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101.
The Miocene Kitami rhyolite, consisting of orthopyroxene and plagioclase-phyric lavas and dikes, occurs on the back-arc side of the Kuril arc with coeval basalts and Fe-rich andesites. Temperatures estimated from orthopyroxene–ilmenite pairs exceed 900°C. Although the whole rock compositions of the Kitami rhyolite correspond to S-type granites (i.e., high K, Al, large ion lithophile elements, and low Ca and Sr), Sr–Nd isotope compositions are remarkably primitive, and similar to those of the coeval basalts and andesites. They are distinct from those of lower crustal metamorphic rocks exposed in the area. Comparison of chondrite-normalized rare earth element (REE) patterns between the rhyolite and the basalts and andesites show that the rhyolite is more light REE enriched, but has similar heavy REE contents than the basalts. All rhyolites show negative Eu anomalies. The geochemical data suggest that did not formed by simple dehydration melting of basaltic rocks or fractional crystallization of basaltic magmas. The features of slab-derived fluids expected from recent high pressure experimental studies indicates that mantle wedge is partly metasomatized with “rhyolitic” materials from subducted slabs; it is more likely that very low degree partial melting of the metasomatized mantle wedge formed the rhyolite magma.  相似文献   
102.
目的:观察加味大黄?虫丸对原发性胆汁性胆管炎(PBC)肝星状细胞损伤状态下转化生长因子-β1(TGF-β1)、Smads的影响。方法:将20只大鼠随机分为干预组与对照组,每组各10只。干预组灌胃加味大黄?虫丸混悬液1.5 ml/100 g,对照组灌胃等量0.9%氯化钠注射液,每天1次,持续1周。将肝星状细胞T6(HSC-T6)细胞分为6组,分别为空白组、对照组、5%空白血清组、10%空白血清组、5%含药血清组、10%含药血清组,培养24 h。建立乳酸损伤模型,造模成功后分为5组:空白组、对照组、正常组、模型组、中药组。测定细胞活性,细胞中TGF-β1、Smad3、Smad7 mRNA表达,TGF-β1、磷酸化Smad3、磷酸化Smad7 mRNA蛋白表达。结果:各组HSC-T6细胞活性对照组、5%空白血清组、10%空白血清组、5%含药血清组、10%含药血清组与空白组比较,差异均有统计学意义(P<0.01)。TGF-β1、Smad3、Smad7 mRNA表达及TGF-β1、p-Smad3、p-Smad7 mRNA蛋白表达水平,模型组与空白组比较,中药组与模型组比较,差异均有统计学意义(P<0.01或P<0.05)。结论:加味大黄土?丸治疗PBC的作用机制与降低TGF-β1、Smad3水平,提高Smad7水平相关。  相似文献   
103.
目的:基于数据挖掘分析《卫生宝鉴》中治疗脾胃病方剂的用药规律。方法:运用中医传承辅助平台(TCMISS)V2.5,采用频次统计、关联规则和聚类分析等数据挖掘方法,对《卫生宝鉴》中所载脾胃病的用药规律进行分析。结果:共收集处方151首,中药168味。频次≥17次的中药有21味,排前5位的依次是陈皮、白术、炙甘草、木香、干姜;温性中药使用频次最高,其次是寒性、平性中药;辛味药出现最多,其次是苦味、甘味药;排前5位的中药归经依次是脾、胃、肺、大肠、心经;频次≥14次的中药组合24个,对药物组合进行关联规则分析得到中药组合17个;聚类分析得到新方聚类的中药组合5组,对应新方组合5组。结论:通过中医传承辅助平台分析得出,《卫生宝鉴》中所载治疗脾胃病的处方注重甘辛温补、健脾消滞,慎用苦寒药,该研究结果可为临床治疗脾胃病开发新药物提供一定的参考  相似文献   
104.
The first CO2 exposure experiments on several species of pelagic copepods inhabiting surface and deep layers in the western North Pacific were conducted. Living organisms were collected from two layers between the surface and 1,500 m between latitudes of 11 and 44°N, and they were exposed aboard ship to various pCO2 up to about 98,000 μatm. Mortality of copepods from both shallow and deep layers in subarctic to subtropical regions increased with increasing pCO2 and exposure time. Deep-living copepods showed higher tolerance to pCO2 than shallow-living copepods. Furthermore, deep-living copepods from subarctic and transitional regions had higher tolerances than the subtropical copepods. The higher tolerances of the deep-living copepods from subarctic and transitional regions may be due to the adaptation to the natural pCO2 conditions in the subarctic ocean.  相似文献   
105.
Sample preparation protocols for flow cytometry (FCM) analysis with five algal viruses were optimized: Heterocapsa circularisquama virus (HcV), Heterosigma akashiwo virus (HaV), Chaetoceros salsugineum nuclear inclusion virus (CsNIV), Rhizosolenia setigera RNA virus (RsRNAV) and H. circularisquama RNA virus (HcRNAV). The optimum staining protocols differed significantly among the viruses tested. FCM counts for the large DNA algal viruses HaV and HcV (∼0.2 μm in diameter) were similar to numbers determined by epifluorescence microscopy (EFM). In contrast, FCM counts of viruses smaller than 40 nm that harbor DNA (CsNIV) or RNA genomes (RsRNAV, HcRNAV) were comparable to or lower than most probable number (MPN) values, which indicate only infectious virus number, suggesting that the FCM counts were underestimates. This is presumably because their single particle fluorescence signals were below the detection limit for the flow cytometer. These results indicate that a large portion of the smaller viruses in the aquatic plankton virus community may be overlooked by FCM.  相似文献   
106.
As part of the research program WEST-COSMIC Phase I (1997–2001), vertical profiles down to the greater depths (0–2000 m or 5800 m) of the plankton community structure composed of heterotrophic bacteria, phytoplankton, protozooplankton and metazooplankton were studied at one station in each subarctic (44°N) and in transitional region (39°N), and two stations in subtropical region (30°N and 25°N); all in 137–155°E in the western North Pacific Ocean. The biomass of all four taxonomic groups decreased rapidly with increasing depths at all stations, although the magnitude of depth-related decrease differed among the groups. As plankton community structure, metazooplankton biomass and bacterial biomass occupied >50% of the total in 0–2000 and 2000–4000 or 5000 m strata, respectively, at subarctic and transitional stations, while bacterial biomass contributed to >50% of the total consistently from 0 through 4800 or 5800 m at subtropical stations. Metazooplankton biomass integrated over the greater depths exhibited a clear latitudinal pattern (high north and low south), but this was not the case for those of the other taxonomic groups. As a component of metazooplankton, an appreciable contribution of diapausing copepods to the metazooplankton was noted at subarctic and transitional stations, but they were few or nil at subtropical stations. As protozooplankton assemblages, heterotrophic microflagellates (HMF) and dinoflagellates were two major components at subarctic and transitional stations, but were only HMF predominated at subtropical stations. From biomass ratios between heterotrophic bacteria, HMF and dinoflagellates, “sinking POC-DOC-heterotrophic bacteria-HMF-heterotrophic dinoflagellates” link was proposed as a microbial food chain operative in the deep layer of the western North Pacific. All results are discussed in the light of latitudinal differences in the structure and functioning of plankton community contributing to the ‘biological pump’ in the western North Pacific Ocean. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
107.
The distribution of phototrophic bacteria was investigated during the summers of 1969 and 1970 in Omura Bay of western Kyushu. Phototrophic sulfur- and nonsulfur-bacteria were distributed numerously in the mud and bottom water. Brown strains usually dominated in number. In water column, other than bottom water, there were usually few or no phototrophic bacteria. On occasion, however, a large number of brown bacteria were found in the middle of water column. Six strains, two each of the purple, green and brown bacterial colonies, were isolated from mud and sea water. The purple and green bacterial strains were identified as belonging to the generaChromatium andChlorobium, respectively. The brown strains could not be identified using Bergey's manual, but were found to be similar to the brownChlorobium described byPfennig. All six strains required sulfide for growth. Heterotrophic tendency was greater for the purple and green strains than for the brown strains. Their growth was enhanced by the addition of thymine. Living cells, taken from enrichment cultures of mud samples from four stations, gave absorption spectra almost identical to the spectrum of brownChlorobium. Thus it appears that during the summer brownChlorobium is the dominant phototrophic bacterial group in Omura Bay.  相似文献   
108.
This paper describes the characteristics of currents around Hokkaido using a current vector map compiled by chasing the displacement of sea marks on a pair of successive thermal infrared images taken from a satellite, NOAA-6. The points of some sea surface patterns showing distinctive features which can be commonly identified in both images are called Sea Marks≓. This sea mark chase method≓ has a great advantage over velocity measurements by boats or buoys, in that it gives a synoptic view of the velocity distribution over a broad sea area extending for some hundreds of miles on a short time scale of half a day.In order to investigate the current in the late fall of 1981, we used the data taken at 19:05 JST on 30 October and at 7:20 JST on 31 October. With these data taken with a 12 hr difference, the measurement accuracy of the speed of sea marks reached ±0.1 knot through geometrical correction. The velocity vectors of sea marks agreed with results of GEK measurements performed on those days, and also with the mean current pattern obtained in the past based on sea surface data.The most distinct features recognized were some cyclonic and anticyclonic eddies of the order of 100 km in diameter which dominated in the Kuril Basin of the Okhotsk Sea. They appeared clearly in the original NOAA images and their physical parameters were determined quantitatively from the vector map. These eddies were located in the region of decay of the Soya Warm Current and were rotating at a speed nearly as large as that of the current. The problems of what feeds energy to these eddies and how long they live remain to be solved in future studies.  相似文献   
109.
Twin formation in hematite during dehydration was investigated using X-ray diffraction, electron diffraction, and high-resolution transmission electron microscopy (TEM). When synthetic goethite was heated at different temperatures between 100 and 800 °C, a phase transformation occurred at temperatures above 250 °C. The electron diffraction patterns showed that the single-crystalline goethite with a growth direction of [001]G was transformed into hematite with a growth direction of [100]H. Two non-equivalent structures emerged in hematite after dehydration, with twin boundaries at the interface between the two variants. As the temperature was increased, crystal growth occurred. At 800 °C, the majority of the twin boundaries disappeared; however, some hematite particles remained in the twinned variant. The electron diffraction patterns and high-resolution TEM observations indicated that the twin boundaries consisted of crystallographically equivalent prismatic (100) (010), and (1\(\bar{1}\)0) planes. According to the total energy calculations based on spin-polarized density functional theory, the twin boundary of prismatic (100) screw had small interfacial energy (0.24 J/m2). Owing to this low interfacial energy, the prismatic (100) screw interface remained after higher-temperature treatment at 800 °C.  相似文献   
110.
A new synchrotron X-ray diffraction study of chromium oxide Cr2O3 (eskolaite) with the corundum-type structure has been carried out in a Kawai-type multi-anvil apparatus to pressure of 15 GPa and temperatures of 1873 K. Fitting the Birch–Murnaghan equation of state (EoS) with the present data up to 15 GPa yielded: bulk modulus (K 0,T0), 206 ± 4 GPa; its pressure derivative K0,T , 4.4 ± 0.8; (?K 0,T /?T) = ?0.037 ± 0.006 GPa K?1; a = 2.98 ± 0.14 × 10?5 K?1 and b = 0.47 ± 0.28 × 10?8 K?2, where α 0,T  = a + bT is the volumetric thermal expansion coefficient. The thermal expansion of Cr2O3 was additionally measured at the high-temperature powder diffraction experiment at ambient pressure and α 0,T0 was determined to be 2.95 × 10?5 K?1. The results indicate that coefficient of the thermal expansion calculated from the EoS appeared to be high-precision because it is consistent with the data obtained at 1 atm. However, our results contradict α 0 value suggested by Rigby et al. (Brit Ceram Trans J 45:137–148, 1946) widely used in many physical and geological databases. Fitting the Mie–Grüneisen–Debye EoS with the present ambient and high-pressure data yielded the following parameters: K 0,T0 = 205 ± 3 GPa, K0,T  = 4.0, Grüneisen parameter (γ 0) = 1.42 ± 0.80, q = 1.82 ± 0.56. The thermoelastic parameters indicate that Cr2O3 undergoes near isotropic compression at room and high temperatures up to 15 GPa. Cr2O3 is shown to be stable in this pressure range and adopts the corundum-type structure. Using obtained thermoelastic parameters, we calculated the reaction boundary of knorringite formation from enstatite and eskolaite. The Clapeyron slope (with \({\text{d}}P/{\text{d}}T = - 0.014\) GPa/K) was found to be consistent with experimental data.  相似文献   
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