bluuebunny/crossref_metadata_2025 huggingface dataset:
Control of the oscillation frequency of a vortex cluster in the trapped polariton condensate
Authors: Sitnik Kirill A. , Gnusov Ivan , Misko Mikhail , Töpfer Julian D. , Alyatkin Sergey , Lagoudakis Pavlos G.
Published: May 2024

An optically trapped exciton–polariton condensate forms states corresponding to excited energy levels of the confining potential. Recently, it was shown that non-uniformity of the ring-shaped trapping potential leads to the simultaneous occupation of two split energy levels. This results in the formation of an oscillating vortex cluster with periodically changing signs of topological charges. Here, we experimentally demonstrate the control of the topological charge oscillation frequency by tuning the ellipticity of the excitation profile. Our observations are corroborated using the linear Schrödinger equation for a two-dimensional quantum harmonic oscillator. Our findings open a promising avenue for the investigation of optical vorticity properties and their applications in controllable settings.
Chip-scale all-optical complex-valued matrix inverter
Authors: Liu Xinyu , Cheng Junwei , Zhou Hailong , Dong Jianji , Zhang Xinliang
Published: May 2024

Matrix inversion is a fundamental and widely utilized linear algebraic operation but computationally expensive in digital-clock-based platforms. Optical computing is a new computing paradigm with high speed and energy efficiency, and the computation can be realized through light propagation. However, there is a scarcity of experimentally implemented matrix inverters that exhibit both high integration density and the capability to perform complex-valued operations in existing optical systems. For the first time, we experimentally demonstrated an iterative all-optical chip-scale processor to perform the computation of complex-valued matrix inversion using the Richardson method. Our chip-scale processor achieves an iteration speed of 10 GHz, which can facilitate ultra-fast matrix inversion with the assistance of high-speed Mach–Zehnder interferometer modulators. The convergence can be attained within 20 iterations, yielding an accuracy of 90%. The proposed chip-scale all-optical complex-valued matrix inverter represents a distinctive innovation in the field of all-optical recursive systems, offering significant potential for solving computationally intensive mathematical problems.
Plasma evolution mechanism and distribution characteristics of supersonic vehicles
Authors: Wen Shuai , Fu Yuwei , Mi Kening , Liang Rong
Published: May 2024

During the flight of hypersonic vehicle, air will be decomposed and ionized due to the “friction” under ultra-high speed, thus forming a plasma layer. Because the plasma has the ability to absorb and reflect electromagnetic waves, the “black barrier” phenomenon is formed. In addition, when the hypersonic vehicle passes through the atmosphere, the surface temperature rises sharply due to aerodynamic heating, and the surface material undergoes a series of complex changes to form ablation. In this paper, the finite volume method and the laminar finite rate model are used to study the flow field velocity, pressure distribution, flow field temperature, and spatial distribution of each component of the aircraft at different Mach numbers, angles of attack, and heights. In the flow field of supersonic aircraft, N and O are mainly concentrated in the tail of the aircraft, NO is mainly concentrated in the head of the aircraft, and N2 and O2 are full of the whole space. Because of the accumulation of NO+ and O2+ in the tail of the aircraft, the charge accumulation is formed, which will further interfere with the electromagnetic wave signal. The mass fraction of N and O increases with the increase in Mach numbers, while the mass fraction of O2 decreases with the increase in Mach numbers. Different angles of attack will affect the asymmetry of the shock wave of the aircraft. In this paper, the evolution mechanism and distribution characteristics of aircraft plasma are revealed, which lay a theoretical foundation for solving the problem of black barrier and ablation.
Anomalous exchange bias behavior of NiFe/NiO bilayers induced by high-energy Xe+ ion irradiation
Authors: Zhang Yan , Li Bingsheng , Li Jun , Wang Yong , Ren Yong , Dai Bo
Published: May 2024

The alteration of the microstructure and magnetic performance of an exchange bias system, induced by ion irradiation, adversely affects the practical application of spintronic/storage devices in extreme environments. Here, we report systematically the correlation between static and dynamic magnetism and microstructure changes in NiFe/NiO exchange-biased bilayers after high-energy Xe+ ion irradiation. The effect of cascade collision induced by irradiation on exchange bias is studied through Monte Carlo simulations. It is distinguished from the traditional modification caused by keV-level ion irradiation. At low doses, the transition from amorphous to recrystallization occurs in the NiFe layer and the anomalous exchange bias behavior is induced. A step-like structure appears in the magnetic hysteresis loop and the step gradually shifts downward as the dose increases. At high doses, the exchange bias effect is suppressed due to the disordered antiferromagnetic moment caused by heat accumulation during cascade collision, which significantly decreases the thermal stability of the sample by 5–6 times. In addition, the non-monotonic evolution of high-frequency magnetic properties is observed with increasing irradiation doses. This work provides important foundational data for designing future spintronic/memory devices to enhance radiation tolerance and stability.
The surface temperatures of flat areas on the Moon
Authors: Zhang Dan , Zheng Wenchao
Published: May 2024

Lunar surface temperature (LST) is a quantity of special interest for interpreting the thermal character of the regolith. It is affected by the solar irradiance, earthshine, and heat flow for the flat areas on the Moon. We present an improved transient temperature model to calculate temperatures of lunar flat surfaces. The model consists of one-dimensional thermal diffusion equation and two boundary conditions. The improved lunar surface boundary condition allows one to precisely determine the effective solar irradiance (ESI) and earthshine. The simulated surface temperatures suggest consistency with the measured temperatures from the thermocouples of Apollo 15 and 17 heat flow experiments. From the LST simulated with the improved model, it is found the annual-seasonal variations present obvious latitude characters, with the highest surface temperature occurring in late October, November, and December separately at high (>∼72°) latitudes, middle latitudes, and low (<∼20°) latitudes, respectively; the lowest surface temperatures occur in late July. Furthermore, the discrepancies between the maximum and minimum temperatures decrease as latitude increases, as do the maximum and minimum lunar surface temperatures. The surface daytime temperature would change by 179.4 K with a 1322.5 W/m2 change in the ESI. A 0.12 W/m2 and 0.02 W/m2 change of the earthshine and heat flow would lead to 0.5 and 0.09 K in surface nighttime temperature, respectively.
Stable Ga2O3 soft x-ray detector with ultrahigh responsivity
Authors: Yu Shunjie , Liu Yan , Hou Xiaohu , Ding Mengfan , Zou Yanni , Guan Yong , Wu Zhao , Zhao Xiaolong , Hu Qin , Xu Guangwei , Long Shibing
Published: May 2024

Soft x-ray detectors play crucial roles in biology, chemistry, and lithography. Current soft x-ray detectors suffer from insufficient responsivity (R), excessively large cell area, and limited stability. Here, the β-Ga2O3 soft x-ray detector is constructed, and the effects of varying the sensitive layer thickness and voltage on the soft x-ray detection characteristics of the device are explored. Meanwhile, the mechanism of the multiplication ionization process from soft x-ray and the photoconductivity gain on the photoresponse performance of the device are analyzed. The device obtains the R up to 3.05 × 103 A/W under 300 eV soft x-ray irradiation at the synchrotron beamline, which is about 1.19 × 104 times higher than that of the conventional device. The Ga2O3 device also maintains stable operation under long-term irradiation and multicycle switching. These results indicate that Ga2O3 is an ideal candidate material for soft x-ray detection, which has great potential for applications such as imaging of biological cells.
Nature of point defects in monolayer MoS2 and the MoS2/Au(111) heterojunction
Authors: Anvari Roozbeh , Wang Wennie
Published: May 2024

Deposition of MoS2 on Au(111) alters the electronic properties of MoS2. In this study, we investigate the free-standing MoS2 monolayer and the MoS2/Au(111) heterostructure, with and without strain, as well as defects of interest in memristive and neuromorphic applications. We focus on the so-called atomristor devices based on monolayer materials that achieve resistive switching characteristics with the adsorption and desorption of metal adatoms. Our study confirms that the formation of midgap states is the primary mechanism behind the resistive switching. Our results show that strain lowers the adsorption/desorption energies of Au+defect structures of interest, leading to more favorable switching energies, but simultaneously reduces the switching ratio between states of differing conductivities. The presence of the Au(111) substrate additionally introduces non-uniform amounts of strain and charge transfer to the MoS2 monolayer. We propose that the induced strain contributes to the experimentally observed n- to p-type transition and Ohmic to Schottky transition in the MoS2 monolayer. The charge transfer leads to a permanent polarization at the interface, which can be tuned by strain. Our study has important implications on the role of the electrode as being a source of the observed variability in memristive devices and as an additional degree of freedom for tuning the switching characteristics of the memristor device.
High-performance CeFeCo/FeSiAl soft magnetic composites for megahertz power devices
Authors: Wan Wenchen , Wu Chen , Liu Guang , Chen Qiming , Yan Mi
Published: May 2024

Soft magnetic composites (SMCs) play a crucial role in modern electronics and electrical devices, for which challenges remain in maintaining magnetic performance and reducing loss at megahertz (MHz) frequencies. Here, CeFeCo/FeSiAl@ polyurethane (PU) SMCs have been rationally designed with the simultaneous achievement of large relative permeability, high domain-wall resonance frequency, and low power loss. As a rare-earth soft magnetic alloy, the CeFeCo is promising for high-frequency applications due to its easy-plane anisotropy, whereas FeSiAl is advantageous with increased electrical resistivity as well as approaching-zero magnetocrystalline anisotropy and magnetostriction. Hot pressing has been adopted to achieve a dense and homogeneous distribution of CeFeCo and FeSiAl powders in the PU for reduced magnetic dilution and eddy current loss. The resultant SMCs exhibit optional soft magnetic performance with large relative permeability of 21.0, low power loss of 3677.5 kW·m−3 at 5 MHz, and high domain-wall resonance frequency of 386.1 MHz. As such this work provides insights into the design of high-frequency SMCs incorporating novel rare-earth soft magnetic alloys.
Parametric analysis of the flow past a square cylinder in the interface of two different-velocity streams
Authors: ElMansy R. , Bergadà Josep M. , Sarwar Wasim , Mellibovsky Fernando
Published: May 2024

We address the linear stability of the two-dimensional incompressible flow past a square cylinder immersed in the wake of an upstream splitter plate, which separates two streams of different velocities, UT (top) and UB (bottom), to three-dimensional perturbations. The analysis is done in the so-called wake transition regime, across which two-dimensional vortex shedding incorporates spanwise modulation. In addition to the top and bottom stream Reynolds numbers (ReT,B=DUT,B/ν, with D the square cylinder side and ν the kinematic viscosity of the fluid), a parametric analysis is conducted to gauge the effects of splitter plate length (S) and the gap between the trailing edge of the splitter plate and the front face of the cylinder (G) on the leading three-dimensionalizing instabilities. Modes akin to the A- and B-type instabilities that characterize the wake transition regime past circular and square cylinders in homogeneous incoming flow are observed only at very small values of the top-to-bottom Reynolds number ratio R=ReT/ReB, while a third mode, mode C, is ubiquitous beyond more than very mild values of R. Increasing S at constant small G has a stabilizing effect on mode C, whose onset is pushed to higher values of R. Only for long S is mode A observed. Fixing a short S and increasing G results instead in a destabilization of mode C, and mode B is favored over mode A.
Computational fluid dynamics simulations of single-bubble evolution under synergy of ultrasound and an electrostatic field
Authors: Deng Jin-Jie , Yu Ming , Yang Ri-Fu
Published: May 2024

In the study reported here, a two-phase flow model was developed for the evolution of a single bubble under ultrasonic irradiation coupled with an electrostatic force. We started with the following assumptions: (I) the liquid is incompressible, (II) the effect of gravity is negligible in the liquid, (III) the bubble is insulating, and no free charges are distributed on the liquid–gas interface, and (IV) the liquid contains only one bubble. Using computational fluid dynamics, we analyzed how the bubble shape evolves under various conditions, and the main findings are as follows: (1) With increasing electric field strength, the bubble reaches a larger maximum area and a smaller minimum area. Furthermore, during the positive phase of ultrasound, a higher electric field strength leads to faster compression and a more slender bubble. (2) As the initial bubble radius is increased from 3 to 5 μm, the cavitation becomes significantly stronger, but when the initial bubble radius reaches 10 μm, the cavitation intensity decreases instead because of greater compression resistance caused by there being more gas in the bubble. (3) Cavitation cannot be triggered under an excessively low acoustic pressure amplitude, and an excessively high acoustic pressure amplitude results in weaker cavitation; the appropriate acoustic pressure amplitude is considered to be 1.35 atm.
Ab initio spectroscopy and thermochemistry of the platinum hydride ions, PtH+ and PtH−
Authors: Irikura Karl K.
Published: May 2024

Rovibrational levels of low-lying electronic states of the gas-phase, diatomic molecules, PtH+ and PtH−, are computed on potential-energy functions obtained by using a hybrid spin–orbit configuration-interaction procedure. PtH− has a well-separated Σ0++1 ground state, while the first two electronic states of PtH+ (Σ0++1 and 3Δ3) are nearly degenerate. Combining the experimental photoelectron (PE) spectra of PtH− with theoretical photodetachment spectroscopy leads to an improved value for the electron affinity of PtH, EA(PtH) = (1.617 ± 0.015) eV. When PtH− is a product of photodissociation of PtHCO2−, its PE spectrum is broad because of rotational excitation. Temperature-dependent thermodynamic functions and thermochemistry of dissociation are computed from the theoretical energy levels. Previously published energetic quantities for PtH+ and PtH− are revised. The ground 1Σ+ term of PtH+ is not well described using single-reference theory.
Highly sensitive and selective fluorescent “turn-on” sensor for Ag+ detection using MAPbBr3@PCN-221(Fe): An efficient Ag+-bridged energy transfer from perovskite to MOF
Authors: Li Songyuan , Zhao Gang , Sun Xinhang , Zheng Jiale , Liu Junhui , Huang Mingju
Published: May 2024

Metal ion-induced water pollution is attracting increasing public attention. Perovskite quantum dots and metal–organic frameworks (MOFs), owing to their outstanding properties, hold promise as ideal probes for detecting metal ions. In this study, a composite material, MAPbBr3@PCN-221(Fe), was prepared by encapsulating MAPbBr3 quantum dots with PCN-221(Fe), demonstrating high chemical stability and good reusability. The composite material shows a sensitive fluorescence turn-on signal in the presence of silver ions. The fluorescence intensity of the composite material exhibits a linear relationship with the concentration of Ag+ in the solution, with a low detection limit of 8.68 µM. Moreover, the fluorescence signal exhibits a strong selectivity for Ag+, enabling the detection of Ag+ concentration. This fluorescence turn-on signal originates from the Ag+-bridged energy transfer from the conductive band of MAPbBr3 to the excited state of the MOF, which is directly proportional to the concentration of silver ions. Simultaneously, this finding may open up a new possibility in artificial controlled energy transfer from perovskite to MOF for future development.
Extraction of flow features around a bridge pier with an evolving scour hole using Lagrangian coherent structures
Authors: Kalidindi Murali Krishnamraju , Khosa Rakesh , Bairwa Arvind Kumar
Published: May 2024

Local scouring around a bridge pier poses a severe threat to the safety of the bridge. A better understanding of flow features around the bridge piers is necessary for accurate prediction of the scour depth. The ridges of the finite-time Lyapunov exponent, called Lagrangian coherent structures (LCSs), were used to extract the flow features around a circular bridge pier with an evolving scour hole. The velocity field required for the LCSs computation was obtained using a three-dimensional Reynolds-averaged Navier–Stokes simulation. The simulation results were validated with the published experimental and numerical findings. The computed LCS stretching field extracted all the flow features around the bridge pier that were previously reported in the literature. In addition, the LCSs extracted the region of flow acceleration on both sides of the pier. The forward LCSs upstream of the pier extracted a particle trapping region, providing insight into the volume of fluid converting into the downflow. They extracted anchor-like structures inside the scour hole upstream of the pier. The analysis of velocity variations along the width and depth of the flow domain revealed that a change in the velocity profile is triggering the formation of LCS. The behavior of non-inertial particles released and integrated into the flow field revealed the significance of LCSs in particle transport. Using the LCS method, the study extracted the flow features that were difficult to extract with traditional flow visualization methods.
Rheological behavior of brain tissue: Experiments vs theory and forensic applications
Authors: Kosmerl Valentina , Bentil Sarah A. , Yarin Alexander L.
Published: May 2024

Experimental data describing the uniaxial compression and relaxation of brain tissue are compared to the predictions from a rheological model developed by Yarin and Kosmerl [“Rheology of brain tissue and hydrogels: A novel hyperelastic and viscoelastic model for forensic applications,” Phys. Fluids 35, 101910 (2023)]. A qualitative agreement between the model and experiments with swine brain tissue is confirmed, and the uniformly valid values (i.e., valid in all rheometric experiments without any change) of the rheological parameters are established. These are the values of the following four parameters: G (the shear modulus), κ (the bulk modulus), α (the dimensionless degree of hyperelasticity), and θ (the viscoelastic relaxation time). In addition, the present rheological model with the established rheological parameters is incorporated into a dynamic model of bullet penetration into brain tissue after a short-range shooting, when muzzle gases and/or air fill the bullet channel leading to its widening, wave propagation, fragmentation, and backspatter of brain tissue. This problem is of significant interest in forensic science because there is an urgent need to provide physics-informed models to reconstruct and analyze crime scenes.
Drag reducing performance and its influencing on natural yam mucilage
Authors: Shi Peng-fei , Hu Hai-bao , Wen Jun , Zhu Tao , Xie Luo
Published: May 2024

Yam mucilage is a novel environmentally friendly drag reducer. This study investigates drag reduction and degradation characteristics of Chinese yam mucilage, using an in-house rotor device. The effects of temperature, aging, and salts on the drag reduction rate (DR) of yam mucilage were also explored. Furthermore, the synergistic drag reduction properties of Chinese yam-polyethylene oxide (PEO) solution were investigated by blending Chinese yam mucilage with PEO. The rotational speed range of the rotor device was set at 200–700 r/min, corresponding to Reynolds numbers (Re) ranging from 30 396 to 106 385. The results demonstrated that the DR of yam mucilage initially increased, and then decreased at low concentrations, with increasing Re. Conversely, the DR of yam mucilage at high concentrations increased with increasing Re, albeit at a gradually slowing rate as concentration increased; however, the shear stability was gradually enhanced. Degradation testing revealed that yam slime exhibited semi-rigid, or rigid polymer characteristics, with notable shear stability. At a concentration of 2000 ppm and Re = 106 385, the maximum DR reached 44.1%. Prolonged heating and standing resulted in the reduced DR of yam mucilage. However, salt ions exerted dual effects on the DR of yam mucilage: Low concentrations of NaCl improved its effectiveness while Na2SO4 and high concentrations of NaCl diminished its efficacy. The addition of a small quantity of PEO was found to significantly enhance the drag reduction efficacy of yam mucilage, but no significant improvement in the shear stability of yam mucilage was observed. Yam mucilage exhibits promising potential as an environmentally friendly drag reducer with remarkable drag reduction capabilities.
The influence of bedding interface strength on the vertical propagation of hydraulic fractures
Authors: Xiong Dong , Ma Xinfang , Zhang Shicheng , He Jiayuan
Published: May 2024

Bedding interfaces in unconventional oil and gas may influence the vertical propagation path of hydraulic fractures. In this article, the cohesive elements were used to describe the tensile and shear damage of bedding interfaces. The vertical propagation law of hydraulic fractures under different stress, bedding interface tensile strength, and shear strength conditions was calculated. The simulation result revealed three types of hydraulic fractures: “H”-shaped, “fishbone”-shaped, and “I”-shaped fractures. The large vertical stress can cause difficulties in damaging bedding interfaces. When the vertical stress difference lies between 0 and 5 MPa, complex fishbone-shaped fractures can easily form. However, when the vertical stress exceeds 5 MPa, “I”-shaped fractures are more likely to occur. In case the vertical stress difference is less than 0 MPa, hydraulic fractures may encounter obstacles in crossing the bedding interface, resulting in the formation of “H”-shaped fractures. A larger tensile strength of the bedding interface will promote hydraulic fractures to pass through the bedding interface and make it easier to form “I”-shaped fractures, promoting the growth of fracture height, which promotes fracture height growth. On the other hand, a low shear strength in the bedding interface can cause shear slip, resulting in the formation of “H”-shaped fractures, which inhibits the growth of fracture height. Tensile shear mixed damage typically happens at the bedding interface. This type of damage can restrict the vertical propagation of hydraulic fractures, but it can also make the fractures more complicated.
Risk prediction for hydrogen sulfide emission based on sulfate-reducing bacteria in the water flooding oilfield
Authors: Sun Hongyu , Zhong Liguo , Zhu Yu , Zhu Jianjian , Zhou Yangyang
Published: May 2024

The water quality of the injection–production systems deteriorates as the water flooding oilfields are developed more deeply, and the content of sulfate-reducing bacteria (SRB) increases. Accordingly, hydrogen sulfide (H2S) emission related to SRB is intensified, which will arise safety and health problems. In order to investigate the effect of SRB on H2S emission in the water flooding oilfield, the contents of SRB and sulfide of the different nodes of a typical injection–production system of Daqing Oilfield were measured first, and then, H2S emission from water was simulated under different conditions. Consequently, a H2S emission prediction model was established based on Henry coefficient and the correlation between sulfide content and SRB content in the water. The measured sulfide contents were ranging from 0.25 to 6.34 mg/l, and the SRB contents were from 2.5 to 25 000 pcs/ml, and the highest SRB and sulfide contents were found in the settling tank. The correlation between sulfide content and SRB content was much remarkable, and the R2 value of the correlation analysis was 0.94. Henry coefficient of H2S emission was obtained from the simulated experiments under varied conditions such as sulfate content, oil content, and temperature. The established H2S emission prediction model was much reliable for predicting H2S emission for water flooding injection–production system, and the accuracy of the predicted H2S emission of four nodes of the injection–production system was larger than 95% compared to the measured results. This study provides theoretical guidance for predicting H2S emission risks in water flooding injection–production systems.
Experiences of occupational therapy students undertaking an Aboriginal and Torres Strait Islander health module: embedding cultural responsiveness in professional curricula
Authors: Mackenzie Lynette , Gwynn Josephine , Gilroy John
Published: May 2024

Objective Along with other Australian health professionals, occupational therapy students need to understand Aboriginal and Torres Strait Islander culture and health issues to develop their capacity to work effectively with this community and meet accreditation standards. The study aimed to explore the learning experiences of occupational therapy students during a module focused on Aboriginal and Torres Strait Islander peoples’ health issues and approaches. Methods A qualitative descriptive method was used. Individual interviews were audiotaped, transcribed and analysed thematically following the module. Participants were asked about their prior experience with Aboriginal and Torres Strait Islander peoples, feelings about undertaking the module, difficulties and highlights of the module, and how the module contributed to their learning. Results In all, 18 students participated in interviews. Interview themes were (1) student context of learning about Aboriginal and Torres Strait Islander peoples’ heath and culture, (2) experiencing the module with others and (3) student learning gains following the module. Conclusion Students developed in their self-awareness and understanding of Aboriginal and Torres Strait Islander peoples’ issues of relevance to occupational therapy. Further research is needed to evaluate educational activities with occupational therapy and other health professional students across Australia, and ongoing culturally responsiveness training for health professionals (post-registration).
Isn’t it time for health professionals to shift their focus from preaching politics to promoting peace?
Authors: Katz Naomi T. , Katz Merav L. , Adler Nikki R. , Green Jack
Published: May 2024

The magnitude of suffering on both the Israeli and Palestinian sides of the current war is beyond comprehension. Political agendas, misinformation and bias related to the conflict are being seen far too frequently in healthcare and medical academia. We believe it is time for healthcare professionals to redirect our attention away from politics and use our medical training to advocate for peace, care, and the welfare of all people, regardless of which side of the conflict they fall into. Politics in the workplace, particularly when disseminated information is divisive and, at times, based on opinion rather than fact, risks significant harm to patients, their families, and healthcare staff, as well as to institutional reputation. If we genuinely care for the well-being of patients and staff, we must lead by example and prevent healthcare systems and medical journals from being hijacked by politics.
Seabirds reveal mercury distribution across the North Atlantic
Authors: Albert Céline , Moe Børge , Strøm Hallvard , Grémillet David , Brault-Favrou Maud , Tarroux Arnaud , Descamps Sébastien , Bråthen Vegard Sandøy , Merkel Benjamin , Åström Jens , Amélineau Françoise , Angelier Frédéric , Anker-Nilssen Tycho , Chastel Olivier , Christensen-Dalsgaard Signe , Danielsen Johannis , Elliott Kyle , Erikstad Kjell Einar , Ezhov Alexey , Fauchald Per , Gabrielsen Geir W. , Gavrilo Maria , Hanssen Sveinn Are , Helgason Hálfdán H. , Johansen Malin Kjellstadli , Kolbeinsson Yann , Krasnov Yuri , Langset Magdalene , Lemaire Jérémy , Lorentsen Svein-Håkon , Olsen Bergur , Patterson Allison , Plumejeaud-Perreau Christine , Reiertsen Tone K. , Systad Geir Helge , Thompson Paul M. , Lindberg Thórarinsson Thorkell , Bustamante Paco , Fort Jérôme
Published: May 2024

Mercury (Hg) is a heterogeneously distributed toxicant affecting wildlife and human health. Yet, the spatial distribution of Hg remains poorly documented, especially in food webs, even though this knowledge is essential to assess large-scale risk of toxicity for the biota and human populations. Here, we used seabirds to assess, at an unprecedented population and geographic magnitude and high resolution, the spatial distribution of Hg in North Atlantic marine food webs. To this end, we combined tracking data of 837 seabirds from seven different species and 27 breeding colonies located across the North Atlantic and Atlantic Arctic together with Hg analyses in feathers representing individual seabird contamination based on their winter distribution. Our results highlight an east-west gradient in Hg concentrations with hot spots around southern Greenland and the east coast of Canada and a cold spot in the Barents and Kara Seas. We hypothesize that those gradients are influenced by eastern (Norwegian Atlantic Current and West Spitsbergen Current) and western (East Greenland Current) oceanic currents and melting of the Greenland Ice Sheet. By tracking spatial Hg contamination in marine ecosystems and through the identification of areas at risk of Hg toxicity, this study provides essential knowledge for international decisions about where the regulation of pollutants should be prioritized.
Real-time emulation of future global warming reveals realistic impacts on the phenological response and quality deterioration in rice
Authors: Itoh Hironori , Yamashita Hiroto , Wada Kaede C. , Yonemaru Jun-ichi
Published: May 2024

Decreased production of crops due to climate change has been predicted scientifically. While climate-resilient crops are necessary to ensure food security and support sustainable agriculture, predicting crop growth under future global warming is challenging. Therefore, we aimed to assess the impact of realistic global warming conditions on rice cultivation. We developed a crop evaluation platform, the agro-environment (AE) emulator, which generates diverse environments by implementing the complexity of natural environmental fluctuations in customized, fully artificial lighting growth chambers. We confirmed that the environmental responsiveness of rice obtained in the fluctuation of artificial environments is similar to those exhibited in natural environments by validating our AE emulator using publicly available meteorological data from multiple years at the same location and multiple locations in the same year. Based on the representative concentration pathway, real-time emulation of severe global warming unveiled dramatic advances in the rice life cycle, accompanied by a 35% decrease in grain yield and an 85% increase in quality deterioration, which is higher than the recently reported projections. The transcriptome dynamism showed that increasing temperature and CO
2
concentrations synergistically changed the expression of various genes and strengthened the induction of flowering, heat stress adaptation, and CO
2
response genes. The predicted severe global warming greatly alters rice environmental adaptability and negatively impacts rice production. Our findings offer innovative applications of artificial environments and insights for enhancing varietal potential and cultivation methods in the future.
PM
2.5
exposure contributes to anxiety and depression-like behaviors via phenyl-containing compounds interfering with dopamine receptor
Authors: Ji Shaoyang , Guo Yuqiong , Yan Wei , Wei Fang , Ding Jinjian , Hong Wenjun , Wu Xiaoyun , Ku Tingting , Yue Huifeng , Sang Nan
Published: May 2024

As a global problem, fine particulate matter (PM
2.5
) really needs local fixes. Considering the increasing epidemiological relevance to anxiety and depression but inconsistent toxicological results, the most important question is to clarify whether and how PM
2.5
causally contributes to these mental disorders and which components are the most dangerous for crucial mitigation in a particular place. In the present study, we chronically subjected male mice to a real-world PM
2.5
exposure system throughout the winter heating period in a coal combustion area and revealed that PM
2.5
caused anxiety and depression-like behaviors in adults such as restricted activity, diminished exploratory interest, enhanced repetitive stereotypy, and elevated acquired immobility, through behavioral tests including open field, elevated plus maze, marble-burying, and forced swimming tests. Importantly, we found that dopamine signaling was perturbed using mRNA transcriptional profile and bioinformatics analysis, with Drd1 as a potential target. Subsequently, we developed the
Drd1
expression-directed multifraction isolating and nontarget identifying framework and identified a total of 209 compounds in PM
2.5
organic extracts capable of reducing
Drd1
expression. Furthermore, by applying hierarchical characteristic fragment analysis and molecular docking and dynamics simulation, we clarified that phenyl-containing compounds competitively bound to DRD1 and interfered with dopamine signaling, thereby contributing to mental disorders. Taken together, this work provides experimental evidence for researchers and clinicians to identify hazardous factors in PM
2.5
and prevent adverse health outcomes and for local governments and municipalities to control source emissions for diminishing specific disease burdens.
Mimicking natural deterrent strategies in plants using adhesive spheres
Authors: van Zwieten Ralph , Bierman Thijs V. , Klinkhamer Peter G. L. , Bezemer T. Martijn , Vrieling Klaas , Kodger Thomas E.
Published: May 2024

With a continuous increase in world population and food production, chemical pesticide use is growing accordingly, yet unsustainably. As chemical pesticides are harmful to the environment and developmental resistance in pests is increasing, a sustainable and effective pesticide alternative is needed. Inspired by nature, we mimic one defense strategy of plants, glandular trichomes, to shift away from using chemical pesticides by moving toward a physical immobilization strategy via adhesive particles. Through controlled oxidation of a biobased starting material, triglyceride oils, an adhesive material is created while monitoring the reactive intermediates. After being milled into particles, nanoindentation shows these particles to be adhesive even at low contact forces. A suspension of particles is then sprayed and found to be effective at immobilizing a target pest, thrips,
Frankliniella occidentalis
. Small arthropod pests, like thrips, can cause crop damage through virus transfer, which is prevented by their immobilization. We show that through a scalable fabrication process, biosourced materials can be used to create an effective, sustainable physical pesticide.
Premeiotic 24-nt phasiRNAs are present in the
Zea
genus and unique in biogenesis mechanism and molecular function
Authors: Zhan Junpeng , Bélanger Sébastien , Lewis Scott , Teng Chong , McGregor Madison , Beric Aleksandra , Schon Michael A. , Nodine Michael D. , Meyers Blake C.
Published: May 2024

Reproductive phasiRNAs (phased, small interfering RNAs) are broadly present in angiosperms and play crucial roles in sustaining male fertility. While the premeiotic 21-nt (nucleotides) phasiRNAs and meiotic 24-nt phasiRNA pathways have been extensively studied in maize (
Zea mays
) and rice (
Oryza sativa
), a third putative category of reproductive phasiRNAs–named premeiotic 24-nt phasiRNAs–have recently been reported in barley (
Hordeum vulgare
) and wheat (
Triticum aestivum
). To determine whether premeiotic 24-nt phasiRNAs are also present in maize and related species and begin to characterize their biogenesis and function, we performed a comparative transcriptome and degradome analysis of premeiotic and meiotic anthers from five maize inbred lines and three teosinte species/subspecies. Our data indicate that a substantial subset of the 24-nt phasiRNA loci in maize and teosinte are already highly expressed at the premeiotic phase. The premeiotic 24-nt phasiRNAs are similar to meiotic 24-nt phasiRNAs in genomic origin and dependence on DCL5 (Dicer-like 5) for biogenesis, however, premeiotic 24-nt phasiRNAs are unique in that they are likely i) not triggered by microRNAs, ii) not loaded by AGO18 proteins, and iii) not capable of mediating
PHAS
precursor cleavage. In addition, we also observed a group of premeiotic 24-nt phasiRNAs in rice using previously published data. Together, our results indicate that the premeiotic 24-nt phasiRNAs constitute a unique class of reproductive phasiRNAs and are present more broadly in the grass family (Poaceae) than previously known.
Translating artworks
Authors: Bartolini Chiara
Published: May 2024

This contribution, which sits at the intersection of translation studies and museum studies (MS), seeks to explore multiple forms of interpretation developed by museums, whereby interpretation is considered, from an MS perspective, as a variety of museum aids creating a context and conveying mediated meanings about the objects on display. The focus is on individual interpretative texts produced by an Italian art gallery, the Pinacoteca di Brera, as the results of various interpretation processes about the same piece of art: the traditional label, the online description, the general audio guide, and the audio description for the blind and the visually impaired (the latter comprising both the visual description itself and the art historical description). A selection of texts in Italian and their translations into English describing four artworks from the museum collection are compared in a bid to shed light on the distinct layers of interpretation and ways of translating and representing the objects for different expected audiences through intralingual, interlingual, and intersemiotic translation practices.
Research on Quantitative Expression of Priority for Imaging Satellite Requirements
Authors: Zhao Yulong , Zhang Yuan , Xu Can , Hou Xiang
Published: May 2024

This article conducts a quantitative expression study on the priority of imaging satellite requirements to address the issue of quickly and scientifically sorting user imaging requirements. Firstly, a priority evaluation system for imaging requirements was constructed by comprehensively considering factors such as user level, importance of requirements, observation efficiency, and urgency. Secondly, quantitative indicators were provided for the relative importance of various elements that affect the priority of satellite requirement through expert scoring, and a judgment matrix for the priority evaluation system was established. Finally, the weight coefficient vector of the evaluation system was solved using the principle of minimum square difference. A quantitative expression for imaging satellite requirement priority was constructed based on the weighted sum method. The effectiveness of the quantitative expression for imaging satellite requirement priority was verified through experimental data, effectively solving the problem of imaging requirement selection when satellite resources are insufficient.
A Unified SoS and System Architecture Modeling Approach Based on Language Transformation and Extension Mechanisms
Authors: Guo Yuqiang , Li Yingxu , Zhao Jun , Zhao Hui , Guo Junxian
Published: May 2024

UAFML or UPDM is the language for modeling System of System(SoS) architecture. While SysML is used to model system architecture with solid connections with requirements, multidisciplinary analysis, software development, verification, etc. Many companies export the SoS architecture model into an XMI file or even a Word document to the system-architecture-level design team to perform further development. It will cost more time and may cause information inconsistency in practice. To bridge the gap, studying a more economical way to perform the modeling information exchange is necessary. This paper studied architecture modeling language building and transformation mechanisms and proposed a unified SoSE and SE modeling approach, which will make the most of the architecture model, guarantee the different architecture level model consistency and save cost.
Study on the Control Mechanism of DBD-PA on Near Wall Flow
Authors: Zhang Yanghui , Qian Qiaochu , Hu Xingjun
Published: May 2024

Based on the Shyy plasma simulation model, this paper studied the control mechanism of positive and reverse DBD-PA (dielectric barrier discharge plasma actuator) on near wall flow, and discussed the influence of incoming boundary layer thickness and parallel double DBD-PA on control effect. The results showed that: the positive DBD-PA had an obvious acceleration effect on the near wall flow field, and the acceleration effect first increased and then decreased; the reverse DBD-PA had an obvious deceleration effect on the near wall flow field, and the deceleration effect decreased gradually; increasing the thickness of the incoming boundary layer can improve the control effect, but the improvement effect is gradually reduced; when parallel double DBD-PA, the control effect of positive and reverse DBD-PA is improved by 88.7 % and 62.5 % respectively.
Comparative Study of In-Wheel Motor Control Systems Based on Multiple Controllers
Authors: Pan Deng , Liu Yicai , Gao Jun
Published: May 2024

This paper proposes a comparative study of hub motor control based on multiple control strategies (pi control, direct torque control, model predictive current control) to address the problem of slow dynamic response in traditional vector control of electric vehicle permanent magnet synchronous hub motors. By strictly extracting the mathematical model of the motor, the desired target voltage vector and current vector are derived using three controllers and applied to the controlled object. Finally, experiments are conducted on a simulation platform, and the experimental conclusions are used to compare and analyze the reliability and adaptability of different controllers.
Numerical Study on Cable Force Adjustment System for Replacing Slings of In-Service Suspension Bridges
Authors: Mao Yan , Han Xu , Zhang Xinmin , Li Pengfei , Wei Sicong
Published: May 2024

To conduct a systematic investigation on the replacement scheme for slings in service of suspension bridges, five feasible tensioning schemes were determined based on numerical simulation and analytical methods using the sling replacement project of an existing bridge as a case study. The safety performance of the bridge was evaluated by considering parameters such as sling position, quantity, order, and force value. According to the coupling relationship between different slings during the tensioning process, a precise analytical calculation model for adjusting cable force of the suspender is determined. The findings demonstrate that the dynamic performance of the completed bridge solely depends on its final state and remains unaffected by the intermediate tensioning process of suspension. The research findings suggest that symmetrically batch or stepwise tensioning can be applied to the suspension bridge slings with cable adjustment sequence from both ends to middle span replacement scheme to minimize structural response and optimize mechanical properties.
Research on the Overall Influence of Magnus Cylinders on Airfoil Structures and Structural Optimization
Authors: Su Zhengyu , Yang Baosheng , Li Yongyuan , Jiang Yi , Ren Fantao
Published: May 2024

With the coupling effect of Magnus cylinder and symmetric airfoil as the research object, the numerical analysis method is used to study the influence of Magnus cylinder layout position and protruding height ratio on the aerodynamic characteristics of the airfoil. Based on the aerodynamic law of Magnus airfoil and Optistruct deformer optimisation method, the optimisation model of Magnus airfoil structure is proposed. Results reveal that the placement of the Magnus cylinder near the leading edge of the upper surface and the trailing edge of the lower surface significantly impacts the aerodynamic characteristics of the Magnus airfoil. Moreover, as the protruding height ratio increases, the aerodynamic performance of the airfoil experiences an initial enhancement followed by a reduction. Under the conditions of an 8° angle of attack and a Reynolds number of 9.5×105, the optimized aerodynamic performance of the Magnus airfoil demonstrates a remarkable increase of 17.5% compared to the baseline airfoil, accompanied by a significant reduction of 28.1% in stress concentration.
PromptNet: Prompt Learning for Roof Photovoltaic Potential Assessment
Authors: Han Xu , Wang Jing , Liu Xun , Du Jun , Bai Xiaolan , Ji Ran
Published: May 2024

An increasing number of works have been proposed to use remote sensing images to assess the potential for rooftop Photovoltaic (PV) energy development in buildings. However, most methods focus mainly on the remote sensing images themselves, ignoring the key prior information of building type. Thus most works with Deeplabv3+ as backbone present suboptimal performance. To overcome this challenge, we propose a novel approach PromptNet that embeds the building types as prior knowledge and feed it into prompt learning for predict roof PV energy Potential. Specifically, a pre-trained semantic segmentation network, Deeplabv3+, is first constructed to detect potential building rooftops from remote sensing images. Then, the buildings are categorized into five types based on their functions, including government buildings, public buildings, industrial and commercial factories, agricultural housing, and other building types. Finally, by using prompt learning, the prior knowledge of buildings is established and associated with the rooftops that are suitable for PV energy development. This is embedded into a deep learning network, filtering out unsuitable rooftops, and significantly improving the accuracy of rooftop PV energy development. Comprehensive experiments show that the proposed method achieves 81.18% accuracy and 76.90% IOU in predicting the potential for rooftop PV energy, a 10.97% improvement in IoU compared to the backbone without prior knowledge.