Fractional Order Description of DNA

This study addresses the deoxyribonucleic acid (DNA) and proposes a procedure based on the association of statistics, information theory, signal processing, Fourier analysis and fractional calculus for describing fundamental characteristics of the DNA. In a first phase the 24 chromosomes of the Human are evaluated. In a second phase, 10 chromosomes for different species are also processed and the results compared. The results reveal invariance in the description and close resemblances with fractional Brownian motion.

Modeling Vegetable Fractals by means of Fractional-order Equations

This paper characterizes four ‘fractal vegetables’: (i) cauliflower (brassica oleracea var. Botrytis); (ii) broccoli (brassica oleracea var. italica); (iii) round cabbage (brassica oleracea var. capitata) and (iv) Brussels sprout (brassica oleracea var. gemmifera), by means of electrical impedance spectroscopy and fractional calculus tools. Experimental data is approximated using fractional-order models and the corresponding parameters are determined with a genetic algorithm. The Havriliak-Negami five-parameter model fits well into the data, demonstrating that classical formulae can constitute simple and reliable models to characterize biological structures.

Fractional Dynamics in Forest Fires

Every year forest fires consume large areas, being a major concern in many countries like Australia, United States and Mediterranean Basin European Countries (e.g., Portugal, Spain, Italy and Greece). Understanding patterns of such events, in terms of size and spatiotemporal distributions, may help to take measures beforehand in view of possible hazards and decide strategies of fire prevention, detection and suppression. Traditional statistical tools have been used to study forest fires. Nevertheless, those tools might not be able to capture the main features of fires complex dynamics and to model fire behaviour [1]. Forest fires size-frequency distributions unveil long range correlations and long memory characteristics, which are typical of fractional order systems [2]. Those complex correlations are characterized by self-similarity and absence of characteristic length-scale, meaning that forest fires exhibit power-law (PL) behaviour. Forest fires have also been proved to exhibit time-clustering phenomena, with timescales of the order of few days [3]. In this paper, we study forest fires in the perspective of dynamical systems and fractional calculus (FC). Public domain forest fires catalogues, containing data of events occurred in Portugal, in the period 1980 up to 2011, are considered. The data is analysed in an annual basis, modelling the occurrences as sequences of Dirac impulses. The frequency spectra of such signals are determined using Fourier transforms, and approximated through PL trendlines. The PL parameters are then used to unveil the fractional-order dynamics characteristics of the data. To complement the analysis, correlation indices are used to compare and find possible relationships among the data. It is shown that the used approach can be useful to expose hidden patterns not captured by traditional tools.

Foresight exercises as a tool for decision-making: the example of two case studies in health

Based on the report for the unit “Foresight Methods Analysis” of the PhD programme on Technology Assessment at the Universidade Nova de Lisboa, under the supervision of Prof. Dr. António B. Moniz

Multibody systems formulation

"Series: Solid mechanics and its applications, vol. 226"

Inflammation-induced alteration of astrocyte mitochondrial dynamics requires autophagy for mitochondrial network maintenance.

Accumulating evidence suggests that changes in the metabolic signature of astrocytes underlie their response to neuroinflammation, but how proinflammatory stimuli induce these changes is poorly understood. By monitoring astrocytes following acute cortical injury, we identified a differential and region-specific remodeling of their mitochondrial network: while astrocytes within the penumbra of the lesion undergo mitochondrial elongation, those located in the core-the area invaded by proinflammatory cells-experience transient mitochondrial fragmentation. In brain slices, proinflammatory stimuli reproduced localized changes in mitochondrial dynamics, favoring fission over fusion. This effect was triggered by Drp1 phosphorylation and ultimately resulted in reduced respiratory capacity. Furthermore, maintenance of the mitochondrial architecture critically depended on the induction of autophagy. Deletion of Atg7, required for autophagosome formation, prevented the reestablishment of tubular mitochondria, leading to marked reactive oxygen species accumulation and cell death. Thus, our data reveal autophagy to be essential for regenerating astrocyte mitochondrial networks during inflammation.

National Alcohol Policy Ireland

The National Alcohol Policy is directed at reducing the prevalence of alcohol-related problems through an emphasis on moderation in alcohol consumption. The importance of a comprehensive alcohol policy was highlighted when Ireland endorsed the European Charter on Alcohol in December 1995 along with 48 other Member States of the WHO European Region. The alcohol-related problems are multidimensional, therefore the solutions most be multi-sectoral. This means that commitment to the National Alcohol Policy must be on the agenda of policy makers in all sectors and at all levels. An Alcohol Policy requires both environmental and individual strategies. There is strong evidence that policies which influence access to alcohol, control pricing through taxation and other public health measures, can have a positive impact on curtailing the health and social burden resulting from drinking (Edwards et al. 1994). However, a key to the effectiveness of such strategies is public support, enforcement and maintenance of the policies. In examining the rationale for a National Alcohol Policy a number of elements have been identified. Research is urgently required to identify attitudes and patterns of alcohol consumption across the population and within sub-groups of the population. Based on sound research, a sensible drinking message of Less is Better should form an educational empowerment programme with regional and local initiatives as a required and integral part of such a campaign. A health education programme in all schools should be part of the core curriculum. The availability and effectiveness of treatment services need to be established. Action to contain the availability of alcohol could be achieved by reducing the number of special exemptions for longer opening hours and controlling access to underage drinking by ID schemes nation-wide. The enforcement of drink driving legislation including random breath testing needs to be continued to reduce alcohol-related traffic accidents. All levels of the Drinks Industry should recognise that people have the right to be safeguarded from pressures to drink. Finally, a National Alcohol Policy could be co-ordinated by a wider National Substance Use Surveillance Unit.This resource was contributed by The National Documentation Centre on Drug Use.

Early detection of idiopathic Parkinson's disease based on magnetic resonance imaging

The diagnosis of idiopathic Parkinson's disease (IPD) is entirely clinical. The fact that neuronal damage begins 5-10 years before occurrence of sub-clinical signs, underlines the importance of preclinical diagnosis. A new approach for in-vivo pathophysiological assessment of IPD-related neurodegeneration was implemented based on recently developed neuroimaging methods. It is based on non- invasive magnetic resonance data sensitive to brain tissue property changes that precede macroscopic atrophy in the early stages of IPD. This research aims to determine the brain tissue property changes induced by neurodegeneration that can be linked to clinical phenotypes which will allow us to create a predictive model for early diagnosis in IPD. We hypothesized that the degree of disease progression in IPD patients will have a differential and specific impact on brain tissue properties used to create a predictive model of motor and non-motor impairment in IPD. We studied the potential of in-vivo quantitative imaging sensitive to neurodegeneration- related brain tissue characteristics to detect changes in patients with IPD. We carried out methodological work within the well established SPM8 framework to estimate the sensitivity of tissue probability maps for automated tissue classification for detection of early IPD. We performed whole-brain multi parameter mapping at high resolution followed by voxel-based morphometric (VBM) analysis and voxel-based quantification (VBQ) comparing healthy subjects to IPD patients. We found a trend demonstrating non-significant tissue property changes in the olfactory bulb area using the MT and R1 parameter with p<0.001. Comparing to the IPD patients, the healthy group presented a bilateral higher MT and R1 intensity in this specific functional region. These results did not correlate with age, severity or duration of disease. We failed to demonstrate any changes with the R2* parameter. We interpreted our findings as demyelination of the olfactory tract, which is clinically represented as anosmia. However, the lack of correlation with duration or severity complicates its implications in the creation of a predictive model of impairment in IPD.

As comunidades imigrantes em Cabo Verde: os chineses em São Vicente e a sua participação no desenvolvimento do comércio

Esta investigação insere-se na temática do Empreendedorismo Imigrante e do Comércio Étnico. Trata-se de uma pesquisa que se debruça sobre a imigração para Cabo Verde, com destaque para a análise da imigração chinesa, sobretudo dedicada ao comércio na ilha de São Vicente. O objectivo geral deste trabalho prende-se com a identificação do contributo da comunidade imigrante supracitada no processo de desenvolvimento de São Vicente, através da instalação e da prática de actividades comerciais. Para concretização deste objectivo foi desenvolvido, durante 5 meses, um trabalho de terreno em Cabo Verde (Santiago e São Vicente). O trabalho empírico socorreu-se de entrevistas formais à presidente da Câmara Municipal de São Vicente e a personalidades da Embaixada de China em Cabo Verde , e informais efectuadas aos comerciantes chineses e seus funcionários, bem como aos comerciantes locais. Foram ainda aplicados inquéritos a todos os comerciantes chineses na ilha de São Vicente, processo que permitiu obter a informação necessária para a caracterização da comunidade chinesa e das actividades comerciais por ela aqui desenvolvidas. Os resultados destes questionários foram armazenados numa base de dados informática, com recurso ao SPSS- Statistical Package for Social Sciences, também utilizado como instrumento de tratamento da informação, assim como a folha de cálculo Excel. Dos resultados da nossa investigação, ressalta que o comércio chinês tem dinamizado muito o tecido comercial sãovicentino, contribuindo para a criação de novos postos de trabalho, diversificando as ofertas e estabilizando ou levando mesmo à redução do preço dos produtos, o que vem generalizar as possibilidades de consumo a segmentos da população menos solventes, que até então tinham muita dificuldade em comprar bens como brinquedos ou certos artigos para o lar. De realçar também que, entre o comércio chinês e o comércio local, existe para além da concorrência como é óbvio, uma certa complementaridade. Esta relação recíproca é estabelecida através de aquisição e revenda de produtos diversificados adquiridos aos comerciantes locas, permitindo assim oferecer assim mais produtos e de melhor qualidade aos seus clientes. Todavia, conclui-se que o comércio chinês, com todas as implicações que trás, ainda não constitui um vector central do desenvolvimento da ilha, designadamente se entendermos o desenvolvimento numa perspectiva abrangente e integral, que incorpora dimensões culturais, sociais e ecológicas que ultrapassam a esfera económica. Contudo, pode-se dizer que a presença do comércio chinês na ilha tem sido bastante positiva, uma vez que coloca no mercado uma diversidade de produtos a preços razoavelmente acessíveis, contribuindo para melhorar a qualidade de vida dos São Vicentinos.

Wage inequality in a frictional labor market

Wage inequality in the United States has grown substantially in thepast two decades. Standard supply-demand analysis in the empiricsof inequality (e.g.Katz and Murphy (1992)) indicates that we mayattribute some of this trend to an outward shift in the demand forhigh skilled labor. In this paper we examine a simple static channelin which the wage premium for skill may grow -increased firm entry.We consider a model of wage dispersion where there are two types ofworkers and homogeneous firms must set wages and preferences forwhat type of worker they would like to hire. We find that both thewage differential and the demand for high skill workers can increasewith the proportion of high skill workers -these high skill workerstherefore 'create' their own demand without exogenous factors. Inaddition, within group wage inequality can increase in step with thebetween group wage inequality. Simulations of the model are providedin order to compare the findings with empirical results.

On the artificial creation of the EL2 center by means of boron implantation in gallium arsenide

In the present work, an analysis of the dark and optical capacitance transients obtained from Schottky Au:GaAs barriers implanted with boron has been carried out by means of the isothermal transient spectroscopy (ITS) and differential and optical ITS techniques. Unlike deep level transient spectroscopy, the use of these techniques allows one to easily distinguish contributions to the transients different from those of the usual deep trap emission kinetics. The results obtained show the artificial creation of the EL2, EL6, and EL5 defects by the boron implantation process. Moreover, the interaction mechanism between the EL2 and other defects, which gives rise to the U band, has been analyzed. The existence of a reorganization process of the defects involved has been observed, which prevents the interaction as the temperature increases. The activation energy of this process has been found to be dependent on the temperature of the annealing treatment after implantation, with values of 0.51 and 0.26 eV for the as‐implanted and 400 °C annealed samples, respectively. The analysis of the optical data has corroborated the existence of such interactions involving all the observed defects that affect their optical parameters

Diffractive J/Psi photoproduction in a dual model

J/psi photoproduction is studied in the framework of the analytic S-matrix theory. The differential and integrated elastic cross sections for J/psi photoproduction are calculated from a dual amplitude with Mandelstam analyticity. It is argued that, at low energies, the background, which is the low-energy equivalent of the high-energy diffraction, replaces the Pomeron exchange. The onset of the high-energy Pomeron dominance is estimated from the fits to the data.

Exclusive J/Psi electroproduction in a dual model

Exclusive J/Psi electroproduction is studied in the framework of the analytic S-matrix theory. The differential and integrated elastic cross sections are calculated using the modified dual amplitude with Mandelstam analyticity model. The model is applied to the description of the available experimental data and proves to be valid in a wide region of the kinematical variables s, t, and Q(2). Our amplitude can be used also as a universal background parametrization for the extraction of tiny resonance signals.

Thin Bonded Portland Cement Concrete Overlay, HR-520, 1990

A four and one-half inch thick, bonded portland cement concrete (PCC) overlay and integral widening were used to rehabilitate a 4.5 mile section of Iowa route 141 from US 169 to Iowa 210 in Dallas County. There was a substantial amount of cracking in the old 20 feet wide PCC pavement. Most of the widening, which was tied to the original slab by dowel bars, was placed as a four feet wide section on one side. Coring has shown that the overlay is well bonded and testing with the Delamtect has shown less than 1% debonding. Midpanel transverse cracks in the old pavement have reflected through the overlay (as expected). Some new transverse cracking has occurred. This cracking has not caused any significant problems. In general, the overlay is performing quite well.