bluuebunny/crossref_metadata_2025 huggingface dataset:
Propane dehydrogenation over Pt–Cu bimetallic catalysts: the nature of coke deposition and the role of copper
Authors: Han Zhiping , Li Shuirong , Jiang Feng , Wang Tuo , Ma Xinbin , Gong Jinlong
Published: May 2014

This paper describes a promotional effect of Cu on the catalytic performance of Pt/Al2O3 catalysts for propane dehydrogenation. The Pt–Cu interaction inhibits propylene adsorption and suppresses C–C bond rupture, leading to the enhanced catalytic performance of the Pt–Cu/Al2O3 catalyst.
Temperature assisted acid catalyzed peptization of TiO2; facile sol–gel approach for thermally stable anatase phase
Authors: Kattoor Vidya , Smitha Venu Sreekala , Peer Mohamed A. , Saraswathy Hareesh Unnikrishnan Nair , Warrier Krishna Gopakumar
Published: May 2014

Temperature assisted, acid catalyzed peptization of aqueous sol–gel titania can yield phase pure anatase with enhanced photocatalytic activity and thermal stability up to 800 °C.
Skirting terahertz waves in a photo-excited nanoslit structure
Authors: Shalaby Mostafa , Fabiańska Justyna , Peccianti Marco , Ozturk Yavuz , Vidal Francois , Sigg Hans , Morandotti Roberto , Feurer Thomas
Published: May 2014

Terahertz fields can be dramatically enhanced as they propagate through nanometer-sized slits. The enhancement is mediated by a significant accumulation of the induced surface charges on the surrounding metal. This enhancement is shown here to be dynamically modulated while the nanoslits are gradually shunted using a copropagating optical beam. The terahertz fields are found to skirt the nanoscale photo-excited region underneath the slits, scattering to the far field and rigorously mapping the near field.
Hardness of FeB4: Density functional theory investigation
Authors: Zhang Miao , Lu Mingchun , Du Yonghui , Gao Lili , Lu Cheng , Liu Hanyu
Published: May 2014

A recent experimental study reported the successful synthesis of an orthorhombic FeB4 with a high hardness of 62(5) GPa [H. Gou et al., Phys. Rev. Lett. 111, 157002 (2013)], which has reignited extensive interests on whether transition-metal borides compounds will become superhard materials. However, it is contradicted with some theoretical studies suggesting transition-metal boron compounds are unlikely to become superhard materials. Here, we examined structural and electronic properties of FeB4 using density functional theory. The electronic calculations show the good metallicity and covalent Fe–B bonding. Meanwhile, we extensively investigated stress-strain relations of FeB4 under various tensile and shear loading directions. The calculated weakest tensile and shear stresses are 40 GPa and 25 GPa, respectively. Further simulations (e.g., electron localization function and bond length along the weakest loading direction) on FeB4 show the weak Fe–B bonding is responsible for this low hardness. Moreover, these results are consistent with the value of Vickers hardness (11.7–32.3 GPa) by employing different empirical hardness models and below the superhardness threshold of 40 GPa. Our current results suggest FeB4 is a hard material and unlikely to become superhard (>40 GPa).
Data fusion in X-ray computed tomography using a superiorization approach
Authors: Schrapp Michael J. , Herman Gabor T.
Published: May 2014

X-ray computed tomography (CT) is an important and widespread inspection technique in industrial non-destructive testing. However, large-sized and heavily absorbing objects cause artifacts due to either the lack of penetration of the specimen in specific directions or by having data from only a limited angular range of views. In such cases, valuable information about the specimen is not revealed by the CT measurements alone. Further imaging modalities, such as optical scanning and ultrasonic testing, are able to provide data (such as an edge map) that are complementary to the CT acquisition. In this paper, a superiorization approach (a newly developed method for constrained optimization) is used to incorporate the complementary data into the CT reconstruction; this allows precise localization of edges that are not resolvable from the CT data by itself. Superiorization, as presented in this paper, exploits the fact that the simultaneous algebraic reconstruction technique (SART), often used for CT reconstruction, is resilient to perturbations; i.e., it can be modified to produce an output that is as consistent with the CT measurements as the output of unmodified SART, but is more consistent with the complementary data. The application of this superiorized SART method to measured data of a turbine blade demonstrates a clear improvement in the quality of the reconstructed image.
Resonant frequency detection and adjustment method for a capacitive transducer with differential transformer bridge
Authors: Hu M. , Bai Y. Z. , Zhou Z. B. , Li Z. X. , Luo J.
Published: May 2014

The capacitive transducer with differential transformer bridge is widely used in ultra-sensitive space accelerometers due to their simple structure and high resolution. In this paper, the front-end electronics of an inductive-capacitive resonant bridge transducer is analyzed. The analysis result shows that the performance of this transducer depends upon the case that the AC pumping frequency operates at the resonance point of the inductive-capacitive bridge. The effect of possible mismatch between the AC pumping frequency and the actual resonant frequency is discussed, and the theoretical analysis indicates that the output voltage noise of the front-end electronics will deteriorate by a factor of about 3 due to either a 5% variation of the AC pumping frequency or a 10% variation of the tuning capacitance. A pre-scanning method to determine the actual resonant frequency is proposed followed by the adjustment of the operating frequency or the change of the tuning capacitance in order to maintain expected high resolution level. An experiment to verify the mismatching effect and the adjustment method is provided.
Terminal velocity of a bubble in a vertically vibrated liquid
Authors: Romero L. A. , Torczynski J. R. , von Winckel G.
Published: May 2014

We rigorously derive a formula for the terminal velocity of a small bubble in a vertically vibrated viscous incompressible liquid starting from the full Navier-Stokes equations and the exact boundary conditions at the bubble surface. This formula is derived using a perturbation analysis in which the small parameter is the nondimensional amplitude of the pressure oscillation. The analysis does not assume that the bubble remains spherical but does assume that the bubble is axisymmetric. It is shown that the bubble terminal velocity can be computed to second order while computing the full solution only to first order by applying a compatibility condition on the first-order solution. To second order, the bubble terminal velocity is shown to be the net value from an upward steady term and a rectified term that can be downward or upward. The perturbation formula depends on the vibration frequency nondimensionalized by the bubble radius and the liquid kinematic viscosity. We show that our perturbation formula links two heuristically developed formulas for the rectified component, which we denote the velocity-averaged and force-averaged formulas. Our perturbation formula reproduces the velocity-averaged formula for low frequencies and the forced-averaged formula for high frequencies and varies monotonically between these limits for intermediate frequencies. We furthermore develop a high-resolution spectral code specifically to simulate this type of bubble motion. Results from this code verify that the perturbation formula is correct for infinitesimal oscillating pressure amplitudes and suggest that it provides an upper bound for finite amplitudes of the pressure oscillation.
Band structure engineering of anatase TiO2 by metal-assisted P-O coupling
Authors: Wang Jiajun , Meng Qiangqiang , Huang Jing , Li Qunxiang , Yang Jinlong
Published: May 2014

In this work, we demonstrate that the metal-assisted P-O coupling is an effective approach to improve the photoelectrochemical properties of TiO2. The (Sc + P) and (In + P) codoping effects on electronic structures and photocatalytic activities of anatase TiO2 are examined by performing hybrid density functional theory calculations. It is found that the coupling of P dopant with the second-nearest neighboring O atom assisted by acceptor metals (Sc/In) leads to the fully occupied and delocalized intermediate bands within the band gap of anatase TiO2, which is driven by the P-O antibonding states (π*). This metal-assisted P-O coupling can prevent the recombination of photogenerated electron-hole pairs and effectively reduce the band gap of TiO2. Moreover, the band edge alignments in (Sc + P) and (In + P) codoped anatase TiO2 are desirable for water-splitting. The calculated optical absorption curves indicate that (Sc + P) and (In + P) codoping in anatase TiO2 can also effectively enhance the visible light absorption.
Solid-state dimer method for calculating solid-solid phase transitions
Authors: Xiao Penghao , Sheppard Daniel , Rogal Jutta , Henkelman Graeme
Published: May 2014

The dimer method is a minimum mode following algorithm for finding saddle points on a potential energy surface of atomic systems. Here, the dimer method is extended to include the cell degrees of freedom for periodic solid-state systems. Using this method, reaction pathways of solid-solid phase transitions can be determined without having to specify the final state structure or reaction mechanism. Example calculations include concerted phase transitions between CdSe polymorphs and a nucleation and growth mechanism for the A15 to BCC transition in Mo.
Direct and inverse magnetoelectric effects in HoAl3(BO3)4 single crystal
Authors: Freydman A. L. , Balaev A. D. , Dubrovskiy A. A. , Eremin E. V. , Temerov V. L. , Gudim I. A.
Published: May 2014

The direct (MEH-) and inverse (MEE-) magnetoelectric effects in the HoAl3(BO3)4 single crystal are studied. Temperature and magnetic field dependences of permittivity of the crystal are investigated. A relation between the investigated effects was established. It was found that the magnetoelectric effect can exist in crystals without magnetic order or spontaneous polarization. It was shown that the phenomena investigated are due to magnetostriction or magnetoelastic effect. The thermodynamic potential was considered for describing magnetoelectric effect at low magnetic fields. The results obtained are explained within a proposed qualitative microscopic model, based on interplay of configuration of 4f- electron subshell of the rare-earth element and applied magnetic or electric field.
Percolation of gallium dominates the electrical resistance of focused ion beam deposited metals
Authors: Faraby H. , DiBattista M. , Bandaru P. R.
Published: May 2014

Metal deposition through focused ion beam (FIB) based systems is thought to result in material composed of the primary metal from the metallo-organic precursor in addition to carbon, oxygen, and gallium. We determined, through electrical resistance and chemical composition measurements on a wide range of FIB deposited platinum and tungsten lines, that the gallium ion (Ga+) concentration in the metal lines plays the dominant role in controlling the electrical resistivity. Effective medium theory, based on McLachlan's formalisms, was used to describe the relationship between the Ga+ concentration and the corresponding resistivity.
Metamorphic 2.1-2.2 eV InGaP solar cells on GaP substrates
Authors: Tomasulo S. , Nay Yaung K. , Faucher J. , Vaisman M. , Lee M. L.
Published: May 2014

We demonstrate ∼2.1–2.2 eV InyGa1−yP (y = 0.18–0.30) solar cells on GaP substrates for potential use in future high-efficiency multi-junction solar cells. Due to increased direct absorption compared to GaP, the InyGa1−yP solar cells exhibited much higher short-circuit current density than indirect gap GaP solar cells with only a slight decrease in open-circuit voltage. As such, the InyGa1−yP solar cells presented here possessed higher efficiency than comparable GaP solar cells. By taking advantage of strong direct-gap absorption, we believe that metamorphic InyGa1−yP will be an ideal top cell material for future multi-junction devices.
Communication: Quantum molecular dynamics simulation of liquid para-hydrogen by nuclear and electron wave packet approach
Authors: Hyeon-Deuk Kim , Ando Koji
Published: May 2014

Liquid para-hydrogen (p-H2) is a typical quantum liquid which exhibits strong nuclear quantum effects (NQEs) and thus anomalous static and dynamic properties. We propose a real-time simulation method of wave packet (WP) molecular dynamics (MD) based on non-empirical intra- and inter-molecular interactions of non-spherical hydrogen molecules, and apply it to condensed-phase p-H2. The NQEs, such as WP delocalization and zero-point energy, are taken into account without perturbative expansion of prepared model potential functions but with explicit interactions between nuclear and electron WPs. The developed MD simulation for 100 ps with 1200 hydrogen molecules is realized at feasible computational cost, by which basic experimental properties of p-H2 liquid such as radial distribution functions, self-diffusion coefficients, and shear viscosities are all well reproduced.
Disentangling phonon and impurity interactions in δ-doped Si(001)
Authors: Mazzola Federico , Polley Craig M. , Miwa Jill A. , Simmons Michelle Y. , Wells Justin W.
Published: May 2014

We present a study of the phonon and impurity interactions in a shallow two dimensional electron gas formed in Si(001). A highly conductive ultra-narrow n-type dopant δ-layer, which serves as a platform for quantum computation architecture, is formed and studied by angle resolved photoemission spectroscopy (ARPES) and temperature dependent nanoscale 4-point probe (4PP). The bandstructure of the δ-layer state is both measured and simulated. At 100 K, good agreement is only achieved by including interactions; electron-impurity scattering (W0 = 56 to 61 meV); and electron-phonon coupling (λ = 0.14 ± 0.04). These results are shown to be consistent with temperature dependent 4PP resistance measurements which indicate that at 100 K, ≈7∕8 of the measured resistance is due to impurity scattering with the remaining 1/8 coming from phonon interactions. In both resistance and bandstructure measurements, the impurity contribution exhibits a variability of ≈9% for nominally identical samples. The combination of ARPES and 4PP affords a thorough insight into the relevant contributions to electrical resistance in reduced dimensionality electronic platforms.
Effect of thickness and carrier density on the optical polarization of Al0.44Ga0.56N/Al0.55Ga0.45N quantum well layers
Authors: Wierer J. J. , Montaño I. , Crawford M. H. , Allerman A. A.
Published: May 2014

The thickness and carrier density of AlGaN quantum well (QW) layers have a strong influence on the valence subband structure, and the resulting optical polarization and light extraction of ultraviolet light-emitting diodes. An ultraviolet-emitting (270–280 nm) multiple quantum well heterostructure consisting of 3 periods of Al0.44Ga0.56N/Al0.55Ga0.45N with individual layer thicknesses between 2–3.2 nm is studied both experimentally and theoretically. The optical polarization changes to preferentially polarized perpendicular to the QW plane as the QW thickness increases or the carrier density increases. Calculations show these trends are due to (a) a larger decrease in overlap of conduction band to light and heavy hole envelope functions compared to crystal-field split-off envelope functions, and (b) coupling between the valence subbands where higher heavy hole subbands couple to lower light hole and crystal-field split-off subbands. These changes in the valence band have a profound effect on the optical polarization, emission patterns, and eventual light extraction for ultraviolet emitters at these compositions and thicknesses, and need to be controlled to ensure high device efficiency.
Fast and rewritable colloidal assembly via field synchronized particle swapping
Authors: Tierno Pietro , Johansen Tom H. , Fischer Thomas M.
Published: May 2014

We report a technique to realize reconfigurable colloidal crystals by using the controlled motion of particle defects above an externally modulated magnetic substrate. The transport of particles is induced by applying a uniform rotating magnetic field to a ferrite garnet film characterized by a periodic lattice of magnetic bubbles. For filling factor larger than one colloid per bubble domain, the particle current arises from propagating defects where particles synchronously exchange their position when passing from one occupied domain to the next. The amplitude of an applied alternating magnetic field can be used to displace the excess particles via a swapping mechanism, or to mobilize the entire colloidal system at a predefined speed.
Synthesis of ZnO decorated graphene nanocomposite for enhanced photocatalytic properties
Authors: Gayathri S. , Jayabal P. , Kottaisamy M. , Ramakrishnan V.
Published: May 2014

Zinc oxide/Graphene (GZ) composites with different concentrations of ZnO were successfully synthesized through simple chemical precipitation method. The X-ray diffraction pattern and the micro-Raman spectroscopic technique revealed the formation of GZ composite, and the energy dispersive X-ray spectrometry analysis showed the purity of the prepared samples. The ZnO nanoparticles decorated graphene sheets were clearly visible in the field emission scanning electron micrograph. Raman mapping was employed to analyze the homogeneity of the prepared samples. The diffuse-reflectance spectra clearly indicated that the formation of GZ composites promoted the absorption in the visible region also. The photocatalytic activity of ZnO and GZ composites was studied by the photodegradation of Methylene blue dye. The results revealed that the GZ composites exhibited a higher photocatalytic activity than pristine ZnO. Hence, we proposed a simple wet chemical method to synthesize GZ composite and its application on photocatalysis was demonstrated.
Thermal evaporation and characterization of superstrate CdS/Sb2Se3 solar cells
Authors: Luo Miao , Leng Meiying , Liu Xinsheng , Chen Jie , Chen Chao , Qin Sikai , Tang Jiang
Published: May 2014

Sb2Se3 is a very promising absorber material for thin film photovoltaics because of its ideal band gap, strong optical absorption, and non-toxic and earth-abundant constituents. However, only until this year Sb2Se3 solar cell was reported. Here, we present the fabrication and characterization of thermally evaporated superstrate CdS/Sb2Se3 solar cell. Our device achieved a power conversion efficiency of 1.9% (Voc = 300 mV, Jsc = 13.2 mA/cm2, and FF = 48%) and showed good stability. Moreover, using current-voltage measurement, admittance spectroscopy, capacitance-voltage profiling, and drive level capacitance profiling, device characteristics and performance limiting factors are revealed and discussed.
Separation algorithm for bulk lifetime and surface recombination velocity of thick silicon wafers and bricks via time-resolved photoluminescence decay
Authors: Wang Kai , Kampwerth Henner
Published: May 2014

We present a method to simultaneously determine bulk and surface recombination properties using time-resolved photoluminescence (PL) decay. The lifetime separation algorithm makes use of the analytical expression of the asymptotic separation of two time-resolved PL decays corresponding to different excitation wavelengths as well as that of the ratio of two steady-state PL intensities excited by the two different wavelengths. Detailed experimental methods of measuring these two terms are presented and the effect of signal-to-noise ratio is discussed to determine the applicability of this algorithm.
Temperature dependence of the magnetostriction in polycrystalline PrFe1.9 and TbFe2 alloys: Experiment and theory
Authors: Tang Y. M. , Chen L. Y. , Zhang L. , Huang H. F. , Xia W. B. , Zhang S. Y. , Wei J. , Tang S. L. , Du Y. W.
Published: May 2014

A remarkable magnetostriction λ111 as large as 6700 ppm was found at 70 K in PrFe1.9 alloy. This value is even larger than the theoretical maximum of 5600 ppm estimated by the Steven's equivalent operator method. The temperature dependence of λ111 for PrFe1.9 and TbFe2 alloys follows well with the single-ion theory rule, which yields giant estimated λ111 values of about 8000 and 4200 ppm for PrFe1.9 and TbFe2 alloys, respectively, at 0 K. The easy magnetization direction of PrFe1.9 changes from [111] to [100] as temperature decreases, which leads to the abnormal decrease of the magnetostriction λ. The rare earth sublattice moment increases sharply in PrFe1.9 alloy with decreasing temperature, resulting in the remarkably largest estimated value of λ111 at 0 K according to the single-ion theory.
Improvements to laser wakefield accelerated electron beam stability, divergence, and energy spread using three-dimensional printed two-stage gas cell targets
Authors: Vargas M. , Schumaker W. , He Z.-H. , Zhao Z. , Behm K. , Chvykov V. , Hou B. , Krushelnick K. , Maksimchuk A. , Yanovsky V. , Thomas A. G. R.
Published: May 2014

High intensity, short pulse lasers can be used to accelerate electrons to ultra-relativistic energies via laser wakefield acceleration (LWFA) [T. Tajima and J. M. Dawson, Phys. Rev. Lett. 43, 267 (1979)]. Recently, it was shown that separating the injection and acceleration processes into two distinct stages could prove beneficial in obtaining stable, high energy electron beams [Gonsalves et al., Nat. Phys. 7, 862 (2011); Liu et al., Phys. Rev. Lett. 107, 035001 (2011); Pollock et al., Phys. Rev. Lett. 107, 045001 (2011)]. Here, we use a stereolithography based 3D printer to produce two-stage gas targets for LWFA experiments on the HERCULES laser system at the University of Michigan. We demonstrate substantial improvements to the divergence, pointing stability, and energy spread of a laser wakefield accelerated electron beam compared with a single-stage gas cell or gas jet target.
Multi-bands photoconductive response in AlGaN/GaN multiple quantum wells
Authors: Chen G. , Wang X. Q. , Fu K. , Rong X. , Hashimoto H. , Zhang B. S. , Xu F. J. , Tang N. , Yoshikawa A. , Ge W. K. , Shen B.
Published: May 2014

Based on the optical transitions among the quantum-confined electronic states in the conduction band, we have fabricated multi-bands AlGaN/GaN quantum well infrared photodetectors. Crack-free AlGaN/GaN multiple quantum wells (MQWs) with atomically sharp interfaces have been achieved by inserting an AlN interlayer, which releases most of the tensile strain in the MQWs grown on the GaN underlayer. With significant reduction of dark current by using thick AlGaN barriers, photoconductive responses are demonstrated due to intersubband transition in multiple regions with center wavelengths of 1.3, 2.3, and 4 μm, which shows potential applications on near infrared detection.
Nonadiabatic electron dynamics of single-electron transport in a perpendicular magnetic field
Authors: He JianHong , Gao Jie , Guo HuaZhong
Published: May 2014

We present results of our investigation into the nonadiabatic electron dynamics of a moving quantum dot assisted by surface acoustic waves (SAWs) in a perpendicular magnetic field. The measurements show the evolution of a quantized acoustoelectric current in a modulated external field, which provides direct information of the energy spectrum and the occupation of the SAW-induced elliptical dynamical quantum dot. By comparing the magnetic field dependence of the spectrum with that of a somewhat symmetric circular dot, we find the appearance of nonadiabatic excitations at low magnetic fields resulting from the anisotropy of the dot. We also detect the transitions between different quantum states of the elliptical dot, achieved by exploiting the interference of two phase-tuned SAWs. Our results demonstrate that the quantum states in an asymmetric dot are fragile and extremely sensitive to their environment.
High performing phase-based surface plasmon resonance sensing from metallic nanohole arrays
Authors: Cao Z. L. , Wong S. L. , Wu S. Y. , Ho H. P. , Ong H. C.
Published: May 2014

We show the spectral figure-of-merit (FOM) from nanohole arrays can be larger than 1900/RIU by phase-based surface plasmon resonance. By using temporal coupled mode theory, we find the p-s polarization phase jump is the sharpest when both the absorption and radiative decay rates of surface plasmon polaritons are matched, yielding an extremely small spectral differential phase linewidth and thus superior FOM. The result is supported by numerical simulation and experiment. As a demonstration, we show the phase detection outperforms the conventional spectral counterpart significantly by sensing the binding of bovine serum albumin antibodies under identical condition.
Intrinsic spin dependent and ferromagnetic stability on edge saturated zigzag graphene-like carbon-nitride nanoribbons
Authors: Zhang Shuai , Li Chong , Li S. F. , Sun Q. , Guo Z. X. , Jia Yu
Published: May 2014

Using first-principles calculations, we have investigated the electronic and magnetic properties of zigzag graphene-like carbon-nitride nanoribbons (Zg-CNNRs) with mono- and dihydrogen-terminated edges asymmetrically. The results demonstrate that spin-down channel completely dominates the states adjacent Fermi level, which is an intrinsic feature and can be accounted for the valence band maximum derived from the nonbonding N-(px,py) orbitals, instead of the bonding C/N-pz π state. Importantly, ferromagnetic ordering is found to be preferred and the magnetism is entirely localized on the N sites of saturated edge due to its stronger electronegativity. Additionally, various edge saturations are further proposed to try to enhance the ferromagnetic ordering and to manipulate the magnetism distributions of Zg-CNNRs.
Study of valence-band intersublevel transitions in InAs/GaAs quantum dots-in-well infrared photodetectors
Authors: Lao Yan-Feng , Wolde Seyoum , Unil Perera A. G. , Zhang Y. H. , Wang T. M. , Kim J. O. , Schuler-Sandy Ted , Tian Zhao-Bing , Krishna S. S.
Published: May 2014

The n-type quantum dot (QD) and dots-in-well (DWELL) infrared photodetectors, in general, display bias-dependent multiple-band response as a result of optical transitions between different quantum levels. Here, we present a unique characteristic of the p-type hole response, a well-preserved spectral profile, due to the much reduced tunneling probability of holes compared to electrons. This feature remains in a DWELL detector, with the dominant transition contributing to the response occurring between the QD ground state and the quantum-well states. The bias-independent response will benefit applications where single-color detection is desired and also allows achieving optimum performance by optimizing the bias.
High power operation of a nitrogen doped, vanadium compensated, 6H-SiC extrinsic photoconductive switch
Authors: Sullivan J. S.
Published: May 2014

We report the high power operation of nitrogen doped, vanadium compensated, 6H-SiC, extrinsic photoconductive switches with improved vanadium and nitrogen dopant density. Photoconductive switching tests are performed on 1 mm thick, m-plane, switch substrates at switch voltage and currents up to 17 kV and 1.5 kA, respectively. Sub-ohm minimum switch on resistance is achieved for peak optical intensities ≥35 MW/cm2 at 532 nm applied to the switch facet. A reduction of greater than nine orders of magnitude is observed in switch material resistivity between dark and illuminated states.
Selection for residual feed intake affects appetite and body composition rather than energetic efficiency
Authors: Lines D. S. , Pitchford W. S. , Bottema C. D. K. , Herd R. M. , Oddy V. H.
Published: May 2014

Residual feed intake (RFI) is the difference between an animal’s actual feed intake and that which would be expected based on production. This experiment was to test the hypothesis that part of the variation in RFI may be due to differences in energetic efficiency through changes in heat production, these being in part due to differences in protein metabolism. Following three generations of divergent selection for RFI, eight High and eight Low-RFI heifers were fed at both 105% and 180% of predicted maintenance feed requirements. Between-RFI line and feeding-level differences were assessed for energy intake, protein metabolism, heat production, body composition, energy and nitrogen balance and digestibility. The RFI lines did not differ in protein metabolism or heat production. The High-RFI heifers deposited 51% and 56% more subcutaneous fat at the P8 rump and 12/13th rib sites, respectively, with no difference in eye muscle area gain or average daily weight gain. The greater fat deposition of High-RFI heifers was due to a larger ad libitum feed consumption compared with the Low-RFI heifers. Energy and nitrogen balance did not differ between the RFI lines. The energy transactions indicated no difference in the efficiency of energy use on 105% maintenance, although when fed 180% of maintenance the differences in feed intake suggest variation in appetite as the mechanism contributing to RFI. All of the extra energy consumed by High-RFI heifers above maintenance and deposition of protein was associated with additional energy retained as fat. This study suggests that selection for RFI may not lead to improved efficiency of energy use.
Ferdinand Mueller’s Alpine Itinerary
Authors: Home R. W.
Published: May 2014

In the early 1850s, Victoria's newly appointed Government Botanist, Ferdinand Mueller, undertook three remarkable journeys of botanical exploration in the alpine region in the colony's north-east. There has been considerable uncertainty about the route that he followed, especially on his third expedition between November 1854 and March 1855. This paper offers a reconsideration of Mueller's travels in the mountains that takes account of his reports and correspondence, published and unpublished, and also the topography of the region. The conclusions reached have implications for the interpretation of Mueller's collection records from these expeditions. The paper also discusses Mueller's attempt to fix names on various geographical features in the area and suggests why this was unsuccessful.
J. T. Jutson: A Master of Synthesis
Authors: Twidale C. Rowland , Brock Erland J.
Published: May 2014

John Thomas Jutson (1874–1959) spent most of his life as a practising solicitor in Melbourne. He studied the Victorian coast as a hobby in his later years, though he became known for his work on the Sydney shoreline and the proposal that different processes have simultaneously generated platforms at various levels. Between 1911 and 1918, however, Jutson had been employed as a field geologist by the Geological Survey of Western Australia. Drawing on the work of colleagues as well as his own brief field experiences, he produced an explanatory account of the Western Australian landscape that was published in 1914 and reprinted in revised form in 1934 and 1950. In his synthesis he discussed hitherto neglected arid zone landforms and processes. He presented evidence and argument pointing to the plateau and high plain that occupies so much of the interior of the State being a two-stage development. He attributed it to what would later be called etching, resulting in double planation at a regional scale. His innovative interpretations brought Jutson international recognition.
Creative Confluence
Authors: Hoorn Johan F.
Published: May 2014

Creative Confluence is a highly original work, building bridges between physics, biology, technology, economy, organizations, neuropsychology, literature, arts, and cultural history. It is an attempt to explain the process of creativity as a universal principle of nature, cutting through the composition of atoms as well as human design of novel combinations. Creative Confluence is yet another impressive book and a sequel to Epistemics of the Virtual, indicating that perception and imagination operate in close contact. In a clear and light tone, the work holds that rational problem-solving strategies are most relevant in deterministic problem spaces whereas creativity is pertinent in more probabilistic situations. Theories of creativity and innovation are explored by means of computer simulations. Conditionals that favor creativity such as diversity, tolerance, and openness are discussed, forwarding a compelling vision of creative leadership.
The market as a rational and responsible human being
Authors: Nicaise Laurent
Published: May 2014

There has been growing recognition that factors other than fundamental financial information have an impact on investors’ decisions on whether or not to invest in financial products. As the accumulation of information makes it increasingly difficult to process all the data efficiently, it has been shown that the power of imagery tends to compete with that of objective technical indicators. This paper extends existing perspectives on the behavioural effect of agent metaphors and shows that the connected notions of rationality and responsibility implied by some metaphorical themes will induce investors to invest or not in specific stocks.
Appearances and dis/dys-appearances
Authors: El Refaie Elisabeth
Published: May 2014

This article draws on phenomenological and sociological notions of the ‘lived’ body in order to develop a dynamic perspective on embodiment in Conceptual Metaphor Theory. My main argument is that even our most basic sensorimotor experiences are more complex, fluid, and more deeply imbued with socio-cultural meanings than many metaphor scholars assume. While our conscious awareness is ordinarily directed towards the world, making our physical actions and perceptions appear to be natural and straightforward, at times of dysfunction, such as illness and disability, the body suddenly seizes our attention and is perceived as alien. In these moments bodily experience often becomes not just the source, but also the target of metaphorical mappings. I demonstrate the usefulness of the notion of dynamic embodiment by applying it to the example of verbal and visual cancer metaphors.
A CDA Representation of the May 31, 2010 Gaza-Bound Aid Flotilla Raid
Authors: Dastjerdi Hossein Vahid , Abbasian Borojeni Fatemeh
Published: May 2014

News media as both a site and a process of social interaction and ideological construction (van Dijk 1993) play a unique role and carry a signifying power in structuring social thinking and disseminating social knowledge on issues related to national or international agendas, and in representing events in particular ways (Fairclough 1995). Through a comparative analysis of 30 articles from four newspapers on the events of May 31, 2010 Gaza-bound aid flotilla raid and their aftermath, the present study examined the discursive properties of the articles in the process of construction of the events and representation of their participants through in and out-group identity. Using van Dijk’s (1991) approach to news analysis and drawing on the analytical framework of transitivity and lexical cohesion proposed in Halliday (1994), the study investigated the representation of the events and social actors. The results revealed the links between choices of certain discourse strategies realized in certain linguistic forms and the role of ideologies and power relations underlying such forms and strategies.
Whose face to be saved? Mubarak’s or Egypt’s? A pragma-semantic analysis
Authors: Salama Amir H.Y.
Published: May 2014

The 25th of January, 2011 witnessed a wave of political unrest all over Egypt, with repercussions that have re-shaped the future of contemporary Egypt. For the first time in the modern history of Egypt since the 1952 Nasserite revolution, grass-root protestors went to streets chanting slogans against the military regime headed by the (since then ex-) President of Egypt, Hosni Mubarak. This placed the then regime, as well as its mainstay, the National Democratic Party (NDP), in a political crisis on both local and international scales. It is this critical moment that led Mubarak to give his unprecedented speech on February 1st, 2011. The speech has brought about epoch-making political changes in the history of contemporary Egypt. Under public pressure, two seminal declarations were made in this speech: (1) Mubarak’s intention not to nominate himself for a new presidential term; (2) a call on the Houses of Parliament to amend articles 76 and 77 of the constitution concerning the conditions on running for presidency and the period for the presidential term in Egypt. The present paper seeks to answer the following overarching question: what are the discursive strategies used for saving the political face of Mubarak in his speech on February 1st, 2011? I follow a text-analytic framework based on the socio-semantic theory of social actors and the pragmatic models of speech acts and face-threatening acts. The analysis reveals Mubarak’s attempt to save his positive political face as a legitimate President who regarded himself as the official ruler invested with absolute power over Egypt.
Alterations in connexin 43 during diabetic cardiomyopathy: Competition of tyrosine nitration versus phosphorylation 在糖尿病心肌病中间隙连接蛋白43的变化：酪氨酸硝化作用与磷酸化作用的竞争
Authors: Joshi Mandar S. , Mihm Michael J. , Cook Angela C. , Schanbacher Brandon L. , Bauer John Anthony
Published: May 2014

Background

Cardiac conduction abnormalities are observed early in the progression of type 1 diabetes (T1D), but the mechanism(s) involved are undefined. Connexin 43, a critical component of ventricular gap junctions, depends on tyrosine phosphorylation status to modulate channel conductance; changes in connexin 43 content, distribution, and/or phosphorylation status may be involved in cardiac rhythm disturbances. We tested the hypothesis that cardiac content and/or distribution of connexin 43 is altered in a rat model of T1D cardiomyopathy, investigating a mechanistic role for tyrosine.

Methods

Electrocardiographic analyses were conducted during the progression of diabetic cardiomyopathy in rats dosed with streptozotocin (STZ; 65 mg/kg) 3, 7, and 35 days after the induction of diabetes. Following functional analyses, we conducted immunohistochemical and immunoprecipitation studies to assess alterations in connexin 43.

Results

There was significant evidence of ventricular conduction abnormalities (QRS complex, Q‐T interval) as early as 7 days after STZ, persisting throughout the study. Connexin 43 levels were increased 7 days after STZ and remained elevated throughout the study. Connexin 40 content was unchanged relative to controls throughout the study. Changes in connexin 43 distribution were also observed: connexin 43 staining was dispersed from myocyte short axis junctions. Connexin 43 tyrosine phosphorylation declined during the progression of diabetes, with concurrent increases in tyrosine nitration.

Conclusions

The data suggest that changes in connexin 43 content and distribution occur during experimental diabetes and likely contribute to alterations in cardiac function, and that oxidative modification of tyrosine‐mediated signaling may play a mechanistic role.
Integrating demographic data: towards a framework for monitoring wildlife populations at large spatial scales
Authors: Robinson Robert A. , Morrison Catriona A. , Baillie Stephen R.
Published: May 2014

Landscapes are becoming increasingly intensively managed resulting in greater anthropogenic disturbance of ecosystems. Effective policies for conservation and management of wildlife populations will require a mechanistic understanding of the processes underlying the population responses to these changes. Detailed demographic studies are often of individual populations in relatively stable habitats, whereas there is a need to characterize demographic variation at larger scales in wider landscapes that are subject to environmental change.

We use long‐term (18–46 years) data sets, gathered by volunteers acrossBritain, to parameterizeBayesian state‐space demographic population models for 17 widely occurring bird species. As some demographic processes were not quantified directly, we introduce a scaling parameter (ρ) to account for this unmeasured variation, and assess the extent to which this influences our ability to understand the processes driving population change.

The population models provided a good fit to the population trajectory in all but one species (the nocturnal tawny owlStrix aluco). The scaling parameter generally showed little annual variation and did not make a major contribution (<12%) to population change among passerine species. For five non‐passerine species, the contribution was still not large (11–21%), but did indicate the importance of unmeasured demographic variables in these species.

We were able to retrieve known demographic signals both within and across species. The importance of the nest failure rates was greater for species that construct nests in open rather than cavity situations. We also confirmed the demographic causes of population decline in two species of conservation concern, song thrush and lapwing, as changes in juvenile survival and reproductive success respectively. Furthermore, we show that population dynamics of declining species are generally driven more by recruitment than increasing species (for which variation in adult survival is more important).

These analyses demonstrate that volunteer‐based monitoring programmes can provide insight into population changes at large spatial scales across a range of species. By facilitating the combination of data sets on different demographic parameters, the integrated approach adopted here allows important demographic parameters to be identified, even if they are not measured directly.
Do cattle (Bos taurus) retain an association of a visual cue with a food reward for a year?
Authors: Hirata Masahiko , Takeno Nozomi
Published: May 2014

Use of visual cues to locate specific food resources from a distance is a critical ability of animals foraging in a spatially heterogeneous environment. However, relatively little is known about how long animals can retain the learned cue–reward association without reinforcement. We compared feeding behavior of experienced and naive Japanese Black cows (Bos taurus) in discovering food locations in a pasture. Experienced animals had been trained to respond to a visual cue (plastic washtub) for a preferred food (grain‐based concentrate) 1 year prior to the experiment, while naive animals had no exposure to the cue. Cows were tested individually in a test arena including tubs filled with the concentrate on three successive days (Days 1–3). Experienced cows located the first tub more quickly and visited more tubs than naive cows on Day 1 (usually P < 0.05), but these differences disappeared on Days 2 and 3. The performance of experienced cows tended to increase from Day 1 to Day 2 and level off thereafter. Our results suggest that Japanese Black cows can associate a visual cue with a food reward within a day and retain the association for 1 year despite a slight decay.
All‐trans retinoic acid improves goat oocyte nuclear maturation and reduces apoptotic cumulus cells during in vitro maturation
Authors: Pu Yong , Wang Zhangfan , Bian Yani , Zhang Fei , Yang Pan , Li Yunsheng , Zhang Yunhai , Liu Ya , Fang Fugui , Cao Hongguo , Zhang Xiaorong
Published: May 2014

All‐trans retinoic acid (t‐RA) is a natural component and representative physiologically active metabolite of vitamin A, having multiple physiologic functions. The objective of this study was to evaluate the effect of t‐RA on goat oocyte maturation and cumulus cell apoptosis during in vitro maturation (IVM). Immature goat cumulus‐oocyte complexes (COCs) were matured in vitro in the absence or presence of t‐RA at concentrations of 10 nmol/L, 100 nmol/L and 1000 nmol/L. Oocyte maturation and embryo development were assessed by polar body formation and parthenogenetic activation, respectively. Oocyte survival was checked by Trypan blue staining. Apoptosis of cumulus cells was analyzed by terminal deoxynucleotidyl transferase nick end labeling staining and quantitative real‐time PCR. In comparison with the control group, 100 nmol/L and 10 nmol/L t‐RA significantly improved goat nuclear oocyte maturation and survival (P < 0.05). Addition of 1000 nmol/L t‐RA improved nuclear maturation (P < 0.05), but had no effect on survival of goat oocytes. t‐RA had no positive effect on goat parthenogenetic embryonic cleavage, blastocyst formation or total cell numbers. However, t‐RA inhibits the apoptosis of cumulus cells (P < 0.01). t‐RA treatment up‐regulated the expression of B‐cell lymphoma 2 (BCL‐2), catalase (CAT) (P < 0.05) and down‐regulated the expression of Caspase‐8 (P < 0.05). In conclusion, t‐RA has positive effects on goat oocyte nuclear maturation and reduces apoptotic cumulus cells during IVM.
Effect of increasing levels of seven tree species extracts added to a high concentrate diet on in vitro rumen gas output
Authors: Salem Abdelfattah Z. M. , Kholif Ahmed E. , Elghandour Mona M. Y. , Hernandez Saul R. , Domínguez‐Vara Ignacio A. , Mellado Miguel
Published: May 2014

This study was conducted to investigate the effects of increasing levels of extracts of Byrsonima crassifolia, Celtis pallida, Enterolobium cyclocarpum, Fraxinus excelsior, Ficus trigonata, Phoradendrom brevifolium and Prunus domestica on in vitro gas production (GP) and ruminal fermentation of a high concentrate diet. Plant extracts were prepared at 1 g dry matter (DM)/8 mL of solvent mixture (methanol : ethanol : water, 1:1:8) and added at levels of 0, 0.6, 1.2 and 1.8 mL/g DM of a high concentrate diet. In vitro GP was recorded at 2, 4, 6, 8, 10, 12, 24, 48 and 72 h of incubation. Increasing addition of extracts linearly increased (P < 0.001), the GP24, GP48 and GP72 (mL/g DM), and linearly decreased (P < 0.001), the discrete GP lag time. Moreover, increasing extract doses linearly increased (P < 0.001) the asymptotic GP and decreased (P < 0.001) the rate of GP. GP6 was not impacted by treatments and GP12 increased linearly (P = 0.01) with increasing addition of extracts. Rumen pH declined linearly (P < 0.05) with increasing doses of extracts added. As no interactions (P > 0.05) occurred between the extracts and doses, it could be conclude that all extracts positively modified rumen fermentation at doses of 1.2 to 1.8 mL extract/g diet DM.