Demosaicing algorithms for area- and line-scan cameras in print inspection

Most color image sensors use color filter arrays (CFA). With this sensor design the captured information at each sensor pixel position is restricted to a specific spectral portion (typically red, green and blue bands). To obtain the missing color responses at each pixel position, so-called CFA demosaicing algorithms are commonly used. We propose two new CFA demosaicing algorithms, which are well suited for industrial print inspection with respect to the requirements in accuracy and speed. As a main contribution, we introduce novel demosaicing algorithms for specific high-speed color digital time delay and integration (DTDI) CFA line-scan cameras. We compare the suggested CFA demosaicing algorithms to state-of-the art algorithms for area and line-scan camera operation modes. We show that the two new algorithms perform superior to conventional algorithms as indicated by reconstruction error.     

Curie temperature enhancement in partially disordered Sr2FeReO6 double perovskites

Two samples of the double perovskite Sr₂FeReO₆ have been synthesized by (1) soft-chemistry procedures and (2) high-pressure methods. The sample prepared by a soft-chemistry technique presents 75% of Fe/Re cationic order whereas the one prepared by the application of high external pressure generates a complete Fe/Re cationic order. Both materials have been characterized by X-ray diffraction, neutron powder diffraction and magnetic measurements. The magnetic properties of both oxides have been compared, observing that the specimen prepared via soft-chemistry procedures presents an enhanced Curie temperature of 445 K, although the sample prepared under high-pressure techniques displays a superior saturation magnetization. This behavior is explained as a consequence of the presence, in the partially disordered sample, of Fe-rich islands containing strong Fe-O-Fe antiferromagnetic couplings, able to nucleate and lock the ferromagnetic interactions of the ordered regions, thus increasing the global Curie temperature of the partially disordered material.     

Influence of processing on the levels of amines and proline and on the physico-chemical characteristics of concentrated orange juice

The influence of processing on the levels of bioactive amines and proline as well as on some physico-chemical characteristics of concentrated orange juice was investigated. Samples were collected at seven points of a production line on three non-consecutive days, and analysed for the levels of 12 bioactive amines, proline, and reducing and non-reducing sugars, and for some physico-chemical characteristics. Among the amines analysed, only putrescine, spermidine and synephrine were found in the samples at all processing stages. Significant differences were observed for spermidine and total amine levels throughout processing. Synephrine and putrescine were resistant to processing. Proline levels changed significantly throughout processing, as did levels of reducing and non-reducing sugars. The pH varied from 3.59 to 3.72, acidity from 0.873 to 0.918 g citric acid/100 mL, and density from 1.0378 to 1.0970 g/mL. Among these parameters, pH, acidity and density were significantly affected by processing.     

Neutral glycosphingolipid content of ovine milk

Milk glycosphingolipids (GSL) have been reported to participate in the newborn's defense against pathogens. Taking this into account, in this study we determined the neutral GSL content of ovine milk, including its fatty acid profile. Its role in bacterial adhesion was also addressed by immunodetection of separate GSL in a high-performance thin-layer chromatography overlay assay. Ovine milk has a neutral GSL pattern similar to human milk and includes lactosylceramide (LacCer; 45.7%), monohexosylceramide (glucosylceramide and galactosylceramide, 31.2%), globotriaosylceramide (Gb3; 19.1%), and globotetraosylceramide (Gb4; 3.5%). Globotriaosylceramide and Gb4 are present in human but not bovine milk. Neutral GSL contained C23:0 and C24:0 as the most abundant fatty acids, a finding consistent with its high content of very long chain fatty acids (longer than C20). Most fatty acids were saturated and had a low content of polyunsaturated fatty acids. Bovine enterotoxigenic Escherichia coli strains bound strongly to LacCer and showed a weak binding to monohexosylceramide. The K99 strain also bound strongly to Gb3, and F41 to Gb4. Lactosylceramide, monohexosylceramide, and Gb3 were also observed to bind to human uropathogenic E. coli strains. The results reported here show the ability of neutral GSL in ovine milk to bind to E. coli strains. These compounds could be used as an alternative and available source to supplement infant or bovine formulas with a view to preventing bacterial infections.     

Simulations of biomolecules: Characterization of the early steps in the pH-induced conformational conversion of the hamster,bovine and human forms of the prion protein

As computer power increases, so too does the range of interesting biomolecular phenomena and properties that can be simulated. It is now possible to simulate complicated protein conformational changes at ambient or physiological temperatures. In this regard, we are attempting to map the conformational transitions of the normal, cellular prion protein (PrP(C)) to its infectious scrapie isoform (PrP(Sc)), which causes neurodegenerative diseases in many mammals. These two forms have identical sequences and are conformational isomers, with heightened formation of beta-sheet structure in the scrapie form. Conversion can be triggered by lowering the pH, but thus far it has been impossible to characterize the conformational change at high resolution using experimental methods. Therefore, to investigate the effect of acidic pH on PrP conformation, we have performed molecular-dynamics simulations of hamster, human and bovine forms of the prion protein in water at neutral and low pH. In all cases the core of the protein is well maintained at neutral pH. At low pH, however, the protein is more dynamic, and the sheet-like structure increases both by lengthening of the native beta-sheet and by addition of a portion of the N-terminus to widen the sheet by another 2-3 strands.     

Evaluation of high-frequency sinusoidal waveform superposed with third harmonic for stable operation of metal halide lamps

In this paper, a novel topology to supply metal halide (MH) lamps using sinusoidal waveform with superposed third harmonic is proposed. By employing this technique, the lamp is supplied with an approximated square waveform, but it reduces the harmonic content and, therefore, electromagnetic interference and radio-frequency interference. The proposed topology is analyzed and designed for a 35-W MH lamp with ceramic discharge tube. Experimental results prove that lamp operation is stable at operating frequencies where acoustic resonances were previously observed when supplied with purely sinusoidal waveforms. In conclusion, the proposed technique could be a feasible solution for stable operation of MH lamps.     

Physiopathology of vertebrobasilar ischemia

Although most of the studies concerning physiopathology of ischemia refer to cerebral hemispheres, it seems reasonable to consider that cellular and biochemical changes due to ischemia are similar in cerebellum and brain stem, which receive blood flow from vertebral and basilar arteries. Anyway, it must be noted that arterial distribution and anatomical structure of this part of the brain are quite distinct, so there might be differences in tissue vulnerability according to severity and duration of ischemia. Cellular injury from ischemia results, at first, as a consequence of energy failure that leads to loss of ionic homeosthasis and membrane potential. This runs a cascade of reactions which is responsible of injury progression. Reperfusion may potentiate this reactions if it does not occur early enough. Main mediators of these reactions are acidosis, citoplasmic calcium overload and excess of free radicals. Development of an inflammatory response and injury to microcirculation contribute to perpetuate the process.     

Experimental animal models in cerebral ischemia

This paper describes the potential markers of cell death and connective tissue degradation which might serve as markers of periodontal disease activity. The first section deals with enzymes released by dead and degenerating cells. Firstly, it describes how these pass from the periodontal tissues into gingival crevicular fluid (GCF) and explains that these enzymes have been used as markers of cell death in medicine for several decades. It then discusses the main enzymes in this group, aspartate amino transferase (AST) and lactate dehydrogenase (LDH) and reviews those studies which have attempted to relate these enzymes to periodontal disease severity and activity. Secondly, it describes the potential markers of connective tissue degradation, fibronectin, hydroxyproline-containing peptides and glycosaminoglycans (GAGs) and explains how these are produced. Finally, it describes the only commercial test kit for markers in this group (GCF-AST).