bluuebunny/crossref_metadata_2025 huggingface dataset:
Large piezoelectricity in Pb-free 0.96(K0.5Na0.5)0.95Li0.05Nb0.93Sb0.07O3−0.04BaZrO3 ceramic: A perspective from microstructure
Authors: Gao Jinghui , Hao Yanshuang , Ren Shuai , Kimoto Takayoshi , Fang Minxia , Li Huiying , Wang Yu , Zhong Lisheng , Li Shengtao , Ren Xiaobing
Published: February 2015

We employ transmission electron microscopy to explore the reason for large piezoelectricity (d33≈400pC/N) in a Pb-free 0.96(K0.5Na0.5)0.95Li0.05Nb0.93Sb0.07O3 −0.04BaZrO3 ceramic from microstructure. The result shows that the high piezoelectricity corresponds to a miniaturized nanodomain configuration in a domain hierarchy. The nanodomains disappear on heating accompanied by a reduction in d33 value. Further convergent beam electron diffraction study reveals a coexistence of tetragonal and orthorhombic phase, which indicates that large piezoelectricity of KNLNS0.07-BZ may stem from easy polarization rotation due to low polarization anisotropy on the tetragonal-orthorhombic phase boundary.
Electric response of a metal-molecule-metal junction to laser pulse by solving hierarchical equations of motion
Authors: Cao Hui , Zhang Mingdao , Tao Tao , Song Mingxia , Zhang Chaozhi
Published: February 2015

We have combined the quantum dissipative theory and the time dependent density functional theory to perform the first principle calculation of laser induced quantum dynamical electron transport through a molecule weak bridged to two electrodes. The formalism of hierarchical equations of motion based on non-equilibrium Green’s function theory has been taken in this work. Numerical simulations of optical absorption spectra of benzene, laser induced transient current without and with bias, charge pumping effect, as well as the spectrum analysis from the current in Au-benzene-Au molecular junction are presented and discussed.
Ultrafast shock-induced chemistry in carbon disulfide probed with dynamic ellipsometry and transient absorption spectroscopy
Authors: Brown Kathryn E. , Bolme Cynthia A. , McGrane Shawn D. , Moore David S.
Published: February 2015

We used transient visible/near-infrared absorption spectroscopy and ultrafast dynamic ellipsometry to characterize carbon disulfide (CS2) shocked with an ultrafast laser pulse. We found a volume-decreasing reaction, characterized by the deviation of the shock and particle velocity (us and up) points from the unreacted Hugoniot, above up = 1.5 km/s. This result contrasts with literature plate-impact data, which found the reaction-induced deviation from the unreacted Hugoniot to occur at up = 1.2 km/s. We attribute this disparity to the difference in timescale between plate-impact experiments (ns to μs) and our ultrafast experiments (sub-ns), as our ultrafast experiments require higher shock pressures and temperatures for an observable reaction. The volume-decreasing reaction was accompanied by a large increase in absorption of the reaction products, necessitating the use of impedance matching techniques to characterize the us-up points above the reaction cusp. Using transient absorption spectroscopy, we discovered a change in the absorption spectrum for shock strengths below and above the volume-decreasing reaction, suggesting there are multiple chemical reactions in CS2 shocked to above 7.4 GPa in 300 ps.
The infrared spectrum of the He–C2D2 complex
Authors: Moazzen-Ahmadi N. , McKellar A. R. W. , Fernández Berta , Farrelly David
Published: February 2015

Spectra of the helium-acetylene complex are elusive because this weakly bound system lies close to the free rotor limit. Previously, limited assignments of He–C2D2 transitions in the R(0) region of the ν3 fundamental band (≈2440 cm−1) were published. Here, new He–C2D2 infrared spectra of this band are obtained using a tunable optical parametric oscillator laser source to probe a pulsed supersonic slit jet expansion from a cooled nozzle, and the analysis is extended to the weaker and more difficult P(1) and R(1) regions. A term value approach is used to obtain a consistent set of “experimental” energy levels. These are compared directly with calculations using two recently reported ab initio intermolecular potential energy surfaces, which exhibit small but significant differences. Rovibrational energies for the He–C2H2 complex are also calculated using both surfaces. A Coriolis model, useful for predicting spectral intensities, is used to interpret the energy level patterns, and a comparison with the isoelectronic complex He–CO is made.
Dynamics of laminar circular jet impingement upon convex cylinders
Authors: New T. H. , Long J.
Published: February 2015

Flow dynamics associated with a laminar circular jet impinging upon a convex cylinder has been investigated by laser-induced fluorescence and digital particle-image velocimetry techniques. Cylinder-to-jet diameter ratios of 1, 2, and 4 were investigated, while the jet-to-cylinder separation distance was kept at four jet diameters throughout. Flow visualization and λ2 criterion results show that once the jet ring-vortices impinge upon the cylindrical surface, they move away from the impingement point by wrapping themselves partially around the surface. As the cylinder diameter increases, wall boundary layer separation, vortex dipole formation, and separation locations are initiated earlier along the cylindrical surface, producing significantly larger wakes. Along the cylinder straight-edges, ring-vortex cores are significantly smaller after impingement. This is due to accentuated vortex-stretching caused by partial wrapping around the cylindrical surface by the ring-vortices, on top of their movement away from the impingement point. Interestingly, vortex dipoles demonstrate a strong tendency to travel upstream and interact with other upstream vortex dipoles, instead of moving downstream gradually seen for flat-surface jet-impingements. Wall shear stress results are also presented to quantify the effects of cylinder diameter-ratio on surface skin friction distribution. Finally, these preceding observations are corroborated and explained in a three-dimensional flow dynamics model presented here.
Multidiagnostic analysis of ion dynamics in ultrafast laser ablation of metals over a large fluence range
Authors: Anoop K. K. , Polek M. P. , Bruzzese R. , Amoruso S. , Harilal S. S.
Published: February 2015

The dynamics of ions in ultrafast laser ablation of metals is studied over fluences ranging from the ablation threshold up to ≈75 J/cm2 by means of three well-established diagnostic techniques. Langmuir probe, Faraday cup, and spectrally resolved intensified charge coupled device imaging simultaneously monitored the ions produced during ultrafast laser ablation of a pure copper target with 800 nm, ≈50 fs, Ti: Sapphire laser pulses. The fluence dependence of ion yield is analyzed, resulting in the observance of three different regimes. The specific ion yield shows a maximum at about 4–5 J/cm2, followed by a gradual reduction and a transition to a high-fluence regime above ≈50 J/cm2. The fluence dependence of the copper ions angular distribution is also analyzed, observing a gradual increase in forward-peaking of Cu ions for fluences up to ≈10 J/cm2. A broader ion component is observed at larger angles for fluences larger than ≈10 J/cm2. Finally, an experimental characterization of the ionic angular distribution for several metallic targets (Mg, Al, Cr, Fe, Cu, and W) is carried out at a relatively high fluence of ≈66 J/cm2. Interestingly, the ion emission from the volatile metals shows a narrow, forward-peaked distribution, and a high peak ion yield compared to the refractory metals. Moreover, the width of ionic angular distributions presents a striking correlation with the peak ion yield.
Effect of growth temperature on structural, magnetic, and transport properties of Co2Cr0.6Fe0.4Al Heusler alloy sputtered thin films
Authors: Yadav Anjali , Chaudhary Sujeet
Published: February 2015

The effect of growth temperature TS on crystallographic structure, DC-magnetization, and electrical transport behavior of pulsed dc-magnetron sputtered Co2Cr0.6Fe0.4Al Heusler alloy thin films has been investigated. The increase in TS enhances the crystallite size, structural ordering in these films, eventually resulting in the increase in saturation magnetization to 2.4 μB/f.u. The (220) textured growth of thin films induces an in-plane magnetic anisotropy of ∼2.1 × 104 erg/cc in these films. The improvement in structural ordering is accompanied with the systematic increase in resistivity ratio ρ(300)/ρ(20 K) and also with the change in sign of temperature coefficients of resistivity from negative to positive at TS = 500 °C. In addition, a resistivity minimum is observed at low temperature in the films deposited at TS>400 °C. The resistivity behavior at low temperature is governed by e-e scattering (T2 dependence), one-magnon scattering (T3 dependence), and weak localization effect (T1/2). However at higher temperature, the resistivity behavior is governed by Tn power law, and the value of n was found to be 1.35 and 0.91 for the films grown at 500 and 600 °C, respectively. The anomalous Hall Effect studies revealed the presence of side-jump scattering mechanism in Hall resistivity consistent with the structural, transport, and DC-magnetization measurements. Nearly, temperature independent Hall sensitivity behavior is observed for these samples in a moderate field range from 0 to 0.3 T, which shows the suitability of the material for developing Hall sensors.
Self-assembly and structural relaxation in a model ionomer melt
Authors: Goswami Monojoy , Borreguero Jose M. , Sumpter Bobby G.
Published: February 2015

Molecular dynamics simulations are used to understand the self-assembly and structural relaxation in ionomer melts containing less than 10% degree of ionization on the backbone. The self-assembly of charged sites and counterions shows structural ordering and agglomeration with a range of structures that can be achieved by changing the dielectric constant of the medium. The intermediate scattering function shows a decoupling of charge and counterion relaxation at longer length scales for only high dielectric constant and at shorter length scales for all dielectric constants. Overall, the slow structural decay of counterions in the strongly correlated ionomer system closely resembles transport properties of semi-flexible polymers.
Gigahertz-gated InGaAs/InP single-photon detector with detection efficiency exceeding 55% at 1550 nm
Authors: Comandar L. C. , Fröhlich B. , Dynes J. F. , Sharpe A. W. , Lucamarini M. , Yuan Z. L. , Penty R. V. , Shields A. J.
Published: February 2015

We report on a gated single-photon detector based on InGaAs/InP avalanche photodiodes (APDs) with a single-photon detection efficiency exceeding 55% at 1550 nm. Our detector is gated at 1 GHz and employs the self-differencing technique for gate transient suppression. It can operate nearly dead time free, except for the one clock cycle dead time intrinsic to self-differencing, and we demonstrate a count rate of 500 Mcps. We present a careful analysis of the optimal driving conditions of the APD measured with a dead time free detector characterization setup. It is found that a shortened gate width of 360 ps together with an increased driving signal amplitude and operation at higher temperatures leads to improved performance of the detector. We achieve an afterpulse probability of 7% at 50% detection efficiency with dead time free measurement and a record efficiency for InGaAs/InP APDs of 55% at an afterpulse probability of only 10.2% with a moderate dead time of 10 ns.
Illusion optics: Optically transforming the nature and the location of electromagnetic emissions
Authors: Yi Jianjia , Tichit Paul-Henri , Burokur Shah Nawaz , de Lustrac André
Published: February 2015

Complex electromagnetic structures can be designed by using the powerful concept of transformation electromagnetics. In this study, we define a spatial coordinate transformation that shows the possibility of designing a device capable of producing an illusion on an antenna radiation pattern. Indeed, by compressing the space containing a radiating element, we show that it is able to change the radiation pattern and to make the radiation location appear outside the latter space. Both continuous and discretized models with calculated electromagnetic parameter values are presented. A reduction of the electromagnetic material parameters is also proposed for a possible physical fabrication of the device with achievable values of permittivity and permeability that can be obtained from existing well-known metamaterials. Following that, the design of the proposed antenna using a layered metamaterial is presented. Full wave numerical simulations using Finite Element Method are performed to demonstrate the performances of such a device.
A model for thermal oxidation of Si and SiC including material expansion
Authors: Christen T. , Ioannidis A. , Winkelmann C.
Published: February 2015

A model based on drift-diffusion-reaction kinetics for Si and SiC oxidation is discussed, which takes the material expansion into account with an additional convection term. The associated velocity field is determined self-consistently from the local reaction rate. The approach allows a calculation of the densities of volatile species in an nm-resolution at the oxidation front. The model is illustrated with simulation results for the growth and impurity redistribution during Si oxidation and for carbon and silicon emission during SiC oxidation. The approach can be useful for the prediction of Si and/or C interstitial distribution, which is particularly relevant for the quality of metal-oxide-semiconductor electronic devices.
One-dimensional particle-in-cell simulation on the influence of electron and ion temperature on the sheath expansion process in the post-arc stage of vacuum circuit breaker
Authors: Mo Yongpeng , Shi Zongqian , Jia Shenli , Wang Lijun
Published: February 2015

The inter-contact region of vacuum circuit breakers is filled with residual plasma at the moment when the current is zero after the burning of metal vapor arc. The residual plasma forms an ion sheath in front of the post-arc cathode. The sheath then expands towards the post-arc anode under the influence of a transient recovery voltage. In this study, a one-dimensional particle-in-cell model is developed to investigate the post-arc sheath expansion. The influence of ion and electron temperatures on the decrease in local plasma density at the post-arc cathode side and post-arc anode side is discussed. When the decay in the local plasma density develops from the cathode and anode sides into the high-density region and merges, the overall plasma density in the inter-contact region begins to decrease. Meanwhile, the ion sheath begins to expand faster. Furthermore, the theory of ion rarefaction wave only explains quantitatively the decrease in the overall plasma density at relatively low ion temperatures. With the increase of ion temperature to certain extent, another possible reason for the decrease in the overall plasma density is proposed and results from the more active thermal diffusion of plasma.
Effect of manganese doping of BaSrTiO3 on diffusion and domain wall pinning
Authors: Nadaud Kevin , Borderon Caroline , Renoud Raphaël , Gundel Hartmut W.
Published: February 2015

In the present paper, the influence of manganese doping on the dielectric properties of BaSrTiO3 thin films is presented. The real and imaginary parts of the material's permittivity have been measured in a large frequency range (100 Hz–1 MHz) and as a function of the electric field. The tunability and the figure of merit of the material have been obtained from the measurement of the permittivity under an applied DC bias electric field. For the undoped material, the dielectric losses become important for a large DC bias which leads to breakdown. At a suitable dopant rate, this effect disappears. In order to better understand the origin of the related phenomena, we measure the permittivity as a function of the AC excitation amplitude and we decompose the obtained permittivity with the hyperbolic law. This enables to extract the different contributions of the bulk (low frequency diffusion and high frequency lattice relaxation) and of the domain wall motions (vibration and pinning/unpinning) to the material's dielectric permittivity and to understand the effect of manganese doping on each contribution. Knowledge of the related mechanisms allows us to establish the optimum dopant rate (mainly conditioned by the lattice contribution) and to reduce the domain wall motion, which finally is beneficial for the desired properties of the ferroelectric thin film. A particular attention is paid to low frequency diffusion, an especially harmful effect when a DC biasing is mandatory (tunable electronic component in mobile telecommunication devices for example).
Enhancement in the structure quality of ZnO nanorods by diluted Co dopants: Analyses via optical second harmonic generation
Authors: Liu Chung-Wei , Chang Shoou-Jinn , Brahma Sanjaya , Hsiao Chih-Hung , Chang Feng Ming , Wang Peng Han , Lo Kuang-Yao
Published: February 2015

We report a systematic study about the effect of cobalt concentration in the growth solution over the crystallization, growth, and optical properties of hydrothermally synthesized Zn1−xCoxO [0 ≤ x ≤ 0.40, x is the weight (wt.) % of Co in the growth solution] nanorods. Dilute Co concentration of 1 wt. % in the growth solution enhances the bulk crystal quality of ZnO nanorods, and high wt. % leads to distortion in the ZnO lattice that depresses the crystallization, growth as well as the surface structure quality of ZnO. Although, Co concentration in the growth solution varies from 1 to 40 wt. %, the real doping concentration is limited to 0.28 at. % that is due to the low growth temperature of 80 °C. The enhancement in the crystal quality of ZnO nanorods at dilute Co concentration in the solution is due to the strain relaxation that is significantly higher for ZnO nanorods prepared without, and with high wt. % of Co in the growth solution. Second harmonic generation is used to investigate the net dipole distribution from these coatings, which provides detailed information about bulk and surface structure quality of ZnO nanorods at the same time. High quality ZnO nanorods are fabricated by a low-temperature (80 °C) hydrothermal synthesis method, and no post synthesis treatment is needed for further crystallization. Therefore, this method is advantageous for the growth of high quality ZnO coatings on plastic substrates that may lead toward its application in flexible electronics.
Towards nonvolatile magnetic crossbar arrays: A three-dimensional-integrated field-coupled domain wall gate with perpendicular anisotropy
Authors: Breitkreutz Stephan , Eichwald Irina , Ziemys Grazvydas , Hiblot Gaspard , Csaba György , Schmitt-Landsiedel Doris , Becherer Markus
Published: February 2015

A novel three-dimensional (3D)-integrated domain wall gate (DWG) providing direct control of the DW propagation in a magnetic nanowire with perpendicular magnetic anisotropy is presented. The pinning of field-driven DWs in a notch is controlled by the fringing fields of a subjacent gate magnet. Depending on the state of the gate magnet, the propagating DW is either pinned in the notch or its movement is supported. Theoretical calculations of controlled DW pinning are shown. We experimentally demonstrate control of the DW motion in magnetic nanowires by other domains in a separated gate layer using magnetic force microscopy. Regarding potential applications, the 3D DWG enables storing and buffering of magnetic domains in order to control the signal flow of 3D-integrated perpendicular nanomagnetic logic. Furthermore, due to the uniformity of input, output, and gate contact, the 3D DWG can act as nonvolatile logic device in order to realize field-driven logic gates and magnetic crossbar arrays.
Induction-detection electron spin resonance with spin sensitivity of a few tens of spins
Authors: Artzi Yaron , Twig Ygal , Blank Aharon
Published: February 2015

Electron spin resonance (ESR) is a spectroscopic method that addresses electrons in paramagnetic materials directly through their spin properties. ESR has many applications, ranging from semiconductor characterization to structural biology and even quantum computing. Although it is very powerful and informative, ESR traditionally suffers from low sensitivity, requiring many millions of spins to get a measureable signal with commercial systems using the Faraday induction-detection principle. In view of this disadvantage, significant efforts were made recently to develop alternative detection schemes based, for example, on force, optical, or electrical detection of spins, all of which can reach single electron spin sensitivity. This sensitivity, however, comes at the price of limited applicability and usefulness with regard to real scientific and technological issues facing modern ESR which are currently dealt with conventional induction-detection ESR on a daily basis. Here, we present the most sensitive experimental induction-detection ESR setup and results ever recorded that can detect the signal from just a few tens of spins. They were achieved thanks to the development of an ultra-miniature micrometer-sized microwave resonator that was operated at ∼34 GHz at cryogenic temperatures in conjunction with a unique cryogenically cooled low noise amplifier. The test sample used was isotopically enriched phosphorus-doped silicon, which is of significant relevance to spin-based quantum computing. The sensitivity was experimentally verified with the aid of a unique high-resolution ESR imaging approach. These results represent a paradigm shift with respect to the capabilities and possible applications of induction-detection-based ESR spectroscopy and imaging.
Theoretical study of phosphorene tunneling field effect transistors
Authors: Chang Jiwon , Hobbs Chris
Published: February 2015

In this work, device performances of tunneling field effect transistors (TFETs) based on phosphorene are explored via self-consistent atomistic quantum transport simulations. Phosphorene is an ultra-thin two-dimensional (2-D) material with a direct band gap suitable for TFETs applications. Our simulation shows that phosphorene TFETs exhibit subthreshold slope below 60 mV/dec and a wide range of on-current depending on the transport direction due to highly anisotropic band structures of phosphorene. By benchmarking with monolayer MoTe2 TFETs, we predict that phosphorene TFETs oriented in the small effective mass direction can yield much larger on-current at the same on-current/off-current ratio than monolayer MoTe2 TFETs. It is also observed that a gate underlap structure is required for scaling down phosphorene TFETs in the small effective mass direction to suppress the source-to-drain direct tunneling leakage current.
Dropwise condensation on a hydrophobic probe-tip for manipulating micro-objects
Authors: Fan Zenghua , Wang Lefeng , Rong Weibin , Sun Lining
Published: February 2015

A capillary-gripping method that enables micro-objects to be picked up flexibly and reliably is described. By controlling the dropwise condensation on a probe tip, the volume of the water droplet on the hydrophobic tip surface can be dynamically varied, which helps to establish appropriate capillary lifting forces during micromanipulation tasks. Droplet formation and the capillary lifting forces generated during the manipulation process were experimentally characterized. Micromanipulation experiments using a customized motion platform equipped with viewing microscopes were conducted to verify the performance potential of this method. A 100% success rate in 200 trials was achieved in picking up and manipulating polystyrene microspheres with radii of 20–50 μm.
PEDOT:PSS emitters on multicrystalline silicon thin-film absorbers for hybrid solar cells
Authors: Junghanns Marcus , Plentz Jonathan , Andrä Gudrun , Gawlik Annett , Höger Ingmar , Falk Fritz
Published: February 2015

We fabricated an efficient hybrid solar cell by spin coating poly(3,4-ethylene-dioxythiophene):polystyrenesulfonate (PEDOT:PSS) on planar multicrystalline Si (mc-Si) thin films. The only 5 μm thin Si absorber layers were prepared by diode laser crystallization of amorphous Si deposited by electron beam evaporation on glass. On these absorber layers, we studied the effect of SiOx and Al2O3 terminated Si surfaces. The short circuit density and power conversion efficiency (PCE) of the mc-Si/Al2O3/PEDOT:PSS solar cell increase from 20.6 to 25.4 mA/cm2 and from 7.3% to 10.3%, respectively, as compared to the mc-Si/SiOx/PEDOT:PSS cell. Al2O3 lowers the interface recombination and improves the adhesion of the polymer film on the hydrophobic mc-Si thin film. Open circuit voltages up to 604 mV were reached. This study demonstrates the highest PCE so far of a hybrid solar cell with a planar thin film Si absorber.
Reconfigurable and ultra-sensitive in-line Mach-Zehnder interferometer based on the fusion of microfiber and microfluid
Authors: Gao Shecheng , Zhang Weigang , Zhang Hao , Zhang Chonglei
Published: February 2015

A reconfigurable Mach-Zenhnder interferometer (MZI) based on a microfluidic cavity (MFC) constructed by embedding a microfiber between two segments of single-mode fibers with pre-designed lateral offset has been proposed and experimentally demonstrated. The MFC serves as an interference arm with an eccentric annular cross section and allows convenient sample (gas or liquids) replacement procedure. The microfiber works as the other interference arm that provides the proposed device with ease of reconstruction and also enhances the force sensitivity. The re-configurability and the ultra-wide tuning sensitivity range are demonstrated by immersing the MZI constructed with a 484 μm-long-MFC and a microfiber 44 μm in diameter in different droplets. Ultrahigh sensitivities of 34.65 nm/°C (∼88 380 nm/RIU) and −493.7 nm/N (∼−590 pm/με) are experimentally achieved using a droplet with a refractive index of ∼1.44.
Intake, apparent digestibility, and methane emission in bulls receiving a feed supplement of monensin, virginiamycin, or a combination
Authors: Pereira da Fonseca Marcelina , Borges Ana Luiza da Costa Cruz , Reis e Silva Ricardo , Lage Helena Ferreira , Ferreira Alexandre Lima , Lopes Fernando César Ferraz , Pancoti Carlos Giovani , Rodrigues José Avelino Santos
Published: February 2015

The aim of this study was to evaluate the effects of the feed supplements monensin, virginiamycin, or a combination of the two, on intake, digestibility, and methane emission in the male cattle breed F1 Holstein × Gir. We used a complete randomised design with four treatments consisting of the control, monensin, virginiamycin, and a combination of the two. The basal diets were composed of sorghum silage with Tanzania grass and the concentrate in the 1 : 1 ratio. Nutrient intake (P > 0.05) and the apparent digestibility coefficients (P > 0.05) were not affected by the supplementation with monensin, virginiamycin, or both. The combination of the supplements did affect methane emission (P < 0.05) when expressed in L/day, L/(kg DM), and L/(kg DM digestible). The lowest methane production was obtained with the combination of the supplements.
‘There’s only one enabler; come up, help us’: staff perspectives of barriers and enablers to continuous quality improvement in Aboriginal primary health-care settings in South Australia
Authors: Newham Jo , Schierhout Gill , Bailie Ross , Ward Paul R.
Published: February 2015

This paper presents the findings from a qualitative study, which sought to investigate the barriers and enablers to implementation of a continuous quality improvement (CQI) program by health-care professionals in Aboriginal primary health-care services in South Australia. Eighteen semi-structured interviews across 11 participating services were conducted alongside CQI implementation activities. Multiple barriers exist, from staff perspectives, which can be categorised according to different levels of the primary health-care system. At the macro level, barriers related to resource constraints (workforce issues) and access to project support (CQI coordinator). At the meso level, barriers related to senior level management and leadership for quality improvement and the level of organisational readiness. At the micro level, knowledge and attitudes of staff (such as resistance to change; lack of awareness of CQI) and lack of team tenure were cited as the main barriers to implementation. Staff identified that successful and sustained implementation of CQI requires both organisational systems and individual behaviour change. Improvements through continuing regional level collaborations and using a systems approach to develop an integrated regional level CQI framework, which includes building organisational and clinic team CQI capacity at the health centre level, are recommended. Ideally, this should be supported at the broader national level with dedicated funding.
Eucalyptus reforestation induces soil water repellency
Authors: Walden L. L. , Harper R. J. , Mendham D. S. , Henry D. J. , Fontaine J. B.
Published: February 2015

There is an increasing interest in eucalypt reforestation for a range of purposes in Australia, including pulp-wood production, carbon mitigation and catchment water management. The impacts of this reforestation on soil water repellency have not been examined despite eucalypts often being associated with water repellency and water repellency having impacts on water movement across and within soils. To investigate the role of eucalypt reforestation on water repellency, and interactions with soil properties, we examined 31 sites across the south-west of Western Australia with paired plots differing only in present land use (pasture v. plantation). The incidence and severity of water repellency increased in the 5–8 years following reforestation with Eucalyptus globulus. Despite this difference in water repellency, there were no differences in soil characteristics, including soil organic carbon content or composition, between pasture and plantation soils, suggesting induction by small amounts of hydrophobic compounds from the trees. The incidence of soil water repellency was generally greater on sandy-surfaced (<10% clay content) soils; however, for these soils 72% of the pasture sites and 31% of the plantation were not water repellent, and this was independent of measured soil properties. Computer modelling revealed marked differences in the layering and packing of waxes on kaolinite and quartz surfaces, indicating the importance of interfacial interactions in the development of soil water repellency. The implications of increased water repellency for the management of eucalyptus plantations are considered.
Soil organic carbon fractions under conventional and no-till management in a long-term study in southern Spain
Authors: Carbonell-Bojollo R. , González-Sánchez E. J. , Ruibérriz de Torres M. Repullo , Ordóñez-Fernández R. , Domínguez-Gimenez J. , Basch G.
Published: February 2015

In dryland farming systems under a Mediterranean climate, soil quality and productivity can be enhanced by increasing the content of soil organic carbon (SOC) through alternative soil management systems. Some fractions of C are directly involved in increasing total SOC and therefore in enhancing any benefits in terms of soil properties. This study compares the viability of no-till farming (NT) with conventional (traditional) tillage (TT) for improving SOC levels. The influence of management practices was investigated for different fractions of C (particulate OC, active OC, humic acids, fulvic acids) and CO2 emissions in clayey soils in the south of Spain. The experiment was conducted over three farming seasons (2006–07, 2007–08 and 2008–09) covering a crop rotation of peas (Pisum sativum L.), wheat (Triticum aestivum L.) and sunflowers (Helianthus annuus L.). The NT system improved the levels of the different fractions of C in the surface soil and reduced the amount of CO2 released into the atmosphere compared with the TT system. Generally, the relationship between CO2 and SOC content was greater in soils under NT for the farming seasons sampled.
Carbon dynamics from carbonate dissolution in Australian agricultural soils
Authors: Ahmad Waqar , Singh Balwant , Dalal Ram C. , Dijkstra Feike A.
Published: February 2015

Land-use and management practices on limed acidic and carbonate-bearing soils can fundamentally alter carbon (C) dynamics, creating an important feedback to atmospheric carbon dioxide (CO2) concentrations. Transformation of carbonates in such soils and its implication for C sequestration with climate change are largely unknown and there is much speculation about inorganic C sequestration via bicarbonates. Soil carbonate equilibrium is complicated, and all reactants and reaction products need to be accounted for fully to assess whether specific processes lead to a net removal of atmospheric CO2. Data are scarce on the estimates of CaCO3 stocks and the effect of land-use management practices on these stocks, and there is a lack of understanding on the fate of CO2 released from carbonates. We estimated carbonate stocks from four major soil types in Australia (Calcarosols, Vertosols, Kandosols and Chromosols). In >200-mm rainfall zone, which is important for Australian agriculture, the CaCO3-C stocks ranged from 60.7 to 2542 Mt at 0–0.3 m depth (dissolution zone), and from 260 to 15 660 Mt at 0–1.0 m depth. The combined CaCO3-C stocks in Vertosols, Kandosols and Chromosols were about 30% of those in Calcarosols. Total average CaCO3-C stocks in the dissolution zone represented 11–23% of the stocks present at 0–1.0 m depth, across the four soil types. These estimates provide a realistic picture of the current variation of CaCO3-C stocks in Australia while offering a baseline to estimate potential CO2 emission–sequestration through land-use changes for these soil types. In addition, we provide an overview of the uncertainties in accounting for CO2 emission from soil carbonate dissolution and major inorganic C transformations in soils as affected by land-use change and management practices, including liming of acidic soils and its secondary effects on the mobility of dissolved organic C. We also consider impacts of liming on mineralisation of the native soil C, and when these transformations should be considered a net atmospheric CO2 source or sink.
Factors mediating plastid dependency and the origins of parasitism in apicomplexans and their close relatives
Authors: Janouškovec Jan , Tikhonenkov Denis V. , Burki Fabien , Howe Alexis T. , Kolísko Martin , Mylnikov Alexander P. , Keeling Patrick J.
Published: February 2015

Apicomplexans are a major lineage of parasites, including causative agents of malaria and toxoplasmosis. How such highly adapted parasites evolved from free-living ancestors is poorly understood, particularly because they contain nonphotosynthetic plastids with which they have a complex metabolic dependency. Here, we examine the origin of apicomplexan parasitism by resolving the evolutionary distribution of several key characteristics in their closest free-living relatives, photosynthetic chromerids and predatory colpodellids. Using environmental sequence data, we describe the diversity of these apicomplexan-related lineages and select five species that represent this diversity for transcriptome sequencing. Phylogenomic analysis recovered a monophyletic lineage of chromerids and colpodellids as the sister group to apicomplexans, and a complex distribution of retention versus loss for photosynthesis, plastid genomes, and plastid organelles. Reconstructing the evolution of all plastid and cytosolic metabolic pathways related to apicomplexan plastid function revealed an ancient dependency on plastid isoprenoid biosynthesis, predating the divergence of apicomplexan and dinoflagellates. Similarly, plastid genome retention is strongly linked to the retention of two genes in the plastid genome,sufBandclpC, altogether suggesting a relatively simple model for plastid retention and loss. Lastly, we examine the broader distribution of a suite of molecular characteristics previously linked to the origins of apicomplexan parasitism and find that virtually all are present in their free-living relatives. The emergence of parasitism may not be driven by acquisition of novel components, but rather by loss and modification of the existing, conserved traits.
Three distinct ribosome assemblies modulated by translation are the building blocks of polysomes
Authors: Viero Gabriella , Lunelli Lorenzo , Passerini Andrea , Bianchini Paolo , Gilbert Robert J. , Bernabò Paola , Tebaldi Toma , Diaspro Alberto , Pederzolli Cecilia , Quattrone Alessandro
Published: February 2015

Translation is increasingly recognized as a central control layer of gene expression in eukaryotic cells. The overall organization of mRNA and ribosomes within polysomes, as well as the possible role of this organization in translation are poorly understood. Here we show that polysomes are primarily formed by three distinct classes of ribosome assemblies. We observe that these assemblies can be connected by naked RNA regions of the transcript. We show that the relative proportions of the three classes of ribosome assemblies reflect, and probably dictate, the level of translational activity. These results reveal the existence of recurrent supra-ribosomal building blocks forming polysomes and suggest the presence of unexplored translational controls embedded in the polysome structure.
Regulation of C-X-C chemokine gene expression by keratin 17 and hnRNP K in skin tumor keratinocytes
Authors: Chung Byung Min , Arutyunov Artem , Ilagan Erika , Yao Nu , Wills-Karp Marsha , Coulombe Pierre A.
Published: February 2015

High levels of the intermediate filament keratin 17 (K17) correlate with a poor prognosis for several types of epithelial tumors. However, the causal relationship and underlying mechanisms remain undefined. A recent study suggested that K17 promotes skin tumorigenesis by fostering a specific type of inflammation. We report here that K17 interacts with the RNA-binding protein hnRNP K, which has also been implicated in cancer. K17 is required for the cytoplasmic localization of hnRNP K and for its role in regulating the expression of multiple pro-inflammatory mRNAs. Among these are the CXCR3 ligands CXCL9, CXCL10, and CXCL11, which together form a signaling axis with an established role in tumorigenesis. The K17–hnRNP K partnership is regulated by the ser/thr kinase RSK and required for CXCR3-dependent tumor cell growth and invasion. These findings functionally integrate K17, hnRNP K, and gene expression along with RSK and CXCR3 signaling in a keratinocyte-autonomous axis and provide a potential basis for their implication in tumorigenesis.
CD160 is essential for NK-mediated IFN-γ production
Authors: Tu Tony C. , Brown Nicholas K. , Kim Tae-Jin , Wroblewska Joanna , Yang Xuanming , Guo Xiaohuan , Lee Seoyun Hyunji , Kumar Vinay , Lee Kyung-Mi , Fu Yang-Xin
Published: February 2015

NK-derived cytokines play important roles for natural killer (NK) function, but how the cytokines are regulated is poorly understood. CD160 is expressed on activated NK or T cells in humans but its function is unknown. We generated CD160-deficient mice to probe its function. Although CD160−/− mice showed no abnormalities in lymphocyte development, the control of NK-sensitive tumors was severely compromised in CD160−/− mice. Surprisingly, the cytotoxicity of NK cells was not impaired, but interferon-γ (IFN-γ) secretion by NK cells was markedly reduced in CD160−/− mice. Functionally targeting CD160 signaling with a soluble CD160-Ig also impaired tumor control and IFN-γ production, suggesting an active role of CD160 signaling. Using reciprocal bone marrow transfer and cell culture, we have identified the intrinsic role of CD160 on NK cells, as well as its receptor on non-NK cells, for regulating cytokine production. To demonstrate sufficiency of the CD160+ NK cell subset in controlling NK-dependent tumor growth, intratumoral transfer of the CD160+ NK fraction led to tumor regression in CD160−/− tumor-bearing mice, indicating demonstrable therapeutic potential for controlling early tumors. Therefore, CD160 is not only an important biomarker but also functionally controls cytokine production by NK cells.
Restored glial glutamate transporter EAAT2 function as a potential therapeutic approach for Alzheimer’s disease
Authors: Takahashi Kou , Kong Qiongman , Lin Yuchen , Stouffer Nathan , Schulte Delanie A. , Lai Liching , Liu Qibing , Chang Ling-Chu , Dominguez Sky , Xing Xuechao , Cuny Gregory D. , Hodgetts Kevin J. , Glicksman Marcie A. , Lin Chien-Liang Glenn
Published: February 2015

Glutamatergic systems play a critical role in cognitive functions and are known to be defective in Alzheimer’s disease (AD) patients. Previous literature has indicated that glial glutamate transporter EAAT2 plays an essential role in cognitive functions and that loss of EAAT2 protein is a common phenomenon observed in AD patients and animal models. In the current study, we investigated whether restored EAAT2 protein and function could benefit cognitive functions and pathology in APPSw,Ind mice, an animal model of AD. A transgenic mouse approach via crossing EAAT2 transgenic mice with APPSw,Ind. mice and a pharmacological approach using a novel EAAT2 translational activator, LDN/OSU-0212320, were conducted. Findings from both approaches demonstrated that restored EAAT2 protein function significantly improved cognitive functions, restored synaptic integrity, and reduced amyloid plaques. Importantly, the observed benefits were sustained one month after compound treatment cessation, suggesting that EAAT2 is a potential disease modifier with therapeutic potential for AD.
Stabilities of homothetically shrinking Yang-Mills solitons
Authors: Chen Zhengxiang , Zhang Yongbing
Published: February 2015

In this paper we introduce entropy-stability and F-stability for homothetically shrinking Yang-Mills solitons, employing entropy and the second variation of the

F

\mathcal {F}

-functional respectively. For a homothetically shrinking soliton which does not descend, we prove that entropy-stability implies F-stability. These stabilities have connections with the study of Type-I singularities of the Yang-Mills flow. Two byproducts are also included: We show that the Yang-Mills flow in dimension four cannot develop a Type-I singularity, and we obtain a gap theorem for homothetically shrinking solitons.
UNC-87 isoforms,Caenorhabditis eleganscalponin-related proteins, interact with both actin and myosin and regulate actomyosin contractility
Authors: Ono Kanako , Obinata Takashi , Yamashiro Sawako , Liu Zhongmei , Ono Shoichiro
Published: February 2015

Calponin-related proteins are widely distributed among eukaryotes and involved in signaling and cytoskeletal regulation. Calponin-like (CLIK) repeat is an actin-binding motif found in the C-termini of vertebrate calponins. Although CLIK repeats stabilize actin filaments, other functions of these actin-binding motifs are unknown. The Caenorhabditis elegans unc-87 gene encodes actin-binding proteins with seven CLIK repeats. UNC-87 stabilizes actin filaments and is essential for maintenance of sarcomeric actin filaments in striated muscle. Here we show that two UNC-87 isoforms, UNC-87A and UNC-87B, are expressed in muscle and nonmuscle cells in a tissue-specific manner by two independent promoters and exhibit quantitatively different effects on both actin and myosin. Both UNC-87A and UNC-87B have seven CLIK repeats, but UNC-87A has an extra N-terminal extension of ∼190 amino acids. Both UNC-87 isoforms bind to actin filaments and myosin to induce ATP-resistant actomyosin bundles and inhibit actomyosin motility. UNC-87A with an N-terminal extension binds to actin and myosin more strongly than UNC-87B. UNC-87B is associated with actin filaments in nonstriated muscle in the somatic gonad, and an unc-87 mutation causes its excessive contraction, which is dependent on myosin. These results strongly suggest that proteins with CLIK repeats function as a negative regulator of actomyosin contractility.
Ritual
Authors: Stephenson Barry
Published: February 2015

Ritual is part of what it means to be human. It defines and enriches culture, but what is ritual? What are the various kinds of ritual? Is ritual tradition bound and conservative or innovative and transformational? Ritual: A Very Short Introduction describes a number of specific rites and explores ritual from theoretical and historical perspectives. It focuses on the places where ritual touches everyday life; shows how ritual is an important vehicle for group and identity formation; how it generates and transmits beliefs and values; how it can be used to exploit and oppress; and how it has served as a touchstone for thinking about cultural origins and historical change.
Introduction
Authors: Stephenson Barry
Published: February 2015

The ‘Introduction’ asks what is ritual? Is ritual useful? What are the various kinds of ritual? It suggests that to think about ritual is to reflect on human nature, sociality, and culture. It is also to explore ritual's place, power, and potential in our lives and our society. Ritual includes both religious and nonreligious rites, the traditional and the new, the prescribed and the improvised, the human and nonhuman, and rubs up against a number of other cultural domains, such as play, games, performance, and theater. If ritual is action, it is also an idea, something we think with, and our exploration will move back and forth between these two dimensions.
1. Ritualization
Authors: Stephenson Barry
Published: February 2015

‘Ritualization’ considers one of the cornerstones of ritual studies—ritualization. It begins with ethology, the study of animal behaviour and goes on to discuss ritualization theory and how this has shaped new attitudes toward the rites we humans perform. Ethology postulates that ritualization is a selective process that allows for the enhanced communication of evolutionary advantageous information and emotional states. What is gained through a biological approach to ritual? What does ethology contribute to our understanding of human ritual, and what are its limitations? Ritual is a window toward our biological or animal being and our cultural being; it is also the point at which these dimensions intersect, mingle, and influence one another.
2. Ritual and the origins of culture
Authors: Stephenson Barry
Published: February 2015

From an ethological perspective, ritual must have been present at the beginnings of humanity and ritualization played an adaptive role in the course of both biological and cultural evolution. What was the role and function of ritual in the earliest period of cultural evolution? ‘Ritual and the origins of culture’ considers the diverse and speculative scholarly answers: shamanic trance and the emergence of advanced cognitive abilities; the construction of ritual sites as an expression of existential needs and interests, leading to the growth of large-scale, settled society and the separation of the sacred and profane; or sacrifice as a necessary mechanism to control violence and with it the birth of the sacred and religious systems.
4. Ritual and transformation
Authors: Stephenson Barry
Published: February 2015

There are many rites that traffic in symbols and processes of transformation: healing rites, funerary rites, magic, sacrifice, rites of inversion, and rites of passage. Ritual theorists approach ritual as not merely decorous or expressive, but of real consequence and practical efficacy. If ritual is efficacious, just how does it accomplish its work? Is ritual really capable of effecting transformation? ‘Ritual and transformation’ explores these questions by focussing on two categories of ritual commonly associated with change and transformation—initiation and magic. It also considers ritual criticism as developed by Ronald Grimes and others to qualitatively measure and ethically evaluate the kinds of changes taking place in and through ritual.