP-). The twitch interpolation technique was used to assess voluntary activation and muscle contractile properties before and after each condition (CTR and EXP). Countermovement jump was also used to assess the stretch-shortening cycle function before and after both conditions. In addition, rating of perceived exertion, heart rate, blood lactate and skin temperature were also recorded. Only EXP improved jump performance, however, it was also accompanied by a reduction in maximal voluntary contraction and the peak twitch force of the knee extensors evoked by electrical stimulation at 10 Hz (Db10). It is likely that reductions in maximal voluntary contraction may be related to an excitation- contraction coupling failure (i.e. low-frequency fatigue) as suggest the reduction in the Db10. The current results confirm that acute changes in jump performance may not be appropriate to evaluate acute fatigue in endurance trained runner

Torque de desinserción y propiedades fisico-químicas de implantes dentales grabados con ácidos fluorhídrico y nítrico: estudio experimental en perros Beagle

Objetivo: Estudiar la composición, características superficiales y respuesta al torque de desinserción de una superficie implantaria tratada inicialmente con ácido fluorhídrico y posterior pasivado con ácidos fluorhídrico y nítrico. Diseño del estudio: En una primera fase, se seleccionaron 12 implantes en los que se estudiaron las características fisico-químicas mediante mediciones de energía dispersa de rayos X (EDS), microscopio electrónico de barrido y análisis de XPS (espectrometría de fotoelectrones). Asimismo, se colocaron 24 implantes 'doce de 8 mm y doce de 10 mm de longitud-, en seis perros beagle, en los que tras un período de reposo, se procedió a la retirada de 12 implantes a las seis semanas y los 12 restantes a las doce semanas, mediante un calibrador de torque Gauge TonichiR modelo BGT150CN-S -con un rango de registro de fuerza de 0 a 150 Ncm. Resultados: El análisis de la composición química superficial mediante EDS sólo mostró la presencia de titanio en las superficies grabadas. En el análisis mediante XPS, al igual que sucede con las superficies de otros implantes dentales, aparecieron trazas de otros elementos presentes en la superficie, fundamentalmente de carbono. La morfología de la superficie tras el doble grabado con ácido, permitió observar la rugosidad creada por el ataque ácido, con una morfología bastante homogénea. Los valores de rugosidad obtenidos fueron superiores al micrómetro. Los valores medios encontrados para el torque de desinserción, a las seis semanas, fueron de 79,7 Ncm para los implantes de 8 mm de longitud y 115 Ncm para los implantes de 10 mm. A las doce semanas, estos valores incrementaron hasta 101,2 Ncm para los implantes de 8 mm y 139,7 Ncm para los implantes de 10 mm de longitud. Conclusiones: El grabado con ácido fluorhídrico y nítrico, posee características superficiales óptimas y comparables al de otras superficies. Los valores de torque de desinserción abren la posibilidad para su aplicación en clínica humana para procedimientos de carga precoz o inmediata.Objective: To study the composition, surface characteristics and response to removal torque of an implant surface subjected to hydrofluoric acid etching and posterior passivating with hydrofluoric and nitric acid. Study design: Twelve implants were initially selected and their physico-chemical characteristics were evaluated by means of energy-dispersive X-rays (EDS), scanning electron microscopy (SEM) and photoelectron spectroscopy (XPS). In addition, 24 implants ' 12 measuring 8 mm and 12 measuring 10 mm in length ' were implanted in 6 Beagle dogs. Twelve implants were removed after a recovery period of 6 weeks, followed by removal of the remaining 12 implants after 12 Medeweeks, using a torque calibrator (Gauge Tonichi® model BGT150CN-S) with a force registry range of 0-150 Ncm. Results: EDS analysis of the surface chemical composition only revealed the presence of titanium in the etched surfaces. In the same way as with the surfaces of other dental implants, XPS analysis revealed traces of other elements present in the surface, fundamentally carbon. Following dual acid etching, the surface showed the roughness resulting from acid action, with a morphology that proved to be quite homogeneous. The roughness values obtained exceeded 1 ìm. The mean removal torque values after 6 weeks were 79.7 Ncm for the 8 mm implants and 115 Ncm for the 10 mm implants. After 12 weeks, these values increased to 101.2 Ncm and 139.7 Ncm, respectively. Conclusions: Hydrofluoric and nitric acid etching affords optimum surface characteristics comparable to those of other surfaces. The recorded removal torque values raise the possibility of human clinical application for early or immediate loading procedures

Hydrocarbon biodegradation and dynamic laser speckle for detecting chemotactic responses at low bacterial concentration

We report on the biodegradation of pure hydrocarbons and chemotaxis towards these compounds by an isolated chlorophenol degrader, Pseudomonas strain H. The biochemical and phylogenetic analysis of the 16S rDNA sequence identified Pseudomonas strain H as having 99.56% similarity with P. aeruginosa PA01. This strain was able to degrade n-hexadecane, 1-undecene, 1-nonene, 1-decene, 1-dodecene and kerosene. It grew in the presence of 1-octene, while this hydrocarbons is toxic to other hydrocarbons degraders. Pseudomonas strain H was also chemotactic towards n-hexadecane, kerosene, 1-undecene and 1-dodecene. These results show that this Pseudomonas strain H is an attractive candidate for hydrocarbon-containing wastewater bioremediation in controlled environments. Since the classical standard techniques for detecting chemotaxis are not efficient at low bacterial concentrations, we demonstrate the use of the dynamic speckle laser method, which is simple and inexpensive, to confirm bacterial chemotaxis at low cell concentrations (less than 105 colony-forming unit per millilitre (CFU/mL)) when hydrocarbons are the attractants.Fil: Nisenbaum, Melina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata; ArgentinaFil: Sendra, Gonzalo Hernán. Universidad Nacional de Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Gilbert, Gastón Alfredo Cerdá. Obras Sanitarias Mar del Plata; ArgentinaFil: Scagliola, Marcelo. Obras Sanitarias Mar del Plata; ArgentinaFil: González, Jorge Froilán. Universidad Nacional de Mar del Plata; ArgentinaFil: Murialdo, Silvia Elena. Universidad Nacional de Mar del Plata; Argentin

ALTERNATIVAS PARA SUPLIR LA CARENCIA DE FÓSFORO EN FRESA Y DISMINUIR LA CONTAMINACIÓN AMBIENTAL EN PAMPLONA NORTE DE SANTANDER

El presente trabajo tuvo como objetivo evaluar seis bioproductos locales como alternativas orgánicas para suplir la carencia de fósforo en fresa, en Pamplona – Norte de Santander. Se desarrolló un ensayo de campo con ocho tratamientos, seis biopreparados elaborados por ASPAGRO, un fertilizante químico convencional (Folyfos) y un testigo. Caldo Rizósfera y M6 mostraron mayor disminución en la incidencia y severidad de la deficiencia de fósforo, comparados con el testigo y los demás tratamientos. Los tratamientos Caldo Rizósfera y M6 se destacaron con relación a la mayor concentración de fosforo foliar, con una correlación negativa y significativa con la incidencia y la severidad de los síntomas de la deficiencia de fósforo

On the relationship between atmospheric rivers, weather types and floods in Galicia (NW Spain)

Atmospheric rivers (ARs) – long and narrow structures of anomalously high water vapor flux located in the warm sector of extratropical cyclones – have been shown to be closely related to extreme precipitation and flooding. In this paper we analyze the connection between ARs and flooding in the northwestern Spanish region of Galicia under a variety of synoptic conditions represented by the so-called “weather types”, a classification of daily sea-level pressure patterns obtained by means of a simple scheme that adopts the subjective procedure of Lamb. Flood events are identified from official reports conducted by the Spanish emergency management agency (Protección Civil) from 1979 to 2010. Our results suggest that, although most flood events in Galicia do not coincide with the presence of an overhead AR, ARs are present in the majority of severe cases, particularly in coastal areas. Flood events associated with ARs are connected to cyclonic weather types with westerly and southwesterly flows, which occur mostly in winter months. The link between ARs and severe flooding is not very apparent in inland areas or during summer months, in which case heavy precipitation is usually not frontal in nature but rather convective. Nevertheless, our results show that, in general, the amount of precipitation in flood events in Galicia more than doubles when an AR is present.Ministerio de Economía y Competitividad | Ref. CGL2013-45932-RXunta de Galicia | Ref. ED431C 2017/64-GR

Cálculo y transmisión de datos de tiro para un grupo de artillería en misión de apoyo directo

El trabajo escrito en esta memoria ha estado marcado por la reestructuración que está sufriendo el Ejército de Tierra. El futuro del Ejercito son las Brigadas Orgánicas Polivalentes donde los Grupos de Artillería de Campaña estarán equipados con medios heterogéneos. Esta novedad va a generar en los métodos de transmisión y cálculo de tiro, dentro del Mando y Control de Artillería de Campaña, grandes cambios y retos que tendrá que afrontar. En esta investigación, realizada en el Grupo de Artillería De Campaña II de la Legión, se analizan los medios y procedimientos disponibles que tiene un Grupo de artillería para llevar a cabo la transmisión y el cálculo de datos de tiro en teatro de operaciones, se explican los nuevos cambios en orgánica que van a sufrir los Grupos de Artillería para poder comprender el trabajo en su totalidad y por último se comprueba cómo no siempre los medios de cálculo y transmisión de datos de tiro que tienen los Obuses 155/52 SIAC son la mejor opción por ser la herramienta más precisa. Todo depende de la misión que tenga el Grupo de Artillería, y las prioridades en el combate.<br /

Removal torque and physico-chemical characteristics of dental implants etched with hydrofluoric and nitric acid : an experimental study in Beagle dogs

Objective: To study the composition, surface characteristics and response to removal torque of an implant surface subjected to hydrofluoric acid etching and posterior passivating with hydrofluoric and nitric acid. Study design: Twelve implants were initially selected and their physico-chemical characteristics were evaluated by means of energy-dispersive X-rays (EDS), scanning electron microscopy (SEM) and photoelectron spectroscopy (XPS). In addition, 24 implants ? 12 measuring 8 mm and 12 measuring 10 mm in length ? were implanted in 6 Beagle dogs. Twelve implants were removed after a recovery period of 6 weeks, followed by removal of the remaining 12 implants after 12 weeks, using a torque calibrator (Gauge Tonichi® model BGT150CN-S) with a force registry range of 0-150 Ncm. Results: EDS analysis of the surface chemical composition only revealed the presence of titanium in the etched surfaces. In the same way as with the surfaces of other dental implants, XPS analysis revealed traces of other elements present in the surface, fundamentally carbon. Following dual acid etching, the surface showed the roughness resulting from acid action, with a morphology that proved to be quite homogeneous. The roughness values obtained exceeded 1 µm. The mean removal torque values after 6 weeks were 79.7 Ncm for the 8 mm implants and 115 Ncm for the 10 mm implants. After 12 weeks, these values increased to 101.2 Ncm and 139.7 Ncm, respectively. Conclusions: Hydrofluoric and nitric acid etching affords optimum surface characteristics comparable to those of other surfaces. The recorded removal torque values raise the possibility of human clinical application for early or immediate loading procedures