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Radium is the most common source of alpha radiation exposure to humans and non-human species in the environment but the dosimetry is complicated by the decay chain which involves gamma exposure due to radon daughters. This paper seeks to determine the separate contributions of alpha and gamma doses to the total dose and total direct and non-targeted effect in a fish and a human cell line. This study aimed to isolate the effect of alpha particles following exposure to low doses of radium in cells, and their progeny which received no further exposure. This was initially done by comparing the survival values of a human keratinocyte cell line (HaCaT) and an embryonic Chinook salmon cell line (CHSE-214) exposed to gamma radiation, from survival of the same cell lines exposed to mixed alpha and gamma radiation through exposure to Ra-226 and its decay products. A Monte Carlo simulation was later performed to determine the contributions of radium decay products including radon daughters. The human cell line showed increased radioresistance when exposed to low doses of alpha particles. In contrast the fish cell line, which demonstrated radioresistance to low dose gamma radiation, showed increased lethality when exposed to low doses of alpha particles. Significant and complex levels of non-targeted effects were induced in progeny of irradiated cells. The simulation showed that gamma and beta decay products did not contribute significant dose and the highest beta dose was below the threshold for inducing non-targeted effects. The results confirm the need to consider the dose-response relationship when developing radiation weighting factors for low dose exposures, as well as the need to be aware of possible cell line and species differences. [ABSTRACT FROM AUTHOR]

Dynamic vision sensor (DVS) imaging quality is significantly affected by pixel noise and temporal contrast (TC), which is inversely proportional to sensitivity. To reduce the noise event rate and improve sensitivity in bright‐light conditions in the DVS pixel circuit, this paper proposes improvements to the conventional DVS pixel circuit. The proposed DVS pixel circuit adopts stacked medium‐threshold transistors instead of a single high‐threshold transistor in the photoreceptor and introduces a threshold switching circuit. Compared with the conventional DVS pixel circuit, this design increases event threshold normalized by root mean square (RMS) noise voltage, reducing the dim‐light noise bandwidth. Additionally, it achieves higher sensitivity in bright‐light conditions compared with dim‐light conditions. The proposed DVS pixel circuit is implemented in a 110‐nm complementary metal‐oxide semiconductor (CMOS) process. Post‐simulation results show that, for photocurrents between 5 fA and 100 pA, the proposed DVS pixel circuit achieves a 35 Hz peak event rate at 15% TC, which is reduced to 3.1% of the conventional structure. For photocurrents exceeding 30 pA, the proposed structure can switch TC from 15% to 5%, maintaining a noise event rate below 0.1 Hz. [ABSTRACT FROM AUTHOR]

The oil and gas phase behavior of high temperature is complex and changeable, which is usually obtained by PVT experiments. The accuracy of the experiment data plays a crucial role in the reserve evaluation and development plan of oil and gas reservoirs. However, the current PVT experiment consistency checks are not suitable for high-temperature reservoir conditions. This paper proposes a systematic check method for the PVT experiment data consistency at high temperature. These checks revise the material balance method, Hoffman method, and equilibrium constant method by using the equilibrium constant calculation method at high temperature. The consistency check of component data and constant volume depletion experiment data is carried out by combining the three improved methods with the component check method, so as to judge the experiment data accurately. In this paper, two high-temperature reservoir fluids—gas condensate sample fluid X and volatile oil sample fluid Y—are selected to carry out consistency checks with component data and constant volume depletion data. This check method is of great significance to study the phase behavior of formation oil and gas at high temperature, especially for volatile oil and gas condensate fluid. [ABSTRACT FROM AUTHOR]

The inflow of foreign R&D has brought vigor and vitality to the development of the high-tech industry (HTI). Using the panel data of HTI in 23 provinces (autonomous provinces and municipalities) in China from 2007 to 2016, this paper firstly calculates the Moran index of HTI's innovation performance (IP), and finds a spatial agglomeration effect. After rigorous testing, we determine the most suitable spatial metering model. Finally, the spatial effect is further decomposed into three kinds of effects: direct effect, indirect effect, and total effect. This paper studies the impact of foreign research and development (R&D) on IP of HTI and its spatial spillover effects. According to the research, foreign R&D has a significant role in promoting IP of HTI in China, and has specific spatial spillover effects. Significantly, foreign R&D has substantial positive spillover effects of space. When IP of HTI is measured by product innovation, there is no obvious space overflow. However, panel regression showed a significant positive effect. In terms of the influence on product IP of HTI, foreign R&D plays an almost equal role as local R&D. In terms of the impact on technological IP of HTI, foreign R&D input plays a positive role. It has a spatial spillover effect, the degree of impact is lower than that of domestic R&D input. Local governments should formulate relevant policies to encourage the fluidity of technical knowledge and overcome the sticky problem of foreign R&D technical knowledge, which is an essential aspect of absorbing foreign R&D technical knowledge in the future. [ABSTRACT FROM AUTHOR]

Hyperspectral image (HSI) denoising plays an important role in image quality improvement and related applications. Convolutional neural network (CNN)-based image denoising methods have been predominant due to advances made in the field of deep learning in recent years. Spatial and spectral information are crucial to HIS denoising, along with their correlations. However, existing methods fail to consider the global dependence and correlation between spatial and spectral information. Accordingly, in this article, we propose a novel dual-attention denoising network to overcome these limitations. We design two parallel branches to process the spatial and spectral information separately. The position attention module is applied to the spatial branch to formulate the interdependencies on the feature map, while the channel attention module is applied to the spectral branch to simulate the spectral correlation before the two branches are combined. A multiscale structure is also employed to extract and fuse the multiscale features following the fusion of spatial and spectral information. Experimental results on simulated and real data substantiate the superiority of our method both visually and quantitatively when compared with state-of-the-art methods. [ABSTRACT FROM AUTHOR]

The urgent requirement of environment-friendly materials with excellent energy storage performance for pulse power systems has sparked considerable research on lead-free ceramics. In this work, a new lead-free 0.90(0.80NaNbO3–0.20Sr0.7Bi0.2TiO3)–0.10BaSnO3 ceramic with high recoverable energy storage density (Wr = 3.51 J/cm3) and decent energy storage efficiency (η = 70.85%) has been obtained. In particular, these ceramics exhibit an ultrahigh breakdown strength of 402 kV/cm due to the dense microstructure and small grain size. The impedance analysis also reveals that the incorporation of BaSnO3 is conducive to the enhancement of insulation ability and breakdown strength. Additionally, great thermal stability (ΔWr < 10% over 20–120 °C at 200 kV/cm) and fatigue resistance (ΔWr < 1% after 120,000 electrical cycles at 200 kV/cm) are observed, indicating that the 0.90(0.80NaNbO3–0.20Sr0.7Bi0.2TiO3)–0.10BaSnO3 ceramics have promising application prospect for high-temperature energy storage devices in pulse power applications. [ABSTRACT FROM AUTHOR]

Polysaccharide-based thermo-responsive material was prepared by grafting PNIPAAm onto hybrid alginate beads, in which a biomineralized polyelectrolyte layer was constructed aiming to enhance the mechanical strength and ensure higher graft efficiency. XPS results demonstrated that the incorporation of PNIPAAm to the hybrid beads was successful, and the PNIPAAm-grafted beads were more hydrophilic than the ungrafted ones as indicated by their swelling behavior. The drug release behaviors revealed that the grafted beads were both thermo- and pH-sensitive, and the PNIPAAm existed in the pores of the alginate beads acted as the 'on-off' gates: the pores of the beads were covered by the stretched PNIPAAm to delay the drug release at 25°C and opened to accelerate the drug release at 37°C because of the shrinking of PNIPAAm molecules. This paper would be a useful example of grafting thermo-responsive polymers onto biodegradable natural polymer substrate. The obtained beads provide a new mode of behavior for thermo-responsive 'smart' polysaccharide materials, which is highly attractive for targeting drug delivery system and chemical separation. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Acknowledgment of reviewers, 2020 The Editors and Publisher would like to thank the individuals listed below who have served as reviewers for manuscripts submitted to the journal in 2020. [Extracted from the article]