bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultraviolet and infrared observations of Saturn's auroral oval
Authors: Balcerak Ernie
Published: October 2011

New observations of Saturn's southern auroral oval made simultaneously in ultraviolet (UV) and infrared (IR) wavelengths show how complex and dynamic the auroral oval is. Melin et al. present high‐spatial‐resolution observations from the Cassini spacecraft's UV and IR instruments. The auroral oval varies over short time scales and has many small‐scale structures. The researchers observed three different arcs within the auroral oval, which they suggest are probably caused by precipitation of particles with different energies. In addition, the researchers found that the main auroral oval is morphologically similar in UV and IR, but in the auroral emissions equatorward and poleward of the main oval, there are noticeable differences in UV and IR, highlighting the need for observations at a range of wavelengths. (Geophysical Research Letters, doi:10.1029/2011GL048457, 2011)
Farmers' past choices enhance mitigation potential of reforestation
Authors: Balcerak Ernie
Published: October 2011

Land cover changes such as clearing forests to create farmland influence climate not only by changing the amount of carbon dioxide (CO2) absorbed by the vegetation but also by changing the albedo, the fraction of sunlight reflected back to space. These two effects often oppose each other. For instance, farmland may absorb less CO2 than forests, contributing to warming; but at the same time, farmland tends to reflect more light than forests, contributing to cooling. This cooling is strongest in northern latitudes because highly reflective snow is hidden under dark trees when covering agricultural fields.
Models fail to capture Arctic ice thinning, drift trends
Authors: Balcerak Ernie
Published: October 2011

Observations have shown that Arctic sea ice extent has declined over the past several decades and that this decline has accelerated in recent years. However, climate models used in the Intergovernmental Panel on Climate Change (IPCC) fourth assessment report underestimate the observed decrease in ice extent. Furthermore, Rampal et al. studied 13 IPCC models and found that the models underestimate Arctic sea ice thinning by about a factor of 4 on average. In addition to thinning, observations show that Arctic sea ice is drifting more rapidly, but the authors found that the climate models do not capture this drift acceleration. The authors note that in most of the models, sea ice drifts faster when it is thicker, contrary to observations, which show thinner ice drifting faster. Faster drift increases the rate at which ice flows out of the Arctic. The models' weak coupling between ice thickness and drift velocity partly explains the models' underestimation of ice area, thickness, and velocity trends.
Enhanced H2 sensitivity at room temperature of ZnO nanowires functionalized by Pd nanoparticles
Authors: Ren Shoutian , Fan Guanghua , Qu Shiliang , Wang Qiang
Published: October 2011

For sensitive detection of H2, ZnO nanowires networks decorated with photo-decomposed Pd nanoparticles were fabricated between femtosecond laser-writing interdigitated electrodes by chemical vapor deposition method. When H2 concentration is increased from 20 to 4000 ppm at room temperature, sensitivity of the sample is increased from 3.7% to 1017.9%. The high sensitivity can be explained by considering the reaction between the adsorbed O2- and the disassociated H atoms facilitated by Pd nanoparticles. This mechanism is further supported by the H2 response results under UV light illumination, which can reduce the amount of O2- on the ZnO surface, leading to depressed sensitivity. The sensor also shows high selectivity, long-term stability, and ultra-low power consumption of nanowatt level, due to the novel fabrication process.
Optical characterization of the quantum capacitance detector at 200 μm
Authors: Bueno J. , Llombart N. , Day P. K. , Echternach P. M.
Published: October 2011

We present the optical characterization at 200 μm wavelength of an antenna coupled quantum capacitance detector (QCD), a cryogenic detector based on a single Cooper pair box (SCB). The response of the device to a cryogenic blackbody source and the device noise have been measured giving an optical noise-equivalent power (NEP) at a readout frequency of 10 kHz of 2 × 10−17 W/Hz1/2 at an optical loading of 17 fW. For optical loadings of a few pW, the optical NEP was on the order of 10−16 W/Hz1/2, demonstrating that QCDs could already work as detectors for far-infrared and submillimeter wave radiation in a ground based telescope.
Lattice dynamics and substrate-dependent transport properties of (In, Yb)-doped CoSb3 skutterudite thin films
Authors: Sarath Kumar S. R. , Cha Dongkyu , Alshareef H. N.
Published: October 2011

Lattice dynamics, low-temperature electrical transport, and high-temperature thermoelectric properties of (In, Yb)-doped CoSb3 thin films on different substrates are reported. Pulsed laser deposition under optimized conditions yielded single-phase polycrystalline skutterudite films. Raman spectroscopy studies suggested that In and Yb dopants occupy the cage sites in the skutterudite lattice. Low-temperature electrical transport studies revealed the n-type semiconducting nature of the films with extrinsic and intrinsic conduction mechanisms, in sharp contrast to the degenerate nature reported for identical bulk samples. Calculations yielded a direct bandgap close to 50 meV with no evidence of an indirect gap. The carrier concentration of the films was identical to that reported for the bulk and increased with temperature beyond 250 K. The higher resistivity exhibited is attributed to the enhanced grain boundary scattering in films with a high concentration of grains. The maximum power factor of ∼0.68 W m−1 K−1 obtained at 660 K for the film on glass is found to be nearly four times smaller compared to that reported for the bulk. The observed difference in the power factors of the films on different substrates is explained on the basis of the diffusion of oxygen from the substrates and the formation of highly conducting CoSb2 phase upon the oxidation of CoSb3.
Dirac operators on the fuzzy AdS2 with the spins $\frac{1}{2}$12 and 1
Authors: Fakhri H. , Lotfizadeh M.
Published: October 2011

It is shown here how the pseudo chirality and Dirac operators with the spins \documentclass[12pt]{minimal}\begin{document}$\frac{1}{2}$\end{document}12 and 1 on the commutative and fuzzy AdS2 should be constructed. The finite-dimensional and nonunitary representations of SU(1, 1) carrying the spin degrees of freedom \documentclass[12pt]{minimal}\begin{document}$\frac{1}{2}$\end{document}12 and 1 are used for the Dirac fields on commutative and fuzzy AdS2. In the fuzzy case, an explicit description of pseudo generalization of the Ginsparg-Wilson algebra is used to construct projective modules. The projector couplings left angular momentum and spin on the fuzzy AdS2 are used to produce minimum total angular momenta. They are realized by the first two and three representations of the total angular momentum for the spins \documentclass[12pt]{minimal}\begin{document}$\frac{1}{2}$\end{document}12 and 1, respectively. The pseudo projectors, the pseudo chirality, and Dirac operators with the spins \documentclass[12pt]{minimal}\begin{document}$\frac{1}{2}$\end{document}12 and 1 on the fuzzy AdS2 tend to their corresponding operators in the commutative limit.
Study of plasmonic crystals using Fourier-plane images obtained with plasmon tomography far-field superlenses
Authors: Rodriguez R. , Regan C. J. , Ruiz-Columbié A. , Agutu W. , Bernussi A. A. , Grave de Peralta L.
Published: October 2011

We explore the use of surface plasmon polariton (SPP) tomography far-field superlenses for quantitative characterization of plasmonic crystals with sub-wavelength features. Essential information concerning the dependence of the effective refractive index on the hole diameter and the filling factor was obtained from the Fourier-plane images of the fabricated plasmonic crystals. We also provide a comprehensive discussion on the influence of hole diameters on the formation of directional stop-bands in plasmonic crystals.
Extremely uniform bound exciton states in nitrogen δ-doped GaAs studied by photoluminescence spectroscopy in external magnetic fields
Authors: Harada Yukihiro , Kubo Terutada , Inoue Tomoya , Kojima Osamu , Kita Takashi
Published: October 2011

We studied the spatial localization of excitons bound to nitrogen (N) pairs in N δ-doped GaAs to make clear origin of bound exciton lines. An extremely high uniformity of the emission wavelength was achieved for the exciton bound to the N pairs because of the uniform strain field in the N δ-doped layer fabricated in the (001) plane in the atomically controlled way. The magneto-photoluminescence spectra in the Faraday configuration showed a mixing of the bright- and dark-exciton components in the exciton fine structure and diamagnetic shift. The spatial distribution of the excitons localized at different N pairs was estimated using the diamagnetic shift coefficient and confirmed by the radiative lifetime of the bright-exciton component. According to the estimated spatial distribution of bound-exciton wave function, it was found that the exciton for the 1.444-eV line is localized stronger than that for the 1.493-eV line. The strong electron confinement for the 1.444-eV line results in the reduction of exciton-phonon interaction.
Side-gate effects on the direct current and radio frequency characteristics of AlGaN/GaN high-electron-mobility transistor on Si
Authors: Zhou Hong , Ing Ng Geok , Hong Liu Zhi , Arulkumaran Subramaniam
Published: October 2011

The influence of the side-gate bias on the direct current and radio frequency characteristics for a GaN high electron mobility transistor is studied. When the side-gate is biased at large negative bias (VSG = −100 V), the maximum drain current density (Idmax), maximum extrinsic transconductance (gmmax), cut-off frequency (fT), and maximum oscillation frequency (fmax) of the device are reduced and the threshold voltage (Vth) is positively shifted. The drain leakage current under pinch-off is decreased. In contrast, when VSG is positive, there are only small changes for the fT, fmax, Idmax, gmmax, and Vth. The drain leakage current under pinch-off condition is increased at VSG = +100 V. It is believed that the electrical field effect and buffer depletion caused by the additional side gate voltage contribute to those changes.
Wide-range control of ferromagnetic resonance by spin Hall effect
Authors: Demidov V. E. , Urazhdin S. , Edwards E. R. J. , Demokritov S. O.
Published: October 2011

We demonstrate experimentally that the characteristics of the ferromagnetic resonance in a microscopic magnetic system based on a Permalloy/Cu/Pt multilayer can be varied over a wide range by the spin Hall effect. Specifically, by applying a dc current through the Pt strip, we achieve a reduction of the effective damping constant in Permalloy by a factor of two below its standard value. We show that this reduction is not significantly affected by the Joule heating effects. We also find that, apart from influencing the damping, the spin Hall effect results in the amplification or suppression of the coherent magnetization dynamics.
Size-affected shear-band speed in bulk metallic glasses
Authors: Liu Z. Y. , Yang Y. , Liu C. T.
Published: October 2011

In this letter, we report an important experimental finding and theoretical analysis of the shear-band speed measured in a variety of bulk metallic-glasses. Unlike the prior work, in which the shear-band speed was regarded as a constant, our current study, based on carefully designed loading-holding cyclic tests, reveals that the speed of a shear band correlates with its resultant shear offset. Such a correlation arises as a “size” effect, which could be rationalized with the energy balance principle and shear-banding dynamics entailing initial shear softening and subsequent materials recovery.
GaN directional couplers for integrated quantum photonics
Authors: Zhang Yanfeng , McKnight Loyd , Engin Erman , Watson Ian M. , Cryan Martin J. , Gu Erdan , Thompson Mark G. , Calvez Stephane , O’Brien Jeremy L. , Dawson Martin D.
Published: October 2011

Large cross-section GaN waveguides are proposed as a suitable architecture to achieve integrated quantum photonic circuits. Directional couplers with this geometry have been designed with aid of the beam propagation method and fabricated using inductively coupled plasma etching. Scanning electron microscopy inspection shows high quality facets for end coupling and a well defined gap between rib pairs in the coupling region. Optical characterization at 800 nm shows single-mode operation and coupling-length-dependent splitting ratios. Two photon interference of degenerate photon pairs has been observed in the directional coupler by measurement of the Hong-Ou-Mandel dip [C. K. Hong, et al., Phys. Rev. Lett. 59, 2044 (1987)] with 96% visibility.
Spatial and dietary requirements of the chuditch (Dasyurus geoffroii) in a semiarid climatic zone
Authors: Rayner Kelly , Chambers Brian , Johnson Brent , Morris Keith D. , Mills Harriet R.
Published: October 2011

Knowledge of the ecology of the chuditch (Dasyurus geoffroii) is largely restricted to its distribution in mesic jarrah forests. There is a need for information regarding its ecology in semiarid zones where rainfall and consequently productivity are lower than mesic forests. Given that spatial requirements are strongly influenced by resource availability, it was expected that the chuditch in the semiarid zone would be present at lower densities and would have larger core home ranges (defined by daytime refuges) than those in the jarrah forests. The diet was also investigated by examining the contents of scats. Chuditch at Forrestania were trapped and six individuals were radio-tracked. The population density was one-third that of the lowest estimate reported from the jarrah forest and core home-range estimates were substantially larger, particularly for males. The diet included mammals, birds, reptiles, invertebrates, plants and rubbish, which was consistent with it being a generalist predator. Chuditch did have greater spatial requirements than in the jarrah forest, therefore different management regimes may be needed for populations occurring in the semiarid zone.
Effect of sex and age on temporal variation in the frequency and direction of platypus (Ornithorhynchus anatinus) captures in fyke nets
Authors: Serena Melody , Williams Geoff A.
Published: October 2011

Fyke netting is currently the method mainly used to describe the demographic attributes of platypus (Ornithorhynchus anatinus) populations occupying relatively shallow, flowing water bodies. Based on fieldwork carried out in Victoria from 1995 to 2010, fyke netting surveys conducted in the month when the highest frequency of nightly captures was recorded (July) resulted in nearly three times as many adults and subadults entering nets as compared with those scheduled in the months when the fewest nightly captures were recorded (April and May). Significant sex-specific variation was apparent in relation to monthly capture frequencies: males were captured most often in August (the start of the breeding season), whereas females were captured most often in January (the peak period of lactation). The frequency of platypus captures also varied significantly when considered on a nocturnal time scale, with 63% of adult and subadult captures and 73% of juvenile captures being recorded in the first half of the night. Both juveniles (<11 months) and older animals also showed a significant tendency to travel upstream in the first half of the night. These potential sources of bias in datasets need to be considered when analysing and comparing the results of platypus fyke netting studies.
Mechanical mastication and prescribed fire in conifer - hardwood chaparral: differing responses of ectomycorrhizae and truffles
Authors: Southworth Darlene , Donohue Jessica , Frank Jonathan L. , Gibson Jennifer
Published: October 2011

Fire-prone hardwood–conifer chaparral comprises a significant component of vegetation in seasonally dry areas where prescribed burns of standing vegetation are limited by air-quality restrictions and narrow climatic opportunities for burning. Mechanical mastication is used by land managers to reduce aerial fuels. When burned, the dry masticated slash layer may result in prolonged soil heating, particularly of the upper soil layers, which contain ectomycorrhizal roots and seasonal truffles (hypogeous fungal sporocarps). The purpose of this study was to examine the effects of mechanical mastication followed by prescribed fire on ectomycorrhizae and truffles. We treated blocks with mechanical mastication only, mechanical mastication followed by prescribed fire, prescribed fire only, and no treatment. Five years after the prescribed burn, soils with ectomycorrhizal roots were sampled at the canopy dripline of Pinus attenuata and Quercus kelloggii and surveyed for truffles. Ectomycorrhizae and truffles were described by morphology and by DNA sequences of the internal transcribed spacer region. Ectomycorrhizal communities did not differ among treatments. However, burning reduced the abundance and species richness of truffles in both controls and masticated vegetation. We conclude that prescribed burning of mechanically masticated slash does not harm ectomycorrhizal communities, but does inhibit fruiting of truffles.
Effects of high fire frequency in creosote bush scrub vegetation of the Mojave Desert
Authors: Brooks Matthew L.
Published: October 2011

Plant invasions can increase fire frequency in desert ecosystems where fires were historically infrequent. Although there are many resource management concerns associated with high frequency fire in deserts, fundamental effects on plant community characteristics remain largely unstudied. Here I describe the effects of fire frequency on creosote bush scrub vegetation in the Mojave Desert, USA. Biomass of the invasive annual grass Bromus rubens L. increased following fire, but did not increase further with additional fires. In contrast, density, cover and species richness of native perennial plants each decreased following fire and continued to decrease with subsequent fires, although not as dramatically as after the initial fire. Responses were similar 5 and 14 years post-fire, except that cover of Hymenoclea salsola Torr. & A. Gray and Achnatherum speciosa Trin. & Rupr. both increased in areas burnt once. These results suggest that control of B. rubens may be equally warranted after one, two or three fires, but revegetation of native perennial plants is most warranted following multiple fires. These results are valid within the scope of this study, which is defined as relatively short term vegetation responses (≤14 years) to short fire return intervals (6.3 and 7.3 years for the two and three fire frequency levels) within creosote bush scrub of the Mojave Desert.
Nitric oxide causes root apical meristem defects and growth inhibition while reducing PIN-FORMED 1 (PIN1)-dependent acropetal auxin transport
Authors: Fernández-Marcos María , Sanz Luis , Lewis Daniel R. , Muday Gloria K. , Lorenzo Oscar
Published: October 2011

Nitric oxide (NO) is considered a key regulator of plant developmental processes and defense, although the mechanism and direct targets of NO action remain largely unknown. We used phenotypic, cellular, and genetic analyses in
Arabidopsis thaliana
to explore the role of NO in regulating primary root growth and auxin transport. Treatment with the NO donors S-nitroso-N-acetylpenicillamine, sodium nitroprusside, and S-nitrosoglutathione reduces cell division, affecting the distribution of mitotic cells and meristem size by reducing cell size and number compared with NO depletion by 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO). Interestingly, genetic backgrounds in which the endogenous NO levels are enhanced [chlorophyll a/b binding protein underexpressed 1/NO overproducer 1 (
cue1/nox1
) mirror this response, together with an increased cell differentiation phenotype. Because of the importance of auxin distribution in regulating primary root growth, we analyzed auxin-dependent response after altering NO levels. Both elevated NO supply and the NO-overproducing
Arabidopsis
mutant
cue1/nox1
exhibit reduced expression of the auxin reporter markers
DR5pro:
GUS/GFP
. These effects were accompanied by a reduction in auxin transport in primary roots. NO application and the
cue1/nox1
mutation caused decreased PIN-FORMED 1 (PIN1)-GFP fluorescence in a proteasome-independent manner. Remarkably, the
cue1/nox1
-mutant root phenotypes resemble those of
pin1
mutants. The use of both chemical treatments and mutants with altered NO levels demonstrates that high levels of NO reduce auxin transport and response by a PIN1-dependent mechanism, and root meristem activity is reduced concomitantly.
Fate mapping analysis of lymphoid cells expressing the NKp46 cell surface receptor
Authors: Narni-Mancinelli Emilie , Chaix Julie , Fenis Aurore , Kerdiles Yann M. , Yessaad Nadia , Reynders Ana , Gregoire Claude , Luche Herve , Ugolini Sophie , Tomasello Elena , Walzer Thierry , Vivier Eric
Published: October 2011

NKp46 is a cell surface receptor expressed on natural killer (NK) cells, on a minute subset of T cells, and on a population of innate lymphoid cells that produce IL-22 and express the transcription factor retinoid-related orphan receptor (ROR)-γt, referred to as NK cell receptor (NKR)
+
ROR-γt
+
cells. Here we describe
Nkp46
iCre
knock-in mice in which the gene encoding the improved Cre (iCre) recombinase was inserted into the
Nkp46
locus. This mouse was used to noninvasively trace cells expressing NKp46 in vivo. Fate mapping experiments demonstrated the stable expression of NKp46 on NK cells and allowed a reappraisal of the sequential steps of NK cell maturation. NKp46 genetic tracing also showed that gut NKR
+
ROR-γt
+
and NK cells represent two distinct lineages. In addition, the genetic heterogeneity of liver NK cells was evidenced. Finally,
Nkp46
iCre
mice also represent a unique mouse model of conditional mutagenesis specifically in NKp46
+
cells, paving the way for further developments in the biology of NKp46
+
NK, T, and NKR
+
ROR-γt
+
cells.
Right dislocation in Northern England
Authors: Durham Mercedes
Published: October 2011

The process of right dislocation (RD) has long been recognized in English as a primarily vernacular feature available to speakers of all varieties, but concrete sociolinguistic discussion about its frequency of occurrence and which factors constrain its use are rare. Moreover, English has variants which repeat the operator either before or after the dislocated noun phrase (NP) or pronominal particle, e.g. She’s got a very good degree has Julie, which makes it unlike most of the languages with comparable RD forms. These variants are either ignored completely in RD literature or considered on their own. The present analysis aims, therefore, to provide a holistic view of RD strategies. Starting with a classification of the various RD strategies used in the North of England, where this variant is most often reported to be found, this paper will present a quantitative analysis of RD in a corpus of York speech. The analysis will demonstrate that, while RD forms are used by York speakers (young and old, male and female), with respect to overall frequency RD is in fact far more rare than reports make it out to be, and that its social distribution is rather unexpected in some respects.
Bricolage assembling
Authors: Santamaría García Carmen
Published: October 2011

This article illustrates the use of spoken corpora for a contrastive study of casual conversation in English and Spanish. It models an eclectic methodology for cross-linguistic comparison at the level of discourse, specifically of exchange structures, by drawing upon analytic resources from corpus linguistics (CL), conversation analysis (CA) and discourse analysis (DA). This combination of perspectives presents challenges and limitations which will be discussed and exemplified through a case study that explores agreement and disagreement sequences. English data have been retrieved from the Santa Barbara Corpus of Spoken American English (SBCSAE; cf. Du Bois et al. 2000, 2003) and Spanish data from Corpus Oral de Referencia del Español Contemporáneo (CORLEC). The case study reveals the need for spoken corpora to include complete conversations, discourse annotation, sound files and detailed contextual information. This means a step forward from corpora of spoken language to discourse corpora and a challenge for CL, CA and DA in the near future.
Attitudes to Arabic language policies in Israel
Authors: Yitzhaki Dafna
Published: October 2011

The paper reports the findings of a survey study which examined attitudes towards a range of language policies for the Arabic language in Israel. Arabic is an official language in Israel as a result of a Mandatory Order (1922) which dictates comprehensive Hebrew-Arabic bilingual conduct by state authorities. In practice, Arabic’s public position in Israel is marginal, and Hebrew is the dominant language in Israeli public spheres. Arabic speakers, a national indigenous minority, and Jewish immigrants from the Former Soviet Union, form the two largest language-minority groups in Israel. The study explored attitudes concerning (1) the use of Arabic in three public domains (government services, public television, and teaching of Arabic in Jewish schools), (2) a Hebrew-Arabic bilingual model, and (3) a multilingual model addressing language minorities in Israel in general. Respondents were 466 university and college students, Jews and Arabs, divided into five subgroups along linguistic, ethnic and religious lines. The main findings indicated (1) a clear hierarchy of language policy domains among all five subgroups, with ‘government services’ being the most favored domain; (2) a tendency among Jewish respondents to favor a multilingual policy over a Hebrew-Arabic bilingual one; and (3) a language minority element (non-native Hebrew speakers), overshadowed by the ethnic-religious (Jewish-Arab) element.
The native-non-native dichotomy in minority language contexts
Authors: O'Rourke Bernadette , Ramallo Fernando F.
Published: October 2011

In minority language contexts, the aim of language policy and planning initiatives is frequently to enhance their survival prospects by increasing individuals’ knowledge and use of such languages in a variety of social contexts. The success of such policies depends on a variety of factors. These include the ability of policy to encourage maintenance of the language amongst existing speakers (the so-called ‘native’ speakers of the language) and its revival amongst individuals in the community who no longer speak it and who have become ‘native’ speakers of another language, typically, the dominant language. However, the task of policy makers and language planners is often made more difficult by sociolinguistic, socio-economic, socio-geographical and ideological differences between ‘native’ speakers and ‘non-native’ newcomers to the language. Rather than forming a unified speech community, ‘native’ and ‘non-native’ speakers of the minority language very often see themselves as being socially and linguistically incompatible. The purpose of this article is to examine the native-non-native dichotomy in two minority language contexts: Irish in the Republic of Ireland and Galician in the Autonomous Community of Galicia.
Antonymy
Authors: Paradis Carita , Willners Caroline
Published: October 2011

This article offers a Cognitive Semantic approach to antonymy in language and thought. Based on a series of recent empirical investigations using different observational techniques, we analyze (i) the nature of the category of antonymy, and (ii) the status of its members in terms of goodness of opposition. Our purpose is to synthesize these empirical investigations and provide a theoretical framework that is capable of accounting for antonymy as a mode of thought in language use and meaning-making. We show that antonymy has conceptual basis, but in contrast to other lexico-semantic construals, a limited number of words seem to have special lexical status as dimensional protagonists. Form–meaning pairings are antonyms when they are used as binary opposites. Configurationally, this translates into a construal where some content is divided by a BOUNDARY. This configuration (or schema) is a necessary requirement for meanings to be used as antonyms and all antonyms have equal status as members. In contrast to categorization by configuration, categorization by contentful meaning structures forms a continuum ranging from strongly related pairings as core members to ad hoc couplings on the outskirts. In order to explain why some lexico-semantic couplings tend to form conventionalized pairs, we appeal to their ontological set-up, the symmetry of the antonyms in relation to the boundary between the meaning structures, their contextual range of use and frequency.
Francesco Crispi's relationship with Britain: from admiration to disillusionment
Authors: Duggan Christopher
Published: October 2011

This article examines the changing attitude of the Sicilian statesman Francesco Crispi towards Britain between the 1850s and the end of the century. While Crispi had enormous admiration for Britain, and recognised that Italy had much to learn from its political system, he also acknowledged that the British constitution was the product of a long process of historical evolution and could never be imitated slavishly in Italy. From the end of the 1870s in particular, Crispi felt that Italy could not concede the degree of freedom permitted in Britain until the state had completed its work of what he called ‘political education’. As prime minister in the 1880s and 1890s Crispi looked to an aggressive foreign policy to strengthen Italy's beleaguered institutions, and he counted on British support to achieve this. The refusal of Britain to back him in the way he hoped left him perplexed and ultimately disillusioned about what he had felt was a special friendship between the two countries.
The Centre for the Advanced Study of Italian Society at Reading
Authors: Woolf Stuart
Published: October 2011

The Centre for the Advanced Study of Italian Society was created by Stuart Woolf at Reading University in 1966. It provided the institutional basis for close collaboration with Italian academics and politicians, many of whom participated in seminars. It attracted funding from Italy for research collaboration with Italian academics. The presence of the Centre led to donations from English antifascists of books and archives, and to the acquisition by the University Library of a major Italian private library on post-unity Italian history and culture.
Technology development and mass production of Nb3Sn conductors for ITER toroidal field coils in Japan
Authors: Takahashi Y. , Isono T. , Hamada K. , Nunoya Y. , Nabara Y. , Matsui K. , Hemmi T. , Kawano K. , Koizumi N. , Oshikiri M. , Uno Y. , Tsutsumi F. , Yoshikawa M. , Nakajima H. , Okuno K. , Devred A. , Mitchell N.
Published: October 2011

The design and manufacture of Nb3Sn conductors for ITER toroidal field (TF) coils have many technical challenges. Although it was demonstrated in the ITER model coil project that the conductors have a sufficiently high performance and the engineering design is valid, unexpected issues arose. Through both theoretical and experimental efforts improved conductors were developed. The Japan Atomic Energy Agency started to procure improved conductors for TF coils as part of the ITER project. Because the required tonnage of Nb3Sn strands is quite large compared with past experience and the required superconducting performance is higher than that of the model coils, quality control techniques are very important for the successful manufacture of the strands. Approximately 60 ton of Nb3Sn strands have been successfully completed under a severe quality control regimen and all strands meet ITER specifications. This paper summarizes the technical developments leading to the first successful mass production of ITER TF conductors.
Impact of diuretic dosing on mortality in acute heart failure using a propensity‐matched analysis
Authors: Yilmaz Mehmet Birhan , Gayat Etienne , Salem Reda , Lassus Johan , Nikolaou Maria , Laribi Said , Parissis John , Follath Ferenc , Peacock W. Franck , Mebazaa Alexandre
Published: October 2011

Aims

Loop diuretics are recommended to treat congestion in heart failure (HF), despite limited quality evidence. High‐dose (HD) loop diuretics seem to worsen outcomes in chronic HF, though; data for acute HF are scarce, with equivocal results.

Methods and results

The ALARM‐HF study recorded in‐hospital HF therapy in 4953 patients from nine countries. A post‐hoc analysis was performed to determine if there was an interaction between intravenous (iv) bolus diuretic dosing and outcomes. Patients were classified as receiving high‐ or low‐dose iv furosemide if their total initial 24 h dose was above (HD) or below [low dose (LD)] 1 mg/kg. Propensity scoring, matching an extensive list of variables, was performed. High‐dose and LD patients were matched by propensity scores and outcomes determined. We identified 2460 LD and 848 HD patients, with overall in‐hospital mortality of 9 and 13% (P= 0.002), respectively. After propensity matching, there were 506 patients in each subgroup, with the matched LD and HD cohorts having similar mortality (13 vs. 15%; P= 0.4). We further investigated in which subgroups of patients HD diuretics influenced mortality. Before matching, HD diuretics were associated with a greater risk of in‐hospital death in some subgroups, including patients aged >80 years, those with an acute coronary syndrome, or with a left ventricular ejection fraction <40%. However, after propensity score matching, no association was found between diuretic dosing and death in any of the studied subgroups.

Conclusions

In the initial management of acute HF, HD iv diuretics, per se, do not influence short‐term mortality.
A Showcase of Bench-to-Bedside Regenerative Medicine at the 2010 ASNTR
Authors: Eve David J. , Borlongan Cesar V. , Sanberg Paul R.
Published: October 2011

Insight into the expanding themes of regenerative medicine is provided by the American Society for Neural Therapy and Repair's annual meeting. The 17th meeting covered a wide range of neurodegenerative disorders, exploring methods to elucidate the currently unknown mechanisms behind the disorders, as well as possible treatments ranging from the use of growth factors, gene therapy to cell transplantation. The importance of growth factors, both as a contributing factor to a disease and as a possible treatment either solo, or as a consequence of, or in conjunction with, stem cell therapy, was highlighted. The potential for viral vectors was also explored either for cells prior to transplantation or as a direct treatment regime into the brain itself. Identification of biomarkers that would allow early detection of a disease is an important factor in our fight against disease. The ability to now perform whole genome analysis and biomolecular profiling provides hope that such markers could be identified which not only could identify this likely to suffer from a disorder but also could allow its progress to be monitored. A few preclinical and clinical cell transplantation trials were also introduced as potential areas of followup in the years to come.
The Three-Layer Concentric Model of Glioblastoma: Cancer Stem Cells, Microenvironmental Regulation, and Therapeutic Implications
Authors: Persano Luca , Rampazzo Elena , Della Puppa Alessandro , Pistollato Francesca , Basso Giuseppe
Published: October 2011

Tumors arising in the central nervous system are thought to originate from a sub-population of cells named cancer stem cells (CSCs) or tumor initiating cells (TICs) that possess an immature phenotype, combined with self-renewal and chemotherapy resistance capacity. Moreover, in the last years, these cells have been identified in particular brain tumor niches fundamental for supporting their characteristics. In this paper, we report studies from many authors demonstrating that hypoxia or the so called “hypoxic niche” plays a crucial role in controlling CSC molecular and phenotypic profile. We recently investigated the relationship existing between Glioblastoma (GBM) stem cells and their niche, defining the theory of three-concentric layers model for GBM mass. According to this model, GBM stem cells reside preferentially within the hypoxic core of the tumour mass, while more differentiated cells are mainly localized along the peripheral and vascularized part of the tumour. This GBM model provides explanation of the effects mediated by the tumour microenvironment on the phenotypic and molecular regulation of GBM stem cells, describing their spatial distribution in the tumor bulk. Moreover, we discuss the possible clinical implications of the creation of this model for future GBM patient management and novel therapeutic strategies development.
Single Cystathionine β-Synthase Domain–Containing Proteins Modulate Development by Regulating the Thioredoxin System in Arabidopsis
Authors: Yoo Kyoung Shin , Ok Sung Han , Jeong Byung-Cheon , Jung Kwang Wook , Cui Mei Hua , Hyoung Sujin , Lee Myeong-Ryeol , Song Hyun Kyu , Shin Jeong Sheop
Published: October 2011

Plant thioredoxins (Trxs) participate in two redox systems found in different cellular compartments: the NADP-Trx system (NTS) in the cytosol and mitochondria and the ferredoxin-Trx system (FTS) in the chloroplast, where they function as redox regulators by regulating the activity of various target enzymes. The identities of the master regulators that maintain cellular homeostasis and modulate timed development through redox regulating systems have remained completely unknown. Here, we show that proteins consisting of a single cystathionine β-synthase (CBS) domain pair stabilize cellular redox homeostasis and modulate plant development via regulation of Trx systems by sensing changes in adenosine-containing ligands. We identified two CBS domain–containing proteins in Arabidopsis thaliana, CBSX1 and CBSX2, which are localized to the chloroplast, where they activate all four Trxs in the FTS. CBSX3 was found to regulate mitochondrial Trx members in the NTS. CBSX1 directly regulates Trxs and thereby controls H2O2 levels and regulates lignin polymerization in the anther endothecium. It also affects plant growth by regulating Calvin cycle enzymes, such as malate dehydrogenase, via homeostatic regulation of Trxs. Based on our findings, we suggest that the CBSX proteins (or a CBS pair) are ubiquitous redox regulators that regulate Trxs in the FTS and NTS to modulate development and maintain homeostasis under conditions that are threatening to the cell.
Assessment of the pharmacology and tolerability of PF‐04457845, an irreversible inhibitor of fatty acid amide hydrolase‐1, in healthy subjects
Authors: Li Gai Ling , Winter Helen , Arends Rosalin , Jay Gary W. , Le Vu , Young Tim , Huggins John P.
Published: November 2011

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

• Inhibition of fatty acid amide hydrolase‐1 (FAAH1) and the subsequent elevation of fatty acid amides has been proposed as a strategy to induce the analgesic properties of cannabinoids without the accompanying negative side effects such as impairment in cognition, motor control and predisposition to psychoses. PF‐04457845 is a potent and selective irreversible FAAH1 inhibitor which has been shown to elevate fatty acid amide concentrations in animal models and induce responses in behavioural models suggestive of analgesia.

WHAT THIS STUDY ADDS

• This study is the first to investigate a FAAH1 inhibitor in humans. PF‐04457845 is well tolerated following single and multiple dosing to healthy volunteers and has pharmacokinetic and pharmacodynamic properties that make nearly complete inhibition of FAAH1 possible with once daily dosing.

AIMS To evaluate the pharmacology and tolerability of PF‐04457845, an orally available fatty acid amide hydrolase‐1 (FAAH1) inhibitor, in healthy subjects.

METHODS

Double‐blind, randomized, placebo‐controlled single and multiple rising dose studies and an open‐label, randomized, food effect study were conducted. Plasma and urine PF‐04457845 concentrations, plasma fatty acid amide concentrations and FAAH1 activity in human leucocytes were measured. Tolerability, including effects on cognitive function, were assessed.

RESULTS

PF‐04457845 was rapidly absorbed (median tmax 0.5–1.2 h). Exposure increased supraproportionally to dose from 0.1 to 10 mg and proportionally between 10 and 40 mg single doses. The pharmacokinetics appeared dose proportional following 14 days once daily dosing between 0.5 and 8 mg. Steady‐state was achieved by day 7. Less than 0.1% of the dose was excreted in urine. Food had no effect on PF‐04457845 pharmacokinetics. FAAH1 activity was almost completely inhibited (>97%) following doses of at least 0.3 mg (single dose) and 0.5 mg once daily (multiple dose) PF‐04457845. Mean fatty acid amide concentrations increased (3.5‐ to 10‐fold) to a plateau and then were maintained following PF‐04457845. FAAH1 activity and fatty acid amide concentrations returned to baseline within 2 weeks following cessation of dosing at doses up to 4 mg. There was no evidence of effects of PF‐04457845 on cognitive function. PF‐04457845, at doses up to 40 mg single dose and 8 mg once daily for 14 days, was well tolerated.

CONCLUSIONS

PF‐04457845 was well tolerated at doses exceeding those required for maximal inhibition of FAAH1 activity and elevation of fatty acid amides.
Wave‐equation migration with dithered plane waves
Authors: Perrone Francesco , Sava Paul
Published: October 2011

Wave‐equation based shot‐record migration provides accurate images but is computationally expensive because every shot must be migrated separately. Shot‐encoding migration, such as random shot‐encoding or plane‐wave migration, aims to reduce the computational cost of the imaging process by combining the original data into synthesized common‐source gathers. Random shot‐encoding migration and plane‐wave migration have different and complementary features: the first recovers the full spatial bandwidth of the image but introduces strong artefacts, which are due to the interference between the different shot wavefields; the second provides an image with limited spatial detail but is free of crosstalk noise. We design a hybrid scheme that combines linear and random shot‐encoding in order to limit the drawbacks and merge the advantages of these two techniques. We advocate mixed shot‐encoding migration through dithering of plane waves. This approach reduces the crosstalk noise relative to random shot‐encoding migration and increases the spatial bandwidth relative to conventional plane‐wave migration when the take‐off angle is limited to reduce the duration of the plane‐wave gather. In turn, this decreases the migration cost. Migration with dithered plane waves operates as a hybrid encoding scheme in‐between the end members represented by plane‐wave migration and random shot‐encoding. Migration with dithered plane waves has several advantages: every synthesized common‐source gather images in a larger aperture, the crosstalk noise is limited and higher spatial resolution is achievable compared to shot‐record migration, random shot‐encoding and linear shot‐encoding, respectively. Computational cost is also reduced relative to both random and linear shot‐encoding migration since fewer synthesized common‐source gathers are necessary to obtain a high signal‐to‐noise ratio and high spatial resolution in the final image.
Photosynthesis and productivity in heterogeneous arctic tundra: consequences for ecosystem function of mixing vegetation types at stand edges
Authors: Fletcher Benjamin J. , Gornall Jemma L. , Poyatos Rafael , Press Malcolm C. , Stoy Paul C. , Huntley Brian , Baxter Robert , Phoenix Gareth K.
Published: October 2011

1. Arctic vegetation tends to be spatially heterogeneous and can have large areas of mixed ‘transition zone’ vegetation between stands dominated by a single or few species. If plant photosynthesis and growth within these transition zones differs significantly from main vegetation stands, and if transition zones are not considered when extrapolating stand‐level findings to larger scales in space, then transition zones will provide considerable error to landscape‐level estimates of gross primary productivity (GPP).

2. In a heterogeneous sub‐Arctic tundra landscape, we undertook a detailed assessment of plant and ecosystem photosynthesis and plant growth in stands dominated by the short‐stature evergreen dwarf shrub Empetrum hermaphroditum, the deciduous dwarf shrub Betula nana, the taller deciduous shrub Salix glauca and also the transition zones between them.

3. Our findings show that plants in transition zones towards taller and more productive vegetation types frequently showed reduced shoot growth, equal or reduced light‐saturated photosynthesis (Pmax) and other typical shade responses (e.g. increased leaf chlorophyll and leaf area per mass) when compared with conspecific plants in main stands where the species is dominant. Critically, whole‐ecosystem GPP per leaf area was 20–40% lower in transition zones than in main vegetation stands as a consequence. A modelling analysis suggests that the under‐productivity of some transition zones results from the lack of a clear ‘winner’ in the competition for light, such that active leaves of some species are shaded by relatively inactive leaves of others.

4. These findings highlight how biotic interactions can considerably influence plant performance to the extent that productivity of mixed vegetation (transition zones) cannot be predicted from their main stands either side. How the consequences of mixing vegetation relate to mechanisms in biodiversity‐function theory is discussed.

5. Synthesis: Our work shows that the productivity of transition zones of arctic vegetation is considerably lower than may be estimated from the main stands on either side. This reduced GPP in transition zones, therefore, must be considered when modelling carbon fluxes at the landscape scale and suggests that the impact of transition zones on ecosystem function needs further investigation in heterogeneous landscapes, where they make up a significant proportion of the land cover.