We describe a magic-angle spinning NMR experiment for (1)H-(1)H homonuclear dipole-dipole coupling estimations in organic solids. The methodology involves reintroducing dipolar interactions with rotor-synchronized homonuclear decoupling pulse sequences. Frequency-selective DANTE pulses are used to isolate a specific spin pair from a natural isotopic abundance sample. The coupling of interest, between the selected spin pair, may be extracted by a non linear least-squares fit of the experimentally observed modulation of the signal intensity to an exact analytical formula. The experiment is demonstrated on natural isotopic abundance glycine and alanine powder samples.
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Nat Chem
January 2025
SAMS Research Group, Université de Strasbourg, CNRS, Institut Charles Sadron UPR 22, Strasbourg, France.
Molecular spin qubits have the advantages of synthetic flexibility and amenability to be tailored to specific applications. Among them, chromophore-radical systems have emerged as appealing qubit candidates. These systems can be initiated by light to form triplet-radical pairs that can result in the formation of quartet states by spin mixing.
View Article and Find Full Text PDFSci Rep
January 2025
Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran.
Observing quantum mechanical characteristics in biological processes is a surprising and important discovery. One example, which is gaining more experimental evidence and practical applications, is the effect of weak magnetic fields with extremely low frequencies on cells, especially cancerous ones. In this study, we use a mathematical model of ROS dynamics in cancer cells to show how ROS oscillatory patterns can act as a resonator to amplify the small effects of the magnetic fields on the radical pair dynamics in mitochondrial Complex III.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Department of Chemical and Biological Engineering, Sookmyung Women's University, Seoul 04310, Korea.
Advancements in printing techniques are essential for fabricating next-generation displays. Lead halide perovskites demonstrate great potential as light emitters of solution-processed light-emitting diodes (LEDs). In particular, the perovskite/polymer composite emitters exhibit exceptional luminescent characteristics, mechanical flexibility, and environmental stability due to the improved film morphologies and defect passivation achieved through the introduction of polymer additives.
View Article and Find Full Text PDFNat Mater
January 2025
School of Physics, Zhejiang University, Hangzhou, China.
In ordered magnets, the elementary excitations are spin waves (magnons), which obey Bose-Einstein statistics. Similarly to Cooper pairs in superconductors, magnons can be paired into bound states under attractive interactions. The Zeeman coupling to a magnetic field is able to tune the particle density through a quantum critical point, beyond which a 'hidden order' is predicted to exist.
View Article and Find Full Text PDFInvest Radiol
January 2025
From the Department of Radiology, Stanford University, Stanford, CA (K.W., M.J.M., A.M.L., A.B.S., A.J.H., D.B.E., R.L.B.); Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA (K.W.); GE HealthCare, Houston, TX (X.W.); GE HealthCare, Boston, MA (A.G.); and GE HealthCare, Menlo Park, CA (P.L.).
Objectives: Pancreatic diffusion-weighted imaging (DWI) has numerous clinical applications, but conventional single-shot methods suffer from off resonance-induced artifacts like distortion and blurring while cardiovascular motion-induced phase inconsistency leads to quantitative errors and signal loss, limiting its utility. Multishot DWI (msDWI) offers reduced image distortion and blurring relative to single-shot methods but increases sensitivity to motion artifacts. Motion-compensated diffusion-encoding gradients (MCGs) reduce motion artifacts and could improve motion robustness of msDWI but come with the cost of extended echo time, further reducing signal.
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