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A Narrowband Burst from FRB 20190520B Simultaneously Observed by FAST and Parkes
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作者 Yuhao Zhu Chenhui Niu +8 位作者 Shi Dai Di Li Pei Wang Yi Feng Jingwen Wu Yongkun Zhang Xianghan Cui Junshuo Zhang Jinhuang Cao 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第10期144-151,共8页
Fast radio bursts(FRBs)are short-duration radio transients with mysterious origins.Since their uncertainty,there are very few FRBs observed by different instruments simultaneously.This study presents a detailed analys... Fast radio bursts(FRBs)are short-duration radio transients with mysterious origins.Since their uncertainty,there are very few FRBs observed by different instruments simultaneously.This study presents a detailed analysis of a burst from FRB 20190520B observed by FAST and Parkes at the same time.The spectrum of this individual burst ended at the upper limit of the FAST frequency band and was simultaneously detected by the Parkes telescope in the 1.5–1.8GHz range.By employing spectral energy distribution(SED)and spectral sharpness methods,we confirmed the presence of narrow-band radiation in FRB 20190520B,which is crucial for understanding its radiation mechanisms.Our findings support the narrow-band characteristics that most repeaters exhibit.This work also highlights the necessity of continued multiband observations to explore its periodicity and frequency-dependent properties,contributing to an in-depth understanding of FRB phenomena. 展开更多
关键词 FAST narrow BAND
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Single crystal growth and transport properties of narrow-bandgap semiconductor RhP_(2)
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作者 吴德胜 郑萍 雒建林 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期545-549,共5页
We report the growth of high-quality single crystals of RhP_(2),and systematically study its structure and physical properties by transport,magnetism,and heat capacity measurements.Single-crystal x-ray diffraction rev... We report the growth of high-quality single crystals of RhP_(2),and systematically study its structure and physical properties by transport,magnetism,and heat capacity measurements.Single-crystal x-ray diffraction reveals that RhP_(2) adopts a monoclinic structure with the cell parameters a=5.7347(10)A,b=5.7804(11)A,and c=5.8222(11)A,space group P2_(1)/c(No.14).The electrical resistivityρ(T)measurements indicate that RhP_(2) exhibits narrow-bandgap behavior with the activation energies of 223.1 meV and 27.4 meV for two distinct regions,respectively.The temperaturedependent Hall effect measurements show electron domain transport behavior with a low charge carrier concentration.We find that RhP_(2) has a high mobilityμ_(e)~210 cm^(2)·V^(-1)·s^(-1)with carrier concentrations n_(e)~3.3×10^(18)cm^(3) at 300 K with a narrow-bandgap feature.The high mobilityμ_(e) reaches the maximum of approximately 340 cm^(2)·V^(-1)·s^(-1)with carrier concentrations n_^(e)~2×10^(18)cm^(-3)at 100 K.No magnetic phase transitions are observed from the susceptibilityχ(T)and specific heat C_(p)(T)measurements of RhP_(2).Our results not only provide effective potential as a material platform for studying exotic physical properties and electron band structures but also motivate further exploration of their potential photovoltaic and optoelectronic applications. 展开更多
关键词 single crystal growth narrow band system electrical transport high mobilities
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A Comprehensive Study on the digestive Endoscopic Technique and Narrow-Band Imaging for Early Gastric Cancer Screening
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作者 Jing Ma 《Proceedings of Anticancer Research》 2024年第1期99-104,共6页
Objective:To explore the implementation of gastrointestinal endoscopy technology and endoscopic narrow-band imaging(NBI)in the early screening of gastric cancer and to observe and study their application effects.Metho... Objective:To explore the implementation of gastrointestinal endoscopy technology and endoscopic narrow-band imaging(NBI)in the early screening of gastric cancer and to observe and study their application effects.Methods:During the period from March 2023 to August 2023,312 patients who received gastroscopy in the Kunming Guandu District People’s Hospital were selected,and they underwent both conventional gastroscopy and endoscopic NBI,with clinicopathological tissue biopsy serving as the gold standard.The application value for early screening of gastric cancer was observed and analyzed.Results:The scoring data showed that the clarity of gastric mucosal glandular tube structure,microvascular structure clarity,and lesion contour scoring data of conventional gastroscopy were lower than those of the NBI technology(P<0.05).The screening rate of pathological biopsy in 312 patients was 18.59%(58 cases).Conventional gastroscopy showed a screening rate of 11.53%(36 cases),while NBI technology examined a screening rate of 17.63%(55 cases),and the two-by-two comparison of the screening rate data of the three groups was not statistically significant(P>0.05).The sensitivity,specificity,accuracy,positive predictive value,and negative predictive value of conventional gastroscopy appeared to be lower than those of NBI technology(P<0.05).Conclusion:In the early screening of gastric cancer,endoscopic NBI technology can be applied to patients.Compared with conventional gastroscopy,it provides a clearer visualization of the structure of the gastric mucosal glandular structure and microvascular structure,with a certain screening rate.Additionally,its sensitivity,specificity,accuracy,positive predictive value,and negative predictive value are higher,demonstrating outstanding effectiveness. 展开更多
关键词 Gastric cancer Early screening Gastrointestinal endoscopy technology Endoscopic narrow band imaging technology Application effect
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8-nm narrowband photodetection in diamonds 被引量:1
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作者 Lemin Jia Lu Cheng Wei Zheng 《Opto-Electronic Science》 2023年第7期1-11,共11页
Spectrally-selective photodetection plays a crucial role in various applications,including target imaging and environmental monitoring.Traditional deep-ultraviolet(DUV)narrowband photodetection systems consist of broa... Spectrally-selective photodetection plays a crucial role in various applications,including target imaging and environmental monitoring.Traditional deep-ultraviolet(DUV)narrowband photodetection systems consist of broadband photodetectors and filters,which complicates the architecture and constrains imaging quality.Here,we introduce an electronic-grade diamond single-crystal photodetector exhibiting an exceptionally narrow spectral response in the DUV range with a full width at half maximum of 8 nm.By examining diamond photodetectors with varying dislocation densities,we propose that mitigating the defect-induced trapping effect to achieve charge collection narrowing,assisted by free exciton radiative recombination,is an effective strategy for narrowband photodetection.The superior performance of this device is evidenced through the imaging of DUV light sources,showcasing its capability to differentiate between distinct light sources and monitor human-safe sterilization systems.Our findings underscore the promising potential applications of electronicgrade diamond in narrowband photodetection and offer a valuable technique for identifying electronic-grade diamond. 展开更多
关键词 narrowband photodetection electronic-grade diamond charge collection narrowing
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Generating a tunable narrow electron beam comb via laser-driven plasma grating 被引量:1
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作者 Hetian Yang Jingwei Wang +3 位作者 Shixia Luan Ke Feng Wentao Wang Ruxin Li 《Matter and Radiation at Extremes》 SCIE EI CSCD 2023年第6期4-10,共7页
We propose a novel approach for generating a high-density,spatially periodic narrow electron beam comb(EBC)from a plasma grating induced by the interference of two intense laser pulses in subcritical-density plasma.We... We propose a novel approach for generating a high-density,spatially periodic narrow electron beam comb(EBC)from a plasma grating induced by the interference of two intense laser pulses in subcritical-density plasma.We employ particle-in-cell(PIC)simulations to investigate the effects of cross-propagating laser pulses with specific angles overlapping in a subcritical plasma.This overlap results in the formation of a transverse standing wave,leading to a spatially periodic high-density modulation known as a plasma grating.The electron density peak within the grating can reach several times the background plasma density.The charge imbalance between electrons and ions in the electron density peaks causes mutual repulsion among the electrons,resulting in Coulomb expansion and acceleration of the electrons.As a result,some electrons expand into vacuum,forming a periodic narrow EBC with an individual beam width in the nanoscale range.To further explore the formation of the nanoscale EBC,we conduct additional PIC simulations to study the dependence on various laser parameters.Overall,our proposed method offers a promising and controlled approach to generate tunable narrow EBCs with high density. 展开更多
关键词 TUNABLE narrow beam
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A comparative study of the electrical characteristics of positive and negative narrow bipolar events
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作者 FeiFan Liu BaoYou Zhu +3 位作者 HeLin Zhou GaoPeng Lu Ming Ma JiuHou Lei 《Earth and Planetary Physics》 CAS CSCD 2023年第6期675-683,共9页
Narrow bipolar events(NBEs)are intriguing intra-cloud discharge that have attracted enormous interest in the lightning community.They come with two polarities that dominate at different altitudes in thunderclouds.The ... Narrow bipolar events(NBEs)are intriguing intra-cloud discharge that have attracted enormous interest in the lightning community.They come with two polarities that dominate at different altitudes in thunderclouds.The sources of negative NBEs are usually located near the top of thunderclouds;those of positive NBEs are at the middle levels.NBEs may occur at the onset of lightning.The electrical properties of NBEs remain poorly understood.We present here the first comparative study of the electrical characteristics of negative and positive NBEs.To derive electrical parameters from the fast electric field change waveforms of 1673 positive NBEs and 364 negative NBEs recorded by the Jianghuai Area Sferic Array(JASA)in China,we use an improved method based on the transmission line model.This approach concludes that negative NBEs occurring at high altitudes tend to produce a narrower current pulse and take a shorter time to traverse the channel than their positive counterparts.Moreover,compared to positive NBEs,a larger portion of negative NBEs are associated with slightly greater peak current moments but smaller overall charge moments.The differences reported herein between electrical properties of negative and positive NBEs suggest that charge distribution in NBE-producing thunderstorms tends to vary systematically with altitude. 展开更多
关键词 LIGHTNING THUNDERSTORM narrow bipolar events
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Anterior Chamber Depth Changes in Narrow Iridocorneal Angles after Phacoemulsification
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作者 Md. Ariful Islam Abir Bin Sajj +2 位作者 Tohura Sharmin Md. Sanwar Hossain Md. Shafiqul Islam 《Open Journal of Ophthalmology》 2023年第2期187-198,共12页
Background: The burden of cataract and glaucoma has been increasing. Primary angle closure occurs as a result of crowded anterior segment anatomy causing appositional contact between peripheral iris and trabecular mes... Background: The burden of cataract and glaucoma has been increasing. Primary angle closure occurs as a result of crowded anterior segment anatomy causing appositional contact between peripheral iris and trabecular meshwork. Lens extraction has been proposed as a method of deepening anterior chamber and managing intraocular pressure. Purpose: To assess changes in anterior chamber depth after phacoemulsification with intraocular lens implantation in narrow angle eyes. Design: Prospective controlled trial (before-after) study. Method: The study was conducted from March 2015 to August 2017 among the patients of department of Ophthalmology of BSMMU who were diagnosed as cataract with narrow angles. Anterior chamber angle grading of 2 or less (Shaffer grading) in 3 or more quadrants was considered narrow angle (NA). The purposive type sampling technique was applied to collect sample from the study population, as per inclusion and exclusion criteria. Complete clinical evaluation including history, physical examination, relevant ocular examinations and systemic examinations were performed. In this prospective study, subjects underwent phacoemulsification with foldable lens implantation. A scan ultrasonography was performed preoperatively and 10<sup>th</sup> and 30<sup>th</sup> postoperative days of surgery. Results: Thirty eyes of 29 patients included in the study, male: female ratio was 1:1, with an overall mean age of 62.03 ± 8.95 years. The mean preoperative central ACD was 2.95 ± 0.35 mm. At 10<sup>th</sup> and 30<sup>th</sup> POD mean central ACD were 3.94 ± 0.32, and 3.92 ± 0.28 mm respectively. Mean of increase in central ACD at final follow-up was 0.96 mm (p Conclusion: Phacoemulsification with posterior chamber in bag lens implantation can deepen the anterior chamber depth in patients with narrow angles. Based on these findings, it is concluded that phacoemulsification with foldable intraocular lens implantation is an effective tool in deepening the anterior chamber. 展开更多
关键词 Anterior Chamber Depth PHACOEMULSIFICATION Iridocorneal Angles Open Angle narrow Angle
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A seismic modeling analysis of wide and narrow 3D observation systems for channel sand bodies 被引量:4
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作者 狄帮让 徐秀仓 魏建新 《Applied Geophysics》 SCIE CSCD 2008年第4期294-300,共7页
The effect of the wide and narrow azimuth 3D observation systems on seismic imaging precision is becoming a hot area for studies of high precision 3D seismic acquisition methods in recent years. In this paper we utili... The effect of the wide and narrow azimuth 3D observation systems on seismic imaging precision is becoming a hot area for studies of high precision 3D seismic acquisition methods in recent years. In this paper we utilize 3D physical seismic modeling experiments. A 3D channel sand body physical seismic model is constructed and two acquisition systems are designed with wide azimuth (16 lines) and narrow azimuth (8 lines) to model 3D seismic data acquisition and processing seismic work flows. From analysis of migrated time slice data with high quality and small size, we conclude that when the overlying layers are smooth and lateral velocities have little change, both wide and narrow azimuth observation systems in 3D acquisition can be used for obtaining high precision imaging and equivalent resolution of the channel sand body. 展开更多
关键词 Wide and narrow azimuth observation systems seismic imaging physicalseismic modeling time slice RESOLUTION
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Effective use of the Japan Narrow Band Imaging Expert Team classification based on diagnostic performance and confidence level 被引量:6
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作者 Daizen Hirata Hiroshi Kashida +4 位作者 Mineo Iwatate Tomomasa Tochio Akira Teramoto Yasushi Sano Masatoshi Kudo 《World Journal of Clinical Cases》 SCIE 2019年第18期2658-2665,共8页
Five years have passed since the Japan Narrow Band Imaging Expert Team (JNET) classification was proposed in 2014. However, the diagnostic performance of this classification has not yet been established. We conducted ... Five years have passed since the Japan Narrow Band Imaging Expert Team (JNET) classification was proposed in 2014. However, the diagnostic performance of this classification has not yet been established. We conducted a retrospective study and a systematic search of Medical Literature Analysis and Retrieval System On-Line. There were three retrospective single center studies about the diagnostic performance of this classification. In order to clarify this issue, we reviewed our study and three previous studies. This review revealed the diagnostic performance in regards to three important differentiations.(1) Neoplasia from non-neoplasia;(2) malignant neoplasia from benign neoplasia;and (3) deep submucosal invasive cancer (D-SMC) from other neoplasia. The sensitivity in differentiating neoplasia from non-neoplasia was 98.1%-99.8%. The specificity in differentiating malignant neoplasia from benign neoplasia was 84.7%-98.2% and the specificity in the differentiation D-SMC from other neoplasia was 99.8%-100.0%. This classification would enable endoscopists to identify almost all neoplasia, to appropriately determine whether to perform en bloc resection or not, and to avoid unnecessary surgery. This article is the first review about the diagnostic performance of the JNET classification. Previous reports about the diagnostic performance have all been retrospective single center studies. A large-scale prospective multicenter evaluation study is awaited for the validation. 展开更多
关键词 JAPAN narrow Band IMAGING EXPERT TEAM CLASSIFICATION Magnifying endoscopy narrow-BAND IMAGING Validation Diagnostic performance Colonoscopy Colorectal neoplasms
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Numerical simulation of bubble breakup phenomena in anarrow flow field 被引量:1
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作者 张阿漫 倪宝玉 +1 位作者 宋炳月 姚熊亮 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2010年第4期449-460,共12页
Based on the boundary integral method, a 3D bubble breakup model in a narrow flow field is established, and a corresponding computation program is developed to simulate the symmetrical and asymmetrical bubble breakup.... Based on the boundary integral method, a 3D bubble breakup model in a narrow flow field is established, and a corresponding computation program is developed to simulate the symmetrical and asymmetrical bubble breakup. The calculated results are compared with the experimental results and agree with them very well, indicating that the numerical model is valid. Based on the basic behavior of bubbles in a narrow flow field, the symmetrical and asymmetrical bubble breakup is studied systematically using the developed program. A feasibility rule of 3D bubble breakup is presented. The dynamics of sub-bubbles after splitting is studied. The influences of characteristic parameters on bubble breakup and sub-bubble dynamics are analyzed. 展开更多
关键词 BUBBLE BREAKUP narrow flow field sub-bubble narrow jet
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Bounds of Interpolation Error for Arbitrary Narrow Quadrilateral Quasi-Wilson Element
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作者 李清善 陈绍春 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第3期22-28,共7页
Based on the construction of reference e le ment and bilinear transformation, a quasi-Wilson element for arbitrary narrow q uadrilateral is presented. Using the interpolation Theorem for narrow quadrilate ral isoparam... Based on the construction of reference e le ment and bilinear transformation, a quasi-Wilson element for arbitrary narrow q uadrilateral is presented. Using the interpolation Theorem for narrow quadrilate ral isoparametric finite element and related methods, the bounds of interpolatio n error for arbitrary narrow quadrilateral quasi-Wilson element are obtained in case when the condition ρ K/h K≥σ 0】0 is not satisfied, where h K is the diameter of the element K and ρ K is the diameter of an ins cribed circle in K. The interpolation error is O(h2 K) in the L2( K)-norm and O(h K) in the H1(K) -norm provided that the in terpolated function belongs to H2(K). 展开更多
关键词 interpolation error quasi-Wilson element arbi trary narrow quadrilateral non-regularity
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Distribution of Panama’s narrow-range trees:are there hot-spots?
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作者 Elizabeth Tokarz Richard Condit 《Forest Ecosystems》 SCIE CSCD 2021年第4期801-809,共9页
Background:Tree species with narrow ranges are a conservation concern because heightened extinction risk accompanies their small populations.Assessing risks for these species is challenging,however,especially in tropi... Background:Tree species with narrow ranges are a conservation concern because heightened extinction risk accompanies their small populations.Assessing risks for these species is challenging,however,especially in tropical flora where their sparse populations seldom appear in traditional plots and inventories.Here,we utilize instead large scale databases that combine tree records from many sources to test whether the narrow-range tree species of Panama are concentrated at certain elevations or in certain provinces.Past investigations have suggested that the Choco region of eastern Panama and the high mountains of western Panama may be potential hotspots of narrow-range tree species.Methods:All individual records were collected from public databases,and the range size of each tree species found in Panama was estimated as a polygon enclosing all its locations.Species with ranges<20,000 km^(2) were defined as narrow endemics.We divided Panama into geographic regions and elevation zones and counted the number of individual records and the species richness in each,separating narrow-range species from all other species.Results:The proportion of narrow endemics peaked at elevations above 2000 m,reaching 17.2% of the species recorded.At elevation<1500 m across the country,the proportion was 6-11%,except in the dry Pacific region,where it was 1.5%.Wet forests of the Caribbean coast had 8.4% narrow-range species,slightly higher than other regions.The total number of narrow endemics,however,peaked at mid-elevation,not high elevation,because total species richness was highest at mid-elevation.Conclusions:High elevation forests of west Panama had higher proportions of narrow endemic trees than low-elevation regions,supporting their hot-spot status,while dry lowland forests had the lowest proportion.This supports the notion that montane forests of Central America should be a conservation focus.However,given generally higher diversity at low-to mid-elevation,lowlands are also important habitats for narrow-range tree species,though conservation efforts here may not protect narrow-range tree species as efficiently. 展开更多
关键词 narrow endemic trees Biodiversity hot-spots PANAMA RAREFACTION High elevations BIEN database narrow-range
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Inundation Calculation of the Coastal Narrow Plain Strip Impacted by Upstream Reservoir Flood Discharge in Rainy and Extreme Flood Conditions
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作者 Nguyen Ngoe Naml Le Van Nghi Bui Thi Ngan 《Journal of Shipping and Ocean Engineering》 2016年第3期165-178,共14页
In the context of current climate change, an abnormality of flooding is a common form of disaster in Vietnam. Hanh Stream reservoir has occurred great flood in 1986, 2010. In the future, the risk of flooding is possib... In the context of current climate change, an abnormality of flooding is a common form of disaster in Vietnam. Hanh Stream reservoir has occurred great flood in 1986, 2010. In the future, the risk of flooding is possible to happen again. In view of management of the risk of natural disasters: large flooding situation downstream is one of the most dangerous risks for the reservoir. Due to downstream of Hanh Stream reservoir is a narrow coastal plains, quick infrastructure development, especially interwoven road and railway systems, so that flood drainage ability will be affected greatly. The consciousness of risks that may be occurred in the future in order to propose preventive measures and proactive response to minimize damages always is the requirement for all projects. The hydrodynamic calculation, flooding maps, emergency plan to prevent flooding downstream of Hanh Stream reservoir is also needed. The article is raised the issue of requirements to calculate coastal narrow delta strip flooding in the Central of Vietnam when impacted by the upstream reservoir of flood discharge in terms of extreme heavy rain and flooding and presented computational methods of Mike software package for case flooded plain of Cam Ranh Bay in downstream reservoirs of Hanh Stream, Khanh Hoa Province, Vietnam. 展开更多
关键词 Reservoirs Hanh Stream maps INUNDATION narrow plain narrow delta coastal hydrodynamic calculation flood flooding.
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Diagnosis of early gastric cancer using narrow band imaging and acetic acid 被引量:9
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作者 Ken Matsuo Hidetoshi Takedatsu +7 位作者 Michita Mukasa Hiroaki Sumie Hikaru Yoshida Yasutomo Watanabe Jun Akiba Keita Nakahara Osamu Tsuruta Takuji Torimura 《World Journal of Gastroenterology》 SCIE CAS 2015年第4期1268-1274,共7页
AIM: To determine whether the endoscopic findings of depressed-type early gastric cancers(EGCs) could precisely predict the histological type.METHODS: Ninety depressed-type EGCs in 72 patients were macroscopically and... AIM: To determine whether the endoscopic findings of depressed-type early gastric cancers(EGCs) could precisely predict the histological type.METHODS: Ninety depressed-type EGCs in 72 patients were macroscopically and histologically identified. We evaluated the microvascular(MV) and mucosal surface(MS) patterns of depressed-type EGCs using magnifying endoscopy(ME) with narrow-band imaging(NBI)(NBI-ME) and ME enhanced by 1.5% acetic acid, respectively. First, depressed-type EGCs were classified according to MV pattern by NBI-ME. Subsequently, EGCs unclassified by MV pattern were classified according to MS pattern by enhanced ME(EME) images obtained from the same angle.RESULTS: We classified the depressed-type EGCs into the following 2 MV patterns using NBI-ME: a fine-network pattern that indicated differentiated adenocarcinoma(25/25, 100%) and a corkscrew pattern that likely indicated undifferentiated adenocarcinoma(18/23, 78.3%). However, 42 of the 90(46.7%) lesions could not be classified into MV patterns by NBI-ME. These unclassified lesions were then evaluated for MS patterns using EME, which classified 33(81.0%) lesions as MS patterns, diagnosed as differentiated adenocarcinoma. As a result, 76 of the 90(84.4%) lesions were matched with histological diagnoses using a combination of NBI-ME and EME.CONCLUSION: A combination of NBI-ME and EME was useful in predicting the histological type of depressedtype EGC. 展开更多
关键词 narrow BAND imaging Magnifying ENDOSCOPY Acetic AC
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Narrow band imaging with magnification for the diagnosis of lesions in the upper gastrointestinal tract 被引量:13
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作者 Rajvinder Singh Asif Hussain Cheong Kuan Loong 《World Journal of Gastrointestinal Endoscopy》 CAS 2013年第12期584-589,共6页
Endoscopy plays an important role in the diagnosis and management of gastrointestinal(GI)tract disorders.Chromoendoscopy has proven to be superior to white light endoscopy for early detection of various GI lesions.Thi... Endoscopy plays an important role in the diagnosis and management of gastrointestinal(GI)tract disorders.Chromoendoscopy has proven to be superior to white light endoscopy for early detection of various GI lesions.This has however been fraught with problems.The use of color stains,time taken to achieve an effect and the learning curve associated with the technique has been some of the pitfalls.Narrow band imaging(NBI)particularly in combination with magnifying endoscopy may allow the endoscopist to accomplish a fairly accurate diagnosis with good histological correlation similar to results achieved with chromoendoscopy.Such enhanced detection of pre-malignant and early neoplastic lesions in the gastrointestinal tract should allow better targeting of biopsies and could ultimately prove to be cost effective.Various studies have been done demonstrating the utility of this novel technology.This article will review the impact of NBI in the diagnosis of upper gastrointestinal tract disorders. 展开更多
关键词 narrow band imaging Magnifying ENDOSCOPY Upper GASTROINTESTINAL TRACT
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Narrow-band imaging with magnifying endoscopy for the evaluation of gastrointestinal lesions 被引量:12
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作者 Alina Boeriu Cristian Boeriu +4 位作者 Silvia Drasovean Ofelia Pascarenco Simona Mocan Mircea Stoian Daniela Dobru 《World Journal of Gastrointestinal Endoscopy》 CAS 2015年第2期110-120,共11页
Narrow band imaging(NBI) endoscopy is an optical image enhancing technology that allows a detailed inspection of vascular and mucosal patterns, providing the ability to predict histology during real-time endoscopy. By... Narrow band imaging(NBI) endoscopy is an optical image enhancing technology that allows a detailed inspection of vascular and mucosal patterns, providing the ability to predict histology during real-time endoscopy. By combining NBI with magnification endoscopy(NBI-ME), the accurate assessment of lesions in the gastrointestinal tract can be achieved, as well as the early detection of neoplasia by emphasizing neovascularization. Promising results of the method in the diagnosis of premalignant and malignant lesions of gastrointestinal tract have been reported in clinical studies. The usefulness of NBI-ME as an adjunct to endoscopic therapy in clinical practice, the potential to improve diagnostic accuracy, surveillance strategies and cost-saving strategies based on this method are summarized in this review. Various classification systems of mucosal and vascular patterns used to differentiate preneoplastic and neoplastic lesions have been reviewed. We concluded that the clinical applicability of NBI-ME has increased, but standardization of endoscopic criteria and classification systems, validation in randomized multicenter trials and training programs to improve the diagnostic performance are all needed before the widespread acceptance of the method in routine practice. However, published data regarding the usefulness of NBI endoscopy are relevant in order to recommend the method as a reliable tool in diagnostic and therapy, even for less experienced endoscopists. 展开更多
关键词 narrow band imaging magnifying ENDOSCOPY PREMALIGNANT Early cancer MUCOSAL patterns Vascularpatterns
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Surrounding rock control of gob-side entry driving with narrow coal pillar and roadway side sealing technology in Yangliu Coal Mine 被引量:7
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作者 Zha Wenhua Shi Hao +1 位作者 Liu San Kang Changhao 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第5期819-823,共5页
Gob-side entry driving can increase coal recovery ratio, and it is implied in many coal mines. Based on geological condition of 10416 working face tailentry in Yangliu Coal Mine, the surrounding rock deformation chara... Gob-side entry driving can increase coal recovery ratio, and it is implied in many coal mines. Based on geological condition of 10416 working face tailentry in Yangliu Coal Mine, the surrounding rock deformation characteristics of gob-side entry driving with narrow coal pillar is analysed, reasonable size of coal pillar and reasonable roadway excavation time after mining are achieved. Surrounding rock control technology and effective roadway side sealing technology are proposed and are taken into field practice. The results showed that a safer and more efficient mining of working face can be achieved. In addition, results of this paper also have important theoretical significance and valuable reference for surrounding rock control technology of gob-side entry driving with narrow coal pillar under special geological condition. 展开更多
关键词 narrow coal PILLAR Gob-side ENTRY driving SURROUNDING rock control ROADWAY SIDE sealing technology
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A case of gastric mucosa-associated lymphoid tissue lymphoma in which magnified endoscopy with narrow band imaging was useful in the diagnosis 被引量:10
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作者 Kouichi Nonaka Keiko Ishikawa +9 位作者 Shin Arai Masamitsu Nakao Michio Shimizu Takaki Sakurai Koji Nagata Makoto Nishimura Osamu Togawa Yasutoshi Ochiai Yutaka Sasaki Hiroto Kita 《World Journal of Gastrointestinal Endoscopy》 CAS 2012年第4期151-156,共6页
Recently, we reported a case of gastric mucosaassociated lymphoid tissue (MALT) lymphoma presenting with unique vascular features. In the report, we defined the tree-like appearance (TLA) on the images of abnormal blo... Recently, we reported a case of gastric mucosaassociated lymphoid tissue (MALT) lymphoma presenting with unique vascular features. In the report, we defined the tree-like appearance (TLA) on the images of abnormal blood vessels which resembled branches from the trunk of a tree in the shiny mucosa, in which the glandular structure was lost. The 67-year-old female was diagnosed with gastric MALT lymphoma. The patient received eradication therapy for H. pylori. Conventional endoscopy revealed multiple ill-delineated brownish depressions in the stomach and cobblestonelike mucosa was observed at the greater curvature to the posterior wall of the upper gastric body 7 mo after successful eradication. Unsuccessful treatment of gastric MALT lymphoma was suspected on conventional endoscopy. Conventional endoscopic observations found focal depressions and cobblestone-like appearance, and these lesions were subsequently observed using magnified endoscopy combined with narrow band imaging to identify abnormal vessels presenting with a TLA within the lesions. Ten biopsies were taken from the area where abnormal vessels were present within these lesions. Ten biopsies were also taken from the lesions without abnormal vessels as a control. A total of 20 biopsy samples were evaluated to determine whether the diagnosis of MALT lymphoma could be obtained histologically from each sample. A positive diagnosis was obtained in 8/10 TLA (+) sites and in 2/10 TLA(-) sites. Target biopsies of the site with abnormal blood vessels can potentially improve diagnostic accuracy of gastric MALT lymphoma. 展开更多
关键词 MUCOSA associated-lymphoid tissue Magnified ENDOSCOPY narrow band imaging Tree-like APPEARANCE
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Experimental and numerical study on the growth and collapse of a bubble in a narrow tube 被引量:7
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作者 Bao-Yu Ni A-Man Zhang +1 位作者 Qian-Xi Wang Bin Wang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第5期1248-1260,共13页
The growth, expansion and collapse of a bubble in a narrow tube are studied using both experiments and numerical simulations. In experiment, the bubble is generated by an electric spark in a water tank and recorded by... The growth, expansion and collapse of a bubble in a narrow tube are studied using both experiments and numerical simulations. In experiment, the bubble is generated by an electric spark in a water tank and recorded by a highspeed camera system. In numerical simulation, the evolution of the bubble is solved by adopting axisymmetric boundary integral equation, considering the surface tension effect. The results of experiments and numerical simulations are compared and good agreements are achieved. Both of them show that a counter-jet forms and penetrates the bubble at the end of the collapse stage, before a ring type bubble forms. Under the attraction of the tube wall due to Bjerknes force, a ring jet is generated, pointing towards the tube. On the basis of this, some physical quantities like the pressure on the tube wall and kinetic energy are calculated in a case study. The effects of tube diameters and tube lengths on the bubble's behaviors are also investigated. 展开更多
关键词 narrow tube Ring bubble Counter-jet Ringjet Bubble experiment
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Tolerability of magnifying narrow band imaging endoscopy for esophageal cancer screening 被引量:5
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作者 Yasushi Yamasaki Ryuta Takenaka +6 位作者 Keisuke Hori Koji Takemoto Seiji Kawano Yoshiro Kawahara Hiroyuki Okada Shigeatsu Fujiki Kazuhide Yamamoto 《World Journal of Gastroenterology》 SCIE CAS 2015年第9期2793-2799,共7页
AIM:To compare the tolerability of magnifying narrow band imaging endoscopy for esophageal cancer screening with that of lugol chromoendoscopy.METHODS:We prospectively enrolled and analyzed 51 patients who were at hig... AIM:To compare the tolerability of magnifying narrow band imaging endoscopy for esophageal cancer screening with that of lugol chromoendoscopy.METHODS:We prospectively enrolled and analyzed 51 patients who were at high risk for esophageal cancer.All patients were divided into two groups:a magnifying narrow band imaging group,and a lugol chromoendoscopy group,for comparison of adverse symptoms.Esophageal cancer screening was performed on withdrawal of the endoscope.The primary endpoint was a score on a visual analogue scale for heartburn after the examination.The secondary endpoints were scale scores for retrosternal pain and dyspnea after the examinations,change in vital signs,total procedure time,and esophageal observation time.RESULTS:The scores for heartburn and retrosternal pain in the magnifying narrow band imaging group were significantly better than those in the lugol chromoendoscopy group(P =0.004,0.024,respectively,ANOVA for repeated measures).The increase in heart rate after the procedure was significantly greater in the lugol chromoendoscopy group.There was no significant difference between the two groups with respect to othervital sign.The total procedure time and esophageal observation time in the magnifying narrow band imaging group were significantly shorter than those in the lugol chromoendoscopy group(450 ± 116 vs 565 ± 174,P =0.004,44 ± 26 vs 151 ± 72,P < 0.001,respectively).CONCLUSION:Magnifying narrow band imaging endoscopy reduced the adverse symptoms compared with lugol chromoendoscopy.Narrow band imaging endoscopy is useful and suitable for esophageal cancer screening periodically. 展开更多
关键词 narrow band imaging Lugol ADVERSE SYMPTOMS Visual
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