Wichita State University

About: Wichita State University is a education organization based out in Wichita, Kansas, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 4988 authors who have published 9563 publications receiving 253824 citations. The organization is also known as: WSU & Fairmount College.

Photosynthetic Antenna−Reaction Center Mimicry: Sequential Energy- and Electron Transfer in a Self-assembled Supramolecular Triad Composed of Boron Dipyrrin, Zinc Porphyrin and Fullerene

Abstract: A self-assembled supramolecular triad, a model to mimic the photochemical events of photosynthetic antenna−reaction center, viz., sequential energy and electron transfer, has been newly constructed and studied. Boron dipyrrin, zinc porphyrin, and fullerene respectively constitute the energy donor, electron donor, and electron acceptor segments of the antenna−reaction center mimicry. For the construction, first, boron dipyrrin was covalently attached to a zinc porphyrin entity bearing a benzo-18-crown-6 host segment at the opposite end of the porphyrin ring. Next, an alkyl ammonium functionalized fullerene was used to self-assemble the crown ether entity via ion−dipole interactions. The newly formed supramolecular triad was fully characterized by spectroscopic, computational, and electrochemical methods. Selective excitation of the boron dipyrrin moiety in the dyad resulted in energy transfer over 97% efficiency creating singlet excited zinc porphyrin. The rate of energy transfer from the decay measurement...

ATP Release, Adenosine Formation, and Modulation of Dynorphin and Glutamic Acid Release by Adenosine Analogues in Rat Hippocampal Mossy Fiber Synaptosomes

Abstract: Using a hippocampal subcellular fraction enriched in mossy fiber synaptosomes, evidence was obtained indicating that adenosine derived from a presynaptic pool of ATP may modulate the release of prodynorphin-derived peptides and glutamic acid from mossy fiber terminals. Synaptosomal ATP was released in a Ca2+-dependent manner by K+-in-duced depolarization. The rapid hydrolysis of extracellular [14C]ATP in the presence of intact mossy fiber synaptosomes resulted in the production of [14C]adenosine. Micromolar concentrations of a stable adenosine analogue, 2-chloro-adenosine, inhibited the K+-stimulated release of both dynorphin B and dynorphin A(l-8). 2-Chloroadenosine failed to suppress the evoked release of glutamic acid, measured in these same superfusates, unless the mossy fiber synaptosomes were pretreated with D-aspartic acid to deplete the cytosolic, Ca2+-independent, pool of this acidic amino acid. In synaptosomes pretreated in this manner, release of the remaining Ca2+-dependent pool of glutamic acid was significantly inhibited by NiCl2, 2-chloroadenosine, 5′-N-ethylcarboxami-doadenosine, cyclohexyladenosine, and R(-)-N6(2-phenyl-isopropyl)adenosine, but not by ATP. 2-Chloroadenosine-induced inhibition was reversed when the external CaCl2concentration was raised from 1.8 mMto 6 mM. 8-Phen-yltheophylline, an adenosine receptor antagonist, effectively blocked the inhibitory effects of 2-chloroadenosine on mossy fiber synaptosomes and significantly enhanced the K+-evoked release of both glutamic acid and dynorphin A(l-8) when added alone to the superfusion medium. These results support the proposition that depolarized hippocampal mossy fiber synaptosomes release endogenous ATP and are capable of forming adenosine from extracellular ATP, and that endogenous adenosine may act at a presynaptic site to inhibit the further release of glutamic acid and the prodynorphin-derived peptides

Gender differences in homework and test scores in Mathematics, Reading and Science at tenth and twelfth grade

Abstract: Gender differences in maths, reading, science and the amount of homework done out of school were obtained for tenth and twelfth graders from the American National Educational Longitudinal Study. Males obtained significantly higher mean scores in maths and science, and females obtained significantly higher mean scores in reading and amount of homework. There were significant correlations between test scores and amount of homework, suggesting that amount of homework contributes to test scores.

Opportunistic traffic scheduling over multiple network paths

Abstract: Multipath routing enables a network's traffic to be split among two or more possibly disjoint paths in order to reduce latency, improve throughput, and balance traffic loads. Yet, once the control plane establishes multiple routes, a policy is needed for efficiently splitting traffic among the selected paths. In this paper, we introduce opportunistic multipath scheduling (OMS), a technique for exploiting short term variations in path quality to minimize delay, while simultaneously ensuring that the splitting rules dictated by the routing protocol are satisfied. In particular, OMS uses measured path conditions on time scales of up to several seconds to opportunistically favor low-latency high-throughput paths. Consequently, OMS ensures that over longer time scales relevant for traffic management policies, traffic is split according to the ratios determined by the routing protocol. We develop a model of OMS and derive an asymptotic lower bound on the performance of OMS as a function of path conditions (mean, variance, and Hurst parameter) for self-similar traffic. An example finding from the model is that long-time-scale traffic fluctuations represented by a larger Hurst parameter improve the performance gain of OMS vs. round-robin scheduling, even under paths that are statistically identical. Finally, we use an extensive simulation-based performance study to evaluate the accuracy of the analytical model, explore the impact of OMS on TCP throughput, and study the impact of factors such as delayed measurements