bluuebunny/crossref_metadata_2025_split huggingface dataset:
An investigation of kV mini-GRID spatially fractionated radiation therapy: dosimetry and preclinical trial
Authors: Johnson Timothy R , Bassil Alex M , Williams Nerissa T , Brundage Simon , Kent Collin L , Palmer Greg , Mowery Yvonne M , Oldham Mark 
Published: January 2022

Abstract

Objective. To develop and characterize novel methods of extreme spatially fractionated kV radiation therapy (including mini-GRID therapy) and to evaluate efficacy in the context of a pre-clinical mouse study. Approach. Spatially fractionated GRIDs were precision-milled from 3 mm thick lead sheets compatible with mounting on a 225 kVp small animal irradiator (X-Rad). Three pencil-beam GRIDs created arrays of 1 mm diameter beams, and three ‘bar’ GRIDs created 1 × 20 mm rectangular fields. GRIDs projected 20 × 20 mm2 fields at isocenter, and beamlets were spaced at 1, 1.25, and 1.5 mm, respectively. Peak-to-valley ratios and dose distributions were evaluated with Gafchromic film. Syngeneic transplant tumors were induced by intramuscular injection of a soft tissue sarcoma cell line into the gastrocnemius muscle of C57BL/6 mice. Tumor-bearing mice were randomized to four groups: unirradiated control, conventional irradiation of entire tumor, GRID therapy, and hemi-irradiation (half-beam block, 50% tumor volume treated). All irradiated mice received a single fraction of 15 Gy. Results. High peak-to-valley ratios were achieved (bar GRIDs: 11.9 ± 0.9, 13.6 ± 0.4, 13.8 ± 0.5; pencil-beam GRIDs: 18.7 ± 0.6, 26.3 ± 1.5, 31.0 ± 3.3). Pencil-beam GRIDs could theoretically spare more intra-tumor immune cells than bar GRIDs, but they treat less tumor tissue (3%–4% versus 19%–23% area receiving 90% prescription, respectively). Bar GRID and hemi-irradiation treatments significantly delayed tumor growth (P < 0.05), but not as much as a conventional treatment (P < 0.001). No significant difference was found in tumor growth delay between GRID and hemi-irradiation. Significance. High peak-to-valley ratios were achieved with kV grids: two-to-five times higher than values reported in literature for MV grids. GRID irradiation and hemi-irradiation delayed tumor growth, but neither was as effective as conventional whole tumor uniform dose treatment. Single fraction GRID therapy could not initiate an anti-cancer immune response strong enough to match conventional RT outcomes, but follow-up studies will evaluate the combination of mini-GRID with immune checkpoint blockade.
Study of anisotropy in the superconducting properties of FeTe0.55Se0.45 single crystal grown by the self-flux method
Authors: Chauhan Himanshu , Kumar Rohit , Varma G D 
Published: January 2022

Abstract
We report anisotropy in the superconducting properties of FeTe0.55Se0.45 bulk single crystal synthesized via the self-flux method. We have performed magnetotransport, magnetic and heat capacity measurements on single crystals of same batch. The grown crystals have also been characterized by XRD, XPS and Raman measurements. The superconductivity at T
C ∼ 14 K has been affirmed by the temperature-dependent resistivity, magnetic, and specific heat measurements. The anisotropy in the upper critical field (H
C2), coherence length (ξ), and critical current density (J
C) have been studied from the magnetotransport and magnetic measurements, respectively, under applied magnetic fields of 0–12 T along the ab-plane and c-axis. The critical current density has been estimated by Bean’s critical state model at different magnetic fields (J
C(H)) and temperatures (J
C(T)) measured for H‖ab-plane and H‖c axis. The anisotropic behaviour has also been observed for J
C(H). The presence of ‘peak effect’ or fishtail characteristic has been noticed in M–H loops for H‖c only, which shows a shift towards the lower fields with increasing temperature. The nature of the pinning mechanisms in the sample has been determined by the normalized pinning force density using the Dew Hughes scaling rule, and the analysis of experimental data indicates the presence of δl-pinning in the sample. The temperature-dependent electronic specific heat has been fitted with the exponential law and the evaluated coupling constant 2Δ0/kBTc
is ∼3.42 which is close to the universal BCS value of 3.53. The observed low value of residual Sommerfeld coefficient

γ

r
e
s

≈ 4.59 mJ mol−1 K2 indicates good quality of the grown single crystal.
Multiple phase transitions in ER edge-coupled interdependent networks
Authors: Gao Yanli , Liu Jun , He Haiwei , Zhou Jie , Chen Shiming 
Published: January 2022

Abstract
Considering the real-world scenarios that there are interactions between edges in different networks and each network has different topological structure and size, we introduce a model of interdependent networks with arbitrary edge-coupling strength, in which q

A
and q

B
are used to represent the edge-coupling strength of network A and network B respectively. A mathematical framework using generating functions is developed based on self-consistent probabilities approach, which is verified by computer simulations. In particular, we carry out this mathematical framework on the Erdös–Rényi edge-coupled interdependent networks to calculate the values of phase transition thresholds and the critical coupling strengths which distinguish different types of transitions. Moreover, as contrast to the corresponding node-coupled interdependent networks, we find that for edge-coupled interdependent networks the critical coupling strengths are smaller, and the critical thresholds as well, which means the robustness of partially edge-coupled interdependent networks is better than that of partially node-coupled interdependent networks. Furthermore, we find that network A will have hybrid percolation behaviors as long as the coupling strength q

A
belongs to a certain range, and the range does not affected by average degree of network A. Our findings may fill the gap of understanding the robustness of edge-coupled interdependent networks with arbitrary coupling strength, and have significant meaning for network security design and optimization.
A direct method to detect deterministic and stochastic properties of data
Authors: Prado Thiago Lima , Boaretto Bruno Rafael Reichert , Corso Gilberto , dos Santos Lima Gustavo Zampier , Kurths Jürgen , Lopes Sergio Roberto 
Published: January 2022

Abstract
A fundamental question of data analysis is how to distinguish noise corrupted deterministic chaotic dynamics from time-(un)correlated stochastic fluctuations when just short length data is available. Despite its importance, direct tests of chaos vs stochasticity in finite time series still lack of a definitive quantification. Here we present a novel approach based on recurrence analysis, a nonlinear approach to deal with data. The main idea is the identification of how recurrence microstates and permutation patterns are affected by time reversibility of data, and how its behavior can be used to distinguish stochastic and deterministic data. We demonstrate the efficiency of the method for a bunch of paradigmatic systems under strong noise influence, as well as for real-world data, covering electronic circuit, sound vocalization and human speeches, neuronal activity, heart beat data, and geomagnetic indexes. Our results support the conclusion that the method distinguishes well deterministic from stochastic fluctuations in simulated and empirical data even under strong noise corruption, finding applications involving various areas of science and technology. In particular, for deterministic signals, the quantification of chaotic behavior may be of fundamental importance because it is believed that chaotic properties of some systems play important functional roles, opening doors to a better understanding and/or control of the physical mechanisms behind the generation of the signals.
Modification of contact properties in Pt/n-GaN Schottky junctions with ZnO and TiO2/ZnO interlayers
Authors: Kim Hogyoung , Jung Myeong Jun , Choi Byung Joon 
Published: January 2022

Abstract
In this study, ZnO (10 nm) and TiO2 (2 nm) were grown on a GaN substrate via atomic layer deposition, and the modified properties of Pt/GaN Schottky diodes with ZnO and ZnO/TiO2 interlayers (ILs) were electrically investigated. The barrier height increased with the ZnO and ZnO/TiO2 ILs; however, the ideality factor increased with the ZnO/TiO2 IL. The reverse-current–voltage characteristics were associated with the Poole–Frenkel emission for all the three junctions. Compared with the Pt/GaN junction, the density of the surface states decreased for the Pt/ZnO/GaN junction but increased for the Pt/ZnO/TiO2/GaN junction. An increase in the ideality factor and a decrease in the barrier height with decreasing temperature were observed at the Pt/GaN and Pt/ZnO/TiO2/GaN junctions. In general, the diode characteristics of the Pt/GaN junction improved owing to the ZnO IL, whereas it degraded owing to the ZnO/TiO2 IL. However, both ZnO and ZnO/TiO2 ILs demonstrate worse diode characteristics at higher temperatures. A thicker ZnO layer (>10 nm) is suggested for improved thermal stability.
Spontaneous emission induced grating in a Rydberg quantum system
Authors: Rezaei Mojtaba , Javidan Kurosh 
Published: January 2022

Abstract
In this paper, we study the electromagnetically induced grating via spontaneous emission induced coherence (SIC) in a four-level quantum system consisting of a Rydberg state. The quantum system interacts with a weak probe light and a strong coupling light with standing wave pattern. We find that under presence of SIC, the amplitude and phase modulations of the medium can be controlled when we tune the detuning of the coupling light. Here, we realize that by tuning the amplitude and phase modulations of the medium, the energy of probe light can be transferred from zero order to high order of grating, respectively. In this case, the switching from amplitude grating to phase grating is possible when we adapt the optical parameters of the medium. Our proposed model may have potential applications in quantum information processing.
Investigating EEG-based functional connectivity patterns for multimodal emotion recognition
Authors: Wu Xun , Zheng Wei-Long , Li Ziyi , Lu Bao-Liang 
Published: January 2022

Abstract

Objective. Previous studies on emotion recognition from electroencephalography (EEG) mainly rely on single-channel-based feature extraction methods, which ignore the functional connectivity between brain regions. Hence, in this paper, we propose a novel emotion-relevant critical subnetwork selection algorithm and investigate three EEG functional connectivity network features: strength, clustering coefficient, and eigenvector centrality. Approach. After constructing the brain networks by the correlations between pairs of EEG signals, we calculated critical subnetworks through the average of brain network matrices with the same emotion label to eliminate the weak associations. Then, three network features were conveyed to a multimodal emotion recognition model using deep canonical correlation analysis along with eye movement features. The discrimination ability of the EEG connectivity features in emotion recognition is evaluated on three public datasets: SEED, SEED-V, and DEAP. Main results. The experimental results reveal that the strength feature outperforms the state-of-the-art features based on single-channel analysis. The classification accuracies of multimodal emotion recognition are

95.08
±
6.42
%

on the SEED dataset,

84.51
±
5.11
%

on the SEED-V dataset, and

85.34
±
2.90
%

and

86.61
±
3.76
%

for arousal and valence on the DEAP dataset, respectively, which all achieved the best performance. In addition, the brain networks constructed with 18 channels achieve comparable performance with that of the 62-channel network and enable easier setups in real scenarios. Significance. The EEG functional connectivity networks combined with emotion-relevant critical subnetworks selection algorithm we proposed is a successful exploration to excavate the information between channels.
Unilateral transfemoral amputees exhibit altered strength and dynamics of muscular co-activation modulated by visual feedback
Authors: Krauskopf T , Lauck T B , Klein L , Beusterien M , Mueller M , Von Tscharner V , Mehring C , Herget G W , Stieglitz T , Pasluosta C 
Published: January 2022

Abstract

Objective. Somatosensory perception is disrupted in patients with a lower limb amputation. This increases the difficulty to maintain balance and leads to the development of neuromuscular adjustments. We investigated how these adjustments are reflected in the co-activation of lower body muscles and are modulated by visual feedback. Approach. We measured electromyography (EMG) signals of muscles from the trunk (erector spinae and obliquus external), and the lower intact/dominant leg (tibialis anterior and medial gastrocnemius) in 11 unilateral transfemoral amputees and 11 age-matched able-bodied controls during 30 s of upright standing with and without visual feedback. Muscle synergies involved in balance control were investigated using wavelet coherence analysis. We focused on seven frequencies grouped in three frequency bands, a low-frequency band (7.56 and 19.86 Hz) representing more sub-cortical and spinal inputs to the muscles, a mid-frequency band (38.26 and 62.63 Hz) representing more cortical inputs, and a high-frequency band (92.90, 129 and 170.90 Hz) associated with synchronizing motor unit action potentials. Further, the dynamics of changes in intermuscular coupling over time were quantified using the Entropic Half-Life. Main results. Amputees exhibited lower coherency values when vision was removed at 7.56 Hz for the muscle pair of the lower leg. At this frequency, the coherency values of the amputee group also differed from controls for the eyes closed condition. Controls and amputees exhibited opposite coherent behaviors with visual feedback at 7.56 Hz. For the eyes open condition at 129 Hz, the coherency values of amputees and controls differed for the muscle pair of the trunk, and at 170.90 Hz for the muscle pair of the lower leg. Amputees exhibited different dynamics of muscle co-activation at the low frequency band when vision was available. Significance. Altogether, these findings point to the development of neuromuscular adaptations reflected in the strength and dynamics of muscular co-activation.
Subdynamics of fluctuations in a many-particle quantum system
Authors: Los Victor F 
Published: January 2022

Abstract
It is shown that the relevant part of an equilibrium two-time correlation function of operators related to a subsystem of S < N particles, selected from the whole system of N ≫ 1 quantum particles, obeys the exact completely closed (homogeneous) evolution equation. This equation differs from the conventional Nakajima–Zwanzig equation by the absence of the undesirable inhomogeneous term comprising all interparticle correlations at the initial time moment. The equation defines the subdynamics in a subspace of S selected particles and is obtained without any use of approximation like the Boltzmann ‘molecular chaos’, factorized initial state or Bogoliubov’s principle of weakening of initial correlations. In the second order in a small inter-particle interaction, this equation reduces to the Markovian evolution equation, which for a one-particle correlation function (S = 1) takes the form of the linear generalized quantum Boltzmann-like equation for a relevant part of a correlation function (one particle momentum distribution function) with the additional terms conditioned by initial correlations taken into account. This equation makes it possible to obtain the solution for the corresponding one-particle correlation function, which is valid for all timescales and reveals the influence of initial correlations on the evolution in time process. On a large timescale t ≫ t
cor ∼ ℏ/k
B
T (decoherence time), the initial correlations cease to influence the damping process and the evolution enters a kinetic stage. However, the factor related to initial correlations survives on the large timescale, and can contribute to the kinetic coefficients.
Short-term reduction of regional enhancement of atmospheric CO2 in China during the first COVID-19 pandemic period
Authors: Sim Sojung , Lee Haeyoung , Oh Eunsil , Kim Sumin , Ciais Philippe , Piao Shilong , Lin John C , Mallia Derek V , Lee Sepyo , Kim Yeon-Hee , Park Hoonyoung , Yun Jeongmin , Jeong Sujong 
Published: January 2022

Abstract
Recent studies have reported a 9% decrease in global carbon emissions during the COVID-19 lockdown period; however, its impact on the variation of atmospheric CO2 level remains under question. Using atmospheric CO2 observed at Anmyeondo station (AMY) in South Korea, downstream of China, this study examines whether the decrease in China’s emissions due to COVID-19 can be detected from the enhancement of CO2 mole fraction (ΔCO2) relative to the background value. The Weather Research and Forecasting–Stochastic Time-Inverted Lagrangian Transport model was applied to determine when the observed mole fractions at AMY were affected by air parcels from China. Atmospheric observations at AMY showed up to a −20% (−1.92 ppm) decrease in ΔCO2 between February and March 2020 compared to the same period in 2018 and 2019, particularly with a −34% (−3.61 ppm) decrease in March. ΔCO, which was analyzed to explore the short-term effect of emission reductions, had a decrease of −43% (−80.66 ppb) during the lockdown in China. Particularly in East China, where emissions are more concentrated than in Northeast China, ΔCO2 and ΔCO decreased by −44% and −65%, respectively. The ΔCO/ΔCO2 ratio (24.8 ppb ppm−1), which is the indicator of emission characteristics, did not show a significant difference before and after the COVID-19 lockdown period (α = 0.05), suggesting that this decrease in ΔCO2 and ΔCO was associated with emission reductions rather than changes in emission sources or combustion efficiency in China. Reduced carbon emissions due to limited human activity resulted in a decrease in the short-term regional enhancement to the observed atmospheric CO2.
Effect of niobium alloying on the austenite grain growth and mechanical properties of ultrahigh-strength stainless steel
Authors: Tian Shuai , Liu Zhenbao , Fu Renli , Wang Xiaohui 
Published: January 2022

Abstract
In the temperature range of 1000 °C–1150 °C and the holding time range of 30–150 min, the effect of niobium (Nb) on the behavior of grain growth and the evolution pattern of the mechanical properties of a martensitic stainless steel was studied. This study found that the addition of Nb allowed a large amount of undissolved NbC phase to be present in the steel, that the dragging effect of the solute atoms such as solute Nb and Mo reduced the migration rate of the grain boundary , and the pinning effect of NbC hindered the growth of grains, and that the growth rate of grains in 0.11Nb steel was slow in the temperature range of 1000 °C–1080 °C and increased significantly at the temperature range of 1080 °C–1150 °C. Next, the kinetic equations of the grain growth of 0.002Nb steel and 0.11Nb steel were constructed. The second phase strengthening of NbC and the fine grain strengthening jointly increased the yield strength of the steel but reduced the plasticity and ultimate tensile strength (UTS) of the steel. The addition of Nb had a minor effect on the content of retained austenite in the steel, but its refining effect on the hierarchical martensite microstructure increased the number of nucleation sites of retained austenite, reduced their sizes, made their distribution more dispersed, and more effectively hindered crack propagation, thus improving the toughness of the steel.
Preparation of magnetic cobalt-cuprum-zinc ferrite nanoparticles and their adsorption mechanism of methyl blue
Authors: Ouyang Hezhong , Pan Shengying , Liu Aihua , Wang Yan , Zang Zhizhong , Liu Yanchun , Liu Dandan 
Published: January 2022

Abstract
Magnetic cobalt-cuprum-zinc ferrites were prepared from anhydrous ethanol using the combustion method, and their structure and properties were characterized using the XRD, SEM, EDS, and VSM techniques, and its formation mechanism was discussed. The magnetic Co0.4Cu0.2Zn0.4Fe2O4 nanoparticles calcined at 400 °C with 25 ml anhydrous ethanol were used for the removal of methyl blue (MB). The results showed that the pseudo-second-order kinetic model best agreed with the adsorption method. In addition, analysis of the adsorption isotherms using the Freundlich, Langmuir, and Temkin models showed that theTemkin model was most consistent with experimental results, which revealed that the adsorption of MB onto the Co0.4Cu0.2Zn0.4Fe2O4 nanoparticles was a multi-molecular layer chemisorption. Further, the influence of pH on the adsorption capacity was evaluated and was highest at pH 11. The cyclability and removal rate of the nanoparticles were explored. The removal rate was approximately 80% after 7 cycles, revealing that the magnetic CoxCuyZn(1-x-y)Fe2O4 nanoparticles are important for wastewater treatment.
Achieving specified geometric quality in a fully printed flexible functional layer using process parameters in roll-to-roll printed electronics
Authors: Jo Minho , Kim Seongyong , Cho Gyoujin , Lee Taik-Min , Lee Jongsu , Lee Changwoo 
Published: January 2022

Abstract
Roll-to-roll (R2R) gravure printing is mainly used in the manufacture of conductive lines or electronic devices because complex patterns can be printed quickly and accurately on flexible substrates using an engraved pattern roll. Gravure printing has several advantages including multi-layer printing of large-area functional layers and continuous production of electronic devices such as thin-film transistors (TFTs) or complex electronic circuits. Existing studies have demonstrated that printing quality can be improved by determining the desired conditions of coating and printing machine without changing the ink and web properties. However, few studies have focused on controlling the geometry of printed patterns and coated layers according to the web tension and web speed, considering spreading effect and ink transfer. In this study, the effects of the controllable parameters in R2R gravure printing, namely web tension and web speed, on the geometry of the gate electrode, dielectric layer, and source–drain electrode of a TFT are examined. We obtained metamodels to estimate the thicknesses and widths of the conductive and dielectric patterns of a printed TFT according to the web tension and speed of a pilot-scale R2R gravure printing machine using design of experiment. The developed metamodels exhibited superior performance, with an average estimation error of 4.18 ± 3.05%. We further analyzed variations in the thickness of the gate electrode and dielectric layer according to fluctuations in the tension in the R2R printing process. Our results show that fluctuations in the tension should be maintained constant to achieve a uniform geometry of the printed pattern. This study demonstrates that the geometry of the printed pattern can be controlled using web tension and web speed, without changing the ink properties.