Prompt-gamma profile was measured at WPE-Essen using 160 MeV protons impinging a movable PMMA target. A single collimated detector was used with time-of-flight (TOF) to reduce the background due to neutrons. The target entrance rise and the Bragg peak falloff retrieval precision was determined as a function of incident proton number by a fitting procedure using independent data sets. Assuming improved sensitivity of this camera design by using a greater number of detectors, retrieval precisions of 1 to 2 mm (rms) are expected for a clinical pencil beam. TOF improves the contrast-to-noise ratio and the performance of the method significantly.
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http://dx.doi.org/10.1088/0031-9155/59/5/1327 | DOI Listing |
Sensors (Basel)
January 2025
Department of Biomedical Engineering, Yonsei University, Wonju 26493, Republic of Korea.
This study presents the fabrication of a sustainable flexible humidity sensor utilizing chitosan derived from mealworm biomass as the primary sensing material. The chitosan-based humidity sensor was fabricated by casting chitosan and polyvinyl alcohol (PVA) films with interdigitated copper electrodes, forming a laminate composite suitable for real-time, resistive-type humidity detection. Comprehensive characterization of the chitosan film was performed using Fourier-transform infrared (FTIR) spectroscopy, contact angle measurements, and tensile testing, which confirmed its chemical structure, wettability, and mechanical stability.
View Article and Find Full Text PDFInt J Mol Sci
January 2025
College of Pharmacy, Qiqihar Medical University, Qiqihar 161006, China.
A novel fluorescent probe, Bibc-DNBS, based on the combination of the PET (photoinduced electron transfer) and ESIPT (excited-state intramolecular proton transfer) mechanisms, was designed and synthesized. Bibc-DNBS exhibited a Stokes shift of 172 nm in the fluorescence detection field. In addition, the probe exhibited good performance in key parameters in bioassays such as sensitivity, specificity, and response time.
View Article and Find Full Text PDFZhonghua Kou Qiang Yi Xue Za Zhi
January 2025
Department of Stomatology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology & School of Stomatology, Tongji Medical College, Huazhong University of Science and Technology & Hubei Province Key Laboratory of Oral and Maxillofacial Development and Regeneration, Wuhan 430022, China.
To investigate the effects of artificial light at night on the growth of mandibles in mice and its regulatory mechanisms. A mouse model of artificial light at night (night light pollution group) and normal lighting (normal light group) was established by controlling light exposure time, with 4 mice in each group. Micro-CT was employed to analyze the differences in bone quantities of the mandibles between the two groups.
View Article and Find Full Text PDFDev Dyn
January 2025
Department of Medicine, Michigan State University College of Human Medicine, East Lansing, Michigan, USA.
Disruption of extracellular pH and proton-sensing can profoundly impact cellular and protein functions, leading to developmental defects. To visualize changes in extracellular pH in the developing embryo, we generated a zebrafish transgenic line that ubiquitously expresses the ratiometric pH-sensitive fluorescent protein pHluorin2, tethered to the extracellular face of the plasma membrane using a glycosylphosphatidylinositol (GPI) anchor. Monitoring of pHluorin2 with ratiometric fluorescence revealed dynamic and discrete domains of extracellular acidification over the first 72 h of embryonic development.
View Article and Find Full Text PDFBackground: In proton radiotherapy, the steep dose deposition profile near the end of the proton's track, the Bragg peak, ensures a more conformed deposition of dose to the tumor region when compared with conventional radiotherapy while reducing the probability of normal tissue complications. However, uncertainties, as in the proton range, patient geometry, and positioning pose challenges to the precise and secure delivery of the treatment plan (TP). In vivo range determination and dose distribution are pivotal for mitigation of uncertainties, opening the possibility to reduce uncertainty margins and for adaptation of the TP.
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