The ®alidity of an online state estimator for a semi-batch MMArMA solution copolymerization reactor was established using online densitometer and ®iscometer. Using the ( ) con®entional extended Kalman filter EKF as the state estimator, the experiment was conducted under both isothermal and nonisothermal conditions for application to the control of copolymer properties. Further analysis was made...

The bone mineral density (BMD) and the bone mineral content (BMC) in the bone tissue of the bilateral first phalanges of horses' thoracic limbs were analysed. The research material consisted of isolated pastern bones derived from 22 horses. The research was conducted with the use of a Norland model Excell Plus densitometer (Fort Atkinson WI, USA), using affinited beam X-ray technology and an an...

Pulse oximetry is based on a relatively new concept, using the pulsatile variations in optical density of tissues in the red and infrared wavelengths to compute arterial oxygen saturation without need for calibration. The method was invented in 1972 by Takuo Aoyagi, a bioengineer, while he was working on an ear densitometer for recording dye dilution curves. Susumu Nakajima, a surgeon, and his ...

Spices play an important role in the chemoprevention and they can be a rich source of biologically active compounds such as triterpenes in the human diet. A method based on high performance thin-layer chromatography combined with densitometry for determination of ursolic and oleanolic acids in some common spices was elaborated. The prechromatographic derivatization with 1% of iodine solution wa...

Vertebral fractures are highly prevalent in the elderly population, and epidemiologic studies have found that these fractures are associated with an increased risk of future spine or hip fractures independent of bone mineral density. Only 20%-30% of vertebral fractures are recognized clinically; the rest are discovered incidentally on lateral spine radiographs. Lateral spine x-rays have not bee...

Aflatoxin concentrations in agar media were estimated with a direct technique that quantifies the fluorescence of agar containing aflatoxins. Tubes containing 5 ml of an agar medium inoculated with spores of aflatoxin-producing Aspergillus isolates were incubated for 3 days at 30 degrees C and set in a carriage specifically designed to carry culture tubes in a scanning densitometer. Fluorescenc...

One of the known drawbacks of in vitro dermal absorption methods is their high interlaboratory variation. Although often attributed to biological skin differences, it has been shown that validation of other parameters such as temperature and stirring speed can reduce the high variability observed. The Organisation for Economic Co-operation and Development (OECD) and, at the EU level, the Scient...

A rapid and reproducible method for the electrophoretic separation and quantitation of serum alkaline phosphatase isoenzymes is described. Sera from patients with biopsy proven parenchymal liver diseases and diseases related to increased osteoblastic activity were subjected to electrophoresis using a continuous tris-borate buffer on a five percent polyacrylamide gel. Following electrophoresis, ...

OBJECTIVE To determine the age of peak bone mass (PBM) in Mexican women and factors associated with both BMDa and corrected BMD (BMDcorr) at the femoral neck and the spine (L2-L4). MATERIAL AND METHODS Data on 461 women between 9 and 24 years old was used. An interview was performed and height and weight were measured. BMDa was measured by a densitometer and BMDcorr by the method proposed by ...

Soy (Glycine max L., Fabaceae) and soy products are becoming more popular because of their low toxicity and therapeutic effects. Soy possesses antioxidant, anti-inflammatory and anti-allergic properties, however, the most important is its estrogenic activity associated with occurrence of phytoestrogens. Isoflavones with phytoestrogenic effects were determined in four commercially available soya...