Publications

Garnet has been used as a gemstone since the Bronze Age. However, garnet's angular fractures, relatively high hardness and specific gravity, chemical inertness, and nontoxicity make it ideal for many industrial applications. It is also free of crystalline silica and can be recycled.

Fifteen companies mined kaolin in nine states in 2011. Production, on the basis of preliminary data, was estimated to be 5.48 Mt (6.04 million st) valued at $822 million, an increase from 5.42 Mt (5.97 million st) valued at $788 million in 2010. Production in Georgia, the top producing state, increased to an estimated 5.1 Mt (5.62 million st) valued at $790 million in 2011 from 5.05 Mt...

The United States is import-reliant for nearly all of the bauxite that it consumes. Small amounts of bauxite and bauxitic clays are produced in Alabama, Arkansas and Georgia for nonmetallurgical uses. Metallurgical-grade bauxite (crude dry) imports in 2011 totaled 9.54 Mt (10.5 million st), 18 percent more than the quantity imported in 2010. Jamaica (54 percent). Guinea (25 percent) and...

In the central Appalachians, carbonate deposition of the great American carbonate bank began during the Early Cambrian with the creation of initial ramp facies of the Vintage Formation and lower members of the Tomstown Formation. Vertical stacking of bioturbated subtidal ramp deposits (Bolivar Heights Member) and dolomitized microbial boundtsone (Fort Duncan Member) preceded the...

We identify step-changes in the physical, chemical and biological characteristics of the Gulf of Maine (GoM) using the Gulf of Maine North Atlantic Time Series (GNATS), a series of oceanographic measurements obtained between September 1998 and December 2010 along a transect in the GoM running from Portland, ME, to Yarmouth, NS. GNATS sampled a period of extremes in precipitation and...

Exposure of Atlantic salmon smolts to estrogenic compounds is shown to compromise several aspects of smolt development. We sought to determine the underlying endocrine mechanisms of estrogen impacts on the growth hormone (GH)/insulin-like growth factor I (IGF-I) axis. Smolts in freshwater (FW) were either injected 3 times over 10 days with 2 μg g−1 17β-estradiol (E2) or 150 μg g−1 4...

Teleost fishes are able to acclimatize to seawater by secreting excess NaCl by means of specialized “ionocytes” in the gill epithelium. Antibodies against Na+/K+-ATPase (NKA) have been used since 1996 as a marker for identifying branchial ionocytes. Immunohistochemistry of NKA by itself and in combination with Na+/K+/2Cl− cotransporter and CFTR Cl− channel provided convincing evidence...

Based on conventional mass transfer models developed for oxygen, the use of the non-linear ASCE method, 2-point method, and one parameter linear-regression method were evaluated for carbon dioxide stripping data. For values of K L aCO2 approximately 1.5/h, the 2-point or ASCE method are a good fit to experimental data, but the fit breaks down at higher values of K L aCO2. How to correct...

Shortnose sturgeon Acipenser brevirostrum is an endangered polyploid fish species for which no nuclear DNA markers previously existed. To address this need, 86 polysomic loci were developed and characterized in 20 A. brevirostrum from five river systems and eight members (parents and six progeny) of a captive-bred family. All markers proved to be polymorphic, polysomic, and demonstrated...

Among numerous anthropogenic impacts on terrestrial landscapes, expanding transportation networks represent one of the primary challenges to wildlife conservation worldwide. Larger mammals may be particularly vulnerable because of typically low densities, low reproductive rates, and extensive movements. Although numerous studies have been conducted to document impacts of road networks on...

Two previously undescribed species of myxozoan parasites were observed in the gills of bass inhabiting the Potomac and James River basins. They are described using morphological characteristics and small-subunit (SSU) rDNA gene sequences. Both were taxonomically identified as new species of Myxobolus; Myxobolus branchiarum n. sp. was found exclusively in smallmouth bass, and Myxobolus...

Nature-like fishways have been designed with the intent to reconnect river corridors and provide passage for all species occurring in a system. The approach is gaining popularity both in Europe and North America, but performance of these designs has not been quantitatively evaluated in a field setting for any North American species. Two nature-like fishways and three technical fishways...