Journal articles: 'Electrical source imaging (ESI)'

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Thurairajah, Arun. "Role of Electrical Source Imaging in Pediatric Epilepsy and Pre-Surgical Evaluation." Sciential - McMaster Undergraduate Science Journal, no. 6 (April 12, 2021): 10–14. http://dx.doi.org/10.15173/sciential.vi6.2645.

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Children with drug-resistant epilepsy undergo an extensive pre-surgical evaluation to determine the part of the brain thought to be the cause of seizures. The employment of non-invasive diagnostic imaging tools plays an important role in establishing surgical candidacy, preventing the need for invasive procedures. Electrical source imaging (ESI) has been explored as a modern alternative to traditional diagnostic techniques in pre-surgical workup. Through computational analysis of recorded electric potentials and individualized head scans, ESI provides a non-invasive method of obtaining more accurate localizations. However, its use within the clinical setting is limited. The following review looks to examine the literature surrounding ESI and advocates for its inclusion within the pre-surgical workup of children.

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Zorzos, Ioannis, Ioannis Kakkos, Errikos M. Ventouras, and George K. Matsopoulos. "Advances in Electrical Source Imaging: A Review of the Current Approaches, Applications and Challenges." Signals 2, no. 3 (June 24, 2021): 378–91. http://dx.doi.org/10.3390/signals2030024.

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Brain source localization has been consistently implemented over the recent years to elucidate complex brain operations, pairing the high temporal resolution of the EEG with the high spatial estimation of the estimated sources. This review paper aims to present the basic principles of Electrical source imaging (ESI) in the context of the recent progress for solving the forward and the inverse problems, and highlight the advantages and limitations of the different approaches. As such, a synthesis of the current state-of-the-art methodological aspects is provided, offering a complete overview of the present advances with regard to the ESI solutions. Moreover, the new dimensions for the analysis of the brain processes are indicated in terms of clinical and cognitive ESI applications, while the prevailing challenges and limitations are thoroughly discussed, providing insights for future approaches that could help to alleviate methodological and technical shortcomings.

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Khosropanah, Pegah, Eric Tatt-Wei Ho, Kheng-Seang Lim, Si-Lei Fong, Minh-An Thuy Le, and Vairavan Narayanan. "EEG Source Imaging (ESI) utility in clinical practice." Biomedical Engineering / Biomedizinische Technik 65, no. 6 (November 18, 2020): 673–82. http://dx.doi.org/10.1515/bmt-2019-0128.

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AbstractEpilepsy surgery is an important treatment modality for medically refractory focal epilepsy. The outcome of surgery usually depends on the localization accuracy of the epileptogenic zone (EZ) during pre-surgical evaluation. Good localization can be achieved with various electrophysiological and neuroimaging approaches. However, each approach has its own merits and limitations. Electroencephalography (EEG) Source Imaging (ESI) is an emerging model-based computational technique to localize cortical sources of electrical activity within the brain volume, three-dimensionally. ESI based pre-surgical evaluation gives an overall clinical yield of 73–91%, depending on choice of head model, inverse solution and EEG electrode density. It is a cost effective, non-invasive method which provides valuable additional information in presurgical evaluation due to its high localizing value specifically in MRI-negative cases, extra or basal temporal lobe epilepsy, multifocal lesions such as tuberous sclerosis or cases with multiple hypotheses. Unfortunately, less than 1% of surgical centers in developing countries use this method as a part of pre-surgical evaluation. This review promotes ESI as a useful clinical tool especially for patients with lesion-negative MRI to determine EZ cost-effectively with high accuracy under the optimized conditions.

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Mattioli, Pietro, Evy Cleeren, Levente Hadady, Alberto Cossu, Thomas Cloppenborg, Dario Arnaldi, and Sándor Beniczky. "Electric Source Imaging in Presurgical Evaluation of Epilepsy: An Inter-Analyser Agreement Study." Diagnostics 12, no. 10 (September 24, 2022): 2303. http://dx.doi.org/10.3390/diagnostics12102303.

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Electric source imaging (ESI) estimates the cortical generator of the electroencephalography (EEG) signals recorded with scalp electrodes. ESI has gained increasing interest for the presurgical evaluation of patients with drug-resistant focal epilepsy. In spite of a standardised analysis pipeline, several aspects tailored to the individual patient involve subjective decisions of the expert performing the analysis, such as the selection of the analysed signals (interictal epileptiform discharges and seizures, identification of the onset epoch and time-point of the analysis). Our goal was to investigate the inter-analyser agreement of ESI in presurgical evaluations of epilepsy, using the same software and analysis pipeline. Six experts, of whom five had no previous experience in ESI, independently performed interictal and ictal ESI of 25 consecutive patients (17 temporal, 8 extratemporal) who underwent presurgical evaluation. The overall agreement among experts for the ESI methods was substantial (AC1 = 0.65; 95% CI: 0.59–0.71), and there was no significant difference between the methods. Our results suggest that using a standardised analysis pipeline, newly trained experts reach similar ESI solutions, calling for more standardisation in this emerging clinical application in neuroimaging.

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Peters, Jurriaan M., Catherine J. Chu, Merel Boom, Joseph Madsen, Scellig S. Stone, Hakim Ouaalam, Sanjay Prabhu, Mustafa Sahin, Simon Warfield, and Damon E. Hyde. "F162. Lesion-Constrained Electrical Source Imaging (LC-ESI) in epilepsy surgery for tuberous sclerosis complex: A pilot study." Clinical Neurophysiology 129 (May 2018): e128-e129. http://dx.doi.org/10.1016/j.clinph.2018.04.325.

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Maziero, Danilo, Marcio Sturzbecher, Tonicarlo Rodrigues Velasco, Carlo Rondinoni, Agustin Lage Castellanos, David William Carmichael, and Carlos Ernesto Garrido Salmon. "A Comparison of Independent Component Analysis (ICA) of fMRI and Electrical Source Imaging (ESI) in Focal Epilepsy Reveals Misclassification Using a Classifier." Brain Topography 28, no. 6 (May 22, 2015): 813–31. http://dx.doi.org/10.1007/s10548-015-0436-4.

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Quintiliani, Michela, Federico Bianchi, Filomena Fuggetta, Daniela Pia Rosaria Chieffo, Antonia Ramaglia, Domenica Immacolata Battaglia, and Gianpiero Tamburrini. "Role of high-density EEG (hdEEG) in pre-surgical epilepsy evaluation in children: case report and review of the literature." Child's Nervous System 37, no. 5 (February 18, 2021): 1429–37. http://dx.doi.org/10.1007/s00381-021-05069-z.

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Abstract Introduction Electrical source imaging (ESI) and especially hdEEG represent a noninvasive, low cost and accurate method of localizing epileptic zone (EZ). Such capability can greatly increase seizure freedom rate in surgically treated drug resistant epilepsy cases. Furthermore, ESI might be important in intracranial record planning. Case report We report the case of a 15 years old boy suffering from drug resistant epilepsy with a previous history of DNET removal. The patient suffered from heterogeneous seizure semiology characterized by anesthesia and loss of tone in the left arm, twisting of the jaw to the left and dysarthria accompanied by daze; lightheadedness sometimes associated with headache and dizziness and at a relatively short time distance negative myoclonus involving the left hand. Clinical evidence poorly match scalp and video EEG monitoring thus requiring hdEEG recording followed by SEEG to define surgical target. Surgery was also guided by ECoG and obtained seizure freedom. Discussion ESI offers an excellent estimate of EZ, being hdEEG and intracranial recordings especially important in defining it. We analyzed our results together with the data from the literature showing how in children hdEEG might be even more crucial than in adults due to the heterogeneity in seizures phenomenology. The complexity of each case and the technical difficulties in dealing with children, stress even more the importance of a noninvasive tool for diagnosis. In fact, hdEEG not only guided in the presented case SEEG planning but may also in the future offer the possibility to replace it.

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Rikir, Estelle, Laurent Koessler, Martine Gavaret, Fabrice Bartolomei, Sophie Colnat-Coulbois, Jean-Pierre Vignal, Herve Vespignani, Georgia Ramantani, and Louis G. Maillard. "Electrical source imaging in cortical malformation-related epilepsy: A prospective EEG-SEEG concordance study." Epilepsia 55, no. 6 (April 4, 2014): 918–32. http://dx.doi.org/10.1111/epi.12591.

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Schwarz, Gabriele, Gertraud Puttinger, and Tim J. von Oertzen. "Prächirurgische Epilepsiediagnostik – öfter ein Thema als viele denken." psychopraxis. neuropraxis 22, no. 6 (November 12, 2019): 260–67. http://dx.doi.org/10.1007/s00739-019-00592-w.

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Zusammenfassung Epilepsiechirurgie ist eine hochwirksame Therapie mit kurativem Anspruch. Dies belegen inzwischen 3 Studien mit Klasse-1-Evidenz. Bei pharmakoresistenter fokaler Epilepsie mit einer Krankheitsdauer von fast 20 Jahren, mit kürzerer Krankheitsdauer von durchschnittlich 5 Jahren sowie bei Kindern wurde jeweils unabhängig voneinander gezeigt, dass Epilepsiechirurgie dem „best medical treatment“ hochsignifikant überlegen ist. Mithilfe multimodaler Untersuchungsmethoden (z. B. Langzeit-Video-EEG, hochauflösendes cMRT nach Epilepsieprotokoll, FDG-PET, neuropsychologische Testung, fMRT, ev. iktale SPECT-Untersuchung und Verrechnung mittels SISCOM, Postprocessing des cMRTs, „electric source imaging“ [ESI], Magnetenzephalographie [MEG], invasive Abklärung mittels Stereo-EEG-Elektroden oder subduralen Elektroden und WADA-Test) ist es in der prächirurgischen Epilepsiediagnostik nun möglich, Patienten einen epilepsiechirurgischen Eingriff anzubieten, die früher als schlechte oder aussichtslose Kandidaten für eine Epilepsiechirurgie eingeschätzt wurden.

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Patel, Sutchin, Nicholas Rotker, and Anthony Caldamone. "How a Rock Band, a Recording Company, and a Nobel Laureate Developed Computed Tomography." International Journal of Urologic History 2, no. 2 (January 5, 2023): 44–51. http://dx.doi.org/10.53101/ijuh.2.2.01052303.

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Objectives Computed Tomography (CT) is an indispensable element of medical care used throughout the world, and first developed for clinical use by Hounsfield in 1971. The largest source of monetary support for Hounsfield’s work was from his employer, Electrical Musical Industries, Ltd. (EMI) and, in turn, the most lucrative source of income for EMI through the 1960’s was their recording contract with the English quartet, the Beatles. The purported link between the Beatles’ productive oeuvre with EMI and Hounsfield’s discovery of CT has not been well established. We endeavored to elucidate the technological and creative talents that linked Hounsfield with EMI and the Beatles and which ultimately led to one of the greatest medical innovations of the 20th century. Methods We used GoogleScholar, PubMed, and primary sources to research the life of Godfrey Hounsfield, the history of Electric and Musical Industries, Ltd (EMI), and The Beatles in reference to the development of CT. We used the EMI Archives Trust (London), and the archives of the Institute of Electrical and Electronics Engineers (IEEE) UK and Ireland (London). We obtained unpublished photographs courtesy of private collections. Results EMI translated its electronic prowess during WWII into the recorded music business, purchasing Capitol Records in 1955. EMI would sign The Beatles in 1963 and EMI profits rose 80% that first year. Sir Godfrey Hounsfield began a successful scientific career with EMI in 1951. With financial support from EMI’s research division, Hounsfield began developing what would become the first CT-scanner in 1967. By directing x-ray beams through the body at 1 degree angles, with a detector rotating in tandem on the other side, he could measure the x-ray attenuation of different tissues inside the body. These values were then analyzed via a mathematical algorithm to produce a 2-dimensional image of the slice of the body. Hounsfield worked with James Ambrose, a radiologist, to conduct the first clinical CT-scan at Atkinson Morley Hospital in 1971 in a patient with a brain tumor. EMI entered the medical equipment business thereafter and heavily marketed the CT-scanner using the financial resources EMI derived from its record sales. By 1976, EMI could not produce enough CT-scanners to fill demand and ultimately would cede the medical imaging business to competitors, and devote itself to the music industry. In 1979, Hounsfield, and Allen Cormack, a South African physicist who independently theorized the basis of CT imaging, would win the Nobel Prize. Conclusions ‘Let it be’ known that it was only ‘yesterday’ when a recording company, a rock band, and a radar scientist revolutionized medical imaging with the development of computed tomography.

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Bentley, Laurence R., and Mehran Gharibi. "Two‐ and three‐dimensional electrical resistivity imaging at a heterogeneous remediation site." GEOPHYSICS 69, no. 3 (May 2004): 674–80. http://dx.doi.org/10.1190/1.1759453.

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Geometrically complex heterogeneities at a decommissioned sour gas plant could not be adequately characterized with drilling and 2D electrical resistivity surveys alone. In addition, 2D electrical resistivity imaging profiles produced misleading images as a result of out‐of‐plane resistivity anomalies and violation of the 2D assumption. Accurate amplitude and positioning of electrical conductivity anomalies associated with the subsurface geochemical distribution were required to effectively analyze remediation alternatives. Forward and inverse modeling and field examples demonstrated that 3D resistivity images were needed to properly reconstruct the amplitude and geometry of the complex resistivity anomalies. Problematic 3D artifacts in 2D images led to poor inversion fits and spurious conductivity values in the images at depths close to the horizontal offset of the off‐line anomaly. Three‐dimensional surveys were conducted with orthogonal sets of Wenner and dipole–dipole 2D resistivity survey lines. The 3D inversions were used to locate source zones and zones of elevated ammonium. Thus, conducting 3D electrical resistivity imaging (ERI) surveys early in the site characterization process will improve cost effectiveness at many remediation sites.

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Comas, X., N. Terry, L. Slater, M. Warren, R. Kolka, A. Kristijono, N. Sudiana, D. Nurjaman, and T. Darusman. "Imaging tropical peatlands in Indonesia using ground penetrating radar (GPR) and electrical resistivity imaging (ERI): implications for carbon stock estimates and peat soil characterization." Biogeosciences Discussions 12, no. 1 (January 6, 2015): 191–229. http://dx.doi.org/10.5194/bgd-12-191-2015.

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Abstract. Current estimates of carbon (C) storage in peatland systems worldwide indicate tropical peatlands comprise about 15% of the global peat carbon pool. Such estimates are uncertain due to data gaps regarding organic peat soil thickness and C content. Indonesian peatlands are considered the largest pool of tropical peat carbon (C), accounting for an estimated 65% of all tropical peat while being the largest source of carbon dioxide emissions from degrading peat worldwide, posing a major concern regarding long-term sources of greenhouse gases to the atmosphere. We combined a set of indirect geophysical methods (ground penetrating radar, GPR, and electrical resistivity imaging, ERI) with direct observations from core samples (including C analysis) to better understand peatland thickness in West Kalimantan (Indonesia) and determine how geophysical imaging may enhance traditional coring methods for estimating C storage in peatland systems. Peatland thicknesses estimated from GPR and ERI and confirmed by coring indicated variation by less than 3% even for small peat-mineral soil interface gradients (i.e. below 0.02°). The geophysical data also provide information on peat matrix attributes such as thickness of organomineral horizons between peat and underlying substrate, the presence of wood layers, buttressed trees and soil type. These attributes could further constrain quantification of C content and aid responsible peatland management in Indonesia.

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Seidu, J., A. Ewusi, and J. S. Y. Kuma. "Combined Electrical Resistivity Imaging and Electromagnetic Survey for Groundwater Studies in the Tarkwa Mining Area, Ghana." Ghana Mining Journal 19, no. 1 (June 30, 2019): 29–41. http://dx.doi.org/10.4314/gm.v19i1.4.

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The major source of potable water in Tarkwa is the Bonsa Treatment Plant sourced from the Bonsa River. The activities of illegal miners along the banks of the Bonsa River has resulted in pollution of the river. This has resulted in high treatment cost and irregular supply of water to the Tarkwa Township and surrounding communities that are fed by the Bonsa Treatment Plant. In view of the difficulty in getting frequent and regular potable supply of water, people have resorted to construction of boreholes and hand-dug wells. However, the success rates and borehole yields are low especially in the hydrogeologically difficult terrains in the Tarkwa area. The aim of this paper is to investigate the hydrogeological conditions of the Tarkwa area using both the Electrical Resistivity Imaging (ERI) and Electromagnetic (EM) geophysical techniques to determine the electrical resistivity and conductivity values that are related to groundwater accumulation, so that potential water-bearing zones can be identified. Results from electrical resistivity show that the general resistivity distribution in the Tarkwa area is between 32 Ωm and 100 000 Ωm. Water-bearing zones in the Huni Sandstone occur to a depth of 35 m with an average resistivity value of 400 Ωm, at a depth of 60 m and a resistivity of 600 Ωm in the Tarkwa Phyllite, at a depth of 55 m and a resistivity of 600 Ωm in the Banket Series and 50 m depth with resistivity value of 500 Ωm in the Kawere Conglomerate respectively. The electromagnetic conductivity values also show that the general conductivity distribution in the Tarkwa area is 3 – 32 S/m. The application of electrical resistivity and electromagnetic techniques separately gives success rate of 80 % and 65 % respectively. An improved success rate of 86 % is achieved combining the two techniques. Keywords: Electrical Resistivity Imaging, Electromagnetic Method, Groundwater

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Korompili, Georgia, Konstantinos Misiakos, and Nikos Chronis. "An optoelectronic chip with integrated epi-illumination source and collection optics for imaging applications." Sensors and Actuators A: Physical 312 (September 2020): 112082. http://dx.doi.org/10.1016/j.sna.2020.112082.

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De Landro, Martina, Jacopo Ianniello, Maxime Yon, Alexey Wolf, Bruno Quesson, Emiliano Schena, and Paola Saccomandi. "Fiber Bragg Grating Sensors for Performance Evaluation of Fast Magnetic Resonance Thermometry on Synthetic Phantom." Sensors 20, no. 22 (November 12, 2020): 6468. http://dx.doi.org/10.3390/s20226468.

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The increasing recognition of minimally invasive thermal treatment of tumors motivate the development of accurate thermometry approaches for guaranteeing the therapeutic efficacy and safety. Magnetic Resonance Thermometry Imaging (MRTI) is nowadays considered the gold-standard in thermometry for tumor thermal therapy, and assessment of its performances is required for clinical applications. This study evaluates the accuracy of fast MRTI on a synthetic phantom, using dense ultra-short Fiber Bragg Grating (FBG) array, as a reference. Fast MRTI is achieved with a multi-slice gradient-echo echo-planar imaging (GRE-EPI) sequence, allowing monitoring the temperature increase induced with a 980 nm laser source. The temperature distributions measured with 1 mm-spatial resolution with both FBGs and MRTI were compared. The root mean squared error (RMSE) value obtained by comparing temperature profiles showed a maximum error of 1.2 °C. The Bland-Altman analysis revealed a mean of difference of 0.1 °C and limits of agreement 1.5/−1.3 °C. FBG sensors allowed to extensively assess the performances of the GRE-EPI sequence, in addition to the information on the MRTI precision estimated by considering the signal-to-noise ratio of the images (0.4 °C). Overall, the results obtained for the GRE-EPI fully satisfy the accuracy (~2 °C) required for proper temperature monitoring during thermal therapies.

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Duez, Lene, Hatice Tankisi, Peter Orm Hansen, Per Sidenius, Anne Sabers, Lars H. Pinborg, Martin Fabricius, et al. "Electromagnetic source imaging in presurgical workup of patients with epilepsy." Neurology 92, no. 6 (January 4, 2019): e576-e586. http://dx.doi.org/10.1212/wnl.0000000000006877.

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ObjectiveTo determine the diagnostic accuracy and clinical utility of electromagnetic source imaging (EMSI) in presurgical evaluation of patients with epilepsy.MethodsWe prospectively recorded magnetoencephalography (MEG) simultaneously with EEG and performed EMSI, comprising electric source imaging, magnetic source imaging, and analysis of combined MEG-EEG datasets, using 2 different software packages. As reference standard for irritative zone (IZ) and seizure onset zone (SOZ), we used intracranial recordings and for localization accuracy, outcome 1 year after operation.ResultsWe included 141 consecutive patients. EMSI showed localized epileptiform discharges in 94 patients (67%). Most of the epileptiform discharge clusters (72%) were identified by both modalities, 15% only by EEG, and 14% only by MEG. Agreement was substantial between inverse solutions and moderate between software packages. EMSI provided new information that changed the management plan in 34% of the patients, and these changes were useful in 80%. Depending on the method, EMSI had a concordance of 53% to 89% with IZ and 35% to 73% with SOZ. Localization accuracy of EMSI was between 44% and 57%, which was not significantly different from MRI (49%–76%) and PET (54%–85%). Combined EMSI achieved significantly higher odds ratio compared to electric source imaging and magnetic source imaging.ConclusionEMSI has accuracy similar to established imaging methods and provides clinically useful, new information in 34% of the patients.Classification of evidenceThis study provides Class IV evidence that EMSI had a concordance of 53%–89% and 35%–73% (depending on analysis) for the localization of epileptic focus as compared with intracranial recordings—IZ and SOZ, respectively.

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Ewusi, A., and J. Seidu. "Efficacy of Geophysical Techniques for Groundwater Exploration in the Volta Basin, Northern Region of Ghana." Ghana Mining Journal 20, no. 1 (July 7, 2020): 11–19. http://dx.doi.org/10.4314/gm.v20i1.2.

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Abstract Groundwater, traditionally extracted from hand-dug wells and boreholes is the main drinking water source in the Northern Region of Ghana. Many boreholes have been constructed in the region to increase accessibility to potable water mainly as part of rural water supply projects where borehole siting has to be relatively cheaper. These projects have resulted in low success rates of borehole drilling because of the application of inefficient and simple geophysical techniques supposed to be cheaper. Field surveys were conducted with the Electrical Resistivity Imaging (ERI) technique, Electrokinetic System (EKS) sounding technique and Radon (222Rn) technique with the objectives of determining the best geophysical methods for borehole siting and its efficiency in the Volta Basin (VB) in the Northern Region of Ghana. The surveys were conducted at stations of existing dry and positive boreholes. Results show that the three geophysical techniques are efficient to identify groundwater accumulation zones. The ERI, EKS and 222Rn are efficient to identify discontinuities, calculate hydraulic conductivity of discontinuities and identify areas of water circulation respectively. It is recommended that the ERI be used to obtain discontinuities and weak zones for drilling on rural water supply projects in the VB. The EKS and 222Rn should be conducted to evaluate these features when high yield boreholes are required. Keywords: Geophysical Techniques, Volta Basin, Borehole Drilling, Success Rates

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Ghani, Muhammad U., Farid H. Omoumi, Xizeng Wu, Laurie L. Fajardo, Bin Zheng, and Hong Liu. "Evaluation and comparison of a CdTe based photon counting detector with an energy integrating detector for X-ray phase sensitive imaging of breast cancer." Journal of X-Ray Science and Technology 30, no. 2 (March 15, 2022): 207–19. http://dx.doi.org/10.3233/xst-211028.

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PURPOSE: To compare imaging performance of a cadmium telluride (CdTe) based photon counting detector (PCD) with a CMOS based energy integrating detector (EID) for potential phase sensitive imaging of breast cancer. METHODS: A high energy inline phase sensitive imaging prototype consisting of a microfocus X-ray source with geometric magnification of 2 was employed. The pixel pitch of the PCD was 55μm, while 50μm for EID. The spatial resolution was quantitatively and qualitatively assessed through modulation transfer function (MTF) and bar pattern images. The edge enhancement visibility was assessed by measuring edge enhancement index (EEI) using the acrylic edge acquired images. A contrast detail (CD) phantom was utilized to compare detectability of simulated tumors, while an American College of Radiology (ACR) accredited phantom for mammography was used to compare detection of simulated calcification clusters. A custom-built phantom was employed to compare detection of fibrous structures. The PCD images were acquired at equal, and 30% less mean glandular dose (MGD) levels as of EID images. Observer studies along with contrast to noise ratio (CNR) and signal to noise ratio (SNR) analyses were performed for comparison of two detection systems. RESULTS: MTF curves and bar pattern images revealed an improvement of about 40% in the cutoff resolution with the PCD. The excellent spatial resolution offered by PCD system complemented superior detection of the diffraction fringes at boundaries of the acrylic edge and resulted in an EEI value of 3.64 as compared to 1.44 produced with EID image. At equal MGD levels (standard dose), observer studies along with CNR and SNR analyses revealed a substantial improvement of PCD acquired images in detection of simulated tumors, calcification clusters, and fibrous structures. At 30% less MGD, PCD images preserved image quality to yield equivalent (slightly better) detection as compared to the standard dose EID images. CONCLUSION: CdTe-based PCDs are technically feasible to image breast abnormalities (low/high contrast structures) at low radiation dose levels using the high energy inline phase sensitive imaging technique.

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Céspedes-Villar, Yohan, Juan David Martinez-Vargas, and G. Castellanos-Dominguez. "Influence of Patient-Specific Head Modeling on EEG Source Imaging." Computational and Mathematical Methods in Medicine 2020 (April 3, 2020): 1–15. http://dx.doi.org/10.1155/2020/5076865.

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Electromagnetic source imaging (ESI) techniques have become one of the most common alternatives for understanding cognitive processes in the human brain and for guiding possible therapies for neurological diseases. However, ESI accuracy strongly depends on the forward model capabilities to accurately describe the subject’s head anatomy from the available structural data. Attempting to improve the ESI performance, we enhance the brain structure model within the individual-defined forward problem formulation, combining the head geometry complexity of the modeled tissue compartments and the prior knowledge of the brain tissue morphology. We validate the proposed methodology using 25 subjects, from which a set of magnetic-resonance imaging scans is acquired, extracting the anatomical priors and an electroencephalography signal set needed for validating the ESI scenarios. Obtained results confirm that incorporating patient-specific head models enhances the performed accuracy and improves the localization of focal and deep sources.

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Ojeda, Alejandro, Kenneth Kreutz-Delgado, and Jyoti Mishra. "Bridging M/EEG Source Imaging and Independent Component Analysis Frameworks Using Biologically Inspired Sparsity Priors." Neural Computation 33, no. 9 (August 19, 2021): 2408–38. http://dx.doi.org/10.1162/neco_a_01415.

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Abstract Electromagnetic source imaging (ESI) and independent component analysis (ICA) are two popular and apparently dissimilar frameworks for M/EEG analysis. This letter shows that the two frameworks can be linked by choosing biologically inspired source sparsity priors. We demonstrate that ESI carried out by the sparse Bayesian learning (SBL) algorithm yields source configurations composed of a few active regions that are also maximally independent from one another. In addition, we extend the standard SBL approach to source imaging in two important directions. First, we augment the generative model of M/EEG to include artifactual sources. Second, we modify SBL to allow for efficient model inversion with sequential data. We refer to this new algorithm as recursive SBL (RSBL), a source estimation filter with potential for online and offline imaging applications. We use simulated data to verify that RSBL can accurately estimate and demix cortical and artifactual sources under different noise conditions. Finally, we show that on real error-related EEG data, RSBL can yield single-trial source estimates in agreement with the experimental literature. Overall, by demonstrating that ESI can produce maximally independent sources while simultaneously localizing them in cortical space, we bridge the gap between the ESI and ICA frameworks for M/EEG analysis.

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Sulaiman, N., N. S. M. Saliman, and N. Sulaiman. "Determination of potential groundwater sources using electrical resistivity imaging (ERI) in Lojing, Gua Musang." IOP Conference Series: Earth and Environmental Science 842, no. 1 (August 1, 2021): 012017. http://dx.doi.org/10.1088/1755-1315/842/1/012017.

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Mitiche, Imene, Gordon Morison, Alan Nesbitt, Michael Hughes-Narborough, Brian Stewart, and Philip Boreham. "Imaging Time Series for the Classification of EMI Discharge Sources." Sensors 18, no. 9 (September 14, 2018): 3098. http://dx.doi.org/10.3390/s18093098.

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In this work, we aim to classify a wider range of Electromagnetic Interference (EMI) discharge sources collected from new power plant sites across multiple assets. This engenders a more complex and challenging classification task. The study involves an investigation and development of new and improved feature extraction and data dimension reduction algorithms based on image processing techniques. The approach is to exploit the Gramian Angular Field technique to map the measured EMI time signals to an image, from which the significant information is extracted while removing redundancy. The image of each discharge type contains a unique fingerprint. Two feature reduction methods called the Local Binary Pattern (LBP) and the Local Phase Quantisation (LPQ) are then used within the mapped images. This provides feature vectors that can be implemented into a Random Forest (RF) classifier. The performance of a previous and the two new proposed methods, on the new database set, is compared in terms of classification accuracy, precision, recall, and F-measure. Results show that the new methods have a higher performance than the previous one, where LBP features achieve the best outcome.

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Klose, Tim, Julien Guillemoteau, François-Xavier Simon, and Jens Tronicke. "Toward subsurface magnetic permeability imaging with electromagnetic induction sensors: Sensitivity computation and reconstruction of measured data." GEOPHYSICS 83, no. 5 (September 1, 2018): E335—E345. http://dx.doi.org/10.1190/geo2017-0827.1.

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In near-surface geophysics, small portable loop-loop electromagnetic induction (EMI) sensors using harmonic sources with a constant and rather small frequency are increasingly used to investigate the electrical properties of the subsurface. For such sensors, the influence of electrical conductivity and magnetic permeability on the EMI response is well-understood. Typically, data analysis focuses on reconstructing an electrical conductivity model by inverting the out-of-phase response. However, in a variety of near-surface applications, magnetic permeability (or susceptibility) models derived from the in-phase (IP) response may provide important additional information. In view of developing a fast 3D inversion procedure of the IP response for a dense grid of measurement points, we first analyze the 3D sensitivity functions associated with a homogeneous permeable half-space. Then, we compare synthetic data computed using a linear forward-modeling method based on these sensitivity functions with synthetic data computed using full nonlinear forward-modeling methods. The results indicate the correctness and applicability of our linear forward-modeling approach. Furthermore, we determine the advantages of converting IP data into apparent permeability, which, for example, allows us to extend the applicability of the linear forward-modeling method to high-magnetic environments. Finally, we compute synthetic data with the linear theory for a model consisting of a controlled magnetic target and compare the results with field data collected with a four-configuration loop-loop EMI sensor. With this field-scale experiment, we determine that our linear forward-modeling approach can reproduce measured data with sufficiently small error, and, thus, it represents the basis for developing efficient inversion approaches.

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Peters, Jurriaan M., Damon E. Hyde, Catherine J. Chu, Merel Boom, Benoit Scherrer, Joseph R. Madsen, Scellig S. Stone, et al. "Lesion-Constrained Electrical Source Imaging." Journal of Clinical Neurophysiology 37, no. 1 (January 2020): 79–86. http://dx.doi.org/10.1097/wnp.0000000000000615.

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Halihan, Todd, Andrew Love, Mark Keppel, Meghan K. M. Dailey, Volmer Berens, and Daniel Wohling. "Evidence for groundwater mixing at Freeling Spring Group, South Australia." Hydrogeology Journal 28, no. 1 (December 4, 2019): 313–23. http://dx.doi.org/10.1007/s10040-019-02069-x.

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AbstractWater sampling at springs that are a part of the Freeling Spring Group, South Australia, was used along with electrical resistivity imaging (ERI) data to evaluate the sources and pathways for groundwater to the springs and to find evidence of mixing between the Great Artesian Basin (GAB) aquifer system (Algebuckina Sandstone, Cadna-owie Formation and lateral equivalents) and waters from the adjacent mountain block basement (MB) aquifer. Five springs and a well were used to evaluate spring chemistry; multi-electrode resistivity data were collected along three orientations over the Freeling Spring site. The resistivity data indicate three independent electrically conductive curvilinear features connected to the spring. These features are evidence of mixing at the spring vent similar to what would be predicted from traditional hydraulic flownets. The chemistry of the spring water samples indicates that the water emanating from the Freeling Spring Group is a mixture of waters from both the GAB and the MB aquifers, supporting the geophysical evidence. The data suggest mixing occurs along a fracture in the body of the MB and porous media flow in the GAB beds, but the system is dominated by the GAB flow, which provides approximately 90% of the discharge.

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Zhou, Lvhan, Qian Zhang, Xiangchun Xu, Xinming Huo, Qian Zhou, Xiaohao Wang, and Quan Yu. "Fabricating an Electrospray Ionization Chip Based on Induced Polarization and Liquid Splitting." Micromachines 12, no. 9 (August 28, 2021): 1034. http://dx.doi.org/10.3390/mi12091034.

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The coupling of the microfluidic chip to mass spectrometry (MS) has attracted considerable attention in the area of chemical and biological analysis. The most commonly used ionization technique in the chip–MS system is electrospray ionization (ESI). Traditional chip-based ESI devices mainly employ direct electrical contact between the electrode and the spray solvent. In this study, a microchip ESI source based on a novel polarization-splitting approach was developed. Specifically, the droplet in the microchannel is first polarized by the electric field and then split into two sub-droplets. In this process, the charge generated by polarization is retained in the liquid, resulting in the generation of two charged droplets with opposite polarities. Finally, when these charged droplets reach the emitter, the electrospray process is initiated and both positive and negative ions are formed from the same solution. Preliminary experimental results indicate that the coupling of this polarization-splitting ESI (PS-ESI) chip with a mass spectrometer enables conventional ESI-MS analysis of various analytes.

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Del Felice, Alessandra, Chiara Arcaro, Silvia Francesca Storti, Antonio Fiaschi, and Paolo Manganotti. "Electrical Source Imaging of Sleep Spindles." Clinical EEG and Neuroscience 45, no. 3 (October 10, 2013): 184–92. http://dx.doi.org/10.1177/1550059413497716.

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Lascano, Agustina M., Thomas Perneger, Serge Vulliemoz, Laurent Spinelli, Valentina Garibotto, Christian M. Korff, Maria I. Vargas, Christoph M. Michel, and Margitta Seeck. "Yield of MRI, high-density electric source imaging (HD-ESI), SPECT and PET in epilepsy surgery candidates." Clinical Neurophysiology 127, no. 1 (January 2016): 150–55. http://dx.doi.org/10.1016/j.clinph.2015.03.025.

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He, B. "High-resolution source imaging of brain electrical activity." IEEE Engineering in Medicine and Biology Magazine 17, no. 5 (1998): 123–29. http://dx.doi.org/10.1109/51.715496.

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Fang, Tao, Zuoting Song, Gege Zhan, Xueze Zhang, Wei Mu, Pengchao Wang, Lihua Zhang, and Xiaoyang Kang. "Decoding motor imagery tasks using ESI and hybrid feature CNN." Journal of Neural Engineering 19, no. 1 (February 1, 2022): 016022. http://dx.doi.org/10.1088/1741-2552/ac4ed0.

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Abstract Objective. Brain–computer interface (BCI) based on motor imaging electroencephalogram (MI-EEG) can be useful in a natural interaction system. In this paper, a new framework is proposed to solve the MI-EEG binary classification problem. Approach. Electrophysiological source imaging (ESI) technology is used to solve the influence of volume conduction effect and improve spatial resolution. Continuous wavelet transform and best time of interest (TOI) are combined to extract the optimal discriminant spatial-frequency features. Finally, a convolutional neural network with seven convolution layers is used to classify the features. In addition, we also validated several new data augment methods to solve the problem of small data sets and reduce network over-fitting. Main results. The model achieved an average classification accuracy of 93.2% and 95.4% on the BCI Competition III IVa and high-gamma data sets, which is better than most of the published advanced algorithms. By selecting the best TOI for each subject, the classification accuracy rate increased by about 2%. The effects of four data augment methods on the classification results were also verified. Among them, the noise addition and overlap methods are better than the other two, and the classification accuracy is improved by at least 4%. On the contrary, the rotation and flip data augment methods reduced the classification accuracy. Significance. Decoding MI tasks can benefit from combing the ESI technology and the data augment technology, which is used to solve the problem of low spatial resolution and small samples of EEG signals, respectively. Based on the results, the model proposed has higher accuracy and application potential in the task of MI-EEG binary classification.

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Morales Chacón, Lilia María, Judith González González, Martha Ríos Castillo, Sheila Berrillo Batista, Karla Batista García-Ramo, Aisel Santos Santos, Nelson Quintanal Cordero, et al. "Surgical Outcome in Extratemporal Epilepsies Based on Multimodal Pre-Surgical Evaluation and Sequential Intraoperative Electrocorticography." Behavioral Sciences 11, no. 3 (March 4, 2021): 30. http://dx.doi.org/10.3390/bs11030030.

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Objective: to present the postsurgical outcome of extratemporal epilepsy (ExTLE) patients submitted to preoperative multimodal evaluation and intraoperative sequential electrocorticography (ECoG). Subjects and methods: thirty-four pharmaco-resistant patients with lesional and non-lesional ExTLE underwent comprehensive pre-surgical evaluation including multimodal neuroimaging such as ictal and interictal perfusion single photon emission computed tomography (SPECT) scans, subtraction of ictal and interictal SPECT co-registered with magnetic resonance imaging (SISCOM) and electroencephalography (EEG) source imaging (ESI) of ictal epileptic activity. Surgical procedures were tailored by sequential intraoperative ECoG, and absolute spike frequency (ASF) was calculated in the pre- and post-resection ECoG. Postoperative clinical outcome assessment for each patient was carried out one year after surgery using Engel scores. Results: frontal and occipital resection were the most common surgical techniques applied. In addition, surgical resection encroaching upon eloquent cortex was accomplished in 41% of the ExTLE patients. Pre-surgical magnetic resonance imaging (MRI) did not indicate a distinct lesion in 47% of the cases. In the latter number of subjects, SISCOM and ESI of ictal epileptic activity made it possible to estimate the epileptogenic zone. After one- year follow up, 55.8% of the patients was categorized as Engel class I–II. In this study, there was no difference in the clinical outcome between lesional and non lesional ExTLE patients. About 43.7% of patients without lesion were also seizure- free, p = 0.15 (Fischer exact test). Patients with satisfactory seizure outcome showed lower absolute spike frequency in the pre-resection intraoperative ECoG than those with unsatisfactory seizure outcome, (Mann– Whitney U test, p = 0.005). Conclusions: this study has shown that multimodal pre-surgical evaluation based, particularly, on data from SISCOM and ESI alongside sequential intraoperative ECoG, allow seizure control to be achieved in patients with pharmacoresistant ExTLE epilepsy.

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Fan, Ya'nan, Kailiang Lu, Xiu Li, and Zhipeng Qi. "Born approximation imaging technique for electrical source multi-component TEM." Journal of Geophysics and Engineering 19, no. 3 (June 1, 2022): 418–32. http://dx.doi.org/10.1093/jge/gxac030.

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Abstract In this study, to obtain higher-resolution geoinformation in the electrical source transient electromagnetic method (TEM) interpretation, the pseudo-seismic Born approximation imaging method is applied to the vertical magnetic induction intensity ${B_z}$ and the horizontal electric field ${E_y}$, which is paralleled to the source. First, the differences between the two components are compared, and the results reveal that different components can reflect varied geological information. ${E_y}$ has a stronger signal and is more sensitive to the high-resistivity layer at a long offset, whereas ${B_z}$ has a greater relative difference in the low-resistivity layer at a short offset. The TEM field is then transformed into the pseudo-wavefield using the wavefield transformation method and the Born approximation pseudo-seismic imaging method is adopted to locate the electrical interface. After calculating the 3D model, the results indicate that the multi-component Born approximate imaging can intuitively and effectively locate the depth of the geological interface. Furthermore, the imaging results of a coal mine located in Gansu Province, China, proves that the proposed method can pinpoint the buried location of the coal goaf as well as the stratum trend. In general, the multi-component pseudo-seismic imaging technique plays a significant role in interpreting the electrical source TEM data.

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Берберова, Мария Александровна, and Виктор Иванович Балута. "ANALYSIS OF UNCERTAINTY, SIGNIFICANCE AND SENSITIVITY OF THE RESULTS OF PROBABILITY ANALYSIS OF NPP SAFETY." Информационные и математические технологии в науке и управлении, no. 1(21) (April 27, 2021): 80–93. http://dx.doi.org/10.38028/esi.2021.21.1.007.

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Атомные электростанции (АЭС) вследствие накопления в процессе эксплуатации значительных количеств радиоактивных продуктов и наличия принципиальной возможности выхода их при авариях за предусмотренные границы представляют собой источник потенциальной опасности или источник риска радиационного воздействия на персонал, население и окружающую среду. Степень радиационного риска прямо зависит от уровня безопасности АЭС, которая является одним из основных свойств АЭС, определяющих возможность их использования в качестве источников тепловой и электрической энергии. Вероятностный анализ безопасности (ВАБ) АЭС представляет собой комплексный, всесторонний системный анализ безопасности, в процессе которого разрабатываются вероятностные модели для определения конечных состояний с повреждением источников радиоактивности и конечных состояний АЭС с превышением установленных пределов по выбросам радиоактивных продуктов и радиационному воздействию на население и окружающую среду и определяются значения вероятностных показателей безопасности. Результаты ВАБ используются для качественных и количественных оценок достигнутого уровня безопасности, а также для выработки и принятия решений при проектировании и эксплуатации АЭС. Nuclear power plants (NPPs), due to the accumulation during operation of significant amounts of radioactive products and the existence of a fundamental possibility of their exit in case of accidents beyond the envisaged boundaries, represent a source of potential danger or a source of risk of radiation exposure to personnel, population and the environment. The degree of radiation risk directly depends on the level of NPP safety, which is one of the main properties of NPPs, which determine the possibility of their use as sources of thermal and electrical energy. Probabilistic safety analysis (PSA) of a nuclear power plant is a complex, comprehensive systematic safety analysis, in the process of which probabilistic models are developed to determine the end states with damage to radioactivity sources and the end states of a nuclear power plant in excess of the established limits for releases of radioactive products and radiation impact on the population and the environment. environment and the values of probabilistic safety indicators are determined. The PSA results are used for qualitative and quantitative assessments of the achieved safety level, as well as for the development and adoption of decisions in the design and operation of NPPs.

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Cui, Wenlong, Chenze Zhao, Qingqing Zhu, and Cheli Wang. "Characterization of Sulfides in Atmospheric Residue Fractions Using Selective Oxidation Followed by Fourier Transform Ion Cyclotron Resonance Mass Spectrometry." Energies 15, no. 24 (December 10, 2022): 9361. http://dx.doi.org/10.3390/en15249361.

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An improved analytical method was developed for identifying sulfide compounds from aromatic fractions in Lungu atmospheric residue (LGAR). Sulfides in residue aromatics were selectively oxidized into sulfoxides using tetrabutyl ammonium periodate (TBAP) and identified by positive-ion Electrospray Ionization Source (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Results showed that sulfides with lower polarity in LGAR aromatics could effectively ionize in ESI using this approach. Additionally, the oxidized sulfides were mainly S1 and S2 class species. The most abundant oxidation-generated sulfoxides O1S1 and O1S2 in LGAR aromatics had DBE values of 3~10 and 8~12, respectively. The S2 class species, whose condensation degree was higher than that of S1, were likely in the form of containing both cyclic sulfides and thiophenic compounds.

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Baldini, Sara, Ana Coito, Christian Korff, Karl Schaller, Margitta Seeck, Francesca Pittau, and Serge Vulliemoz. "P235 Localizing non-epileptic abnormal brain function in children using high density EEG (HDEEG): Electric source imaging (ESI) of focal slowing." Clinical Neurophysiology 128, no. 9 (September 2017): e253-e254. http://dx.doi.org/10.1016/j.clinph.2017.07.243.

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Schulz, R., M. Scherg, F. G. Woermann, and C. G. Bien. "V1. Electric source imaging (ESI) with 10–10 electrodes and individual MRI in presurgical epilepsy monitoring (BESA-Research and BESA-MRI)." Clinical Neurophysiology 126, no. 8 (August 2015): e64. http://dx.doi.org/10.1016/j.clinph.2015.04.079.

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Zhou, Yijie, Xizi Song, Zhongpeng Wang, Feng He, and Dong Ming. "Multisource Acoustoelectric Imaging With Different Current Source Features." IEEE Transactions on Instrumentation and Measurement 70 (2021): 1–9. http://dx.doi.org/10.1109/tim.2020.3021496.

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Bing, Lu, and Wei Wang. "Sparse Representation for Cardiac Electrical Activity Imaging in Magnetocardiography." Journal of Medical Imaging and Health Informatics 11, no. 7 (July 1, 2021): 2025–32. http://dx.doi.org/10.1166/jmihi.2021.3658.

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Signal sparsity has been widely discussed in communication system, cloud computing, multimedia processing and computational biology. Reconstructing the sparsely distributed current sources of the heart by means of non-invasive magnetocardiography (MCG) measurement and various optimization methods provides a new way to solve the inverse problem of the cardiac magnetic field. The problem of sparse source location of MCG is in the time series of MCG measurement caused by active sparse current source, can the spatiotemporal source be reconstructed accurately and effectively? For the above problem, the scientific contributions of the paper include: (1) A modified focal underdetermined system solver algorithm is proposed for a sparse solution, by combing with dynamic regularization factor and smoothed sparse constraint; (2) Lead field matrix is reduced by prior information of cardiac magnetic field map to reduce under-determination; (3) Spatiotemporal sources are reconstructed for non-invasive cardiac electrical activity imaging. The results of real MCG data demonstrate the effectiveness of this method for cardiac electrical activity imaging. The temporal and spatial changes of the current sources are similar to the depolarization and repolarization process of the ventricle.

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Chang-Hwan Im, Chany Lee, Hyun-Kyo Jung, Yong-Ho Lee, and S. Kuriki. "Magnetoencephalography cortical source imaging using spherical mapping." IEEE Transactions on Magnetics 41, no. 5 (May 2005): 1984–87. http://dx.doi.org/10.1109/tmag.2005.846286.

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Wang, Meng, Guizhen Lu, and Junwen Chen. "A Microwave Imaging Matrix Algorithm Based on Contrast Source." International Journal of Antennas and Propagation 2022 (June 8, 2022): 1–11. http://dx.doi.org/10.1155/2022/2594853.

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A microwave imaging matrix algorithm based on the contrast source is proposed. It is known that the contrast source and the total field change by shifting the position of the incident field. To ensure the constancy of the contrast source, this paper first proposes a novel inversion model based on the contrast source. The excitation source is located at a single fixed position, and the scattering data is obtained by measuring points evenly distributed on multiple circular layers. Secondly, a matrix algorithm based on the contrast source is proposed, which transforms the nonlinear imaging problem into a matrix operation step-by-step without iteration. The numerical simulation results show that the matrix algorithm proposed in this paper has high precision and good performance with complex imaging problems. In addition, the limitation of the proposed algorithm when inversing data with noise is also analyzed.

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Janalizadeh, Reza C., and Bijan Zakeri. "A Source-Type Best Approximation Method for Imaging Applications." IEEE Antennas and Wireless Propagation Letters 15 (2016): 1707–10. http://dx.doi.org/10.1109/lawp.2016.2527828.

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Centeno, Maria, Tim M. Tierney, Suejen Perani, Elhum A. Shamshiri, Kelly St Pier, Charlotte Wilkinson, Daniel Konn, et al. "Combined electroencephalography-functional magnetic resonance imaging and electrical source imaging improves localization of pediatric focal epilepsy." Annals of Neurology 82, no. 2 (August 2017): 278–87. http://dx.doi.org/10.1002/ana.25003.

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Painold, Annamaria, Pascal L. Faber, Patricia Milz, Eva Z. Reininghaus, Anna K. Holl, Martin Letmaier, Roberto D. Pascual-Marqui, Bernd Reininghaus, Hans-Peter Kapfhammer, and Dietrich Lehmann. "Brain electrical source imaging in manic and depressive episodes of bipolar disorder." Bipolar Disorders 16, no. 7 (March 17, 2014): 690–702. http://dx.doi.org/10.1111/bdi.12198.

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Birot, Gwénael, Laurent Spinelli, Serge Vulliémoz, Pierre Mégevand, Denis Brunet, Margitta Seeck, and Christoph M. Michel. "Head model and electrical source imaging: A study of 38 epileptic patients." NeuroImage: Clinical 5 (2014): 77–83. http://dx.doi.org/10.1016/j.nicl.2014.06.005.

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Koessler, L., C. Abdallah, E. Rikir, M. Gavaret, and L. Maillard. "Localizing value of interictal electrical source imaging: Who are the best candidates?" Neurophysiologie Clinique 49, no. 3 (June 2019): 185. http://dx.doi.org/10.1016/j.neucli.2019.05.011.

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Toscano, Gianpaolo, Margherita Carboni, Maria Rubega, Laurent Spinelli, Francesca Pittau, Andrea Bartoli, Shahan Momjian, et al. "Visual analysis of high density EEG: As good as electrical source imaging?" Clinical Neurophysiology Practice 5 (2020): 16–22. http://dx.doi.org/10.1016/j.cnp.2019.09.002.

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Qiu, Ping, and Ke Wang. "Optimal compression in synchronised time‐lens source for CRS imaging." Electronics Letters 50, no. 3 (January 2014): 148–49. http://dx.doi.org/10.1049/el.2013.3146.

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Zápražný, Zdenko, Dušan Korytár, František Dubecký, Vladimír Áč, Zbigniew Stachura, Janusz Lekki, Jakub Bielicky, and Ján Mudroň. "Experience with Imaging by Using of Microfocus X-Ray Source." Journal of Electrical Engineering 61, no. 5 (September 1, 2010): 287–90. http://dx.doi.org/10.2478/v10187-010-0042-3.

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Experience with Imaging by Using of Microfocus X-Ray SourceIn this paper we present the current work and experience with using microfocus x-ray generator and commercial CCD camera for x-ray imaging purpose. There is a need in laboratories for the development of imaging methods approaching synchrotron radiation sources, where the brilliance of radiation is on very high-level. Generally, there is no continuous access to synchrotron facilities. Several synchrotron radiation laboratories allocate the access via a proposal system. Thus the time for synchrotron radiation experiments seldom exceeds more than 1-2 weeks per year, which restricts its application to a few selected experiments. Even in future, the routine characterization of samples will be performed mainly at the experimenters home laboratories [10]. In this contribution we show that with the present set-up it is possible to achieve the spatial resolution down to μm and with the appropriate geometry a phase contrast images are observable.

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Luan, F., J. H. Choi, and H. K. Jung. "Measurement of bio-electromagnetic source signal via subspace decomposition imaging." Electronics Letters 48, no. 7 (2012): 364. http://dx.doi.org/10.1049/el.2011.3985.

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Li Miao, 黎淼, 肖沙里 Xiao Shali, 张流强 Zhang Liuqiang, 曹玉琳 Cao Yulin, 陈宇晓 Chen Yuxiao, 沈敏 Shen Min, and 王玺 Wang Xi. "Gamma source imaging based on pixellated CdZnTe detection." High Power Laser and Particle Beams 22, no. 9 (2010): 2165–60. http://dx.doi.org/10.3788/hplpb20102209.2165.

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Journal articles on the topic 'Electrical source imaging (ESI)'

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