Purpose: The use of hyperpolarization to enhance the sensitivity of MRI has so far been limited by the decay of the polarization through T1 relaxation. Recently, methods have been proposed that extend the lifetime of the hyperpolarization by storing the spin order in slowly relaxing singlet states.
Methods: With this aim, optimal control theory was applied to create pulses that for near-equivalent spins accomplish transfers in and out of the singlet state with maximum efficiency while ensuring robustness toward variations in the nuclear spin system Hamiltonian (chemical shift, J-couplings, B1 and B0 magnetic field inhomogeneity).
Results: The pulses are designed to accomplish efficient transfer with low B1 amplitude, essential for applications on preclinical and clinical MR scanners.
Conclusion: It is demonstrated that significantly improved efficiency and robustness can be obtained within the limitations of typical MR scanner performance.
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http://dx.doi.org/10.1002/mrm.24733 | DOI Listing |
Chem Rev
January 2025
Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States.
The application of external electric fields to influence chemical reactions at electrode interfaces has attracted considerable interest in recent years. However, the design of electric fields to achieve highly efficient and selective catalytic systems, akin to the optimized fields found at enzyme active sites, remains a significant challenge. Consequently, there has been substantial effort in probing and understanding the interfacial electric fields at electrode/electrolyte interfaces and their effect on adsorbates.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.
Conventional dark-tone paints absorb both visible light and near-infrared (NIR) wavelengths, posing a challenge for light detection and ranging (LiDAR) recognition in autonomous driving. To overcome this issue, various chemical and structural coating materials have been explored to selectively reflect NIR. In this study, we newly propose colloidal photonic crystals with a stopband in the NIR range, fabricated through the spontaneous formation of crystalline arrays of silica particles dispersed in a photocurable resin, as a potential solution.
View Article and Find Full Text PDFJ Perianesth Nurs
January 2025
Department of Otorhinolaryngology, Al Mouwasat University Hospital, Faculty of Medicine, Damascus University, Damascus, Syrian Arab Republic; Faculty of Medicine, Syrian Private University, Damascus, Syrian Arab Republic.
Purpose: The purpose of this meta-analysis is to measure the effectiveness of penehyclidine hydrochloride hydrate (PHC)-an antimuscarinic drug-in preventing postoperative nausea and vomiting (PONV) for different surgeries.
Design: Meta-analysis.
Methods: According to the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines, we conducted an online literature search using PubMed, Web of Science, Scopus, and Embase databases.
ISA Trans
January 2025
Department of Electrical and Computer Engineering, National University of Singapore, 117538, Singapore. Electronic address:
For tolerant containment control of multi-agent systems, considering the challenges in modeling and the impact of actuator faults on system security and reliability, a finite index dynamic event-triggered policy iteration algorithm is proposed. This algorithm only requires input and output data, without relying on system models, and simultaneously considers the faults and energy consumption issues to improve the system reliability and save energy consumption. The conditions are provided to demonstrate the convergence and optimality of the algorithm, including a convergence speed, that is, the number of iterations required for convergence is finite.
View Article and Find Full Text PDFMed Dosim
January 2025
Department of Radiation Oncology, Peking University First Hospital, Beijing, China. Electronic address:
This study presents a patient with a PET-CT detected residual lacrimal sac tumor who was treated with intensity modulated proton therapy (IMPT) and concurrent chemotherapy. The patient a 49-year-old male diagnosed with squamous cell carcinoma of the left lacrimal sac had under-went endoscopic surgery. Postoperative PET-CT implied tumor residual in the left lacrimal sac.
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