bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Al and Y incorporation on the structure of HfO2
Authors: Wang X. F. , Li Quan , Moreno M. S.
Published: November 2008

We have investigated the structural changes in HfO2 thin films upon Y and Al incorporation. The crystallinity of the films is examined by transmission electron diffraction. The local coordination symmetries of the Hf atoms in the films are revealed by the profile of the oxygen K-edge measured in the electron energy loss spectroscopy (EELS). The EEL spectra are then simulated using real-space multiple-scattering method. We found a good agreement between the simulated and the experimental EELS result of the pure HfO2. The Y incorporation indeed stabilized HfO2 to a cubic structure. Nevertheless, it also contributed to possible lattice distortion and/or creation of complex defect states other than O vacancies, causing discrepancies between the experimental and the simulated results. As a comparison, the local symmetry of Hf is largely degraded upon the incorporation of Al, which not only amorphorized HfO2, but also introduced significantly amount of O vacancies in the film.
Ion-ion correlation attraction in a molecular solvent
Authors: Pegado Luís , Jönsson Bo , Wennerström Håkan
Published: November 2008

We have performed Monte Carlo simulations for two like-charged infinite plates with counterions and solvent in between. The solvent is described at the primitive model (PM) level and also as a Stockmayer fluid. Both descriptions share the same qualitative ion correlation picture. At sufficiently high coupling, the pressure between the plates shows an attractive minimum, which is lost or reduced upon decreasing counterion valency, surface charge density, or increasing the screening. The pressure profiles become more oscillatory with higher density, which masks the ion-ion correlation attraction. An interpretation in terms of interaction free energies rather than pressures clarifies the picture. Analyzing the different contributions to the pressure gives further support to the conclusions; the same components are responsible for the same effect in the PM and in the molecular solvent.
Neutral evolution of proteins: The superfunnel in sequence space and its relation to mutational robustness
Authors: Noirel Josselin , Simonson Thomas
Published: November 2008

Following Kimura’s neutral theory of molecular evolution [M. Kimura, The Neutral Theory of Molecular Evolution (Cambridge University Press, Cambridge, 1983) (reprinted in 1986)], it has become common to assume that the vast majority of viable mutations of a gene confer little or no functional advantage. Yet, in silico models of protein evolution have shown that mutational robustness of sequences could be selected for, even in the context of neutral evolution. The evolution of a biological population can be seen as a diffusion on the network of viable sequences. This network is called a “neutral network.” Depending on the mutation rate μ and the population size N, the biological population can evolve purely randomly (μN⪡1) or it can evolve in such a way as to select for sequences of higher mutational robustness (μN⪢1). The stringency of the selection depends not only on the product μN but also on the exact topology of the neutral network, the special arrangement of which was named “superfunnel.” Even though the relation between mutation rate, population size, and selection was thoroughly investigated, a study of the salient topological features of the superfunnel that could affect the strength of the selection was wanting. This question is addressed in this study. We use two different models of proteins: on lattice and off lattice. We compare neutral networks computed using these models to random networks. From this, we identify two important factors of the topology that determine the stringency of the selection for mutationally robust sequences. First, the presence of highly connected nodes (“hubs”) in the network increases the selection for mutationally robust sequences. Second, the stringency of the selection increases when the correlation between a sequence’s mutational robustness and its neighbors’ increases. The latter finding relates a global characteristic of the neutral network to a local one, which is attainable through experiments or molecular modeling.
Improvement and protection of niobium surface superconductivity by atomic layer deposition and heat treatment
Authors: Proslier T. , Zasadzinski J. , Moore J. , Pellin M. , Elam J. , Cooley L. , Antoine C. , Norem J. , Gray K. E.
Published: November 2008

A method to treat the surface of Nb is described, which potentially can improve the performance of superconducting rf cavities. We present tunneling and x-ray photoemission spectroscopy measurements at the surface of cavity-grade niobium samples coated with a 3 nm alumina overlayer deposited by atomic layer deposition. The coated samples baked in ultrahigh vacuum at low temperature degraded superconducting surface. However, at temperatures above 450 C, the tunneling conductance curves show significant improvements in the superconducting density of states compared with untreated surfaces.
Near-field scanning optical microscopy to study nanometric structural details of LiNbO3 Zn-diffused channel waveguides
Authors: Canet-Ferrer J. , Martinez-Pastor J. , Cantelar E. , Jaque F. , Lamela J. , Cussó F. , Lifante G.
Published: November 2008

A near-field scanning optical microscope (NSOM) is used to perform structural and optical characterization of the surface layer after Zn diffusion in a channel waveguide fabricated on lithium niobate. A theoretical approach has been developed in order to extract refractive index contrast from NSOM optical transmission measurements (illumination configuration). As a result, different solid phases present on the sample surface can be identified, such as ZnO and ZnNb2O6. They appear like submicrometric crystallites aligned along the domain wall direction, whose origin can be ascribed to some strain relaxation mechanism during the annealing process after Zn diffusion.
Modeling dilute sediment suspension using large-eddy simulation with a dynamic mixed model
Authors: Chou Yi-Ju , Fringer Oliver B.
Published: November 2008

Transport of suspended sediment in high Reynolds number channel flows [Re=O(600 000)] is simulated using large-eddy simulation along with a dynamic-mixed model (DMM). Because the modeled sediment concentration is low and the bulk Stokes’ number (Stb) is small during the simulation, the sediment concentration is calculated through the use of the Eulerian approach. In order to employ the DMM for the suspended sediment, we formulate a generalized bottom boundary condition in a finite-volume formulation that accounts for sediment flux from the bed without requiring specific details of the underlying turbulence model. This enables the use of the pickup function without requiring any assumptions about the behavior of the eddy viscosity. Using our new boundary condition, simulations indicate that the resolved component of the vertical flux is one order of magnitude greater than the resolved subfilter-scale flux, which is in turn one order of magnitude greater than the eddy-diffusive flux. Analysis of the behavior of the suspended sediment above the bed indicates the existence of three basic time scales that arise due to varying degrees of competition between the upward turbulent flux and downward settling flux. Instantaneous sediment concentration and velocity fields indicate that streamwise vortices account for a bulk of the resolved flux of sediment from the bed.
Low-energy exciton states in a ZnO cylindrical nanodisk
Authors: Xiong Wen , Li Shu-Shen
Published: November 2008

We consider the electron-hole pair confined in a simplified infinite potential. The low-lying excition states in a ZnO cylindrical nanodisk are calculated based on effective-mass theory. To further understand the optical properties, we calculate the linear optical susceptibilities χ(w) and the radiative recombination lifetime τ of excitons in a ZnO nanodisk. The exciton radiative lifetime in a cylindrical nanodisk is of the order of tens of picoseconds, which is small compared with the lifetime of bulk ZnO material.
Interaction potentials, spectroscopy, and transport properties of Ne+–He and He+–Ne
Authors: Wright Timothy G. , Gray Benjamin R. , Viehland Larry A. , Johnsen Rainer
Published: November 2008

High-level ab initio potential energy curves are calculated for the lowest few states of the [He–Ne]+ complex. RCCSD(T) calculations are employed with large basis sets (up to sextuple-ζ), including extrapolation to the basis set limit, taking account of spin-orbit coupling. In addition, core-valence correlation and multireference effects are investigated. We calculate spectroscopic parameters and compare these to experimentally determined values, to other high-level ab initio results, and to results from potentials that are fitted to experimental data. We present the results of new measurements of the mobility of Ne+ in He. We also calculate mobilities for Ne+ in He, and He+ in Ne, from our potentials and from recent fitted potentials; and compare the calculated and experimental mobilities graphically and statistically.
A linear-scaling spectral-element method for computing electrostatic potentials
Authors: Watson Mark A. , Hirao Kimihiko
Published: November 2008

A new linear-scaling method is presented for the fast numerical evaluation of the electronic Coulomb potential. Our approach uses a simple real-space partitioning of the system into cubic cells and a spectral-element representation of the density in a tensorial basis of high-order Chebyshev polynomials. Electrostatic interactions between non-neighboring cells are described using the fast multipole method. The remaining near-field interactions are computed in the tensorial basis as a sum of differential contributions by exploiting the numerical low-rank separability of the Coulomb operator. The method is applicable to arbitrary charge densities, avoids the Poisson equation, and does not involve the solution of any systems of linear equations. Above all, an adaptive resolution of the Chebyshev basis in each cell facilitates the accurate and efficient treatment of molecular systems. We demonstrate the performance of our implementation for quantum chemistry with benchmark calculations on the noble gas atoms, long-chain alkanes, and diamond fragments. We conclude that the spectral-element method can be a competitive tool for the accurate computation of electrostatic potentials in large-scale molecular systems.
Optimized auxiliary basis sets for explicitly correlated methods
Authors: Yousaf Kazim E. , Peterson Kirk A.
Published: November 2008

Auxiliary basis sets for use in explicitly correlated MP2-F12 and CCSD-F12 methods, in which three- and four-electron integrals are approximated as products of two-electron integrals through the resolution of the identity (RI), have been optimized for the elements H, B–Ne, and Al–Ar. Fully matched to the recently constructed cc-pVnZ-F12 orbital basis sets, these new auxiliary basis sets result in very small RI errors, as exemplified by the calculated atomization energies of 42 molecules at the MP2-F12 level. Their utility in calculating smooth potential energy surfaces is also demonstrated in calculations of the spectroscopic properties of several diatomic molecules.
Enhanced electric field tunable dielectric properties of Ba(Sn0.15Ti0.85)O3 thin films
Authors: Song S. N. , Zhai J. W. , Gao L. N. , Yao X. , Hung T. F. , Xu Z. K.
Published: November 2008

Highly (100)-oriented barium stannate titanate Ba(Sn0.15Ti0.85)O3 (BTS) thin films were deposited on SrTiO3 (STO) and Nb doped SrTiO3 (NSTO) single-crystal substrates through sol-gel process, respectively. Coplanar capacitance and parallel plate capacitance structure configurations were formed by preparing interdigital electrodes (IDEs) and parallel plate electrodes (PPEs) on BTS thin film. The tunability of films with IDE was 45.54%, while the tunability of films with PPE was only 11.54% at the frequency of 1 MHz with an applied electric field of 80 kV/cm. This result showed that the tunability in the a-b plane contributes markedly to the measurements obtained with the IDE.
The structure and morphology of (112)-oriented Cu(In,Ga)Se2 epitaxial films
Authors: Liao Dongxiang , Rockett Angus
Published: November 2008

The properties of the {112} surfaces of Cu(In,Ga)Se2 (CIGS) are important to the performance of photovoltaic devices based on these materials. Epitaxial CIGS films were grown on GaAs (111)A (cation-terminated) and B (anion-terminated) substrates and the structure and morphology of the films were studied. There are a large number of rotational twins in films grown on (111)B substrates, but not for (111)A substrates. The ﬁlm surfaces consist of shallow triangular pyramids bounded by one type of ⟨110⟩ step. The steps show both sharp inside and outside corners. New layers nucleated as islands at step edges. The step heights are a mixture of single and multiple atomic layers. The change in surface chemistry from cation to anion terminated affects the measured electronic states comprising the valence band and is probably accompanied by a shift in the valence band edge. There is a distinct difference in step edge shape that shows a difference in step kink density but the expected high kink energy on both surfaces indicates that this may be due to kinetic rather than thermodynamic effects.
Giant magnetoresistance as a probe of magnetostatic coupling in NiFe/Au/Co/Au multilayers
Authors: Urbaniak M.
Published: November 2008

Magnetic hysteresis of [NiFe/Au/Co/Au]N multilayers displaying giant magnetoresistance was analyzed by using micromagnetic simulation. It was found that magnetostatic fields of stripe domains in Co layers, with a perpendicular magnetic anisotropy, lead to a replication of those domains in a magnetic configuration of NiFe layers possessing an in-plane shape anisotropy. It was shown that a local minimum of resistance versus an external magnetic field is a signature of the domain replication in systems with alternating perpendicular and the in-plane anisotropies.
All-optical diode action with quasiperiodic photonic crystals
Authors: Biancalana Fabio
Published: November 2008

We theoretically investigate the possibility of realizing a nonlinear all-optical diode by using the unique features of quasiperiodic one-dimensional photonic crystals. The interplay between the intrinsic spatial asymmetry in odd-order Thue–Morse lattices and Kerr nonlinearity, combined with the unconventional field localization properties of this class of quasiperiodic sequences, gives rise to sharp resonances that can be used to give a polarization-insensitive nonreciprocal propagation with a contrast close to unity for low optical intensities.
Morphological evolution of SiGe films covered with and without native oxide during vacuum thermal annealing
Authors: Zhang Yong , Liao Linghong , LI Cheng , Lai Hongkai , Chen Songyan , Kang J. Y.
Published: November 2008

The morphological evolution of SiGe films was investigated during vacuum thermal annealing. We found that Ge islands preferentially form in the process of decomposition of native oxide covering the SiGe layer, while pits form as an effective means of relaxing strain in the SiGe layer passivated with hydrogen during vacuum thermal annealing. The formation of small size Ge islands weakly depends on the strain relaxation of the SiGe layer. The size of Ge islands increases with Ge content in the initial SiGe layer and the maximum density of Ge islands is obtained for the SiGe layer with a lower Ge content of 0.06 among the investigated samples. A mechanism to form Ge islands on SiGe films rather than strain driven is proposed in terms of surface potential energy profile induced by the process of decomposition of native oxide.
Comparison of Alq3/alkali-metal fluoride/Al cathodes for organic electroluminescent devices
Authors: Helander M. G. , Wang Z. B. , Mordoukhovski L. , Lu Z. H.
Published: November 2008

The tris-(8-hydroxy-quinolinato) aluminum (Alq3)∕LiF∕Al cathode is one of the most studied interfaces in organic electronics. Charge injection properties of the other alkali-metal fluorides (i.e., NaF, KF, RbF and CsF) at the Alq3/electron injection layer/Al cathode interface of organic light emitting diodes were studied. It is found, in contrast to most literature, that the alkali-metal fluorides all yield equivalent device performance, despite the significant difference in the physiochemical properties of these metal fluorides. The observed phenomena are explained by the comparable strong intrinsic molecular dipole moment of these fluorides, which result in strong interfacial dipoles at the Alq3∕Al interface. This is consistent with ultraviolet photoelectron spectroscopy results and recent theory in literature. Difference in thickness dependence was also observed. LiF is found to be unique amongst the alkali-metal fluorides in terms of the thickness dependence of the device performance. This trend is found to strongly correlate with the growth mode of the metal fluoride on the Alq3 surface; LiF quickly transitions to layer-by-layer growth after the initial island nucleation, while the other alkali-metal fluorides tend to grow as clustered islands on top of a surface wetting layer.
Modeling of an advanced concept of a double stage Hall effect thruster
Authors: Garrigues L. , Boniface C. , Hagelaar G. J. M. , Boeuf J. P.
Published: November 2008

We present a study of the principle and operation of a two-stage Hall effect thruster, the SPT-MAG, using a two-dimensional quasineutral hybrid model coupled with a Monte Carlo simulation of electron transport. The purpose of the two-stage design is the separation of ion production and acceleration in two separate chambers, the ionization stage and the acceleration stage, with separate control of acceleration voltage and total ionization. The originality of the SPT-MAG lies in the magnetic field configuration in the ionization chamber. Electrons are confined by this magnetic field while ions are supposed to be trapped in the electric potential well supposedly resulting from the magnetic configuration, and guided toward the acceleration stage. The acceleration stage is similar to the channel of a conventional Hall effect thruster. The purpose of this paper is to clarify the physics of the SPT-MAG and to understand the formation of the positive ion trap in the ionization chamber. Using a hybrid model and a Monte Carlo simulation we show that under typical operating conditions most of the ionization in the chamber is due to high energy electrons accelerated in the channel and entering the chamber rather than to electrons accelerated by the voltage applied in the ionization chamber. We also raise the question of the possible role of an additional emissive cathode inside the ionization chamber. The model predicts that an electric potential well guiding the ions to the channel entrance forms in the chamber only if the intermediate electrode inside the chamber is an emissive cathode (which is not the case in recent configurations used for this thruster).
Analytical solutions to the Navier–Stokes equations
Authors: Manwai Yuen
Published: November 2008

With the previous results for the analytical blowup solutions of the N-dimensional (N≥2) Euler–Poisson equations, we extend the same structure to construct an analytical family of solutions for the isothermal Navier–Stokes equations and pressureless Navier–Stokes equations with density-dependent viscosity.
Development of a portable therapeutic and high intensity ultrasound system for military, medical, and research use
Authors: Lewis George K. , Olbricht William L.
Published: November 2008

We have developed a portable high power ultrasound system with a very low output impedance amplifier circuit (less than 0.3 Ω) that can transfer more than 90% of the energy from a battery supply to the ultrasound transducer. The system can deliver therapeutic acoustical energy waves at lower voltages than those in conventional ultrasound systems because energy losses owing to a mismatched impedance are eliminated. The system can produce acoustic power outputs over the therapeutic range (greater then 50 W) from a PZT-4, 1.54 MHz, and 0.75 in diameter piezoelectric ceramic. It is lightweight, portable, and powered by a rechargeable battery. The portable therapeutic ultrasound unit has the potential to replace “plug-in” medical systems and rf amplifiers used in research. The system is capable of field service on its internal battery, making it especially useful for military, ambulatory, and remote medical applications.
A capacitive probe with shaped probe bias for ion flux measurements in depositing plasmas
Authors: Petcu M. C. , Bronneberg A. C. , Sarkar A. , Blauw M. A. , Creatore M. , van de Sanden M. C. M.
Published: November 2008

The application of a pulse shaped biasing method implemented to a capacitive probe is described. This approach delivers an accurate and simple way to determine ion fluxes in diverse plasma mixtures. To prove the reliability of the method, the ion probe was used in a different configuration, namely, a planar Langmuir probe. In this configuration, the ion current was directly determined from the I-V characteristic and compared with the ion current measured with the pulse shaped ion probe. The results from both measurements are in excellent agreement. It is demonstrated that the capacitive probe is able to perform spatially resolved ion flux measurements under high deposition rate conditions (2–20 nm/s) in a remote expanding thermal plasma in Ar/NH3/SiH4 mixture.
Drop-on-demand printing of conductive ink by electrostatic field induced inkjet head
Authors: Choi Jaeyong , Kim Yong-Jae , Lee Sukhan , Son Sang Uk , Ko Han Seo , Nguyen Vu Dat , Byun Doyoung
Published: November 2008

Recently, inkjet printing technology has become crucial in many industrial fabrication fields mainly due to its advantages of noncontact and fast pattern generation. In this paper, we investigate an electrostatic field induced inkjet printing system, which is based on an electrohydrodynamic process, for drop-on-demand jetting. In order to locate the optimal jetting conditions, we tested jetting performance for various bias voltages and pulse signals. To investigate the characteristics of drop-on-demand operation and micropatterning, we used conductive silver ink and examined the drops and lines patterned on a substrate.
In situ heat treatment of ultrathin MgO layer for giant magnetoresistance ratio with low resistance area product in CoFeB/MgO/CoFeB magnetic tunnel junctions
Authors: Isogami Shinji , Tsunoda Masakiyo , Komagaki Kojiro , Sunaga Kazuyuki , Uehara Yuji , Sato Masashige , Miyajima Toyoo , Takahashi Migaku
Published: November 2008

In order to promote the grain growth of ultrathin MgO barrier deposited on a CoFeB layer, in situ infrared (IR) heat treatment just after the deposition of MgO barrier was examined. In case that IR heat treatment was not applied, tunneling magnetoresistance (TMR) ratio of CoFeB/MgO/CoFeB magnetic tunnel junction (MTJ) was significantly decreased with decreasing resistance area (RA) product to less than 10 Ω μm2. On the other hand, TMR ratio of 206% was achieved at the RA product of 2.1 Ω μm2 when the IR heat treatment was applied. According to the cross sectional transmission electron microscope images for the samples with 0.76-nm-thick (∼4 ML) MgO barrier, the (001) oriented well crystallized structure with smooth interface was observed for the IR heated sample. Moreover, it revealed that the lateral grain size of MgO was significantly enlarged compared to that for the sample without IR heating. The improvement of TMR properties at low RA product region by the heat treatment might be due to the decrease in grain boundaries of MgO layer where the coherent tunneling of Δ1 electrons is not restricted.
Near-field thermal imaging of nanostructured surfaces
Authors: Kittel A. , Wischnath U. F. , Welker J. , Huth O. , Rüting F. , Biehs S.-A.
Published: November 2008

We show that a near-field scanning thermal microscope, which essentially detects the local density of states of the thermally excited electromagnetic modes at nanometer distances from some material, can be employed for nanoscale imaging of structures on that material’s surface. This finding is explained theoretically by an approach which treats the surface structure perturbatively.
Displacement detection of silicon nanowires by polarization-enhanced fiber-optic interferometry
Authors: Nichol John M. , Hemesath Eric R. , Lauhon Lincoln J. , Budakian Raffi
Published: November 2008

We describe the displacement detection of freestanding silicon [111] nanowires by fiber-optic interferometry. We observe approximately a 50-fold enhancement in the scattered intensity for nanowires 40–60nm in diameter for incident light polarized parallel to the nanowire axis, as compared to perpendicular polarization. This enhancement enables us to achieve a displacement sensitivity of 0.5pm∕Hz for 15μW of light incident on the nanowire. The nanowires exhibit ultralow mechanical dissipation in the range of (2×10−15)–(2×10−14)kg∕s and could be used as mechanical sensors for ultrasensitive scanning probe force measurements.
Ultrastable in reflection photonic crystal fiber modal interferometer for accurate refractive index sensing
Authors: Jha Rajan , Villatoro Joel , Badenes Gonçal
Published: November 2008

A compact in reflection modal interferometer consisting of a stub of large-mode area photonic crystal fiber (PCF) spliced to standard fiber is presented. In the splice, the voids of the PCF are fully collapsed allowing so coupling and recombining PCF core and cladding modes. The interferometer is highly stable over time and can be used for different applications. The measuring of refractive index in the 1.33–1.45 range with high sensitivity is demonstrated. Sensing applications based on refractive index changes are also feasible.
Mirror-embedded microchannel for three-dimensional measurement of particle position
Authors: Choi Sungyoung , Park Je-Kyun
Published: November 2008

To enable easy implementation of three-dimensional (3D) characterization of flowing objects, we have developed a mirror-embedded microchannel to obtain 3D positional information from two different orthogonal-axis images. A silicon mirror reflects the side view of the channel and enables simultaneous imaging of the top and side views of the channel with a single lens. The measurement principle was verified by observing fluorescent streams simultaneously in both horizontal and vertical directions of a microchannel and measuring 3D positions of 6 and 10-μm sized beads without any optical modification of a microscope and additional optical equipment.
A catabolic block does not sufficiently explain how 2-deoxy-d-glucose inhibits cell growth
Authors: Ralser Markus , Wamelink Mirjam M. , Struys Eduard A. , Joppich Christian , Krobitsch Sylvia , Jakobs Cornelis , Lehrach Hans
Published: November 2008

The glucose analogue 2-deoxy-d-glucose (2-DG) restrains growth of normal and malignant cells, prolongs the lifespan ofC. elegans, and is widely used as a glycolytic inhibitor to study metabolic activity with regard to cancer, neurodegeneration, calorie restriction, and aging. Here, we report that separating glycolysis and the pentose phosphate pathway highly increases cellular tolerance to 2-DG. This finding indicates that 2-DG does not block cell growth solely by preventing glucose catabolism. In addition, 2-DG provoked similar concentration changes of sugar-phosphate intermediates in wild-type and 2-DG-resistant yeast strains and in human primary fibroblasts. Finally, a genome-wide analysis revealed 19 2-DG-resistant yeast knockouts of genes implicated in carbohydrate metabolism and mitochondrial homeostasis, as well as ribosome biogenesis, mRNA decay, transcriptional regulation, and cell cycle. Thus, processes beyond the metabolic block are essential for the biological properties of 2-DG.
On the biogeography of salt limitation: A study of ant communities
Authors: Kaspari Michael , Yanoviak Stephen P. , Dudley Robert
Published: November 2008

Sodium is an essential nutrient whose deposition in rainfall decreases with distance inland. The herbivores and microbial decomposers that feed on sodium-poor vegetation should be particularly constrained along gradients of decreasing sodium. We studied the use of sucrose and NaCl baits in 17 New World ant communities located 4–2757 km inland. Sodium use was higher in genera and subfamilies characterized as omnivores/herbivores compared with those classified as carnivores and was lower in communities embedded in forest litter than in those embedded in abundant vegetation. Sodium use was increased in ant communities further inland, as was preference for the baits with the highest sodium concentration. Sucrose use, a measure of ant activity, peaked in communities 10–100 km inland. We suggest that the geography of ant activity is shaped by sodium toxicity near the shore and by sodium deficit farther inland. Given the importance of ants in terrestrial ecosystems, changing patterns of rainfall with global change may ramify through inland food webs.
On the language of the Clinton-Dole presidential campaign debates
Authors: Halmari Helena
Published: November 2008

This article investigates the rhetorical strategies deployed by President Clinton and Senator Dole during the 1996 presidential debates. Clinton resorted to implicit persuasion and audience-oriented rhetorical strategies, while Doles persuasion was more explicit, and he did not avoid the use of dispreferred strategies such as opening his answers with the discourse particlewell. There were differences in the candidates use of personal pronouns: Dole usedI, you, andtheymore, whereas Clinton employed the audience-inclusiveweheavily. Clintons syntax and the content of his turns were coherently organized; Doles syntax showed occasional incoherence. The article does not claim that the use of successful rhetorical strategies is a necessary requirement for electoral success; it does, however, claim that a good orator is more likely to succeed.
The /‑(e)se/ in popular Dominican Spanish
Authors: Núñez-Cedeño Rafael
Published: November 2008

In Dominican Spanish, speakers produce the marker /‑(e)se/ to turn singulars arroz and gallina into the plurals arrócese and gallínase. Núñez Cedeño (2003) proposed that grammar alone is insufficient to account for its distribution. He introduced an information structure explanation suggesting that pragmatic factors guided speakers in selecting specific grammatical contexts to insert a /‑(e)se/ plural [instead of a /‑(e)s/ plural]. Colina (2006) proposed an alternative optimality analysis arguing that the regular plural is formed on a plural /‑s/ regulated by a constraint which prevents it from surfacing. This paper proposes a three-pronged approach to counter previous analyses. Firstly, it shows that the ‘double plural’ does not exist and that /‑e/, not /‑s/, signals plural formation. Secondly, this analysis shows that previous accounts relying on focused constituents only cannot hold because /‑se/ realization occurs both in focus and topic positions. Thirdly, based on the Expressive Morphology hypothesis, this article proposes that /‑se/ is an expressive morphological marker used under some restricted morpho-phonological conditions.
Ambiguity translated for children
Authors: Alvstad Cecilia
Published: November 2008

This article addresses ambiguity in translations for children. ‘Ambiguity’, here understood as something that allows for more than one interpretation, is supposed to be critical in translation for children as it clashes with some mediators’ ideas of what children’s literature is or ought to be. Hans Christian Andersen’s tale of “Den standhaftige Tinsoldat” [‘The steadfast tin soldier’] and a sample of twenty-four translations thereof (twelve into Swedish and twelve into Spanish) are used to explore different ways that ambiguity is translated for children. The objective is to determine if and how the tale’s ambiguities are manipulated in the various translations, and thus to initiate a theoretical discussion of ambiguity in translation for children. A difference is established between ‘textually resolvable’ and ‘textually irresolvable’ ambiguities and these two kinds of ambiguity are found to be treated differently in the analyzed sample of translations.
Translating social science
Authors: Price Joshua M.
Published: November 2008

Dedicated to the memory of Daniel Simeoni

Insufficient attention has been paid in Translation Studies to the challenges particular to translating social scientific texts. Of the few who have taken up the topic, Immanuel Wallerstein has argued that one of the distinguishing characteristics of social scientific texts is that they traffic in concepts. Wallerstein wants the translation of social science to further the possibility of a universal conversation in the social sciences. I argue that a universal conversation in the social sciences is neither possible nor desirable. Instead, this article proposes that translating social science can contribute to conceptual clarification and elaboration. In this way, the translation may complement and further the flowering of the ‘original’ concept. The essay concludes with an extended example—how ‘bewilderment’ might be translated into Spanish.
The Meta-inductivist's Winning Strategy in the Prediction Game: A New Approach to Hume's Problem
Authors: Schurz Gerhard
Published: November 2008

This article suggests a ‘best alternative’ justification of induction (in the sense of Reichenbach) which is based onmeta-induction. The meta-inductivist applies the principle of induction to all competing prediction methods which areaccessibleto her. It is demonstrated, and illustrated by computer simulations, that there exist meta-inductivistic prediction strategies whose success is approximately optimal among all accessible prediction methods in arbitrary possible worlds, and which dominate the success of every noninductive prediction strategy. The proposed justification of meta-induction is mathematically analytical. It implies, however, an a posteriori justification of object-induction based on the experiences in our world.
Resurrecting Biological Essentialism
Authors: Devitt Michael
Published: November 2008

The article defends the doctrine that Linnaean taxa, including species, have essences that are, at least partly, underlying intrinsic, mostly genetic, properties. The consensus among philosophers of biology is that such essentialism is deeply wrong, indeed incompatible with Darwinism. I argue that biological generalizations about the morphology, physiology, and behavior of species require structural explanations that must advert to these essential properties. The objection that, according to current “species concepts,” species are relational is rejected. These concepts are primarily concerned with what it is for a kind to be a species and throw little light on the essentialist issue of what it is for an organism to be a member of a particular kind. Finally, the article argues that this essentialism can accommodate features of Darwinism associated with variation and change.
N‐Acetylcysteine an Allium Plant Compound Improves High‐Sucrose Diet‐Induced Obesity and Related Effects
Authors: Souza Gisele A. , Ebaid Geovana X. , Seiva Fábio R. F. , Rocha Katiucha H. R. , Galhardi Cristiano Machado , Mani Fernanda , Novelli Ethel L. B.
Published: November 2008

This study was designed to determine whether N‐acetylcysteine (NAC, C5H9–NO3S), a compound from Allium species may be used as a complementary therapeutic agent, to inhibit high‐sucrose induced‐obesity and its effects on glucose tolerance, in vivo low‐density lipoprotein (LDL)‐oxidation and serum oxidative stress in rats. Initially, 24 male Wistar rats were divided into two groups: controls receiving standard chow (C, n = 6) and those receiving high‐sucrose diet (HS, n = 18). After 22 days, (HS) group was divided into three groups (n = 6/group); (HS‐HS) continued to eat high‐sucrose diet and water; (HS‐N) continued to eat high‐sucrose diet and received 2 mg l−1‐NAC in its drinking water; (HS‐CN) changing high‐sucrose to standard chow and receiving 2 mg l­1‐NAC in its drinking water. After 22 days of the HS‐group division (44 days of experimental period) body weight, body mass index and surface area were enhanced in HS‐HS rats (P < .001). HS‐HS rats had glucose intolerance, increased serum triacylglycerol (TG), very low‐density lipoprotein (VLDL), oxidized‐LDL (ox‐LDL) and lipid‐hydroperoxide (LH) than the others (P < .01). NAC in HS‐N and HS‐CN rats reduced the obesity markers, feed efficiency, LH and ox‐LDL, as well normalized glucose response, TG and VLDL (P < .01) in these groups compared with HS‐HS. Total antioxidant substances, GSH/GSSG ratio and glutathione‐reductase, were higher in HS‐N than in HS‐HS (P < .01). In conclusion, NAC improved high‐sucrose diet‐induced obesity and its effects on glucose tolerance, lipid profile, in vivo LDL‐oxidation and serum oxidative stress, enhancing antioxidant defences. The application of this agent may be feasible and beneficial for high‐sucrose diet‐induced obesity, which certainly would bring new insights on obesity‐related adverse effects control.
Technological and Nutritional Properties of Flours and Tortillas from Nixtamalized and Extruded Quality Protein Maize (Zea mays L.)
Authors: Gutiérrez‐Dorado R. , Ayala‐Rodríguez A. E. , Milán‐Carrillo J. , López‐Cervantes J. , Garzón‐Tiznado J. A. , López‐Valenzuela J. A. , Paredes‐López O. , Reyes‐Moreno C.
Published: November 2008

Nixtamalized and extruded flours from quality protein maize (QPM, V‐537C) and tortillas made from them were evaluated for some technological and nutritional properties and compared with the commercial brand MASECA. Both QPM flours showed higher (P < 0.05) protein content, total color difference, pH, available lysine, and lower (P < 0.05) total starch content, Hunter L value, water absorption index, gelatinization enthalpy, resistant starch, and retrograded resistant starch than nixtamalized MASECA flour. Tortillas from nixtamalized and extruded QPM flours had higher contents of essential amino acids than tortillas from MASECA flour, except for leucine. Tortillas from processed QPM flours also showed higher (P < 0.05) values of the nutritional indicators calculated protein efficiency ratio (C‐PER 1.80–1.85 vs. 1.04), apparent and true in vivo protein digestibility (78.4‐79.1 vs. 75.6% and 76.4–77.4 vs. 74.2%, respectively), PER (2.30–2.43 vs. 1.31), net protein retention (NPR; 2.88–2.89 vs. 2.11), and protein digestibility corrected amino acid score (PDCAAS; 54–55 vs. 29% based on preschool children and 100 vs. 85% based on adults) than MASECA flour. The use of QPM for flour and tortilla preparation may have a positive effect on the nutritional status of people from countries where these products are widely consumed.
An Inositolphosphorylceramide Synthase Is Involved in Regulation of Plant Programmed Cell Death Associated with Defense inArabidopsis
Authors: Wang Wenming , Yang Xiaohua , Tangchaiburana Samantha , Ndeh Roland , Markham Jennifer E. , Tsegaye Yoseph , Dunn Teresa M. , Wang Guo-Liang , Bellizzi Maria , Parsons James F. , Morrissey Danielle , Bravo Janis E. , Lynch Daniel V. , Xiao Shunyuan
Published: November 2008

The Arabidopsis thaliana resistance gene RPW8 triggers the hypersensitive response (HR) to restrict powdery mildew infection via the salicylic acid–dependent signaling pathway. To further understand how RPW8 signaling is regulated, we have conducted a genetic screen to identify mutations enhancing RPW8-mediated HR-like cell death (designated erh). Here, we report the isolation and characterization of the Arabidopsis  erh1 mutant, in which the At2g37940 locus is knocked out by a T-DNA insertion. Loss of function of ERH1 results in salicylic acid accumulation, enhanced transcription of RPW8 and RPW8-dependent spontaneous HR-like cell death in leaf tissues, and reduction in plant stature. Sequence analysis suggests that ERH1 may encode the long-sought Arabidopsis functional homolog of yeast and protozoan inositolphosphorylceramide synthase (IPCS), which converts ceramide to inositolphosphorylceramide. Indeed, ERH1 is able to rescue the yeast aur1 mutant, which lacks the IPCS, and the erh1 mutant plants display reduced (∼53% of wild type) levels of leaf IPCS activity, indicating that ERH1 encodes a plant IPCS. Consistent with its biochemical function, the erh1 mutation causes ceramide accumulation in plants expressing RPW8. These data reinforce the concept that sphingolipid metabolism (specifically, ceramide accumulation) plays an important role in modulating plant programmed cell death associated with defense.
Cellulose Binding Protein from the Parasitic Nematode Heterodera schachtii Interacts with Arabidopsis Pectin Methylesterase: Cooperative Cell Wall Modification during Parasitism
Authors: Hewezi Tarek , Howe Peter , Maier Tom R. , Hussey Richard S. , Mitchum Melissa Goellner , Davis Eric L. , Baum Thomas J.
Published: November 2008

Plant–parasitic cyst nematodes secrete a complex of cell wall–digesting enzymes, which aid in root penetration and migration. The soybean cyst nematode Heterodera glycines also produces a cellulose binding protein (Hg CBP) secretory protein. To determine the function of CBP, an orthologous cDNA clone (Hs CBP) was isolated from the sugar beet cyst nematode Heterodera schachtii, which is able to infect Arabidopsis thaliana. CBP is expressed only in the early phases of feeding cell formation and not during the migratory phase. Transgenic Arabidopsis expressing Hs CBP developed longer roots and exhibited enhanced susceptibility to H. schachtii. A yeast two-hybrid screen identified Arabidopsis pectin methylesterase protein 3 (PME3) as strongly and specifically interacting with Hs CBP. Transgenic plants overexpressing PME3 also produced longer roots and exhibited increased susceptibility to H. schachtii, while a pme3 knockout mutant showed opposite phenotypes. Moreover, CBP overexpression increases PME3 activity in planta. Localization studies support the mode of action of PME3 as a cell wall–modifying enzyme. Expression of CBP in the pme3 knockout mutant revealed that PME3 is required but not the sole mechanism for CBP overexpression phenotype. These data indicate that CBP directly interacts with PME3 thereby activating and potentially targeting this enzyme to aid cyst nematode parasitism.
Improved quality of life for romiplostim‐treated patients with chronic immune thrombocytopenic purpura: results from two randomized, placebo‐controlled trials
Authors: George James N. , Mathias Susan D. , Go Ronald S. , Guo Matthew , Henry David H. , Lyons Roger , Redner Robert L. , Rice Lawrence , Schipperus Martin R.
Published: November 2008

Health‐related quality of life (HRQoL) is a major concern for adults with chronic immune thrombocytopenic purpura (ITP) due to the symptoms associated with the disease and its treatment. This study utilized the ITP‐patient assessment questionnaire (ITP‐PAQ), a specialized HRQoL questionnaire for ITP, to investigate the humanistic burden of ITP and the impact of romiplostim therapy on HRQoL in two, placebo‐controlled, phase 3 clinical trials of splenectomized and non‐splenectomized patients. ITP‐PAQ was self‐administered to ITP patients at baseline, and weeks 4, 12 and 24 of treatment. Splenectomized patients had lower baseline HRQoL scores than non‐splenectomized patients in seven of 10 scales (P < 0·05). After 24 weeks of romiplostim therapy, splenectomized patients showed significant improvements over placebo in four of 10 ITP‐PAQ Scales (Symptoms, P = 0·0337; Bother, P = 0·0126; Social Activity, P = 0·0145; and Women’s Reproductive Health, P = 0·0184). Non‐splenectomized patients demonstrated significant improvement over placebo in the Activity Scale (P = 0·0458). Data pooled from the two trials, adjusted for splenectomy status, showed significant improvement for romiplostim‐treated patients in six scales; Symptoms, Bother, Activity, Fear, Social Activity and Women’s Reproductive Health. These results suggest that adult patients with chronic ITP have improved HRQoL following romiplostim therapy.
Carnivory and resource‐based niche differentiation in anuran larvae: implications for food web and experimental ecology
Authors: SCHIESARI LUIS , WERNER EARL E. , KLING GEORGE W.
Published: November 2008

1. Food webs represent the paths of material and energy flow through organisms in an ecosystem. Anuran larvae are important components of pond food webs: they are abundant, consume large quantities of food and serve as prey for many organisms. However, there are very basic uncertainties about the feeding ecology of anuran larvae; for instance, as to which trophic level they belong and whether species differ in resource use. Because anuran larvae have been employed in model systems in experimental ecology for decades, these uncertainties could lead to misinterpretation of published experiments, or inadequate designs of experiments directed at general, conceptual issues in ecology.

2. Using13C and15N stable isotope and gut content analyses of free‐ranging and enclosed tadpoles of four ranid species (Lithobates sylvaticus,L. pipiens,L. clamitans,L. catesbeianus) in the food webs of six wetlands, we tested the following null hypotheses: (i) that anuran larvae are strict primary consumers; (ii) that they are non‐selective feeders and therefore exhibit little feeding niche differentiation; (iii) that they are opportunistic consumers and (iv) that their diet remains unchanged through ontogeny.

3. All four species consumed and assimilated substantial amounts of animal food; bullfrog larvae, in particular, appear to be predatory. Significant feeding niche differentiation among species occurred with respect to the sources of carbon, consumption of animal matter and nutritional quality of food ingested. We further documented opportunistic feeding habits and ontogenetic shifts in diet.

4. Collectively, these studies revealed complex trophic relationships that might require a reconsideration of the role of anuran larvae in pond food webs, as well as a reinterpretation of results of previous studies employing anuran larvae in model experimental systems.