This article presents a historical review of mathematics education since the late 1950s in the United States. Three themes are used to organize the literature reviewed in the article: (a) broad sociopolitical forces, particularly highly publicized educational policy statements; (b) trends in mathematics research; and (c) theories of learning and instruction. At times, these themes coincide, as ...

We analyzed botanical, geologic, and climatic data in an effort to understand why there are many more serpentine endemics—i.e., plant species restricted to ultramafic substrates—in some regions of California than in others. We found that, in addition to elevational range (which subsumed the effect of serpentine area) and annual rainfall, the age of exposure of serpentine explained significant g...

Compositional variations of talc in peridotites and serpentinites could have significant implications for modeling geochemical cycles involving the upper mantle but been scarcely studied. We analyzed chemical compositions prograde retrograde associated minerals thermally metamorphosed from Southwest Japan. The has Si, Al, Mg, Fe, Na contents. Most Fe indicate mechanical mixing with serpentine c...

Serpentine cord formation in BACTEC 12B medium was evaluated as a rapid method for the presumptive identification of M. tuberculosis complex. Kinyoun acid-fast stained smears were prepared from 666 positive BACTEC 12B bottles and examined for the presence or absence of serpentine cording. Cord formation had a sensitivity, specificity, positive predictive value, and negative predictive value of ...

Nickel hyperaccumulator plants contain at least 1,000 mg Ni/g dry mass. Their high-Ni tissues present a chemically unique resource for herbivorous insects. A prior survey of insects associated with the Ni hyperaccumulator Streptanthus polygaloides in California yielded a new species, Melanotrichus boydi Schwartz and Wall (Hemiptera: Miridae). Here we document the host preference of M. boydi. Su...

A phytosociological review is carried out of the pine forest formations on islands Cuba and Hispaniola (Caribbean), due to diversity soils environments. We collected 10 plant associations belonging class Byrsonimo-Pinetea caribaea growing siliceous, calcareous sandy substrates 21 special, serpentine ophite ultramafic rocks Caseario crassinervis-Pinetea cubensis, exclusive Cuba; while associatio...

We investigated accumulation of elements (Ca, Co, Cr, Cu, Fe, K, Mg, Mn, P, Pb, and Zn) in leaves of different ages for 11 evergreen woody plant species from serpentine soils of New Caledonia. Species were classifi ed into four categories of Ni accumulation ability: one species was a non-accumulator (<100 mg Ni/ kg), three were accumulators (100–1000 mg Ni/kg), two were hyperaccumulators (1000–...