Characterization of microflora in homemade semi-hard white Zlatar cheese

The Zlatar cheese belongs to the group of traditionally homemade cheeses, which are produced from nonpasteurized cow's milk, without adding of any bacterial starter culture. Changes were followed in lactic acid bacteria population and chemical composition during the ripening period of cheese up to 60 days. Results showed that the percentage of lactic acid cocci was higher in raw milk and one day old cheese and their percentage was gradually decreasing, whereas the number of lactobacilli was increasing. After 30 days of cheese ripening the number of cocci increased again, reaching the number of lactobacilli. The results of API 50 CH system and rep-PCR analysis showed that Lactobacillus paracasei subsp. paracasei, Lactobacillus brevis, Lactococcus lactis subsp. lactis, Enterococcuus faecium and Enterococcus faecalis were the main groups present during the ripening of Zlatar cheese. Results revealed that in older cheeses (45 and 60 days old) enterococci were the main group present. It was also demonstrated that 57 isolates showed antimicrobial activity. The number of bacteria showing antimicrobial activity slowly decreased during the ripening period and in samples of 60 days old cheese producers of antimicrobial activities were not detected.     

TemplateTagger v1.0.0: A template matching tool for jet substructure

TemplateTagger is a C++ package for jet substructure analysis with Template Overlap Method. The code operates with arbitrary models within fixed-order perturbation theory and arbitrary kinematics. Specialized template generation classes allow the user to implement any model for a decay of a boosted heavy object. In addition to Template Overlap, the code provides ability to calculate other template shape and energy flow observables. We describe in detail the structure of the package, as well as provide examples of its usage.     

Supercritical CO2 extraction of Helichrysum italicum: Influence of CO2 density and moisture content of plant material

Kinetics and selectivity of supercritical carbon dioxide (SC CO₂) extraction of Helichrysum italicum flowers were analyzed at pressures in the range of 10-20 MPa and temperatures of 40 °C and 60 °C (density of SC CO₂ from 290 to 841 kg/m³) and also at 10 MPa and 40 °C using flowers with different moisture contents (10.5% and 28.4%). Increased moisture content of H. italicum flowers resulted in enchased solubility of solute enabling decrease of SC CO₂ consumption necessary for achieving desired extraction yield. The most abundant compounds in the supercritical extracts are sesquiterpenes and waxes while monoterpenes and sesquiterpenes are the main constituents of essential oil obtained by hydrodistillation. The optimal set of working parameters with respect to extraction yield, SC CO₂ consumption and chemical composition of extract were defined related to moisture content of raw material and SC CO₂ density.     

Improved Push–Pull Polarization Modulation Using Coupled Quantum-Well Structures

Recently, we proposed a push-pull polarization-modulation scheme based on multiple repetitions of two InGaAlAs-InAlAs coupled quantum-well (CQW) structures. Additional numerical simulations showed one of the two CQW structures to be quite sensitive to layer thickness and compositional variations. Consequently, it would be challenging to reliably grow polarization modulators using this structure. Here, using the effective-mass envelope-function approximation, we design a more robust CQW structure to replace the sensitive one, and we also make improvements to the less sensitive of the two original structures     

Composition and radical‐scavenging activity of Thymus glabrescens Willd. (Lamiaceae) essential oil

BACKGROUND: Knowledge about the chemical and therapeutic properties of Thymus glabrescens Willd. (Lamiaceae) is scarce and inconsistent. Therefore the main objectives of this study were to determine the yield and chemical composition of essential oils from wild‐growing T. glabrescens populations, to assess their radical scavenging activity and to correlate the results with published data in order to deduce which components are responsible for the activity. RESULTS: The plant material yielded between 4.0 and 8.0 mL kg^?1 of essential oil. All samples contained considerable but variable concentrations of thymol (22.3–55.1%), depending on the source. Radical‐scavenging activities of the oils were estimated by 1,1‐diphenyl‐2‐picrylhydrazyl free radical (DPPH) assay against butylated hydroxytoluene (BHT) and thymol as positive controls. The observed activities (IC₅₀ values ranged from 94 to 230 µg mL^?1) were strongly influenced by thymol concentration, as verified by rapid screening for DPPH radical‐scavenging activity on thin layer chromatography (TLC) plates and regression analysis. CONCLUSION: These results represent the first report on the free radical‐scavenging activity of T. glabrescens essential oil and one of the first comprehensive reports on its composition. Thymus glabrescens could be used in the food industry for seasoning purposes or for preserving processed foods from oxidative degradation. Copyright © 2008 Society of Chemical Industry     

Fourier-plane Characteristics of a Liquid-crystal Light Valve

Abstract

A lack of symmetry in the intensities of the plus and minus diffraction orders in the output Fourier plane of a liquid-crystal light valve has been observed. Measurement results and an intuitive discussion of this effect are presented.     

Qualitative and quantitative analysis of bovine milk adulteration in caprine and ovine milks using native-PAGE

Native-PAGE (polyacrylamide gel electrophoresis) was used for the simultaneous qualitative and quantitative analysis of bovine milk adulteration in caprine and ovine milk using whole milk samples as well as their whey protein fraction. Quantification was based on measuring band intensity of bovine β-lactoglobulins in all milk mixtures and bovine α-lactalbumin in caprine/bovine milk blends. Linear relationships were established between the band intensity of bovine β-lactoglobulins and α-lactalbumin vs. volume percentage of added bovine milk in all milk analysed, with the correlation coefficient from 0.9950 to 0.9998. These correlations enabling the quantification of bovine milk percentage within the wide range from 3% or 5% to 90% in caprine/bovine and ovine/bovine milk blends, respectively. The differences between the actual percentages of bovine milk present in the adulterated milk samples and those calculated using the regression lines were less than or equal to 5% for all samples. This method offers a rapid determination combined with unequivocal identification of the bovine whey proteins in almost every caprine/bovine or ovine/bovine milk mixtures.     

Automated proof inspection of turbine blades

The first article inspection of cast turbine blades is on the critical path of a new aeroengine. The current methods used are open to automation using CMM's and non-contact gauges to reduce lead times. A graphics system is discussed which allows modelling of the blade and Computer-Aided Part Programming of CMM's to produce a Neutral Data File for post processing. Once measured on the CMM the actual blade is modelled and bestfitted to the design intent. This allows subsequent error analysis to be carried out. Such a system is essential to make sense of large amounts of co-ordinate data and storage of dimensional variation at stages in the manufacturing process.     

Efficient registration of NURBS geometry

The paper presents an implementation of free-form surface registration in relation to inspection of engineering components, defined as NURBS. Registration is principally performed through the Iterative Closest Point (ICP) method. The time-critical step in ICP was found to be the determination of the closest points on NURBS to a given point in space. Significant speed improvements were achieved through the adoption of a dual surface representation, involving approximation of NURBS entities by a polyhedral mesh. A criterion for sufficient polyhedral approximation was derived and implemented, producing encouraging results. Original solutions are suggested in order to further improve the computational speed. Extensive testing has been carried out, showing that the proposed registration method handles a full six degrees of freedom and achieves global convergence. Performance of the implemented algorithms is discussed with reference to registration of a turbine blade airfoil.