Heavy-flavor dynamics in nucleus-nucleus collisions: from RHIC to LHC

The stochastic dynamics of c and b quarks in the fireball created in nucleus-nucleus collisions at RHIC and LHC is studied employing a relativistic Langevin equation, based on a picture of multiple uncorrelated random collisions with the medium. Heavy-quark transport coefficients are evaluated within a pQCD approach, with a proper HTL resummation of medium effects for soft scatterings. The Langevin equation is embedded in a multi-step setup developed to study heavy-flavor observables in pp and AA collisions, starting from a NLO pQCD calculation of initial heavy-quark yields, complemented in the nuclear case by shadowing corrections, k_T-broadening and nuclear geometry effects. Then, only for AA collisions, the Langevin equation is solved numerically in a background medium described by relativistic hydrodynamics. Finally, the propagated heavy quarks are made hadronize and decay into electrons. Results for the nuclear modification factor R_AA of heavy-flavor hadrons and electrons from their semi-leptonic decays are provided, both for RHIC and LHC beam energies.Comment: 4 pages, 2 figures (3 eps files); submitted for publication in the proceedings of "Quark Matter 2011", 23-28 May 2011, Annecy (France

Heavy-flavour and quarkonium production in the LHC era: from proton-proton to heavy-ion collisions

This report reviews the study of open heavy-flavour and quarkonium production in high-energy hadronic collisions, as tools to investigate fundamental aspects of Quantum Chromodynamics, from the proton and nucleus structure at high energy to deconfinement and the properties of the Quark-Gluon Plasma. Emphasis is given to the lessons learnt from LHC Run 1 results, which are reviewed in a global picture with the results from SPS and RHIC at lower energies, as well as to the questions to be addressed in the future. The report covers heavy flavour and quarkonium production in proton-proton, proton-nucleus and nucleus-nucleus collisions. This includes discussion of the effects of hot and cold strongly interacting matter, quarkonium photo-production in nucleus-nucleus collisions and perspectives on the study of heavy flavour and quarkonium with upgrades of existing experiments and new experiments. The report results from the activity of the SaporeGravis network of the I3 Hadron Physics programme of the European Union 7th Framework Programme

Changing asset endowments and smallholder participation in higher value markets: Evidence from certified coffee producers in Nicaragua

This paper examines the capacities of smallholders in Nicaragua to exploit new linkages to certified coffee markets following the coffee crisis. Data on livelihood assets were collected from 292 households, which were clustered to test how differences in outcomes (asset building) reflect variations in initial asset endowments. The results suggest that most households built particular elements of their asset base and increased their resilience to future shocks. However, households struggled to make effective use of the gains for intensifying their livelihoods. Of the least-endowed households, few made investments in the scale or productivity of coffee, and most continued to depend heavily on subsistence production and seasonal off-farm income for survival. In conclusion, improved market access alone, even under relatively favorable market conditions and with considerable external support, will have uncertain impacts on rural poverty if the underlying constraints on household assets and investments are not addressed concurrently

Social capital: a roadmap of theoretical and empirical contributions and limitations

The general idea of social capital is that relationships matter. In this sense, the trust, cooperation and reciprocity involved in these relationships can have a positive impact on the wealth of society by reducing transaction costs, facilitating collective actions, and lowering opportunistic behavior. This work sheds light on the different theoretical and empirical problems that a scholar is likely to face in dealing with social capital research and analysis. We propose a critical roadmap of the social capital theories and applications for a general audience, nonusers included, with particular attention to the works of political and social economists. We provide a critical debate on the different definitions and measures produced, the theoretical frameworks developed, and the empirical techniques adopted so far in the analysis of the impact of social capital on socio-economic outcomes. We turn to the limitations of these techniques and suggest some basic strategies to reduce the magnitude of these limitations

Estimation of genetic diversity and relationship in sugar beet pollinators based on SSR markers

Background: Genetic diversity studies are important for the selection of parents with a greater combination capacity that, when crossed, increase the chances of obtaining superior genotypes. Thus, 26 polymorphic simple sequence repeat (SSR) primers were used to assess the genetic diversity of 140 individual samples from 12 diploid sugar beet pollinators (pollen parents) and two cytoplasmic male sterile (cms) lines (seed parents). Eight pollinators originated from three research centers in the United States Department of Agriculture, while four pollinators and cms lines were from the Institute of Field and Vegetable Crops, Novi Sad, Serbia. Results: In total, 129 alleleswere obtained, with a mean of 3.2 alleles per SSR marker. The observed heterozygosity ranged from 0.00 to 0.87 (mean = 0.30). Expected heterozygosity and Shannon's information index were the lowest for marker BQ590934 and the highest for markers SB15s and FDSB502s; the same markers were the most informative, with PIC values of 0.70 and 0.69, respectively. Three private alleles were found in pollinator EL0204; two in pollinator C51; and one in pollinators NS1, FC221, and C93035. Molecular variance showed that 77.34% of the total genetic variation was attributed to intrapopulation variability. Cluster and correspondence analysis grouped sugar beet pollinators according to the breeding centers, with few exceptions, which indicate that certain amount of germplasm was shared, although centers had their own breeding programs. Conclusions: The results indicate that this approach can improve the selection of pollinators as suitable parental components and could further be applied in sugar beet breeding programs

Social capital and life satisfaction: a cross-sectional study on persons with musculoskeletal impairments in Hanoi, Vietnam

BackgroundSocial capital has been recognized as a major social determinant of health, but less attention has been given to social capital of persons with musculoskeletal impairments. The present study aimed to explore the associations between social capital and life satisfaction of persons with musculoskeletal impairments in Hanoi, Vietnam.MethodsA cross-sectional study was conducted in Hanoi, Vietnam. From June to July 2008, we collected data from 136 persons with musculoskeletal impairments who belonged to disabled people\u27s groups. Social capital was measured using a short version of the Adapted Social Capital Assessment Tool that included group membership, support from groups, support from individuals, citizenship activities, and cognitive social capital. Life satisfaction was measured using the Satisfaction with Life Scale. As possible confounding factors, we measured socio-economic factors and disability-related factors such as activities of daily living.ResultsAfter controlling for confounding effects, group membership remained significantly associated with the level of life satisfaction reported by the persons with musculoskeletal impairments. In particular, being an active member of two or more groups was associated with higher life satisfaction. In contrast, other components of social capital such as citizenship activities and cognitive social capital were not significant in the multiple regression analysis of this study.ConclusionsThe findings suggest the importance of considering an active participation in multiple groups toward the enhancement of the life satisfaction among persons with musculoskeletal impairments. To encourage persons with musculoskeletal impairments to have multiple active memberships, their access to groups should be facilitated and enhanced

Decentralization and Local Institutional Arrangements for Wetland Management in Ethiopia and Sierra Leone.

In Ethiopia and Sierra Leone, recent social, political and environmental transformations have precipitated the intensification of wetland use, as local people have sought to safeguard and strengthen their livelihoods. Concurrent decentralization policies in both countries have also seen the government strengthen its position at the local level. Drawing upon recent field-based evidence from Ethiopia and Sierra Leone, this paper examines the compatibility between community-based local institutions for wetland use, and the process of decentralization. It argues that decentralization has in fact restricted the development of mature local institutional arrangements, due to its intrinsically political interventionist nature

European all-cause excess and influenza-attributable mortality in the 2017/18 season: should the burden of influenza B be reconsidered?

Objectives Weekly monitoring of European all-cause excess mortality, the EuroMOMO network, observed high excess mortality during the influenza B/Yamagata dominated 2017/18 winter season, especially among elderly. We describe all-cause excess and influenza-attributable mortality during the season 2017/18 in Europe. Methods Based on weekly reporting of mortality from 24 European countries or sub-national regions, representing 60% of the European population excluding the Russian and Turkish parts of Europe, we estimated age stratified all-cause excess morality using the EuroMOMO model. In addition, age stratified all-cause influenza-attributable mortality was estimated using the FluMOMO algorithm, incorporating influenza activity based on clinical and virological surveillance data, and adjusting for extreme temperatures. Results Excess mortality was mainly attributable to influenza activity from December 2017 to April 2018, but also due to exceptionally low temperatures in February-March 2018. The pattern and extent of mortality excess was similar to the previous A(H3N2) dominated seasons, 2014/15 and 2016/17. The 2017/18 overall all-cause influenza-attributable mortality was estimated to be 25.4 (95%CI 25.0-25.8) per 100,000 population; 118.2 (116.4-119.9) for persons aged 65. Extending to the European population this translates into over-all 152,000 deaths. Conclusions The high mortality among elderly was unexpected in an influenza B dominated season, which commonly are considered to cause mild illness, mainly among children. Even though A(H3N2) also circulated in the 2017/18 season and may have contributed to the excess mortality among the elderly, the common perception of influenza B only having a modest impact on excess mortality in the older population may need to be reconsidered.Peer Reviewe