An Adaptive Threshold for the Canny Edge Detection with Actor-Critic Algorithm

Visual surveillance aims to perform robust foreground object detection regardless of the time and place. Object detection shows good results using only spatial information, but foreground object detection in visual surveillance requires proper temporal and spatial information processing. In deep learning-based foreground object detection algorithms, the detection ability is superior to classical background subtraction (BGS) algorithms in an environment similar to training. However, the performance is lower than that of the classical BGS algorithm in the environment different from training. This paper proposes a spatio-temporal fusion network (STFN) that could extract temporal and spatial information using a temporal network and a spatial network. We suggest a method using a semi-foreground map for stable training of the proposed STFN. The proposed algorithm shows excellent performance in an environment different from training, and we show it through experiments with various public datasets. Also, STFN can generate a compliant background image in a semi-supervised method, and it can operate in real-time on a desktop with GPU. The proposed method shows 11.28% and 18.33% higher FM than the latest deep learning method in the LASIESTA and SBI dataset, respectively

Angiomyofibroblastoma-Like Tumor of the Scrotum

Various tumors can occur in the scrotum. Of them, angiomyofibroblastoma-like tumors are very rare mesenchymal tumors. Angiomyofibroblastoma-like tumors cannot be easily differentially diagnosed from other malignant tumors invading the male genital tract on the basis of clinical characteristics and imaging study. Therefore, surgical removal and a histopathologic diagnosis must also be performed

Optical Shaping of Plasma Cavity for Controlled Laser Wakefield Acceleration

Laser wakefield accelerators rely on relativistically moving micron-sized plasma cavities that provide extremely high electric field >100GV/m. Here, we demonstrate transverse shaping of the plasma cavity to produce controlled sub-GeV electron beams, adopting laser pulses with an axially rotatable ellipse-shaped focal spot. We showed the control capability on electron self-injection, charge, and transverse profile of the electron beam by rotating the focal spot. We observed that the effect of the elliptical focal spot was imprinted in the profiles of the electron beams and the electron energy increased, as compared to the case of a circular focal spot. We performed 3D particle-in-cell (PIC) simulations which reproduced the experimental results and revealed dynamics of a new asymmetric self-injection process. This simple scheme offers a novel control method on laser wakefield acceleration to produce tailored electron beams and x-rays for various applications.Comment: 5 pages, 5 figure

Biochemical Markers as Predictors of In-Hospital Mortality in Patients with Severe Trauma: A Retrospective Cohort Study

Background Initial evaluation of injury severity in trauma patients is an important and challenging task. We aimed to assess whether easily measurable biochemical parameters (hemoglobin, pH, and prothrombin time/international normalized ratio [PT/INR]) can predict in-hospital mortality in patients with severe trauma. Methods This retrospective study involved review of the medical records of 315 patients with severe trauma and an injury severity score >15 who were managed at Gyeongsang National University Hospital between January 2005 and December 2015. We extracted the following data: in-hospital mortality, injury severity score, and initial hemoglobin level, pH, and PT/INR. The predictive values of these variables were compared using receiver operation characteristic curves. Results Of the 315 patients, 72 (22.9%) died. The in-hospital mortality rates of patients with hemoglobin levels <8.4 g/dl and ≥8.4 g/dl were 49.8% and 9.9%, respectively (P < 0.001). At a cutoff hemoglobin level of 8.4 g/dl, the sensitivity and specificity values for mortality were 81.9% and 86.4%, respectively. At a pH cutoff of 7.25, the sensitivity and specificity values for mortality were 66.7% and 77.8%, respectively; 66.7% of patients with a pH <7.25 died versus 22.2% with a pH ≥7.25 (P < 0.001). The in-hospital mortality rates for patients with PT/INR values ≥1.4 and <1.4 were 37.5% and 16%, respectively (P < 0.001; sensitivity, 37.5%; specificity, 84%). Conclusions Using the suggested cutoff values, hemoglobin level, pH, and PT/INR can simply and easily be used to predict in-hospital mortality in patients with severe trauma

Electron energy increase in a laser wakefield accelerator using up-ramp plasma density profiles

The phase velocity of the wakefield of a laser wakefield accelerator can, theoretically, be manipulated by shaping the longitudinal plasma density profile, thus controlling the parameters of the generated electron beam. We present an experimental method where using a series of shaped longitudinal plasma density profiles we increased the mean electron peak energy more than 50%, from 175 +/- 1 MeV to 262 +/- 10 MeV and the maximum peak energy from 182 MeV to 363 MeV. The divergence follows closely the change of mean energy and decreases from 58.9 +/- 0.45 mrad to 12.6 +/- 1.2 mrad along the horizontal axis and from 35 +/- 0.3 mrad to 8.3 +/- 0.69 mrad along the vertical axis. Particle-in-cell simulations show that a ramp in a plasma density profile can affect the evolution of the wakefield, thus qualitatively confirming the experimental results. The presented method can increase the electron energy for a fixed laser power and at the same time offer an energy tunable source of electrons.© The Author(s) 201

Comparison of two automated CT perfusion software packages in patients with ischemic stroke presenting within 24 h of onset

BackgroundWe compared the ischemic core and hypoperfused tissue volumes estimated by RAPID and JLK-CTP, a newly developed automated computed tomography perfusion (CTP) analysis package. We also assessed agreement between ischemic core volumes by two software packages against early follow-up infarct volumes on diffusion-weighted images (DWI).MethodsThis retrospective study analyzed 327 patients admitted to a single stroke center in Korea from January 2021 to May 2023, who underwent CTP scans within 24 h of onset. The concordance correlation coefficient (ρ) and Bland–Altman plots were utilized to compare the volumes of ischemic core and hypoperfused tissue volumes between the software packages. Agreement with early (within 3 h from CTP) follow-up infarct volumes on diffusion-weighted imaging (n = 217) was also evaluated.ResultsThe mean age was 70.7 ± 13.0 and 137 (41.9%) were female. Ischemic core volumes by JLK-CTP and RAPID at the threshold of relative cerebral blood flow (rCBF) &lt; 30% showed excellent agreement (ρ = 0.958 [95% CI, 0.949 to 0.966]). Excellent agreement was also observed for time to a maximum of the residue function (Tmax) &gt; 6 s between JLK-CTP and RAPID (ρ = 0.835 [95% CI, 0.806 to 0.863]). Although early follow-up infarct volume showed substantial agreement in both packages (JLK-CTP, ρ = 0.751 and RAPID, ρ = 0.632), ischemic core volumes at the threshold of rCBF &lt;30% tended to overestimate ischemic core volumes.ConclusionJLK-CTP and RAPID demonstrated remarkable concordance in estimating the volumes of the ischemic core and hypoperfused area based on CTP within 24 h from onset