Thomas Murray - US grants

Given the potent depressant effects of adenosine on spontaneous neuronal firing, it has been proposed that endogenous adenosine may function as an important modulator of neuronal activity involved in the etiology or control of seizures. In accordance with this proposal, metabolically stable adenosine analogs have been shown to elevate pentylenetetrazol (PTZ) seizure threshold in rats. Moreover, the seizure suppressant effects of adenosine analogs were antagonized by the adenosine receptor antagonist, theophylline. This proposal describes the use of the PTZ seizure threshold model in combination with other pharmacological, neuroanatomical and biochemical approaches to further our understanding of the involvement of adenosine in seizure mechanisms. An assignment of the adenosine receptor subtype involved in seizure suppressant effects of adenosine analogs remains to be elucidated. A rigorous pharmacological characterization of the adenosine receptor involve in the regulation of PTZ seizure threshold will be accomplished by determining the rank order potencies of several adenosine analogs administered intracerebroventricularly (i.c.v.) in rats. The rank order potencies of a series of xanthines, administered i.c.v., as proconvulsants in the PTZ seizure threshold model will also be determined. Possible correlations between the rank order potencies of adenosine analogs as seizure suppressants and their affinities for adenosine A1 receptors as labeled by (3H)cyclohexyladenosine will be explored. A delineation of the neuroanatomic substrate for the anticonvulsant actions of adenosine analogs is essential in attempts to elucidate the basic cellular and molecular mechanisms involved. To this end, the effects of adenosine analogs microinjected into various rat brain structures on PTZ seizure threshold will be determined. A further understanding of the biochemical and neuroanatomical mechanisms responsible for the effects of adenosine analogs on seizure susceptibility may provide insight into one of the basic mechanisms of seizure disorders in man.

computer graphics /printing; computer center;

The objective of the proposed research is to elucidate the molecular mechanisms by which pyrethroids exert their neurotoxicological effects in mammalian species. Specifically, these investigations will attempt to determine whether there are toxicologically relevant differences in the interaction of Type I vs Type II pyrethroids with the benzodiazepine-GABA receptor ionophore complex. Moreover, the effects of chronic exposure to pyrethroids on the characteristics and function of the GABA receptor-ionophore complex and related sites will be determined. The reported interactions of Type II pyrethroids with the GABA- gated chloride channel will be characterized in vitro and in vivo using (35S)t-butylbicyclophosphorothionate to label this ion channel. The interaction of Type I and Type II pyrethroids with the "peripheral-type" benzodiazepine receptor will also be investigated using (3H)PK 11195 as a radioligand probe for this recognition site in both in vitro and in vivo studies. The hypothesis that a novel "peripheral type" benzodiazine receptor may be functionally coupled to the GABA-gated chloride channel will be evaluated using pyrethroids as probes in the study of the allosteric modulation of (35S)-t-butylbicyclophosporothionate binding. The potential influence of chronic exposure to pyrethroids on the coupling efficiency between the chloride ion channel and GABA and benzodiazepine receptors will be assessed. The functional consequences of pyrethroid occupancy of these receptor sites will be examined by characterization of the proconvulsant actions of Type I and Type II pyrethroids against seizures elicited from an epileptogenic site in the prepiriform cortex. Correlations between receptor site occupancy in vivo and pyrethroid modulation of seizure susceptibility will be obtained. The effects of pyrethroids on GABA-gated chloride influx will be investigated in intact neurons and in synaptoneurosome preparations. Thus, both pyrethroid-neuroreceptor interaction as well as the functional consequences of activation of various ligand binding sites associated with the GABA/benzodiazepine receptor- ionophore complex will be ascertained. The results of these investigations will further our understanding of molecular mechanisms operative in the pyrethroid modulation of seizure susceptibility. The ability of PK 11195 to antagonize the proconvulsant effects of pyrethroids will be further characterized. Considered together, these results may have important clinical implications concerning potential neurotoxic sequelae of pyrethroid exposure.

The purpose of this research is to develop compounds as tools to study opioid receptors. These receptors are proteins which are responsible for both the beneficial and the undisirable effects of narcotic analgesics such as morphine. However, not all opioid receptors are identical and this has complicated the study of this receptor group. Since the demonstration of these multiple opioid receptors about fifteen years ago, numerous compounds have been prepared in attempts to differentiate the receptor types. To further complicate the issue, endogenous morphine-like substances have been isolated from animals. These compounds, opioid peptides, are fragments of other proteins and appear to be involved in a number of physiological functions including pain sensation. This research involves the preparation of derivatives of one of the opioid peptides, dynorphin. This opioid interacts with kappa-opioid receptors which are distinct from morphine receptors. The study of kappa opioid receptors may lead to the development of better nonaddictive analgesics. The opioids are synthesized containing 'affinity labels' which cause the synthetic opioid to permanently bind to the receptor. In this way, any neuroscientists or pharmacologist may use these new peptides to differentiate between the various types of opioid receptors.

Dextrorphan, (+)3-hydroxy-N-methyl-morphinan, is a selective noncompetitive antagonist of the N-methyl-D-aspartate (NMDA) class of excitatory amino acid receptors. Dextrorphan is the O-demethylated primary metabolite of the over-the-counter antitussive dextromethorphan. Dextromethorphan abuse has been documented in various countries over the last 30 years, whereas outbreaks of dextromethorphan abuse by teenagers has surfaced as a social problem recently in several cities in the U.S. The euphoriant and hallucinogenic effects of dextromethorphan and dextrorphan are similar to those of phencyclidine (PCP) and, in an analogous manner, derive from the ability of these compounds to act as antagonists of the NMDA receptor. Dextrorphan is however more potent than dextromethorphan as a NMDA receptor antagonist. Notwithstanding the commonalities of action between dextrorphan and prototypic noncompetitive NMDA antagonists such as PCP and MK-801, dextrorphan blockade of NMDA receptors has been distinguished by distinct kinetics, use-dependency and subtype selectivity. This research program is directed toward a quantitative mechanistic description of dextrorphan binding to and antagonism of the NMDA receptor ion-channel and NMDA receptor ion-channel antagonism. The central hypothesis to be evaluated is that the binding domain within the NMDA receptor ion channel recognized by dextrorphan is distinct and therefore nonidentical to the site labeled by MK-801. An interaction with distinct, yet proximate, binding domains by dextrorphan and MK-801 is posited to underlie the distinguishing pharmacological actions of these two compounds. This proposal attempts to combine kinetic analysis of ligand binding and channel antagonism with molecular biological approaches to determine the sites of interaction for dextrorphan and MK-801 in the NMDA receptor ion channel. The use of recombinant NMDA receptors will permit delineation of the molecular basis for the distinct regional and pharmacological profiles of [3/H]MK-801 and [3/H]dextrorphan labeling of NMDA receptors in rat brain. A mechanistic description of the distinctive NMDA receptor antagonism produced by dextrorphan, MK-801 and PCP analogs, will provide a further understanding of the differing propensities of these compounds to produce psychotomimetic effects.

DESCRIPTION (Adapted from Investigators' Abstract): This project is intended to provide an overview of the Genome Project's impact on access to health care by engaging 13 leading scholars in research on specific topics within their own expertise and extending that research to address the impact of the Genome Project. The project will have two types of products. One will be a book on the Genome Project and access to health care. The book will consist of an introduction and three parts. Part I will address the Genome Project's impact on health care needs, the likely availability of resources, and the investigators' concepts of health, illness, and personal responsibility for health and illness. It will include studies of clinical decision making, reproduction, minority health care, gene therapy, educating clinicians about genetics, and the concepts of genetic health and disease. Part II will examine the impact on the health care enterprise in the United States, focusing on how access will be controlled and how decisions about financing may be affected. It will incorporate studies of the impact on health insurance, government programs affecting access and reimbursement, employer health benefits, and the distribution of scarce medical resources. Part III will be written by the project's three principals, and will offer analyses of the Genome Project's overall impact on the practice medicine biomedical ethical issues, and legal issues and policy options. Where appropriate, the studies in Part III will suggest priorities for future research, as well as potential options for policy. The second set of products will be at least two scholarly articles co-authored by the three principals, aimed at journals on health policy, and science/medicine. Project results will also be disseminated by presentations at professional meetings.

biomedical equipment purchase;

Modern construction materials often result in lightweight floor systems susceptible to transient motion imparted by the input forcing function of human locomotion. Technologies intended to control this phenomena must quantify the forcing function and efficient vibration damping methods. The research will quantify the input forcing function of locomotion as a truncated Fourier Series whose coefficients are related to human physical characteristics. Extrapolation using ergonomic indices will then create a statistically based description of population locomotive trends suitable for rational structural design recommendations. The second phase of research will investigate the properties of the human body which make it an efficient damper. Experimental data will be collected from floors using humans as passive or active second mass dampers. Existing mathematical simulations will be used to analytically explain the body's damping potential. Finally, a mechanical device will be developed which emulates human body properties to control unwanted floor motion through artificially increased damping. The research will permit lightweight floor systems to operate at their true design potential, unhampered by vibration serviceability considerations. It will also ascertain analytical methods of design based on input forcing functions which are in turn based on ergonomic population means.

9453739 Riehl South Seattle Community College, Boeing Company, Eldec Corporation, Clover Park Technical College and 12 other organizations will develop a process for determining specific workplace standards for manufacturing education and training in Washington State. These standards will, in turn, lead to an industry-guided manufacturing technology core curriculum. The curriculum will begin in high schools and will feed into a 2+2 Tech Prep post-secondary community college program. A workplace-based internship will also be an integral part of the curriculum. This comprehensive, innovative proposal has strong support from both labor unions and industry. It will help bridge the gap between secondary school technical education and the requirements of the industrial workforce.

9416171 Murray Numerous reports of fractures in beam flange-to-column flange welds in steel moment resisting frames after the Northridge earthquake suggest the need for a new connection configuration. No reports of end-plate moment connection distress or failure are known. In this project the endplate and all-bolted moment connections will be studied to develop an alternate to field welded connections. Because both of these connection types require tension bolts and the associated problems with prying forces, a shim plate is placed opposite the beam tension flange or the tee-stub tension web. Using the shim ensures that the bolt tension will not increase until separation of the end-plate or tee stub flange and the column flange occurs. If the design is such that the pretension force is sufficient to develop the strength of the connected beam, in effect the connection is tested at the time the bolts are tightened. The project consists of three tasks: Task I is a survey to determine if end-plate or all-bolted moment connections exhibited distress or failure because of the Northridge earthquake. Task II is the development of a design procedure for shimmed end-plate and all-bolted moment connections, which is a relatively uncomplicated procedure because the effects of prying forces do not need to be considered. Task III is a set of four verification tests, two for each connection type. One test in each set will be designed so the connection is the controlling limit state and the second so the beam is controlling limit state. Successful completion of the proposed research will result in a steel beam-to-column moment connection which does not require welding but with sufficient strength to resist large forces from seismic events. This is a Northridge Earthquake project. ***

A STUbY -OP St-MA11 -ACTIVE MAGNETO-RHEOLOGICAL
DEVICES FOR CONTROLLING FLOOR VIBRATIONS

ABSTRACT

Excessive levels of floor vibrations due to human activities such as walkhg, jumping, and dancing have been the topic of several research studies. Unfortunately, there has only been a limited success in finding corrective measures to this problem.

This study- investigates the effectiveness of magneto-rheological (MR) devices such as MR dampers, and TVA's for reducing floor vibrations. Methodologies and guidelines will be developed for the design of these devices based on the dynamic characteristics of different floor systems. A floor test will be constructed at the Virginia Tech Structures and Materials Research Laboratory and a series of dynamic tests will be performed to provide experimental verifications of the analvtical results.

Several industries will cooperate and provide technical and financial assistance to the project principal investigators. This study will be performed by the Civil Engineering, Mechanical Engineering, and Architecture Departments of Virginia

DESCRIPTION (provided by applicant): FimX is a recently described protein in Pseudomonas aeruginosa (PA) shown to regulate type IV pill (TFP), an important virulence factor, in response to environmental signals. We propose to characterize the role of FimX, a GGDEF/EAL containing protein, in TFP assembly. We will confirm that FimX synthesizes cyclic di-GMP (c-diGMP), a regulatory molecule hypothesized to be important for a wide variety of cellular functions. The contributions of each FimX domain to regulation of c-diGMP will be elucidated. We have identified two components of ABC transporters that partner with FimX in a yeast two-hybrid screen. We will confirm these interactions with co-immunoprecipitation studies and identify the FimX domains required to bind these proteins. Furthermore, we will generate PA strains lacking these ABC transporters and confirm their role in the regulation of TFP. Additional studies will determine if these transporters are exporters or importers. These studies will determine whether c-diGMP is a second messenger regulating twitching motility in PA. We also will characterize the first ABC transporters identified in PA involved in controlling TFP expression.

Study of the Effects of Non-Structural Building Elements and Human-Structure Interaction on the Dynamic Behavior of Floors Subjected to Human Movements

Mehdi Setareh, and Thomas M. Murray

PROJECT SUMMARY

Recent advances in the development of higher strength materials coupled with more efficient construction techniques, more accurate computer-assisted structural analysis and design, new design methods, and more common use of long-span structures by architects have resulted in many floors that are susceptible to annoying floor vibrations due to walking, jumping, dancing, and similar activities.
Even though this problem has been studied during the past thirty years, problem floors have become an increasingly common occurrence. These problems are mainly due to a lack of accurate definition of the dynamic parameters of floors, which in turn have caused poor correlations between the levels of measured and predicted vibrations by various design guides and particularly finite element analyses. Two major issues that have been mainly ignored in previous research are the effects of non-structural elements and the effects of the interaction of occupants and structure on the floor system. Most non-structural building elements are designed and detailed by non-engineers, mainly architects. Unfortunately, there is a lack of awareness of this problem among architects.
The proposed research project intends to address the above problems. A two-story structure will be constructed at the Virginia Tech Research Center to act as a full-scale test model for a series of dynamic tests representative of the analytical excitations. It is estimated that the construction of the testing facility will be completed within the first eighteen months from the project starting date. A short pilot study to consider the effects of the non-structural elements and human-structure interactions will be conducted during the remainder of this two-year research effort.
The broader impacts of this project are: First, the test structure will be a permanent center for the study of floor vibrations. Industries interested in the development of new products to address this problem will be able to use the facility to test their products. This will be a collaborative effort between the College of Architecture and Urban Studies and the College of Engineering of Virginia Tech. Students in the architecture and civil engineering programs will have access to this facility for their research projects, and help them understand the different aspects of this problem. The PIs will incorporate the results of this research into their architecture and civil engineering courses. All efforts will be made to involve students in the under-represented groups and minorities in this research. In addition, undergraduate students will be included through the NSF-REU program.

DESCRIPTION (provided by applicant): In patients with cystic fibrosis (CF), chronic colonization of the lungs with Pseudomonas aeruginosa results in frequent hospitalizations and in premature mortality. P. aeruginosa can colonize surfaces in multiple ways: swarming motility, sliding motility and the formation of biofilms. Expression of components on the surface of the bacteria (e.g. type IV pili, exopolysaccharide, flagella, and rhamnolipids) is important for these activities, but current understanding of the interactions and co-regulation of these factors is incomplete. Dr. Murray has preliminary evidence that certain regulatory proteins produced by P. aeruginosa each controls multiple factors important for colonization. His research goals are to: 1) Determine the components required for surface colonization co-regulated by these proteins (using strains of P. aeruginosa that variously lack these regulatory proteins and measuring levels of pilin, flagellin, exopolysaccharide, and rhamnolipid during swarming, sliding and formation of biofilms);2) To quantitate the colonization of surfaces by these strains in a CF tissue culture model of infection (by visualizing bacterial/epithelial cell interactions with confocal microscopy and analyzing these images with COMSTAT software);and 3) To correlate in vitro surface colonization defects with abnormal chronic colonization in vivo (by measuring the recovery of bacteria, histology, and the immune response in the lungs of rats infected with these strains). Understanding these processes may lead to novel therapies. Dr. Murray will complement his experience in microbiology by learning new techniques: real time PCR, confocal microscopy, a CF tissue culture model, and a rat model of chronic pneumonia. Dr Murray's primary mentor has expertise in animal infection models and his advisory committee includes experts in microbial pathogenesis and the director of Yale's CF Center who will teach him these skills. He will take courses in translational research, immunobiology, and animal care. Through this additional training, Dr. Murray will gain the tools to become an independent investigator in the pathogenesis of chronic infection by Pseudomonas. RELEVANCE (See instructions): The bacterium Pseudomonas aeruginosa lives in the lungs of people with cystic fibrosis for many years, resulting in frequent hospitalizations. Current antibiotic therapies are not successful in eliminating the bacteria and new approaches to therapy are needed. The goal of this project is to better understand the properties of P. aeruginosa that allow it to survive in the lung so new therapies may be developed.

This project will develop and evaluate software to support people engaged in online social deliberation, especially as it relates to dispute resolution and collaborative inquiry. The software will model and monitor deliberative processes skills while people are either in collaboration or involved in settling disputes. Applications will be in three domains that already support online conversations: 1) online dispute resolution (e.g., eBay and the U.S. National Mediation Board); 2) collaborative learning in open-ended inquiry learning environments; and 3) dialog and deliberation on civic and ethical issues. The project will scaffold situations, adding structure or focusing attention on social processes, support improvement of individual skills, and facilitate a. Wisdom of crowds that enables participants to produce improved results. This project involves faculty across five departments: legal studies, psychology, political science, computer science and education.

Intellectual Merit. This research advances social issues (collaboration, dispute resolution, and critical thinking) and computation techniques (online dispute resolution, argumentation and collaboration). It furthers research into building social communities, explores issues of coaching and collaboration and develops evaluation tools for measuring the effect of online support.

Broader Societal Impact. This project advances the understanding of online human-human communication. It will enable more people to access social deliberative tools, promote interest in discussion among more people and improve the quality of on-line disputes as well as collaborations. The project lays the groundwork for more intelligent communication in online communities, creates new understandings of the complexities of collaboration and produces new modes of synergistic online discussions.

DESCRIPTION (provided by applicant): Natural products have played pivotal roles in neuropharmacology due to their potent and selective targeting of specific biochemical pathways and receptors, and are highly useful as probe substances and therapeutic leads. Marine cyanobacteria are exceptionally rich in diverse natural product structures, many of which are toxic or have other biological properties. We propose to continue our productive collaboration between a natural products chemist (Gerwick) and a neuropharmacologist (Murray), expanding on our previous investigations of these life forms for their new and biologically-insightful neuroactive compounds. Thus, we have the long range goals of 1) developing new compounds to serve as novel tools for pharmacology and cell biology, 2) describing new putative environmental toxins so that appropriate actions can be taken should outbreaks occur, and 3) development of neuroactive substances as potential therapeutic lead compounds, especially in the treatment of stroke-induced brain injury. To accomplish these goals we have the following four specific aims: 1) to collect 250 samples of cyanobacteria and algae, and produce high quality focused fraction libraries for screening in assays designed to detect neuroactive natural products, 2) to evaluate the above diverse extracts using high throughput spontaneous Ca2+ oscillation and Na+ influx assays in cerebrocortical neurons, 3) to use innovative and accelerated methods to isolate and structurally characterize new neuroactive substances from marine cyanobacteria testing positively in the screening assays, featuring nanoscale NMR and MSn methods, 4) to further define the molecular pharmacology of several cyanobacterial toxins discovered during prior support. Additionally, to evaluate the influence of newly discovered cyanobacterial ligands on neurite outgrowth, spinogenesis and synaptogenesis in neocortical neurons. Select compounds active in these in vitro assays will be advanced into a mouse model for focal stroke. This will require the production of additional supplies or analogs of these newly discovered compounds, including radioisotope-labeled analogs to be used in radioligand binding and distribution assays. Completion of these aims will increase our knowledge of the unique and neuroactive natural products produced by marine cyanobacteria and algae. The past two cycles of support for this collaborative program have been highly productive, and we now have a mature, well functioning, and highly effective program. We continue to refine our approaches and thinking as applied to the discovery and utility of novel marine neuroactive substances, and this leads us in new research directions for the proposed coming grant period, such as the application of voltage-gated sodium channel activators that promote neurite outgrowth in neocortical neurons to the potential treatment of stroke-induced brain injury.

The Cyberlearning and Future Learning Technologies Program funds efforts that support envisioning the future of learning technologies and advance what we know about how people learn in technology-rich environments. Integration (INT) projects refine and study emerging genres of learning technologies that have already undergone several years of iterative refinement in the context of rigorous research on how people learn with such technologies; INT projects contribute to our understanding of how the prototype tools might generalize to a larger category of learning technologies. This INT project integrates prior work from two well-developed NSF-sponsored projects on (i) advanced computer vision and (ii) affect detection in intelligent tutoring systems. The latter work in particular developed instruments to detect student emotion (interest, confusion, frustration and boredom) and showed that when a computer tutor responded to negative student affect, learning performance improved. The current project will expand this focus beyond emotion to attempt to also detect persistence, self-efficacy, and the trait called 'grit.' The project will measure the impact of these constructs on student learning and explore whether the grit trait (a persistent tendency towards sustained initiative and interest) can be improved and whether and how it depends on other recently experienced emotions. The technological innovation enabling this research into the genre of broadly affectively aware instruction is Smartutors, a tool that uses advanced computer vision techniques to view a student's gaze, hand gestures, head, and face to increase the "bandwidth" for automatically detecting their affect. One goal is to reorient students to more productive attitudes once waning attention is recognized.

This research team brings together a unique blend of leading interdisciplinary researchers in computer vision; adaptive education technology and computer science; mathematics education; learning companions; and meta-cognition, emotion, self-efficacy and motivation. Nine experiments will provide valuable data to extend and validate existing models of grit and emotion. In particular, the team will gather fine-grained data on grit, assess the impact of tutor interventions in real-time, and contribute thereby to a theory of grit. Visual data of student behavior will be integrated with advanced analytics of log data of students' actions based on the behavior of over 10,000 prior students (e.g., hint requests, topic mastery) to provide individualized guidance and tutor responses in a timely fashion. This will allow the researchers to measure the impact of interventions on student performance and attitude, and it will uncover how grit levels relate to emotion and what impact emotions and grit combined have on overall student initiative. By identifying interventions that are sensitive to individual differences, this research will refine theories of motivation and emotion and will reveal principles about how to respond to student grit and affect, especially when attention and persistence begin to wane. To ensure classroom success, the PIs will evaluate Smartutors with 1,600 students and explore its transferability by testing it in a more difficult mathematics domain with older students.