Butterflies ~ Too Common Yet so Unique

Courtesy: Butterfly

Biological systems use nanometer-scale shapes to produce brilliant optical properties. Morpho Sulowiskyi butterfly uses multiple layers of cuticle and air to produce unique structure which produces high contrast color change with minimal wing movement. It has been observed that Morpho butterfly fine nano-engineered structure on the wing shows highly selective vapor response by changing the angle of the wing's intricate structure to the incident light. Nevertheless apart from the butterflies, eyes of a common household fly are now being used to study the anti-reflection properties exhibited by them. House hold flies eye is an excellent structure for filtering out UV rays. Moreover these common yet unique biological structures can be used in solar cell research in case we want to filter out specific range of wavelength but the fabrication issue remains questionable because nature is quite capable of producing intricate structures which are still beyond human knowledge. Nevertheless such structures might provide the inspiration for future technological applications.

Potyrailo et. al., “Morpho butterfly wing scales demonstrate highly selective vapor pressure response”, Nature photonics, 2007.

Huang et. al., “Bio-inspired fabrication of antireflection nanostructures by replicating fly eyes”, Nanotechnology, 2008.

Huang et. al., “Controlled replication of butterfly wings for achieving tunable photonic properties”, Nanoletters, 2006.

Taare hain kya zameen par ?

Courtesy: MovieTonic

I haven't given this movie 10/10 in imdb because of the excellent direction or acting but the very fact of dealing with a new idea blew me off. Whole movie revolves around a 12 year kid and his imaginations. Acting could have been more perfect but still it was appreciable. TZP reminds me of the 80's art movies such as Sparsh and other such movies based on the neglected part of our society. May be it is quite possible that we have a soft corner for them and it helps to build up the emotional factor. I liked the beginning of the movie where alphabets tend to form different types of shapes, dancing and doing all crazy stuff. Background music and songs were not great but indeed it was worth appreciable. At least I don't see TZP as a strong contender for Oscars this year. I have huge hopes for Gowarikars Jodha Akbar simply because of its historical background and the execution of the same. Coming to TZP I wish every Parent should go and watch this movie with their kids. It is indeed a thought provoking movie with a preaching in its core. Indian subcontinent including China is facing a fierce sense of competition due to population explosion. The direct effect of the competition can be seen on small kids. This movie, if not all, but I am sure will kindle some kind fire inside the hearts of the parents. It is an eye opener.....

I hope you will like it.

Human Tooth ~ Too Common yet so Unique

Real Life Samples Taken from KJM hospital, Mumbai

Do you know that Human tooth is considered as the strongest component in a human body?

Perhaps this information you read in standard 6 while attending the general knowledge classes. Fortunately I got the opportunity to test the same during my under graduation studies. The following blog is little bit different from general entertainment flicks. In this post I have tried to explain human tooth and its properties by looking at them with the perspective of a Materials Science engineer.

Human tooth is indeed the strongest component in a human body but what fascinated me the most was its unique biomechanical properties exhibited at the dentin enamel junction commonly known as DEJ. Have you ever experienced chipping of the tooth. Yes, chipping of the tooth, not breaking of the human tooth because it is an arduous task to break a human tooth into two halves. In most of the cases tooth gets chipped from the top because cracks cannot propagate further inside the tooth due to the DEJ. I realized the fact and the reason when I was just browsing through a highly acclaimed scientific journal, Nature Publication. I came across a paper by V. Imbeni, J. J. Kruzic, G. W. Marshall, S. J. Marshall, and R. O. Ritchie (The names are according to the order appeared on the journal paper). They published the result of the experiments done on the adult human tooth to explain the unique biomechanical properties of human tooth. They found the toughness and hardness variation of the human tooth on moving away from the DEJ. If you move outwards from DEJ then obviously you are in Enamel section so you will have harder material, whereas if you are moving from DEJ towards tooth root then you are in Dentine which has lower hardness as compared to hard enamel.

fig 1: Hardness Variation from DEJ, positive axis represent
dentin whereas negative side represent enamel.

Figure 1 showing the variation of hardness with variation in distance from DEJ. As you can see hardness drastically drops on reaching the dentin region but toughness properties are superior which makes it soft as well as tough material. Human tooth is indeed a beautiful specimen at microscopic range. It has lots of beautiful pores as shown in figure 2 filled with a material which is present in our bones, you guessed it right, that material is none other than a compound of calcium and phosphorus which is commonly known as Hexa Apetite.

fig 2: SEM images of various sections of human tooth
(a) Dentin, (b) Enamel, (c) DEJ.

I really feel lucky sometimes when I think about my past. Got through JEE and studied in one of the internationally acclaimed university known as Indian Institute of Technology, Bombay commonly known as IIT and widely appreciated by IIT brand name. It gave me such a great opportunity to work with some of the high end instruments; Atomic Force Microscope is one of them. AFM images of human tooth reveal the surface morphology of the enamel and the dentin. The uneven surface due to acid etching clearly comes out when we get the result from AFM. Etching of an inorganic material is done with the help of an acid so we used Hydro-Phospheric acid to etch the mineral part of the human tooth. Figure 3 show the result of the AFM where the uneven pits formed due to acid etching which can be observed in the form of hills and valleys. It is indeed easy to represent data on paper and making comment on them but when it comes to do the experiment then you realize the real hardship behind it. It took me several weeks to get the two pictures which you can see at the bottom. It was not only hard to do the setup but it was difficult to get an appointment from the lab instructor. Yes, it took me around three months to test my samples and by that time you feel exhausted because half of your work is stuck in between due to awaited results.

fig 3: AFM images of various sections of human tooth (a) Dentin, (b) Enamel.

Indeed if I do not show the beautiful and magnificent images of cracks formed because of the Vickers Hardness Test then it would be unfair from my side. Moreover toughness test revealed why we get chipped tooth and not a broken tooth when we fall on our mouth. Figure 4 are the optical images of the enamel near DEJ on human tooth. The colorful picture is due to optical diffraction happening inside the optical microscope. If you observe the images closely then you would notice that cracks do not impinge the DEJ rather they move sidewards as if avoiding the movement inside dentin. The reason as I said earlier is the supreme and yet unique biomechanical quality of DEJ which prohibits the crack propagation inside the dentin.

fig 4: Optical Microscope Images of various indentation on human tooth
showing the direction of prorogation of crack near DEJ regions.

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Diverting-The-Traffic Strategy

Courtesy: Absolutely

Most nubies in blogging try to divert the traffic towards their blog, they use all different types of tactics such as writing about exotic topics, pasting exotic pictures or even discussing something which you know half a million people would search at the midnight. Yes, indeed it is a good way to divert the traffic but if you continue doing this then your blog will eventually turn out to be just another deceiving pornoblog having nothing except curse from frustrated deceived humans. Unfortunately I don’t have any proof about the percentage increase in HITs but of course I am eager to find out. In two words we can say ' SEX SELLS '. What about Paris Hilton controversy or Pamela Anderson real life video. I am sure they sell more than any other CDs in the internet. Nevertheless, Youtube and Xtube are the prime locations where they serve sex to the virtual world with just ' I-know-you-are-above-18-and-I-Trust-you ' type thinking. I don’t know why they ask for the age verification when they know that it is simply not going to work, may be they trust the dishonest human beings.

Not only internet industry is infected by the SELL SEX addiction but our entertainment industry is highly engrossed in the same business. Just take the example of most of the spoof movies. They cut copy paste the situations from few highly acclaimed Hollywood movies and camouflage their cheap SEX scenes over them. But it tingles’s you; you love to watch it, not the movie but the degree of deformity. Recently I saw two of the spoof movies of their kind, THE EPIC MOVIE and MEET THE SPARTANS. I found the fun factor exceptionally higher than most of the comedy movies. These movies are low budget but at the same time with full hilarious content. The way they deal with controversial Britney Spears, Angelina Jolie and of course Pamela Anderson is worth watching.

I wonder sometime which word is most frequently searched on Google. If you have any clues then you are most welcome to put your thoughts in the form of comment.