143 research outputs found
Joint design of beam selection and precoding matrices for mmWave MU-MIMO systems relying on lens antenna arrays
No full textWireless transmission relying on lens antenna arrays is becoming more and more attractive for millimeter wave (mmWave) multiple-input multiple-output (MIMO) systems using a limited number of radio frequency (RF) chains due to the lens’ energy-focusing capability. In this paper, we consider the joint design of the beam selection and precoding matrices in order to maximize the sum-rate of a downlink single-sided lens MU-MIMO mmWave system under transmit power constraints. We first formulate the optimization problem into a tractable form using the popular weighted minimum mean squared error(WMMSE) approach. To solve this problem, we then propose an efficient joint beam selection and precoding design algorithm based on the innovative penalty dual decomposition (PDD) method. To reduce the design complexity, we also propose a simplified algorithm by combining the interference-aware beam selection (IA-BS) scheme with the WMMSE approach. Simulation results demonstrate that our proposed algorithms can converge in a few iterations and achieve near-optimal performance when compared to the fully digital precoding scheme, thus enabling them to outperform the competing methods.<br/
Health risks of exposure to wildfire-toxic air: Air pollution impacts
No full textEvaluating the short-term exposure to wildfire-specific fine particulate matter (PM(2.5)) showed greater risks of hospitalization for all major respiratory diseases than non-wildfire PM(2.5). When developing air quality guidelines, it is also important to consider that PM(2.5) from varying sources can have different health effects, which require targeted health and environmental policy approaches.Yiwen Zhang, Rongbin Xu, Wenzhong Huang, Tingting Ye, Pei Yu, Wenhua Yu, Yao Wu, Yanming Liu, Zhengyu Yang, Bo Wen, Ke Ju, Jiangning Song, Michael J. Abramson, Amanda Johnson, Anthony Capon, Bin Jalaludin, Donna Green, Eric Lavigne, Fay H. Johnston, Geoffrey G. Morgan, Luke D. Knibbs, Ying Zhang, Guy Marks, Jane Heyworth, Julie Arblaster, Yue Leon Guo, Lidia Morawska, Micheline S. Z. S. Coelho, Paulo H. N. Saldiva, Patricia Matus, Peng Bi, Simon Hales, Wenbiao Hu, Dung Phung, Yuming Guo, Shanshan L
Joint Transceiver Design for Decoupled Full-Duplex Wireless Powered Communication Networks with Lens Antenna Arrays
No full textApplication of BP neural network to the data classification for power testing of the microwave circuit board
No full textTIM-3 plays a more important role than PD-1 in the functional impairments of cytotoxic T cells of malignant Schwannomas
No full text Cancer immunotherapy using cytotoxic T cells demonstrates dramatic survival benefits in lymphomas, but its efficacy in solid tumors is limited. Here, we investigated the possibility of using cytotoxic T cells to treat malignant Schwannoma, a rare but aggressive nerve sheath tumor, by examining the native T-cell immunity in the host. We found that compared to CD8+ T cells from healthy controls or benign Schwannoma patients, the CD8+ T cells from malignant Schwannoma patients were present at normal frequencies but were substantially enriched with PD-1−TIM-3+ and PD-1+TIM-3+ cells. Compared to the PD-1−TIM-3− CD8+ T cells, the PD-1−TIM-3+ and PD-1+TIM-3+ CD8+ T cells presented significantly lower proliferation capacity, reduced interleukin 2 and interferon gamma expression, and/or dramatically decreased perforin and granzyme B secretion, indicating a whole-spectrum immunosuppression and reduced cytotoxicity. TIM-3 expression alone was associated with lower proliferation and less perforin and granzyme B secretion, whereas PD-1 expression alone was not associated with functional impairments, suggesting that TIM-3 expression was a better marker of exhausted CD8+ T cells. The expression of galectin 9, a TIM-3 ligand, in CD4+ Th cells was significantly elevated in malignant, but not benign, Schwannoma patients and were enriched in CD25+ Treg cells. Both the PD-1−TIM-3+ and PD-1+TIM-3+ CD8+ T cells responded to Treg-mediated and galectin 9–mediated suppression, whereas the PD-1+TIM-3− CD8+ T cells only responded to Treg-mediated suppression. In resected tumors, the malignant Schwannomas had more tumor-infiltrating CD4+ and CD8+ T cells than the benign Schwannomas, but a large fraction of these tumor-infiltrating CD4+ and CD8+ T cells expressed PD-1 and/or TIM-3, which indicated that their antitumor immunity was compromised. Together, our results suggested that PD-1 and TIM-3 blockade might be necessary in developing effective immunotherapeutic strategies in malignant Schwannoma, in which TIM-3 may play a more important role. </jats:p
High-Temperature Oxidation Resistance and Molten Salt Corrosion Study of YSZ, CeYSZ, and YSZ/CeYSZ Thermal Barrier Coatings by Atmospheric Plasma Spraying
No full textFive thermal barrier coatings (TBCs), namely TBC-1 (YSZ), TBC-2 (CeYSZ), TBC-3 (YSZ:CeYSZ = 1:2), TBC-4 (YSZ:CeYSZ = 1:1), and TBC-5 (YSZ:CeYSZ = 2:1), were fabricated using the atmospheric plasma spraying (APS) method. Their oxidation behaviors at 1100 °C and corrosion resistance to molten salts (V2O5 + Na2SO4) at 900 °C were examined. After 100 h of oxidation, the thermally grown oxide layer (TGO) for YSZ primarily contained Cr and Ni oxides with significant internal fractures, presenting a continuous band-like Al2O3. In dual-ceramic configurations, an increase in CeYSZ thickness led to a rise in Al content and reduced Cr and Ni in TGO, with the surface fracture morphing into an internal porosity. Following salt corrosion, YSZ revealed rod-like YVO4 and m-ZrO2 as corrosion products, whereas CeYSZ displayed chain-structured CeO2, CeYO4, and YVO4 combined with m-ZrO2. YSZ coatings underwent notable phase transitions with evident densification, forming a corrosion layer of approximately 10 μm. Conversely, CeYSZ showed a limited phase change, retaining porosity without a distinguishable corrosion layer. As CeYSZ thickness increased from 100 μm to 200 μm in the dual-ceramic structure, salt penetration reduced. Evidently, the dense structure of CeYSZ heightened diffusion resistance against oxygen and corrosive salts, rendering superior oxidation and corrosion resistance over YSZ. By optimizing the thickness ratio between CeYSZ and YSZ, whilst retaining total ceramic layer thickness, the dual-ceramic TBC’s resistance to high-temperature oxidation and corrosion can be enhanced
CD4+Foxp3− type 1 regulatory T cells in glioblastoma multiforme suppress T cell responses through multiple pathways and are regulated by tumor-associated macrophages
No full textJoint design of beam selection and precoding for mmWave MU-MIMO systems with lens antenna array
No full text- …
