A visible-light and infrared video database for performance evaluation of video/image fusion methods

Multidimensional Systems and Signal Processing - In general, the fusion of visible-light and infrared images produces a composite representation where both data are pictured in a single image. The...     

Generalized Hermitian Radial Basis Functions Implicits from polygonal mesh constraints

In this work we investigate a generalized interpolation approach using radial basis functions to reconstruct implicit surfaces from polygonal meshes. With this method, the user can define with great flexibility three sets of constraint interpolants: points, normals, and tangents; allowing to balance computational complexity, precision, and feature modeling. Furthermore, this flexibility makes possible to avoid untrustworthy information, such as normals estimated on triangles with bad aspect ratio. We present results of the method for applications related to the problem of modeling 2D curves from polygons and 3D surfaces from polygonal meshes. We also apply the method to problems involving subdivision surfaces and front-tracking of moving boundaries. Finally, as our technique generalizes the recently proposed HRBF Implicits technique, comparisons with this approach are also conducted.     

Ferritic stainless steel welding with the A-TIG process

The main advantage of the TIG with flux process (A-TIG welding) is the possibility of obtaining greater penetration of the weld bead while employing the same welding parameters as conventional TIG welding. Various studies have shown the influence of active fluxes on the geometric characteristics of stainless steel austenitic welds. However, little is known about the influence of this process on the geometric and metallurgical characteristics of the weld beads in ferritic stainless steels. In this work, different types of flux are applied when welding ferritic stainless steel with the objective of verifying possible influences on the weld bead's profile, on its visual appearance, on the microstructure, on the hardness of the welded zone and on the impact resistance (Charpy test). The bead-on-plate welds were produced without using any addition metal. Six types of flux were used – one being an oxide produced in a laboratory (TiO₂) and five commercial fluxes. The results showed that use of the flux allows an increase in penetration with significant changes in the appearance of the weld bead. It was also confirmed that the microstructure and the hardness of the weld bead for the steel studied were not affected by the type of flux used, with the microstructure analysed under an optical microscope. The steel in the study showed a high degree of fragility at ambient temperature.     

Phytochemical Polyphenol Extraction and Elemental Composition of Vitis labrusca L. Grape Juices Through Optimization of Pectinolytic Activity

Grape juice is a natural source of polyphenols with potential health benefits. The aim of this study was to assess the optimized basis of the pectinolytic activity through a multivariate design for the bioactive enrichment of polyphenols in grape juices and to evaluate the effect of pectinases on the extraction of minerals by ICP-MS and FAAS. Grape juices were treated with pectinases Everzym® Color and Rapidase® Smart at different conditions of enzyme concentration (0.16–1.84 g L^?1), temperature (14.8–83.6?ºC), and incubation time (9.6–110.5 min), and the effect on total phenolics, anthocyanin content, and antioxidant activity of juices were determined by employing a second-order central composite design in combination with response surface methodology. The different conditions showed significant variations in polyphenol levels of grape juices. For both of the enzymes, the increase of temperature and enzyme concentration led to a higher extraction of polyphenols, with a significant effect. Estimated effects depict a good correlation among dependent variables. For Rapidase, the optimized extraction of polyphenols was determined at an enzyme concentration of 1.57 g L^?1 and at a temperature of 54.8?ºC. For Everzym, higher concentrations of polyphenols were obtained at the enzyme concentration of 1.30 g L^?1 at 46.8?ºC. The extraction using the Rapidase enzyme significantly increased the levels of Na, K, Mg, and Fe in grape juices (p?<?0.05). The pectinolytic activity increased the polyphenol and mineral concentrations in grape juices. In addition, the optimal conditions of the pectinolytic treatment comprise a feasible alternative to improve the bioactive potential of grape juices.     

KINETICS OF WATER VAPOR SORPTION BY FREEZE DRIED PAPAYA

The hygroscopic potential of freeze dried papaya in the form of powder and granules was studied for several temperatures (23,33 and 43PC) and relative humidities (49 to 90%). For such conditions the kinetics of water sorption was established. The results show the influence of the amount of water absorbed, the environmental relative humidity and temperature on water sorption rates for this type of product. An intriguing behavior was found far the rates of water sorption as influenced by the absolute temperature, and at the critical level of 60% relative humidity, this influence is very much reduced.     

Direct Determination of Trace Elements in Meat Samples via High-Resolution Graphite Furnace Atomic Absorption Spectrometry

This work presents a direct and straightforward approach for the determination of trace elements in fish muscle, oyster, and bovine liver via direct solid sample analysis (SS) using high-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GF AAS). The preliminary studies revealed the presence of spectral interferences at the analytical line of Ni at 231.096 nm, which could be corrected subtracting the spectrum of SiO and PO from the sample spectra using least-squares background correction. Moreover, all meat samples were proven homogeneous according to the homogeneity factor (H _e) (all values were <10 mg^½). Pyrolysis (Tp) and atomization (Ta) temperatures were studied and optimized as 800 °C (Tp) and 2500 °C (Ta) for Mn, 700 °C (Tp) and 2600 °C (Ta) for Ni, and 600 °C (Tp) and 2500 °C (Ta) for Rb. Calibration against aqueous standards was proven feasible for Mn determination, whereas Ni and Rb required calibration against solid standards for their quantification. The detection limits achieved were demonstrated adequate for application to food analysis (0.005 μg g^?1 for Mn, 0.002 μg g^?1 for Ni, and 0.1 μg g^?1 for Rb). The developed method was successfully applied for the elemental analysis of fish muscle, oyster, and bovine liver and three certified reference materials, demonstrating good agreement with the certified values and with the reference technique at a 95 % statistical confidence level.     

Synthesis,DNA Binding,and Antiproliferative Activity of Novel Acridine-Thiosemicarbazone Derivatives

In this work, the acridine nucleus was used as a lead-compound for structural modification by adding different substituted thiosemicarbazide moieties. Eight new (Z)-2-(acridin-9-ylmethylene)-N-phenylhydrazinecarbothioamide derivatives (3a–h) were synthesized, their antiproliferative activities were evaluated, and DNA binding properties were performed with calf thymus DNA (ctDNA) by electronic absorption and fluorescence spectroscopies. Both hyperchromic and hypochromic effects, as well as red or blue shifts were demonstrated by addition of ctDNA to the derivatives. The calculated binding constants ranged from 1.74 × 10⁴ to 1.0 × 10⁶ M⁻¹ and quenching constants from −0.2 × 10⁴ to 2.18 × 10⁴ M⁻¹ indicating high affinity to ctDNA base pairs. The most efficient compound in binding to ctDNA in vitro was (Z)-2-(acridin-9-ylmethylene)-N-(4-chlorophenyl) hydrazinecarbothioamide (3f), while the most active compound in antiproliferative assay was (Z)-2-(acridin-9-ylmethylene)-N-phenylhydrazinecarbothioamide (3a). There was no correlation between DNA-binding and in vitro antiproliferative activity, but the results suggest that DNA binding can be involved in the biological activity mechanism. This study may guide the choice of the size and shape of the intercalating part of the ligand and the strategic selection of substituents that increase DNA-binding or antiproliferative properties.     

Hermite Radial Basis Functions Implicits

The Hermite radial basis functions (HRBF) implicits reconstruct an implicit function which interpolates or approximates scattered multivariate Hermite data (i.e. unstructured points and their corresponding normals). Experiments suggest that HRBF implicits allow the reconstruction of surfaces rich in details and behave better than previous related methods under coarse and/or non‐uniform samplings, even in the presence of close sheets. HRBF implicits theory unifies a recently introduced class of surface reconstruction methods based on radial basis functions (RBF), which incorporate normals directly in their problem formulation. Such class has the advantage of not depending on manufactured offset‐points to ensure existence of a non‐trivial implicit surface RBF interpolant. In fact, we show that HRBF implicits constitute a particular case of Hermite–Birkhoff interpolation with radial basis functions, whose main results we present here. This framework not only allows us to show connections between the present method and others but also enable us to enhance the flexibility of our method by ensuring well‐posedness of an interesting combined interpolation/regularization approach.     

Poly(vinyl chloride)‐b‐poly(hydroxypropyl acrylate)‐b‐Poly(vinyl chloride): Understanding the synthesis of an amphiphilic PVC block copolymer on a pilot scale

The aim of this work was to develop an understanding of the major difficulties associated with the scale‐up of the technology for the synthesis of poly(vinyl chloride) (PVC) block copolymers that contain hydrophilic segments, thus providing important directions to be followed in order to produce such new materials on the industrial scale. The synthesis was carried out in a two‐step process. First, the macroinitiator α,ω‐di(iodo)poly(hydroxypropyl acrylate) was synthesized in an aqueous medium by (single electron transfer)/(degenerative chain transfer) living radical polymerization (SET‐DTRP) catalyzed by Na₂S₂O₄. The block copolymer was then prepared by SET‐DTRP of vinyl chloride (VC) from the iodine‐terminal active chain ends of the macroinitiator, thereby leading to the formation of the block copolymer poly(vinyl chloride)‐b‐poly(hydroxypropyl acrylate)‐b‐poly(vinyl chloride). This report covers important aspects related to the characterization of the block copolymer produced and to the identification of the major limitations that must be overcome in order to produce this new material on the industrial scale. The results clearly show the differences between the theoretical predictions and the block copolymer compositions obtained by using a suspension polymerization method, which is the most‐used polymerization process in the PVC industry. J. VINYL ADDIT. TECHNOL., 19:94–104, 2013. © 2013 Society of Plastics Engineers     

Evaluation of the antioxidant,antiproliferative and antimutagenic potential of araçá-boi fruit (Eugenia stipitata Mc Vaugh — Myrtaceae) of the Brazilian Amazon Forest

Eugenia stipitata is a fruit from Amazonia rich in terpene, volatile compounds, fiber, and vitamin C. The fruit is recognized for its high antioxidant activity and has attracted much attention due to their potential health benefits to humans. The total polyphenols, antioxidant, antiproliferative, antimutagenic and antigenotoxic activities of E. stipitata ethanolic extract were investigated. Total polyphenols were determined by the Folin–Ciocalteu method and showed 184.05 ± 8.25 mg GAE/100 g. The radical scavenging activity was DPPH _IC50 0.69 ± 0.23 μg/mL and TAC-ORAC_FL 371.98 μmol.TE/100 g. The extract was evaluated for its ability to inhibit the growth of tumor cell lines and had not complete cystostatic effect against any of the tested cell lines. Antimutagenic and antigenotoxic activities were investigated by micronucleus test and comet assay in mice, respectively. Ethanolic extract of E. stipitata showed higher antimutagenic and antigenotoxic properties at the highest concentration tested (300 mg/kg of body weight). In conclusion, these results suggest that this fruit could be used as a preventive agent against cancer.