bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluating the accuracy of tooth color measurement by combining the Munsell color system and dental colorimeter
Authors: Chang Jiun‐Yao , Chen Wen‐Cheng , Huang Ta‐Ko , Wang Jen‐Chyan , Fu Po‐Sung , Chen Jeng‐Huey , Hung Chun‐Cheng
Published: July 2012

As we pay increasing attention to dental aesthetics, tooth color matching has become an important part of daily dental practice. This aim of this study was to develop a method to enhance the accuracy of a tooth color matching machine. The Munsell color tabs in the range of natural human teeth were measured using a tooth color measuring machine (ShadeEye NCC). The machine's accuracy was analyzed using an analysis of variance test and a Tukey post‐hoc test. When matching the Munsell color tabs with the ShadeEye NCC colorimeter, settings of Chroma greater than 6 and Value less than 4 showed unacceptable clinical results. When the CIELAB mode was used, the a* value (which represents the red–green axis in the Commission Internationale de l'Eclairage color space) made no significant difference (p = 0.84), the L* value (which represents the lightness) resulted in a negative correlation, and the b* value (which represents the yellow–blue axis) resulted in a positive correlation with ΔE. When the Munsell color tabs and the Vitapan were measured in the same mode and compared, the inaccuracies showed that the Vitapan was not a proper tool for evaluating the stability and accuracy of ShadeEye NCC. By knowing the limitations of the machine, we evaluated the data using the Munsell color tabs; shade beyond the acceptable range should be reevaluated using a visual shade matching method, or if measured by another machine, this shade range should be covered to obtain more accurate results.
Lymphoepithelioma‐like carcinoma of ureter—A rare case report and review of the literature
Authors: Wen Sheng‐Chen , Shen Jung‐Tsung , Jang Mei‐Yu , Tsai Kun‐Bow , Chang Shu‐Fang , Tsai Li‐Jiun , Wu Wen‐Jeng
Published: July 2012

Lymphoepithelioma‐like carcinoma (LELC) is best known to occur in the nasopharynx. When LELC occurs in the urinary tract, this extremely rare neoplasm most commonly affects the bladder but has also been reported in the renal pelvis, ureter, prostate [1], and urethra [2]. We present a case of LELC arising in the right proximal ureter of a 64‐year‐old male patient with hydronephrosis and nausea. Computed tomography demonstrated right ureter tumor. On biopsy, the patient was diagnosed with infiltrating urothelial carcinoma. An operation consisting of right nephroureterectomy and bladder cuff removal was carried out. The pathologic examination showed pure subtype of LELC, pT3N0. Unlike lymphoepithelioma in the nasopharynx, immunohistochemical analysis of this urinary LELC was negative for the Epstein–Barr virus. No disease progression was noted at 6 months’ follow‐up. Only eight previous cases of LELC involving the ureter have been reported, and a review of the available literature and a summary of ureter cases are presented here. This is the first report of a ureteral LELC case and third urothelial LELC cases [3] in Taiwan.
Major food safety episodes in Taiwan: Implications for the necessity of international collaboration on safety assessment and management
Authors: Li Jih‐Heng , Yu Wen‐Jing , Lai Yuan‐Hui , Ko Ying‐Chin
Published: July 2012

The major food safety episodes that occurred in Taiwan during the past decade are briefly reviewed in this paper. Among the nine major episodes surveyed, with the exception of a U.S. beef (associated with Creutzfeldt–Jakob disease)‐related incident, all the others were associated with chemical toxicants. The general public, which has a layperson attitude of zero tolerance toward food safety, may panic over these food‐safety‐associated incidents. However, the health effects and impacts of most incidents, with the exception of the melamine incident, were essentially not fully evaluated. The mass media play an important role in determining whether a food safety concern becomes a major incident. A well‐coordinated and harmonized system for domestic and international collaboration to set up standards and regulations is critical, as observed in the incidents of pork with ractopamine, Chinese hairy crab with nitrofuran antibiotics, and U.S. wheat with malathion. In the future, it can be anticipated that food safety issues will draw more attention from the general public. For unknown new toxicants or illicit adulteration of food, the establishment of a more proactive safety assessment system to monitor potential threats and provide real‐time information exchange is imperative.
Ethische Aspekte epidemiologischer Forschung
Authors: Schröder-Bäck Peter , Brall Caroline
Published: July 2012

Einleitung

Ethischen Aspekten wird in der Epidemiologie angesichts der zahlreichen ethischen Herausforderungen des Forschers gegenüber Probanden und Gesellschaft immer mehr Beachtung geschenkt. Mit Wissen über ethische Normen (z.B. Autonomierespekt, Gerechtigkeit, Gesundheitsmaximierung) und Methoden können Konflikte in der Forschung besser erkannt und erörtert werden. Deswegen sollte Ethik auch fester Bestandteil epidemiologischer Ausbildung sein.
Epidemiologische Fachgesellschaften in Deutschland
Authors: Zeeb Hajo
Published: July 2012

Einleitung

Die Epidemiologie hat in Deutschland in den vergangenen Jahrzehnten einen erheblichen Aufschwung erfahren, was sich u.a. in einer wachsenden Zahl epidemiologischer Forschungsinstitute, besseren Ausbildungsmöglichkeiten und einer größeren Präsenz der epidemiologischen Wissenschaftler in der (Fach-) Öffentlichkeit äußert. Die Professionalisierung der Epidemiologie in Deutschland spiegelt sich auch in Wachstum und Ausdifferenzierung der epidemiologischen Fachgesellschaften wider.
Epidemiology of dementia – A current overview
Authors: Luck Tobias , Luppa Melanie , Riedel-Heller Steffi G.
Published: July 2012

Dementia is common and one of the most burdensome diseases for sufferers and their relatives; it is also one of the biggest challenges for the healthcare systems of aging societies. Professional nursing care and informal care by family or friends constitute the most significant cost components of dementia. In the absence of effective therapeutic options, a healthy lifestyle might be the best option to reduce the individual risk of developing dementia.
META-INDUCTION IN EPISTEMIC NETWORKS AND THE SOCIAL SPREAD OF KNOWLEDGE
Authors: Schurz Gerhard
Published: July 2012

Indicators of the reliability of informants are essential for social learning in a society that is initially dominated by ignorance or superstition. Such reliability indicators should be based on meta-induction over records of truth-success. This is the major claim of this paper, and it is supported in two steps. (1) One needs a non-circular justification of the method of meta-induction, as compared to other (non-inductive) learning methods. An approach to this problem (a variant of Hume's problem) has been developed in earlier papers and is reported in section 2. It is based on the predictive optimality of meta-inductive learning, under the assumption that objective success records are globally available. (2) The rest of the paper develops an extension of this approach, so-called local meta-induction. Here individuals can access only success records of individuals in their immediate epistemic neighborhood. It is shown that local meta-inductive learning can spread reliable information over the entire population, and has clear advantages compared to success-independent social learning methods such as peer-imitation and authority-imitation.
Towards a new typology of coordinatedwh-questions
Authors: CITKO BARBARA , GRAČANIN-YUKSEK MARTINA
Published: July 2012

In this paper, we develop a new typology of multiplewh-questions with coordinatedwh-pronouns. We motivate the existence of three distinct structures for such questions: one mono-clausal and two bi-clausal. We use four kinds of diagnostics to determine which of the three structures is available in a particular language: the availability of both multiplewh-questions andwh-questions with coordinatedwh-pronouns, coordination of two argumentwh-phrases, transitivity restrictions and superiority effects.
Śiva and Avalokiteśvara: On the iconography and date of the Golden Window and Golden Door of Patan's Royal Palace
Authors: Bühnemann Gudrun
Published: July 2012

The Golden Window above the Golden Door of Caukoṭ Darbār, a building on the western side of the (former) Royal Palace complex, is a major attraction in the city of Patan (Nepal). The gilt window panel features a representation of Avalokiteśvara in his form as Sṛṣṭikartā (“creator”) emanating Hindu divinities from his body. The sides, base and tympanum of the window likewise display Hindu divinities. The construction of the window has been ascribed to different kings of the late Malla period (1483–1768) and is said to illustrate their support for the Buddhist practices of their subjects, while providing a Hindu interpretative framework for such practices. In this paper I identify the divinities on the window and examine textual and visual sources that shed light on the date of the window's construction, including the inscriptions above and at the sides of the Golden Door. I show that there is no evidence for such an early dating of the window and that the Golden Window was probably constructed sometime in the nineteenth century in either the Śāh period (1769–1846) or, more likely, the Rāṇā period (1846–1951). I conclude with some thoughts on the possible significance of the peculiar configuration of divinities surrounding the Bodhisattva on the window.
Genetic and neurocognitive contributions to the development of psychopathy
Authors: Viding Essi , McCrory Eamon J.
Published: July 2012

An overview is provided of recent twin, molecular genetic, and magnetic resonance imaging studies that are helping to inform a model of developmental vulnerability to adult psychopathy. Although the current evidence base suggests that children with high levels of callous–unemotional traits are genetically and neurocognitively vulnerable to developing psychopathic and antisocial behaviors, existing research also clearly indicates that environmental influences play an important role. One potential implication is that interventions for children with antisocial behavior and callous–unemotional traits may need to be tailored to take into account their distinct pattern of neurocognitive vulnerability, as revealed by developmental neuroimaging studies. Specifically, interventions that pursue punishment-oriented or explicit empathy induction strategies may be less effective with this group of antisocial children. By contrast, preliminary evidence suggests that enhancing positive parenting and parental involvement, as well as applying consistent rewards may represent more promising intervention approaches.
Crucial surviving aspects for vitrified in vitro-produced bovine embryos
Authors: Sudano Mateus José , Paschoal Daniela Martins , da Silva Rascado Tatiana , Crocomo Letícia Ferrari , Magalhães Luis Carlos Oña , Junior Alício Martins , Machado Rui , da Cruz Landim-Alvarenga Fernanda
Published: July 2012

The objective of the present study was to correlate some parameters (cleavage, blastocyst production, quality degree score, total cell number, fresh apoptosis and lipid content) with embryo survival after cryopreservation. A total of 1727 in vitro-produced bovine blastocysts were used to establish the parameters (mean ± standard error of the mean (SEM)) for cleavage (85.6 ± 0.8), blastocyst production (39.9 ± 1.4), quality degree score (1.6 ± 0.1), total cell number (140.1 ± 2.9), fresh apoptosis (20.8 ± 1.1) and lipid content (21.3 ± 0.8 droplets). On the same way 1316 blastocysts were vitrified for the determination of post-cryopreservation embryo survival (49.4 ± 1.9). Fresh apoptosis rate and total lipid droplets value were correlated (P < 0.05) with embryo survival after cryopreservation (r = 0.91 and r = 0.59; respectively). However, cleavage, blastocyst production, quality degree score and total cell number were not correlated (P > 0.05) with embryo cryotolerance (r = 0.23, r = 0.38, r = 0.22 and r = 0.28; respectively). Therefore, the increased lipid content was moderately correlated with apoptosis in vitrified blastocysts. On the other hand, increased apoptosis in fresh blastocysts was strongly correlated with apoptosis in vitrified blastocysts, which indicated that the apoptosis rate in fresh embryos was a better parameter than the lipid content to predict post-vitrification embryo survival.
The role of groundwater in the Amazon water cycle: 2. Influence on seasonal soil moisture and evapotranspiration
Authors: Miguez‐Macho Gonzalo , Fan Ying
Published: July 2012

We investigate the potential influence of groundwater on seasonal evapotranspiration (ET) in the Amazon using a coupled groundwater‐surface water model (LEAF‐Hydro‐Flood) forced with ERA‐Interim reanalysis, at 2 km grid and 4 min steps over 11 yrs (2000–2010), and validated with available soil moisture and ET observations. We find that first, the simulated water table is <2 m deep over a significant portion of the Amazon (20–40%). Second, shallow groundwater can reduce wet season soil drainage, leading to larger soil water stores before the dry season arrives. Third, capillary rises from the water table can reach the root zone and maintain high dry season ET near the valleys. Fourth, groundwater's delayed response to rainfall can buffer surface stress in the dry season, when groundwater is the shallowest. Fifth, this temporal delay can be seen as spatial patterns; continued drainage and convergence maintain moist valleys forming a structured mosaic of wet‐dry patches in the dry season. Results from two parallel runs, with and without groundwater, suggest that overall groundwater made a large difference in modeled soil moisture where the water table is shallow, but it only made a difference in modeled ET where the seasonality is strong; over southeastern Amazonia, July–August ET differs by ∼1 mm/day. We note that our results are based on model simulations, which only suggest the potential importance of the groundwater system to the Amazon water cycle. The ultimate knowledge must come from carefully designed field observations linking vegetation, soil and groundwater with water balance studies and tracer tests, across a range of physical‐biological settings.
On the complete integrability of a nonlinear oscillator from group theoretical perspective
Authors: Bhuvaneswari A. , Chandrasekar V. K. , Senthilvelan M. , Lakshmanan M.
Published: July 2012

In this paper, we investigate the integrability aspects of a physically important nonlinear oscillator which lacks sufficient number of Lie point symmetries but can be integrated by quadrature. We explore the hidden symmetry, construct a second integral, and derive the general solution of this oscillator by employing the recently introduced λ-symmetry approach and thereby establish the complete integrability of this nonlinear oscillator equation from a group theoretical perspective.
Theory of light-induced deformation of azobenzene elastomers: Influence of network structure
Authors: Toshchevikov V. P. , Saphiannikova M. , Heinrich G.
Published: July 2012

Azobenzene elastomers have been extensively explored in the last decade as photo-deformable smart materials which are able to transform light energy into mechanical stress. Presently, there is a great need for theoretical approaches to accurately predict the quantitative response of these materials based on their microscopic structure. Recently, we proposed a theory of light-induced deformation of azobenzene elastomers using a simple regular cubic network model [V. Toshchevikov, M. Saphiannikova, and G. Heinrich, J. Phys. Chem. B 116, 913 (2012)10.1021/jp206323h]. In the present study, we extend the previous theory using more realistic network models which take into account the random orientation of end-to-end vectors of network strands as well as the molecular weight distribution of the strands. Interaction of the chromophores with the linearly polarized light is described by an effective orientation potential which orients the chromophores perpendicular to the polarization direction. We show that both monodisperse and polydisperse azobenzene elastomers can demonstrate either a uniaxial expansion or contraction along the polarization direction. The sign of deformation (expansion/contraction) depends on the orientation distribution of chromophores with respect to the main chains which is defined by the chemical structure and by the lengths of spacers. The degree of cross-linking and the polydispersity of network strands do not affect the sign of deformation but influence the magnitude of light-induced deformation. We demonstrate that photo-mechanical properties of mono- and poly-disperse azobenzene elastomers with random spatial distribution of network strands can be described in a very good approximation by a regular cubic network model with an appropriately chosen length of the strands.
Heavy-fermion instability in double-degenerate plasmas
Authors: Akbari-Moghanjoughi M.
Published: July 2012

In this work, we study the propagations of normal frequency modes for quantum hydrodynamic waves in the linear limit and introduce a new kind of instability in a double-degenerate plasma. Three different regimes, namely, low, intermediate, and high magnetic field strengths are considered which span the applicability of the work to a wide variety of environments. Distinct behavior is observed for different regimes, for instance, in the laboratory-scale field regime no frequency-mode instability occurs unlike those of intermediate and high magnetic-field strength regimes. It is also found that the instability of this kind is due to the heavy-fermions which appear below a critical effective-mass parameter (μcr=3) and that the responses of the two (lower and upper frequency) modes to fractional effective-mass change in different effective-mass parameter ranges (below and above the critical value) are quite opposite to each other. It is shown that the heavy-fermion instability due to extremely high magnetic field such as that encountered for a neutron-star crust can lead to confinement of stable propagations in both lower and upper frequency modes to the magnetic poles. Current study can have important implications for linear wave dynamics in both laboratory and astrophysical environments possessing high magnetic fields.
Quantal effects and MaxEnt
Authors: Holik F. , Plastino A.
Published: July 2012

Convex operational models (COMs) are considered as great extrapolations to larger settings of any statistical theory. In this article, we generalize the maximum entropy principle (MaxEnt) of Jaynes’ to any COM. After expressing MaxEnt in a geometrical and lattice theoretical setting, we are able to cast it for any COM. This scope-amplification opens the door to a new systematization of the principle and sheds light into its geometrical structure.
Development of the ITER magnetic diagnostic set and specification
Authors: Vayakis G. , Arshad S. , Delhom D. , Encheva A. , Giacomin T. , Jones L. , Patel K. M. , Pérez-Lasala M. , Portales M. , Prieto D. , Sartori F. , Simrock S. , Snipes J. A. , Udintsev V. S. , Watts C. , Winter A. , Zabeo L.
Published: July 2012

ITER magnetic diagnostics are now in their detailed design and R&D phase. They have passed their conceptual design reviews and a working diagnostic specification has been prepared aimed at the ITER project requirements. This paper highlights specific design progress, in particular, for the in-vessel coils, steady state sensors, saddle loops and divertor sensors. Key changes in the measurement specifications, and a working concept of software and electronics are also outlined.
Reading and writing charge on graphene devices
Authors: Connolly M. R. , Herbschleb E. D. , Puddy R. K. , Roy M. , Anderson D. , Jones G. A. C. , Maksym P. , Smith C. G.
Published: July 2012

We use a combination of charge writing and scanning gate microscopy to map and modify the local charge neutrality point of graphene field-effect devices. We give a demonstration of the technique by writing remote charge in a thin dielectric layer over a graphene-metal interface and detecting a shift in the local charge neutrality point. We perform electrostatic simulations to characterize the interaction between a realistic scanning probe tip, the deposited charge, and the graphene and find a good semi-quantitative agreement with the experimental results.
Pulse energy measurement at the hard x-ray laser in Japan
Authors: Kato M. , Tanaka T. , Kurosawa T. , Saito N. , Richter M. , Sorokin A. A. , Tiedtke K. , Kudo T. , Tono K. , Yabashi M. , Ishikawa T.
Published: July 2012

The pulse energies of a free electron laser have accurately been measured in the hard x-ray spectral range. In the photon energy regime from 4.4 keV to 16.8 keV, pulse energies up to 100 μJ were obtained at the hard x-ray laser facility SACLA (SPring-8 Ångstrom Compact free-electron LAser). Two independent methods, using a cryogenic radiometer and a gas monitor detector, were applied and agreement within 3.3% was achieved. Based on our validated pulse energy measurement, a SACLA online monitor detector could be calibrated for all future experiments.
Ternary eutectic growth of nanostructured thermoelectric Ag-Pb-Te materials
Authors: Wu Hsin-jay , Foo Wei-jian , Chen Sinn-wen , Jeffrey Snyder G.
Published: July 2012

Nanostructured Ag-Pb-Te thermoelectric materials were fabricated by unidirectionally solidifying the ternary Ag-Pb-Te eutectic and near-eutectic alloys using the Bridgeman method. Specially, the Bridgman-grown eutectic alloy exhibited a partially aligned lamellar microstructure, which consisted of Ag5Te3 and Te phases, with additional 200-600 nm size particles of PbTe. The self-assembled interfaces altered the thermal and electronic transport properties in the bulk Ag-Pb-Te eutectic alloy. Presumably due to phonon scattering from the nanoscale microstructure, a low thermal conductivity (κ = 0.3 W/mK) was achieved of the eutectic alloy, leading to a zT peak of 0.41 at 400 K.
Substrate orientation dependent fine structure splitting of symmetric In(Ga)As/GaAs quantum dots
Authors: Treu J. , Schneider C. , Huggenberger A. , Braun T. , Reitzenstein S. , Höfling S. , Kamp M.
Published: July 2012

We present a comparative investigation of the fine structure splitting (FSS) from self-organized In(Ga)As quantum dots (QDs) grown on GaAs substrates with different lattice orientations. QDs grown on (111)B- and (112) oriented substrates are analyzed and compared to small QDs on commonly used (001) substrates. Mean values for the FSS as low as (5.6 ± 0.6) μeV are obtained for QDs on (111)B-GaAs, comparing favorably to the other two approaches ((11.8 ± 1.7) μeV for (112)-surfaces and (14.0 ± 2.2) μeV for (001)-surfaces). Single photon emission from (111)B QDs grown by droplet epitaxy is demonstrated via photon autocorrelation studies with a g(2)(0) value of 0.07.
Observation of magnetic domain-wall dynamics transition in Co/Ni multilayered nanowires
Authors: Kim Kab-Jin , Chiba D. , Kobayashi K. , Fukami S. , Yamanouchi M. , Ohno H. , Je Soong-Geun , Choe Sug-Bong , Ono T.
Published: July 2012

We observe a transition of domain-wall (DW) dynamics in ferromagnetic wires made of Co/Ni multilayers by use of transport measurement. As the wire width reduces, DW dynamics exhibits a transition from dendrite growth to pure DW motion. The threshold width is found to be about 300 nm and strongly depends on the relative dragging direction of the magnetic field and the current on DW: parallel (antiparallel) direction results in much smaller (larger) threshold width. It should be considered as a building block for DW-motion-based device applications.
Molecular-scale bio-sensing using armchair graphene
Authors: Chowdhury R. , Scarpa F. , Adhikari S.
Published: July 2012

We evaluate the transport properties performance of armchair graphene nanoribbons (AGNRs) with a bio-molecule assembly as potential molecular-scale biosensors (Anthracene). The bio-molecules are assumed to be absorbed at the edge of an AGNR, and to behave as quasi-1D systems. The transport spectrum and density of states (DOS) are calculated using a single-band tight-binding Hamiltonian representation, and a non-equilibrium Greens function formalism. Doping with boron and nitride atoms and its impact on the transport properties has also been evaluated. Significant changes in transmission and increase in DOS by 200% are observed when the Anthracene molecule is interacting with the AGNR. Boron and Nitrogen doping allow to increase current flows at constant voltage by 50% on average. There results suggest potential significant scope on using AGNRs for bio-devices based on either conductance or electroluminescence.
Magnetic reorientation and thermal stability in MnAs/GaAs (100) micro patterns driven by size effects
Authors: Tortarolo M. , Fernandez Baldis F. , Sirena M. , Steren L. B. , Milano J. , Etgens V. H. , Eddrief M. , Faini G.
Published: July 2012

Size effects and their consequences in the thermal stability of the magnetization of the micro-sized MnAs/GaAs(100) ribbons were studied by magnetic force microscopy. We found out that the orientation in which size is reduced plays a key role in the magnetic configuration and thermal stability of the micro-sized patterns. On the one hand, when reducing the size in the [0001] α-MnAs direction, the system shows an improvement in the thermal stability of the remanent magnetization. On the other hand, when the size is reduced in the [11-20] α-MnAs direction, the system goes through a magnetic reconfiguration from in-plane magnetized to out-of-plane magnetized, which also improves the thermal stability.
Increased dissipation from distributed etch holes in a lateral breathing mode silicon micromechanical resonator
Authors: Tu Cheng , Lee Joshua E.-Y.
Published: July 2012

Etch holes are commonly used design features when fabricating silicon-on-insulator micromechanical resonators to realize free standing structures. This paper shows that including etch-holes in a square-extensional mode resonator results in marked reduction of quality factor (Q) by 75%. The cause of this drop is explained by our finite element model used to theoretically estimate Q. These theoretical estimates agree well with measurement results. Our analyses show that anchor loss is dominant in a plain structure while etch holes increase thermoelastic damping to the point where both dissipation factors become comparable in determining the actual Q.
Note: Electrical and thermal characterization of a ferroelectric thin film with an electro-thermal nanoprobe
Authors: Jackson R. , Fletcher P. C. , Jambunathan K. , Damodaran A. R. , Emmerich J. N. , Teng H. , Martin L. W. , King W. P. , Wu Y.
Published: July 2012

The localized temperature-dependent piezoelectric response of ferroelectric barium strontium titanate (BST) thin films is studied using an electro-thermal (ET) nanoprobe. The ET probe provides independent electrical and thermal excitation to a nanometer-scale volume of the specimen and is capable of detecting the phase transition temperature of the BST thin films. The piezoresponse measured by the ET probe follows the temperature dependence of the piezoelectric constant, whereas with bulk heating the response follows the temperature dependence of the spontaneous polarization. The observed differences stem from the localized inhomogeneous electro-thermal field distribution at the specimen.
Pressure-induced phase transition and mechanical properties of molybdenum diboride: First principles calculations
Authors: Zhang Meiguang , Yan Haiyan , Wei Qun , Wang Hui
Published: July 2012

Using newly developed particle swarm optimization algorithm on crystal structural prediction, we first predicted that MoB2 undergoes a phase transition from the low-pressure rhombohedral phase to a tetragonal α-ThSi2-type phase with a volume drop of 4.01% when the applied pressure is 68 GPa. Phonon calculations suggest the α-ThSi2-type phase can be quenchable to ambient pressure. Then, Young’s modulus E and shear modulus G as a function of crystal orientation for the α-ThSi2-MoB2 have been systematically investigated. Further mechanical properties demonstrated that α-ThSi2-MoB2 possesses large bulk modulus of 322.3 GPa and high Vickers hardness of 32.1 GPa, exceeding the hardness of α-SiO2 (30.6 GPa) and β-Si3N4 (30.3 GPa). The excellent mechanical properties are attributed to the three-dimensional networks linked by strong covalent B-B bonding and Mo-B covalent bonds in MoB12 polyhedrons.
Origin of n-type conductivity of Sn-doped Mg2Si from first principles
Authors: Han Xiaoping , Shao Guosheng
Published: July 2012

The origin of the n-type properties of Sn-doped Mg2Si was investigated using a first-principles method in the framework of the density-functional theory. Extensive effort was made to elaborate the effect of Sn doping and the interaction between the doped Sn with possible native defects in Mg2Si. Such interaction is pivotal for the improved electrical properties of Sn doped Mg2Si, so that the experimentally observed n-type conductivity is attributed to the presence of interstitial Mg in Sn-doped Mg2Si. The tendency for the presence of defects in Mg2Si is examined through detailed thermodynamic and kinetic analyses.
Intrinsic dielectric frequency dependent spectrum of a single domain tetragonal BaTiO3
Authors: Liu Shuangyi , Huang Limin , Li Jackie , O'Brien Stephen
Published: July 2012

The intrinsic dielectric frequency dependent spectrum of single domain barium titanate (BaTiO3) at room temperature is investigated by considering the vibration of phonons and the conductivity of the tetragonal system in a wide frequency range up to THz. The proposed model combines Debye type of dissipation, soft mode theory, and the influence of conductivity on the dielectric loss to obtain a more precise dielectric frequency spectrum. The calculated results were compared with experimental data on single domain nanocrystals of BaTiO3, both free standing and suspended in a low dielectric medium. The comparisons provide insight into the mechanism for the dielectric behavior, which can be extended to apply to a range of composites that comprise single domain dielectrics embedded in continuous media. At the lower frequency range, conductivity plays a dominant role in the contribution to the dielectric loss along both a- and c-axes, while the phonon vibration controls the dielectric behavior of the system at higher frequency range. When the conductivity of the system increases, the dielectric loss increases below the MHz range, with such an effect diminishing when the frequency reaches the GHz regime.
Sensitive gas sensor embedded in a vertical polymer space-charge-limited transistor
Authors: Zan Hsiao-Wen , Li Chang-Hung , Yu Chih-Kuan , Meng Hsin-Fei
Published: July 2012

We report a very sensitive gas sensor embedded in a vertical polymer space-charge-limited transistor. The oxidizing and reducing gases act as electron dedoping and electron doping agents on the transistor active layer to change the potential distribution in the vertical channel and hence to change the output current density. With a 30-ppb detection limit to ammonia, the sensor can be used for non-invasive breath monitor in point-of-care applications. The integration of a sensitive gas sensor and a low-operation-voltage transistor in one single device also facilitates the development of low-cost and low-power-consumption sensor array.
Highly efficient inverted top-emitting green phosphorescent organic light-emitting diodes on glass and flexible substrates
Authors: Najafabadi E. , Knauer K. A. , Haske W. , Fuentes-Hernandez C. , Kippelen B.
Published: July 2012

Green phosphorescent inverted top-emitting organic light-emitting diodes with high current efficacy and luminance are demonstrated on glass and polyethersulfone (PES) substrates coated with polyethylene dioxythiophene-polystyrene sulfonate (PEDOT:PSS). The bottom cathode is an aluminum/lithium fluoride bilayer that injects electrons efficiently into an electron transport layer of 1,3,5-tri(m-pyrid-3-yl-phenyl)benzene (TpPyPB). The cathode is found to be highly sensitive to the exposure of trace amounts of O2 and H2O. A high current efficacy of 96.3 cd/A is achieved at a luminance of 1387 cd/m2 when an optical outcoupling layer of N,N′-Di-[(1-naphthyl)-N,N′-diphenyl]-(1,1′-biphenyl)-4,4′-diamine (α-NPD) is deposited on the anode.
New mechanism of runaway electron diffusion due to microturbulence in tokamaks
Authors: Abdullaev S. S. , Finken K. H. , Forster M.
Published: July 2012

Chaotic transport of runaway electrons in a toroidal system in the presence of a weak small-scale magnetic turbulent field with a wide mode spectrum is studied. Using a fast running mapping, the radial profiles of turbulent diffusion coefficients are calculated. It is found that at large Kubo numbers the chaotic transport of the electrons is described by a fractal-like radial dependence of the diffusion coefficients with reduced or zero values near low-order rational drift surfaces which form transport barriers. The latter can be one of the main reasons of the improved confinement of runaway electrons in tokamaks. One can expect that this effect may lead to the formation of the nested beams of runaway electrons.
Simulation studies for operating electron beam ion trap at very low energy for disentangling edge plasma spectra
Authors: Jin Xuelong , Fei Zejie , Xiao Jun , Lu Di , Hutton Roger , Zou Yaming
Published: July 2012

Electron beam ion traps (EBITs) are very useful tools for disentanglement studies of atomic processes in plasmas. In order to assist studies on edge plasma spectroscopic diagnostics, a very low energy EBIT, SH-PermEBIT, has been set up at the Shanghai EBIT lab. In this work, simulation studies for factors which hinder an EBIT to operate at very low electron energies were made based on the Tricomp (Field Precision) codes. Longitudinal, transversal, and total kinetic energy distributions were analyzed for all the electron trajectories. Influences from the electron current and electron energy on the energy depression caused by the space charge are discussed. The simulation results show that although the energy depression is most serious along the center of the electron beam, the electrons in the outer part of the beam are more likely to be lost when an EBIT is running at very low energy. Using the simulation results to guide us, we successfully managed to reach the minimum electron beam energy of 60 eV with a beam transmission above 57% for the SH-PermEBIT. Ar and W spectra were measured from the SH-PermEBIT at the apparent electron beam energies (read from the voltage difference between the electron gun cathode and the central drift tube) of 60 eV and 1200 eV, respectively. The spectra are shown in this paper.
Possible origins of a time-resolved frequency shift in Raman plasma amplifiers
Authors: Turnbull D. , Li S. , Morozov A. , Suckewer S.
Published: July 2012

Raman amplification is a resonant process in which the energy of a long pump pulse is transferred to a short seed pulse by a plasma wave. There has been a significant effort to identify a window in parameter space within which the interaction is expected to be highly efficient and not degraded by competing instabilities or excessive damping. However, experimental results have thus far failed to approach the theoretical limits. Recent amplified signal spectra display a characteristic blue shift, which evolves within the seed pulse duration and suggests that the mechanism responsible for this shift is also limiting amplification in these experiments. We present the evidence and explore different hypotheses for the origins of the shift—namely localization in density minima along the axis of laser propagation induced by an ion acoustic wave that could arise from the Langmuir decay instability, filamentation which could also modulate the plasma density but in the plane transverse to laser propagation, particle trapping, and additional ionization induced by the amplified seed field.
Stabilization of tearing modes by oscillating the resonant surface
Authors: Yang Xiaoqing , Wang Shaojie , Yang Weihong
Published: July 2012

The effects of the plasma current modulation on the linear instability of the tearing mode are numerically investigated. It is found that the tearing mode can be stabilized if the frequency of the modulation is suitable and the oscillation amplitude of the resonant surface position is large enough. The power needed for the lower-hybrid-current-drive to stabilize the tearing mode by oscillating the position of the resonant surface is comparable to the power consumption of the conventional method of tearing mode stabilization by using the electron-cyclotron-current-drive.
Variation in reproduction of a temperate deer, the southern pudu (Pudu puda)
Authors: Vidal Fernando , Smith-Flueck Jo Anne M. , Flueck Werner T. , Bartoš Luděk
Published: July 2012

Pudu (Pudu puda), occurring in the southern cone of Latin America, has been classified as vulnerable by the International Union for Conservation of Nature (IUCN), yet little is known about this animal in the wild, with most knowledge on the breeding behaviour coming from captive animals. For this second-smallest deer in the world, delayed implantation has been suggested to explain the two peaks in the annual cycle of male sexual hormones on the basis of the accepted tenet that the breeding period occurs only once a year, between March and June. However, in the present study, birth dates from fawns born at the Los Canelos semi-captive breeding centre in Chile and male courting behaviour revealed the possibility of two rutting periods: autumn and spring. To our knowledge, this is the first time that late-fall births (May through early June for 17% of fawns in the study population) have been recorded for the southern pudu; two of these four births were conceived by females in the wild. From zoo and captive-animal birth records (n = 97), only three fawns were born in the fall. For all births combined (n = 121), 77% occurred in spring. The roe deer (Capreolus capreolus) and Pere David deer (Elaphurus davidianus) have been considered the only two temperate cervids in which sexual activity is initiated by increasing daylength and which breed in early summer. Yet, the present results indicate a similar response from the southern pudu when under a wild or semi-captive environment, with breeding taking place in spring. These results suggest that this species may either have two reproductive periods per year or retains the capacity to be a breeder for a much more extended period of time than documented by earlier studies. Pudu, like other temperate deer, is responsive to photoperiod for timing its breeding period, but may further optimise its production of offspring by also responding to other environmental cues such as seasonal variation in food supply when climatic conditions are favourable.
The Chodura sheath for angles of a few degrees between the magnetic field and the surface of divertor targets and limiters
Authors: Stangeby P.C.
Published: July 2012

To achieve low deposited power flux density to solid surfaces in magnetic fusion devices, very small values of α are required, where α is the angle between
B
and the surface tangent. For an oblique magnetic field, there exists in front of the solid surface a Chodura sheath (CS) (also known as the ‘magnetic pre-sheath’) of thickness several ρ
i, the ion Larmor radius. The standard assumption is that the CS is additional to the Debye sheath (DS) of thickness several λ
D, the Debye length. Simple fluid modelling for collisionless CS conditions gives the drop in normalized electrostatic potential across the CS as eΔφ
CS/kT
e = ln(sin α). For an electrically floating wall there is the separate constraint of ambipolar flow to the wall eΔφ
floating/kT
e = 0.5 ln[(2π
m
e/m
i)(1 + T
i/T
e)], where Δφ
floating = Δφ
CS + Δφ
DS. For the case of a deuterium plasma and T
i = T
e, |eΔφ
floating/kT
e| = 2.84. For α < 3.35°, |eΔφ
CS/kT
e| exceeds 2.84 which evidently implies that the DS ceases to exist for such values of α and the entire potential drop would then occur across the CS. New analysis of the CS provides solutions for a number of quantities of practical importance, which improve on the solutions presently in use in models and edge impurity codes. Compared with the latter, the results of the present analysis indicate that (i) the E-field directed towards the solid surface is stronger and (ii) the plasma density drops more rapidly approaching the solid surface. The effect of (i) is to increase the probability of prompt local deposition of sputtered particles, while (ii) has the opposite effect.
Stability of pulse solutions for the discrete FitzHugh–Nagumo system
Authors: Hupkes H. , Sandstede B.
Published: July 2012

We show that the fast travelling pulses of the discrete FitzHugh–Nagumo system in the weak-recovery regime are nonlinearly stable. The spectral conditions that need to be verified involve linear operators that are associated to functional differential equations of mixed type. Such equations are ill-posed and do not admit a semi-flow, which precludes the use of standard Evans-function techniques. Instead, we construct the potential eigenfunctions directly by using exponential dichotomies, Fredholm techniques and an infinite-dimensional version of the Exchange Lemma.
MSeasy: unsupervised and untargeted GC-MS data processing
Authors: Nicolè Florence , Guitton Yann , Courtois Elodie A. , Moja Sandrine , Legendre Laurent , Hossaert-McKey Martine
Published: July 2012

Summary:  MSeasy performs unsupervised data mining on gas chromatography–mass spectrometry data. It detects putative compounds within complex metabolic mixtures through the clustering of mass spectra. Retention times or retention indices are used after clustering, together with other validation criteria, for quality control of putative compounds. The package generates a fingerprinting or profiling matrix compatible with NIST mass spectral search program and ARISTO webtool (Automatic Reduction of Ion Spectra To Ontology) for molecule identification. Most commonly used file formats, NetCDF, mzXML and ASCII, are acceptable. A graphical and user-friendly interface, MSeasyTkGUI, is available for R novices.

Availability:  MSeasy and MSeasytkGUI are implemented as R packages available at http://cran.r-project.org/web/packages/MSeasy/index.html and http://cran.r-project.org/web/packages/MSeasyTkGUI/index.html

Contact:  florence.nicole@univ-st-etienne.fr

Supplementary information: Additional information, self-guided tutorials and demonstration data are available on the web site: http://sites.google.com/site/rpackagemseasy/home. Workflow of MSeasy is available in supplementary material
Efficient sampling for Bayesian inference of conjunctive Bayesian networks
Authors: Sakoparnig Thomas , Beerenwinkel Niko
Published: July 2012

Motivation: Cancer development is driven by the accumulation of advantageous mutations and subsequent clonal expansion of cells harbouring these mutations, but the order in which mutations occur remains poorly understood. Advances in genome sequencing and the soon-arriving flood of cancer genome data produced by large cancer sequencing consortia hold the promise to elucidate cancer progression. However, new computational methods are needed to analyse these large datasets.

Results: We present a Bayesian inference scheme for Conjunctive Bayesian Networks, a probabilistic graphical model in which mutations accumulate according to partial order constraints and cancer genotypes are observed subject to measurement noise. We develop an efficient MCMC sampling scheme specifically designed to overcome local optima induced by dependency structures. We demonstrate the performance advantage of our sampler over traditional approaches on simulated data and show the advantages of adopting a Bayesian perspective when reanalyzing cancer datasets and comparing our results to previous maximum-likelihood-based approaches.

Availability: An R package including the sampler and examples is available at http://www.cbg.ethz.ch/software/bayes-cbn.

Contacts:  niko.beerenwinkel@bsse.ethz.ch
dbSNO: a database of cysteine S-nitrosylation
Authors: Lee Tzong-Yi , Chen Yi-Ju , Lu Cheng-Tsung , Ching Wei-Chieh , Teng Yu-Chuan , Huang Hsien-Da , Chen Yu-Ju
Published: July 2012

Summary:  S-nitrosylation (SNO), a selective and reversible protein post-translational modification that involves the covalent attachment of nitric oxide (NO) to the sulfur atom of cysteine, critically regulates protein activity, localization and stability. Due to its importance in regulating protein functions and cell signaling, a mass spectrometry-based proteomics method rapidly evolved to increase the dataset of experimentally determined SNO sites. However, there is currently no database dedicated to the integration of all experimentally verified S-nitrosylation sites with their structural or functional information. Thus, the dbSNO database is created to integrate all available datasets and to provide their structural analysis. Up to April 15, 2012, the dbSNO has manually accumulated >3000 experimentally verified S-nitrosylated peptides from 219 research articles using a text mining approach. To solve the heterogeneity among the data collected from different sources, the sequence identity of these reported S-nitrosylated peptides are mapped to the UniProtKB protein entries. To delineate the structural correlation and consensus motif of these SNO sites, the dbSNO database also provides structural and functional analyses, including the motifs of substrate sites, solvent accessibility, protein secondary and tertiary structures, protein domains and gene ontology.

Availability: The dbSNO is now freely accessible via http://dbSNO.mbc.nctu.edu.tw. The database content is regularly updated upon collecting new data obtained from continuously surveying research articles.

Contacts:  francis@saturn.yu.edu.tw or yujuchen@gate.sinica.edu.tw

Supplementary Information:  Supplementary data are available at Bioinformatics online.
Relationship of serum sodium concentration to mortality in a wide spectrum of heart failure patients with preserved and with reduced ejection fraction: an individual patient data meta‐analysis†
Authors: Rusinaru Dan , Tribouilloy Christophe , Berry Colin , Richards A. Mark , Whalley Gillian A. , Earle Nikki , Poppe Katrina K. , Guazzi Marco , Macin Stella M. , Komajda Michel , Doughty Robert N. ,   on behalf of the MAGGIC Investigators
Published: July 2012

Aims

Hyponatraemia has been associated with reduced survival in patients with heart failure and reduced ejection fraction (HF‐REF). The relationship between serum sodium and outcome is unclear in heart failure with preserved (≥50%) ejection fraction (HF‐PEF). Therefore, we used a large individual patient data meta‐analysis to study the risk of death associated with hyponatraemia in HF‐REF and in HF‐PEF.

Methods and results

This analysis included 14 766 patients from 22 studies that recruited patients without ejection fraction inclusion criterion at baseline and reported death from any cause. Cox proportional analysis was undertaken for hyponatraemia (sodium <135 mmol/L), adjusted for variables of clinical relevance, and stratified by study. The endpoint was death from any cause at 3 years. Patients with hyponatraemia (n = 1618) and patients with normal serum sodium had similar characteristics as regards to age, gender, and ischaemic aetiology. However, patients with hyponatraemia had higher New York Heart Association class and lower blood pressure. At follow‐up, there were 335 deaths among 1618 patients with hyponatraemia (21%) and 2128 deaths among 13 148 patients with normal serum sodium (16%). The risk of death appeared to increase linearly with serum sodium levels <140 mmol/L. Hyponatraemia was identified in 1199 HF‐REF patients (11%) and 419 HF‐PEF patients (11%). Hyponatraemia was independently predictive of death in both HF‐REF [adjusted hazard ratio (HR) 1.69, 95% confidence interval (CI) 1.50–1.91] and HF‐PEF (adjusted HR 1.40, 95% CI 1.10–1.79, P for interaction 0.20).

Conclusion

Hyponatraemia is a powerful determinant of mortality in patients with HF regardless of ejection fraction. Further work is needed to determine if correction of hyponatraemia translates into clinical benefit.