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Alpine, TX, United States

Sul Ross State University is a public university in Alpine, Texas, United States. Named for former Texas governor and Civil War general Lawrence Sullivan Ross, it was founded in 1917 as Sul Ross Normal College and was made a university in 1969.Sul Ross State University offers certificate programs and associate, bachelor's, and master's degrees. The main campus is situated in the unique environment of the Big Bend region and is the primary institution of higher education serving a 19-county area in far West Texas. SRSU has Rio Grande College branch campuses in Uvalde, Del Rio, and Eagle Pass.The university is governed by the Board of Regents of the Texas State University System, which guides seven universities in the state. Wikipedia.

The US Interior Department's Bureau of Ocean Energy Management, Regulation and Enforcement (BOEMRE) issued new requirements for oil and gas companies working on the US outer continental shelf to develop and implement a Safety and Environmental Management Systems (SEMS) program. The new regulation, which became effective November 15, 2011, incorporates and makes mandatory the American Petroleum Institute's Recommended Practice for Development of a Safety and Environmental Management Program for Offshore Operations and Facilities. The audit is the initial step in determining if an operator's SEMS program is effective. The company must develop a SEMS auditing program, which should define who is responsible for conducting the audit. All companies must define and document an emergency action plan and designate responsibilities for implementation of the plan. The first SEMS audit must be completed within two years of the initial implementation of the SEMS program. The audit scope should include a review of all company procedures addressing the SEMS elements. Source

Yue Y.,Oak Ridge National Laboratory | Yue Y.,Sul Ross State University | Fulvio P.F.,University of Puerto Rico at San Juan | Dai S.,Oak Ridge National Laboratory | Dai S.,University of Tennessee at Knoxville
Accounts of Chemical Research

ConspectusMetal-organic frameworks (MOFs) represent a new family of microporous materials; however, microporous-mesoporous hierarchical MOF materials have been less investigated because of the lack of simple, reliable methods to introduce mesopores to the crystalline microporous particles. State-of-the-art MOF hierarchical materials have been prepared by ligand extension methods or by using a template, resulting in intrinsic mesopores of longer ligands or replicated pores from template agents, respectively. However, mesoporous MOF materials obtained through ligand extension often collapse in the absence of guest molecules, which dramatically reduces the size of the pore aperture. Although the template-directed strategy allows for the preparation of hierarchical materials with larger mesopores, the latter requires a template removal step, which may result in the collapse of the implemented mesopores. Recently, a general template-free synthesis of hierarchical microporous crystalline frameworks, such as MOFs and Prussian blue analogues (PBAs), has been reported. This new method is based on the kinetically controlled precipitation (perturbation), with simultaneous condensation and redissolution of polymorphic nanocrystallites in the mother liquor. This method further eliminates the use of extended organic ligands and the micropores do not collapse upon removal of trapped guest solvent molecules, thus yielding hierarchical MOF materials with intriguing porosity in the gram scale. The hierarchical MOF materials prepared in this way exhibited exceptional properties when tested for the adsorption of large organic dyes over their corresponding microporous frameworks, due to the enhanced pore accessibility and electrolyte diffusion within the mesopores.As for PBAs, the pore size distribution of these materials can be tailored by changing the metals substituting Fe cations in the PB lattice. For these, the textural mesopores increased from approximately 10 nm for Cu analogue (mesoCuHCF), to 16 nm in Co substituted compound (mesoCoHCF), and to as large as 30 nm for the Ni derivative (mesoNiHCF). While bulk PB and analogues have a higher capacitance than hierarchical analogues for Na-batteries, the increased accessibility to the microporous channels of PBAs allow for faster intercalated ion exchange and diffusion than in bulk PBA crystals. Thus, hierarchical PBAs are promising candidates for electrodes in future electrochemical energy storage devices with faster charge-discharge rates than batteries, namely pseudocapacitors. Finally, this new synthetic method opens the possibility to prepare hierarchical materials having bimodal distribution of mesopores, and to tailor the structural properties of MOFs for different applications, including contrasting agents for MRI, and drug delivery. © 2015 American Chemical Society. Source

Backs J.R.,University of Illinois at Chicago | Terry M.,Sul Ross State University | Ashley M.V.,University of Illinois at Chicago
International Journal of Plant Sciences

Premise of research. Hybridization among oaks is well documented and is of special concern in conservation efforts directed toward threatened or endangered Quercus, species such as Quercus hinckleyi. Methodology. This study uses DNA microsatellite analysis to characterize hybridization between the threatened oak Q. hinckleyi C.H.Muller and two putative hybridizing species, Quercus pungens Liebmann and Quercus vaseyana Buckley. The two potential hybridizers were sampled at Guadalupe Mountains National Park (GUMO), approximately 320 km from the current range of Q. hinckleyi. Quercus pungens and two possible hybrids located in near proximity to the relict populations of Q. hinckleyi were also sampled. Pivotal results. Genetic variability was high in all three species, with mean number of alleles per locus ranging from 12.625 to 17.875, mean observed heterozygosity from 0.734 to 0.807, and mean expected heterozygosity from 0.851 to 0.869. Quercus hinckleyi is genetically differentiated from the putative hybridizers and has two distinct genetic clusters within its metapopulation. The two hybridizer species from GUMO, where they are sympatric, are not differentiated. The population identified as Q. pungens found near Q. hinckleyi is genetically distinct from the GUMO samples and has five of eight genets with greater than 90% Q. hinckleyi introgression. Two of the 14 identified Q. hinckleyi in close proximity to this population had Q. pungens introgression. Bayesian clustering analysis showed that 5% of the samples identified as Q. hinckleyi in the field were hybrids, and one putative hybrid was confirmed genetically. Conclusions. While there is some hybridization in the Q. hinckleyi population, we found no evidence of genetic swamping. This may be explained by the spatial isolation of the Q. hinckleyi remnants relative to other oak species and by its common asexual (cloning) method of reproduction. © 2015 by The University of Chicago. All rights reserved. Source

Platt S.G.,Wildlife Conservation Society | Thorbjarnarson J.B.,Wildlife Conservation Society | Rainwater T.R.,Medical University of South Carolina | Martin D.R.,Sul Ross State University
Journal of Herpetology

We studied diet and size-related dietary patterns among American Crocodiles (Crocodylus acutus) in marine habitats of coastal Belize (1996-1997). Prey items recovered from crocodile (N = 97) stomach contents included insects, mollusks, crustaceans, fish, amphibians, reptiles, birds, and mammals. Based on an overlapping group analysis of percent occurrence, we concluded that hatchlings and small juveniles feed largely on insects and crustaceans, larger juveniles broaden their diet to include fish and nonfish vertebrates, subadults consume increasing amounts of crustaceans with lesser amounts of insects and nonfish vertebrates, and adults subsist primarily on marine crustaceans. Dietary diversity was uniformly low across all size classes but greatest among small and large juveniles. Conversely, hatchlings, subadults, and adults had the most specialized (least diverse) diet owing to reliance upon a limited selection of prey, largely insects (hatchlings) or crustaceans (subadults and adults). Dietary overlap was greatest between adjacent size classes and lowest between the largest and smallest size classes. The high prevalence of freshly ingested prey among all size classes indicates frequent, regular feeding by C. acutus in coastal habitats, perhaps driven by the relatively small size of frequently consumed prey such as crabs. Because crabs have a blood salt content equivalent to the external medium and comprise a large portion of the diet, these prey likely impose a high osmoregulatory burden on C. acutus inhabiting hyperosmotic coastal environments. Contrary to earlier assertions that salt glands in C. acutus lack the excretory capacity to balance salt and water, we suggest populations in coastal Belize rely on these glands in addition to behavioral strategies to maintain osmotic homeostasis. Copyright 2013 Society for the Study of Amphibians and Reptiles. Source

Weckesser W.,102 Miguel Angel Court | Terry M.,Sul Ross State University
Journal of the Botanical Research Institute of Texas

Reed Plateau is a geographic feature in south Brewster County, Texas (U.S.A.) that exhibits a floral array characteristic of the northern Chihuahuan Desert region. Held as private property by many landowners, Reed Plateau and areas adjacent to it have never been the focus of a botanical study. A survey of Reed Plateau and adjacent areas was conducted from August 2004 through November 2007, with a total of 1065 specimens collected. The flora consists of 262 taxa, including 1 subspecies and 15 varieties, in 188 genera and 63 families. The best-represented families are the Asteraceae (33 species), Poaceae (23 species), Fabaceae (18 species), Cactaceae (17 species), and Euphorbiaceae (13 species). One federally listed threatened species, Echinomastus mariposensis, was identified within the study area. The only known U.S. populations of Genistidium dumosum occur on Reed Plateau. The occurrence of Stemodia coahuilensis represents a new county record, and a new Hibiscus hybrid was described. Two Big Bend and three Trans-Pecos endemics were documented. Four non-native species were collected, three of which are considered noxious or invasive. The vegetation associations found in the Reed Plateau study area strongly reflect the predominantly limestone substrate of the Terlingua-Solitario structural block. Diverse geographic factors within the relatively small study area support floral diversity patterns which are compared to studies from nearby Big Bend National Park and Big Bend Ranch State Park, as well as the Southwestern United States and the Chihuahuan Desert region. Source

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