38 resultados para Mural painting and decoration, Ancient.
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The Vespertilionidae is the largest family in the order Chiroptera and has a worldwide distribution in the temperate and tropical regions. In order to further clarify the karyotype relationships at the lower taxonomic level in Vespertilionidae, genome-wid
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Rhinolophus (Rhinolophidae) is the second most speciose genus in Chiroptera and has extensively diversified diploid chromosome numbers (from 2n=28 to 62). In spite of many attempts to explore the karyotypic evolution of this genus, most studies have been
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We have used a combination of chromosome sorting, degenerate oligonucleotide-primed polymerase chain reaction (DOP-PCR), chromosome painting and digital image capturing and processing techniques for comparative chromosome analysis of members of the genus Muntiacus. Chromosome-specific ''paints'' from a female Indian muntjac were hybridised to the metaphase chromosomes of the Gongshan, Black, and Chinese muntjac by both single and three colour chromosome painting. Karyotypes and idiograms for the Indian, Gongshan, Black and Chinese muntjac were constructed, based on enhanced 4', 6-diamidino-2-phenylindole (DAPI) banding patterns. The hybridisation signal for each paint was assigned to specific bands or chromosomes for all of the above muntjac species. The interspecific chromosomal homology was demonstrated by the use of both enhanced DAPI banding and comparative chromosome painting. These results provide direct molecular cytogenetic evidence for the tandem fusion theory of the chromosome evolution of muntjac species.
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With complete sets of chromosome-specific painting probes derived from flow-sorted chromosomes of human and grey squirrel (Sciurus carolinensis), the whole genome homologies between human and representatives of tree squirrels (Sciurus carolinensis, Callosciurus erythraeus), flying squirrels (Petaurista albiventer) and chipmunks (Tamias sibiricus) have been defined by cross-species chromosome painting. The results show that, unlike the highly rearranged karyotypes of mouse and rat, the karyotypes of squirrels are highly conserved. Two methods have been used to reconstruct the genome phylogeny of squirrels with the laboratory rabbit (Oryctolagus cuniculus) as the out-group: ( 1) phylogenetic analysis by parsimony using chromosomal characters identified by comparative cytogenetic approaches; ( 2) mapping the genome rearrangements onto recently published sequence-based molecular trees. Our chromosome painting results, in combination with molecular data, show that flying squirrels are phylogenetically close to New World tree squirrels. Chromosome painting and G-banding comparisons place chipmunks ( Tamias sibiricus), with a derived karyotype, outside the clade comprising tree and flying squirrels. The superorder Glires (order Rodentia + order Lagomorpha) is firmly supported by two conserved syntenic associations between human chromosomes 1 and 10p homologues, and between 9 and 11 homologues.
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To investigate the karyotypic relationships between Chinese muntjac (Muntiacus reevesi), forest musk deer (Moschus berezovskii) and gayal (Bos frontalis), a complete set of Chinese muntjac chromosome-specific painting probes has been assigned to G-banded chromosomes of these three species. Sixteen autosomal probes (i.e. 6-10, 12-22) of the Chinese muntjac each delineated one pair of conserved segments in the forest musk deer and gayal, respectively. The remaining six autosomal probes (1-5, and 11) each delineated two to five pairs of conserved segments. In total, the 22 autosomal painting probes of Chinese muntjac delineated 33 and 34 conserved chromosomal segments in the genomes of forest musk deer and gayal, respectively. The combined analysis of comparative chromosome painting and G-band comparison reveals that most interspecific homologous segments show a high degree of conservation in G-banding patterns. Eleven chromosome fissions and five chromosome fusions differentiate the karyotypes of Chinese muntjac and forest musk deer; twelve chromosome fissions and six fusions are required to convert the Chinese muntjac karyotype to that of gayal; one chromosome fission and one fusion separate the forest musk deer and gayal. The musk deer has retained a highly conserved karyotype that closely resembles the proposed ancestral pecoran karyotype but shares none of the rearrangements characteristic for the Cervidae and Bovidae. Our results substantiate that chromosomes 1-5 and 11 of Chinese muntjac originated through exclusive centromere-to-telomere fusions of ancestral acrocentric chromosomes. Copyright (C) 2005 S. Karger AG, Basel.
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We have made a set of chromosome-specific painting probes for the American mink by degenerate oligonucleotide primed-PCR (DOP-PCR) amplification of flow-sorted chromosomes. The painting probes were used to delimit homologous chromosomal segments among human, red fox, dog, cat and eight species of the family Mustelidae, including the European mink, steppe and forest polecats, least weasel, mountain weasel, Japanese sable, striped polecat, and badger. Based on the results of chromosome painting and G-banding, comparative maps between these species have been established. The integrated map demonstrates a high level of karyotype conservation among mustelid species. Comparative analysis of the conserved chromosomal segments among mustelids and outgroup species revealed 18 putative ancestral autosomal segments that probably represent the ancestral chromosomes, or chromosome arms, in the karyotype of the most recent ancestor of the family Mustelidae. The proposed 2n = 38 ancestral Mustelidae karyotype appears to have been retained in some modern mustelids, e.g., Martes, Lutra, ktonyx, and Vormela. The derivation of the mustelid karyotypes from the putative ancestral state resulted from centric fusions, fissions, the addition of heterochromatic arms, and occasional pericentric inversions. Our results confirm many of the evolutionary conclusions suggested by other data and strengthen the topology of the carnivore phylogenetic tree through the inclusion of genome-wide chromosome rearrangements. Copyright (C) 2002 S. KargerAG, Basel.
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Although the monophyly of Chiroptera is well supported by many independent studies, higher-level systematics, e.g. the monophyly of microbats, remains disputed by morphological and molecular studies. Chromosomal rearrangements, as one type of rare genomic changes, have become increasingly popular in phylogenetic studies as alternatives to molecular and other morphological characters. Here, the representatives of families Megadermatidae and Emballonuridae are studied by comparative chromosome painting for the first time. The results have been integrated into published comparative maps, providing an opportunity to assess genome-wide chromosomal homologies between the representatives of eight bat families. Our results further substantiate the wide occurrence of Robertsonian translocations in bats, with the possible involvement of whole-arm reciprocal translocations (WARTs). In order to search for valid cytogenetic signature(s) for each family and superfamily, evolutionary chromosomal rearrangements identified by chromosomal painting and/or banding comparison are subjected to two independent analyses: (1) a cladistic analysis using parsimony and (2) the mapping of these chromosomal changes onto the molecularly defined phylogenetic tree available fromthe literature. Both analyses clearly indicate the prevalence of homoplasic events that reduce the reliability of chromosomal characters for resolving interfamily relationships in bats.
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比较细胞遗传学研究发现物种的形成过程往往伴随着核型结构的变化,各种鹿属动物染色体的巨大差异正是很好的例证'赤魔的染色体被证明是由具有端着丝粒的祖先染色体经过多次的串联融合进化而来的。根据祖先染色体的形态和连接方式,可以将染色体串联融合主要分为三类:着丝粒一着丝粒融合,着丝粒一端粒融合和端粒一端粒融合。经典细胞遗传学,比较染色体涂色,卫星DNA序列和部分融合位点序列比较研究都支持串联融合假说。但串联融合的类型和分子机制迄今没有完全弄清楚。本论文旨在对魔属动物的串联融合类型和分子机制进行研究,分为两个部分:一、通过比较染色体涂色的方法,建立小鹿一林察一大额牛的比较染色体图谱,结合以前发表的结果来阐明鹿科(小魔)与牛科(大额牛),寮科(林磨)之间的核型关系;二、建立赤鹿的全基因组BAc文库,通过克隆定位的方法确立在赤魔的染色体进化过程中所发生的串联融合类型,并对其机制进行探讨。主要结果如下:利用小鹿的染色体特异探针与林寮,大额牛的染色体进行杂交,首次建立了小鹿一大额牛,小魔一林察的核型对比关系。结果显示小鹿的1-5、11号染色体均与林集和大额牛的多段染色体同源。结合高分辨的G带比较,发现小魔1-5和11号染色体上的与林爵和大额牛对应的所有同源片断在小鹿染色体上呈着丝粒一端粒连接排列。从而进一步证明小鹿的1-5和11号染色体是由2n=70的祖先核型通过染色体的着丝粒一端粒串联融合方式进化而来的。建立了我国第一个赤魔全基因组BAC文库,该文库由124800个克隆组成。大部分插入片段的大小在100-145kb之间,片段的平均大小为12<0kb。克隆定位显示克隆的分布与小鹿染色体大小成正比关系,说明整个文库没有染色体的偏倚,文库为整个基因组的6倍,覆盖率几乎为100%。通过赤鹿BAC克隆在小魔和赤鹿染色体上的精确定位,使我们得以准确判断小鹿染色体在赤鹿染色体同源片段上的连接方式,并确定串联融合的类型。结果进一步支持赤鹿的核型是由一个2n=70祖先核型通过着丝粒一端粒的融合方式进化而来的。
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Atomic force microscopy (AFM) and lateral force microscopy (LFM) were used simultaneously to analyze a model membrane bilayer structure consisting of a phospholipid outer monolayer deposited onto organosilane-derivatized mica surfaces, which were constructed by using painting and self-assembly methods. The phospholipid used as outer monolayer was dimyristoylphosphatidylcholine (DMPC). The hydrocarbon-covered substrate that formed the inner half bilayer was composed of a self-assembly monolayer (SAM) of octadecyltrichloroorganosilane (OTS) on mica. SAMs of DMPC were formed by exposing hydrophobic mica to a solution of DMPC in decane/isobutanol and subsequently immersing into pure water. AFM images of samples immersed in solution for varying exposure times showed that before forming a complete monolayer the molecules aggregated into dense islands (2.2-2.6 nm high) on the surface. The islands had a compact and rounded morphology. LFM, coupled with topographic data obtained with the atomic force mode, had made possible the distinction between DMPC and OTS. The rate constant of DMPC growth was calculated. This is the first systematic study of the SAM formation of DMPC by AFM and LFM imaging. It reveals more direct information about the film morphology than previous studies with conventional surface analytical techniques such as infrared spectroscopy, X-ray, or fluorescence microscopy.
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The unique geologic, geomorphic and climatic conditions of southeast Tibet have made the region to develop the multi-style and frequently occurring geologic hazards, especially the collapses and landslides and debris flows along the section of Ranwu-Lulang in Sichuan-Tibet highway. However, most of those geologic hazards have close relationship with the loose accumulations. That is, the loose accumulations are the main carrier of most geologic hazards. Thereof, the huge-thick accumulations along the highway is regarded as the objective in the thesis to study the geologic background, hazarding model and mitigation methods comprehensively, based on the multi-disciplinary theories and former materials. First of all, in the paper, based on field engineering geologic investigations, the genetic type and the characteristics of spatiotemporal distribution of the huge-thick loose accumulations along the highway, have been analysized from the factors of regional geology and geomorphy and climate, as well as the coupling acting of those factors with inoculation and eruption of the loose accumulations geologic hazards. The huge-thick loose accumulations has complex genetic types and specific regulations of spatiotemporal distribution, closely controlled by the outer environment of the region. The accumulations are composed of earth and boulder, with disorder structure and poor sorting, specific forming environments and depositing conditions. And its physical and mechanic properties are greatly distinguished from rock and common earth inland. When Sichuan-Tibet highway was firstly constructed along the north bank of Purlung Tsangpo River, the huge-thick loose accumulations was cut into many high and steep slopes. Through the survey to the cut-slopes and systematic investigation to their failures, the combination of height and angle of the accumulations slope has been obtained. At the same time, the types of genetic structure of those cut-slopes are also analysized and concluded, as well as their failure models. It is studied in the paper that there are piaster, duality, multielement and complexity types in genetic structure, and rip-dump-repose, rip-shear-slip and weathering-flake types in failure models. Moreover, it is briefly introduced present engineering performance methods and techniques dealing with the deformation and failure of the accumulations cut-slope. It is also suggested that several new techniques of slope enforcement and the method of landslide and rockfall avoiding should be applied. The research of high and steep cut-slope along the highway has broadened the acknowledgement of the combination of cut-slope height and angle. Especially, the dissertation also has made the monographic studies about the geologic background and hazarding models and prevention methods of some classic but difficult accumulations geologic hazards. They are: (1) Research of the engineering geologic background of the 102 landslide group and key problems about the project of tunnel. The 102 landslide group is a famous accumulational one composed of glacial tills and glaciofuvial deposit. The tunnel project is a feasible and optional one which can solve the present plight of “sliding after just harnessing” in the 102 section. Based on the glacial geomorphy and its depositing character, distribution of seepage line, a few drillhole materials and some surveying data, the position of contact surface between gneiss and accumulations has been recognized, and the retreating velocities of three different time scales (short, medium and long term) have been approximately calculated, and the weathering thickness of gneiss has also been estimated in the paper. On the basis of above acknowledgement, new engineering geomechnic mode is established. Numerical analysis about the stability of the No.2 landslide is done by way of FLAC program, which supplies the conclusion that the landslide there develops periodically. Thereof, 4 projects of tunnel going through the landslide have been put forwards. Safety distance of the tunnel from clinohefron has been numerically analysized. (2) Research of the geologic setting and disaster model and hazard mitigation of sliding-sand-slope. From the geologic setting of talus cone, it is indicated that the sliding-sand-slope is the process of the re-transportation and re-deposit of sand under the gravity action and from the talus cone. It is the failure of the talus cone essentially. The layering structure of the sliding-sand-slope is discovered. The models of movement and failure of the sliding-sand-slope has been put forwards. The technique, “abamurus+grass-bush fence+degradable culture pan”, is suggested to enforcement and green the sliding-sand-slope. (3) Characteristics and hazarding model and disaster mitigation of debris flow. The sources of solid material of three oversize debris flows have been analysized. It is found that a large amount of moraine existing in the glacial valley and large landslide dam-break are the two important features for oversize debris flow to be taken place. The disaster models of oversize and common debris flows have been generalized respectively. The former model better interpret the event of the Yigong super-large landslide-dam breaking. The features of common debris flow along the highway section, scouring and silting and burying and impacting, are formulated carefully. It is suggested that check dam is a better engineering structure to prevent valley from steeply scouring by debris flow. Moreover, the function of check dam in enforcing the slope is numerically calculated by FLAC program. (4) Songzong ancient ice-dammed lake and its slope stability. The lacustrine profile in Songzong landslide, more than 88 meters thick, is carefully described and measured. The Optical Simulated Luminescence (OSL) ages in the bottom and top of the silty clay layer are 22.5±3.3 kaB.P., 16.1±1.7 kaB.P., respectively. It is indicated by the ages that the lacustrine deposits formed during the Last Glacial Maximum ranging from 25ka B.P. to 15ka B.P. The special characteristics of the lacustrine sediment and the ancient lake line in Songzong basin indicated that the lacustrine sediment is related to the blocking of the Purlung Tsangpo River by the glacier in Last Glacial Maximum from Dongqu valley. The characteristics of the lacustrine profile also indicate that the Songzong ice-dammed lake might run through the Last Glacial Maximum. Two dimensional numerical modeling and analysis are done to simulate the slope stability under the conditions of nature and earthquake by FLAC program. The factor of safety of the lacusrtine slope is 1.04, but it will take place horizontal flow under earthquake activity due to the liquefaction of the 18.33 m silt layer. The realign to prevent the road from landslide is suggested.
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Study and Application of Damage Mechanism and Protection Method of reservoir in Nanpu Shallow Beach Sea Area is one of the key research projects of Jidong Oilfield Company of PetroChina Company Limited from 2007 to 2008. Located at Nanpu Sag in Huanghua Depression of Bohaiwan Basin, Nanpu Shallow Beach Sea Area with 1000km2 exploration area posseses three sets, shallow Minghuazhen Formation and Guantao Formation of Upper Tertiary, middle-deep Dongying Formation of Lower Tertiary, deep Ordovician, of oil bearing series, according to the achievement of the connecting 3D seismic structure interpretation and the structural geological comprehensive research. Its main reservoir types include Upper Tertiary structural reservoir, Lower Tertiary structural and lithological-structural reservoir, and Ordovician ancient buried hill reservoir. How to protect reservoir, complete well and lift high efficiently is the key to realize high and stable yield of the oil wells during drilling, completing well, testing and repairing well. It is important for reservoir protecting during drilling that directly relate to efficient exploration. Therefore, beginning with basic characteristics and sensitive analysis of reservoir, study of reservoir damage machinism and analysis of reservoir damage potential factor are emphasized when prediction analysis about three-pressure profiles is carried out. The study both of physical and chemical properties and of the strata of the technology of borehole stabilization and reservoir protecting are outstanding. As the conclusions follow: (1)Based on the laboratory experiment about basalt cores, prediction of three- pressure profiles about 30 wells on No.1 and No.2 structure is practiced. The laws of plane pressure distribution are analyzed. (2)According to the analyses about reservoir feature data and about sensitivity evaluation to damage factor in Nanpu oil field, the scheme of reservoir protecting to the sand reservoir of Guantao Formation and the first section of Dongying Formation is put forward. (3)On basis of the analyses on lithological characteristics, mineral compositions, clay minerals, electrical behavior features, physical and chemical properties of basalt of Guantao formation in No.1 and No.2 structure, instability mechanism of basalt sidewall and technical countermeasures are obtained. (4)Aiming at the characteristics of Ordovician dissolution-pore fracture type carbonate reservoir, the scheme of the reservoir protecting to Ordovician is put forward. Creative study of the film forming and sealing and low invasion reservoir protection drilling fluid are successful. In summary, through the study of reservoir heterogeneity and sensitivity, a set of technology and schemes of reservoir protecting is put forward, which is adaptive during drilling the target bed in the research area and establishes the base for efficient exploration. Significant effect has showed in its application in Nanpu oil field.
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The formation of civilization, one of great marks in the history of human's society development, has been remained one of the hottest topics in the world. Many theories have been put ford to explain its causes and mechanisms. Although more attentions have been paid to its development, the role of environmental change should not be ignored. In this paper, the level of ancient farming productivity was analyzed, the mechanisms and the process of Chinese ancient civilization formation was explored, and some causes why Chinese ancient civilization shows many different features from other 5 ancient civilizations of the world was analyzed. The main results and conclusions are presented as followed. 1. Compared with the productivity level of other five ancient civilizations, the productivity of ancient China characterized by a feature of extensive not intensive cultivation was lower than that of other five ancient civilizations whose agriculture were based on irrigation. 2. The 5 5000 a B.P. cold event may have facilitated the formation of Egypt and Mesopotamian ancient civilizations and also have had an influence on the development of Neolithic culture in China. 3. The 4 000 a B.P. cold event, which may be the coldest period since the Younger Dryas cold event and signifies the changes from the early Holocene Climate Optimum to late Holocene in many regions of the world, resulted in the great migration of the Indo-European peoples from north Europe to other part of the World and the collapses of ancient civilizations in Egypt, Indus and the Mesopotamian and the collapse of five Neolithic cultures around central China. More important than that is the emergence of Chinese civilization during the same period. Many theories have been put ford to explain why it was in Zhongyuan area not other places whose Neolithic cultures seem more advanced that gave rise to civilization. For now no theory could explain it satisfiedly. Archaeological evidence clearly demonstrate that war was prevailed the whole China especially during the late Longshan culture period, so it seemed war has played a very important role in the emergence of China ancient civilization. Carneiro sees two conditions as essential to the formation of complex societies in concert with warfare, i.e. population growth and environmental circumscription. It was generally through that China couldn't evolved into the environmental circumscription and population pressure because China has extensive areas to live, but that depends on situations. The environmental circumscription area was formed due to the 4000a B.P. cold event and companied flooding disasters, while the population pressure is formed due to three factors; 1) population grow rapidly because of the suitable environment provided by the Holocene Optimum and thus laid its foundations for the ancient human population; 2) population pressure is also related to the primitive agricultural level characterized by extensive not intensive cultivation; 3) population pressure was mainly related to the great migrations of people to the same areas; 4) population pressure was also related to productivity decrease due to the 4 000a B.P. cold event. 4. When population pressure is formed, war is the most possible way to solve the intensions between population and the limited cultivated land and then resulted in the formation of civilization. In this way the climate change during the 4 000a B.P. cold event may have facilitated the emergence of Chinese ancient civilization. Their detailed relations could also be further understood in this way: The first birth places of China ancient civilization could be in Changjiang areas or (and) Daihai area, Shandong province rather than in central China and the emergence time of ancient civilization formed in central China should be delayed if the 4 000a B.P. cold event and companied flooding disasters didn't occurred.
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Air exploratory discussion of an ancient Chinese algorithm, the Ying Buzu Shu, in about 2nd century BC, known as the rule of double false position in the West is given. In addition to pointing out that the rule of double false position is actually a translation version of the ancient Chinese algorithm, a comparison with well-known Newton iteration method is also made. If derivative is introduced, the ancient Chinese algorithm reduces to the Newton method. A modification of the ancient Chinese algorithm is also proposed, and some of applications to nonlinear oscillators are illustrated.
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Die swell is an important, phenomenon. in polymer processing, and is explained usually by rheological properties of the fluid. Because of the nonuniform of temperature distribution on the free surface of the liquid jet, the thermo capillary convection driven by surface tension gradient exists. The rheological fluid flowing out of a die and painting on a moving solid wall is studied by the numerical finite element method of a two-dimensional and unsteady model in the present paper, and both the rheological effect of a non-Newtonian fluid and the thermocapillary effect are considered. The results show that both,effects; will enlarge the cross-section of the fluid jet, and the rheological effect of non-Newtonian fluid dominates the process in general.