Modelling the Duration of Multihop Paths in Mobile Ad Hoc Networks

Mobile ad hoc networks are characterized by having nodes that are cooperative and communicate without any kind of infrastructure. The mobility and multihop capability of these networks leads the network topology to change rapidly and unpredictably; this aspect must be incorporated in effective models to describe the dynamics of multihop paths.\newline When modeling the duration of multihop paths, a great part of the literature assumes that the links of multihop paths behave independently. This simplifies the modeling and reduces the complexity of computations. However, each link shares a common node with each of its neighbor links, turning the independent link assumption ge-nerally not valid. In this paper, we use a piecewise deterministic Markov model that characterizes the random behaviour of a multihop path not assuming independent links. We obtain the mean path duration of multihop paths and compare the results for the used model with the ones obtained by assuming independent links. Numerical results illustrate that independent link approximation results underestimate the mean path duration, with the most significant differences being observed with low node mobility and higher path durations

Probing a M/G/1 queue with general input and service times

We consider the estimation of the arrival rate and the service time moments of a M/G/1 queue with probing, i.e., with special customers (probes) entering the system. The probe inter-arrival times are i.i.d. and probe service times follow a general positive distribution. The only observations used are the arrival times, service times and departure times of probes. We derive the main equations from which the quantities of interest can be estimated. Two particular probe arrivals, deterministic and Poisson, are investigated

On the minimum hop count and connectivity in one-dimensional ad hoc wireless networks

This paper investigates connectivity in one-dimensional ad hoc networks by means of the distribution of the minimum hop count between source and destination nodes. We derive the exact probability distribution of the minimum hop count from the location density of relay nodes in the multihop path selected with the Most Forward within Radius (MFR) scheme. The probability that the source and destination nodes are connected (provided by Ghasemi and Nader-Esfahani [IEEE Commun. Lett. 10(4):251–253, 2006]) can be obtained by summing the probability masses for each possible value of the minimum hop count, which provides new insights to the connectivity probability. Numerical results show the effect of the number of nodes and the transmission range on the minimum hop count

Probing a M/G/1 queue with general input and service times

We consider the estimation of the arrival rate and the service time moments of a $M/G/1$ queue with probing, i.e., with special customers (probes) entering the system. The probe inter-arrival times are i.i.d. and probe service times follow a general positive distribution. The only observations used are the arrival times, service times and departure times of probes. We derive the main equations from which the quantities of interest can be estimated. Two particular probe arrivals, deterministic and Poisson, are investigated

HLA-DR in Cytotoxic T lymphocytes predicts breast cancer patients' response to neoadjuvant chemotherapy

Prediction of breast cancer response to Neoadjuvant Chemotherapy (NACT) is an urgent need to promptly direct non-responder patients to alternative therapies. Infiltrating T lymphocytes, namely cytotoxic T lymphocytes (CTLs) have been appointed as predictors of response. However, cancer cells have the ability to dampen CTLs' activity and thus, the prognostic value of the CTLs, per se, is debatable. Here, we disclose that more than the occurrence of CTLs, it is their activation state, revealed by HLA-DR expression, that can accurately predict response to NACT. Flow cytometry analysis of breast cancer biopsies showed that the frequency of CTLs and other lymphocytes were similar regardless disease stage and between NACT responders and non-responders. However, only breast cancer patients without axillary lymph node metastasis and NACT responders have HLA-DRhi CTLs. Interestingly, HLA-DR levels in tumor CTLs is correlated with HLA-DR levels in systemic CTLs. These HLA-DR+ CTLs produce IFN-γ and Granzyme B, enlightening their effector and probable anti-tumor activity profile. Moreover, the level of HLA-DR in CTLs is negatively correlated with the level of HLA-DR in T regulatory lymphocytes and with immunosuppressive and pro-tumor molecules in the tumor microenvironment. Hence, HLA-DR levels in CTLs is a highly sensitive and specific potential predictive factor of NACT-response, which can be assessed in blood to guide therapeutic decisions.Fundacao para a Ciencia e Tecnologia: PD/BD/114023/2015; PTDC/BBB-BMD/4497/2014. Liga Portuguesa Contra o Cancroinfo:eu-repo/semantics/publishedVersio

An analytical framework to infer multihop path reliability in MANETs

Due to complexity and intractability reasons, most of the analytical studies on the reliability of communication paths in mobile ad hoc networks are based on the assumption of link independence. In this paper, an analytical framework is developed to characterize the random behavior of a multihop path and derive path metrics to characterize the reliability of paths. This is achieved through the modeling of a multihop path as a PDMP (piecewise deterministic Markov process). Two path based metrics are obtained as expectations of functionals of the process: the mean path duration and the path persistence. We show that these metrics are the unique solution of a set of integro-differential equations and provide a recursive scheme for their computation. Finally, numerical results illustrate the computation of the metrics; these results are compared with independent link approximation results

A influência da política fiscal na competitividade da economia no âmbito dos países da União Europeia: alguns determinantes

A capacidade de atração de Investimento Direto Estrangeiro (IDE) é um fator a considerar ao aferir a competitividade da economia de um Estado. Esta tese pretende demonstrar a existência de uma relação entre políticas fiscais e a capacidade de atrair IDE e, por essa via, pretende demonstrar que as políticas fiscais são fatores relevantes na competitividade das economias dos países objeto de estudo. A tese é constituída por três ensaios distintos, mas inter-relacionados. No primeiro ensaio procede-se a uma revisão da literatura acerca dos diversos fatores que influenciam as decisões de IDE e conclui que algumas políticas fiscais são determinantes na captação de IDE. Os dois outros ensaios analisam o impacto de certas políticas fiscais específicas na captação de IDE. Mais concretamente, o segundo ensaio procura avaliar a existência de uma relação entre a captação de IDE e os regimes fiscais de reporte de prejuízos fiscais. O terceiro ensaio versa sobre o impacto das regras fiscais de tributação de dividendos e de subcapitalização na capacidade de atrair IDE. O objetivo do estudo é contribuir para um melhor conhecimento da relevância, na captação de IDE, das diversas políticas fiscais de dividendos, de subcapitalização e de reporte de prejuízos, vigentes em diferentes Estados Europeus. Com tal objetivo, no segundo e no terceiro ensaios analisam-se comparativamente os regimes específicos em 7 países da Europa Ocidental. Os ensaios chegaram a um conjunto coerente de conclusões, utilizando como metodologia de análise a fuzzy set – Qualitative Comparative Analyis (fsQCA). Mais concretamente a análise fsQCA fornece evidência empírica de que a tributação dos dividendos e os regimes fiscais de subcapitalização e de reporte de prejuízos são condições centrais para a verificação do resultado (as decisões de IDE), na medida em que essas condições integram as soluções simples e as soluções intermédias, resultantes da aplicação do modelo de análise. No âmbito da análise foram também consideradas outras variáveis, não relacionadas com a política fiscal, como condições para a verificação do resultado. A análise fsQCA revela que o Produto Interno Bruto em Paridade do Poder de Compra (GDPppp) é condição periférica para a verificação do resultado; Abstract: The attractiveness of Foreign Direct Investment (FDI) is a factor to consider when assessing the competitiveness of a State economy. This thesis intends to demonstrate the existence of a relationship between fiscal policies and the capacity to attract FDI and by this way the thesis intends to demonstrate fiscal policies are relevant factors in economies competitiveness of the countries under study. The thesis consists of three distinct but interrelated essays. The first essay is about literature review on the various factors that influence FDI decisions and concludes some fiscal policies are determinant in attracting FDI. The other two papers analyse the impact of certain specific fiscal policies on FDI inflows. More specifically, the second essay tries to evaluate the existence of a link between FDI inflows and tax loss carryforwards. The third essay is about the impact of the dividend withholding tax rules and of thin capitalization tax rules on the ability to attract FDI. The objective of the study is to contribute to a better understanding of the relevance on FDI attractiveness of the taxation policies of dividends, thin capitalization and tax losses, in force in different European States. Looking for the objective above mentioned the second and third essays compare these specific tax regimes in force on seven Western European countries. The studies reached a coherent set of conclusions using the fuzzy set - Qualitative Comparative Analyis (fsQCA). More specifically, the fsQCA analysis provides empirical evidence that dividend taxation and thin capitalization and loss carryover tax regimes are central conditions for outcome verification (FDI decisions), as these conditions integrate simple solutions and the intermediate solutions, resulting from the application of the model analysis. In the scope of the analysis, other variables, not related to fiscal policy, were also considered as conditions for the verification of the result. The fsQCA analysis reveals that the Gross Domestic Product in Purchasing Power Parity (GDPppp) is a peripheral condition for the verification of the result

Ganhos dos cuidados de enfermagem de reabilitação nas pessoas em cuidados intensivos com alterações do foro respiratório, com base num modelo de autocuidado

Enquadramento: O aumento da esperança média de vida tem aumentado a necessidade de cuidados intensivos. Nestas unidades as pessoas permanecem sob suporte ventilatório, permanecendo no leito por longos períodos. Cabe ao enfermeiro de reabilitação intervir, diminuindo a dependência e promovendo o autocuidado, condicionando uma melhor qualidade de vida. Objetivo: Mostrar o processo subjacente à aquisição de competências. Metodologia: Foi implementado um projeto de intervenção profissional utilizando o Índice de Barthel e a Elderly Nursing Core Set como instrumentos de colheita de dados, com o objetivo de identificar os ganhos sensíveis aos cuidados de enfermagem de reabilitação. Resultados: Constata-se através da análise dos dados que as intervenções do enfermeiro de reabilitação contribuíram para uma melhoria funcional da pessoa, diminuindo a dependência no autocuidado. Conclusão: Todas as pessoas incluídas na estratégia de intervenção profissional melhoraram funcionalmente, tendo sido adquiridas as competências de Enfermeiro Especialista em Reabilitação e de Mestre neste processo

Streamlining Literature Reviews Using an Automatic and Flexible Data Gathering and Classification Platform

Literature reviews are a crucial but time-consuming and complex task in scientific research. As such, interest in automating this process using machine learning techniques has increased over the last few years. In this paper, we present a method of streamlining the process of writing literature reviews by automating several aspects of the process using Maestro v2023, an automatic and flexible data gathering and classification platform. Maestro v2023 is a revamped version of the original Maestro platform, designed to be modular and configurable, allowing users in an organization to create search contexts that automatically gather and classify data for them. We analyze the work related to literature review automation and suggest how Maestro can contribute to this field, demonstrating how the system was utilized in order to streamline our own literature review process, as well aid us in formulating the abstract and extracting relevant keywords to this paper

An amputation resets positional information to a proximal identity in the regenerating zebrafish caudal fin

We thank Lara Carvalho and Fabio Valerio for excellent zebrafish husbandry, Andreia Pinto for histology and Antonio Temudo for imaging support. We are grateful to C. Certal and S. Pascoal for comments on the manuscript. A. S. A and S. S were supported by FCT fellowships (SFRH/BD/33179/2007 and SFER/BD/32952/2006). L. S. was supported by two FCT grants (PTDC/SAU-OBD/64628/2006 and PTDC/SAU-OBD/100202/2008) and A.J. was supported by one FCT grant (PTDC/SAU-OBD/100200/2008).Background: Zebrafish has emerged as a powerful model organism to study the process of regeneration. This teleost fish has the ability to regenerate various tissues and organs like the heart, spinal cord, retina and fins. In this study, we took advantage of the existence of an excellent morphological reference in the zebrafish caudal fin, the bony ray bifurcations, as a model to study positional information upon amputation. We investigated the existence of positional information for bifurcation formation by performing repeated amputations at different proximal-distal places along the fin. Results: We show that, while amputations performed at a long distance from the bifurcation do not change its final proximal-distal position in the regenerated fin, consecutive amputations done at 1 segment proximal to the bifurcation (near the bifurcation) induce a positional reset and progressively shift its position distally. Furthermore, we investigated the potential role of Shh and Fgf signalling pathways in the determination of the bifurcation position and observed that they do not seem to be involved in this process. Conclusions: Our results reveal that, an amputation near the bifurcation inhibits the formation of the regenerated bifurcation in the pre-amputation position, inducing a distalization of this structure. This shows that the positional memory for bony ray bifurcations depends on the proximal-distal level of the amputation.publishersversionpublishe