bluuebunny/crossref_metadata_2025 huggingface dataset:
Estimating the Pareto plus noise distribution parameters using non‐integer order moments and [zlog(z)] approaches
Authors: Mezache Amar , Chalabi Izzeddine , Soltani Faouzi , Sahed Mohamed
Published: August 2015

Pareto plus noise clutter distribution has been introduced recently as a good candidate model for X‐band high resolution maritime clutter returns. In this study, the authors derive a non‐integer order moments estimator (NIOME) and [zlog(z)] based estimator to find the parameters of this distribution in the case of non‐coherent integration of N‐pulses. For this, the authors first develop an asymptotic formula of moments with non‐integer order which is expressed in terms of the gamma and the generalised hypergeometric functions. Then, the authors derive [zlog(z)] based approach as a function of the log based moments and the generalised hypergeometric function. By accommodating a non‐integer moments and moments of orders one and two, the proposed estimators are given so that non‐linear estimates of the shape parameter are achieved using numerical computations. Through synthetic and real data, the authors show numerous examples demonstrating the applicability of the estimation procedures as a function of clutter‐plus‐noise parameters. The obtained results illustrate that the proposed NIOME method is asymptotically efficient especially for multiple looks case and high sample size.
Experimental characterisation and performance evaluation of a coaxial current transformer for measurement of insulated gate bipolar transistor switching current
Authors: Ghosh Saikat Subhra , Narayanan Gopalaratnam
Published: August 2015

Measurement of device current during switching characterisation of an insulated gate bipolar transistor (IGBT) requires a current sensor with low insertion impedance and high bandwidth. This study presents an experimental procedure for evaluating the performance of a coaxial current transformer (CCT), designed for the above purpose. A prototype CCT, which can be mounted directly on a power terminal of a 1200 V/50 A half‐bridge IGBT module, is characterised experimentally. The measured characteristics include insertion impedance, gain and phase of the CCT at different frequencies. The bounds of linearity within which the CCT can operate without saturation are determined theoretically, and are also verified experimentally. The experimental study on linearity of the CCT requires a high‐amplitude current source. A proportional–resonant (PR) controller‐based current‐controlled half‐bridge inverter is developed for this purpose. A systematic procedure for selection of PR controller parameters is also reported in this study. This set‐up is helpful to determine the limit of linearity and also to measure the frequency response of the CCT at realistic amplitudes of current in the low‐frequency range.
Radiated spurious emission measurements using fast Fourier transform‐based time domain scan
Authors: Sim Zhi Wei , Song Jian
Published: August 2015

In this study, the use of time domain (TD) scan based on fast Fourier transform technique for radiated spurious emission (RSE) measurements is investigated. Measurement time and results of TD scan are compared with those of conventional frequency sweep method. The RSE measurements carried out are based on two different wireless technologies, that is, GSM 900 and GSM 1800. The findings show that the TD scan can reduce overall RSE test time up to 86% with comparable measurement results.
Hybrid method on signal de‐noising and representation for online partial discharge monitoring of power transformers at substations
Authors: Chan Jeffery C. , Ma Hui , Saha Tapan K.
Published: August 2015

To ensure reliable operations of power transformers, online condition monitoring needs to be performed. However, extensive noise can be coupled into measured signals and cause ambiguities in evaluating transformers’ conditions. This study proposes a hybrid method, which combines pre‐whitening and blind equalisation for de‐noising the signals obtained from online partial discharge (PD) measurements of transformers. A measured signal is first gone through a pre‐whitening process for initial noise reduction and then processed by blind equalisation. Finally, an equalised signal that can reveal PD source in a transformer is converted to a kurtogram for an accurate PD pattern representation. The proposed method has been applied to signals obtained from laboratory experiments and online measurements of transformers at substations. Results show that the method can effectively de‐noise PD signals contaminated by severe noise and consistently represent PD patterns induced by different PD sources.
Sensing texture using an artificial finger and a data analysis based on the standard deviation
Authors: Chappell Paul H. , Muridan Norasmahan , Hanif N. Hazrin H. Mohamad , Cranny Andy , White Neil M.
Published: August 2015

The results from experiments with a screen‐printed piezoelectric sensor, mounted on an artificial finger‐tip and including a cosmetic covering, are shown to detect surface information from regular texture patterns. For the automatic control of an artificial hand and to feedback information to the amputee, an algorithm has been developed based on the standard deviation (SD) of signal data from the sensor. The SD analysis for texture detection is novel as it uses a combination of arithmetic processes. It windows the data sequentially and calculates the SD of the data in the windows and then averages the SDs. The output from the algorithm is the frequency spectrum of a signal. Plots, from the output of the algorithm, show events that correspond to the cyclic waveforms produced from the regularity of object surface patterns. The results from the algorithm are confirmed with an analysis of the signals using fast Fourier transforms.
Electrocardiogram data compression using adaptive bit encoding of the discrete Fourier transforms coefficients
Authors: Sadhukhan Deboleena , Pal Saurabh , Mitra Madhuchhanda
Published: August 2015

This study proposes an algorithm for electrocardiogram (ECG) data compression using the conventional discrete Fourier transform. The coefficients are calculated using sine and cosine basis functions instead of complex exponentials, to avoid generation of complex coefficient values. Two well defined strategies are proposed for the choice of the significant coefficients – a fixed strategy based on the selection of a fixed band‐limiting frequency, and an adaptive strategy depending on the spectral energy distribution of the signal. The different parameters for the two strategies are empirically selected based on extensive study of a wide variety of ECG data chosen from different databases. The significant coefficients are encoded using a unique adaptive bit assignment scheme to optimise the bit usage. The bit assignment map created to store the bit allocation information is run‐length encoded to eliminate further redundancies. For the MIT‐BIH arrhythmia database, the proposed technique achieves an average compression ratio of 14.67 for the fixed strategy and 16.58 for the adaptive strategy with excellent reconstruction quality, which is quite comparable to the other reported techniques. The simplicity and low cost infrastructural requirement of the algorithm, makes it suitable for implementation on an embedded platform to be used in mobile devices.
Data integration for multi‐path ultrasonic flowmeter based on Levenberg–Marquardt algorithm
Authors: Tang Xiaoyu , Xie Xiang , Zhang Hongjian , Zhou Hongliang
Published: August 2015

Ultrasonic flowmeters have potential for wide application in natural gas and hydrogen flow measurements in China. Accurate measurement is essential; thus, data fusion of acoustic paths is of importance. A data integration method for multi‐path flowmeter measurement is introduced and investigated in this study. The novel data integration method is based on the Levenberg–Marquardt algorithm. Computational fluid dynamics has been used to simulate the flows, and a laboratory scale system was established to obtain experimental measurements. The results of the simulations and experiments reveal that the method is able to reduce measurement error compared with four traditional integration methods in flow‐rate measuring in a long straight pipe. Furthermore, both the simulation and experiment results validate the integration method for non‐ideal flow conditions, such as flow downstream a single elbow or a 180° bend. The relative errors are within 1%, instead of more than 2%, which is typical for traditional methods.
Central composite experimental design for the investigation of the influence of various conditions of anodisation on the amount of antimicrobial agent loaded on TiO2 nanotubes
Authors: Lotfi M. , Sabzi R.E. , Bahram M. , Samadi N.
Published: August 2015

TiO2 nanotubes on Ti substrate were prepared by electrochemical anodisation method. Central composite experimental design was used to design the experiments to investigate the influence of some variables on the loading of antibiotic gentamicin. A full quadratic model was used in order to find out the influence of the variables and their possible interactions and finally to estimate the optimum conditions. Titanium rods were anodised in ethylene glycol containing different amounts of ammonium fluoride and water at different voltages and different anodising times. Antibacterial activity of the nanotubes prepared under the optimum condition was evaluated by a culture test with Staphylococcus aureus bacteria.
Characterisation of ferroelectric poly(vinylidene fluoride–trifluoroethylene) film prepared by Langmuir‐Blodgett deposition
Authors: Kim Woo Young , Song Dong‐Seok , Jeon Gwang‐Jae , Kang In Ku , Shim Hyun Bin , Kim Do‐Kyung , Lee Hee Chul , Park Hongsik , Kang Shin‐Won , Bae Jin‐Hyuk
Published: August 2015

Ferroelectric polymer is a flexible memory material that is insensitive to environmental variations and lends itself to research in emerging optoelectronic applications. Using Langmuir‐Blodgett (LB) deposition technology, the thickness of a ferroelectric film can be controlled in the nanometre range, offering a pathway to molecular electronics. In this reported work, ultrathin ferroelectric polymer films were fabricated through LB deposition technology and characterised by observing the surface morphology, crystallinity and polarisation–voltage relationships. Unlike previously reported ferroelectric LB films, this work has shown a maximum remanent polarisation (PR) of 6 μC/cm2 at 35 nm, which is compatible with the thick film prepared by the spin‐coating method. In addition, the polarisation stability in terms of depolarisation was investigated, which showed that the engineering of the interface between the ferroelectric LB film and the substrate is an important, deterministic factor for reliable memory applications with high signal‐to‐noise ratios.
Preparation and characterisation of calcium citrate wires
Authors: Zhong Liangzhao , Li Junfeng , Gao Yang , Cao Wenqiang , Zhang Peicong , Lai Xuefei
Published: August 2015

Long calcium citrate wires were successfully prepared using a convenient and effective soft chemical method that involved heating the sheet precursor at an appropriate temperature in a mixture of alcohol and water for a sufficient amount of time. The X‐ray diffraction patterns showed that the crystallinity degree increased with heating time. Moreover, the (200) crystal plane was the preferential growth face that was influenced by alcohol. Such influence was ascribed to alcohol being able to change the free energy and the supersaturation state of the solution. In addition, alcohol might adsorb onto the surface of the crystal and change the growth velocity of each crystal plane. The sheet precursor progressively turned into consecutive long wires by growing along the preferential growth orientation during the dissolution–reprecipitation process. The thickness of the wires was ∼8–30 nm. Long calcium citrate wires were produced to reinforce and strengthen biomaterials or for other purposes.
Onsager’s reciprocal relations in electrolyte solutions. I. Sedimentation and electroacoustics
Authors: Gourdin-Bertin S. , Chassagne C. , Bernard O. , Jardat M.
Published: August 2015

In the framework of irreversible thermodynamics, we show that the sedimentation current in electrolyte solutions is mathematically equivalent to the low frequency limit of the ionic vibration current, appearing in the presence of an acoustic wave. This non-trivial result is obtained thanks to a careful choice of the reference frame used to express the mass fluxes in the context of electroacoustics. Coupled transport phenomena in electrolyte solutions can also be investigated in a mechanical framework, with a set of Newtonian equations for the dynamics of charged solutes. Both in the context of sedimentation and of electroacoustics, we show that the results obtained in the mechanical framework, in the ideal case (i.e., without interactions between ions), do satisfy the Onsager’s reciprocal relations. We also derive the general relation between corrective forces accounting for ionic interactions which must be fulfilled so that the Onsager’s reciprocal relations are verified. Finally, we show that no additional diffusion term needs to be taken into account in the flux of solutes (far from the walls), even if local concentration gradients exist, contrarily to what was done previously in the literature.
Onsager’s reciprocal relations in electrolyte solutions. II. Effect of ionic interactions on electroacoustics
Authors: Gourdin-Bertin S. , Chassagne C. , Bernard O. , Jardat M.
Published: August 2015

In electrolyte solutions, an electric potential difference, called the Ionic Vibration Potential (IVP), related to the ionic vibration intensity, is generated by the application of an acoustic wave. Several theories based on a mechanical framework have been proposed over the years to predict the IVP for high ionic strengths, in the case where interactions between ions have to be accounted for. In this paper, it is demonstrated that most of these theories are not consistent with Onsager’s reciprocal relations. A new expression for the IVP will be presented that does fulfill the Onsager’s reciprocal relations. We obtained this expression by deriving general expressions of the corrective forces describing non-ideal effects in electrolyte solutions.
Role of low temperature resistivity on fast electron transport in disordered aluminium and copper
Authors: Blackman David R. , Robinson A. P. L. , Pasley John
Published: August 2015

To determine the link between the onset of the filamentation instability and the low temperature resistivity of the cold-electron plasma, a comparison between the transport of fast electrons through disordered aluminium and copper targets is made using the hybrid code Zephyros. The filamentation instability is suppressed at laser intensities below 5×1019 Wcm-2 for materials where the resistivity of the material is lower than 1μΩm at 1 eV. Interestingly, copper targets show larger resistive magnetic field growth, and as a result, more collimation of the electron beam, despite having a consistently smaller resistivity at lower temperatures than that of aluminium. The increase in magnetic field strength is responsible for the suppression of the filamentation instability. This is due to the resistive filamentation growth rate for copper and aluminium, under identical conditions, being numerically very close.
Amorphous silicon carbide passivating layers for crystalline-silicon-based heterojunction solar cells
Authors: Boccard Mathieu , Holman Zachary C.
Published: August 2015

Amorphous silicon enables the fabrication of very high-efficiency crystalline-silicon-based solar cells due to its combination of excellent passivation of the crystalline silicon surface and permeability to electrical charges. Yet, amongst other limitations, the passivation it provides degrades upon high-temperature processes, limiting possible post-deposition fabrication possibilities (e.g., forcing the use of low-temperature silver pastes). We investigate the potential use of intrinsic amorphous silicon carbide passivating layers to sidestep this issue. The passivation obtained using device-relevant stacks of intrinsic amorphous silicon carbide with various carbon contents and doped amorphous silicon are evaluated, and their stability upon annealing assessed, amorphous silicon carbide being shown to surpass amorphous silicon for temperatures above 300 °C. We demonstrate open-circuit voltage values over 700 mV for complete cells, and an improved temperature stability for the open-circuit voltage. Transport of electrons and holes across the hetero-interface is studied with complete cells having amorphous silicon carbide either on the hole-extracting side or on the electron-extracting side, and a better transport of holes than of electrons is shown. Also, due to slightly improved transparency, complete solar cells using an amorphous silicon carbide passivation layer on the hole-collecting side are demonstrated to show slightly better performances even prior to annealing than obtained with a standard amorphous silicon layer.
The role of fluctuations in bistability and oscillations during the H2 + O2 reaction on nanosized rhodium crystals
Authors: Grosfils P. , Gaspard P. , Visart de Bocarmé T.
Published: August 2015

A combined experimental and theoretical study is presented of fluctuations observed by field ion microscopy in the catalytic reaction of water production on a rhodium tip. A stochastic approach is developed to provide a comprehensive understanding of the different phenomena observed in the experiment, including burst noise manifesting itself in a bistability regime, noisy oscillations, and nanopatterns with a cross-like oxidized zone separating the surface into four quadrants centered on the {111} facets. The study is based on a stochastic model numerically simulating the processes of adsorption, desorption, reaction, and transport. The surface diffusion of hydrogen is described as a percolation process dominated by large clusters corresponding to the four quadrants. The model reproduces the observed phenomena in the ranges of temperature, pressures, and electric field of the experiment.
Effects of collisions on conservation laws in gyrokinetic field theory
Authors: Sugama H. , Watanabe T.-H. , Nunami M.
Published: August 2015

Effects of collisions on conservation laws for toroidal plasmas are investigated based on the gyrokinetic field theory. Associating the collisional system with a corresponding collisionless system at a given time such that the two systems have the same distribution functions and electromagnetic fields instantaneously, it is shown how the collisionless conservation laws derived from Noether's theorem are modified by the collision term. Effects of the external source term added into the gyrokinetic equation can be formulated similarly with the collisional effects. Particle, energy, and toroidal momentum balance equations including collisional and turbulent transport fluxes are systematically derived using a novel gyrokinetic collision operator, by which the collisional change rates of energy and canonical toroidal angular momentum per unit volume in the gyrocenter space can be given in the conservative forms. The ensemble-averaged transport equations of particles, energy, and toroidal momentum given in the present work are shown to include classical, neoclassical, and turbulent transport fluxes which agree with those derived from conventional recursive formulations.
Deviation from threshold model in ultrafast laser ablation of graphene at sub-micron scale
Authors: Gil-Villalba A. , Xie C. , Salut R. , Furfaro L. , Giust R. , Jacquot M. , Lacourt P. A. , Dudley J. M. , Courvoisier F.
Published: August 2015

We investigate a method to measure ultrafast laser ablation threshold with respect to spot size. We use structured complex beams to generate a pattern of craters in CVD graphene with a single laser pulse. A direct comparison between beam profile and SEM characterization allows us to determine the dependence of ablation probability on spot-size, for crater diameters ranging between 700 nm and 2.5 μm. We report a drastic decrease of ablation probability when the crater diameter is below 1 μm which we interpret in terms of free-carrier diffusion.
Improved non-local electron thermal transport model for two-dimensional radiation hydrodynamics simulations
Authors: Cao Duc , Moses Gregory , Delettrez Jacques
Published: August 2015

An implicit, non-local thermal conduction algorithm based on the algorithm developed by Schurtz, Nicolai, and Busquet (SNB) [Schurtz et al., Phys. Plasmas 7, 4238 (2000)] for non-local electron transport is presented and has been implemented in the radiation-hydrodynamics code DRACO. To study the model's effect on DRACO's predictive capability, simulations of shot 60 303 from OMEGA are completed using the iSNB model, and the computed shock speed vs. time is compared to experiment. Temperature outputs from the iSNB model are compared with the non-local transport model of Goncharov et al. [Phys. Plasmas 13, 012702 (2006)]. Effects on adiabat are also examined in a polar drive surrogate simulation. Results show that the iSNB model is not only capable of flux-limitation but also preheat prediction while remaining numerically robust and sacrificing little computational speed. Additionally, the results provide strong incentive to further modify key parameters within the SNB theory, namely, the newly introduced non-local mean free path. This research was supported by the Laboratory for Laser Energetics of the University of Rochester.
An itinerant oscillator model with cage inertia for mesorheological granular experiments
Authors: Lasanta Antonio , Puglisi Andrea
Published: August 2015

Recent experiments with a rotating probe immersed in weakly fluidized granular materials show a complex behavior on a wide range of time scales. Viscous-like relaxation at high frequency is accompanied by an almost harmonic dynamical trapping at intermediate times, with possibly anomalous long time behavior in the form of super-diffusion. Inspired by the itinerant oscillator model for diffusion in molecular liquids, and other models with coupled thermostats acting at different time scales, here we discuss a new model able to account for fast viscous relaxation, dynamical trapping, and super-diffusion at long times. The main difference with respect to liquids is a non-negligible cage inertia for the surrounding (granular) fluid, which allows it to sustain a slow but persistent motion for long times. The computed velocity power density spectra and mean-squared displacement qualitatively reproduce the experimental findings. We also discuss the linear response to external perturbations and the tail of the distribution of persistency time, which is associated with superdiffusion, and whose cut-off time is determined by cage inertia.
Structural transformations in Ge2Sb2Te5 under high pressure and temperature
Authors: Mio A. M. , Privitera S. , D'Arrigo G. , Ceppatelli M. , Gorelli F. , Santoro M. , Miritello M. , Bini R. , Rimini E.
Published: August 2015

The structural transformations occurring in Ge2Sb2Te5 films heated at temperature up to 400 °C, and under hydrostatic pressure up to 12 GPa, have been investigated through in-situ X ray diffraction measurements. The adopted experimental conditions are close to those experienced by the phase change material during the SET (crystallization)/RESET (amorphization) processes in a nonvolatile memory device. The compression enhances the thermal stability of the amorphous phase, which remains stable up to 180 °C at 8 GPa and to 230 °C at 12 GPa. The structure of the crystalline phases is also modified, with the formation of a CsCl-type structure instead of rock-salt and of a GeS-type structure at the temperature at which usually the trigonal stable phase is formed. Overall, the stability of the stable phase appears to be more affected by the compression. We argue that the presence of weak bonds associated to the van der Waals gaps is a determining factor for the observed reduced stability.
A novel Gaussian-Sinc mixed basis set for electronic structure calculations
Authors: Jerke Jonathan L. , Lee Young , Tymczak C. J.
Published: August 2015

A Gaussian-Sinc basis set methodology is presented for the calculation of the electronic structure of atoms and molecules at the Hartree–Fock level of theory. This methodology has several advantages over previous methods. The all-electron electronic structure in a Gaussian-Sinc mixed basis spans both the “localized” and “delocalized” regions. A basis set for each region is combined to make a new basis methodology—a lattice of orthonormal sinc functions is used to represent the “delocalized” regions and the atom-centered Gaussian functions are used to represent the “localized” regions to any desired accuracy. For this mixed basis, all the Coulomb integrals are definable and can be computed in a dimensional separated methodology. Additionally, the Sinc basis is translationally invariant, which allows for the Coulomb singularity to be placed anywhere including on lattice sites. Finally, boundary conditions are always satisfied with this basis. To demonstrate the utility of this method, we calculated the ground state Hartree–Fock energies for atoms up to neon, the diatomic systems H2, O2, and N2, and the multi-atom system benzene. Together, it is shown that the Gaussian-Sinc mixed basis set is a flexible and accurate method for solving the electronic structure of atomic and molecular species.
Asymmetric wall force and toroidal rotation in tokamak disruptions
Authors: Strauss H.
Published: August 2015

This paper investigates the scaling of asymmetric wall force and toroidal rotation during tokamak disruptions. It is shown by simulations and analysis how these effects depend on the displacement in an asymmetric vertical displacement event (AVDE) and on 3D magnetic field perturbation amplitude. The simulations include a sequence of both upward and downward displacements. It is verified that the asymmetric force is proportional to the vertical current moment, which in turn is proportional to the product of vertical displacement and the magnetic perturbation amplitude. It is verified how the scaling of toroidal rotation in AVDE disruptions depends on magnetic perturbation amplitude, vertical displacement, and βN.
A time domain two-particle approximation to calculate the absorption and circular dichroism line shapes of molecular aggregates
Authors: Song Kai , Bai Shuming , Shi Qiang
Published: August 2015

The hierarchical equations of motion (HEOM) method has recently emerged as an effective approach to simulate linear and nonlinear spectroscopic signals of molecular aggregates in the intermediate coupling regime. However, its application to large systems is still limited when there are a large number of molecules in the molecular aggregate. In this work, we propose a time domain two-particle approximation (TPA) in combination with the HEOM method to calculate the absorption and circular dichroism line shapes of molecular aggregates. The new method is shown to reduce the number of auxiliary density operators (ADOs) significantly for large systems, and a further truncation of the two-bath-set excited terms based on geometric considerations can lead to a linear increase of the number of ADOs with the system size. The validity of the HEOM-TPA method is first tested on one-dimensional model systems. The new method is then applied to calculate the absorption and circular dichroism line shapes of the Photosystem I core complex, as well as the population evolution of the Fenna-Matthews-Olson complex to demonstrate its effectiveness.
Surface plasmon polariton excitation by electrostatic modulation and phase grating in indium-tin-oxide coated lithium niobate slabs
Authors: Wang Hao , Zhang Jingwen , Zhao Hua
Published: August 2015

Excitation of surface plasmon polaritons (SPPs) in a non-metal system in visible regime is discussed. With the assistance of phase grating resulted from photorefractive effect and electrostatic modulation of ITO induced by strong photovoltaic effect in iron-doped LiNbO3, phase matching condition could be satisfied for SPP excitation in this semiconductor/dielectric system. Both the phase grating instead of metal grating and electrostatic modulation of semiconductor could be used for the design of tunable plasmonic devices based on nonlinear photorefractive crystals.
Effect of the maize–soybean intercropping system on the potential bioavailability of magnesium, iron and zinc
Authors: Dragicevic Vesna , Oljaca Snezana , Stojiljkovic Milovan , Simic Milena , Dolijanovic Zeljko , Kravic Natalija
Published: August 2015

This study concerned the effect of different intercropping systems (alternating rows and alternating strips) of maize and soybean compared with single cropping, in combination with different fertilisers (biofertiliser, organic fertiliser, and urea) on the potential availability of magnesium (Mg), iron (Fe) and zinc (Zn) from grain, through their ratio with phytate (as inhibitor) and β-carotene (as promoter). The higher grain yield and land equivalent ratio obtained under alternating rows + biofertiliser treatment demonstrated the improved ability of crops in close proximity for better utilisation of existing agro-ecological conditions. Alternating rows + organic fertiliser decreased the molar ratios phytate : β-carotene, phytate : Fe, phytate : Mg and phytate : Zn, indicating increased availability of the mineral elements in both crops. However, alternating strips + organic fertiliser contributed mostly to an increase in β-carotene, Mg, Fe and Zn concentrations in soybean. Increased grain yield of both crops was followed by decrease in β-carotene and increase in phytate, particularly in maize. In soybean, β-carotene could be considered as the main contributor to Fe availability. Accordingly, cropping in alternating rows or strips, combined with biofertilisers, could serve as fortification measures for improved nutritional quality of maize and soybean grain, without grain yield losses.
Sovereignty, the ‘resource curse’ and the limits of good governance: a political economy of oil in Ghana
Authors: Phillips Jon , Hailwood Elena , Brooks Andrew
Published: August 2015

The idea of a resource curse has influenced policy makers and led to calls for good governance to avoid the pitfalls of oil sector development. Through discussion of Ghana's recent insertion into the global political economy of oil, this paper describes the limits of the resource curse framing and associated liberal institutional management approaches to the inherently political nature of oil exploration and production. The paper describes ways in which sovereignty has been exercised both in opposition to and in support of foreign capital, and the role of discourses of ‘good governance’ in structuring the material politics of resource access.
Induction of tetraploidity with antimicrotubule agents in oriental melon (Cucumis melo var. Makuwa)
Authors: Wang Kang , He Linchi , Yan Honglang , Wei Xiaoyun
Published: August 2015

Polyploidy induction is an important method for the innovation of germplasm resources because polyploid plants have superior characteristics to diploid ones. In this paper, oriental melon (Cucumis melovar. makuwa) tetraploids were induced by treating the apical meristem of seedlings with oryzalin, amiprophos-methyl (APM) and colchicine. The results showed that each of these three antimicrotubule agents could induce the formation of tetraploid oriental melon, but oryzalin and APM showed higher efficiencies of tetraploid induction. The efficiencies of tetraploid induction were highest (14.44%) when treated with 80 µmol·L−1APM for 6 days. Stomata characteristics were used to screen the treated plants for changes in ploid levels preliminarily. Subsequently, the changes in ploid levels were further confirmed by flow-cytometric analysis and chromosome counts of root tip cells. The comparison between diploids and tetraploids in fruit characteristics, reproductive characteristics, and postharvest storage qualities showed that the fruit of tetraploids had thicker flesh, higher total soluble solid (TSS) content and lower fruit shape index than diploids. The pollen grains of tetraploids were larger but showed lower vitality. In addition, a higher percentage of embryo-deficient seeds contributed to lower fertility. During postharvest storage, the fruit of tetraploids softened faster, had higher TSS content and lower respiration rate.
Training the inspiratory muscles improves running performance when carrying a 25 kg thoracic load in a backpack
Authors: Faghy Mark A. , Brown Peter I.
Published: August 2015

Load carriage (LC) exercise in physically demanding occupations is typically characterised by periods of low‐intensity steady‐state exercise and short duration, high‐intensity exercise while carrying an external mass in a backpack; this form of exercise is also known as LC exercise. This induces inspiratory muscle fatigue and reduces whole‐body performance. Accordingly we investigated the effect of inspiratory muscle training (IMT, 50% maximal inspiratory muscle pressure (PImax) twice daily for six week) upon running time‐trial performance with thoracic LC. Nineteen healthy males formed a pressure threshold IMT (n = 10) or placebo control group (PLA; n = 9) and performed 60 min LC exercise (6.5 km h–1) followed by a 2.4 km running time trial (LCTT) either side of a double‐blind six week intervention. Prior to the intervention, PImax was reduced relative to baseline, post‐LC and post‐LCTT in both groups (pooled data: 13 ± 7% and 16 ± 8%, respectively, p < .05) and similar changes were observed post‐PLA. Post‐IMT only, resting PImax increased +31% (p < .05) and relative to pre‐IMT was greater post‐LC (+19%) and post‐LCTT (+18%, p < .05), however, the relative reduction in PImax at each time point was unchanged (13 ± 11% and 17 ± 9%, respectively, p > .05). In IMT only, heart rate and perceptual responses were reduced post‐LC (p < .05). Time‐trial performance was unchanged post‐PLA and improved 8 ± 4% after IMT (p < .05). In summary, when wearing a 25 kg backpack, IMT attenuated the cardiovascular and perceptual responses to steady‐state exercise and improved high‐intensity time‐trial performance which we attribute in part to reduced relative work intensity of the inspiratory muscles due to improved inspiratory muscle strength. These findings have real‐world implications for occupational contexts.
Overshadowing and latent inhibition in nausea-based context conditioning in humans: Theoretical and practical implications
Authors: Hall Geoffrey , Stockhorst Ursula , Enck Paul , Klosterhalfen Sibylle
Published: August 2015

Volunteer participants underwent nausea-inducing body rotation in a distinctive context, and the acquired ability of the contextual cues to evoke nausea was subsequently assessed by a symptom rating scale. One group received prior exposure to the context (a latent inhibition procedure); a second consumed a novel flavour prior to rotation (an overshadowing procedure); a third group experienced both procedures; and a control group received neither. When tested in the context in the absence of rotation, all groups reported an increase in nausea-related symptoms at the time when rotation had previously occurred, an outcome consistent with the occurrence of conditioned nausea. The magnitude of this increase did not differ across the groups, but the overall level of responsiveness (the degree to which nausea-related symptoms were reported) was enhanced in the latent inhibition and reduced in the overshadowing condition. Cortisol levels showed the same pattern. The implications of these findings for the proposal that overshadowing and latent inhibition procedures might be used to control the development of anticipatory nausea in patients undergoing chemotherapy is considered.
SNARC (spatial–numerical association of response codes) meets SPARC (spatial–pitch association of response codes): Automaticity and interdependency in compatibility effects
Authors: Weis Tina , Estner Barbara , van Leeuwen Cees , Lachmann Thomas
Published: August 2015

Concepts, including the mental number line, or addressing pitch as high and low, suggest that the spatial–numerical and spatial–pitch association of response codes (SNARC and SPARC) effects are domain-specific and thus independent. Alternatively, there may be dependencies between these effects, because they share common automatic or controlled decision mechanisms. In two experiments, participants were presented with spoken numbers in different pitches; their numerical value, pitch, and response compatibility were varied systematically. This allowed us to study SNARC and SPARC effects in a factorial design (see also Fischer, Riello, Giordano, & Rusconi, 2013). Participants judged the stimuli on numerical magnitude, pitch, or parity (odd–even). In all tasks, the SNARC and SPARC effects had superadditive interactions. These were interpreted as both effects sharing a common mechanism. The task variation probes the mechanism: In the magnitude judgement task, numerical magnitude was explicit, whereas pitch was implicit; in the pitch judgement task, it was vice versa. In the parity judgement task, both dimensions were implicit. Regardless of whether they were implicit or explicit, both SNARC and SPARC effects occurred in all tasks. We concluded that by not requiring focal attention the common mechanism operates automatically.
cyNeo4j: connecting Neo4j and Cytoscape
Authors: Summer Georg , Kelder Thomas , Ono Keiichiro , Radonjic Marijana , Heymans Stephane , Demchak Barry
Published: August 2015

Summary: We developed cyNeo4j, a Cytoscape App to link Cytoscape and Neo4j databases to utilize the performance and storage capacities Neo4j offers. We implemented a Neo4j NetworkAnalyzer, ForceAtlas2 layout and Cypher component to demonstrate the possibilities a distributed setup of Cytoscape and Neo4j have.

Availability and implementation: The app is available from the Cytoscape App Store at http://apps.cytoscape.org/apps/cyneo4j, the Neo4j plugins at www.github.com/gsummer/cyneo4j-parent and the community and commercial editions of Neo4j can be found at http://www.neo4j.com.

Contact:  georg.summer@gmail.com
Evaluating the effectiveness of a seasonal spawning area closure
Authors: Clarke J. , Bailey D. M. , Wright P. J.
Published: August 2015

Fish that aggregate at predictable locations and times to spawn are often vulnerable to over-exploitation. Seasonal closures have often been implemented in an attempt to alleviate such impacts but the effectiveness of these measures is rarely tested. This study evaluates the effectiveness of a spawning closure for Atlantic cod (Gadus morhua) in the Firth of Clyde off the Scottish West Coast (ICES Area VIa). This closure was introduced in March 2001 as an emergency measure to allow as many cod as possible to spawn and avoid the build-up of displaced effort from another spawning closure. Genetic, tagging, and otolith microchemistry investigations indicate that cod inhabiting the Clyde are reproductively isolated from other resident groups in the central and northern part of the Scottish West Coast stock. This study used a beyond-Before-After, Control-Impact approach to compare population trends of the Clyde spawning aggregation before and after the introduced area closure, using two other sub-population spawning grounds as control areas. There was no evidence of local recovery in terms of abundance, biomass, or reduced mortality in the Clyde more than a decade after establishing the closure. Mortality may have remained high because young cod are still caught as bycatch in the Nephrops fishery in the area and the predation rate may have increased due to an expanding whiting population. Considering the state of the already severely depleted Clyde sub-population when the closure was implemented the measure appears to have been too little and too late. The tendency to implement such spawning closures on nearly collapsed stocks may be why these measures often appear to have been ineffective.
Prophylactic bilateral salpingectomy for the prevention of ovarian cancers: What is happening in Italy?
Authors: Venturella Roberta , Rocca Morena , Lico Daniela , Trapasso Simona , Di Cello Annalisa , Gizzo Salvatore , Zullo Fulvio , Morelli Michele
Published: August 2015

In 2011, the Society of Gynecologic Oncology of Canada encouraged physicians to discuss with their patients the risks and benefits of prophylactic bilateral salpingectomy (PBS) at the time of hysterectomy or tubal ligation for prevention of ovarian cancers (OCs). The aim of this study was to examine obstetrician–gynaecologists’ knowledge, opinions and practice patterns relating to opportunistic salpingectomy in the general population. An anonymous electronic survey was sent to residents, academic and hospital staff in Italian OBGYN departments. The survey included questions on demographics, knowledge and attitudes in terms of the implementation of PBS in women at average population risk of OC. At least 80% of the 479 respondents reported performing PBS during hysterectomy for benign indications, chiefly with the intent of OC risk reduction but also to decrease the risk of reoperation and subsequent tubal pathologies. Among the 86 colleagues who do not routinely perform PBS, more than 50% stated that they have doubts regarding the benefits associated with the procedure. Most of the respondents declared that they were familiar with the literature on the topic and were aware of the data reporting the safety of the procedure, and only 21 (4.53%) had never heard of PBS. Over 40% of the respondents worked in hospitals in southern Italy. PBS as a prophylactic measure to reduce the incidence of OC is a well-known strategy among the Italian OBGYNs interviewed. Given the unequal distribution of respondents, however, wider educational initiatives should be undertaken, at least in Italy, to increase the implementation of salpingectomy among OBGYNs.
Risk of Gastrointestinal Events During Vandetanib Therapy in Patients With Cancer: A Systematic Review and Meta-analysis of Clinical Trials
Authors: Yang XiongWen , Pan Xiong , Cheng Xiaoshu , Kuang YuKang , Cheng YingZhang
Published: August 2015

Vandetanib, a tyrosine kinase inhibitor used as an anticancer therapeutic agent, has adverse events associated with treatment resulting in noncompliance and withdrawal from the therapy. Here, we performed meta-analysis of published clinical trials to determine relative risk (RR) and incidence of gastrointestinal events during vandetanib therapy in patients with cancer. A comprehensive literature search was performed and summary incidence, RR, and 95% confidence intervals (CIs) were calculated employing fixed- or random-effects models, depending on the heterogeneity of trials. Twenty-two trials with 6382 patients were included summary incidences of all-grade gastrointestinal events in patients with cancer were anorexia 24% (95% CI, 20%–28%), constipation 17% (95% CI, 13%–20%), diarrhea 46% (95% CI, 40%–53%), nausea 29% (95% CI, 25%–33%), and vomiting 17% (95% CI, 14%–21%). Incidences of vandetanib-associated gastrointestinal events stratified by tumor histology were statistically insignificant. Vandetanib was associated with a significant risk of all-grade diarrhea (RR 1.75, 95% CI, 1.42–2.16) and high-grade diarrhea (RR 1.94, 95% CI, 1.43–2.64) and significantly decreased risk of all-grade constipation (RR 0.80, 95% CI, 0.71–0.91). Summary RR showed a significant risk of vandetanib-associated constipation (RR 0.82, 95% CI, 0.72–0.93) and diarrhea (all-grade: RR 1.68, 95% CI, 1.31–2.14 and high-grade: RR 1.57, 95% CI, 1.14–2.17) in patients with non–small-cell lung cancer. This study revealed a significantly increased risk of diarrhea and a reduced risk of constipation in patients with cancer receiving vandetanib, suggesting that appropriate and frequent clinical monitoring should be emphasized.
Eleven Basic Procedures/Practices for Dental Patient Safety
Authors: Perea-Pérez Bernardo , Labajo-González Elena , Acosta-Gío A. Enrique , Yamalik Nermin
Published: August 2015

Objectives

This study aimed to help alleviate the shortage of reliable information on clinical care issues; the Spanish Observatory of Dental Patient Safety (OESPO) has resorted to the study of legal claims by patients and searched those which produced clinical problems.

Methods

Based on OESPO data, this article proposes 11 basic procedures/practices for dental patient safety to help mitigate most preventable adverse events.

Results

The sample of the OESPO is large (415 adverse events studied), but it has the bias of a judicial source. However, the results provide an interesting approach to clinical safety in dentistry. When studying in detail the causes that led to preventable adverse events, it can be seen that most of these (and most severe) events have been caused by a small number of erroneous behaviors.

Conclusions

Most preventable adverse events during the dental health care are produced by a relatively small number of causes. Therefore, a few basic safety procedures can reduce significantly these preventable adverse events.
Maribacter flavus sp. nov., isolated from a cyanobacterial culture pond
Authors: Tang Mingxing , Wang Guanghua , Xiang Wenzhou , Chen Chenghao , Wu Jiayi , Dai Shikun , Wu Hualian , Li Tao , Wu Houbo
Published: August 2015

A Gram-stain-negative, yellow, non-spore-forming, strictly aerobic bacterium, designated C3T, was isolated from a cyanobacterial culture pond. Cells were halophilic, rod-shaped and able to move by gliding. Growth of strain C3T was observed at 15–30 °C (optimum 25 °C), pH 6.0–9.0 (optimum pH 7.5), and in the presence of 1–7 % (w/v) NaCl (optimum 2–3 %). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain C3T formed a distinct lineage within the family Flavobacteriaceae and exhibited the highest similarity (95.21 %) to the type strains of Maribacter dokdonensis, Maribacter arcticus, Maribacter orientalis and Maribacter stanieri, and ‘Maribacter caenipelagi’ HD-44. The only isoprenoid quinone present within strain C3T was menaquinone 6 (MK-6). The G+C content of genomic DNA was 41.5 mol%. The major polar lipids were phosphatidylethanolamine and three unidentified lipids. The predominant cellular fatty acids (>5 % of the total fatty acids) were iso-C15 : 1 G, iso-C15 : 0, iso-C15 : 0 3-OH, iso-C17 : 0 3-OH, and summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c). On the basis of the phenotypic, chemotaxonomic and phylogenetic characteristics, strain C3T represents a novel species of the genus Maribacter, for which the name Maribacter flavus sp. nov. is proposed. The type strain is C3T ( = KCTC 42508T = CGMCC 1.15112T).