bluuebunny/crossref_metadata_2025 huggingface dataset:
MicroRNA-199a-3p and microRNA-34a regulate apoptosis in human osteosarcoma cells
Authors: Tian Ye , Zhang Ying-Ze , Chen Wei
Published: June 2014

miRNAs (microRNAs) are small non-coding RNAs [18–25 nt (nucleotides)] that regulate gene expression mainly through affecting post-transcriptional modification. Osteosarcoma is an aggressive sarcoma of the bone characterized by a high level of genetic instability and recurrent DNA deletions and amplifications. miRNAs play an important role in cancer cell growth and migration; however, the potential roles of miRNAs in osteosarcoma remain largely uncharacterized. In this paper, miR-199a and miR-34a were discussed the mechanisms of apoptosis using miRNA mimics in human osteosarcoma cells. The results demonstrated that miR-199a and miR-34a could induce the apoptosis of human osteosarcoma cells via p53 signalling pathway.
Dialect Awareness and Lexical Comprehension of Mainstream American English in African American English–Speaking Children
Authors: Edwards Jan , Gross Megan , Chen Jianshen , MacDonald Maryellen C. , Kaplan David , Brown Megan , Seidenberg Mark S.
Published: June 2014

Purpose

This study was designed to examine the relationships among minority dialect use, language ability, and young African American English (AAE)–speaking children's understanding and awareness of Mainstream American English (MAE).

Method

Eighty-three 4- to 8-year-old AAE-speaking children participated in 2 experimental tasks. One task evaluated their awareness of differences between MAE and AAE, whereas the other task evaluated their lexical comprehension of MAE in contexts that were ambiguous in AAE but unambiguous in MAE. Receptive and expressive vocabulary, receptive syntax, and dialect density were also assessed.

Results

The results of a series of mixed-effect models showed that children with larger expressive vocabularies performed better on both experimental tasks, relative to children with smaller expressive vocabularies. Dialect density was a significant predictor only of MAE lexical comprehension; children with higher levels of dialect density were less accurate on this task.

Conclusions

Both vocabulary size and dialect density independently influenced MAE lexical comprehension. The results suggest that children with high levels of nonmainstream dialect use have more difficulty understanding words in MAE, at least in challenging contexts, and suggest directions for future research.
Aggregate domestic demand modelling for the next day direct load control applications
Authors: Bina Mohammad Tavakoli , Ahmadi Danial
Published: June 2014

A large group of residential appliances can be controlled by an aggregator as a single entity to reduce their aggregate energy consumption at peak periods. The target of this study is concentrated on proposing a new strategy from the perspective of an aggregator that optimally schedules residential loads during the next day. In this research, Gaussian copula (GC) function and Gaussian mixture model (GMM) are investigated as new efficient tools to estimate the aggregate power demand of specific domestic appliances. Since copula function considers the correlation of the exact data in generating new data, the estimation would lead to much more accurate solutions in practice compared to other estimating functions. However, the GMM estimates data with about 5% reduction in prediction error compared to those of the GC. A semi‐automated demand response is required for the aggregator to apply the proposed strategy to the flexible loads, including dish washer, washing machine and electrical vehicle. Moreover, a mathematical formulation for the objective function is also introduced in which both the peak demand and energy cost are treated by a stochastic non‐linear programming. Finally, the proposed strategy was simulated with the GAMS as an optimisation tool.
Generalised noise cancellation method for wave estimation by HF surface wave radar
Authors: Wang Wei , Wyatt Lucy
Published: June 2014

High frequency (HF) surface wave radar (HFSWR) has been demonstrated, in many experiments and papers, to be a powerful tool for sea‐state detection. However, the availability and accuracy of the HFSWR measurements are limited by various unwanted clutter and interferences (collectively called ‘noise’) that contaminate the radar received signals, especially for wave estimation. This study extends the image recognition, segmentation and subspace projection method for removing the radio frequency interference developed in the previous study, to the mitigation of more general types of noise. Applications of this generalised method are presented. The results show that the noise can be largely removed regardless of their correlation in Doppler or range, their size in the range‐Doppler domain and whether they are homogeneous or inhomogeneous. The effectiveness of all these approaches is validated by using data obtained with the Pisces HF radar, which is a high‐performance radar developed for long‐range wave measurement, operating in the lower half of the HF band (5–10‐MHz).
Textural lacunarity for semi‐supervised detection in sonar imagery
Authors: Nelson James Daniel Bryan , Krylov Vladimir
Published: June 2014

Wavelet energy‐based lacunarity features, which measure deviations from translational statistical invariance over multiple scales, were recently proposed for object detection and classification in sonar imagery. The authors here extend the idea to incorporate further robustness to background type whilst retaining sensitivity to local changes in texture caused by the presence of man‐made objects. The resulting textural‐lacunarity features are constructed by estimating the joint distribution of local neighbourhoods with empirical distributions over an adaptive texton dictionary. Experiments on a synthetic aperture sonar imagery dataset suggest that the features offer significant improvements in the receiver operating curve.
Remote visual monitoring of analogue meter displays using deformable models
Authors: Behaine Carlos Alberto Ramirez , Scharcanski Jacob
Published: June 2014

Visual monitoring of analogue meters is a critical task especially in isolated locations. Active shape models (ASMs) allow modelling of arbitrary shapes, even when they deform, by a shape adaptive technique. In this study, the authors describe a new ASM scheme for remote reading of panels with multiple analogue displays. Assuming a trained ASM for a given meter shape, the proposed scheme departs from a collection of landmark points detected in the input colour image, and makes meter readings by matching the meter pointer shape (position and orientation). The preliminary experimental results indicate that the authors’ ASM scheme enhances the performance of automatic visual monitoring in contrast to human reading and other ASM approaches.
Statistics of polarisation matching
Authors: Naus H.W.L. , Zwamborn A.P.M.
Published: June 2014

The reception of electromagnetic signals depends on the polarisation matching of the transmitting and receiving antenna. The practical matching differs from the theoretical one because of the noise deterioration of the transmitted and eventually received electromagnetic field. In other applications, the polarisation parameters of the receiving antenna are not known. Both problems are addressed by means of statistical methods, analytical as well as simulation results are obtained. The variation of the noisy matching factor depends mainly on the signal‐to‐noise ratio. The resulting probability distribution for the polarisation matching factor in case of a stochastic receiver is independent of the phase difference, but strongly affected by the axis ratio of the incident polarised field.
A multifunctional real‐time power quality monitoring system using Stockwell transform
Authors: Reddy Maddikara Jaya Bharata , Sagar Kondaveti , Mohanta Dusmanta Kumar
Published: June 2014

The proliferation of power electronic devices in the power sector has intensified the power quality (PQ) issues. Identification of these PQ issues is one of the most important steps for their effective elimination. Hence, development of a real‐time (hardware) PQ monitoring system is of great research interest. This study proposes a multifunctional real‐time (hardware) PQ monitoring system using Stockwell transform (S‐transform). The proposed system is designed and implemented in LabVIEW environment, which can display the real‐time fast Fourier transform plots, root‐mean‐square values, harmonic components, values of total harmonic distortion and three‐dimensional plots of S‐transform of the three‐phase voltages. Main contribution of this study is the real‐time detection and classification of different PQ disturbances which even a layman can understand through visual displays to ascertain the quality of supply, unlike other PQ analysers available commercially that require some technical expertise.
Soft‐sensor approach for measuring pulverised coal flow
Authors: Naha Arunava , Deb Alok Kanti
Published: June 2014

This study presents a methodology to estimate the instantaneous pulverised coal flow rate of the E‐type vertical spindle coal mills. Modifications over a six‐segment coal mill model have been proposed, and particle swarm optimisation technique with Kalman correction has been used to optimise the unknown parameters of the modified model by using real plant data. To account for the deviation of the mill parameters with time, an extended Kalman filter (EKF) using the modified model with the optimised parameters has been implemented that updates the pulverised coal flow rate to reflect the actual evolving measurements.
The excitonic effects in single and double-walled boron nitride nanotubes
Authors: Wang Shudong , Li Yunhai , Yip Joanne , Wang Jinlan
Published: June 2014

The electronic structures and excitonic optical properties of single- and double-walled armchair boron nitride nanotubes (BNNTs) [e.g., (5,5) and (10,10), and (5,5)@(10,10)] are investigated within many-body Green's function and Bethe-Salpeter equation formalism. The first absorption peak of the double-walled nanotube has almost no shift compared with the single-walled (5,5) tube due to the strong optical transition in the double-walled tube that occurs within the inner (5,5) one. Dark and semi-dark excitonic states are detected in the lower energy region, stemming from the charge transfer between inner and outer tubes in the double-walled structure. Most interestingly, the charge transfer makes the electron and the hole reside in different tubes. Moreover, the excited electrons in the double-walled BNNT are able to transfer from the outer tube to the inner one, opposite to that which has been observed in double-walled carbon nanotubes.
Bi-O covalency in PbTiO3-BiInO3 with enhanced ferroelectric properties: Synchrotron radiation diffraction and first-principles study
Authors: Wang Fangfang , Fan Longlong , Ren Yang , Chen Jun , Xing Xianran
Published: June 2014

High-TC ferroelectric (1 − x)PbTiO3-xBiInO3 shows a sustainable spontaneous polarization in tetragonal phase by amount of BiInO3 augmented. It is rare and interesting that weak ferroelectric In3+ substitution does not reduce ferroelectricity as most of BiMeO3 materials. To understand this abnormality behavior, the structure and the cation displacements are studied by means of synchrotron radiation diffraction. The cation displacements of A-site atoms and B-site atoms exhibit a coupling property. Their sustainedly increasing trend is quantitatively associated with spontaneous polarization. Moreover, the structure, the valence electron density distributions, electron localization function, and Bader analysis have been researched on the chemical bond in (1 − x)PbTiO3-xBiInO3 through first-principles calculations here. Although In atoms substitution reduces the covalency degree, this loss is offset by enhanced covalency between Bi-O bonds. The crucial role of Bi atom substitution not only contributes to enhance the covalency but also promotes the polarization.
Synthesis and characterization of 10 nm thick piezoelectric AlN films with high c-axis orientation for miniaturized nanoelectromechanical devices
Authors: Zaghloul Usama , Piazza Gianluca
Published: June 2014

The scaling of piezoelectric nanoelectromechanical systems (NEMS) is challenged by the synthesis of ultrathin and high quality piezoelectric films on very thin electrodes. We report the synthesis and characterization of the thinnest piezoelectric aluminum nitride (AlN) films (10 nm) ever deposited on ultrathin platinum layers (2–5 nm) using reactive sputtering. X-ray diffraction, high-resolution transmission electron microscopy, and fast Fourier transform analyses confirmed the proper crystal orientation, fine columnar texture, and the continuous lattice structure within individual grains in the deposited AlN nanometer thick films. The average extracted d31 piezoelectric coefficient for the synthesized films is −1.73 pC/N, which is comparable to the reported values for micron thick and highly c-axis oriented AlN films. The 10 nm AlN films were employed to demonstrate two different types of optimized piezoelectric nanoactuators. The unimorph actuators exhibit vertical displacements as large as 1.1 μm at 0.7 V for 25 μm long and 30 nm thick beams. These results have a great potential to realize miniaturized NEMS relays with extremely low voltage, high frequency resonators, and ultrasensitive sensors.
New insights on the nature of two-dimensional polarons in semiconducting polymers: Infrared absorption in poly(3-hexylthiophene)
Authors: Pochas Christopher M. , Spano Frank C.
Published: June 2014

Infrared absorption of positively charged polarons in conjugated polymer chains and π-stacked aggregates is investigated theoretically, employing a Holstein-based Hamiltonian which treats electronic coupling, electron-vibrational coupling, and disorder on equal footing. The spectra evaluated from the Hamiltonian expressed in a one- and two-particle basis set are essentially exact, insofar as the main, aromatic-quinoidal vibrational mode is treated fully nonadiabatically. Diagonal and off-diagonal (“paracrystalline”) disorder are resolved along the polymer axis (x) and the aggregate stacking axis (y). Disorder along the polymer axis selectively attenuates the x-polarized spectrum, which is dominated by the polaron peak P1. Disorder along the stacking axis selectively attenuates the y-polarized spectrum, which is dominated by the lower-energy charge-transfer peak, DP1. Calculated spectra are in excellent agreement with the measured induced-absorption and charge-modulation spectra, reproducing the peak positions and relative peak intensities within a line shape rich in vibronic structure. Our nonadiabatic approach predicts the existence of a weak, x-polarized peak P0, slightly blueshifted from DP1. The peak is intrinsic to single polymer chains and appears in a region of the spectrum where narrow infrared active vibrational modes have been observed in nonaggregated conjugated polymers. The polaron responsible for P0 is composed mainly of two-particle wave functions and cannot be accounted for in the more conventional adiabatic treatments.
The dynamics of open precipitation tubes
Authors: Kaminker V. , Maselko J. , Pantaleone J.
Published: June 2014

When a flowing fluid is channeled by chemical or physical precipitation, then tubular structures form. These patterns are common in nature, however, there have been few quantitative studies of their formation. Here, we report measurements of the radius, length, and internal pressure, as functions of time and flow rate, for precipitation tubes growing in chemical gardens. Using these measurements we develop models for how single tubes grow and also for how multiple tubes interact with each other. In particular, when multiple tubes grow from the same source they compete for resources; short/wide tubes have less resistance to flow, and so consume more of the resources, “killing” the growth of long/narrow tubes. These tube interactions are described by an equation similar to an unstable logistic equation.
Resonant scattering of surface plasmon polaritons by dressed quantum dots
Authors: Huang Danhong , Easter Michelle , Gumbs Godfrey , Maradudin A. A. , Lin Shawn-Yu , Cardimona Dave , Zhang Xiang
Published: June 2014

The resonant scattering of surface plasmon-polariton waves (SPP) by embedded semiconductor quantum dots above the dielectric/metal interface is explored in the strong-coupling regime. In contrast to non-resonant scattering by a localized dielectric surface defect, a strong resonant peak in the spectrum of the scattered field is predicted that is accompanied by two side valleys. The peak height depends nonlinearly on the amplitude of SPP waves, reflecting the feedback dynamics from a photon-dressed electron-hole plasma inside the quantum dots. This unique behavior in the scattered field peak strength is correlated with the occurrence of a resonant dip in the absorption spectrum of SPP waves due to the interband photon-dressing effect. Our result on the scattering of SPP waves may be experimentally observable and applied to spatially selective illumination and imaging of individual molecules.
Generation of mirage effect by heated carbon nanotube thin film
Authors: Tong L. H. , Lim C. W. , Li Y. C. , Zhang Chuanzeng , Quoc Bui Tinh
Published: June 2014

Mirage effect, a common phenomenon in nature, is a naturally occurring optical phenomenon in which lights are bent due to the gradient variation of refraction in the temperature gradient medium. The theoretical analysis of mirage effect generated by heated carbon nanotube thin film is presented both for gas and liquid. Excellent agreement is demonstrated through comparing the theoretical prediction with published experimental results. It is concluded from the theoretical prediction and experimental observation that the mirage effect is more likely to happen in liquid. The phase of deflected optical beam is also discussed and the method for measurement of thermal diffusivity of medium is theoretically verified. Furthermore, a method for measuring the refractive index of gas by detecting optical beam deflection is also presented in this paper.
Electrical and photovoltaic properties of CdTe/ZnTe n-i-p junctions grown by molecular beam epitaxy
Authors: Zielony E. , Olender K. , Płaczek-Popko E. , Wosiński T. , Racino A. , Gumienny Z. , Karczewski G. , Chusnutdinow S.
Published: June 2014

Preliminary studies have been performed on photoelectrical properties of CdTe/ZnTe n-i-p junctions grown using the molecular beam epitaxy technique. Photovoltaic properties of the cells have been investigated by the measurements of current-voltage (I-V) characteristics under 1-sun illumination. I-V characteristics yield efficiencies of the cells varying from 3.4% to 4.9%. The low efficiency can be due to the presence of electrically active defects. In order to study the origin of defects in CdTe/ZnTe photovoltaic junctions, space charge techniques (C-V and deep level transient spectroscopy (DLTS)) have been applied. From the C-V measurements, a doping profile was calculated confirming charge accumulation in the i-CdTe layer. The results of the DLTS studies revealed the presence of four traps within a temperature range from 77–420 K. Three of them with activation energies equal to 0.22 eV, 0.45 eV, and 0.78 eV have been ascribed to the hole traps present in the i-CdTe material and their possible origin has been discussed. The fourth, high-temperature DLTS peak observed at ∼350 K has been attributed to extended defects as its amplitude and temperature position depends on the value of the filling pulse width. It is assumed that the defects related to the trap are either located in the i-CdTe layer or at the i-CdTe/ZnTe interface. However, it was found that the trap exhibits twofold nature: it behaves as a majority or as a minority trap, depending on the filling pulse height, which is a characteristic feature of recombination centers. This trap is presumably responsible for the low efficiency of the cells.
Generalized space and linear momentum operators in quantum mechanics
Authors: da Costa Bruno G. , Borges Ernesto P.
Published: June 2014

We propose a modification of a recently introduced generalized translation operator, by including a q-exponential factor, which implies in the definition of a Hermitian deformed linear momentum operator \documentclass[12pt]{minimal}\begin{document}$\hat{p}_q$\end{document}p̂q, and its canonically conjugate deformed position operator \documentclass[12pt]{minimal}\begin{document}$\hat{x}_q$\end{document}x̂q. A canonical transformation leads the Hamiltonian of a position-dependent mass particle to another Hamiltonian of a particle with constant mass in a conservative force field of a deformed phase space. The equation of motion for the classical phase space may be expressed in terms of the generalized dual q-derivative. A position-dependent mass confined in an infinite square potential well is shown as an instance. Uncertainty and correspondence principles are analyzed.
Multiplicity and concentration of solutions for a quasilinear Choquard equation
Authors: Alves Claudianor O. , Yang Minbo
Published: June 2014

In this paper, we study a quasilinear Choquard equation involving the p-laplacian operator and a potential function V. Under suitable assumptions on V and the nonlinearity, we prove the existence, multiplicity, and concentration of solutions for the equation by variational methods.
Local observability of state variables and parameters in nonlinear modeling quantified by delay reconstruction
Authors: Parlitz Ulrich , Schumann-Bischoff Jan , Luther Stefan
Published: June 2014

Features of the Jacobian matrix of the delay coordinates map are exploited for quantifying the robustness and reliability of state and parameter estimations for a given dynamical model using a measured time series. Relevant concepts of this approach are introduced and illustrated for discrete and continuous time systems employing a filtered Hénon map and a Rössler system.
Investigations of stacking fault density in perpendicular recording media
Authors: Piramanayagam S. N. , Varghese Binni , Yang Yi , Kiat Lee Wee , Khume Tan Hang
Published: June 2014

In magnetic recording media, the grains or clusters reverse their magnetization over a range of reversal field, resulting in a switching field distribution. In order to achieve high areal densities, it is desirable to understand and minimize such a distribution. Clusters of grains which contain stacking faults (SF) or fcc phase have lower anisotropy, an order lower than those without them. It is believed that such low anisotropy regions reverse their magnetization at a much lower reversal field than the rest of the material with a larger anisotropy. Such clusters/grains cause recording performance deterioration, such as adjacent track erasure and dc noise. Therefore, the observation of clusters that reverse at very low reversal fields (nucleation sites, NS) could give information on the noise and the adjacent track erasure. Potentially, the observed clusters could also provide information on the SF. In this paper, we study the reversal of nucleation sites in granular perpendicular media based on a magnetic force microscope (MFM) methodology and validate the observations with high resolution cross-section transmission electron microscopy (HRTEM) measurements. Samples, wherein a high anisotropy CoPt layer was introduced to control the NS or SF in a systematic way, were evaluated by MFM, TEM, and magnetometry. The magnetic properties indicated that the thickness of the CoPt layer results in an increase of nucleation sites. TEM measurements indicated a correlation between the thickness of CoPt layer and the stacking fault density. A clear correlation was also observed between the MFM results, TEM observations, and the coercivity and nucleation field of the samples, validating the effectiveness of the proposed method in evaluating the nucleation sites which potentially arise from stacking faults.
Phonon dispersion and quantization tuning of strained carbon nanotubes for flexible electronics
Authors: Gautreau Pierre , Ragab Tarek , Chu Yanbiao , Basaran Cemal
Published: June 2014

Graphene and carbon nanotubes are materials with large potentials for applications in flexible electronics. Such devices require a high level of sustainable strain and an understanding of the materials electrical properties under strain. Using supercell theory in conjunction with a comprehensive molecular mechanics model, the full band phonon dispersion of carbon nanotubes under uniaxial strain is studied. The results suggest an overall phonon softening and open up the possibility of phonon quantization tuning with uniaxial strain. The change in phonon quantization and the resulting increase in electron-phonon and phonon-phonon scattering rates offer further explanation and theoretical basis to the experimental observation of electrical properties degradation for carbon nanotubes under uniaxial strain.
Effects of surface roughening on the mass transport and mechanical properties of ionic polymer-metal composite
Authors: Chang Longfei , Asaka Kinji , Zhu Zicai , Wang Yanjie , Chen Hualing , Li Dichen
Published: June 2014

Ionic Polymer-Metal Composite (IPMC) has been well-documented of being a promising functional material in extensive applications. In its most popular and traditional manufacturing technique, roughening is a key process to ensure a satisfying performance. In this paper, based on a lately established multi-physical model, the effect of roughening process on the inner mass transportation and the electro-active output of IPMC were investigated. In the model, the electro-chemical field was monitored by Poisson equation and a properly simplified Nernst–Planck equation set, while the mechanical field was evaluated on the basis of volume strain effect. Furthermore, with Ramo-Shockley theorem, the out-circuit current and accumulated charge on the electrode were bridged with the inner cation distribution. Besides, nominal current and charge density as well as the curvature of the deformation were evaluated to characterize the performance of IPMC. The simulation was implemented by Finite Element Method with Comsol Multi-physics, based on two groups of geometrical models, those with various rough interface and those with different thickness. The results of how the roughening impact influences on the performance of IPMC were discussed progressively in three aspects, steady-state distribution of local potential and mass concentration, current response and charge accumulation, as well as the curvature of deformation. Detailed explanations for the performance improvement resulted from surface roughening were provided from the micro-distribution point of view, which can be further explored for the process optimization of IPMC.
The atomic structure and chemistry of Fe-rich steps on antiphase boundaries in Ti-doped Bi0.9Nd0.15FeO3
Authors: MacLaren Ian , Wang LiQiu , Craven Alan J. , Ramasse Quentin M. , Schaffer Bernhard , Kalantari Kambiz , Reaney Ian M.
Published: June 2014

Stepped antiphase boundaries are frequently observed in Ti-doped Bi0.85Nd0.15FeO3, related to the novel planar antiphase boundaries reported recently. The atomic structure and chemistry of these steps are determined by a combination of high angle annular dark field and bright field scanning transmission electron microscopy imaging, together with electron energy loss spectroscopy. The core of these steps is found to consist of 4 edge-sharing FeO6 octahedra. The structure is confirmed by image simulations using a frozen phonon multislice approach. The steps are also found to be negatively charged and, like the planar boundaries studied previously, result in polarisation of the surrounding perovskite matrix.
Radio-frequency sheaths physics: Experimental characterization on Tore Supra and related self-consistent modeling
Authors: Jacquot Jonathan , Milanesio Daniele , Colas Laurent , Corre Yann , Goniche Marc , Gunn Jamie , Heuraux Stéphane , Kubič Martin
Published: June 2014

During the 2011 experimental campaign, one of the three ion cyclotron resonance heating (ICRH) antennas in the Tore Supra tokamak was equipped with a new type of Faraday screen (FS). The new design aimed at minimizing the integrated parallel electric field over long field lines as well as increasing the heat exhaust capability of the actively cooled screen. It proved to be inefficient for attenuating the radio-frequency (RF)-sheaths on the screen itself on the contrary to the heat exhaust concept that allowed operation despite higher heat fluxes on the antenna. In parallel, a new approach has been proposed to model self-consistently RF sheaths: the SSWICH (Self-consistent Sheaths and Waves for IC Heating) code. Simulations results from SSWICH coupled with the TOPICA antenna code were able to reproduce the difference between the two FS designs and part of the spatial pattern of heat loads and Langmuir probe floating potential. The poloidal pattern is a reliable result that mainly depends on the electrical design of the antenna while the radial pattern is on the contrary highly sensitive to loosely constrained parameters such as perpendicular conductivity that generates a DC current circulation from the private region inside the antenna limiters to the free scrape off layer outside these limiters. Moreover, the cantilevered bars seem to be the element in the screen design that enhanced the plasma potential.
Experimental surface plasmon resonance modulated radially sheared interference imaging using a birefringent lens
Authors: Bera Mahua , Banerjee Jayeta , Ray Mina
Published: June 2014

Experimental investigation on surface plasmon resonance (SPR) modulated interference has been proposed and demonstrated under radially sheared environment with the help of a birefringent lens. SPR modulated interference images captured by a charged couple device have been demonstrated in two different analyzing regime, namely, using an analyzer and using a Wollaston prism, the later being advantageous for the simultaneous observation of p- and s-polarized contribution towards SPR. We also report the analysis of the interference imaging for the two substrate materials and also for the two analytes in order to show the substrate-sample dependency of SPR. Moreover, phase dependent resonant behavior, together with the analysis of amplitude reflection co-efficient in complex plane, has been theoretically simulated and discussed in support of the present experimental investigation, which can be well utilized for biological and chemical sensing.
Spatial frequency heterodyne imaging in the soft x-ray water window
Authors: Brůža P. , Pánek D. , Vrbová M. , Fidler V. , Rose-Petruck C.
Published: June 2014

An x-ray imaging modality called Spatial Frequency Heterodyne Imaging (SFHI) is applied in the soft x-ray water window. SFHI permits the computational decomposition of the images acquired with a single-shot exposure into an x-ray absorption image and into two image pairs formed exclusively by x-rays scattered and refracted normally to the orientation of the grid wires. In the experiments, a laser-driven plasma soft x-ray source is used in an imaging setup consisting of a linear arrangement of source, object, a metal grid, and an image detector. Theoretical simulations and experimental results are found to be in a good agreement. SFHI is demonstrated to deliver more detailed sample information than conventional x-ray absorption imaging.
Thermomechanical response of a semicrystalline polymer in the vicinity of the melting by using microcantilever technology
Authors: Soccio M. , Luongo G. , Esteves C. , Salvador-Matar A. , Ahumada O. , Rueda D. R. , García-Gutiérrez M. C. , Lotti N. , Munari A. , Ezquerra T. A.
Published: June 2014

The melting transition of a model semicrystalline polymer has been detected by the microcantilever deflection as a function of temperature. Deflection measurements were done on arrays of 8-cantilevers spin coated with the semicrystalline polymer: poly (propylene azelate). The melting of the polymer has been corroborated by grazing incidence wide angle x-ray scattering experiments performed with synchrotron radiation over a single cantilever.
Curvature induced chirality symmetry breaking in vortex core switching phenomena
Authors: Sloika Mykola I. , Kravchuk Volodymyr P. , Sheka Denis D. , Gaididei Yuri
Published: June 2014

The interplay between magnetic vortex polarity, chirality, and the curvature of the underlying surface results in a dependence of the vortex polarity switching efficiency on the vortex chirality. The switching is studied numerically by applying a short Gauss pulse of the external magnetic field to a spherical cap within its cut plane. The minimum field intensity required for the switching essentially depends on the vortex chirality and it does not depend on the initial vortex polarity. This effect decreases with the curvature radius increasing and it vanishes in the planar limit.
A comparison between semi-spheroid- and dome-shaped quantum dots coupled to wetting layer
Authors: Shahzadeh Mohammadreza , Sabaeian Mohammad
Published: June 2014

During the epitaxial growth method, self-assembled semi-spheroid-shaped quantum dots (QDs) are formed on the wetting layer (WL). However for sake of simplicity, researchers sometimes assume semi-spheroid-shaped QDs to be dome-shaped (hemisphere). In this work, a detailed and comprehensive study on the difference between electronic and transition properties of dome- and semi-spheroid-shaped quantum dots is presented. We will explain why the P-to-S intersubband transition behaves the way it does. The calculated results for intersubband P-to-S transition properties of quantum dots show two different trends for dome-shaped and semi-spheroid-shaped quantum dots. The results are interpreted using the probability of finding electron inside the dome/spheroid region, with emphasis on the effects of wetting layer. It is shown that dome-shaped and semi-spheroid-shaped quantum dots feature different electronic and transition properties, arising from the difference in lateral dimensions between dome- and semi-spheroid-shaped QDs. Moreover, an analogy is presented between the bound S-states in the quantum dots and a simple 3D quantum mechanical particle in a box, and effective sizes are calculated. The results of this work will benefit researchers to present more realistic models of coupled QD/WL systems and explain their properties more precisely.
Water-quality issues in Ramsar wetlands
Authors: Verhoeven Jos T. A.
Published: June 2014

Wetland water chemistry, i.e. the concentrations of macro ions in the water, encompasses an important component of the ecological character of a wetland. Of these ions, nutrients play a very active role because they are exchanged between living organisms and the environment via cycling processes involving plants, animals and microbes in the ecosystem. Because many wetlands in agricultural or densely populated parts of the earth are subject to enlarged nutrient inputs, their ecological character may be affected. At the same time, nutrients are processed and retained from the through-flowing water. The present article summarises these aspects of water quality in wetlands and reflects on the development of guidance for managers of wetlands listed as internationally important under the Ramsar Convention. Protection of the water-chemistry characteristics as part of the ecological character of the wetland, consequences of nutrient loading and opportunities for nutrient retention and their limitations are critically evaluated.
Contribution of L-band SAR to systematic global mangrove monitoring
Authors: Lucas Richard , Rebelo Lisa-Maria , Fatoyinbo Lola , Rosenqvist Ake , Itoh Takuya , Shimada Masanobu , Simard Marc , Souza-Filho Pedro Walfir , Thomas Nathan , Trettin Carl , Accad Arnon , Carreiras Joao , Hilarides Lammert
Published: June 2014

Information on the status of and changes in mangroves is required for national and international policy development, implementation and evaluation. To support these requirements, a component of the Japan Aerospace Exploration Agency’s (JAXA) Kyoto and Carbon (K&C) initiative has been to design and develop capability for a Global Mangrove Watch (GMW) that routinely monitors and reports on local to global changes in the extent of mangroves, primarily on the basis of observations by Japanese L-band synthetic aperture radar (SAR). The GMW aims are as follows: (1) to map progression of change within or from existing (e.g. Landsat-derived) global baselines of the extent of mangroves by comparing advanced land-observing satellite 2 (ALOS-2) phased array L-band SAR 2 (PALSAR-2) data from 2014 with that acquired by the Japanese earth resources satellite (JERS-1) SAR (1992–1998) and ALOS PALSAR (2006–2011); (2) to quantify changes in the structure and associated losses and gains of carbon on the basis of canopy height and above-ground biomass (AGB) estimated from the shuttle radar topographic mission (SRTM; acquired 2000), the ice, cloud and land-elevation satellite (ICESAT) geoscience laser altimeter system (GLAS; 2003–2010) and L-band backscatter data; (3) to determine likely losses and gains of tree species diversity through reference to International Union for the Conservation of Nature (IUCN) global thematic layers on the distribution of mangrove species; and (4) to validate maps of changes in the extent of mangroves, primarily through comparison with dense time-series of Landsat sensor data and to use these same data to describe the causes and consequences of change. The paper outlines and justifies the techniques being implemented and the role that the GMW might play in supporting national and international policies that relate specifically to the long-term conservation of mangrove ecosystems and the services they provide to society.
Preferential cooling of hot extremes from cropland albedo management
Authors: Davin Edouard L. , Seneviratne Sonia I. , Ciais Philippe , Olioso Albert , Wang Tao
Published: June 2014

Significance

The projected increase in warm extremes associated with climate change is a major concern for society and represents a threat to humans and ecosystems. This study shows that heat wave impacts could be attenuated locally by increasing surface albedo through crop residue management (no-till farming). This is due to an identified asymmetric impact of surface albedo change on summer temperature distribution resulting in a much stronger influence on hot extremes than on mean temperatures. This finding has important implications for the development of sustainable land management strategies and for the design of climate-engineering measures acting upon high-impact climate extremes.
Diel size distributions reveal seasonal growth dynamics of a coastal phytoplankter
Authors: Hunter-Cevera Kristen R. , Neubert Michael G. , Solow Andrew R. , Olson Robert J. , Shalapyonok Alexi , Sosik Heidi M.
Published: June 2014

Significance

Understanding changes in phytoplankton cell abundance requires estimates of division rates. These rates are difficult to obtain at the necessary time scales (daily) for extended periods with conventional methods. We show that a matrix population model combined with observed hourly cell size distributions accurately estimates division rates of both cultured and natural populations of the picocyanobacteria
Synechococcus
. This approach opens the path for novel insight into population dynamics. Application of the model to an annual cycle of
Synechococcus
observations reveals dramatic seasonality of division rates linked to temperature and that division and loss processes are tightly coupled throughout the year. These results suggest that
Synechococcus
populations may be especially sensitive to the predicted changes in ocean temperature from global climate change.
Detection of genomic variations and DNA polymorphisms and impact on analysis of meiotic recombination and genetic mapping
Authors: Qi Ji , Chen Yamao , Copenhaver Gregory P. , Ma Hong
Published: June 2014

Significance

Genetic analyses require allelic markers, which are often DNA polymorphisms and can be analyzed by using short reads from high-throughput sequencing. Therefore, accuracy in genetic studies depends on correct identification of DNA polymorphic markers, but genomic structural variants increase the complexity of allelic detection and must be carefully accounted for to avoid errors. Here, we examine potential mistakes in single-nucleotide polymorphism calling caused by structural variants and their impact on detecting meiotic recombination events. Our results demonstrate that it is crucial to examine structural variants in genetic analysis with DNA marker detection by using short reads, with implications for a wide range of genetic analyses.
Extensive sampling of basidiomycete genomes demonstrates inadequacy of the white-rot/brown-rot paradigm for wood decay fungi
Authors: Riley Robert , Salamov Asaf A. , Brown Daren W. , Nagy Laszlo G. , Floudas Dimitrios , Held Benjamin W. , Levasseur Anthony , Lombard Vincent , Morin Emmanuelle , Otillar Robert , Lindquist Erika A. , Sun Hui , LaButti Kurt M. , Schmutz Jeremy , Jabbour Dina , Luo Hong , Baker Scott E. , Pisabarro Antonio G. , Walton Jonathan D. , Blanchette Robert A. , Henrissat Bernard , Martin Francis , Cullen Dan , Hibbett David S. , Grigoriev Igor V.
Published: June 2014

Significance

Wood decay fungi have historically been characterized as either white rot, which degrade all components of plant cell walls, including lignin, or brown rot, which leave lignin largely intact. Genomic analyses have shown that white-rot species possess multiple lignin-degrading peroxidases (PODs) and expanded suites of enzymes attacking crystalline cellulose. To test the adequacy of the white/brown-rot categories, we analyzed 33 fungal genomes. Some species lack PODs, and thus resemble brown-rot fungi, but possess the cellulose-degrading apparatus typical of white-rot fungi. Moreover, they appear to degrade lignin, based on decay analyses on wood wafers. Our results indicate that the prevailing paradigm of white rot vs. brown rot does not capture the diversity of fungal wood decay mechanisms.
FAM65B is a membrane-associated protein of hair cell stereocilia required for hearing
Authors: Diaz-Horta Oscar , Subasioglu-Uzak Asli , Grati M’hamed , DeSmidt Alexandra , Foster Joseph , Cao Lei , Bademci Guney , Tokgoz-Yilmaz Suna , Duman Duygu , Cengiz F. Basak , Abad Clemer , Mittal Rahul , Blanton Susan , Liu Xue Z. , Farooq Amjad , Walz Katherina , Lu Zhongmin , Tekin Mustafa
Published: June 2014

Significance

Concerted action of thousands of proteins is required for the inner ear to convert acoustic waves into electrical signals for hearing. Many of these proteins are currently unknown. This study uses a genetic approach to identify
FAM65B
as a gene mutated in a family with sensorineural hearing loss. Characterization of FAM65B shows that it is a component of the plasma membrane of the stereocilia hair bundle, the essential organelle in which electrical signals originate in the inner ear. Thus, FAM65B is a previously unrecognized component of the inner ear that is crucial for hearing.
Role of cysteinyl leukotriene signaling in a mouse model of noise-induced cochlear injury
Authors: Park Jung-Sub , Kang Seo-Jun , Seo Mi-kyoung , Jou Ilo , Woo Hyun Goo , Park Sang Myun
Published: June 2014

Significance

Cysteinyl leukotriene signaling has been known to play an important role in inflammation, and its inhibition has been commonly performed to treat asthma and allergic rhinitis. In this study, we demonstrated that cysteinyl leukotriene signaling is involved in the pathogenesis of noise-induced cochlear injury and its inhibition by montelukast attenuated noise-induced hair cell death and hearing loss. In addition, we showed that the effects of montelukast on noise-induced hair cell death are mediated through the regulation of matrix metalloproteinase-3 expression. Accordingly, this study will be helpful for developing new therapeutic strategies for noise-induced hearing loss, and it will serve as a basis for investigating other hearing loss disorders in which leukotriene signaling is involved.
Rapid in vivo forward genetic approach for identifying axon death genes in
Drosophila
Authors: Neukomm Lukas J. , Burdett Thomas C. , Gonzalez Michael A. , Züchner Stephan , Freeman Marc R.
Published: June 2014

Significance

The elimination of neurites is a widespread event during the assembly of the nervous system, and in the mature brain after injury or in neurological disease. However, molecular pathways underlying neurite/axon degeneration in any context remain poorly defined. We have developed an in vivo genetic approach with single-axon precision in the
Drosophila
wing, allowing for the observation of the onset, progression, and clearance of axon degeneration alongside control axons. We generated genetic reagents to facilitate rapid in vivo isolation of ethyl methane sulphonate-induced mutants that are defective in axon degeneration. Additional unbiased and genome-wide forward genetic screens will provide novel potential drug targets for therapeutic intervention to prevent axonal and synaptic loss after injury or disease.
Shigella
reroutes host cell central metabolism to obtain high-flux nutrient supply for vigorous intracellular growth
Authors: Kentner David , Martano Giuseppe , Callon Morgane , Chiquet Petra , Brodmann Maj , Burton Olga , Wahlander Asa , Nanni Paolo , Delmotte Nathanaël , Grossmann Jonas , Limenitakis Julien , Schlapbach Ralph , Kiefer Patrick , Vorholt Julia A. , Hiller Sebastian , Bumann Dirk
Published: June 2014

Significance

Shigella
causes devastating bloody diarrhea. Rapid disease progression results from exceptionally fast
Shigella
growth inside human gut epithelial cells, but how
Shigella
can obtain nutrients at such high rates from its host cell has been unclear. Here, we show that infected host cells maintain normal central metabolism for energy production and host cell survival. However,
Shigella
captures the entire host metabolism output and degrades it further to acetate. This striking strategy provides
Shigella
with an abundant supply of a favorable energy source, while preserving host cell viability for prolonged exploitation. The crucial role of acetate metabolism for
Shigella
growth suggests potential new targets for antimicrobial chemotherapy.
Impact of fasting time on hepatic lipid metabolism in nutritional animal studies
Authors: Ikeda Ikuo , Metoki Kanae , Yamahira Takashi , Kato Masaki , Inoue Nao , Nagao Koji , Yanagita Teruyoshi , Shirakawa Hitoshi , Komai Michio
Published: June 2014

Many animal studies on improvement of lipid metabolism, using dietary components, fast the animals on the final day of the feeding. Although fasting has a significant impact on lipid metabolism, its time-dependent influence is not fully understood. We examined the effects of several fasting times on lipid metabolism. Rats fed with a semisynthetic diet for 2 wk were killed after 0 (9:00 am), 6 (7:00 am–1:00 pm), 9 (0:00 am–9:00 am), and 13 h (8:00 pm–9:00 am) of fasting. Compared to the 0 h group, marked reduction of liver weight and hepatic triacylglycerol content was observed in the 9 and 13 h groups. Activities of hepatic enzymes involved in fatty acid synthesis gradually decreased during fasting. In contrast, drastic time-dependent reduction of gene expression, of the enzymes, was observed. Expression of carnitine palmitoyltransferase mRNA was higher in the fasting groups than in the 0 h group. Our study showed that fasting has a significant impact on several parameters related to lipid metabolism in rat liver.