bluuebunny/crossref_metadata_2025 huggingface dataset:
Electrical characteristics of zinc oxide-organic semiconductor lateral heterostructure based hybrid field-effect bipolar transistors
Authors: Singh Samarendra P. , Ooi Zi-En , Geok Serene Ng Lay , Goh Gregory K. L. , Dodabalapur Ananth
Published: February 2011

Zinc oxide-organic semiconductor lateral heterostructure based field-effect bipolar transistors (FEBTs) having heterointerfaces approximately midway between the source and drain electrodes are fabricated and characterized. These hybrid FEBTs comprise zinc oxide (ZnO) and p-channel organic semiconductors [Pentacene and α-sexithiophene (6T)] supporting electron transport and hole transport on either side of the heterojunction, respectively. Current flow in the transistor channel is established as a result of carrier injection across the heterointerface followed by recombination. In steady state, such devices possess significant populations of holes and electrons in the transistor channel and operate in bipolar mode.
Development of effective power supply using electric double layer capacitor for static magnetic field coils in fusion plasma experiments
Authors: Inomoto M. , Abe K. , Yamada T. , Kuwahata A. , Kamio S. , Cao Q. H. , Sakumura M. , Suzuki N. , Watanabe T. , Ono Y.
Published: February 2011

A cost-effective power supply for static magnetic field coils used in fusion plasma experiments has been developed by application of an electric double layer capacitor (EDLC). A prototype EDLC power supply system was constructed in the form of a series LCR circuit. Coil current of 100 A with flat-top longer than 1 s was successfully supplied to an equilibrium field coil of a fusion plasma experimental apparatus by a single EDLC module with capacitance of 30 F. The present EDLC power supply has revealed sufficient performance for plasma confinement experiments whose discharge duration times are an order of several seconds.
Nanopattern enabled terahertz all-optical switching on vanadium dioxide thin film
Authors: Choi S. B. , Kyoung J. S. , Kim H. S. , Park H. R. , Park D. J. , Kim Bong-Jun , Ahn Y. H. , Rotermund F. , Kim Hyun-Tak , Ahn K. J. , Kim D. S.
Published: February 2011

We demonstrate ultrafast all-optical control of terahertz (THz) radiation through nanoresonators, slot antennas with a hundred micron length but submicron width in thin gold layers, fabricated on vanadium dioxide (VO2) thin films. Our THz nanoresonators show almost perfect transmission at resonance. By virtue of phase transition of VO2 from insulating to metallic state, induced in subpicosecond time scale by moderate optical pump, ultrafast control of THz transmission is enabled. This is compared to bare VO2 films where no switching dynamics are observed under similar conditions.
Multireference coupled-cluster study of the symmetry breaking in the $\rm {C_{2}B}$C2B radical
Authors: Li Xiangzhu , Paldus Josef
Published: February 2011

The potential energy surfaces (PESs) for both the ground and the excited electronic states of the C2B radical are investigated using various multireference (MR) coupled-cluster (CC) approaches. In the ground state case we employ the reduced MR (RMR) CC approach with singles (S) and doubles (D), the RMR CCSD method, as well as its RMR CCSD(T) version corrected for secondary triples, relying on various model spaces and basis sets. The reliability of this approach is also tested against the benchmark full configuration interaction results obtained for a small Dunning–Hay (DH) basis set. The results imply a clear preference for a cyclic structure which, however, breaks the C2v symmetry. This symmetry breaking manifests itself strongly at the level of the independent particle model, as represented by the restricted open-shell Hartree–Fock approximation, but the tendency toward symmetry breaking diminishes with the increasing size of the basis set employed as well as with the enhanced account of the correlation effects. It is likely to disappear in the complete basis set limit. The general model space CCSD method is then used to compute vertical excitation energies for a number of excited states as well as the cuts of the PES as the boron atom moves around the C2 fragment. These results also explain why no symmetry breaking is found when relying on a spin contaminated unrestricted Hartree–Fock reference, as in the UMP2 method.
Microhydration effects on the electronic spectra of protonated polycyclic aromatic hydrocarbons: [naphthalene-(H2O)n = 1,2]H+
Authors: Alata Ivan , Broquier Michel , Dedonder-Lardeux Claude , Jouvet Christophe , Kim Minho , Sohn Woon Yong , Kim Sang-su , Kang Hyuk , Schütz Markus , Patzer Alexander , Dopfer Otto
Published: February 2011

Vibrational and electronic spectra of protonated naphthalene (NaphH+) microsolvated by one and two water molecules were obtained by photofragmentation spectroscopy. The IR spectrum of the monohydrated species is consistent with a structure with the proton located on the aromatic molecule, NaphH+-H2O. Similar to isolated NaphH+, the first electronic transition of NaphH+-H2O (S1) occurs in the visible range near 500 nm. The doubly hydrated species lacks any absorption in the visible range (420–600 nm) but absorbs in the UV range, similar to neutral Naph. This observation is consistent with a structure, in which the proton is located on the water moiety, Naph-(H2O)2H+. Ab initio calculations for [Naph-(H2O)n]H+ confirm that the excess proton transfers from Naph to the solvent cluster upon attachment of the second water molecule.
Quantum mechanical study of the coupling of plasmon excitations to atomic-scale electron transport
Authors: Song Peng , Nordlander Peter , Gao Shiwu
Published: February 2011

The coupling of optical excitation and electron transport through a sodium atom in a plasmonic dimer junction is investigated using time-dependent density functional theory. The optical absorption and dynamic conductance is determined as a function of gap size. Surface plasmons are found to couple to atomic-scale transport through several different channels including dipolar, multipolar, and charge transfer plasmon modes. These findings provide insight into subnanoscale couplings of plasmons and atoms, a subject of general interest in plasmonics and molecular electronics.
Molecular simulations of confined liquids: An alternative to the grand canonical Monte Carlo simulations
Authors: Ghoufi Aziz , Morineau Denis , Lefort Ronan , Hureau Ivanne , Hennous Leila , Zhu Haochen , Szymczyk Anthony , Malfreyt Patrice , Maurin Guillaume
Published: February 2011

Commonly, the confinement effects are studied from the grand canonical Monte Carlo (GCMC) simulations from the computation of the density of liquid in the confined phase. The GCMC modeling and chemical potential (μ) calculations are based on the insertion/deletion of the real and ghost particle, respectively. At high density, i.e., at high pressure or low temperature, the insertions fail from the Widom insertions while the performing methods as expanded method or perturbation approach are not efficient to treat the large and complex molecules. To overcome this problem we use a simple and efficient method to compute the liquid's density in the confined medium. This method does not require the precalculation of μ and is an alternative to the GCMC simulations. From the isothermal–isosurface–isobaric statistical ensemble we consider the explicit framework/liquid external interface to model an explicit liquid's reservoir. In this procedure only the liquid molecules undergo the volume changes while the volume of the framework is kept constant. Therefore, this method is described in the NpnAVfT statistical ensemble, where N is the number of particles, pn is the normal pressure, Vf is the volume of framework, A is the surface of the solid/fluid interface, and T is the temperature. This approach is applied and validated from the computation of the density of the methanol and water confined in the mesoporous cylindrical silica nanopores and the MIL-53(Cr) metal organic framework type, respectively.
On the classification of scalar evolutionary integrable equations in 2 + 1 dimensions
Authors: Novikov V. S. , Ferapontov E. V.
Published: February 2011

We consider evolutionary equations of the form ut = F(u, w) where \documentclass[12pt]{minimal}\begin{document}$w=D_x^{-1}D_yu$\end{document}w=Dx−1Dyu is the nonlocality, and the right hand side F is polynomial in the derivatives of u and w. The recent paper [Ferapontov, Moro, and Novikov, J. Phys. A: Math. Theor. 52, 18 (2009)] provides a complete list of integrable third order equations of this kind. Here we extend the classification to fifth order equations. Besides the known examples of Kadomtsev–Petviashvili, Veselov–Novikov, and Harry Dym equations, as well as fifth order analogs and modifications thereof, our list contains a number of equations which are apparently new. We conjecture that our examples exhaust the list of scalar polynomial integrable equations with the nonlocality w. The classification procedure consists of two steps. First, we classify quasilinear systems which may (potentially) occur as dispersionless limits of integrable scalar evolutionary equations. After that we reconstruct dispersive terms based on the requirement of the inheritance of hydrodynamic reductions of the dispersionless limit by the full dispersive equation.
Charge transport, carrier balance, and blue electrophosphorescence in diphenyl[4-(triphenylsilyl)phenyl]phosphine oxide devices
Authors: Mamada Masashi , Ergun Selin , Pérez-Bolívar César , Anzenbacher Pavel
Published: February 2011

Diphenyl[4-(triphenylsilyl)phenyl]phosphine oxide (EMPA1) displays a wide highest occupied molecular orbital–lowest unoccupied molecular orbital gap (4.1 eV), singlet (4.3 eV) and triplet (3.4 eV), and an electron-dominated charge transport that follows a trap-free space charge limited model with an average electron mobility of 5.7×10−6 cm2 V−1 s−1 and a hole mobility of 1.1×10−6 cm2 V−1 s−1. At high driving voltages (>6 V), ambipolar charge transport is observed, resulting in a balanced charge density in the active layer. Highly efficient blue phosphorescent organic light-emitting diodes were realized, showing a high external quantum efficiency (21%) and a luminance efficiency of 45 cd/A using a bis[2-(4′,6′-difluorophenyl)-pyridinato-N,C2′]iridium(III) picolinate dopant.
Guided self-assembly of unidirectionally oriented quasi-one-dimensional 3,4,9,10–perylene-tetracarboxylic-dianhydride chains using surface nanowires
Authors: Wei Zheng , Lim Heechul , Lee Geunseop
Published: February 2011

A quasi-one-dimensional chains of 3,4,9,10-perylene-tetracarboxylic-dianhydride (PTCDA) molecules are grown by using nanowire arrays on a In/Si(111)-(4×1) surface as a template. The PTCDA molecules self-assemble in a “head-and-tail” configuration with their long axis aligned with the direction of the surface nanowires. This unidirectional orientation is unique and indicates that the molecular arrangement is not governed by hydrogen bonding which prevails in the self-assembly of the PTCDA molecules on two-dimensional surfaces. Existence of weak and short-ranged interchain molecular interactions is also deduced, revealing the quasi-one-dimensional character of the molecular chains.
Stretchable fine fiber with high conductivity fabricated by injection forming
Authors: Wakuda Daisuke , Suganuma Katsuaki
Published: February 2011

Stretchable conductors are necessary to realize soft and rubbery electronics. A stretchable fine fiber with high conductivity was fabricated by a injection forming. The fiber is made of silicone series conductive adhesive containing Ag flake fillers. The fiber has uniform diameter without any substrate and has very long length by the injection forming method. The diameters can be controlled by changing the bore diameter of the injection needle. Furthermore, the fine fiber, 230 μm in diameter, maintains excellent conductivity under cyclic tensile stress. The conductivity is approximately 470 S/cm without tensile stress and maintains over 90 S/cm under cyclic tensile test which is stretched up to 10% strain. The result exhibits a great potential of the conductive fine fiber as a stretchable conductor.
Nucleation and coalescence effects on the density of self-induced GaN nanowires grown by molecular beam epitaxy
Authors: Consonni V. , Knelangen M. , Trampert A. , Geelhaar L. , Riechert H.
Published: February 2011

The evolution of the density of self-induced GaN nanowires as a function of the growth time, gallium rate, and growth temperature has been investigated by scanning and transmission electron microscopy. Nucleation and coalescence effects have been disentangled and quantified by distinguishing between single nanowires and nanowire clusters. Owing to the very specific nanowire nucleation mechanism involving a shape transition from spherical-cap-shaped islands, the nanowire density does not follow the standard island nucleation theory. Furthermore, the detrimental nanowire coalescence process can be significantly reduced by raising the growth temperature.
High resolution magnetic vector-field imaging with cold atomic ensembles
Authors: Koschorreck M. , Napolitano M. , Dubost B. , Mitchell M. W.
Published: February 2011

We present a magnetic field imaging technique based on spatially resolved detection of Larmor precession. An optically trapped, elongated, and cold atomic sample of rubidium serves as magnetic field probe. We detect Larmor precession with a spatial and a temporal resolution of ∼50μm and ∼120μs, respectively. Projection-noise limited absorption imaging, feasible with current technologies, implies a sensitivity of ∼10pT/Hz at 50μm resolution; addition of an optical lattice could give ∼300fT/Hz sensitivity.
Control of device parameters by active layer thickness in organic field-effect transistors
Authors: Kano Masataka , Minari Takeo , Tsukagoshi Kazuhito , Maeda Hiroki
Published: February 2011

We investigate the effect of the parasitic access resistance on device parameters, particularly the threshold voltage (VT) and the contact resistance (RC), of staggered organic field-effect transistors by varying the active layer thickness (ds). At low gate voltages, RC decreases as ds increases due to the free carrier density increasing in the semiconductor film. At high gate voltages, RC increases as ds increases due to increasing access resistance. These factors degrade the device parameters with increasing ds. The contribution of the change in ds on the VT shift is assessed by subtracting the contact effect from the apparent VT.
Josephson tunnel junctions in a magnetic field gradient
Authors: Monaco R. , Mygind J. , Koshelets V. P.
Published: February 2011

We measured the magnetic field dependence of the critical current of high-quality Nb-based planar Josephson tunnel junctions in the presence of a controllable nonuniform field distribution. We found skewed and slowly changing magnetic diffraction patterns quite dissimilar from the Fraunhofer-like ones typical of a homogeneous field. Our findings can be well interpreted in terms of recent theoretical predictions [R. Monaco, J. Appl. Phys. 108, 033906 (2010)] for a uniform magnetic field gradient, leading to Fresnel-like magnetic diffraction patterns. We also show that Fiske resonances can be suppressed by an asymmetric magnetic field profile.
Permanent photoalignment of liquid crystals on nanostructured chalcogenide glassy thin films
Authors: Gelbaor Miri , Klebanov Matvey , Lyubin Victor , Abdulhalim I.
Published: February 2011

Photoalignment of nematic liquid crystals is obtained on the chalcogenide glassy thin film of As2S3 using irradiation with polarized blue light. A uniform homogeneously aligned device is obtained with high contrast and strong anchoring. The device alignment quality is permanent as checked by following its functionality over a period of few months. The origin of the observed photoalignment is attributed to the photoinduced anisotropy in chalcogenide glasses. No differences between the different As2S3 film thicknesses observed, thus supporting the proposition that some orientational order is photoinduced on the surface of the glass and responsible for the photoalignment.
Flux requirements for the growth of RFeAsO (R=rare earth) superconductors
Authors: Yan J.-Q. , Jensen B. , Dennis K. W. , McCallum R. W. , Lograsso T. A.
Published: February 2011

Millimeter-sized LaFeAsO single crystals have been successfully grown out of NaAs flux starting with (LaAs+1/2Fe2O3):20NaAs. The factors which allow the growth of these crystals out of NaAs but not out of many other fluxes, such as FeAs, have been investigated. X-ray powder diffraction found that NaAs synthesized for the growth of RFeAsO superconductors has monoclinic LiAs structure. Thermal analysis confirmed that NaAs melts congruently at about 600 °C. The ability to extract RFeAsO crystals from this NaAs flux suggests that NaAs has a significant oxygen solubility, possibly due to the formation of the ternary compound NaAsO2, and enough oxygen diffusivity to transport solute to the growth front. Oxygen solubility and diffusivity are two important factors in searching for an alternative environmentally benign flux for the growth of RFeAsO superconductors.
Biplot analysis of diallel crosses for cold tolerance in rice at the germination stage
Authors: Sharifi Peyman , Motlagh Mohammad Reza Safari
Published: February 2011

This paper reports analysis of 7 × 7 diallel crosses using a genotype main effect plus genotype-by-environment interaction biplot for determining cold tolerance at the germination stage in rice. ANOVA indicated that there were highly significant differences among the replications, genotypes, general combining ability (GCA) and specific combining ability (SCA) for percentage of reduction in radicle length (RL), coleoptile length (CL) and germination percentage (GP). The hybrid Neda × Hassani had the highest mid-parent heterosis for RL, CL and GP (–58.84, –68.47 and –80.77%, respectively). This result indicated that the reduction of three traits in crosses of Neda × Hassani was lower than their parents. The graphical representation by biplot analysis allowed a rapid and effective overview of GCA and reveals that Deilamani was an ideal general combiner for all traits and this parent is a superior variety for these three traits. Three potential heterotic groups are suggested for RL reduction. Four potential heterotic groups were identified for the two other traits, in the biplot. The first two principal component (PC) axes in the biplot for reduction in GP explained 85% of the variation with first and second principal components (PC1 and PC2, respectively). An important inference that can be drawn from these results is that cross combinations involving Hassani and Deilamani as one of the parents recorded desirable SCA effects for all or most of the studied traits. The information obtained from this experiment can facilitate the identification of hybrids that combine cold resistance traits in rice.
Claudin-4 induction by E-protein activity in later stages of CD4/8 double-positive thymocytes to increase positive selection efficiency
Authors: Kawai Yohei , Hamazaki Yoko , Fujita Harumi , Fujita Akikazu , Sato Takehito , Furuse Mikio , Fujimoto Toyoshi , Jetten Anton M. , Agata Yasutoshi , Minato Nagahiro
Published: February 2011

Claudins (Clds) are crucial constituents of tight-junction strands in epithelial cells and have a central role in barrier functions. We show that Cld4 is unexpectedly expressed in normal thymic lymphocytes independently of tight junctions. The Cld4 expression was mostly confined to a portion of the CD4/CD8 double-positive (DP) cells. The proportion of Cld4
+
DP cells was markedly increased in MHC-I
−/−
II
−/−
mice but decreased in Rorγ
−/−
mice, and Cld4
+
DP cells contained higher levels of the rearranged
Tcra
transcripts involving the most distal
Va
and
Ja
segments than Cld4
–
DP cells. The Cld4 expression levels were reduced in E47-deficient mice in a gene dose-dependent manner, and ChIP analysis indicated that E2A and HEB were bound to the E-box sites of the putative
Cldn4
promoter region. Functionally, Cld4 showed a potent T-cell receptor costimulatory activity by coligation with CD3. The Cld4 was distributed diffusely on the cell surface and associated with CD4/lck independently of CD3 in the resting thymocytes. However, Cld4 was strongly recruited to the immunological synapse on specific T-cell receptor engagement through antigen-presenting cells. In the fetal thymic organ culture, knockdown of
Cldn4
resulted in the reduced generation of CD4/CD8 single-positive cells from the DP cells. These results suggest that Cld4 is induced by E-protein activity in the later stages of DP cells to increase the efficiency of positive selection, uncovering a hitherto unrecognized function of a Cld family protein.
Cortisone-reductase deficiency associated with heterozygous mutations in 11β-hydroxysteroid dehydrogenase type 1
Authors: Lawson Alexander J. , Walker Elizabeth A. , Lavery Gareth G. , Bujalska Iwona J. , Hughes Beverly , Arlt Wiebke , Stewart Paul M. , Ride Jonathan P.
Published: February 2011

In peripheral target tissues, levels of active glucocorticoid hormones are controlled by 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), a dimeric enzyme that catalyzes the reduction of cortisone to cortisol within the endoplasmic reticulum. Loss of this activity results in a disorder termed cortisone reductase deficiency (CRD), typified by increased cortisol clearance and androgen excess. To date, only mutations in
H6PD
, which encodes an enzyme supplying cofactor for the reaction, have been identified as the cause of disease. Here we examined the
HSD11B1
gene in two cases presenting with biochemical features indicative of a milder form of CRD in whom the
H6PD
gene was normal. Novel heterozygous mutations (R137C or K187N) were found in the coding sequence of
HSD11B1
. The R137C mutation disrupts salt bridges at the subunit interface of the 11β-HSD1 dimer, whereas K187N affects a key active site residue. On expression of the mutants in bacterial and mammalian cells, activity was either abolished (K187N) or greatly reduced (R137C). Expression of either mutant in a bacterial system greatly reduced the yield of soluble protein, suggesting that both mutations interfere with subunit folding or dimer assembly. Simultaneous expression of mutant and WT 11β-HSD1 in bacterial or mammalian cells, to simulate the heterozygous condition, indicated a marked suppressive effect of the mutants on both the yield and activity of 11β-HSD1 dimers. Thus, these heterozygous mutations in the
HSD11B1
gene have a dominant negative effect on the formation of functional dimers and explain the genetic cause of CRD in these patients.
Structural basis for nonribosomal peptide synthesis by an aminoacyl-tRNA synthetase paralog
Authors: Bonnefond Luc , Arai Taiga , Sakaguchi Yuriko , Suzuki Tsutomu , Ishitani Ryuichiro , Nureki Osamu
Published: February 2011

Cyclodipeptides are secondary metabolites biosynthesized by many bacteria and exhibit a wide array of biological activities. Recently, a new class of small proteins, named cyclodipeptide synthases (CDPS), which are unrelated to the typical nonribosomal peptide synthetases, was shown to generate several cyclodipeptides, using aminoacyl-tRNAs as substrates. The
Mycobacterium tuberculosis
CDPS, Rv2275, was found to generate cyclodityrosine through the formation of an aminoacyl-enzyme intermediate and to have a structure and oligomeric state similar to those of the class Ic aminoacyl-tRNA synthetases (aaRSs). However, the poor sequence conservation among CDPSs has raised questions about the architecture and catalytic mechanism of the identified homologs. Here we report the crystal structures of
Bacillus licheniformis
CDPS YvmC-Blic, in the apo form and complexed with substrate mimics, at 1.7–2.4-Å resolutions. The YvmC-Blic structure also exhibits similarity to the class Ic aaRSs catalytic domain. Our mutational analysis confirmed the importance of a set of residues for cyclodileucine formation among the conserved residues localized in the catalytic pocket. Our biochemical data indicated that YvmC-Blic binds tRNA and generates cyclodileucine as a monomer. We were also able to detect the presence of an aminoacyl-enzyme reaction intermediate, but not a dipeptide tRNA intermediate, whose existence was postulated for Rv2275. Instead, our results support a sequential catalytic mechanism for YvmC-Blic, with the successive attachment of two leucine residues on the enzyme via a conserved serine residue. Altogether, our findings suggest that all CDPS enzymes share a common aaRS-like architecture and a catalytic mechanism involving the formation of an enzyme-bound intermediate.
Emergency Contraception
Authors: Masson Clifford
Published: February 2011

Unintended pregnancy is a major public health issue with around 53 million abortions being performed worldwide each year. An estimated 40% of all pregnancies are unplanned and 60% of these end in abortion. Rates of unplanned pregnancy and abortion remain high in the UK compared with other European countries and each year around 200 000 pregnancies in the UK end in termination. Use of emergency contraception (EC) has the potential to reduce rates of unwanted pregnancy. With around a third of all EC prescriptions issued in primary care, the GP and primary health care team have a major role in the provision of a sexual health and EC.
Asthma in Children
Authors: Hogg Andrew , Simon Chantal
Published: February 2011

The diagnosis and management of childhood asthma is an essential skill for GPs. Asthmatic children and their families bring with them their own unique set of diagnostic and managerial problems when compared with adults. This article seeks to provide clear guidance on the diagnosis of asthma in children and a summary of management options including when to escalate therapy, use of different drug delivery devices and indications for referral.
Effect of Flour‐Blasting Brown Rice on Reduction of Cooking Time and Resulting Texture
Authors: Guraya Harmeet S.
Published: February 2011

Long‐grain nonparboiled, long‐grain parboiled, and American basmati‐type brown rice were bombarded with parboiled rice flour particles to create microperforations on the water‐resistant outer layer of the kernels. These microperforations in the treated rice significantly increased the rate of hydration. Optimum conditions to produce microperforations without removal of the bran included air pressure maintained at 413 kPa and a parboiled rice flour average particle size of 124 μm. The optimum blasting time was 40–60 sec, depending on the type of rice. The relative hardness of the fully cooked flour‐blasted rice was the same at half the cooking time of the untreated brown rice but % water absorption of the untreated flour‐blasted brown rice was higher because it required longer time to cook. Overall, untreated brown rice was ≈4.7% higher in % water absorption due to longer cooking time in comparison with the treated counterpart. The blasting treatment resulted in shorter cooking time and firmer and less gummy cooked rice as compared to freshly cooked untreated brown rice.
Development of a Benchtop Baking Method for Chemically Leavened Crackers II. Validation of the Method
Authors: Kweon Meera , Slade Louise , Levine Harry
Published: February 2011

A benchtop baking method has been developed to predict the contribution of gluten functionality to overall flour performance for chemically leavened crackers. Using a diagnostic formula and procedure, dough rheology was analyzed to evaluate the extent of gluten development during mixing and machining. The effects of enzymes on cracker‐baking performance were explored to assess the impact of damaged starch and pentosans (arabinoxylans). Validation of the method for predicting gluten functionality and performance was conducted using various flours. Cracker dough rheology, measured in the direction of sheeting, showed a positive correlation with the ratio of cracker height to dough weight, but a negative correlation with the ratio of cracker width to length. Use of α‐amylase and xylanase demonstrated the improving effects of enzymes on cracker‐baking performance of flour resulting from decreased dough crumbliness and increased cracker height. Flour gluten performance ratio of lactic acid solvent retention capacity (LA SRC)/(sodium carbonate [SC] SRC + sucrose [Suc] SRC) (SRC LA/[SC+Suc]) was a better predictor of cracker geometry than was flour gluten functionality value of LA SRC alone. Flours with a gluten performance ratio of <0.52 produced unacceptable, excessive blistering during cracker baking.
Characterization of Botrytis cinerea Isolates Present in Thompson Seedless Table Grapes in the Central Valley of Chile
Authors: Esterio Marcela , Muñoz Gastón , Ramos Cecilia , Cofré Gonzalo , Estévez Rodrigo , Salinas Andrea , Auger Jaime
Published: February 2011

Botrytis cinerea isolates from flowers and berries of Vitis vinifera ‘Thompson seedless’ (grapevine) were characterized in terms of two transposable elements (TEs) Boty and Flipper, random amplified polymorphic DNA (RAPD), infection levels, and resistance to iprodione. The isolates were collected from grapevines under fungicide programs of variable numbers of iprodione applications, and replicated in three Chilean Central Valley locations. Recovery was repeated from clusters collected at four phenological stages. Highest infection levels were found at bloom. Fungicide programs including one iprodione application or a combination of other fungicides were most effective for reducing gray mold symptoms. A total of 457 isolates collected from fungicide programs including only one iprodione application, and the control program, were tested for the presence of TEs. In all locations and during all phenological stages, transposa isolates (containing both TEs) were most common, followed by Boty. Vacuma isolates (containing neither TE) were identified at very low levels in two locations and only in the control treatment, and isolates with only Flipper were not detected at any time or location. Vacuma and Boty isolates were all sensitive to iprodione, while transposa isolates showed a wide range of resistance. Based on response to iprodione, the presence of TEs, and presence of vegetative-incompatibility alleles (Bc-hch), the isolates studied belong to B. cinerea Group II, a phylogenetic species within B. cinerea. Hierarchical analysis of molecular variance and genetic diversity analyses of the RAPD genotypes showed a genetic differentiation linked to location, but it was not related to geographic distance. Moreover, a genetic differentiation related to the phenological stage of grapes was also detected.
Presence of Fusarium spp. in Air and Soil Associated with Sorghum Fields
Authors: Funnell-Harris Deanna L. , Pedersen Jeffrey F.
Published: February 2011

Sorghum grain, valuable for feed, food, and bioenergy, can be colonized by several Fusarium spp.; therefore, it was of interest to identify possible sources of conidia. Analysis of air and soil samples provided evidence for the presence of propagules from Fusarium genotypes that may cause grain infections. Soil population estimates of members of the Gibberella fujikuroi species complex, that includes sorghum pathogens and other Fusarium spp., suggested that adequate inoculum for systemic infections was present. Conidia in air samples within two sorghum fields were collected by passive trapping for 2 years. Subsampled Fusarium isolates indicated that numbers of G. fujikuroi increased from anthesis through maturity, which coincides with grain development stages vulnerable to Fusarium spp. Genotyping using translation elongation factor 1-α gene sequences revealed that spore trap isolates included members of G. fujikuroi that are sorghum pathogens: Fusarium thapsinum, F. verticillioides, F. proliferatum, and F. andiyazi. Also detected were F. graminearum, F. subglutinans, and several F. incarnatum-F. equiseti species complex haplotypes that colonize sorghum asymptomatically. All commonly found grain colonizers were detected from air samples in this study.
Competitive Parasitic Fitness of Mefenoxam-Sensitive and -Resistant Isolates of Phytophthora erythroseptica under Fungicide Selection Pressure
Authors: Chapara Venkataramana , Taylor Raymond J. , Pasche Julie S. , Gudmestad Neil C.
Published: February 2011

A 2-year field and laboratory experiment was initiated to study the competitive parasitic fitness of mefenoxam-resistant (50% effective concentration [EC50] > 100 μg ml–1) and mefenoxam-sensitive (EC50 = 0.07 μg ml–1) isolates of Phytophthora erythroseptica with equal aggressiveness. The competitive ability of the mefenoxam-resistant and -sensitive isolates was tested under no selection pressure (nonfungicide treated) as well as under the influence of mefenoxam and non-mefenoxam (phosphorous acid) fungicides. P. erythroseptica isolates were combined in four ratios of mefenoxam-resistant (R) to mefenoxam-susceptible (S) (0R:0S, 1R:1S, 3R:1S, and 1R:3S) and subsequently infested into the soil at the time of planting. In-furrow mefenoxam applications were applied to the soil immediately following infestation with P. erythroseptica. Phosphorous acid was applied at tuber initiation and 14 days after tuber initiation. Noninfested, nonfungicide-treated plots served as controls. P. erythroseptica isolates recovered from field-infected pink rot tubers at harvest and 3 to 4 weeks after harvest were tested for mefenoxam sensitivity in vitro. In vivo studies were performed by challenge inoculating a zoospore suspension in the four ratios described above onto potato tubers harvested from nontreated, phosphorous acid-treated, or mefenoxam-treated field plots. These field plots were not infested with P. erythroseptica at planting. Results from both field and in vivo studies demonstrate that mefenoxam-resistant isolates of P. erythroseptica are as fit as sensitive isolates in the absence of selection pressure or in the presence of a phosphorous acid fungicide treatment. Under mefenoxam selection pressure, mefenoxam-resistant P. erythroseptica isolates were more parasitically fit than -sensitive isolates. These studies suggest the lack of an apparent fitness penalty in mefenoxam-resistant P. erythroseptica populations under field conditions and that these isolates could be stable in most agroecological systems. Based on these results, mefenoxam-based fungicides are no longer recommended for the management of pink rot once mefenoxam-resistant P. erythroseptica populations are detected in a specific field.
Molecular Characterization of ‘Candidatus Phytoplasma asteris’ Associated with Aster Yellows-Diseased Potatoes in China
Authors: Cheng M. , Dong J. , Laski P. J. , Zhang Z. , McBeath J. H.
Published: February 2011

Potatoes (Solanum tuberosum) are one of the most important crops in China following rice, wheat, and corn. Aster yellows phytoplasma appeared to be widespread in China; it was found to cause diseases on alfalfa, oranges, peaches, periwinkles, bamboo (1), and cactus (4). However, scant information of this pathogen on potatoes is available except for a few short reports published during the 1950s. During the potato disease surveys conducted from 2005 to 2010 in Yunnan and Inner Mongolia, 10 to 35% of potato plants exhibited symptoms of yellowing or purpling of apical leaves, with the top leaves rolling inward and aerial tubers formation. Total DNA was extracted from midveins of leaves and roots of 125 diseased and asymptomatic plants with a DNeasy Plant Mini Kit (Qiagen, Valencia, CA) according to the manufacturer's instructions. A nested PCR was carried out with the first round primer pair P1/P7 followed by the second round primer pair R16F2n/R16R2 (2,3). A PCR product of approximately 1.2 kb was amplified from diseased plants but not from asymptomatic plants. Restriction fragment length polymorphism (RFLP) patterns were analyzed by digesting a 1.2-kb product using restriction enzymes AluI, BfaI, BstUI, HhaI, HpaI, KpnI, MseI, and RsaI. Comparing the RFLP patterns with previously published phytoplasma strains (2), aster yellows phytoplasma found on potato plants in Yunnan and Inner Mongolia belong to group I, subgroup B (16SrI-B). The PCR product from P1/P7, diluted 1:30, was amplified by using primer pair P1A/P7A (3) and P1A/16S-SR (3). The nested-PCR products from P1A/P7A and P1A/16S-SR were cloned into pCR8/GW/TOPO vector (Invitrogen, Carlsbad, CA) and sequenced by the Core Lab of the University of Alaska–Fairbanks and GENEWIZ (South Plainfield, NJ). The nucleotide sequence (GenBank Accession No. HQ599228) was analyzed by iPhyClassifier software and had 99.53% sequence identity to the reference strain (GenBank Accession No. M30790) for ‘Candidatus Phytoplasma asteris’. The RFLP similarity is identical (coefficient 1.00) to the reference pattern of 16Sr group I, subgroup B (GenBank Accession No. NC_005303). To our knowledge, this is the first report revealing the molecular characteristics of a phytoplasma associated with aster yellows-diseased potatoes in China.

References: (1) H. Cai et al. Plant Prot. 31:38, 2005. (2) I.-M. Lee et al. Int. J. Syst. Bacteriol. 48:1153, 1998. (3) I.-M. Lee et al. Int. J. Syst. Evol. Microbiol. 54:337, 2004. (4) W. Wei et al. Plant Dis. 91:461, 2007.
Control of Postharvest Botrytis Fruit Rot of Strawberry by Volatile Organic Compounds of Candida intermedia
Authors: Huang R. , Li G. Q. , Zhang J. , Yang L. , Che H. J. , Jiang D. H. , Huang H. C.
Published: February 2011

A study was conducted to identify volatile organic compounds or volatiles produced by Candida intermedia strain C410 using gas chromatography–mass spectrometry, and to determine efficacy of the volatiles of C. intermedia in suppression of conidial germination and mycelial growth of Botrytis cinerea and control of Botrytis fruit rot of strawberry. Results showed that, among 49 volatiles (esters, alcohols, alkenes, alkanes, alkynes, organic acids, ketones, and aldehydes) identified from C. intermedia cultures on yeast extract peptone dextrose agar, two compounds, 1,3,5,7-cyclooctatetraene and 3-methyl-1-butanol, were the most abundant. Synthetic chemicals of 1,3,5,7-cyclooctatetraene; 3-methyl-1-butanol; 2-nonanone; pentanoic acid, 4-methyl-, ethyl ester; 3-methyl-1-butanol, acetate; acetic acid, pentyl ester; and hexanoic acid, ethyl ester were highly inhibitory to conidial germination and mycelial growth of B. cinerea. Inhibition of conidial germination and mycelial growth of B. cinerea by volatiles of C. intermedia was also observed. Meanwhile, results showed that incidence and severity of Botrytis fruit rot of strawberry was significantly (P < 0.01) reduced by exposure of the strawberry fruit to the volatiles from C. intermedia cultures or C. intermedia-infested strawberry fruit. These results suggest that the volatiles of C. intermedia C410 are promising biofumigants for control of Botrytis fruit rot of strawberry.
Uni-Incisional Video-Assisted Thoracoscopic Left Lower Lobectomy in a Patient with an Incomplete Fissure
Authors: Gonzalez Diego , Delgado Maria , Paradela Marina , Fernandez Ricardo
Published: February 2011

Video-assisted thoracoscopic surgery (VATS) was introduced nearly two decades ago. Since then, there has been a rapid development in minimal invasive techniques for lung cancer treatment. The common approach is the one performed through three incisions, including a utility incision of ~3 to 5 cm. However, lobectomy can be performed by using only two incisions (one camera port and working incision). A few clinics perform this approach. We began the two-incision technique in our institution in February 2009. After performing 95 cases with this technique, we observed that for lower lobes the second incision could be eliminated, and we performed the surgery by using only the 4-cm utility incision. This article describes a case report of a 57-year-old woman operated by this uni-incisional approach for a lower lobe video-assisted thoracoscopic surgery lobectomy.
Regional Lung Chemotherapy Techniques
Authors: Mallick Reema , Demmy Todd
Published: February 2011

Selective delivery of chemotherapy to an affected organ or region of the body promises improved drug efficacy for the targeted area while minimizing the systemic exposure and toxicity. Several intravascular surgical techniques to achieve targeted regional lung chemotherapy have been developed. Investigations have been carried out to determine the feasibility, safety, and efficacy of these techniques in the primary or adjuvant setting with the intent to palliate or cure. This overview describes the history, rationale, technical aspects, and clinical experience of four regional lung chemotherapy techniques delivered by vascular manipulations including bronchial artery infusion, pulmonary artery chemoembolization, isolated lung perfusion, and lung suffusion.
Is Transthoracic Minimally Invasive Aortic Valve Replacement Too Time-Consuming for the Busy Cardiac Surgeon?
Authors: Cunningham Mark J. , Berberian Christopher E. , Starnes Vaughn A.
Published: February 2011

Objective

Transthoracic minimally invasive aortic valve replacement (TMI-AVR) is gaining popularity despite criticism that time from incision to the initiation of cardiopulmonary bypass (exposure time, ET), cardiopulmonary bypass time (CPBT), and cross-clamp time (XCT) is excessive. Database analysis was used to characterize these parameters and their associated learning curves.

Methods

From 2004 to 2008, 101 patients underwent TMI-AVR at a single institution. Of them, 54 were men (53%) and 47 were women (47%). Mean age was 70 years (range, 24–90 years). ET includes 6-cm incision, second intercostals anterior thoracotomy, medial transection of the third rib, opening pericardial sac, retracing pericardium with stay sutures, placing aortic arterial, and right arterial venous bypass cannulae. ET, CPBT, XCT, and operating room times were calculated. Logarithmic trend analysis established associated learning curves.

Results

ET steadily improved over time. ET decreased from an average of 51 minutes for the first 25 patients to 39 minutes for the most recent 25 patients. When surgeon experience reached 10 procedures, the ET trend line began to decline steadily and plateaued by 55 cases. Cross-clamp (55 ± 21 minutes), cardiopulmonary bypass (77 ± 31 minutes), and operating room times (304 ± 67 minutes) all remained constant. There were no early deaths or conversions to sternotomy.

Conclusions

ET learning curve for TMI-AVR was reflected after 10 procedures with continued gradual improvement. Reliability of TMI-AVR was observed in the absence of a learning curve for XCT, CPBT, and operating room times. A sternal-sparing transthoracic approach for AVR can be performed safely, with expected operative times equivalent to sternotomy.
A Novel Design of Posterior Leaflet Butterfly Resection for Mitral Valve Repair
Authors: Asai Tohru , Kinoshita Takeshi , Nishimura Osamu , Kambara Atsushi , Suzuki Tomoaki , Matsubayashi Keiji
Published: February 2011

A new design for posterior leaflet resection, “butterfly resection,” is proposed. It is a combination of two triangular resections in the prolapsing posterior leaflet segment. This method minimizes resection in the target segment, and it prevents systolic anterior motion by reducing the height of the posterior leaflet according to the amount of excess tissue. We have used this technique for 60.4% (29 of 48) of posterior leaflet prolapse cases with zero hospital mortality and no morbidity. Postbypass transesophageal echocardiography identified no more than mild regurgitation and no sign of systolic anterior motion. During 13.1 ± 6.8 months of follow-up, patients neither died nor needed reoperation.
On the vapour trail of an atmospheric imprint in insects
Authors: Ellwood M. D. Farnon , Northfield Roger G. W. , Mejia-Chang Monica , Griffiths Howard
Published: February 2011

Terrestrial arthropods, at constant risk from desiccation, are highly sensitive to atmospheric temperature and humidity. A physiological marker of these abiotic conditions could highlight phenotypic adaptations, indicate niche partitioning, and predict responses to climate change for a group representing three-quarters of the Earth's animal species. We show that the18O composition of insect haemolymph is such a measure, providing a dynamic and quantitatively predictable signal for respiratory gas exchange and inputs from atmospheric humidity. Using American cockroaches (Periplaneta americana) under defined experimental conditions, we show that insects respiring at low humidity demonstrate the expected enrichment in the18O composition of haemolymph because of evaporation. At high humidity, however, diffusionalinfluxof atmospheric water vapour into the animal forces haemolymph to become depleted in18O. Additionally, using cockroaches sampled from natural habitats, we show that the haemolymph18O signature is transferred to the organic material of the insect's exoskeleton. Insect cuticle, therefore, exhibits the mean atmospheric conditions surrounding the animals prior to moulting. This discovery will help to define the climatic tolerances of species and their habitat preferences, and offers a means of quantifying the balance between niche partitioning and ‘neutral’ processes in shaping complex tropical forest communities.
Understanding testosterone variation in a tropical lek-breeding bird
Authors: Ryder Thomas B. , Horton Brent M. , Moore Ignacio T.
Published: February 2011

Male reproductive coalitions, in which males cooperate to attract females, are a rare strategy among vertebrates. While some studies have investigated ultimate aspects of these relationships, little is known about the mechanistic role that hormones play in modulating cooperative behaviours. Here, we examined male testosterone variation in a tropical lekking bird, the wire-tailed manakin (
Pipra filicauda
), which exhibits cooperative male–male display coalitions. We found that testosterone levels in territorial males were comparable to those of temperate breeding birds, a surprising result given their environmental, social and reproductive dynamics. In addition, social status rather than plumage was a strong predictor of testosterone variation. Territorial males had significantly higher testosterone levels than did two other plumage classes of floater males, who do not hold territories. We hypothesize that testosterone variation plays an important role in the establishment of male dominance hierarchies (competition), while concurrently facilitating stable display partnerships (cooperation).
Ecosystem approach to inland fisheries: research needs and implementation strategies
Authors: Beard T. Douglas , Arlinghaus Robert , Cooke Steven J. , McIntyre Peter B. , De Silva Sena , Bartley Devin , Cowx Ian G.
Published: February 2011

Inland fisheries are a vital component in the livelihoods and food security of people throughout the world, as well as contributing huge recreational and economic benefits. These valuable assets are jeopardized by lack of research-based understanding of the impacts of fisheries on inland ecosystems, and similarly the impact of human activities associated with inland waters on fisheries and aquatic biodiversity. To explore this topic, an international workshop was organized in order to examine strategies to incorporate fisheries into ecosystem approaches for management of inland waters. To achieve this goal, a new research agenda is needed that focuses on: quantifying the ecosystem services provided by fresh waters; quantifying the economic, social and nutritional benefits of inland fisheries; improving assessments designed to evaluate fisheries exploitation potential; and examining feedbacks between fisheries, ecosystem productivity and aquatic biodiversity. Accomplishing these objectives will require merging natural and social science approaches to address coupled social–ecological system dynamics.