The Perron Problem for C-Semigroups

&lt;p&gt;Characterizations of Perron-type for the exponential stability of exponentially bounded C-semigroups are given. Also, some applications for the asymptotic behavior of the integrated semigroups are obtained.&lt;/p&gt;</p

Turing patterns in parabolic systems of conservation laws and numerically observed stability of periodic waves

Turing patterns on unbounded domains have been widely studied in systems of reaction-diffusion equations. However, up to now, they have not been studied for systems of conservation laws. Here, we (i) derive conditions for Turing instability in conservation laws and (ii) use these conditions to find families of periodic solutions bifurcating from uniform states, numerically continuing these families into the large-amplitude regime. For the examples studied, numerical stability analysis suggests that stable periodic waves can emerge either from supercritical Turing bifurcations or, via secondary bifurcation as amplitude is increased, from sub-critical Turing bifurcations. This answers in the affirmative a question of Oh-Zumbrun whether stable periodic solutions of conservation laws can occur. Determination of a full small-amplitude stability diagram-- specifically, determination of rigorous Eckhaus-type stability conditions-- remains an interesting open problem.Comment: 12 pages, 20 figure

Fucose Binding Cancels out Mechanical Differences between Distinct Human Noroviruses

The majority of nonbacterial gastroenteritis in humans and livestock is caused by noroviruses.Like most RNA viruses, frequent mutations result in various norovirus variants. The strain-dependentbinding profiles of noroviruses to fucose are supposed to facilitate norovirus infection. It remains unclear, however, what the molecular mechanism behind strain-dependent functioning is. In this study,by applying atomic force microscopy (AFM) nanoindentation technology, we studied norovirus-likeparticles (noroVLPs) of three distinct human norovirus variants. We found differences in viral mechanical properties even between the norovirus variants from the same genogroup. The noroVLPswere then subjected to fucose treatment. Surprisingly, after fucose treatment, the previously foundconsiderable differences in viral mechanical properties among these variants were diminished. Weattribute a dynamic switch of the norovirus P domain upon fucose binding to the reduced differencesin viral mechanical properties across the tested norovirus variants. These findings shed light on themechanisms used by norovirus capsids to adapt to environmental changes and, possibly, increasecell infection. Hereby, a new step towards connecting viral mechanical properties to viral prevalenceis taken.<br/

Characteristic function of the order statistics of the Student’s t distribution

An exact expression is established for thecharacteristic function of the order statistics of theStudent\u27s t distribution.The expression is a single infinite sum of terms involving themodified Bessel function of the second kind.It is simpler and yet more general than previously known expressions

Chromosome number of Elatine gussonei (Sommier) Brullo (Elatinaceae) and its distribution on the Maltese islands

Elatine gussonei (Sommier) Brullo is an endemic species, with a distribution restricted to the central part of the Mediterranean Basin (Maltese islands, Lampedusa, southern part of Sicily). This hydrophyte grows in rainwater pools and cavities in karstic limestone. Although the morphology has been well studied, no karyological study has been carried out, and hence this work brings the first chromosome data for the Maltese-pelago endemic E. gussonei.We have found a diploid number of 54 chromosomes in E. gussonei, which differs from the chromosome number of most of Elatine species (2n = 36). Additionally, this account gives a recent distribution of the species on the Maltese islands