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61.
We present an interpolation algorithm for adaptive color image zooming. The algorithm produces the magnified image in one scan of the input image, and is fully automatic since does not involve any a priori fixed threshold. Given any integer zooming factor n, each pixel of the input image generates an n×n block of pixels in the zoomed image. For the currently visited pixel of the input image, the pixels of its associated block are first assigned tentative values, which are then adaptively updated before building the next block. The method is suggested for RGB images, but can equally be employed in other color spaces. Peak signal to noise ratio (PSNR) and Structural SIMilarity (SSIM) are used to evaluate the performance of the algorithm.  相似文献   
62.
Red wine is a widely consumed beverage with multiple beneficial effects on human health. In the present paper, the anticaries properties of red wine were studied in vitro and ex vivo. Our in vitro findings shows that dealcoholised red wine, besides exerting antibacterial activity, strongly interferes with Streptococcus mutans adhesion to saliva-coated hydroxyapatite (sHA) beads, promotes its detachment from sHA, and powerfully inhibits in vitro biofilm formation. The main components responsible for such activities were found to be proanthocyanidins. The ability of red wine to inhibit ex vivoS. mutans biofilm formation on the occlusal surface of natural human teeth also was demonstrated.  相似文献   
63.
A model calibration technique is considered for the estimation of material parameters in free-standing thin foils. The experimental apparatus is inspired by bursting strength testers for paper, textile fabrics and polymer coatings such as geo-membranes. The procedure referred to herein consists of the following phases. A controlled fluid pressure is applied to the foil specimen placed on an horizontal plane with a suitably shaped hole. The induced out-of-plane displacements are measured by a laser profilometer. The material parameters are then inferred from these measurements through inverse analysis, by simulation of the test and minimisation of a suitable norm which defines the discrepancy between measured and computed displacements. Potentialities and limitations of the proposed method are assessed on the basis of computer-generated “pseudo-experimental” data, where modelling errors are ruled out. The identifiability of some industrially meaningful material parameters is established.  相似文献   
64.
This paper describes the setup of the Book Structure Extraction competition run at ICDAR 2009. The goal of the competition was to evaluate and compare automatic techniques for deriving structure information from digitized books, which could then be used to aid navigation inside the books. More specifically, the task that participants faced was to construct hyperlinked tables of contents for a collection of 1,000 digitized books. This paper describes the setup of the competition and its challenges. It introduces and discusses the book collection used in the task, the collaborative construction of the ground truth, the evaluation measures, and the evaluation results. The paper also introduces a data set to be used freely for research evaluation purposes.  相似文献   
65.
Water-borne paint coatings while used outdoors, show good protective behaviour on metals, even though they can take up and release much moisture. As experience shows for physically drying paint coatings, the changing wet-and-dry environment improve their corrosion protection properties. To find out the reasons, eight model coatings – built up from various combinations of layers made of the physically drying styrene-acrylate, and the oxidatively drying alkyd-acrylate based paints – were tested on metal substrate by electrochemical impedance spectroscopy; water uptake/release kinetics was followed by gravimetry on self-standing films made of the above resins. The results of experiments simulating the weathering effects (wet–dry cycling and heating) with the physically drying paint coatings lead us to the conclusions that: (i) water uptake and release removes the water-soluble components from the film and thereby contributes to the good or improving corrosion protection feature, and explains the observation that these coatings perform satisfactorily outdoors and (ii) water release is always much faster than the uptake which helps to keep the interior of the coating dry protecting the metal surface against moisture.  相似文献   
66.
The evolution of heat damage during storage of tomato pulp, puree and paste was studied by accelerated aging tests. Heat damage indices—5‐hydroxymethyl‐2‐furfural (HMF), furosine and colour changes (ΔE)—were evaluated for tomato products stored at 30, 40 and 50 °C for up to 90 days. Furosine and ΔE values increased following pseudo‐zero‐order kinetics, and the higher the solid content of the products, the higher were the rate constant values. HMF formation followed pseudo‐first‐order kinetics in tomato pulp and pseudo‐zero‐order kinetics in puree and paste samples. Data show that heat damage reactions in tomato products proceed even at room temperature, and the kinetic model provided can be used to predict changes occurring during shelf‐life. © 2002 Society of Chemical Industry  相似文献   
67.
Project success is a widely studied and discussed phenomenon of project management. Whilst certain success criteria and success factors are common across different project types, there are unique criteria and factors that apply only to specific projects. This paper presents the development and investigation of the attributes of the success criteria and factors of organisational event projects, as well as an analysis of the relationship between the criteria and factor areas. The study is based on a questionnaire survey of world and European championships. The findings of the study are of interest because they distinguish the success factors that represent relationship orientation and task focus. An analysis of the correlations suggests that relationship-oriented success factors, such as communication, co-operation and project leadership, play a crucial role in carrying out successful organisational event projects.  相似文献   
68.
Renal function recovery (RFR), defined as the discontinuation of dialysis after 3 months of replacement therapy, is reported in about 1% of chronic dialysis patients. The role of personalized, intensive dialysis schedules and of resuming low‐protein diets has not been studied to date. This report describes three patients with RFR who were recently treated at a new dialysis unit set up to offer intensive hemodialysis. All three patients were females, aged 73, 75, and 78 years. Kidney disease included vascular‐cholesterol emboli, diabetic nephropathy and vascular and dysmetabolic disease. At time of RFR, the patients had been dialysis‐dependent from 3 months to 1 year. Dialysis was started with different schedules and was progressively discontinued with a “decremental” policy, progressively decreasing number and duration of the sessions. A moderately restricted low‐protein diet (proteins 0.6 g/kg/day) was started immediately after dialysis discontinuation. The most recent update showed that two patients are well off dialysis for 5 and 6 months; the diabetic patient died (sudden death) 3 months after dialysis discontinuation. Within the limits of small numbers, our case series may suggest a role for personalized dialysis treatments and for including low‐protein diets in the therapy, in enhancing long‐term RFR in elderly dialysis patients.  相似文献   
69.
Two unsupervised pattern recognition techniques such as stepwise linear discriminant analysis (SLDA) and Soft Independent Modeling of Class Analogy (SIMCA) were used to classify tomato samples in categories corresponding to the cultivation areas. The same approach was used for triple concentrated pastes for discrimination between two different Italian production areas. Accordingly, HS-SPME-GC-MS with 85 ??m carboxen/polydimethylsiloxane fiber was used for the determination of the volatile fraction in tomatoes and triple concentrate tomato pastes samples. Ethyl isobututanoate was used as internal standard for semiquantitative analysis and the concentration data (??g/kg) of 38 compounds for tomatoes and of 32 compounds for triple concentrates were used in following chemometric analysis. Sixteen and three variables were selected by forward stepwise LDA for tomatoes and pastes, respectively. SLDA and SIMCA models showed respectively 96% and 94% in term of prediction ability for tomatoes. The two supervised techniques provided 100% and 97% in prediction of the production areas of tomato pastes, respectively.  相似文献   
70.
The stria vascularis (SV) contributes to cochlear homeostasis and consists of three layers, one of which contains the blood-labyrinthic barrier (BLB), with a large number of bovine cochlear pericytes (BCPs). Cisplatin is a chemotherapeutic drug that can damage the SV and cause hearing loss. In this study, cell viability, proliferation rate, cytotoxicity and reactive oxygen species production were evaluated. The protein content of phospho-extracellular signal-regulated kinases (ERK) 1/2, total ERK 1/2, phospho-cytosolic phospholipase A2 (cPLA2), total cPLA2 and cyclooxygenase 2 (COX-2) and the release of prostaglandin E2 (PGE2) and vascular endothelial growth factor (VEGF) from BCPs were analyzed. Finally, the protective effect of platelet-derived growth factor (PDGF-BB) on BCPs treated with cisplatin was investigated. Cisplatin reduced viability and proliferation, activated ERK 1/2, cPLA2 and COX-2 expression and increased PGE2 and VEGF release; these effects were reversed by Dexamethasone. The presence of PDGF-BB during the treatment with cisplatin significantly increased the proliferation rate. No studies on cell regeneration in ear tissue evaluated the effect of the PDGF/Dex combination. The aim of this study was to investigate the effects of cisplatin on cochlear pericytes and propose new otoprotective agents aimed at preventing the reduction of their vitality and thus maintaining the BLB structure.  相似文献   
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