4,893 research outputs found
Properties of the asymptotic nA+mB->C reaction-diffusion fronts
We discuss, at the mean-field level, the asymptotic shape of the reaction
fronts in the general nA+mB->C reaction-diffusion processes with initially
separated reactants, thus generalizing to arbitrary reaction-order kinetics the
work done by Galfi and Racz for the case n=m=1. Consequences for the formation
of Liesegang patterns are discussed.Comment: EPJ-TeX, 6 pages, 2 figs included. Statement on tails' decay revised.
References added and correcte
Phenotypic evolution and hidden speciation in Candidula unifasciata ssp. (Helicellinae, Gastropoda) inferred by 16S variation and quantitative shell traits
In an effort to link quantitative morphometric information with molecular data on the population level, we have analysed 19 populations of the conchologically variable land snail Candidula unifasciata from across the species range for variation in quantitative shell traits and at the mitochondrial 16S ribosomal (r)DNA locus. In genetic analysis, including 21 additional populations, we observed two fundamental haplotype clades with an average pairwise sequence divergence of 0.209 ± 0.009 between clades compared to 0.017 ± 0.012 within clades, suggesting the presence of two different evolutionary lineages. Integrating additional shell material from the Senckenberg Malacological Collection, a highly significant discriminant analysis on the morphological shell traits with fundamental haplotype clades as grouping variable suggested that the less frequent haplotype corresponds to the described subspecies C. u. rugosiuscula, which we propose to regard as a distinct species. Both taxa were highly subdivided genetically (FST = 0.648 and 0.777 P < 0.001). This was contrasted by the partition of morphological variance, where only 29.6% and 21.9% of the variance were distributed among populations, respectively. In C. unifasciata, no significant association between population pairwise FST estimates and corresponding morphological fixation indices could be detected, indicating independent evolution of the two character sets. Partial least square analysis of environmental factors against shell trait variables in C. u. unifasciata revealed significant correlations between environmental factors and certain quantitative shell traits, whose potential adaptational values are discussed
Standard Model Higgs boson mass from inflation
We analyse one-loop radiative corrections to the inflationary potential in
the theory, where inflation is driven by the Standard Model Higgs field. We
show that inflation is possible provided the Higgs mass m_H lies in the
interval m_min<m_H<m_max, where m_min=[136.7+(m_t-171.2)*1.95]GeV,
m_max=[184.5+(m_t-171.2)*0.5]GeV and m_t is the mass of the top quark.
Moreover, the predictions of the spectral index of scalar fluctuations and of
the tensor-to-scalar ratio practically do not depend on the Higgs mass within
the admitted region and are equal to n_s=0.97 and r=0.0034 correspondingly.Comment: 5 pages, 3 figures. Journal version+misprint fixed and added
reference to the two-loop analysis paper for convenienc
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