Biomedical subjects

C Rath

Publications and source records attributed to C Rath.

4 recordsLinked to original sources

PubMed2001

Scaling-index method as an image processing tool in scanning-probe microscopy.

The scaling-index method (SIM) is a novel tool for image processing in scanning-probe microscopy. Originating from the theory of complex systems, the SIM can be used in order to extract structural information from arbitrary data sets. This method can readily be applied to the analysis of digital atomic-force microscopy (AFM) images. Especially for biomedical diagnostics, where genetic material is investigated by various microscopic methods, a reliable image segmentation based on the SIM algorithm is helpful. As a first application, AFM-images of GTG-banded human metaphase chromosomes (with G bands obtained by Trypsin using Giemsa) are compared with micrographs from conventional light microscopy by means of a scaling-index analysis. While the grey-level distributions of the optical and the AFM-images are largely different from each other, the scaling-index images are remarkably similar. Using this method, a fingerprint of an image can be produced which helps in the classification and interpretation of the measured data.

Algorithms↗

PubMed1997

Microstructural and Magnetic Studies on Hydrothermally Prepared Hematite

Hematite particles of various shapes and sizes have been prepared hydrothermally at different pH values ranging from 3 to 10 from ferric chloride solution at 180°C. Particle size decreases with an increase in the pH of precipitation as observed from Transmission Electron Micrographs (TEM). A comparison of TEM and mean crystallite diameter (MCD) from XRD data reveals that the particles prepared are polycrystalline in nature. The polycrystallinity decreases with an increase in the pH of precipitation, and at pH 10 almost single crystalline nature of particles is obtained. Polycrystalline monodispersed pseudocubic particles obtained at pH 3 exhibit very high coercive force and remanent magnetization which decreases with an increase in pH, whereas Morin transition temperature, Tm, shows an opposite trend. Magnetic a.c. susceptibility increases with an increase in pH up to pH 7 and then decreases. A probable mechanism for the formation of polycrystalline particles has been suggested in order to explain the above trends in magnetic behavior.

Journal Article↗

PubMed1995

Characterization of resistance to essential oils in a strain of Pseudomonas aeruginosa (VR-6).

VR-6, a strain of Pseudomonas aeruginosa, harboured a plasmid and was not inhibited by 20 microliters ml-1 of essential oils (eucalyptus, lemongrass, palmarosa, and peppermint). On treatment with acridine orange, a clone VR-6-AO-1 was obtained which was susceptible to 16.6 microliters ml-1 of eucalyptus or palmarosa oil. The plasmid DNA content of this clone was similar to the parent strain.

Acridine Orange↗

PubMed1978

Hb Potomac (101 Glu replaced by Asp): speculations on placental oxygen transport in carriers of high-affinity hemoglobins.

Blood from a woman with unexplained erythrocytosis had increased oxygen affinity, but no abnormality could be detected by electrophoresis or chromatography of her hemolysate. Separation of the tryptic peptides of her beta chains disclosed two half-sized peaks in the regions of beta T-11. The faster of these was abnormal, with the structure beta 101 Glu replaced by Asp. The new hemoglobin was called "Potomac." Three of the proband's four surviving siblings and both of her children were carriers. Differences in the ratio of carrier: normal children born to male of female carriers of 23 other high-affinity hemoglobins were not significant. The high proportion of carriers in this kindred was probably due to chance alone, and not because high maternal oxygen affinity interfered with oxygen transport to fetuses with normal hemoglobin.

Adult↗