bluuebunny/crossref_metadata_2025 huggingface dataset:
High spatial resolution nanoslit SERS for single-molecule nucleobase sensing
Authors: Chen Chang , Li Yi , Kerman Sarp , Neutens Pieter , Willems Kherim , Cornelissen Sven , Lagae Liesbet , Stakenborg Tim , Van Dorpe Pol
Published: April 2018

Solid-state nanopores promise a scalable platform for single-molecule DNA analysis. Direct, real-time identification of nucleobases in DNA strands is still limited by the sensitivity and the spatial resolution of established ionic sensing strategies. Here, we study a different but promising strategy based on optical spectroscopy. We use an optically engineered elongated nanopore structure, a plasmonic nanoslit, to locally enable single-molecule surface enhanced Raman spectroscopy (SERS). Combining SERS with nanopore fluidics facilitates both the electrokinetic capture of DNA analytes and their local identification through direct Raman spectroscopic fingerprinting of four nucleobases. By studying the stochastic fluctuation process of DNA analytes that are temporarily adsorbed inside the pores, we have observed asynchronous spectroscopic behavior of different nucleobases, both individual and incorporated in DNA strands. These results provide evidences for the single-molecule sensitivity and the sub-nanometer spatial resolution of plasmonic nanoslit SERS.
Direct binding of CEP85 to STIL ensures robust PLK4 activation and efficient centriole assembly
Authors: Liu Yi , Gupta Gagan D. , Barnabas Deepak D. , Agircan Fikret G. , Mehmood Shahid , Wu Di , Coyaud Etienne , Johnson Christopher M. , McLaughlin Stephen H. , Andreeva Antonina , Freund Stefan M. V. , Robinson Carol V. , Cheung Sally W. T. , Raught Brian , Pelletier Laurence , van Breugel Mark
Published: April 2018

Centrosomes are required for faithful chromosome segregation during mitosis. They are composed of a centriole pair that recruits and organizes the microtubule-nucleating pericentriolar material. Centriole duplication is tightly controlled in vivo and aberrations in this process are associated with several human diseases, including cancer and microcephaly. Although factors essential for centriole assembly, such as STIL and PLK4, have been identified, the underlying molecular mechanisms that drive this process are incompletely understood. Combining protein proximity mapping with high-resolution structural methods, we identify CEP85 as a centriole duplication factor that directly interacts with STIL through a highly conserved interaction interface involving a previously uncharacterised domain of STIL. Structure-guided mutational analyses in vivo demonstrate that this interaction is essential for efficient centriolar targeting of STIL, PLK4 activation and faithful daughter centriole assembly. Taken together, our results illuminate a molecular mechanism underpinning the spatiotemporal regulation of the early stages of centriole duplication.
Multi-omics profiling of younger Asian breast cancers reveals distinctive molecular signatures
Authors: Kan Zhengyan , Ding Ying , Kim Jinho , Jung Hae Hyun , Chung Woosung , Lal Samir , Cho Soonweng , Fernandez-Banet Julio , Lee Se Kyung , Kim Seok Won , Lee Jeong Eon , Choi Yoon-La , Deng Shibing , Kim Ji-Yeon , Ahn Jin Seok , Sha Ying , Mu Xinmeng Jasmine , Nam Jae-Yong , Im Young-Hyuck , Lee Soohyeon , Park Woong-Yang , Nam Seok Jin , Park Yeon Hee
Published: April 2018

Breast cancer (BC) in the Asia Pacific regions is enriched in younger patients and rapidly rising in incidence yet its molecular bases remain poorly characterized. Here we analyze the whole exomes and transcriptomes of 187 primary tumors from a Korean BC cohort (SMC) enriched in pre-menopausal patients and perform systematic comparison with a primarily Caucasian and post-menopausal BC cohort (TCGA). SMC harbors higher proportions of HER2+ and Luminal B subtypes, lower proportion of Luminal A with decreased ESR1 expression compared to TCGA. We also observe increased mutation prevalence affecting BRCA1, BRCA2, and TP53 in SMC with an enrichment of a mutation signature linked to homologous recombination repair deficiency in TNBC. Finally, virtual microdissection and multivariate analyses reveal that Korean BC status is independently associated with increased TIL and decreased TGF-β signaling expression signatures, suggesting that younger Asian BCs harbor more immune-active microenvironment than western BCs.
Structural basis for energy transduction by respiratory alternative complex III
Authors: Sousa Joana S. , Calisto Filipa , Langer Julian D. , Mills Deryck J. , Refojo Patrícia N. , Teixeira Miguel , Kühlbrandt Werner , Vonck Janet , Pereira Manuela M.
Published: April 2018

Electron transfer in respiratory chains generates the electrochemical potential that serves as energy source for the cell. Prokaryotes can use a wide range of electron donors and acceptors and may have alternative complexes performing the same catalytic reactions as the mitochondrial complexes. This is the case for the alternative complex III (ACIII), a quinol:cytochrome c/HiPIP oxidoreductase. In order to understand the catalytic mechanism of this respiratory enzyme, we determined the structure of ACIII from Rhodothermus marinus at 3.9 Å resolution by single-particle cryo-electron microscopy. ACIII presents a so-far unique structure, for which we establish the arrangement of the cofactors (four iron–sulfur clusters and six c-type hemes) and propose the location of the quinol-binding site and the presence of two putative proton pathways in the membrane. Altogether, this structure provides insights into a mechanism for energy transduction and introduces ACIII as a redox-driven proton pump.
Author Correction: Patch clamp-assisted single neuron lipidomics
Authors: Merrill Collin B. , Basit Abdul , Armirotti Andrea , Jia Yousheng , Gall Christine M. , Lynch Gary , Piomelli Daniele
Published: April 2018

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
Author Correction: Comparison of quality of life between Billroth-І and Roux-en-Y anastomosis after distal gastrectomy for gastric cancer: A randomized controlled trial
Authors: Yang Kun , Zhang Wei-Han , Liu Kai , Chen Xin-Zu , Zhou Zong-Guang , Hu Jian-Kun
Published: April 2018

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
Publisher Correction: Human single chain-transbodies that bound to domain-I of non-structural protein 5A (NS5A) of hepatitis C virus
Authors: Glab-ampai Kittirat , Chulanetra Monrat , Malik Aijaz Ahmad , Juntadech Thanate , Thanongsaksrikul Jeeraphong , Srimanote Potjanee , Thueng-in Kanyarat , Sookrung Nitat , Tongtawe Pongsri , Chaicumpa Wanpen
Published: April 2018

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
Elevated urinary N-acetyl-β-D-glucosaminidase is associated with high glycoalbumin-to-hemoglobin A1c ratio in type 1 diabetes patients with early diabetic kidney disease
Authors: Hong Namki , Lee Minyoung , Park Soyoung , Lee Yong-ho , Jin Sang-Man , Kim Jae Hyeon , Lee Byung-Wan
Published: April 2018

Urinary N-acetyl-β-D-glucosaminidase (uNAG) predicted the progression of diabetic kidney disease (DKD) prior to development of albuminuria in diabetes patients. We sought whether uNAG level is associated with glycoalbumin-to-hemoglobin A1c ratio (G/A ratio), a marker of postprandial hyperglycemia and glycemic excursion, independent of albuminuria and kidney function. The association between uNAG excretion and G/A ratio was assessed in 204 consecutive subjects with type 1 diabetes (T1D) (mean age 43.9 years; 49.0% men). uNAG excretion level increased along with older age, hyperglycemia, and degree of albuminuria, but was not correlated with body mass index or estimated glomerular filtration rate (eGFR). Elevated uNAG showed robust association with higher G/A ratio (adjusted β = 0.103, P = 0.020) after adjustment for age, sex, body mass index, duration of diabetes, uACR, angiotensin blockers use, fasting plasma glucose, and hemoglobin level. uNAG showed better discriminatory performance for individuals with high G/A ratio than albuminuria (AUC 0.613 vs. 0.518, P = 0.038). Measurement of uNAG improved AUC for high G/A ratio from 0.699 to 0.748 (P = 0.043) when added to conventional risk factors (cutoff 5.24 U/g creatinine; sensitivity 62.5% and specificity 58.0%). In conclusion, Elevated uNAG was found to be associated with high G/A ratio in patients with T1D with early stage DKD, independent of age and albuminuria.
Liquid-Liquid Phase Separation of Patchy Particles Illuminates Diverse Effects of Regulatory Components on Protein Droplet Formation
Authors: Nguemaha Valery , Zhou Huan-Xiang
Published: April 2018

Recently many cellular functions have been associated with membraneless organelles, or protein droplets, formed by liquid-liquid phase separation (LLPS). Proteins in these droplets often contain RNA-binding domains, but the effects of RNA on LLPS have been controversial. To gain better understanding on the roles of RNA and other macromolecular regulators, here we used Gibbs-ensemble simulations to determine phase diagrams of two-component patchy particles, as models for mixtures of proteins with regulatory components. Protein-like particles have four patches, with attraction strength εPP; regulatory particles experience mutual steric repulsion but have two attractive patches toward proteins, with the strength εPR tunable. At low εPR, the regulator, due to steric repulsion, preferentially partitions in the dispersed phase, thereby displacing the protein into the droplet phase and promoting LLPS. At moderate εPR, the regulator starts to partition and displace the protein in the droplet phase, but only to weaken bonding networks and thereby suppress LLPS. At εPR > εPP, the enhanced bonding ability of the regulator initially promotes LLPS, but at higher amounts, the resulting displacement of the protein suppresses LLPS. These results illustrate how RNA can have disparate effects on LLPS, thus able to perform diverse functions in different organelles.
TMS Over the Cerebellum Interferes with Short-term Memory of Visual Sequences
Authors: Ferrari C. , Cattaneo Z. , Oldrati V. , Casiraghi L. , Castelli F. , D’Angelo E. , Vecchi T.
Published: April 2018

Growing evidence suggests that the cerebellum is not only involved in motor functions, but it significantly contributes to sensory and cognitive processing as well. In particular, it has been hypothesized that the cerebellum identifies recurrent serial events and recognizes their violations. Here we used transcranial magnetic stimulation (TMS) to shed light on the role of the cerebellum in short-term memory of visual sequences. In two experiments, we found that TMS over the right cerebellar hemisphere impaired participants’ ability to recognize the correct order of appearance of geometrical stimuli varying in shape and/or size. In turn, cerebellar TMS did not affect recognition of highly familiar short sequences of letters or numbers. Overall, our data suggest that the cerebellum is involved in memorizing the order in which (concatenated) stimuli appear, this process being important for sequence learning.
Properties of the ternary complex formed by yeast eIF4E, p20 and mRNA
Authors: Arndt Nick , Ross-Kaschitza Daniela , Kojukhov Artyom , Komar Anton A. , Altmann Michael
Published: April 2018

Yeast p20 is a small, acidic protein that binds eIF4E, the cap-binding protein. It has been proposed to affect mRNA translation and degradation, however p20′s function as an eIF4E-binding protein (4E-BP) and its physiological significance has not been clearly established. In this paper we present data demonstrating that p20 is capable of binding directly to mRNA due to electrostatic interaction of a stretch of arginine and histidine residues in the protein with negatively charged phosphates in the mRNA backbone. This interaction contributes to formation of a ternary eIF4E/p20/capped mRNA complex that is more stable than complexes composed of capped mRNA bound to eIF4E in the absence of p20. eIF4E/p20 complex was found to have a more pronounced stimulatory effect on capped mRNA translation than purified eIF4E alone. Addition of peptides containing the eIF4E-binding domains present in p20 (motif  YTIDELF), in eIF4G (motif  YGPTFLL) or Eap1 (motif  YSMNELY) completely inhibited eIF4E-dependent capped mRNA translation (in vitro), but had a greatly reduced inhibitory effect when eIF4E/p20 complex was present. We propose that the eIF4E/p20/mRNA complex serves as a stable depository of mRNAs existing in a dynamic equilibrium with other complexes such as eIF4E/eIF4G (required for translation) and eIF4E/Eap1 (required for mRNA degradation).
An ultra-broadband perovskite-PbS quantum dot sensitized carbon nanotube photodetector
Authors: Ka Ibrahima , Gerlein Luis F. , Asuo Ivy M. , Nechache Riad , Cloutier Sylvain G.
Published: April 2018

A nano-engineered hybrid material consisting of SWCNTs, PbS-QDs and a halide perovskite is developed for the first time. The PbS-QDs in the hybrid system are found to be a charge generator and a charge-transfer facilitator. The hybrid material integrated into photoconductive devices shows a broad spectral response.
Asymmetric transfer hydrogenation reactions of N-sulfonylimines by using alcohols as hydrogen sources
Authors: Yang Fan , Chen Jingchao , Shen Guoli , Zhang Xuexin , Fan Baomin
Published: April 2018

A palladium/zinc co-catalytic system was established and successfully utilized in the asymmetric transfer hydrogenation reactions of N-sulfonylimines with alcohols as hydrogen sources.
Remarkable high efficiency of red emitters using Eu(iii) ternary complexes
Authors: Kalyakina Alena S. , Utochnikova Valentina V. , Zimmer Manuel , Dietrich Fabian , Kaczmarek Anna M. , Van Deun Rik , Vashchenko Andrey A. , Goloveshkin Alexander S. , Nieger Martin , Gerhards Markus , Schepers Ute , Bräse Stefan
Published: April 2018

We have synthesized Eu(iii) ternary complexes possessing record photoluminescence yields up to 90%.
Local crystal structure in the vicinity of Cr in doped AlN thin films studied by X-ray absorption spectroscopy
Authors: Panda Padmalochan , Ramaseshan R. , Sahoo Madhusmita , Krishna Nanda Gopala , Yadav A. K. , Jha S. N. , Bhattacharyya D.
Published: April 2018

This article reports the detailed X-ray absorption spectroscopy (XAS) study of Al1−xCrxN (x= 4, 6, 11%) thin films synthesized by the reactive magnetron co-sputtering technique.
Mechanistic insights into the photogeneration and quenching of guanine radical cationviaone-electron oxidation of G-quadruplex DNA
Authors: Yang Yumei , Yang Wenjing , Su Hongmei , Fang Weihai , Chen Xuebo
Published: April 2018

Selectivity of activation site for the photogeneration and quenching of guanine radical cation was elucidated by the analysis of the relaxation paths of one-electron oxidation of G-quadruplex DNA.
Photoinduced proton transfer inside an engineered green fluorescent protein: a stepwise–concerted-hybrid reaction
Authors: Tang Longteng , Wang Yanli , Zhu Liangdong , Kallio Karen , Remington S. James , Fang Chong
Published: April 2018

The photoinduced proton transfer inside an engineered GFP double mutant is a stepwise–concerted-hybrid reaction revealed by tunable ultrafast Raman spectroscopy.
H5PV2Mo10O40 encapsulated in MIL-101(Cr): facile synthesis and characterization of rationally designed composite materials for efficient decontamination of sulfur mustard
Authors: Li Yanqin , Gao Qi , Zhang Lijuan , Zhou Yunshan , Zhong Yuxu , Ying Ying , Zhang Mingcai , Huang Chunqian , Wang Yong'an
Published: April 2018

A newly synthesized composite H5PV2Mo10O40@MIL-101(Cr) can decontaminate HD quickly and efficiently owing to the synergetic combination of the components.
Interfacial benzenethiol modification facilitates charge transfer and improves stability of cm-sized metal halide perovskite solar cells with up to 20% efficiency
Authors: Lu Jianfeng , Lin Xiongfeng , Jiao Xuechen , Gengenbach Thomas , Scully Andrew D. , Jiang Liangcong , Tan Boer , Sun Jingsong , Li Bin , Pai Narendra , Bach Udo , Simonov Alexandr N. , Cheng Yi-Bing
Published: April 2018

A facile method to produce metal halide perovskite solar cells with improved stability and efficiency.
Realizing the nanoscale quantitative thermal mapping of scanning thermal microscopy by resilient tip–surface contact resistance models
Authors: Li Yifan , Mehra Nitin , Ji Tuo , Zhu Jiahua
Published: April 2018

Quantitative assessment of thermal properties by scanning thermal microscopy (SThM) is a demanded technology, but still not yet available due to the presence of unpredictable thermal contact resistance (TCR) at the tip/substrate interface.
Single glucose molecule transport process revealed by force tracing and molecular dynamics simulations
Authors: Pan Yangang , Zhang Yuebin , Gongpan Pianchou , Zhang Qingrong , Huang Siteng , Wang Bin , Xu Bingqian , Shan Yuping , Xiong Wenyong , Li Guohui , Wang Hongda
Published: April 2018

Single-molecule glucose transport was illuminated using both experimental and theoretical methods.
Postsynthetic modification of single Pd sites into uncoordinated polypyridine groups of a MOF as the highly efficient catalyst for Heck and Suzuki reactions
Authors: Dong Dapeng , Li Zhenghua , Liu Dedi , Yu Naisen , Zhao Haiyan , Chen Huiying , Liu Jia , Liu Dongping
Published: April 2018

A novel Pd-HoMOF catalyst was prepared, which displayed good thermal stability and high activity in Heck and Suzuki cross-coupling reactions.
Ionic effects on the mechanical and swelling properties of a poly(acrylic acid/acrylamide) double crosslinking hydrogel
Authors: Zhang Huijuan , Cheng Yuran , Hou Xinjuan , Yang Biao , Guo Fang
Published: April 2018

A P(AA/AM)–Fe(NO3)3 double crosslinking gel showed a superior tensile strength of 1471 kPa compared to those of all other metal salts tested, which was demonstrated by molecular simulation to result from the stronger hydrogen bonding in this metal–(COO)n complex.
Designed synthesis of ultrafine NiO nanocrystals bonded on a three dimensional graphene framework for high-capacity lithium-ion batteries
Authors: Chen Jiayuan , Wu Xiaofeng , Tan Qiangqiang , Chen Yunfa
Published: April 2018

NiO nanocrystals/3D-GF nanohybrids are fabricated in situ and used for high-capacity lithium-ion batteries.
The correlation between gelatin macroscale differences and nanoparticle properties: providing insight into biopolymer variability
Authors: Stevenson André T. , Jankus Danny J. , Tarshis Max A. , Whittington Abby R.
Published: April 2018

Higher gelatin molecular weight distributions produce larger nanoparticle diameters, which is independent of gelatin type.
Atomic-scale understanding of high thermal stability of the Mo/CoFeB/MgO spin injector for spin-injection in remanence
Authors: Tao Bingshan , Barate Philippe , Devaux Xavier , Renucci Pierre , Frougier Julien , Djeffal Abdelhak , Liang Shiheng , Xu Bo , Hehn Michel , Jaffrès Henri , George Jean-Marie , Marie Xavier , Mangin Stéphane , Han Xiufeng , Wang Zhanguo , Lu Yuan
Published: April 2018

Remanent spin injection into GaAs based LEDs with a thermally stable Mo/CoFeB/MgO spin injector.
Polymerization-induced self-assembly of large-scale iohexol nanoparticles as contrast agents for X-ray computed tomography imaging
Authors: Ding Yuxun , Zhang Xinyu , Xu Yingjin , Cheng Tangjian , Ou Hanlin , Li Zhanyong , An Yingli , Shen Wenzeng , Liu Yang , Shi Linqi
Published: April 2018

Fundamental research for CT imaging, in which iohexol nanoparticles (INPs) were synthesised using a one-pot strategy via polymerization-induced self-assembly (PISA).
Journal of Materials Chemistry B Editor's choice web collection: ‘‘Seeing the unseen updated: advances in biosensing’’
Authors: Qu Xiaogang
Published: April 2018

Xiaogang Qu introduces a Journal of Materials Chemistry B Editor's choice web collection on advances in biosensing (http://rsc.li/BiosensorsAdvances).
High‐frequency InAlN/GaN HFET with fmax over 400 GHz
Authors: Fu Xing‐Chang , Lv Yuanjie , Zhang Li‐Jiang , Zhang Tong , Li Xian‐Jie , Song Xubo , Zhang Zhirong , Fang Yulong , Feng Zhihong
Published: April 2018

Ultra‐thin InAlN/GaN heterostructure field‐effect transistors (HFETs) having high maximum oscillation frequency (fmax) are fabricated by scaling lateral dimensions. A 3 nm GaN cap layer is adopted to reduce the electron density and suppress the short‐channel effects. Non‐alloyed regrown n+‐GaN ohmic contacts with total ohmic resistance (Rtot) of 0.13 Ω.mm is also introduced into the device, in which the virtual source‐to‐drain distance is 600 nm. T‐shaped gate with 40 nm length is formed in the centre of the source‐to‐drain region by self‐aligned e‐beam lithography. The peak extrinsic transconductance (gm) reaches 956 mS/mm. Most of all, a high fmax of 405 GHz is obtained, which is the highest value among the reported InAlN/GaN HFETs. These obtained results mean that the InAlN/GaN HFETs having reliability should be still suitable for G‐band (140–220 GHz) power‐amplifier application with further optimisation.
Integral‐series Fourier analysis of chaotic PWM patterns for common mode voltage stresses
Authors: Asefi Mahdi , Nazarzadeh Jalal
Published: April 2018

In this study, the theory of pulse width modulation (PWM) is developed for both sine‐wave PWM (SPWM) and chaotic sine‐wave PWM (CSPWM). In SPWM, power spectra are analysed by an analytical method such as double Fourier series (DFS) technique, and the integral‐series Fourier method is fully devised and analytically theorised for CSPWM. It is shown that the root‐mean‐square value of inverter's zero‐sequence voltage does not rely on carrier and reference frequency in fixed‐frequency SPWM, while in CSPWM, this depends on frequency modulating gain and chaotic sequence of numbers. Also, the computation time of purely numerical harmonic analysis can be much heavier than analytical ones. Furthermore, the DFS and integral‐series Fourier methods are applied to SPWM and CSPWM with two different frame sizes of squirrel cage motors for the shaft voltage and the electro‐magnetic interference (EMI). The numerical and experimental results show that CSPWM can have positive effect on the shaft voltage while it definitely weakens the EMI problems.
Volt‐ampere ratings in electronically tuned linear alternators for thermoacoustic engines
Authors: Iacchetti Matteo F. , Shuttleworth Roger , Zhang Min
Published: April 2018

Linear alternators (LAs) coupled to thermoacoustic engines (TAEs) provide a viable solution to extract energy from a heat source in a variety of applications such as waste heat, energy harvesting, solar thermal and biomass power generation. For the electrical power to be maximised, the acoustic impedances of LA and TAE have to match. This requirement cannot, in general, be met by relying only on the design of the LA, but can be achieved at the control level, by using a fraction of the LA inverter current to create ‘electronic stiffness’ which contributes to the overall stiffness tuning the resonance frequency. The same concept can, in principle, be used to replace part of the mechanical spring stiffness in order to overcome the limitations in the mechanical design, at the expense of an increase in LA and inverter ratings. The impact of electronic stiffness on LA power capability and ratings is analysed here. Two meaningful scenarios are considered in the analysis: the LA derating for resonance frequency tuning and the oversizing when springs are partially replaced by electronic stiffness. The study is supplemented with experiments on a small‐scale LA test rig.
Cost–benefit analysis of rooftop photovoltaic systems based on climate conditions of Gulf Cooperation Council countries
Authors: Saker Nathalie , Al‐Qattan Ayman , Al‐Otaibi Ahmad , Al‐Mulla Ahmad
Published: April 2018

The objective of this study is to present an economic analysis (EA) of actual installed photovoltaic (PV) projects considering Gulf Cooperation Council countries climate conditions. The two analysed PV systems are commissioned in Kuwait and they were chosen to be the scope of this study since the availability of their characteristics. The first system is installed on a school and equipped with thin film (copper indium gallium selenide) solar modules of efficiency equal to 14% and the other system is installed on a commercial building and equipped with monocrystalline solar modules of efficiency equal to 17%. The EA consists of studying the financial parameters related to the two previous projects using two different calculation tools. One tool is developed and presented in this study that is the EA calculator and the other tool is the existing solar advisory model software. The two calculation tools’ results almost match with slight differences considered negligible, so the developed EA calculator is considered validated. As a conclusion, the impact of renewable energy (RE) costs on future investments in RE technologies and especially on PV projects is being evaluated.
Robust nested loop control scheme for LCL‐filtered inverter‐based DG unit in grid‐connected and islanded modes
Authors: Buduma Parusharamulu , Panda Gayadhar
Published: April 2018

The grid feeding and grid forming inverters are important candidates in grid connected and islanded modes (IMs) of microgrid system, respectively. The grid feeding inverter supplies the preset power during grid‐connected mode and the grid forming inverter generates a reference voltage for other distributed generation (DG) interfacing inverters in IM. In such scenario, the proper control of these inverters is an utmost importance. Generally, a nested loop control strategy uses a conventional PI controller for the inner and outer loops of grid feeding and grid forming inverter, but it gives deteriorative performance under parameter uncertainty condition. This study proposes a robust nested loop control scheme with the mixed optimal controller in the outer voltage control loop and the robust linear quadratic regulator (LQR) state feedback controller in the inner current control loop for the smooth operation of the system in both modes. The simulation and experimental results of the DG unit with proposed control scheme demonstrate good stability and performance robustness under the parameter uncertainty. Also, superior transient and steady‐state performance are confirmed over the conventional controller.
Online detection technology for SF6 decomposition products in electrical equipment: a review
Authors: Fan Xiaopeng , Li Li , Zhou Yongyan , Tang Nian , Zou Zhuanglei , Li Xiaodian , Huang Guojun , Liu Mingzheng
Published: April 2018

The decomposition component analysis method can be used to monitor and diagnose the insulation state of SF6 electrical equipment in power industry. Here, the authors firstly compared the advantages and disadvantages of various SF6 decomposition products detection methods and analysed their feasibility of online monitoring. Then the requirements of SF6 decomposition products online detecting technology according to the actual engineering needs were discussed. The SF6 decomposition products online detection system has been mainly introduced from the aspects of principle, structure, detection effect, and practicability. The research points and development tendency of SF6 decomposition products online detection system is forecasted.
VLTI/MIDI atlas of disks around low- and intermediate-mass young stellar objects
Authors: Varga J. , Ábrahám P. , Chen L. , Ratzka Th. , Gabányi K. É. , Kóspál Á. , Matter A. , van Boekel R. , Henning Th. , Jaffe W. , Juhász A. , Lopez B. , Menu J. , Moór A. , Mosoni L. , Sipos N.
Published: April 2018

Context. Protoplanetary disks show large diversity regarding their morphology and dust composition. With mid-infrared interferometry the thermal emission of disks can be spatially resolved, and the distribution and properties of the dust within can be studied.

Aims. Our aim is to perform a statistical analysis on a large sample of 82 disks around low- and intermediate-mass young stars, based on mid-infrared interferometric observations. We intend to study the distribution of disk sizes, variability, and the silicate dust mineralogy.

Methods. Archival mid-infrared interferometric data from the MIDI instrument on the Very Large Telescope Interferometer are homogeneously reduced and calibrated. Geometric disk models are used to fit the observations to get spatial information about the disks. An automatic spectral decomposition pipeline is applied to analyze the shape of the silicate feature.

Results. We present the resulting data products in the form of an atlas, containing N band correlated and total spectra, visibilities, and differential phases. The majority of our data can be well fitted with a continuous disk model, except for a few objects, where a gapped model gives a better match. From the mid-infrared size–luminosity relation we find that disks around T Tauri stars are generally colder and more extended with respect to the stellar luminosity than disks around Herbig Ae stars. We find that in the innermost part of the disks (r ≲ 1 au) the silicate feature is generally weaker than in the outer parts, suggesting that in the inner parts the dust is substantially more processed. We analyze stellar multiplicity and find that in two systems (AB Aur and HD 72106) data suggest a new companion or asymmetric inner disk structure. We make predictions for the observability of our objects with the upcoming Multi-AperTure mid-Infrared SpectroScopic Experiment (MATISSE) instrument, supporting the practical preparations of future MATISSE observations of T Tauri stars.
Pushing back the limits: detailed properties of dwarf galaxies in a ΛCDM universe
Authors: Revaz Yves , Jablonka Pascale
Published: April 2018

We present the results of a set of high-resolution chemo-dynamical simulations of dwarf galaxies in a ΛCDM cosmology. Out of an original (3.4 Mpc/h)3 cosmological box, a sample of 27 systems are re-simulated from z = 70 to z = 0 using a zoom-in technique. Gas and stellar properties are confronted to the observations in the greatest details: in addition to the galaxy global properties, we investigated the model galaxy velocity dispersion profiles, half-light radii, star formation histories, stellar metallicity distributions, and [Mg/Fe] abundance ratios. The formation and sustainability of the metallicity gradients and kinematically distinct stellar populations are also tackled. We show how the properties of six Local Group dwarf galaxies, NGC 6622, Andromeda II, Sculptor, Sextans, Ursa Minor and Draco are reproduced, and how they pertain to three main galaxy build-up modes. Our results indicate that the interaction with a massive central galaxy could be needed for a handful of Local Group dwarf spheroidal galaxies only, the vast majority of the systems and their variety of star formation histories arising naturally from a ΛCDM framework. We find that models fitting well the local Group dwarf galaxies are embedded in dark haloes of mass between 5 × 108 to a few 109 M⊙, without any missing satellite problem. We confirm the failure of the abundance matching approach at the mass scale of dwarf galaxies. Some of the observed faint however gas-rich galaxies with residual star formation, such as Leo T and Leo P, remain challenging. They point out the need of a better understanding of the UV-background heating.
Magnetic topology of the north solar pole
Authors: Pastor Yabar A. , Martínez González M. J. , Collados M.
Published: April 2018

The magnetism at the poles is similar to that of the quiet Sun in the sense that no active regions are present there. However, the polar quiet Sun is somewhat different from that at the activity belt as it has a global polarity that is clearly modulated by the solar cycle. We study the polar magnetism near an activity maximum when these regions change their polarity, from which it is expected that its magnetism should be less affected by the global field. To fully characterise the magnetic field vector, we use deep full Stokes polarimetric observations of the 15 648.5 and 15 652.8 Å FeI lines. We observe the north pole as well as a quiet region at disc centre to compare their field distributions. In order to calibrate the projection effects, we observe an additional quiet region at the east limb. We find that the two limb datasets share similar magnetic field vector distributions. This means that close to a maximum, the poles look like typical limb, quiet-Sun regions. However, the magnetic field distributions at the limbs are different from the distribution inferred at disc centre. At the limbs, we infer a new population of magnetic fields with relatively strong intensities (~600−800 G), inclined by ~30° with respect to the line of sight, and with an azimuth aligned with the solar disc radial direction. This line-of-sight orientation interpreted as a single magnetic field gives rise to non-vertical fields in the local reference frame and aligned towards disc centre. This peculiar topology is very unlikely for such strong fields according to theoretical considerations. We propose that this new population at the limbs is due to the observation of unresolved magnetic loops as seen close to the limb. These loops have typical granular sizes as measured in the disc centre. At the limbs, where the spatial resolution decreases, we observe them spatially unresolved, which explains the new population of magnetic fields that is inferred. This is the first (indirect) evidence of small-scale magnetic loops outside the disc centre and would imply that these small-scale structures are ubiquitous on the entire solar surface. This result has profound implications for the energetics not only of the photosphere, but also of the outer layers since these loops have been reported to reach the chromosphere and the low corona.
GaiaData Release 2
Authors: Soubiran C. , Jasniewicz G. , Chemin L. , Zurbach C. , Brouillet N. , Panuzzo P. , Sartoretti P. , Katz D. , Le Campion J.-F. , Marchal O. , Hestroffer D. , Thévenin F. , Crifo F. , Udry S. , Cropper M. , Seabroke G. , Viala Y. , Benson K. , Blomme R. , Jean-Antoine A. , Huckle H. , Smith M. , Baker S. G. , Damerdji Y. , Dolding C. , Frémat Y. , Gosset E. , Guerrier A. , Guy L. P. , Haigron R. , Janßen K. , Plum G. , Fabre C. , Lasne Y. , Pailler F. , Panem C. , Riclet F. , Royer F. , Tauran G. , Zwitter T. , Gueguen A. , Turon C.
Published: April 2018

Aims.The Radial Velocity Spectrometer (RVS) on board the ESA satellite missionGaiahas no calibration device. Therefore, the radial velocity zero point needs to be calibrated with stars that are proved to be stable at a level of 300 m s−1during theGaiaobservations.

Methods.We compiled a dataset of ~71 000 radial velocity measurements from five high-resolution spectrographs. A catalogue of 4813 stars was built by combining these individual measurements. The zero point was established using asteroids.

Results.The resulting catalogue has seven observations per star on average on a typical time baseline of 6 yr, with a median standard deviation of 15 m s−1. A subset of the most stable stars fulfilling the RVS requirements was used to establish the radial velocity zero point provided inGaiaData Release 2. The stars that were not used for calibration are used to validate the RVS data.
Closure behavior of spherical void in slab during hot rolling process
Authors: Cheng Rong , Zhang Jiongming , Wang Bo
Published: April 2018

The mechanical properties of steels are heavily deteriorated by voids. The influence of voids on the product quality should be eliminated through rolling processes. The study on the void closure during hot rolling processes is necessary. In present work, the closure behavior of voids at the center of a slab at 800 °C during hot rolling processes has been simulated with a 3D finite element model. The shape of the void and the plastic strain distribution of the slab are obtained by this model. The void decreases along the slab thickness direction and spreads along the rolling direction but hardly changes along the strip width direction. The relationship between closure behavior of voids and the plastic strain at the center of the slab is analyzed. The effects of rolling reduction, slab thickness and roller diameter on the closure behavior of voids are discussed. The larger reduction, thinner slab and larger roller diameter all improve the closure of voids during hot rolling processes. Experimental results of the closure behavior of a void in the slab during hot rolling process mostly agree with the simulation results..
Zentrum der Rehabilitation R. Geerlofs – Geht nicht gibt’s nicht
Authors: Dorschner-Geerlofs Daniela
Published: April 2018

Menschen, die ins Rehazentrum nach Pforzheim kommen, gelten oft als „austherapiert“. Die Therapeuten dort mögen es, herauszufinden, was sie bei einem Rehastillstand besser machen können. Eine große Herausforderung – die sie gerne annehmen.
Endoscopic ultrasound elastography of small solid pancreatic lesions: a multicenter study
Authors: Ignee Andre , Jenssen Christian , Arcidiacono Paolo G. , Hocke Michael , Möller Kathleen , Saftoiu Adrian , Will Uwe , Fusaroli Pietro , Iglesias-Garcia Julio , Ponnudurai Ryan , Petrone Maria C. , Braden Barbara , Burmester Eike , Dong Yi , Atkinson Nathan S. , Dietrich Christoph F.
Published: April 2018

Background The prevalence of malignancy in patients with small solid pancreatic lesions is low; however, early diagnosis is crucial for successful treatment of these cases. Therefore, a method to reliably distinguish between benign and malignant small solid pancreatic lesions would be highly desirable. We investigated the role of endoscopic ultrasound (EUS) elastography in this setting.

Methods Patients with solid pancreatic lesions ≤ 15 mm in size and a definite diagnosis were included. Lesion stiffness relative to the surrounding pancreatic parenchyma, as qualitatively assessed and documented at the time of EUS elastography, was retrospectively compared with the final diagnosis obtained by fine-needle aspiration/biopsy or surgical resection.

Results 218 patients were analyzed. The average size of the lesions was 11 ± 3 mm; 23 % were ductal adenocarcinoma, 52 % neuroendocrine tumors, 8 % metastases, and 17 % other entities; 66 % of the lesions were benign. On elastography, 50 % of lesions were stiffer than the surrounding pancreatic parenchyma (stiff lesions) and 50 % were less stiff or of similar stiffness (soft lesions). High stiffness of the lesion had a sensitivity of 84 % (95 % confidence interval 73 % – 91 %), specificity of 67 % (58 % – 74 %), positive predictive value (PPV) of 56 % (50 % – 62 %), and negative predictive value (NPV) of 89 % (83 % – 93 %) for the diagnosis of malignancy. For the diagnosis of pancreatic ductal adenocarcinoma, the sensitivity, specificity, PPV, and NPV were 96 % (87 % – 100 %), 64 % (56 % – 71 %), 45 % (40 % – 50 %), and 98 % (93 % – 100 %), respectively.

Conclusions In patients with small solid pancreatic lesions, EUS elastography can rule out malignancy with a high level of certainty if the lesion appears soft. A stiff lesion can be either benign or malignant.
Systematic review and meta-analysis of the effectiveness of radiofrequency ablation in low grade dysplastic Barrett’s esophagus
Authors: Pandey Gargi , Mulla Mubashir , Lewis Wyn , Foliaki Antonio , Chan David
Published: April 2018

Background Barrett’s esophagus (BE) is a premalignant condition characterized by replacement of the esophageal lining with metastatic columnar epithelium, and its management when complicated by low grade dysplasia (LGD) is controversial. This systematic review and meta-analysis aimed to determine the efficacy of radiofrequency ablation (RFA) in patients with LGD.

Methods MEDLINE, EMBASE, and Web of Science were searched for studies including patients with BE-associated LGD receiving RFA (January 1990 to May 2017). The outcome measures were complete eradication of intestinal metaplasia (CE-IM) and dysplasia (CE-D), rates of progression to high grade dysplasia (HGD) or cancer, and recurrence.

Results Eight studies including 619 patients with LGD (RFA = 404, surveillance = 215) were analyzed. After a median follow-up of 26 months (range 12 – 44 months), the overall pooled rates of CE-IM and CE-D after RFA were 88.17 % (95 % confidence interval [CI] 88.13 % – 88.20 %; P < 0.001) and 96.69 % (95 %CI 96.67 % – 96.71 %; P < 0.001), respectively. When compared with surveillance, RFA resulted in significantly lower rates of progression to HGD or cancer (odds ratio [OR] 0.07, 95 %CI 0.02 – 0.22). The pooled recurrence rates of IM and dysplasia were 5.6 % (95 %CI 5.57 – 5.63; P < 0.001) and 9.66 % (95 %CI 9.61 – 9.71; P < 0.001), respectively.

Conclusions RFA safely eradicates IM and dysplasia and reduces the rates of progression from LGD to HGD or cancer in the short term.
Nationaler Aktionsplan – Ideen zur Stärkung der Gesundheitskompetenz
Authors: Oldenburg Elke
Published: April 2018

Er umfasst 4 Handlungsfelder und gibt 15 Empfehlungen – der Nationale Aktionsplan Gesundheitskompetenz. Wertvolle Ideen, wie man die Gesundheitskompetenz fördern kann. Denn diese ist in Deutschland mangelhaft.
Three New Cytotoxic Monoterpenoid Bisindole Alkaloids from Tabernaemontana bufalina
Authors: Zhou Si-Yuan , Zhou Ting-Lan , Qiu Guofu , Huan Xiajuan , Miao Ze-Hong , Yang Sheng-Ping , Cao Shugeng , Fan Fengkai , Cai You-Sheng
Published: April 2018

Three new bisindole alkaloids, 3′-(2-oxopropyl)-19,20-dihydrotabernamine (1), 3′-(2-oxopropyl)-ervahanine B (2), 19,20-dihydrovobparicine (3), and 20 known compounds were isolated from the aerial parts of Tabernaemontana bufalina. The structures of these alkaloids were elucidated using spectroscopic methods. The absolute configurations of 1–3 were determined by the circular dichroic exciton chirality method. Compounds 1–23 were screened for their cytotoxicity against two human cancer cell lines, A-549 and MCF-7. Ten compounds (1–3, 10, 14, 16, 17, 19, 22, and 23) exhibited inhibitory effects against the two human cancer cells with IC50 values of 1.19 ~ 6.13 µM.
Enhanced Solubility and Permeability of Salicis cortex Extract by Formulating as a Microemulsion
Authors: Piazzini Vieri , Bigagli Elisabetta , Luceri Cristina , Bilia Anna Rita , Bergonzi Maria Camilla
Published: April 2018

A microemulsion system was developed and investigated as a novel oral formulation to increase the solubility and absorption of Salicis cortex extract. This extract possesses many pharmacological activities, in particular, it is beneficial for back pain and osteoarthritic and rheumatic complaints. In this work, after qualitative and quantitative characterization of the extract and the validation of an HPLC/diode array detector analytical method, solubility studies were performed to choose the best components for microemulsion formulation. The optimized microemulsion consisted of 2.5 g of triacetin, as the oil phase, 2.5 g of Tween 20 as the surfactant, 2.5 g of labrasol as the cosurfactant, and 5 g of water. The microemulsion was visually checked, characterized by light scattering techniques and morphological observations. The developed formulation appeared transparent, the droplet size was around 40 nm, and the ζ-potential result was negative. The maximum loading content of Salicis cortex extract resulted in 40 mg/mL. Furthermore, storage stability studies and an in vitro digestion assay were performed. The advantages offered by microemulsion were evaluated in vitro using artificial membranes and cells, i.e., parallel artificial membrane permeability assay and a Caco-2 model. Both studies proved that the microemulsion was successful in enhancing the permeation of extract compounds, so it could be useful to ameliorate the bioefficacy of Salicis cortex.
First TDAE Reactivity Using Benzonitrile Derivatives as Substrates and Its Application to the Synthesis of 3-Substituted Isochroman-1-ones
Authors: Khoumeri Omar , Terme Thierry , Vanelle Patrice
Published: April 2018

The first TDAE-initiated reaction between benzonitrile derivatives as substrates and substituted benzaldehydes to form substituted hydroxyethylbenzonitrile derivatives is reported. The 2-hydroxyethyl benzonitrile derivatives thus formed were good candidates for one-pot lactonization in a mixture of hydrochloric acid and methanol at 70 °C over five hours. These reactions furnished the corresponding 3-substituted isochroman-1-one derivatives in good yields.
An Improved Route for the Synthesis of Guanine Quadruplex Ligand Phen-DC3
Authors: Petitjean Anne , Miron Caitlin
Published: April 2018

The recognition of noncanonical DNA and RNA architectures such as guanine quadruplexes by small molecule ligands has become a promising strategy for anticancer and antiviral applications in recent years, leading to an exponential increase in the number of quadruplex ligands reported in the literature. There is consequently a need for ‘benchmark’ compounds which can be used as controls to facilitate comparisons between novel and previously reported ligands. One candidate for this role is Phen-DC3, which binds with high affinity and selectivity to guanine quadruplexes. To encourage its use in this role, an alternate synthetic route for the production of Phen-DC3 that may be more appropriate for implementation on a large scale is reported. This pathway eliminates the need for several hazardous reagents and increases the overall synthetic yield from 21% to a maximum of 43%.
Transition-Metal-Free С–С Coupling of 5,7-Dihydroxybenzopyrones with Quinoxalones and Pteridinones
Authors: Khalymbadzha Igor , Fatykhov Ramil , Chupakhin Oleg , Charushin Valery , Tseitler Tatiana , Sharapov Ainur , Inytina Anna , Kartsev Victor
Published: April 2018

A new synthetic protocol for nucleophilic substitution of hydrogen­ in quinoxalones and pteridinones by the action of 5,7-di­hydroxycoumarins and related m-dihydroxybenzene compounds has been developed. The C–C coupling reaction proved to proceed smoothly under rather mild conditions, thus giving the corresponding C–H functionalized products in good yields. The advantages of this environmentally benign protocol are high regio- and chemoselectivity, and an easy workup procedure. Direct incorporation of the coumarin moiety into the pyrazine ring in pteridines or quinoxalines provides a short pathway to pyrazine-coumarin hybrid compounds.
A Novel Method for the Chlorolactonization of Alkenoic Acids Using Diphenyl Sulfoxide/Oxalyl Chloride
Authors: Ding Rui , Lan Liyuan , Li Shuhui , Liu Yongguo , Yang Shaoxiang , Tian Hongyu , Sun Baoguo
Published: April 2018

A facile chlorolactonization of alkenoic acids by treatment with diphenyl sulfoxide/oxalyl chloride has been developed. The reaction can generate various chlorolactones in moderate to good yields, wherein the chlorodiphenylsufonium salt derived from diphenyl sulfoxide/oxalyl chloride serves as the source of Cl+.