A perturbation method deals with dipolar coupling spins in solids is presented. As example of application the method, the multiple-quantum coherence dynamics in clusters of a linear chain of four nuclear spins and a ring of six spins coupled by dipole-dipole interaction are considered. The calculated 0Q and 2Q intensities in a linear chain of four nuclear spins and 6Q intensity in a ring of six spins vs. the duration of the preparation period agree well with the exact solutions (for linear chain of four nuclear spins) and simulation data (for linear chain of four nuclear spins and a ring of six spin).
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.ssnmr.2005.04.002 | DOI Listing |
J Chem Inf Model
January 2025
Key Laboratory for Photonic and Electronic Bandgap Materials, Ministry of Education, College of Chemistry and Chemical Engineering, Harbin Normal University, Harbin 150025, China.
Tryptophan participates in important life activities and is involved in various metabolic processes. The indole and aromatic binuclear ring structure in tryptophan can engage in diverse interactions, including π-π, π-alkyl, hydrogen bonding, cation-π, and CH-π interactions with other side chains and protein targets. These interactions offer extensive opportunities for drug development.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Freie Universität Berlin: Freie Universitat Berlin, Institut für Chemie und Biochemie, GERMANY.
Herein, we present the first easy-to-access synthesis of the perfluorotrityl cation (15F+) with commercial GaCl3 and the further functionalization of the para-fluorine atoms of 15F+ via halodefluorination using trimethylsilyl halides TMSX (X = Cl, Br). This gives access to equally reactive perhalogenated trityl derivatives (p-3Cl12F+ and p-3Br12F+), which can be handled at room temperature. The impact of the para-exchange on the electronic structure is determined by NMR and UV-Vis spectroscopy.
View Article and Find Full Text PDFJ Bras Pneumol
January 2025
. Departamento de Biologia Geral, Universidade Federal Fluminense, Niterói (RJ) Brasil.
Objective: Silicosis is a pneumoconiosis characterized by fibrosis of the lung parenchyma caused by the inhalation of silica particles. Silica dust inhalation is associated with inflammation and induction of oxidative stress in the lungs. This oxidative stress affects telomeres, which are short tandem DNA repeats that cap the end of linear chromosomes.
View Article and Find Full Text PDFAppl Biochem Biotechnol
January 2025
Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka, 565-0871, Japan.
Cyanobacteria are advantageous hosts for industrial applications toward achieving sustainable society due to their unique and superior properties such as atmospheric CO fixation via photosynthesis. However, cyanobacterial productivities tend to be weak compared to heterotrophic microbes. To enhance them, it is necessary to understand the fundamental metabolic mechanisms unique to cyanobacteria.
View Article and Find Full Text PDFDiscov Oncol
January 2025
Department of Orthopedics, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, 200072, China.
Sarcoma (SARC), a diverse group of stromal tumors arising from mesenchymal tissues, is often associated with a poor prognosis. Emerging evidence indicates that senescent cells within the tumor microenvironment (TME) significantly contribute to cancer progression and metastasis. Although the influence of senescence on SARC has been partially acknowledged, it has yet to be fully elucidated.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!