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Grand Junction, CO, United States

Colorado Mesa University , formerly known as Mesa State College, is a public comprehensive university in Grand Junction, Colorado. The university has its primary campus in central Grand Junction. The university also has other campuses as well; Bishop Campus, which houses Western Colorado Community College in northwestern Grand Junction and a regional campus in Montrose, Colorado. Colorado Mesa University grants two-year associate degrees, four-year bachelor's degrees, and master's degrees.Previously called Mesa State College , the school attained university status in August 2011, changing its name to Colorado Mesa University. Wikipedia.

Lazear G.,20508 Brimstone Road | Karlstrom K.,University of New Mexico | Aslan A.,Colorado Mesa University | Kelley S.,New Mexico Institute of Mining and Technology
Geosphere | Year: 2013

Over the past 10 Ma, the high-relief landscapes of the Colorado Plateau-southern Rocky Mountains region have been shaped by erosional processes. Incision rates have increased in the southern Rocky Mountains, the Colorado River system has been superimposed across buried Laramide structures as it was integrated from the Rocky Mountains to the Gulf of California, the modern Grand Canyon formed, and there has been widespread denudation of the Canyonlands region of the Colorado Plateau. We examine the spatial and temporal distribution of erosion and its associated isostatic rebound since 10 Ma. Erosion estimates come from apatite fi ssion track (AFT) and apatite (U-Th)/He (AHe) thermochronometric studies at 14 sites across the region, including recent AHe data with ages younger than 12 Ma, and from ca. 10 Ma40Ar/39Ar dated basalt paleosurfaces at 55 locations on the perimeter of the Colorado Plateau and in the southern Rocky Mountains. Estimated eroded thickness is added to modern topography above numerous control points to reconstruct a 10 Ma paleosurface across the region (referenced to modern elevations); this also yields an eroded thickness volume. Erosion has been spatially variable since 10 Ma: we fi nd widespread denudation with as much as 2 km of incision along rivers in the Canyonlands region of Utah, 1-1.5 km of incision along rivers exiting the Rocky Mountains onto the eastern piedmont since 6 Ma, ~1 km removed across the high peaks of the southern Rocky Mountains since 10 Ma, and little net erosion in the Basin and Range. Post-10 Ma flexural isostatic response to the eroded volume is calculated using known variable elastic thickness. This rebound caused much of the Colorado Plateau region to undergo more than 800 m of rock uplift, exceeding 1 km in local areas in the Canyonlands and southwestern Colorado. The Lees Ferry andGlen Canyon areas have been isostatically uplifted >500 m relative to the eastern Grand Canyon and the Tavaputs Plateau has been isostatically uplifted 400 m relative to Browns Park. This differential rock uplift driven by erosional isostasy has created or accentuated many of the features of the modern landscape. This component of rock uplift is "removed" by adding the eroded thickness onto modern topography, then subtracting the calculated rebound. The resulting (preerosion and pre-rebound) map provides a model of the 10 Ma landscape, neglecting any tectonic uplift contribution to regional elevations. This model suggests the presence of internal drainages on the Colorado Plateau, that the elevation of the Green River Basin and the Tavaputs Plateau were subequivalent, allowing the Green River to flow southward, and shows high topography in the Rocky Mountains that mimicked modern topography, but with potentially lower relief. Future refi nements of both the timingand magnitude of differential erosion and rebound models provide an avenue for improved models for Cenozoic landscape evolution of the region. This paper is an advance over previous studies that focused just on the Colorado Plateau. Here we evaluate isostatic response to erosion in an extended region that includes parts of the Basin and Range, Colorado Plateau, southern Rocky Mountains, and eastern piedmont of the Rocky Mountains. We fi nd that erosion of the southern Rocky Mountains and eastern piedmont is compara ble to that of the Colorado Plateau and that the flexural isostatic rebounds of all these regions arecoupled and cannot be considered in isolation. Furthermore, we focus on the 10 Ma time frame, rather than the 30 or 70 Ma period of previous researchers, as the key time frame during which the modern landscape rapidly evolved. In addition, the use of AFT and AHe thermochronometric constraints on thicknesses and ages of noweroded sediments has solved key problems that hampered previous erosion studies. Data and analyses of regional post-10 Madifferential erosion and its resulting differential isostatic rebound provide essential constraints for any viable models for landscape evolution in this classic region. © 2013 Geological Society of America. Source

Hampton P.M.,University of Louisiana at Lafayette | Hampton P.M.,Colorado Mesa University
Journal of Zoology | Year: 2013

The diversity of feeding mechanisms among predators reflects phenotypic modifications that may improve feeding performance on a preferred prey type. I compared trophic morphology, feeding performance (time and upper-jaw walks) and behavior (initial bite and ingestion directions) among three species of natricine snakes that were fed fish and frogs over a broad range of relative prey sizes. Feeding behavior was influenced by prey type but did not differ among the snake species. Both bite and ingestion directions influenced the number of upper-jaw movements (lateral excursions and protractions) required to consume fish, but only initial bite position significantly affected the number of upper-jaw movements required to ingest frogs. Within snake species, feeding performance did not differ between fish and frogs for Nerodia fasciata and Nerodia rhombifer; however, Thamnophis proximus consumed fish with fewer upper-jaw movements. Feeding time differed significantly among snake species when fed both fish and frogs. Trophic morphology did not significantly affect ingestion costs for fish but did influence ingestion when fed frogs. In general, differences in trophic morphology among the three species are not correlated to handling and ingestion performance. © 2013 The Zoological Society of London. Source

Snyder J.,Colorado Mesa University
Reference and User Services Quarterly | Year: 2013

Mention Wikipedia in a group of people and a lively discussion is sure to follow with terms such as peer-review, editing policies, and Web 2.0 entering the conversation. Wikipedia is the open access, Web 2.0 encyclopedia that is harnessing the power (and knowledge) of the masses and making it freely available to the Internet audience. With open access, problems have appeared and solutions have been implemented; however, many netizens (network citizens) are only aware of the negative and high profile misuses of Wikipedia, skewing their view of this knowledge repository. This paper studies how one group of information seekers, librarians, is utilizing this freely accessible web resource in their work, and how positive and negative awareness affects this usage. Usage statistics, awareness statistics, and gender differences for Wikipedia usage are presented in this paper and discussed. Comparisons of librarian statistics to previously published data on university faculty and student usage of Wikipedia are presented. It is established that librarians have greater awareness of negative issues surrounding Wikipedia than of positive issues. This awareness drives usage of Wikipedia in personal and professional settings. Results also indicate that there are no major gender differences in awareness of positive and negative issues concerning Wikipedia, but that males tend to use Wikipedia more than females, confirming the results of previous studies. © 2013 American Library Association. All rights reserved. Source

Middleton C.A.,Colorado Mesa University
American Journal of Physics | Year: 2015

Embedding diagrams prove to be quite useful when learning general relativity as they offer a way of visualizing spacetime curvature through warped two dimensional (2D) surfaces. In this manuscript, we present a different 2D construct that also serves as a useful conceptual tool for gaining insight into gravitation: orbital dynamics-namely, the cylindrically symmetric surfaces that generate Newtonian and general relativistic orbits with small eccentricities. Although we first show that no such surface exists that can exactly reproduce the arbitrary bound orbits of Newtonian gravitation or of general relativity (or, more generally, of any spherically symmetric potential), surfaces do exist that closely approximate the resulting orbital motion for small eccentricities (exactly the regime that describes the motion of the solar system planets). These surfaces help to illustrate the similarities and differences between the two theories of gravitation (i.e., stationary elliptical orbits in Newtonian gravitation and precessing elliptical-like orbits in general relativity) and offer, in this age of 3D printing, an opportunity for students and instructors to experimentally explore the predictions made by each. © 2015 American Association of Physics Teachers. Source

Weinberg D.R.,University of North Carolina at Chapel Hill | Weinberg D.R.,Colorado Mesa University | Gagliardi C.J.,University of North Carolina at Chapel Hill | Hull J.F.,University of North Carolina at Chapel Hill | And 7 more authors.
Chemical Reviews | Year: 2012

Proton-coupled electron transfer (PCET) has a major role in chemistry and biology and its implications for catalysis and energy conversion. Photosynthesis is a spectacular example of PCET in action with the transfer of 24 e- and 24 H+ driven by at least 48 photons. In PCET half reactions, variations in pH influence driving force. Both HAT (H-atom transfer) and EPT (electron-proton transfer) are elementary steps by which PCET reactions can occur. In H-atom transfer (HAT), both the transferring electron and proton come from the same bond in one of the reactants. Multiple Site Electron-Proton Transfer (MS-EPT) is microscopically more complex than electron or proton transfer. It shares with electron transfer requirements for medium and intramolecular reorganization but with the additional complexity of a coupled proton transfer. PCET plays a critical role in many enzymatic pathways that control life such as photosynthesis, respiration, and DNA repair. Source

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