Numerical design and characterization of a novel parallel beam combined lens based on X-ray capillary optics.

A novel parallel beam combined lens (PBCL) was designed based on a parabolic monocapillary x-ray lens (PMXRL). The proposed PBCL converted a divergent X-ray beam into a near-solid parallel one, which retains the low divergence characteristics of PMXRL and significantly improves the intensity gain by about one order of magnitude. Compared with the traditional polycapillary parallel x-ray lens (PPXRL), the divergence performance of this lens is improved by an order of magnitude, and the light intensity gain is improved by 3-4 times. In addition, we developed a MATLAB-based visualization tool to simulate X-ray transmission within the PBCL through ray tracing. This tool facilitated the assessment of the PBCL's transmission efficiency and its comparison with conventional PMXRL and the PPXRL. The transport process of the PBCL is systematically investigated under the comprehensive consideration of multiple parameters. This study provided a new idea and theoretical basis for the further development of X-ray modulation technology.

Magnified x ray ghost imaging with tapered polycapillary optics free of the penumbra effect.

X ray ghost imaging (XGI) offers both radiation dose-reduction potential and cost-effective benefits owing to the utilization of a single-pixel detector. Most XGI schemes with laboratory x ray sources require a mechanically moving mask for either structured illumination or structured detection. In either configuration, however, its resolution remains limited by the source size and the unit size of the mask. Upon propagation, the details of the object can actually be magnified by the divergence of x rays, but at the same time, the penumbra effect produced by the finite source size is dramatically intensified, which ultimately leads to a degradation of image quality in XGI. To address these limitations, this work proposes a magnified XGI scheme using structured detection equipped with tapered polycapillary optics, which can efficiently suppress the object's penumbra as well as resolve the magnified details of the object. In general, the resolution of this scheme is no longer affected by the source size but by the microcapillary size of polycapillary. Our work fundamentally achieves cancellation of penumbra effect-induced aberration, thus paving the way for high-resolution magnified XGI.

MiR-718 mediates the indirect interaction between lncRNA SEMA3B-AS1 and PTEN to regulate the proliferation of hepatocellular carcinoma cells.

It has been reported that SEMA3B-AS1 is a tumor-suppressive lncRNA in gastric cardia adenocarcinoma. We explored the possible involvement of SEMA3B-AS1 in hepatocellular carcinoma (HCC). We found that SEMA3B-AS1 was downregulated in HCC tissues compared with noncancer tissues and was not affected by hepatitis B virus (HBV) and hepatitis C virus (HCV) infections. In addition, SEMA3B-AS1 expression was not affect by cancer development, and low SEMA3B-AS1 levels were closely correlated with poor survival. SEMA3B-AS1 in HCC tissues was inversely correlated with microRNA (miR)-718 and positively correlated with PTEN. In HCC cells, SEMA3B-AS1 overexpression resulted in upregulated, while miR-718 overexpression resulted in downregulated phosphatase and tensin homolog (PTEN) expression. In addition, miR-718 overexpression attenuated the effects of SEMA3B-AS1 overexpression. SEMA3B-AS1 and PTEN overexpression resulted in a reduced proliferation rate of HCC cells, while miR-718 overexpression resulted in an increased rate. In addition, miR-718 overexpression attenuated the effects of SEMA3B-AS1 overexpression. Therefore, miR-718 may mediate the indirect interaction between lncRNA SEMA3B-AS1 and PTEN to regulate the proliferation of hepatocellular carcinoma cells.