Gibberella musae (Fusarium musae) sp. nov., a recently discovered species from banana is sister to F. verticillioides

Several strains of Fusarium isolated from banana were identified previously as F. verticillioides (Sacc.) Nirenberg but described as unable to produce fumonisin. Here we report biochemical and morphological evidence, as well as multilocus phylogenetic analyses based on elongation factor (EF-1a), calmodulin, b-tubulin, and the second largest subunit of RNA polymerase II (RPB2) sequences, indicating that these isolates represent a unique lineage in the Gibberella fujikuroi species complex related to but distinct from F. verticillioides. Together with previous results of molecular studies, as well as with results of metabolite analyses, crossing experiments, pathogenicity tests and morphological characterization, these new data indicate that these strains isolated from banana represent a new species, Gibberella musae Van Hove et al. sp. nov. (anamorph: Fusarium musae Van Hove et al. sp. nov.), which is described herei

Optimization of aluminium stressed skin panels in offshore applications

Since the introduction of Eurocode 9 specific design rules for the calculation of aluminium stressed skin panels are available. These design rules have been used for optimization of two extrusions: one for explosions and wind loading governing and one for explosions and floor loading governing. The optimized extrusions are fulfilling class 3 section properties leading to weight reductions up to 25% of regularly used shear panel sections. When the design would have been based on class 4 section properties even more weight reduction might have been reached. The failure mode depends on the height of the hat stiffeners. For sections using relatively high hat stiffeners failure is introduced by yielding of the heat affected zone. For these kind of cross sections the Eurocode 9 design rules and numerical calculations show very good agreement. For sections using relatively low hat stiffeners failure is introduced by global buckling. For these kind of cross sections Eurocode 9 gives rather conservative results

Structural application of perforated aluminium plates in a footbridge canopy

A recently designed footbridge canopy covering a concrete bridge at the Eindhoven University of Technology campus is build up by aluminium plates containing perforations. The perforations differ in concentrations, diameter and pattern. The aluminium structure was adapted to improve global behaviour especially in relation with deformation requirements. Further experimental and numerical research was carried out to investigate the failure behaviour of perforated plates loaded by compression. It is concluded that the failure behaviour of relatively thin aluminium plates in compression is very complex, even for non-perforated plates (see [8]). Further fundamental research is needed to investigate failure modes and failure loads of the perforated plates

Experimental research on pinned connections in aluminium truss girders

Aluminium truss girders are widely used in the entertainment industry. The loads on these girders, representing systems for sound and lighting, are standardised in uniform loads and/or concentrated loads. Focusing on larger spans, standard connections, i.e. welded joints between chords and braces and mechanical fasteners between girder sections, may limit the design strength of these girders. In this publication the experimental research on pinned girder section connections, which allow for an easy assembly and disassembly of the truss girders, is described and discussed. The experiments have been carried out using two different boundary conditions as well as two different securing methods. The results show a design strength which is not limited by the shear and bearing mechanism of the pinned connection. Failure is induced by cracking of a centerpoint, which is applied for easy welding procedures

Relaxation properties of the quantum kinetics of carrier-LO-phonon interaction in quantum wells and quantum dots

The time evolution of optically excited carriers in semiconductor quantum wells and quantum dots is analyzed for their interaction with LO-phonons. Both the full two-time Green's function formalism and the one-time approximation provided by the generalized Kadanoff-Baym ansatz are considered, in order to compare their description of relaxation processes. It is shown that the two-time quantum kinetics leads to thermalization in all the examined cases, which is not the case for the one-time approach in the intermediate-coupling regime, even though it provides convergence to a steady state. The thermalization criterion used is the Kubo-Martin-Schwinger condition.Comment: 7 pages, 8 figures, accepted for publication in Phys. Rev.

Effective calculation of LEED intensities using symmetry-adapted functions

The calculation of LEED intensities in a spherical-wave representation can be substantially simplified by symmetry relations. The wave field around each atom is expanded in symmetry-adapted functions where the local point symmetry of the atomic site applies. For overlayer systems with more than one atom per unit cell symmetry-adapted functions can be used when the division of the crystal into monoatomic subplanes is replaced by division into subplanes containing all symmetrically equivalent atomic positions

Identifying predictors for energy poverty in Europe using machine learning

In this paper we identify drivers for energy poverty in Europe using machine learning. The establishment of predictors for energy poverty valid across countries is a call made by many experts, since it could provide a basis to effectively target energy-poor households with adequate policy measures. We apply a “low income, high expenditure” framework that classifies households as being at risk of energy poverty to a dataset from a survey conducted at the household-level in 11 European countries with vastly different economies, cultures, and climates. A gradient boosting classifier is successfully trained on a set of socio-economic features hypothesized as predictors for energy poverty in this diverse set of countries. The classifier's internal model is analyzed, providing novel insights into the intricacies that underlie energy poverty. We find that besides the main driver - income - floor area and household size can be confirmed as predictors. Our results suggest the presence of universal predictors that are valid across Europe, and contextual ones that are governed by local characteristics. To facilitate advanced research into energy poverty in Europe, we recommend to increase and streamline household data collection efforts, both at the country- and EU-level

From Bloch model to the rate equations II: the case of almost degenerate energy levels

Bloch equations give a quantum description of the coupling between an atom and a driving electric force. In this article, we address the asymptotics of these equations for high frequency electric fields, in a weakly coupled regime. We prove the convergence towards rate equations (i.e. linear Boltzmann equations, describing the transitions between energy levels of the atom). We give an explicit form for the transition rates. This has already been performed in [BFCD03] in the case when the energy levels are fixed, and for different classes of electric fields: quasi or almost periodic, KBM, or with continuous spectrum. Here, we extend the study to the case when energy levels are possibly almost degenerate. However, we need to restrict to quasiperiodic forcings. The techniques used stem from manipulations on the density matrix and the averaging theory for ordinary differential equations. Possibly perturbed small divisor estimates play a key role in the analysis. In the case of a finite number of energy levels, we also precisely analyze the initial time-layer in the rate aquation, as well as the long-time convergence towards equilibrium. We give hints and counterexamples in the infinite dimensional case

Variation in sequence and location of the fumonisin mycotoxin niosynthetic gene cluster in Fusarium

In Fusarium, the ability to produce fumonisins is governed by a 17-gene fumonisin biosynthetic gene (FUM) cluster. Here, we examined the cluster in F. oxysporum strain O-1890 and nine other species selected to represent a wide range of the genetic diversity within the GFSC