An immunoassay for ochratoxin A without the mycotoxin

Phage display peptide libraries allow the selection of new molecules capable of mimicking the structural and functional features of native proteins or chemicals. This technology can be applied to developing new reagents, which may serve as the surrogate of the original objects. In order to screen peptides capable of mimicking ochratoxin A (OTA) in the interaction with anti-OTA monoclonal antibody (McAb) and establish the immunoassay for OTA, an anti-OTA McAb was used as the target for panning-elution selection from a phage random seven-peptide library. After four rounds of panning, 11 phages were found to be able to mimic OTA in binding with the antibody. Enzyme-linked Immunosorbent Assay (ELISA) for detecting OTA was established with the phages. In the most sensitive assay, the linear range of the inhibition curve was 200–8000 pg/ml; the detection limit was 150 pg/ml. The inserted peptide sequences were deduced by DNA sequencing. The common amino acid residue sequence was IR(V)PMV(L)XX (X is any amino acid residues), which was verified by two synthesized peptides. The results demonstrated that those phage peptides could be used as the surrogate of OTA to establish the immunoassay.     

New application of hierarchical zeolite in life science: Fast trapping nitrosamines in artificial gastric juice by alkaline-tailored HZSM-5

To open a new application of zeolite in life science, hierarchical zeolites were prepared for the struggle of anti-cancer. Adsorption of N-nitrosopyrrolidine (NPYR), one of the volatile nitrosamines, by alkaline-treated MFI zeolite in artificial gastric juice with pH of 1.2 was investigated. Through the creation of mesopores in zeolite to fasten mass transport, all alkaline-treated samples exhibited higher adsorptive capability than HZSM-5 zeolite, and the equilibrium adsorption data could be fitted to the Freundlich equation.     

Bovine lactoferrin pepsin hydrolysate exerts inhibitory effect on angiotensin I-converting enzyme-dependent vasoconstriction

The inhibitory effect of a pepsin hydrolysate of bovine lactoferrin (LFH) on angiotensin I-converting enzyme (ACE) has been examined using in vitro and ex vivo functional assays. In vitro assays showed a LFH inhibitory effect on ACE activity with an IC₅₀ value of 0.95±0.06 mg mL⁻¹. Ex vivo functional assays using rabbit carotid artery segments showed a LFH inhibitory effect on ACE-dependent angiotensin I-induced contraction, but not on angiotensin II-induced contraction, suggesting that the effect of LFH is not due to antagonism of receptors for angiotensin II. LFH was shown to possess ACE inhibitory effect with potential to modulate hypertension, although the possible inhibitory effect of LFH on angiotensinases deserves further research.     

Measurement of permeability of continuous filament mat glass–fibre reinforcements by saturated radial airflow

The measurement of fibre reinforcement permeability is important for the understanding, optimisation and modelling of RTM and resin infusion processes. This work investigates the use of a saturated radial air flow experiment for measuring the permeability of continuous filament mat (CFM), which is a common reinforcement type used for industrial RTM parts. The use of air, rather than liquid resin, is cleaner, quicker and potentially easier to control. The paper considers the problems inherent in using a compressible fluid, instead of a liquid, for the measurement of permeability, and the requirements for maintaining laminar flow. It describes the instrumentation used for flow and pressure measurement, and the effect of varying flow rate. Results compare favourably with published permeability values based on liquid flow experiments, and are independent of flow rate within the range of values investigated.     

An electrocatalyst for methanol oxidation based on tungsten trioxide microspheres and platinum

Tungsten trioxide microspheres of 2–4 μm diameter have been prepared by controlled oxidation of tungsten carbide microspheres. These microspheres are characterized by XRD, SEM, and HRTEM. The microspheres are made of WO₃ nanoparticles with an average diameter of around 15 nm. Platinum supported on these WO₃ microspheres exhibits higher and stable electrocatalytic activity for methanol oxidation by a factor of around two, than commercial 20 wt.% Pt–Ru/Vulcan-XC72 carbon and 20 wt.% Pt–Ru/carbon microspheres even without Ru. The higher activity is attributed to the better tolerance to carbon monoxide of the Pt/WO₃ catalyst. These Pt/WO₃ microspheres appear to be a promising alternative anode material for direct methanol fuel cells. They replace Ru entirely and save a substantial amount of Pt in the Pt–Ru electrode that is presently employed in fluel cells.     

Failure estimation of TIG butt-welded Inco718 sheets at 620 °C under creep and plasticity conditions

This paper describes the creep behaviour of plain, notched and welded specimens machined from Inco718 sheet material. The Inco718 welded sheets experience out of plane distortion due to the welding process and these sheets also have weld beads with sharp fillet radii. Both the out of plane distortion and the fillet radii result in high stress concentrations and local plastic deformations which can significantly affect the failure life of the sheets, at high temperature, under creep conditions. Experimental creep testing using plain, notched and welded specimens was carried out at 620 °C. From the test data, the plasticity behaviour and the creep and damage constitutive equations were obtained for the material. On this basis, failure predictions of the welded sheets, based on continuum damage mechanics modelling, were conducted, using the finite element method. The results obtained are compared with the corresponding experimental data and the applicability of the method for predicting failure lives is discussed.     

A latent Gaussian model for multivariate consumption data

We propose a multivariate statistical model for individual consumption of multiple food types, to provide a more objective basis for exposure assessment from chronic consumption. Intake of each type of food is modelled by a latent Gaussian variable, where intake is zero if the latent variable is below a threshold, and otherwise is a monotonically increasing function of the latent variable. Further, we use a Factor Analysis model to describe the association in intakes between different foods. This reduces the number of parameters to be estimated and aids interpretation. The method is illustrated using data from the Dietary and Nutritional Survey of British Adults, 1986–1987.     

Next generation polymers of intrinsic microporosity with tunable moieties for ultrahigh permeation and precise molecular CO2 separation

Polymers of intrinsic microporosity (PIMs) with high free volumes have been synthesized by incorporating contorted rigid moieties into polymers backbones. Despite their many appealing properties, membranes made of these polymers have not been used industrially because of their fast physical aging. The unprecedented CO₂ permeability and satisfactory CO₂/N₂ and CO₂/CH₄ selectivity of PIMs have led to establishing the new 2019 upper bounds for the gas mixtures. This article reviews recent advances in the field of PIM-based membranes. It discusses polymer synthesis strategies to modify PIM structures such that the resulting membranes have improved CO₂ separation performance and lower physical aging. The strategies include the use of monomers with suitable side chains, kinked moieties, and stable structures.     

Integration of high and low field 1H NMR to analyse the effects of bovine dietary regime on milk metabolomics and protein-bound moisture characterisation of the resulting mozzarella cheeses during ripening

The influence of dairy cow feeding regime was investigated using ¹H nuclear magnetic resonance (NMR). Two different NMR analytical systems were deployed: high field ¹H NMR to investigate the influence on milk metabolomics and low field NMR to characterise proton relaxation linked to changes in the state of mozzarella cheese moisture during ripening. The metabolomics results showed that grass-based feeding increased the concentration of a biological marker that signifies near-organic milk production conditions. On the other hand, the investigation of cheese moisture distribution showed that grass-based diets reached final moisture partitioning in a shorter time, which implied the formation of a more compact protein structure in the cheese matrix. These results indicate that pasture-based dairying may be differentiated in terms of the provenance of milk produced along with the accrual of additional benefits during ripening of the resulting mozzarella cheeses.