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71.
In this paper, we introduce a new access control model that aims at addressing the privacy implications surrounding network monitoring. In fact, despite its importance, network monitoring is natively leakage-prone and, moreover, this is exacerbated due to the complexity of the highly dynamic monitoring procedures and infrastructures, that may include multiple traffic observation points, distributed mitigation mechanisms and even inter-operator cooperation. Conceived on the basis of data protection legislation, the proposed approach is grounded on a rich in expressiveness information model, that captures all the underlying monitoring concepts along with their associations. The model enables the specification of contextual authorisation policies and expressive separation and binding of duty constraints. Finally, two key innovations of our work consist in the ability to define access control rules at any level of abstraction and in enabling a verification procedure, which results in inherently privacy-aware workflows, thus fostering the realisation of the Privacy by Design vision.  相似文献   
72.
Image-based modeling of tumor growth combines methods from cancer simulation and medical imaging. In this context, we present a novel approach to adapt a healthy brain atlas to MR images of tumor patients. In order to establish correspondence between a healthy atlas and a pathologic patient image, tumor growth modeling in combination with registration algorithms is employed. In a first step, the tumor is grown in the atlas based on a new multiscale, multiphysics model including growth simulation from the cellular level up to the biomechanical level, accounting for cell proliferation and tissue deformations. Large-scale deformations are handled with an Eulerian approach for finite element computations, which can operate directly on the image voxel mesh. Subsequently, dense correspondence between the modified atlas and patient image is established using nonrigid registration. The method offers opportunities in atlas-based segmentation of tumor-bearing brain images as well as for improved patient-specific simulation and prognosis of tumor progression.  相似文献   
73.
The present work examines the in vitro antioxidant properties of the essential oil and various extracts prepared from the herbal parts of Ferula orientalis A. (Apiaceae). The highest 2,2-diphenyl-l-picrylhydrazyl (DPPH) radical-scavenging activity was found in the polar extract, e.g. methanol–water (1:1), obtained from non-deodorised materials with IC50 values at 99.1 μg/ml. In the β-carotene/linoleic acid assay, the deodorised acetone extract exhibited stronger activity than the polar one. The relative antioxidant activities (RAA%) of the extracts ranged from 10.1% to 76.1%, respectively. Extraction with methanol–water (1:1) mixture was concluded to be the most appropriate method in terms of higher extract yield, as well as effectiveness, observed in both assays. Although the essential oil showed antioxidative potential, it was not as strong as that of positive control (BHT). GC/MS analysis of the essential oil resulted in the identification of 39 compounds, β-phellandrene (23.6%), (E)-β-ocimene (13.8%), α-pinene (12.5%), α-phellandrene (11.5%) and dehydro-sesquicineole (10.1%) being the major components.  相似文献   
74.
The effect of oregano on the oxidative stability of cottonseed oil during frying of potato chips and on the storage stability of the produced chips was studied. The ground spice or an ethanol‐derived extract thereof was added to the oil at a concentration of 2 g l?1 (dry basis) before frying. The results showed that both ground oregano and its ethanol‐derived extract decreased the rates of accumulation of conjugated dienes, polar compounds, polymerised triglycerides, dimeric triglycerides as well as p‐anisidine value (p‐AV) of the frying oil. The major decrease was observed in the accumulation of polymerised and dimeric triglycerides. The accumulation of oxidised triglycerides showed a low decrease with the addition of oregano, while the hydrolytic compounds formed during frying were not affected. No significant difference (at 95% significance level) between ground oregano and its ethanol‐derived extract was observed. The storage stability of potato chips removed from the fryer at various time intervals was estimated by the rates of increase in peroxide value and conjugated dienes of the oil absorbed in the chips. Both rates were depressed when oregano was added to the frying oil; the protective action of oregano extract was considerably greater (at 95% significance level) than that of ground oregano. Copyright © 2003 Society of Chemical Industry  相似文献   
75.
Intelligent Service Robotics - This paper proposes a hierarchical visual architecture for perceiving garments’ configuration independently from their type for the robotic unfolding task....  相似文献   
76.
Bismuth Oxychloride (BiOCl) is a p-type indirect bandgap semiconductor with gaps in the range of 3.2–3.5 eV. In this work, BiOCl was synthesized by a simple hydrothermal method along with variation in the concentration of the capping agent citric acid to perform the tuning of the morphology of the samples. The samples were analyzed by various techniques for insight into phase formation, morphology, chemical composition etc. The as-synthesized nanomaterials exhibited extensive variation in crystal structures due to variation in the citric acid ratio. Finally the as-synthesized samples were utilized for effective photocatalytic degradation of toxic textile dyes like Rhodamine B under visible light irradiation and also for hydrogen evolution by electrochemical method. The structural tuning resulted in a noticeable increment in hydrogen evolution observed in an acidic medium for a low overpotential. The as-synthesized material can thus be utilized for waste-water remediation and various electrochemical water-splitting related applications.  相似文献   
77.
Different applications require iron oxide nanoparticles (IONPs) of varying size, shape, crystallinity, and surfaces that can be controlled through the synthesis reaction conditions. Under ambient conditions, Magnetospirillum magneticum AMB-1 builds uniform Fe3O4 IONPs with shapes and crystal forms difficult to achieve with chemical synthesis. Genetic engineering can be used to change their properties, but there are few tools to fine-tune expression over a wide range. To this end, ribosome binding sites, minimal constitutive promoters, and inducible systems (IPTG, aTc, and OC6) with large dynamic range are designed. These are used to control M. magneticum genes that affect IONP properties, including size (mamC), morphology (mms6), chain length (mamK), and surface coating (mamC fusions). These systems increase the fraction of IONPs that are less than 30 nm, produce rounded particles, and lead to the production of intracellular chains with 24 or more IONPs. In addition, the R5 peptide from diatoms is found to silica coat the surface of metal oxide nanoparticles (Fe, Ti, Ta, Hf) and can be genetically directed to the IONP surface. This work demonstrates the genetic control of IONP properties, but also highlights the robustness of the system, which complicates genetic engineering to produce radically different particles and structures.  相似文献   
78.
79.
The effect of successively replacing (10%, 20%, and 30%) wheat flour with dietary fiber (DF) from wheat, oat, barley, and maize or cereal bran (CB) from wheat, oat, and rice on cake batter, final cake quality parameters, as well as on product shelf-life was studied. Batter viscosity (control, 2.96; wheat fiber 30%, 20.21; rice bran 10%, 0.47 Pa sn), cake-specific volume (control, 2.27; wheat fiber 20%, 2.83; rice bran 30%, 1.94 cm3/g), porosity (control, 0.75; wheat fiber 30%, 0.81; rice bran 30%, 0.69), and crumb moisture content (control, 20.07%,; wheat fiber 30%, 26.45%; oat bran 30%, 13.89%) increased significantly (P < 0.05) with DF addition but decreased with CB addition. Addition of DF resulted in softer crumb texture (Control, 4.20 N; wheat fiber 20%, 3.19 N), while CB addition increased crumb firmness (rice bran 30%, 10.84 N), respectively. Minor differences were observed in the crumb and crust color of the DF cakes with respect to the control. Addition of CB decreased the L values of crumb color significantly and the decrease increased with increased level of CB incorporation. DF addition led to cakes with greater acceptance by panelists than CB addition, similar to the control. DF cakes stored in polyethylene bags at 25 °C and 60% relative humidity for 6 days showed delayed moisture loss and lower firmness compared to CB cakes. The optimal level of incorporation based both on the objective and sensory characteristics results was found 20% for DF and 10% for CB, respectively. Concluding, by incorporating DF or CB properly, cakes with improved nutritional value can be manufactured.  相似文献   
80.
The adsorption of thiram and disulfiram onto alpha-Al2O3 and montmorillonite clay has been studied in the presence of small carboxylate anions, bicarbonate, formate, and oxalate. At natural concentrations, HCO3- enhances dramatically the adsorption of both pesticides on alpha-Al2O3 and clay. An analogous significant enhancement of pesticide adsorption is also observed in the presence of formate and oxalate. Density functional theory calculations demonstrate that in solution a stable molecular complex between one molecule of thiram and one molecule of HCO3- is formed with interaction energy -35.6 kcal/mol. In addition, two H20 molecules further stabilize it by an interaction energy of -3.6 kcal/mol. This clustering [thiram- HCO3- -2H2O] leads to a change of the electronic structure and the ultraviolet-visible spectrum of thiram that is observed experimentally. Surface complexation modeling shows that the molecular cluster [thiram-HCO3- -2H2O], which bears a total net charge of -1, is responsible for the observed enhanced adsorption on the charged surface of alumina and clay at pH below their points of zero surface charge. The results reveal a novel pervasive role of carboxylate anions and particularly HCO3- on the adsorption of dithiocarbamate pesticides in natural waters.  相似文献   
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