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We experimentally investigate phase shift gained by electromagnetic radiation transmitted through a two-dimensional electron system (2DES) on a dielectric substrate. We systematically examined the dependence of the phase shift on the radiation frequency and 2DES electron density for the GaAs semiconductor substrate. A theoretical approach was developed that found good agreement with experimental results. We demonstrate a practically achievable phase shift of 105 °. Obtained findings pave the way for the design of terahertz devices that can manipulate the radiation phase in a controlled and precise manner. [ABSTRACT FROM AUTHOR]

Optical metasurfaces can be used to realize various peculiar optical effects, and their mechanisms of the controlling optical phase can be roughly categorized into three types: resonant phase, geometric phase, and propagation phase, also known as the dynamic phase. Multiple mechanisms can be employed to manipulate the phase and amplitude of one metasurface. Therefore, discovering more profound and diverse methods can provide additional degrees of application freedom. This paper proposes a control principle based on electric multipole expansion. We found that for a unit structure formed by dual-metal bars on a metasurface, the radiation of its dipole is equivalent to the interference results of the dual-metal bars. Moreover, the radiation of the quadrupole enables independent control for amplitude and phase. Therefore, we used quadrupole radiation to manipulate the phase and amplitude of the light and even investigated some simple applications, including the realization of focusing light and anomalous refraction. Such a new mechanism of controlling light, combined with other methods, can provide significant insights into achieving challenging goals, like steganography and multifunctional metasurfaces. [ABSTRACT FROM AUTHOR]

We derive a coupled-mode theory (CMT) formulation for the fast analysis of periodic multi-element metasurfaces in the presence of radiation losses. Full-wave simulations of periodic multi-element metasurfaces are very time- and memory-consuming, especially as the size and complexity of the metasurface increase. The CMT formulation provides a considerably faster and efficient alternative. It results in a small system of equations with size equal to the number of supported resonator modes in the frequency range of interest, allowing to calculate the resonator mode amplitudes and, consequently, the metasurface response. Subsequently, we systematically derive analytical closed-form expressions for the coupling coefficients between two weakly coupled resonators in the presence of radiation losses and incorporate them into the CMT model, which is found important for the accurate description of the metasurface, while also providing insight into the underlying physics of complex metasurfaces. We validate the proposed formulation on benchmark examples of both metal- and dielectric-based metasurface absorbers (MSAs) by comparing the CMT results to spectral FEM simulations of the composing supercell. To further demonstrate the potential of the proposed formulation, as a proof of concept, we use the CMT to synthesize a larger optimized periodic multi-element MSA. A comprehensive comparison to full-wave FEM simulations of the composing supercell is included in terms of time and computational requirements, which shows that our method provides a valuable and efficient alternative solver for synthesizing complex metasurfaces. [ABSTRACT FROM AUTHOR]

Inspired by the local resonance mechanism, a resonant periodic structure (RS) constructed by an array of periodic floating oscillators is proposed for enhancing surface water wave attenuation. A hybrid frequency domain method is introduced for solving the linear or nonlinear initial-boundary value mixing problem. The numerical results show that the RS has a superior suppression effect on the propagation of waves in comparison with the Bragg periodic structure (BS) of the same scale. The incoming waves across the spectrum are substantially reduced by RS through the inverse propagation of radiation waves induced by the wave-driven oscillators. Furthermore, to achieve a better attenuation effect, a nonlinear resonant periodic structure which the periodic oscillators are integrated with the nonlinear stiffness mechanism (NSM) is proposed based on the idea of reducing equivalent stiffness. The motions of oscillators are regulated by the NSM, and the attenuation effect is further improved due to the modified radiation wave. The concept and results presented herein may provide forward-looking technical guidance for future coastal protection. [ABSTRACT FROM AUTHOR]

Strain plays an important role in the performance and reliability of AlGaN/GaN high electron mobility transistors (HEMTs). However, the impact of strain on the performance of proton irradiated GaN HEMTs is yet unknown. In this study, we investigated the effects of strain relaxation on the properties of proton irradiated AlGaN/GaN HEMTs. Controlled strain relief is achieved locally using the substrate micro-trench technique. The strain relieved devices experienced a relatively smaller increase of strain after 5 MeV proton irradiation at a fluence of 5 × 1014 cm−2 compared to the non-strain relieved devices, i.e., the pristine devices. After proton irradiation, both pristine and strain relieved devices demonstrate a reduction of drain saturation current (Ids,sat), maximum transconductance (Gm), carrier density (ns), and mobility (μn). Depending on the bias conditions the pristine devices exhibit up to 32% reduction of Ids,sat, 38% reduction of Gm, 15% reduction of ns, and 48% reduction of μn values. In contrast, the strain relieved devices show only up to 13% reduction of Ids,sat, 11% reduction of Gm, 9% reduction of ns, and 30% reduction of μn values. In addition, the locally strain relieved devices show smaller positive shift of threshold voltage compared to the pristine devices after proton irradiation. The less detrimental impact of proton irradiation on the transport properties of strain relieved devices could be attributed to reduced point defect density producing lower trap center densities, and evolution of lower operation related stresses due to lower initial residual strain. [ABSTRACT FROM AUTHOR]

A dual-channel thermal emitter, which is composed of an InAs layer atop an aluminum grating backed with a continuous aluminum film, is proposed and studied. Two resonant absorption and emission peaks are achieved at different wavelengths, leading to the achievement of dual-channel strong nonreciprocal radiations at two different wavelengths for an applied magnetic field of 2 T when the angle of incidence is 17°. The physical origin is revealed through illustrating the electromagnetic field distributions at both resonances and also verified through impedance matching. In addition, the perfect nonreciprocity remains stable within a wide range of structure parameters, lowering the cost of manufacture. Moreover, the nonreciprocal radiations for different incident angles and different magnetic fields are also investigated in detail. The concept and conclusions proposed here will be interesting for the development of novel energy conversion and capture devices. [ABSTRACT FROM AUTHOR]

Development of nanophotonics has made it possible to control the wavelength and direction of thermal radiation emission, but it is still limited by Kirchhoff's law. Magneto-optical materials or Weyl semimetals have been used in recent studies to break the time-reversal symmetry, resulting in a violation of Kirchhoff's law. Currently, most of the work relies on the traditional optical design basis and can only realize the nonreciprocal thermal radiation at a specific angle or wavelength. In this work, on the basis of material informatics, a design framework of a multilayer nonreciprocal thermal absorber with high absorptivity and low emissivity at any arbitrary wavelength and angle is proposed. Through a comprehensive investigation of the underlying mechanism, it has been discovered that the nonreciprocal thermal radiation effect is primarily attributed to excitation of the cavity mode at the interface between the metal and the multilayer structure. Moreover, the impact of factors, such as layer count, incidence angle, extinction coefficient, and applied magnetic field on nonreciprocal thermal radiation, is thoroughly explored, offering valuable insights to instruct the design process. Additionally, by expanding the optimization objective, it becomes feasible to design fixed dual-band or even multi-band nonreciprocal thermal absorbers. Consequently, this study offers essential guidelines for advancing the control of nonreciprocal thermal radiation. [ABSTRACT FROM AUTHOR]

We investigate the temporal correlation between very-high-frequency (VHF, at frequencies of the order of 10–100 MHz), ultrahigh-frequency (UHF, at frequencies within 1–6 GHz), and x-ray (with photon energies more than 10 keV) emissions, which accompany the development of a high-voltage discharge initiated in a long gap at voltages up to 1 MV. The x-ray and UHF emissions are found to emerge starting approximately from the prepulse current onset observed before the discharge gap breakdown and both gradually decay coming to this instant. The UHF emission spectrum is represented with frequencies up to 6 GHz, with the highest spectral power being achieved within 1–2 GHz. The radio emission power drops sharply at frequencies below 1 GHz and increases closer to 150 MHz with the highest spectral power of VHF radiation being reached within 60–90 MHz. The VHF emission can appear before the discharge current and UHF emission onsets in the form of 100-ns-long prepulses, and its intensity significantly increases as the UHF emission starts. The analysis of the temporal correlation between x rays, VHF, and UHF radiations, discharge current, and voltage waveforms indicates that the generation mechanisms of the discharge electromagnetic radiations are difficult to be interpreted in terms of the developing or colliding streamer concepts. [ABSTRACT FROM AUTHOR]

This study investigates an axial extension mode magnetoelectric antenna designed for near-field communication in dielectric cluttered environments. The antenna configuration consists of two magnetostrictive Metglas-polymer composites bonded on opposite sides of a PZT-5A actuator, creating a dumbbell configuration. Operating at its 88 kHz mechanical resonance, the antenna emits electromagnetic radiation in the near field by applying an AC voltage to the piezoelectric material, generating an acoustic wave that propagates through the volume and induces oscillating magnetizations. The design uses a system of uncoupled models: an electrostatic finite element model to predict strain that feeds into a Landau–Lifshitz–Gilbert micromagnetic model to predict magnetic moment changes and, subsequently, a dipole model to forecast near-field radiation characteristics. Measurements were conducted on the antenna's impedance, quality factor, mechanical resonance, transmitted magnetic signal strength, and radiation patterns, with variations in the bias magnetic field, frequency, and applied voltage. The results exhibit a strong correlation with model predictions, and the radiated signal strengths compare favorably with those of state-of-the-art pacemaker communication devices. Computational parametric studies using Galfenol and Terfenol-D suggest the potential for up to a three order of magnitude reduction in the antenna's volume, which is critical for implanted medical devices. [ABSTRACT FROM AUTHOR]

Varactor diodes have been proposed as active tuning elements of reconfigurable metasurfaces in the Ka-band. However, their experimental realization in this frequency range has not been demonstrated yet. We report the implementation of such a reconfigurable intelligent surface (RIS) made of 20 × 20 unit cells. By active tuning of the bias voltage of the varactors, the phase of the backward diffracted wave can be continuously tuned between 0 ° and 180 °. Thus, the phase tuning can be independently controlled for each unit cell. The frequency working range of the RIS is 1.1 GHz (from 30.6 to 31.7 GHz). As an illustration of the practical use, we demonstrate continuous beam steering of microwave radiation at 31 GHz in a defined propagation plane. [ABSTRACT FROM AUTHOR]

The radiation intensity dependence of photothermal (PT) and photocarrier (PC) signals from n-type CdSe single crystals was investigated by modulated infrared radiometry (MIRR) in the mid-IR range (5–11.3 μm) with superbandgap photoexcitation. The influence of dc temperature increase of the sample was avoided by a new step-sine modulation method that combines the advantages of transient and periodical modulation. With increasing laser intensity I, the amplitude of the PC component shows a sub-linear dependence (|SPC| ∝ I0.5), while the PT one has the expected linear dependence (|SPT| ∝ I). As a result, the transition frequency ft between the two components is shifted to higher frequencies, which is explained in the frame of a simple model. The origin of the observed effects is the decrease of the effective photocarrier lifetime τ ∝ I−0.5 over three laser intensity decades. In contrast, previous studies on nonlinear PC response in semiconductors performed in the near-IR range (0.7–1.8 μm) have found supra-linear |SPC| dependence with exponent between 1 and 2. This difference is attributed to the fact that the near-IR radiometric signal features characteristics of a photoluminescence (PL) signal that are different from those of the mid-IR PC signal, as shown in our previous study [J. Appl. Phys. 119, 125108 (2016)] on the same CdSe samples. [ABSTRACT FROM AUTHOR]

The Trinity test site was chosen, in part, for its supposed remove from human inhabitation. Yet nearly half-a-million people were living within a 150-mile radius of the explosion, with some as close as 12 miles away. None were warned or evacuated by the US government ahead of time. After the blast went off, fallout snowed down across the landscape for days, contaminating water and food sources. Children played with the hot flakes. Then pets and livestock began to die. Still, no one was told the truth, nor were government efforts made to evacuate the surrounding populations—despite warnings from Manhattan Project doctors and physicists that the radiation hazard for these civilians was, in their words, "very significant." Nearly eight decades later, Trinity test "downwinders" still await government recognition and restitution. [ABSTRACT FROM AUTHOR]

Selective infrared radiation is crucial for achieving infrared stealth and heat dissipation. Artificially designed superstructure film (SF) provides several advantages for controlling and modulating infrared radiation, making them a promising solution for these applications. The research described in this work has successfully produced broadband selective infrared radiation by using a surface made up of circular patches that are combined. Numerical simulations show that this SF can achieve broadband selective radiation with 3–5 μm mid-wave infrared (MWIR) suppression and 8–14 μm long-wave infrared (LWIR) emission. The spectral selectivity can be easily switched to high emissivity in MWIR and low emissivity in LWIR by simply changing the basal layer. The resonance mechanism for achieving broadband spectral selectivity in the SF may be due to a combination of multimode plasmon resonances that are induced by the structural nonrotational symmetry of the circular patches. By applying the selective radiation SF on the tail nozzle or the vehicle, the effect of thermal management is very significant. Selective radiation SF can reduce radiant energy in the 3−5 μm band by a significant amount at 500 °C, resulting in a 46 °C cooler temperature than that at the body without the SF. At 80 °C, radiated energy in the 8–14 μm band is also considerably reduced and the temperature is 10 °C lower than that of the body without the SF. There will be obvious advantages in potential applications for infrared stealth and heat dissipation by the designed SF, a simple and convenient manufacturing process. [ABSTRACT FROM AUTHOR]

Photonic crystal structures have attracted significant attention because of their ability to confine light, especially outgoing waves in a bandgap. In this study, we investigate a layer that can control the Smith–Purcell radiation. The results show that transmission characteristics and quality factor of a 1D photonic crystal can narrow the radiation spectrum and enhance the radiation intensity. From another perspective, the entire structure can be treated as a composite grating, the radiation spectra of which are obtained by theoretical calculations and agree with that from the analysis based on the role of the 1D photonic crystal. Therefore, it can be concluded that the radiation from a composited structure can be simplified by the radiation controlled by the 1D metal photonic crystal, and it provides a fast way to reshape the radiation spectra by designing the transmission characteristic and quality factor of the photonic crystal. Furthermore, a layer with special transmission characteristics and quality factor above a reflection grating can be used to achieve coherent and tunable Smith–Purcell radiation, which is significant for the development of band-controllable light or terahertz radiation sources. [ABSTRACT FROM AUTHOR]

In this paper, an effective equivalent modeling technique has been proposed to describe small-signal characteristics of InP-based high electron mobility transistors (HEMTs) after proton radiation, which is composed of an artificial neural network and equivalent-circuit models. Small-signal intrinsic parameters of InP-based HEMTs are extracted from S-parameters before and after 2 MeV proton radiation as modeling objects. The deep learning model of a generative adversarial network has been explored to expand the measured finite data samples. Four feedforward neural networks are incorporated to equivalent-circuit topology to form the equivalent model, which are trained to accurately predict the radiation-induced variations of Cgs, Cgd, Rds, and gm, respectively. The prediction accuracy of the developed equivalent model has been well verified in terms of the broad-band S-parameters under radiation fluence of 1 × 1014 and 5 × 1013 H+/cm2. This equivalent modeling method with characterization of radiation damage effects could provide significant guidance for the aerospace monolithic millimeter-wave integrated circuit design. [ABSTRACT FROM AUTHOR]

Nb is considered a promising candidate as a refractory element due to its high-temperature endurance, excellent thermal conductivity, and compatibility with liquid-metallic coolants in nuclear reactors. In the present study, radiation-based molecular dynamics numerical simulations were conducted in Σ 13, Σ 29, and Σ 85 symmetric tilt grain boundary models for pure Nb specimens. The stochastic high-energy collisions were modeled via large-scale atomic/molecular parallel simulator code to accurately investigate the radiation-induced defects generated in the order of picoseconds at the atomic level. The long-range embedded atom method potential and coulombic repulsive Ziegler–Biersack–Littmark potentials were smoothly overlaid for precise force-field interactions among Nb atoms. To investigate the ability to arrest the radiation-induced damage, the bi-crystal Nb specimens were irradiated at varying magnitudes of primary-knock-on atom (PKA) energies EPKA = 10 20, and 30 keV at temperature regimes 300, 600, and 900 K, respectively. The Frenkel pairs, complex linear defects, distribution of point defects as clusters, rate of defect annihilation, and temperature fluctuations within the displacement cascades of irradiated Nb specimens were comprehensively studied and reported. Here, the Nb-Σ 29 GB model survived with the lowest number of residual defects. Also, the recombination rate of the irradiated Nb specimens increases with the increase in temperature and PKA energy magnitude due to enhanced atomic mobility of the dislodged atoms. Hence, the bi-crystal Nb specimen can be favored for a radiation-tolerant material as structural components in next-generation reactors. [ABSTRACT FROM AUTHOR]

Present analysis deals with the impact of nonlinear convection on MHD non-Newtonian fluid flow considering exponentially stretched sheet through porous media. Additionally, the effects of radiation, Joule heating and energy dissipation have been taken into account. The considered flow situation of nonlinear PDEs is transmuted to nonlinear ODEs using similarity analysis. The numerical computations are derived using a fourth-order Runge–Kutta scheme with a shooting technique. Meaningful observations are discussed for velocity and energy profiles. Further, the impact of pertinent parameters considering pseudoplastic fluids (n = 0. 6) and dilatant fluids (n = 1. 3) is briefed through graphs. It is noted that the escalation in the values of the power-law index declines the velocity and energy profile. Higher values of the nonlinear parameter decline the energy profile. [ABSTRACT FROM AUTHOR]

We consider the problem of the magnetization dynamics of a nanosized ferromagnetic sample caused by the spin–orbit interaction of electrons arising in the field of an incident electromagnetic wave. We discuss the case when the frequency of the incident electromagnetic radiation is close to the frequency of the interband transitions. We show that with the use of high-power lasers, this mechanism causes the appearance of a magnetization component perpendicular to the initial magnetization of the sample. This component shows oscillations with a frequency lower than that of incident electromagnetic waves. These dynamics make possible the magnetization reversal of the sample. [ABSTRACT FROM AUTHOR]

Flows driven by photons have been studied for almost a century, and a quantitative description of the radiative forces on atoms and ions is important for understanding a wide variety of systems with outflows and accretion disks, such as active galactic nuclei (AGN). Quantifying the associated forces is crucial to determining how these outflows enable interactive mechanisms within these environments, such as AGN feedback. The total number of spectral lines in any given ion of the outflow material must be tabulated in order to give a complete characterization of this force. Here, we provide calculations of the dimensionless line force multiplier for AGN environments. For a wide array of representative AGN sources, we explicitly calculate the photoionization balance at the proposed wind-launching region above the accretion disk, compute the strength of the line-driving force on the gas, and revisit and formalize the role of the commonly used ionization parameter ξ in ultimately determining the line-driving force. We perform these computations and analyses for a variety of AGN central source properties, such as black hole mass, initial wind velocity, and number density. We find that, while useful, the ionization parameter provides an incomplete description of the overall ionization state of the outflow material. We use these findings to provide an updated method for calculating the strength of the radiative line-driving using both the X-ray spectral index Γ X and the ionization parameter. [ABSTRACT FROM AUTHOR]

We study the sensitivity of South Asian Summer Monsoon (SASM) precipitation to Southern Hemisphere (SH) subtropical Absorbed Solar Radiation (ASR) changes using Community Earth System Model 2 simulations. Reducing positive ASR biases over the SH subtropics impacts SASM, and is sensitive to the ocean basin where changes are imposed. Radiation changes over the SH subtropical Indian Ocean (IO) shifts rainfall over the equatorial IO northward causing 1–2 mm/day drying south of equator, changes over the SH subtropical Pacific increases precipitation over northern continental regions by 1–2 mm/day, and changes over the SH subtropical Atlantic have little effect on SASM precipitation. Radiation changes over the subtropical Pacific impacts the SASM through zonal circulation changes, while changes over the IO modify meridional circulation to bring about changes in precipitation over northern IO. Our findings suggest that reducing SH subtropical radiation biases in climate models may also reduce SASM precipitation biases. Plain Language Summary: Precipitation from South Asian Summer Monsoon (SASM) is of high significance to the livelihoods of over a billion people. As the global climate continues to evolve, it is essential to have a clear understanding of the possible future changes to the SASM. However, current state‐of‐the‐art climate models have difficulties in simulating climatological mean SASM precipitations. Here we study sensitivity of SASM precipitation to subtropical southern ocean radiation as one of the possible causes of SASM precipitation bias. Our experiments indicate that SASM precipitation is sensitive to southern hemisphere (SH) subtropical radiation changes particularly to those in subtropical Pacific. These findings imply that improving SH subtropical radiation biases might improve SASM precipitation simulations in climate models. Key Points: We test if biases in southern hemisphere shortwave radiation contributes to biases in South Asian summer monsoon precipitation in the CESM2Reducing incoming shortwave radiation in the subtropical southern hemisphere reduces dry biases over continental South AsiaThis effect is mostly due to forcing in the South Pacific, with less impact from the Atlantic or Indian Ocean [ABSTRACT FROM AUTHOR]

Radiative cooling and active galactic nucleus heating are thought to form a feedback loop that regulates the evolution of low-redshift cool-core galaxy clusters. Numerical simulations suggest that the formation of multiphase gas in the cluster core imposes a floor on the ratio of cooling time (t cool) to free-fall time (t ff) at min(t cool/ t ff) ≈ 10. Observations of galaxy clusters show evidence for such a floor, and usually the cluster cores with min(t cool/ t ff) ≲ 30 contain abundant multiphase gas. However, there are important outliers. One of them is Abell 2029 (A2029), a massive galaxy cluster (M 200 ≳ 1015 M⊙) with min(t cool/ t ff) ∼ 20, but little apparent multiphase gas. In this paper, we present high-resolution 3D hydrodynamic adaptive mesh refinement simulations of a cluster similar to A2029 and study how it evolves over a period of 1–2 Gyr. Those simulations suggest that A2029 self-regulates without producing multiphase gas because the mass of its central black hole (⁠|${\sim} 5 \times 10^{10} \, \mathrm{ M}_\odot$|⁠) is great enough for Bondi accretion of hot ambient gas to produce enough feedback energy to compensate for radiative cooling. [ABSTRACT FROM AUTHOR]

Near-infrared long-slit spectroscopy has been used to study the stellar population (SP) of the low luminosity active galactic nuclei (AGNs) and matched analogues (LLAMA) sample. To perform the SP fits we have employed the X-shooter simple stellar population models together with the starlight code. Our main conclusions are: The star formation history of the AGNs is very complex, presenting many episodes of star formation during their lifetimes. In general, AGN hosts have higher fractions of intermediate-age SP (light-weighted mean ages, < t > L ≲ 4.5 Gyr) when compared with their analogues (< t > L ≲ 8.0 Gyr). AGNs are more affected by reddening and require significant fractions of featureless continuum and hot dust components. The ratio between the AGN radiated energy and the gravitational potential energy of the molecular gas (E Rad/ E PG) for the AGN is compared with the < t > L and a possible anticorrelation is observed. This suggests that the AGN is affecting the star formation in these galaxies, in the sense that more energetic AGN [log(E Rad/ E PG) ≳ 3] tend to host nuclear younger SP (< t > L ≲4 Gyr). We found that the recent (t <2 Gyr) returned (recycled) stellar mass is higher in AGN than in the controls. We also provide evidence that the mass-loss of stars would be enough to feed the AGN, thus providing observational constraints for models that predict that AGN feeding is partially due to the recycled gas from dying stars. [ABSTRACT FROM AUTHOR]

This work proposes a numerical model to estimate the radiant heat feedback from the flame of a burning aluminium particle. The objective is to evaluate its role on the burning time. It rests on a detailed combustion simulation of a single particle coupled with a simple two-flux approximation for the radiant flux emitted from the oxide smoke. Radiated flux from the flame is found to be around 1 MW/m $ ^2 $ 2 for atmospheric pressures, going up to more than 5 MW/m $ ^2 $ 2 for higher pressures (30 bar). Parametric simulations show that aluminium size has a small effect while oxygen-rich atmospheres can double the radiated flux. Overall, the role of flame radiation on aluminium burning rate is calculated to lie roughly between 1 and 25%, depending on conditions. This is the first study that clearly evaluates the role of flame radiation on aluminium combustion ; in most configurations, this effect, however, remains limited. [ABSTRACT FROM AUTHOR]

In the food industry, electrical conductivity is essential for heating processes. The dependence on temperature conductivity of electricity on the outermost layers flow of the nanofluid is the main topic of this paper. Variable electrical conductivity, viscosity, thermo diffusion, thermal radiation and radiation absorption on convective heat and mass transfer flow Cuo and Al2O3-water nano-fluids confined in cylindrical annulus. The non-linear governing equations have been solved by finite element technique with quadratic approximation functions. For various parametric adjustments, the temperature, speed, and nanoconcentration have all been examined. Similar to the cylindrical wall, quantitative evaluations have been made of the surface resistance, temperature rate and mass transport. It is discovered that for both types of nanofluids, a higher thermo-diffusion effect leads to a lower concentration and Sherwood digits on the cylinders. An augment in Q1 enriches the rapidity in CuO-water nanofluidic system as well as decreases in Al2O3-water nanofluidic. Increased Q1 lowers the real temperature and nanoconcentration in both types of nanofluids. [ABSTRACT FROM AUTHOR]

Fluoroelastomer‐based composites with nano‐sized bismuth oxide (B) and/or graphite (G) as fillers were prepared and characterized using FKM type 1 fluoroelastomer as a matrix. The effects of these fillers used singly or in combination on the crosslinking process, mechanical, thermal, dynamic mechanical, electrical, optical, and high‐energy radiation attenuation properties of FKM were investigated. The results showed that graphite significantly increased the moduli E50 (MPa) of FKM/G and FKM/GB composites by 1026% and 1459%, respectively, compared to FKM. On the other hand, bismuth(III) oxide did not affect the stiffness or elongation at break of FKM significantly. Graphite also imparted electrical conductivity to FKM (10−6 Scm−1), which was reduced by bismuth oxide to 10−12 Scm−1. Furthermore, the linear attenuation coefficients (μ), half‐value layer (HVL), and tenth‐value layer (THV) of pure FKM and FKM composites were evaluated using a 137Cs (662 keV) source, revealing that FKM/B and FKM/GB composites show 47.4% and 35.8% higher μ values, respectively, than FKM. Taking into consideration that the attenuation coefficient of FKM is 10 times higher than conventional elastomers such as natural rubber, these results indicate that thin flexible shielding against high electromagnetic radiation can be achieved to protect different sensitive equipment such as electronic devices used in nuclear power plants, gamma radiation facilities, telescopes, and artificial satellites. Highlights: A fluoroelastomer‐based composite containing 40 phr of bismuth(III) oxide nanopowder presents a gamma attenuation coefficient 47.4% higher than that of the polymer matrix.A fluoroelastomer‐based composite containing bismuth(III) presents a band gap of 2.40 eV.Bismuth(III) oxide nanopowder hinders the electrical conductivity imparted by a conducting filler contained in the fluoroelastomer‐based composite.Fluoroelastomer‐based composites containing graphite or bismuth(III) oxide present enhanced mechanical and thermal properties. [ABSTRACT FROM AUTHOR]

As patient exposure to ionizing radiation from medical imaging and its risks are continuing issues, this study aimed to evaluate DNA damage and repair markers after myocardial perfusion single-photon emission computed tomography (MPS). Thirty-two patients undergoing Tc-99m sestamibi MPS were studied. Peripheral blood was collected before radiotracer injection at rest and 60–90 min after injection. The comet assay (single-cell gel electrophoresis) was performed with peripheral blood cells to detect DNA strand breaks. Three descriptors were evaluated: the percentage of DNA in the comet tail, tail length, and tail moment (the product of DNA tail percentage and tail length). Quantitative PCR (qPCR) was performed to evaluate the expression of five genes related to signaling pathways in response to DNA damage and repair (ATM, ATR, BRCA1, CDKN1A, and XPC). Mann–Whitney's test was employed for statistical analysis; p < 0.05 was considered significant. Mean Tc-99m sestamibi dose was 15.1 mCi. After radiotracer injection, comparing post-exposure to pre-exposure samples of each of the 32 patients, no statistically significant differences of the DNA percentage in the tail, tail length or tail moment were found. qPCR revealed increased expression of BRCA1 and XPC, without any significant difference regarding the other genes. No significant increase in DNA strand breaks was detected after a single radiotracer injection for MPS. There was activation of only two repair genes, which may indicate that, in the current patient sample, the effects of ionizing radiation on the DNA were not large enough to trigger intense repair responses, suggesting the absence of significant DNA damage. [ABSTRACT FROM AUTHOR]

This article comments on: Casaes PA, Ferreira dos Santos JM, Silva VC, Rhem MFK, Teixeira Cota MM, de Faria SM, Rando JG, James EK, Gross E. 2024. The radiation of nodulated Chamaecrista species from the rainforest into more diverse habitats has been accompanied by a reduction in growth form and a shift from fixation threads to symbiosomes. Journal of Experimental Botany 75, 3643–3662. [ABSTRACT FROM AUTHOR]

All non-Mimosoid nodulated genera in the legume subfamily Caesalpinioideae confine their rhizobial symbionts within cell wall-bound 'fixation threads' (FTs). The exception is the large genus Chamaecrista in which shrubs and subshrubs house their rhizobial bacteroids more intimately within symbiosomes, whereas large trees have FTs. This study aimed to unravel the evolutionary relationships between Chamaecrista growth habit, habitat, nodule bacteroid type, and rhizobial genotype. The growth habit, bacteroid anatomy, and rhizobial symbionts of 30 nodulated Chamaecrista species native to different biomes in the Brazilian state of Bahia, a major centre of diversity for the genus, was plotted onto an ITS- trnL-F -derived phylogeny of Chamaecrista. The bacteroids from most of the Chamaecrista species examined were enclosed in symbiosomes (SYM-type nodules), but those in arborescent species in the section Apoucouita , at the base of the genus, were enclosed in cell wall material containing homogalacturonan (HG) and cellulose (FT-type nodules). Most symbionts were Bradyrhizobium genotypes grouped according to the growth habits of their hosts, but the tree, C. eitenorum , was nodulated by Paraburkholderia. Chamaecrista has a range of growth habits that allow it to occupy several different biomes and to co-evolve with a wide range of (mainly) bradyrhizobial symbionts. FTs represent a less intimate symbiosis linked with nodulation losses, so the evolution of SYM-type nodules by most Chamaecrista species may have (i) aided the genus-wide retention of nodulation, and (ii) assisted in its rapid speciation and radiation out of the rainforest into more diverse and challenging habitats. [ABSTRACT FROM AUTHOR]

The plasma in cool cores of solar prominences is partially ionized and its ionization degree, in general, depends on the actual kinetic temperature and density of the plasma and the ions considered. However, we demonstrate that under typical prominence conditions, the dominant mechanism contributing to partial ionization is photoionization by radiation diffusing through the plasma. This mechanism strongly depends on the radiation illuminating prominences from the surrounding solar atmosphere. The understanding of the partial ionization of prominence plasma thus requires a complex solution of the non-LTE radiative-transfer problem. In this paper, we discuss the ionization of hydrogen, helium and some other important species. We also demonstrate the role of non-equilibrium ionization. This article is part of the theme issue 'Partially ionized plasma of the solar atmosphere: recent advances and future pathways'. [ABSTRACT FROM AUTHOR]

In this paper, we study the role of radiative cooling (RC) in a two-fluid model consisting of coupled neutrals and charged particles. We first analyse the linearized two-fluid equations where we include radiative losses in the energy equation for the charged particles. In a one-dimensional geometry for parallel propagation and in the limiting cases of weak and strong coupling, it can be shown analytically that the instability conditions for the thermal mode and the sound waves, the isobaric and isentropic criteria, respectively, remain unchanged with respect to one-fluid radiative plasmas. For the parameters considered in this paper, representative for the solar corona, the RC produces growth of the thermal mode and damping of the sound waves. In the weak coupling limit, the growth of the thermal instability and the damping of the sound waves is as derived in Field (Field 1965 Astrophys. J.142, 531 (doi:10.1086/148317)) using the charged fluid properties. When neutrals are included and are sufficiently coupled to the charges, the thermal mode growth rate and the wave damping both reduce by the same factor, which depends on the ionization fraction only. For a heating function that is constant in time, we find that the growth of the thermal mode and the damping of the sound waves are slightly larger. The numerical calculation of the eigenvalues of the general system of equations in a three-dimensional geometry confirm the analytic results. We then run two-dimensional fully nonlinear simulations that give consistent results: a higher ionization fraction or lower coupling will increase the growth rate. The magnetic field contribution is negligible in the linear phase. Ionization-recombination effects might play an important role because the RC produces a large range of temperatures in the system. In the numerical simulation, after the first condensation phase, when the minimum temperature is reached, the fraction of neutrals increases four orders of magnitude because of the recombination. This article is part of the theme issue 'Partially ionized plasma of the solar atmosphere: recent advances and future pathways'. [ABSTRACT FROM AUTHOR]

Evolutionary biology faces the important challenge of determining how to interpret the relationship between selection pressures and evolutionary radiation. The lack of morphological evidence on cross-species research adds to difficulty of this challenge. We proposed a new paradigm for evaluating the evolution of branches through changes in characters on continuous spatiotemporal scales, for better interpreting the impact of biotic/abiotic drivers on the evolutionary radiation. It reveals a causal link between morphological changes and selective pressures: consistent deformation signals for all tested characters on timeline, which provided strong support for the evolutionary hypothesis of relationship between scarabs and biotic/abiotic drivers; the evolutionary strategies under niche differentiation, which were manifested in the responsiveness degree of functional morphological characters with different selection pressure. This morphological information-driven integrative approach sheds light on the mechanism of macroevolution under different selection pressures and is applicable to more biodiversity research. Understanding quantum topological states and the nature of their topological protection is an important fundamental question. By reinterpreting a past mode-switching experiment of an exciton-polariton condensate in a lattice, this work highlights the key role of collective many-body effects leading to the topological phase unwinding. [ABSTRACT FROM AUTHOR]

ZrO2 samples were obtained using three different synthesis methods (Calcination, Co-precipitation and Hydrothermal). The samples were characterized to analyze the effect of the crystalline phase on their thermoluminescent (TL) and photoluminescent (PL) responses. The ZrO2 phase was analyzed by X-Ray diffraction (XRD) and Raman. Nanoparticle size distribution was obtained by scanning electron microscopy (SEM). For optical analysis, characterizations included absorbance measurements, where samples exhibited modifications in color centers, PL emission and experimental fluorescence lifetime decay (τexp) measurements. Additionally, their TL response was studied under UV (245nm and 385nm), and 6MV photon energy from LINAC excitation. The obtained results show the improvement of TL and PL properties due to ZrO2 phase while an amorphous ZrO2 synthesized by hydrothermal method is an excellent prospect to be used as TL material and it may be a promising scintillator material at 254nm. [ABSTRACT FROM AUTHOR]

Alkaline earth stannate is characterized by good physicochemical stability. It has been applied in the field of optical information storage by coupling photoluminescence intensity modulation and photochromic performance, which has attracted the attention of researchers. The development of alkaline earth stannate ceramics with high light intensity modulation properties and non-destructive reading of optical information is of great research value. In this study, Er3+-doped Ca 2 SnO 4 photochromic ceramics were prepared by high-temperature solid-phase reaction method. Alternating UV light irradiation and thermal stimulation, the ceramics achieve a reversible transition between light and dark gray. Er3+ doping gives the ceramics dual-mode luminescence light intensity modulation performance. When the doping amount of Er3+ is 0.01 mol, there is a maximum down-conversion luminous intensity modulation ratio of 93%, which is higher than most of the same type of photochromic materials. The photochromic behavior is explained using the capture-release model of traps for carriers, and the dual-mode luminescence light-intensity modulation behavior is analyzed through the energy transfer mechanism. The optical radiation response properties were investigated and the optimum light response wavelength is found to be 290 nm, which is related to the optical band gap E g. And the selection of the optimal light response wavelength can effectively improve the performance of photochromic and light intensity modulation. This study provides a promising strategy for performance enhancement of photochromic materials. [ABSTRACT FROM AUTHOR]

Bound state in the continuum (BIC), generally realized by structures with in-plane symmetry, has been under the spotlight in the control of the electromagnetic field. This Letter presents a terahertz metasurface that possesses broken in-plane symmetry for exciting BIC. The switch from a BIC to a quasi-BIC can be achieved through parameter modulation. According to multipolar decomposition, the BIC is constructed by the destructive interference of far-field radiation originating from the electric dipole and magnetic quadrupole. More importantly, considering that the metal material has finite conductivity, we analyze the relationship between radiation and non-radiation losses, based on the time domain coupled mode theory, which provides substantial theoretical support for the investigation of BIC phenomena. Furthermore, the proposed metasurface exciting quasi-BIC is highly sensitive to the changes in the dielectric environment, resulting in a high sensitivity of 135 GHz/RIU and a distinction between sucrose and glucose with the same solid content. As a result, our research provides a theoretical explanation of the evolution of BIC excited by the structure with broken in-plane symmetry and promotes the development of the high-performance meta-device used for sensing. [ABSTRACT FROM AUTHOR]

A cutoff low that covered central Europe in the middle of July 2021 brought heavy rainfall and severe flooding, resulting in more than 200 fatalities. This low was formed by a trough on 11 July and merged with another cutoff low around 12–13 July. Analysis of the energy budget and potential vorticity suggests that the main cutoff low was maintained through the merger with another cutoff low; this was the dominant contributor to maintenance of the main cutoff low around 12–13 July. The results of Lagrangian trajectory analyses support this conclusion. Analysis of diabatic PV modification during the merger indicates that radiation acts mainly to enhance the potential vorticity of the parcels when they move from another cutoff low into the main cutoff low, especially in the upper layer. However, that effect is not pronounced in the lower layer. These results demonstrate that cutoff lows can be maintained through a merger with another cutoff low and underline the need to consider diabatic processes when investigating mergers. Significance Statement: This study examines an upper-tropospheric cyclone called a cutoff low, which caused a high-impact weather event over Europe in the middle of July 2021, and investigates its maintenance mechanism. This cutoff low merged with another, suggesting a contribution to the maintenance. Diabatic processes during the merger are also investigated. The results of this study suggest that not only do cyclone regions merge, but diabatic modification of the vortex structure can be seen when two cutoff lows merge, and the modification process may differ in different vertical layers of the cutoff low. [ABSTRACT FROM AUTHOR]

Measurements of atmospheric structure and surface energy budgets distributed along a high-altitude mountain watershed environment near Crested Butte, Colorado, from two separate, but coordinated, field campaigns, Surface Atmosphere Integrated field Laboratory (SAIL) and Study of Precipitation, the Lower Atmosphere, and Surface for Hydrometeorology (SPLASH), are analyzed. This study identifies similarities and differences in how clouds influence the radiative budget over one snow-free summer season (2022) and two snow-covered seasons (2021/22; 2022/23) for this alpine location. A relationship between lower-tropospheric stability stratification and longwave radiative flux from the presence or absence of clouds is identified. When low clouds persisted, often with signatures of supercooled liquid in winter, the lower troposphere experienced weaker stability, while radiatively clear skies that are less likely to be influenced by liquid droplets were associated with appreciably stronger lower-tropospheric stratification. Corresponding surface turbulent heat fluxes partitioned differently based upon the cloud–stability stratification regime derived from early morning radiosounding profiles. Combined with the differences in the radiative budget largely resulting from dramatic seasonal differences in surface albedo, the lower atmosphere stratification, surface energy budget, and near-surface thermodynamics are shown to be modified by the effective longwave radiative forcing of clouds. The diurnal evolution of thermodynamics and surface energy components varied depending on the early morning stratification state. Thus, the importance of quiescent versus synoptically active large-scale meteorology is hypothesized as a critical forcing for cloud properties and associated surface energy budget variations. The physical relationships between clouds, radiation, and stratification can provide a useful suite of metrics for process understanding and to evaluate numerical models in such an undersampled, highly complex terrain environment. [ABSTRACT FROM AUTHOR]

The objective of the current study is to investigate the importance of entropy generation and thermal radiation on the patterns of velocity, isentropic lines, and temperature contours within a thermal energy storage device filled with magnetic nano-encapsulated phase change materials (NEPCMs). The versatile finite element method (FEM) is implemented to numerically solve the governing equations. The effects of various parameters, including the viscosity parameter, ranging from 1 to 3, the thermal conductivity parameter, ranging from 1 to 3, the Rayleigh parameter, ranging from 102 to 3 × 102, the radiation number, ranging from 0.1 to 0.5, the fusion temperature, ranging from 1.0 to 1.2, the volume fraction of NEPCMs, ranging from 2% to 6%, the Stefan number, ranging from 1 to 5, the magnetic number, ranging from 0.1 to 0.5, and the irreversibility parameter, ranging from 0.1 to 0.5, are examined in detail on the temperature contours, isentropic lines, heat capacity ratio, and velocity fields. Furthermore, the heat transfer rates at both the cold and hot walls are analyzed, and the findings are presented graphically. The results indicate that the time taken by the NEPCMs to transition from solid to liquid is prolonged inside the chamber region as the fusion temperature θf increases. Additionally, the contours of the heat capacity ratio Cr decrease with the increase in the Stefan number Ste. [ABSTRACT FROM AUTHOR]

Background: The use of Computed Tomography (CT) imaging data to create 3D printable patient‐specific devices for radiation oncology purposes is already well established in the literature and has shown to have superior conformity than conventional methods. Using non‐ionizing radiation imaging techniques such as photogrammetry or laser scanners in‐lieu of a CT scanner presents many desirable benefits including reduced imaging dose and fabrication of the device can be completed prior to simulation. With recent advancements in smartphone‐based technology, photographic and LiDAR‐based technologies are more readily available than ever before and to a high level of quality. As a result, these non‐ionizing radiation imaging methods are now able to generate patient‐specific devices that can be acceptable for clinical use. Purpose: In this work, we aim to determine if smartphones can be used by radiation oncologists or other radiation oncology staff to generate bolus or brachytherapy surface moulds instead of conventional CT with equivalent or comparable accuracy. Methods: This work involved two separate studies: a phantom and participant study. For the phantom study, a RANDO anthropomorphic phantom (limited to the nose region) was used to generate 3D models based on three different imaging techniques: conventional CT, photogrammetry & LiDAR which were both acquired on a smartphone. Virtual boli were designed in Blender and 3D printed from PLA plastic material. The conformity of each printed boli was assessed by measuring the air gap volume and approximate thickness between the phantom & bolus acquired together on a CT. For the participant study, photographs, and a LiDAR scan of four volunteers were captured using an iPhone 13 Pro™ to assess their feasibility for generating human models. Each virtual 3D model was visually assessed to identify any issues in their reconstruction. The LiDAR models were registered to the photogrammetry models where a distance to agreement analysis was performed to assess their level of similarity. Additionally, a 3D virtual bolus was designed and printed using ABS material from all models to assess their conformity onto the participants skin surface using a verbal feedback method. Results: The photogrammetry derived bolus showed comparable conformity to the CT derived bolus while the LiDAR derived bolus showed poorer conformity as shown by their respective air gap volume and thickness measurements. The reconstruction quality of both the photogrammetry and LiDAR models of the volunteers was inadequate in regions of facial hair and occlusion, which may lead to clinically unacceptable patient‐specific device that are created from these areas. All participants found the photogrammetry 3D printed bolus to conform to their nose region with minimal room to move while three of the four participants found the LiDAR was acceptable and could be positioned comfortably over their entire nose. Conclusions: Smartphone‐based photogrammetry and LiDAR software show great potential for future use in generating 3D reference models for radiation oncology purposes. Further investigations into whether they can be used to fabricate clinically acceptable patient‐specific devices on a larger and more diverse cohort of participants and anatomical locations is required for a thorough validation of their clinical usefulness. [ABSTRACT FROM AUTHOR]

Since 2010, there has been little published data on the state of equipment and infrastructure in veterinary radiation oncology clinical practice. These data are important not only to identify the status and use of technology within the veterinary radiation oncology community but also to help identify the extent of medical physics support. The purpose of our study is to report findings from a survey of veterinary radiation oncologists in the USA, Canada, and select centers outside of North America in 2022. A 40‐question survey covering topics such as type of radiotherapy equipment, techniques offered, treatment planning systems and dose calculation algorithms, special techniques, board‐certified radiation oncologists and residents, and extent of medical physics support was distributed through an online survey tool. Results from 40 veterinary radiation oncology institutions, with equipment explicitly used for veterinary care, suggest that the current state of practice is not dissimilar to what currently exists in human radiation oncology facilities; techniques and technologies commonly employed include flattening filter‐free mode megavoltage beams, volumetric arc therapy, daily cone‐beam computed tomography, image‐guided radiation therapy, and sophisticated dose calculation algorithms. These findings suggest the need for modern radiation oncology acceptance testing, commissioning, and quality assurance programs within the veterinary community. The increase in veterinary radiation oncology residency positions and increasing sophistication of equipment suggests that increased levels of standardized medical physics support would benefit the veterinary radiation oncology community. [ABSTRACT FROM AUTHOR]

Ray-finned fishes, which compose nearly half of living vertebrate diversity, provide an excellent system for studying the evolution of novel body forms. Lampriformes is a species-poor lineage of acanthomorph ray-finned fishes that has evolved two very different and highly specialized body plans suited to life in pelagic oceanic habitats: the deep, round-bodied bathysomes and the ribbon-like taeniosomes. Here, we present a new phylogenetic hypothesis and divergence time estimates for lampriform fishes based on an updated morphological dataset and DNA sequences from nuclear genes for all but one of the living lampriform families and 55% of recognized extant genera. Our analyses resolve two major clades in Lampriformes: the Bathysomi and the Taeniosomi. A time calibrated phylogeny shows that the origin of living lampriforms coincides with the aftermath of the Cretaceous–Palaeogene extinction and that anatomically modern pelagic morphotypes evolved 10 Myr after the start of the Palaeogene. [ABSTRACT FROM AUTHOR]

Key points: Disease severity in acute radiation rhinosinusitis (ARRS) peaks after radiation therapy.ARRS is mainly local inflammation, manifested by increased pro‐inflammatory cytokines.Intranasal corticosteroids are effective anti‐inflammatory drugs in the treatment of ARRS. [ABSTRACT FROM AUTHOR]

This study delves into investigating the influence of pH on the scintillation characteristics of YAG: Ce3+ nanoscintillators. Six sample detectors were fabricated using cerium-activated YAG powder synthesized via the sol–gel method at different pH levels. The aim is to identify the optimal pH for designing efficient radiation detectors, thus advancing radiation detection technologies. Results underscore pH's role in optimizing YAG: Ce3+ nanoscintillator performance. Synthesis at pH = 4 exhibited superior performance, with a scintillation light yield of 26384 ± 3500 ph/MeV and a fast component decay of 82 ns. These findings inform the synthesis and optimization of YAG: Ce3+ nanoscintillators, benefiting applications such as radiation detection and medical imaging. [ABSTRACT FROM AUTHOR]

This study developed methodologies for rapid screening and analysis of numerous biological samples following a radiation accident. A measurement system was established to determine the presence of internal contamination promptly. Smear screening method could distinguish contaminated patients by setting a 20% buffer zone. Gross alpha and gross beta screening method could distinguish contaminated patients by setting limit of detection (0.70, 393 cpm). Smear screening, gross alpha screening, and gross beta screening methodologies are expected to detect internal contamination quickly. While effective for screening, these methods were unsuitable for precise analysis. [ABSTRACT FROM AUTHOR]

Radiation necrosis (RN) after stereotactic radiosurgery (SRS) in brain metastases has been extensively evaluated, and RN is correlated with various risk factors. However, no study comprehensively analyzed the correlation between RN and the border zones of the brain that are vulnerable to ischemia. We hypothesized that patients with tumors in the border zone are at high risk of RN. Hence, the current study aimed to assess the correlation between border zone lesions and RN, with consideration of other predetermined factors. This retrospective study included 117 patients with 290 lesions who underwent Gamma Knife SRS. Radiological and clinical analyses were performed to identify factors possibly correlated with RN. Notably, the lesion location was classified into 2 groups (border zone and nonborder zone) based on the blood supply. In total, 22 (18.8%) patients with 22 (7.5%) lesions developed RN. Univariate analysis revealed a significant correlation between RN and external border zone lesions, second course of SRS administered at the same site of the previous SRS, prescribed dose, and tumor volume. Multivariate analysis showed that border zone lesions, second course of SRS at the same site of the previous SRS, and tumor volume were significantly correlated with RN. Patients with tumors in the border zone are at high risk of RN. The potential risks of RN can be attributed hypothetically to hypoperfusion. Hence, the association between RN and border zone lesions seems reasonable. [ABSTRACT FROM AUTHOR]

The structure of a cloud is three-dimensional (3-D). Nevertheless, cloud research is predominantly developed in one-dimensional (1-D) hypothesis from passive optical satellite measurements. Cloud retrieval algorithms typically do not consider the parallax displacement of clouds in multi-view images. Inversion of cloud properties based on two-dimensional (2-D) coordinates cannot solve multi-view radiation changes which are caused by macro-structure of a cloud in 3-D space. In this study, we included the 3-D structure of clouds by repositioning cloud pixels within a 3-D coordinate system utilizing the directional polarization camera (DPC) data before conducting cloud property retrieval. It is followed by identification of location of cloud in each observational view's image plane. Observational paths of clouds are rebuilt at each observational view. Furthermore, computer graphics methods are employed to establish spatial relationship among different cloud observational paths. The radiational and geometrical information are relocated in unified 3-D sub-pixel space. Finally, 3-D cloud radiation information could be applied to retrieve cloud properties. The case results demonstrate that our method can effectively reduce mixed pixels of clouds and clear sky by 5.79% while decrease indistinguishable pixels in cloud phase classification by 2.11%. It leads to an enhancement in the classification accuracy of water clouds and ice clouds by 3.30% and 4.03%, respectively. Therefore, it is concluded that considering the impact of cloud structure before retrieval would significantly improve accuracy. [ABSTRACT FROM AUTHOR]

Background: Ionizing radiation can induce bystander effects (RIBE), and Astragalus polysaccharides (APS) have a protective effect against RIBE. It has been proved that RIBE occurred and APS played the inhibitory effects on the RIBE when radiation was carried out only one time. However, whether RIBE happened by multiple irradiations and the effects of APS on the RIBE are unclear. This study aimed to investigate whether APS suppress RIBE damage induced by multiple irradiations. Materials and Methods: A549 cells were irradiated with 2 Gy X-rays to obtain a conditioned medium. Bone mesenchymal stem cells (BMSCs) was incubated with the conditioned medium 5 times every 3 days or APS. Cell proliferation was detected by CCK-8 and colony formation assay, and genomic instability and DNA damages were detected by the micronucleus and immunofluorescence assay. The protein associated with methylation and cancer-associated proteins in BMSCs were detected by western blot. Results: After five stimulations with a conditioned medium, the proliferative capacity of BMSCs decreased; APS pre-intervention promoted the proliferation of BMSCs. And conditional medium intervention increased the micronucleus rate and a number of 53BP1 foci; APS pre-intervention reduced the micronucleus rate and number of 53BP1 foci. In addition, the conditional medium intervention reduced the expression of methylation-related proteins and increased the expression of cancer-related proteins, while APS pre-intervention reversed this trend. Conclusion: Irradiated A549 conditioned medium can induce RIBE of BMSCs, which might be related to methylation and cancer-associated proteins and APS may block RIBE by multiple irradiations in BMSCs. [ABSTRACT FROM AUTHOR]

Summary: Static Random Access Memory (SRAM) is vital in aerospace applications, but it may experience soft errors in strong radiation environments. This paper proposes a reconfigurable radiation SRAM with two operating modes catering to different environmental requirements: (1) traditional triple modular redundancy mode used when the radiation environment is strong and (2) SRAM cell expansion mode used when the radiation is not very strong. For example, when the memory capacity of a single module is 8 k, the memory capacity is 8 k in traditional triple modular redundancy mode, but it can be tripled to 24 K in extended mode. As can be obviously seen, this design can adjust the size according to the needs. In SRAM cell expansion mode, the proposed 14T SRAM cell enables the memory to maintain radiation resistance. Compared with DICE, RHBD‐12T, and WHIT, the read speed is improved by 3.8%, 5.7%, and 11.5% respectively, but compared with WE‐QUATRO, the read speed is reduced by 1.9%. The hold static noise margin is 1.378 times than DICE, 1.201 times than WE‐QUATRO, 1.045 times than RHBD‐12T, and 1.14 times than WHIT, respectively. The proposed 14T cell in this paper exhibits the highest critical charge value compared with the other cells. Combined with the expansion mode of the reconfiguration design, it shows great stability. [ABSTRACT FROM AUTHOR]

In occupational epidemiology, the healthy worker survivor effect can manifest as a time-dependent confounder because healthier workers can accrue greater amounts of exposure over longer periods of employment. For example, in occupational studies of radiation exposure that focus on cumulative annualized radiation dose, workers can accrue greater amounts of cumulative radiation exposure over longer periods of employment, while workers with longer periods of employment can transition into jobs with a reduced potential for annualized radiation exposure. The extent to which confounding arising from the healthy worker survivor effect impacts radiation risk estimates is unknown. We assessed the impact of the healthy worker survivor effect on estimates of radiation risk among nuclear workers in a Million Person Study cohort. In simulation studies, we contrasted the ability of marginal structural Cox models with inverse probability weighting and Cox proportional hazards models to account for time-dependent confounding arising from the healthy worker survivor effect. Marginal structural Cox models and Cox proportional hazards models with flexible functional forms for duration of employment provided reliable results. It is crucial to flexibly adjust for duration of employment to account for confounding arising from the healthy worker survivor effect in occupational epidemiology. [ABSTRACT FROM AUTHOR]