Current Issue : July-September Volume : 2026 Issue Number : 3 Articles : 5 Articles
Microwave ablation (MWA) represents a highly effective and clinically significant therapeutic modality for the treatment of liver metastases. The proliferation of disseminated tumor cells within the peri-necrotic transition zone (TZ) is a critical factor contributing to the postablative recurrence; to date, no effective method has been identified to specifically target and eliminate these cells. Here, based on an experimental liver metastases model, we leverage single-cell RNA sequencing and flow cytometry analysis, which reveals that TZ exhibits a VEGF-mediated immunosuppressive microenvironment, characterized by a significant increase of CD155+ myeloid cells. We further report the development of engineered cell membrane vesicles encapsulating Bevacizumab, which are fused with TIGIT-expressing membranes and platelet membranes (referred to as Bev@TPNVs). The Bev@TPNVs can specifically target the liver and the TZ, inhibit neovascularization, and restore the anti-tumor functionality of CD8+ T cells. Our findings demonstrate that Bev@TPNVs can effectively suppress liver metastasis after MWA. The intrahepatic metastasis burden is reduced by approximately 10-fold compared with the control group, and the survival rate of mice within 70 days reaches 50%. This work has the potential to establish a novel standard treatment paradigm that could revolutionize combined immunotherapy following liver metastasis ablation....
This paper proposes an optoelectronic oscillator (OEO)-based scheme for generating frequency-doubled binary phase-coded microwave pulses. The architecture employs a cascaded dual-polarization quadrature phase shift keying modulator (DP-QPSK) and a polarization modulator (PolM) to generate carrier-suppressed ±2nd-order sidebands and an orthogonally polarized optical carrier. By applying opposite phase modulation to the two polarization components and subsequently converting them into the same polarization state using a polarization controller (PC) and a polarizer, frequency-doubled phase-coded microwave pulses are obtained after photodetection. The operating principle of the scheme is theoretically analyzed and experimentally validated. A 5 GHz OEO signal is successfully converted into a 10 GHz phase-coded microwave pulse without the use of an external electronic frequency multiplier or an additional intensity modulator for pulse carving. Binary phase-coded pulses with coding rates of 0.1 Gb/s and 0.25 Gb/s are experimentally demonstrated. The measured temporal waveforms, recovered phase information, and autocorrelation results agree well with theoretical predictions. The proposed scheme provides a structurally simple and frequency-doubling solution for OEO-based phase-coded microwave pulse generation with reduced system complexity....
This study investigates the humidity sensing characteristics of microwave sensors coated with polyvinyl alcohol/carboxymethyl cellulose (PVA/CMC) composites with different weight percentages. The microwave sensor has a band-stop filter characteristic and consists of a microstrip transmission line with an interdigital capacitor-defected ground structure (IDC-DGS). To evaluate performance, PVA/CMC composites were prepared in 100/0 (pure PVA), 90/10, 80/20, 60/40, and 0/100 (pure CMC) weight percentages. The humidity sensing capability of the IDC-DGS-based microwave sensors coated with the PVA/CMC composites with different weight percentages was compared by measuring the variations in the resonant frequency and magnitude level of the transmission coefficient. The relative humidity (RH) was changed from 40% to 90% with increments of 10% at a temperature around 25 ◦C. The experimental results demonstrate that the humidity sensing capability of the microwave sensor in terms of the variations in the resonant frequency and magnitude level of the transmission coefficient increased as the weight percentage of CMC content increased. Pure CMC shows enhanced humidity sensing performance compared to gelatin and PVA in terms of the percent relative frequency shift and effective relative permittivity....
The tucumã-do-Amazonas (Astrocaryum aculeatum) is a fruit that is native to the Amazon region and known for its high content of β-carotene, phenolic compounds, and unsaturated fatty acids, making it a promising candidate for the development of functional products. However, conventional thermal methods can degrade heat-sensitive compounds. This study evaluated the application of microwave-assisted extraction in the production of tucumã nectar, aiming to maximize the retention of β- carotene and preserve the physicochemical and functional characteristics as well as the bioactive compounds of the product. Using a central composite rotational design, the optimal extraction conditions were 122.99W for 63.28 s, which resulted in higher β-carotene retention (0 111 ± 0 003 mg/g). Microwave treatment also stood out for better preservation of volatile compounds such as β-(E)-ocimene and hexenal, as well as maintaining a suitable pH (6.52), light color (ΔE < 0 7), and lipid profile, with oleic acid as the predominant fatty acid (82.93%). Compared to conventional heating, microwave heating showed lower thermal degradation and greater efficiency in preserving the bioactive compounds. It is concluded that this technology shows potential as an alternative for processing functional nectars derived from Amazonian fruits, preserving their bioactive compounds and functional properties....
Microwave sintering technology is widely regarded as one of the most promising construction techniques for in situ resource utilization in lunar bases due to its high energy efficiency and unique heating mechanism. However, the extremely low-temperature environment on the lunar surface creates a transient temperature gradient of over a thousand degrees Celsius between the sintered body’s surface and its interior. This temperature difference induces significant thermal stress during the cooling process, leading to macroscopic surface cracks and even structural failure, which severely limits the engineering feasibility of this technology. To evaluate the surface integrity of lunar in situ sintered bodies and determine the safe processing window for microwave sintering, this study develops a multiphysics computational model that couples electromagnetic, thermal, and stress fields. The results show that when the cooling rate is below 15 ◦C/min, the surface stress remains below the material’s tensile strength threshold, effectively preventing crack formation. However, at a cooling rate of 16 ◦C/min, the surface stress exceeds this threshold, leading to crack initiation. Further analysis reveals that the cooling rate significantly affects the microstructure, with slow cooling maintaining a dense structure, while fast cooling promotes the formation of microcracks, particularly in regions with low Si/Al content. This study provides a reference for the microwave sintering process of lunar regolith and proposes a strategy of controlling the cooling rate below 15 ◦C/min....
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