The exotic invasive plant Vincetoxicum rossicum is a strong competitor even outside its current realized climatic temperature range

Dog-strangling vine (Vincetoxicum rossicum) is an exotic plant originating from Central and Eastern Europe that is becoming increasingly invasive in southern Ontario, Canada. Once established, it successfully displaces local native plant species but mechanisms behind this plant’s high competitive ability are not fully understood. It is unknown whether cooler temperatures will limit the range expansion of V. rossicum, which has demonstrated high tolerance for other environmental variables such as light and soil moisture. Furthermore, if V. rossicum can establish outside its current climatic limit it is unknown whether competition with native species can significantly contribute to reduce fitness and slow down invasion. We conducted an experiment to test the potential of V. rossicum to spread into northern areas of Ontario using a set of growth chambers to simulate southern and northern Ontario climatic temperature regimes. We also tested plant-plant competition by growing V. rossicum in pots with a highly abundant native species, Solidago canadensis, and comparing growth responses to plants grown alone. We found that the fitness of V. rossicum was not affected by the cooler climate despite a delay in reproductive phenology. Growing V. rossicum with S. canadensis caused a significant reduction in seedpod biomass of V. rossicum. However, we did not detect a temperature x competition interaction in spite of evidence for adaptation of S. canadensis to cooler temperature conditions. We conclude that the spread of V. rossicum north within the tested range is unlikely to be limited by climatic temperature but competition with an abundant native species may contribute to slow it down

Analysis of a class of boundary value problems depending on left and right Caputo fractional derivatives

In this work we study boundary value problems associated to a nonlinear fractional ordinary differential equation involving left and right Caputo derivatives. We discuss the regularity of the solutions of such problems and, in particular, give precise necessary conditions so that the solutions are C1([0, 1]). Taking into account our analytical results, we address the numerical solution of those problems by the augmented-RBF method. Several examples illustrate the good performance of the numerical method.P.A. is partially supported by FCT, Portugal, through the program “Investigador FCT” with reference IF/00177/2013 and the scientific projects PEstOE/MAT/UI0208/2013 and PTDC/MAT-CAL/4334/2014. R.F. was supported by the “Fundação para a Ciência e a Tecnologia (FCT)” through the program “Investigador FCT” with reference IF/01345/2014.info:eu-repo/semantics/publishedVersio

Absence of Gluonic Components in Axial and Tensor Mesons

A quarkonium-gluonium mixing scheme previously developed to describe the characteristic of the pseudoscalar mesons is applied to axial and tensor mesons. The parameters of the model are determined by fitting the eigenvalues of a mass matrix. The corresponding eigenvectors give the proportion of light quarks, strange quarks and glueball in each meson. However the predictions of the model for branching ratios and electromagnetic decays are incompatible with the experimental results. These results suggest the absence of gluonic components in the states of axial and tensor isosinglet mesons analyzed here.Comment: 12 page

The role of dissipation in biasing the vacuum selection in quantum field theory at finite temperature

We study the symmetry breaking pattern of an O(4) symmetric model of scalar fields, with both charged and neutral fields, interacting with a photon bath. Nagasawa and Brandenberger argued that in favourable circumstances the vacuum manifold would be reduced from S^3 to S^1. Here it is shown that a selective condensation of the neutral fields, that are not directly coupled to photons, can be achieved in the presence of a minimal ``external'' dissipation, i.e. not related to interactions with a bath. This should be relevant in the early universe or in heavy-ion collisions where dissipation occurs due to expansion.Comment: Final version to appear in Phys. Rev. D, 2 figures added, 2 new sub-section

Ulcerative colitis: let's talk about extent

Ulcerative colitis (UC) is a chronic inflammatory disease in which clinical course varies substantially between patients. The extent of the disease is usually pointed out as one of the factors responsible for this variation. With this study, we pretended to evaluate the differences in natural history and pharmacological therapy prescription between left-sided and extended UC

Ilha das Flores, estatura e peso em crianças dos 6 aos 11 anos.

IV Expedição Científica do Departamento de Biologia – Flores 1989.0s estudos de crescimento físico humano têm-se revelado de grande interesse pois permitem conhecer as características de diferentes populações e a variabilidade existente intra e interpopulações. Mas um dos aspectos mais importantes destes estudos talvez o de, ao se analisar o estado de crescimento e tempo de desenvolvimento do indivíduo, permitir destrinçar factores que influenciam nefastamente o crescimento. As diferenças existentes entre populações são o resultado da interacção do ambiente com os factores genéticos. 0s factores ambientais influênciadores do crescimento são: nutrição, doenças, status sócio-económico, urbanismo, actividade física, stress psicológico, estado do ano e clima. A nutrição é considerado o agente mais influenciador no processo de crescimento (Eveleth, 1979; Malcolm, 1979). Neste estudo consideraram-se a estatura e o peso como os indicadores do crescimento das crianças, de idades entre os 6 e 11 anos, na sua maioria naturais da Ilha das Flores. 0s objectivos foram comparar os valores obtidos com existentes para crianças continentais, descrever a sua variação em função dos indicadores sócio-económicos: profissão do pai, número de irmãos e ordem de nascimento