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| 1 | The reconstruction and interpretations of lake status at 6 ka and 18 ka B.P.in inland mainland Asia显示文摘By means of survey of literature through compilations of sedimentological, biogeological and geomorphologic data, the inland lake level changes in arid or semi arid mainland Asia at 6 and 18 ka B.P. have been reconstructed. The results showed that the lakes from western and northwestern Asia were characterized by very high water levels at 18 ka B.P., but low or intermediate water stands at 6 ka B.P. The high lake level in this region was associated with the southward displacement of westerlies, therefore, the extent of the high lake stand indicated the southern flank of westerlies during the glaciation. Conversely, the lakes from the eastern and southern Asia registered comparative low levels at 18 ka B.P. and significantly high one at 6 ka B.P. The lowering of lake level at 18 ka B.P. was caused by the weakened summer monsoon and the high lake level at 6 ka B.P. by the enhanced summer monsoon induced by the enlarged thermal contrast between land and ocean. The extent of high lake levels indicated the northern boundary of monsoon expansion. Between the above two regions, there is a climatic transitional zone in the Central Asia where the lake behavior was close to that in southeastern Asia at 6 ka B.P. but became similar to that in northwestern Asia at 18 ka B.P. Thus this zone became a transitional sector from the monsoon to the westerlies. | QIN Boqiang 1, SHI Yafeng 1 and YU Ge 2, 3 1. Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences, Nanjing 210008, China 2. Dynamic Palaeoclimatology, Lund University, PO Box 117, S 221 00, Lund, Sweden 3. Department of | 1998 | Chinese Science Bulletin1998，43，14： | 2 |
| 2 | LEACHING OF PRECIOUS METALS FROM COMPLEX SULPHIDE ORES——2.DIRECT LEACHING OF Cu SULFIDE CONCENTRATE BY ACIDIC THIOUREA SOLUTIONS显示文摘Recovery of gold and silver from a sulphide concentrate by thiourea leaching was investigat-ed.The effects of various parameters on the process,such as oxidants,the initial concentrationof thiourea and acidity in solutions as well as reaction temperature,were systematically exam-ined.From the results it was confirmed that(a)oxidants had no significant influence on the dis-solution of gold and silver at a fixed initial concentration of thiourea;(b)the initial concentra-tion of thiourea and acidity affected the dissolution rate only in the earliest period of leaching;(c)the rate of the process was controlled by reagent diffusion.The optimum operations wereworked out for the thiourea leaching process of the concentrate. | Fang,Zhaoheng Institute of Chemical Metallurgy,Academia Sinica,Beijing 100080Muhammed,Mamoun Royal Institute of Technology,S—100044 Stockholm,Sweden | 1993 | 中国有色金属学会会刊:英文版1993，3，4： | 1 |
| 3 | A statistical distribution function of wide applicability显示文摘 | WEIBULL W SWEDEN S | 1951 | Journal of Applied Mechanics1951，，18： | 1 |
| 4 | Thoracic Cross-sectional Imaging of Amvloidosis显示文摘 | Pickford H A Sweden S J Utz J P | 1997 | AJR1997，168，： | 1 |
| 5 | clarifying some fundamental con- cepts in software testing显示文摘 | Parish A S Sweden S H | 1993 | IEEE Transactions on Software Engineering1993，19，7： | 1 |
| 6 | Ipsilateral fracture of the femur and tibia 显示文摘 | KARESTROM G OLERUD S SWEDEN U | 1997 | J Bone Joint Surg Am1997，59，2： | 1 |
| 7 | Long term bending creep of wood in cyclic relative humidity显示文摘 | Mohager S Stockholm Sweden | 1993 | Wood Science and Technology1993，27，： | 1 |
| 8 | A statistical distribution function of wide applicability显示文摘 | SWEDEN S | 1951 | Journal of Applied Mechanics1951，18，3： | 1 |
| 9 | lpsilateral fracture of the femur and tibia显示文摘 | Karlstrom G Olerud S Sweden U | 1977 | J Bone Joint Surg(Am)1977，59，： | 1 |
| 10 | Recording of Monophasic Action Potentials in Swine Using a Modified-tip Platinum Ablation Catheter and Electroanatomical Mapping System(摘要 )显示文摘Objective:In this study, the feasibility to evaluate the global myocardial activation and repolarization sequence using the electroanatomical mapping system and MAP recording technique via the modified platinum catheter was explored in swine. Methods:Ten healthy pigs (50-55 kg) were anaesthetized with pentobarbital and catamine, intubated and ventilated. Four vascular accesses were obtained. A modified small tip ablation catheter (Navi-Star, Biosense Webster), the end surface of tip electrode was 0.81 mm 2 and 1 mm in diameter, was used for MAP recording. The MAP electrograms were recorded between the tip (exploring electrode) and the ring electrode proximal to the tip (indifferent electrode). The catheter was intentionally positioned perpendicular to endocardium with slight contact pressure to allow MAP recording with a satisfactory amplitude and morphology. All MAP recordings were performed during sinus rhythm.Results:The MAP recordings were obtained from both right atrium and left ventricle in 9 pigs, while the right ventricle was mapped during the same procedure in 2. The MAP electrograms were recorded from both right and left atrium via a patent foramen ovale in 1 pig. Totally, the right atrium was mapped in all the 10 pigs, right ventricle in 2, left atrium in 1 and left ventricle in 9. The MAP electrograms were recorded from 733 sites of right atrium, 179 of right ventricle, 63 of left atrium and 517 of left ventricle. There were 62% of right and 54% left atrial MAPamp satisfied the earlier defined criteria of acceptable MAP, i.e., the MAPamp ≥ 3 mV in atrium, while 32% of right and 38% of left ventricular MAPamp were ≥ 10 mV. The mean MAPamp was 5.7±3.1 mV in right atrium, 12.4±2.5 mV in right ventricle, 4.5±1.9 mV in left atrium and 13.8±4 mV in left ventricle. The local activation was more distinctly and easily defined using MAP recordings with the computer-assisted manual determination, so were the end-of-repolarization points. The global activation and repolarization sequence and MAP duration distribution were constructed in all the pigs both in atrium and in ventricle. The activation sequence both in atrium and ventricle could be determined in all pigs three-dimensionally. In the right atrium two preferential inter-nodal conductions were evident, along the crista terminalis and atrial septum from the sinus node area down to the atrioventricular node. Two main connections, Bachman’s bundle and coronary sinus region, constitute the electrophysiologic pathways for right to left atria activation during sinus rhythm. The earliest ventricular activation was located at the high left ventricular septum and followed by radial activation sequence in both ventricles. The posterior base segments of left and right ventricle were activated latest. In the 4 pigs whose chest was opened after sacrifice, no visual detectable injury or bleeding was found in the endocardium and valvular structure. No perforation and no epicardial effusion were observed either.Conclusion: MAP electrograms recorded using the modified platinum catheter were associated with a stable baseline and higher amplitude. MAP recording in difficult areas in all the four chambers of the swine heart was facilitated by the modification of the tip electrode. The construction of the global myocardial activation and repolarization sequence is feasible using the electroanatomical mapping system and MAP recording technique via the modified catheter. The ability to combine MAP recording and spatial information provides a unique tool for both research and clinical electrophysiology. | SHAO Wenliu SHIA Wenyuan Ole Kongstad S Bertil Olsson Department of Cardiology, First Affiliated Hospital of Dalian Medical University. University Hospital, Lund, Sweden | 2002 | 海南医学2002，13，12： | 1 |
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