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Understanding the rapid dynamics of the primary streamer is crucial for comprehending the nanosecond pulsed discharge process. To reveal the fast primary streamer process, this study introduces a newly developed quadruple emICCD camera system capable of capturing a sequence of four discharge images in single pulse, coupled with self-customized software for data analysis. A nanosecond pulse power with its FWHM of 10.5 ns was applied to a coaxial reactor, focusing on the dynamics of the primary streamer. Our research clarifies the spatiotemporal variations of the primary streamer's properties and examines their relation with inner electrode diameter (i.d. 0.2–2.0 mm). Results showed that in a pulse-powered coaxial electrode, there are three stages in the primary streamer process and that i.d. serves as an important factor influencing the formation and propagation of streamers. Interestingly, we found that streamer head velocity, streamer width, and streamer area for individual streamers remain constant prior to streamer channels reaching the outer electrode. Furthermore, we also observed an initial increase followed by a decrease in both streamer head velocity and streamer width with increasing i.d values. This study sheds light on the fundamental properties of the primary streamer during nanosecond pulsed discharge, contributing valuable insights for future plasma applications. [ABSTRACT FROM AUTHOR]

The enhancement of plasma generation in atmospheric pressure dielectric barrier discharge (DBD) is gaining increasing interest for various plasma applications. In this paper, the effect of surface charges moving with the rotating dielectric plate on improving the generation of streamer channels is investigated by a statistical analysis of electrical measurements, optical diagnostics, and numerical simulation in a needle-plate DBD device with a rotating dielectric plate. Results suggest that rotating the dielectric plate can improve the spatiotemporal distribution of streamer channels by inducing a bending of the streamer channels and an increase in the number of discharges. Statistical results show that the number of current pulse and discharge energy are increased by 20% and 47%, respectively, at the rotating speed of 160 rps (revolution per second). Based on the interaction between the applied electric field and the electric field induced by surface charges, a formula is proposed to govern the effect of rotating the dielectric plate on the discharge energy and streamer bending. To further understand the mechanism of the influence of rotating the dielectric plate on plasma properties, a 2D fluid model is implemented, and the reduced electric field and streamer propagation are analyzed. Results show that the effective transfer and reuse of surface charges play an important role in the enhancement of plasma generation. [ABSTRACT FROM AUTHOR]

Adenoid cystic carcinoma (ACC) and basal cell adenoma (BCA) share many histological characteristics and often need a differential diagnosis in clinical pathology. Recently, we found homeobox protein engrailed‐1 (EN1) was a potential diagnostic marker for ACC in an organoids library of salivary gland tumors (SGTs). Here we aim to confirm EN1 as a differential diagnostic marker for ACC, and further investigate the regulatory mechanism and biological function of EN1 in tumor progression. The transcriptional analysis, quantitative polymerase chain reaction, Western blot and immunohistochemistry staining were performed and revealed that EN1 was specifically and highly expressed in ACC, and accurately differentiated ACC from BCA. Furthermore, TGFβ signaling pathway was found associated with ACC, and the regulation of EN1 through TGFβ was detected in the human ACC cell lines and patient‐derived organoids (PDOs). TGFβ‐induced EN1 was important in promoting tumor budding in the PDOs model. Interestingly, a high level of EN1 and TGFβ1 in the budding tips was observed in ACC clinical samples, and the expression of EN1 and TGFβ1 in ACC was significantly associated with the clinical stage. In summary, our study verified EN1 is a good diagnostic marker to differentiate ACC from BCA. TGFβ‐induced EN1 facilitates the tumor budding of ACC, which might be an important mechanism related to the malignant phenotype of ACC. [ABSTRACT FROM AUTHOR]

This paper is devoted to studying the continuity of the solution map for the Cauchy problem of the Whitham equation. First, the continuity dependence of solution is established in B2,rs$\mathrm{B}^{s}_{2,r}$ in the sense of Hadamard. Next, by constructing approximate solutions, we show that the data‐to‐solution map is not uniformly continuous in Besov spaces B2,rs$\mathrm{B}^{s}_{2,r}$ (s>32,1≤r≤∞$s>\frac{3}{2}, 1\le r\le \infty$) on the periodic case and on the line. The crucial technical tool used to prove this result is Lemma 5.1, which generalizes the result of Lemma 3 in [23]. [ABSTRACT FROM AUTHOR]

With the enhancement of the sensitivity of gravitational wave (GW) detectors and capabilities of large survey facilities, such as the Vera Rubin Observatory Legacy Survey of Space and Time (LSST) and the 2.5 m Wide Field Survey Telescope (WFST), we now have the potential to detect an increasing number of distant kilonova (KN). However, distinguishing KN from the plethora of detected transients in ongoing and future follow-up surveys presents a significant challenge. In this study, our objective is to establish an efficient classification mechanism tailored for the follow-up survey conducted by WFST, with a specific focus on identifying KN associated with GW. We employ a novel temporal convolutional neural network architecture, trained using simulated multi-band photometry lasting for 3 days by WFST, accompanied by contextual information, i.e., luminosity distance information by GW. By comparison of the choices of contextual information, we can reach 95% precision and 94% recall for our best model. It also performs good validation of photometry data on AT2017gfo and AT2019npv. Furthermore, we investigate the ability of the model to distinguish KN in a GW follow-up survey. We conclude that there is over 80% probability that we can capture true KN in 20 selected candidates among ∼250 detected astrophysical transients that have passed the real–bogus filter and cross-matching. [ABSTRACT FROM AUTHOR]

Discharge dynamics of primary and secondary streamers in a repetitively pulsed surface dielectric barrier discharge (SDBD) are investigated based on experimental and numerical simulations. Plasma propagation and coupled energy of the primary streamer are restricted in subsequent pulses, but the deposited energy of the secondary streamer increases. When the pulse repetition frequency reduces, a longer plasma length and higher average velocity of the primary streamer can be observed, but the influences on propagation length and velocity of the secondary streamer are very limited. These phenomena indicate that the residual surface charges left by the previous pulse should have a critical effect on the discharge dynamics of subsequent discharges. In order to have a deeper insight into the influence of residual surface charges in a repetitively pulsed SDBD, a numerical model characterized with a pre-charging of homogeneous charge accumulated on the dielectric surface is built. Pre-charging of positive charges deposited on the dielectric surface can inhibit the electric field of applied voltage, resulting in a decrease in the expansion of the primary streamer and the positive peak of current, which is in qualitative agreement with the experimental measurements. However, there is an opposite evolution rule when the negative charges are deposited on the dielectric surface. Although the electric field strength of the secondary streamer is enhanced for a high pre-charging value, there is no great impact on the negative peak of current during the secondary streamer due to the remaining heavy mass ions. [ABSTRACT FROM AUTHOR]