Variable-stiffness composite panels: Defect tolerance under in-plane tensile loading

Automated Fiber Placement is being extensively used in the production of major composite components for the aircraft industry. This technology enables the production of tow-steered panels, which have been proven to greatly improve the structural efficiency of composites by means of in-plane stiffness variation and load redistribution. However, traditional straight-fiber architectures are still preferred. One of the reasons behind this is related to the uncertainties, as a result of process-induced defects, in the mechanical performance of the laminates. This experimental work investigates the effect of the fiber angle discontinuities between different tow courses in a ply on the un-notched and open-hole tensile strength of the laminate. The influence of several manufacturing parameters are studied in detail. The results reveal that 'ply staggering' and '0% gap coverage' is an effective combination in reducing the influence of defects in these laminates

Circulating progenitor cells during exercise, muscle electro-stimulation and intermittent hypobaric hypoxia in patients with traumatic brain injury. A pilot study

BACKGROUND: Circulating progenitor cells (CPC) treatments may have great potential for the recovery of neurons and brain function. OBJECTIVE: To increase and maintain CPC with a program of exercise, muscle electro-stimulation (ME) and/or intermittent-hypobaric-hypoxia (IHH), and also to study the possible improvement in physical or psychological functioning of participants with Traumatic Brain Injury (TBI). METHODS: Twenty-one participants. Four groups: exercise and ME group (EEG), cycling group (CyG), IHH and ME group (HEG) and control group (CG). Psychological and physical stress tests were carried out. CPC were measured in blood several times during the protocol. RESULTS: Psychological tests did not change. In the physical stress tests the VO2 uptake increased in the EEG and the CyG, and the maximal tolerated workload increased in the HEG. CPC levels increased in the last three weeks in EEG, but not in CyG, CG and HEG. CONCLUSIONS: CPC levels increased in the last three weeks of the EEG program, but not in the other groups and we did not detect performed psychological test changes in any group. The detected aerobic capacity or workload improvement must be beneficial for the patients who have suffered TBI, but exercise type and the mechanisms involved are not clear.

La avenida de la cuenca del Segre (noviembre'83) como experiencia geoambiental

Se pasa revista a los efectos geoambientales producidos por las avenidas denoviembre de 1982 y se intenta una tipología e inventario de impactos así como una cartografía de clasificación de comportamiento de las áreas que fueron cubiertas por las aguas

Radio continuum and near-ingrared study of the MGRO J2019+37 region

Context. MGRO J2019+37 is an unidentified extended source of very high energy gamma-rays originally reported by the Milagro Collaboration as the brightest TeV source in the Cygnus region. Its extended emission could be powered by either a single or several sources. The GeV pulsar AGL J2020.5+3653, discovered by AGILE and associated with PSR J2021+3651, could contribute to the emission from MGRO J2019+37. Our aim is to identify radio and near-infrared sources in the field of the extended TeV source MGRO J2019+37, and study potential counterparts to explain its emission. Methods: We surveyed a region of about 6 square degrees with the Giant Metrewave Radio Telescope (GMRT) at the frequency 610 MHz. We also observed the central square degree of this survey in the near-infrared Ks-band using the 3.5 m telescope in Calar Alto. Archival X-ray observations of some specific fields are included. VLBI observations of an interesting radio source were performed. We explored possible scenarios to produce the multi-TeV emission from MGRO J2019+37 and studied which of the sources could be the main particle accelerator. Results: We present a catalogue of 362 radio sources detected with the GMRT in the field of MGRO J2019+37, and the results of a cross-correlation of this catalog with one obtained at near-infrared wavelengths, which contains ∼3 × 105 sources, as well as with available X-ray observations of the region. Some peculiar sources inside the ∼1◦ uncertainty region of the TeV emission from MGRO J2019+37 are discussed in detail, including the pulsar PSR J2021+3651 and its pulsar wind nebula PWN G75.2+0.1, two new radio-jet sources, the Hii region Sh 2-104 containing two star clusters, and the radio source NVSS J202032+363158. We also find that the hadronic scenario is the most likely in case of a single accelerator, and discuss the possible contribution from the sources mentioned above. Conclusions: Although the radio and GeV pulsar PSR J2021+3651 / AGL J2020.5+3653 and its associated pulsar wind nebula PWN G75.2+0.1 can contribute to the emission from MGRO J2019+37, extrapolation of the GeV spectrum does not explain the detected multi-TeV flux. Other sources discussed here could contribute to the emission of the Milagro source

Práctica educativa y adquisición de la lengua de la escuela

El trabajo que presentamos pretende establecer e implamentar criterios respecto la organización escolar y la práctica educativa para mejorar las competencias básicas del alumnado extranjero que participa en las aulas de Cataluña con una gran diversidad respecto el conocimiento de la lengua de la escuela. En concreto, buscamos profundizar y localizar los factores y elementos relevantes para la organización escolar y la práctica educativa en escuelas plurilingües con estas características

Hexadom : El dòmino hexagonal

L'Hexadom és un joc de taula, de creació pròpia, inspirat en el dòmino tradicional, amb el que hi comparteix l'objectiu: jugar totes les fitxes (o hexàgons en el cas de l'Hexadom). Però hi ha una diferència substancial: la seva complexitat; ja que a diferència del joc original -on s'uneixen els extrems de dues fitxes que tinguin el mateix número- a l'Hexadom s'han d'unir hexàgons entre si, com a mínim per dos dels seus costats, mantenint la coherència entre els colors.

Present and future methodology for the implementation of decision support systems for traffic management

Real-time predictions are an indispensable requirement for traffic management in order to be able to evaluate the effects of different available strategies or policies. The combination of predicting the state of the network and the evaluation of different traffic management strategies in the short term future allows system managers to anticipate the effects of traffic control strategies ahead of time in order to mitigate the effect of congestion. This paper presents the current framework of decision support systems for traffic management based on short and medium-term predictions and includes some reflections on their likely evolution, based on current scientific research and the evolution of the availability of new types of data and their associated methodologies.

Planimetria arqueològica de Tarraco

Aquesta obra és fruit d’un treball de documentació i digitalització de les fonts bibliogràfiques i administratives de les excavacions i troballes arqueològiques dutes a terme a la ciutat de Tarragona des del segle XIX fins al desembre del 2004. La informació arqueològica recollida prové dels treballs que han efectuat 61 arqueòlegs i s’ha comptat amb la col·laboració de les empreses d’arqueologia que treballen a la ciutat i el suport de la Reial Societat Arqueològica Tarraconense. La important activitat arqueològica duta a terme a Tarragona, especialment en les darreres dècades del segle XX, feia necessària una compilació en una planimetria arqueològica dels nombrosos vestigis conservats o documentats. Calia recollir tota la informació per posar-la a l’abast de tots els agents que intervenen en el tractament del patrimoni arqueològic, tant des del camp de la recerca estricta com des del de la gestió arqueològica pròpiament, de l’urbanisme i de la difusió i projecció d’aquest passat.

Design concepts for the Cherenkov Telescope Array CTA: an advanced facility for ground-based high-energy gamma-ray astronomy

Ground-based gamma-ray astronomy has had a major breakthrough with the impressive results obtained using systems of imaging atmospheric Cherenkov telescopes. Ground-based gamma-ray astronomy has a huge potential in astrophysics, particle physics and cosmology. CTA is an international initiative to build the next generation instrument, with a factor of 5-10 improvement in sensitivity in the 100 GeV-10 TeV range and the extension to energies well below 100 GeV and above 100 TeV. CTA will consist of two arrays (one in the north, one in the south) for full sky coverage and will be operated as open observatory. The design of CTA is based on currently available technology. This document reports on the status and presents the major design concepts of CTA.

Design concepts for the Cherenkov Telescope Array CTA: an advanced facility for ground-based high-energy gamma-ray astronomy

Ground-based gamma-ray astronomy has had a major breakthrough with the impressive results obtained using systems of imaging atmospheric Cherenkov telescopes. Ground-based gamma-ray astronomy has a huge potential in astrophysics, particle physics and cosmology. CTA is an international initiative to build the next generation instrument, with a factor of 5-10 improvement in sensitivity in the 100 GeV-10 TeV range and the extension to energies well below 100 GeV and above 100 TeV. CTA will consist of two arrays (one in the north, one in the south) for full sky coverage and will be operated as open observatory. The design of CTA is based on currently available technology. This document reports on the status and presents the major design concepts of CTA.

Design concepts for the Cherenkov Telescope Array CTA: an advanced facility for ground-based high-energy gamma-ray astronomy

Ground-based gamma-ray astronomy has had a major breakthrough with the impressive results obtained using systems of imaging atmospheric Cherenkov telescopes. Ground-based gamma-ray astronomy has a huge potential in astrophysics, particle physics and cosmology. CTA is an international initiative to build the next generation instrument, with a factor of 5-10 improvement in sensitivity in the 100 GeV-10 TeV range and the extension to energies well below 100 GeV and above 100 TeV. CTA will consist of two arrays (one in the north, one in the south) for full sky coverage and will be operated as open observatory. The design of CTA is based on currently available technology. This document reports on the status and presents the major design concepts of CTA.

Efectos de la aplicación de biosólidos en plantaciones de especies leñosas para restauración de canteras de caliza mediterráneas

Los programas de restauración de las canteras de caliza situadas en el macizo del Garraf (sudoeste de la cordillera Litoral catalana) contemplan la plantación de especies leñosas autóctonas como medida para mitigar el impacto visual y para optimizar la restauración ecológica tras la explotación del recurso mineral. Las condiciones ambientales de partida poco favorables (elevadas pendientes y substratos poco fértiles) pueden ser limitantes para la instalación y evolución de leñosas, de forma que la adición de compost puede ser una vía para mejorar su rendimiento. En este trabajo evaluamos el efecto de la aplicación extensiva de compost en plantaciones de cuatro especies de árboles y arbustos de un año de edad en parcelas sembradas con distintas mezclas de herbáceas. Como resultado principal se observó que en las parcelas con compost la supervivencia de Pinus halepensis y Rhamnus alaternus fue menor, aunque el crecimiento de las cuatro especies ensayadas fue superior. Las leñosas presentaron una supervivencia superior en las parcelas sembradas con herbáceas autóctonas, que habían desarrollado menor cobertura, respecto a las siembras con herbáceas comerciales, con mayor cubierta.

Another Look at the Null of Stationary Real Exchange Rates: Panel Data with Structural Breaks and Cross-section Dependence

This paper re-examines the null of stationary of real exchange rate for a panel of seventeen OECD developed countries during the post-Bretton Woods era. Our analysis simultaneously considers both the presence of cross-section dependence and multiple structural breaks that have not received much attention in previous panel methods of long-run PPP. Empirical results indicate that there is little evidence in favor of PPP hypothesis when the analysis does not account for structural breaks. This conclusion is reversed when structural breaks are considered in computation of the panel statistics. We also compute point estimates of half-life separately for idiosyncratic and common factor components and find that it is always below one year.

Panel Data Stochastic Convergence Analysis of the Mexican Regions

The stochastic convergence amongst Mexican Federal entities is analyzed in panel data framework. The joint consideration of cross-section dependence and multiple structural breaks is required to ensure that the statistical inference is based on statistics with good statistical properties. Once these features are accounted for, evidence in favour of stochastic convergence is found. Since stochastic convergence is a necessary, yet insufficient condition for convergence as predicted by economic growth models, the paper also investigates whether-convergence process has taken place. We found that the Mexican states have followed either heterogeneous convergence patterns or divergence process throughout the analyzed period.