55 research outputs found

    Sistema de reconocimiento biométrico en ambientes de alta seguridad

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    En esta tesina se han analizado e implementado tres algoritmos existentes para el reconocimiento biométrico de personas por medio del iris. Los mismos fueron evaluados con diferentes bases de imágenes preexistentes, utilizadas habitualmente para evaluar y comparar este tipo de algoritmos. A partir de los resultados obtenidos, se realizaron mejoras sobre cada uno de ellos, buscando siempre la mejor implementación orientada a ambientes de seguridad. Esto derivó en el desarrollo de un algoritmo final, que considera las mejores cualidades de los tres algoritmos implementados y sus respectivas mejoras. Para su evaluación, de las bases de imágenes seleccionadas, se ha elegido aquella con características cercanas a las que se pueden presentar en un ambiente de alta seguridad, como las instituciones penitenciarias. Los resultados obtenidos por la implementación final son cercanos al óptimo y muestran claramente el nivel de desempeño y fiabilidad de este tipo de sistemas de reconocimiento biométrico.Facultad de Informátic

    Reviewing Traffic ClassificationData Traffic Monitoring and Analysis

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    Traffic classification has received increasing attention in the last years. It aims at offering the ability to automatically recognize the application that has generated a given stream of packets from the direct and passive observation of the individual packets, or stream of packets, flowing in the network. This ability is instrumental to a number of activities that are of extreme interest to carriers, Internet service providers and network administrators in general. Indeed, traffic classification is the basic block that is required to enable any traffic management operations, from differentiating traffic pricing and treatment (e.g., policing, shaping, etc.), to security operations (e.g., firewalling, filtering, anomaly detection, etc.). Up to few years ago, almost any Internet application was using well-known transport layer protocol ports that easily allowed its identification. More recently, the number of applications using random or non-standard ports has dramatically increased (e.g. Skype, BitTorrent, VPNs, etc.). Moreover, often network applications are configured to use well-known protocol ports assigned to other applications (e.g. TCP port 80 originally reserved for Web traffic) attempting to disguise their presence. For these reasons, and for the importance of correctly classifying traffic flows, novel approaches based respectively on packet inspection, statistical and machine learning techniques, and behavioral methods have been investigated and are becoming standard practice. In this chapter, we discuss the main trend in the field of traffic classification and we describe some of the main proposals of the research community. We complete this chapter by developing two examples of behavioral classifiers: both use supervised machine learning algorithms for classifications, but each is based on different features to describe the traffic. After presenting them, we compare their performance using a large dataset, showing the benefits and drawback of each approac

    Differential protection by cell wall components of Lactobacillus amylovorus DSM 16698T against alterations of membrane barrier and NF-kB activation induced by enterotoxigenic F4+ Escherichia coli on intestinal cells

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    Background: The role of Lactobacillus cell wall components in the protection against pathogen infection in the gut is still largely unexplored. We have previously shown that L. amylovorus DSM 16698(T) is able to reduce the enterotoxigenic F4(+)Escherichia coli (ETEC) adhesion and prevent the pathogen-induced membrane barrier disruption through the regulation of IL-10 and IL-8 expression in intestinal cells. We have also demonstrated that L. amylovorus DSM 16698T protects host cells through the inhibition of NF-kB signaling. In the present study, we investigated the role of L. amylovorus DSM 16698(T) cell wall components in the protection against F4(+)ETEC infection using the intestinal Caco-2 cell line. Methods: Purified cell wall fragments (CWF) from L. amylovorus DSM 16698T were used either as such (uncoated, U-CWF) or coated with S-layer proteins (S-CWF). Differentiated Caco-2/TC7 cells on Transwell filters were infected with F4(+)ETEC, treated with S-CWF or U-CWF, co-treated with S-CWF or U-CWF and F4(+)ETEC for 2.5 h, or pre-treated with S-CWF or U-CWF for 1 h before F4(+)ETEC addition. Tight junction (TJ) and adherens junction (AJ) proteins were analyzed by immunofluorescence and Western blot. Membrane permeability was determined by phenol red passage. Phosphorylated p65-NF-kB was measured by Western blot. Results: We showed that both the pre-treatment with S-CWF and the co- treatment of S-CWF with the pathogen protected the cells from F4(+)ETEC induced TJ and AJ injury, increased membrane permeability and activation of NF-kB expression. Moreover, the U-CWF pre-treatment, but not the co- treatment with F4(+)ETEC, inhibited membrane damage and prevented NF-kB activation. Conclusions: The results indicate that the various components of L. amylovorus DSM 16698(T) cell wall may counteract the damage caused by F4(+)ETEC through different mechanisms. S-layer proteins are essential for maintaining membrane barrier function and for mounting an anti-inflammatory response against F4(+)ETEC infection. U-CWF are not able to defend the cells when they are infected with F4(+)ETEC but may activate protective mechanisms before pathogen infection.Peer reviewe

    Immune System, Gut Microbiota and Diet: An Interesting and Emerging Trialogue

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    The present chapter provides a comprehensive overview of the multifaceted links connecting the immune system, the intestinal microbiota, and the diet, covering also some recent, less explored, and emerging topics such as the “trained immunity” and the immune cell metabolic activity. The main characteristics of the innate and adaptive immune system are described, as well as the gut-associated lymphoid tissue (GALT). Gut microbiota structure and function are also presented. Particular emphasis is given to the diet as a modulator of the microbiota-immune system crosstalk, focusing on the impact of the three main dietary components (carbohydrates, proteins, and fats) and the different dietary profiles on the gut microbiota, by shaping its composition and the deriving microbial metabolites that influence host health, also through interaction with the immune system. Western and Mediterranean diets are described and chosen as representative models of detrimental and beneficial dietary patterns, respectively

    Chemical composition and biological activities of essential oils from Origanum vulgare genotypes belonging to the carvacrol and thymol chemotypes

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    The remarkable biological activities of oregano essential oils (EOs) have recently prompted a host of studies aimed at exploring their potential innovative applications in the food and pharmaceutical industries. The chemical composition and biological activities of EOs from two Origanum vulgare genotypes, widely cultivated in Sicily and not previously studied for their biological properties, were characterized. Plants of the two genotypes, belonging to the carvacrol (CAR) and thymol (THY) chemotypes and grown in different cultivation environments, were considered for this study. The chemical profiles, including the determination of enantiomeric distribution, of the EOs, obtained by hydrodistillation from dried leaves and flowers, were investigated by GC-MS. Biological activity was evaluated as antimicrobial properties against different pathogen indicator strains, while intestinal barrier integrity, reduction in pathogen adhesion and anti-inflammatory actions were assayed in the intestinal Caco-2 cell line. The chemical profile of the CAR genotype was less complex and characterized by higher levels of the most active compound, i.e., carvacrol, when compared to the THY genotype. The enantiomeric distribution of chiral constituents did not vary across genotypes, while being markedly different from that observed in Origanum vulgare genotypes from other geographical origins. In general, all EOs showed high antimicrobial activity, both in vitro and in a food matrix challenge test. Representative EOs from the two genotypes resulted not altering epithelial monolayer sealing only for concentrations lower than 0.02%, were able to reduce the adhesion of selected pathogens, but did not exert relevant anti-inflammatory effects. These results suggest their potential use as control agents against a wide spectrum of foodborne pathogens

    Reconocimiento biométrico de iris en ambientes de alta seguridad

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    En este trabajo se presenta el uso de identificación biométrica por medio del reconocimiento de iris, en ambientes específicos que requieran alto nivel de seguridad, como por ejemplo las penitenciarías. Se analizan diferentes algoritmos existentes tales como Extraction of Complex Wavelet Features for Iris Recognition (CWF), DCT-Based Iris Recognition (DCT) e Iris recognition Based on Multichanel Gabor Filtering (MGF), con el objetivo de compararlos y determinar su adaptabilidad a estos entornos. La elección de estos tres algoritmos se debe a los buenos resultados presentados por ellos tanto en la identificación como en la verificación de identidad. A partir de las características más relevantes de los algoritmos analizados se presenta el desarrollo de un sistema de identificación para utilizar en el ámbito antes mencionado. Para determinar el comportamiento del sistema se comparan los resultados obtenidos con los analizados previamente. Los resultados logrados permiten indicar que la implementación propuesta tiene un muy buen funcionamiento al trabajar con imágenes que poseen las mismas características que las que se pueden obtener en el ambiente requerido.Eje: Workshop Computación gráfica, imágenes y visualización (WCGIV)Red de Universidades con Carreras en Informática (RedUNCI

    Peri-operative red blood cell transfusion in neonates and infants: NEonate and Children audiT of Anaesthesia pRactice IN Europe: A prospective European multicentre observational study

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    BACKGROUND: Little is known about current clinical practice concerning peri-operative red blood cell transfusion in neonates and small infants. Guidelines suggest transfusions based on haemoglobin thresholds ranging from 8.5 to 12 g dl-1, distinguishing between children from birth to day 7 (week 1), from day 8 to day 14 (week 2) or from day 15 (≥week 3) onwards. OBJECTIVE: To observe peri-operative red blood cell transfusion practice according to guidelines in relation to patient outcome. DESIGN: A multicentre observational study. SETTING: The NEonate-Children sTudy of Anaesthesia pRactice IN Europe (NECTARINE) trial recruited patients up to 60 weeks' postmenstrual age undergoing anaesthesia for surgical or diagnostic procedures from 165 centres in 31 European countries between March 2016 and January 2017. PATIENTS: The data included 5609 patients undergoing 6542 procedures. Inclusion criteria was a peri-operative red blood cell transfusion. MAIN OUTCOME MEASURES: The primary endpoint was the haemoglobin level triggering a transfusion for neonates in week 1, week 2 and week 3. Secondary endpoints were transfusion volumes, 'delta haemoglobin' (preprocedure - transfusion-triggering) and 30-day and 90-day morbidity and mortality. RESULTS: Peri-operative red blood cell transfusions were recorded during 447 procedures (6.9%). The median haemoglobin levels triggering a transfusion were 9.6 [IQR 8.7 to 10.9] g dl-1 for neonates in week 1, 9.6 [7.7 to 10.4] g dl-1 in week 2 and 8.0 [7.3 to 9.0] g dl-1 in week 3. The median transfusion volume was 17.1 [11.1 to 26.4] ml kg-1 with a median delta haemoglobin of 1.8 [0.0 to 3.6] g dl-1. Thirty-day morbidity was 47.8% with an overall mortality of 11.3%. CONCLUSIONS: Results indicate lower transfusion-triggering haemoglobin thresholds in clinical practice than suggested by current guidelines. The high morbidity and mortality of this NECTARINE sub-cohort calls for investigative action and evidence-based guidelines addressing peri-operative red blood cell transfusions strategies. TRIAL REGISTRATION: ClinicalTrials.gov, identifier: NCT02350348

    Sportsmen’s Attitude towards Dietary Supplements and Nutrition Knowledge: An Investigation in Selected Roman Area Gyms

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    The non-professional sport environment is a grey zone not as widely assessed as that of elite athletes. The purpose of this research was to investigate the dietary supplementation habits and the nutrition knowledge on sport (NKS) in a sample of gym users. The level of adequacy of NKS was set at ≥60% of correct answers. Almost half (46.4%) of respondents stated they used food supplements, in particular multivitamins (31.0%), amino acid pills (29.5%), minerals (29.1%), and protein powders (28.7%). Supplements were used to increase muscle mass (36.9%) and to repair muscle (35.1%). Gym trainers were the preferred source of information on the use of supplements, especially in males (84%). The NKS correct response rate was 57.1% and the proportion of respondents with a sufficient level of NKS was 47.3%. The prevalence of correct answers was highest in males (61.5%) and for respondents with the highest educational attainment levels (44.5% and 53%). This study demonstrated that non-professional sportsmen do not have sufficient knowledge of nutrition and that the gym environment does not facilitate the circulation of the correct information on the role of supplementation. Considering the importance of nutrition for sportsmen, it is necessary to put in place actions aimed at increasing the knowledge of nutrition of gym users and their trainers
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