断陷盆地构造枢纽部位油气富集规律

以十屋断陷为例,根据其构造演化、主要断层特征及油气成藏条件分析,揭示多旋回断陷盆地构造枢纽带与油气富集关系.结果表明:十屋断陷枢纽部位经历了断陷期、断拗过渡期、拗陷期、萎缩隆升期等复杂的构造演化,多期差异构造变形及断裂活动导致了小宽枢纽带南段和北段具有相似性及差异性,后期构造反转发育部位多为早期断层发育部位,且主要集中在主干断层上,构造运动产生位移被断裂和褶皱吸收;不同阶段的隆起部位相叠加,使枢纽部位与构造高点相对位置发生变化,枢纽部位相对位置由原来的古隆起演变为斜坡部位;枢纽部位早期为油气的有利指向区,晚期具有良好的保存条件,同时发育多类型圈闭、有利沉积相组合及生储盖组合,围绕枢纽带可形成复式油气聚集带.     

Genome of the marsupial Monodelphis domestica reveals innovation in non-coding sequences

We report a high-quality draft of the genome sequence of the grey, short-tailed opossum (Monodelphis domestica). As the first metatherian ('marsupial') species to be sequenced, the opossum provides a unique perspective on the organization and evolution of mammalian genomes. Distinctive features of the opossum chromosomes provide support for recent theories about genome evolution and function, including a strong influence of biased gene conversion on nucleotide sequence composition, and a relationship between chromosomal characteristics and X chromosome inactivation. Comparison of opossum and eutherian genomes also reveals a sharp difference in evolutionary innovation between protein-coding and non-coding functional elements. True innovation in protein-coding genes seems to be relatively rare, with lineage-specific differences being largely due to diversification and rapid turnover in gene families involved in environmental interactions. In contrast, about 20% of eutherian conserved non-coding elements (CNEs) are recent inventions that postdate the divergence of Eutheria and Metatheria. A substantial proportion of these eutherian-specific CNEs arose from sequence inserted by transposable elements, pointing to transposons as a major creative force in the evolution of mammalian gene regulation.     

Evolutionary relationship and species separation of four morphologically similar stichotrichous ciliates （Protozoa, Ciliophora）

Phylogenetic and taxonomic studies on ciliate protists using molecular approaches have been demonstrated to be very reliable to form strong conclusions and results. In the present work, species separation of some morphologically similar stichotrichous ciliates, two species of Pseudokeronopsis and two species of Apokeronopsis, was reexamined using amplified ribosomal DNA restriction analysis (PCRRFLP). Five of 10 restriction enzymes revealed species-specific polymorphic patterns, of which four similar stichotrichs could be significantly separated and identified. Among them, EcoR I offered almost no significantly different restriction fragment patterns, but the four species could be separated from one another and identified with Hae III. Distinctly different restriction digestion haplotypes and similarity indices separated the species, and were used to construct a phylogeny. Phylogenies based on ITS2 nucleotide sequences and ITS2 secondary structures supported the separation of Pseudokeronopsis and Apokeronopsis using RFLP analysis, although three Pseudokeronopsis carnea populations did not cluster together. In addition, phylogenetic analyses using multiple algorithms confirmed that these two genera formed two distinct groups within the urostylids.     

A high-resolution map of human evolutionary constraint using 29 mammals

The comparison of related genomes has emerged as a powerful lens for genome interpretation. Here we report the sequencing and comparative analysis of 29 eutherian genomes. We confirm that at least 5.5% of the human genome has undergone purifying selection, and locate constrained elements covering ～4.2% of the genome. We use evolutionary signatures and comparisons with experimental data sets to suggest candidate functions for ～60% of constrained bases. These elements reveal a small number of new coding exons, candidate stop codon readthrough events and over 10,000 regions of overlapping synonymous constraint within protein-coding exons. We find 220 candidate RNA structural families, and nearly a million elements overlapping potential promoter, enhancer and insulator regions. We report specific amino acid residues that have undergone positive selection, 280,000 non-coding elements exapted from mobile elements and more than 1,000 primate- and human-accelerated elements. Overlap with disease-associated variants indicates that our findings will be relevant for studies of human biology, health and disease.     

浅谈高校图书馆服务模式创新和形象塑造

网络化、信息化、数字化时代的到来改变了图书馆的运行环境,使高校图书馆的信息服务出现了危机,因此需要创新服务模式,优化服务流程,即开展个性化服务,设立学科信息服务中心,开展层次化信息服务。     

Mining the draft human genome

Now that the draft human genome sequence is available, everyone wants to be able to use it. However, we have perhaps become complacent about our ability to turn new genomes into lists of genes. The higher volume of data associated with a larger genome is accompanied by a much greater increase in complexity. We need to appreciate both the scale of the challenge of vertebrate genome analysis and the limitations of current gene prediction methods and understanding.     

Genome sequence, comparative analysis and haplotype structure of the domestic dog

Here we report a high-quality draft genome sequence of the domestic dog (Canis familiaris), together with a dense map of single nucleotide polymorphisms (SNPs) across breeds. The dog is of particular interest because it provides important evolutionary information and because existing breeds show great phenotypic diversity for morphological, physiological and behavioural traits. We use sequence comparison with the primate and rodent lineages to shed light on the structure and evolution of genomes and genes. Notably, the majority of the most highly conserved non-coding sequences in mammalian genomes are clustered near a small subset of genes with important roles in development. Analysis of SNPs reveals long-range haplotypes across the entire dog genome, and defines the nature of genetic diversity within and across breeds. The current SNP map now makes it possible for genome-wide association studies to identify genes responsible for diseases and traits, with important consequences for human and companion animal health.     

Phylogenetic investigation on five genera of tintinnid ciliates （Ciliophora, Choreotrichia）, based on the small subunit ribosomal RNA gene sequences

The phylogenetic relationship among tintinnid ciliates are relatively poorly studied based on molecular data. In the present work, seven species belonging to five genera of the order Tintinnida (Amphorellopsis acuta, Codonellopsis nipponica, Favella taraikaensis, Stenosemella nivalis, Tintinnopsis beroidea, Tintinnopsis cylindrica and Tintinnopsis lohmanni) were analyzed using the information on their small subunit ribosomal RNA gene sequences. Phylogenetic trees were constructed using Bayesian inference (BI), maximum parsimony (MP), neighbor-joining (NJ), and least-squares (LS) methods. Generally, similar topologies were revealed with high or moderate supports, in which the main results show that (1) all tintinnids analyzed belong to a single assemblage; (2) congeners in Tintinnopsis do not cluster together, which indicates that the lorica-based definition for this genus is not consistent with the SSU rRNA phylogeny; (3) A. acuta groups with Tintinnidium mucicola but not with Eutintinnus, indicating that the traditional family Tintinnidae might be a paraphyletic group; (4) Stenosemella and Codonellopsis are clearly most related and possibly even merged into one genus regarding their similar morphology and molecular analyses, and possession of a hyaline collar is the only characteristic of the genus.