bluuebunny/crossref_metadata_2025 huggingface dataset:
The magnetic structure of exchange coupled FePt/FePt3 thin films
Authors: Couet S. , Demeter J. , Menéndez E. , Rüffer R. , Kinane C. J. , Laenens B. , Teichert A. , Tripathi S. , Almeida F. , Vantomme A. , Temst K.
Published: January 2013

We present a study of the magnetic structure of an exchange biased FePt/FePt3 bilayer system. By combining nuclear resonant scattering and polarized neutron reflectometry on the same sample, we are able to assess the magnetic ground state of both the ferromagnetic (F) FePt and antiferromagnetic (AF) FePt3 components of the system. Below the Néel temperature TN, AF order appears in the FePt3 layer with a spin wavevector pointing along the [100] axis. The AF Q1 phase, where the spin wavevector aligns along the [110] axis is not observed. A net magnetization of the FePt3 layer, which increases towards the FePt/FePt3 interface, is found. Magnetic coupling between the ferromagnetic moments within the FePt3 layer and the adjacent FePt layer is believed to be the cause of the suppression of the Q1 phase.
Development of the sputtering yields of ArF photoresist after the onset of argon ion bombardment
Authors: Takeuchi Takuya , Corbella Carles , Grosse-Kreul Simon , von Keudell Achim , Ishikawa Kenji , Kondo Hiroki , Takeda Keigo , Sekine Makoto , Hori Masaru
Published: January 2013

Modification of an advanced ArF excimer lithographic photoresist by 400 eV Ar ion irradiation was observed in situ in real time using both infrared spectroscopy and a quartz microbalance sensor. The photoresist sputtering yields had a characteristic behavior; the sputtering yields were higher than unity at the beginning, until an ion dose of 2 × 1016 ions cm−2. Thereafter, the yields decreased immediately to almost zero and remained constant with the yield at zero until a dose of approximately 4 × 1016 ions cm−2 was reached. At larger doses, the yields increased again and reached a steady-state value of approximately 0.6. This development of the sputtering yield after the onset of ion bombardment is explained by an ion-induced modification of the photoresist that includes preferential sputtering of individual groups, argon ion implantation and the generation of voids. All these effects must be taken into account to assess line-edge-roughness on a photoresist subjected to highly energetic ion irradiation.
Linear scaling explicitly correlated MP2-F12 and ONIOM methods for the long-range interactions of the nanoscale clusters in methanol aqueous solutions
Authors: Li Wei
Published: January 2013

A linear scaling quantum chemistry method, generalized energy-based fragmentation (GEBF) approach has been extended to the explicitly correlated second-order Møller-Plesset perturbation theory F12 (MP2-F12) method and own N-layer integrated molecular orbital molecular mechanics (ONIOM) method, in which GEBF-MP2-F12, GEBF-MP2, and conventional density functional tight-binding methods could be used for different layers. Then the long-range interactions in dilute methanol aqueous solutions are studied by computing the binding energies between methanol molecule and water molecules in gas-phase and condensed phase methanol-water clusters with various sizes, which were taken from classic molecular dynamics (MD) snapshots. By comparing with the results of force field methods, including SPC, TIP3P, PCFF, and AMOEBA09, the GEBF-MP2-F12 and GEBF-ONIOM methods are shown to be powerful and efficient for studying the long-range interactions at a high level. With the GEBF-ONIOM(MP2-F12:MP2) and GEBF-ONIOM(MP2-F12:MP2:cDFTB) methods, the diameters of the largest nanoscale clusters under studies are about 2.4 nm (747 atoms and 10 209 basis functions with aug-cc-pVDZ basis set) and 4 nm (3351 atoms), respectively, which are almost impossible to be treated by conventional MP2 or MP2-F12 method. Thus, the GEBF-F12 and GEBF-ONIOM methods are expected to be a practical tool for studying the nanoscale clusters in condensed phase, providing an alternative benchmark for ab initio and density functional theory studies, and developing new force fields by combining with classic MD simulations.
The multigrid POTFIT (MGPF) method: Grid representations of potentials for quantum dynamics of large systems
Authors: Peláez Daniel , Meyer Hans-Dieter
Published: January 2013

In this article, a new method, multigrid POTFIT (MGPF), is presented. MGPF is a grid-based algorithm which transforms a general potential energy surface into product form, that is, a sum of products of one-dimensional functions. This form is necessary to profit from the computationally advantageous multiconfiguration time-dependent Hartree method for quantum dynamics. MGPF circumvents the dimensionality related issues present in POTFIT [A. Jäckle and H.-D. Meyer, J. Chem. Phys. 104, 7974 (1996)10.1063/1.471513], allowing quantum dynamical studies of systems up to about 12 dimensions. MGPF requires the definition of a fine grid and a coarse grid, the latter being a subset of the former. The MGPF approximation relies on a series of underlying POTFIT calculations on grids which are smaller than the fine one and larger than or equal to the coarse one. This aspect makes MGPF a bit less accurate than POTFIT but orders of magnitude faster and orders of magnitude less memory demanding than POTFIT. Moreover, like POTFIT, MGPF is variational and provides an efficient error control.
Developing the model of laser ablation by considering the interplay between emission and expansion of aluminum plasma
Authors: Rezaei F. , Tavassoli S. H.
Published: January 2013

In the present study, the ablation behavior of aluminum target and its plasma radiation in noble ambient gases by a laser pulse with wavelength of 266 nm and pulse duration of 10 ns are numerically studied. A thermal model of laser ablation considering heat conduction, Euler equations, Saha-Eggert equations, Knudsen layer, mass and energy balance relations and optical shielding effects are used for calculation of plasma parameters. Effects of excitation energy on plasma expansion and its emissivity are investigated. Time and spatial-resolved plasma emission including bremsstrahlung, recombination and spectral emission at early delay times after laser irradiation is obtained. Effects of two ambient gases (He and Ar) as well as different gas pressures of 100, 300, 500, and 760 Torr on plasma expansion and its spectrum are studied. Results illustrate that at initial delay times, especially at high noble gas pressures, ionic lines have the maximum intensities, while at later times neutral lines dominate. When the pressure of ambient gas increases, a confinement of the plasma plume is predicted and the intensity of neutral lines decreases. Continuous emission increases with wavelength in both ambient gases. Spatially resolved analysis shows that an intense continuous emission is predicted next to the sample surface decreasing with distance from the latter.
Time fractional Schrödinger equation: Fox's H-functions and the effective potential
Authors: Bayın Selçuk Ş.
Published: January 2013

After introducing the formalism of the general space and time fractional Schrödinger equation, we concentrate on the time fractional Schrödinger equation and present new results via the elegant language of Fox's H-functions. We show that the general time dependent part of the wave function for the separable solutions of the time-fractional Schrödinger equation is the Mittag-Leffler function with an imaginary argument by two different methods. After separating the Mittag-Leffler function into its real and imaginary parts, in contrast to existing works, we show that the total probability is ⩽1 and decays with time. Introducing the effective potential approach, we also write the Mittag-Leffler function with an imaginary argument as the product of its purely decaying and purely oscillating parts. In the light of these, we reconsider the simple box problem.
High throughput physical vapour deposition and dielectric and ferroelectric screening of (Bi,Na)TiO3 thin-film libraries
Authors: Darby Mark S. B. , Guerin Samuel , Hayden Brian E. , Schreiner Hans-Jürgen , Yakovlev Sergey
Published: January 2013

Polycrystalline thin-film libraries of Bi2O3-TiO2-Na2O system have been synthesised over a wide composition region using elemental molecular beam epitaxy sources combined with an oxygen plasma source. Structural characterisation and the screening of both dielectric and ferroelectric properties of fabricated compounds have been carried out. The bismuth sodium titanate perovskite-type phases exhibited a high relative permittivity (up to 375), a loss tangent lower than 0.02 and ferroelectric properties superior to thin films synthesised using other deposition methods: a remnant polarization, Pr, approximately 22 μC/cm2 was observed in the optimal composition range. The high throughput approach allowed us to establish clearly the compositional boundaries of the ferroelectric perovskite phase in the system.
Surface loss probability of H radicals on silicon thin films in SiH4/H2 plasma
Authors: Abe Yusuke , Fukushima Atsushi , Takeda Keigo , Kondo Hiroki , Ishikawa Kenji , Sekine Makoto , Hori Masaru
Published: January 2013

The surface loss probability of H radicals was investigated in SiH4/H2 plasma using vacuum ultraviolet resonance absorption spectroscopy. The surface loss probability was calculated from the decay curve of the H radical density in the plasma afterglow and increased with the SiH4 flow rate. Silicon thin films deposited on the chamber wall were analyzed to investigate the relation between the surface loss probability and the surface condition. The surface reaction of H radicals is influenced by deposition precursors, such as SiH3 radicals. The density of H radicals significantly decreased with heating of the chamber wall up to 473 K. The surface loss probability of H radicals was estimated to be ca. 1 at 473 K. Quantitative measurements of the surface loss probability of H radicals in SiH4/H2 plasma are expected to be particularly important for understanding the surface reactions that occur during the deposition of silicon thin films.
Efficient and stable proton acceleration by irradiating a two-layer target with a linearly polarized laser pulse
Authors: Wang H. Y. , Yan X. Q. , Chen J. E. , He X. T. , Ma W. J. , Bin J. H. , Schreiber J. , Tajima T. , Habs D.
Published: January 2013

We report an efficient and stable scheme to generate ∼200 MeV proton bunch by irradiating a two-layer targets (near-critical density layer+solid density layer with heavy ions and protons) with a linearly polarized Gaussian pulse at intensity of 6.0×1020 W/cm2. Due to self-focusing of laser and directly accelerated electrons in the near-critical density layer, the proton energy is enhanced by a factor of 3 compared to single-layer solid targets. The energy spread of proton is also remarkably reduced. Such scheme is attractive for applications relevant to tumor therapy.
Carbon dioxide activation and dissociation on ceria (110): A density functional theory study
Authors: Cheng Zhuo , Sherman Brent J. , Lo Cynthia S.
Published: January 2013

Ceria (CeO2) is a promising catalyst for the reduction of carbon dioxide (CO2) to liquid fuels and commodity chemicals, in part because of its high oxygen storage capacity, yet the fundamentals of CO2 adsorption, activation, and reduction on ceria surfaces remain largely unknown. We use density functional theory, corrected for onsite Coulombic interactions (GGA+U), to explore various adsorption sites and configurations for CO2 on stoichiometric and reduced ceria (110), the latter with either an in-plane oxygen vacancy or a split oxygen vacancy. We find that CO2 adsorption on both reduced ceria (110) surfaces is thermodynamically favored over the corresponding adsorption on stoichiometric ceria (110), but the most stable adsorption configuration consists of CO2 adsorbed parallel to the reduced ceria (110) surface at a split oxygen vacancy. Structural changes in the CO2 molecule are also observed upon adsorption. At the split vacancy, the molecule bends out of plane to form a unidentate carbonate with the remaining oxygen anion at the surface; this is in stark contrast to the bridged carbonate observed for CO2 adsorption at the in-plane vacancy. Also, we analyze the pathways for CO2 conversion to CO on reduced ceria (110). The subtle difference in the energies of activation for the elementary steps suggest that CO2 dissociation is favored on the split vacancy, while the reverse process of CO oxidation may favor the formation of the in-plane vacancy. We thus show how the structure and properties of the ceria catalyst govern the mechanism of CO2 activation and reduction.
Species separation in inertial confinement fusion fuels
Authors: Bellei C. , Amendt P. A. , Wilks S. C. , Haines M. G. , Casey D. T. , Li C. K. , Petrasso R. , Welch D. R.
Published: January 2013

It is shown by means of multi-fluid particle-in-cell simulations that convergence of the spherical shock wave that propagates through the inner gas of inertial confinement fusion-relevant experiments is accompanied by a separation of deuterium (D) and tritium (T) ions across the shock front. Deuterons run ahead of the tritons due to their lower mass and higher charge-to-mass ratio and can reach the center several tens of picoseconds before the tritons. The rising edge of the DD and TT fusion rate is also temporally separated by the same amount, which should be an observable in experiments and would be a direct proof of the “stratification conjecture” on the shock front [Amendt et al., Phys. Plasmas 18, 056308 (2011)]. Moreover, dephasing of the D and T shock components in terms of density and temperature leads to a degradation of the DT fusion yield as the converging shock first rebounds from the fuel center (shock yield). For the parameters of this study, the second peak in the fusion yield (compression yield) is strongly dependent on the choice of the flux limiter.
Effects of molecular model, ionic strength, divalent ions, and hydrophobic interaction on human neurofilament conformation
Authors: Lee Joonseong , Kim Seonghoon , Chang Rakwoo , Jayanthi Lakshmi , Gebremichael Yeshitila
Published: January 2013

The present study examines the effects of the model dependence, ionic strength, divalent ions, and hydrophobic interaction on the structural organization of the human neurofilament (NF) brush, using canonical ensemble Monte Carlo (MC) simulations of a coarse-grained model with the amino-acid resolution. The model simplifies the interactions between the NF core and the sidearm or between the sidearms by the sum of excluded volume, electrostatic, and hydrophobic interactions, where both monovalent salt ions and solvents are implicitly incorporated into the electrostatic interaction potential. Several important observations are made from the MC simulations of the coarse-grained model NF systems. First, the mean-field type description of monovalent salt ions works reasonably well in the NF system. Second, the manner by which the NF sidearms are arranged on the surface of the NF backbone core has little influence on the lateral extension of NF sidearms. Third, the lateral extension of the NF sidearms is highly affected by the ionic strength of the system: at low ionic strength, NF-M is most extended but at high ionic strength, NF-H is more stretched out because of the effective screening of the electrostatic interaction. Fourth, the presence of Ca2 + ions induces the attraction between negatively charged residues, which leads to the contraction of the overall NF extension. Finally, the introduction of hydrophobic interaction does not change the general structural organization of the NF sidearms except that the overall extension is contracted.
Simulation of translational dielectrophoretic velocity spectra of erythrocytes in traveling electric field using various volume models
Authors: Bunthawin Sakshin , Ritchie Raymond J.
Published: January 2013

Proper models of cell geometry are needed for biophysical analysis of cellular electrical phenomena. This work compares various mathematical volume-models for normal human erythrocytes (discocyte) possessing biconcave-discoid form to simulate translational dielectrophoretic velocity spectra of erythrocyte suspensions induced in a traveling electric field over a frequency range from 1 kHz to 15 MHz. The non-spherical volumes of the oblate-spheroid, the prolate-spheroid, and the oval of Cassini and the “Bun-model” were numerically evaluated according to the normal range of cellular dimension values for mammalian erythrocytes. The latter model is the novel approach derived to provide a more realistic model for the shape of discocytes in the thin biconcave-disc form with a toroidal rim. The bun model is also more rugged than the Cassini equation. Using the actual cell dimensions for calculations, the numerical results among these calculated cell volumes revealed large and significant differences with respect to the Bun-model of +32.09%, +8.95%, and −8.45% for prolate-spheroid, Cassini's equation, and oblate-spheroid, respectively. These large volume deviations shift the magnitude of the sharp peak in dielectrophoretic velocity spectra to lower values with differences of +189.28%, +7.66%, and −9.49%, respectively. For traveling wave dielectrophoresis, similar results were found for the sharp peak of +145.76%, +7.71%, and −9.50%, respectively. The suitability of the Bun-model was verified by curve-fitting of the cell velocity spectra between experimental and theoretical curves, which gave the maximum discrepancies of less than ±10%.
Hamiltonian integrability of two-component short pulse equations
Authors: Brunelli J. C. , Sakovich S.
Published: January 2013

We obtain the bi-Hamiltonian structure for some of the two-component short pulse equations proposed in the literature to generalize the original short pulse equation when polarized pulses propagate in anisotropic media.
Quantitative understanding of the benefit of selective emitters on screen printed Si solar cells as a function of improved paste contact properties
Authors: Renshaw J. S. , Cooper I. B. , Rohatgi A.
Published: January 2013

We propose using an effective Schottky barrier height determined from experimental data to approximate the contact resistance of Si solar cells. This model is used to explore the efficiency benefit that selective emitter (SE) solar cells provide over a homogeneous emitter (HE). Our simulations show that as paste technology improves, the selective emitter-induced efficiency benefit for the devices modeled in this study is reduced from a maximum of 0.43% absolute at a barrier height of 2.5 eV to basically no advantage at 1 eV. This technique can also be used in the optimization of homogeneous emitter solar cells, so that contact resistance may be considered in a dynamic way as emitter profiles are varied.
Investigation of an anomalous hump in gate current after negative-bias temperature-instability in HfO2/metal gate p-channel metal-oxide-semiconductor field-effect transistors
Authors: Ho Szu-Han , Chang Ting-Chang , Wu Chi-Wei , Lo Wen-Hung , Chen Ching-En , Tsai Jyun-Yu , Liu Guan-Ru , Chen Hua-Mao , Lu Ying-Shin , Wang Bin-Wei , Tseng Tseung-Yuen , Cheng Osbert , Huang Cheng-Tung , Sze Simon M.
Published: January 2013

This Letter investigates a hump in gate current after negative-bias temperature-instability (NBTI) in HfO2/metal gate p-channel metal-oxide-semiconductor field-effect transistors. Measuring gate current at initial through body floating and source/drain floating shows that hole current flows from source/drain. The fitting of gate current (Ig)-gate voltage (Vg) characteristic curves demonstrates that the Frenkel-Poole mechanism dominates the conduction. Next, by fitting the gate current after NBTI, in the order of Frenkel-Poole then tunneling, the Frenkel-Poole mechanism can be confirmed. These phenomena can be attributed to hole trapping in high-k bulk and the electric field formula Ehigh-k εhigh-k = Q + Esio2εsio2.
Low temperature resistivity, thermoelectricity, and power factor of Nb doped anatase TiO2
Authors: Jaćimović J. , Gaál R. , Magrez A. , Piatek J. , Forró L. , Nakao S. , Hirose Y. , Hasegawa T.
Published: January 2013

The resistivity of a very high quality anatase TiO2 doped with 6% of Nb was measured from 300 K down to 40 mK. No sign of superconductivity was detected. Instead, a minute quantity of cation vacancies resulted in a Kondo scattering. Measurements of thermo-electric power and resistivity were extended up to 600 K. The calculated power factor has a peak value of 14 μW/(K2cm) at 350 K, which is comparable to that of Bi2Te3 [Venkatasubramanian et al., Nature 413, 597 (2001)], the archetype thermolectrics. Taking the literature value for the thermal conductivity of Nb doped TiO2 thin films, the calculated figure of merit (ZT) is in the range of 0.1 above 300 K. This value is encouraging for further engineering of the material in order to reach ZT of 1 suitable for high temperature thermoelectrics.
Enhanced performance of GaN based light-emitting diodes with a low temperature p-GaN hole injection layer
Authors: Li Hongjian , Kang Junjie , Li Panpan , Ma Jun , Wang Hui , Liang Meng , Li Zhicong , Li Jing , Yi Xiaoyan , Wang Guohong
Published: January 2013

A hole injection layer (HIL) is designed in GaN-based light emitting diodes (LEDs) between multiple quantum wells and p-AlGaN electron blocking layer (EBL). Based on numerical simulation by apsys, the band diagram is adjusted by HIL, leading to the improved hole-injection efficiency. The designed HIL is a p-GaN buffer layer grown at low temperature (LT_pGaN) on last quantum barrier before p-AlGaN EBL. The output power of the fabricated GaN-based LED device with LT_pGaN HIL is enhanced by 128% at 100 A/cm2, while the efficiency droop is reduced by 33% compared to the conventional LED.
Influence of chaotic synchronization on mixing in the phase space of interacting systems
Authors: Astakhov Sergey V. , Dvorak Anton , Anishchenko Vadim S.
Published: January 2013

Using the concept of the relative metric entropy, we study the influence of the synchronization phenomenon on mixing rate in the phase space of deterministic and noisy chaotic systems. We show that transition to both complete and phase synchronization of chaos is accompanied by the decrease of the level of mixing induced by internal nonlinear mechanisms of interacting systems as well as by external noise influence. Therefore, the decrease of the mixing rate in the phase space of interacting systems may indicate transition to synchronization. The obtained results are important for time series analysis in various types of real noisy systems (e.g., biological, social, and financial systems).
Comparison of non-neutral electron plasma confinement in harmonic and rectangular potentials in a very dense regime
Authors: Mohamed T. , Mohri A. , Yamazaki Y.
Published: January 2013

Confinement of high density electron plasmas in a strong uniform magnetic field was experimentally studied in a multi-ring trap (MRT). The trap was housed inside a bore tube and surrounded by a superconducting solenoid. A 5 T magnetic field was used to provide radial confinement while an electrostatic harmonic or rectangular potential well was used for axial confinement. For trapped electrons of N = 1.2 × 1010 in a harmonic potential well (HPW) with the trap length of LT = 320 mm, the plasma lifetime was about 104 s and it became much longer at lower N = 4.5 × 109. Such long holding times were achieved without application of rotating electric fields. Contrastingly, in a rectangular potential well (RPW), the plasma of N = 1.2 × 1010 under the same trap length expanded to cover the whole Faraday Cup within 200 s, where its radial expansion rate was η = 3.2 × 10−2 mm/s, which was 20 times faster than HPW. The lifetime for RPW became shorter with increasing LT and scaled as 1/[LT]2. This scaling found for high density plasmas is similar to the obtained one with different Penning–Malmberg traps at UC San Diego (USCD).
Cooperative accumulation of coherent undulator radiation emitted from periodic electron bunches
Authors: Seo Y. H.
Published: January 2013

Cavity build-up of coherent undulator synchrotron radiation emitted by periodic electron bunches is investigated. At the optimal off-grazing resonance, the bunch slippage relative to the radiation pulse introduces an initial transient period during which radiation accumulates cooperatively as if it is emitted by a single bunch. The power growth during the period is quadratic to the number of bunches. The number of cooperative bunches is ∼2 ℓs 2, where ℓs denotes the slippage length in units of the resonant wavelength.
Enhanced spin pumping damping in yttrium iron garnet/Pt bilayers
Authors: Rezende S. M. , Rodríguez-Suárez R. L. , Soares M. M. , Vilela-Leão L. H. , Ley Domínguez D. , Azevedo A.
Published: January 2013

Detailed measurements of the magnetic relaxation expressed in the linewidth of the ferromagnetic resonance (FMR) absorption in thick films of yttrium iron garnet (YIG) and in YIG/Pt bilayers carried out at room temperature reveal a very large increase in the relaxation rate with the deposition of a Pt layer. The additional relaxation increases linearly with the microwave frequency characteristics of the spin pumping mechanism. The value of the spin mixing conductance obtained from the data is one order of magnitude larger than the largest possible value determined from measurements of the voltage generated by FMR spin-pumping.
Insights into the regulation of the human COP9 signalosome catalytic subunit, CSN5/Jab1
Authors: Echalier Aude , Pan Yunbao , Birol Melissa , Tavernier Nicolas , Pintard Lionel , Hoh François , Ebel Christine , Galophe Nathalie , Claret François X. , Dumas Christian
Published: January 2013

The COP9 (Constitutive photomorphogenesis 9) signalosome (CSN), a large multiprotein complex that resembles the 19S lid of the 26S proteasome, plays a central role in the regulation of the E3-cullin RING ubiquitin ligases (CRLs). The catalytic activity of the CSN complex, carried by subunit 5 (CSN5/Jab1), resides in the deneddylation of the CRLs that is the hydrolysis of the cullin-neural precursor cell expressed developmentally downregulated gene 8 (Nedd8)isopeptide bond. Whereas CSN-dependent CSN5 displays isopeptidase activity, it is intrinsically inactive in other physiologically relevant forms. Here we analyze the crystal structure of CSN5 in its catalytically inactive form to illuminate the molecular basis for its activation state. We show that CSN5 presents a catalytic domain that brings essential elements to understand its activity control. Although the CSN5 active site is catalytically competent and compatible with di-isopeptide binding, the Ins-1 segment obstructs access to its substrate-binding site, and structural rearrangements are necessary for the Nedd8-binding pocket formation. Detailed study of CSN5 by molecular dynamics unveils signs of flexibility and plasticity of the Ins-1 segment. These analyses led to the identification of a molecular trigger implicated in the active/inactive switch that is sufficient to impose on CSN5 an active isopeptidase state. We show that a single mutation in the Ins-1 segment restores biologically relevant deneddylase activity. This study presents detailed insights into CSN5 regulation. Additionally, a dynamic monomer-dimer equilibrium exists both in vitro and in vivo and may be functionally relevant.
STAT3 suppresses transcription of proapoptotic genes in cancer cells with the involvement of its N-terminal domain
Authors: Timofeeva Olga A. , Tarasova Nadya I. , Zhang Xueping , Chasovskikh Sergey , Cheema Amrita K. , Wang Honghe , Brown Milton L. , Dritschilo Anatoly
Published: January 2013

Activation of STAT3 in cancers leads to gene expression promoting cell proliferation and resistance to apoptosis, as well as tumor angiogenesis, invasion, and migration. In the characterization of effects of ST3-H2A2, a selective inhibitor of the STAT3 N-terminal domain (ND), we observed that the compound induced apoptotic death in cancer cells associated with robust activation of proapoptotic genes. Using ChIP and tiling human promoter arrays, we found that activation of gene expression in response to ST3-H2A2 is accompanied by altered STAT3 chromatin binding. Using inhibitors of STAT3 phosphorylation and a dominant-negative STAT3 mutant, we found that the unphosphorylated form of STAT3 binds to regulatory regions of proapoptotic genes and prevents their expression in tumor cells but not normal cells. siRNA knockdown confirmed the effects of ST3-HA2A on gene expression and chromatin binding to be STAT3 dependent. The STAT3-binding region of the C/EBP-homologous protein (CHOP) promoter was found to be localized in DNaseI hypersensitive site of chromatin in cancer cells but not in nontransformed cells, suggesting that STAT3 binding and suppressive action can be chromatin structure dependent. These data demonstrate a suppressive role for the STAT3 ND in the regulation of proapoptotic gene expression in cancer cells, providing further support for targeting STAT3 ND for cancer therapy.
Boronated tartrolon antibiotic produced by symbiotic cellulose-degrading bacteria in shipworm gills
Authors: Elshahawi Sherif I. , Trindade-Silva Amaro E. , Hanora Amro , Han Andrew W. , Flores Malem S. , Vizzoni Vinicius , Schrago Carlos G. , Soares Carlos A. , Concepcion Gisela P. , Distel Dan L. , Schmidt Eric W. , Haygood Margo G.
Published: January 2013

Shipworms are marine wood-boring bivalve mollusks (family Teredinidae) that harbor a community of closely related Gammaproteobacteria as intracellular endosymbionts in their gills. These symbionts have been proposed to assist the shipworm host in cellulose digestion and have been shown to play a role in nitrogen fixation. The genome of one strain of
Teredinibacter turnerae
, the first shipworm symbiont to be cultivated, was sequenced, revealing potential as a rich source of polyketides and nonribosomal peptides. Bioassay-guided fractionation led to the isolation and identification of two macrodioloide polyketides belonging to the tartrolon class. Both compounds were found to possess antibacterial properties, and the major compound was found to inhibit other shipworm symbiont strains and various pathogenic bacteria. The gene cluster responsible for the synthesis of these compounds was identified and characterized, and the ketosynthase domains were analyzed phylogenetically. Reverse-transcription PCR in addition to liquid chromatography and high-resolution mass spectrometry and tandem mass spectrometry revealed the transcription of these genes and the presence of the compounds in the shipworm, suggesting that the gene cluster is expressed in vivo and that the compounds may fulfill a specific function for the shipworm host. This study reports tartrolon polyketides from a shipworm symbiont and unveils the biosynthetic gene cluster of a member of this class of compounds, which might reveal the mechanism by which these bioactive metabolites are biosynthesized.
Emergency care and first aid for farm animals in the UK - Mini Review.
Authors: Duncanson G.
Published: January 2013

All members of the Royal College of Veterinary Surgeons are required to be able to provide emergency care, first aid and euthanasia for farm animals including poultry. They should be able to provide cardiopulmonary resuscitation. However, the very size of cattle makes the known principles difficult to put into practice. They have to make an assessment of pain and manage it. Farm animals are often violent and instant pain relief and sedation are required. Situations requiring first aid are fractures, ligament or tendon injuries, burns, acute metabolic disease and bloat. Practitioners require knowledge to deal with these emergencies.
Fish frauds: the DNA challenge.
Authors: Armani A. , Castigliego L. , Guidi A.
Published: January 2013

The rising demand for seafood and trade globalization has brought about a rapid increase in the number of fish species traded. Consequently, the occurrence of mislabelling is growing as well, reaching levels of concerns in USA, Canada and Europe. In this light, the evolving consciousness of consumers and the new exigencies of commerce call for greater safety and quality requirements. These factors have made urgent the need for efficient traceability systems, aimed to ensure transparency on the identity and origin of the traded products and the compliance with the regulations concerning illegal fisheries and labelling. Moreover, greater efforts are necessary to create a list of market names that can be recognized both locally and internationally, in order to overcome the confusion regarding fish denominations. In this context, molecular analysis represents the most promising challenge to verify and support traceability in the seafood chain. Nowadays, the three mitochondrial genes
cytb
,
COI
and
16srRNA
are the most targeted for this purpose and, among the available procedures, the DNA bar coding is the most commonly applied to verify the labelling compliances, also at the official level. In this review, the most important issues relating to these topics have been reported and discussed.
Mortality of American Bullfrog Tadpoles Lithobates catesbeianus Infected by Gyrodactylus jennyae and Experimentally Exposed to Batrachochytrium dendrobatidis
Authors: Paetow Linda J. , McLaughlin J. Daniel , Pauli Bruce D. , Marcogliese David J.
Published: January 2013

The fungal pathogen Batrachochytrium dendrobatidis (Bd), which causes the disease chytridiomycosis in postmetamorphic amphibians, has been linked to amphibian population declines. Different amphibian species, however, exhibit different susceptibility to Bd pathogenicity. At the same time, agricultural pesticides commonly found contaminating aquatic habitats have been reported to increase the susceptibility of amphibians to pathogens. To investigate whether certain pesticides are able to alter the pathogenicity of Bd to larval amphibians, we exposed larval American bullfrogs Lithobates catesbeianus to end-use formulations of the herbicides atrazine or glyphosate, and then exposed them to Bd. Following the experimental exposures, a preexisting infection of the tadpoles by the monogenean ectoparasite Gyrodactylus jennyae was detected in all experimental and control tadpoles. Gyrodactylus jennyae infection intensity varied, and individuals with heavy G. jennyae infections suffered more skin erosion due to grazing by the parasite. Tadpoles experimentally exposed to Bd, or to Bd and either herbicide, had significantly reduced survival rates compared with untreated tadpoles that were only infected by G. jennyae. Increased mortality was also correlated with degree of skin erosion; survival of tadpoles with severe skin erosion was significantly reduced compared with that of tadpoles with no, or mild, skin erosion. While infected with G. jennyae, the group of tadpoles with the lowest survival rate (exposed only to Bd) included significantly more individuals exhibiting severe skin erosion and significantly fewer individuals without skin erosion, compared with the control group. These results emphasize the potential pathogenicity of gyrodactylid infections in larval amphibian hosts and suggest that concomitant exposures to Bd may enhance infections and effects of G. jennyae in bullfrog tadpoles.

Received February 3, 2012; accepted August 10, 2012
Experimental Infection of Koi Carp with Viral Hemorrhagic Septicemia Virus Type IVb
Authors: Cornwell Emily R. , LaBuda Sandra L. , Groocock Geoffrey H. , Getchell Rodman G. , Bowser Paul R.
Published: January 2013

Viral hemorrhagic septicemia virus (VHSV) type IVb has a wide host range that includes at least three cyprinid species: Fathead Minnow Pimephales promelas, Emerald Shiner Notropis atherinoides, and Bluntnose Minnow P. notatus. To date, VHSV IVb has only been found in wild fish. However, the possibility of infection in culture facilities remains. Koi Carp Cyprinus carpio are a major ornamental aquaculture species in the United States; however, their potential to become infected with VHSV IVb has not yet been examined. In this study, we exposed Koi to 3 × 106 PFU VHSV Great Lakes isolate MI03 by intraperitoneal injection. While we observed low mortality (0–5%), VHSV was isolated in cell culture from the majority of fish up to 28 d postexposure (DPE) and was detected by a quantitative reverse transcription polymerase chain reaction (qRT-PCR) assay up to 90 DPE, when the trial was terminated. The results of this study strongly suggest that Koi are at risk for VHSV infection, although their susceptibility by intraperitoneal injection appears to be low. This study also provides more evidence of the sensitivity of qRT-PCR for detection of VHSV IVb.

Received May 9, 2012; accepted September 14, 2012
Experimental characterization and modelling of non-linear coupling of the lower hybrid current drive power on Tore Supra
Authors: Preynas M. , Goniche M. , Hillairet J. , Litaudon X. , Ekedahl A. , Colas L.
Published: January 2013

To achieve steady-state operation on future fusion devices, in particular on ITER, the coupling of the lower hybrid wave must be optimized on a wide range of edge conditions. However, under some specific conditions, deleterious effects on the lower hybrid current drive (LHCD) coupling are sometimes observed on Tore Supra. In this way, dedicated LHCD experiments have been performed using the LHCD system of Tore Supra, composed of two different conceptual designs of launcher: the fully active multi-junction (FAM) and the new passive active multi-junction (PAM) antennas. A non-linear interaction between the electron density and the electric field has been characterized in a thin plasma layer in front of the two LHCD antennas. The resulting dependence of the power reflection coefficient (RC) with the LHCD power is not predicted by the standard linear theory of the LH wave coupling. A theoretical model is suggested to describe the non-linear wave–plasma interaction induced by the ponderomotive effect and implemented in a new full wave LHCD code, PICCOLO-2D (ponderomotive effect in a coupling code of lower hybrid wave-2D). The code self-consistently treats the wave propagation in the antenna vicinity and its interaction with the local edge plasma density. The simulation reproduces very well the occurrence of a non-linear behaviour in the coupling observed in the LHCD experiments. The important differences and trends between the FAM and the PAM antennas, especially a larger increase in RC for the FAM, are also reproduced by the PICCOLO-2D simulation. The working hypothesis of the contribution of the ponderomotive effect in the non-linear observations of LHCD coupling is therefore validated through this comprehensive modelling for the first time on the FAM and PAM antennas on Tore Supra.
Surface modification of tungsten and tungsten–tantalum alloys exposed to high-flux deuterium plasma and its impact on deuterium retention
Authors: Zayachuk Y. , 't Hoen M.H.J. , Zeijlmans van Emmichoven P.A. , Terentyev D. , Uytdenhouwen I. , van Oost G.
Published: January 2013

Samples of tungsten and tungsten–tantalum alloy (with 5 mass per cent of Ta) were exposed to high-flux deuterium plasma at different fluences. The surface modification was studied with scanning electron microscopy, and deuterium retention was measured by thermal desorption spectroscopy (TDS). In the high fluence range of ∼3.5 × 1026–1027 m-2, multiple large-size blisters are formed on the W surface, while blisters on the W–Ta surface are considerably smaller in size and number. Deuterium retention in this fluence range was found to be systematically higher in W than in W–Ta. Correlation between the evolution of the blistering patterns and the TDS spectra as a function of fluence suggests that trapping in the sub-surface cavities associated with blisters is the predominant trapping mechanism in tungsten in the case of high fluence exposures. We attribute the lower retention in W–Ta under the investigated conditions to the weaker blistering.
The Nielsen realization problem for asymptotic Teichmüller modular groups
Authors: Fujikawa Ege , Matsuzaki Katsuhiko
Published: January 2013

Under a certain geometric assumption on a hyperbolic Riemann surface, we prove an asymptotic version of the fixed point theorem for the Teichmüller modular group, which asserts that every finite subgroup of the asymptotic Teichmüller modular group has a common fixed point in the asymptotic Teichmüller space. For its proof, we use a topological characterization of the asymptotically trivial mapping class group, which has been obtained in the authors’ previous paper, but a simpler argument is given here. As a consequence, every finite subgroup of the asymptotic Teichmüller modular group is realized as a group of quasiconformal automorphisms modulo coincidence near infinity. Furthermore, every finite subgroup of a certain geometric automorphism group of the asymptotic Teichmüller space is realized as an automorphism group of the Royden boundary of the Riemann surface. These results can be regarded as asymptotic versions of the Nielsen realization theorem.
On epsilon factors attached to supercuspidal representations of unramified 𝑈(2,1)
Authors: Miyauchi Michitaka
Published: January 2013

Let

G
G

be the unramified unitary group in three variables defined over a

p
p

-adic field

F
F

with

p
≠
2

p \neq 2

. Gelbart, Piatetski-Shapiro and Baruch attached zeta integrals of Rankin-Selberg type to irreducible generic representations of

G
G

. In this paper, we formulate a conjecture on

L
L

- and

ε
\varepsilon

-factors defined through zeta integrals in terms of newforms for

G
G

, which is an analogue of the result by Casselman and Deligne for

G
L

(
2
)

\mathrm {GL}(2)

. We prove our conjecture for the generic supercuspidal representations of

G
G

.
Context-specific repeatability of personality traits in a wild bird: a reaction-norm perspective
Authors: Kluen Edward , Brommer Jon E.
Published: January 2013

Animal personality is defined as behavior that is consistent across time and context. We here applied a reaction-norm perspective implemented as a random regression phenotypic model (RRPM) to behaviors measured on blue tits Cyanistes caeruleus. During 3 consecutive breeding and winter seasons (2007–2009), a total of 508 wild-caught blue tits were assayed in a standard, artificial setup (a bird cage) for 1) activity, 2) time to escape, and 3) neophobia-related behavior. Activity was found to be repeatable both within and across seasonal contexts, but escape time and neophobia-related behavior were repeatable only in winter. Our RRPM confirmed that this latter finding was due to crossing of the individual-specific reaction norms between the 2 seasonal contexts. Our work illustrates how a behavior measured in a standardized manner may or may not be repeatable across time within a context but not between contexts, depending on the interindividual variation in reaction-norm properties. Our findings suggest that research on animal behavior plasticity can benefit from taking onboard context-specific analyses in a more explicit manner than what is typically done.
Practical Inheritance
Authors: Sybert Virginia P.
Published: January 2013

Genetic disorders are unique among diseases in that they affect families and generations, not just individuals. In the diagnosis and discussion of an inherited disorder, the recurrence risk must always be included. Will it happen again? Who is at risk to inherit? What is the magnitude of that risk? How severely will the condition be manifested? The answers to these questions depend on the mode of inheritance and the penetrance and expression of the gene(s) for the disorder.
Disorders of Pigmentation
Authors: Sybert Virginia P.
Published: January 2013

Hyperpigmentation – Carney Complex – Dowling-Degos Disease – Dyskeratosis Congenita – Fanconi Anemia – Hemochromatosis – Incontinentia Pigmenti – LEOPARD Syndrome – Linear and Whorled Nevoid Hypermelanosis – McCune-Albright Syndrome – Naegeli Syndrome – Neurofibromatosis – Nevus Phakomatosis Pigmentovascularis – Peutz-Jeghers Syndrome – Universal Melanosis – Hypopigmentation – Albinisms – Albinism with Deafness – Hermansky-Pudlak Syndrome – Oculocutaneous Albinism Tyrosinase Negative – Oculocutaneous Albinism Tyrosinase Positive – Yellow Mutant Albinism – Cross Syndrome – Hypomelanosis of Ito – Piebaldism – Premature Canities – Vitiligo – Waardenburg Syndrome Types 1, 2, 3, and 4
Premature Aging
Authors: Sybert Virginia P.
Published: January 2013

Cockayne Syndrome – De Barsy Syndrome – Hallermann-Streiff Syndrome – Hutchinson-Gilford Progeria – Werner Syndrome
Photosensitivity
Authors: Sybert Virginia P.
Published: January 2013

Bloom Syndrome – Hartnup Disorder – Kindler Syndrome – Polymorphous Light Eruption – Rothmund-Thomson Syndrome – Xeroderma Pigmentosum
Professional skills and behaviour
Authors: Gardiner Matthew D. , Borley Neil R.
Published: January 2013

This chapter covers the following professional skills: good surgical practice, communication, judgement and decision-making, clinical governance and patient safety, audit, appraisal, and revalidation, consent and confidentiality, education, training, and research, child protection, and end-of-life care.
Emergency surgery
Authors: Gardiner Matthew D. , Borley Neil R.
Published: January 2013

This chapter begins by discussing the basic principles of Advanced Trauma Life Support, care of the critically ill surgical patient, shock, SIRS and sepsis, and blood products and transfusion, before focusing on the key areas of knowledge, namely traumatic head injury, spine and spinal cord trauma, maxillofacial trauma, cardiothoracic trauma, abdominal trauma, urological trauma, vascular trauma, assessment of the acute abdomen, acute appendicitis, acute upper gastrointestinal haemorrhage, lower gastrointestinal haemorrhage, gastrointestinal obstruction, gastrointestinal perforation, acute pancreatitis, and superficial sepsis. The chapter concludes with relevant case-based discussions.
Plastic and reconstructive surgery
Authors: Gardiner Matthew D. , Borley Neil R.
Published: January 2013

This chapter begins by discussing the basic principles of acute inflammation, cutaneous wound healing, and the reconstructive ladder, before focusing on the key areas of knowledge, namely congenital conditions, emergency management of burns, emergency hand surgery, tendon injuries, peripheral nerve injuries, elective hand surgery, cutaneous malignant melanoma, non-melanoma skin cancer, and benign skin lesions. The chapter concludes with relevant case-based discussions.
Human prion diseases
Authors: Will R G
Published: January 2013

Prion protein (for proteinacious infectious particle) is a membrane-associated glycoprotein present in all mammalian species. Its normal function is unknown, but in prion diseases (also known as transmissible spongiform encephalopathies) a post-translationally modified form of the protein, partially resistant to protease digestion, is deposited in the brain and associated—after long incubation periods—with neuronal dysfunction and death....
Spinal cord injury and its management
Authors: Barnes M P
Published: January 2013

Spinal cord injury most commonly affects young men as a consequence of road traffic accidents, violence, and sports injuries; falls are a common cause in older patients.

Appropriate management of the individual at the scene of an accident is vital to avoid unnecessary worsening of a spinal cord injury. Those who are unconscious should be assumed to have a cervical spine injury until proven otherwise, with (1) the head and neck held firmly (as far as possible) in a neutral position using (if available) a semi-rigid collar, and (2) transportation on a spinal board with a head immobilizer....
The motor neuron diseases
Authors: Brockington Alice , Shaw Pamela J.
Published: January 2013

Motor neuron diseases are a family of conditions that lead to selective loss of function of the lower and/or upper motor neurons controlling the voluntary muscles of the limbs or bulbar region. Precise diagnosis is essential for prognosis, identification of those diseases with genetic implications, and for (in a very few cases) specific treatment....
Metabolic and endocrine disorders
Authors: Hilton-Jones David , Edwards Richard
Published: January 2013

Abstracts and keywords to be supplied.