Optimizing focus: switchable modes and sub-diffraction spots in inverse circular Airy beams.

We report an experimental investigation into the tight-focusing characteristics of linearly polarized inverse circular Airy beams (ICABs). Our study reveals that tightly focused ICABs exhibit Bessel-like, needle-like, or dual foci profiles depending on whether the main ring's radius is smaller than, equal to, or larger than the critical radius. The emergence of the dual foci structure is attributed to the constrained entrance aperture of the microscope objective (MO). In contrast to traditional Gaussian beams (GBs), ICABs demonstrate remarkable advantages in terms of focal spot size. Notably, we observe a focal spot with a size of 245 nm, representing a 26.4% reduction compared to the diffraction limit. These unique properties open up promising avenues for potential applications in optical multi-plane particle trapping, conveying, and super-resolution optical imaging.

Meta-Analysis on the Therapeutic Effect of Transcatheter Arterial Chemoembolization Combined with Portal Vein Embolization.

INTRODUCTION: The aim of the study was to conduct a systematic review to explore the therapeutic effect of transcatheter arterial chemoembolization (TACE) combined with portal vein embolization (PVE) for patients with hepatocellular carcinoma (HCC). METHODS: Chinese and English databases (PubMed, Web of Science, Cochrane Library, China National Knowledge Infrastructure, Wanfang database, and VIP database) were searched from database inception to August 15, 2023. Studies comparing TACE combined with PVE versus TACE alone for patients with HCC were included. The degree of heterogeneity was assessed using I2 statistics and a Q test. The effect size was represented by risk ratio and mean difference (MD), and the effect size range was estimated using a 95% confidence interval (CI). RESULTS: Eight eligible studies were included in the systematic review, involving 689 participants. The results showed that the future liver residual (FLR) of patients treated with TACE combined with PVE was significantly higher than that of those treated with PVE alone (MD = 3.99%; 95% CI: 1.03-6.94). Furthermore, compared with PVE alone, TACE combined with PVE had a positive effect on disease-free survival (odds ratio [OR] = 2.16; 95% CI: 1.20-3.88), recurrence rate (OR = 0.79; 95% CI: 0.07-9.42), and complications (OR = 0.53; 95% CI: 0.30-0.96). There was no statistically significant impact on mortality with TACE combined with PVE treatment. CONCLUSION: The combination of TACE with PVE can significantly reduce the FLR of patients with HCC, with higher disease-free survival, lower recurrence rate, and fewer complications.

Controlling the Goos-Hänchen shift in a double prism structure using three-level Raman gain medium.

We propose a scheme to control the Goos-Hänchen (GH) shift of TE and TM reflected light beams in a double-prism structure, where a three-level Raman gain medium is filling the gap between the two prisms. We find that it is possible to control the GH shift in this structure by externally adjusting the optical properties of the Raman gain atomic medium while the gap width between the two prisms is fixed. Inspired by recent successful implementation of the double-prism configuration with an air gap to measure the GH shift, we expected that our proposal to control the GH shift can be achieved experimentally and used in different potential applications of the GH shift.