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Notes: 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.

Notes: The food dye Brilliant Blue FCF (Color Index 42090) is often used as dye tracer in field studies for visualizing the flow pathways of water in soils. Batch studies confirmed findings of other researchers that non-linear sorption is important for Brilliant Blue, especially at small concentrations (〈 10 g l−1 for our soil), and that retardation increases with decreasing concentrations as well as with increasing ionic strength of solutions. Therefore, it is not obvious if it can be used as an indicator for water flow paths as is often done. In this study, we compared the mobility of Brilliant Blue in a field soil (gleyic Luvisol) with that of bromide. Brilliant Blue and potassium bromide were simultaneously applied as a 6-mm pulse on a small plot in the field, and the tracers were displaced with 89 mm of tracer-free water using a constant intensity of 3.9 ± 0.2 mm hour−1. Both tracer concentrations were determined on 144 soil cores taken from a 1 m × 1 m vertical soil profile. The transport behaviour differed in both (i) mean displacement and (ii) spatial concentration pattern. We found the retardation of Brilliant Blue could not be neglected and, in contrast to the bromide pattern, a pulse splitting was observed at the plough pan. Numerical simulations with a particle tracking code revealed that the one-dimensional concentration profile of bromide was represented fairly well by the model, but the prediction of the double peak in the Brilliant Blue concentration profile failed. With additional assumptions, there were indications that Brilliant Blue does not follow the same flow paths as bromide. However, the question of Brilliant Blue taking the same flow pathways as bromide cannot be adequately answered by comparing both concentration distributions, because we look at two different transport distances due to the retardation of Brilliant Blue. It became obvious, however, that Brilliant Blue is not a suitable compound for tracing the travel time of water itself.

Notes: The inability to predict flow and transport behaviour based on a priori information demonstrates the lack of knowledge we currently have concerning transport-relevant properties or processes, or both. We present an approach in which the behaviour of effective solute transport at the scale of a soil column (100 mm) is predicted by taking into account the spatial structure of the hydraulic properties at the local scale (1 mm). The local absorption coefficients obtained from X-ray tomography, which are linearly related to bulk density, are used as local proxy for hydraulic properties. As a first approximation, two density classes were distinguished, and the three-dimensional structure of the hydraulic properties was implemented in a model of flow and transport. The local hydraulic properties were obtained from a network model, except for the absolute value of the hydraulic conductivity function which was measured. Model simulations were compared with a measured breakthrough curve determined on the same soil sample. The two agreed well, although the local hydraulic properties and parameter structure were determined independently with respect to a breakthrough experiment. Predictions of solute transport at the column scale were sensitive to the difference in saturated hydraulic conductivities of both materials, but not to the local dispersivities. The simulations demonstrate that (i) assuming validity of the Richards equation and the convection–dispersion equation on the local scale leads to a good description of the effective flow and transport behaviour at the column scale without making any assumptions about the governing processes at that scale; (ii) the dispersion parameters, which are notoriously difficult to determine, need not be determined since their effect is included explicitly; and (iii) local absorption coefficients can be used as a local proxy for the parameter field of the hydraulic properties.

Notes: Network models are idealized geometrical representations of porous media. They allow the simulation of effective hydraulic properties and of solute transport for well-defined porous structures. In this paper, the relation between pore structure and effective properties is studied using a network model which can be adjusted to predefined pore-size distributions and pore topologies. I show that pore topology can be adjusted such that quite different pore-size distributions lead to essentially identical water retention curves. This puts into question the common interpretation of the retention curve as being indicative of the pore-size distribution. However, I also found that both the hydraulic conductivity and the dispersion of a solute depend on the water retention curve and not on the particular combination of pore-size distribution and topology which make it up. This corroborates the widely used approach of inferring relative permeabilities from water retention data.

Notes: The quantification of the spatial heterogeneity of soil structure is one of the main difficulties to overcome for an adequate understanding of soil processes. There are different competing concepts for the type of heterogeneity, including macroscopic homogeneity, discrete hierarchy or fractal. With respect to these different concepts we investigate the structure of the pore space in one single sample (4 × 103 mm3) by analysing basic geometric quantities of the pores 〉 0.3 mm within gradually increasing subsamples. To demonstrate the relation between geometrical and functional properties we simulate gas diffusion within the three-dimensional pore space of the different subsamples. An efficient tool to determine the geometric quantities is presented. As a result, no representative elementary volume (REV) is found in terms of pore-volume density which increases with sample size. The same is true for the simulated gas diffusion coefficient. This effect is explained by two different types of pores, i.e. big root channels and smaller pores, having different levels of organization. We discuss the different concepts of structural organization which may be appropriate models for the structure investigated. We argue that the discrete hierarchical approach is the most profitable in practice.

Notes: We report a woman with recessive dystrophic epidermolysis bullosa (RDEB) in whom there was prolonged sepsis and death at age 22 years. Autopsy revealed multiple epidermolytic skin lesions with chronic ulceration, mesangioproliferative glomerulonephritis and multifocal necrotizing leucoencephalopathy (MNL) of the pons. The latter two conditions may have been mediated by sepsis-associated cytokines. Although mesangioproliferative glomerulonephritis has previously been described in association with RDEB, to our knowledge this is the first report of MNL in a patient with RDEB.

Notes: 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.

Notes: DISKUSSION