Local-field and excitonic effects in the optical response of alpha-alumina

This paper introduces key ingredients of the dielectric response of a-alumina that go beyond an independent-particle (IP) treatment of the valence-electron excitations. The optical-response functions were calculated from first-principles both at the Bethe-Salpeter and the random-phase approximation (RPA) levels. Excitonic effects obtained within the Bethe-Salpeter framework were found essential for reproducing the low-energy part of the experimental spectra (below 15 eV) and the bound exciton in particular. For higher energies, local-field effects introduced through the RPA modified considerably the IP results and provided a satisfactory account of the reflectivity spectra and of the position and shape of the dominant bulk plasmon resonance in the electron energy-loss spectra.

Posttranslational Inhibition of Proinflammatory Chemokine Secretion in Intestinal Epithelial Cells Implications for Specific IBD Indications

Background and Aim: Inflammatory bowel diseases (IBD) are immune-mediated chronic diseases that are characterized by an overreaction of the intestinal immune system to the intestinal microbiota. VSL#3, a mixture of 8 different lactic acid bacteria, is a clinically relevant probiotic compound in the context of IBD, but the bacterial structures and molecular mechanisms underlying the observed protective effects are largely unknown. The intestinal epithelium plays a very important role in the maintenance of the intestinal homeostasis, as the intestinal epithelial cells (IEC) are capable of sensing, processing, and reacting upon signals from the luminal microbiota and the intestinal immune system. This immune regulatory function of the IEC is lost in IBD owing to dysregulated activation of the IEC. Thus, the aim of this study was to reveal protective mechanisms of VSL#3 on IEC function.

Results: In vitro, VSL#3 was found to selectively inhibit activation-induced secretion of the T-cell chemokine interferon-inducible protein (IP)-10 in IEC. Cell wall-associated proteins of VSL#3-derived Lactobacillus casei (L. casei) were identified to be the active anti-inflammatory component of VSL#3. Mechanistically, L. casei did not impair initial IP-10 protein production, but induced posttranslational degradation of IP-10 in IEC. Feeding studies in tumor necrosis factor (TNF)(Delta ARE/+) mice, a mouse model for experimental ileitis, revealed that neither VSL#3 nor L. casei is capable of reducing ileal inflammation. Even preweaning feeding of VSL#3 did not prevent the development of severe ileitis in TNF Delta ARE/+ mice. In contrast, VSL#3 feeding studies in IL-10-/- mice, a model for experimental colitis, revealed that VSL#3 has local, intestinal compartment-specific protective effects on the development of inflammation. Reduced histopathologic inflammation in the cecum of IL-10-/- mice after VSL#3 treatment was found to correlate with reduced levels of IP-10 protein in primary cecal epithelial cells.

Conclusion and Outlook: These results suggest that the inhibitory effect of VSL#3-derived L. casei on IP-10 secretion in IEC is an important probiotic mechanism that contributes to the anti-inflammatory effects of VSL#3 in specific subsets of patients with IBD. An important future aim is the identification of the active probiotic protein, which could serve as a basis for the development of new efficient therapies in the context of IBD.

Serum Inflammatory Markers and Preeclampsia in Type 1 Diabetes:A prospective study

OBJECTIVE Inflammation and endothelial dysfunction have been associated with the immunobiology of preeclampsia (PE), a significant cause of adverse pregnancy outcomes. The prevalence of PE is elevated several fold in the presence of maternal type 1 diabetes mellitus (T1DM). Although cross-sectional studies of pregnancies among women without diabetes have shown altered inflammatory markers in the presence of PE, longitudinal studies of diabetic women are lacking. In maternal serum samples, we examined the temporal associations of markers of inflammation with the subsequent development of PE in women with T1DM. RESEARCH DESIGN AND METHODS We conducted longitudinal analyses of serum C-reactive protein (CRP), adhesion molecules, and cytokines during the first (mean ± SD, 12.2 ± 1.9 weeks), second (21.6 ± 1.5 weeks), and third (31.5 ± 1.7 weeks) trimesters of pregnancy (visits 1-3, respectively). All study visits took place before the onset of PE. Covariates were BMI, HbA1c, age of onset, duration of diabetes, and mean arterial pressure. RESULTS In women with T1DM who developed PE versus those who remained normotensive, CRP tended to be higher at visits 1 (P = 0.07) and 2 (P = 0.06) and was significantly higher at visit 3 (P <0.05); soluble E-selectin and interferon-?-inducible protein-10 (IP-10) were significantly higher at visit 3; interleukin-1 receptor antagonist (IL-1ra) and eotaxin were higher and lower, respectively, at visit 2 (all P <0.05). These conclusions persisted following adjustment for covariates. CONCLUSIONS In pregnant women with T1DM, elevated CRP, soluble E-selectin, IL-1ra, and IP-10 and lower eotaxin were associated with subsequent PE. The role of inflammatory factors as markers and potential mechanisms of the high prevalence of PE in T1DM merits further investigation.

Adaptive Measurement-Based Policy-Driven QoS Management with Fuzzy-Rule-based Resource Allocation

Fixed and wireless networks are increasingly converging towards common connectivity with IP-based core networks. Providing effective end-to-end resource and QoS management in such complex heterogeneous converged network scenarios requires unified, adaptive and scalable solutions to integrate and co-ordinate diverse QoS mechanisms of different access technologies with IP-based QoS. Policy-Based Network Management (PBNM) is one approach that could be employed to address this challenge. Hence, a policy-based framework for end-to-end QoS management in converged networks, CNQF (Converged Networks QoS Management Framework) has been proposed within our project. In this paper, the CNQF architecture, a Java implementation of its prototype and experimental validation of key elements are discussed. We then present a fuzzy-based CNQF resource management approach and study the performance of our implementation with real traffic flows on an experimental testbed. The results demonstrate the efficacy of our resource-adaptive approach for practical PBNM systems

Instrumentation for diagnostics and control of laser-accelerated proton (ion) beams

Suitable instrumentation for laser-accelerated proton (ion) beams is critical for development of integrated, laser-driven ion accelerator systems. Instrumentation aimed at beam diagnostics and control must be applied to the driving laser pulse, the laser-plasma that forms at the target and the emergent proton (ion) bunch in a correlated way to develop these novel accelerators. This report is a brief overview of established diagnostic techniques and new developments based on material presented at the first workshop on 'Instrumentation for Diagnostics and Control of Laser-accelerated Proton (Ion) Beams' in Abingdon, UK. It includes radiochromic film (RCF), image plates (IP), micro-channel plates (MCP), Thomson spectrometers, prompt inline scintillators, time and space-resolved interferometry (TASRI) and nuclear activation schemes. Repetition-rated instrumentation requirements for target metrology are also addressed. (C) 2013 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Intellectual Property and the EU’s Deep Trade Agenda

The EU is considered to be one of the main proponents of what has been called the deep trade agenda—that is, the push for further trade liberalization with an emphasis on the removal of domestic non-tariff regulatory measures affecting trade, as opposed to the traditional focus on the removal of trade barriers at borders. As negotiations on the Doha Development Round have stalled, the EU has attempted to achieve these aims by entering into comprehensive free trade agreements (FTAs) that are not only limited exclusively to tariffs but also extend to non-tariff barriers, including services, intellectual property rights (IPRs), competition, and investment. These FTAs place great emphasis on regulatory convergence as a means to secure greater market openings. The paper examines the EU's current external trade policy in the area of IP, particularly its attempts to promote its own regulatory model for the protection of IP rights through trade agreements. By looking at the IP enforcement provisions of such agreements, the article also examines how the divisive issues that are currently hindering the progress of negotiations at WTO level, including the demands from developing countries to maintain a degree of autonomy in the area of IP regulation as well as the need to balance IP protection with human rights protection, are being dealt with in recent EU FTAs.

Regulating Services Trade Agreements - A Comparative Analysis of Regulatory Disciplines Included in EU and US Free Trade Agreements

Developed countries, led by the EU and the US, have consistently called for ‘deeper integration’ over the course of the past three decades i.e., the convergence of ‘behind-the-border’ or domestic polices and rules such as services, competition, public procurement, intellectual property (“IP”) and so forth. Following the collapse of the Doha Development Round, the EU and the US have pursued this push for deeper integration by entering into deep and comprehensive free trade agreements (“DCFTAs”) that are comprehensive insofar as they are not limited to tariffs but extend to regulatory trade barriers. More recently, the EU and the US launched negotiations on a Transatlantic Trade and Investment Partnership (“TTIP”) and a Trade in Services Agreement (“TISA”), which put tackling barriers resulting from divergences in domestic regulation in the area of services at the very top of the agenda. Should these agreements come to pass, they may well set the template for the rules of international trade and define the core features of domestic services market regulation. This article examines the regulatory disciplines in the area of services included in existing EU and US DCFTAs from a comparative perspective in order to delineate possible similarities and divergences and assess the extent to which these DCFTAs can shed some light into the possible outcome and limitations of future trade negotiations in services. It also discusses the potential impact of such negotiations on developing countries and, more generally, on the multilateral process.

Multiuser Scheduling for Cognitive MIMO with Channel Estimation Errors and Feedback Delay

A multiuser scheduling multiple-input multiple-output (MIMO) cognitive radio network (CRN) with space-time block coding (STBC) is considered in this paper, where one secondary base station (BS) communicates with one secondary user (SU) selected from K candidates. The joint impact of imperfect channel state information (CSI) in BS → SUs and BS → PU due to channel estimation errors and feedback delay on the outage performance is firstly investigated. We obtain the exact outage probability expressions for the considered network under the peak interference power IP at PU and maximum transmit power Pm at BS which cover perfect/imperfect CSI scenarios in BS → SUs and BS → PU. In addition, asymptotic expressions of outage probability in high SNR region are also derived from which we obtain several important insights into the system design. For example, only with perfect CSIs in BS → SUs, i.e., without channel estimation errors and feedback delay, the multiuser diversity can be exploited. Finally, simulation results confirm the correctness of our analysis.

Discovery of Main-Belt Comet P/2006 VW139 by Pan-STARRS1

We describe the discovery of comet-like activity in main-belt asteroid (300163) 2006 VW139 (later re-designated as Comet P/2006 VW139) by Pan-STARRS1. We also detail follow-up photometric, spectroscopic, and dynamical analyses of the object.

Calibration of BAS-TR image plate response to high energy (3-300 MeV) carbon ions

The paper presents the calibration of Fuji BAS-TR image plate (IP) response to high energy carbon ions of different charge states by employing an intense laser-driven ion source, which allowed access to carbon energies up to 270 MeV. The calibration method consists of employing a Thomson parabola spectrometer to separate and spectrally resolve different ion species, and a slotted CR-39 solid state detector overlayed onto an image plate for an absolute calibration of the IP signal. An empirical response function was obtained which can be reasonably extrapolated to higher ion energies. The experimental data also show that the IP response is independent of ion charge states.

The dust environment of comet 67P/Churyumov-Gerasimenko from Rosetta OSIRIS and VLT observations in the 4.5 to 2.9 au heliocentric distance range inbound

Context. The ESA Rosetta spacecraft, currently orbiting around comet 67P/Churyumov-Gerasimenko, has already provided in situ measurements of the dust grain properties from several instruments,particularly OSIRIS and GIADA. We propose adding value to those measurements by combining them with ground-based observations of the dust tail to monitor the overall, time-dependent dust-production rate and size distribution.
Aims. To constrain the dust grain properties, we take Rosetta OSIRIS and GIADA results into account, and combine OSIRIS data during the approach phase (from late April to early June 2014) with a large data set of ground-based images that were acquired with the ESO Very Large Telescope (VLT) from February to November 2014.
Methods. A Monte Carlo dust tail code, which has already been used to characterise the dust environments of several comets and active asteroids, has been applied to retrieve the dust parameters. Key properties of the grains (density, velocity, and size distribution) were obtained from Rosetta observations: these parameters were used as input of the code to considerably reduce the number of free parameters. In this way, the overall dust mass-loss rate and its dependence on the heliocentric distance could be obtained accurately.
Results. The dust parameters derived from the inner coma measurements by OSIRIS and GIADA and from distant imaging using VLT data are consistent, except for the power index of the size-distribution function, which is α = −3, instead of α = −2, for grains smaller than 1 mm. This is possibly linked to the presence of fluffy aggregates in the coma. The onset of cometary activity occurs at approximately 4.3 AU, with a dust production rate of 0.5 kg/s, increasing up to 15 kg/s at 2.9 AU. This implies a dust-to-gas mass ratio varying between 3.8 and 6.5 for the best-fit model when combined with water-production rates from the MIRO experiment.

On the Privacy of Encrypted Skype Communications

The privacy of voice over IP (VoIP) systems is achieved by compressing and encrypting the sampled data. This paper investigates in detail the leakage of information from Skype, a widely used VoIP application. In this research, it has been demonstrated by using the dynamic time warping (DTW) algorithm, that sentences can be identified with an accuracy of 60%. The results can be further improved by choosing specific training data. An approach involving the Kalman filter is proposed to extract the kernel of all training signals.

The VINEYARD Approach: Versatile, Integrated, Accelerator-Based, Heterogeneous Data Centres.

Emerging web applications like cloud computing, Big Data and social networks have created the need for powerful centres hosting hundreds of thousands of servers. Currently, the data centres are based on general purpose processors that provide high flexibility buts lack the energy efficiency of customized accelerators. VINEYARD aims to develop an integrated platform for energy-efficient data centres based on new servers with novel, coarse-grain and fine-grain, programmable hardware accelerators. It will, also, build a high-level programming framework for allowing end-users to seamlessly utilize these accelerators in heterogeneous computing systems by employing typical data-centre programming frameworks (e.g. MapReduce, Storm, Spark, etc.). This programming framework will, further, allow the hardware accelerators to be swapped in and out of the heterogeneous infrastructure so as to offer high flexibility and energy efficiency. VINEYARD will foster the expansion of the soft-IP core industry, currently limited in the embedded systems, to the data-centre market. VINEYARD plans to demonstrate the advantages of its approach in three real use-cases (a) a bio-informatics application for high-accuracy brain modeling, (b) two critical financial applications, and (c) a big-data analysis application.

Problemas do desenvolvimento infantil e intervenção precoce

A Intervenção Precoce (IP) é hoje uma prática multidisciplinar que pro-­ cura responder às necessidades de crianças com perturbações do desen-­ volvimento e em situações de risco, ultrapassando os antigos modelos de estimulação precoce. O problema de decidir quais as crianças e famílias que devem ser apoiadas e as exigências do planejamento das intervenções acentuam a importância de um procedimento claro de caraterização, ou de diagnóstico, tanto das crianças como das situações. No modelo em que assenta a rede de intervenção precoce, de base local, implementada numa ampla região de Portugal, são enfatizadas as dimensões relacionais e contextuais do desenvolvimento e do risco. Dentro desta perspetiva, os autores têm procurado desenvolver práticas e instrumentos que permitam uma melhor elegibilidade dos casos e uma orientação técnica de intervenção mais focada nas efetivas necessidades da criança, da família e do contexto. São aqui apresentados os resultados da utilização da ODIP – Organização Diagnóstica em Intervenção Precoce – na caracterização das problemáticas de desenvolvimento e de risco de um total de 1.169 crianças e respetivos contextos.

Multilayer optimization in radio resource allocation for the packet transmission in wireless networks

Na última década tem-se assistido a um crescimento exponencial das redes de comunicações sem fios, nomeadamente no que se refere a taxa de penetração do serviço prestado e na implementação de novas infra-estruturas em todo o globo. É ponto assente neste momento que esta tendência irá não só continuar como se fortalecer devido à convergência que é esperada entre as redes móveis sem fio e a disponibilização de serviços de banda larga para a rede Internet fixa, numa evolução para um paradigma de uma arquitectura integrada e baseada em serviços e aplicações IP. Por este motivo, as comunicações móveis sem fios irão ter um papel fundamental no desenvolvimento da sociedade de informação a médio e longo prazos. A estratégia seguida no projecto e implementação das redes móveis celulares da actual geração (2G e 3G) foi a da estratificação da sua arquitectura protocolar numa estrutura modular em camadas estanques, onde cada camada do modelo é responsável pela implementação de um conjunto de funcionalidades. Neste modelo a comunicação dá-se apenas entre camadas adjacentes através de primitivas de comunicação pré-estabelecidas. Este modelo de arquitectura resulta numa mais fácil implementação e introdução de novas funcionalidades na rede. Entretanto, o facto das camadas inferiores do modelo protocolar não utilizarem informação disponibilizada pelas camadas superiores, e vice-versa acarreta uma degradação no desempenho do sistema. Este paradigma é particularmente importante quando sistemas de antenas múltiplas são implementados (sistemas MIMO). Sistemas de antenas múltiplas introduzem um grau adicional de liberdade no que respeita a atribuição de recursos rádio: o domínio espacial. Contrariamente a atribuição de recursos no domínio do tempo e da frequência, no domínio espacial os recursos rádio mapeados no domínio espacial não podem ser assumidos como sendo completamente ortogonais, devido a interferência resultante do facto de vários terminais transmitirem no mesmo canal e/ou slots temporais mas em feixes espaciais diferentes. Sendo assim, a disponibilidade de informação relativa ao estado dos recursos rádio às camadas superiores do modelo protocolar é de fundamental importância na satisfação dos critérios de qualidade de serviço exigidos. Uma forma eficiente de gestão dos recursos rádio exige a implementação de algoritmos de agendamento de pacotes de baixo grau de complexidade, que definem os níveis de prioridade no acesso a esses recursos por base dos utilizadores com base na informação disponibilizada quer pelas camadas inferiores quer pelas camadas superiores do modelo. Este novo paradigma de comunicação, designado por cross-layer resulta na maximização da capacidade de transporte de dados por parte do canal rádio móvel, bem como a satisfação dos requisitos de qualidade de serviço derivados a partir da camada de aplicação do modelo. Na sua elaboração, procurou-se que o standard IEEE 802.16e, conhecido por Mobile WiMAX respeitasse as especificações associadas aos sistemas móveis celulares de quarta geração. A arquitectura escalonável, o baixo custo de implementação e as elevadas taxas de transmissão de dados resultam num processo de multiplexagem de dados e valores baixos no atraso decorrente da transmissão de pacotes, os quais são atributos fundamentais para a disponibilização de serviços de banda larga. Da mesma forma a comunicação orientada à comutação de pacotes, inenente na camada de acesso ao meio, é totalmente compatível com as exigências em termos da qualidade de serviço dessas aplicações. Sendo assim, o Mobile WiMAX parece satisfazer os requisitos exigentes das redes móveis de quarta geração. Nesta tese procede-se à investigação, projecto e implementação de algoritmos de encaminhamento de pacotes tendo em vista a eficiente gestão do conjunto de recursos rádio nos domínios do tempo, frequência e espacial das redes móveis celulares, tendo como caso prático as redes móveis celulares suportadas no standard IEEE802.16e. Os algoritmos propostos combinam métricas provenientes da camada física bem como os requisitos de qualidade de serviço das camadas superiores, de acordo com a arquitectura de redes baseadas no paradigma do cross-layer. O desempenho desses algoritmos é analisado a partir de simulações efectuadas por um simulador de sistema, numa plataforma que implementa as camadas física e de acesso ao meio do standard IEEE802.16e.