ion and re-representation. COMPARING ANALOGIES AND MODELS The terms model and analog are often used interchangeably by both scientists and educators (Hesse, 1966, 2000; Duit, 1991). Comparing analogs and models based on the preceding review of the characteristics of each suggests that this interchangeability is valid when analogies are based on relational characteristics. The term "representati...

Lung function tests (forced expiratory volume in one second (FEV1), forced vital capacity (FVC) and FEV1/FVC %) were related to silica exposure and the extent of radiological opacities in a study of 206 active and 132 previously employed granite workers from two quarries. The investigations included detailed personal interviews, spirometric testing and radiographic examination of the chest. The...

Sea urchins are dominant members of rocky temperate reefs around the world. They often occur in cavities within the rock, and fit so tightly, it is natural to assume they sculpted these "pits." However, there are no experimental data demonstrating they bore pits. If they do, what are the rates and consequences of bioerosion to nearshore systems? We sampled purple sea urchins, Strongylocentrotus...

Indurated surficial veneers are a characteristic phenomenon on exposures of unjointed granite in the southeastern states. They are caused by deposition of iron oxides in the interstices between the partially disaggregated mineral grains of the "sap" rock at the surface of the exposure. Breaching of veneers produces such peculiar erosional forms as weather pits, cavernous boulders, and pedestal ...

Mard-abad calc-alkaline granite formed along the margin of active pull-apart or intra-continental plates, and it is post-collision granite type. Granophyric, perthitic and myrmekitic are main textures that could form from crystallization of hypersolvus source magma, which occurred under water vapor pressure of approximately 2 kb. During this study the temperature of formation of these granites ...