Saturday, August 31, 2013

Olive Oil and Myths

When olives are six to eight months old, they begin to turn from green to purple. This period is best suited to extract olive oil. The olives are now cleaned, coarsely crushed, with its pit and sometimes with a few leaves from the tree. It is then finely ground to a paste, to break open the cells and free their oils. The paste is then mixed for 30-40 minutes, this separates the oil droplets from the watery olive pulp and the oil droplets coalesce with each other. The paste is then squeezed, to extract oil and water. The oil is then separated by centrifuge (sometimes by other means) and filtered. The oil that is derived by the first cold pressing is called “extra virgin” oil. The oil is required to have less than 0.8% free fatty acids (more free fatty acids means oil is damaged and unstable). More oil is then extracted by heating the paste and pressing it repeatedly, but this oil is of lesser quality. “Virgin” oil has less than 2% free fatty acids. If the oil has higher, fatty acids, then the oil is refined, this removes all impurities, including flavours. Once refined, producers add a bit of “virgin” oil to give it flavour. The greenish golden hue, of virgin olive oils are due to the presence of chlorophyll and carotenoid pigments. The flavours are due to the many phenolic compounds and hexanols. The aroma is due to the many volatile molecules like; flowery terpenes, fruity esters, green smelling fatty acids found in leaves etc. The green chlorophyll that colours the oil, also can damage the oil in the presence of light. Hence these oils are kept in dark opaque cans. Unfortunately, many myths persists around olive oils. Many people, consume olive oil for the anti-oxidants it has, oblivious to the fact that higher quantities of anti-oxidants can be got from fruits and vegetables. I was once shocked to hear, some one tell me that olive oil does not have any calories! Like any other oil, it has 9 Kcal for every gram (1 tsp will have about 45Kcal). So other than flavouring your food, do not expect olive oil to work any miracles upon your health, especially when used for frying. When used for frying, most non-refined, non-hydrogenated oils are as good as olive oil.

Thursday, August 29, 2013

Treating the common cold.

Common cold has troubled mankind for centuries and mankind has put forth various reasons for the cause and has tried out various remedies to fight it off. Today we know that it is caused by a virus; Human rhinovirus (HRV). They are remarkable simple with only 10 genes (we have about 20,000 genes) and yet they enter our body, outwit our immune system and give us cold. HRV spreads by making noses run. People with colds wipe their noses, get the virus on their hands and then spread the virus onto door knobs and other surface they touch. The virus hitches onto the skin of other people who touch those surfaces and then slips into their body. Over the next few hours, by trickery, they slip into the cells that line the interior of nose, throat and lungs they then use these host cells to make copies of its genetic material and protein shells to hold them. The host cells then rip apart and the new virus escapes. HRV infect relatively few cells and cause little harm. So why do they cause such miserable experience? Blame our immune system. Infected cells release special signalling molecules, called cytokines, which attract nearby immune cells, which then make us feel awful. These immune cells create inflammation around affected area, which triggers a scratchy feeling and leads to production of a lot of mucus. So even after the virus has escaped, we have to wait for our immune system to calm down, before we can say that our cold is finally over.
There is no vaccine for cold, nor any drug that has consistently shown signs of killing the virus. Infact, some treatment for cold may be worse than the disease itself. Parents often give their children cough syrup for cold, despite the fact that it does not help. Cough syrup itself poses a wide variety of rare yet serious side effects, like convulsions, rapid heart rate and even death. Another popular treatment is antibiotics, despite the fact that they only work on bacteria and are useless against viruses.
HRV comes in many genetic variants; any drug that attacks one protein on the virus may prove useless against another variant. Every time you have a cold, it is very much possible that you have been affected by a new variant, since the body has built immune resistance to the previous strains.
Do we need a cure for common cold? HRV itself is relatively mild and most colds are over in a week. In fact HRV may offer some benefits to their human hosts. Many studies show that children who get sick with relatively harmless viruses and bacteria may be protected from immune disorders when they get older, such as allergies and Crohn’s disease. HRV may also train our immune system not to over react to minor triggers, instead directing their assaults to real threats. Perhaps we should not think of colds as ancient enemies but as wise old tutors. 

Condensed from ‘A planet of viruses’ by Carl Zimmer.

Sunday, August 25, 2013

Have you heard about the ‘Rod of Asclepius’

Have you heard about the ‘Rod of Asclepius’ – the snake wrapped around a staff that is a symbol of medicine? Many historians today believe that the snake was originally a worm, a Guinea worm to be precise- Here is the story. Since the beginning of human history, a parasitic worm called ‘Dracunculus medinensis’ or Guinea worm, has plagued people across Africa and Asia. The larvae of Guinea worm are eaten by water fleas that live in still water bodies. When people drink the water, their digestive system destroys the fleas but not the larvae. Some larvae migrate from the small intestine into the body, where they grow and eventually mate with each other. About a year after the infection, adult females, which grow about 2-3 feet long, and full of larvae themselves; make their way to the skin of the person harbouring them. Once they get to the surface, these female Guinea worms begin to secrete acid, which burns them an exit tunnel. The worm then starts to make its way out, and the acid secreted burns the human host so much that he seeks relief in cooling water. As soon as the worm sense water it emits a milky fluid full of thousands of larvae, which start the cycle all over again. In ancient times, the only effective treatment was to wrap the worm around a stick and slowly, but carefully pull it out. The process lasts for many painful weeks. If the process is hurried along too quickly, then the worm breaks, causing even more pain to the host or even death. Early doctors used a simple drawing of the worm wrapped on a stick to show they offered their services of removing the worm by wrapping then around a stick. Today this drawing evolved into the ‘Rod of Asclepius’. Since we know how Guinea worm spreads, awareness has been created about the parasites reproduction. Victims are asked to avoid water when looking for relief and potential victims are asked to avoid water that could be infected. From about 3.5 million cases 25 years ago, the worldwide infestation has today reduced to less than 10,000. 

Friday, August 23, 2013

When the world lost 10 days.

Prior to 1582, the world followed the Julian calendar, which was introduced by Julius Caesar, who borrowed it from the Egyptians. But this calendar, assumed one year to be 365.25 days, while in actual a solar year- the time required for the earth to complete an orbit around the sun is 365 days 5 hours 48 minutes and 46 seconds. This is 11 minutes 14 seconds less than 365.25. As a result, dates on the calendar gradually lost their intended relation to solar events and seasons. The vernal equinox which was fixed by the first council of Nicaea, as March 21 was actually occurring on March 11, due to the accumulating inaccuracy of the Julian calendar.
So in 1582, Pope Gregory XIII, introduced the reformed calendar, which we now know as the Gregorian Calendar. To adjust the dates, Pope Gregory ordained that October 4 was to be followed by October 15. The leap years of the old calendar were readjusted and to prevent the accumulation of another 11-minute a year discrepancy, the Gregorian calendar omitted the leap day from years ending in hundreds unless they were divisible by 400. This is the calendar that we still follow.
There was a lot of resentment from many countries, simply because the reform had come from Rome. Protestant England and American colonies refused to go along and they accepted it only in 1752.
Back in 1582, when Pope Gregory took ten days out of the calendar, there had been grumbling and confusion. Servants demanded their usual full monthly pay for the abridged month and employers refused. People objected to their life being shortened by a Papal decree.

In China the revolution of 1911 introduced the Gregorian calendar, alongside the Chinese one. Until well past 1900 Russia used the Julian calendar and lagged to Gregorian calendar by weeks. This lag explains why the “October Revolution” that brought Vladimir Lenin and Bolsheviks to power in 1917 actually occurred in November.  

Wednesday, August 21, 2013

We exist- courtesy viruses.

We all believe that viruses are the scourge of mankind, their very mention reminds us of illness and death. But viruses are probably the most misunderstood things on earth, taxonomist are unsure if they are even living or non-living. A few of the millions of species of viruses that exist on earth give them a bad name. Viruses have saved more people than killed them. Marine viruses are the most infectious viruses of all, not to humans but to microbes in water. Every day, about half the bacteria in the world’s oceans are killed by them and humans indeed benefit from their deadliness. Cholera is caused by blooms of waterborne bacteria called Vibrio. But Vibrio are host to a number of phages (virus that infect bacteria). When the population of vibrio explodes, it causes a cholera epidemic. But this explosion also results in the multiplication of phages. The phage population rises so quickly that it kills the Vibrio faster than the microbes can reproduce. The bacterial boom subsides and the cholera epidemic fades away.  A large amount of the oxygen we breathe is also a gift from viruses. An ocean bacterium called Synechococcus, carries out about a quarter of the worlds photosynthesis. The protein that carries out the light harvesting is actually from a virus. Scientists have even found free-floating viruses with photosynthesis genes, searching new hosts to infect. For every 10 breath you breathe, one of those breaths comes courtesy of viruses. Viruses also control the temperature on earth. Algae and photosynthetic bacteria churn out half our oxygen supply. Algae also release a gas called dimethyl sulphide that rises into the air and seeds clouds. These clouds reflect incoming sunlight back into outer space cooling the planet. The viruses check the algae growth and that keeps our planets thermostat at the right temperature. As you just read, viruses have earned a bad reputation, but they contribute more to life than we appreciate. 

Monday, August 19, 2013

How a slice of meat gave birth to the science of Radiology.

When the Nazi’s came to power in Germany, they seized all the wealth and assets belonging to Jews and their sympathisers. So in 1930’s two German scientist, Max von Laue and James Frank sent their Nobel Prize medals to Niels Bohr for safekeeping. Bohr kept it at his institute in Denmark, but by August 1940 the Nazi storm troopers were knocking the doors of the institute. Desperate to hide the medals, Bohr asked his colleague Gyorgy Hevesy to dissolve the gold medals. To do this Hevesy used ‘aqua regia’ – a mix of nitric and hydrochloric acids that fascinated alchemist because it dissolved “royal metals” like gold. Hevesy managed to complete this job just in time. When the Nazi’s ransacked Bohr’s institute for loot, they left the beaker of orange aqua regia untouched. In 1943, Hevesy fled Denmark, but returned back to the institute after the war. To his surprise he found his beaker intact on a shelf. Hevesy precipitated the gold and Nobel academy later recast the medals for Franck and Laue. If you haven’t heard of Gyorgy Hevesy, then you need to read this. In 1910 Hevesy arrived in England from Hungary are worked under Rutherford on radioactivity. Hevesy was staying in a boarding house and after noticing patterns of meals served, Hevesy grew suspicious of the food served there. He suspected that his landlady was recycling the leftover food and he confronted her with his fears. The landlady denied it, and Hevesy decided to seek proof. So one night Hevesy took some extra serving of meat during dinner and when the landlady’s back was turned he sprinkled some radioactive lead on the meat which he had got from his lab. After dinner, the lady collected the leftovers as usual. The next day Hevsey bough home a radiation detector, from his friend Hans Geiger (today we call it the Geiger counter) and waved it over that night’s dinner. The Geiger counter went berserk and Hevesy confronted his landlady with the evidence. The lady supposedly was charmed at being caught so cleverly, with the latest tools of science. Hevesy, had another idea, instead of sprinkling the lead on dead tissue (cooked meat), he began musing over the possibility of injecting minute quantity of his radioactive lead into living creatures. Since the lead would emit radiation, he could actually track the molecules inside veins and organs, with an unprecedented degree of resolution. Hevesy had discovered elemental tracers, giving birth to the field of radiology. In 1920 Hevesy left for Copenhagen to study under Niels Bohr. Here along with physicist Dirk Coster he discovered element 72, Hafnium. Hevesy was repeatedly nominated for the Noble Prize, for the discovery but the political bickering, prevented him from getting one until 1943. Probably the ‘aqua regia’ stunt did finally help him. 

Saturday, August 17, 2013

A rarely told story about Vaccination.

In ancient India and China, it was known that people could protect themselves from smallpox by taking scabs from a victim, crushing them into a powder, and swallowing or scratching it into the skin. This unsavoury sounding practice called ‘variolation’ was prevalent in India and slowly spread to the western world in around 1600 AD. The practice though was not widely adopted, because there was a chance of accidently contracting full-blown smallpox and dying. In 1774, a smallpox epidemic broke out in Dorset County, England. A prosperous farmer called Benjamin Jesty, who lived in Dorset, was worried for his family. Although unproven, it was a well known fact in the farming community that milkmaids, who contacted cowpox, were never affected by the deadly smallpox. Cowpox caused pustules on cow udders and reduced milk production. It also caused pustules on milkmaid’s skin, along with fever and headaches. But they would recover in a few days. Two of Jesty’s servants had been infected with cowpox and despite caring for two boys, with small pox, they never contracted smallpox. Jesty had this fact in mind and he decided to take a leap of faith. He took his family to Farmer Elford’s pasture, which had a cow with cowpox. Jesty then took his wife’s stocking needles, dipped its tip on an open cowpox lesion and then inoculated his entire family with the infectious cowpox material. Jesty’s family survived the epidemic and his two sons remained free of smallpox for the rest of their lives. People viewed Jesty’s action of mixing human and animal substances as “abomination” against God. He was scorned, ridiculed and even pelted with stones. As a young boy, Edward Jenner too had heard about cowpox protecting people from smallpox. In 1772, after completing his medical training the 23 year-old Jenner was still intrigued by the connection. Unfortunately no one had studied it and so Jenner began collecting case reports of people who had been infected with cowpox. When he presented his case study to his medical colleagues, they insisted that his ridiculous idea was merely an old wives’ tale. Undiscouraged, Jenner took matters in his own hands and on May 14, 1796 performed the first vaccination on eight year old James Phipps. Jenner inoculated the boy with infectious cowpox “matter” taken from the hand of a milkmaid named Sarah Nelmes, who had picked up the infection from a cow named Blossom. Just like Benjamin Jesty, Jenner too faced criticism and ridicule and his data was not accepted by the medical community. In 1798, there was another outbreak of smallpox and Jenner inoculated several children, and all of them survived the outbreak. Rather than approach the medical community, Jenner published his findings in a self-published 64 page paper, in which the word ‘vaccination’ was first used. The practice of vaccination began to spread really fast and within a few years vaccination was administered not only in England but also throughout Europe and America. Vaccination for small pox continued for years and on October 26 1977, a hospital cook in Merka, Somalia became the last person to be infected by small pox. Smallpox became the first disease to be completely eliminated from the face of the earth.

Friday, August 16, 2013

A village that made periodic history

In 1701, a teenager named Johann Friedrich Bottger, was attracting crowds on the streets of Poland. He was converting two silver coins into a single gold coin. It was so convincing to the local population, that the story of the boy reached the King of Poland; Augustus the Strong. The boy was hauled before the king and locked into a castle and asked to make gold for the king. Bottger could not meet the kings demand, since his alchemy, like you guessed, was a well woven trick. The king ordered Bottger to be hanged. Desperate to save his life, Bottger claimed he knew how to make porcelain.
Those days, Europe was smitten by porcelain, which was imported from China. The manufacture was a Chinese secret and the Europeans were desperate to break it. It was said that any king who could make porcelain, would wield great power and wealth. King Augustus had a man called Ehrenfried Walter Von Tschirnhaus, researching on porcelain; Bottger was made Tschirnhaus’s assistant. Tschirnhaus, had with him an oven which could reach a temperature of 3000F. This allowed them to melt and analyse porcelain. Soon the duo discovered the secret; one a white clay called Kaolin and secondly, they learnt that porcelain glaze and pottery had to be cooked together and not separately, like it was done elsewhere. The king was presented with the technique and he dreamed of becoming the most influential monarch of Europe. This also meant that the king had to preserve the secret, so now Bottger was locked up under tighter security, with all dreams of freedom blown away.

But the secret of porcelain leaked and people all over Europe started making it and even tinkering and improving it. Mines were opened all over Europe, to feed the burgeoning industry of porcelain. In 1780 a mine in Stockholm, on the isle of Ytterby (pronounced it-er-bee) was opened. Intriguingly the rocks at Ytterby produced exotic pigments and coloured glazes when processed. Today, anyone coming across such a property will first suspect lanthanides, but those days, no one had heard about them. Those days a chemist named Johan Gadolin, had created quite a name for himself as a geochemist. He lived in Finland, across the Baltic Sea from Stockholm. Amateur geologist began shipping unusual rocks from Ytterby to him to get his opinion. Little by little through Gadolins publication, the world began to hear about this remarkable little quarry. Soon chemist began visiting these rocks, and one by one new elements started to be discovered. Today six elements in the Periodic table are named after this little hamlet; more than any person or place or thing. It was the inspiration for Ytterbium, Yttrium, terbium and erbium. More elements kept popping out but chemist ran out of alphabets (‘rbium’, does not sound right). So holmium was chosen after Stockholm and thulium after the mythic name for Scandinavia. Today the small town of Ytterby is a pilgrimage, spot for periodic table fans.

Wednesday, August 14, 2013


In 1952, Per-Ingvar Branemark, a Swedish doctor was studying how bone marrow produces new blood cells. His study subject were rabbits, and to watch this production directly, Branemark had made small openings in the femurs of rabbits and covered the opening with an paper thin titanium “window”, which was transparent to strong light. Once the observation was completed, Branemark, wanted to remove the expensive titanium and use it on other rabbits. But when he tried to remove the metal, he realised that it would not budge and had steadfastly bound to the bone. The same thing repeated in his other experiments, titanium always bound tightly to the rabbit’s femur. An idea dawned on Branemark, which made him forget his blood cell study and revolutionised the field of prosthetics. Doctors had always wanted to replace broken limbs and bones of people with something reliable. Despite all efforts, no one was able to integrate metal or wood into the body, because the immune system rejected any such attempts. Whether it was gold, Zinc, magnesium or chromium-coated pig bladders, the blood cells always surrounded the foreign matter and wrapped it with fibrous collagen. Within a few months of implantation, the new appendage would be covered in collagen and slip or snap free. Yet, Branemark found that some reason titanium, was ignored by the blood cells and triggered no immune response. It also fooled the body’s osteoblasts or bone forming cells, into attaching themselves to it as if there was no difference between the two. Since 1952, titanium has been used for implanted teeth, screwed on bones, replaceable hip sockets and many more other body parts. 

Tuesday, August 13, 2013

Why do some vegetables and fruits discolour after being cut ?

Freshly harvested vegetables from your garden always taste better, than the one purchased from a shop. Once a vegetable is harvested it begins to change (except hibernating plant parts like onions and potatoes). One a vegetable is harvested, it is cut off from its source of nutrients. So it starts to consume itself and accumulates waste products, hence the flavour and texture starts to change. Some vegetables lose half their sugar in a few hours after harvest and they either convert it to starch or use the energy to stay alive. Some vegetables lose the water pressure in their cells and become limp and chewy. Hence freshly harvested vegetables are full-flavoured than store bought produce, which is usually days to weeks from field.
Many fruits and vegetables, like banana, potatoes, apples and brinjal quickly develop a brown or red discoloration when cut or bruised. This is part of the plants defence mechanism, to protect itself from microbes when it is cut. This discolouration is caused by three chemical ingredients: 1 and 2 ringed phenolic compounds, certain plant enzymes and oxygen. When the intact fruit is cut, the phenolic compounds from the damaged cells vacuole (a storage bag, present in every plant cell) mixes with enzymes of the cells and oxygen in air and form light absorbing clusters. In nature when insects or microbes damage the cell, these phenolic compounds attack the invaders own enzymes and membranes. The brown pigments we see are essentially spent weapons. Though the browning is only on surface and does not affect flavour, for visual appeal you can reduce it by following methods. 1. Coat the surface with lemon juice, the browning enzyme works very slowly in acidic condition 2. cool the cut pieces below 4c, its slows down the reaction time. 3. Immerse it in cold water. The water limits the availability of oxygen and the cold temperature reduces reaction time. 
The enzyme that causes this fruit discolouration has a special use- it can convert stinky chemicals in our breath to odourless molecules. So eating an apple after a meal, can not only keep the doctor away, but also bad breath away.

Trivia: Methanethiol is the molecule that causes garlic breath- it is related to the same chemical that gives odour to skunk spray. 

Monday, August 12, 2013

Why home made yogurt is better than commercially available yogurt .

The sugar Lactose is unique, in nature it is almost found nowhere else but in milk. This also means, only a few microbes have the necessary enzymes to process milk, that is, digest lactose, and extract energy from it by converting it into lactic acid. This lactic acid is then released into the milk, where it accumulates and retards the growth of other microbes. There are two major groups of lactic acid bacteria. The smaller genus of Lactococcus, which is primarily found in plants. The other is the 50 or so members of Lactobacillus, which are found both in plants and in animals, including human mouth, digestive tract, and vagina. Prior to the start of industrial production of yogurt and buttermilk, humans traditionally left the milk overnight. This naturally fermented the milk, with bacteria like – Lactobacillus fermentum, L. acidophilus, L. brevis, L. plantarum and L. casei. These bacteria take residence in our intestine and shield the intestinal wall, secret antibacterial compounds, boost the body's immune response to particular disease microbes and reduce the production of potential carcinogens. Today the standard industrial yogurt and buttermilk used specialized bacteria that grow well in milk but can't survive inside the human body. Therefore, we do not receive the same benefit and protection the traditionally made yogurt provided. Even the intestines of an infant are colonized by lactic acid bacteria- the Bifidobacteria. These are fostered by breast milk and produce various antibacterial substances, providing protection to the infant. 

On a totally unrelated note-, the famous holes of Swiss cheese are because of a bacterium called Propionibacteria. Propionibacter shermanii, which is used as a starter in Swiss cheese, consumes the cheese's lactic acid during ripening and converts it into propionic acid, acetic acid and carbon-dioxide gas. The carbon-dioxide forms bubbles, or the holes in the cheese. The cheese ripens at 24°c as it is the ideal temperature for Propionibacteria. This warm temperature also is a reflection of the fact that the bacteria originally lived in human and animal skin. Today at least three species of Propionibacteria inhabit our oily skin, the most famous P. acnes, which live in our plugged oil glands.

Sunday, August 11, 2013

The first mammoth and dinosaur fossils, meet the modern men.

During the 18th and 19th Century, the general feeling among the Europeans was that the new world (America) was inferior in all ways to the old world (Europe). This assertion reached its peak when the French naturalist, Comte de Buffon, in his book ‘Histoire Naturelle’ published that the new world was a land where the water was stagnant, the soil unproductive and the animals without size and vigour. Their constitution weakened by the noxious vapours rising from its rotting swarms and sunless forest. The native Indians lacked virility, have no beard or body hair and no ardour for the female. The Dutchman Comeille de Pauw wrote in his work, Recherches Philosophiques sur les Americains’ that the native Americans were not only reproductively unimposing, but so lacking in virility that they had milk in their breasts. Naturally such views were met with furious rebuttals from American writers. Thomas Jefferson, asked his friend General John Sullivan to send twenty soldiers into the northern woods to find a bull moose to present it to Buffon as proof of the stature and majesty of American quadrupeds. After two weeks the soldiers tracked and hunted down a suitable subject, but unfortunately the moose lacked the imposing horns that Jefferson wanted. So Sullivan attached a rack of antlers from an elk. Who in France after all would know?
Meanwhile, in Philadelphia, bones of a giant elephant like creature were being assembled. The creature was named ‘American incognitum’ now called the mammoth. The bones were first discovered at Big Bone Lick in Kentucky and soon found all over America. It looked like America was once home to these massive creatures. In their keenness to silence the Europeans (particularly Buffon) American naturalist got slightly carried away. In their description of the “incognitum” they overestimated its size by a factor of six and gave it frightening claws, which in fact came from Megalonyx, or giant ground sloth, found nearby. They convinced themselves that the creature had the agility of a tiger and portrayed it in illustrations as pouncing on its prey from boulders with feline grace. When tusks were discovered, they were forced into the animals head in many inventive ways. One restorer screwed them upside down to look like fangs of a Sabre tooth. But Buffon was not impressed; he cheerfully seized the fact of its extinction and proclaimed that the very fact that the creature was extinct was proof of America’s degenerate nature. 

Buffon died in 1788, meanwhile in 1787 someone discovered a enormous thighbone in New Jersey. The bone is today believed to have belonged to ‘Hadrosaur’ (a large duck billed dinosaur). At that time, dinosaurs were unknown. The bone was sent to Dr. Caspar Wistar, who presented it to American philosophical society. The discovery excited little interest and the bone was put in a store room and eventually disappeared. So the first dinosaur bone ever found was also the first to be lost. 

Saturday, August 10, 2013

Fluke start to a deadly war.

It is well known that the trigger for the First World War was the assassination of Archduke Franz Ferdinand. But the assassination itself was quite a chanceful event. Serbian nationalists wanted to break away from Austria-Hungary, and form part of a Greater Serbia. To achieve this they decided to assassinate leading Austro-Hungarian figures. The assassination of Franz Ferdinand was set to take place on 28th June. Six assassins were positioned along the route of Ferdinand’s motorcade. As the cars passed, the first two assassins did nothing, presumably they lost their nerve. The third assassin, Nedeljko Cabrinovic, did throw a bomb but it missed, and instead blew up the next car in the motorcade. Twenty people were wounded. The crowd panicked, Cabrinovic quickly swallowed his suicide pill and jumped into the River Miljacka, but the river was only a few inches deep and the pill only succeeded in making him vomit. He was dragged out beaten to pulp, before being handed over to the police (he supposedly shouted “I am a Serbian Hero”).
Despite the attack the Archduke decided to continue with the visit. He attended a town hall reception, and then the motorcade proceeded for the hospital, to visit those wounded by the bomb. Enroute the cars took a wrong turn, and so Ferdinand’s driver reversed into an alley, to turn around. There, the car happened by chance to pull up alongside one of the terrorist’s. His name was Gavrilo Princip. Gavrilo was himself in the wrong place, having been given faulty directions. Spotting his opportunity, Gavrilo quickly fired his gun into the car, killing both Ferdinand and his wife Sophie.

The assassination triggered the outbreak of the First World War.

Friday, August 09, 2013

How to make sweet potato sweeter.

If you enjoy eating boiled sweet potatoes like me, then here is a trick to make the potato sweeter, without adding anything. Sweet potato, sweeten during cooking because of an enzyme which reacts with the starch of the potato and breaks it down. The starch is broken down to maltose, a sugar made of two glucose molecules, and it is about 30% as sweet as table sugar. Soggy sweet potatoes convert as much as 75% of their starch to maltose and they taste like sugary jelly. This conversion from starch to maltose starts when the water temperature is 57c and stops when the rising heat denatures the enzyme at 75c. So for a really sweet potato, bake it slowly, rather than rapid cooking in steam or in pressure cooker. Rather than adding it to boiling water, add it in normal water and slowly raise the water temperature. The slower the rise, the sweeter it becomes.


Wednesday, August 07, 2013

The fishy life of Ocean fish.

The belief that fish is good for us is one important reason for the growing consumption of fish in the world. Fish are a rich source of Omega-3 fatty acids, which our body cannot make efficiently. Omega-3 fatty acids are essential for the development of brain and the retina and an abundance of it appears to maintain the health of our central nervous system. Other than this, Omega-3 is also suppose to have anti-inflammatory properties. (Human body converts Omega-3 fatty acids to eicosanoids, which signals the immune system to calm down after it has completed its job). This and many other properties of Omega-3 fatty acids, ensures that a moderate a regular consumption of ocean fish good for us. It so happens that just like humans even fish do not make Omega-3 fatty acids. They obtain it directly or indirectly from tiny oceanic plants called phytoplanktons. Hence farmed fish and fresh water fish, have negligible quantity of Omega-3’s in them, since they do not have access to the oceanic plants. Ergo, your only reliable source of Omega-3 is wild ocean fish. Unfortunately, most of the fish in our polluted waters have become a sponge for industrial and biological toxins. Chemicals from pesticides, industries and other human activities bio-accumulate in the fish. Dioxins, polychlorinated biphenyl’s mercury, lead, cadmium and copper are found in sea fish today. These pollutants, cause liver damage, cancer and affect the foetus in pregnant women. Hence today children and pregnant women are advised not to eat any fish, particularly swordfish, shark, tilefish and king mackerel’s among others. The fish least likely to accumulate toxins are small, short-lived fish from open ocean like Pacific Salmon, common mackerel, sardines and catfish.

When you arrive at a beach or ocean coast, after a prolonged period, do you remember smelling the ocean aroma? A smell that reminds you of your proximity to the sea. This aroma is because of compounds called bromophenols and are synthesised by algae and some primitive creatures from bromine. Bromine is abundant is sea water and bromophenols are propelled into the seacoast air by wave action. Fish also accumulate them, and thus remind us of the sea air. Freshly caught fish has smell of crushed leaves! The large, aroma-less, fatty molecules of both fish and leaves are broken down by enzymes called lipoxygenases into small aromatic fragments. These fragments have a green-leaf like aroma and some freshwater fish produce fragments that smell like melons and cucumbers.

Tuesday, August 06, 2013

Good Barbecue Ideas

In previous posts, I have described how cruelly farm animals are treated on their way to your dinner plate. Despite this, I don’t expect you to give up eating flesh, because of a few posts of mine (It took me three years). In today’s post, I am going to tell you how you can safely grill meat- The benevolent blogger that I am. Scientist today have indentified three families of chemicals created during meat preparation that damage DNA and they suspect may cause cancer in mammals, especially of the large intestine.
1. Polycyclic Aromatic Hydrocarbons (PAH): These are created when any organic material, including wood and fat is heated until it begins to burn. Barbecuing, over a smoky wood fire therefore deposits PAH’s from the wood on meat. Additionally when fat from meat falls over wood, charcoal or red-hot grill and begins to burn, or if the fat ignites on the meat itself (a common occurrence when you barbecue) PAH’s are created. You can reduce the amount of PAH’s on your barbecue by using coal instead of wood or charcoal. By leaving the grill uncovered so that soot and vapours can disperse and by avoiding fat flareups.
2. Heterocyclic Amines (HCA’s): These are formed at high temperature when meat components like creatine and creatinine react with amino acids. HCA’s levels are highest on the surface of the meat, where the temperature is highest. They are also found in large quantities in meats that are grilled, broiled or well fired. To reduce carcinogenic effects of HCA, aim for rare or medium cooked meat. Vegetables and fruits bind HCA’s in the digestive tract and reduce the damage caused by them. So have lots of veggies with you meat.
3.Nitrosamine: These are among the most powerful DNA-damaging chemicals. Nitrosamines are formed when nitrogen-containing groups on amino acids react with nitrite that is used in salt-cured meat. The reaction can take place both in the frying pan and well as in the gut. You can reduce Nitrosamine formation, by avoiding salt cured meat, especially, which uses saltpetre ex. Sausages, hams, bacon and corned beef. The most unsafe place to buy meat is United States, Canada and North America in general. Europe is probably the best among all nations and Australia, New Zealand and Japan fall somewhere in between. In rest of the countries, lack of legislation on meat safety makes buying meat more of a game of chance. 

I rate US poorly for its meat quality because of the following reasons. 1. Animals are cramped, without access to outdoors and natural light and stressed up all their lives, unlike in Europe or New Zealand. 2. Hormones, which are outlawed in Europe are still used in US 3. Animal feed is laced with antibiotics, which has encouraged evolution of antibiotic resistant campylobacter and salmonella causing disease in US consumers. Europe has strict restriction on using these antibiotics. 

Monday, August 05, 2013

Virus to treat bacteria.

In 1917, a Canadian-born physician, Felix d’Herelle was investigating an outbreak of dysentery among the French soldiers, fighting the First World War. The microbes were killing the French soldiers in droves, not only invading their torn flesh, but also their food and water. As part of the analysis, Herelle passed the stool of the soldiers through a filter. The filters pores were so fine, that not even the bacteria that caused the dysentery, known as ‘Shigella’ could slip through. Herelle then took the filtered fluid and mixed it with a fresh sample of Shigella bacteria and spread it in a petri dish.

As the Shigella began to grow, Herelle noticed strange clear spots starting to form in their colonies. Herelle concluded that they were viruses, which were infecting and killing bacteria. Herelle, named these viruses, bacteriophages, meaning eaters of bacteria. Today they are known as phages for short. Scientists were aware of viruses that attacked human, plants and animals. But the concept of bacteria-infecting viruses was so strange and so new that some scientists refused to accept it. The debate on the subject raged for years. Only in 1940’s, when the electron microscope was invented and scientist could visually see the lunar lander like phages, was their presence accepted. On his part though, Herelle did not wait for the debate over phages to end before he began to use them to cure the patients. Herelle noticed that as the levels of phages in the stool climbed, the soldiers started to recover from dysentery. Herelle realised that phages were actually killing the bacteria and if he gave his patients extra phages, he could eliminate diseases faster. To ensure that the phages themselves were safe, Herelle swallowed some and injected some phages into his skin and suffered no ill effects. His phage therapy helped people recover from dysentery, cholera and bubonic plague. Heller developed phage-based drugs that were sold by the company that’s now known as L’Oreal, to treat skin wounds and cure intestinal infections. By 1940’s the phage craze had come to an end, the idea of using live viruses as medicine had made many doctors uneasy. Also in 1930’s antibiotics were discovered, which cured infections faster and unlike phage, were just artificial chemicals. Herelle died in 1949, but his dream of phage therapy was kept alive by a Soviet Institute named Eliava Institute in Tbilisi (presently in Georgia). With antibiotic resistant bacteria on the loose, advocates of phage therapy are back in news. Advocates of phage therapy contend that as bacteria evolve to resist new drugs, the phages too can evolve to fight back. Now 90 years after Herelle first encountered bacteriophages, these viruses may finally be ready to become part of modern medicine.