bluuebunny/crossref_metadata_2025 huggingface dataset:
Full‐wave modeling of the time domain reflectometry signal in wetted sandy soils using a random microstructure discretization: Comparison with experiments
Authors: Rejiba F. , Sagnard F. , Schamper C.
Published: July 2011

Time domain reflectometry (TDR) is a proven, nondestructive method for the measurement of the permittivity and electrical conductivity of soils, using electromagnetic (EM) waves. Standard interpretation of TDR data leads to the estimation of the soil's equivalent electromagnetic properties since the wavelengths associated with the source signal are considerably greater than the microstructure of the soil. The aforementioned approximation tends to hide an important issue: the influence of the microstructure and phase configuration in the generation of a polarized electric field, which is complicated because of the presence of numerous length scales. In this paper, the influence of the microstructural distribution of each phase on the TDR signal has been studied. We propose a two‐step EM modeling technique at a microscale range (): first, we define an equivalent grain including a thin shell of free water, and second, we solve Maxwell's equations over the discretized, statistically distributed triphasic porous medium. Modeling of the TDR probe with the soil sample was performed using a three‐dimensional finite difference time domain scheme. The effectiveness of this hybrid homogenization approach is tested on unsaturated Nemours sand with narrow granulometric fractions. The comparisons made between numerical and experimental results are promising, despite significant assumptions concerning (1) the TDR probe head and the coaxial cable and (2) the assumed effective medium theory homogenization associated with the electromagnetic processes arising locally between the liquid and solid phases at the grain scale.
The Cévennes‐Vivarais Mediterranean Hydrometeorological Observatory database
Authors: Boudevillain Brice , Delrieu Guy , Galabertier Bruno , Bonnifait Laurent , Bouilloud Ludovic , Kirstetter Pierre‐Emmanuel , Mosini Marie‐Laure
Published: July 2011

Intense rain events frequently result in devastating flash floods in Mediterranean regions. To improve the understanding and prediction of these phenomena, the Cévennes‐Vivarais Mediterranean Hydrometeorological Observatory (CVMHO) was set up in 2000. The observation strategies deployed include the detailed and long‐lasting (>10 years) observation in the Cévennes‐Vivarais region (France) using both operational observation systems and research instrumentation. The present note describes the procedures implemented by CVMHO to critically analyze and generate hydrometeorological products for research. The related data can be viewed or downloaded via the Système d'Extraction et de Visualisation des Données de l'Observatoire en Ligne (SEVnOL) interface on the CVMHO Web site.
Nonlocal thermal-elasticity for nanobeam deformation: Exact solutions with stiffness enhancement effects
Authors: Lim C. W. , Yang Q.
Published: July 2011

The nanomechanical response for a nanobeam under thermal effects is investigated by using the nonlocal elasticity field theory, which was first proposed by Eringen in the early 1970s. The nonlocal constitutive relation is adopted to determine the strain energy density which considers the history of nonlinear straining with respect to an unstrained state. Based on the variational principle and integrating the straining energy density over the entire domain of interest influenced by a temperature field, a new higher-order differential equation and the corresponding higher-order boundary conditions are derived. The thermal-elastic effects of typical nanobeams are presented where new exact analytical solutions with physical boundary conditions are derived. Subsequently, the effects of the nonlocal nanoscale and temperature on the nanobeam transverse deflection are analyzed and discussed. It is observed that these factors have a significant influence on the transverse deflection. In particular, the nanobeam stiffness is greatly enhanced, or the transverse deflection is significantly reduced, with an increasing nonlocal stress effect. A conclusion is drawn that at low and room temperature the nanobeam transverse deflection decreases with an increasing temperature difference, while at high temperature the transverse deflection increases as the temperature difference increases.
Ion acoustic shock waves in degenerate plasmas
Authors: Akhtar N. , Hussain S.
Published: July 2011

Korteweg de Vries Burgers equation for negative ion degenerate dissipative plasma has been derived using reductive perturbation technique. The quantum hydrodynamic model is used to study the quantum ion acoustic shock waves. The effects of different parameters on quantum ion acoustic shock waves are studied. It is found that quantum parameter, electrons Fermi temperature, temperature of positive and negative ions, mass ratio of positive to negative ions, viscosity, and density ratio have significant impact on the shock wave structure in negative ion degenerate plasma.
Terahertz spectroscopy of dynamics of coupling between the coherent longitudinal optical phonon and plasmon in the surge current of instantaneously photogenerated carriers flowing through the i-GaAs layer of an i-GaAs/n-GaAs epitaxial structure
Authors: Takeuchi Hideo , Tsuruta Syuichi , Nakayama Masaaki
Published: July 2011

We demonstrate the dynamics of coupling between the coherent longitudinal optical (LO) phonon and plasmon of instantaneously photogenerated electrons in an undoped GaAs/n-type GaAs (i-GaAs/n-GaAs) epitaxial structure using time-domain terahertz spectroscopy. Initially, we experimentally and numerically clarify the presence of the built-in electric field in the i-GaAs layer of the i-GaAs/n-GaAs epitaxial layer. Next, we performed the terahertz-wave measurements of the i-GaAs/n-GaAs epitaxial structure at various excitation conditions from a low density excitation regime to a high excitation regime. The LO-phonon-plasmon coupled (LOPC) mode has been confirmed from the terahertz-wave measurement. It is found that the frequency of the LOPC mode is determined by the pump-beam power. This fact demonstrates that the LOPC mode is formed in the i-GaAs layer. In addition, we performed the time-partitioning Fourier transform in order to reveal the dynamical change in the LOPC mode as a function of time delay. Using this analysis, we have observed that the disappearance of the LOPC mode immediately occurs within the time delay of 0.6 ps. Following the disappearance of the LOPC mode, only the bare coherent GaAs LO phonon dominates the terahertz waves.
Carbon nanotube seeded silicon crystal growth
Authors: Li Y. F. , Li H. , Sun F. W. , Zhang X. Q. , Liew K. M.
Published: July 2011

Crystal growth of liquid silicon on the heterogeneous surfaces of carbon nanotubes (CNTs) is simulated. Silicon atoms are concentrated to form perfect coaxial cylindrical configurations around CNT cores. The heredity effect makes silicon imprint cylindrical shapes of CNTs during the solidification. The CNTs have a great influence on the stacking sequence of silicon atoms. Growth competition between CNT cores is clearly observed, which results in defects at the shared interface. The internal potential field around CNTs is responsible for growth competition and the heredity effect.
Polarization justified Fukui functions: The theory and applications for molecules
Authors: Komorowski Ludwik , Lipiński Józef , Szarek Paweł , Ordon Piotr
Published: July 2011

The Fukui functions based on the computable local polarizability vector have been presented for a group of simple molecules. The necessary approximation for the density functional theory softness kernel has been supported by a theoretical analysis unifying and generalizing early concepts produced by the several authors. The exact relation between local polarizability vector and the derivative of the nonlocal part of the electronic potential over the electric field has been demonstrated. The resulting Fukui functions are unique and represent a reasonable refinement when compared to the classical ones that are calculated as the finite difference of the density in molecular ions. The new Fukui functions are strongly validated by their direct link to electron dipole polarizabilities that are reported experimentally and by other computational methods.
On solutions to the “Faddeev-Niemi” equations
Authors: Niemi Antti J. , Wereszczyński Andrzej
Published: July 2011

Recently it has been pointed out that the so-called Faddeev-Niemi equations that describe the Yang-Mills equations of motion in terms of a decomposed gauge field, can have solutions that obey the standard Yang-Mills equations with a source term. Here we argue that the source term is covariantly constant. Furthermore, we find that there are solutions of the Yang-Mills equation with a covariantly constant source term that are not solutions to the Faddeev-Niemi equations. We also present a general class of gauge field configurations that obey the Faddeev-Niemi equation but do not solve the Yang-Mills equation. We propose that these configurations might have physical relevance in a strongly coupled phase, where spin-charge separation takes place and the Yang-Mills theory cannot be described in terms of a Landau liquid of asymptotically free gluons.
The products of the thermal decomposition of CH3CHO
Authors: Vasiliou AnGayle , Piech Krzysztof M. , Zhang Xu , Nimlos Mark R. , Ahmed Musahid , Golan Amir , Kostko Oleg , Osborn David L. , Daily John W. , Stanton John F. , Barney Ellison G.
Published: July 2011

We have used a heated 2 cm × 1 mm SiC microtubular (μtubular) reactor to decompose acetaldehyde: CH3CHO + Δ → products. Thermal decomposition is followed at pressures of 75–150 Torr and at temperatures up to 1675 K, conditions that correspond to residence times of roughly 50–100 μs in the μtubular reactor. The acetaldehyde decomposition products are identified by two independent techniques: vacuum ultraviolet photoionization mass spectroscopy (PIMS) and infrared (IR) absorption spectroscopy after isolation in a cryogenic matrix. Besides CH3CHO, we have studied three isotopologues, CH3CDO, CD3CHO, and CD3CDO. We have identified the thermal decomposition products CH3 (PIMS), CO (IR, PIMS), H (PIMS), H2 (PIMS), CH2CO (IR, PIMS), CH2=CHOH (IR, PIMS), H2O (IR, PIMS), and HC≡CH (IR, PIMS). Plausible evidence has been found to support the idea that there are at least three different thermal decomposition pathways for CH3CHO; namely, radical decomposition: CH3CHO + Δ → CH3 + [HCO] → CH3 + H + CO; elimination: CH3CHO + Δ → H2 + CH2=C=O; isomerization/elimination: CH3CHO + Δ → [CH2=CH–OH] → HC≡CH + H2O. An interesting result is that both PIMS and IR spectroscopy show compelling evidence for the participation of vinylidene, CH2=C:, as an intermediate in the decomposition of vinyl alcohol: CH2=CH–OH + Δ → [CH2=C:] + H2O → HC≡CH + H2O.
Strong red emission in Pr doped (Bi0.5Na0.5)TiO3 ferroelectric ceramics
Authors: Sun Haiqin , Peng Dengfeng , Wang Xusheng , Tang Mianmian , Zhang Qiwei , Yao Xi
Published: July 2011

The photoluminescence of Pr doped (Bi0.5Na0.5)TiO3 ferroelectric ceramics prepared by conventional solid-state reaction were investigated. A bright red emission is observed at room temperature, which ascribed to 1D2→3H4 transition. The excitation bands are mainly located at 440 ∼ 505 nm, which is adaptable to the emission band of commercial blue light-emitting diodes (LEDs) chips. The optimal emission intensity was also obtained when Pr doping level was 0.003 mol. Meanwhile, the enhanced ferroelectric properties were obtained by Pr doping. The results show that Pr doped (Bi0.5Na0.5)TiO3 ceramics as a multifunctional material may be useful for white LEDs, sensor, and optical-electro integration.
Very low effective Schottky barrier height for erbium disilicide contacts on n-Si through arsenic segregation
Authors: Reckinger Nicolas , Poleunis Claude , Dubois Emmanuel , Augustin Duţu Constantin , Tang Xiaohui , Delcorte Arnaud , Raskin Jean-Pierre
Published: July 2011

The segregation of As+ ions implanted into thin Er films deposited on n-Si substrates is studied after ErSi2−x formation. The same lowering of the effective Schottky barrier height (SBH) below 0.12 eV is obtained at moderate annealing temperatures, regardless of the redistribution of As dopants at the ErSi2–x/Si interface. On the other hand, if the implanted dose is slightly enhanced, the annealing temperature required to reach sub-0.12-eV effective SBH can be further reduced. This process enables the formation of very low effective SBH ErSi2–x/n-Si contacts with a low thermal budget.
Two-dimensional electron gas properties by current-voltage analyses of Al0.86In0.14N/AlN/GaN heterostructures
Authors: Pandey S. , Fraboni B. , Cavalcoli D. , Minj A. , Cavallini A.
Published: July 2011

We report on the current transport properties of AlInN/AlN/GaN high electron mobility transitors with different AlN interlayer thickness. We determined the two-dimensional electron gas (2DEG) properties directly from simple current-voltage measurements, carried out with two Schottky contacts in a planar back-to-back configuration. A model has been developed to straightforwardly extract the 2DEG electrical properties from room-temperature current-voltage curves, and we correlated them to the effects of varying AlN thickness. The 2DEG properties calculated from current-voltage analyses are in very good agreement with results obtained with standard Hall measurements.
Modulation of strain, resistance, and capacitance of tantalum oxide film by converse piezoelectric effect
Authors: Jia Yanmin , Tian Xiangling , Si Jianxiao , Huang Shihua , Wu Zheng , Zhu Chenchen
Published: July 2011

We deposited tantalum oxide film on a laminate structure composed of a Si substrate and a piezoelectric 0.72Pb(Mg1/3Nb2/3)O3–0.28PbTiO3 single crystal and achieved in situ modulation of the resistance and capacitance of the Ta2O5 film. The modulation arises from the induced lattice strain in the Ta2O5 film, which is induced by the electric-field-induced strain in the piezoelectric crystal. Under an external electric field of ∼2 kV/cm, the longitudinal gauge factor of the Ta2O5 film is ∼3300. The control of the strain using the converse piezoelectric effect may be further extended to tune the intrinsic strain of other oxide thin films.
Energy gaps in nitrogen delta-doping graphene: A first-principles study
Authors: Wei Xiao-Lin , Fang Hui , Wang Ru-Zhi , Chen Yuan-Ping , Zhong Jian-Xin
Published: July 2011

First-principles calculations are performed to study the modulation of energy gaps in nitrogen delta-doping (N δ-doping) graphene and armchair-edge graphene nanoribbons (AGNRs). The energy gap of graphene only opens at a large nitrogen doping content. For AGNRs, the energy gaps tend to decrease with the N δ-doping, and an interesting transition from direct to indirect bandgap is observed. Moreover, the effects of N δ-doping on energy gaps incline to decease with the reduction of the doping content. Our results may help to design novel graphene-based nanoelectronics devices by controlling N δ-doping of graphene.
Ultrafast carrier dynamics in gold/iron-oxide nanocrystal heterodimers
Authors: Korobchevskaya Kseniya , George Chandramohan , Diaspro Alberto , Manna Liberato , Cingolani Roberto , Comin Alberto
Published: July 2011

Colloidal nanocrystal heterodimers composed of a gold domain and an iron oxide domain have been investigated by femtosecond transient absorption spectroscopy. The measured decay times were compared with the ones obtained from samples of “only” gold nanocrystals and iron oxide nanocrystals. Our results indicate that there is no significant charge transfer at the interface between gold and iron oxide in heterodimers.
High-pressure Raman scattering in wurtzite indium nitride
Authors: Ibáñez J. , Manjón F. J. , Segura A. , Oliva R. , Cuscó R. , Vilaplana R. , Yamaguchi T. , Nanishi Y. , Artús L.
Published: July 2011

We perform Raman-scattering measurements at high hydrostatic pressures on c-face and a-face InN layers to investigate the high-pressure behavior of the zone-center optical phonons of wurtzite InN. Linear pressure coefficients and mode Grüneisen parameters are obtained, and the experimental results are compared with theoretical values obtained from ab initio lattice-dynamical calculations. Good agreement is found between the experimental and calculated results.
Infinitely stiff composite via a rotation-stabilized negative-stiffness phase
Authors: Kochmann D. M. , Drugan W. J.
Published: July 2011

We show that an elastic composite material having a component with sufficiently negative stiffness to produce positive-infinite composite stiffness can be stabilized by the gyroscopic forces produced by composite rotation.
Klein tunnelling model of low energy electron field emission from single-layer graphene sheet
Authors: Sun S. , Ang L. K. , Shiffler D. , Luginsland J. W.
Published: July 2011

By considering the effect of Klein tunneling for low energy electrons with linear energy dispersion, a model has been constructed to calculate the amount of emitted line current density from a single-layer graphene sheet, which is vertically aligned inside a dc gap. It is found that the current-voltage scaling obtained from the constructed Klein tunneling model is very different from the traditional field emission model based on the Fowler-Nordheim (FN) law. Under the same geometrical field enhancement factor, our model predicts a much higher emitted current as compared to the FN law at low voltages.
Interatomic potential to calculate the driving force, optimized composition, and atomic structure of the Cu-Hf-Al metallic glasses
Authors: Cui Y. Y. , Li J. H. , Dai Y. , Liu B. X.
Published: July 2011

An interatomic potential is proposed for the Cu-Hf-Al system and applied in molecular dynamics/statics simulations. Simulations predict a hexagonal composition region for the Cu-Hf-Al metallic glass formation. Kinetically, a local maximum driving force, defined by energy difference between the solid solution and disordered state, is predicted to be at Cu48Hf41Al11, close to the experimentally measured optimized composition. Moreover, Voronoi tessellation analysis shows that though the icosahedron and icosidihedron are dominant configurations, the fractions of both icosihexahedron and icosioctahedron decrease with increasing Al content, correlating closely with the atomic radii and the heat of mixing of the component metals.
An early transient water deficit reduces flower number and pod production but increases seed size in chickpea (Cicer arietinum L.)
Authors: Fang X.-W. , Turner N. C. , Li F.-M. , Siddique K. H. M.
Published: July 2011

Terminal drought is known to decrease flower production, increase flower and pod abortion, and decrease yield of chickpea (Cicer arietinum L.), but the effects of early-season drought have not been evaluated. The influence of an early transient water deficit on flower and pod production and abortion, and seed yield and its components was evaluated in two chickpea cultivars, Rupali, a desi type, and Almaz, a kabuli type. Thirty-six-day-old plants were subjected to: (i) a transient water deficit by withholding water for 35 days, and then rewatered (WS), and (ii) kept well watered (WW) throughout. In the WS treatment the soil water content, leaf relative water content and leaf photosynthetic rate decreased after water was withheld and, following rewatering, recovered to the WW level. Despite the WS treatment being imposed at different phenological stages in the two cultivars, WS reduced flower number per plant by ~50% in Rupali and Almaz, respectively, compared with the WW plants. In WW plants, ~15% of flowers aborted in both cultivars, and 42 and 67% of the pods aborted in Rupali and Almaz, respectively, whereas in WS plants, 18 and 23% of flowers aborted and 27 and 67% of pods aborted in Rupali and Almaz, respectively. While seed growth in WS plants of Rupali and Almaz occurred primarily after the plants were rewatered, the duration of seed growth decreased by 17 and 36 days, the maximum rate of seed filling increased by 3 times and 5 times, and seed size increased by 26 and 16%, respectively, compared with the WW plants. Seed yield per plant in WS plants decreased by 31% in Rupali and 38% in Almaz compared with the WW controls. The early transient water deficit decreased flower production, but improved flower and pod development; increased the rate of seed growth and increased final seed size; and had a smaller effect on seed yield compared with chickpea subjected to terminal drought.
Relationship between nitrogen uptake and use efficiency of winter wheat grown in the North China Plain
Authors: Wang R. F. , An D. G. , Hu C. S. , Li L. H. , Zhang Y. M. , Jia Y. G. , Tong Y. P.
Published: July 2011

Wheat (Triticum aestivum L.) cultivars with improved nitrogen-use efficiency (NUE) under low and medium N conditions will help to minimise production costs and nitrate-N contamination. The study was conducted to determine the NUE diversities of winter wheat genotypes, and to evaluate the possible physiological mechanisms contributing to these differences. A set of 12 winter wheat genotypes, including S4185 as control genotype, were grown at high N (applied with 180 kg N/ha as urea) and low N (with no N fertiliser, N-deficient) plots in 2005–06 and 2007–08 growing seasons (i.e. four environments). ANOVA showed significant differences among genotypes for all traits measured. Among genotypes, XJ19-1 had significantly higher NUE and N uptake efficiency (NUpE) than S4185 at the two N levels in the 2 years (P < 0.05). KN9204 had significantly higher NUE in the four environments and higher NUpE in three out of four environments than S4185 (P < 0.05). WR9603 and XJ138-1 had higher NUE and NUpE than S4185 in two or three out of four environments (P < 0.05). XJ19-1, KN9204, WR9603 and XJ138-1 also showed higher grain yield (GY) and aboveground dry matter (DM) than S4185 in at least two environments (P < 0.05). KN9204 were 45.7 and 23.1% higher in root dry weight (RDW) of the top 40-cm soil profile compared with J411 at high N and low N plots, respectively (P < 0.05). In addition, there was a highly positive correlation between RDW and grain N yield (GNY) of KN9204 and J411 (P < 0.01). Closely positive correlation between NUE and GY, DM, GNY and NUpE at both N levels in the 2 years (P < 0.01), and between N utilisation efficiency (NUtE) and NUE only at high N plot (P < 0.05) were found. Our results indicated that NUpE was the important factor of NUE under low N conditions, and both NUpE and NUtE were the most important NUE components under high N conditions.
Vertical distribution profiles and temporal growth patterns of roots in selected oilseeds, pulses and spring wheat
Authors: Gan Yantai , Liu Liping , Cutforth Herb , Wang Xiaoyu , Ford Greg
Published: July 2011

Knowledge of rooting systems and their vertical distribution in the soil profile for field crops is required for designing crop rotation systems that allow for effective use of soil water and nutrients. This study determined the vertical distribution in the upper 100 cm of the soil profile and the temporal growth patterns of roots for three pulses (Cicer arietinum L. chickpea, Pisum sativum L. dry pea, and Lens culinaris Medik. lentil) and three oilseeds (napus canola, juncea mustard, and Linum usitatissimum flax) and spring wheat (Triticum aestivum L.). Crops were grown in 150-mm-diameter, 1-m-long lysimeters under low- (rainfall only) and high- (rainfall + irrigation) water availabilities in a 2-year (2006–07) field study, in Swift Current, Canada. Root volumes increased significantly from the seedling stage, reached the maximum at the late-flowering, and declined to maturity; this temporal growth pattern was independent with water availability. On average, ~44% of the root volume was in the top 20-cm soil layer, 70% in the top 40 cm, and 90% in the top 60 cm. About 5% of the roots in pulse crops were located below 60 cm in depth, significantly less than the 12% for wheat, 13% for mustard, and 18% for canola. Under low-water conditions, Brassica oilseeds had greater root volume (33 mm3 cm–3) than wheat (27 mm3 cm–3), but under high-water conditions, root volumes were 27 mm3 cm–3 for the Brassicas and 32 mm3 cm–3 for wheat. Pulses had greatest root volumes under both low- (40 mm3 cm–3) and high- (42 mm3 cm–3) water conditions, with largest root diameters among crops evaluated, whereas flax the smallest. Rotating the shallower but larger diameter, thicker-rooting pulses with deeper but smaller diameter, thinner-rooting oilseeds or wheat may increase water- and nutrient-use efficiency at the system level.
Survival of starving yeast is correlated with oxidative stress response and nonrespiratory mitochondrial function
Authors: Petti Allegra A. , Crutchfield Christopher A. , Rabinowitz Joshua D. , Botstein David
Published: July 2011

Survival of yeast during starvation has been shown to depend on the nature of the missing nutrient(s). In general, starvation for “natural” nutrients such as sources of carbon, phosphate, nitrogen, or sulfate results in low death rates, whereas starvation for amino acids or other metabolites in auxotrophic mutants results in rapid loss of viability. Here we characterized phenotype, gene expression, and metabolite abundance during starvation for methionine. Some methionine auxotrophs (those with blocks in the biosynthetic pathway) respond to methionine starvation like yeast starving for natural nutrients such as phosphate or sulfate: they undergo a uniform cell cycle arrest, conserve glucose, and survive. In contrast, methionine auxotrophs with defects in the transcription factors Met31p and Met32p respond poorly, like other auxotrophs. We combined physiological and gene expression data from a variety of nutrient starvations (in both respiratory competent and incompetent cells) to show that successful starvation response is correlated with expression of genes encoding oxidative stress response and nonrespiratory mitochondrial functions, but not respiration per se.
Mutation of the conserved polyadenosine RNA binding protein, ZC3H14/dNab2, impairs neural function in
Drosophila
and humans
Authors: Pak ChangHui , Garshasbi Masoud , Kahrizi Kimia , Gross Christina , Apponi Luciano H. , Noto John J. , Kelly Seth M. , Leung Sara W. , Tzschach Andreas , Behjati Farkhondeh , Abedini Seyedeh Sedigheh , Mohseni Marzieh , Jensen Lars R. , Hu Hao , Huang Brenda , Stahley Sara N. , Liu Guanglu , Williams Kathryn R. , Burdick Sharon , Feng Yue , Sanyal Subhabrata , Bassell Gary J. , Ropers Hans-Hilger , Najmabadi Hossein , Corbett Anita H. , Moberg Kenneth H. , Kuss Andreas W.
Published: July 2011

Here we report a human intellectual disability disease locus on chromosome 14q31.3 corresponding to mutation of the
ZC3H14
gene that encodes a conserved polyadenosine RNA binding protein. We identify
ZC3H14
mRNA transcripts in the human central nervous system, and we find that rodent ZC3H14 protein is expressed in hippocampal neurons and colocalizes with poly(A) RNA in neuronal cell bodies. A
Drosophila melanogaster
model of this disease created by mutation of the gene encoding the ZC3H14 ortholog dNab2, which also binds polyadenosine RNA, reveals that dNab2 is essential for development and required in neurons for normal locomotion and flight. Biochemical and genetic data indicate that dNab2 restricts bulk poly(A) tail length in vivo, suggesting that this function may underlie its role in development and disease. These studies reveal a conserved requirement for
ZC3H14/dNab2
in the metazoan nervous system and identify a poly(A) RNA binding protein associated with a human brain disorder.
Asymptotic expansions of certain partial theta functions
Authors: Berndt Bruce , Kim Byungchan
Published: July 2011

We establish an asymptotic expansion for a class of partial theta functions generalizing a result found in Ramanujan’s second notebook. Properties of the coefficients in this more general asymptotic expansion are studied, with connections made to combinatorics and a certain Dirichlet series.
Genetic analysis in the Collaborative Cross breeding population
Authors: Philip Vivek M. , Sokoloff Greta , Ackert-Bicknell Cheryl L. , Striz Martin , Branstetter Lisa , Beckmann Melissa A. , Spence Jason S. , Jackson Barbara L. , Galloway Leslie D. , Barker Paul , Wymore Ann M. , Hunsicker Patricia R. , Durtschi David C. , Shaw Ginger S. , Shinpock Sarah , Manly Kenneth F. , Miller Darla R. , Donohue Kevin D. , Culiat Cymbeline T. , Churchill Gary A. , Lariviere William R. , Palmer Abraham A. , O'Hara Bruce F. , Voy Brynn H. , Chesler Elissa J.
Published: July 2011

Genetic reference populations in model organisms are critical resources for systems genetic analysis of disease related phenotypes. The breeding history of these inbred panels may influence detectable allelic and phenotypic diversity. The existing panel of common inbred strains reflects historical selection biases, and existing recombinant inbred panels have low allelic diversity. All such populations may be subject to consequences of inbreeding depression. The Collaborative Cross (CC) is a mouse reference population with high allelic diversity that is being constructed using a randomized breeding design that systematically outcrosses eight founder strains, followed by inbreeding to obtain new recombinant inbred strains. Five of the eight founders are common laboratory strains, and three are wild-derived. Since its inception, the partially inbred CC has been characterized for physiological, morphological, and behavioral traits. The construction of this population provided a unique opportunity to observe phenotypic variation as new allelic combinations arose through intercrossing and inbreeding to create new stable genetic combinations. Processes including inbreeding depression and its impact on allelic and phenotypic diversity were assessed. Phenotypic variation in the CC breeding population exceeds that of existing mouse genetic reference populations due to both high founder genetic diversity and novel epistatic combinations. However, some focal evidence of allele purging was detected including a suggestive QTL for litter size in a location of changing allele frequency. Despite these inescapable pressures, high diversity and precision for genetic mapping remain. These results demonstrate the potential of the CC population once completed and highlight implications for development of related populations.
Complex traits analysis of chicken growth using targeted genetical genomics
Authors: Cabrera C. P. , Dunn I. C. , Fell M. , Wilson P. W. , Burt D. W. , Waddington D. , Talbot R. , Hocking P. M. , Law A. , Knott S. , Haley C. S. , de Koning D. J.
Published: July 2011

Dissecting the genetic control of complex trait variation remains very challenging, despite many advances in technology. The aim of this study was to use a major growth quantitative trait locus (QTL) in chickens mapped to chromosome 4 as a model for a targeted approach to dissect the QTL. We applied a variant of the genetical genomics approach to investigate genome‐wide gene expression differences between two contrasting genotypes of a marked QTL. This targeted approach allows the direct quantification of the link between the genotypes and the genetic responses, thus narrowing the QTL‐phenotype gap using fewer samples (i.e. microarrays) compared with the genome‐wide genetical genomics studies. Four differentially expressed genes were localized under the region of the QTL. One of these genes is a potential positional candidate gene (AADAT) that affects lysine and tryptophan metabolism and has alternative splicing variants between the two genotypes. In addition, the lysine and glycolysis metabolism pathways were significantly enriched for differentially expressed genes across the genome. The targeted approach provided a complementary route to fine mapping of QTL by characterizing the local and the global downstream effects of the QTL and thus generating further hypotheses about the action of that QTL.
Managing multiple myeloma: the emerging role of novel therapies and adapting combination treatment for higher risk settings
Authors: Richardson Paul G. , Laubach Jacob , Mitsiades Constantine S. , Schlossman Robert , Hideshima Teru , Redman Katherine , Chauhan Dharminder , Ghobrial Irene M. , Munshi Nikhil , Anderson Kenneth C.
Published: July 2011

Novel therapies have transformed the treatment paradigm for multiple myeloma with significant improvements in survival now seen in both younger and older patients. Nonetheless, the disease is heterogeneous and high‐risk patients in particular continue to have poor outcome. Moreover, the disease remains incurable. Efforts to refine risk stratification and disease characteristics continue with the use of cytogenetics, enhanced imaging techniques and other new technologies, such as genomics. The integration of novel therapies into induction therapy, consolidation and maintenance continues to evolve, and the appropriate use of combination strategies including proteasome inhibition and immunomodulatory treatment is emerging as a platform with application across the disease spectrum. Despite these advances, resistance to novel agents occurs and so the identification of new targets and the recognition of clonal heterogeneity are especially important as improvements to current treatment strategies are developed, with the goal of further improving patient outcome.
A follow‐up evaluation of the impact of the Chief Nursing Officer’s review of mental health nursing in Mental Health Trusts and Universities in England: comparisons of two e‐surveys
Authors: Baker John , Swarbrick Caroline , Campbell Malcolm , Playle John , Lovell Karina
Published: July 2011

baker j., swarbrick c., campbell m., playle j. & lovell k. (2012) A follow‐up evaluation of the impact of the Chief Nursing Officer’s review of mental health nursing in Mental Health Trusts and Universities in England: comparisons of two e‐surveys. Journal of Advanced Nursing68(3), 625–635.

Aims.  This article is a report of a study that aimed to establish a national picture of the implementation of Review recommendations over time in both Mental Health Trusts and Higher Education Institutions (Universities) in England.

Background.  The 2006 Review of Mental Health Nursing in England by the Chief Nursing Officer made 17 key recommendations for Mental Health Trusts and Universities to improve mental health nursing. This article outlines key findings from a national survey of National Health Service Trusts and Universities in England with regard to prioritization and progress on implementation of these recommendations.

Methods.  An e‐survey was carried out in 2008‐2009 based on the Chief Nursing Officer review recommendations and guidance. Participants included all Trusts which delivered mental health services (n = 68) and Universities which delivered pre‐registration mental health nursing education (n = 50) in England.

Results.  There appears to be some evidence that the Chief Nursing Officer review of Mental Health Nursing in England continues to be implemented in both Mental Health Trusts and Universities. There is variety in levels of implementation, but Mental Health Trusts and Universities broadly agree on priority areas.

Conclusions.  The Chief Nursing Officer review has been influential in focusing the care and education of mental health nurses and services in England. There appears to be a range of barriers and facilitators which aid the implementation of healthcare policy. More attention is required from researchers to enhance and evaluate the impact of policy implementation on the quality of care provided.
A qualitative analysis of the nutritional requirements of palliative care patients
Authors: Muir C. I. , Linklater G. T.
Published: July 2011

Background:  The National Health Servive (NHS) Quality Improvement Scotland developed nutritional Clinical Standards to address the problem of malnutrition in hospitals. NHS palliative care units are obliged to incorporate these standards into nutritional aspects of care. The nutritional needs of this patient population are under‐researched. The present study aimed to explore patients’ views of nutrition, to begin to understand their concerns and to determine whether such standards meet the needs of patients in the palliative care setting.

Methods:  A qualitative study was conducted in 2009 in an NHS Palliative Care Unit. Six inpatients were involved in one‐to‐one interviews, which were audiotaped and transcribed verbatim. The transcripts were subject to qualitative data analysis in accordance with a previous framework.

Results:  A recurring theme that emerged was that of change and uncertainty. Four main areas subject to change were: disease state, symptoms, oral dietary intake and weight. Each change could exert control over, or be controlled by, the patient. When patients were eventually unable to exert control, they accepted the change, either willingly or enforced, thereby unintentionally setting their own targets.

Conclusions:  The present study enables a deeper understanding of the concerns that palliative care patients have regarding their oral dietary intake and weight. Their ‘malnutrition’ not only refers to physical malnutrition alone, but also incorporates psychological and social ‘malnutrition’. When applying standards or protocols regarding nutritional care, these wider issues must be taken into account to meet patients’ nutritional needs.
The development of nonweighed pilot methods for estimating phenylalanine exchanges in non‐phenylketonuria volunteers
Authors: Gokmen‐Ozel H. , Daly A. , Davies P. , MacDonald A.
Published: July 2011

Background:  In children with phenylketonuria (PKU), the daily weighing of the phenylalanine allowance from food is advocated. There is a need to develop nonweighed methods of measuring dietary phenylalanine, aiming to ease caregiver burden and possibly improve dietary adherence. The accuracy of three methods (household measures, digital photographs and weighing) for measuring 50‐mg phenylalanine exchanges for PKU was investigated in a randomised, controlled trial.

Methods:  There were 51 volunteers (32 females; 19 males; median age: 34 years, range 13–77 years), who were all unconnected with PKU. For three consecutive days, all volunteers attended a research centre and, each day, were randomly allocated a different method (household measures, digital photographs and weighing) for phenylalanine exchange measurement. On each day, they measured the amount of food equivalent to one 50‐mg phenylalanine exchange for 24 common foods. All phenylalanine exchange samples (3672 samples) were then reweighed by the investigators.

Results:  No method of measuring 50‐mg phenylalanine exchanges was accurate when used by volunteers. The median percentages (range) of all food samples within 10% of target were only 67% (41–98), 44% (4–96) and 41% (4–98) for weighing, household measures and photographs, respectively. The respective median (range) of samples within 20% of the target weights were: 96% (51–100) weighing, 82% (10–100) photographs and 80% (6–100) household measures. No noteworthy difference in accuracy was observed between household measures and photographs.

Conclusions:  Volunteers not associated with PKU could not measure 50‐mg phenylalanine exchanges accurately using weighing, household measurements or photographs. Therefore, it is important to consider developing methods for improving accuracy of measurement of 50‐mg phenylalanine exchanges in PKU.
Preliminary pharmacokinetics and cardiovascular effects of fenoldopam continuous rate infusion in six healthy dogs
Authors: BLOOM C. A. , LABATO M. A. , HAZARIKA S. , COURT M. H.
Published: July 2011

Bloom, C. A., Labato, M. A., Hazarika, S., Court, M. H. Preliminary pharmacokinetics and cardiovascular effects of fenoldopam continuous rate infusion in six healthy dogs. J. vet. Pharmacol. Therap. 35, 224–230.

Fenoldopam is a selective dopamine‐1 receptor agonist that causes peripheral arterial vasodilation, increased renal blood flow, and diuresis. Enthusiasm exists for the use of fenoldopam in nonpolyuric kidney injury in dogs, although pharmacokinetic data are lacking. The purpose of this study was to collect basic pharmacokinetic and hemodynamic effect data for fenoldopam when administered to healthy awake dogs. Six healthy, awake beagles were given a 180‐min fenoldopam constant rate infusion at 0.8 μg/kg per minute followed by a 120‐min washout period. Citrated blood was collected during and after infusion for the measurement of plasma fenoldopam concentration by HPLC with mass spectrometry. Heart rate and indirect systolic blood pressure were concurrently measured. Mean ± SD, steady‐state plasma fenoldopam concentrations of 20 ± 17 ng/mL were achieved within 10 min of starting the infusion. Area under the plasma concentration–time curve was 3678 ± 3030 ng/mL·min, and plasma clearance was 66 ± 43 mL/min per kg. Elimination was rapidly achieved in all dogs. Heart rate and systolic blood pressure were unaffected by the fenoldopam infusion. Based on the results of this study, further evaluation of the effects of fenoldopam in dogs at differing doses and in dogs with clinical conditions such as acute nonpolyuric kidney injury is warranted.
Co‐ordination of quorum‐sensing regulation in Rhizobium leguminosarum by induction of an anti‐repressor
Authors: Frederix Marijke , Edwards Anne , McAnulla Craig , Downie J. Allan
Published: July 2011

Analysis of quorum‐sensing (QS) regulation in Rhizobium leguminosarum revealed an unusual type of gene regulation that relies on the population density‐dependent accumulation of an anti‐repressor. The cinS gene, which is co‐transcribed with the N‐acyl‐homoserine‐lactone synthase gene cinI, is required to fully induce rhiR and raiR, whose products, together with their partner AHL synthases, regulate other genes in a QS‐regulated hierarchy. Purified CinS bound to the R. leguminosarum transcriptional regulator PraR, which repressed rhiR and raiR expression. PraR bound to the rhiR and raiR promoters and CinS displaced PraR from these promoters, thereby inducing their expression. Although induction of cinS required CinI‐made AHL, it appears CinS does not require the AHL for its anti‐repressor function. The LuxR‐type regulator ExpR was also required for normal induction of rhiR and raiR and it appears that this occurs by ExpR repressing the transcription of praR. Therefore ExpR and CinS act independently to attenuate PraR action, ExpR by repressing its transcription and CinS by attenuating its repressive activity. Thus, as CinS accumulates in a population density‐dependent manner it induces the QS hierarchy by relieving PraR‐mediated repression of rhiR and raiR.
Transfusion tomorrow: Royal College of Pathologists, November 2010
Authors: Butler C. E. , Dickens E. L.
Published: July 2011

Introduction. Following on from 2009's successful meeting ‘Transfusion Today’, the Royal College of Pathologists presented another fascinating 2‐day symposium ‘Transfusion Tomorrow’ to consider the future impact of recent advances in transfusion medicine. Topics ranged from blood safety issues and regulation, through clinical and laboratory practice, to molecular advances in transfusion science. The meeting focussed on the evidence base for developments in clinical practice and drew in a wide cross‐section of scientific, clinical and technical staff.
Lack of intra‐laboratory reproducibility in using Platelia Aspergillus enzyme immunoassay test for detection of Aspergillus galactomannan antigen
Authors: Oren I. , Avidor I. , Sprecher H.
Published: July 2011

I. Oren, I. Avidor, H. Sprecher. Lack of intra‐laboratory reproducibility in using Platelia Aspergillus enzyme immunoassay test for detection of Aspergillus galactomannan antigen. Transpl Infect Dis 2011. All rights reserved
Effects of glucose, propionate and splanchnic hormones on neuropeptide mRNA concentrations in the ovine hypothalamus
Authors: Relling A. E. , Lee K. , Loerch S. C. , Reynolds C. K.
Published: July 2011

The capacity for glucose, propionate or hormones of splanchnic origin to influence appetite by directly regulating the expression of neuropeptides in the feeding centres of the hypothalamus of the ruminant is not described. Therefore, our objective was to measure the direct effect of metabolites (glucose and propionate) or hormones [insulin, cholecystokinin (CCK), glucagon‐like peptide‐1 (GLP‐1) and polypeptide YY (PYY)] on hypothalamic mRNA concentrations for neuropeptide Y (NPY), agouti‐related peptide (AgRP) and proopiomelanocortin (POMC) following in vitro incubation. Hypothalamic tissue from 4‐ to 5‐month‐old lambs was obtained at slaughter and immediately incubated in culture media for 2 h at 36 °C. Treatments included a control Dulbecco’s modified Eagle medium (DMEM) containing 1 mm glucose or DMEM with the following additions: 10 mm glucose, 1 mm propionate, 1 nm insulin, 120 pm GLP‐1, 100 pm PYY, 80 pm CCK or 10 mm glucose plus 1 nm insulin. The abundance of mRNA for NPY, AgRP and POMC was measured using quantitative reverse transcriptase PCR. Fisher’s protected LSD test was used to compare changes in relative mRNA concentrations for the hypothalamus incubated in the control media vs. the rest of the treatments. The media containing glucose plus insulin increased POMC mRNA concentration (p < 0.05), but did not affect NPY or AgRP mRNA concentration. There were no effects observed for the other treatments (p > 0.20). Results of the present study are consistent with the concept that effects of propionate on feed intake in ruminants is not mediated through direct effects on the hypothalamus, and that insulin is required for an effect of glucose on hypothalamic POMC expression.
ABCC1 polymorphism Arg723Gln (2168G > A) is associated with lung cancer susceptibility in a Chinese population
Authors: Yin Ji‐Ye , Han Li‐Fang , Huang Qiong , Xu Xiao‐Jing , Zhou Hong‐Hao , Liu Zhao‐Qian
Published: July 2011

1. In a previous in vitro study, we showed that the Arg723Gln (2168G > A) polymorphism significantly ABCC1‐induced multidrug resistance. The aim of the present study was to further investigate the association of this polymorphism with lung cancer susceptibility and chemotherapy response in a Chinese population.

2. A total of 77 lung cancer patients (54 men, 23 women) and 71 cancer‐free controls (49 men, 22 women) were enrolled in the study. Genomic DNA was extracted from peripheral blood and all samples were genotyped using polymerase chain reaction‐restriction fragment length polymorphism.

3. Individuals carrying the 723Gln (A) allele have a 3.4‐fold increased risk (adjusted odds ratio (OR) 3.42; 95% confidence interval (CI) 1.29–9.06; P = 0.013) of lung cancer compared with wild‐type individuals. Further stratified analysis indicated that older individuals (> 50 years) carrying the 723Gln (A) allele have the highest susceptibility to lung cancer (adjusted OR 4.10; 95% CI 1.25–13.48; P = 0.020). However, no substantial association was found between the Arg723Gln (2168G > A) polymorphism and chemotherapy response in Chinese lung cancer patients.

4. In conclusion, the Arg723Gln (2168G > A) polymorphism of ABCC1 appears to be a potential susceptibility marker for lung cancer in the Chinese population, especially in older people.