Magnetic Resonance Letters最新文献

{"title":"Unraveling boron-organic template interactions in [B, Al]-ZSM-5 zeolite using solid-state NMR spectroscopy","authors":"Yongxiang Wang ,&nbsp;Shuangqin Zeng ,&nbsp;Pengfei Wang ,&nbsp;Mingji Zheng ,&nbsp;Weidong Huang ,&nbsp;Yueying Chu ,&nbsp;Ningdong Feng ,&nbsp;Guodong Qi ,&nbsp;Qiang Wang ,&nbsp;Jun Xu ,&nbsp;Feng Deng","doi":"10.1016/j.mrl.2024.200174","DOIUrl":"10.1016/j.mrl.2024.200174","url":null,"abstract":"<div><div>Organic structure directing agents (OSDAs), such as tetrapropylammonium (TPA) cations, serve as crucial templates for the formation of zeolite frameworks. These organic molecules interact with inorganic species, guiding the assembly of the zeolite structure. In this study, we investigate the complex interplay between boron species and TPA cations during the crystallization of [B, Al]-ZSM-5 zeolites. Two-dimensional(2D) ¹¹B-{¹H} cross-polarization heteronuclear correlation (CP-HECTOR) NMR experiments elucidate distinct interactions between two boron species, B(IV)-1 and B(IV)-2, and the propyl chain of the TPAs. Amorphous B(IV)-1 species exhibit a strong preference for proximity to the nitrogen cation center of the OSDAs, while framework B(IV)-2 species engage with components situated at greater distances from the cation center. Moreover, ¹³C-{¹¹B} symmetry-based resonance-echo saturation-pulse double-resonance (<em>S</em>-RESPDOR) experiments revealed that framework boron species preferentially occupy the straight channels of the MFI structure, as evidenced by their interaction with specific methyl groups on the TPA molecules. This observation provides valuable insights into the crystallization mechanism of boron-based zeolites, suggesting that the conformation and orientation of the OSDA molecules play a critical role in determining the location of boron atoms within the zeolite framework.</div></div>","PeriodicalId":93594,"journal":{"name":"Magnetic Resonance Letters","volume":"5 2","pages":"Article 200174"},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144213457","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Raising microwave power drives solid effect DNP enhancements beyond 500 at 9.4 T","authors":"Hong Shi ,&nbsp;Qingjia Bao ,&nbsp;Xin Zhou ,&nbsp;Maili Liu ,&nbsp;Chaoyang Liu","doi":"10.1016/j.mrl.2025.200192","DOIUrl":"10.1016/j.mrl.2025.200192","url":null,"abstract":"","PeriodicalId":93594,"journal":{"name":"Magnetic Resonance Letters","volume":"5 2","pages":"Article 200192"},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144213458","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An amphiphilic peptide with unnatural amino acids as an alignment medium for RDC measurements","authors":"Yishen Wang ,&nbsp;Haizhi Yin ,&nbsp;Yanling Yang ,&nbsp;Zheng-Hui Li ,&nbsp;Gao-Wei Li ,&nbsp;Xinxiang Lei","doi":"10.1016/j.mrl.2024.200171","DOIUrl":"10.1016/j.mrl.2024.200171","url":null,"abstract":"<div><div>The multiple oligopeptides have been regarded as promising alignment media due to their structural diverseness and tendency for self-assembly in solution. Herein, an assembled amphiphilic peptide alignment medium, i.e., C₁₅–CONH-Phg-Phg-IIIKK-CONH₂ with unnatural amino acids for the determination of anisotropic parameters of NMR is introduced. The amphiphilic peptide can be self-assembled at low concentrations in DMSO and is stable and highly homogeneous. The NMR spectrum collected with the addition of the medium had fewer background signals. The utility of the acquired RDC data is demonstrated to determine relative configuration of three natural products, Helminthosporic acid, Estrone, and α-Santonin.</div></div>","PeriodicalId":93594,"journal":{"name":"Magnetic Resonance Letters","volume":"5 2","pages":"Article 200171"},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144213454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL-IQ) for evaluation of early bone mass changes in ageing osteoporosis patients","authors":"Yonggui Yang ,&nbsp;Fang Chen ,&nbsp;Xiufen Wu ,&nbsp;Xinyu Xu ,&nbsp;Pu-Yeh Wu","doi":"10.1016/j.mrl.2024.200157","DOIUrl":"10.1016/j.mrl.2024.200157","url":null,"abstract":"<div><div>This study explored the application value of iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL-IQ) technology in the early diagnosis of ageing osteoporosis (OP). 172 participants were enrolled and underwent magnetic resonance imaging (MRI) examinations on a 3.0T scanner. 100 cases were included in the normal group (50 males and 50 females; mean age: 45 years; age range: 20–84 years). 33 cases were included in the osteopenia group (17 males and 16 females; mean age: 55 years; age range: 43–83 years). 39 cases were included in the OP group (19 males and 20 females; mean age: 58 years; age range: 48–82 years). Conventional T₁WI and T₂WI were first obtained, followed by 3D-IDEAL-IQ-acquisition. Fat fraction (<em>FF</em>) and apparent transverse relaxation rate (<em>R</em>₂^∗) results were automatically calculated from IDEAL-IQ-images on the console. Based on T₁W and T₂W-images, 300 ROIs for each participant were manually delineated in L₁-L₅ vertebral bodies of five middle slices. In each age group of all normal subjects, each parameter was significantly correlated with gender. In male participants from the normal, osteopenia, and OP groups, statistical analysis revealed <em>F</em> values of 11319.292 and 180.130 for comparisons involving <em>FF</em> and <em>R</em>₂^∗ values, respectively (all <em>p</em> &lt; 0.0001). The sensitivity and specificity of <em>FF</em> values were 0.906 and 0.950, 0.994 and 0.997, 0.865 and 0.820, respectively. For <em>R</em>₂^∗, they were 0.665 and 0.616, 0.563 and 0.519, 0.571 and 0.368, respectively. In female participants from the normal, osteopenia, and OP-groups, statistical analysis revealed <em>F</em> values of 12461.658 and 548.274 for comparisons involving <em>FF</em> and <em>R</em>₂^∗ values, respectively (all <em>p</em> &lt; 0.0001). The sensitivity and specificity of <em>FF</em> values were 0.985 and 0.991, 0.996 and 0.996, 0.581 and 0.678, respectively. For <em>R</em>₂^∗, they were 0.698 and 0.730, 0.603 and 0.665, 0.622 and 0.525, respectively. Significant differences were indicated in the quantitative values among the three groups. <em>FF</em> value had good performance, while <em>R</em>₂^∗ value had poor performance in discriminating osteopenia and OP-groups. Overall, the IDEAL-IQ technique offers specific reference indices that enable noninvasive and quantitative assessment of lumbar vertebrae bone metabolism, thereby providing diagnostic information for OP.</div></div>","PeriodicalId":93594,"journal":{"name":"Magnetic Resonance Letters","volume":"5 2","pages":"Article 200157"},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144213452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural and functional neural correlates of sensorimotor deficits in progression of hepatic encephalopathy","authors":"Guanchen Sha ,&nbsp;Yuefan Liu ,&nbsp;Yutong Cao ,&nbsp;Qi Zhang ,&nbsp;Yining Zhang ,&nbsp;Yuanyuan Chen ,&nbsp;Qiuyun Fan ,&nbsp;Yue Cheng","doi":"10.1016/j.mrl.2024.200156","DOIUrl":"10.1016/j.mrl.2024.200156","url":null,"abstract":"<div><div>Hepatic encephalopathy (HE) is a neurological condition that occurs as a complication of liver dysfunction that involves sensorimotor symptoms in addition to cognitive and behavioral changes, particularly in cases of severe liver disease or cirrhosis. Previous studies have reported spatially distributed structural and functional abnormalities related to HE, but the exact relationship between the structural and functional alterations with respect to disease progression remains unclear. In this study, we performed surface-based cortical thickness comparisons and functional connectivity (FC) analyses between three cross-sectional groups: healthy controls (HC, <em>N</em> = 51), patients with minimal hepatic encephalopathy (MHE, <em>N</em> = 50), patients with overt hepatic encephalopathy (OHE, <em>N</em> = 51). In addition to the distributed cortical thinning that is extensively thought to be associated with cognitive decline in HE, we found significant cortical thickening in the left parahippocampal gyrus cortex in the OHE group (<em>p</em> &lt; 0.001, <em>p</em> = 0.009) as compared to the HC and MHE group respectively, which is further corroborated by the significant correlation between the cortical thickness and digit symbol test (DST) scores. Furthermore, the decreased FC between the right postcentral gyrus and several sensory regions (bilateral somatosensory and visual cortices) was found to be significant in MHE patients as compared to the HC group. Our results revealed cross-sectional structural and functional variations concerning disease progression across different subsystems (e.g., visual, motor and sensory), providing evidence that can potentially explain the mechanisms underlying the sensorimotor and cognitive deficits related to HE.</div></div>","PeriodicalId":93594,"journal":{"name":"Magnetic Resonance Letters","volume":"5 2","pages":"Article 200156"},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144213451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Applications of nuclear magnetic resonance in exploring structure and energy storage mechanism of supercapacitors","authors":"Yang Du,&nbsp;Hua Huo","doi":"10.1016/j.mrl.2024.200172","DOIUrl":"10.1016/j.mrl.2024.200172","url":null,"abstract":"<div><div>Supercapacitors, comprising electrical double-layer capacitors (EDLCs) and pseudocapacitors, are widely acknowledged as high-power energy storage devices. However, their local structures and fundamental mechanisms remain poorly understood, and suitable experimental techniques for investigation are also lacking. Recently, nuclear magnetic resonance (NMR) has emerged as a powerful tool for addressing these fundamental issues with high local sensitivity and non-invasiveness. In this paper, we first review the limitations of existing characterization methods and highlight the advantages of NMR in investigating mechanisms of supercapacitors. Subsequently, we introduce the basic principle of ring current effect, NMR-active nuclei, and various NMR techniques employed in exploring energy storage mechanisms including cross polarization (CP) magic angle spinning (MAS) NMR, multiple-quantum (MQ) MAS, two-dimensional exchange spectroscopy (2D-EXSY) NMR, magnetic resonance imaging (MRI) and pulsed-field gradient (PFG) NMR. Based on this, recent progress in investigating energy storage mechanisms in EDLCs and pseudocapacitors through various NMR techniques is discussed. Finally, an outlook on future directions for NMR research in supercapacitors is offered.</div></div>","PeriodicalId":93594,"journal":{"name":"Magnetic Resonance Letters","volume":"5 2","pages":"Article 200172"},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144213455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"OFC: Outside Front Cover","authors":"","doi":"10.1016/S2772-5162(25)00034-8","DOIUrl":"10.1016/S2772-5162(25)00034-8","url":null,"abstract":"","PeriodicalId":93594,"journal":{"name":"Magnetic Resonance Letters","volume":"5 2","pages":"Article 200209"},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144213450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurement of protein non-covalent interactions in buffer and cells","authors":"Jingwen Li ,&nbsp;Xiangfei Song ,&nbsp;Lishan Yao","doi":"10.1016/j.mrl.2024.200173","DOIUrl":"10.1016/j.mrl.2024.200173","url":null,"abstract":"<div><div>Nuclear magnetic resonance (NMR) serves as a powerful tool for studying both the structure and dynamics of proteins. The NOE method, alongside residual dipolar; coupling, paramagnetic effects, <em>J</em>-coupling, and other related techniques, has reached a level of maturity that allows for the determination of protein structures. Furthermore, NMR relaxation methods prove to be highly effective in characterizing protein dynamics across various timescales. The properties of protein systems are dictated by intra- and intermolecular interactions among atoms, which involve covalent bonds, hydrogen bonds (H-bonds), electrostatic interactions, and van der Waals forces. Multiple NMR approaches have been developed to measure noncovalent interactions, and this paper offers a concise overview of noncovalent interaction measurements using NMR, with a specific emphasis on the advancements accomplished in our laboratory.</div></div>","PeriodicalId":93594,"journal":{"name":"Magnetic Resonance Letters","volume":"5 2","pages":"Article 200173"},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144213456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A hybrid denoising method for low-field nuclear magnetic resonance data","authors":"Yongjie Zhao ,&nbsp;Ranhong Xie ,&nbsp;Ke Huang ,&nbsp;Huan Su ,&nbsp;Jiangfeng Guo","doi":"10.1016/j.mrl.2024.200167","DOIUrl":"10.1016/j.mrl.2024.200167","url":null,"abstract":"<div><div>Low-field nuclear magnetic resonance (NMR) has broad application prospects in the exploration and development of unconventional oil and gas reservoirs. However, NMR instruments tend to acquire echo signals with relatively low signal-to-noise ratio (SNR), resulting in poor accuracy of <em>T</em>₂ spectrum inversion. It is crucial to preprocess the low SNR data with denoising methods before inversion. In this paper, a hybrid NMR data denoising method combining empirical mode decomposition-singular value decomposition (EMD-SVD) was proposed. Firstly, the echo data were decomposed with the EMD method to low- and high-frequency intrinsic mode function (IMF) components as well as a residual. Next, the SVD method was employed for the high-frequency IMF components denoising. Finally, the low-frequency IMF components, the denoised high-frequency IMF components, and the residual are summed to form the denoised signal. To validate the effectiveness and feasibility of the EMD-SVD method, numerical simulations, experimental data, and NMR log data processing were conducted. The results indicate that the inverted NMR spectra with the EMD-SVD denoising method exhibit higher quality compared to the EMD method and the SVD method.</div></div>","PeriodicalId":93594,"journal":{"name":"Magnetic Resonance Letters","volume":"5 2","pages":"Article 200167"},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144213453","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Artificial intelligence goes from predicting structure to predicting stability","authors":"Gary J. Pielak ,&nbsp;Conggang Li ,&nbsp;Maili Liu","doi":"10.1016/j.mrl.2025.200176","DOIUrl":"10.1016/j.mrl.2025.200176","url":null,"abstract":"","PeriodicalId":93594,"journal":{"name":"Magnetic Resonance Letters","volume":"5 1","pages":"Article 200176"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143609286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}