bluuebunny/crossref_metadata_2025 huggingface dataset:
Naturally occurring hybrids derived from γ-amino acids and sugars with potential tail to tail ether-bonds
Authors: Feng Zi-ming , Zhan Zhi-lai , Yang Ya-nan , Jiang Jian-shuang , Zhang Pei-cheng
Published: May 2016

The basic substances of life include various amino acids and sugars. To search such molecules is the precondition to understand the essential nature. Here we reported four unprecedented hybrids of γ-amino acids and sugars from the roots of Ranunculus ternatus, which possess potential tail to tail ether-connected (6,6-ether-connected) modes in the sugar moiety. The structures of these hybrids were elucidated by extensive analyses of spectra and calculated electronic circular dichroism (ECD) method.
Acute blockade of IL-25 in a colitis associated colon cancer model leads to increased tumor burden
Authors: Thelen Tennille D. , Green Ryan M. , Ziegler Steven F.
Published: May 2016

Chronic inflammation within the gastrointestinal tract results in an increased risk for developing colorectal cancer. Epithelial cytokines, including interleukin-25 (IL-25), are produced in the colon and are critical for protection from parasites, but can also be pathogenic in the context of inflammatory bowel diseases and allergy. Whether IL-25 is involved in the progression from inflammation to cancer is still largely unexplored. Using a well-established murine model for colitis-induced colon cancer; we aimed to determine the role of IL-25 in this process. We found that acute IL-25 blockade resulted in greater tumor burdens compared to isotype control treated mice. Histologically, α-IL-25 treated mice had increased colitis scores compared to mice receiving isotype control antibody, as well as decreased eosinophilia. This is the first study to explore the therapeutic potential of using an IL-25 blocking antibody during a chronic inflammatory setting. Taken together these data suggest that IL-25 plays an inhibitory role in the growth and development of colonic tumors.
Surface stress of graphene layers supported on soft substrate
Authors: Du Feng , Huang Jianyong , Duan Huiling , Xiong Chunyang , Wang Jianxiang
Published: May 2016

We obtain the surface stress of a single layer and multilayers of graphene supported on silicone substrates by measuring the deformation of the graphene-covered substrates induced by the surface tension of liquid droplets together with the Neumann’s triangle concept. We find that the surface stress of the graphene-covered substrate is significant larger than that of the bare substrate and it increases with increasing graphene layers and finally reaches a constant value of about 120 mN/m on three and more layers of graphene. This work demonstrates that the apparent surface stress of graphene-substrate systems can be tuned by the substrate and the graphene layers. The surface stress and the tuning effect of the substrate on it may have applications in design and characterization of graphene-based ultra-sensitive sensors and other devices. Moreover, the method may also be used to measure the surface stress of other ultrathin films supported on soft substrates.
Opposite transcriptional regulation of integrated vs unintegrated HIV genomes by the NF-κB pathway
Authors: Thierry Sylvain , Thierry Eloïse , Subra Frédéric , Deprez Eric , Leh Hervé , Bury-Moné Stéphanie , Delelis Olivier
Published: May 2016

Integration of HIV-1 linear DNA into host chromatin is required for high levels of viral expression, and constitutes a key therapeutic target. Unintegrated viral DNA (uDNA) can support only limited transcription but may contribute to viral propagation, persistence and/or treatment escape under specific situations. The molecular mechanisms involved in the differential expression of HIV uDNA vs integrated genome (iDNA) remain to be elucidated. Here, we demonstrate, for the first time, that the expression of HIV uDNA is mainly supported by 1-LTR circles, and regulated in the opposite way, relatively to iDNA, following NF-κB pathway modulation. Upon treatment activating the NF-κB pathway, NF-κB p65 and AP-1 (cFos/cJun) binding to HIV LTR iDNA correlates with increased iDNA expression, while uDNA expression decreases. On the contrary, inhibition of the NF-κB pathway promotes the expression of circular uDNA, and correlates with Bcl-3 and AP-1 binding to its LTR region. Finally, this study identifies NF-κB subunits and Bcl-3 as transcription factors binding the HIV promoter differently depending on viral genome topology, and opens new insights on the potential roles of episomal genomes during the HIV-1 latency and persistence.
Minicollagen cysteine-rich domains encode distinct modes of polymerization to form stable nematocyst capsules
Authors: Tursch Anja , Mercadante Davide , Tennigkeit Jutta , Gräter Frauke , Özbek Suat
Published: May 2016

The stinging capsules of cnidarians, nematocysts, function as harpoon-like organelles with unusual biomechanical properties. The nanosecond discharge of the nematocyst requires a dense protein network of the capsule structure withstanding an internal pressure of up to 150 bar. Main components of the capsule are short collagens, so-called minicollagens, that form extended polymers by disulfide reshuffling of their cysteine-rich domains (CRDs). Although CRDs have identical cysteine patterns, they exhibit different structures and disulfide connectivity at minicollagen N and C-termini. We show that the structurally divergent CRDs have different cross-linking potentials in vitro and in vivo. While the C-CRD can participate in several simultaneous intermolecular disulfides and functions as a cystine knot after minicollagen synthesis, the N-CRD is monovalent. Our combined experimental and computational analyses reveal the cysteines in the C-CRD fold to exhibit a higher structural propensity for disulfide bonding and a faster kinetics of polymerization. During nematocyst maturation, the highly reactive C-CRD is instrumental in efficient cross-linking of minicollagens to form pressure resistant capsules. The higher ratio of C-CRD folding types evidenced in the medusozoan lineage might have fostered the evolution of novel, predatory nematocyst types in cnidarians with a free-swimming medusa stage.
Cloud-based Electronic Health Records for Real-time, Region-specific Influenza Surveillance
Authors: Santillana M. , Nguyen A. T. , Louie T. , Zink A. , Gray J. , Sung I. , Brownstein J. S.
Published: May 2016

Accurate real-time monitoring systems of influenza outbreaks help public health officials make informed decisions that may help save lives. We show that information extracted from cloud-based electronic health records databases, in combination with machine learning techniques and historical epidemiological information, have the potential to accurately and reliably provide near real-time regional estimates of flu outbreaks in the United States.
Highly Robust Neutral Plane Oxide TFTs Withstanding 0.25 mm Bending Radius for Stretchable Electronics
Authors: Kim Yong-Hwan , Lee Eunji , Um Jae Gwang , Mativenga Mallory , Jang Jin
Published: May 2016

Advancements in thin-film transistor (TFT) technology have extended to electronics that can withstand extreme bending or even folding. Although the use of ultrathin plastic substrates has achieved considerable advancement towards this end, free-standing ultrathin plastics inevitably suffer from mechanical instability and are very difficult to handle during TFT fabrication. Here, in addition to the use of a 1.5 μm-thick polyimide (PI) substrate, a 1.5 μm-thick PI film is also deposited on top of the TFT devices to ensure that the devices are located at the neutral plane of the two PI films for high folding stability. For mechanical support during TFT fabrication up to the deposition of the top PI film, the PI substrate is spin coated on top of a carrier glass that is coated with a mixture of carbon nanotubes (CNTs) and graphene oxide (GO). The mixture of CNT and GO facilitates mechanical detachment of the neutral plane (NP) TFTs from the carrier glass before they are transferred to a polydimethylsiloxane (PDMS) substrate as islands. Being located in the neutral bending plane, the NP TFT can be transferred to the PDMS without performance degradation and exhibit excellent mechanical stability after stretching the PDMS substrate up to a 25% elastic elongation.
miARma-Seq: a comprehensive tool for miRNA, mRNA and circRNA analysis
Authors: Andrés-León Eduardo , Núñez-Torres Rocío , Rojas Ana M.
Published: May 2016

Large-scale RNAseq has substantially changed the transcriptomics field, as it enables an unprecedented amount of high resolution data to be acquired. However, the analysis of these data still poses a challenge to the research community. Many tools have been developed to overcome this problem, and to facilitate the study of miRNA expression profiles and those of their target genes. While a few of these enable both kinds of analysis to be performed, they also present certain limitations in terms of their requirements and/or the restrictions on data uploading. To avoid these restraints, we have developed a suite that offers the identification of miRNA, mRNA and circRNAs that can be applied to any sequenced organism. Additionally, it enables differential expression, miRNA-mRNA target prediction and/or functional analysis. The miARma-Seq pipeline is presented as a stand-alone tool that is both easy to install and flexible in terms of its use, and that brings together well-established software in a single bundle. Our suite can analyze a large number of samples due to its multithread design. By testing miARma-Seq in validated datasets, we demonstrate here the benefits that can be gained from this tool by making it readily accessible to the research community.
Aquaporin-3 potentiates allergic airway inflammation in ovalbumin-induced murine asthma
Authors: Ikezoe Kohei , Oga Toru , Honda Tetsuya , Hara-Chikuma Mariko , Ma Xiaojun , Tsuruyama Tatsuaki , Uno Kazuko , Fuchikami Jun-ichi , Tanizawa Kiminobu , Handa Tomohiro , Taguchi Yoshio , Verkman Alan S. , Narumiya Shuh , Mishima Michiaki , Chin Kazuo
Published: May 2016

Oxidative stress plays a pivotal role in the pathogenesis of asthma. Aquaporin-3 (AQP3) is a small transmembrane water/glycerol channel that may facilitate the membrane uptake of hydrogen peroxide (H2O2). Here we report that AQP3 potentiates ovalbumin (OVA)-induced murine asthma by mediating both chemokine production from alveolar macrophages and T cell trafficking. AQP3 deficient (AQP3−/−) mice exhibited significantly reduced airway inflammation compared to wild-type mice. Adoptive transfer experiments showed reduced airway eosinophilic inflammation in mice receiving OVA-sensitized splenocytes from AQP3−/− mice compared with wild-type mice after OVA challenge, consistently with fewer CD4+ T cells from AQP3−/− mice migrating to the lung than from wild-type mice. Additionally, in vivo and vitro experiments indicated that AQP3 induced the production of some chemokines such as CCL24 and CCL22 through regulating the amount of cellular H2O2 in M2 polarized alveolar macrophages. These results imply a critical role of AQP3 in asthma and AQP3 may be a novel therapeutic target.
Word pair classification during imagined speech using direct brain recordings
Authors: Martin Stephanie , Brunner Peter , Iturrate Iñaki , Millán José del R. , Schalk Gerwin , Knight Robert T. , Pasley Brian N.
Published: May 2016

People that cannot communicate due to neurological disorders would benefit from an internal speech decoder. Here, we showed the ability to classify individual words during imagined speech from electrocorticographic signals. In a word imagery task, we used high gamma (70–150 Hz) time features with a support vector machine model to classify individual words from a pair of words. To account for temporal irregularities during speech production, we introduced a non-linear time alignment into the SVM kernel. Classification accuracy reached 88% in a two-class classification framework (50% chance level), and average classification accuracy across fifteen word-pairs was significant across five subjects (mean = 58%; p < 0.05). We also compared classification accuracy between imagined speech, overt speech and listening. As predicted, higher classification accuracy was obtained in the listening and overt speech conditions (mean = 89% and 86%, respectively; p < 0.0001), where speech stimuli were directly presented. The results provide evidence for a neural representation for imagined words in the temporal lobe, frontal lobe and sensorimotor cortex, consistent with previous findings in speech perception and production. These data represent a proof of concept study for basic decoding of speech imagery, and delineate a number of key challenges to usage of speech imagery neural representations for clinical applications.
Comprehensive evaluation of candidate reference genes for qRT-PCR studies of gene expression in mustard aphid, Lipaphis erysimi (Kalt)
Authors: Koramutla Murali Krishna , Aminedi Raghavendra , Bhattacharya Ramcharan
Published: May 2016

Mustard aphid, also known as turnip aphid (Lipaphis erysimi) is a major insect pest of rapeseed-mustard group of crops. Tremendous economic significance has led to substantial basic research involving gene-expression studies in this insect species. In qRT-PCR analysis of gene-expression, normalization of data against RNA variation by using appropriate reference gene is fundamental. However, appropriate reference genes are not known in case of L. erysimi. We evaluated 11 candidate reference genes for their expression stability in 21 samples of L. erysimi subjected to various regimes of experimental treatments. Unlike other studies, we validated true effects of the treatments on the samples either by gene-expression study of an associated marker gene or by biochemical tests. In the validated samples, expression stability of the reference genes was analysed by employing four different statistical softwares geNorm, NormFinder, BestKeeper and deltaCt. Drawing consensus on the results from different softwares, we recommend three best reference genes 16S, RPS18 and RPL13 for normalization of qRT-PCR data in L. erysimi. This study provides for the first time a comprehensive list of suitable reference genes for mustard aphid and demonstrates the advantage of using more than one reference gene in combination for certain experimental conditions.
Control factors and scale analysis of annual river water, sediments and carbon transport in China
Authors: Song Chunlin , Wang Genxu , Sun Xiangyang , Chang Ruiying , Mao Tianxu
Published: May 2016

Under the context of dramatic human disturbances on river system, the processes that control the transport of water, sediment, and carbon from river basins to coastal seas are not completely understood. Here we performed a quantitative synthesis for 121 sites across China to find control factors of annual river exports (Rc: runoff coefficient; TSSC: total suspended sediment concentration; TSSL: total suspended sediment loads; TOCL: total organic carbon loads) at different spatial scales. The results indicated that human activities such as dam construction and vegetation restoration might have a greater influence than climate on the transport of river sediment and carbon, although climate was a major driver of Rc. Multiple spatial scale analyses indicated that Rc increased from the small to medium scale by 20% and then decreased at the sizable scale by 20%. TSSC decreased from the small to sizeable scale but increase from the sizeable to large scales; however, TSSL significantly decreased from small (768 g·m−2·a−1) to medium spatial scale basins (258 g·m−2·a−1), and TOCL decreased from the medium to large scale. Our results will improve the understanding of water, sediment and carbon transport processes and contribute better water and land resources management strategies from different spatial scales.
A DFT study of 2-aminopurine-containing dinucleotides: prediction of stacked conformations with B-DNA structure
Authors: Smith Darren A. , Holroyd Leo F. , van Mourik Tanja , Jones Anita C.
Published: May 2016

DFT calculations predict base-stacked and base-flipped structures of 2-aminopurine-containing DNA dinucleotides.
Nanoporous iron(iii) porphyrin frameworks: an efficient catalyst for [4+2] cycloaddition reactions of unactivated aldehydes with a diene
Authors: Singh Manoj Kumar , Bandyopadhyay Debkumar
Published: May 2016

The one pot conversion of several unactivated aldehydes with a diene to their corresponding [4+2] cycloaddition products has been studied using nanoporous iron(iii) porphyrin frameworks as catalysts.
A fluorometric assay platform for caffeic acid detection based on the G-quadruplex/hemin DNAzyme
Authors: Cai Nan , Li Yan , Chen Shufan , Su Xingguang
Published: May 2016

A fluorometric assay platform based on GQDs is designed for biochemical detection of caffeic acid.
An array of individually addressable micro-needles for mapping pH distributions
Authors: Zuliani Claudio , Ng Fu Siong , Alenda Andrea , Eftekhar Amir , Peters Nicholas S. , Toumazou Christofer
Published: May 2016

This work describes the preparation of an array of individually addressable pH sensitive microneedles which demonstrated suitable for measuring pH distribution during heart ischemia and reperfusion cycles.
Study on the effect of spectral difference coefficient on the precision of quantitative spectral analysis
Authors: Liu Hongyan , Wang Mengjun , LI Xiaoxia , Li Zhe , Li Gang , Lin Ling
Published: May 2016

The influence mechanism of interferents on the quantitative spectral analysis of an analyte in a multicomponent mixture has been explored.
Combining the uniform design-based ray procedure with combination index to investigate synergistic lethal toxicities of ternary mixtures on Caenorhabditis elegans
Authors: Tang Han-Xiao , Liu Shu-Shen , Li Kai , Feng Li
Published: May 2016

A method combining the uniform design-based ray procedure and combination index integrated with observation-based confidence intervals is proposed to assess the combined toxicities of ternary mixtures on C. elegans.
Structural- and optical-properties analysis of single crystalline hematite (α-Fe2O3) nanocubes prepared by one-pot hydrothermal approach
Authors: Abdul Rashid Nur Maisarah , Haw Choonyian , Chiu Weesiong , Khanis Noor Hamizah , Rohaizad Aliff , Khiew PoiSim , Abdul Rahman Saadah
Published: May 2016

Time-dependent morphological evolution analysis shows high quality crystalline α-Fe2O3 nanocubes can be precisely tuned and synthesized by a facile, green, yet straightforward strategy via a hydrothermal method.
Cocrystals of the antiandrogenic drug bicalutamide: screening, crystal structures, formation thermodynamics and lattice energies
Authors: Surov Artem O. , Solanko Katarzyna A. , Bond Andrew D. , Bauer-Brandl Annette , Perlovich German L.
Published: May 2016

Two new cocrystals of the antiandrogenic drug bicalutamide with benzamide and salicylamide are reported. Relationships between crystal structures, melting temperatures, aqueous dissolution, formation thermodynamics and crystal lattice energies of the cocrystals are investigated.
Diverse polyoxometalate-based metal–organic complexes constructed by a tetrazole- and pyridyl-containing asymmetric amide ligand or its in situ transformed ligand
Authors: Wang Xiu-Li , Rong Xing , Liu Dan-Na , Lin Hong-Yan , Liu Guo-Cheng , Wang Xiang , Song Ge
Published: May 2016

Four metal–organic complexes constructed from different polyoxoanions and a tetrazole- and pyridyl-containing asymmetric amide ligand or its in situ transformed ligand have been synthesized and structurally characterized.
Structural effect of glyme–Li+ salt solvate ionic liquids on the conformation of poly(ethylene oxide)
Authors: Chen Zhengfei , McDonald Samila , Fitzgerald Paul A. , Warr Gregory G. , Atkin Rob
Published: May 2016

Conformation of poly(ethylene oxide) in solvate ionic liquids is affected by the solvent structure.
Why is a proton transformed into a hydride by [NiFe] hydrogenases? An intrinsic reactivity analysis based on conceptual DFT
Authors: Qiu Siyao , Azofra Luis Miguel , MacFarlane Douglas R. , Sun Chenghua
Published: May 2016

The hydrogen evolution reaction (HER) catalysed by [NiFe] hydrogenases entails a series of chemical events involving great mechanistic interest.
Biomolecule-assisted synthesis of defect-mediated Cd1−xZnxS/MoS2/graphene hollow spheres for highly efficient hydrogen evolution
Authors: Du Ruifeng , Zhang Yihe , Li Baoying , Yu Xuelian , Liu Huijuan , An Xiaoqiang , Qu Jiuhui
Published: May 2016

The in situ formation of defect-rich MoS2 cocatalysts exhibited a significant impact on the photocatalytic activity of Cd1−xZnxS/MoS2/graphene hollow spheres.
Solvation structure around the Li+ ion in succinonitrile–lithium salt plastic crystalline electrolytes
Authors: Shen Yuneng , Deng Gang-Hua , Ge Chuanqi , Tian Yuhuan , Wu Guorong , Yang Xueming , Zheng Junrong , Yuan Kaijun
Published: May 2016

The FTIR spectra and rotation decay of pure SN and Li–SN complex in LiBF4/SN solutions.
Dispersible lanthanide organic hybrid nanoparticles: synthesis, morphology and application
Authors: Zhou Xia , Ling Jun , Sun Weilin , Shen Zhiquan
Published: May 2016

Novel nanoparticles of coordination polymers (CPs) with various morphologies are successfully prepared.
Synthesis and biodistribution of novel 99mTcN complexes of glucose dithiocarbamate as potential probes for tumor imaging
Authors: Liu Teli , Gan Qianqian , Zhang Junbo , Jin Zhonghui , Zhang Weifang , Zhang Yanyan
Published: May 2016

99mTcN-3b can be prepared from a kit without the need for purification and would be a promising tumor imaging agent.
Insights into solute carriers: physiological functions and implications in disease and pharmacokinetics
Authors: Estudante Margarida , Soveral Graça , Morais José G. , Benet Leslie Z.
Published: May 2016

SLCs transport many endogenous and exogenous compounds including drugs; SLCs dysfunction has implications in pharmacokinetics, drug toxicity or lack of efficacy.
Synthesis of the first POSS cage–anthracycline conjugates via amide bonds
Authors: Piorecka Kinga , Radzikowska Ewa , Kurjata Jan , Rozga-Wijas Krystyna , Stanczyk Wlodzimierz A. , Wielgus Ewelina
Published: May 2016

Synthetic routes leading to nanoconjugates of polyhedral silsesquioxane T8 with doxorubicin and daunorubicin have been developed.
Tetracoordinate Co(ii) complexes containing bathocuproine and single molecule magnetism
Authors: Smolko Lukáš , Černák Juraj , Dušek Michal , Titiš Ján , Boča Roman
Published: May 2016

Chlorido complex [Co(bcp)Cl2] exhibits a field-induced SMM behaviour, while in the bromide and iodido analogues only weak antiferromagnetic interactions are present.
Novel bioluminescent coelenterazine derivatives with imidazopyrazinone C-6 extended substitution for Renilla luciferase
Authors: Jiang Tianyu , Yang Xiaofeng , Yang Xingye , Yuan Mingliang , Zhang Tianchao , Zhang Huateng , Li Minyong
Published: May 2016

Novel coelenterazine analogues displayed excellent bioluminescence propertiesin cellulo, thus becoming favourable molecules for bioluminescence techniques.
On the fly multi-modal observation of ligand synthesis and complexation of Cu complexes in flow with ‘benchtop’ NMR and mass spectrometry
Authors: Porwol Luzian , Henson Alon , Kitson Philip J. , Long De-Liang , Cronin Leroy
Published: May 2016

The transfer of one-pot reactions to a continuous non-equilibrium set-up for real-time observation of the self-assembly of new coordination compounds is presented.
Therapeutic potential of a synthetic FABP4 inhibitor 8g on atherosclerosis in ApoE-deficient mice: the inhibition of lipid accumulation and inflammation
Authors: Pei Heying , Xie Caifeng , Liu Yibin , Shao Mingfeng , Chen Jinying , Li Dan , Ma Liang , Chen Lijuan
Published: May 2016

We discovered a synthetic FABP4 inhibitor that ameliorated the symptoms of atherosclerosis and suppressed lipid accumulation.
An enhanced oxygen electrode catalyst by incorporating CoO/SnO2 nanoparticles in crumpled nitrogen-doped graphene in alkaline media
Authors: Ma Xiu-Xiu , He Xing-Quan
Published: May 2016

An advanced and highly efficient oxygen electrode catalyst was fabricated by anchoring CoO/SnO2 nanocrystals on nitrogen-doped graphene.
Visible light-induced aerobic C–N bond activation: a photocatalytic strategy for the preparation of 2-arylpyridines and 2-arylquinolines
Authors: Hu Bei , Li Yuyuan , Dong Wuheng , Xie Xiaomin , Wan Jun , Zhang Zhaoguo
Published: May 2016

An efficient method for accessing arylpyridines and arylquinolines via visible light-induced aerobic C–N bond activation is described.
Optimization of ammonia nitrogen removal by SO42− intercalated hydrotalcite using response surface methodology
Authors: Duan Heng-Zhi , Zeng Hong-Yan , Xiao Hua-Miao , Chen Chao-Rong , Xiao Gao-Fei , Zhao Quan
Published: May 2016

SO42− intercalated Mg–Al hydrotalcite (S-LDH) was prepared under microwave irradiation and characterized by powder X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM).
α-Glucosidase inhibitory activities of phenolic acid amides with l-amino acid moiety
Authors: Liu Bin , Ma Ji-Mei , Chen Hang-Wei , Li Zi-Long , Sun Lin-Hao , Zeng Zhen , Jiang Hong
Published: May 2016

Phenolic acid amides with a l-amino acid moiety showed excellent inhibitory activity on α-glucosidase.
Gas–solid conversion of lignin to carboxylic acids
Authors: Lotfi Samira , Boffito Daria C. , Patience Gregory S.
Published: May 2016

We combine thermo-chemical processes with oxidative catalysis to convert lignin to aliphatic carboxylic acids mainly C4 acids. Acid selectivity changed with catalyst.
How cracks are hot and cool: a burning issue for paper
Authors: Toussaint Renaud , Lengliné Olivier , Santucci Stéphane , Vincent-Dospital Tom , Naert-Guillot Muriel , Måløy Knut Jørgen
Published: May 2016

Snapshot of the crack propagation, with a colored image of the IR camera superimposed with the corresponding optical image. The heated zone precedes an open crack. The black dots on the paper are patterns that were printed for deformation measurement and image analysis purposes.
Solubility of transition metal interstitials in proton conducting BaZrO3and similar perovskite oxides
Authors: Polfus Jonathan M. , Fontaine Marie-Laure , Thøgersen Annett , Riktor Marit , Norby Truls , Bredesen Rune
Published: May 2016

The defect chemistry of foreign transition metals in perovskite oxides was investigated by first-principles calculations in combination with experiments with focus on Ni and Zn in Y-doped BaZrO3.
A thermoresponsive fluorescent rotor based on a hinged naphthalimide for a viscometer and a viscosity-related thermometer
Authors: Xia Tengkun , Wang Linlin , Qu Yi , Rui Yichuan , Cao Jian , Hu Yue , Yang Ji , Wu Jianwei , Xu Jingli
Published: May 2016

A bisnaphthalimide-based fluorescent probe (BNAP) was synthesized for rapid detection of viscosity and viscosity-related temperature variations.
Catalpol inhibits apoptosis in hydrogen peroxide-induced cardiac myocytes through a mitochondrial-dependent caspase pathway
Authors: Hu Ling-ai , Sun Yu-kun , Zhang Hong-sheng , Zhang Jin-guo , Hu Jian
Published: May 2016

Catalpol, an iridoid glucoside, has been reported to inhibit apoptosis of neuron and endothelial cells. In the present study, we investigated the mechanism of catalpol-mediated cardioprotection. The rat embryonic ventricular myocardial cell line (H9c2) cells were first incubated with catalpol, and then exposed to hydrogen peroxide (H2O2). The concentration of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) were all determined by using commercially available kits. Apoptotic cells were assessed by Hoechst 33258 and Annexin V-fluorescein isothiocyanate binding assay. Synthesis of Bcl-2, Bax, cytochrome c and caspase-3 were analysed by real-time semiquantitative reverse transcription-PCR and Western blotting. We observed that apoptosis in H9c2 was associated with increased Bax, cytochrome c, caspase-3, decreased Bcl-2 activity after 24 h of H2O2 exposure. Catalpol pretreatment afforded a marked protection against the above H2O2-mediated cytotoxicity and apoptosis in H9c2 cells. Moreover, the catalpol pretreatment led to a great reduction in H2O2-induced MDA release and increased SOD. These findings indicated for the first time that pretreatment of H9c2 cells with catalpol can be against H2O2-induced apoptosis, and the protective effect of catalpol involves the mitochondrial-dependent caspase pathway and is associated with increased Bcl-2 and decreased Bax expression.
Image encryption by chaos mixing
Authors: Abanda Yannick , Tiedeu Alain
Published: May 2016

The need for image encryption is constantly on the rise and has led to the emergence of many techniques in literature. In recent years, many chaos‐based encryption techniques have developed with more or less success. In this study, we suggest one such approach using two oscillators. Mixed chaotic maps from the Colpitts and Duffing oscillators were used to encrypt images, which helped to increase the key space to 2448 ≃ 7.26 × 10134. The authors also succeeded to reduce the encryption time by saving the mixed chaotic maps and reusing them as need arose. The proposed system was tested on well‐known images like Lena, NebulaM83, Mandrill and Clown.
Unified model of boost converter in continuous and discontinuous conduction modes
Authors: Han Junfeng , Zhang Bo , Qiu Dongyuan
Published: May 2016

Much effort has been made to build appropriate models for a boost converter. However, these models were described as inexact or complicated expressions in both continuous conduction mode (CCM) and discontinuous conduction mode (DCM). This study proposes a new modelling method based on propositional calculus and linear constraint. First, the equivalent operating conditions (OCs) of the boost converter in CCM and DCM are formulated. Second, according to the equivalent translation principle, the OCs of the boost converter in three different modes can be transformed into two linear inequalities. Moreover then, a unified model of the boost converter in CCM and DCM is obtained. Compared with mixed logical dynamical model, the proposed model (PM) of the boost converter is more concise. In addition, the PM is a large‐signal model in the theoretical analysis. Finally, the model is simulated in MATLAB under different load conditions and its effectiveness is well verified by simulation results. Moreover, the experimental results are consistent with the simulation results.
Coupled sequential detection and estimation procedure for track‐before‐detect
Authors: Cui Guolong , Kong Lingjiang , Yi Wei , Wang Bailu , Yang Xiaobo
Published: May 2016

In this study, the authors consider the coupled sequential detection and estimation of weak targets for track‐before‐detect algorithm in long range early warning radar. They present a new strategy and develop a coupled cost function consisting of detection, position estimation and tracking estimation loss. In the proposed procedure, the sequential stopping and detection rules are simplified. Moreover, they derive the lower bounds of the detection and estimation probabilities, which can be used to design the suitable related parameter values. Finally, several numerical simulations of the new strategy and the comparisons are presented and discussed.
Graphene‐based THz modulator analysed by equivalent circuit model
Authors: Xiao Binggang , Chen Jing , Xie Zhiyi , Xiao Sanshui
Published: May 2016

A terahertz (THz) modulator based on graphene is proposed and analysed by use of equivalent transmission line of a homogeneous medium and the local anisotropic model of the graphene conductivity. The result calculated by the equivalent circuit is consistent with that obtained by Fresnel transfer matrices. For the modulator proposed here, when the frequency of carrier wave is 0.6 THz, the theoretical analysis indicates that the modulation bandwidth is 55.5 kHz and the modulation depth is 81.3% for voltage change from 0 to 50 V.
Assessment of the Learning Curve for Microendoscopic Decompression Surgery for Lumbar Spinal Canal Stenosis through an Analysis of 480 Cases Involving a Single Surgeon
Authors: Nomura Kazunori , Yoshida Munehito
Published: May 2016

Study Design

 Retrospective study.

Objective

 To assess the learning curve of microendoscopic decompression surgery for lumbar spinal canal stenosis (LSCS).

Methods

 Four hundred eighty LSCS cases involving 753 stenotic lesions limited to the intraspinal canal were treated with microendoscopic decompression by a single surgeon at an institution between November 2006 and January 2015. They were numbered chronologically, and the operating time, intraoperative blood loss, and perioperative complications were investigated. Surgical outcomes were evaluated using the Japanese Orthopedic Association (JOA) score for low back pain before and 1 year after the operation.

Results

 The mean operating time per level was 66.1 minutes. There was a progressive reduction in the operating time through the case series, and the approximate curve seemed to be y =  − 9.4Ln( x) + 115.0. The blood loss per level, which showed a mean value of 15.0 mL, was more than 50 mL in only 2.7% of the cases after case no. 30 and in 20% of the cases before it. There were 10 (2.1%) cases of perioperative complications, which occurred even after the surgeon had gained mastery of the procedure. The median JOA score improved significantly from 17 points preoperatively to 26 points postoperatively.

Conclusions

 The learning curve of microendoscopic decompression surgery for LSCS has been defined with data for a single surgeon in an institution. The operating time seems to decrease along a natural logarithmic function. The intraoperative blood loss stabilizes after the first 30 cases, whereas perioperative complications can occur at any time even after mastery of the technique.
The maximally entangled set of 4-qubit states
Authors: Spee C. , de Vicente J. I. , Kraus B.
Published: May 2016

Entanglement is a resource to overcome the natural restriction of operations used for state manipulation to Local Operations assisted by Classical Communication (LOCC). Hence, a bipartite maximally entangled state is a state which can be transformed deterministically into any other state via LOCC. In the multipartite setting no such state exists. There, rather a whole set, the Maximally Entangled Set of states (MES), which we recently introduced, is required. This set has on the one hand the property that any state outside of this set can be obtained via LOCC from one of the states within the set and on the other hand, no state in the set can be obtained from any other state via LOCC. Recently, we studied LOCC transformations among pure multipartite states and derived the MES for three and generic four qubit states. Here, we consider the non-generic four qubit states and analyze their properties regarding local transformations. As already the most coarse grained classification, due to Stochastic LOCC (SLOCC), of four qubit states is much richer than in case of three qubits, the investigation of possible LOCC transformations is correspondingly more difficult. We prove that most SLOCC classes show a similar behavior as the generic states, however we also identify here three classes with very distinct properties. The first consists of the GHZ and W class, where any state can be transformed into some other state non-trivially. In particular, there exists no isolation. On the other hand, there also exist classes where all states are isolated. Last but not least we identify an additional class of states, whose transformation properties differ drastically from all the other classes. Although the possibility of transforming states into local-unitary inequivalent states by LOCC turns out to be very rare, we identify those states (with exception of the latter class) which are in the MES and those, which can be obtained (transformed) non-trivially from (into) other states respectively. These investigations do not only identify the most relevant classes of states for LOCC entanglement manipulation, but also reveal new insight into the similarities and differences between separable and LOCC transformations and enable the investigation of LOCC transformations among arbitrary four qubit states.
Dissociative adsorption of H2O on LiCoO2 (00l) surfaces: Co reduction induced by electron transfer from intrinsic defects
Authors: Cherkashinin G. , Jaegermann W.
Published: May 2016

Understanding the mechanism of the interaction of lithium ion conductors with water is crucial for both fundamental and technological points of view. Despite the generally accepted fact that water is one of main sources of the degradation of Li-ion recharge batteries, the physicochemical processes occurring at the water-lithium ion conductor interface are not fully understood. By using synchrotron X-ray photoelectron spectroscopy (SXPS) and O K- and Co L- X-ray absorption near edge structure (XANES), we evidence that H2O is dissociatively adsorbed on LiCoO2 thin film at room temperature resulting in the formation of OH groups and the accumulation of the negative charge at the surface accompanied by electron transfer to the initial empty Co3d (eg*) state. By considering the experimentally obtained energy diagram of the ionic conductor and water, direct charge transfer is not favorable due to a high difference in the chemical potential of the ionic conductor and electronic levels of the molecule. Here, we develop the model for the dissociative water adsorption which explains the electron transfer to LiCoO2 by using the atomistic approach. The model takes into account the intrinsic defects found on the surface (<2 nm depth) by using the depth resolved photoemission experiments and can be explored to other layered transition metal oxides to interpret the interaction of water with the surface of ionic conductors.
Note: The expansion of possibilities for plasma probe diagnostics
Authors: Masherov P. E. , Riaby V. A. , Abgaryan V. K.
Published: May 2016

The determination of ion mass for low-pressure Maxwellian plasmas has been proposed. It can be done using Langmuir probe measurements and the Bohm formula for the ion current density to a floating probe, due to this formula’s reliance on ion mass. This goal was achieved by accurate measurements of xenon plasma parameters in the inductive discharge at pressure p = 2 ⋅ 10−3 Torr using the Plasma Sensors VGPS-12 probe station with the cylindrical Langmuir probes. The analysis of measurement data showed that in these conditions, the Bohm effect was valid with engineering-level precision, resulting in the experimental Bohm coefficient CBCyl ≈ 1.13 for cylindrical probes.
High-density ferroelectric recording using a hard disk drive-type data storage system
Authors: Aoki Tomonori , Hiranaga Yoshiomi , Cho Yasuo
Published: May 2016

Ferroelectric probe data storage has been proposed as a novel data storage method in which bits are recorded based on the polarization directions of individual domains. These bits are subsequently read by scanning nonlinear dielectric microscopy. The domain walls of typical ferroelectric materials are quite thin: often only several times the lattice constant, which is advantageous for high-density data storage. In this work, high-density read/write (R/W) demonstrations were conducted using a hard disk drive-type test system, and the writing of bit arrays with a recording density of 3.4 Tbit/in.2 was achieved. Additionally, a series of writing and reading operations was successfully demonstrated at a density of 1 Tbit/in.2. Favorable characteristics of ferroelectric recording media for use with the proposed method are discussed in the latter part of this paper.
In situ photoacoustic characterization for porous silicon growing: Detection principles
Authors: Ramirez-Gutierrez C. F. , Castaño-Yepes J. D. , Rodriguez-García M. E.
Published: May 2016

There are a few methodologies for monitoring the in-situ formation of Porous Silicon (PS). One of the methodologies is photoacoustic. Previous works that reported the use of photoacoustic to study the PS formation do not provide the physical explanation of the origin of the signal. In this paper, a physical explanation of the origin of the photoacoustic signal during the PS etching is provided. The incident modulated radiation and changes in the reflectance are taken as thermal sources. In this paper, a useful methodology is proposed to determine the etching rate, porosity, and refractive index of a PS film by the determination of the sample thickness, using scanning electron microscopy images. This method was developed by carrying out two different experiments using the same anodization conditions. The first experiment consisted of growth of the samples with different etching times to prove the periodicity of the photoacoustic signal, while the second one considered the growth samples using three different wavelengths that are correlated with the period of the photoacoustic signal. The last experiment showed that the period of the photoacoustic signal is proportional to the laser wavelength.
AlInAsSb separate absorption, charge, and multiplication avalanche photodiodes
Authors: Ren Min , Maddox Scott J. , Woodson Madison E. , Chen Yaojia , Bank Seth R. , Campbell Joe C.
Published: May 2016

We report AlxIn1−xAsySb1−y separate absorption, charge, and multiplication avalanche photodiodes (APDs) that operate in the short-wavelength infrared spectrum. They exhibit excess noise factor less or equal to that of Si and the low dark currents typical of III-V compound APDs.
Surface spin-electron acoustic waves in magnetically ordered metals
Authors: Andreev Pavel A. , Kuz'menkov L. S.
Published: May 2016

Degenerate plasmas with motionless ions show existence of three surface waves: the Langmuir wave, the electromagnetic wave, and the zeroth sound. Applying the separated spin evolution quantum hydrodynamics to half-space plasma, we demonstrate the existence of the surface spin-electron acoustic wave (SSEAW). We study dispersion of the SSEAW. We show that there is hybridization between the surface Langmuir wave and the SSEAW at rather small spin polarization. In the hybridization area, the dispersion branches are located close to each other. In this area, there is a strong interaction between these waves leading to the energy exchange. Consequently, generating the Langmuir waves with the frequencies close to hybridization area we can generate the SSEAWs. Thus, we report a method of creation of the spin-electron acoustic waves.
Current gain above 10 in sub-10 nm base III-Nitride tunneling hot electron transistors with GaN/AlN emitter
Authors: Yang Zhichao , Zhang Yuewei , Krishnamoorthy Sriram , Nath Digbijoy N. , Khurgin Jacob B. , Rajan Siddharth
Published: May 2016

We report on a tunneling hot electron transistor amplifier with common-emitter current gain greater than 10 at a collector current density in excess of 40 kA/cm2. The use of a wide-bandgap GaN/AlN (111 nm/2.5 nm) emitter was found to greatly improve injection efficiency of the emitter and reduce cold electron leakage. With an ultra-thin (8 nm) base, 93% of the injected hot electrons were collected, enabling a common-emitter current gain up to 14.5. This work improves understanding of the quasi-ballistic hot electron transport and may impact the development of high speed devices based on unipolar hot electron transport.
Lattice modification in KTiOPO4 by hydrogen and helium sequentially implantation in submicrometer depth
Authors: Ma Changdong , Lu Fei , Xu Bo , Fan Ranran
Published: May 2016

We investigated lattice modification and its physical mechanism in H and He co-implanted, z-cut potassium titanyl phosphate (KTiOPO4). The samples were implanted with 110 keV H and 190 keV He, both to a fluence of 4 × 1016 cm−2, at room temperature. Rutherford backscattering/channeling, high-resolution x-ray diffraction, and transmission electron microscopy were used to examine the implantation-induced structural changes and strain. Experimental and simulated x-ray diffraction results show that the strain in the implanted KTiOPO4 crystal is caused by interstitial atoms. The strain and stress are anisotropic and depend on the crystal's orientation. Transmission electron microscopy studies indicate that ion implantation produces many dislocations in the as-implanted samples. Annealing can induce ion aggregation to form nanobubbles, but plastic deformation and ion out-diffusion prevent the KTiOPO4 surface from blistering.
Fabrication of photonic amorphous diamonds for terahertz-wave applications
Authors: Komiyama Yuichiro , Abe Hiroyuki , Kamimura Yasushi , Edagawa Keiichi
Published: May 2016

A recently proposed photonic bandgap material, named “photonic amorphous diamond” (PAD), was fabricated in a terahertz regime, and its terahertz-wave propagation properties were investigated. The PAD structure was fabricated from acrylic resin mixed with alumina powder, using laser lithographic, micro-additive manufacturing technique. After fabrication, the resulting structure was dewaxed and sintered. The formation of a photonic bandgap at around 0.45 THz was demonstrated by terahertz time-domain spectroscopy. Reflecting the disordered nature of the random network structure, diffusive terahertz-wave propagation was observed in the passbands; the scattering mean-free path decreased as the frequency approached the band edge. The mean-free paths evaluated at the band edges were close to the Ioffe-Regel threshold value for wave localization.
Disorder-induced enhancement of indirect absorption in a GeSn photodetector grown by molecular beam epitaxy
Authors: Li H. , Chang C. , Cheng H. H. , Sun G. , Soref R. A.
Published: May 2016

We report an investigation on the absorption mechanism of a GeSn photodetector with 2.4% Sn composition in the active region. Responsivity is measured and absorption coefficient is calculated. Square root of absorption coefficient linearly depends on photon energy indicating an indirect transition. However, the absorption coefficient is found to be at least one order of magnitude higher than that of most other indirect materials, suggesting that the indirect optical absorption transition cannot be assisted only by phonon. Our analysis of absorption measurements by other groups on the same material system showed the values of absorption coefficient on the same order of magnitude. Our study reveals that the strong enhancement of absorption for the indirect optical transition is the result of alloy disorder from the incorporation of the much larger Sn atoms into the Ge lattice that are randomly distributed.