Dallas, TX, United States

Southern Methodist University

Dallas, TX, United States

Southern Methodist University is a private research university in University Park, a separate city inside the borders of Dallas, Texas. Founded in 1911 by the Methodist Episcopal Church, South, SMU operates satellite campuses in Plano, Texas, and Taos, New Mexico. SMU is owned by the South Central Jurisdiction of the United Methodist Church. 6,300 of the University's 10,800 students are undergraduates. Wikipedia.

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The present invention describes a speech enhancement method using microphone arrays and a new iterative technique for enhancing noisy speech signals under low signal-to-noise-ratio (SNR) environments. A first embodiment involves the processing of the observed noisy speech both in the spatial- and the temporal-domains to enhance the desired signal component speech and an iterative technique to compute the generalized eigenvectors of the multichannel data derived from the microphone array. The entire processing is done on the spatio-temporal correlation coefficient sequence of the observed data in order to avoid large matrix-vector multiplications. A further embodiment relates to a speech enhancement system that is composed of two stages. In the first stage, the noise component of the observed signal is whitened, and in the second stage a spatio-temporal power method is used to extract the most dominant speech component. In both the stages, the filters are adapted using the multichannel spatio-temporal correlation coefficients of the data and hence avoid large matrix vector multiplications.

Southern Methodist University | Date: 2016-10-07

The present invention includes a system, apparatus and method for generating a three-dimensional image, the system comprising: a medium comprising a optical molecular switch molecule, wherein the optical molecular switch molecule has a non-fluorescent state and a fluorescent state, wherein at one wavelength of optical excitation the molecule has a first state, and at a second state the molecule fluoresces a second wavelength of excitation; and at least a first light source and a second light source into the medium, wherein light emitted by the at least first and second light sources are directed to contact the optical molecular switch molecule, e.g., scanning, weaving, diagonally or other pattern; wherein the optical molecular switch molecule is converted into a fluorescent on state by irradiation from the first light source, and the second light causes the optical molecular switch to emit light.

Southern Methodist University | Date: 2017-01-13

The present disclosure provides a method of treating a subject that is resistant to one or more drugs by identifying a subject having one or more drug resistant cells; administering to the subject a pharmaceutically effective amount of an inhibitor compound, and contacting one or more drug resistant cells with the inhibitor compound to reduce the export of the inhibitor compound from the one or more drug resistant tumor cells and to block the transport of drug(s) from the one or more drug resistant cells.

Buynak J.D.,Southern Methodist University
Expert Opinion on Therapeutic Patents | Year: 2013

Introduction: New β-lactamases with ever-broadening substrate specificity are rapidly disseminating globally, thereby threatening the efficacy of our best β-lactam antibiotics. A potential solution to this problem is the development of wide-spectrum β-lactamase inhibitors, to be coadministered with existing and new β-lactams. Areas covered: This review covers the patent literature in the β-lactamase inhibitor area roughly from 2010 to 2013, with prior background being provided in the cases of key inhibitors and antibiotic/inhibitor combinations. An effort has been made to identify the strong and weak points of each inhibitor and combination. Expert opinion: Research in this field has become increasingly diverse, with several non-β-lactam inhibitor classes now assuming importance. The emphasis has been on finding inhibitors of AmpC, the extended-spectrum β-lactamases and class A and D carbapenemases that can demonstrate synergy with antibiotics against resistant Gram-negative pathogens. Progress has been made. Metallo-β-lactamases (MBL)-mediated resistance, however, represents an unmet challenge. The author believes that it will be extremely difficult to generate a selective, commercially viable MBL inhibitor with sufficient activity against NDM-1 and that alternate design strategies will need to be employed. © 2013 Informa UK, Ltd.

Pinkham A.E.,Southern Methodist University
Journal of Clinical Psychiatry | Year: 2014

The topic of social cognition has attracted considerable interest in schizophrenia over the last several years. This construct generally refers to the detection, processing, and utilization of social information and, within the field of schizophrenia, includes several skills such as recognizing emotion, understanding the thoughts and intentions of others, and interpreting social cues. Individuals with schizophrenia show significant impairments in social cognition, and these impairments are strongly related to functional outcome. Treating social cognition yields significant improvements in real-world outcomes, including social functioning and social skill. Importantly, social cognitive abilities are linked to specific neural circuits that have been shown to be abnormal in individuals with schizophrenia. Investigations of these neural networks in patients have also demonstrated that brain activation is significantly correlated with social functioning, which suggests that abnormal activation in social cognitive networks may serve as a mechanism for social dysfunction in schizophrenia. Among the many challenges in this area is the issue of measurement. There is disagreement about which tasks best measure social cognition and many existing measures show poor psychometric properties. A recent project, called the Social Cognition Psychometric Evaluation (SCOPE) study, aims to address these problems by providing the field with a well-validated battery of social cognitive tasks that can be used in treatment outcome trials. Research is honing in on the potential mechanisms of social cognitive impairment in patients, and with improved measurement, there is promise for optimizing behavioral and pharmacologic interventions and remediation strategies. © Copyright 2014 Physicians Postgraduate Press Inc.

Matyjaszewski K.,Carnegie Mellon University | Tsarevsky N.V.,Southern Methodist University
Journal of the American Chemical Society | Year: 2014

This Perspective presents recent advances in macromolecular engineering enabled by ATRP. They include the fundamental mechanistic and synthetic features of ATRP with emphasis on various catalytic/initiation systems that use parts-per-million concentrations of Cu catalysts and can be run in environmentally friendly media, e.g., water. The roles of the major components of ATRP - monomers, initiators, catalysts, and various additives - are explained, and their reactivity and structure are correlated. The effects of media and external stimuli on polymerization rates and control are presented. Some examples of precisely controlled elements of macromolecular architecture, such as chain uniformity, composition, topology, and functionality, are discussed. Syntheses of polymers with complex architecture, various hybrids, and bioconjugates are illustrated. Examples of current and forthcoming applications of ATRP are covered. Future challenges and perspectives for macromolecular engineering by ATRP are discussed. © 2014 American Chemical Society.

Ritz T.,Southern Methodist University
Journal of consulting and clinical psychology | Year: 2013

This review examines the evidence for psychosocial influences in asthma and behavioral medicine approaches to its treatment. We conducted a systematic review of the literature on psychosocial influences and the evidence for behavioral interventions in asthma with a focus on research in the past 10 years and clinical trials. Additional attention was directed at promising new developments in the field. Psychosocial factors can influence the pathogenesis and pathophysiology of asthma, either directly through autonomic, endocrine, immunological, and central nervous system mechanisms or indirectly through lifestyle factors, health behaviors, illness cognitions, and disease management, including medication adherence and trigger avoidance. The recent decade has witnessed surging interest in behavioral interventions that target the various pathways of influence. Among these, self-management training, breathing training, and exercise or physical activation programs have proved particularly useful, whereas other essential or promising interventions, such as smoking cessation, dietary programs, perception and biofeedback training, and suggestive or expressive psychotherapy, require further, more rigorous evaluation. Given the high comorbidity with anxiety and mood disorders, further evaluation of illness-specific cognitive behavior therapy is of particular importance. Progress has also been made in devising community-based and culturally tailored intervention programs. In concert with an essential medication treatment, behavioral medicine treatment of asthma is moving closer toward an integrated biopsychosocial approach to disease management.

Agency: NSF | Branch: Standard Grant | Program: | Phase: Physiolg Mechansms&Biomechancs | Award Amount: 363.17K | Year: 2016

Squids and cuttlefishes are impressive swimmers, having the ability to hover, change direction rapidly, and even swim forward and backward with ease. The key to their locomotive prowess is coordination among their pulsed jet, flapping fins, and flexible arms, but little is presently known about how these units work together throughout these animals lives as they encounter different physical environments, change developmentally, and experience dissimilar ecosystems. This project focuses on understanding how the jet, fins, and arms operate in concert to produce the necessary forces for exceptional turning, both in terms of muscle capabilities and hydrodynamics, in squid and cuttlefish of different developmental stages (hatchlings to adults). This work will involve cutting edge 3D flow visualization approaches, high-speed video analysis, and advanced mathematical tools that highlight the essential components of high-performance turns. This project promises to (1) advance our understanding of how highly maneuverable marine animals navigate through their complex habitats and (2) reveal key performance characteristics, structures, and behaviors that can be integrated potentially into the design of mechanical bio-inspired systems, such as autonomous underwater vehicles, to improve their turning/docking capabilities. This project incorporates a number of outreach projects, including demonstrations in local schools, participation in robotics competitions, development of web-based tutorials and summer camps, and presentations at aquariums and museums.

Maneuvering in the aquatic environment is a significant component of routine swimming, with proficient maneuvering being essential for predator avoidance, prey capture, and navigation. Despite its importance, understanding of the biomechanics of maneuvering behaviors is limited. An investigation of maneuvering performance in three morphologically distinct species of cephalopods is proposed here. The investigation explores three broad questions: (1) how are the fins, arms, and funnel-jet complex used in concert to maximize turning performance in adult cephalopods; (2) do the relative importance of turning rate and turning radius change over ontogeny and are fewer turning modes observed in young cephalopods; and (3) do fin, arm, and funnel musculoskeletal mechanics change over ontogeny and are such changes associated with differences in maneuvering? These questions will be addressed by collecting measurements of 3D high-speed kinematics and 2D/3D hydrodynamics of wake flows; performing mathematical analyses to quantitatively identify and categorize turning patterns; and measuring both the dynamic passive and active length-force relationship and maximum shortening velocity of muscle fibers that drive the movements used during turning and jet vectoring. The proposed work will: (1) provide data on how an ecologically important marine animal coordinates its novel dual-mode system (jet and fins) and arms to achieve high turning performance, (2) highlight the essential kinematic and hydrodynamic elements of turns, (3) offer insights into how maneuvering capabilities change over a broad ontogenetic range, and (4) provide novel data on the muscle properties of muscular hydrostatic organs and their role in turning.

Agency: NSF | Branch: Continuing grant | Program: | Phase: Systems and Synthetic Biology | Award Amount: 342.03K | Year: 2016

Plants evolved in response to advantageous and deleterious environmental variables, such as light, temperature, moisture and the threat of pests. To counteract daily stresses, and to maximize energy storage during the day, plants developed complex regulatory circuits that can predict daily (circadian) and seasonal (photoperiodic) rhythms, thus providing an evolutionary advantage and improved organism fitness. As such, plant circadian rhythms control all facets of plant growth and development, including flowering times, photosynthesis, latitudinal species distribution, and resistance to drought, cold and pests. It is estimated that greater than one third of all plant genes are under circadian control and that proper day-length measurements are imperative to the maintenance of plant growth, reproduction and crop yields. How these circadian clocks measure and adapt to a wide array of environmental signals is poorly understood. This is particularly the case for adaptation to daily and seasonal variations in the quality and quantity of environmental light. The current proposal aims to use a multidisciplinary approach to model how plants sense and adapt to changes in the intensity of blue-light in a given environment. Aside from gaining fundamental understanding of the chemical processes that govern plant photobiology, the project is likely to provide new avenues to improve crop yields and biomass production for renewable energy, and develop novel varieties of plants that are more drought and pest resistant. The project will provide unique training opportunities for undergraduate students and outreach to local science teachers and K-12 students.

How Light-Oxygen-Voltage proteins integrate environmental cues is poorly understood. The proposed research leverages recent discoveries of new signaling mechanisms that delineate adaptive responses to environmental stimuli. The concerted chemical, biophysical and synthetic biology approach will provide quantitative understanding of adaptive responses in complex signaling networks. The primary technical objectives are three fold. 1) A combination of chemical kinetics and predictive mathematical models will be developed to gain a systems level understanding of Light-Oxygen-Voltage protein function in seasonal and daily clocks. A direct result of these efforts will be a detailed understanding of how multiple chemical inputs to Light-Oxygen-Voltage protein function dictate signal transduction and optogenetic tool development. 2) The project will use the new understanding of Light-Oxygen-Voltage protein signaling networks to design synthetic gene circuits in mammalian cells, and thus enable the testing of the understanding of the network in the absence of extraneous plant proteins that may affect signal transduction. 3) The ultimate goal is to combine this understanding to guide the construction of new Arabidopsis thaliana strains that exhibit altered circadian function and plant flowering periods to demonstrate how Light-Oxygen-Voltage protein chemistry is essential for triggering systems-level adaptive changes in a plant system.

Agency: NSF | Branch: Standard Grant | Program: | Phase: Biomechanics & Mechanobiology | Award Amount: 314.52K | Year: 2016

Tiny lipid sacs, called liposomes, play a crucial role in living cells as means to store and transport material in and out of the cell. The key task of liposomes (storage and delivery to targets) requires them to be flexible enough to merge with target membranes in order to deliver their cargos, and yet to have sufficient structural stability to maintain integrity without rupturing and losing the stored material in the naturally dynamic biological environments. Therefore, understanding the mechanics of liposomes is of great interest to both fundamental and applied scientists who are developing artificial, biomimetic liposomes as targeted drug/gene delivery systems for better therapeutics. A major challenge however, is the lack of efficient engineering tools to probe the mechanical flexibility of the sub-cellular, nanoscale liposomes. The research addresses this need by developing a novel method based on nanopore technology that uses electric fields to deform liposomes and electrical measurements to characterize their shape. The overall goal is to characterize the mechanical flexibility of nano-liposomes with the ultimate goal to establish a method to study mechanical properties of nanoscale objects such as viruses and other biological samples at cellular/molecular level.

This project will advance the engineering tools for mechanical characterization of soft biological materials at the micro/nanoscale. The technology uses nanopore resistive pulse sensing to detect membrane deformation. As liposomes translocate through a nanopore, they experience strong electric stresses and physical confinement, which cause deformation. In this project, liposome shapes will be inferred from ionic current blockade, i.e., the sharp change (pulse) in ohmic resistance when a liposome is present in the pore. A theoretical model for liposome deformation in the nanopore will be developed to yield membrane mechanical properties. The method will enable both high-throughput and single-particle resolution because (1) thousands of liposomes pass through the nanopore and a resistive pulse will be recorded for each individual one, and (2) thousands of measurements on a single liposome can be made by alternating the applied electric field direction to drive back-and-forth translocation. In broader terms, this method will enable studying mechanobiology at novel unprecedented scales, which is single-virus and single-particle level.

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