bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantitative electron phase imaging with high sensitivity and an unlimited field of view
Authors: Maiden A. M. , Sarahan M. C. , Stagg M. D. , Schramm S. M. , Humphry M. J.
Published: October 2015

As it passes through a sample, an electron beam scatters, producing an exit wavefront rich in information. A range of material properties, from electric and magnetic field strengths to specimen thickness, strain maps and mean inner potentials, can be extrapolated from its phase and mapped at the nanoscale. Unfortunately, the phase signal is not straightforward to obtain. It is most commonly measured using off-axis electron holography, but this is experimentally challenging, places constraints on the sample and has a limited field of view. Here we report an alternative method that avoids these limitations and is easily implemented on an unmodified transmission electron microscope (TEM) operating in the familiar selected area diffraction mode. We use ptychography, an imaging technique popular amongst the X-ray microscopy community; recent advances in reconstruction algorithms now reveal its potential as a tool for highly sensitive, quantitative electron phase imaging.
Copy number variation in the region harboring SOX9 gene in dogs with testicular/ovotesticular disorder of sex development (78,XX; SRY-negative)
Authors: Marcinkowska-Swojak Malgorzata , Szczerbal Izabela , Pausch Hubert , Nowacka-Woszuk Joanna , Flisikowski Krzysztof , Dzimira Stanislaw , Nizanski Wojciech , Payan-Carreira Rita , Fries Ruedi , Kozlowski Piotr , Switonski Marek
Published: October 2015

Although the disorder of sex development in dogs with female karyotype (XX DSD) is quite common, its molecular basis is still unclear. Among mutations underlying XX DSD in mammals are duplication of a long sequence upstream of the SOX9 gene (RevSex) and duplication of the SOX9 gene (also observed in dogs). We performed a comparative analysis of 16 XX DSD and 30 control female dogs, using FISH and MLPA approaches. Our study was focused on a region harboring SOX9 and a region orthologous to the human RevSex (CanRevSex), which was located by in silico analysis downstream of SOX9. Two highly polymorphic copy number variable regions (CNVRs): CNVR1 upstream of SOX9 and CNVR2 encompassing CanRevSex were identified. Although none of the detected copy number variants were specific to either affected or control animals, we observed that the average number of copies in CNVR1 was higher in XX DSD. No copy variation of SOX9 was observed. Our extensive studies have excluded duplication of SOX9 as the common cause of XX DSD in analyzed samples. However, it remains possible that the causative mutation is hidden in highly polymorphic CNVR1.
MeSiC: A Model-Based Method for Estimating 5 mC Levels at Single-CpG Resolution from MeDIP-seq
Authors: Xiao Yun , Yu Fulong , Pang Lin , Zhao Hongying , Liu Ling , Zhang Guanxiong , Liu Tingting , Zhang Hongyi , Fan Huihui , Zhang Yan , Pang Bo , Li Xia
Published: October 2015

As the fifth base in mammalian genome, 5-methylcytosine (5 mC) is essential for many biological processes including normal development and disease. Methylated DNA immunoprecipitation sequencing (MeDIP-seq), which uses anti-5 mC antibodies to enrich for methylated fraction of the genome, is widely used to investigate methylome at a resolution of 100–500 bp. Considering the CpG density-dependent bias and limited resolution of MeDIP-seq, we developed a Random Forest Regression (RFR) model method, MeSiC, to estimate DNA methylation levels at single-base resolution. MeSiC integrated MeDIP-seq signals of CpG sites and their surrounding neighbors as well as genomic features to construct genomic element-dependent RFR models. In the H1 cell line, a high correlation was observed between MeSiC predictions and actual 5 mC levels. Meanwhile, MeSiC enabled to calibrate CpG density-dependent bias of MeDIP-seq signals. Importantly, we found that MeSiC models constructed in the H1 cell line could be used to accurately predict DNA methylation levels for other cell types. Comparisons with methylCRF and MEDIPS showed that MeSiC achieved comparable and even better performance. These demonstrate that MeSiC can provide accurate estimations of 5 mC levels at single-CpG resolution using MeDIP-seq data alone.
An automated fitting procedure and software for dose-response curves with multiphasic features
Authors: Di Veroli Giovanni Y. , Fornari Chiara , Goldlust Ian , Mills Graham , Koh Siang Boon , Bramhall Jo L , Richards Frances M. , Jodrell Duncan I.
Published: October 2015

In cancer pharmacology (and many other areas), most dose-response curves are satisfactorily described by a classical Hill equation (i.e. 4 parameters logistical). Nevertheless, there are instances where the marked presence of more than one point of inflection, or the presence of combined agonist and antagonist effects, prevents straight-forward modelling of the data via a standard Hill equation. Here we propose a modified model and automated fitting procedure to describe dose-response curves with multiphasic features. The resulting general model enables interpreting each phase of the dose-response as an independent dose-dependent process. We developed an algorithm which automatically generates and ranks dose-response models with varying degrees of multiphasic features. The algorithm was implemented in new freely available Dr Fit software (sourceforge.net/projects/drfit/). We show how our approach is successful in describing dose-response curves with multiphasic features. Additionally, we analysed a large cancer cell viability screen involving 11650 dose-response curves. Based on our algorithm, we found that 28% of cases were better described by a multiphasic model than by the Hill model. We thus provide a robust approach to fit dose-response curves with various degrees of complexity, which, together with the provided software implementation, should enable a wide audience to easily process their own data.
Synergistic algicidal effect and mechanism of two diketopiperazines produced by Chryseobacterium sp. strain GLY-1106 on the harmful bloom-forming Microcystis aeruginosa
Authors: Guo Xingliang , Liu Xianglong , Pan Jianliang , Yang Hong
Published: October 2015

A potent algicidal bacterium isolated from Lake Taihu, Chryseobacterium sp. strain GLY-1106, produces two algicidal compounds: 1106-A (cyclo(4-OH-Pro-Leu)) and 1106-B (cyclo(Pro-Leu)). Both diketopiperazines showed strong algicidal activities against Microcystis aeruginosa, the dominant bloom-forming cyanobacterium in Lake Taihu. Interestingly, these two algicidal compounds functioned synergistically. Compared with individual treatment, combined treatment with cyclo(4-OH-Pro-Leu) and cyclo(Pro-Leu) significantly enhanced algicidal activity, accelerated the increase in intracellular reactive oxygen species (ROS) levels in M. aeruginosa and further decreased the activities of antioxidases, effective quantum yield and maximal electron transport rate of M. aeruginosa. The results also showed that the algicidal characteristics of cyclo(4-OH-Pro-Leu) are distinct from those of cyclo(Pro-Leu). Cyclo(4-OH-Pro-Leu) mainly interrupted the flux of electron transport in the cyanobacterial photosynthetic system, whereas cyclo(Pro-Leu) mainly inhibited the activity of cyanobacterial intracellular antioxidases. A possible algicidal mechanism for the synergism between cyclo(4-OH-Pro-Leu) and cyclo(Pro-Leu) is proposed, which is in accordance with their distinct algicidal characteristics in individual and combined treatment. These findings suggest that synergism between algicidal compounds might be used as an effective strategy for the future control of Microcystis blooms.
Activation of the AMPK-ULK1 pathway plays an important role in autophagy during prion infection
Authors: Fan Xue-Yu , Tian Chan , Wang Hui , Xu Yin , Ren Ke , Zhang Bao-Yun , Gao Chen , Shi Qi , Meng Ge , Zhang Lu-Bin , Zhao Yang-Jing , Shao Qi-Xiang , Dong Xiao-Ping
Published: October 2015

AMPK is a serine/threonine protein kinase that acts as a positive regulator of autophagy, by phosphorylating ULK1 at specific sites. A previous study demonstrated activation of the macroautophagic system in scrapie-infected experimental rodents and in certain human prion diseases, in which the essential negative regulator mTOR is severely inhibited. In this study, AMPK and ULK1 in the brains of hamsters infected with scrapie strain 263 K and in the scrapie-infected cell line SMB-S15 were analysed. The results showed an up-regulated trend of AMPK and AMPK-Thr172, ULK1 and ULK1-Ser555. Increases in brain AMPK and ULK1 occurred at an early stage of agent 263 K infection. The level of phosphorylated ULK1-Ser757 decreased during mid-infection and was only negligibly present at the terminal stage, a pattern that suggested a close relationship of the phosphorylated protein with altered endogenous mTOR. In addition, the level of LKB1 associated with AMPK activation was selectively increased at the early and middle stages of infection. Knockdown of endogenous ULK1 in SMB-S15 cells inhibited LC3 lipidation. These results showed that, in addition to the abolishment of the mTOR regulatory pathway, activation of the AMPK-ULK1 pathway during prion infection contributes to autophagy activation in prion-infected brain tissues.
Piezoresistive effects in controllable defective HFTCVD graphene-based flexible pressure sensor
Authors: Mohammad Haniff Muhammad Aniq Shazni , Muhammad Hafiz Syed , Wahid Khairul Anuar Abd , Endut Zulkarnain , Wah Lee Hing , Bien Daniel C. S. , Abdul Azid Ishak , Abdullah Mohd. Zulkifly , Ming Huang Nay , Abdul Rahman Saadah
Published: October 2015

In this work, the piezoresistive effects of defective graphene used on a flexible pressure sensor are demonstrated. The graphene used was deposited at substrate temperatures of 750, 850 and 1000 °C using the hot-filament thermal chemical vapor deposition method in which the resultant graphene had different defect densities. Incorporation of the graphene as the sensing materials in sensor device showed that a linear variation in the resistance change with the applied gas pressure was obtained in the range of 0 to 50 kPa. The deposition temperature of the graphene deposited on copper foil using this technique was shown to be capable of tuning the sensitivity of the flexible graphene-based pressure sensor. We found that the sensor performance is strongly dominated by the defect density in the graphene, where graphene with the highest defect density deposited at 750 °C exhibited an almost four-fold sensitivity as compared to that deposited at 1000 °C. This effect is believed to have been contributed by the scattering of charge carriers in the graphene networks through various forms such as from the defects in the graphene lattice itself, tunneling between graphene islands and tunneling between defect-like structures.
Optimizing plasmonic nanoantennas via coordinated multiple coupling
Authors: Lin Linhan , Zheng Yuebing
Published: October 2015

Plasmonic nanoantennas, which can efficiently convert light from free space into sub-wavelength scale with the local field enhancement, are fundamental building blocks for nanophotonic systems. Predominant design methods, which exploit a single type of near- or far-field coupling in pairs or arrays of plasmonic nanostructures, have limited the tunability of spectral response and the local field enhancement. To overcome this limit, we are developing a general strategy towards exploiting the coordinated effects of multiple coupling. Using Au bowtie nanoantenna arrays with metal-insulator-metal configuration as examples, we numerically demonstrate that coordinated design and implementation of various optical coupling effects leads to both the increased tunability in the spectral response and the significantly enhanced electromagnetic field. Furthermore, we design and analyze a refractive index sensor with an ultra-high figure-of-merit (254), a high signal-to-noise ratio and a wide working range of refractive indices and a narrow-band near-infrared plasmonic absorber with 100% absorption efficiency, high quality factor of up to 114 and a wide range of tunable wavelength from 800 nm to 1,500 nm. The plasmonic nanoantennas that exploit coordinated multiple coupling will benefit a broad range of applications, including label-free bio-chemical detection, reflective filter, optical trapping, hot-electron generation and heat-assisted magnetic recording.
The lethal response to Cdk1 inhibition depends on sister chromatid alignment errors generated by KIF4 and isoform 1 of PRC1
Authors: Voets Erik , Marsman Judith , Demmers Jeroen , Beijersbergen Roderick , Wolthuis Rob
Published: October 2015

Cyclin-dependent kinase 1 (Cdk1) is absolutely essential for cell division. Complete ablation of Cdk1 precludes the entry of G2 phase cells into mitosis and is early embryonic lethal in mice. Dampening Cdk1 activation, by reducing gene expression or upon treatment with cell-permeable Cdk1 inhibitors, is also detrimental for proliferating cells, but has been associated with defects in mitotic progression and the formation of aneuploid daughter cells. Here, we used a large-scale RNAi screen to identify the human genes that critically determine the cellular toxicity of Cdk1 inhibition. We show that Cdk1 inhibition leads to fatal sister chromatid alignment errors and mitotic arrest in the spindle checkpoint. These problems start early in mitosis and are alleviated by depletion of isoform 1 of PRC1 (PRC1-1), by gene ablation of its binding partner KIF4, or by abrogation of KIF4 motor activity. Our results show that, normally, Cdk1 activity must rise above the level required for mitotic entry. This prevents KIF4-dependent PRC1-1 translocation to astral microtubule tips and safeguards proper chromosome congression. We conclude that cell death in response to Cdk1 inhibitors directly relates to chromosome alignment defects generated by insufficient repression of PRC1-1 and KIF4 during prometaphase.
Volatile fragrances associated with flowers mediate host plant alternation of a polyphagous mirid bug
Authors: Pan Hongsheng , Lu Yanhui , Xiu Chunli , Geng Huihui , Cai Xiaoming , Sun Xiaoling , Zhang Yongjun , Williams III Livy , Wyckhuys Kris A. G. , Wu Kongming
Published: October 2015

Apolygus lucorum(Hemiptera: Miridae) is an important insect pest of cotton and fruit trees in China. The adults prefer host plants at the flowering stage and their populations track flowering plants both spatially and temporally. In this study, we examine whether flower preference of its adults is mediated by plant volatiles and which volatile compositions play an important role in attracting them. In olfactometer tests with 18 key host species, the adults preferred flowering plants over non-flowering plants of each species. Coupled gas chromatography-electroantennography revealed the presence of seven electrophysiologically active compounds from flowering plants. Although the adults responded to all seven synthetic plant volatiles in electroantennography tests, only four (m-xylene, butyl acrylate, butyl propionate and butyl butyrate) elicited positive behavioral responses in Y-tube olfactometer bioassays. The adults were strongly attracted to these four active volatiles in multi-year laboratory and field trials. Our results suggest that these four fragrant volatiles, which are emitted in greater amounts once plants begin to flower, mediateA. lucorum’s preference to flowering host plants. We proved that the use of commonly occurring plant volatiles to recognize a large range of plant species can facilitate host selection and preference of polyphagous insect herbivore.
Square wave adsorptive stripping voltammetric determination of anticancer drug nilutamide in biological fluids using cationic surfactant cetyltrimethylammonium bromide
Authors: Temerk Yassien , Ibrahim Hossieny , Farhan Nasser
Published: October 2015

A sensitive square wave adsorptive stripping voltammetric method was described for the determination of anticancer drug nilutamide in human biological fluids based on the enhancement effect of the cationic surfactant: cetyltrimethylammonium bromide (CTAB).
Nucleus-staining with biomolecule-mimicking nitrogen-doped carbon dots prepared by a fast neutralization heat strategy
Authors: Kang Yan-Fei , Fang Yang-Wu , Li Yu-Hao , Li Wen , Yin Xue-Bo
Published: September 2015

Biomolecule-mimicking nitrogen-doped carbon dots were synthesized from dopamine for nucleus-staining by a neutralization heat strategy.
Direct observation of DME carbonylation in the different channels of H-MOR zeolite by continuous-flow solid-state NMR spectroscopy
Authors: He Ting , Ren Pengju , Liu Xianchun , Xu Shutao , Han Xiuwen , Bao Xinhe
Published: October 2015

Surface acetyl intermediates on HMOR zeolites (CH3CO-Z) were detected during DME carbonylation using in situ continuous-flow 13C MAS NMR spectroscopy.
Cu-catalyzed transannulation reaction of pyridotriazoles: general access to fused polycyclic indolizines
Authors: Shi Yi , Gevorgyan Vladimir
Published: October 2015

An efficient intramolecular transannulation reaction of pyridotriazoles using internal alkynes en route to various fused polycyclic indolizines has been developed. For the first time it is shown that in addition to the well-established Rh- or Cu-catalyzed carbene mechanism, the transannulation reaction could also follow a Lewis acid-mediated electrophilic pathway.
Exfoliating biocompatible ferromagnetic Cr-trihalide monolayers
Authors: Liu Junyi , Sun Qiang , Kawazoe Yoshiyuki , Jena Puru
Published: September 2015

Cr-trihalide monolayers CrX3 (X = Cl, Br, I) can be exfoliated from their layered bulk phase, exhibiting high in-plane stiffness, tunable Curie temperatures and biocompatibility.
Zirconium complexes stabilized by amine-bridged bis(phenolato) ligands as precatalysts for intermolecular hydroamination reactions
Authors: Sun Qiu , Wang Yaorong , Yuan Dan , Yao Yingming , Shen Qi
Published: October 2015

Pentacoordinate zirconium complexes 5 and 7 stabilized by amine-bridged bis(phenolato) ligands are more active than hexacoordinate complexes 1–4 in catalyzing intermolecular hydroamination reactions.
Stability and toxicity of tris-tolyl bismuth(v) dicarboxylates and their biological activity towards Leishmania major
Authors: Ong Yih Ching , Blair Victoria L. , Kedzierski Lukasz , Tuck Kellie L. , Andrews Philip C.
Published: October 2015

A series of tris-tolylbismuth(v) dicarboxylates, [Bi(Tol)3(O2CR)2], were synthesised, characterised and evaluated againstLeishmania majorparasites demonstrating good selectivity towards promastigotes but with more moderate success against amastigotes.
Monitoring guanine photo-oxidation by enantiomerically resolved Ru(ii) dipyridophenazine complexes using inosine-substituted oligonucleotides
Authors: Keane Páraic M. , Poynton Fergus E. , Hall James P. , Clark Ian P. , Sazanovich Igor V. , Towrie Michael , Gunnlaugsson Thorfinnur , Quinn Susan J. , Cardin Christine J. , Kelly John M.
Published: October 2015

The intercalating [Ru(TAP)2(dppz)]2+complex can photo-oxidise guanine in DNA, although in mixed-sequence DNA it can be difficult to understand the precise mechanism due to uncertainties in where and how the complex is bound. Replacement of guanine with the less oxidisable inosine (I) base can be used to understand the mechanism of electron transfer (ET). Here the ET has been compared for both Λ- and Δ-enantiomers of [Ru(TAP)2(dppz)]2+in a set of sequences where guanines in the readily oxidisable GG step in {TCGGCGCCGA}2have been replaced with I. The ET has been monitored using picosecond and nanosecond transient absorption and picosecond time-resolved IR spectroscopy. In both cases inosine replacement leads to a diminished yield, but the trends are strikingly different for Λ- and Δ-complexes.
Designing disordered materials using DNA-coated colloids of bacteriophage fd and gold
Authors: Ruff Z. , Nathan S. H. , Unwin R. R. , Zupkauskas M. , Joshi D. , Salmond G. P. C. , Grey C. P. , Eiser E.
Published: October 2015

DNA has emerged as an exciting binding agent for programmable colloidal self-assembly. Its popularity derives from its unique properties: it provides highly specific short-ranged interactions and at the same time it acts as a steric stabilizer against non-specific van der Waals and Coulomb interactions. Because complementary DNA strands are linked only via hydrogen bonds, DNA-mediated binding is thermally reversible: it provides an effective attraction that can be switched off by raising the temperature only by a few degrees. In this article we introduce a new binary system made of DNA-functionalized filamentous fd viruses of ∼880 nm length with an aspect ratio of ∼100, and 50 nm gold nanoparticles (gold NPs) coated with the complementary DNA strands. When quenching mixtures below the melt temperature Tm, at which the attraction is switched on, we observe aggregation. Conversely, above Tm the system melts into a homogenous particulate ‘gas’. We present the aggregation behavior of three different gold NP to virus ratios and compare them to a gel made solely of gold NPs. In particular, we have investigated the aggregate structures as a function of cooling rate and determine how they evolve as function of time for given quench depths, employing fluorescence microscopy. Structural information was extracted in the form of an effective structure factor and chord length distributions. Rapid cooling rates lead to open aggregates, while slower controlled cooling rates closer to equilibrium DNA hybridization lead to more fine-stranded gels. Despite the different structures we find that for both cooling rates the quench into the two-phase region leads to initial spinodal decomposition, which becomes arrested. Surprisingly, although the fine-stranded gel is disordered, the overall structure and the corresponding length scale distributions in the system are remarkably reproducible. Such highly porous systems can be developed into new functional materials.
Potentiation of Francisella resistance to conventional antibiotics through small molecule adjuvants
Authors: Stephens Matthew D. , Hubble Veroncia B. , Ernst Robert K. , van Hoek Monique L. , Melander Roberta J. , Cavanagh John , Melander Christian
Published: September 2015

A screen of 20 compounds identified small molecule adjuvants capable of potentiating antibiotic activity against Francisella philomiragia.
Multi-drug delivery nanocarriers for combination therapy
Authors: Gadde Suresh
Published: October 2015

The main focus of this review is to discuss recent advances in nanoparticle-based multi-drug delivery platforms towards combination therapy.
A study of the electrochemical behavior at low temperature of the Li3V2(PO4)3 cathode material for Li-ion batteries
Authors: Tai Ling-Hua , Zhao Qin , Sun Li-Qun , Cong Li-Na , Wu Xing-Long , Zhang Jing-Ping , Wang Rong-Shun , Xie Hai-Ming , Chen Xiao-Hong
Published: September 2015

CNT coatings combined with an optimized electrolyte are introduced to improve the low temperature performances of Li3V2(PO4)3.
Fluorescent nanoparticles based on AIE fluorogens for bioimaging
Authors: Yan Lulin , Zhang Yan , Xu Bin , Tian Wenjing
Published: October 2015

The latest advances in the development of fluorescent nanoparticles (FNPs) based on AIE fluorogens for bioimaging were summarized.
Efficient ternary organic photovoltaics incorporating a graphene-based porphyrin molecule as a universal electron cascade material
Authors: Stylianakis M. M. , Konios D. , Kakavelakis G. , Charalambidis G. , Stratakis E. , Coutsolelos A. G. , Kymakis E. , Anastasiadis S. H.
Published: September 2015

Graphene-based porphyrin molecule (GO-TPP), was used in high efficient ternary blend organic photovoltaics, demonstrating its universal role as electron cascade material.
A smart magnetic nanoplatform for synergistic anticancer therapy: manoeuvring mussel-inspired functional magnetic nanoparticles for pH responsive anticancer drug delivery and hyperthermia
Authors: Sasikala Arathyram Ramachandra Kurup , GhavamiNejad Amin , Unnithan Afeesh Rajan , Thomas Reju George , Moon Myeongju , Jeong Yong Yeon , Park Chan Hee , Kim Cheol Sang
Published: September 2015

The synergistic anticancer mechanism exhibited by smart HEDO–Fe3O4 nanoparticles by combining pH responsive anticancer drug delivery with hyperthermia.
Triphenylamine-decorated BODIPY fluorescent probe for trace detection of picric acid
Authors: Hengchang Ma , Zhongwei Zhang , Yuanyuan Jin , Lajia Zha , Chunxuan Qi , Haiying Cao , Zengming Yang , Zhiwang Yang , Ziqiang Lei
Published: September 2015

The near-IR photoactive material TBMA demonstrated high selectivity and sensitivity for picric acid detection with low detection limit and high quenching constant.
Synthesis of Zn3V2O8 nanoplatelets for lithium-ion battery and supercapacitor applications
Authors: Vijayakumar Subbukalai , Lee Seong-Hun , Ryu Kwang-Sun
Published: September 2015

The Zn3V2O8 nanoplatelets exhibit a maximum specific capacitance of 302 F g−1 with 98% capacitance retention.
A facile citric acid assisted sol–gel method for preparing monolithic yttria-stabilized zirconia aerogel
Authors: Zhang Zhiyi , Gao Qiuyue , Liu Yi , Zhou Chunmei , Zhi Mingjia , Hong Zhanglian , Zhang Fan , Liu Bin
Published: September 2015

Citric acid was used as the cheap and environmental friendly gelation accelerator for preparation of monolithic zirconia aerogel.
Memory effect in weakly-interacting Fe3O4 nanoparticles
Authors: Gandhi Ashish Chhaganal , Reddy P. Muralidhar , Chan Ting-Shan , Ho Yen-Peng , Wu Sheng Yun
Published: September 2015

The observed field cooling memory effect of Fe3O4 nanoparticles is induced by the interparticle interactions.
Effects of niobium and molybdenum impregnation on adsorption capacity and Fenton catalytic activity of magnetite
Authors: Rahim Pouran Shima , Abdul Aziz A. R. , Wan Daud Wan Mohd Ashri , Shafeeyan Mohammad Saleh
Published: September 2015

Nb and Mo co-incorporation could effectively improve magnetite properties towards higher adsorption and remarkable activity in heterogeneous Fenton process.
ACdCO3F (A = K and Rb): new noncentrosymmetric materials with remarkably strong second-harmonic generation (SHG) responses enhanced via π-interaction
Authors: Zou Guohong , Nam Gnu , Kim Hyung Gu , Jo Hongil , You Tae-Soo , Ok Kang Min
Published: September 2015

The remarkably large SHG efficiency of KCdCO3F originates from enhancement via interatomic interactions between the s and p states of Cd2+ and the π-conjugated groups of the [CO3]2− unit.
Facile synthesis of ordered mesoporous Ni–Zr–Al catalysts with high hydrothermal stability for CO methanation
Authors: Liu Qing , Gu Fangna , Wang Xiaoyan , Jin Guojing , Li Huifang , Gao Feng , Zhong Ziyi , Xu Guangwen , Su Fabing
Published: September 2015

The ordered mesoporous Ni–Zr–Al catalyst exhibits high hydrothermal stability as well as high anti-coking and anti-sintering properties, due to the confinement effect of the mesopore channels and the incorporation of the ZrO2 species.
Powder activated carbon/Fe3O4 hybrid composite as a highly efficient heterogeneous catalyst for Fenton oxidation of tetracycline: degradation mechanism and kinetic
Authors: Jaafarzadeh Nemat , Kakavandi Babak , Takdastan Afshin , Kalantary Roshanak Rezaei , Azizi Minoo , Jorfi Sahand
Published: September 2015

In this work, we prepared and used a composite of powder activate carbon/Fe3O4 magnetic nanoparticles (PAC/Fe3O4 MNPs) as a heterogeneous catalyst to remove tetracycline (TC) from aqueous solution.
Substitution effect on the photochromic properties of benzo[b]thiophene-1,1-dioxide based diarylethenes
Authors: Chen Shangjun , Li Wenlong , Li Xin , Zhu Wei-Hong
Published: September 2015

Benzo[b]thiophene-1,1-dioxide based diarylethenes containing methyl, phenyl, formyl and triphenylamine groups are developed for taking insight into substituent effects on the absorption properties and photochromism.
Metal chalcogenides as counter electrode materials in quantum dot sensitized solar cells: a perspective
Authors: Meng Ke , Chen Gang , Thampi K. Ravindranathan
Published: September 2015

This article reviews the application of metal chalcogenide counter electrodes in quantum dot sensitized solar cells.
High proton conductivity in cyanide-bridged metal–organic frameworks: understanding the role of water
Authors: Gao Yuan , Broersen Richard , Hageman Wouter , Yan Ning , Mittelmeijer-Hazeleger Marjo C. , Rothenberg Gadi , Tanase Stefania
Published: October 2015

Hop hop hop: the proton conductivity of the [Nd(mpca)2Nd(H2O)6Mo(CN)8]·nH2O is enabled by lattice water molecules in its channels.
Highly efficient polyoxometalate-based catalysts for clean-gasoline synthesis
Authors: Wang Chunling , Liu Cheng , Hu Yunhang , Bu Xianni , Zhao Tiejun , Chou Kuochih , Li Qian
Published: September 2015

The introduction of CsPW into Co/Al2O3 leads to 118% increase in the selectivity of gasoline.
“Sea cucumber”-like Ti@MoO3 nanorod arrays as self-supported lithium ion battery anodes with enhanced rate capability and durability
Authors: Zhao Guangyu , Li Changle , Zhang Li , Lv Jixian , Niu Yanning , Du Ying , Sun Kening
Published: October 2015

“Sea cucumber”-like Ti@MoO3 nanorod arrays show enhanced rate capability and excellent durability as self-supported lithium ion battery anodes.
Self-assembled novel dandelion-like NiCo2O4 microspheres@nanomeshes with superior electrochemical performance for supercapacitors and lithium-ion batteries
Authors: Liu Li , Zhang Huijuan , Yang Jiao , Mu Yanping , Wang Yu
Published: September 2015

Herein, novel dandelion-like NiCo2O4 microspheres@nanomeshes have been successfully fabricated and displayed superior electrochemical performances for SCs and LIBs.
Highly pseudocapacitive Nb-doped TiO2 high power anodes for lithium-ion batteries
Authors: Lübke Mechthild , Shin Juhun , Marchand Peter , Brett Dan , Shearing Paul , Liu Zhaolin , Darr Jawwad A.
Published: October 2015

Nb-doped and pure TiO2 (anatase) nanoparticles were synthesized via a continuous hydrothermal flow synthesis reactor and investigated as electrode material for lithium-ion batteries.
Pore size regulates mesenchymal stem cell response to Bioglass-loaded composite scaffolds
Authors: Vissers Caroline A. B. , Harvestine Jenna N. , Leach J. Kent
Published: September 2015

Composite scaffolds fabricated from synthetic polymers and bioceramics such as bioactive glasses are promising alternatives to autogenous bone grafts for treatment of bone defects.
Surface roughness boosts the SERS performance of imprinted plasmonic architectures
Authors: Macias Gerard , Alba María , Marsal Lluís F. , Mihi Agustín
Published: October 2015

Rough 2D plasmonic crystals pose as inexpensive and easily processed SERS substrates exhibiting enhancement factors up to 1.6 × 1010.
Sublethal vancomycin-induced ROS mediating antibiotic resistance in Staphylococcus aureus
Authors: Li Gui-qiu , Quan Feng , Qu Ting , Lu Juan , Chen Shu-lan , Cui Lan-ying , Guo Da-wen , Wang Yong-chen
Published: October 2015

Staphylococcus aureus is the leading cause of many human infectious diseases. Besides infectious dangers, S. aureus is well-known for the quickly developed drug resistance. Although great efforts have been made, mechanisms underlying the antibiotic effects of S. aureus are still not well clarified. Recently, reports have shown that oxidative stress connects with bactericidal antibiotics [Dwyer et al. (2009) Curr. Opin. Microbiol. 12, 482–489]. Based on this point, we demonstrate that reactive oxygen species (ROS) induced by sublethal vancomycin may be partly responsible for the antibiotic resistance in heterogeneous vancomycin resistant S. aureus (hVRSA). Sublethal vancomycin treatment may induce protective ROS productions in hVRSA, whereas reduction in ROS level in hVRSA strains may increase their vancomycin susceptibility. Moreover, low dose of ROS in VSSA (vancomycin susceptible S. aureus) strains may promote their survival under vancomycin conditions. Our findings reveal that modest ROS generation may be protective for vancomycin resistance in hVRSA. These results recover novel insights into the relationship between oxidative stress and bacterial resistance, which has important applications for further use of antibiotics and development of therapeutics strategies for hVRSA.
Chronic aerobic swimming exercise promotes functional and morphological changes in rat ileum
Authors: da Cunha Araujo Layanne Cabral , de Souza Iara Leão Luna , Vasconcelos Luiz Henrique César , de Freitas Brito Aline , Queiroga Fernando Ramos , Silva Alexandre Sérgio , da Silva Patrícia Mirella , de Andrade Cavalcante Fabiana , da Silva Bagnólia Araújo
Published: October 2015

Several studies have reported the gastrointestinal (GI) effects promoted by the physical exercise. Thus, we aimed to evaluate the influence of swimming exercise on the contractile reactivity, lipid peroxidation and morphology of rat ileum. Wistar rats were divided into sedentary (SED) and groups exercised for two (EX2), four (EX4), six (EX6) or eight (EX8) weeks, 5 days/week. Animals were killed; the ileum was removed and suspended in organ baths where the isotonic contractions were recorded. Lipid peroxidation was evaluated by MDA (malondialdehyde) measurement with TBARS (thiobarbituric acid reactive substances) assay and morphology by histological staining. Cumulative concentration-response curves to KCl were attenuated, as the Emax values were changed from 100% (SED) to 63.1±3.9 (EX2), 48.8±3.8 (EX4), 19.4±1.8 (EX6) and 59.4±2.8% (EX8). Similarly, cumulative concentration-response curves to carbamylcholine hydrochloride (CCh) were attenuated, as the Emax values were changed from 100% (SED) to 74.1±5.4 (EX2), 75.9±5.2 (EX4) and 62.9±4.6 (EX6), but not in the EX8 (89.7±3.4%). However, CCh potency was increased in this latter, as the EC50 was altered from 1.0±0.1×10−6 (SED) to 2.1±0.4×10−7 (EX8). MDA concentration was altered only in EX4 (44.3±4.4) compared with SED (20.6±3.6 μmol/l). Circular layer was reduced in SED when compared with the exercised groups. Conversely, longitudinal layer was increased. In conclusion, chronic swimming exercise reduces the ileum contraction, equilibrates the oxidative damage and promotes changes in tissue size to establish an adaptation to the exercise.
Exploring Expressive Vocabulary Variability in Two-Year-Olds: The Role of Working Memory
Authors: Newbury Jayne , Klee Thomas , Stokes Stephanie F. , Moran Catherine
Published: October 2015

Purpose

This study explored whether measures of working memory ability contribute to the wide variation in 2-year-olds' expressive vocabulary skills.

Method

Seventy-nine children (aged 24–30 months) were assessed by using standardized tests of vocabulary and visual cognition, a processing speed measure, and behavioral measures of verbal working memory and phonological short-term memory.

Results

Strong correlations were observed between phonological short-term memory, verbal working memory, and expressive vocabulary. Speed of spoken word recognition showed a moderate significant correlation with expressive vocabulary. In a multivariate regression model for expressive vocabulary, the most powerful predictor was a measure of phonological short-term memory (accounting for 66% unique variance), followed by verbal working memory (6%), sex (2%), and age (1%). Processing speed did not add significant unique variance.

Conclusions

These findings confirm previous research positing a strong role for phonological short-term memory in early expressive vocabulary acquisition. They also extend previous research in two ways. First, a unique association between verbal working memory and expressive vocabulary in 2-year-olds was observed. Second, processing speed was not a unique predictor of variance in expressive vocabulary when included alongside measures of working memory.
Bayesian algorithm for high‐resolution DOA estimation
Authors: Zhang Yin , Huang Yulin , Yang Jianyu
Published: October 2015

A maximum a posteriori (MAP) algorithm based on Bayesian criterion for high‐resolution direction‐of‐arrival (DOA) estimation in array signal processing is proposed. The generalised Gaussian distribution was considered as the prior information of sources distribution for its wide applicability. The statistic parameter of the generalised Gaussian function can be transformed according to different sources distribution conditions. Only the sparse signal recovery problem is considered. It is found that with the generalised Gaussian sparse constraint, the proposed MAP algorithm provides high DOA estimation performance in the case of limited snapshots. Simulation results are given to verify the effectiveness and efficiency of the proposed algorithm.
Perceptual rate distortion optimisation for video coding using free‐energy principle
Authors: Jung Cheolkon , Chen Yao
Published: October 2015

In this Letter, a novel perceptual rate distortion optimisation (RDO) method based on the free‐energy principle is proposed. The human visual system is not sensitive to the distortion hidden in disorderly regions due to the disorderly concealment effect, i.e. the free‐energy principle. Based on the human visual perception, we introduce a free‐energy based just‐notable‐difference (FEJND) model into the RDO process to adaptively adjust the Lagrange multiplier and quantisation parameter values. Experimental results show that the proposed method conceals more distortions in disorderly regions and achieves 8.46% bit‐rate reduction over the JM reference software at the same perceptual quality level.
Precoding for secrecy rate maximisation in cognitive MIMO wiretap channels
Authors: Fang Bing , Qian Zuping , Zhong Wei , Shao Wei
Published: October 2015

The problem of physical layer security in a cognitive MIMO wiretap channel is studied. The problem is formulated as a secrecy rate maximisation (SRM) problem, and solved by a successive convex approximation (SCA) method. With the SCA method, the non‐convex part of the SRM problem is approximated by its first‐order Taylor expansion. Then, relying on solving a series of convexified optimisation problems, an iterative precoding algorithm is developed.
Reverse‐curve‐arch‐shaped dry EEG electrode for increased skin–electrode contact area on hairy scalps
Authors: Lee Jeong Su , Han Chung Min , Kim Jee Hoon , Park Kwang Suk
Published: October 2015

Electroencephalography (EEG) is electrical brain activity that can be measured on the scalp with Ag/AgCl electrodes and conductive gel. However, time‐consuming preparation procedures, dehydration of the gel, and skin irritation are crucial drawbacks of using such electrodes. Alternative approaches involving the use of spiky dry electrodes have their own drawbacks such as limited skin–electrode contact area, high skin–electrode impedance, and pain. Reverse‐curve‐arch‐shaped dry EEG electrodes for use in increasing the skin–electrode contact area on hairy scalps are presented. The proposed electrode was fabricated from sterling silver using a three‐dimensional printer. To increase the contact area between the skin and an electrode, an electrode was designed to have reverse‐curve arches which were arranged in a row on the electrode base. The curvature of the arches was designed to match the curvature of the scalp to maximise the contact area and disperse the pressing force. To validate the proposed electrode design, comparison experiments for EEG and skin–electrode contact impedance were conducted, and the proposed electrode was found to perform better than a commercially available finger‐type dry electrode.
Symmetry‐analysis‐based diagnosis method with correlation coefficients for open‐circuit fault in inverter
Authors: Wu Feng , Zhao Jin , Liu Yang
Published: October 2015

A current‐based, real‐time and fast symmetry‐analysis‐based diagnosis method with a correlation coefficient for an open‐circuit fault in a voltage‐source inverter is proposed. The proposed method includes three steps: data reconstruction, features extraction, fault detection and isolation. To achieve fair robustness, real‐time and fast performance, sliding windows with length of a period current samples are designed for data reconstruction. Correlation coefficients of each of the two phase currents are designed to describe the symmetry of the inverter both in a healthy and a faulty condition, and mean values of current samples during a period are used to accurately isolate the faulty switch or switches. The proposed method is current‐based sharing the current sensors that are used for the current regulators, hence it is low‐cost. The high effectiveness and merit of the proposed method are validated by experiments.
Area‐detection fibre‐optic system for spatially offset Raman spectroscopy and Raman tomography in reflection mode
Authors: Wang Zhiyong , Yang Hao , Ding Hao , Lu Guijin , Jiang Huabei , Bi Xiaohong
Published: October 2015

A new design of a fibre‐optic probe system is presented which can be used to simultaneously detect scattering signals from multiple channels for spatially offset Raman spectroscopy and Raman tomography in reflection mode. The fibre setup contained 32 source fibres with an auto‐controlled optical switch and 40 detector fibres, which were deployed in a large‐area planar interface. Phantom experiments were conducted using a prototype of the Raman instrument, and have demonstrated the practical applicability of the system design. The presented area‐detection instrument provides an efficient platform for various reflectance applications of Raman modalities over a large area. It could also be potentially adopted for other diffuse optical‐based spectroscopic and tomographic applications.
Fractional Fourier transform‐based unassisted tracking method for Global Navigation Satellite System signal carrier with high dynamics
Authors: Xia Xuan , Zhao Jiankang , Long Haihui , Yang Guang , Sun Jun , Yang Wenbo
Published: October 2015

This study proposes a novel tracking method for Global Navigation Satellite System (GNSS) signal carrier, based on fractional Fourier transform. This method not only overcomes the limitations caused by the tripartite trade‐off between tracking accuracy, loop bandwidth and dynamic stress, but also needs no auxiliary devices such as inertial measurement units (IMUs). Through a time–frequency analysis of high dynamic carrier signal, the authors show that an acceleration estimator can replace the function of IMU, and a high dynamic frequency discriminator can track the carrier Doppler frequency. Since the tracking accuracy (frequency resolution) and loop bandwidth (time resolution) are not affected by dynamics in the authors’ method, the upper bound of dynamic stress is improved significantly. Furthermore, due to the cancellation of IMU calibration and initial alignment, their method improves the rapid reaction capability of vehicles, reduces the possibility of external interference, and simplifies the tracking loop design. Simulation results show that their method has the ability to track GNSS signal under at least 200 g dynamic stress.
Characterization of carrier transport properties in strained crystalline Si wall-like structures in the quasi-quantum regime
Authors: Mayberry C. S. , Huang Danhong , Balakrishnan G. , Kouhestani C. , Islam N. , Brueck S. R. J. , Sharma A. K.
Published: October 2015

We report the transport characteristics of both electrons and holes through narrow constricted crystalline Si “wall-like” long-channels that were surrounded by a thermally grown SiO2 layer. The strained buffering depth inside the Si region (due to Si/SiO2 interfacial lattice mismatch) is where scattering is seen to enhance some modes of the carrier-lattice interaction, while suppressing others, thereby changing the relative value of the effective masses of both electrons and holes, as compared to bulk Si. In the narrowest wall devices, a considerable increase in conductivity was observed as a result of higher carrier mobilities due to lateral constriction and strain. The strain effects, which include the reversal splitting of light- and heavy-hole bands as well as the decrease of conduction-band effective mass by reduced Si bandgap energy, are formulated in our microscopic model for explaining the experimentally observed enhancements in both conduction- and valence-band mobilities with reduced Si wall thickness. Also, the enhancements of the valence-band and conduction-band mobilities are found to be associated with different aspects of theoretical model.
Higher-order diagrammatic vibrational coupled-cluster theory
Authors: Faucheaux Jacob A. , Hirata So
Published: October 2015

Diagrammatically size-consistent and basis-set-free vibrational coupled-cluster (XVCC) theory for both zero-point energies and transition frequencies of a molecule, the latter through the equation-of-motion (EOM) formalism, is defined for an nth-order Taylor-series potential energy surface (PES). Quantum-field-theoretical tools (the rules of normal-ordered second quantization and Feynman–Goldstone diagrams) for deriving their working equations are established. The equations of XVCC and EOM-XVCC including up to the mth-order excitation operators are derived and implemented with the aid of computer algebra in the range of 1 ≤ m ≤ 8. Algorithm optimizations known as strength reduction, intermediate reuse, and factorization are carried out before code generation, reducing the cost scaling of the mth-order XVCC and EOM-XVCC in an nth-order Taylor-series PES (m ≥ n) to the optimal value of O(Nm+⌊n/2⌋), where N is the number of modes. The calculated zero-point energies and frequencies of fundamentals, overtones, and combinations as well as Fermi-resonant modes display rapid and nearly monotonic convergence with m towards the exact values for the PES. The theory with the same excitation rank as the truncation order of the Taylor-series PES (m = n) seems to strike the best cost-accuracy balance, achieving the accuracy of a few tenths of cm−1 for transitions involving (m − 3) modes and of a few cm−1 for those involving (m − 2) modes. The relationships between XVCC and the vibrational coupled-cluster theories of Prasad and coworkers and of Christiansen and coworkers as well as the size-extensive vibrational self-consistent-field and many-body perturbation theories are also elucidated.
Networkcontrology
Authors: Motter Adilson E.
Published: October 2015

An increasing number of complex systems are now modeled as networks of coupled dynamical entities. Nonlinearity and high-dimensionality are hallmarks of the dynamics of such networks but have generally been regarded as obstacles to control. Here, I discuss recent advances on mathematical and computational approaches to control high-dimensional nonlinear network dynamics under general constraints on the admissible interventions. I also discuss the potential of network control to address pressing scientific problems in various disciplines.