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Showing papers by "University of Jena published in 1978"



Journal ArticleDOI
TL;DR: In this article, the equilibrium geometry and spectroscopic properties of biphenyl in the S0 and S1 states were determined by minimization of the total energy with respect to all cartesian coordinates.
Abstract: Equilibrium geometry and spectroscopic properties of biphenyl in the S0 and S1 state Equilibrium geometries for the S0 and S1 state of biphenyl were determined by minimization of the total energy with respect to all cartesian coordinates. The molecule is twisted in the S0 state (20°), but becomes planar in the S1 state. Using these results, an interpretation of the fluorescence and absorption spectra can be given. In passing from the S0 to the S1 state equilibrium geometry a remarkable change of the state ordering occurs.

43 citations


Journal ArticleDOI
Hans Stephani1
TL;DR: In this article, the connection between symmetric and skew-symmetric Killing tensors is studied, and it is shown that in all type-D vacuum metrics admitting a symmetric killing tensor, this Killing tensor can be given in terms of a skew symmetric tensor.
Abstract: The connection between symmetric and skew-symmetric Killing tensors is studied. Some theorems on skew-symmetric Killing tensors are generalized, and it is shown that in all type-D vacuum metrics admitting a symmetric Killing tensor, this Killing tensor can be given in terms of a skew-symmetric Killing tensor.

37 citations


Journal ArticleDOI
TL;DR: In this paper, a detailed survey of CH bond lengths in the S 0 and S 1 states of 1, 1′-binaphthyl has been given, and an interpretation of the fluorescence S 1 → S 0, and absorption spectra S m ← S 0 in rigid and fluid solutions is given.

32 citations


Journal ArticleDOI
TL;DR: In this article, the photochromism of 2-(2′,4′-dinitrobenzyl)-pyridine was investigated by means of laser flash photolysis and two coloured transients were observed in the spectral ranges of 390-410 nm and 510-580 nm in both polar and nonpolar solvents.

30 citations


Journal ArticleDOI
TL;DR: The cytology of 6 osteosarcomas was examined by electron microscopy, and a multipotent mesenchymal cell rather than an osteoblastic cell is assumed to be the ancestor cell.
Abstract: The cytology of 6 osteosarcomas was examined by electron microscopy. In keeping with the varied pattern of osteosarcomas seen by light microscopy several types of tumor cells could be differentiated: osteoblast-like, fibroblast-like, chondroblast-like, osteoclast-like and histiocyte-like cells. Moreover, atypical malignant mesenchymal cells and vascular spaces were present. The individual cytoplasmic organelles are not considered to be specific to particular types of cell as seen from the discussion of the significance of rough endoplasmic reticulum, microfilaments and lysosomes. Only examination of the composite pattern of subcellular organelles allows the differentiation of certain cell types. All tumor cells visible in osteosarcomas are considered as modifications of a transformed common progenitor cell. Because of the variegated cytological picture a multipotent mesenchymal cell rather than an osteoblastic cell is assumed to be the ancestor cell.

29 citations


Journal ArticleDOI

29 citations


Journal ArticleDOI
TL;DR: The frontal ganglion of the cockroach Periplaneta americana was studied histologically and its neuronal pathways were mapped by use of axonal cobalt iontophoresis.
Abstract: The frontal ganglion of the cockroach Periplaneta americana was studied histologically and its neuronal pathways were mapped by use of axonal cobalt iontophoresis. Neurons and fiber tracts of the frontal ganglion are directly linked with different regions of the central nervous system (tritocerebrum, protocerebrum, subesophageal ganglion) and with the more caudal parts of the stomatogastric nervous system (hypocerebral ganglion, nervus oesophagei).

28 citations


Journal ArticleDOI
R. Kowarschik1
TL;DR: In this article, the amplitudes of the first-order diffracted waves and the diffraction efficiency are calculated for sequentially superposed phase gratings stored in dielectric reflection holograms.
Abstract: On the basis of the theory of coupled waves the amplitudes of the first-order diffracted waves and the diffraction efficiency is calculated for sequentially superposed phase gratings stored in dielectric reflection holograms. The investigations are restricted to the case of a fixed reference wave during recording and Bragg-angle incidence. By analogy to the transmission volume grating the coupling effects which appear between incident beams and diffracted waves give the possibility of building up beam-couplers and -splitters with certain coupling parameters determined by the recording process. Moreover, reflection gratings allow a favourable combination between coupling and reflecting properties and avoid the diffraction efficiency oscillations that are characteristic of transmission gratings. The performance of the reconstruction process with several waves simultaneously allows the tuning of the intensities of diffracted waves with dependence on amplitude or phase differences between incident beams.

26 citations


Journal ArticleDOI
TL;DR: The crystal and molecular structure of tetramesitylvanadium has been determined by three-dimensional X-ray analysis as mentioned in this paper, and the experimental density of 1.15 g cm−3 is in agreement with the calculated one with four molecules per unit cell.

26 citations


Journal ArticleDOI
TL;DR: In this paper, the size and shape dependence of some properties of finite f.c.z. clusters are investigated using the tight binding approximation, and results for the s-like band structure, binding energy per atom, and Fermi level are presented in dependence on the number of atoms.
Abstract: The size and shape dependence of some properties of finite f.c.c. clusters is investigated using the tight binding approximation. Three different sequences of rectangular prismatic f.c.c. crystallites with (100) surfaces (edge length A, B, C) are taken into account, namely cubes (A = B = C), plates (A = B ≫C) and rods (A = B≪ C). Numerical results for the s-like band structure, binding energy per atom, and Fermi level are presented in dependence on the number of atoms, up to some millions of atoms. The results visualize the convergence of the cluster properties and indicate their shape specifity. Im Rahmen der Tight-Binding-Naherung wird die Grosen- und Habitus-Abhangigkeit einiger Eigenschaften endlicher k.f.z.-Cluster untersucht. Drei verschiedene Folgen von rechteckigprismatischen k.f.z.-Kristalliten mit (100)-Oberflachen (Kantenlange A, B, C) werden betrachtet, namlich Wurfel (A = B = C), Platten (A = B ≫C) und Stangen (A = B≪ C). Numerische Resultate fur die Bandstruktur, die Bindungsenergie pro Atom und das Fermi-Niveau in Abhangigkeit von der Anzahl der Clusteratome werden vorgestellt. Die grosten Cluster enthalten einige Millionen Atome. Die Resultate veranschaulichen das Konvergenzverhalten der Clustereigen-schaften und weisen auf deren Gestaltabhangigkeit hin.


Journal ArticleDOI
TL;DR: In this paper, the action of N-bromosuccinimide and water on (Z, Z)-1,5-cyclooctadiene (1) results in the formation of the following cyclo-cycles:
Abstract: The action of N-bromosuccinimide (NBS) and water on (Z, Z)-1,5-cyclooctadiene (1) results in the formation ofendo,endo-2,5-dibromo-9-oxabicyclo [4.2.1]nonane (2),endo,endo-2,6-dibromo-9-oxabicyclo[3.3.1]nonane (3),trans-6-bromo-(Z)-cycloocten-5-ol (4a),endo-6-bromo-cis-bicyclo[3.3.0]octan-2-ol (5a), andtrans-5,6-dibromo-(Z)-cyclooctene (6).2 and3 are considered to be produced from intermediary4a via transanular participation of the hydroxyl group.5a is formed in a result of transanular double bond participation.

Journal ArticleDOI
Eduard Herlt1
TL;DR: In this paper, a new class of axially symmetric static electrovacuum solutions and the Kerr solution are obtained from the van Stockum metric, which contains an infinite set of asymptotically flat solutions (in closed form), each of which involves an arbitrary set of parameters.
Abstract: This paper shows that a new class of axially symmetric static electrovacuum solutions and the Kerr solution are obtainable from the van Stockum metric. The new class contains an infinite set of asymptotically flat solutions (in closed form), each of which involves an arbitrary set of parameters. The parameters have to be interpreted as functions of massm, chargee, and higher electric multipole momentsα i of the particle. The casee=α i =0 leads to the Darmois metric. Well-known and new examples are given.

Journal ArticleDOI
TL;DR: In this paper, the Avrami equation, the 2-dimensional diffusion equation and the first-order kinetics were calculated as theoretical values, both for the total reaction and for individual reaction intervals.

Journal ArticleDOI
TL;DR: By means of this procedure matrix complexes of hyalin cartilage were stained such as to display granular subunits about 25 to 35 A in diameter as the demonstration of proteoglycan constituents of chondromucin aggregates.

Journal ArticleDOI
TL;DR: In this paper, the photochromism of 2,2′,4,4′-tetranitrodiphenylmethanes was investigated by means of laser flash photolysis.

Journal ArticleDOI
O. Bílek1, P. Kadura1
TL;DR: In this paper, the size and habit dependence of one-electron states of small crystallites in the Huckel approximation were investigated, and analytic formulae for s-quasi-bana electronic levels of finite s.c.c and f.f.c with (100) surfaces were presented.
Abstract: The properties of small crystallities more or less deviate from those of infinite periodic crystals. An investigation is made of the size and habit dependence of one-electron states of small crystallites in the Huckel approximation. Analytic formulae for s-quasi-bana electronic levels of finite s.c. and f.c.c. crystallites with (100) surfaces are presented. The symmtery classification of the levels for the f.c.c. crystallites possessing C4v point symmetry is also given. Die Eigenschaften kleiner Kristallite unterscheiden sich in bestimmter Weise von denen unendlich periodischer Kristalle. Es wird ein Beitrag zur Untersuchung der Grosen- und Habitus-Abhangigkeit der genaherten Einelektronenzustande kleiner Kristallite durch Angabe einer geschlossenen Formel fur die Niveaus der s-Quasibander endlicher einfach kubischer und k.f.z.-Kristallite mit (100)-Oberflachen in Huckel-Naherung geliefert. Im Spezialfall der C4v-Symmetrie der k.f.z.-Kristallite wird die Symmetrieklassifizierung der Niveaus angeben.

Journal ArticleDOI
TL;DR: In this paper, the spectral properties of 2,2′bipyridinnickel (0) complexes with heteroolefins and polar olefs (L) were investigated.

Journal ArticleDOI
TL;DR: Immunoelectrophoresis of extracts from frontal ganglia with polyspecific anti-neurosecretion-serum reveals a single precipitation line, indicating that the immunocytochemical localization of neurosecretory material is due to reaction with a specific as well as a crossreagent antibody.
Abstract: The frontal ganglion, part of the stomatogastric nervous system, contains about 60 to 80 neurons, 25 to 30 micron in diameter. A well developed Golgi system, producing dense-core vesicles, lysosomes, multivesicular bodies and dense bodies are abundant. Glia elements are sparsely distributed. Many nerve fibres contain granules of different size and electron density. Five groups of fibres can be distinguished: Fibres with granules of about 200 nm (type A), fibres with granules of about 160 to 170 nm (type B), fibres with granules of about 80 to 100 nm (type C) and those with synaptic vesicles of 50 nm (type D) respectively. A fifth very small type contains neither vesicles nor granules. Special attention was paid to synaptic contacts. The divergent dyad seems to be the main type in the frontal ganglion. Frequently, neurosecretory endings are observed in presynaptic position. Immunocytochemical "staining" of neurosecretory material closely corresponds to the distribution of type A fibres, as observed electron microscopically. Immunoelectrophoresis of extracts from frontal ganglia with polyspecific anti-neurosecretion-serum reveals a single precipitation line, indicating that the immunocytochemical localization of neurosecretory material is due to reaction with a specific as well as a cross-reagent anitbody.

Journal ArticleDOI
TL;DR: Using two different lectins which were conjugated with TRITC or FITC, respectively, a double labeling of different lectin-binding sites in tissue sections was achieved and resulted in a specific and brilliant fluorescence in tissue staining.
Abstract: Methodical investigations on the coupling of lectins (Con A, LcL, WGA, RcA) to tetramethylrhodamine isothiocyanate (TRITC) are reported. 20 μg of TRITC per mg of lectin were found to be the optimal amount of TRITC for the conjugation. With this fluorochrome: protein ratio conjugates were produced which resulted in a specific and brilliant fluorescence in tissue staining. The optimally conjugated lectins were separated on DEAE-Sephadex-A 50. Using two different lectins which were conjugated with TRITC or FITC, respectively, a double labeling of different lectin-binding sites in tissue sections was achieved.

Journal ArticleDOI
Jürgen Roth1
TL;DR: In this paper, the internalization of plasma membrane components labelled with ConA and peroxidase was investigated in monolayer cultures of rat liver cells, and the results indicated that the membrane internalization and the membrane recycling simultaneously effect an enhancement of membrane biogenesis and exocytosis, thus compensating for the membrane removal by internalization.

Journal ArticleDOI
Hans Triebel1
TL;DR: In this article, relations between BESOV spaces B8∞,q, HOLDER spaces C8, ZYGMUND spaces ˆ8, dual spaces of the spaces F81,q and the space of bounded mean oscillation BMO, the space L∞.
Abstract: The paper deals with relations between the following types of spaces: of BESOV spaces B8∞,q, HOLDER spaces C8, ZYGMUND spaces ˆ8, dual spaces of the spaces F81,q, the space of bounded mean oscillation BMO, the space L∞. The following properties are considered: Inclusions, interpolation, duality, multipliers, and equivalent norms.

Journal ArticleDOI
TL;DR: In this paper, Rabbits were exposed repeatedly to formalin irritation using a new oral tank which allows a chronical contact with the oral mucosa, and a preneoplastic, unrest of the epithelium with dyskeratosis could be produced.

Journal ArticleDOI
TL;DR: After repeated administrations of various organic anionic drugs to rats of different ages, an enhancement of p-aminohippurate accumulation was observed in renal cortical slices from adult but not from newborn and infant rats, which can be interpreted as specific substrate-induced stimulation of the organic anion transport.
Abstract: After repeated administrations of various organic anionic drugs to rats of different ages, an enhancement of p-aminohippurate accumulation was observed in renal cortical slices from adult but not from newborn and infant rats. The effect can be interpreted as specific substrate-induced stimulation of the organic anion transport.

Journal ArticleDOI
TL;DR: This study deals with the spontaneous activities of the frontal ganglion of the cockroach, Periplaneta americana, where newly moulted animals show volley like discharges, which are identical with the rhythm in the nervus connectivus (see below).

Journal ArticleDOI
TL;DR: It is very probable from these and other results that the short-term effect is brought about by the emergence of humoral growth stimulators which are evidenced in restorative regeneration and, therefore, accounts for the promoting activity of carcinogens.

Journal ArticleDOI
TL;DR: In this article, the Ultrastruktur des Amnions von Frauen with normalem Schwangerschaftsverlauf untersucht unter besonderer Berucksichtigung des Problems der transamniotischen Stoffpassage and the Rolle der mikrofilamentaren and mikrotubularen Strukturen.
Abstract: Es wurde die Ultrastruktur des Amnions von Frauen mit normalem Schwangerschaftsverlauf untersucht unter besonderer Berucksichtigung des Problems der transamniotischen Stoffpassage und der Rolle der mikrofilamentaren und mikrotubularen Strukturen. Das normale Amnionepithel besitzt eine Ultrastruktur, die in hohem Mase eine Furchtwasserzirkulation einschlieslich der darin gelosten Stoffe auf extrazellularem Wege gestattet. Die Grundlage hierfur bilden zahlreiche weite, stark gegliederte Interzellularkanale (IZ-Kanale), die das Amnionepithel durchdringen. Das amniotische Interzellularsystem wird nicht durch Zonulae occludentes (Schlusleisten) verschlossen. Der grosmolekulare Tracer Ferritin diffundiert frei durch die weiten IZ-Kanale und passiert auch die subepitheliale Basalmembran ohne Zeichen einer Hemmung. Alle Amnionzellen enthalten neben Mikrotubuli ein auffallend gut ausgebildetes mikrofilamentares System. Es durchzieht in Form von Filamentbundeln oder -netzen weite Zellbereiche und erstreckt sich bis in die zahlreichen Zellfortsatze. Messungen weisen darauf hin, das das Mikrofilamentsystem aus zwei verschiedenen Fasertypen besteht mit einem Durchmesser von ca. 50 bzw. 80 A. Durch Cytochalasin B-Einwirkung wird der groste Teil der Mikrofilamente abgebaut. Ihre Depolymerisierung hatte bemerkenswerterweise stets ein allgemeines Verschwinden der IZ-Kanale zur Folge sowie eine sehr deutliche Hemmung der interepithelialen Ferritinpassage. Die vorliegenden experimentellen Befunde erlauben die Schlusfolgerung, das die amniotischen Mikrofilamente eine cytoskelettare Funktion haben und offensichtlich einen druckmechanischen Verschlus der wichtigen interepithelialen Diffusionskanale verhindern. Daruber hinaus befahigen die Mikrofilamente sehr wahrscheinlich die Amnionepithelzellen zu Mikrokontraktionen, die im lateralen Corticalplasma zu Veranderungen der Weite der IZ-Kanale fuhren, wodurch die Permeabilitatseigenschaften des Amnions aktiv beeinflust werden konnen.

Journal ArticleDOI
TL;DR: In this article, the glass formation and phase separation in the systems TlGeSe and PbSeGeSe2Se were investigated applying defined melting conditions, and the compositions of the interconnected phases were determined by chemical analysis, scanning electron microscopy, and by measurements of Vickers hardness.
Abstract: Fur definierte Schmelzbedingungen wird die Glasbildung in den Systemen TlGeSe und PbSeGeSe2Se beschrieben. Bei hohen Selen- und geringen Germaniumgehalten treten in beiden Fallen ausgedehnte Gebiete mit Mikro- und Makrophasentrennung auf. Zur Festlegung des Konnodenverlaufs in den Mischungslucken werden naschemische Analysen, rasterelektronenmikroskopische Untersuchungen und Mikrohartemessungen herangezogen. Fur die Transformationstemperaturen Tg und die Mikroharten HMV homogener TlGESe-Glaser ergeben sich lineare Abhangigkeiten von den Naherungswerten ΔAH1 fur die molare Atomisierungsenthalpie der Proben. Correlations between Properties of Chalcogenide Glasses. V. Glass Formation and Phase Separation in the Systems TlGeSe und PbGeSe The glass formation in the systems TlGeSe and PbSeGeSe2Se is investigated applying defined melting conditions. In both systems exist – at high Se and low Ge contents – large regions of liquid immiscibility and microphase separation. The compositions of the interconnected phases were determined by chemical analysis, scanning electron microscopy, and by measurements of Vickers hardness. Transformation temperatures Tg and hardness numbers HMV of homogeneous TlGeSe glasses are in a linear relationship with the approximate values ΔAH1 for the atomization energies of the samples.

Journal ArticleDOI
TL;DR: Rapid loss of cochlear microphonics in guinea-pigs previously exposed to high-energy impulse noise was shown to be related to the breakdown of the endolymphatic boundary.
Abstract: Rapid loss of cochlear microphonics in guinea-pigs previously exposed to high-energy impulse noise was shown to be related to the breakdown of the endolymphatic boundary. The cochlear duct was rendered leaky by deterioration of the reticular membrane, and damage of sensory and supporting cells.