bluuebunny/crossref_metadata_2025 huggingface dataset:
Near-infrared electrochemiluminescence from Au25(SC2H4Ph)18+ clusters co-reacted with tri-n-propylamine
Authors: Hesari Mahdi , Workentin Mark S. , Ding Zhifeng
Published: June 2014

The wavelength and intensity of electrochemiluminescence in the Au25+ clusters/tri-n-propylamine (TPrA) co-reactant system can be tuned by varying the TPrA concentration and applied potential.
Piezoelectric-based apparatus for strain tuning
Authors: Hicks Clifford W. , Barber Mark E. , Edkins Stephen D. , Brodsky Daniel O. , Mackenzie Andrew P.
Published: June 2014

We report the design and construction of piezoelectric-based apparatus for applying continuously tuneable compressive and tensile strains to test samples. It can be used across a wide temperature range, including cryogenic temperatures. The achievable strain is large, so far up to 0.23% at cryogenic temperatures. The apparatus is compact and compatible with a wide variety of experimental probes. In addition, we present a method for mounting high-aspect-ratio samples in order to achieve high strain homogeneity.
Experimental study of rarefied gas flow near sudden contraction junction of a tube
Authors: Varade Vijay , Agrawal Amit , Pradeep A. M.
Published: June 2014

An experimental study of nearly isothermal rarefied gas flow near the sudden contraction junction of a tube is presented in this paper. The measurements are performed with nitrogen gas flowing at low pressures in conventional tubes with sudden contraction area ratios of 1.48, 3.74, 12.43, and 64. The flow is dynamically similar to gas flow in a microchannel as the Knudsen number (0.0001 < Kn < 0.032) falls in the slip flow regime. The Reynolds number in the smaller section (Res) ranges between 0.2 and 837. The static pressure measurements are analyzed to understand the flow behavior. The static pressure variation along the wall and uniform radial pressure profile near the junction indicates absence of flow separation and vena contracta. The static pressure variation in both the tubes approaches the pressure variation as that of an isolated straight tube at a certain critical Knudsen number for a given area ratio. The velocity field is obtained through a momentum balance and using the flow measurements. The effect of larger momentum diffusivity and slip at the wall, restricts any deviation in velocity profile from its parabolic nature at the junction and suppresses flow separation and vena contracta. The larger inertia force at the sudden contraction junction causes larger acceleration of the flow near the junction in the smaller tube as compared to that of the straight tube. The larger pressure drop in the sudden contraction is a result of the extent of flow compression and additional acceleration near the junction in the smaller tube as compared to the straight tube. This paper reports a set of new results that are expected to help in improving understanding of gaseous slip flows.
Total skin electron beam therapy using an inclinable couch on motorized table and a compensating filter
Authors: Fuse H. , Suzuki K. , Shida K. , Mori Y. , Takahashi H. , Kobayashi D. , Seki M. , Isobe T. , Okumura T. , Sakae T. , Sakurai H.
Published: June 2014

Total skin electron beam is a specialized technique that involves irradiating the entire skin from the skin surface to only a few millimetres in depth. In the Stanford technique, the patient is in a standing position and six different directional positions are used during treatment. Our technique uses large electron beams in six directions with an inclinable couch on motorized table and a compensating filter was also used to spread the electron beam and move its intensity peak. Dose uniformity measurements were performed using Gafchromic films which indicated that the surface dose was 2.04 ± 0.05 Gy. This technique can ensure the dose reproducibility because the patient is fixed in place using an inclinable couch on a motorized table.
Desorption of oxygen from alloyed Ag/Pt(111)
Authors: Jankowski Maciej , Wormeester Herbert , Zandvliet Harold J. W. , Poelsema Bene
Published: June 2014

We have investigated the interaction of oxygen with the Ag/Pt(111) surface alloy by thermal desorption spectroscopy (TDS). The surface alloy was formed during the deposition of sub-monolayer amounts of silver on Pt(111) at 800 K and subsequent cooling to 300 K. The low-temperature phase of the surface alloy is composed of nanometer-sized silver rich stripes, embedded within platinum-rich domains, which were characterized with spot profile analysis low energy electron diffraction. The TDS measurements show that oxygen adsorption is blocked on Ag sites: the saturation coverage of oxygen decreases with increasing Ag coverage. Also, the activation energy for desorption (Edes) decreases with Ag coverage. The analysis of the desorption spectra from clean Pt(111) shows a linear decay of Edes with oxygen coverage, which indicates repulsive interactions between the adsorbed oxygen atoms. In contrast, adsorption on alloyed Ag/Pt(111) leads to an attractive interaction between adsorbed oxygen atoms.
Toroidal mode number estimation of the edge-localized modes using the KSTAR 3-D electron cyclotron emission imaging system
Authors: Lee J. , Yun G. S. , Lee J. E. , Kim M. , Choi M. J. , Lee W. , Park H. K. , Domier C. W. , Luhmann N. C. , Sabbagh S. A. , Park Y. S. , Lee S. G. , Bak J. G.
Published: June 2014

A new and more accurate technique is presented for determining the toroidal mode number n of edge-localized modes (ELMs) using two independent electron cyclotron emission imaging (ECEI) systems in the Korea Superconducting Tokamak Advanced Research (KSTAR) device. The technique involves the measurement of the poloidal spacing between adjacent ELM filaments, and of the pitch angle α* of filaments at the plasma outboard midplane. Equilibrium reconstruction verifies that α* is nearly constant and thus well-defined at the midplane edge. Estimates of n obtained using two ECEI systems agree well with n measured by the conventional technique employing an array of Mirnov coils.
Effective-medium model of wire metamaterials in the problems of radiative heat transfer
Authors: Mirmoosa M. S. , Rüting F. , Nefedov I. S. , Simovski C. R.
Published: June 2014

In the present work, we check the applicability of the effective medium model (EMM) to the problems of radiative heat transfer (RHT) through so-called wire metamaterials (WMMs)—composites comprising parallel arrays of metal nanowires. It is explained why this problem is so important for the development of prospective thermophotovoltaic (TPV) systems. Previous studies of the applicability of EMM for WMMs were targeted by the imaging applications of WMMs. The analogous study referring to the transfer of radiative heat is a separate problem that deserves extended investigations. We show that WMMs with practically realizable design parameters transmit the radiative heat as effectively homogeneous media. Existing EMM is an adequate tool for qualitative prediction of the magnitude of transferred radiative heat and of its effective frequency band.
Analytical and numerical study of resolution criteria in large-eddy simulation
Authors: Fauconnier D. , Dick E.
Published: June 2014

The present work investigates the influence of the primary filter resolution on various turbulence statistics and the representation of vortical structures in Large-Eddy Simulation (LES) of homogeneous isotropic turbulent flow. The resolution effects are investigated both analytically and numerically for an ideal LES solution with negligible modeling and numerical errors, and as such equivalent to filtered direct numerical simulation data. The Taylor-Green vortex is considered for the numerical investigation. Several resolution criteria, found in the literature, which prescribe the filter width requirements for LES, are investigated and their effect on various turbulent statistics is evaluated analytically. Further, the resolution effect on vortical structures is evaluated numerically using the Taylor-Green vortex. Finally, an optimal resolution for LES is derived via a multi-objective optimization, maximizing the resolved fractions of specifically chosen turbulent quantities while minimizing the computational overhead in comparison with a reference simulation. The optimum resolution criterion was found to be \documentclass[12pt]{minimal}\begin{document}$\kappa _e\lambda \approx 0.27\mathrm{Re}_\lambda ^{0.36}$\end{document}κeλ≈0.27 Re λ0.36. However, a more practical quasi-optimal criterion κeλ ≈ π is proposed resulting in an acceptable trade-off between accuracy and computational overhead.
Structural heterogeneities at the origin of acoustic and transport anomalies in glycerol glass-former
Authors: Busselez Rémi , Pezeril Thomas , Gusev Vitalyi E.
Published: June 2014

By means of large scale molecular dynamics simulations, we explore mesoscopic properties of prototypical glycerol glass-former above and below the glass transition. The model used, in excellent agreement with various experimental techniques, permits to carefully study the structure and the vibrational dynamics. We find that a medium range order is present in glycerol glass-former and arises from hydrogen bond network extension. The characteristic size of the structural heterogeneities is related to the anomalous properties of acoustic vibrations (Rayleigh scattering, “mode softening,” and Boson Peak) in the glassy state. Finally the characteristic size of these heterogeneities, nearly constant in temperature, is also connected to the cross-over between structural relaxation and diffusion in liquid glycerol.
Structural and magnetotransport properties of ultrathin Co/ZnO and Co/ZnAlO films
Authors: Quan Zhi-Yong , Zhang Xian-Peng , Liu Wei , Albargi H. B. , Gehring G. A. , Xu Xiao-Hong
Published: June 2014

We report the structural and magnetotransport properties of ultrathin superparamagnetic Co/ZnO and Co/ZnAlO films deposited by sequentially sputtering Co layers and semiconductor layers. The films consisting of Co nanodots embedded in an amorphous semiconductor matrix exhibit large room temperature tunneling magnetoresistance with a maximum value of over 7%. The single-layer-nanodot structures gradually develop in the films with thicknesses below 8 nm, where tunneling processes existing only between nanodots that lie in a plane are realized. The tunneling magnetoresistance ratio at room temperature is as high as 5% although the thickness of the Co/ZnAlO film is as thin as 3.2 nm. These single-layer-nanodot films having high tunneling magnetoresistance ratios and superparamagnetic behavior can be used in transparent nano-granular in gap sensors.
Accurate and reproducible detection of proteins in water using an extended-gate type organic transistor biosensor
Authors: Minamiki Tsukuru , Minami Tsuyoshi , Kurita Ryoji , Niwa Osamu , Wakida Shin-ichi , Fukuda Kenjiro , Kumaki Daisuke , Tokito Shizuo
Published: June 2014

In this Letter, we describe an accurate antibody detection method using a fabricated extended-gate type organic field-effect-transistor (OFET), which can be operated at below 3 V. The protein-sensing portion of the designed device is the gate electrode functionalized with streptavidin. Streptavidin possesses high molecular recognition ability for biotin, which specifically allows for the detection of biotinylated proteins. Here, we attempted to detect biotinylated immunoglobulin G (IgG) and observed a shift of threshold voltage of the OFET upon the addition of the antibody in an aqueous solution with a competing bovine serum albumin interferent. The detection limit for the biotinylated IgG was 8 nM, which indicates the potential utility of the designed device in healthcare applications.
Bandwidth broadening and asymmetric softening of collective spin waves in magnonic crystals
Authors: Montoncello F. , Giovannini L.
Published: June 2014

We investigate the dependence on the applied field of the frequency/wavevector dispersion relations of collective spin waves in arrays of dots, close to a magnetic transition. In particular, we focus on the low frequency “soft” modes in three different cases: end modes in the transition between two different saturated states in ellipses, fundamental mode in the saturated-to-vortex transition in disks, and gyrotropic mode in the vortex-to-saturated transition in disks. Noteworthy, the spin waves with nonzero Bloch wavevector along the direction of the applied field happen to soften earlier than spin waves with a Bloch wavevector along different directions, and this feature is responsible for an asymmetric broadening of the bandwidth along the different lattice directions. This is particularly useful in magnonic/spin-logic device research, if different binary digits are associated to modes with the same cell function but different propagation directions.
Surface passivation of tellurium-doped GaAs nanowires by GaP: Effect on electrical conduction
Authors: Darbandi A. , Salehzadeh O. , Kuyanov P. , LaPierre R. R. , Watkins S. P.
Published: June 2014

We report on the surface passivation of Au-assisted Te-doped GaAs nanowires (NWs) grown by metalorganic vapor phase epitaxy. The electrical properties of individual free standing NWs were assessed using a tungsten nano-probe inside a scanning electron microscope. The diameter independent apparent resistivity of both strained and relaxed passivated NWs suggests the unpinning of the Fermi level and reduction of sidewalls surface states density. Similar current-voltage properties were observed for partially axially relaxed GaAs/GaP NWs. This indicates a negligible contribution of misfit dislocations in the charge transport properties of the NWs. Low temperature micro-photoluminescence (μ-PL) measurements were also carried out for both uncapped and passivated GaAs NWs. The improvement of the integrated (μ-PL) intensity for GaAs/GaP NWs further confirms the effect of passivation.
Effect of time derivative of contact area on dynamic friction
Authors: Arakawa Kazuo
Published: June 2014

This study investigated dynamic friction during oblique impact of a golf ball by evaluating the ball's angular velocity, contact force, and the contact area between the ball and target. The effect of the contact area on the angular velocities was evaluated, and the results indicated that the contact area plays an important role in dynamic friction. In this study, the dynamic friction force F was given by F = μN + μη dA/dt, where μ is the coefficient of friction, N is the contact force, dA/dt is the time derivative of the contact area A, and η is a coefficient associated with the contact area.
The study of temperature dependent strain in Ge epilayer with SiGe/Ge buffer layer on Si substrate with different thickness
Authors: Wu Po-Hung , Huang Ying-Sheng , Hsu Hung-Pin , Li Cheng , Huang Shi-Hao , Tiong Kwong-Kau
Published: June 2014

Temperature dependent near band edge transitions in Ge epilayer on Si substrate with different thickness were studied by using photoreflectance (PR) and piezoreflectance (PzR) measurements. The identification of conduction to light-hole (LH) band and conduction to heavy-hole (HH) band transitions originated from the strain induced valence band splitting results from tensile strain have been achieved by comparing the relative intensities of PR and PzR spectra. The strain induced energy splitting between LH and HH can be reduced with a thinner substrate and can be accounted by the mismatch of thermal expansion coefficients between the Si substrate and Ge epilayer. We also studied temperature dependent energy splitting between LH and HH through theoretical calculations. The comparison of energy splitting between experiments and theoretical calculations were made and discussed.
Multi-mode electro-mechanical vibrations of a microtubule: In silico demonstration of electric pulse moving along a microtubule
Authors: Havelka Daniel , Cifra Michal , Kučera Ondřej
Published: June 2014

Microtubules are known to be involved in intracellular signaling. Here, we show in silico that electrically polar collective vibration modes of microtubules form electric oscillating potential which is quasi-periodic both in space and in time. While single mode microtubule vibration excites an electric field with spatially stationary local minima and maxima of the electric field, the multimode excitation causes the formation of an electric pulse and many transient local electric field minima. The biophysical mechanism we describe lends support to the view that microtubules may comprise a substrate for ultra-fast electrical signaling in neurons or other living cells.
Precision stress localization during mechanical harvesting of vertically oriented semiconductor micro- and nanostructure arrays
Authors: Ombaba M. M. , Jayaraman L. V. , Islam M. S.
Published: June 2014

A facile protocol of channeling the applied force onto the roots of 1-dimensional (1-d) semiconductor arrays during their mechanical transfer from their mother substrate is presented. This is achieved by fully encasing them in thermally processable matrices with high moduli and impact strength. This approach significantly differs from other complimentary methods as it ensures that the shearing force applied during their transfer is precisely localized at their roots rather than along their full length. The structures remain heterogeneously embedded in the matrix upon transfer, with retention of their pitch, lengths, and integrity. The process is solventless, recycles polystyrene, is rugged, and can potentially be used to transfer a variety of 1-D structures with disregard of their aspect ratio, pitch, and dimensions. We show that millions of micropillars over a large area can be harvested with little sophistication using a hotplate as the only required equipment practically as well as using finite element simulation studies. The protocol is henceforth ripe for high throughput manufacturing.
Magneto-transport properties of oriented Mn2CoAl films sputtered on thermally oxidized Si substrates
Authors: Xu G. Z. , Du Y. , Zhang X. M. , Zhang H. G. , Liu E. K. , Wang W. H. , Wu G. H.
Published: June 2014

Spin gapless semiconductors are interesting family of materials by embracing both magnetism and semiconducting due to their unique band structure. Its potential application in future spintronics requires realization in thin film form. In this Letter, we report fabrication and transport properties of spin gapless Mn2CoAl films prepared on thermally oxidized Si substrates by magnetron sputtering deposition. The films deposited at 673 K are well oriented to (001) direction and display a uniform-crystalline surface. Magnetotransport measurements on the oriented films reveal a semiconducting-like resistivity, small anomalous Hall conductivity, and linear magnetoresistance representative of the transport signatures of spin gapless semiconductors. The magnetic properties of the films have also been investigated and compared to that of bulk Mn2CoAl, showing small discrepancy induced by the composition deviation.
Cooperative pulses for pseudo-pure state preparation
Authors: Wei Daxiu , Chang Yan , Glaser Steffen J. , Yang Xiaodong
Published: June 2014

Using an extended version of the optimal-control-based gradient ascent pulse engineering algorithm, cooperative (COOP) pulses are designed for multi-scan experiments to prepare pseudo-pure states in quantum computation. COOP pulses can cancel undesired signal contributions, complementing and generalizing phase cycles. They also provide more flexibility and, in particular, eliminate the need to select specific individual target states and achieve the fidelity of theoretical limit by flexibly choosing appropriate number of scans and duration of pulses. The COOP approach is experimentally demonstrated for three-qubit and four-qubit systems.
Nondestructive quantitative mapping of impurities and point defects in thin films: Ga and VZn in ZnO:Ga
Authors: Look David C. , Leedy Kevin D. , Agresta Donald L.
Published: June 2014

Ga-doped ZnO (GZO) films grown by pulsed-laser deposition on quartz and other lattice-mismatched substrates can routinely attain resistivities of 2 × 10−4 Ω·cm and thus compete with Sn-doped In2O3 (ITO) in large-area transparent-electrode applications. Nondestructive, high-resolution (1-mm) maps of thickness d, concentration n, and mobility μ on such films can be obtained automatically from commercial spectroscopic ellipsometers. From n and μ, degenerate-electron scattering theory yields donor ND and acceptor NA concentrations at each point. Finally, ND and NA can be identified as [Ga] and [VZn], respectively, demonstrating high-density mapping of impurities and point defects in a semiconductor thin film.
Mechanisms of electromechanical coupling in strain based scanning probe microscopy
Authors: Chen Qian Nataly , Ou Yun , Ma Feiyue , Li Jiangyu
Published: June 2014

Electromechanical coupling is ubiquitous in nature and underpins the functionality of materials and systems as diverse as ferroelectric and multiferroic materials, electrochemical devices, and biological systems, and strain-based scanning probe microscopy (s-SPM) techniques have emerged as a powerful tool in characterizing and manipulating electromechanical coupling at the nanoscale. Uncovering underlying mechanisms of electromechanical coupling in these diverse materials and systems, however, is a difficult outstanding problem, and questions and confusions arise from recent experiment observations of electromechanical coupling and its apparent polarity switching in some unexpected materials. We propose a series of s-SPM experiments to identify different microscopic mechanisms underpinning electromechanical coupling and demonstrate their feasibility using three representative materials. By employing a combination of spectroscopic studies and different modes of s-SPM, we show that it is possible to distinguish electromechanical coupling arising from spontaneous polarization, induced dipole moment, and ionic Vegard strain, and this offers a clear guidance on using s-SPM to study a wide variety of functional materials and systems.
Quantifying selection in immune receptor repertoires
Authors: Elhanati Yuval , Murugan Anand , Callan Curtis G. , Mora Thierry , Walczak Aleksandra M.
Published: June 2014

Significance

The immune system defends against pathogens through a diverse population of T cells that display different antigen recognition surface receptor proteins. Receptor diversity is produced by an initial random gene recombination process followed by selection for a desirable range of peptide binding. Although recombination is well-understood, selection has not been quantitatively characterized. By combining high-throughput sequencing data with modeling, we quantify the selection pressure that shapes functional repertoires. Selection is found to vary little between individuals or between naive and memory repertoires. It reinforces the biases of the recombination process, meaning that sequences more likely to be produced are also more likely to pass selection. The model accounts for public sequences shared between individuals as resulting from pure chance.
Unripe Rubus coreanus Miquel suppresses migration and invasion of human prostate cancer cells by reducing matrix metalloproteinase expression
Authors: Kim Yesl , Lee Seung Min , Kim Jung-Hyun
Published: June 2014

Rubus coreanus Miquel (RCM) is used to promote prostate health and has been shown to have anti-oxidant and anti-carcinogenic activities. However, the effects and mechanisms of RCM on prostate cancer metastasis remain unclear. PC-3 and DU 145 cells were treated with ethanol or water extract of unripe or ripe RCM and examined for cell invasion, migration, and matrix metalloproteinases (MMPs) activity and expression. Phosphoinositide 3-kinase (PI3K) and Akt activities were examined. Unripe RCM extracts exerted significant inhibitory effects on cell migration, invasion, and MMPs activities. A significant reduction in MMPs activities by unripe RCM ethanol extract treatment (UE) was associated with reduction of MMPs expression and induction of tissue inhibitors of metalloproteinases (TIMPs) expression. Furthermore, PI3K/Akt activity was diminished by UE treatment. In this study, we demonstrated that UE decreased metastatic potential of prostate cancer cells by reducing MMPs expression through the suppression of PI3K/Akt phosphorylation, thereby decreasing MMP activity and enhancing TIMPs expression.
Multiplanar breast kinematics during different exercise modalities
Authors: Risius Deborah , Milligan Alexandra , Mills Chris , Scurr Joanna
Published: June 2014

Multiplanar breast movement reduction is crucial to increasing physical activity participation amongst women. To date, research has focused on breast movement during running, but until breast movement is understood during different exercise modalities, the breast support requirements for specific activities are unknown. To understand breast support requirements during different exercise modalities, this study aimed to determine multiplanar breast kinematics during running, jumping and agility tasks. Sixteen 32D participants had markers attached to their right nipple and torso. Relative multiplanar breast displacement was calculated during bare‐breasted treadmill running (10 kph), maximum countermovement jumping and an agility t‐test. Exercise modality influenced the magnitude and direction of breast displacement, velocity and acceleration (p <. 05). Jumping produced greater vertical breast displacement (.09 m) but less mediolateral breast displacement (.05 m) than running or the agility task, but agility tasks produced the highest multiplanar breast velocities and acceleration. Breast movement during jumping was predominantly in the vertical direction, whereas the agility task produced a greater percentage of mediolateral breast acceleration than running or jumping. Exercise modality impacted upon the magnitude and distribution of bare‐breasted multiplanar breast kinematics in this homogenous 32D cohort. Therefore, to reduce breast movement in women of a 32D bra size, manufacturers may wish to design sport‐specific products, with greater vertical support for exercise modalities incorporating jumping and greater mediolateral support for agility tasks.
A role for nuclear envelope–bridging complexes in homology-directed repair
Authors: Swartz Rebecca K. , Rodriguez Elisa C. , King Megan C.
Published: June 2014

Unless efficiently and faithfully repaired, DNA double-strand breaks (DSBs) cause genome instability. We implicate a Schizosaccharomyces pombe nuclear envelope–spanning linker of nucleoskeleton and cytoskeleton (LINC) complex, composed of the Sad1/Unc84 protein Sad1 and Klarsicht/Anc1/SYNE1 homology protein Kms1, in the repair of DSBs. An induced DSB associates with Sad1 and Kms1 in S/G2 phases of the cell cycle, connecting the DSB to cytoplasmic microtubules. DSB resection to generate single-stranded DNA and the ATR kinase drive the formation of Sad1 foci in response to DNA damage. Depolymerization of microtubules or loss of Kms1 leads to an increase in the number and size of DSB-induced Sad1 foci. Further, Kms1 and the cytoplasmic microtubule regulator Mto1 promote the repair of an induced DSB by gene conversion, a type of homology-directed repair. kms1 genetically interacts with a number of genes involved in homology-directed repair; these same gene products appear to attenuate the formation or promote resolution of DSB-induced Sad1 foci. We suggest that the connection of DSBs with the cytoskeleton through the LINC complex may serve as an input to repair mechanism choice and efficiency.
An aspartyl cathepsin,CTH3, is essential for proprotein processing during secretory granule maturation inTetrahymena thermophila
Authors: Kumar Santosh , Briguglio Joseph S. , Turkewitz Aaron P.
Published: June 2014

In Tetrahymena thermophila, peptides secreted via dense-core granules, called mucocysts, are generated by proprotein processing. We used expression profiling to identify candidate processing enzymes, which localized as cyan fluorescent protein fusions to mucocysts. Of note, the aspartyl cathepsin Cth3p plays a key role in mucocyst-based secretion, since knockdown of this gene blocked proteolytic maturation of the entire set of mucocyst proproteins and dramatically reduced mucocyst accumulation. The activity of Cth3p was eliminated by mutation of two predicted active-site mutations, and overexpression of the wild-type gene, but not the catalytic-site mutant, partially rescued a Mendelian mutant defective in mucocyst proprotein processing. Our results provide the first direct evidence for the role of proprotein processing in this system. Of interest, both localization and the CTH3 disruption phenotype suggest that the enzyme provides non–mucocyst-related functions. Phylogenetic analysis of the T. thermophila cathepsins, combined with prior work on the role of sortilin receptors in mucocyst biogenesis, suggests that repurposing of lysosomal enzymes was an important step in the evolution of secretory granules in ciliates.
Mechanochemical regulation of oscillatory follicle cell dynamics in the developing Drosophila egg chamber
Authors: Koride Sarita , He Li , Xiong Li-Ping , Lan Ganhui , Montell Denise J. , Sun Sean X.
Published: June 2014

During tissue elongation from stage 9 to stage 10 in Drosophila oogenesis, the egg chamber increases in length by ∼1.7-fold while increasing in volume by eightfold. During these stages, spontaneous oscillations in the contraction of cell basal surfaces develop in a subset of follicle cells. This patterned activity is required for elongation of the egg chamber; however, the mechanisms generating the spatiotemporal pattern have been unclear. Here we use a combination of quantitative modeling and experimental perturbation to show that mechanochemical interactions are sufficient to generate oscillations of myosin contractile activity in the observed spatiotemporal pattern. We propose that follicle cells in the epithelial layer contract against pressure in the expanding egg chamber. As tension in the epithelial layer increases, Rho kinase signaling activates myosin assembly and contraction. The activation process is cooperative, leading to a limit cycle in the myosin dynamics. Our model produces asynchronous oscillations in follicle cell area and myosin content, consistent with experimental observations. In addition, we test the prediction that removal of the basal lamina will increase the average oscillation period. The model demonstrates that in principle, mechanochemical interactions are sufficient to drive patterning and morphogenesis, independent of patterned gene expression.
Constraints on the gas masses of low-z damped Lyman α systems
Authors: Mazumdar Parichay , Kanekar Nissim , Prochaska J. Xavier
Published: June 2014

We report a deep search for redshifted H i 21 cm emission from three damped and sub-damped Lyman α absorbers (DLAs) at z ≈ 0.1 with the Green Bank Telescope (GBT). No evidence for a redshifted H i 21 cm emission signal was obtained in the GBT spectra of two absorbers, with the data on the third rendered unusable by terrestrial interference. The non-detections of H i 21 cm emission yield strong constraints on the H i masses of the associated galaxies, MH i < 2.3 × 109 × (Δ V/100)1/2 M⊙ for the sub-DLA at z = 0.0830 towards J1553+3548 and MH i < 2.7 × 109 × (Δ V/100)1/2 M⊙ for the DLA at z = 0.0963 towards J1619+3342, where ΔV is the H i 21 cm line width, in km s−1. This continues the trend of low H i masses found in all low-z DLAs and sub-DLAs that have been searched for redshifted H i 21 cm emission. Low-redshift absorbers with relatively low H i column densities, ≲ few × 1020 cm−2, thus do not typically arise in massive gas-rich galaxies.
Ceftaroline in Combination With Trimethoprim-Sulfamethoxazole for Salvage Therapy of Methicillin-Resistant Staphylococcus aureus Bacteremia and Endocarditis
Authors: Fabre Valeria , Ferrada Marcela , Buckel Whitney R. , Avdic Edina , Cosgrove Sara E.
Published: June 2014

No clinical trials have investigated the use of ceftaroline fosamil for salvage therapy of methicillin-resistant Staphylococcus aureus bacteremia and endocarditis. We report data on 29 patients who received ceftaroline ± another antimicrobial for this indication. Ninety percent of patients had microbiologic cure and 31% had treatment success with a median follow-up of 6 months.
Near-infrared colors of asteroid 2012 DA14 at its closest approach to Earth: Observations with the Nishiharima Infrared Camera (NIC)
Authors: Takahashi Jun , Urakawa Seitaro , Terai Tsuyoshi , Hanayama Hidekazu , Arai Akira , Honda Satoshi , Takagi Yuhei , Itoh Yoichi , Zenno Takahiro , Ishiguro Masateru
Published: June 2014

We present the results of our JHKs photometry of asteroid 2012 DA14 at its closest approach to Earth on 2013 February 15. Possible spectral changes associated with resurfacing by planetary encounters are of great interest. The Earth flyby of 2012 DA14 provided a rare opportunity to investigate this effect. Our observations were conducted using the Nishiharima Infrared Camera (NIC) attached to the 2.0 m Nayuta telescope at the Nishi-Harima Astronomical Observatory. Despite the extraordinarily fast sky motion of up to near 50″ s−1, the telescope successfully tracked the asteroid. The NIC achievement of three-band simultaneous observations allowed us to reliably deduce the colors of this fast-moving object. The derived near-infrared relative reflectances are flat, which is consistent with the classification of the asteroid as L-type. The J − H and H − Ks colors at 0.5–1 hr after the closest approach are compared with those observed by de León (2013, A&A, 555, L2) at ∼ 10 hr after the closest time. We did not detect color changes significantly exceeding the photometric errors, which are ∼ 0.1 mag. This project has demonstrated the potential of the NIC as a three-band simultaneous imager, especially for observations of rapidly time-variable phenomena.
(R,S)-Ketamine Metabolites (R,S)-norketamine and (2S,6S)-hydroxynorketamine Increase the Mammalian Target of Rapamycin Function
Authors: Paul Rajib K. , Singh Nagendra S. , Khadeer Mohammed , Moaddel Ruin , Sanghvi Mitesh , Green Carol E. , O’Loughlin Kathleen , Torjman Marc C. , Bernier Michel , Wainer Irving W.
Published: June 2014

Background:

Subanesthetic doses of (R,S)-ketamine are used in the treatment of neuropathic pain and depression. In the rat, the antidepressant effects of (R,S)-ketamine are associated with increased activity and function of mammalian target of rapamycin (mTOR); however, (R,S)-ketamine is extensively metabolized and the contribution of its metabolites to increased mTOR signaling is unknown.

Methods:

Rats (n = 3 per time point) were given (R,S)-ketamine, (R,S)-norketamine, and (2S,6S)-hydroxynorketamine and their effect on the mTOR pathway determined after 20, 30, and 60 min. PC-12 pheochromocytoma cells (n = 3 per experiment) were treated with escalating concentrations of each compound and the impact on the mTOR pathway was determined.

Results:

The phosphorylation of mTOR and its downstream targets was significantly increased in rat prefrontal cortex tissue by more than ~2.5-, ~25-, and ~2-fold, respectively, in response to a 60-min postadministration of (R,S)-ketamine, (R,S)-norketamine, and (2S,6S)-hydroxynorketamine (P < 0.05, ANOVA analysis). In PC-12 pheochromocytoma cells, the test compounds activated the mTOR pathway in a concentration-dependent manner, which resulted in a significantly higher expression of serine racemase with ~2-fold increases at 0.05 nM (2S,6S)-hydroxynorketamine, 10 nM (R,S)-norketamine, and 1,000 nM (R,S)-ketamine. The potency of the effect reflected antagonistic activity of the test compounds at the α7-nicotinic acetylcholine receptor.

Conclusions:

The data demonstrate that (R,S)-norketamine and (2S,6S)-hydroxynorketamine have potent pharmacological activity both in vitro and in vivo and contribute to the molecular effects produced by subanesthetic doses of (R,S)-ketamine. The results suggest that the determination of the mechanisms underlying the antidepressant and analgesic effects of (R,S)-ketamine requires a full study of the parent compound and its metabolites.
Immune defence strategies of generalist and specialist insect herbivores
Authors: Barthel Andrea , Kopka Isabell , Vogel Heiko , Zipfel Peter , Heckel David G. , Groot Astrid T.
Published: June 2014

Ecological immunology examines the adaptive responses of animals to pathogens in relation to other environmental factors and explores the consequences of trade-offs between investment in immune function and other life-history traits. Among species of herbivorous insects, diet breadth may vary greatly, with generalists consuming a wide variety of plant families and specialists restricted to a few species. Generalists may thus be exposed to a wider range of pathogens exerting stronger selection on the innate immune system. To examine whether this produces an increase in the robustness of the immune response, we compared larvae of the generalist herbivoreHeliothis virescensand the specialistHeliothis subflexachallenged by entomopathogenic and non-pathogenic bacteria.Heliothis virescenslarvae showed lower mortality, a lower number of recoverable bacteria, lower proliferation of haemocytes and higher phagocytic activity. These results indicate a higher tolerance to entomopathogenic bacteria by the generalist, which is associated with a more efficient cell-mediated immune response by mechanisms that differ between these closely related species. Our findings provide novel insights into the consequences of diet breadth and related environmental factors, which may be significant in further studies to understand the ecological forces and investment trade-offs that shape the evolution of innate immunity.
Lactobacillus apinorum sp. nov., Lactobacillus mellifer sp. nov., Lactobacillus mellis sp. nov., Lactobacillus melliventris sp. nov., Lactobacillus kimbladii sp. nov., Lactobacillus helsingborgensis sp. nov. and Lactobacillus kullabergensis sp. nov., isolated from the honey stomach of the honeybee Apis mellifera
Authors: Olofsson Tobias C. , Alsterfjord Magnus , Nilson Bo , Butler Èile , Vásquez Alejandra
Published: June 2014

We previously discovered a symbiotic lactic acid bacterial (LAB) microbiota in the honey stomach of the honeybee Apis mellifera. The microbiota was composed of several phylotypes of

Bifidobacterium

and

Lactobacillus

. 16S rRNA gene sequence analyses and phenotypic and genetic characteristics revealed that the phylotypes isolated represent seven novel species. One grouped with

Lactobacillus kunkeei

and the others belong to the

Lactobacillus buchneri

and

Lactobacillus delbrueckii

subgroups of

Lactobacillus

. We propose the names Lactobacillus apinorum sp. nov., Lactobacillus mellifer sp. nov., Lactobacillus mellis sp. nov., Lactobacillus melliventris sp. nov., Lactobacillus kimbladii sp. nov., Lactobacillus helsingborgensis sp. nov. and Lactobacillus kullabergensis sp. nov. for these novel species, with the respective type strains being Fhon13NT ( = DSM 26257T = CCUG 63287T), Bin4NT ( = DSM 26254T = CCUG 63291T), Hon2NT ( = DSM 26255T = CCUG 63289T), Hma8NT ( = DSM 26256T = CCUG 63629T), Hma2NT ( = DSM 26263T = CCUG 63633T), Bma5NT ( = DSM 26265T = CCUG 63301T) and Biut2NT ( = DSM 26262T = CCUG 63631T).
Temperatibacter marinus gen. nov., sp. nov., a mesophilic bacterium isolated from surface seawater and description of Temperatibacteraceae fam. nov. in the class Alphaproteobacteria
Authors: Teramoto Maki , Nishijima Miyuki
Published: June 2014

A Gram-stain-negative, motile, mesophilic, aerobic, rod-shaped bacterium, strain 5-11T, was isolated from surface seawater at Muroto city, Kochi prefecture, Japan. The strain exhibited a narrow growth temperature range of 20–30 °C. Phylogenetic analyses based on 16S rRNA gene sequences showed that the strain fell within the order

Kordiimonadales

in the class

Alphaproteobacteria

and was related most closely to the genus

Kordiimonas

(up to 91.2 % similarity to the type strains of species of the genus) but branched deeply from species of

Kordiimonas

. The major fatty acids were iso-C17 : 1ω9c, iso-C15 : 0, and C16 : 1ω7c and/or iso-C15 : 0 2-OH. Ubiquinone-10 (Q-10) was detected as the sole isoprenoid quinone. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and one unidentified aminolipid. Although strains of

Kordiimonas

have been shown to contain unidentified glycolipids, they were not detected from strain 5-11T. The DNA G+C content of strain 5-11T was 44.3 mol%, a value that was lower than those of strains of

Kordiimonas

(50–58 mol%) and was relatively low for the members of the class

Alphaproteobacteria

. On the basis of phenotypic, genotypic and chemotaxonomic data, it is proposed that strain 5-11T represents a novel species of a new genus, Temperatibacter marinus gen. nov., sp. nov., within a new family Temperatibacteraceae fam. nov. The type strain of Temperatibacter marinus is 5-11T ( = NBRC 110045T = LMG 28278T).
Atopobium
deltae sp. nov., isolated from the blood of a patient with Fournier’s gangrene
Authors: Cools Piet , Oyaert Matthijs , Vaneechoutte Mario , De Laere Emmanuel , Vervaeke Steven
Published: June 2014

A Gram-stain-positive, obligately anaerobic, short rod, designated strain HHRM1715T, was isolated from the blood of a patient with Fournier’s gangrene, complicated by sepsis. On the basis of 16S rRNA gene sequence analysis, strain HHRM1715T was shown to belong to the genus

Atopobium

and was most closely related to

Atopobium minutum

(95 % similarity). The results of 16S rRNA-gene-based phylogenetic analysis, cellular fatty acid analysis and differential biochemical tests, showed that strain HHRM1715T represented a novel species of the genus

Atopobium

. We therefore describe Atopobium deltae sp. nov. with HHRM1715T ( = LMG 27987T = CCUG 65171T) as the type strain and propose an emended description of the genus

Atopobium

with regard to the DNA G+C content.
African financial development dynamics: big time convergence
Authors: A. Asongu Simplice
Published: June 2014

Purpose

– Assessment of African financial development dynamic convergences in money, credit, efficiency and size. The paper aims to discuss these issues.

Design/methodology/approach

– The empirical evidence is premised on 11 homogenous panels based on regions (Sub-Saharan and North Africa), income-levels (low, middle, lower-middle and upper-middle), legal-origins (English common-law and French civil-law) and religious dominations (Christianity and Islam). The paper examines convergence in financial intermediary dynamics of depth, efficiency, activity and size.

Findings

– Findings suggest that countries with small-sized financial intermediary depth, efficiency, activity and size are catching-up countries with large-sized financial intermediary depth, efficiency, activity and size, respectively. The paper also provide the speeds of convergence and time necessary to achieve a full (100 percent) convergence.

Practical implications

– The presence of strong links among African banking sectors may present little opportunity for portfolio diversification. The convergence patterns show positive steps toward regional integration. As a policy implication, African governments should not relent in structural and institutional reforms.

Originality/value

– It is the first critical assessment of convergence in financial intermediary development dynamics in the African continent.
Consumer perceptions and functional evaluations of cash desk types in the clothing retail context
Authors: Yildirim Kemal , Ayalp Nur , Guner Aktas Gozen , Lutfi Hidayetoglu M.
Published: June 2014

Purpose

– The purpose of this paper is to focus on assessing consumer perceptions and functional evaluations of store cash desks (Flat, L- and U-shaped) in the clothing retail context.

Design/methodology/approach

– To test the assumption that relationships exist between various types of cash desks and consumer perceptions and functional evaluations, a study was devised using digital pictures of three types of cash desks hypothetically located in a large store.

Findings

– Results based on semantic differential and functional items show that consumers expressed a more positive perception of flat than of L- or U-shaped cash desks. Men evaluated the store cash desks more positively than women overall. Managerial implications are discussed and directions for future research are proposed.

Originality/value

– This paper reveals a significant relationship between cash desk type and consumer perceptions and functional evaluations of cash desks. The results of the work suggest that retailers and designers may be able to easily make stores more attractive to consumers by installing flat cash desks.
Depositor discipline and the bank
'
s incentive to monitor
Authors: Ferguson Michael F. , Stevenson Bradley A.
Published: June 2014

Purpose

– The aim of this paper is to examine the question of the specialness of banks by addressing concerns raised in the recent studies and deriving policy implications for the future of banking. The specialness of banks has been well documented in the finance literature. More recent research, however, calls into question the special nature of banks.

Design/methodology/approach

– We use event study methodology to study 423 bank loan announcements from 1988 to 1996 and examine the returns relative to proxies for the bank
'
s monitoring incentives and skill using ordinary least squares (OLS) regressions.

Findings

– Our results indicate borrower abnormal announcement returns are positively related to proxies for the bank
'
s monitoring incentives and skill as measured by: the ratio of uninsured deposits to total loans; a risk-adjusted measure of recovered charge-offs; and the relative bank-to-borrower capital ratio.

Research limitations/implications

– The results reveal how the fragile nature of the bank
'
s structure improves the bank
'
s incentives to monitor borrowers.

Practical implications

– Our results can inform the current debates in the Fed and in Congress surrounding reapplying the Glass-Steagall Act and limiting the size of banks. We show that banks were special before the Gramm-Leach-Bliley Act and when fewer banks belonged to the too-big-to-fail category. This suggests that reregulating banks to re-establish their fragile nature will re-establish them as information-generating intermediaries instead of just transactional institutions.

Originality/value

– Our findings have not previously been documented but are broadly consistent with models developed by Calomiris and Kahn (1991) and especially Diamond and Rajan (2001).
Bank’s perspective on regulatory-driven changes to collateral management
Authors: Prorokowski Lukasz
Published: June 2014

Purpose

– The aim of this paper is to discuss the impact of regulatory-driven changes to the collateral management landscape, indicating operational and technological challenges faced by global investment banks while complying with the new regulatory framework. As it transpires, collateral management strategies need to be revised to find optimal solutions for the regulatory-shaped landscape. Furthermore, set against the regulatory background, this paper attempts to provide some insights into the future risks and shocks to collateral management.

Design/methodology/approach

– This paper recognizes the dearth of up-to-date studies on current issues with collateral management and overnight indexed swap (OIS) discounting. Therefore, to introduce new theoretical avenues, this paper is based on an exploratory, qualitative approach to analyse the regulatory-driven collateral management.

Findings

– The increased use of collateral, with a sharp focus on its quality, liquidity and eligibility for central clearing, requires a new approach to collateral management and discounting methods. At this point, banks (especially those with agency businesses) should develop an enterprise-wide view of collateral by having a central data repository, which allows access to information about the transactions conducted with all counterparties.

Originality/value

– Analysing the regulatory-driven (Basel III; Dodd-Frank; EMIR) changes to collateral management, this paper adopts banks’ perspectives on the new regulations in collateral management. The paper contributes to the widespread, albeit complex, discussion on how banks adapt to the rapidly changing environment in collateral management and risk operations.