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Ultrafast pulse-dilation framing camera and its application for time-resolved X-ray diagnostic
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作者 Hou-Zhi Cai Qiu-Yan Luo +10 位作者 Kai-Xuan Lin Xuan Deng Jun-Kai Liu Kai-Zhi Yang Dong Wang Jia-Jie Chen Jia-Heng Wang Jing-Hua Long Li-Hong Niu Yun-Fei Lei Jin-Yuan Liu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第7期101-114,共14页
An ultrafast framing camera with a pulse-dilation device,a microchannel plate(MCP)imager,and an electronic imaging system were reported.The camera achieved a temporal resolution of 10 ps by using a pulse-dilation devi... An ultrafast framing camera with a pulse-dilation device,a microchannel plate(MCP)imager,and an electronic imaging system were reported.The camera achieved a temporal resolution of 10 ps by using a pulse-dilation device and gated MCP imager,and a spatial resolution of 100μm by using an electronic imaging system comprising combined magnetic lenses.The spatial resolution characteristics of the camera were studied both theoretically and experimentally.The results showed that the camera with combined magnetic lenses reduced the field curvature and acquired a larger working area.A working area with a diameter of 53 mm was created by applying four magnetic lenses to the camera.Furthermore,the camera was used to detect the X-rays produced by the laser-targeting device.The diagnostic results indicated that the width of the X-ray pulse was approximately 18 ps. 展开更多
关键词 Inertial confinement fusion Plasma diagnostics Framing camera Combined lenses Pulse-dilation
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High-resolution x-ray monochromatic imaging for laser plasma diagnostics based on toroidal crystal 被引量:2
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作者 司昊轩 董佳钦 +3 位作者 方智恒 蒋励 伊圣振 王占山 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第1期181-186,共6页
Monochromatic x-ray imaging is an essential method for plasma diagnostics related to density information.Large-field high-resolution monochromatic imaging of a He-like iron(Fe XXV)Kαcharacteristic line(6.701 keV)for ... Monochromatic x-ray imaging is an essential method for plasma diagnostics related to density information.Large-field high-resolution monochromatic imaging of a He-like iron(Fe XXV)Kαcharacteristic line(6.701 keV)for laser plasma diagnostics was achieved using a developed toroidal crystal x-ray imager.A high-index crystal orientation Ge(531)wafer with a Bragg angle of 75.37°and the toroidal substrate were selected to obtain sufficient diffraction efficiency and compensate for astigmatism under oblique incidence.A precise offline assembly method of the toroidal crystal imager based on energy substitution was proposed,and a spatial resolution of 3-7μm was obtained by toroidal crystal imaging of a 600 line-pairs/inch Au grid within an object field of view larger than 1.0 mm.The toroidal crystal x-ray imager has been successfully tested via side-on backlight imaging experiments of the sinusoidal modulation target and a 1000 line-pairs/inch Au grid with a linewidth of 5μm using an online alignment method based on dual positioning balls to indicate the target and backlighter.This paper describes the optical design,adjustment method,and experimental results of a toroidal crystal system in a laboratory and laser facility. 展开更多
关键词 laser plasma diagnostics toroidal crystal monochromatic x-ray imaging
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Evaluation of Entrance Skin Dose from Paediatric Diagnostic X-Ray Examination
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作者 Moromoke Oluwayemisi Adelayi Oladele Samuel Ajayi 《Open Journal of Radiology》 2023年第1期26-33,共8页
As children are prone to be more radiosensitive than adults, it is imperative to assess the Entrance Skin Doses (ESDs) for patients being examined by X-rays, in order to ensure the optimization of dose while consideri... As children are prone to be more radiosensitive than adults, it is imperative to assess the Entrance Skin Doses (ESDs) for patients being examined by X-rays, in order to ensure the optimization of dose while considering a number of other fickles. The ESD received by 50 paediatrics (aged 1-13 years) undergoing 8 types of X-ray examinations were measured at Federal Teaching Hospital, Ido-Ekiti, Ekiti, Nigeria, within a period of February 2019 to March 2020 using thermoluminescent dosimeters. The mean ± SD of ESDs were 0.85 ± 0.32, 2.04 ± 0.75, 0.60 ± 0.07, 0.62 ± 0.22, 0.57 ± 0.24, 1.75 ± 0.76, 0.93 ± 0.31 and 0.63 ± 0.06 mGy for Chest, Skull, Hand, Forearm, Knee, Abdomen, Leg and Feet, respectively. The mean ESDs were found to be within the recommended reference dose in all examinations, except for the Chest examination which was higher. The data obtained in this study will serve as existing data in Nigeria for future research works, as it would assist in optimizing dose to patients, especially the paediatrics. 展开更多
关键词 Entrance Skin Dose PAEDIATRICS x-rays
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Soft x-ray Diode-array Diagnostic System for HT-7 Superconducting Tokamak 被引量:1
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作者 胡立群 卫明生 +2 位作者 凌必利 方自深 曾立 《Plasma Science and Technology》 SCIE EI CAS CSCD 2000年第6期515-521,共7页
A diagnostic system of soft x-ray diode-array was set up for HT-7 superconducting tokamak. The system consists of two slot-aperture cameras and is capable of measuring the soft x-ray emission from the plasma on HT-7 d... A diagnostic system of soft x-ray diode-array was set up for HT-7 superconducting tokamak. The system consists of two slot-aperture cameras and is capable of measuring the soft x-ray emission from the plasma on HT-7 device with a high resolution in space and a high response in time. Both cameras, located separately in a horizontal port and a vertical port each with thirty-seven detectors of An-Si surface-barrier diode (SBD) can view the same toroidal cross-section of the plasma from different poloidal chords. In this paper, the structure, principle and performance of the diagnostic system are described and some experimental results observed are presented. 展开更多
关键词 LHCD Soft x-ray Diode-array diagnostic System for HT-7 Superconducting Tokamak HT SBD MODE
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Design of Time-Resolved Shifted Dual Transmission Grating Spectrometer for the X-Ray Spectrum Diagnostics 被引量:1
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作者 王保清 易涛 +6 位作者 王传珂 朱效立 李廷帅 李晋 刘慎业 江少恩 丁永坤 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第7期781-785,共5页
A new time-resolved shifted dual transmission grating spectrometer (SDTGS) is designed and fabricated in this work. This SDTGS uses a new shifted dual transmission grating (SDTG) as its dispersive component, which... A new time-resolved shifted dual transmission grating spectrometer (SDTGS) is designed and fabricated in this work. This SDTGS uses a new shifted dual transmission grating (SDTG) as its dispersive component, which has two sub transmission gratings with different line densities, of 2000 lines/mm and 5000 lines/mm. The axes of the two sub transmission gratings in SDTG are horizontally and vertically shifted a certain distance to measure a broad range of 0.1-5 keV time-resolved X-ray spectra. The SDTG has been calibrated with a soft X-ray beam of the synchrotron radiation facility and its diffraction efficiency is also measured. The designed SDTGS can take full use of the space on a record panel and improve the precision for measuring spatial and temporal spectrum simultaneously. It will be a promising application for accurate diagnosis of the soft X-ray spectrum in inertial confinement fusion. 展开更多
关键词 shifted dual transmission grating spectrometer GRATING x-ray spectra diag-nosis of the soft x-ray spectrum
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Self Consistent Calibration of Detectors and Sources for Hard and Soft X-Ray Diagnostics
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作者 Danilo Pacella Afra Romano +3 位作者 Seung Hun Lee Federica Causa Lori Gabellieri Wonho Choe 《Modern Instrumentation》 2014年第3期13-23,共11页
X-Ray sources, detectors and optical components are now used in a wide range of applications. What is crucial is the absolute calibration of such devices to permit a quantitative assessment of the system under study. ... X-Ray sources, detectors and optical components are now used in a wide range of applications. What is crucial is the absolute calibration of such devices to permit a quantitative assessment of the system under study. A new X-ray laboratory has been built in Frascati (ENEA) to develop diagnostics for nuclear fusion experiments and study applications of these X-ray techniques in other domains, like new material science, non destructive tests and so on. An in-house developed selfconsistent calibration procedure is described that permits the absolute calibration of sources (X-ray emitted fluxes) and detectors (detection efficiencies) as function of the X-ray photon energy, in the range 2 - 120 keV. The calibration procedure involves the use of an in-house developed code that also predicts the spectral response of any detector in any experimental condition that can be setup in the laboratory. The procedure has been then applied for the calibration and characterisation of gas and solid state imaging detectors, such as Medipix-2, GEM gas detector, CCD camera, Cd-Te C-MOS imager, demonstrating the versatility of the method developed here. 展开更多
关键词 x-ray Detector x-ray Source ABSOLUTE CALIBRATION Plasma Physics diagnosticS
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Combined molybdenum target X-ray and magnetic resonance imaging examinations improve breast cancer diagnostic efficacy 被引量:14
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作者 Wen-Quan Gu Sun-Mei Cai +3 位作者 Wei-Dong Liu Qi Zhang Ying Shi Li-Juan Du 《World Journal of Clinical Cases》 SCIE 2022年第2期485-491,共7页
BACKGROUND Early-stage breast cancer patients often lack specific clinical manifestations,making diagnosis difficult.Molybdenum target X-ray and magnetic resonance imaging(MRI)examinations both have their own advantag... BACKGROUND Early-stage breast cancer patients often lack specific clinical manifestations,making diagnosis difficult.Molybdenum target X-ray and magnetic resonance imaging(MRI)examinations both have their own advantages.Thus,a combined examination methodology may improve early breast cancer diagnoses.AIM To explore the combined diagnostic efficacy of molybdenum target X-ray and MRI examinations in breast cancer.METHODS Patients diagnosed with breast cancer at our hospital from March 2019 to April 2021 were recruited,as were the same number of patients during the same period with benign breast tumors.Both groups underwent molybdenum target X-ray and MRI examinations,and diagnoses were given based on each exam.The single(i.e.,X-ray or MRI)and combined(i.e.,using both methods)diagnoses were counted,and the MRI-related examination parameters(e.g.,T-wave peak,peak and early enhancement rates,and apparent diffusion coefficient)were compared between the groups.RESULTS In total,63 breast cancer patients and 63 benign breast tumor patients were recruited.MRI detected 53 breast cancer cases and 61 benign breast tumor cases.Molybdenum target X-ray detected 50 breast cancer cases and 60 benign breast tumor cases.The combined methodology detected 61 breast cancer cases and 61 benign breast tumor cases.The sensitivity(96.83%)and accuracy(96.83%)of the combined methodology were higher than single-method MRI(84.13%and 90.48%,respectively)and molybdenum target X-ray(79.37%and 87.30%,respectively)(P<0.05).The combined methodology specificity(96.83%)did not differ from singlemethod MRI(96.83%)or molybdenum target X-ray(95.24%)(P>0.05).The Twave peak(169.43±32.05)and apparent diffusion coefficient(1.01±0.23)were lower in the breast cancer group than in the benign tumor group(228.86±46.51 and 1.41±0.35,respectively).However,the peak enhancement rate(1.08±0.24)and early enhancement rate(1.07±0.26)were significantly higher in the breast cancer group than in the benign tumor group(0.83±0.19 and 0.75±0.19,respectively)(P<0.05).CONCLUSION Combined molybdenum target X-ray and MRI examinations for diagnosing breast cancer improved the diagnostic sensitivity and accuracy,minimizing the missedand misdiagnoses risks and promoting timely treatment intervention. 展开更多
关键词 MOLYBDENUM x-rays Magnetic resonance imaging Breast neoplasms Early diagnosis RADIOLOGY
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Diagnostic Reference Level in Frontal Chest X-Ray in Western Côte d’Ivoire 被引量:2
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作者 Issa Konate George A. Monnehan +3 位作者 Douo B. L. H. Gogon Tekpo P. A. Dali Aka A. Koua Koudou Djagouri 《World Journal of Nuclear Science and Technology》 2019年第4期147-158,共12页
Our study aims to determine diagnostic reference levels (DRL) for chest front examination in postero anterior (PA) for optimizing patient entrance surface dose (ESD) and dose-area product (DAP) of patients in west of ... Our study aims to determine diagnostic reference levels (DRL) for chest front examination in postero anterior (PA) for optimizing patient entrance surface dose (ESD) and dose-area product (DAP) of patients in west of C&ocirc;te d’Ivoire. 90 patients from three hospitals undergoing conventional radiology were considered. The ESD and DAP for each patient were obtained during chest radiography (PA) examination. The measurements were performed with the device call Dose-Area Product-meter (DAP-meter) with brand Diamentor M4-KDK, type 11017. The DRL were obtained in applying the 75th percentile statistical method to the obtained ESD and DAP. The obtained DRL in ESD for chest radiography for all rooms is 0.40 mGy and in DAP is 54.85 cGy&middot;cm2. Our DRL for ESD is higher than those obtained in Abidjan District and in other countries like UK and Cameroon. Our DRL for DAP is higher than those from Abidjan and all other countries for which a similar study was made. The comparison of these values to those from Abidjan and other countries, shows us that radiology technicians can make efforts to choose radiological parameters to reduce ESD. They must use convenable the X-rays tube to reduce DAP by reducing the patient exposure surface. 展开更多
关键词 Conventional RADIOLOGY ENTRANCE Surface-Dose Dose-Area-Product Dose-Area Product-Meter diagnostic REFERENCE Levels
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Diagnostic Value of the Thoracic Ultrasonography Compared to Conventional Chest X-Rays in Pneumonia for Children between 0 to 15 Years: Case Study in Two Hospitals in Yaoundé 被引量:2
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作者 Seme Engoumou Ambroise Merci Mbede Maggy +3 位作者 Awana Armel Philippe Bilounga Ndengue Priscille Edith Onguene Julienne Zeh Odile Fernande 《Open Journal of Radiology》 2019年第1期10-19,共10页
Introduction: The diagnosis of pneumonia is usually made based on clinical manifestations and chest X-ray. The use of ultrasound in detecting pulmonary diseases in general, and especially consolidation syndrome has be... Introduction: The diagnosis of pneumonia is usually made based on clinical manifestations and chest X-ray. The use of ultrasound in detecting pulmonary diseases in general, and especially consolidation syndrome has been demonstrated. The objective of this study was to determine the accuracy of thoracic ultrasound compared to chest X-ray in the diagnosis of infectious pneumonia in children. Methods: Children between 0 to 15 years were included in our study. The lung ultrasound results obtained were compared with those of the chest X-ray used as the reference. Our data were introduced into the EpiInfo 3.5.4 software and analyzed with the EpiInfo 3.5.4 and IBMSPSS Statistics version 20.0 softwares. Microsoft Office Excel 2016 was used to produce Charts. Continuous quantitative variables were presented. Cohen’s Kappa concordance test was applied with confidence interval of 95%. Results: 52 children were enrolled in the study. In imaging, the dominant sign was consolidation syndrome (75.0%) of cases by chest radiography, and in 78.8% of cases by lung ultrasound (p Conclusion: Our study demonstrated that lung echography is a non-ionizing and reliable tool in the diagnosis of childhood’s pneumonia. 展开更多
关键词 LUNG Ultrasound CHEST x-ray PNEUMONIA CHILDREN Yaoundé Cameroon
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Diagnostic delay in inflammatory bowel diseases in a German population 被引量:2
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作者 Elisabeth Blüthner Annalena Dehe +11 位作者 Carsten Büning Britta Siegmund Matthias Prager Jochen Maul Alexander Krannich Jan Preiß Bertram Wiedenmann Florian Rieder Raneem Khedraki Frank Tacke Andreas Sturm Anja Schirbel 《World Journal of Gastroenterology》 SCIE CAS 2024年第29期3465-3478,共14页
BACKGROUND Early diagnosis is key to prevent bowel damage in inflammatory bowel disease(IBD).Risk factor analyses linked with delayed diagnosis in European IBD patients are scarce and no data in German IBD patients ex... BACKGROUND Early diagnosis is key to prevent bowel damage in inflammatory bowel disease(IBD).Risk factor analyses linked with delayed diagnosis in European IBD patients are scarce and no data in German IBD patients exists.AIM To identify risk factors leading to prolonged diagnostic time in a German IBD cohort.METHODS Between 2012 and 2022,430 IBD patients from four Berlin hospitals were enrolled in a prospective study and asked to complete a 16-item questionnaire to determine features of the path leading to IBD diagnosis.Total diagnostic time was defined as the time from symptom onset to consulting a physician(patient waiting time)and from first consultation to IBD diagnosis(physician diagnostic time).Univariate and multivariate analyses were performed to identify risk factors for each time period.RESULTS The total diagnostic time was significantly longer in Crohn’s disease(CD)compared to ulcerative colitis(UC)patients(12.0 vs 4.0 mo;P<0.001),mainly due to increased physician diagnostic time(5.5 vs 1.0 mo;P<0.001).In a multivariate analysis,the predominant symptoms diarrhea(P=0.012)and skin lesions(P=0.028)as well as performed gastroscopy(P=0.042)were associated with longer physician diagnostic time in CD patients.In UC,fever was correlated(P=0.020)with shorter physician diagnostic time,while fatigue(P=0.011)and positive family history(P=0.046)were correlated with longer physician diagnostic time.CONCLUSION We demonstrated that CD patients compared to UC are at risk of long diagnostic delay.Future efforts should focus on shortening the diagnostic delay for a better outcome in these patients. 展开更多
关键词 diagnostic time diagnostic delay Crohn’s disease Ulcerative colitis GERMANY
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A portable X-pinch design for x-ray diagnostics of warm dense matter
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作者 J.Strucka J.W.D.Halliday +13 位作者 T.Gheorghiu H.Horton B.Krawczyk P.Moloney S.Parker G.Rowland N.Schwartz S.Stanislaus S.Theocharous C.Wilson Z.Zhao T.A.Shelkovenko S.A.Pikuz S.N.Bland 《Matter and Radiation at Extremes》 SCIE EI CAS CSCD 2022年第1期53-63,共11页
We describe the design and x-ray emission properties(temporal,spatial,and spectral)of Dry Pinch I,a portable X-pinch driver developed at Imperial College London.Dry Pinch I is a direct capacitor discharge device,30033... We describe the design and x-ray emission properties(temporal,spatial,and spectral)of Dry Pinch I,a portable X-pinch driver developed at Imperial College London.Dry Pinch I is a direct capacitor discharge device,30033003700 mm3 in size and∼50 kg in mass,that can be used as an external driver for x-ray diagnostics in high-energy-density physics experiments.Among key findings,the device is shown to reliably produce 1.1±0.3 ns long x-ray bursts that couple∼50 mJ of energy into photon energies from 1 to 10 keV.The average shot-to-shot jitter of these bursts is found to be 10±4.6 ns using a combination of x-ray and current diagnostics.The spatial extent of the x-ray hot spot from which the radiation emanates agrees with previously published results for X-pinches-suggesting a spot size of 10±6μm in the soft energy region(1–10 keV)and 190±100μm in the hard energy region(>10 keV).These characteristics mean that Dry Pinch I is ideally suited for use as a probe in experiments driven in the laboratory or at external facilities when more conventional sources of probing radiation are not available.At the same time,this is also the first detailed investigation of an X-pinch operating reliably at current rise rates of less than 1 kA/ns. 展开更多
关键词 energy diagnosticS PINCH
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Soft X-ray PHA Diagnostic for the Electron Ternperature Measurements on EAST
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作者 许平 林士耀 +2 位作者 胡立群 段艳敏 张继宗 《Plasma Science and Technology》 SCIE EI CAS CSCD 2009年第4期468-471,共4页
Two soft X-ray pulse height analysis (PHA) systems, based on silicon drift detec- tor (SDD), were established on the experimental advanced superconducting tokamak (EAST) to measure spectrum of soft X-ray emissio... Two soft X-ray pulse height analysis (PHA) systems, based on silicon drift detec- tor (SDD), were established on the experimental advanced superconducting tokamak (EAST) to measure spectrum of soft X-ray emission. In this paper, the soft X-ray PHA systems on EAST are introduced and some experimental results of electron temperature in EAST obtained from the soft X-ray PHA diagnostic are presented. 展开更多
关键词 EAST soft x-ray PHA silicon driR detector (SDD) electron temperature(To)
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Performance of Large Area Thin-Film CdTe Detector in Diagnostic X-Ray Imaging
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作者 Diana Shvydka , Xiance Jin E. Ishmael Parsai 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2013年第3期98-109,共12页
Significant advancement in thin-film cadmium telluride (CdTe) deposition techniques in recent years has made this material attractive for the development of low-cost large area detector. Here we evaluate the intrinsic... Significant advancement in thin-film cadmium telluride (CdTe) deposition techniques in recent years has made this material attractive for the development of low-cost large area detector. Here we evaluate the intrinsic performance of the detector for a range of energies relevant to diagnostic imaging applications, such as fluoroscopy. The input x-ray spectra for a set of tube potentials ranging from 70 to 140 kVp were computed with the tungsten anode spectral model using interpolating polynomials (TASMIP) based on the measured output of our diagnostic x-ray simulator. Frequency-dependent detector performance analysis was conducted through Monte Carlo simulations of energy deposition within the detector. Intrinsic modulation transfer functions (MTF), noise power spectra (NPS), and detective quantum efficiencies (DQE) were computed for a set of CdTe detectors of varying thickness, from 100 to 1000 μm. MTF behavior at higher frequencies was affected by thickness and input energy, NPS increased with film thickness and energy, and the resultant DQE(f) decreased with increasing the input energy, but increased with the thickness of the detector. We found that the optimal thickness of CdTe under diagnostic x-ray beam is in the range of 300 to 600 μm. Physical properties of CdTe, such as the high atomic number and density, used in direct detection configuration, together with the recently established thin-film manufacturing techniques makes this technology a promising photoconductor for large area diagnostic flat panel imaging. 展开更多
关键词 MONTE Carlo CDTE DETECTOR PHOTOVOLTAIC THIN Film TASMIP DQE x-ray Imaging
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A synthetic diagnostics platform for microwave imaging diagnostics in tokamaks
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作者 李子涵 杨尚川 +5 位作者 徐新航 张立夫 渠承明 李诚普 庄革 谢锦林 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第3期38-45,共8页
Interpreting experimental diagnostics data in tokamaks,while considering non-ideal effects,is challenging due to the complexity of plasmas.To address this challenge,a general synthetic diagnostics(GSD)platform has bee... Interpreting experimental diagnostics data in tokamaks,while considering non-ideal effects,is challenging due to the complexity of plasmas.To address this challenge,a general synthetic diagnostics(GSD)platform has been established that facilitates microwave imaging reflectometry and electron cyclotron emission imaging.This platform utilizes plasma profiles as input and incorporates the finite-difference time domain,ray tracing and the radiative transfer equation to calculate the propagation of plasma spontaneous radiation and the external electromagnetic field in plasmas.Benchmark tests for classical cases have been conducted to verify the accuracy of every core module in the GSD platform.Finally,2D imaging of a typical electron temperature distribution is reproduced by this platform and the results are consistent with the given real experimental data.This platform also has the potential to be extended to 3D electromagnetic field simulations and other microwave diagnostics such as cross-polarization scattering. 展开更多
关键词 synthetic diagnostics tokamak plasmas microwave imaging diagnostics microwave imaging reflectometer electron cyclotron emission imaging
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Addressing diagnostic delays in inflammatory bowel diseases in Germany
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作者 Shi-Yan Zhang Yin Lin 《World Journal of Gastroenterology》 SCIE CAS 2024年第41期4484-4489,共6页
Inflammatory bowel diseases(IBDs),including Crohn's disease(CD)and ulcerative colitis,are chronic inflammatory conditions of the gastrointestinal tract that necessitate timely diagnosis to prevent complications an... Inflammatory bowel diseases(IBDs),including Crohn's disease(CD)and ulcerative colitis,are chronic inflammatory conditions of the gastrointestinal tract that necessitate timely diagnosis to prevent complications and improve patient outcomes.Despite advancements in medical knowledge and diagnostic techniques,significant diagnostic delays persist,particularly in CD.The study by Blüthner et al,published in the World Journal of Gastroenterology,elucidates the diagnostic delays experienced by German patients with IBD and identifies key risk factors contributing to these delays. 展开更多
关键词 Inflammatory bowel disease Crohn's disease Ulcerative colitis diagnostic delay Physician diagnostic time Risk factors Early diagnosis Patient outcomes
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Most Intense X-Ray Lines of the Helium Isoelectronic Sequence for Plasmas Diagnostic
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作者 Ibrahima Sakho 《Journal of Modern Physics》 2020年第4期487-501,共15页
We report accurate wavelengths for the three most intense lines (resonance line: 1s2 1S0 - 1s2p 1P1, intercombination line: 1s2 1S0 - 1s2p 3P1 and forbidden line: 1s2 1S0 - 1s2s 3S1) along with wavelengths for the 1s2... We report accurate wavelengths for the three most intense lines (resonance line: 1s2 1S0 - 1s2p 1P1, intercombination line: 1s2 1S0 - 1s2p 3P1 and forbidden line: 1s2 1S0 - 1s2s 3S1) along with wavelengths for the 1s2 1S0 - 1snp1P1 and 1S0 - 1snp3P2 (2 ≤ n ≤ 25) transitions in He-like systems (Z = 2 – 13). The first spectral lines that belong to the above transitions are established in the framework of the Screening Constant per Unit Nuclear Charge method. The results obtained agree excellently with various experimental and theoretical literature data. The uncertainties in wavelengths between the present calculations and the available literature data are less than 0.004&Aring;. A host of new data listed in this paper may be of interest in astrophysical and laboratory plasmas diagnostic. 展开更多
关键词 HE-LIKE Systems SEMI-EMPIRICAL Screening Constant Per Unit Nuclear Charge Excited States x-ray Spectra
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Synchrotron X-ray diagnostics of cutoff shape of nonthermal electron spectrum at young supernova remnants
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作者 Ryo Yamazaki Yutaka Ohira +1 位作者 Makoto Sawada Aya Bamba 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第2期165-178,共14页
Synchrotron X-rays can be a useful tool to investigate electron accelera- tion at young supemova remnants (SNRs). At present, since the magnetic field con- figuration around the shocks of SNRs is uncertain, it is no... Synchrotron X-rays can be a useful tool to investigate electron accelera- tion at young supemova remnants (SNRs). At present, since the magnetic field con- figuration around the shocks of SNRs is uncertain, it is not clear whether electron acceleration is limited by SNR age, synchrotron cooling, or even escape from the ac- celeration region. We study whether the acceleration mechanism can be constrained by the cutoff shape of the electron spectrum around the maximum energy. We derive analytical formulae of the cutoff shape in each case where the maximum electron en- ergy is determined by SNR age, synchrotron cooling and escape from the shock. They are related to the energy dependence of the electron diffusion coefficient. Next, we discuss whether information on the cutoff shape can be provided by observations in the near future which will simply give the photon indices and the flux ratios in the soft and hard X-ray bands. We find that if the power-law index of the electron spectrum is independently determined by other observations, then we can constrain the cutoff shape by comparing theoretical predictions of the photon indices and/or the flux ratios with observed data which will be measured by NuSTAR and/or ASTRO-H. Such study is helpful in understanding the acceleration mechanism. In particular, it will supply another independent constraint on the magnetic field strength around the shocks of SNRs. 展开更多
关键词 acceleration of particles -- ISM: cosmic rays -- ISM: supernova rem-nants -- turbulence -- x-rays: ISM
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Stage at diagnosis of colorectal cancer through diagnostic route:Who should be screened? 被引量:9
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作者 Nobukazu Agatsuma Takahiro Utsumi +11 位作者 Yoshitaka Nishikawa Takahiro Horimatsu Takeshi Seta Yukitaka Yamashita Yukari Tanaka Takahiro Inoue Yuki Nakanishi Takahiro Shimizu Mikako Ohno Akane Fukushima Takeo Nakayama Hiroshi Seno 《World Journal of Gastroenterology》 SCIE CAS 2024年第10期1368-1376,共9页
BACKGROUND Colorectal cancer(CRC)is a global health concern,with advanced-stage diagnoses contributing to poor prognoses.The efficacy of CRC screening has been well-established;nevertheless,a significant proportion of... BACKGROUND Colorectal cancer(CRC)is a global health concern,with advanced-stage diagnoses contributing to poor prognoses.The efficacy of CRC screening has been well-established;nevertheless,a significant proportion of patients remain unscreened,with>70%of cases diagnosed outside screening.Although identifying specific subgroups for whom CRC screening should be particularly recommended is crucial owing to limited resources,the association between the diagnostic routes and identification of these subgroups has been less appreciated.In the Japanese cancer registry,the diagnostic routes for groups discovered outside of screening are primarily categorized into those with comorbidities found during hospital visits and those with CRC-related symptoms.AIM To clarify the stage at CRC diagnosis based on diagnostic routes.METHODS We conducted a retrospective observational study using a cancer registry of patients with CRC between January 2016 and December 2019 at two hospitals.The diagnostic routes were primarily classified into three groups:Cancer screening,follow-up,and symptomatic.The early-stage was defined as Stages 0 or I.Multivariate and univariate logistic regressions were exploited to determine the odds of early-stage diagnosis in the symptomatic and cancer screening groups,referencing the follow-up group.The adjusted covariates were age,sex,and tumor location.RESULTS Of the 2083 patients,715(34.4%),1064(51.1%),and 304(14.6%)belonged to the follow-up,symptomatic,and cancer screening groups,respectively.Among the 2083 patients,CRCs diagnosed at an early stage were 57.3%(410 of 715),23.9%(254 of 1064),and 59.5%(181 of 304)in the follow-up,symptomatic,and cancer screening groups,respectively.The symptomatic group exhibited a lower likelihood of early-stage diagnosis than the follow-up group[P<0.001,adjusted odds ratio(aOR),0.23;95%confidence interval(95%CI):0.19-0.29].The likelihood of diagnosis at an early stage was similar between the follow-up and cancer screening groups(P=0.493,aOR for early-stage diagnosis in the cancer screening group vs follow-up group=1.11;95%CI=0.82-1.49).CONCLUSION CRCs detected during hospital visits for comorbidities were diagnosed earlier,similar to cancer screening.CRC screening should be recommended,particularly for patients without periodical hospital visits for comorbidities. 展开更多
关键词 Colorectal neoplasms Cancer registry diagnostic route Cancer screening Stage at diagnosis
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Clinical diagnostic advances in intestinal anastomotic techniques:Hand suturing,stapling,and compression devices 被引量:1
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作者 Ah Young Lee Joo Young Cho 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第5期1231-1234,共4页
The development of intestinal anastomosis techniques,including hand suturing,stapling,and compression anastomoses,has been a significant advancement in surgical practice.These methods aim to prevent leakage and minimi... The development of intestinal anastomosis techniques,including hand suturing,stapling,and compression anastomoses,has been a significant advancement in surgical practice.These methods aim to prevent leakage and minimize tissue fibrosis,which can lead to stricture formation.The healing process involves various phases:hemostasis and inflammation,proliferation,and remodeling.Mechanical staplers and sutures can cause inflammation and fibrosis due to the release of profibrotic chemokines.Compression anastomosis devices,including those made of nickel-titanium alloy,offer a minimally invasive option for various surgical challenges and have shown safety and efficacy.However,despite advancements,anastomotic techniques are evaluated based on leakage risk,with complications being a primary concern.Newer devices like Magnamosis use magnetic rings for compression anastomosis,demonstrating greater strength and patency compared to stapling.Magnetic technology is also being explored for other medical treatments.While there are promising results,particularly in animal models,the realworld application in humans is limited,and further research is needed to assess their safety and practicality. 展开更多
关键词 ANASTOMOSES diagnostic advances Anastomotic techniques Technique Intestine
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Exploring non-invasive diagnostics for metabolic dysfunctionassociated fatty liver disease 被引量:1
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作者 Biao Qu Zheng Li 《World Journal of Gastroenterology》 SCIE CAS 2024年第28期3447-3451,共5页
The population with metabolic dysfunction-associated fatty liver disease(MAFLD)is increasingly common worldwide.Identification of people at risk of progression to advanced stages is necessary to timely offer intervent... The population with metabolic dysfunction-associated fatty liver disease(MAFLD)is increasingly common worldwide.Identification of people at risk of progression to advanced stages is necessary to timely offer interventions and appropriate care.Liver biopsy is currently considered the gold standard for the diagnosis and staging of MAFLD,but it has associated risks and limitations.This has spurred the exploration of non-invasive diagnostics for MAFLD,especially for steatohepatitis and fibrosis.These non-invasive approaches mostly include biomarkers and algorithms derived from anthropometric measurements,serum tests,imaging or stool metagenome profiling.However,they still need rigorous and widespread clinical validation for the diagnostic performance. 展开更多
关键词 Metabolic dysfunction-associated fatty liver disease Non-invasive diagnostics Circulating biomarkers Imaging biomarkers Stool microbial biomarkers
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