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Landau quantization effects on damping Kawahara solitons in electron–positron–ion plasma in rotating ionized medium

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Communications in Theoretical Physics 2024年第10期76卷 143-152页

作者： E i El-Awady S Hussain N Akhtar Department of Physics Faculty of Science Port Said University Theoretical Physics Division (TPD) PINSTECH

For the dynamics of three-dimensional electron–positron–ion plasmas, a fluid quantum hydrodynamic model is proposed by considering Landau quantization effects in dense ***–neutral collisions in the presence of the Coriolis force are also considered. The application of the reductive perturbation technique produces a wave evolution equation represented by a damped Korteweg–de Vries equation. This equation, however, is insufficient for describing waves in our system at very low dispersion coefficients. As a result, we considered the highest-order perturbation, which resulted in the damped Kawahara equation. The effects of the magnetic field, Landau quantization, the ratio of positron density to electron density, the ratio of positron density to ion density, and the direction cosine on linear dispersion laws as well as soliton and conoidal solutions of the damped Kawahara equation are explored. The understanding from this research can contribute to the broader field of astrophysics and aid in the interpretation of observational data from white dwarfs.

关键词： Coriolis force Kawahara equation Landau quantization magnetoplasmas quantum plasma solitary and cnoidal waves

Developing a two-decadal time-record of rice field maps using Landsat-derived multi-index image collections with a random forest classifier:A Google Earth Engine based approach

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information Processing in Agriculture 2024年第2期11卷 260-275页

作者： W.Ashane M.Fernando i.P.Senanayake Department of Nano Science Technology Wayamba University of Sri LankaKuliyapitiya 60200Sri Lanka Dchoolf Engineing CllegeoEngineeringSience and EnionmentThe UniversyewcastleCallaghanW2Austraia

Historic maps showing the temporal distribution of rice fields are important for precision agriculture,irrigation optimisation,forecasting crop yields,land use management and formulating ***,mapping rice felds using traditional ground surveys is impractical when high cost,time and labour requirements are considered,and the availability of such detailed records is *** satellite remote sensing appears to be a viable solution,conventional segmentation and classification methods with spectral bands are often unable to contrast the distinct characteristics between rice fields and other vegetation *** this end,we explored a novel,Google Earth Engine(GEE)based multiindex random forest(RF)classification approach to map rice fields over two *** images from 2000 to 2020 of two Sri Lankan rice cultivation districts were extracted from GEE and a multi-index RF classification algorithm was applied to distinguish the rice *** results showed above 80%accuracy for both training and validation,when compared against high spatial resolution Google Earth *** essence,multi-index sampling and RF together synergised the compelling classifcation accuracy by effectively capturing vegetation,water(ponding)and soil characteristics unique to the rice felds using a single-click *** maps developed in this study were further compared against the MODiS land cover type product(MCD12Q1)and the corresponding superior statistics on rice fields demonstrated the robustness of the proposed *** work seeking effective index combinations is recommended,and this approach can potentially be extended to other crop analyses elsewhere.

关键词： Google Earth Engine(GEE) image classification Random forest Mapping rice fields Time series analysis Vegetation index

Rice Husk at a Glance:From Agro-industrial to Modern Applications

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Rice science 2024年第1期31卷 14-32页

作者： Masoumeh KORDi Naser FARROKHi Martin i.PECH-CANUL Asadollah AHMADiKHAH Department of Cell&Molecular Biology Faculty of Life Sciences and BiotechnologyShahid Beheshti UniversityTehran ***Iran 1062 Metallurgical industry Avenue Industrial Park Saltillo-Ramos ArizpeRamos ArizpeCoahuila 25900Mexico

Excessive waste production has led to the concept of a circular bioeconomy to deliver valuable by-products and improve environmental *** annual worldwide rice production accounts for more than 750 million tons of grain and 150 million tons of *** husk(RH)contains valuable biomaterials with extensive applications in various *** proportions of each component depend primarily on rice genotype,soil chemistry,and climatic *** and its derivatives,including ash,biochar,hydrochar,and activated carbon have been placed foreground of applications in agriculture and other *** the investigation on RH’s compositions,microstructures,and by-products has been done copiously,owing to its unique features,it is still an open-ended area with enormous scope for innovation,research,and ***,we reviewed the latest applications of RH and its derivatives,including fuel and other energy resources,construction materials,pharmacy,medicine,and nanobiotechnology to keep this versatile biomaterial in the spotlight.

关键词： circular bioeconomy rice husk activated carbon rice husk ash rice husk biochar rice husk hydrochar rice husk application

A Statistical Study of Magnetic Flux Emergence in Solar Active Regions Prior to Strongest Flares

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Research in Astronomy and Astrophysics 2024年第4期24卷 147-160页

作者： Alexander S.Kutsenko Valentina i.Abramenko Andrei A.Plotnikov Crimean Astrophysical Observatory p/o NauchnyCrimea298409Russia

Using the data on magnetic field maps and continuum intensity for Solar Cycles 23 and 24,we explored 100 active regions(ARs)that produced M5.0 or stronger *** focus on the presence/absence of the emergence of magnetic flux in these ARs 2-3 days before the strong flare *** found that 29 ARs in the sample emerged monotonically amidst quiet-Sun.A major emergence of a new magnetic flux within a pre-existing AR yielding the formation of a complex flare-productive configuration was observed in another 24 *** 30 ARs,an insignificant(in terms of the total magnetic flux of pre-existing AR)emergence of a new magnetic flux within the pre-existing magnetic configuration was observed;for some of them the emergence resulted in a formation of a configuration with a small δ-sunspot;11 out of 100 ARs exhibited no signatures of magnetic flux emergence during the entire interval of *** six cases the emergence was in progress when the AR appeared on the Eastern limb,so that the classification and timing of emergence were not *** conclude that the recent flux emergence is not a necessary and/or sufficient condition for strong flaring of an *** flux emergence rate of flare-productive ARs analyzed here was compared with that of flare-quiet ARs analyzed in our previous *** revealed that the flare-productive ARs tend to display faster emergence than the flare-quiet ones do.

关键词： Sun:activity Sun:flares Sun:magnetic fields

Radiative loss of coherence in free electrons:a long-range quantum phenomenon

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Light(Science & Applications) 2024年第2期13卷 294-301页

作者： Cruz i.Velasco Valerio Di Giulio F.Javier García de Abajo iCFO-institut de Ciencies Fotoniques The Barcelona Institute of Science and Technology08860Castelldefels(Barcelona)Spain iCREA-institucióCatalana de Recerca i Estudis Avançats Passeig Lluís Companys 2308010BarcelonaSpain

Quantum physics rules the dynamics of small objects as they interact over microscopic length ***,quantum correlations involving macroscopic distances can be observed between entangled photons as well as in atomic gases and matter waves at low *** long-range nature of the electromagnetic coupling between charged particles and extended objects could also trigger quantum phenomena over large ***,we reveal a manifestation of quantum mechanics that involves macroscopic distances and results in a nearly complete depletion of coherence associated with which-way free-electron interference produced by electron-radiation coupling in the presence of distant extended *** is a ubiquitous effect that we illustrate through a rigorous theoretical analysis of a two-path electron beam interacting with a semi-infinite metallic plate and find the inter-path coherence to vanish proportionally to the path separation at zero temperature and exponentially at finite *** investigated regime of large distances originates in the coupling of the electron to radiative modes assisted by diffraction at material structures but without any involvement of material *** the fundamental interest of this macroscopic quantum phenomenon,our results suggest an approach to measuring the vacuum temperature and nondestructively sensing the presence of distant objects.

关键词： temperature quantum macroscopic

Particle Size Optimization of Thermochemical Salt Hydrates for High Energy Density Thermal Storage

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Energy & Environmental Materials 2024年第2期7卷 326-333页

作者： Andrew Martin Drew Lilley Raνi Prasher Sumanjeet Kaur Energy Technologies Area Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA Department of Mechanical Engineering UC BerkeleyBerkeleyCA 94720USA

Thermal energy storage(TES)solutions offer opportunities to reduce energy consumption,greenhouse gas emissions,and ***,they can help reduce the peak load and address the intermittency of renewable energy sources by time shifting the load,which are critical toward zero energy *** materials(TCMs)as a class of TES undergo a solid-gas reversible chemical reaction with water vapor to store and release energy with high storage capacities(600 kWh m^(-3))and negligible self-discharge that makes them uniquely suited as compact,stand-alone units for daily or seasonal ***,TCMs suffer from instabilities at the material(salt particles)and reactor level(packed beds of salt),resulting in poor multi-cycle efficiency and high-levelized cost of *** this study,a model is developed to predict the pulverization limit or Rcrit of various salt hydrates during thermal *** is critical as it provides design rules to make mechanically stable TCM composites as well as enables the use of more energy-efficient manufacturing process(solid-state mixing)to make the *** model is experimentally validated on multiple TCM salt hydrates with different water content,and effect of Rcrit on hydration and dehydration kinetics is also investigated.

关键词： high energy density hydration kinetics long-term cycling thermal energy storage thermochemical materials

ionogels and eutectogels for stable and long-term EEG and EMG signal acquisition

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Materials Futures 2024年第3期3卷 95-110页

作者： Asmita Veronica Hnin Yin Yin Nyein i-Ming Hsing Department of Chemical and Biological Engineering The Hong Kong University of Science and TechnologyClear Water BayHong Kong Special Administrative Region of ChinaPeople’s Republic of China

Neurological injuries and disorders have a significant impact on individuals’quality of life,often resulting in motor and sensory *** assess motor performance and monitor neurological disorders,non-invasive techniques such as electroencephalography(EEG)and electromyography(EMG)are commonly *** employed wet electrodes with conductive gels are limited by lengthy skin preparation time and allergic *** dry electrodes and hydrogel-based electrodes can mitigate these issues,their applicability for long-term monitoring is *** electrodes are susceptible to motion artifacts,whereas hydrogel-based electrodes face challenges related to water-induced ***,ionogels and eutectogels derived from ionic liquids and deep eutectic solvents have gained immense popularity due to their non-volatility,ionic conductivity,thermal stability,and ***,in particular,exhibit superior *** characteristics make them suitable alternatives for the development of safer,robust,and reliable EEG and EMG ***,research specifically focused on their application for EEG and EMG signal acquisition remains *** article explores the electrode requirements and material advancements in EEG and EMG sensing,with a focus on highlighting the benefits that ionogels and eutectogels offer over conventional *** sheds light on the current limitations of these materials and proposes areas for further improvement in this *** potential of these gel-based materials to achieve a seamless interface for high-quality and long-term electrophysiological signal acquisition is *** the unique properties of ionogels and eutectogels holds promise for future advancements in EEG and EMG electrode materials,leading to improved monitoring systems and enhanced patient outcomes.

关键词： ionogel eutectogel electrode electroencephalography electromyography

Data-driven modeling on anisotropic mechanical behavior of brain tissue with internal pressure

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Defence Technology（防务技术） 2024年第3期33卷 55-65页

作者： Zhiyuan Tang Yu Wang Khalil i.Elkhodary Zefeng Yu Shan Tang Dan Peng State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDalian University of Technology116023DalianPR China The Department of Mechanical Engineering The American University in CairoNew Cairo11835Egypt Department of Neurology The Second Hospital of Dalian Medical UniversityDalian116023PR China

Brain tissue is one of the softest parts of the human body,composed of white matter and grey *** mechanical behavior of the brain tissue plays an essential role in regulating brain morphology and brain ***,traumatic brain injury(TBi)and various brain diseases are also greatly influenced by the brain's mechanical *** white matter or grey matter,brain tissue contains multiscale structures composed of neurons,glial cells,fibers,blood vessels,etc.,each with different mechanical *** such,brain tissue exhibits complex mechanical behavior,usually with strong nonlinearity,heterogeneity,and directional *** a constitutive law for multiscale brain tissue using traditional function-based approaches can be very ***,this paper proposes a data-driven approach to establish the desired mechanical model of brain *** focus on blood vessels with internal pressure embedded in a white or grey matter matrix material to demonstrate our *** matrix is described by an isotropic or anisotropic nonlinear elastic model.A representative unit cell(RUC)with blood vessels is built,which is used to generate the stress-strain data under different internal blood pressure and various proportional displacement loading *** generated stress-strain data is then used to train a mechanical law using artificial neural networks to predict the macroscopic mechanical response of brain tissue under different internal ***,the trained material model is implemented into finite element software to predict the mechanical behavior of a whole brain under intracranial pressure and distributed body *** with a direct numerical simulation that employs a reference material model,our proposed approach greatly reduces the computational cost and improves modeling *** predictions made by our trained model demonstrate sufficient ***,we find that the level of internal blood pressur

关键词： Data driven Constitutive law Anisotropy Brain tissue internal pressure

Ferritin and mortality in hemodialysis patients with COViD-19:A systematic review and meta-analysis

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Asian Pacific Journal of Tropical Medicine 2024年第1期17卷 4-11页

作者： Ni Wayan Anantika Riani i Gde Raka Widiana Yenny Kandarini Nephrology Division Department of Internal MedicineUdayana University/Udayana University HospitalBaliIndonesia Nephrology Division Department of Internal MedicineUdayana University/Prof.Dr.I.G.N.G.Ngoerah General HospitalBaliIndonesia

Objective:To investigate the difference in serum ferritin levels between deceased and surviving regular hemodialysis patients with ***:We conducted a systematic search across four databases following the PRiSMA statement *** reporting ferritin levels and mortality of regular hemodialysis patients with COViD-19 were *** the random-effects model,we performed a meta-analysis to determine the mean difference in serum ferritin levels between the studied groups,along with their corresponding 95%confidence *** meta-analysis was carried out using Review Manager 5.4 and Stata ***:A total of 1013 patients from seven studies were included in this *** meta-analysis showed higher mean serum ferritin in the deceased compared to surviving regular hemodialysis patients with COViD-19,with a mean difference of 449.43 ng/mL[95%Ci(244.07,654.80),Pi2=58%,P=0.003].Conclusions:Our study found a higher mean of serum ferritin levels in the deceased compared to surviving regular hemodialysis patients with COViD-19.

关键词： Ferritin Mortality Hemodialysis COViD-19 inflammation