Earth’s ICE RECORDSIce cores preserve climate history of million of years. Most of the ice cores are taken from the ice deposited in Antarctica and Greenland. Some interesting facts…
Ice cores have been preserved in US National Ice Core Library (NICL) in Denver Colorado.
- Oldest ice core record kept there is 420000 years old.
- In the library are ice cores collected and preserved from a single hole 3.6 kilometres.
- Total length of all the ice core samples preserved in the NICL is 20 kilometres.
Dust and chemicals trapped inside the ice samples can delineate the climatic conditions prevalent in the different times in the past. Climatic Histories upto 850000 years has been recreated.
How the age is determined??
Water like any other chemical contains normal oxygen 16 (O16)atom as well as a very small fraction of oxygen 18 (O18)atoms. Water evaporation is a function of temperature. At higher temperatures O18 water evaporates more along with O16 water which means when these vapors condense will be richer in O18 . From the ratios of hydrogen
O18 and O16, temperature can be deduced.
Similarly trapped CO2 inside the cores gives the CO2 levels at different times in the past.
The humble # hashtag has turned 10 on the twitter. An average of 125 million hashtags are tweeted each day. In fact the makers of Twitter had not even added the hashtag feature as it was thought it to be too nerdy for common people. Hashtag was used earlier in c-language in the file header to include another file in the present file. For example there is a library of files called header files which are readymade pieces of software to be used in the present program.
It was the users who discovered that tweeting a term with # as prefix makes the term a clickable link. This way , not only does the post get categorised under a certain topic, it also becomes searchable.
Clicking the tag shows users all the tweets containing the tag, making it easier to follow a discussion. In tech parlance, such public tagging is called “folksonomy which is defined as “a user-generated system of classifying and organizing online content into different categories by the use of metadata such as electronic tags such as hashtag”
When the first light rain falls on the parched soil surface after dry spell of weather, the soil releases an fragrant aroma which is like magic to humans. This magical aroma has been described by many writers. So much for the feeling and aroma. But what is actually happening to create this magic.
Scientists have a explanation for it. Two Australian scientists in 1964 coined the term “PETRICHOR” for it. The word is made by shortening the two words “PETRA” meaning “ROCK” and “ICHOR” the fluid which flows in the veins of gods.
In fact soil which is mainly clay has many chemical compounds which are released by many tiny plants trapped in its lattice. These are volatile oils predominately stearic acid and palmitic acids which are fatty acids with long chain carbon structure with acid group on one end and methyl group on the other.
Also there is a chemical called “GEOSMIN” released by a soil bacteria called “ACTINOMYCETES”. Geosmin is a organic cyclic compounds with sweet smell and human nose can detect its smell down to 5 parts per trillion concentration in the air.
If the rains are accompanied by lightening and thunder, oxygen and nitrogen molecules in the air are broken down to oxygen and nitrogen radicals and recombine to form NITROUS OXIDE and OZONE. Ozone also contributes to the aroma.
So in nutshell the substances which are responsible for the aromatic earthy smell are vegetable volatile oils, geosmin and ozone.
When the rain water seeps through the soil, it enters the lattice spaces and displaces these substances out. The smells are stronger when rain is not heavy.
Note: These images are taken from Wikipedia.
The term halcyon days usually refers to the past times in one’s life when there a calm, happiness or successful period.
The term derives from the Latin word Alcyone who in mythology was daughter of Aeolus and wife of Ceyx. Her husband died during his shipwreck. The grief stricken Alcyone threw herself into the sea. After that both were transformed into halcyon birds identified as Kingfishers. For example the biological name of the white throated kingfisher is Halcyon smyrnensis.
When the birds made their floating nest on the sea, Aeolus restrained his winds and their was a period of calm of 14 days at the winter solstice, so that the eggs hatch into chicks and become birds.
The word halcyon comes from “Hals” meaning “sea or salty” and “kyon” meaning “to conceive” meaning to conceive in sea.
White throated kingfisher is a very beautiful bird. It is quite common in our area. Although going by its name, it is mainly a fish eater but it has modified its eating habits. It can catch insects, small rodents and lizards. That is why it can be found sitting on trees in the fields away from the water bodies.
Here are some pictures taken by me.
One day I was going for early morning walk in the woods. It was all quite and only sounds you heard were that of birds. Most of the trees are old and dry in the jungle. As I was walking, I heard the pecking of the dry wood. On zeroing on the source of the pecking, I saw a very small object almost resembling the color of the wood, creeping along the branch of a tree. It was pecking the bark with its beak. Meet the Brown Capped Pygmy Woodpecker.
As the name suggests it is pygmy. It just is 13 cm in size and weighs 13–17 grams. Today I saw a dry tree where a Chestnut shouldered Petronia was sitting and making sounds. As I neared for taking its photographs, I noticed the woodpecker also there. There was a standoff between them. On close observation, I noticed two holes in the tree and understood that whole tiff between them was to occupy the holes. It seemed though that woodpecker family occupied it earlier.
I could take some pictures.
DNA decoding is a powerful technique. It is a molecular level investigation tool about the life. It has helped the life scientists to say with confidence that at the molecular level, all life is identical to 99.9%. The remaining 0.1 % is all which is responsible for the vivid diversity of life.
According to one report, Neanderthals, our distant cousins, used natural drugs to alleviate the pain and diseases. 50000 years ago, they were depending on the natural cures. The ancient fossil of jaw had been studied genetically and it has been found that genetic material collected from the plaque of teeth belonged to oral bacteria and leaf pieces of medicinal compounds.
They have found methanobrevibactor which indicates abscess. These bacteria damage the teeth and cause severe pain.
Also DNA material belonging to the bacteria Enterocytozoon bieneusi. These are intestinal bacteria and cause diarrhoea.
Populus trichocarpa Popolar tree pieces which contain salicylic acid which is an ingredient of aspirin the pain killer. It would have been effective against the pain in abscess.
Penicillium rubens are food fungus and source of medical penicillin. This natural antibiotic would have been effective against gut parasites.
Most of the material has been published in the Times of India newspaper.
There are always pros and cons in the use of many things. Like drinking water. How much is optimum? There are so many answers to it. Some say one should drink 8 glass daily while some say that body itself will tell you when you need to have water. But one thing has been established beyond doubt that drinking water is good for health.
Similarly, there are many schools of thought about Smartphones. Now there are some theories about how to keep our smartphone in good health.
Following are Seven observations which are nowadays considered myths.
- Task killers help speed up the smartphone.
- Overcharging damages the phone battery. (Except heating the machine if kept covered)
- Only use charger that comes with it.
- More megapixels translate into better quality images and videos.
- Multi core processor smartphones are faster.
- Scratch guards are necessary to avoid scratches on screen.
- Android phones are packed with viruses and malawares