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Objectives: Carotid intima-media thickness (CIMT) is a surrogate marker of subclinical atherosclerosis and a predictor of cardiovascular events. Few studies in Africa have evaluated CIMT and its associations in people with type 2 diabetes mellitus. This study measured CIMT in a sample of mainly black South African patients with type 2 diabetes mellitus, and evaluated the association of demographic and clinical risk factors with CIMT.Design: Cross-sectional study.Setting: Kafalong Hospital, a large community hospital in Pretoria that mainly serves an urban black community.Subjects: Patients with type 2 diabetes mellitus.Outcome measures: We evaluated clinical, biochemical and CIMT ultrasound measurements in a standardised fashion.Results: In 185 patients, the univariate significant predictors of mean far-wall CIMT were age [beta 0.007 (standard error 0.001)], systolic blood pressure [beta 0.001 (standard error 0.000)] and inverse serum creatinine [beta -8.15 (standard error 3.23)]. Low-density lipo...

Available techniques for diagnosis and evaluation of right ventricular (RV) function are limited. In patients with arrhythmogenic right ventricular dysplasia (ARVD) it is of great importance to assess RV wall motion and function for diagnosis, prognosis and treatment. Contrast echocardiography and videodensitometry can be used to illustrate regional and global RV hemodynamics. The authors investigated patients with ARVD and healthy volunteers by this method. An off-line analysis system was used for calculation of time intervals and indices of contrast dynamics in different regions of the right ventricle. The data were also color-coded to illustrate, in one single image, the dynamic process of the contrast. The RV wall motion was also assessed by a visual score system. The patient group showed longer time intervals for the processing of the contrast in the right ventricle than the healthy group. The color pattern for the whole process showed regional disturbances in the patient group which corresponded to the wall motion abnormalities as compared to the normals. Color-coded contrast echocardiography with videodensitometry quickly and easily demonstrated disturbances in filling and elimination patterns as signs of abnormal RV function, both regional and global, in patients with ARVD compared to healthy controls.

Fluorescence spectroscopy is a powerful tool for the study of the reactivity of chemical and biological systems The fluorescence spectrum, the fluorescence quantum yield, and the fluorescence lifetime of a chromophore depend on its microenvironment and the solute-solvent interactions Fluorescence lifetimes also depend on the kinetics of possible chemical reactions Fluorescence measurements in the time domain thus provide detailed information about intraand inter-molecular photophysical and photochemical processes During the past 30 years the development of laser sources and ultrafast techniques has opened new ways for the study of the fluorescent excited states of molecules in the nano-, pico-, and femtosecond time range When analyzing the rise and the decay (often multi-exponential) of their fluorescence intensity as a function of time, the pre-exponential factors and the fluorescence time constants have to be determined accurately after a careful deconvolution using a computer-based algorithm Several techniques are used: phase modulation spectroscopy with a modulated laser pump source on a time scale comparable to the decay times of interest, time-correlated single photon counting under picosecond laser excitation (alternatively nanosecond flashlamp excitation), ultra-fast streak cameras designed for the conversion of time dependent light emission into distance dependent electron impact on a phosphor screen Because a sufficient resolution is not accessible with those techniques for the measurement of fast decays in the 50 fs-100 ps range, fluorescence up-conversion in nonlinear optical crystals is the technique of choice.

SUMMARY Two computer- and image-analysis-based procedures for realignment of images of consecutive light micrographs of nerve tissue (cat motor cortex) have been developed. One procedure (CENT) was interactive, employing the subjective overall ‘best fit’ of two images to each other and the other (AUTOCENT) was based on an automatic comparison of two images (image thresholding and binary comparison). Images of light micrographs of several hundred consecutive sections were realigned using the interactive and the automatic methods. The interactive procedure was easy to use; realignment of an image took only a few minutes in the hands of an experienced operator and should be easy to implement on commercially available smaller computers like PCs and workstations, but the realignment was possibly disturbed by the operator's subjective expectancy of regular forms. The automatic procedure realigned 1–4 images per hour, might be implemented on smaller computers if the programming is made more efficient, was probably objective and restored the ‘true position of images’.

An optical-optical double-resonance (OODR) experiment with a Hitachi cw tunable diode laser (λ ≈ 830 nm) and a Coherent 699-29 Autoscan system (λ ≈ 570–580 nm) has been performed on gaseous BaCl. Selected B2Σ+ (v′, J′, e f ) levels were excited with the diode laser, while scanning the dye laser in the yellow spectral region. An excitation spectrum of the F2Σ+-B2Σ+ transition was recorded by detecting the undispersed UV fluorescence from the F-X deexcitation. Complementary information was collected by photographing the UV absorption spectrum of the F-X transition. A rotational analysis of the F2Σ+ state, based upon a weighted least-squares fitting of the merged OODR and UV absorption data, is presented.

A commercial low‐cost GaAlAs diode laser, operating at room temperature, was used as the tunable monochromatic light source in a high‐resolution laser spectrometer for the near‐infrared spectral region. This laser was found to have qualities fully comparable to those of the thousandfold more expensive single‐mode dye lasers commonly used in high‐resolution laser spectroscopy. Molecular spectra, obtained both in absorption and in laser‐induced emission, and optogalvanic atomic spectra clearly demonstrate the power of this extremely simple and cheap laser spectroscopic system.