To elucidate the geomicrobiological factors controlling nitrification in salt marsh sediments, a comprehensive approach involving sediment geochemistry, process rate measurements, and quantification of the genetic potential for nitrification was applied to three contrasting salt marsh habitats: areas colonized by the tall (TS) or short (SS) form of Spartina alterniflora and unvegetated creek banks (CBs). Nitrification and denitrification potential rates were strongly correlated with one another and with macrofaunal burrow abundance, indicating that coupled nitrification-denitrification was enhanced by macrofaunal burrowing activity. Ammonia monooxygenase (amoA) gene copy numbers were used to estimate the ammonia-oxidizing bacterial population size (5.6 ؋ 10 4 to 1.3 ؋ 10 6 g of wet sediment ؊1 ), which correlated with nitrification potentials and was 1 order of magnitude higher for TS and CB than for SS. TS and CB sediments also had higher Fe(III) content, higher Fe(III)-to-total reduced sulfur ratios, higher Fe(III) reduction rates, and lower dissolved sulfides than SS sediments. Iron(III) content and reduction rates were positively correlated with nitrification and denitrification potential and amoA gene copy number. Laboratory slurry incubations supported field data, confirming that increased amounts of Fe(III) relieved sulfide inhibition of nitrification. We propose that macrofaunal burrowing and high concentrations of Fe(III) stimulate nitrifying bacterial populations, and thus may increase nitrogen removal through coupled nitrification-denitrification in salt marsh sediments.

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As one part of a larger progressive movement, the guidance and counseling movement has typically supported progressive programs in the schools and in society as a whole. While most counselors point with pride to such a progressive heritage, a case can be made that the effect of progressivism is to prop up existing structures and resist fundamental change in societal institutions. In this article the author discusses four ideals that are commonly held by the progressive and the counseling movements, pointing out some of the destructive effects these ideals have on societal change efforts. The four ideals discussed are: (a) an emphasis on access to opportunity (pluralism), (b) an emphasis on pragmatism, (c) an emphasis on adjustment, and (d) an emphasis on individualism.

Passage of the Omnibus Crime Control and Safe Streets Act of 1968 has led to both increased expenditure on police technology and humanistically oriented police training programs. While those two outcomes may seem contradictory, both aid police in their attempt to achieve social control. Advocates of humanistic police training programs have generally ignored the role of police in maintaining societal inequalities, repressing assent and social change, and diffusing legitimate protest. Seen in the light of those larger social issues, human relations skills in the hands of the police can become effective tools with which to achieve social control while avoiding the resistance generated by more coercive methods. As such, they function not as progressive, humanistic measures, but rather as a means for perpetuating human oppression.

In ErCIa at 4.2°K the ,oCI NQR frequencies are 4.4566±0.0002 and 4.5157±0.0002 MHz and the asymmetry parameters '1 are 0.53±0.02 and 0.S2±0.03 for the eightfold and fourfold sites, respectively. The electric field gradient xx principal axis at each site is within 4 0 of the bisector of the Er-CI-Er angle. The above results are analyzed in a "bond-switching" scheme. We report also the ,oCI NQR frequencies in the trichlorides of Y, Dy, Ho, Tm, Yb, La, and U. The adequacy of the point-change model as the primary source of the electric field gradient in these ionic crystals is tested.