Effects of gradient high-field static magnetic fields on diabetic mice

Although 9.4 T magnetic resonance imaging(MRI) has been tested in healthy volunteers,its safety in diabetic patients is unclear.Furthermore,the effects of high static magnetic fields(SMFs),especially gradient vs.uniform fields,have not been investigated in diabetics.Here,we investigated the consequences of exposure to 1.0-9.4 T high SMFs of different gradients(>10 T/m vs.0-10 T/m)on type 1 diabetic(T1D) and type 2 diabetic(T2D) mice.We found that 14 h of prolonged treatment of gradient(as high as 55.5 T/m) high SMFs(1.0-8.6 T) had negative effects on T1D and T2D mice,including spleen,hepatic,and renal tissue impairment and elevated glycosylated serum protein,blood glucose,inflammation,and anxiety,while 9.4 T quasi-uniform SMFs at 0-10 T/m did not induce the same effects.In regular T1D mice(blood glucose>16.7 mmol/L),the>10 T/m gradient high SMFs increased malondialdehyde(P<0.01) and decreased superoxide dismutase(P<0.05).However,in the severe T1D mice(blood glucose≥30.0 mmol/L),the>10 T/m gradient high SMFs significantly increased tissue damage and reduced survival rate.In vitro cellular studies showed that gradient high SMFs increased cellular reactive oxygen species and apoptosis and reduced MS-1 cell number and proliferation.Therefore,this study showed that prolonged exposure to high-field(1.0-8.6 T)>10 T/m gradient SMFs(35-1 380 times higher than that of current clinical MRI)can have negative effects on diabetic mice,especially mice with severe T1D,whereas 9.4 T high SMFs at 0-10T/m did not produce the same effects,providing important information for the future development and clinical application of SMFs,especially high-field MRI.

Ultra-high-field magnetic resonance:Why and when?

This paper briefly summarizes the development of magnetic resonance imaging and spectroscopy in medicine.Aspects of magnetic resonancephysics and-technology relevant at ultra-high magnetic fields as well as current limitations are highlighted.Based on the first promising studies,potential clinical applications at 7 Tesla are suggested.Other aims are to stimulate awareness of the potential of ultra-high field magnetic resonance and to stimulate active participation in much needed basic or clinical research at 7 Tesla or higher.

Multi-objective optimization of gradient coil for benchtop magnetic resonance imaging system with high-resolution

Significant high magnetic gradient field strength is essential to obtaining high-resolution images in a benchtop mag- netic resonance imaging （BT-MRI） system with permanent magnet. Extending minimum wire spacing and maximum wire width of gradient coils is one of the key solutions to minimize the maximum current density so as to reduce the local heating and generate higher magnetic field gradient strength. However, maximum current density is hard to optimize together with field linearity, stored magnetic energy, and power dissipation by the traditional target field method. In this paper, a new multi-objective method is proposed to optimize the maximum current density, field linearity, stored magnetic energy, and power dissipation in MRI gradient coils. The simulation and experimental results show that the minimum wire spacings are improved by 159% and 62% for the transverse and longitudinal gradient coil respectively. The maximum wire width increases from 0.5 mm to 1.5 mm. Maximum gradient field strengths of 157 mT/m and 405 mT/m for transverse and lon- gitudinal coil are achieved, respectively. The experimental results in BT-MRI instrument demonstrate that the MRI images with in-plane resolution of 50 ~tm can be obtained by using the designed coils.

Three-dimensional time-of-flight magnetic resonance angiography combined with high resolution T2-weighted imaging in preoperative evaluation of microvascular decompression

BACKGROUND Neurovascular compression(NVC) is the main cause of primary trigeminal neuralgia(TN) and hemifacial spasm(HFS). Microvascular decompression(MVD) is an effective surgical method for the treatment of TN and HFS caused by NVC. The judgement of NVC is a critical step in the preoperative evaluation of MVD, which is related to the effect of MVD treatment. Magnetic resonance imaging(MRI) technology has been used to detect NVC prior to MVD for several years. Among many MRI sequences, three-dimensional time-of-flight magnetic resonance angiography(3D TOF MRA) is the most widely used. However, 3D TOF MRA has some shortcomings in detecting NVC. Therefore, 3D TOF MRA combined with high resolution T2-weighted imaging(HR T2WI) is considered to be a more effective method to detect NVC.AIM To determine the value of 3D TOF MRA combined with HR T2WI in the judgment of NVC, and thus to assess its value in the preoperative evaluation of MVD.METHODS Related studies published from inception to September 2022 based on PubMed, Embase, Web of Science, and the Cochrane Library were retrieved. Studies that investigated 3D TOF MRA combined with HR T2WI to judge NVC in patients with TN or HFS were included according to the inclusion criteria. Studies without complete data or not relevant to the research topics were excluded. The Quality Assessment of Diagnostic Accuracy Studies checklist was used to assess the quality of included studies. The publication bias of the included literature was examined by Deeks’ test. An exact binomial rendition of the bivariate mixed-effects regression model was used to synthesize data. Data analysis was performed using the MIDAS module of statistical software Stata 16.0. Two independent investigators extracted patient and study characteristics, and discrepancies were resolved by consensus. Individual and pooled sensitivities and specificities were calculated. The I_(2) statistic and Q test were used to test heterogeneity. The study was registered on the website of PROSERO(registration No. CRD42022357158).RESULTS Our search identified 595 articles, of which 12(including 855 patients) fulfilled the inclusion criteria. Bivariate analysis showed that the pooled sensitivity and specificity of 3D TOF MRA combined with HR T2WI for detecting NVC were 0.96 [95% confidence interval(CI): 0.92-0.98] and 0.92(95%CI: 0.74-0.98), respectively. The pooled positive likelihood ratio was 12.4(95%CI: 3.2-47.8), pooled negative likelihood ratio was 0.04(95%CI: 0.02-0.09), and pooled diagnostic odds ratio was 283(95%CI: 50-1620). The area under the receiver operating characteristic curve was 0.98(95%CI: 0.97-0.99). The studies showed no substantial heterogeneity(I2 = 0, Q = 0.001 P = 0.50).CONCLUSION Our results suggest that 3D TOF MRA combined with HR T2WI has excellent sensitivity and specificity for judging NVC in patients with TN or HFS. This method can be used as an effective tool for preoperative evaluation of MVD.

Magnetic Resonance Perfusion Imaging in the Diagnosis of High-Grade Glioma Progression and Treatment-Related Changes: A Systematic Review

In patients with high grade gliomas (HGGs), progression after treatment can be difficult to diagnose due to treatment-related effects, which overlap in appearance with tumour progression on conventional magnetic resonance imaging (MRI) sequences. Specialised imaging methods have been studied for this purpose, though most institutions currently use histopathology or clinicoradiological follow-up for diagnosis. This publication aims to review the evidence for perfusion MRI techniques. The databases of Pubmed, MEDLINE, EMBASE and Scopus were searched using combinations of the subject headings high grade glioma and MRI perfusion. 41 articles fulfilled the inclusion criteria. Dynamic Susceptibility Contrast (DSC) MRI was the most extensively studied, with several studies achieving high sensitivities and specificities. Other techniques exhibiting potential include Dynamic Contrast Enhanced (DCE) MRI, Arterial Spin Labelling (ASL). However, these techniques are not widely used or available for clinical practice. Composite measures combining results from multiple techniques tended to achieve higher accuracies. Some publications compared processing software used or looked at machine learning with relative success. An issue common to the literature is the lack of standardisation in the reference standard and acquisition/processing methods. Furthermore, many had small sample sizes, and further consideration needs to be given with regards to timing of imaging, and treatment regimens received in such studies.

Flexible reduced field of view magnetic resonance imaging based on single-shot spatiotemporally encoded technique

In many ultrafast imaging applications, the reduced field-of-view（r FOV） technique is often used to enhance the spatial resolution and field inhomogeneity immunity of the images. The stationary-phase characteristic of the spatiotemporallyencoded（SPEN） method offers an inherent applicability to r FOV imaging. In this study, a flexible r FOV imaging method is presented and the superiority of the SPEN approach in r FOV imaging is demonstrated. The proposed method is validated with phantom and in vivo rat experiments, including cardiac imaging and contrast-enhanced perfusion imaging. For comparison, the echo planar imaging（EPI） experiments with orthogonal RF excitation are also performed. The results show that the signal-to-noise ratios of the images acquired by the proposed method can be higher than those obtained with the r FOV EPI. Moreover, the proposed method shows better performance in the cardiac imaging and perfusion imaging of rat kidney, and it can scan one or more regions of interest（ROIs） with high spatial resolution in a single shot. It might be a favorable solution to ultrafast imaging applications in cases with severe susceptibility heterogeneities, such as cardiac imaging and perfusion imaging. Furthermore, it might be promising in applications with separate ROIs, such as mammary and limb imaging.

Renal ablation using magnetic resonance-guided high intensity focused ultrasound: Magnetic resonance imaging and histopathology assessment

AIM: To use magnetic resonance-guided high intensity focused ultrasound(MRg-HIFU), magnetic resonance imaging(MRI) and histopathology for noninvasively ablating, quantifying and characterizing ablated renal tissue. METHODS: Six anesthetized/mechanically-ventilated pigs underwent single/double renal sonication(n = 24) using a 3T-MRg-HIFU(1.1 MHz frequency and 3000J-4400 J energies). T2-weighted fast spin echo(T2-W), perfusion saturation recovery gradient echo and contrast enhanced(CE) T1-weighted(T1-W) sequences were used for treatment planning, temperature monitoring, lesion visualization, characterization and quantification, respectively. Histopathology was conducted in excised kidneys to quantify and characterize cellular and vascular changes. Paired Student's t-test was used and a P-value < 0.05 was considered statistically significant.RESULTS: Ablated renal parenchyma could not be differentiated from normal parenchyma on T2-W or nonCE T1-W sequences. Ablated renal lesions were visible as hypoenhanced regions on perfusion and CE T1-W MRI sequences, suggesting perfusion deficits and necrosis. Volumes of ablated parenchyma on CE T1-W images invivo(0.12-0.36 cm3 for single sonication 3000 J, 0.50-0.84 cm3, for double 3000 J, 0.75-0.78 cm3 for single 4400 J and 0.12-2.65 cm3 for double 4400J) and at postmortem(0.23-0.52 cm3, 0.25-0.82 cm3, 0.45-0.68 cm3 and 0.29-1.80 cm3, respectively) were comparable. The ablated volumes on 3000 J and 4400 J double sonication were significantly larger than single(P < 0.01), thus, the volume and depth of ablated tissue depends on the applied energy and number of sonication. Macroscopic and microscopic examinations confirmed the locations and presence of coagulation necrosis, vascular damage and interstitial hemorrhage, respectively.CONCLUSION: Contrast enhanced MRI provides assessment of MRg-HIFU renal ablation. Histopathology demonstrated coagulation necrosis, vascular damage and confirmed the volume of damage seen on MRI.

Performance study of aluminum shielded room for ultra-low-field magnetic resonance imaging based on SQUID： Simulations and experiments

The aluminum shielded room has been an important part of ultra-low-field magnetic resonance imaging （ULF MRI） based on the superconducting quantum interference device （SQUID）. The shielded room is effective to attenuate the external radio-frequency field and keep the extremely sensitive detector, SQUID, working properly. A high-performance shielded room can increase the signal-to-noise ratio （SNR） and improve image quality. In this study, a circular coil with a diameter of 50 cm and a square coil with a side length of 2.0 m was used to simulate the magnetic fields from the nearby electric apparatuses and the distant environmental noise sources. The shielding effectivenesses （SE） of the shielded room with different thicknesses of aluminum sheets were calculated and simulated. A room using 6-mm-thick aluminum plates with a dimension of 1.5 m x 1.5 m x 2.0 m was then constructed. The SE was experimentally measured by using three-axis SQUID magnetometers, with tranisent magnetic field induced in the aluminum plates by the strong pre-polarization pulses. The results of the measured SE agreed with that from the simulation. In addition, the introduction of a 0.5-mm gap caused the obvious reduction of SE indicating the importance of door design. The nuclear magnetic resonance （NMR） signals of water at 5.9 kHz were measured in free space and in a shielded room, and the SNR was improved from 3 to 15. The simulation and experimental results will help us design an aluminum shielded room which satisfies the requirements for future ULF human brain imaging. Finally, the cancellation technique of the transient eddy current was tried, the simulation of the cancellation technique will lead us to finding an appropriate way to suppress the eddy current fields.

Magnetic resonance image-guided versus ultrasound-guided high-intensity focused ultrasound in the treatment of breast cancer

Image-guided high-intensity focused ultrasound (HIFU) has been used for more than ten years, primarily in the treatment of liver and prostate cancers. HIFU has the advantages of precise cancer ablation and excellent protection of healthy tissue. Breast cancer is a common cancer in women. HIFU therapy, in combination with other therapies, has the potential to improve both oncologic and cosmetic outcomes for breast cancer patients by providing a curative therapy that conserves mammary shape. Currently, HIFU therapy is not commonly used in breast cancer treatment, and efforts to promote the application of HIFU is expected. In this article, we compare different image-guided models for HIFU and reviewed the status, drawbacks, and potential of HIFU therapy for breast cancer.

Analysis of clinical characteristics of leptomeningeal metastasis with band-like high signal in the brainstem

Objective:The aim was to analyse the clinical features of leptomeningeal metastasis with banded high signal in the brainstem.Methods:In this paper,we report two cases of lung adenocarcinoma with soft meningeal metastasis,collected from the First Affiliated Hospital of Hainan Medical College,and searched the databases of CNKI,Wanfang,VIP,PubMed,Web of Science,and other databases which reported the MRI manifestation of"brainstem bandlike high signal",and collected the patients'past medical history,symptoms,signs,genetic findings,cerebrospinal fluid manifestation,treatment,and prognosis.Result:A total of 28 patients were included,of whom 26 had a history of lung adenocarcinoma and 2 were found to have occupational changes in the lungs.Magnetic resonance imaging(MRI)showed a band-like high signal in the ventral part of the brainstem on T2-FLAIR,symmetrical on both sides,which could extend to the cerebellar peduncles,with high signals on diffusion-weighted imaging(DWI),low signals on apparent diffusion coefficient(ADC),and long T1 signals on T1-weighted imaging,long T2 signals on T2 weighted imaging,and no long T2 signals on enhancement scan.T1-weighted imaging was a long T1 signal,T2-weighted imaging was a long T2 signal,and no enhancement was seen on enhanced scanning.Conclusion:It is important to recognize leptomeningeal metastasis of lung cancer,and the non-enhancing band of high signal in the brainstem on T2-FLAIR and DWI is likely to be the characteristic manifestation of leptomeningeal metastasis of non-small cell lung cancer.

3.0 Tesla magnetic resonance imaging: A new standard in liver imaging?

An ever-increasing number of 3.0 Tesla(T) magnets are installed worldwide. Moving from the standard of 1.5 T to higher field strength implies a number of potential advantage and drawbacks, requiring careful optimization of imaging protocols or implementation of novel hardware components. Clinical practice and literature review suggest that state-of-the-art 3.0 T is equivalent to 1.5 T in the assessment of focal liver lesions and diffuse liver disease. Therefore, further technical improvements are needed in order to fully exploit the potential of higher field strength.

Intraoperative magnetic resonance imaging in neurosurgery and anesthetic considerations

Currently, magnetic resonance imaging(MRI) is the only imaging modality available which is capable of acquiring intra-operative images frequently with acceptable spatial and contrast resolution. However, the incorporation of MRI technology into the operating room requires special anesthetic considerations. It may include various aspects such as transport, remote location anesthesia, strong electromagnetic field, use of approved items, equipment counts, possible emergencies, and surgery in awake patients. The patient safety may be compromised by health-related, equipment-related, and procedure-related risks. Direct patient observation may be compromised by acoustic noise, darkened environment, obstructed line of sight, and distractions along with difficult access to the patient for airway management. Most often, the patient's head will be 180° away from the anesthesiologist during the procedure. Several monitors exist that are designed for conditional use in a MR environment. The general design criterion in these monitors is to eliminate conductors that carry electrical signals for monitoring physiologic parameters of the patient. General anesthesia requires an extended anesthetic circuit for ventilation maintenance and drug administration because the patient is located farther from the anesthesia machine than in traditional operating room settings. Dead space creates a time delay before the volatile anesthetic and drugs are administered and when expected effects can be observed. Therefore, the attending anaesthesiologists must understand the above aspects for safe conduct of neurosurgical procedures by minimizing MRI associated accidents while assuring optimal patient vigilance.

3.0 T proton magnetic resonance spectroscopy of the liver: Quantification of choline

AIM: To investigate the normal hepatic magnetic resonance spectroscopy findings choline/lipid2 (Cho/Lip2) associated with age and body mass index (BMI).METHODS: A total of 58 single-voxel proton spectra of the liver were acquired at 3.0 T using the eightchannel phased array abdominal coil as the receiver coil. Consecutive stacks of breath-hold spectra were acquired using the point resolved spectroscopy technique at a short echo time of 30 ms and a repetition time of 1500 ms. The spectra were processed with the SAGE software package. Areas and heights for metabolite resonance were obtained. Student's t test for unpaired data was used for comparisons of shimming, Cho/Lip2, and lipid content. RESULTS: There were significant negative correlations between the Cho/Lip2 peak height ratios and BMI (r=-0.615) and age (r=-0.398) (all P<0.01). Compared with the high-BMI group, the low-BMI group was younger (39.1±13.0 years vs 47.6±8.5 years, t=-2.954,P=0.005); had better water suppression (93.4%±1.4% vs 85.6%±11.6%, t=2.741, P=0.014); had higher Cho/Lip2 peak heights ratio (0.2±0.14 vs 0.05±0.04,t=6.033,P<0.000); and had lower lipid content (0.03±0.08 vs 0.29±0.31, t=-3.309, P=0.004). Compared with the older group, the younger group had better shimming effects (17.1±3.6 Hz vs 22.0±6.8 Hz, t=-2.919, P=0.008); higher Cho/Lip2 peak heights ratios (0.03±0.05vs 0.09±0.12,t=2.4, P=0.020); and lower lipid content (0.05±0.11 vs 0.23±0.32,t=-2.337,P=0.031). Compared with the lowcholine peak group, the high-choline peak group had lower lipid content (0.005±0.002 vs 0.13±0.23, t=-3.796,P<0.000); lower BMI (19.6±2.4vs 23.9±3.0, t=-4.410, P<0.000); and younger age (34.7±10.0 years vs 43.2±12.5 years, t=-2.088, P=0.041). CONCLUSION: Lipid accumulation could result from the increased fat in the body depending on age and BMI. Lipid can mask the resonance signal of choline.

Application of nuclear magnetic resonance technology to carbon capture,utilization and storage:A review

Carbon capture,utilization and storage (CCUS) is considered as a very important technology for mitigating global climate change.Carbon dioxide (CO2) injected into an underground reservoir will induce changes in its physical properties and the migration of CO2 will be affected by many factors.Accurately understanding these changes and migration characteristics of CO2 is crucial for selecting a CCUS project site,estimating storage capacity and ensuring storage security.In this paper,the basic principles of nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) technologies are briefly introduced in the context of laboratory experiments related to CCUS.The types of NMR apparatus,experimental samples and testing approaches applied worldwide are discussed and analyzed.Then two typical NMR core analysis systems used in CCUS field and a self-developed high-pressure,low-field NMR rock core flooding experimental system are compared.Finally,a summary of the current deficiencies related to NMR applied to CCUS field is given and future research plans are proposed.

Effect of MR Field Strength on the Texture Features of Cerebral T2-FLAIR Images: A Pilot Study

Objective To investigate effect of MR field strength on texture features of cerebral T2 fluid attenuated inversion recovery(T2-FLAIR)images.Methods We acquired cerebral 3 D T2-FLAIR images of thirty patients who were diagnosed with ischemic white matter lesion(WML)with MR-1.5 T and MR-3.0 T scanners.Histogram texture features which included mean signal intensity(Mean),Skewness and Kurtosis,and gray level co-occurrence matrix(GLCM)texture features which included angular second moment(ASM),Contrast,Correlation,Inverse difference moment(IDM)and Entropy,of regions of interest located in the area of WML and normal white matter(NWM)were measured by ImageJ software.The texture parameters acquired with MR-1.5 T scanning were compared with MR-3.0 T scanning.Results The Mean of both WML and NWM obtained with MR-1.5 T scanning was significantly lower than that acquired with MR-3.0 T(P<0.001),while Skewness and Kurtosis between MR-1.5 T and MR-3.0 T scanning showed no significant difference(P>0.05).ASM,Correlation and IDM of both WML and NWM acquired with MR-1.5 T revealed significantly lower values than those with MR-3.0 T(P<0.001),while Contrast and Entropy acquired with MR-1.5 T showed significantly higher values than those with MR-3.0 T(P<0.001).Conclusion MR field strength showed no significant effect on histogram textures,while had significant effect on GLCM texture features of cerebral T2-FLAIR images,which indicated that it should be cautious to explain the texture results acquired based on the different MR field strength.

Nuclear magnetic resonance measurement station in SECUF using hybrid superconducting magnets

Nuclear magnetic resonance （NMR） is one of the most powerful tools to explore new quantum states of condensed matter induced by high magnetic fields at a microscopic level. High magnetic field enhances the intensity of the NMR signal, and more importantly, can induce novel phenomena. In this article, examples are given on the field-induced charge density wave （CDW） in high-To superconductors and on the studies of quantum spin liquids. We provide a brief introduction to the high magnetic field NMR platform, the station 4 of the Synergetic Extreme Condition User Facility （SECUF）, being built at Huairou, Beijing.

7.0T nuclear magnetic resonance evaluation of the amyloid beta(1–40) animal model of Alzheimer's disease: comparison of cytology verification

3.0T magnetic resonance spectroscopic imaging brain function in Alzheimer＇s disease. However, is a commonly used method in the research ot the role of 7.0T high-field magnetic resonance spectroscopic imaging in brain function of Alzheimer＇s disease remains unclear. In this study, 7.0T magnetic resonance spectroscopy showed that in the hippocampus of Alzheimer＇s disease rats, the N-acetylaspartate wave crest was reduced, and the creatine and choline wave crest was elevated. This finding was further supported by hematoxylin-eosin staining, which showed a loss of hippocampal neurons and more glial cells. Moreover, electron microscopy showed neuronal shrinkage and mitochondrial rupture, and scanning electron microscopy revealed small size hippocampal synaptic vesicles, incomplete synaptic structure, and reduced number. Overall, the results revealed that 7.0T high-field nuclear magnetic resonance spectroscopy detected the lesions and functional changes in hippocampal neurons of Alzheimer＇s disease rats in vivo, allowing the possibility for assessing the success rate and grading of the amyloid beta （1-40） animal model of Alzheimer＇s disease.

Investigation of the Value of Different Field Strength MRI Scans for the Diagnosis of Rotator Cuff in Juries

Objective: A comparison of the difference between the two types of field MR scan in diagnosis of shoulder joint injury. Method: Randomly selected 153 patients with arthroscopic or open arthroplasty who had shoulder pain or dysfunction treated in our hospital from 2014 to 2017 were divided into 1.5 T group and 3.0 according to the field strength of MRI examination. Postoperative pathology was a gold standard. The sensitivity, specificity, consistency, and predictive value of two field-strength MRI examinations in the diagnosis of rotator cuff tears were calculated and compared. Results: The sensitivity, specificity, crude consistency, positive predictive value, and negative predictive value of the 1.5 T group were 68.75%, 82.35%, 73.47%, 88.00%, and 58.33%, respectively. The 3.0 T group was 72.22%, 89.47%, 78.18%, 92.86% and 62.96%, the differences between the above indicators were not statistically significant (P > 0.05). Conclusion: There was no difference in the authenticity and benefit index of rotator cuff injury diagnosed by 1.5 T and 3.0 T MRI.

Impact of cognition-related single nucleotide polymorphisms on brain imaging phenotype in Parkinson’s disease

Multiple single nucleotide polymorphisms may contribute to cognitive decline in Parkinson’s disease. However, the mechanism by which these single nucleotide polymorphisms modify brain imaging phenotype remains unclear. The aim of this study was to investigate the potential effects of multiple single nucleotide polymorphisms on brain imaging phenotype in Parkinson’s disease. Forty-eight Parkinson’s disease patients and 39 matched healthy controls underwent genotyping and 7 T magnetic resonance imaging. A cognitive-weighted polygenic risk score model was designed, in which the effect sizes were determined individually for 36 single nucleotide polymorphisms. The correlations between polygenic risk score, neuroimaging features, and clinical data were analyzed. Furthermore, individual single nucleotide polymorphism analysis was performed to explore the main effects of genotypes and their interactive effects with Parkinson’s disease diagnosis. We found that, in Parkinson’s disease, the polygenic risk score was correlated with the neural activity of the hippocampus, parahippocampus, and fusiform gyrus, and with hippocampal-prefrontal and fusiform-temporal connectivity, as well as with gray matter alterations in the orbitofrontal cortex. In addition, we found that single nucleotide polymorphisms in α-synuclein(SNCA) were associated with white matter microstructural changes in the superior corona radiata, corpus callosum, and external capsule. A single nucleotide polymorphism in catechol-O-methyltransferase was associated with the neural activities of the lingual, fusiform, and occipital gyri, which are involved in visual cognitive dysfunction. Furthermore, DRD3 was associated with frontal and temporal lobe function and structure. In conclusion, imaging genetics is useful for providing a better understanding of the genetic pathways involved in the pathophysiologic processes underlying Parkinson’s disease. This study provides evidence of an association between genetic factors, cognitive functions, and multi-modality neuroimaging biomarkers in Parkinson’s disease.

基于不同维度低场核磁共振技术的大豆含油率检测与判别

大豆含油率的高低直接影响榨油与育种结果。为探究大豆含油率的最佳检测方法与构建含油率高低判别模型,该研究基于不同维度低场核磁共振(low field nuclear magnetic resonance,LF-NMR)技术,以国标法为对照,利用LF-NMR波谱和LF-NMR含油含水率软件检测大豆含油率;核磁共振成像(magnetic resonance imaging,MRI)结合深度学习,建立大豆含油率高低判别模型。引入低场二维核磁共振(low field two-dimensional nuclear magnetic resonance,LF-2D-NMR)技术,定性分析一维波谱中信号重叠无法区分组分的问题。试验结果表明,LF-NMR含油含水率软件能快速准确检测大豆含油率,T1-T2二维核磁图谱成功解决了自由水和油信号重叠问题。利用U-net++深度学习模型对MRI成像的矢状面、冠状面、横截面以及三面混合数据集进行训练,其中横截面评价指标与其他数据集相比更优,语义分割部分中平均交并比(mean intersection over union,mIoU)约0.9058,全局准确率0.9980,训练后的模型能够将MRI图像识别并分割,快速判别大豆含油率高低。试验证明,LF-NMR及MRI能够快速无损掌握大豆含油率信息,为大豆的高油育种提供了新思路和技术支持。