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11.
Ambrosio Toval Joaquín Nicolás Begoña Moros Fernando García 《Requirements Engineering》2002,6(4):205-219
Information systems security issues have usually been considered only after the system has been developed completely, and
rarely during its design, coding, testing or deployment. However, the advisability of considering security from the very beginning
of the system development has recently begun to be appreciated, and in particular in the system requirements specification
phase. We present a practical method to elicit and specify the system and software requirements, including a repository containing
reusable requirements, a spiral process model, and a set of requirements documents templates. In this paper, this method is
focused on the security of information systems and, thus, the reusable requirements repository contains all the requirements
taken from MAGERIT, the Spanish public administration risk analysis and management method, which conforms to ISO 15408, Common
Criteria Framework. Any information system including these security requirements must therefore pass a risk analysis and management
study performed with MAGERIT. The requirements specification templates are hierarchically structured and are based on IEEE
standards. Finally, we show a case study in a system of our regional administration aimed at managing state subsidies. 相似文献
12.
Hernández-Santos D Díaz-González M González-García MB Costa-García A 《Analytical chemistry》2004,76(23):6887-6893
Voltammetric enzyme genosensors on streptavidin-modified screen-printed carbon electrodes (SPCEs) for the detection of virulence nucleic acid determinants of pneumolysin and autolysin genes, exclusively present on the genome of the human pathogen Streptococcus pneumoniae, were described. Alkaline phosphatase (AP) and 3-indoxyl phosphate were used as the enzymatic label and substrate, respectively. The oligonucleotide probes were immobilized on electrochemically pretreated SPCEs through the streptavidin/biotin reaction. The adsorption of streptavidin was performed by deposition of a drop of a streptavidin solution overnight at 4 degrees C on the surface of the SPCEs. After the hybridization reaction with FITC-labeled complementary targets, the enzyme is captured using an anti-FITC antibody conjugated to AP. In nonstringent experimental conditions, these genosensors can detect 0.49 fmol of 20-mer oligonucleotide target and discriminate between a complementary oligo and an oligo with a three-base mismatch. In the presence of 25% formamide in the hybridization buffer, a single-base mismatch on the oligonucleotide target can be detected. 相似文献
13.
The colloidal approach has been studied as an essential step in the tailoring of ceramic nanostructures, but most colloidal processes are limited by the complexity of preparation of highly concentrated and stable suspensions of nanoparticles and their fast ageing. Electrophoretic deposition (EPD) stands out as the most appropriate colloidal process to produce ceramic structures using low solid content sols and suspensions (<1 g/l). This characteristic drastically increases its range of technological applicability to nanoparticle assembly, becoming an alternative to the evaporative coating processes. Modelling of this direct electrically driven assembly process is key for its application to the performance of new materials on length scales of approximately 1–100 nm. In this paper, the key contributions in this field to process control and development of the electrophoretic kinetics equation are summarised. 相似文献
14.
Juana Bernabé Juana Mulero Begoña Cerdá Cristina García-Viguera Diego A. Moreno Soledad Parra Francisco Avilés Angel Gil-Izquierdo José Abellán Pilar Zafrilla 《Journal of Functional Foods》2013,5(3):1031-1038
Bioactive substances found in numerous foods can be successfully and safely used to modify various cellular functions and affect the oxidative stress. The aim of this study was to analyze the effect of a citrus-based juice (juice citrus (95%) with 5% of aronia extract (Aronia melanocarpa)) on biomarkers of oxidative stress in patients with metabolic syndrome compared with healthy individuals. The study comprised 20 healthy subjects and 33 patients with metabolic syndrome. Eighteen patients consumed daily 300 mL of a citrus-based juice during 6 months and 15 patients consumed 300 mL of a placebo beverage. The control group consumed a citrus-based juice (CJ). Before, and at sixth months after consuming of a citrus-based juice the following parameters were determined: 15-isoprostane F2, 8-hydroxydeoxyguanosine (8-OHdG), reduced and oxidized glutathione (GSH/GSSH), carbonyl groups and oxidized LDL (ox-LDL). After consuming CJ during 6 months the values of 8-OHdG, carbonyl groups and LDL-ox decreased in both analyzed groups and the values of GSH/GSSH increased. Significant differences were observed in both groups. Thus consumption of citrus-based juice improved the biomarkers of oxidative stress in metabolic syndrome patients. 相似文献
15.
Carlos Sáenz Begoña Hernández Coro Alberdi Santiago Alfonso José Manuel Diñeiro 《European Food Research and Technology》2008,227(5):1329-1338
We have designed a multispectral imaging acquisition system to measure the relative concentration values of myoglobin forms
inside meat during oxygenation. Images at 474, 525, 572 and 610 nm are used to compute the concentration of reduced myoglobin,
oxymyoglobin and metmyoglobin with a spatial resolution of 0.0125 mm/pixel. From these images, pigment concentration profiles
as a function of oxygenation time and depth beneath the surface were obtained. A model describing the diffusion of oxygen
and the consumption of reduced myoglobin is numerically tested versus the measured concentration profiles. The model accurately
fits the data with a Mean Root Squared Error equal to 0.253%. Precise definitions for position and width of pigment layers
based in concentration profiles are given. The results suggest that multispectral imaging techniques combined with precise
control and measurement of sample temperature and oxygen partial pressure will permit detailed studies of the myoglobin chemistry
during oxygenation. 相似文献
16.
17.
The effects of fatty acid composition, two packaging methods (vacuum and 20% CO2/80% N2) and storage under refrigeration for 210 days were evaluated on a dry fermented sausage (salchichón), manufactured with raw material enriched in monounsaturated or polyunsaturated fatty acids. Fatty acid composition was determined on sausage mixtures and on ripened sausages and lipid oxidation and colour stability was determined on ripened sausage at different times during storage. The modification of fatty acid composition of the sausages raised the nutritional quality, slightly affecting the colour properties. Dry fermented sausages enriched in polyunsaturated and monounsaturated fatty acids presented higher lipid oxidation values than the control ones. Both packaging methods (vacuum and 20% CO2/80% N2) during 210 days of chilled storage had minor effects on the colour and the lipid oxidation stability. 相似文献
18.
Nanomedicine: Silver Atomic Quantum Clusters of Three Atoms for Cancer Therapy: Targeting Chromatin Compaction to Increase the Therapeutic Index of Chemotherapy (Adv. Mater. 33/2018) 下载免费PDF全文
Vanesa Porto Erea Borrajo David Buceta Carmen Carneiro Shahana Huseyinova Blanca Domínguez Kyra J. E. Borgman Melike Lakadamyali Maria F. Garcia‐Parajo José Neissa Tomás García‐Caballero Giampaolo Barone M. Carmen Blanco Natalia Busto Begoña García José Maria Leal José Blanco José Rivas M. Arturo López‐Quintela Fernando Domínguez 《Advanced materials (Deerfield Beach, Fla.)》2018,30(33)
19.
Salvador P Artíñano B Querol X Alastuey A 《The Science of the total environment》2008,390(2-3):495-506
This study has investigated the influence of synoptic weather patterns and long-range transport episodes on the concentration levels of airborne particulate matter (TSP, PM10 and PM2.5) and some major ions (SO(4)(2-), NO(3)(-) and NH(4)(+)) at a background rural station in central Spain. Air mass back-trajectories arriving at the site in 1999-2005 have been analysed by statistical methods. First, cluster analysis was used to group trajectories into 8 clusters depending on their direction and speed. Meteorological scenarios associated to each cluster have been obtained and interpreted. Then, the incidence of different air mass transport patterns on particle concentrations and composition recorded at this station was evaluated. This evaluation included PM10 and PM2.5 concentrations and chemical composition data, obtained at three representative sites of the Madrid air basin during sampling campaigns carried out in the course of the 1999-2005 period. Finally, a residence time analysis of trajectories was also performed to detect remote sources and transport pathways. Significantly elevated concentrations of TSP and PM10 were observed for Northern African flows as a consequence of the transport of mineral dust. Significant inter-cluster differences were also observed for PM2.5 and secondary inorganic compounds, with the highest concentrations associated with low baric gradient situations and Southern European flows. The residence time analysis confirmed that current TSP and PM10 concentrations in central Spain are likely to be influenced significantly by long-range transport of desert dust from different desert regions in North Africa. Furthermore, emissions from continental Europe with a high time of residence in the western and central areas of the Mediterranean basin, seem to significantly influence PM2.5 and secondary inorganic aerosol concentrations in this region. 相似文献
20.
Fanjul-Bolado P Hernández-Santos D González-García MB Costa-García A 《Analytical chemistry》2007,79(14):5272-5277
Alkaline phosphatase (AP) is one of the most used enzymatic labels for the development of ELISAs, immunosensors, DNA hybridization assays, etc. This enzyme catalyzes the dephosphorylation of a substrate into a detectable product usually quantified by optical or electrochemical measurements. This work is based on a substrate (3-indoxyl phosphate) that produces a compound able to reduce silver ions in solution into a metallic deposit, which is localized where the enzymatic label AP is attached. The deposited silver is electrochemically stripped into solution and measured by anodic stripping voltammetry. Its application to an enzymatic genosensor on streptavidin-modified screen-printed carbon electrodes for the detection of virulence nucleic acid determinants of autolysin gene, exclusively present on the genome of the human pathogen Streptococcus pneumoniae, is described. Compared with the direct voltammetric detection of indigo carmine, the anodic stripping voltammetry of silver ions is 14-fold more sensitive. 相似文献