bluuebunny/crossref_metadata_2025 huggingface dataset:
Simultaneous production and functionalization of hexagonal boron nitride nanosheets by solvent-free mechanical exfoliation for superlubricant water-based lubricant additives
Authors: An Lulu , Yu Yuanlie , Bai Changning , Bai Yongqing , Zhang Bin , Gao Kaixiong , Wang Xinbo , Lai Zhiping , Zhang Junyan
Published: July 2019

Hexagonal boron nitride nanosheets (h-BNNSs), with a crystal lattice structure similar to graphene by over 98%, exhibit good lubrication properties as lubricant additives. However, the poor dispersibility in solvents has limited their wide practical applications as lubricant additives. In the present report, water dispersible Pebax functionalized h-BNNSs (Pebax-BNNSs) have been prepared through a one-step solvent-free mechanical exfoliation process which relies on a simple exfoliation of h-BN layers by shearing force in molten Pebax at 200 °C. In this process, Pebax molecules can synchronously react with the dangling bonds formed during the exfoliation process to achieve in situ functionalization of h-BNNSs. The reciprocating friction tests demonstrate that the as-obtained Pebax-BNNSs possess excellent antifriction and antiwear performance as water-based lubricant additive with a low concentration of 0.3 mg/mL under atmospheric condition. The friction coefficients can be <0.01, achieving superlubrication. Further systematical investigations on the wear traces, wear debris, and counter balls propose a “dispersion-compensation-filling repairment” friction mechanism. All these results demonstrate that h-BNNSs can achieve superlubrication as water-based lubricant additives via facile surface modification, making them very promising candidates as lubricant additives in practical applications.
Multi-omic analysis in transgenic mice implicates omega-6/omega-3 fatty acid imbalance as a risk factor for chronic disease
Authors: Kaliannan Kanakaraju , Li Xiang-Yong , Wang Bin , Pan Qian , Chen Chih-Yu , Hao Lei , Xie Shanfu , Kang Jing X.
Published: July 2019

An unbalanced increase in dietary omega-6 (n-6) polyunsaturated fatty acids (PUFA) and decrease in omega-3 (n-3) PUFA in the Western diet coincides with the global rise in chronic diseases. Whether n-6 and n-3 PUFA oppositely contribute to the development of chronic disease remains controversial. By using transgenic mice capable of synthesizing PUFA to eliminate confounding factors of diet, we show here that alteration of the tissue n-6/n-3 PUFA ratio leads to correlated changes in the gut microbiome and fecal and serum metabolites. Transgenic mice able to overproduce n-6 PUFA and achieve a high tissue n-6/n-3 PUFA ratio exhibit an increased risk for metabolic diseases and cancer, whereas mice able to convert n-6 to n-3 PUFA, and that have a lower n-6/n-3 ratio, show healthy phenotypes. Our study demonstrates that n-6 PUFA may be harmful in excess and suggests the importance of a low tissue n-6/n-3 ratio in reducing the risk for chronic diseases.
Transient heat release during induced mitochondrial proton uncoupling
Authors: Rajagopal Manjunath C. , Brown Jeffrey W. , Gelda Dhruv , Valavala Krishna V. , Wang Huan , Llano Daniel A. , Gillette Rhanor , Sinha Sanjiv
Published: July 2019

Non-shivering thermogenesis through mitochondrial proton uncoupling is one of the dominant thermoregulatory mechanisms crucial for normal cellular functions. The metabolic pathway for intracellular temperature rise has widely been considered as steady-state substrate oxidation. Here, we show that a transient proton motive force (pmf) dissipation is more dominant than steady-state substrate oxidation in stimulated thermogenesis. Using transient intracellular thermometry during stimulated proton uncoupling in neurons ofAplysia californica, we observe temperature spikes of ~7.5 K that decay over two time scales: a rapid decay of ~4.8 K over ~1 s followed by a slower decay over ~17 s. The rapid decay correlates well in time with transient electrical heating from proton transport across the mitochondrial inner membrane. Beyond ~33 s, we do not observe any heating from intracellular sources, including substrate oxidation and pmf dissipation. Our measurements demonstrate the utility of transient thermometry in better understanding the thermochemistry of mitochondrial metabolism.
Metal-organic framework functionalization and design strategies for advanced electrochemical energy storage devices
Authors: Baumann Avery E. , Burns David A. , Liu Bingqian , Thoi V. Sara
Published: July 2019

Metal-organic frameworks (MOFs) are a class of porous materials with unprecedented chemical and structural tunability. Their synthetic versatility, long-range order, and rich host–guest chemistry make MOFs ideal platforms for identifying design features for advanced functional materials. This review addresses synthetic approaches to control MOF attributes for realizing material properties such as charge conductivity, stability, surface area, and flexibility. Along with an updated account on MOFs employed in batteries and supercapacitors, new directions are outlined for advancing MOF research in emergent technologies such as solid-state electrolytes and battery operation in extreme environments.
Monitoring of nine pesticides in different cereal flour samples with high performance liquid chromatography-diode array detection
Authors: Abbaspour Maryam , Farajzadeh Mir Ali , Sorouraddin Saeed Mohammad , Mohebbi Ali
Published: July 2019

A method based on LLLE-DLLME-HPLC-DAD has been developed for the extraction and determination of nine multiclass pesticides from selected cereals.
The bioconjugation of DNA with gold nanoparticles towards the spectrophotometric genosensing of pathogenic bacteria
Authors: Mobed Ahmad , Hasanzadeh Mohammad , Aghazadeh Mohammad , Saadati Arezoo , Hassanpour Soodabeh , Mokhtarzadeh Ahad
Published: July 2019

The investigation of important bio-molecular events such as expression of special genes has shown promise with the advent of nanotechnology.
Core@shell nanostructured Au-d@NimPtm for electrochemical oxygen reduction reaction: effect of the core size and shell thickness
Authors: Zhang Min , Miao Shu , Xu Bo-Qing
Published: July 2019

Au-d@NimPtm nanostructures are studied to address the effects of the Au-core size (d) and NiPt-shell thickness (m) on the electrocatalytic performance of Pt for the ORR.
Conditions for stable operation of solid oxide electrolysis cells: oxygen electrode effects
Authors: Park Beom-Kyeong , Zhang Qian , Voorhees Peter W. , Barnett Scott A.
Published: July 2019

The fracture at the electrode/electrolyte interface occurs for a critical oxygen pressure and an associated electrode overpotential.
Do graphene oxide nanostructured coatings mitigate bacterial adhesion?
Authors: Wuolo-Journey Karl , BinAhmed Sara , Linna Elise , Romero-Vargas Castrillón Santiago
Published: July 2019

Graphene oxide (GO) is a biocidal nanomaterial, but is it also anti-adhesive? Here we show that GO-based coatings exhibiting low bacterial adhesion properties can be formed by edge-tethering GO nanosheets to hydrophilic polymer brushes.
Oxidation of ammonium by FeammoxAcidimicrobiaceaesp. A6 in anaerobic microbial electrolysis cells
Authors: Ruiz-Urigüen Melany , Steingart Daniel , Jaffé Peter R.
Published: July 2019

Schematic of a biotic MEC with Feammox bacteriumAcidimicrobiaceaesp. A6 culture. NH4+is oxidized to NO2−at the anode and H+is reduced to form H2at the cathode.
Antidiabetic activity of a polysaccharide-protein complex from Asian Clam (Corbicula fluminea) in streptozotoxin-induced diabetic rats and its underlying mechanism
Authors: Wang Yao-Yao , Zhu Jie , Ma Haile , Ding Zhi-Chao , Li Lin , Yan Jing-Kun
Published: July 2019

Antidiabetic activity of a polysaccharide-protein complex from Asian Clam (Corbicula fluminea) in streptozotoxin-induced diabetic rats and its underlying mechanism.
Challenges of traditional herbal teas: plant infusions and their mixtures with bioactive properties
Authors: Caleja Cristina , Finimundy Tiane C. , Pereira Carla , Barros Lillian , Calhelha Ricardo C. , Sokovic Marina , Ivanov Marija , Carvalho Ana Maria , Rosa Eduardo , Ferreira Isabel C. F. R.
Published: July 2019

Five traditional and medicinal plants have been individually characterized and analyzed in terms of bioactivities to determine how these characteristics are modified when preparing blends.
Ammonia photosynthesis via an association pathway using a plasmonic photoanode and a zirconium cathode
Authors: Oshikiri Tomoya , Ueno Kosei , Misawa Hiroaki
Published: July 2019

Ammonia photosynthesis under visible light irradiation via an associative pathway using a plasmonic photoanode and a zirconium cathode is proposed.
Glycans in drug discovery
Authors: Valverde Pablo , Ardá Ana , Reichardt Niels-Christian , Jiménez-Barbero Jesús , Gimeno Ana
Published: July 2019

Exploiting glycan recognition in drug discovery.
Growth of 2H stacked WSe2 bilayers on sapphire
Authors: Han Ali , Aljarb Areej , Liu Sheng , Li Peng , Ma Chun , Xue Fei , Lopatin Sergei , Yang Chih-Wen , Huang Jing-Kai , Wan Yi , Zhang Xixiang , Xiong Qihua , Huang Kuo-Wei , Tung Vincent , Anthopoulos Thomas D. , Li Lain-Jong
Published: July 2019

Bilayer WSe2 nuclei were initially grown along the atomic steps of a sapphire substrate, resembling a “graphoepitaxial mechanism” and gradually formed into overlapped 2H stacked WSe2 bilayers.
Advances in the regulation of bipyridine derivatives on two-dimensional (2D) supramolecular nanostructures
Authors: Li Xiaokang , Zhang Siqi , Li Jianqiao , Qian Yuxin , Duan Wubiao , Zeng Qingdao
Published: July 2019

In this review, we discuss a series of two-dimensional (2D) supramolecular nanostructures prepared on highly oriented pyrolytic graphite (HOPG) by STM.
Intramolecular hydrogen bond directed distribution of conformational populations in the derivatives ofN′-benzylidenebenzohydrazide
Authors: Arya Neeru , Mishra Sandeep Kumar , Suryaprakash N.
Published: July 2019

The extensive NMR investigations reveal the presence ofE-isomers in the derivative ofN′-benzylidenebenzohydrazide. The different conformer populations are controlled by the strength of intramolecular hydrogen bonds.
Synthesis of (V2/3Sc1/3)2AlC i-MAX phase and V2−xC MXene scrolls
Authors: Thörnberg Jimmy , Halim Joseph , Lu Jun , Meshkian Rahele , Palisaitis Justinas , Hultman Lars , Persson Per O.Å. , Rosen Johanna
Published: July 2019

We report the synthesis and characterization of a new laminated i-MAX phase, (V2/3Sc1/3)2AlC, with in-plane chemical ordering between the M-elements. We also produce V2−xC MXene with only 24 h etching time using HF and MXene scrolls using LiF + HCl.
DNA nanostructures from double-C-shaped motifs with controllable twist and curvature
Authors: Yang Donglei , Huang Kai , Wang Pengfei , Mi Yongli , Wei Bryan
Published: July 2019

We demonstrate twist and curvature engineering in DNA nanostructures from the scaffold-free approach.
Ultrasoft silicon nanomembranes: thickness-dependent effective elastic modulus
Authors: Katiyar Ajit K. , Davidson Ashwini Ann , Jang Houk , Hwangbo Yun , Han Byeori , Lee Seonwoo , Hagiwara Yohei , Shimada Takahiro , Hirakata Hiroyuki , Kitamura Takayuki , Ahn Jong-Hyun
Published: July 2019

The mechanical properties of ultrathin Si nanomembranes having thicknesses of 2 to 35 nm have been investigated by determining biaxial Young's modulus. The nanomembrane sample with thickness of 2 nm showed very low modulus value of 3.25 GPa.
Norbornadiene–dihydroazulene conjugates
Authors: Kilde Martin Drøhse , Mansø Mads , Ree Nicolai , Petersen Anne Ugleholdt , Moth-Poulsen Kasper , Mikkelsen Kurt V. , Nielsen Mogens Brøndsted
Published: July 2019

Conjugates of norbornadiene (NBD) and dihydroazulene (DHA) photoswitches were synthesised and subjected to isomerisation studies.
Extraction of DNA from complex biological sample matrices using guanidinium ionic liquid modified magnetic nanocomposites
Authors: Liu Mei , Ding Xueqin , Wang Xuelian , Li Jianzhong , Yang Huansheng , Yin Yulong
Published: July 2019

The DNA extracted from biological samples by using the GIL-MCGO nanocomposites are well suitable for PCR amplifications.
Controlling the nucleophilic properties of cobalt salen complexes for carbon dioxide capture
Authors: Chiong Meliton R. , Paraan Francis N. C.
Published: July 2019

The nucleophilic properties of cobalt salen complexes are examined using density functional theory to investigate its carbon fixing capacity.
Targeted neurotransmitter metabolomics profiling of oleanolic acid in the treatment of spontaneously hypertensive rats
Authors: Yu Ruixue , Yang Wenqing , Qi Dongmei , Gong Lili , Li Chao , Li Yunlun , Jiang Haiqiang
Published: July 2019

Essential hypertension (EH) is a prevalent chronic medical condition and a major risk factor for cardiovascular morbidity and mortality.
Study on enhancing sludge methanogenesis by adding acetylene black and effect on the characteristics & microbial community of anaerobic granular sludge
Authors: Ma Haitong , Wu Ming , Liu Hui , Wang Zhiwei , Guo Chenyan , Wang Shuangfei
Published: July 2019

Illustration of the interspecies electron transfer improved by ACET during methanogenesis.
Magnetically retrievable Ce-doped Fe3O4 nanoparticles as scaffolds for the removal of azo dyes
Authors: Aashima Aashima , Uppal Shivani , Arora Arushi , Gautam Sanjeev , Singh Suman , Choudhary R. J. , Mehta S. K.
Published: July 2019

Considering the significant impact of magnetically retrievable nanostructures, herein, Ce-doped Fe3O4 nanoparticles were employed as scaffolds for the removal of the Reactive Black 5 (RB5), an azo dye.
Protective effects of macamides fromLepidium meyeniiWalp. against corticosterone-induced neurotoxicity in PC12 cells
Authors: Yu Zejun , Jin Wenwen , Cui Yajie , Ao Mingzhang , Liu Hao , Xu Hang , Yu Longjiang
Published: July 2019

Neuroprotection of macamides is probably associated with inhibition of the mitochondrial apoptotic and the activation of the phosphorylation of Akt and CREB.
Role of polysilicon in poly-Si/SiOxpassivating contacts for high-efficiency silicon solar cells
Authors: Park HyunJung , Bae Soohyun , Park Se Jin , Hyun Ji Yeon , Lee Chang Hyun , Choi Dongjin , Kang Dongkyun , Han Hyebin , Kang Yoonmook , Lee Hae-Seok , Kim Donghwan
Published: July 2019

The efficiency of silicon solar cell with poly-Si/SiOxpassivating contact was improved by etching of poly-Si which improves short circuit current density without affecting passivation quality and fill factor.
Biowaste-derived 3D honeycomb-like N and S dual-doped hierarchically porous carbons for high-efficient CO2 capture
Authors: Shi Weiwei , Wang Rongzhen , Liu Huili , Chang Binbin , Yang Baocheng , Zhang Zuling
Published: July 2019

We proposed a facile and cost-effective strategy to prepare N/S dual-doped carbons with abundant micropores of <1 nm, appropriate proportion of meso/macropores and suitable surface functionalization for highly efficient CO2 capture.
Surfactant-free synthesis of porous Au by a urea complex
Authors: Zhang Qiang , Zang Biao , Wang Shaozhen
Published: July 2019

A gold–urea complex was incinerated to transform into porous hollow gold nanoparticles (PHAuNPs), and the PHAuNPs present high catalytic activity.
Recent synthetic advances in pyridine-based thermotropic mesogens
Authors: Devadiga Deepak , Ahipa T. N.
Published: July 2019

Currently, numerous articles have reported pyridine-based thermotropic mesogens; however, reviews of their synthetic methodologies are rare.
Metal-free perovskites for non linear optical materials
Authors: Kasel Thomas W. , Deng Zeyu , Mroz Austin M. , Hendon Christopher H. , Butler Keith T. , Canepa Pieremanuele
Published: July 2019

We identify the existence of nonlinear optical (NLO) activity in a number of novel ABX3-type metal-free perovskites, where A is a highly tuneable organic cation, B is a NH4 cation and X is a halide anion.
Commercially available InSb as a high-performance anode for secondary batteries towards superior lithium storage
Authors: Li Wenying , Liu Tingting , Zhang Jundong , Peng Na , Zheng Runtian , Yu Haoxiang , Bai Ying , Cui Yanhua , Shu Jie
Published: July 2019

This paper reports the possible application of commercially available InSb alloys as an appealing anode host for lithium storage.
Ionic mesoporous polyamides enable highly dispersed ultrafine Ru nanoparticles: a synergistic stabilization effect and remarkable efficiency in levulinic acid conversion into γ-valerolactone
Authors: Wang Qian , Ling Xingchen , Ye Tingting , Zhou Yu , Wang Jun
Published: July 2019

Ionic mesoporous polyamides led to highly dispersed ultrafine Ru nanoparticles for the efficient conversion of levulinic acid into γ-valerolactone.
Two-dimensional lead-free iodide-based hybrid double perovskites: crystal growth, thin-film preparation and photocurrent responses
Authors: Bi Le-Yu , Hu Yue-Qiao , Li Mu-Qing , Hu Tian-Li , Zhang Hao-Lan , Yin Xing-Tian , Que Wen-Xiu , Lassoued Mohamed Saber , Zheng Yan-Zhen
Published: July 2019

Herein, lead-free layered iodide double perovskites (C6H16N2)2MBiI8 (M = Ag/Cu) were synthesized, which showed typical semiconducting properties and obvious photocurrent response.
Ca2+-doped ultrathin cobalt hydroxyl oxides derived from coordination polymers as efficient electrocatalysts for the oxidation of water
Authors: Su Panpan , Ma Shuangshuang , Huang Wenjuan , Boyjoo Yash , Bai Shiyang , Liu Jian
Published: July 2019

In alkaline electrolyte, Ca2+ doped cobalt based coordination polymers transformed into Ca2+ doped ultrathin CoOOH nanosheets show enhanced OER activity.
Algorithm screening to accelerate discovery of 2D metal-free electrocatalysts for hydrogen evolution reaction
Authors: Yao Sai , Zhang Xu , Chen An , Zhang Zihe , Jiao Menggai , Zhou Zhen
Published: July 2019

By using algorithm screening and DFT computations, we establish a method to accelerate the search for highly efficient HER metal-free catalysts, and a novel metal-free 2D material, a C3N monolayer, is proposed as an efficient HER catalyst.
Promoting antitumor efficacy by suppressing hypoxia via nano self-assembly of two irinotecan-based dual drug conjugates having a HIF-1α inhibitor
Authors: Zhang Bin , Huang Xiaochao , Wang Hengshan , Gou Shaohua
Published: July 2019

Conjugated a hydrophobic HIF-1α inhibitor (YC-1) with a hydrophilic anticancer drug, irinotecan (Ir), into one molecular entity, provided a new insight into the design of smart nanodrug delivery systems to hypoxic tumor tissue.
REZnAl11O19 (RE = Pr, Nd, Sm–Tb): a new family of ideal 2D triangular lattice frustrated magnets
Authors: Ashtar M. , Marwat M. A. , Gao Y. X. , Zhang Z. T. , Pi L. , Yuan S. L. , Tian Z. M.
Published: July 2019

We report the synthesis, structure and magnetic properties of a new family of rare-earth (RE) based magnetoplumbite-type REZnAl11O19 (RE = Pr–Tb) compounds with space-group P63/mmc.
Methods for the analysis of transcriptome dynamics
Authors: Rodrigues Daniela F. , Costa Vera M. , Silvestre Ricardo , Bastos Maria L. , Carvalho Félix
Published: July 2019

The transcriptome is the complete set of transcripts in a cell or tissue and includes ribosomal RNA (rRNA), messenger RNA (mRNA), transfer RNA (tRNA), and regulatory noncoding RNA. At steady-state, the transcriptome results from a compensatory variation of the transcription and decay rate to maintain the RNA concentration constant. RNA transcription constitutes the first stage in gene expression, and thus is a major and primary mode of gene expression control. Nevertheless, regulation of RNA decay is also a key factor in gene expression control, involving either selective RNA stabilization or enhanced degradation. Transcriptome analysis allows the identification of gene expression alterations, providing new insights regarding the pathways and mechanisms involved in physiological and pathological processes. Upon perturbation of cell homeostasis, rapid changes in gene expression are required to adapt to new conditions. Thus, to better understand the regulatory mechanisms associated with gene expression alterations, it is vital to acknowledge the relative contribution of RNA synthesis and decay to the transcriptome. To the toxicology field, the study of gene expression regulation mechanisms can help identify the early and mechanistic relevant cellular events associated with a particular response. This review aims to provide a critical comparison of the available methods used to analyze the contribution of RNA transcription and decay to gene expression dynamics. Notwithstanding, an integration of the data obtained is necessary to understand the entire repercussions of gene transcription changes at a system-level. Thus, a brief overview of the methods available for the integration and analysis of the data obtained from transcriptome analysis will also be provided.
Probabilistic load flow with correlated wind power sources using a frequency and duration method
Authors: Zhu Jin‐Zhou , Zhang Yan
Published: July 2019

Probabilistic load flow (PLF) is an important tool in power system planning and operation. One limitation of conventional PLF is that only the probability information of random variables is obtained as a reference for related analyses. Frequency and duration information often plays an important role in power system assessment. In this study, a frequency and duration method for PLF with correlated wind power sources and loads is proposed based on Latin hypercube sampling (LHS), Nataf transformation, and Markov chains. In the proposed method, the spatial and temporal correlations among wind power sources and loads are addressed using Nataf transformation and Markov chains, which are incorporated into the LHS framework to solve the PLF problem with frequency and duration quantities. With the proposed method, not only the probability information but also the frequency and duration information of the random output variables in a PLF problem can be efficiently and accurately obtained. The performance of the proposed PLF method is verified using comparative tests on three modified test systems.
Short‐term power load forecasting based on multi‐layer bidirectional recurrent neural network
Authors: Tang Xianlun , Dai Yuyan , Wang Ting , Chen Yingjie
Published: July 2019

Accurate power load forecasting is of great significance to ensure the safety, stability, and economic operation of the power system. In particular, short‐term power load forecasting is the basis for grid planning and decision making. In recent years, machine learning algorithms have been widely used for short‐term power load forecasting. Specifically, long short‐term memory (LSTM) and gated recurrent unit (GRU) are tailored to time series data. In this study, a multi‐layer bidirectional recurrent neural network model based on LSTM and GRU is proposed to forecast short‐term power load and is validated on two data sets. The experimental result shows that the proposed method is superior to the competition winner in the precision of forecasting on the European Intelligent Technology Network competition data. On power company data in Chongqing, considering the differences of the seasonal load, the hourly peak load of different types of load data is used for experiments. The authors separately forecast the seasonal load and compare it with LSTM, support vector regression and back propagation models. The results of the comparison show the priority of the proposed method in terms of forecasting accuracy as compared to the adopted models.
Comparison of wind turbine gearbox vibration analysis algorithms based on feature extraction and classification
Authors: Koukoura Sofia , Carroll James , McDonald Alasdair , Weiss Stephan
Published: July 2019

Health state assessment of wind turbine components has become a vital aspect of wind farm operations in order to reduce maintenance costs. The gearbox is one of the most costly components to replace and it is usually monitored through vibration condition monitoring. This study aims to present a review of the most popular existing gear vibration diagnostic methods. Features are extracted from the vibration signals based on each method and are used as input in pattern recognition algorithms. Classification of each signal is achieved based on its health state. This is demonstrated in a case study using historic vibration data acquired from operational wind turbines. The data collection starts from a healthy operating condition and leads towards a gear failure. The results of various diagnostic algorithms are compared based on their classification accuracy.
Fast and precise global maximum power point tracking techniques for photovoltaic system
Authors: Husain Mohammed Aslam , Jain Abhinandan , Tariq Abu , Iqbal Atif
Published: July 2019

The multiple power peaks obtained in the power–voltage (P‐V) curve of a photovoltaic string under partially shaded condition results in a complicated maximum power point tracking (MPPT) process. Under this condition, the conventional MPPT methods are not acknowledged as they result in false and slow tracking. In this study three novel global MPPT (GMPPT) methods have been proposed and validated. These are named as large and small duty step (LSDS), large and mutable duty step (LMDS) and fast and intelligent GMPPT (FI‐GMPPT). The LSDS method sweeps almost the entire P‐V curve using a combination of LSDS. Small duty steps are used in predefined areas near all local maximum power points of the P‐V curve. LMDS is a further improved method, which uses a combination of LMDSs. The FI‐GMPPT is an advance true GMPPT method which limits the area to be swept during the search process. This results in a further reduction in sweep time. In this method, the unnecessary area is skipped during the sweep process. The improved performance of the projected methods has been demonstrated and validated using MATLAB/SIMULINK and hardware implementation.
Reliability constraint stochastic UC by considering the correlation of random variables with Copula theory
Authors: Yu Dongmin , Ghadimi Noradin
Published: July 2019

This essay performs a reliability constraint stochastic model for unit commitment problem by considering generation and transmission constraints with high wind penetration and volatility of load demands. This query is expressed as a MILP that is based on the linear direct current model. The proposed approach models uncertainty of wind generators output power, load demand fluctuations and stochastic elements outage of the system like generators and transmission lines. In this paper, stochastic interdependence between random variables like wind speed and load demand is recognized. To establish the probability distribution of these correlated random variables, Copula theory is applied. Correlation structure between wind speed of different locations and a group of loads existing in the same area is investigated and studied based on historical data. For representing these uncertainties in the stochastic unit commitment problem, possible scenarios are generated with Monte Carlo simulation method. The reliability constraints are utilized in each scenario to evaluate the feasibility of solutions from a reliability point. The introduced stochastic UC is executed on the RTS 96‐bus test system. Numerical results demonstrate the advantages of implementing stochastic programming on the UC problem by taking into account the intermittent behavior of wind energy and load inconstancy.
Optimal automatic generation controllers in a multi‐area interconnected power system with utility‐scale PV plants
Authors: Wei Yawei , Jayawardene Iroshani , Kumar Venayagamoorthy Ganesh
Published: July 2019

The centralised utility‐scale photovoltaic (PV) plants installation has greatly enlarged their percentage in the bulk power systems, along with the nature uncertainty for the balance of system power and loads. Consequently, the successful integration of solar PV power in large‐scale power systems requires a reliable and efficient multi‐area automatic generation control (AGC) system within the control centre. Specifically, area‐AGCs that perform tie‐line bias control, in which the area frequency regulates the tie‐line power flow, must balance the operational control area supply power‐and‐demand loads within a pre‐tuned parameter set. Traditional AGC control systems have area linear controllers that must be periodically tuned to manage the high fluctuation of PV power. A practical two‐step tuning method to determine the optimal parameters of existing multi‐area AGCs is presented. The proposed method is demonstrated on a five‐area multi‐machine power system with two large PV plants. The power system was equipped with the synchrophasor‐based monitoring system, with a real‐time simulation platform serving as the application host. Results indicated that the two‐step tuning method provides optimal parameters for all the system AGCs over a wide range of PV penetration levels. Typical results demonstrated the effectiveness of the tuned multi‐area AGCs under dynamic conditions and disturbances.
Fuzzy cognitive map based approach for determining the risk of ischemic stroke
Authors: Khodadadi Mahsa , Shayanfar Heidarali , Maghooli Keivan , Hooshang Mazinan Amir
Published: July 2019

Stroke is the third major cause of mortality in the world. The diagnosis of stroke is a very complex issue considering controllable and uncontrollable factors. These factors include age, sex, blood pressure, diabetes, obesity, heart disease, smoking, and so on, having a considerable influence on the diagnosis of stroke. Hence, designing an intelligent system leading to immediate and effective treatment is essential. In this study, the soft computing method known as fuzzy cognitive mapping was proposed for diagnosis of the risk of ischemic stroke. Non‐linear Hebbian learning method was used for fuzzy cognitive maps training. In the proposed method, the risk rate for each person was determined based on the opinions of the neurologists. The accuracy of the proposed model was tested using 10‐fold cross‐validation, for 110 real cases, and the results were compared with those of support vector machine and K ‐nearest neighbours. The proposed system showed a superior performance with a total accuracy of (93.6 ± 4.5)%. The data used in this study is available by emailing the first author for academic and non‐commercial purposes.
MF‐SarNet: Effective CNN with data augmentation for SAR automatic target recognition
Authors: Zhai Yikui , Ma Hui , Cao He , Deng Wenbo , Liu Jian , Zhang Zhongyi , Guan Huixin , Zhi Yihang , Wang Jinxing , Zhou Jihua
Published: July 2019

An effective Max‐Fire CNN model MF‐SarNet for synthetic aperture radar (SAR) automatic target recognition (ATR) is presented, here. By selecting the convolution kernel of the Fire module in the network, the parameters are reduced to obtain the effective convolutional neural network of less parameter. In view of the requirement of deep learning for large‐scale data, an augmentation method is proposed, which can learn the features of large database better. The results based on MSTAR database show that the model is effective and the result is encouraging. The accuracy of SAR image recognition is 98.53%.
Design of an omnidirectional antenna with a compact size
Authors: Yang Chuo , Huo Xiao‐ning , Wang Xiao‐fei , Yang Bo‐kun , Zhang Geng
Published: July 2019

An omnidirectional antenna with a compact size is presented. The diameter of the proposed antenna is 100 mm and the height is ∼0.1λ L (12 mm). It consists of two dipoles and four shorting pins. With this configuration, the impedance bandwidth of the proposed antenna covers 2.4–2.6 GHz. Within the bandwidth, the proposed antenna has a stable bidirectional radiation pattern in the E‐plane and the omnidirectional radiation pattern in the H‐plane. The geometry of the antenna is investigated and optimised by the ANSYS high‐frequency structure simulator. The fabricated antenna is compact enough to be integrated into a communication system. Measured and simulated results are also obtained and compared at the end of this work.
Low complex direction of arrival estimation method based on adaptive filtering algorithm
Authors: Jalal Babur , Yang Xiaopeng , Igambi Denis , Ul Hassan Tehseen , Ahmad Zeeshan
Published: July 2019

Conventional subspace decomposition‐based direction of arrival (DOA) estimation methods require eigenvalue decomposition of spatial covariance matrix, therefore these methods are computationally intensive, and their implementation is difficult in real‐time applications. However, a DOA estimation method based on fixed step size least mean square (LMS) algorithm has overcome this deficiency but the suitable selection of step size is very difficult. A DOA estimation method based on the variable step size LMS algorithm is proposed in this article. In the proposed method, the step size is updated by using the estimated error signal. The spatial spectrum is obtained by the reciprocal of array pattern, where the peak values indicate the estimated DOAs of signals. The proposed method can provide better performance with low computational cost. The performance of proposed method is verified by the simulations and compared with some existing methods.
Waveform diversity design for an MIMO SAR system based on an OFDM chirp
Authors: Zhao Yujiu , Lu Xingyu , Yang Jianchao , Gu Hong , Su Weimin
Published: July 2019

Multiple‐input multiple‐output (MIMO) synthetic aperture radar (SAR) waveform diversity design has drawn extensive attention since it has a great potential in remote sensing. Waveform designing becomes one of the most significant tasks in the MIMO SAR system. In this study, a novel scheme has been proposed to generate four waveforms using an orthogonal frequency division multiplexing (OFDM) chirp waveform. The four waveforms have good auto‐correlation properties, ambiguity performance, and a good peak sidelobe ratio. This scheme makes full use of the bandwidth. The orthogonal waveform is demodulated by padding zeros and under sampling in the frequency domain. Simulation results are obtained to validate that more orthogonal waveforms can be produced by our proposal scheme with a comparative performance.
Analysis and identification of continuous line target in SAR echo based on sidelobe features
Authors: Wei Yangkai , Chen Xinliang , Fan Yujie , Ding Zegang , Wen Cheng
Published: July 2019

There are a large number of continuous line targets in the synthetic aperture radar (SAR) images of land scenes. The traditional SAR processing, which makes the continuous line targets becomes two point targets in traditional SAR images, cannot reveal the complete features of continuous line targets and cause enormous difficulties for SAR image interpretation. This study analyses the reason why traditional SAR processing cannot embody the edge characteristics of continuous line targets based on the sidelobe features of the SAR echo. The authors propose a new identification method based on the difference of the echo amplitude between continuous line target and point targets, which will help to interpret the continuous line targets in SAR images. Numerical simulation experiment based on the classical strip SAR validates the effectiveness of the proposed method.
Algebraic distributed source localisation algorithm using TDOA and AOA measurements
Authors: Liu Zhixin , Zhao Yongsheng , Jin Ke , Hu Dexiu , Wang Rui , Zhao Yongjun
Published: July 2019

This study proposes an algebraic distributed source localisation algorithm that combines time difference of arrival (TDOA) and angle of arrival (AOA) measurements. The proposed algorithm uses AOAs to remove the unknown parameters in TDOA equations caused by the specially distributed structure. Then, the observation equations are transformed into a set of pseudo‐linear equations and apply linear weighted least square to obtain the source position. The application of weighting matrix can lead to an approximate maximum likelihood estimator and produce a substantial improvement in source localisation accuracy. Both theoretical analysis and simulation results indicate the efficiency of the proposed algorithm and its performance can achieve the Cramer–Rao lower bound at a moderate noise level.
Research of wind turbine clutter mitigation based on OMP algorithm
Authors: Cao Yonggui , Fang Yu , Wu Daoqing
Published: July 2019

With the rapid development of wind power generation, the number of installed wind turbine increases rapidly. Research shows that radar echoes from wind turbines may have the potential to distract and confuse the target signal by creating false detection. To solve this problem, this study proposes a method based on orthogonal matching pursuit (OMP) algorithm for clutter mitigation. The algorithm first establishes an echo dictionary matrix and filters out clutter through loop operations. Experiments show that the method effectively filters the clutter of the wind turbine.
Electromagnetic scattering characteristics of flapping bird and experimental validation
Authors: Hu Cheng , Lang Tianjiao , Wang Rui , Liu Changjiang
Published: July 2019

Bird flight has caused many scientists' interest for a long time, of which the flapping is the most common locomotion. Radar provides a powerful tool to observe birds' migration. Aerial birds can be characterised by their electromagnetic scattering characteristics and the radar cross‐section (RCS) is one of the most important characteristics. The wings' attitudes of flying birds may induce the RCS values fluctuation; thus the authors can extract the flapping attitudes from the RCS values. In this article, a method of simulating the electromagnetic scattering characteristics of airborne birds was proposed, based on which the flapping attitudes of flapping birds in actual flights were extracted. First, electromagnetic scattering models of a flying bird with different flapping attitudes were built and the FEKO electromagnetic simulation software was used to obtain the bird target's electromagnetic scattering characteristics. Then, the relationship between the flapping angles and the RCS values of the model was studied and the parameters of the flapping angles model were estimated using a parameter estimation method. Finally, based on the measured data, the flapping attitudes of the bird in actual flights were extracted and the accuracy of the scattering model was validated.
Autofocus method for SAR image with multi‐blocks
Authors: Dong Wei , Sun Hanwei , Zhou Ruixue , Chen Hongmeng
Published: July 2019

In order to solve synthetic aperture radar image‐focus problem when space‐variant motion errors could not be ignored, this study proposes a partitioned phase gradient autofocus (PGA) method. In this method, it is most important whether the dominant scatters is in the partitioned images or not. In order to find the dominant scatters, energy gradient factor is defined and energy inflection point is determined. Then, the judgment is made by energy gradient factor and its threshold. Based on measured data processing, it is indicated that the method could distinguish the partitioned images with significant dominant scatters, un‐significant dominant scatters, and without dominant scatters. PGA is implemented on all blocks with significant dominant scatters and partial blocks with un‐significant dominant scatters. There is no need to use PGA for the blocks without dominant scatters.
Baryon acoustic oscillations at z = 2.34 from the correlations of Lyα absorption in eBOSS DR14
Authors: de Sainte Agathe Victoria , Balland Christophe , du Mas des Bourboux Hélion , Busca Nicolás G. , Blomqvist Michael , Guy Julien , Rich James , Font-Ribera Andreu , Pieri Matthew M. , Bautista Julian E. , Dawson Kyle , Le Goff Jean-Marc , de la Macorra Axel , Palanque-Delabrouille Nathalie , Percival Will J. , Pérez-Ràfols Ignasi , Schneider Donald P. , Slosar Anže , Yèche Christophe
Published: July 2019

We measure the imprint of primordial baryon acoustic oscillations (BAOs) in the correlation function of Lyα absorption in quasar spectra from the Baryon Oscillation Spectroscopic Survey (BOSS) and the extended BOSS (eBOSS) in Data Release 14 (DR14) of the Sloan Digital Sky Survey (SDSS)-IV. In addition to 179 965 spectra with absorption in the Lyman-α (Lyα) region, we use Lyα absorption in the Lyman-β region of 56 154 spectra for the first time. We measure the Hubble distance, DH, and the comoving angular diameter distance, DM, relative to the sound horizon at the drag epoch rd at an effective redshift z = 2.34. Using a physical model of the correlation function outside the BAO peak, we find DH(2.34)/rd = 8.86 ± 0.29 and DM(2.34)/rd = 37.41 ± 1.86, within 1σ from the flat-ΛCDM model consistent with CMB anisotropy measurements. With the addition of polynomial “broadband” terms, the results remain within one standard deviation of the CMB-inspired model. Combined with the quasar-Lyα cross-correlation measurement presented in a companion paper, the BAO measurements at z = 2.35 are within 1.7σ of the predictions of this model.
Legionella und Legionellose
Authors: Kolditz Martin , Lück Christian
Published: July 2019

Was ist neu?

Epidemiologie In den letzten Jahren ist eine geringe Zunahme diagnostizierter und gemeldeter Legionella-Pneumonien zu verzeichnen. Dies ist vermutlich auch der häufigeren Diagnostik zuzuschreiben.

Diagnostik Neben dem L. pneumophila Serogruppe 1-Urin-Antigen-Test sollten besonders bei schweren Verläufen zusätzlich Nukleinsäure-Amplifikationsverfahren angewendet werden. Letztere besitzen ein breiteres Spektrum und eine höhere Sensitivität.

Therapie In-vitro Resistenztestungen geben erste Hinweise, dass eine Therapie mit Levofloxacin gegenüber einer Therapie mit Makroliden überlegen sein könnte. Dies deckt sich mit aktuellen klinischen Daten aus Kohortenstudien. Levofloxacin (750–1000 mg/d) gilt bei gesicherter Legionellose als Mittel der Wahl, Alternativen sind Azithromycin oder Moxifloxacin. Eine Therapiedauer von 7 Tagen reicht in der Regel aus. Eine Resistenzentwicklung ist bisher nur vereinzelt beobachtet worden und erfordert keine routinemäßige Resistenztestung.
Update ESC-Leitlinie Synkope 2018
Authors: Clasen Lukas , Makimoto Hisaki , von Scheidt Wolfgang
Published: July 2019

Was ist neu?

Initiale Abklärung und Risikostratifizierung Die neue Leitlinie bietet eine klare Anleitung zur sicheren und effizienten Abklärung und Therapie von Patienten mit Synkopen. Neue Konzepte beinhalten Strategien zur Risikostratifizierung, vernünftigen Entscheidung für den diagnostischen Pfad sowie restriktive Kriterien für eine stationäre Aufnahme.

Diagnostische Tests Aufwertung des EKG-Monitorings mittels implantierbarem Loop-Rekorder (ILR). Bewertung des Kipptisch-Tests als Bestätigungstest bei V. a. Reflexsynkope oder Nachweis einer unspezifischen Hypotonie-Neigung. Videoaufzeichnungen durch Smartphones werden einbezogen.

Vorgehen bei ungeklärter Synkope Empfehlung zu einem klaren diagnostischen Entscheidungspfad zum Asystolie-Nachweis für Patienten > 40 Jahre mit schweren, rezidivierenden und unvorhersehbaren (ohne Prodromi einsetzenden) Synkopen.

Therapie der Synkopen Geänderte Algorithmen zur Therapie von Reflexsynkopen inkl. der seltenen Indikationsstellung zur Schrittmachertherapie. Indikation zur Implantation eines ICD (implantierbarer Kardioverter-Defibrillator) bei hohem Risiko für den plötzlichen Herztod.

Organisatorische Aspekte Interdisziplinäre Synkopen-Einheiten werden empfohlen.
Neonatal Therapeutics: Considerations for Dosing
Authors: Zimmerman Kanecia O. , Benjamin Daniel K. , Becker Mara L.
Published: July 2019

Neonates are a uniquely vulnerable population, compromised by immature physiology and critical illness if born premature. Furthermore, neonates have frequent exposures to drugs that lack adequate data on safety, efficacy, and appropriate dosing in this population. Key physiologic differences between neonates and older children and adults affect drug absorption, distribution, metabolism, and elimination. Adequate understanding and consideration of these differences is essential to ensure optimal dosing of therapeutic agents in this vulnerable population. Moreover, direct study of neonates through appropriately designed pharmacokinetic and pharmacodynamic studies can ensure the development of safe and effective therapeutics in our youngest populations of patients.
Post-trial Access in Maternal Vaccine Trials
Authors: Van Roessel I. M. A. A. , Mazur N. I. , Shah S. K. , Bont L. , Van Der Graaf R.
Published: July 2019

Provisions for post-trial access (PTA) of the experimental intervention are required before the start of a clinical trial. Although there has been ample attention for PTA in the context of preventive vaccine research, discussions on PTA barely include maternal vaccine trials in which mother–infant pairs are exposed to the intervention. In maternal vaccination trials, specific PTA arrangements are required because pregnancy is transient and PTA may apply to the next pregnancy or the child. In this article, we examine the application and adherence to PTA in the context of maternal vaccine trials. We focused on differences between publications before and after 2000 when international ethical guidance documents formalized PTA requirements. Randomized maternal vaccine trials were included after a systematic search for clinical trials in phases II and III with a maternal vaccine as intervention. We used PTA as defined at the time of publication in the World Medical Association's Declaration of Helsinki (DoH) or in the ethical guidelines of the Council for International Organizations of Medical Sciences (CIOMS). In addition, we investigated whether PTA was included in the trial design. Therefore, we contacted principal investigators (PI’s) of the publications found in the review to fill out a questionnaire regarding provisions for PTA. Before and after 2000, no trial articles examined in the systematic review described PTA in their trial publication (0/7, 0% and 0/17, 0%, respectively). In addition, more than half of the PI’s of the trials found were not familiar with PTA recommendations in international ethical guidelines. Most cases of PTA included making knowledge available by publishing the results of the trial. The revision of the DoH in 2002 and the CIOMS ethical guidelines in 2002 has not resulted in increased PTA provisions for maternal vaccination trials. PTA is a shared responsibility of various stakeholders including sponsors, Institutional Review Boards, regulators, political entities, and researchers. Inclusion of PTA provisions in trial protocols and publications on maternal vaccination trials is essential to increase transparency on the form and content of these provisions.
Update on Postnatal Corticosteroids to Prevent or Treat Bronchopulmonary Dysplasia
Authors: Filippone Marco , Nardo Daniel , Bonadies Luca , Salvadori Sabrina , Baraldi Eugenio
Published: July 2019

Bronchopulmonary dysplasia (BPD) is a major complication of premature birth that significantly affects mortality and long-term morbidity in numerous immature infants. Corticosteroids are particularly suitable for treating BPD, as lung inflammation is central to its pathogenesis. Corticosteroids have considerable, fast beneficial effects on lung function in premature infants with lung disease, but they are also associated with several serious adverse effects, which may have a detrimental impact on long-term outcome. Dexamethasone is the most often used corticosteroid for systemic administration. Despite its value in preventing and treating BPD, its use is associated with several alarming short-term effects and, worst of all, with an increased rate of cerebral palsy in the long term. Dexamethasone nonetheless remains an important therapeutic option for infants with severe lung disease beyond the second to third week of life. Hydrocortisone is an important alternative to dexamethasone, as its use does not appear to be associated with any neurotoxic effects. Its efficacy in the prevention and treatment of BPD has yet to be clearly demonstrated, however. Inhaled corticosteroids might reduce lung inflammation with fewer systemic adverse effects; however, a recent, large randomized trial showed that inhaled budesonide was associated with an excess mortality, despite its beneficial respiratory effects. In another study, instilling budesonide together with surfactant in the trachea of intubated infants with severe respiratory distress appeared safe and achieved a significant reduction in the rate of BPD at 36 postmenstrual weeks. This important finding needs to be confirmed in a larger trial currently underway.