Showing papers by "University of Vienna published in 1971"

On the Gravitational field of a massless particle

Abstract: The gravitational field of a massless point particle is first calculated using the linearized field equations. The result is identical with the exact solution, obtained from the Schwarzschild metric by means of a singular Lorentz transformation. The gravitational field of the particle is nonvanishing only on a plane containing the particle and orthogonal to the direction of motion. On this plane the Riemann tensor has a δ-like singularity and is exactly of Petrov typeN.

Plasmatic resistance and rate of respiration and photosynthesis of Zostera marina at different salinities and temperatures

Abstract: Zostera marina L. was studied at the Izembek Lagoon, Alaska Peninsula. Two morphologically different forms, tidepool and subtidal, can be distinguished. Both show a high tolerance to different salinities and temperatures. The plasmatic resistance was found in a range of distilled H2O up to 3.0 seawater (24 h) and between-6° and 34°C (12 h). Within these resistance limits, the photosynthesis, which has its maximum in normal (1.0) seawater, decreases nearly to zero not only in distilled H2O but even in 2.0 seawater, and increases with the temperature in the tidepool form up to 35°C, but in the subtidal form up to 30°C only. At higher temperatures photosynthesis declines sharply in both forms. Respiration has its minimum in distilled H2O and at 0°C and increases with increasing salinity and temperature.

L1-Algebras and Segal Algebras

Abstract: Certain ideals in L1-algebras.- The property P1, applications.- Some properties equivalent to P1. Relativization.- Segal algebras.- Examples.- Approximate units in Banach algebras: definitions.- Approximate units in Banach algebras: lemmas.- Approximate units in Segal algebras.- Some general results on Segal algebras.- Certain ideals in Segal algebras.- Canonical representation of the ideals.- Segal algebras and normal subgroups.- Segal algebras on quotient groups.- Closed ideals with approximate units in Segal algebras.- Symmetric Segal algebras on compact groups.- Segal algebras on abelian groups.- L1-algebras of compact and of abelian groups.

Analysis of the human karyotype using a reassociation technique.

Abstract: A characteristic banding pattern can be made visible in human chromosomes by a denaturating and renaturating procedure performed on cytological preparations. The banding pattern is characteristic of each chromosome pair, allowing easy identification of all human chromosomes. The method is likely to provide a useful tool in the identification of mammalian chromosomes and in the study of aberrations and variations in the chromosome set.

Ultrastructural Localization of Pemphigus Autoantibodies within the Epidermis

Abstract: INDIRECT immunofluorescent techniques show that the sera of patients with pemphigus vulgaris contain immunoglobulins (IgG) which specifically bind to the presumed site of the intercellular space of stratified squamous epithelia1–3. Pretitres of these diagnostic antibodies reflect the progress of the disease as well as the patient's response to treatment4. There is considerable evidence that the IgG immunoglobulins1,5 and complement6 found in the intercellular spaces represent autoantibodies4. These data imply that the distribution of the IgG deposits corresponds to the primary lesion in this disease7,8.

Banding Pattern of Human Chromosomes

Abstract: STUDIES of mammalian chromosomes have advanced rapidly since the introduction of the quinacrine fluorescence technique1 and other procedures which are believed to locate repetitive DNA sequences in cytological chromosome preparations2,3. To improve these techniques, a method has been developed which can provide further information about chromosome organization.

Neuropathological Conditions Related to Neuroaxonal Dystrophy

Abstract: Neuroaxonal dystrophy (NAD) is an important autonomic phenomenon in physiological brain ageing as well as the pathognomonic pathological substrate of a group of degenerative processes of the CNS related to normal brain ageing. The pathogenetic analysis of the role of NAD in physiology and pathology opens a wide field of neurobiology and offers a new approach to the general concept of disease in the neurological sciences. Some of the basic problems encountered in this study concern the mechanism of axonal metabolism and transport as well as of ordinary axonal reactions and these problems could be successfully approached by experimental research oriented by those findings in naturally occurring disease.

The cenozoic rhyolite-andesite association of the chilean andes

Abstract: The eruption centres of late volcanism in Chile are situated in two separate areas in the northern and southern High Cordillera. In the north, the ignimbrites of the Rhyolite Formation and the rocks of the « Andesite » Formation occur in about equal proportions, and recent activity is meagre. In the south, the rocks of the « Andesite » Formation predominate, and many volcanoes are in a highly explosive phase of activity. Field relationships, petrological and geochemical data show that the rocks of both Formations are closely related to each other. There is evidence that the magmas of the Rhyolite Formation were formed by fusion of sialic material in the upper parts of the crust. The data for the volcanics of the « Andesite » Formation are inconsistent with their derivation by fractional crystallization of a basaltic parent or by direct mantle derivation involving a single stage process. The authors suggest that the « andesitic » magmas are products of a primary andesitic magma originated by partial fusion of material of the lower crust. Assuming that the « andesitic » magmas of the central parts of the Andes are derived from the upper mantle, this would mean — in the light of the Sr87/Sr86 data — that the upper mantle in the central region of the Andes is essentially more radiogenic than in other orogenic areas; moroever, it should be very similar in its chemical and Sr87/Sr86 composition to that of the lower crust.

In vitro analysis of the hormonal basis for the sexual dimorphism in the embryonic development of the mouse mammary gland

Abstract: Factors underlying the sexual dimorphism in the embryonic development of mouse mammary glands were analysed in vitro and the following results were obtained: 1. Mammary gland rudiments of 13-day male embryos, explanted immediately before the onset of their regression, were perfectly capable of developing into female-type glands in vitro . Even some of the glands of 14-day male embryos, where the regression process had already begun, recovered after explantation and underwent female-type morphogenesis. 2. Combined explantation of 13-day testes with mammary rudiments of female embryos of 12–14 days gestation resulted in male-type regression of the glands. 3. The addition of testosterone to the culture medium caused a similar regression of explanted (female) mammary-gland rudiments. The minimal effective concentration of the hormone was 10−9m, or 0·00029 μg/ml. 4. Cultured mammary rudiments of 15-day female embryos were no longer responsive to the presence of testis explants. They failed to undergo regression and continued their development in vitro . From these results the following conclusions were drawn: ( a ) The sexual dimorphism in the embryonic development of mouse mammary glands is caused by their suppression in males and not by their stimulation in female embryos. ( b ) The androgenic hormones in male foetuses are solely responsible for the regression of the mammary rudiments. They exert their effect directly on the gland without the need for involvement of other endocrine organs. ( c ) The genetic sex of the gland itself has no influence on its developmental capacities as: (i) glands of male embryos are able to develop in the absence of androgens, and (ii) glands of female embryos undergo typical male-type regression in vitro when exposed to the presence of foetal testes or of testosterone.

Zur Stereochemie des Te(IV) gegenüber Sauerstoff

Abstract: Die Koordination von Sauerstoff um Te(IV) zeigt in Kristallstrukturen eine Besonderheit, welche bisher nicht erkannt worden zu sein scheint: Wahrend die Konfiguration von Te(IV) mit seinen drei nachsten Nachbarn in Bindungslangen und Bindungswinkeln recht konstant ist, variiert die Lange der viertnachsten Te−O-“Bindung” stark (von 2.08 bis 2.98 A); dennoch ist ihre Richtung bemerkenswert konstant, wenn man Te−O-Abstande groser als 2.75 A vernachlassigt. Auch die Richtungen zu weiteren Sauerstoff-Nachbarn (bis 3.0 A) sind nicht statistisch verteilt, sondern gewisse raumliche Bereiche werden vermieden. Es wird versucht, diese phanomenologischen Befunde zu interpretieren.

Neuroaxonal dystrophy in man: character and natural history.

Abstract: A short correlative review is given of the light and electron microscopical features and histochemical reactions of dystrophic axons in the mature human CNS. Their ultrastruc- tural similarities to axonal changes in the disease entity of the neuroaxonal dystrophies and various experimental conditions are confirmed. The incidence of axonal spheroids in the gracile and cuneate nuclei and in the reticular zone of the substantia nigra was studied in 1450 consecutive autopsies and correlated with age and underlying disease process. Axonal dystrophy of posterior column nuclei and substantia nigra showed a significant age-dependancy without predilection for either sex. The incidence of dystrophic axons in the globus pallidus and other sites was also examined. No clear relationship of the severity and frequency of the involvement of gracile nucleus with any underlying disease was established, while axonal dystrophy in substantia nigra showed significant correlations to alcoholic encephalopathies and Parkinson’s syndrome, and a trend to negative relationship with presenile cerebral atrophies. In addition to the natural occurrence of dystrophic axons as a physiological, age-dependant phenomenon, these lesions may arise prematurely and to excess in a variety of natural and experimental disorders. The reported findings suggest that some metabolic factors are involved in the pathogenesis of dystrophic axonal changes. Relations to axonal dying-back processes are discussed.

Control of granulocyte production: separation and chemical identification of a specific inhibitor (chalone).

Abstract: . It has previously been shown by others that blood serum contains inhibitors of blood cell production acting on the proliferation of granulocy tic and erythrocytic precursor cells in the bone marrow. It is now shown that the active extract from calf blood serum can be further subfractionated into six different components, all of them exhibiting inhibitory effects on the proliferation of rat bone marrow cells in vitro. Ascitic fluid from rats treated intraperitoneally with polyvinylpyrrolidone contains inhibitors which apparently are the same as those found in calf serum. It was further possible to demonstrate that only one of these inhibitors is contained in mature granulocytes where it is actively synthesized from amino acids and subsequently released into the surrounding medium. By chromatography on Sephadex G-25 of this conditioned medium the inhibiting substance could be obtained in relatively pure form being contaminated only by low amounts of two ninyhdrin-positive substances. the experiments allow the granulocytic inhibitor to be identified as a polypeptide with a molecular weight below 5000. the results suggest that this substance is the granulocytic chalone.

Progressive supranuclear palsy (subcortical argyrophilic dystrophy).

Abstract: Two female cases of progressive supranuclear palsy (“heterogeneous system degeneration”) with histological findings are reported. Clinically, vertical gaze palsy, dystonia, akinesia, pseudobulbar palsy and mental impairment were prominent. Pathologically, widespread appearance of neurofibrillary tangles of the subcortical type in the brain stem and basal ganglia was associated with neuronal loss and gliosis in the substantia nigra, subthalamic nuclei and pallidum. There was less severe affection of the dentate nuclei and minimal cortical involvement. The distribution of changes in “subcortical argyrophilic dystrophy” is critically compared with and separated from brain stem affection in (pre)senile Alzheimer's disease.

Fluorescenzuntersuchungen über die Längenvariabilität des Y-Chromosoms beim Menschen

Abstract: Die Lange des Y-Chromosoms ist bei verschiedenen Mannern bekannterweise von wechselnder Grose. Nach Farbung mit Atebrin zeigt dieses Chromosom eine auffallig starke Fluorescenz im distalen Abschnitt des langen Arms. Es lassen sich somit 3 Abschnitte im Y-Chromosom unterscheiden: 1. der kurze Arm, 2. der unauffallig fluorescierende proximale Teil und 3. der sehr stark fluorescierende distale Abschnitt des langen Arms. In dieser Arbeit wurden in Chromosomenpraparaten von 40 normalen Mannern mit verschieden langem Y-Chromosom Messungen dieser 3 Abschnitte durchgefuhrt. Es zeigte sich, das die Langenvariabilitat des Y-Chromosoms beim Menschen vor allem auf die wechselnde Grose des distalen, stark fluorescierenden Anteils des langen Arms zuruckzufuhren ist. Aber auch der proximale, schwach fluorescierende Teil des langen Arms zeigt eine gewisse Langenvariabilitat. Fur den kurzen Arm des Y-Chromosoms konnte in dieser Untersuchung keine statistisch gesicherte Langenvariabilitat gefunden werden.

Kidney function in experimental diabetic ketosis.

Abstract: Rats both with streptozotocin and alloxan diabetes were used. Ketosis developed in the first days following the application of the diabetogenic agents, and also in rats with long term diabetes in the first days after the insulin previously administered daily, had been withdrawn. The rats with more elevated blood ketone levels also demonstrated strikingly high serum urea levels, oliguria and a diminished food intake. In the groups of rats which in spite of insulin deficiency revealed no or only mild ketonaemia, food intake was increased, and marked polyuria as well as near to normal serum urea levels were observed. Our results showed that the symptoms of uraemia occurred independently of the nature of the diabetic agent, and also of the time at which these agents were administered. Thus it can be concluded that in that case acute renal insufficiency was not due to the nephrotoxicity of the agents employed but rather to the severity of diabetic ketosis.

Melanin Pigmentation: An in vivo Model for Studies of Melanosome Kinetics within Keratinocytes

Abstract: The phagocytosis of latex beads by epidermal cells is proposed as a model for stludies on melanosome kinetics within the epidermis. Large latex beads (0.8 micrometer) are ingested singly, whereas, small beads (0.1 micrometer) are taken up in groups, results showing that the uptake mechanism depends on the size of thze indlividual particles. This size-dependency may explain the different distribution patterns of melanosomes and thus the differences of skin color in the Caucasoid and Negroid races.

Thermodynamic properties and ordering in PdAl

Abstract: The activity of aluminum in the Pd-Al system was determined by an isopiestic method from 30 to 80 at pct Al between 1090° and 1490°K It shows a strong negative deviation from ideality, with a decrease in activity of aluminum of four orders of magnitude around the stoichiometric composition of PdAl The defect structure in the CsCl-structure PdAl compound has been determined by lattice parameter measurements Equations were derived relating the degree of intrinsic disorder (α) to the shape of the activity curve Excellent agreement between the calculated curve and the activity data was obtained for anα = 25 × 10−4 The results from this investigation and from previous studies indicate that the degree of intrinsic disorder in the equiatomic transition metal-aluminum compounds is controlled by electronic effects

Syntheseversuche in der Reihe der 3.6‐Epidithio‐2.5‐dioxo‐piperazin‐Antibiotika Gliotoxin, Sporidesmin, Aranotin und Chaetocin, II

Abstract: cis-3.6-Dimercapto-2.5-dioxo-1.4-dimethyl-piperazin (9) wurde durch stereospezifische Synthese aus 3.6-Dibrom-2.5-dioxo-1.4-dimethyl-piperazin (2) unbekannter Konfiguration uber die Reduktion des Epitetrasulfids 5 hergestellt. Die cis-Struktur wird durch Umwandlung in das Epitetrasulfid 5 und das Dithiocarbonat 7 bewiesen. Durch Grenzflachendehydrierung im System CHCl3/H2O-KJ3 erhielt man aus dem Dimercaptan 9 das Epidisulfid 8 mit dem charakteristischen Strukturmerkmal der antiviralen Antibiotika. Studies in the Synthesis of the Antibiotics Gliotoxin, Sporidesmin, Aranotin, and Chaetocin, II 3.6-Dibromo-.4-dimethyl-2.5-dioxopiperazine (2) — with unknown configuration — reacts with Na2S4 to give the epi-tetrasulfide 5. The latter is reduced with Na-boranate to cis-3.6-dimercapto-1.4-dimethyl-2.5-dioxopiperazine (9), whose configuration is derived from its generation and the ring closure reactions of the two mercapto groups which result in the formation of the epi-tetrasulfide 5 and the dithiocarbonate 7. Dehydrogenation of 9 at the interface of CHCl3/H2O-KJ3 produces the pure epi-disulfide 8 with the characteristic nucleus of Gliotoxin, Sporidesmin, Aranotin, and Chaetocin.

Immunofluorescence patterns in dermatitis herpetiformis. Investigations on skin and intestinal mucosa.

Abstract: Summary.— An attempt has been made to detect Ig deposits in skin and upper intestinal mucosa, and circulating antibodies in the serum, of patients with dermatitis herpetiformis. Deposits containing IgA and complement (C3’) were traced in the lesional skin of 11 of 12 patients. One patient wbo was free of skin symptoms failed to exhibit similar findings. Specimens of upper intestinal mucosa (9 patients), did not show a similar pattern of junctional IF; however a marked flattening of the mucosal relief was observed in 6 patients. Circulating antibodies against junctional antigens of skin or jejunal tissue were not demonstrated.

Typen des Mineralstoffwechsels bei den höheren Pflanzen

Abstract: Bezuglich der Rolle des Calciums im Mineralstoffhaushalt hoherer Pflanzen liesen sich zunachst Typen charakterisieren: 1. Oxalattyp: Enthalt nahezu das gesamte Ca in unloslicher Form als Oxalat; fallt aufgenommenes Ca durch stetige Neuproduktion von Oxalat aus. 2. Calciotropher Typ: Speichert hohe Konzentrationen loslicher Calciumverbindungen, enthalt vielfach mehr gelostes Ca als K. 3. Kaliumtyp: Enthalt im Vergleich zu K nur masige Mengen gelostes Ca.