Liquid Intersection Types

We present a new type system combining refinement types and the expressiveness of intersection type discipline. The use of such features makes it possible to derive more precise types than in the original refinement system. We have been able to prove several interesting properties for our system (including subject reduction) and developed an inference algorithm, which we proved to be sound.Comment: In Proceedings ITRS 2014, arXiv:1503.0437

A model of university choice: an exploratory approach

In order to attract the best students, institutions of higher education need to understand how students select colleges and universities (Kotler and Fox, 1995). Understanding the choice process of a university is an instrument with high potential for developing universities marketing strategies (Plank and Chiagouris, 1997). Although many studies have tried to investigate which criteria students use to select a college or university, few have tried to analyse this trough a model that allows the interaction of all these criteria. This study presents a model of university choice, analysed through structural equations modelling using the Partial Least Squares approach.Marketing; student recruitment and selection; high institution development; strategic planning

Identification of spatial patterns in the distribution of meningitis in the State of Mato Grosso - Brazil, from 2007 to 2019

Objective: to analyze the underreporting of meningitis records in the state of Mato Grosso, under conditions of vulnerability, based on spatial analysis. Methodology: Meningitis cases and estimated population were collected from DataSUS, organized by municipality of residence in the state of Mato Grosso and year of notification. Incidence rates were calculated by dividing the number of cases by the population, multiplying the result by 100,000. For spatial autocorrelation analysis, mean rates were used for the entire period, in addition to the variables percentage of poor, percentage of the population living in households with toilets and running water, and Municipal Human Development Index - Income (MHDI Income), obtained from the Atlas of Human Development in Brazil. Results: in general, inverse autocorrelation was observed for the percentage variable of the population living in households with toilets and running water, with municipalities in the center and southeast of the state under high-high autocorrelation and municipalities in the northwest and northeast under low -low. As for the MHDI Income, cities in the center presented high-high autocorrelation and cities in the south and northwest, low-low. Conclusion: the scenario suggests that there is underreporting of meningitis cases in Mato Grosso, as situations marked by less privileged socioeconomic conditions are risk factors for disease transmission. Improvement of health services is suggested, seeking equitable public policies that aim to reduce the existing inequalities in this country

On the hardware and software architecture of the robuter mobile platform: a hands-on approach

The Robuter is a robotic mobile platform that is located in the “Hands-On” Laboratory of the IPP-Hurray! Research Group, at the School of Engineering of the Polytechnic Institute of Porto. Recently, the Robuter was subject of an upgrading process addressing two essential areas: the Hardware Architecture and the Software Architecture. This upgrade in process was triggered due to technical problems on-board of the robot and also to the fact that the hardware/software architecture has become obsolete. This Technical Report overviews the most important aspects of the new Hardware and Software Architectures of the Robuter. This document also presents a first approach on the first steps towards the use of the Robuter platform, and provides some hints on future work that may be carried out using this mobile platform

On a test-bed application for the ART-WiSe framework

This report describes the development of a Test-bed Application for the ART-WiSe Framework with the aim of providing a means of access, validate and demonstrate that architecture. The chosen application is a kind of pursuit-evasion game where a remote controlled robot, navigating through an area covered by wireless sensor network (WSN), is detected and continuously tracked by the WSN. Then a centralized control station takes the appropriate actions for a pursuit robot to chase and “capture” the intruder one. This kind of application imposes stringent timing requirements to the underlying communication infrastructure. It also involves interesting research problems in WSNs like tracking, localization, cooperation between nodes, energy concerns and mobility. Additionally, it can be easily ported into a real-world application. Surveillance or search and rescue operations are two examples where this kind of functionality can be applied. This is still a first approach on the test-bed application and this development effort will be continuously pushed forward until all the envisaged objectives for the Art-WiSe architecture become accomplished

Real-time communications over wired/wireless PROFIBUS networks supporting inter-cell mobility

PROFIBUS is an international standard (IEC 61158, EN 50170) for factory-floor communications, with several thousands of installations worldwide. Taking into account the increasing need for mobile devices in industrial environments, one obvious solution is to extend traditional wired PROFIBUS networks with wireless capabilities. In this paper, we outline the major aspects of a hybrid wired/wireless PROFIBUS-based architecture, where most of the design options were made in order to guarantee the real-time behaviour of the overall network. We also introduce the timing unpredictability problems resulting from the co-existence of heterogeneous physical media in the same network. However, the major focus of this paper is on how to guarantee real-time communications in such a hybrid network, where nodes (and whole segments) can move between different radio cells (inter-cell mobility). Assuming a simple mobility management mechanism based on mobile nodes performing periodic radio channel assessment and switching, we propose a methodology to compute values for specific parameters that enable an optimal (minimum) and bounded duration of the handoff procedure

A relação entre parâmetros fisiológicos, desempenho desportivo e possibilidade de despiste de patologias através de testes realizados durante o nado

O objetivo do estudo foi compreender a resposta fisiológica de nadadores imediatamente abaixo e acima da velocidade no estado estacionário máximo de lactato (vEEML) e observar a relação de parâmetros da cinética do consumo oxigénio (V̇O2) com o desempenho na natação. Nadadores de competição (N = 12) completaram 400 m e 800 m máximos para caracterização do desempenho e determinação da velocidade aeróbia máxima (VAM). Um teste progressivo e a determinação direta do EEML tiveram lugar em diferentes dias assim como transições de 500 m para determinação da cinética do V̇O2. Verificou-se que a vEEML representa o limite de estabilidade de variáveis fisiológicas e delimita a intensidade de exercício relativamente ao surgir de desequilíbrios e caminho para o acumular de fadiga e exaustão. A cinética do V̇O2 da fase primária revelou-se associada com o desempenho, podendo igualmente constituir-se como uma ferramenta útil no despiste de patologias detectáveis durante o exercício quer em indivíduos regularmente treinados, quer em indivíduos que treinam de forma recreativa

Communication protocol for the rempli project

The overall goal of the REMPLI project is to design and implement a communication infrastructure for distributed data acquisition and remote control operations using the power grid as the communication medium. The primary target application is remote meter reading with high time resolution, where the meters can be energy, heat, gas, or water meters. The users of the system (e.g. utility companies) will benefit from the REMPLI system by gaining more detailed information about how energy is consumed by the end-users. In this context, the power-line communication (PLC) is deployed to cover the distance between utility company’s Private Network and the end user. This document specifies a protocol for real-time PLC, in the framework of the REMPLI project. It mainly comprises the Network Layer and Data Link Layer. The protocol was designed having into consideration the specific aspects of the network: different network typologies (star, tree, ring, multiple paths), dynamic changes in network topology (due to network maintenance, hazards, etc.), communication lines strongly affected by noise

Estrogens regulate the survival and death communication between Sertoli and germ cells: a clue for male infertility?

In the last decades estrogens have been regarded as “male hormones” playing an important role controlling male reproductive function. However, the effect of estrogens regulating testicular function and the spermatogenic process it is not fully addressed. Estrogenic actions in target tissues, including testis, are mediated by hormone interaction with the classical estrogens receptors (ER and ER) and also via the membrane G-protein coupled receptor (GPR30/GPER). Ultimately, the estrogens alter the gene expression network in cells and tissues modulating its functioning. Male fertility relies on a successful spermatogenesis, which is dependent from the support of Sertoli cells (SCs), the somatic cells within seminiferous tubules (SeT). Apoptosis is a key event strictly maintaining the appropriate ratio between germ cells and SCs and, thus, it is crucial to maintain the spermatogenic output. It has been suggested that SCs play a crucial role controlling germ cells fate, by secretion of survival and death factors, which act on receptors in germ cells. These include the survival factor desert hedgehog (Dhh), the stem cell factor (SCF) and its receptor the c-kit, as well as the death factors Fas-Ligand (FasL) and Fas-receptor (FasR). It has been shown that estrogens regulate Dhh, SCF, c-kit, FasL and FasR expression in several other tissues. Therefore, we hypothesize that estrogens may influence germ cell survival or death in testicular cells by governing the expression of SCF, c-kit, FasL, FasR. In the present work rat SeT and SCs were cultured in presence or absence of 100nM of 17β-estradiol (E2), and the expression of the aforementioned factors was studied through real-time PCR and Western blot techniques. In addition, in order to start elucidating the molecular mechanisms by which the estrogenic effects are attained, SCs were cultured with E2 0,1nM and with 100nM of each ER specific agonist: G1, DPN and PPT, respectively, agonists for GPER, ERand ER. E2 down-regulated the c-kit expression while increasing expression of its ligand, SCF, both in SeT and SCs. The expression of Fas system, FasR and FasL was also increased in response to E2. No differences were found in Dhh expression between experimental groups. The expression of SCF and FasL in SCs was strongly increased by G1 stimulation indicating the involvement of GPRER. Our results demonstrated that the estrogenic stimulation may modulate germ cell apoptosis in a direct way or through altering germ cell:SCs communication, which could have a profound impact in male fertility, particularly in cases of hyperestrogenism.Nas últimas décadas os estrogénios têm sido considerados hormonas masculinas, desempenhando um papel importante no controlo das funções reprodutivas masculinas. Contudo, o efeito dos estrogénios na regulação das funções testiculares ainda não está completamente abordado. As ações estrogénicas nos tecidos alvo, entre eles o testículo, são mediadas por interações hormonais com os recetores de estrogénios (ER e ER) clássicos e também através do recetor membranar associado à proteína-G (GPR30/GPER). Por fim, os estrogénios alteram a rede de expressão dos genes nas células e nos tecidos, modulando o seu funcionamento. A fertilidade masculina assenta numa espermatogénese bem sucedida, a qual é dependente do suporte das células de Sertoli (SCs), as células somáticas presentes nos túbulos seminíferos (SeT). A apoptose é o evento chave que mantem o ratio apropriado entre as células germinativas e as SCs e desta forma é crucial para manter a qualidade e quantidade do processo espermatogénico. Tem sido sugerido que as SCs desempenham um papel crucial no controlo do destino das células germinativas através da secreção de fatores de sobrevivência/morte, que atuam nos recetores nas células germinativas. Esses incluem o fator de sobrevivência Desert Hedgehog (Dhh), o Stem Cell Factor (SCF) e o seu receptor (c-kit), assim como os fatores de morte Fas Ligando (FasL) e o seu recetor (FasR). Tem sido demonstrado que os estrogénios regulam a expressão do Dhh, SCF, c-kit, FasL e FasR em diversos tecidos. Portanto colocou-se a hipótese de que os estrogénios podem influenciar a sobrevivência ou morte das células testiculares através do controlo da expressão dos referidos genes. Neste trabalho, SeT e SCs de rato foram colocados em cultura na presença ou ausência de 100nM de 17β-estradiol (E2), e a expressão dos fatores acima-citados foi estuda através das técnicas de Real-Time PCR e Western Blot. Além disso, para elucidar qual o mecanismo molecular pelo qual o efeito dos estrogénios é conseguido, SCs foram colocadas em cultura na presença de 100 nM E2 ou 100nM de agonistas específicos para cada um dos recetores: G1, DPN e PPT, respetivamente, agonistas para o GPER, ERα e ERβ. O E2 diminuiu a expressão do c-kit enquanto por sua vez expressão do seu ligando SCF aumentou. Não houve diferenças na expressão do Dhh entre os diferentes grupos experimentais. A expressão do SCF e do FasL nas SCs foi muito aumentada pela estimulação com G1 indicando o envolvimento do GPER. Os nossos resultados demonstram que a estimulação com estrogénios pode moldar a apoptose das células germinativas tanto de uma forma directa como através da alteração da comunicação entre as SCs e as células germinativas, podendo isto ter um profundo impacto na fertilidade masculina em especial nos casos de hiperesteroidismo