bluuebunny/crossref_metadata_2025 huggingface dataset:
Adsorption/desorption of H2 and CO on Zn-modified Pd(111)
Authors: Tamtögl Anton , Kratzer Markus , Killman Jörg , Winkler Adolf
Published: December 2008

The adsorption and thermal desorption of H2 and CO on clean and Zn covered Pd(111) surfaces were studied using temperature programed desorption (TPD), low energy electron diffraction, and Auger electron spectroscopy. The obtained H2 and CO-TPD results reveal that thick Zn layers (≈10 ML) prepared at low temperature (150 K) block the adsorption of H2 and CO. However, the ZnPd surface alloy which is formed at temperatures above 300 K shows a different behavior. The amount of hydrogen adsorbed on surface sites is reduced by about 1/2 on the ZnPd surface alloy whereupon the diffusion of hydrogen into the subsurface region is not influenced. The initial sticking coefficient decreases from 0.5 on the clean surface to 0.14 on the ZnPd alloy. The TPD spectra for CO on the ZnPd surface alloy show that the heat of adsorption is shifted to much lower values than on clean Pd, yielding a desorption energy of 71±2 kJ mol−1 at low CO coverages. The saturation coverage equals 0.5 ML which means that each Pd atom of the ZnPd surface alloy is occupied by one CO admolecule. Interestingly, however, the initial sticking coefficient for CO on the ZnPd surface alloy is still unity, as on the clean Pd surface.
Influence of relative thickness on multiferroic properties of bilayered Pb(Zr0.52Ti0.48)O3–CoFe2O4 thin films
Authors: He Hong-cai , Ma Jing , Lin Yuanhua , Nan C. W.
Published: December 2008

Multiferroic bilayered thin films consisting of Pb(Zr0.52Ti0.48)O3 (PZT) and CoFe2O4 (CFO) layers of different relative thicknesses were prepared on a general Pt/Ti/SiO2/Si substrate via a simple solution processing. The influence of the thickness fraction on their properties including ferroelectric, ferromagnetic, and magnetoelectric properties in the PZT-CFO bilayered thin films was investigated. Our results showed that the thickness fractions (or relative thicknesses) of the layers have a significant effect not only on the magnetic and electric properties of the bilayered films but also on their magnetoelectric response. The bilayered thin films with the intermediate thickness fraction of around 0.6 exhibited a maximum magnetoelectric effect.
Misfit strain–misfit strain diagram of epitaxial BaTiO3 thin films: Thermodynamic calculations and phase-field simulations
Authors: Sheng G. , Zhang J. X. , Li Y. L. , Choudhury S. , Jia Q. X. , Liu Z. K. , Chen L. Q.
Published: December 2008

The effect of anisotropic strains on the phase transitions and domains structures of BaTiO3 thin films was studied using both thermodynamic calculations and phase-field simulations. The misfit strain–misfit strain domain stability diagrams were predicted. The similarity and significant differences between the diagrams from thermodynamic calculations assuming single domains and from phase-field simulations were analyzed. Typical domain structures as a result of anisotropic misfit strains are presented.
Measurement and evaluation of the interfacial thermal resistance between a metal and a dielectric
Authors: Chien Heng-Chieh , Yao Da-Jeng , Hsu Cheng-Ting
Published: December 2008

We used a sandwiched film structure of dielectric, metal, and dielectric to measure and also to estimate theoretically the metal-dielectric interfacial thermal resistance. In this structure, a metal layer with a thickness of about 10 nm, including chromium, titanium, aluminum, nickel, and platinum, is sandwiched between two SiO2 layers with a thickness of 100 nm prepared by plasma enhanced chemical vapor deposition. The estimates, 10−10–10−9 m2 K W−1, calculated with a continuum two-fluid model are significantly smaller than the measured values, ∼10−8 m2 K W−1. The continuum two-fluid model, according to the phenomena of electron-phonon nonequilibrium near the interface in a metal, cannot explain completely the cause of this metal-dielectric interfacial thermal resistance. From photographs of the transmission electron microscopy cross section, we argue that defects at an interface likely play an important role in the magnitude of the interfacial thermal resistance.
Applications of the Miller equilibrium to extend tokamak computational models
Authors: Stacey W. M.
Published: December 2008

An analytical model for the equilibrium flux surface geometry, widely known as the Miller equilibrium model, has been exploited to improve a variety of simplified tokamak computation models that incorporate an approximate flux surface geometry. Also discussed are improved models for an effective unelongated toroidal plasma representation of elongated flux surfaces; mapping temperature (and density) gradients measured at one poloidal location to other poloidal locations and to an average gradient over the flux surface; interpreting experimental heat diffusivities from local temperature gradients and average conductive heat fluxes; calculating the poloidal distribution of radial conductive heat fluxes; and evaluating the gyroviscous angular momentum transport rate.
Influence of alloy components on electromagnetic characteristics of core/shell-type Fe–Ni nanoparticles
Authors: Lu Bo , Huang Hao , Dong Xing Long , Zhang Xue Feng , Lei Jun Peng , Sun Jian Peng , Dong Chuang
Published: December 2008

Fe–Ni alloy nanoparticles with various alloy components were fabricated by a direct current arc-discharge method. By dispersing the nanoparticles homogeneously into a paraffin matrix, the complex permittivity (εr=εr′+iεr″) and permeability (μr=μr′+iμr″) of the nanoparticles have been investigated in the frequency range of 2–18 GHz and the effects of alloy components on the electromagnetic parameters were discussed. It is found that the permittivities of the nanoparticles are lower than those of the microscale counterparts and almost independent of frequency. The magnetic loss is attributed to natural resonance and the resonance peak shifts to high frequency range with the increase in Fe content. Better microwave absorption performances can be obtained by adjusting the composition and tailoring the core/shell structures to balance the electromagnetic parameters. The calculated results indicate that the Fe–Ni nanoparticles with 49 wt % Ni exhibit excellent electromagnetic wave (EMW) absorption properties (reflection loss <−20 dB) over the range of 7.6–16.0 GHz in the thickness of 1.02–1.70 mm. The mechanism of effective EMW introduction and attenuation is discussed on the basis of the experimental results.
Chiral states of electromagnetic fields originated from ferrite-based microwave vortices
Authors: Sigalov M. , Kamenetskii E. O. , Shavit R.
Published: December 2008

Electromagnetic vortices in a microwave cavity with an inserted piece of a magnetized ferrite appear due to the time-reversal symmetry breaking effect. We reveal numerically that the Poynting-vector vortices are possible in open resonant microwave structures with ferrite inclusions. We demonstrate a pair of resonances which have opposite vortex rotations at the same direction of time given by the direction of the magnetization precession. There are two coalescent resonances with different chirality. We show that the structures of the radiating near and far fields are intimately related to the ferrite-induced topological singularities. The observed far-field polarization structures represent a doublet of chiral vortices in space originated from a doublet of resonant chiral states in a patch resonator with an enclosed ferrite disk.
Short range ordering and magnetostriction in Fe–Ga and other Fe alloy single crystals
Authors: Guruswamy Sivaraman , Jayaraman Tanjore V. , Corson Robert P. , Garside Gavin , Thuanboon Swieng
Published: December 2008

The magnetostrictive behaviors of Fe–Ga, Fe–Mo, Fe–W, and other Fe alloys have been observed to be sensitive to their thermal history. In this work, the changes in the structure with thermal history and how they correlate with the observed magnetostriction values in Fe–Ga, Fe–W, and Fe–Mo single crystals are examined. Single crystals were grown using the vertical Bridgman crystal growth technique. The magnetostriction constant (3/2)λ100 measured in (i) as-grown and air-cooled (DG) and (ii) annealed and water quenched single crystal samples of Fe–Ga and Fe–W alloys clearly indicate that annealing in the α-phase region followed by rapid quenching improves the magnetostriction values. High-resolution x-ray diffraction (XRD) studies on [100]-oriented Fe–Ga as well as other Fe alloy single crystals show (i) a diffuse scattering peak indicative of short range ordering, the extent of which depends on composition and thermal history, and (ii) (200) peak splitting and broadening indicative of the presence of long range ordered coherent second phases and associated coherency strains. A detailed examination of the XRD patterns suggests that the changes in magnetostriction with composition and thermal history are related to the local strain modulations associated with the solutes, short range order, long range ordered coherent second phases, incoherent precipitates, and other structural defects.
Photothermal excitation and laser Doppler velocimetry of higher cantilever vibration modes for dynamic atomic force microscopy in liquid
Authors: Nishida Shuhei , Kobayashi Dai , Sakurada Takeo , Nakazawa Tomonori , Hoshi Yasuo , Kawakatsu Hideki
Published: December 2008

The authors present an optically based method combining photothermal excitation and laser Doppler velocimetry of higher cantilever vibration modes for dynamic atomic force microscopy in liquid. The frequency spectrum of a silicon cantilever measured in water over frequencies ranging up to 10 MHz shows that the method allows us to excite and detect higher modes, from fundamental to fifth flexural, without enhancing spurious resonances. By reducing the tip oscillation amplitude using higher modes, the average tip-sample force gradient due to chemical bonds is effectively increased to achieve high-spatial-resolution imaging in liquid. The method’s performance is demonstrated by atomic resolution imaging of a mica surface in water obtained using the second flexural mode with a small tip amplitude of 99 pm; individual atoms on the surface with small height differences of up to 60 pm are clearly resolved.
Charge loss behavior of a metal-alumina-nitride-oxide-silicon-type flash memory cell with different levels of charge injection
Authors: Chang Man , Jo Minseok , Kim Seonghyun , Ju Yongkyu , Jung Seungjae , Lee Joonmyoung , Yoon Jaesik , Hwang Hyunsang , Lee Choongman
Published: December 2008

We found that the charge loss behavior of metal-alumina-nitride-oxide-silicon-type flash memory was highly dependent on the amount of injected charge (Qinj). Beyond the critical level of Qinj, the direction of the dominant charge loss changed from pointing toward SiO2 to pointing toward Al2O3. The highly injected charges could cause the band bending of Al2O3, which reduced the tunneling distance across Al2O3 with the low conduction band offset. These results were verified by experimental results and theoretical device modeling through a comparison of the charge loss rate and the tunneling rate between a SiO2∕Si3N4∕SiO2 stack and a SiO2∕Si3N4∕Al2O3 stack.
Efficient readout of micromechanical resonator arrays in ambient conditions
Authors: Venstra W. J. , van der Zant H. S. J.
Published: December 2008

We present a method for efficient spectral readout of mechanical resonator arrays in dissipative environments. Magnetomotive drive and detection are used to drive double clamped resonators in the nonlinear regime. Resonators with almost identical resonance frequencies can be tracked individually by sweeping the drive power. Measurements are performed at room temperature and atmospheric pressure. These conditions enable application in high throughput resonant sensor arrays.
Experimental evidence of coupling between local turbulent transport and large scale fluctuations in the ISTTOK edge plasma
Authors: Silva C. , Hidalgo C. , Figueiredo H. , Duarte P. , Fernandes H. , Nedzelskiy I. , Pedrosa M. A.
Published: December 2008

The interplay between large scale fluctuations and the local turbulent transport has been investigated in the tokamak ISTTOK [C. A. F. Varandas et al., Fusion Technol. 29, 105 (1996)] plasma boundary region. It has been found that the floating potential fluctuations, dominated by low frequency oscillations, exhibit a significant toroidal correlation at large distances that can be attributed to the geodesic acoustic mode. The level of long-distance correlations is strongly bursty, showing a significant degree of coupling with the local electrostatic turbulent transport. Experimental findings show the key role of multiscale physics in the regulation of transport in the edge region of fusion plasmas.
Observation of collisionless heating of low energy electrons in low pressure inductively coupled argon plasmas
Authors: Lee Min-Hyong , Lee Hyo-Chang , Chung Chin-Wook
Published: December 2008

Collisionless heating of low energy electrons was observed in low pressure argon rf-biased inductively coupled plasmas (ICPs) by measurement of the electron energy distribution function (EEDF). When only capacitive power (bias) was supplied, the EEDF in the discharge was a bi-Maxwellian distribution with two electron groups. It was found that the low energy electrons were heated up significantly even with a little inductive power (<20 W) even when the discharge was in E mode. Due to the low gas pressure and low temperature of low energy electrons (close to the energy of the Ramsauer minimum), the collisional heating of low energy electrons appears to be negligible. Therefore, this effective heating of the low energy electrons showed a direct experimental evidence of the collisionless heating by inductive field. The significant heating of low energy electrons in E mode indicates that collisionless heating in the skin layer is an important electron heating mechanism of low pressure ICP even when the discharge is in E mode.
Visual observation and quantitative measurement of the microwave absorbing effect at X band
Authors: Zhao L. , Chen X. , Ong C. K.
Published: December 2008

We have set up a two-dimensional spatial field mapping system to measure graphically the quasi-free-space electromagnetic wave in a parallel plate waveguide. Our apparatus illustrates a potential application in characterizing the microwave absorbing materials. From the measured mappings of the microwave field, the visualization of spatial physical process and quantitative characterization of reflectivity coefficients can be achieved. This simple apparatus has a remarkable advantage over with conventional testing methods which usually involve huge, expensive anechoic chambers and demand samples of large size.
Microbeam-integrated multiphoton imaging system
Authors: Bigelow Alan W. , Geard Charles R. , Randers-Pehrson Gerhard , Brenner David J.
Published: December 2008

Multiphoton microscopy has been added to the array of imaging techniques at the endstation for the Microbeam II cell irradiator at Columbia University’s Radiological Research Accelerator Facility (RARAF). This three-dimensional (3D), laser-scanning microscope functions through multiphoton excitation, providing an enhanced imaging routine during radiation experiments with tissuelike samples, such as small living animals and organisms. Studies at RARAF focus on radiation effects; hence, this multiphoton microscope was designed to observe postirradiation cellular dynamics. This multiphoton microscope was custom designed into an existing Nikon Eclipse E600-FN research fluorescence microscope on the irradiation platform. Design details and biology applications using this enhanced 3D-imaging technique at RARAF are reviewed.
A time-resolved single-pass technique for measuring optical absorption coefficients of window materials under 100 GPa shock pressures
Authors: Li Jun , Zhou Xianming , Li Jiabo
Published: December 2008

An experimental method was developed to perform time-resolved, single-pass optical absorption measurements and to determine absorption coefficients of window materials under strong shock compression up to ∼200 GPa. Experimental details are described of (i) a configuration to generate an in situ dynamic, bright, optical source and (ii) a sample assembly with a lithium fluoride plate to essentially eliminate heat transfer from the hot radiator into the specimen and to maintain a constant optical source within the duration of the experiment. Examples of measurements of optical absorption coefficients of several initially transparent single crystal materials at high shock pressures are presented.
A scanning Hall probe microscope for high resolution magnetic imaging down to 300 mK
Authors: Khotkevych V. V. , Milošević M. V. , Bending S. J.
Published: December 2008

We present the design, construction, and performance of a low-temperature scanning Hall probe microscope with submicron lateral resolution and a large scanning range. The detachable microscope head is mounted on the cold flange of a commercial H3e-refrigerator (Oxford Instruments, Heliox VT-50) and operates between room temperature and 300 mK. It is fitted with a three-axis slip-stick nanopositioner that enables precise in situ adjustment of the probe location within a 6×6×7 mm3 space. The local magnetic induction at the sample surface is mapped with an easily changeable microfabricated Hall probe [typically GsAs/AlGaAs or AlGaAs/InGaAs/GaAs Hall sensors with integrated scanning tunnel microscopy (STM) tunneling tips] and can achieve minimum detectable fields ⩾10 mG/Hz1/2. The Hall probe is brought into very close proximity to the sample surface by sensing and controlling tunnel currents at the integrated STM tip. The instrument is capable of simultaneous tunneling and Hall signal acquisition in surface-tracking mode. We illustrate the potential of the system with images of superconducting vortices at the surface of a Nb thin film down to 372 mK, and also of labyrinth magnetic-domain patterns of an yttrium iron garnet film captured at room temperature.
Large fires, fire effects and the fire-regime concept
Authors: Gill A. Malcolm , Allan Grant
Published: December 2008

‘Large’ fires may be declared so because of their absolute or relative area. Huge fires – with areas of more than 106 ha (104 km2) have occurred across a wide spectrum of Australian environments and are known on other continents. Such large fires are rare whereas fires with much smaller areas are common. Large fires are initiated by single or multiple ignitions and become large because of some combination of: rapid rates of spread; long ‘life’; merging, and failure of initial suppression operations. Fires as ecological ‘events’ occur within a ‘regime’ – an historical series. Both events and regimes have effects that may be discerned in terms of water, land, air or organisms. What have been regarded as the components of ‘regimes’ have differed between observers, the main issue being whether or not spatial variables need to be included; ‘area’ involvement is briefly addressed. The current trend toward fire-regime control through fuel treatment, including management (prescribed) burning, and fire suppression may be expected to continue. These trends, among others, can be expected to change fire regimes. What is regarded as ‘large’ among fires may change as the planet becomes increasingly human-dominated.
Landscape heterogeneity following large fires: insights from Yellowstone National Park, USA
Authors: Schoennagel Tania , Smithwick Erica A. H. , Turner Monica G.
Published: December 2008

We characterised the remarkable heterogeneity following the large, severe fires of 1988 in Yellowstone National Park (YNP), in the northern Rocky Mountains, Wyoming, USA, by focussing on spatial variation in post-fire structure, composition and ecosystem function at broad, meso, and fine scales. Ecological heterogeneity at multiple scales may enhance resilience to large, severe disturbances by providing structural, biological and functional redundancy. Post-fire heterogeneity in stand age, coarse wood abundance, microbial and understorey communities reflected interactions between existing pre-fire patterns and fire severity at different scales, suggesting that environmental context plays an important role in successional responses to large fires. In response to these post-fire patterns, heterogeneity in carbon (C) and nitrogen (N) storage, N mineralisation, decomposition, and productivity was also evident at multiple scales and may confer resiliency to large fires. For example, at broad scales, C storage in YNP appears resistant to changes in age-class structure associated with large stand-replacing fires. In summary, the YNP landscape is recovering rapidly from the 1988 fires through natural mechanisms, owing to the abundance and spatial heterogeneity of post-fire residuals, but other systems with fewer biotic legacies may be less resilient to such large, severe fires.
Ecological effects of large fires on US landscapes: benefit or catastrophe?
Authors: Keane Robert E. , Agee James K. , Fulé Peter , Keeley Jon E. , Key Carl , Kitchen Stanley G. , Miller Richard , Schulte Lisa A.
Published: December 2008

The perception is that today’s large fires are an ecological catastrophe because they burn vast areas with high intensities and severities. However, little is known of the ecological impacts of large fires on both historical and contemporary landscapes. The present paper presents a review of the current knowledge of the effects of large fires in the United States by important ecosystems written by regional experts. The ecosystems are (1) ponderosa pine–Douglas-fir, (2) sagebrush–grasslands, (3) piñon–juniper, (4) chaparral, (5) mixed-conifer, and (6) spruce–fir. This review found that large fires were common on most historical western US landscapes and they will continue to be common today with exceptions. Sagebrush ecosystems are currently experiencing larger, more severe, and more frequent large fires compared to historical conditions due to exotic cheatgrass invasions. Historical large fires in south-west ponderosa pine forest created a mixed severity mosaic dominated by non-lethal surface fires while today’s large fires are mostly high severity crown fires. While large fires play an important role in landscape ecology for most regions, their importance is much less in the dry piñon–juniper forests and sagebrush–grasslands. Fire management must address the role of large fires in maintaining the health of many US fire-dominated ecosystems.
Large fires as agents of ecological diversity in the North American boreal forest
Authors: Burton Philip J. , Parisien Marc-André , Hicke Jeffrey A. , Hall Ronald J. , Freeburn Jason T.
Published: December 2008

The present study undertook a hierarchical analysis of the variability within and among some individual fire events in the boreal ecozones of Canada and Alaska. When stratified by ecozone, differences in the spatial and temporal distribution of wildfires were observed in the Canadian Large Fire Data Base that reflect climatic, terrain and land-use differences across the country. Remote-sensing data collected before and after boreal forest fires permitted a rigorous analysis of the variability in burn severity within individual fire events, and the identification of certain fire-prone and more fire-resistant land-cover types. The occurrence of fire skips or islands was related to the distribution of those cover types, resulting in proportionally more unburned area within the perimeter of a burn for larger fires. Differences in burn severity led to differences in post-burn vegetation response of tree, shrub and moss layers that can persist for decades or even centuries. As a result, there can be considerable variability in the survival, density and distribution of residual biota and organic materials. This variability creates a range of post-fire vegetation patterns and contributes much to the habitat diversity of boreal landscapes.
Big fires and their ecological impacts in Australian savannas: size and frequency matters
Authors: Yates Cameron P. , Edwards Andrew C. , Russell-Smith Jeremy
Published: December 2008

Savannas are the most fire-prone of the earth’s major biomes. The availability of various broad-scale satellite-derived fire mapping and regional datasets provides a framework with which to examine the seasonality, extent and implications of large fires with particular reference to biodiversity values in the tropical savannas of northern Australia. We document the significance of savanna fires in the fire-prone ‘Top End’ region of the Northern Territory, Australia, using 9 years (1997–2005) of National Oceanic and Atmospheric Administration (NOAA)-Advanced Very High Resolution Radiometer (AVHRR)-, Landsat Thematic Mapper (TM)- and Enhanced Thematic Mapper (ETM+)-derived fire mapping. Fire (patch) sizes from both AVHRR- and Landsat-scale mapping increased through the calendar year associated with progressive curing of grass and litter fuels. Fire frequency data at both satellite sensor scales indicate that regional fire regimes in higher rainfall regions are dominated by large (>1000 km2) fires occurring typically at short (~2–3 years) fire return intervals. In discussion, we consider the ecological implications of these patch size distributions on regional fire-sensitive biota. Collectively, assembled data illustrate that many northern Australian savanna flora, fauna and habitats embedded within the savanna matrix are vulnerable to extensive and frequent fires, especially longer-lived obligate seeder plant taxa and relatively immobile vertebrate fauna with small home ranges.
Are wildfires a disaster in the Mediterranean basin? - A review
Authors: Pausas Juli G. , Llovet Joan , Rodrigo Anselm , Vallejo Ramon
Published: December 2008

Evolutionary and paleoecological studies suggest that fires are natural in the Mediterranean basin. However, the important increase in the number of fires and area burned during the 20th century has created the perception that fires are disasters. In the present paper, we review to what extent fires are generating ecological disasters in the Mediterranean basin, in view of current fire regimes and the long-term human pressure on the landscapes. Specifically, we review studies on post-fire plant regeneration and soil losses. The review suggests that although many Mediterranean ecosystems are highly resilient to fire (shrublands and oak forest), some are fire-sensitive (e.g. pine woodlands). Observed erosion rates are, in some cases, relatively high, especially in high fire severity conditions. The sensitive ecosystems (in the sense of showing strong post-fire vegetation changes and soil losses) are mostly of human origin (e.g. extensive pine plantations in old fields). Thus, although many Mediterranean basin plants have traits to cope with fire, a large number of the ecosystems currently found in this region are strongly altered, and may suffer disasters. Post-fire disasters are not the rule, but they may be important under conditions of previous human disturbances.
Large fires and their ecological consequences: introduction to the special issue
Authors: Williams Richard J. , Bradstock Ross A.
Published: December 2008

In the last decade, extensive fires have occurred on most continents, affecting a wide range of ecosystems. We convened a Symposium at the 3rd International Fire Ecology and Management Congress in 2006 to address the issue of large fires and their ecological consequences in landscapes. The 10 papers presented here variously discuss the place of large fires in the context of historical fire regimes, the heterogeneity of fire regime components that are associated with large fires, and the ecological consequences of large fires. The discussions cover a range of biomes, from tropical to temperate, across the world. Three consistent themes emerged: firstly, large fires are usually a part of the Historical Range of Variability; secondly, large fires are inherently heterogeneous, leaving footprints of spatial and temporal diversity that may influence landscapes for decades; and thirdly, large fires have been perceived as socially and ecologically ‘disastrous’, due to obvious and significant deleterious effects on life and property, and the scale of immediate environmental impact. However, the papers presented here indicate that the long-term ecological impacts of individual large fires are not necessarily disastrous. Crucial impacts of large fires on ecosystems may depend largely on their rate of recurrence as well as landscape-scale variation in severity. The incidence and characteristics of large fires may change in the future, as a consequence of global climate change, and other social drivers of landscape change.
Chinese character recognition in mirror reading: Evidence from event‐related potential
Authors: Zhang Ye , Qiu Jiang , Huang He , Zhang Qinglin , Bao Baier
Published: December 2008

As is well known, mirror reading in language requires recognition of words and letters in mirror‐reversed pattern compared with normal reading, and the cognitive mechanism underlying the mirror reading may involve two critical processes: visuospatial transformation and linguistic regulation. Chinese characters, different from English, are characterized by some unique features in orthography and spelling. Using ERP techniques, the present study investigated neural correlates underlying the mirror reading of Chinese characters, and whether the cognitive processes underlying the recognition of mirrored Chinese characters is different from those of alphabetic words. Twelve native Chinese speakers participated in the experiment, during which they were instructed to make an animal/nonanimal distinction. The stimuli varied with the word category (animal vs nonanimal) and presentation format (normal vs mirror‐reversed). The data analyses focused on three aspects: the reaction times (RT) for Chinese words of normal and mirror‐reversed formats, peak latencies, and peak amplitudes of ERP components elicited by mirror‐reversed and normal Chinese words. The results from implicit reading provide evidence for a mirror‐reversed effect. The behavioural data showed that mirror‐reversed words were more difficult to identify than normal words, with RTs delayed for mirror‐reversed words over normal words. Moreover, a clear N2 component, with maximal activity occurring at 200–250ms interval (N2), was more negative for mirror‐reversed words than for normal words at posterior regions. However, there were no latency differences between normal and mirror‐reversed words. The occipital N2 might be closely related to abstract word form representation. Larger N2 amplitude in response to mirror‐reversed Chinese words is interpreted as reflecting visuospatial transformation in order to compensate for impaired word form analysis. The result of no N2 latency delay indicated that word form analysis and visuospatial transformation might be processed in parallel.
A cross‐curricular approach to ‘learning to learn’ languages: government policy and school practice
Authors: Harris Vee
Published: December 2008

This article connects two fields of research: ‘learning to learn’ and school‐based teacher development. The context is a cross‐curricular project between English and modern languages teachers. Carried out in two London schools, the study aimed to encourage students to transfer common language learning strategies across the two subjects. Findings from interviews with teachers and students highlight the gap between the government's ‘learning to learn’ agenda and the realities of implementing it. A distinction is drawn between providing school‐based opportunities for teachers to share generic ‘good practice’ in relation to initiatives such as Assessment for Learning and those where the actual content of lessons crosses subject boundaries. Recent government guidelines appear to mask inherent tensions in the aims and pedagogical approaches of the two languages – tensions exacerbated by the current preoccupation with performance measures. It is suggested that the differences are unlikely to be resolved without a supportive school culture that provides adequate release time for teachers to engage in extensive cross‐curricular dialogue.
Thoughts on teaching thinking: perceptions of practitioners with a shared culture of thinking skills education
Authors: Jones Hanneke
Published: December 2008

This article aims to outline the reported experiences of practitioners in a local authority in England where, since the mid‐1990s, a high proportion of teachers have undertaken professional development in the field of teaching thinking skills. The article is based on the main findings from a questionnaire survey which was carried out among first, middle and high school teachers in this area. It was intended to explore their views on the use, benefits and challenges of teaching ‘Thinking for Learning’, a term which encompasses both the use of a range of thinking skills strategies and the Community of Enquiry/Philosophy for Children approaches.

The vast majority of respondents reported a range of positive effects on their pupils, including pupil motivation and cognitive, social and affective benefits. On the other hand, reported challenges mainly referred to a perceived lack of time and to some seemingly inherent difficulties in the teaching of thinking.

Conclusions from this study have the potential to inform professional development practice and policy far beyond this local authority's regional boundaries, and aim to contribute to the body of knowledge about forms of education that are based on dialogue and enquiry.
Economies of space and the school geography curriculum
Authors: Morgan John
Published: December 2008

This article is about the images of economic space that are found in school curricula. It suggests the importance for educators of evaluating these representations in terms of the messages they contain about how social processes operate. The article uses school geography texts in Britain since the 1970s to illustrate the different ways in which economic space has been represented to students, before exploring some alternative resources that could be used to provide a wider range of representations of economic space. It highlights the continued importance of understanding the politics of school knowledge.
Assessing Text Processing: A Comparison of Four Methods
Authors: Scott D. Beth
Published: December 2008

Tests commonly used to determine progress in reading skill and proficiency typically assess reading products (e.g., identifying characters or factual information, sequencing events) rather than the reading processes used to generate responses (e.g., hypothesizing, evaluating, monitoring, questioning). Yet, effective processing often determines how successfully a reader responds on testing measures. Identifying measures that can assist educators to better understand how a student processes text is vital. The purpose of this research was to compare the data generated from 4 assessment methods used to evaluate how readers process text: think-aloud, interview, error detection, and questionnaire. In this descriptive study, 40 fourth-grade students of average reading ability read the same text, and data were collected as each student responded to 1 of the 4 assessment measures. Results indicated that students assessed with think-aloud and interview measures generated a greater number and broader range of text processing responses. Think-aloud protocols reflected a close interaction with text while interview responses included more evidence of metacognitive processing. Issues frequently identified as problematic in error detection research (e.g., difficulty finding errors, purpose for reading) are supported in this study. The questionnaires provide less specific data about individual text processing since students were limited by the answer choices for each question. Results from this study suggest that by using think-aloud and interview assessments, educators can obtain a more complete understanding of a reader's text processing skill than by using error-detection and questionnaire methods.
From Storytelling to Writing: Transforming Literacy Practices among Sudanese Refugees
Authors: Perry Kristen H.
Published: December 2008

This paper presents an analysis of the ways in which a community of orphaned Southern Sudanese refugee youth—the “Lost Boys of Sudan”—transformed traditional practices of storytelling as they adjusted to life in the U.S. The result of their experiences as orphaned refugees, this transformation discloses larger issues related to literacy, identity and community for these youth. Theoretical perspectives regarding literacy and storytelling as social practices, reflecting participants' social, cultural, and political contexts, framed this research. Focal participants were 3 orphaned young men, all refugees from Southern Sudan. Ethnographic methods including participant observation, semi-structured interviews, and artifact collection contributed to data collection. Data analysis consisted of coding field notes and interview transcripts for emerging themes and conducting discourse analyses on interview transcripts. Results indicated that participants acted as storytellers and also talked explicitly about storytelling's cultural importance. Participants transformed the act of storytelling by altering the purposes, audiences, and media for storytelling that they had encountered or told before. Transformed storytelling revealed the importance of both becoming educated in the U.S. and also of maintaining a sense of Sudanese identity and community among these refugee youth. Their stories also reflected an important tension between orphan identity and maintaining a sense of Sudanese community, as well as a focus on educating non-Sudanese about refugees' experiences.
Animated triangles: An eye tracking investigation
Authors: Klein Annette M. , Zwickel Jan , Prinz Wolfgang , Frith Uta
Published: December 2008

We presented three types of animations on an eye tracking monitor to 31 adult participants. In line with previous work, verbal descriptions of these animations indicate that one type (theory of mind or ToM) evokes mental state attributions, while another type (random) does not, with an intermediate category (goal-directed) evoking a moderate amount of mental state attributions. We expected longer fixations with greater depth of processing, which we assume is required for mental state attributions. In line with this expectation we found that the ToM animations invited long fixations; the random animations invited short fixations, while the goal-directed animations invited an intermediate amount of fixations, with some clips inviting shorter and others longer fixations. These findings demonstrate that it is possible to capture systematic differences in behaviour while viewing animations not only by means of a verbal measure, but also in terms of a simple measure of eye movements.
Simulation of crosstalk between small GTPase RhoA and EGFR-ERK signaling pathway via MEKK1
Authors: Li Hu , Ung Choong Yong , Ma Xiao Hua , Li Bao Wen , Low Boon Chuan , Cao Zhi Wei , Chen Yu Zong
Published: December 2008

Motivation: Small GTPase RhoA regulates cell-cycle progression via several mechanisms. Apart from its actions via ROCK, RhoA has recently been found to activate a scaffold protein MEKK1 known to promote ERK activation. We examined whether RhoA can substantially affect ERK activity via this MEKK1-mediated crosstalk between RhoA and EGFR-ERK pathway. By extending the published EGFR-ERK simulation models represented by ordinary differential equations, we developed a simulation model that includes this crosstalk, which was validated with a number of experimental findings and published simulation results.

Results: Our simulation suggested that, via this crosstalk, RhoA elevation substantially prolonged duration of ERK activation at both normal and reduced Ras levels. Our model suggests ERK may be activated in the absence of Ras. When Ras is overexpressed, RhoA elevation significantly prolongs duration of ERK activation but reduces the amount of active ERK partly due to competitive binding between ERK and RhoA to MEKK1. Our results indicated possible roles of RhoA in affecting ERK activities via MEKK1-mediated crosstalk, which seems to be supported by indications from several experimental studies that may also implicate the collective regulation of cell fate and progression of cancer and other diseases.

Contact:  phacyz@nus.edu.sg

Supplementary information:  Supplementary data are available at Bioinformatics online.
Effects of Ferulic Acid and Transglutaminase on Hard Wheat Flour Dough and Bread
Authors: Koh Bong‐Kyung , Ng Perry K. W.
Published: December 2008

The effects of ferulic acid and transglutaminase (TG) on the properties of wheat flour dough and bread were investigated. Ferulic acid and TG were blended with hard wheat flour at levels of 250 and 2,000 ppm of flour weight, respectively. The addition of ferulic acid reduced the mixing time and mixing tolerance. The addition of TG did not obviously affect the mixing properties. Significant effects of ferulic acid plus TG on the rested dough texture were observed for overmixed dough. The maximum resistance (Rmax) of the dough was significantly reduced with the addition of ferulic acid but increased with the addition of TG. The addition of TG with ferulic acid restored the Rmax reduced by ferulic acid alone. The proportion of SDS‐soluble high molecular weight proteins in the dough increased with the addition of ferulic acid and decreased with TG, when assessed with size‐exclusion HPLC fractionation. Although the addition of TG improved the handling properties of the dough made sticky with added ferulic acid, it did not improve the quality of the bread with added ferulic acid as measured by loaf volume and firmness.
The coupling of winds, aerosols and chemistry in Titan's atmosphere
Authors: Lebonnois Sebastien , Rannou Pascal , Hourdin Frederic
Published: December 2008

The atmosphere of Titan is a complex system, where thermal structure, radiative transfer, dynamics, microphysics and photochemistry are strongly coupled together. The global climate model developed over the past 15 years at the Pierre-Simon Laplace Institute has been exploring these different couplings, and has demonstrated how they can help to interpret the observed atmospheric structure of Titan's lower atmosphere (mainly in the stratosphere and troposphere). This review discusses these interactions, and our current understanding of their role in the context of this model, but also of other available works. The recent Cassini results, and the importance of the production mechanisms for Titan's haze, have put forward the need to explore the mesosphere and the couplings between upper and lower atmosphere, as well as the current limits of available models.
Titan's exosphere and its interaction with Saturn's magnetosphere
Authors: Dandouras Iannis , Garnier Philippe , Mitchell Donald G , Roelof Edmond C , Brandt Pontus C , Krupp Norbert , Krimigis Stamatios M
Published: December 2008

Titan's nitrogen-rich atmosphere is directly bombarded by energetic ions, due to its lack of a significant intrinsic magnetic field. Singly charged energetic ions from Saturn's magnetosphere undergo charge-exchange collisions with neutral atoms in Titan's upper atmosphere, or exosphere, being transformed into energetic neutral atoms (ENAs). The ion and neutral camera, one of the three sensors that comprise the magnetosphere imaging instrument (MIMI) on the Cassini/Huygens mission to Saturn and Titan, images these ENAs like photons, and measures their fluxes and energies. These remote-sensing measurements, combined with the
in situ
measurements performed in the upper thermosphere and in the exosphere by the ion and neutral mass spectrometer instrument, provide a powerful diagnostic of Titan's exosphere and its interaction with the Kronian magnetosphere. These observations are analysed and some of the exospheric features they reveal are modelled.
Characteristics and variability of Titan's magnetic environment
Authors: Bertucci César L
Published: December 2008

The structure and variability of Saturn's magnetic field in the vicinity of Titan's orbit is studied. In the dawn magnetosphere, the magnetic field presents a significant radial component directed towards Saturn, suggesting that Titan is usually located below the planet's warped and dynamic magnetodisc. Also, a non-negligible component along the co-rotation direction suggests that Saturn's magnetic field lines close to the magnetodisc are being swept back from their respective magnetic meridians. In the noon sector, Titan seems to be closer to the magnetodisc central current sheet, as the field lines in this region seem to be more dipolar. The distance between the central current sheet and Titan depends mainly on the solar wind pressure. Also,
δ
|
B
|/|
B
|∼0.5 amplitude waveforms at periods close to Saturn's kilometric radiation period are present in the background magnetic field. This modulation in the field is ubiquitous in Saturn's magnetosphere and associated with the presence of a rotating asymmetry in the planet's magnetic field.
An outbreak of oropharyngeal tularaemia linked to natural spring water
Authors: Willke A. , Meric M. , Grunow R. , Sayan M. , Finke E. J. , Splettstößer W. , Seibold E. , Erdoğan S. , Ergonul O. , Yumuk Z. , Gedikoglu S.
Published: December 2008

A tularaemia outbreak was investigated involving 188 suspected cases in the Kocaeli region of Turkey between December 2004 and April 2005. A case–control study comprising 135 laboratory-confirmed cases and 55 controls was undertaken to identify risk factors for the development of the outbreak and to evaluate laboratory diagnostic methods. Tularaemia was confirmed by a microagglutination test (MAT) titre of ≥1 : 160 in 90 of the patients. In MAT-negative sera, 23/44 (52 %) were positive by ELISA withFrancisella tularensisLPS and 1/9 (11 %) by Western blotting with this antigen. A species-specific PCR was positive in 16/25 (64 %) throat swabs and 8/13 (62 %) lymph node aspirates. Multivariate analysis showed that drinking natural spring water was the leading risk factor for the development of tularaemia (P=0.0001, odds ratio 0.165, 95 % CI 0.790–0.346). The outbreak ceased after abandonment of the suspected natural water springs.
Interaction analyses of human monocytes co-cultured with different forms of Aspergillus fumigatus
Authors: Loeffler Juergen , Haddad Ziad , Bonin Michael , Romeike Nele , Mezger Markus , Schumacher Ulrike , Kapp Markus , Gebhardt Florian , Grigoleit Goetz-Ulrich , Stevanović Stefan , Einsele Hermann , Hebart Holger
Published: December 2008

Monocytes play a major role in the cellular defence against Aspergillus fumigatus in immunocompromised patients. To obtain a better understanding of the mechanisms involved in this interaction, phagocytosis and gene expression profiling of human monocytes was carried out after incubation with A. fumigatus resting, swollen and germinating conidia and hyphae (for 3, 6 and 9 h). The majority of monocytes phagocytosed up to three conidia during the first 3 h of incubation. Microarray analysis showed an increased expression level of immune-relevant genes, which was dependent on the germination state of the fungus and the incubation period. Among these genes, those encoding interleukin-8, macrophage inflammatory protein 3-α (CCL20) and monocyte chemotactic protein-1 (CCL2) were found to be potential key regulators involved in the A. fumigatus-induced immune response. In addition, A. fumigatus was found to be an inducer of the genes encoding urokinase type plasminogen activator (uPA), urokinase type plasminogen activator receptor (uPAR),plasminogen activator inhibitor (PAI), pentraxin-3 (PTX3) and intercellular adhesion molecule-1 (ICAM-1), which, in combination, may contribute to thrombosis and local lung tissue injury.