bluuebunny/crossref_metadata_2025 huggingface dataset:
Shakespeare's Visual Theatre: Staging the Personified Characters. By Frederick Kiefer. Cambridge: Cambridge University Press, 2003; pp. xiv + 358; 40 illus. $75 cloth.
Authors: De Ornellas Kevin
Published: October 2005

Frederick Kiefer's Shakespeare's Visual Theatre: Staging the Personified Characters is a deceptively modest study, focusing on staged abstract representations and deities such as Spring, Time, Juno, and Ceres: “walking, talking personifications” (13). Kiefer presents case studies of individual personifications in particular plays, always speculating on their appearance in original stagings, and, most important, stressing their significance for contemporary and subsequent readings of the action. In the process, he compellingly argues for the significance of spectacle in Shakespeare's theatre. Though the length of the book might seem daunting, 138 pages are composed solely of impeccable notes, a meaty bibliography, and a useful index. The well-illustrated 220 pages of actual text are clear, jargon-free, learned, and convincing.
Jump Jim Crow: Lost Plays, Lyrics and Street Prose of the First Atlantic Popular Culture. Edited by W. T. Lhamon. Cambridge, MA: Harvard University Press, 2003; pp. 459. $39.95 cloth.
Authors: Roark Kate
Published: October 2005

As the first published collection of early blackface-performance texts, W. T. Lhamon's Jump Jim Crow: Lost Plays, Lyrics, and Street Prose of the First Atlantic Popular Culture provides scholars of American popular entertainment with a much-needed sourcebook. These texts are collected in service of the book's larger purpose of evaluating the career of Thomas Dartmouth “Daddy” Rice, the first superstar of blackface performance, who became synonymous with his most popular character, Jim Crow. All the songs and plays gathered in Jump Jim Crow were performed by Rice (with the exception of the “street prose” section, which includes two contemporary, pamphlet biographies of Rice). The texts work with Lhamon's introduction to tell the story of Rice's career, which is a case study of the larger topic: the history of blackface performance before the rise of the minstrel show in the mid-1840s. As the plays collected here reveal, Rice's performance of blackface was fundamentally different from minstrel-show performance on many levels. The most important difference, Lhamon argues in his introduction, is that Rice's performances encouraged the white audience to identify with his blackface character, to laugh with him rather than at him.
A robust motion design technique for flexible-jointed manipulation systems
Authors: Alici Gürsel , Kapucu Sadettin , Bayseç Sedat
Published: October 2005

This paper presents a robust input shaping technique that significantly reduces (almost eliminates) the residual vibration of manipulation systems typified by a flexible-jointed robot manipulator. The technique consists of two stages. In the first stage, a ramp function is superimposed onto the main trajectory to be preshaped. In the second stage, the outcome of the first stage is convolved with a sequence of two impulses. The robustness of the technique to the uncertainties in the system natural frequency and damping ratio are quantified through simulation and experimental evaluation. Simulation and experimental results demonstrate that the technique is not only effective in reducing the residual vibrations, but also it is robust to the uncertainties of as ∓35% from the ideal value of the system natural frequency. Further, it has been found that the proposed input shaping technique is insensitive to the uncertainties in the damping ratio. The results allow us to suggest that the proposed technique is versatile and robust enough to apply it to the motion design of any flexible-jointed manipulation system making a point-to-point motion.
Robust and adaptive control of three dimensional revolute-jointed cooperative manipulators for handling automation
Authors: Sarikaya Hürvet , Burkan Recep , Uzmay İbrahim
Published: October 2005

This paper presents a study of the application of adaptive and robust control methods to a cooperative manipulation system which is developed for handling an object by three dimensional revolute-jointed manipulators. The adaptive control algorithm supports the parameter adaptive law that provides guaranteed stability for uncertain systems. In designing the robust control structure, contact and friction constraints for grasp and bearing conditions, structural flexibility or such similar factors as various unmodeled dynamics are considered as uncertainties that determine available values of control parameters. The novelty of results in the present paper is to define new control inputs using parametric uncertainties and the Lyapunov based theory of guaranteed stability of uncertain systems for handling objects in a spatial workspace.
Trajectory optimization of flexible mobile manipulators
Authors: Ghariblu H. , Korayem M. H.
Published: October 2005

A computational algorithm is developed to find a dynamic motion trajectory of a mobile manipulator with flexible links and joints that will allow the robot to carry a maximum load between two specified end positions. A compact form of the linearized state space dynamic equations is organized as well as constraint equations. Then, the problem of finding a maximum load carrying capacity on flexible mobile manipulators is formulated as a trajectory optimization problem.
Contractility–afterload mismatch after the Fontan operation
Authors: Szabó Gábor , Bährle Susanne
Published: October 2005

During the past decades, different variants of the Fontan circulation have become the primary therapeutic option for physiological correction of congenital cardiac malformations in which restoration to biventricular circulations is impossible. Subsequent to creation of the Fontan circulation, the pulmonary and systemic circulations are in series, with only one pumping chamber. Thus, the functionally single ventricle must provide energy for flow of blood to the lungs, as well as to the body. Generally, patients who have undergone these procedures have a good prognosis, although they have subnormal cardiac output at rest, while their central venous pressure is significantly elevated. Despite an adequate haemodynamic situation at rest, exercise performance is usually reduced. Thus far, this reduction has been attributed to cardiac factors, such as the absence of the morphologically right ventricle, or impaired function of the morphologically left ventricle. Due to the mechanical coupling between the heart and the peripheral circulation, however, the inadequate response to exercise in terms of cardiac output might also be dependant on insufficient peripheral vascular adjustments. In this review, we assess the existing experimental and clinical studies which provide detailed analysis of ventriculo-arterial mechanics in the setting of the Fontan circulation.
Findings from new echocardiographic techniques concerning ventricular remodelling and function in the functionally univentricular heart
Authors: Pacileo Giuseppe , Di Salvo Giovanni , Rea Alessandra , Calabrò Raffaele
Published: October 2005

Those patients with functionally univentricular hearts are the ones in which surgical repair so as to produce biventricular circulations is deemed impossible, despite the fact that in most instances there are two ventricles within the ventricular mass. Before the era of the Fontan procedure, the typical course of patients with such functionally univentricular arrangements consisted of cardiac failure and death within the first year of life. Despite the advent of effective palliative therapy, ventricular dysfunction remains a significant clinical problem for these patients.
The role of magnetic resonance imaging in the evaluation of the functionally single ventricle before and after conversion to the Fontan circulation
Authors: Festa Pierluigi , Ait Ali Lamia , Bernabei Massimo , De Marchi Daniele
Published: October 2005

Magnetic resonance imaging is a powerful diagnostic tool, able to give us accurate anatomical and functional insights concerning the structure of the heart, and capable of overcoming some of the drawbacks and limitations of echocardiography and catheterization. The aim of our current review is to highlight the advantages and applications of the technique in the evaluation of patients with functionally univentricular hearts before and after conversion to the Fontan circulation. Most of these patients will have undergone surgery several times in their life, with a certain body size, and with less than optimal echocardiographic windows because of the surgical scars. Moreover, vascular access is sometimes unavailable due to previous catheterizations. Furthermore, resonance imaging is non-invasive, and can be performed without sedation in patients older than 8 years. Since many of the current techniques, some of them still experimental, will be used extensively in future clinical practice, physicians should be aware of the full spectrum of capabilities of resonance imaging. We will highlight all these applications in the sections which follow.
ELVES: Ein computergestütztes Diagnostikum zur Erfassung der Effizienz von Teilprozessen des Leseverstehens
Authors: Richter Tobias , van Holt Nadine
Published: October 2005

Zusammenfassung. Lesekompetenz beruht auf der effizienten Bewältigung von Teilprozessen des Leseverstehens, wie sie in hierarchischen Modellen der Textverarbeitung unterschieden werden. ELVES (Effizienz des Leseverstehens bei Erwachsenen nach dem Strategiemodell) ist ein computergestütztes Instrument zur Messung von Lesefähigkeiten bei geübten erwachsenen Lesern/innen. Die 7 Subtests des Instruments erfassen über die simultane Berücksichtigung von Antwortrichtigkeit und Antwortlatenz die Effizienz hierarchieniedriger (mikrostruktureller) und hierarchiehoher (makrostruktureller) Teilprozesse des Lesens nach van Dijk und Kintsch (1983) . Vier Untersuchungen mit studentischen Probanden/innen (N = 232) dienten einer ersten Konstrukt- und Kriteriumsvalidierung. Anhand der Skaleninterkorrelationen und der Ergebnisse einer konfirmatorischen Faktorenanalyse ließ sich die angenommene Trennung hierarchieniedriger und hierarchiehoher Teilfähigkeiten belegen. Die Subtests des Instruments korrelierten mit der Leistung in klassischen Leseverständnistests aus zwei verschiedenen Inhaltsbereichen und mit Indikatoren der Situationsmodellgüte aus einer naturalistischen Leseaufgabe. Anhand von Testtexten zu verschiedenen Themen konnte gezeigt werden, dass die hierarchiehohen ELVES-Subtests domänenübergreifende Lesefähigkeitskomponenten erfassen, die nicht auf inhaltliches Vorwissen reduzierbar sind.
Entwicklung eines Instruments zur Erfassung des Selbstkonzepts junger Erwachsener
Authors: Schwanzer Andrea D. , Trautwein Ulrich , Lüdtke Oliver , Sydow Hubert
Published: October 2005

Zusammenfassung. Auf der Grundlage des Self Description Questionnaire (SDQ) III ( Marsh, 1992 ) wurde ein deutschsprachiges Instrument zur Erfassung des Selbstkonzepts junger Erwachsener entwickelt, das 16 Facetten des Selbstkonzepts mit jeweils vier Items erfasst. In drei Pilotierungsstudien (insgesamt N = 367) und einer Validierungsstudie (N = 4709) wurden Belege für die Güte des Instruments gefunden. Die internen Konsistenzen der Skalen lagen zwischen .62 und .94 (M = .80). Faktorenanalysen unterstützten die theoretisch angenommene Struktur der Skalen. Retest-Reliabilitäten für ein Zeitintervall von 6-8 Wochen lagen zwischen .68 und .91. Zusammenhänge mit Außenkriterien wie Schulnoten, beruflichen Interessen und Studienfachwahlen wiesen auf eine zufriedenstellende Validität der Skalen hin.
A comparison of hydrographically and optically derived mixed layer depths
Authors: Zawada David G. , Zaneveld J. Ronald V. , Boss Emmanuel , Gardner Wilford D. , Richardson Mary Jo , Mishonov Alexey V.
Published: October 2005

Efforts to understand and model the dynamics of the upper ocean would be significantly advanced given the ability to rapidly determine mixed layer depths (MLDs) over large regions. Remote sensing technologies are an ideal choice for achieving this goal. This study addresses the feasibility of estimating MLDs from optical properties. These properties are strongly influenced by suspended particle concentrations, which generally reach a maximum at pycnoclines. The premise therefore is to use a gradient in beam attenuation at 660 nm (c660) as a proxy for the depth of a particle‐scattering layer. Using a global data set collected during World Ocean Circulation Experiment cruises from 1988–1997, six algorithms were employed to compute MLDs from either density or temperature profiles. Given the absence of published optically based MLD algorithms, two new methods were developed that use c660 profiles to estimate the MLD. Intercomparison of the six hydrographically based algorithms revealed some significant disparities among the resulting MLD values. Comparisons between the hydrographical and optical approaches indicated a first‐order agreement between the MLDs based on the depths of gradient maxima for density and c660. When comparing various hydrographically based algorithms, other investigators reported that inherent fluctuations of the mixed layer depth limit the accuracy of its determination to 20 m. Using this benchmark, we found a ∼70% agreement between the best hydrographical‐optical algorithm pairings.
Interannual flow along the northern coast of the Gulf of Mexico
Authors: Li Jianke , Clarke Allan J.
Published: October 2005

Past work has shown that the interannual wind stress curl in the North Atlantic generates Rossby waves that reach the eastern U.S. coast and affect coastal sea level both there and along the northern coast of the Gulf of Mexico. Tide gauge and TOPEX/Poseidon satellite sea level height measurements show that this interannual signal penetrates all the way around the Gulf of Mexico shelf to the Yucatan Peninsula, with local alongshore interannual wind stress increasing the signal amplitude between Pensacola and the Texas‐Louisiana shelf. Satellite observations show the seaward spatial structure of the sea level and the associated geostrophic flow. In theory this flow should depend on the angle θ of the shelf edge with respect to due north and the Loop Current mean shelf edge flow. Off the northern boundary (θ ≈ 90°), in agreement with theory, the signal behaves as a coastal Kelvin wave, the sea level amplitude falling quickly away from the shelf edge with first baroclinic radius of deformation scale. Off the western boundary (θ ≈ 180°) the interannual sea level amplitude falls rapidly seaward of the shelf edge, consistent with short western boundary scales. However, off the eastern boundary (θ small) formed by the west coast of Florida, the fall in interannual sea level amplitude seaward of the shelf edge is inconsistent with long Rossby wave theory. Interannual geostrophic Gulf of Mexico shelf edge flows may reach amplitudes of the order of 10 cm s−1, but along shelf flow amplitudes are a few centimeters per second or less. Even so, weak shelf flows of interannual frequency can transport particles many hundreds of kilometers.
Direct constraints on Antarctic Peninsula Ice Sheet grounding events between 5.12 and 7.94 Ma
Authors: Bart Philip J. , Egan Dave , Warny Sophie A.
Published: October 2005

How has the Antarctic Ice Sheet responded to or influenced global climate change? This simple question has been difficult to address because the long‐term records of the ice sheet's fluctuations are poorly constrained with geologic data from Antarctica. Thus studies to date have not convincingly established how specific Antarctic Ice Sheet events correlate with climatic, eustatic, or other phenomena known from low‐latitude and deep‐sea records. This study focused on documenting the direct record of ice sheet advance and retreat to the Antarctic Peninsula's shelf edge. On the peninsula's outer shelf, seismic reflectors interpreted to be subglacial unconformities were correlated with published results from Ocean Drilling Program Leg 178. Lithologic and chronologic control at two drill sites provided ground truth for the seismic interpretation and the timing of the Antarctic Peninsula Ice Sheet grounding events. This synthesis showed that grounded ice advanced to the shelf edge on at least 12 occasions between 5.12 and 7.94 Ma.
Mechanisms for millennial‐scale global synchronization during the last glacial period
Authors: Timmermann A. , Krebs U. , Justino F. , Goosse H. , Ivanochko T.
Published: October 2005

Global climate during the last glacial period was punctuated by abrupt warmings and occasional pulses of freshwater into the North Atlantic that disrupted deepwater production. These massive freshwater pulses known as Heinrich events arose, in part, from instabilities within the Laurentide ice sheet. Paleoevidence from the North Atlantic suggests that these events altered the production of deep water and changed downstream climate throughout the Northern Hemisphere. In the tropical western Pacific sea, surface temperatures and salinity varied together with ocean and climate changes at high latitudes. Here we present results from coupled modeling experiments that shed light on a possible dynamical link between the North Atlantic Ocean and the western tropical Pacific. This link involves a global oceanic standing wave pattern brought about by millennial‐scale glacial density variations in the North Atlantic, atmospheric teleconnections triggered by meridional sea surface temperature gradients, and local air‐sea interactions. Furthermore, our modeling results are compared with hydrological records from the Cariaco basin, the Indian Ocean, the Sulu Sea, and northern Australia.
GLAS long‐range transport observation of the 2003 California forest fire plumes to the northeastern US
Authors: Hoff R. M. , Palm S. P. , Engel‐Cox J. A. , Spinhirne J.
Published: October 2005

In October 2003, a series of forest and brush fires in southern California burned an area of over 2750 km2 with plumes reaching up to 6 km in altitude over the Pacific Ocean. On October 27, 2003, the Santa Ana (foehn) conditions flowing westward out of the desert that fueled the combustion ceased and a portion of the smoke plumes turned and headed eastward. The Geoscience Laser Altimeter System (GLAS) on ICESat provided aerosol profiles of the smoke along numerous ICESat tracks acquired throughout the week following the reversal of the smoke plume. The GLAS observations place the height of the smoke aerosols at <7 km as the smoke moved eastward over North America. GLAS measurement cross‐sections often preceded or trailed the main smoke pulses by a few hours and capturing the four‐dimensional picture of this moving target was only possible by combining multiple sensor observations with back trajectory calculations.
Effects of the North Sea Caspian pattern on surface fluxes of Euro‐Asian‐Mediterranean seas
Authors: Gündüz Murat , Özsoy Emin
Published: October 2005

The influence of the North Sea Caspian Pattern (NCP) on marine basins of the Euro‐Asian‐Mediterranean region (Mediterranean, Black and Caspian Seas) is investigated by making use of Empirical Orthogonal Functions (EOF) analysis. The effect of the NCP on surface fluxes of momentum and heat, as well as on curl and divergence of wind stress is evident in all of the studied basins. In particular, the Aegean and southern Black Sea heat fluxes are significantly affected by NCP. The processes underlying the demonstrated effects of the NCP on the Mediterranean Sea deserve further attention, especially as they relate to the so‐called Eastern Mediterranean Transient (EMT), a recent event that resulted in abrupt changes in the marine climate.
Improved electron fluxes from the synchronous orbit particle analyzer
Authors: Cayton T. E. , Tuszewski M.
Published: October 2005

New electron responses have been evaluated for the synchronous orbit particle analyzer (SOPA) that Los Alamos National Laboratory flies on geosynchronous satellites. The new responses include for the first time a comprehensive treatment of bremsstrahlung photons, as well as actual dimensions and electronic noise. The new responses yield energetic (0.05–1.5 MeV) electron fluxes accurate to within a factor of 2. Whenever the electron energy spectra are sufficiently soft, the new electron fluxes agree reasonably well with previous estimates. However, for hard electron energy spectra often found after geomagnetically active times, significantly lower electron fluxes are obtained from the same observed counts. For such cases, previously obscured spectral features are clearly observed, and the plasma analyzer and SOPA electron fluxes show much better agreement.
Reduction of the Cell Cycle Length by Decreasing G1 Phase and Cell Cycle Reentry Expand Neuronal Progenitor Cells in the Subventricular Zone of Adult Rat after Stroke
Authors: Zhang Rui Lan , Zhang Zheng Gang , Lu Mei , Wang Ying , Yang James J , Chopp Michael
Published: October 2005

A critical determinant of proliferation of progenitor cells is the duration of the cell division cycle. Stroke increases proliferation of progenitor cells in the subventricular zone (SVZ). Using cumulative and single S-phase labeling with 5-bromo-2′-deoxyuridine, we examined cell cycle kinetics of neural progenitor cells in the SVZ after stroke. In nonstroke rats, 20% of the SVZ cell population was proliferating. However, stroke significantly increased dividing cells up to 31% and these cells had a cell cycle length ( Tc) of 15.3 h, significantly ( P < 0.05) shorter than the 19 h Tc in nonstroke SVZ cells. Few terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick end labeling-positive cells were detected in the SVZ cells of nonstroke and stroke groups, suggesting that the majority of dividing cells in the SVZ do not undergo apoptosis. Cell cycle phase analysis revealed that stroke substantially shortened the length of the G1 phase (9.6 h) compared with the G1 phase of 12.6 h in nonstroke SVZ cells ( P < 0.03). This reduction in G1 contributes to stroke-induced reduction of Tc because no significant changes were detected on the length of S, G2 and M phases between two groups. Furthermore, compared with progenitor cells in nonstroke SVZ (10%), a greater proportion (14%) of progenitor cells in stroke SVZ reentered the cell cycle after mitosis ( P < 0.05). These results show that an increase in proliferating progenitor cells in the SVZ contributes to stroke-induced neurogenesis and this increase is regulated by shortening the length of the cell cycle, decreasing the G1 phase and increasing cell cycle reentry.
Evaluation of Laser Speckle Flowmetry for Imaging Cortical Perfusion in Experimental Stroke Studies: Quantitation of Perfusion and Detection of Peri-Infarct Depolarisations
Authors: Strong Anthony J , Bezzina Elizabeth Lindsey , Anderson Peter JB , Boutelle Martyn G , Hopwood Sarah E , Dunn Andrew K
Published: October 2005

Laser speckle imaging of the exposed cerebral cortex allows detailed examination of the time course and topography of perfusion under different experimental conditions. Here we examine the quantitative capacity of the method and its sensitivity for the detection of peri-infarct depolarisations (PIDs). In four cats anaesthetised with chloralose, the right hemisphere was exposed and the right middle cerebral artery was occluded. The brain was illuminated with a laser diode, the speckle pattern was imaged, and images of inverse speckle correlation time (ICT) were derived from the calculated speckle contrast images. We examined the relationship of ICT with perfusion, as imaged quantitively using umbelliferone clearance (CBFumb). Values of ICT and CBFumb were compared and regression parameters were calculated for each experiment. In eight cats, cortical surface direct current (DC) potential was monitored at two locations and detection of PIDs by DC potential and ICT change was compared. ICT- and CBFumb-derived values of perfusion were closely correlated, with a high degree of significance ( P < 0.0001). Overall, monitoring of DC potential detected 90% of PIDs, whereas ICT detected 56%. We conclude that (1) laser speckle imaging provides an index of perfusion that has a linear relationship with the clearance rate of umbelliferone within the range of levels of perfusion examined; (2) this relationship is relatively stable between experiments; and (3) the method's ability to detect blood flow changes associated with PIDs likely depends on the noise level of the speckle measurements.
The vibrational energy pattern in acetylene VII: C12C13H2
Authors: Robert S. , Fayt A. , Di Lonardo G. , Fusina L. , Tamassia F. , Herman M.
Published: October 2005

In C12C13H2 129 vibrational term values up to 10000cm−1 are merged, about 60% of which are newly reported. They are fitted using an effective Hamiltonian with a standard deviation of 0.22cm−1. The vibrational assignments and vibrational constants are listed and discussed. The energy pattern is found to be very similar to the one in C212H2 with additional anharmonic resonances arising from the lack of u∕g character in the asymmetric isotopolog.
Weak metal-metal bonding in small manganese cluster ions, MnN+(N⩽7)
Authors: Tono Kensuke , Terasaki Akira , Ohta Toshiaki , Kondow Tamotsu
Published: October 2005

The binding energies of manganese cluster ions MnN+(N=5–7) were determined by the photodissociation experiments in the near-infrared and visible-photon-energy ranges. The bond dissociation energies of MnN+, D0(MnN−1+⋯Mn), were obtained to be 1.70±0.08, 1.04±0.10, and 1.46±0.11eV, respectively, for N=5, 6, and 7 from the threshold energies for the two-atom loss processes and the bond dissociation energies of Mn3+ and Mn4+ reported previously [A. Terasaki et al., J. Chem. Phys. 117, 7520 (2002)]. Correspondingly, binding energies per atom are obtained to be 0.99±0.03, 1.00±0.03, and 1.06±0.03eV∕at. for N=5, 6, and 7, respectively. A gradual increase in the binding energy from N=2 to N=7 shows an increasing contribution of nonbonding 3d orbitals to the bonding via weak hybridization with valence 4s orbitals as the cluster size increases. These binding energies per atom are still much smaller than the bulk cohesive energy of manganese (2.92eV∕at.), and this finding indicates exceptionally weak metal-metal bonds in this size range.
Energy band gaps and lattice parameters evaluated with the Heyd-Scuseria-Ernzerhof screened hybrid functional
Authors: Heyd Jochen , Peralta Juan E. , Scuseria Gustavo E. , Martin Richard L.
Published: October 2005

This work assesses the Heyd-Scuseria-Ernzerhof (HSE) screened Coulomb hybrid density functional for the prediction of lattice constants and band gaps using a set of 40 simple and binary semiconductors. An extensive analysis of both basis set and relativistic effects is given. Results are compared with established pure density functionals. For lattice constants, HSE outperforms local spin-density approximation (LSDA) with a mean absolute error (MAE) of 0.037 Å for HSE vs 0.047 Å for LSDA. For this specific test set, all pure functionals tested produce MAEs for band gaps of 1.0–1.3 eV, consistent with the very well-known fact that pure functionals severely underestimate this property. On the other hand, HSE yields a MAE smaller than 0.3 eV. Importantly, HSE correctly predicts semiconducting behavior in systems where pure functionals erroneously predict a metal, such as, for instance, Ge. The short-range nature of the exchange integrals involved in HSE calculations makes their computation notably faster than regular hybrid functionals. The current results, paired with earlier work, suggest that HSE is a fast and accurate alternative to established density functionals, especially for solid state calculations.
Nitrogen incorporation into GaInNAs lattice-matched to GaAs: The effects of growth temperature and thermal annealing
Authors: Pavelescu E.-M. , Wagner J. , Komsa H.-P. , Rantala T. T. , Dumitrescu M. , Pessa M.
Published: October 2005

We have studied the effects of growth temperature and subsequent thermal annealing on nitrogen incorporation into lattice-matched dilute Ga0.942In0.058NAs-on-GaAs epilayers, which were grown by the molecular-beam epitaxy method. The samples were studied experimentally by means of x-ray diffraction and Raman spectroscopy and theoretically by calculations within the density-functional theory. Over the entire range of growth temperatures applied (410–470°C), nitrogen appeared to be mainly located on substitutional sites in “short-range-order clusters” as N–Ga4 and, to a lesser extent, as N–Ga3In. There were also indications of the presence of nitrogen dimers NN, as suggested by Raman spectroscopy, in qualitative agreement with the calculations. An increase in growth temperature reduced the amount of substitutional nitrogen and decreased the number of N–Ga4 clusters relative to N–Ga3In. Postgrowth thermal annealing promoted the formation of In–N bonds and caused a blueshift in the optical band gap, which increased as the growth temperature was lowered.
Efficient white-light-emitting diodes based on polymer codoped with two phosphorescent dyes
Authors: Xu Yunhua , Peng Junbiao , Jiang Jiaxing , Xu Wei , Yang Wei , Cao Yong
Published: October 2005

Efficient white-light-emitting diodes (WPLEDs) based on a polymer codoped with two phosphorescent dyes were fabricated by the spin-casting method. Polyhedral oligomeric silsesquioxane-terminated poly(9,9-dioctylfluorene) (PFO-poss) was used as the host and blue light emitter. Phosphorescent emitters, fac-tris[2-(4′-ter-butyl)phenylpyridine] iridium (III) [Ir(Bu-ppy)3] and bis-(1-phenylisoquinolyl)iridium(III)(1-trifluoro) acetylacetonate [(Piq)2Ir(acaF)] with green and red emission, respectively, were used as the guests. The electroluminescence spectrum can be tuned by changing concentration of the guests. The structure of the WPLEDs is indium tin oxide (ITO)/poly(ethlenedioxythiophene):poly(styrene sulfonic acid) (PEDOT:PSS)/ PVK/PFO-poss codoped with Ir(Bu-ppy)3 and (Piq)2Ir(acaF)∕Ba∕Al. The PVK layer [poly(N-vinylcarbazole)] acts as the function of blocking electron penetrating from PFO-poss to PEDOT. When the doping concentrations are 0.14 wt % for both Ir(Bu-ppy)3 and (Piq)2Ir(acaF), the efficient white-light emission with CIE coordinates of around (0.33, 0.33) is achieved. The current efficiency reaches 5.5lm∕W (9cd∕A), and the maximum luminance of 10200cd∕m2 was gained at 11 V. The mechanisms of the WPLEDs with high efficiency are discussed.
Theoretical simulation and experimental study on resistivity properties of mixed-phase La2∕3Ca1∕3MnO3 thin films
Authors: Zhou Qing-li , Zhao Kun , Jin Kui-juan , Guan Dong-yi , Lu Hui-bin , Chen Zheng-hao , Yang Guo-zhen , Li Alan , Wong H. K.
Published: October 2005

The theoretical simulation and experimental study are reported on the metal-to-insulator transition, thermal hysteresis behavior, magnetic-field-induced reduction, and anisotropic characteristics of resistivity for La2∕3Ca1∕3MnO3 thin films deposited on SrTiO3 (001)-oriented substrates tilted by 10° towards the [010] direction. The simulated results obtained by using a random network model based on phase separation scenario are in quantitative agreement with our experimental data and indicate that tilting (applying magnetic field) can increase (decrease) the scatterings and the activation energy, resulting in enhancement (reduction) of resistivity. All those results suggest that the intrinsic inhomogeneity and the lattice structure play the significant roles in the electrical conductivity and anisotropic transport properties.
Interfacial waves due to a singularity in a system of two semi-infinite fluids
Authors: Lu D. Q. , Chwang Allen T.
Published: October 2005

The three-dimensional interfacial waves due to a fundamental singularity steadily moving in a system of two semi-infinite immiscible fluids of different densities are investigated analytically. The two fluids are assumed to be incompressible and homogenous. There are three systems to be considered: one with two inviscid fluids, one with an upper viscous and a lower inviscid fluid, and one with an upper inviscid and a lower viscous fluid. The Laplace equation is taken as the governing equation for inviscid flows while the steady Oseen equations are taken for viscous flows. The kinematic and dynamic conditions on the interface are linearized for small-amplitude waves. The singularity immersed above or beneath the interface is modeled as a simple source in the inviscid fluid while as an Oseenlet in the viscous fluid. Based on the integral solutions for the interfacial waves, the asymptotic representations of wave profiles in the far field are explicitly derived by means of Lighthill’s two-stage scheme. An analytical solution is presented for the density ratio at which the maximum wave amplitude occurs. The effects of density ratio, immersion depth, and viscosity on wave patterns are analytically expressed. It is found that the wavelength of interfacial waves is elongated in comparison with that of free-surface waves in a single fluid.
High-performance flexible zinc tin oxide field-effect transistors
Authors: Jackson W. B. , Hoffman R. L. , Herman G. S.
Published: October 2005

Flexible transistors were fabricated by sputter deposition of zinc tin oxide (ZTO) onto plasma-enhanced chemical vapor deposition gate dielectrics formed on flexible polyimide substrates with a blanket aluminum gate electrode. The flexible transistors exhibited high on-currents of 1mA, on/off ratios of 106, subthreshold voltage slopes of 1.6V/decade, turn-on voltages of −17V, and mobilities of 14cm2V−1s−1. Capacitance measurements indicate that the threshold voltage and subthreshold slope are primarily influenced by residual doping in the ZTO rather than by defects at the semiconductor/dielectric interface, and are useful for assessing contact resistance.
Directional Landau damping of wake-field potentials
Authors: Bose Anirban , Janaki M. S.
Published: October 2005

The wake-field potentials produced by charged particles moving in a plasma are investigated in the presence of finite Landau-damping effects in the wave dispersion relation. In the frame of reference moving with the particle, the phase velocities of the spectrum of waves excited by the moving charge depend on the angle of propagation of the wave vector giving rise to a directional wave-particle resonance condition. As a consequence, the wake structure is seen to decay both along and transverse to the direction of motion of the charged particle.
On-axis parallel ion speeds near mechanical and magnetic apertures in a helicon plasma device
Authors: Sun Xuan , Cohen S. A. , Scime Earl E. , Miah Mahmood
Published: October 2005

Using laser-induced fluorescence, measurements of parallel ion velocities were made along the axis of a helicon-generated Ar plasma column whose radius was modified by spatially separated mechanical and magnetic apertures. Ion acceleration to supersonic speeds was observed 0.1–5cm downstream of both aperture types, simultaneously generating two steady-state double layers (DLs) when both apertures were in place. The DL downstream of the mechanical aperture plate had a larger potential drop, ΔϕDL=6–9kTe, compared to the DL downstream of the magnetic aperture, ΔϕDL∼3kTe. In the presheath region upstream of the mechanical aperture, the convective ion speed increased over a collisional distance; from stagnant at 4cm from the aperture to the 1.4 times the sound speed at the aperture. The dependence of the free- and trapped-ion-velocity-distribution functions on the magnetic-field strength and mechanical-aperture electrical bias are also presented.
Polarization-independent phase modulation of a homeotropic liquid crystal gel
Authors: Ren Hongwen , Lin Yi-Hsin , Wen Chien-Hui , Wu Shin-Tson
Published: October 2005

A homeotropic liquid crystal (LC) gel with submicron domain size is fabricated and its phase-only modulation property evaluated. The LC gel is highly transparent in the voltage-off state and exhibits pure phase modulation before light scattering occurs. Compared to a nanosized polymer-dispersed liquid crystal (nano-PDLC), our gel possesses a larger phase change but at a lower operating voltage because of a higher LC concentration. Similar to a nano-PDLC, our gel also exhibit submillisecond response time, hysteresis-free, and polarization-independent phase change.
Characterization of a 90° waveguide bend using near-field scanning optical microscopy
Authors: Yuan Guangwei , Lear Kevin L. , Stephens Matthew D. , Dandy David S.
Published: October 2005

Multiple modes are directly imaged in a silicon nitride waveguide bend using near-field scanning optical microscopy. Since the high order mode attenuates faster than the fundamental mode, a transient interference is observed. Local loss at the bend-to-straight waveguide interface is found and attributed to modal mismatch. The observations are in good agreement with modal calculations using conformal index transformation.
Effect of heating rates on superconducting properties of pure MgB2, carbon nanotube- and nano-SiC-doped in situ MgB2∕Fe wires
Authors: Chen S. K. , Tan K. S. , Glowacki B. A. , Yeoh W. K. , Soltanian S. , Horvat J. , Dou S. X.
Published: October 2005

The influence of heating rates and annealing temperatures on the transition temperatures (Tc) and critical current densities (Jc) of pure MgB2, carbon nanotube- and nano-SiC-doped in situ monofilamentary MgB2∕Fe wires was investigated. It was found that higher Jc was obtained for pure MgB2 samples when heat treated with slower heating rates. SiC-doped samples also have higher Jc with slower heating rates, but the Jc is less sensitive to annealing temperatures. However, the Jc of the carbon nanotube-doped wire was found to be insensitive to heating rates. The variation in Tc and Jc with heating rate, and the different behaviors of differently doped MgB2∕Fe wires, make it essential to carefully select the optimum heating rates for heat treatment.
Self-sustained current oscillations in superlattices and the van der Pol equation
Authors: Sun Z. Z. , Yin Sun , Wang X. R. , Cao J. P. , Wang Y. P. , Wang Y. Q.
Published: October 2005

The connection between self-sustained current oscillations in superlattices and the famous van der Pol (vdP) equation is established by mapping a widely used model of self-sustained current oscillations to the vdP equation. Since this equation can describe an inductor-capacitor-resistor circuit with a nonlinear resistor of negative differential conductance, we have obtained an equivalent electric circuit for superlattices in the self-sustained current oscillation regime. The origin of the equivalent inductance of a superlattice is revealed.
GaInN quantum wells grown on facets of selectively grown GaN stripes
Authors: Neubert Barbara , Brückner Peter , Habel Frank , Scholz Ferdinand , Riemann Till , Christen Jürgen , Beer Martin , Zweck Joseph
Published: October 2005

Multiple GaInN quantum wells (QWs) were grown on facets with reduced piezoelectric fields (PFs) of selectively grown GaN stripes oriented along the ⟨11¯00⟩ and ⟨112¯0⟩ directions by metalorganic vapor phase epitaxy. We found a higher normalized growth rate for the GaInN QWs on the {11¯01} facets compared to the {112¯2} facets and the planar grown reference sample on unstructured template. The different luminescence wavelengths observed for the QWs on these different facets can partly be explained by the reduced PFs, but additionally indicate that the In incorporation efficiency depends on the facet type. On stripes with trapezoidal cross section, we found strong interfacet migration of In and Ga changing the local thickness and composition significantly.
Synthesis and postgrowth doping of silicon nanowires
Authors: Byon K. , Tham D. , Fischer J. E. , Johnson A. T.
Published: October 2005

High-quality silicon nanowires (SiNWs) were synthesized via a thermal evaporation method without the use of catalysts. Scanning electron microscopy and transmission electron microscopy showed that SiNWs were long and straight crystalline silicon with an oxide sheath. Field effect transistors were fabricated to investigate the electrical transport properties. Devices on as-grown material were p-channel with channel mobilities 1–10cm2V−1s−1. Postgrowth vapor doping with bismuth converted these to n-channel behavior.
Fighting Standards with Standards: Harmonization, Rents, and Social Accountability in Certified Agrofood Networks
Authors: Mutersbaugh Tad
Published: October 2005

In this paper I explore the remaking of globalized standards through harmonization, and its impact upon certified-organic and fair-trade agrofood networks. I focus on certification standards and discuss four shifts associated with globalized standards (an increased importance of multilateral institutions, changes to standards language, displacement of network-specific standards, and a shift away from relational standards). It is then argued, with reference to value-chain rent theory, that the shift to globalized standards has transformed rent relations in ways that benefit certain actors (that is, retailers) and imperil the earnings of others. In brief, globalized standards increase the costs of standards compliance, the full burden of which falls upon immiserated producers, to the point at which farmers see little economic advantage to certified-organic and fair-trade production. I then examine social-accountability standards that seek to ‘fight standards with standards’ by championing the consolidation of strong labor and environmental protections under a single label. The study suggests that a single-label strategy can be successful, yet must struggle to overcome a Polanyian double bind, for, in order to build broad coalitions necessary to extend the reach of protective standards, the coalitions must include corporate interests that prefer weaker, contract-based standards.
Role of winter-active aphids spreading Barley yellow dwarf virus in decreasing wheat yields in a Mediterranean-type environment
Authors: Thackray Deborah J. , Ward Laura T. , Thomas-Carroll Monica L. , Jones Roger A. C.
Published: October 2005

In the grainbelt of south-western Australia, which experiences Mediterranean-type climatic conditions, 3 field experiments with wheat were sown in autumn, 2 at Site A over 2 years and 1 at Site B in the first year only. These experiments related both activity of aphid vectors (migration into and colonisation of wheat) and the spread of infection with Barley yellow dwarf virus (BYDV) serotype PAV to wheat grain yield and quality. Incidences of BYDV serotype RMV and Cereal yellow dwarf (CYDV) were mostly low and BYDV serotype MAV was not distinguished. Rhopalosiphum padi was the predominant vector species but small numbers of R. maidis and Sitobion miscanthi were also present. Repeated insecticide spray applications began at different times in the different experimental treatments. These sprays killed or repelled aphid vectors, thereby preventing further virus spread from the time they were first applied. At both sites, migrant aphids were caught flying into the wheat throughout the winter period. Peak numbers of colonising aphids ranged from 0 to 99/0.5-m transect of crop. BYDV-PAV incidence ranged from 0.1 to 58% of plants and yields ranged from 1.9 to 8.6 t/ha. First aphid arrival was earlier, and virus spread and resulting yield losses greater at Site A. At this site, in treatments where repeated insecticide sprays did not start until 8 weeks after crop emergence (WAE), virus incidence and subsequent yield losses were significantly greater than when the regular applications started at emergence. However, delaying the start of sprays beyond 8 weeks had no further effect on virus spread. Since aphid numbers were very low up to 8–10 WAE, yield losses were due entirely to virus infection of plants during this early growth period. Variation in BYDV-PAV incidence explained 81 or 91% of the variation in yield gaps in the 2 years at Site A where, for each 1% increase in virus incidence, there was a yield decrease of 55 or 72 kg/ha. It also explained the variation in seed weight (88%) and protein content (69%), but not in seed screenings. At Site B, virus spread started too late to cause significant yield or quality losses. These results show that wheat yields are decreased substantially in a Mediterranean-type environment, when aphids immigrate early into wheat crops and remain active throughout the winter-growing period, spreading virus infection at young plant growth stages.
Corrigendum to: Highly sensitive DNA fingerprinting of orchid pollinaria remnants using AFLP
Authors: Indsto James O. , Weston Peter H. , Clements Mark A. , Whelan Robert J.
Published: October 2005

Numerous Australian terrestrial orchid species in the genus Diuris may be pollinated by food source mimicry. In our field studies, direct observations of orchid.pollinator interactions were rare, but native bees were frequently captured carrying orchid pollinaria, or pollinaria remnants. Sometimes, pollinaria remnants were minimal and included only the viscidium, a sticky pad that was often highly persistent. Confirmation of such tissue as being of orchid source, and attributing them to a particular species can aid pollination studies. DNA-based methods that may identify more or less intact orchid pollinaria are available, but extremely small and degraded samples can pose technical challenges. We have developed an AFLP protocol for such difficult samples that offers some significant advantages over direct PCR-based analysis. We simulated AFLP profiling of very low-DNA samples using DNA template from serial dilutions. A DNA sample range from 6.4 picograms to at least as high as 100 nanograms (15�500-fold range) all yielded AFLP fingerprints. The practical application of this inherent sensitivity of AFLP is demonstrated by the identification of remnants of orchid pollinaria sampled from bees, presented here as a case study. It is expected that this approach will find many applications where sample DNA is limiting, or possibly where pollen of similar appearance may comprise species mixtures.
The response of autologous T cells to a human melanoma is dominated by mutated neoantigens
Authors: Lennerz Volker , Fatho Martina , Gentilini Chiara , Frye Roy A. , Lifke Alexander , Ferel Dorothea , Wölfel Catherine , Huber Christoph , Wölfel Thomas
Published: October 2005

Our understanding of pathways leading to antitumor immunity may depend on an undistorted knowledge of the primary antigenic targets of patients' autologous T cell responses. In the melanoma model derived from patient DT, we applied cryopreserved short-term autologous mixed lymphocyte–tumor cell cultures (MLTCs) in combination with an IFN-γ enzyme-linked immunospot (ELISPOT) assay to cDNA expression screening. We identified three previously unknown peptides processed from melanosomal proteins tyrosinase (presented by HLA-A*2601 and -B*3801) and gp100 (presented by HLA-B*07021) and five neoantigens generated by somatic point mutations in the patient's melanoma. The mutations were found in the genes SIRT2, GPNMB, SNRP116, SNRPD1, and RBAF600. Peptides containing the mutated residues were presented by HLA-A*03011, -B*07021, and -B*3801. Mutation-induced functional impairment was so far demonstrated for SIRT2. Within MLTC responder populations that were independently expanded from the patient's peripheral blood lymphocytes of different years, T cells against mutated epitopes clearly predominated. These results document a high degree of individuality for the cellular antitumor response and support the need for individualizing the monitoring and therapeutic approaches to the primary targets of the autologous T cell response, which may finally lead to a more effective cancer immunotherapy.