新疆拜城黑孜尔水库垂直形变观测与现今断层活动特征

根据跨断层定点水准、基线观测资料和垂直形变的水准高程观测数据分析,黑孜尔断裂 Ｆ２定点水准的垂直位移量为 ０． １４ ｍｍ／ａ,基线缩短量为 ０． ４８ ｍｍ／ａ,断层滑动角■≈３７°,现今垂直形变速率为 ０． ６９３ ｍｍ／ａ。结合地震活动和区域地质构造研究,认为黑孜尔断裂近期水平活动强度大于垂直运动强度,该区在未来１～３年内仍可能发生６级以上地震。     

秭归龙会观5.1级震区及其邻区新生代以来的地壳应力场特征

为了研究三峡坝库区的地壳稳定性,根据奥陶－侏罗纪地层中构造变形的实际观测资料,计算了秭归龙会观５．１级震区及其邻区新生代以来区域应力场的主应力方向。结果表明：主压应力为北东东向,主张应力为北北西向;现代构造应力场与新生代以来应力场基本一致;晚第三纪以来,该区构造应力场相对稳定和统一。     

城市建成环境对居民体力活动的影响 ——以福州市的经验研究为例

利用福州中心城区的社会调查、POI、道路网、用地性质等数据,在社区尺度探究城市建成环境对居民休闲型中高强度体力活动的影响。研究发现：① 低密度土地利用与体力活动时长呈正向关联,功能单一和邻近主干道则对体力活动起到抑制作用。② 体力活动目的地对不同人群具有差异化影响,体育用地和付费运动场所仅能促进中高阶层和中高收入者的体力活动,而周边公共运动设施的丰富程度更具普适性意义。③ 通过纳入运动偏好和单独分析保障房、单位大院及房改房住户达到规避居住自选择的目的,证明上述建成环境特征对体力活动的影响是独立且稳健的。     

Isolation, distribution and evaluation of cytotoxic and antioxidant activity of cultivable actinobacteria from the Oman Sea sediments

Screening bioactive natural products from bacteria is a determinative step in the drug discovery programs. The present study aim to isolate actinobacteria from the Oman Sea sediments for determining the effects of different culture media and treatments on the yield of the isolation process, and measure the DPPH radical scavenging and Artemia cytotoxic activity of culture extracts of the actinobacterial isolates. A total of 290 actinobacterial isolates were collected from 14 sediment samples. Heat treatment(40.68%) and M_4 medium(29.31%) exhibited the maximum isolation rates of actinobacteria. Streptomyces isolates were dominantly distributed in all of the investigated stations according to 16 S rRNA gene sequencing. The distribution pattern of Streptomyces followed a depth-dependent frequency trend, whereas the members of rare genera including Micromonospora, Nocardia Actinoplanes, Nocardiopsis, Saccharopolyspora and Crossiella were distributed in deeper stations. Approximately,25% of the examined isolates could scavenge 90% of 10~(–4) mol/L DPPH solutions at 1 250 μg/mL final concentration of their ethyl acetate culture extracts. Furthermore, the most potent extracts could scavenge DPPH radicals with IC50 ranges from 356.8 to 566.4 μg/mL. Brine shrimp cytotoxicity tests showed that 38.88% of the examined culture extracts exhibited LC_(50) lower than 1 000 μg/mL against the Artemia cells. Moreover, the most potent culture extracts exhibited LC_(50) range from 335.4 to 534.4 μg/mL. Phylogenetic analysis by 16 S rRNA gene sequence revealed that the OS 005, OS 263 and OS 157 closely related to Streptomyces djakartensis, Streptomyces olivaceus and Nocardiopsis dassonvillei respectively. These results suggested the widespread distribution of the antioxidant and cytotoxic producing actinobacteria in the Oman Sea sediments, which could be considered as promising candidates for the discovery of microbial bioactive compounds.     

大亚湾西部海域沉积物中生物硅的含量及其分布特征

采用2. 0 mol/dm~3Na_2CO_3溶液5h单点化学提取-硅钼蓝连续分光光度分析法分别测定了大亚湾西部海域13个表层沉积物和1个沉积物岩芯中生物硅的含量.表层沉积物和沉积物岩芯中生物硅含量占比分别为0. 69%～2. 02%和1. 24%～2. 05%,平均值分别为1. 42%和1. 60%.结果证实西大亚湾沉积物中生物硅含量水平与我国南海近岸海域基本一致.在210Pbex测年的基础上,通过分析沉积物岩芯中生物硅、有机物、无机碳等多指标,揭示近百年来大亚湾周边环境变化对海洋环境的影响,证实了上世纪80年代以来西大亚湾周边农业、海水养殖业和工业发展等人类活动加剧了该海域生态环境变化,尤其90年代核电站运行对海洋生态变化造成一定的影响.     

A high-precision heuristic model to detect home and work locations from smart card data

Smart card-automated fare collection systems now routinely record large volumes of data comprising the origins and destinations of travelers. Processing and analyzing these data open new opportunities in urban modeling and travel behavior research. This study seeks to develop an accurate framework for the study of urban mobility from smart card data by developing a heuristic primary location model to identify the home and work locations. The model uses journey counts as an indicator of usage regularity, visit-frequency to identify activity locations for regular commuters, and stay-time for the classification of work and home locations and activities. London is taken as a case study, and the model results were validated against survey data from the London Travel Demand Survey and volunteer survey. Results demonstrate that the proposed model is able to detect meaningful home and work places with high precision. This study offers a new and cost-effective approach to travel behavior and demand research.     

Scaling-laws of Radio Spike Bursts and Their Constraints on New Solar Radio Telescopestwo

Radio observation is one of important methods in solar physics and space science. Sometimes, it is almost the sole approach to observe the physical processes such as the acceleration, emission, and propagation of non-thermal energetic particles, etc. So far, more than 100 solar radio telescopes have been built in the world, including solar radiometers, dynamic spectrometers, and radioheliographs. Some of them have been closed after the fulfillment of their primary scientific objectives, or for their malfunctions, and thus replaced by other advanced instruments. At the same time, based on some new technologies and scientific ideas, various kinds of new and much more complicated solar radio telescopes are being constructed by solar radio astronomers and space scientists, such as the American E-OVSA and the solar radio observing system under the framework of Chinese Meridian Project II, etc. When we plan to develop a new solar radio telescope, it is crucial to design the most suitable technical parameters, e.g., the observing frequency range and bandwidth, temporal resolution, frequency resolution, spatial resolution, polarization degree, and dynamic range. Then, how do we select a rational set of these parameters? The long-term observation and study revealed that a large strong solar radio burst is frequently composed of a series of small bursts with different time scales. Among them, the radio spike burst is the smallest one with the shortest lifetime, the narrowest bandwidth, and the smallest source region. Solar radio spikes are considered to be related to a single magnetic energy release process, and can be regarded as an elementary burst in solar flares. It is a basic requirement for the new solar radio telescope to observe and discriminate these solar radio spike bursts, even though the temporal and spatial scales of radio spike bursts actually vary with the observing frequency. This paper presents the scaling laws of the lifetime and bandwidth of solar radio spike bursts with respect to the observing frequency, which provide some constraints for the new solar radio telescopes, and help us to select the rational telescope parameters. Besides, we propose a spectrum-image combination mode as the best observation mode for the next-generation solar radio telescopes with high temporal, spectral, and spatial resolutions, which may have an important significance for revealing the physical essence of the various non-thermal processes in violent solar eruptions.     

预测华北地区年度地震趋势的支持向量机分类方法

以太阳黑子数、地球自转速率变化数据和全球7级以上地震应变释放量作为预测因子,使用支持向量机分类方法建模预测中国华北地区年度地震强度,预测准确率为0.93,表明该方法具有较好的预测效果.     

Zoning and layering in diorites of the scottish caledonian appinite suite

Dioritic plugs (< 1 km across) are common associates of the late Caledonian, post-tectonic granites of the Scottish Highlands. These contain a very wide range of rock types from ultramafic through mesocratic diorites to anorthositic and granitic. These rocks form steeply dipping, wall-parallel layers and zones within the plugs. Outer layers are shown to form first, inner layers later. Mafic zones are composed of the minerals seen as phenocrysts in chilled margins and have the chemical characteristics of cumulates. The inner margins of the mafic zones reflect the onset of plagioclase crystallization. Core zones also show inward variations in mineralogy and texture which define vertical, wall-parallel cylinders. These variations are ascribed to fractional crystallization accompanying accretion of rock onto the pipe walls. Cores in different intrusions may be mafic, mesocratic, or leucocratic, which indicates vertical zonation in the bodies. The mafic cores additionally show that recharge with less evolved magma occurred in some cases. The few larger (> 1 km diameter) intrusions show examples of layering and lamination dipping at low to moderate angles. These indicate the beginning of a change from wall-dominated to floor-dominated crystallization as intrusion diameter increases. A comparison is made with the nature and origin of layering in other intrusions.     

造山带大陆斜坡沉积类型

造山带大陆斜坡可以划分出有扇与无扇大陆斜坡两种沉积类型。有扇大陆斜坡以近源浊积岩、碎屑流为特色;无扇大陆斜坡以远源浊积岩、等深岩、半远洋沉积为特色。因而大陆斜坡也是一个多种沉积作用活跃的场所。造山带深水沉积绝不是常人认为是单一的复理石、千篇一律的重力流,而是内容十分丰富的沉积作用非常活跃和堆积的场所。