In Praise of Prof. Dr. Robert Kolb On the Occasion of the Awarding of the Hermann-Sasse-Prize Werner Klän

In Praise of Prof. Dr. Robert Kolb On the Occasion of the Awarding of the Hermann-Sasse-Priz

‘He heals the brokenhearted and binds up their wounds’ (Ps 147:3): Perspectives on pastoral care

The psalmist is deeply convinced that God is a reliable addressee to whom those hurt, traumatised and grieving may turn. Churches, by their mandate to share God’s loving-kindness, are obliged to provide opportunities, counselling and pastoral care to those who suffer from violations in their lives. Representatives of the church will do so by proclaiming God’s compassion and pitifulness. This obligation is all the more important as it can be observed that Christians, congregations and churches have oftentimes been part and parcel of processes that caused harm, hurt and trauma to their members or other people

Morphometric characterisation of wing feathers of the barn owl Tyto alba pratincola and the pigeon Columba livia

<p>Abstract</p> <p>Background</p> <p>Owls are known for their silent flight. Even though there is some information available on the mechanisms that lead to a reduction of noise emission, neither the morphological basis, nor the biological mechanisms of the owl's silent flight are known. Therefore, we have initiated a systematic analysis of wing morphology in both a specialist, the barn owl, and a generalist, the pigeon. This report presents a comparison between the feathers of the barn owl and the pigeon and emphasise the specific characteristics of the owl's feathers on macroscopic and microscopic level. An understanding of the features and mechanisms underlying this silent flight might eventually be employed for aerodynamic purposes and lead to a new wing design in modern aircrafts.</p> <p>Results</p> <p>A variety of different feathers (six remiges and six coverts), taken from several specimen in either species, were investigated. Quantitative analysis of digital images and scanning electron microscopy were used for a morphometric characterisation. Although both species have comparable body weights, barn owl feathers were in general larger than pigeon feathers. For both species, the depth and the area of the outer vanes of the remiges were typically smaller than those of the inner vanes. This difference was more pronounced in the barn owl than in the pigeon. Owl feathers also had lesser radiates, longer pennula, and were more translucent than pigeon feathers. The two species achieved smooth edges and regular surfaces of the vanes by different construction principles: while the angles of attachment to the rachis and the length of the barbs was nearly constant for the barn owl, these parameters varied in the pigeon. We also present a quantitative description of several characteristic features of barn owl feathers, e.g., the serrations at the leading edge of the wing, the fringes at the edges of each feather, and the velvet-like dorsal surface.</p> <p>Conclusion</p> <p>The quantitative description of the feathers and the specific structures of owl feathers can be used as a model for the construction of a biomimetic airplane wing or, in general, as a source for noise-reducing applications on any surfaces subjected to flow fields.</p