Comparison of magnetic flux density meter responses over a databaseof residential measurements

Fourteen possible types of magnetic flux density meters based on the Faraday induction principle have been mathematically simulated. The different readings obtained from each type when the magnetic flux density is more complex than the ideal case of a single frequency (60 Hz) with linear polarization are shown. Using a real database of residential flux densities from 17 homes, it is shown that the presence of harmonics and elliptical polarization can result in significant deviations in readings between meter types. The highest variations from the total RMS (root mean square) flux density are found with broadband meters that have derivative responses or corrected peak detectors     

The Escherichia coli hemolysin secretion apparatus--a versatile antigen delivery system in attenuated Salmonella

The E. coli hemolysin (HlyA) secretion apparatus represents a type I secretion system that is fully functional in Salmonella. The system which consists of the two specific membrane proteins HlyB and HlyD and the outer membrane protein TolC, recognizes on HlyA a C-terminally located signal sequence of about 60 amino acids. Fusion proteins to which this signal sequence is covalently linked at the C-terminus are also recognized by this secretion apparatus. The efficiency of secretion is dependent on the rate of folding of the reporter protein. Secretion-competent regions of a given reporter protein that is not secretable as entire protein can be screened by a recently constructed transposon TnhlyAs which allows the insertion of the secretion signal into any region of the reporter protein. The genetic information for antigens of any source ranging in size between 10 and 1000 amino acids can be easily inserted into a recently constructed secretion vector which will allow the secretion of the fused antigen(s) in attenuated Salmonella typhimurium strains and in other attenuated Enterobacteriaceae. By manipulation of the Hly secretion system the antigen can be either completely secreted into the environment, fixed on the outer membrane or arrested in the cytoplasm of the used carrier strain. By the use of appropriate attenuated Salmonella strains the antigen is delivered in isolated compartments or to the cytosolic compartment. The extracellular delivery of such antigens is also possible with the help of appropriate carrier strains. The immunological consequences of the different display of the processed antigen will be discussed in the paper by Hess et al in this volume. With a similar antigen delivery system the easy identification and molecular characterization of unknown antigens recognized by the immune system in an infection is also feasible.     

Evaluation criteria in follow-up studies of flexor tendon therapy

Oxphenisatin is known to induce liver damage and is suspected to cause or perpetuate chronic liver disease. In order to evaluate the hepatotoxic effect of long-term therapy with oxyphenisatin 26 consecutive patients with rheumatoid arthritis were investigated for the presence of liver disease. In all cases, liver biopsy, biochemical liver function tests and determination of Hepatitis-B antigen were performed. Ten patients showed no pathological changes in the liver biopsy and a further 2 had only non-specific changes. Seven patients had fatty liver, 5 passive congestion, one haemosiderosis and only one had cirrhosis of the liver. No correlation was found between the activity of rheumatoid arthritis, and duration of the disease, the drug therapy given, and the liver damage.     

Die einzelnen Lebensmittel (Chemie, Technologie, Anolytik)

Ohne Zusammenfassung     

Berechnung des Kriechverhaltens druckbeanspruchter dickwandiger Kugelbehälter aus anisotropem Material

Zusammenfassung Das station?re Kriechverhalten von dickwandigen, mit innerem überdruck beaufschlagten kugelf?rmigen Beh?ltern wird unter Berücksichtigung der „tensoriellen Nichtlinearit?t” der Materialgleichungen untersucht. Unter Verwendung der Theorie endlicher Verzerrungen werden die Untersuchungen für isotrope wie auch für anisotrope, inkompressible Werkstoffe durchgeführt. Es wird dabei die Annahme getroffen, da? mittels einer Regelung der innere Druck w?hrend des Kriechvorgangs konstant gehalten wird. Die Untersuchung wurde von der Deutschen Forschungsgemeinschaft (DFG) finanziell unterstützt, wofür an dieser Stelle gedankt sei.     

Precision X-ray spectroscopy on 8.5 MeVamu heavy ions

A new experimental capability has been developed at the Lawrence Berkeley Laboratory Super-HILAC to investigate questions relating to high resolution atomic spectroscopy. A key element of these measurements is a dual arm Johann spectrometer. The ion beam passes inside the Rowland circle of two curved crystals which are mounted such that diffracted X-rays have equal and opposite linear Doppler shifts. The X-ray lines are detected with high speed X-ray film mounted on the Rowland circle. The beam-crystal geometry is arranged so a spectral range θ_B ~ 30°–70° is detected. The spectrometer efficiency is high with useful exposures obtained with only 10 mC of beam. A wavelength calibration is obtained by simultaneously exposing the film with diffracted K and L X-rays from an X-ray tube. X-ray lines from the beam are slanted, with respect to the calibration lines, due to Doppler shifts arising from X-rays incident on the crystal at angles other than perpendicular to the diffraction plane. The slope of these lines provides an independent determination of the beam velocity, which is used to correct for the transverse Doppler shift. Typical results are presented.     

MLT and MT student performance on a preliminary psychomotor test battery

Psychomotor ability is a neglected component of student clinical evaluation in the laboratory setting. This paper describes development of an experimental psychomotor test battery containing mechanical comprehension, spatial perception, and manual dexterity subscales. A small sample of MLT and MT students constituted the study population used to determine interrelationships among the subscales. Pearson product moment correlations and factor analysis suggest isolation of hand-eye motor and perception-intelligence psychomotor components in the battery. Clinical laboratory implications of the findings are discussed.     

On the efficient and accurate solution of the skew-symmetric eigenvalue problem: An arrangement of new and already known algorithmic formulations

Algorithms are presented to solve the special eigenvalue problem $\text{AZ}\text{=}\text{Zλ}$, where $\text{A}$ is skew-symmetric. The effective use of Householder's method, the bisection method and inverse iteration for solving the complete eigen-value problem are described in some detail. Simultaneous vector iteration is formulated for skew-symmetric matrices. The amount of work for the skew-symmetric Jacobi algorithm and the simultaneous vector iteration may be reduced by using the solution of a simplified eigenvalue problem. For Hermitian matrices also quadratic eigenvalue bounds for groups of eigenvalues and linear bounds for groups of eigenvectors are derived. The case where the set of calculated eigenvectors is not orthonormal is considered in some detail. In principle, the skew-symmetric eigenvalue problem may be easily transformed into a symmetric eigenvalue problem; but such a procedure has the following disadvantages: first, the results are in general less accurate, and, second, the eigenvectors which belong to well separated eigenvalues are not uniquely determined.