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The primary objective of this study is to investigate hadronic molecules of K ⁎ K ¯ 1 (1270) using a one-boson-exchange model, which incorporates exchanges of vector and pseudoscalar mesons in the t -channel, as well as the pion exchange in the u -channel. Additionally, careful consideration is given to the three-body effects resulting from the on-shell pion originating from K 1 (1270) → K ⁎ π. Then the BESIII data of the J / ψ → ϕ η η ′ process is fitted using the K ⁎ K ¯ 1 (1270) scattering amplitude with J P C = 0 − − or 1 − −. The analysis reveals that both the J P C = 0 − − and 1 − − assumptions for K ⁎ K ¯ 1 (1270) scattering provide good descriptions of the data, with similar fit qualities. Notably, the parameters obtained from the best fits indicate the existence of K ⁎ K ¯ 1 (1270) bound states, denoted by ϕ (2100) and ϕ 0 (2100) for the 1 − − and 0 − − states, respectively. The current experimental data, including the η polar angular distribution, cannot distinguish which K ⁎ K ¯ 1 (1270) bound state contributes to the J / ψ → ϕ η η ′ process, or if both are involved. Therefore, we propose further explorations of this process, as well as other processes, in upcoming experiments with many more J / ψ events to disentangle the different possibilities. [ABSTRACT FROM AUTHOR]

As epoxy resin (EP) is widely used in the microelectronic field, it is essential to improve its electromagnetic wave (EMW) absorption and flame retardancy simultaneously. In this work, we synthesized a novel nanohybrid, RMN (Fe 3 O 4 /NHS@M(OH)(OCH 3)@rGO (M = Co, Ni)), with petal-shaped anisotropic interfaces, by using graphene oxide as the core and the 2D nanosheets M(OH)(OCH 3) (M = Co, Ni) as the petal, with nickel hydroxystannate and ferrite as further modifications. The RMN combines carbon-based materials, ferrites and conductors, and represents the petal-like structure with rich nondirectional interfaces. The results show that EP composite containing 25 wt% RMN represented excellent EMW absorption, with a minimum reflection loss of −55.79 dB (with 7.4 mm thickness at 3.1 GHz). Moreover, the EP composite with 15 wt% RMN (EP/RMN700-3) had the lowest peak heat release rate of 470.9 kW m−2, which was 69.7 % lower than pure EP, showing a significantly improving in flame retardant. The thermal conductivity efficiency of EP/RMN700-3 increased to 128.4 % compared with the pure EP, which effectively reduces fire risk caused by heat accumulation. This study provides a valuable solution to overcome the challenges of EMW absorption and flame retardant for EP in the microelectronic materials field. [Display omitted] • The nonoriented petal-like structure provides rich interface. • Carbon materials, ferrites and conductors support the multiple absorbing mechanisms. • EMW absorption, flame retardant and thermal management suit for electronic packaging. [ABSTRACT FROM AUTHOR]

Fire alarm systems are essential for protecting lives and properties from fire hazards. However, most of the existing fire alarm nanopapers rely on the resistance reduction after heating, which requires direct contact with the flame. In this study, we present a novel fire alarm nanopaper (CMPA) based on heat-triggered shape recovery. The CMPA is composed of hydroxypropyl methyl cellulose (HPMC) as the matrix and 2D nanomaterials M(OH)(OCH 3) as fillers. When the temperature of CMPA exceeded the glass transition, the thrice-folded CMPA-1.0 flattened in 30s and connected to the alarm circuit based on its conductive surface. According to the results, the CMPA-1.0 with a thickness of about 0.2 mm had an efficient electromagnetic shielding of 42.1 dB. Moreover, the CMPA-1.0 self-extinguished rapidly after being ignited with its original shape preserved. The peak heat release rate of CMPA-1.0 was 108.9 W/g, which was 61.9 % lower than that of HPMC. Furthermore, the thermal conductivity of CMPA-1.0 reached to 0.317 W m−1 K−1, which was 40.8 % higher than that of HPMC, reducing the heat accumulation effectively. This work shows that CMPA is an ideal material for sensitive and safe early fire alarm, and the strategy based on heat-triggered shape recovery is promising in fire alarm application. [ABSTRACT FROM AUTHOR]

In this paper, a numerical simulation method is used to study the process of multiple droplets impact on the wall of a liquid droplet radiator in a space environment. The effects of droplet spacing, droplet velocity, wall properties and other factors on the evolution of droplet impact on the wall are analyzed. The results show that the critical Reynolds number of droplets without splashing decreases and then remains unchanged as the droplet spacing of silicone oil increases. Thin liquid film promotes droplet splashing, while thick liquid film inhibits droplet splashing. The larger the initial incident velocity of the droplets, the larger the number of splashing droplets and the smaller their diameters. The critical Reynolds number of silicone oil droplets decreases monotonously with the increase of the inclination angle between the wall and the vertical direction. Finally, a 15° frustum of a cone model is chosen to simulate the actual working process of the liquid droplet radiator to verify the conclusions. The results of the study can provide guidance for the optimal design of droplet collectors. • Studying how droplet features and wall properties affect droplet impact on surface. • Analyzing how liquid film thickness affects splashing type and droplet state. • Exploring how surface tension and viscosity impact splash formation. • Identifying droplet collector parameters based on dimensionless number variation. • Results offer theoretical support for optimal droplet collector design. [ABSTRACT FROM AUTHOR]

• Identification of miRNA biomarkers in DCC and LC blood samples. • Accurate diagnosis of DCC using miRNA-based logistic regression model. • Potential of three microRNAs as DCC biomarkers and therapeutic targets. • Insights into molecular mechanisms underlying DCC progression from miRNA analysis. Decompensated cirrhosis (DCC) is a more advanced stage of liver cirrhosis (LC). It is important to identify biomarkers to predict DCC progression. The aim of this study was to analyze microRNA (miRNA) profiles of whole blood involved in the DCC process to gain a better understanding of the molecular mechanisms underlying its development. RNA-Seq analysis of blood samples from a discovery set, including four DCC patients and four LC individuals, was performed to identify differentially expressed miRNAs. The selected differentially expressed miRNAs were validated by using an independent validation set. In this study, a total of 1,036 miRNAs were identified in whole blood samples. Forty differentially expressed miRNAs were identified, including 24 upregulated and 16 downregulated miRNAs. The expression levels of three upregulated miRNAs (hsa-miR-20b-5p, hsa-miR-421, and hsa-miR-1307-3p) and two downregulated miRNAs (hsa-miR-139-5p and hsa-miR-150-5p) were validated by quantitative reverse transcriptase polymerase chain reaction. The receiver operator characteristic curve for the logistic regression model based on hsa-miR-20b-5p, hsa-miR-421, and hsa-miR-150-5p could distinguish DCC patients with excellent diagnostic accuracy (area under the curve: 0.981, p < 0.01). The miRNA expression profiles in patients with DCC and LC controls suggested that miR-20b-5p, miR-421, and miR-150-5p could be potential biomarkers and therapeutic targets for this condition. [ABSTRACT FROM AUTHOR]

Radon measurement is crucial in assessing the damage to the human body caused by natural radiation. Pulsed ionization chambers are effective for real-time radon measurement and have widespread applications in other radiation techniques. However, due to practical constraints such as limited space and portability concerns, it becomes imperative to consider not only the detection efficiency but also their ease of transportation. This work utilizes the Geant4 Monte Carlo simulation toolkit to characterize the detection models of small cylindrical and flat plate-type pulsed ionization chambers, and carry out a simulation study to analyze the three crucial factors that influence detection efficiency, including the geometry of the chamber, electrode size, and operating temperature. The results indicate that the cylindrical pulse ionization chamber, with a length of 8 cm and radius of 2 cm, has the best detection efficiency and portability in terms of geometric dimensions, achieving a detection efficiency of (58 ± 4)%. Meanwhile, the flat plate pulse ionization chamber, with dimensions of 7 cm in length and 3 cm in width, achieves the best detection efficiency and portability, with a detection efficiency of (54 ± 3)%. In terms of electrode wire size, the cylindrical ionization chamber electrode wire with a length of 7 cm and a radius of 2.5 mm was optimal with a detection efficiency of (59 ± 4)%. In terms of operating temperature, the detection efficiency of the flat-plate pulsed ionization chamber was the highest at 30 °C, which was (58 ± 4)%, and that of the cylindrical pulsed ionization chamber was the highest at 20 °C, which was (63 ± 4)%. By analyzing the influencing factors of the detection efficiency of the pulsed ionization chamber, it has a certain reference value and guiding significance for the research and design of small pulsed ionization chamber detectors for radon measuring instruments. • A portable small pulsed ionization chamber was studied for radon measurement. • The factors affecting detection efficiency for radon measurement were simulated base on the Geant4 toolkit. • A parameters scheme for the detection efficiency optimization of the ionization chamber under various factors was proposed. [ABSTRACT FROM AUTHOR]