32 research outputs found

    XRay: Enhancing the Web's Transparency with Differential Correlation

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    Today's Web services - such as Google, Amazon, and Facebook - leverage user data for varied purposes, including personalizing recommendations, targeting advertisements, and adjusting prices. At present, users have little insight into how their data is being used. Hence, they cannot make informed choices about the services they choose. To increase transparency, we developed XRay, the first fine-grained, robust, and scalable personal data tracking system for the Web. XRay predicts which data in an arbitrary Web account (such as emails, searches, or viewed products) is being used to target which outputs (such as ads, recommended products, or prices). XRay's core functions are service agnostic and easy to instantiate for new services, and they can track data within and across services. To make predictions independent of the audited service, XRay relies on the following insight: by comparing outputs from different accounts with similar, but not identical, subsets of data, one can pinpoint targeting through correlation. We show both theoretically, and through experiments on Gmail, Amazon, and YouTube, that XRay achieves high precision and recall by correlating data from a surprisingly small number of extra accounts.Comment: Extended version of a paper presented at the 23rd USENIX Security Symposium (USENIX Security 14

    PVA−DNA Cryogel Membranes: Characterization, Swelling, and Transport Studies

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    Double-stranded (ds) DNA from salmon testes has been incorporated into PVA hydrogels obtained by a technique of repeated freezing and thawing. The cryogels obtained are free of potential toxic species like chemical cross-linkers, and consequently, they can be used in pharmaceutical or medical applications. These cryogels show a good mechanical resistance and a white and opaque appearance caused by a heterogeneous porous structure. Encapsulated DNA molecules can be in a compacted or an extended conformation in the PVA matrix and can be controlled by tailoring the degree of crystallinity of the PVA network; this is supported by fluorescence microscopy and UV and FTIR spectroscopic studies. The two forms of encapsulated DNA were observed for different types of matrixes: an extended one in a more crystalline network and a globular one in a more amorphous one. Different associations of base pairs have also been observed. PVA cryogel crystallinity could be tailored by the cryogel contact with different salt solutions. Cryogel surface (scanning electron microscopy) and bulk morphology (porosimetry), swelling, DNA retention, and delivery kinetics have also been studied. All these investigations clearly show strong interactions between PVA and DNA

    Functional properties of sodium and calcium caseinate antimicrobial active films containing carvacrol

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    Active edible films were prepared by adding carvacrol into sodium caseinate (SC) and calcium caseinate (CC) matrices plasticized with two different glycerol concentrations (25 and 35 wt%) prepared by solvent casting. Functional characterisation of these bio-films was carried out by determination of some of their physico-chemical properties, such as colour, transparency, oxygen barrier, wettability, dye permeation properties and antibacterial effectiveness against Gram negative and Gram positive bacteria. All films exhibited good performance in terms of optical properties in the CIELab space showing high transparency. Carvacrol was able to reduce CC oxygen permeability and slightly increased the surface hydrophobicity. Dye diffusion experiments were performed to evaluate permeation properties. The diffusion of dye through films revealed that SC was more permeable than CC. The agar diffusion method was used for the evaluation of the films antimicrobial effectiveness against Escherichia cell and Staphylococcus aureus. Both SC and CC edible films with carvacrol showed inhibitory effects on both bacteria. (C) 2013 Elsevier Ltd. All rights reserved.This research was supported by the Ministry of Science and Innovation of Spain through the projects MAT2011-28468-C02-01, MAT2011-28468-C02-02 and HP2008-0080. M.P. Arrieta thanks Fundacion MAPFRE for "Ignacio Hernando de Larramendi 2009-Medio Ambiente" fellowship (MAPFRE-IHL-01). Authors thank Ferrer Alimentacion S.A., for providing the caseinates powders.Arrieta, MP.; Peltzer, MA.; López Martínez, J.; Garrigós Selva, MDC.; Valente, AJM.; Jimenez Migallon, A. (2014). Functional properties of sodium and calcium caseinate antimicrobial active films containing carvacrol. Journal of Food Engineering. 121:94-101. https://doi.org/10.1016/j.jfoodeng.2013.08.015S9410112

    Cryogels: Morphological, structural and adsorption characterisation

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    A permittivity study for PVA membranes, obtained by freeze-thaw technique

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    Late diffusion or selective diffusion through polymeric membranes has various applications in separation processes, environmental protection, pharmaceutics for drug delivery systems, etc. The aim of this work is to present the results of some ions diffusion through poly(vinyl alcohol) [PVA] hydrogel membranes, obtained by freeze-thaw technique. The diffusion of potentially toxic ions -Pb(II)- and of alkaline ions like Na+ and K+ is tested using conductometry, flame photometry and atomic absorption spectrometry. The membrane permitivitty is calculated for every ionic species and the opportunity is studied to use these membranes in environmental protection, for waste water purification. The modifications of the PVA structure have been made by mixing the PVA solution with some natural products (beta-cyclodextrine or chitosan) or by compounding PVA hydrogel with Cu2+

    Hemoperitoneum as a Life-Threatening Complication of an Acute Cholecystitis in a Patient with Hemophilia A with Inhibitors: A Case Report

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    We present the case of a 52-year-old male with severe hemophilia A with inhibitors, who was diagnosticated with acute lithiasic cholecystitis that required surgical intervention due to lack of favorable response to conservatory treatment. During surgery, hemostatic support was performed with activated recombinant factor VII (rFVIIa, NovoSeven®). The surgery was performed first laparoscopically with adhesiolysis, followed by subcostal laparotomy and cholecystectomy because of the findings of a pericholecystic plastron with abscess and massive inflammatory anatomical modifications. The patient presented postoperative complications, requiring a second surgical intervention, due to the installation of a hemoperitoneum. Hemostatic treatment with rFVIIa was given for a further 3 weeks postoperatively, and the patient was discharged in safe condition. A surgical intervention increases the risk of bleeding in hemophilic patients, which may have vital complications in the absence of adequate hemostatic support and the support of a multidisciplinary team with experience in hemophilic surgery
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