980 resultados para Z


Relevância:

20.00% 20.00%

Publicador:

Resumo:

We study electroweak Sudakov effects in single W, Z and γ production at large transverse momentum using soft collinear effective theory. We present a factorized form of the cross section near the partonic threshold with both QCD and electroweak effects included and compute the electroweak corrections arising at different scales. We analyze their size relative to the QCD corrections as well as the impact of strong-electroweak mixing terms. Numerical results for the vector-boson cross sections at the Large Hadron Collider are presented.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Metallic catcher foils have been investigated on their thermal release capabilities for future superheavy element studies. These catcher materials shall serve as connection between production and chemical investigation of superheavy elements (SHE) at vacuum conditions. The diffusion constants and activation energies of diffusion have been extrapolated for various catcher materials using an atomic volume based model. Release rates can now be estimated for predefined experimental conditions using the determined diffusion values. The potential release behavior of the volatile SHE Cn (E112), E113, Fl (E114), E115, and Lv (E116) from polycrystalline, metallic foils of Ni, Y, Zr, Nb, Mo, Hf, Ta, and W is predicted. Example calculations showed that Zr is the best suited material in terms of on-line release efficiency and long-term operation stability. If higher temperatures up to 2773 K are applicable, tungsten is suggested to be the material of choice for such experiments.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In Escherichia coli, the Min system, consisting of three proteins, MinC, MinD, and MinE, negatively regulates FtsZ assembly at the cell poles, helping to ensure that the Z ring will assemble only at midcell. Of the three Min proteins, MinC is sufficient to inhibit Z-ring assembly. By binding to MinD, which is mostly localized at the membrane near the cell poles, MinC is sequestered away from the cell midpoint, increasing the probability of Z-ring assembly there. Previously, it has been shown that the two halves of MinC have two distinct functions. The N-terminal half is sufficient for inhibition of FtsZ assembly, whereas the C-terminal half of the protein is required for binding to MinD as well as to a component of the division septum. In this study, we discovered that overproduction of the C-terminal half of MinC (MinC(122-231)) could also inhibit cell division and that this inhibition was at the level of Z-ring disassembly and dependent on MinD. We also found that fusing green fluorescent protein to either the N-terminal end of MinC(122-231), the C terminus of full-length MinC, or the C terminus of MinC(122-231) perturbed MinC function, which may explain why cell division inhibition by MinC(122-231) was not detected previously. These results suggest that the C-terminal half of MinC has an additional function in the regulation of Z-ring assembly.

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Resumo:

As is well know, the long-lasting influence in Poland of Hoffmanowa’s conservative pedagogical treatise « Keepsake of a Good Mother » (1819) was criticized by more progressive Polish women writers of the 19th century, such as Narcyza Żmichowska and Eliza Orzeszkowa. But the unexpected success of that book in other Slav countries later in the 19th century, especially in Bohemia, is less well known. Honorata z Wiśniowskich Zapová (1825-1856), a member of the Galician Polish szlachta who moved to Prague after her marriage in 1841 to the Czech writer K. V. Zap, has been recently exhumed as a Czech writer by Czech and Polish literary criticism: apart from her essays in Czech journals on her native country, much emphasis has been laid on the value of her most important work, Nezabudky, dar našim pannám (Forget-me-not: A Gift to Our Young Ladies, published in 1859), which was the first book of pedagogy dedicated to the instruction of young women in Bohemia. In her preface to this book, Zapová mentions Hoffmanowa as being one of her many sources of inspiration. Wishing to know more about what exactly Zapová owes to Hoffmanowa, in this article I compare Hoffmanowa’s book of pedagogy with Zapová’s. I am astonished to discover that Zapová’s book is in fact an almost literal translation from Polish to Czech of „Keepsake of a Good Mother” – in other words, that it is a plagiarism of Hoffmanowa’s book. The main question I ask here is : why did no one until now, either in 19th-century criticism or in our contemporary criticism, mention this literary fraud before?

Relevância:

20.00% 20.00%

Publicador: