A Method for the Detection of Cryptosporidium parvum Oocysts in Milk Based on Microfiltration and Real-Time Polymerase Chain Reaction

A method for the detection of Cryptosporidium parvum oocysts in milk was developed on the basis of optimizing microfiltration and elution of the material from the filter, and using a previously developed highly sensitive downstream detection by real-time polymerase chain reaction. The method involves heating of milk to 40°C, microfiltration through a membrane microfilter made of a mixture of cellulose acetate and cellulose nitrate (pore size, 3.0 μm), elution of the material from the filter by a solution containing sodium pyrophosphate and Tween 80 in a shaker, rapid DNA extraction using a Chelex-based agent, and single-tube nested real-time PCR. The detection limit of the method is 10 C. parvum oocysts per 100 ml of milk. The developed method may be useful for specific and sensitive control of contamination of milk by C. parvum oocysts.     

UV-Light Absorption Properties of Cr-Doped Polyethyleneglycol (PEG)/γ-Glycidoxypropyltrimethoxysilane (GPTMS)/Chelated-Titanium Coating Materials Prepared by the Sol–Gel Process

New hybrid inorganic–organic glass coating materials, which contain polyethyleneglycol/γ-glycidoxypropyltrimethoxysilane/titanium(IV)-n-propoxide(2-methoxyethylacetoacetate)/chromium(III)nitrate [PEG/GPTMS/Ti(OR)(2-MEAA)/Cr³⁺] have been developed for UV-light absorption by using the sol–gel process. The effect of agitation time and temperature on UV-light absorption was investigated. The titanium complex was characterized by ¹H-NMR and FTIR spectroscopies. UV–Vis spectroscopy was used to investigate the optical properties of the coating materials. The results show that the coated glass has very low transmission in the UV region (300–400 nm) compared to the uncoated glass, especially at 150, 200, 250 and 300°C treatment temperatures after 1- and 18-hour agitation times. The UV-light transmission of the coated glass was not different from the uncoated glass between 80–100°C and 350–500°C.     

The influence of gamma irradiation on the immunoreactivity of gliadin and wheat flour

The gliadin fraction of wheat flour gluten is potentially responsible for an allergic reaction in individuals with a genetic predisposition to allergy. In order to study the influence of ionising radiation on the immunogenicity of gliadin, samples of commercial gliadin powder and wheat flour were irradiated with doses between 2.2 and 12.8 kGy. Ethanolic extracts (40% ethanol/water, v/v) of treated samples were analysed by enzyme-linked immunosorbent assay (ELISA) with monoclonal antibodies against ω-gliadin or polyclonal anti-gliadin antibodies and by immunoblotting after polyacrylamide gel electrophoresis. Irradiated gliadin samples show the increase in allergenicity measured by ELISA. A linear relationship between the immune response induced by irradiated gliadin and the applied radiation dose was observed. The increase in immunoreactivity was confirmed by immunoblot assays with sera containing anti-gliadin antibodies. Immunoreactivity of gliadin extracted from irradiated wheat flour was higher than the immune response of pure gliadin irradiated with the same dose. RP-HPLC was applied for the analysis of gliadin constituents after irradiation. The content of ω-gliadins in irradiated samples decreased with increasing radiation dose.     

Dynamic Field Test, System Identification, and Modal Validation of an RC Minaret: Preprocessing and Postprocessing the Wind-Induced Ambient Vibration Data

The investigation of dynamic response for civil engineering structures largely depends on a detailed understanding of their dynamic characteristics, such as the natural frequencies, mode shapes, and modal damping ratios. Dynamic characteristics of structures may be obtained numerically and experimentally. The finite-element method is widely used to model structural systems numerically. However, there are some uncertainties in numerical models. Material properties and boundary conditions may not be modeled correctly. There may be some microcracks in the structures, and these cracks may directly affect the modeling parameters. Modal testing gives correct uncertain modeling parameters that lead to better predictions of the dynamic behavior of a target structure. Therefore, dynamic behavior of special structures, such as minarets, should be determined with ambient vibration tests. The vibration test results may be used to update numerical models and to detect microcracks distributed along the structure. The operational modal analysis procedure consists of several phases. First, vibration tests are carried out, spectral functions are produced from raw measured acceleration records, dynamic characteristics are determined by analyzing processed spectral functions, and finally analytical models are calibrated or updated depending on experimental analysis results. In this study, an ambient vibration test is conducted on the minaret under natural excitations, such as wind effects and human movement. The dynamic response of the minaret is measured through an array of four trixial force-balanced accelerometers deployed along the whole length of the minaret. The raw measured data obtained from ambient vibration testing are analyzed with the SignalCAD program, which was developed in MATLAB. The employed system identification procedures are based on output-only measurements because the forcing functions are not available during ambient vibration tests. The ModalCAD program developed in MATLAB is used for dynamic characteristic identification. A three-dimensional model of the minaret is constructed, and its modal analysis is performed to obtain analytical frequencies and mode shapes by using the ANSYS finite-element program. The obtained system identification results have very good agreement, thus providing a reliable set of identified modal properties (natural frequencies, damping ratios, and mode shapes) of the structure, which can be used to calibrate finite-element models and as a baseline in health monitoring studies.     

Optimization of the vulcanization parameters for ethylene–propylene–diene termonomer (EPDM)/ground waste tyre composite using response surface methodology

The utilization of waste tyre in a green way would definitely mitigate the possible risks of the waste tyre accumulation. A green way to solution for the waste tyre problem is recycling. However, it is necessary to optimize the recycling process parameters to come up with the optimum conditions for the effective reuse of the waste tyre. In this study, response surface methodology (RSM) was used to model and optimize the parameters of curing of EPDM and waste tyre composite for the purpose of waste tyre recycling. EPDM with different loadings of ground waste tyre composites were prepared. Mechanical, thermal, and Soxhlet extraction tests were carried out for the samples. RSM was applied and process parameters were optimized. It was seen that the most effective parameter was the curing temperature. The optimal values of the parameters were determined as curing temperature of 172.1 °C, curing pressure of 15.0 MPa and ground waste tyre content of 14.8% by weight. To test the parameters determined from optimization study, the samples were prepared under optimum conditions, and it was shown that the samples prepared according to the optimum conditions have better thermal, mechanical, and curing properties. The results were heartening to pursue the waste tyre recycling option with a considerable amount of ground waste tyre content within the final composite material.     

Identification and Characterization of Phospholipids with Very Long Chain Fatty Acids in Brewer’s Yeast

Yeast lipids and fatty acids (FA) were analyzed in Saccharomyces pastorianus from seven breweries and in the dietary yeast supplement Pangamin. GC–MS identified more than 30 FA, half of which were very‐long chain fatty acids (VLCFA) with hydrocarbon chain lengths of ≥22 C atoms. Positional isomers ω‐9 and ω‐7 were identified in FA with C18–C28 even‐numbered alkyl chains. The most abundant ω‐7 isomer was cis‐vaccenic acid. The structure of monounsaturated FA was proved by dimethyl disulfide adducts (position of double bonds and cis geometric configuration) and by GC–MS of pyridyl carbinol esters. Ultra‐high performance liquid chromatography‐tandem mass spectrometry with negative electrospray ionization identified the phospholipids phosphatidylethanolamine, phosphatidylinositol and phosphatidylcholine, with more than 150 molecular species. Wild‐type unmutated brewer's yeast strains conventionally used for the manufacture of food supplements were found to contain VLCFA.     

The effect of microwave treatment on the immunoreactivity of gliadin and wheat flour

Commercial gliadins and wheat flour were exposed to microwaves at power distribution of 70, 200, and 500 W for different time periods to achieve a level of applied energy doses up to 150 kJ. Ethanolic extracts (40 vol.% ethanol/water) of microwave treated samples were analyzed by ELISA with the use of either monoclonal antibodies against -gliadin or polyclonal anti-gliadin antibodies and by electrophoresis followed by immunoblotting. A significant increase in reactivity, almost 210% over the untreated control sample, was observed for gliadins exposed to the energy dose of 40 kJ. Gliadins treated with higher energy doses showed a drop in an immune response independent of monoclonal or polyclonal antibodies used in ELISA. Gliadin fractions extracted from wheat flour treated with microwaves demonstrated similar immunoreactivity changes vs applied energy, although the maximum of reactivity appeared at 30 kJ. The increase in immune response of microwave irradiated gliadins was also confirmed by immunoblotting assay with the use of sera of patients susceptible to wheat flour allergy. Reversed phase HPLC elution profiles of treated gliadins showed that the content of all gliadin fractions in microwave treated samples decreased with the increase of the dose of applied energy.     

Turing Interrogative Games

The issue of adequacy of the Turing Test (TT) is addressed. The concept of Turing Interrogative Game (TIG) is introduced. We show that if some conditions hold, then each machine, even a thinking one, loses a certain TIG and thus an instance of TT. If, however, the conditions do not hold, the success of a machine need not constitute a convincing argument for the claim that the machine thinks.