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2004

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Articles 2731 - 2760 of 4447

Full-Text Articles in Physical Sciences and Mathematics

Citizen Suits And Sustainability, John C. Dernbach Jan 2004

Citizen Suits And Sustainability, John C. Dernbach

John C. Dernbach

No abstract provided.

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An Introduction To Artificial Intelligence And Legal Reasoning: Using Xtalk To Model The Alien Tort Claims Act And Torture Victim Protection Act, Eric A. Engle Jan 2004

An Introduction To Artificial Intelligence And Legal Reasoning: Using Xtalk To Model The Alien Tort Claims Act And Torture Victim Protection Act, Eric A. Engle

Eric A. Engle

This paper presents an introduction to artificial intelligence for legal scholars and includes a computer program that determines the existence of jurisdiction, defences, and applicability of the Alien Tort Claims Act and Torture Victims Protection Act. The paper includes a discussion of the limits and implications of computer programming in formal representations of the law. Concluding that formalization of the law reveals implicit weaknesses in reductionist legal theories, this paper emphasizes the limitations in practice of such theories.

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Bioconductor: Open Software Development For Computational Biology And Bioinformatics, Robert C. Gentleman, Vincent J. Carey, Douglas J. Bates, Benjamin M. Bolstad, Marcel Dettling, Sandrine Dudoit, Byron Ellis, Laurent Gautier, Yongchao Ge, Jeff Gentry, Kurt Hornik, Torsten Hothorn, Wolfgang Huber, Stefano Iacus, Rafael Irizarry, Friedrich Leisch, Cheng Li, Martin Maechler, Anthony J. Rossini, Guenther Sawitzki, Colin Smith, Gordon K. Smyth, Luke Tierney, Yee Hwa Yang, Jianhua Zhang Jan 2004

Bioconductor: Open Software Development For Computational Biology And Bioinformatics, Robert C. Gentleman, Vincent J. Carey, Douglas J. Bates, Benjamin M. Bolstad, Marcel Dettling, Sandrine Dudoit, Byron Ellis, Laurent Gautier, Yongchao Ge, Jeff Gentry, Kurt Hornik, Torsten Hothorn, Wolfgang Huber, Stefano Iacus, Rafael Irizarry, Friedrich Leisch, Cheng Li, Martin Maechler, Anthony J. Rossini, Guenther Sawitzki, Colin Smith, Gordon K. Smyth, Luke Tierney, Yee Hwa Yang, Jianhua Zhang

Bioconductor Project Working Papers

The Bioconductor project is an initiative for the collaborative creation of extensible software for computational biology and bioinformatics. We detail some of the design decisions, software paradigms and operational strategies that have allowed a small number of researchers to provide a wide variety of innovative, extensible, software solutions in a relatively short time. The use of an object oriented programming paradigm, the adoption and development of a software package system, designing by contract, distributed development and collaboration with other projects are elements of this project's success. Individually, each of these concepts are useful and important but when combined they have …

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Multiple Testing. Part Iii. Procedures For Control Of The Generalized Family-Wise Error Rate And Proportion Of False Positives, Mark J. Van Der Laan, Sandrine Dudoit, Katherine S. Pollard Jan 2004

Multiple Testing. Part Iii. Procedures For Control Of The Generalized Family-Wise Error Rate And Proportion Of False Positives, Mark J. Van Der Laan, Sandrine Dudoit, Katherine S. Pollard

U.C. Berkeley Division of Biostatistics Working Paper Series

The accompanying articles by Dudoit et al. (2003b) and van der Laan et al. (2003) provide single-step and step-down resampling-based multiple testing procedures that asymptotically control the family-wise error rate (FWER) for general null hypotheses and test statistics. The proposed procedures fundamentally differ from existing approaches in the choice of null distribution for deriving cut-offs for the test statistics and are shown to provide asymptotic control of the FWER under general data generating distributions, without the need for conditions such as subset pivotality. In this article, we show that any multiple testing procedure (asymptotically) controlling the FWER at level alpha …

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Heavy Quark Production By A Quasi-Classical Color Field In Proton-Nucleus Collisions, Kirill Tuchin Jan 2004

Heavy Quark Production By A Quasi-Classical Color Field In Proton-Nucleus Collisions, Kirill Tuchin

Kirill Tuchin

We calculate the inclusive heavy quark production cross section for proton-nucleus collisions at high energies. We perform calculation in a quasi-classical approximation (McLerran-Venugopalan model) neglecting all low-x evolution effects. The derived expression for the differential cross section can be applied for studying the heavy quark production in the central rapidity region at RHIC.

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Coherent Vibrational Oscillation In Gold Prismatic Monolayer Periodic Nanoparticle Arrays, Wenyu Huang, Wei Qian, Mostafa A. El-Sayed Jan 2004

Coherent Vibrational Oscillation In Gold Prismatic Monolayer Periodic Nanoparticle Arrays, Wenyu Huang, Wei Qian, Mostafa A. El-Sayed

Wenyu Huang

We studied the ultrafast laser-induced coherent phonon oscillation in prismatic shaped gold nanoparticles assembled in monolayer periodic arrays by using the nanosphere lithographic technique. The amplitude and phase of the oscillation observed by ultrafast pump−probe transient spectroscopy is monitored as the wavelength of the dipolar surface plasmon absorption decreases. At a certain wavelength, the oscillation could not be observed. As the monitoring wavelength decreases further, the sign of the amplitude changes. From the wavelength at which the oscillation is not detected, the dependence of the absorption maxima on the size of the nanoparticles, the changes in the nanoparticle size are …

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Nuclear Modification Factor In D + Au Collisions: Onset Of Suppression In The Color Glass Condensate, Dmitri Kharzeev, Yuri V. Kovchegov, Kirill Tuchin Jan 2004

Nuclear Modification Factor In D + Au Collisions: Onset Of Suppression In The Color Glass Condensate, Dmitri Kharzeev, Yuri V. Kovchegov, Kirill Tuchin

Kirill Tuchin

We perform a quantitative analysis of the nuclear modification factor in deuteron-gold collisions R dAu within the Color Glass Condensate approach, and compare our results with the recent data from RHIC experiments. Our model leads to Cronin enhancement at mid-rapidity, while at forward rapidities it predicts strong suppression of R dAu at all PT due to low-x evolution. We demonstrate that our results are consistent with the data for dAu charged hadron spectra, R dAu and R CP recently reported for rapidities in the interval η=0-3.2 by the BRAHMS experiment at RHIC. We also make a prediction for R pA …

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Photochemical Generation Of Nitrenium Ions From Protonated 1,1-Diarylhydrazines, Arthur Winter, Selina I. Thomas, Andrew C. Kung, Daniel E. Falvey Jan 2004

Photochemical Generation Of Nitrenium Ions From Protonated 1,1-Diarylhydrazines, Arthur Winter, Selina I. Thomas, Andrew C. Kung, Daniel E. Falvey

Arthur Winter

Laser flash photolysis experiments, chemical trapping studies, and time-dependent density functional theory calculations demonstrate that photolysis of protonated 1,1-diarylhydrazines generates N,N-diarylnitrenium ions.

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Effect Of Meta Electron-Donating Groups On The Electronic Structure Of Substituted Phenyl Nitrenium Ions, Arthur Winter Jan 2004

Effect Of Meta Electron-Donating Groups On The Electronic Structure Of Substituted Phenyl Nitrenium Ions, Arthur Winter

Arthur Winter

Density functional theory (UB3LYP/6-31G(d,p)) was used to determine substituent effects on the singlet−triplet-state energy gap for 21 meta-substituted phenylnitrenium ions. It was found that strongly electron-donating substituents stabilize the triplet state relative to the singlet state. With sufficiently strong meta electron donors (e.g., m,m‘-diaminophenylnitrenium ion) the triplet is predicted to be the ground state. Analysis of equilibrium geometries, Kohn−Sham orbital distributions, and Mulliken spin densities for the triplet states of this series of nitrenium ions leads to the conclusion that there are two spatially distinct types of low-energy triplet states. Simple arylnitrenium ions such as phenylnitrenium ions as well as …

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Particle Correlations At High Partonic Density, Kirill Tuchin Jan 2004

Particle Correlations At High Partonic Density, Kirill Tuchin

Kirill Tuchin

We discuss manifestations of the particle correlations at high partonic density in the heavy-ion collisions at RHIC. In particular, we argue that the elliptic flow variable v% is dominated by particle correlations at high PT

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Qcd In Curved Space-Time: A Conformal Bag Model, Dmitri Kharzeev, Eugene Levin, Kirill Tuchin Jan 2004

Qcd In Curved Space-Time: A Conformal Bag Model, Dmitri Kharzeev, Eugene Levin, Kirill Tuchin

Kirill Tuchin

We construct an effective low energy Lagrangian using constraints imposed by the renormalization group. Degrees of freedom are gluons and a scalar glueball. This effective theory has a dual description as classical gluodynamics on a curved conformal background. Color fields are dynamically confined, and the strong coupling freezes at distances larger than the glueball size. We make specific predictions (in particular, on the Nc dependence of glueball properties) which can be tested in lattice simulations of gluodynamics.

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2,2':6',2"-Terpyridine N,N',N"-Trioxide, Kraig A. Wheeler, Scott E. Mckay, Silas C. Blackstock Jan 2004

2,2':6',2"-Terpyridine N,N',N"-Trioxide, Kraig A. Wheeler, Scott E. Mckay, Silas C. Blackstock

Kraig A. Wheeler

No abstract provided.

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Nanoscale Electronics Based On 2d Dopant Patterns In Silicon, T. -C. Shen, J. S. Kline, T. Schenkel, S. J. Robinson, J. -Y. Ji, C. L. Yang, R. R. Du, J. R. Tucker Jan 2004

Nanoscale Electronics Based On 2d Dopant Patterns In Silicon, T. -C. Shen, J. S. Kline, T. Schenkel, S. J. Robinson, J. -Y. Ji, C. L. Yang, R. R. Du, J. R. Tucker

T. -C. Shen

A nanoscale fabrication process compatible with present Si technology is reported. Preimplanted contact arrays provide external leads for scanning tunneling microscope (STM)-defined dopantpatterns. The STM’s low energy electron beam removes hydrogen from H terminated Si(100) surfaces for selective adsorption of PH3 precursor molecules, followed by room temperature Si overgrowth and 500 °C rapid thermal anneal to create activated P-donor patterns in contact with As+-implanted lines. Electrical and magnetoresistance measurements are reported here on 50 and 95 nm-wide P-donor lines, along with Ga-acceptor wires created by focused ion beams, as a means for extending Si device fabrication toward …

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Effects Of Counterion Fluctuations In A Polyelectrolyte Brush, Christian Santangelo, A.W.C. Lau Jan 2004

Effects Of Counterion Fluctuations In A Polyelectrolyte Brush, Christian Santangelo, A.W.C. Lau

Christian Santangelo

We investigate the effect of counterion fluctuations in a single polyelectrolyte brush in the absence of added salt by systematically expanding the counterion free energy about Poisson-Boltzmann mean-field theory. We find that for strongly charged brushes, there is a collapse regime in which the brush height decreases with increasing charge on the polyelectrolyte chains. The transition to this collapsed regime is similar to the liquid-gas transition, which has a first-order line terminating at a critical point. We find that, for monovalent counterions, the transition is discontinuous in theta solvent, while for multivalent counterions, the transition is generally continuous. For collapsed …

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The Relationship Between Exsolution And Magnetic Properties In Hemo-Ilmenite: Insights From Mössbauer Spectroscopy With Implications For Planetary Magnetic Anomalies, Laurie Brown, M. D. Dyar, S. A. Mcenroe, E. Murad, H. Schiellerup Jan 2004

The Relationship Between Exsolution And Magnetic Properties In Hemo-Ilmenite: Insights From Mössbauer Spectroscopy With Implications For Planetary Magnetic Anomalies, Laurie Brown, M. D. Dyar, S. A. Mcenroe, E. Murad, H. Schiellerup

Laurie Brown

Remanence properties of ilmenites with exsolved hematite have recently been the object of much study, because their high natural remanent magnetization (NRM) is greater than predicted for these two minerals. X-ray diffraction (XRD) and Mössbauer spectroscopy in conjunction with electron microprobe and NRM measurements were used to explore the possibility that single domain (SD) hematite lamellae in the ilmenite host could explain the observed remanence, and to determine if magnetite is present. XRD results show the presence of ilmenite and hematite. Mössbauer data show that only species assigned to hematite, ilmenite, and a small amount of tetrahedral Fe3+ are present. …

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Paleomagnetic Directions And 40ar/39ar Ages From The Tatara-San Pedro Volcanic Complex, Chilean Andes: Lava Record Of A Matuyama-Brunhes Precursor?, Laurie Brown, J. C. Pickens, B. S. Singer, B. R. Jicha Jan 2004

Paleomagnetic Directions And 40ar/39ar Ages From The Tatara-San Pedro Volcanic Complex, Chilean Andes: Lava Record Of A Matuyama-Brunhes Precursor?, Laurie Brown, J. C. Pickens, B. S. Singer, B. R. Jicha

Laurie Brown

Lava flows within Quebrada Turbia valley of the Tatara San Pedro volcanic complex, in central Chile (36°S, 289°E), preserve a detailed record of what was presumed to be the Matuyama-Brunhes geomagnetic reversal. A sampling traverse in the central west wall of the valley yields reverse and transitional polarity flows of the Quebrada Turbia sequence. Two kilometers to the north, another section yields 17 transitional flows from the same volcanic sequence overlain by flows with normal polarity. The 40Ar/39Ar incremental heating experiments on lavas within the two sections provide nine independent age determinations and yield a weighted mean of 791.7 ± …

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8th Bratislava International Conference On Modified Polymers: Modpol2003, Otto Vogl, Maria Omastova Jan 2004

8th Bratislava International Conference On Modified Polymers: Modpol2003, Otto Vogl, Maria Omastova

Otto Vogl

No abstract provided.

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A. Cover Page, Title Page, Table Of Contents, And Forward, Otto Vogl Jan 2004

A. Cover Page, Title Page, Table Of Contents, And Forward, Otto Vogl

Otto Vogl

The History of the Pacific Polymer Federation (PPF) describes the background and pursuit that was needed to create the PPF and bring it to a functioning organization. It includes a general description, as well as edited Pacific Polymer Newsletters and articles that have been written in Polymer News describing additional PPF activities and the Pacific Polymer Conferences.

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D. Founding Of The Pacific Polymer Federation, Otto Vogl Jan 2004

D. Founding Of The Pacific Polymer Federation, Otto Vogl

Otto Vogl

An account of the process which led to the founding of the Pacific Polymer Federation and a copy of the Constitution of the Pacific Polymer Federation.

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E. President Of The Pacific Polymer Federation, Otto Vogl Jan 2004

E. President Of The Pacific Polymer Federation, Otto Vogl

Otto Vogl

A history of the first president of the Pacific Polymer Federation.

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H. Pacific Polymer Federation Conference Reports, Otto Vogl Jan 2004

H. Pacific Polymer Federation Conference Reports, Otto Vogl

Otto Vogl

Reports of the first through the sixth Pacific Polymer Federation Conferences, held biennially 1989-1999. Also includes reporting on the Pacific Polymer Federation.

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G. Excerpts Of Pacific Polymer Federation Newsletters, Otto Vogl Jan 2004

G. Excerpts Of Pacific Polymer Federation Newsletters, Otto Vogl

Otto Vogl

Excerpts of Pacific Polymer Federation Newsletters 1-13, 1989-2003. Covers the presidencies of Otto Vogl, Takeo Saegusa, Joseph Salamone, Chung Yup Kim, Fosong Wang, Takeshi Ogawa, and Supawan Tantayanon.

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Projected Temperature Changes Along The American Cordillera And The Planned Gcos Network, Raymond S. Bradley, F. T. Keimig, H. F. Diaz Jan 2004

Projected Temperature Changes Along The American Cordillera And The Planned Gcos Network, Raymond S. Bradley, F. T. Keimig, H. F. Diaz

Raymond S Bradley

Analysis of 7 GCM simulations with 2x CO2 levels shows large and statistically significant free air temperature changes (compared to controls) along the axis of the American Cordillera (from Alaska to southern Chile). At all latitudes, the modeled change in temperature increases with elevation. Temperature increases are especially large in boreal summer months from ∼35–50°N, and year-round in the high mountains of Peru, Bolivia and northern Chile. If these models are correct, mountain ranges that extend high into the lower troposphere are likely to experience significant warming, with implications for glacier mass balance and water resources, montane ecosystems and high …

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Magnetic Anomalies, Layered Intrusions And Mars, Laurie Brown, S. A. Mcenroe, J. R. Skilbrei, P. Robinson, F. Heidelbach, F. Langenhorst Jan 2004

Magnetic Anomalies, Layered Intrusions And Mars, Laurie Brown, S. A. Mcenroe, J. R. Skilbrei, P. Robinson, F. Heidelbach, F. Langenhorst

Laurie Brown

Studies of remanence-controlled magnetic anomalies on Earth provide possibilities to interpret the nature of crustal rocks that cause the large remanent anomalies on Mars. What types of conditions on Earth can create large remanent magnetic anomalies? Such an anomaly, extending for 20 km centered over a norite layer in the Bjerkreim-Sokndal (BKS) Intrusion, shows a minimum −13000 nT below background in the helicopter survey. Modeling of the anomaly requires a natural remanent magnetization (NRM) value of 24 A/m, similar to values measured in norite samples and to values invoked to explain the anomalies on Mars. Preliminary magnetic assessment considers the …

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Distribution Of Counterions Near Discretely Charged Planes And Rods, M. L. Henle, Christian Santangelo, D. M. Patel, P. A. Pincus Jan 2004

Distribution Of Counterions Near Discretely Charged Planes And Rods, M. L. Henle, Christian Santangelo, D. M. Patel, P. A. Pincus

Christian Santangelo

Realistic charged macromolecules are characterized by discrete (rather than homogeneous) charge distributions. We investigate the effects of surface charge discretization on the counterion distribution at the level of mean-field theory using a two-state model. Both planar and cylindrical geometries are considered; for the latter case, we compare our results to numerical solutions of the full Poisson-Boltzmann equation. We find that the discretization of the surface charge can cause enhanced localization of the counterions near the surface; for charged cylinders, counterion condensation can exceed Oosawa-Manning condensation.

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Structural And Computational Depth Of Diffusion Limited Aggregation, D. Tillberg, Jonathan Machta Jan 2004

Structural And Computational Depth Of Diffusion Limited Aggregation, D. Tillberg, Jonathan Machta

Jonathan Machta

Diffusion-limited aggregation (DLA) is studied from the perspective of computational complexity. A parallel algorithm is exhibited that requires a number of steps that scales as the depth of the tree defined by the cluster. The existence of this algorithm suggests a connection between a fundamental computational and structural property of DLA.

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Long Distance Chiral Corrections In B Meson Amplitudes, Juan J. Sanz-Cillero, John Donoghue, Andreas Ross Jan 2004

Long Distance Chiral Corrections In B Meson Amplitudes, Juan J. Sanz-Cillero, John Donoghue, Andreas Ross

John Donoghue

We discuss the chiral corrections to f_B and B_B with particular emphasis on determining the portion of the correction that arises from long distance physics. For very small pion and kaon masses all of the usual corrections are truly long distance, while for larger masses the long distance portion decreases. These chiral corrections have been used to extrapolate lattice calculations towards the physical region of lighter masses. We show in particular that the chiral extrapolation is better behaved if only the long distance portion of the correction is used.

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Precision Zeeman-Stark Spectroscopy Of The Metastable A(1)[Σ+3] State Of Pbo, David Kawall, F. Bay, S. Bickman, Y. Jiang, D. Demille Jan 2004

Precision Zeeman-Stark Spectroscopy Of The Metastable A(1)[Σ+3] State Of Pbo, David Kawall, F. Bay, S. Bickman, Y. Jiang, D. Demille

David Kawall

The metastable a(1)[Σ+3] state of PbO has been suggested as a suitable system in which to search for the electric dipole moment of the electron. We report here the development of experimental techniques allowing high-sensitivity measurements of Zeeman and Stark effects in this system, similar to those required for such a search. We observe Zeeman quantum beats in fluorescence from a vapor cell of PbO, with shot-noise limited extraction of the quantum beat frequencies, high counting rates, and long coherence times. We argue that improvement in sensitivity to the electron electric dipole moment by at least 2 orders of magnitude …

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A 1500-Year El Niño/Southern Oscillation And Rainfall History For The Isthmus Of Panama From Speleothem Calcite, Stephen J. Burns, M. S. Lachniet, D. R. Piperno, Y. Asmerom, V. J. Polyak, C. M. Moy, K. Christenson Jan 2004

A 1500-Year El Niño/Southern Oscillation And Rainfall History For The Isthmus Of Panama From Speleothem Calcite, Stephen J. Burns, M. S. Lachniet, D. R. Piperno, Y. Asmerom, V. J. Polyak, C. M. Moy, K. Christenson

Stephen J Burns

The effect of the El Niño/Southern Oscillation (ENSO) on tropical rainfall variations of the past 2 millennia is largely unknown. High-resolution monsoon records are sparse, despite the role of ENSO in generating global hydrologic anomalies in modern climate. To investigate the relationship between ENSO and the Central American Monsoon, we generated a high-resolution (∼2.9 years/sample) oxygen-isotope monsoon rainfall record from a U/Th-dated stalagmite (180 B.C. to 1310 A.D.) from the Isthmus of Panama. We present evidence for a weakened monsoon during the “High Medieval” (1100–1200 A.D.) and the Classic Maya Collapse (750–950 A.D.). Rainfall decreased and was more variable after …

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F. Growth Of The Pacific Polymer Federation, Otto Vogl Jan 2004

F. Growth Of The Pacific Polymer Federation, Otto Vogl

Otto Vogl

Describes the growth and development of the Pacific Polymer Federation,

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