The gain of some aperture antennas can be significantly increased by making the antenna near-field phase distribution more uniform, using a phase-transformation structure. A novel dielectric-free phase transforming structure (DF-PTS) is presented in this paper for this purpose, and its ability to correct the aperture phase distribution of a resonant cavity antenna (RCA) over a much wider bandwidth is demonstrated. As opposed to printed multilayered metasurfaces, all the cells in crucial locations of the DF-PTS have a phase response that tracks the phase error of the RCA over a large bandwidth, and in addition have wideband transmission characteristics, resulting in a wideband antenna system. The new DF-PTS, made of three thin metal sheets each containing modified-eight-arm-asterisk-shaped slots, is significantly stronger than the previous DF-PTS, which requires thin and long metal interconnects between metal patches. The third advantage of the new DF-PTS is, all phase transformation cells in it are highly transparent, each with a transmission magnitude greater than - 1 dB at the design frequency, ensuring excellent phase correction with minimal effect on aperture amplitude distribution. With the DF-PTS, RCA gain increases to 20.1 dBi, which is significantly greater than its 10.7 dBi gain without the DF-PTS. The measured 10-dB return loss bandwidth and the 3-dB gain bandwidth of the RCA with DF-PTS are 46% and 12%, respectively.
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http://dx.doi.org/10.1038/s41598-021-93975-2 | DOI Listing |
Inorg Chem
January 2025
Department of Material and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, SE-10691 Stockholm, Sweden.
Zinc oxide (ZnO) is a semiconductor with a wide range of applications, and often the properties are modified by metal-ion doping. The distribution of dopant atoms within the ZnO crystal strongly affects the optical and magnetic properties, making it crucial to comprehend the structure down to the atomic level. Our study reveals the dopant structure and its contents in Eu-doped ZnO nanosponges with up to 20% Eu-O clusters.
View Article and Find Full Text PDFRev Sci Instrum
January 2025
School of Electrical and Electronic Engineering, The University of Manchester, Manchester M13 9PL, United Kingdom.
Carbon fiber reinforced polymers (CFRPs) are widely used in fields such as aviation and aerospace. However, subtle defects can significantly impact the material's service life, making defect detection a critical priority. In this paper, delamination defects in CFRP are detected using line laser infrared thermography, and a defect characterization algorithm that combines differential thermography with a frequency-domain filter is proposed.
View Article and Find Full Text PDFJAMA Oncol
January 2025
Children's Wisconsin, Milwaukee.
Importance: Retrieval strategies for children, adolescents, and young adults with relapsed classic Hodgkin lymphoma (cHL) aim to maintain efficacy while minimizing long-term toxic effects. Children, adolescents, and young adults with low-risk, relapsed cHL may benefit from replacing high-dose chemotherapy and autologous stem cell transplant with less intensive involved-site radiotherapy (ISRT).
Objective: To evaluate a risk-stratified, response-adapted, transplant-free approach for treatment of children, adolescents, and young adults with low-risk relapsed cHL with nivolumab plus brentuximab vedotin (BV) followed by BV plus bendamustine for patients with suboptimal response and ISRT (30.
JAMA Oncol
January 2025
Department of Paediatric Haematology, Oncology and Immunodeficiency, University Hospital Justus-Liebig University Giessen, Giessen, Germany.
Importance: The current standard-of-care salvage therapy in relapsed/refractory classic Hodgkin lymphoma (cHL) includes consolidation high-dose chemotherapy (HDCT)/autologous stem cell transplant (aSCT).
Objective: To investigate whether presalvage risk factors and fludeoxyglucose-18 (FDG) positron emission tomography (PET) response to reinduction chemotherapy can guide escalation or de-escalation between HDCT/aSCT or transplant-free consolidation with radiotherapy to minimize toxic effects while maintaining high cure rates.
Design, Setting, And Participants: EuroNet-PHL-R1 was a nonrandomized clinical trial that enrolled patients younger than 18 years with first relapsed/refractory cHL across 68 sites in 13 countries in Europe between January 2007 and January 2013.
Psychol Serv
January 2025
Center for Health Equity Research and Promotion, Department of Veterans Affairs Pittsburgh Healthcare System.
Chronic insomnia is one of the most common health problems among veterans and can significantly impact health, function, and quality of life. Brief behavioral treatment for insomnia (BBTI), an adaptation of cognitive behavioral therapy for insomnia (CBT-I), was developed to help increase access to care outside of specialty settings. However, training providers alone is rarely sufficient, and implementation strategies are needed for successful uptake, adoption, and sustainable delivery of care.
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