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  • Inferior olive  (3)
  • 65R20  (2)
  • Lens culinaris  (2)
  • 1
    Digitale Medien
    Digitale Medien
    Amsterdam : Elsevier
    Plant Science 52 (1987), S. 223-227 
    ISSN: 0168-9452
    Schlagwort(e): Lens culinaris ; legume ; plant regeneration ; somatic embryogenesis
    Quelle: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Thema: Biologie
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 2
    Digitale Medien
    Digitale Medien
    Springer
    Numerische Mathematik 61 (1992), S. 311-334 
    ISSN: 0945-3245
    Schlagwort(e): 65R20
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Mathematik
    Notizen: Summary In this paper new multilevel algorithms are proposed for the numerical solution of first kind operator equations. Convergence estimates are established for multilevel algorithms applied to Tikhonov type regularization methods. Our theory relates the convergence rate of these algorithms to the minimal eigenvalue of the discrete version of the operator and the regularization parameter. The algorithms and analysis are presented in an abstract setting that can be applied to first kind integral equations.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 3
    Digitale Medien
    Digitale Medien
    Springer
    Experimental brain research 22 (1975), S. 13-24 
    ISSN: 1432-1106
    Schlagwort(e): Inferior olive ; Spinal afferents ; Ultrastructure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary Identification of the direct spinal areas (portions of the dorsal and medial accessory nuclei) within the opossum inferior olivary complex was accomplished by mapping the location of the terminal degeneration by the Fink-Heimer technique subsequent to cervical cord lesions. Following similar lesions, sampling of these same regions for electron microscopic study was assured by examination of transversely oriented, 1 μ plastic sections prior to thin sectioning. The first evidence of electron dense axon terminals was found at a survival time of 24 hours. At survival times of 36, 48 and 72 hours, degenerating presynaptic profiles shrink, become irregular in shape and are totally or partially surrounded by glial processes. Spinal terminals average 1–2 μ in their greatest dimension, contain round, clear synaptic vesicles and generally contact small diameter (0.4–1.8 μ) dendritic shafts or occasional spiny appendages. The spiny dendritic appendages make up the central core of the olivary glomeruli and these juxtaposed dendritic processes exhibit gap junctions. At longer survival times (5, 7 and 9 days) many presynaptic profiles with either round or pleomorphic synaptic vesicles remain normal in appearance and contact dendritic shafts or the spiny appendages within glomeruli. Afferents from other sources (possibly including intrinsic neurons) must terminate within the direct spinal portion of the nuclear complex to account for the numerous axon terminals which retain normal morphology after such long survival times.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 4
    Digitale Medien
    Digitale Medien
    Springer
    Experimental brain research 24 (1976), S. 219-236 
    ISSN: 1432-1106
    Schlagwort(e): Inferior olive ; Cerebellum ; Opossum
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary Although degeneration techniques suggest that cerebello-olivary fibers are limited in their origin and distribution, horseradish peroxidase and autoradiographic experiments make it clear that they arise within all cerebellar nuclei and project to most, if not all, areas of the contralateral inferior olive. Autoradiographic preparations show that cerebello-olivary fibers are highly ordered and suggest that the dentate nucleus projects primarily to the principal olive, the interpositus anterior relays particularly heavy to the dorsal accessory nucleus and the interpositus posterior distributes extensively to the medial accessory complex. Evidence for a small projection from the fastigial nucleus to the caudal medial accessory nucleus is also available. However, it appears clear that neither the dentate nor the interpositus nuclei project to just one subdivision of the olive. For example, although dentate fibers end extensively within the principal nucleus some of them also distribute to portions of the medial accessory nucleus and perhaps the dorsal accessory nucleus as well. The medial accessory olive is particularly complex and at rostral levels receives input from both interposed and dentate nuclei, whereas more caudally it receives a projection from the fastigial nucleus. Olivary fibers from both the interposed and dentate nuclei traverse the brachium conjunctivum descendons and distribute primarily to the rostral 2/3 to 3/4 of the olive, whereas those from fastigial neurons take a different route and end more caudally. Experiments utilizing horseradish peroxidase as a retrograde tracer suggest that cerebello-olivary fibers from both the interpositus anterior and dentate nuclei take origin from a population of generally small neurons.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 5
    Digitale Medien
    Digitale Medien
    Springer
    Experimental brain research 26 (1976), S. 159-170 
    ISSN: 1432-1106
    Schlagwort(e): Inferior olive ; Cerebellum ; Deep cerebellar nuclei ; Ultra-structure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary Section of the superior cerebellar peduncle just rostral to the deep cerebellar nuclei results in degenerating axon terminals within the contralateral inferior olive. The nuclear origin of this fiber system and its distribution within the subdivisions of the inferior olive were described in a companion study (Martin et al., 1976). Precise localization of these degenerating terminals within the nucleus was accomplished by the examination of 1 μ plastic sections cut from each tissue block prior to thin sectioning. Degenerating axon terminals are present in all the nuclear subdivisions and when seen with the electron microscope they frequently are localized in the previously described synaptic clusters (King, 1976). These terminals demonstrate an electron dense reaction at survival times of 2 and 3 days. By day 4, they are shrunken and irregular in shape, and typically are surrounded by astrocyte processes. Cerebello-olivary axon terminals measure 1–3 μ, contain spherical, clear synaptic vesicles and typically contact spiny appendages within the synaptic clusters (glomeruli). Thus, we have demonstrated that one of the primary axon systems which terminates within the synaptic clusters is from the cerebellar nuclei. We have yet to determine the origins of the remaining terminals within the synaptic clusters which include endings with either smaller spherical, pleomorphic or numerous dense core vesicles.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 6
    Digitale Medien
    Digitale Medien
    Springer
    Plant cell, tissue and organ culture 20 (1990), S. 75-79 
    ISSN: 1573-5044
    Schlagwort(e): Lens culinaris ; protoplasts ; osmoticum ; agarose ; callus formation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Protoplasts of Lens culinaris Medik. cv. Eston were isolated from epicotyl tissues of seedlings grown on Murashige & Skoog basal medium. For isolating the protoplasts, epicotyl tissues were digested for 12–14 h at 25°C in an isolation mixture (pH 5.7) containing 1% Cellulase RS, 0.5% Driselase, 0.25% Pectolyase Y23, 0.2M calcium chloride, 10 mM mannitol and 10 mM MES. Protoplasts were purified by flotation over 20% sucrose and washed with 0.2 M calcium chloride solution supplemented with 10 mM mannitol. Purified protoplasts were cultured at a density of 105 ml-1 in agarose (Seaplaque, 0.6%) blocks which were suspended in an identical but liquid KM8P culture medium lacking amino acids, ammonium nitrate, and coconut water but containing 0.35 M glucose and a growth regulator complement of either 2.2 μM 2,4-dichlorophenoxyacetic acid (2,4-D), 2.7 μM naphthaleneacetic acid (NAA), 2.3 μM N-(2-furanylmethyl)-1H-purine-6-amine (kinetin), 2.2 μM benzylamino purine (BAP), 2.3 μM 2-methyl-4-(1H-purine-6-ylamino)-2-buten-1-ol (zeatin), and 1.4 μM gibberellic acid (GA3), or 5.4 μM NAA and 2.2 μM each of 2,4-D and BAP. The osmotic potential of the liquid culture medium was gradually reduced over a period of 3 weeks by replacing the spent medium with a fresh medium containing 0.25, 0.1 and 0 M glucose at weekly intervals. About 6% of the dividing protoplasts developed into cell colonies after 3 weeks of culture at 25°C in diffuse light (10 μE m-2s-1). In 35–42 days the microcolonies were about 1 mm in diameter and developed into calli on transfer to agar-solidified B5 medium supplemented with growth regulators used in the protoplast culture medium and 5 mM glutamine. Attempts to regenerate plants from protoplast-derived calli have so far been unsuccessful.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 7
    Digitale Medien
    Digitale Medien
    Springer
    Computing 40 (1988), S. 91-109 
    ISSN: 1436-5057
    Schlagwort(e): 65R20 ; 45L10 ; Integral equations ; Tikhonov regularization ; parameter selection method
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Informatik
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung In dieser Arbeit betrachten wir eine besondere Variante endlich-dimensionaler Tikhonov-Regularisierung schlechtgestellter Operatorgleichungen. Konvergenzraten werden nachgewiesen und eine a-posteriori Parameterwahl wird hergeleitet, die optimale Konvergenzraten bezüglich des Datenfehlers und der endlich-dimensionalen Approximation liefert, ohne Information über die exakte Lösung zu benötigen. Schließlich präsentieren wir auch einige numerische Beispiele, bei denen lineare Splinefunktionen verwendet werden, die die theoretischen Ergebnisse bestätigen.
    Notizen: Abstract In this paper we consider a particular variant of finite-dimensional Tikhonov regularization for ill-posed operator equations. Convergence rates are established and an a-posteriori parameter choice method is derived that leads to optimal convergence rates with respect to data errors and with respect to the finite-dimensional subspace, without using any information about the exact solution. Finally, using linear splines we present several numerical examples that confirm the theoretical results.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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