bluuebunny/crossref_metadata_2025 huggingface dataset:
Open platform, eight‐channel, portable bio‐potential and activity data logger for wearable medical device development
Authors: Cook A.J. , Gargiulo G.D. , Lehmann T. , Hamilton T.J.
Published: October 2015

The design of a wearable, portable and reconfigurable physical activity and an eight‐channel bio‐potential data logger, capable of increasing compliance by enabling customised feedback (i.e. calories expenditure and amount of physical activity) is presented while recording clinically meaningful information regarding a subject's health. Here an application of the device to the cardio‐vascular system comprising simultaneous recording of ECG and activity in both resting and under‐stress conditions is presented (clinical trials are performed under the supervision of expert cardiologists at Prince of Wales Hospital NSW, Australia). The designed device (based around the low‐power LPC1768 ARM processor and the bio‐potential front‐end ADS1298) is an open‐source one and is provided under the GPL GNU 3.0 collaborative licence.
Electric vehicle modelling and energy‐efficient routing using particle swarm optimisation
Authors: Abousleiman Rami , Rawashdeh Osamah
Published: October 2015

Vehicle routing is traditionally based on Dijkstra or Dijkstra‐like algorithms. These algorithms worked well for fossil fuel vehicles. The increase in pollution levels, government regulations, and pressure from environmental groups have caused an increase in electric vehicles (EVs) production and use. EVs are capable of regenerating energy which creates negative weights in search graphs that traditional algorithms are incapable of handling without some modifications. This study presents a model that characterises the energy consumption of an electric vehicle. Most passive and active factors are presented and applied in the formulation. The presented model is verified against 306 kilometres of driven data and proved to have 1.3% absolute error difference between the real vehicle's consumed energy versus the predicted energy consumption as generated by the model. The model is then used with a particle swarm optimisation algorithm to solve the single constraint optimisation problem of finding the most energy efficient route between 2 points on a map. Simulation and real‐world test results demonstrate savings in the energy consumption of the electric vehicle. Results showed more than 9.2% reductions in the energy consumption of the electric vehicle when driven on the developed algorithms’ suggested routes rather than the ones generated by Google Maps and MapQuest.
Design of compact wideband multi‐band and ultrawideband band pass filters based on coupled half wave resonators with reduced coupling gap
Authors: Naghar Azzedin , Aghzout Otman , Alejos Ana Vazquez , Sanchez Manuel Garcia , Essaaidi Mohamed
Published: October 2015

In this paper we propose a technique to design compact multi‐band and UWB bandpass filters based on coupled half wave resonators. The proposed design consists of the modification of a conventional parallel coupled Chebyshev bandpass filter structure by setting a very small or null coupling gap between the resonators of the center sections jointly with a very small spacing between resonators of the extremity sections. This spacing determines the performances of selected frequency bands. An ultrawideband response is accomplished by applying null spacing between all the adjacent resonators. We analysed the effect of the separation distance between the coupled lines on both the fractional bandwidth and group velocity of the filter response. The effect of the order assumed for the initial Chebyshev filter was also discussed. As an illustration of the proposed technique, we designed and measured a dual band and a tri‐band filter for the frequencies covering the WiMAX/WLAN/X system bands demonstrating an excellent performance, with a fractional bandwidth covering the 40% and 100% of the FCC bandwidth respectively. The proposed technique alleviates the fabrication accuracy requirements. The designs show an optimal improvement in terms of group velocity flatness.
Analysis of multi‐port amplifier calibration for optimal magnitude and phase error detection
Authors: Lee Han Lim , Lee Moon‐Que , Yu Jong‐Won
Published: October 2015

This study presents theoretical analysis and verification on optimal hardware platform for calibration of signal manipulation in multi‐port amplifier (MPA). Since MPA output power and isolation characteristics are strongly dependent on magnitude and relative phase balances in each array path of MPA, proper calibration technique is necessary for ideal MPA operation. Although variety of calibration methods can be considered, they can be classified into two methods from the calibration signal detection based on hardware platform point of view. That is, calibration signals for each array path in MPA can be sampled and detected before output hybrid matrix (OHM) or after OHM according to hardware setup. Since optimal signal detection for each array path is the key to ideal MPA calibration and maximised performance, this study theoretically analyses two different calibration hardware platforms detecting calibration signals. Then, the mathematically derived optimal calibration hardware setup for detecting magnitude and phase error is finally verified and concluded by simple simulation and measurement at 900 MHz Industrial, Scientific and Medical‐band (902–928 MHz).
Hybrid maximum power point tracking method with variable step size for photovoltaic systems
Authors: Hua Chih‐Chiang , Fang Yi‐Hsiung , Chen Wei‐Tze
Published: October 2015

A hybrid maximum power point tracking (MPPT) method with variable step size for photovoltaic (PV) systems is proposed. The proposed MPPT method combines a new modified fractional open‐circuit voltage (FOCV) method and the current sensorless method with auto‐modulation (CSAM) to achieve fast and accurate tracking. This method not only has fast tracking but also automatically adjusts the step size according to the conditions of PV array. A modified FOCV is designed to move the operating points fast to approach the maximum power points. Afterwards, the CSAM is used for fine tuning, thus the PV system with the proposed MPPT can produce a stable and maximum possible output power. The theoretical analysis of the proposed MPPT is provided, and the laboratory prototype was constructed based on a boost converter with only a single voltage sensor. The simulation and experimental results are presented to verify the system performance.
Commercial vehicle classification from spectrum parted linked image test‐attributed synthetic aperture radar imagery
Authors: Saville Michael A. , Saini Dalvir K. , Smith Jared
Published: October 2015

The primitive type attribute as recently reported in the spectrum parted linked image test algorithm is used for the first time in a 10‐vehicle classification experiment. Attributed scattering centres (ASCs) from wideband polarimetric synthetic aperture radar imagery are surveyed and two highly complementary sets of attributes are compared in a nearest neighbour classifier. The classifier performance for each set of attributes is shown to be over 90% with 10° sub‐apertures and 10 dB additive white Gaussian noise which had not been considered in earlier works. Using a common image formation and ASC extraction method to ensure that only the pixel attributes differed, two different sets of complementary attributes are compared under precisely the same conditions. In addition, the query sets of attributed images are formed from azimuth and elevation angles that are not in the set of training angles. The results show that the classifier performance degrades gracefully as the signal‐to‐noise ratio (SNR) decreases below 10 dB and that the sensitivity to aspect angle is nearly the same for all vehicle classes as the SNR approaches 10 dB and above. The primary limitation of the approach is the use of wide‐band, wide‐aperture, and polarimetric radar data.
Paper waves in the wind
Authors: Jia Pan , Andreotti Bruno , Claudin Philippe
Published: October 2015

A flexible sheet clamped at both ends and submitted to a permanent wind is unstable and propagates waves. Here, we experimentally study the selection of frequency and wavenumber as a function of the wind velocity. These quantities obey simple scaling laws, which are analytically derived from a linear stability analysis of the problem and which also involve a gravity-induced velocity scale. This approach allows us to collapse data obtained with sheets whose flexible rigidity is varied by two orders of magnitude. This principle may be applied in the future for energy harvesting.
A systematic study of the isothermal crystallization of the mono-alcohol n-butanol monitored by dielectric spectroscopy
Authors: Jensen M. H. , Alba-Simionesco C. , Niss K. , Hecksher T.
Published: October 2015

Isothermal crystallization of the mono-hydroxyl alcohol n-butanol was studied with dielectric spectroscopy in real time. The crystallization was carried out using two different sample cells at 15 temperatures between 120 K and 134 K. Crystallization is characterized by a decrease of the dielectric intensity. In addition, a shift in relaxation times to shorter times was observed during the crystallization process for all studied temperatures. The two different sample environments induced quite different crystallization behaviors, consistent and reproducible over all studied temperatures. An explanation for the difference was proposed on the background of an Avrami analysis and a Maxwell-Wagner analysis. Both types of analysis suggest that the morphology of the crystal growth changes from a higher dimension to a lower at a point during the crystallization. More generally, we conclude that a microscopic interpretation of crystallization measurements requires multiple probes, sample cells, and protocols.
On coarse projective integration for atomic deposition in amorphous systems
Authors: Chuang Claire Y. , Han Sang M. , Zepeda-Ruiz Luis A. , Sinno Talid
Published: October 2015

Direct molecular dynamics simulation of atomic deposition under realistic conditions is notoriously challenging because of the wide range of time scales that must be captured. Numerous simulation approaches have been proposed to address the problem, often requiring a compromise between model fidelity, algorithmic complexity, and computational efficiency. Coarse projective integration, an example application of the “equation-free” framework, offers an attractive balance between these constraints. Here, periodically applied, short atomistic simulations are employed to compute time derivatives of slowly evolving coarse variables that are then used to numerically integrate differential equations over relatively large time intervals. A key obstacle to the application of this technique in realistic settings is the “lifting” operation in which a valid atomistic configuration is recreated from knowledge of the coarse variables. Using Ge deposition on amorphous SiO2 substrates as an example application, we present a scheme for lifting realistic atomistic configurations comprised of collections of Ge islands on amorphous SiO2 using only a few measures of the island size distribution. The approach is shown to provide accurate initial configurations to restart molecular dynamics simulations at arbitrary points in time, enabling the application of coarse projective integration for this morphologically complex system.
Porous silicon-VO2 based hybrids as possible optical temperature sensor: Wavelength-dependent optical switching from visible to near-infrared range
Authors: Antunez E. E. , Salazar-Kuri U. , Estevez J. O. , Campos J. , Basurto M. A. , Jiménez Sandoval S. , Agarwal V.
Published: October 2015

Morphological properties of thermochromic VO2—porous silicon based hybrids reveal the growth of well-crystalized nanometer-scale features of VO2 as compared with typical submicron granular structure obtained in thin films deposited on flat substrates. Structural characterization performed as a function of temperature via grazing incidence X-ray diffraction and micro-Raman demonstrate reversible semiconductor-metal transition of the hybrid, changing from a low-temperature monoclinic VO2(M) to a high-temperature tetragonal rutile VO2(R) crystalline structure, coupled with a decrease in phase transition temperature. Effective optical response studied in terms of red/blue shift of the reflectance spectra results in a wavelength-dependent optical switching with temperature. As compared to VO2 film over crystalline silicon substrate, the hybrid structure is found to demonstrate up to 3-fold increase in the change of reflectivity with temperature, an enlarged hysteresis loop and a wider operational window for its potential application as an optical temperature sensor. Such silicon based hybrids represent an exciting class of functional materials to display thermally triggered optical switching culminated by the characteristics of each of the constituent blocks as well as device compatibility with standard integrated circuit technology.
The effects of magnetic field in plume region on the performance of multi-cusped field thruster
Authors: Hu Peng , Liu Hui , Mao Wei , Yu Daren , Gao Yuanyuan
Published: October 2015

The performance characteristics of a Multi-cusped Field Thruster depending on the magnetic field in the plume region were investigated. Five magnetic field shielding rings were separately mounted near the exit of discharge channel to decrease the strength of magnetic field in the plume region in different levels, while the magnetic field in the upstream was well maintained. The test results show that the electron current increases with the decrease of magnetic field strength in the plume region, which gives rise to higher propellant utilization and lower current utilization. On the other hand, the stronger magnetic field in the plume region improves the performance at low voltages (high current mode) while lower magnetic field improves the performance at high voltages (low current mode). This work can provide some optimal design ideas of the magnetic strength in the plume region to improve the performance of thruster.
On cooperative effects and aggregation of GNNQQNY and NNQQNY peptides
Authors: Nochebuena Jorge , Ireta Joel
Published: October 2015

Some health disturbances like neurodegenerative diseases are associated to the presence of amyloids. GNNQQNY and NNQQNY peptides are considered as prototypical examples for studying the formation of amyloids. These exhibit quite different aggregation behaviors despite they solely differ in size by one residue. To get insight into the reasons for such difference, we have examined association energies of aggregates (parallel β-sheets, fibril-spines, and crystal structures) from GNNQQNY and NNQQY using density functional theory. As we found that GNNQQNY tends to form a zwitterion in the crystal structure, we have investigated the energetics of parallel β-sheets and fibril-spines in the canonical and zwitterionic states. We found that the formation of GNNQQNY aggregates is energetically more favored than the formation of the NNQQNY ones. We show that the latter is connected to the network of hydrogen bonds formed by each aggregate. Moreover, we found that the formation of some NNQQNY aggregates is anticooperative, whereas cooperative with GNNQQNY. These results have interesting implications for deciphering the factors determining peptide aggregation propensities.
Embedded Ge nanocrystals in SiO2 synthesized by ion implantation
Authors: Baranwal V. , Gerlach J. W. , Lotnyk A. , Rauschenbach B. , Karl H. , Ojha S. , Avasthi D. K. , Kanjilal D. , Pandey Avinash C.
Published: October 2015

200 nm thick SiO2 layers grown on Si substrates were implanted with 150 keV Ge ions at three different fluences. As-implanted samples were characterized with time-of-flight secondary ion mass spectrometry and Rutherford backscattering spectrometry to obtain depth profiles and concentration of Ge ions. As-implanted samples were annealed at 950 °C for 30 min. Crystalline quality of pristine, as-implanted, and annealed samples was investigated using Raman scattering measurements and the results were compared. Crystalline structure of as-implanted and annealed samples of embedded Ge into SiO2 matrix was studied using x-ray diffraction. No secondary phase or alloy formation of Ge was detected with x-ray diffraction or Raman measurements. Scanning transmission electron microscope measurements were done to get the nanocrystal size and localized information. The results confirmed that fluence dependent Ge nanocrystals of different sizes are formed in the annealed samples. It is also observed that Ge is slowly diffusing deeper into the substrate with annealing.
Pressure effect on the zero-phonon line emission of Mn4+ in K2SiF6
Authors: Lazarowska A. , Mahlik S. , Grinberg M. , Lin Chun Che , Liu Ru-Shi
Published: October 2015

In this work, effects of pressure and temperature on the luminescent properties of the K2SiF6:Mn4+ system have been presented. At ambient pressure, the luminescent spectrum of Mn4+ consists of several lines at 610-650 nm attributed to phonon repetitions of the 2Eg → 4A2g transition and does not contain the zero phonon line (ZPL). At pressure above 9 kbar, an additional line at about 624 nm occurs, which can be attributed to the ZPL of the 2Eg → 4A2g transition in the Mn4+ ions. This change in the emission spectra is accompanied by shortening of the luminescence decay time. Further increasing pressure up to 220 kbar causes the red shift of all emission lines. Upon releasing pressure, all observed lines are going back to their previous positions. The ZPL remains visible even at ambient pressure. Taking into account XRD and Raman spectra at ambient pressure before and after compression-decompression, we have attributed these changes to pressure-induced local structure change of MnF62− octahedron.
Ab initio and atomistic simulation of local structure and defect segregation on the tilt grain boundaries in silicon
Authors: Lazebnykh Vitaly Yu. , Mysovsky Andrey S.
Published: October 2015

This paper reports the results of atomistic and ab initio simulation of several different tilt grain boundaries in silicon. The boundary structures obtained with genetic algorithm turned out to have no coordination defects, i.e., all silicon atoms restored their tetrahedral coordination during the structure optimisation. That concerns previously known symmetric Σ5 (130), Σ3 (211), and Σ29 (520) boundaries and previously unknown asymmetric Σ9 (2¯55)/(2¯11), Σ3 (2¯55)/(211), and Σ13 (790)/(3 11 0) structures. An extensive study has been performed on defect segregation on the boundaries, including neutral vacancy and carbon, phosphorus, and boron impurities. A clear correlation has been revealed between the segregation energy of the defect and local geometry of the boundary site where the defect is segregated. The authors propose a simple purely geometric model for evaluating approximate segregation energies of the listed defects.
Polarization of Balmer alpha radiation resulting from H++H collisions in Debye plasmas
Authors: Jakimovski D. , Janev R. K.
Published: October 2015

The linear polarization degree of Balmer alpha radiation resulting from H++H(1s) collisions in a hot, dense weakly coupled plasma is studied in the energy range 1–140 keV/u by adopting the Debye-Hückel potential to represent the screened interaction between charged plasma particles. Due to the energy splitting of nl hydrogen states in the short range Debye-Huckel potential, the Balmer alpha radiation contains three components corresponding to 3s-2p, 3p-2s, and 3d-2p transitions, of which only the last two can be linearly polarized. For calculation of 3lm excitation and electron capture cross sections, the two-center expansion atomic orbital close coupling method is used for a number of Debye screening lengths. The effects of plasma screening on the 3lm cross sections are manifested in significant changes of their magnitudes and energy behavior with respect to the ones in the unscreened case, producing significant changes in the polarization degree of Balmer 3p-2s and 3d-2p lines.
Algorithm 1: Three-Point Rational Function Interpolation for Calibrating Gravity Models
Authors: Williams I N , Baxter R S
Published: October 2015

Language. Subroutine MCRFI1 is written in ANSI Fortran
Spatial Pricing in Interdependent Markets: Testing Assumptions and Modeling Price Variation. A Case Study of Gasoline Retailing in St Cloud, Minnesota
Authors: Plummer P , Haining R , Sheppard E
Published: October 2015

In this paper we present an empirical evaluation of assumptions about consumer purchasing behavior for gasoline. Previous research has developed a theoretical model of spatial pricing in oligopolistically competitive markets in which it is hypothesized that retail prices vary because of both consumer price sensitivity and the choice sets available to consumers as well as awareness of prices at competing locations. With the use of household survey data collected from St Cloud, Minnesota we evaluate the plausibility of these assumptions, finding evidence to support the consumer purchasing behavior assumed in the theoretical model. By means of a spatial time series of gasoline price data for the same metropolitan area, we develop an empirical model of spatial price variation that incorporates some of the hypotheses of the original model. The results suggest support for the proposition that spatial price variations depend on the service characteristics of individual retailers and the accessibility or locational advantage of individual gasoline stations within the spatial configuration of the urban market. There also is empirical support for the conjecture that those sites which are more accessible, have larger choice sets, and charge lower prices tend to be those which attract the most sales from other retailers.
Mitigating Conflict and Violence in African Cities
Authors: Fox Sean , Beall Jo
Published: October 2015

The process of urbanisation has historically been associated with both socioeconomic development and social strain. Although there is little evidence that urbanisation per se increases the likelihood of conflict or violence in a country, in recent decades Africa has experienced exceptional rates of urban population growth in a context of economic stagnation and poor governance, producing conditions conducive to social unrest and violence. In order to improve urban security in the years ahead, the underlying risk factors must be addressed, including urban poverty, inequality, and fragile political institutions. This, in turn, requires improving urban governance in the region by strengthening the capacity of local government institutions, addressing the complex political dynamics that impede effective urban planning and management, and cultivating integrated development strategies that involve cooperation between various tiers and spheres of government and civil society.
New Configurational Effects on Perceived Contrast and Brightness: Second-Order White's Effects
Authors: Spehar Branka , Zaidi Qasim
Published: October 2015

Novel phenomena of perceived contrast and brightness in spatial configurations are presented, which are of the type used by White but consist exclusively of contrast variations or of combined contrast and luminance variations. As with White's effect, perceived contrast and brightness in these displays do not correspond to predictions based on low-level mechanisms of contrast and brightness induction, and it is suggested that spatial organisation influences the appearance of first-order and second-order stimuli in a similar fashion.
A Comparison of Methods for Estimating Directions in Egocentric Space
Authors: Montello Daniel R , Richardson Anthony E , Hegarty Mary , Provenza Michael
Published: October 2015

A central issue for researchers of human spatial knowledge, whether focused on perceptually guided action or cognitive-map acquisition, is knowledge of egocentric directions, directions from the body to objects and places. Several methods exist for measuring this knowledge. We compared two particularly important methods, manual pointing with a dial and whole-body rotation (body heading), under various conditions of sensory or memory access to targets. In two experiments, blindfolded body rotation resulted in the greatest variability of performance (variable error), while the manual dial resulted in greater consistent bias (constant error). The variability of performance with body rotation was no greater than that of the dial when subjects' memory loads for directions to targets was reduced by allowing them to peek at targets in between trials, point to concurrent auditory targets, or point with their eyes open. In both experiments, errors with the manual dial were greater for directions to targets that were further from the closest orthogonal axis (ahead, behind, right, left), while errors with body rotation with restricted perceptual access were greater for directions to targets that were further from an axis straight ahead of subjects. This suggests that the two methods will produce evidence of different organizational frameworks for egocentric spatial knowledge. Implications for the structures and processes that underlie egocentric spatial knowledge, and are involved in estimating directions, are discussed, as is the value of decomposing absolute errors into variable and constant errors.
Driving Experience and the Functional Field of View
Authors: Crundall David , Underwood Geoffrey , Chapman Peter
Published: October 2015

Research has suggested that novice drivers have different search strategies compared with their more experienced counterparts, and that this may contribute to their increased accident liability. One issue of concern is whether experienced drivers have a wider field of peripheral vision than less experienced drivers. This study attempted to distinguish between people of varying driving experience on the basis of their functional fields of view. Participants searched video clips taken from a moving driver's perspective for potential hazards while responding to peripheral target lights. Hit rates for peripheral targets decreased for all participant groups as processing demands increased (ie when hazards occurred) and as the eccentricity of the target increased, though there was no interaction. An effect of experience was also found which suggests that this paradigm measures a perceptual skill or strategy that develops with driving experience.
Temporal Constraints on Visual Learning: A Computational Model
Authors: Stone James V , Harper Nicol
Published: October 2015

Given a constant stream of perceptual stimuli, how can the underlying invariances associated with a given input be learned? One approach consists of using generic truths about the spatiotemporal structure of the physical world as constraints on the types of quantities learned. The learning methodology employed here embodies one such truth: that perceptually salient properties (such as stereo disparity) tend to vary smoothly over time. Unfortunately, the units of an artificial neural network tend to encode superficial image properties, such as individual grey-level pixel values, which vary rapidly over time. However, if the states of units are constrained to vary slowly, then the network is forced to learn a smoothly varying function of the training data. We implemented this temporal-smoothness constraint in a backpropagation network which learned stereo disparity from random-dot stereograms. Temporal smoothness was formalised with the use of regularisation theory by modifying the standard cost function minimised during training of a network. Temporal smoothness was found to be similar to other techniques for improving generalisation, such as early stopping and weight decay. However, in contrast to these, the theoretical underpinnings of temporal smoothing are intimately related to fundamental characteristics of the physical world. Results are discussed in terms of regularisation theory and the physically realistic assumptions upon which temporal smoothing is based.
An Analysis of Binocular Slant Contrast
Authors: van Ee Raymond , Banks Martin S , Backus Benjamin T
Published: October 2015

When a small frontoparallel surface (a test strip) is surrounded by a larger slanted surface (an inducer), the test strip is perceived as slanted in the direction opposite to the inducer. This has been called the depth-contrast effect, but we call it the slant-contrast effect. In nearly all demonstrations of this effect, the inducer's slant is specified by stereoscopic signals; and other signals, such as the texture gradient, specify that it is frontoparallel. We present a theory of slant estimation that determines surface slant via linear combination of various slant estimators; the weight of each estimator is proportional to its reliability. The theory explains slant contrast because the absolute slant of the inducer and the relative slant between test strip and inducer are both estimated with greater reliability than the absolute slant of the test strip. The theory predicts that slant contrast will be eliminated if the signals specifying the inducer's slant are consistent with one another. It also predicts reversed slant contrast if the inducer's slant is specified by nonstereoscopic signals rather than by stereo signals. These predictions were tested and confirmed in three experiments. The first showed that slant contrast is greatly reduced when the stereo-specified and nonstereo-specified slants of the inducer are made consistent with one another. The second showed that slant contrast is eliminated altogether when the stimulus consists of real planes rather than images on a display screen. The third showed that slant contrast is reversed when the nonstereo-specified slant of the inducer varies and the stereo-specified slant is zero. We conclude that slant contrast is a byproduct of the visual system's reconciliation of conflicting information while it attempts to determine surface slant.
A Multiscale Filtering Explanation of Gradient Induction and Remote Brightness Induction Effects: A Reply to Logvinenko (2003)
Authors: Blakeslee Barbara , McCourt Mark E
Published: October 2015

Grating induction is a brightness effect in which a counterphase spatial brightness variation (a grating) is induced in a homogeneous test strip that is surrounded by an inducing luminance grating (McCourt, 1982 Vision Research22 119–134). Moulden and Kingdom (1991 Vision Research31 1999–2008) introduced an interesting variant of grating induction (sometimes referred to as gradient induction) in which multiple strips of either a linear luminance ramp or a sine-wave grating were interlaced with strips of homogeneous luminance. We (Blakeslee and McCourt, 1999 Vision Research39 4361–4377) demonstrated that a simple multiscale filtering explanation could account for grating induction. Recently, however, Logvinenko (2003 Perception32 621–626) presented several arguments impugning the adequacy of spatial filtering approaches to understanding brightness induction in gradient induction stimuli. We propose that Logvinenko's arguments apply only to a limited class of filtering models, specifically those which employ only a single spatial filter. To test this hypothesis we modeled gradient induction stimuli as a function of inducing contrast, as well as Logvinenko's (2003) remote induction stimulus, using our multiscale oriented difference-of-Gaussians (ODOG) model (Blakeslee and McCourt 1999). The ODOG model successfully predicts the appearance of the inducing strips and the homogeneous test strips in the gradient induction stimuli and the appearance of the test patches in the remote induction stimuli. These results refute Logvinenko's (2003) claims, and we interpret them as providing strong evidence for a multiscale filtering approach to understanding both gradient induction and remote brightness induction effects.
How grow-and-switch gravitropism generates root coiling and root waving growth responses in
Medicago truncatula
Authors: Tan Tzer Han , Silverberg Jesse L. , Floss Daniela S. , Harrison Maria J. , Henley Christopher L. , Cohen Itai
Published: October 2015

Significance

Root waving, a growth response previously discussed predominantly in
Arabidopsis
, is reported in
Medicago truncatula
. Analogous to bacterial chemotaxis where
Escherichia coli
uses a “run-and-tumble” strategy to find sources of food, our experiments reveal a “grow-and-switch” gravitropic response in these root systems. This finding offers valuable insights into the strategies used for plants as they navigate heterogeneous environments in search of water and nutrient resources.
Control of cerebellar granule cell output by sensory-evoked Golgi cell inhibition
Authors: Duguid Ian , Branco Tiago , Chadderton Paul , Arlt Charlotte , Powell Kate , Häusser Michael
Published: October 2015

Significance

Understanding how synaptic inhibition regulates sensory responses is a fundamental question in neuroscience. In cerebellar granule cells, sensory stimulation is thought to evoke an excitation–inhibition sequence driven by direct input from mossy fibers and followed by classical disynaptic feed-forward inhibition from nearby Golgi cells. We made, to our knowledge, the first voltage-clamp recordings of sensory-evoked inhibition in granule cells in vivo and show that, surprisingly, sensory-evoked inhibition often precedes mossy fiber excitation activated by the same stimulus. We demonstrate how such “preceding” inhibition can shape granule cell responses to sensory stimulation. Our findings challenge the existing view that classical feed-forward inhibition is the dominant mode of inhibition, suggesting that parallel inhibitory networks regulate sensory information transmission through the granular layer.
Regulation of outer kinetochore Ndc80 complex-based microtubule attachments by the central kinetochore Mis12/MIND complex
Authors: Kudalkar Emily M. , Scarborough Emily A. , Umbreit Neil T. , Zelter Alex , Gestaut Daniel R. , Riffle Michael , Johnson Richard S. , MacCoss Michael J. , Asbury Charles L. , Davis Trisha N.
Published: October 2015

Significance

During cell division, multisubunit kinetochores partition chromosomes while maintaining a grip on dynamic microtubules under tension. Previous work in
Caenorhabditis elegans
showed that the central kinetochore component, Mis12/MIND (Mtw1, Nsl1, Nnf1, Dsn1) complex, increases microtubule binding of outer kinetochore complexes, but the mechanism for this enhancement remains unknown. Here, we identify new contacts between MIND and the outer kinetochore Ndc80 (Ndc80, Nuf2, Spc24, Spc25) complex that are essential for interaction in vitro and for cell viability. Using single-molecule microscopy, we demonstrate that a single MIND complex enhances the microtubule binding of a single Ndc80 complex. Our results suggest a molecular mechanism for enhancing kinetochore–microtubule attachment by a central kinetochore component.
Endothelial Bmx tyrosine kinase activity is essential for myocardial hypertrophy and remodeling
Authors: Holopainen Tanja , Räsänen Markus , Anisimov Andrey , Tuomainen Tomi , Zheng Wei , Tvorogov Denis , Hulmi Juha J. , Andersson Leif C. , Cenni Bruno , Tavi Pasi , Mervaala Eero , Kivelä Riikka , Alitalo Kari
Published: October 2015

Significance

During the last decades, heart failure has developed into a major burden in the western world, increasingly affecting millions. Cardiac hypertrophy is an adaptive response to myocardial infarction or increased blood pressure, and it often leads to heart failure. Understanding the underlying regulatory processes in the development of pathological hypertrophy is needed for the development of effective therapies. Our results show that the kinase activity of the endothelial bone marrow kinase in chromosome X (Bmx) protein is necessary for the development of pathological cardiac hypertrophy. This finding could provide significant therapeutic applications when specific Bmx kinase inhibitors become available in the clinics.
Canadian Parents for French
Authors: Gibson Judy , Roy Sylvie
Published: October 2015

This article describes the efforts undertaken by a grassroots, non-profit association established to promote French-second-language learning in Canada, and how those efforts have contributed to the advancement of Canada’s official languages policy. After identifying the historical context in which the immersion approach to second language instruction was developed, we use a historical institutionalism theory with an archival research method to examine texts produced by Canadian Parents for French over the past 38 years to see how the organization has contributed to the growth of English-French bilingualism within Canada. We then note the continuing challenges to universal access to French immersion programs which the association has identified. This article demonstrates that stakeholders can play an important role in the successful implementation of a policy and offers examples that may be relevant for international audiences seeking to promote language learning.
Saying the unsayable
Authors: Wodak Ruth
Published: October 2015

After 1945 and the end of WWII, denying the Holocaust became an explicit taboo in most European countries. More specifically, in Austria, denying the Holocaust in public implies legal consequences: the so-calledVerbotsgesetzpersecutes any public utterances which even insinuate National Socialist ideology (utterances, symbols, songs, images) and the Holocaust denial. Naturally, it remains difficult for the courts to substantiate any accusations and to prove that somebody has actually uttered Holocaust denial if the meanings are only implied, inferred, or alluded to. Thus, in spite of such explicit sanctions, politicians of the far-right have found many coded and implicit discursive-pragmatic practices and devices of denying the Holocaust, even during parliamentary debates and official speeches. In my paper, I compare the “discourses about Holocaust denial” in Austria and the UK, in two case studies: the first one relates to the controversy about some utterances of Barbara Rosenkranz who stood as candidate of the Austrian Freedom Party (FPÖ) for election to Austrian Presidency in April 2010. Secondly, I focus on the debates triggered by Nick Griffin from the British extreme right party BNP, in and after his appearance in the prominent BBC 1 weekly showQuestion Time, in 2009. I apply the Discourse-Historical Approach in CDA for the detailed analysis of such recurring debates and foreground the patterns of a globalisedpolitics of denial.
The politics of being insulted
Authors: Kampf Zohar
Published: October 2015

Scholars of politeness admit that being insulted may be the result of the hearer’s assumptions about the other’s behavior and may not necessarily relate to the actual words or intentions of the speaker. Thus, it is surprising to find only a few accounts of how people are doing “being insulted” or of how, in public discourse, responses to insults are strategically employed for various ends. In this paper, I analyze the meta-pragmatics of “hurt feelings” in order to understand how speakers do things with emotions and the role of hurt feelings in political democratic discourse. By examining instances in which public figures have stated their feelings of insult in Israeli public discourse (1997–2012), I show both how hurt feelings are strategically employed to protest against politically unacceptable acts, and how public actors sometimes explicitly refuse to be insulted, shifting the meaning of what is perceived as an insult by side-participants into a compliment. I conclude by discussing the consequences of manifesting hurt feelings in political discourse.
Representing “terrorism”
Authors: Evans Matthew , Schuller Simone
Published: October 2015

This paper uses critical stylistics to analyse the British press’s use of the term “terrorism” in their reporting of the murder of Fusilier Lee Rigby outside the military barracks in Woolwich, London on 22nd May 2013. It considers academic definitions of “terrorism” and compares these to the use of the term in newspaper reports on the attack. The authors seek to understand how the Woolwich attack is fit into a complex and contested concept such as terrorism. A close reading of a small corpus of national newspaper articles was used to identify common themes in the way the incident is portrayed, with critical stylistic analysis being applied to investigate how the term “terrorism” is used in context. The study highlights how the application of the “terrorism” label is justified within the articles despite the scarcity of information regarding the attack and persons involved at the time of their publication.
Discursive violence and responsibility
Authors: Leezenberg Michiel
Published: October 2015

This article discusses the discursive strategies of the Freedom Party (PVV), a contemporary Dutch populist and Islamophobic party. After tracing its ideological roots to mainstream liberalism rather than earlier forms of extreme right political movements, I will discuss its discourse about Muslims. It will appear that this discourse goes far beyond the legitimate expression of opinion. Using some of Judith Butler’s ideas about the performativity of hate speech, I will attempt to describe how PVV leader Geert Wilders’s language is not only a discourseaboutviolence, but is also itself a discourseofviolence. Simultaneously, however, Wilders systematically denied responsibility for any violence his words might contain, imply, or provoke; instead, he and his sympathizers blamed both Muslims and his political opponents for whatever violence might occur in the wake of his utterances. This appears most clearly in the discussion following Norwegian Anders Breivik’s murderous 2011 assault on the Utøya island, an act which he himself claimed was in part inspired by Wilders’s political rhetoric.
The coming crisis of Zuma's ANC: the party state confronts fiscal crisis
Authors: Southall Roger
Published: October 2015

Rising state expenditure threatens to outstrip the South African government's ability to pay. This danger is merely a symptom of and challenge to the predatory characteristics of the ‘party-state’ erected by the ruling African National Congress (ANC), notably as they are exhibited under the presidency of Jacob Zuma. The ANC government is increasingly looking to an oil and gas bonanza to avoid a ‘fiscal cliff’, while Zuma himself is driving a nuclear power future which threatens to bankrupt the economy. The latter strategy conforms to the party's greater disposition to corruption and patronage. Key parastatals have become headed by Zuma cronies; family and friends have been awarded government favour; and Zuma's personal interests intrude upon the governance of parastatals, the South African Revenue Service and the functioning of constitutionally protected agencies such as the office of the Public Protector. The Zuma government's repudiation of accountability highlights an official drift to secrecy. However, the increasing limitations of ANC economic policy combine with growing discontent in society to place the party's political hegemony at risk – but Zuma's presidency has compromised the ANC's capacity for internal reform.
A goose-type lysozyme from ostrich (Struthio camelus) egg white: multiple roles of His101 in its enzymatic reaction
Authors: Somboonpatarakun Chalermchai , Shinya Shoko , Kawaguchi Yuya , Araki Tomohiro , Fukamizo Tamo , Klaynongsruang Sompong
Published: October 2015

A goose-type lysozyme from ostrich egg white (OEL) was produced by Escherichia coli expression system, and the role of His101 of OEL in the enzymatic reaction was investigated by NMR spectroscopy, thermal unfolding, and theoretical modeling of the enzymatic hydrolysis of hexa-N-acetylchitohexaose, (GlcNAc)6. Although the binding of tri-N-acetylchitotriose, (GlcNAc)3, to OEL perturbed several backbone resonances in the 1H–15N HSQC spectrum, the chemical shift of the backbone resonance of His101 was not significantly affected. However, apparent pKa values of His101 and Lys102 determined from the pH titration curves of the backbone chemical shifts were markedly shifted by (GlcNAc)3 binding. Thermal unfolding experiments and modeling study of (GlcNAc)6 hydrolysis using a His101-mutated OEL (H101A-OEL) revealed that the His101 mutation affected not only sugar residue affinities at subsites −3 and −2 but also the rate constant for bond cleavage. His101 appears to play multiple roles in the substrate binding and the catalytic reaction.
cl-dash: rapid configuration and deployment of Hadoop clusters for bioinformatics research in the cloud
Authors: Hodor Paul , Chawla Amandeep , Clark Andrew , Neal Lauren
Published: October 2015

Summary: One of the solutions proposed for addressing the challenge of the overwhelming abundance of genomic sequence and other biological data is the use of the Hadoop computing framework. Appropriate tools are needed to set up computational environments that facilitate research of novel bioinformatics methodology using Hadoop. Here, we present cl-dash, a complete starter kit for setting up such an environment. Configuring and deploying new Hadoop clusters can be done in minutes. Use of Amazon Web Services ensures no initial investment and minimal operation costs. Two sample bioinformatics applications help the researcher understand and learn the principles of implementing an algorithm using the MapReduce programming pattern.

Availability and implementation: Source code is available at https://bitbucket.org/booz-allen-sci-comp-team/cl-dash.git.

Contact:  hodor_paul@bah.com
The reactivation of main-belt Comet 324P/La Sagra (P/2010 R2)
Authors: Hsieh H. H. , Sheppard S. S.
Published: October 2015

We present observations using the Baade Magellan and Canada–France–Hawaii telescopes showing that main-belt comet 324P/La Sagra, formerly known as P/2010 R2, has become active again for the first time since originally observed to be active in 2010–2011. The object appears point-source-like in 2015 March and April as it approached perihelion (true anomaly of ν ∼ 300°), but was ∼1 mag brighter than expected if inactive, suggesting the presence of unresolved dust emission. Activity was confirmed by observations of a cometary dust tail in 2015 May and June. We find an apparent net dust production rate of ${\dot{M}_{\rm d}}\lesssim 0.1$ kg s−1 during these observations. 324P is now the fourth main-belt comet confirmed to be recurrently active, a strong indication that its activity is driven by sublimation. It now has the largest confirmed active range of all likely main-belt comets, and also the most distant confirmed inbound activation point at R  ∼  2.8 au. Further observations during the current active period will allow direct comparisons of activity strength with 324P's 2010 activity.
Employing transposon mutagenesis to investigate foot-and-mouth disease virus replication
Authors: Herod Morgan R. , Loundras Eleni-Anna , Ward Joseph C. , Tulloch Fiona , Rowlands David J. , Stonehouse Nicola J.
Published: October 2015

Probing the molecular interactions within the foot-and-mouth disease virus (FMDV) RNA replication complex has been restricted in part by the lack of suitable reagents. Random insertional mutagenesis has proven an excellent method to reveal domains of proteins essential for virus replication as well as locations that can tolerate small genetic insertions. Such insertion sites can subsequently be adapted by the incorporation of commonly used epitope tags, facilitating their detection with commercially available reagents. In this study, we used random transposon-mediated mutagenesis to produce a library of 15 nt insertions in the FMDV non-structural polyprotein. Using a replicon-based assay, we isolated multiple replication-competent as well as replication-defective insertions. We adapted the replication-competent insertion sites for the successful incorporation of epitope tags within FMDV non-structural proteins for use in a variety of downstream assays. Additionally, we showed that replication of some of the replication-defective insertion mutants could be rescued by co-transfection of a ‘helper’ replicon, demonstrating a novel use of random mutagenesis to identify intergenomictrans-complementation. Both the epitope tags and replication-defective insertions identified here will be valuable tools for probing interactions within picornavirus replication complexes.