The isolation from a unicellular organism, Dictyostelium discoideum, of a highly-related cdc2 gene with characteristics of the PCTAIRE subfamily

Hepatocyte growth factor (HGF) is known to induce the dispersion of epithelial cells, as scatter factor. On the other hand, cadherins play a crucial role in connecting cells together. Two groups of cadherins are involved in epithelial cell adhesion, those locating in adherens junctions (AJ) and in desmosomes. Here, we examined the effect of HGF on the function of these cadherins in keratinocyte cell lines F and 308R, which expressed E- and P-cadherin in AJ (referred to as AJ cadherins) and desmoplakin in desmosomes. In the presence of HGF, these cells spread more extensively than in control cultures and their associations apparently loosened. However, they maintained cell-cell contacts where cadherins and desmoplakin concentrated, although the level of the concentration was reduced by HGF treatment. When antibodies to E- and P-cadherins were added to cultures of these cells without HGF, AJ cadherins were redistributed into non-junctional areas of the cells, but desmoplakin still localized at cell-cell boundaries. When HGF was added together with anti-AJ cadherin antibodies to the cultures, cell-cell contacts were now disrupted. In these cultures, not only AJ cadherins but also desmoplakin were lost at cell-cell contact sites, indicating that HGF can disrupt desmosomal cell-cell adhesion when AJ cadherins are inactive. These results suggest that, although HGF cannot block cadherin-mediated cell-cell adhesion when the entire cadherin system is intact, it might modulate the activities of cadherins, especially, of desmosomal cadherins.     

Multisource-sputtered ErBa2Cu3O7−x films on single-crystal and buffered crystalline substrates

High-quality superconducting films of erbium-barium-copper-oxide have been produced in a multisource sputtering system on a variety of substrates, including buffered sapphire and silicon wafers as well as various single-crystal materials. Fine-grained polycrystalline films with narrow (<4 K) resistive transitions have been grown on a number of different substrates. The use of erbium in the 12–3 compound leads to improved film morphology and to more forgiving conditions for establishing of the superconducting phase. Sputtered neutral mass spectroscopy (SNMS) yields useful information about the compositional profile of the films.     

Assessment of the Rescorla-Wagner model.

The Rescorla-Wagner model has been the most influential theory of associative learning to emerge from the study of animal behavior over the last 25 years. Recently, equivalence to this model has become a benchmark in assessing connectionist models, with such equivalence often achieved by incorporating the Widrow-Hoff delta rule. This article presents the Rescorla-Wagner model's basic assumptions, reviews some of the model's predictive successes and failures, relates the failures to the model's assumptions, and discusses the model's heuristic value. It is concluded that the model has had a positive influence on the study of simple associative learning by stimulating research and contributing to new model development. However, this benefit should neither lead to the model being regarded as inherently "correct" nor imply that its predictions can be profitably used to assess other models. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Agronomical and bromatological studies in jicama (Polymnia sonchifolia Poep et Endl.)]

An analysis of tuber roots yield and nutritional characteristics for 10 lines of jícama (Polymnia sonchifolia Poepp et Endl.) was carried out under the environmental conditions of Santa Catalina Experimental Station (12 degrees C of temperature and 3,100 m above sea level). The following average mean values were obtained: A fresh tuber root's yield from 29,755 to 73,558 kg/ha with 41,547 kg/ha of average, while the yield of the useful part (roots without skin) was from 24,309 to 60,097 kg/ha with 33,944 kg/ha of average. On the other hand, average mean values of 3.7% of protein, 3.5% ashes, 1.5% fat, 3.4% fiber, 2.2% potassium, 0.12% phosphorus, 96 micrograms/100 g iron, and 390 micrograms/100 g zinc, were obtained from the edible root samples. Besides, we obtained average values of 2.47, 2.12, 1.63 and 2.51 g/100 g of fructose, alfa glucose, beta glucose and saccharose, respectively, on edible root samples with skin, for the 10 lines studied. All these analyses were reported on a dry basis.     

Inbreeding in Swiss Braunvieh and its influence on breeding values predicted from a repeatability animal model.

Inbreeding coefficients were computed for 910,444 animals of the Swiss Braunvieh population. Of the animals born in 1984, 71.5% were inbred with 67.9, 3.4, and .2% having inbreeding coefficients between greater than 0 and 5%, greater than 5 to 10%, and greater than 10%, respectively. The average inbreeding coefficient was 1.14% but, for animals with both parents and at least one grandparent known, it was 1.67%. Breeding values for total milk, fat, and protein yields and for fat and protein percentages were predicted using a repeatability animal model including a regression on the inbreeding coefficient. Phenotypic performance was sizeably depressed for milk yield only (-26 kg/% of inbreeding or 2.4% of the phenotypic standard deviation). Adjusting for inbreeding increased the estimated genetic trend slightly. Inbreeding is only partially accounted for when it is ignored in the construction of the inverse of the numerator relationship matrix. This effect was investigated by comparing predicted breeding values from a model including the complete matrix with predicted breeding values from a model including a matrix constructed with inbreeding ignored. Only .8% of all predicted breeding values were affected by more than +/- 5.5 kg. The maximum difference observed was 55.3 kg. The observed average absolute differences between the breeding values of offspring predicted with the two models increased with inbreeding of parents.     

The Hg (Mercury) system

An erratum to this article is available at .     

The thermal ignition of lignocellulosics in infinite slab and cubic geometries

Wood shaving samples were heated in both cubic baskets and in a previously described system realising the conditions of the ‘infinite slab’ in thermal ignition. Results from the two sets of experiment were found to be totally consistent with each other.     

Visualizing the topography of coating surfaces

An optical system for imaging the topography of (coating) surfaces using a video monitor is described. The grey level of the image correlates with the slope of the surface. The principle of operation of the method is explained and some applications are indicated.