Solar neutrino detection

More than 40 years ago, neutrinos where conceived as a way to test the validity of the solar models which tell us that stars are powered by nuclear fusion reactions. The first measurement of the neutrino flux, in 1968 in the Homestake mine in South Dakota, detected only one third of the expected value, originating what has been known as the Solar Neutrino Problem. Different experiments were built in order to understand the origin of this discrepancy. Now we know that neutrinos undergo oscillation phenomenon changing their nature traveling from the core of the Sun to our detectors. In the work the 40 year long saga of the neutrino detection is presented; from the first proposals to test the solar models to last real time measurements of the low energy part of the neutrino spectrum.Comment: 8 pages, 5 figures. III School on Cosmic Rays and Astrophysics August 25 to September 5, 2008 Arequipa (Peru) AIP conference proceedin

Estudio in vitro

Tesis (Cirujano Dentista)La obtención de una mayor y prolongada resistencia adhesiva en restauraciones indirectas de cerámica es un requisito para el éxito clínico. Existe una amplia variedad de cementos dentales y es necesario comparar y estudiar sus propiedades. Objetivo: Evaluar la resistencia adhesiva al microcizallamiento entre los cementos adhesivos Relyx Ultimate (RU) y CHOICETM 2 (CH) en restauraciones indirectas de porcelana feldespática reforzada con disilicato de litio. Materiales y método: Se trabajo sobre una muestra de 60 bloques de porcelana reforzada con disilicato de litio IPS e.max de 5mm3 , se incluyeron en bloques de acrílico y se dividieron en dos grupos; Grupo I: 30 bloques con cemento RU y Grupo II: 30 bloques con cemento CH. Se preparó cada cemento y luego fotopolimerizó, según indicaciones del fabricante. Se realizó un metodo de envejecimiento por 24 horas y, finalmente, la prueba de resistencia al microcizallamiento con la máquina Shear Bond Tester. Los resultados se tabularon en una planilla y los valores de resistencia adhesiva se analizaron estadísticamente con técnicas no paramétricas (test estadísticos de prueba: U de Mann-Whitney). Resultados: el grupo de RU obtuvo un valor medio de 10,66 ± 4,18 MPa, mientras que el grupo de CH obtuvo un valor medio superior de 15,28 ± 4,70 MPa. El análisis estadístico revela que existe diferencia significativa en la cementación con RU y CH (valor p<0.05). Conclusiones: Existe una diferencia estadísticamente significativa entre los cementos utilizados, en donde el cemento CH presentó una resistencia adhesiva mayor que el cemento RU.Obtaining a higher and longer adhesive strength in indirect ceramic restorations is a prerequisite for clinical success. There is a wide variety of dental cements and it is necessary to compare and study their properties. Aim: To evaluate the adhesive resistance to micro shear bond strength between Relyx Ultimate (UK) and CHOICETM 2 (CH) adhesive cements in indirect restorations of feldspathic porcelain reinforced with lithium disilicate. Materials and method: We worked on a sample of 60 blocks of porcelain reinforced with IPS e.max lithium disilicate of 5 mm3 , this were included in acrylic blocks and were divided into two groups; Group I: 30 blocks with RU cement and Group II: 30 blocks with CH cement. Each cement was prepared and then light-cured, according to the manufacturer's instructions. An aging method was carried out for 24 hours and, finally, the micro shear bond strength resistance test with the Shear Bond Tester machine. The results were tabulated in a spreadsheet and the values of adhesive strength were analyzed statistically with non-parametric techniques (test statistical tests: Mann-Whitney U). Results: the RU group obtained a mean value of 10.66 ± 4.18 MPa, while the CH group obtained a higher average value of 15.28 ± 4.70 MPa. The statistical analysis reveals that there is a significant difference in cementation with RU and CH (p value <0.05). Conclusions: There is a statistically significant difference between the cements used, where the CH cement had a higher adhesive strength than the RU cement

VIS-NIR, SWIR and LWIR Imagery for Estimation of Ground Bearing Capacity

Ground bearing capacity has become a relevant concept for site-specific management that aims to protect soil from the compaction and the rutting produced by the indiscriminate use of agricultural and forestry machines. Nevertheless, commonly known techniques for its estimation are cumbersome and time-consuming. In order to alleviate these difficulties, this paper introduces an innovative sensory system based on Visible-Near InfraRed (VIS-NIR), Short-Wave InfraRed (SWIR) and Long-Wave InfraRed (LWIR) imagery and a sequential algorithm that combines a registration procedure, a multi-class SVM classifier, a K-means clustering and a linear regression for estimating the ground bearing capacity. To evaluate the feasibility and capabilities of the presented approach, several experimental tests were carried out in a sandy-loam terrain. The proposed solution offers notable benefits such as its non-invasiveness to the soil, its spatial coverage without the need for exhaustive manual measurements and its real time operation. Therefore, it can be very useful in decision making processes that tend to reduce ground damage during agricultural and forestry operations.The authors acknowledge funding from the European commission in the 7th Framework Programme (CROPS Grant Agreement No. 246252) and partial funding under ROBOCITY2030-III-CM project (Robótica aplicada a la mejora de la calidad de vida de los ciudadanos. Fase III; S2013/MIT-2748), funded by Programa de Actividades I + D en la Comunidad de Madrid and cofunded by Structural Funds of the EU. Héctor Montes also acknowledges support from Universidad Tecnológica de Panamá.We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).CHF 1,620 APC fee funded by the EC FP7 Post-Grant Open Access PilotPeer reviewe

IceCube3--a new window on the Universe

This paper gives an overview of the scientific goals of IceCube with an emphasis on the importance of atmospheric neutrinos. Status and schedule for completing the detector are presented.Comment: 13 pages, 6 figures, to appear in A.I.P. Conf. Proceedings, 3rd Latin American School on Cosmic Rays, Arequipa, Peru, September, 200

Limitaciones de los estudios por imágenes en pacientes con atresia de vía biliar y su relación con citomegalovirus

La atresia de vías biliares es una patología obstructiva que cursa con fibrosis y obliteración progresiva de las vías biliares extrahepáticas y como consecuencia lesión del parénquima hepático y de las vías biliares intrahepáticas. Como evolución natural, puede progresar a cirrosis hepática temprana y finalmente el fallecimiento de los pacientes antes de los 3 años (1). Es la causa más común de colestasis en la infancia temprana e indicación más frecuente de trasplante hepático en niños. El diagnóstico precoz, seguido de tratamiento quirúrgico en las primeras semanas de vida mejora sustancialmente el pronóstico de la enfermedad. Con este caso describimos las limitaciones que presentan los estudios por imágenes ante un caso de atresia de vías biliares asociado a infección por citomegalovirus.&nbsp

Design of a training tool for improving the use of hand-held detectors in humanitarian demining

Purpose - The purpose of this paper is to introduce the design of a training tool intended to improve deminers' technique during close-in detection tasks. Design/methodology/approach - Following an introduction that highlights the impact of mines and improvised explosive devices (IEDs), and the importance of training for enhancing the safety and the efficiency of the deminers, this paper considers the utilization of a sensory tracking system to study the skill of the hand-held detector expert operators. With the compiled information, some critical performance variables can be extracted, assessed, and quantified, so that they can be used afterwards as reference values for the training task. In a second stage, the sensory tracking system is used for analysing the trainee skills. The experimentation phase aims to test the effectiveness of the elements that compose the sensory system to track the hand-held detector during the training sessions. Findings - The proposed training tool will be able to evaluate the deminers' efficiency during the scanning tasks and will provide important information for improving their competences. Originality/value - This paper highlights the need of introducing emerging technologies for enhancing the current training techniques for deminers and proposes a sensory tracking system that can be successfully utilised for evaluating trainees' performance with hand-held detectors. © Emerald Group Publishing Limited.The authors acknowledge funding from the European Community's Seventh Framework Programme (FP7/2007‐2013 TIRAMISU) under Grant Agreement No. 284747 and partial funding under Robocity2030 S‐0505/DPI‐0176 and FORTUNA A1/039883/11 (Agencia Española de Cooperación Internacional para el Desarrollo – AECID). Dr Roemi Fernández acknowledges support from CSIC under grant JAE‐DOC. Dr Héctor Montes acknowledges support from Universidad Tecnológica de Panamá and from CSIC under grant JAE‐DOC.Peer Reviewe

Comparative Genomics Analysis of a New Exiguobacterium Strain from Salar de Huasco Reveals a Repertoire of Stress-Related Genes and Arsenic Resistance

Indexación: Web of Science; Scopus.The Atacama Desert hosts diverse ecosystems including salt flats and shallow Andean lakes. Several heavy metals are found in the Atacama Desert, and microorganisms growing in this environment show varying levels of resistance/tolerance to copper, tellurium, and arsenic, among others. Herein, we report the genome sequence and comparative genomic analysis of a new Exiguobacterium strain, sp. SH31, isolated from an altiplanic shallow athalassohaline lake. Exiguobacterium sp. SH31 belongs to the phylogenetic Group II and its closest relative is Exiguobacterium sp. S17, isolated from the Argentinian Altiplano (95% average nucleotide identity). Strain SH31 encodes a wide repertoire of proteins required for cadmium, copper, mercury, tellurium, chromium, and arsenic resistance. Of the 34 Exiguobacterium genomes that were inspected, only isolates SH31 and S17 encode the arsenic efflux pump Acr3. Strain SH31 was able to grow in up to 10 mM arsenite and 100 mM arsenate, indicating that it is arsenic resistant. Further, expression of the ars operon and acr3 was strongly induced in response to both toxics, suggesting that the arsenic efflux pump Acr3 mediates arsenic resistance in Exiguobacterium sp. SH31.http://journal.frontiersin.org/article/10.3389/fmicb.2017.00456/ful

A model for the electromagnetic spectrum of the inner jets of Cen A

Centaurus A, the closest active galaxy, has been detected from radio to high-energy gamma-rays. The synchrotron radiation by extremely high energy protons may be a suitable mechanism to explain the MeV to GeV emission detected by the instruments of the Compton Gamma-Ray Observatory, as coming from the inner jets. This scenario requires a relatively large magnetic field of about 10^4 G that could be present only close to the central black hole. We investigate the spectral energy distribution (SED) resulting from a one-zone compact acceleration region, where both leptonic and hadronic relativistic populations arise. We present here results of such a model, where we have considered synchrotron radiation by primary electrons and protons, inverse Compton interactions, and gamma-ray emission originated by the inelastic hadronic interactions between relativistic protons and cold nuclei within the jets themselves. Photo-meson production by relativistic hadrons were also taken into account, as well as the effects of secondary particles injected by all interactions. The internal and external absorption of gamma rays is shown to be of great relevance to shape the observable SED, which was also recently constrained by the results of HESS.Comment: 13 pages (ref. style), submitted to MNRAS on December 04, 2008. Waiting for revie

El teatro de la Universidad de Concepción durante la Unidad Popular (UP) en Chile 1970 -1973. Democracia y política

This research was specifically focused on the theatre of Universidad deConcepción during the Popular Unit period (1970-1973). The objective was toanalyze social imaginaries of democracy and scenic art present in this artisticgroup of southern Chile. By applying deep interviews to key actors, as aninstrument to collect data, and through a qualitative analysis with the ATLAS/TI Show, it was possible to establish that social imaginary of art and democracywere part of a political project where art was part of the regeneration proposedby the left-wing politics of that period.La presente investigación centró su preocupación en el teatro de la Universidadde Concepción durante el período de la Unidad Popular (1970 - 1973). Tuvocomo objetivo analizar los imaginarios sociales de la democracia y del arteescénico, presentes en esta agrupación artística del sur de Chile. Mediante laaplicación de entrevistas en profundidad a actores clave, como instrumentode recogida de datos, y posteriormente, mediante un análisis cualitativo conel programa ATLAS/TI, se logró establecer que el imaginario social del arte yla democracia formó parte de un proyecto político donde el arte constituíaparte de la regeneración propuesta por la izquierda de la época

Optimización económica y técnica mediante la implementación de losas prefabricadas en el edificio Sente

The present research sets out the economic and technical evaluation of two construction systems used in the actual industry, and includes the comparison of cost, time lapse of the slabs construction and the level of construction solid waste. The analyzed systems were: i) Precast beams and ii) Precast slabs, evaluated in Sente Building. In addition, the criteria of technological level is presented which support the reduction in execution time achieved by the precast slabs system in comparison with the precast beam system. As a part of the economic evaluation, the costs associated with every constructive procedure and execution period were estimated. The results showed that, in comparison with precast beams system, the precast slabs system achieved a reduction of the cost building cost in 3.45%, a reduction in time execution of 10% accumulated in both building towers, and ultimately, the precast slab system reduces the quantity of solid waste of construction as requires 18.5% minus of in-situ concrete.Esta investigación consiste en la evaluación económica y técnica de dos sistemas de construcción utilizados en la industria. Se realizó la comparación del costo, duración de la fase del casco y nivel de residuos de construcción por sistema. Los sistemas analizados son: i) Viguetas prefabricadas y ii) Prelosas prefabricadas, aplicado en el edificio multifamiliar Sente. Además, se presenta el criterio del nivel tecnológico, que muestra la reducción del plazo con el sistema de prelosas, en comparación con el de viguetas. Como parte de la evaluación económica se estimaron los costos que implica cada sistema, acorde a su secuencia constructiva y periodos de ejecución. El resultado fue que el sistema de prelosas, en comparación al de viguetas,  logra reducir el costo de obra en 3.4%, el plazo del casco en 10% (acumulado entre ambas torres). También este sistema disminuye la generación de residuos sólidos de construcción, porque requiere 18.5% menos de concreto in situ en obra, que el de viguetas prefabricadas