Extra Credit





































































































































































































































































































































































































































































































1. The Evolution of the Hand:


































































Making a Fist of It
How a dual-use bodily structure came into existence


What is a fist? 


(click here to see more information about a fist [hand])

(click here to see how to make a fist)

What interested me: 

    I was very interested in the fact that apes did not know how to manage a grasp of an object well, because I always thought they were the most capable primates that are the closest to humans. However, they cannot manage their hands very well!

Summary of the Article
     There are different names for the end of the arm for different reasons. For example, if you use this body part to hold something it's called a hand. If you use it to hit someone, it's now called a fist. Other animals, like primates, cannot use this technique however. Apes cannot grip things very well. They use a different system called a precision grip. This is when someone holds an object between the pads of the finger tips and the pad of the thumb. Another way they hold objects is called the power grip (when all of the fingers and the thumb are wrapped around the object being grasped). For the homo sapiens'  characteristic tool-crafting skills, these two grips are crucial because it has long been thought that the use of tools was the driving force behind the modern hand's proportions. The hand is, in fact, a weapon when it becomes a fist (more than teeth, claws, antlers, or horns). The hand (of even a chimp) is incapable of forming properly. Two things are crucial: 1. the way the fingers curl back on themselves, which leaves no empty space inside the fist, 2. the buttressing role of the thumb, which adds yet further stiffness. In conclusion, the fists are proper evolutionary adaptions, with their own history of natural selection.




2. Checkpoint Charlie:
Cancer Therapy
A new class of drugs is being deployed in the struggle against cancer.


What interested me: The two drugs were different. Some people were treated successfully with one or the other. 

Summary of Article
     The job of the clinic is to attack and destroy his/her patient's tumour directly. Many methods have been used to treat cancer: surgery, drugs, and radiation therapy. However on who overcomes cancer cannot fight it him/herself; thus, their doctor needs to fight the battle for them. Immunotherapy comes in here. This new system of treatment recruits a patient's immune system to attack instead of attacking cancer directly. In the treatment of advance melanoma, such "check-point-inhibitor" immunotherapy has been proved over the past three years. 







































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































More effective versions are being brought to melanoma with a drug called Ipilmumab, which locks onto and thus blocks the action of a protein. This protein, known as CTLA-4, sits on the outer membranes of immune-system cels called T-lymphocytes (existing to kill body cells that pose a threat with infected viruses, and also cancer cells). CTLA-4 calms lymphocytes and stops them proliferating, which is good when no threat is around. However, some cancer cells masters at hiding from the immune system, so a drug that switches CTLA-4 off can unleash lymphocytes in situations when they are needed but otherwise unavailable. Further antibodies development has spurred due to the success of Ipilimumab. These antibodies work by shutting down biochemical checkpoints that limit the proliferation of lymphocytes. The success of this new drugs has showed with 11% of people responding very strongly, may sound small but they have survived, in some cases, for years with no evidence of disease! Lambrolizab, as well, looks promising. More than one-third of the 135 advanced-melonoma patients whom had been treated with Lambrolizab have shrunk. Some of the patients had been previously treated, unsuccessfully, with ipilimumab, showing that these two drugs really do work in different ways! MPDL3280 is being tested in a trial open to people who have any type of metastatic or incurable tumours, who's certain treatments offer no hope. The crucial point of this trial is that who have not responded have a range of cancers, not just melanoma. 

























































































































































































































































































































































































3. Jurassic Lark
How the pterosaur caught its supper

Even though palaeoethology, which means working out how long-extinct animals behaved, is a subject that practitioners can never, thoroughly, be proved right, they have not stopped trying. Their most recent effort, which will be presented later this month to the Internation Symposium on Pterosaurs in Rio de Janeiro, is a new attempt. Michal Habib from USC, and Mark Witton from the University of Portsmouth, in Britain, are trying to work out how one of the most strange of flying reptiles of the Jurassic earned its living. Anurognathus have been known for 90 years along with it's relatives. They were size of swifts and up until today they had been thought that, like swifts, they chased around the sky after insects. This technique is known as hawking. Dr. Witton and Dr. Habib believed this theory to be wrong. They compared the Anurognathus with 36 birds and 20 bats. By using a mix of of computerised tomography and mundane measurements with callipers, they assessed the lengths, widths, thicknesses, densities and bending potential of the bones of the modern animals and compared them with those gleaned from Anurognathus fossils. They came to the conclusion that instead, the Anurognathus sat in wait for its prey, and then flied up to intercept it like a surface-to-air missile. The mouth of the Anurognathus' was similar to the mouths of nightjars (which also sally for prey!). The pterosaur's legs and wings were stronger than those of any comparable bird or bat, reinforcing the idea that they could leap rapidly into the air. Their final conclusion was that the Anurognathus did indeed feed by sallying! They also probably sallied more effectively than any living creature!

What I found interesting: Animal behavior in general is interesting to me so the most interesting was the different theories that were thought up. 




4. Marine Biology:
Finding Nemo's Role
Clownfish help their anemones breathe!
















Summary of Article

 The relationship between a clownfish and its anemone is one of the best-known. Recently, however, researchers have shown that there is more to their usual relationship of the anemone providing a tentacle guarded home and the clownfish driving off predators that would chew its protector. In 2009, a study revealed that waste excreted by clownfish provides vital nutrients to anemones. Today, researchers have also found that clownfish can boost their hosts' oxygen supplies at night as well! Anemones and clownfish live on coral reefs where the water's oxygen levels often plunge at night as photosynthesis shuts down. Joseph Szcezebak of Auburn University, Alabama, and his colleagues wondered if clownfish might do something similar for their anemones. In fact, they do. Joseph Szcezebak and his colleagues report in an upcoming edition of Journal of Experimental Biology. They will report that they studied the oxygen consumption of clownfish and anemones in the lab, in which they used special tanks which can measure oxygen levels in the water as it is pumped in an out of the tanks. For 20-minute periods, readings were taken with just a fish in a tank or just an anemone in a tank or both in a tank together. Infra-red cameras detected that something was happening. The fish came active at night when they had a anemone in the tank. They would twirl around it, push its tentacles up and down, and finally whip their tails about. The combined level of oxygen consumption when the anemone and the clownfish were together was significantly higher than when they were kept apart. Joseph Szcezebak speculates that the antics of the clownfish allowed more water to flow over the anemone which increased the amount of oxygen the anemone can collect. 

Link: http://www.economist.com/news/science-and-technology/21572738-clownfish-help-their-anemones-breathe-finding-nemos-role

 What Interested Me: I never knew clownfish had such a great relationship with their anemones. I always though that was where their home and that was it. I never knew they tried to help/protect each other.















5. Palaeontology: A Heroic Find
Shedding light on the evolution of primates

























Early phases of primate evolution fossil record is notoriously patchy so as a result, little is known about it. This causes Archicebus achilles very beneficial to paleontologists. The nearly complete skeleton of this creature was unearthed in China's Hubei province by Ni Xijun, from the Chinese Academy of Sciences in Beijing, along with his colleagues. They reported in Nature, that the 55 million year old critter was in the Eocene epoch and seems to be the most primitive relative of tarsiers (which are mouse-sized primates which now inhabit the islands of South-East Asia. The creature also appears to have moved mostly by leaping between twigs, in which it grasped with all four limbs. It hd large eye sockets, which indicate fine vision. It also had small, pointy teeth which both suggest that it hunted insects. It resembles agile (and wide eyed) tarsiers. These are the only existing primates to enjoy an exclusively carnivorous diet of small birds, bugs, along with snakes, bats and lizards. An analysis of the fossil, however, revealed some features that resemble those of anthropoids like apes, and monkeys including man. One is an anthropoid heel bone, which Dr Ni alludes to in the specimen's name. These findings imply that the split between tarsiiformes and anthropoids, which previously included to have happened 55 million years ago, must have occurred earlier! This animal is estimate to have weighed 20-30 grams and measured 71 millimeters (or about 200 millimeters including its tail!) 



















What interested me: The size of the animal was interesting. 

Link: http://www.economist.com/news/science-and-technology/21578989-shedding-light-evolution-primates-heroic-find

Magic Mushrooms
Violin-Making

Francis Schwarze noticed something unusual a few years ago. He knew that sound travels fast through healthy wood, but some fungi that he found, do not slow sound. The acoustic properties of wood so affected seem to be just what violin-makers desire. Dr. Schwarze had some violins made as a result. These violins were made from infected wood and Schwarze discovered that the sound they made sounded like a Stradivarius (a violin made by Antonio). Dr. Schwarze is now trying to standardise this fungal treatment in order to make what he calls "mycowood".  He hopes that it will endow modern instruments with the warm and mellow sounds that were found from early centuries by Antonio Stradivari (hence the name of the violin from earlier). So the master and members of his workshop used different types of wood and different chemical treatments. The period when they were active coincides with a cold spell in the European climate during 1645 and 1715 causing wood in long winters and cool summers to create the wood to be stiff (which is what a good violin needs). Treating the wood with certain fungi endows it with similar properties. Dr. Schwarze lit upon are a type of white rot and a commonly known Dead Moll's Fingers. He applied them to Norway spruce (that is used for an instrument's body) and sycamore (which is used for the ribs, back and neck). What is unusual about these different types of fungi is that that they gradually degrade the cell walls of the wood they infect-thinning them rather than destroying them completely! This leaves a stiff scaffolding through which sound waves can pass readily without compromising the wood's elasticity. After observing the fungi, Dr. Schwarze treated the planks with a gas that kills these infections. He then handed them to two master violin-makers for conversion into instruments. And it worked! A blind trial was conducted in 2009 by a British violinist in which he compared modern violins made with treated and untreated wood from the same trees with a Stradivarius made in 1711. Over half of the jury (of experts) believed that the mycowood (or the infected wood) was the Stradivarius! Tonal quality is a subjective measurement and Stradivarius violins vary in their tones. In music, however, subjective experience is what actually counts. Dr. Schwarze has cracked a problem that defeated instrument makers for 300 years: matching or even beating, the Master of Cremona! 

What interested me: Music sounds variations. 

Link: http://en.wikipedia.org/wiki/Violin










Stradivarius



Mycowood

No comments:

Post a Comment

Subscribe to: Posts (Atom)