We commend Wendy Levinson for her provocative suggestions regarding revalidation of Canadian physicians. We also applaud CMAJ for publishing views that are more demanding and supportive of meaningful external verification of Canadian physicians’ ongoing competence than those of the Canadian Medical Association. We agree with much of what Levinson has advocated, specifically the call for a reval...

the alginate was extracted with six different methods from iran south seacoast algae, sargassum sp, and the percentage yield of alginate was determined. we divided our methods to two groups including acidic extraction and non-acidic. in acidic methods, hcl and h 2 so 4 were used as a detergent in extraction process and cacl 2 was exerted in non-acidic treatments. all treatments compared with ea...

We use theory and empirics to examine the effect of environmental regulations on trade flows. A simple model demonstrates how unobserved heterogeneity, endogeneity, and aggregation issues bias standard measurements of this relationship. A reduced-form estimate of the model, using data on U.S. regulations and trade with Canada and Mexico for 130 manufacturing industries from 1977 to 1986, indica...

This work focuses on the concept of frame of reference. Levinson (2003) suggested that spatial information encoded in one frame of reference cannot be translated into another one. While this is partially true in language, I argue for a nesting relationship between frames of reference at the conceptual level. A set of spatial concepts suggested by Lehman & Bennardo (2003) informs this investigat...

D. M. Levinson, Institute of Transportation Studies, University of California at Berkeley, Berkeley, Calif. 94720. Y. Huang, Transportation Planning Division, Maryland National Capital Park and Planning Commission, 8787 Georgia Avenue, Silver Spring, Md. 20910. A transportation planning model that integrates regional and local-area forecasting approaches is developed and applied. Although regio...

sulfated polysaccharides have shown promising effects on wound healing processes along with many other biological activities. the sulfated polysaccharides extracted from two algae species habitats in persian gulf were studied in vivo for their effects on collagen formation and epidermal regeneration. the polysaccharides were purified from aqueous extracts of p. tetrastromatica and p. boergeseni...

Understatement might not seem like a big deal, but it is a force to be reckoned with. The phenomenon is paradoxical on the face of it: minus dicimus, plus significamus, say less and mean more. An understatement is a statement which, somehow, because it is conspicuously less informative than some other statement, can be used to express the meaning of the more informative statement. It is not a p...