On the Ecology and Distribution of Echinococcus spp. (Cestoda: Taeniidae), and Characteristics of Their Development in the Intermediate Host. II. Comparative Studies on the Development of Larval E. multilocularis Leuckart, 1863, in the Intermediate Host

This paper reports the results of a comparative study of the development of the larval Echinococcus multilocularis Leuckart, 1863), and associated tissue reaction in naturally and experimentally infected mammals representing 31 species. The histogenesis of the larval cestode was traced in detail in arvicoline rodents of several species, and interspecific differences were defined. In arvicoline rodents, the developing larva exhibited host-specific characteristics within about a month after infection was established. The tissue reaction in Microtus oeconomus was characterized by the production of a large quantity of detritus around the larva, and by the formation of a thick epithelioid zone. In one subspecies, M. oeconomus innuitus, development of the larva was retarded, and the detrital mass was often calcified; in another, M. oeconomus operarius, the detritus rarely became calcified and the larva proliferated more rapidly. In M. pennsylvanicus, the tissue reaction was minimal, and little detritus was present. The characteristics of the tissue reaction in M. montebelli placed it in an intermediate position between the aforementioned species. In Clethrionomys rutilus, a thin epithelioid zone and an outer zone of loose collagenous fibers composed the adventitial layer; exogenous budding was retarded in this vole. A minimal tissue reaction occurred in Lagurus curtatus. In Lemmus spp., larger cysts were characteristic, but areas of small-cystic proliferation were always present. Similar differences in species or subspecies of Citellus and Dicrostonyx were described. Lesions of alveolar bydatid disease in man also were studied. The invasive growth of the larval cestode in the human liver involves a process comparable to small-cystic proliferation in the natural intermediate hosts. Although the later stages of development of the larval cestode are inhibited in man, exogenous proliferation of vesicles continues for the life of the host. The lesion in man was compared with a morphologically similar formation produced by anomalous development of the larval E. granulosus in the bovine liver. The latter is distinguished by the absence of areas of small-cystic proliferation. Non-echinococcal lesions found in the tissues studied, some of which resembled foci caused by the larval E. multilocularis, were briefly discussed.

Comparative Anylysis of Recyling Programs: A Case Study of Three Universities

Abstract The goal of this study was to conduct a comparative analysis of three university recycling programs. This study looked at several aspects of the programs that included the diversion rates, per capita ratios of materials recycled and disposed, and the average net costs of waste disposal and waste diversion. The universities included in this study were the University of Nebraska-Lincoln, the University of Colorado at Boulder, and the University of Oregon. To gather the information necessary for this analysis, I contacted each of the university’s recycling coordinators. To determine the average net costs of waste disposal and waste diversion I requested both the recycling budget and solid waste budget from each university for the fiscal years of interest which included: 2006-2007, 2007-2008, and 2008-2009. To calculate the diversion rates and per capita ratios, I requested performance records from each university listing the tonnage of materials recycled and disposed for the same years. This study’s findings reported that the average net costs for waste diversion in all three universities were $22-$122 less per ton than costs for waste collection and disposal. This study also indicated that the universities with the highest diversion and recycling rates were the University of Colorado at Boulder and the University of Oregon. The university with the lowest waste generated per capita was the University of Oregon followed by the University of Nebraska-Lincoln.