Electromagnetic wave absorption and mechanical properties of SiC nanowire/low-melting-point glass composites sintered at 580°C in air

Si C nanowires are excellent high-temperature electromagnetic wave (EMW) absorbing materials. However, their polymer matrix composites are difficult to work at temperatures above 300℃, while their ceramic matrix composites must be prepared above 1000℃ in an inert atmosphere. Thus, for addressing the abovementioned problems, SiC/low-melting-point glass composites were well designed and prepared at 580℃ in an air atmosphere. Based on the X-ray diffraction results, SiC nanowires were not oxidized during air atmosphere sintering because of the low sintering temperature. Additionally, SiC nanowires were uniformly distributed in the glass matrix material. The composites exhibited good mechanical and EMW absorption properties. As the filling ratio of SiC nanowires increased from 5wt%to 20wt%, the Vickers hardness and flexural strength of the composite reached HV 564 and 213 MPa, which were improved by 27.7%and 72.8%, respectively, compared with the low-melting-point glass. Meanwhile, the dielectric loss and EMW absorption ability of SiC nanowires at 8.2–12.4 GHz were also gradually improved. The dielectric loss ability of low-melting-point glass was close to 0. However, when the filling ratio of SiC nanowires was 20wt%, the composite showed a minimum reflection loss (RL) of-20.2 dB and an effective absorption (RL≤-10 dB) bandwidth of2.3 GHz at an absorber layer thickness of 2.3 mm. The synergistic effect of polarization loss and conductivity loss in SiC nanowires was responsible for this improvement.

Screening and identification of HLA-A2-restricted neoepitopes for immunotherapy of non-microsatellite instability-high colorectal cancer

Colorectal cancer has one of the highest mortality rates among malignant tumors,and most patients with non-microsatellite instability-high (MSI-H) colorectal cancer do not benefit from targeted therapy or immune checkpoint inhibitors.Identification of immunogenic neoantigens is a promising strategy for inducing specific antitumor T cells for cancer immunotherapy.Here,we screened potential high-frequency neoepitopes from non-MSI-H colorectal cancer and tested their abilities to induce tumorspecific cytotoxic T cell responses.Three HLA-A2-restricted neoepitopes (P31,P50,and P52) were immunogenic and could induce cytotoxic T lymphocytes in peripheral blood mononuclear cells from healthy donors and colorectal cancer patients.Cytotoxic T lymphocytes induced in HLA-A2.1/K^(b) transgenic mice could recognize and lyse mutant neoepitope-transfected HLA-A2^(+) cancer cells.Adoptive transfer of cytotoxic T lymphocytes induced by the peptide pool of these three neoepitopes effectively inhibited tumor growth and increased the therapeutic effects of anti-PD-1 antibody.These results revealed the potential of high-frequency mutation-specific peptide-based immunotherapy as a personalized treatment approach for patients with non-MSI-H colorectal cancer.The combination of adoptive T cell therapy based on these neoepitopes with immune checkpoint inhibitors,such as anti-PD-1,could provide a promising treatment strategy for non-MSI-H colorectal cancer.

Visible-light responsive organic nano-heterostructured photocatalysts for environmental remediation and H2 generation

The ease of molecular design and functionalization make organic semiconductors(OSCs)unit the electronic,chemical and mechanical benefits with a material structure.The easily tunable optoelectronic properties of OSCs also make it promising building blocks and thereby provide more possibilities in photocatalytic applications.So far,organic nanostructures have gained great impetus and found wide applications in photocatalytic organic synthesis,remediation of water and air,as well as water splitting into hydrogen.But they still suffer from low charge separation and sunlight absorption efficiencies.Accordingly,many strategies have been explored to address these issues,and one of the most effective solutions is to develop nano-heterostructures.To give an impulse for the developments of this field,this review attempts to make a systematic introduction on the recent progress over the rational design and fabrication of organic nano-heterostructured photocatalysts,including the types of organic semiconductor/semiconductor(OSC/SC),organic semiconductor/metal(OSC/M),organic semiconductor/carbon(OSC/C),and OSC-based multinary nano-heterostructures.The emphasis is placed on the structure/property relationships,and their photocatalytic purposes in environmental and energy fields.At last,future challenges and perspectives for the ongoing development of OSC materials and their use in high-quality optoelectronic devices are also covered.