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Background: Young age remains a controversial issue as a prognostic factor in breast cancer. Debate includes patients from different parts of the world. Almost 50% of patients with breast cancer seen at the American University of Beirut Medical Center (AUBMC) are below age 50. Methods: We reviewed 1320 patients seen at AUBMC between 1990 and 2001. We divided them in three age groups: Below 35, 35-50, and above 50. Data and survival were analyzed using Chisquare, Cox regression analysis, and Kaplan Meier. Results: Mean age at presentation was 50.8 years. 107 patients were below age 35, 526 between 35-50 and 687 patients above age 50. Disease stages were as follows: stage I: 14.4%, stage II: 59.9%, stage III: 20% and stage IV: 5.7%. Hormone receptors were positive in 71.8% of patients below 35, in 67.6% of patients 35-50 and in 78.3% of patients above 50. Grade of tumor was higher as age at presentation was lower. More young patients received anthracycline-based adjuvant chemotherapy. Of hormone receptor-positive patients, 83.8% of those below age 35 years, 87.76% of those aged 35-50 years, and 91.2% of those aged above 50 years received adjuvant tamoxifen. The mean follow up time was 3.7 +/- 2.9 years. Time to death was the only variable analyzed for survival analysis. Excluding stage IV patients, tumor size, lymph node, tumor grade and negative hormone receptors were inversely proportional to survival. Higher percentage of young patients at presentation developed metastasis (32.4% of patients below 35, as compared to 22.9% of patients 35-50 and 22.8% of patients above 50) and had a worse survival. Young age had a negative impact on survival of patients with positive axillary lymph nodes, and survival of patients with positive hormonal receptors, but not on survival of patients with negative lymph nodes, or patients with negative hormonal receptors. Conclusion: Young age at presentation conferred a worse prognosis in spite of a higher than expected positive hormone receptor status, more anthracycline-based adjuvant chemotherapy and equivalent adjuvant tamoxifen hormonal therapy in younger patients. This negative impact on survival was seen in patients with positive lymph nodes and those with positive hormonal receptors. [ABSTRACT FROM AUTHOR]

Characterizes nuclear microsatellites in Pinus halepensis and their inheritance in Pinus halepensis and Pinus brutia. Genetic diversity observations; Levels of heterozygosities; Genetic polymorphisms identified.

The tree flora of the Mediterranean Basin contains an outstanding taxonomic richness and a high proportion of endemic taxa. Contrary to other regions of the Mediterranean biome, a comprehensive phylogenetic analysis of the relationship between phylogenetic diversity, trait diversity and environmental factors in a spatial ecological context is lacking.We inferred the first calibrated phylogeny of 203 native tree species occurring in the European Mediterranean Basin based on 12 DNA regions. Using a set of four functional traits, we computed phylogenetic diversity for all 10,042 grid cells of 10 × 10 km spatial resolution to completely cover Mediterranean Europe. Then, we tested the spatial influence of environmental factors on tree diversity.Our results suggest that the nature of the relationship between traits and phylogeny varies among the different studied traits and according to the evolutionary distance considered. Phylogenetic diversity and functional diversity of European Mediterranean trees correlated strongly with species richness. High values of these diversity indices were located in the north of the study area, at high altitude, and minimum temperature of the coldest month. In contrast, the two phylogenetic indices that were not correlated with species richness (Mean Phylogenetic Distance, Phylogenetic Species Variability) were located in the south of the study area and were positively correlated with high altitude, soil organic carbon stock and sand soil texture.Our study provides support for the use of phylogenies in conservation biology to assess ecosystem functioning, and provides insights for the implementation of sustainable forest ecosystem management. [ABSTRACT FROM AUTHOR]

Abstract: Leaf unfolding is a key ecosystem parameter controlling carbon and water fluxes and affecting forest dynamics. This parameter is highly sensitive to temperature and, consequently, often used as an indicator of global change. In this paper, we analyzed weekly leaf unfolding dynamics for seven temperate species (Fagus sylvatica L., Acer opalus Mill., Sorbus aria L., Quercus pubescens Willd. Abies alba Mill., Pinus sylvestris L., Pinus nigra Arnold). The effects of temperature on leaf unfolding were studied in situ using several methods and proxies. First, in a spatial approach, leaf unfolding dates were measured along two altitudinal gradients situated on the north and south face of the Mont Ventoux to test altitudinal and slope effects. Second, in a temporal approach, the year effect was analyzed on the north face by comparing two contrasted years (2006 and 2007). Finally, the role of temperature was investigated directly by linking leaf unfolding patterns and temperatures recorded during the leaf unfolding process itself. Two major conclusions were obtained. First, three distinct leaf unfolding patterns were revealed: a rapid sigmoid pattern for the deciduous species group, a slow kinetic pattern for the pines and an intermediate pattern for A. alba. Second, we found an unexpected pattern of variation in the response to spatial or temporal variation of temperature. The more sensitive a species was to temperature variations between years, the less sensitive it was to temperature variations due to altitude. Finally, we discuss that these results can be correlated to two major life history traits: evergreen vs. deciduous and shade tolerant vs. shade intolerant. [Copyright &y& Elsevier]

Abstract: Our study is part of a multi-disciplinary research project aimed at stimulating debate among researchers and local managers. The central question of this multi-disciplinary research project was to better understand and manage high biodiversity value open habitats threatened with shrub encroachment and landscape closure, a common problem throughout Europe. Here, we study shrub encroachment and its impact on biodiversity conservation in Mount Ventoux, a MAB Biosphere Reserve located at the southernmost tip of the French Alps. We show how using a multi-agent modelling approach provide a valuable framework to confront two potentially conflicting conservation efforts in this mountain Mediterranean landscape, that of the within-species diversity of a tree (Abies alba, the European silver fir) and that of an endangered species (Vipera ursinii ursinii, the Orsini viper). A companion modelling approach – approach which aims at transmitting and sharing knowledge, methods and tools that help understand and strengthen the collective decision making process of stakeholders sharing a common resource – was used in order to collectively represent the main activities underway on the mountain and to have a tool to address both open landscapes rehabilitation and restoration of forest environments. The co-construction of the model allowed us to build a shared representation of the territory under study and to develop and compare alternative management scenarios with local stakeholders, both to evaluate their impact on biodiversity and to provide information for forest and grazing management practice. [Copyright &y& Elsevier]

Abstract: Diffusion is one of the most frequently used assumptions to explain dispersal. Diffusion models and in particular reaction–diffusion equations usually lead to solutions moving at constant speeds, too slow compared to observations. As early as 1899, Reid had found that the rate of spread of tree species migrating to northern environments at the beginning of the Holocene was too fast to be explained by diffusive dispersal. Rapid spreading is generally explained using long distance dispersal events, modelled through integro-differential equations (IDEs) with exponentially unbounded (EU) kernels, i.e. decaying slower than any exponential. We show here that classical reaction–diffusion models of the Fisher–Kolmogorov–Petrovsky–Piskunov type can produce patterns of colonisation very similar to those of IDEs, if the initial population is EU at the beginning of the considered colonisation event. Many similarities between reaction–diffusion models with EU initial data and IDEs with EU kernels are found; in particular comparable accelerating rates of spread and flattening of the solutions. There was previously no systematic mathematical theory for such reaction–diffusion models with EU initial data. Yet, EU initial data can easily be understood as consequences of colonisation–retraction events and lead to fast spreading and accelerating rates of spread without the long distance hypothesis. [Copyright &y& Elsevier]