Search results for " Decay"
showing 10 items of 1838 documents
Total absorption γ-ray spectroscopy of the β decays of 96gs,mY
2022
The β decays of the ground state (gs) and isomeric state (m) of 96Y have been studied with the total absorption γ-ray spectroscopy technique at the Ion Guide Isotope Separator On-Line facility. The separation of the 8+ isomeric state from the 0− ground state was achieved thanks to the purification capabilities of the JYFLTRAP double Penning trap system. The β-intensity distributions of both decays have been independently determined. In the analyses the deexcitation of the 1581.6 keV level in 96Zr, in which conversion electron emission competes with pair production, has been carefully considered and found to have significant impact on the β-detector efficiency, influencing the β-intensity di…
Traits and phylogenies modulate the environmental responses of wood-inhabiting fungal communities across spatial scales
2022
Identifying the spatial scales at which community assembly processes operate is fundamental for gaining a mechanistic understanding of the drivers shaping ecological communities. In this study, we examined whether and how traits and phylogenetic relationships structure fungal community assembly across spatial scales. We applied joint species distribution modelling to a European-scale dataset on 215 wood-inhabiting fungal species, which includes data on traits, phylogeny and environmental variables measured at the local (log-level) and regional (site-level) scales. At the local scale, wood-inhabiting fungal communities were mostly structured by deadwood decay stage, and the trait and phyloge…
Genome-wide chromosomal association of Upf1 is linked to Pol II transcription in Schizosaccharomyces pombe
2021
AbstractAlthough the RNA helicase Upf1 has hitherto been examined mostly in relation to its cytoplasmic role in nonsense mediated mRNA decay (NMD), here we report high-throughput ChIP data indicating genome-wide association of Upf1 with active genes in Schizosaccharomyces pombe. This association is RNase sensitive and it correlates with Pol II transcription and mRNA expression levels. While changes in Pol II occupancy were detected at only some genes in a Upf1-deficient (upf1Δ) strain, there is an increased Ser2 Pol II signal at all highly transcribed genes examined by ChIP-qPCR. Furthermore, upf1Δ cells are hypersensitive to the transcription elongation inhibitor 6-azauracil and display Po…
Searches for lepton number violating $K^+$ decays
2019
The NA62 experiment at CERN reports a search for the lepton number violating decays K+ -> pi(-)e(+)e(+) and K+ -> pi(-)mu(+)mu(+) using a data sample collected in 2017. No signals are observed, and upper limits on the branching fractions of these decays of 2.2 x 10(-10) and 4.2 x 10(-11) are obtained, respectively, at 90% confidence level. These upper limits improve on previously reported measurements by factors of 3 and 2, respectively.
Precise branching ratios to unbound 12C states from 12N and 12B β-decays
2009
6 pages, 2 tables, 4 figures.--PACS nrs.: 21.45.-v; 23.40.-s; 27.20.+n; 21.60.De.--Printed version published Aug 3, 2009
RNA-controlled nucleocytoplasmic shuttling of mRNA decay factors regulates mRNA synthesis and initiates a novel mRNA decay pathway
2021
AbstractmRNA level is controlled by factors that mediate both mRNA synthesis and decay, including the exonuclease Xrn1 - a major mRNA synthesis and decay factor. Here we show that nucleocytoplasmic shuttling of Xrn1 and of some of its associated mRNA decay factors plays a key role in determining both mRNA synthesis and decay. Shuttling is regulated by RNA-controlled binding of the karyopherin Kap120 to two nuclear localization sequences (NLSs) in Xrn1. The decaying RNA binds and masks NLS1, establishing a link between mRNA decay and Xrn1 shuttling. Mutations in the two NLSs, which prevent Xrn1 import, compromise transcription and, unexpectedly, also the cytoplasmic decay of ∼50% of the cell…
Field-cooling experiments on the quadrupolar-glass state of (KBr)0.47(KCN)0.53
1990
The shear strain of a mixed cyanide crystal has been measured under field-cooling conditions. The time decay after field removal follows a Kohlrausch-Williams-Watts law. The results are analogous to spin glasses, except that residual permanent strains can be frozen-in.
Dynamical Scaling in Polymer Solutions Investigated by the Neutron Spin-Echo Technique
1979
Chain dynamics in polymer solutions was investigated by means of the recently developed neutron spin echo spectroscopy. — By this technique, it was possible for the first time to verify unambiguously the scaling predictions of the Zimm model in the case of single chain behaviour and to observe the cross over to many chain behaviour. The segmental diffusion of single chains exhibits deviations from a simple exponential law, indicating the importance of memory effects. Mit Hilfe der erst kurzlich entwickelten Neutronen-Spin-Echo-Spektroskopie wurde die Kettendynamik von Polymermolekulen im gelosten Zustand untersucht. - Die Methode eroffnete die Moglichkeit, zum ersten Mal fur das Einzelkette…
Unconventional ordering behavior of semi-flexible polymers in dense brushes under compression
2014
Using a coarse-grained bead-spring model for semi-flexible macromolecules which form a polymer brush, the structure and dynamics of the polymers were investigated, varying the chain stiffness and the grafting density. The anchoring conditions for the grafted chains were chosen such that their first bonds were oriented along the normal to the substrate plane. The compression of such a semi-flexible brush by a planar piston was observed to be a two-stage process: for a small compression the chains were shown to contract by "buckling" deformation whereas for a larger compression the chains exhibited a collective (almost uniform) bending deformation. Thus, the stiff polymer brush underwent a 2n…
Application of a polymer-based photocatalytic coating for the protection of limestone stones substrates: an exposure study
2022
In the last decades there have been several studies on cultural heritage regarding the performance of protective and consolidating coatings for the prevention of decay. A coating must have several characteristics such as: efficiency, breathability, and must be durable and reversible. In this research work we tried to verify the performance of a commercial protective product such as Fosbuild FBLE 200, which is composed of a TiO2 nanopowder dispersed in an aqueous solution of an acrylic polymer. This product, which exhibits depolluting, antimicrobial, water-repellent and self-cleaning characteristics, has been applied on different lithotypes such as: Carrara marble, Noto and Comiso stone and …