bluuebunny/crossref_metadata_2025 huggingface dataset:
Pyrethroid exposure alters internal and cuticle surface bacterial communities in Anopheles albimanus
Authors: Dada Nsa , Lol Juan C , Benedict Ana Cristina , López Francisco , Sheth Mili , Dzuris Nicole , Padilla Norma , Lenhart Audrey
Published: June 2019

A deeper understanding of the mechanisms underlying insecticide resistance is needed to mitigate its threat to malaria vector control. Following previously identified associations between mosquito microbiota and insecticide resistance, we demonstrate for the first time, the effects of pyrethroid exposure on the microbiota of F1 progeny of field-collected Anopheles albimanus. Larval and adult mosquitoes were exposed to the pyrethroids alphacypermethrin (only adults), permethrin, and deltamethrin. While there were no significant differences in bacterial composition between insecticide-resistant and insecticide-susceptible mosquitoes, bacterial composition between insecticide-exposed and non-exposed mosquitoes was significantly different for alphacypermethrin and permethrin exposure. Along with other bacterial taxa not identified to species, Pantoea agglomerans (a known insecticide-degrading bacterial species) and Pseudomonas fragi were more abundant in insecticide-exposed compared to non-exposed adults, demonstrating that insecticide exposure can alter mosquito bacterial communities. We also show for the first time that the cuticle surfaces of both larval and adult An. albimanus harbor more diverse bacterial communities than their internal microbial niches. Together, these findings demonstrate how insecticide pressure could be selecting for certain bacteria within mosquitoes, especially insecticide-metabolizing bacteria, thus potentially contributing to insecticide resistance.
Survival of the simplest in microbial evolution
Authors: Held Torsten , Klemmer Daniel , Lässig Michael
Published: June 2019

The evolution of microbial and viral organisms often generates clonal interference, a mode of competition between genetic clades within a population. Here we show how interference impacts systems biology by constraining genetic and phenotypic complexity. Our analysis uses biophysically grounded evolutionary models for molecular phenotypes, such as fold stability and enzymatic activity of genes. We find a generic mode of phenotypic interference that couples the function of individual genes and the population’s global evolutionary dynamics. Biological implications of phenotypic interference include rapid collateral system degradation in adaptation experiments and long-term selection against genome complexity: each additional gene carries a cost proportional to the total number of genes. Recombination above a threshold rate can eliminate this cost, which establishes a universal, biophysically grounded scenario for the evolution of sex. In a broader context, our analysis suggests that the systems biology of microbes is strongly intertwined with their mode of evolution.
Unconventional topological phase transition in non-symmorphic material KHgX (X = As, Sb, Bi)
Authors: Kuo Chin-Shen , Chang Tay-Rong , Xu Su-Yang , Jeng Horng-Tay
Published: June 2019

Traditionally topological phase transition describes an evolution from topological trivial to topological nontrivial state. Originated from the non-symmorphic crystalline symmetry, we propose in this work an unconventional topological phase transition scheme between two topological nontrivial insulating states mediated by a Dirac gapless state, differing from the traditional topological phase transition. The KHgX (X = As, Sb, Bi) family is the first experimentally realized topological non-symmorphic crystalline insulator (TNCI), where the topological surface states are characterized by the Mobius-twisted connectivity. Based on first-principles calculations, we present a topological insulator–metal transition from TNCI into a Dirac semimetal (DSM) via applying an external pressure on KHgX. We find an unusual mirror Chern number Cm = −3 for the DSM phase of KHgX in the non-symmorphic crystal structure, which is topologically distinct from the traditional DSM such as Na3Bi and Cd3As2. Furthermore, we predict a new TNCI phase in KHgX via symmetry breaking. The topological surface states in this new TNCI phase display zigzag connectivity, different from the unstressed one. Our results offer a comprehensive study for understanding how the topological surface states evolve from a quantum phase transition in non-symmorphic system.
Publisher Correction: The degree of prevalence of similarity between outer tropical cyclone rainbands and squall lines
Authors: Yu Cheng-Ku , Lin Che-Yu , Cheng Lin-Wen , Luo Jhang-Shuo , Wu Chun-Chieh , Chen Ying
Published: June 2019

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.
Acoustic recordings and modeling under seasonally varying sea ice
Authors: Collins Michael D. , Turgut Altan , Menis Richard , Schindall Jeffrey A.
Published: June 2019

Acoustic data from the Canada Basin Acoustic Propagation Experiment are discussed. These recordings were obtained under seasonally varying sea ice to the north of Alaska during a period of 154 days. They contain signals from sources that were deployed at ranges of 17.5, 29.6, and 237.8 km and ambient sounds from marine mammals and ice-related events. After the area was covered with ice, the amplitude of receptions from the most distant source gradually decreased as scattering features on the underside of the ice developed during fracturing, drifting, ridging, and rafting events. Improvements are presented for an Arctic acoustic model that is based on the parabolic equation method, and the approach is applied to a problem in which variable ice thickness acts as a loss mechanism by scattering energy out of the waveguide. Some of the recordings have a harmonic signature that is believed to be associated with the resonances of ice floes rubbing together, but variations in the harmonics over short time scales cannot be explained in terms of the resonances of an isolated floe. This behavior may be related to the coupling of vibrations at contact points that vary during the relative motions of floes.
Targeted repositioning identifies drugs that increase fibroblast growth factor 20 production and protect against 6-hydroxydopamine-induced nigral cell loss in rats
Authors: Fletcher Edward J. R. , Jamieson Aran D. , Williams Gareth , Doherty Patrick , Duty Susan
Published: June 2019

Endogenous fibroblast growth factor 20 (FGF20) supports maintenance of dopaminergic neurones within the nigrostriatal pathway. Moreover, direct intracerebral infusion of FGF20 protects against nigrostriatal tract loss in the 6-hydroxydopamine lesion rat model of Parkinson’s disease. Increasing endogenous FGF20 production might provide a less-invasive, more translational way of providing such protection. Accordingly, we adopted a targeted repositioning approach to screen for candidate FDA-approved drugs with potential to enhance endogenous FGF20 production in brain. In silico interrogation of the Broad Institute’s Connectivity Map database (CMap), revealed 50 candidate drugs predicted to increase FGF20 transcription, 16 of which had profiles favourable for use in Parkinson’s disease. Of these, 11 drugs were found to significantly elevate FGF20 protein production in MCF-7 cells, between two- and four-fold. Four drugs were selected for examination in vivo. Following oral dosing in rats for 7 days, salbutamol and triflusal, but not dimethadione or trazodone, significantly elevated FGF20 levels in the nigrostriatal tract. Preliminary examination in the unilateral 6-hydroxydopamine-lesioned rat revealed a modest but significant protection against nigral cell loss with both drugs. Our data demonstrate the power of targeted repositioning as a method to identify existing drugs that may combat disease progression in Parkinson’s by boosting FGF20 levels.
Multiply-functionalized graphene oxide on-line pass-through cleanup for the fast determination of aconitum alkaloids in human plasma by LC-MS/MS
Authors: He Shi-Wei , Zhang Yun , Zhao Yong-Gang , Ye Ming-Li , Zhu Yan
Published: June 2019

A novel ionic liquid coupled with nano-titania coated modified magnetic GO composites (IL-Ti-Mag-GO) has been synthesized.
Dispersive solid-phase extraction using the metal–organic framework MIL-101(Cr) for determination of benzo(a)pyrene in edible oil
Authors: Lv Zhiyang , Yang Cheng , Pang Yuehong , Xie Weiying , Shen Xiaofang
Published: June 2019

Metal–organic frameworks MIL-101(Cr) has high efficiency for dispersive solid-phase extraction of benzo(a)pyrene in edible oil by π–π interaction and size effect.
Ultrasensitive detection of glutathione based on a switch-on fluorescent probe of AIE-type red-emitting copper nanoclusters
Authors: Du Qianqian , Hu Xue , Zhang Xiaodan , Cao Haiyan , Huang Yuming
Published: June 2019

AIE-type red-emitting Cu NCs (with a large stokes shift and high stability) are quenched with MnO2nanosheetsviaIFE, while further introduction of GSH leads to fluorescence recovery, and this finding results in a new switch-on FL fluorescence assay for ultrasensitive detection of GSH.
Aryl-viologen pentapeptide self-assembled conductive nanofibers
Authors: Clarke David E. , Olesińska Magdalena , Mönch Tobias , Schoenaers Ben , Stesmans Andre , Scherman Oren A.
Published: June 2019

We have fabricated self-assembled oligopeptide-based semiconductive nanofibers, where the electron transfer capabilities of redox-active viologens are maximized through β-sheet interactions.
An anion exchange reaction: an effective approach to prepare alloyed Co–Fe bimetallic disulfide for improving the electrocatalytic activity
Authors: Li Tongtong , Zhao Shuaishuai , Lu Yongxin , Li Zhijie , Gao Zhi-Da , Song Yan-Yan
Published: June 2019

Bimetallic disulfides prepared by a tunable anion exchange method have abundant crystal interfaces and improved hydrogen evolution activity.
Robust hydrogen evolution reaction catalysis by ultrasmall amorphous ruthenium phosphide nanoparticles
Authors: Guo Long , Luo Fang , Guo Fei , Zhang Quan , Qu Konggang , Yang Zehui , Cai Weiwei
Published: June 2019

Here, we report a facile method to synthesize ruthenium phosphides with diameter 1 nm and an amorphous structure at room temperature.
A weakly basic Co/CeOx catalytic system for one-pot conversion of cellulose to diols: Kungfu on eggs
Authors: Li Chuang , Xu Guangyue , Li Kui , Wang Chenguang , Zhang Ying , Fu Yao
Published: June 2019

A weakly basic Co/CeOx catalyst for one-pot humin-free conversion of cellulose to ethylene glycol (EG) and 1,2-propylene glycol (1,2-PG).
Porous and highly conducting cathode material PrBaCo2O6−δ: bulk and surface studies of synthesis anomalies
Authors: Bangwal Ajay S. , Jha Pardeep K. , Dubey Pawan K. , Singh Manish K. , Sinha A. S. K. , Sathe Vasant , Jha Priyanka A. , Singh Prabhakar
Published: June 2019

The paradigm that chemical synthesis reduces the sintering temperature as compared to solid state synthesis seems to be violated in the case of the PrBaCo2O6−δ double perovskite.
Wetting properties of porous high temperature polymer electrolyte fuel cells materials with phosphoric acid
Authors: Halter J. , Gloor T. , Amoroso B. , Schmidt T. J. , Büchi F. N.
Published: June 2019

The influence of phosphoric acid temperature and concentration on the wetting behavior of porous high temperature polymer electrolyte fuel cell materials is investigated.
Refractive index change dominates the transient absorption response of metal halide perovskite thin films in the near infrared
Authors: Pasanen Hannu P. , Vivo Paola , Canil Laura , Abate Antonio , Tkachenko Nikolai
Published: June 2019

Perovskite films have an uncommon, previously unreported transient absorption response in the NIR, which is caused by a change in the refractive index.
Energetics and ionization dynamics of two diarylketone molecules: benzophenone and fluorenone
Authors: Gouid Zied , Röder Anja , Cunha de Miranda Barbara K. , Gaveau Marc-André , Briant Marc , Soep Benoît , Mestdagh Jean-Michel , Hochlaf Majdi , Poisson Lionel
Published: June 2019

This paper reports on the single photon ionization of benzophenone and fluorenone and the subsequent complex dynamics fragmentation of the benzophenone cation. It shows pre-ionizing fragmentation in the case of benzophenone.
Water-soluble metal nanoclusters: recent advances in molecular-level exploration and biomedical applications
Authors: Dou Xinyue , Chen Xiaoyu , Zhu Haiguang , Liu Yong , Chen Dongyun , Yuan Xun , Yao Qiaofeng , Xie Jianping
Published: June 2019

Recent advances of water-soluble metal nanoclusters (MNCs) in designing highly luminescent MNCs, ligand shell engineering, tracking MNC's growth processes, and biomedical applications are highlighted.
KBi(IO3)3(OH) and NaBi(IO3)4: from the centrosymmetric chain to a noncentrosymmetric double layer
Authors: Jia Ying-Jie , Chen Yi-Gang , Wang Ting , Guo Yao , Guan Xiao-Fang , Zhang Xian-Ming
Published: June 2019

Two bismuth iodates via tuning of alkali–metal ions reveal a structural transition from the centrosymmetric chain to a non-centrosymmetric double layer.
Oxidation behavior of intramolecularly coordinated unsymmetrical diorganotellurides: isolation of novel tetraorganoditelluronic acids, [RR′Te(μ-O)(OH)2]2
Authors: Gupta Anand , Deka Rajesh , Sarkar Arup , Singh Harkesh B. , Butcher Ray J.
Published: June 2019

The synthesis of a series of tetraorganoditelluronic acids, [RR′Te(μ-O)(OH)2]2 has been reported.
The protective effect of protopanaxatriol-type saponin on intestinal health in antibiotic-treated mice
Authors: Zhang Minxia , Zhao Jiaqi , Deng Jianjun , Duan Zhiguang , Zhu Chenhui , Fan Daidi
Published: June 2019

This experiment is the first to explore the regulation of PPT on intestinal microbiota and integrity of the intestinal barrier.
Nip the bubble in the bud: a guide to avoid gas nucleation in microfluidics
Authors: Pereiro Iago , Fomitcheva Khartchenko Anna , Petrini Lorenzo , Kaigala Govind V.
Published: June 2019

A guide on the underlying physics, prevention and removal strategies of undesirable bubbles in microfluidics.
Non-covalent albumin-binding ligands for extending the circulating half-life of small biotherapeutics
Authors: Zorzi Alessandro , Linciano Sara , Angelini Alessandro
Published: June 2019

This review provides a detailed examination and comparison of the diverse non-covalent albumin-binding ligands developed until now to extend the half-life of different small biotherapeutics.
Correction: A siRNA-induced peptide co-assembly system as a peptide-based siRNA nanocarrier for cancer therapy
Authors: Li Wenjun , Wang Dongyuan , Shi Xiaodong , Li Jingxu , Ma Yue , Wang Yanding , Li Tingting , Zhang Jianing , Zhao Rongtong , Yu Zhiqiang , Yin Feng , Li Zigang
Published: June 2019

Correction for ‘A siRNA-induced peptide co-assembly system as a peptide-based siRNA nanocarrier for cancer therapy’ by Wenjun Li et al., Mater. Horiz., 2018, 5, 745–752.
Anchoring conductive polymeric monomers on single-walled carbon nanotubes: towards covalently linked nanocomposites
Authors: Naidek Naiane , Huang Kai , Bepete George , Rocco Maria Luiza M. , Pénicaud Alain , Zarbin Aldo J. G. , Orth Elisa S.
Published: June 2019

Chemical functionalization with conductive polymeric monomers on carbon nanotubes carried out by a straightforward method.
Aluminium complex-catalysed hydroboration of alkenes and alkynes
Authors: Harinath Adimulam , Banerjee Indrani , Bhattacharjee Jayeeta , Panda Tarun K.
Published: June 2019

Catalytic hydroboration of terminal alkenes/alkynes with HBpin using the Al(III) catalyst, [κ2-{Ph2P(=Se)NCH2(C5H4N)}Al(CH3)2] (1), under mild and solvent-free conditions to afford corresponding alkyl/alkenyl boronate esters in high yield is reported.
A three-dimensional Cd(ii) metal–organic framework: a bifunctional luminescence sensor for benzaldehyde and Fe2+ ions
Authors: Wu Ming Ze , Shi Jian Yun , Chen Peng Yun , Tian Li
Published: June 2019

A three-dimensional Cd(ii) MOF has been constructed. It is (3,6)-connected net showing rtl topology. In addition, it is also a bifunctional luminescence sensor for benzaldehyde and Fe2+ ions.
The radiation chemistry of focused electron-beam induced etching of copper in liquids
Authors: Lami Sarah K. , Smith Gabriel , Cao Eric , Hastings J. Todd
Published: June 2019

Well-controlled, focused electron-beam induced etching of copper thin films has been successfully conducted on bulk substrates in an environmental scanning electron microscope by controlling liquid-film thickness with an in situ correlative interferometry system.
Solvent-dependent photophysics of a red-shifted, biocompatible coumarin photocage
Authors: Offenbartl-Stiegert Daniel , Clarke Tracey M. , Bronstein Hugo , Nguyen Ha Phuong , Howorka Stefan
Published: June 2019

A novel coumarin photocage with long-wavelength and high photolysis quantum yield shows solvent dependent photolysis.
Nanocellulose supported hierarchical structured polyaniline/nanocarbon nanocomposite electrode via layer-by-layer assembly for green flexible supercapacitors
Authors: Lyu Shaoyi , Chen Yanping , Zhang Longfei , Han Shenjie , Lu Yun , Chen Yuan , Yang Na , Chen Zhilin , Wang Siqun
Published: June 2019

Cellulose nanofibril aerogel was used as a nanofibrous scaffold for layer-by-layer assembly of polyaniline and nano-carbons for flexible and high capacitance supercapacitor applications.
A novel ultrasensitive surface plasmon resonance-based nanosensor for nitrite detection
Authors: Miao Pandeng , Liu Zhongdong , Guo Jun , Yuan Ming , Zhong Ruibo , Wang Liping , Zhang Feng
Published: June 2019

A satellite-like AuNP aggregate-based nitrite detection nanosensor was designed via diazotization coupling reaction and can significantly lower the naked-eye detection limit to 3.0 ng mL−1. This nanosensor has important applications in food detection and cancer prevention.
New protic ionic liquids for fungi and bacteria removal from paper heritage artefacts
Authors: Dimitrić Nataša , Spremo Nemanja , Vraneš Milan , Belić Sanja , Karaman Maja , Kovačević Strahinja , Karadžić Milica , Podunavac-Kuzmanović Sanja , Korolija-Crkvenjakov Daniela , Gadžurić Slobodan
Published: June 2019

New protic ionic liquids with 1-ammonium-2-propanol cation and nine different anions were prepared in order to study their antimicrobial activity and possible application for fungi and bacteria removal from deteriorated paper heritage.
Deciphering and quantifying linear light upconversion in molecular erbium complexes
Authors: Golesorkhi Bahman , Fürstenberg Alexandre , Nozary Homayoun , Piguet Claude
Published: June 2019

Single-center linear excited state absorption (ESA) can be implemented in isolated mononuclear erbium(iii) coordination complexes, thus fixing the zero-level of quantum yields for lanthanide-based molecular light upconversion.
O species-decorated graphene shell encapsulating iridium–nickel alloy as an efficient electrocatalyst towards hydrogen evolution reaction
Authors: Gong Shipeng , Wang Changlai , Jiang Peng , Yang Kang , Lu Jian , Huang Minxue , Chen Shi , Wang Junzheng , Chen Qianwang
Published: June 2019

Oxygen species encapsulating IrNi alloy as an highly efficient electrocatalyst towards the HER in both acid and alkaline electrolytes.
Identification of core genes and clinical roles in pregnancy-associated breast cancer based on integrated analysis of different microarray profile datasets
Authors: Zhang Jiao , Zhou Yan-Jun , Yu Zhi-Hao , Chen Ao-Xiang , Yu Yue , Wang Xin , Cao Xu-Chen
Published: June 2019

More women are delaying child-birth. Thus, the diagnosis of pregnancy-associated breast cancer (PABC) will continue to increase. The aim of this study was to identify core candidate genes of PABC, and the relevance of the genes on the prognosis of PABC. GSE31192 and GSE53031 microarray profile datasets were downloaded from the Gene Expression Omnibus database and differentially expressed genes were analyzed using the R package and GEO2R tool. Then, Gene Ontology and Kyoto Encyclopedia of Gene and Genome pathway enrichment analyses were performed using the Database for Annotation, Visualization, and Integrated Discovery. Moreover, the Search Tool for the Retrieval of Interacting Genes and the Molecular Complex Detection Cytoscape software plug-in were utilized to visualize protein–protein interactions and to screen candidate genes. A total of 239 DEGs were identified in PABC, including 101 up-regulated genes mainly enriched in fatty acid activation and the fibroblast growth factor signaling pathway, while 138 down-regulated genes particularly involved in activation of DNA fragmentation factor and apoptosis-induced DNA fragmentation. Fourteen hub genes with a high degree of connectivity were selected, including CREB1, ARF3, UBA5, SIAH1, KLHL3, HECTD1, MMP9, TRIM69, MEX3C, ASB6, UBE2Q2, FBXO22, EIF4A3, and PXN. Overall survival (OS) analysis of core candidate genes was performed using the Gene Expression Profiling Interactive Analysis and UALCAN websites. High ASB6 expression was associated with worse OS of PABC patients. Molecular subtypes and menopause status were also associated with worse OS for PABC patients. In conclusion, ASB6 could be a potential predictor and therapeutic target in patient with PABC.
The Speech-Language Pathologists' Role in Mild Traumatic Brain Injury for Middle and High School–Age Children: Viewpoints on Guidelines From the Centers for Disease Control and Prevention
Authors: Brown Jessica , O'Brien Katy , Knollman-Porter Kelly , Wallace Tracey
Published: June 2019

Purpose

The Centers for Disease Control and Prevention (CDC) recently released guidelines for rehabilitation professionals regarding the care of children with mild traumatic brain injury (mTBI). Given that mTBI impacts millions of children each year and can be particularly detrimental to children in middle and high school age groups, access to universal recommendations for management of postinjury symptoms is ideal.

Method

This viewpoint article examines the CDC guidelines and applies these recommendations directly to speech-language pathology practices. In particular, education, assessment, treatment, team management, and ongoing monitoring are discussed. In addition, suggested timelines regarding implementation of services by speech-language pathologists (SLPs) are provided. Specific focus is placed on adolescents (i.e., middle and high school–age children).

Results

SLPs are critical members of the rehabilitation team working with children with mTBI and should be involved in education, symptom monitoring, and assessment early in the recovery process. SLPs can also provide unique insight into the cognitive and linguistic challenges of these students and can serve to bridge the gap among rehabilitation and school-based professionals, the adolescent with brain injury, and their parents.

Conclusion

The guidelines provided by the CDC, along with evidence from the field of speech pathology, can guide SLPs to advocate for involvement in the care of adolescents with mTBI. More research is needed to enhance the evidence base for direct assessment and treatment with this population; however, SLPs can use their extensive knowledge and experience working with individuals with traumatic brain injury as a starting point for post-mTBI care.
Phonological Learning Influences Label–Object Mapping in Toddlers
Authors: Breen Ellen , Pomper Ron , Saffran Jenny
Published: June 2019

Purpose

Infants rapidly acquire the sound patterns that characterize their native language. Knowledge of native language phonological cues facilitates learning new words that are consistent with these patterns. However, little is known about how newly acquired phonological knowledge—regularities that children are in the process of learning—affects novel word learning. The current experiment was designed to determine whether exposure to a novel phonological pattern affects subsequent novel word learning.

Method

Two-year-olds (
n
= 41) were familiarized with a list of novel words that followed a simple phonotactic regularity. Following familiarization, toddlers were taught 4 novel label–object pairs. Two of the labels were consistent with the novel regularity, and 2 of the labels were inconsistent with the regularity.

Results

Toddlers with smaller vocabularies learned all of the novel label–object pairings, whereas toddlers with larger vocabularies only learned novel label–object pairings that were consistent with the novel phonological regularity.

Conclusion

These findings demonstrate that newly learned phonological patterns influence novel word learning and highlight the role of individual differences in toddlers' representations of candidate word forms.
New strategy based modified Salp swarm algorithm for optimal reactive power planning: a case study of the Algerian electrical system (114 bus)
Authors: Mahdad Belkacem , Kamel Srairi
Published: June 2019

Optimal reactive power planning is an important task for experts and industrials to ensure the reliability of modern power systems. Actually, the structure of practical power systems becomes dynamic and characterised by uncertainty in load and non‐linear characteristic of various elements of power systems such as constraints associated to thermal units, constraints associated with FACTS devices and renewable sources. This study introduces an intelligent strategy based new metaheuristic named Salp swarm algorithm (SSA) to improve the solution of reactive power dispatch by optimising the total power loss, the total voltage deviation individually and simultaneously considering static VAR compensators (SVCs). To improve the efficiency of the original algorithm in solving large test systems, a sub SSA is formed to optimise the various objective functions based on a grouped control variable. In this study, four grouped swarms named SSA_PG for active power, SSA_VG for voltages, SSA_Ti for Tap transformers, and SSA_SVC for SVCs are formed to operate in a flexible structure to minimise a specified objective function. The proposed intelligent planning strategy validated on the IEEE 30 bus and to the large electrical test system 114 Bus of the Algerian network at normal condition and considering critical situations such as margin loading stability and contingency. Results found using the proposed strategy compared to those cited recently in the literature proves its particularity in terms of solution quality and convergence characteristics.
Contribution of travelling wave propagation time to the speed of optical link protections in multi‐terminal high‐voltage DC systems
Authors: Johannesson Niclas , Norrga Staffan
Published: June 2019

During faults in multi‐terminal high‐voltage DC systems, the disturbance will quickly become evident throughout the entire system. If DC breakers are included in such systems, the entire fault clearing process needs to occur within a few milliseconds. Therefore, DC line protection schemes based on telecommunication have previously been discarded by some authors as their performance is constrained by the communication delay. However, telecommunication‐based detection methods offer some very favourable features, one being that selectivity can be achieved without coordination of settings. In this study, several telecommunication‐based protection schemes are evaluated with regards to their minimum possible detection time when considering telecommunication delay. It is shown that they perform best during faults located at the remote end of a line, i.e. fault locations that are difficult to reliably detect using single‐ended methods. Therefore, it is reasonable that the most reliable protection system will consist of both single‐ended and communication‐based methods because they complement each other well. Furthermore, it is shown that the travelling wave differential protection offers the shortest theoretical detection time due to the wave propagation delay being included in the formulation.
Multi‐objective synergistic planning of EV fast‐charging stations in the distribution system coupled with the transportation network
Authors: Shukla Akanksha , Verma Kusum , Kumar Rajesh
Published: June 2019

The adoption of environmentally friendly electric vehicles (EVs) is increasing over the years due to the increased awareness of energy and environmental challenges. However, the current growth is slow because of lack of proper charging infrastructures. This study proposes a multi‐objective synergistic planning model of an EV charging station considering the interaction between the distribution system and transportation networks as the fast charging of EVs affects the operation of both networks. The developed model minimises the power losses and voltage deviation of the distribution system and maximises the EV flow served by the fast charging station (FCS) simultaneously taking into account permissible waiting time and service radius of FCS. Multi‐objective grey wolf optimiser (MOGWO) algorithm is used to obtain the non‐dominated solutions and fuzzy satisfaction‐based decision‐making method is employed to reach final planning scheme. The effectiveness of the proposed model is investigated on the IEEE 123‐bus distribution system coupled with a 25‐node transportation network. The influence of different objectives, service radius and waiting time on the planning of FCS is also explored. Results reveal that the developed method can provide rational siting and sizing of FCS and it is also found that proper service radius and waiting time provide more convenience to the customer.
Local difference‐based active contour model for medical image segmentation and bias correction
Authors: Niu Yuefeng , Cao Jianzhong
Published: June 2019

This study proposes a local bias field and difference estimation (LBDE) model for medical image segmentation and bias field correction. Firstly, the LBDE model uses a linear combination of a given set of smooth orthogonal basis functions, which is called Chebyshev polynomial, to estimate the bias field. Then, a clustering criterion function is defined by considering the difference between the measured image and approximated image in a small region. By applying this difference in the local region, the LBDE model can obtain accurate segmentation results and estimation of the bias field. Finally, the energy functional is incorporated into a level set formulation with a regularisation term, and it is minimised via the level set evolution process. The LBDE model first appears as a two‐phase model and then extends to the multi‐phase one. Extensive experiments on medical images demonstrate that the LBDE model achieves more precise segmentation results in terms of Jaccard similarity and dice similarity coefficient than the comparative models. Therefore the proposed model can increase the segmentation accuracy and robustness to noise.
Video retargeting through spatio‐temporal seam carving using Kalman filter
Authors: Kaur Harpreet , Kour Swarnjeet , Sen Debashis
Published: June 2019

A Kalman filter‐based spatio‐temporal seam determination scheme is proposed in this study for video retargeting through seam carving. In probably a first, the authors’ retargeting approach is designed to be hardware friendly, and to achieve spatial and temporal coherence through an optimal solution with explicit mechanisms to reduce jitter and structural distortion. In a video frame, while spatially coherent seam is determined by the popular approach of seam energy minimisation, temporally coherent seam is determined using Kalman prediction and updation processes. Further, these spatial and temporal seams are combined judiciously to obtain the spatio‐temporal seam to be removed/repeated for decreasing/increasing the frame size. The authors show that the proposed Kalman filter‐based approach has less theoretical complexity compared to the existing. Extensive experimental results show that the proposed approach consistently outperforms the state‐of‐the‐art, both qualitatively and quantitatively in performance, and in computational time.
Dual‐band miniaturised FSS with stable resonance frequencies of 3.4/4.9 GHz for 5G communication systems applications
Authors: Wang Hui , Qu Shaobo , Wang Jiafu , Yan Mingbao , Zheng Lin
Published: June 2019

In this study, a convoluted and connecting unit structure to design a frequency selective surface (FSS) with miniaturised closely spaced dual‐bandstop is presented. Using −10 dB transmissions as the threshold for operating bandwidth, the proposed FSS possesses two stopbands with central operating frequencies of 3.4 GHz and 4.9 GHz with bandwidths of 950 MHz (2.80–3.75 GHz) and 850 MHz (4.55–5.4 GHz), respectively, and a band ratio of just 1.44. The unit dimension of the proposed FSS is 0.069λ1 × 0.069λ1, where λ1 represents the first resonant wavelength in free space. This FSS structure exhibits excellent miniaturisation properties. In addition, the proposed FSS exhibits excellent stability for both transverse electric (TE) and transverse magnetic (TM) polarisations under incident angles from 0° to 60°. Finally, the FSS sample was fabricated and measured. The simulation results are in good agreement with the measured results. The biggest innovation of this study is to use the old method to solve the new problem, that is, to realise the shielding of fifth‐generation (5G) signal by using the method of convoluted and connecting FSS. The design will be of significance in further development of 5G communications.
Equivalent source and pattern reconstruction from oversampled measurements in highly‐reflective environments
Authors: Knapp Josef , Kornprobst Jonas , Eibert Thomas F.
Published: June 2019

Measurement errors due to echoes are a major challenge for accurate antenna pattern measurements. In particular in highly‐reflective measurement environments, the echo contribution can easily have more influence on the measurement signal than the desired line‐of‐sight contribution between the antenna under test and the measurement probe. A large number of redundant measurement samples at different locations and for different frequencies is used together with appropriate post‐processing techniques to mitigate the echo influences on the measurements. The frequency diversity is used for time gating. A virtual array, less sensitive to the undesired echo fields, is formed using probe diversity. In this work, the common time gating technique is enhanced and the impact of different probe configurations for creating a virtual array is investigated. The utilised time gating method extends the measured frequency domain signal to mitigate the Gibbs phenomenon. Processing measurements in a quasi‐metallic room, the signal contributions at the edges of the measured bandwidth do not suffer from distortions with the enhanced time gating method. Combining up to 115 probes to form a virtual array, it is found that the results improve with an increasing number of probes as long as the probes are distant enough from the walls.
Design and operation of an OCC‐based scheme for a stand‐alone PV system powering DC loads
Authors: de Carvalho Neto João T. , Salazar Andrés O. , Lock Alberto S.
Published: June 2019

Distributed energy resources such as stand‐alone photovoltaic (PV) systems have been widely used in electric systems in the last decades due to the increase in global energy demand, and the concern about the environmental problems caused by fossil fuels power generation. Owing to the fast growing of direct current (DC) microgrids and electronic devices, such as their current compatibility nature in relation to primary sources, a small‐scale stand‐alone PV system with battery storage for DC applications is proposed in this work. The system consists of three DC–DC converters which operate according to the PV panel power and the main bus load demand. The control of these converters considers the quality in power supply ensuring safety to the loads and batteries of the system. Thus, this study proposes the implementation of the control units through the use of one‐cycle control (OCC) which allows fast response to transient conditions, great accuracy of convergence and has low‐cost analogue implementation. In this study, one‐cycle controllers’ waveforms are analysed in steady‐state conditions and its duty cycles are compared with the expected in relation to the system operation. Simulations of transition conditions were performed through real situations such as cloud‐edge effects, slow passing clouds and absence of sunlight.
Clutter and distortion products suppression methods for code division multiple access systems
Authors: Stukovska Petra , Plsek Radek
Published: June 2019

This study summarises effort to design and optimise clutter and distortion products suppression method for multi‐static primary surveillance radar (MSPSR) system working with code division multiple access. Proposed methods have been designed based on clutter suppression algorithm used in frequency division multiple access systems with an emphasis on computational complexity. Further research has been focused on suppression and also other distortion products in a received signal, those are mostly caused by the phase noise of transmitters and receiver. Finally, the optimal setting of designed methods has been investigated, which is mainly focused on orthogonalisation process of base matrices and time frame length for clutter suppression. Performance of proposed algorithms is compared on both simulated and real signal from the MSPSR system and also for numerical precision single versus double.
A novel outlier removal method for two‐dimensional radarodometry
Authors: Scannapieco Antonio F.
Published: June 2019

Autonomous navigation of platforms in complex environments has a key role in many applications. However, environmental conditions could negatively affect the performance of electro‐optical sensors. Hence, the idea of using radar odometry (RO) has been recently developed. However, it suffers from the presence of outliers in the scene as its electro‐optical counterparts. This work presents a method to classify radar echoes as inliers or outliers for two‐dimensional RO, based on their range rate and bearing angle. The range rate and bearing angle are, in fact, combined to give a classification value, different for each target. At each acquisition time, the median of all classification values is computed. Since classification values of stationary targets, i.e. the inliers, cluster around the median, while moving targets, i.e. the outliers, exhibit larger distance from the median, stationary targets and moving targets can be separated. This is also useful for sense‐and‐avoid purposes. The method has been tested in the simulated scenario to show effectiveness in detecting outliers and in a real‐case scenario to demonstrate significant improvement in the reconstruction of the trajectory of the platform, keeping the final error around 10% of the travelled distance. Further improvement is envisaged by integrating the method in the target tracking strategy.
Noise mitigation in dual three‐phase internal permanent magnet machines by injection of current harmonics
Authors: Hollstegge Philipp , Wanke Andreas , De Doncker Rik W.
Published: June 2019

Steadily increasing power demands are linked with the ongoing process of electrifying the powertrain for dominant and pure electric vehicles. Fulfilling those requirements can be achieved by a multiphase approach which is implemented with a six‐phase machine with buried permanent magnets. Besides the new modelling aspects, new control possibilities arise such as controlling the current harmonics individually using vector space decomposition (VSD) methods. Here, this method is used to influence the noise, vibration and harshness (NVH) maintaining the working point in torque and speed. A reduction up to 22 dB of the main acoustic order in the significant speed range was achieved.
Study on the day‐ahead co‐operation strategy of regional integrated energy system including CCHP
Authors: Zhu Shaojie , Liu Haoming , Xu Jieyan , Chen Zheng , Niu Man
Published: June 2019

Energy is usually used in the form of cool, heat and electricity power in industrial park and town. Different types of energy are often coupled in generation, convention, storage and usage sides, especially with the existence of energy storage devices. Under this background, considering coupling of cold, heat and power in a regional energy system, this paper researches on the day‐ahead co‐operation strategy of regional combined cool, heat and power (CCHP) system. Based on modelling of typical equipment in the regional integrated system, a day‐ahead co‐operation strategy is proposed with the objective function to minimize daily operation cost of the CCHP system. The established mixed‐inter non‐linear programming model is solved by CPLEX mathematical programming software. Case study results demonstrate the feasibility and effectiveness of the proposed co‐operation strategy of regional CCHP system.
State‐of‐Charge estimation of Li‐ion battery at different temperatures using particle filter
Authors: Sangwan Venu , Kumar Rajesh , Kumar Rathore Akshay
Published: June 2019

State‐of‐Charge (SOC) estimation is one of the fundamental functions undertaken by Battery Management System (BMS) in an Electric Vehicle (EV) to assess the residual service time of the battery during operation. Thus, an accurate model of the battery that efficiently describes its dynamic characteristics is necessary for precise SOC estimation. The variation in temperature effects battery parameters, and consequently, the estimation of SOC is subject to change in temperature. In this paper, the identification of parameters of battery model is considered as an optimisation problem and solved using meta‐heuristic Ageist Spider Monkey Algorithm (ASMO) under the influence of varying temperature. The developed model is used for SOC estimation using three Recursive Bayesian filtering based adaptive filter algorithms. Further, the efficiency of the implemented adaptive filter algorithms is compared in terms of solution quality and computation time required for evaluation of SOC.
Impact of renewable energy balancing power in tertiary balancing market on Japanese power system based on automatic generation control standard model
Authors: Jie Bo , Tsuji Takao , Uchida Kenko
Published: June 2019

Due to the environmental burden, natural hazard and energy dilemma in Japan, renewable energy integration has become a key technology in the development of power systems and there has been significant increase in the use of wind and solar power generation. With the development of technologies and free fuel source offering, renewable energy power has been widely used in power system all over the world. On the other hand, because of diversification of generation operating in power system, it becomes more and more important to ensure the security and stability of power system in terms of supply–demand balance with a proper frequency range, to this end, balancing market has been developed in some European countries and regions in order to purchase the balancing power capacity and energy efficiently. In Japan, with the feed‐in tariff policy spreading from 2012, it becomes a possibility that renewable energy balancing power participating in balancing market which will be newly established in 2020.
Test of PV inverters under unbalanced operation
Authors: Wang Ziyu , Rasmussen Theis Bo , Yang Guangya
Published: June 2019

In the modern renewable energy system, recent years have seen a rise in the share of power being generated through photovoltaic (PV) plants. In the Danish power system, PV plants are mostly integrated in the medium‐ and low‐voltage networks which are usually operating under unbalanced conditions. Furthermore, the increasing number of power‐electronic‐based equipment affects the grid during faults through their contribution to the fault current. So far studies of PV plants in unbalanced conditions are based on computational simulations, which have limitations in representing reality. Therefore, this study investigated the performance of a three‐phase PV inverter under unbalanced operation and fault conditions. The inverter is tested in stable power system operation and during grid support situations through frequency response and reactive power control. All experiments are carried out using an experimental laboratory platform in PowerLabDK. The key outcomes from this study includes the correlation between positive sequence component of voltage and reactive power, active power and current under unbalanced operation, the frequency response dependence on positive sequence voltage, and the fault current contribution from PV inverter during different fault conditions.
Dissecting bombs and bursts: non-LTE inversions of low-atmosphere reconnection in SST and IRIS observations
Authors: Vissers G. J. M. , de la Cruz Rodríguez J. , Libbrecht T. , Rouppe van der Voort L. H. M. , Scharmer G. B. , Carlsson M.
Published: June 2019

Ellerman bombs and UV bursts are transient brightenings that are ubiquitously observed in the lower atmospheres of active and emerging flux regions. As they are believed to pinpoint sites of magnetic reconnection in reconfiguring fields, understanding their occurrence and detailed evolution may provide useful insight into the overall evolution of active regions. Here we present results from inversions of SST/CRISP and CHROMIS, as well as IRIS data of such transient events. Combining information from the Mg II h & k, Si IV, and Ca II 8542 Å and Ca II H & K lines, we aim to characterise their temperature and velocity stratification, as well as their magnetic field configuration. We find average temperature enhancements of a few thousand kelvin, close to the classical temperature minimum and similar to previous studies, but localised peak temperatures of up to 10 000–15 000 K from Ca II inversions. Including Mg II appears to generally dampen these temperature enhancements to below 8000 K, while Si IV requires temperatures in excess of 10 000 K at low heights, but may also be reproduced with secondary temperature enhancements of 35 000–60 000 K higher up. However, reproducing Si IV comes at the expense of overestimating the Mg II emission. The line-of-sight velocity maps show clear bi-directional jet signatures for some events and strong correlation with substructure in the intensity images in general. Absolute line-of-sight velocities range between 5 and 20 km s−1 on average, with slightly larger velocities towards, rather than away from, the observer. The inverted magnetic field parameters show an enhancement of the horizontal field co-located with the brightenings at heights similar to that of the temperature increase. We are thus able to largely reproduce the observational properties of Ellerman bombs with the UV burst signature (e.g. intensities, profile asymmetries, morphology, and bi-directional jet signatures), with temperature stratifications peaking close to the classical temperature minimum. Correctly modelling the Si IV emission in agreement with all other diagnostics is however an outstanding issue and remains paramount in explaining its apparent coincidence with Hα emission. Fine-tuning the approach (accounting for resolution differences, fitting localised temperature enhancements, and/or performing spatially coupled inversions) is likely necessary in order to obtain better agreement between all considered diagnostics.