bluuebunny/crossref_metadata_2025 huggingface dataset:
Safety and Optimization of Metabolic Labeling of Endothelial Progenitor Cells for Tracking
Authors: Han Sang-Soo , Shim Hye-Eun , Park Soon-Jung , Kim Byoung-Chul , Lee Dong-Eun , Chung Hyung-Min , Moon Sung-Hwan , Kang Sun-Woong
Published: August 2018

Metabolic labeling is one of the most powerful methods to label the live cell for in vitro and in vivo tracking. However, the cellular mechanisms by modified glycosylation due to metabolic agents are not fully understood. Therefore, metabolic labeling has not yet been widely used in EPC tracking and labeling. In this study, cell functional properties such as proliferation, migration and permeability and gene expression patterns of metabolic labeling agent-treated hUCB-EPCs were analyzed to demonstrate cellular effects of metabolic labeling agents. As the results, 10 μM Ac4ManNAz treatment had no effects on cellular function or gene regulations, however, higher concentration of Ac4ManNAz (>20 μM) led to the inhibition of functional properties (proliferation rate, viability and rate of endocytosis) and down-regulation of genes related to cell adhesion, PI3K/AKT, FGF and EGFR signaling pathways. Interestingly, the new blood vessel formation and angiogenic potential of hUCB-EPCs were not affected by Ac4ManNAz concentration. Based on our results, we suggest 10 μM as the optimal concentration of Ac4ManNAz for in vivo hUCB-EPC labeling and tracking. Additionally, we expect that our approach can be used for understanding the efficacy and safety of stem cell-based therapy in vivo.
Cochaperones enable Hsp70 to use ATP energy to stabilize native proteins out of the folding equilibrium
Authors: Xu Huafeng
Published: August 2018

The heat shock protein 70 (Hsp70) chaperones, vital to the proper folding of proteins inside cells, consume ATP and require cochaperones in assisting protein folding. It is unclear whether Hsp70 can utilize the free energy from ATP hydrolysis to fold a protein into a native state that is thermodynamically unstable in the chaperone-free equilibrium. Here I present a model of Hsp70-mediated protein folding, which predicts that Hsp70, as a result of differential stimulation of ATP hydrolysis by its Hsp40 cochaperone, dissociates faster from a substrate in fold-competent conformations than from one in misfolding-prone conformations, thus elevating the native concentration above and suppressing the misfolded concentration below their respective equilibrium values. Previous models would not make or imply these predictions, which are experimentally testable. My model quantitatively reproduces experimental refolding kinetics, predicts how modulations of the Hsp70/Hsp40 chaperone system affect protein folding, and suggests new approaches to regulating cellular protein quality.
Spin-wave interference in magnetic vortex stacks
Authors: Behncke Carolin , Adolff Christian F. , Lenzing Nicolas , Hänze Max , Schulte Benedikt , Weigand Markus , Schütz Gisela , Meier Guido
Published: August 2018

Spin waves with wavelengths in the nanometre range could serve as data carriers in future magnonic logic or signal processing devices. We investigate the interference of spin waves emitted from magnetic vortices in two exchange-coupled vortex stacks. The spin-wave dynamics are studied using scanning transmission X-ray microscopy and micromagnetic simulations. Stacks of vortices provide an excellent controllability of spin-wave properties including a tunable wavelength in the 100 nm regime and manipulation of their propagation direction via the magnetisation configuration. Furthermore, interference gives rise to amplified or reduced spin-wave amplitudes in distinct areas of the structure providing controlled confinement crucial for future applications of spin waves.
RBC deformability measurement based on variations of pressure in multiple micropillar channels during blood delivery using a disposable air-compressed pump
Authors: Kang Yang Jun
Published: August 2018

Cell-to-liquid interface as pressure sensor was suggested to detect RBC clogging in the micropillar channel under blood delivery using a disposable air-compressed pump.
Facile preparation of Ag nanoparticles using uric acid and their applications in colorimetric detection and catalysis
Authors: Dai Qijun , Wei Te , Lv Changli , Chai Fang
Published: August 2018

In this study, we have reported a facile, cost-effective method for the synthesis of silver nanoparticles (Ag NPs) using uric acid (UA) as the reducing agent.
Rational design of multi-stimuli-responsive gold nanorod–curcumin conjugates for chemo-photothermal synergistic cancer therapy
Authors: Zhu Falian , Tan Guozhu , Jiang Yaodong , Yu Zhiqiang , Ren Fei
Published: August 2018

The as-prepared Au NR@Curcumin exhibited significant contribution to chemo-photothermal synergistic cancer therapy.
Active targeted drug delivery of MMP-2 sensitive polymeric nanoparticles
Authors: Pan Jie , Li Pei-Jiao , Wang Yi , Chang Lu , Wan Dong , Wang Hao
Published: August 2018

MMP2-sensitive nanoparticles are developed with copolymers of TPGS3350-pp-PLGA and TPGS-folate in order to enhance the therapeutic efficiency of cancer.
Enantioselective synthesis of axially chiral vinyl arenes through palladium-catalyzed C–H olefination
Authors: Sun Qiao-Ying , Ma Wei-Yang , Yang Ke-Fang , Cao Jian , Zheng Zhan-Jiang , Xu Zheng , Cui Yu-Ming , Xu Li-Wen
Published: August 2018

A palladium-catalyzed ketoxime-chelation-assisted C–H olefination was developed to afford axially chiral vinyl arenes with excellent enantioselectivities.
Preparation of fibril nuclei of beta-amyloid peptides in reverse micelles
Authors: Lin Yen-Ling , Cheng Yu-Sheng , Ho Cheng-I , Guo Zhong-Hong , Huang Shing-Jong , Org Mai-Liis , Oss Andres , Samoson Ago , Chan Jerry Chun Chung
Published: August 2018

Protofibrils of beta-amyloid peptides formed by fibril nuclei incubated in reverse micelles.
Choline ionic liquid enhances the stability of Herceptin® (trastuzumab)
Authors: Reslan Mouhamad , Ranganathan Vijayaraghavan , Macfarlane Douglas R. , Kayser Veysel
Published: August 2018

Choline dihydrogen phosphate (CDHP) suppresses trastuzumab unfolding and early-stage aggregation
Hierarchically porous metal–organic frameworks with single-crystal structures and their enhanced catalytic properties
Authors: Zhang Hang , Huo Jinhao , Li Jinqing , Li Feier , Duan Chongxiong , Xi Hongxia
Published: August 2018

Stable hierarchically porous metal–organic frameworks (HP-MOFs) have been successfully synthesized under hydrothermal conditions using a template strategy.
Thermoelectrochemical cells based on Li+/Li redox couples in LiFSI glyme electrolytes
Authors: Kim Kyunggu , Lee Hochun
Published: August 2018

The interplay between the solvation structure of the electrolytes and the thermoelectrochemical performance was elucidated.
Atomically-defined model catalysts in ultrahigh vacuum and in liquid electrolytes: particle size-dependent CO adsorption on Pt nanoparticles on ordered Co3O4(111) films
Authors: Faisal Firas , Stumm Corinna , Bertram Manon , Wähler Tobias , Schuster Ralf , Xiang Feifei , Lytken Ole , Katsounaros Ioannis , Mayrhofer Karl J. J. , Schneider M. Alexander , Brummel Olaf , Libuda Jörg
Published: August 2018

We have studied particle size effects on atomically-defined model catalysts both in ultrahigh vacuum (UHV) and under electrochemical (EC) conditions in liquid electrolytes.
Performance of TDDFT with and without spin-flip in trajectory surface hopping dynamics: cis–trans azobenzene photoisomerization
Authors: Yue Ling , Liu Yajun , Zhu Chaoyuan
Published: August 2018

Quantum yields simulated by LR-TDDFT and SF-TDDFT methods for azobenzene photoisomerizations.
Mechanistic details of ethylene polymerization reaction using methallyl nickel(ii) catalysts
Authors: Ortega Daniela E. , Cortés-Arriagada Diego , Toro-Labbé Alejandro
Published: August 2018

We present a mechanistic study of the ligand functionalization of bulky boron co-activators on neutral methallyl Ni(ii) catalysts for polyethylene production. This provides a blueprint for the development and design of catalysts with a high degree of tunability in a more efficient way.
Effect of the triazole ring in zinc porphyrin-fullerene dyads on the charge transfer processes in NiO-based devices
Authors: Nikolaou Vasilis , Plass Fabian , Planchat Aurélien , Charisiadis Asterios , Charalambidis Georgios , Angaridis Panagiotis A. , Kahnt Axel , Odobel Fabrice , Coutsolelos Athanassios G.
Published: August 2018

Three covalently linked donor–acceptor zinc porphyrin–fullerene (ZnP–C60) dyads were tested as sensitizers in NiO-based dye-sensitized solar cells (DSCs).
Theoretical insight into joint photodynamic action of a gold(i) complex and a BODIPY chromophore for singlet oxygen generation
Authors: De Simone Bruna C. , Mazzone Gloria , Sang-aroon Wichien , Marino Tiziana , Russo Nino , Sicilia Emilia
Published: August 2018

Inclusion of a heavy gold atom in a peripheral position of BODIPY is enough to promote ISC.
Insight into the stereoselectivity of TS-1 in epoxidation ofcis/trans-2-hexene: a computational study
Authors: Li Mengzhao , Yan Xiaoyue , Zhu Meiyu , Wang Meiqi , Zhou Danhong
Published: August 2018

The mechanism of the stereoselectivity forcis/trans-2-hexene epoxidation in TS-1 zeolite was studied using density functional theory and the ONIOM scheme.
Computational investigation of LiF containing hypersalts
Authors: Price Chelsea , Winfough Matthew , Park Heejune , Meloni Giovanni
Published: August 2018

This study explores the design of possible hypersalts starting from the hyperhalogen Li3F4 plus a Li atom and the hyperalkali Li4F3 plus a F atom.
Design and synthesis of a family of 1D-lanthanide-coordination polymers showing luminescence and slow relaxation of the magnetization
Authors: Ruiz-Muelle Ana Belén , García-García Amalia , García-Valdivia Antonio A. , Oyarzabal Itziar , Cepeda Javier , Seco José M. , Colacio Enrique , Rodríguez-Diéguez Antonio , Fernández Ignacio
Published: August 2018

The synthesis and full characterization of a family of novel 1D-lanthanide-coordination polymers showing luminescence and SMM behavior is described.
A non-innocent pincer H3LONS ligand and its corresponding octahedral low-spin Fe(iii) complex formation via ligand-centric homolytic S–S bond scission
Authors: Sarkar Prasenjit , Mukherjee Chandan
Published: August 2018

Ligand-based S–S bond cleavage led to an unprecedented, homoleptic, six-coordinate, low-spin Fe(iii) complex comprising two 2-iminobenzosemiquinone and one thiyl π-radical.
Oriented external electric fields as mimics for probing the role of metal ions and ligands in the thermal gas-phase activation of methane
Authors: Geng Caiyun , Li Jilai , Schlangen Maria , Shaik Sason , Sun Xiaoyan , Wang Na , Weiske Thomas , Yue Lei , Zhou Shaodong , Schwarz Helmut
Published: August 2018

Unusual, if not unprecedented, effects of transition-metal ions and ligands are discovered when simple metal oxides or carbides activate methane in the gas phase in manners reminiscent of oriented external electric fields.
On the application of spectral corrections to particle flux measurements
Authors: Oosterwijk Aleid , Henzing Bas , Järvi Leena
Published: August 2018

An altered empirical method to estimate attenuation correction factors in particle flux measurements.
Environmentally friendly dyeing of cotton in an ethanol–water mixture with excellent exhaustion
Authors: Xia Liangjun , Wang Aming , Zhang Chunhua , Liu Yang , Guo Heng , Ding Cailing , Wang Yunli , Xu Weilin
Published: August 2018

Salt-free reactive dyeing with considerable reduction of water consumption was realized using a green ethanol–water mixture.
Na2S2O8-mediated efficient synthesis of isothiocyanates from primary amines in water
Authors: Fu Zhicheng , Yuan Wenhao , Chen Ning , Yang Zhanhui , Xu Jiaxi
Published: August 2018

Two procedures to synthesize isothiocyanates from primary amines are developed, with water as a solvent and sodium persulfate as an oxidant.
Development and application of human skeletal muscle microphysiological systems
Authors: Truskey George A.
Published: August 2018

Human microphysiological systems were developed to model skeletal muscle and nerve-skeletal muscle interactions. These systems can be applied to a number of major disease states involve skeletal muscle, including type 2 diabetes, muscular dystrophy, sarcopenia and cachexia arising from cancer or heart disease.
Silver nanowire/nickel hydroxide nanosheet composite for a transparent electrode and all-solid-state supercapacitor
Authors: Du Haojin , Pan Ying , Zhang Xiao , Cao Fuyang , Wan Tao , Du Haiwei , Joshi Rakesh , Chu Dewei
Published: August 2018

Silver nanowire (Ag NW) based composites have shown a great potential not just in transparent electrodes but in diverse functional applications.
Harnessing the unique properties of 2D materials for advanced lithium–sulfur batteries
Authors: Li Bin , Xu Hongfei , Ma Yang , Yang Shubin
Published: August 2018

Exploring application 2D materials to enhance the electrochemical performance of lithium–sulfur batteries became an important strategy in the past decade.
Highly efficient ZnO-based dye-sensitized solar cells with low-cost Co–Ni/carbon aerogel composites as counter electrodes
Authors: Cheng Jian , Ma Junhong , Ma Yuhua , Zhou Cui , Qiang Yue , Zhou Xiaofeng , Yang Jianya , Shi Haokun , Xie Yahong
Published: August 2018

Low-cost materials fabricated high-performance Co–Ni/carbon aerogels as counter electrodes.
Ultraviolet lasing in Zn-rich ZnO microspheres fabricated by laser ablation
Authors: Wang X. X. , Xu C. X. , Qin F. F. , Liu Y. J. , Manohari A. G. , You D. T. , Liu W. , Chen F. , Shi Z. L. , Cui Q. N.
Published: August 2018

ZnO/Zn microspheres were synthesized by an one-step laser ablation method, and the effect of surface plasmons induced an improved optical performance. Our work also demonstrated the physical process of Zn SPs resonant in the hybrid structure.
Epitaxial hard magnetic SmCo5 MFM tips – a new approach to advanced magnetic force microscopy imaging
Authors: Neu Volker , Vock Silvia , Sturm Tina , Schultz Ludwig
Published: August 2018

MFM tips nanofabricated from epitaxial SmCo5 films possess unprecedented magnetic hardness for improved performance in external fields and quantitative analysis.
Wireless piezoelectric devices based on electrospun PVDF/BaTiO3 NW nanocomposite fibers for human motion monitoring
Authors: Guo Wenzhe , Tan Cenxiao , Shi Kunming , Li Junwen , Wang Xiao-Xiong , Sun Bin , Huang Xingyi , Long Yun-Ze , Jiang Pingkai
Published: August 2018

Wireless piezoelectric devices based on electrospun PVDF/BaTiO3 NW nanocomposite fibers have been fabricated for human motion monitoring and analysis.
Optimizing the yield of A-polar GaAs nanowires to achieve defect-free zinc blende structure and enhanced optical functionality
Authors: Zamani Mahdi , Tütüncüoglu Gözde , Martí-Sánchez Sara , Francaviglia Luca , Güniat Lucas , Ghisalberti Lea , Potts Heidi , Friedl Martin , Markov Edoardo , Kim Wonjong , Leran Jean-Baptiste , Dubrovskii Vladimir G. , Arbiol Jordi , Fontcuberta i Morral Anna
Published: August 2018

Compound semiconductors exhibit an intrinsic polarity, as a consequence of the ionicity of their bonds.
Palladium-catalyzed cascade carboesterification of norbornene with alkynes
Authors: Wu Wanqing , Li Can , Li Jianxiao , Jiang Huanfeng
Published: August 2018

An efficient palladium-catalyzed cascade carboesterification has been achieved to afford functionalized α-methylene γ-lactone and tetrahydrofuran derivatives.
Copper-catalyzed C–N bond formation with imidazo[1,2-a]pyridines
Authors: Sun Kai , Mu Shiqiang , Liu Zhenhua , Feng Ranran , Li Yali , Pang Kui , Zhang Bing
Published: August 2018

An efficient Cu-catalyzed C–N bond formation with imidazo[1,2-a]pyridines on the C-3 position via a radical pathway is reported.
Enantioselective syntheses and application of 4-epi-galiellalactone and the corresponding activity-based probe: from strained bicycles to strained tricycles
Authors: Lu Yandong , Zhao Shan , Zhou Shijie , Chen Si-Cong , Luo Tuoping
Published: August 2018

Efficient syntheses of 4-epi-galiellalactone and the corresponding activity-based probe enabled chemoproteomic studies to reveal the biological targets.
Hybrid block copolymers of polyesters/polycarbonates and polypeptides synthesized via one-pot sequential ring-opening polymerization
Authors: Gradišar Špela , Žagar Ema , Pahovnik David
Published: August 2018

Polyester/polycarbonate-b-polypeptide hybrid block copolymers were synthesized by a sequential ring-opening polymerization in a one-pot manner.
Preparation and application of flavor and fragrance capsules
Authors: He Lei , Hu Jing , Deng Weijun
Published: August 2018

The preparation methods and applications of flavor and fragrance capsules based on polymeric, inorganic and polymeric–inorganic wall materials are summarized.
A flexible metal–organic framework with adaptive pores for high column-capacity gas chromatographic separation
Authors: He Chun-Ting , Ye Zi-Ming , Xu Yan-Tong , Xie Yi , Lian Xin-Lu , Zhang Jie-Peng , Chen Xiao-Ming
Published: August 2018

A new zinc pyrazolyl-carboxylate framework with multi-mode and adaptive flexibility has been synthesized for efficient gas chromatographic separations.
The influence of composition on the functionality of hybrid CuO–ZnO–Al2O3/HZSM-5 for the synthesis of DME from CO2 hydrogenation
Authors: Hu Yubing , Zhang Yajing , Du Jie , Li Chunyan , Wang Kangjun , Liu Lidong , Yu Xinrui , Wang Kai , Liu Nan
Published: August 2018

The introduction of Al2O3 increased the number of weak acid sites, altered the copper chemical state and improved the catalytic performance and stability consequently.
The kinetics process of a Pb(ii)/Pb(0) couple and selective fabrication of Li–Pb alloys in LiCl–KCl melts
Authors: Han Wei , Wang Wenjuan , Dong Yongchang , Li Mei , Yang Xiaoguang , Zhang Milin
Published: August 2018

Five Li–Pb intermetallic compounds are selectively prepared according to their deposition potentials and characterized by XRD and SEM.
Correction: Sustainable inverse-vulcanised sulfur polymers
Authors: Parker Douglas J. , Chong Samantha Y. , Hasell Tom
Published: August 2018

Correction for ‘Sustainable inverse-vulcanised sulfur polymers’ by Douglas J. Parker et al., RSC Adv., 2018, 8, 27892–27899.
A light-induced nitric oxide controllable release nano-platform based on diketopyrrolopyrrole derivatives for pH-responsive photodynamic/photothermal synergistic cancer therapy
Authors: Wang Ya , Huang Xiaoyu , Tang Yunyun , Zou Jianhua , Wang Peng , Zhang Yewei , Si Weili , Huang Wei , Dong Xiaochen
Published: August 2018

An intelligent multifunctional nano-platform responsive to the tumor microenvironment was established, which showed NO controllable “on–off” release and enhanced photodynamic/photothermal synergistic cancer therapy.
Visible-light-active g-C3N4/N-doped Sr2Nb2O7 heterojunctions as photocatalysts for the hydrogen evolution reaction
Authors: Adhikari Shiba P. , Hood Zachary D. , Chen Vincent W. , More Karren L. , Senevirathne Keerthi , Lachgar Abdou
Published: August 2018

Visible light active photocatalytic performance of g-C3N4/NSON-X heterojunctions.
Unconventional locomotion of liquid metal droplets driven by magnetic fields
Authors: Shu Jian , Tang Shi-Yang , Feng Zhihua , Li Weihua , Li Xiangpeng , Zhang Shiwu
Published: August 2018

We report an innovative method for controlling the locomotion of liquid metal droplets using Lorentz force induced by a magnetic field.
Flexibility of nanolayers and stacks: implications in the nanostructuration of clays
Authors: Honorio Tulio , Brochard Laurent , Vandamme Matthieu , Lebée Arthur
Published: August 2018

According to the flexibility of clays stacks and their hydration state, bending or shear regimes arise at the clay layer scale.
Post-synthetic modification of metal–organic frameworks for chiral gas chromatography
Authors: Kou Wen-Ting , Yang Cheng-Xiong , Yan Xiu-Ping
Published: August 2018

A post-synthetic modification strategy was established to synthesize a series of chiral metal–organic frameworks for gas chromatographic separation of diverse racemates.
Membrane and nucleus targeting for highly sensitive cancer cell detection using pyrophosphate and alkaline phosphatase activity-mediated fluorescence switching of functionalized carbon dots
Authors: Choi Cheong A , Mazrad Zihnil Adha Islamy , Ryu Ji Hyun , In Insik , Lee Kang Dae , Park Sung Young
Published: August 2018

Fluorescence-switching of Cu2+–CD for specific membrane and nucleus targeting based on PPi and ALP activity in tumor cells.
A shape-shifting composite hydrogel sheet with spatially patterned plasmonic nanoparticles
Authors: Guo Hongyu , Liu Yijing , Yang Yang , Wu Guangyu , Demella Kerry , Raghavan Srinivasa R. , Nie Zhihong
Published: August 2018

A simple and reliable approach was developed to fabricate thermo-responsive composite hydrogel sheets with spatially patterned regions of plasmonic gold nanoparticles. The same hydrogel exhibited different modes of shape deformation under near-infrared laser irradiation depending on the irradiation direction.
A light-emitting electrochemical cell (LEC) containing a hole-blocking layer of TmPyPB
Authors: Di Marcantonio Miriam , Vollkommer Frank , Bacher Gerd , Nannen Ekaterina
Published: August 2018

A hybrid LEC showing an efficiency improvement of almost a factor of 2 compared to the reference device was realized using a thin hole-blocking layer of TmPyPB.
Electronic, elastic and X-ray spectroscopic properties of direct and inverse full Heusler compounds Co2FeAl and Fe2CoAl, promising materials for spintronic applications: a DFT+Uapproach
Authors: Siakeng Lalrinkima , Mikhailov Gennady M. , Rai D. P.
Published: August 2018

Half-metallicity, low magnetic damping and high Curie temperatures (TC) are crucial for application in spintronics and full Heusler alloys are promising in this regard.
Microenvironments induced ring-closing of halide salts of oxazolidines: a rare inverse proton gradient process and its application in water-jet rewritable paper
Authors: Gao Wenbin , Qin Tianyou , Xi Guan , Sheng Lan , Zhang Sean Xiao-An
Published: August 2018

Ring-closing of ROF+X− generated biomimetic inverse proton gradient was successfully achieved via varying microenvironment for improved performance of water-jet rewritable paper.
High-performance photodetectors based on two-dimensional tin(ii) sulfide (SnS) nanoflakes
Authors: Liu Gangzha , Li Yan , Li Bo , Tian He , Fan Chao , Zhang Yonghui , Hua Zhongqiu , Wang Mengjun , Zheng Hongxing , Li Erping
Published: August 2018

A visible-light photodetector, based on two-dimensional SnS nanoflakes, exhibits an extremely high responsivity and detectivity with a fast response time.
An embryo-fetal development toxicity study with dimethylaminoethyl ginkgolide B in rats and rabbits
Authors: Li Ronghua , Zhang Tingting , Qin Mei , Yue Peng , Cai Ming , He Xuejun , Qiao Hongqun
Published: August 2018

The potential effects of dimethylaminoethyl ginkgolid B on pregnant dams and embryo-fetal development had been investigated in both Sprague-Dawley rats and New Zealand white rabbits.
Improved RIP‐based performance guarantee for sparse signal recovery via A*OMP
Authors: Li Haifeng , Liu Guoqi , Zou Jian
Published: August 2018

Combining the best‐first tree search and orthogonal matching pursuit (OMP), A*OMP has been introduced that aims at solving the compressed sensing problem. The theoretical analysis of A*OMP is mainly presented and an improved condition for exact recovery of sparse signals via the A*OMP algorithm is proposed.
Broadband heterogeneous terahertz frequency quantum cascade laser
Authors: Li L.H. , Garrasi K. , Kundu I. , Han Y.J. , Salih M. , Vitiello M.S. , Davies A.G. , Linfield E.H.
Published: August 2018

The authors demonstrate a broadband, heterogeneous terahertz frequency quantum cascade laser by exploiting an active region design based on longitudinal optical‐phonon‐assisted interminiband transitions. They obtain continuous wave laser emission with a threshold current density of ∼120 A/cm2, a dynamic range of ∼3.1, and an emission spectrum spanning from 2.4 to 3.4 THz at 15 K.
Gumbel copula based aggregated net load forecasting for modern power systems
Authors: Sreekumar Sreenu , Sharma Kailash Chand , Bhakar Rohit
Published: August 2018

Wind and solar have major share among the growing renewable penetration, due to their extensive availability and improved technologies. Both wind and solar generation are highly uncertain and intermittent as compared to system load. The increased number of such uncertain and intermittent variables necessitates complex multivariate operational strategies for system operation. A compilation of different uncertain and intermittent variables such as load, wind and solar generation, to a single uncertain variable called net load, reduces system operational planning complexity. Net load is the difference between total load and renewable generation. Thus, conventional generation units have to be scheduled for net load. Prior knowledge about net load can help optimum operational planning such as generation scheduling and power system flexibility estimations. There have been significant advancement in load and renewable generation forecasting over the last decades. Still, there is little attention towards net load forecasting (NLF). This study proposes a novel NLF model using Gumbel copula based joint probability distribution for load, wind and solar generation forecasting error aggregation. Gumbel copula covers all extreme forecasting errors due to max‐stable property. Proposed model uses modified Grey index models for forecasting. Results show that proposed model has strong potential in very short‐term NLF.
Detection of vehicle wheels from images using a pseudo‐wavelet filter for analysis of congested traffic
Authors: OBrien Eugene J. , Caprani Colin C. , Blacoe Serena , Guo Dong , Malekjafarian Abdollah
Published: August 2018

There is potential for significant savings if the safety of existing bridges can be more accurately assessed. For long‐span bridges, congestion is the governing traffic load condition. The current methods of simulating congestion make assumptions about the axle‐to‐axle gaps maintained between vehicles. There is potential for improvement in congestion models if accurate data on axle‐to‐axle gaps can be obtained. In this study, the use of a camera to collect this information is put forward. A new image processing technique is proposed to detect wheels in variable light conditions. The method is based on a pseudo‐wavelet filter that amplifies circles, in conjunction with an algorithm that weights features in the image according to their circularity. This new approach is compared with the Hough transform, template matching and the deformable part‐based model (DPM) methods previously developed. In a sample set of 80 images, 96.9% of wheels are detected, considerably more than with the Hough transform and template matching methods. It also provides the same level of accuracy as DPM without requiring a training process.
Improvement of global motion estimation in two‐dimensional digital video stabilisation methods
Authors: e Souza Marcos Roberto , da Fonseca Luiz Fernando Rodrigues , Pedrini Helio
Published: August 2018

A large amount of video content has been produced by compact and portable cameras. Several applications have been benefited from such growth of multimedia data, such as telemedicine, business conferencing, surveillance and security, entertainment, distance learning, and robotics. Video stabilisation is the process of detecting and removing undesired motion or instabilities from a video stream caused during the acquisition stage when handling the camera. In this work, the authors introduce and analyse a novel approach that identifies failures in the global motion estimation of the camera by means of local features. Moreover, they propose an optimisation method for computing a new estimate of the corrected motion. Experiments conducted on different video sequences are performed to demonstrate the effectiveness of the developed method. Results obtained with the stabilisation process are compared against the state‐of‐the‐art YouTube method.
Towards an efficient anomaly‐based intrusion detection for software‐defined networks
Authors: Latah Majd , Toker Levent
Published: August 2018

Software‐defined networking (SDN) is a new paradigm that allows developing more flexible network applications. A SDN controller, which represents a centralised controlling point, is responsible for running various network applications as well as maintaining different network services and functionalities. Choosing an efficient intrusion detection system helps in reducing the overhead of the running controller and creates a more secure network. In this study, we investigate the performance of the well‐known anomaly‐based intrusion detection approaches in terms of accuracy, false alarm rate, precision, recall, f1‐measure, area under receiver operator characteristic curve, execution time and McNemar's test. Precisely, the authors focus on supervised machine‐learning approaches where we use the following classifiers: decision trees, extreme learning machine, Naive Bayes, linear discriminant analysis, neural networks, support vector machines, random forest, K‐nearest‐neighbour, AdaBoost, RUSBoost, LogitBoost and BaggingTrees where we employ the well‐known NSL‐KDD benchmark dataset to compare the performance of each one of these classifiers.
Master–slave structure‐based capacitor voltage measuring technique for hybrid modular multilevel converters
Authors: Li Dongye , Sun Yichao , Zhang Shengqi , Ji Zhendong , Yue Yue , Zhao Jianfeng , You Jun
Published: August 2018

The measurement of the capacitor voltage of each sub‐module (SM) is a crucial part of achieving robust control of modular multilevel converters (MMCs). This study proposes a master–slave structure‐based capacitor voltage measuring technique (MS‐MT) for hybrid MMCs, in which the SM capacitor voltages are calculated using nine processes at the corresponding sampling instants according to the changing rule of the arm AC‐side voltage and SM operation states. In MS‐MT, the master sensor is used to measure the overall arm voltage while the slave sensor, which measures the full bridge, is used additionally to improve accuracy. Furthermore, MS‐MT performs well even under pre‐charging and DC short‐circuit fault conditions, for the reason that a single SM short‐circuit fault can be detected during above two conditions by comparing the voltages measured by the two sensors. Compared with the direct measuring technique, which has low measurement errors, and the overall measuring technique, which requires less hardware cost, MS‐MT inherits both advantages. Finally, extensive simulation and experimental results validate the effectiveness of the proposed MS‐MT.
Hybrid modulation method combining variable frequency and double phase‐shift for a 10 kW LLC resonant converter
Authors: Li Zhizhong , Wu Tianwen , Zhang Guidong , Yang Ru
Published: August 2018

Features of the wide input voltage, high efficiency, and high power density are eagerly required in electric vehicle charging pile applications (EVCPA). To realise these features, this study devises a novel variable frequency and double phase‐shift hybrid modulation method into the full‐bridge three‐level LLC resonant converter for EVCPA. Therein, this study deeply analyses the characteristics and conditions of soft switching in dual phase‐shift operations, and wide voltage gain range realisations under technique of variable frequency. A 10 kW/400 V/25 A prototype with 95.5% efficiency is built for verification, whose experimental results show that the proposed converter can well achieve the aforementioned features to further drive its wide applications.
Reliable simple method for suppression of leakage current in grid‐connected CHB inverters
Authors: Khalilzadeh Moghaddam Farhad , Iman‐Eini Hossein
Published: August 2018

In this study, a method for suppression of common‐mode current in the transformerless cascaded H‐bridge (CHB) photovoltaic inverter is proposed. The proposed approach reduces the leakage current in the transformerless 5‐level CHB inverters to a negligible value. By adding an ac switch to the structure of the CHB inverter, a new redundancy state for synthesising the zero voltage is obtained. Using this new redundancy state and available switching redundancies, the common‐mode voltage is kept constant and the leakage current is reduced. The performance of the proposed approach is compared with the already existing approach for reduction of leakage current, in the MATLAB/Simulink environment. Experimental investigations are also provided to verify the theoretical and simulation results.
Self‐stabilising hybrid connectivity control protocol for WSNs
Authors: Diédié Gokou Hervé Fabrice , Aka Boko , Babri Michel
Published: August 2018

In this study, the authors address the problem of combining hierarchical and flat techniques to construct and maintain nodes’ connectivity as well as links’ symmetry (bidirectionality) in a wireless sensor network (WSN) comprising static nodes. They propose a localised and asynchronous self‐stabilising hybrid message passing a solution that seamlessly merges three well known connectivity control techniques for such ad hoc networks, namely k ‐hop clustering , power control (transmission range adjustment) and sleep/wake scheduling. Their stigmergy‐based strategy (i.e. inspired from ants’ pheromone‐based communication, division of labour and swarming behaviours) allows a WSN to simultaneously cope with issues such as scalability, fault tolerance, transmission range minimisation, energy hole problem (i.e. premature node deaths in the vicinity of the sink), channel overhearing and signalisation reduction. To the best of their knowledge, such a solution does not exist in the literature. The few self‐stabilising hybrid connectivity control protocols currently proposed use only two of the above‐mentioned techniques. The authors formally prove the correctness of their scheme and its self‐stabilisation property under an unfair distributed daemon. Simulation results show that the proposed scheme has a low average convergence time, is energy efficient and can prolong network lifetime.
Low‐cost power gating solution to increase energy efficiency optimising duty cycling in wireless sensor nodes with power‐hungry sensors
Authors: Pinzi Michele , Pozzebon Alessandro
Published: August 2018

In this study, a solution focusing on energy efficiency of wireless sensor nodes is presented. Energy dissipation is a key factor affecting the usability of wireless sensor networks (WSNs) in that, in worst cases, in systems without electric mains, the life of a sensor node battery may last even only a few hours. The proposed solution is characterised by very low costs thanks to the use of a small number of electronic components: it allows the optimisation of duty cycling (i.e. the ratio between activity and inactivity periods of sensor nodes) by power gating the node (i.e. turning the whole circuitry off). In particular, this solution is useful for applications that use active power‐hungry sensors that are sampled regularly 10 to 1000 times a day. The described power control logic system is able to optimise the duty cycling, notably reducing the power consumption during idle periods, thus increasing the battery life at best up to 100–200 times: this means that the autonomous operation time of a WSN can increase from a few days to several months or even to some years according to the required sampling rate.
Physics‐based capacitance model of Gate‐on‐Source/Channel SOI TFET
Authors: Mitra Suman Kumar , Bhowmick Brinda
Published: August 2018

A surface potential‐based analytical capacitance model is proposed for gate‐on‐source–channel silicon on insulator (SOI) tunnel field effect transistor (GOSC TFET). The capacitance in the GOSC TFET is evidently shared by the gate‐to‐source capacitance which reduces the miller capacitance and leads to better switching speed in the circuit application. The effect of drain voltage, gate voltage, gate oxide thickness and source doping on the capacitance has been analysed in detail. The good matching between the modelled and Technology Computer‐Aided Design (TCAD) simulated surface potential leads to the accurate calculation of capacitance. The validation of the capacitance model is done by comparing the model result with the simulation result and a good agreement between them validates the model formulation.
Significant uncertainties from calibrating overshooting with eclipsing binary systems
Authors: Constantino Thomas , Baraffe Isabelle
Published: August 2018

The precise measurement of the masses and radii of stars in eclipsing binary systems provides a window into uncertain processes in stellar evolution, especially mixing at convective boundaries. Recently, these data have been used to calibrate models of convective overshooting in the cores of main sequence stars. In this study we have used a small representative sample of eclipsing binary stars with 1.25 ≤ M/M⊙ < 4.2 to test how precisely this method can constrain the overshooting and whether the data support a universal stellar mass–overshooting relation. We do not recover the previously reported stellar mass dependence for the extent of overshooting and in each case we find there is a substantial amount of uncertainty, that is, the same binary pair can be matched by models with different amounts of overshooting. Models with a moderate overshooting parameter 0.013 ≤ fos ≤ 0.014 (using the scheme from Herwig et al. 1997, A&A, 324, L81) are consistent with all eight systems studied. Generally, a much larger range of f is suitable for individual systems. In the case of main sequence and early post-main sequence stars, large changes in the amount of overshooting have little effect on the radius and effective temperature, and therefore the method is of extremely limited utility.
Solar meridional circulation from twenty-one years of SOHO/MDI and SDO/HMI observations
Authors: Liang Zhi-Chao , Gizon Laurent , Birch Aaron C. , Duvall Thomas L. , Rajaguru S. P.
Published: August 2018

Context. The solar meridional flow is an essential ingredient in flux-transport dynamo models. However, no consensus on its subsurface structure has been reached.

Aims. We merge the data sets from SOHO/MDI and SDO/HMI with the aim of achieving a greater precision on helioseismic measurements of the subsurface meridional flow.

Methods. The south-north travel-time differences are measured by applying time-distance helioseismology to the MDI and HMI medium-degree Dopplergrams covering May 1996–April 2017. Our data analysis corrects for several sources of systematic effects:P-angle error, surface magnetic field effects, and center-to-limb variations. For HMI data, we used theP-angle correction provided by the HMI team based on the Venus and Mercury transits. For MDI data, we used aP-angle correction estimated from the correlation of MDI and HMI data during the period of overlap. The center-to-limb effect is estimated from the east-west travel-time differences and is different for MDI and HMI observations. An interpretation of the travel-time measurements is obtained using a forward-modeling approach in the ray approximation.

Results. In the latitude range 20°–35°, the travel-time differences are similar in the southern hemisphere for cycles 23 and 24. However, they differ in the northern hemisphere between cycles 23 and 24. Except for cycle 24’s northern hemisphere, the measurements favor a single-cell meridional circulation model where the poleward flows persist down to ∼0.8R⊙, accompanied by local inflows toward the activity belts in the near-surface layers. Cycle 24’s northern hemisphere is anomalous: travel-time differences are significantly smaller when travel distances are greater than 20°. This asymmetry between northern and southern hemispheres during cycle 24 was not present in previous measurements, which assumed a differentP-angle error correction where south-north travel-time differences are shifted to zero at the equator for all travel distances. In our measurements, the travel-time differences at the equator are zero for travel distances less than ∼30°, but they do not vanish for larger travel distances. This equatorial offset for large travel distances need not be interpreted as a deep cross-equator flow; it could be due to the presence of asymmetrical local flows at the surface near the end points of the acoustic ray paths.

Conclusions. The combined MDI and HMI helioseismic measurements presented here contain a wealth of information about the subsurface structure and the temporal evolution of the meridional circulation over 21 years. To infer the deep meridional flow, it will be necessary to model the contribution from the complex time-varying flows in the near-surface layers.
Alzheimer’s disease as a metabolic disorder
Authors: Bloom George S. , Norambuena Andrés
Published: August 2018

Alzheimer’s disease (AD) is defined by memory loss and cognitive impairment, along with the accumulation in brain of two types of abnormal structures, extracellular amyloid plaques and intraneuronal neurofibrillary tangles. Both plaques and tangles are composed predominantly of poorly soluble filaments that respectively assemble from amyloid-β (Aβ) peptides and the neuron-specific, microtubule-associated protein, tau. It is now widely acknowledged that soluble oligomers of Aβ and tau, the building blocks of plaques and tangles, are principal drivers of AD pathogenesis by acting coordinately to impair and destroy synapses, and kill neurons. The behavioral features of AD are a direct consequence of these attacks on synapses and neuronal viability, which in turn reflect a reduced capacity of AD neurons to utilize energy sources needed to maintain neuronal function and vitality. In other words, AD neurons are starving, even when they may be surrounded by abundant nutrients. Here, we review some of the evidence for the metabolic deficiencies of neurons in AD and how they impact neuronal health.
Die Veränderung des sagittalen Profils im Alter und dessen therapeutische Relevanz
Authors: Tschöke Sven
Published: August 2018

Die steigende Zahl der komplexen Wirbelsäulendeformitäten im Alter stellt eine neue therapeutische Herausforderung dar. Hierbei wird dem komplexen Zusammenspiel der spinopelvinen Kompensationsmechanismen eine besondere Bedeutung zugeschrieben. Obwohl die Analyse der globalen sagittalen Balance wesentlich zum Verständnis dieser Mechanismen beigetragen hat, wird die vereinfachte algebraische Darstellung und Definition des „normalen“ Sagittalprofils dem älteren Patienten mit multiplen degenerativen Veränderungen des Bewegungsapparates nicht gerecht. Vielmehr ist beim älteren Patienten eine durch die unzureichende Flexibilität der benachbarten Strukturen limitierte „Komfort-Balance“ funktionell nicht zwingend nachteilig. Dennoch sollte das therapeutische Ziel immer die Wiederherstellung einer harmonischen Lastverteilung an der Wirbelsäule sein. Bei älteren Patienten mit einer symptomatisch dekompensierten sagittalen Imbalance, bleibt die rein konservative Therapie meist ohne Erfolg. In diesen Fällen sollte immer die strukturell zugrunde liegende Pathologie im Sinne der Profilkorrektur adressiert werden. Die Wahl der operativen Technik, Länge des Konstrukts und dessen Verankerungspunkte müssen dabei die individuellen Möglichkeiten, Risiken und Bedürfnisse des älteren Patienten berücksichtigen, um eine iatrogene Invalidisierung und komplikationsbedingte Sekundäreingriffe zu vermeiden. Mit stetig steigender Lebenserwartung unserer Bevölkerung werden wir uns dem wachsenden Anspruch, auch im hohen Alter aktiv bleiben zu können, stellen müssen. Dies setzt ein ganzheitliches Verständnis der patienteneigenen Leistungsfähigkeit sowie eine realistische Einschätzung des zu erzielenden Ergebnisses und das Beherrschen aller operativer Korrekturtechniken voraus.
Effects of two instrument-generation changes on adenoma detection rate during screening colonoscopy: results from a prospective randomized comparative study
Authors: Zimmermann-Fraedrich Katharina , Groth Stefan , Sehner Susanne , Schubert Stefan , Aschenbeck Jens , Mayr Michael , Aminalai Alireza , Schröder Andreas , Bruhn Jens-Peter , Bläker Michael , Rösch Thomas , Schachschal Guido
Published: August 2018

Background Previous studies have shown that multiple colonoscope features have to be changed before an improvement in adenoma detection rate (ADR) becomes obvious, such as with changing from one instrument generation to the next but one. We wanted to evaluate whether such an effect can also be observed in a private-practice screening setting.

Methods In a randomized study, we compared the latest generation colonoscopes from one company (Olympus Exera III, 190) with the next to last one (Olympus 165), including only patients presenting for screening colonoscopy. The primary outcome was ADR achieved with 190 colonoscopes (190-C) in comparison with 165 colonoscopes (165-C).

Results 1221 patients (46.1 % men; mean age 62.2 years, standard deviation 6.6) were included (599 screened with the Olympus Exera III, 190). The ADR difference in favor of the 190-C instrument (32 % [95 % confidence interval (CI) 26 % to 39 %] vs. 28 % [95 %CI 22 % to 34 %] in the 165-C group) failed to reach statistical significance (P = 0.10); only the rate of small (< 5 mm) adenomas was significantly increased at 22.5 % (95 %CI 19 % to 26 %) vs. 15.6 % (95 %CI 13 % to 18 %; P = 0.002). Furthermore, significantly more adenomas were found in the 190-C group, with an adenoma rate (all adenomas/all patients) of 0.57 (95 %CI 0.53 to 0.61) vs. 0.47 (95 %CI 0.43 to 0.51; P < 0.001).

Conclusions This randomized comparative trial in a private-practice screening setting only partially confirmed the results of prior studies that, with multiple imaging improvements achieved over two instrument generations, an increase in overall adenoma number becomes measurable.
Fully vs. partially covered selfexpandable metal stent for palliation of malignant esophageal strictures: a randomized trial (the COPAC study)
Authors: Didden Paul , Reijm Agnes , Erler Nicole , Wolters Leonieke , Tang Thjon , ter Borg Pieter , Leeuwenburgh Ivonne , Bruno Marco , Spaander Manon
Published: August 2018

Background Covered esophageal self-expandable metal stents (SEMSs) are currently used for palliation of malignant dysphagia. The optimal extent of the covering to prevent recurrent obstruction is unknown. Therefore, we aimed to compare fully covered (FC) versus partially covered (PC) SEMSs in patients with incurable malignant esophageal stenosis.

Methods In this multicenter randomized controlled trial, 98 incurable patients with dysphagia caused by a malignant stricture of the esophagus or cardia were randomized 1:1 to an FC-SEMS or PC-SEMS. The primary outcome was recurrent obstruction after endoscopic SEMS placement. Secondary outcomes were technical and clinical success, adverse events, and health-related quality of life (HRQoL). Patients were followed until 6 months after SEMS placement or to SEMS removal, second SEMS insertion, or death, whichever came first.

Results Recurrent obstruction after SEMS placement was similar for both types of stents: 19 % for FC-SEMSs and 22 % for PC-SEMSs (P = 0.65). The times to recurrent obstruction did not differ. The frequency of adverse events was similar between the two groups, with major adverse events occurring in 38 % and 47 % of patients for FC-SEMSs and PC-SEMSs, respectively (P = 0.34). No significant differences were seen in technical success, improvement of dysphagia, and HRQoL. Proximal esophageal stenosis and female sex were independently associated with recurrent obstruction and/or major adverse events.

Conclusions Esophageal FC-SEMSs did not reveal a lower recurrent obstruction rate compared with PC-SEMSs in the palliative management of malignant dysphagia.