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Boron neutron capture therapy (BNCT) was first proposed as early as 1936, and research on BNCT has progressed relatively slowly but steadily. BNCT is a potentially useful tool for cancer treatment that selectively damages cancer cells while sparing normal tissue. BNCT is based on the nuclear reaction that occurs when 10B capture low-energy thermal neutrons to yield high-linear energy transfer (LET) α particles and recoiling 7Li nuclei. A large number of 10B atoms have to be localized within the tumor cells for BNCT to be effective, and an adequate number of thermal neutrons need to be absorbed by the 10B atoms to generate lethal 10B (n, α)7Li reactions. Effective boron neutron capture therapy cannot be achieved without appropriate boron carriers. Improvement in boron delivery and the development of the best dosing paradigms for both boronophenylalanine (BPA) and sodium borocaptate (BSH) are of major importance, yet these still have not been optimized. Here, we present a review of this treatment modality from the perspectives of radiation oncology, biology, and physics. This manuscript provides a brief introduction of the mechanism of cancer-cell-selective killing by BNCT, radiobiological factors, and progress in the development of boron carriers and neutron sources as well as the results of clinical study. [ABSTRACT FROM AUTHOR]

Fascin, an actin-bundling protein overexpressed in all carcinomas, has been associated with poor prognosis, shorter survival, and more metastatic diseases. It is believed that fascin facilitates tumor metastasis by promoting the formation of invasive membrane protrusions. However, the mechanisms by which fascin is overexpressed in tumors are not clear. TGFβ is a cytokine secreted by tumor and mesenchymal cells and promotes metastasis in many late stage tumors. The pro-metastasis mechanisms of TGFβ remain to be fully elucidated. Here we demonstrated that TGFβ induced fascin expression in spindleshaped tumor cells through the canonical Smad-dependent pathway. Fascin was critical for TGFβ-promoted filopodia formation, migration, and invasion in spindle tumor cells. More importantly, fascin expression significantly correlates with TGFβ1 and TGFβ receptor I levels in a cohort of primary breast tumor samples. Our results indicate that elevated TGFβ level in the tumor microenvironment may be responsible for fascin overexpression in some of the metastatic tumors. Our data also suggest that fascin could play a central role in TGFβ-promoted tumor metastasis. [ABSTRACT FROM AUTHOR]

In the era of artificial intelligence, accomplishing emotion recognition in human–computer interaction is a key work. Expressions contain plentiful information about human emotion. We found that the canny edge detector can significantly help improve facial expression recognition performance. A canny edge detector based dual-channel network using the OI-network and EI-Net is proposed, which does not add an additional redundant network layer and training. We discussed the fusion parameters of α and β using ablation experiments. The method was verified in CK+, Fer2013, and RafDb datasets and achieved a good result. [ABSTRACT FROM AUTHOR]

• Low selenium causes splenic injury through the p38 MAPK signaling pathway. • Novel material applications of nanosized selenium. • Selenium supplementation can reduce spleen damage. Selenium (Se) is a trace element necessary for humans to maintain normal physiological activities, and Se deficiency may lead to splenic injury, while Se supplementation can alleviate splenic injury. However, the mechanism is unclear. In this study, we constructed a Se deficiency animal model by feeding Sprague-Dawley (SD) rats with low Se feed. Meanwhile, we observed the repairing effect of Se supplementation on splenic injury with two doses of novel nano-selenium (Nano-Se) supplement by gavage. We measured the Se content in the spleens of the rats by atomic fluorescence spectroscopy (AFS) method and combined the results of hematoxylin-eosin (HE) and Masson staining to observe the splenic injury, comprehensively evaluating the construction of the animal model of low selenium-induced splenic injury. We measured the mRNA and protein expression levels of p38 mitogen-activated protein kinase (p38 MAPK), nuclear factor kappa-B (NF-κB), and interleukin-6 (IL-6) in the spleen by Real-time quantitative polymerase chain reaction (qPCR), western blot (WB), and immunohistochemistry (IHC). We found that the Se deficiency group exhibited lower Se content, splenic fibrosis, and high expression of p38 MAPK, NF-κB, and IL-6 compared to the normal group. The Se supplement groups exhibited higher Se content, attenuated splenic injury, and down-regulated expression of p38 MAPK, NF-κB, and IL-6 relative to the Se deficiency group. This study suggests that Se deficiency leads to splenic injury in rats, and Se supplementation may attenuate splenic injury by inhibiting the expression of p38 MAPK, NF-κB and IL-6. [ABSTRACT FROM AUTHOR]

A novel surface plasmon polaritons (SPPs) refractive index sensor based on a single defect nanocavity coupled with a metal-insulator-metal (MIM) waveguide is proposed and numerically simulated by using the finite difference time domain (FDTD) method with perfectly matched layer absorbing boundary condition. It is found that the defect structure can realize two Fano resonances and these two Fano resonances originate from two different mechanisms. The results demonstrate the liner correlation between the resonance wavelengths of the device and the refractive index of the material under sensing. Through the optimization of structural parameters, we achieve a theoretical value of the refractive index sensitivity as high as 1800.4 nmRIU. It could be utilized to develop ultra-compact nanodevice for high-resolution biological sensing. [ABSTRACT FROM AUTHOR]

A surface plasmon polaritons (SPPs) temperature sensor which consists of two metal–insulator–metal (MIM) waveguides coupled to each other by an ethanol-sealed rectangular cavity is proposed. The transmission characteristics of the nanodevice are theoretically analyzed and numerically simulated by two-dimension finite difference time domain (FDTD) method. The temperature sensing characteristics of the SPPs waveguide sensor are systematically analyzed by investigating the transmission spectra. The results indicate that the position of the transmission peak wavelengths has a linear relationship with the ambient temperature. The temperature sensitivity increases with the increase of the cavity length and decrease of the cavity height. The temperature sensitivity of the nanometeric sensor can reach as high as −0.65 nm/°C. It could be utilized to develop ultracompact temperature sensor for high integration. [ABSTRACT FROM AUTHOR]

Abstract: A novel two-dimensional nanoscale structure for sensing which consists of a metal–insulator–metal (MIM) waveguide with a defect, is designed and numerically simulated by using the finite element method (FEM). Both of the refractive index sensing characteristics and the temperature sensing characteristics of the structure are analyzed systematically by investigating the transmission spectrum. The numerically simulated results show that the dip positions of the transmission spectrum have linear relationships with the refractive index of the material under sensing and the ambient temperature, respectively. Based on the relationships, the refractive index of the material under sensing or the ambient temperature can be obtained from the dip wavelength shift detection. When the width and the height of the defect are set to be 50nm, 300nm, respectively, the refractive index sensitivity can be obtained as high as 1736nmRIU−1 and the temperature sensitivity is about 0.51nm/°C with a FOM of 9.79. This work has a certain significance for designing nanoscale refractive index sensors and temperature sensors. [Copyright &y& Elsevier]

Highlights: [•] Ca(1 − x) Sr x Cu3Ti4O12 ceramics are synthesized by sol–gel process. [•] Positron annihilation lifetime spectra is used to investigate the defects of samples. [•] Nonlinear and dielectric properties are controlled by density and defects of samples. [Copyright &y& Elsevier]