Migraines, nitrogen fixation, passport application and painting chestnuts

A negative effect of awakening with a migraine is that, even when the pain is eventually dissipated by the triptans taken, one is still noise sensitive and prone to be irritable. This situation was exacerbated this morning by the neighbour's enthusiastic pressure cleaning of his guttering and roof. Mrs T. had to put up with the mood during our travel into Cambridge on a variety of errands.

En route, from the majestic height of the double decker bus, we saw that the Cherry tree lined avenue had been supplemented with new small trees, possibly false acacias (Black locust), with legume shaped flowers. This prompted the question, to be answered later, can these trees fix nitrogen like legumes? Indeed, this introduced native of the USA does have the capability of nitrogen fixation through root nodules, making them appropriate for nitrogen poor soils.

This week's New Scientist carried articles on the renewed efforts to introduce this skill into other plants. The early days of genetic engineering had held out the promise of achieving this until confronted with the reality of complex plant symbiosis with bacteria and biochemical synthesis. A more optimistic note was struck in the new article, due to the discovery that genes similar to those of legumes that facilitate the symbiosis can be found in some cereals. I did derive some amusement from a comment that one step might be to make it easier for the relevant bacteria to enter cereal roots. Unless specificity can be ensured, this might also mean an easier influx of pathogenic bacteria and fungi.

My mission was to submit a passport renewal, a task that initiated a small dance of bureaucracy at the Post Office. First was the collection of the renewal application form to be filled in. I retreated to the City Library. Oh bliss! The calm and silence at last dissipated the remnants of the negative post migraine mood. Filling in the form was relatively simple, so back to the Post Office. A short five minute queue later, I discovered that whilst the Post Office had the facility for taking photographs for driving licences and other documents, it could not take passport photos. A trip to Supa Snaps down the road captured my handsome visage in appropriate form. Another wait at the Post Office till at last, the helpful assistant completed the final stages of passport renewal submission for me.

The warm, positively close weather justified an icecream with Mrs T.

Returning home, the Chestnut trees taunted me to improve their reproduction in paint, so I took my seat, easel, paper paints and sundry accoutrements and planted myself under a tree. A couple of hours later, I had made some headway with two pictures but I must admit that my reproduction of the leaf shape is still inadequate. The solution that I am working to is a two brush-stroke generation of each leaflet of the 7 of each leaf. The problem is capturing the pointed tip, the wide ovate to lanceolate shape of the leaflet and the composition of the whole leaf. One benefit of using Chinese brush paints is that, when used diluted on appropriate paper, individual overlapping elements are clearly recogniseable. The first painted element appearing in the foreground and the subsequent overlapping painted element appears to drop behind it, with a faint watermark showing the boundaries of the first leaflet.