bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stability analysis of sub‐synchronous oscillation in power system connected with virtual synchronous DFIGs
Authors: Ma Jing , Xu Honglu , Li Pengchong , Cheng Peng 
Published: October 2021

AbstractConcerning sub‐synchronous oscillation in power system connected with virtual synchronous DFIGs, an oscillatory stability analysis method based on the dissipation rate of dynamic energy is proposed. First, the dynamic energy function that reflects the sub‐synchronous oscillation characteristics of virtual synchronous DFIG is built, and the expression of dynamic energy considering virtual synchronous control parameters is analysed. Then, according to Lyapunov's stability law, the variation rate of dynamic energy function is defined as the energy dissipation rate. The energy dissipation rate reflects the variation trend of system dynamic energy during oscillation, thus it is used as the stability criterion of sub‐synchronous oscillation. On this basis, the effects of different virtual synchronous control parameters on sub‐synchronous oscillation are analysed for a comprehensive consideration of system stability. Finally, simulation tests are conducted on RT‐LAB platform. The results verify that, when the energy dissipation rate is positive, system oscillation diverges; when the energy dissipation rate is negative, system oscillation converges. Meanwhile, the larger the virtual resistance is, the worse the stability of system is; the larger PI control parameters of reactive power control loop are, the worse the stability of system is.
A novel control approach for harmonic compensation using switched power filter compensators in micro‐grids
Authors: Khosravi Nima , Abdolmohammadi Hamid Reza , Bagheri Sajad , Miveh Mohammad Reza 
Published: October 2021

AbstractThis paper presents a new harmonic compensation system using filter compensator devices in a hybrid micro‐grid (MG). In order to reduce the amplitude of current and voltage harmonics, two separate systems, including a switched power filter compensator (SPFC) and a switched active power filter (SAPF) have been used in the AC side of the MG. The gain coefficients of both SAPF and SPFC modules (with different controllers) using meta‐heuristic algorithms are optimized and applied for three harmonic loops of voltage, current and controller error to obtain an optimal response for reducing the harmonic amplitude of current and voltage. The objective function, containing controller error, current and voltage harmonics is defined and followed by the optimized coefficients for the PID controller of each of the SAPF and SPFC modules. To find the best answer to this problem, the related gains using four meta‐heuristic algorithms, including artificial bee colony (ABC), particle swarm optimization (PSO), harmonic search (HS), and differential evolution (DE) are optimized and compared. The simulation results show that using the proposed method, the total harmonic distortion of the system can be significantly reduced.
Floating offshore wind turbine fault diagnosis via regularized dynamic canonical correlation and fisher discriminant analysis
Authors: Wu Ping , Liu Yichao , Ferrari Riccardo M.G. , van Wingerden Jan‐Willem 
Published: October 2021

AbstractOver the past decades, Floating Offshore Wind Turbine (FOWT) has gained increasing attention in wind engineering due to the rapidly growing energy demands. However, difficulties in turbine maintenance will increase due to the harsh operational conditions. Fault diagnosis techniques play a crucial role to enhance the reliability of FOWTs and reduce the cost of offshore wind energy. In this paper, a novel data‐driven fault diagnosis method using regularized dynamic canonical correlation analysis (RDCCA) and Fisher discriminant analysis (FDA) is proposed for FOWTs. Specifically, to overcome the collinearity problem that exists in measured process data, dynamic canonical correlation analysis with a regularization scheme, is developed to exploit the relationship between input and output signals. Then, the residual signals are generated from the established RDCCA model for fault detection. To further classify the fault type, an FDA model is trained from the residual signals of different training faulty data sets. Simulations on a FOWT baseline model based on the widely used National Renewable Energy Laboratory FAST simulator are carried out to demonstrate the feasibility and efficacy of the proposed fault detection and classification method. Results have shown many salient features of the proposed method with potential applications in FOWTs.
Forward modelling of heating within a coronal arcade
Authors: Fyfe L. E. , Howson T. A. , De Moortel I. 
Published: October 2021

Aims. We investigate the synthetic observational signatures generated from numerical models of coronal heating in an arcade in order to determine what features are associated with such heating and what tools can be used to identify them.
Methods. We consider two simulations of coronal arcades driven by footpoint motions with different characteristic timescales. Forward modelling is then conducted, and the synthetic emission data are analysed (e.g., intensities, Doppler shifts, line widths and estimated kinetic energies).
Results. The total intensity and Doppler shift perturbations clearly show the magnetic structure of the coronal arcade. Contrasts in the local Doppler velocity also highlight the locations of separatrix surfaces. The distinguishing feature of the models with short and long timescale photospheric motions (in comparison to the Alfvén travel time along a loop) is that of the frequencies. Through fast Fourier transform analysis of the Doppler velocities, it is clear that when short timescale footpoint motions are present, higher frequency perturbations are observed. For longer timescale footpoint motions, the dominant signal is that of lower frequencies; however, higher (but less powerful) frequencies were also detected, which matched the natural Alfvén frequency of the background magnetic field. Signatures of Alfvénic waves were identified in both models, with fast wave signatures observable when short timescale driving is present. Finally, we examine the estimates of the kinetic energy using the Doppler velocities and find it to be significantly underestimated within these models.
Conclusions. All of the observables within this article behave as one would expect, given the evolution of the plasma parameters. Such features were, for example, Alfvén waves, fast waves, the arcade structure and separatrix surfaces. We were able to differentiate between the two models by examining the frequencies present. The Doppler velocities cannot provide accurate estimates of the total kinetic energy or even the component parallel to the line-of-sight (LOS). This is due to some of the plasma being outside the formation temperature of the ion, the multi-directional driver limiting the proportion of the velocity aligned along the LOS, and cancellation of the velocity along the LOS. The exact impact each factor has on the estimation is dependent on the setup of the model and the emission line under investigation.
EMISSA (Exploring Millimeter Indicators of Solar-Stellar Activity)
Authors: Mohan A. , Wedemeyer S. , Pandit S. , Saberi M. , Hauschildt P. H. 
Published: October 2021

Context. Due to their wide wavelength coverage across the millimeter to centimeter (mm–cm) range and their increased sensitivity, modern interferometric arrays facilitate observations of the thermal and non-thermal radiation that is emitted from different layers in the outer atmospheres of stars.
Aims. We study the spectral energy distribution (Sobs(ν)) of main-sequence stars based on archival observations in the mm–cm range with the aim to study their atmospheric stratification as a function of stellar type.
Methods. The main-sequence stars with significant detection in mm bands were identified in the ALMA Science Archive. These data were then complemented with spectral flux data in the extreme ultraviolet to cm range as compiled from various catalogues and observatory archives. We compared the resultant Sobs(ν) of each star with a photospheric emission model (Smod(ν)) calculated with the PHOENIX code. The departures of Sobs(ν) from Smod(ν) were quantified in terms of a spectral flux excess parameter (ΔS∕Smod) and studied as a function of stellar type.
Results. The initial sample consists of 12 main-sequence stars across a broad range of spectral types from A1 to M3.5 and the Sun-as-a-star as reference. The stars with Teff = 3000–7000 K (F–M type) showed a systematically higher Sobs(ν) than Smod(ν) in the mm–cm range. Their ΔS∕Smod exhibits a monotonic rise with decreasing frequency. The steepness of this rise is higher for cooler stars in the Teff = 3000–7000 K range, although the single fully convective star (Teff ~ 3000 K) in the sample deviates from this trend. Meanwhile, Sobs(ν) of the A-type stars agrees with Smod(ν) within errors.
Conclusions. The systematically high ΔS∕Smod in F–M stars indicates hotter upper atmospheric layers, that is, a chromosphere and corona in these stars, like for the Sun. The mm–cm ΔS∕Smod spectrum offers a way to estimate the efficiency of the heating mechanisms across various outer atmospheric layers in main-sequence stars, and thereby to understand their structure and activity. We emphasise the need for dedicated surveys of main-sequence stars in the mm–cm range.
Anticipate, Target and Characterize: MS²-anticipated
C-glycosylflavones from Erythrococca anomala
Authors: Kouamé Tapé , Okpekon Timothée , Bony Nicaise F. , Ferron Solenn , Bonnaffé David , Vanheuverzwijn Jérôme , Zhou Zhiyu , Fontaine Véronique , N’Tamon Amon Diane , Gallard Jean-François , Leblanc Karine , Jullian Jean-Christophe , Miel Corto , Champy Pierre , Beniddir Mehdi A. , Le Pogam Pierre 
Published: October 2021

AbstractWe herein report on the first chemical assessment of Erythrococca anomala
(Juss. ex Poir.) Prain (Euphorbiaceae), a genus that was – to the best
of our knowledge – not studied yet from a phytochemical perspective. A
molecular networking strategy was implemented to rapidly identify the known
specialized metabolites from untargeted MS/MS analyses of E.
anomala leaves ethanolic extract. This strategy allowed for the
identification of diverse C-glycosyl flavones and a cursory examination
of MS/MS spectra could extend the GNPS-provided annotation to pinpoint
the structural novelty of further derivatives. The isolation of the sought-after
structures could be streamlined based on MS-guidance and their structures,
determined through extensive NMR analyses, displayed structural features in line
with MS²-based predictions. Anticipating sharp structural features at an
early stage of the dereplication process through a critical assessment of the
tandem mass spectrometric landmarks was essential to embark on the isolation of
the newly reported structures owing to the elevated number of flavonoid
glycosides isomers thereof formerly known, which would have deterred us from
isolating them without the support of additional tandem mass spectrometric
information. The isolation of the main components of the ethanolic extract
completed the currently provided chemical report on E. anomala, also
resulting in the description of a new phenylethanoid derivative (3) and
of a new orcinol-based dimer (4). Anomaloflavone (1) exhibit
significant activities with minimal inhibitory concentration values of
25 µg/mL against Staphylococcus aureus and
Mycobacterium smegmatis while failing to exert an antibacterial
activity against Pseudomonas aeruginosa, while being devoid of
cytotoxicity against SiHa cells.
The Chimney/Periscope Technique as Total Endovascular Treatment of Kommerell's Diverticulum
Authors: Zavatta Marco , Squizzato Francesco , Dall'Antonia Alberto , Piazza Michele , Antonello Michele 
Published: October 2021

AbstractWe report a case of Kommerell's diverticulum (KD) treated with a total endovascular approach, maintaining supra-aortic trunk (SAT) patency. A 75 year-old female with aneurysmal KD was deemed unsuitable for open surgery. Landing zone 2 was unfeasible; therefore, we planned an endovascular approach with landing in zone 1, chimney to left subclavian artery and periscope to right subclavian artery. Postoperatively she was free from complications, with complete exclusion of KD and SAT patency at 3-year follow-up.
Electroencephalogram Abnormalities and Epilepsy in Autism Spectrum Disorders: Clinical and Electroencephalogram Findings
Authors: Hanci Fatma , Türay Sevim , Öztürk Yusuf , Kabakus Nimet 
Published: October 2021

AbstractIt has been known for several decades that epilepsy and autism spectrum disorders (ASD) are related to each other. Epilepsy frequently accompanies ASD. The purpose of this study was to investigate relationship between clinical and electroencephalogram (EEG) findings in ASD patients and to identify EEG characteristics that may create a disposition to epilepsy in ASD by examining differences in clinical and EEG findings between patients diagnosed with ASD without epilepsy and ASD with epilepsy. A total of 102 patients aged 2 to 18 years and diagnosed with ASD based on Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5) diagnostic criteria between January 2017 and June 2019 were included in the study. Patients were assigned into two groups: (1) ASD with epilepsy and (2) ASD without epilepsy. Clinical findings were retrieved from patients' files, and EEG findings from first EEG records in the EEG laboratory at the time of diagnosis. EEG findings were defined as central, parietal, frontal, temporal, or generalized, depending on the location of rhythmic discharges. The incidence of epilepsy in our ASD patients was 33.7% and that of febrile convulsion was 4%. Generalized motor seizures were the most common seizure type. Epileptic discharges most commonly derived from the central and frontal regions. These abnormalities, especially frontal and central rhythmic discharges, may represent a precursor for the development of epilepsy in ASD patients.
Torticollis as an Initial Manifestation of a Seronegative Demyelinating Disorder in a Child: A Case Report
Authors: Kini Sandesh , Yellanthoor Ramesh Bhat , Karegowda Lakshmikanth Halegubbi 
Published: October 2021

AbstractTorticollis refers to a condition in which the head is persistently tilted to one side, sometimes associated with pain. Torticollis in a child can be congenital or acquired. Torticollis as an initial manifestation of an underlying demyelinating syndrome is quite rare in children. Here, we report a 7-year-old girl who presented with persistent torticollis. Neuroimaging of the brain revealed features of a demyelinating disease. Further studies did not show any evidence of multiple sclerosis. Cerebrospinal fluid was negative for antiaquaporin-4 antibodies, antimyelin oligodendrocyte glycoprotein antibodies, and oligoclonal bands. A seronegative demyelinating disorder was considered. She was treated with pulsed methylprednisolone therapy. She responded well to steroids with no progression of illness during follow-up. Torticollis was partially improved.
A Rare Case of Acute Hemorrhagic Leukoencephalitis in a Neonate
Authors: Gupta Nishu , Jindal Gunjan , Singla Hanish 
Published: October 2021

AbstractAcute hemorrhagic leukoencephalitis (AHLE) is a fulminant demyelinating disease associated with severe inflammation of the white matter. In this article, we reported a case of previously healthy 27 days old baby admitted to the hospital with fever, excessive crying, seizures, and respiratory distress. A diagnosis of AHLE was made based on the clinical and radiological findings. The infant patient was managed in the neonatal intensive care unit; however, he died unfortunately on the 35th day of his life. Although this highly fatal disease is very rare in this age group, early diagnosis can help in reducing morbidity and mortality.
Growth Pattern and Use of Inter-pupillary Distance in the Detection of Ocular Hypertelorism and Hypotelorism in Indian Down Syndrome Children
Authors: Bhalla Anil Kumar , Kaur Harvinder , Kaur Rupinder , Panigrahi Inusha , Walia Brij Nandan Singh 
Published: October 2021

AbstractUse of inter-pupillary distance (IPD) for objective evaluation of ocular hypertelorism and hypotelorism is recommended to corroborate diagnosis of syndromic conditions. In view of complete absence of serial data on growth of IPD, this study aims to unfold auxological dynamics of IPD in Down syndrome (DS) children of Indian origin. Inner canthal distance (ICD) and outer canthal distance (OCD) were measured on a total of 1,125 (male: 752, female: 373) DS children, aged 0 to 3 months to 10 years at 6 monthly age intervals using a “Digimatic Sliding Caliper” in the Growth Laboratory/Growth Clinic of the Institute. Using Feingold and Bossert (1974) formula, IPD at each age was calculated from ICD and OCD measured among male and female DS children. IPD, like OCD and ICD increased un-interruptedly among DS children. IPD grew rapidly up to 5 years thereafter, its rapidity became slower. Boys in general, possessed larger IPD than girls, however, gender differences became statistically significant up to first 4 years of life. Our study children possessed significantly smaller IPD as compared with their normal Indian counterparts. None of our DS children depicted ocular hypertelorism while hypotelorism, was noticed amongst 4.9% male and 16.8% female DS patients. Comparison with normative IPD data failed to establish existence of ocular hypertelorism in DS children (<10 years) of north-western Indian origin. Use of age and gender-specific data presented for IPD of DS children may be made for comparative purpose to ascertain inter-population variability.
The pregnancy drop: How teaching evaluations penalize pregnant faculty
Authors: Olabisi Ronke M. 
Published: October 2021

AbstractThe “leaky pipeline” and the “maternal wall” have for decades described the loss of women in STEM and the barriers faced by working mothers. Of the studies examining the impact of motherhood or pregnancy on faculty in higher education, most focus on colleagues’ attitudes towards mothers; few studies explore pregnancy specifically, only a handful examine student evaluations in particular, and none include female faculty in engineering. This study is the first to compare student evaluations across fields from female faculty when they were pregnant against when they were not. Two scenarios were considered: (1) the lived experiences of faculty who taught classes while pregnant and while not pregnant and (2) an experiment in which students submitted teaching evaluations for an actress whom half the students believed was pregnant while the other half did not. Among faculty respondents, women of colour received lower scores while pregnant and these scores lowered further when women were in engineering and/or had severe symptoms. Depending on their demographics, students who participated in the experiment were awarded teaching evaluation scores that differed when they believed the instructor was pregnant. Findings suggest that in fields with fewer women, the maternal wall is amplified and there is a unique intersectional experience of it during pregnancy. These findings may be useful for Tenure and Promotion committees to understand and therefore account for pregnancy bias in teaching evaluations.
Cost-effectiveness in health: consolidated research and contemporary challenges
Authors: dos Santos Silva Eric Kaun , Cruz June Alisson Westarb , da Cunha Maria Alexandra Viegas Cortez , de Moraes Thyago Proença , Marques Sandro , da Silva Eduardo Damião 
Published: October 2021

AbstractThe need to develop alternatives to improve health assistance access and qualification was emergent and urgent even before the advent of Covid-19. Such demand is necessary in regard to both public and private systems. In this context, the theme of cost and effectiveness is technically adequate and viable to analyze these alternatives. Analyzing the history of research development on the topic and identifying its gaps is thus an essential step in facing this challenge. Therefore, the objective of this study was to modestly contribute to a bibliometric examination of scientific production based on the theme of cost-effectiveness to guide future research, despite the maturity of the theme, and as well as its future challenges. As a result, several essential aspects of the theoretical approach to the theme were observed, such as its conceptualization, purpose, and objective within public and private institutions, identifying its main authors, universities, reference countries, and funding institutions, authors’ relationship networks, and related themes. One of the most important factors identified is the absence of the theme applied to contemporary topics in health, such as telemedicine, telehealth, robotics, artificial intelligence, new drugs and medicines, and new healthcare protocols.
Mammalian sperm hyperactivation regulates navigation via physical boundaries and promotes pseudo-chemotaxis
Authors: Zaferani Meisam , Suarez Susan S. , Abbaspourrad Alireza 
Published: October 2021

Significance
Mammalian sperm migration within the female reproductive tract requires navigational mechanisms, through which sperm respond to biophysical and biochemical cues. Previous studies revealed that biophysical cues for sperm in the female reproductive tract include fluid flow, wall architecture, and temperature gradients. Here, by exploring bovine sperm motion in microfluidic reservoirs and by developing theoretical and computational models, we demonstrate that sperm motility hyperactivation, which is part of a process that prepares sperm in the female tract for fertilization and involves an increase in the asymmetry of sperm flagellar beating, modulates sperm–sidewall interactions and thus navigation via female tract wall architecture. Specifically, hyperactivation reduces the tendency of sperm to remain swimming along walls and promotes a response that resembles chemotaxis.
Kinetic proofreading of lipochitooligosaccharides determines signal activation of symbiotic plant receptors
Authors: Gysel Kira , Laursen Mette , Thygesen Mikkel B. , Lironi Damiano , Bozsóki Zoltán , Hjuler Christian T. , Maolanon Nicolai N. , Cheng Jeryl , Bjørk Peter K. , Vinther Maria , Madsen Lene H. , Rübsam Henriette , Muszyński Artur , Ghodrati Arshia , Azadi Parastoo , Sullivan John T. , Ronson Clive W. , Jensen Knud J. , Blaise Mickaël , Radutoiu Simona , Stougaard Jens , Andersen Kasper R. 
Published: October 2021

Significance
Plant cell surface receptors perceive carbohydrate signaling molecules and hereby establish communication with surrounding microbes. Genetic studies have identified two different classes of lysin motif receptor kinases as gatekeepers that together trigger the symbiotic pathway in plants; however, no structural or functional data of the perception mechanisms switching these receptors from resting state into activation is known. In this study, we use structural biology, biochemical, and genetic approaches to demonstrate how the NFP/NFR5 class of lipochitooligosaccharide (LCO) receptors discriminate bacterial symbionts based on a kinetic proofreading mechanism that controls receptor activation and signaling specificity. We show that the LCO binding site can be engineered to support symbiotic functions, which greatly advance future opportunities for receptor engineering in legumes and nonlegumes.