bluuebunny/crossref_metadata_2025 huggingface dataset:
Energy scales and black hole pseudospectra: the structural role of the scalar product
Authors: Gasperín E , Jaramillo J L
Published: January 2022

A pseudospectrum analysis has recently provided evidence of a potential generic instability of black hole (BH) quasinormal mode (QNM) overtones under high-frequency perturbations. Such instability analysis depends on the assessment of the size of perturbations. The latter is encoded in the scalar product and its choice is not unique. Here, we address the impact of the scalar product choice, advocating for founding it on the physical energy scales of the problem. The article is organized in three parts: basics, applications and heuristic proposals. In the first part, we revisit the energy scalar product used in the hyperboloidal approach to QNMs, extending previous effective analyses and placing them on solid spacetime basis. The second part focuses on systematic applications of the scalar product in the QNM problem: (i) we demonstrate that the QNM instability is not an artifact of previous spectral numerical schemes, by implementing a finite elements calculation from a weak formulation; (ii) using Keldysh’s asymptotic expansion of the resolvent, we provide QNM resonant expansions for the gravitational waveform, with explicit expressions of the expansion coefficients; (iii) we propose the notion of ‘epsilon-dual QNM expansions’ to exploit BH QNM instability in BH spectroscopy, complementarily exploiting both non-perturbed and perturbed QNMs, the former informing on large scales and the latter probing small scales. The third part enlarges the conceptual scope of BH QNM instability proposing: (a) spiked perturbations are more efficient in triggering BH QNM instabilities than smooth ones, (b) a general picture of the BH QNM instability problem is given, supporting the conjecture (built on Burnett’s conjecture on the spacetime high-frequency limit) that Nollert–Price branches converge universally to logarithmic Regge branches in the high-frequency limit and (c) aiming at a fully geometric description of QNMs, BMS states are hinted as possible asymptotic/boundary degrees of freedom for an inverse scattering problem.
Covariance kernels investigation from diffusive wave equations for data assimilation in hydrology
Authors: Malou T , Monnier J
Published: January 2022

In data assimilation (DA), the estimation of the background error covariance operator is a classical and still open topic. However, this operator is often modeled using empirical information. In order to exploit at best the potential of the knowledge of the physics, the present study proposes a method to derive covariance operators from the underlying equations. In addition, Green’s kernels can be used to model covariance operators and are naturally linked to them. Therefore, Green’s kernels of equations representing physics can provide physically-derived estimates of the background error covariance operator, and also physically-consistent parameters. In this context, the present covariance operators are used in a variational DA (VDA) process of altimetric data to infer bathymetry in the Saint-Venant equations. In order to investigate these new physically-derived covariance operators, the associated VDA results are compared to the VDA results using classical operators with physically-consistent and arbitrary parameters. The physically-derived operators and physically-consistent exponential operator provide better accuracy and faster convergence than empirical operators, especially during the first iterations of the VDA optimization process.
Experimental investigation on the velocity of cathode spots in a vacuum arc with high di/dt
Authors: Liu Liming , Yuan Zhao , Chen Lixue , Liu Shan
Published: January 2022

With the development of DC transmission and aerospace technology, the demands on the breaking capacity of vacuum circuit breakers (VCBs) under high

d

i

d

t

condition are getting higher and higher. The breaking capacity of VCBs is determined by cathode spots, which provide electrons and metal vapor to maintain the arc. In this paper, the experiments of cathode spot observation were carried out based on the detachable vacuum interrupter and the cup-shaped axial magnetic field contacts. The images of cathode spot distribution were obtained by an ultra high-speed camera. In the initial expansion stage of arcing, it was discovered that the distribution of cathode spots is ring-shaped and symmetrical. The initial expansion velocity of cathode spot ring is approximately proportional to the value of

d

i

d

t

and is independent of frequency. During the whole arcing process, the expansion velocity of cathode spot ring rises first and then drops with arcing time. The effects of the magnetic field and metal vapor density on the expansion process of cathode spot were analyzed. Based on the experimental conditions and results, the values of magnetic field and metal vapor density were calculated which can reasonably explain the variation of expansion velocity of cathode spot.
Nonlinearly tunable extraordinary optical transmission in a hybird metamaterial
Authors: Cai Weiqi , Fan Yuancheng , Fu Quanhong , Yang Ruisheng , Zhu Wei , Zhang Yujing , Zhang Fuli
Published: January 2022

Dielectric metamaterials are promising for significantly enhanced optical nonlinearity for their strongly localized Mie-resonant mode. Here, we theoretically and experimentally studied a hybrid metamaterial exhibiting extraordinary optical transmission (EOT) behavior, in which the transmission amplitude and frequency can be modulated. The EOT of the perforated metal sheet with subwavelength aperture is induced with a dielectric cuboid by setting them in a close proximity and exploiting the first-order Mie-resonant mode. The electromagnetic wave is effectively coupled to the subwavelength aperture by properly placing the dielectric cuboid, and the transmission intensity can be enhanced more than 150 times. Meanwhile, we employed the nonlinear effect of the dielectric cuboid to modulate the operation band of the EOT. Hopefully, our work can inspire innovations for the research of light–matter interactions, electromagnetic light switching devices and filter devices.
Research and application of a novel piecewise unsaturated asymmetric tristable stochastic resonance system
Authors: Zhang Gang , Zhu Xingyu , Zhang Tianqi
Published: January 2022

Early fault diagnosis of rolling bearings is of great significance in the application of mechanical equipment, which makes the extraction of weak fault signals particularly critical by stochastic resonance (SR). Compared with bistable SR, tristable SR has stronger advantages in weak signal extraction, but the classical tristable stochastic resonance (CTSR) system was limited by output saturation, which resulted in insufficient signal amplification ability. To solve the above problems, combined with asymmetric system whose output can be improved to a higher degree, a novel piecewise unsaturated asymmetric tristable SR (NPUATSR) system is proposed. Through numerical simulation, it is concluded that NPUATSR output amplitude varies proportionally with the amplitude of the input, which overcomes the output saturation of CTSR. Secondly, the stationary probability density and mean first passage time of particles are derived by using adiabatic approximation theory, and the variation law caused by parameters is analyzed in combination with potential function, the internal mechanism of the system is further studied. Through the output signal-to-noise ratio (SNR), it is found that the performance advantage of NPUTASR system is the most obvious, and different parameters affect the output SNR. Finally, the adaptive genetic algorithm is used to optimize the parameters, and the proposed system is applied to early fault diagnosis on different types of bearings. After comparison with different systems, the results show that NPUATSR can effectively detect the fault frequency, and has the most outstanding advantages in spectrum amplification and anti-noise performance, which proves that NPUATSR system has significant value in practical engineering application.
Combination of selol nanocapsules and magnetic hyperthermia hinders breast tumor growth in aged mice after a short-time treatment
Authors: Pinheiro Willie Oliveira , Costa do Santos Mayara Simonelly , Farias Gabriel Ribeiro , Fascineli Maria Luiza , Ramos Khellida Loiane Vieira , Duarte Eliza Carla Barroso , Damasceno Emanuel Adelino Medeiros , da Silva Jaqueline Rodrigues , Joanitti Graziella Anselmo , de Azevedo Ricardo Bentes , Sousa Marcelo Henrique , Lacava Zulmira Guerrero Marques , Mosiniewicz-Szablewska Ewa , Suchocki Piotr , Morais Paulo Cesar , de Andrade Laise Rodrigues
Published: January 2022

Short time treatment with reduced dosages of selol-loaded PLGA nanocapsules (NcSel) combined with magnetic hyperthermia (MHT) is evaluated in aged Erhlich tumor-bearing mice. Clinical, hematological, biochemical, genotoxic and histopathological parameters are assessed during 7 d treatment with NcSel and MHT, separately or combined. The time evolution of the tumor volume is successfully modeled using the logistic mathematical model. The combined therapy comprising NcSel and MHT is able to hinder primary tumor growth and a case of complete tumor remission is recorded. Moreover, no metastasis was diagnosed and the adverse effects are negligible. NcSel plus MHT may represent an effective and safe alternative to cancer control in aged patients. Future clinical trials are encouraged.
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

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

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

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

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

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

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

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

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

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

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

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

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

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.
Preparation of large-area, high-performance single-walled carbon nanotube (SWCNT)-based heater films by roll-to-roll gravure printing
Authors: Zhang Qin , Ren Yunfei , Wang Zhenguo , Chen Xiaolian , Portilla Luis , Sun Litao , Zhang Dongyu , Zhao Jianwen
Published: January 2022

In this work, we have developed an eco-friendly and fast method for the preparation of large-area high-performance single-walled-carbon-nanotube (SWCNT)-based conductive thin films on polyethylene terephthalate substrates by roll-to-roll (R2R) gravure printing technology. Large-area (16 cm × 32 cm) conductive films, consisting of SWCNT or SWCNT/silver nanowire (AgNW) films, were fabricated for the first time by R2R gravure printing technique. The conductivity, transmittance, mechanical flexibility and heating ability were evaluated in detail. For example, the square resistances of the SWCNT thin film and SWCNT/AgNW composite film were 69.92 and 17.44 Ω/□ and the optical transmittance at a wavelength of 550 nm were 50.70% and 66.77%, respectively. Meanwhile, the prepared SWCNT and SWCNT/AgNW composite films exhibit excellent heating stability, temperature uniformity and resistance to bending. The composite films can withstand 6000 bending cycles at a curvature radius of 3.5 mm and obtain a temperature of up to 100 °C with a low driving voltage (6 V), a fast heating response (within 15 s) and heating rate (about 4.933 °C s−1). These properties reflect the potential of SWCNTs in improving the mechanical and heating properties of composite films, which are promising for low power, large area, flexible and customizable electronic devices.
Influence of multi-timescale precipitation indices on primary tea production in Baoshan, Yunnan, China
Authors: Li Shaojuan , Lu Jun , Pope Edward , Golding Nicola , Zhou Tianjun , Li Fazhi , Duan Wei
Published: January 2022

The regional economy in Yunnan, Southwest China, relies heavily on tea production. Both the quality and amount of tea production are sensitive to extreme climate events, but exactly how different timescale climate events influence tea production remains unknown. In this study, we explore the dynamic responses of tea production indices in Baoshan, Yunnan to 6 multi-timescale precipitation indices (MPIs) at lags of up to 20 years. The results are as follows: (1) Wet injury caused by precipitation during summer and autumn is a prominent threat to annual tea production in Baoshan, which leads to negative impacts on annual tea yield and raw tea price, with the impact on the latter mainly reflected in tea quality during the primary processing for black tea and green tea. (2) Annual tea yield and raw tea price are negatively correlated with CDD (consecutive dry days) and R20 (very heavy precipitation days) at lags greater than one year. (3) Spring tea yield and raw tea price are negatively correlated with spring precipitation, but positively correlated with days in the winter-spring dormancy period of tea plant (WSDP) and precipitation in WSDP; the positive correlation of days in WSDP is the most prominent with spring tea production of the 3 MPIs. (4) Unlike other famous tea areas, lower R20 frequency in Baoshan is not associated with high rates of soil erosion, but the lack of drainage ditches in the tea garden still means that continuous precipitation or heavy rainfall are a risk to Baoshan tea production. The insights provided by this study will help farmers and other decision-makers to understand the mechanism of MPIs’ influence on tea production, inform regional responses in tea plantation management to the observed different precipitation trends, and improve future management decisions under a changing climate.
Improving coastal and marine resources management through a co-management approach: a case study of Pakistan
Authors: Ullah Zafar , Wu Wen , Wang Xiao Hua , Pervez Rashid , Ahmed Aziz , Baloch Amdadullah
Published: January 2022

Co-management is a system in which resource management responsibilities are shared between the state and user groups. Various national and provincial-level governments separately manage resources along the coastal and marine areas of Pakistan. The country’s existing policy framework is devoid of an integrated management approach, where the participation of real stakeholders in the decision-making process is either disregarded or missing. Therefore, the present study highlights the internal and external constraints of coastal and marine resources management issues in Pakistan and discourses the problems that halt the participation of stakeholders in the decision-making process. This research also confers the potential of a co-management framework through which the coastal and marine resources management structure can be organized to deliver local sustainability in the country. The adoption of a co-management approach in Pakistan’s coastal and marine areas would help to improve the protection and conservation of natural resources via share-based responsibility. Additionally, it provides a baseline to coastal and marine planners in the country to adopt share-based responsibility for resources management to mimic the conflicts amongst users to the environment, and those affected by the decisions can agree to understand or accept common intertwined resources.
Gaps in the knowledge of thyroid hormones and placental biology
Authors: Carvalho Daniela Pereira , Dias Ariane Fontes , Sferruzzi-Perri Amanda Nancy , Ortiga-Carvalho Tania Maria
Published: January 2022

Thyroid hormones (THs) are required for the growth and development of the fetus, stimulating anabolism, and oxygen consumption from the early stages of pregnancy to the period of fetal differentiation close to delivery. Maternal changes in the hypothalamic–pituitary–thyroid axis are also well known. In contrast, several open questions remain regarding the relationships between the placenta and the maternal and fetal TH systems. The exact mechanism by which the placenta participates in regulating the TH concentration in the fetus and mother and the role of TH in the placenta are still poorly studied. In this review, we aim to summarize the available data in the area and highlight significant gaps in our understanding of the ontogeny and cell-specific localization of TH transporters, TH receptors, and TH metabolic enzymes in the placenta in both human and rodent models. Significant deficiencies also exist in the knowledge of the contribution of genomic and nongenomic effects of TH on the placenta and finally, how the placenta reacts during pregnancy when the mother has thyroid disease. By addressing these key knowledge gaps, improved pregnancy outcomes and management of women with thyroid alterations may be possible.
Need for Knowledge—What, Where and How? How Social Workers Handle Service and Support for Individuals with Disability
Authors: Nordgren Camilla , Anderson Lotta , Lingärde Svante , Runesson Ingrid , Staaf Annika
Published: January 2022

This article investigates the need and sources of knowledge among LSS administrators in Sweden (i.e. social workers handling service and support for individuals with disability according to the Swedish Disability Act [LSS]). Changing and challenging working conditions and issues concerning professional status warrant the aim. A questionnaire distributed via gatekeepers in a number of municipalities demonstrated that knowledge about ‘disability’, ‘law’, ‘ethics’ and ‘augmentative and alternative communication’ was rated highly. This result is particularly interesting given that many social work education programmes do not have compulsory courses in disability. Colleagues appear to be relied upon as essential sources of support and knowledge, but the knowledge sharing seems unorganised. Findings are discussed in relation to communities of practice (CoP) and shows that, due to the lack of essential knowledge from formal education and the strong dependence on colleagues, a locally developed praxis might be established. Inadequate theoretical and research-based knowledge, together with this local praxis knowledge, may result in the LSS administrators’ work becoming inadequate. A specialist education in disability studies is proposed as a prerequisite for being employed as an LSS administrator, and the inclusion of a theoretical and scientific framework in the regular CoP interaction is also recommended.
Efficacy, Safety, Pharmacokinetics, and Microbiome Changes of Ibezapolstat in Adults with Clostridioides difficile Infection: A Phase 2a Multicenter Clinical Trial
Authors: Garey Kevin W , McPherson Jacob , Dinh An Q , Hu Chenlin , Jo Jinhee , Wang Weiqun , Lancaster Chris K , Gonzales-Luna Anne J , Loveall Caroline , Begum Khurshida , Jahangir Alam M , Silverman Michael H , Hanson Blake M
Published: January 2022

Background

This study was the first human validation of the gram-positive bacterial DNA polymerase IIIC target in patients with Clostridioides difficile infection. The primary objectives were to assess clinical cure rates and adverse events (AEs). Secondary objectives were to evaluate plasma/fecal pharmacokinetics, microbiologic eradication, microbiome and bile acid effects, and sustained clinical cure (SCC) with ibezapolstat.

Methods

This single-arm, open-label, phase 2a study enrolled adults with C. difficile infection at 4 US centers. Patients received ibezapolstat 450 mg orally every 12 hours for 10 days and followed for an additional 28 days to assess study objectives.

Results

Ten patients with a mean (standard deviation [SD]) age of 49 [15] years were enrolled. Seven AEs were reported classified as mild-moderate. Plasma levels of ibezapolstat ranged from 233 to 578 ng/mL while mean (SD) fecal levels were 416 (494) µg/g stool by treatment day 3 and >1000 µg/g stool by days 8–10. A rapid increase in alpha diversity in the fecal microbiome was noted after starting ibezapolstat therapy, which was maintained after completion of therapy. A proportional decrease in Bacteroidetes phylum was observed (mean change [SD], −10.0% [4.8%]; P = .04) with a concomitantly increased proportion of Firmicutes phylum (+14.7% [5.4%]; P = .009). Compared with baseline, total primary bile acids decreased by a mean (SD) of 40.1 (9.6) ng/mg stool during therapy (P < .001) and 40.5 (14.1) ng/mg stool after completion of therapy (P = .007). Rates of both initial clinical cure and SCC at 28 days were 100% (10 of 10 patients).

Conclusions

In this phase 2a study, 10 of 10 patients achieved SCC, demonstrated favorable pharmacokinetics, minimal AEs, and beneficial microbiome and bile acids results. These results support continued clinical development.
Role of Nutrient-sensing Receptor GPRC6A in Regulating Colonic Group 3 Innate Lymphoid Cells and Inflamed Mucosal Healing
Authors: Hou Qihang , Huang Jingxi , Xiong Xia , Guo Yuming , Zhang Bingkun
Published: January 2022

Background and Aims

Group 3 innate lymphoid cells [ILC3s] sense environmental signals and are critical in gut homeostasis and immune defence. G-protein-coupled receptors [GPCRs] mediate cellular responses to diverse environmental signals. However, the GPCRs’ regulation mechanisms of ILC3s is largely unknown.

Methods

We used wild-type [WT] and GPRC6A-/- mice to investigate the role of GPRC6A in the population and the function of ILC3s. We then purified ILC3s from WT and GPRC6A-/- mice. Colitis was induced in WT mice and GPRC6A-/- mice through dextran sodium sulphate [DSS] administration or C. rodentium infection. Furthermore L-arginine, a selective GPRC6A agonist, was administered to mice with colitis.

Results

We found that colonic ILC3s expressed GPRC6A. The deficiency of GPRC6A decreased ILC3-derived interleukin-22 [IL-22] production and the number of proliferating ILC3s, which led to increased susceptibility to colon injury and pathogen infection and impaired inflamed mucosal healing. Further studies showed that L-arginine, a GPRC6A agonist, promoted colonic ILC3 expansion and function via the mammalian target of rapamycin complex 1 [mTORC1] signalling in vitro. In addition, L-arginine attenuated DSS-induced colitis in vivo. This was associated with a significant increase in IL-22 secretion by ILC3s.

Conclusions

Our findings unveil a role for the nutrient-sensing receptor GPRC6A in colonic ILC3 function and identify a novel ILC3 receptor signalling pathway modulating inflamed mucosal healing.
Quaker Outcasts and the Creation of Missionary Anglicanism, 1691–1706
Authors: Finnegan Oliver
Published: January 2022

This article re-examines the creation and implications of missionary Anglicanism during the later 1690s. It focuses on a small group of Quaker outcasts and their role in the creation of the Society for the Propagation of the Gospel, as well as their continuing influence during the institution’s earliest years. An initial Anglican missionary impulse was stimulated and directed by the belated realisation among ministers that, since the 1670s, the Society of Friends had expanded rapidly in the Americas. Seeking strategies for how they might respond to this growth of organised dissent, Anglicans turned to those who had been cast out of the Society of Friends on both sides of the ocean. In particular, they sought the aid of George Keith, who had been disowned by the Quakers because of the schism he caused in Pennsylvania during 1692. These outcasts came to serve as confessional intermediaries, importing specifically Quaker techniques of missionary tours, networking and the usage of cheap print into the Society for the Propagation of the Gospel. Their actions also had further, parallel consequences across the Atlantic. The division Keith caused and the activities of the outcasts thereafter encouraged a reformation of Quakerism, the formation of Anglican networks and the first soundings of a transoceanic public sphere. Being neither Quakers nor truly Anglicans, but entangled with both, the outcasts fomented strife between these two faiths. However, they also promoted ecclesiological reaction and borrowing between them, which, in turn, catalysed processes of Atlantic confession-building and opened a transatlantic dimension in anglophone debates around religiosity.
‘You Can’t have a One Size Fits all Strategy in Translation’: An Interview with Fakrul Alam
Authors: Islam Mohammad Shafiqul
Published: January 2022

Fakrul Alam, an academic, editor, essayist, and critic, is one of the leading translators of Bengali literature. With more than four decades of teaching experience at Dhaka University, Bangladesh, where he is currently Director of Bangabandhu Sheikh Mujib Research Institute for Peace and Liberty, he has contributed widely to research and translation. His areas of research include, among others, colonial and postcolonial literatures, South Asian literature, and translation studies. Well known as a translator of Jibanananda Das (1899–1954), a great poet of Bengali literature, and Rabindranath Tagore (1861–1941), a Nobel Prize winning poet and writer, Alam has also translated works of various genres, including nonfiction and song-lyrics. His translations of the works of Sheikh Mujibur Rahman, the Father of the Nation, famously called ‘Bangabandhu,’ Friend of Bengal, are remarkable and internationally acclaimed. In this interview, Alam has given an account of his rich body of translated works as well as his motivations to venture into translation. Moreover, he has addressed various issues of translation and translation studies along with his long journey as a translator from a postcolonial nation like Bangladesh. The interview, above all, focuses on Alam’s career as a translator, his reflections on literary translation, the challenges and prospects of Bengali literature in translation into English, his own individual strategies and techniques of translation, and his current and future translation projects. The interview was conducted online during March and April 2021.