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51.
Internet is offering a variety of services that are assembled to accomplish requests made by clients. While serving a request, security of the communications and of the data exchanged among services is crucial. Since communications occur along specific channels, it is equally important to guarantee that the interactions between a client and a server never get blocked because either cannot access a selected channel. We address here both these problems, from a formal point of view. A static analysis is presented, guaranteeing that a composition of a client and of possibly nested services respects both security policies for access control, and compliance between clients and servers. 相似文献
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Maurizio Ferrari Giancarlo C. Righini 《International Journal of Applied Glass Science》2015,6(3):240-248
Glass-ceramics (GCs) are multiphase micro- or nano-crystalline materials produced by the controlled nucleation and crystallization of an amorphous glass through a proper heating or chemical process. Most optical applications require transparency, and this usually implies that the crystalline phase be made of nanocrystals. Transparent GCs are able to combine the advantages of all their components, glasses, and crystals. Incorporation of semiconducting, ferroelectrical, and nonlinear optical phases in glass matrices can produce very promising materials for different applications. A very important role is played by nanocrystals which are activated by luminescent species, as rare earth ions. The presence of the crystalline environment around a rare earth ion allows high absorption and emission across sections, and reduction in the nonradiative relaxations thanks to the lower phonon cut-off energy. Such materials may lead to real advances in optical amplifiers, up-conversion fibers, solid-state lasers, medical sensors, and several other devices, especially if combined with a guided-wave configuration, which allows high energy densities and efficient delivery of the transmitted optical beams. The present review article covers the properties and current state of transparent glass-ceramics for guided-wave devices, including the discussion of the preparation methods and of their spectral and luminescent properties. 相似文献
54.
Giulio Destri Paolo Marenzoni 《International Journal of Circuit Theory and Applications》1996,24(3):397-407
In this paper is presented the use of the discrete-time cellular neural network (DTCNN) paradigm to develop algorithms devised for general-purpose massively parallel processing (MPP) systems. This paradigm is defined in discrete N-dimensional spaces (lattices) and is characterized by the locality of the direct information transmission between the space points (cells) and by continuous values of data and parameters; the DTCNN paradigm is thus able to express most of the typical MPP applications. A general version of a DTCNN has been implemented and optimized for three MPP architectures, namely the Connection Machines CM-2 and CM-5 and the Cray T3D. The comparison between the three machine performances with those achieved by a standard SPARC-20 workstation shows that, particularly with large lattices, the speed-up allowed in the computational times is significant and the range of solvable problem sizes is widely extended. 相似文献
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Filippo Crimì Emilio Quaia Giulio Cabrelle Chiara Zanon Alessia Pepe Daniela Regazzo Irene Tizianel Carla Scaroni Filippo Ceccato 《International journal of molecular sciences》2022,23(2)
Adrenal incidentalomas (AIs) are incidentally discovered adrenal neoplasms. Overt endocrine secretion (glucocorticoids, mineralocorticoids, and catecholamines) and malignancy (primary or metastatic disease) are assessed at baseline evaluation. Size, lipid content, and washout characterise benign AIs (respectively, <4 cm, <10 Hounsfield unit, and rapid release); nonetheless, 30% of adrenal lesions are not correctly indicated. Recently, image-based texture analysis from computed tomography (CT) may be useful to assess the behaviour of indeterminate adrenal lesions. We performed a systematic review to provide the state-of-the-art of texture analysis in patients with AI. We considered 9 papers (from 70 selected), with a median of 125 patients (range 20–356). Histological confirmation was the most used criteria to differentiate benign from the malignant adrenal mass. Unenhanced or contrast-enhanced data were available in all papers; TexRAD and PyRadiomics were the most used software. Four papers analysed the whole volume, and five considered a region of interest. Different texture features were reported, considering first- and second-order statistics. The pooled median area under the ROC curve in all studies was 0.85, depicting a high diagnostic accuracy, up to 93% in differentiating adrenal adenoma from adrenocortical carcinomas. Despite heterogeneous methodology, texture analysis is a promising diagnostic tool in the first assessment of patients with adrenal lesions. 相似文献
57.
Mariarenata Sessa Alessandro A. Casazza Patrizia Perego Rong Tsao Giovanna Ferrari Francesco Donsì 《Food and Bioprocess Technology》2013,6(10):2609-2620
Phenolic compounds were extracted from grape marc by means of high pressure and temperature extraction. In order to increase their dispersability in the aqueous phase, the polyphenolic extracts were encapsulated at a final concentration of 0.1 % (w/w) in nanoemulsion-based delivery systems, which were formulated with natural ingredients, using either a liquid (sunflower oil) or a solid (palm oil) lipid phase, as well as the combination of a hydrophilic and hydrophobic emulsifier, and were produced by high-pressure homogenization. The delivery systems were characterized in terms of physicochemical stability under accelerated ageing (storage at 4 °C, 30 °C, and 55 °C for 14 days), by recording the evolution of the mean droplet size, the creaming index as well as the UV–vis absorption spectra of the encapsulated polyphenols. The antioxidant activity of the encapsulated extracts was measured with two different chemical assays (FRAP and ORAC) and a cellular antioxidant assay. Sunflower oil-based nanoemulsions resulted to be the most physically and chemically stable, with no significant variation of the mean droplet size and no degradation of the encapsulated compounds under the different conditions tested. The FRAP and ORAC assays showed that the antioxidant compounds, when encapsulated, are as available as unencapsulated polyphenols in scavenging the peroxyl radicals (ORAC), but are less available in reducing the ferric tripyridyltriazine complexes (FRAP). Remarkably, the cellular antioxidant activity was significantly higher for the encapsulated grape marc polyphenols than for the unencapsulated ones, suggesting the fundamental role of the nanoemulsions in favoring the delivery through the biological membranes. 相似文献
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59.
Cristhiane Caroline Ferrari Silvia Pimentel Marconi Germer José Maurício de Aguirre 《Drying Technology》2013,31(2):154-163
The purpose of this work was to study the effects of spray-drying conditions on the physicochemical characteristics of blackberry powder using a central composite rotatable design. Inlet air temperature (140–180°C) and maltodextrin concentration (5–25%) were employed as independent variables. Moisture content, hygroscopicity, anthocyanin retention, color, powder morphology, and particle size were analyzed. A higher inlet air temperature significantly increased the hygroscopicity of the powder, decreased its moisture content, and led to the formation of larger particles with smooth surfaces. Powders produced with higher maltodextrin concentrations were less hygroscopic, slightly lighter and less red, and had a lower moisture content. Anthocyanin retention was mainly affected by drying temperature due to the heat sensitivity of the pigment. The optimal processing conditions were an inlet air temperature of 140–150°C and maltodextrin concentration of 5–7%. Overall, these results indicate that good quality powders can be obtained by spray drying, with potential applications for the food industry. 相似文献
60.
Ana Paula Macedo ;Debora Taffarel Ferrari ;Roberta C Shimano ;Joao Paulo Mardegan Issa ;Alceu Afonso Jordao ;Antonio Carlos Shimano 《机械工程与自动化:英文版》2014,(6):542-546
The aim of this study is to evaluate the ability of physical training in the maintenance of muscle strength in rats with HFD (high-fat diet) after OVX (ovariectomy). Eighty Wistar rats are at eight weeks of age and weight 200 g which divided into 8 groups (n = 10) and treated for 12 weeks: GA: OVX + ND (normal diet), GB: OVX + ND + training, GC: sham + ND, GD: sham + ND + training, GE: OVX + HFD, GF: OVX + HFD + training, GG: sham + HFD and GH: sham + HFD + training. HFD consists of standard ration for rats with addition of 30% lipids. In training groups, physical training five training/week was conducted on a treadmill with adaptation period of three weeks up to 18 m/s for one hour, training were performed for 12 weeks. The sedentary animals remained in individual box. To analyze the effects of training and diet, tensile strength tests of the gastrocnemius muscles were conducted: the speed of 0.1 mm/min. Analysis of variance was performed to compare groups. The mean (SD) obtained for the maximum load (N) were: GA 57.77 (6.89), GB 62.74 (5.07), GC 49.45 (6.06), GD 59.42 (5.26) and GE 55.58 (4.72), GF 62.50 (4.56), GG 58.35 (4.54) and GH 56.67 (5.87), respectively. There were no differences for maximum load between surgeries (p = 0.004) and between treatments (p = 0.000). Differences were found also for the relationship surgery diet treatment (p = 0.007). For the variable stiffness (N/mm), there were not statistically significant differences: GA 5.03 (0.72), GB 5.08 (1.09), GC 5.17 (0.53), GD 5.35 (0.80), GE 5.52 (1.20), GF 5.36 (1.07), GG 4.83 (1.03) and GH 5.40 (0.73). For the toughness (N/mm), there were differences between treatments (p = 0.010) and the ratio diet treatment (p = 0.024): GA 455.00 (107.21), GB 541.96 (126.80), GC 394.97 (84.67), GD 566.90 (157.07); GE 424.63 (113.03), GF 478.07 (106.03); GG 517.44 (98.65? 相似文献