Effectiveness of high pressure processing on the hygienic and technological quality of porcine plasma from biopreserved blood

The effects of a high hydrostatic pressure (HHP) treatment (450MPa, 15min at 20°C) on both the microbiological quality and the functional properties of plasma from biopreserved porcine blood were evaluated. Blood was inoculated with Enterococcus raffinosus-PS99 (10(7)ufcmL(-1)) and stored at 5°C. After 72-h storage, bacterial counts in inoculated samples decreased by 52, 70, 81 and more than 99% for coliforms, Pseudomonas spp, hemolytic and proteolytic bacteria, respectively. Counts of these bacterial groups were undetectable in the final product after pressurization, whereas total lactic acid bacteria were detected at levels up to 10(2)ufcmL(-1). Gelling, foaming and emulsifying properties of the plasma proteins were not noticeably affected by HHP. The results show that it is possible to obtain high-quality and microbiologically stable blood derivatives as functional ingredients, by combining biopreservation and HHP.     

Quality assurance of PASADENA hyperpolarization for 13C biomolecules

Object  Define MR quality assurance procedures for maximal PASADENA hyperpolarization of a biological ¹³C molecular imaging reagent. Materials and methods  An automated PASADENA polarizer and a parahydrogen generator were installed. ¹³C enriched hydroxyethyl acrylate, 1-¹³C, 2,3,3-d₃ (HEA), was converted to hyperpolarized hydroxyethyl propionate, 1-¹³C, 2,3,3-d₃ (HEP) and fumaric acid, 1-¹³C, 2,3-d₂ (FUM) to hyperpolarized succinic acid, 1-¹³C, 2,3-d₂ (SUC), by reaction with parahydrogen and norbornadiene rhodium catalyst. Incremental optimization of successive steps in PASADENA was implemented. MR spectra and in vivo images of hyperpolarized ¹³C imaging agents were acquired at 1.5 and 4.7 T. Results  Application of quality assurance (QA) criteria resulted in incremental optimization of the individual steps in PASADENA implementation. Optimal hyperpolarization of HEP of P = 20% was achieved by calibration of the NMR unit of the polarizer (B ₀ field strength ± 0.002 mT). Mean hyperpolarization of SUC, P = [15.3 ± 1.9]% (N = 16) in D ₂O, and P = [12.8 ± 3.1]% (N = 12) in H ₂O, was achieved every 5–8 min (range 13–20%). An in vivo ¹³C succinate image of a rat was produced. Conclusion  PASADENA spin hyperpolarization of SUC to 15.3% in average was demonstrated (37,400 fold signal enhancement at 4.7 T). The biological fate of ¹³C succinate, a normally occurring cellular intermediate, might be monitored with enhanced sensitivity.     

Unsafe storage of poisons in homes with toddlers

BACKGROUND: The objective of this project was to assess the current nature and level of preventive actions that parents take to avoid unintentional poisoning among toddlers (11-18 months old). METHODS: In 2004, we conducted a cross-sectional observational survey with self-administered questionnaires among parents with toddlers (n=1,722). Data were obtained on storage locations of medicines and cleaning products and supervision of children. RESULTS: Overall, 50.1% of the toddlers were exposed to unsafe storage of possible poisonous products in the home. Parents were more likely to store medicines safely than cleaning products, and products were most often stored unsafely in the kitchen, where children were left unattended most often (69%). Households with one child were associated with unsafe storage of both medicines and cleaning products. Lower educational level of the mother and unemployment of the mother were both associated with safe storage of medicines. Mother's ethnicity, the child's ability to walk, and the education level of the father were associated with storage of cleaning products. CONCLUSIONS: The results of this study are an important first step for the development of effective interventions to reduce unintentional poisoning in toddlers' homes.     

Estimation of measurement uncertainties using virtual fringe projection technique

One of the main tasks of the quality test is the inspection of all relevant geometric parts related to the predefined tolerance range, whereas the uncertainty of measurement has to be less than the tolerance range. The reachable uncertainty of measurement can be determined using method A of the ISO Guide to the Expression of Uncertainty in Measurement (GUM), which is expensive and time consuming and has to be carried out for each individual metrologic case. Furthermore, it is possible to check the suitability of the measurement system for the planned inspection using virtual measurement techniques and therewith to reduce the time and money spent. This means that the uncertainty of measurement is estimated using method B of the GUM. In this paper, a virtual fringe projection system is used for the estimation of the uncertainty of measurement, which is compared with the uncertainty of measurement determined with a real measurement system using method A of the GUM. With the presented method, it is possible to calculate an optimal measurement position within the measurement volume, based on a minimum uncertainty of measurement. Thereby, the influence of the operator related to the uncertainty can be significantly reduced.     

Polycythemia due to obstructive sleep apnea in a patient on hemodialysis

Both anemia and sleep disordered breathing are common in patients with dialysis‐dependent stage 5 chronic kidney disease. Erythrocytosis resulting from obstructive sleep apnea (OSA) is rare in the general population and has never been described in the hemodialysis population. We present a case of asymptomatic isolated erythrocytosis and elevated serum erythropoietin level in an otherwise well and previously erythropoietin‐dependent chronic hemodialysis patient with chronic kidney disease secondary to ischemic nephropathy. There was no history or symptoms of cardio‐pulmonary or hepatic diseases nor any relevant family history. Screening work‐up for malignancies was negative. The clinical history was highly suggestive of OSA and severe OSA (respiratory disturbance index of 59) was confirmed by polysomnographic studies. Successful treatment of the OSA with continuous positive airway pressure resulted in permanent stabilization of the hemoglobin to levels below 13 g/dL without the need for repeated phlebotomies and in dramatic lowering of serum erythropoietin levels. To our knowledge, this is the first case of OSA mediated erythrocytosis in a dialysis patient documented in the literature.     

Critical Aspects of Alloying of Sintered Steels with Manganese

This study examines the sintering behavior and properties of Fe-0.8Mn-0.5C manganese powder metallurgy steels. The study focuses on the influence of mode of alloying—admixing using either high-purity electrolytic manganese or medium carbon ferromanganese as well as the fully prealloying of water-atomized powder. Three main aspects were studied during the whole sintering process—microstructure development, interparticle necks evolution, and changes in the behavior of manganese carrier particles during both heating and sintering stages. The prealloyed powder shows considerable improvement in carbon homogenization and interparticle neck development in comparison with admixed materials. The first indication of pearlite for the fully prealloyed material was registered at ~1013 K (740 °C) in comparison with ~1098 K (825 °C) in the case of the admixed systems. The negative effect of the oxidized residuals of manganese carrier particles and high microstructure inhomogeneity, which is a characteristic feature of admixed systems, is reflected in the lower values of the mechanical properties. The worst results in this respect were obtained for the system admixed with electrolytic manganese because of more intensive manganese sublimation and resulting oxidation at lower temperatures. According to the results of X-ray photoelectron spectroscopy and high-resolution scanning electron microscopy and energy dispersive X-ray analyses, the observed high brittleness of admixed materials is connected with intergranular decohesion failure associated with manganese oxide formation on the grain boundaries.     

Testing of self‐similarity and helical symmetry in vortex generator flow simulations

Vortex generators (VGs) are used increasingly by the wind turbine industry as flow control devices to improve rotor blade performance. According to experimental observations, the vortices generated by VGs have previously been observed to be self‐similar for both the axial (u_z) and azimuthal (u_θ) velocity components. Furthermore, the measured vortices have been observed to obey the criteria for helical symmetry. These are powerful results, as it reduces the highly complex 3‐D flow to merely four parameters and therefore significantly facilitates the modeling of this type of flow, which in a larger perspective can assist in parametric studies to increase the total power output of wind turbines. In this study, corresponding computer simulations using Reynolds‐averaged Navier–Stokes equations have been carried out and compared with the experimental observations. The main objective is to investigate how well the simulations can reproduce these aspects of the physics of the flow, i.e., investigate if the same analytical model can be applied and therefore significantly facilitate the modeling of this type of flow, which in a larger perspective can assist in parametric studies to increase the total power output of wind turbines. This is especially interesting since these types of flows are notoriously difficult for the turbulence models to predict correctly. Using this model, parametric studies can be significantly reduced, and moreover, reliable simulations can substantially reduce the costs of the parametric studies themselves. Copyright © 2015 John Wiley & Sons, Ltd.     

High-throughput approach to the catalytic combustion of diesel soot

A methodology for the evaluation of diesel soot oxidation catalysts by high-throughput (HT) screening was developed. The optimal experimental conditions (soot amount, catalyst/soot ratio, type of contact, composition and flow rate of gas reactants) ensuring a reliable and reproducible detection of light-off temperatures in a 16 parallel channels reactor were set up. The temperature profile measured in the catalyst/soot bed under TPO conditions when the exothermic combustion of soot takes place was shown to provide an accurate measurement of the ignition. Its reproducibility and relevance were checked. The results obtained with a reference noble metal free catalyst (La_0.8Cr_0.8Li_0.2O₃ perovskite) agree very well with literature data. Qualitative mechanistic features could be derived from these experiments, stressing the likely limiting step of oxygen transfer from catalyst surface to soot particulates to ignite the soot combustion. Ceria material was shown to be more appropriate than perovskite one. From an HT screening of a large diverse library (over 100 mixed oxides catalysts) under optimized conditions, about 10 new formulations were found to perform better than selected noble metal free reference materials.     

Polymer/Clay Nanocomposites: Influence of Ionic Strength on the Structure and Adhesion Characteristics in Multilayered Films

The aim of the present contribution is to understand how ionic strength, brought by the addition of salt to laponite/PEO nanocomposite dispersions, influences the texture and adhesion characteristics at nano‐ and microscales in multilayered nanocomposite films prepared from such dispersions. At the nano‐scale, SAXS and XRD measurements indicated that the clay platelets orient parallel to the film plane and that the polymer chains intercalate the clay platelets regardless of salt addition. A gradual transition from an agglomerated structure, containing polymer‐rich and clay‐rich domains, to a fine‐balanced structure with smaller distinct details without excess PEO was observed, via AFM, on the exposed edges of cryo‐microtomed films with increasing ionic strength.