213,802 research outputs found
RAM function is dependent on Kapβ2-mediated nuclear entry
No full textEukaryotic gene expression is dependent on the modification of the first transcribed nucleotide of pre-mRNA by the addition of the 7-methylguanosine cap. The cap protects transcripts from exonucleases and recruits complexes which mediate transcription elongation, processing and translation initiation. The cap is synthesised by a series of reactions which link 7-methylguanosine to the first transcribed nucleotide via a 5' to 5' triphosphate bridge. In mammals, cap synthesis is catalysed by the sequential action of RNGTT (RNA guanylyltransferase and 5'-phosphatase) and RNMT (RNA guanine-7 methyltransferase), enzymes recruited to RNA pol II during the early stages of transcription. We recently discovered that the mammalian cap methyltransferase is a heterodimer consisting of RNMT and the RNMT-activating subunit, RAM (RNMT-activating mini-protein). RAM activates and stabilises RNMT and thus is critical for cellular cap methylation and cell viability. Here we report that RNMT interacts with the N-terminal 45 amino acids of RAM, a domain necessary and sufficient for maximal RNMT activation. In contrast, smaller components of this RAM domain are sufficient to stabilise RNMT. RAM functions in the nucleus and we report that nuclear import of RAM is dependent on PY nuclear localisation signals and Kapß2 nuclear transport protein
Numerical simulation of ram extrusion in short-fiber-reinforced fresh cementitious composites
No full textThis is the author's accepted manuscript. The final published article is available from the link below. First published in JoMMS in 4(10), 2009, published by Mathematical Sciences Publishers.A series of ram extrusion tests was carried out on a short-fiber-reinforced, semisolid, fresh cementitious composite. An elastoviscoplastic constitutive model is proposed for the extrudable fresh cementitious composite. It features the associative flow rule, a nonlinear strain rate-hardening law, and the von Mises yield criterion. The model is then implemented in ANSYS/LS-DYNA explicit finite element code.
Various ram extrusion processes of the fresh cementitious composite were simulated. It has been found that the extrusion load versus imposed displacement predictions agree well with the experimental results. The fresh paste flow, through the die entry and the die-land, is then interpreted in light of the evolution of the deformation and distribution of state variables, mainly based on numerical results and the ram extrusion mechanism.
The effects of extrusion ratio and extrusion velocity on extrusion load are also investigated, based on the mechanical properties of the fresh cementitious composite. The study indicates that the numerical procedure established, together with the constitutive model proposed, is applicable for describing ram extrusion of short-fiber-reinforced fresh cementitious composites, which might provide a numerical rheometric tool from which ram extrusion of elastoviscoplastic paste-like materials can be examined and quantified.Hong Kong Research Grant Council and China Ministry of Science and Technology
A functional expansion approach to the solution of nonlinear feedback systems
No full textBibliography: leaves 34-35.NSF Grant NSF-76-20860.by Ram-Nandan P. Singh and Timothy L. Johnson
CHARACTERISTIC OF FROZEN-THAWED EPIDIDYMAL SPERMATOZOA AND REFRIGERATED STORAGE OF RAM SPERMATOZOA
No full textPost-mortem spermatozoa recovery is an important technique for obtaining germplasm reserves
from genetically valuable animals or endangered species. The purpose of this study was to study
whether ram spermatozoa within epididymides stored at 4º C for 24 and 48 h remain their motility and
viability. The characteristic of ram epididymal spermatozoa after freezing and thawing was also
observed. Six pairs of ram testes with attached epididymides were used in this study. The motility of
control spermatozoa was well maintained throughout the dilution procedure (83.3±1.1, 80±1.3, and
80±1.3% for collection, Niwa and Sasaki freezing -1 extender (NSF-1 and NSF-2 groups respectively);
but declined (P<0.05) after freezing and thawing (38.3±3.1%). Motile and viable spermatozoa could be
recovered from epididymides up to 48 h of storage, although their quality declined significantly
(P<0.05) as post-mortem storage time increased (motility: 83±1.2, 67±3.0, and 46±5.1; viability:
84.2±2.4, 73±2.8, and 66.6±2.6 % for control, 24 h and 48 h group respectively). These data indicate
that ram epididymides could be stored at 4º C for 48 h when epididymal spermatozoa cannot be
immmediately collected and cryopreserved. These storage conditions might be possible to use for
epididymal sperm recovery in wild ruminants.
Keywords: epididymal spermatozoa, Freezing, ram, refrigeratio
Deterministic P-RAM simulation with constant redundancy
No full textAbstractIn this paper, we show that distributing the memory of a parallel computer and, thereby, decreasing its granularity allows a reduction in the redundancy required to achieve polylog simulation time for each P-RAM step. Previously, realistic models of parallel computation assigned one memory module to each processor and, as a result, insisted on relatively coarse-grain memory. We propose, on the other hand, a more flexible, but equally valid model of computation, the distributed-memory, bounded-degree network (DMBDN) model. This model allows the use of fine-grain memory while maintaining the realism of a bounded-degree interconnection network. We describe a P-RAM simulation scheme, which is admitted under the DMBDN model, that exploits the increased memory bandwidth provided by a two-dimensional mesh of trees (2DMOT) network to achieve an overhead in memory redundancy lower than that required by other fast, deterministic P-RAM simulations. Specifically, for a deterministic simulation of an n-processor P-RAM on a bounded-degree network, we are able to reduce the number of copies of each variable from O(log nlog log n) to Θ(1) and still simulate each P-RAM step in polylog time
RAM Legacy Stock Assessment Database v4.44
No full textRAM Legacy Stock Assessment Database version 4.44.</p
Mamba: Version Baptiste for Ram & Hadany, AmNat 2019
No full text<p>Final version for</p>
<blockquote>
<p>Ram and Hadany (2019) Evolution of Stress-Induced Mutagenesis in the Presence of Horizontal Gene Transfer. The American Naturalist.</p>
</blockquote>
sj-doc-2-ram-10.1177_07673701241238535 – Supplemental material for Le shockvertising : trajectoire historique d’une technique publicitaire controversée
No full textSupplemental material, sj-doc-2-ram-10.1177_07673701241238535 for Le shockvertising : trajectoire historique d’une technique publicitaire controversée by Thao Bui-Nguyen and Roland Canu in Recherche et Applications en Marketing (French Edition)</p
sj-docx-1-ram-10.1177_07673701241238535 – Supplemental material for Le shockvertising : trajectoire historique d’une technique publicitaire controversée
No full textSupplemental material, sj-docx-1-ram-10.1177_07673701241238535 for Le shockvertising : trajectoire historique d’une technique publicitaire controversée by Thao Bui-Nguyen and Roland Canu in Recherche et Applications en Marketing (French Edition)</p
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