bluuebunny/crossref_metadata_2025 huggingface dataset:
Luma–chroma separated processing for fast flow‐based image abstraction on mobile devices
Authors: Kim Jin‐Woo , Jeon Se‐Weon , Han Tack‐Don
Published: November 2014

A fast method to generate cartoon‐style images is presented. The cartoon‐style image construction procedure consists of two processes: outline detection followed by colour filling. The outline detection operation is sensitive to image luminance (luma) and the colour‐filling operation is sensitive to chrominance (chroma). Using this feature, a fast method is proposed for generating cartoon‐style images based on luminance–chrominance (luma–chroma) separated processing. This method decreases the number of operations required for colour filling using a UV chroma component extracted from the YUV colour space. This approach is suitable for camera image formats and mobile SIMD units. Experimental tests demonstrate that the proposed method exhibits 221% faster processing time as compared to naïve methods. Moreover, the mean absolute error between naïve methods and the proposed method is < 1%.
Short pulse groups searching based on isomorphic sequences
Authors: Li Feng , Ren Lixiang , Cao Jun , Long Teng
Published: November 2014

Conventional pulse sorting algorithms have difficulty in extracting short pulse groups which are dispersed in massive pulse streams. An isomorphic sequence search algorithm, based on a suffix array and the longest common prefix, is used to extract short pulse repetition interval‐repeated pulse groups.
Miniaturised ultra‐wideband circularly polarised antenna with modified ground plane
Authors: Shokri M. , Rafii V. , Karamzadeh S. , Amiri Z. , Virdee B.
Published: November 2014

A unique coplanar‐waveguide (CPW)‐fed circularly polarised square slot antenna with enhanced impedance bandwidth (IBW) is presented. The antenna structure includes a pair of rectangular‐shaped notches located at two opposite corners of the slot for achieving a significantly enhanced IBW of 12.06 GHz (2.76–14.82 GHz), and a pair of reverse L‐shaped ground arms in the slot for realising circularly polarised radiation with 1.86 GHz (4.27–6.13 GHz) bandwidth. This proposed technique has the advantages of covering the whole of the ultra‐wideband spectrum (3.1–10.6 GHz), an average gain of 3 dBi and a reduced antenna size of 25 × 25 × 0.8 mm3.
Using statistical characteristics of gradient phases for robust face recognition under illumination variations
Authors: Su Ching‐Yao , Yang Jar‐Ferr
Published: November 2014

Gradient phase, which is treated as an illumination insensitive measure, is an important feature for visual detection and recognition applications, especially under illumination variations. However, fewer statistical characteristics of the gradient phase have been reported till now. First, the statistical characteristics of the gradient phase against gradient signal‐to‐noise ratios (gradient SNRs) were investigated. The analysed results show that the confidence (or standard deviation) of gradient phases against gradient SNRs should never be linearly related, as is usually supposed. With the help of the statistical analyses of the gradient phase, the gradient‐based visual detection and recognition were improved by incorporating confidence information into the cost function. Moreover, inspired by the analysed characteristics of the gradient phase, an enhanced gradientface method is proposed to improve the performance of the gradient phase‐based face recognition. Intensive simulations and comparisons are performed to show its superior performance without the side effect of discrimination loss that existed in some illumination normalisation approaches.
Simulation study of single event effects for split‐gate enhanced power U‐shape metal‐oxide semiconductor field‐effect transistor
Authors: Ying Wang , Yu Cheng‐Hao , Cao Fei , Shan Ming‐Guang
Published: November 2014

Power metal‐oxide semiconductor field‐effect transistors (MOSFETs) are increasingly used in the space probes where the environment is composed of various kinds of particles. Thus, it is essential to study the influence of the natural radiation environment on the electrical behaviour of MOSFETs in space. This study presents two‐dimensional numerical simulation results, which investigates the sensitive volume, triggering criteria and characteristics of single‐event burnout (SEB) and single‐event gate rupture (SEGR) for the split‐gate enhanced power U‐shape MOSFET (SGE‐UMOS). In addition, the comparison of the standard Trench‐UMOS and SGE‐UMOS for both SEB and SEGR simulation results is investigated. The SGE‐UMOS shows an improved SEB performance than the standard Trench‐UMOS with a larger safe operating area. The SGE‐UMOS can also contribute to protect against SEGR compared with standard Trench‐UMOS.
Parallel asymmetric pulse‐width modulation converters with same power switches for medium power applications
Authors: Lin Bor‐Ren , Chen Kuan‐Hao
Published: November 2014

A new zero‐voltage switching (ZVS) half‐bridge converter with three circuit modules is presented in this study to reduce the switching losses of power switches and current stress of passive components for medium power applications. Three circuit modules with the same power switches are connected in parallel at input and output sides. Thus, the switch counts are reduced compared with the parallel half‐bridge converter with the same power rating. Each circuit module supplies one‐third of load power to output side. Owing to the half‐bridge converter leg, the voltage stress of each power switch is clamped at input DC voltage. Three centre‐tapped rectifiers are adopted at low voltage side to share load current and reduce the size of magnetic cores. Asymmetric pulse‐width modulation is adopted to regulate output voltage at the desired voltage level. Owing to the resonant behaviour by resonant capacitance [or output capacitance of metal‐oxide semiconductor field‐effect transistors (MOSFETs)] and leakage inductance (or external inductance) at the transition interval, power MOSFETs can be turned on under ZVS. The system analysis, circuit characteristics and design example of the proposed converter are discussed in detail. Finally, experiments with a 1620 W prototype are provided to verify the effectiveness of the proposed converter.
Controllable synthesis of zinc tetraphenylporphyrin microcrystals by a facile, fast and surfactant‐free process
Authors: Sun Jian , Wu Kong‐Lin , He Yue‐Zhen , Ye Yin , Wei Xian‐Wen
Published: November 2014

Uniform octahedral zinc tetraphenylporphyrin (ZnTPP) microcrystals were obtained in a large scale by a facile, fast and surfactant‐free process at room temperature. The effects of synthetic parameters such as solvent and concentration on the formation and morphology of ZnTPP were investigated. Furthermore, by varying the reaction time, both the morphology and the size of the ZnTPP microcrystals can be controlled.
Determination of Pb2+ ions by square‐wave anodic stripping voltammetry using silver nanoparticles grown on indium tin oxide substrate
Authors: Huang Rong Bin , Zheng Yi Fan
Published: November 2014

Silver (Ag) nanoparticles with a pure face‐centred cubic phase were grown on indium tin oxide (ITO) substrate via the electrodeposition method. The products were characterised by scanning electron microscopy, energy‐dispersive X‐ray analysis and X‐ray diffraction. Ag nanoparticles deposited on the ITO substrate were first used as an electrode for the electrochemical analysis of lead ions. A linear response was observed for Pb2+ in the range of 0.1–8 µM. The linear regression equation was I = 0.129 + 0.368C (unit of C is μM) and the correlation coefficient was 0.9993. The detection limit was 70 nM Pb2+ (S/N = 3). The results open new possibilities for the fabrication of novel electrodes for the construction of simple, low‐cost and reliable electrochemical sensors for the quantification of trace levels of Pb2+.
A compact, robust, and transportable ultra-stable laser with a fractional frequency instability of 1 × 10−15
Authors: Chen Qun-Feng , Nevsky Alexander , Cardace Marco , Schiller Stephan , Legero Thomas , Häfner Sebastian , Uhde Andre , Sterr Uwe
Published: November 2014

We present a compact and robust transportable ultra-stable laser system with minimum fractional frequency instability of 1 × 10−15 at integration times between 1 and 10 s. The system was conceived as a prototype of a subsystem of a microwave-optical local oscillator to be used on the satellite mission Space-Time Explorer and QUantum Equivalence Principle Space Test (STE-QUEST) (http://sci.esa.int/ste-quest/). It was therefore designed to be compact, to sustain accelerations occurring during rocket launch, to exhibit low vibration sensitivity, and to reach a low frequency instability. Overall dimensions of the optical system are 40 cm × 20 cm × 30 cm. The acceleration sensitivities of the optical frequency in the three directions were measured to be 1.7 × 10−11/g, 8.0 × 10−11/g, and 3.9 × 10−10/g, and the absolute frequency instability was determined via a three-cornered hat measurement. Two additional cavity-stabilized lasers were used for this purpose, one of which had an instability σy < 4 × 10−16 at 1 s integration time. The design is also appropriate and useful for terrestrial applications.
High-resolution laser spectroscopy and magnetic effect of the $\tilde B$B̃2E′ ← $\tilde X$X̃2A2′ transition of 14NO3 radical
Authors: Tada Kohei , Kashihara Wataru , Baba Masaaki , Ishiwata Takashi , Hirota Eizi , Kasahara Shunji
Published: November 2014

Rotationally resolved high-resolution fluorescence excitation spectra of 14NO3 radical have been observed for the 662 nm band, which is assigned as the 0–0 band of the $\tilde B$B̃2E′ ←$\tilde X$X̃2A2′ transition, by crossing a single-mode laser beam perpendicularly to a collimated molecular beam. More than 3000 rotational lines were detected in 15 070–15 145 cm−1 region, but it is difficult to find the rotational line series. Remarkable rotational line pairs, whose interval is about 0.0246 cm−1, were found in the observed spectrum. This interval is the same amount with the spin-rotation splitting of the $\tilde X$X̃2A2′ (υ = 0, k = 0, N = 1) level. From this interval and the observed Zeeman splitting up to 360 G, seven line pairs were assigned as the transitions to the 2E′3/2 (J′ = 1.5) levels and 15 line pairs were assigned as the transitions to the 2E′1/2 (J′ = 0.5) levels. From the rotational analysis, we recognized that the 2E′ state splits into 2E′3/2 and 2E′1/2 by the spin-orbit interaction and the effective spin-orbit interaction constant was roughly estimated as –21 cm−1. From the number of the rotational line pairs, we concluded that the complicated rotational structure of this 662 nm band of 14NO3 mainly owes to the vibronic interaction between the $\tilde B$B̃2E′ state and the dark $\tilde A$Ã2E″ state through the a2″ symmetry vibrational mode.
Spatial resolution of the electrical conductance of ionic fluids using a Green-Kubo method
Authors: Jones R. E. , Ward D. K. , Templeton J. A.
Published: November 2014

We present a Green-Kubo method to spatially resolve transport coefficients in compositionally heterogeneous mixtures. We develop the underlying theory based on well-known results from mixture theory, Irving-Kirkwood field estimation, and linear response theory. Then, using standard molecular dynamics techniques, we apply the methodology to representative systems. With a homogeneous salt water system, where the expectation of the distribution of conductivity is clear, we demonstrate the sensitivities of the method to system size, and other physical and algorithmic parameters. Then we present a simple model of an electrochemical double layer where we explore the resolution limit of the method. In this system, we observe significant anisotropy in the wall-normal vs. transverse ionic conductances, as well as near wall effects. Finally, we discuss extensions and applications to more realistic systems such as batteries where detailed understanding of the transport properties in the vicinity of the electrodes is of technological importance.
Phase diagrams of mixtures of a polymer and a cholesteric liquid crystal under an external field
Authors: Matsuyama Akihiko
Published: November 2014

We present a mean field theory to describe phase behaviors in mixtures of a polymer and a cholesteric liquid crystal under an external magnetic or electric field. Taking into account a chiral coupling between a polymer and a liquid crystal under the external field, we examine twist-untwist phase transitions and phase separations in the mixtures. It is found that a cholesteric-nematic phase transition can be induced by not only the external field but also concentration and temperature. Depending on the strength of the external field, we predict cholesteric-paranematic (Ch+pN), nematic-paranematic (N+pN), cholesteric-nematic (Ch+N) phase separations, etc., on the temperature-concentration plane. We also discuss mixtures of a non-chiral nematic liquid crystal and a chiral dopant.
Nets, tiles, and metal-organic frameworks
Authors: O’Keeffe Michael
Published: November 2014

An account is given of the basic nets that are important in the description and design of metal-organic framework (MOF) structures. These are generally of minimal transitivity, a concept which is explained. Derived nets are defined and the advantages of using derived nets to describe the topology of MOF frameworks with multiple branch points are emphasized.
Ultraviolet emission from low resistance Cu2SnS3/SnO2 and CuInS2/Sn:In2O3 nanowires
Authors: Karageorgou E. , Zervos M. , Othonos A.
Published: November 2014

SnO2 and Sn:In2O3 nanowires were grown on Si(001), and p-n junctions were fabricated in contact with p-type Cu2S which exhibited rectifying current–voltage characteristics. Core-shell Cu2SnS3/SnO2 and CuInS2/Sn:In2O3 nanowires were obtained by depositing copper and post-growth processing under H2S between 100 and 500 °C. These consist mainly of tetragonal rutile SnO2 and cubic bixbyite In2O3. We observe photoluminescence at 3.65 eV corresponding to band edge emission from SnO2 quantum dots in the Cu2SnS3/SnO2 nanowires due to electrostatic confinement. The Cu2SnS3/SnO2 nanowires assemblies had resistances of 100 Ω similar to CuInS2/In2O3 nanowires which exhibited photoluminescence at 3.0 eV.
Quantum, classical, and hybrid QM/MM calculations in solution: General implementation of the ddCOSMO linear scaling strategy
Authors: Lipparini Filippo , Scalmani Giovanni , Lagardère Louis , Stamm Benjamin , Cancès Eric , Maday Yvon , Piquemal Jean-Philip , Frisch Michael J. , Mennucci Benedetta
Published: November 2014

We present the general theory and implementation of the Conductor-like Screening Model according to the recently developed ddCOSMO paradigm. The various quantities needed to apply ddCOSMO at different levels of theory, including quantum mechanical descriptions, are discussed in detail, with a particular focus on how to compute the integrals needed to evaluate the ddCOSMO solvation energy and its derivatives. The overall computational cost of a ddCOSMO computation is then analyzed and decomposed in the various steps: the different relative weights of such contributions are then discussed for both ddCOSMO and the fastest available alternative discretization to the COSMO equations. Finally, the scaling of the cost of the various steps with respect to the size of the solute is analyzed and discussed, showing how ddCOSMO opens significantly new possibilities when cheap or hybrid molecular mechanics/quantum mechanics methods are used to describe the solute.
Estimating the epidemic threshold on networks by deterministic connections
Authors: Li Kezan , Fu Xinchu , Small Michael , Zhu Guanghu
Published: November 2014

For many epidemic networks some connections between nodes are treated as deterministic, while the remainder are random and have different connection probabilities. By applying spectral analysis to several constructed models, we find that one can estimate the epidemic thresholds of these networks by investigating information from only the deterministic connections. Nonetheless, in these models, generic nonuniform stochastic connections and heterogeneous community structure are also considered. The estimation of epidemic thresholds is achieved via inequalities with upper and lower bounds, which are found to be in very good agreement with numerical simulations. Since these deterministic connections are easier to detect than those stochastic connections, this work provides a feasible and effective method to estimate the epidemic thresholds in real epidemic networks.
Circular single domains in hemispherical Permalloy nanoclusters
Authors: de Araujo Clodoaldo I. L. , Fonseca Jakson M. , Sinnecker João P. , Delatorre Rafael G. , Garcia Nicolas , Pasa André A.
Published: November 2014

We have studied ferromagnetic Permalloy clusters obtained by electrodeposition on n-type silicon. Magnetization measurements reveal hysteresis loops almost independent on temperature and very similar in shape to those obtained in nanodisks with diameter bigger than 150 nm. The spin configuration for the ground state, obtained by micromagnetic simulation, shows topological vortices with random chirality and polarization. This behavior in the small diameter clusters (∼80 nm) is attributed to the Dzyaloshinskii-Moriya interaction that arises in its hemispherical geometries. This magnetization behavior can be utilized to explain the magnetoresistance measured with magnetic field in plane and out of sample plane.
Vlasov simulations of kinetic Alfvén waves at proton kinetic scales
Authors: Vásconez C. L. , Valentini F. , Camporeale E. , Veltri P.
Published: November 2014

Kinetic Alfvén waves represent an important subject in space plasma physics, since they are thought to play a crucial role in the development of the turbulent energy cascade in the solar wind plasma at short wavelengths (of the order of the proton gyro radius ρp and/or inertial length dp and beyond). A full understanding of the physical mechanisms which govern the kinetic plasma dynamics at these scales can provide important clues on the problem of the turbulent dissipation and heating in collisionless systems. In this paper, hybrid Vlasov-Maxwell simulations are employed to analyze in detail the features of the kinetic Alfvén waves at proton kinetic scales, in typical conditions of the solar wind environment (proton plasma beta βp = 1). In particular, linear and nonlinear regimes of propagation of these fluctuations have been investigated in a single-wave situation, focusing on the physical processes of collisionless Landau damping and wave-particle resonant interaction. Interestingly, since for wavelengths close to dp and βp ≃ 1 (for which ρp ≃ dp) the kinetic Alfvén waves have small phase speed compared to the proton thermal velocity, wave-particle interaction processes produce significant deformations in the core of the particle velocity distribution, appearing as phase space vortices and resulting in flat-top velocity profiles. Moreover, as the Eulerian hybrid Vlasov-Maxwell algorithm allows for a clean almost noise-free description of the velocity space, three-dimensional plots of the proton velocity distribution help to emphasize how the plasma departs from the Maxwellian configuration of thermodynamic equilibrium due to nonlinear kinetic effects.
Ab initio study of point defects in PbSe and PbTe: Bulk and nanowire
Authors: Wrasse E. O. , Venezuela P. , Baierle R. J.
Published: November 2014

First principles investigations, within the spin-polarized density functional theory, are performed to study energetic stability and electronic properties of point defects (vacancies and antisites) in PbSe and PbTe: bulk and nanowire (NW). Our results show that the energetic stability of these defects is ruled by relaxation process. These defects have lower formation energies in the nanowire structures as compared to the bulk, being more stable in the surface of the NWs. We also show that in the bulk system only one charge state is stable, otherwise, due to the larger band gaps, more than one charge state may be stable in the NWs. In addition, we have investigated how the presence of intrinsic defects affects the electronic properties of bulk and NW systems. Vacancies give rise to new electronic states near to the edges of the valence and conduction bands while the energetic position of the electronic states from antisites depends on the charge state, being localized inside the band gap or near the edges of the valence or conduction bands. We discuss how these changes in the electronic properties due to intrinsic defects may affect the thermoelectric properties of PbSe and PbTe NWs.
Second-harmonic generation studies of implantation defects depth profile in hydrogen implanted garnet film
Authors: Bonda A. , Uba S. , Uba L.
Published: November 2014

We demonstrate that complete depth profile of structural defects induced by ion implantation, with spatially separated lattice strain and implant ion contributions can be obtained with the use of second-harmonic generation (SHG) effect. The SHG effect was measured in transmission geometry for (111)-oriented garnet films implanted with H2+ ions of 60 keV energy and 1.5 × 1016 cm−2 dose, and etched to different depths along implantation range. Extremely strong sensitivity of the measured SHG intensity patterns in implanted samples on angle of incidence was found. The integral d¯ and differential d¯′ depth profiles of nonlinear optical susceptibility tensor were obtained from the experiment with the use of a phenomenological model developed for crystals of C3v symmetry. Direct correlation between perpendicular strain-related part of d¯′ profile and the induced effective magnetic anisotropy field is shown. Prominent peak in d¯′ located much deeper than the strain profile range was found, and its origin as related to the effect induced by hydrogen presence in the garnet crystal structure was interpreted.
Enhanced ferroelectric properties in Bi0.86Sm0.14FeO3–based ceramics
Authors: Shi Xin Xin , Qin Ying , Chen Xiang Ming
Published: November 2014

1 at. % Ti-doping on the B-site combined with a modified rapid liquid-phase sintering technique was conducted to improve the ferroelectric properties in Bi0.86Sm0.14FeO3 multiferroic ceramics. A tenfold increase of the remnant polarization was achieved in the present ceramics compared with the samples without Ti-doing and prepared by conventional solid state sintering, but the dielectric results and conductivities refuted the generally considered mechanism of suppression of leakage current or dielectric loss. Further investigation preferred an explanation of softening effects, which could be induced by donor doping and random orientation of defect dipoles during quenching process of the rapid liquid-phase sintering, and the ferroelectric data of the second heat-treated and polarized samples well supported such explanation.
Giant enhancement of terahertz emission from nanoporous GaP
Authors: Atrashchenko A. , Arlauskas A. , Adomavičius R. , Korotchenkov A. , Ulin V. P. , Belov P. , Krotkus A. , Evtikhiev V. P.
Published: November 2014

In this paper, we have studied the emission of terahertz radiation from nanoporous semiconductor matrices of GaP excited by the femtosecond laser pulses. We observe 3–4 orders of magnitude increase of terahertz radiation emission from the nanoporous matrix compared to bulk material. The effect is mainly related to drastic increase of the sample surface and pinning of conducting electrons to surface states. This result opens up a promising way to create powerful sources of terahertz radiation using nanoporous semiconductors.
Tellurium doping effect in avalanche-mode amorphous selenium photoconductive film
Authors: Park Wug-Dong , Tanioka Kenkichi
Published: November 2014

Amorphous selenium (a-Se) high-gain avalanche rushing amorphous photoconductor (HARP) film has been used for highly sensitive imaging devices. To improve the spectral response of a-Se HARP photoconductive film at a long wavelength, the tellurium (Te) doping effect in an 8-μm-thick a-Se HARP film was investigated. The thickness of the Te-doped a-Se layer in the 8-μm-thick a-Se HARP films was varied from 60 to 120 nm. The signal current increases significantly due to the avalanche multiplication when the target voltage is increased over the threshold voltage. In the 8-μm-thick a-Se HARP film with a Te-doped layer, the spectral response at a long wavelength was improved in comparison with the a-Se HARP film without a Te-doped layer. In addition, the increase of the lag in the 8-μm-thick a-Se HARP target with a Te-doped layer of 120 nm is caused by the photoconductive lag due to the electrons trapped in the Te-doped layer. Based on the current-voltage characteristics, spectral response, and lag characteristics of the 8-μm-thick a-Se HARP targets, the Te-doped layer thickness of 90 nm is suitable for the 8-μm-thick a-Se HARP film.
Laser ion source with solenoid field
Authors: Kanesue Takeshi , Fuwa Yasuhiro , Kondo Kotaro , Okamura Masahiro
Published: November 2014

Pulse length extension of highly charged ion beam generated from a laser ion source is experimentally demonstrated. The laser ion source (LIS) has been recognized as one of the most powerful heavy ion source. However, it was difficult to provide long pulse beams. By applying a solenoid field (90 mT, 1 m) at plasma drifting section, a pulse length of carbon ion beam reached 3.2 μs which was 4.4 times longer than the width from a conventional LIS. The particle number of carbon ions accelerated by a radio frequency quadrupole linear accelerator was 1.2 × 1011, which was provided by a single 1 J Nd-YAG laser shot. A laser ion source with solenoid field could be used in a next generation heavy ion accelerator.
Axonal amyloid precursor protein and its fragments undergo somatodendritic endocytosis and processing
Authors: Niederst Emily D. , Reyna Sol M. , Goldstein Lawrence S. B.
Published: November 2014

Deposition of potentially neurotoxic Aβ fragments derived from amyloid precursor protein (APP) at synapses may be a key contributor to Alzheimer's disease. However, the location(s) of proteolytic processing and subsequent secretion of APP fragments from highly compartmentalized, euploid neurons that express APP and processing enzymes at normal levels is not well understood. To probe the behavior of endogenous APP, particularly in human neurons, we developed a system using neurons differentiated from human embryonic stem cells, cultured in microfluidic devices, to enable direct biochemical measurements from axons. Using human or mouse neurons in these devices, we measured levels of Aβ, sAPPα, and sAPPβ secreted solely from axons. We found that a majority of the fragments secreted from axons were processed in the soma, and many were dependent on somatic endocytosis for axonal secretion. We also observed that APP and the β-site APP cleaving enzyme were, for the most part, not dependent on endocytosis for axonal entry. These data establish that axonal entry and secretion of APP and its proteolytic processing products traverse different pathways in the somatodendritic compartment before axonal entry.
Surgical Technique for Decompression of Severe Thoracic Myelopathy due to Tuberous Ossification of Ligamentum Flavum
Authors: Wang Ting , Yin Chuqiang , Wang Dechun , Li Shuzhong , Chen Xiaoliang
Published: November 2014

Study Design:

Retrospective review.

Objective:

To describe a safe surgical procedure, en bloc resection of the posterior wall of the thoracic canal, for the decompression of severe thoracic myelopathy caused by tuberous ossification of the ligamentum flavum (OLF).

Summary of Background Data:

OLF has been widely recognized as a cause of thoracic myelopathy in East Asia. Surgical decompression of thoracic myelopathy caused by OLF is technically demanding. Although several surgical decompression procedures have been described, acute neurological deterioration is common.

Materials and Methods:

Eighteen patients with severe thoracic myelopathy caused by tuberous OLF underwent posterior decompression via segmental en bloc resection of the posterior wall of the thoracic canal. The ossified ligamentum flavum, laminae, and partial facet joints of each segment were resected en bloc. Ossified dura mater was removed if present. Posterior fixation with pedicle screws was followed by lateral bone graft fusion.

Results:

The mean preoperative modified Japanese Orthopaedic Association score (total score, 11) was 4.1 (range, 2–5). Postoperatively, no neurological deterioration occurred, and all patients improved clinically. With an average follow-up of 31.2 months (range, 24–42 mo), the average modified Japanese Orthopaedic Association score was 7.8 (range, 6–10), representing a 2- to 5-point improvement. The average improvement rate was 55.2% (range, 33.3%–83.3%). Most patients were functionally independent at the last follow-up. Forty ossified segments were resected. The average time required for the resection of 1 segment was 77 minutes. Intraoperatively, dural ossification was noted in 11 patients. Complete resection was performed in all patients. Cerebrospinal fluid leakage occurred in 5 patients.

Conclusion:

Segmental en bloc resection of the posterior wall of the thoracic canal is a safe and effective alternative for OLF-related severe thoracic myelopathy.
A New Navigational Tool for Pedicle Screw Placement in Patients With Severe Scoliosis
Authors: Putzier Michael , Strube Patrick , Cecchinato Riccardo , Lamartina Claudio , Hoff Eike K.
Published: November 2014

Study Design:

Pilot study.

Objective:

To develop and validate the feasibility and accuracy of a newly designed navigational spinal instrument guiding tool for patient-matched thoracic and lumbar pedicle screw placement in patients with severe scoliosis, and to identify intraoperative challenges that may be relevant.

Summary of Background Data:

Pedicle screw placement is challenging in severely rotated scoliotic spine with small diameters and asymmetrical shape of the pedicles and vertebrae. Patient-specific drill/positioning guides with preplanned trajectory have been developed as a promising solution in spinal surgery for precise screw insertion.

Methods:

In 4 patients with severe scoliosis, navigational templates and models of all vertebrae to be instrumented were manufactured using a computed tomography (CT)-based 3-dimensional model of the thoracic and lumbar spine. The guides were designed differently for thoracic and lumbar segments according to the individual anatomy to achieve an optimal coupling to the surface of the patient’s spine, to maximize the stability of the device itself, and to increase user friendliness for the complete screw positioning process. Intraoperative challenges and opportunities for device and process improvements regarding the handling of the guides during the surgery were recorded. Postoperatively, the intrapedicular screw positions were evaluated versus the preoperative plan and evaluated for cortical violation based on CT scans.

Results:

A total of 76 pedicle screws were implanted (56 thoracic, 20 lumbar). Two screws (2.6%) were assessed to be misplaced intraoperatively and repositioned. Eighty-four percent of the pedicle screws were completely intrapedicular, 96.1% within <2 mm cortical breech. CT scans did not demonstrate medial pedicle violation, or misplaced screw contact to neurovascular structures. No screw-related clinical complaints were reported postoperatively.

Conclusions:

The new custom-made positioning guide is a feasible navigational tool that permits a safe and accurate implantation of pedicle screws in patients with severe scoliosis.
Efficacy of Poly(d,l-Lactic Acid-co-Glycolic acid)-Poly(Ethylene Glycol)-Poly(d,l-Lactic Acid-co-Glycolic Acid) Thermogel As a Barrier to Prevent Spinal Epidural Fibrosis in a Postlaminectomy Rat Model
Authors: Li Xiangqian , Chen Lin , Lin Hong , Cao Luping , Cheng Ji’an , Dong Jian , Yu Lin , Ding Jiandong
Published: November 2014

Study Design:

Experimental animal study.

Objective:

The authors conducted a study to determine the efficacy and safety of the poly(d,l-lactic acid-co-glycolic acid)-poly(ethylene glycol)-poly(d,l-lactic acid-co-glycolic acid) (PLGA-PEG-PLGA) thermogel to prevent peridural fibrosis in an adult rat laminectomy model.

Summary of Background Data:

Peridural fibrosis often occurs after spinal laminectomy. It might cause persistent back and/or leg pain postoperatively and make a reoperation more difficult and dangerous. Various materials have been used to prevent epidural fibrosis, but only limited success has been achieved.

Materials and Methods:

The PLGA-PEG-PLGA thermogel was synthesized by us. Total L3 laminectomies were performed on 24 rats. The PLGA-PEG-PLGA thermogel or chitosan (CHS) gel (a positive control group) was applied to the operative sites in a blinded manner. In the control group, the L3 laminectomy was performed and the defect was irrigated with the NS solution 3 times. All the rats were killed 4 weeks after the surgery.

Results:

The cytotoxicity of this thermogel was evaluated in vitro and the result demonstrated that no evidence of cytotoxicity was observed. The extent of epidural fibrosis, the area of epidural fibrosis, and the density of the fibroblasts and blood vessel were evaluated histologically. There were statistical differences among the PLGA-PEG-PLGA thermogel or CHS gel group compared with the control group. Although there was no difference between the PLGA-PEG-PLGA thermogel and CHS gel, the efficiency of the PLGA-PEG-PLGA thermogel was shown to be slightly improved compared with the CHS gel.

Conclusions:

The biocompatibility of the PLGA-PEG-PLGA thermogel was proven well. The application of this thermogel effectively reduced epidural scarring and prevented the subsequent adhesion to the dura mater. No side effects were noted in the rats.
The Use of a Polyetheretherketone (PEEK) Implant to Reconstruct the Midface Region
Authors: Hussain Rumana N. , Clark Martin , Berry-Brincat Antonella
Published: November 2014

A good functional and cosmetic result after midfacial reconstructive surgical procedures is of paramount importance. We describe the use of a Polyetheretherketone (PEEK) implant to reconstruct the midface area, after extensive mutilating surgery due to an infiltrative skin tumor. A 67-year-old male patient underwent multiple and extensive surgeries to the left cheek and lower lid because of a highly aggressive metatypical basal cell carcinoma. Complete resection of the recurrent tumor resulted in a cosmetically evident absent cheek contour and facial deformity. The PEEK implant was used to restore the bony cheek contour, with good aesthetic outcome and restoration of the facial symmetry. Preoperative planning with 3-dimensional CT scans allow for customization of the implant. PEEK implants have been scantily described in the periorbital region. The material has a very low reported morbidity and also has the advantage of improving intraoperative predictability and reducing surgical time in complex reconstructive procedures.
Wnt signalling induces accumulation of phosphorylated β-catenin in two distinct cytosolic complexes
Authors: Gerlach Jan P. , Emmink Benjamin L. , Nojima Hisashi , Kranenburg Onno , Maurice Madelon M.
Published: November 2014

Wnt/β-catenin signalling controls development and adult tissue homeostasis and causes cancer when inappropriately activated. In unstimulated cells, an Axin1-centred multi-protein complex phosphorylates the transcriptional co-activator β-catenin, marking it for degradation. Wnt signalling antagonizes β-catenin proteolysis, leading to its accumulation and target gene expression. How Wnt stimulation alters the size distribution, composition and activity of endogenous Axin1 complexes remains poorly understood. Here, we employed two-dimensional blue native/SDS-PAGE to analyse endogenous Axin1 and β-catenin complexes during Wnt signalling. We show that the size range of Axin1 complexes is conserved between species and remains largely unaffected by Wnt stimulation. We detect a striking Wnt-dependent, cytosolic accumulation of both non-phosphorylated and phosphorylated β-catenin within a 450 kDa Axin1-based complex and in a distinct, Axin1-free complex of 200 kDa. These results argue that during Wnt stimulation, phosphorylated β-catenin is released from the Axin1 complex but fails to undergo immediate degradation. Importantly, in APC-mutant cancer cells, the distribution of Axin1 and β-catenin complexes strongly resembles that of Wnt-stimulated cells. Our findings argue that Wnt signals and APC mutations interfere with the turnover of phosphorylated β-catenin. Furthermore, our results suggest that the accumulation of small-sized β-catenin complexes may serve as an indicator of Wnt pathway activity in primary cancer cells.
Dynamics of osmosis in a porous medium
Authors: Cardoso Silvana S. S. , Cartwright Julyan H. E.
Published: November 2014

We derive from kinetic theory, fluid mechanics and thermodynamics the minimal continuum-level equations governing the flow of a binary, non-electrolytic mixture in an isotropic porous medium with osmotic effects. For dilute mixtures, these equations are linear and in this limit provide a theoretical basis for the widely used semi-empirical relations of Kedem & Katchalsky (Kedem & Katchalsky 1958
Biochim. Biophys. Acta
27
, 229–246 (
doi:10.1016/0006-3002(58)90330-5
), which have hitherto been validated experimentally but not theoretically. The above linearity between the fluxes and the driving forces breaks down for concentrated or non-ideal mixtures, for which our equations go beyond the Kedem–Katchalsky formulation. We show that the heretofore empirical solute permeability coefficient reflects the momentum transfer between the solute molecules that are rejected at a pore entrance and the solvent molecules entering the pore space; it can be related to the inefficiency of a Maxwellian demi-demon.
Interactive analysis and quality assessment of single-cell copy-number variations
Authors: Garvin Tyler , Aboukhalil Robert , Kendall Jude , Baslan Timour , Atwal Gurinder S. , Hicks James , Wigler Michael , Schatz Michael C.
Published: November 2014

We present an open-source visual-analytics web platform, Ginkgo (http://qb.cshl.edu/ginkgo), for the interactive analysis and quality assessment of single-cell copy-number alterations. Ginkgo automatically constructs copy-number profiles of individual cells from mapped reads, as well as constructing phylogenetic trees of related cells. We validate Ginkgo by reproducing the results of five major studies and examine the data characteristics of three commonly used single-cell amplification techniques to conclude DOP-PCR to be the most consistent for CNV analysis.
Optimization of the crystallizability of a single-chain antibody fragment
Authors: Škerlová Jana , Král Vlastimil , Fábry Milan , Sedláček Juraj , Veverka Václav , Řezáčová Pavlína
Published: November 2014

Single-chain variable antibody fragments (scFvs) are molecules with immense therapeutic and diagnostic potential. Knowledge of their three-dimensional structure is important for understanding their antigen-binding mode as well as for protein-engineering approaches such as antibody humanization. A major obstacle to the crystallization of single-chain variable antibody fragments is their relatively poor homogeneity caused by spontaneous oligomerization. A new approach to optimization of the crystallizability of single-chain variable antibody fragments is demonstrated using a representative single-chain variable fragment derived from the anti-CD3 antibody MEM-57. A Thermofluor-based assay was utilized to screen for optimal conditions for antibody-fragment stability and homogeneity. Such an optimization of the protein storage buffer led to a significantly improved ability of the scFv MEM-57 to yield crystals.
Expression, crystallization and preliminary crystallographic study of the functional mutant (N60K) of nonstructural protein 9 fromHuman coronavirus HKU1
Authors: Chen Xia , Tan Yusheng , Wang Fenghua , Wang Jinshan , Zhao Qi , Li Shuang , Fu Sheng , Chen Cheng , Yang Haitao
Published: November 2014

Human coronavirus HKU1(HCoV-HKU1), which mainly causes acute self-limited respiratory-tract infections, belongs to group A of theBetacoronavirusgenus. Coronavirus genomes encode 16 nonstructural proteins (nsp1–16), which assemble into a large replication–transcription complex mediating virus propagation. Nonstructural protein 9, which binds to the single-stranded DNA/RNA, has been shown to be indispensible for viral replication. Interestingly, a functional mutant (N60K) of nsp9 was identified to compensate for a 6 nt insertion mutation of the 3′-untranslated region (UTR), which is critical for viral RNA synthesis. It has been proposed that the N60K mutation may cause certain conformational changes of nsp9 to rescue the defective insertion mutant. To further investigate the underlying structural mechanism, the N60K mutant of nsp9 from HCoV-HKU1 was successfully crystallized in this study. The crystals diffracted to 2.6 Å resolution and belonged to space groupP212121, with unit-cell parametersa= 31.9,b= 85.0,c= 95.0 Å. Two molecules were identified per asymmetric unit.
Crystallization and preliminary X-ray diffraction analysis of the Sel1-like repeats of SEL1L
Authors: Jeong Hanbin , Lee Hakbong , Lee Changwook
Published: November 2014

Terminally misfolded or unassembled proteins are selectively recognized and cleared by the ER-associated degradation (ERAD) pathway. Suppressor/enhancer of lin-12-like (SEL1L), a component of the dislocation machinery containing the E3 ubiquitin ligase Hrd1, plays an important role in selecting and transporting ERAD substrates for degradation in the endoplasmic reticulum. In this study, the purification, crystallization and preliminary X-ray diffraction analysis of recombinant mouse SEL1L (residues 348–533) are reported. The crystals were obtained by the hanging-drop vapour-diffusion method at pH 8.5 and 277 K using 30% 2-propanol as a precipitant. Optimized crystals diffracted to 3.3 Å resolution at a synchrotron-radiation source. Preliminary X-ray diffraction analysis revealed that the crystals belonged to space groupP21and contained four molecules per asymmetric unit, with a solvent content of 44%.
Expression, purification and crystallization of a novel carbohydrate-binding module from theRuminococcus flavefacienscellulosome
Authors: Venditto Immacolata , Centeno Maria S. J. , Ferreira Luis M. A. , Fontes Carlos M. G. A. , Najmudin Shabir
Published: November 2014

Anaerobic bacteria organize carbohydrate-active enzymes into a multi-component complex, the cellulosome, which degrades cellulose and hemicellulose highly efficiently. Genome sequencing ofRuminococcus flavefaciensFD-1 offers extensive information on the range and diversity of the enzymatic and structural components of the cellulosome. TheR. flavefaciensFD-1 genome encodes over 200 dockerin-containing proteins, most of which are of unknown function. One of these modular proteins comprises a glycoside hydrolase family 5 catalytic module (GH5) linked to an unclassified carbohydrate-binding module (CBM-Rf1) and a dockerin. The novel CBM-Rf1 has been purified and crystallized. The crystals belonged to the trigonal space groupR32:H. The CBM-Rf1 structure was determined by a multiple-wavelength anomalous dispersion experiment usingAutoSolfrom thePHENIXsuite using both selenomethionyl-derivative and native data to resolutions of 2.28 and 2.0 Å, respectively.
Crystallization and preliminary X-ray crystallographic analysis of a putative acetylxylan esterase fromTalaromyces cellulolyticus
Authors: Watanabe Masahiro , Ishikawa Kazuhiko
Published: November 2014

Acetylxylan esterase (AXE) catalyzes the hydrolytic cleavage of the ester bond between acetic acid and hemicellulose in plant cell walls. A putative AXE gene exhibiting high homology to carbohydrate esterase family 3 was found in the genome database of the fungusTalaromyces cellulolyticus(formerly known asAcremonium cellulolyticus). A truncated form of the protein, the catalytic domain of the enzyme, was prepared and crystallized. The best crystal was obtained at 293 K using 0.17 Mammonium sulfate, 28% PEG 4000, 5%(v/v) glycerol, 0.5%(w/v)n-octyl-β-D-glucoside. X-ray diffraction data were collected to 1.50 Å resolution. The crystal belonged to space groupP41212 orP43212, with unit-cell parametersa= 70.90,b= 70.90,c= 87.09 Å. One enzyme molecule per asymmetric unit gave a crystal volume per protein mass (VM) of 2.62 Å3 Da−1and a solvent content of 53.0%(v/v).
The effect of sulfur dioxide on iron, copper and brass
Authors: Kilinççeker Güray , Taze Nurşen , Galip Hasan , Yazici Birgül
Published: November 2014

Purpose

The purpose of this paper is to study, under laboratory conditions, the corrosive effect of sulfur dioxide (SO2) present in the atmosphere of urban and industrial areas on various construction materials.

Design/methodology/approach

Iron, copper and brass metals were exposed to SO2 gas at different relative humidities that were obtained using analytical grade glycerol and water mixtures. The corrosion rates (mdd) of the samples were determined over 120 h using the weight‐loss method under fixed relative humidity (rH) conditions. The change of galvanic current was measured as a function of exposure time over 196 h. Nyquist diagrams were obtained in 10−3 M Na2SO4 solutions with a pH value of 7.2, which was assumed to correspond to 100 percent rH conditions.

Findings

The obtained data showed that the corrosion rate of the studied metals increased with increasing rH. The corrosion rate of the metals decreased with exposure time, due to accumulation of corrosion products over the surface of the metals. However, the surface films of corrosion products on the metal surfaces were not stable and the corrosion rate increased again with time when the surface film disappeared.

Research limitations/implications

The atmospheric corrosion of the industrial materials is dependent upon the rH and SO2 concentration. The corrosive effect of SO2 present in the atmosphere of urban and industrial areas on various construction materials can be tested under laboratory conditions.

Originality/value

The effects of SO2 and NH3 on the atmospheric corrosion of galvanized iron and the effect of rH on the atmospheric corrosion of defective organic coating materials were reported in literature. In this study, the corrosive effect of SO2 present in the atmosphere of urban and industrial areas on various construction materials (iron, copper and brass) under laboratory conditions was studied.
No longer the lonely species: a post‐mead perspective on animals and sociology
Authors: Myers Olin E.
Published: November 2014

Society’s relations to animals pose possible blind spots in sociological theory that may be revealed and illuminated by studying systems of human‐animal interaction. By investigating whether and how animals enter into key processes that shape self and society we may determine the ways in which animals might be included in the core subject matter of sociology. An earlier discussion of the role of animals in sociology initiated by Weber is reviewed. Issues that debate raised about the extent of linguistically‐mediated human‐animal intersubjectivity are updated. It is in principle difficult to rule out animal languages, and some animals have acquired human language. But sociology may follow a more fecund empirical route by examining successful human‐animal performances produced by enduring interspecies relationships. Following this route, this paper specifically argues that the human self should be seen to take root in the available mixed species community. To show this, the work of G.H. Mead is revisited and corrected in light of recent work on early human development, and conceptual analyses of language, the body, and the self. The formation of the self is not dependent on only linguistic exchanges; a nonverbal nonhuman other can contribute to the self‐reflective sense of being a human self. Based on this reasoning, examples of studies of humans with wild and domestic animals illustrate the potential for a human‐animal sociology.