The Effect of Moisture Content on the Conversion of Ergosterol to Vitamin D in Shiitake Mushrooms

The distribution of ergosterol in different parts of shiitake mushrooms was studied in order to optimize the conversion of ergosterol to vitamin D₂ during drying. The effect of moisture on the conversion of ergosterol to vitamin D₂ was also investigated by adjusting the moisture content of fresh mushrooms to different levels in a large vacuum desiccator and subjecting them to UV irradiation at 290-320 nm wavelength, for 2 h. The moisture, ergosterol and vitamin D₂ contents were determined using standard procedures. It was found that the ergosterol content on a dry matter basis of fresh shiitake mushroom was highest in the gills (10.6 ± 0.99 mg/g DM), followed by the cap or pileus (5.34 ± 0.64 mg/g DM) and was least in the stalk or stipe (2.97 ± 0.56). The moisture content had a marked influence on the conversion of ergosterol to vitamin D₂, the best conversion taking place at a moisture content of about 70% on a wet basis.     

Aging, expertise, and narrative processing.

In a study of how aviation expertise influences age differences in narrative processing, young and older pilots and nonpilots read and recalled aviation and general narratives. They chose referents for sentences referring to a protagonist or minor character mentioned 1 sentence (recent character) or 3 sentences (distant character) before this target sentence. All groups chose referents less accurately for sentences about distant and minor characters than about recent and protagonist characters, perhaps because these referents were less likely to be in working memory. Young readers and pilots were more accurate for distant and minor character target sentences in aviation narratives and recalled aviation narratives more accurately. Expertise did not reduce age differences. Expertise differences may reflect decreased demands on working memory capacity, and age declines may reflect reduced capacity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Determining hearing threshold from brain stem evoked potentials.Optimizing a neural network to improve classification performance

Feed-forward neural networks in conjunction with back-propagation are an effective tool to automate the classification of biomedical signals. Most of the neural network research to date has been done with a view to accelerate learning speed. In the medical context, however, generalisation may be more important than learning speed. With the brain stem auditory evoked potential classification task described in this study, the authors found that parameter values that gave fastest learning could result in poor generalisation. In order to achieve maximum generalisation, it was necessary to fine tune the neural net for gain, momentum, batch size, and hidden layer size. Although this maximization could be time consuming, especially with larger training sets, the authors' results suggest that fine tuning parameters can have important clinical consequences, which justifies the time involved. In the authors' case, fine tuning parameters for high generalisation had the additional effect of reducing false negative classifications, with only a small sacrifice in learning speed     

Alternative fatty food simulants for migration testing of polymeric food contact materials.

The amounts of substances migrating from plastics into foodstuffs with high fat contents are in most cases higher than in foodstuffs with water contents. This increase in migration commonly is due to the higher solubility of the migrating organic compounds in fat compared to water. The increase in migration is not necessarily due to an increase in the substance's diffusion coefficient due to interactions between the fat and the plastic as is often assumed. Ethanol is a good simulant for fatty foods because it has little interaction with many plastics, e.g. polyolefins, migrants are readily soluble in it, and because it is easy to work with analytically. The utilizable limits of ethanol and ethanol/water mixtures as food simulants are developed from the physical background of diffusion. The use of ethanol and ethanol/water mixtures is supported by published experimental migration results.     

Ion-Pairing of Dyclonine with Dyes

This potential for ion-pairing between dyclonine, a local anesthetic, and pharmaceutical dyes commonly used in liquid pharmaceutical formulations was examined. Occurrence of ion-pairing at a pH of 3 was confirmed by shift of the absorption maximum of all five sulfonate-containing dyes, and by measurements of octanol/water partition coefficient and surface tension. There was also an increase in the uptake of dyclonine by phosphatidylcholine liposomes in the presence of a dye (tartrazine) at pH 3 but not at pH 7, where the uncharged anesthetic is dominant.     

Experience of operating VVBK-500 high-voltage switches

Power Technology and Engineering -     

Feeding differently processed soya bean. Part 2. An assessment of haematological responses in the chicken.

The use of differently processed soya bean as a major source of dietary protein was evaluated in a haematological study using broiler chickens in which groundnut cake (GNC), raw soya bean (RSB), roasted soya bean (RtSB), cooked soya bean (CSB) and soya bean oil cake (SBC) were fed on equi-protein basis. The results showed that: 1. Red blood cell (RBC) count and haemoglobin content of blood significantly (P less than 0.05) increased in chicks fed RSB relative to the other soya bean diets. Feeding differently processed soya bean significantly (P less than 0.05) influenced mean cell haemoglobin (MCH) and mean corpuscular volume (MCV) while the mean corpuscular haemoglobin concentration (MCHC) was not significantly influenced. 2. Both the total white blood cell (WBC) count and the monocytes were significantly (P less than 0.05) influenced by the dietary treatments. Chicks fed processed soya bean generally had higher number of monocytes. 3. Physical properties determined were specific gravity and erythrocyte sedimentation rate. The latter was significantly (P less than 0.05) lower in all the processed soya bean-fed chicks. 4. Minerals determined in blood were Na, K, Ca, Mg, Fe, Cu and P. Of all these, chicks fed RSB had significantly (P less than 0.01) lower levels of blood Mg and marked decrease in Ca.