Physical Sciences and Mathematics Commons^™

Compartmentalization Of Prion Isoforms Within The Reproductive Tract Of The Ram, Heath W. Ecroyd, Pierre Sarradin, Jean-Louis Dacheux, Jean-Luc Gatti

Faculty of Science - Papers (Archive)

Cellular prion protein (Prp(C)) is a glycoprotein usually associated with membranes via its glycosylphosphatidylinositol (GPI) anchor. The trans-conformational form of this protein (Prp(SC)) is the suggested agent responsible for transmissible neurodegenerative spongiform encephalopathies. This protein has been shown on sperm and in the reproductive fluids of males. Antibodies directed against the C-terminal sequence near the GPI-anchor site, an N-terminal sequence, and against the whole protein showed that the Prp isoforms were compartmentalized within the reproductive tract of the ram. Immunoblotting with the three antibodies showed that the complete protein and both N- and C-terminally truncated and glycosylated isoforms are present …

Analysis Of The Mechanism By Which Calcium Negatively Regulates The Tyrosine Phosphorylation Cascade Associated With Sperm Capacitation, Mark Baker, Louise Hethrington, Heath W. Ecroyd, Shaun D. Roman, Robert J. Aitken

Faculty of Science - Papers (Archive)

The capacitation of mammalian spermatozoa involves the activation of a cAMP-mediated signal transduction pathway that drives tyrosine phosphorylation via mechanisms that are unique to this cell type. Controversy surrounds the impact of extracellular calcium on this process, with positive and negative effects being recorded in independent publications. We clearly demonstrate that the presence of calcium in the external medium decreases tyrosine phosphorylation in both human and mouse spermatozoa. Under these conditions, a rise in intracellular pH was recorded, however, this event was not responsible for the observed changes in phosphotyrosine expression. Rather, the impact of calcium on tyrosine phosphorylation in …

Arts And Sciences Newsletter, Volume 7, Issue 3, College Of Arts & Sciences

Arts and Sciences Newsletters

No abstract provided.

Charge-On-Spring Polarizable Water Models Revisited: From Water Clusters To Liquid Water To Ice, Haibo Yu, Wilfred Van Gunsteren

Faculty of Science - Papers (Archive)

The properties of two improved versions of charge-on-spring �COS� polarizable water models (COS/G2 and COS/G3) that explicitly include nonadditive polarization effects are reported. In COS models, the polarization is represented via a self-consistently induced dipole moment consisting of a pair of separated charges. A previous polarizable water model (COS/B2), upon which the improved versions are based, was developed by Yu, Hansson, and van Gunsteren �J. Chem. Phys. 118, 221 �2003��. To improve the COS/B2 model, which overestimated the dielectric permittivity, one additional virtual atomic site was used to reproduce the water monomer quadrupole moments besides the water monomer dipole moment …

On The Transferability Of The Spcal Water Model To Biomolecular Simulation, Alice Glaettli, Chris Oostenbrink, Xavier Daura, Daan Geerke, Haibo Yu, Wilfred Van Gunsteren

Faculty of Science - Papers (Archive)

We investigated the performance of the recently developed SPC/L model for liquid water, as a pure liquid, in binary mixtures with DMSO, and as a solvent model in a peptide folding simulation. Additionally, in order to test the compatibility with the GROMOS biomolecular force field, free energies of hydration of a set of representative compounds were computed. The results are compared to those for the well established SPC water model, which is generally used as a solvent model in conjunction with the GROMOS force field already for more than two decades. It turns out that as a pure liquid and …

The Development Of Signal Transduction Pathways During Epididymal Maturation Is Calcium Dependent, Heath W. Ecroyd, Kelly Asquith, Russell C. Jones, Robert J. Aitken

Faculty of Science - Papers (Archive)

Capacitation has been correlated with the activation of a cAMP-PKA-dependent signaling pathway leading to protein tyrosine phosphorylation. The ability to exhibit this response to cAMP matures during epididymal maturation in concert with the ability of the sperrnatozoa to capacitate. In this study, we have addressed the mechanisms by which spermatozoa gain the potential to activate this signaling pathway during epididymal maturation. In a modified Tyrode's medium containing 1.7 mM calcium, caput spermatozoa had significantly higher [Ca2+](i) than caudal cells and could not tyrosine phosphorylate in response to cAMP. However, in calcium-depleted medium both caput and caudal cells could exhibit a …

Processes Controlling Metal Transport And Retention As Metal-Contaminated Groundwaters Efflux Through Estuarine Sediments, Stuart L. Simpson, Edward J. Maher, Dianne F. Jolley

Faculty of Science - Papers (Archive)

Factors affecting the transport and retention of Cd, Cr, Cu, Ni, Pb and Zn in acidic groundwaters as they pass through estuarine sediments were investigated using column experiments. Acidic groundwaters caused the rapid dissolution of iron sulfide (AVS) and other iron and manganese phases from sediments that are important for metal binding and buffering. Metal breakthrough to overlying water occurred in the order of Ni>Zn>Cd>>Cu>>Cr/Pb. Metal transport increased as the sediment permeability increased, reflecting the low resistance to flow caused by larger sand-sized particles and the decreased abundance of metal adsorption sites on these materials. Metal …

Protecting Group Effects On The Efficiency Of The Ruthenium-Catalyzed Alder-Ene Reaction, Joseph Hartley, Stephen G. Pyne

Faculty of Science - Papers (Archive)

The efficiency of the ruthenium-catalysed Alder-ene reaction of hydroxy alkenes depends heavily on the nature of the O-protecting groups employed as well as the length of the carbon spacer between the hydroxy and alkene group.

Analysis Of Social Aspects Of Migrant Labourers Living With Hiv/Aids Using Fuzzy Theory And Neutrosophic Cognitive Maps, Florentin Smarandache, W.B. Vasantha Kandasamy

Branch Mathematics and Statistics Faculty and Staff Publications

Neutrosophic logic grew as an alternative to the existing topics and it represents a mathematical model of uncertainty, vagueness, ambiguity, imprecision, undefined-ness, unknown, incompleteness, inconsistency, redundancy and contradiction. Despite various attempts to reorient logic, there has remained an essential need for an alternative system that could infuse into itself a representation of the real world. Out of this need arose the system of neutrosophy and its connected logic, neutrosophic logic. This new logic, which allows also the concept of indeterminacy to play a role in any real-world problem, was introduced first by one of the authors Florentin Smarandache. In this …

Paranthropus Paleobiology, Paul J. Constantino, Bernard A. Wood

Biological Sciences Faculty Research

No abstract provided.

Java-Based Digital Library Portal For Geography Education, Zehua Liu, Hai Yuan, Ee Peng Lim, Ming Yin, Dion Hoe-Lian Goh, Yin-Leng Theng, Wee-Keong Ng

Research Collection School Of Computing and Information Systems

G-Portal is a Java-based digital library system for managing the metadata of geography related resources on the Web. In addition to providing a flexible repository subsystem to accommodate metadata of different formats using XML and XML Schemas, G-Portal organizes metadata into projects and layers, and supports an integrated and synchronized classification and map-based interfaces over the stored metadata. G-Portal also includes a classification subsystem that creates category structures and classifies metadata resources into categories based on user-specified classification schemas. Furthermore, G-Portal users can annotate resources and make their annotations available to others. In this paper, we describe the design and …

On The Decidability Of The Termination Problem Of Active Database Systems, James Bailey, Guozhu Dong, K. Rammamohanarao

Kno.e.sis Publications

Active database systems enhance the functionality of traditional databases through the use of active rules or ‘triggers’. One of the principal analysis questions for such systems is that of termination—is it possible for the rules to recursively activate one another indefinitely, given an initial triggering event. In this paper, we study the decidability of the termination problem, our aim being to delimit the boundary between the decidable and the undecidable. We present results for two broad types of variations, variations in rule syntax and variations in meta level features. Within each of these, we identify members close to the …

Semantic Integration Of Glycomics Data And Information, William S. York, Amit P. Sheth, Krzysztof J. Kochut, John A. Miller, Christopher Thomas, Karthik Gomadam, X. Yi, Meenakshi Nagarajan

Kno.e.sis Publications

No abstract provided.

Discovering And Ranking Semantic Associations Over A Large Rdf Metabase, Christian Halaschek-Wiener, Boanerges Aleman-Meza, I. Budak Arpinar, Amit P. Sheth

Kno.e.sis Publications

Information retrieval over semantic metadata has recently received a great amount of interest in both industry and academia. In particular, discovering complex and meaningful relationships among this data is becoming an active research topic. Just as ranking of documents is a critical component of today's search engines, the ranking of relationships will be essential in tomorrow's semantic analytics engines. Building upon our recent work on specifying these semantic relationships, which we refer to as Semantic Associations, we demonstrate a system where these associations are discovered among a large semantic metabase represented in RDF. Additionally we employ ranking techniques to provide …

Exploiting Syntactic, Semantic And Lexical Regularities In Language Modeling Via Directed Markov Random Fields, Shaojun Wang, Shaomin Wang, Russell Greiner, Dale Schuurmans, Li Cheng

Kno.e.sis Publications

No abstract provided.

Semantic Visualization: Interfaces For Exploring And Exploiting Ontology, Knowledgebase, Heterogeneous Content And Complex Relationships, Amit P. Sheth, David Avant

Kno.e.sis Publications

Technology platforms and products for ontology-driven process of semantic applications that serve both Enterprise wide and pan-Web needs are both available and being deployed. Similar to the development of enterprise software applications, the creation of an ontology driven semantic application can be described as a set of distinct phases that compose a lifecycle. From conception to deployment, these phases involve human interaction with a broad variety of information, identified as heterogeneous data, metadata, knowledge and ontology. Based on experience spanning academic research at the LSDIS lab through deployed commercial semantic applications based on Semagix Freedom, this paper provides examples of …

Early Work In Database Research On Schema Mapping/Merging/Transformation, Semantic Heterogeneity, And Use Of Ontology And Description Logics For Schematic And Semantic Integration, Amit P. Sheth

Kno.e.sis Publications

No abstract provided.

Capturing The Dialectic Between Principles And Cases, Kevin D. Ashley

Articles

Theorists in ethics and law posit a dialectical relationship between principles and cases; abstract principles both inform and are informed by the decisions of specific cases. Until recently, however, it has not been possible to investigate or confirm this relationship empirically. This work involves a systematic study of a set of ethics cases written by a professional association's board of ethical review. Like judges, the board explains its decisions in opinions. It applies normative standards, namely principles from a code of ethics, and cites past cases. We hypothesized that the board's explanations of its decisions elaborated upon the meaning and …

Sources Of Ancient Maize Found In Chacoan Great Houses, Larry Benson

United States Geological Survey: Staff Publications

Between the 9th and 12th centuries A.D., Chaco Canyon, located near the middle of the high-desert San Juan Basin of north-central New Mexico (fig. 1), was the focus of an unprecedented construction effort by pre-Columbian Native Americans. It has been estimated that from 2,000 to 6,000 people occupied Chaco Canyon during its heyday (Windes, 1984; Drager, 1976). One indication of Chaco’s regional importance is a network of roads that linked Chaco Canyon with other great houses and communities spread throughout a region covering at least 60,000 km2 (fig. 2). At the height of its cultural florescence in the 11th century, …

Deviance Information Criterion For Comparing Stochastic Volatility Models, Andreas Berg, Renate Meyer, Jun Yu

Research Collection School Of Economics

Bayesian methods have been efficient in estimating parameters of stochastic volatility models for analyzing financial time series. Recent advances made it possible to fit stochastic volatility models of increasing complexity, including covariates, leverage effects, jump components, and heavy-tailed distributions. However, a formal model comparison via Bayes factors remains difficult. The main objective of this article is to demonstrate that model selection is more easily performed using the deviance information criterion (DIC). It combines a Bayesian measure of fit with a measure of model complexity. We illustrate the performance of DIC in discriminating between various different stochastic volatility models using simulated …

Coastal Training Strategy For The Ohio Lake Erie Basin, Claudette Robey, Kevin O'Brien, Kirstin S. Toth

All Maxine Goodman Levin School of Urban Affairs Publications

An analysis of the market for coastal resources management training in Ohio’s Lake Erie basin identified the challenges faced by coastal decision-makers and the disparities currently existing within this market. The primary challenges identified were in the quality of instruction and in the types of training provided. Disparities indicated were with coordination, equipment and logistical factors, external and internal marketing and promotional assistance, funding, personnel and staff assistance, and legislative and regulatory concerns. These disparities are indications of opportunities to establish partnerships and collaborative networks to facilitate coordinated training initiatives; to re-examine and develop course content and locations to better …

Integrating Perception, Language And Problem Solving In A Cognitive Agent For A Mobile Robot., Deryle W. Lonsdale, D. Paul Benjamin, Damian M. Lyons

Faculty Publications

We are implementing a unified cognitive architecture for a mobile robot. Our goal is to endow a robot agent with the full range of cognitive abilities, including perception, use of natural language, learning and the ability to solve complex problems. The perspective of this work is that an architecture based on a unified theory of robot cognition has the best chance of attaining human-level performance.

This agent architecture is an integration of three theories: a theory of cognition embodied in the Soar system, the RS formal model of sensorimotor activity and an algebraic theory of decomposition and reformulation.

These three …

E-Rulemaking: Information Technology And The Regulatory Process: New Directions In Digital Government Research, Cary Coglianese

All Faculty Scholarship

Electronic rulemaking, or e-rulemaking, offers the potential to overcome some of the informational challenges associated with developing regulations. E-rulemaking refers to the use of digital technologies in the development and implementation of regulations. The use of these technologies may help streamline and improve regulatory management, such as by helping agency staff retrieve and analyze vast quantities of information from diverse sources. By taking better advantage of advances in digital technologies, agencies might also be able to increase the public's access to and involvement in rulemaking. Part I of this article details the rulemaking process, outlining the procedures agencies must currently …