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Intraseasonal variability of the Kuroshio observed via mooring at 18°N
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作者 Xin YUAN Qingye WANG +2 位作者 Jie MA Shijian HU Dunxin HU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第2期468-483,共16页
Insufficient observations near the origin of the Kuroshio have led to incomplete understanding of the intraseasonal variability(ISV)of the Kuroshio.Direct measurements of the Kuroshio velocity were performed with an a... Insufficient observations near the origin of the Kuroshio have led to incomplete understanding of the intraseasonal variability(ISV)of the Kuroshio.Direct measurements of the Kuroshio velocity were performed with an array of three profiler moorings(122.7°E,123°E,and 123.3°E)along 18°N from January 2018 to February 2020.The ISV of the Kuroshio at 18°N was investigated based on a combination of mooring observations and global high-resolution HYbrid Coordinate Ocean Model reanalysis data.The estimated time-averaged transport in the upper 350 m across the observation transect was 6.5±2.6 Sv(1.0 Sv=10^(6)m^(3)/s).Two significant ISV peaks at 50-60 and~100 d were recognized in the power spectra of the meridional velocity and transport.Further analysis indicated that the ISV at 50-60 d was caused by westward-propagating eddies at average propagation speed of~13 cm/s and wavelength of~635 km.Another ISV peak at~100 d was mainly caused by northward-propagating eddies generated in the North Equatorial Current region.Further investigation indicated that the ISV of the Kuroshio at 18°N is dominated by meridional transport,rather than by the zonal migration of the Kuroshio main axis.Our findings provide a better understanding of the ISV of the Kuroshio east of Luzon Island. 展开更多
关键词 intraseasonal variability(ISV) KUROSHIO mooring observation EDDY
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The First Global Map of Atmospheric Ammonia(NH_(3)) as Observed by the HIRAS/FY-3D Satellite
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作者 Minqiang ZHOU Zhili DENG +6 位作者 Charles ROBERT Xingying ZHANG Lu ZHANG Yapeng WANG Chengli QI Pucai WANG Martine De MAZIÈRE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第3期379-390,共12页
Atmospheric ammonia(NH_(3)) is a chemically active trace gas that plays an important role in the atmospheric environment and climate change. Satellite remote sensing is a powerful technique to monitor NH_(3) concentra... Atmospheric ammonia(NH_(3)) is a chemically active trace gas that plays an important role in the atmospheric environment and climate change. Satellite remote sensing is a powerful technique to monitor NH_(3) concentration based on the absorption lines of NH_(3) in the thermal infrared region. In this study, we establish a retrieval algorithm to derive the NH_(3)column from the Hyperspectral Infrared Atmospheric Sounder(HIRAS) onboard the Chinese Feng Yun(FY)-3D satellite and present the first atmospheric NH_(3) column global map observed by the HIRAS instrument. The HIRAS observations can well capture NH_(3) hotspots around the world, e.g., India, West Africa, and East China, where large NH_(3) emissions exist. The HIRAS NH_(3) columns are also compared to the space-based Infrared Atmospheric Sounding Interferometer(IASI)measurements, and we find that the two instruments observe a consistent NH_(3) global distribution, with correlation coefficient(R) values of 0.28–0.73. Finally, some remaining issues about the HIRAS NH_(3) retrieval are discussed. 展开更多
关键词 AMMONIA HIRAS/FY-3D satellite thermal-infrared observation remote sensing optimal estimation method
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Data-Driven Modeling of Partially Observed Biological Systems
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作者 Wei-Hung Su Ching-Shan Chou Dongbin Xiu 《Communications on Applied Mathematics and Computation》 EI 2024年第1期739-754,共16页
We present a numerical approach for modeling unknown dynamical systems using partially observed data,with a focus on biological systems with(relatively)complex dynamical behavior.As an extension of the recently develo... We present a numerical approach for modeling unknown dynamical systems using partially observed data,with a focus on biological systems with(relatively)complex dynamical behavior.As an extension of the recently developed deep neural network(DNN)learning methods,our approach is particularly suitable for practical situations when(i)measurement data are available for only a subset of the state variables,and(ii)the system parameters cannot be observed or measured at all.We demonstrate that,with a properly designed DNN structure with memory terms,effective DNN models can be learned from such partially observed data containing hidden parameters.The learned DNN model serves as an accurate predictive tool for system analysis.Through a few representative biological problems,we demonstrate that such DNN models can capture qualitative dynamical behavior changes in the system,such as bifurcations,even when the parameters controlling such behavior changes are completely unknown throughout not only the model learning process but also the system prediction process.The learned DNN model effectively creates a“closed”model involving only the observables when such a closed-form model does not exist mathematically. 展开更多
关键词 Deep neural network(DNN) Governing equation discovery Biological system Partial observation
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An Analysis of Observed Ocean Currents Data and Numerical Simulation in the Offshore Area of Jiaonan 被引量:3
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作者 刘伟峰 孙英兰 张学庆 《Marine Science Bulletin》 CAS 2006年第2期1-11,共11页
Based on the diurnal consecutively observed data in the offshore area of Jiaonan in 2005, the paper tries to make a preliminary analysis of the specificity of ocean currents, tidal current property and residual curren... Based on the diurnal consecutively observed data in the offshore area of Jiaonan in 2005, the paper tries to make a preliminary analysis of the specificity of ocean currents, tidal current property and residual current property in the area in observing dates. Then on the basis of observed data analysis and by employing the split-step method, the paper conducts a numerical simulation of the tidal current field, which can show the M2 tidal constituent tidal wave system, current ellipse distribution, maximum current velocity distribution and time-dependent current field. The calculated results agree well with the observed data, which can on the one hand reflect the basic specificities of temporal and spatial distribution of the M2 tidal constituent current field to some extent, and, on the other hand, offer more information about the hydrodynamic condition. So the paper would provide a scientific basis for the making of sea environment protection plans in the offshore area of Jiaonan under certain conditions. 展开更多
关键词 ocean currents observed data numerical calculation Jiaonan
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The observed currents in summer in the Bohai Sea 被引量:5
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作者 乔璐璐 鲍献文 吴德星 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第2期130-136,共7页
A harmonic method was used to analyze the tidal currents observed in summer at 11 stations made from 1996 to 2001 in the Bohai Sea, China. Data was compared among different instruments and intervals. Elliptic elements... A harmonic method was used to analyze the tidal currents observed in summer at 11 stations made from 1996 to 2001 in the Bohai Sea, China. Data was compared among different instruments and intervals. Elliptic elements were calculated based on harmonic constants, of which vertical distributions of the maximum speed and rotation direction were discussed for understanding the characteristics of diurnal and semi-diurnal tidal current components. The results indicate that the maximum speed of M2 tidal current component is much larger than that of K1; the rotation direction of M2 tidal current constituent is clockwise in the central part of the Bohai Sea and in the Laizhou Bay, but anticlockwise in the Liaodong Bay and Bohai Bay. For K1 tidal current constituent, it is clockwise in the central Bohai Sea but anti-clockwise in the Laizhou Bay and Liaodong Bay. The tidal currents in most stations in the Bohai Sea were regular semidiurnal except for those in the central Bohai Sea, being irregular semidiurnal. 展开更多
关键词 observed tidal current the Bohai Sea harmonic analysis
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A new type of internal solitary waves with a re-appearance period of 23 h observed in the South China Sea 被引量:8
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作者 CHEN Liang ZHENG Quanan +2 位作者 XIONG Xuejun YUAN Yeli XIE Huarong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第9期116-118,共3页
The South China Sea (SCS), in particular the northern SCS, is one of ocean areas where energetic internal solitary waves (ISWs)occur most frequently (Cai et al., 2012; Zheng, 2017). Based on the re-appearance pe... The South China Sea (SCS), in particular the northern SCS, is one of ocean areas where energetic internal solitary waves (ISWs)occur most frequently (Cai et al., 2012; Zheng, 2017). Based on the re-appearance period (RP) at an observation station, Ramp et al.(2004) divided the ISWs into two types:Type-a and Type-b. Type-a ISWs arrive regularly at the same time every day, i.e., the RP is about 24 h, and Type-b ISWs arrive about one hour late every day, i.e., the RP is about 25 h. 展开更多
关键词 SCS A new type of internal solitary waves with a re-appearance period of 23 h observed in the South China Sea
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The Simulation of Five Tropical Cyclones by Sample Optimization of Ensemble Forecasting Based on the Observed Track and Intensity 被引量:2
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作者 Jihang LI Zhiyan ZHANG +3 位作者 Lu LIU Xubin ZHANG Jingxuan QU and Qilin WAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2021年第10期1763-1777,共15页
The quality of ensemble forecasting is seriously affected by sample quality.In this study,the distributions of ensemble members based on the observed track and intensity of tropical cyclones(TCs)were optimized and the... The quality of ensemble forecasting is seriously affected by sample quality.In this study,the distributions of ensemble members based on the observed track and intensity of tropical cyclones(TCs)were optimized and their influence on the simulation results was analyzed.Simulated and observed tracks and intensities of TCs were compared and these two indicators were combined and weighted to score the sample.Samples with higher scores were retained and samples with lower scores were eliminated to improve the overall quality of the ensemble forecast.For each sample,the track score and intensity score were added as the final score of the sample with weight proportions of 10 to 0,9 to 1,8 to 2,7 to 3,6 to 4,5 to 5.These were named as“tr”,“91”,“82”,“73”,“64”,and“55”,respectively.The WRF model was used to simulate five tropical cyclones in the northwestern Pacific to test the ability of this scheme to improve the forecast track and intensity of these cyclones.The results show that the sample optimization effectively reduced the track and intensity error,“55”usually had better performance on the short-term intensity prediction,and“tr”had better performance in short-term track prediction.From the overall performance of the track and intensity simulation,“91”was the best and most stable among all sample optimization schemes.These results may provide some guidance for optimizing operational ensemble forecasting of TCs. 展开更多
关键词 tropical cyclones ensemble forecast sample optimization observed track and intensity
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Pitch Shift in Exsomatized Cochlea Observed by Laser Interferometry 被引量:1
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作者 Zhang-Cai Long Tao Shen +1 位作者 Yan-Ping Zhang Lin Luo 《Chinese Physics Letters》 SCIE CAS CSCD 2019年第2期19-22,共4页
Pitch is one of the most important auditory perception characteristics of sound; however, the mechanism underlying the pitch perception of sound is unclear. Although theoretical researches have suggested that percepti... Pitch is one of the most important auditory perception characteristics of sound; however, the mechanism underlying the pitch perception of sound is unclear. Although theoretical researches have suggested that perception of virtual pitch is connected with physics in cochlea of inner ear, there is no direct experimental observation of virtual pitch processing in the cochlea. By laser interferometry, we observe shift phenomena of virtual pitch in basilar membrane vibration of exsomatized cochlea, which is consistent with perceptual pitch shift observed in psychoacoustic experiments. This means that the complex mechanical vibration of basilar membrane in cochlea plays an important role in pitch information processing during hearing. 展开更多
关键词 In PITCH SHIFT in Exsomatized COCHLEA observed by LASER INTERFEROMETRY
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Improved design of online fault diagnoser for partially observed Petri nets with generalized mutual exclusion constraints 被引量:2
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作者 Jiufu Liu Wenliang Liu +2 位作者 Jianyong Zhou Yan Sun Zhisheng Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第5期971-978,共8页
This paper investigates the fault detection problem for discrete event systems (DESs) which can be modeled by partially observed Petri nets (POPNs). To overcome the problem of low diagnosability in the POPN online fau... This paper investigates the fault detection problem for discrete event systems (DESs) which can be modeled by partially observed Petri nets (POPNs). To overcome the problem of low diagnosability in the POPN online fault diagnoser in current use, an improved online fault diagnosis algorithm that integrates generalized mutual exclusion constraints (GMECs) and integer linear programming (ILP) is proposed. Assume that the POPN structure and its initial markings are known, and the faults are modeled as unobservable transitions. First, the event sequence is observed and recorded. GMEC is used for elementary diagnosis of the system behavior, then the ILP problem of POPN is solved for further diagnosis. Finally, an example of a real DES to test the new fault diagnoser is analyzed. The proposed algorithm increases the diagnosability of the DES remarkably, and the effectiveness of the new algorithm integrating GMEC and ILP is verified. 展开更多
关键词 fault diagnosis partially observed Petri nets (POPNs) integer linear programming (ILP) generalized mutual exclusion constraints (GMECs)
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Glycogen and amyloid-beta: key players in the shift from neuronal hyperactivity to hypoactivity observed in Alzheimer's disease? 被引量:3
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作者 Britanny Bass Sarah Upson +3 位作者 Kamolika Roy Emily L.Montgomery Tuula O.Jalonen Ian V.J.Murray 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第7期1023-1025,共3页
Introduction:Alzheimer’s disease(AD)begins to develop decades prior to its clinical manifestation(Sperling et al.,2011),and while it is the most common form of dementia,as of yet there is no cure.Two of the most... Introduction:Alzheimer’s disease(AD)begins to develop decades prior to its clinical manifestation(Sperling et al.,2011),and while it is the most common form of dementia,as of yet there is no cure.Two of the most researched pathological features contributing to disease development are the extracellular amyloid plaques composed of amyloid-beta proteins(Aβ)and neurofibrillary tangles of tau proteins.Another feature of AD is the progression of early neuronal excitability/hyperactivity to silencing/hypoactivity(Palop and Mucke,2010), 展开更多
关键词 Glycogen and amyloid-beta key players in the shift from neuronal hyperactivity to hypoactivity observed in Alzheimer’s disease
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Observed residual currents off the Changjiang (Yangtze) River mouth in summertime of 1959 and 1982 被引量:1
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作者 朱建荣 戚定满 肖成猷 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2004年第3期250-255,共6页
Data taken in two large scale ocean observations in China in summer 1959 and 1982 were used to analyze the residual current off the Changjiang (Yangtze) River mouth. The currents at surface off the mouth in July 1959 ... Data taken in two large scale ocean observations in China in summer 1959 and 1982 were used to analyze the residual current off the Changjiang (Yangtze) River mouth. The currents at surface off the mouth in July 1959 and 1982 flow northeastward and eastward due to the river discharge, the current speed was larger in1982 than in 1959. All the bottom currents flow landward due to baroclinic effect. The surface current was controlled by the river runoff and the Taiwan Warm Current (TWC). A return current at surface off the mouth was observed in September 1959. In general, the bottom currents were controlled by the TWC in most study area in addition to the runoff near the mouth. Although driven by 3-D model with the monthly averaged forces (river discharge, wind stress, baroclinic effect, open boundary water volume flux and tidal mixing) in August, the simulated circulations were basically consistent with the observed ones with episodic time manner. 展开更多
关键词 off the Changjiang (Yangtze) River mouth observed residual current RUNOFF Taiwan Warm Current
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Unusual Normal and Superconducting State Properties Observed in Hydrothermal Fe_(1-δ)Se Flakes 被引量:1
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作者 Shaobo Liu Sheng Ma +14 位作者 Zhaosheng Wang Wei Hu Zian Li Qimei Liang Hong Wang Yuhang Zhang Zouyouwei Lu Jie Yuan Kui Jin Jian-Qi Li Li Pi Li Yu Fang Zhou Xiaoli Dong Zhongxian Zhao 《Chinese Physics Letters》 SCIE CAS CSCD 2021年第5期109-113,共5页
The electronic and superconducting properties of Fe_(1-δ)Se single-crystal flakes grown hydrothermally are studied by the transport measurements under zero and high magnetic fields up to 38.5 T.The results contrast s... The electronic and superconducting properties of Fe_(1-δ)Se single-crystal flakes grown hydrothermally are studied by the transport measurements under zero and high magnetic fields up to 38.5 T.The results contrast sharply with those previously reported for nematically ordered Fe Se by chemical-vapor-transport(CVT)growth.No signature of the electronic nematicity,but an evident metal-to-nonmetal crossover with increasing temperature,is detected in the normal state of the present hydrothermal samples.Interestingly,a higher superconducting critical temperature T_c of 13.2 K is observed compared to a suppressed T_c of 9 K in the presence of the nematicity in the CVT Fe Se.Moreover,the upper critical field in the zero-temperature limit is found to be isotropic with respect to the field direction and to reach a higher value of-42 T,which breaks the Pauli limit by a factor of 1.8. 展开更多
关键词 red CVT Unusual Normal and Superconducting State Properties observed in Hydrothermal Fe Se Flakes
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Chinese GF-1 and GF-3 satellites observed the giant iceberg calving off the Larsen C Ice Shelf 被引量:1
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作者 SHI Lijian WANG Qimao +1 位作者 ZENG Tao LIANG Chao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第11期115-115,共1页
A massive iceberg, named A-68 by National Ice Center (NIC) officially, calved away from the Larsen C Ice Shelf in Antarctica on luly 12, 2017. The iceberg A-68 is about 5 800 km2, weighs more than a trillion tons an... A massive iceberg, named A-68 by National Ice Center (NIC) officially, calved away from the Larsen C Ice Shelf in Antarctica on luly 12, 2017. The iceberg A-68 is about 5 800 km2, weighs more than a trillion tons and it is one of the biggest ever recorded icebergs. Chinese satellites Gaofen-1 (GF-1) and Gaofen-3 (GF-3) data was used to monitoring the propagation of the rift and the iceberg by National Satellite Ocean Application Service (NSOAS). 展开更多
关键词 GF SAR Chinese GF-1 and GF-3 satellites observed the giant iceberg calving off the Larsen C Ice Shelf Figure
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SAMPLE OPTIMIZATION OF ENSEMBLE FORECAST TO SIMULATE TROPICAL STORMS(MERBOK, MAWAR, AND GUCHOL) USING THE OBSERVED TRACK 被引量:1
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作者 LI Ji-hang GAO Yu-dong +1 位作者 WAN Qi-lin ZHANG Xu-bin 《Journal of Tropical Meteorology》 SCIE 2020年第1期14-26,共13页
Nowadays,ensemble forecasting is popular in numerical weather prediction(NWP).However,an ensemble may not produce a perfect Gaussian probability distribution due to limited members and the fact that some members signi... Nowadays,ensemble forecasting is popular in numerical weather prediction(NWP).However,an ensemble may not produce a perfect Gaussian probability distribution due to limited members and the fact that some members significantly deviate from the true atmospheric state.Therefore,event samples with small probabilities may downgrade the accuracy of an ensemble forecast.In this study,the evolution of tropical storms(weak typhoon)was investigated and an observed tropical storm track was used to limit the probability distribution of samples.The ensemble forecast method used pure observation data instead of assimilated data.In addition,the prediction results for three tropical storm systems,Merbok,Mawar,and Guchol,showed that track and intensity errors could be reduced through sample optimization.In the research,the vertical structures of these tropical storms were compared,and the existence of different thermal structures was discovered.One possible reason for structural differences is sample optimization,and it may affect storm intensity and track. 展开更多
关键词 ensemble forecast sample optimization tropical storm observed track
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The Impact of Directly Observed Therapy on Preventive Treatment for Latent Tuberculosis Infection among Students in Dalian, China 被引量:1
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作者 CHEN Qi WANG Xue Mei +5 位作者 QI Yi LIU Xiao Fang JIANG Li Ping HOU Wen ZHOU Ling LU Xi Wei 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2015年第8期611-615,共5页
Preventive treatment has an essential effect on latent tuberculosis infection(LTBI)[purified protein derivative(PPD)induration≥15 mm].Between2010 and 2013,there were 6 tuberculosis(TB)outbreaks in the universities in... Preventive treatment has an essential effect on latent tuberculosis infection(LTBI)[purified protein derivative(PPD)induration≥15 mm].Between2010 and 2013,there were 6 tuberculosis(TB)outbreaks in the universities in Dalian,China.So far,in Dalian,the directly observed therapy(DOT)and 展开更多
关键词 TB The Impact of Directly observed Therapy on Preventive Treatment for Latent Tuberculosis Infection among Students in Dalian China
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Upper Gastrointestinal Endoscopy at University Hospital Souro Sanou Bobo-Dioulasso (Burkina Faso), about 1022 Cases: Signs and Lesions Observed 被引量:1
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作者 Mali Koura Delphine Passolguewindé Zongo Napon +10 位作者 Zanga Damien Ouattara Kounpiélimé Sosthène Somda Aboubacar Coulibaly Steve Léonce Zoungrana Christine Couna Somé Bere Sandrine Hema Soudré Euloges Bébar Kamboulé Nogogna Zouré Honoré Zougmoré Inoussa Adama Zampou Appolinaire Sawadogo 《Open Journal of Gastroenterology》 2017年第11期287-296,共10页
Upper gastrointestinal endoscopy is an excellent way for the diagnosis of high digestive pathology. We report the results of 1022 upper gastrointestinal endoscopy performed at Bobo-Dioulasso CHU-SS, in western Burkina... Upper gastrointestinal endoscopy is an excellent way for the diagnosis of high digestive pathology. We report the results of 1022 upper gastrointestinal endoscopy performed at Bobo-Dioulasso CHU-SS, in western Burkina Faso (West Africa). The aim of this study was to document the indications and lesions found in high endoscopy at the CHUSS. Patients and Methods: It was a cross-sectional study, prospective to describe the results of gastroscopy performed from 1st January 2015 to 30th June 2016 at the digestive endoscopy unit CHU-Souro Sanou Bobo-Dioulasso. Results: In the study period, 1022 upper gastrointestinal endoscopies were performed. The main indications were: The epigastric pain (48.6%), portal hypertension (10.7%) and gastroesophageal reflux disease (9.9%). The pathologies observed were dominated by gastropathies (48.11%), peptic ulcer (27%) and oesophageal varices (9.68%). Epigastralgias were the main circumstance for the discovery of: 52.3% of esophagitis, 49.17% of gastropathies and 46.12% of peptic ulcers. Histopathologically, the results of the 236 biopsies were dominated by gastritis (88.56%), stomach cancers (7.63%) and esophagus (3.81%). Conclusion: The main indication of the UGIE at the CHU-Souro Sanou in Bobo-Dioulasso was epigastralgia. The pathologies observed were dominated by gastropathy, esophagitis and PUD. 展开更多
关键词 Upper GASTROINTESTINAL ENDOSCOPIC INDICATIONS LESIONS observed Bobo-Dioulasso
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Preliminary Study on the Differences between Automatic-observed and Manual-observed Wind Speed and Its Correction
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作者 张志富 任芝花 范邵华 《Meteorological and Environmental Research》 CAS 2010年第4期1-6,10,共7页
Comparing and analyzing the difference between automatic-observed and manual-observed wind speed based on the wind speed parallel observations in two methods, we find that many elements can influence the difference be... Comparing and analyzing the difference between automatic-observed and manual-observed wind speed based on the wind speed parallel observations in two methods, we find that many elements can influence the difference between automatic-observed and manual-observed wind speed, including the levels of speed wind, observation instruments and different regions. According to these elements, correction has been conducted, and find that the correction according to the level of wind speed has the best correction effect. 展开更多
关键词 Manual observation Automatic observation Level of wind speed Observation instruments China
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INFLUENCE OF CHEMICAL COMPOSITION ON SURFACE BAND BENDING AS OBSERVED THROUGH SURFACE PHOTOVOLTAGE SPECTRA¥
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作者 Jian Feng YU Yan Zhi REN +2 位作者 De Jun WANG Tong Hao WU Yi CUI (Department of Chemistry, Jilin University, Changchun 130023) 《Chinese Chemical Letters》 SCIE CAS CSCD 1994年第4期333-334,共2页
Measurement of the Surface Photovoltage Spectra(SPS) of Mo/Bi series catalysts BixPMo12Oy(x= 2~ 9, y= 43~ 64) showed that with the increase of Bi/P molar ratio, SPS exhibits some changes characteristic of modulated ... Measurement of the Surface Photovoltage Spectra(SPS) of Mo/Bi series catalysts BixPMo12Oy(x= 2~ 9, y= 43~ 64) showed that with the increase of Bi/P molar ratio, SPS exhibits some changes characteristic of modulated surface band bendings. The phenomena were explained in terms of the basic capacity of vacancies in the scheelite-type structure of the catalysts. 展开更多
关键词 AS observed THROUGH BAND BENDING
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THE SECOND LAW ANALYSIS OF GLOBAL IRRADIANCE BASED ON OBSERVED SPECTRAL DISTRIBUTIONS
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作者 曹家枞 《Journal of China Textile University(English Edition)》 EI CAS 1995年第2期22-31,共10页
There have emerged ample literature about the Second Law analysis of extraterrestrial and terrestrial solar radiation consequent to the pioneer works by R. Petela and D. C. Spanner, of which most are irrelevant to the... There have emerged ample literature about the Second Law analysis of extraterrestrial and terrestrial solar radiation consequent to the pioneer works by R. Petela and D. C. Spanner, of which most are irrelevant to the frequency distribution of solar radiation. Since the Second Law analysis was introduced to the fields like photovoltaic and photosynthesis, rendering a need for a method closely related to solar radiation spectrum, some authors created wavelength dependent dilute factots to take the various influence of atmosphere on the frequency distribution into consideration. Because of the complexity of the influence on different frequency, it is not convenient and accurate enough to practically apply the present exergy theories of diluted solar radiation to real solar exergy systems at the surface of the earth. This paper shows a numerical method of Second Law analysis in dealing with the cases of diluted solar irradiance on the earth, based on the observed spectra of global direct and diffuse 展开更多
关键词 Second LAW analysis SOLAR IRRADIANCE observed SPECTRA SOLAR EXERGY system silicon cell
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STUDY ON VARIATION CHARACTERISTICS OF SST OBSERVED IN THE PAST 40 YEARS IN THE COASTAL REGION OF SOUTH CHINA
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作者 潘蔚娟 钱光明 +1 位作者 余克服 陈特固 《Journal of Tropical Meteorology》 SCIE 2007年第2期177-180,共4页
To study the variation characteristics of SST in coastal south China, observed SST was analyzed for the past 44 years. The results show that the monthly and yearly averaged SST have rising trends, the yearly averaged ... To study the variation characteristics of SST in coastal south China, observed SST was analyzed for the past 44 years. The results show that the monthly and yearly averaged SST have rising trends, the yearly averaged SST's linearity rising rate is 0.12-- 0.19 ℃/decade in the years, the rising extents in winter are higher than those in summer. The variability in winter is larger than that in summer, with the largest in February and March. A majority of significant cold or warm events occurred in winter. A wavelet multiresolution method was used to analyze periodical characteristics of SST in coastal south China, all timescale decomposition series are very similar, and high-frequency decompositions within the year are dominant. Low-frequency decompositions show rising trends since the mid-1970. 展开更多
关键词 coastal south China observed SST variation characteristics
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