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2000

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Full-Text Articles in Physical Sciences and Mathematics

Rnase L-Independent Specific 28s Rrna Cleavage In Murine Coronavirus-Infected Cells, Sangeeta Banerjee, Sungwhan An, Aimin Zhou, Robert H. Silverman, Shinji Makino Oct 2000

Rnase L-Independent Specific 28s Rrna Cleavage In Murine Coronavirus-Infected Cells, Sangeeta Banerjee, Sungwhan An, Aimin Zhou, Robert H. Silverman, Shinji Makino

Chemistry Faculty Publications

We characterized a novel 28S rRNA cleavage in cells infected with the murine coronavirus mouse hepatitis virus (MHV). The 28S rRNA cleavage occurred as early as 4 h postinfection (p.i.) in MHV-infected DBT cells, with the appearance of subsequent cleavage products and a decrease in the amount of intact 28S rRNA with increasing times of infection; almost all of the intact 28S rRNA disappeared by 24 h p.i. In contrast, no specific 18S rRNA cleavage was detected in infected cells. MHV-induced 28S rRNA cleavage was detected in all MHV-susceptible cell lines and all MHV strains tested. MHV replication was required …


Classically Forbidden Recurrences In The Photoabsorption Spectrum Of Lithium, V. Kondratovich, John B. Delos, Neal Spellmeyer, Daniel Kleppner Oct 2000

Classically Forbidden Recurrences In The Photoabsorption Spectrum Of Lithium, V. Kondratovich, John B. Delos, Neal Spellmeyer, Daniel Kleppner

Arts & Sciences Articles

We present data on the photoabsorption spectrum of lithium atoms in an electric field at energies between the saddle point of the Stark potential and below the field-free ionization threshold. The spectrum displays a sequence of sharp resonances and a sequence of broad ones. We find that the broad resonances arise from the classically forbidden reflection of waves above a dynamical potential barrier. The recurrence spectrum is also observed and it is dramatically affected by above-barrier reflections. We have developed a semiclassical theory that interprets the spectra using quasiclassical trajectories that undergo above-barrier reflection.


Circulation, Vol. 7, No. 3, Center For Coastal Physical Oceanography, Old Dominion University Oct 2000

Circulation, Vol. 7, No. 3, Center For Coastal Physical Oceanography, Old Dominion University

CCPO Circulation

Fall 2000 issue of CCPO Circulation featuring article "Worldwide Coastal Ocean Research at CCPO"


Ionization Of Hydrogen Atoms By Fast Electrons, Sindu P. Jones, Don H. Madison Oct 2000

Ionization Of Hydrogen Atoms By Fast Electrons, Sindu P. Jones, Don H. Madison

Physics Faculty Research & Creative Works

We study ionization of atomic hydrogen by fast electrons using asymptotically correct two-center wave functions to describe the scattering system both initially and finally. For the final state, we employ the well-known product wave function of Redmond, which treats all three two-body Coulomb interactions exactly, albeit independently. This "3C" wave function is the leading term of the exact scattering wave function, regardless of how slow the three particles are, if any two particles have large relative separation [Y.E. Kim and A.L. Zubarev, Phys. Rev. A 56, 521 (1997)]. Here we extend the analysis of Qiu et al. [Phys. Rev. A …


Dependence Among Spacings, Baha-Eldin Khaledi, Subhash C. Kochar Oct 2000

Dependence Among Spacings, Baha-Eldin Khaledi, Subhash C. Kochar

Mathematics and Statistics Faculty Publications and Presentations

In this paper, we study the dependence properties of spacings. It is proved that if X1,..., Xn are exchangeable random variables which are TP2 in pairs and their joint density is log-convex in each argument, then the spacings are MTP2 dependent. Next, we consider the case of independent but nonhomogeneous exponential random variables. It is shown that in this case, in general, the spacings are not MTP2 dependent. However, in the case of a single outlier when all except one parameters are equal, the spacings are shown to be MTP2 dependent and, hence, …


Sn/Ge(111) Surface Charge-Density-Wave Phase Transition, T. E. Kidd, T. Miller, M. Y. Chou, T.-C. Chiang Oct 2000

Sn/Ge(111) Surface Charge-Density-Wave Phase Transition, T. E. Kidd, T. Miller, M. Y. Chou, T.-C. Chiang

Faculty Publications

Angle-resolved photoemission has been utilized to study the surface electronic structure of 1/3 monolayer of Sn of Ge(111) in both the room-temperature (√3 × √3)R30° phase and the low-temprature (3 × 3) charge-density-wave phase. The results reveal a gap opening around the (3 × 3) Brillouin zone boundary, suggesting a Peierls-like transition despite the well-documented lack of Fermi nesting. A highly sensitive electronic response to doping by intrinsic surface defects is the cause for the unusual behaior, and a detailed calculation illustrates the origin of the (3 × 3) symmetry.


สถานการณ์ด้านมลพิษ ของประเทศไทย ปี 2543 Oct 2000

สถานการณ์ด้านมลพิษ ของประเทศไทย ปี 2543

Thai Environment

No abstract provided.


หลักเกณฑ์ในการกำหนดมาตรฐานคุณภาพอากาศ, นพภาพร พานิช Oct 2000

หลักเกณฑ์ในการกำหนดมาตรฐานคุณภาพอากาศ, นพภาพร พานิช

Thai Environment

No abstract provided.


การเก็บอากาศและการตรวจวิเคราะห์, นันทนา ชูฉัตร Oct 2000

การเก็บอากาศและการตรวจวิเคราะห์, นันทนา ชูฉัตร

Thai Environment

No abstract provided.


สัมภาษณ์ : รองศาสตราจารย์ ดร. นพภาพร พานิช อาจารย์ประจำสถาบันวิจัยสภาวะแวดล้อม จุฬาลงกรณ์มหาวิทยาลัย : ปัญหามลพิษทางอากาศกับการแก้ไขปัญหาของรัฐ, วลัยพร ศรีเพ็ญประภา, กรชนก รักษาเสรี Oct 2000

สัมภาษณ์ : รองศาสตราจารย์ ดร. นพภาพร พานิช อาจารย์ประจำสถาบันวิจัยสภาวะแวดล้อม จุฬาลงกรณ์มหาวิทยาลัย : ปัญหามลพิษทางอากาศกับการแก้ไขปัญหาของรัฐ, วลัยพร ศรีเพ็ญประภา, กรชนก รักษาเสรี

Thai Environment

No abstract provided.


วาระสุดท้ายของสารคลอโรฟลูออโรคาร์บอน (Cfcs) กับการทำลายโอโซนในชั้นบรรยากาศ, มานพ ติระรัตนสมโภช, ปิยวรรณ ปัญญาดี Oct 2000

วาระสุดท้ายของสารคลอโรฟลูออโรคาร์บอน (Cfcs) กับการทำลายโอโซนในชั้นบรรยากาศ, มานพ ติระรัตนสมโภช, ปิยวรรณ ปัญญาดี

Thai Environment

No abstract provided.


แนะนำโครงการของสถาบันวิจัยสภาวะแวดล้อม : โครงการติดตามตรวจด้านสิ่งแวดล้อมของการวางท่อก๊าซธรรมชาติ (Environmental Addit Of The Gas Pipe Construc), ธีรพล คังคะเกตุ Oct 2000

แนะนำโครงการของสถาบันวิจัยสภาวะแวดล้อม : โครงการติดตามตรวจด้านสิ่งแวดล้อมของการวางท่อก๊าซธรรมชาติ (Environmental Addit Of The Gas Pipe Construc), ธีรพล คังคะเกตุ

Thai Environment

No abstract provided.


สารกรดในบรรยากาศ มลพิษที่ไร้พรมแดน, ปทิตตา อินทร์ศร Oct 2000

สารกรดในบรรยากาศ มลพิษที่ไร้พรมแดน, ปทิตตา อินทร์ศร

Thai Environment

No abstract provided.


Structure And Phase Transitions Of The 6, 6-Cyclopropane Isomer Of C_ {61} H_ {2}, M. R. Stetzer, Paul A. Heiney, Peter W. Stephens, R. E. Dinnebier, Q. Zhu, Andrew R. Mcghie, Robert M. Strongin, B. M. Brandt, Amos B. Smith Iii Oct 2000

Structure And Phase Transitions Of The 6, 6-Cyclopropane Isomer Of C_ {61} H_ {2}, M. R. Stetzer, Paul A. Heiney, Peter W. Stephens, R. E. Dinnebier, Q. Zhu, Andrew R. Mcghie, Robert M. Strongin, B. M. Brandt, Amos B. Smith Iii

Chemistry Faculty Publications and Presentations

We have used x-ray powder diffraction and differential scanning calorimetry to study the crystalline structures and thermal behavior of the 6,6-cyclopropane isomer of C61H2. At room temperature, the C61H2 cyclopropane molecules, like those of the 6,5-annulene isomer and C60O epoxide, are orientationally disordered and crystallize on a face-centered-cubic lattice such that their methylene groups are statistically disordered among the octahedral voids. Unlike 6,5−C61H2 and C60O, the low-temperature structure is not Pa3¯, but rather a low-symmetry orthorhombic lattice in which a≈b


Resource Law Notes Newsletter, No. 50, Fall 2000, University Of Colorado Boulder. Natural Resources Law Center Oct 2000

Resource Law Notes Newsletter, No. 50, Fall 2000, University Of Colorado Boulder. Natural Resources Law Center

Resource Law Notes: The Newsletter of the Natural Resources Law Center (1984-2002)

No abstract provided.


Catchment Water Management: Guidelines For Those Considering Drainage For Waterlogging And Salinity Management, Department Of Agriculture And Food, Western Australia, Water And Rivers Commission, State Salinity Council Oct 2000

Catchment Water Management: Guidelines For Those Considering Drainage For Waterlogging And Salinity Management, Department Of Agriculture And Food, Western Australia, Water And Rivers Commission, State Salinity Council

Bulletins 4000 -

Landholder groups and government agencies are continuing to develop "best drainage practice" guidelines and these will increase our knowledge of drainage, and deep drainage in particular, as a management tool. The brochure does not provide all the answers, but is intended to provide some basic information to assist landholders who may be considering some form of water management or drainage systems.


A Formal Semantics For Spki, Jon Howell, David Kotz Oct 2000

A Formal Semantics For Spki, Jon Howell, David Kotz

Dartmouth Scholarship

We extend the logic and semantics of authorization due to Abadi, Lampson, et al. to support restricted delegation. Our formal model provides a simple interpretation for the variety of constructs in the Simple Public Key Infrastructure (SPKI), and lends intuition about possible extensions. We discuss both extensions that our semantics supports and extensions that it cautions against.


Fourier Transform Raman Spectroscopy For Process Control In The Petroleum Industry, Kent Lawson Wise Oct 2000

Fourier Transform Raman Spectroscopy For Process Control In The Petroleum Industry, Kent Lawson Wise

Chemistry & Biochemistry Theses & Dissertations

As early as 1950, Raman spectroscopy was proposed as a method to determine aromatics and olefins in hydrocarbon mixtures. Until recently, extensive use of Raman spectroscopy in the characterization of hydrocarbons has not been practical due to several limitations. One early limitation to Raman analysis was the absence of a high intensity and stable excitation source. This problem has been overcome with the advent of lasers. Another limitation was the presence of fluorescence in hydrocarbon fuels when excited by visible lasers. However, the development of Fourier-transform Raman spectrometers now allows Raman spectra to be collected using near-IR lasers (e.g …


Copper Complexation And Speciation In The Western South And Equatorial Atlantic Ocean, John A. Consolvo Oct 2000

Copper Complexation And Speciation In The Western South And Equatorial Atlantic Ocean, John A. Consolvo

Chemistry & Biochemistry Theses & Dissertations

Presented here are the first data on copper complexation and speciation in the South Atlantic Ocean. Samples were collected at six vertical profile stations and along the surface (1m) transect during the 1996 IOC Baseline Contaminant Survey. Copper complexation measurements were made for the surface transect (1m) samples and three of the six vertical profile stations (1m - ~500m) using differential pulse anodic stripping voltammetry (DPASV) with a thin mercury film, rotating glassy carbon disk electrode (TMFRGCDE).

A strong organic copper complexing ligand (L1; log K' cuL1/cu2+ > 11. 8 ± 0 .4) was detected in 57% of all …


Studies Related To The Design And Implementation Of A Magnetic Suspension And Balance System, Syed Adeel Akhtar Jafri Oct 2000

Studies Related To The Design And Implementation Of A Magnetic Suspension And Balance System, Syed Adeel Akhtar Jafri

Electrical & Computer Engineering Theses & Dissertations

This thesis presents studies related to the magnetic suspension and balance system (MSBS) of the Princeton/ONR High Reynolds Number Testing Facility (HRTF). The main motivation for developing the MSBS is to provide interference free aero/hydrodynamic testing of submersible models, which will lead to more accurate measurements. From the controls point of view, the main specification of the MSBS is to robustly control the position of a submersible model in five degrees of freedom (DOF), including three translational as well as pitching and yawing positions. The MSBS should not only regulate the submersible model's position but should also allow for small …


The Cracker Patch Choice: An Analysis Of Post Hoc Security Techniques, Crispin Cowan, Heather Hinton, Calton Pu, Jonathan Walpole Oct 2000

The Cracker Patch Choice: An Analysis Of Post Hoc Security Techniques, Crispin Cowan, Heather Hinton, Calton Pu, Jonathan Walpole

Computer Science Faculty Publications and Presentations

It has long been known that security is easiest to achieve when it is designed in from the start. Unfortunately, it has also become evident that systems built with security as a priority are rarely selected for wide spread deployment, because most consumers choose features, convenience, and performance over security. Thus security officers are often denied the option of choosing a truly secure solution, and instead must choose among a variety of post hoc security adaptations. We classify security enhancing methods, and compare and contrast these methods in terms of their effectiveness vs. cost of deployment. Our analysis provides practitioners …


Side Collision Warning System For Transit Buses, Sue Mcneil, David Duggins, Christoph Mertz, Arne Suppe, Chuck Thorpe Oct 2000

Side Collision Warning System For Transit Buses, Sue Mcneil, David Duggins, Christoph Mertz, Arne Suppe, Chuck Thorpe

Research Collection School Of Computing and Information Systems

Transit buses are involved in many more accidents than other vehicles. Collision warning systems (CWS) are therefore placed most efficiently on these buses. In our project, we investigate their operating environment and available technologies to develop performance specifications for such CWS. The paper discusses our findings of transit buses driving through very cluttered surroundings and being involved in many different types of accidents where currently available CWS no not work effectively. One of the focuses of our work is pedestrians around the bus and their detection.


Mathews County Shoreline Situation Report (2000), Marcia Berman, Harry Berquist, Sharon Dewing, J. B. Glover, Carl Hershner, Tamia Rudnicky, Dan Schatt, Kevin Skunda Oct 2000

Mathews County Shoreline Situation Report (2000), Marcia Berman, Harry Berquist, Sharon Dewing, J. B. Glover, Carl Hershner, Tamia Rudnicky, Dan Schatt, Kevin Skunda

Reports

No abstract provided.


End-To-End Authorization, Jon Howell, David Kotz Oct 2000

End-To-End Authorization, Jon Howell, David Kotz

Dartmouth Scholarship

Many boundaries impede the flow of authorization information, forcing applications that span those boundaries into hop-by-hop approaches to authorization. We present a unified approach to authorization. Our approach allows applications that span administrative, network, abstraction, and protocol boundaries to understand the end-to-end authority that justifies any given request. The resulting distributed systems are more secure and easier to audit. \par We describe boundaries that can interfere with end-to-end authorization, and outline our unified approach. We describe the system we built and the applications we adapted to use our unified authorization system, and measure its costs. We conclude that our system …


Fabrication And Characterization Of Silicon Field Emitter Arrays, Aaron M. Brock Oct 2000

Fabrication And Characterization Of Silicon Field Emitter Arrays, Aaron M. Brock

Electrical & Computer Engineering Theses & Dissertations

Field emission is a process through which the application of a large electric field to the surface of a material causes electron emission into vacuum. The electron emission current is a strong function of the geometry of the emitting material. The focus of this thesis is to investigate the effect of geometry on the emission current. Specifically, silicon field emitter arrays were fabricated using two separate fabrication processes termed the standard process and the new process. The uniformity of the arrays was measured experimentally. The arrays were used in field emission tests from which parameters controlling field emission were extracted. …


Phytosociological Analysis Of Restored And Managed Grassland Habitat Within An Urban National Park, Andrew M. Greller, Celestine Durando, Leslie F. Marcus, D. Siril A. Wijesundara, Michael D. Byer, Robert Cook, John T. Tanacredi Ph.D. Oct 2000

Phytosociological Analysis Of Restored And Managed Grassland Habitat Within An Urban National Park, Andrew M. Greller, Celestine Durando, Leslie F. Marcus, D. Siril A. Wijesundara, Michael D. Byer, Robert Cook, John T. Tanacredi Ph.D.

Faculty Works: CERCOM (1977-2016)

Floyd Bennett Field (FBF), 579 ha in extent, is a division of Gateway National Recreation Area. It is the site of a former airfield, constructed by filling salt marshes with dredged materials. Except for the portion known locally as the “North Forty,” all sections of FBF have been cut over to maintain low vegetation. A grassland management plan (GRAMP) for 165 ha was initiated in 1986, to maintain habitats for open-country birds. Over the next few years, encroaching woody vegetation was removed manually and mechanically from the management area. Since then, it has been maintained as a grassland and receives …


Relationship Of Molecular Structure To The Mechanism Of Lysophospholipid-Induced Smooth Muscle Cell Proliferation, Yuh-Cherng Chai, David Binion, Guy Chisholm Sep 2000

Relationship Of Molecular Structure To The Mechanism Of Lysophospholipid-Induced Smooth Muscle Cell Proliferation, Yuh-Cherng Chai, David Binion, Guy Chisholm

Yuh-Cherng Chai

No abstract provided.


Clustering Irregular Shapes Using High-Order Neurons, H. Lipson, Hava Siegelmann Sep 2000

Clustering Irregular Shapes Using High-Order Neurons, H. Lipson, Hava Siegelmann

Hava Siegelmann

This article introduces a method for clustering irregularly shaped data arrangements using high-order neurons. Complex analytical shapes are modeled by replacing the classic synaptic weight of the neuron by high-order tensors in homogeneous coordinates. In the first- and second-order cases, this neuron corresponds to a classic neuron and to an ellipsoidalmetric neuron. We show how high-order shapes can be formulated to follow the maximum-correlation activation principle and permit simple local Hebbian learning. We also demonstrate decomposition of spatial arrangements of data clusters, including very close and partially overlapping clusters, which are difficult to distinguish using classic neurons. Superior results are …


Exospheric Models For The X-Ray Emission From Single Wolf-Rayet Stars., R. Ignace, L. M. Oskinova Sep 2000

Exospheric Models For The X-Ray Emission From Single Wolf-Rayet Stars., R. Ignace, L. M. Oskinova

Richard Ignace

We review existing ROSAT detections of single Galactic Wolf-Rayet (WR) stars and develop wind models to interpret the X-ray emission. The ROSAT data, consisting of bandpass detections from the ROSAT All-Sky Survey (RASS) and some pointed observations, exhibit no correlations of the WR X-ray luminosity (LX) with any star or wind parameters of interest (e.g. bolometric luminosity, mass-loss rate or wind kinetic energy), although the dispersion in the measurements is quite large. The lack of correlation between X-ray luminosity and wind parameters among the WR stars is unlike that of their progenitors, the O stars, which show …


Bezpośrednie I Pośrednie Efekty Wprowadzenia Ciągłego Odlewania Stali W Bilansie Emisji Zanieczyszczeń Z Huty Żelaza, Marian Mazur, Marek Bogacki, Robert Oleniacz Sep 2000

Bezpośrednie I Pośrednie Efekty Wprowadzenia Ciągłego Odlewania Stali W Bilansie Emisji Zanieczyszczeń Z Huty Żelaza, Marian Mazur, Marek Bogacki, Robert Oleniacz

Robert Oleniacz

This paper presents a comprehensive analysis of the impact of continuous casting technology on emissions of air pollutants from "Katowice" Steelworks in Dąbrowa Górnicza (Poland). Sources of emissions occurring in the manufacturing process and emissions levels have been identified. Implementation of continuous casting of steel has increased the efficiency of production and brought substantial ecological effects.

English title: Direct and indirect effects of introduction of continuous casting of steel in the balance sheet of pollutant emissions from "Katowice" Steelworks.