A distributed admission control model for CoS networks using QoS and SLS monitoring

Achieving an admission control strategy for CoS networks covering both intra-domain and end-to-end operation is still an open issue. This paper discusses how AC can be carried out without adding significant complexity to the network control plane and proposes a distributed service-oriented AC model for these networks. The model only involves the network edge nodes leaving the network core unchanged. Ingress nodes perform implicit or explicit service-dependent AC based on both QoS and SLSs utilization metrics, obtained through on-line edge-to-edge monitoring performed at egress nodes. From an end-to-end perspective, the flow request is used both for AC and available service computation. Relevant aspects of the model interrelated areas and implementation key points are also discussed

Managing services quality through admission control and active monitoring

We propose a lightweight traffic admission control scheme based on on-line monitoring which ensures multimedia services quality both intra-domain and end-to-end. The AC strategy is distributed, service-oriented and allows to control QoS and SLS without adding complexity to the network core. For each service class, AC decisions are driven by rate-based SLS control rules and QoS parameters control rules, defined and parameterized according to each service characteristics. These rules are essentially based on systematic on-line measurements of relevant QoS and performance parameters. Thus, from a practical perspective, we discuss and evaluate methodologies and mechanisms for parameter estimation. The AC criteria is evaluated as regards its ability to ensure service commitments while achieving high network utilization. The results show that the proposed model provides a good compromise between simplicity, service level guarantee and network usage, even for services with strict QoS requirements

A distributed admission control model for class-based networks using edge-toedge QoS and SLS monitoring

The advent of class-based networks has brought new needs for network traffic control in order to assure a certain QoS level. Despite the existing proposals, achieving a generic admission control (AC) strategy for traffic entering these networks is still an open issue. This paper provides new insights on how AC shall be accomplished proposing an encompassing AC model for multi-service class-based networks, which covers both intra-domain and end-to-end operation, without requiring changes in the network core and complex AC signaling. For each service type, AC is distributed and based on both on-line edge-to-edge monitoring of relevant QoS parameters and SLSs utilization. Service monitoring, performed at egress nodes, provides adequate metrics to ingress nodes which take implicit or explicit AC decisions based on service-dependent criteria. Although being oriented to flow AC, the model can easily be applied to SLS AC. SLS auditing and SLS traffic conditioning are tasks also covered

Moire bands in twisted double-layer graphene

A moire pattern is formed when two copies of a periodic pattern are overlaid with a relative twist. We address the electronic structure of a twisted two-layer graphene system, showing that in its continuum Dirac model the moire pattern periodicity leads to moire Bloch bands. The two layers become more strongly coupled and the Dirac velocity crosses zero several times as the twist angle is reduced. For a discrete set of magic angles the velocity vanishes, the lowest moire band flattens, and the Dirac-point density-of-states and the counterflow conductivity are strongly enhanced

The visitor from an ancient galaxy: A planetary companion around an old, metal-poor red horizontal branch star

We report the detection of a planetary companion around HIP 13044, a metal-poor red horizontal branch star belonging to a stellar halo stream that results from the disruption of an ancient Milky Way satellite galaxy. The detection is based on radial velocity observations with FEROS at the 2.2-m MPG/ESO telescope. The periodic radial velocity variation of P=16.2 days can be distinguished from the periods of the stellar activity indicators. We computed a minimum planetary mass of 1.25 Jupiter masses and an orbital semimajor axis of 0.116 AU for the planet. This discovery is unique in three aspects: First, it is the first planet detection around a star with a metallicity much lower than few percent of the solar value; second, the planet host star resides in a stellar evolutionary stage that is still unexplored in the exoplanet surveys; third, the planetary system HIP 13044 most likely has an extragalactic origin in a disrupted former satellite of the Milky Way.Comment: 5 pages, 2 figures, 2 tables, submitted to the Proceedings of the 276th IAU Symposium "The Astrophysics of Planetary Systems

Dairy products and inflammation: a review of the clinical evidence

Inflammation is a major biological process regulating the interaction between organisms and the environment, including the diet. Because of the increase in chronic inflammatory diseases, and in light of the immune-regulatory properties of breastfeeding, the ability of dairy products to modulate inflammatory processes in humans is an important but unresolved issue. Here, we report a systematic review of 52 clinical trials investigating inflammatory markers in relation to the consumption of dairy products. An inflammatory score (IS) was defined to quantitatively evaluate this interaction. The IS was significantly positive for the entire data set, indicating an anti-inflammatory activity in humans. When the subjects were stratified according to their health status, the IS was strongly indicative of an anti-inflammatory activity in subjects with metabolic disorders and of a pro-inflammatory activity in subjects allergic to bovine milk. Stratifying the data by product categories associated both low-fat and high-fat products, as well as fermented products, with an anti-inflammatory activity. Remarkably, the literature is characterized by a large gap in knowledge on bioavailability of bioactive nutrients. Future research should thus better combine food and nutritional sciences to adequately follow the fate of these nutrients along the gastrointestinal and metabolic axes.info:eu-repo/semantics/publishedVersio

Using zeta-potential measurements to quantify peptide partition to lipid membranes

© The Author(s) 2011. This article is published with open access at Springerlink.com.Open Access: This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.Many cellular phenomena occur on the biomembranes. There are plenty of molecules (natural or xenobiotics) that interact directly or partially with the cell membrane. Biomolecules, such as several peptides (e.g., antimicrobial peptides) and proteins, exert their effects at the cell membrane level. This feature makes necessary investigating their interactions with lipids to clarify their mechanisms of action and side effects necessary. The determination of molecular lipid/water partition constants (Kp) is frequently used to quantify the extension of the interaction. The determination of this parameter has been achieved by using different methodologies, such as UV-Vis absorption spectrophotometry, fluorescence spectroscopy and ζ-potential measurements. In this work, we derived and tested a mathematical model to determine the Kp from ζ-potential data. The values obtained with this method were compared with those obtained by fluorescence spectroscopy, which is a regular technique used to quantify the interaction of intrinsically fluorescent peptides with selected biomembrane model systems. Two antimicrobial peptides (BP100 and pepR) were evaluated by this new method. The results obtained by this new methodology show that ζ-potential is a powerful technique to quantify peptide/lipid interactions of a wide variety of charged molecules, overcoming some of the limitations inherent to other techniques, such as the need for fluorescent labeling.This work was partially supported by project PTDC/QUI/ 69937/2006 from Fundação para a Ciência e Tecnologia-Ministério da Ciência, Tecnologia e Ensino Superior (FCT-MCTES, Portugal), and by Fundação Calouste Gulbenkian (Portugal). JMF and MMD also thank FCT-MCTES for grants IMM/BT/37-2010 and SFRH/BD/41750/2007, respectively

Vulnerability: possible uses of a philosophical, legal, political and social concept

Nowadays, in the discourse of the social, legal, political and philosophical sciences, the term "vulnerability" is used more and more frequently with different, and sometimes even contradictory, meanings. This is even truer when political consequences are drawn from the definition of certain individuals or social groups as "vulnerable". In particular, one cannot forget that the term "vulnerability" assumes a stigmatizing and disciplining character when used in risk management studies in contemporary social policy, where the objective is the identification of the "most vulnerable" social groups, in order to adopt standardized assessment strategies and to implement measures aimed at limiting social costs through the creation of resilient individuals able to find first of all in themselves, thanks to the techniques of behaviorist psychology, the resources to reduce their "vulnerability". In the legal field, the category of "vulnerable subjects" or "weak subjects" appears in various sectors - criminal procedure, labor law, administrative law, etc. It is used to identify groups of people that supposedly require particular rules, procedures, and practices, because of their alleged "weakness". Many are the groups qualified by law as "weak" or "vulnerable". Within them there are people with very different characteristics, such as women, children, the disabled, and victims of violence. From the legal point of view these categorizations raise acute concern, because they involve directly fundamental legal concepts such as autonomy, equality, and self-determination. Given the extensive use of the "vulnerability" rhetoric in a wide range of disciplinary fields, it is important to understand and compare the most common conceptions of “vulnerability” in philosophical, legal, political and social language. This analysis will lead to a re-signification of the term, in order to separate the notion of "vulnerability" from stereotypes that tend to paint the socalled “vulnerable groups” or “vulnerable subjects” as victims. Framed in these terms, the term "vulnerability" opens up the possibility of a fruitful dialogue between theory and activism of historically marginalized and disadvantaged social groups, who are among the first to bear the costs of the austerity and welfare cuts of contemporary neoliberal policies, but who are also often the first to challenge their own qualification as "vulnerable". This edition has papers organized in three special sections about vulnerability: 1) The philosophical perspectives; 2) the philosophical - juridical debates; 3) the sociological perspectives

Channeling anabolic side-products towards the production of non-essential metabolites: stable malate production in Synechocystis sp. PCC6803

[Image: see text] Powered by (sun)light to oxidize water, cyanobacteria can directly convert atmospheric CO(2) into valuable carbon-based compounds and meanwhile release O(2) to the atmosphere. As such, cyanobacteria are promising candidates to be developed as microbial cell factories for the production of chemicals. Nevertheless, similar to other microbial cell factories, engineered cyanobacteria may suffer from production instability. The alignment of product formation with microbial fitness is a valid strategy to tackle this issue. We have described previously the “FRUITS” algorithm for the identification of metabolites suitable to be coupled to growth (i.e., side products in anabolic reactions) in the model cyanobacterium Synechocystis. sp PCC6803. However, the list of candidate metabolites identified using this algorithm can be somewhat limiting, due to the inherent structure of metabolic networks. Here, we aim at broadening the spectrum of candidate compounds beyond the ones predicted by FRUITS, through the conversion of a growth-coupled metabolite to downstream metabolites via thermodynamically favored conversions. We showcase the feasibility of this approach for malate production using fumarate as the growth-coupled substrate in Synechocystis mutants. A final titer of ∼1.2 mM was achieved for malate during photoautotrophic batch cultivations. Under prolonged continuous cultivation, the most efficient malate-producing strain can maintain its productivity for at least 45 generations, sharply contrasting with other producing Synechocystis strains engineered with classical approaches. Our study also opens a new possibility for extending the stable production concept to derivatives of growth-coupled metabolites, increasing the list of suitable target compounds

RNA:DNA ratios as a proxy of egg production rates of Acartia

Estimates of copepod secondary production are of great importance to infer the global organic matter fluxes in aquatic ecosystems and species-specific responses of zooplankton to hydrologic variability. However, there is still no routine method to determine copepods secondary production in order to eliminate time consuming experimental analyses. Therefore, we determined whether there is a correlation between Egg Production Rates (EPR) and RNA:DNA ratios of Acartia species, by measuring their seasonal and spatial variability and the influence of environmental factors for Acartia sp. collected in the Guadiana river estuary. EPR of Acartia tonsa was positively related with chlorophyll a concentration, freshwater inflow and biomass of dinoflagellates, while Acartia clausi was only related to dinoflagellates. Dinoflagellates seem to be the optimal food item influencing the reproduction of both Acartia species in the studied area. The biochemical index RNA:DNA was positively related to EPR, indicating that it is a good proxy of copepod production and a promising method to use in the future to estimate secondary production. (C) 2017 Elsevier Ltd. All rights reserved.Portuguese Foundation for Science and Technology (FCT) [SFRH/BD/28198/2006]FCT [SFRH/BSAB/113684/2015, SFRH/BPD/105419/2014, IF/01546/2015]FTC [UID/Multi/04326/2013]info:eu-repo/semantics/publishedVersio