bluuebunny/crossref_metadata_2025 huggingface dataset:
Do adsorbed drugs onto P-glycoprotein influence its efflux capability?
Authors: Ferreira Ricardo J. , Ferreira Maria-José U. , dos Santos Daniel J. V. A.
Published: July 2015

Drug adsorption to the protein–water and lipid–water interfaces influences the P-glycoprotein efflux capability.
Investigation of NH3 and NH4+ adsorbed on ZSM-5 zeolites by near and middle infrared spectroscopy
Authors: Takeuchi Masato , Tsukamoto Tatsuya , Kondo Atsushi , Matsuoka Masaya
Published: July 2015

NH4+ formed by NH3 adsorption on the H+ sites of ZSM-5 zeolite as well as molecularly adsorbed NH3 were simultaneously observed by near-infrared (NIR) spectroscopy. Furthermore, the formation of uniform NH3 clusters within the cavities of Na+-type and siliceous ZSM-5 were also observed.
Tuning of intramolecular charge transfer properties and charge distributions in ferrocene-appended catechol derivatives by chemical substitution
Authors: Tahara Keishiro , Akehi Shogo , Akita Tetsuhiro , Katao Shohei , Kikuchi Jun-ichi , Tokunaga Ken
Published: July 2015

The electronic interactions between an organometallic center and a non-innocent framework were tuned by chemical substitution.
Star-shaped PHB–PLA block copolymers: immortal polymerization with dinuclear indium catalysts
Authors: Yu I. , Ebrahimi T. , Hatzikiriakos S. G. , Mehrkhodavandi P.
Published: July 2015

The first example of a one-component precursor to star-shaped polyesters, and its utilization in the synthesis of previously unknown star-shaped poly(hydroxybutyrate)–poly(lactic acid) block copolymers, is reported.
Structural diversity of late transition metal complexes with flexible tetra-NHC ligands
Authors: Weiss Daniel T. , Altmann Philipp J. , Haslinger Stefan , Jandl Christian , Pöthig Alexander , Cokoja Mirza , Kühn Fritz E.
Published: July 2015

Silver complexes with flexible tetra-NHC ligands were used as transmetalation agent to access a series of d-block metal complexes.
Nutrient values and bioactivities of the extracts from three fern species in China: a comparative assessment
Authors: Qi Guoyuan , Yang Liuqing , Xiao Chunxia , Shi Jing , Mi Yashi , Liu Xuebo
Published: July 2015

Pteridium aquilinum, Osmunda cinnamomea Linn, and Athyrium multidentatum (Doll.) Ching are three fern species widely consumed as potherbs and traditional medicinal herbs in China.
Electrochemistry-based chemotaxonomy in plants using the voltammetry of microparticles methodology
Authors: Doménech-Carbó Antonio , Ibars Ana M. , Prieto-Mossi Josefa , Estrelles Elena , Scholz Fritz , Cebrián-Torrejón Gerardo , Martini Mariele
Published: July 2015

Characterization of vegetal taxa is achievedviacharacteristic voltammetric features displayed by leaf extracts.
Purification of avian biological material to refined keratin fibres
Authors: Pourjavaheri Firoozeh , Mohaddes Farzad , Bramwell Prue , Sherkat Frank , Shanks Robert A.
Published: July 2015

Keratin derived from chicken feather fibres (CFFs) has many potential applications that are constrained by the quality and pathogen content after purification treatment.
A facile synthesis and evaluation of new biomolecule-based coumarin–thiazoline hybrids as potent anti-tubercular agents with cytotoxicity, DNA cleavage and X-ray studies
Authors: Reddy Dinesh S. , Hosamani Kallappa M. , Devarajegowda Hirihalli C. , Kurjogi Mahantesh M.
Published: July 2015

A rapid and high yielding synthesis of coumarin–thiazoline hybrids as potent anti-tubercular agents, along with cytotoxicity, DNA cleavage and X-ray studies, is described.
One-step facile synthesis of fluorescent gold nanoclusters for rapid bio-imaging of cancer cells and small animals
Authors: Zhang Wanjun , Ye Jing , Zhang Yuanyuan , Li Qiwei , Dong Xiawei , Jiang Hui , Wang Xuemei
Published: July 2015

Fluorescent bio-imaging has become a major topic of the modern biomedical research field.
Transfer of SABRE-derived hyperpolarization to spin-1/2 heteronuclei
Authors: Pravdivtsev Andrey N. , Yurkovskaya Alexandra V. , Zimmermann Herbert , Vieth Hans-Martin , Ivanov Konstantin L.
Published: July 2015

Spin mixing at level anti-crossings (lacs) enables transfer of SABRE-derived spin polarization to spin-1/2 hetero-nuclei.
Unconventional seed-mediated growth of ultrathin Au nanowires in aqueous solution
Authors: Li Bo , Jiang Beibei , Tang Haillong , Lin Zhiqun
Published: July 2015

By adding a trace amount of hydrophobic molecules to conventional Au growth solution, CTAB-capped ultrathin Au nanowires were crafted.
Facile access to versatile hydrogels via interface-directed frontal polymerization derived from the magnetocaloric effect
Authors: Yu Chao , Wang Cai-Feng , Chen Su
Published: July 2015

An interface-directed synthetic pathway is employed to offer a tractable preparation of versatile hydrogels in minutes. The resultant hydrogels show pH, thermal, electrically and chemically responsive shape changes as well as adjustable self-healing capacity.
Design, synthesis and characterization of a new blue phosphorescent Ir complex
Authors: Yao Chuang , Li Jingxian , Wang Jinshan , Xu Xinjun , Liu Ronghua , Li Lidong
Published: July 2015

An efficient phosphorescent dye was developed by grafting a typically used phosphor to a functional group with an alkyl chain to suppress the phase aggregation.
Electrodynamics of planar Archimedean spiral resonator
Authors: Maleeva N. , Averkin A. , Abramov N. N. , Fistul M. V. , Karpov A. , Zhuravel A. P. , Ustinov A. V.
Published: July 2015

We present a theoretical and experimental study of electrodynamics of a planar spiral superconducting resonator of a finite length. The resonator is made in the form of a monofilar Archimedean spiral. By making use of a general model of inhomogeneous alternating current flowing along the resonator and specific boundary conditions on the surface of the strip, we obtain analytically the frequencies fn of resonances which can be excited in such system. We also calculate corresponding inhomogeneous RF current distributions ψn(r), where r is the coordinate across a spiral. We show that the resonant frequencies and current distributions are well described by simple relationships fn=f1n and ψn(r)≃ sin[πn(r/Re)2], where n=1,2... and Re is the external radius of the spiral. Our analysis of electrodynamic properties of spiral resonators' is in good agreement with direct numerical simulations and measurements made using specifically designed magnetic probe and laser scanning microscope.
Effects of feedstock availability on the negative ion behavior in a C4F8 inductively coupled plasma
Authors: Zhao Shu-Xia , Gao Fei , Wang Ya-Ping , Wang You-Nian , Bogaerts Annemie
Published: July 2015

In this paper, the negative ion behavior in a C4F8 inductively coupled plasma (ICP) is investigated using a hybrid model. The model predicts a non-monotonic variation of the total negative ion density with power at low pressure (10–30 mTorr), and this trend agrees well with experiments that were carried out in many fluorocarbon (fc) ICP sources, like C2F6, CHF3, and C4F8. This behavior is explained by the availability of feedstock C4F8 gas as a source of the negative ions, as well as by the presence of low energy electrons due to vibrational excitation at low power. The maximum of the negative ion density shifts to low power values upon decreasing pressure, because of the more pronounced depletion of C4F8 molecules, and at high pressure (∼50 mTorr), the anion density continuously increases with power, which is similar to fc CCP sources. Furthermore, the negative ion composition is identified in this paper. Our work demonstrates that for a clear understanding of the negative ion behavior in radio frequency C4F8 plasma sources, one needs to take into account many factors, like the attachment characteristics, the anion composition, the spatial profiles, and the reactor configuration. Finally, a detailed comparison of our simulation results with experiments is conducted.
The laser micro-machining system for diamond anvil cell experiments and general precision machining applications at the High Pressure Collaborative Access Team
Authors: Hrubiak Rostislav , Sinogeikin Stanislav , Rod Eric , Shen Guoyin
Published: July 2015

We have designed and constructed a new system for micro-machining parts and sample assemblies used for diamond anvil cells and general user operations at the High Pressure Collaborative Access Team, sector 16 of the Advanced Photon Source. The new micro-machining system uses a pulsed laser of 400 ps pulse duration, ablating various materials without thermal melting, thus leaving a clean edge. With optics designed for a tight focus, the system can machine holes any size larger than 3 μm in diameter. Unlike a standard electrical discharge machining drill, the new laser system allows micro-machining of non-conductive materials such as: amorphous boron and silicon carbide gaskets, diamond, oxides, and other materials including organic materials such as polyimide films (i.e., Kapton). An important feature of the new system is the use of gas-tight or gas-flow environmental chambers which allow the laser micro-machining to be done in a controlled (e.g., inert gas) atmosphere to prevent oxidation and other chemical reactions in air sensitive materials. The gas-tight workpiece enclosure is also useful for machining materials with known health risks (e.g., beryllium). Specialized control software with a graphical interface enables micro-machining of custom 2D and 3D shapes. The laser-machining system was designed in a Class 1 laser enclosure, i.e., it includes laser safety interlocks and computer controls and allows for routine operation. Though initially designed mainly for machining of the diamond anvil cell gaskets, the laser-machining system has since found many other micro-machining applications, several of which are presented here.
Focusing polycapillary to reduce parasitic scattering for inelastic x-ray measurements at high pressure
Authors: Chow P. , Xiao Y. M. , Rod E. , Bai L. G. , Shen G. Y. , Sinogeikin S. , Gao N. , Ding Y. , Mao H.-K.
Published: July 2015

The double-differential scattering cross-section for the inelastic scattering of x-ray photons from electrons is typically orders of magnitude smaller than that of elastic scattering. With samples 10-100 μm size in a diamond anvil cell at high pressure, the inelastic x-ray scattering signals from samples are obscured by scattering from the cell gasket and diamonds. One major experimental challenge is to measure a clean inelastic signal from the sample in a diamond anvil cell. Among the many strategies for doing this, we have used a focusing polycapillary as a post-sample optic, which allows essentially only scattered photons within its input field of view to be refocused and transmitted to the backscattering energy analyzer of the spectrometer. We describe the modified inelastic x-ray spectrometer and its alignment. With a focused incident beam which matches the sample size and the field of view of polycapillary, at relatively large scattering angles, the polycapillary effectively reduces parasitic scattering from the diamond anvil cell gasket and diamonds. Raw data collected from the helium exciton measured by x-ray inelastic scattering at high pressure using the polycapillary method are compared with those using conventional post-sample slit collimation.
Raman spectroscopy measurement of bilayer graphene's twist angle to boron nitride
Authors: Cheng Bin , Wang Peng , Pan Cheng , Miao Tengfei , Wu Yong , Taniguchi T. , Watanabe K. , Lau C. N. , Bockrath M.
Published: July 2015

When graphene is placed on hexagonal boron nitride with a twist angle, new properties develop due to the resulting moiré superlattice. Here, we report a method using Raman spectroscopy to make rapid, non-destructive measurements of the twist angle between bilayer graphene and hexagonal boron nitride. The lattice orientation is determined by using flakes with both bilayer and monolayer regions, and using the known Raman signature for the monolayer to measure the twist angle of the entire flake. The widths of the second order Raman peaks are found to vary linearly in the superlattice period and are used to determine the twist angle. The results are confirmed by using transport measurements to infer the superlattice period by the charge density required to reach the secondary resistance peaks. Small twist angles are also found to produce a significant modification of the first order Raman G band peak.
Fingerprints of energy dissipation for exothermic surface chemical reactions: O2 on Pd(100)
Authors: Bukas Vanessa J. , Mitra Shubhrajyoti , Meyer Jörg , Reuter Karsten
Published: July 2015

We present first-principles calculations of the sticking coefficient of O2 at Pd(100) to assess the effect of phononic energy dissipation on this kinetic parameter. For this, we augment dynamical simulations on six-dimensional potential energy surfaces (PESs) representing the molecular degrees of freedom with various effective accounts of surface mobility. In comparison to the prevalent frozen-surface approach, energy dissipation is found to qualitatively affect the calculated sticking curves. At the level of a generalized Langevin oscillator model, we achieve good agreement with experimental data. The agreement is similarly reached for PESs based on two different semi-local density-functional theory functionals. This robustness of the simulated sticking curve does not extend to the underlying adsorption mechanism, which is predominantly directly dissociative for one functional or molecularly trapped for the other. Completely different adsorption mechanisms therewith lead to rather similar sticking curves that agree equally well with the experimental data. This highlights the danger of the prevalent practice to extract corresponding mechanistic details from simple fingerprints of measured sticking data for such exothermic surface reactions.
The influence of hydrogen on the chemical, mechanical, optical/electronic, and electrical transport properties of amorphous hydrogenated boron carbide
Authors: Nordell Bradley J. , Karki Sudarshan , Nguyen Thuong D. , Rulis Paul , Caruso A. N. , Purohit Sudhaunshu S. , Li Han , King Sean W. , Dutta Dhanadeep , Gidley David , Lanford William A. , Paquette Michelle M.
Published: July 2015

Because of its high electrical resistivity, low dielectric constant (κ), high thermal neutron capture cross section, and robust chemical, thermal, and mechanical properties, amorphous hydrogenated boron carbide (a-BxC:Hy) has garnered interest as a material for low-κ dielectric and solid-state neutron detection applications. Herein, we investigate the relationships between chemical structure (atomic concentration B, C, H, and O), physical/mechanical properties (density, porosity, hardness, and Young's modulus), electronic structure [band gap, Urbach energy (EU), and Tauc parameter (B1/2)], optical/dielectric properties (frequency-dependent dielectric constant), and electrical transport properties (resistivity and leakage current) through the analysis of a large series of a-BxC:Hy thin films grown by plasma-enhanced chemical vapor deposition from ortho-carborane. The resulting films exhibit a wide range of properties including H concentration from 10% to 45%, density from 0.9 to 2.3 g/cm3, Young's modulus from 10 to 340 GPa, band gap from 1.7 to 3.8 eV, Urbach energy from 0.1 to 0.7 eV, dielectric constant from 3.1 to 7.6, and electrical resistivity from 1010 to 1015 Ω cm. Hydrogen concentration is found to correlate directly with thin-film density, and both are used to map and explain the other material properties. Hardness and Young's modulus exhibit a direct power law relationship with density above ∼1.3 g/cm3 (or below ∼35% H), below which they plateau, providing evidence for a rigidity percolation threshold. An increase in band gap and decrease in dielectric constant with increasing H concentration are explained by a decrease in network connectivity as well as mass/electron density. An increase in disorder, as measured by the parameters EU and B1/2, with increasing H concentration is explained by the release of strain in the network and associated decrease in structural disorder. All of these correlations in a-BxC:Hy are found to be very similar to those observed in amorphous hydrogenated silicon (a-Si:H), which suggests parallels between the influence of hydrogenation on their material properties and possible avenues for optimization. Finally, an increase in electrical resistivity with increasing H at <35 at. % H concentration is explained, not by disorder as in a-Si:H, but rather by a lower rate of hopping associated with a lower density of sites, assuming a variable range hopping mechanism interpreted in the framework of percolation theory.
Laboratory x-ray microscopy on high brilliance sources equipped with waveguides
Authors: Fella C. , Balles A. , Zabler S. , Hanke R. , Tjeung R. , Nguyen S. , Pelliccia D.
Published: July 2015

We report on the experimental realization of propagation-based x-ray microscopy with laboratory sources equipped with waveguides. We discuss about the experimental setup, the fabrication steps, and the characterization procedures of the waveguide optics. We demonstrate that the system enables high resolution attenuation imaging of poorly absorbing biological specimens. Furthermore, we report the successful realization of propagation-based phase contrast x-ray microscopy, enabling quantitative thickness estimation in homogeneous objects. Advantages and major limitations of the experimental scheme are presented and discussed.
Order parameters and magnetocrystalline anisotropy of off-stoichiometric D22 Mn2.36Ga epitaxial films grown on MgO (001) and SrTiO3 (001)
Authors: Lee Hwachol , Sukegawa Hiroaki , Mitani Seiji , Hono Kazuhiro
Published: July 2015

We study the relationship between long range order parameters and the magnetocrystalline anisotropy of off-stoichiometric D022 Mn2.36Ga (MnGa) epitaxial films grown on MgO (001) and SrTiO3 (STO) (001) single crystalline substrates. MnGa films deposited on MgO (001) show rather large irregular variation in magnetization with increasing substrate temperature in spite of the improved long range order of total atomic sites. The specific site long range order of Mn-I site characterized in the [101] orientation revealed the fluctuation of the occupation fraction of two Mn atomic sites with elevated substrate temperature, which appears more relevant to the observed magnetization change than the long range order of the total atomic sites. In case of MnGa films grown on the lattice-matched STO (001), high long range order of the total atomic sites in spite of the existence of secondary phase represents that the lattice mismatch plays a crucial role in determining the atomic arrangement of Mn and Ga atoms in the off-stoichiometric compositional case of MnGa.
Fabrication and electrical properties of single wall carbon nanotube channel and graphene electrode based transistors arrays
Authors: Seo M. , Kim H. , Kim Y. H. , Na J. , Lee B. J. , Kim J. J. , Lee I. , Yun H. , McAllister K. , Kim K. S. , Jeong G. H. , Kim G. T. , Lee S. W.
Published: July 2015

A transistor structure composed of an individual single-walled carbon nanotube (SWNT) channel with a graphene electrode was demonstrated. The integrated arrays of transistor devices were prepared by transferring patterned graphene electrode patterns on top of the aligned SWNT along one direction. Both single and multi layer graphene were used for the electrode materials; typical p-type transistor and Schottky diode behavior were observed, respectively. Based on our fabrication method and device performances, several issues are suggested and discussed to improve the device reliability and finally to realize all carbon based future electronic systems.
Inverted, semitransparent small molecule photovoltaic cells
Authors: Xiao Xin , Lee Kyusang , Forrest Stephen R.
Published: July 2015

We demonstrate semitransparent small molecule organic photovoltaic (OPV) cells based on inverted mixed and hybrid planar-mixed heterojunction (PM-HJ) structures comprised of a neat acceptor layer located beneath the donor/acceptor mixed region. The fill factor increases from 0.53 ± 0.01 for the mixed HJ to 0.58 ± 0.01 for the PM-HJ due to reduced series resistance, whereas the internal quantum efficiency increases from an average of 75% to 85% between the wavelengths of λ = 450 nm and 550 nm. The inverted, semitransparent PM-HJ cell achieves a power conversion efficiency of PCE = 3.9% ± 0.2% under simulated AM1.5G illumination at one sun intensity with an average optical transmission of T¯ = 51% ± 2% across the visible spectrum, corresponding to > 10% improvement compared with the mixed HJ cell. We also demonstrate an inverted semitransparent tandem cell incorporating two PM-HJ sub-cells with different absorption spectra. The tandem cell achieves a PCE = 5.3% ± 0.3% under simulated AM1.5G at one sun intensity with T¯ = 31% ± 1% across the visible. Almost identical efficiencies are obtained for tandem cells illuminated via either the cathode or anode surfaces.
Rhenium-phthalocyanine molecular nanojunction with high magnetic anisotropy and high spin filtering efficiency
Authors: Li J. , Hu J. , Wang H. , Wu R. Q.
Published: July 2015

Using the density functional and non-equilibrium Green's function approaches, we studied the magnetic anisotropy and spin-filtering properties of various transition metal-Phthalocyanine molecular junctions across two Au electrodes. Our important finding is that the Au-RePc-Au junction has both large spin filtering efficiency (>80%) and large magnetic anisotropy energy, which makes it suitable for device applications. To provide insights for the further experimental work, we discussed the correlation between the transport property, magnetic anisotropy, and wave function features of the RePc molecule, and we also illustrated the possibility of controlling its magnetic state.
Controlling magnetic domain wall motion in the creep regime in He+-irradiated CoFeB/MgO films with perpendicular anisotropy
Authors: Herrera Diez L. , García-Sánchez F. , Adam J.-P. , Devolder T. , Eimer S. , El Hadri M. S. , Lamperti A. , Mantovan R. , Ocker B. , Ravelosona D.
Published: July 2015

This study presents the effective tuning of perpendicular magnetic anisotropy in CoFeB/MgO thin films by He+ ion irradiation and its effect on domain wall motion in a low field regime. Magnetic anisotropy and saturation magnetisation are found to decrease as a function of the irradiation dose which can be related to the observed irradiation-induced changes in stoichiometry at the CoFeB/MgO interface. These changes in the magnetic intrinsic properties of the film are reflected in the domain wall dynamics at low magnetic fields (H) where irradiation is found to induce a significant decrease in domain wall velocity (v). For all irradiation doses, domain wall velocities at low fields are well described by a creep law, where Ln(v) vs. H−1∕4 behaves linearly, up to a maximum field H*, which has been considered as an approximation to the value of the depinning field Hdep. In turn, H* ≈ Hdep is seen to increase as a function of the irradiation dose, indicating an irradiation-induced extension of the creep regime of domain wall motion.
One-dimensional edge state of Bi thin film grown on Si(111)
Authors: Kawakami Naoya , Lin Chun-Liang , Kawai Maki , Arafune Ryuichi , Takagi Noriaki
Published: July 2015

The geometric and electronic structures of the Bi thin film grown on Si(111) were investigated by using scanning tunneling microscopy and spectroscopy. We have found two types of edges, one of which hosts an electronic state localized one-dimensionally. We also revealed the energy dispersion of the localized edge state from the evolution of quasiparticle interference patterns as a function of energy. These spectroscopic findings well reproduce those acquired for the cleaved surface of the bulk Bi crystal [I. K. Drozdov et al., Nat. Phys. 10, 664 (2014)]. The present results indicate that the deposited Bi film provides a tractable stage for further scrutiny of the one-dimensional edge state.
Monolithically integrated self-rolled-up microtube-based vertical coupler for three-dimensional photonic integration
Authors: Yu Xin , Arbabi Ehsan , Goddard Lynford L. , Li Xiuling , Chen Xiaogang
Published: July 2015

We demonstrate a self-rolled-up microtube-based vertical photonic coupler monolithically integrated on top of a ridge waveguide to achieve three-dimensional (3D) photonic integration. The fabrication process is fully compatible with standard planar silicon processing technology. Strong light coupling between the vertical coupler and the ridge waveguide was observed experimentally, which may provide an alternative route for 3D heterogeneous photonic integration. The highest extinction ratio observed in the transmission spectrum passing through the ridge waveguide was 23 dB.
Phase transformation and magnetic properties of rapidly solidified Mn-Al-C alloys modified with Zr
Authors: Geng Yunlong , Lucis Michael J. , Rasmussen Pamela , Shield Jeffrey E.
Published: July 2015

Mn54−xAl43C3Zrx (x = 1, 3) alloys were prepared by rapid solidification followed by heat treatment to produce the ferromagnetic τ phase. The substitution of Zr for Mn in the structure resulted in an increase of the saturation magnetization (Ms) compared to that of Mn54Al43C3. While the highest Ms (128 ± 1 emu/g) was obtained in Mn53Al43C3Zr1, the coercivity was also improved to 1.62 kOe, compared to 1.25 kOe for Mn54Al43C3. To further improve the coercivity through grain refinement, additional C (1%, 3%, 5%, and 7%) was added to Mn53Al43C3Zr1. An increase in the coercivity was observed due to a decrease of grain size and the formation of nonmagnetic phases, which reduced the magnetostatic interactions between the τ-phase grains. However, excess C reduced the saturation magnetization due to the formation of the other non-ferromagnetic phases, including ε, γ2, and β phases.
Insight into the mechanism of end-of-day far-red light (EODFR)-induced shade avoidance responses in Arabidopsis thaliana
Authors: Mizuno Takeshi , Oka Haruka , Yoshimura Fumi , Ishida Kai , Yamashino Takafumi
Published: July 2015

Shade avoidance responses are changes in plant architecture to reduce the part of a body that is in the shade in natural habitats. The most common warning signal that induces shade avoidance responses is reduction of red/far-red light ratio perceived by phytochromes. A pair of basic helix–loop–helix transcription factors, named PHYTOCHROME-INTERACTING FACTOR 4 (PIF4) and PIF5, is crucially involved in the shade avoidance-induced hypocotyl elongation in Arabidopsis thaliana. It has been recently reported that PIF7 also plays a role in this event. Here, we examined the involvement of these PIFs in end-of-day far-red light (EODFR) responses under light and dark cycle conditions. It was shown that PIF7 played a predominant role in the EODFR-dependent hypocotyl elongation. We propose the mechanism by which PIF7 together with PIF4 and PIF5 coordinately transcribes a set of downstream genes to promote elongation of hypocotyls in response to the EODFR treatment.
The formation of ordered nanoclusters controls cadherin anchoring to actin and cell–cell contact fluidity
Authors: Strale Pierre-Olivier , Duchesne Laurence , Peyret Grégoire , Montel Lorraine , Nguyen Thao , Png Evelyn , Tampé Robert , Troyanovsky Sergey , Hénon Sylvie , Ladoux Benoit , Mège René-Marc
Published: July 2015

Oligomerization of cadherins could provide the stability to ensure tissue cohesion. Cadherins mediate cell–cell adhesion by forming trans-interactions. They form cis-interactions whose role could be essential to stabilize intercellular junctions by shifting cadherin clusters from a fluid to an ordered phase. However, no evidence has been provided so far for cadherin oligomerization in cellulo and for its impact on cell–cell contact stability. Visualizing single cadherins within cell membrane at a nanometric resolution, we show that E-cadherins arrange in ordered clusters, providing the first demonstration of the existence of oligomeric cadherins at cell–cell contacts. Studying the consequences of the disruption of the cis-interface, we show that it is not essential for adherens junction formation. Its disruption, however, increased the mobility of junctional E-cadherin. This destabilization strongly affected E-cadherin anchoring to actin and cell–cell rearrangement during collective cell migration, indicating that the formation of oligomeric clusters controls the anchoring of cadherin to actin and cell–cell contact fluidity.
The influence of self-esteem and role stress on job performance in hotel businesses
Authors: Akgunduz Yilmaz
Published: July 2015

Purpose

– The main purpose of this study is to explore the influence of self-esteem and role stress on job performance in the hotel businesses. Moreover, the research aims to discover which role stress factors, i.e. role ambiguity, role conflict and role overload, have the most detrimental effect on an employee’s role stress in the hotel businesses.

Design/methodology/approach

– To achieve the above aim, four sets of hypotheses were proposed: the first looked into the effect of role stress, which consists of role ambiguity, role conflict and role overload on job performance, and the second focused on the effect of employees’ self-esteem on job performance. A questionnaire was used and participants were drawn from 227 hotel employees in Kusadasi, Turkey. To empirically test these hypotheses, structural equation modeling was implemented.

Findings

– The outcome of the study indicated three patterns: role ambiguity and role conflict are negatively associated with job performance; role overload and self-esteem are positively associated with job performance; and role ambiguity creates more role stress than role conflict or overload.

Practical implications

– The research findings suggest that some practical methodology should be introduced to improve employees’ job performance and diminish role stress. For instance, hotel managers should decrease role ambiguity and conflict, employ personnel with high self-esteem and prioritize reducing role overload rather than reducing role ambiguity or role conflict.

Originality/value

– The research findings suggest that both role stress and self-esteem are important factors influencing job performance in hotel management. This paper aims to identify some important steps to increase job performance. Thus, our study should prove to be of great value to those in hotel management.
Old wine in a new bottle: money demand causality for 10 Asian countries
Authors: Ajmi Ahdi Noomen , Apergis Nicholas , Montasser Ghassen El
Published: July 2015

Purpose

– The purpose of this paper is to estimate causality properties between real money demand and a number of determinants, i.e., real output, the lending rate and the real exchange rate, across ten Asian economies.

Design/methodology/approach

– The study makes use of the causality methodology of Emirmahmutoglu and Kose (2011) over the period 1990-2012.

Findings

– The results document both bidirectional and unidirectional causality between monetary aggregates (M1 and M2) and their determinants for different country groups.

Research limitations/implications

– The empirical findings exemplify the role of the demand for money as a policy tool and can provide useful policy guidelines to the Asian central banks in their quest for price stability.

Originality/value

– This paper for the first time estimates causality properties between real money demand and a number of determinants, across ten Asian economies that have not used before in the literature. In addition, it employs the innovative methodology of Emirmahmutoglu and Kose (2011). The advantages of this approach are: it overcomes the problem of pre-testing needs to determine the order of integration, the lag orders on the autoregressive coefficients as well as the exogenous variable coefficients are mixed for all the cross-section units of the sample, and it is based on the approach of Meta-analysis which is capable of obtaining common results, combining those provided by a number of independent studies which test the same hypothesis.
The SME perspective on motives and success factors in cross-border mergers
Authors: Ratajczak-Mrozek Milena
Published: July 2015

Purpose

– The purpose of this paper is to address two research questions. First: what causes an small and medium enterprises (SME) to engage in a merger with a multinational group and thereby change its relationships and to start functioning in a hierarchical structure which may be viewed as being the integration of a weaker entity by a stronger and bigger one? And second: what causes the successful continuation of a cross-border merger project from the perspective of an SME?

Design/methodology/approach

– The concept of the network position is adopted to undertake a longitudinal study of an IT company from Poland.

Findings

– From the perspective of the SME, its own perceived important network position resulting from the resources it possesses, the ability to decide how they are utilised, as well as relationships strongly supported by trust and a good atmosphere are key motives and success factors for the merger.

Originality/value

– By adapting the IMP research perspective and the concept of network position to the analysis of mergers the additional aspects of the merger process which are usually not raised in relevant traditional mergers and acquisitions literature are revealed. A merger is not just the sourcing of resources, but also interdependencies and taking joint decisions with regard to them; not just economic aspects, but also social aspects of relationships (trust and atmosphere); not just the sharing of resources between merged entities, but also the constant influence of other relationships and interactions on these resources.
Construction of meanings in business relationships and networks
Authors: La Rocca Antonella , Snehota Ivan , Trabattoni Carlotta
Published: July 2015

Purpose

– The purpose of this paper is to address an issue related to the role of interaction processes in the development of customer-supplier relationships in business markets.

Design/methodology/approach

– Focusing on the role of cognition in interaction behaviours in business relationships, the authors examine two research streams that offer perspectives on interaction processes akin to the IMP – the socio-cognitive perspective and the practice-based approach to markets and marketing.

Findings

– The two research streams analysed contribute to understanding the link between cognition and interaction behaviours by pointing to the construction of meanings as an important factor in interaction behaviours and indicating storytelling as a tool to construct meanings among the actors.

Originality/value

– This paper is among the few studies that focus the attention on communication processes in business relationships and networks.
Mutualism effectiveness of a fungal endophyte in an annual grass is impaired by ozone
Authors: Ueno Andrea C. , Gundel Pedro E. , Omacini Marina , Ghersa Claudio M. , Bush Lowell P. , Martínez‐Ghersa María Alejandra
Published: July 2015

Ozone is an increasing tropospheric contaminant of climate change. Exposure to ozone may affect the symbiotic relationship between plants and beneficial microorganisms. In particular, the herbivore resistance mechanism conferred by fungal endophytes (defensive mutualism) may be affected, as any of the ozone‐triggered effects (such as elicitation of defence mechanisms against biotrophic fungi or oxidative stress in the apoplastic space) may target the symbiont.

Symbiotic and non‐symbiotic Lolium multiflorum plants were exposed to ozone for two consecutive days (2 h per day), after which half were infested with 10 aphids (Rhopalosiphum padi). We measured variables related to performance of plants, the endophyte symbiont (alkaloids) and the herbivores.

Aphid populations were smaller on symbiotic plants than in non‐symbiotic plants in low‐ozone conditions. However, this difference disappeared in exposed plants to high‐ozone conditions. Under low‐ozone conditions, structure of aphid populations on endophyte‐symbiotic plants was characterized by a low number of nymphs and a high number of adults. This pattern was not observed with high‐ozone exposure. Level of fungal alkaloids (lolines) was not affected by either ozone or herbivory.

Results indicate that ozone impairs the grass‐endophyte symbiosis without affecting production of alkaloids generally linked with aphids' response to endophyte presence. Since neither plant biomass nor alkaloid level were affected by ozone, other ozone‐mediated mechanisms at molecular or biochemical level may underlie plant‐herbivore interaction mediated by fungal endophytes. Thus, the mechanism behind this effect must be determined in future experiments.
Novel candidate genes for impaired nephron development in a rat model with inherited nephron deficit and albuminuria
Authors: Herlan Laura , Schulz Angela , Schulte Leonard , Schulz Herbert , Hübner Norbert , Kreutz Reinhold
Published: July 2015

Defects in nephrogenesis can have detrimental effects on cardiovascular and renal health in adult life. This is confirmed by observations in the Munich Wistar Frömter (MWF) rat that exhibits a congenital nephron deficit and renal failure with age. Here, we performed genome‐wide transcriptome analysis in embryonic kidneys to identify candidate genes for the reduced nephron number in MWF. We compared MWF rats at embryonic day (E)15.5 with stage‐matched spontaneously hypertensive rats (SHR) at E16. Microarray analysis revealed 311 transcripts representing 253 known genes with differential expression between MWF and SHR (fold change > +1.5 or < −1.5, respectively). Genes located on rat chromosome (RNO) 6 were of special interest because RNO6 carries genetic loci previously linked to the nephron deficit and renal damage in MWF. Differentially expressed genes located on RNO6 were further investigated by Real‐time PCR including the late‐stage of fetal kidney development, i.e. E19.0/E19.5, and week 4 of postnatal life when nephrogenesis is completed. Seven genes including Abcg5, Ab1‐233, Efcab11, Fntb, Gpx2, Lrrn3, and Rtn1 were assigned on RNO6 and their differential expression was confirmed. Thus, we identified several genes that may act as crucial players in nephron development and are responsible for the nephron deficit in the MWF model.
Antimicrobial stewardship in Australian emergency departments
Authors: Welch Susan
Published: July 2015

Objective

The present study aims to determine and describe the involvement of Australian EDs in antimicrobial stewardship (AMS) and the role of Emergency Medicine Pharmacists (EMPs).

Methods

A Surveymonkey® questionnaire was devised, piloted and distributed to all members of the Society of Hospital Pharmacists of Australia Committee of Specialty Practice EM via the online discussion forum and email distribution list.

Results

There were 41 respondents, 35 (85%) of which had an EMP at their hospital. Of respondents, 30 (73%) were EMP, nine were involved in ED and wanted to contribute to the survey and two were neither. Thirty‐four (83%) had a hospital AMS programme. All other questions had 29 respondents. Twenty‐three of 29 (79%) had an AMS committee, and 14/23 (61%) had an ED representation. Twenty‐eight of 29 (97%) had a restricted antimicrobial policy. Twenty‐one of 29 (72%) had a specialist AMS pharmacist, and 12/21 (57%) were involved in the ED. Eleven of 29 (37%) had ED‐specific antimicrobial guidelines. A variety of electronic AMS support is available in EDs. EDs had access to a hospital antibiogram (6) and used it to inform AMS. Point prevalence surveys often involved the ED. EMPs were involved with antimicrobial education via ward rounds (6) and didactic sessions (7), guideline development (4), and monitoring of ED antimicrobial prescribing, 21/29 (72%). Multiple ways of controlling ED antimicrobials were used including: providing a limited range of after‐hours antimicrobials, predetermined trauma packs, review of ED stock and follow up of restricted antimicrobials. Fourteen of 29 (48%) had conducted ED antimicrobial drug use evaluations.

Conclusion

The ED can be a focus for AMS and is at many sites surveyed. The EMP can provide an important role in this programme.
Establishing the role of detoxifying enzymes in field‐evolved resistance to various insecticides in the brown planthopper (Nilaparvata lugens) in South India
Authors: Malathi Vijayakumar Maheshwari , Jalali Sushil K. , Gowda Dandinashivara K. Sidde , Mohan Muthugounder , Venkatesan Thiruvengadam
Published: July 2015

The brown planthopper (BPH), Nilaparvata lugens (Stål), is one of the major pests of rice throughout Asia. Extensive use of insecticides for suppressing N. lugens has resulted in the development of insecticide resistance leading to frequent control failures in the field. The aim of the present study was to evaluate resistance in the field populations of N. lugens from major rice growing states of South India to various insecticides. We also determined the activity of detoxifying enzymes (esterases [ESTs], glutathione S‐transferases [GSTs], and mixed‐function oxidases [MFOs]). Moderate levels of resistance were detected in the field populations to acephate, thiamethoxam and buprofezin (resistance factors 1.05–20.92 fold, 4.52–14.99 fold, and 1.00–18.09 fold, respectively) as compared with susceptible strain while there were low levels of resistance to imidacloprid (resistance factor 1.23–6.70 fold) and complete sensitivity to etofenoprox (resistance factor 1.05–1.66 fold). EST activities in the field populations were 1.06 to 3.09 times higher than the susceptible strain while for GST and MFO the ratios varied from 1.29 to 3.41 and 1.03 to 1.76, respectively. The EST activity was found to be correlated to acephate resistance (r = 0.999, P ≥ 0.001). The high selection pressure of organophosphate, neonicotinoid, and insect growth regulator (IGR) in the field is likely to be contributing for resistance in BPH to multiple insecticides, leading to control failures. The results obtained will be beneficial to IPM recommendations for the use of effective insecticides against BPH.
Abdominal pain symptoms are associated with anxiety and depression in young children
Authors: von Gontard Alexander , Moritz Anne‐Michaela , Thome‐Granz Sigrid , Equit Monika
Published: July 2015

Aim

Abdominal pain symptoms and incontinence are common in childhood. The aim of this study was to analyse abdominal pain symptoms and their associations with incontinence and symptoms of anxiety and depression in young children.

Methods

We examined 1130 children during the school entry check‐up (mean age 6.2 years) and 951 participated in the study. Parents completed a questionnaire contained 11 items regarding Rome‐III functional gastrointestinal disorders (FGIDs) and incontinence and 14 items from the anxious/depressed scale of the Child Behavior Checklist (CBCL).

Results

Of the 951 children (55.6% boys) we recruited, 30.1% had experienced abdominal pain symptoms in the past two months and 14% had complained of them at least once a week. In addition, 2.6% had irritable bowel syndrome, 11.3% had childhood functional abdominal pain, 2.4% were affected by faecal incontinence, 2.1% were affected by daytime urinary incontinence, and 5.5% were affected by nocturnal enuresis. One in ten (10.6%) had symptoms of anxiety and depression, and these were significantly higher in the children with FGIDs, particularly if they were also incontinent.

Conclusion

Nearly a third of the children (30.1%) had abdominal pain symptoms, and FGIDs were associated with significantly higher symptoms of anxiety and depression, especially if children were also incontinent.
Small MultiPiles: Piling Time to Explore Temporal Patterns in Dynamic Networks
Authors: Bach B. , Henry‐Riche N. , Dwyer T. , Madhyastha T. , Fekete J‐D. , Grabowski T.
Published: July 2015

We introduce MultiPiles, a visualization to explore time‐series of dense, weighted networks. MultiPiles is based on the physical analogy of piling adjacency matrices, each one representing a single temporal snapshot. Common interfaces for visualizing dynamic networks use techniques such as: flipping/animation; small multiples; or summary views in isolation. Our proposed ‘piling’ metaphor presents a hybrid of these techniques, leveraging each one's advantages, as well as offering the ability to scale to networks with hundreds of temporal snapshots. While the MultiPiles technique is applicable to many domains, our prototype was initially designed to help neuroscientists investigate changes in brain connectivity networks over several hundred snapshots. The piling metaphor and associated interaction and visual encodings allowed neuroscientists to explore their data, prior to a statistical analysis. They detected high‐level temporal patterns in individual networks and this helped them to formulate and reject several hypotheses.
Visual Assessment of Alleged Plagiarism Cases
Authors: Riehmann P. , Potthast M. , Stein B. , Froehlich B.
Published: July 2015

We developed a visual analysis tool to support the verification, assessment, and presentation of alleged cases of plagiarism. The analysis of a suspicious document typically results in a compilation of categorized “finding spots”. The categorization reveals the way in which the suspicious text fragment was created from the source, e.g. by obfuscation, translation, or by shake and paste. We provide a three‐level approach for exploring the finding spots in context. The overview shows the relationship of the entire suspicious document to the set of source documents. A glyph‐based view reveals the structural and textual differences and similarities of a set of finding spots and their corresponding source text fragments. For further analysis and editing of the finding spot's assessment, the actual text fragments can be embedded side‐by‐side in the diffline view. The different views are tied together by versatile navigation and selection operations. Our expert reviewers confirm that our tool provides a significant improvement over existing static visualizations for assessing plagiarism cases.
Exploring Traffic Dynamics in Urban Environments Using Vector‐Valued Functions
Authors: Poco Jorge , Doraiswamy Harish , Vo Huy. T. , Comba João L. D. , Freire Juliana , Silva Cláudio. T.
Published: July 2015

The traffic infrastructure greatly impacts the quality of life in urban environments. To optimize this infrastructure, engineers and decision makers need to explore traffic data. In doing so, they face two important challenges: the sparseness of speed sensors that cover only a limited number of road segments, and the complexity of traffic patterns they need to analyze. In this paper we take a first step at addressing these challenges. We use New York City (NYC) taxi trips as sensors to capture traffic information. While taxis provide substantial coverage of the city, the data captured about taxi trips contain neither the location of taxis at frequent intervals nor their routes. We propose an efficient traffic model to derive speed and direction information from these data, and show that it provides reliable estimates. Using these estimates, we define a time‐varying vector‐valued function on a directed graph representing the road network, and adapt techniques used for vector fields to visualize the traffic dynamics. We demonstrate the utility of our technique in several case studies that reveal interesting mobility patterns in NYC's traffic. These patterns were validated by experts from NYC's Department of Transportation and the NYC Taxi & Limousine Commission, who also provided interesting insights into these results.