Vic Arcus

Confusion and disorder - Labrinth

Mar 01, 2010

Confusion and disorder go together in many respects. Politically…. Socially…. disorder and confusion are firm friends. But I would like to speak about disorder from a scientific point of view because in this respect as well, there tends to be confusion. And yet, disorder (or entropy) is one of the most important concepts in science. Peter Atkins (Oxford chemistry professor and author) cites the second law of thermodynamics (which is about disorder) as the reason why everything in the universe happens. And Einstein agrees: “It is the only physical theory of universal content which I am convinced will never be overthrown.” So it is worthwhile making some attempt to get to grips with disorder (or entropy) whilst avoiding confusion. We see a tendency for things to become more disordered in our everyday lives. Somehow the house does not stay … Read More

The numbers game - Labrinth

Feb 16, 2010

Biology is about big and small. Really big (a whale) and really, really small (a bacterial cell). For a beautiful visual tour of the big to the very small, I can recommend this from the Learn Genetics website (this website was recently awarded the Science prize for online resources in education). This animated web page lets you zoom from a coffee bean down to a virus and a protein. To get with the jargon its an “order-of-magnitude” thing. Like all jargon, this is a fancy way of saying something simple. Two numbers differ by an order of magnitude if one is ten times bigger or smaller than the other – its just the number of zeros before or after the “1”. For example, 1 meter is 2 orders of magnitude larger than 1 cm (1 m = 100 … Read More

Bug of the week - Labrinth

Feb 08, 2010

I love microbiology. Microbes are simpler than plants or animals – just single cells dividing and expanding in number (exponentially!). Microbes invented photosynthesis, they invented antibiotics, they even invented sex. Simple, yet stunningly diverse, they live everywhere – in the soil, in the rocks, in the sea, on your skin, in your stomach. There’s a whole community of bugs living in your stomach and it is said that every individual human on the planet has a different population of microbes in the their digestive tract and could be uniquely identified by them. So I thought that I would start a series on cool bugs and where they live. This weeks bug is called Chlorobium phaeobacteroides BS1 (microbes are given two latin-style names. The first, capitalised, signifies the genus and the second signifies the species. Often there is a … Read More

The ribo what? - Labrinth

Nov 17, 2009

In the cellular city, there is one factory which reigns supreme and it is called the ribosome. This is the molecular factory which produces proteins. It is a monolithic molecular complex which literally “translates” the information in genes (encoded by sequences of DNA and RNA) into proteins. It is also very ancient and is found in all forms of life on the planet including all bacteria, plants and animals (and us). The “translation” is very complicated because is really more than translation. For example, if I were to translate some instructions from one language to another (say Danish to English) I’m not really changing the instructions – I’m simply representing them in a different language. But if I were to translate the instructions to build a house from Danish to English and then follow this by building the house, then … Read More

Helices turn right or left - Labrinth

Oct 29, 2009

I was in the garden this weekend and I saw the new tendrils on our passion-fruit vine winding their way outwards from the main stem of the vine. The tiny passion-fruit leaders form helices which grasp onto, and wind their way around the wire which we attached to the wall. The new spring growth in the garden has lots of examples of these beautiful helical forms. There are the new spirals of the black mamaku pongas and the beans spiral their way up the netting. There is a fascinating property of helices which is worth describing. If you look at an old fashioned cork screw (which is a helix) you’ll notice that it goes in one direction. I checked our cork screw and found that it was right handed. That is, you must screw it clockwise to get it to … Read More

Cooperation as a cornerstone of evolution - Labrinth

Oct 16, 2009

In their book, The Major Transitions in Evolution, John Maynard Smith and Eors Szathmary describe 8 great evolutionary leaps which take us from individual molecules in a primordial soup, to human societies. John Maynard Smith gave an inspirational lecture at The Royal Institute on the Origins of Life shortly before his death, which you can see here. The 8 evolutionary transitions each involve “things” coming together in a cooperative way. This is not cooperation as we would intuitively think about it – groups of people getting together to achieve a certain goals (modern government is a good example in this case). The nature of the cooperation in evolution is more fundamental. As an example, the evolutionary leap to get from genes to chromosomes involves genes becoming spliced together so that groups of genes behave as a unit … Read More

The cellular phone book - Labrinth

Sep 30, 2009

The phone book for a city is a dull read. The surnames, initials and addresses for everyone who lives in a city. For the truly bored, you might find some prurient entertainment in some of the more descriptive surnames. It’s not even complete, given that a significant number of the inhabitants choose not to have their names published. However, with a bit of analysis, a phone book turns out to be quite interesting. If you were a demographer or a town planner, you could analyse the data in a phone book and combine it with a map and make some inferences about population density. You might even plot the growth of various suburbs by tracking this data over time – compare 1990’s phone book with that of today. If you collate first names with time and watch them change, it … Read More

The city and the cell - Labrinth

Sep 29, 2009

A city from space resembles a dense mosaic. Roads prescribing the polygons and curves of the myriad city blocks and parks. The city periphery is often constrained by geography: mountains to the east, a river runs through it, the sea to the west. The city plans are, in some cases, the result of the invisible hands of the town planner (for a modern city such as Canberra) which rationally demarcate residential, industrial and commercial zones. These “plans” are no less apparent for a medieval city whose organization has a vernacular and sometimes brutal history as its architect. Carcasonne is one such beautiful medieval city surrounded by walls, two thick, replete with battlements, ramparts and parapets. These defenses are a relic of more strident times when small feudal states were frequently under attack. The environment surrounding the city … Read More