The flowering plant Arabidopsis thaliana is an important model system for identifying genes and determining their functions. Here we report the analysis of the genomic sequence of Arabidopsis. The sequenced regions cover 115.4 megabases of the 125-megabase genome and extend into centromeric regions. The evolution of Arabidopsis involved a whole-genome duplication, followed by subsequent gene loss and extensive local gene duplications, giving rise to a dynamic genome enriched by lateral gene transfer from a cyanobacterial-like ancestor of the plastid. The genome contains 25,498 genes encoding proteins from 11,000 families, similar to the functional diversity of Drosophila and Caenorhabditis elegans--the other sequenced multicellular eukaryotes. Arabidopsis has many families of new proteins but also lacks several common protein families, indicating that the sets of common proteins have undergone differential expansion and contraction in the three multicellular eukaryotes. This is the first complete genome sequence of a plant and provides the foundations for more comprehensive comparison of conserved processes in all eukaryotes, identifying a wide range of plant-specific gene functions and establishing rapid systematic ways to identify genes for crop improvement.

/pdf/analysis-of-the-genome-sequence-of-the-flowering-plant-3vizsb52m2.pdf

Analysis of the genome sequence of the flowering plant Arabidopsis thaliana.

ion of those listed by the students? In general, we found that the event name itself combined most readily with superordinate noun categories; thus, one gets dressed with clothes and needs various kitchen utensils to make breakfast. When such activities were analyzed into their script elements, the basic level appeared as the level of abstraction of objects necessary to script the events; e.g., in getting dressed, one puts on pants, sweater, and shoes, and in making breakfast, one cooks eggs in a frying pan. With respect to prototypes, it appears to be those category members judged the more prototypical that have attributes that enable them to fit into the typical and agreed upon script elements. We are presently collecting normative data on the intersection of common events, the objects associated with those events and the other sets of events associated with those objects.2 In addition, object names for eliciting events are varied in level of abstraction and in known prototypicality in given categories. Initial results show a similar pattern to that obtained in the earlier research in which it was found that the more typical members of superordinate categories could replace the superordinate in sentence frames generated by subjects told to "make up a sentence" that used the superordinate (Rosch, 1977). That is, the task of using a given concrete noun in a sentence appears to be an indirect method of eliciting a statement about the events in which objects play a part; that indirect method showed clearly that prototypical category members are those that can play the role in events expected of members of that category. The use of deviant forms of object names in narratives accounts for several recently explored effects in the psychological literature. Substituting object names at other than the basic level within scripts results in obviously deviant descriptions. Substitution of superordinates produces just those types of narrative that Bransford and Johnson (1973) have claimed are not comprehended; for example, " The procedure is actually quite simple. First you arrange things into different groups. Of course, one pile may be sufficient [p. 400]." It should be noted in the present context that what Bransford and Johnson call context cues are actually names of basic-level events (e.g., washing clothes) and that one function of hearing the event name is to enable the reader to translate the superordinate terms into basic-level objects and actions. Such a translation appears to be a necessary aspect of our ability to match linguistic descriptions to world knowledge in a way that produces the "click of comprehension." On the other hand, substitution of subordinate terms for basic-level object names in scripts gives the effect of satire or snobbery. For example, a review ( Garis, 1975) of a pretentious novel accused of actually being about nothing more than brand-name snobbery concludes, "And so, after putting away my 10

Cognition and Categorization

Simple repetitive DNA sequences are a widespread and abundant feature of genomic DNA. The following several features characterize such sequences: (1) they typically consist of a variety of repeated motifs of 1-10 bases--but may include much larger repeats as well; (2) larger repeat units often include shorter ones within them; (3) long polypyrimidine and poly-CA tracts are often found; and (4) tandem arrangements of closely related motifs are often found. We propose that slipped-strand mispairing events, in concert with unequal crossing-over, can readily account for all of these features. The frequent occurrence of long tandem repeats of particular motifs (polypyrimidine and poly-CA tracts) appears to result from nonrandom patterns of nucleotide substitution. We argue that the intrahelical process of slipped-strand mispairing is much more likely to be the major factor in the initial expansion of short repeated motifs and that, after initial expansion, simple tandem repeats may be predisposed to further expansion by unequal crossing-over or other interhelical events because of their propensity to mispair. Evidence is presented that single-base repeats (the shortest possible motifs) are represented by longer runs in mammalian introns than would be expected on a random basis, supporting the idea that SSM may be a ubiquitous force in the evolution of the eukaryotic genome. Simple repetitive sequences may therefore represent a natural ground state of DNA unselected for coding functions.

Slipped-strand mispairing: a major mechanism for DNA sequence evolution.

Edited by the people who were forerunners in creating the field, together with contributions from 34 leading international experts, this handbook provides the definitive reference on Blind Source Separation, giving a broad and comprehensive description of all the core principles and methods, numerical algorithms and major applications in the fields of telecommunications, biomedical engineering and audio, acoustic and speech processing. Going beyond a machine learning perspective, the book reflects recent results in signal processing and numerical analysis, and includes topics such as optimization criteria, mathematical tools, the design of numerical algorithms, convolutive mixtures, and time frequency approaches. This Handbook is an ideal reference for university researchers, RD algebraic identification of under-determined mixtures, time-frequency methods, Bayesian approaches, blind identification under non negativity approaches, semi-blind methods for communicationsShows the applications of the methods to key application areas such as telecommunications, biomedical engineering, speech, acoustic, audio and music processing, while also giving a general method for developing applications

https://ie.technion.ac.il/~mcib/Gribonval_Zibulevsky_SCA_chapter.pdf

Handbook of Blind Source Separation: Independent Component Analysis and Applications

We report the sequence and analysis of the 814-megabase genome of the sea urchin Strongylocentrotus purpuratus, a model for developmental and systems biology. The sequencing strategy combined whole-genome shotgun and bacterial artificial chromosome (BAC) sequences. This use of BAC clones, aided by a pooling strategy, overcame difficulties associated with high heterozygosity of the genome. The genome encodes about 23,300 genes, including many previously thought to be vertebrate innovations or known only outside the deuterostomes. This echinoderm genome provides an evolutionary outgroup for the chordates and yields insights into the evolution of deuterostomes.

/pdf/the-genome-of-the-sea-urchin-strongylocentrotus-purpuratus-1ef2nuqc4h.pdf

良明城所

Papers

The Salk Institute for Biological Studies(話題)

良明 城所

Papers

The Salk Institute for Biological Studies(話題)

良明城所