Ecology of the edible dormouse (Glis glis) in a western edge population in southern Belgium

peer reviewedPopulation dynamics, diet and spatial use of the edible dormouse Glis glis were studied in a peripheral population in Belgium, on the western limit of its distribution area. The main results showed that the proportion of occupied nest boxes varied between 2 and 44 %. The dormice occupied nest boxes approximately between June and October. The densities of adults varied between 0.6 and 2.3/ha. Reproduction was observed in 2006 and 2007 but not in 2005. The results of the diet study revealed a basically herbivorous diet. Home range (MCP) of males varied from 0.68 to 1.23 ha and that of females from 0.37 to 0.71 ha. Marked individuals moved on average 252 m/night (range = 60-497 m/night). In general, these results are in accordance with those observed in other countries. Only few differences appeared and they concern mainly a smaller number of occupied nest boxes, a smaller density and a higher proportion of birds in the diet of the species

Robust double-ring junction termination extension design for high voltage power semiconductor devices based on 4H-SiC

In this study, a robust double-ring junction-termination-extension (DR-JTE) for highvoltage pn-diodes is presented and analyzed using numerical simulations. As figured out, the DRJTE reduces the electrical field at both, the edge of the single-JTE region and the mesa-transition, respectively. Thereby, due to the reduction of the electrical field, the maximum breakdown voltage is increased to 91.5% of the theoretical, parallel-plane breakdown voltage of 6.5 kV and the maximum acceptable deviation of the optimum implantation dose is twice than that of the single- JTE structure. Furthermore, due to the internal ring, the mesa-transition is shielded from the electrical field and therefore the breakdown voltage is much less affected by the angle of the mesa

Alloying of ohmic contacts to n-type 4H-SiC via laser irradiation

In this study, we present results on alloying nickel as ohmic contact material to n-type 4H-SiC via a continuous wave fiber laser with different laser beam powers and processing times. The laser system exhibits an emitting wavelength of 1070 nm and a beam propagation factor M2 smaller than 1.1. Contact resistance was determined by current-voltage measurement using two- terminal contact resistance method. The results indicate that a laser beam power of at least 100 W is mandatory to initialize contact silicidation. Although the contact resistance is improvable by longer processing times, our experiments outline the much higher impact of laser beam power to contact silicidation compared to processing time. For laser beam powers of 300 W and processing times of 0.5 s a contact resistance of 6.5 comparable to contacts alloyed in a lamp heated furnace at 910 °C for 2 min with a contact resistance of 10.3, was achieved

Genetic structure of a European forest species, the edible dormouse ( Glis glis ): a consequence of past anthropogenic forest fragmentation?

International audienceThe genetic structure of forest animal species may allow the spatial dynamics of the forests themselves to be tracked. Two scales of change are commonly discussed: changes in forest distribution during the Quaternary, due to glacial/interglacial cycles, and current fragmentation related to habitat destruction. However, anthropogenic changes in forest distribution may have started well before the Quaternary, causing fragmentation at an intermediate time scale that is seldom considered. To explore the relative role of these processes, the genetic structure of a forest species with narrow ecological preferences, the edible dormouse (Glis glis), was investigated in a set of samples covering a large part of its Palaearctic distribution. Strong and complex geographical structure was revealed from the use of microsatellite markers. This structure suggests that fragmentation occurred in several steps, progressively splitting the ancestral population into peripheral isolated ones. The fact that this structure postdates post-glacial recolonization, together with dating based on microsatellite data, supports the hypothesis that the differentiation was recent, starting around 9000 years ago, and took place stepwise, possibly up to Medieval times. This complements a classic phylogeographical interpretation based on the effect of past climate change, and supports the role of anthropogenic deforestation as a trigger of recent intraspecific differentiation