bluuebunny/crossref_metadata_2025 huggingface dataset:
Phallus impudicus
. [Descriptions of Fungi and Bacteria].
Authors: Minter D. W. , Soliman G. S.
Published: January 2022

A description is provided for
Phallus impudicus
. Some information on its morphological characteristics, associated organisms and substrata, dispersal and transmission, economic impacts, habitats and conservation status is given, along with details of its geographical distribution (Africa (Algeria, Liberia, Morocco, South Africa, Tanzania, Zimbabwe), Asi (Armenia, China, Anhui, Guangdong, Hainan, Hebei, Shanxi, Georgia, India, Assam, Jammu and Kashmir, Maharashtra, Uttar Pradesh, Iran, Israel, Japan, Kazakhstan, Kyrgyzstan, Malaysia, Myanmar, Nepal, Papua New Guinea, Russia, South Korea, Syria, Taiwan, Turkey, Vietnam), Atlantic Ocean (Spain, Islas Canarias), Australasia (Australia, Northern Territory, Queensland, New Zealand), Caribbean (Cuba, Jamaica, Puerto Rico), Central America (Costa Rica, Panama), Europe (Åland Islands, Andorra, Austria, Belarus, Belgium, Bulgaria, Croatia, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Isle of Man, Italy, Jersey, Latvia, Lithuania, Luxembourg, Netherlands, Norway, Poland, Portugal, Romania, Russia, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Ukraine, UK), North America (Canada, Alberta, British Columbia, New Brunswick, Nova Scotia, Ontario, Prince Edward Island, Quebec, Saskatchewan, Mexico, USA, Alabama, Arizona, Arkansas, California, Colorado, Connecticut, Delaware, District of Columbia, Florida, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Nebraska, Nevada, New Hampshire, New Jersey, New Mexico, New York, North Carolina, North Dakota, Ohio, Oregon, Pennsylvania, South Carolina, South Dakota, Tennessee, Texas, Utah, Vermont, Virginia, Washington, Wisconsin), Pacific Ocean (Samoa), South America (Brazil, Amazonas, Paraíba, Rio Grande do Norte, Rio Grande do Sul, São Paulo, Chile, Colombia, Guyana, Uruguay)).
Regulating peroxisome–ER contacts via the ACBD5-VAPB tether by FFAT motif phosphorylation and GSK3β
Authors: Kors Suzan , Hacker Christian , Bolton Chloe , Maier Renate , Reimann Lena , Kitchener Emily J.A. , Warscheid Bettina , Costello Joseph L. , Schrader Michael
Published: January 2022

Peroxisomes and the endoplasmic reticulum (ER) cooperate in cellular lipid metabolism. They form membrane contacts through interaction of the peroxisomal membrane protein ACBD5 (acyl-coenzyme A–binding domain protein 5) and the ER-resident protein VAPB (vesicle-associated membrane protein–associated protein B). ACBD5 binds to the major sperm protein domain of VAPB via its FFAT-like (two phenylalanines [FF] in an acidic tract) motif. However, molecular mechanisms, which regulate formation of these membrane contact sites, are unknown. Here, we reveal that peroxisome–ER associations via the ACBD5-VAPB tether are regulated by phosphorylation. We show that ACBD5-VAPB binding is phosphatase-sensitive and identify phosphorylation sites in the flanking regions and core of the FFAT-like motif, which alter interaction with VAPB—and thus peroxisome–ER contact sites—differently. Moreover, we demonstrate that GSK3β (glycogen synthase kinase-3 β) regulates this interaction. Our findings reveal for the first time a molecular mechanism for the regulation of peroxisome–ER contacts in mammalian cells and expand the current model of FFAT motifs and VAP interaction.
CD116+ fetal precursors migrate to the perinatal lung and give rise to human alveolar macrophages
Authors: Evren Elza , Ringqvist Emma , Doisne Jean-Marc , Thaller Anna , Sleiers Natalie , Flavell Richard A. , Di Santo James P. , Willinger Tim
Published: January 2022

Despite their importance in lung health and disease, it remains unknown how human alveolar macrophages develop early in life. Here we define the ontogeny of human alveolar macrophages from embryonic progenitors in vivo, using a humanized mouse model expressing human cytokines (MISTRG mice). We identified alveolar macrophage progenitors in human fetal liver that expressed the GM-CSF receptor CD116 and the transcription factor MYB. Transplantation experiments in MISTRG mice established a precursor–product relationship between CD34−CD116+ fetal liver cells and human alveolar macrophages in vivo. Moreover, we discovered circulating CD116+CD64−CD115+ macrophage precursors that migrated from the liver to the lung. Similar precursors were present in human fetal lung and expressed the chemokine receptor CX3CR1. Fetal CD116+CD64− macrophage precursors had a proliferative gene signature, outcompeted adult precursors in occupying the perinatal alveolar niche, and developed into functional alveolar macrophages. The discovery of the fetal alveolar macrophage progenitor advances our understanding of human macrophage origin and ontogeny.
Soft gluon fields and anomalous magnetic moment of muon
Authors: Nedelko Sergei , Nikolskii Aleksei , Voronin Vladimir
Published: January 2022

An impact of nonperturbatively treated soft gluon modes on the value of anomalous magnetic moment of muon a

μ
is studied within the mean-field approach to QCD vacuum and hadronization. It is shown that radial excitations of vector mesons strongly enhance contribution of hadronic vacuum polarization to a

μ
, doubling the contribution of one-meson processes compared to the result for ground state mesons. The mean field also strongly influences the hadronic light-by-light scattering contribution due to the Wilson line in quark propagators.
Monte Carlo simulations of two-component Coulomb gases applied in surface electrodes
Authors: Salazar Robert , Bayona-Roa Camilo , Téllez Gabriel
Published: January 2022

In this work, we study the gapped surface electrode (SE), a planar system composed of two-conductor flat regions at different potentials with a gap

G

between both sheets. The computation of the electric field and the surface charge density requires solving Laplace’s equation subjected to Dirichlet conditions (on the electrodes) and Neumann boundary conditions over the gap. In this document, the gapless surface electrode is modeled as a two-dimensional classical Coulomb gas having punctual charges +q and −q on the inner and outer electrodes, respectively, interacting with an inverse power law 1/r-potential. The coupling parameter Γ between particles inversely depends on temperature and is proportional to q
2. Precisely, the density charge arises from the equilibrium states via Monte Carlo (MC) simulations. We focus on the coupling and the gap geometry effect. Mainly on the distribution of particles in the circular and the harmonically-deformed gapped SE. MC simulations differ from electrostatics in the strong coupling regime. The electrostatic approximation and the MC simulations agree in the weak coupling regime where the system behaves as two interacting ionic fluids. That means that temperature is crucial in finite-size versions of the gapped SE where the density charge cannot be assumed fully continuous as the coupling among particles increases. Numerical comparisons are addressed against analytical descriptions based on an electric vector potential approach, finding good agreement.
Neutron powder diffraction study of the phase transitions in deuterated methylammonium lead iodide
Authors: Liu Jiaxun , Du Juan , Phillips Anthony E , Wyatt Peter B , Keen David A , Dove Martin T
Published: January 2022

We report the results of a neutron powder diffraction study of the phase transitions in deuterated methylammonium lead iodide, with a focus on the system of orientational distortions of the framework of PbI6 octahedra. The results are analysed in terms of symmetry-adapted lattice strains and normal mode distortions. The higher-temperature cubic–tetragonal phase transition at 327 K is weakly discontinuous and nearly tricritical. The variations of rotation angles and spontaneous strains with temperature are consistent with a standard Landau theory treatment. The lower-temperature transition to the orthorhombic phase at 165 K is discontinuous, with two systems of octahedral rotations and internal distortions that together can be described by 5 order parameters of different symmetry. In this paper we quantify the various symmetry-breaking distortions and their variation with temperature, together with their relationship to the spontaneous strains, within the formalism of Landau theory. A number of curious results in the low-temperature phase are identified, particularly regarding distortion amplitudes that decrease rather than increase with lowering temperature.
Examination of applicability of the ISO slab phantom as calibration phantom for the new ICRU 95 operational quantity personal dose
Authors: Merza Victor , Hranitzky Christian , Steurer Andreas , Maringer Franz Josef
Published: January 2022

In this article, the proposal of the International Commission on Radiation Units and Measurements/International Commission on Radiological Protection (ICRU/ICRP), that the ISO slab phantom should continue to be used as a calibration phantom for the new ICRU Report 95 operational quantity personal dose should be legitimised by simulation and performance of experiments to determine backscatter factors on the ISO slab phantom and, in comparison, on an anthropomorphic Alderson Rando phantom. The scope of this work was restricted to the photon energy range of radiation qualities commonly used in x-ray diagnostics. For this purpose, a shadow-free diagnostic (SFD) ionisation chamber was used to measure backscatter factors for X radiation in the energy range of 24 keV to 118 keV. The Monte Carlo code MCNP 6.2 was used to validate measurement results on the ISO slab phantom. Additionally, the influence of varying the SFD position on the Rando phantom on the backscatter factor was determined. Since backscatter factors on the ISO slab phantom differ only up to

±

5% from those on the Rando phantom, it could be concluded that it is not necessary to develop a new phantom for calibrations in terms of personal dose. A position variation of the detector by a few centimeters on the surface of the Rando phantom causes similarly large deviations and thus alone represents an equally large uncertainty contribution in practical personal dosimetry than that arising from the dissimilarity of the real human body to the ISO slab phantom.
An iterative image-based inter-frame motion compensation method for dynamic brain PET imaging
Authors: Sun Tao , Wu Yaping , Bai Yan , Wang Zhenguo , Shen Chushu , Wang Wei , Li Chenwei , Hu Zhanli , Liang Dong , Liu Xin , Zheng Hairong , Yang Yongfeng , Wang Meiyun
Published: January 2022

As a non-invasive imaging tool, positron emission tomography (PET) plays an important role in brain science and disease research. Dynamic acquisition is one way of brain PET imaging. Its wide application in clinical research has often been hindered by practical challenges, such as patient involuntary movement, which could degrade both image quality and the accuracy of the quantification. This is even more obvious in scans of patients with neurodegeneration or mental disorders. Conventional motion compensation methods were either based on images or raw measured data, were shown to be able to reduce the effect of motion on the image quality. As for a dynamic PET scan, motion compensation can be challenging as tracer kinetics and relatively high noise can be present in dynamic frames. In this work, we propose an image-based inter-frame motion compensation approach specifically designed for dynamic brain PET imaging. Our method has an iterative implementation that only requires reconstructed images, based on which the inter-frame subject movement can be estimated and compensated. The method utilized tracer-specific kinetic modelling and can deal with simple and complex movement patterns. The synthesized phantom study showed that the proposed method can compensate for the simulated motion in scans with 18F-FDG, 18F-Fallypride and 18F-AV45. Fifteen dynamic 18F-FDG patient scans with motion artifacts were also processed. The quality of the recovered image was superior to the one of the non-corrected images and the corrected images with other image-based methods. The proposed method enables retrospective image quality control for dynamic brain PET imaging, hence facilitating the applications of dynamic PET in clinics and research.
Screening of magnetic fields by superconducting and hybrid shields with a circular cross-section
Authors: Gozzelino Laura , Fracasso Michela , Solovyov Mykola , Gömöry Fedor , Napolitano Andrea , Gerbaldo Roberto , Ghigo Gianluca , Laviano Francesco , Torsello Daniele , Grigoroscuta Mihai A , Aldica Gheorghe , Burdusel Mihail , Badica Petre
Published: January 2022

The use of superconducting (SC) materials is crucial for shielding quasi-static magnetic fields. However, the need for space-saving solutions with high shielding performance requires the development of a three-dimensional (3D) modelling procedure capable of predicting the screening properties for different orientations of the applied field. In this paper, we use a 3D numerical model based on a vector potential formulation to investigate the shielding ability of SC screens with cylindrical symmetry and a height/diameter aspect ratio close to unity, without and with the superimposition of a ferromagnetic (FM) circular shell. The chosen materials were MgB2 and soft iron. First, the outcomes of the calculations were compared with the experimental data obtained with different shielding arrangements, achieving a notable agreement in both axial field (AF) and transverse field (TF) orientations. Then, we used this validated modelling approach to investigate how the magnetic mitigation properties of a cup-shaped SC bulk can be improved by the superimposition of a coaxial FM cup. Calculations highlighted that the FM addition is very efficient in enhancing the shielding factors (SFs) in the TF orientation. Assuming a working temperature of 30 K and using a layout with the FM cup protruding over the SC one, SFs up to eight times greater than those with a single SC cup were attained at applied field up to 0.15 T, reaching values equal to or higher than 102 in the inner half of the shield. In the AF orientation, the addition of the same FM cup incurs a modest worsening at low fields, but at the same time it widens the applied field range where SF ⩾ 104 occurs near the close extremity of the shield to over 1 T.
Robustness of two-qubit and three-qubit states in correlated quantum channels
Authors: Wang Zhan-Yun , Wu Feng-Lin , Peng Zhen-Yu , Liu Si-Yuan
Published: January 2022

We investigate how the correlated actions of quantum channels affect the robustness of entangled states. We consider the Bell-like state and random two-qubit pure states in the correlated depolarizing, bit flip, bit-phase flip, and phase flip channels. It is found that the robustness of two-qubit pure states can be noticeably enhanced due to the correlations between consecutive actions of these noisy channels, and the Bell-like state is always the most robust one. We also consider the robustness of three-qubit pure states in correlated noisy channels. For the correlated bit flip and phase flip channels, the result shows that although the most robust and most fragile states are locally unitary equivalent, they exhibit different robustness in different correlated channels, and the effect of channel correlations on them is also significantly different. However, for the correlated depolarizing and bit-phase flip channels, the robustness of two special three-qubit pure states is exactly the same. Moreover, compared with the random three-qubit pure states, they are neither the most robust states nor the most fragile states.
Negative self-feedback induced enhancement and transition of spiking activity for class-3 excitability
Authors: Li Li , Zhao Zhiguo , Gu Huaguang
Published: January 2022

Post-inhibitory rebound (PIR) spike, which has been widely observed in diverse nervous systems with different physiological functions and simulated in theoretical models with class-2 excitability, presents a counterintuitive nonlinear phenomenon in that the inhibitory effect can facilitate neural firing behavior. In this study, a PIR spike induced by inhibitory stimulation from the resting state corresponding to class-3 excitability that is not related to bifurcation is simulated in the Morris–Lecar neuron. Additionally, the inhibitory self-feedback mediated by an autapse with time delay can evoke tonic/repetitive spiking from phasic/transient spiking. The dynamical mechanism for the PIR spike and the tonic/repetitive spiking is acquired with the phase plane analysis and the shape of the quasi-separatrix curve. The result extends the counterintuitive phenomenon induced by inhibition to class-3 excitability, which presents a potential function of inhibitory autapse and class-3 neuron in many neuronal systems such as the auditory system.
Design optimization of broadband extreme ultraviolet polarizer in high-dimensional objective space
Authors: Kuang Shang-Qi , Li Bo-Chao , Wang Yi , Gong Xue-Peng , Lin Jing-Quan
Published: January 2022

With the purpose of designing the extreme ultraviolet polarizer with many objectives, a combined application of multi-objective genetic algorithms is theoretically proposed. Owing to the multi-objective genetic algorithm, the relationships between different designing objectives of extreme ultraviolet polarizer have been obtained by analyzing the distribution of nondominated solutions in the four-dimensional objective space, and the optimized multilayer design can be obtained by guiding the searching in the desired region based on the multi-objective genetic algorithm with reference direction. Compared with the conventional method of multilayer design, our method has a higher probability of achieving the optimal multilayer design. Our work should be the first research in optimizing the optical multilayer designs in the high-dimensional objective space, and our results demonstrate a potential application of our method in the designs of optical thin films.
Study on divertor plasma behavior through sweeping strike point in new lower divertor on EAST
Authors: Tao Yu-Qiang , Xu Guo-Sheng , Meng Ling-Yi , Liang Rui-Rong , Yu Lin , Liu Xiang , Yan Ning , Yang Qing-Quan , Lin Xin , Wang Liang
Published: January 2022

A series of L-mode discharges have been conducted in the new ‘corner slot’ divertor on the Experimental Advanced Superconducting Tokamak (EAST) to study the divertor plasma behavior through sweeping strike point. The plasma control system controls the strike point sweeping from the horizontal target to the vertical target through poloidal field coils, with keeping the main plasma stability. The surface temperature of the divertor target cools down as the strike point moves away, indicating that sweeping strike point mitigates the heat load. To avoid the negative effect of probe tip damage, a method based on sweeping strike point is used to get the normalized profile and study the decay length of particle and heat flux on the divertor target λ
js, λ
q. In the discharges with high radio-frequency (RF) heating power, electron temperature T
e is lower and λ
js is larger when the strike point locates on the horizontal target compared to the vertical target, probably due to the corner effect. In the Ohmic discharges, λ
js, λ
q are much larger compared to the discharges with high RF heating power, which may be attributed to lower edge T
e.
Simulation of crowd dynamics in pedestrian evacuation concerning panic contagion: A cellular automaton approach
Authors: Wang Guan-Ning , Chen Tao , Chen Jin-Wei , Deng Kaifeng , Wang Ru-Dong
Published: January 2022

The study of the panic evacuation process is of great significance to emergency management. Panic not only causes negative emotions such as irritability and anxiety, but also affects the pedestrians decision-making process, thereby inducing the abnormal crowd behavior. Prompted by the epidemiological SIR model, an extended floor field cellular automaton model was proposed to investigate the pedestrian dynamics under the threat of hazard resulting from the panic contagion. In the model, the conception of panic transmission status (PTS) was put forward to describe pedestrians’ behavior who could transmit panic emotions to others. The model also indicated the pedestrian movement was governed by the static and hazard threat floor field. Then rules that panic could influence decision-making process were set up based on the floor field theory. The simulation results show that the stronger the pedestrian panic, the more sensitive pedestrians are to hazards, and the less able to rationally find safe exits. However, when the crowd density is high, the panic contagion has a less impact on the evacuation process of pedestrians. It is also found that when the hazard position is closer to the exit, the panic will propagate for a longer time and have a greater impact on the evacuation. The results also suggest that as the extent of pedestrian’s familiarity with the environment increases, pedestrians spend less time to escape from the room and are less sensitive to the hazard. In addition, it is essential to point out that, compared with the impact of panic contagion, the pedestrian’s familiarity with environment has a more significant influence on the evacuation.
Topological phase transition in cavity optomechanical system with periodical modulation
Authors: Zhang Zhi-Xu , Qi Lu , Cui Wen-Xue , Zhang Shou , Wang Hong-Fu
Published: January 2022

We investigate the topological phase transition and the enhanced topological effect in a cavity optomechanical system with periodical modulation. By calculating the steady-state equations of the system, the steady-state conditions of cavity fields and the restricted conditions of effective optomechanical couplings are demonstrated. It is found that the cavity optomechanical system can be modulated to different topological Su–Schrieffer–Heeger (SSH) phases via designing the optomechanical couplings legitimately. Meanwhile, combining the effective optomechanical couplings and the probability distributions of gap states, we reveal the topological phase transition between trivial SSH phase and nontrivial SSH phase via adjusting the decay rates of cavity fields. Moreover, we find that the enhanced topological effect of gap states can be achieved by enlarging the size of system and adjusting the decay rates of cavity fields.
Analysis of identification methods of key nodes in transportation network
Authors: Lai Qiang , Zhang Hong-Hao
Published: January 2022

The identification of key nodes plays an important role in improving the robustness of the transportation network. For different types of transportation networks, the effect of the same identification method may be different. It is of practical significance to study the key nodes identification methods corresponding to various types of transportation networks. Based on the knowledge of complex networks, the metro networks and the bus networks are selected as the objects, and the key nodes are identified by the node degree identification method, the neighbor node degree identification method, the weighted k-shell degree neighborhood identification method (KSD), the degree k-shell identification method (DKS), and the degree k-shell neighborhood identification method (DKSN). Take the network efficiency and the largest connected subgraph as the effective indicators. The results show that the KSD identification method that comprehensively considers the elements has the best recognition effect and has certain practical significance.
Design and FPGA implementation of a memristor-based multi-scroll hyperchaotic system
Authors: Jia Sheng-Hao , Li Yu-Xia , Shi Qing-Yu , Huang Xia
Published: January 2022

A novel memristor-based multi-scroll hyperchaotic system is proposed. Based on a voltage-controlled memristor and a modulating sine nonlinear function, a novel method is proposed to generate the multi-scroll hyperchaotic attractors. Firstly, a multi-scroll chaotic system is constructed from a three-dimensional chaotic system by designing a modulating sine nonlinear function. Then, a voltage-controlled memristor is introduced into the above-designed multi-scroll chaotic system. Thus, a memristor-based multi-scroll hyperchaotic system is generated, and this hyperchaotic system can produce various coexisting hyperchaotic attractors with different topological structures. Moreover, different number of scrolls and different topological attractors can be obtained by varying the initial conditions of this system without changing the system parameters. The Lyapunov exponents, bifurcation diagrams and basins of attraction are given to analyze the dynamical characteristics of the multi-scroll hyperchaotic system. Besides, the field programmable gate array (FPGA) based digital implementation of the memristor-based multi-scroll hyperchaotic system is carried out. The experimental results of the FPGA-based digital circuit are displayed on the oscilloscope.
Filling up complex spectral regions through non-Hermitian disordered chains
Authors: Jiang Hui , Lee Ching Hua
Published: January 2022

Eigenspectra that fill regions in the complex plane have been intriguing to many, inspiring research from random matrix theory to esoteric semi-infinite bounded non-Hermitian lattices. In this work, we propose a simple and robust ansatz for constructing models whose eigenspectra fill up generic prescribed regions. Our approach utilizes specially designed non-Hermitian random couplings that allow the co-existence of eigenstates with a continuum of localization lengths, mathematically emulating the effects of semi-infinite boundaries. While some of these couplings are necessarily long-ranged, they are still far more local than what is possible with known random matrix ensembles. Our ansatz can be feasibly implemented in physical platforms such as classical and quantum circuits, and harbors very high tolerance to imperfections due to its stochastic nature.
Effect of void size and Mg contents on plastic deformation behaviors of Al–Mg alloy with pre-existing void: Molecular dynamics study
Authors: Wei Ning , Shi Ai-Qiang , Li Zhi-Hui , Ou Bing-Xian , Zhao Si-Han , Zhao Jun-Hua
Published: January 2022

The plastic deformation properties of cylindrical pre-void aluminum–magnesium (Al–Mg) alloy under uniaxial tension are explored using molecular dynamics simulations with embedded atom method (EAM) potential. The factors of Mg content, void size, and temperature are considered. The results show that the void fraction decreases with increasing Mg in the plastic deformation, and it is almost independent of Mg content when Mg is beyond 5%. Both Mg contents and stacking faults around the void affect the void growth. These phenomena are explained by the dislocation density of the sample and stacking faults distribution around the void. The variation trends of yield stress caused by void size are in good agreement with the Lubarda model. Moreover, temperature effects are explored, the yield stress and Young’s modulus obviously decrease with temperature. Our results may enrich and facilitate the understanding of the plastic mechanism of Al–Mg with defects or other alloys.
Characteristics of merging behavior in large crowds
Authors: Lian Liping , Mai Xu , Song Weiguo , Zhang Jun , Yuen Kwok Kit Richard , Lee Eric Wai Ming
Published: January 2022

Merging pedestrian flow can be observed often at public intersections and locations where two or more channels merge. Because of restrictions on the flow, pedestrian congestion, or even crowd disasters (e.g. Hajj crush 2015) happen easily at these junctions. However, studies on merging behaviors in large crowds remain rare. This paper investigates the merging characteristics of the pedestrian flow with controlled experiments under laboratory conditions. The formation of lanes is observed, and the lane separation width can vary for different density levels. Shannon entropy is used to analyze the utilization of the passage. The space usage in the merging area is most efficient when the width of the two branches is half that of the main corridor. Furthermore, the branch and main channel can mutually bottleneck each other in the large crowds and the flowrates for the upstream, downstream and branches are investigated. This study uses spatiotemporal diagrams to explore the clogging propagation of the merging flow as well as the relationship of the velocity and position. The results can be used as references for the design of public infrastructure and human safety management.
An investigation of PT -symmetry breaking in tight-binding chains
Authors: Luck Jean-Marc
Published: January 2022

We consider non-HermitianPT-symmetric tight-binding chains where gain/loss optical potentials of equal magnitudes ±iγare arbitrarily distributed over all sites. The main focus is on the thresholdγcbeyond whichPT-symmetry is broken. This threshold generically falls off as a power of the chain length, whose exponent depends on the configuration of optical potentials, ranging between 1 (for balanced periodic chains) and 2 (for unbalanced periodic chains, where each half of the chain experiences a non-zero mean potential). For random sequences of optical potentials with zero average and finite variance, the threshold is itself a random variable, whose mean value decays with exponent 3/2 and whose fluctuations have a universal distribution. The chains yielding the most robustPT-symmetric phase, i.e. the highest threshold at fixed chain length, are obtained by exact enumeration up to 48 sites. This optimal threshold exhibits an irregular dependence on the chain length, presumably decaying asymptotically with exponent 1, up to logarithmic corrections.
Large deviations for metastable states of Markov processes with absorbing states with applications to population models in stable or randomly switching environment
Authors: Monthus Cécile
Published: January 2022

The large deviations at level 2.5 are applied to Markov processes with absorbing states in order to obtain the explicit extinction rate of metastable quasi-stationary states in terms of their empirical time-averaged density and of their time-averaged empirical flows over a large time-window T. The standard spectral problem for the slowest relaxation mode can be recovered from the full optimization of the extinction rate over all these empirical observables and the equivalence can be understood via the Doob generator of the process conditioned to survive up to time T. The large deviation properties of any time-additive observable of the Markov trajectory before extinction can be derived from the level 2.5 via the decomposition of the time-additive observable in terms of the empirical density and the empirical flows. This general formalism is described for continuous-time Markov chains, with applications to population birth–death model in a stable or in a switching environment, and for diffusion processes in dimension d.
Timepix4, a large area pixel detector readout chip which can be tiled on 4 sides providing sub-200 ps timestamp binning
Authors: Llopart X. , Alozy J. , Ballabriga R. , Campbell M. , Casanova R. , Gromov V. , Heijne E.H.M. , Poikela T. , Santin E. , Sriskaran V. , Tlustos L. , Vitkovskiy A.
Published: January 2022

Timepix4 is a 24.7 × 30.0 mm2 hybrid pixel detector readout ASIC which has been designed to permit detector tiling on 4 sides. It consists of 448 × 512 pixels which can be bump bonded to a sensor with square pixels at a pitch of 55 µm. Like its predecessor, Timepix3, it can operate in data driven mode sending out information (Time of Arrival, ToA and Time over Threshold, ToT) only when a pixel has a hit above a pre-defined and programmable threshold. In this mode hits can be tagged to a time bin of <200 ps and Timepix4 can record hits correctly at incoming rates of ∼3.6 MHz/mm2/s. In photon counting (or frame-based) mode it can count incoming hits at rates of up to 5 GHz/mm2/s. In both modes data is output via between 2 and 16 serializers each running at a programmable data bandwidth of between 40 Mbps and 10 Gbps. The specifications, architecture and circuit implementation are described along with first electrical measurements and measurements with radioactive sources. In photon counting mode X-ray images have been taken at a threshold of 650 e− (with <10 masked pixels). In data driven mode images were taken of ToA/ToT data using a 90Sr source at a threshold of 800 e− (with ∼120 masked pixels).
Negative capacitance devices: sensitivity analyses of the developed TCAD ferroelectric model for HZO
Authors: Morozzi A. , Hoffmann M. , Mulargia R. , Slesazeck S. , Robutti E.
Published: January 2022

This work aims to investigate the suitability of innovative negative capacitance (NC) devices to be used in High Energy Physics experiments detection systems, featuring self-amplified, segmented, high granularity detectors. Within this framework, MFM (Metal-Ferroelectric-Metal) and MFIM (Metal-Ferroelectric-Insulator-Metal) structures have been investigated within the Technology-CAD environment. The strength of this approach is to exploit the behavior of a simple capacitor to accurately ad-hoc customize the TCAD library aiming at realistically modeling the polarization properties of devices fabricated with ferroelectric materials. The comparison between simulations and measurements in terms of polarization as a function of the applied electric field for both MFM and MFIM devices has been used for modeling and methodologies validation purposes. The analyses and results obtained for MFIM capacitors can be straightforwardly extended to the study of NC-FETs. This work would support the use of the TCAD modeling approach as a predictive tool to optimize the design and the operation of the new generation NC-FET devices for the future High Energy Physics experiments in the HL-LHC scenario. The NC working principle will be employed for particle detection applications in order to exceed the limits imposed by current CMOS technology in terms of power consumption, signal detectability and switching speed.
Optimization of detector placements in reduction of multiple counts for μSR measurements at China Spallation Neutron Source
Authors: Dong Jingyu , Pan Ziwen , Lin Zebin , Wang Zhe , He Zhengyang , Liu Jiandang , Zhang Hongjun , Jing Hantao , Bao Yu , Tang Jingyu , Ye Bangjiao
Published: January 2022

An Experimental Muon Source (EMuS) has been proposed to conduct muon spin rotation/relaxation/resonance (μSR) measurements at China Spallation Neutron Source (CSNS). To make better use of muons in each pulse, a highly segmented μSR spectrometer with more than 2000 detector channels is under design. Due to such high granularity of detectors, multiple counting events generated from particle scattering or spiral motion of positrons in a strong longitudinal field should be carefully considered in the design. According to the simulation, long scintillators have a good capability of angular discrimination. Detectors with cuboid geometries are better than those with frustum shapes. The cuboid detector with a length of 50 mm is longer enough to get the optimal range of discrimination angle. In a real μSR spectrometer, detectors can be placed parallelly along the beam direction or pointing to the sample. A figure of merit (FoM) has been proposed to compare such two arrangements by integrating their impacts on multiple counts and total counting loss in zero and longitudinal fields. The outstanding performance of multiple counting rejection due to the angular discrimination capability makes the pointing arrangement achieve much higher FoM. The simulation results can provide good support for the design of the highly segmented μSR spectrometer.
A deep-learning based raw waveform region-of-interest finder for the liquid argon time projection chamber
Authors: Acciarri R. , Baller B. , Basque V. , Bromberg C. , Cavanna F. , Edmunds D. , Fitzpatrick R.S. , Fleming B. , Green P. , James C. , Lepetic I. , Luo X. , Palamara O. , Scanavini G. , Soderberg M. , Spitz J. , Szelc A.M. , Uboldi L. , Wang M.H.L.S. , Wu W. , Yang T.
Published: January 2022

The liquid argon time projection chamber (LArTPC) detector
technology has an excellent capability to measure properties of
low-energy neutrinos produced by the sun and supernovae and to look
for exotic physics at very low energies. In order to achieve those
physics goals, it is crucial to identify and reconstruct signals in
the waveforms recorded on each TPC wire. In this paper, we report on
a novel algorithm based on a one-dimensional convolutional neural
network (CNN) to look for the region-of-interest (ROI) in raw
waveforms. We test this algorithm using data from the ArgoNeuT
experiment in conjunction with an improved noise mitigation
procedure and a more realistic data-driven noise model for simulated
events. This deep-learning ROI finder shows promising performance in
extracting small signals and gives an efficiency approximately twice
that of the traditional algorithm in the low energy region of
∼0.03–0.1 MeV. This method offers great potential to
explore low-energy physics using LArTPCs.
Inequality of household consumption and PM2.5 footprint across socioeconomic groups in China
Authors: Zhu Yuhan , Chen Guangwu , Xu Lixiao , Zhang Ying , Wang Yafei , Liang Sai
Published: January 2022

The United Nations Sustainable Development Goals have highlighted the challenge posed by increasing air pollution. This study allocates PM2.5 footprint to household consumption expenditure based on multi-regional input–output model and survey data collected from 30 000 households. The household indirect PM2.5 footprint related to spending on food, hospital, electricity, and education rank as the top four items, plus direct PM2.5 emissions, which in combination contribute more than 55% of total air pollution. Compared with the poor, the responsibilities for air pollution on the wealthy are more sensitive to changes in income, especially for high-end consumption categories, such as luxury goods and services, education and healthcare. Further, the wealthiest 20% of households cause 1.5 times the PM2.5 footprint per capita than exposure to PM2.5 emissions. The high-footprint household samples are concentrated in high-exposure areas. It is recommended that mitigation policies address inequality of PM2.5 footprint by targeting the top 20% of footprint groups with tags of wealthy, urban resident, well-educated, small family, and apartment living.
Classical string solutions in non-relativistic AdS5× S5: closed and twisted sectors
Authors: Fontanella Andrea , Nieto García Juan Miguel
Published: January 2022

We find classical closed string solutions to the non-relativistic AdS5× S5string theory which are the analogue of the BMN and GKP solutions for the relativistic theory. We show that non-relativistic AdS5× S5string theory admits aZ2orbifold symmetry which allows us to impose twisted boundary conditions. Among the solutions in the twisted sector, we find the one around which the semiclassical expansion in arXiv:2102.00008takes place.
The second Vassiliev measure of uniform random walks and polygons in confined space
Authors: Smith Philip , Panagiotou Eleni
Published: January 2022

Biopolymers, like chromatin, are often confined in small volumes. Confinement has a great effect on polymer conformations, including polymer entanglement. Polymer chains and other filamentous structures can be represented by polygonal curves in three-space. In this manuscript, we examine the topological complexity of polygonal chains in three-space and in confinement as a function of their length. We model polygonal chains by equilateral random walks in three-space and by uniform random walks (URWs) in confinement. For the topological characterization, we use the second Vassiliev measure. This is an integer topological invariant for polygons and a continuous functions over the real numbers, as a function of the chain coordinates for open polygonal chains. For URWs in confined space, we prove that the average value of the Vassiliev measure in the space of configurations increases as O(n
2) with the length of the walks or polygons. We verify this result numerically and our numerical results also show that the mean value of the second Vassiliev measure of equilateral random walks in three-space increases as O(n). These results reveal the rate at which knotting of open curves and not simply entanglement are affected by confinement.
Methodology of fire risk analysis in electrical installations of a production facility
Authors: Nikolsky O K , Shlionskaya Yu D , Gabova M A , Kachanov A N , Chernyshov V A
Published: January 2022

This article lists the principles of fire risk assessment and management of electrical installations, provides the main terms used in this subject area, and their meanings. The article also talks about factors affecting the magnitude of fire risk (risk-forming factors). Special attention is paid to the human factor. Formulas for probabilistic assessment of fire risks of electrical installations and an algorithm for assessing the fire hazard of electrical installations, as well as a scheme of the algorithm for calculating individual fire risk are given.
Methodology for comparing the energy efficiency of methods for regulating the performance of a blower station
Authors: Vecherkin Maksim , Sarvarov Anvar , Romanova Irina
Published: January 2022

A methodology for comparing the energy efficiency of different methods of regulating the total productivity of a blower station is presented. The basic principles of electrical modeling of duct networks are shown for the mathematical description of their properties and characteristics. The results of a comparison of the energy efficiency of regulating methods for a single fan and a group of five fans operating on a common line are presented. The conclusion about the high energy efficiency of the combination of start-stop control with smooth control using axial guide vanes for a blowing station of five fans is obtained.
Study of the thermal characteristics of the aluminum radiator ROYAL Thermo Evolution
Authors: Mar’ina Z G , Vereshchagin A Y , Novozhilova A V , Komarevtsev M A , Isaeva K O
Published: January 2022

The use of aluminum radiators in heating systems began with the foreign companies products such as Fondital Group, Global Radiatori, Ferroli, etc. There are now Russian aluminum radiators companies that adhere to European standards, for example ROYAL Thermo, Rifar. The thermal characteristics of radiators are usually specified by the manufacturer. However, they are not always confirmed in practice. This is due to the fact that radiator connecting method is not taken into account. In some technical data sheets, the power reduction factors are given depending on the difference between the average coolant temperature and the air temperature in the room. Therefore, the study of the influence of aluminium heating appliances connecting on its thermal characteristics is an actual task. The article presents the results of research of radiator of the ROYAL Thermo Evolution type, it was made on request from company specialising in heating systems design. It was found that the actual thermal power of one section varies in the range of 135 … 225 W, depending on the connection method of the radiator, the thermal power of the section declared by the manufacturer corresponds only to the diagonal «top-bottom» connection, the thermal power of the eight-section radiator with one-sided «top-bottom» connection is 12% higher than with a diagonal one. Studies show, when designing heating systems, it is necessary to take into account the connection method and the number of device sections.
Methodology for determining the flow rate and temperature of generated hot water when calculating the thermal diagram of a hot water boiler room
Authors: Gorshenin V P , Kachanov A N , Chernyshov VA , Korenkov D A , Maksimov V V
Published: January 2022

The consumption and temperature of hot water produced by boiler units are calculated using such a quantity as the consumption of the consumed network water. The formulas represent functional dependencies connecting the obtained values not only with the consumption of heating water, but also with the consumption of hot water supplied for recirculation, for own needs and for the needs of the fuel economy. They take into account the losses of network and hot water. The formulas are obtained as a result of the joint solution of the equation for the total consumption of hot water and the equation for its partial costs.
Modelling of Solar-Diesel Hybrid Power Plant
Authors: Vaskov A G , Mozder N Y , Narynbaev A F
Published: January 2022

The article highlights the problems of distributed energy generation and focuses on solar-diesel hybrid power plant modelling and optimization. Designing power systems based on renewable energy sources includes a very relevant task of building mathematical models of such systems and their elements. The article presents an approach and definition of mathematical models describing photovoltaic-diesel (PV-D) hybrid power system elements used in decision making processes as a part of PV-D operation control. An overview of PV module output power, performance and temperature models is given. Along with the analysis of the specific fuel consumption dependencies on the operating power of the diesel generator, an example of diesel power plant unit commitment is shown.
Method of calculation of water-diverting structures of low-head hydroelectric power plant for power supply of small power consumers
Authors: Zakharov Y Y , Lepeshkin A R
Published: January 2022

In recent years and in many countries the economic development of distant regions is increasingly dependent on energy resources. This fact makes the world scientific community pay more attention to the renewable energy sources. Special attention is paid to the solar, wind and small hydropower for electrical consumers who have no possibility to connect to the central power supply lines. In the countries that have water resources the financial support is given to the development of small and micro hydropower stations. The present work presents the results of the research on the improved method of calculation of water-diverting structures of low-head hydroelectric power plant with an installed cross-jet hydro turbine that is actual for the power supply of small power consumers. The presented method can be used for the preliminary analysis of morphometric characteristics of water course as well as the basic parameters of a cross-jet hydro turbine.
Ensuring effective transit of electrical energy using the laws of environmental cybernetics and the foundations of automatic control
Authors: Kachanov A N , Chernyshov V A , Burova A Yu , Belikov R P , Garifullin M Sh
Published: January 2022

The necessity of constant monitoring and maintenance of the environmental component in the organization of electric energy transit is substantiated. An original technique aimed at improving the efficiency of the functioning of the air electric network, based on the laws of environmental cybernetics and the basics of automatic control, is considered. The proposed scientific tools allow you to automatically monitor and control all processes that affect the efficiency of electric energy transit from the point of view of its environmental friendliness, and also allows you to form optimal regulatory influences aimed at stabilizing negative processes and disturbing factors arising inside the artificial electrobiological organism “Electric Line - Nature - Man”, which violate the stability of its ecological state.