bluuebunny/crossref_metadata_2025 huggingface dataset:
Author Correction: Multifunctional light beam control device by stimuli-responsive liquid crystal micro-grating structures
Authors: Algorri J. F. , Morawiak P. , Zografopoulos D. C. , Bennis N. , Spadlo A. , Rodríguez-Cobo L. , Jaroszewicz L. R. , Sánchez-Pena J. M. , López-Higuera J. M.
Published: December 2020

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Genetic ancestry, skin pigmentation, and the risk of cutaneous squamous cell carcinoma in Hispanic/Latino and non-Hispanic white populations
Authors: Jorgenson Eric , Choquet Hélène , Yin Jie , Hoffmann Thomas J. , Banda Yambazi , Kvale Mark N. , Risch Neil , Schaefer Catherine , Asgari Maryam M.
Published: December 2020

Although cutaneous squamous cell carcinoma (cSCC) is one of the most common malignancies in individuals of European ancestry, the incidence of cSCC in Hispanic/Latinos is also increasing. cSCC has both a genetic and environmental etiology. Here, we examine the role of genetic ancestry, skin pigmentation, and sun exposure in Hispanic/Latinos and non-Hispanic whites on cSCC risk. We observe an increased cSCC risk with greater European ancestry (P = 1.27 × 10−42) within Hispanic/Latinos and with greater northern (P = 2.38 × 10−65) and western (P = 2.28 × 10−49) European ancestry within non-Hispanic whites. These associations are significantly, but not completely, attenuated after considering skin pigmentation-associated loci, history of actinic keratosis, and sun-protected versus sun-exposed anatomical sites. We also report an association of the well-known pigment variant Ala111Thr (rs1426654) at SLC24A5 with cSCC in Hispanic/Latinos. These findings demonstrate a strong correlation of northwestern European genetic ancestry with cSCC risk in both Hispanic/Latinos and non-Hispanic whites, largely but not entirely mediated through its impact on skin pigmentation.
Microfluidic platform enables tailored translocation and reaction cascades in nanoliter droplet networks
Authors: Bachler Simon , Haidas Dominik , Ort Marion , Duncombe Todd A. , Dittrich Petra S.
Published: December 2020

In the field of bottom-up synthetic biology, lipid membranes are the scaffold to create minimal cells and mimic reactions and processes at or across the membrane. In this context, we employ here a versatile microfluidic platform that enables precise positioning of nanoliter droplets with user-specified lipid compositions and in a defined pattern. Adjacent droplets make contact and form a droplet interface bilayer to simulate cellular membranes. Translocation of molecules across membranes are tailored by the addition of alpha-hemolysin to selected droplets. Moreover, we developed a protocol to analyze the translocation of non-fluorescent molecules between droplets with mass spectrometry. Our method is capable of automated formation of one- and two-dimensional droplet networks, which we demonstrated by connecting droplets containing different compound and enzyme solutions to perform translocation experiments and a multistep enzymatic cascade reaction across the droplet network. Our platform opens doors for creating complex artificial systems for bottom-up synthetic biology.
Reverse Chromatin Immunoprecipitation (R-ChIP) enables investigation of the upstream regulators of plant genes
Authors: Wen Xuejing , Wang Jingxin , Zhang Daoyuan , Ding Yu , Ji Xiaoyu , Tan Zilong , Wang Yucheng
Published: December 2020

DNA binding proteins carry out important and diverse functions in the cell, including gene regulation, but identifying these proteins is technically challenging. In the present study, we developed a technique to capture DNA-associated proteins called reverse chromatin immunoprecipitation (R-ChIP). This technology uses a set of specific DNA probes labeled with biotin to isolate chromatin, and the DNA-associated proteins are then identified using mass spectrometry. Using R-ChIP, we identified 439 proteins that potentially bind to the promoter of the Arabidopsis thaliana gene AtCAT3 (AT1G20620). According to functional annotation, we randomly selected 5 transcription factors from these candidates, including bZIP1664, TEM1, bHLH106, BTF3, and HAT1, to verify whether they in fact bind to the AtCAT3 promoter. The binding of these 5 transcription factors was confirmed using chromatin immunoprecipitation quantitative real-time PCR and electrophoretic mobility shift assays. In addition, we improved the R-ChIP method using plants in which the DNA of interest had been transiently introduced, which does not require the T-DNA integration, and showed that this substantially improved the protein capture efficiency. These results together demonstrate that R-ChIP has a wide application to characterize chromatin composition and isolate upstream regulators of a specific gene.
Small-molecule Inhibitors of Myc–Max Interaction and DNA Binding
Authors: Fletcher Steven , Prochownik Edward V.
Published: December 2020

c-Myc (Myc) is among the most frequently dysregulated oncoproteins, thus making it a high value cancer therapy target. However, because it is a transcription factor with no intrinsic enzymatic activity, and because Myc is rarely mutated in cancer, the design of specific pharmacologic inhibitors has been a frustrating enterprise and Myc has long been viewed as being “undruggable”. However, a number of structurally diverse compounds that appear to have two distinct mechanisms of action have been developed over the past several years. The first involves the interaction of the compound with different regions of Myc's basic-helix-loop-helix-leucine zipper (HLH-Zip) dimerization domain. The ensuing distortion prevents Myc's interaction with its obligate bHLH-Zip heterodimerization partner, Max, and binding to its specific genomic sites. The second involves binding of the small-molecule to pre-formed Myc–Max heterodimers and the alteration of the latter's structure in a manner that abrogates DNA binding while preserving the Myc–Max heterodimer. We review here the history of these compounds and discuss recent progress toward achieving greater potency and pharmacologic optimization.
Small Molecule Modulators of Endo-lysosomal Toll-like Receptors
Authors: Talukdar Arindam , Mukherjee Ayan , Ganguly Dipyaman
Published: December 2020

TLRs are germline-encoded pattern recognition receptors and are a critical first line of defense for self–nonself discrimination by the host immune response. The major group of TLRs (TLR1, 2, 4, 5, 6 and 10) is expressed on the cell surface and recognizes lipids, lipopeptides and proteins. Another group of TLRs (TLR3, 7, 8, 9) is expressed in the endosomal compartments, instead of the cell surface, and recognizes pathogen-derived nucleic acids. This chapter mainly focuses on the endo-lysosomal TLRs. It describes the structural components of TLRs and their modulation through specific ligands with respect to agonists and antagonists. The efforts toward the development of specific small molecule agonists and antagonists for the endo-lysosomal TLRs, which play an important role in different clinical contexts, have been depicted. Agonists have the ability to bind and function as immune response enhancers, whereas antagonists have the ability to block the response generated by the action of agonists and can stop aberrant activation of immune responses. Agonists have been extensively explored as useful therapeutic agents as well as adjuvants in cancer and infectious diseases. Antagonists have a therapeutic role in suppressing the overactive immune response in chronic inflammatory and autoimmune disorders.
ZnO nanoparticles as photodegradation agent controlled by morphology and boron doping
Authors: Furka Daniel , Furka Samuel , Naftaly Mira , Rakovský Erik , Čaplovičová Mária , Janek Marián
Published: December 2020

ZnO nanoparticles with different morphology and doping possess different atomic planes at their interfaces. This changed their catalytic efficiency during degradation experiments with dyes, significantly dependent also on used dopant concentrations.
Molybdenum tricarbonyl complex functionalised with a molecular triazatriangulene platform on Au(111): surface spectroscopic characterisation
Authors: Petersen Finn , Lautenschläger Irene , Schlimm Alexander , Flöser Benedikt M. , Jacob Hanne , Amirbeigiarab Reihaneh , Rusch Talina R. , Strunskus Thomas , Magnussen Olaf , Tuczek Felix
Published: December 2020

A Mo(0) tricarbonyl unit supported by a tripod ligand was bound to a triazatriangulene platform, and the resulting complex was deposited on a Au(111) surface. The corresponding monolayer was characterized with STM, XPS, NEXAFS and IRRAS.
Upconversion luminescence and temperature sensing characteristics of Yb3+/Tm3+:KLa(MoO4)2phosphors
Authors: Zhang Yuhong , Wang Bo , Liu Yunhe , Bai Guangyao , Fu Zuoling , Liu Hang
Published: December 2020

UC spectra of KLa(MoO4)2: Yb3+/Tm3+at different temperature.
Interactions with freshwater biofilms cause rapid removal of common herbicides through degradation – evidence from microcosm studies
Authors: Bighiu Maria Alexandra , Goedkoop Willem
Published: December 2020

We found that biofilms drive the removal of bentazone, metazachlor and metribuzin from water through rapid mineralization of these herbicides, rather than by their sorption and accumulation.
Drinking water contamination from the thermal degradation of plastics: implications for wildfire and structure fire response
Authors: Isaacson Kristofer P. , Proctor Caitlin R. , Wang Q. Erica , Edwards Ethan Y. , Noh Yoorae , Shah Amisha D. , Whelton Andrew J.
Published: December 2020

Plastic pipes are susceptible to thermal degradation which can produce volatile organic compounds such as benzene, toluene, ethylbenzene, and xylene that leach into drinking water.
In situ identification of the electrocatalytic water oxidation behavior of a nickel-based metal–organic framework nanoarray
Authors: Cheng Fanpeng , Li Zhongjian , Wang Lin , Yang Bin , Lu Jianguo , Lei Lecheng , Ma Tianyi , Hou Yang
Published: December 2020

Direct identification of electrocatalytic behavior changes for highly efficient metal–organic framework based oxygen evolution reaction electrocatalysts is explored.
Threshold switching memristor-based stochastic neurons for probabilistic computing
Authors: Wang Kuan , Hu Qing , Gao Bin , Lin Qi , Zhuge Fu-Wei , Zhang Da-You , Wang Lun , He Yu-Hui , Scheicher Ralph H. , Tong Hao , Miao Xiang-Shui
Published: December 2020

Stochastic neurons based on CuS/GeSe conductive bridge threshold switching memristors are designed to mimic the probabilistic computing ability of the brain at a hardware level.
Ultra-broadband photon harvesting in large-area few-layer MoS2 nanostripe gratings
Authors: Bhatnagar Mukul , Giordano Maria Caterina , Mennucci Carlo , Chowdhury Debasree , Mazzanti Andrea , Della Valle Giuseppe , Martella Christian , Tummala Pinakapani , Lamperti Alessio , Molle Alessandro , Buatier de Mongeot Francesco
Published: December 2020

Flat optics photon harvesting, based on cm-scale MoS2 nanostripe arrays, induces an ultra-broadband enhancement (≈400%) of optical absorption.
Catalytic polymersomes to produce strong and long-lasting bioluminescence
Authors: Meyer Claire Elsa , Craciun Ioana , Schoenenberger Cora-Ann , Wehr Riccardo , Palivan Cornelia Gabriela
Published: December 2020

Polymersome-based bioluminescent nanocompartment to achieve enzyme protection and switch kinetics to produce a persistent light signal.
Theoretically guiding the construction of a novel Cu2O@Cu97P3@Cu3P heterojunction with a 3D hierarchical structure for efficient photocatalytic hydrogen evolution
Authors: Zhang Lijun , Jin Zhiliang
Published: December 2020

Using photocatalysis to produce clean H2 energy has been considered as one of the ideal strategies to alleviate the energy crisis and environmental pollution.
On-demand mixing and dispersion in mini-pillar based microdroplets
Authors: Fan Chuan , Luo Yong , Xu Tailin , Song Yongchao , Zhang Xueji
Published: December 2020

The analysis and detection of ultra-trace biomarkers are often carried out in microliter droplets.
Digital light processing 3D printing with thiol–acrylate vitrimers
Authors: Rossegger Elisabeth , Höller Rita , Reisinger David , Strasser Jakob , Fleisch Mathias , Griesser Thomas , Schlögl Sandra
Published: December 2020

The customized fabrication of soft active devices with self-healing function is demonstrated by 3D printing with vitrimeric thiol–acrylate photopolymers.
Molecular oxofluorides OMFnof nickel, palladium and platinum: oxyl radicals with moderate ligand field inversion
Authors: Li Lin , Beckers Helmut , Stüker Tony , Lindič Tilen , Schlöder Tobias , Andrae Dirk , Riedel Sebastian
Published: December 2020

High-valent late transition metal oxo compounds attracted attention because of their peculiar metal–oxygen bond. Their oxo ligands exhibit an electrophilic and distinct radical oxyl (O˙−) rather than the more common nucleophilic (O2−) character.
Synthesis of novel star-shaped molecules based on a 1,3,5-triazine core linked to different heterocyclic systems as novel hybrid molecules
Authors: Diab Hadeer M. , Salem Mostafa E. , Abdelhamid Ismail A. , Elwahy Ahmed H. M.
Published: December 2020

The synthesis of novel star-shaped compounds based on ans-triazine core and linked to different heterocycles as new hybrid molecules through Michael and Hantzsch reactions is reported.
Small molecules targeting the NEDD8·NAE protein–protein interaction
Authors: Lin Chen-Ming , Jiang Zhengyang , Gao Zhe , Arancillo Maritess , Burgess Kevin
Published: December 2020

Discovery of the first NEDDylation inhibitor, that targets the NEDD8·NAE protein–protein interaction, was acheived using the Exploring Key Orientations (EKO) approach.
Tailoring the cavities of hydrogen-bonded amphidynamic crystals using weak contacts: towards faster molecular machines
Authors: Navarro-Huerta Armando , Jellen Marcus J. , Arcudia Jessica , Teat Simon J. , Toscano Rubén A. , Merino Gabriel , Rodríguez-Molina Braulio
Published: December 2020

This work describes the use of C–H⋯F–C contacts in the solid-state from the stator towards the rotator to fine-tune their internal motion, by constructing a set of interactions that generate close-fitting cavities in three supramolecular rotors 1–3I.
Hydantoin-bridged medium ring scaffolds by migratory insertion of urea-tethered nitrile anions into aromatic C–N bonds
Authors: Millward Makenzie J. , Ellis Emily , Ward John W. , Clayden Jonathan
Published: December 2020

Bicyclic or tricyclic nitrogen-containing heterocyclic scaffolds were constructed rapidly by ring expanding intramolecular SNAr on a series of electronically unactivated heterocyclic precursors.
Synchronous nesting of hollow FeP nanospheres into a three-dimensional porous carbon scaffold via a salt-template method for performance-enhanced potassium-ion storage
Authors: Tan Qiwei , Han Kun , Zhao Wang , Li Ping , Liu Zhiwei , Li Shengwei , Qu Xuanhui
Published: December 2020

The synchronous nesting of hollow FeP nanospheres into a 3D-PC scaffold is designed for boosting the electrochemical performance of KIBs.
Interfacial advances yielding high efficiencies for thermoelectric devices
Authors: Wu Wenjie , Ren Guang-Kun , Chen Xuxuan , Liu Yinke , Zhou Zhifang , Song Jiangfeng , Shi Yan , Jiang Jia-Ming , Lin Yuan-Hua
Published: December 2020

Advances in material interface, electrode interface and protective layer interface demonstrate the potential of thermoelectric devices for large-scale power generation applications.
Strategies of tuning catalysts for efficient photodegradation of antibiotics in water environments: a review
Authors: Wu Suqing , Lin Yan , Hu Yun Hang
Published: December 2020

To solve the pollution issues of antibiotics in water, various strategies have been explored to develop efficient photocatalysts for the degradation of antibiotics.
Modelling of heterogeneous ion transport in conducting polymer supercapacitors
Authors: Bamgbopa Musbaudeen O. , Belaineh Dagmawi , Mengistie Desalegn A. , Edberg Jesper , Engquist Isak , Berggren Magnus , Tybrandt Klas
Published: December 2020

The characteristics of conducting polymer supercapacitors are understood by modelling of heterogeneous ion transport within the electrodes.
Diamine tailored smooth and continuous perovskite single crystal with enhanced photoconductivity
Authors: Yang Wantian , Hu Jiarui , Chen Jian , Xu Yaxin , Tong Guoliang , Fan Haotian , Chai Xingchen , Chen Junnian , He Yunbin
Published: December 2020

2D pentamethylenediammonium lead bromide single crystal with distinctive smooth and continuous morphology and decreased interlayer distance exhibits promising photoconductivity performance.
Clinical Science Editorial 2020 – a year gone by and the year ahead
Authors: Touyz Rhian M.
Published: December 2020

As this extraordinary year, blemished by COVID-19, comes to an end, I look back as Editor-in-Chief to the many great successes and new initiatives of Clinical Science. Despite the challenges we all faced during 2020, our journal has remained strong and vibrant. While we have all adapted to new working conditions, with life very different to what it was pre-COVID-19, the one thing that remains intact and secure is the communication of scientific discoveries through peer-reviewed journals. I am delighted to share with you some of the many achievements of our journal over the past year and to highlight some exciting new activities planned for 2021.
Child–Parent–Provider Interactions of a Child With Complex Communication Needs in an Inpatient Rehabilitation Facility: A Pilot Study
Authors: Gormley Jessica , Light Janice
Published: December 2020

Purpose

Children with complex medical needs often require extensive hospitalizations in the first years of life. Many of these children also experience complex communication needs and use augmentative and alternative communication (AAC) strategies to interact with health care staff. Unfortunately, suboptimal communication experiences have been reported among these children, their families, and hospital staff; however, no studies have described the patterns of interactions beyond measures of self-report. The purpose of this study was to describe child–parent–provider interaction patterns that occurred in an inpatient unit.

Method

Observational techniques were used to systematically describe the interactions of a 28-month-old child with complex communication needs, her parents, and 26 health care providers on an inpatient rehabilitation unit over 10 days.

Results

Results indicated that substantial variability in the child's routine occurred across days and providers. Interactions were generally short and occurred for only a small proportion of the child's waking hours. The child and her mother actively communicated to varying degrees across sessions, yet health care providers often dominated interactions. The child used multiple modes of communication in each interaction; however, no aided AAC systems were used despite availability.

Conclusions

Training is urgently required to equip health care providers to (a) incorporate the use of aided AAC strategies during inpatient interactions and (b) increase the active participation of both children with complex communication needs and their parents during these interactions.

Supplemental Material

https://doi.org/10.23641/asha.13345187
Down Syndrome and Autism Spectrum Disorder Dual Diagnosis: Important Considerations for Speech-Language Pathologists
Authors: Versaci Theresa M. , Mattie Laura J. , Imming Laura J.
Published: December 2020

Purpose

Individuals with Down syndrome (DS) often receive speech-language therapy services starting in infancy or toddlerhood. When providing speech-language therapy services for children with DS, speech-language pathologists (SLPs) need to consider the impact of other developmental and comorbid disorders that can affect language development, such as the presence of a dual diagnosis of DS and autism spectrum disorder (DS + ASD). The prevalence rate of ASD in DS is ~20%, which is higher than in the general population.

Method

This clinical focus article aims to provide SLPs with additional knowledge about DS + ASD to improve service delivery and support parents' ability to advocate for their child with confirmed or suspected DS + ASD. This is accomplished by summarizing the current evidence base on the presence of ASD in DS and discussing implications of a DS + ASD diagnosis for clinical practice with SLPs.

Conclusions

SLPs play a key role in supporting families of those with DS + ASD by advocating and educating. By understanding the unique profiles of strengths and weaknesses of individuals with DS + ASD, SLPs can provide appropriate service delivery (i.e., treatment and intervention approaches) and advocacy for their clients and their families.
Toward More Inclusive Gender Identity Measurement in Speech, Language, and Hearing Practice and Research
Authors: Merritt Brooke
Published: December 2020

Purpose

This article discusses current trends in clinical and research settings for collecting gender identity demographic information and argues for clinicians and researchers in communication disorders and sciences to adopt a two-question method for measuring the gender identity of clients and research participants. Traditional collection of gender demographic information has been constrained to a single question format with a binary response option. Increasing numbers of individuals across the life span identify with gender minorities such as transgender, nonbinary, and gender nonconforming, among others, and the traditional format for obtaining gender-identity related information is insufficient to capture and document this increasing diversity. An example of a two-question method for measuring gender identity demographic information is provided. The benefits and challenges of adopting such a measure in clinical and laboratory settings are discussed.

Conclusions

Gender minorities constitute a growing proportion of clinical caseloads and research participants within speech-language pathology and audiology. The adoption of demographic measurement tools that are inclusive of varying gender identities is necessary to acknowledge and quantify this growth and is a first step in normalizing transgender visibility in clinical and research settings. Such a move advances cultural responsiveness within the professions and promotes competent care and optimal health outcomes for individuals who are gender diverse.
Speech-Language Pathology and Audiology Care in the COVID-19 Era: Shared Experiences
Authors: Rule David W. , Karia Mathew K.
Published: December 2020

Purpose

The COVID-19 pandemic has rapidly altered the global health-care system and stretched scarce resources to the limit. Resource limitations include personal protective equipment and medical devices; however, limited resources also include the more valuable health-care professional. Recent focus has been on the acute management of COVID-19. Still, there is a need to focus on the long-term rehabilitation of patients moving out of the acute treatment phase and into survivorship due to chronic respiratory concerns and other COVID-19 complications. Multidisciplinary, collaborative teams will support positive outcomes. Thus, speech-language pathologists too must carefully consider their role in patient care during a global pandemic. What makes the COVID-19 pandemic unique is the rapid minimally mitigated spread of the disease from close contact to most regions of the world. However, what appears to be true is a collective experience and common bond across regional borders.

Conclusions

Perhaps, this global pandemic may lead to a global partnership, a shared experience, and mutually dependent relationships. Global health is no longer “international service” or something that happens “over there”; global health is our reality.
Average SER analysis of two‐hop WP DF relay system under κ−μ shadowed fading
Authors: Kumar Pawan , Dhaka Kalpana
Published: December 2020

This paper investigates the performance of a two‐hop decode‐and‐forward relaying system when the source node is energy‐constrained and it harnesses energy using the radio frequency signal radiated by the relay node. Data transmission at the energy‐constrained source node is enabled by the energy harvested at the node. The analysis is presented for two modulation schemes: coherent ‐ary phase‐shift keying and orthogonal non‐coherent ‐ary frequency‐shift keying. Analytical and asymptotic expressions for the average symbol error rate are derived for the considered modulation schemes under shadowed fading. The results are plotted to investigate the system's performance with variation in modulation order, fading parameters, and relay location.
Analysis of communication reliability in NarrowBand‐IoT oriented wireless sensor networks
Authors: He Xingyu , Liang Tingting , Zhang Zhao , Yang Guisong , Kong Linghe , Liu Ming
Published: December 2020

The unstable link quality in wireless sensor networks (WSNs) directly affects the success rate of data transmission. The retransmission mechanism is one of the commonly used methods to solve this problem. However, too many retransmissions could lower the communication efficiency. Therefore, to reduce retransmissions while guaranteeing the communication reliability in WSNs, this study introduces the NarrowBand Internet of Things (NB‐IoT) technology, and builds a network including both sensor and NB‐IoT nodes. The NB‐IoT node is designed to support both the radio frequency and the NarrowBand communication modes; thus it can communicate with both sensor nodes and NB‐IoT base stations. Further, the communication reliability metrics considering both the link quality and the number of retransmissions in different communication modes are defined, based on which, an adaptive communication reliability algorithm is proposed to switch the communication modes of nodes. The simulation results verify that the proposed algorithm can achieve higher success rate with less end‐to‐end delay and flexibly control the cost on NB‐IoT communication.
Secrecy performance of FSO communication systems with non‐zero boresight pointing errors
Authors: Verma Gyan Deep , Mathur Aashish , Ai Yun , Cheffena Michael
Published: December 2020

Free space optical (FSO) communication is a promising candidate for the next generation (5G and beyond) wireless communication systems, due to its merits (i.e. low latency, high data rate, and license‐free band, among others). However, atmospheric turbulence (AT) as well as pointing error (PE) are two of the main challenges with FSO communication that affect its performance. Here, the exact closed‐form expression of the average secrecy capacity and secrecy outage probability under the composite effect of AT and non‐zero boresight PEs is evaluated. For all the regimes of the AT (weak to strong), a generalised Malaga distribution is used to model the channel fading gain of the FSO link. The expressions are generalised and valid for all turbulence, and are applicable for intensity modulation direct detection as well as heterodyne detection techniques.
Convergence of an accelerated distributed optimisation algorithm over time‐varying directed networks
Authors: Hu Jinhui , Yan Yu , Li Huaqing , Wang Zheng , Xia Dawen , Guo Jing
Published: December 2020

In this article, studying distributed optimisation over time‐varying directed networks where a group of agents aims at cooperatively minimising a sum of local objective functions is focused on. Each agent uses only local computation and communication in the overall process without leaking their private information. Via incorporating both a distributed heavy‐ball method and a distributed Nesterov method, a double accelerated distributed algorithm leveraging a gradient‐tracking technique and using uncoordinated step‐sizes, is developed. By employing both row‐ and column‐stochastic weight matrices, the proposed algorithm can bypass the implementation of doubly stochastic weight matrices and avoid eigenvector estimation existing in some algorithms using only row‐ or column‐stochastic weight matrices. Under the assumptions that the agents' local objective functions are smooth and strongly convex, and the aggregated directed networks of every finite consecutive directed network are strongly connected, the proposed algorithm is proved to converge linearly to the global optimal solution when the largest step‐size is positive and sufficiently small, and the largest momentum parameter is non‐negative. The proposed algorithm is also applied to fixed directed networks which are considered as a special case of time‐varying directed networks. Simulation results further verify the effectiveness of the proposed algorithm and correctness of the theoretical findings.
A modified duty‐modulated predictive current control for permanent magnet synchronous motor drive
Authors: M L Parvathy , Eshwar Kusuma , Thippiripati Vinay Kumar
Published: December 2020

Predictive current control (PCC) is a promising technique for adjustable speed drives due to its intuitive features such as quick response, easy inclusion of non‐linearities and constraints as well as multi‐variable operation. The conventional predictive current control (C‐PCC) employs a cost function to choose the optimum vector, which reduces the error between the reference and the predicted current. Even though the C‐PCC can achieve excellent dynamic performance with a single active voltage, the steady‐state performance is affected with larger torque and flux ripples. When two voltage vectors are applied in a control interval, the steady‐state performance is improved. This paper proposes a modified duty‐based PCC for permanent magnet synchronous motor (PMSM) drives, employing an active and null vector in control interval, where the duration for which the optimal active vector is applied is based upon a simple error based calculation. The proposed duty calculation requires a simple constant and eliminates the need for current slope calculation, which results in parameter insensitive operation. The proposed method is compared with C‐PCC and recently published works based on duty calculation. The simulation and hardware experiments conducted on a PMSM drive confirm the effectiveness of the proposed method with reduced torque and flux ripples.
Study on noise and disturbance issues of generalized predictive speed control for permanent magnet synchronous machines
Authors: Wang Tao , Zhu Zi‐Qiang , Freire Nuno Miguel Amaral , Wu Zhanyuan , Foster Martin , Stone David A.
Published: December 2020

Generalized predictive control (GPC) is promising for permanent magnet synchronous machine drive systems, due to its outstanding dynamic performance and disturbance rejection capability. However, the speed measurement noise introduced by the encoder and the unmodelled disturbances introduced by the non‐ideal machine characteristics deteriorate the performance of GPC. The noise and disturbance issues are studied in detail, and an enhanced GPC method is proposed to address them. For the noise issue, the mathematical model of the speed measurement noise is derived, and the noise spectra at different speeds are analysed. Then, a novel GPC with internal low‐pass filter is proposed to reject the influence of the noise. For the disturbance issue, the influence of the unmodelled disturbances on the speed performance is assessed when applying different noise rejection methods, and a resonant controller‐based speed ripple mitigation method is proposed and integrated to the GPC. Experimental results show that the proposed methods can effectively deal with the noise and disturbance issues, as well as providing better dynamic performance than the conventional PI based speed control.
Multi‐stage coordinated operation of a multi‐energy microgrid with residential demand response under diverse uncertainties
Authors: Chen Yumin , Feng Xue , Li Zhengmao , Xu Yan , Miragha Amir
Published: December 2020

This paper presents a two‐stage stochastic operation method for a multi‐energy microgrid (MEMG). The method can optimally schedule distributed generators, electric boilers, electrical chillers, and storage devices under the system technical constraints. Various uncertainties from renewable energy generation, electricity tariff, and load demands are handled by this method. At the same time, the indoor temperature is controlled to guarantee the thermal comfort of customers. At the first stage, the unit commitment of all generators and charging/discharging power of energy storage devices are obtained. At the second stage, real‐time generation outputs from the generators are optimized given the uncertainty realization. The developed model is formulated as a mixed‐integer linear programming (MILP) problem with the objective of minimizing the daily operating cost. Several case studies are carried out to examine the effectiveness and performance of the proposed method. Simulation results show that the proposed method can effectively save the operational cost and, at the same time, maintain the robustness of the MEMG and customers’ thermal comfort.
Integration technology and practice for long‐distance offshore wind power in China
Authors: Pan Ersheng , Yue Bo , Li Xuan , Zhao Zheng , Zhu Quanle
Published: December 2020

Offshore wind power is an important kind of clean energy and of great development potential in the future. It has advantages of high wind speed and stable wind power, and gradually exhibits large‐scale, clustering, and long‐distance characteristics. Key technical problems of large‐capacity offshore wind power transmission over long distance must be solved in the development and utilization of offshore wind power, and will be addressed in this paper. First, this paper presents the overview of long‐distance offshore wind power integration in China, and then summarizes three types of integration schemes and its applicability. Second, it analyzes the characteristics of the voltage source converter based high voltage direct current (VSC‐HVDC) integration scheme and associated key technical problems in practice, and the first milestone long‐distance offshore wind power integration VSC‐HVDC project in China is then introduced. Finally, recommendations on long‐distance offshore wind power development in China are presented based on the characteristics of long‐distance offshore wind power and VSC‐HVDC integration technology.
A novel MILP‐Newton approach for power flow analysis
Authors: Silva Diego Nunes da , Pereira Júnior Benvindo Rodrigues , Costa Geraldo Roberto Martins da
Published: December 2020

This paper presents a novel mixed integer linear programming‐Newton approach for solving constrained AC power flow problems, based on a recently proposed linear programing‐Newton method. The linear programming‐Newton method overcomes some deficiencies of the classical Newton's method, while retaining its quadratic convergence in the neighbourhood of a solution. The discrete nature of some control variables, such as transformer tap ratios and bus shunt susceptances, are often ignored in power flow algorithms due to difficulties that they introduce. The violation of operational limits in power flow algorithms is typically corrected in ex‐post procedures, such as PV‐PQ bus switching, which may lead to infeasibilities. Finally, under some circumstances, power flow problems may not have a solution; in these cases, a desirable property of a power flow algorithm would be the ability to obtain a nearly feasible solution. The approach proposed in this paper handles these difficulties in a unified framework and is able to deal directly with discrete variables and operational limits. When there are no power flow solutions, a nearly feasible solution that minimizes a merit function is obtained. Numerical experiments show that the proposed approach is robust and obtains accurate solutions in the presence of discreteness conditions and operational limits.
Islanding detection in photovoltaic based DC micro grid using adaptive variational mode decomposition and detrended fluctuation analysis
Authors: Eluri Naga Venkata Durga Vara Prasad , Dash Pradipta Kishore , Dhar Snehamoy
Published: December 2020

This study presents a novel approach using adaptive variational mode decomposition with detrended fluctuation analysis to detect the islanding disturbances for photovoltaic based DC micro grid. DC parameters are simple to estimate in comparison to AC profile. Thus DC parameters are recorded under islanding scenario, and processed through proposed adaptive variational mode decomposition which decomposes the signals into intrinsic mode functions. These segregated intrinsic mode functions are further selected optimally by choosing the significant weighted kurtosis index. This optimal selection (maximisation of weighted kurtosis index) is ensured by modified particle swarm optimisation in terms of number of modes (K) and penalty factor (σ). For detection and monitoring (D&M) accurate islanding scenario the significant intrinsic mode functions are subjected to detrended fluctuation analysis, where power exponent (α) values are utilised for correct detection (i.e. distinguishing islanding out of other grid contingencies by two and three dimensional scattering plots). The effectiveness of the proposed D&M for DC micro grid is established in this paper in terms of classification accuracy and relative computational time. The proposed DC side islanding D&M method is less complex (as compared to AC signals) to be implemented. Fastness and accuracy of proposed D&M is established and performed in MATLAB/Simulink platforms.
Data‐driven power system linear model identification for selective modal analysis by frequency interpolations
Authors: Zelaya‐A. Francisco , Chow Joe H. , Arrieta Paternina Mario. R. , Zamora‐Mendez Alejandro
Published: December 2020

This paper proposes a new approach to identify a data‐based power system linear model by means of frequency interpolations, aiming to obtain a suitable system representation for selective‐modal analysis purposes. The key idea behind the identification process is the Loewner‐based frequency interpolation carried out by the Loewner matrices. The proposed approach demonstrates that the Loewner‐based frequency interpolation is able to fit a linear model that can be used for small‐signal analysis studies, since it provides the state‐space representation, the frequency response, and modal information (frequency, damping, and mode‐shape). Then, a selective modal analysis is accomplished over two test cases (Kundur and New England–New York power grids) by employing the identified linear model provided by the Loewner‐based frequency interpolation method. The attained results confirm the outstanding performance of the proposal which is validated against the small‐signal analysis and compared with the eigensystem realisation algorithm, overcoming the absolute error of the model identified with the traditional eigensystem realisation algorithm approach by at least 37 times, and properly capturing the modal information in a frequency band of concern.
Effect of magnetic field on double layer in argon helicon plasma
Authors: Yang Kaiyi , Cui Ruilin , Zhu Wanying , Wu Zhiwen , Ouyang Jiting
Published: December 2020

The electric double layer in argon helicon plasma by using floating electrostatic probe and local optical emission spectroscopy under different external magnetic field was investigated. Results show that electrons generated in the plasma source can be magnetized by the magnetic field and transported by the gradient of diverging magnetic field in the diffusion chamber, giving rise to the hollowed distribution of electron temperature. The electron temperature on axis has a sudden decrease, leading to the sudden decrease of plasma density as well as the plasma potential, forming a double layer structure. The position of double layer moves along with the position of diverging magnetic field, and the potential drop increases along with the strength of magnetic field. The structure of the external magnetic field plays the decisive factor for the double layer in helicon plasma.
Space charge dynamics in epoxy resin under voltage polarity reversal at various temperatures
Authors: Liu Peng , Zhang Hongliang , Zhang Siyu , Su Xialin , Xie Zongliang , Peng Zongren
Published: December 2020

Epoxy resin has been used to cast the core of the dry‐type high voltage direct current bushings and can accumulate space charge under high electric fields at high temperatures, which is believed to be a potential threat to the safe operation of dry bushings, especially under polarity reversal. In this study, results of a study of the evolution of space charge and electric field distribution in epoxy resin, under polarity reversal at 10 and 20 kV/mm, and at temperatures between 40 and 100°C, are presented. The results show that the space charge dynamics in epoxy resin during the test were different at various temperatures. At temperatures no more than 60°C, space charge accumulation within the samples was not obvious. Instead, a low‐frequency dielectric relaxation process maybe occurs during the polarity reversal, which made the charge peaks on the electrodes after the reversal were slightly smaller than those before the reversal. At temperatures no less than 80°C, considering that the applied electric field has little effect on the barrier reductions of the traps within the samples, the space charge dynamics were mainly governed by a thermally activated process, and the depths of the deepest occupied traps were obtain by analysing the transient processes.
Characterization of magnetic field waveforms from triggered lightning attached on transmission line at 18 m, 130 m and 1.55 km
Authors: Cai Li , Li Jin , Wang Jianguo , Zhou Mi , Li Quanxin , Fan Yadong
Published: December 2020

The authors present a statistical analysis of characteristics of magnetic fields at different distances from triggered lightning experiments on Transmission Line at Guangdong Comprehensive Observation Experiment on Lightning Discharge during the summer of 2019. The histograms and parameters of statistical distributions for the following 22 waveform characteristics are presented, including current peak, 10%–90% risetime, half‐peak width and steepness, leader magnetic field peak, return‐stroke magnetic field peak, magnetic field peak, 10%–90% risetime, half‐peak width and steepness at 15 m, 130 m and 1.55 km. The arithmetic mean of 48 return stroke current peaks is 18.3 kA and the geometric mean is 17.0 kA. The arithmetic and geometric means of the current 10%–90% risetime are 0.6 and 0.6 μs, respectively. The leader magnetic field, return‐stroke magnetic field and magnetic field peak at 18 m, 130 m and 1.55 km are shown linear relationship with current peak values. With increasing the distance(r), the magnetic field peak value decrease, combining the magnetic field characteristics reported by previous studies, the analysis of all magnetic field peaks in different distances suggest linear relationship with r
−0.90. The magnetic field 10%–90% risetime shows linear relationship with ln(r) and half‐peak width did not show significant correlation with distance.
Research on 3‐D total electric field of crossing high voltage direct current transmission lines based on upstream finite element method
Authors: Ma Xiaoqian , Xie Li , He Kun , Lu Jiayu
Published: December 2020

The ongoing large‐scale construction of ultra high voltage direct current projects in China makes the crossing of two high voltage direct current (HVDC) lines inevitable. It is critical to study the characteristics and calculation method of 3‐D total electric fields of crossing HVDC lines. The problems encountered when applying the 3‐D upstream finite element method to calculate total electric field of crossing HVDC lines and the solutions are studied in this study. In view of the surface electric field varying greatly along longitudinal direction of conductors, the calculation method adopting the Davidon‐Fletcher‐Powell optimization algorithm is introduced to realize the fast computation of 3‐D space‐charge‐free field. Considering the distinct corona intensity at different positions of conductors, a new formula for initializing charge density is studied to ensure the convergence of calculation process. Considering the large computation amount of total electric field, an adaptive iteration strategy is put forward to effectively speed up the calculation. The measurement of ground total electric field underneath a crossing HVDC test line is conducted to verify the validity of the proposed calculation method. The distribution characteristics of electric fields of crossing HVDC lines are calculated and analysed. The research results will provide technical support for the design and environmental impact assessment of crossing HVDC transmission lines.
Spatially continuous transformer online temperature monitoring based on distributed optical fibre sensing technology
Authors: Liu Yunpeng , Li Xinye , Li Huan , Yin Junyi , Wang Jiaxue , Fan Xiaozhou
Published: December 2020

Transformer internal thermal monitoring exists huge blind areas, and it is difficult for traditional methods to get fully distributed temperature in real time. In this contribution, the distributed optical fibre sensor was creatively applied inside an operating 35 kV oil‐immersed transformer which is also qualified for actual power grid operation through the ex‐factory tests. Furthermore, the full‐region temperature along the windings and iron limbs were firstly monitored in a spatiotemporally continuous manner and the hotspots were also closely traced, fluctuating at 90% of the high‐voltage winding height (80% for low‐voltage winding) during the whole process of the heat‐run test. Corresponding Finite Element Method (FEM) for thermo‐fluid field calculation was then utilized for deeper analysis. On the former basis, the actual detected temperature distributions (both spatial and temporal) were compared with the International Electrotechnical Commission traditional model and some modifications were suggested based on the real time measured data. This novel online monitoring application and the detailed internal thermal information may provide a solid reference for the delicate management of power transformers, which also offers a new horizon for the online monitoring in electrical apparatus industry.
On the charged aerosols generated by atmospheric pressure non‐equilibrium plasma
Authors: Zhang Yanzhe , Cheng He , Gao Haotian , Liu Dawei , Lu Xinpei
Published: December 2020

Recently, charged aerosols are used widely in many applications, such as fog elimination, inactivation of airborne viruses and so on. Atmospheric pressure non‐equilibrium plasma (APNP) have become an efficient way to generate charged aerosols. Except the traditional pin‐plate or wire‐plate APNP sources, the new APNP sources such as large scale corona discharge system and air plasma jet array are introduced. These sources can increase the ion density in open air and generate adjustable large plasma plume, which are helpful in increasing the charging efficiency on aerosols. Although the interactions between plasma and aerosols is quite complicated, the preliminary study suggests that the diffusion charging dominates aerosols below 0.1 μm, field charging dominates aerosols larger than 1 μm, and the photo charging also contributes to aerosols charging. These reactive charged aerosols have shown their potential in the artificial rain enhancement, biomedicine, and material processing. Finally, challenges and opportunities for theoretical, experimental, and application research in related cross‐disciplinary areas are presented to stimulate critical discussions and collaborations in the future.