bluuebunny/crossref_metadata_2025 huggingface dataset:
Solar wind from the coronal hole boundaries
Authors: Schwadron N. A. , McComas D. J. , Elliott H. A. , Gloeckler G. , Geiss J. , von Steiger R.
Published: April 2005

Recent studies using in situ observations established that the interface between fast and slow wind in interplanetary space has two distinct parts: a smoothly varying boundary layer flow that flanks fast wind from coronal holes and a sharper plasma discontinuity between intermediate and slow solar wind. Other studies using in situ observations and modeling have demonstrated the existence of the sub‐Parker spiral structure of the heliospheric magnetic field in which the magnetic connection between fast and slow wind created by foot point motion at the Sun deforms field lines, making them significantly less transverse than the Parker spiral. Here we model the formation of corotating interaction regions, and by including a coronal hole boundary layer (CHBL) and magnetic foot point motion across the coronal hole boundary back at the Sun we explain the detailed, characteristic variations in composition and magnetic field orientation observed in interplanetary space. Our model accomplishes this using only two free parameters, with all other quantities derived directly from solar wind observations. Through the model we trace the observed interplanetary variations back to an intrinsic two‐part structure in the source of solar wind at the Sun. These parts are (1) a CHBL that encircles the coronal hole and has a smooth transition in the source properties that produce the fast through intermediate speed (∼600 km s−1) solar wind and (2) a sharp coronal hole discontinuity separating the distinct sources of solar wind with intermediate speeds and temperatures from slow solar wind. This study establishes the connection between the characteristic variations of the solar wind speed, charge state composition, and magnetic field orientation observed in situ near 5 AU with their sources in the two‐part structure of coronal hole boundaries back at the Sun.
Permeability creation and damage due to massive fluid injections into granite at 3.5 km at Soultz: 2. Critical stress and fracture strength
Authors: Evans Keith F.
Published: April 2005

The stress acting on fractures in a 3.5 km deep borehole in granite is examined to place constraints on fracture strength and to evaluate whether permeable fractures tended to be “critically stressed.” Two data sets consisting of some 500 fractures are analyzed. The first considers the permeable/impermeable fracture populations in their natural state. The second considers the populations after the hole had been subject to a prolonged, 9 MPa overpressure in two major injections which increased the number of permeable fractures from 18 to more than 95. For both data sets it is found that permeable fractures are critically stressed inasmuch as they support levels of shear stress that would be verging on failure if their strength were governed by a Coulomb friction law with a coefficient of 0.6–1.0. However, the vast majority of impermeable fractures are also critically stressed, implying that critical stressing is a necessary, but not a sufficient, condition for permeability to develop. Most permeable fractures showed evidence of shear failure after the injections and tended to occur in hydrothermally altered cataclastic shear zones, suggesting that they may have been relatively weak because of the presence of illite. To prevent failure of the impermeable fractures during the injections requires a cohesion of at least 6.5 MPa to augment a maximum allowable friction coefficient of 1.0. These are probably early mode 1 fractures that are sealed primarily with calcite. The strength of the shear zones appears to be significantly greater than the illite‐rich fractures from which they are composed. This imposes constraints on their internal architecture.
Magnitude‐dependent Omori law: Theory and empirical study
Authors: Ouillon G. , Sornette D.
Published: April 2005

We propose a new physically based “multifractal stress activation” model of earthquake interaction and triggering based on two simple ingredients: (1) a seismic rupture results from activated processes giving an exponential dependence on the local stress and (2) the stress relaxation has a long memory. The combination of these two effects predicts in a rather general way that seismic decay rates after main shocks follow the Omori law ∼1/tpwith exponentsplinearly increasing with the magnitudeMLof the main shock. We carefully test the prediction on the magnitude dependence ofpby a detailed analysis of earthquake sequences in the southern California earthquake catalog. We find power law relaxations of seismic sequences triggered by main shocks with exponentspincreasing with the main shock magnitude by approximately 0.1–0.15 for each magnitude unit increase, fromp(ML= 3) ≈ 0.6 top(ML= 7) ≈ 1.1, in good agreement with the prediction of the multifractal model. The results are robust with respect to different time intervals, magnitude ranges, and declustering methods. When applied to synthetic catalogs generated by the epidemic‐type aftershock sequence (ETAS) model constituting a strong null hypothesis with built‐in magnitude‐independentpvalues, our procedure recovers the correct magnitude‐independentpvalues. Our analysis thus suggests that a new important fact of seismicity has been unearthed. We discuss alternative interpretations of the data and describe other predictions of the model.
Spectroscopic Studies of Diatomic Gallium Halides
Authors: Singh V. B.
Published: April 2005

An extensive study of the available spectroscopic information on four gallium monohalides has been conducted. The literature survey extends to early 2003 and the experimental and theoretical data on the molecular constants for the ground state, as well as for the excited states of these molecules, is presented. A brief discussion on the spectroscopic properties of different electronic states, ionization potentials, ground state dissociation energies, and percentage ionic character are given. The Rydberg–Klein–Rees potentials for the electronic states and centrifugal distortion constants for the observed vibrational levels for the electronic states of GaX (X=F, Cl, Br, and I) are also presented.
Theory of heteronuclear decoupling in solid-state nuclear magnetic resonance using multipole-multimode Floquet theory
Authors: Ramachandran Ramesh , Bajaj Vikram S. , Griffin Robert G.
Published: April 2005

A formal theory for heteronuclear decoupling in solid-state magic angle spinning (MAS) nuclear magnetic resonance experiments is presented as a first application of multipole-multimode Floquet theory. The method permits a straightforward construction of the multispin basis and describes the spin dynamics via effective Floquet Hamiltonians obtained using the van Vleck transformation method in the Floquet–Liouville space. As a test case, we consider a model three-spin system (I2S) under asynchronous time modulations (both MAS and rf irradiation) and derive effective Hamiltonians for describing the spin dynamics in the Floquet–Liouville space during heteronuclear decoupling. Furthermore, we describe and evaluate the origin of cross terms between the various anisotropic interactions and illustrate their exact contributions to the spin dynamics. The theory presented herein should be applicable to the design and understanding of pulse sequences for heteronuclear and homonuclear recoupling and decoupling.
Measurements and modeling of plasma flow damping in the Helically Symmetric eXperiment
Authors: Gerhardt S. P. , Talmadge J. N. , Canik J. M. , Anderson D. T.
Published: April 2005

Measurements of plasma flow damping have been made in the Helically Symmetric eXperiment [F. S. B. Anderson, A. F. Almagri, D. T. Anderson, P. G. Mathews, J. N. Talmadge, and J. L. Shohet, Fusion Technology 27, 273 (1995)] using a biased electrode to impulsively spin the plasma and Mach probes to measure the rotation. There is a distinct asymmetry between the spin-up when the bias is initiated and relaxation when the electrode current is broken. In each case, two time-scales are observed in the evolution of the plasma flow. These observations motivate the development of new neoclassical modeling techniques, including a new model where the fast increment of the electric field initiates the spin-up process. The flow in the quasisymmetric configuration rises more slowly and to a higher value than in a configuration with the quasisymmetry broken, and the rise time-scale is in reasonable agreement with the neoclassical spin-up model. The flows decay more slowly in the quasisymmetry configuration than in the configuration with the quasisymmetry broken, although the decay rates are significantly faster than the neoclassical prediction.
The role of relativity in the optical response of gold within the time-dependent current-density-functional theory
Authors: Romaniello P. , de Boeij P. L.
Published: April 2005

We included relativistic effects in the formulation of the time-dependent current-density-functional theory for the calculation of linear response properties of metals [P. Romaniello and P. L. de Boeij, Phys. Rev. B (to be published)]. We treat the dominant scalar-relativistic effects using the zeroth-order regular approximation in the ground-state density-functional theory calculations, as well as in the time-dependent response calculations. The results for the dielectric function of gold calculated in the spectral range of 0–10eV are compared with experimental data reported in literature and recent ellipsometric measurements. As well known, relativistic effects strongly influence the color of gold. We find that the onset of interband transitions is shifted from around 3.5eV, obtained in a nonrelativistic calculation, to around 1.9eV when relativity is included. With the inclusion of the scalar-relativistic effects there is an overall improvement of both real and imaginary parts of the dielectric function over the nonrelativistic ones. Nevertheless some important features in the absorption spectrum are not well reproduced, but can be explained in terms of spin-orbit coupling effects. The remaining deviations are attributed to the underestimation of the interband gap (5d-6sp band gap) in the local-density approximation and to the use of the adiabatic local-density approximation in the response calculation.
Microstructure of (Ga,Mn)As∕GaAs digital ferromagnetic heterostructures
Authors: Kong X. , Trampert A. , Guo X. X. , Kolovos-Vellianitis D. , Däweritz L. , Ploog K. H.
Published: April 2005

We report on the microstructure of (Ga,Mn)As digital ferromagnetic heterostructures grown on GaAs (001) substrates by low-temperature molecular-beam epitaxy. The Mn concentration and the As4∕Ga beam equivalent pressure (BEP) ratio are varied in the samples containing periods of Mn sheets separated by thin GaAs spacer layers. Transmission electron microscopy studies reveal that decreasing the Mn doping concentration and reducing the BEP ratio lead to smaller composition fluctuations of Mn and more homogeneous (Ga,Mn)As layers with abrupt interfaces. Planar defects are found as the dominant defect in these heterostructures and their density is related to the magnitude of the composition fluctuation. These defects show a noticeable anisotropy in the morphologic distribution parallel to the orthogonal [110] and [11¯0] direction. Along the [11¯0] direction, they are stacking faults, which are preferentially formed in V-shaped pairs and nucleate at the interfaces between (Ga,Mn)As and GaAs layers. Along the [110] direction, the planar defects are isolated thin twin lamellae. The character of the planar defects and their configuration are analyzed in detail.
Low-temperature Al-induced crystallization of amorphous Ge
Authors: Zanatta A. R. , Chambouleyron I.
Published: April 2005

This work reports on the low-temperature crystallization of hydrogenated amorphous germanium (a-Ge:H) films induced by aluminum. A series of aluminum-doped a-Ge:H films ([Al∕Ge]∼10−6–10−2 range) were deposited onto crystalline silicon substrates at 220°C by the cosputtering technique under the same nominal conditions, except for the Al∕Ge concentration. Raman scattering and infrared transmission spectroscopy were used for the structural characterization. The analysis of experimental data indicates that as-deposited Al-doped a-Ge:H films having an Al relative concentration between 1 and 2at.% crystallize spontaneously. Aluminum contents below this range induce a partial crystallization of the films, whereas [Al∕Ge]>2at.% does not induce any crystallization. The mechanisms involved in the crystallization of these Al-doped a-Ge:H films were also investigated after thermal annealing treatments up to a temperature of 500°C. Since the films are hydrogenated, the influence of hydrogen in the crystallization process was considered in detail. The ensemble of the data leads us to associate the induced crystallization with the coordination of, and the local order around, aluminum atoms in the a-Ge:H network. A microscopic mechanism behind the low-temperature crystallization is proposed. The present research indicates that both fourfold coordinated aluminum atoms and hydrogen species are fundamental in the crystallization phenomenon: the former acting as crystallization seeds, and the latter determining the dynamics of the process.
Local bonding environment of plasma deposited nitrogen-rich silicon nitride thin films
Authors: Soh Martin T. K. , Savvides N. , Musca Charles A. , Martyniuk Mariusz P. , Faraone Lorenzo
Published: April 2005

Plasma deposited nitrogen-rich silicon nitride thin films were prepared at temperatures between 80 and 300 °C. The infrared transmission (400–4000cm−1) was measured, and selected absorption bands were quantified through a multiple Lorentzian oscillator parametric analysis. It is observed that the concentration of silicon-centered tetrahedra bonded together through nitrogen atoms increases monotonically with increasing deposition temperature. A qualitative model is presented to highlight the impact of the active adsorption site density on the degree of stepped (ordered) nucleation at the vapor-film interface. The importance of this growth profile, in particular for micro-systems-technology, is discussed in conjunction with measurements of the biaxial modulus and residual stress of the thin films. A mechanism for residual stress controllability is also presented. The atomic concentrations of silicon, nitrogen, and hydrogen in the thin films were calculated using infrared calibration factors derived from the deposition temperature dependent condensation processes. The results for silicon nitride thin films deposited at 300 °C were observed to be similar in composition to silicon diimide. Additional observations of the infrared transmission characteristics are reported, which include the identification of silazane bridge characteristics for the absorption feature around 610cm−1, which is typically associated with Si–H (bending) absorption.
Electronic properties of half metallic Fe3O4 films
Authors: Jain S. , Adeyeye A. O. , Boothroyd C. B.
Published: April 2005

A systematic study of the electronic properties of Fe3O4 films grown directly on Si(001) substrates and on Ta, Ti, and SiO2 buffer layers using electron beam deposition is presented. The effect of the buffer layer on the Verwey transition temperature and on the current–voltage characteristics of Fe3O4 has been studied in detail. We observed that for a fixed Fe3O4 film thickness, the Verwey transition temperature is strongly dependent on the buffer layer materials. Transmission electron microscopy reveals that the growth mechanism of the Fe3O4 films is strongly dependent on the type of buffer layer used. The contribution of long range and short range charge ordering below the transition temperature has also been investigated. We observed an insulator-like gap structure in the density of states below the transition temperature which gradually disappears with increasing temperature.
Electron wave-packet transport through nanoscale semiconductor device in time domain
Authors: Fu Y. , Willander M.
Published: April 2005

Future low-power downscaled metal-oxide-semiconductor (MOS) devices are in a size regime that requires a quantum-mechanical approach. Two theoretical approaches, the steady-state single plane-wave transport model and the time-dependent wave-packet transport model, have been discussed to study the electron transport through model nanoscale potential profiles. It has been shown that the single plane-wave transport model at steady state neglects the coupling among different plane waves induced by the potential profile variation induced by the external bias. Thus, the model is only valid when the external bias is rather small. The electron wave-packet transport theory models the electrons by wave packets consisting of all available plane waves in the contact from where the electrons originate. The couplings among different plane waves are included in the temporal evolution of the time-dependent Schrödinger equation. This model is thus more proper when studying nanoscale devices at normal device working configurations. The effects of gate bias and the device geometry on the wave-packet transport are then studied by model potentials of future downscaled devices, which explains the experimentally reported conventional I−V characteristics of nanoscale MOS field-effect transistors (MOSFETs) at room temperature, while the normal MOSFET functioning is expected to be impossible by the single plane-wave transport model due to the independent tunneling effects of individual plane waves.
Modeling of electron mobility in GaN materials
Authors: Abdel-Motaleb Ibrahim M. , Korotkov Roman Y.
Published: April 2005

An analytical model for electron mobility in GaN has been developed. Scatterings due to ionized impurities, dislocations, acoustic phonons, and optical phonons were considered. The proposed model can accurately predict the electron mobility as a function of both the carrier concentration and the temperature. Results from this model were compared with the experimental results obtained from samples grown using metal-organic chemical-vapor deposition, molecular-beam epitaxy, and magnetron sputter epitaxy. The results show that this model can accurately predict the behavior of the mobility in GaN samples grown by different growth processes.
Strain compensation in boron-indium coimplanted laser thermal processed silicon
Authors: Clark Mark H. , Jones Kevin S.
Published: April 2005

Strain in B-implanted laser thermal processed (LTP) silicon is reduced by coimplantation of In. Strain in the codoped layer is calculated using lattice constants measured by high-resolution x-ray diffraction. Compensation of the strain with increasing In dose corresponds to suppression of the carrier deactivation during post-LTP annealing.
Characterization of the rapid expansion of supercritical solutions by Fourier transform infrared spectroscopy in situ
Authors: Bonnamy Anthony , Hermsdorf Dana , Ueberschaer Roman , Signorell Ruth
Published: April 2005

A new apparatus for the in situ characterization of the rapid expansion of supercritical solutions (RESS) by Fourier transform infrared spectroscopy is presented. The infrared characterization is complemented by particle sizing with a scanning mobility particle sizer, by three-wavelengths-extinction measurements, and by scanning electron microscopy. Several examples show that a wide range of information about particle properties can be obtained with this setup. One new aspect is the possibility to expand into the vacuum which also allows us to investigate the conditions in the collision-free region before the Mach disk. These investigations elucidate that in the free jet region the solvent CO2 condenses to particles with mean radii >50nm for pre-expansion pressures between 100–400bar and temperatures between 298–398K.
Calibration of Thomson scattering systems using electron cyclotron emission cutoff data
Authors: Zhurovich K. , Mossessian D. A. , Hughes J. W. , Hubbard A. E. , Irby J. H. , Marmar E. S.
Published: April 2005

An alternative method of absolute calibration of Thomson scattering (TS) systems is described. The method is based on the measurements of electron cyclotron emission (ECE) from the plasma. If the plasma density reaches some critical value the emission at some frequencies is cut off and an abrupt loss of signal is registered by the ECE diagnostic. These critical values are calculated from the frequencies of the ECE channels in which cutoffs are observed, using the dispersion relation for the wave propagation. The radial positions of the ECE channels are bound to the measured magnetic field in the tokamak and, therefore, are known. The derived critical density values at certain positions in plasma are used to calculate absolute calibration coefficients for the core TS system. For that data points from the TS diagnostic are interpolated in time and space to these critical density values. This calibration technique is implemented in situ on the Alcator C-Mod tokamak during plasma operation. We use a nine-channel ECE diagnostic to calibrate the eight-channel core TS system. The uncertainty of the TS density calibration is ⩽10%, which is less than that from the gas scattering calibrations. Good agreement exists between TS density profiles and measurements from the visible continuum diagnostic and interferometry. Given the wide availability of ECE diagnostics on most tokamaks and other fusion devices, this technique should be suitable on many other experiments.
Tracer-encapsulated pellet injector for plasma diagnostics
Authors: Sudo S. , Viniar I. , Lukin A. , Reznichenko P. , Umov A.
Published: April 2005

An injector for making solid hydrogen pellets around impurity cores has been developed for plasma transport study in large helical device. A technique has been employed for automatic loading carbon or polystyrene cores of 0.2 mm diameter from a gun magazine to a light-gas gun barrel. The injector is equipped with a cryocooler and is able to form a 3.2 mm long and 3 mm diameter cylindrical solid hydrogen pellet at 7–8 K with an impurity core in its center within 6 min and to inject it in the light-gas gun up to 1 km∕s.
Pick-up cell for cluster beam experiments
Authors: Moro Ramiro , Rabinovitch Roman , Kresin Vitaly V.
Published: April 2005

In experiments in which a cluster beam picks up guest molecules by passing through a cell, the detection efficiency may be limited because of cluster beam scattering by the molecular vapor. We present a modified pick-up cell design that reduces cluster deflections and thereby improves the detection of mixed clusters. Its performance is illustrated with the help of a beam of water clusters picking up amino-acid or heavy-water molecules.
Device with a self-aligned microgap for studying microscale flows
Authors: Yao Donggang , Xie Zhe , Zou Qian
Published: April 2005

With the increasing interest in pressure-driven liquid flows in confined geometries, there emerges a need for the development of suitable devices for microrheological studies. The standard rheometry with macrogaps, however, has inherent disadvantages in adapting itself into a microscale version. On the other hand, compliance-based apparatuses are inappropriate for high-shear flows because of their extremely low load capacity and small allowable strain and strain rate. In this article, a self-aligned device that involves a pair of parallel disks with the bottom one fixed and the top one floated is presented. A concentrated load is applied at the center of the floating plate, for adjusting the gap size and centering the top plate. The applied load is balanced by the upward force inside the liquid film resulting from viscous flow. Due to the complete axisymmetry in terms of the geometry and the stress field, the top plate will be self-aligned in reference to the bottom plate. The self-alignment mechanism and the design principle of the device were verified using experiments with water as a testing liquid.
Leak detection in spacecraft using structure-borne noise with distributed sensors
Authors: Holland Stephen D. , Roberts Ron , Chimenti D. E. , Strei Michael
Published: April 2005

We have developed and tested in the laboratory a method for in-orbit detection and location of air leaks in manned spacecraft that uses only a small number of sensors distributed arbitrarily on the inner surface of the spacecraft skin. Then, structure-borne ultrasound in the range of 300–600 kHz is monitored from each of the sensors. When cross correlations between measured sensor waveforms indicate the presence of a leak, these correlations are compared with a large dynamically generated database of simulated correlations to locate the the leak on the pressure vessel. A series of experimental tests were performed and at worst the method identified some false locations, but the true location of the leak always appeared.
Impact of Hf content on negative bias temperature instabilities in HfSiON-based gate stacks
Authors: Houssa M. , Aoulaiche M. , Van Elshocht S. , De Gendt S. , Groeseneken G. , Heyns M. M.
Published: April 2005

The shift of the threshold voltage, Vth, of p-channel metal-oxide-semiconductor field-effect transistors with HfSiON gate stacks, subjected to negative bias temperature stress, is investigated. It is found that Vth shift increases with time, like a power law, with an exponent that decreases with the amount of Hf in the HfSiON layer. Within the reaction-diffusion model for negative bias temperature instabilities, this finding suggests that the transport of hydrogen species in the gate stack is slower (i.e., more dispersive) in Hf-rich silicate layers. This result is also consistent with the observed increase in activation energy related to the hopping of the species in the gate stack with the Hf content, extracted from the temperature acceleration of Vth shifts. It is also found that negative bias temperature instabilities are reduced in layers with Hf content of about 50 at. %. This “optimum” is tentatively attributed to the interplay between the slower transport of the hydrogen species and the larger density of interface and bulk defects in the gate stack when the Hf content increases.
Stationary entanglement of atoms induced by classical field
Authors: Çakir Özgür , Klyachko Alexander A. , Shumovsky Alexander S.
Published: April 2005

We propose a scheme of stabilization of high-level entanglement through the use of classical driving field in atomic system with dipole-dipole interaction and losses caused by spontaneous radiation processes.
Analytical investigations on breakup of viscous liquid droplets on surface tension modulation during welding metal transfer
Authors: Chakraborty Suman
Published: April 2005

Viscous jets of a molten metal ready to be transferred into the arc welding pools are inherently unstable, and the associated droplet formation can be influenced by modulation of surface tension forces, which are strong functions of variations of temperature and surfactant composition. This principle can be effectively used to augment transfer rates, especially in microwelding situations. The present work deals with development of closed-formed mathematical expressions directly depicting various modes of the associated capillary instabilities. The analytical form of the final solution depicts a variation of time required for droplet formation as a function of the surface tension modulation, corresponding to different instability modes.
Ferroelectric response from lead zirconate titanate thin films prepared directly on low-resistivity copper substrates
Authors: Losego Mark D. , Jimison Leslie H. , Ihlefeld Jon F. , Maria Jon-Paul
Published: April 2005

We demonstrate films of the well-known ferroelectric lead zirconate titanate (PZT) prepared directly on copper foils by chemical solution deposition (CSD). The films exhibit saturating polarization hysteresis, remanent polarization values of 26μC∕cm2, and permittivities of 800; these properties are comparable to those achieved using semiconductor-grade substrates. The preparation methodology is founded upon an understanding of solution chemistry as opposed to conventional gas-phase ∕ condensed-phase equilibrium approaches. By adopting this technique, base-metal compatibility can be achieved using much lower temperatures, and a broader set of devices can be prepared offering intimate contact with high conductivity, easily patternable, or ferromagnetic metals.
Interface defects in Si∕HfO2-based metal-oxide-semiconductor field-effect transistors
Authors: Pribicko T. G. , Campbell J. P. , Lenahan P. M. , Tsai W. , Kerber A.
Published: April 2005

Using spin dependent recombination (SDR), we observe the generation of Pb-like center Si∕HfO2 interface trapping defects resulting from gate voltage stressing in fully processed metal gate transistors. We find that in situ gate voltage stressing increases the amplitude of the SDR response of the Si∕HfO2 interface Pb-like defect. A sequence of modest negative and positive voltages produces hysteretic behavior in the SDR response. This result suggests that the application of modest gate voltages changes the chemical∕physical nature of the defects involved.
Anomalous interfacial diffusion in immiscible metallic multilayers: a size-dependent kinetic approach
Authors: Ouyang G. , Wang C. X. , Yang G. W.
Published: April 2005

In order to gain a better understanding of the interfacial alloying in binary immiscible metallic mutilayers, we established a size-dependent kinetic model to address the diffusion that takes place at the interface in the immiscible metallic bilayer on nanoscale, and found an abnormal interfacial diffusion behavior when the diffusion length less than 2 nm. The nanosize-dependent diffusion coefficients of binary immiscible metals in bilayers were predicted on the basis of the proposed model. Taking the Cu–Ta multilayers as an example, we showed that these theoretical predictions are in agreement with experiments and computational simulations.
Terahertz gain in optically excited biased semiconductor superlattices
Authors: Zhang Aizhen , Wang Dawei , Dignam M. M.
Published: April 2005

We investigate the terahertz-driven dynamics of excitons in an undoped optically excited biased semiconductor superlattice, including exciton-LO phonon scattering. We calculate the THz gain spectrum for a 820fsTHz pulse when the superlattice is excited by a 590fs optical pulse. The gain arises because, in contrast to the single-electron case, the excitonic Wannier-Stark ladder is asymmetric with respect to absorption and emission. We find that gain coefficients greater than 100cm−1 can be achieved at excitation densities for which domain formation should not occur.
Functional Analysis of Human Microtubule-based Motor Proteins, the Kinesins and Dyneins, in Mitosis/Cytokinesis Using RNA Interference
Authors: Zhu Changjun , Zhao Jian , Bibikova Marina , Leverson Joel D. , Bossy-Wetzel Ella , Fan Jian-Bing , Abraham Robert T. , Jiang Wei
Published: April 2005

Microtubule (MT)-based motor proteins, kinesins and dyneins, play important roles in multiple cellular processes including cell division. In this study, we describe the generation and use of an Escherichia coli RNase III-prepared human kinesin/dynein esiRNA library to systematically analyze the functions of all human kinesin/dynein MT motor proteins. Our results indicate that at least 12 kinesins are involved in mitosis and cytokinesis. Eg5 (a member of the kinesin-5 family), Kif2A (a member of the kinesin-13 family), and KifC1 (a member of the kinesin-14 family) are crucial for spindle formation; KifC1, MCAK (a member of the kinesin-13 family), CENP-E (a member of the kinesin-7 family), Kif14 (a member of the kinesin-3 family), Kif18 (a member of the kinesin-8 family), and Kid (a member of the kinesin-10 family) are required for chromosome congression and alignment; Kif4A and Kif4B (members of the kinesin-4 family) have roles in anaphase spindle dynamics; and Kif4A, Kif4B, MKLP1, and MKLP2 (members of the kinesin-6 family) are essential for cytokinesis. Using immunofluorescence analysis, time-lapse microscopy, and rescue experiments, we investigate the roles of these 12 kinesins in detail.
Magic and the Regulation of Reason
Authors: Styers Randall G.
Published: April 2005

This chapter examines the scholarly literature in which magic is defined as faulty or inchoate science. The chapter begins by examining early theoretical constructions of the “primitive”; irrational (or pre-rational) magical thought was seen by numerous early anthropologists and sociologists as a definitive index of the superstitious primitive mind. While the notion of the “primitive” has become intellectually untenable, magic nonetheless retains a central role in subsequent discussions of the nature and limits of modern rationality (often standing as shorthand for non-modern mental and social processes). Finally, the chapter moves to explore recent disputes among historians over the role of medieval natural magic in the emergence of early modern science. Positioned at (or beyond) the boundary of rationality, magic serves both as the foil against which distinctive forms of Western science are defined and as the decisive test of scientific rationality's ability to explain the irrational.
Introduction
Authors: Dicker Georges
Published: April 2005

This chapter discusses Kant’s relation to Rationalism and Empiricism, his attempt to reduce his agenda to the issue of synthetic a priori judgments, and the overall of plan and structure of the Critique of Pure Reason.
Appendix
Authors: Dicker Georges
Published: April 2005

The appendix expounds Kant’s theory of schematism. The topic is introduced in relation to Locke’s attempt to explain what justifies applying a concept to instances and Berkeley and Hume’s responses to Locke. Against this background, Kant’s theory is analyzed as an attempt to explain what justifies applying a pure concept, like the concept of cause, to its instances. The appendix ends by discussing the relation of the schematism to broader aspects of Kant’s critical philosophy.
Causal Explanation: Background and Criticism
Authors: Woodward James
Published: April 2005

This chapter explores the philosophical background to the notion of causal explanation, focusing on the Deductive-Nomological Model of explanation and the role of laws in explanation and in causal claims. A number of different theses about the role of laws are distinguished: the thesis that at least one law underlies every true causal or explanatory claim, the semantic thesis that all causal claims entail the existence of laws, in virtue of their meaning, the epistemological thesis that knowledge of laws is necessary for establishing causal claims, and the explanation thesis that laws are part of every acceptable causal explanation. Only the first “underlying” thesis is defensible.
IT Governance
Authors: Luftman Jerry N.
Published: April 2005

IT governance describes how the processes and authority for resources, risk, conflict resolution, and IT responsibility are shared among business partners, IT management, and services providers. The lack of governance affects the organization’s ability to make informed decisions about the direction and use of it. The relationship between the team (business and IT) participating in the six-step process for defining the IT strategy should be continued as the IT executive steering committee.
Introduction
Authors: Bianchi Robert R.
Published: April 2005

The hajj has always had far-reaching political ramifications, but today, after a half century of sponsorship and regulation by governments around the world, it is more politicized than ever. In most countries, hajj administration is tainted with favoritism and corruption. All the major pilgrimage programs are explicitly tailored to benefit voting blocks and businesses at home while cultivating prestige and influence abroad. Frequently, pilgrim management is so politicized it subverts the central values of the hajj. Instead of promoting unity and equality, it divides Muslims along every conceivable line–ethnicity, language, class, party, region, sect, gender, and age.
Pakistan
Authors: Bianchi Robert R.
Published: April 2005

Hajj growth closely tracks the power struggles and ideological shifts that shaped and demolished Pakistan’s political regimes. Zulfikar Ali Bhutto and his Pakistan People’s Party helped to invent modern hajj management, spreading its benefits across all regions and ethnic groups in order to gain support from voters who were skeptical of his Islamic credentials. Zia-ul-Haq supported a smaller hajj that favored Punjabi and Pashtun groups who prospered the most from his dictatorship. Benazir Bhutto used state-sponsored pilgrimage to build a nationwide coalition of voters from many regions and sects, including women from families that usually supported the Pakistan Muslim League of her main rival, Nawaz Sharif. Nonetheless, control over the hajj does not give politicians control over the hajjis because many Pakistanis believe that in an Islamic state every government has a duty to support pilgrimage no matter what its ideology or economic policy.
Malaysia
Authors: Bianchi Robert R.
Published: April 2005

Malaysia’s leaders have nurtured the state hajj agency, Tabung Haji, into an internationally applauded experiment to spur modern capitalism with the aid of traditional religious values. Pilgrimage not only fosters economic development, it also helps centrist Malay politicians dominate their Chinese partners in the ruling alliance, the Barisan Nasional, and to weaken the appeal of radical Islamic rivals in the major opposition party, PAS. However, the very political prominence that allowed the hajj agency to thrive for nearly forty years is crippling it today. Tabung Haji has become such an effective instrument of the ascendant Malay elite that it now exacerbates the same conflicts of race, class, and region that plague the nation as a whole.
Biblical Myth and Rabbinic Mythmaking
Authors: Fishbane Michael
Published: April 2005

This book aims to retrieve, study, and reconstruct the phenomenon of monotheistic myth over the course of two millennia, from its first literary articulations in the Hebrew Bible to mythmaking in classic rabbinic Midrash and the medieval Kabbalistic book of Zohar. Several paradigmatic configurations are isolated and used to explore the characters and construction of monotheistic myth sources, and patterns of thermatic continuity and transformation. This strategy will allow a synchronic analysis of central tropics in each separate period and facilitate their diachronic correlation and comparison with various corpora. The book is divided into three parts. Part I deals with biblical myths. Part II focuses on Rabbinic myth and mythmaking. Part III explores Jewish Myth and Mythmaking in the Middle Ages.
The Passive Leverage of the European Union
Authors: Vachudova Milada Anna
Published: April 2005

This chapter presents a theoretical framework for the EU’s passive leverage, defined as the traction that the EU has on the domestic politics of credible candidate states merely by virtue of its existence and its usual conduct. Passive leverage includes the political and economic benefits of EU membership, the costs of exclusion, and the way that the EU treats non-member states. The force of the EU’s passive leverage explains why the governments of virtually all credible future EU member states declare EU membership as their foremost foreign policy goal.
Introduction
Authors: Rodin David
Published: April 2005

This introductory chapter discusses the rationale behind the arguments on self-defence presented this volume, specifically, self-defence as a moral response to war and aggression. It is argued that a coherent explanation of self-defence can be constructed around the idea of personal rights. However, the attempt to build a justification for war on the conception of self-defence faces significant obstacles and ultimately fails.
A Model of Defensive Rights
Authors: Rodin David
Published: April 2005

Hohfeld treats liberties as a normative relation between three elements: subject (the party who possesses the liberty), content (what the subject has a liberty to do), and object (the party with respect to whom the liberty is held). This chapter develops a working explanatory model of defensive rights by adding to these three elements a so-called end of a defensive right, defined as the good or value which a defensive action is intended to preserve or protect. Two of three legs that constitute the justification of self-defence are explored: those that revolve around the relationship between subject and the end of the right, and those that concern the relationship between the content (defensive action) and the end of the right.
Consequences and Forced Choice
Authors: Rodin David
Published: April 2005

This chapter presents the third and final leg of a model of defensive rights discussed in the preceding chapter. It explores the ‘moral asymmetry’ problem between defender and aggressor — why the defender is justified in killing an aggressor but not vice versa. It presents specific objections to the initially promising account of self-defence as a forced choice. It argues that an explanation of self-defence cannot be found in the realm of reduced responsibility and necessity. When one kills in self-defence, one is responsible for one’s killing; if the act escapes condemnation, then it must be because killing is, in the circumstances, rightful.
Grounding Self-Defense in Rights
Authors: Rodin David
Published: April 2005

This chapter presents a rights-based explanation of self-defence. A right of defence exists when a subject is at liberty to defend a certain good by performing an action that would otherwise be impermissible. The moral justification for this liberty invokes three considerations: an appropriate normative relation exists between the subject and the end of the right, consisting of either of a right to, or a duty of care towards the good protected; the defensive act is a proportionate, necessary response to an imminent threat of harm; and the object of defensive force has an appropriate degree of normative responsibility for, and the subject is innocent of, the harm threatened.
The Constructivist Challenge 2
Authors: Shafer-Landau Russ
Published: April 2005

Examines the challenges to moral realism posed by constructivism. Poses a central challenge to constructivism: the initial constraints that define the context of choice for the agents whose responses are determinative of moral reality are either moralized or are not. If the former, then constructivism presupposes moral realism. If the latter, we have no good reason for thinking that the relevant constructors are really well suited to their task.
Catholicism
Authors: O'Collins SJ Gerald , Farrugia SJ Mario
Published: April 2005

After two chapters on the rise and history of Catholic Christianity, the authors explain systematically how the beliefs and practices of Catholicism came to be what they are. A chapter on revelation, tradition, and scripture introduces six chapters, which set out Catholic doctrines in the order in which they developed: the Trinity and the Incarnation; sin, the life of grace, and the promise of glory; the seven sacraments; the nature of the Church and its mission; and Catholic moral life and teaching. The book ends by drawing together major characteristics of Catholic Christianity and setting out some central challenges, that the Catholic Church now faces. The central aim of the book is to present, with ecumenical sensitivity, the world’s oldest and largest institution, the Roman Catholic Church.
The First Thousand Years
Authors: O'Collins SJ Gerald , Farrugia SJ Mario
Published: April 2005

This chapter first examines the Church’s spread in the post-Pentecost situation, its early leadership, the persecutions, and the enduring contributions of Justin, Irenaeus, Tertullian, Origen, and Cyprian. In 312, the Emperor Constantine brought public freedom to Christianity and initiated the story of the seven general councils, which settled Catholic faith in Christ and the Trinity. The chapter ends by tracing the further spread of the Church, the rise of monasticism and doctrinal developments down to 1054, the year conventionally used to date the break between Eastern and Western Christianity.
The Sensory Classification Thesis
Authors: Matthen Mohan
Published: April 2005

Sensory systems are automatic sorting machines which assign external sensed objects (distal stimuli) to classes on the basis of useful commonalities found in them. The results of a system=s sorting activities are made available to the perceiver in the form of a sensation, which can be held in memory or later recalled. Appearance thus follows classification as the record thereof. It follows (a) that sensory qualities are prior to experience and hence cannot be defined in terms of it, and (b) that all variations in the appearance of the stimulus are representationally significant (but not that all phenomenal variation is representationally significant).
Sense Experience
Authors: Matthen Mohan
Published: April 2005

This chapter examines the role and character of sensory experience. Sensory classification can lead to action by means of direct manipulation of the effector system; when this is so, the output of the sensory system must be causally apt to coerce the effector system. However, either when a sensory system feeds into many effector systems, or when many sensory systems feed into a single effector, it is simpler for the sensory systems to be non-coercive. Their output will simply signal that a particular situation obtains, leaving the effector system to do whatever it determines to be appropriate. In order to issue such signals, non-coercive systems need as many signs as there are response-demanding situations. In conscious systems, sensory qualia play this role. In the sense developed by David Lewis, it is a matter of convention which quale attaches to which state of affairs. The conventionality of sensory content is overlooked by philosophers who allege an Aexplanatory gap@ with regard to sensory qualia.
Hegel and Christian Theology
Authors: Hodgson Peter C.
Published: April 2005

Hegel’s Lectures on the Philosophy of Religion is one of the most important resources from the nineteenth century for theology as it faces the challenges of modernity and postmodernity. A critical edition of these lectures was published in the 1980s, which makes possible a study of the text on a level of accuracy and insight hitherto unattainable. The present book (by the editor and translator of the critical edition) engages the speculative reconstruction of Christian theology that is accomplished by Hegel’s lectures, and it provides a close reading of the text as a whole. The first two chapters argue that Hegel’s philosophy of religion is a philosophical theology focused on the concept of spirit, and they provide an overview of his writings on religion prior to the philosophy of religion. The book analyses Hegel’s conception of the object and purpose of the philosophy of religion, his critique of the theology of his time, his approach to Christianity within the framework of the concept of religion, his concept of God, his reconstruction of central Christian themes (Trinity, creation, humanity, evil, Christ, Spirit, community), and his placing of Christianity among the religions of the world. The concluding chapter makes a case for the contemporary theological significance of Hegel by identifying currently contested sites of interpretation and their Hegelian resolution (focusing on the categories of spirit, wholeness, narrative, Christ, community, and pluralism). Hegel, it is argued, provides a basis for a revisioning of central doctrinal themes in contrast to the reigning dogmatisms of our time, namely philosophical agnosticism and religious fundamentalism. The book is being published concurrently with the reissuing by Oxford University Press of the Lectures on the Philosophy of Religion.