Biogeochemical silica mass balances in Lake Michigan and Lake Superior

Silica budgets for Lake Michigan and Lake Superior differ in several respects. Mass balance calculations for both lakes agree with previous studies in that permanent burial of biogenic silica in sediments may be only about 5% of the biogenic silica produced by diatoms. Because dissolution rates are large, good estimates of permanent burial of diatoms can not be obtained indirectly from the internal cycle of silica (silica uptake by diatoms and subsequent dissolution) but must be obtained from the sediment stratigraphy. The annual net production of biogenic silica in Lake Michigan requires 71% of the winter maximum silica reservoir which must be maintained primarily by internal cycling in this large lake whereas the comparable silica demand in Lake Superior is only 8.3%. The greater silica demand in Lake Michigan is the result of phosphorus enrichment which has increased diatom production. It is hypothesized that steady-state silica dynamics in Lake Michigan were disrupted by increased diatom production between 1955 and 1970 and that a new steady state based on silica-limited diatom production developed after 1970. Mass balance calculations for Lake Michigan show in contrast with previous work that the hypothesized water column silica depletion of 3.0 g · m −3 could have occurred even though 90% or more of the biogenic silica production is recycled.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42471/1/10533_2004_Article_BF02187199.pd

The Christian-Muslim Consultative Group: a Model of Dialogue for the Common Good

The Christian-Muslim Consultative Group of Southern California was founded in 2006 to “work in partnership with leaders of various streams of Southern California Christian and Muslim communities to enhance mutual understanding, respect, appreciation, and support of the Sacred in each other.” In this panel, the two convenors of the group discussed the programmatic and educational elements of their work. Theme of the day: identities. the multiple faces of convivencia “Protestant, Catholic and Jew” no longer works to describe either us or the US. Whose voices get heard at the table? Can I be Muslim and American? Or do I have to choose? Whose religion/ethnicity/sexuality/class/politics = US

Studies of Knock-Out Reactions: 40-Ca(p,2p)39-K Revisited

This work was supported by the National Science Foundation Grant NSF PHY 81-14339 and by Indiana Universit

Religious Education in Los Angeles

In what is both the largest Catholic archdiocese in the USA and the most religiously diverse city in the world, what are the issues that arise for religious education? Theme of the day: religion.life.LA. We live in the most religiously diverse city in the world. What do we –and what don’t we—share? In the city where America imagines itself and the world, how much room is there for God? for you? for me? In LA, does U+I = US