Moon doesn't always rise in the evening!

Most of us think Moon does the night-duty in an office where Sun does the day-duty. Majority of our literature pictures Moon like that; someone who rises in the evening after sunset and sets when Sun rises. But the fact remains, only once in a month our Moon does like that. If you are a good observer without much knowledge in astronomy, you may know that the fact I said is right. But still, you don't know why it is like that. This time we will talk about the Moon's drama up there in the sky.

As you all know, the shape of Moon we see is not always the same. It waxes and wanes in size and shape (വൃദ്ധി-ക്ഷയങ്ങള്‍) called the phases of Moon. Most of us think that this is due to Earth's shadow falling on Moon, don't we? But thing is NOT like that. Earth's shadow has nothing to do with this. It is because, as Moon goes around Earth, from here we see it from different angles on different days. I can make it more clear with a picture below.

Here the situations of Moon being at different positions around Earth is shown. Sunlight will illuminate Moon as it does to Earth. As Moon is a sphere, only half of it will be illuminated at a time (Exactly this is how half of Earth experience day and other half experience night at the same time. When at one side of Earth it is noon, the opposite side of it will have a midnight as shown in picture). As Moon goes once around Earth in every 27 (approx) days, its position around Earth with respect to the Sun rays will be different on every day of this 27 days period. Just take a little time to look at the picture. Seeing from Earth, when Moon is in the direction where sunlight comes from, the part of Moon illuminated by Sun is on the back side and so we cannot see Moon at all. In other words, we are seeing the 'night' in Moon. That day is what we call New Moon. Now consider when the position of Moon is opposite to the direction of Sun, the whole of illuminated Moon is visible to us, giving us a full moon day. (From picture you can also make out that a full moon comes right ahead on sky at midnight) On all other days we can see only a part of illuminated surface of Moon which becomes larger when we go from new moon day to a full moon day. In short it is not the shadow of Earth but the shadow of Moon itself, that causes the phases.
Now let us come to the point in title. First of all, we have to remember that the rise and set of any object on sky is due to the rotation of Earth around its on axis. As we have seen, on a new moon day Sun and Moon are on the same direction and so they rise together. (Yes, Sunrise and Moonrise are together!) But on a full moon day, they are on opposite positions and so Moonrise and Sunset happens together. That means Moon can rise at any time. On a particular day it will rise 5o minutes later it rose the previous day due to its motion in its orbit around Earth.

A shock-relieving talk on Shock Treatment

       Majority of us keep a horrifying picture about Shock treatment used for the cure of mental illnesses. The bad credit goes mainly to the movies that mislead us and give a feeling that it is some kind of torture or punishment given to the most violent of mental patients.
       So, here we are going to have a talk on the same Shock Treatment that I hope will untether you off some misconceptions.
       'Shock treatment' is just a nickname of this method. Psychiatrists call it as 'Electroconvulsive Therapy' or simply ECT. It will be interesting to know that ECT is the first discovered meaningful treatment method in psychiatry (for movies have always picturized it as a last resort). For the sake of a little history, there was no meaningful treatment for mental illness around just 70 years ago. Von Meduna, a Hungarian psychiatrist, observed that epilepsy and schizophrenia rarely coexist. Even if they did, the seizures (or fits, loosely speaking, the sudden movement of muscles) associated with epilepsy reduced the severity of psychosis. This lead him to develop a treatment for psychosis: to induce seizures artificially using drugs. But use of drugs had many limitations because there was no considerable control over the way seizures occurred. Thereafter, Carletti and Bini, two Italian psychiatrists discovered that electricity can be used to induce seizures in a much controllable way. In 1938, the first experiment of ECT was done on humans, to be found a great success.

A psychotron used to control ECT

       ECT is not at all a cruel treatment. Before applying ECT to a patient, he is always undergone a 'fitness test' including EEG, and X-ray. To those who think it is a torture, ECT is never conducted on a conscious patient but is always given after an anesthesia. That means you don't feel any pain at all. Also drugs are given to prevent very violent movement of muscles during seizures. While doing all these pre-ECT steps, the patient is allowed to breath pure oxygen (a process called hyperventillation). The amount of current passed  is only around 0.5-0.8 ampere and that is for less than 4 seconds, using an apparatus called psychotron. This current never reaches the brain. It just flows through the scalp tissues and so there is no 'struck by lightning' type effects as we see in movies. This current can stimulate brain activity. It is this stimulated brain activity and NOT the electrical stimulus that causes the sudden muscular movements. When the effect of anesthesia wears off, the patient would wake up comfortably.
ECT produce recovery faster than drugs. It is also used in drug-resistant subjects (that is if patient does not respond to medicine) It is not necessarily meant for only the very violent and uncooperative patients (for such patients ECT will be the only way) but is also prescribed for very depressed patients. Psychiatrists say that patients who have received ECT find it less frightening than going to a dentist!
       One more interesting fact: despite being a 70 year old and globally used method, no one knows exactly how ECT works in human body!

Polysomnography: Measuring sleep!

Today let us talk about another interesting term, Polysomnography. Those who already know that the Latin word 'somnus' means sleep, can guess what polysomnography deals with. Yes, it is a standard procedure to evaluate sleep, mainly for the cure of sleep disorders.

Well, when I say 'measuring sleep' what actually are we measuring? Polysomnography is a multi-parametric test (means it measures different parameters connected to the sleep activity, lest you are frightened by the term multi-parametric) Mainly there are three parts in your body that responds directly to your sleep; brain, eyes and muscles. The study of activity in these three parts constitute the core of polysomnography. Measurements are carried out by placing electrodes on specific parts of the body and measuring the voltage change associated with the corresponding activity.

Now let us have a close look at the core parameters:

Brain activity:

It is studied by the ordinary EEG (Electro Encephalography) technique. It is based on measuring the bioelectric aactivity of brain by placing electrodes on the scalp of the person in sleep. EEG will look like a polygrah, the one you see in a seismogram record of earth quake. Like a random scribble made by a pen. But by looking at EEG, the researcher can understand the various stages of the person's sleep.

Eye movements:

It is studied by a technique called Electro Oculography (EOG). It is based on a rarely known fact that the front part of our eye called Cornea is electrically positive with respect to its hind part Retina. This voltage will obviously change when eye moves left, right, up or down. EOG is based on the measurement of this voltage, thereby giving an idea about the eye-movements.

Muscle activity:

This is studied by a technique called Electro Myogram (EMG). The movements of our muscles are a result of rapid electrical activity within the muscle tissues. EMG measures the voltage change associated with it. In polysomnography, EMG electrodes are usually placed over the chin muscles.

A sample polysomnogram

Along with these many similar activities in the body can also be studied for a very detailed analysis, three of them being  breathing, heart rate and contraction of leg muscles.

QWERTY Keyboard: Why is it the way it is?

       If you are reading this, surely you have a keyboard in your front. I assume you are using a QWERTY keyboard, which is the most common layout of keyboard.(If you don't know what QWERTY means, it is the name of the way in which keys are arranged in your keyboard. The name obviously comes from the first six letters of the top row of alphabets in your keyboard.)
       Now my question is, do you know why keys are arranged in some seemingly random way rather than in an order? I had asked this question myself and to others, and frankly the answer I could end up in was 'this way makes typing more fast and efficient'. But how? I got many explanations from many and even from myself (rather fit-to-reality type explanations!) all of them being supportive to the making-typing-faster concept.
       But actually, fact is just the reverse. QWERTY layout was invented to make people type slowly, and not fast! Yes it is. This layout was designed by Christopher Sholes in 1874 as part of his design of the first typewriter for Remington & Sons. Obviously, the first typewriter was purely a mechanical device in which pressing of a key would cause a bar to strike against the paper through an inked ribbon. In that machine there was a problem: if you type too fast the bars corresponding to different keys would collide with each other and thereby would jam the machine. Sholes found out an easy remedy for this. He just placed the most commonly used letters in hard to reach positions! And there it was, the QWERTY layout. The Remington typewriters became so popular that even after the invention of electronic typewriters, the Sholes' layout had to be followed as such because people had got used to it. That is how this layout became a universally accepted standard for keyboard.

@ at 'Did You Know' !

     @ is one of the most common symbols used nowadays. @ became so popular after the invention of e-mail. But how many of us know the standard name of that symbol? Alas! I was sad to know that @ symbol has no standard name! You may be calling it as 'at symbol' (so do I). But there are dozens of other names for @ that reflects similes for the symbol.  Examples are apestaart (Dutch for "monkey's tail"), snabel (Danish for "elephant's trunk"), kissanhnta (Finnish for "cat's tail"), klammeraffe (German for "hanging monkey") etc.
     Before it became a standard symbol in e-mail addresses, @ was used as 'at the rate' for referring to cost or weight of things (e.g. Books @ $5 each). It seems the actual origin of the symbol is still unknown. Some evidences show that before printing presses were invented people who made copies of books used '@' as a short form of 'at'. Another story tells that @ was used as an abbreviation of 'amphora', an old unit of measurement. Anyway solid records are there to show that the symbol @ was used even in 14th century.