Celiac disease diagnosis and gluten-free food analytical control

Celiac disease (CD) is an autoimmune enteropathy, characterized by an inappropriate T-cell-mediated immune response to the ingestion of certain dietary cereal proteins in genetically susceptible individuals. This disorder presents environmental, genetic, and immunological components. CD presents a prevalence of up to 1% in populations of European ancestry, yet a high percentage of cases remain underdiagnosed. The diagnosis and treatment should be made early since untreated disease causes growth retardation and atypical symptoms, like infertility or neurological disorders. The diagnostic criteria for CD, which requires endoscopy with small bowel biopsy, have been changing over the last few decades, especially due to the advent of serological tests with higher sensitivity and specificity. The use of serological markers can be very useful to rule out clinical suspicious cases and also to help monitor the patients, after adherence to a gluten-free diet. Since the current treatment consists of a life-long glutenfree diet, which leads to significant clinical and histological improvement, the standardization of an assay to assess in an unequivocal way gluten in gluten-free foodstuff is of major importance.

Characterizations of power indices based on null player free winning coalitions

In this paper, we characterize two power indices introduced in [1] using two different modifications of the monotonicity property first stated by [2]. The sets of properties are easily comparable among them and with previous characterizations of other power indices.

Facile synthesis of freestanding Si nanowire arrays by one-step template-free electro-deoxidation of SiO2 in molten salt

This communication presents a novel kind of silicon nanomaterial: freestanding Si nanowire arrays (Si NWAs), which are synthesized facilely by one-step template-free electro-deoxidation of SiO2 in molten CaCl2. The self-assembling growth process of this material is also investigated preliminarily.

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.

Ligand-Induced structural changes in TEM‑1 probed by molecular dynamics and relative binding free energy calculations

The TEM family of enzymes has had a crucial impact on the pharmaceutical industry due to their important role in antibiotic resistance. Even with the latest technologies in structural biology and genomics, no 3D structure of a TEM- 1/antibiotic complex is known previous to acylation. Therefore, the comprehension of their capability in acylate antibiotics is based on the protein macromolecular structure uncomplexed. In this work, molecular docking, molecular dynamic simulations, and relative free energy calculations were applied in order to get a comprehensive and thorough analysis of TEM-1/ampicillin and TEM-1/amoxicillin complexes. We described the complexes and analyzed the effect of ligand binding on the overall structure. We clearly demonstrate that the key residues involved in the stability of the ligand (hot-spots) vary with the nature of the ligand. Structural effects such as (i) the distances between interfacial residues (Ser70−Oγ and Lys73−Nζ, Lys73−Nζ and Ser130−Oγ, and Ser70−Oγ−Ser130−Oγ), (ii) side chain rotamer variation (Tyr105 and Glu240), and (iii) the presence of conserved waters can be also influenced by ligand binding. This study supports the hypothesis that TEM-1 suffers structural modifications upon ligand binding.

An architecture for reliable distributed computer-controlled systems

In Distributed Computer-Controlled Systems (DCCS), both real-time and reliability requirements are of major concern. Architectures for DCCS must be designed considering the integration of processing nodes and the underlying communication infrastructure. Such integration must be provided by appropriate software support services. In this paper, an architecture for DCCS is presented, its structure is outlined, and the services provided by the support software are presented. These are considered in order to guarantee the real-time and reliability requirements placed by current and future systems.

Multi-μ: an Ada 95 based architecture for fault tolerance support of real-time systems

This paper presents an architecture (Multi-μ) being implemented to study and develop software based fault tolerant mechanisms for Real-Time Systems, using the Ada language (Ada 95) and Commercial Off-The-Shelf (COTS) components. Several issues regarding fault tolerance are presented and mechanisms to achieve fault tolerance by software active replication in Ada 95 are discussed. The Multi-μ architecture, based on a specifically proposed Fault Tolerance Manager (FTManager), is then described. Finally, some considerations are made about the work being done and essential future developments.

Specification of software architecture reconfiguration

In the past years, Software Architecture has attracted increased attention by academia and industry as the unifying concept to structure the design of complex systems. One particular research area deals with the possibility of reconfiguring architectures to adapt the systems they describe to new requirements. Reconfiguration amounts to adding and removing components and connections, and may have to occur without stopping the execution of the system being reconfigured. This work contributes to the formal description of such a process. Taking as a premise that a single formalism hardly ever satisfies all requirements in every situation, we present three approaches, each one with its own assumptions about the systems it can be applied to and with different advantages and disadvantages. Each approach is based on work of other researchers and has the aesthetic concern of changing as little as possible the original formalism, keeping its spirit. The first approach shows how a given reconfiguration can be specified in the same manner as the system it is applied to and in a way to be efficiently executed. The second approach explores the Chemical Abstract Machine, a formalism for rewriting multisets of terms, to describe architectures, computations, and reconfigurations in a uniform way. The last approach uses a UNITY-like parallel programming design language to describe computations, represents architectures by diagrams in the sense of Category Theory, and specifies reconfigurations by graph transformation rules.

Maximizing contention-free executions in multiprocessor scheduling

It is widely assumed that scheduling real-time tasks becomes more difficult as their deadlines get shorter. With deadlines shorter, however, tasks potentially compete less with each other for processors, and this could produce more contention-free slots at which the number of competing tasks is smaller than or equal to the number of available processors. This paper presents a policy (called CF policy) that utilizes such contention-free slots effectively. This policy can be employed by any work-conserving, preemptive scheduling algorithm, and we show that any algorithm extended with this policy dominates the original algorithm in terms of schedulability. We also present improved schedulability tests for algorithms that employ this policy, based on the observation that interference from tasks is reduced when their executions are postponed to contention-free slots. Finally, using the properties of the CF policy, we derive a counter-intuitive claim that shortening of task deadlines can help improve schedulability of task systems. We present heuristics that effectively reduce task deadlines for better scheduability without performing any exhaustive search.

EMMON: a system architecture for large- scale, dense and real-time WSNs

In spite of the significant amount of scientific work in Wireless Sensor Networks (WSNs), there is a clear lack of effective, feasible and usable WSN system architectures that address both functional and non-functional requirements in an integrated fashion. This poster abstract outlines the EMMON system architecture for large-scale, dense, real-time embedded monitoring. EMMON relies on a hierarchical network architecture together with integrated middleware and command&control mechanisms. It has been designed to use standard commercially– available technologies, while maintaining as much flexibility as possible to meet specific applications’ requirements. The EMMON WSN architecture has been validated through extensive simulation and experimental evaluation, including through a 300+ node test-bed, the largest WSN test-bed in Europe to date

Poster: EMMON: a WSN system architecture and toolset for large-scale and dense real-time embedded monitoring

Wireless sensor networks (WSNs) have attracted growing interest in the last decade as an infrastructure to support a diversity of ubiquitous computing and cyber-physical systems. However, most research work has focused on protocols or on specific applications. As a result, there remains a clear lack of effective and usable WSN system architectures that address both functional and non-functional requirements in an integrated fashion. This poster outlines the EMMON system architecture for large-scale, dense, real-time embedded monitoring. It provides a hierarchical communication architecture together with integrated middleware and command and control software. It has been designed to maintain as much as flexibility as possible while meeting specific applications requirements. EMMON has been validated through extensive analytical, simulation and experimental evaluations, including through a 300+ nodes test-bed the largest single-site WSN test-bed in Europe.

EMMON: a WSN system architecture for large scale and dense real-time embedded monitoring

Wireless sensor networks (WSNs) have attracted growing interest in the last decade as an infrastructure to support a diversity of ubiquitous computing and cyber-physical systems. However, most research work has focused on protocols or on specific applications. As a result, there remains a clear lack of effective, feasible and usable system architectures that address both functional and non-functional requirements in an integrated fashion. In this paper, we outline the EMMON system architecture for large-scale, dense, real-time embedded monitoring. EMMON provides a hierarchical communication architecture together with integrated middleware and command and control software. It has been designed to use standard commercially-available technologies, while maintaining as much flexibility as possible to meet specific applications requirements. The EMMON architecture has been validated through extensive simulation and experimental evaluation, including a 300+ node test-bed, which is, to the best of our knowledge, the largest single-site WSN test-bed in Europe to date.

Molecular mobility of n-ethylene glycol dimethacrylate glass formers upon free radical polymerization

Quando um líquido evita a cristalização durante o arrefecimento, diz-se que entra no estado sobrearrefecido. Se a temperatura continuar a diminuir, o consequente aumento da viscosidade reflecte-se na mobilidade molecular de tal maneira que os tempos característicos se tornam da mesma ordem de grandeza que os tempos acessíveis experimentalmente. Se o arrefecimento continuar, o líquido altamente viscoso acaba por vitrificar, i.e. entra no estado vítreo onde apenas os movimentos locais são permitidos. Os monómeros da família n -etileno glicol dimetacrilato ( n -EGDMA, para n = 1 até 4, que constituem o objecto deste estudo, facilmente evitam a cristalização, sendo pois bons candidatos para estudar a mobilidade molecular nos estados sobrearrefecido e vítreo. A Espectroscopia de Relaxação Dieléctrica (DRS) foi a técnica escolhida para obter informação detalhada sobre a sua dinâmica molecular (Capítulos 1 e 2). A primeira parte deste trabalho consistiu na caracterização dieléctrica dos processos de relaxação existentes acima e abaixo da temperatura de transição vítrea (g T ), a qual aumenta com o aumento do peso molecular (w M ), sendo este resultado confirmado por Calorimetria Diferencial de Varrimento (DSC). No que respeita ao processo cooperativo a , associado à transição vítrea, e ao processo secundário b, observa-se uma dependência com w M , enquanto que o outro processo secundário, g , aparenta ser independente deste factor (Capítulo 3). Nos capítulos seguintes, foram levadas a cabo diferentes estratégias com o objectivo de clarificar os mecanismos que estão na origem destas duas relaxações secundárias (b e g ), assim como conhecer a sua respectiva relação com a relaxação principal (a ). Do estudo, em tempo real, da polimerização isotérmica via radicais livres do TrEGDMA por Calorimetria de Varrimento Diferencial com Modulação de Temperatura (TMDSC), levado a cabo a temperaturas abaixo da g T do polímero final, concluem-se entre outros, dois importantes aspectos: i) que a vitrificação do polímero em formação conduz a graus de conversão relativamente baixos, e ii) que o monómero que está por reagir é expulso da rede polimérica que se forma, dando lugar a uma clara separação de fases (Capítulo 4). Com base nesta informação, o passo seguinte foi estudar separadamente a polimerização isotérmica do di-, tri- e tetra-EGDMA, dando especial atenção às alterações de mobilidade do monómero ainda por reagir. Com as restrições impostas pela formação de ligações químicas, as relaxações a e b detectadas no monómero tendem a desaparecer no novo polímero formado, enquanto que a relaxação g se mantém quase inalterada. Os diferentes comportamentos que aparecem durante a polimerização permitiram a atribuição da origem molecular dos processos secundários: o processo g foi associado ao movimento twisting das unidades etileno glicol, enquanto que a rotação dos grupos carboxilo foi relacionada com a relaxação b (Capítulo 5). No que respeita ao próprio polímero, um processo de relaxação adicional foi detectado, pol b , no poly-DEGDMA, poly-TrEGDMA e poly-TeEGDMA, com características similares ao encontrado nos poli(metacrilato de n -alquilo). Este processo foi confirmado e bem caracterizado aquando do estudo da copolimerização do TrEGDMA com acrilato de metilo (MA) para diferentes composições (Capítulo 6). Para finalizar, o EGDMA, o elemento mais pequeno da família de monómeros estudada, além de vitrificar apresenta uma marcada tendência para cristalizar quer a partir do estado líquido ou do estado vítreo. Durante a cristalização, a formação de uma fase rígida afecta principalmente o processo a , cuja intensidade diminui sem no entanto se observarem modificações significativas na dependência do tempo de relaxação característico com a temperatura. Por outro lado, o processo secundário b torna-se melhor definido e mais estreito, o que pode ser interpretado em termos de uma maior homogeneidade dos micro-ambientes associados aos movimentos locais(Capítulo 7).

Bridge architecture to interconnect hybrid wired/wireless PROFIBUS networks

The integration of wired and wireless technologies in modern manufacturing plants is now of paramount importance for the competitiveness of any industry. Being PROFIBUS the most widely used technology in use for industrial communications, several solutions have been proposed to provide PROFIBUS networks with wireless communications. One of them, the bridge-based hybrid wired/wireless PROFIBUS network approach, proposes an architecture in which the Intermediate Systems operate at Data Link Layer level, as bridges. In this paper, we propose an architecture for the implementation of such a bridge and the required protocols to handle communication between stations in different domains and the mobility of wireless stations.

Collision-free beacon scheduling mechanisms for IEEE 802.15.4/Zigbee cluster-tree wireless sensor networks

The recently standardized IEEE 802.15.4/Zigbee protocol stack offers great potentials for ubiquitous and pervasive computing, namely for Wireless Sensor Networks (WSNs). However, there are still some open and ambiguous issues that turn its practical use a challenging task. One of those issues is how to build a synchronized multi-hop cluster-tree network, which is quite suitable for QoS support in WSNs. In fact, the current IEEE 802.15.4/Zigbee specifications restrict the synchronization in the beacon-enabled mode (by the generation of periodic beacon frames) to star-based networks, while it supports multi-hop networking using the peer-to-peer mesh topology, but with no synchronization. Even though both specifications mention the possible use of cluster-tree topologies, which combine multi-hop and synchronization features, the description on how to effectively construct such a network topology is missing. This paper tackles this problem, unveils the ambiguities regarding the use of the cluster-tree topology and proposes two collision-free beacon frame scheduling schemes. We strongly believe that the results provided in this paper trigger a significant step towards the practical and efficient use of IEEE 802.15.4/Zigbee cluster-tree networks.