The absolute branching fraction of $D^+ \to \mu^+ \nu$ has been directly measured by an analysis of a data sample of about 33 ${\rm pb^{-1}}$ collected around $\sqrt{s}=3.773$ GeV with the BES-II at the BEPC. At these energies, $D^-$ meson is produced in pair as $e^+e^-\to D^{+} D^{-}$. A total of $5321 \pm 149 \pm 160$ $D^-$ mesons are reconstructed from this data set. In the recoil side of the tagged $D^-$ mesons, $2.67\pm1.74$ purely leptonic decay events of $D^+ \to \mu^+ \nu$ are observed. This yields a branching fraction of $BF(D^+ \to \mu^+ \nu_{\mu}) = (0.122^{+0.111}_{-0.053}\pm 0.010)%$, and a corresponding pseudoscalar decay constant $f_{D^+}=(371^{+129}_{-119}\pm 25)$ MeV.
Abstract The plasma-fluid multi-physics process of a spark plasma jet igniter is studiednumerically. The plasma discharge, gas heating, mass, and heat transfer processes in one working cycle are modeled and analyzed. Gas discharge starts inside the igniter, the ‘ladder-like’ dielectric wall structure promotes the transition of a volumetric discharge to a surface discharge, establishing a conductive path between the electrodes over a timescale of tens of nanoseconds. Once the electrodes are short-circuited, a new spark-arc discharge channel forms, heating the gas up to 7000–10 000 K in the discharge channel and 2000–4000 K in the igniter. The gas molecules are dissociated and pushed out of the igniter, forming a ‘heating core’ with high temperature (2000–3000 K) and chemical activity following a wavefront propagating with a velocity of 750–875 m s −1 . The calculated evolution of the heating core agrees well with the ICCD measurements. It is found that the ‘ladder-like’ structure does not affect the penetration depth or expansion radius of the heating core, but leads to a complex vortical flow that allows for chemical activity species to be brought out into the ambient gas.
Recent years have witnessed the advancement of deep learning vision technologies and applications in the medical industry. Intelligent devices for specific medication management could alleviate workload of medical staff by providing assistance services to identify drug specifications and locations.In this work, object detectors based on the you only look once (YOLO) algorithm are tailored for toxic and narcotic medication detection tasks in which there are always numerous of arbitrarily oriented small bottles. Specifically, we propose a flexible annotation process that defines a rotated bounding box with a degree ranging from 0° to 90° without worry about the long-short edges. Moreover, a mask-mapping-based non-maximum suppression method has been leveraged to accelerate the post-processing speed and achieve a feasible and efficient medication detector that identifies arbitrarily oriented bounding boxes.Extensive experiments have demonstrated that rotated YOLO detectors are highly suitable for identifying densely arranged drugs. Six thousand synthetic data and 523 hospital collected images have been taken for training of the network. The mean average precision of the proposed network reaches 0.811 with an inference time of less than 300 ms.This study provides an accurate and fast drug detection solution for the management of special medications. The proposed rotated YOLO detector outperforms its YOLO counterpart in terms of precision.
Abstract Introduction A randomized, double-blind, cross-over, placebo-controlled clinical study with pyridostigmine bromide (PYD) in obstructive sleep apnea (OSA) patients ranging from mild to moderate disease was conducted to evaluate its clinical efficacy and safety. Methods Six diagnosed male patients with averages of age 48 yr (38 - 57 yr), BMI 28 (26 - 33), AHI 19.2 (15 - 26.2), minimum oxygen saturation (Min SaO2) 81% (75 - 87%) were enrolled to the study. The study consisted one-night acclimatization period followed immediately by a 2-night double-blind treatment period when subjects received either a single dose of PYD (a cholinesterase inhibitor, 90 mg) or placebo before sleep. Subjects were required to maintain in a supine position, and monitored by a standard polysomnography all the time. Sleep questionnaires (The SMH Sleep Questionnaire and ESS) were taken daily immediately after sleep and at the evening to evaluate the sleep satisfaction and the day-time quality, respectively. Safety of the drug was monitored and evaluated. Results Reductions of AHI (28.1%, p < 0.01), apnea index (37.2%, p < 0.05), % of total apnea/hypopnea time (36.4%, p < 0.05) were observed in the treatment group compared with the placebo between 2-7 hours of sleep. Min SaO2 was increased, no change, or decreased by PYD in 3, 2, or 1 subject(s), respectively. PYD was generally well tolerated with minimum minor incidents. Subjects reported to have more satisfied sleep and more clear-headed in the treatment night, and more energy, more concentrated and less sleepy during the daytime following the treatment night. Conclusion This study demonstrated the initial effectiveness of the PYD treatment for OSA, indicating that it may provide a new treatment option if the efficacy can be maintained in a large-scale clinical trial. Support N/A
Abstract The corona bar induced pre–ionization is a crucial preliminary process in the operation of ArF excimer lasers, directly impacting the uniformity and stability of output laser. The ultraviolet corona pre–ionization, as the mainstream method, is tightly coupled with the main discharge process, which complicates analysis. Here, we establish a numerical model of a single pulse discharge incorporating an external circuit to analyze the pre–ionization process and its influence on the breakdown characteristics. (1) By adopting detailed input parameters of photoionization model, we observe uniform and dispersed plasma propagation from the corona bar to the main gap. (2) An artificial boundary condition is proposed to investigate the phenomenological effect of high–energy electrons emission, emphasizing the influence of surface discharge along the cathode. (3) The propagation and breakdown characteristics of the two pre–ionization setup methods, photoionization and background electron density, are compared numerically. This study enhances the understanding of the pre–ionization process in ArF excimer lasers and provides theoretical insights for their optimization and design.