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The crosstalk phenomenon and its influence in the determination of gross α and β radioactivity when using a low background gas-flow proportional counter as a measuring instrument was examined in this paper. The crosstalk ratio between α and β channel was measured by using a series of α, β metal planar sources, powder sources, and thin-layer surface sources. The β-to-α crosstalk ratio of 90Sr-90Y metal planar sources and powder sources containing 14C, 137Cs, 90Sr-90Y, or 40K is less than 0.1%, which can be negligible. The crosstalk ratios of α metal planar source in ascending order are 210Po, 209Po, 239Pu, 239Pu-241Am mixed source, and 241Am, which range from 3.49% to 25.4%. The crosstalk ratio of 241Am is significantly higher than those of other sources. Furthermore, 241Am powder sources' crosstalk ratio increases with mass thickness. The crosstalk of α particles to β channel is obvious and related to the sample source preparation method. This is mainly due to the difference in self-absorption due to different source preparation methods. Overall, the crosstalk ratio of α powder sources is larger than thin-layer surface sources and metal planar sources. The interference of α-to-β crosstalk should be considered. By covering the sample sources with aluminum foil or paper with a certain thickness, the crosstalk interference of α-to-β can be reduced effectively. Additionally, it is an effective way to directly correct the count rate by the crosstalk ratio. In this case, it is necessary to consider the consistency of the sample source to be measured and the crosstalk ratio scale source, as any discrepancies can lead to a significant deviation in the corrected result.

Background210Bi is one of the most important interferences in the analysis of 90Sr by extractive chromatography. It is verified by the leaching curve that bismuth and yttrium are completely adsorbed on the chromatographic column in the bis(2-ethylhexyl) phosphate (HDEHP) extraction chromatography, and this two components can not be completely separated, resulting in higher measurement results of 90Sr.PurposeThis study aims to provide a modified method to eliminate 210Bi interference in the analysis of 90Sr by bis(2-ethylhexyl) phosphate (HDEHP) extraction chromatography.MethodsBy collecting the eluent, measuring the content of strontium, yttrium, lead and bismuth in the eluent and drawing the leaching curve, the adsorption and elution behavior of strontium, yttrium, lead and bismuth in the P204 resin were investigated. The residual 210Bi after column separation was experimentally removed by Bi2S3 precipitation or by measuring the sample source repeatedly and correcting the result with formulas.ResultsThe experimental results show that the relative deviation between the modified 90Sr activity and the reference value is within 23% when the activity ratio of 210Bi to 90Sr is not bigger than 5. The results of 90Sr calculated by the modified method for environmental samples are in good agreement with the measured results after bismuth removal by Bi2S3 precipitation.ConclusionsThe interference of 210Bi in the analysis of 90Sr by extractive chromatography can be eliminated by measuring the sample source repeatedly and correcting the result with formulas.

Semiconductor nanowires (NW) hold great promise for micro/nanolasers owing to their naturally formed resonant microcavity, tightly confined electromagnetic field, and outstanding capability of integration with planar waveguide for on-chip optoelectronic applications. However, constrained by the optical diffraction limit, the dimension of semiconductor lasers cannot be smaller than half the optical wavelength in free space, typically several hundreds of nanometers. Semiconductor NW plasmonic lasers provide a solution to break this limitation and realize deep sub-wavelength light sources. In this review, we summarize the advances of semiconductor NW plasmonic lasers since their first demonstration in 2009. First of all, we briefly look into the fabrication and physical/chemical properties of semiconductor NWs. Next, we discuss the fundamentals of surface plasmons as well as the recent progress in semiconductor NW plasmonic lasers from the aspects of multicolor realization, threshold reduction, ultrafast modulation, and electrically driven operations, along with their applications in sensing and integrated optics. Finally, we provide insights into bright perspectives and remaining challenges.

Aiming at the restriction of the Moire signal quality on the subdivision multiple and accuracy, a time domain subdivision method for optical grating signals based on time series analysis is proposed. The relationship between the grating pitch and the sampling period is utilized to transform the equal space intervals into time series. A time domain prediction model is established based on the autoregressive model of time series analysis to predict the sampling time, and the parameters of the model are calculated using the maximum likelihood estimate method. Experimental results indicate that the subdivision errors both achieve ± 2.4'' when the subdivision multiples are 400 and 800, respectively. This subdivision method reduces the reliance on grating signal quality, proving certain application value. 摘要: 针对光栅细分倍数和精度受到莫尔条纹信号质量限制的问题,提出一种基于时间序列分析的光栅信号时 域细分方法.首先利用等空间间隔的栅距与采样时间周期的对应关系,将空间栅ìié 转换为时间序列.然后利用时间 序列分析中的自回归模型进行建模预测,并采用最大似然估计法计算模型参数.最后在预测时间内发送出代表位 移的细分脉冲.实验表明,细分倍数为400 或800 时的角位移细分误差均为:t 2.4'' ,且光栅运动加速度及其变化率 越小,细分误差越小.此细分方法一定程度上降低了对光栅信号质量的依赖,具有一定的应用价值.中图分类号: TH7 文献标志码:A 文章编号: 1672-6030(2018)01-0048-06 Keywords: optical grating, space-time conversion, time domain subdivision, time series, 关键词: 光栅, 时空转换, 时域细分, 时间序列

The association between the recently updated cardiovascular health (CVH) assessment algorithm, the Life’s Essential 8 (LE8), and all-cause mortality among adults with depression remains unknown. From the National Health and Nutrition Examination Survey (NHANES) spanning 2005–2018, a cohort of 2,935 individuals diagnosed with depression was identified. Their CVH was evaluated through the LE8 score system. The investigation of mortality status utilized connections with the National Death Index up to December 31, 2019. To assess the impact of CVH on mortality risk, Kaplan-Meier survival analysis and Cox proportional hazards models, adjusting for variables related to demographics and socioeconomic status, were applied. Among 2,935 participants, those with higher CVH levels had significantly lower all-cause mortality compared to those with lower CVH levels. Cox regression analyses demonstrated that each 1-point increase in CVH score was associated with a lower risk of all-cause mortality [HR = 0.97, 95%CI:0.96–0.98]. The inverse association between CVH and mortality persisted across different demographic and socioeconomic subgroups. Higher CVH levels were associated with a significantly lower risk of all-cause mortality in individuals with depression. These findings underscore the importance of comprehensive CVH management as part of healthcare strategies for people with depression, suggesting that improving CVH may contribute to longer life expectancy in this vulnerable population. [ABSTRACT FROM AUTHOR]

The adaptive immune system has two types of plasma cells (PC), long-lived plasma cells (LLPC) and short-lived plasma cells (SLPC), that differ in their lifespan. In this paper, we propose that LLPC is crucial to the clearance of viral particles in addition to reducing the viral basic reproduction number in secondary infections. We use a sequence of within-host mathematical models to show that, CD8 T cells, SLPC and memory B cells cannot achieve full viral clearance, and the viral load will reach a low positive equilibrium level because of a continuous replenishment of target cells. However, the presence of LLPC is crucial for viral clearance. [ABSTRACT FROM AUTHOR]

Continuously manipulating the resonant wavelength of lasing modes within a large spectral range is of great significance for expanding device functionality. Here, to synthesize a single CsPbClxBr3‐x perovskite microwire with the energy bandgap gradient spanning from 2.33 to 2.83 eV along the length direction defined as the axis by using the vapor‐phase anion exchange method is proposed. A high‐quality (≈103), wide range (≈60 nm), and continuously tunable single‐mode laser is achieved in as‐prepared perovskite microwire alloy, which provides both gain media and microresonator. Simultaneously, the exciton recombination dynamics and atomic‐scale interdiffusion mechanisms at different components are clarified through time‐resolved photoluminescence (PL) spectra and theoretical calculations. The vacancy defects have a significant impact on the interdiffusion of halogen anions, excitonic recombination lifetime, and fluorescence quantum efficiency. The work provides a new strategy for the construction of new‐type broadband tunable lasers and high‐precision microspectrometers. [ABSTRACT FROM AUTHOR]

Strain engineering, as a non‐chemical tuning knob, can enhance the performance of semiconductor devices. Here, an efficient manipulation of light emission is revealed in thin‐layered 2D perovskite strongly correlated to layer numbers of [PbI6]4− octahedron (n) and [C6H5(CH2)2NH3]2(CH3NH3)n‐1PbnI3n+1 (N) by applying uniaxial strains (ɛ) via bending the flexible substrate. As increases from 1 to 3, an efficient light emission redshift (ɛ from −0.97% to 0.97%) is observed from bandgap shrinkage, and the shrinkage rate increases from 1.97 to 10.38 meV/%, which is attributed to the predominant uniaxial intralayer deformation due to the anisotropy of the [PbI6]4− octahedron lattice strain. Conversely, as increases from 7 to 48 for n = 3, the deformation related to bandgap shrinkage rate is more prominent in small‐N flakes ( ≈ 7, 15.2 meV/%) but is easily offset in large‐N flakes ( ≈ 48, 7.7 meV/%). This anisotropic lattice deformation, meanwhile, inevitably modulates the carrier recombination dynamics of [C6H5(CH2)2NH3]2(CH3NH3)n‐1PbnI3n+1, which is essential for the development of highly efficient photoelectronic devices. [ABSTRACT FROM AUTHOR]

Interest in flexible photonics has been motivated by the development of artificial smart skins. In particular, coupling of photonics and mechanics can offer opportunities to realize ultrasensitive strain sensor, however, low‐cost fabrication of flexible sensing device with desired photonic functionality remains a challenge. Hereby, the study reports an ultrasensitive strain‐gauge sensor based on the poly(ethylenenaphthalate (PEN))/monocrystal Au/MgF2/CsPbBr3 nanorod/Al2O3/polyacrylonitrile (in short P/mAu/M/CPB@Al2O3@PAN), which are sensitive to nanoscale structure alterations of PEN substrate via the stress response of the single‐mode laser based on the piezoelectric‐effect. Wherein a low‐threshold single‐mode lasing (Pth ≈ 170 nJ cm−2) is achieved through coating Al2O3 on the CsPbBr3 nanorod, producing the higher quality factor (Q ≈ 1637) to guarantee a much higher sensitivity in sensing application. Reversible spectral regulating of ≈3 nm in single‐mode‐lasing wavelength, with a subnanometre scale resolution <0.4 nm and the wavelength sensitivity (Sλ) as high as 160 nm RIU−1, is validated in response to applied strain ranging from −1.31% to 1.31%. This work not only represents essential progress in construction of ultrasensitive and cost‐effective flexible photonic sensor, but also lays the foundation for the potential application in smart photonic skins. [ABSTRACT FROM AUTHOR]

Poly(L‐lactic acid) (PLLA), as a green, biodegradable polymer material, has garnered considerable attention due to its ease of processing and exceptional properties. However, the inherent slow crystallization rate and brittleness of PLLA substantially restrict its extensive applications across various domains. In present work, PLLA and poly(D‐lactide) (PDLA)‐modified cellulose nanocrystals (CNCs), referred as CNC‐g‐L and CNC‐g‐D, are serving as nano‐fillers to enhance the crystallization rate of PLLA. Our findings demonstrate that both nano‐fillers could enhance the crystallization rate of PLLA, but the CNC‐g‐D shows a more efficient nucleation agent compared with its counterpart, CNC‐g‐L. Isothermal crystallization analysis indicates that CNC‐g‐D substantially increases nucleation density of PLLA, with pronounced crystallization at an elevated temperature of 155°C as confirmed by differential scanning calorimetry (DSC) and polarized optical microscopy (POM). Wide‐angle x‐ray diffraction (WAXD) analysis shows the preformation of stereocomplex crystals on the CNC‐g‐D surface may result in a fast crystallization rate. Meanwhile, after incorporation of different nano‐fillers, the toughness property of PLLA has also been significantly enhanced. Our result has shown the CNC‐g‐D could serve as an efficient nucleation agent toward PLLA and also facilitate to aiding in establishing comprehensive structure–property relationships of polymer materials. [ABSTRACT FROM AUTHOR]

Epstein–Barr virus (EBV), a common gamma herpesvirus, establishes a life‐long latent infection in the host to defend against innate immune recognition, which is closely related to a variety of malignant tumors, but its specific mechanism is unclear. BFRF3, an EBV‐encoded small capsid protein, is mainly involved in the assembly of the viral capsid structure and the maintenance of its stability. Here, we showed that BFRF3 can inhibit TNF‐α‐mediated NF‐кB promoter activation. Moreover, BFRF3 downregulates NF‐кB‐mediated promoter activation and transcription of inflammatory cytokines, including IL‐6 and IL‐8. Dual‐luciferase reporter assay demonstrated that BFRF3 restrains NF‐кB promoter activity at or below the p65 level, and coimmunoprecipitation analysis revealed that BFRF3 not only interacts with p65 but also binds to its critical truncated Rel homology domain (RHD) and transcriptional activation domain (TAD). However, BFRF3 does not affect the dimerization of p65‐p50, but overexpression of BFRF3 reduces the nuclear accumulation of p65, and the phosphorylation of p65 (Ser536) is repressed during BFRF3 transfection and EBV lytic infection, which promotes the proliferation of EBV. Overall, our study suggested that BFRF3 may play a crucial role in antiviral immunity to defend against EBV infection by inhibiting NF‐κB activity. [ABSTRACT FROM AUTHOR]

Heightened lactate production in cancer cells has been linked to various cellular mechanisms such as angiogenesis, hypoxia, macrophage polarisation and T‐cell dysfunction. The lactate‐induced lactylation of histone lysine residues is noteworthy, as it functions as an epigenetic modification that directly augments gene transcription from chromatin. This epigenetic modification originating from lactate effectively fosters a reliance on transcription, thereby expediting tumour progression and development. Herein, this review explores the correlation between histone lactylation and cancer characteristics, revealing histone lactylation as an innovative epigenetic process that enhances the vulnerability of cells to malignancy. Moreover, it is imperative to acknowledge the paramount importance of acknowledging innovative therapeutic methodologies for proficiently managing cancer by precisely targeting lactate signalling. This comprehensive review illuminates a crucial yet inadequately investigated aspect of histone lactylation, providing valuable insights into its clinical ramifications and prospective therapeutic interventions centred on lactylation. [ABSTRACT FROM AUTHOR]

In order to prevent accidents caused by battery aging, accurately predicting the remaining useful life (RUL) is a critical and highly challenging task in battery management systems. This article describes a lithium-ion battery RUL prediction method based on a hybrid model of CEEMD-SE-IPSO-LSSVM. This method integrates various technologies and algorithms, enhancing the accuracy and practicality of predictions. Initially, the complete ensemble empirical mode decomposition (CEEMD) is utilized to decompose the raw data into multiple intrinsic mode functions, aiding in denoising and feature extraction. Subsequently, the sample entropy (SE) is used to assess the complexity and irregularity of the data, merging intrinsic mode function components with similar SE values into a new component. Building upon this, the advanced iterative particle swarm optimization (IPSO) algorithm refines the parameters of the least squares support vector machine (LSSVM) model, improving the predictive performance of the model. Finally, through iterative training and refinement of the LSSVM model, accurate prediction of the remaining life of lithium-ion batteries is achieved. This hybrid model approach integrates data processing, feature extraction, and model refinement, resulting in a significant improvement over the baseline model with a 69.5% increase in mean absolute percentage error and a 49.4% decrease in root mean squared error, providing a robust solution for predicting the remaining life of lithium-ion batteries. [ABSTRACT FROM AUTHOR]