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It is commonly agreed that cortical information processing is based on the electric discharges (spikes') of nerve cells. Evidence is accumulating which suggests that the temporal interaction among a large number of neurons can take place with high precision, indicating that the efficiency of cortical processing may depend crucially on the precise spike timing of many cells. This work focuses on two temporal properties of parallel spike trains that attracted growing interest in the recent years: In the first place, specific delays (phase offsets') between the firing times of two spike trains are investigated. In particular, it is studied whether small phase offsets can be identified with confidence between two spike trains that have the tendency to fire almost simultaneously. Second, the temporal relations between multiple spike trains are investigated on the basis of such small offsets between pairs of processes. Since the analysis of all delays among the firing activity of n neurons is extremely complex, a method is required with which this highly dimensional information can be collapsed in a straightforward manner such that the temporal interaction among a large number of neurons can be represented consistently in a single temporal map. Finally, a stochastic model is presented that provides a framework to integrate and explain the observed temporal relations that result from the previous analyses.
Waldwachstumsmodelle sind ein ideales Werkzeug, um Auswirkungen veränderter Umweltbedingungen auf das Wachstum der Bäume aufzuzeigen. Ziel des Teilprojektes „Waldwachstumsreaktionen und Systemprozesse“ im Rahmen von ENFORCHANGE war, durch die Kombination von Wachstumsmodellen mit unterschiedlichen methodischen Ansätzen regionale Auswirkungen standörtlicher und klimatischer Veränderungen auf die Waldentwicklung zu analysieren und somit bessere Grundlagen für eine angepasste Forstbetriebsplanung zu schaffen. Anhand des physiologischen Wachstumsmodells BALANCE wurde der Einfluss der prognostizierten Klimaänderungen auf das Wachstum der Bäume abgeschätzt. Die für verschiedene Baumarten und regionaltypische Bestände gewonnenen Reaktionsmuster konnten anschließend in das managementorientierte Wachstumsmodell SILVA übertragen werden. Die Entwicklung repräsentativer Waldbestände wurde in SILVA für einen Zeitraum von 30 Jahren simuliert, wobei verschiedene Nutzungsszenarien untersucht wurden, um Handlungsspielräume und mögliche strategische Planungen für Forstbetriebe aufzuzeigen. Die gewonnenen Erkenntnisse für die praktische Betriebsplanung wurden am Beispiel des kommunalen Forstbetriebes Zittau dargestellt. Es wird deutlich, wie die Forstplanung von derartigen Szenarioanalysen profitieren kann. Die Simulationsrechnungen unter Annahme geänderter Klimaverhältnisse zeigen, dass die Bestände unter diesen Bedingungen ein verringertes Reaktionsvermögen auf waldbauliche Maßnahmen aufweisen, was insbesondere bei den Zuwächsen bemerkbar ist. Dabei haben Laubholzbestände, die bereits jetzt auf 27% der Betriebsfläche stocken, vermutlich eine Pufferwirkung und mildern die Auswirkungen der Klimaänderungen auf die Produktivität des Gesamtbetriebes ab.
1. Locating an optimal oviposition site can be a challenging task for female insects, especially when dealing with a patchy, unpredictable and ephemeral food source such as carrion. Understanding the biotic and abiotic parameters that influence the oviposition behaviour of necrophagous flies is not just of great biological importance but also essential for their application in legal investigations.
2. In this study, we monitored the oviposition activity of necrophagous flies (Calliphoridae, Sarcophagidae) using mouse carcasses in an urban (city) and a rural (mixed forest) habitat in Frankfurt/Germany over a 2-year period.
3. Over 240 sampling days, 220,963 larvae of 4 blow fly species and 1 flesh fly were sampled. The most abundant species was the blow fly Lucilia ampullacea, followed by its family members Calliphora vicina and Lucilia caesar, the flesh fly Sarcophaga caerulescens and Lucilia sericata. Up to seven environmental parameters were statistically significant predictors for a colonisation of the carcasses, leading to unique patterns of seasonal and daily oviposition activity for all five species.
4. Overall, the analysis showed that the seasonal adaption (the phenology of each species), the habitat (rural vs. urban) as well as temperature are the most important factors influencing the oviposition behaviour and activity of necrophagous blow flies and flesh flies.
The European and Mediterranean Plant Protection Organisation (EPPO) is an intergovernmental organization responsible for cooperation in plant protection in the European and Mediterranean region. It provides global distribution maps of pests, and intends to identify the areas at risk from new and emerging pests, in the framework of Pest Risk Analyses. EPPO has developed a decision-support scheme for Pest Risk Analysis (DSS) and a computer program (CAPRA) to assist pest risk analysts in running the decisionsupport scheme. Dedicated rating guidance and a Climatic Suitability Risk Mapping Decision-Support Scheme have recently been developed to guide assessors in identifying the potential area of establishment of a pest. All these tools have been developed taking into account both pest risk science available and needs of policy makers. The use of these tools and of mapping software are undertaken within the framework of EPPO Pest Risk Analyses, as illustrated through the examples of Thaumatotibia leucotreta (Lepidoptera) and Apriona germari (Coleoptera).