bluuebunny/crossref_metadata_2025_split huggingface dataset:
Research on the dynamic characteristics of electric field distribution of the ± 1100 kV Ultra high voltage converter transformer valve‐side bushing using weakly ionised gas conductance model
Authors: Wang Qingyu , Liu Peng , Tian Huidong , Xie Gengsheng , Peng Zongren , Yang Xi 
Published: December 2020

AbstractUltra high voltage (UHV) converter transformer valve‐side bushings are the key equipment indirect current (DC) transmission projects, and are subjected to high voltage and large current with large number of harmonics simultaneously. The electric field distribution of converter transformer valve‐side bushings is time‐dependent under DC voltage, polarity reversal voltage and actual voltage waveforms, and the electric and temperature field are coupling with each other in actual operation. The dynamic characteristics of the surface charges and the electric field distribution of China's first ± 1100 kV epoxy/paper – SF6 composite insulation converter trans former valve‐side bushing under 2 h DC withstand test voltage and polarity reversal voltage were analysed considering the natural ionisation, drifting, diffusion and recombination processes of positive and negative ions in SF6 gas and air. The time‐dependent electro‐thermal coupling field of the bushing under the actual voltage waveform in one cycle was obtained. The rationality of the simulation method adopted was verified through type tests of the UHV converter transformer valve‐side bushing. The simulation results of the paper can provide a theoretical foundation for the design of converter transformer valve‐side bushings and it is of great significance to ensure the safe operation of converter stations.
Improving the RSM map exoplanet detection algorithm
Authors: Dahlqvist C.-H. , Louppe G. , Absil O. 
Published: December 2020

Context. High-contrast imaging is one of the most challenging techniques for exoplanet detection. It relies on sophisticated data processing to reach high contrasts at small angular separations. Most data processing techniques of this type are based on the angular differential imaging observing strategy to perform the subtraction of a reference point spread function (PSF). In addition, such techniques generally make use of signal-to-noise (S/N) maps to infer the existence of planetary signals via thresholding.
Aims. An alternative method for generating the final detection map was recently proposed with the regime-switching model (RSM) map, which uses a regime-switching framework to generate a probability map based on cubes of residuals generated by different PSF subtraction techniques. In this paper, we present several improvements to the original RSM map, focusing on novel PSF subtraction techniques and their optimal combinations, as well as a new procedure for estimating the probabilities involved.
Methods. We started by implementing two forward-model versions of the RSM map algorithm based on the LOCI and KLIP PSF subtraction techniques. We then addressed the question of optimally selecting the PSF subtraction techniques to optimise the overall performance of the RSM map. A new forward-backward approach was also implemented to take into account both past and future observations to compute the RSM map probabilities, leading to improved precision in terms of astrometry and lowering the background speckle noise.
Results. We tested the ability of these various improvements to increase the performance of the RSM map based on data sets obtained with three different instruments: VLT/NACO, VLT/SPHERE, and LBT/LMIRCam via a computation of receiver operating characteristic curves. These results demonstrate the benefits of these proposed improvements. Finally, we present a new framework to generate contrast curves based on probability maps. The contrast curves highlight the higher performance of the RSM map compared to a standard S/N map at small angular separations.
Frakturen der Wirbelsäule bei Morbus Bechterew
Authors: Heyde Christoph-Eckhard , Völker Anna , von der Höh Nicolas Heinz 
Published: December 2020

ZUSAMMENFASSUNGFrakturen der Wirbelsäule bei M. Bechterew bedürfen einer aufmerksamen Diagnostik und der Berücksichtigung spezieller perioperativer und operativer Besonderheiten. Die Grundkrankheit führt zu ausgeprägten biologischen und biomechanischen Veränderungen der Wirbelsäule. Daraus resultiert eine erhöhte Vulnerabilität gegenüber Traumata, insbesondere auch sogenannter Bagatelltraumata. Dies führt sowohl zu einer erhöhten Rate an Wirbelsäulenverletzungen als auch zu einer erhöhten Rate primärer und sekundärer neurologischer Komplikationen. Die Diagnostik umfasst grundsätzlich eine dezidierte Abklärung der gesamten spinalen Achse. Die perioperative Therapie muss den Besonderheiten der Grundkrankheit angepasst werden. Die in aller Regel operative Frakturversorgung kann anspruchsvoll sein. Somit erfordert die Diagnostik und Therapie von Verletzungen der Wirbelsäule bei M. Bechterew chirurgische Erfahrung und gute Kenntnisse der aus der Grundkrankheit resultierenden Besonderheiten dieser Patienten.
Fast Motion Speed Alters the Sit-to-Walk Spatial and Temporal Pattern in Healthy Young Men
Authors: Rousanoglou Elissavet N. , Kondilopoulos Nikolaos , Boudolos Konstantinos D. 
Published: December 2020

AbstractSit-to-Walk (STW) is a critical task for daily independence, yet its two inherent destabilizing events (seat-off, walking initiation) may diminish postural stability under fast motion speed (FS). This study aimed at the FS effect on the STW spatial and temporal patterns, with a specific interest in the relative STW temporal pattern. The STW kinetics and kinematics were recorded (n=18 men, 20.7±2.0 years) at preferred and FS. Statistics included One-Way repeated measures ANOVA (SPSS 25.0, p≤0.05). The FS spatial pattern reveals a discontinuous mode of the forward ground reaction force, indicating a balance rather than a propulsive strategy during the Rising phase. The FS relative temporal pattern reveals the prolongation of the Leaning phase (most possibly due to the feet repositioning), the shortening of the Rising and the Walking phases, and a relative delay in the spatial variables (p≤0.05). Overall, the results do not allow the STW consideration at FS as a “magnified” with respect to force, or a “shrinked-in” with respect to time, copy of the preferred motion speed. As more generic and versatile than the absolute one, the relative temporal pattern may be used as a reference for a variety of populations.
Plant-Produced Basic Fibroblast Growth Factor (bFGF) Promotes Cell Proliferation and Collagen Production
Authors: Rattanapisit Kaewta , Jantimaporn Angkana , Kaewpungsup Pornjira , Shanmugaraj Balamurugan , Pavasant Prasit , Namdee Katawut , Phoolcharoen Waranyoo 
Published: December 2020

AbstractHuman fibroblast growth factor regulates a broad spectrum of biological functions, including cell proliferation and tissue differentiation, and has a wider application in tissue engineering. Here, we described the production of human basic fibroblast growth factor in plants by using a geminiviral vector system. In this study, we transiently expressed basic fibroblast growth factor containing a C-terminus 8X-Histidine with and without a barley alpha amylase signal peptide in Nicotiana benthamiana. The expression level of basic fibroblast growth factor without the signal peptide was found to be higher than the basic fibroblast growth factor with the signal peptide. Further, the recombinant basic fibroblast growth factor was purified from the plant crude extract by two-step purification viz., ammonium sulfate precipitation and Ni-affinity chromatography. Our results demonstrated that the purified plant-produced basic fibroblast growth factor was biologically active and promotes the proliferation of human periodontal ligament stem cells and human follicle dermal papilla cells in vitro. Moreover, the plant-produced basic fibroblast growth factor also induced collagen production in human dermal fibroblast cells. Our results suggest the potential use of plant-produced basic fibroblast growth factor as an antiaging and hair growth-promoting agent in the cosmetic industry.
HSF1 Alleviates Microthrombosis and Multiple Organ Dysfunction in Mice with Sepsis by Upregulating the Transcription of Tissue-Type Plasminogen Activator
Authors: Li Tao , Chen Huan , Zhang Huali , Xiao Xianzhong , Shi Xueyan , Yin Leijing , Tan Chuyi , Gu Jia , Liu Yanjuan , Li Caiyan , Xiao Gui , Liu Ke , Liu Meidong , Tan Sipin , Xiao Zihui 
Published: December 2020

AbstractSepsis is a life-threatening complication of infection closely associated with coagulation abnormalities. Heat shock factor 1 (HSF1) is an important transcription factor involved in many biological processes, but its regulatory role in blood coagulation remained unclear. We generated a sepsis model in HSF1-knockout mice to evaluate the role of HSF1 in microthrombosis and multiple organ dysfunction. Compared with septic wild-type mice, septic HSF1-knockout mice exhibited a greater degree of lung, liver, and kidney tissue damage, increased fibrin/fibrinogen deposition in the lungs and kidneys, and increased coagulation activity. RNA-seq analysis revealed that tissue-type plasminogen activator (t-PA) was upregulated in the lung tissues of septic mice, and the level of t-PA was significantly lower in HSF1-knockout mice than in wild-type mice in sepsis. The effects of HSF1 on t-PA expression were further validated in HSF1-knockout mice with sepsis and in vitro in mouse brain microvascular endothelial cells using HSF1 RNA interference or overexpression under lipopolysaccharide stimulation. Bioinformatics analysis, combined with electromobility shift and luciferase reporter assays, indicated that HSF1 directly upregulated t-PA at the transcriptional level. Our results reveal, for the first time, that HSF1 suppresses coagulation activity and microthrombosis by directly upregulating t-PA, thereby exerting protective effects against multiple organ dysfunction in sepsis.
Transition-Metal-Catalyzed Cross-Coupling Reactions of Grignard Reagents
Authors: Hell Zoltán , Juhász Kinga , Magyar Ágnes 
Published: December 2020

AbstractTransition-metal-catalyzed cross-coupling of organo­halides, ethers, sulfides, amines, and alcohols (and derivatives thereof) with Grignard reagents, known as the Kumada–Tamao–Corriu reaction, can be used to prepare important intermediates in the synthesis of numerous­ biologically active compounds. The most frequently used transition metals are nickel, palladium, and iron, but there are several examples for cross-coupling reactions catalyzed by copper, cobalt, manganese, chromium, etc. salts and complexes. The aim of this review is to summarize the most important transition-metal-catalyzed cross-coupling reactions realized in the period 2000 to 2020.1	Introduction2	Nickel Catalysis3	Palladium Catalysis4	Iron Catalysis5	Catalysis by Other Transition Metals5.1	Cobalt Catalysis5.2	Copper Catalysis5.3	Manganese Catalysis5.4	Chromium Catalysis6	Conclusion
Change in neutron skin thickness after cluster-decay
Authors: Seif W M , Abdulghany A R , Hussein Z N 
Published: December 2020

Abstract
We investigate the change of the neutron-skin thickness from parent to daughter nuclei involved in the cluster decay process. The neutron-skin thickness is obtained using self-consistent Hartree–Fock–Bogolyubov calculations based on Skyrme-SLy4 effective nucleon–nucleon interaction. The experimental data of the cluster decay modes observed to date indicate that the shell effect then the released energy play the predominate role of determining the spontaneous cluster decay modes. The effect of the change in the neutron-skin thickness from parent to daughter nuclei comes next to them. The cluster decay preferably proceeds to yield the least possible increase in the neutron-skin thickness of the daughter nucleus (δ
n). δ
n decreases when the isospin-asymmetry of the emitted cluster increases. The relative stability of the radioactive nucleus and its corresponding partial half-life increase for the cluster decays leading to a significant increase in the neutron-skin thickness.
Magnus-force induced skyrmion–antiskyrmion coupling in inhomogeneous racetrack
Authors: Silva R C , Silva R L , Pereira A R 
Published: December 2020

Abstract
In this paper we investigate a magnetic racetrack consisting of a junction of three materials with different properties. Indeed, this magnetic system is composed by two distinct regions (racetracks) connected by a thin interface: the first region (termed sector 1) has isotropic in-plane magnetic chirality and supports skyrmion (S) excitations while the second (sector 3) has anisotropic chirality and consequently supports antiskyrmions (A). The interface, which would be a third region (sector 2, connecting sectors 1 and 3) located in the central part of the racetrack, is an easy-axis Heisenberg ferromagnetic material. The topological structures S and A are put in motion by applying a spin-polarized current. Under certain conditions, we show that the skyrmion and the antiskyrmion created in their respective sectors are simultaneously impelled to the interface (due to the Magnus force) to apparently become a unique object (a skyrmion–antiskyrmion pair or SAP). After glued by sector 2, the skyrmion and the antiskyrmion move together (as a SAP) along the direction of the applied current. It is also shown that such an engineered racetrack can support a sequence of several SAP structures in motion, forming a current.
Improved photovoltage of printable perovskite solar cells via Nb5+ doped SnO2 compact layer
Authors: Wang Shiyu , Shen Wenjian , Liu Jiale , Ouyang Tao , Wu Yue , Li Wenhui , Chen Mingyue , Qi Pengcheng , Lu Yu , Tang Yiwen 
Published: December 2020

Abstract
The state-of-the-art perovskite solar cells (PSCs) with SnO2 electron transporting material (ETL) layer displays the probability of conquering the low electron mobility and serious leakage current loss of the TiO2 ETL layer in photoelectronic devices. The rapid development of SnO2 ETL layer has brought perovskite efficiencies >20%. However, high density of defect states and voltage loss of high temperature SnO2 are still latent impediment for the long-term stability and hysteresis effect of photovoltaics. Herein, Nb5+ doped SnO2 with deeper energy level is utilized as a compact ETL for printable mesoscopic PSCs. It promotes carrier concentration increase caused by n-type doping, assists Fermi energy level and conduction band minimum to move the deeper energy level, and significantly reduces interface carrier recombination, thus increasing the photovoltage of the device. As a result, the use of Nb5+ doped SnO2 brings high photovoltage of 0.92 V, which is 40 mV higher than that of 0.88 V for device based on SnO2 compact layer. The resulting PSCs displays outstanding efficiency of 13.53%, which contains an ∼10% improvements compared to those without Nb5+ doping. Our study emphasizes the significance of element doping for compact layer and lays the groundwork for high efficiency PSCs.
MOF-derived ZnCo2O4@NiCo2S4@PPy core–shell nanosheets on Ni foam for high-performance supercapacitors
Authors: Zhu Jiahui , Wang Yan , Zhang Xubin , Cai Wangfeng 
Published: December 2020

Abstract
The ZnCo2O4@NiCo2S4@PPy core–shell nanosheets material is prepared by directly growing leaf-like ZnCo2O4 nanosheets derived from the metal-organic framework (MOF) on Ni foam (NiF) via chemical bath deposition and annealing methods and then combining with NiCo2S4 and PPy via electrodeposition methods. The special core–shell structure formed by MOF-derived ZnCo2O4, NiCo2S4 and PPy creates a bi-interface, which could significantly promote the contact between electrode and electrolyte, provide more active sites and accelerate electron/ion transfer. And the combination of these three materials also produces a strong synergistic effect, which could further improve the capacitive performance of the electrode. Therefore, the ZnCo2O4@NiCo2S4@PPy/NiF electrode exhibits the maximum areal capacitance (3.75 F cm−2) and specific capacitance (2507.0 F g−1) at 1 mA cm−2 and 0.5 A g−1, respectively. Moreover, its capacitance retention rate is still 83.2% after 5000 cycles. In addition, a coin-type hybrid supercapacitor is assembled and displays a high energy density of 44.15 Wh kg−1 and good cycling performance.
Towards the standardization of the absorbed dose report mode in high energy photon beams
Authors: Younes Tony , Chauvin Maxime , Delbaere Alexia , Labour Joey , Fonteny Victoria , Simon Luc , Fares Georges , Vieillevigne Laure 
Published: December 2020

Abstract
The benefits of using an algorithm that reports absorbed dose-to-medium have been jeopardized by the clinical experience and the experimental protocols that have mainly relied on absorbed dose-to-water. The aim of the present work was to investigate the physical aspects that govern the dosimetry in heterogeneous media using Monte Carlo method and to introduce a formalism for the experimental validation of absorbed dose-to-medium reporting algorithms. Particle fluence spectra computed within the sensitive volume of two simulated detectors (T31016 Pinpoint 3D ionization chamber and EBT3 radiochromic film) placed in different media (water, RW3, lung and bone) were compared to those in the undisturbed media for 6 MV photon beams. A heterogeneity correction factor that takes into account the difference between the detector perturbation in medium and under reference conditions as well as the stopping-power ratios was then derived for all media using cema calculations. Furthermore, the different conversion approaches and Eclipse treatment planning system algorithms were compared against the Monte Carlo absorbed dose reports. The detectors electron fluence perturbation in RW3 and lung media were close to that in water (≤1.5%). However, the perturbation was greater in bone (∼4%) and impacted the spectral shape. It was emphasized that detectors readings should be corrected by the heterogeneity correction factor that ranged from 0.932 in bone to 0.985 in lung. Significant discrepancies were observed between all the absorbed dose reports and conversions, especially in bone (exceeding 10%) and to a lesser extent in RW3. Given the ongoing advances in dose calculation algorithms, it is essential to standardize the absorbed dose report mode with absorbed dose-to-medium as a favoured choice. It was concluded that a retrospective conversion should be avoided and switching from absorbed dose-to-water to absorbed dose-to-medium reporting algorithm should be carried out by a direct comparison of both algorithms.
Proton FLASH: passive scattering or pencil beam scanning?
Authors: Zhang Guoliang , Wang Junliang , Wang Yuenan , Peng Hao 
Published: December 2020

Abstract
This study focused on a direct comparison of dose delivery efficiency between two proton FLASH delivery modes: passive scattering and pencil beam scanning (PBS). Monte-Carlo simulation of the beamline was performed using the Geant4 package. Two proton energies (63 and 230 MeV) were selected, targeting for shallow and deep-seated tumors, respectively. Two irradiation field sizes were selected: 13 × 13 mm2 and 50 × 50 mm2. For each delivery mode, two cases were investigated: shoot-through and Bragg peak, yielding a total of 4 delivery scenarios. For the passive scattering mode, the impact on dose rate by multiple components along the beamline were investigated, including ridge-filter, scatterer, range shifter and collimator. A quantitative comparison among four scenarios was made in terms of field size, dose, dose rate and treatment plan quality (dose volume histogram). For the 230 MeV case, the dose rate (for 1 nA current) is 0.05 Gy s−1 (passive with Bragg peak, field size: 50 × 50 mm2) and 2.6 Gy s−1 (PBS with shoot-through). Dose rate comparison is made between passive scattering and PBS as the delivery changes from spot-layer to shoot-through. In conclusion, the study successfully established a benchmark reference for dose rate performance for different scenarios, taking into account components along the beamline, field size and beam current. The results allow us to predict and compare the required beam current to yield a dose rate sufficiently high, above the threshold of the FLASH effect.
Concurrent validity of the portable gFlight system compared to a force plate to measure jump performance variables
Authors: Parmar Arran , Keenan Ashleigh , Barry Gill 
Published: December 2020

Abstract

Objective. Lower-limb strength and power is commonly assessed indirectly by measuring jump performance. A novel portable system (gFlight) that can be used in applied settings provides measures of jump performance. The aim of this study was to validate jump performance measures provided by the gFlight to those provided by a force plate. Approach. Thirty-six participants performed three countermovement jump (CMJ) and drop jump (DJ) trials. Jump height (JH), contact time, and reactive strength index (RSI) were simultaneously recorded by a force plate and gFlight sensors to assess concurrent validity. Main results. The gFlight provided significantly higher measures of JH during the CMJ (mean: +8.79 ± 4.16 cm, 95% CI: +7.68 to 9.90 cm, P < 0.001) and DJ (mean: +4.68 ± 3.57 cm, 95% CI: +3.73 to 5.63 cm, P < 0.001) compared to the force plate. The gFlight sensors displayed significantly higher measures of RSI (mean: +0.48 ± 0.39 m·s−1, 95% CI: +0.37 to 0.58 m·s−1, P < 0.001) and lower measures of contact time (mean: −0.036 ± 0.028 s, 95% CI: −0.044 to −0.029 s, P < 0.001) during the DJ compared to the force plate. The bias displayed by the gFlight for JH, contact time and RSI measures are reduced using corrective equations. Significance. The gFlight sensors are a cost-effective, portable measurement system with high concurrent and ecological validity for the objective measurement of jump performance in applied settings. Corrective equations should be used to reduce measurement biases so comparisons can be made to force plate measurements of jump performance.
A novel algorithm for automatic diagnosis of sleep apnea from airflow and oximetry signals
Authors: Uddin M B , Chow C M , Ling S H , Su S W 
Published: December 2020

Abstract

Objective. Sleep apnea significantly decreases the quality of life. The apnea hypopnea index (AHI) is the main indicator for sleep apnea diagnosis. This study explored a novel automatic algorithm to diagnose sleep apnea from nasal airflow (AF) and pulse oximetry (SpO2) signals. Approach. Of the 988 polysomnography (PSG) records from the sleep heart health study (SHHS), 45 were randomly selected for the development of an algorithm and the remainder for validation (n = 943). The algorithm detects apnea events by a digitization process, following the determination of the peak excursion (peak-to-trough amplitude) from AF envelope. Hypopnea events were determined from the AF envelope and oxygen desaturation with correction to time lag in SpO2. Total sleep time (TST) was estimated from an optimized percentage of artefact-free total recording time. AHI was estimated from the number of detected events divided by the estimated TST. The estimated AHI was compared to the scored SHHS data for performance evaluation. Main results. The validation showed good agreement between the estimated and scored AHI (intraclass correlation coefficient of 0.95 and mean ±95% limits of agreement of −1.6 ±12.5 events h−1). The diagnostic accuracies were found: 90.7%, 91%, and 96.7% for AHI cut-off ≥5, ≥15, and ≥30 respectively. Significance. The new algorithm is accurate over other existing methods for the automatic diagnosis of sleep apnea. It is applicable to any portable sleep screeners especially for the home diagnosis of sleep apnea.