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sediment loads response to climate change:A preliminary study of eight large Chinese rivers

International Journal of sediment Research 2013年第1期28卷 1-14页

作者： X.X.LU L.s.RAN s.LIU T.JIANG s.R.ZHANG J.J.WANG Department of Geography National University of Singapore117570Singapore Global Change and Watershed Management Center Yunnan University of Finance and EconomicsYunnan National Climate Centre China Meteorological AdministrationBeijingChina College of Water sciences Beijing Normal UniversityChina

Climate change characterized by increasing temperature is able to affect precipitation regime and thus surface ***,the manner in which river sediment loads respond to climate change is not well understood,and related assessment regarding the effect of climate change on sediment loads is *** present a quantitative estimate of changes in sediment loads(from 1.5 Gt yr-1pre-1990 to 0.6 Gt yr-1from 1991-2007) in response to climate change in eight large Chinese *** the past decades,precipitation change coupled with rising temperatures has played a significant role in influencing the sediment delivery dynamics,although human activities, such as reservoir construction,water diversion,sand mining and land cover change,are still the predominant forces. Lower precipitation coupled with rising temperatures has significantly reduced sediment loads delivered into the sea in semi-arid climates(4-61%).In contrast,increasingly warmer and wetter climates in subtropical zones has yielded more sediment(0.4-11%),although the increase was offset by human *** results indicate that,compared with mechanical retention by reservoirs,water reduction caused by climate change or human withdrawals has contributed more sediment reduction for the rivers with abundant sediment supply but limited transport capacity(e.g.,the Huanghe).Furthermore,our results indicate that every 1%change in precipitation has resulted in a 1.3%change in water discharge and a 2%change in sediment *** addition,every 1%change in water discharge caused by precipitation has led to a 1.6%change in sediment loads,but the same percentage of water discharge change caused largely by humans would only result in a 0.9%change in sediment *** figures can be used as a guideline for evaluating the responses of sediment loads to climate change in similar climate zones because future global warming will cause dramatic changes in water and sediment in river basins worldwide at rates previou

关键词： sediment load Climate change Human activity Water withdrawal Chinese rivers

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Machine learning in endoscopic ultrasonography and the pancreas:The new frontier?

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Artificial Intelligence in Gastroenterology 2022年第2期3卷 54-65页

作者： Cem simsek Linda s Lee Department of Gastroenterology Hepatology and EndoscopyDepartment of MedicineBrigham and Women's HospitalHarvard Medical SchoolBostonMA 02215United States Division of Gastroenterology Hepatology and EndoscopyDepartment of MedicineBrigham and Women's HospitalHarvard Medical SchoolBostonMA 02115United States

Pancreatic diseases have a substantial burden on society which is predicted to increase further over the next *** ultrasonography(EUs)remains the best available diagnostic method to assess the pancreas,however,there remains room for *** intelligence(AI)approaches have been adopted to assess pancreatic diseases for over a decade,but this methodology has recently reached a new era with the innovative machine learning algorithms which can process,recognize,and label endosonographic *** review provides a targeted summary of AI in EUs for pancreatic *** studies cover a wide spectrum of pancreatic diseases from pancreatic cystic lesions to pancreatic masses and diagnosis of pancreatic cancer,chronic pancreatitis,and autoimmune *** these,AI models seemed highly successful,although the results should be evaluated carefully as the tasks,datasets and models were greatly *** addition to use in diagnostics,AI was also tested as a procedural real-time assistant for EUs-guided biopsy as well as recognition of standard pancreatic stations and labeling anatomical landmarks during routine *** thus far have suggested that the adoption of AI in pancreatic EUs is highly promising and further opportunities should be explored in the field.

关键词： Artificial intelligence Pancreas Endoscopic ultrasonography Pancreatic cancer Autoimmune pancreatitis Pancreatic cystic lesions

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soil Development and Fertility Characteristics of Inland Valleys in the Rain Forest Zone of Nigeria: Mineralogical Composition and Particle-size Distribution

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Pedosphere 2009年第4期19卷 505-514页

作者： s. s. ABE G. O. OYEDIRAN T. MAsUNAGA s. YAMAMOTO T. HONNA T. WAKATsUKI Africa Rice Center (WARDA) Faculty of Agriculture Tottori University Department of Agronomy Ladoke Akintola University of Technology Ogbamoso (Nigeria) Faculty of Life and Environmental science Shimane University Faculty of Agriculture Kinki University

The particle-size distribution and mineralogical composition of the clay (< 2 μm) and fine-sand (0.25-0.10 mm) fractions in soils of two inland valleys in Abakaliki and Bende, southeast Nigeria, were investigated to ... 详细信息

The particle-size distribution and mineralogical composition of the clay (sand (0.25-0.10 mm) fractions in soils of two inland valleys in Abakaliki and Bende, southeast Nigeria, were investigated to provide basic information on soil-forming processes and agricultural potentials. These soils were silty or clayey, deriving from Cretaceous or Tertiary shale materials. The particle-size distribution and its computation on a clay-free basis revealed relatively remarkable lithologic breaks in a couple of pedons. The effect of lithologic discontinuities on soil mineralogical composition was not, however, conspicuous. Petrographic investigation revealed that quartz predominantly comprised the fine-sand fraction in the soils at both study sites. Nevertheless, the clay mineralogical composition of the soils was a mixture of kaolinite, irregularly interstratified smectite-illite intergrades (s/I), hydroxyl-Al interlayered 2:1 type clays (HICs), vermiculite, smectite, halloysite and illite along with fine-sized quartz in Abakaliki. The soils of Bende predominantly contained smectite, which was partially interlayered with hydroxyl-Al and kaolinite. It is suggested that seasonal floodwater has slowed the disintegration of weatherable clay minerals inherited from the shale, while quartz originating from the sandstone is predominant in the fine-sand fraction. Additionally, a possible soil-forming process observed at the both study sites was ferrolysis, which was indicated by a clear decreasing pattern of HICs downward in the soil profiles. The entry of s/I and vertical distribution patterns for a couple of clay minerals in the pedon suggested that the soils in Abakaliki have developed under the significant influence of aeolian dust delivered by the Harmattan. The findings might describe a site-specific deposition pattern of Harmattan dusts as well as hydromorphic soil-forming processes in the wetlands of the inland valleys.

关键词：粒度分布矿物成分尼日利亚生育特性土壤发育林区山谷内陆

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Current updates and future directions in diagnosis and management of gastroenteropancreatic neuroendocrine neoplasms

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World Journal of Gastrointestinal Endoscopy 2022年第5期14卷 267-290页

作者： andrew Canakis Linda s Lee Division of Gastroenterology and Hepatology University of Maryland School of MedicineBaltimoreMD 21201United States Division of Gastroenterology Hepatology and Endoscopy Brigham and Women's HospitalHarvard Medical SchoolBostonMA 02115United States

Gastroenteropancreatic neuroendocrine neoplasms are a heterogenous group of rare neoplasms that are increasingly being discovered,often incidentally,throughout the gastrointestinal tract with varying degrees of activity and malignant *** nomenclature has added to the complexity of managing these *** term carcinoid tumor and embryonic classification have been replaced with gastroenteropancreatic neuroendocrine neoplasm,which includes gastrointestinal neuroendocrine and pancreatic neuroendocrine neoplasms.A comprehensive multidisciplinary approach is important for clinicians to diagnose,stage and manage these *** histological diagnosis is the gold standard,recent advancements in endoscopy,conventional imaging,functional imaging,and serum biomarkers complement histology for tailoring specific treatment *** light of developing technology,our review sets out to characterize diagnostic and therapeutic advancements for managing gastroenteropancreatic neuroendocrine tumors,including innovations in radiolabeled peptide imaging,circulating biomarkers,and endoscopic treatment approaches adapted to different locations throughout the gastrointestinal system.

关键词： Gastroenteropancreatic neuroendocrine neoplasms Neuroendocrine tumors Neuroendocrine carcinoma Gastrointestinal Pancreas small intestine

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ABsTRACTs

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学习与探索 2018年第1期 174-176页

作者： ’s

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synthesis and electrochemical properties of environmental free Lglutathione grafted graphene oxide/ZnO nanocomposite for highly selective piroxicam sensing

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Journal of Pharmaceutical Analysis 2021年第1期11卷 48-56页

作者： N.Dhanalakshmi T.Priya s.Thennarasu s.sivanesan N.Thinakaran Environmental Research Lab PG and Research Department of ChemistryAlagappa Government Arts CollegeKaraikudi630003Tamil NaduIndia school of Chemistry Bharathidasan UniversityThiruchirapalli620024Tamil NaduIndia Department of Applied science and Technology AC TechAnna UniversityChennai25India

A simple and reliable strategy was proposed to engineer the glutathione grafted graphene oxide/ZnO nanocomposite(glutathione-GO/ZnO)as electrode material for the high-performance piroxicam *** prepared glutathione-GO/ZnO nanocomposite was well characterized by X-ray diffraction(XRD),Fourier transform infrared spectrum(FTIR),X-ray photoelectron spectroscopy(XPs),field emission scanning electron microscopy(FE-sEM),cyclic voltammetry(CV),electrochemical impedance spectroscopy(EIs)and differential pulse voltammetry(DPV).The novel nanocomposite modified electrode showed the highest electrocatalytic activity towards piroxicam(oxidation potential is 0.52 V).Under controlled experimental parameters,the proposed sensor exhibited good linear responses to piroxicam concentrations ranging from 0.1 to 500 μ*** detection limit and sensitivity were calculated as 1.8 μM and 0.2 μA/μM·cm^(2),***,it offered excellent selectivity,reproducibility,and long-term stability and can effectively ignore the interfering candidates commonly existing in the pharmaceutical tablets and human fluids even at a higher ***,the reported sensor was successfully employed to the direct determination of piroxicam in practical samples.

关键词： Reduced graphene oxide Glutathione ZnO Piroxicam Electrochemical sensing

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Intra-Articular Distal Radius Fracture with Lunate Fossa Rotated and Associated Lesions:Radiologic Analysis

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Open Journal of Orthopedics 2023年第4期

作者： Issam Ait Hadj sliman Cesar Tommeh Frederic Desmoulin andré-Pierre Uzel

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Experimental study of human-induced effects on floor slab of an ancient Tibetan structure

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Earthquake Engineering and Engineering Vibration 2012年第4期11卷 513-523页

作者： Yang Na Guo Ting s.s. Law school of Civil Engineering Beijing Jiaotong University Civil and structural Engineering Department Hong Kong Polytechnic University

With the opening of ancient Tibetan structures to visitors worldwide, human load has become the principal live load on these structures. This project studies the properties of the floor structure of an ancient Tibetan building and its behavior under human-induced load effects. Tests were conducted with static and dynamic crowd load, including stepping and jogging by people at a fixed position. The tests show that the floor structure does not behave as a continuous slab. It takes the load from local areas with minimal load transference properties. The acceleration response shows significant peaks when the footstep frequency is close to the natural frequency of the s~＇ucture, but the human jogging excitation frequency does not have any obvious effect on the structural response. The elastic modulus of the Agatu material is estimated to be close to zero from the measured natural frequency of the slab. The Agatu material is concluded to be a discrete compacted material with insignificant contribution to the structural rigidity of the floor slab.

关键词： ancient Tibetan structure crowd load static dynamic floor slab Agatu elastic modulus

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THE ELECTROCHEMICAL BEHAVIOR OF OCEANIC MICROBIOLOGICAL INFLUENCED CORROsION ON CARBON sTEEL

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Acta Metallurgica sinica(English Letters) 2007年第5期20卷 334-340页

作者： X.T. Chang Y.s. Yin G.H. Niu T. Liu s. Cheng s.B. sun Institute of Materials science and Technology Ocean University of China Qingdao 266003 China College of Materials science and Technology Shandong University Jinan 250061 China

The corrosion behavior of carbon steel in the medium of marine microorganisms was investigated by electrochemical impedance spectra, polarization curves, and so on. Experimental results showed that the corrosion potential of carbon steel moved in a negative direction in the unpurified marine microorganism solution, and the polarization style of the cathodic process did not change. The electrochemical impedance spectra showed that the impedance value of the electrode decreased in the medium with bacteria, which indicated that the existence of microorganism could accelerate the corrosion progress of carbon steel.

关键词： carbon steel microbiological influenced corrosion polarization curve electrochemical impedance spectroscopy

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Quantification by allometric equations of carbon sequestered by Tectona grandis in different agroforestry systems

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Journal of Forestry Research 2013年第4期24卷 699-702页

作者： Avinash Jain s.A.Ansari Tropical Forest Research Institute

Non destructive methods for quantification of carbon seques- tration in tropical trees are inadequately developed. We described a stan- dardized method for estimating carbon stock in teak （Tectona grandis Linn. F.）. We developed linear allometric equations using girth at breast height （GBH）, height and age to quantify above ground biomass （AGB）. We used AGB to estimate carbon stock for teak trees of different age groups （1.5, 3.5, 7.5, 13.5, 18.5 and 23.5 years）. The regression equation with GBH, y = 3.174x - 21.27, r2=0.898 （p 〈0.01）, was found precise and convenient due to the difficulty in determination of height and age in dense natural forests of teak. The equation was evaluated in teak agroforestry systems that included Triticum aestivum （wheat）, Cicer arietinum （gram）, Withania somnifera （ashwagandha）,

关键词： Tectona grandis agroforestry system allometric equation carbon sequestration above ground biomass

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