Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 1975-1979  (2)
  • 1978  (2)
  • AMS(MOS): 65F10  (1)
  • Cell & Developmental Biology  (1)
Material
Years
  • 1975-1979  (2)
Year
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Numerische Mathematik 31 (1978), S. 183-208 
    ISSN: 0945-3245
    Keywords: AMS(MOS): 65F10 ; CR: 5.14
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Summary An iteration based upon the Tchebychev polynomials in the complex plane can be used to solve large sparse nonsymmetric linear systems whose eigenvalues lie in the right half plane. The iteration depends upon two parameters which can be chosen from knowledge of the convex hull of the spectrum of the linear operator. This paper deals with a procedure based upon the power method for dynamically estimating the convex hull of the spectrum. The stability of the procedure is discussed in terms of the field of values of the operator. Results show the adaptive procedure to be an effective method of determining parameters. The Tchebychev iteration compares favorably with several competing iterative methods.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 192 (1978), S. 337-350 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: This light microscopic study of the cardiac junctional tissues was based on 27 human embryos, fetuses and postnatal hearts. Evidence was presented that superficial and deep portions of the postnatal AV node were derived from two cellular primordia in the posterior wall of the common atrium at the 6-mm stage. The small right primordia was associated with the right venous valve and gave rise to the loosely organized superficial AV node that extended posteriorly to the coronary sinus ostium. A larger left primordia formed the more compact deep subdivision of the AV node located against the anulus fibrosus. In most postnatal hearts the two subdivisions are partially or completely fused to form the adult AV node. Failure of the nodal primordia to fuse during cardiogenesis may result in two separate nodal cell aggregates above the anulus. The present observations provide a rational explanation for the two AV nodal masses described in the literature and an additional specimen that is illustrated in this communication.An AV bundle was first identified in a 13-mm embryo and appeared to be derived from large clear cells of the posterior AV canal. At 25 mm the bundle formed a broad band across the top of the IV septum and continued into both ventricles. At this stage multiple cell strands penetrated the endocardial cushion to connect the AV bundle to the two nodal primordia. Failure of normal fusion between the AV node primordia and AV bundle can result in a variety of junctional anomalies including congenital heart block.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...