A new formulation of a tissue-equivalent polymer-gel dosimeter for the measurement of three-dimensional dose distributions of ionizing radiation has been developed. It is composed of aqueous gelatin infused with acrylamide and N, N'-methylene-bisacrylamide monomers, and made hypoxic by nitrogen saturation. Irradiation of the gel, referred to as BANG, causes localized polymerization of the monomers, which, in turn, reduces the transverse NMR relaxation times of water protons. The dose dependence of the NMR transverse relaxation rate, R2, is reproducible (less than 2% variation) and is linear up to about 8 Gy, with a slope of 0.25 s(-1)Gy(-1) at 1.5 T. Magnetic resonance imaging may be used to obtain accurate three-dimensional dose distributions with high spatial resolution. Since the radiation-induced polymers do not diffuse through the gelatin matrix, the dose distributions recorded by BANG gels are stable for long periods of time, and may be used to measure low-activity radioactive sources. Since the light-scattering properties of the polymerized regions are different from those of the clear, non-irradiated regions, the dose distributions are visible, and their optical densities are dependent on dose.

In this letter, we demonstrate a passively Q-switched Ho3+/Pr3+ co-doped fluoride fiber laser centered at 2865.7 nm using a tungsten disulfide (WS2) saturable absorber (SA) for the first time, to the best of our knowledge. A multilayer WS2 film was fabricated using the sulfidation grown method and then transferred onto an Au mirror to act as the cavity feedback and SA device in a linear cavity. Under a launched pump power of 318.5 mW, stable Q-switched pulses with an average output power of 48.4 mW were achieved with a pulse duration of 1.73 µs and repetition rate of 131.6 kHz, resulting in a pulse energy of 0.37 µJ. Our experimental results confirm that WS2 can be an effective nonlinear modulator that is suitable for pulse generation at the 3 µm waveband.

Lung cancer causes severe health problems worldwide and, in China, besides being the principal cause of mortality among urbanites, it is the second leading cause of mortality in the rural population, preceded by hepatocellular carcinoma. Between 80 and 85% of lung cancer is classified as non-small cell lung cancer (NSCLC). The high mobility group box 1 (HMGB1) protein serves an important function in the tumor microenvironment and antitumor response, and may be targeted by microRNA (miR). In the present study, miR-129-5p was identified to target HMGB1 and miR-129-5p exhibited low expression levels in NSCLC tissues. Overexpression of miR-129-5p inhibited cell proliferation and promoted cell apoptosis. In conclusion, the results of the present study suggested the inhibitory function of miR-129-5p and revealed a novel therapeutic target for further investigation.

A microwave (MW) treatment of plantation eucalyptus (Eucalyptus urophylla) wood was investigated by applying MW treatments with varying conditions, such as radiation power, irradiation time, and initial moisture content of the wood. The wood permeability and drying properties were investigated. Results show that the permeability (both along the transverse and longitudinal directions) increased with the radiation power and the irradiation time. The permeability was considerably enhanced by the MW pretreatments, which effectively decreased the moisture content within the wood. A MW pretreatment can greatly accelerate the drying rate and shorten the wood drying time. Under atmospheric pressure the stain uptake along the transverse and longitudinal directions, with respect to the wood fibers, increased to 58% and 135%, respectively, compared to reference samples. Meanwhile, the drying rate increased to 171% and the drying time was cut by 65%. The MW pretreatment was found to generate a high-pressure internal steam that resulted in the rupture of wood cell pore membranes and ray cells. Therefore, a remarkable permeability increase and drying time reduction was achieved, which created favorable conditions for the fabrication of high value-added functional wood-based composites materials.

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In order to develop wide-band low-loss windows for W-band vacuum electronic devices and easily fabricate them, symmetric and asymmetric pillbox windows are investigated and reported in this paper. A symmetric pillbox window and an asymmetric pillow-box window were designed, simulation optimized, fabricated, and tested. The initial parameters for the two pillbox windows were designed by equivalent circuit theory. Computer simulation technology (CST) three-dimensional (3D) electromagnetic simulation software was used to verify and optimize the design. Because of the uncontrollability of welding during the experiment, this article provides two solutions. One is to measure and reprocess the symmetrical pillbox window with the dielectric sheet welded to reduce the influence of welding on the measurement results; the other is an asymmetrical box window which is designed to avoid the error caused by the welding of the box window. The best experimental results for the symmetric pillbox window were |S21| close to 1 dB and reflection parameter |S11| close to 10 dB in the frequency range of 77–110 GHz. The experimental results for the asymmetric pillbox window were |S21| < 1 dB nearly in the frequency range of 76–109.5 GHz. The experimental results show that both solutions efficiently complete the design of broadband pillbox windows and would potentially be operated in the gigahertz millimeter-wave region.