917 resultados para giant panda


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Zooplankton plays a vital role in marine ecosystems. Variations in the zooplankton species composition, biomass, and secondary production will change the structure and function of the ecosystem. How to describe this process and make it easier to be modeled in the Yellow Sea ecosystem is the main purpose of this paper. The zooplankton functional groups approach, which is considered a good method of linking the structure of food webs and the energy flow in the ecosystems, is used to describe the main contributors of secondary produciton of the Yellow Sea ecosystem. The zooplankton can be classified into six functional groups: giant crustaceans, large copepods, small copepods, chaetognaths, medusae, and salps. The giant crustaceans, large copepods, and small copepods groups, which are the main food resources for fish, are defined depending on the size spectrum. Medusae and chaetognaths are the two gelatinous carnivorous groups, which compete with fish for food. The salps group, acting as passive filter-feeders, competes with other species feeding on phytoplankton, but their energy could not be efficiently transferred to higher trophic levels. From the viewpoint of biomass, which is the basis of the food web, and feeding activities, the contributions of each functional group to the ecosystem were evaluated; the seasonal variations, geographical distribution patterns, and species composition of each functional group were analyzed. The average zooplankton biomass was 2.1 g dry wt m(-2) in spring, to which the giant crustaceans, large copepods, and small copepods contributed 19, 44, and 26%, respectively. High biomasses of the large copepods and small copepods were distributed at the coastal waters, while the giant crustaceans were mainly located at offshore area. In summer, the mean biomass was 3.1 g dry wt m(-2), which was mostly contributed by the giant crustaceans (73%), and high biomasses of the giant crustaceans, large copepods, and small copepods were all distributed in the central part of the Yellow Sea. During autumn, the mean biomass was 1.8 g dry wt m(-2), which was similarly constituted by the giant crustaceans, large copepods, and small copepods (36, 33, and 23%, respectively), and high biomasses of the giant crustaceans and large copepods occurred in the central part of the Yellow Sea, while the small copepods were mainly located at offshore stations. The giant crustaceans and large copepods dominated the zooplankton biomass (2.9 g dry wt m(-2)) in winter, contributing respectively 57 and 27%, and they, as well as the small copepods, were all mainly located in the central part of the Yellow Sea. The chaetognaths group was mainly located in the northern part of the Yellow Sea during all seasons, but contributed less to the biomass compared with the other groups. The medusae and salps groups were distributed unevenly, with sporadic dynamics, mainly along the coastline and at the northern part of the Yellow Sea. No more than 10 species belonging to the respective functional groups dominated the zooplankton biomass and controlled the dynamics of the zooplankton community. The clear picture of the seasonal and spatial variations of each zooplankton functional group makes the complicated Yellow Sea ecosystem easier to be understood and modeled. (C) 2010 Elsevier Ltd. All rights reserved.

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Six species belonging to two families of Hemichordata have previously been recorded in Chinese waters. This paper records the discovery and description of a new species of the genus Glandiceps found in Jiaozhou Bay, Qingdao, Shandong Province, named Glandiceps qingdaoensis. The new species has a long proboscis with dorsal and ventral grooves, a stomochord with a long vermiform process, a proboscis cavity with a dorsal median, right and left glomeruli, right and left glomeruli very large and encircling the stomochord, a proboscis skeleton in the cavity extends into the median posterior of the collar, a well-developed dorsal ventral muscular septum in the proboscis cavity dividing the cavity completely into two separate parts. The collar cord is without giant nerve roots. The trunk with four distinct regions that can be recognized externally: branchial-genital region, genital region, hepatic region, and intestinal region. The dorsal pharynx is large and the gill pores are small. The tongue bars are encircled by vesicles, and the first gonad commences at the level of the second or third gill slit.

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In practice,many fracture reservoir was found,which has giant potential for exporation. For example,in limestone fracture reservoir,igneous rock fracture reservoir and shale fracture reservoir ,there are high yield oil wells found. The fracture reservoir has strong anisotropy and is very difficult to explore and produce.Since 1990’s,the techniques that use structure information and P-WAVE seismic attributes to detect fracture developed very rapidly,include stress and strain analysis,using amplitude,interval velocity,time-difference,azimuthal AVO analysis etc. Based on research and develop these advanced techniques of fracture detect,this paper selected two typical fracture reservoir as target area,according to the characters of research area,selected different techniques to pridect the fracture azimuth and density of target,and at last ,confirmed the favored area. This paper includes six parts:the first chapter mainly addresses the domestic and international research actuality about the fracture prediction and the evolement in ShengLi oil field,then according to the temporal exploration requirement,a research route was established; Based on the close relationship between structural fracture and the geotectonic movement and the procedure of rock distortion,the second chapter research the structural fracture predicting technique which is realized by computing the strain in every geotectonic movement ,which is by use of the forward and inversion of the growing history of structure; The third chapter discussed many kind of traditional techniques for fracture reservoir prediction,and point out their disadvantages.then research and develop the coherence volume computing technique which can distinguish from faults,the seismic wave absorbing technique,and other fracture predicting technique which is by use of seismic attributes ,such as azimuthal AVO FVO etc; The fourth chapter first establish the geological and petrophysical model by use of the existed log and drill well information, then research the variation of amplitude and seismic wave which is caused by fractures.based on it , the fracture predicting technique which is by use of variation of azimuthal impedance is researched;The fifth chapter is a case study,it selects shale fracture reservoir in LuoJia area as target,selects several kind of techniques to apply ,at last ,the fracture distribution of target reservoir and favored area were gotten;the sixth chapter is another case study,it selects limestone fracture reservoir in BoShen6 buried hill as target,selects several kind of techniques to apply,similarly favored area were gotten. Based on deeply research and development of the new techniques for fracture reservoir exploration, This paper selects two fracture reservoirs the most typical in ShengLi as targets to be applied ,good results show up a good application way ,which can be used for reference for future fracture exploration,and it can bring materially economic and social benefit.

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Sulige Gasfield, with a basically proven reserve as high as one trillion cubic meters, is one giant gas field discovered in China. The major gas -bearing layers are Upper Paleozoic strata with fluvial-lacustrine sedimentary facies. Generally, gas reservoirs in this field are characteristic by "five low" properties, namely low porosity, low permeability, low formation pressure, low productivity and low gas abundance. Reservoirs in this field also feature in a large distribution area, thin single sandbody thickness, poor reservoir physical properties, thin effective reservoir thickness, sharp horizontal and/or vertical changes in reservoir properties as well as poor connectivity between different reservoirs. Although outstanding achievements have been acquired in this field, there are still several problems in the evaluation and development of the reservoirs, such as: the relation between seismic attributes and reservoir property parameters is not exclusive, which yields more than one solution in using seismic attributes to predict reservoir parameters; the wave impedance distribution ranges of sandstone and mudstone are overlapped, means it is impossible to distinguish them through the application of post-stack impedance inversion; studies on seismic petrophysics, reservoir geophysical properties, wave reflection models and AVO features have a poor foundation, makes it difficult to recognize the specific differences between tight sandstone and gas-bearing sandstone and their distribution laws. These are the main reasons causing the low well drilling success rate and poor economic returns, which usually result in ineffective development and utilization of the field. Therefore, it is of great importance to perform studies on identification and prediction of effective reservoirs in low permeable sandstone strata. Taking the 2D and 3D multiwave-multicomponent seismic exploration block in Su6-Su5 area of Sulige field as a study area and He 8 member as target bed, analysis of the target bed sedimentary characteristics and logging data properties are performed, while criteria to identify effective reservoirs are determined. Then, techniques and technologies such as pre-stack seismic information (AVO, elastic impedance, wave-let absorption attenuation) and Gamma inversion, reservoir litological and geophysical properties prediction are used to increase the precision in identifying and predicting effective reservoirs; while P-wave and S-wave impedance, ratio of P/S wave velocities, rock elastic parameters and elastic impedance are used to perform sandstone gas-bearing property identification and gas reservoir thickness prediction. Innovative achievements are summarized as follows: 1. The study of this thesis is the first time that multiwave-multicomponent seismic data are used to identify and predict non-marine classic reservoirs in China. Through the application of multiwave-multicomponents seismic data and integration of both pre-stack and post-stack seismic data, a set of workflows and methods to perform high-precision prediction of effective reservoirs in low permeable sandstone is established systematically. 2. Four key techniques to perform effective reservoir prediction including AVO analysis, pre-stack elastic wave impedance inversion, elastic parameters inversion, and absorption attenuation analysis are developed, utilizing pre-stack seismic data to the utmost and increasing the correct rate for effective reservoir prediction to 83% from the former 67% with routine methods. 3. This thesis summarizes techniques and technologies used in the identification reservoir gas-bearing properties using multiwave-multicomponent seismic data. And for the first time, quantitative analysis on reservoir fluids such as oil, gas, and/or water are carried out, and characteristic lithology prediction techniques through the integration of pre-stack and post-stack seismic prediction techniques, common seismic inversion and rock elastic parameters inversion, as well as P-wave inversion and converted wave inversion is put forward, further increasing the correct rate of effective reservoir prediction in this area to 90%. 4. Ten seismic attribute parameters are selected in the 3D multi-wave area to perform a comprehensive evaluation on effective reservoirs using weighted-factor method. The results show that the first class effective reservoir covers an area of 10.08% of the study area, while the second and the third class reservoirs take 43.8% and 46% respectively, sharply increasing the success rate for appraisal and development wells.

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Bayan Obo giant REE-Nb-Fe deposit in the northen margin of the North China Craton (NCC) is well known in the world for its abundant rare earth element resources. There is nearly one hundred year of studying history in substance component, chronology and geochemistry of the ore deposit, since the main ore body was found in 1927. However, there still exist remarkable divergences in genesis, mineralized age and material origin. Especially the REE enrichment mechanism leaves us a secret. Recent research shows that the Bayan Obo ore deposit likely resulted from the carbonatite magma activity, which is a favorable factor for REE accumulation. Based on the analysis of tectonic evolution history of north margin of NCC this thesis mainly discussed the formation background of cratonic margined rifts in Bayan Obo, and presented the analytical results of formation environment, intrusion age and deep origin of Proterozoic carbonatite magma. These research results can provide evidence for ore genesis. LA ICP-MS U-Pb dating on zircon shows that the Neoarchean basement was mainly composed of calc-alkaline TTG gneisses (2588±16Ma). The collision orogeny movement of the northen margin of the NCC between 2.0 Ga to 1.9 Ga brought the swarm of diorite-granodiotite magma (2023±16Ma) and intense regional metamorphism event (1906.3±7.7 Ma to 1892.7±6.7 Ma). In the sequent super continent break up background, intense metamorphic and deformed basement complex was uplifted to the surface suffered denudation, forming Mesoproterozoic Bayan Obo group in the contemporary continental margin rifts. The uplift of basement complex and formation of continental rifts were likely related with mantle plume activity. Evidence from petrological and geochemical data suggests that abundant alkaline-basic magma resulted from enhancement of continental breakup activity, that separated into carbonatite veins and mafic dykes by melt immiscibility mechanism, intruded in Bayan Obo margin rifts at the late stage of extension movement. Carbonatite veins can be divided into three main types by mineral composition: dolomite carbonatite, dolomite-calcite coexistent carbonatite and calcite carbonatite. Intrusion relationship between different types of carbonatite veins show that the calcite carbonatite veins were formed latter than the dolomite type as well as the coexistent type. Moreover, geochemical data also reveals successive and evolutive character between them. The content of REE increases together with the calcite minerals component. That is to say that REE gradually accumulated as the evolution of carbonatite magma. High precision Sm-Nd isochron data shows that the intrusion age of carbonatite veins was at 1319±48Ma. Moreover, the REE mineralization age in calcite carbonatite veins was around 1275±87Ma that is consistent with the intrusion age in error range. According to these data the abundant REE already existed in the carbonatite magma before intrusion and result in the earlier ore mineralization. The average age of mineralized dolomite was at 1353±100Ma, and the mineralization age of apatite in coarse grain dolomite was around 1329±150Ma. These data is consistent with carbonatite. Considering the coincident rare, trace element and isochron composition between them, it is presumed that mineralized dolomite was also the carbonatite intrusion and was the mainly factor for huge REE enrichment.

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Bayan Obo REE-Nb-Fe ore deposit is the largest REE deposit in the world. Owing to its unique type and tremendous economic value, this deposit has widely attracted interests from geological researchers and vast amount of scientific data have been accumulated. However, its genesis, especially ore-forming age and REE sources, have been under dispute for a long time. On the basis of previous research works, this paper mainly conducts studies on the Early Paleozoic ore-forming event in the Bayan Obo deposit. The following results and conclusions can be suggested: Sm-Nd isotopic analytical results of bastnaesite, beloeilite, albite and fluorite samples from a coarse-crystalline ore lode present an isochron age of 436±35Ma. Besides, Rb-Sr isotope dating of the coarse-crystalline biotite lode that intruded into banded ores gives an isochron age of 459±39Ma. The two ages verify the exist of Early Paleozoic ore-forming event at Bayan Obo, which characterized by extensive netted mineralization of REE fluorocarbonates, aeschynite and monazite, accompanied by widely fluorite-riebeckite-aegirine-apatite alteration. Sr-Nd isotope composition of vein minerals is located between EMI and ancient lower crust component in the ISr(t)-εNd(t) correlation diagram, indicating that there is a crustal contamination during veined mineralization. A large area late Paleozoic granitoids are distributed in the southeast region of east open pit of the mine. The granitoids intruded directly into the ore-bearing dolomite, and produced intense skarnization. Moreover, at 650-660m of the drill core on 22 line and 1598m level flat in the south of East Open Pit, we firstly found skarnization rocks. Single grain and low background Rb-Sr isochrone dating on phlogopite in skarn gives 309±12Ma. Considering the intruded contacting relationship, the late Paleozoic granitoids, already extended to the under part of REE ore bodies, must be posterior to the latest intense REE mineralization, and is only a destructive tectonic and magmatic activity. Fluid inclusion types of fluorite in the Bayan Obo deposit consist of multiphase daughter mineral-bearing inclusion, two or three phase CO2-bearing inclusion and two phase aqueous inclusion. Petrography, laser Raman analysis and microthermometry study indicate that the fluids involving in REE-Nb-Fe mineralization at Bayan Obo might be mainly of H2O-CO2-NaCl-(F-REE) system. The presence of REE-carbonate as a daughter mineral in fluid inclusions shows that the original ore-forming fluids are rich in REE elements.

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Large earthquakes, such as the Chile earthquake in 1960 and the Sumatra-Andaman earthquake on Dec 26, 2004 in Indonesia, have generated the Earth’s free oscillations. The eigenfrequencies of the Earth’s free oscillations are closely related to the Earth’s internal structures. The conventional methods, which mainly focus on calculating the eigenfrequecies by analytical ways, and the analysis on observations can not easily study the whole processes from earthquake occurrence to the Earth’s free oscillation inspired. Therefore, we try to use numerical method incorporated with large-scale parallel computing to study on the Earth’s free oscillations excited by giant earthquakes. We first give a review of researches and developments of the Earth’s free oscillation, and basical theories under spherical coordinate system. We then give a review of the numerical simulation of seismic wave propagation and basical theories of spectral element method to simulate global seismic wave propagation. As a first step to study the Earth’s free oscillations, we use a finite element method to simulate the propagation of elastic waves and the generation of oscillations of the chime bell of Marquis Yi of Zeng, by striking different parts of the bell, which possesses the oval crosssection. The bronze chime bells of Marquis Yi of Zeng are precious cultural relics of China. The bells have a two-tone acoustic characteristic, i.e., striking different parts of the bell generates different tones. By analysis of the vibration in the bell and the spectrum analysis, we further help the understanding of the mechanism of two-tone acoustic characteristics of the chime bell of Marquis Yi of Zeng. The preliminary calculations have clearly shown that two different modes of oscillation can be generated by striking different parts of the bell, and indicate that finite element numerical simulation of the processes of wave propagation and two-tone generation of the chime bell of Marquis Yi of Zeng is feasible. These analyses provide a new quantitative and visual way to explain the mystery of the two-tone acoustic characteristics. The method suggested by this study can be applied to simulate free oscillations excited by great earthquakes with complex Earth structure. Taking into account of such large-scale structure of the Earth, small-scale low-precision numerical simulation can not simply meet the requirement. The increasing capacity in high-performance parallel computing and progress on fully numerical solutions for seismic wave fields in realistic three-dimensional spherical models, Spectral element method and high-performance parallel computing were incorporated to simulate the seismic wave propagation processes in the Earth’s interior, without the effects of the Earth’s gravitational potential. The numerical simulation shows that, the results of the toroidal modes of our calculation agree well with the theoretical values, although the accuracy of our results is much limited, the calculated peaks are little distorted due to three-dimensional effects. There exist much great differences between our calculated values of spheroidal modes and theoretical values, because we don’t consider the effect the Earth’ gravitation in numerical model, which leads our values are smaller than the theoretical values. When , is much smaller, the effect of the Earth’s gravitation make the periods of spheroidal modes become shorter. However, we now can not consider effects of the Earth’s gravitational potential into the numerical model to simulate the spheroidal oscillations, but those results still demonstrate that, the numerical simulation of the Earth’s free oscillation is very feasible. We make the numerical simulation on processes of the Earth’s free oscillations under spherically symmetric Earth model using different special source mechanisms. The results quantitatively show that Earth’s free oscillations excited by different earthquakes are different, and oscillations at different locations are different for free oscillation excited by the same earthquake. We also explore how the Earth’s medium attenuation will take effects on the Earth’s free oscillations, and take comparisons with the observations. The medium attenuation can make influences on the Earth’s free oscillations, though the effects on lower-frequency fundamental oscillations are weak. At last, taking 2008 Wenchuan earthquake for example, we employ spectral element method incorporated with large-scale parallel computing technology to investigate the characteristics of seismic wave propagation excited by Wenchuan earthquake. We calculate synthetic seismograms with one-point source model and three-point source model respectively. Full 3-D visualization of the numerical results displays the profile of the seismic wave propagation with respect to time. The three-point source, which was proposed by the latest investigations through field observation and reverse estimation, can better demonstrate the spatial and temporal characteristics of the source rupture processes than one-point source. Primary results show that those synthetic signals calculated from three-point source agree well with the observations. This can further reveal that the source rupturing process of Wenchuan earthquake is a multi-rupture process, which is composed by at least three or more stages of rupture processes. In conclusion, the numerical simulation can not only solve some problems concluding the Earth’s ellipticity and anisotropy, which can be easily solved by conventional methods, but also finally solve the problems concluding topography model and lateral heterogeneity. We will try to find a way to fully implement self-gravitation in spectral element method in future, and do our best to continue researching the Earth’s free oscillations using the numerical simulations to see how the Earth’ lateral heterogeneous will affect the Earth’s free oscillations. These will make it possible to bring modal spectral data increasingly to bear on furthering our understanding of the Earth’s three-dimensional structure.

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Sangequan Uplift in Junggar Basin is an inherited positive structure, which has undergone many times of violent tectonic movements, with high tectonic setting, and far away from the oil-source sag, reservoir forming condition is complex. Combining sequence stratigraphy, depositional facies, reservoir formation theory with seismic and well logging analysis, this paper conducted integrated study on the hydrocarbon migration, accumulation, entrapment conditions, the reservoir forming dynamics and the forming model, and acquired the following recognition: (1) The special reservoir formation conditions that enable Sangequan Uplift to form a giant oil-gas field of over 100 million tons of reserves are as follows: (D Deltaic frontal sandbody is developed in Jurassic Xishanyao Formation, Toutunhe Formation and Lower Cretaceous Hutubihe Formation, with good reservoir quality;? Abundant hydrocarbon resources are found in Western Well Pen-1 Sag, which provides sufficient oil sources for reservoir formation of Sagequan Uplift; ?The unconformity-fault-sandbody system has formed a favorable space transporting system and an open conduit for long-distance hydrocarbon migration; ?fault, low amplitude anticline and lithological traps were well developed, providing a favorable space for hydrocarbon accumulation. (2) The most significant source beds in the Western Well Pen-1 Sag are the Mid-Permian Lower Wuerhe Formation and Lower-Permian Fengcheng Formation. The oil in the Well Block Lu-9 and Shinan Oilfield all originated from the hydrocarbon source beds of Fengcheng Formation and Lower Wuerhe Formation in the Western Well Pen-1 Sag and migrated through Jidong and Jinan deep faults linking unconformity of different regions from sources to structural highs of the uplift and shallow horizons. (3) There were 2 reservoir formation periods in District Sangequan: the first was in late Cretaceous during which the upper part of Xishanyao Formation and Toutunhe Formation; the second was in Triassic, the main resources are high-maturity oil and gas from Fengcheng Formation and Wuerhe Formation in Western Pen-1 Well sag and the gas from coal measure strata of Xishanyao Formation, that were accumulated in Hutubihehe Formation. (4) Model of the hydrocarbon migration, accumulation, reservoir formation of the study area are categorized as three types starting from the hydrocarbon source areas, focusing on the faults and unconformity and aiming at reservoirs: ① Model of accumulation and formation of reservoir through faults or unconformities along the "beam" outside source; ②Model of migration, accumulation and reservoir formation through on-slope near source;③Model of migration, accumulation and reservoir formation of marginal mid-shallow burial biogas-intermediate gas. (5) Pinchout, overlap and lithologic traps are developed in transitional zones between Western Well Pen-1 sag and Luliang uplift. Many faulted blocks and faulted nose-like traps are associated with large structures on Sangequan uplift. Above traps will be new prospecting areas for further hydrocarbon exploration in future.

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The research area of this paper covers the maximum exploration projects of CNPC, including Blocks 1/2/4 and Block 6 of the Muglad basin and the Melut basin in Bocks 3/7 in Sudan. Based on the study of the evolution history of the Central African Shear Zone (CASZ), structural styles and filling characteristics of the rift basins, it is put forward that the rift basins in Sudan are typical passive rift basins undergoing the strike-slip, extension, compression and inversion since the Cretaceous. The three-stage rift basins overlapped obliquely. The extension and rifting during the Early Cretaceous is 50-70% of the total extension. The features of the passive rift basins decided that there is a single sedimentary cycle and one set of active source rocks within the middle. Influenced by the three-stage rifting and low thermal gradient, hydrocarbon generation and charging took place very late, and the oil pool formation mechanism is very unique from the Lower Cretaceous rift sequences to the Paleogene. The reservoir-seal assemblages are very complicated in time and space. The sealing capacity of cap rocks was controlled by the CASZ. In general the oils become heavier towards the CASZ and lighter far away. The oil biodegradation is the reason causing the high total acid number. The determination of effective reservoir depth ensures that all discovered fields up to now are high-production fields. The propagation and growth of boundary faults in the rift basins can be divided into a simple fault propagation pattern and a fault growth-linkage pattern. It is firstly found that the linkage of boundary fault segments controls the formation of petroleum systems. Three methods have been established to outline petroleum systems. And a new classification scheme of rift-type petroleum system has been put forward: pre-rift, syn-rift (including passive and active) and post-rift petroleum systems. This scheme will be very important for the further exploration of rift basins. This paper firstly established the formation models of oil pools for the passive rift basins in Sudan: the coupling of accommodation zones and main plays for the formation of giant fields. The overlapping of late rifting broke the anticlines to be several fault-blocks. This process determined that anti-fault blocks are the main traptypes in the cretaceous sequences and anticlines in the Paleogene. This can explain why the traptypes are different between the Muglad and Mefut basins, and will provide theoretic guidance for the exploration strategy. The established formation mechanism and models in this paper have had great potential guidance and promotion for the exploration in Sudan, and resulted in significant economic and social benefit. A giant field of 500 million tons oil in place was found 2003. The cost in Blocks 3/7 is only 0.25

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The grid is a foundation of reservoir description and reservoir simulation. The scale of grid size is vital influence for the precision of reservoir simulation the gridding of reservoir parameters require reasonable interpolation method with computing quickly and accurately. The improved distant weighted interpolation method has many properties, such as logical data points selection, exact interpolation, less calculation and simply programming, and its application can improve the precision of reservoir description and reservoir simulation. The Fractal geologic statistics describes scientifically the distribution law of various geological properties in reservoir. The Fractal interpolation method is applied in grid interpolation of reservoir parameters, and the result more accorded with the geological property and configuration of reservoir, and improved the rationality and quality of interpolation calculation. Incorporating the improved distant weighted interpolation method with Fractal interpolation method during mathematical model of grid-upscaling and grid-downscaling, the softwares of GROUGH(grid-upscaling) and GFINE (grid-downscaling) were developed aiming at the questions of grid-upscaling and grid-downscaling in reservoir description and reservoir simulation. The softwares of GROUGH and GFINE initial applied in the research of fined and large-scale reservoir simulation. It obtained fined distribution of remaining oil applying grid-upscaling and grid-downscaling technique in fined reservoir simulation of Es21-2 Shengtuo oilfield, and provided strongly and scientific basis for integral and comprehensive adjustment. It's a giant tertiary oil recovery pilot area in the alkaline/surfactant/polymer flooding pilot area of west district of Gudao oilfield, and first realized fined reservoir simulation of chemical flooding using grid-upscaling and grid-downscaling technique. It has wide applied foreground and significant research value aiming at the technique of grid-upscaling and grid-downscaling in reservoir description and reservoir simulation.

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Shepherd, Alistair, and T. C. Salmon, Toward a European Army: A Military Power in the Making? (Boulder, CO: Lynne Rienner, 2003), pp.x+237 RAE2008

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Cook, Anthony; Mege, D.; Garel, E.; Lagabrielle, Y., (2003) 'Volcanic rifting at Martian grabens', Journal of Geophysical Research 108(E5) pp. 1-33 RAE2008

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The giant cholinergic interneurons of the striatum are tonically active neurons (TANs) that respond with characteristic pauses to novel events and to appetitive and aversive conditioned stimuli. Fluctuations in acetylcholine release by TANs modulate performance- and learning-related dynamics in the striatum. Whereas tonic activity emerges from intrinsic properties of these neurons, glutamatergic inputs from thalamic centromedian-parafascicular nuclei, and dopaminergic inputs from midbrain, are required for the generation of pause responses. No prior computational models encompass both intrinsic and synaptically-gated dynamics. We present a mathematical model that robustly accounts for behavior-related electrophysiological properties of TANs in terms of their intrinsic physiological properties and known afferents. In the model, balanced intrinsic hyperpolarizing and depolarizing currents engender tonic firing, and glutamatergic inputs from thalamus (and cortex) both directly excite and indirectly inhibit TANs. If the latter inhibition, presumably mediated by GABAergic interneurons, exceeds a threshold, its effect is amplified by a KIR current to generate a prolonged pause. In the model, the intrinsic mechanisms and external inputs are both modulated by learning-dependent dopamine (DA) signals and our simulations revealed that many learning-dependent behaviors of TANs are explicable without recourse to learning-dependent changes in synapses onto TANs. The "teaching signal" that modulates reinforcement learning at cortico-striatal synapses may be a sequence composed of an adaptively scaled DA burst, a brief ACh burst, and a scaled ACh pause. Such an interpretation is consistent with recent data on cholinergic control of LTD of cortical synapses onto striatal spiny projection neurons.

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Pregnancy-Specific Glycoproteins (PSG) are the most abundant fetally expressed proteins in the maternal bloodstream at term. This multigene family are immunoglobulin superfamily members and are predominantly expressed in the syncytiotrophoblast of human placenta and in giant cells and spongiotrophoblast of rodent placenta. PSGs are encoded by seventeen genes in the mouse and ten genes in the human. Little is known about the function of this gene family, although they have been implicated in immune modulation and angiogenesis through the induction of cytokines such as IL-10 and TGFβ1 in monocytes, and more recently, have been shown to inhibit the platelet-fibrinogen interaction. I provide new information concerning the evolution of the murine Psg genomic locus structure and organisation, through the discovery of a recent gene inversion event of Psg22 within the major murine Psg cluster. In addition to this, I have performed an examination of the expression patterns of individual Psg genes in placental and non-placental tissues. This study centres on Psg22, which is the most abundant murine Psg transcript detected in the first half of pregnancy. A novel alternative splice variant transcript of Psg22 lacking the protein N1-domain was discovered, and similar to the full length isoform induces TGFβ1 in macrophage and monocytic cell lines. The identification of a bidirectional antisense long non-coding RNA transcript directly adjacent to Psg22 and its associated active local chromatin conformation, suggests an interesting epigenetic gene-specific regulatory mechanism that may be responsible for the high level of Psg22 expression relative to the other Psg family members upon trophoblast giant cell differentiation

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Today, the only surviving wild population of giant tortoises in the Indian Ocean occurs on the island of Aldabra. However, giant tortoises once inhabited islands throughout the western Indian Ocean. Madagascar, Africa, and India have all been suggested as possible sources of colonization for these islands. To address the origin of Indian Ocean tortoises (Dipsochelys, formerly Geochelone gigantea), we sequenced the 12S, 16S, and cyt b genes of the mitochondrial DNA. Our phylogenetic analysis shows Dipsochelys to be embedded within the Malagasy lineage, providing evidence that Indian Ocean giant tortoises are derived from a common Malagasy ancestor. This result points to Madagascar as the source of colonization for western Indian Ocean islands by giant tortoises. Tortoises are known to survive long oceanic voyages by floating with ocean currents, and thus, currents flowing northward towards the Aldabra archipelago from the east coast of Madagascar would have provided means for the colonization of western Indian Ocean islands. Additionally, we found an accelerated rate of sequence evolution in the two Malagasy Pyxis species examined. This finding supports previous theories that shorter generation time and smaller body size are related to an increase in mitochondrial DNA substitution rate in vertebrates.