Log-based mining techniques applied to Web service composition reengineering

Web service compositions are becoming more and more complex, involving numerous interacting ad-hoc services. These services are often implemented as business processes themselves. By analysing such complex web service compositions one is able to better understand, control and eventually re-design them. Our contribution to this problem is a mining algorithm, based on a statistical technique to discover composite web service patterns from execution logs. Our approach is characterised by a “local” pattern’s discovery that covers partial results through a dynamic programming algorithm. Those locally discovered patterns are then composed iteratively until the composite Web service is discovered. The analysis of the disparities between the discovered model and the initial ad-hoc composite model (delta-analysis) enables initial design gaps to be detected and thus to re-engineer the initial Web service composition.     

Structural characterisation and antibacterial activity of PP/TiO2 nanocomposites prepared by an in situ sol–gel method

Polypropylene/titanium dioxide (PP/TiO₂) nanocomposites can be prepared using a novel method based on the hydrolysis–condensation reactions (sol–gel method) of titanium alkoxide inorganic precursors that have been premixed with polypropylene under molten conditions. The resultant nanocomposites were characterised by transmission electronic microscopy (TEM), X-ray diffraction, Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). These techniques showed the formation of the titanium oxi-hydroxide chemical structure (Ti_xO_y(OH)_z) with a diameter of approximately 10 nm in the polymer matrix. Furthermore, a condensation degree of around 17% was determined using XPS analysis. The antibacterial activity was tested according to the JIS Z 2801:2000 standard with Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) in the absence of light. Correlations between the microstructure and the chemical composition of PP/TiO₂ nanocomposites and the antibacterial properties of these nanocomposites were discussed. The structure of titanium oxi-hydroxide derivative particles (Ti_xO_y(OH)_z) within the polypropylene matrix has been shown to impact strongly on the antibacterial properties in comparison with the results obtained with a dispersion of anatase titanium dioxide into the PP.     

An integrated model for optimisation of production and quality costs

Whether an industrial organisation is involved with production of new goods or engaged in reverse logistics to recycle used products, the items produced that do not meet specifications can cost the organisation in many different ways. The administrative expenses of handling returned items and the cost of reworking the items that have failed in plant quality control or returned by customers can be of concern to the manufacturers. While these are measurable costs, there are other costs such as loss of customers’ good will which are hard, if not impossible, to estimate. The model presented in this paper is aimed at optimising the measurable cost of reworking/scrapping the off-specification items as well as the cost of adjusting manufacturing processes with the aim of reducing or eliminating rejected pieces. The adjustment of process specification in relation to customer specification is a strategy that can affect production and quality cost. Consideration for optimal production specification is one of the elements of the model presented in this paper. In the proposed model, the direct cost of poor quality has been represented by a symmetrical truncated loss function. We have considered investment to adjust the mean and variance of the process. A numerical example is presented to demonstrate how the model can work in a real-world setting.     

Enhanced photocatalytic performance of Fe-doped SnO2 nanoarchitectures under UV irradiation: synthesis and activity

A facile, sol–gel method has afforded highly crystalline, Fe-doped SnO₂ nanoarchitectures with efficient photocatalytic degradation of rhodamine B (RhB) under ultraviolet irradiation. The effects of iron modification to tin dioxide were investigated. The structural properties were characterized by powder X-ray diffraction, gas sorption (adsorption/desorption) techniques, scanning electron microscopy, high-resolution transmission electron microscopy, and energy dispersive X-ray spectroscopy (EDS). The photocatalytic activity of these materials was studied by examining the degradation of RhB with pure SnO₂ and each Fe modified sample (3 and 5 %), all annealed at 350 °C. Diffraction results reveal that the synthesized nanocrystals are ~3 nm in diameter. Gas sorption analyses detail high-specific surface areas (>330 m² g^?1). Electron microscopy studies illustrate the enhanced porosity brought on through annealing. EDS confirms the presence of Fe in the most active Fe-modified SnO₂ sample. It is found that the 5 % Fe-modified SnO₂ degrades RhB by more than half after 2 h.     

Electron microscopy investigations of metal-support interaction effects in M/Y2O3 and M/ZrO2 thin films (M=Cu,Ni)

Model systems of the clean and pure oxides Y₂O₃ and ZrO₂, as well as Cu/Cu₂O and Ni/NiO particles embedded in the respective oxides have been used to study the reduction behavior of the oxides and the eventually associated metal-support interaction effects in oxide-supported systems. Particular emphasis has also been given to the influence of the phase transformation in ZrO₂-containing systems on metal-support interaction. Whereas Y₂O₃ has been found to be an outstandingly structurally and thermally stable oxide even upon reduction in hydrogen up to 1073 K, ZrO₂ was found to undergo a series of phase transformations from amorphous ZrO₂ to polycrystalline tetragonal ZrO₂ (∼673 K) and subsequently to monoclinic ZrO₂ (above 873 K). Both phase transformations were found to be basically dependent on gas partial pressure and annealing rate. However, substantial reduction of the oxides did not take place during the phase transformations. In turn, both Cu- and Ni-containing systems were not observed to be substantially affected by any (strong) metal-support interaction effects such as encapsulation by sub-stoichiometric oxides or reductive formation of intermetallic phases, at least up to temperatures of 1073 K. Equally, for the ZrO₂-containing systems, also the phase transformations occurring at elevated temperatures did not cause structural or thermo-chemical alterations of the Cu or Ni-particles. Differences in the metal-support interaction between Cu- and Ni-particles have only been obtained in the structural “reference” systems, that is, if supported on SiO₂. Whereas Cu/Cu₂O particles on SiO₂ are basically unaffected by the reductive treatment at elevated temperatures, a Ni₃Si₂ intermetallic phase is formed if SiO₂-supported Ni/NiO particles are treated in hydrogen at 673 K and above.     

Evaluation of Antioxidant Compounds and Total Sugar Content in a Nectarine [Prunus persica (L.) Batsch] Progeny

Epidemiological studies suggest that consumption of fruit rich in phenolic compounds is associated with health-protective effects due to their antioxidant properties. For these reasons quality evaluation has become an important issue in fruit industry and in breeding programs. Phytochemical traits such as total phenolics, flavonoids, anthocyanins, L-ascorbic acid, sugar content and relative antioxidant capacity (RAC) were analyzed over four years in flesh fruit of an F1 population "Venus" × "Big Top" nectarines. Other traits such as harvesting date, yield, fruit weight, firmness, soluble solids concentration (SSC), pH, titratable acidity (TA) and ripening index (RI) were also determined in the progeny. Results showed high variability among genotypes for all analyzed traits. Total phenolics and flavonoids showed significant positive correlations with RAC implying that both are important antioxidant bioactive compounds in peaches. We found genotypes with enhanced antioxidant capacity and a better performance than progenitors, and in consequence the best marketability.     

Recent advances on ion-imprinted polymers

Selective recognition of metal ions is a real challenge for a large range of applications in the analytical field (from extraction to detection and quantification). For that purpose, ion-imprinted polymers (IIPs) have been increasingly developed during the last 15 years on the principle of molecularly imprinted polymers (MIPs). Those imprinted materials are designed to mimic the binding sites of biological entities and assure an improved recognition of the template species. The aim of this review is to give the current state of the art in the conception of IIPs from the components to the polymerization process. Some applications of those materials will be also discussed.     

Self-cleaning wool: effect of noble metals and silica on visible-light-induced functionalities of nano TiO2 colloid

This study intends to enhance the functionality of titanium dioxide (TiO₂) nanoparticles applied to wool fabrics under visible light. Herein, TiO₂, TiO₂/SiO₂, TiO₂/Metal, and TiO₂/Metal/SiO₂ nanocomposite sols were synthesized and applied to wool fabrics through a low-temperature sol–gel method. The impacts of three types of noble metals, namely gold (Au), platinum (Pt), and silver (Ag), on the photoefficiency of TiO₂ and TiO₂/SiO₂ under visible light were studied. Different molar ratios of Metal toTiO₂ (0.01, 0.1, 0.5, and 1%) were employed in synthesizing the sols. Photocatalytic efficiency of fabrics was analyzed through monitoring the removal of red wine stain and degradation of methylene blue under simulated sunlight and visible light, respectively. Also, the antimicrobial activity against Escherichia coli (E. coli) bacterium and the mechanical properties of fabrics were investigated. Through applying binary and ternary nanocomposite sols to fabrics, an enhanced visible-light-induced self-cleaning property was imparted to wool fabrics. It was concluded that the presence of silica and optimized amount of noble metals had a synergistic impact on boosting the photocatalytic and antimicrobial activities of coated samples. The fabrics were further characterized using attenuated total reflectance, energy-dispersive X-ray spectrometry, and scanning electron microscopy images.     

Investigations on tyrosinase activity in melanin-free ink from Sepia officinalis: potential for food proteins cross-linking

Protein modification via enzymatic cross-linking is an attractive way for altering food structure so as to create products with increased quality and nutritional value. In this study, enzymatic cross-linking of β-casein was performed by tyrosinase activity, from melanin-free ink from Sepia officinalis, which was monitored by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE) techniques. The melanin-free ink contains a strong tyrosinase activity with pH 7 and 58?°C as optima of pH and temperature, respectively. Such activity is stimulated by ferrous ions and strongly inhibited by Mn²⁺, EDTA, H₂O₂, arbutin, and p-coumaric acid. We also show that 2 Mercapto-ethanol (14?mM) quickly and completely inactivated sepia tyrosinase. The melanin-free ink exhibits a major protein on SDS–PAGE with an N-terminal sequence matching perfectly with an internal sequence of the sepia peroxidase. The zymogram confirmed the inactive state of this truncated protein and the presence of an active tyrosinase enzyme. Interestingly, this activity was able to cross-link the β-casein protein. The tyrosinase implication in reticulation was demonstrated by the addition of its inhibitors, with 2-mercaptoethanol being the most effective, followed by arbutin, p-coumaric acid, and hydrogen peroxide.