Engineered anisotropic microstructures for ultrathin-layer chromatography.

The strong dependence of separation behavior on ultrathin-layer chromatography (UTLC) stationary phase microstructure motivates continued UTLC plate design optimization efforts. We fabricated 4.6-5.3 mum thick normal phase silica UTLC stationary phases with several types of in-plane macropore anisotropies using the glancing angle deposition (GLAD) approach to engineering nanostructured thin films. The separation behaviors of two new media, isotropic vertical posts and anisotropic bladelike films, were compared to that of anisotropic chevron media. Channel-like structures within the anisotropic media introduced preferential mobile phase flow directions that could be exploited to give separation tracks diagonal to the development direction. Extraction of chromatograms from these angled tracks required the development of a new analytical approach that involved a commercial flatbed film scanner and custom numerical image analysis software. GLAD stationary phase performance was quantified using the Dimethyl Yellow dye separated from a lipophilic dye mixture over migration distances less than approximately 10 mm. The limits of detection were 10 +/- 4 ng for the vertical posts and 11 +/- 3 ng for the bladelike media. We obtained theoretical plate heights that varied with film microstructure between 12 and 28 mum. Unoptimized separation performance was comparable to that of other planar chromatography media. Macropore anisotropies engineered by GLAD may expand the capabilities of future UTLC stationary phases.

Examining the role of informal interpretation in medical interviews.

A linguistic barrier between healthcare professional and patient is a challenging experience for both parties. In many cases, the absence of formally trained medical interpreters necessitates that an informal interpreter, drawn from the immediate environment, be used to facilitate communication. While the presence of an interpreter in a medical interview raises many questions about the effectiveness of the communication between healthcare professional and patient, it also gives rise to new speculations revolving on patient rights, medical ethics and patient privacy. In this article we examine the concept of communication competency in medical interviews, as well as translation theory, and link these theories to Western medical ethics in order to identify potential areas in which informal interpretation could impact on the patient.

Factors which affect blood variables of slaughtered cattle.

Blood was obtained at an abattoir from 4 groups of cattle. The first group was slaughtered in a conventional way, the second and third were subjected to shechita slaughter with or without the application of the captive bolt immediately after the cutting of the throat, and the fourth group of cattle was subjected to a period of recumbency prior to conventional slaughter. Blood samples were analysed for concentrations of catecholamines, cortisol, glucose, lactate and total lipids. The haematocrit and osmolarity was also determined. There were no major differences in the blood variables of cattle subjected to conventional slaughter and those of cattle which had been subjected to a period of recumbency prior to conventional slaughter. Plasma catecholamine concentrations in cattle subjected to shechita slaughter without the application of a stun, were significantly elevated when compared to any of the other groups. It was concluded that postural changes have very little effect on the blood variables, but that the application of a stun after the throat has been cut in shechita slaughter abolishes the increases in blood variables associated with shechita in the absence of stunning.