University of Rhode Island

About: University of Rhode Island is a education organization based out in Kingston, Rhode Island, United States. It is known for research contribution in the topics: Population & Bay. The organization has 11464 authors who have published 22770 publications receiving 841066 citations. The organization is also known as: URI & Rhode Island College of Agriculture and the Mechanic Arts.

Hotspot-migrating ridge interaction in the South Atlantic

Abstract: Short-wavelength geochemical anomalies in the basaltic layer 2A occur along the South Atlantic mid-ocean ridge opposite Ascension, St Helena and Tristan hotspots, further evidence that preferential subcrustal flow channels develop between mantle upwelling zones (hotspots) and migrating ridge axes. Geochemical variability suggests that the plume along these channels would be schlieren-like rather than continuous.

Nitrogen transport by vertically migrating diatom mats in the North Pacific Ocean

Abstract: PHYTOPLANKTON production in the surface waters of stratified oceans is fed mainly by nitrogen that has been recycled within the euphotic zone1. The nitrogen that is lost from surface waters as organic matter exported to the deep ocean must be balanced by inputs of new nitrogen to the upper ocean2,3. Sediment trap studies2 have shown that the 15N/14N ratio (δ15N) of the exported organic matter is higher than that of the suspended particulates, and suggest that the rich nitrate pool below the euphotic zone is the source of 'new' nitrogen for the upper ocean. Yet steep vertical concentration gradients suggest that diffusive upward transport of nitrate is extremely limited, raising the question of how the nitrate reaches the surface waters. Here we present evidence that abundant diatom (Rhizosolenia) mats migrate vertically between surface waters and deep nitrate pools in the central North Pacific Ocean. Rising mats contain significantly larger internal nitrate pools than sinking mats. Mat δ15N is similar to that of the sub-nitricline nitrate, and consistently heavier than that of near-surface particulate organic matter. We conclude that Rhizosolenia mats may transport the equivalent of 50% of the new nitrogen requirements into the surface waters of the North Pacific gyre.

Optical Phonons of Yttrium Aluminum Garnet

Abstract: The dielectric properties and optical phonons of yttrium aluminum garnet (YAG) have been studied by measurements of the infrared (IR) reflection spectra and the Raman effect. A factor group analysis of the YAG space group shows that there are $18 {T}_{1u}$ IR-active modes, and $3 {A}_{1g}$, $8 {E}_{g}$, and $14 {T}_{2g}$ Raman-active modes. The IR data have been interpreted by a Kramers-Kronig transform to yield values of the complex dielectric constant and frequencies of the longitudinal and transverse long-wavelength ${T}_{1u}$ modes. 15 of the 17 predicted ${T}_{1u}$ optic modes have been observed. All the ${A}_{1g}$ and ${E}_{g}$ modes have been identified, but at least 3 of the $14 {T}_{2g}$ modes are missing from the observed Raman spectra.

Citizen Participation and Community Organizations

Abstract: The noted black educator Benjamin Mays said: “nobody is wise enough, nobody is good enough, and nobody cares enough about you, for you to turn over to them your future or your destiny.” Citizen participation creates the potential for schools, neighborhoods, and other institutions, environments, and services responsive to individuals and families. Citizen participation is defined as “a process in which individuals take part in decision making in the institutions, programs, and environments that affect them” (Heller, Price, Reinharz, Riger, & Wandersman, 1984, p. 339; see Churchman, 1987, for definitions of participation in different disciplines)