bluuebunny/crossref_metadata_2025 huggingface dataset:
Second harmonic generation in the bulk of silicon induced by an electric field of a high power terahertz pulse
Authors: Ovchinnikov A. V. , Chefonov O. V. , Mishina E. D. , Agranat M. B.
Published: July 2019

The experimental findings on the second harmonic generation (SHG) in centrosymmetric crystal silicon are reported. The SHG is induced by extremely high electric field (up to 15 MV/cm) parallel to the crystal surface of a short terahertz (THz) pulse while probing by an infrared femtosecond optical pulse. The SHG under such unique conditions is reported for the first time. At the electric field amplitude above 8 MV/cm, the quadratic dependence of the SHG yield integrated over the THz pulse duration on the electric field is violated and SHG yield is not changed with a further increase of the THz field. Saturation of SHG intensity at high electric fields is explained in terms of carrier density increase due to impact ionization and destructive interference of electric-field induced and current induced nonlinear polarizations.
Confocal photoluminescence investigation to identify basal stacking fault’s role in the optical properties of semi-polar InGaN/GaN lighting emitting diodes
Authors: Zhang Y. , Smith R. M. , Jiu L. , Bai J. , Wang T.
Published: July 2019

High spatial-resolution confocal photoluminescence (PL) measurements have been performed on a series of semi-polar (11–22) InGaN light emitting diodes (LEDs) with emission wavelengths up to yellow. These LED samples have been grown on our high crystal quality semi-polar GaN templates which feature periodically distributed basal stacking faults (BSFs), which facilitates the study of the influence of BSFs on their optical performance. Scanning confocal PL measurements have been performed across BSFs regions and BSF-free regions. For the blue LED, both the emission intensity and the emission wavelength exhibit a periodic behavior, matching the periodic distribution of BSFs. Furthermore, the BSF regions show a longer emission wavelength and a reduced emission intensity compared with the BSF-free regions. However, with increasing indium content, this periodic behavior in both emission intensity and emission wavelength becomes weaker and weaker. When the indium content (and correspondingly, wavelength) increases up to achieve yellow emission, only random fluctuations have been observed. It is worth highlighting that the influence of BSFs on the optical properties of semi-polar InGaN LEDs is different from the role of dislocations which normally act as non-radiative recombination centers.
Testes and duct deferens of mice during space flight: cytoskeleton structure, sperm-specific proteins and epigenetic events
Authors: Ogneva Irina V. , Usik Maria A. , Loktev Sergey S. , Zhdankina Yuliya S. , Biryukov Nikolay S. , Orlov Oleg I. , Sychev Vladimir N.
Published: July 2019

To analyze the effect of gravity on the structure of germinal tissues, we examined tissues of the testes and duct deferens of mice that were exposed to space flight conditions for 21–24 days (experiment Rodent Research-4, SpaceX-10 mission, February 2017, USA). We evaluated the levels of cytoskeletal proteins, sperm-specific proteins, and epigenetic events; in particular, we evaluated levels of 5-hydroxymethylcytosine and of enzymes that regulate DNA methylation/demethylation. We did not detect changes in the levels of cytoskeletal proteins, sperm-specific proteins, DNA-methylases, DNA demethylases, DNA acetylases, or histone deacetylases. However, there were changes at the gene expression level. In particular, there was an increase in the demethylase Tet2 and a decrease in the histone deacetylase Hdac1. These gene expression changes may be of key importance during the early period of readaptation since they could lead to an increase in the expression of target genes.
Pre-existing H4K16ac levels in euchromatin drive DNA repair by homologous recombination in S-phase
Authors: Horikoshi Nobuo , Sharma Dharmendra , Leonard Fransisca , Pandita Raj K. , Charaka Vijaya K. , Hambarde Shashank , Horikoshi Nobuko T. , Gaur Khaitan Puja , Chakraborty Sharmistha , Cote Jacques , Godin Biana , Hunt Clayton R. , Pandita Tej K.
Published: July 2019

The homologous recombination (HR) repair pathway maintains genetic integrity after DNA double-strand break (DSB) damage and is particularly crucial for maintaining fidelity of expressed genes. Histone H4 acetylation on lysine 16 (H4K16ac) is associated with transcription, but how pre-existing H4K16ac directly affects DSB repair is not known. To answer this question, we used CRISPR/Cas9 technology to introduce I-SceI sites, or repair pathway reporter cassettes, at defined locations within gene-rich (high H4K16ac/euchromatin) and gene-poor (low H4K16ac/heterochromatin) regions. The frequency of DSB repair by HR is higher in gene-rich regions. Interestingly, artificially targeting H4K16ac at specific locations using gRNA/dCas9-MOF increases HR frequency in euchromatin. Finally, inhibition/depletion of RNA polymerase II or Cockayne syndrome B protein leads to decreased recruitment of HR factors at DSBs. These results indicate that the pre-existing H4K16ac status at specific locations directly influences the repair of local DNA breaks, favoring HR in part through the transcription machinery.
Association of dietary fiber intake with hyperuricemia in U.S. adults
Authors: Sun Yongye , Sun Jianping , Zhang Peipei , Zhong Feng , Cai Jing , Ma Aiguo
Published: July 2019

Current evidence on the relationship between dietary fiber intake and risk of hyperuricemia is limited.
Donkey milk oligosaccharides influence the growth-related characteristics of intestinal cells and induce G2/M growth arrest via the p38 pathway in HT-29 cells
Authors: Wang Jingxuan , Lei Beibei , Yan Jingyu , Li Jiaqi , Zhou Xiangshan , Ren Fazheng , Guo Huiyuan
Published: July 2019

The growth inhibition pathway of DMOs in HT-29 cells.
Preparation, film fabrication and gas-sensitive responsive properties of MWCNTs@PS-b-HTPB5-b-PS conductive polymer nanocomposites
Authors: Zhang Rui-Qian , Liu Zhan-Qing , Luo Yan-Ling , Xu Feng , Chen Ya-Shao
Published: July 2019

Novel nanocomposites with improved film-forming properties and responsivity based on the chain-extension of HTPB are prepared for detection of VOCs.
Synthesis of polyhedral gold nanostars as surface-enhanced Raman spectroscopy substrates for measurement of thiram in peach juice
Authors: Sun Lin , Yu Zhilong , Lin Mengshi
Published: July 2019

This study developed a SERS method coupled with polyhedral gold nanostars to detect pesticide residues in juice products.
Colorimetric and fluorescent dual-mode detection of microRNA based on duplex-specific nuclease assisted gold nanoparticle amplification
Authors: Huang Jin , Shangguan Jingfang , Guo Qiuping , Ma Wenjie , Wang Huizhen , Jia Ruichen , Ye Zi , He Xiaoxiao , Wang Kemin
Published: July 2019

Colorimetric and fluorescent dual-mode detection of microRNA based on duplex-specific nuclease assisted gold nanoparticle amplification.
Deposition and morphological evolution of nanostructured palladium during potential cycling: a liquid-cell TEM study
Authors: Yang Jie , Prabhudev Sagar , Andrei Carmen M. , Botton Gianluigi A. , Soleymani Leyla
Published: July 2019

In order to gain better control over the functionality of Pd nanostructures used in several CO2-mitigating electrochemical energy conversion systems, it is imperative to underpin different nanoscale phenomena influencing their structural durability.
Overcoming inaccessibility of fluorinated imines – synthesis of functionalized amines from readily available fluoroacetamides
Authors: Czerwiński Paweł J. , Furman Bartłomiej
Published: July 2019

A direct protocol for the synthesis of functionalized amines from simple fluoroacetic acid-derived amides using Schwartz's reagent was presented.
Zero-strain Na4Fe7(PO4)6 as a novel cathode material for sodium–ion batteries
Authors: Pu Xiangjun , Rong Chao , Tang Shenglong , Wang Huiming , Cao Shunan , Ding Yan , Cao Yuliang , Chen Zhongxue
Published: July 2019

We report for the first time a zero-strain cathode, Na4Fe7(PO4)6, for sodium–ion batteries (SIBs).
Mechanistic insights of Cu(ii)-mediated ortho-C–H amination of arenes by capturing fleeting intermediates and theoretical calculations
Authors: Kumar Manoj , Verma Shalini , Kumar Anubhav , Mishra Pawan K. , Ramabhadran Raghunath O. , Banerjee Shibdas , Verma Akhilesh K.
Published: July 2019

The mechanism of copper-mediated ortho-C–H amination of arenes is investigated by real-time tracking of intermediates and products via online mass spectrometry.
Humid atmospheric pressure plasma jets exposed micro-defects on CoMoO4 nanosheets with enhanced OER performance
Authors: Jiang Haishun , Cui Zhe , Xu Chaoting , Li Wenyao
Published: July 2019

A novel humid APPJs method was adopted to treat CoMoO4 nanosheet arrays resulting in micro-defects and more reaction intermediates that led to an enhanced OER property.
Rhodium(iii)-catalyzed indole synthesis at room temperature using the transient oxidizing directing group strategy
Authors: Shang Yaping , Jonnada Krishna , Yedage Subhash Laxman , Tu Hua , Zhang Xiaofeng , Lou Xin , Huang Shijun , Su Weiping
Published: July 2019

Rh-Catalyzed reactions of N-alkyl anilines with internal alkynes at room temperature have been developed using an in situ generated N-nitroso group as a transient oxidizing directing group.
Enantioselective dearomative [3+2] cycloaddition of 2-nitrobenzofurans with aldehyde-derived Morita–Baylis–Hillman carbonates
Authors: Yang Xin-He , Li Jian-Ping , Wang Dong-Chao , Xie Ming-Sheng , Qu Gui-Rong , Guo Hai-Ming
Published: July 2019

The phosphine-catalyzed asymmetric dearomative [3+2] cycloaddition of 2-nitrobenzofurans with aldehyde-derived MBH carbonates or allenoates was developed.
Integration of a highly monodisperse covalent organic framework photosensitizer with cation exchange synthesized Ag2Se nanoparticles for enhanced phototherapy
Authors: Hu Chunling , Cai Lihan , Liu Sainan , Pang Maolin
Published: July 2019

COF–Ag2Se nanoparticles were synthesized via a cation exchange approach and utilized for combined photodynamic and photothermal therapy.
B(C6F5)3-Catalyzed formal (4+1)-annulation of ortho-quinone methides with diazoacetates: access to 2,3-dihydrobenzofurans
Authors: Xu Guangyang , Tang Shengbiao , Shao Ying , Sun Jiangtao
Published: July 2019

A novel B(C6F5)3-catalyzed formal (4+1)-cycloaddition reaction of alkyne-tethered ortho-quinone methides with diazoacetates has been well established.
Location matters: cooperativity of catalytic partners in porous organic polymers for enhanced CO2 transformation
Authors: Hu Kewei , Tang Yongquan , Cui Jia , Gong Qihan , Hu Changlu , Wang Sai , Dong Ke , Meng Xiangju , Sun Qi , Xiao Feng-Shou
Published: July 2019

Functionalities with corrected inter-site distance in porous materials enable them to work in a concerted manner.
Hydrothermal synthesis of perovskite CaTiO3 tetragonal microrods with vertical V-type holes along the [010] direction
Authors: Chen Tongzhou , Bao Liang , Zheng Yiran , Yang Xin , Ruan Luoyuan , Liu Yong , Xu Gang , Han Gaorong
Published: July 2019

CaTiO3 tetragonal microrods with vertical V-type holes along the [010] direction are synthesized successfully and their growth mechanism is discussed.
Thermodynamics and reaction mechanism of urea decomposition
Authors: Tischer Steffen , Börnhorst Marion , Amsler Jonas , Schoch Günter , Deutschmann Olaf
Published: July 2019

A new reaction mechanism of urea decomposition is proposed after a strict treatment of thermodynamics in all phases.
The folding equilibria of enterobactin enantiomers and their interaction with actinides
Authors: Liu Ziyi , Chai Zhifang , Wang Dongqi
Published: July 2019

The helicity preference of Ent enantiomers was enhanced when binding with Fe3+ while disrupted when binding with actinides.
Interfacial capacitance immunosensing using interdigitated electrodes: the effect of insulation/immobilization chemistry
Authors: Castiello F. Rafael , Porter James , Modarres Paresa , Tabrizian Maryam
Published: July 2019

With the aim of improving the reproducibility of capacitive immunosensors, we performed a comparative study of four different insulating/immobilization chemistries.
Probing hidden colloidal transitions with the assistance of surface plasmons
Authors: Deng Fangfang , Wang Yunxia , Lu Xiaolin , Ding Tao
Published: July 2019

With the assistance of surface plasmons, a vesicle intermediate of Au@PNIPAM clusters is revealed during the cooling cycle, which is due to the co-aggregation of free PNIPAM beads and Au@PNIPAM aggregates in the heating cycle.
Improved Dreiding force field for single layer black phosphorus
Authors: Deng Lijun , Zhou Nian , Tang Shan , Li Ying
Published: July 2019

We present an improved Dreiding force field for single layer black phosphorus (SLBP) obtained by first-principle calculations in conjunction with the particle swarm optimization algorithm and molecular dynamics (MD) simulations.
X-Ray excited luminescence of organo-lanthanide complexes
Authors: Kukinov Andrey A. , Balashova Tatyana V. , Ilichev Vasily A. , Trufanov Alexey N. , Ivin Mikhail N. , Obolensky Sergey V. , Bochkarev Mikhail N.
Published: July 2019

Data on the luminescence of organo-lanthanide complexes excited by X-rays are provided.
A reaction energy profile and fragment attributed molecular system energy change (FAMSEC)-based protocol designed to uncover reaction mechanisms: a case study of the proline-catalysed aldol reaction
Authors: Cukrowski Ignacy , Dhimba George , Riley Darren L.
Published: July 2019

Molecular fragments and their atoms involved in the strongest inter-molecular diatomic and atom–fragment interactions drive a chemical change (explain the reaction mechanism).
Advances in the use of CO2as a renewable feedstock for the synthesis of polymers
Authors: Grignard Bruno , Gennen Sandro , Jérôme Christine , Kleij Arjan W. , Detrembleur Christophe
Published: July 2019

The most relevant approaches to the construction of polymers by exploiting carbon dioxide as a renewable C1 feedstock are highlighted.
Correction: Functional synthetic probes for selective targeting and multi-analyte detection and imaging
Authors: Yue Yongkang , Huo Fangjun , Cheng Fangqin , Zhu Xijing , Mafireyi Tendai , Strongin Robert M. , Yin Caixia
Published: July 2019

Correction for ‘Functional synthetic probes for selective targeting and multi-analyte detection and imaging’ by Yongkang Yue et al., Chem. Soc. Rev., 2019, DOI: 10.1039/c8cs01006d.
Hydride-catalyzed selectively reductive cleavage of unactivated tertiary amides using hydrosilane
Authors: Yao Wubing , Li Rongrong , Yang Jianguo , Hao Feiyue
Published: July 2019

The first hydride-catalyzed reductive cleavage of tertiary amides using the hydrosilane as reducing reagent has been developed. This transition-metal-free process may offer a versatile alternative to current systems for the selective reductive cleavage of amides.
Synthesis, structure and magnetic properties of a series of dinuclear heteroleptic Zn2+/Ln3+ Schiff base complexes: effect of lanthanide ions on the slow relaxation of magnetization
Authors: Boulkedid Ahlem-Linda , Beghidja Adel , Beghidja Chahrazed , Guari Yannick , Larionova Joulia , Long Jérôme
Published: July 2019

We report the synthesis, structure and magnetic properties of a series of heteroleptic Zn2+/Ln3+ complexes of the formula [ZnLClLn(o-van)(H2O)(NO3)]·H2O exhibiting slow relaxation of their magnetization.
In situ formed oxy/hydroxide antennas accelerating the water dissociation kinetics on a Co@N-doped carbon core–shell assembly for hydrogen production in alkaline solution
Authors: Yang Tao , Pei Lang , Yan Shicheng , Yu Zhentao , Yu Tao , Zou Zhigang
Published: July 2019

The hydrogen evolution reaction (HER) in alkaline electrolytes is restricted severely by sluggish water dissociation in the Volmer step.
Cable-like Ru/WNO@C nanowires for simultaneous high-efficiency hydrogen evolution and low-energy consumption chlor-alkali electrolysis
Authors: Zhang Lu-Nan , Lang Zhong-Ling , Wang Yong-Hui , Tan Hua-Qiao , Zang Hong-Ying , Kang Zhen-Hui , Li Yang-Guang
Published: July 2019

An efficient and durable hydrogen evolution electrocatalyst (Ru/WNO@C) in simulated chlor-alkali electrolytes illuminates the prospect of hydrogen and chlor-alkali co-production.
Connecting environmental exposure and neurodegeneration using cheminformatics and high resolution mass spectrometry: potential and challenges
Authors: Schymanski Emma L. , Baker Nancy C. , Williams Antony J. , Singh Randolph R. , Trezzi Jean-Pierre , Wilmes Paul , Kolber Pierre L. , Kruger Rejko , Paczia Nicole , Linster Carole L. , Balling Rudi
Published: July 2019

A multi-disciplinary perspective on connecting chemistry, exposure and medical information to “neurotoxicity” for mass spectrometry-based environmental assessment, including multiple interactive resources for readers to use and explore.
Chronic exposure to graphene oxide (GO) induced inflammation and differentially disturbed the intestinal microbiota in zebrafish
Authors: Jia Pan-Pan , Sun Tai , Junaid Muhammad , Xiong Yang-Hui , Wang Yang-Qing , Liu Li , Pu Shi-Ya , Pei De-Sheng
Published: July 2019

Chronic exposure to GO disrupted the composition of the intestinal microbiota and damaged zebrafish gut tissues accompanied by inflammation responses.
Accelerated Fenton-like kinetics by visible-light-driven catalysis over iron(iii) porphyrin functionalized zirconium MOF: effective promotion on the degradation of organic contaminants
Authors: Wang Lei , Jin Pengxia , Duan Shuhua , Huang Jingwei , She Houde , Wang Qizhao , An Taicheng
Published: July 2019

FeIII–TCPPCl-incorporated UiO-66 MOF could reliably achieve both photocatalysis and a Fenton-like reaction under visible light, with effective degradation against organic pollutants.
Alterations in gut microflora populations and brush border functionality following intra-amniotic administration (Gallus gallus) of wheat bran prebiotic extracts
Authors: Wang Xuan , Kolba Nikolai , Liang Jianfen , Tako Elad
Published: July 2019

Wheat bran is the by-product of milling wheat flour which is one of the richest sources of dietary fiber, and cellulase that can be used for increasing the soluble dietary fiber.
Modelling of SAW-PDMS acoustofluidics: physical fields and particle motions influenced by different descriptions of the PDMS domain
Authors: Ni Zhengyang , Yin Chuhao , Xu Guangyao , Xie Linzhou , Huang Junjie , Liu Shilei , Tu Juan , Guo Xiasheng , Zhang Dong
Published: July 2019

Reduced models of SAW-PDMS acoustofluidics need to be reconsidered especially the neglect of shear waves and interface damping.
Non-lethal growth inhibition by arresting the starch utilization system of clinically relevant human isolates ofBacteroides dorei
Authors: Santilli Anthony D. , Russell Jordan T. , Triplett Eric W. , Whitehead Kristi J. , Whitehead Daniel C.
Published: July 2019

Acarbose elicits potent, non-microbicidal growth inhibition of clinically relevantBacteroides doreistrains by arresting the starch utilization system.
Integrity of zinc finger motifs in PML protein is necessary for inducing its degradation by antimony
Authors: Yang Chang , Hao Rui , Lan Yong Fei , Chen Ye Jia , Wang Chao , Bu Na , Wang Qian Qian , Hussain Liaqat , Ma Li Ya , Maimaitiyiming Yasen , Lu Xiao Yang , Naranmandura Hua
Published: July 2019

Antimony (Sb) belongs to the same group as arsenic (As) in the periodic table, and both share similar characteristics. However, Sb2O3 (SbIII) has no methylation capacity, unlike arsenic trioxide (As2O3). In the present study, we determined the effect of SbIII on NB4 cells and found that antimony could induce PML-RARα fusion protein degradation, reorganization of PML-NBs, and NB4 cell differentiation with low cytotoxicity. On the other hand, zinc finger motifs in PML protein are considered to be a key target binding site for arsenic-induced PML-RARα protein degradation. Interestingly, antimony and arsenic lost their ability to degrade PML-RARα fusion protein in NB4 cells following pretreatment with phenanthroline (i.e., chelator of zinc ions), indicating that the integrity of zinc finger motifs in PML-RARα fusion protein is a fundamental condition for inducing the protein's degradation by antimony and arsenic. Moreover, we found that SbIII could not induce mutant PML (e.g., A126V and L218P) solubility change and degradation, similar to As2O3. In contrast, we found that the organic antimony compound phenylstibine oxide (PSO) could induce mutant PML protein degradation. In conclusion, our results indicate that SbIII might also be a promising agent to treat acute promyelocytic leukemia, in the same manner as As2O3.
First heterobimetallic Cu(i)–dppf complexes designed for anticancer applications: synthesis, structural characterization and cytotoxicity
Authors: Bravo Catarina , Robalo M. Paula , Marques Fernanda , Fernandes Alexandra R. , Sequeira Diogo A. , M. Piedade M. Fátima , Garcia M. Helena , de Brito Maria J. Villa , Morais Tânia S.
Published: July 2019

First heterobimetallic Cu(i)–dppf complexes with bidentate heteroaromatic ligands designed for anticancer applications.
Synthesis of DABCO-based ionic liquid functionalized magnetic nanoparticles as a novel sorbent for the determination of cephalosporins in milk samples by dispersive solid-phase extraction followed by ultra-performance liquid chromatography-tandem mass spectrometry
Authors: Sahebi Hamed , Konoz Elaheh , Ezabadi Ali
Published: July 2019

In this study, DABCO-based ionic liquid-functionalized magnetic iron oxide nanoparticles were synthesized for the first time by the quaternization reaction with 1-(2,3-dihydroxypropyl)-1,4-diazabicyclo[2.2.2]octanylium chloride and chloro-functionalized Fe3O4 nanoparticles.
Facile one-step preparation of ordered mesoporous Ni–M–Al (M = K, Mg, Y, and Ce) oxide catalysts for methane dry reforming
Authors: Zhan Haijuan , Shi Xiaoyan , Ma Baojun , Liu Wanyi , Jiao Xi , Huang Xin
Published: July 2019

Excellent DRM performances of a Ni–Y–Al oxide catalyst is related to the comprehensively advantageous textural properties, such as high Ni dispersion, large surface area, and small Ni nanoparticles inlaid in the honeycomb-like mesoporous skeleton.
Unveiling the potential of scandium complexes for methane C–H bond activation: a computational study
Authors: de Lima Batista Ana Paula , S. de Oliveira-Filho Antonio G. , Braga Ataualpa A. C.
Published: July 2019

Sc(i) complexes activate methane C–H bonds under mild conditions.
Electrospun VSe1.5/CNF composite with excellent performance for alkali metal ion batteries
Authors: Xu Lihong , Xiong Peixun , Zeng Lingxing , Fang Yixing , Liu Renpin , Liu Junbin , Luo Fenqiang , Chen Qinghua , Wei Mingdeng , Qian Qingrong
Published: July 2019

The VSe1.5/CNF composite was fabricated as a superior performance anode material for alkali metal ion batteries.
Analyte-induced disruption of luminescence quenching (AIDLuQ) for femtomolar detection of biomarkers
Authors: Sharma Bipin , Chiluwal Shailendra , Podila Ramakrishna
Published: July 2019

This article demonstrates a novel rapid assay for fluorescence detection of analytes with femtomolar sensitivity using graphene and gold nanoparticles.
Exploring the strength of a hydrogen bond as a function of steric environment using 1,2-azaborine ligands and engineered T4 lysozyme receptors
Authors: Liu Yao , Liu Shih-Yuan
Published: July 2019

The relationship between the steric demand of the ligand and hydrogen bonding strength in the context of ligand–protein binding is revealed using engineered T4 lysozymes as the model biomacromolecules and 1,2-azaborines as ligands.
Star polymers with acid-labile diacetal-based cores synthesized by aqueous RAFT polymerization for intracellular DNA delivery
Authors: Gibson Thomas J. , Smyth Peter , Semsarilar Mona , McCann Aidan P. , McDaid William J. , Johnston Michael C. , Scott Christopher J. , Themistou Efrosyni
Published: July 2019

Facile low temperature aqueous heterogeneous RAFT polymerization for preparation of novel star polymers with acid-labile diacetal-based cores for DNA delivery.
Correction: Surface nanobubbles on the carbonate mineral dolomite
Authors: Owens Camilla L. , Schach Edgar , Rudolph Martin , Nash Geoffrey R.
Published: July 2019

Correction for ‘Surface nanobubbles on the carbonate mineral dolomite’ by Camilla L. Owens et al., RSC Adv., 2018, 8, 35448–35452.
A sterically encumbered photoredox catalyst enables the unified synthesis of the classical lignan family of natural products
Authors: Alfonzo Edwin , Beeler Aaron B.
Published: July 2019

Herein, we detail a unified synthetic approach to the classical lignan family of natural products that hinges on divergence from a common intermediate that was strategically identified from nature's biosynthetic blueprints.
Pushing the analytical limits: new insights into complex mixtures using mass spectra segments of constant ultrahigh resolving power
Authors: Palacio Lozano Diana Catalina , Gavard Remy , Arenas-Diaz Juan P. , Thomas Mary J. , Stranz David D. , Mejía-Ospino Enrique , Guzman Alexander , Spencer Simon E. F. , Rossell David , Barrow Mark P.
Published: July 2019

A new strategy has been developed for characterization of the most challenging complex mixtures to date, using a combination of custom-designed experiments and a new data pre-processing algorithm.
Enhanced water splitting through two-step photoexcitation by sunlight using tantalum/nitrogen-codoped rutile titania as a water oxidation photocatalyst
Authors: Nishioka Shunta , Yanagisawa Kei-ichi , Lu Daling , Vequizo Junie Jhon M. , Yamakata Akira , Kimoto Koji , Inada Miki , Maeda Kazuhiko
Published: July 2019

An improved efficiency of Z-scheme water splitting was demonstrated using tantalum/nitrogen-codoped rutile titania as an O2 evolution photocatalyst.
Controlled reversible buckling of polydopamine spherical microcapsules: revealing the hidden rich phenomena of post-buckling of spherical polymeric shells
Authors: Lei Caifen , Li Qiang , Yang Lu , Deng Fei , Li Jianyao , Ye Zihan , Wang Ying , Zhang Zhenkun
Published: July 2019

Rich post-buckling phenomena of spherical polymeric shells are revealed by controlled reversible buckling of polydopamine spherical microcapsules.
Dynamic wrinkling of freely floating smectic films
Authors: Harth Kirsten , Trittel Torsten , May Kathrin , Stannarius Ralf
Published: July 2019

We demonstrate spontaneous wrinkling as a transient dynamical pattern in thin freely floating smectic liquid-crystalline films.
Conversion pseudocapacitance-contributing and robust hetero-nanostructural perovskite KCo0.54Mn0.46F3 nanocrystals anchored on graphene nanosheet anodes for advanced lithium-ion capacitors, batteries and their hybrids
Authors: Ying Danfeng , Ding Rui , Huang Yongfa , Shi Wei , Xu Qilei , Tan Caini , Sun Xiujuan , Gao Ping , Liu Enhui
Published: July 2019

The pseudocapacitive conversion mechanism and robust perovskite fluorides/graphene hetero-nanostructures contribute to fast rate capability, high specific capacity and superior stability.
Sugar beet hemoglobins: reactions with nitric oxide and nitrite reveal differential roles for nitrogen metabolism
Authors: Leiva Eriksson Nélida , Reeder Brandon J. , Wilson Michael T. , Bülow Leif
Published: July 2019

In contrast with human hemoglobin (Hb) in red blood cells, plant Hbs do not transport oxygen, instead research points towards nitrogen metabolism. Using comprehensive and integrated biophysical methods we characterized three sugar beet Hbs: BvHb1.1, BvHb1.2 and BvHb2. Their affinities for oxygen, CO, and hexacoordination were determined. Their role in nitrogen metabolism was studied by assessing their ability to bind NO, to reduce nitrite (NiR, nitrite reductase), and to form nitrate (NOD, NO dioxygenase). Results show that BvHb1.2 has high NOD-like activity, in agreement with the high nitrate levels found in seeds where this protein is expressed. BvHb1.1, on the other side, is equally capable to bind NO as to form nitrate, its main role would be to protect chloroplasts from the deleterious effects of NO. Finally, the ubiquitous, reactive, and versatile BvHb2, able to adopt ‘open and closed forms’, would be part of metabolic pathways where the balance between oxygen and NO is essential. For all proteins, the NiR activity is relevant only when nitrite is present at high concentrations and both NO and oxygen are absent. The three proteins have distinct intrinsic capabilities to react with NO, oxygen and nitrite; however, it is their concentration which will determine the BvHbs’ activity.
The membrane environment of cadherin adhesion receptors: a working hypothesis
Authors: Teo Jessica L. , Parton Robert G. , Yap Alpha S.
Published: July 2019

Classical cadherin cell adhesion receptors are integral membrane proteins that mediate cell–cell interactions, tissue integrity and morphogenesis. Cadherins are best understood to function as membrane-spanning molecular composites that couple adhesion to the cytoskeleton. On the other hand, the membrane lipid environment of the cadherins is an under-investigated aspect of their cell biology. In this review, we discuss two lines of research that show how the membrane can directly or indirectly contribute to cadherin function. Firstly, we consider how modification of its local lipid environment can potentially influence cadherin signalling, adhesion and dynamics, focusing on a role for phosphoinositide-4,5-bisphosphate. Secondly, we discuss how caveolae may indirectly regulate cadherins by modifying either the lipid composition and/or mechanical tension of the plasma membrane. Thus, we suggest that the membrane is a frontier of cadherin biology that is ripe for re-exploration.
Fluorescence fluctuation spectroscopy: an invaluable microscopy tool for uncovering the biophysical rules for navigating the nuclear landscape
Authors: Priest David G. , Solano Ashleigh , Lou Jieqiong , Hinde Elizabeth
Published: July 2019

Nuclear architecture is fundamental to the manner by which molecules traverse the nucleus. The nucleoplasm is a crowded environment where dynamic rearrangements in local chromatin compaction locally redefine the space accessible toward nuclear protein diffusion. Here, we review a suite of methods based on fluorescence fluctuation spectroscopy (FFS) and how they have been employed to interrogate chromatin organization, as well as the impact this structural framework has on nuclear protein target search. From first focusing on a set of studies that apply FFS to an inert fluorescent tracer diffusing inside the nucleus of a living cell, we demonstrate the capacity of this technology to measure the accessibility of the nucleoplasm. Then with a baseline understanding of the exploration volume available to nuclear proteins during target search, we review direct applications of FFS to fluorescently labeled transcription factors (TFs). FFS can detect changes in TF mobility due to DNA binding, as well as the formation of TF complexes via changes in brightness due to oligomerization. Collectively, we find that FFS-based methods can uncover how nuclear proteins in general navigate the nuclear landscape.
20–50 GHz differential all‐pass networks for phase‐shifting applications
Authors: Anjos E.V.P. , Schreurs D.M.M.‐P. , Vandenbosch G.A.E. , Geurts M.
Published: July 2019

In this Letter, four differential All‐Pass Networks are presented to introduce phase‐shift at millimetre waves using a linear‐phase synthesis procedure. The proposed networks achieve 1‐3.5 dB insertion loss while having across the whole bandwidth, showing an almost constant group‐delay, an RMS gain error of less than 0.15 dB and a phase‐error of less than .
Differentially driven wideband Fabry–Perot cavity antenna
Authors: Gupta Ravi Dutt , Parihar Manoj Singh
Published: July 2019

A wideband differential Fabry–Perot cavity antenna (FPCA) is presented. Unlike the mostly used patch antennas, a rectangular dielectric resonator antenna (DRA) has been investigated as primary radiation source. A compact partially reflective surface (PRS) is proposed and used as superstrate layer over the DRA for wideband gain enhancement. Measurements show that the antenna exhibits a wide impedance bandwidth (for |S11|<−10 dB) as well as half‐power gain bandwidth of 30% ranging from 2.27 to 3.05 GHz with a maximum boresight gain of 9.95 dBi. However, the gain of FPCA is improved all over the band; it is 4.5 dB higher than the DRA's gain at 2.7 GHz. The differential operation provides higher noise immunity than the single‐ended high gain antennas. Furthermore, the presence of DRA and imperfect phase of PRS have been considered for estimation of optimum height of the cavity. Characteristics of a rectangular DRA in a Fabry‐Perot cavity are studied through a detailed parametric study and presented here.
Multi‐objective optimisation‐based active distribution system planning with reconfiguration, intermittent RES, and DSTATCOM
Authors: Sannigrahi Surajit , Roy Ghatak Sriparna , Acharjee Parimal
Published: July 2019

The enormous load growth in recent times has forced distribution companies to undertake comprehensive planning of the active distribution system (ADS) to maintain superior service to their consumers. Under different critical situations in the restructured power system, reconfiguration in combination with the incorporation of renewable energy sources (RESs) and distributed static compensator (DSTATCOM) must be utilised for accurate system planning. In addition, from a practical viewpoint, the time‐variant load demand of different consumers and the intermittency of RES units must be considered. This study proposes a modified multi‐objective particle swarm optimisation (m‐MOPSO) technique for ADS planning considering reconfiguration, RES, and DSTATCOM to enhance voltage stability, reduce pollution, improve reliability, and maximise financial benefits. In the proposed m‐MOPSO, a novel non‐dominant sorting strategy is used to maintain diversity among the non‐dominated solutions. The time‐varying system load, yearly load growth, and intermittent power generation of RES are considered to construct a realistic planning model. The proposed technique is tested on the 33‐bus ADS considering different planning schemes to provide the most suitable planning scheme to the ADS planners. Moreover, the accuracy of the proposed algorithm is confirmed by comparing it with other multi‐objective algorithms.
Non‐linear vector current source for the control of permanent magnet synchronous generators in wave energy applications
Authors: Ramirez Dionisio , Mendonça Hugo , Blanco Marcos , Martinez Fernando
Published: July 2019

A current source with a space‐vector hysteresis band and a constant switching frequency has been designed to be used with surface‐mounted permanent magnet synchronous generators. Its fast response makes it very suitable to carry out the precise control necessary in wave energy converters (WEC). These systems are characterised by large variations of speed, torque (or force) and frequency which means that the control has to cope with large variations of voltage and current and also with persistent periods where these variables present low values. The control system takes into account both rotation direction (or displacement direction, when a linear generator is considered) and electrical sequences, something necessary in WEC such as point absorbers. The algorithm was successfully tested in the laboratory using an ad hoc built emulator, that reproduces the behaviour of an oscillating water‐column‐based WEC. The emulator was built using a similar hardware to those used in equivalent real systems.
Analysis for fractional‐order predator–prey model with uncertainty
Authors: Narayanamoorthy Samayan , Baleanu Dumitru , Thangapandi Kalidas , Perera Shyam Sanjeewa Nishantha
Published: July 2019

Here, the authors analyse the fractional‐order predator–prey model with uncertainty, due to the vast applications in various ecological systems. The most of the ecological model do not have exact analytic solution, so they proposed a numerical technique for an approximate solution. In the proposed method, they have implemented the higher order term into the fractional Euler method to enhance the precise solution. Further, the present attempt is aimed to discuss the solutions of the FPPM with uncertainty (fuzzy) initial conditions. The initial conditions of the predator–prey model were taken as fuzzy initial conditions due to the fact that the ecological model highly depends on uncertain parameters such as growth/decay rate, climatic conditions, and chemical reactions. Finally, the numerical example manifest that the proposed method is authentic, applicable, easy to use from a computational viewpoint and the acquired outcomes are balanced with the existing method (HPM), which shows the efficiency of the proposed method.
Dynamic average modelling of renewable generation sources for real time simulation
Authors: Nzimako Onyinyechi , Jegues Christian , Zhang Yi
Published: July 2019

The increase in microgrids and smart grid research comprising renewable generation sources with advanced grid control functionalities is driving the need for sophisticated simulation and hardware in the loop (HIL) test facilities using digital real time simulators (DRTS). Unlike traditional off line simulation tools, DRTS provides fast, continuous real time operation as well as hardware interfaces to test the operation of physical control, protection and power devices before they are installed in the smart/micro grid application. The available computation resources of the DRTS to achieve fast, continuous real time operation impose a limitation on the size and level of detail of the power system model for the simulation and HIL application. Reduced dynamic models that represent the power system and control dynamics with sufficient accuracy provide an acceptable trade‐off between the required computation resources and size of the power system model for large simulation applications. This paper discusses the dynamic average modelling of renewable energy generation sources for real time simulation applications.
Communicating radar using frequency‐shift keying and fractional Fourier transform for automotive applications
Authors: Striano Pasquale , Ilioudis Christos V. , Clemente Carmine , Soraghan John J.
Published: July 2019

Modern radar applications, such as automotive, integration of radar and communications, have become an important requirement. Systems able to provide joint radar and communications would exploit the same hardware while providing enhanced capabilities to the carrying platform, such as road situation awareness and content sharing. In this article, a novel framework for automotive radars based on the fractional Fourier transform (FrFT) is introduced. The aim of the proposed approach is to preserve radar performance while integrating a communication link. Simulation results demonstrate the potential of the proposed framework for automotive applications.
SAR image detection of sea targets based on two‐step CFAR detector of KK distribution
Authors: Jie Song , Fu‐qing Cai , Heng‐yan Liu , Wei Xiong
Published: July 2019

In the detection of SAR image of sea targets, the simple statistical distribution models such as Gaussian distribution, normal distribution, Weibull distribution etc. are obviously not suitable for the fitting of the background clutter of missile‐borne SAR images. The target of the sea surface in SAR image usually has a heavy tail caused by the sea spike, while the KK distribution can better fit it. A two‐stage CFAR detector with KK distribution is designed. The results show that KK distribution can fit the data well and the two‐stage CFAR detector based on the KK distribution has good performances.
Constant false alarm rate detection method in polarimetric synthetic aperture radar imagery based on whitening filter under inverse beta distribution
Authors: MingChun Wang , JiaFeng Zhang , Tao Liu
Published: July 2019

The constant false alarm rate (CFAR) detection method based on multi‐look polarisation whitening filter (MPWF) has not been obtained in the polarimetric synthetic aperture radar imagery when the texture variable obeys the Inverse Beta distribution. To solve the problem, a new CFAR detection method with analytical expression for false alarm rate is proposed. First, the probability density function (PDF) of the output via MPWF is derived based on the hypothesis of the texture variables obeying the Inverse Beta distribution in the product model. Secondly, the analytical expression of false alarm rate about detection threshold is obtained by integrating the PDF of MPWF output, and the procedure of the CFAR detection method is designed. Finally, the performance comparisons are made among the new method, Wishart CFAR detection algorithm and the two‐parameter CFAR method via simulated and real data of AIRSAR. The results show that figure of merit of the new method is the highest and the new method gives the best performance in Inverse Beta distribution case.
H-band discovery of additional second-generation stars in the Galactic bulge globular cluster NGC 6522 as observed by APOGEE and Gaia
Authors: Fernández-Trincado J. G. , Zamora O. , Souto Diogo , Cohen R. E. , Dell’Agli F. , García-Hernández D. A. , Masseron T. , Schiavon R. P. , Mészáros Sz. , Cunha K. , Hasselquist S. , Shetrone M. , Schiappacasse Ulloa J. , Tang B. , Geisler D. , Schleicher D. R. G. , Villanova S. , Mennickent R. E. , Minniti D. , Alonso-García J. , Manchado A. , Beers T. C. , Sobeck J. , Zasowski G. , Schultheis M. , Majewski S. R. , Rojas-Arriagada A. , Almeida A. , Santana F. , Oelkers R. J. , Longa-Peña P. , Carrera R. , Burgasser A. J. , Lane R. R. , Roman-Lopes A. , Ivans I. I. , Hearty F. R.
Published: July 2019

We present an elemental abundance analysis of high-resolution spectra for five giant stars spatially located within the innermost regions of the bulge globular cluster NGC 6522 and derive Fe, Mg, Al, C, N, O, Si, and Ce abundances based on H-band spectra taken with the multi-object APOGEE-north spectrograph from the SDSS-IV Apache Point Observatory Galactic Evolution Experiment (APOGEE) survey. Of the five cluster candidates, two previously unremarked stars are confirmed to have second-generation (SG) abundance patterns, with the basic pattern of depletion in C and Mg simultaneous with enrichment in N and Al as seen in other SG globular cluster populations at similar metallicity. In agreement with the most recent optical studies, the NGC 6522 stars analyzed exhibit (when available) only mild overabundances of the s-process element Ce, contradicting the idea that NGC 6522 stars are formed from gas enriched by spinstars and indicating that other stellar sources such as massive AGB stars could be the primary polluters of intra-cluster medium. The peculiar abundance signatures of SG stars have been observed in our data, confirming the presence of multiple generations of stars in NGC 6522.
On-axis view of GRB 170817A
Authors: Salafia O. S. , Ghirlanda G. , Ascenzi S. , Ghisellini G.
Published: July 2019

The peculiar short gamma-ray burst (SGRB) GRB 170817A has been firmly associated to the gravitational wave event GW170817, which has been unanimously interpreted as due to the coalescence of a double neutron star binary. The unprecedented behaviour of the non-thermal afterglow led to a debate over its nature, which was eventually settled by high-resolution VLBI observations that strongly support the off-axis structured jet scenario. Using information on the jet structure derived from multi-wavelength fitting of the afterglow emission and of the apparent VLBI image centroid motion, we compute the appearance of a GRB 170817A-like jet as seen by an on-axis observer and compare it to the previously observed population of SGRB afterglows and prompt emission events. We find that the intrinsic properties of the GRB 170817A jet are representative of a typical event in the SGRB population, hinting at a quasi-universal jet structure. The diversity in the SGRB afterglow population could therefore be ascribed in large part to extrinsic (redshift, density of the surrounding medium, viewing angle) rather than intrinsic properties. Although more uncertain, the comparison can be extended to the prompt emission properties, leading to similar conclusions.
COSMOGRAIL
Authors: Bonvin V. , Millon M. , Chan J. H.-H. , Courbin F. , Rusu C. E. , Sluse D. , Suyu S. H. , Wong K. C. , Fassnacht C. D. , Marshall P. J. , Treu T. , Buckley-Geer E. , Frieman J. , Hempel A. , Kim S. , Lachaume R. , Rabus M. , Chao D. C.-Y. , Chijani M. , Gilman D. , Gilmore K. , Rojas K. , Williams P. , Anguita T. , Kochanek C. S. , Morgan C. , Motta V. , Tewes M. , Meylan G.
Published: July 2019

We present new measurements of the time delays of WFI2033−4723. The data sets used in this work include 14 years of data taken at the 1.2 m Leonhard Euler Swiss telescope, 13 years of data from the SMARTS 1.3 m telescope at Las Campanas Observatory and a single year of high-cadence and high-precision monitoring at the MPIA 2.2 m telescope. The time delays measured from these different data sets, all taken in the R-band, are in good agreement with each other and with previous measurements from the literature. Combining all the time-delay estimates from our data sets results in ΔtAB = 36.2+0.7−0.8 days (2.1% precision), ΔtAC = −23.3+1.2−1.4 days (5.6%) and ΔtBC = −59.4+1.3−1.3 days (2.2%). In addition, the close image pair A1-A2 of the lensed quasars can be resolved in the MPIA 2.2 m data. We measure a time delay consistent with zero in this pair of images. We also explore the prior distributions of microlensing time-delay potentially affecting the cosmological time-delay measurements of WFI2033−4723. Our time-delay measurements are not precise enough to conclude that microlensing time delay is present or absent from the data. This work is part of a H0LiCOW series focusing on measuring the Hubble constant from WFI2033−4723.
Simulation model of single structured tower hybrid wind and tidal energy cultivation based on Yemen’s south west coast
Authors: Alfakih Sadeq M. , De Tian , Jawad Ali Shah Syed , Aneeq  , Hayat Khuram
Published: July 2019

This paper propose the single structured tower with hybrid renewable energy cultivation on south west coast of Yemen by the means of tidal turbine which uses ocean current under the ocean and at the top of tower is wind turbine to harvest the maximum available energy resources at the same site. This single structured turbine is an efficient and cost effective way to utilize the renewable resources available at the case study area of Yemen. The meteorological analysis is also considered to increase the efficiency of this renewable energy unit as well as the Matlab simulation of generation unit is being carried out to observe the behavior of renewable sources (wind, tide current) on turbine.
Simulation of large-scale energy storage to improve high-voltage DC stability
Authors: He Guoxin , Lu Hongshui , Yang Dongmei , Chen Yonghua , Du Wei
Published: July 2019

Study on large-scale electrochemical energy storage simulation is carried out in this paper to discuss its feasibility in enhancing the stability of HVDC power transmission, thus providing a reference for large-scale energy storage planning and design in the background of global energy internet. The paper introduces the development status quo of the large-scale energy storage technology, and provides an analysis of the active and inactive power features after HVDC commutation failure by establishing a large-scale energy storage model and a HVDC power transmission system commutation failure model, thereby exploring the configuration feasibility of the large-scale energy storage technology; Then, a simulation analysis is given on the effect of large-scale energy storage on HVDC power transmission fault features; Finally, a prospect was expected towards the application tendency of large-scale energy storage in global energy internet.