1,072 research outputs found
Measuring beauty production in Pb-Pb collisions at the LHC via single electrons in ALICE
We present the expected ALICE performance for the measurement of the
p_t-differential cross section of electrons from beauty decays in central Pb-Pb
collisions at the LHC.Comment: 4 pages, 2 figures, proceeding of poster presentation at "Quark
Matter 2005
A boundary element method formulation based on the Caputo derivative for the solution of the anomalous diffusion problem
This work presents a boundary element method formulation for the solution of the anomalous diffusion problem. By keeping the fractional time derivative as it appears in the governing differential equation of the problem, and by employing a Weighted Residuals Method approach with the steady state fundamental solution for anisotropic media playing the role of the weighting function, one obtains the boundary integral equation of the proposed formulation. The presence of a domain integral with the fractional time derivative as part of its integrand, and the evaluation of this fractional time derivative as a Caputo derivative, constitute the main feature of the formulation. The analyses of some examples, in which the numerical results are always compared with the corresponding analytical solutions, show the robustness of the formulation, as accurate results are obtained even for small values of the order of the time derivative
Charm and beauty of the Large Hadron Collider
With the acceleration of lead nuclei in the LHC, heavy-ion physics will enter
a new energy domain. One of the main novelties introduced by the 30-fold
energy-jump from RHIC to the LHC is the abundant heavy-quark production. After
discussing a few examples of physics issues that can be addressed using heavy
quarks, we present a selection of results on the expected experimental
capability of ALICE, the dedicated heavy-ion experiment at the LHC, in the
open-heavy-flavour sector.Comment: 10 pages, 5 figures. Invited talk at Strangeness in Quark Matter
(SQM) 2004, Cape Town, South Africa, 15-20 September 2004. Submitted to J.
Phys.
Kaon and production vs Participants in Nuclear Collisions
Data on kaon and production in nuclear collisions as a function of
centrality are analysed both at AGS and SPS energy range. We compare the
results of several experiments, looking for common trend in `participant
scaling' of production yields. We find a smooth description of scaled kaon and
yields as a function of participant density. We also show a participant
density dependence of kaons and produced in the forward hemisphere for
proton-nucleus collisions.Comment: Proceedings of the International Conference on Strangeness in Quark
Matter, 20-25 July 2000, Berkeley, CA. To appear in Journal of Physics G:
Nuclear and Particle Physic
Project management guide for student project teams
Project based learning is a methodology based on studentsâ teams developing
interdisciplinary work to deliver an outcome as a result of a project. The engineering
studentsâ teams when performing project work have to adopt project management
methodologies. Assuming that the quality of the results on project work is also dependent
on the project management methodology applied and that project management is one of the
competencies to be developed during engineering degrees, this paper presents a project
management guide to be followed by studentsâ teams involved in large projects. This project
management methodology is the result of the experience of students and teachers involved
in project based learning practices in the last 6 years in the engineering school at the
University of Minho
Global analysis of the sugarcane microtranscriptome reveals a unique composition of small RNAs associated with axillary bud outgrowth
Axillary bud outgrowth determines shoot architecture and is under the control of endogenous hormones and a fine-tuned gene-expression network, which probably includes small RNAs (sRNAs). Although it is well known that sRNAs act broadly in plant development, our understanding about their roles in vegetative bud outgrowth remains limited. Moreover, the expression profiles of microRNAs (miRNAs) and their targets within axillary buds are largely unknown. Here, we employed sRNA next-generation sequencing as well as computational and gene-expression analysis to identify and quantify sRNAs and their targets in vegetative axillary buds of the biofuel crop sugarcane (Saccharum spp.). Computational analysis allowed the identification of 26 conserved miRNA families and two putative novel miRNAs, as well as a number of trans-acting small interfering RNAs. sRNAs associated with transposable elements and protein-encoding genes were similarly represented in both inactive and developing bud libraries. Conversely, sequencing and quantitative reverse transcription-PCR results revealed that specific miRNAs were differentially expressed in developing buds, and some correlated negatively with the expression of their targets at specific stages of axillary bud development. For instance, the expression patterns of miR159 and its target GAMYB suggested that they may play roles in regulating abscisic acid-signalling pathways during sugarcane bud outgrowth. Our work reveals, for the first time, differences in the composition and expression profiles of diverse sRNAs and targets between inactive and developing vegetative buds that, together with the endogenous balance of specific hormones, may be important in regulating axillary bud outgrowth
Scalar wave equation by the boundary element method: a D-BEM approach with non-homogeneous initial conditions
International audienceThis work is concerned with the development of a D-BEM approach to the solution of 2D scalar wave propagation problems. The time-marching process can be accomplished with the use of the Houbolt method, as usual, or with the use of the Newmark method. Special attention was devoted to the development of a procedure that allows for the computation of the initial conditions contributions. In order to verify the applicability of the Newmark method and also the correctness of the expressions concerned with the computation of the initial conditions contributions, four examples are presented and the D-BEM results are compared with the corresponding analytical solutions
Dinamismi e struttura della rinnovazione in tre popolamenti d'alta quota nelle Dolomiti ampezzane
Abstract: Regeneration structures and spatial patterns of European larch (Larix decidua Miller), Swiss stone pine (Pinus cembra L.) and Norway spruce (Picea abies (L.) Karst.), were analyzed in three high elevation LTER area in the Dolomites (North-Eastern Alps). Larch and spruce regeneration is mainly affected by dense forest cover and grasses competition whereas stone pine is mostly sensitive to late snow melting, fungal diseases and wild ungulate damages. The current stand and regeneration structure suggests that larch has been highly fostered in the past due to silvo-pastoral management practices. All species show a clear tendency to spatial intraspecific aggregation especially at short-distances. The spatial patterns of larch regeneration are more complex than the other two species, more heavily affected by a main factor such as the nutcracker (Nucifraga caryocatactes L.) seed dispersal for stone pine or presence of canopy gaps for spruce. However, spatial patterns of all species depend on the number of the available microsites, that often match at small distance driving the formation of small mixed and unevenaged patches. Combining the age structure and spatial pattern information we were able to better understand the small-scale patterns and processes and the role of the past disturbances on the regeneration dynamics in space and time
- âŠ