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Reno, NV, United States

The University of Nevada, Reno is a teaching and research university established in 1874 and located in Reno, Nevada, USA. It is the sole land grant institution for the state of Nevada.The campus is home to the large-scale structures laboratory in the College of Engineering, which has put Nevada researchers at the forefront nationally in a wide range of civil engineering, earthquake and large-scale structures testing and modeling. The Nevada Terawatt Facility, located on a satellite campus of the university, includes a terawatt-level Z-pinch machine and terawatt-class high-intensity laser system – one of the most powerful such lasers on any college campus in the country. It is home to the University of Nevada School of Medicine, with campuses in both of Nevada's major urban centers, Las Vegas and Reno, and a health network that extends to much of rural Nevada. The faculty are considered worldwide and national leaders in diverse areas such as environmental literature, journalism, Basque studies, and social science such as psychology. It is also home to the Donald W. Reynolds School of Journalism, which has produced six Pulitzer Prize winners. The school includes 16 clinical departments and five nationally recognized basic science departments. Wikipedia.

Shearer J.,University of Nevada, Reno
Accounts of Chemical Research | Year: 2014

ConspectusNickel superoxide dismutase (NiSOD) is a nickel-containing metalloenzyme that catalyzes the disproportionation of superoxide through a ping-pong mechanism that relies on accessing reduced Ni(II) and oxidized Ni(III) oxidation states. NiSOD is the most recently discovered SOD. Unlike the other known SODs (MnSOD, FeSOD, and (CuZn)SOD), which utilize "typical" biological nitrogen and oxygen donors, NiSOD utilizes a rather unexpected ligand set. In the reduced Ni(II) oxidation state, NiSOD utilizes nitrogen ligands derived from the N-terminal amine and an amidate along with two cysteinates sulfur donors. These are unusual biological ligands, especially for an SOD: amine and amidate donors are underrepresented as biological ligands, whereas cysteinates are highly susceptible to oxidative damage. An axial histidine imidazole binds to nickel upon oxidation to Ni(III). This bond is long (2.3-2.6 Å) owing to a tight hydrogen-bonding network.All of the ligating residues to Ni(II) and Ni(III) are found within the first 6 residues from the NiSOD N-terminus. Thus, small nickel-containing metallopeptides derived from the first 6-12 residues of the NiSOD sequence can reproduce many of the properties of NiSOD itself. Using these nickel-containing metallopeptide-based NiSOD mimics, we have shown that the minimal sequence needed for nickel binding and reproduction of the structural, spectroscopic, and functional properties of NiSOD is H2N-HCXXPC.Insight into how NiSOD avoids oxidative damage has also been gained. Using small NiN2S2 complexes and metallopeptide-based mimics, it was shown that the unusual nitrogen donor atoms protect the cysteinates from oxidative damage (both one-electron oxidation and oxygen atom insertion reactions) by fine-tuning the electronic structure of the nickel center. Changing the nitrogen donor set to a bis-Amidate or bis-Amine nitrogen donor led to catalytically nonviable species owing to nickel-cysteinate bond oxidative damage. Only the amine/amidate nitrogen donor atoms within the NiSOD ligand set produce a catalytically viable species.These metallopeptide-based mimics have also hinted at the detailed mechanism of SOD catalysis by NiSOD. One such aspect is that the axial imidazole likely remains ligated to the Ni center under rapid catalytic conditions (i.e., high superoxide loads). This reduces the degree of structural rearrangement about the nickel center, leading to higher catalytic rates. Metallopeptide-based mimics have also shown that, although an axial ligand to Ni(III) is required for catalysis, the rates are highest when this is a weak interaction, suggesting a reason for the long axial His-Ni(III) bond found in NiSOD. These mimics have also suggested a surprising mechanistic insight: O2 - reduction via a "H•" tunneling event from a R-S(H+)-Ni(II) moiety to O2 - is possible. The importance of this mechanism in NiSOD has not been verified. © 2014 American Chemical Society.

Webster M.A.,University of Nevada, Reno
Journal of Vision | Year: 2011

Visual coding is a highly dynamic process and continuously adapting to the current viewing context. The perceptual changes that result from adaptation to recently viewed stimuli remain a powerful and popular tool for analyzing sensory mechanisms and plasticity. Over the last decade, the footprints of this adaptation have been tracked to both higher and lower levels of the visual pathway and over a wider range of timescales, revealing that visual processing is much more adaptable than previously thought. This work has also revealed that the pattern of aftereffects is similar across many stimulus dimensions, pointing to common coding principles in which adaptation plays a central role. However, why visual coding adapts has yet to be fully answered. © ARVO.

Derevianko A.,University of Nevada, Reno | Katori H.,University of Tokyo | Katori H.,Japan Science and Technology Agency
Reviews of Modern Physics | Year: 2011

Recently invented and demonstrated optical lattice clocks hold great promise for improving the precision of modern time keeping. These clocks aim at the 10-18 fractional accuracy, which translates into a clock that would neither lose nor gain a fraction of a second over an estimated age of the Universe. In these clocks, millions of atoms are trapped and interrogated simultaneously, dramatically improving clock stability. Here the principles of operation of these clocks are discussed and, in particular, a novel concept of magic trapping of atoms in optical lattices. Recently proposed microwave lattice clocks are also highlights and several applications that employ the optical lattice clocks as a platform for precision measurements and quantum information processing. © 2011 American Physical Society.

Kirkpatrick B.,University of Nevada, Reno
Schizophrenia Bulletin | Year: 2014

A selective review of the negative symptoms of schizophrenia is an appropriate article to result from the festschrift honoring William T. Carpenter Jr, as he has made substantial contributions in this area. This review assesses progress in 3 areas in which he has been an important investigator: the distinction between primary vs secondary negative symptoms; the appropriate design for treatment trials; and the nosology of negative symptoms. © 2014 © The Author 2014. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved.

Sneaky little SOD! A metallopeptide-based mimic of nickel-containing superoxide dismutase was used to probe the mechanism of superoxide reduction by the metalloenzyme. Kinetic studies suggest a proton-coupled electron-transfer mechanism; large H/D kinetic isotope effects (KIE) are observed. XAS studies suggest the transferred H-atom is in the form of a NiII-S(H)-Cys moiety (see graph). Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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