Compatibilization of immiscible poly(<Emphasis Type="Italic">l</Emphasis>-lactide) and low density polyethylene blends

Blends of poly(l-lactide) (PLA) and low density polyethylene (LDPE) were prepared by melt mixing in order to improve the brittleness of PLA. A reactive compatibilizer with glycidyl methacrylate (GMA), PE-GMA, was required as a compatibilizer due to the immiscibility between PLA and LDPE. It contributes to reduce the domain size of dispersed phase and enhance the tensile properties of PLA/LDPE blends, especially for PLA matrix blends. A reaction product between PLA and PE-GMA, which was formed during melt-mixing and considered to act as a reactive compatibilizer, was characterized using¹H-NMR spectroscopy.     

Approaches toward soil mapping of urban territories with the city of perm as an example

The diversity of urban soils and technogenic surface formations (TSFs) in the city of Perm is predetermined by the diverse lithologic and geomorphic conditions; different types of land use (residential areas with low-rise and multistory buildings, industrial zones, and agricultural zones) further enhance it. The soil cover of Perm has a mosaic pattern with contrasting changes in the morphology and genesis of its components. The areas of separate soils and TSFs cannot be delineated upon medium- and even large-scale mapping of the territory. We suggest that urban pedocomplexes—combinations of soils and TSFs developing within a given functional zone of the city from the same parent materials—should be shown on the map. Urban pedocomplexes differ from one another in the character of the predominant soils and TSFs. They inherit some features from the natural soils and parent materials and are transformed under the impact of the major type of land use.     

Report on a hogget ill-thrift trial

A method of cannulating the small intestine of the calf is described. Indwelling cannulas gave direct access to the intestinal lumen and mucosa, providing direct study of intestinal function and morphology.     

The expression of Clostridium perfringens consensus beta2 toxin is associated with bovine enterotoxaemia syndrome

Clostridium perfringens has been implicated in a broad array of enteric infections including the fatal haemorrhagic enteritis/enterotoxaemia syndrome in cattle. The beta2 toxin (CPB2), encoded by cpb2, is suspected to be implicated in this syndrome. However, among C. perfringens isolates from cattle suspected of clostridial disease, an atypical allele was recently found to predominate at the cpb2 locus and atypical corresponding CPB2 proteins were shown to be poorly expressed, thus arguing against a biologically significant role of the beta2 toxin in clostridial diseases in cattle. This study compared genotype and phenotype of the beta2 toxin between C. perfringens isolates from a group of healthy calves (n=14, 87 isolates) and from a group of enterotoxaemic calves (n=8, 41 isolates). PCR results revealed the exclusive presence of the typical "consensus"cpb2 in the enterotoxaemic group. Western blot analysis demonstrated that the typical variant of CPB2 was often expressed in isolates from enterotoxaemic calves (43.9%) and infrequently in isolates from healthy cattle (6.9%). These data suggest that the typical variant of the CPB2 toxin may play a role in the pathogenesis of cattle enterotoxaemia.