Montag, 9. Februar 2009

Article Summary:'Australia aflame'

Article Title: ‘Australia aflame’

Published in: Economist.com

Publishing date: February 9th 2009

URL: http://www.economist.com/world/asia/displayStory.cfm?story_id=13092587&source=features_box_main

Monday February 9th brought with it further news of one of the worst natural disasters in Australian history. The state of Victoria has been ravaged by wildfires, starting on the 7th, that have killed over 130 people so far, destroyed more than 750 homes and burned down 350,000 hectares of land. It overshadows the fires of January 13th 1939, on ‘Black Friday’, and February 16th 1983, on ‘Ash Wednesday’.

Recent temperatures of 45°C, alongside with strong winds and the drought in south-east Australia, created the extremely dry conditions that are the reasons for the immensity of the fires. Though some were caused by natural occurrences such as lightning, arsonists are also held responsible for a number of them. Also, it has been claimed that some have been re-lit after the fires were controlled. The fires affected national parks and farming lands 70 km from Melbourne most, yet also affected Latrobe valley; in total, most of the state of Victoria was affected by the inferno. Though the authorities had improved their co-ordination and communication skills considerably after Ash Wednesday, the conditions allowed for the rapid spread of the fire. The communities were caught by surprise, many people died trying to escape in a hurry. Already, Kevin Rudd, prime minister of Australia, promised A$10 billion for the relief of the victims of these fires.

Predictions that there would be a general increase in the Forest Fire index across south-east Australia from 34 years up to 2007 seem to be horribly true. Links have already been made to climate change; it supports the prediction that the fire seasons would begin earlier, end later and be more intense. It is not out of the question, seeing as the fires grew much more frequent since the arrival of the settlers 221 years ago.

Montag, 2. Februar 2009

Article Summary: 'Twinkle, twinkle, little laser'

Article Title: ‘Twinkle, Twinkle, little laser’
Publishing Date: Jan 21st 2009
Published on: Economist.com
URL: http://www.economist.com/research/articlesbysubject/displaystory.cfm?subjectid=348924&story_id=12966262

Water is a precious resource and a scarce one in certain parts of the world. One reason for this is that farmers do not know when and how often to water their crops and therefore do it instinctively or at set times. Automatic sprinklers make the watering itself easier, yet the problem is the amount of water that is being wasted, which is a severe problem not only for poorer countries.
Previous measures to curb water usage in drought-prone areas of the world, such as California, have not had a great effect; rising water bills and limiting the amount of water that can be used are two of them. However, a new method has been developed by Dr. Kleissel and his colleagues of the University of California, using an apparatus called a ‘scintillometer’. With the use of lasers, the amount of moisture above a crop can be detected, which allows the farmer to determine if and how much the crop needs to be watered. This is done by computing the amount the laser beam twinkles as it passes across a field towards the telescope. The more the laser beam twinkles, the more water is evaporating from the field, meaning that the plants need to be watered. This method is derived from the fact that stars appear to twinkle since the air currents caused by evaporating water make their light shimmer as it passes through the earth’s atmosphere.
This technology has found other applications too, such as measuring conditions above airport runways. This particular innovation costs between ¼ and ½ a million, meaning it is not readily accessible to the average farmer. Therefore it is currently only a method applicable to large farmers that may or may not be located in drought prone areas.

Article Summary:'Does even more than a spider can'

Article Name: ‘Does even more than a spider can’
Publishing Date: Jan 29th 2009
Published in: The Economist (print edition)

URL: http://www.economist.com/research/articlesbysubject/displaystory.cfm?subjectid=348924&story_id=13013043


Spider silk is an evolutionary marvel, it being stronger than steel yet still managing to stretch by 40% of its length before breaking. Naturally, this has gained the interest of engineers who see the possibility of an entire new family of polymers derived from spider silk.
Studies have already identified the genes that determine the different properties of spider silk; more specifically, they have identified the DNA sequences that code for the proteins that determine them. Three main properties of spider silk are its hydrophilia (affinity to water), hydrophobia (aversion to water) and the ability of its proteins to spontaneously form larger structures. Dr. Kaplan and his colleagues from Tufts University have discovered that by rearranging the order of the DNA sequences coding for these properties, several new forms of silk can be produced. Also, proteins can be made to assemble themselves in different solvents, such as propanol, resulting in thicker fibers and spheres.
These new varieties of silk could have several potential uses. The spheres of spider silk can, for example, be used as capsules for medication which would deliver the medication over a longer period than regular capsules. Silks light weight also makes it ideal to make strong components in aircrafts, for example. To what extent this technology can effectively be applied on a material not meant for human use is another question.