bluuebunny/crossref_metadata_2025 huggingface dataset:
Self-consistent electron transport in tokamaks
Authors: Gatto R. , Chavdarovski I.
Published: September 2007

Electron particle, momentum, and energy fluxes in axisymmetric toroidal devices are derived from a version of the action-angle collision operator that includes both diffusion and drag in action-space [D. A. Hitchcock, R. D. Hazeltine, and S. M. Mahajan, Phys. Fluids 26, 2603 (1983); H. E. Mynick, J. Plasma Phys. 39, 303 (1988)]. A general result of the theory is that any contribution to transport originating directly from the toroidal frequency of the particle motion is constrained to be zero when the electron temperature is equal to the ion temperature. In particular, this constraint applies to those components of the particle and energy fluxes that are proportional to the magnetic shear, independent of the underlying turbulence and of whether the particles are trapped or untrapped. All the total fluxes describing collisionless transport of passing electrons in steady-state magnetic turbulence contain contributions proportional to the conventional thermodynamic drives, which are always outward, and contributions proportional to the magnetic shear, which have both magnitude and sign dependent on the ion-electron temperature ratio. The turbulent generalization of Ohm’s law includes a hyper-resistive term, which flattens the current density profile on a fast time scale, and a turbulent electric field, which can have both signs depending on the electron-ion temperature ratio.
Influence of elastic scattering of photoelectrons on angle-resolved x-ray photoelectron spectroscopy
Authors: Kimura Kenji , Nakajima Kaoru , Conard Thierry , Vandervorst Wilfried
Published: September 2007

The validity of the electron effective attenuation length database developed by National Institute of Standards and Technology (NIST) is examined for x-ray photoelectron spectroscopy (XPS) measurement of HfO2 (2.7nm)∕SiON (0.8nm)∕Si. The angular dependences of photoelectron yields are calculated using the NIST database and composition depth profiles measured by high-resolution Rutherford backscattering spectroscopy. The calculated result reproduces the observed XPS result fairly well even at larger emission angles up to 80°, indicating that the accuracy of XPS depth profiling can be improved using the NIST database.
Band structures of AlAs, GaP, and SiGe alloys: A 30 k×p model
Authors: Fraj N. , Saïdi I. , Ben Radhia S. , Boujdaria K.
Published: September 2007

The band structure of indirect-band gap semiconductors (AlAs, GaP) as well as indirect-band gap alloys semiconductors (GeSi) is described theoretically by using a 30×30 k×p model including the d far-level contribution. For all materials investigated, the resulting electronic band structure parameters are in good agreement with experimental values. The method also provides a good description of the second conduction band which is useful for transport modeling. Finally, our results show that Luttinger parameters, the κ valence band parameter, and the effective masses in the X and L valleys are in good agreement with available experimental data.
High pressure photoluminescence of CdZnSe quantum dots: Alloying effect
Authors: Zhao Zhi , Zeng Jie , Ding Zejun , Wang Xiaoping , Hou Jianguo , Zhang Zengming
Published: September 2007

The pressure dependence of photoluminescence of wurtzite 5.5nm CdZnSe alloy quantum dots (QDs) was studied and compared with that of the wurtzite 3.5nm CdSe QDs. The direct Γ energy gaps of wurtzite QDs were found to increase with the pressure, and the pressure coefficients were gained as 35.4meV∕GPa for CdZnSe and 28.4meV∕GPa for CdSe QDs. The authors attributed the high value of pressure coefficient for CdZnSe alloy QDs to the alloying effect with strengthening the anion-cation s-s orbital coupling and weakening p-d orbital coupling in the alloy. The result demonstrates that the alloying process has a dominant role in the electronic state and structure transition under high pressure.
Enhanced tunable Bragg diffraction in large-pore inverse opals using dual-frequency liquid crystal
Authors: Graugnard E. , Dunham S. N. , King J. S. , Lorang D. , Jain S. , Summers C. J.
Published: September 2007

Large-pore TiO2 inverse opals were fabricated by atomic layer deposition in sintered polystyrene colloidal crystal templates and infiltrated with dual-frequency liquid crystal. The optical properties of the hybrid organic/inorganic structure were characterized by reflectance measurements of the Bragg peak, the position of which was tuned using a frequency dependent applied electric field. A 6nm blueshift was observed for frequencies less than 13kHz and a 13nm redshift for frequencies above 13kHz. These results demonstrate enhanced optical tunability in three-dimensional photonic crystals and are important for the development of active photonic devices.
Proximity effects induced by a gold layer on La0.67Sr0.33MnO3 thin films
Authors: Bertacco R. , Brivio S. , Cantoni M. , Cattoni A. , Petti D. , Finazzi M. , Ciccacci F. , Sidorenko A. A. , Ghidini M. , Allodi G. , De Renzi R.
Published: September 2007

The authors report about La0.67Sr0.33MnO3 single crystal manganite thin films in interaction with a gold capping layer. With respect to uncoated manganite layers of the same thickness, Au-capped 4nm thick manganite films reveal a dramatic reduction (≃185K) of the Curie temperature TC and a lower saturation low temperature magnetization M0. A sizable TC reduction (≃60K) is observed even when an inert SrTiO3 layer is inserted between the gold film and the 4nm thick manganite layer, suggesting that this effect might have an electrostatic origin.
Electronic transport characterization of AlGaN∕GaN heterostructures using quantitative mobility spectrum analysis
Authors: Lisesivdin S. B. , Yildiz A. , Acar S. , Kasap M. , Ozcelik S. , Ozbay E.
Published: September 2007

Resistivity and Hall effect measurements in nominally undoped Al0.25Ga0.75N∕GaN heterostructures grown on sapphire substrate by metal-organic chemical vapor deposition are carried out as a function of temperature (20–350K) and magnetic field (0–1.5T). The measurement results are analyzed using the quantitative mobility spectrum analysis techniques. It is found that there is strong two-dimensional electron gas localization below 100K, while the thermally activated minority carriers with the activation energies of ∼58 and ∼218meV contribute to the electron transport at high temperatures.
Fine Group Gradings of the Real Forms of sl(4,C), sp(4,C), and o(4,C)
Authors: Patera Jiří , Pelantová Edita , Svobodová Milena
Published: September 2007

We present an explicit description of the “fine group gradings” (i.e., group gradings which cannot be further refined) of the real forms of the semisimple Lie algebras sl(4,C), sp(4,C), and o(4,C). All together 12 real Lie algebras are considered, and a total of 44 of their fine group gradings are listed. The inclusions sl(4,C)⊃sp(4,C)⊃o(4,C) are an important tool in our presentation. Systematic use is made of the faithful representations of the three Lie algebras by 4×4 matrices.
Incomplete Kochen-Specker coloring
Authors: Granström Helena
Published: September 2007

A particular incomplete Kochen-Specker coloring, suggested by Appleby [Stud. Hist. Philos. Mod. Phys. 36, 1 (2005)] in dimension three, is generalized to arbitrary dimension. We investigate its effectivity as a function of dimension, using two different measures. A limit is derived for the fraction of the sphere that can be colored using the generalized Appleby construction as the number of dimensions approaches infinity. The second, and physically more relevant measure of effectivity, is to look at the fraction of properly colored ON bases. Using this measure, we derive a “lower bound for the upper bound” in three and four real dimensions.
Periodic surface structures on gallium phosphide after irradiation with 150fs–7ns laser pulses at 800nm
Authors: Hsu E. M. , Crawford T. H. R. , Tiedje H. F. , Haugen H. K.
Published: September 2007

Gallium phosphide is irradiated with 150fs–7ns duration laser pulses at a wavelength of 800nm. After irradiation with 150fs pulses, periodic surface structures (ripples) are observed on the GaP surface, exhibiting near-wavelength and substantially subwavelength spatial periods depending on irradiation conditions. As the pulse duration increases, near-wavelength ripples become a more dominant feature, completely replacing subwavelength ripples for pulse lengths beyond 80–130ps. Overall the results show that subwavelength ripples can be generated for a wide range of pulse durations, and their formation is quite insensitive to pulse intensity.
Lateral electron tunneling through single self-assembled InAs quantum dots coupled to superconducting nanogap electrodes
Authors: Shibata Kenji , Buizert Christo , Oiwa Akira , Hirakawa Kazuhiko , Tarucha Seigo
Published: September 2007

The authors have fabricated superconductor-quantum dot-superconductor (SC-QD-SC) junctions by using SC aluminum electrodes with narrow gaps laterally contacting a single self-assembled InAs QD. The fabricated junctions exhibited clear Coulomb staircases and Coulomb oscillations at 40mK. Furthermore, clear suppression in conductance was observed for the source-drain voltage, ∣VSD∣<2Δ∕e, where Δ is the SC energy gap of Al. The absence of Josephson current that flows through QDs is due to the strong Coulomb interaction and non-negligible thermal fluctuation in our measurement system.
Defect engineering by surface chemical state in boron-doped preamorphized silicon
Authors: Yeong S. H. , Srinivasan M. P. , Colombeau Benjamin , Chan Lap , Akkipeddi Ramam , Kwok Charlotte T. M. , Vaidyanathan Ramakrishnan , Seebauer Edmund G.
Published: September 2007

The continual downscaling of silicon devices for integrated circuits requires the formation of pn junctions that are progressively shallower, incorporate increasing levels of electrically active dopant, and sustain minimal implantation damage. In the case of boron implanted into preamorphized Si, the authors show that all these goals can be accomplished simultaneously through the use of an atomically clean surface, which during annealing acts as a large sink that removes Si interstitials selectively over dopant interstitials.
418
cm
−
1
Raman scattering from gallium nitride nanowires: Is it a vibration mode of N-rich Ga–N bond configuration?
Authors: Ning J. Q. , Xu S. J. , Yu D. P. , Shan Y. Y. , Lee S. T.
Published: September 2007

A Raman-active vibration mode at 418cm−1 is observed in wurtzite gallium nitride (GaN) nanowires synthesized by different growth methods. In particular, Raman scattering measurements of a number of GaN nanowires systematically prepared by nitriding β-Ga2O3 nanowires at different temperatures show an interesting evolution of the mode, revealing that it is most likely the vibration mode of N-rich octahedral Ga–N6 bonds. This idea is further supported by the high-resolution transmission electron microscopic observation.
Asymptotic expansion of the log-partition function for a gas of interacting Brownian loops
Authors: Poghosyan Suren , Zessin Hans
Published: September 2007

The asymptotic behavior of the logarithm of the grand partition function of a quantum gas in the Feynman-Kac representation is studied. Under suitable restrictions on the stable pair potential the log-partition function is expanded at low activity as the domain is dilated to the infinity. The volume and the boundary terms are given explicitly as functional integrals. The proof is based on the cluster expansion method.
Organic field effect transistors with dipole-polarized polymer gate dielectrics for control of threshold voltage
Authors: Sakai Heisuke , Takahashi Yoshikazu , Murata Hideyuki
Published: September 2007

The authors demonstrate organic field effect transistors (OFETs) with a dipole-polarized polyurea for the gate dielectrics. In the dielectrics, the internal electric field induces the mobile charge carrier in the semiconductor layer to the semiconductor-dielectric interface. OFETs with dipole-polarized gate dielectrics exhibit lower threshold voltage. With nonpolarized gate dielectrics, the threshold voltage was −11.4V, whereas that decreased to −5.3V with polarized gate dielectrics. In addition to the threshold voltage, polarized gate dielectrics reduced subthreshold swing from 4.1to2.4V/decade at the gate voltage of −20V. These results show that dipole-polarized polyurea gate dielectrics allow us to operate OFETs with lower power consumption.
ZnO light-emitting diodes fabricated on Si substrates with homobuffer layers
Authors: Ye Z. Z. , Lu J. G. , Zhang Y. Z. , Zeng Y. J. , Chen L. L. , Zhuge F. , Yuan G. D. , He H. P. , Zhu L. P. , Huang J. Y. , Zhao B. H.
Published: September 2007

ZnO homojunction light-emitting diodes (LEDs), comprised of N–Al codoped p-type ZnO and Al-doped n-type ZnO layers, were fabricated on Si substrates with homobuffer layers. The current-voltage measurements showed typical diode characteristic with a threshold voltage of about 3.3V. The electroluminescence (EL) bands at 110K consisted of a near-band-edge emission at 3.18eV and a deep level emission at 2.58eV. The EL emissions were assigned as radiative recombinations, presumably of donor-acceptor pairs, in the p-type layer of the LED. The quenching of EL with temperature was attributed to the degradation of p-type conducting of the ZnO:(N,Al) layer.
Enhanced electroluminescence efficiency of oxidized amorphous silicon nitride light-emitting devices by modulating Si∕N ratio
Authors: Huang Rui , Chen Kunji , Dong Hengping , Wang Danqing , Ding Honglin , Li Wei , Xu Jun , Ma Zhongyuan , Xu Ling
Published: September 2007

The authors had reported green-yellow electroluminescence (EL) from N-rich oxidized amorphous silicon nitride (a-SiN:O) light-emitting devices (LEDs) in a previous work. In this work, a significantly enhanced EL intensity was obtained in the LED by employing Si-rich a-SiN:O instead of N-rich a-SiN:O as luminescent active layer. Moreover, the Si-rich a-SiN:O devices also exhibit lower turn-on voltage and the external quantum efficiency is found to be three times higher than that of the N-rich a-SiN:O devices. The electrical characteristics analyses reveal that the injection barrier for Si-rich a-SiN:O devices is reduced by 30% compared to that of N-rich a-SiN:O devices, which results in a remarkably enhanced carrier-injection efficiency and gives rise to the notable improved performances of the LEDs.
Manipulation of spin states by dipole polarization switching
Authors: Kim Nammee , Kim Heesang , Kang T. W.
Published: September 2007

A ferromagnetic/ferroelectric hybrid double quantum disk structure is proposed, capable of manipulating spin states. Switching of spontaneous electric polarization of the ferroelectric quantum disk changes the potential profile of the system and induces ground state transition. Two carrier spin states are separated into ferroelectric semiconductor and diluted magnetic semiconductor disks via asymmetric Zeeman splitting of the coupled quantum disks. The proof of the spin separation resulting from the dipole polarization switching is shown by the probability density change of the lowest energy subband. Evolution of the spin state is also predicted from the subband energy diagram as a function of the bias voltage.
Influence of photonic nanotexture on the light extraction efficiency of GaN
Authors: Tian L. , Stojanovic N. , Song D. Y. , Bernussi A. A. , Berg J. M. , Holtz M.
Published: September 2007

The authors report the effects of nanoscale texturing on the optical properties of GaN. The texture consists of circular holes etched in a hexagonal array with 1μm spacing. Hole diameters range from 120to700nm and depths range up to 1μm. The optical properties are studied using cathodoluminescence (CL) measurements in a scanning electron microscope. Intensity is found to increase with pore diameter, an effect they attribute to changes in the optical extraction efficiencies. A systematic redshift observed in the CL peak is attributed to local relaxation of the compressive stress present in the starting GaN epilayer.
Attention to Configural Information in Change Detection for Faces
Authors: Favelle Simone K , Burke Darren
Published: September 2007

In recent research the change-detection paradigm has been used along with cueing manipulations to show that more attention is allocated to the upper than lower facial region, and that this attentional allocation is disrupted by inversion. We report two experiments the object of which was to investigate how the type of information changed might be a factor in these findings by explicitly comparing the role of attention in detecting change to information thought to be ‘special’ to faces (second-order relations) with information that is more useful for basic-level object discrimination (first-order relations). Results suggest that attention is automatically directed to second-order relations in upright faces, but not first-order relations, and that this pattern of attentional allocation is similar across features.
Diet of a native carnivore, the spotted-tailed quoll (Dasyurus maculatus), before and after an intense wildfire
Authors: Dawson James P. , Claridge Andrew W. , Triggs Barbara , Paull David J.
Published: September 2007

The relationship between the diet of the spotted-tailed quoll (Dasyurus maculatus) and the abundance of its prey was investigated in rain-shadow woodland habitat in southern New South Wales for one year before and two years after a high-intensity, broad-scale wildfire. Scats were variously collected from quoll latrines and live-trapped animals during winter for each of the three years and analysed to determine prey items. Estimates of abundance of key ground-dwelling and arboreal medium-sized mammals were simultaneously obtained using plot-based survey techniques and spotlighting. Over the duration of the study, quoll diet was dominated by medium-sized mammals, particularly brushtail possums (Trichosurus spp.) and lagomorphs (rabbit and hare), followed by small and large-sized mammals. After the fire there was a shift in utilisation of food resources in response to significant changes in prey availability. Monitoring revealed that brushtail possums, lagomorphs and bandicoots were all significantly less abundant in the winter following the fire, and populations of lagomorphs, but not possums, then increased in the second winter after the fire. Quolls adapted to this by taking significantly more lagomorphs in each of the two years after the fire and by taking advantage of a short-term increase in the availability of carrion. The results of this study reaffirm that the spotted-tailed quoll is adaptable in its utilisation of available food, and that fires are not necessarily detrimental to the species and its prey base.
Does vegetation cover affect the rate of capture of ground-active lizards in pitfall traps?
Authors: Schlesinger Christine A.
Published: September 2007

Pitfall traps are commonly used to capture terrestrial vertebrates, but it is not known whether differences in vegetation structure affect the efficiency of these traps. Studies that investigate the effects of fire, grazing or vegetation rehabilitation on faunal populations usually compare sites that differ in vegetation structure and the validity of using pitfall traps to sample populations under these circumstances is open to question. This study tests whether vegetation structure affects the rate at which lizards are captured in pitfall traps by cutting ground vegetation in a controlled experiment conducted in field enclosures. The study was undertaken in an area of mulga (Acacia aneura) shrubland in central Australia. Ground cover, consisting of grasses and forbs, was reduced from ~27% to 10% in treatment enclosures. These levels of cover correspond broadly to the range of ground covers encountered in this habitat, including areas with high and low levels of grazing. No difference was detected in the rate at which lizards were captured in enclosures where grass was cut compared with the control enclosures or rates of capture before grass was cut. These results indicate that pitfall trapping is a valid technique for comparing lizard populations in arid mulga shrublands within the range of vegetation covers used in this study, including areas that are subject to different levels of grazing.
Acoustic attractants enhance trapping success for cane toads
Authors: Schwarzkopf L. , Alford R. A.
Published: September 2007

Cane toads are an introduced pest in many tropical locations around the world, but, surprisingly, there are few methods available for their control. Highly effective trapping may provide a means of controlling toads, either alone or as part of an integrated pest-management scheme. Existing cane toad trap designs use lights to lure insects to traps, and toads enter the traps to feed. Using a large, outdoor experimental arena and playback of cane toad mating calls, we examined the possibility that cane toads, like many other anurans, are attracted to conspecific mating vocalisations. We found that both male and female toads were attracted to quiet (47dB(A) at 1 m) playbacks, whereas only males responded to loud (67dB(A) at 1 m) playbacks with phonotaxis. We also tested whether playbacks broadcast from traps would be useful attractants to traps in the field. We captured three times more toads in traps with playbacks than in traps without playbacks, suggesting that playbacks can be used to enhance trapping success for toads.
Movement patterns and habitat use of rainforest stream frogs in northern Queensland, Australia: implications for extinction vulnerability
Authors: Rowley Jodi J. L. , Alford Ross A.
Published: September 2007

Amphibians are one of the most highly threatened groups of animals, but their effective conservation is hampered by a paucity of basic ecological knowledge, particularly for tropical stream-breeding species, in which declines have been most common and severe. We examined the movement patterns and habitat use of three stream-breeding frog species at five sites in northern Queensland, Australia. Movement and habitat use differed significantly among species. Litoria lesueuri moved more frequently and greater distances than did our other study species, and was often located away from streams, moving between intact rainforest and highly disturbed environments. Litoria genimaculata moved less frequently and shorter distances and was more restricted to stream environments compared with L. lesueuri, but was often located in the canopy. L. genimaculata occasionally moved large distances along and between streams, but was never located outside of intact rainforest. Litoria nannotis moved almost as frequently as the other species, but remained in streams during the day, did not move large distances along or between streams, and was always located within intact rainforest. Because of its sedentary behaviour, narrow habitat tolerance and affinity for stream environments, L. nannotis may be more vulnerable to extinction in human-modified landscapes compared with L. lesueuri and L. genimaculata.
Dissociable roles of the posterior parietal and the prefrontal cortex in manipulation and monitoring processes
Authors: Champod Anne Sophie , Petrides Michael
Published: September 2007

Numerous functional neuroimaging studies reported increased activity in the middorsolateral prefrontal cortex (MDLFC) and the posterior parietal cortex (PPC) during the performance of working memory tasks. However, the role of the PPC in working memory is not understood and, although there is strong evidence that the MDLFC is involved in the monitoring of information in working memory, it is also often stated that it is involved in the manipulation of such information. This event-related functional magnetic resonance imaging study compared brain activity during the performance of working memory trials in which either monitoring or manipulation of information was required. The results show that the PPC is centrally involved in manipulation processes, whereas activation of the MDLFC is related to the monitoring of the information that is being manipulated. This study provides dissociation of activation in these two regions and, thus, succeeds in further specifying their relative contribution to working memory.
Magnetic microposts as an approach to apply forces to living cells
Authors: Sniadecki Nathan J. , Anguelouch Alexandre , Yang Michael T. , Lamb Corinne M. , Liu Zhijun , Kirschner Stuart B. , Liu Yaohua , Reich Daniel H. , Chen Christopher S.
Published: September 2007

Cells respond to mechanical forces whether applied externally or generated internally via the cytoskeleton. To study the cellular response to forces separately, we applied external forces to cells via microfabricated magnetic posts containing cobalt nanowires interspersed among an array of elastomeric posts, which acted as independent sensors to cellular traction forces. A magnetic field induced torque in the nanowires, which deflected the magnetic posts and imparted force to individual adhesions of cells attached to the array. Using this system, we examined the cellular reaction to applied forces and found that applying a step force led to an increase in local focal adhesion size at the site of application but not at nearby nonmagnetic posts. Focal adhesion recruitment was enhanced further when cells were subjected to multiple force actuations within the same time interval. Recording the traction forces in response to such force stimulation revealed two responses: a sudden loss in contractility that occurred within the first minute of stimulation or a gradual decay in contractility over several minutes. For both types of responses, the subcellular distribution of loss in traction forces was not confined to locations near the actuated micropost, nor uniformly across the whole cell, but instead occurred at discrete locations along the cell periphery. Together, these data reveal an important dynamic biological relationship between external and internal forces and demonstrate the utility of this microfabricated system to explore this interaction.
Temperature-dependent heme kinetics with nonexponential binding and barrier relaxation in the absence of protein conformational substates
Authors: Ye Xiong , Ionascu Dan , Gruia Florin , Yu Anchi , Benabbas Abdelkrim , Champion Paul M.
Published: September 2007

We present temperature-dependent kinetic measurements of ultrafast diatomic ligand binding to the “bare” protoheme (L
1
-FePPIX-L
2
, where L
1
= H
2
O or 2-methyl imidazole and L
2
= CO or NO). We found that the binding of CO is temperature-dependent and nonexponential over many decades in time, whereas the binding of NO is exponential and temperature-independent. The nonexponential nature of CO binding to protoheme, as well as its relaxation above the solvent glass transition, mimics the kinetics of CO binding to myoglobin (Mb) but on faster time scales. This demonstrates that the nonexponential kinetic response observed for Mb is not necessarily due to the presence of protein conformational substates but rather is an inherent property of the solvated heme. The nonexponential kinetic data were analyzed by using a linear coupling model with a distribution of enthalpic barriers that fluctuate on slower time scales than the heme–CO recombination time. Below the solvent glass transition (
T
g
≈ 180 K), the average enthalpic rebinding barrier for H
2
O-PPIX-CO was found to be ≈1 kJ/mol. Above
T
g
, the barrier relaxes and is ≈6 kJ/mol at 290 K. Values for the first two moments of the heme doming coordinate distribution extracted from the kinetic data suggest significant anharmonicity above
T
g
. In contrast to Mb, the protoheme shows no indication of the presence of “distal” enthalpic barriers. Moreover, the wide range of Arrhenius prefactors (10
9
to 10
11
s
−1
) observed for CO binding to heme under differing conditions suggests that entropic barriers may be an important source of control in this class of biochemical reactions.
Renal expression of parvalbumin is critical for NaCl handling and response to diuretics
Authors: Belge Hendrica , Gailly Philippe , Schwaller Beat , Loffing Johannes , Debaix Huguette , Riveira-Munoz Eva , Beauwens Renaud , Devogelaer Jean-Pierre , Hoenderop Joost G. , Bindels René J. , Devuyst Olivier
Published: September 2007

The distal convoluted tubule (DCT) plays an essential role in the reabsorption of NaCl by the kidney, a process that can be inhibited by thiazide diuretics. Parvalbumin (PV), a Ca
2+
-binding protein that plays a role in muscle fibers and neurons, is selectively expressed in the DCT, where its role remains unknown. We therefore investigated the renal phenotype of PV knockout mice (
Pvalb
−/−
) vs. wild-type (
Pvalb
+/+
) littermates. PV colocalized with the thiazide-sensitive Na
+
-Cl
−
cotransporter (NCC) in the early DCT. The
Pvalb
−/−
mice showed increased diuresis and kaliuresis at baseline with higher aldosterone levels and lower lithium clearance. Acute furosemide administration increased diuresis and natriuresis/kaliuresis, but, surprisingly, did not increase calciuria in
Pvalb
−/−
mice. NaCl supplementation of
Pvalb
−/−
mice increased calciuria at baseline and after furosemide. The
Pvalb
−/−
mice showed no significant diuretic response to hydrochlorothiazide, but an accentuated hypocalciuria. A decreased expression of NCC was detected in the early DCT of
Pvalb
−/−
kidneys in the absence of ultrastructural and apoptotic changes. The PV-deficient mice had a positive Ca
2+
balance and increased bone mineral density. Studies in mouse DCT cells showed that endogenous NCC expression is Ca
2+
-dependent and can be modulated by the levels of PV expression. These results suggest that PV regulates the expression of NCC by modulating intracellular Ca
2+
signaling in response to ATP in DCT cells. They also provide insights into the Ca
2+
-sparing action of thiazides and the pathophysiology of distal tubulopathies.
Immunochemical recognition of A2E, a pigment in the lipofuscin of retinal pigment epithelial cells
Authors: Abeywickrama Chandima , Matsuda Hiroko , Jockusch Steffen , Zhou Jilin , Jang Young P. , Chen Bi-Xing , Itagaki Yasuhiro , Erlanger Bernard F. , Nakanishi Koji , Turro Nicholas J. , Sparrow Janet R.
Published: September 2007

The autofluorescent lipofuscin pigment A2E accumulates in retinal pigment epithelial cells with age and is particularly abundant in some retinal disorders. To generate a polyclonal antibody that recognizes this pyridinium bisretinoid molecule, we immunized rabbits with bovine serum albumin (BSA) conjugates in which the protein was linked to the A2E molecule via its pyridinium ethanolamine moiety. Analysis by matrix-assisted laser desorption ionization/time of flight mass spectrometry (MALDI-TOF MS) of the A2E–BSA conjugate indicated the presence of five intact A2E molecules covalently linked to BSA, thus deeming it a suitable antigen for immunization. By immunocytochemical staining, the rabbit polyclonal antibody recognized A2E that had accumulated in cultured cells, whereas dot-blot analysis revealed binding to both A2E and A2E-rabbit serum albumin (A2E–RSA) conjugate but no cross-reactivity with various retinoids. Preimmune serum was nonreactive. In fluorescence spectroscopy studies, antibody-A2E binding was evidenced by a fluorescence increase and by a blue-shift in the emission maximum consistent with a change in A2E milieu upon antibody binding. The changes in fluorescence emission upon antibody binding could reflect several processes including restrictions on trans-cis isomerization and intersystem crossing of photo-excited A2E.
The Face of Justice
Authors: Morris Ruth
Published: September 2007

Historically, although overall attitudes to court interpreting vary over time, certain issues are perennial : in particular, an individual's right (or otherwise) to interpretation (entitlement), deciding whether a need for interpretation exists (determination), and interpreter competence (quality). This paper strives to convey an awareness of the various difficulties that seem from case reports to have existed historically — and may indeed still be present in various judicial systems — in addressing these issues in a way which seems satisfactory to the various participants involved. It does so by quoting extensively the words of some of the judicial actors who over the decades have addressed this vital, but often woefully under-considered issue. The lamentable plight in which some language-handicapped defendants have found themselves may be guessed at from appellate courts' comments about the behaviour of lower courts.
On the theoretical implications of Cypriot Greek initial geminates
Authors: Muller Jennifer S.
Published: September 2007

Cypriot Greek contrasts singleton and geminate consonants in word-initial position. These segments are of particular interest to phonologists since two divergent representational frameworks, moraic theory (Hayes 1989) and timing-based frameworks, including CV or X-slot theory (Clements and Keyser 1983, Levin 1985), account for the behavior of initial geminates in substantially different ways. The investigation of geminates in Cypriot Greek allows these differences to be explored. As will be demonstrated in a formal analysis of the facts, the patterning of geminates in Cypriot is best accounted for by assuming that the segments are dominated by abstract timing units such as X- or C-slots, rather than by a unit of prosodic weight such as the mora.
Déplacement et repositionnement de la préposition à en français
Authors: Goyens Michèle , Lamiroy Béatrice , Melis Ludo
Published: September 2007

In Modern French, the preposition à has a large number of uses, in contrast to the Latin prepositions ad, ab and apud from which it derives. They can be classified into seven groups: complements expressing (1) place (where?), (2) time (when?), (3) manner, cause or instrument (how?); non locative complements commutating with (5) y or (6) lui, and finally (7) complements expressing possession. This evolution has been described lately as a result of a grammaticalization process, whereby the non locative uses emerged from the locative meaning by an increasing degree of abstraction.

First, we show how a comparison with synchronic Romance data (Italian and Spanish), and with diachronic data from Old French, allows us to refine the description of the overall grammaticalization process which involves French à. Moreover, we analyze less well known empirical data concerning lexical and morphosyntactic restrictions on present-day uses of French à. Both kinds of data account for our hypothesis : we argue in particular that the preposition’s main function is no longer that of expressing locative meaning (or adverbial meaning in general) but its use as a mere syntactic complementizer.

Furthermore, we show that the preposition is subject not only to a grammaticalization process, but also to a lexicalization process. That the latter also mainly holds for the adverbial uses of à provides evidence for the same hypothesis, viz. the core uses of Modern French à can be described as the result of a ‘repositioning’ of the preposition from the adverbial domain into the structural domain of the indirect object.
La légèreté en français comme déficience de mobilité
Authors: Abeillé Anne , Godard Danièle
Published: September 2007

We propose a new type of syntactic deficiency that we call “lightness”, which is relevant for all major syntactic categories. It applies to both words and phrases. Lightness is taken into account by different aspects of syntax (word order, extraction, adjunction sites, subcategorisation). Light forms differ from both incorporated and traditional “weak” forms, in the sense that they can be modified or coordinated. We show that lightness is relevant for French word order in the verbal domain. Light forms must be closer to the head (the verb) than other forms.
Contraintes d’ordre dans les groupes nominaux prédicatifs
Authors: Royauté Jean , Sabatier Paul
Published: September 2007

In this paper we try to explicit the specific and non specific constraints that govern the order of the constituents in French predicative noun phrases and compare them with those that govern the constituents of associated verbal clauses.
A relevance-theoretic account of the way we use and understand the English temporal adverb again and its Norwegian counterpart igjen
Authors: Fretheim Thorstein
Published: September 2007

The English temporal adverb again and the corresponding adverb igjen in Norwegian are words which do not encode a concept but rather an instruction to the audience to let the inferential phase of their comprehension process be guided by a specific contextual assumption. These adverbs have a procedural semantics in the sense of Relevance Theory, which distinguishes them semantically from an expression like once more or the prefix re-, both of which encode a conceptual meaning. English has a single lexical entry again whose encoded meaning is temporal yet not truth-conditional, and there is an exact correspondent igjen in the Norwegian lexicon, though Norwegian igjen in addition appears as two distinct non-temporal words encoding a concept and as a verbal particle forming a lexical entry together with a preceding verb. The full use range of the form igjen is found to be very similar to that of the Latin(ate) prefix re- as well as to the complex meaning of the verbal prefix ga- in the Niger-Congo language Ewe.
Narrative research and the challenge of accumulating knowledge
Authors: Josselson Ruthellen
Published: September 2007

Narrative research has produced an array of richly-detailed expositions of life as lived, well-interpreted studies full of nuance and insight that befit the complexity of human lives. This paper inquires into the necessity and possibilities of amalgamation of knowledge obtained through narrative research. As narrative studies, with their accompanying interpretations, accumulate, how do we “add them up?” What would a meta-analysis of narrative studies look like? The challenge that confronts us is how assimilate narrative understanding at a conceptual level in a way that does not return to a modernist frame, treating the various research reports as “facts” — but rather to treat them as situated interpretations. Conversation is offered as a metaphor and context within which knowledge is to be understood.
Story formulations in talk-in-interaction
Authors: Stokoe Elizabeth , Edwards Derek
Published: September 2007

This article contrasts ‘mainstream’ narrative analysis, and the study of researcher-elicited narrative accounts, with conversation analysis and the study of naturally occurring narratives-in-interaction. Our analysis extends previous conversation analytic and discursive psychological work on storytelling (i.e., how stories get embedded in sequences of talk; the actions storytelling does), by focusing on the location and function of speakers’ story formulations and orientations to narrative (e.g. “I think we should start at the beginning”, “You want the full story, or…?”, “there’s always two sides to every story”). Rather than treating such ‘meta-formulations’ as partial expressions of a general folk theory of narrative, we examine their action-orientation and the way they are shaped for the occasions of their production; how members’ commonsense notions of stories are displayed in the interactional contexts in which they are put to use. The argument is illustrated by a range of brief examples from mundane conversation, police interrogation, and neighbour dispute mediation.
The narrative negotiation of identity and belonging
Authors: Kraus Wolfgang
Published: September 2007

The present article discusses the need for a narrative approach within current identity theory and insists on the importance of an appropriate selection when it comes to a specific approach. It is argued that the most adequate theoretical relationship can be established to a poststructuralist and deconstructivist narratology. This understanding leads to a focus on narrativity and to the performative construction of identity. The question of belonging facilitates further elaboration on the various aspects of identity. Again, narrativity is proposed as a theoretical and methodological approach for analysis. Here situational self-positioning and positioning by others are seen as central in the negotiation of belonging. Particular emphasis is placed on small narratives and on positioning within the discursive situation.
Applied ethnopoetics
Authors: Blommaert Jan
Published: September 2007

Ethnopoetics is a form of narrative analysis designed, initially, for the analysis of folk stories and based on an ethnographic performance-based understanding of narrative emphasizing that meaning is an effect of performance. It offers opportunities for analyzing ‘voice’. The ways in which speakers themselves organize stories along indexical patterns of emphasis, focus, super- and subordination and so on. As such, it is a potentially very useful tool for tracking ‘local’ patterns of meaning-making in narrative. I argue that ethnopoetics could be productively applied to data in which different systems of meaning-making meet — a condition that defines many important service-providing systems in globalizing contexts. Asylum applications in Western Europe are a case in point, and examples will be used from that domain, but the potential usefulness of such an applied ethnopoetics stretches into many other types of service encounters in which crosscultural storytelling is crucial.
Narrative thinking and the emergence of postpsychological therapies
Authors: McLeod John
Published: September 2007

The growing emergence of an appreciation of the significance of narrative, within philosophy, the social sciences and the humanities, has had a significant impact on theory and practice within the field of counseling and psychotherapy. The influence of narrative thinking has been felt in two main ways. First, concepts of narrative have been assimilated into established forms of practice. For example, within psychoanalysis and psychodynamic therapy, it is now accepted that attention to narrative structures within the discourse of therapy can be used to generate a fuller understanding of the operation of well-known phenomena such as transference. The primary intention of this area of work has been to utilise narrative concepts to permit a deeper understanding of existing ideas about therapeutic processes and procedures. Second, a quite separate set of developments has seen the construction of an approach to therapy which begins from an acknowledgement of the central role of narrative and storytelling in lives and relationships. This alternative approach, generally described as “narrative therapy”, can be characterised as the formation of a postpsychological approach to therapy, which focuses on issues surrounding the performance of narratives within relationships, community and culture, rather than on inner psychological processes within individuals. It is argued that postpsychological narrative therapies have the potential to address key contemporary personal and social dilemmas in ways that are not possible within individualist models of therapy.
Role of intensively managed forests in future timber supply.
Authors: Cown D. J.
Published: September 2007

Much is reported about the destruction of natural forests and the consequences for global warming, while on the other hand, exotic plantations in some regions struggle to gain public acceptance. The earth's population is projected to rise to around 9 billion by 2050, with a concomitant increase in demand for forest products. Inevitably, forests in general, and managed forest in particular, will be called on to provide an ever-increasing proportion of local supplies and the international wood trade. Five countries - China, USA, Russian Federation, India and Japan - have each established more than 10 million ha of plantation forests, collectively accounting for 65% of the global plantation resource. Forest managers have made huge strides over the past 200 years or so in improving crops through the application of silviculture and genetics. Yields and quality have been greatly increased in managed forests and exotic plantations by spacing and pruning regimes that allow shorter rotations and improved quality. A common issue is now the higher proportion of juvenile wood produced in these situations, but technologies such as material segregation and recombination are reducing the impact on customers. A major emerging factor is the growing awareness of the significant contribution of forests to global warming by decision-makers, and pressure of commitments to international agreements, such as the Kyoto Protocol. This could lead to governments around the world creating and introducing a more favourable business climate for forestry activities, and a very significant increase in the proportion of global wood products derived from managed forests. However, the wood products industries cannot be complacent, as each generation brings new breeds of end users with less sentimental attachment with wood.
Bovine colostrum nutrient composition.
Authors: Kehoe S. I. , Heinrichs A. J.
Published: September 2007

The physiology of the ruminant placenta inhibits the transfer of large-molecular-weight structures
in utero
, thus making it essential that newborn calves receive a substantial amount of colostrum. Ruminant neonates must ingest colostrum for many reasons; however, attaining passive transfer of immunity from the dam is essential. Colostrum also contains other components that are important in satisfying nutritional requirements; high levels of fat, protein, vitamins, and minerals enable neonatal calves to begin building muscle, storing fat and initiating metabolic activities. Colostrum also provides high levels of growth factors and nucleotides, which have been reported to improve the maturation of intestinal tissue in growing neonates. Although average colostrum provides higher concentrations of nutrients compared with mature milk, there are differences among breeds of cows as well as parities that result in differing colostrum quality. For example, Holsteins produce colostrum that contains lower immunoglobulin concentrations when compared with other breeds. Also, younger parities produce colostrum with lower immunoglobulin concentrations compared with older cattle. Researchers have attempted to manipulate colostrum components through nutrition but have thus far only been successful in increasing certain vitamin and mineral concentrations. Continued research needs to evaluate whether other nutritional components of colostrum can be increased to improve neonatal survivability.
Animal health economics  where have we come from and where do we go next?
Authors: Rushton J. , Viscarra R. , Otte J. , McLeod A. , Taylor N.
Published: September 2007

The early initiatives on animal disease control measures were stimulated and justified by unacceptable losses of animals from rinderpest and foot and mouth disease (FMD) in Europe in the nineteenth century. In the 1960s, an increasingly large and ambitious veterinary profession turned to cost-benefit analysis methods in order to justify previous and proposed animal disease campaigns that supported livestock producers using more intensive production systems. These economic assessment methods were in the process of being developed and refined, and were increasingly important in the assessment of public investments. Some economists saw the use of cost-benefit analysis as simply an add-on to the technical aspects of animal disease control, and requested more rigorous economics when looking at the subject of animal health. This was the beginning of an ongoing debate on animal health economics that has developed into a number of different strands of thought. The paper reviews the development of animal health economics and the question whether there are new issues and opportunities that the subject needs to address. In this way it provides information on where animal health economics has come from and where it should be going next.