bluuebunny/crossref_metadata_2025 huggingface dataset:
Design and analysis of a high-power radial multi-way combiner
Authors: Jain Akhilesh , Gupta Alok K. , Sharma Deepak Kumar , Hannurkar Pundlik Rama , Pathak Surya Kant
Published: October 2013

In this paper, the design analysis of a multi-way and high-power radial combiner is presented. This combiner incorporates a rigid stripline-type combining structure. This analysis, based on an equivalent circuit model and segmentation of the radial transmission line, provides simple design formulae. The developed methodology, after fine-tuning with the help of an electromagnetic full-wave simulator, is physically demonstrated by developing a high-power (16 kW average) and high combining-efficiency (98.9%) 16-way combiner at the center frequency of 505.8 MHz. Its efficient and repeatable performance, fabrication-friendly structure, and absence of the heat-related problem, caused by the isolation resistor, are the main features of this design.
Satisfaction with Life Scale in a Representative Sample of Spanish Adults: Validation and Normative Data
Authors: Vázquez Carmelo , Duque Almudena , Hervás Gonzalo
Published: October 2013

The Satisfaction with Life Scale (SWLS) is a measure widely used to assess life satisfaction. This paper aims to test its psychometric properties, factor structure, and distribution scores across age, gender, education, and employment status. For this purpose, a representative sample of the Spanish population (N = 2,964) was used. Although analyses showed no significant differences across age or gender, participants with higher education level and those who held an occupation were more satisfied with their lives. Confirmatory factor analysis revealed a unifactorial structure with significant correlations between the SWLS, and subjective happiness and social support. The internal consistency of the scale was .88. Thus, our results indicate that the Spanish version of the SWLS is a valid and reliable measure of life satisfaction within the Spanish context.
Acute Cough Illness in General Practice – Predictive Value of Clinical Judgement and Accuracy of Requesting Chest X-Rays
Authors: Blaeuer Silvana Romerio , Bally Klaus , Tschudi Peter , Martina Benedict , Zeller Andreas
Published: October 2013

Ziel dieser Arbeit war, bei Patienten mit akutem Husten (<3 Wochen) die Qualität der hausärztlichen Beurteilung hinsichtlich Voraussage des Vorliegens oder Ausschluss einer Pneumonie zu messen und den Stellenwert des Thorax-Röntgenbildes im diagnostischen Prozess zu evaluieren. Die Hausärzte wurden gebeten, bei 212 konsekutiven Patienten aufgrund der Klinik (Anamnese und Status) ihren Verdacht auf das Vorliegen einer Pneumonie festzuhalten und den Grund für die Verordnung eines Thoraxbildes zu dokumentieren. Nach Anamnese und Status konnten Hausärzte akkurat beurteilen, bei welchen Patienten mit akutem Husten eine Pneumonie vorliegt (PPV 80% [95% CI 0,66–0,89]) oder nicht (NPV 100% [95% CI 0,97–1,0]) und bei welchen Patienten ein Thorax-Röntgenbild notwendig ist oder nicht (spearman's rho 0,54, p<0,0001).
Präoperative Hypertonie: Wie vorgehen – einige Praxistipps
Authors: Muggli Franco , Suter Paolo M.
Published: October 2013

Wenn immer möglich sollte ein normaler präoperativer Blutdruck angestrebt werden. Bei präoperativen Blutdruckwerten von >180 mmHg soll bei Wahloperationen die Operation verschoben werden (adäquate Blutdruckmessung vorausgesetzt, z. B. bei Bedarf mittels 24 h-ABPM). Bei Blutdruckwerten <180 mmHg soll wenn möglich – d. h. bei Wahloperationen idealerweise auch die letztgenannte Strategie verfolgt werden. Falls dies nicht möglich ist, ist das perioperative Risiko bei optimalem Anästhesiemanagement und fehlenden Komorbiditäten wahrscheinlich nicht erhöht. Die Problematik der prä- und perioperativen Hypertonie ist vorhanden, aber kontrollierbar, was aber nicht bedeutet, dass man dem perioperativen Blutdruck keine Aufmerksamkeit schenken soll. Entsprechend treffend schrieb ein Editorialist vor bald zehn Jahren «Preoperative hypertension: remain wary? Yes – cancel surgery? No».
Der kreative Prozess als Bewältigungs-Strategie
Authors: Vollmer Barbara
Published: October 2013

Kreative Prozesse können als Bewältigungs-Strategie gesehen werden. Sie bieten eine Plattform für die differenzierte Bearbeitung von Problemen. Grundlegende Bedürfnisse werden befriedigt: Während des Arbeitens werden Selbstwirksamkeits-Signale ausgeschüttet, durch die ästhetische Problembearbeitung wird die Bestimmtheit erhöht. Es kann eine affiliative Bedürfniserfüllung erwachsen. Die emotions-zentrierte Problembehandlung ermöglicht neue Lösungsfindungen. Widersprüche lassen sich durch den ästhetischen Vergleich zwischen Beobachtungen und Vorstellungen zu einem stimmigen Endergebnis verarbeiten, das stabilisiert und neue Perspektiven eröffnet. Dabei schwankende Bestimmtheits-Signale können Flow-Erleben erzeugen. Kennzeichnend ist die außerordentliche Überzeugungskraft, mit der die hier gewonnenen Erkenntnisse verfolgt werden.
Effects of Cerebral Ischemic and Reperfusion on T2∗-Weighted MRI Responses to Brief Oxygen Challenge
Authors: Shen Qiang , Du Fang , Huang Shiliang , Duong Timothy Q
Published: October 2013

This study characterized the effects of cerebral ischemia and reperfusion on T2∗-weighted magnetic resonance image (MRI) responses to brief oxygen challenge (OC) in transient (60 minutes) cerebral ischemia in rats. During occlusion, the ischemic core tissue showed no significant OC response, whereas the perfusion–diffusion mismatch tissue showed markedly higher percent changes relative to normal tissue. After reperfusion, much of the pixels with initial exaggerated OC responses showed normal OC responses, and the majority of these tissues were salvaged as defined by endpoint T2 MRI. The initial core pixels showed exaggerated OC responses after reperfusion, but the majority of the core pixels eventually became infarct, suggesting exaggerated OC responses do not necessarily reflect salvageable tissue. Twenty-four hours after stroke, basal T1 increased in the ischemic core. Oxygen challenge decreased T1 significantly in the core, indicative of the substantial increases in dissolved oxygen in the core as the result of hyperperfusion. We concluded that exaggerated T2∗-weighted MRI responses to OC offer useful insight in ischemic tissue fates. However, exaggerated OC pixels are not all salvageable, and they exhibited complex dynamics depending on reperfusion status, hyperperfusion, and edema effects.
Human sorCS1 binds sortilin and hampers its cellular functions
Authors: Larsen Jakob Vejby , Hermey Guido , Sørensen Esben Skipper , Prabakaran Thaneas , Christensen Erik Ilsø , Gliemann Jørgen , Madsen Peder , Petersen Claus Munck
Published: October 2013

Sortilin and sorCS1 [sortilin-related Vps10p (vacuolar protein sorting/targeting protein 10) domain-containing receptor 1], both members of the Vps10p-D (Vps10p-domain) receptor family, are synthesized as precursor proteins and are converted into their mature form by enzymatic cleavage of a short N-terminal propeptide. SorCS1 does not bind its propeptide, but sortilin is able to bind not just its own propeptide, but also that of sorCS1. In the present study we show that the propeptide region of sorCS1 contains two separate sites for binding to sortilin and that only one of these sites is removed from human (as opposed to mouse) sorCS1 during processing. This leaves mature human sorCS1 with a sortilin-binding N-terminus, which allows formation of a complex between the two receptors in solution and on cell membranes. Furthermore, we find that the interaction with sorCS1 has a pronounced effect on sortilin's ability to mediate the cellular uptake of alternative ligands, and to hamper its facilitation of CNTF (ciliary neutrophic factor) signalling and the induction of phosphorylated STAT3 (signal transducer and activator of transcription 3). Thus the present study reveals a novel regulatory mechanism and suggest an entirely new role for sorCS1 as a modulator of sortilin function.
Kinetic characterization of high-activity mutants of human butyrylcholinesterase for the cocaine metabolite norcocaine
Authors: Zhan Max , Hou Shurong , Zhan Chang-Guo , Zheng Fang
Published: October 2013

It has been known that cocaine produces its toxic and physiological effects through not only cocaine itself, but also norcocaine formed from cocaine oxidation catalysed by microsomal CYP (cytochrome P450) 3A4 in the human liver. The catalytic parameters (kcat and Km) of human BChE (butyrylcholinesterase) and its three mutants (i.e. A199S/S287G/A328W/Y332G, A199S/F227A/S287G/A328W/E441D and A199S/F227A/S287G/A328W/Y332G) for norcocaine have been characterized in the present study for the first time and compared with those for cocaine. On the basis of the obtained kinetic data, wild-type human BChE has a significantly lower catalytic activity for norcocaine (kcat=2.8 min−1, Km=15 μM and kcat/Km=1.87×105 M−1·min−1) compared with its catalytic activity for (−)-cocaine. The BChE mutants examined in the present study have considerably improved catalytic activities against both cocaine and norcocaine compared with the wild-type enzyme. Within the enzymes examined in the present study, the A199S/F227A/S287G/A328W/Y332G mutant (CocH3) is identified as the most efficient enzyme for hydrolysing both cocaine and norcocaine. CocH3 has a 1080-fold improved catalytic efficiency for norcocaine (kcat=2610 min−1, Km=13 μM and kcat/Km=2.01×108 M−1·min−1) and a 2020-fold improved catalytic efficiency for cocaine. It has been demonstrated that CocH3 as an exogenous enzyme can rapidly metabolize norcocaine, in addition to cocaine, in rats. Further kinetic modelling has suggested that CocH3 with an identical concentration with that of the endogenous BChE in human plasma can effectively eliminate both cocaine and norcocaine in a simplified kinetic model of cocaine abuse.
Analysis of the cytokine profile in the duodenal mucosa of refractory coeliac disease patients
Authors: Caruso Roberta , Marafini Irene , Sedda Silvia , Del Vecchio Blanco Giovanna , Giuffrida Paolo , MacDonald Thomas T. , Corazza Gino Roberto , Pallone Francesco , Di Sabatino Antonio , Monteleone Giovanni
Published: October 2013

RCD [refractory CD (coeliac disease)] is characterized by severe symptoms/signs of malabsorption and mucosal damage unresponsive to a GFD (gluten-free diet). The pathogenesis of RCD is not fully understood. In the present paper, we have characterized the mucosal profile of effector cytokines in RCD. Duodenal biopsies were taken from patients with RCD, patients with active CD and normal controls and were analysed for inflammatory cytokines by real-time PCR and ELISA. IFN (interferon)-γ and IL (interleukin)-21 transcripts were increased in active CD patients but not in RCD patients as compared with normal controls, whereas IL-17A RNA was up-regulated in both active CD and RCD. No significant increase in IL-15 transcripts was observed in both active CD and RCD, whereas IL-15 protein was increased in active CD. IL-6 and TNF (tumour necrosis factor)-α were up-regulated only in RCD. As a proof, we present the case of a woman affected by RCD who responded to anti-TNF-α treatment with improvement of malabsorptive symptoms/signs but no healing of mucosal lesions. The findings indicate that the profile of mucosal effector cytokines differs between RCD and active CD and suggest that TNF-α, IL-6 and IL-17A, but not Th1-type cytokines, could drive the detrimental response in this condition.
Nasal and Oral Inspiration During Natural Speech Breathing
Authors: Lester Rosemary A. , Hoit Jeannette D.
Published: October 2013

Purpose

The purpose of this study was to determine the typical pattern for inspiration during speech breathing in healthy adults, as well as the factors that might influence it.

Method

Ten healthy adults, 18–45 years of age, performed a variety of speaking tasks while nasal ram pressure, audio, and video recordings were obtained. Inspirations were categorized as nasal-only, oral-only, simultaneous nasal and oral, or alternating nasal and oral inspiration. The method was validated using nasal airflow, oral airflow, audio, and video recordings for 2 participants.

Results

The predominant pattern was simultaneous nasal and oral inspirations for all speaking tasks. This pattern was not affected either by the nature of the speaking task or by the phonetic context surrounding the inspiration. The validation procedure confirmed that nearly all inspirations during counting and paragraph reading were simultaneous nasal and oral inspirations, whereas for sentence reading, the predominant pattern was alternating nasal and oral inspirations across the 3 phonetic contexts.

Conclusions

Healthy adults inspire through both the nose and mouth during natural speech breathing. This pattern of inspiration is likely beneficial in reducing pathway resistance while preserving some of the benefits of nasal breathing.
Interpretation of Verb Phrase Telicity: Sensitivity to Verb Type and Determiner Type
Authors: Ogiela Diane A. , Schmitt Cristina , Casby Michael W.
Published: October 2013

Purpose

The authors examine how adults use linguistic information from verbs, direct objects, and particles to interpret an event description as encoding a logical endpoint to the event described (in which case, it is telic) or not (in which case, it is atelic). Current models of aspectual composition predict that quantity-sensitive verbs combined with quantized objects produce telic predicates. Behavioral results from previous experiments have not unequivocally confirmed this prediction. The study presents a more fine-grained analysis that examines the influence of partitive verbs, resultative particles, and different determiner types on listeners' evaluations of verb phrases as telic or atelic.

Method

Forty-eight English-speaking adults participated in a truth-value judgment task to determine whether they interpreted verb phrases with different types of verbs and direct objects as telic or atelic. Participants viewed short videos and responded to a
yes/no
question after each one.

Results

The presence of partitive quantity-sensitive verbs and the presence of a definite determiner versus a cardinal number in quantized direct objects had a differential impact on listeners' interpretations of sentences as telic.

Conclusion

The results indicate that actual behavioral interpretations of telicity are meaningfully influenced by the presence of partitive verbs, resultative particles, and different types of determiners.
Automated modular high energy evaluation system for experimental thyristor devices
Authors: Lacouture Shelby , Lawson Kevin , Bayne Stephen , Giesselmann Michael , Scozzie Charles J. , O’Brien Heather , Ogunniyi Aderinto A.
Published: October 2013

A high energy, modular, completely automated test bed with integrated data acquisition and characterization systems was successfully designed in order to perform both safe operating area as well as very high volume reliability testing on experimental silicon carbide Super Gate Turn Off (SGTO) thyristors. Although the system follows a modular design philosophy, with each functional block acting as a peripheral to a main control module and can be adapted to arbitrary power and pulse width levels, for the specific SGTO devices initially evaluated it was configured to have the device discharge variable current levels of up to 6 kA into a 0.5 Ω resistive load with a relatively square pulse fixed at 100 μs full width at half maximum delivering energy levels up to 1.8 kJ to the load.
Effect of ambient air on liquid jet impingement on a moving substrate
Authors: Moulson J. B. T. , Green S. I.
Published: October 2013

An experimental investigation into the effect of surrounding air pressure on liquid jet impingement on a moving substrate was performed. The study was carried out with Newtonian liquids impacting dry substrates. A variety of jet speeds, substrate speeds, and liquid viscosities were studied. It was observed that, as is the case for Newtonian droplet impact, the surrounding air pressure plays a crucial role in the splashing behaviour of jet impingement. There exists a threshold pressure below which splash does not occur. It is proposed that for certain impingement conditions lamella detachment from the substrate occurs due to aerodynamic forces acting on the leading edge of the lamella, which destabilizes the balance between surface tension and fluid pressure forces.
Dependence of advection-diffusion-reaction on flow coherent structures
Authors: Tang Wenbo , Luna Christopher
Published: October 2013

A study on an advection-diffusion-reaction system is presented. Variability of the reaction process in such a system triggered by a highly localized source is quantified. It is found, for geophysically motivated parameter regimes, that the difference in bulk concentration subject to realizations of different source locations is highly correlated with the local flow topology of the source. Such flow topologies can be highlighted by Lagrangian coherent structures. Reaction is relatively enhanced in regions of strong stretching, and relatively suppressed in regions where vortices are present. In any case, the presence of a divergence-free background flow helps speed up the reaction process, especially when the flow is time-dependent. Probability density of various quantities characterizing the reaction processes is also obtained. This reveals the inherent complexity of the reaction-diffusion process subject to nonlinear background stirring.
Correction of the spectral calibration of the Joint European Torus core light detecting and ranging Thomson scattering diagnostic using ray tracing
Authors: Hawke J. , Scannell R. , Maslov M. , Migozzi J. B. ,   JET-EFDA Contributors
Published: October 2013

This work isolated the cause of the observed discrepancy between the electron temperature (Te) measurements before and after the JET Core LIDAR Thomson Scattering (TS) diagnostic was upgraded. In the upgrade process, stray light filters positioned just before the detectors were removed from the system. Modelling showed that the shift imposed on the stray light filters transmission functions due to the variations in the incidence angles of the collected photons impacted plasma measurements. To correct for this identified source of error, correction factors were developed using ray tracing models for the calibration and operational states of the diagnostic. The application of these correction factors resulted in an increase in the observed Te, resulting in the partial if not complete removal of the observed discrepancy in the measured Te between the JET core LIDAR TS diagnostic, High Resolution Thomson Scattering, and the Electron Cyclotron Emission diagnostics.
Entropic chaoticity for the steady state of a current carrying system
Authors: Bonetto F. , Loss M.
Published: October 2013

The steady state for a system of N particles under the influence of an external field and a Gaussian thermostat and colliding with random “virtual” scatterers can be obtained explicitly in the limit of small fields. We show that the sequence of steady state distributions, as N varies, is a chaotic sequence in the sense that the k particle marginal, in the limit of large N, is the k-fold tensor product of the 1 particle marginal. We also show that the chaoticity properties hold in the stronger form of entropic chaoticity.
Quasi-bound states and Fano effect in T-shaped graphene nanoribbons
Authors: Xu J. G. , Wang L. , Weng M. Q.
Published: October 2013

We study the quasi-bound state and the transport properties in the T-shaped graphene nanoribbon consisting of a metallic armchair-edge ribbon connected to a zigzag-edge sidearm. We systematically study the condition under which there are quasi-bound states in the system for a wide range of the system size. It is found that when the width of the sidearm is about half of the width of the armchair graphene nanoribbon, there is a quasi-bound state trapped at the intersection of the T-shaped structure. The quasi-bound states are truly localized in the sidearm but have small continuum components in the armchair graphene nanoribbons. The quasi-bound states have strong effect on the transport between the armchair leads through the Fano effect, but do not affect the transport between the armchair lead and the sidearm.
AA stacking, tribological and electronic properties of double-layer graphene with krypton spacer
Authors: Popov Andrey M. , Lebedeva Irina V. , Knizhnik Andrey A. , Lozovik Yurii E. , Potapkin Boris V. , Poklonski Nikolai A. , Siahlo Andrei I. , Vyrko Sergey A.
Published: October 2013

Structural, energetic, and tribological characteristics of double-layer graphene with commensurate and incommensurate krypton spacers of nearly monolayer coverage are studied within the van der Waals-corrected density functional theory. It is shown that when the spacer is in the commensurate phase, the graphene layers have the AA stacking. For this phase, the barriers to relative in-plane translational and rotational motion and the shear mode frequency of the graphene layers are calculated. For the incommensurate phase, both of the barriers are found to be negligibly small. A considerable change of tunneling conductance between the graphene layers separated by the commensurate krypton spacer at their relative subangstrom displacement is revealed by the use of the Bardeen method. The possibility of nanoelectromechanical systems based on the studied tribological and electronic properties of the considered heterostructures is discussed.
Inlet conditions for wave packet models in turbulent jets based on eigenmode decomposition of large eddy simulation data
Authors: Rodríguez Daniel , Sinha Aniruddha , Brès Guillaume A. , Colonius Tim
Published: October 2013

This paper makes contributions towards reduced-order models of wave packets in supersonic, turbulent jets. Wave packets are large-scale turbulent structures that are correlated and advected over distances that are large compared to the integral scales of turbulence, i.e., many jet diameters at the lowest frequencies. They are thought to be responsible for the peak noise radiated at shallow angles to the jet axis. Linear wave packet models based on the Parabolized Stability Equations (PSE) have been shown in the past to be in excellent agreement with statistical structures educed from experimental pressure and velocity data in subsonic jets. Here, we extend these models to supersonic jets and validate them using a Large Eddy Simulation (LES) database for an isothermal and a moderately heated Mach 1.5 turbulent jets. For supersonic jets, inlet conditions for PSE models are ambiguous, as a parallel flow stability analysis shows several unstable modes at the inlet cross section. We develop a bi-orthogonal decomposition and project the LES data onto the relevant families of instability waves. These serve as inlet conditions, including the amplitude and shape functions, for PSE solutions which are then favorably compared to the near-field pressure fields educed from LES.
Self-diffusion of carbon dioxide in samaria/alumina aerogel catalyst using high field NMR diffusometry
Authors: Mueller Robert , Zhang Suihua , Neumann Björn , Bäumer Marcus , Vasenkov Sergey
Published: October 2013

Pulsed field gradient (PFG) NMR was used to investigate the self-diffusion of carbon dioxide in alumina stabilized samaria aerogel catalyst, a promising porous catalyst for gas-phase reactions featuring high porosity and high surface area. For diffusion studies, the catalyst was prepared in two sample packing types, macroscopic monoliths (i.e., macroscopic cylindrical particles) and powder beds with particle sizes around 200 μm that are considered for catalytic applications. Studies of diffusion in these samples revealed how macroscopic packing influences the catalyst transport properties. Application of a high magnetic field of 17.6 T in the reported PFG NMR studies enabled diffusion measurements for relatively low carbon dioxide densities in the catalyst samples corresponding to a gas loading pressure of around 0.1 atm. As a result, it was possible to perform diffusion measurements for a large range of carbon dioxide loading pressures between 0.1 and 10 atm. The measured carbon dioxide diffusivities in the beds of catalyst particles are interpreted in the context of a simple diffusion-mediated exchange model previously used for zeolites and other porous materials.
Probing energy transfer events in the light harvesting complex 2 (LH2) of Rhodobacter sphaeroides with two-dimensional spectroscopy
Authors: Fidler Andrew F. , Singh Ved P. , Long Phillip D. , Dahlberg Peter D. , Engel Gregory S.
Published: October 2013

Excitation energy transfer events in the photosynthetic light harvesting complex 2 (LH2) of Rhodobacter sphaeroides are investigated with polarization controlled two-dimensional electronic spectroscopy. A spectrally broadened pulse allows simultaneous measurement of the energy transfer within and between the two absorption bands at 800 nm and 850 nm. The phased all-parallel polarization two-dimensional spectra resolve the initial events of energy transfer by separating the intra-band and inter-band relaxation processes across the two-dimensional map. The internal dynamics of the 800 nm region of the spectra are resolved as a cross peak that grows in on an ultrafast time scale, reflecting energy transfer between higher lying excitations of the B850 chromophores into the B800 states. We utilize a polarization sequence designed to highlight the initial excited state dynamics which uncovers an ultrafast transfer component between the two bands that was not observed in the all-parallel polarization data. We attribute the ultrafast transfer component to energy transfer from higher energy exciton states to lower energy states of the strongly coupled B850 chromophores. Connecting the spectroscopic signature to the molecular structure, we reveal multiple relaxation pathways including a cyclic transfer of energy between the two rings of the complex.
Ion angular distribution in plasma of vacuum arc ion source with composite cathode and elevated gas pressure
Authors: Nikolaev A. G. , Savkin K. P. , Yushkov G. Yu. , Oks E. M.
Published: October 2013

The Metal Vapor Vacuum Arc (MEVVA) ion sources are capable of generating ion beams of almost all metals of the periodic table. For this kind of ion source, a combination of gas feeding with magnetic field allows the simultaneous generation of both metal and gaseous ions. That makes the MEVVA ion source an excellent instrument for science and application. This work presents results of investigation for ion angular distributions in vacuum arc plasma of Mevva-V.Ru ion source for composite cathodes and for elevated gas pressure. It was shown that for all the cathode materials, singly charged ions have wider angular distribution than multiply charged ions. Increasing the working gas pressure leads to a significant change in the angular distribution of gaseous ions, while with the distribution of metal ions gas remains practically unchanged. The reasons for such different influences are discussed.
The high-resolution infrared spectrum of DC4H from 450 to 1100 cm−1: Overtone, combination, and hot bands
Authors: Bizzocchi L. , Tamassia F. , Esposti C. Degli , Dore L. , Fusina L. , Villa M. , Canè E.
Published: October 2013

The high-resolution infrared spectrum of monodeuterated diacetylene has been recorded in the 450–1100 cm−1 spectral region by Fourier transform infrared spectroscopy. Seven new bands have been identified: the ν3 fundamental (C–C stretch), and the ν8 + ν9, ν7 + ν8, 2ν7, 2ν8, ν8 + ν9 − ν9, and ν6 + ν9 − ν9 combination, overtone, and hot bands. The assigned transitions, together with those previously reported for the fundamental bands [F. Tamassia, L. Bizzocchi, C. Degli Esposti, L. Dore, M. Di Lauro, L. Fusina, M. Villa, and E. Canè, Astron. Astrophys. 549, A38 (2013)], form a comprehensive data set which comprises more than 2500 ro-vibrational transitions, and involves all singly and most doubly excited vibrational states of DC4H lying below 1000 cm−1. Rotational and vibrational l-type resonance effects among the sub-levels of excited bending states were considered in the analysis, which also included a careful treatment of the various anharmonic interactions coupling many vibrational states lying above 600 cm−1. Reliable and unambiguous spectroscopic parameters were obtained for each investigated state, including the rotational and centrifugal distortion constants Bv and Dv, the l-type doubling parameter qt, the anharmonicity constants xL(89), xL(69), and the vibrational l-type terms r89, r69 for the v8 = v9 = 1 and v6 = v9 = 1 bend-bend combination states.
Reduction of plasma density in the Helicity Injected Torus with Steady Inductance experiment by using a helicon pre-ionization source
Authors: Hossack Aaron C. , Firman Taylor , Jarboe Thomas R. , Prager James R. , Victor Brian S. , Wrobel Jonathan S. , Ziemba Timothy
Published: October 2013

A helicon based pre-ionization source has been developed and installed on the Helicity Injected Torus with Steady Inductance (HIT-SI) spheromak. The source initiates plasma breakdown by injecting impurity-free, unmagnetized plasma into the HIT-SI confinement volume. Typical helium spheromaks have electron density reduced from (2–3) × 1019 m−3 to 1 × 1019 m−3. Deuterium spheromak formation is possible with density as low as 2 × 1018 m−3. The source also enables HIT-SI to be operated with only one helicity injector at injector frequencies above 14.5 kHz. A theory explaining the physical mechanism driving the reduction of breakdown density is presented.
3D numerical simulations of negative hydrogen ion extraction using realistic plasma parameters, geometry of the extraction aperture and full 3D magnetic field map
Authors: Mochalskyy S. , Wünderlich D. , Ruf B. , Franzen P. , Fantz U. , Minea T.
Published: October 2013

Decreasing the co-extracted electron current while simultaneously keeping negative ion (NI) current sufficiently high is a crucial issue on the development plasma source system for ITER Neutral Beam Injector. To support finding the best extraction conditions the 3D Particle-in-Cell Monte Carlo Collision electrostatic code ONIX (Orsay Negative Ion eXtraction) has been developed. Close collaboration with experiments and other numerical models allows performing realistic simulations with relevant input parameters: plasma properties, geometry of the extraction aperture, full 3D magnetic field map, etc. For the first time ONIX has been benchmarked with commercial positive ions tracing code KOBRA3D. A very good agreement in terms of the meniscus position and depth has been found. Simulation of NI extraction with different e/NI ratio in bulk plasma shows high relevance of the direct negative ion extraction from the surface produced NI in order to obtain extracted NI current as in the experimental results from BATMAN testbed.
Diffusivity and mobility of non-equilibrium carriers in organic semiconductors: Existence of critical field determining temperature dependence
Authors: Tripathi Durgesh C. , Sinha Dhirendra K. , Mohapatra Y. N.
Published: October 2013

The role of disorder in controlling diffusivity and mobility of charge-carriers in the hopping regime of transport within a potential landscape has become especially significant for organic semiconductors. The temperature and field dependence of diffusivity (D) and mobility (μ) of injected charge-carriers have been simultaneously measured using electroluminescence transients for representative organic thin-films of tris(8-hydroxyquinoline) aluminum (III) (Alq3) and poly(9,9-dioctylfluorenyl-2,7-diyl) (PFO). Significantly, the field dependence of diffusivity at different temperatures is similar except for a shift of a critical field beyond which it shows a sharp increase. The critical field is shown to be linearly decreasing with temperature ultimately vanishing at a characteristic limit T∗, and the slope is a measure of the localization length. The normalization of diffusivity is used to demonstrate the role of field in controlling temperature dependence. The scheme has been used to neatly decouple contributions from energetic (diagonal) and positional (off-diagonal) disorder thus enabling independent experimental determination of all the parameters of standard and correlated versions of Gaussian disorder model. The results demonstrate the validity of Gaussian disorder model even for non-equilibrium carriers, and that the parameters can be obtained with appropriate scaling of the field in such cases.
Characteristics of acetone cluster ion beam for surface processing and modification
Authors: Ryuto H. , Kakumoto Y. , Takeuchi M. , Takaoka G. H.
Published: October 2013

An acetone cluster ion beam was produced by the adiabatic expansion method without using helium as a support gas. The cluster source for the production of ethanol clusters was replaced with that sealed with metal gaskets. The Laval nozzle for the production of ethanol clusters was also replaced with a stainless steel conical nozzle. The cluster size distributions of the acetone cluster ion beams had mean values approximately at 2 × 103 molecules and increased with source pressure. The typical beam current density of the acetone cluster ion beam was approximately 0.5 μA/cm2.
Gold ion implantation into alumina using an “inverted ion source” configuration
Authors: Salvadori M. C. , Teixeira F. S. , Sgubin L. G. , Araujo W. W. R. , Spirin R. E. , Cattani M. , Oks E. M. , Brown I. G.
Published: October 2013

We describe an approach to ion implantation in which the plasma and its electronics are held at ground potential and the ion beam is injected into a space held at high negative potential, allowing considerable savings both economically and technologically. We used an “inverted ion implanter” of this kind to carry out implantation of gold into alumina, with Au ion energy 40 keV and dose (3–9) × 1016 cm−2. Resistivity was measured in situ as a function of dose and compared with predictions of a model based on percolation theory, in which electron transport in the composite is explained by conduction through a random resistor network formed by Au nanoparticles. Excellent agreement is found between the experimental results and the theory.
Modifications of the near-wall structures in thermally induced three-dimensional turbulent boundary layer
Authors: El-Samni O. A.
Published: October 2013

Statistical analysis is carried out in order to examine the modifications of near wall coherent structures in a thermally induced three-dimensional turbulent boundary layer (3DTBL). The buoyancy forces modify the counter rotating vortices in the near-wall region with different degrees in a similar way to that produced by the pressure and shear driven three-dimensional turbulent boundary layer flows. Evidence of such modifications that is highlighted in the present study may explain the reduction of Reynolds shear stress and turbulence activities in the near-wall region. It has been shown that the induced three-dimensionality weakens the strength of near-wall vortices in such a way that vortices of one sign are weakened to produce ejections and those of the other sign are weakened to produce sweeps. In contrast to the hypotheses explaining the reduction of turbulence activities in pressure and shear driven 3DTBL flows, vortices rotating in the same direction as the background mean spanwise vorticity in the near-wall region are weakened much more than those rotating in the opposite direction.
Effect of perpendicular uniaxial anisotropy on the annihilation fields of magnetic vortices
Authors: Novais E. R. P. , Allende S. , Altbir D. , Landeros P. , Garcia F. , Guimarães A. P.
Published: October 2013

The magnetization reversal in several nanoscopic systems is driven by the nucleation and propagation of a vortex structure that is very sensitive to the application of a magnetic field or a spin polarized current. In particular in a dot, the vortex profile is strongly affected by anisotropy, however, its role on the core behavior has not been clarified. In the present work, we investigate the influence of a perpendicular anisotropy on the annihilation and shape of magnetic vortex cores in permalloy disks. We used both micromagnetic simulations with the OOMMF code, and the analytical rigid core model that assumes that the shape of the core does not change during the hysteresis cycle. Under both approaches, the annihilation field decreases with increasing perpendicular anisotropy for almost all the structures investigated. Also a deformation of the vortex core profile is evidenced from the micromagnetic simulations, for larger anisotropy and/or dot thickness. For every dot thickness, this change does not depend on the dot radius, but on the relative distance of the core from the center of the dot.
Ultra-fast intensified frame images from an electron cyclotron resonance hydrogen plasma at 2.45 GHz: Some space distributions of visible and monochromatic emissions
Authors: Cortázar O. D. , Megía-Macías A. , Vizcaíno-de-Julián A. , Tarvainen O. , Komppula J. , Koivisto H.
Published: October 2013

First results from an ultra-fast frame image acquisition diagnostic coupled to a 2.45 GHz microwave hydrogen discharge are presented. The plasma reactor has been modified to include a transparent doubled shielded quartz window allowing to viewing the full plasma volume. Pictures describing the breakdown process at 1 μs exposure time have been obtained for integrated visible light signal, Balmer-alpha, Balmer-beta lines, and Fulcher-band. Several different plasma emission distributions are reported. The distribution depends on the magnetic field configuration, incident microwave power, and neutral gas pressure.
Comparison of amorphous silicon absorber materials: Light-induced degradation and solar cell efficiency
Authors: Stuckelberger M. , Despeisse M. , Bugnon G. , Schüttauf J.-W. , Haug F.-J. , Ballif C.
Published: October 2013

Several amorphous silicon (a-Si:H) deposition conditions have been reported to produce films that degrade least under light soaking when incorporated into a-Si:H solar cells. However, a systematic comparison of these a-Si:H materials has never been presented. In the present study, different plasma-enhanced chemical vapor deposition conditions, yielding standard low-pressure VHF a-Si:H, protocrystalline, polymorphous, and high-pressure RF a-Si:H materials, are compared with respect to their optical properties and their behavior when incorporated into single-junction solar cells. A wide deposition parameter space has been explored in the same deposition system varying hydrogen dilution, deposition pressure, temperature, frequency, and power. From the physics of layer growth, to layer properties, to solar cell performance and light-induced degradation, a consistent picture of a-Si:H materials that are currently used for a-Si:H solar cells emerges. The applications of these materials in single-junction, tandem, and triple-junction solar cells are discussed, as well as their deposition compatibility with rough substrates, taking into account aspects of voltage, current, and charge collection. In sum, this contributes to answering the question, “Which material is best for which type of solar cell?”
Non-linear magnetohydrodynamic modeling of plasma response to resonant magnetic perturbations
Authors: Orain F. , Bécoulet M. , Dif-Pradalier G. , Huijsmans G. , Pamela S. , Nardon E. , Passeron C. , Latu G. , Grandgirard V. , Fil A. , Ratnani A. , Chapman I. , Kirk A. , Thornton A. , Hoelzl M. , Cahyna P.
Published: October 2013

The interaction of static Resonant Magnetic Perturbations (RMPs) with the plasma flows is modeled in toroidal geometry, using the non-linear resistive MHD code JOREK, which includes the X-point and the scrape-off-layer. Two-fluid diamagnetic effects, the neoclassical poloidal friction and a source of toroidal rotation are introduced in the model to describe realistic plasma flows. RMP penetration is studied taking self-consistently into account the effects of these flows and the radial electric field evolution. JET-like, MAST, and ITER parameters are used in modeling. For JET-like parameters, three regimes of plasma response are found depending on the plasma resistivity and the diamagnetic rotation: at high resistivity and slow rotation, the islands generated by the RMPs at the edge resonant surfaces rotate in the ion diamagnetic direction and their size oscillates. At faster rotation, the generated islands are static and are more screened by the plasma. An intermediate regime with static islands which slightly oscillate is found at lower resistivity. In ITER simulations, the RMPs generate static islands, which forms an ergodic layer at the very edge (ψ≥0.96) characterized by lobe structures near the X-point and results in a small strike point splitting on the divertor targets. In MAST Double Null Divertor geometry, lobes are also found near the X-point and the 3D-deformation of the density and temperature profiles is observed.
Shock compression of aluminum single crystals to 70 GPa: Role of crystalline anisotropy
Authors: Choudhuri D. , Gupta Y. M.
Published: October 2013

Crystalline anisotropy effects were examined at high stresses by shock compressing Al single crystals along ⟨100⟩, ⟨110⟩, and ⟨111⟩ orientations to peak stresses ranging from 40 to 70 GPa. Laser-interferometry was used to monitor particle velocity histories, including unloading wave profiles. A single, flat-top shock wave followed by a structured release was observed in all the experiments. Shock velocities and longitudinal sound speeds (onset of release) were also determined from the measured particle velocity histories. Within experimental uncertainty (1%–2%), the Hugoniots for the three orientations were indistinguishable, and a single longitudinal stress-density curve was fit to all peak state data. In contrast, the longitudinal sound speeds (and the resulting longitudinal elastic moduli) in the shocked state showed crystal anisotropy effects over the entire stress range examined (up to ∼50% density compression). The measured longitudinal elastic moduli at the highest stress represent more than a fourfold increase from the ambient value and showed continuing anisotropy with compression. The present findings show that Hugoniots may not be the optimal measure of crystalline anisotropy, and even low-anisotropy single crystals, like Al, can manifest significant anisotropy in elastic moduli at large shock compressions.
Wireless passive polymer-derived SiCN ceramic sensor with integrated resonator/antenna
Authors: Li Yan , Yu Yuxi , San Haisheng , Wang Yansong , An Linan
Published: October 2013

This paper presents a passive wireless polymer-derived silicon carbonitride (SiCN) ceramic sensor based on cavity radio frequency resonator together with integrated slot antenna. The effect of the cavity sensor dimensions on the Q-factor and resonant frequency is investigated by numerical simulation. A sensor with optimal dimensions is designed and fabricated. It is demonstrated that the sensor signal can be wirelessly detected at distances up to 20 mm. Given the high-temperature stability of the SiCN, the sensor is very promising for high-temperature wireless sensing applications.
Direct measurements of collisional Raman line broadening in the S-branch transitions of acetylene (C2H2)
Authors: Hsu Paul S. , Stauffer Hans U. , Jiang Naibo , Gord James R. , Roy Sukesh
Published: October 2013

We report direct measurements of the self- and N2-broadened Raman S-branch linewidths of acetylene (C2H2), obtained by employing time-resolved picosecond rotational coherent anti-Stokes Raman scattering spectroscopy. Using broadband 115-ps pump and Stokes pulses (∼135 cm−1 bandwidth) and a spectrally narrowed 90-ps probe pulse (∼0.2 cm−1 bandwidth), Raman-coherence lifetimes are measured at room temperature for the S-branch (ΔJ = +2) transitions associated with rotational quantum number J = 3–25. These directly measured Raman-coherence lifetimes, when converted to collisional linewidth broadening coefficients, differ from the previously reported broadening coefficients extracted from theoretical calculations by 6%–35% for self-broadening for C2H2 and by up to 60% for N2-broadened C2H2.
Distinct dynamical and structural properties of a core-softened fluid when confined between fluctuating and fixed walls
Authors: Krott Leandro B. , Bordin José Rafael
Published: October 2013

Molecular dynamics simulations were used to study the structural and dynamical properties of a water-like core-softened fluid under confinement when the confining media is rigid or fluctuating. The fluid is modeled using a two-length scale potential that reproduces, in the bulk, the anomalous behavior observed in water. We perform simulations in the NVT ensemble for fixed flat walls and in the NpT ensemble using a fluctuating wall control of pressure to study how the fluid behavior is affected by fixed and non-fixed walls. Our results indicate that the dynamical and structural properties of the fluid are strongly affected by the wall mobility.
Reduced electron temperature in a magnetized inductively-coupled plasma with internal coil
Authors: Arancibia Monreal J. , Chabert P. , Godyak V.
Published: October 2013

The effect of magnetic filtering on the electron energy distribution function is studied in an inductive discharge with internal coil coupling. The coil is placed inside the plasma and driven by a low-frequency power supply (5.8 MHz) which leads to a very high power transfer efficiency. A permanent dipole magnet may be placed inside the internal coil to produce a static magnetic field around 100 Gauss. The coil and the matching system are designed to minimize the capacitive coupling to the plasma. Capacitive coupling is quantified by measuring the radiofrequency (rf) plasma potential with a capacitive probe. Without the permanent magnet, the rf plasma potential is significantly smaller than the electron temperature. When the magnet is present, the rf plasma potential increases. The electron energy distribution function is measured as a function of space with and without the permanent magnet. When the magnet is present, electrons are cooled down to low temperature in the downstream region. This region of low electron temperature may be useful for plasma processing applications, as well as for efficient negative ion production.
Effects of electron temperature and electron flow on O-X conversion
Authors: Jia Guo-Zhang , Gao Zhe , Zhao Ai-Hui
Published: October 2013

Effects of electron temperature and electron flow on Ordinary-Extraordinary (O-X) conversion in the range of electron cyclotron frequency are investigated. The modified optimal parallel refraction index, Nzc, and the conversion coefficient are obtained analytically from the kinetic dispersion relation. The presence of finite electron temperature shifts the O-X conversion layer towards a region of lower density and increases the value of Nzc; while the effect of electron flow depends on its direction with respect to the parallel wave vector. When the electron flow is along the parallel wave vector, Nzc will be increased and the effects of finite electron temperature and finite electron flow accumulate. As a result, a more oblique incidence angle is required for efficient O-X conversion. For typical Tokamak plasmas, the efficiency of O-X conversion will decrease without the consideration of the two effects. When the electron flow is in the direction opposite to the parallel wave vector, the two effects compete, even cancel each other.