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River Road, NC, United States

Fayetteville State University is a historically black, regional university in Fayetteville, North Carolina, United States. FSU is part of the University of North Carolina System and the Thurgood Marshall College Fund. Wikipedia.


Cui Z.,Fayetteville State University
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2011

We present a kinetic model for flowing active suspensions and analyze the behavior of a suspension subjected to a weak steady shear. Asymptotic solutions are sought in Deborah number expansions. At the leading order, we explore the steady states and perform their stability analysis. We predict the rheology of active systems including an activity thickening or thinning behavior of the apparent viscosity and a negative apparent viscosity depending on the particle type, flow alignment, and the anchoring conditions, which can be tested on bacterial suspensions. We find remarkable dualities that show that flow-aligning rodlike contractile (extensile) particles are dynamically and rheologically equivalent to flow-aligning discoid extensile (contractile) particles for both tangential and homeotropic anchoring conditions. Another key prediction of this work is the role of the concentration of active suspensions in controlling the rheological behavior: The apparent viscosity may decrease with the increase of the concentration. © 2011 American Physical Society. Source


It is important to demonstrate evolutionary principles in such a way that they cannot be countered by creation science. One such way is to use creation science itself to demonstrate evolutionary principles. Some creation scientists use classic multidimensional scaling (CMDS) to quantify and visualize morphological gaps or continuity between taxa, accepting gaps as evidence of independent creation and accepting continuity as evidence of genetic relatedness. Here, I apply CMDS to a phylogenetic analysis of coelurosaurian dinosaurs and show that it reveals morphological continuity between Archaeopteryx, other early birds, and a wide range of nonavian coelurosaurs. Creation scientists who use CMDS must therefore accept that these animals are genetically related. Other uses of CMDS for evolutionary biologists include the identification of taxa with much missing evolutionary history and the tracing of the progressive filling of morphological gaps in the fossil record through successive years of discovery. © 2010 The Author. Journal Compilation © 2010 European Society For Evolutionary Biology. Source


Senter P.,Fayetteville State University
Acta Palaeontologica Polonica | Year: 2010

The stegosaurian forelimb is usually portrayed with the metacarpals slanted and distally spread. However, manual manipulation of stegosaurian metacarpals reveals that in that configuration they do not articulate with each other nor with the rest of the forelimb. Rather, they do articulate with each other and with the rest of the forelimb when posed vertically and arranged in a compact, semi-tubular configuration, as in sauropods. This configuration agrees with data from articulated specimens and trackways. As with sauropods, this metacarpal configuration makes retention of phalanges awkward for locomotion and may be functionally related to the vestigiality of the manual phalanges of the outer digits. Source


Umantsev A.,Fayetteville State University
Acta Materialia | Year: 2013

I present a theory which explains the appearance of an amorphous-like, disordered phase in nanoparticles of binary alloys. The theory claims that this phase represents a transition state between two bulk phases of the binary system. While the transition state is completely unstable in the conditions of an open system, where exchange of the species between the particle and its surrounding is not limited, it may become stabilized in the closed system where the species exchange is prohibited. I derive the material-parameters criterion, which is the condition for the stabilization. The transition state represents a shallow minimum of the molar Helmholtz free energy as a function of the order parameter and is not significant in a large system because the global optimum there is delivered by the heterogeneous mixture of the two bulk phases connected by the common-tangent construction. However, in a particle of the size below the critical, the transition state becomes the global optimizer because of the prohibitively large energy "cost" of the phase separating interface. Thus the theory explains the effect as due to the free energy of the phase separating interface, not the energy of the free surface of the particle. The theory sheds light on the structure of the critical nuclei in the process of nucleation of one phase from another one. New experiments to verify the theory are suggested. © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. Source


The Yellow Cat Member of the Cedar Mountain Formation (Early Cretaceous, Barremian?--Aptian) of Utah has yielded a rich theropod fauna, including the coelurosaur Nedcolbertia justinhofmanni, the therizinosauroid Falcarius utahensis, the troodontid Geminiraptor suarezarum, and the dromaeosaurid Utahraptor ostrommaysorum. Recent excavation has uncovered three new dromaeosaurid specimens. One specimen, which we designate the holotype of the new genus and species Yurgovuchia doellingi, is represented by a partial axial skeleton and a partial left pubis. A second specimen consists of a right pubis and a possibly associated radius. The third specimen consists of a tail skeleton that is unique among known Cedar Mountain dromaeosaurids. Y. doellingi resembles Utahraptor ostrommaysorum in that its caudal prezygapophyses are elongated but not to the degree present in most dromaeosaurids. The specimen represented by the right pubis exhibits a pronounced pubic tubercle, a velociraptorine trait that is absent in Y. doellingi. The specimen represented by the tail skeleton exhibits the extreme elongation of the caudal prezygapophyses that is typical of most dromaeosaurids. Here we perform a phylogenetic analysis to determine the phylogenetic position of Y. doellingi. Using the resulting phylogeny as a framework, we trace changes in character states of the tail across Coelurosauria to elucidate the evolution of the dromaeosaurid tail. The new specimens add to the known diversity of Dromaeosauridae and to the known diversity within the Yellow Cat paleofauna. Phylogenetic analysis places Y. doellingi in a clade with Utahraptor, Achillobator, and Dromaeosaurus. Character state distribution indicates that the presence of intermediate-length caudal prezygapophyses in that clade is not an evolutionarily precursor to extreme prezygapophyseal elongation but represents a secondary shortening of caudal prezygapophyses. It appears to represent part of a trend within Dromaeosauridae that couples an increase in tail flexibility with increasing size. Source

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