bluuebunny/crossref_metadata_2025 huggingface dataset:
Inner Belt Electron Decay Timescales: A Comparison of Van Allen Probes and DREAM3D Losses Following the June 2015 Storm
Authors: Broll Jeffrey M. , Cunningham Gregory S. , Malaspina David M. , Claudepierre Seth G. , Ripoll Jean‐François
Published: May 2023

NASA's Van Allen Probes observed significant, long‐lived fluxes of inner belt electrons up to ∼1 MeV after geomagnetic storms in March and June 2015. Reanalysis of Magnetic Electron Ion Spectrometer (MagEIS) data with improved background correction showed a clearer picture of the relativistic electron population that persisted through 2016 and into 2017 above the Fennell et al. (2015, https://doi.org/10.1002/2014gl062874) limit. The intensity and duration of these enhancements allow estimation of decay timescales for comparison with simulated decay rates and theoretical lifetimes. We compare decay timescales from these data and DREAM3D simulations based on them using geomagnetic activity‐dependent pitch angle diffusion coefficients derived from plasmapause‐indexed wave data (Malaspina et al., 2016, https://doi.org/10.1002/2016gl069982, 2018, https://doi.org/10.1029/2018gl078564) and phase space densities derived from MagEIS observations. Simulated decay rates match observed decay rates more closely than the theoretical lifetime due to significantly nonequilibrium pitch angle distributions in simulation and data. We conclude that nonequilibrium effects, rather than a missing diffusion or loss process, account for observed short decay rates.
A Comparative Study on the Hot Dense Plasma and Cold Patch by Using Multi‐Instrument Observations
Authors: Ma Yu‐Zhang , Zhang Qing‐He , Lyons Larry , Oksavik Kjellmar , Xing Zan‐Yang , Hairston Marc , Nanan Balan , Hu Ze‐Jun , Wang Yong , Zhao Si‐Han
Published: May 2023

The polar cap hot patch is an enhanced density structure which is associated with particle precipitation, ion upflow and flow shears. Based on combined observations from DMSP satellites, EISCAT radar, and all‐sky imager at the Chinese Yellow River Station, the plasma characteristics and evolution of hot dense plasma and classical polar cap patch are investigated. Both of them show enhanced F region density, but the hot dense plasma is associated with higher electron temperature and enhanced E region electron density caused by particle precipitation. Compared to the cold patch, the hot dense plasma is closer to the cusp region and is associated with strong auroral emissions. Based on the joint observations, the evolution of the hot/cold dense plasma is discussed. In the initial phase the dense plasma comes from the sunlit lower latitude region, or from particle precipitation in the duskside auroral oval, and is heated locally by poleward moving auroral structures in the dayside auroral oval. Next the patches move poleward into the polar cap where a decaying electron temperature (i.e., less precipitation) gradually transform them into a cold patch.
Metamorphic Domes in Northern Tunisia: Exhuming the Roots of Nappe Belts by Widespread Post‐Subduction Delamination in the Western Mediterranean
Authors: Booth Rea G. , Gaidi S. , Melki F. , Marzougui W. , Ruano P. , Nieto F. , Azañón J. M. , Galvé J. P. , Hidas K. , Garrido C. J.
Published: May 2023

Cenozoic extension in the Western Mediterranean has been related to the dynamics of back‐arc domains. Although, in most of its orogenic belts extension propagated into the fore‐arc nappe domains. Here we revisit the structure, metamorphism and radiometric ages of the Tunisian Tell, where HP/LT rocks (350°C at 0.8 GPa), were exhumed by the sequential activity of extensional detachments after heating and decompression (410°C–440°C at 0.6–0.3 GPa) in a plate convergent setting. Normal faults thinning the Tunisian Tell detached at two different crustal levels. The shallower one cuts down into the Atlas Mesozoic sequence, involving Tellian Triassic evaporites in the hanging‐wall forming halokinetic structures in the Mejerda basin late Miocene. The deeper‐detachment bounds metamorphic domes formed by marbles and metapsammites from the Atlas domain. Illite crystallinity on Triassic rocks shows epizonal to anchizonal values, at deep and intermediate structural depths of the Tell‐Atlas nappe belt, respectively. New U‐Pb 49.78 ± 1.28 Ma rutile ages from Tellian metabasites, together with existing phlogopite 23–17 Ma K‐Ar ages in Atlas marbles from the footwall of the deepest detachment, indicate a polymetamorphic evolution. The Tell rocks underthrusted the Kabylian flysch in the early Eocene. Further, early Miocene shortening thrusted the metabasites over lower‐grade sediments, producing HP/LT metamorphism and ductile stretching at the base of the Atlas belt. The exhumation of midcrustal roots of Western Mediterranean nappe belts after tectonic shortening is a common feature related to tearing at the edges of the subduction systems and inboard delamination of their subcontinental lithospheric mantle.
Transient Bedload Transport During Flashflood Bores in a Desert Gravel‐Bed Channel
Authors: Halfi Eran , Thappeta Suresh K. , Johnson Joel P. L. , Reid Ian , Laronne Jonathan B.
Published: May 2023

Evidence of the effect of unsteady flow on bedload sediment transport is meager, particularly in desert rivers, despite its scientific, environmental and engineering importance. Our study of the phenomenon was conducted in Nahal Eshtemoa, Israel, an ephemeral river located in a semi‐arid area and subjected to flash floods. During 4 years, we monitored bedload transport and contemporaneous hydraulics, focusing on two intervals during which flow changed most rapidly: (a) the arrival of flood bores over dry river beds and (b) the propagation of subsequent bores over flowing water. Monitoring involved deployment of plate microphones, video cameras, surface velocity radar and a 3D velocimeter, enabling synchronized and unique data acquisition at high temporal resolution. We hypothesized that turbulence would be considerably elevated during the arrival of a flood bore and that this would induce transient entrainment of bedload. Our results demonstrate that bedload is indeed transported by the bore front and ceases soon after the arrival of most bores, even though water depth continues to rise. Bores arriving on a dry river bed usually generate higher bedload fluxes than bores advancing over flowing water. Elevated values of shear stress, turbulent kinetic energy and water‐surface slope occur as a bore impinges but then decrease. This is likely to be the explanation for high transient rates of bedload transport. Once the threshold depth previously determined as inducing continuous bedload motion is attained (≈40 cm), transport rates rise considerably relative to those associated with the bores.
Multiscale Nature of Atmospheric Rivers
Authors: Park Chanil , Son Seok‐Woo , Guan Bin
Published: May 2023

This study provides evidence for the multiscale nature of atmospheric rivers (ARs) by differentiating them based on high‐ (HF) and low‐frequency (LF) moisture transports. The HF‐dominant ARs exhibit migratory behavior as they are typically accompanied by extratropical cyclones. Their spatial distribution is seasonally synchronized with midlatitude storm activity. On the other hand, the LF‐dominant ARs stay in place as they are associated with quasi‐stationary circulation. They prevail in the subtropical monsoon regions in the summer hemisphere. The ARs are often jointly affected by HF and LF processes. Such intermediate ARs are frequently observed along the poleward boundary of subtropical highs. The latter two AR types are locally more persistent than the HF‐dominant ARs, implying the importance of LF dynamics in long‐lasting AR impacts. We suggest that multiscale analysis of ARs will offer valuable insights into their diversity and hydrological impacts.
The Effects of the Polar Rain on the Polar Wind Ion Outflow From the Nightside Ionosphere
Authors: Li Kun , Yang Qian , Cui Jun , Rong Zhaojin , Chai Lihui , Wei Yong , Yu Jiang , Liu Nigang , He Zhaoguo , Wang Jing
Published: May 2023

The polar wind, consisting of low‐energy ions and electrons, is an outflow along the open magnetic field lines from the polar cap ionosphere to the magnetosphere. Previous studies found that both solar radiation and solar wind electromagnetic energy are the two main energy sources for the polar wind. The polar rain, being field‐aligned precipitating electrons from the solar wind to the polar cap, may provide additional energies for the polar wind. This scenario is complicated as simulation studies show that polar rain changes the electric potential structures over the polar cap ionosphere. It is unclear how the polar rain affects the polar wind ion outflow. In this study, we show a positive correlation between the polar wind and the polar rain. Meanwhile, the polar wind is generally diminished in regions with strong Earth's magnetic field, suggesting the |B| modulates the penetration depth of the polar rain through the magnetic mirror force and thus the energy dissipation of the polar rain. Therefore, the polar rain can be an additional energy source for the polar wind although the polar rain has generally smaller energies and intensities than the particle precipitations in the auroral regions.
The Equatorward Boundary of the Auroral Current System During Magnetic Storms
Authors: Weygand James M. , Ngwira Chigomezyo M. , Arritt Robert F.
Published: May 2023

Our current knowledge of the geomagnetic poleward and equatorward boundary dynamics is limited, particularly, how deep those two latitudinal boundaries can extend into lower geomagnetic latitudes during magnetic storms. We want to understand the motion of the boundary because it is important in terms of the location and magnitude of the effects of geomagnetic disturbances associated with storms on the ground. In this study we derive spherical elementary ionospheric currents from ground magnetometer arrays covering North America and Greenland during six magnetic storms in 2015 and 2018. With two dimensional maps of the auroral region current, we select the equatorward boundary of the region 2 currents by‐eye and fit the boundary with an ellipse to derive the location of the equatorward boundary at magnetic midnight. We have obtained over 500 boundaries and find that the midnight boundary location varies between 45° and 66° magnetic latitude. We examine the influence of the interplanetary magnetic field (IMF), solar wind plasma, and geomagnetic indices on the location of the magnetic midnight equatorial boundary and find that the equatorial boundary location is best correlated with the IMF Bz, VBz, and the Sym‐H index. We demonstrate that as the Bz component becomes more negative, the magnitude of VBz increases, and the magnitude of the Sym‐H index increases, the magnetic midnight equatorial boundary shifts equatorward during periods of moderate to high geomagnetic activity.
Approximation of nearly-periodic symplectic maps via structure-preserving neural networks
Authors: Duruisseaux Valentin , Burby Joshua W. , Tang Qi
Published: May 2023

A continuous-time dynamical system with parameter$$\varepsilon$$εis nearly-periodic if all its trajectories are periodic with nowhere-vanishing angular frequency as$$\varepsilon$$εapproaches 0. Nearly-periodic maps are discrete-time analogues of nearly-periodic systems, defined as parameter-dependent diffeomorphisms that limit to rotations along a circle action, and they admit formalU(1) symmetries to all orders when the limiting rotation is non-resonant. For Hamiltonian nearly-periodic maps on exact presymplectic manifolds, the formalU(1) symmetry gives rise to a discrete-time adiabatic invariant. In this paper, we construct a novel structure-preserving neural network to approximate nearly-periodic symplectic maps. This neural network architecture, which we call symplectic gyroceptron, ensures that the resulting surrogate map is nearly-periodic and symplectic, and that it gives rise to a discrete-time adiabatic invariant and a long-time stability. This new structure-preserving neural network provides a promising architecture for surrogate modeling of non-dissipative dynamical systems that automatically steps over short timescales without introducing spurious instabilities.
High heat flux reduction to materials using current filaments
Authors: Le Trang , Suzuki Yasuhiro , Hasegawa Hiroki , Moritaka Toseo , Ohtani Hiroaki
Published: May 2023

Reducing high electron and ion heat fluxes is one of the critical issues for shielding satellites and spacecraft. One of the ideas for shielding high particle and heat fluxes is to apply an external magnetic field generated by injecting current filaments. In this work, we model a flow of plasma, which includes electrons and ions in a small region, by using two spatial dimensions and three coordinates for velocities (2D3V) Particle-In-Cell (PIC) code to study the effects of the injected current filaments on particle and heat fluxes to the wall. The plasma enters the simulation domain from the source region at the left boundary and is fully absorbed in the conductor wall at the right boundary. Current filaments are injected to change the magnetic field structure of the system. We compare particle density, particle flux, and heat flux with and without injecting the current filaments into the domain in two dimensions. Based on the simulation results, we found that injecting current filaments can reduce the peak fluxes to the wall and transfer some of those fluxes along the wall. Therefore, injecting the current filaments is a good candidate for shielding satellites and spacecraft from high-energy ion and electron fluxes.
Therapeutic effects of axitinib, an anti-angiogenic tyrosine kinase inhibitor, on interstitial cystitis
Authors: Shin Jung Hyun , Ryu Chae-Min , Yu Hwan Yeul , Park Yang Soon , Shin Dong-Myung , Choo Myung-Soo
Published: May 2023

To investigate the therapeutic effects of axitinib, a tyrosine kinase inhibitor, in an interstitial cystitis (IC) rat model. IC patients with or without Hunner lesion and non-IC controls were enrolled (n = 5/group). Bladder tissues were stained with vascular endothelial growth factor (VEGF), VEGF receptor 2 (VEGFR-2), platelet-derived growth factor (PDGF), and PDGF receptor B (PDGFR-B). The IC group showed extensive VEGFR-2 and PDGFR-B staining compared with controls. Next, ten-week-old female Sprague Dawley rats were divided into three groups (n = 10/group): sham, hydrochloride (HCl), and axitinib groups. One week after HCl instillation (day 0), the axitinib group received oral axitinib (1 mg/kg) for five consecutive days and pain was evaluated daily. Bladder function, histology and genetics were evaluated on day 7. The pain threshold significantly improved 3 days after axitinib administration. Axitinib decreased non-voiding contraction and increased the micturition interval and micturition volume and alleviated urothelial denudation, angiogenesis, mast cell infiltration, and fibrosis. HCl instillation increased the expression of tyrosine kinase receptors, including VEGFR-2 and PDGFR-B; axitinib administration inhibited their expression. Oral administration of axitinib improved pain, voiding profiles, and urothelial integrity by inhibiting angiogenesis in IC rat model. Axitinib may have potential therapeutic efficacy in IC patients.
Live birth rate following a failed first in vitro fertilization cycle with no embryos for transfer
Authors: Dong Xiaohui , Xue Xia
Published: May 2023

After a failed in vitro fertilization (IVF) procedure in which no transferable embryo was obtained, the possibility of a subsequent pregnancy for the patient is unknown. We conducted a cohort retrospective study evaluating the live birth rate in the subsequent cycles of the patients with no embryo for transfer in their first IVF attempt between 2017and 2020. The first cycle variables of patients who conceived in subsequent cycles were compared to those who did not. Additionally, for patients who conceived at last, variables related to ovarian stimulation were compared between the first cycle and the conceiving cycle. In accordance with the inclusion criteria, 529 were enrolled during the study period, of which 230 had successful pregnancies and 192 gave birth to a live infant. Cumulative live birth rates (CLBR) per cycle and patient were 26% and 36% respectively. Moreover, 99% of the live births were obtained within the first three attempts, beyond six cycles, there was no pregnancy. Stimulating variables in the first cycle were not effective in predicting the likelihood of a patient's subsequent pregnancy. Overall, patients who did not have embryos available for transfer in the first cycle had a 36% chance of getting a live birth in subsequent attempts, and the cause of failure should be considered.
Full-duplex multi-user MIMO communication systems performance optimization using leakage-based precoding
Authors: Teklu Merhawit Berhane , Choi Dong-You , Meng Wei-Xiao
Published: May 2023

The spectral efficiency (SE) can approximately double when using full-duplex (FD) multiuser MIMO communications. However, there are difficulties because of multiuser interferences, self-interference (SI), and co-channel interference (CCI). To improve the SE of the downlink (DL), this paper proposes CCI-aware enhancement to SLNR (signal-to-leakage-and-noise-ratio) signal-to-leakage-and-noise-ratio (SLNR). It considers a suppressing filter at the receiver to cancel the interferences again designing a beamformer based on CCI-plus-noise covariance matrices for every user at the transmitting side. Additionally, we propose an improvement in the SLNR method by using SI-plus-noise covariance matrices to design uplink (UL) beamformers. Unlike zero-forcing and block-diagonalization, the SLNR approach serves numerous antennas at users and BS (base station). The total SE of the communication yielded using the optimized precoder, i.e., obtained from the SLNR-based precoding. To achieve maximum energy efficiency (EE), we use a power consumption model. Simulation results confirm that full-duplex performs well compared to half-duplex (HD) when the number of antennas at every user in uplink as well downlink channels grow, for all Rician factors, for slight powers of the CCI and SI, and a limited number of antennas at the BS. With the proposed scheme for given transmit power and circuit power, we demonstrate that FD has a higher EE than HD.
Renin-angiotensin system inhibitors mitigate radiation pneumonitis by activating ACE2-angiotensin-(1–7) axis via NF-κB/MAPK pathway
Authors: Cong Changsheng , Niu Shiying , Jiang Yifan , Zhang Xinhui , Jing Wang , Zheng Yawen , Zhang Xiaoyue , Su Guohai , Zhang Yueying , Sun Meili
Published: May 2023

Radiation pneumonitis (RP) affects both patients and physicians during radiation therapy for lung cancer. To date, there are no effective drugs for improving the clinical outcomes of RP. The activation of angiotensin-converting enzyme 2 (ACE2) improves experimental acute lung injury caused by severe acute respiratory syndrome coronavirus, acid inhalation, and sepsis. However, the effects and underlying mechanisms of ACE2 in RP remain unclear. Therefore, this study aimed to investigate the effects of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers on RP and ACE2/angiotensin-(1–7)/Mas receptor pathway activation. We found that radiotherapy decreased the expression of ACE2 and that overexpression of ACE2 alleviated lung injury in an RP mouse model. Moreover, captopril and valsartan restored ACE2 activation; attenuated P38, ERK, and p65 phosphorylation; and effectively mitigated RP in the mouse model. Further systematic retrospective analysis illustrated that the incidence of RP in patients using renin-angiotensin system inhibitors (RASis) was lower than that in patients not using RASis (18.2% vs. 35.8% at 3 months, p = 0.0497). In conclusion, the current findings demonstrate that ACE2 plays a critical role in RP and suggest that RASis may be useful potential therapeutic drugs for RP.
Higher-order topological corner state in a reconfigurable breathing kagome lattice consisting of magnetically coupled LC resonators
Authors: Yatsugi Kenichi , Pandarakone Shrinathan Esakimuthu , Iizuka Hideo
Published: May 2023

Higher-order topological insulators are attracting attention from fundamental interest to fascinating applications, owing to the topological properties with higher-order topological corner states. Breathing kagome lattice is a prospective platform which can support higher-order topological corner states. Here, we experimentally demonstrate that higher-order topological corner states are supported in a breathing kagome lattice consisting of magnetically coupled resonant coils. The winding direction of each coil is determined to hold C3 symmetry for each triangle unit cell, enabling to emerge higher-order topological corner states. In addition, topological and trivial phases can be switched by changing the distances between the coils. The emergence of corner states in the topological phase is experimentally observed through admittance measurements. As an illustration, wireless power transfer is performed between the corner states, and between the bulk and corner states. The proposed configuration is a promising platform for not only investigating topological properties of the breathing kagome lattice but also an alternative mechanism of selective wireless power transfer.
Evaluation of airway involvement and treatment in patients with relapsing polychondritis
Authors: Handa Hiroshi , Ooka Seido , Shimizu Jun , Suzuki Noboru , Mineshita Masamichi
Published: May 2023

Airway involvement in relapsing polychondritis (RP) can be debilitating and life threatening, often requiring interventional procedures. If standard therapies including systemic corticosteroid and immunosuppressive agents are ineffective, airway stenting is often required. Recently, biologics have been reported to be effective for RP, and the early administration of biologics may avoid airway stenting. To evaluate survival rates and treatment approaches, medical records of RP patients with airway involvement were reviewed. These cases were divided into the following groups: with and without malacia, stenting and non-stenting, and with and without biologics. Kaplan–Meier was used to calculate survival rates and log rank tests were used to analyze biologics groups. A total of 77 patients were enrolled. Airway stenting was performed in 13 patients, all of which developed airway malacia. The stenting group had significantly lower survival rates than the non-stenting group (p < 0.001). Stent-related complications were granulation tissue (85%) and mucostasis (69%). In the non-stenting group, a lower mortality rate was observed. A significantly higher survival rate was seen in patients administered biologics than without (p = 0.014). The early administration of biologics shows promise in preventing severe airway disorders that require airway stenting.
Adaptable platform for trapped cold electrons, hydrogen and lithium anions and cations
Authors: Azevedo L. O. A. , Costa R. J. S. , Wolff W. , Oliveira A. N. , Sacramento R. L. , Silveira D. M. , Cesar C. L.
Published: May 2023

Cold cations, electrons and anions are ubiquitous in space, participate in star formation chemistry and are relevant to studies on the origin of molecular biology homochirality. We report on a system to generate and trap these species in the laboratory. Laser ablation of a solid target (LiH) facing a sublimating Ne matrix generates cold electrons, anions, and cations. Axial energy distributions (of $${{{{{{\rm{e}}}}}}}^{-}$$

e

−

, $${{{{{{\rm{H}}}}}}}^{\pm }$$

H

±

and $${{{{{{\rm{Li}}}}}}}^{\pm }$$

Li

±

) peaked at 0–25 meV are obtained in a Penning trap at 90 mT and 0.5 eV barrier. Anions can be guided and neutralized with low recoil energy by near–threshold photodetachment. An immediate prospect for this $${{{{{{\rm{H}}}}}}}^{-}$$

H

−

source is to load hydrogen atoms into the ALPHA antihydrogen trap at CERN toward direct spectroscopic comparison of both conjugated species beyond 13 significant figures. The production is potentially scalable and adaptable to different species including deuterium and tritium, relevant for neutrino mass and fusion research.
Lattice engineering of AuPd@Pt core–shell icosahedra for highly efficient electrocatalytic ethanol oxidation
Authors: Qian Ningkang , Ding Degong , Ji Liang , Li Junjie , Zhang Hui , Yang Deren
Published: May 2023

Lattice engineering of AuPd@Pt core–shell icosahedra for the exploration of the mechanism of the ethanol oxidation reaction.
Sustainable polar aprotic/poly-deep eutectic solvent systems for highly efficient dissolution of lignin
Authors: Liu Qiaoling , Wang Yang , Bian Jing , Li Ming-Fei , Ren Jun-Li , Hao Xiang , Peng Feng
Published: May 2023

Novel sustainable polar aprotic/poly-deep eutectic solvent systems are designed for the highly efficient and applicable dissolution of different types of lignin.
Joint optimization of recommendation and caching based on user preference prediction
Authors: Chen Xiaoqi , Zhu Qi , Hua Yu
Published: May 2023

The development of the Internet of things brings exponential growth of wireless traffic, which puts great pressure on the backhaul link. The proactive caching of some contents in the edge device of mobile network can effectively reduce the repeated transmission of the same contents and relieve the burden of the backhaul link. Moreover, the introduction of recommendation mechanisms can reshape user's request and improve cache hit ratio. However, the optimization of recommendation and caching decisions is highly dependent on the users’ preference information for files. Here, a joint optimization algorithm of recommendation and caching based on users’ preference prediction with multiple base stations cooperative caching is proposed. To improve the caching efficiency, the Deep Crossing model is adopted to predict users’ preferences. Under the constraints of cache capacity, recommendation quantity and bandwidth, an optimization problem to minimize the total transmission delay of the system is formulated. Then, the NP‐hardness of the proposed optimization problem is proved and it is decoupled it into three sub‐problems, namely recommendation, user access and caching optimization sub‐problems. Simulation results show that the proposed algorithm can effectively reduce the total transmission delay of the system.
Prescribed performance fault‐tolerant attitude control for flexible spacecraft under limited communication network
Authors: Liu Ming , Liu Qiuhong , Yue Chengfei , Li Huayi
Published: May 2023

This paper investigates the prescribed performance fault‐tolerant attitude tracking control for flexible spacecraft under limited communication network, where the controller and the actuator are connected via wireless network. The hysteresis quantizer is employed to quantize the control signal, which can reduce the communication burden of the network onboard. First, a novel iterative learning observer is developed by combining with neural‐network approximation method to reconstruct the actuator faults and estimate the unmeasurable nonlinear rigid‐flexible dynamics simultaneously. Then, the signal quantization technique is introduced for control command quantization, and the concerned parametric quantization error is given. Based on the learning observer output, prescribed performance design procedure, and a quantization error compensation method, an active fault‐tolerant control strategy is developed for flexible spacecraft attitude tracking to deal with actuator faults, unmeasurable system nonlinearity, quantization errors, and external disturbances. The stability analysis of the closed‐loop system proves that the quantization errors, modal vibrations, disturbances can be effectively rejected, moreover, the convergence of the transformed performance states and angular velocity states can be guaranteed, which achieves the tracking problem with predetermined transient‐state and steady‐state performance requirements. Finally, a numerical simulation is conducted to illustrate the validness of the proposed control strategy.
Image feature learning combined with attention‐based spectral representation for spatio‐temporal photovoltaic power prediction
Authors: Guo Xingchen , Lai Jing , Zheng Zhou , Lin Chenxiang , Dai Yuxing , Xu Xuexin , San Haisheng , Jia Rong , Zhang Zhihong
Published: May 2023

Clean energy is a major trend. The importance of photovoltaic power generation is also growing. Photovoltaic power generation is mainly affected by the weather. It is full of uncertainties. Previous work has relied chiefly on historical photovoltaics data for time series forecasts. However, unforeseen weather conditions can sometimes skew. Consequently, a spatial‐temporal‐meteorological‐long short‐term memory prediction model (STM‐LSTM) is proposed to compensate for the shortage of photovoltaic prediction models for uncertainties. This model can simultaneously process satellite image data, historical meteorological data, and historical power generation data. In this way, historical patterns and meteorological change information are extracted to improve the accuracy of photovoltaic prediction. STM‐LSTM processes raw satellite data to obtain cloud image data. It can extract cloud motion information using the dense optical flow method. First, the cloud images are processed to extract cloud position information. By adaptive attentive learning of images in different bands, a better representation for subsequent tasks can be obtained. Second, it is important to process historical meteorological data to learn meteorological change patterns. Last but not least, the historical photovoltaic power generation sequences are combined to obtain the final photovoltaic prediction results. After a series of experimental validation, the performance of the proposed STM‐LSTM model has a good improvement compared with the baseline model.
Simulation study of integrated‐gate‐commutated‐thyristor based superconducting hybrid direct current circuit breaker
Authors: Junaid Muhammad , Yu Wenqing , Cao Shuzhi , Yu Xiaolong , Yu Dongsheng , Zong Weilin , Wang Jianhua
Published: May 2023

With the development of a distributed generation, direct current (DC) load and energy‐storage equipment, voltage‐source‐converter‐based medium‐voltage DC systems (VSC‐MVDC) have attracted more attention due to its low power consumption, high reliability, independent power control and so on. However, VSC‐MVDC has the problem of DC fault isolation, which requires the fast‐acting DC circuit‐breakers to isolate faulty lines and ensure low cost. This problem can be solved by coordinating resistive type superconducting‐fault‐current‐limiter (R‐SFCL) and integrated‐gate‐commutated‐thyristor (IGCT) based hybrid circuit breaker. Based on this, IGCT based superconducting DC circuit breaker (SDCCB) is proposed and analysed. Combining R‐SFCL with IGCT could realise large current limiting and interruption and ensure low cost. In addition, the IGCT based hybrid DC circuit breaker (IGCT‐HDCCB) is compared with the traditional insulated gate bipolar transistor (IGBT) based hybrid DC circuit breaker (IGBT‐HDCCB) to evaluate which circuit breaker is more suitable for VSC‐MVDC. The results show that, coordination based on R‐SFCL and SDCCB, the fault current is successfully limited from 17.6 to 2.1 kA, and then interrupted within 3.8 ms. In addition, IGCT‐HDCCB overcomes the disadvantage that IGCT has less interrupting capacity than IGBT, retains the advantage of low cost of IGCT and is more suitable for MVDC system.
Global spatio‐temporal dynamic capturing network‐based traffic flow prediction
Authors: Sun Haoran , Wei Yanling , Huang Xueliang , Gao Shan , Song Yuhang
Published: May 2023

Capturing the complex spatio‐temporal relationships of traffic roads is essential to accurately predict traffic flow data. Traditional models typically collect spatial and temporal relationships and increase the complexity of the model by considering connected and unconnected roads. However, global road networks are dynamic and hidden connectivity relationships generally undergo variations over time. A deterministic single‐connection correlation inevitably limits the learning capability of the model. In this paper, the authors propose a global spatio‐temporal dynamic capturing network (GSTDCN) for traffic flow prediction. First, the global encoding module based on the attention mechanism is set up to describe the dynamic spatio‐temporal relationships. It is shown that GSTDCN can learn the hidden node information by spatial correlation at different times. Meanwhile, an effective temporal prediction module is constructed, which facilitates the data augmentation and improves the prediction results of GSTDCN. The model is experimented on four public transportation datasets, and the results show that the GSTDCN outperforms the state‐of‐the‐art baseline.
Nearly‐optimal control for energy, thermal, and storage loads with energy disaggregation monitoring: A case of residential management for the elderly
Authors: Tsaknakis Christos , Korkas Christos , Pippi Kalliopi , Athanasiadis Christos , Alexopoulou Vasiliki , Kosmatopoulos Elias , Nikolaidis Vassilis C. , Papadopoulos Theofilos
Published: May 2023

The increase in the ageing of the population calls for advanced monitoring and actuation systems for the smart control and management of elderly households that should manage to optimise multi‐objective control problems. This study proposes a state‐of‐art approach, based on Approximate Dynamic Programming, that tackles multiple challenges, aiming to maximise the energy efficiency, the electricity cost reduction, the user comfort, and the load monitoring of a typical Greek residency (simulated in EnergyPlus), including both controllable and uncontrollable loads, an energy storage system, and power generation units. The article presents the various simulated loads, pricing schemes under Greek regulations and variety of control strategies that are co‐ordinately used to minimise the defined objective functions in contrast to the current state‐of‐the‐art approaches. The latter either focus on single objective problems or use simpler iterative and often limited to specific variables, approaches for multi‐objective control. Finally, the presented results provide insights for the optimal and safe residential management and validate the performance of the proposed control strategy in comparison with alternative demand response strategies, offering improved performance by 20% in terms of energy efficiency, cost reduction, and thermal comfort.
High-resolution imaging of solar pores
Authors: Kamlah R. , Verma M. , Denker C. , Wang H.
Published: May 2023

Context.Light bridges are bright, long, and narrow features that are typically connected to the formation or decay processes of sunspots and pores.

Aims.The interaction of magnetic fields and plasma flows is investigated in the trailing part of an active region, where pores and magnetic knots evolve into a complex sunspot. The goal is to identify the photospheric and chromospheric processes, which transform the mainly vertical magnetic fields of pores into a sunspot with multiple umbral cores, light bridges, and rudimentary penumbrae.

Methods.Conducting observations with a broad variety of telescopes and instruments provides access to different atmospheric layers and the changing morphology of features connected to strong magnetic fields. While the Helioseismic and Magnetic Imager (HMI) of the Solar Dynamics Observatory (SDO) provides full-disk continuum images and line-of-sight magnetograms, the fine structure and flows around a pore can be deduced from high-resolution observations in various wavelengths as provided by theGoodeSolar Telescope (GST) at the Big Bear Solar Observatory (BBSO). Horizontal proper motions are evaluated applying local correlation tracking (LCT) to the available time series, whereas the connectivity of sunspot features can be established using the background-subtracted activity maps (BaSAMs).

Results.Photospheric flow maps indicate radial outflows, where the light bridge connects to the surrounding granulation, whereas inflows are present at the border of the pores. In contrast, the chromospheric flow maps show strong radial outflows at superpenumbral scales, even in the absence of a penumbra in the photosphere. The region in between the two polarities is characterized by expanding granules creating strong divergence centers. Variations in BaSAMs follow locations of significant and persistent changes in and around pores. The resulting maps indicate low variations along the light bridge, as well as thin hairlines connecting the light bridge to the pores and strong variations at the border of pores. Various BaSAMs demonstrate the interaction of pores with the surrounding supergranular cell. The Hαline-of-sight velocity maps provide further insights into the flow structure, with twisted motions along some of the radial filaments around the pore with the light bridge. Furthermore, flows along filaments connecting the two polarities of the active region are pronounced in the line-of-sight velocity maps.

Conclusions.The present observations reveal that even small-scale changes of plasma motions in and around pores are conducive to transform pores into sunspots. In addition, chromospheric counterparts of penumbral filaments appear much earlier than the penumbral filaments in the photosphere. Penumbra formation is aided by a stable magnetic feature that anchors the advection of magnetic flux and provides a connection to the surrounding supergranular cell, whereas continuously emerging flux and strong light bridges are counteragents that affect the appearance and complexity of sunspots and their penumbrae.
Du modèle établi au terrain en humanités en santé
Authors: Vanhoutte Lucie
Published: May 2023

Cet article explore les interactions entre « terrain » et outils théoriques à partir de l’étude d’un cas, celui d’une approche anthropologique de la transition nutritionnelle chez les adultes, en milieu rural, au Sénégal. Le terrain est ici défini à la fois comme un espace aux contours définis par le projet de recherche, d’où sont extraites les données étudiées, et comme une forme d’expérience de recherche, « faire du terrain ». Notre étude de cas mobilise un modèle théorique, celui de la transition nutritionnelle, qui a vocation à décrire, à l’échelle mondiale, l’imbrication de changements à la fois épidémiologiques et socio-économiques. À quelles conditions l’étude d’un terrain donné peut-elle s’appuyer sur ce type de modèle, qui est par essence généraliste et donc, dans une certaine mesure inadapté à la complexité de toute réalité située ?
Roman κ-domination revisited
Authors: Abd Aziz Noor A’lawiah , Jafari Rad Nader , Kamarulhaili Hailiza
Published: May 2023

Kammerling and Volkmann [J. Korean Math. Soc. 46 (2009) 1309–1318] introduced the concept of Roman κ-domination in graphs. For a fixed positive integer κ, a function f : V(G) → {0, 1, 2} is a Roman κ-dominating function on G if every vertex valued 0 under f is adjacent to at least κ vertices valued 2 under f. In this paper, inspired by the concept of alliances in graphs, we revisit the concept of Roman κ-domination by not-fixing κ. We prove upper bounds for the new variant in cactus graphs and characterize cactus graph achieving equality for the given bound. We also present a probabilistic upper bound for this variant.
Global Existence and Extinction Behaviour for a Doubly Nonlinear Parabolic Equation with Logarithmic Nonlinearity
Authors: LIU Dengming , CHEN Ao
Published: May 2023

This paper is mainly focused on the global existence and extinction behaviour of the solutions to a doubly nonlinear parabolic equation with logarithmic nonlinearity. By making use of energy estimates method and a series of ordinary differential inequalities, the global existence of the solution is obtained. Moreover, we give the sufficient conditions on the occurrence (or absence) of the extinction behaviour.
A Novel DBN-EFA-CFA-Based Dimensional Reduation for Credit Risk Measurement
Authors: ZHANG Yue , HUANG Zhenzhen , SHI Longmei , ZOU Jian
Published: May 2023

Affected by the Federal Reserve's interest rate hike and the downward pressure on the domestic economy, the phenomenon of default is still prominent. The credit risk of the listed companies has become a growing concern of the community. In this paper we present a novel credit risk measurement method based on a dimensional reduation technique. The method first extracts the risk measure indexes from the basal financial data via dimensional reduation by using deep belief network (DBN), exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) in turn. And then the credit risk is measured by a systemic structural equation model (SEM) and logistic distribution. To validate the proposed method, we employ the financial data of the listed companies from Q1 2019 to Q2 2022. The empirical results show its effectiveness on statistical evaluation, assessment on testing samples and credit risk forecasting.
Periocular Biometric Recognition for Masked Faces
Authors: HUANG Qiaoyue , TANG Chaoying , ZHANG Tianshu
Published: May 2023

Since the outbreak of Coronavirus Disease 2019 (COVID-19), people are recommended to wear facial masks to limit the spread of the virus. Under the circumstances, traditional face recognition technologies cannot achieve satisfactory results. In this paper, we propose a face recognition algorithm that combines the traditional features and deep features of masked faces. For traditional features, we extract Local Binary Pattern (LBP), Scale-Invariant Feature Transform (SIFT) and Histogram of Oriented Gradient (HOG) features from the periocular region, and use the Support Vector Machines (SVM) classifier to perform personal identification. We also propose an improved Convolutional Neural Network (CNN) model Angular Visual Geometry Group Network (A-VGG) to learn deep features. Then we use the decision-level fusion to combine the four features. Comprehensive experiments were carried out on databases of real masked faces and simulated masked faces, including frontal and side faces taken at different angles. Images with motion blur were also tested to evaluate the robustness of the algorithm. Besides, the experiment of matching a masked face with the corresponding full face is accomplished. The experimental results show that the proposed algorithm has state-of-the-art performance in masked face recognition, and the periocular region has rich biological features and high discrimination.
A Blockchain-Based Certificate System with Credit Self-Adjustment
Authors: ZHOU Wang , TAO Jun , LI Xin
Published: May 2023

Currently, digital certificate systems based on blockchain have been extensively developed and adopted. However, most of them do not take into account the certificate quality. To evaluate the credibility of certificates issued by educational institutions, we propose a novel blockchain-based system with credit self-adjustment (BC-CS). In BC-CS, employers can provide feedback according to the performances of their employees (i.e., students) holding different certificates. Based on the feedback, BC-CS automatically adjusts the certificate credits by using our proposed credit self-adjustment algorithm. To verify the feasibility of our proposed system, a decentralized application prototype has been developed on an Ethereum network. Experimental results demonstrate that the proposed system can fully support multi-step accreditation and automatic adjustment for certificate credit.
Role of miR-128/216a Regulating Isl1 Expression during Differentiation of Human Umbilical Cord Mesenchymal Stem Cells into Insulin-Producing Cells
Authors: MU Tianchi , WANG Tao , GAO Zhenyu , PAN Xin , LIU Yingxue
Published: May 2023

Islet-1 (Isl1), a LIM homeodomain protein, is expressed in the embryonic pancreatic epithelium. As a key transcription factor, Isl1 can not only regulate insulin gene expression in normal glucose condition but also maintain β-cell function and impact pancreatic β-cell target genes. Some experiments have suggested that MicroRNA (miRNA) can play a critical role during the induction of insulin-producing cells (IPCs). However, it is unclear whether miRNA may regulate Isl1 expression during differentiation of human umbilical cord mesenchymal stem cells (HUMSCs) into IPCs. In this investigation, we induced HUMSCs into IPCs with a modified two-step protocol, activin A, retinoic acid (step1) and conophylline, nicotinamide (step2). To find the miRNA regulating Isl1 expression, we respectively used TargetScan, miRDB and RNAhybrid to predict and got the result, miR-128 and miR-216a. The miRNAs can inhibit Isl1 expression by dual luciferase assay. The results of real-time Polymerase Chain Reaction (PCR) showed that Isl1 expression level was almost reciprocal to that of miR-128 and miR-216a during differentiation of HUMSCs into IPCs. Furthermore, over-expression of miR-128 or miR-216a down-regulated expression levels of Isl1 and MafA. Therefore, miR-128 or miR-216a may regulate expression of islet-specific transcription factors to control differentiation of HUMSCs into IPCs.
Mehr Leichtigkeit für schwere Beine
Authors: Welsch Katja
Published: May 2023

Varikosis ist weitverbreitet: Etwa die Hälfte der Bevölkerung ist davon betroffen. Allerdings ist die Venenschwäche nur in 10 % der Fälle medizinisch relevant ausgeprägt. Die Gefäßveränderung – umgangssprachlich auch Krampfadern genannt – hängt sowohl von der Veranlagung als auch von den Lebensumständen der Patienten ab. Die homöopathischen Arzneien, die hier vorgestellt werden, können die Beschwerden im akuten wie im chronischen Kontext verbessern und selbst bei Ulzeration als begleitende Therapie hilfreich sein.
Synthesis of Bioactive Macrocycles Involving Ring-Closing Metathesis Strategy
Authors: Ansary Inul , Jahan Nasrin
Published: May 2023

This review reports the synthesis of various bioactive macrocycles, involving ring-closing metathesis as a key step, developed since ca. 2000. These macrocycles exhibited biological activities such as antiviral, antifungal, antibacterial, and anticancer activities, and more. Thus, their syntheses and utilization are essential for both synthetic organic and medicinal chemists.
Exploring the Impact of Two Feedback Types on Speech Intelligibility, Precision, and Naturalness
Authors: Bislick Lauren , Thakar Ashka , Madden Elizabeth Brookshire
Published: May 2023

This pilot study examined the impact of feedback type on learning a novel speech task, as measured by listener ratings, and will inform procedures for future investigations within a larger sample size. Twenty-four native monolingual English-speaking college-aged adults participated in a single training session to learn novel Hindi phrases. Participants were randomly placed into one of three feedback groups: knowledge of performance (KP), knowledge of results (KR), or a combined KP + KR condition. Participant performance was assessed at 1 day and 1 week post-training. Participant responses were audio recorded and judged for intelligibility, precision, and naturalness by native Hindi speakers, blind to the feedback conditions, via rating scales. At 2 days post-training, participants in the KP and KP + KR feedback conditions were rated as performing better than participants in the KR condition on all three perceptual measures. At 1 week post-training, participants in the KP feedback condition were judged to be superior across all three perceptual measures. Preliminary findings suggest that augmented feedback enhances learning, especially when skills are considered novel and learners are unable to rely on their own internal feedback. These results may have implications for the application of motor learning principles into clinical practice for persons with motor speech disorders.