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A multi-purpose digital image watermarking using fractal block coding   总被引:1,自引:0,他引:1  
In this paper, a new multi-purpose watermarking technique is presented which satisfies both verification and authentication purposes simultaneously by embedding a binary watermark into the image. The proposed method uses a special type of fractal block coding with a local search region with contrast scaling and mean of range block as its parameters. It also utilizes Fuzzy C-Mean clustering to specify the watermark bits. To overcome the high computational complexity of fractal coding, a new simple coding method is also presented which improves the robustness of the watermarking and decreases the run time of fractal block coding in the watermarking procedure. To measure the fragility and robustness of the method to signal distortions such as JPEG compression, median filter, and additive noise, some experiments were employed. The experimental results showed that the proposed method has provided a sensitive authentication and a reliable verification.  相似文献   
74.
In this work, Cu–P–SiC composite coatings were deposited via electroless plating with the addition of sodium hypophoshite (NaH2PO2) as a reducing agent. The coating compositions deposited were determined by using energy dispersive X-ray spectroscopy (EDX). The surface morphology of the coatings that were analyzed using scanning electron microscopy (SEM) showed that SiC particles were uniformly distributed by virtue of surfactant addition and mechanical stirring. The anti-corrosion properties of Cu–P and Cu–P–SiC coatings in NaCl and HCl solutions were investigated by the weight loss and potentiodynamic polarization techniques. The results showed that the corrosion resistance of Cu–P–SiC coatings was superior to that of electroless Cu–P coatings and carbon steel substrates in various concentrations of NaCl and HCl solutions.  相似文献   
75.
Peanut Allergy: Characteristics and Approaches for Mitigation   总被引:1,自引:0,他引:1  
Peanut allergy has garnered significant attention because of the high sensitization rate, increase in allergy, and severity of the reaction. Sufficiently reliable therapies and efficient mitigating techniques to combat peanut allergy are still lacking. Current management relies on avoiding peanuts and nuts and seeds with homologous proteins, although adverse events mostly occur with accidental ingestion. There is a need for hypoallergenic peanut products to protect sensitized individuals and perhaps serve as immunotherapeutic products. Alongside traditional practices of thermal and chemical treatment, novel processing approaches such as high‐pressure processing, pulsed ultraviolet light, high‐intensity ultrasound, irradiation, and pulsed electric field have been performed toward reducing the immunoreactivity of peanut. Covalent and noncovalent chemical modifications to proteins also have the tendency to alter peanut allergenicity. Enzymatic hydrolysis seems to be the most advantageous technique in diminishing the allergenic potential of peanut. Furthermore, the combined processing approach (hurdle technologies) such as enzymatic hydrolysis followed by, or in conjunction with, roasting, high pressure and heat, ultrasound with enzymatic treatment, or germination have shown a significant reduction of peanut immunoreactivity and may emerge as useful techniques in reducing the allergenicity of peanut and other foods. This study represents our current knowledge about the alterations in allergenic properties of peanut via different processing mechanisms as well as evaluating its future potential, geographical based data on increasing sensitization, clinical relevance, eliciting dose, and current management of peanut allergy. Furthermore, the molecular characteristics and clinical relevance of peanut allergens have been discussed.  相似文献   
76.
The synthesis of Cu(OH)2 nanoparticles in a solution phase has been realised with high yield at low cost by simply dropping ammonia solution into an aqueous solution of CuCl2 at ambient temperature. Furthermore, well-defined CuO nanostructures were produced by thermal dehydration of the as-prepared Cu(OH)2 nanostructures in the solid state. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared (FT-IR) were used to characterise the products. The electrochemical behaviour of three ß-blocker drugs on copper-oxide nanoparticle modified carbon paste electrodes was investigated. The modified electrodes showed excellent catalytic activity towards the oxidation of atenolol, carvedilol and propranolol in buffer solution. The linear concentration range of the proposed sensor for the atenolol, carvedilol and propranolol detection were 12–96, 5–37 and 10–104?µM, respectively.  相似文献   
77.
Synthetic phenolic food additives occupy an important place in food industry. Among the various food additives butylated hydroxyanisol (BHA), tertiary butylhydroquinone (TBHQ), 2-tert-butyl-4-methylphenol (TBMP) and propyl gallate (PG) have potential to form molecular complexes with nucleic acid structure and have attracted recent attention for their prospective industrial utility. This review highlights the properties of these synthetic phenolic food additives and their interactions with calf thymus DNA (CT-DNA) reported by several research groups. Various analytical techniques were employed including absorbance and fluorescence spectroscopies, viscosity, voltammetry and thermodynamic studies to provide more details about binding mechanism of these food additives with DNA.  相似文献   
78.
Minke whale (Balaenoptera acutorostrata) blubber is rich in organohalogen contaminants, mercury, and n-3 fatty acids. In the present study we show that a daily intake of 50-200 g of minke whale blubber causes an impairment of the nonspecific and specific cellular immune system in the West Greenland sledge dog (Canis familiaris). Immune reactions were measured by mitogen (PHA, Con A) and antigen (KLH) intradermal testing, and as the study used exposure levels similar to those of Inuits and polar bears (Ursus maritimus), it is reasonable to infer that Inuits and polar bears suffer from similar decreased resistance to diseases. It is speculated that food sources are depleted by thinning sea ice due to climate change and that more research should assess the forecasted rise in additive immunopathy effects in polar bears. Additionally, our study suggests that the fatty acid composition may be of importance when investigating combined immunotoxic effects of contaminated food resources in future Inuit and polar bear studies.  相似文献   
79.
Hydroxy apatite (HA) is effectively used as a bioimplant material because it closely resembles bone apatite and exhibits good biocompatibility. So, in this research, HA powders were produced by calcinations of natural bones including human, bovine, camel and horse bones, and also via sol-gel method. Powders characterizations of natural HA and Synthetic HA were studied by X-ray powder diffraction (XRD), X-ray fluorescence (XRF), Fourier transform infrared (FTIR) and scanning electron microscopy (SEM), combined with transmission electron microscopy (ТЕМ). In order to verify the biocompatibility of these HA powders, MTT assay was applied. The XRD results showed that the HA powders were successfully produced by using different sources. Also, it was obvious from XRF analysis that the main components of them were Ca and P. Furthermore, it was seen that the size of particles was in the nanometric scale and they showed agglomerates consisting of numerous nanocrystals. FTIR spectra of all samples proved the presence of various CO 3 2- , PO 4 3- and OH groups in the powders. In addition, the MTT assay revealed that the cells proliferations in the presence of horse and human HA nanopowders were stimulated.  相似文献   
80.
Europe has experienced fast-paced urbanization development over the past three decades. This paper empirically investigates the long-run equilibrium relationships and causal relationships among urbanization, renewable energy consumption, and CO2 emissions, and this is important for EU countries’ future sustainable development. DOLS and FMOLS approaches are used for the period 1992–2014 .

Granger causality results show that there is a unidirectional relationship from CO2 emissions to urbanization, and there is no causality between renewable energy consumption and CO2 emissions. The results have important implications for EU policymakers on the path toward a sustainable society. Urbanization can have negative impacts on the natural environment with the net effect being hard in EU countries.  相似文献   

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