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Notizen: Highly resolved (Δν〈100 MHz) UV-REMPI (ultraviolet-resonantly enhanced multiphoton ionization) spectra of different vibronic bands in the phenol–water complex are presented. The torsional splitting caused by the hindered rotation of the water moiety in the hydrogen-bonded system is investigated. An autocorrelation procedure reveals torsional subbands, a correlation automated rotational fitting (CARF) of the spectra yields the rotational constants: The analyzed vibrations are classified by the rotational constants of the corresponding vibronic band and the symmetry of the torsional state. The transition to the stretching vibration at 156 cm−1 excess energy is shown to consist of two different torsional transitions similar to the electronic origin. The torsional splitting in the origin band is 0.8491(2) cm−1 and that of the stretching vibration is 0.8915(3) cm−1, demonstrating a very small coupling between the stretching and the torsional motion. We assign the 121 cm−1 band as the negative parity component of the transition to the wagging vibration β2 while the band at 125 cm−1 is tentatively assigned as the positive parity component of the same band. The resulting large torsional splitting of −4.596(3) cm−1 points to a strong coupling to the torsional motion. The band at 95 cm−1 has only one torsional parity component within its rotational envelope. The observed large change of its rotational constants does not fit to the pattern of the other vibrations and the band is tentatively assigned as an overtone of the torsional vibration τ with positive parity. © 1998 American Institute of Physics.

Notizen: Abstract— Human brain-specific alpha2-glycoprotein was purified by means of Sepharose immunoadsorbents. A further brain-specific protein was found by this method. This component appears to be present in brain in low concentrations only and has been enriched by affinity chromatography. Glial cells of human brain were separated from neurons by a density centrifugation method and four fractions were obtained: neuropil, neuronal perikarya, nuclei and debris. Each fraction was checked by light and phase contrast microscopy to estimate the intactness of the cells and any contamination by other fractions, and also immunologically for determination of brain-specific alpha2-glyco-protein. The results indicate that localization of this brain-specific protein is in the cyto-plasm of the glial cells. The results are discussed in terms of a possible role of this protein in the inflammatory response and in some demyelinating diseases.

Notizen: We investigated the possibility of inferring effective hydraulic properties of soil from the structure of the pore space. The aim was to identify structural properties, which are essential for water flow, so that physical experiments may be replaced by direct morphological measurements. The pore structure was investigated in three dimensions by serial sections through impregnated samples. The complex geometry of pore space was quantified in terms of two characteristics: pore-size distribution and pore connectivity. Only pores larger than 0.04 mm were considered. The results were used as input parameters for a pore-scale network model. The main desorption branch of the soil-water characteristic and the corresponding hydraulic conductivity function of the network model were calculated by numerical simulation. The simulation results, which are exclusively based on morphological investigations, were compared with independently measured results from a multi-step outflow experiment. This approach was demonstrated for two centrasting soil materials: the A and B horizons of a silty agricultural soil. The simulations were close to the experimental data, except for the absolute values of the hydraulic conductivity. The pore-size distribution and pore connectivity govern the shape of hydraulic functions and the applied morphometric methods are suitable for predicting essential characteristics of hydraulic soil properties.

Notizen: The geometry of pore space in soil is considered to be the key in understanding transport of water, gas and solute. However, a quantitative and explicit characterization, by means of a physical interpretation, is difficult because of the geometric complexity of soil structure.Pores larger than 40 μm within two soil horizons have been analysed morphologically on 3-dimensional digital representations of the pore space obtained by serial sections through impregnated specimens. The Euler-Poincaré characteristic has been determined as an index of connectivity in three dimensions. The pore connectivity is quantified as a function of the minimum pore diameter considered leading to a connectivity function of the pore space. Different pore size classes were distinguished using 3-dimensional erosion and dilation. The connectivity function turned out to differentiate between two soil materials. The pore space in an upper Ah horizon is intensely connected through pores between 40 and 100 μm, in contrast to the pore space in the AhBv beneath it. The morphological pore-size distributions were compared to the pore-size distribution obtained by water retention measurements. The discrepancy between these different methods corresponds to the expectation due to pore connectivity.

Notizen: Die Gestalt der Uterindrüsen der Stute wird nadi Mazeration in Eisessig und nach Prepäration in Glycerin räumlich dargestellt. Ihr zyklusabhängiger Formenwandel sowie das für das Stutenendometrium charakteristische hohe Stratum subglandulare werden diskutiert. In einer vergleichenden Betrachtung wird die Drüsenhyperplasie im Postoestrum bei alien Haussäugetieren und beim Menschen herausgestellt. Bei der Maus liegt dagegen eine Drüsenhypertrophie im Oestrum vor.〈section xml:id="abs1-2"〉〈title type="main"〉SummaryCyclic changes in the shape of the mare's uterine glands compared with those of other mammals and manAfter maceration in glacial acetic acid and dissection under glycerin the shape of the mare's uterine glands is demonstrated three-dimensionally. Their changes in shape and size, related to the estrous cycle, and the thick subglandular layer, characteristic of the mare's endometrium, are discussed. Glandular hyperplasia occurs in the postestrous period in all domestic mammals and in man. In the mouse however there is glandular hypertrophy during estrus.〈section xml:id="abs1-3"〉〈title type="main"〉RésuméLes changements de forme cycliques des glandes utérines de la Jument, comparés à ceux des autres Mammifères et de l'HommeAprès macération dans l'acide acétique glacial et préparation dans la glycérine, la forme des glandes utérines de la Jument a été représentée dans l'espace. Leurs changements de forme, liés au cycle, ainsi que le Stratum subglandulare, élevé, caractéristique de l'endomètre de la Jument, sont discutés. Dans une étude comparée, l'hyperplasie glandulaire au Postoestrus est mise en évidence chez tous les Mammifères domestiques et chez l'Homme. Chez la Souris, par contre, c'est à l'Oestrus qu'on observe une hypertrophic glandulaire.〈section xml:id="abs1-4"〉〈title type="main"〉ResumenLos cambios ciclicos en la forma de las glándulas uterinas de la yegua en comparación con los de otros mamíferos y del hombreMediante la maceración en ácido acético glacial y la preparación en glicerina, se demuestran las glándulas uterinas en forma tridimensional. Se discute su cambio cíclico y su capa subglandular (Stratum subglandulare) característica para el endometrio de la yegua. Un estudio comparado de los animates domésticos y del hombre destaca la hiperplasia de las glándulas durante el postestro. En el ratón, al contrario, la hipertrofia glandular se encuentra durante el estro.

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