Entity

Time filter

Source Type

Logan, UT, United States

Utah State University is a public research university in Logan, Utah. Founded in 1888 as Utah's agricultural college, USU focused on agriculture, domestic arts, and mechanic arts. The university now offers programs in liberal arts, engineering, business, economics, natural resource science, as well as nationally ranked elementary & secondary education programs. The university has eight colleges and offers a total of 176 bachelor's degrees, 97 master's degrees, and 38 doctoral degrees. It is a land-grant and space-grant institution accredited by the Northwest Commission on Colleges and Universities.USU's main campus is located in Logan with regional campuses in Brigham City, Tooele, and the Uintah Basin. In 2010, the College of Eastern Utah, located in Price, Utah joined the USU system becoming Utah State University College of Eastern Utah . Throughout Utah, USU operates more than 20 distance education centers. Regional campuses, USU Eastern, and distance education centers provide degrees to more than 40% of the students enrolled. In total, USU has more than 180,000 alumni in all 50 states and more than 100 countries.With more than 16,000 students living on or near campus, USU is the largest public residential campus in Utah.USU's athletic teams compete in Division I of the NCAA and are collectively known as the Utah State Aggies. They are members of the Mountain West Conference. Wikipedia.


Fejer B.G.,Utah State University
Space Science Reviews | Year: 2011

The low latitude ionosphere is strongly affected by several highly variable electrodynamic processes. Over the last two decades ground-based and satellite measurements and global numerical models have been extensively used to study the longitude-dependent climatology of low latitude electric fields and currents. These electrodynamic processes and their ionospheric effects exhibit large ranges of temporal and spatial variations during both geomagnetic quiet and disturbed conditions. Numerous recent studies have investigated the short term response of equatorial electric fields and currents to lower atmospheric transport processes and solar wind-magnetosphere driving mechanisms. This includes the large electric field and current perturbations associated with arctic sudden stratospheric warming events during geomagnetic quiet times and highly variable storm time prompt penetration and ionospheric disturbance dynamo effects. In this review, we initially describe recent experimental and numerical modeling results of the global climatology and short term variability of quiet time low latitude electrodynamic plasma drifts. Then, we examine the present understanding of equatorial electric field and current perturbation fields during periods of enhanced geomagnetic activity. © Springer Science+Business Media B.V. 2011.


Sinsabaugh R.L.,University of New Mexico | Shah J.J.F.,Utah State University
Annual Review of Ecology, Evolution, and Systematics | Year: 2012

The net primary production of the biosphere is consumed largely by microorganisms, whose metabolism creates the trophic base for detrital foodwebs, drives element cycles, and mediates atmospheric composition. Biogeochemical constraints on microbial catabolism, relative to primary production, create reserves of detrital organic carbon in soils and sediments that exceed the carbon content of the atmosphere and biomass. The production of organic matter is an intracellular process that generates thousands of compounds from a small number of precursors drawn from intermediary metabolism. Osmotrophs generate growth substrates from the products of biosynthesis and diagenesis by enzyme-catalyzed reactions that occur largely outside cells. These enzymes, which we define as ecoenzymes, enter the environment by secretion and lysis. Enzyme expression is regulated by environmental signals, but once released from the cell, ecoenzymatic activity is determined by environmental interactions, represented as a kinetic cascade, that lead to multiphasic kinetics and large spatiotemporal variation. At the ecosystem level, these interactions can be viewed as an energy landscape that directs the availability and flow of resources. Ecoenzymatic activity and microbial metabolism are integrated on the basis of resource demand relative to environmental availability. Macroecological studies show that the most widely measured ecoenzymatic activities have a similar stoichiometry for all microbial communities. Ecoenzymatic stoichiometry connects the elemental stoichiometry of microbial biomass and detrital organic matter to microbial nutrient assimilation and growth. We present a model that combines the kinetics of enzyme activity and community growth under conditions of multiple resource limitation with elements of metabolic and ecological stoichiometry theory. This biogeochemical equilibrium model provides a framework for comparative studies of microbial community metabolism, the principal driver of biogeochemical cycles. © 2012 by Annual Reviews. All rights reserved.


It is well known that noncovalent bonds are weakened when stretched from their equilibrium intermolecular separation. Quantum chemical calculations are used to examine and compare the sensitivity to stretches of hydrogen, halogen, chalcogen, and pnicogen bonds. NH3 was taken as the universal electron donor, paired with HOH and FH in H-bonds, as well as with FPH 2, FSH, and FCl. Even though the binding energies span a wide range, stretching the intermolecular separation by 1 Å cuts this quantity by the same proportion, roughly in half, for each system. Taking the sum of van der Waals radii as an arbitrary cutoff, the H-bond energy in FH⋯NH 3 remains at 5.5 kcal mol-1 while the binding energy of the other three bond types is only slightly smaller at 4.5-4.7 kcal mol -1. © 2013 The Royal Society of Chemistry.


Gompert Z.,Utah State University
Molecular Ecology | Year: 2016

Evolutionary geneticists have sought to characterize the causes and molecular targets of selection in natural populations for many years. Although this research programme has been somewhat successful, most statistical methods employed were designed to detect consistent, weak to moderate selection. In contrast, phenotypic studies in nature show that selection varies in time and that individual bouts of selection can be strong. Measurements of the genomic consequences of such fluctuating selection could help test and refine hypotheses concerning the causes of ecological specialization and the maintenance of genetic variation in populations. Herein, I proposed a Bayesian nonhomogeneous hidden Markov model to estimate effective population sizes and quantify variable selection in heterogeneous environments from genetic time-series data. The model is described and then evaluated using a series of simulated data, including cases where selection occurs on a trait with a simple or polygenic molecular basis. The proposed method accurately distinguished neutral loci from non-neutral loci under strong selection, but not from those under weak selection. Selection coefficients were accurately estimated when selection was constant or when the fitness values of genotypes varied linearly with the environment, but these estimates were less accurate when fitness was polygenic or the relationship between the environment and the fitness of genotypes was nonlinear. Past studies of temporal evolutionary dynamics in laboratory populations have been remarkably successful. The proposed method makes similar analyses of genetic time-series data from natural populations more feasible and thereby could help answer fundamental questions about the causes and consequences of evolution in the wild. © 2015 John Wiley & Sons Ltd.


Scheiner S.,Utah State University
International Journal of Quantum Chemistry | Year: 2013

The characteristics of the pnicogen bond are explored using a variety of quantum chemical techniques. In particular, this interaction is compared with its halogen and chalcogen bond cousins, as well as with the more common H-bond. In general, these bonds are all of comparable strength. More specifically, they are strengthened by the presence of an electronegative substituent on the electron-acceptor atom, and each gains strength as one moves down the appropriate column of the periodic table, for example, from N to P to As. These noncovalent bonds owe their stability to a mixture in nearly equal parts of electrostatic attraction and charge transfer, along with a smaller dispersion component. The charge transfer arises from the overlap between the lone pair of the electron donor and a σ* antibond of the acceptor. The angular characteristics of the equilibrium geometry result primarily from a compromise between electrostatic and induction forces. Angular distortions of the H-bond are typically less energetically demanding than comparable bends of the other noncovalent bonds. © 2012 Wiley Periodicals, Inc.

Discover hidden collaborations