Pressure induced changes in the Raman spectra of liquidn-alkanes and perfluoro-n-alkanes

1982

The main effect of pressures up to 6 kbar on the Raman spectra of liquidn-alkanes and perfluoro-n-alkanes is a reduction of line widths indicative for a slowing-down of rotational motions about the long axes. There is no evidence for a change in the conformer populations.

Gas chromatographic study of acetyl derivatives of chlorinated 4-hydroxybenzaldehydes

1982

The GC retention times of 4-hydroxybenzaldehyde and its chloro derivatives have been measured on three nonpolar capillary columns. Multiple linear regression analysis has been used to explain the mobility of chlorinated compounds relative to the reference compound 4-hydroxybenzaldehyde. The most important effects have shown to be due to the number of chlorine atoms and the substituents ortho to the formyl group. Other effects have also been observed but found to be unable to explain the GC data.

On the observability of parity and time reversal violating interactions by trapped ion spectroscopy

1982

The feasibility to measure neutral weak current interactions by spectroscopy on trapped ions is investigated. The sensitivity of the proposed experiment is compared to the sensitivity of similar experiments using atomic gases or beams. It is shown that there is no advantage as far as that part of the interaction is concerned which is a vector in the nucleon current and an axial vector in the electron current. This is mainly due to the relatively low ion density. The circular polarization however depending upon the nuclear spin orientation appears to be proportional to the coherence time, which is three orders of magnitude longer than in ordinary atomic beam resonance experiments. It is poin…

Electronic Properties of Point Defects in Metals

1982

Recent progress in electronic structure and related properties of point defects in metals is reviewed. Topics discussed include transition metal impurities in a non-magnetic host, construction of potential energy surfaces from effective-medium theories, trapping of light interstitials, and pair potential in metals.

Un nuevo anovulador antiandrogénico

1982

El acetato de Ciproterona solo o asociado con estrógenos es el producto idóneo para el tratamiento de manifestaciones androgénicas . El esquema terapéutico debe adaptarse al predominio, tiempo de evolución y severidad de unos u otros síntomas. Cuando se trata de hirsutismo moderado o grave la pauta será la administración del método continuo a dosis altas durante 6 meses, seguido de método combinado de altas o bajas dosis, según el tipo de respuesta inicial. Cuando predominan el acné y la seborrea se usará el método combinado de bajas dosis, pues si bien son mejores los resultados que se obtienen con el método continuo a dosis altas, los efectos secundarios no justifican su us…

Histological abnormalities in patients with multiple esophageal webs

1982

Two cases of multiple esophageal webs are presented. Histological evaluation of multiple esophageal biopsies revealed marked basal cell hyperplasia along the whole length of the esophagus. In one case these mucosal alterations remained unchanged during several years of follow-up.

In-beam studies of203, 205Bi and shell-model features of odd-a bismuth isotopes

1982

States in203, 205Bi are populated using the reaction203, 205Tl(3He,3n). Theπi13/2 single-proton states and all the members of thev(21+)⊗π h9/2 quintuplet are identified in both nuclei. The half-lives of the isomericJπ=21/2+ states in both isotopes are measured and found to be 90±7 ns and 100±6 ns, and from these values suggestions for the half-lives of the previously reportedJπ=25/2+ isomers are made. The structures of the multiplets of the formv(Pb)⊗π h9/2 are calculated in the framework of the shell model and it is shown that the main features can be derived from theπ−v−1 effective interaction. The wave functions of the 41+ and 40+ states in202, 204pb are deduced indirectly from the calcu…

Liposomes from α,ω-dipolar amphiphiles with a polymerizable diyne moiety in the hydrophobic chain

1982

Symmetric polymerizable α,ω-dipolar C22-diacetylenes were prepared by oxidative coupling of 10-undecynoic acid and 10-undecynol, respectively, by means of copper II salts in ethanolic solution. 10,12-Docosadiyne-1,22-diphosphate (3)—by reaction of 10,12-docosadiyne-1,22-diol (2) with POCl3—was polymerized in aqueous solution using UV irradiation to form deep blue, thermochromic solutions. By consonication of 3 with cholesterol, monolayer vesicles were formed. This was proven by encapsulation of 6-carboxyfluorescein. These monomeric vesicles were polymerized by UV light to yield stable, deep blue polymeric vesicle suspensions.

An in vitro model for the study of human parathyroid gland tissue: Single cell suspensions and monolayer cultures

1982

An in vitro model for studies of parathyroid physiology is described using single cell suspensions and adherent monolayer cultures of human parathyroid tissue. The isolated cells were viable and maintained functional properties tested by calcium and magnesium sensitivity. Parathyroid hormone (PTH) secretion could be suppressed by rising calcium and magnesium concentrations. The secretory behaviour of the cells was not altered by cultivation or cryopreservation. The morphological integrity of the individual cells after mechanical and enzymatic preparation was confirmed by light and electron microscopy.

Una solucion bayesiana a la Paradoja de Stein

1982

If we are interested in making inferences about the square norm of the mean in a multivariate normal model, the usual uniform prior for the mean is not sound, as revealed by Stein in his 1959 work. This paper studies in what sense this prior must be modified by using the maximization of missing information procedure (Bernardo, 1979)

Der Einflu� von Sonographie und Computer-Tomographie auf die operative Behandlung der akuten Pankreatitis

1982

Die „stadiengerechte Therapie” der akuten Pankreatitis, die jedem Schweregrad der Erkrankung angemessen ist, besteht neben der konservativen Basistherapie und Intensivmedizin im richtigen Einsatz operativer Masnahmen. Voraussetzung dafur ist die fruhe Diagnose und Beurteilung des Schweregrades der akuten Pankreatitis. Neben klinischen und klinisch-chemischen Befunden und dem Verlauf unter konservativer Therapie ermoglichen die Sonographie und die Computer-Tomographie eine bessere Beurteilung der jeweiligen Verlaufsform. Die fur die Klinik der Erkrankung so wichtigen morphologischen Veranderungen der Bauchspeicheldruse und ihrer Umgebung werden durch diese neuartigen Untersuchungsmethoden tr…

Discussion of “Shakedown under Elastic Support Conditions”

1982

Neue Aspekte der Amyloidose

1982

Amyloid ist eine Substanz, die sich in ihren Grundeigenschaften bei allen Formen der Amyloidose gleichartig zusammensetzt. Aufgrund elektronenmikroskopischer Untersuchungen zeigt sich, das alle Amyloidosen nicht nur einheitliche Grundeigenschaften, sondern auch ein gemeinsames Ablagerungsprinzip aufweisen. Amyloidfibrillen finden sich immer in enger Beziehung zu Basalmembranen bzw. basalmembranartigen Substanzen, insbesondere von Zellen mit kontraktilen Eigenschaften (myozytare oder myopotente Zellen). Kollagene Fasern verschiedenen Typs weisen keine geregelte Beziehung zur Amyloidsubstanz auf. Die Entstehung und Entwicklung der Amyloidosen ist weiterhin abhangig von folgenden drei Faktoren…

Studies on the mechanism of PMN activation. I. By dextran sulfates.

1982

Evidence is presented that enhanced reduction of the dye nitroblue-tetrazolium (NBT) by polymorphonuclear leukocytes (PMN) which are stimulated by dextran sulfates (DS) is not exclusively due to the phagocytosis of particles formed by NBT and DS. Not only the size of phagocytizable particles but the degree of substitution determines the acceleration of NBT-reduction. A likely cause of this acceleration is the triggering of the alternative pathway of the complement activation.

ATPase Aktivität und Natriumtransport an Erythrocyten bei essentieller Hypertonie

1982

Die Geschwindigkeitskonstante des „Gesamt“ Natriumefflux aus Erythrocyten war bei Patienten mit essentieller Hypertonie im Vergleich zu einem normotonen Kontrollkollektiv erniedrigt und beruhte auf einem verminderten „Ouabain-abhangigen“ (aktiven) Natriumtransport. Die Geschwindigkeitskonstanten des „Ouabain-unabhangigen“, des „Ouabain-unabhangigen Furosemid-abhangigen“ und des „Ouabain-unabhangigen Furosemid-unabhangigen“ Natriumefflux waren bei Hypertonikern und Normotonikern gleich. Ouabain hemmte bei beiden Kollektiven den Natriumefflux um rund 74%, Furosemid um weitere 13%. Der verminderte aktive Natriumtransport an Erythrocyten essentieller Hypertoniker ging mit einer erniedrigten Na-…

Core Polarizabilities in Metals

1982

Linear response formalism within the density-functional scheme is applied in a calculation of core polarizabilities in simple metals. While the core polarizability changes relatively little (around 10%) from its free-ion value in the alkalis, Mg and Al, large increases are found for metals like Ga, Cd, In, and Sn with full d-shells. Low-frequency values for the dynamic polarizability are also obtained.

Density-Functional Calculations of Auger and X-Ray Photoemission Shifts for Metallic Elements

1982

ΔSCF density-functional calculations are reported for Auger, and core level binding energy shifts in sp-bonded metals. The basic model, atom-in-jellium-vacancy, gives good agreement with experiment, especially in the Auger case. The chemical and relaxation contributions to the shifts are discussed. The shifts are calculated also by using the thermochemical model and the results obtained are in agreement with experimental data. The applicability of the "excited-atom" approach to the Auger energy shifts is found restricted.

Contracting striated muscle fibres differentiated from primary rat pituitary cultures.

1982

Whole pituitaries or adenohypophyses alone of adult female Wistar/ Furth rats were dissociated into single cells by means of two different enzymic disintegration methods. The single-cell suspension was then seeded out and cultured for up to 8 months in tissue culture dishes with untreated and polylysine coated surfaces. The cells were cultured in different sera (horse serum, newborn-calf serum, fetal-calf serum, mixtures of horse and newborn-calf serum, and isogenic rat serum) and also in a serum-free, hormone-supplemented medium. When the cells were cultured in medium containing horse serum (15 %) plus fetal-calf serum (3%) on polylysine-treated surfaces, cell fusion and the development of…

IUT de gestion des entreprises : analyse de la population, de la sélection en cours d'études, de la sélection à l'entrée

1982

International audience

Estimations de probabilités d'accès aux seconds cycles de l'enseignement secondaire à l'issue de la classe de 3ème

1982

International audience

Analyse des procédures d'orientation au palier de 3ème

1982

International audience

false

1982

The molecular weight distribution (MWD) of a high polymer is calculated from a weakly perturbed Zimm-plot of the classical light scattering on dilute solutions of Gaussian polymer coils (theta state). A typical Zimm-plot is simulated corresponding to the measurements of high accuracy as would be obtained by using the laser photometer described by Hack and Meyerhoff. The accuracy as published by these authors for small dissymmetries is used. Two numerical methods for calculating the MWD are briefly described and tested, both using an empirical formula for the Laplace image of the calculated MWD.

false

1982

The electro-optical properties of liquid crystalline polymers with polar mesogenic units in the side chain were investigated. It could be shown, that in an electric field, they show all effects known from low molecular weight liquid crystals, e.g. the Freedericksz-transition, the DAP-effect, the formation of William's domain, and the dynamic scattering. The optical response times are slightly longer than for low molecular weight liquid crystals, but in some cases at higher temperatures as short as 200 ms. By comparison of different polymers and some corresponding liquid crystalline monomers, it is found that: (1) the difference between the measuring temperature and the glass transition temp…

false

1982

The molecular weight distribution (MWD) of a high polymer is calculated from a weakly perturbed Zimm-plot of the classical light scattering on dilute solutions of Gaussian polymer coils (theta state). A typical Zimm-plot is simulated corresponding to the measurements of high accuracy as would be obtained by using the laser photometer described by Hack and Meyerhoff. The accuracy as published by these authors for small dissymmetries is used. Two inversion procedures are described in detail and tested, both of them avoiding the use of an empirical formula for the Laplace image of the calculated MWD. A complete numerical analysis of the results is given. The results are compared with those of …

false

1982

false

1982

Frequency Dependence of the Orientational Freezing in(KBr)1−x(KCN)x

1982

Dielectric, ultrasonic, and neutron-scattering measurements in ${(\mathrm{KBr})}_{1\ensuremath{-}x}{(\mathrm{KCN})}_{x}$ are reported for concentrations $x$ ranging from 0.01 to 0.5. The dipolar and the quadrupolar susceptibilities exhibit frequency- and concentration-dependent cusps showing that the freezing process into an orientational glass state is a relaxational phenomenon.

Studies on the synthesis of heterocyclic compounds. Part VIII. A facile synthesis of new pyrazolo[3,4-b]benzazepine-4,9-diones

1982

2-Carbomethoxybenzoyl chloride reacted with some 5-methylamino-l-phenyl-3-R-pyrazoles to yield N-methyl-l-phenyl-3-R-pyrazol-5-yl)-2-carbomethoxybenzamides. These products were readily transformed into the corresponding acid, which in turn, refluxed in phosphorus oxychloride afforded the tricyclic system, l-phenyl-3-R-pyrazolo[3,4-b]benzazepine-4,9-dione.

Polymerization of ethylene in the presence of organometallic complexes formed by chloroisopropoxytitanium compounds and sesquiethylchloroaluminium

1982

The catalytic activity of organometallic complexes obtained from chloroisopropoxytitanium compounds and sesquiethylchloroaluminium has been studied. The complexes are active as catalysts for polymerization of ethylene, living high molecular weight product with high output. It is found that the molar ratio of catalyst components affects the output and molecular weight of polyethylene. The optimum molar ratiofor three catalytic systems is given.

Quantitative Bestimmung von Trichothecenen HT-2 Toxin in verschimmelten pflanzlichen Nahrungsmitteln

1982

Es wird ein Verfahren zur quantitativen Bestimmung von HT-2 Toxin in verschimmeltem Reis, Mais, Weizen, Hafer, Roggen bzw. Erbsen beschrieben. Extrahiert wurde mit einer Mischung von 9 Teilen (Volumen) Acetonitril und einem Teil wasriger 4%iger KCl-Losung. Die Extrakte musten teilweise chromatographisch vorgereinigt werden. Die terminale Bestimmung erfolgte nach zweidimensionaler dunnschichtchromatographischer Trennung durch Fluorescenzintensitatsmessung der mit H2SO4 behandelten DC-Platten. Versuche mit zugesetztem HT-2 Toxin ergaben eine Wiederfindung von 88% (Variationskoeffizient 7).

?-Carboline binding indicates the presence of benzodiazepine receptor subclasses in the bovine central nervous system

1982

Receptor binding studies were performed with tritiated propyl β-carboline-3-carboxylate ([3H]PrCC), tritiated ethyl β-carboline-3-carboxylate ([3H]ECC), and tritiated flunitrazepam ([3H]FNT) in membrane preparations from different regions of the bovine brain and retina. Specific binding in all regions investigated was associated with benzodiazepine receptor sites. However, not all benzodiazepine receptor sites. However, not all benzodiazepine receptors in the regions investigated as determined by the specific binding of tritiated flunitrazepam ([3H]FNT) are available for [3H]PrCC suggesting that specific [3H]PrCC binding labels only one subclass or subpopulation of the benzodiazepine recept…

Localization of segmental arteries in renal surgery by Doppler sonography.

1982

Abstract To avoid damage to major arteries of the renal parenchyma during nephrotomy, intraoperative Doppler sonography was used experimentally and clinically as an artery finder. In experiments with 7 beagles segmental arteries were detected easily and reliably by sonography, and the arterial course thus indicated correlated perfectly with arteriograms and casts. In a clinical trial the Doppler artery finder was used in 7 patients with staghorn calculi that were removed via the renal pelvis and additional multiple selective nephrotomies. With as many as 7 selective nephrotomies in a single kidney there was no damage to the major arteries in any of these patients. Selective, avascular nephr…

On the mechanism of fibril growth in polycarbonate and poly(methyl methacrylate) crazes

1982

Search for superheavy elements in monazites using chemical enrichment

1982

Evidence for the existence of superheavy elements in monazite inclusions embedded in Madagascan mica and surrounded by giant radioactive haloes was given by Gentry et al.1 who observed photons with energies corresponding to predicted Lα1 X-ray energies of element 126 (at 27.25 keV) and also of elements 116, 124 and 127 in irradiations of such crystals with collimated proton beams. For an unambiguous identification, the detection of further members of the L X-ray series would be most important. In X-ray spectra of monazite samples these transitions are buried under the strong K X-ray peaks of the lanthanide elements. They should, however, become visible after chemical enrichment of the super…

The anaerobic metabolism of malate of Saccharomyces bailii and the partial purification and characterization of malic enzyme.

1982

1. The main pathway of the anaerobic metabolism of l-malate in Saccharomyces bailii is catalyzed by a l-malic enzyme. 2. The enzyme was purified more than 300-fold. During the purification procedure fumarase and pyruvate decarboxylase were removed completely, and malate dehydrogenase and oxalacetate decarboxylase were removed to a very large extent. 3. Manganese ions are not required for the reaction of malic enzyme of Saccharomyces bailii, but the activity of the enzyme is increased by manganese. 4. The reaction of l-malic enzyme proceeds with the coenzymes NAD and (to a lesser extent) NADP. 5. The Km-values of the malic enzyme of Saccharomyces bailii were 10 mM for l-malate and 0.1 mM for…

Parity-violating effects in electroproduction of theΔ(1232)by polarized electrons

1982

Parity-violating effects in the (quasi)elastic scattering of longitudinally polarized electrons from spin-\textonehalf{} targets are discussed in the framework of the unified guage theories of weak and electromagnetic interactions. In particular, the $R\ensuremath{-}L$ asymmetry in electroproduction of the $\ensuremath{\Delta}(1232)$ is studied in considerable detail, taking into account the full spin-$\frac{3}{2}$ structure of this resonance. Our results are valid for all values of $E$ and the entire range of ${Q}^{2}$. Numerical predictions are given for the standard Weinberg-Salam model at several energies of the electron beam.