1,936 research outputs found
Impact of the Nuclear Modification of the Gluon Densities on J/Psi production in pPb collisions at sqrt(s_NN) = 5 TeV
We update our previous studies of nuclear-matter effects on J/Psi production
in proton-nucleus for the recent LHC pPb runs at sqrt(s_NN)=5 TeV. We have
analysed the effects of the modification of the gluon PDFs in nucleus, using an
exact kinematics for a 2->2 process, namely g+g->J/Psi+g as expected from LO
pQCD. This allows to constrain the transverse-momentum while computing the
nuclear modification factor for different rapidities, unlike with the usual
simplified kinematics. Owing to the absence of measurement in pp collisions at
the same sqrt(s_NN) and owing to the expected significant uncertainties in
yield interpolations which would hinder definite interpretations of nuclear
modification factor --R_pPb--, we have derived forward-to-backward and
central-to-peripheral yield ratios in which the unknown proton-proton yield
cancel. These have been computed without and with a transverse-momentum cut,
e.g. to comply with the ATLAS and CMS constraints in the central-rapidity
region.Comment: 5 pages, 16 figures, LaTeX. v2: predictions on R_CP and 3 references
added; introduction slightly extende
Towards a political economy of land: reciprocal rights and duties in private property
The paper explores some fundamental aspects of a Political Economy of Land such as the definition of rights and duties in legal and ethical terms. The increasing demands of sustainability introduces the need of a critical analysis of this institution with the purpose to explain and improve the present discussion that pursue alternative forms of appropriation and use of natural resources such as land. The responsibility involved in property rights and, thus, its conception in reciprocal terms, is present in some of the most important works of economic thought, namely Classical Political Economy and Old Institutionalism. These theories present important insights to the conception of land and its exploitation. The analysis of the legal rules that define property rights in the Portuguese case stresses the rights and duties involved in property. Besides Law, a Political Economy of Land should consider Ethics, namely Land Ethics. Therefore, the paper presents an essay for the analysis of property rights trough economic, legal and ethical concerns envisaging the design of a Political Economy of Land.info:eu-repo/semantics/publishedVersio
J/\psi\ and \psi' production in proton(deuteron)-nucleus collisions: lessons from RHIC for the proton-lead LHC run
We study the impact of different cold nuclear matter effects both on J/\psi\
and \psi' production, among them the modification of the gluon distribution in
bound nucleons, commonly known as gluon shadowing, and the survival probability
for a bound state to escape the nucleus --the nuclear absorption. Less
conventional effects such as saturation and fractional energy loss are also
discussed. We pay a particular attention to the recent PHENIX preliminary data
on \psi' production in dAu collisions at sqrt{s}=200 GeV, which show a strong
suppression for central collisions, 5 times larger than the one obtained for
J/\psi\ production at the same energy. We conclude that none of the
abovementioned mechanisms can explain this experimental result.Comment: 4 pages, 2 tables, 2 figures, contribution to Rencontres du Vietnam,
'Heavy Ion Collisions in the LHC Era', 15-21 July 2012, Quy Nhon, Vietna
Land and law: reciprocal rights and duties in private property
The paper aims to explore the property concept as one which includes the definition of rights and duties. It is important to discuss this concept in an attempt to improve the present discussion about the appropriation and exploitation of natural resources such as land in general and farm land in particular. The responsibility associated with rights and, thus, its conception in reciprocal terms, is present in some of the main works of economic thought. In developed societies legal rules play an important role in the definition of rights and reciprocal duties. This
importance justifies the contact with and the analysis of the legal rules that define property rights in a specific case – that of Portugal. The previous considerations reveal the approach adopted in property rights study and can be summed up in three words: memory, plurality and (legal) reality.
These options offer an essay for the analysis of rights in its human dimension, including, as a final note, some ethical considerations that involve man-nature relations
Interfaces in entrepreneurship development: between tradition and innovation
The linkage between tradition and innovation involves specificities and different degrees of complexity, depending on the entrepreneurial activity and economic sector. The paper adopts an institutionalist approach to study the relation between tradition and innovation through the discussion of a specific case: the introduction of innovations in cork production and transformation in a Portuguese territory: Coruche.info:eu-repo/semantics/publishedVersio
Quality criteria of best practice for the implementation of ICT – level institution
El artÃculo presenta una lista de criterios de calidad para una buena práctica en la aplicación de las TIC en instituciones latinoamericanas. La reflexión se hace a partir de los resultados de una consulta a expertos en los cursos escolares 2008-2009 y 2009-2010 entre profesores, investigadores y lÃderes de educación de América Latina y el Caribe. Las respuestas, comentarios y sugerencias permitieron la elaboración de un documento de trabajo como evidencia exploratoria al estudio experimental aún en proceso sobre nuevos ambientes de aprendizajes.The article presents a list of criteria of quality for best practice in the application of ICTs in Latin American institutions. Reflection is done based on the results of a inquiry to experts in school courses 2008-2009 and 2009-2010 among teachers, researchers and leaders of education of Latin America and the Caribbean. Responses, comments and suggestions allowed the preparation of a working paper as exploratory evidence still undergoing experimental study on new learning environments
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