Applied Magnetic Resonance最新文献_第8页

Estimation of Relaxation Times During Free Evolution from the SECSY Signal of an Electron–Nuclear Spin-Coupled System in a γ-Irradiated Malonic Acid Single Crystal 从γ-辐照丙二酸单晶中电子-核自旋耦合系统的 SECSY 信号估算自由演化过程中的弛豫时间

IF 1 4区物理与天体物理

Applied Magnetic Resonance Pub Date : 2024-04-17 DOI: 10.1007/s00723-024-01653-z

Hamid Reza Salahi, Sushil.K. Misra

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Towards Routine 7Li In Situ Solid-State NMR Studies of Electrochemical Processes in Li|LiPF6|LFP Cells 对 Li|LiPF6|LFP 电池中的电化学过程进行常规 7Li 原位固态 NMR 研究

IF 1.1 4区物理与天体物理

Applied Magnetic Resonance Pub Date : 2024-04-11 DOI: 10.1007/s00723-024-01643-1

Edina Šić, Dominion Fredericks, Oliver Pecher, Sebastian Wegner, Hergen Breitzke, Vickram Singh, Gerd Buntkowsky, Torsten Gutmann

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On the Microstructure and Dynamics of Membranes Formed by Lipid as From Stenotrophomonas maltophilia, a Member of Gut Microbiome: An EPR Study 关于肠道微生物群成员嗜麦芽僵直单胞菌脂质形成的膜的微观结构和动力学：一项 EPR 研究

IF 1.1 4区物理与天体物理

Applied Magnetic Resonance Pub Date : 2024-04-11 DOI: 10.1007/s00723-024-01646-y

G. Vitiello, R. Esposito, I. Speciale, C. De Castro, G. D’Errico

{"title":"On the Microstructure and Dynamics of Membranes Formed by Lipid as From Stenotrophomonas maltophilia, a Member of Gut Microbiome: An EPR Study","authors":"G. Vitiello, R. Esposito, I. Speciale, C. De Castro, G. D’Errico","doi":"10.1007/s00723-024-01646-y","DOIUrl":"10.1007/s00723-024-01646-y","url":null,"abstract":"<div>Lipid As are the main components of the external leaflet of the outer membrane of Gram-negative bacteria. Their molecular structure has evolved to allow the bacteria survival in specific environments. In the present work, we investigate how and to what extent lipid membranes that include in their composition lipid A molecules of a bacterium of the gut microbiota, Stenotrophomonas maltophilia, differ from those formed by the lipid A of the common Gram-negative bacterium Salmonella enterica, which is not specific to the gut and is here used as a reference. Electron Paramagnetic Resonance (EPR) spectroscopy, using spin-labelled lipids as molecular probes, allows the segmental order of the acyl chain and the polarity across the bilayer to be analyzed in detail. Both considered lipid As cause a stiffening of the outermost segments of the acyl chains. This effect increases with increasing the lipid A content and is stronger for the lipid A extracted from Stenotrophomonas maltophilia than for that extracted from Salmonella enterica. At the same time, the local polarity of the bilayer region just below the interface increases. As the inner core of the bilayer is considered, it is found that the lipid A from Salmonella enterica causes a local disorder and a significant reduction of the local polarity, an effect not found for the lipid A from Stenotrophomonas maltophilia. These results are interpreted in terms of the different lengths and distributions of the acyl tails in the two lipid As. It can be concluded that the symmetrically distributed short tails of the lipid A from Stenotrophomonas maltophilia favors a regular packing within the bilayer.</div>","PeriodicalId":469,"journal":{"name":"Applied Magnetic Resonance","volume":"55 12","pages":"1539 - 1551"},"PeriodicalIF":1.1,"publicationDate":"2024-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00723-024-01646-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140578113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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13C MAS NMR Mechanistic Study of Propene Transformation on Silver-Modified ZSM-5 Zeolite in the Presence of Molecular Oxygen 分子氧存在下银改性 ZSM-5 沸石上丙烯转化的 13C MAS NMR 机制研究

IF 1.1 4区物理与天体物理

Applied Magnetic Resonance Pub Date : 2024-04-08 DOI: 10.1007/s00723-024-01652-0

Zoya N. Lashchinskaya, Anton A. Gabrienko, Alexander V. Toktarev, Alexander G. Stepanov

{"title":"13C MAS NMR Mechanistic Study of Propene Transformation on Silver-Modified ZSM-5 Zeolite in the Presence of Molecular Oxygen","authors":"Zoya N. Lashchinskaya, Anton A. Gabrienko, Alexander V. Toktarev, Alexander G. Stepanov","doi":"10.1007/s00723-024-01652-0","DOIUrl":"10.1007/s00723-024-01652-0","url":null,"abstract":"<div>Silver-modified zeolites have demonstrated promising properties for hydrocarbon feedstock valorization and the oxidation of organic compounds. Within the frame of the scientific interest for selective oxidation of light alkenes on metal-modified zeolites, the transformation of propene on Ag/H-ZSM-5 zeolite in the presence of molecular oxygen has been monitored by 13C (CP) MAS NMR spectroscopy at 296–773 K. Silver-allyl intermediate species have been detected by 13C CP/MAS NMR, indicating that Ag+ sites are involved in propene transformation. It is assumed that oxygen and propene compete for the Ag+ adsorption sites, thus prompting propene adsorption on zeolite Brønsted acid sites (BAS) and its further transformation by oligomerization and conjunct polymerization. Among the products of propene oxidation by molecular oxygen, only carbon dioxide has been detected by 13C MAS NMR, implying high activity of Ag/H-ZSM-5 in alkene total oxidation. It is thus inferred that silver-modified zeolite is not a promising catalyst for propene selective oxidation to propene oxide and carbonyl group containing organics.</div>","PeriodicalId":469,"journal":{"name":"Applied Magnetic Resonance","volume":"55 10","pages":"1263 - 1274"},"PeriodicalIF":1.1,"publicationDate":"2024-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140578045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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Spin-Wave Model of Free Induction Decay in Ring Spin Cluster 环状自旋簇自由感应衰变的自旋波模型

IF 1.1 4区物理与天体物理

Applied Magnetic Resonance Pub Date : 2024-03-28 DOI: 10.1007/s00723-024-01650-2

Kirill Tsiberkin, Ekaterina Kovycheva

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EPR Investigation of Gamma-Irradiated Tiopronin 伽马辐照硫普罗宁的 EPR 研究

IF 1.1 4区物理与天体物理

Applied Magnetic Resonance Pub Date : 2024-03-28 DOI: 10.1007/s00723-024-01645-z

Kerem Sütçü, Yunus Emre Osmanoğlu

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Dynamic Viscosity of Blood Serum Determined Using Proton Magnetic Relaxation 利用质子磁弛豫测定血清的动态粘度

IF 1.1 4区物理与天体物理

Applied Magnetic Resonance Pub Date : 2024-03-22 DOI: 10.1007/s00723-024-01644-0

Yulianela Mengana Torres, Manuel Arsenio Lores Guevara, Hugo Ferrales Milán, Lidia Clara Suárez Beyries, Samuel Jorge Rosales Rodríguez, Inocente Rodríguez Reyes, Juan Carlos García Naranjo, Yamirka Alonso Geli

{"title":"Dynamic Viscosity of Blood Serum Determined Using Proton Magnetic Relaxation","authors":"Yulianela Mengana Torres, Manuel Arsenio Lores Guevara, Hugo Ferrales Milán, Lidia Clara Suárez Beyries, Samuel Jorge Rosales Rodríguez, Inocente Rodríguez Reyes, Juan Carlos García Naranjo, Yamirka Alonso Geli","doi":"10.1007/s00723-024-01644-0","DOIUrl":"10.1007/s00723-024-01644-0","url":null,"abstract":"<div>An experimental procedure, based on proton magnetic relaxation, is presented to determine the absolute dynamic viscosity in blood serum (ηS). The blood serum samples were obtained voluntary from whole blood of healthy individuals and patients, and processed by classical methods (centrifugation and decanting). The Carr–Purcell–Meiboom–Gill pulse sequence was employed to determine the transverse proton magnetic relaxation time (T2) in a Tecmag Magnetic Resonance console coupled to a magnet of 0.095 T and the temperature of measurement was 293 K. A theoretical linear behavior of the transverse proton magnetic relaxation rate (1/T2) as a function of ηS was obtained after the consideration of blood serum as an extremely diluted solution of albumin and globulins, and assuming a fast exchange of water molecules between the bound phase and the solvent. A value of ηS = 1.29 ± 0.07 mPa s was obtained in samples belonging to 20 voluntary healthy individuals, which statistically match with the value obtained using the Ostwald viscometer for the same samples (ηS = 1.32 ± 0.04 mPa s, P = 0.104319 > 0.05, α = 0.05). The potential medical utility of the presented proton magnetic resonance procedure was demonstrated in patients with Multiple Myeloma (24) and Sickle Cell Disease (34), in which ηS resulted increased with values of 1.40 ± 0.18 mPa s (P = 0.0137509 < 0.05, α = 0.05) and 1.36 ± 0.10 mPa s (P = 0.00809615 < 0.05, α = 0.05), respectively.</div>","PeriodicalId":469,"journal":{"name":"Applied Magnetic Resonance","volume":"55 5","pages":"527 - 536"},"PeriodicalIF":1.1,"publicationDate":"2024-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140202236","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Motion Corrected DCE-MR Image Reconstruction Using Deep Learning 利用深度学习进行运动校正的 DCE-MR 图像重建

IF 1.1 4区物理与天体物理

Applied Magnetic Resonance Pub Date : 2024-03-11 DOI: 10.1007/s00723-024-01642-2

Taquwa Aslam, Faisal Najeeb, Hassan Shahzad, Madiha Arshad, Hammad Omer

{"title":"Motion Corrected DCE-MR Image Reconstruction Using Deep Learning","authors":"Taquwa Aslam, Faisal Najeeb, Hassan Shahzad, Madiha Arshad, Hammad Omer","doi":"10.1007/s00723-024-01642-2","DOIUrl":"10.1007/s00723-024-01642-2","url":null,"abstract":"<div>Respiratory motion in abdomen generates motion artifacts during Dynamic Contrast Enhanced MRI (DCE-MRI) data acquisition and it is clinically challenging to minimize the motion artifacts. Extraction of self-gated respiratory signal from the acquired k-space data is one of the methods to deal with the respiratory motion artifacts. The literature shows that non-Cartesian trajectories are less sensitive to motion artifacts than Cartesian trajectories. Golden-angle data acquisition in radial trajectory is preferred to extract the self-gated signal that splits the free-breathing data into different respiratory phases; also called motion states or bins. Conventionally, XD-GRASP (eXtra-Dimension golden-angle-radial Sparse Parallel MRI) reconstructs the binned data, but this method has limitations such as it does not preserve noise like texture (MR images have noise like artifacts) and it is a computationally intensive method. This research work proposes the use of a dedicated Convolutional Neural Network (CNN) architecture to remove motion artifacts from the binned (using uniform and adaptive binning) DCE golden-angle-radial liver perfusion data. The results of the proposed method are compared with XD-GRASP reconstruction. The results demonstrate that the proposed method takes significantly less computation time and provides similar quality of the reconstructed images as compared to the XD-GRASP method. Furthermore, receiver coil sensitivity information is required in XD-GRASP to reconstruct the MR image that may be difficult to estimate in some applications, whereas the proposed method does not require any such information.</div>","PeriodicalId":469,"journal":{"name":"Applied Magnetic Resonance","volume":"55 5","pages":"509 - 526"},"PeriodicalIF":1.1,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140124990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Study to Identify and Analyze the Radiosensitivity of 4-Piperidinecarboxylic Acid Using Electron Paramagnetic Resonance Spectroscopy 利用电子顺磁共振波谱鉴别和分析 4-哌啶甲酸辐射敏感性的研究

IF 1.1 4区物理与天体物理

Applied Magnetic Resonance Pub Date : 2024-02-01 DOI: 10.1007/s00723-024-01641-3

Kerem Sütçü

{"title":"A Study to Identify and Analyze the Radiosensitivity of 4-Piperidinecarboxylic Acid Using Electron Paramagnetic Resonance Spectroscopy","authors":"Kerem Sütçü","doi":"10.1007/s00723-024-01641-3","DOIUrl":"10.1007/s00723-024-01641-3","url":null,"abstract":"<div>This study aims to investigate the spectroscopic, dosimetric, and stability properties of free radicals generated within 4-piperidinecarboxylic acid (4PCA) sample due to gamma irradiation within the 2–20 kGy range, utilizing electron paramagnetic resonance (EPR) spectroscopy. To achieve this goal, the EPR signals of the samples were studied in relation to microwave power, ranging from 0.01 to 50 mW, at room temperature. The investigation revealed that γ-irradiation induces the formation of –CH2ĊCH2CH2– (radical I) and –ĊHN– (radical II) radicals within the 4PCA compound. Hyperfine structure constants and g values were also determined for the radicals. The optimal agreement between experimental and computed results within the dose range of 2–20 kGy was achieved using polynomial and linear functions. Experimental measurements were undertaken under varied temperature conditions (123–323 K) to study the dosimetric features of free radicals generated as a consequence of gamma irradiation. Furthermore, an investigation into the time dependency of signal intensity within the irradiated sample was conducted, with the objective of analyzing the long-term stability characteristics of the free radicals present.</div>","PeriodicalId":469,"journal":{"name":"Applied Magnetic Resonance","volume":"55 5","pages":"537 - 549"},"PeriodicalIF":1.1,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139669551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Electron Spin Resonance of Lithium Related Donor Centers in Bulk Si1−xGex Crystals Enriched in 28Si and 72Ge Isotopes 富含 28Si 和 72Ge 同位素的块状 Si1-xGex 晶体中锂相关供体中心的电子自旋共振

IF 1.1 4区物理与天体物理

Applied Magnetic Resonance Pub Date : 2024-01-29 DOI: 10.1007/s00723-023-01640-w

E. A. Kalinina, D. V. Guseinov, A. V. Soukhorukov, A. A. Ezhevskii, D. G. Zverev, F. F. Murzakhanov, N. V. Abrosimov

{"title":"Electron Spin Resonance of Lithium Related Donor Centers in Bulk Si1−xGex Crystals Enriched in 28Si and 72Ge Isotopes","authors":"E. A. Kalinina, D. V. Guseinov, A. V. Soukhorukov, A. A. Ezhevskii, D. G. Zverev, F. F. Murzakhanov, N. V. Abrosimov","doi":"10.1007/s00723-023-01640-w","DOIUrl":"10.1007/s00723-023-01640-w","url":null,"abstract":"<div>The lithium donor centers in Si1–xGex (x = 0.0039–0.05) single crystals enriched in spinless 28Si and 72Ge isotopes (99.998 and 99.984%, respectively) are studied by electron spin resonance at temperatures of T = 3.5–30 K and compared with its behavior in Si crystals. It is shown that lithium center with trigonal ([111]) symmetry has a most stable configuration in bulk Si1–xGex for different values of x < 5 at %. Axial symmetry is explained by the distortion of the lithium central position and their neighboring atoms. The spin relaxation rates were studied in temperature range 4–30 K and it was shown that transverse and longitudinal relaxation consist of two components with rates differ by almost an order of magnitude. Together with Raman processes for 1/T1, a decrease in the exponent below T5 is observed. This behavior is explained by cross-relaxation through states of the distorted configuration of lithium, which arise due to modulation of the crystal field potential by random distribution of Ge atoms.</div>","PeriodicalId":469,"journal":{"name":"Applied Magnetic Resonance","volume":"55 5","pages":"551 - 564"},"PeriodicalIF":1.1,"publicationDate":"2024-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139647841","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0