An overview of the higher level classification of Pucciniomycotina based on combined analyses of nuclear large and small subunit rDNA sequences

Mycologia, Vol. 98, nº6

Fractional Dynamics of Computer Virus Propagation

We propose a fractional model for computer virus propagation. The model includes the interaction between computers and removable devices. We simulate numerically the model for distinct values of the order of the fractional derivative and for two sets of initial conditions adopted in the literature. We conclude that fractional order systems reveal richer dynamics than the classical integer order counterpart. Therefore, fractional dynamics leads to time responses with super-fast transients and super-slow evolutions towards the steady-state, effects not easily captured by the integer order models.

New findings on the dynamics of HIV and TB coinfection models

In this paper we study a model for HIV and TB coinfection. We consider the integer order and the fractional order versions of the model. Let α∈[0.78,1.0] be the order of the fractional derivative, then the integer order model is obtained for α=1.0. The model includes vertical transmission for HIV and treatment for both diseases. We compute the reproduction number of the integer order model and HIV and TB submodels, and the stability of the disease free equilibrium. We sketch the bifurcation diagrams of the integer order model, for variation of the average number of sexual partners per person and per unit time, and the tuberculosis transmission rate. We analyze numerical results of the fractional order model for different values of α, including α=1. The results show distinct types of transients, for variation of α. Moreover, we speculate, from observation of the numerical results, that the order of the fractional derivative may behave as a bifurcation parameter for the model. We conclude that the dynamics of the integer and the fractional order versions of the model are very rich and that together these versions may provide a better understanding of the dynamics of HIV and TB coinfection.

Time-domain optimization of amplifiers based on distributed genetic algorithms

Thesis presented in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the subject of Electrical and Computer Engineering

Clinical and laboratory findings of disseminated Mycobacterium avium complex infection (DMAC) in a pair matched case-control study

A pair matched case/control study was conducted from January 1991 to 30 June 1992 in order to define clinical and laboratory findings associated with DMAC infection in AIDS patients. Since DMAC infection is usually associated with advanced immunodeficiency, and therefore also with other opportunistic illnesses, in addition to the number of CD4+ lymphocytes, cases and controls were matched using the following criteria: date of AIDS diagnosis and antiretroviral therapy, number and severity of associated opportunistic infections and, whenever possible, type of Pneumocystis carinii prophylaxis, age and gender, in this order of relevance. Cases (defined as patients presenting at least one positive culture for MAC at a normally sterile site) and controls presented CD4+ lymphocyte counts below 50 cel/mm3. A significantly higher prevalence of general, digestive and respiratory signs, increased LDH levels, low hemoglobin levels and CD4+ cell counts were recorded for cases when compared to controls. Increases in gGT and alkaline phosphatase levels seen in cases were also recorded for controls. In conclusion, the strategy we used for selecting controls allowed us to detect laboratory findings associated to DMAC infection not found in other advanced immunossupressed AIDS patients without DMAC.

Aplicação de um sistema de teledermatologia no Hospital do Divino Espírito Santo nos Açores : análise custo-efectividade

RESUMO - Nos Açores, a telemedicina representa uma mais-valia para os seus habitantes devido à sua dispersão geográfica e aos elevados custos que as instituições de saúde incorrem na deslocação dos utentes e profissionais de saúde. A teledermatologia tem sido referenciada como uma das sub-especialidades da telemedicina, apresentando resultados semelhantes aos da consulta convencional em termos de fiabilidade e precisão no diagnóstico. No contexto açoriano, a teledermatologia pode ajudar a colmatar a falta de resposta por parte das instituições de saúde nesta especialidade, assim como poupar recursos às mesmas. OBJECTIVOS: Pretende-se realizar uma análise de custo-efectividade da teleconsulta em dermatologia no Hospital do Divino Espírito Santo em Ponta Delgada, na perspectiva do hospital, tendo como comparador a consulta convencional. METODOLOGIA: Realizou-se uma revisão da literatura de estudos de custo-efectividade para averiguar os recursos que deveriam ser considerados. Os recursos identificados seriam posteriormente valorizados de acordo com os custos verificados no hospital. RESULTADOS: O custo com o transporte dos doentes representa um peso bastante elevado para o Hospital, assim como a comparticipação de despesas de alojamento e alimentação dos doentes. Dado a constante deslocação de doentes entre as ilhas dos Açores e o Continente, a teledermatologia apresenta-se como uma solução viável em termos de custos e diagnóstico, comparando com a prática convencional. CONCLUSÕES: Na perspectiva do Hospital, a teledermatologia permite reduzir os custos relacionados com o transporte dos doentes entre as ilhas dos Açores e Continente, assim como despesas com alojamento e alimentação, considerados evitáveis. ------- ABSTRACT - In Azores, telemedicine represents an added-value for its population due to its geographic dispersion and to the high costs that health institutions incur to transport patients and health providers. Teledermatology has been highlighted as a telemedicine sub-specialty, presenting similar results comparing to the traditional consult, in terms of precision and reliability. In the Azorean context, teledermatology could help to diminish the lack of response of the health institutions on this specialty, as well as spare its resources. OBJECTIVES: In this project, is intended to carry out a cost-effectiveness analysis of the dermatology teleconsult in the Hospital do Divino Espírito Santo, in Ponta Delgada, on the Hospital perspective, comparing to the conventional consult. METHODOLOGY: A literature revision of cost-effectiveness studies was accomplished in order to find out what resources should be considered. The identified resources would be afterward valued according to the costs verified in the Hospital. RESULTS: The cost associated to the patient transport represents an overweight for the hospital, as well as the expenses reimbursement relating to lodging and others that patients have to incur. Due to the constant transport of patients between the Azores islands and the mainland, teledermatology constitutes a viable solution in terms of cost and diagnosis, comparing to conventional practice. CONCLUSIONS: On the Hospital perspective, teledermatology allows to reduce the costs relating to patients transport between the Azores islands and the mainland, as well as expenses with lodging and others, considered avoidable.

Measurement of lead concentration in biological tissues by atomic spectroscopy techniques

Dissertation for the degree of Doctor of Philosophy in Physics

Fractional Dynamics of Computer Virus Propagation

We propose a fractional model for computer virus propagation. The model includes the interaction between computers and removable devices. We simulate numerically the model for distinct values of the order of the fractional derivative and for two sets of initial conditions adopted in the literature. We conclude that fractional order systems reveal richer dynamics than the classical integer order counterpart. Therefore, fractional dynamics leads to time responses with super-fast transients and super-slow evolutions towards the steady-state, effects not easily captured by the integer order models.

Fractional State Space Analysis of Temperature Time Series

Atmospheric temperatures characterize Earth as a slow dynamics spatiotemporal system, revealing long-memory and complex behavior. Temperature time series of 54 worldwide geographic locations are considered as representative of the Earth weather dynamics. These data are then interpreted as the time evolution of a set of state space variables describing a complex system. The data are analyzed by means of multidimensional scaling (MDS), and the fractional state space portrait (fSSP). A centennial perspective covering the period from 1910 to 2012 allows MDS to identify similarities among different Earth’s locations. The multivariate mutual information is proposed to determine the “optimal” order of the time derivative for the fSSP representation. The fSSP emerges as a valuable alternative for visualizing system dynamics.

Range of motion measurements based on depth camera for clinical rehabilitation

Dissertação para obtenção do Grau de Mestre em Engenharia Biomédica

Adjusting to external imbalances within the EMU, the case of Portugal

From 1995 to 2010 Portugal has accumulated a negative international asset position of 110 percent of GDP. In a developed and aging economy the number is astonishing and any argument to consider it sustainable must rely on extremely favorable forecasts on growth. Portuguese policy options are reduced in number: no autonomous monetary policy, no currency to devaluate, and limited discretion in changing fiscal deficits and government debt. To start the necessary deleveraging a remaining possible policy is a budget-neutral change of the tax structure that increases private saving and net exports. An increase in the VAT and a decrease in the employer’s social security contribution tax can achieve the desired outcome in the short run if they are complemented with wage moderation. To obtain a substantial improvement in competitiveness and a large decrease in consumption, the changes in the tax rates have to be large. While a precise quantitative assessment is difficult, the initial increase in the effective VAT rate needed to allow the social security tax to decrease by 16 percentage points (pp) is approximately 10 pp. Such a large increase in the effective VAT rate could be obtained by raising most of the reduced VAT rates to the new general VAT rate of 23 percent. The empirical analysis shows that over time the suggested tax swap could generate surpluses and improve the trade balance. A temporary version of the suggested tax-swap has the attractiveness to achieve a sharper increase in the private saving rate maintaining the short run gains in competitiveness. Finally, the temporary version of the fiscal devaluation could be the basis for an automatic stabilizer to external imbalances within a monetary union.Portugal has been running large current account deficits every year since 1995. These deficits have accumulated to an astonishing 110 percent of GDP negative external asset position. The sustainability of such a large external position is questionable and must rely on fantastic productivity growth expectations. The recent global financial crisis appears to have anticipated the international investors reality check on those future expectations with the result of a large increase in the cost of external financing. Today the rebalancing of the current account through an increase in national savings and an improvement in competitiveness must be at the top of the Portuguese authorities “to do” list as the cost of a pull out from international investors is of the order of 10% of GDP. The external rebalancing is difficult as the degrees of freedom of the Portuguese authorities are limited in number: they have no autonomous monetary policy, no currency to devaluate, and little discretion in fiscal policy as deficit limits and debt targets are set by the Stability Growth Pact and the postcrisis consensus on medium-term fiscal consolidation. One possibility that remains is to change the fiscal policy mix for a given budget deficit. The purpose of this paper is to explore the effects of a “fiscal devaluation”1 obtained through a tax swap between employers’ social security contributions and taxes on consumption2. The paper begins by illustrating Portugal’s current account evolution during the euro period. The second section section lays out a model to offer a qualitative assessment of the dynamic outcomes of the the tax swap. I show that the suggested tax swap can in theory achieve the desired outcomes in terms of competitiveness and consumption if complemented with moderation (stickiness) in wages. I also study the effects of a temporary version of the tax swap and show that it achieves a sharper improvement in the current account that accelerate the rebalancing. The third section moves to the empirical analysis and estimates the likely effects of the tax swap for the Portuguese economy. The fourth section concludes.

Study of nuclear reactions relevant for astrophysics by Micro-AMS

Dissertação para obtenção do Grau de Doutor em Física

Portuguese average cost of capital

The oldest Portuguese share index still being calculated is the BVL/PSI-General, one which started the daily series on 5/Jan/1988 with a base value of 1000 points. Everyday a single value is computed based on the closing prices of all the shares included in the sample. Also, all corporate events affecting the price of any share beyond market sentiment are taken into account through proper adjustments, either in the numerator or the denominator of the formula. However, for dates before January 1988, there is nothing comparable to this index since the two different series known either never disclosed the methodology adopted to calculate the index or followed solutions not compatible with the above index. The present paper explains the solutions adopted to replicate as closely as possible the methodology of the BVL-General index to the main market of the Lisbon Exchange for the period 1978 – 1987. This is the first estimate of the historical Equity Risk Premium in Portugal above short-term risk-free rate from the re-opening of the market following the Carnation Revolution (and the accompanying nationalizations), to the present. In showing a value of the same order of magnitude found in other countries, the paper invites further studies on the effects of political decisions such as privatizations and joining the European Union.

The main leachate emissions of uncontrolled landfills

Dissertação para obtenção do Grau de Mestre em Engenharia do Ambiente, Perfil de Engenharia Sanitária

Role of surfactants in filtration and fouling of colloidal silica

The EM3E Master is an Education Programme supported by the European Commission, the European Membrane Society (EMS), the European Membrane House (EMH), and a large international network of industrial companies, research centres and universities