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471.
ELDON D. SMITH 《Growth and change》1990,21(4):3-18
Approaches for analyzing employment stability with aggregated data for SICs in large regions or major metropolitan areas are misleading indicators of the impact of manufacturing growth in rural areas. Performance of moderate-sized individual establishments seriously impact total employment variation in small-employment-sized rural communities, requiring analysis of the determinants of employment stability of these establishments. Aggregate SIC performance and most conventional criteria for judging probable stability appear to provide very limited predictability for individual firm performance. However, manufacturing development appears generally to have desirable effects on community-wide employment stability. 相似文献
472.
473.
Research has found that development exactions are capitalized into the price of new housing. As the price of new housing increases, one would expect to see a price rise in existing housing as well, albeit lagged to some extent. This paper presents the results of an empirical study designed to measure how much impact fees affect the price of existing, single-family dwellings. Data for this study were obtained from county property appraiser files provided by the Florida Department of Revenue. The data represent 1,055 new and 3,135 existing home sales, respectively, in Dunedin, Florida, and 7,292 existing home sales in Clearwater, Florida, from 1971-1982. On June 3, 1974, the city of Dunedin began assessing impact fees of $1,150 against all new, single-family construction. The methodology used in this paper examines the price differential of new relative to existing housing and finds that the difference disappeared after six years. 相似文献
474.
Experimental elimination of mast cells from the peritoneal tissues of the rat by distilled water treatment inhibited the increase of vascular permeability which normally follows a passively induced antigen-antibody reaction in peritoneal tissue. Thus mast cells may contribute to the initiation of inflammation which follows antigen-antibody reactions. 相似文献
475.
MITOMA C SMITH TE DACOSTA FM UDENFRIEND S PATCHETT AA WITKOP B 《Science (New York, N.Y.)》1959,129(3341):95-96
The administration of ketoproline to chick embryos resulted in an increase in the free hydroxyproline. This phenomenon is explained by the inhibitory action of ketoproline on the catabolism of hydroxyproline as well as by the conversion of the former to the latter. Ketoproline was found to be reduced to hydroxyproline by the supernatant fraction of rat-kidney homogenate in the presence of a reduced pyridine nucleotide. 相似文献
476.
<正>Soil organic matter (SOM), which associates carbon (C) to key plant nutrients, has been stored in soil for thousands of years. Scientists have long recognised its positive impact on key environmental functions such as food production and climate regulation. As soon as a virgin land (forest or grassland) is cultivated, there is a tendency for the soil to lose its SOM, and we still largely misunderstand the underlying mechanisms, leading to inappropriate decisions being taken to fight soi... 相似文献
477.
478.
Abstract. The bacterial flora of rainbow, Salmo gairdneri Richardson, and brown trout, Salmo trutta L., eggs was studied during incubation. Few bacteria were considered to exist internally, although Pseudomonas species and Aeromonas hydrophila were isolated. During incubation, large numbers of bacteria approaching 500 colony forming units/mm2 accumulated around egg surfaces. Both rainbow and brown trout eggs placed in a through-flow system were colonized mainly by Pseudomonas sp. and A. hydrophila , whilst rainbow trout eggs in a separate recycling system were dominated by a Cytophaga species. Glass beads were also incubated (as an inert surface) and found to support significantly lower numbers of bacteria. Egg mortalities were recorded daily and found to differ significantly between both fish species and water conditions. Statistical analysis indicated a potentially significant correlation between hatching success and numbers of surface bacteria. 相似文献