Tag: medicine

Posted in Psychology & Medicine

Sneeze

Posted on by Jinavie

A sneeze is caused by the body trying to remove something that is irritating the nasal cavity. To do this, it contracts many respiratory muscles instantly to create a powerful expiration. This produces a gush of air and the foreign material at a speed of over 150km/h, which can spread saliva and mucus at a range of over 2m. Therefore, not putting your hand over your mouth during a sneeze is an easy way to spread infections like the common cold.

An interesting fact is that one cannot open their eyes during a sneeze. This is not because of the urban legend that the eyeballs pop out if the eyes are open when sneezing, but part of the reflex and powerful contraction of muscles. Also, pinching between the two nostrils very hard can stop a sneeze reflex successfully.
Lastly, although sneezing is usually due to breathing in an irritant, some people have what is known as a photic sneeze reflex (also called the ACHOO syndrome), wherein they sneeze when stare into bright light such as the sun.

Posted in Psychology & Medicine

Babinski Reflex

Posted on by Jinavie

Normally when you tickle or stroke the sole of your feet, the toes flex inwards. However, when a newborn’s feet are tickled or stroked, the toes spread outwards. This is known as the Babinski reflex, or Babinski sign. It is a primitive reflex that disappears before 12 months of age.
If this reflex is seen after that, including adults, it is a sign there is something wrong with the nervous system, especially the brainstem or the spinal cord.

A primitive reflex is one shown by newborns but disappears gradually as they develop. These include reflexes such as the walking reflex, swimming reflex and crawling reflex that shows actions that they have not yet learnt, or the rooting reflex and sucking reflex that ensures the baby’s survival.

Posted in History & Literature

3000 A.D.

Posted on by Jinavie

How will the world change over the next millennium? Everything will change: from lifestyle and culture, to international politics and economics. This makes the posited question extremely interesting.

As science will continue to advance rapidly, technology that can only be dreamed of by modern man will become commonplace in the future. For example, computers will become essential tools such as pen and paper, or possibly become obsolete like the typewriter. Human beings will rely more and more on machines, which may lead to human-machine interfaces and cyborgs, or simply robots becoming common household appliances. Space travel will become as common as air travel, and humanity may even begin to colonise other planets or moons.
As this field can flow in completely unpredictable directions, it is extremely hard to know what will come. One thing is for sure: there is infinite potential in science for at least the next thousand years.

The continuing evolution of medicine and advanced hygiene policies will increase the lifespan of the world. This will bring upon the aging of the population, a “disease” that already plagues some developed nations. Governments may even respond with extreme solutions such as setting an age limit (or killing the elderly to change the demographics), but the more likely option is lengthening the period of youth or reversing aging to prevent the phenomenon of an elderly population.

Socially, the internet will allow for a ubiquitous society, bringing together the entire world. However, the internet is a double-edged sword that may improve interpersonal relationships, but also cause people to become antisocial and communicate only via electronic screens. Unfortunately, it is unlikely the gap between the rich and poor will be filled. The reason being, people’s basic instinct to take from others to improve their own life means that there will always be those who are rich and those who are poor.

In mankind’s history, there have been only a few empires that have survived over a millennium. Even the United States of America that currently is the leading nation is showing signs of deterioration, and China will instead rise to the top over the next few hundred years. But no one knows who will be the strongest power in the year 3000, as even a (currently) weak nation may suddenly strike and claim the throne.
For example, the Roman empire 2000 years ago, the Mongol empire 1000 years ago, and the Ottoman empire 200 years ago have all fallen and have only become pages in history books now.

Even after two vicious world wars, future nations may ignore history’s teachings and cause a third world war, which could involve the use of nuclear weapons. In this case, the world will definitely be unrecognisable compared to now. 
Alternatively, history may take a peaceful course where the concept of “nations” crumble and instead a united world is formed.

An even more interesting thought is “How will future people see us?”. As we mock the unsanitary conditions, violent history and underdeveloped science of the past, the future may laugh at concepts such as paternalism and communism, or even our fashion of jeans and shirts.
On the other hand, it is possible that works such as Harry Potter or House MD will be seen as classics and become the future Shakespearean plays.

As seen from this, the possibilities for the future are endless, and pondering the different futures sometimes bring light to ways to improve the present.

Posted in Science & Nature

Making A Human

Posted on by Jinavie

What ingredients are needed to make a human being?

  • Water 35L
  • Carbon 20kg
  • Ammonia 4L
  • Lime 1.5kg
  • Phosphorous 800g
  • Salt 250g
  • Niter 100g
  • Sulfur 80g
  • Fluorine 7.5g
  • Iron 5g
  • Silicon 3g
  • And traces of 15 other elements such as zinc, copper, magnesium etcetera.

To buy all of the above ingredients costs less than $5 USD.

Posted in Psychology & Medicine

Love And Heartbeats

Posted on by Jinavie

A thumping heart is often quoted as the first sign of love – a way of your body telling you that the girl or boy in front of you is what you desire.
But does love come first or does your heartbeat come first?

Although most people believe that their heart is beating faster because they’re in love, science proves that it is in fact the opposite.
An experiment was designed where male subjects were asked to answer a questionnaire given out by an attractive woman. One group had to cross a very long suspension bridge first, the control group had to cross the same distance on flat, solid ground. It was found that men from the first group were more likely to complete the questionnaire, give answers that were more romantic and sexual, and even call the survey girl afterwards.

Similarly, a group of men were shown four women while being connected to headphones that played back their own heart sounds. They were then asked to rate which girl was the most attractive.
After the experiment, it was found that the third girl received a landslide win, despite the different tastes of each man in the group. When asked, the subjects all replied that they heard their heart speeding up, thus believed that they found her the most attractive.
The twist was, when the third girl was shown, the audio was changed from the subject’s heartbeat to a pre-recorded heartbeat that beat faster than normal. Therefore, the men were fooled into thinking that the girl was more attractive by “increasing” their heart rate. This phenomenon was found in women also.

The answer to the question is that dopamine and serotonin, neurotransmitters secreted when a person is in love, also has the effect of increasing one’s heart rate. The brain therefore can misinterpret an increased heart rate as the effect of love through false association.
This effect is quite well known in dating tips as people are encouraged to go to places that invoke fear or excitement, such as an amusement park, horror movie, or high place to gain the best response from the opposite sex.
Ergo, science does play a role in love and just like anything else, it can be easily manipulated.

Posted in Psychology & Medicine

Hiccup

Posted on by Jinavie

A hiccup is a common phenomenon that almost everyone experiences some time in life. The exact mechanisms are still not well known, but it is likely caused by an irritation of the phrenic nerve, which supplies the diaphragm, causing it to spasm and interrupt normal breathing.

This can be a very debilitating condition, and such there are hundreds of “remedies”, such as drinking cold water, holding your breath or giving the person a scare. However, these are often ineffective in taking away the ailment. 

One thing you can try is pulling your tongue. Although it may sound like a crazy treatment, it stimulates the vagus nerve which can stop a hiccup. However, note that this may be ineffective in many cases as well.

In some cultures, it is said that hiccups are brought on by eating something one stole off another person, or if others are talking about you in a bad manner.
The world record for the longest attack of hiccups is held by Charles Osborne, who had it for 68 years.

Posted in Philosophy

Occam’s Razor

Posted on by Jinavie

Occam’s razor is a philosophical concept that dictates that all other things being equal, the simplest solution is the best. It is useful in many situations, especially the sciences, where it allows one to find an answer without being distracted by the numerous variables.

In medicine, Occam’s razor is extremely useful in differential diagnosis where a doctor may easily prioritise the possible diagnoses and save precious time. Dr Greg House in House MD shows demonstrates just this.

In physics, models showing movement of objects for calculation of force required ignores real factors such as friction or centrifugal force to simplify the situation, showing only the forces being observed. This type of modelling is used in many subjects, where only factors being observed are taken into consideration to find a correlation, or some form of desired truth. 

Although some may suggest that this method does not give the “truth” as vital information may be cut out in the process, it can also be argued that one cannot see the truth unless the “distractions” are removed. This is the fundamental basis of the Occam’s razor, where complexities are “shaved” away until truth is left. A quote by the musician Daniel Jacobs, “The truth of simplicity is camouflaged by the complexity of lies just as a tangle of lies will mask the simplicity of truth,” also supports this idea.

Posted in Science & Nature

Parthenogenesis

Posted on by Jinavie

It is often believed that for complex organisms such as animals, sexual reproduction is a must to produce offspring. Asexual reproduction is common in bacteria and (some) plants, but even tiny beings such as insects use sexual reproduction to produce a mass of variable offspring. 

However, it has been found that despite having two clear sexes – male and female – there are cases where a certain species is able to reproduce without the need of sexual intercourse. In these cases, the female’s eggs spontaneously divides to form a new offspring without being fertilised by a sperm. Furthermore, sometimes the egg either fuses with another egg or undergo several genetic mixing and mutation to produce some variety in genetic pool, thus avoiding the issue of asexual reproduction (where the entire population can be wiped out by a single disease due to identical genetic makeup). This is known as parthenogenesis, and it has been documented in many insects, fish, reptiles and even birds. 

Obviously, as there is no donation of a Y chromosome, every offspring born from parthenogenesis is female. Because of this, some species such as the New Mexico whiptail, a lizard that is capable of both sexual reproduction and parthenogenesis, the population has completely rid itself of males, making it a completely female species. Curiously, they still engage in “mock sex”, giving them the nickname “lesbian lizards”.

Although parthenogenesis has never been documented in mammals in nature, it has been induced artificially in mice, rabbits and monkeys. However, they all developed severe developmental issues due to the numerous mutations in the egg required for parthenogenesis. 
But if in the future, human parthenogenesis is perfected, it is possible that humanity too could end up as an all-female society.

Posted in Psychology & Medicine

Vertex

Posted on by Jinavie

The vertex, also known as the crown of the head, is the uppermost point on the human body on the top of the head. It is the part of the body that comes out first (usually) during childbirth.

There are some interesting properties regarding this anatomic location.

Firstly, if one places a cellphone on top of their head, they cannot feel the vibration when they receive a call or text message. Almost every other part of the body can feel the vibration, but not the vertex. This is because the top of the skull is not covered by any muscles, which have receptors that sense vibrations. Ergo, no vibrations can be felt.

Secondly, when one places their hand on top of their head, they experience a sudden drop in muscle strength. This applies to the whole body and can be seen through basic activities such as lifting weights or even through arm-wrestling. The degree of weakness can be up to 10~15% of the muscle’s normal strength. 

The reason for this is slightly more complicated. The nervous system remembers trauma and responds to it, such as childbirth where almost everyone (assuming they were born through vertex presentation, the most common) experiences trauma on the top of the head. For example, as labour is quite an intensive procedure, significant pressure is placed on top of the baby’s head as it tries to push out.
Because of this, when pressure or electric signals are exerted on the vertex, the nervous system responds negatively, remembering the trauma from childbirth, and “weakens” throughout the body. This results in decreased force exertion by muscles. The same effect can be achieved when a cellphone is placed on top of the head, as it emits electric signals.

Lastly, the top of the head is not sealed until a few months after birth. This makes a baby’s skull very malleable, and two fontanels, which are gaps between pieces of the skull, remain open for that time. This is seen as “soft spots” on the head which pulsates as there is no bone beneath it.