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Box Elder, NY, United States

The State University of New York College at Cortland, also officially called SUNY Cortland or informally known as Cortland State, is a coeducational university located in Cortland, New York, United States. In each of the four years to 2010, SUNY Cortland was named to the President's Higher Education Community Service Honor Roll and ranked by Kiplinger's among its 100 Best Values Among Public College and Universities. Wikipedia.

Gowdy J.,Rensselaer Polytechnic Institute | Krall L.,SUNY Cortland
Behavioral and Brain Sciences

Ultrasociality refers to the social organization of a few species, including humans and some social insects, having complex division of labor, city states and an almost exclusive dependence on agriculture for subsistence. We argue that the driving forces in the evolution of these ultrasocial societies were economic. With the agricultural transition, species could directly produce their own food and this was such a competitive advantage that those species now dominate the planet. Once underway, this transition was propelled by the selection of within-species groups that could best capture the advantages of (1) actively managing the inputs to food production, (2) a more complex division of labor, and (3) increasing returns to larger scale and larger group size. Together these factors reoriented productive life and radically altered the structure of these societies. Once agriculture began, populations expanded as these economic drivers opened up new opportunities for the exploitation of resources and the active management of inputs to food production. With intensified group-level competition, larger populations and intensive resource exploitation became competitive advantages and the “social conquest of earth” was underway. Ultrasocial species came to dominate the earth's ecosystems. Ultrasociality also brought a loss of autonomy for individuals within the group. We argue that exploring the common causes and consequences of ultrasociality in humans and the social insects that adopted agriculture can provide fruitful insights into the evolution of complex human society. Copyright © Cambridge University Press 2015 Source

Emam M.H.,SUNY Cortland
Classical and Quantum Gravity

We study the embedding of flat BPS three-branes in five-dimensional N = 2 supergravity theory. We derive the branes' dynamical equations as well as general expressions for the hypermultiplet fields then focus on a single brane and study its time evolution. It is shown that the brane's Hubble parameter correlates with the moduli of the underlying manifold's complex structure. For certain particular solutions, the moduli seem to exhibit an instability, being large valued at early times then rapidly decaying to either zero or some convergent constant value. The possibility of extending these results to the cosmology of our Universe is implied and briefly discussed. Our results are in line with the production and decay of heavy moduli in the early Universe, as is currently believed in the literature. © 2015 IOP Publishing Ltd. Source

Emam M.H.,SUNY Cortland
Classical and Quantum Gravity

We review the major mathematical concepts involved in the dimensional reduction of D = 11 N = 11 supergravity theory over a Calabi-Yau manifold with non-trivial complex structure moduli resulting in ungauged D = 5 supergravity theory with hypermultiplets. The latter has a particularly rich structure with many underlying geometries. We reproduce the entire calculation and particularly emphasize its symplectic symmetry and how that arises from the topology of the underlying subspace. The review is intended to fill a specific gap in the literature with the hope that it will be useful to both the beginner and the expert alike. © 2010 IOP Publishing Ltd. Source

Emam M.H.,SUNY Cortland
Physical Review D - Particles, Fields, Gravitation and Cosmology

We study the scalar fields of the five-dimensional N=2 hypermultiplets using the method of symplectic covariance developed in previous work. For static spherically symmetric backgrounds, we show that exactly two possibilities exist. One of them is a Bogomol'nyi-Prasad-Sommerfeld zero-brane carrying charge under the hypermultiplets. We find an explicitly symplectic solution of the fields in this background and derive the conditions required for a full spacetime understanding. © 2012 American Physical Society. Source

Zheng H.,Northwestern University | Chatfield C.H.,SUNY Cortland | Liles M.R.,Auburn University | Cianciotto N.P.,Northwestern University
Infection and Immunity

Iron acquisition is critical to the growth and virulence of Legionella pneumophila. Previously, we found that L. pneumophila uses both a ferrisiderophore pathway and ferrous iron transport to obtain iron. We now report that two molecules secreted by L. pneumophila, homogentisic acid (HGA) and its polymerized variant (HGA-melanin, a pyomelanin), are able to directly mediate the reduction of various ferric iron salts. Furthermore, HGA, synthetic HGA-melanin, and HGA-melanin derived from bacterial supernatants enhanced the ability of L. pneumophila and other species of Legionella to take up radiolabeled iron. Enhanced iron uptake was not observed with a ferrous iron transport mutant. Thus, HGA and HGA-melanin mediate ferric iron reduction, with the resulting ferrous iron being available to the bacterium for uptake. Upon further testing of L. pneumophila culture supernatants, we found that significant amounts of ferric and ferrous iron were associated with secreted HGA-melanin. Importantly, a pyomelanin-containing fraction obtained from a wild-type culture supernatant was able to stimulate the growth of iron-starved legionellae. That the corresponding supernatant fraction obtained from a nonpigmented mutant culture did not stimulate growth demonstrated that HGA-melanin is able to both promote iron uptake and enhance growth under iron-limiting conditions. Indicative of a complementary role in iron acquisition, HGA-melanin levels were inversely related to the levels of siderophore activity. Compatible with a role in the ecology and pathogenesis of L. pneumophila, HGA and HGA-melanin were effective at reducing and releasing iron from both insoluble ferric hydroxide and the mammalian iron chelates ferritin and transferrin. © 2013, American Society for Microbiology. Source

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