Dynamical Compactification and Inflation in Einstein-Yang-Mills Theory with Higher Derivative Coupling

We study cosmology of the Einstein-Yang-Mills theory in ten dimensions with a quartic term in the Yang-Mills field strength. We obtain analytically a class of cosmological solutions in which the extra dimensions are static and the scale factor of the four-dimensional Friedmann-Lemaitre-Robertson-Walker metric is an exponential function of time. This means that the model can explain inflation. Then we look for solutions that describe dynamical compactification of the extra dimensions. The effective cosmological constant $\lambda_1$ in the four-dimensional universe is determined from the gravitational coupling, ten-dimensional cosmological constant, gauge coupling and higher derivative coupling. By numerical integration, the solution with $\lambda_1=0$ is found to behave as a matter-dominated universe which asymptotically approaches flat space-time, while the solution with a non-vanishing $\lambda_1$ approaches de Sitter space-time in the asymptotic future.Comment: 30 pages, 7 figure

ECOSSE: Estimating Carbon in Organic Soils - Sequestration and Emissions: Final Report

Background Climate change, caused by greenhouse gas ( GHG) emissions, is one of the most serious threats facing our planet, and is of concern at both UK and devolved administration levels. Accurate predictions for the effects of changes in climate and land use on GHG emissions are vital for informing land use policy. Models which are currently used to predict differences in soil carbon (C) and nitrogen (N) caused by these changes, have been derived from those based on mineral soils or deep peat. None of these models is entirely satisfactory for describing what happens to organic soils following land-use change. Reports of Scottish GHG emissions have revealed that approximately 15% of Scotland's total emissions come from land use changes on Scotland's high carbon soils; the figure is much lower for Wales. It is therefore important to reduce the major uncertainty in assessing the carbon store and flux from land use change on organic soils, especially those which are too shallow to be deep peats but still contain a large reserve of C. In order to predict the response of organic soils to external change we need to develop a model that reflects more accurately the conditions of these soils. The development of a model for organic soils will help to provide more accurate values of net change to soil C and N in response to changes in land use and climate and may be used to inform reporting to UKGHG inventories. Whilst a few models have been developed to describe deep peat formation and turnover, none have so far been developed suitable for examining the impacts of land-use and climate change on the types of organic soils often subject to land-use change in Scotland and Wales. Organic soils subject to land-use change are often (but not exclusively) characterised by a shallower organic horizon than deep peats (e.g. organo-mineral soils such as peaty podzols and peaty gleys). The main aim of the model developed in this project was to simulate the impacts of land-use and climate change in these types of soils. The model is, a) be driven by commonly available meteorological data and soil descriptions, b) able to simulate and predict C and N turnover in organic soils, c) able to predict the impacts of land-use change and climate change on C and N stores in organic soils in Scotland and Wales. In addition to developing the model, we have undertaken a number of other modelling exercises, literature searches, desk studies, data base exercises, and experimentation to answer a range of other questions associated with the responses of organic soils in Scotland and Wales to climate and land-use change. Aims of the ECOSSE project The aims of the study were: To develop a new model of C and N dynamics that reflects conditions in organic soils in Scotland and Wales and predicts their likely responses to external factors To identify the extent of soils that can be considered organic in Scotland and Wales and provide an estimate of the carbon contained within them To predict the contribution of CO 2, nitrous oxide and methane emissions from organic soils in Scotland and Wales, and provide advice on how changes in land use and climate will affect the C and N balance In order to fulfil these aims, the project was broken down into modules based on these objectives and the report uses that structure. The first aim is covered by module 2, the second aim by module 1, and the third aim by modules 3 to 8. Many of the modules are inter-linked. Objectives of the ECOSSE project The main objectives of the project were to: Describe the distribution of organic soils in Scotland and Wales and provide an estimate of the C contained in them Develop a model to simulate C and N cycling in organic soils and provide predictions as to how they will respond to land-use, management and climate change using elements of existing peat, mineral and forest soil models Provide predictive statements on the effects of land-use and climate change on organic soils and the relationships to GHG emissions, including CO 2, nitrous oxide and methane. Provide predictions on the effects of land use change and climate change on the release of Dissolved Organic Matter from organic soils Provide estimates of C loss from scenarios of accelerated erosion of organic soils Suggest best options for mitigating C and N loss from organic soils Provide guidelines on the likely effects of changing land-use from grazing or semi-natural vegetation to forestry on C and N in organic soils Use the land-use change data derived from the Countryside Surveys of Scotland and Wales to provide predictive estimates for changes to C and N balance in organic soils over time

Pharmacokinetics of butorphanol following intravenous and intramuscular administration in donkeys: A preliminary study

The pharmacokinetics of butorphanol after intravenous (IVB) and intramuscular (IMB) administration in donkeys were determined in this preliminary study. Healthy male gelded donkeys (n = 5), aged 6–12 years old, were administered 0.1 mg/kg butorphanol IV or IM in a randomized, crossover design. Blood samples were obtained at predetermined intervals for 24 h (IVB) and 48 h (IMB) after administration. Plasma butorphanol concentrations were determined by high performance liquid chromatography and pharmacokinetic parameters were calculated. Following IVB administration, mean (± SE) apparent volume of distribution, elimination half-life, total body clearance, and area under the plasma concentration time curve from time 0 to infinity (AUC0−∞) were 322 ± 50 mL/kg, 0.83 ± 0.318 h, 400 ± 114 mL/h/kg, 370 ± 131 h·ng/mL, respectively. After IMB administration, a maximum plasma drug concentration of 369 ± 190 ng/mL was reached at 0.48 ± 0.09 h. The IMB AUC0−∞ was 410 ± 60 h·ng/mL. Bioavailability of IMB was 133 ± 45%. The pharmacokinetics of butorphanol in healthy donkeys was characterized by faster elimination half-life compared to values from the equine literature

Calcinación de huesos: análisis de cambios de color con fines forenses

Introducción: Los cambios morfológicos que experimentan los huesos sometidos a elevadas temperaturas presentan un reto para los laboratorios forenses y antropológicos. El cambio producido en ellos puede verse influenciado por la temperatura y tiempo de exposición al calor. Objetivo: correlacionar cambios del color en el hueso con la temperatura de incineración. Material y métodos. Un total de 32 huesos largos de 5 centímetros de longitud fueron calcinados en un horno de mufla. Ocho de ellos fueron sometidos a 200 °C: 4 durante 30 minutos y otros 4 durante 60 minutos. Otros 8 se expusieron a 400 °C: 4 durante 30 minutos y los otros 4 durante 60 minutos. Ocho más se sometieron a 600 °C: 4 durante 30 minutos y 4 durante 60 minutos. Los 8 restantes se sometieron a 800 °C e igualmente divididos en un grupo de 4 sometido durante un tiempo de 30 minutos y otros 4 durante 60 minutos Además, 4 se utilizaron como control. Con ayuda de lupas y fotografías se realizó un examen visual donde se describió el color de la cortical y medula del hueso. También, se midió el cambio de color con un espectrofotómetro portátil. Finalmente se realizó estudio de correlación entre los cambios de color y la exposición a la temperatura y tiempos. Resultados. Los huesos sometidos a 200 ºC mostraron un color marrón mientras que a 400 el color fue negro en el 100% de casos. A 600 y 800 ºC viraban a gris y blanco con tonos azulados. Los resultados mostraron alteraciones del color significativas en los valores de Blanqueamiento (WI) y Crominancia (y). Además, se observa correlación significativa entre el color y la temperatura tanto en los huesos sometidos durante 30 como a 60 minutos en los mismos parámetros anteriores. . Conclusión. De acuerdo con estos resultados, el análisis colorimétrico de los huesos incinerados puede ayudar a estimar la temperatura de exposición siendo la temperatura el factor más influyente.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Calcinación de dientes y huesos: estudio morfológico con fines forenses

INTRODUCCIÓN: Los cambios físicos y morfológicos (macro y microscópicos) que experimentan los dientes y huesos sometidos a altas temperaturas han sido motivo de nuestros estudios en los últimos años. El cambio producido en ellos pueden verse influenciados por una serie de factores externos como la temperatura y el tiempo en el que han permanecido expuestos. Por ello, el objetivo de este estudio es conocer los cambios morfológicos que se originan en la calcinación de dientes y huesos a diferentes temperaturas. MATERIAL Y MÉTODOS: Diez muestras mineralizadas (4 dientes y 6 huesos largos) divididas en dos grupos se someten a 200 y 400 ºC durante 30 minutos en un horno de mufla (Nabertherm LT 40/12, Nabertherm GmbH, Germany). Posteriormente, se observaron mediante un Microscopio Multizoom Nikon modelo AZ 100 con objetivo 2 y zoom 1 asociado a un a un ordenador (PC) donde está instalado el programa Nis-Elements diseñado para la captación, almacenaje y tratamiento de fotografías. RESULTADOS: Las fisuras longitudinales se inician en el 100% de los dientes sometidos a 200 ºC durante 30 minutos tanto a nivel coronal como radicular. A esta misma temperatura y tiempo no se observa fisuras en los huesos largos. A 400 ºC se originan fracturas “en casquete” del esmalte en el molar y fractura radicular y coronal en el premolar. Además, se inician las fisuras a nivel medular de los huesos. CONCLUSIONES: Según este estudio, ante la misma temperatura y tiempo de calcinación los dientes se fisuran y fracturan antes que los huesos largos.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

The optical counterpart to the peculiar X-ray transient XTE J1739-302

The weak X-ray transient XTE J1739-302, characterized by extremely short outbursts, has recently been identified with a reddened star. Here we present spectroscopy and photometry of the counterpart, identifying it as a O8Iab(f) supergiant at a distance of ~2.3 kpc. XTE J1739-302 becomes thus characterized as the prototype of the new class of Supergiant Fast X-ray Transients. The optical and infrared spectra of the counterpart to XTE J1739-302 do not reveal any obvious characteristics setting it apart from other X-ray binaries with supergiant companions, which display a very different type of X-ray lightcurve.Comment: Accepted for publication in ApJ. Companion paper to Smith et al. (astro-ph/0510658). 5 figures, 9 page

Osteohistological analyses reveal diverse strategies of theropod dinosaur body-size evolution

The independent evolution of gigantism among dinosaurs has been a topic of long-standing interest, but it remains unclear if gigantic theropods, the largest bipeds in the fossil record, all achieved massive sizes in the same manner, or through different strategies. We perform multi-element histological analyses on a phylogenetically broad dataset sampled from eight theropod families, with a focus on gigantic tyrannosaurids and carcharodontosaurids, to reconstruct the growth strategies of these lineages and test if particular bones consistently preserve the most complete growth record. We find that in skeletally mature gigantic theropods, weight-bearing bones consistently preserve extensive growth records, whereas non- weight-bearing bones are remodelled and less useful for growth reconstruction, contrary to the pattern observed in smaller theropods and some other dinosaur clades. We find a heterochronic pattern of growth fitting an acceleration model in tyrannosaurids, with allosauroid carcharodontosaurids better fitting a model of hypermorphosis. These divergent growth patterns appear phylogenetically constrained, representing extreme versions of the growth patterns present in smaller coelurosaurs and allosauroids, respectively. This provides the first evidence of a lack of strong mechanistic or physiological constraints on size evolution in the largest bipeds in the fossil record and evidence of one of the longest-living individual dinosaurs ever documented.Fil: Cullen, Thomas. Field Museum of National History; Estados Unidos. North Carolina State University; Estados Unidos. North Carolina Museum of Natural Sciences; Estados UnidosFil: Canale, Juan Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Confluencia; Argentina. Provincia del Neuquén. Municipalidad de Villa El Chocón. Museo Paleontológico "Ernesto Bachmann"; ArgentinaFil: Apesteguía, Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Confluencia; Argentina. Fundación de Historia Natural Félix de Azara; Argentina. Universidad Maimónides. Área de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y de Diagnóstico; ArgentinaFil: Smith, Nathan D.. Natural History Museum of Los Angeles County. Dinosaur Institute; Estados UnidosFil: Hu, Dongyu. Shenyang Normal University; República de China. Ministry of Natural Resources; República de ChinaFil: Makovicky, Peter J.. Field Museum of National History; Estados Unidos. University of Minnesota; Estados Unido

Building Cooperative Networks

We study the cooperation problem in the framework of evolutionary game theory using the prisoner's dilemma as metaphor of the problem. Considering the growing process of the system and individuals with imitation capacity, we show conditions that allow to form highly cooperative networks of any size and topology. Introducing general considerations of real systems, we reduce the required conditions for cooperation to evolve approaching the benefit-cost ratio r to the theoretical minimum r=1, when the mean connectivity of the individuals is increased. Through the paper, we distinguish different mechanisms that allow the system to maintain high levels of cooperation when the system grows by incorporation of defectors. These mechanisms require heterogeneity among individuals for cooperation to evolve. However, the required conditions and heterogeneities are drastically reduced as compared to those required for static networks.Comment: 24 pages, 8 figure