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2007

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Articles 1651 - 1680 of 6758

Full-Text Articles in Physical Sciences and Mathematics

Crystal And Electronic Structures Of The Complex Hydride Li₄Bn₃H₁₀, Jinbo Yang, X. J. Wang, Qingsheng Cai, William B. Yelon, William Joseph James Aug 2007

Crystal And Electronic Structures Of The Complex Hydride Li₄Bn₃H₁₀, Jinbo Yang, X. J. Wang, Qingsheng Cai, William B. Yelon, William Joseph James

Physics Faculty Research & Creative Works

The crystal structure of Li4BN3H10 was investigated using powder neutron diffraction with high sensitivity. The compound crystallizes in the cubic space group 213 with lattice parameters a=10.645 19(52) Å with an ordered arrangement of [NH2]−1 and [BH4]−1 anions in a molar ratio of 3:1. The bond lengths between the nearest nitrogen and hydrogen atoms are 1.04(4) and 1.14(4) Å. The bond angle between H(1)-N-H(2) is about 126(6)°, while those between H(3)-B-H(3) and H(3)-B-H(4) are about 109(6)°-110(7)°. There are three different Li sites surrounded by [NH2]−1 and [BH4]−1 anions in distorted tetrahedral configurations. The Li(3)-B and Li(3)-N bond distances are about …

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On The Simplification Of Certain Q-Multisums, Andrew Sills Aug 2007

On The Simplification Of Certain Q-Multisums, Andrew Sills

Department of Mathematical Sciences Faculty Publications

Some examples of naturally arising multisum q-series which turn out to have representations as fermionic single sums are presented. The resulting identities are proved using transformation formulas from the theory of basic hypergeometric series.

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Gis Data: Lynnhaven River Virginia Beach, Virginia Shoreline Inventory Report, Marcia Berman, Harry Berquist, Sharon Killeen, Karinna Nunez, Tamia Rudnicky, Daniel E. Schatt, Karen Reay, David Weiss Aug 2007

Gis Data: Lynnhaven River Virginia Beach, Virginia Shoreline Inventory Report, Marcia Berman, Harry Berquist, Sharon Killeen, Karinna Nunez, Tamia Rudnicky, Daniel E. Schatt, Karen Reay, David Weiss

Data

The data contained within the Shoreline Inventory is based on a three-tiered shoreline assessment approach. The assessment characterizes conditions that are observed from a small boat navigating along the shoreline. Hand-held GPS units are used to log features. The three tiered shoreline assessment approach reports conditions in three regions: 1) the immediate riparian zone, evaluated for land use; 2) the bank, evaluated for height, stability, cover and natural protection; and 3) the shoreline, describing the presence of shoreline structures for shore protection and recreational purposes. Three GIS coverages are generated. The lynn_lubc coverage contains features related to the land use …

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Upper Limits On Gravitational Wave Emission From 78 Radio Pulsars, B. P. Abbott, R. Abbott, Mario C. Diaz, Soumya Mohanty, Soma Mukherjee, Cristina V. Torres Aug 2007

Upper Limits On Gravitational Wave Emission From 78 Radio Pulsars, B. P. Abbott, R. Abbott, Mario C. Diaz, Soumya Mohanty, Soma Mukherjee, Cristina V. Torres

Physics and Astronomy Faculty Publications and Presentations

We present upper limits on the gravitational wave emission from 78 radio pulsars based on data from the third and fourth science runs of the LIGO and GEO 600 gravitational wave detectors. The data from both runs have been combined coherently to maximize sensitivity. For the first time, pulsars within binary (or multiple) systems have been included in the search by taking into account the signal modulation due to their orbits. Our upper limits are therefore the first measured for 56 of these pulsars. For the remaining 22, our results improve on previous upper limits by up to a factor …

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Nitrogen Heterocyclic Compounds As Receptors In Nanosensors For Nerve Gas Agent Analogs, Swapna Katram Aug 2007

Nitrogen Heterocyclic Compounds As Receptors In Nanosensors For Nerve Gas Agent Analogs, Swapna Katram

Masters Theses

The research is focused on developing nanosensors consisting of different components that are chemically linked, namely, nanoparticle, fluorescent monomer, and receptor (NMR sensors) and nanoparticle, monomer, nanomolecule, and receptor (NMNR sensors) for the sensitive and selective detection of nerve gas agents. These sensors detect the target toxins by fluorescence change which is amplified by signal transduction. Model nerve gas toxins (DCP) and (DMMP) and HCl were employed as analytes, and the nitrogen heterocyclic compounds, 5-aminoindazole and dipyrido[3,2-a:2',3'-c]phenazine (dppz) as receptors in the NMR and NNMR nanosensors. The monomers were (E)-4-(4- formylstyryl) benzoic acid (NMR sensor) and 2-mercaptosuccinic acid (NNMR sensor). …

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Infinitely Many Radial Solutions For A Sub-Super Critical Dirichlet Boundary Value Problem In A Ball, Alfonso Castro, John Kwon, Chee Meng Tan '07 Aug 2007

Infinitely Many Radial Solutions For A Sub-Super Critical Dirichlet Boundary Value Problem In A Ball, Alfonso Castro, John Kwon, Chee Meng Tan '07

All HMC Faculty Publications and Research

We prove the existence of infinitely many solutions to a semilinear Dirichlet boundary value problem in a ball for a nonlinearity g(u) that grows subcritically for u positive and supercritically for u negative.

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A Fixed Point Theorem For The Infinite-Dimensional Simplex, Douglas Rizzolo '08, Francis E. Su Aug 2007

A Fixed Point Theorem For The Infinite-Dimensional Simplex, Douglas Rizzolo '08, Francis E. Su

All HMC Faculty Publications and Research

We define the infinite-dimensional simplex to be the closure of the convex hull of the standard basis vectors in R∞, and prove that this space has the fixed point property: any continuous function from the space into itself has a fixed point. Our proof is constructive, in the sense that it can be used to find an approximate fixed point; the proof relies on elementary analysis and Sperner's lemma. The fixed point theorem is shown to imply Schauder's fixed point theorem on infinite-dimensional compact convex subsets of normed spaces.

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Molecular Anion Spectroscopy And Stability, Jeffrey Daniel Steill Aug 2007

Molecular Anion Spectroscopy And Stability, Jeffrey Daniel Steill

Doctoral Dissertations

A detailed and thorough computational investigation of the SF 6 anion is undertaken, with additional calculations of other stable SF n anions. The calculations are used to in- terpret recent infrared multi-photon dissociation (IRMPD) experiments of SF 6 and SF 5 anions done with the FELIX free electron tunable infrared laser in the spectral range of 450-850 cm-1. The vibrational spectroscopy of negative molecular ions is crucial towards understanding the dynamics of electron transfer processes, as well as providing experimental validation for computational models of molecular bonding in anions. Many molecular negative ions have been shown to exhibit …

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Assessment Of Undiscovered Oil And Gas Resources In Tertiary Strata Of The Gulf Coast, 2007 Aug 2007

Assessment Of Undiscovered Oil And Gas Resources In Tertiary Strata Of The Gulf Coast, 2007

United States Geological Survey: Publications

Using a geology-based assessment methodology, the U.S. Geological Survey estimated a mean of 113.7 trillion cubic feet of undiscovered natural gas, a mean of 690 million barrels of undiscovered oil, and a mean of 3.7 billion barrels of undiscovered natural gas liquids in onshore lands and State waters of the Gulf Coast.

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Csi Revisited: The Science Of Forensic Dna Analysis, Michael L. Raymer Aug 2007

Csi Revisited: The Science Of Forensic Dna Analysis, Michael L. Raymer

Kno.e.sis Publications

No abstract provided.

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Relationship Web: Spinning The Semantic Web From Trailblazing To Complex Hypothesis Evaluation, Amit P. Sheth Aug 2007

Relationship Web: Spinning The Semantic Web From Trailblazing To Complex Hypothesis Evaluation, Amit P. Sheth

Kno.e.sis Publications

No abstract provided.

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Trailblazing, Complex Hypothesis Evaluation, Abductive Reasoning And Semantic Web - Exploring Possible Synergy, Amit P. Sheth Aug 2007

Trailblazing, Complex Hypothesis Evaluation, Abductive Reasoning And Semantic Web - Exploring Possible Synergy, Amit P. Sheth

Kno.e.sis Publications

No abstract provided.

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Fault Tolerant Firewall Sandwiches, Stephen M. Goddard Aug 2007

Fault Tolerant Firewall Sandwiches, Stephen M. Goddard

School of Computing: Faculty Publications

Firewall sandwich configurations having improved levels of system availability as well as an application-space implementation of a firewall load balancer (FLB) which provides greater operational flexibility while reducing the need for custom hardware and/or operating system software. Also disclosed is a firewall capable of functionally replacing an FLB upon detecting a failure therein.

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Space Adaptation: Privacy-Preserving Multiparty Collaborative Mining With Geometric Perturbation, Keke Chen, Ling Liu Aug 2007

Space Adaptation: Privacy-Preserving Multiparty Collaborative Mining With Geometric Perturbation, Keke Chen, Ling Liu

Kno.e.sis Publications

The service-oriented infrastructure has become popular for collaboratively mining data distributed over organizations [3], where the participants are the data providers who submit their perturbed datasets to the designated data mining service provider (the data miner) for mining commonly interested models.

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Thermally Driven Defect Formation And Blocking Layers At Metal-Zno Interfaces, H. L. Mosbacker, C. Zgrabik, M. J. Hetzer, A. Swain, David C. Look, G. Cantwell, J. Zhang, J. J. Song, L. J. Brillson Aug 2007

Thermally Driven Defect Formation And Blocking Layers At Metal-Zno Interfaces, H. L. Mosbacker, C. Zgrabik, M. J. Hetzer, A. Swain, David C. Look, G. Cantwell, J. Zhang, J. J. Song, L. J. Brillson

Physics Faculty Publications

The authors used depth-resolved cathodoluminescence spectroscopy and current-voltage measurements to probe the temperature-dependent formation of native point defects and reaction layers at metal-ZnO interfaces and their effect on transport properties. These results identify characteristic defect emissions corresponding to metal-Zn alloy versus oxide formation. Au alloys with Zn above its eutectic temperature, while Ta forms oxide blocking layers that reduce current by orders of magnitude at intermediate temperatures. Defects generated at higher temperatures and/or with higher initial defect densities for all interfaces produce Ohmic contacts. These reactions and defect formation with annealing reveal a thermodynamic control of blocking versus Ohmic contacts.

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Wireless Passive Surface Acoustic Wave (Saw) Sensing System, Sridevi Krishnamurthy Aug 2007

Wireless Passive Surface Acoustic Wave (Saw) Sensing System, Sridevi Krishnamurthy

Dissertations

Due to their small size and ruggedness, Surface Acoustic Wave (SAW) devices have been widely used as part of wireless sensing or identification system especially in inaccessible and inhospitable environments. In addition, SAW devices find widespread applications as filters in communication systems and also as physical, chemical and bio-sensors and ID tags. The passive wireless SAW sensing system mainly consists of a passive SAW sensor and an interrogation unit which sends a burst signal to the SAW sensor and processes the sensor response. Theobjectives of this work were designing, prototyping and fabricating the interrogation unit on a PCB and also …

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Adaptation To High Temperatures Through Macromolecular Dynamics By Neutron Scattering, M. Tehei, G. Zaccai Aug 2007

Adaptation To High Temperatures Through Macromolecular Dynamics By Neutron Scattering, M. Tehei, G. Zaccai

Faculty of Science - Papers (Archive)

Work on the relationship between hyperthermophile protein dynamics, stability and activity is reviewed. Neutron spectroscopy has been applied to measure and compare the macromolecular dynamics of various hyperthermophilic and mesophilic proteins, under different conditions. First, molecular dynamics have been analyzed for the hyperthermophile malate dehydrogenase from Methanococcus jannaschii and a mesophilic homologue, the lactate dehydrogenase from Oryctolagus cunniculus (rabbit) muscle. The neutron scattering approach has provided independent measurements of the global flexibility and structural resilience of each protein, and it has been demonstrated that macromolecular dynamics represents one of the molecular mechanisms of thermoadaptation. The resilience was found to be …

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An Integrated Framework For Enhancing User Experience For Different Data Services In Multi-Rate Wireless Systems, Sourav Pal Aug 2007

An Integrated Framework For Enhancing User Experience For Different Data Services In Multi-Rate Wireless Systems, Sourav Pal

Computer Science and Engineering Dissertations

Technological advances in multi\--rate wireless systems have made wireless data services an intrinsic part of human life. An abundance of wireless devices, both in the wireless enabled home multimedia systems as well as in corporate offices, have trigerred an array of research in enhancing the wireless data services. The success and acceptance of these various rich data services Technological advances in multi\--rate wireless systems have made wireless data services an intrinsic part of human life. An abundance of wireless devices, both in the wireless enabled home multimedia systems as well as in corporate offices, have trigerred an array of research …

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A Scalable Approach For Survivable Virtual Topology Routing In Optical Wdm Networks, Ajay Todimala, Byrav Ramamurthy Aug 2007

A Scalable Approach For Survivable Virtual Topology Routing In Optical Wdm Networks, Ajay Todimala, Byrav Ramamurthy

School of Computing: Faculty Publications

The survivable virtual topology routing problem is to route a virtual topology graph on a optical fiber physical topology such that the virtual topology remains connected when failures occur in the physical topology. In this work we study the problem of survivable virtual topology routing under single node/SRLG (Shared Risk Link Group) failure model. We prove that the survivable virtual topology routing problem under node/SRLG failures is NP-complete. We present an improved integer linear programming (ILP) formulation for computing the survivable routing of a virtual topology graph. However, ILP is not scalable when the network size scales more than a …

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Characterizing Sparse Graphs By Map Decompositions, Ruth Haas, Audrey Lee, Ileana Streinu, Louis Theran Aug 2007

Characterizing Sparse Graphs By Map Decompositions, Ruth Haas, Audrey Lee, Ileana Streinu, Louis Theran

Mathematics Sciences: Faculty Publications

A map is a graph that admits an orientation of its edges so that each vertex has out-degree exactly 1. We characterize graphs which admit a decomposition into k edge-disjoint maps after: (1) the addition of any ℓ edges; (2) the addition of some ℓ edges. These graphs are identified with classes of sparse graphs; the results are also given in matroidal terms.

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The Whitehead Link On The Cubic Lattice, Elizabeth Haynes Aug 2007

The Whitehead Link On The Cubic Lattice, Elizabeth Haynes

Masters Theses & Specialist Projects

The cubic lattice is a graph in Â3 where the vertices are points with integer coordinates and edges are unit length line segments parallel to the x-, y-, or z-axis. A step is a line segment that connects one vertex to a neighboring vertex one unit away in the x-, y-, or z-direction. This thesis will show that the Whitehead Link needs at least 34 steps to be embedded on the cubic lattice.

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Electron And Hole Dynamics Of Inas∕Gaasinas∕Gaas Quantum Dot Semiconductor Optical Amplifiers, I. O'Driscoll, T. Piwonski, C. F. Schleussner, J. Houlihan, G. Huyet, R. J. Manning Aug 2007

Electron And Hole Dynamics Of Inas∕Gaasinas∕Gaas Quantum Dot Semiconductor Optical Amplifiers, I. O'Driscoll, T. Piwonski, C. F. Schleussner, J. Houlihan, G. Huyet, R. J. Manning

Physical Sciences Publications

Single-color and two-color pump-probe measurements are used to analyze carrier dynamics in InAs∕GaAs quantum dot amplifiers. The study reveals that hole recovery and intradot electron relaxation occur on a picosecond time scale, while the electron capture time is on the order of 10ps. A longer time scale of hundreds of picoseconds is associated with carrier recovery in the wetting layer, similar to that observed in quantum well semiconductor amplifiers.

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A Framework For Improving The Performance Of Application Servers In Next Generation Networks (Ngns), Sumantra R. Kundu Aug 2007

A Framework For Improving The Performance Of Application Servers In Next Generation Networks (Ngns), Sumantra R. Kundu

Computer Science and Engineering Dissertations

Next generation networks (NGNs) such as IP Multimedia Subsystem (IMS) are completely built on the Internet Protocol (IP) suite. This has made IP the de facto standard for data networking, voice over IP (VoIP), and media rich applications such as streaming multimedia, ringtones, multi-player gaming, and high-definition video conferencing for remote interaction. A primary feature of such converged networks is that they use the same IP-based network for simultaneously delivering voice, video, and data. Such services are provided on application servers built using industry standard Advanced Telecom Computing Architecture (ATCA) based blade computing units with various flavors of commodity open …

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Characteristics Of Short-Period Wavelike Features Near 87 Km Altitude From Airglow And Lidar Observations Over Maui, J. H. Hecht, A. Z. Liu, R. L. Walterscheid, S. J. Franke, R. J. Rudy, Michael J. Taylor, Pierre-Dominique Pautet Aug 2007

Characteristics Of Short-Period Wavelike Features Near 87 Km Altitude From Airglow And Lidar Observations Over Maui, J. H. Hecht, A. Z. Liu, R. L. Walterscheid, S. J. Franke, R. J. Rudy, Michael J. Taylor, Pierre-Dominique Pautet

All Physics Faculty Publications

Small-scale (less than 15 km horizontal wavelength) wavelike structures known as ripples are a common occurrence in OH airglow images. Recent case studies attribute their origin to the presence of either convective or dynamical instabilities. However, little is known about their frequency of occurrence and period. The Maui-MALT Observatory, located at Mt. Haleakala, is instrumented with a Na wind/temperature lidar, which allows the determination of whether the atmosphere is dynamically or convectively unstable, and a fast OH airglow camera which takes images every 3 s with a sensitivity high enough to see the ripples. This study reports on 2 months …

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Predictors Of Female Sexual Dysfunction, Julie M. Merrell Aug 2007

Predictors Of Female Sexual Dysfunction, Julie M. Merrell

Loma Linda University Electronic Theses, Dissertations & Projects

Tiefer, Hall, and Tavris (2002) described factors comprising four categories of female sexual dysfunction. They suggested that unique factors need to be examined to understand sexual dysfunction in women. Socio-cultural, political, or economic factors, partner and relationship factors, psychological factors, and medical factors described as aspects of women’s lives that can be the source of sexual dysfunction. The current study examined indicators of the above factors-body shame, relationship satisfaction, sexual self-schema, positive and negative affect, and overall health-as predictors of female sexual dysfunction. The hypotheses were: Body shame and negative affect will be negatively associated with sexual function; and relationship …

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Species-Specific Visitation And Removal Of Baits For Delivery Of Pharmaceuticals To Feral Swine, Tyler A. Campbell, David B. Long Aug 2007

Species-Specific Visitation And Removal Of Baits For Delivery Of Pharmaceuticals To Feral Swine, Tyler A. Campbell, David B. Long

United States Department of Agriculture Wildlife Services: Staff Publications

Within the domestic swine industry there is growing trepidation about the role feral swine (Sus scrofa) play in the maintenance and transmission of important swine diseases. Innovative disease management tools for feral swine are needed. We used field trials conducted in southern Texas from February to March 2006 to compare species-specific visitation and removal rates of fish-flavored and vegetable-flavored baits with and without commercially available raccoon (Procyon lotor/) repellent (trial 1) and removal rates of baits deployed in a systematic and cluster arrangement (trial 2). During trial 1, 1) cumulative bait removal rates after four nights …

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Transient And Periodic Solution To The Time-Inhomogeneous Quasi-Birth Death Process, Barbara Haas Margolius Aug 2007

Transient And Periodic Solution To The Time-Inhomogeneous Quasi-Birth Death Process, Barbara Haas Margolius

Mathematics and Statistics Faculty Publications

We derive the transient distribution and periodic family of asymptotic distributions and the transient and periodic moments for the quasi-birth-and-death processes with time-varying periodic rates. The distributions and moments are given in terms of integral equations involving the related random-walk process. The method is a straight-forward application of generating functions.

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Betti Numbers And Degree Bounds For Some Linked Zero-Schemes, Leah Gold, Hal Schenck, Hema Srinivasan Aug 2007

Betti Numbers And Degree Bounds For Some Linked Zero-Schemes, Leah Gold, Hal Schenck, Hema Srinivasan

Mathematics and Statistics Faculty Publications

In [J. Herzog, H. Srinivasan, Bounds for multiplicities, Trans. Amer. Math. Soc. 350 (1998) 2879–2902], Herzog and Srinivasan study the relationship between the graded Betti numbers of a homogeneous ideal II in a polynomial ring RR and the degree of II. For certain classes of ideals, they prove a bound on the degree in terms of the largest and smallest Betti numbers, generalizing results of Huneke and Miller in [C. Huneke, M. Miller, A note on the multiplicity of Cohen–Macaulay algebras with pure resolutions, Canad. J. Math. 37 (1985) 1149–1162]. The bound is conjectured to hold in general; we study …

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The John Muir Newsletter, Fall 2007, The John Muir Center For Environmental Studies Aug 2007

The John Muir Newsletter, Fall 2007, The John Muir Center For Environmental Studies

Muir Center Newsletters (1981-2015)

John Muir Hanna: A Biography Bill Hanna, Napa, California FAMILY John Muir Hanna was born on March 15, 1909 in Oakland to Wanda Muir and Thomas Rae Hanna. He was the second child of six. His older brother was Strent (Strentzel) who was born in 1907. His younger siblings were Richard, Robert, Jean, and Ross. His grandfather was the naturalist and preservationist John Muir and his grandmother was Louie Strentzel Muir whose parents had settled in Martinez in 1853. John's mother, Annie Wanda Muir, was the elder daughter of John Muir and Louie Strentzel. She and her sister, Helen, were …

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The Effect Of Chloramphenicol On Bb88 Murine Erythroleukemia Cells, Peter K. W. Harris Aug 2007

The Effect Of Chloramphenicol On Bb88 Murine Erythroleukemia Cells, Peter K. W. Harris

Dissertations

DNA microarrays can be used to measure genome-wide transcript levels. These measurements may be useful in understanding cellular changes induced by a chemical agent. In this study, Affymetrix microarray technology has been used to study the effects of chloramphenicol, an antibiotic that inhibits bacterial and mitochondrial protein synthesis, on the transcription profile in mammalian cells. Transcript levels in BB88 murine erythroleukemia cells treated with 50 micromolar ( mu M) chloramphenicol, a concentration shown to inhibit BB88 proliferation, are measured. Using total RNA from treated cells, biotin-labeled cRNA was prepared and hybridized to Affymetrix U74Av2 microarrays. From these hybridizations, expression levels …

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