bluuebunny/crossref_metadata_2025 huggingface dataset:
Complex trait architecture: the pleiotropic model revisited
Authors: North T.-L. , Beaumont M. A.
Published: March 2015

There is currently much debate about how much the genetic heritability of complex traits is due to very rare alleles. This issue is important because it determines sampling strategies for genetic association studies. Several recent theoretical papers based on a pleiotropic model for trait evolution suggest that it is possible that a large proportion of the genetic variance could be explained by rare alleles. This model assumes that mutations with a large effect on fitness also tend to have large positive or negative effects on phenotypic traits. We show that conclusions based on standard diffusion results are generally applicable to simulations of whole genomes with overlapping generations in a finite population, although the variance contribution of rare alleles is somewhat smaller than theoretical predictions. We show that under many scenarios the pleiotropic model predicts trait distributions that are unrealistically leptokurtic. We argue that this imposes a limit on the relationship between fitness and trait effects.
The mealybug Phenacoccus solenopsis suppresses plant defense responses by manipulating JA-SA crosstalk
Authors: Zhang Peng-Jun , Huang Fang , Zhang Jin-Ming , Wei Jia-Ning , Lu Yao-Bin
Published: March 2015

Induced plant defenses against herbivores are modulated by jasmonic acid-, salicylic acid- and ethylene-signaling pathways. Although there is evidence that some pathogens suppress plant defenses by interfering with the crosstalk between different signaling pathways, such evidence is scarce for herbivores. Here, we demonstrate that the mealybug Phenacoccus solenopsis suppresses the induced defenses in tomato. We found that exogenous JA, but not SA, significantly decreased mealybug feeding time and reduced nymphal performance. In addition, constitutive activation of JA signaling in 35s::prosys plants reduced mealybug survival. These data indicate that the JA signaling pathway plays a key role in mediating the defense responses against P. solenopsis. We also found that mealybug feeding decreased JA production and JA-dependent defense gene expression, but increased SA accumulation and SA-dependent gene expression. In SA-deficient plants, mealybug feeding did not suppress but activated JA accumulation, indicating that the suppression of JA-regulated defenses depends on the SA signaling pathway. Mealybugs benefit from suppression of JA-regulated defenses by exhibiting enhanced nymphal performance. These findings confirm that P. solenopsis manipulates plants for its own benefits by modulating the JA-SA crosstalk and thereby suppressing induced defenses.
MicroRNA-derived Fragment Length Polymorphism Assay
Authors: Xie Xiaoping , Tang Fang , Yang Zhao , Zhang Yaoyi , Feng Zihao , Yang Yu , Wu Xiujin , Zhang Feifei , Zhu Jie , Xu Kai
Published: March 2015

MicroRNA (miRNA) studies are experiencing a transition from basic research applications to clinical applications. However, the lack of reliable and sensitive miRNA detection methods has become a bottleneck in the process. Here, we report an absolute quantification method based on the competitive PCR amplification of specific miRNAs and synthetic RNA spike-ins in a single reaction. RNA spike-ins are quantified as dynamic RNA copy number standards and are used to measure selected miRNAs free from the effects of intra-assay variables, including those from individual sample sources. Combined with the size differentiation power of capillary electrophoresis, the content of miRNAs was reproducibly measured, with verifiable detection limits of 10–46 copies over 5-log detection ranges. The direct measurements of miRNAs from 168 human serum samples and their considerable value as a diagnostic for bronchopneumonia and bronchiolitis demonstrate the potential of the assay in clinical applications.
Light-Emitting Devices Based on Top-down Fabricated GaAs Quantum Nanodisks
Authors: Higo Akio , Kiba Takayuki , Tamura Yosuke , Thomas Cedric , Takayama Junichi , Wang Yunpeng , Sodabanlu Hassanet , Sugiyama Masakazu , Nakano Yoshiaki , Yamashita Ichiro , Murayama Akihiro , Samukawa Seiji
Published: March 2015

Quantum dots photonic devices based on the III–V compound semiconductor technology offer low power consumption, temperature stability and high-speed modulation. We fabricated GaAs nanodisks (NDs) of sub-20-nm diameters by a top-down process using a biotemplate and neutral beam etching (NBE). The GaAs NDs were embedded in an AlGaAs barrier regrown by metalorganic vapor phase epitaxy (MOVPE). The temperature dependence of photoluminescence emission energies and the transient behavior were strongly affected by the quantum confinement effects of the embedded NDs. Therefore, the quantum levels of the NDs may be tuned by controlling their dimensions. We combined NBE and MOVPE in a high-throughput process compatible with industrial production systems to produce GaAs NDs with tunable optical characteristics. ND light emitting diode exhibited a narrow spectral width of 38 nm of high-intensity emission as a result of small deviation of ND sizes and superior crystallographic quality of the etched GaAs/AlGaAs layer.
Enhanced photocurrent production by bio-dyes of photosynthetic macromolecules on designed TiO2 film
Authors: Yu Daoyong , Wang Mengfei , Zhu Guoliang , Ge Baosheng , Liu Shuang , Huang Fang
Published: March 2015

The macromolecular pigment-protein complex has the merit of high efficiency for light-energy capture and transfer after long-term photosynthetic evolution. Here bio-dyes of A.platensis photosystem I (PSI) and spinach light-harvesting complex II (LHCII) are spontaneously sensitized on three types of designed TiO2 films, to assess the effects of pigment-protein complex on the performance of bio-dye sensitized solar cells (SSC). Adsorption models of bio-dyes are proposed based on the 3D structures of PSI and LHCII and the size of particles and inner pores in the TiO2 film. PSI shows its merit of high efficiency for captured energy transfer, charge separation and transfer in the electron transfer chain (ETC) and electron injection from FB to the TiO2 conducting band. After optimization, the best short current (JSC) and photoelectric conversion efficiency (η) of PSI-SSC and LHCII-SSC are 1.31 mA cm-2 and 0.47% and 1.51 mA cm-2 and 0.52%, respectively. The potential for further improvement of this PSI based SSC is significant and could lead to better utilization of solar energy.
Broadband Lamb Wave Trapping in Cellular Metamaterial Plates with Multiple Local Resonances
Authors: Zhao De-Gang , Li Yong , Zhu Xue-Feng
Published: March 2015

We have investigated the Lamb wave propagation in cellular metamaterial plates constructed by bending-dominated and stretch-dominated unit-cells with the stiffness differed by orders of magnitude at an ultralow density. The simulation results show that ultralight metamaterial plates with textured stubs deposited on the surface can support strong local resonances for both symmetric and anti-symmetric modes at low frequencies, where Lamb waves at the resonance frequencies are highly localized in the vibrating stubs. The resonance frequency is very sensitive to the geometry of textured stubs. By reasonable design of the geometry of resonant elements, we establish a simple loaded-bar model with the array of oscillators having a gradient relative density (or weight) that can support multiple local resonances, which permits the feasibility of a broadband Lamb wave trapping. Our study could be potentially significant in designing ingenious weight-efficient acoustic devices for practical applications, such as shock absorption, cushioning and vibrations traffic, etc.
Elucidating factors important for monovalent cation selectivity in enzymes: E. coli β-galactosidase as a model
Authors: Wheatley Robert W. , Juers Douglas H. , Lev Bogdan B. , Huber Reuben E. , Noskov Sergei Yu.
Published: March 2015

X-ray crystallography and computational simulations reveal novel mechanisms important for Na+/K+selectivity in enzymes.
Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) based nanocomposites: influence of the microstructure on the barrier properties
Authors: Crétois R. , Follain N. , Dargent E. , Soulestin J. , Bourbigot S. , Marais S. , Lebrun L.
Published: March 2015

P3HB4HB–C30B nanocomposites contain free, intercalated and aggregated nanoplatelets. Facilitated transport of CO2 due to the presence of ammonium groups on C30B. Concomitant and antagonist effects of nanoclays on water diffusion.
Construction of flexible photoelectrochemical solar cells based on ordered nanostructural BiOI/Bi2S3 heterojunction films
Authors: Fang Mingqing , Jia Huimin , He Weiwei , Lei Yan , Zhang Lizhi , Zheng Zhi
Published: March 2015

Ordered 2D nanostructural BiOI nanoflake arrays decorated with Bi2S3 nanospheres have been designed and in situ fabricated for the first time, to form BiOI/Bi2S3 bulk heterojunctions through a soft chemical route.
Noble metal alloy complex nanostructures: controllable synthesis and their electrochemical property
Authors: Liu Hui-ling , Nosheen Farhat , Wang Xun
Published: March 2015

From the perspective of noble metal alloy nanocrystals with complex structures, we highlight their controllable synthesis and improved electrochemical property.
Theoretical prediction of Am(iii)/Eu(iii) selectivity to aid the design of actinide-lanthanide separation agents
Authors: Bryantsev Vyacheslav S. , Hay Benjamin P.
Published: March 2015

A computational protocol capable of predicting the correct order of Am(iii)/Eu(iii) selectivity provides a theoretical basis for the design of more selective separation agents.
Superior CO2 adsorption from waste coffee ground derived carbons
Authors: Travis Will , Gadipelli Srinivas , Guo Zhengxiao
Published: March 2015

Utilising waste from spent coffee grounds KOH activated highly microporous carbons with surface areas of 2785 m2 g−1 and micropore volumes of 0.793 cm3 g−1 were synthesised that are capable of uptake capacities near 3 mmol g−1 at 50 °C and 1 bar.
Occurrence of non-equilibrium orthorhombic SnO2 phase and its effect in preferentially grown SnO2 nanowires for CO detection
Authors: Kumar Manjeet , Kumar Akshay , Abhyankar A. C.
Published: March 2015

Tin oxide nanowires (NWs) were deposited successfully on silicon substrate. Depending on the distance between the source and substrate, NWs exhibit either a single phase structure or a mixed phase structure, the latter exhibits enhanced sensitivity to CO detection.
Simple electrochemical synthesis of ultra-long silver telluride nanotubes
Authors: Park Kee-Ryung , Kim Seil , Myung Nosang V. , Kang Sung-Oong , Choa Yong-Ho
Published: March 2015

Ultra-long Ag2Te nanotubes could be electrochemically synthesized by post-electrodeposition of Te on electro-spun Ag nanofibers, in which Ag atoms diffuse into layers of Te and results in a morphology change from nanofibers to hollow nanotubes.
Total oxidation of isopropanol over manganese oxide modified ZSM-5 zeolite membrane catalysts
Authors: Ling Wang , Huiping Zhang , Ying Yan , Xinya Zhang
Published: March 2015

Manganese oxide modified ZSM-5 membrane catalysts were prepared for the catalytic combustion of a volatile organic compound (isopropanol) over a zeolite membrane reactor.
Preparation of novel carbon nanofibers with BiOBr and AgBr decoration for the photocatalytic degradation of rhodamine B
Authors: Jiang Guohua , Wei Zhen , Chen Hua , Du Xiangxiang , Li Lei , Liu Yongkun , Huang Qin , Chen Wenxing
Published: March 2015

Novel carbon nanofibers with BiOBr and AgBr decoration were prepared and exhibited a high efficiency for the photocatalytic degradation of RhB in aqueous solution and were convenient to separate from water.
Aptamer-based colorimetric biosensing of abrin using catalytic gold nanoparticles
Authors: Hu Jingting , Ni Pengjuan , Dai Haichao , Sun Yujing , Wang Yilin , Jiang Shu , Li Zhuang
Published: March 2015

A facile colorimetric aptasensor for abrin based on the peroxidase-like activity of gold nanoparticles was demonstrated for the first time.
Development of miniaturized solid phase microextraction of copper in serum using a micropipette tip in-syringe system combined with micro sampling flame atomic absorption spectrometry
Authors: Arain S. A. , Kazi T. G. , Afridi H. I. , Ullah N. , Arain M. S. , Panhwar A. H.
Published: March 2015

A new miniaturized solid phase microextraction (SPmE) method was developed for determining the trace levels of copper in hepatitis C patients.
A novel CO2- and SO2-tolerant dual phase composite membrane for oxygen separation
Authors: Cheng S. , Søgaard M. , Han L. , Zhang W. , Chen M. , Kaiser A. , Hendriksen P. V.
Published: March 2015

Here we report a novel, cheap, non-toxic, CO2- and SO2-stable dual phase composite oxygen transport membrane (Al0.02Ga0.02Zn0.96O1.02–Gd0.1Ce0.9O1.95−δ) for oxygen separation.
A dual-responsive supra-amphiphile based on a water-soluble pillar[7]arene and a naphthalene diimide-containing guest
Authors: Shao Li , Zhou Jiong , Hua Bin , Yu Guocan
Published: March 2015

A dual-responsive supra-amphiphile was firstly constructed based on a water-soluble pillar[7]arene and a naphthalene diimide-containing guest with a long alkyl chain and a trimethylammonium group. The morphology of the self-assembly formed from this supra-amphiphile could be adjusted by changing the solution pH or adding α-cyclodextrin.
Low-dimensional carbon spacers in surface plasmon-coupled emission with femtomolar sensitivity and 1000-fold fluorescence enhancements
Authors: S. Venkatesh , Badiya Pradeep Kumar , Ramamurthy Sai Sathish
Published: March 2015

We present low-dimensional carbon spacer engineering technology in surface plasmon-coupled emission for femtomolar sensitivity and fluorescence enhancements exceeding 1000 fold.
Asymmetric Suzuki–Miyaura cross-coupling of 1-bromo-2-naphthoates using the helically chiral polymer ligand PQXphos
Authors: Akai Yuto , Konnert Laure , Yamamoto Takeshi , Suginome Michinori
Published: March 2015

Axially chiral 1,1′-biaryl-2-carboxylates were synthesized via Suzuki–Miyaura cross-coupling of 2,4-dimethylpentan-3-yl 1-halo-2-naphthoates with arylboronic acids with single-handed helical polymer ligands PQXphos.
Nickel-catalysed P–C bond formation via P–H/C–CN cross coupling reactions
Authors: Zhang Ji-Shu , Chen Tieqiao , Yang Jia , Han Li-Biao
Published: March 2015

Nickel-catalysed P–H/C–CN cross coupling reactions take place efficiently under mild reaction conditions affording the corresponding sp2C–P bonds. This transformation provides a convenient method for the preparation of both arylphosphines and arylphosphine oxides from the readily available P–H compounds and arylnitriles.
Highly selective fluorescence imaging of zinc distribution in HeLa cells and Arabidopsis using a naphthalene-based fluorescent probe
Authors: Lee Ji Ha , Lee Jin Hyeok , Jung Sung Ho , Hyun Tae Kyung , Feng Mingxiao , Kim Jae-Yean , Lee Jae-Hong , Lee Hoyeon , Kim Jong Seung , Kang Chulhun , Kwon Ki-Young , Jung Jong Hwa
Published: March 2015

2-(N,N-Dimethylamino)naphthalene-based probe 1 was found to exhibit a dramatic enhancement in fluorescence upon addition of Zn2+, but not with any other metal ions.
Programmable Mg2+-dependent DNAzyme switch by the catalytic hairpin DNA assembly for dual-signal amplification toward homogeneous analysis of protein and DNA
Authors: Liu Shufeng , Cheng Chuanbin , Gong Hongwei , Wang Li
Published: March 2015

The catalytic hairpin DNA assembly-programmed Mg2+-dependent DNAzyme switch was proposed for dual-signal amplified detection of protein and DNA.
Ultra-sensitive ROS-responsive tellurium-containing polymers
Authors: Cao Wei , Gu Yuwei , Li Tianyu , Xu Huaping
Published: March 2015

Tellurium-containing polymer micelles are responsive to 100 μM H2O2 or 2 Gy gamma radiation, enabling the development of ultra-sensitive ROS-eliminating materials.
Thiophene synthesis via 1,1-carboboration
Authors: Eller Christina , Kehr Gerald , Daniliuc Constantin G. , Stephan Douglas W. , Erker Gerhard
Published: March 2015

Reaction of bis(tert-butylethynyl)sulfide with the boron Lewis acid reagents X–B(C6F5)2 (X = CH3, Cl, C6F5) in pentane at r.t. gave the respective borylated thiophenes in a sequence of 1,1-carboboration reactions.
Porous corundum-type In2O3 nanoflowers: controllable synthesis, enhanced ethanol-sensing properties and response mechanism
Authors: Gao Liping , Ren Fumin , Cheng Zhixuan , Zhang Yuan , Xiang Qun , Xu Jiaqiang
Published: March 2015

Porous rhombohedral In2O3 (corundum-type In2O3, rh-In2O3) with a morphology of uniform nanoflowers was fabricated by using a mild, facile solvent-thermal method.
One step synthesis of hierarchical dendritic Pt nanostructures with a concave Pt octahedron building unit via simultaneous vertex growth and facet etching
Authors: Yoon Donghwan , Bang Sulgi , Jin Haneul , Baik Hionsuck , Lee Kwangyeol
Published: March 2015

The one step synthesis of hierarchical dendritic Pt nanostructures with a concave Pt octahedron building unit is demonstrated.
Structural evolution of an intermetallic Pd–Zn catalyst selective for propane dehydrogenation
Authors: Gallagher James R. , Childers David J. , Zhao Haiyan , Winans Randall E. , Meyer Randall J. , Miller Jeffrey T.
Published: March 2015

Formation of PdZn intermetallic nanoalloys selective for propane dehydrogenation tracked using in situ synchrotron XRD.
Very low amount of TiO2 on N-doped carbon nanotubes significantly improves oxygen reduction activity and stability of supported Pt nanoparticles
Authors: Zhao Anqi , Masa Justus , Xia Wei
Published: March 2015

Highly dispersed TiO2 on nitrogen-doped carbon nanotubes is used to tackle the carbon corrosion problem when used as support for Pt in electrocatalysis.
Theoretical study of electronic and tribological properties of h-BNC2/graphene, h-BNC2/h-BN and h-BNC2/h-BNC2bilayers
Authors: Ansari Narjes , Nazari Fariba , Illas Francesc
Published: March 2015

Density functional theory methods are used to investigate the interlayer sliding energy landscape, binding energy and interlayer spacing between h-BNC2/graphene (I), h-BNC2/h-BN (II) and h-BNC2/h-BNC2(III) bilayer structures.
Comparison of the plasmonic performances between lithographically fabricated and chemically grown gold nanorods
Authors: Shao Lei , Tao Yuting , Ruan Qifeng , Wang Jianfang , Lin Hai-Qing
Published: March 2015

The plasmonic performances of lithographic and chemical gold nanorods are quantitatively examined and compared through both experiments and electrodynamic simulations.
Optimisation of preparation method for Pd doped Cu/Al2O3 catalysts for selective acetylene hydrogenation
Authors: McCue Alan J. , Shepherd Ashley M. , Anderson James A.
Published: March 2015

3 preparation methods were explored for preparing CuPd catalysts for selective acetylene hydrogenation leading to materials which were selective and active at lower temperatures than normally observed for Cu catalysts.
Utilisation of water soluble iridium catalysts for signal amplification by reversible exchange
Authors: Fekete M. , Gibard C. , Dear G. J. , Green G. G. R. , Hooper A. J. J. , Roberts A. D. , Cisnetti F. , Duckett S. B.
Published: March 2015

The catalytic hyperpolarisation of pyridine, 3-hydroxypyridine and oxazol by the Signal Amplification By Reversible Exchange (SABRE) process is achieved by a series of water soluble iridium phosphine and N-heterocyclic carbene dihydride complexes.
A highly sensitive room temperature H2S gas sensor based on SnO2multi-tube arrays bio-templated from insect bristles
Authors: Tian Junlong , Pan Feng , Xue Ruiyang , Zhang Wang , Fang Xiaotian , Liu Qinglei , Wang Yuhua , Zhang Zhijian , Zhang Di
Published: March 2015

A tin oxide multi-tube array with a parallel effect was fabricated, which exhibited high sensitivity to H2S gas at room temperature.
Band alignment and enhanced photocatalytic activation of α/β-Bi2O3 heterojunctions via in situ phase transformation
Authors: Shan Lianwei , Wang Guilin , Li Dan , San Xingyuan , Liu Lizhu , Dong Limin , Wu Ze
Published: March 2015

The α/β-Bi2O3 heterojunction prepared by an in situ phase transformation technique shows effective band alignment and high photocatalytic activity.
Exciton dynamics and annihilation in WS2 2D semiconductors
Authors: Yuan Long , Huang Libai
Published: March 2015

We systematically investigate the exciton dynamics in monolayered, bilayered, and trilayered WS2 two-dimensional (2D) crystals by time-resolved photoluminescence (TRPL) spectroscopy.
Binding-induced, turn-on fluorescence of the EGFR/ERBB kinase inhibitor, lapatinib
Authors: Wilson James N. , Liu Wenjun , Brown Adrienne S. , Landgraf Ralf
Published: March 2015

The photophysical properties, fluorescence imaging, cellular uptake and distribution of lapatinib, an EGFR/ERBB inhibitor are reported.
Gold nanoparticles decorated on a graphene-periodic mesoporous silica sandwich nanocomposite as a highly efficient and recyclable heterogeneous catalyst for catalytic applications
Authors: Movahed Siyavash Kazemi , Shariatipour Monire , Dabiri Minoo
Published: March 2015

Ultra-small Au nanoparticles (Au NPs) were immobilized on HS-functionalized sandwich-like periodic mesoporous silica (PMS) coated graphene (G) to form the novel nanocomposite catalyst Au NPs@HS-G-PMS.
Microporous carbonaceous adsorbents for CO2separation via selective adsorption
Authors: Zhao Yunfeng , Liu Xin , Han Yu
Published: March 2015

This article reviews recently developed microporous carbonaceous adsorbents including inorganic carbons and organic polymers for CO2separationviaselective adsorption.
Solution-processed efficient deep-blue fluorescent organic light-emitting diodes based on novel 9,10-diphenyl-anthracene derivatives
Authors: Zhang Zhaohang , Jiang Wei , Ban Xinxin , Yang Min , Ye Shanghui , Huang Bin , Sun Yueming
Published: March 2015

Carbazole substituted 9,10-diphenyl-anthracene derivatives used in deep-blue fluorescence OLED materials with excellent performance.
Structural and thermodynamic basis of interaction of the putative anticancer agent chelerythrine with single, double and triple-stranded RNAs
Authors: Basu Pritha , Kumar Gopinatha Suresh
Published: March 2015

Interaction of chl with poly(uau), poly(au) and poly(u).
3D-printed alginate/phenamil composite scaffolds constituted with microsized core–shell struts for hard tissue regeneration
Authors: Lee KyoungHo , Seo Cho-Rong , Ku Jin-Mo , Lee Hyeongjin , Yoon Hyeon , Lee JaeHwan , Chun Wook , Park Kye Won , Kim GeunHyung
Published: March 2015

A new composite scaffold consisting of poly(ε-caprolactone), alginate, and phenamil was manufactured by a combined process, 3D-printing and coating process, for hard tissue regeneration.
Synthesis and characterization of gold complexes with pyridine-based SNS ligands and as homogeneous catalysts for reduction of 4-nitrophenol
Authors: Jia Wei-Guo , Dai Yuan-Chen , Zhang Hai-Ning , Lu Xiaojing , Sheng En-Hong
Published: March 2015

Three gold complexes efficiently catalyze 4-nitrophenol reduction to 4-nitroaniline in the presence of NaBH4 under homogeneous conditions in water.
Fabrication of nanofibres with azopyridine compounds in various acids and solvents
Authors: Chen Yinjie , Quan Maohua , Yu Haifeng , Zhang Lanying , Yang Huai , Lu Yunfeng
Published: March 2015

Supramolecular self-organization behaviours of one azopyridine compound were systematically studied in a series of inorganic acids and various organic solvents.
Physioelectrochemical and DFT investigation of metal oxide/p-type conductive polymer nanoparticles as an efficient catalyst for the electrocatalytic oxidation of methanol
Authors: Ehsani Ali , Mahjani Mohammad Ghasem , Babaei Ferydon , Mostaanzadeh Hossein
Published: March 2015

Poly tyramine–NiO as an efficient electrocatalyst was prepared by in situ electropolymerization of tyramine in the presence of the SDS under ultrasonic irradiation.
Synthesis of micro/nano-structured Mn3O4 for supercapacitor electrode with excellent rate performance
Authors: Qiao Yuqing , Sun Qujiang , Cui Haiying , Wang Debiao , Yang Fengyu , Wang Xianhui
Published: March 2015

Micro/nano-structured Mn3O4 with an open three-dimensional flower-like morphology were fabricated by a facile solvothermal approach using hexadecyltrimethylammonium bromide as a surfactant and CH3CH2OH as a solvent.
Direct trifluoromethylation of imidazoheterocycles in a recyclable medium at room temperature
Authors: Ji Xiao-Ming , Wei Liang , Chen Fan , Tang Ri-Yuan
Published: March 2015

Regioselective C–H trifluoromethylation of imidazoheterocycles with Langlois' reagent in a recyclable mixed medium of 1-butyl-3-methylimidazoliumtetrafluoroborate ([Bmim]BF4) and water at room temperature has been developed.
Neurotoxin-directed synthesis and in vitro evaluation of Au nanoclusters
Authors: Sun Zhengbo , Zhang Wenlu , Zhang Pengfei , Gao Duyang , Gong Ping , Yu Xue-Feng , Wu Yingliang , Cao Zhijian , Li Wenxin , Cai Lintao
Published: March 2015

A glioma-specific theranostic agent is prepared by using Chlorotoxin fusion protein to direct the synthesis of Au nanoclusters, which exhibit bright fluorescence and high specificity to target and treat glioma cells.
Designing 3D graphene networks via a 3D-printed Ni template
Authors: Yang Zhuxian , Yan Chunze , Liu Jinhui , Chabi Sakineh , Xia Yongde , Zhu Yanqiu
Published: March 2015

It is highly desirable to design and control the properties of 3D graphene networks with preferred shapes, lengths, diameters of the trusses so as to add new functionalities.
Cu(ClO4)2·6H2O catalyzed solvent free per-O-acetylation and sequential one-pot conversions of sugars to thioglycosides
Authors: Chatterjee Debnath , Paul Abhijit , Rajkamal Rajkamal , Yadav Somnath
Published: March 2015

The solvent free per-O-acetylation of various reducing and non-reducing sugars has been carried out using stoichiometric amounts of acetic anhydride and copper(ii) perchlorate hexahydrate as the catalyst.
A facilely designed, highly efficient green synthetic strategy of a peony flower-like SO42−–SnO2-fly ash nano-catalyst for the three component synthesis of a serendipitous product with dimedone in water
Authors: Thirumurthy Kannan , Thirunarayanan Ganesamoorthy
Published: March 2015

A facilely designed green synthetic strategy of a peony flower-like SO42−–SnO2-fly ash nano-catalyst for the synthesis of an unusual product in water.
Adhesive contact of a rigid circular cylinder to a soft elastic substrate – the role of surface tension
Authors: Liu Tianshu , Jagota Anand , Hui Chung-Yuen
Published: March 2015

This article studies the effects of surface tension on the adhesive contact mechanics of a long rigid cylinder on an infinite half space comprising an incompressible elastic material.
Syneresis and delayed detachment in agar plates
Authors: Divoux Thibaut , Mao Bosi , Snabre Patrick
Published: March 2015

Gels in agar plates often lose contact with the dish sidewall as a result of syneresis and water evaporation. We rationalize such delayed and sudden detachment by means of direct observations and speckle correlation spectroscopy.
Efficient hydrogen evolution reaction catalyzed by molybdenum carbide and molybdenum nitride nanocatalysts synthesized via the urea glass route
Authors: Ma Liang , Ting Louisa Rui Lin , Molinari Valerio , Giordano Cristina , Yeo Boon Siang
Published: March 2015

Hydrogen evolution was performed in KOH and H2SO4 electrolytes using α-Mo2C and γ-Mo2N synthesized by the ‘urea glass’ route. α-Mo2C shows excellent performance especially in KOH.
Anatase TiO2nanocubes for fast and durable sodium ion battery anodes
Authors: Yang Xuming , Wang Chao , Yang Yingchang , Zhang Yan , Jia Xinnan , Chen Jun , Ji Xiaobo
Published: March 2015

Anatase TiO2nanocubes were employed as sodium ion battery anodes and they delivered an outstanding rate and cycling performance after an interesting activation process.
Engineering hollow mesoporous silica nanocontainers with molecular switches for continuous self-healing anticorrosion coating
Authors: Chen Tao , Chen Renpeng , Jin Zhong , Liu Jie
Published: March 2015

We report a new light-responsive and self-healing anticorrosion coating by incorporating hollow nanocontainers with smart molecular switches.
A stable RNA G-quadruplex within the 5′-UTR of Arabidopsis thaliana ATR mRNA inhibits translation
Authors: Kwok Chun Kit , Ding Yiliang , Shahid Saima , Assmann Sarah M. , Bevilacqua Philip C.
Published: March 2015

Guanine quadruplex structures (GQSs) play important roles in the regulation of gene expression and cellular processes. Recent studies provide strong evidence for the formation and function of DNA and RNA GQSs in human cells. However, whether GQSs form and are functional in plants remains essentially unexplored. On the basis of circular dichroism (CD)-detected titration, UV-detected melting, in-line probing (ILP) and reporter gene assay studies, we report the first example of a plant RNA GQS that inhibits translation. This GQS is located within the 5′-UTR of the ATAXIA TELANGIECTASIA-MUTATED AND RAD3-RELATED (ATR) mRNA of Arabidopsis thaliana (mouse-ear cress). We show that this GQS is highly stable and is thermodynamically favoured over a competing hairpin structure in the 5′-UTR at physiological K+ and Mg2+ concentrations. Results from ILP reveal the secondary structure of the RNA and support formation of the GQS in vitro in the context of the complete 5′-UTR. Transient reporter gene assays performed in living plants reveal that the GQS inhibits translation but not transcription, implicating this GQS as a translational repressor in vivo. Our results provide the first complete demonstration of the formation and function of a regulatory RNA GQS in plants and open new avenues to explore potential functional roles of GQS in the plant kingdom.
Glycosynthesis in a waterworld: new insight into the molecular basis of transglycosylation in retaining glycoside hydrolases
Authors: Bissaro Bastien , Monsan Pierre , Fauré Régis , O’Donohue Michael J.
Published: March 2015

Carbohydrates are ubiquitous in Nature and play vital roles in many biological systems. Therefore the synthesis of carbohydrate-based compounds is of considerable interest for both research and commercial purposes. However, carbohydrates are challenging, due to the large number of sugar subunits and the multiple ways in which these can be linked together. Therefore, to tackle the challenge of glycosynthesis, chemists are increasingly turning their attention towards enzymes, which are exquisitely adapted to the intricacy of these biomolecules. In Nature, glycosidic linkages are mainly synthesized by Leloir glycosyltransferases, but can result from the action of non-Leloir transglycosylases or phosphorylases. Advantageously for chemists, non-Leloir transglycosylases are glycoside hydrolases, enzymes that are readily available and exhibit a wide range of substrate specificities. Nevertheless, non-Leloir transglycosylases are unusual glycoside hydrolases in as much that they efficiently catalyse the formation of glycosidic bonds, whereas most glycoside hydrolases favour the mechanistically related hydrolysis reaction. Unfortunately, because non-Leloir transglycosylases are almost indistinguishable from their hydrolytic counterparts, it is unclear how these enzymes overcome the ubiquity of water, thus avoiding the hydrolytic reaction. Without this knowledge, it is impossible to rationally design non-Leloir transglycosylases using the vast diversity of glycoside hydrolases as protein templates. In this critical review, a careful analysis of literature data describing non-Leloir transglycosylases and their relationship to glycoside hydrolase counterparts is used to clarify the state of the art knowledge and to establish a new rational basis for the engineering of glycoside hydrolases.
Directed evolution of cytochrome P450 enzymes for biocatalysis: exploiting the catalytic versatility of enzymes with relaxed substrate specificity
Authors: Behrendorff James B.Y.H. , Huang Weiliang , Gillam Elizabeth M.J.
Published: March 2015

Cytochrome P450 enzymes are renowned for their ability to insert oxygen into an enormous variety of compounds with a high degree of chemo- and regio-selectivity under mild conditions. This property has been exploited in Nature for an enormous variety of physiological functions, and representatives of this ancient enzyme family have been identified in all kingdoms of life. The catalytic versatility of P450s makes them well suited for repurposing for the synthesis of fine chemicals such as drugs. Although these enzymes have not evolved in Nature to perform the reactions required for modern chemical industries, many P450s show relaxed substrate specificity and exhibit some degree of activity towards non-natural substrates of relevance to applications such as drug development. Directed evolution and other protein engineering methods can be used to improve upon this low level of activity and convert these promiscuous generalist enzymes into specialists capable of mediating reactions of interest with exquisite regio- and stereo-selectivity. Although there are some notable successes in exploiting P450s from natural sources in metabolic engineering, and P450s have been proven repeatedly to be excellent material for engineering, there are few examples to date of practical application of engineered P450s. The purpose of the present review is to illustrate the progress that has been made in altering properties of P450s such as substrate range, cofactor preference and stability, and outline some of the remaining challenges that must be overcome for industrial application of these powerful biocatalysts.
Determinants of oligosaccharide specificity of the carbohydrate-binding modules of AMP-activated protein kinase
Authors: Mobbs Jesse I. , Koay Ann , Di Paolo Alex , Bieri Michael , Petrie Emma J. , Gorman Michael A. , Doughty Larissa , Parker Michael W. , Stapleton David I. , Griffin Michael D.W. , Gooley Paul R.
Published: March 2015

AMP-activated protein kinase (AMPK) is an αβγ heterotrimer that is important in regulating energy metabolism in all eukaryotes. The β-subunit exists in two isoforms (β1 and β2) and contains a carbohydrate-binding module (CBM) that interacts with glycogen. The two CBM isoforms (β1- and β2-CBM) are near identical in sequence and structure, yet show differences in carbohydrate-binding affinity. β2-CBM binds linear carbohydrates with 4-fold greater affinity than β1-CBM and binds single α1,6-branched carbohydrates up to 30-fold tighter. To understand these affinity differences, especially for branched carbohydrates, we determined the NMR solution structure of β2-CBM in complex with the single α1,6-branched carbohydrate glucosyl-β-cyclodextrin (gBCD) which supported the dynamic nature of the binding site, but resonance broadening prevented defining where the α1,6 branch bound. We therefore solved the X-ray crystal structures of β1- and β2-CBM, in complex with gBCD, to 1.7 and 2.0 Å (1 Å=0.1 nm) respectively. The additional threonine (Thr101) of β2-CBM expands the size of the surrounding loop, creating a pocket that accommodates the α1,6 branch. Hydrogen bonds are formed between the α1,6 branch and the backbone of Trp99 and Lys102 side chain of β2-CBM. In contrast, the α1,6 branch could not be observed in the β1-CBM structure, suggesting that it does not form a specific interaction. The orientation of gBCD bound to β1- and β2-CBM is supported by thermodynamic and kinetic data obtained through isothermal titration calorimetry (ITC) and NMR. These results suggest that AMPK containing the muscle-specific β2-isoform may have greater affinity for partially degraded glycogen.
SRY gene transferred by extracellular vesicles accelerates atherosclerosis by promotion of leucocyte adherence to endothelial cells
Authors: Cai Jin , Guan Weiwei , Tan Xiaorong , Chen Caiyu , Li Liangpeng , Wang Na , Zou Xue , Zhou Faying , Wang Jialiang , Pei Fang , Chen Xinjian , Luo Hao , Wang Xinquan , He Duofen , Zhou Lin , Jose Pedro A. , Zeng Chunyu
Published: March 2015

We set out to investigate whether and how SRY (sex-determining region, Y) DNAs in plasma EVs (extracellular vesicles) is involved in the pathogenesis of atherosclerosis. PCR and gene sequencing found the SRY gene fragment in plasma EVs from male, but not female, patients; EVs from male patients with CAD (coronary artery disease) had a higher SRY GCN (gene copy number) than healthy subjects. Additional studies found that leucocytes, the major source of plasma EVs, had higher SRY GCN and mRNA and protein expression in male CAD patients than controls. After incubation with EVs from SRY-transfected HEK (human embryonic kidney)-293 cells, monocytes (THP-1) and HUVECs (human umbilical vein endothelial cells), which do not endogenously express SRY protein, were found to express newly synthesized SRY protein. This resulted in an increase in the adherence factors CD11-a in THP-1 cells and ICAM-1 (intercellular adhesion molecule 1) in HUVECs. EMSA showed that SRY protein increased the promoter activity of CD11-a in THP-1 cells and ICAM-1 in HUVECs. There was an increase in THP-1 cells adherent to HUVECs after incubation with SRY-EVs. SRY DNAs transferred from EVs have pathophysiological significance in vivo; injection of SRY EVs into ApoE−/− (apolipoprotein-knockout) mice accelerated atherosclerosis. The SRY gene in plasma EVs transferred to vascular endothelial cells may play an important role in the pathogenesis of atherosclerosis; this mechanism provides a new approach to the understanding of inheritable CAD in men.
Surface thermodynamics of planar, cylindrical, and spherical vapour-liquid interfaces of water
Authors: Lau Gabriel V. , Ford Ian J. , Hunt Patricia A. , Müller Erich A. , Jackson George
Published: March 2015

The test-area (TA) perturbation approach has been gaining popularity as a methodology for the direct computation of the interfacial tension in molecular simulation. Though originally implemented for planar interfaces, the TA approach has also been used to analyze the interfacial properties of curved liquid interfaces. Here, we provide an interpretation of the TA method taking the view that it corresponds to the change in free energy under a transformation of the spatial metric for an affine distortion. By expressing the change in configurational energy of a molecular configuration as a Taylor expansion in the distortion parameter, compact relations are derived for the interfacial tension and its energetic and entropic components for three different geometries: planar, cylindrical, and spherical fluid interfaces. While the tensions of the planar and cylindrical geometries are characterized by first-order changes in the energy, that of the spherical interface depends on second-order contributions. We show that a greater statistical uncertainty is to be expected when calculating the thermodynamic properties of a spherical interface than for the planar and cylindrical cases, and the evaluation of the separate entropic and energetic contributions poses a greater computational challenge than the tension itself. The methodology is employed to determine the vapour-liquid interfacial tension of TIP4P/2005 water at 293 K by molecular dynamics simulation for planar, cylindrical, and spherical geometries. A weak peak in the curvature dependence of the tension is observed in the case of cylindrical threads of condensed liquid at a radius of about 8 Å, below which the tension is found to decrease again. In the case of spherical drops, a marked decrease in the tension from the planar limit is found for radii below ∼ 15 Å; there is no indication of a maximum in the tension with increasing curvature. The vapour-liquid interfacial tension tends towards the planar limit for large system sizes for both the cylindrical and spherical cases. Estimates of the entropic and energetic contributions are also evaluated for the planar and cylindrical geometries and their magnitudes are in line with the expectations of our simple analysis.
Soliton solutions and chaotic motions of the Zakharov equations for the Langmuir wave in the plasma
Authors: Zhen Hui-Ling , Tian Bo , Wang Yu-Feng , Liu De-Yin
Published: March 2015

For the interaction between the high-frequency Langmuir waves and low-frequency ion-acoustic waves in the plasma, the Zakharov equations are studied in this paper. Via the Hirota method, we obtain the soliton solutions, based on which the soliton propagation is presented. It is found that with λ increasing, the amplitude of u decreases, whereas that of v remains unchanged, where λ is the ion-acoustic speed, u is the slowly-varying envelope of the Langmuir wave, and v is the fluctuation of the equilibrium ion density. Both the head-on and bound-state interactions between the two solitons are displayed. We observe that with λ decreasing, the interaction period of u decreases, while that of v keeps unchanged. It is found that the Zakharov equations cannot admit any chaotic motions. With the external perturbations taken into consideration, the perturbed Zakharov equations are studied for us to see the associated chaotic motions. Both the weak and developed chaotic motions are investigated, and the difference between them roots in the relative magnitude of the nonlinearities and perturbations. The chaotic motions are weakened with λ increasing, or else, strengthened. Periodic motion appears when the nonlinear terms and external perturbations are balanced. With such a balance kept, one period increases with λ increasing.
Magnetic tunnel junction based out-of-plane field sensor with perpendicular magnetic anisotropy in reference layer
Authors: Lee Y. C. , Chao C. T. , Li L. C. , Suen Y. W. , Horng Lance , Wu Te-Ho , Chang C. R. , Wu J. C.
Published: March 2015

A magnetic tunnel junction (MTJ) with orthogonal magnetic anisotropy and consisting of Ta X/Co40Fe40B20 1.2 (reference)/MgO 2.0/Co20Fe60B20 2.3 (sensing)/Ta 5/Ru 5 (thickness in nanometers), where X ranges from 15 to 30, is proposed and investigated in response to the demand for out-of-plane field sensors. The reference layer with perpendicular magnetic anisotropy (PMA) demonstrates tuneable coercivity ranging from 72 Oe to 175 Oe. The sensing layer exhibits in-plane anisotropy with the avoidance of exchange coupling from the PMA reference layer because of a thick MgO barrier layer. The magnetization reversal behavior of micron scale devices not only corresponds well to the sheet film, but is also independent in terms of shape and size. The magnetoresistance curve exhibits a ratio of ∼27% in the presence of a perpendicular field and is insensitive to the in-plane field. For perpendicular field sensing, the dynamic range with a sensitivity of ∼0.3%/Oe can achieve ±25 Oe with a coercive field of less than 3 Oe. Additionally, even when bias is applied up to 9.1 mV, magnetic fluctuation still stays below 0.15 mOe.
Ideal square quantum wells achieved in AlGaN/GaN superlattices using ultrathin blocking-compensation pair
Authors: Chen Xiaohong , Xu Hongmei , Lin Na , Xu Fuchun , Chen Hangyang , Cai Duanjun , Kang Junyong
Published: March 2015

A technique for achieving square-shape quantum wells (QWs) against the intrinsic polar discontinuity and interfacial diffusion through self-compensated pair interlayers is reported. Ultrathin low-and-high % pair interlayers that have diffusion-blocking and self-compensation capacities is proposed to resist the elemental diffusion at nanointerfaces and to grow the theoretically described abrupt rectangular AlGaN/GaN superlattices by metal-organic chemical vapor deposition. Light emission efficiency in such nanostructures is effectively enhanced and the quantum-confined Stark effect could be partially suppressed. This concept could effectively improve the quality of ultrathin QWs in functional nanostructures with other semiconductors or through other growth methods.
Time-resolved ion velocity distribution in a cylindrical Hall thruster: Heterodyne-based experiment and modeling
Authors: Diallo A. , Keller S. , Shi Y. , Raitses Y. , Mazouffre S.
Published: March 2015

Time-resolved variations of the ion velocity distribution function (IVDF) are measured in the cylindrical Hall thruster using a novel heterodyne method based on the laser-induced fluorescence technique. This method consists in inducing modulations of the discharge plasma at frequencies that enable the coupling to the breathing mode. Using a harmonic decomposition of the IVDF, one can extract each harmonic component of the IVDF from which the time-resolved IVDF is reconstructed. In addition, simulations have been performed assuming a sloshing of the IVDF during the modulation that show agreement between the simulated and measured first order perturbation of the IVDF.
A figure of merit for focusing metasurfaces
Authors: Saeidi Chiya , van der Weide Daniel
Published: March 2015

We propose and define a figure of merit (FoM) for designing focusing metasurfaces by establishing a reference case. We emphasize the important role of the focal point concept for obtaining the desired functionality. We suggest several design considerations along with the FoM for a careful design and performance evaluation of the prototype, without which the focusing property of a designed metasurface may be only slightly better than that of a planar scattering surface.
Molecular ring rotation in solid ferrocene revisited
Authors: Appel Markus , Frick Bernhard , Spehr Tinka Luise , Stühn Bernd
Published: March 2015

We report on quasielastic neutron spectroscopy experiments on ferrocene (bis(η5-cyclopentadienyl)iron) in its three different crystalline phases: the disordered monoclinic crystalline phase (T > 164 K), the metastable triclinic phase (T < 164 K), and the stable orthorhombic phase (T < 250 K). The cyclopentadienyl rings in ferrocene are known to undergo rotational reorientations for which the analysis of our large data set suggests partially a revision of the known picture of the dynamics and allows for an extension and completion of previous studies. In the monoclinic phase, guided by structural information, we propose a model for rotational jumps among non-equivalent sites in contrast to the established 5-fold jump rotation model. The new model takes the dynamical disorder into account and allows the cyclopentadienyl rings to reside in two different configurations which are found to be twisted by an angle of approximately 30°. In the triclinic phase, our analysis demands the use of a 2-ring model accounting for crystallographically independent sites with different barriers to rotation. For the orthorhombic phase of ferrocene, we confirm a significantly increased barrier of rotation using neutron backscattering spectroscopy. Our data analysis includes multiple scattering corrections and presents a novel approach of simultaneous analysis of different neutron scattering data by combining elastic and inelastic fixed window temperature scans with energy spectra, providing a very robust and reliable mean of extracting the individual activation energies of overlapping processes.
Dimensional transition of energy cascades in stably stratified forced thin fluid layers
Authors: Sozza A. , Boffetta G. , Muratore-Ginanneschi P. , Musacchio S.
Published: March 2015

We study the effects of a stable density stratification on the turbulent dynamics of thin fluid layers forced at intermediate scales. By means of a set of high-resolution numerical simulations, performed within the Boussinesq approximation, we investigate how the stratification and confinement affect the mechanisms of kinetic and potential energy transfer. The detailed analysis of the statistics of the energy-dissipation rates and energy-exchange rates and of the spectral fluxes of potential and kinetic energy shows that stratification provides a new channel for the energy transfer towards small scales which reduces the large-scale flux of kinetic energy. We also discuss the role of vortex stretching and enstrophy flux in the transfer of kinetic energy into potential energy at small scales.