bluuebunny/crossref_metadata_2025 huggingface dataset:
A taxonomy for solar fuels generators
Authors: Nielander Adam C. , Shaner Matthew R. , Papadantonakis Kimberly M. , Francis Sonja A. , Lewis Nathan S.
Published: September 2014

The three basic types of solar fuels generators: photoelectrochemical cells, photovoltaic cells, and photoelectrosynthetic particulate/molecular photocatalysts.
Total saponins fromRosa laevigataMichx fruit attenuates hepatic steatosis induced by high-fat diet in rats
Authors: Dong Deshi , Qi Yan , Xu Lina , Yin Lianhong , Xu Youwei , Han Xu , Zhao Yanyan , Peng Jinyong
Published: September 2014

The protective effects of total saponins fromRosa laevigataMichx fruit (RLTS) in high-fat diet (HFD)-induced rats were investigated.
Silanization of solid surfaces via mercaptopropylsilatrane: a new approach of constructing gold colloid monolayers
Authors: Chen Wen-Hao , Tseng Yen-Ta , Hsieh Shuchen , Liu Wan-Chun , Hsieh Chiung-Wen , Wu Chin-Wei , Huang Chen-Han , Lin Hsing-Ying , Chen Chao-Wen , Lin Pei-Ying , Chau Lai-Kwan
Published: September 2014

Mercaptopropylsilatrane (MPS) was investigated as a novel self-assembled film on silica surfaces and also as a novel adhesive layer for the construction of a gold colloid monolayer on silica surfaces.
Molecular dynamics study of Congo red interaction with carbon nanotubes
Authors: Panczyk Tomasz , Wolski Pawel , Jagusiak Anna , Drach Mateusz
Published: September 2014

Molecular dynamics simulations prove that Congo red adsorption on carbon nanotubes is very strong and by varying pH filling/unfilling of inner cavities of the nanotubes can be accomplished.
Facile fabrication and optoelectronic properties of platinum octaethylporphyrin microsheets
Authors: Zhang Qing-Guo , Lu Ying , Wang Feng-Xia , Wei Ying , Liu Yong-Qiang , Yang Bo , Pan Ge-Bo
Published: September 2014

PtOEP microsheets with well-defined shape and smooth surface were fabricated, which showed active optical waveguides, photodetector and photoswitching properties.
Synthesis and characterization of novel polyimides from 4,4′-bis(5-amino-2-pyridinoxy)diphenyl ether, 4,4′-bis(5-amino-2-pyridinoxy)diphenyl thioether and 4,4′-bis(5-amino-2-pyridinoxy)diphenyl sulfone
Authors: Guan Yue , Wang Daming , Wang Zhen , Dang Guodong , Chen Chunhai , Zhou Hongwei , Zhao Xiaogang
Published: September 2014

The performance data of the polyimides was comprehensively tested and we find the reverse influence of –O– and –S– groups in diamine and dianhydride on Tg of the polyimides.
Electro-catalytically active Au@Pt nanoparticles for hydrogen evolution reaction: an insight into a tryptophan mediated supramolecular interface towards a universal core–shell synthesis approach
Authors: Srivastava Sarvesh Kumar , del Río Jonathan Sabaté , O'Sullivan Ciara K. , Ogino Chiaki , Kondo Akihiko
Published: September 2014

We report an eco-friendly, one-pot, room-temperature method for the rapid synthesis of electrocatalytically active Au@Pt (50 nm) bimetallic nanoparticles via tryptophan (Trp) induced interface in an aqueous environment.
CO2 splitting into CO and O2 in micro-tubular solid oxide electrolysers
Authors: Kleiminger L. , Li T. , Li K. , Kelsall G. H.
Published: September 2014

Efficient high temperature CO2 to CO and O2 conversion achieved using micro-tubular solid oxide electrolysers prepared by dual-layer co-extrusion.
Comparison of nonlinear optical chromophores containing different conjugated electron-bridges: the relationship between molecular structure-properties and macroscopic electro-optic activities of materials
Authors: Wu Jieyun , Xiao Hongyan , Qiu Ling , Zhen Zhen , Liu Xinhou , Bo Shuhui
Published: September 2014

In electro-optic (EO) materials, realization of large EO coefficients for organic EO materials requires the simultaneous optimization of chromophore first hyperpolarizability, acentric order, molecular shape etc.
Polymer translocation: the first two decades and the recent diversification
Authors: Palyulin Vladimir V. , Ala-Nissila Tapio , Metzler Ralf
Published: September 2014

This review article provides a state-of-the-art summary of polymer translocation with an emphasis on scaling and recent conceptual advances.
Poly(acrylic acid) gel as a polysulphide blocking layer for high-performance lithium/sulphur battery
Authors: Zhang Sheng S. , Tran Dat T. , Zhang Zhengcheng
Published: September 2014

A poly(acrylic acid)-coated sulphur cathode significantly improves the cyclability of a Li/S battery because the resulting gel blocks the out-diffusion of lithium polysulphide via hydrogen bonds.
Distinct roles for histone chaperones in the deposition of Htz1 in chromatin
Authors: Liu Hongde , Zhu Min , Mu Yawen , Liu Lingjie , Li Guanghui , Wan Yakun
Published: September 2014

Histone variant Htz1 substitution for H2A plays important roles in diverse DNA transactions. Histone chaperones Chz1 and Nap1 (nucleosome assembly protein 1) are important for the deposition Htz1 into nucleosomes. In literatures, it was suggested that Chz1 is a Htz1–H2B-specific chaperone, and it is relatively unstructured in solution but it becomes structured in complex with the Htz1–H2B histone dimer. Nap1 (nucleosome assembly protein 1) can bind (H3–H4)2 tetramers, H2A–H2B dimers and Htz1–H2B dimers. Nap1 can bind H2A–H2B dimer in the cytoplasm and shuttles the dimer into the nucleus. Moreover, Nap1 functions in nucleosome assembly by competitively interacting with non-nucleosomal histone–DNA. However, the exact roles of these chaperones in assembling Htz1-containing nucleosome remain largely unknown. In this paper, we revealed that Chz1 does not show a physical interaction with chromatin. In contrast, Nap1 binds exactly at the genomic DNA that contains Htz1. Nap1 and Htz1 show a preferential interaction with AG-rich DNA sequences. Deletion of chz1 results in a significantly decreased binding of Htz1 in chromatin, whereas deletion of nap1 dramatically increases the association of Htz1 with chromatin. Furthermore, genome-wide nucleosome-mapping analysis revealed that nucleosome occupancy for Htz1p-bound genes decreases upon deleting htz1 or chz1, suggesting that Htz1 is required for nucleosome structure at the specific genome loci. All together, these results define the distinct roles for histone chaperones Chz1 and Nap1 to regulate Htz1 incorporation into chromatin.
Outage performance of multiple‐input–multiple‐output decode‐and‐forward relay networks with the Nth‐best relay selection scheme in the presence of co‐channel interference
Authors: Li Guoxin , Chen Jin , Huang Yuzhen , Ren Guochun
Published: September 2014

In this study, a dual‐hop multiple‐input–multiple‐output relay network with the Nth‐best relay selection scheme in the presence of co‐channel interference is studied. Specifically, the Nth‐best relay is selected based on the channel state information (CSI) of the first hop. The authors first consider the CSI is perfect feedback and derive exact as well as asymptotic closed‐form expressions for the outage probability. Results reveal that the diversity order of NR × min{NS(K − N + 1), ND} is achieved when there is no feedback delay, where NS, NR and ND represent the number of antennas at the source, the relays and the destination, respectively, K is the number of the relays and N (1 ≤ N ≤ K) represents the rank of relay chosen. Then, they investigate the outage performance of the system with feedback delay, and exact and asymptotic outage probability expressions are also obtained. Results illustrate that outdated CSI degrades the diversity order of the system to min{NR, ND}, which is independent of the number of antennas at the source, the number of relays and the rank of the relay chosen. The findings of the study provide valuable insights into the practical system design.
Digital design of adaptive repetitive control of linear systems with time‐varying periodic disturbances
Authors: Kurniawan Edi , Cao Zhenwei , Man Zhihong
Published: September 2014

The repetitive control is well known for rejecting the periodic disturbances. However, most of the existing repetitive control algorithms assume that either the plant is known or the disturbance period is fixed. This study proposes the digital design of adaptive repetitive control for a class of linear systems subject to time‐varying periodic disturbances, whose periods are assumed to be identifiable. The proposed control is based on the direct adaptive control scheme and the internal model principle. A comparative study is conducted and the effectiveness of the approach is verified in simulations and experiments on a servo motor system.
Second‐order consensus of multi‐agent systems with noise
Authors: Sun Wen , Lü Jinhu , Yu Xinghuo , Chen Shihua
Published: September 2014

This study studies second‐order consensus of multi‐agent systems with noise in a leaderless architecture. Two distributed consensus algorithms are designed and sufficient conditions are established, which character how much the noise intensity or the delay multi‐agent systems can stand such that second‐order consensus can be reached almost surely for a given coupling strength and topology structure. Simulations are given to illustrate the effectiveness of the proposed consensus algorithms.
Reaching law‐based sliding mode congestion control for communication networks
Authors: Bartoszewicz Andrzej , Leśniewski Piotr
Published: September 2014

In this study, a new reaching law for sliding mode control of discrete time systems is proposed and applied to solve the problem of congestion avoidance in multi‐source, connection oriented data transmission networks. Since the proposed reaching law does not require switching of the sliding variable between positive and negative values in each successive control step, it leads to chattering free operation, does not cause overshoots and helps achieve 100% exploitation of the bottleneck link available bandwidth. Furthermore, the proposed controller always generates bounded data transmission rates. The rates are limited by design parameters and they do not depend on the network initial conditions. The properties of the proposed controller are stated as three theorems, formally proved and verified in a simulation example.
Single‐image shadow detection and removal using local colour constancy computation
Authors: Yuan Xingsheng , Ebner Marc , Wang Zhengzhi
Published: September 2014

This study is concerned with the problem of shadow detection and removal from single images of natural scenes. In this work, the authors propose a shadow detection method with a surface descriptor, termed colour‐shade, which allows them to include the physical considerations derived from the image formation model capturing gradual colour surface variations. The authors incorporate a colour‐shade descriptor into the condition random field model to find same illumination pairs and to obtain coherent shadow regions. The authors propose a shadow removal method using an improved local colour constancy computation, which uses anisotropic diffusion to estimate the illuminant locally for each image pixel in shadow. The authors evaluate their method on two shadow detection databases. The experimental results demonstrate that their shadow detection and removal method is state of the art.
Long wavelength emitting GaInN quantum wells on metamorphic GaInN buffer layers with enlarged in-plane lattice parameter
Authors: Däubler J. , Passow T. , Aidam R. , Köhler K. , Kirste L. , Kunzer M. , Wagner J.
Published: September 2014

Metamorphic (i.e., linear composition graded) GaInN buffer layers with an increased in-plane lattice parameter, grown by plasma-assisted molecular beam epitaxy, were used as templates for metal organic vapor phase epitaxy (MOVPE) grown GaInN/GaInN quantum wells (QWs), emitting in the green to red spectral region. A composition pulling effect was observed allowing considerable higher growth temperatures for the QWs for a given In composition. The internal quantum efficiency (IQE) of the QWs was determined by temperature and excitation power density dependent photoluminescence (PL) spectroscopy. An increase in IQE by a factor of two was found for green emitting QWs grown on metamorphic GaInN buffer compared to reference samples grown on standard GaN buffer layers. The ratio of room temperature to low temperature intensity PL of the red emitting QWs were found to be comparable to the PL efficiency of green emitting QWs, both grown on metamorphic GaInN buffers. The excitation density and well width dependence of the IQE indicate a reduction of the quantum confined Stark effect upon growth on GaInN buffer layers with increased in-plane lattice parameter.
Metastable Lennard-Jones fluids. III. Bulk viscosity
Authors: Baidakov Vladimir G. , Protsenko Sergey P.
Published: September 2014

The method of equilibrium molecular-dynamics simulation in combination with the Green-Kubo formula has been used to calculate the bulk viscosity of a Lennard-Jones fluid. Calculations have been made at temperatures 0.4 ≤ kBT/ɛ ≤ 2.0 and densities 0.0075 ≤ ρσ3 ≤ 1.2 at 116 stable and 106 metastable states of liquid and gas. The depth of penetration into the region of metastable states was limited by spontaneous nucleation. In the region of stable states the data obtained are compared with the results of previous investigations. It has been established that the system transition across the lines of liquid–gas and liquid–crystal phase equilibrium and penetration into the metastable regions of liquid and gas are connected with increasing bulk viscosity. The behavior of bulk viscosity close to the spinodal of a superheated liquid and supersaturated vapor is discussed.
Low-field nuclear magnetic resonance for the in vivo study of water content in trees
Authors: Yoder Jacob , Malone Michael W. , Espy Michelle A. , Sevanto Sanna
Published: September 2014

Nuclear magnetic resonance (NMR) and magnetic resonance imaging have long been used to study water content in plants. Approaches have been primarily based on systems using large magnetic fields (∼1 T) to obtain NMR signals with good signal-to-noise. This is because the NMR signal scales approximately with the magnetic field strength squared. However, there are also limits to this approach in terms of realistic physiological configuration or those imposed by the size and cost of the magnet. Here we have taken a different approach – keeping the magnetic field low to produce a very light and inexpensive system, suitable for bulk water measurements on trees less than 5 cm in diameter, which could easily be duplicated to measure on many trees or from multiple parts of the same tree. Using this system we have shown sensitivity to water content in trees and their cuttings and observed a diurnal signal variation in tree water content in a greenhouse. We also demonstrate that, with calibration and modeling of the thermal polarization, the system is reliable under significant temperature variation.
Argon metastable dynamics and lifetimes in a direct current microdischarge
Authors: Stefanović Ilija , Kuschel Thomas , Schröter Sandra , Böke Marc
Published: September 2014

In this paper we study the properties of a pulsed dc microdischarge with the continuous flow of argon. Argon metastable lifetimes are measured by tunable diode laser absorption spectroscopy (TDLAS) and are compared with calculated values which yield information about excitation and de-excitation processes. By increasing the gas flow-rate about 5 times from 10 to 50 sccm, the Arm lifetime increases from 1 to 5 μs due to the reduction of metastable quenching with gas impurities. Optical emission spectroscopy reveals nitrogen and water molecules as the main gas impurities. The estimated N2 density [N2] = 0.1% is too low to explain the measured metastable lifetimes. Water impurity was found to be the main de-excitation source of argon metastable atoms due to high quenching coefficients. The water impurity level of [H2O] = 0.15% to 1% is sufficient to bring calculated metastable lifetimes in line with experiments. The maximum value of water content in the discharge compared to the argon atoms is estimated to approximately 6%, due to the large surface to volume ratio of the microdischarge. The current pulse releases the water molecules from the electrode surface and they are either re-adsorbed in the time between 0.4 ms for [H2O] = 1% and 2.6 ms for [H2O] = 0.15% or pumped out of the discharge with the speed equal to the gas flow-rate. Depending on its partial pressure, the water impurity re-adsorption time is of the order of magnitude or less then the argon gas residence time.
Bogomolov multiplier, double class-preserving automorphisms, and modular invariants for orbifolds
Authors: Davydov Alexei
Published: September 2014

We describe the group $Aut_{br}^1({\cal Z}(G))$Autbr1(Z(G)) of braided tensor autoequivalences of the Drinfeld centre of a finite group G isomorphic to the identity functor (just as a functor). We prove that the semi-direct product Out2 − cl(G)⋉B(G) of the group of double class preserving automorphisms and the Bogomolov multiplier of G is a subgroup of $Aut_{br}^1({\cal Z}(G))$Autbr1(Z(G)). An automorphism of G is double class preserving if it preserves conjugacy classes of pairs of commuting elements in G. The Bogomolov multiplier B(G) is the subgroup of its Schur multiplier H2(G, k*) of classes vanishing on abelian subgroups of G. We show that elements of $Aut^1_{br}({\cal Z}(G))$Autbr1(Z(G)) give rise to different realisations of the charge conjugation modular invariant for G-orbifolds of holomorphic conformal field theories.
Impact of higher-order flows in the moment equations on Pfirsch-Schlüter friction coefficients
Authors: Honda M.
Published: September 2014

The impact of the higher-order flows in the moment approach on an estimate of the friction coefficients is numerically examined. The higher-order flows are described by the lower-order hydrodynamic flows using the collisional plasma assumption. Their effects have not been consistently taken into account thus far in the widely used neoclassical transport codes based on the moment equations in terms of the Pfirsch-Schlüter flux. Due to numerically solving the friction-flow matrix without using the small-mass ratio expansion, it is clearly revealed that incorporating the higher-order flow effects is of importance especially for plasmas including multiple hydrogenic ions and other lighter species with similar masses.
The influence of random indium alloy fluctuations in indium gallium nitride quantum wells on the device behavior
Authors: Yang Tsung-Jui , Shivaraman Ravi , Speck James S. , Wu Yuh-Renn
Published: September 2014

In this paper, we describe the influence of the intrinsic indium fluctuation in the InGaN quantum wells on the carrier transport, efficiency droop, and emission spectrum in GaN-based light emitting diodes (LEDs). Both real and randomly generated indium fluctuations were used in 3D simulations and compared to quantum wells with a uniform indium distribution. We found that without further hypothesis the simulations of electrical and optical properties in LEDs such as carrier transport, radiative and Auger recombination, and efficiency droop are greatly improved by considering natural nanoscale indium fluctuations.
Multiferroic composites for magnetic data storage beyond the super-paramagnetic limit
Authors: Vopson M. M. , Zemaityte E. , Spreitzer M. , Namvar E.
Published: September 2014

Ultra high-density magnetic data storage requires magnetic grains of <5 nm diameters. Thermal stability of such small magnetic grain demands materials with very large magneto-crystalline anisotropy, which makes data write process almost impossible, even when Heat Assisted Magnetic Recording (HAMR) technology is deployed. Here, we propose an alternative method of strengthening the thermal stability of the magnetic grains via elasto-mechanical coupling between the magnetic data storage layer and a piezo-ferroelectric substrate. Using Stoner-Wohlfarth single domain model, we show that the correct tuning of this coupling can increase the effective magneto-crystalline anisotropy of the magnetic grains making them stable beyond the super-paramagnetic limit. However, the effective magnetic anisotropy can also be lowered or even switched off during the write process by simply altering the applied voltage to the substrate. Based on these effects, we propose two magnetic data storage protocols, one of which could potentially replace HAMR technology, with both schemes promising unprecedented increases in the data storage areal density beyond the super-paramagnetic size limit.
Enhanced architectures for room-temperature reversible logic gates in graphene
Authors: Dragoman Daniela , Dragoman Mircea
Published: September 2014

We show that reversible two- and three-input logic gates, such as the universal Toffoli gate, can be implemented with three tilted gate electrodes patterned on a monolayer graphene flake. These reversible gates are based on the unique properties of ballistic charge carriers in graphene, which induce bandgaps in transmission for properly chosen potential barriers. The enhanced architectures for reversible logic gate implementation proposed in this paper offer a remarkable design simplification compared to standard approaches based on field-effect transistor circuits, as well as potential high-frequency operation.
Delayed feedback control and phase reduction of unstable quasi-periodic orbits
Authors: Ichinose Natsuhiro , Komuro Motomasa
Published: September 2014

The delayed feedback control (DFC) is applied to stabilize unstable quasi-periodic orbits (QPOs) in discrete-time systems. The feedback input is given by the difference between the current state and a time-delayed state in the DFC. However, there is an inevitable time-delay mismatch in QPOs. To evaluate the influence of the time-delay mismatch on the DFC, we propose a phase reduction method for QPOs and construct a phase response curve (PRC) from unstable QPOs directly. Using the PRC, we estimate the rotation number of QPO stabilized by the DFC. We show that the orbit of the DFC is consistent with the unstable QPO perturbed by a small state difference resulting from the time-delay mismatch, implying that the DFC can certainly stabilize the unstable QPO.
Cost-effective and highly sensitive cholesterol microsensors with fast response based on the enzyme-induced conductivity change of polyaniline
Authors: Fang Kuan-Chung , Chu Chia-Ho , Hsu Chen-Pin , Kang Yen-Wen , Fang Jung-Ying , Hsu Chia-Hsien , Huang Yu-Fen , Chen Chih-Chen , Li Sheng-Shian , Andrew Yeh J. , Yao Da-Jeng , Wang Yu-Lin
Published: September 2014

In this study, a cost-effective and highly sensitive cholesterol microsensor, which is consisted of cholesterol oxidase (ChOx), horseradish peroxidase (HRP), and polyaniline (PANI), was developed based on the enzyme-induced conductivity change of PANI with fast response. Hydrogen peroxide is produced via the reaction between cholesterol and ChOx, which was immobilized in a dialysis membrane. The produced hydrogen peroxide can oxidize HRP, which can be reduced by oxidizing PANI, thus resulting in decreased conductivity of the polyaniline thin film. The reduced HRP can be oxidized again by hydrogen peroxide and the cycle of the oxidation/reduction continues until all hydrogen peroxide are reacted, leading to the high sensitivity of the sensor due to the signal contributed from all hydrogen peroxide molecules. Cholesterol was detected near the physiological concentrations ranging from 100 mg/dl to 400 mg/dl with the cholesterol microsensors. The results show linear relation between cholesterol concentration and the conductivity change of the PANI. The microsensor showed no response to cholesterol when the PANI was standalone without cholesterol oxidase immobilized, indicating that the enzymatic reaction is required for cholesterol detection. The simple process of the sensor fabrication allows the sensor to be cost-effective and disposable usage. This electronic cholesterol microsensor is promising for point-of-care health monitoring in cholesterol level with low cost and fast response.
Tailoring double Fano profiles with plasmon-assisted quantum interference in hybrid exciton-plasmon system
Authors: Zhao Dongxing , Wu Jiarui , Gu Ying , Gong Qihuang
Published: September 2014

We propose tailoring of the double Fano profiles via plasmon-assisted quantum interference in a hybrid exciton-plasmon system. Tailoring is performed by the interference between two exciton channels interacting with a common localized surface plasmon. Using an applied field of low intensity, the absorption spectrum of the hybrid system reveals a double Fano lineshape with four peaks. For relatively large field intensity, a broad flat window in the absorption spectrum appears which results from the destructive interference between excitons. Because of strong constructive interference, this window vanishes as intensity is further increased. We have designed a nanometer bandpass optical filter for visible light based on tailoring of the optical spectrum. This study provides a platform for quantum interference that may have potential applications in ultracompact tunable quantum devices.
Is the Perception of 3D Shape from Shading Based on Assumed Reflectance and Illumination?
Authors: Todd James T. , Egan Eric J. L. , Phillips Flip
Published: September 2014

The research described in the present article was designed to compare three types of image shading: one generated with a Lambertian BRDF and homogeneous illumination such that image intensity was determined entirely by local surface orientation irrespective of position; one that was textured with a linear intensity gradient, such that image intensity was determined entirely by local surface position irrespective of orientation; and another that was generated with a Lambertian BRDF and inhomogeneous illumination such that image intensity was influenced by both position and orientation. A gauge figure adjustment task was used to measure observers' perceptions of local surface orientation on the depicted surfaces, and the probe points included 60 pairs of regions that both had the same orientation. The results show clearly that observers' perceptions of these three types of stimuli were remarkably similar, and that probe regions with similar apparent orientations could have large differences in image intensity. This latter finding is incompatible with any process for computing shape from shading that assumes any plausible reflectance function combined with any possible homogeneous illumination.
Existence and symmetry of positive ground states for a doubly critical Schrödinger system
Authors: Chen Zhijie , Zou Wenming
Published: September 2014

We study the following doubly critical Schrödinger system:
\[
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="StartLayout Enlarged left-brace 1st Row minus normal upper Delta u minus StartFraction lamda 1 Over StartAbsoluteValue x EndAbsoluteValue squared EndFraction u equals u Superscript 2 Super Superscript asterisk Superscript minus 1 Baseline plus nu alpha u Superscript alpha minus 1 Baseline v Superscript beta Baseline comma x element-of double-struck upper R Superscript upper N Baseline comma 2nd Row minus normal upper Delta v minus StartFraction lamda 2 Over StartAbsoluteValue x EndAbsoluteValue squared EndFraction v equals v Superscript 2 Super Superscript asterisk Superscript minus 1 Baseline plus nu beta u Superscript alpha Baseline v Superscript beta minus 1 Baseline comma x element-of double-struck upper R Superscript upper N Baseline comma 3rd Row u comma v element-of upper D Superscript 1 comma 2 Baseline left-parenthesis double-struck upper R Superscript upper N Baseline right-parenthesis comma u comma v greater-than 0 in double-struck upper R Superscript upper N Baseline minus StartSet 0 EndSet comma EndLayout">

{

−
Δ
u
−

λ
1

|

x

|

2

u
=

u

2
∗

−
1

+
ν
α

u

α
−
1

v
β

,

x
∈

R

N

,

−
Δ
v
−

λ
2

|

x

|

2

v
=

v

2
∗

−
1

+
ν
β

u

α

v

β
−
1

,

x
∈

R

N

,

u
,

v
∈

D

1
,
2

(

R

N

)
,

u
,

v
>
0

in 

R

N

∖
{
0
}

,

\begin {cases}-\Delta u -\frac {\lambda _1}{|x|^2}u=u^{2^\ast -1}+ \nu \alpha u^{\alpha -1}v^\beta , \quad x\in \mathbb {R}^N,\\ -\Delta v -\frac {\lambda _2}{|x|^2}v=v^{2^\ast -1} + \nu \beta u^{\alpha }v^{\beta -1}, \quad x\in \mathbb {R}^N,\\ u,\, v\in D^{1, 2}(\mathbb {R}^N),\quad u,\, v>0\,\,\hbox {in $\mathbb {R}^N\setminus \{0\}$},\end {cases}

\]
where

N
≥
3

N\ge 3

,

λ
1

,

λ
2

∈
(
0
,

(
N
−
2

)
2

4

)

\lambda _1, \lambda _2\in (0, \frac {(N-2)^2}{4})

,

2
∗

=

2
N

N
−
2

2^\ast =\frac {2N}{N-2}

and

α
>
1
,
β
>
1

\alpha >1, \beta >1

satisfying

α
+
β
=

2
∗

\alpha +\beta =2^\ast

. This problem is related to coupled nonlinear Schrödinger equations with critical exponent for Bose-Einstein condensate. For different ranges of

N
N

,

α
\alpha

,

β
\beta

and

ν
>
0

\nu >0

, we obtain positive ground state solutions via some quite different variational methods, which are all radially symmetric. It turns out that the least energy level depends heavily on the relations among

α
,

β

\alpha , \,\beta

and

2
2

. Besides, for sufficiently small

ν
>
0

\nu >0

, positive solutions are also obtained via a variational perturbation approach. Note that the Palais-Smale condition cannot hold for any positive energy level, which makes the study via variational methods rather complicated.
Erratum to “A Connes-amenable, dual Banach algebra need not have a normal, virtual diagonal”
Authors: Runde Volker
Published: September 2014

In Trans. Amer. Math. Soc., vol. 358 (2006), pp. 391–402, we claimed that, for an amenable, non-compact

[

S
I
N

]

[\mathrm {SIN}]

-group

G
G

, the dual Banach algebra

W
A
P

(
G

)
∗

\mathcal {WAP}(G)^\ast

is Connes-amenable, but lacks a normal virtual diagonal. The proof presented contains a gap. In this erratum, we indicate how the faulty proof can be repaired.
Proteomic analysis and prediction of human phosphorylation sites in subcellular level reveal subcellular specificity
Authors: Chen Xiang , Shi Shao-Ping , Suo Sheng-Bao , Xu Hao-Dong , Qiu Jian-Ding
Published: September 2014

Motivation: Protein phosphorylation is the most common post-translational modification (PTM) regulating major cellular processes through highly dynamic and complex signaling pathways. Large-scale comparative phosphoproteomic studies have frequently been done on whole cells or organs by conventional bottom-up mass spectrometry approaches, i.e at the phosphopeptide level. Using this approach, there is no way to know from where the phosphopeptide signal originated. Also, as a consequence of the scale of these studies, important information on the localization of phosphorylation sites in subcellular compartments (SCs) is not surveyed.

Results: Here, we present a first account of the emerging field of subcellular phosphoproteomics where a support vector machine (SVM) approach was combined with a novel algorithm of discrete wavelet transform (DWT) to facilitate the identification of compartment-specific phosphorylation sites and to unravel the intricate regulation of protein phosphorylation. Our data reveal that the subcellular phosphorylation distribution is compartment type dependent and that the phosphorylation displays site-specific sequence motifs that diverge between SCs.

Availability and implementation: The method and database both are available as a web server at: http://bioinfo.ncu.edu.cn/SubPhos.aspx .

Contact:  jdqiu@ncu.edu.cn

Supplementary information:  Supplementary data are available at Bioinformatics online.
Using population data for assessing next-generation sequencing performance
Authors: Houniet Darren T. , Rahman Thahira J. , Al Turki Saeed , Hurles Matthew E. , Xu Yaobo , Goodship Judith , Keavney Bernard , Santibanez Koref Mauro
Published: September 2014

Motivation : During the past 4 years, whole-exome sequencing has become a standard tool for finding rare variants causing Mendelian disorders. In that time, there has also been a proliferation of both sequencing platforms and approaches to analyse their output. This requires approaches to assess the performance of different methods. Traditionally, criteria such as comparison with microarray data or a number of known polymorphic sites have been used. Here we expand such approaches, developing a maximum likelihood framework and using it to estimate the sensitivity and specificity of whole-exome sequencing data.

Results : Using whole-exome sequencing data for a panel of 19 individuals, we show that estimated sensitivity and specificity are similar to those calculated using microarray data as a reference. We explore the effect of frequency misspecification arising from using an inappropriately selected population and find that, although the estimates are affected, the rankings across procedures remain the same.

Availability and implementation : An implementation using Perl and R can be found at busso.ncl.ac.uk (Username: igm101; Password: Z1z1nts).

Contact : Darren.Houniet@ogt.com ; mauro.santibanez-koref@newcastle.ac.uk
Making novel proteins from pseudogenes
Authors: Shidhi P. R. , Suravajhala Prashanth , Nayeema Aysha , Nair Achuthsankar S. , Singh Shailja , Dhar Pawan K.
Published: September 2014

Motivation: Recently, we made synthetic proteins from non-coding DNA of Escherichia coli . Encouraged by this, we asked: can we artificially express pseudogenes into novel and functional proteins? What kind of structures would be generated? Would these proteins be stable? How would the organism respond to the artificial reactivation of pseudogenes?

Results: To answer these questions, we studied 16 full-length protein equivalents of pseudogenes. The sequence-based predictions indicated interesting molecular and cellular functional roles for pseudogene-derived proteins. Most of the proteins were predicted to be involved in the amino acid biosynthesis, energy metabolism, purines and pyrimidine biosynthesis, central intermediary metabolism, transport and binding. Interestingly, many of the pseudogene-derived proteins were predicted to be enzymes. Furthermore, proteins showed strong evidence of stable tertiary structures. The prediction scores for structure, function and stability were found to be favorable in most of the cases.

Impact: To our best knowledge, this is the first such report that predicts the possibility of making functional and stable proteins from pseudogenes. In future, it would be interesting to experimentally synthesize and validate these predictions.

Contact:  pawan.dhar@snu.edu.in

Supplementary information:  Supplementary data are available at Bioinformatics online.
Geodetic vertical velocities affected by recent rapid changes in polar motion
Authors: King Matt A. , Watson Christopher S.
Published: September 2014

Secular motion of Earth's rotation pole results in large-scale secular deformation of Earth. Here, we investigate the magnitude of the deformation that has resulted from the rapid motion of the rotation pole to the east since ∼2005. We show that geodetic (GNSS, DORIS, VLBI and SLR) estimates of vertical velocity since ∼2005 have been biased by up to ±0.38 mm yr–1 relative to the longer-term deformation pattern. The largest signals occur within regions that include the U.S. Pacific Coast, Europe and South Pacific islands where geodetic measurements provide essential measurements of tide-gauge vertical movement and important constraints on models of glacial isostatic adjustment. Consequently, geodetic vertical velocities based on recent data should not be interpreted as being identical to centennial or longer term vertical land movement. Since 2010 the effect is further amplified by the overprediction of the IERS polar motion model relative to the ongoing secular change in pole position—during this time geodetic vertical velocities based on the IERS pole tide model are not just biased relative to the long-term rates but also from actual post-2010 Earth deformation. For geophysical or reference frame studies seeking geodetic vertical velocities that are representative of decadal timescales, where interannual variation is considered noise, the correction for this non-linear effect is straightforward, requiring an elastic computation using a reference rate of polar motion that is linear over the timescales of interest.
Isolated Facial Vein Thrombophlebitis: A Variant of Lemierre Syndrome
Authors: Karnov Kirstine K.S. , Lilja-Fischer Jacob , Randrup Thomas Skov
Published: September 2014

Lemierre syndrome is a rare complication of acute tonsillitis. It is caused by the anaerobic bacterium Fusobacterium necrophorum and is characterized by bacteremia and septic thrombosis of the internal jugular vein. Dissemination of septic emboli may occur. The diagnosis can be difficult since different organs can be involved. We discuss a case of Lemierre syndrome in a 35-year-old woman with isolated thrombophlebitis of the facial vein and fusobacteria growth in blood culture. This case emphasizes the need for awareness of the condition.
The opposition effect of the asteroid 4 Vesta
Authors: Hasegawa Sunao , Miyasaka Seidai , Tokimasa Noritaka , Sogame Akito , Ibrahimov Mansur A. , Yoshida Fumi , Ozaki Shinobu , Abe Masanao , Ishiguro Masateru , Kuroda Daisuke
Published: September 2014

We present the results of photometric observations carried out with four small telescopes of the asteroid 4 Vesta in the B, RC, and z ′ bands at a minimum phase angle of 0$_{.}^{\circ}$1. The magnitudes, reduced to unit distance and zero phase angle, were MB(1, 1, 0) = 3.83 ± 0.01, $M_{R_{\rm C}}$(1, 1, 0) = 2.67 ± 0.01, and $M_{z^{\,\prime }}(1, 1, 0) = 3.03\,\pm \,0.01\:$mag. The absolute magnitude obtained from the IAU H − G function is ∼ 0.1 mag darker than the magnitude at a phase angle of 0° determined from the Shevchenko function and Hapke models with the coherent backscattering effect term. Our photometric measurements allowed us to derive geometric albedos of 0.35 in the B band, 0.41 in the RC band, and 0.31 in the z′ bands by using the Hapke model with the coherent backscattering effect term. Using the Hapke model, the porosity of the optically active regolith on Vesta was estimated to be ρ = 0.4–0.7, yielding a bulk density of 0.9–2.0 × 103 kg m−3. It is evident that the opposition effect for Vesta makes a contribution not only to the shadow-hiding effect, but also the coherent backscattering effect that appears from ∼ 1°. The amplitude of the coherent backscatter opposition effect for Vesta increases with a brightening of reflectance. By comparison with other solar system bodies, we suggest that multiple-scattering on an optically active scale may contribute to the amplitude of the coherent backscatter opposition effect (BC0).
Flavisolibacter rigui sp. nov., isolated from freshwater of an artificial reservoir and emended description of the genus Flavisolibacter
Authors: Baik Keun Sik , Kim Mi Sun , Lee Ji Hee , Lee Sang Suk , Im Wan-Taek , Seong Chi Nam
Published: September 2014

A non-motile and rod-shaped bacterium, designated strain 02SUJ3T, was isolated from freshwater collected from the Juam Reservoir (Republic of Korea). Cells were Gram-stain-negative, aerobic, oxidase-negative and catalase-positive. The major fatty acids were iso-C15 : 0, iso-C15 : 1 G and iso-C17 : 0 3-OH. The strain contained MK-7 as the major isoprenoid quinone. The main polar lipid was phosphatidylethanolamine. The DNA G+C content was 46.4 mol%. A phylogenetic tree based on 16S rRNA gene sequences showed that strain 02SUJ3T forms an independent lineage within the genus

Flavisolibacter

with low sequence similarity to

Flavisolibacter ginsengiterrae

Gsoil 492T and

Flavisolibacter ginsengisoli

Gsoil 643T (95.7 %). Phenotypic characteristics distinguished strain 02SUJ3T from members of the genus

Flavisolibacter

. On the basis of the evidence presented in this study, strain 02SUJ3T is considered to represent a novel species, for which the name Flavisolibacter
rigui sp. nov. is proposed. The type strain is 02SUJ3T ( = JCM 17515T = KCTC 23328T). An emended description of the genus

Flavisolibacter

is also provided.
darR and darS are regulatory genes that modulate 2-hexyl, 5-propyl resorcinol transcription in Pseudomonas chlororaphis PCL1606
Authors: Calderón Claudia E. , Carrión Víctor J. , de Vicente Antonio , Cazorla Francisco M.
Published: September 2014

Pseudomonas chlororaphisPCL1606 synthesizes the antifungal antibiotic 2-hexyl, 5-propyl resorcinol (HPR), which is crucial for the biocontrol of fungal soil-borne pathogens. The genetic basis for HPR production lies in thedargenes, which are directly involved in the biosynthesis of HPR. In the present study, we elucidated the genetic features of thedargenes. Reverse transcription PCR experiments revealed an independent organization of thedargenes, except fordarBC,which was transcribed as a polycistronic mRNA.In silicoanalysis of each gene revealed putative promoters and terminator sequences, validating the proposed gene arrangement. Moreover, experiments utilizing 5′ rapid amplification of cDNA ends were used to determine the transcriptional initiation sites for thedarA,darBC,darSanddarRgene promoters, and subsequently to confirm the functionality of these regions. The results of quantitative real-time PCR experiments indicated that biosyntheticdargenes were not only modulated through the global regulatorgacS, but also throughdarSanddarR. The interplay betweendarSanddarRrevealed transcriptional cross-inhibition. However, these results also showed that other regulatory parameters play a role in HPR production, such as the environmental conditions and additional regulatory genes.
SpeciesGeoCoder: Fast categorisation of species occurrences for analyses of biodiversity, biogeography, ecology and evolution
Authors: Töpel Mats , Calió Maria Fernanda , Zizka Alexander , Scharn Ruud , Silvestro Daniele , Antonelli Alexandre
Published: September 2014

Understanding the patterns and processes underlying the uneven distribution of biodiversity across space and time constitutes a major scientific challenge in evolutionary biology. With rapidly accumulating species occurrence data, there is an increasing need for making the process of coding species into operational units for biogeographic and evolutionary analyses faster, automated, transparent and reproducible. Here we present SpeciesGeoCoder, a free software package written in Python and R, that allows for easy coding of species into user-defined areas. These areas may be of any size and be purely geographical (i.e., polygons) such as political units, conservation areas, biomes, islands, biodiversity hotspots, and areas of endemism, but may also include altitudinal ranges. This flexibility allows scoring species into complex categories, such as those encountered in topographically and ecologically heterogeneous landscapes. In addition, SpeciesGeoCoder can be used to facilitate sorting and cleaning of occurrence data. The various outputs of SpeciesGeoCoder include quantitative biodiversity statistics, global and local distribution maps, and NEXUS files that can be directly used in many phylogeny-based applications for ancestral state reconstruction, investigations on biome evolution, and diversification rate analyses. Our simulations indicate that even datasets containing hundreds of millions of records can be analysed in relatively short time using a regular desktop computer. We exemplify the use of our program through two contrasting examples:i)inferring historical dispersal of birds across the Isthmus of Panama, separating lowlandvs.montane species and optimising the results onto a species-level, dated phylogeny; andii)exploring seasonal variations in the occurrence of 10 GPS-tracked individuals of moose (Alces alces) over one year in northern Sweden. These analyses show that SpeciesGeoCoder allows an easy, flexible and fast categorisation of species distribution data for various analyses in ecology and evolution, with potential use at different spatial, taxonomic and temporal scales.
The genetic ancestry of African, Latino, and European Americans across the United States
Authors: Bryc Katarzyna , Durand Eric Y. , Macpherson J. Michael , Reich David , Mountain Joanna L.
Published: September 2014

Over the past 500 years, North America has been the site of ongoing mixing of Native Americans, European settlers, and Africans brought largely by the Trans-Atlantic slave trade, shaping the early history of what became the United States. We studied the genetic ancestry of 5,269 self-described African Americans, 8,663 Latinos, and 148,789 European Americans who are 23andMe customers and show that the legacy of these historical interactions is visible in the genetic ancestry of present-day Americans. We document pervasive mixed ancestry and asymmetrical male and female ancestry contributions in all groups studied. We show that regional ancestry differences reflect historical events, such as early Spanish colonization, waves of immigration from many regions of Europe, and forced relocation of Native Americans within the US. This study sheds light on the fine-scale differences in ancestry within and across the United States, and informs our understanding of the relationship between racial and ethnic identities and genetic ancestry.
Corrosion behaviour of X52 steel in the presence of sulphite
Authors: C. Fatah Martin , C. Ismail Mokhtar , Ari-Wahjoedi Bambang
Published: September 2014

Purpose

– The purpose of this work was to study the corrosion behaviour of X52 steel in the presence of sulphite.

Design/methodology/approach

– The study was conducted in abiotic solutions containing species typical of sulphate-reducing bacteria (SRB) metabolism. Electrochemical techniques, i.e. linear polarization resistance (LPR), potentiodynamic and electrochemical impedance spectroscopy (EIS), were used to observe the corrosion kinetics and mechanism of X52 steel in the solution containing sulphite. Field emission scanning electron microscope (FESEM) and X-ray photoelectron spectroscopy (XPS) were used to characterize the corrosion products.

Findings

– LPR and EIS results showed that the addition of sulphite ions to the abiotic solutions increased the rate of X52 steel corrosion. The increase of corrosion rate was due to the increase in the cathodic reaction in the presence of sulphite. It was also observed that sulphite thinned the protective FeS film and caused corrosive species to adsorb on the surface, resulting in an increase in corrosion rate.

Originality/value

– This paper discusses the effects of sulphite on the corrosion behaviour of X52 steel in abiotic solution containing species typically produced by the SRB-type metabolic process. Irrespective of the presence of sulphide, sulphite is produced by SRB during their metabolic process. However, as far as is known, no published papers are available that discuss the effect of the presence of sulphite as one of the metabolic products of SRB.
Corrosion behavior of in situ (TiC-TiB2)p/AZ91 magnesium matrix composites in Harrison solution
Authors: Gobara Mohamed , Shamekh Mohamed
Published: September 2014

Purpose

– This paper aims to study both the mechanical properties and the corrosion behavior of the synthesized in situ (TiC-TiB2) particulates/AZ91 magnesium matrix composite and compare the results with that of the conventional AZ91D alloy.

Design/methodology/approach

– Scanning electron microscope (SEM) equipped with energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) were used to study the surface morphology and crystalline structure. Mechanical compression tests were used to investigate the mechanical performance according to ASTM E9-89a. The corrosion behavior of the synthesized magnesium alloy was examined using both electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques in dilute Harrison solutions.

Findings

– The microstructure of the Mg composite showed a uniform distribution of reinforcing phases. Also, the reinforcing phases were formed without residual intermediate phases. The addition of titanium and boron carbides not only enhanced the mechanical properties of the matrix but also improve its corrosion behavior.

Originality/value

– This is the first time that magnesium matrix composite has been to synthesized with TiC and TiB2 particulates starting from starting from Ti and B carbides powder without adding aluminium using practical and low-cost technique (in situ reactive infiltration technique). This paper studies the corrosion behavior of synthesized Mg matrix in dilute Harrison solution and compares the results with that of conventional AZ91D.