The acraman impact structure: source of ejecta in late precambrian shales, South australia

A major probable impact structure occurs in middle Proterozoic dacitic volcanics in the Gawler Ranges, central South Australia. The structure has an inner depressed area about 30 kilometers in diameter that contains the Lake Acraman salina, an intermediate depression or ring about 90 kilometers in diameter, and a possible outer ring approximately 160 kilometers in diameter. Outcrops of dacite in Lake Acraman are intensely shattered and contain shatter cones and multiple sets of shock lamellac in quartz grains. The Acraman structure is the largest probable impact structure known in Australia and is the likely source of dacitic ejecta found in late Precambrian marine shales some 300 kilometers to the east.     

Iridium anomaly in the upper devonian of the canning basin, Western australia

A moderate iridium anomaly, about 20 times the local background, has been found in Upper Devonian rocks in the Canning Basin. It occurs at or near the Frasnian-Famennian boundary, which is known to be associated with a major massextinction event of global extent. The anomaly occurs in an extremely condensed limestone sequence laid down under quiet deepwater conditions. Its occurrence suggests a causal link with some form of meteoroid impact. Moreover, carbon isotope data indicate that a large reduction in biomass could have occurred at this level. However, the anomaly coincides with a stromatolite bed containing the fossil cyanobacterium Frutexites; iridium, platinum, iron, manganese, cobalt, arsenic, antimony, and cerium are preferentially concentrated in filaments of this organism, with concentrations ranging from two to five times that of the matrix. It is possible that Frutexites extracted these elements directly from seawater, without the need for their derivation from an extraterrestrial source.     

个性化教育:高校教学需要突破的新课题

个性化教育已经成为人们关注的热点。文章分析了我国传统教育在某种程度上阻碍学生个性化发展的原因;指出了高等学校应该培养勤于思考,具有理性精神、勇于进取,带有闯劲精神、善于学习,具有创新精神的大学生;提出了从转变观念、改进教学方法、创造宽松环境、尊重个性等方面来加强个性化教育,明确高等学校教育改革的方向。     

Sorted patterned ground: new appalachian localities South of the glacial border

Sorted stripes, nets, and polygons in the Appalachians of Pennsylvania, West Virginia, and Virginia display patterns and stone orientations visibly similar to those of ground patterned under current cold climates. Larger forms appear inactive or fossil and may provide data on the paleoclimate and slope stability.     

包含体表达基因工程牛生长激素提取、变复性及纯化的研究

为了取得较好的复性效果.对重组牛生长激素的纯化及变复性条件进行了研究.结果表明;发酵菌体高压匀浆破碎、离心得到的包含体在7.5 mol/L尿素中变性24 h后.以100 mmol/L Tris·HCI pH 10.0稀释至尿素浓度4.5 mol/L,4℃复性48 h,对20 mmol/L Tris·HCI pH 9.0透析除盐可以成功对重组牛生长激素复性;采用截留分子量100 kD、5 kD超滤膜对复性重组牛生长激素浓缩,FPLC纯化后可得到高纯度的目标蛋白.     

Kestel: an early bronze age source of tin ore in the taurus mountains, Turkey

An ancient mine located at Kestel on the outskirts of Nigde, in the Taurus Mountains of south central Turkey, has been dated by radiocarbon and pottery type to the third millennium B.C. Archeological soundings in the mine located cassiterite (tin oxide) in the detritus of ancient mining activity. Cassiterite is also present in veins and, as placer deposits, in streams nearby. Since tin is used with copper in order to form bronze but is thinly distributed in the earth's crust, the presence of tin ore at Kestel offers a source for the much sought after tin of the Bronze Age. The discovery of an ancient mine containing cassiterite sheds light on this question, but also greatly complicates the accepted picture of regional economic patterns in the highland resource areas of Anatolia and of interregional metal exchange in the formative periods of urbanization and metal use in the eastern Mediterranean.     

Rapid deformation of the South flank of kilauea volcano, hawaii

The south flank of Kilauea volcano has experienced two large [magnitude (M) 7.2 and M 6.1] earthquakes in the past two decades. Global Positioning System measurements conducted between 1990 and 1993 reveal seaward displacements of Kilauea's central south flank at rates of up to about 10 centimeters per year. In contrast, the northern side of the volcano and the distal ends of the south flank did not displace significantly. The observations can be explained by slip on a low-angle fault beneath the south flank combined with dilation deep within Kilauea's rift system, both at rates of at least 15 centimeters per year.     

引入新设备新技术深化《测量学》实践性教学

传统的测量实验实习受到现代测绘新设备、新技术的强烈冲击和影响.如何在测量学实践性教学中引入新设备、新技术,是教学中所面临的一个重要问题.     

Mid-Pleistocene Acheulean-like stone technology of the Bose basin, South China

Stone artifacts from the Bose basin, South China, are associated with tektites dated to 803,000 +/- 3000 years ago and represent the oldest known large cutting tools (LCTs) in East Asia. Bose toolmaking is compatible with Mode 2 (Acheulean) technologies in Africa in its targeted manufacture and biased spatial distribution of LCTs, large-scale flaking, and high flake scar counts. Acheulean-like tools in the mid-Pleistocene of South China imply that Mode 2 technical advances were manifested in East Asia contemporaneously with handaxe technology in Africa and western Eurasia. Bose lithic technology is associated with a tektite airfall and forest burning.     

Population Genetic Analysis of the Rice Stem Borer, Chilo suppressalis, in the South China

Genetic variation and patterns of genetic differentiation of the rice stem borer, Chilo suppressalis (Lepidoptera: Pyralidae), from the South China were analyzed using 6 microsatellite markers and two partial mtDNA (cox1 and cox2) regions. All of the 6 microsatellite loci were polymorphic in the studied seven populations. The allelic richness per population ranged between 5.67 and 14.00, and average H E and H O values were 0.6246-0.8329 and 0.2634-0.6061, respectively. As the mitochondrial genome is a single genetic locus, we only present results for the concatenated data set (cox1 plus cox2 gene sequences, 513 bp). The concatenated data showed high level of genetic diversity and there are 23 variable polymorphic sites among the 513 sites in concatenated data. Nearly all of (20 of 21) pairwise F ST comparisons among populations showed genetic differentiation with moderate to high pairwise F ST values based on microsatellite markers. However, for the mtDNA data, most of the seven populations did not show significant differentiation with other populations. The differences of population differentiation obtained with the two different genetic markers could be mainly attributed to the different mutation rates of microsatellite and mtDNA. There was not genetic structure existed in these studied populations based on microsatellite loci and mtDNA data. The analysis based on network, mismatch distribution, Tajima’s D and F S indicated that the studied populations were from the recent same ancestor or the same refuge and followed by a sudden demographic expansion condition.     

韩国新村运动突出国民精神培养对我国新农村建设的启示

韩国新村运动着力打造“勤勉、自助、协作”精神,这种突出国民精神培养的做法,成就了韩国的新村建设事业,也为我们今天正在从事的社会主义新农村建设提供了宝贵的实践先例,具有重要的参考意义。我国的新农村建设,除了党和国家的大政方针以外,最大的动力也在于发动农民、尊重农民的首创精神。因此,新农村建设应注重农民精神的培养,以农民为行动主体,并注意因势利导。     

南方羊布鲁氏杆菌病的危害·诊断及防治

近年来,南方许多省区大力发展养羊业,随着大批北方羊只被引进到南方地区,羊布鲁氏杆菌病也开始在南方地区发生.由于南方养羊生产者和管理者对布鲁氏杆菌病缺乏足够的认识,该病潜在的危害性会更大.介绍了布鲁氏杆菌病的病原、流行特点、危害与诊断,并针对南方地区提出防治策略,旨在为南方羊产业的发展提供参考依据.     

中日韩自由贸易协定发展分析

随着世界经济环境的不断变化 ,以及各国的经济发展 ,以WTO为代表的多边贸易也面临了困境。为弥补WTO基本原则框架协议的不足 ,地区性贸易协定渐渐扩散。但是中日韩 3国所处的东北亚地区还没签定任何贸易协定。笔者研究了中日韩自由贸易协定的可行性和战略选择。     

南药学学科产生背景·定位及外延探讨

介绍了海南大学南药学学科产生的背景、学科定位和该学科发展的外延,并探讨了该学科的发展目标。     

U-Pb isotopic age of the StW 573 hominid from Sterkfontein, South Africa

Sterkfontein cave, South Africa, has yielded an australopith skeleton, StW 573, whose completeness has excited great interest in paleoanthropology. StW 573, or "Little Foot," was found 25 meters below the surface in the Silberberg Grotto. 238U-206Pb measurements on speleothems immediately above and below the fossil remains, corrected for initial 234U disequilibrium, yield ages of 2.17 +/- 0.17 million years ago (Ma) and 2.24(-0.07)(+0.09) Ma, respectively, indicating an age for StW 573 of close to 2.2 Ma. This age is in contrast to an age of approximately 3.3 Ma suggested by magnetochronology and ages of approximately 4 Ma based on 10Be and 26Al, but it is compatible with a faunal age range of 4 to 2 Ma.     

Early tertiary age of pitchstone in the northern black hills, South dakota

A block of pitchstone in the northern Black Hills, South Dakota, is Paleocene in age, according to potassium-argon dating of biotite and fission-track dating of zircon in the sample. These data invalidate published suggestions that the age is much younger. The pitchstone is not extrusive in its present position but instead is in a volcanic pipe with other fragments that came downward from as much as 1100 meters above the modern surface.     

Differences Between the Concentrations in Rabbit Body Fluid of Berberine Hydrochloride, Chlorogenic Acid, Baicalin, and Their Minimal Inhibitory Concentrations

To explore the relationship between the heat-clearing and detoxicating functions and the bacteriostatic actions of berberine hydrochloride （Ber. H）, chlorogenic acid （Chlo. A）, and baicalin （Bai）, their concentrations in rabbit body fluid were compared with their minimal inhibitory concentrations （MICs）. Their concentrations in rabbit blood and tissue fluid were determined by reversed-phase high performance liquid chromatography, and their MICs to Escherichia coli were determined by tube dilution method. The results showed that the peak concentrations of Ber. H, Chlo. A, and Bai in rabbit blood were 3.2, 5.03, and 7.63 μg mL^-1, and in rabbit tissue fluid were 0.12, 0.11, and 0.12 μg mL^-1, respectively. Their MICs to E. coli were, respectively, 1.0×10^3, 3.75 × 10^3, and 6.75 ×10^3μg mL^-1, which were far higher than the concentrations in rabbit body fluids. This study indicates that Ber. H, Chlo. A, and Bai have weak bacteriostatic actions and do not reach their effective inhibitory concentrations in rabbit body fluids, and their heat-clearing and detoxicating functions are independent on the bacteriostatic actions.