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The Luobusa Ophiolite, Southern Tibet, lies in the eastern portion of Indus-Yarlung Zangbo suture zone that separates Eurasia from the Indian continent. An aeromagnetic reconnaissance survey has revealed an EW-trending Yarlung Zangbo River aeromagnetic anomaly zone, and it is considered to be caused mainly by the Indus-Yarlung Zangbo Ophiolite. The Luobusa Ophiolite reflects the eastern portion of the Yarlung Zangbo River aeromagnetic anomaly zone. Conventionally, the ultramafic rock in the Luobusa Ophiolite is considered as the origin of the high magnetic anomalies. However, results from the surface magnetic survey and the magnetic susceptibility measurements from drill cores indicate that the high magnetic anomalies are distributed inhomogeneously in the Luobusa Ophiolite. In some cases, the susceptibility exhibits more than 30 times difference between two sides of the same sample. A fact emerged that the susceptibility of dunite with serpentinization is higher than that of fresh dunite, harzburgite and chromite when we analyzed the measurement results. In order to understand the origin of the high magnetic anomalies, we measured the density and susceptibility of 17 samples, microscopic and electron probe analyses have been performed as well. The result indicates the presence of dunite with serpentinization containing an abundant of micro-fissures filled with magnetite. Olivine has a susceptibility of about 2.7-351 (×10 SI), pyroxene about 16-320, and chromite about 200-800. All these units feature relatively low susceptibility in ultramafic rock, and only the magnetite is characterized by a high susceptibility of about 200,000 (×10 SI). Based on these observations, we conclude that the precipitation of magnetite in the process of serpentinization of the olivine caused by the geological process in the Luobusa Ophiolite is the origin of high magnetic anomalies. [ABSTRACT FROM AUTHOR]

The origin of the new A (H1N1) influenza virus recently emerging in North America is a hot controversial topic of significance in disease control and risk assessment. Some experts claimed that it was an unusually mongrelized mix of human, avian and swine influenza viruses, while some others concluded that it was totally a simple re-assortment hybrid of two lineages of swine influenza viruses. Here the phylogenetic diversity of the viral PB1, PA and PB2 gene sequences using online web servers, and the results suggest that all the 8 genetic segments of the new virus were possibly from two lineages of swine influenza viruses, and one of the lineage was a mongrelized mix of human, avian and swine influenza viruses emerging in the world approximately 10 years ago. Considering the recent epidemiological trends of the new virus, we believe it will spread more widely in the world and persist long in human populations. It also could spread among swine populations. The future wide spreading of the new virus may coincide the disappearance of a subtype of previous human influenza A virus. [ABSTRACT FROM AUTHOR]

Hetianhe gas field, Lungudong gas field and Tazhong gas field are marine marine-origin natural gas reservoirs in the craton area in the Tarim Basin. The natural gas is generated from Cambrian source rocks. The simulation experiment indicated that the cracking of the dispersedly dissoluble organic matter remaining in the source rocks is the main origin of marine natural gas. There are two modes to form gas reservoirs, one is the dry gas reservoir such as Hetianhe gas field, in which gas accumulated on the fault belt with violent tectonic movement, the other is condensate gas reservoir formed on the inheriting uplift such as Lunnan and Tazhong gas fields. The hybrid simulation experiment of cracking gas and crude oil indicated that crude oil accumulated on a large scale in those uplift belts at the early stage, and natural gas filled the ancient oil reservoir at the late stage, and the gas reservoirs were formed after the gas mixed with the crude oil. [ABSTRACT FROM AUTHOR]

Marattioid ferns are an ancient lineage of primitive vascular plants that first appeared in the middle Carboniferous. Extant members are almost exclusively restricted to tropical regions, and the species-rich family Angiopteridaceae are limited in their distribution to the eastern hemisphere; relationships within the group are currently vague. Here the phylogenetic relationship between Angiopteris Hoffm. and Archangiopteris Christ et Gies. was evaluated based on the sequence analysis of chloroplast rbcL gene and trnL-F intergenic spacer with MEGA2 and MrBayes v3.0b4. On the basis of the phylogenetic pattern and fossil record, we further estimated the divergence time for the two genera. The phylogenetic trees revealed that all species of Angiopteris and Archangiopteris in this study formed a monophyletic group with strong statistical support, but the relationship between the two genera remained unresolved based on individual sequence analysis. On the other hand, the sequence analyses of combined data set revealed that Archangiopteris species diverged first, indicating that Archangioptens may not be a direct derivative as traditionally assumed. The clade of Angiopteris and Archangiopteris appears to have diversified in the late Oligocene (≈26 Ma) based on the molecular estimate. Thus, the evolutionary history of extant Angiopteris and Archangioptenis has been characterized by ancient origin and recent diversification, and these groups are not relic and endangered lineages as traditionally considered. [ABSTRACT FROM AUTHOR]

Gelman and Bloom found that adults and children's object naming was sensitive to how an object was created (man-made or not), but they did not reveal on which specific level of conceptual system this effect was. Using a free-naming task and a force-choice task, two experiments were conducted to test a hypothesis that this effect was specifically on domain level ("artifact/non-artifact" distinction). In Experiment 1, participants were asked to name shortly-depicted objects, rate their confidence, and report their reasons for each naming response. Results showed that most of the naming responses in "man-made" condition were in artifact domain, and most in "natural" condition were in non-artifact do- main, although in both conditions names were very divergent on basic level. In Experiment 2, another group of participants were asked to choose one from two names (one in artifact domain and the other in non-artifact domain) to match the same shortly-depicted objects presented in the first experiment. Results of Experiment 1 on domain level were replicated in Experiment 2. These convergent findings supported the hypothesis that the effect of object's origin is specifically on domain level of conceptual system of objects. Reasons explicitly reported for naming responses in Experiment 1 suggested that participants might automatically infer objects' functions in "man-made" condition but not in "natural" condition. Here the function-based hypothesis of artifacts classification is discussed. [ABSTRACT FROM AUTHOR]

In No. 3 coalseam of Chengzhuang Coalmine of Jincheng City, there exists the visible fracture system consisting of joints, gas-expanding fractures and cleats. The gas-expanding fractures develop mainly in the bright coal sub-layer and cleats, in the vitrain and bright coal. The joints fall into two types, one developing in the coalseam and the other cutting through the whole coalseam and entering into the top and bottom rock layer. The development direction of joints is basically similar to that of gas-expanding fractures: NNE and NNW. The formation of the visible fracture system is classified as the stage of the development of cleat fissures in the coalification period, the stage of the full development of cleats and the formation of gas-expanding fractures in the second coalification period and the stage of the formation of joints by structural function. There is the spatial unhomogeneity in three dimensions for the visible fracture system of the coal seam in Chengzhuang Coalmine: the regular distribution of the visible fractures as groups in the plane and the coal sub-layer with high permeability rate in profile. The research findings of the visible fracture system of coal seam can be applied to the drilling of the coalbed methane and to heightening the let-off efficiency of coalseam gas. [ABSTRACT FROM AUTHOR]

Organisms have variable genome sizes and contain different numbers of genes. This difference demonstrates that new gene origination is a fundamental process in evolutionary biology. Though the study of the origination of new genes dated back more than half a century ago, it is not until the 1990s when the first young gene jingwei was found that empirical investigation of the molecular mechanisms of origination of new genes became possible. In the recent years, several young genes were identified and the studies on these genes have greatly enriched the knowledge of this field. Yet more details in a general picture of new genes origination are to be clarified. We have developed a systematic approach to searching for young genes at the genomic level, in the hope to summarize a general pattern of the origination and evolution of new genes, such as the rate of new gene appearance, impact of new genes on their host genomes, etc. [ABSTRACT FROM AUTHOR]

Chloroplast rbcL sequences of 60 species of Polystichum sensu lato (s.l.), including 23 new sequences from southwest China, were used to assess the phylogenetic relationships within the genus. On the basis of estimated evolution rate of rbcL gene and the genetic distance data that passed relative-rate tests, we further estimated the divergence times between some clades of the genus. The phylogenetic relationships were inferred using the neighbor-joining and maximum-parsimony methods, both methods producing trees with completely congruent topology. These trees reveal that all species of Polystichum s.l. in this study (including Cyrtomium and Cyrtomidictyum) form a monophyletic group. The basal split in Polystichum s.l. separates a clade with all Asian members from a clade containing other species from all over the world. The phylogenetic and divergence time estimation results lead us to suggest that Polystichum s.l. originated in Asia in the late Late Cretacous (≈76 Ma) and migrated into other places in the world in early Eocene (≈46 Ma). [ABSTRACT FROM AUTHOR]

XRD, TEM, SEM and EDS are employed to analyze smectites in the clay fraction of the surface sediments from the East Pacific. It is shown from the XRD results that the clay fraction consists of about 20% smectites. Three types of smectites are identified, Fe-rich (Type I), Fe, Mg-rich (Type II) and Na,Ca smectite (Type III), and most of them are not wellcrystallized. Type I is widely distributed in sediments, showing honeycomblike in the SEM, and aggregated or dispersive hairlike, or cloudy assemblage with a bit curl near its edge in the TEM. This type is considered to be typomorphic type of authigenic smectite in the East Pacific. Type II is similar to Type I in micromorphology in the TEM, showing a transition micronite, while Type III is tabletlike in the TEM with an unclear edge. Type I may be altered from volcanics and some of them even precipitated from the low subthermal water. Type II could also be formed in the ocean floor, while Type III comes from dry and distant continental area. This study suggests that the characteristic of chemical composition and morphology of smectite may give a clue to understand sediment source, origin of minerals and sedimentation in the deep sea. [ABSTRACT FROM AUTHOR]

To better understand the characteristics of the clay minerals in the southern Yellow Sea, the X-ray quantitative determinations have been carried out for the surface samples obtained from the Yellow Sea. With newly compiled clay mineral synoptic maps, the depositional processes were described for four main clay minerals (illite, chlorite, kaolinite and smectite). The analysis shows that most clay minerals are of terrigenous source with the Huanghe River acting as the major sediment supplier. Besides, the source of muddy sediments in the Yellow Sea was also discussed. As for the central Yellow Sea mud (CYSM), the sediments in its northern part mainly come from the Huanghe River, and those in the rest are of multi-origin. Very similarly, a large amount of sediments in the northern part of the southeastern Yellow Sea Mud (SEYSM) derive from the Keum River and Yeongsan River, while those in the southern part are of multi-origin. [ABSTRACT FROM AUTHOR]

Focuses on a study on the crystalline-fluid melt inclusions in aquamarines in pegmatites from Hunan and Yunnan Provinces in China. General geology of pegmatites; Characters of crystalline-fluid melt inclusions; Chemical composition of single inclusion in aquamarine determinated by laser Roman microprobe; Analysis of ore-forming solution and trace gas.

Examines the transport of gold by dihydrogen sulfide-rich oil field waters and the origin of the Carlin-type gold deposits in China and in the Great Basin in the United States. Types of dihydrogen sulfide-forming reactions; Reasons for the suitability of carbonate rocks for the accumulation of dihydrogen sulfide; Possible role of a mineralizing event during the Paleozoic time on the evolution of Carlin-type deposits.