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Bochum-Hordel, Germany

Schumacher J.,IBBP | Simon A.,French National Institute for Agricultural Research | Cohrs K.C.,IBBP | Traeger S.,IBBP | And 6 more authors.
Molecular Plant-Microbe Interactions | Year: 2015

Botrytis cinerea, the gray mold fungus, is an important plant pathogen. Field populations are characterized by variability with regard to morphology, the mode of reproduction (conidiation or sclerotia formation), the spectrum of secondary metabolites (SM), and virulence. Natural variation in bcvel1 encoding the ortholog of Aspergillus nidulans VeA, a member of the VELVET complex, was previously shown to affect lightdependent differentiation, the formation of oxalic acid (OA), and virulence. To gain broader insight into the B. cinerea VELVET complex, an ortholog of A. nidulans LaeA, BcLAE1, a putative interaction partner of BcVEL1, was studied. BcVEL1 but not its truncated versions interacts with BcLAE1 and BcVEL2 (VelB ortholog). In accordance with the expected common as well as specific functions of BcVEL1 and BcLAE1, the deletions of both genes result in similar though not identical phenotypes. Both mutants lost the ability to produce OA, to colonize the host tissue, and to form sclerotia. However, mutants differ with regard to aerial hyphae and conidia formation. Genome-wide expression analyses revealed that BcVEL1 and BcLAE1 have common and distinct target genes. Some of the genes that are underexpressed in both mutants, e.g., those encoding SM-related enzymes, proteases, and carbohydrate-active enzymes, may account for their reduced virulence. © 2015 The American Phytopathological Society. Source

Trovo M.,Ruhr University Bochum | Trovo M.,Universitatsstr 150 | Trovo M.,Federal University of Rio de Janeiro | Stutzel T.,Ruhr University Bochum
Feddes Repertorium | Year: 2012

Although diaspores and the dispersal mechanisms are keystones to tackle the evolution of Eriocaulaceae, most of the useful information is lost in taxonomic and morphological papers in a more or less unstructured way. This survey intends thus to summarize and organize the relevant information available and point new insights. Observations and photographs were made in the field, together with complementary experiments. The seeds are the smallest dispersal units and are released by the shrinkage of the pericarp. They are rarely dispersed alone but normally within the fruits or parts of it. The fruits can be released from the capitula by different systems: shrinkage of the dry receptacle and consequent release of all flowers and fruits or only the fruits, anemoballistic mechanism, catapult mechanism, and elevator mechanism. The capitula, with scapes or not, may serve as dispersal units as well. The different dispersal mechanisms seem to be deeply related to the geographic distribution of Eriocaulaceae species and may serve also to taxonomic and phylogenetic purposes. From the current stand point we encourage future studies in this area, explicitly associated with molecular studies on the population level. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Zenger C.T.,Universitatsstr 150 | Zenger C.T.,Ruhr University Bochum | Pietersz M.,Universitatsstr 150 | Pietersz M.,Ruhr University Bochum | And 4 more authors.
Computer Networks | Year: 2016

Authenticated key establishment is a central requirement for securing IoT devices. For efficiency and management reasons, it might be desirable to avoid public-key-based solutions that are ubiquitous in traditional Internet settings but have many drawbacks for resource-constrained (RC) nodes. We introduce a novel Vicinity-based Pairing (VP) mechanism that allows authenticating arbitrary 'unloaded' RC-nodes by delegating trust from already authenticated and secured, we call it 'loaded', RC-nodes. For authenticating RC-nodes, VP exploits the correlation between channel profiles from devices that are in close physical proximity. In our setting, only devices that are within a few centimetres from the 'loaded' RC-nodes are authenticated after a user initiates such a process. Subsequently, the embedded end device can extract an unique shared symmetric key with another device such as a SCADA gateway, again by exploiting channel parameters. Based on extensive experiments, we propose new techniques for extracting time-varying randomness from channel parameters for use in VP. We describe the first MITM-resistant device pairing protocol purely based on a single wireless interface with an extensive adversarial model and protocol analysis. We show that existing wireless devices can be retro-fitted with the VP protocol via software updates, i.e. without changes to the hardware. Implementation results of our embedded prototype demonstrates that the approach has the potential to dramatically reduce the cost and efforts of securing low-resource devices that are common in the IoT. © 2016 Elsevier B.V. Source

Gomes J.M.,University of Porto | Papaderos P.,University of Porto | Vilchez J.M.,Institute Astrofisica Of Andalucia Csic | Kehrig C.,Institute Astrofisica Of Andalucia Csic | And 24 more authors.
Astronomy and Astrophysics | Year: 2016

Based on a combined analysis of SDSS imaging and CALIFA integral field spectroscopy data, we report on the detection of faint (24 <μr mag/□″< 26) star-forming spiral-arm-like features in the periphery of three nearby early-type galaxies (ETGs). These features are of considerable interest because they document the still ongoing inside-out growth of some local ETGs and may add valuable observational insight into the origin and evolution of spiral structure in triaxial stellar systems. A characteristic property of the nebular component in the studied ETGs, classified i+, is a two-radial-zone structure, with the inner zone that displays faint (EW(Hα) ≃ 1 Å) low-ionization nuclear emission-line region (LINER) properties, and the outer one (3 Å Source

Barrera-Ballesteros J.K.,Institute of Astrophysics of Canarias | Barrera-Ballesteros J.K.,University of La Laguna | Garcia-Lorenzo B.,Institute of Astrophysics of Canarias | Garcia-Lorenzo B.,University of La Laguna | And 34 more authors.
Astronomy and Astrophysics | Year: 2015

We present spatially resolved stellar and/or ionized gas kinematic properties for a sample of 103 interacting galaxies, tracing all merger stages: close companions, pairs with morphological signatures of interaction, and coalesced merger remnants. In order to distinguish kinematic properties caused by a merger event from those driven by internal processes, we compare our galaxies with a control sample of 80 non-interacting galaxies. We measure for both the stellar and the ionized gas components the major (projected) kinematic position angles (PAkin, approaching and receding) directly from the velocity distributions with no assumptions on the internal motions. This method also allow us to derive the deviations of the kinematic PAs from a straight line (δPAkin). We find that around half of the interacting objects show morpho-kinematic PA misalignments that cannot be found in the control sample. In particular, we observe those misalignments in galaxies with morphological signatures of interaction. On the other hand, thelevel of alignment between the approaching and receding sides for both samples is similar, with most of the galaxies displaying small misalignments. Radial deviations of the kinematic PA orientation from a straight line in the stellar component measured by δPAkin are large for both samples. However, for a large fraction of interacting galaxies the ionized gas δPAkin is larger than the typical values derived from isolated galaxies (48%), indicating that this parameter is a good indicator to trace the impact of interaction and mergers in the internal motions of galaxies. By comparing the stellar and ionized gas kinematic PA, we find that 42% (28/66) of the interacting galaxies have misalignments larger than 16°, compared to 10% from the control sample. Our results show the impact of interactions in the motion of stellar and ionized gas as well as the wide the variety of their spatially resolved kinematic distributions. This study also provides a local Universe benchmark for kinematic studies in merging galaxies at high redshift. © 2015 ESO. Source

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