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Yuma, AZ, United States

Arizona Western College is a public community college located in Yuma, Arizona, United States. AWC offers classes in San Luis, Somerton, Yuma, Wellton, Dateland, and La Paz.The school's sports teams are called the Matadors and the school colors are cardinal and gold. They participate in the NJCAA, the ACCAC, and the WSFL. Wikipedia.

Hogan F.,University of Massachusetts Dartmouth | Cadrin S.,University of Massachusetts Dartmouth | Haygood A.,Arizona Western College
North American Journal of Fisheries Management | Year: 2013

There are seven species of skates (family Rajidae) found along the East Coast of the USA. All seven species are currently managed by the New England Fisheries Management Council as a single management complex extending from the Gulf of Maine to Cape Hatteras. The objective of the management plan is to ensure the long-term sustainability of fishing for each species via a trip limit approach. Two species are harvested in two distinct commercial fisheries. Northeast Fisheries Science Center trawl survey data and published literature were examined to investigate differences between the individual species in the skate complex. Each species exhibited a unique thermal and geographic range in addition to vital life history traits (e.g., age at maturity, longevity, and maximum size). Thorny Skate Amblyraja radiata and Smooth Skate Malacoraja senta have narrow thermal ranges and maintain a more northern distribution. Barndoor Skate Dipturus laevis have a moderate thermal habitat. Little Skate Leucoraja erinacea and Winter Skate L. ocellata have broad thermal ranges and are distributed throughout the management area. Limited inferences can be made about the thermal preferences of Clearnose Skate Raja eglanteria without data from south of Cape Hatteras, but they appear to have a broad thermal range within the management area. Rosette Skate L. garmani have a narrow thermal range and tend to be found in the deep offshore mid-Atlantic region. The validity of managing multiple distinct species in a complex is questioned. This example shows that a mixed-stock management strategy may be inadequate to meet the sustainability needs of each species and the associated fisheries. A management strategy focused on individual species may lead to a more efficient harvest of targeted species while allowing for the rebuilding of overfished species. © American Fisheries Society 2013. Source

Harmata A.,Montana State University | Montopoli G.,Arizona Western College
Journal of Raptor Research | Year: 2013

We made up to 12 measurements of 79 captured Golden Eagles (Aquila chrysaetos canadensis) to evaluate best metrics for noninvasive, morphometric determination of sex. Sex of 43 male and 36 female Golden Eagles was confirmed post-release: 60 by DNA analysis and 19 by position during copulation. Eagles in adult plumage made up 57% of eagles of confirmed sex. All male and female morphometric means differed (P < 0.01) but most (n = 10) metric ranges overlapped >10% between sexes. There was no overlap between sexes for the hallux claw (HAL) and head length (HEAD) metrics, regardless of age class. All male HAL and HEAD measurements were ≤51.7 mm and 119.5 mm, respectively. All female HAL and HEAD metrics were ≥51.6 mm and 119.8 mm, respectively. Multiple regression analysis indicated HAL and HEAD metrics were best of 12 morphometrics as indicators of sex (P < 0.04). Factorial ANOVAs showed no effect of age class and age class-by-sex interaction on dependent variables HAL and HEAD (P > 0.05). Sex assignments by plotting HAL and HEAD metrics of known-sex eagles relative to bivariate normal probability distribution (BNPD) percentile curves were 100% correct. Discriminate score (DS) derived from discriminate function analysis (DFA) incorporating HAL and HEAD metrics classified our sample eagles with 100% accuracy. Confirmatory analyses were 100% accurate. We also evaluated Bortolotti's (1984, Journal of Field Ornithology 55:54-66) methods of sex assignment using eagles we captured: culmen length (CL) and HAL correctly identified 89% of our known-sex eagles. Six of seven (86%) incorrect designations using his age-class dependent models were males classified as females, likely due to the variable effects of overgrown CLs or shrinkage in the museum specimens Bortolotti used. We propose using empirical data-driven BNPD plots first and then DS models if needed to assign sex to Golden Eagles >3.5 mo old in the field. Magnitude of the species' sexual dimorphism may mask clinal differences in intrasex HAL and HEAD metrics throughout the species' latitudinal range and these metrics may be accurate indicators of sex, regardless of age or region of origin in western North America. © The Raptor Research Foundation, Inc. Source

Alvarado S.,Arizona Western College | Calvo J.A.,Ave Maria University | Millett K.C.,University of California at Santa Barbara
Journal of Statistical Physics | Year: 2011

Freely jointed random equilateral polygons serve as a common model for polymer rings, reflecting their statistical properties under theta conditions. To generate equilateral polygons, researchers employ many procedures that have been proved, or at least are believed, to be random with respect to the natural measure on the space of polygonal knots. As a result, the random selection of equilateral polygons, as well as the statistical robustness of this selection, is of particular interest. In this research, we study the key features of four popular methods: the Polygonal Folding, the Crankshaft Rotation, the Hedgehog, and the Triangle Methods. In particular, we compare the implementation and efficacy of these procedures, especially in regards to the population distribution of polygons in the space of polygonal knots, the distribution of edge vectors, the local curvature, and the local torsion. In addition, we give a rigorous proof that the Crankshaft Rotation Method is ergodic. © 2011 Springer Science+Business Media, LLC. Source

Hinojosa-Prieto H.R.,University of Cologne | Vidal-Solano J.R.,University of Sonora | Kibler K.W.,Prewitt and Associates Inc | Hinojosa-Garcia H.J.,Arizona Western College
Boletin de la Sociedad Geologica Mexicana | Year: 2016

The Selene perlite ore deposit of northeastern Sonora, Mexico, lies at the southern edge of an extensive (85 × 35 km) assemblage of Early Oligocene-Miocene volcanic rocks. This fault-bounded and east-tilted volcanic assemblage is of variable composition and was erupted onto Cretaceous non-volcanic rocks. The volcanic ridge is located within the tectonically extended region of the northern Sierra Madre Occidental (SMO) silicic large igneous province. Geologic mapping reveals a faulted and uplifted bimodal volcanic sequence, dated as Late Oligocene, that contains more perlite outcrops than previously recognized and two new coplanar normal faults of Early Miocene age or younger that promoted the development of an adjacent, small half-graben filled by a volcaniclastic unit. The bimodal volcanic sequence comprises a basal Early Eocene rhyolitic lava and rhyolitic tuff overlain by a rhyolitic ignimbrite sheet, a middle flow-banded rhyolitic lava dome that hosts the Selene perlite flow, and the upper basalt on an erosional unconformity. The volcaniclastic unit rests in angular unconformity with the bimodal volcanic sequence, and was likely deposited in the Early Miocene. It comprises a lower fault breccia containing clasts of local eruptive products, a previously unidentified thin quartz arenite bed, and an upper, thick polymictic conglomerate containing clasts of perlite, rhyolite, andesite, and basalt. Potential sources for the bimodal (silicic and mafic) volcanic facies are distal and proximal-distal volcanic fissure vents, the locations of which were controlled by pre-existing NW-SE and N-S normal faults and related fractures linked to the Mexican Basin and Range Extensional Province. This implies the bimodal volcanism to be synchronous with crustal extension, as recently shown for other areas of the SMO silicic large igneous province. Normal faulting in the area also influenced the formation, preservation, and exposure (uplift) of the Selene perlite flow. The structural discontinuities created a permeable uppermost crust that channeled meteoric water into the subsurface and promoted both the percolation and underground circulation of meteoric water and gases rising into the subsurface. The water-lava interactions led to the hydration of the flow-banded rhyolitic lava flow and the formation of huge amounts of perlite. The Selene perlite was partly preserved by the overlying basalt, but continued local normal faulting and subsequent erosion exposed the perlite ore at its current location. Source

Bowker M.A.,Rey Juan Carlos University | Munoz A.,Speedway | Martinez T.,Arizona Western College | Lau M.K.,Northern Arizona University
Journal of Arid Environments | Year: 2012

During 2001-2003, a severe sub-continental drought resulted in a mortality event involving multiple woody plant species. Mass-mortality (up to 65% mortality in the locality studied) of the most drought resistant tree in the region, Juniperus monosperma (Engelm)Sarq., resulted in a conspicuously heterogeneous dieback pattern. Mortality was over three times greater in grassland landscapes compared to adjacent woodlands. We investigated the relative importance of biotic stressors (abundance of grass, tree density), edaphic stressors (soil texture), and climatic stressors (heat load) in determination of mortality. Using a multivariate modeling approach we separated the correlated edaphic and climatic influences, and determined that soil texture was the primary driver. We hypothesize that hydraulic failure in juniper was influenced by small-scale variation in matrix water potential (ψm). Density of tree stands also exerted an apparent competitive effect in grasslands and an apparent facilitative effect in woodlands. This study offers a rare glimpse of the extreme drought response of an anisohydric tree. The characteristics of sites with high juniper mortality may allow insight into the consequences of climate change impacts, enabling prediction of the types of sites which may be affected in the future. © 2011. Source

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