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Wayne, NE, United States

Wayne State College is a four-year public college in the Nebraska State College System in Wayne, Nebraska, United States. The current enrollment is 3,571. The college opened as a State Normal School in 1910 after the State purchased the private Nebraska Normal College . The State Normal College became State Normal School and Teacher's College in 1921. This was changed to Nebraska State Teachers College at Wayne in 1949 and the present name was adopted in 1963. Wikipedia.

Introduction: We examined the individual patterns of responses for electromyographic (EMG) amplitude and mean power frequency (MPF) during incremental treadmill running. Methods: Nine physically active men performed incremental treadmill running at a constant grade of 1%. The EMG signal was recorded from the 3 superficial quadriceps femoris muscles during the work bout. Results: The results of the polynomial regression indicated that the linear model best fit the data for the composite data for all 3 muscles and the majority (7 of 9) of subjects. There were no consistent patterns of responses for the EMG MPF responses. Also, there were no significant (P>0.05) muscle × running velocity interactions for EMG amplitude and MPF. Conclusions: These results indicate consistent patterns of responses for EMG amplitude during incremental treadmill running, regardless of which muscle was studied. © 2013 Wiley Periodicals, Inc.

Hart A.S.,University of North Texas | Chandra Bikram K.C.,University of North Texas | Subbaiyan N.K.,University of North Texas | Karr P.A.,Wayne State College | D'Souza F.,University of North Texas
ACS Applied Materials and Interfaces | Year: 2012

Effect of positioning of the cyanoacrylic acid anchoring group on ring periphery of phenothiazine dye on the performance of dye-sensitized solar cells (DSSCs) is reported. Two types of dyes, one having substitution on the C-3 aromatic ring (Type 1) and another through the N-terminal (Type 2), have been synthesized for this purpose. Absorption and fluorescence studies have been performed to visualize the effect of substitution pattern on the spectral coverage and electrochemical studies to monitor the tuning of redox levels. B3LYP/6-31G* studies are performed to visualize the frontier orbital location and their significance in charge injection when surface modified on semiconducting TiO2. New DSSCs have been built on nanocrystalline TiO2 according to traditional two-electrode Grätzel solar cell setup with a reference cell based on N719 dye for comparison. The lifetime of the adsorbed phenothiazine dye is found to be quenched significantly upon immobilizing on TiO2 suggesting charge injection from excited dye to semiconducting TiO2. The performances of the cells are found to be prominent for solar cells made out of Type 1 dyes compared to Type 2 dyes. This trend has been rationalized on the basis of spectral, electrochemical, computational, and electrochemical impedance spectroscopy results. © 2012 American Chemical Society.

Wu W.-C.V.,Providence University | Yen L.L.,National Central University | Marek M.,Wayne State College
Educational Technology and Society | Year: 2011

Teachers of English as a Foreign Language (EFL) in Taiwan often use an outdated lecture-memorization methodology resulting in low motivation, confidence, and ability on the part of students. Innovative educators are exploring use of technology, such as videoconferences with native speakers, to enrich the classroom; however few guidelines have been developed for effective videoconference instructional design. This study used a survey methodology, Exploratory Factor Analysis, and Structural Equation Modeling to examine which elements of learning via videoconferencing most beneficially affect motivation, confidence, and ability. The study found that long-term changes in ability are best predicted by enjoyment of the learning experience. The data also suggested that even a small amount of authentic interaction in English made students more comfortable in applying their skills, more confident in what they learned, and more inspired to make global, cross-cultural connections. Therefore, EFL instructors should strive to use student-centered active learning and to offer their students interactions with native speakers, including interactions via distance technology. © International Forum of Educational Technology & Society (IFETS).

Bandi V.,University of North Texas | Gobeze H.B.,University of North Texas | Karr P.A.,Wayne State College | D'Souza F.,University of North Texas
Journal of Physical Chemistry C | Year: 2014

Electron transfer is one of the most fundamental and prevalent processes occurring in chemistry, physics, and biology. In donor-acceptor systems with one of the partners' a photosensitizer, upon photoexcitation, transfer of an electron between the photoexcited and ground-state molecules occurs. Factors affecting the geometry, energetics, and dynamics of this process have been one of the intensively studied scientific topics, often by building model donor-acceptor conjugates or by utilizing natural systems. A wealth of information, applicable to almost all areas of modern science and technology, has been generated from these studies. In the present study, we demonstrate preferential through-space charge separation and charge recombination in supramolecular triads composed of porphyrin (free-base, zinc, or magnesium at the central cavity) as excited-state electron donor, BF2-chealted azadipyrromethene (azaBODIPY), and fullerene (C60) as electron acceptors. Because of spatial close proximity of the terminal porphyrin and fullerene entities of the triads as a consequence of the V-type configuration, photoinduced charge separation from the singlet excited porphyrin involves fullerene instead of energetically more favorable covalently linked azaBODIPY entity. Interestingly, charge recombination also follows this path of through-space instead of an electron migration from the fullerene anion radical to the covalently linked azaBODIPY entity. The present study highlights the importance of geometric disposition of donor and acceptor entities in governing not only the forward photoinduced electron transfer but also the dark reverse electron transfer in multimodular donor-acceptor conjugates, applicable toward light-energy-harvesting and building optoelectronic devices. © 2014 American Chemical Society.

Kc C.B.,University of North Texas | Lim G.N.,University of North Texas | Karr P.A.,Wayne State College | D'Souza F.,University of North Texas
Chemistry - A European Journal | Year: 2014

A multimodular donor-acceptor tetrad featuring a bis(zinc porphyrin)-(zinc phthalocyanine) ((ZnP-ZnP)-ZnPc) triad and bis-pyridine-functionalized fullerene was assembled by a "two-point" binding strategy, and investigated as a charge-separating photosynthetic antenna-reaction center mimic. The spectral and computational studies suggested that the mode of binding of the bis-pyridine-functionalized fullerene involves either one of the zinc porphyrin and zinc phthalocyanine (Pc) entities of the triad or both zinc porphyrin entities leaving ZnPc unbound. The binding constant evaluated by constructing a Benesi-Hildebrand plot by using the optical data was found to be 1.17×105 M-1, whereas a plot of "mole- ratio" method revealed a 1:1 stoichiometry for the supramolecular tetrad. The mode of binding was further supported by differential pulse voltammetry studies, in which redox modulation of both zinc porphyrin and zinc phthalocyanine entities was observed. The geometry of the tetrad was deduced by B3LYP/6-31G* optimization, whereas the energy levels for different photochemical events was established by using data from the optical absorption and emission, and electrochemical studies. Excitation of the zinc porphyrin entity of the triad and tetrad revealed ultrafast singlet-singlet energy transfer to the appended zinc phthalocyanine. The estimated rate of energy transfer (kENT) in the case of the triad was found to be 7.5×1011 s-1 in toluene and 6.3×10 11 s-1 in o-dichlorobenzene, respectively. As was predicted from the energy levels, photoinduced electron transfer from the energy-transfer product, that is, singlet-excited zinc phthalocyanine to fullerene was verified from the femtosecond-transient spectral studies, both in o-dichlorobenzene and toluene. Transient bands corresponding to ZnPc+ in the 850 nm range and C60 - in the 1020 nm range were clearly observed. The rate of charge separation, kCS, and rate of charge recombination, kCR, for the (ZnP-ZnP)-ZnPc+:Py 2C60 - radical ion pair (from the time profile of 849 nm peak) were found to be 2.20×1011 and 6.10×108 s-1 in toluene, and 6.82×10 11 and 1.20×109 s-1 in o-dichlorobenzene, respectively. These results revealed efficient energy transfer followed by charge separation in the newly assembled supramolecular tetrad. Artificial photosynthesis: Occurrence of ultrafast energy transfer (EnT) and electron transfer leading to the formation of a charge-separated (CS) state is demonstrated in a new donor-acceptor supramolecular tetrad comprising a bis(zinc porphyrin)-(zinc phthalocyanine) linked to fullerene as a photosynthetic antenna-reaction center mimic (see scheme). © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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