Kent State University is a public research university located in Kent, Ohio, United States. The university has eight campuses around the Northeast Ohio region with the main campus in Kent being the largest. Other campuses are located in Ashtabula, Burton, East Liverpool, Jackson Township, New Philadelphia, Salem, and Warren, Ohio.As of September 2014, Kent State is one of the largest universities in Ohio with an enrollment of 41,213 students in the eight-campus system and 29,477 students at the main campus in Kent. It is ranked by the Carnegie Foundation as one of the top 77 public research universities in the US and one of the top 76 in community engagement. In 2010, Kent State was ranked as one of the top 200 universities in the world by Times Higher Education. Kent State offers over 300 degree programs, among them 250 baccalaureate, 40 associate's, 50 master's, and 23 doctoral programs of study, which include such notable programs as nursing, business, history, library science, aeronautics, journalism, fashion design and the Liquid Crystal Institute.The university was established in 1910 as the Kent State Normal School as a teacher-training school. The first classes were held in 1912 at various locations and in temporary buildings in Kent. Since then, the university has grown to include many additional baccalaureate and graduate programs of study in the arts and science, research opportunities, as well as over 1,000 acres and 119 buildings on the Kent campus. During the late 1960s and early 1970s, the university was known internationally for its student activism in opposition to US involvement in the Vietnam War, due mainly to the events of May 4, 1970. Wikipedia.
Shrestha P.,Kent State University
Nature Nanotechnology | Year: 2017
Molecular simulations suggest that the stability of a folded macromolecule increases in a confined space due to entropic effects. However, due to the interactions between the confined molecular structure and the walls of the container, clear-cut experimental evidence for this prediction is lacking. Here, using DNA origami nanocages, we show the pure effect of confined space on the property of individual human telomeric DNA G-quadruplexes. We induce targeted mechanical unfolding of the G-quadruplex while leaving the nanocage unperturbed. We find that the mechanical and thermodynamic stabilities of the G-quadruplex inside the nanocage increase with decreasing cage size. Compared to the case of diluted or molecularly crowded buffer solutions, the G-quadruplex inside the nanocage is significantly more stable, showing a 100 times faster folding rate. Our findings suggest the possibility of co-replicational or co-transcriptional folding of G-quadruplex inside the polymerase machinery in cells. © 2017 Nature Publishing Group
Xiang Q.,Wuhan University of Technology |
Yu J.,Wuhan University of Technology |
Jaroniec M.,Kent State University
Chemical Society Reviews | Year: 2012
Graphene, a single layer of graphite, possesses a unique two-dimensional structure, high conductivity, superior electron mobility and extremely high specific surface area, and can be produced on a large scale at low cost. Thus, it has been regarded as an important component for making various functional composite materials. Especially, graphene-based semiconductor photocatalysts have attracted extensive attention because of their usefulness in environmental and energy applications. This critical review summarizes the recent progress in the design and fabrication of graphene-based semiconductor photocatalysts via various strategies including in situ growth, solution mixing, hydrothermal and/or solvothermal methods. Furthermore, the photocatalytic properties of the resulting graphene-based composite systems are also discussed in relation to the environmental and energy applications such as photocatalytic degradation of pollutants, photocatalytic hydrogen generation and photocatalytic disinfection. This critical review ends with a summary and some perspectives on the challenges and new directions in this emerging area of research (158 references). © 2012 The Royal Society of Chemistry.
Bisoyi H.K.,Kent State University |
Li Q.,Kent State University
Accounts of Chemical Research | Year: 2014
ConspectusEndowing external, remote, and dynamic control to self-organized superstructures with desired functionalities is a principal driving force in the bottom-up nanofabrication of molecular devices. Light-driven chiral molecular switches or motors in liquid crystal (LC) media capable of self-organizing into optically tunable one-dimensional (1D) and three-dimensional (3D) superstructures represent such an elegant system. As a consequence, photoresponsive cholesteric LCs (CLCs), i.e., self-organized 1D helical superstructures, and LC blue phases (BPs), i.e., self-organized 3D periodic cubic lattices, are emerging as a new generation of multifunctional supramolecular 1D and 3D photonic materials in their own right because of their fundamental academic interest and technological significance. These smart stimuli-responsive materials can be facilely fabricated from achiral LC hosts by the addition of a small amount of a light-driven chiral molecular switch or motor. The photoresponsiveness of these materials is a result of both molecular interaction and geometry changes in the chiral molecular switch upon light irradiation. The doped photoresponsive CLCs undergo light-driven pitch modulation and/or helix inversion, which has many applications in color filters, polarizers, all-optical displays, optical lasers, sensors, energy-saving smart devices, and so on.Recently, we have conceptualized and rationally synthesized different light-driven chiral molecular switches that have very high helical twisting powers (HTPs) and exhibit large changes in HTP in different states, thereby enabling wide phototunability of the systems by the addition of very small amounts of the molecular switches into commercially available achiral LCs. The light-driven chiral molecular switches are based on well-recognized azobenzene, dithienylcyclopentene, and spirooxazine derivatives. We have demonstrated high-resolution and lightweight photoaddressable displays without patterned electronics on flexible substrates. The wide tunability of the HTP furnishes reflection colors encompassing the whole visible spectrum and beyond in a reversible manner. Photomodulation of the helical pitch of the CLCs has been achieved by UV, visible, and near-infrared (NIR) light irradiation. NIR-light-induced red, green, and blue (RGB) reflections have been leveraged only by varying the power density of the IR laser. Some chiral switches are found to confer helix inversion to the cholesteric systems, which qualifies the CLCs for applications where circularly polarized light is involved. Dynamic and static primary RGB reflection colors have been achieved in a single film. LC BPs have been fabricated and investigated in the context of self-organized 3D photonic band gap (PBG) materials, and dynamic phototuning of the PBG over the visible region has been achieved. Omnidirectional lasing and tuning of the laser emission wavelength have also been attained in monodisperse photoresponsive CLC microshells fabricated by a capillary-based microfluidic technique.This Account covers the research and development in our laboratory starting from the design concepts and synthesis of photodynamic chiral molecular switches to their applications in the fabrication of photoresponsive CLCs and BPs. Potential and demonstrated practical applications of photoresponsive CLCs, microshells, and BPs are discussed, and the Account concludes with a brief forecast of what lies beyond the horizon in this rapidly expanding and fascinating field. © 2014 American Chemical Society.
Lavrentovich O.D.,Kent State University
Soft Matter | Year: 2014
Colloidal particles in a liquid crystal (LC) behave very differently from their counterparts in isotropic fluids. Elastic nature of the orientational order and surface anchoring of the director cause long-range anisotropic interactions and lead to the phenomenon of levitation. The LC environment enables new mechanisms of particle transport that are reviewed in this work. Among them the motion of particles caused by gradients of the director, and effects in the electric field: backflow powered by director reorientations, dielectrophoresis in LC with varying dielectric permittivity and LC-enabled nonlinear electrophoresis with velocity that depends on the square of the applied electric field and can be directed differently from the field direction. © The Royal Society of Chemistry.
Docherty N.M.,Kent State University
Schizophrenia Bulletin | Year: 2012
Speech of people with schizophrenia is often difficult to follow. There is evidence that neuropsychological deficits associated with schizophrenia explain some of the variance in speech disorder, but its nature and causes overall are not well understood. This study rated speech samples from 60 schizophrenic outpatients for thought disorder, conceptual disorganization, linguistic structural breakdown, and communication failure. A battery of neuropsychological tests potentially relevant to coherent speech production was administered, and associations between these variables and the speech measures were assessed. Consistent with previous research, the measure of functional effect, communication failure, was more highly associated with neuropsychological test performance than were the measures of putative cause: thought disorder, conceptual disorganization, or linguistic structural breakdown. Performance on tests of attention, immediate memory, working memory, organizational sequencing, and conceptual sequencing all were significantly related to the frequency of communication failures in the speech. In hierarchical regression, attention, working memory, and conceptual sequencing each contributed significantly and together explained 29% of the variance. Some other potential contributors to test in future research include auditory attention, internal source memory, emotional disturbances, and social cognitive deficits. © The Author 2011.
Wang Y.,Kent State University |
Li Q.,Kent State University
Advanced Materials | Year: 2012
The ability to tune molecular self-organization with an external stimulus is a main driving force in the bottom-up nanofabrication of molecular devices. Light-driven chiral molecular switches or motors in liquid crystals that are capable of self-organizing into optically tunable helical superstructures undoubtedly represent a striking example, owing to their unique property of selective light reflection and which may lead to applications in the future. In this review, we focus on different classes of light-driven chiral molecular switches or motors in liquid crystal media for the induction and manipulation of photoresponsive cholesteric liquid crystal systems and their consequent applications. Moreover, the change of helical twisting powers of chiral dopants and their capability of helix inversion in the induced cholesteric phases are highlighted and discussed in the light of their molecular geometric changes. The ability to tune molecular self-organization with an external stimulus is a main driving force in the bottom-up nanofabrication of molecular devices. Light-driven chiral molecular switches or motors in liquid crystals that are capable of self-organizing into optically tunable helical superstructures undoubtedly represent such a striking example. In this review, we focus on different classes of light-driven chiral molecular switches or motors in liquid crystal media for the induction and manipulation of photoresponsive cholesteric LC systems and their consequent applications. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
GraphSQL and Kent State University | Date: 2016-05-28
Systems and methods for generating real-time, personalized recommendations are disclosed. In one embodiment, a method operates upon an electronic data collection organized as a network of vertices and edge connections between the vertices. The method provides the recommendations includes iteratively traversing across edges that satisfy search criteria to a new set of vertices and filtering each new set of vertices to satisfy the search criteria. At the conclusion of the traversing and filtering, a final set of vertices represents the recommended entities. In some embodiments, a control vector describes a sequence of relationships between a requester and the items to be recommended. The method can assign scores to candidate recommendations and select the recommendations having the highest scores. Advantageously, the method provides flexibility and rapid execution of recommendation queries without the need to precompute intermediate results.
Agency: NSF | Branch: Standard Grant | Program: | Phase: Chemical Measurement & Imaging | Award Amount: 200.00K | Year: 2016
This project is funded by the Chemical Measurement and Imaging (CMI) program of the Division of Chemistry at the National Science Foundation. Professor Hanbin Mao of Kent State University is developing new biosensing strategies that have high sensitivity to detect multiple chemical or biological targets simultaneously. Broader impacts are addressed through the development of integrated research-education projects to train high-school and college students. Many parts of research plans are modularly designed in to accommodate the tight schedules of high school and college students. This facilitates the participation of these students into the STEM fields.
This project employs individual macromolecules, such as DNA, as platforms for analyte sensing. Upon the binding of an analyte, the macromolecule changes its conformation, which is accompanied by a variation in mechanical properties, such as tension, due to the mechanochemical coupling. Using laser tweezers, the change in the mechanical property is monitored in real time, accomplishing the sensing without extra infrastructure used in a separate signal transduction unit. Since single-molecule templates are used, detection of individual molecules is the result. This represents the utmost sensitivity for biosensing. Compared to other single-molecule detection schemes such as fluorescence, the force signal employed in a mechanochemical sensor suffers little from environmental noise. In addition, the measurement of force does not require direct light excitation, which avoids photo-damage to the sensing template. All these facts render strong reliability and high sensitivity for this new sensing strategy.
Agency: NSF | Branch: Continuing grant | Program: | Phase: ANALYSIS PROGRAM | Award Amount: 200.00K | Year: 2016
The problems addressed in this project ask about properties of shapes in an ambient space (like a human heart in the body) that can be inferred from information about their shadows or slices (as in medical imaging). The advantage of the problems is that the solutions to many of them are intuitively clear not only to graduate students, but also to undergraduate students, and in some cases, even to high-school pupils! On the other hand, the answers are (very often) counterintuitive, requiring the use of the most advanced and sophisticated tools belonging to the different branches of modern mathematics. Moreover, many of the problems originated not in pure math, but in medical imaging and tomography. For this reason the solutions might find very interesting biomedical applications.
The current project is a continuation of the long-time collaboration between the two principal investigators. They will continue to use and develop the methods of harmonic analysis to solve problems arising in convex and discrete geometry. These problems include ones about Brunn-Minkowski-type inequalities for general measures, as well as questions related to different versions of slicing inequalities, including a slicing inequality for general measures and a discrete version of the slicing inequality. The principal investigators also plan to continue their work on the unique determination of convex bodies given information on the size (or some other properties) of projections and sections. This will involve a mixture of topological, probabilistic, and Fourier-analytic methods, and part of the work will be concentrated around a classical problem of Bonnensen that the principal investigators and their collaborators have previously solved in even dimensions. Many of the techniques developed in that work are new, and there are high hopes that the methods could help to solve a number of classical (but still open) questions in geometric tomography.
Agency: NSF | Branch: Standard Grant | Program: | Phase: ELECT, PHOTONICS, & MAG DEVICE | Award Amount: 150.00K | Year: 2016
Organic Transistors hold the promise of enabling flexible and low-cost electronics. One of the latest additions to this field is the Organic Permeable Base Transistor. Only recently has it been found that Organic Permeable Base Transistors reach very high output currents and operate at very low driving voltages. However, until now this excellent performance has come at the expense of significant base currents leading to static power losses and ruling out the use of Organic Permeable Base Transistors in most cases.
The project addresses this challenge. The origin of base currents is studied and approaches to suppress them are tested. If successful, the project will increase the switching speed of organic transistors by an order of magnitude, which will accelerate commercialization of flexible electronics. Additionally, the reduction of base currents of Organic Permeable Base Transistors will open new fields of application such as flexible backplanes for active matrix displays.
To broaden the impact of the project, additional measures aim at leveraging the research and using it as a vehicle to improve STEM education. The PI will develop courses targeted at high school teachers offering College Credit Plus classes. These College Credit Plus classes allow high school students to earn college credit early and free of cost, which has the potential to increase the enrollment in STEM degrees. Furthermore, selected work-packages of the proposal will be offered as Senior Honors Project to a student majoring in physics and mathematics. Furthermore, graduate students will be trained in a socially important research area, which will make them part of a globally competitive workforce. Students will participate in a summer school jointly organized with Case Western Reserve University providing them with all necessary background in organic semiconductors, device physics, and device engineering.
The goal of this project is to unravel the origin of base currents in Organic Permeable Base Transistors. The specific research objectives are a) to prove that a drift-diffusion simulation of the device can quantitatively reproduce the device behavior, in particular the magnitude of base currents and b) to test the hypothesis that a self-assembled monolayer on top of the base electrode can significantly reduce base leakage currents.
A quantitative agreement between the drift-diffusion simulation and experiment will be reached by a thorough characterization of the morphology of the base electrode and of the charge transport in all layers of the Organic Permeable Base Transistor. In particular, the growth of the porous base electrode and the nature of base currents will be studied by scanning probe methods, transmission electron microscopy, and electrical characterization of test devices. Self-organized layers of insulating phosphonic acids will be grown on top of the base. Charge transport across these layers will be quantified and modeled, leading to a concise description of Organic Permeable Base Transistors operating at significantly increased current amplification and thus lower static power dissipation.
As a result of the project, an experimentally validated model of the Organic Permeable Base Transistor will become available to the scientific community, which will significantly enhance the fundamental understanding of the device and will enable a rational design of Organic Permeable Base Transistors. Furthermore, the project will increase the knowledge on vertical charge transport in poly-crystalline organic films and will provide detailed charge carrier mobility models for standard materials used in Organic Permeable Base Transistors. Clarifying the nature of base currents will improve the understanding of injection into a disordered organic semiconductor and will lead to a quantitative description of injection from oxidized aluminum into the organic semiconductor C60.