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Objectives: The increasing number of elderly patients with severe aortic valve stenosis undergoing transcatheter aortic valve replacement (TAVR) has prompted concerns regarding their clinical outcomes compared with the younger population. This study evaluated the outcomes of TAVR on the basis of age group (

Bismaleimide (BMI) resins are high-performance thermosets that are primarily used in aerospace because of their exceptional heat resistance and physical properties. However, their growing demand has led to significant environmentally unfriendly waste. To address this, our research proposes a reprocessable BMI system using a newly synthesized BMI vitrimer (BMIV) with functional groups that form covalent adaptable networks (CANs). To enhance the properties, a symmetrical BMI with two ester groups introduced into the rigid rod molecule was designed as a CAN component. After confirming the structure using various spectroscopic techniques, BMIV was coupled with aromatic diamines via an additional aza-Michael reaction to obtain the cured resins. Subsequently, the mechanical properties and reprocessing behavior of the thermally stable and optimized thermosetting material with the best performance were evaluated, and the evidence, mechanism, and activation energy of the topology rearrangement are reported in detail.

Transfer of natural radionuclides from soil to water spinach (Ipomoea aquatica Forssk) in Hanoi, Vietnam have been investigated using a low background gamma spectrometer with an HPGe detector (Model-GC5019). Twenty pairs of soil and water spinach samples in two environmental conditions, i.e., flooded and unflooded, were collected for measuring the activity concentrations and determining the soil-to-plant transfer factors (TFs) of natural radionuclides. For water spinach, stems and leaves were collected as the main parts for human consumption and livestock food. The TF of 40 K is within the range of 0.32-2.49, which is greater than that of 228 Ra (0.01-0.17) and 226 Ra (0.01-0.13). The geometric means (geometric standard deviations) of the TFs are 1.17(1.89), 0.05(2.41) and 0.04(1.88) for flooded sites, and 0.89(1.73), 0.03(2.12) and 0.03(1.82) for unflooded sites, respectively. Comparing between the flooded and unflooded sites, the TFs are all greater at the flooded sites., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

An intercomparison of neutron personal dose equivalent measured by the Harshaw thermoluminescence neutron dosimeters (TLDs) between the National Institute of Metrology of China (NIM) and the Institute for Nuclear Science and Technology of Vietnam (INST) was performed. Three sets of TLDs (each set consisting of five TLDs) were prepared for each laboratory. Each set was then irradiated to the corresponding same nominal standard value of neutron personal dose equivalent, H p (10) n-std i , of 1.0, 2.0, and 3.0 mSv, respectively at these two laboratories. The irradiated TLDs were then read-out at the INST using the Harshaw 4500-type TLD reader to obtain neutron personal dose equivalents at the NIM, H p (10) n-NIM i and at the INST, H p (10) n-INST i , which are corresponding to different values of H p (10) n-std i . The TLDs' responses to different scattered components of neutrons in these two fields are also discussed. Comparisons between the corresponding pair values of H p (10) n-NIM i and H p (10) n-INST i show good agreements within 10% with the standard uncertainty of 12.5% (k = 1). The measured values of H p (10) n-NIM i and H p (10) n-INST i are satisfied the Trumpet curve criteria. This implies that the TLDs can be used for safety assessment of occupational neutron personal dose equivalents. This intercomparison result also confirms the capabilities of these two laboratories (i.e., NIM, INST) on deliveries of neutron personal dose equivalent standard values for calibrations., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)