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Concern over accelerated eutrophication in many agricultural watersheds has focused attention on novel management practices to reduce phosphorus (P) transfers from agricultural fields to downstream surface waters (Sims et al. [...]

Artificial or improved drainage is used to increase agricultural production on many soils, representing as many as 40 million ha (100 million ac) throughout the United States (Pavelis 1987). Poor [...]

Drainage ditch networks are ubiquitous in the poultry-producing region of the Delmarva Peninsula due to the flat coastal plain landscape and predominance of poorly drained soils requiring artificial drainage to [...]

Nitrogen (N) and phosphorus (P) are the primary nutrients that accelerate eutrophication in fresh surface waters (Carpenter et al. 1998). Eutrophication is an aging process where influxes of nutrients promote [...]

Artificial drainage and ditching are essential for crop production in many areas of the United States, either for direct land drainage or as conduits for tile drain and irrigation effluent. [...]

Cu-paddle-wheel-based Cu3(BTC)2 (nicknamed Cu-BTC, where BTC ≡ benzene 1,3,5-tricarboxylate) is a metal organic framework (MOF) compound that adopts a zeolite-like topology. We have determined the pore-size distribution using the Gelb and Gubbins technique, the microstructure using small-angle neutron scattering and (ultra) small-angle X-ray scattering (USAXS\SAXS) techniques, and X-ray powder diffraction reference patterns for both dehydrated d-Cu-BTC [Cu3(C9H3O6)2] and hydrated h-Cu-BTC [Cu3(C9H3O6)2(H2O)6.96] using the Rietveld refinement technique. Both samples were confirmed to be cubic Fm$\bar 3$m (no. 225), with lattice parameters of a = 26.279 19(3) Å, V = 18 148.31(6) Å3 for d-Cu-BTC, and a = 26.3103(11) Å, and V = 18 213(2) Å3 for h-Cu-BTC. The structure of d-Cu-BTC contains three main pores of which the diameters are approximately, in decreasing order, 12.6, 10.6, and 5.0 Å. The free volume for d-Cu-BTC is approximately (71.85 ± 0.05)% of the total volume and is reduced to approximately (61.33 ± 0.03)% for the h-Cu-BTC structure. The d-Cu-BTC phase undergoes microstructural changes when exposed to moisture in air. The reference X-ray powder patterns for these two materials have been determined for inclusion in the Powder Diffraction File. [ABSTRACT FROM AUTHOR]

Silicone tubing was used to divert aqueous humor from the anterior chamber of the right eye to the rostral compartment of the right frontal sinus in four clinically normal mixed-breed dogs. Biomicroscopic examination, and pneumoapplanation tonometry and tonography, completed for up to 18 weeks postoperatively, confirmed gonioimplant function in all four cases. The dogs were euthanized at 6, 8, 16 and 18 weeks postoperatively. Gonioimplant patency was further confirmed by postmortem examination of the globes, implants and frontal sinuses. Gross and light microscopic examinations revealed iridal attachments to the implant (n = 4), mild anterior uveitis (n = 3), anterior subcapsular cataracts (n = 4), and focal corneal (n = 3) and scleral (n = 3) scarring in the operated globes. Light microscopic examination of frontal sinus specimens revealed mild lymphocytic proliferation and fibrosis immediately adjacent to the implant entrance site. There were no bacteria detected on aerobic or anaerobic cultures of the frontal sinuses or light microscopic examination of the globes or frontal sinuses. Results indicate that the frontal sinus shunting of aqueous humor is a safe and effective means of extraorbital aqueous diversion with potential applicability in the management of glaucoma.