bluuebunny/crossref_metadata_2025 huggingface dataset:
Identifying misbehaving models using baseline climate variance
Authors: Schultz Colin
Published: June 2011

The majority of projections made using general circulation models (GCMs) are conducted to help tease out the effects on a region, or on the climate system as a whole, of changing climate dynamics. Sun et al., however, used model runs from 20 different coupled atmosphere‐ocean GCMs to try to understand a different aspect of climate projections: how bias correction, model selection, and other statistical techniques might affect the estimated outcomes. As a case study, the authors focused on predicting the potential change in precipitation for the Murray‐Darling Basin (MDB), a 1‐million‐square‐kilometer area in southeastern Australia that suffered a recent decade of drought that left many wondering about the potential impacts of climate change on this important agricultural region. The authors first compared the precipitation predictions made by the models with 107 years of observations, and they then made bias corrections to adjust the model projections to have the same statistical properties as the observations. They found that while the spread of the projected values was reduced, the average precipitation projection for the end of the 21st century barely changed. Further, the authors determined that interannual variations in precipitation for the MDB could be explained by random chance, where the precipitation in a given year was independent of that in previous years.
Building an atlas of Arctic climate dynamics
Authors: Schultz Colin
Published: June 2011

The oceans and atmosphere act as a giant heat mixer. However, they do not spread energy evenly across the planet—the overall effect is a net poleward transfer of energy. While it is known that this energy is predominantly moved by traveling air packets and heat exchange between different media, what is less well understood is how these mechanisms interact over small scales to produce regional patterns of temperature. Understanding these interactions is particularly pressing in the Arctic, where an amplified response to greenhouse gas—induced global warming could potentially skew the relationship between these mechanisms, thereby triggering serious changes in climate dynamics. To sort out the primary forces dictating regional Arctic temperature anomalies and to determine if they are changing with global warming, Serreze et al. compiled records of sea surface temperature, sea ice extent, wind speed and direction, atmospheric temperature, and snow cover stretching back to 1979. The researchers determined that wind direction is overall one of the most powerful dictators of local weather, being associated with temperature swings of up to 10°C for some areas. The authors also found that if wind passes over regions affected by spikes in sea surface temperature or dips in sea ice cover, these anomalies could be spread to surrounding areas. (Journal of Geophysical Research‐Atmospheres, doi:10.1029/2010JD015127, 2011)
Acute changes in temperature or oxygen availability induce ROS fluctuations inDaphnia magnalinked with fluctuations of reduced and oxidized glutathione, catalase activity and gene (haemoglobin) expression
Authors: Becker Dörthe , Brinkmann Benjamin F. , Zeis Bettina , Paul Rüdiger J.
Published: June 2011

Background information. ROS (reactive oxygen species) as well as components of the antioxidant redox systems may act as signals. To link acute environmental change with gene expression, changes in ROS and GSH/GSSG (reduced/oxidized glutathione) level were measured upon acute changes in temperature or oxygen availability in the aquatic key speciesDaphnia magnatogether with HIF‐1 (hypoxia‐inducible factor 1)‐mediated Hb (haemoglobin) expression.

Results. Acute exposures to 30°C or hypoxia, which induced tissue hypoxia (and possibly elevated mitochondrial ROS production), caused resembling fluctuations of ROS and GSH levels, with frequency and number of peaks increasing and their delay decreasing with the magnitude of environmental change (size of tissue hypoxia). Acute hyperoxia induced an initial decrease in ROS level. Evidence is also provided for the promoting effects of ROS on catalase activity. A signalling function of the ROS fluctuations upon acute changes in temperature was found in the case of Hb, the expression of which is known to respond to temperature changes, by detecting corresponding time courses of both transcription and protein formation.

Conclusion. ROS‐dependent signalling was affected by changes in temperature or oxygen availability. Feedback interactions between ROS and the glutathione redox system, possibly driven by elevated mitochondrial ROS production, likely contributed to the appearance of the ROS and GSH fluctuations upon acute environmental change. Fluctuating ROS levels, which reflect for the magnitude of environmental change, could be a way to transfer information on ROS production to subsequent processes (gene expression) while avoiding too‐high and damaging ROS levels.
Surface plasmon enhanced absorption dynamics of regioregular poly(3-hexylthiophene)
Authors: Wang Hai , Wang Hai-Yu , Gao Bing-Rong , Jiang Ying , Yang Zhi-Yong , Hao Ya-Wei , Chen Qi-Dai , Du Xiao-Bo , Sun Hong-Bo
Published: June 2011

An increased absorption of regioregular poly(3-hexylthiophene) due to surface plasmons (SPs) has been studied by steady state fluorescence spectra measurements and femtosecond transient absorption (TA) technique. The SPs were excited by periodic Ag grating structures transferred from the photoresist gratings which were fabricated by two-beam laser interference. The steady state fluorescence measurements show a maximum enhanced fluorecence of about 16 times larger arising from the absorption enhancement. Further investigation by TA technique reveals that the yield of the polaron pairs on Ag gratings significantly increase, much bigger than that of the pure sample, which also confirms the enhanced absorption efficiency as resulting from the excited SPs.
In situ analysis of elemental depth distributions in thin films by combined evaluation of synchrotron x-ray fluorescence and diffraction
Authors: Mainz R. , Klenk R.
Published: June 2011

In this work we present a method for the in situ analysis of elemental depth distributions in thin films using a combined evaluation of synchrotron x-ray fluorescence and energy-dispersive x-ray diffraction signals. We recorded diffraction and fluorescence signals simultaneously during the reactive annealing of thin films. By means of the observed diffraction signals, the time evolution of phases in the thin films during the annealing processes can be determined. We utilized this phase information to parameterize the depth distributions of the elements in the films. The time-dependent fluorescence signals were then taken to determine the parameters representing the parameterized depth distributions. For this latter step, we numerically calculated the fluorescence intensities for a given set of depth distributions. These calculations handle polychromatic excitation and arbitrary functions of depth distributions and take into account primary and secondary fluorescence. Influences of lateral non-uniformities of the films, as well as the accuracy limits of the method, are investigated. We apply the introduced method to analyze the evolution of elemental depth distributions and to quantify the kinetic parameters during a synthesis process of CuInS2 thin films via the reactive annealing of Cu–In precursors in a sulfur atmosphere.
Perpendicular magnetization of CoFeB on single-crystal MgO
Authors: Lee Kangho , Sapan Jonathan J. , Kang Seung H. , Fullerton Eric E.
Published: June 2011

CoFeB films deposited on single-crystal MgO(100) exhibit significantly reduced out-of-plane demagnetization fields after magnetic annealing in the film plane, resulting in perpendicular magnetization for a 15 Å CoFeB film. The perpendicular magnetic anisotropy can be enhanced further by inserting a thin Ru capping layer on top of CoFeB, resulting in perpendicular magnetization in even thicker CoFeB films.
Quantifying the defect-dominated size effect of fracture strain in single crystalline ZnO nanowires
Authors: He Mo-Rigen , Xiao Pan , Zhao Jiong , Dai Sheng , Ke Fujiu , Zhu Jing
Published: June 2011

The diameter (D) dependence of fracture strains in [0001]-oriented single crystalline ZnO nanowires (NWs) with D ranging from 18 to 114 nm is experimentally revealed via in situ uniaxial tension and is well understood based on an analytical model developed by combining molecular dynamics simulations with fracture mechanics theories. We show that the scattered fracture strains are dominated by the effective quantities of atomic vacancies, and their lower bound follows a power-form scaling law, resembling the Griffith-type behavior of single critical defects with diameter-dependent sizes, when D is larger than a critical DC. In addition, theoretical strength is expected in NWs with D < DC. Our studies provide a simple, but basic, understanding for the size effect of strengths in single crystalline NWs.
Dynamics of laser-induced surface phase explosion in silicon
Authors: Kudryashov Sergey I. , Paul Stanley , Lyon Kevin , Allen Susan D.
Published: June 2011

Time-resolved ultrasonic studies revealed a second, delayed ablative pressure pulse after the first primary plasma pressure pulse in a silicon wafer irradiated by a UV nanosecond laser. The intensity-dependent delay time for the second pulse indicates the existence of a corresponding intensity-dependent homogeneous vapor bubble nucleation time in the superheated molten silicon prior to its phase explosion and ablative removal, since the integral pressure correlates with the ablation rate. A transient hot ablative plasma with calculated peak temperature ∼30–90 eV and pressure ∼20–110 GPa is suggested to superheat the bulk silicon via short-wavelength recombination and Bremsstrahlung emission.
Generalized phonon-assisted Zener tunneling in indirect semiconductors with non-uniform electric fields: A rigorous approach
Authors: Vandenberghe William , Sorée Bart , Magnus Wim , Fischetti Massimo V.
Published: June 2011

A general framework to calculate the Zener current in an indirect semiconductor with an externally applied potential is provided. Assuming a parabolic valence and conduction band dispersion, the semiconductor is in equilibrium in the presence of the external field as long as the electron-phonon interaction is absent. The linear response to the electron-phonon interaction results in a non-equilibrium system. The Zener tunneling current is calculated from the number of electrons making the transition from valence to conduction band per unit time. A convenient expression based on the single particle spectral functions is provided, enabling the evaluation of the Zener tunneling current under any three-dimensional potential profile. For a one-dimensional potential profile an analytical expression is obtained for the current in a bulk semiconductor, a semiconductor under uniform field, and a semiconductor under a non-uniform field using the WKB (Wentzel–Kramers–Brillouin) approximation. The obtained results agree with the Kane result in the low field limit. A numerical example for abrupt p-n diodes with different doping concentrations is given, from which it can be seen that the uniform field model is a better approximation than the WKB model, but a direct numerical treatment is required for low bias conditions.
On the implementation of computed laminography using synchrotron radiation
Authors: Helfen L. , Myagotin A. , Mikulík P. , Pernot P. , Voropaev A. , Elyyan M. , Di Michiel M. , Baruchel J. , Baumbach T.
Published: June 2011

Hard x rays from a synchrotron source are used in this implementation of computed laminography for three-dimensional (3D) imaging of flat, laterally extended objects. Due to outstanding properties of synchrotron light, high spatial resolution down to the micrometer scale can be attained, even for specimens having lateral dimensions of several decimeters. Operating either with a monochromatic or with a white synchrotron beam, the method can be optimized to attain high sensitivity or considerable inspection throughput in synchrotron user and small-batch industrial experiments. The article describes the details of experimental setups, alignment procedures, and the underlying reconstruction principles. Imaging of interconnections in flip-chip and wire-bonded devices illustrates the peculiarities of the method compared to its alternatives and demonstrates the wide application potential for the 3D inspection and quality assessment in microsystem technology.
Formation of metallic nanoclusters in oxygen deficient indium tin oxide films
Authors: Perrière J. , Hebert C. , Petitmangin A. , Portier X. , Seiler W. , Nistor M.
Published: June 2011

The composition, structure, microstructure, and properties of indium tin oxide films grown by pulsed laser deposition at room temperature and under vacuum were studied. The films are highly nonstoichiometric, with about 20% oxygen deficiency, and present a semiconductor behavior between 300 and 15 K, followed by a superconducting transition at about 7 K related to the presence of In or In-Sn nanoclusters embedded in a stoichiometric indium tin oxide matrix, i.e., nanocomposite films are formed by the phase separation of oxygen deficient metastable indium tin oxide. The solid-liquid and liquid-solid phase transitions of the metallic nanoclusters were evidenced by resistivity measurements in the 300 to 450 K range. The films grown at room temperature are partially crystallized. Actually, stoichiometric indium tin oxide crystallites are observed in the as grown films. After thermal treatment (<450 K), both stoichiometric indium tin oxide crystallites and the tetragonal phase of the metallic In are observed in the nanocomposite films. The size of nanoclusters (from 5 to 30 nm), which depends on the thermal treatments and crystallization, and the microstructure of the nanocomposite films were confirmed by HRTEM measurements.
Regrowth of oxide-embedded amorphous silicon studied with molecular dynamics
Authors: Lampin E. , Krzeminski C.
Published: June 2011

Classical molecular dynamics simulations are applied to the study of amorphous silicon regrowth in a nanodevice. A simplified atomistic amorphous nanostructure presenting the main features of a FinFET device is designed. A thermal treatment is used to simulate the annealing of the atomic model. The structure after annealing is very close to what observed experimentally, with perfect crystal near the silicon seed, an intermediate crystalline layer presenting [111] twins, and an upper terminal region of polysilicon. The comparison with 2D system suggests surface proximity effects that impact the probability to form grains and twins. As a consequence, it seems like the solid phase epitaxy was arrested in the nanostructure.
Size-dependent magnetic moments in ultrafine diamagnetic systems
Authors: Yang J. Y. , Sun Y. , He L. , Xiong C. M. , Dou R. F. , Nie J. C.
Published: June 2011

Recently, unusual magnetic properties were found experimentally in otherwise diamagnetic nanoparticles. Our experiments and analysis revealed that a universal expression can describe the size-dependent magnetic moments in ultrafine diamagnetic systems, including Au, Pd, and HfO2 nanoparticles. A model was presented to explain the observed phenomenon. It suggested that the up and down spins in ultrafine diamagnetic systems are spatially separated and form asymmetric spin-singlet pairs. The correlation lengths of the spin-singlet pairs in Au, Pd, and HfO2 nanoparticles were estimated to be about 1.65, 13, and 4.4 nm, respectively. On the basis of this model, we explain (a) the origin and the size dependence of magnetic moments in diamagnetic nanoparticles, and (b) the origin of the extremely large anisotropy in diamagnetic nanoparticles.
Electrical conductivity and asymmetric material changes upon irradiation of Mg-doped lithium niobate crystals with low-mass, high-energy ions
Authors: Jentjens L. , Raeth N. L. , Peithmann K. , Maier K.
Published: June 2011

Radiation damage in magnesium-doped lithium niobate crystals, created by low-mass, high-energy ions which have transmitted the entire crystal thickness, leads to an enhanced electrical dark conductivity as well as an enhanced photoconductivity. Experimental results on the electrical properties after ion exposure are given, and an asymmetric dependence of the conductivity as well as refractive index changes on the irradiation geometry with respect to the ferroelectric axis is revealed.
Collisions of ageostrophic modons and formation of new types of coherent structures in rotating shallow water model
Authors: Lahaye Noé , Zeitlin Vladimir
Published: June 2011

We study collisions of recently discovered ageostrophic modons in rotating shallow water model at different values of impact parameter and find that two new types of coherent vortex structures may be formed during this process: “nonlinear” modons, i.e., coherent dipoles with essentially nonlinear scatter plot and coherent tripoles. Both are known for incompressible 2D Euler equations, but were not reported in the “compressible” shallow water model. Inelastic scattering with strong filamentation and shearing is also possible. Surprisingly, the strongly nonlinear process of coherent structure formation leads to almost no emission of inertia-gravity waves.
Direct observation of sub-threshold field emission from silicon nanomembranes
Authors: Qin Hua , Tan Renbing , Park Jonghoo , Kim Hyun-Seok , Blick Robert H.
Published: June 2011

Excited by an energetic electron beam, field enhanced electron emission from a silicon nanomembrane is examined by using a local current probe. The experiments reveal clear transitions from conventional secondary electron emission (SEE) to sub-threshold field electron emission (SFE) and then to conventional field electron emission (FEE). An electron yield of more than 104 is obtained and a model of sub-threshold emission is verified. Ultra sensitive charge/particle detectors could be realized by implementing sub-threshold field emission in nano scale structures, where electron excitations occur within the screen depth of surface electric field.
Controllable rectifying performance in a C60 molecular device with asymmetric electrodes
Authors: Fan Zhi-Qiang , Chen Ke-Qiu
Published: June 2011

By using nonequilibrium Green’s functions in combination with the density-functional theory, we investigate the current-voltage character of a single C60 molecule sandwiched between Au electrode and carbon nanotube electrode theoretically. The calculated results show that the asymmetric electrodes connecting is of significant influence on the transport properties. By adjusting the matching of orbitals around the Fermi level among the two electrodes and the molecule, the rectifying behavior of the device can be realized and the rectification ratio can be modulated.
Optical study of hydrogen-irradiated GaAsN/GaAs heterostructures
Authors: Geddo M. , Patrini M. , Guizzetti G. , Galli M. , Trotta R. , Polimeni A. , Capizzi M. , Martelli F. , Rubini S.
Published: June 2011

The effect of hydrogen irradiation on the optical properties of GaAs1−xNx/GaAs heterostructures was investigated using photoreflectance and reflectance techniques. Systematic measurements performed on both as-grown and hydrogenated samples for N-concentrations ranging from 0.0% to 3.5% and for H-implanted doses from 3 × 1018 to 6 × 1018 ions/cm2 have shown that (a) the H-induced widening of the energy gap is accompanied by a decrease of the refractive index of the H-treated samples with respect to the as-grown ones, resulting in an index mismatch that can be as large as 2% in the subgap spectral region; and (b) the presence of compressive strain in fully passivated GaAsN determines a decrease of the refractive index even below that of GaAs that can be eliminated via moderate thermal annealing. These findings are promising for the development of heterostructures with planar geometry, in which the simultaneous confinement of both carriers and photons, even on a nanometric scale, can be obtained in a single step process.
Thermodynamic factors limiting the preservation of aromaticity of adsorbed organic compounds on Si(100): Example of the pyridine
Authors: Coustel R. , Carniato S. , Boureau G.
Published: June 2011

Using pyridine as an example, a thermodynamic analysis of the low temperatures adsorption of aromatic organic molecules with a N atom on the Si(100) surface is presented. This study is restricted to the case of an equilibrium with the gas phase. Dative attachment which is the only way to preserve aromaticity is the more stable form of adsorbed pyridine in dilute solutions at low temperatures. Two factors limit the domain of stability of dative attachment: repulsive interactions between dative bonds prevent them from being present in concentrated solutions while aromaticity contributes to a decrease in the entropy, which explains the vanishing of dative bonds at high temperatures even in dilute solutions.
Voltage-controlled active mid-infrared plasmonic devices
Authors: Anglin K. , Ribaudo T. , Adams D. C. , Qian X. , Goodhue W. D. , Dooley S. , Shaner E. A. , Wasserman D.
Published: June 2011

We demonstrate active voltage-controlled spectral tuning of mid-infrared plasmonic structures. Extraordinary optical transmission gratings were fabricated on n-doped GaAs epilayers with a HfO2 gate dielectric between the grating and the doped semiconductor. The permittivity of the GaAs was tuned by depleting charge carriers below the top grating gate upon the application of a reverse bias to the gate. Devices were characterized both electrically and optically, and resonant transmission peak spectral and transmitted intensity shifts were achieved. Possible applications for, as well as the limitations of, the demonstrated technology are discussed.
A remote scanning Raman spectrometer for in situ measurements of works of art
Authors: Brambilla Alex , Osticioli Iacopo , Nevin Austin , Comelli Daniela , D'Andrea Cosimo , Lofrumento Cristiana , Valentini Gianluca , Cubeddu Rinaldo
Published: June 2011

In conservation science, one of the main concerns is to extract information from an artistic surface without damaging it. Raman spectroscopy has emerged in recent years as a reliable tool for the non-destructive analysis of a wide range of inorganic and organic materials in works of art and archaeological objects. Nevertheless, the technique is still mainly limited to the analysis of micro-samples taken from artistic surfaces. The development of an instrument able to perform non-contact analysis of an area of a few square centimeters aims to further increase the employment of this technique. This paper describes the development of a prototype Raman scanning spectrometer based on a diode laser, a 2D scanning mirror stage and a custom optical system, which can map a surface of 6 cm in diameter at a working distance of 20 cm. The device exhibits collecting optics with a depth of field close to 6 cm, which makes the Raman system suitable for the analysis of non-flat surfaces and three-dimensional objects. In addition, the overall dimensions and weight of the instrument have been limited in order to make the device transportable and, in principle, usable for in situ measurements. Details on the design of the device, with particular emphasis on the collecting optical system, and on results of the characterization tests carried out to assess its performances are reported. Finally, an example of an application involving the identification of pigments from a model painting is presented.
Selective-area vapor-liquid-solid growth of tunable InAsP quantum dots in nanowires
Authors: Dalacu Dan , Mnaymneh Khaled , Wu Xiaohua , Lapointe Jean , Aers Geof C. , Poole Philip J. , Williams Robin L.
Published: June 2011

A process is described where the position, size, and cladding of an InP nanowire with an embedded InAsP quantum dot are determined by design through lithography, processing, and growth. The vapor-liquid-solid growth mode on a patterned substrate is used to grow the InP core and defines the quantum dot size to better than ±2 nm while selective-area growth is used to define the cladding thickness. The clad nanowires emit efficiently in the range λ=0.95–1.15 μm. Photoluminescence measurements are used to quantify the dependence of the excitonic energy level structure on quantum dot size for diameters 10–40 nm.
Initial value representation for the SU(n) semiclassical propagator
Authors: Viscondi Thiago F. , de Aguiar Marcus A. M.
Published: June 2011

The semiclassical propagator in the representation of SU(n) coherent states is characterized by isolated classical trajectories subjected to boundary conditions in a doubled phase space. In this paper, we recast this expression in terms of an integral over a set of initial-valued trajectories. These trajectories are monitored by a filter that collects only the appropriate contributions to the semiclassical approximation. This framework is suitable for the study of bosonic dynamics in n modes with fixed total number of particles. We exemplify the method for a Bose-Einstein condensate trapped in a triple-well potential, providing a detailed discussion on the accuracy and efficiency of the procedure.
Determination of the subcell photovoltage in multijunction solar cells via voltage-dependent capacitance analysis
Authors: Hoheisel R. , Schachtner M. , Stämmler E. , Bett A. W.
Published: June 2011

The letter describes a method for determining the photovoltage, i.e., the quasifermi level splitting at open-circuit conditions, associated with each subcell in a series connected multijunction solar cell structure by voltage-dependent capacitance analysis. Experimental verification and accuracy analysis of subcell photovoltage determination is provided for a 6-tuple AlGaInP/GaInP/AlGaInAs/GaInAs/GaInNAs/Ge solar cell device.
Enhanced magneto-optical oscillations from two-dimensional hole-gases in the presence of Mn ions
Authors: Gazoto A. L. , Brasil M. J. S. P. , Iikawa F. , Brum J. A. , Ribeiro E. , Danilov Yu. A. , Vikhrova O. V. , Zvonkov B. N.
Published: June 2011

We investigated the effects of nearby Mn ions on the optical properties of two-dimensional hole-gases confined in InGaAs/GaAs quantum wells. We observed energy oscillations on both the averaged emission and the spin-splitting energies, whereas the first one presents maxima at all integer filling factors, and the second one, solely at odd-filling factors. The strength of the oscillations clearly increases with the Mn concentration. Furthermore, considering the relatively low-mobility of our structures, the oscillations are surprisingly strong and robust, persisting up to relatively high temperatures and excitation intensities.
Vibronic effects on the 1t1 → 3s Rydberg excitation in CF4 induced by electron impact
Authors: Watanabe Noboru , Suzuki Daisuke , Takahashi Masahiko
Published: June 2011

We report a theoretical study of vibronic effects on the 1t1 → 3s Rydberg excitation in CF4 induced by electron impact. The generalized oscillator strength for the excitation has been calculated using theoretical wave functions at the equation-of-motion coupled cluster singles and doubles level. In the calculation vibronic effects have been taken into account by evaluating the electronic transition moment along the individual normal coordinates. The present calculation successfully reproduces our recent experimental result [N. Watanabe, D. Suzuki, and M. Takahashi, J. Chem. Phys. 134, 064307 (2011)]10.1063/1.3549135 over the full momentum transfer region studied. By examining contributions from individual normal modes, the asymmetric stretching mode is found to play a leading role in the 1t1 → 3s transition at small momentum transfer.
Experiments on wireless power transfer with metamaterials
Authors: Wang Bingnan , Teo Koon Hoo , Nishino Tamotsu , Yerazunis William , Barnwell John , Zhang Jinyun
Published: June 2011

In this letter, we propose the use of metamaterials to enhance the evanescent wave coupling and improve the transfer efficiency of a wireless power transfer system based on coupled resonators. A magnetic metamaterial is designed and built for a wireless power transfer system. We show with measurement results that the power transfer efficiency of the system can be improved significantly by the metamaterial. We also show that the fabricated system can be used to transfer power wirelessly to a 40 W light bulb.
Significant substitution effects in dipolar and non-dipolar supercritical fluids
Authors: Kajiya Daisuke , Saitow Ken-ichi
Published: June 2011

Vibrational Raman spectra of C=C stretching modes of ethylene derivates (cis-C2H2Cl2, cis-stilbene, and trans-stilbene) were measured in supercritical fluids along an isotherm as functions of their densities. The substitution effect of the Raman shift is so significant that a difference among three solutes can be 20 times and is observed similarly in dipolar (CHF3) and non-dipolar (CO2) fluids. In particular, the shifts of trans-stilbene were enormously large among all systems for studies of vibrational spectroscopies of supercritical fluids and were equivalent to those of typical hydrogen-bonded fluids. Such large shifts arising from the significant attractive energy between solute and solvent molecules were attributed to a site-selective solvation around a phenyl group, which was driven by a dispersion force in the absence of steric hindrance. We found that the absence of steric hindrance causes the significant local density augmentation. To the best of our knowledge, Raman experiments and their theoretical analysis are the first ones quantifying how the difference of steric hindrance produces solvation structures in solution as well as supercritical solutions.
Hydrophobic interactions with coarse-grained model for water
Authors: Egorov S. A.
Published: June 2011

Integral equation theory is applied to a coarse-grained model of water to study potential of mean force between hydrophobic solutes. Theory is shown to be in good agreement with the available simulation data for methane-methane and fullerene-fullerene potential of mean force in water; the potential of mean force is also decomposed into its entropic and enthalpic contributions. Mode coupling theory is employed to compute self-diffusion coefficient of water as well as diffusion coefficient of a dilute hydrophobic solute; good agreement with molecular dynamics simulation results is found.
Study of variations of the carrier recombination and charge transport parameters during proton irradiation of silicon pin diode structures
Authors: Gaubas E. , Čeponis T. , Vaitkus J. , Raisanen J.
Published: June 2011

Techniques for the remote and in situ control of carrier recombination and drift parameters during proton irradiation are presented. The measurement and evaluation of the carrier recombination and drift-diffusion characteristics are based on simultaneous analysis of microwave probed photoconductivity transients and of the induced charge collection current transients in diodes with applied electric field during the proton exposure.
2006 Southern brown bandicoots Isoodon obesulus obesulus in Belair National Park.
Authors: Sanderson K. J. , Kraehenbuehl J.
Published: June 2011

A population of southern brown bandicoots (Isoodon obesulus obesulus) in Belair National Park (NP) and neighbouring areas was studied from 1995 to 2002. From 1997 to 2002, 181 bandicoots (91 females, 89 males, one unknown) were microchipped. Many animals were captured only once or twice, but data from a few animals showed that bandicoots may live up to four years. Breeding occurred year round, with a mean litter size from 33 litters of 1.8. Bandicoots were trapped close to water courses in areas with thick ground cover. Black rats (Rattus rattus) were active nocturnally in all areas of Belair NP which were trapped, and may be in competition with bandicoots for food and shelter resources. Bandicoots have recently been seen in north-western areas of Belair NP where they have not been seen in years. This expansion of their distribution in the park may be related to a translocation to this area in 1998 and a fox control program which has been carried out since 1988.
Using ecological studies to understand the conservation needs of the squirrel glider in Brisbane?s urban forest-remnants.
Authors: Goldingay R. L. , Sharpe D. J. , Beyer G. L. , Dobson M.
Published: June 2011

This paper provides an overview of our current ecological research on squirrel gliders (Petaurus norfolcensis) living in forest-remnants within an urban matrix in south-east Queensland. We have conducted population censuses and behavioural observations primarily in one 60-ha remnant. The number of tagged gliders (minimum number known alive) in this remnant varied from 75 in 2002 when flowering trees were abundant, to 33 the following year when flowering was poor. Poor flowering led to a delay in breeding and a decline in the probability of glider survival. Feeding observations on gliders in the year of abundant flowering revealed that almost 50% of the diet was comprised of nectar and pollen derived from 10 tree species. A more detailed focus on flowering and its influence on population dynamics at several sites would be of considerable value in understanding the population ecology of this species. We assessed the viability of the subpopulations of P. norfolcensis distributed across the various remnants to allow identification of management actions that may improve viability. Viability analyses under various scenarios suggest that our focal metapopulation will have a high likelihood of extinction within the next 100 years. Predictions of population viability are sensitive to changes in life history parameter estimates. Thus, current field-work has been directed by the need for more precise empirical values. The remnants containing our metapopulation need to be functionally linked to larger nearby remnants to enable glider dispersal among sites. We need a better understanding of glider dispersal behaviour and how permeable the urban matrix might be for P. norfolcensis. Arterial roads and freeways sever connections between many remnants, requiring novel approaches to corridor provision. Future research should examine how habitat quality of the remnants changes over time due to tree die-back and wind-throw. We are investigating the potential role of nest boxes to facilitate glider dispersal and to supplement the availability of den trees. The findings of our studies should contribute to a greater understanding of the general conservation requirements of P. norfolcensis.
The protocols for koala research using radio-collars: a review based on its application in a tall coastal forest in New South Wales and the implications for future research.
Authors: Radford S. L. , McKee J. , Goldingay R. L. , Kavanagh R. P.
Published: June 2011

In 1996, guidelines were produced for capture and radio-tracking protocols for koala (Phascolarctos cinereus) research within New South Wales (NSW). An integrated project commenced in 1998 to examine P. cinereus ecology and health status in Pine Creek State Forest. This project utilised intensive clinical and pathological assessment protocols on captured P. cinereus in combination with radio-tracking and ecological investigations. The methods used in this project were referred to the NSW Koala Research Committee (KRC) for review in mid 1999 due to the political profile of the study area. The KRC assessed the project protocols and reviewed the original guidelines incorporating some of the protocols used in the Pine Creek project. The outcome is a new set of protocols for P. cinereus research within NSW which are more explicit and restrictive than those applied to P. cinereus research elsewhere or to research on other species. In their current form the new guidelines require a substantial investment in time, equipment, personnel and finance; factors that may deter or restrict future, comprehensive ecological research on P. cinereus populations. They inadequately provide for some practices we believe important in minimising the invasiveness of P. cinereus capture. We propose amendments to the guidelines in the areas of personnel required, behavioural assessment, capture methods, processing safety and tracking frequency. We suggest that these amendments will render the guidelines more accessible to a broader range of projects, and easier to apply under field conditions while preserving the intent to maintain P. cinereus welfare and research best practice.
A comparison of three hair-tube types for the detection of the spotted-tailed quoll Dasyurus maculatus in south-eastern New South Wales.
Authors: Nelson J. L.
Published: June 2011

The effectiveness of three different hair-tube designs at detecting the rare and cryptic forest-dependent spotted-tailed quoll Dasyurus maculatus was investigated in two trials conducted across 60 sites in an area known to be inhabited by the species. During the two trials D. maculatus was detected at a total of 14 sites. While the three hair-tube types trialed all successfully detected the species, the Faunatech hair-funnel, a hair-tube manufactured from plastic moulded into a half funnel, detected the species from the greatest number of sites and accounted for the greatest proportion of records. This hair-tube type was found to provide the most effective tool for determining the presence of D. maculatus in the typically wet environment of the study area.
An extension to the known distribution of the squirrel glider Petaurus norfolcensis in Australia.
Authors: Malekian M. , Cooper S. J. B. , Carthew S. M.
Published: June 2011

In South Australia the squirrel glider (Petaurus norfolcensis) was only known from one museum specimen from Bordertown collected in 1939. During a genetic study of Petaurus breviceps, using nucleotide sequence variation in mitochondrial DNA, two additional museum specimens collected near Bordertown, were identified as P. norfolcensis and recent field investigations in the area provided two additional specimens. The nearest locality for P. norfolcensis is the eastern side of the Grampians, several hundred kilometers east.
MR imaging of brain morphology, vascularisation and encephalization in the koala.
Authors: Taylor J. , Brown G. , De Miguel C. , Henneberg M. , Rühli F. J.
Published: June 2011

The ratio of brain volume to cranial volume of Phascolarctos cinereus has been reported to be low (60% encephalization) compared to other marsupials and eutherians. This MRI study indicates a substantial difference between the living P. cinereus brain (83% - 90% encephalization) and ones of cadaver specimens. This highlights the importance of in vivo morphological studies.
Historical records of the eastern grey kangaroo Macropus giganteus on Cape York Peninsula: clues to a postulated range extension.
Authors: Winter J. W.
Published: June 2011

Historical records of Macropus giganteus on Cape York Peninsula indicate a low population rather than an expanding population.
National Health and Hospital Reform Commission final report and patient-centred suggestions for reform
Authors: Jowsey Tanisha , Yen Laurann , Wells Robert , Leeder Stephen
Published: June 2011

The final report of the National Health and Hospital Reform Commission (NHHRC) called for a strengthened consumer voice and empowerment. This has salience for the development of health policy concerning chronic illnesses. This paper compares the recommendations for chronic illness care made in the NHHRC final report with suggestions made by people with chronic illness and family carers of people with chronic illness in a recent Australian study. Sixty-six participants were interviewed in a qualitative research project of the Serious and Continuing Illness Policy and Practice Study (SCIPPS). Participants were people with type II diabetes mellitus, chronic obstructive pulmonary disease or chronic heart failure. Family carers were also interviewed. Content analysis was undertaken and participants’ recommendations for improving care were compared with those proposed in the NHHRC final report. Many suggestions from the participants of the SCIPPS qualitative research project appeared in the NHHRC final report, including the need to improve care coordination, health literacy and the experience of Indigenous Australians. The research project also identified important issues of family carers, immigrants and people with multiple illnesses, which were not addressed in the NHHRC final report. More specific attention is needed in health reform to improve the experience of family carers, Indigenous peoples, immigrants to Australia and people with multiple illnesses. To align more closely with their needs, health reform must be explicitly informed by the voices of people with chronic illness and their family carers. The NHHRC recommendations must be supplemented with proposals that address the needs of these people for support and the problems associated with poor care coordination.
'Perfect skin', the media and patients with skin disease: a qualitative study of patients with acne, psoriasis and atopic eczema
Authors: Magin Parker , Adams Jon , Heading Gaynor , Pond Dimity
Published: June 2011

The relationship of skin disease with societal ideals of beauty, and the role of the media in this relationship, has not previously been researched. The overall objective of this study was to explore the psychological effects of skin disease. The theme of the ideal of perfect skin and the role of the media in generating this ideal arose via an inductive study methodology and was explored in the context of respondents’ psychological morbidity. A qualitative study, 62 semi-structured interviews were conducted with respondents with acne, eczema or psoriasis recruited from both general practice and specialist dermatology practice in an Australian regional city. Interviews were audiotaped, transcribed and subjected to thematic analysis employing a process of constant comparison in which data collection and analysis were cumulative and concurrent. The themes of perfect skin, societal ideals and media influence emerged from this iterative process. Respondents identified a societal ideal of flawless skin, largely mediated by media portrayals of perfection. Failure to meet this ideal precipitated psychological morbidity in female, but not male, respondents. An appreciation of the pervasive pressures of society and media upon females with skin disease may inform management strategies, particularly psychological management strategies, in patients with skin disease.
Culturally and linguistically diverse peoples' knowledge of accessibility and utilisation of health services: exploring the need for improvement in health service delivery
Authors: Henderson Saras , Kendall Elizabeth
Published: June 2011

With 28% of Australia’s population having a culturally and linguistically diverse (CALD) background, the health system faces an increasing challenge to provide accessible and culturally competent health care. The view that all CALD communities are homogenous and solutions can be developed for the entire nation is detrimental. Despite available health services, CALD communities are reluctant to use them due to cultural differences, perceived racism and misunderstandings leading to the existing health disparities. Therefore, gathering data from four prominent CALD communities, such as the Sudanese, Afghani, Pacific Islander and Burmese communities in Logan, Queensland, about how they perceive and use health services can provide insightful information towards development of a service model that will better suit these CALD communities. The objective of the study was to examine the extent to which four prominent CALD communities (Sudanese, Afghani, Pacific Islander and Burmese) access and use health services in Logan, Queensland. Six focus group interviews using interpreters were conducted in English with Sudanese, Afghani, Pacific Islander and Burmese people. The results indicated that even long-standing CALD communities, such as the Pacific Islander people, were unfamiliar with health services and experienced difficulties accessing appropriate health care. Most wanted doctors to use traditional healing methods alongside orthodox medicine, but did not feel respected for their beliefs. Language difficulties impeded communication with health professionals who were hindered by ineffective use of interpreters. In conclusion, a clear role for bilingual community-based navigators was identified by CALD participants to address concerns about the health system, and to improve accessibility and health service usage.
Involvement of KDM1C histone demethylase–OTLD1 otubain-like histone deubiquitinase complexes in plant gene repression
Authors: Krichevsky Alexander , Zaltsman Adi , Lacroix Benoît , Citovsky Vitaly
Published: June 2011

Covalent modifications of histones, such as acetylation, methylation and ubiquitination, are central for regulation of gene expression. Heterochromatic gene silencing, for example, is associated with hypoacetylation, methylation and demethylation, and deubiquitination of specific amino acid residues in histone molecules. Many of these changes can be effected by histone-modifying repressor complexes that include histone lysine demethylases, such as KDM1 in animals and KDM1C in plants. However, whereas KDM1-containing repressor complexes have been implicated in histone demethylation, methylation and deacetylation, whether or not they can also mediate histone deubiquitination remains unknown. We identify an
Arabidopsis
otubain-like deubiquitinase OTLD1 which directly interacts with the
Arabidopsis
KDM1C
in planta
, and use one target gene to exemplify that both OTLD1 and KDM1C are involved in transcriptional gene repression via histone deubiquitination and demethylation. We also show that OTLD1 binds plant chromatin and has enzymatic histone deubiquitinase activity, specific for the H2B histone. Thus, we suggest that, during gene repression, lysine demethylases can directly interact and function in a protein complex with histone deubiquitinases.
A dynamical model of ommatidial crystal formation
Authors: Lubensky David K. , Pennington Matthew W. , Shraiman Boris I. , Baker Nicholas E.
Published: June 2011

The crystalline photoreceptor lattice in the
Drosophila
eye is a paradigm for pattern formation during development. During eye development, activation of proneural genes at a moving front adds new columns to a regular lattice of R8 photoreceptors. We present a mathematical model of the governing activator–inhibitor system, which indicates that the dynamics of positive induction play a central role in the selection of certain cells as R8s. The “switch and template” patterning mechanism we observe is mathematically very different from the well-known Turing instability. Unlike a standard lateral inhibition model, our picture implies that R8s are defined before the appearance of the complete group of proneural cells. The model reproduces the full time course of proneural gene expression and accounts for specific features of the refinement of proneural groups that had resisted explanation. It moreover predicts that perturbing the normal template can lead to eyes containing stripes of R8 cells. We observed these stripes experimentally after manipulation of the
Notch
and
scabrous
genes. Our results suggest an alternative to the generally assumed mode of operation for lateral inhibition during development; more generally, they hint at a broader role for bistable switches in the initial establishment of patterns as well as in their maintenance.