A Radio Frequency Quadrupole Cooler (RFQC) prototype was adapted for insertion into a high uniformity magnetic field, with B up to 0.2 T, to improve radial confinement. While the RFQC purpose is to reduce (by gas collisions) the energy spread and emittance of a beam of radioactive nuclei, to finely select ion mass in nuclear physics, the prototype is tested in a setup including a stable ion source, a pepper pot emittance meter, and two Faraday cups; this makes a precise characterization of the RFQC feasible. The ion extraction was studied in detail by simulations, both to match it to the emittance meter granularity and to verify the effect of the typical nonuniformity of the longitudinal electric field E inside the RFQC; an average motion description (including friction force from gas collisions) was used, introducing the ballistic and diffusive regimes. With a preliminary optimization of the electrode shape, buffer gas pressure p, and radio frequency voltage, the ion beam can be extracted with a significant cooling margin.
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http://dx.doi.org/10.1063/1.5128225 | DOI Listing |
Sci Bull (Beijing)
January 2025
School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, China; Center for High Energy Physics, Peking University, Beijing 100871, China; Key Laboratory of Particle Acceleration Physics and Technology, Chinese Academy of Sciences, Beijing 100049, China. Electronic address:
Dark photons, as a minimal extension of the Standard Model through an additional Abelian gauge group, may propagate relativistically across the galaxy, originating from dark matter decay or annihilation, thereby contributing to a galactic dark photon background. The generation of dark photons typically favors certain polarization modes, which are dependent on the interactions between dark matter and dark photons. We introduce a framework in which a resonant cavity is utilized to detect and differentiate these polarizations, leveraging the daily variation in expected signals due to the anisotropic distribution of dark photons and the rotation of the Earth.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Sciences, 100 Let Vladivostoku Prosp., 159, 690022 Vladivostok, Russian Federation.
The structure and anti-SARS-CoV-2 activity of sulfated polysaccharides (Mzpt) obtained in high yield (60 %) from tetrasporophytes of Mazzaella parksii were studied. Stepwise fractionation with KCl showed that Mzpt consisted of eight (MzptF1-MzptF8) carrageenans fractions, differing in structure and molecular weight. The yield of non-gelling MzptF8 was 58.
View Article and Find Full Text PDFBMC Cancer
January 2025
Unité de Sénologie, Centre Jean PERRIN, Clermont-Ferrand, France.
Background: Most breast cancers are detected at an early stage in which case conservative surgery is indicated. An accurate preoperative localization technique is essential for conservative surgery of non-palpable breast lesions. Currently, the gold standard technique is wire localization (WL).
View Article and Find Full Text PDFBMC Cancer
January 2025
Department of Physical Medicine and Rehabilitation, Soonchunhyang University Hospital Seoul, Soonchunhyang University College of Medicine, 59, Daesagwan-ro, Yongsan-gu, Seoul, 04401, Republic of Korea.
Background: As the roles of chemotherapy (Chemo) and radiation therapy (Radio) in the definitive treatment of breast cancer have expanded, a broader understanding of the factors associated with breast cancer-related lymphedema (BCRL) has become increasingly essential. Therefore, we investigated the association between multimodality treatment and the risk of BCRL.
Methods: In this retrospective study conducted using National Health Insurance data and the Korea National Cancer Incidence Database (2006-2017), 114,638 participants who underwent Surgery (Surg) or Chemo within 6 months after breast cancer diagnosis were enrolled, and the effect of multimodality treatment on the risk of BCRL was analyzed using the Cox proportional-hazards model.
Microsyst Nanoeng
January 2025
Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, PA, 19104, USA.
Bulk Acoustic Wave (BAW) filters find applications in radio frequency (RF) communication systems for Wi-Fi, 3G, 4G, and 5G networks. In the beyond-5G (potential 6G) era, high-frequency bands (>8 GHz) are expected to require resonators with high-quality factor (Q) and electromechanical coupling ( ) to form filters with low insertion loss and high selectivity. However, both the Q and of resonator devices formed in traditional uniform polarization piezoelectric films of aluminum nitride (AlN) and aluminum scandium nitride (AlScN) decrease when scaled beyond 8 GHz.
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