1,723,717 research outputs found
Gas2 a growth arrest specific protein is a component of microfilament network system
No full textIn this report we analyze the protein product of a growth arrest-specific gene, gas2, by means of an affinity-purified antibody raised against the protein produced in bacteria. The regulation of Gas2 biosynthesis reflects the pattern of mRNA expression (Schneider, C., R. King, and L. Philipson. 1988. Cell. 54:787-793): its relative level is tightly associated with growth arrest. Gas2 seems to be regulated also at the posttranslational level via a phosphorylation mechanism. Gas2 is well conserved during the evolution with the same apparent molecular mass (36 kD) between mouse and human.
We also demonstrate that Gas2 is a component of the microfilament system. It colocalizes with actin fiber, at the cell border and also along the stress fiber, in growth-arrested NIH 3T3 cells. The pattern of distribution, detected in arrested cells, can also be observed in growing cells when they are microinjected with the purified GST-Gas2 protein.
In none of the analyzed oncogene-transformed NIH 3T3 cell lines was Gas2 expression induced under serum starvation
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Quaternary ammonium salt catalyzed azidolysis of epoxides with trimethylsilyl azide
No full textA range of tetrabutylammonium salts very efficiently catalyzes the azidolysis of epoxides with trimethylsilyl azide in a solvent-free process in good yields
The silyloxy-Cope rearrangement of syn-aldol products: Evolution of a powerful synthetic strategy
No full textEnantiomerically pure 1.5-hexadienes incoporated into a silylated aldol structure undergo rapid, clean, high-yielding and highly stereoselective Cope rearrangements. The 7-oxo-2-enimides thus obtained are formally the products of a gamma -1,4-selective addition of a metal dienolate to an a,P-unsaturated aldehyde-a transformation which current methodology can not accomplish directly and stereoselectively. They have proved to he very useful synthetic intermediates en route to highly substituted oxygen and nitrogen heterocycles, functionalized cyclohexanes, and 1,3.5,...-polyol chains
The silyloxy-Cope rearrangement of syn-aldol products: Evolution of a powerful synthetic strategy
No full textEnantiomerically pure 1.5-hexadienes incoporated into a silylated aldol structure undergo rapid, clean, high-yielding and highly stereoselective Cope rearrangements. The 7-oxo-2-enimides thus obtained are formally the products of a gamma -1,4-selective addition of a metal dienolate to an a,P-unsaturated aldehyde-a transformation which current methodology can not accomplish directly and stereoselectively. They have proved to he very useful synthetic intermediates en route to highly substituted oxygen and nitrogen heterocycles, functionalized cyclohexanes, and 1,3.5,...-polyol chains
Catalytic, enantioselective syntheses of beta-lactones-versatile synthetic building blocks in organic chemistry
No full text
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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