PANCH RATHAS OR THE FIVE RATHAS

The five Rathas is a set of magnificent monolithic rock temples. Panch is a Hindi world which means ‘Five’. These fine rock temples are located in a sandy compound. These five Rathas are the perfect examples of the evolution of Dravidian style architecture. There are built in the shaper of pagodas and they look similar to that of the Buddhist shrines and monasteries. Rathas in English means carrots. There chariots are constructed with Towers, The cars of gods, multipillared halls, and sculptured walls which are chissled out minutely. The Rathas have an association to the great epic Mahabharata which describes the heroes of Mahabharata with their wife Draupadi which is termed as pancha pandava rathas. The five rathas are (i) Draupadi’s Ratha, (ii) Arjuna’s Rath, (iii) Nakul – Sahadev’s Rath, (iv) Bhima Rath and (v) Dharamraja Yudhistar’s Rath.

DRAUPADI’S RATH

This is located at the entrance gate, which is spectacular and simple, shaped like a hut and is dedicated to goddess Durga. Female door – keepers stand on the either ride of the Rath, one holding a bow and another, a sword. At the eastern wall a bas-relief stands portraying Goddess Durga standing on lotus and two worshippers at here feet offering flowers and one of the person’s head respectively. Energy other walls have the figure of the great goddess, and at the front of the temple is a Lion’s figure, which is the celestial vehicle to the Goddess.

ARJUNA’S RATH

The next Rath is the Arjuna’s Rath. This one is dedicated to Lord Shiva. This has a small portico and carved pillar stones. Inside the shrine there are no inscriptions or figures whereas on the outer walls. There are carvings of gods and humans. A panel on the4 northern wall is carved with two door-keepers. Beautiful carvings of Lord Vishnu and a Garuda on One panel and the other panel with a couple. The eastern wall is carved with a double Dwarka-Palaks, in the middle wall the portrait of Lord Indra riding an elephant, a log standing of the left with has disciples and two beautiful women are perfectly chissled out. These beautiful carvings hare been praised by many poets. There is also a figure of Nandi bull – which is still left unfinished.

NAKUL – SAHADEV’S RATH

In front of Arjuna’s Rath is the Nakula – Sahadev Rath. This is a double decored building, dedicated to Lord Indra – the God of Rain. As in Greek and Roman mythologies, where there are different gods for various aspects and qualified, the Indian mythologies too lane assigned specific gods for different aspects. There is some proof depicting this Ratha to which might have been dedicated to Subramanya associated with elephants. The elephants shaped sculptures face towards the sea. One who eaters the Panch Rathas, can visualize the back portion of the elephants and it named as Gajaprishthakara which means elephant’s back side. The elephant sculptures are huge and are highlights of the Panch Raths.

BHIMA RATH

This Ratha is faced towards west and this is laid third of the Rathas. The shrine is gorgeous as it measures 42 ft in length, 24ft in width and 25ft in height. The pillars are lion carved whereas the other parts are plain. This Ratha too is an incomplete one. In the epic Mahabharata Bhima the huge guy is bulky and strong he is fond of eating all the time.

DHARMARAJA YUDHISTAR’S RATH

Of all the five Rathas, this last one stands huge. It is named after the eldest of the pandavas. Innovative and well carved designs can be seen in this Rath. This resembles the Arjuna’s Rath and it is a perfect example to the later built South Indian Temples. This Rath is also dedicated to Lord Shiva like that of Arjuna’s Rath. The ground floor is in complete. Above the ground floor stands minutely designed double floor. The peculiarity in this monumental construction is that there is no stair route from the ground floor to the first floor, but, there in stairs from the first floor to the second floor. There are eight panels in the ground floor. One panel is carved with the portrait of the kind and the rest with gods and goddesses. On one particular wall the figure of shiva is named ‘Ardhanariswarar’ which is the mixture of Shiva and Shakti. This is very attractive as one can find the manly structure and the luring female charm. Other portrayals show lord shiva as ‘Bhikshatana’ – meaning cosmic designer and the god of death.

Twenty two carves are found on the first floor. There is no central pasteurization in the first floor. The portrait of lord Krishna dancing on top of the fierce kaliya snake is depicted on the southern wall. Lord Vishnu’s portrayal is found on the Northern wall. Carving of a bearded ascetic holding a bell in his hands, a devotee with a tuft, holding a flower basket, a temple attendant with bunch of keys and carrying offering to god are marvelously inscribed. The second floor is well carved. Figures of Dakshinamurthy, somaskanda, the sun the moon and other worshippers all found in this floor.

THE GANESH RATH

The only completed sculpture of the fine Rathas is the Ganesh Rath. This lies west to the Bhim Rath and it resembles the Arjuna Penance. It was earlier dedicated to lord shiva and now it is a shrine of Ganesha. There was a lingam structure earlier and now an idol of lord Ganesha has been replaced the pallavas did not stop with there fine Raths but they went on to build more sculptures of them four are found lying on the outskirts of mahabalipuram. Two Raths which lie side by side on the way to Tirukkalakundram are named as Pidari Rathas. To the south of these two Rathas lies the Valayankuttai Rath and the fourth one which lies opposite to the Mahishasura Mardini Mandap is nameless.

Earthquakes

Why do earthquakes form?

Forces causing earthquakes were not close to the earthquake source but very distant. these distant forces cause a gradual build up of stress in the earth over tens or hundreds or thousands of years, slowly distorting the earth underneath our feet. Vibrations called seismic waves are generated and travel both through the earth and along its surface. Eventually, a pre-existing weakness in the earth--called a fault or a fault zone--can not resist the strain any longer. This is something like pulling a rubber band gradually until the band snaps. This theory is known as the "elastic rebound theory."

Intraplate earthquakes are not as frequent or as large as those along plate boundaries. The largest intraplate earthquakes are about 100 times smaller than the largest interplate earthquakes.

Intraplate earthquakes tend to occur in soft, weak areas of plate interiors. Scientists believe intraplate quakes may be caused by strains put on plate interiors by changes of temperature or pressure in the rock. Or the source of the strain may be a long distance away, at a plate boundary. These strains may produce quakes along normal, reverse, or strike-slip faults

The earth can be divided into four main layers: the solid inner core, the liquid outer core, the mantle, and the crust. An earthquake is caused by a sudden rupture in a fault. A fault is the fracture within the rocky mass inside the earth's crust. The depth and length of faults vary greatly.

Scientists have developed a theory, called plate tectonics, that explains why most earthquakes occur. According to this theory, Earth's outer shell consists of about 10 large, rigid plates and about 20 smaller ones. Each plate consists of a section of Earth's crust and a portion of the mantle, the thick layer of hot rock below the crust. Scientists call this layer of crust and upper mantle the lithosphere. The plates move slowly and continuously on the asthenosphere, a layer of hot, soft rock in the mantle. As the plates move, they collide, move apart, or slide past one another.

The movement of the plates strains the rock at and near plate boundaries and produces zones of faults around these boundaries. Along segments of some faults, the rock becomes locked in place and cannot slide as the plates move. Stress builds up in the rock on both sides of the fault and causes the rock to break and shift in an earthquake.

The world's deepest earthquakes occur in subduction zones down to a depth of about 450 miles (700 kilometers). Below that depth, the rock is too warm and soft to break suddenly and cause earthquakes.

How do earthquakes form?

Stress in the earth's outer layer cause a pushing effect against the sides of the fault. Due to this motion, rocks slip or collide against each other releasing energy. This released energy travels in waves through the earth's crust and causes the shaking that we feel during an earthquake.

Under the surface of the earth, the two sides of a fault are constantly moving, relative to one another. This movement is known as a fault slip. The movement of these two sides is not smooth and is accompanied by a gradual build-up of elastic strain energy within the rocks along the fault.

Eventually, the strain along the fault becomes too much.The fault then ruptures with a sudden movement releasing all the energy it has built up. This energy is released in the form of vibrations called 'seismic waves'.

These waves travel along the surface and through the earth at varying speeds depending on the material through which they move. It is actually these seismic waves that cause most of the destructive effects, which we associate with earthquakes.

The location on a fault where the slip first occurs is called the hypocentre, whereas the position directly above it on the ground surface is called the epicentre.

When these seismic waves reach the surface of the earth, they give rise to strong ground motion causing building and other man-made structures to shake or collapse or develop cracks and fissures.

Earthquakes can also cause landslides, sudden eruptions as in the case of a hot lava flow from a volcano or giant waves called tsunamis. Sometimes new land mass are also formed.

Where do earthquakes occur?

Where Are Earthquakes Likely to Occur?

Within areas of the crust are fractures, known as faults, along which two crustal blocks have slipped or moved against each other. One block may move up while the other moves down, or one may move horizontally in one direction and the other in the opposite direction. earthquakes occur repeatedly at faults, which are zones of weakness in the earth's crust.

How Deep Do Earthquakes Occur in the World?

Earthquakes occur In the crust or upper mantle which ranges from the surface to about 800 kilometers deep (about 500 miles).

95% of all the world's earthquakes occur at active plate boundaries . California, Alaska, Japan, South America, and the Philippines are all on plate boundaries. Only 5% are in areas of the plates far away from the boundaries.

Earthquakes usually occur where two of the earth's tectonic plates meet. These boundary regions, therefore, are particularly prone to earthquakes (and also to volcanic eruptions). The edges of the giant Pacific plate, which lies beneath the Pacific Ocean, form a particularly intense ring of tectonic activity, known as the "ring of fire." This activity causes frequent earthquakes along the west coast of North America and in Chile, Alaska, and Japan, and is also responsible for volcanic eruptions in the northwest United States, the Andes Mountains, and the Philippines.

Types of earthquakes

Interplate earthquakes occur along the three types of plate boundaries: (1) mid-ocean spreading ridges, (2) subduction zones, and (3) transform faults.

How are earthquakes measured?

A seismometer is an instrument that senses the earth's motion; a seismograph combines a seismometer with recording equipment to obtain a permanent record of the motion. From this record scientists can calculate how much energy was released in an earthquake, which is one way to decide its magnitude. Calculations are made from several different seismograms, both close to and far from an earthquake source to determine its magnitude. Calculations from various seismic stations and seismographs should give the same magnitude, with only one magnitude for any given earthquake.

To determine the strength and location of earthquakes, scientists use a recording instrument known as a seismograph. A seismograph is equipped with sensors called seismometers that can detect ground motions caused by seismic waves from both near and distant earthquakes. Some seismometers are capable of detecting ground motion as small as 1 billionth of a meter, or about 40 billionth of an inch.


A seismograph produces wavy lines that reflect the size of seismic waves passing beneath it. The record of the wave, called a seismogram, is imprinted on paper, film, or recording tape or is stored and displayed by computers

The Richter scale is a standard scale used to compare earthquakes. It is a logarithmic scale, meaning that the numbers on the scale measure factors of 10. So, for example, an earthquake that measures 4.0 on the Richter scale is 10 times larger than one that measures 3.0. On the Richter scale, anything below 2.0 is undetectable to a normal person and is called a microquake. Microquakes occur constantly. Moderate earthquakes measure less than 6.0 or so on the Richter scale. Earthquakes measuring more than 6.0 can cause significant damage. The maximum quake rating ever measured is about 8.9.

The Modified Mercalli Intensity Scale uses Roman Numerals from I to XII to describe different earthquake effects is commonly used.

Safety first for earthquakes

Can Earthquakes Be Prevented?

There is no known way to prevent earthquakes, but it is possible to lessen the impact. The amount of devastation from an earthquake can be greatly diminished by building structures using earthquake resistant design, making the interiors of buildings safe from falling objects, and educating people about earthquake safety.

China cabinet (Should be attached to wall studs)

Tall knickknack shelves (Should be attached to wall studs)

Bookshelves (Should be attached to wall studs)

Heavy hanging plant over a place where people sit (should be light, unbreakable pot and make sure all plants hang from ceiling studs)

A mirror on the wall (Make sure it is well fastened to the wall)

Heavy objects on wall shelves (should be moved to bottom shelves or secured)

Unsecured TV on a rolling cart (Make sure cart wheels are blocked so TV can’t roll)

Bed by a big window (Bed should be moved away)

Heavy picture above a bed (Bed or picture should be moved)

A hanging light above a bed (Light should be secured with extra wire or chain, or the bed should be moved.)

Cabinet doors not fastened to stay closed (Install latches)

Unattached water heater (Attach water heater to the wall studs)

Gas stove with rigid feed line (Replace gas line with flexible connectors)

Heavy wall clock (Attach to wall studs)

Chimney (Brace outside chimney to the house)

House not bolted to the foundation. (Foundation should be bolted)

The most important thing to remember during an earthquake is to DROP, COVER and HOLD ON. So remember to DROP to the floor and get under something for COVER and HOLD ON during the shaking.

Many people are injured by falling debris just outside buildings. Usually it's better to stay inside if you are already inside, and to stay outside if you are already outside. Inside, try taking cover underneath something sturdy like a desk, and avoid windows, mirrors, and heavy furniture that might fall such as overloaded bookshelves. Outside, avoid walls, chimneys, and electrical power lines. It is best to protect your head.

India Asteroid Killed Dinosaurs, Made Largest Crater?

The dinosaurs' demise may have been due to an asteroid double-whammy—two giant space rocks that struck near Mexico and India a few hundred thousand years apart, scientists say.
For decades one of the more popular theories for what killed the dinosaurs has focused on a single asteroid impact 65 million years ago.

A six-mile-wide (ten-kilometer-wide) asteroid is thought to have carved out the Chicxulub crater off Mexico's Yucatán Peninsula, triggering worldwide climate changes that led to the mass extinction.

But the controversial new theory says the dinosaurs were actually finished off by another 25-mile-wide (40-kilometer-wide) asteroid. That space rock slammed into the planet off the western coast of India about 300,000 years after Chicxulub, experts say.

"The dinosaurs were really unlucky," said study co-author Sankar Chatterjee, a paleontologist at Texas Tech University in Lubbock.

Chatterjee thinks this second asteroid impact created a 300-mile-wide (500-kilometer-wide) depression on the Indian Ocean seafloor, which his team began exploring in 1996.

His team has dubbed this depression the Shiva crater, after the Hindu god of destruction and renewal.

"If we are correct," Chatterjee said, "this is the largest crater known on Earth."

Dinosaur-Killer Asteroid Boosted Volcanoes?

The Shiva asteroid impact was powerful enough to vaporize Earth's crust where it struck, allowing the much hotter mantle to well up and create the crater's tall, jagged rim, Chatterjee estimates.

What's more, his team thinks the impact caused a piece of the Indian subcontinent to break off and drift toward Africa, creating what are now the Seychelles islands (see map).

The Shiva impact may also have enhanced volcanic eruptions that were already occurring in what is now western India, Chatterjee added.

Some scientists have speculated that the noxious gases released by the Indian volcanoes, called the Deccan Traps, were crucial factors in the dinosaurs' extinction.

(Related: "'Dinosaur Killer' Asteroid Only One Part of New Quadruple-Whammy Theory.")

"It's very tempting to think that the impact actually triggered the volcanism," Chatterjee said.

"But that may not be true. It looks like the volcanism was already happening, and the [Shiva] impact just made it worse."

32 New Planets Found Outside Our Solar System

Astronomers have added 32 new planets to the list of planets found orbiting stars outside our solar system. The discoveries, announced today at a press briefing in Portugal, increase to more than 400 the number of known extrasolar planets, or "exoplanets."

The 32 previously unseen planets range from five times the mass of Earth up to eight times the mass of Jupiter, scientists said. In addition, the new planets were found around different types of stars, challenging existing theories for where and how planets form. Overall, the research suggests that 40 to 60 percent of all planetary systems in the universe contain low-mass planets. Since lower masses most likely mean Earthlike sizes, such planets are considered to be the best candidates in the search for extraterrestrial life. (Related pictures: "3 Worlds Most Likely to Harbor Life Named.") "The models are predicting even larger numbers of low-mass planets like Earth, so I am pretty confident that there are Earth-type planets everywhere," said team member Stephane Udry of the Observatory of Geneva in Switzerland. "Nature doesn't like a vacuum," he added, "so if there is space to put a planet, it will put the planet there." New Planets: Super-Earths, Gas Giants The 32 new planets were found over the past five years using an instrument called a spectrograph at the European Southern Observatory in La Silla, Chile. Known as HARPS, for High Accuracy Radial velocity Planetary Searcher, the spectrograph detects wobbles in a star's orbit caused by the pull of an unseen exoplanet. The HARPS team selected stars like our sun, as well as lower-mass dwarf stars, to watch for wobbles. Red dwarf stars were targets because they are dimmer, low-mass stars, which makes it easier to detect wobbles from low-mass satellite planets, said team member Nuno Santos, of the University of Porto, Portugal. The 32 newfound exoplanets include several super-Earths, such as two planets no more than five times Earth's mass and two about six times Earth's mass, the Observatory of Geneva's Udry said. The largest newly discovered exoplanet is a monster at seven to eight times Jupiter's mass, he estimated. In addition, several Jupiter-mass planets were found around stars that don't have many metals. Previous theories had stated that planets wouldn't tend to form around metal-poor stars, since planets are thought to take shape inside the metal-filled disks of debris left over from stellar birth. The new finds suggest that astronomers might need to revise theories of planet formation—and may increase the number of possible star systems in the universe. (Related: "Turbulence Key to Planet Formation, New Study Suggests.") Exact details about each of the 32 new planets have yet to be published, Udry said, but "a bunch of the new planets will be described in the next six months." Planets and Habitability: The Next Step Counting the 32 new planets, the HARPS instrument has so far helped astronomers find 75 of the roughly 400 known exoplanets. For example, a team using HARPS had previously found several low-mass planets orbiting Gliese 581, a red dwarf star some 20.5 light-years away. One of these planets, Gliese 581 c, has been touted as the first Earthlike planet yet found outside the solar system. But for most of the newly revealed exoplanets, appraisals of their habitability will probably have to wait, the team said. "It will be very difficult to confirm a planet detected [by HARPS] is the size of the Earth and that it would also be in the habitable zone," Udry said. "We need the next generation of radio-velocity machine to do that," he said, adding that such a device should be ready in the next five years.

Tsunamis

What are Tsunamis?

A tsunami is a series of waves, generated in a body of water by an impulsive disturbance that vertically displaces the water column. Earthquakes, landslides, volcanic eruptions, explosions, and even the impact of cosmic bodies, such as meteorites, can generate tsunamis. Tsunamis can savagely attack coastlines, causing devastating property damage and loss of life.

How are Tsunamis formed?

Tsunamis can be generated when the sea floor abruptly deforms and vertically displaces the overlying water. Tectonic earthquakes are a particular kind of earthquake that are associated with the earth's crustal deformation; when these earthquakes occur beneath the sea, the water above the deformed area is displaced from its equilibrium position. Waves are formed as the displaced water mass, which acts under the influence of gravity, attempts to regain its equilibrium. When large areas of the sea floor elevate or subside, a tsunami can be created.

Large vertical movements of the earth's crust can occur at plate boundaries. Plates interact along these boundaries called faults. Around the margins of the Pacific Ocean, for example, denser oceanic plates slip under continental plates in a process known as subduction. Subduction earthquakes are particularly effective in generating tsunamis.

A tsunami can be generated by any disturbance that displaces a large water mass from its equilibrium position. In the case of earthquake-generated tsunamis, the water column is disturbed by the uplift or subsidence of the sea floor. Submarine landslides, which often accompany large earthquakes, as well as collapses of volcanic edifices, can also disturb the overlying water column as sediment and rock slump downslope and are redistributed across the sea floor. Similarly, a violent submarine volcanic eruption can create an impulsive force that uplifts the water column and generates a tsunami. Conversely, supermarine landslides and cosmic-body impacts disturb the water from above, as momentum from falling debris is transferred to the water into which the debris falls. Generally speaking, tsunamis generated from these mechanisms, unlike the Pacific-wide tsunamis caused by some earthquakes, dissipate quickly and rarely affect coastlines distant from the source area.

How does a tsunami occur?

As a tsunami leaves the deep water of the open ocean and travels into the shallower water near the coast, it transforms. A tsunami travels at a speed that is related to the water depth - hence, as the water depth decreases, the tsunami slows. The tsunami's energy flux, which is dependent on both its wave speed and wave height, remains nearly constant. Consequently, as the tsunami's speed diminishes as it travels into shallower water, its height grows. Because of this shoaling effect, a tsunami, imperceptible at sea, may grow to be several meters or more in height near the coast. When it finally reaches the coast, a tsunami may appear as a rapidly rising or falling tide, a series of breaking waves, or even a bore.

As a tsunami approaches shore, it begins to slow and grow in height. Just like other water waves, tsunamis begin to lose energy as they rush onshore - part of the wave energy is reflected offshore, while the shoreward-propagating wave energy is dissipated through bottom friction and turbulence. Despite these losses, tsunamis still reach the coast with tremendous amounts of energy. Tsunamis have great erosional potential, stripping beaches of sand that may have taken years to accumulate and undermining trees and other coastal vegetation. Capable of inundating, or flooding, hundreds of meters inland past the typical high-water level, the fast-moving water associated with the inundating tsunami can crush homes and other coastal structures. Tsunamis may reach a maximum vertical height onshore above sea level, often called a runup height, of 10, 20, and even 30 meters.

Safety first for tsunamis

If you are on land:

	If you are in school and you hear there is a tsunami warning, you should follow the advice of teachers and other school personnel.
	If you are at home and hear there is a tsunami warning, you should make sure your entire family is aware of the warning. Your family should evacuate your house if you live in a tsunami evacuation zone. Move in an orderly, calm and safe manner to the evacuation site or to any safe place outside your evacuation zone. Follow the advice of local emergency and law enforcement authorities.
	If you are at the beach or near the ocean and you feel the earth shake, move immediately to higher ground, DO NOT wait for a tsunami warning to be announced. Stay away from rivers and streams that lead to the ocean as you would stay away from the beach and ocean if there is a tsunami.
	Tsunamis generated in distant locations will generally give people enough time to move to higher ground. For locally-generated tsunamis, where you might feel the ground shake, you may only have a few minutes to move to higher ground.
	High, multi-story, reinforced concrete hotels are located in many low-lying coastal areas. The upper floors of these hotels can provide a safe place to find refuge should there be a tsunami warning and you cannot move quickly inland to higher ground. Local Civil Defense procedures may, however, not allow this type of evacuation in your area. Homes and small buildings located in low-lying coastal areas are not designed to withstand tsunami impacts. Do not stay in these structures should there be a tsunami warning.
	Offshore reefs and shallow areas may help break the force of tsunami waves, but large and dangerous wave can still be a threat to coastal residents in these areas. Staying away from all low-lying areas is the safest advice when there is a tsunami warning.

If you are on a boat:

	Keep in contact with the authorities should a forced movement of vessel be directed.
	If you are aware there is a tsunami warning and you have time to move your vessel to deep water, then you may want to do so in an orderly manner, in consideration of other vessels. Owners of small boats may find it safest to leave their boat at the pier and physically move to higher ground, particularly in the event of a locally-generated tsunami. Concurrent severe weather conditions (rough seas outside of safe harbor) could present a greater hazardous situation to small boats, so physically moving yourself to higher ground may be the only option.
	Damaging wave activity and unpredictable currents can effect harbors for a period of time following the initial tsunami impact on the coast. Contact the harbor authority before returning to port making sure to verify that conditions in the harbor are safe for navigation and berthing.

Mermaid found after TSUNAMI

BRAIN STROKE

id you know that brain stroke, the most common life-threatening neurological disease, is the third largest killer after heart attacks and cancer?

Get these facts:

Fact I: According to an independent study in India, between 100 and 268 persons in a population of 100,000 are struck by brain strokes. About 20 percent of heart patients are susceptible to it.

Fact II: A World Health Organisation study has quoted the incidence of stroke in India to be 73 of 100,000 persons per year.

Fact III: It is also the most common cause of disability and dependence, with more than 70 percent of stroke survivors remaining vocationally impaired and more than 30 percent requiring assistance with activities for daily living.

June 24 is observed every year as the World Brain Stroke Day. Dr Harsh Rastogi, Senior Consultant, Interventional Neuro-Radiology at New Delhi's [ Images ] Apollo Hospital, tell us more.

He has some good news too: brain stroke can now be treated without surgery.

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Recognising brain stroke

As compared to a heart attack, the awareness about a brain stroke, which is even more debilitating, is very limited.

People are either not aware of the symptoms of a brain stroke and, if they are, they do not know how to cope with the illness. At one time, it was believed little could be done to treat a stroke.

If a stroke victim receives emergency care within the first three to six hours of the first symptom, the disabling, long-term effects of a stroke may be avoided or greatly reduced.

Unfortunately, many people do not recognise the warning signs of a stroke or do not know that immediate emergency care can greatly improve their chance of recovery.

Studies show that the average person waits 13 hours after experiencing the first symptoms of a stroke before seeking medical care, and 42 percent of patients wait as long as 24 hours.

It is critical to recognise the symptoms of a stroke and seek immediate emergency attention.

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What causes a brain stroke?

A stroke occurs when a blood vessel carrying oxygen and nutrients to the brain is blocked by a clot or bursts, causing the brain to starve.

If deprived of oxygen for even a short period of time, the brain nerve cells will start to die.

Once the brain cells die from lack of oxygen, the part of the body controlled by that section of the brain is affected through paralysis, loss of language, motor skills or vision.

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2 types of stroke

i. Ischemic Strokes

Ischemic strokes -- which are basically blood clots that block the artery -- are the most common type, causing between 70 to 80 percent of all strokes.

When a blood vessel ruptures, it causes a bleeding or hemorrhagic stroke.

Such strokes are usually the result of a ruptured blood vessel or an aneurysm -- a weakened area of a blood vessel that bulges or balloons out.

Approximately 20 percent of strokes are hemorrhagic. This is the most common type of stroke in young people. Using the latest technology, coils as small as 2 mm can cure strokes without undergoing any surgery.

ii. Transient Ischemic Attacks

'Mini-strokes' are known as transient ischemic attacks. People who have one TIA are likely to have another one.

TIAs cause brief stroke symptoms that go away after a few minutes or hours.

People often ignore these symptoms, but they are an early warning sign and 35 percent of those who experience a TIA will have a full blown stroke if left untreated.

TIAs should be taken as seriously as a stroke.

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Watch out for these symptoms

The most common symptoms of stroke are:

i. Sudden numbness or weakness in the face, arm and/ or leg, especially on one side of the body.

ii. Sudden confusion, trouble speaking or understanding speech.

iii. Sudden trouble in seeing, including double vision, blurred vision or partial blindness, in one or both eyes.

iv. Trouble in walking, dizziness, loss of balance or coordination.

v. Sudden severe, headache with no known cause.

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What are the risk factors for stroke?

If you have the following conditions/ habits you may be at a higher-than-average risk level as far as a brain stroke is concerned.

i. High blood pressure

High blood pressure, or hypertension, puts stress on the walls of blood vessels and can lead to strokes from blood clots or hemorrhage. Half or more of all stroke victims have uncontrolled high blood pressure.

Fortunately, this risk factor can be controlled.

Eating a balanced diet, maintaining a healthy weight and exercising regularly can help control high blood pressure.

Medications that lower blood pressure may also be prescribed.

ii. High cholesterol

High cholesterol can lead to blockage in the carotid artery that takes blood from the neck to the brain. A piece of this plaque can break off and travel to the brain causing a stroke.

iii. Heart disease

Approximately 15 percent of all stroke victims have a common heart rhythm disorder called atrial fibrillation, that causes the upper chambers of the heart (the atria) to quiver instead of beating which allows the blood to pool and clot. If a clot breaks off and enters the blood stream to the brain, a stroke will occur.

iv. Personal history of stroke or TIA

People who have already suffered a stroke or TIA face an increased risk of having another.

Modifying risk factors for stroke, including lifestyle changes (eg exercise, stop smoking), medications and/ or other treatments can reduce this risk.

v. Lifestyle risk factors

Smoking, excessive alcohol consumption and being overweight are all significant risk factors for stroke.

vi. Age, gender and race

The risk of stroke goes up with age, with two-thirds of all strokes occurring in individuals 65 years or older. Twenty-eight percent of strokes occur in people under the age of 65. Men have a slightly higher risk than women although more women die from strokes.

vii. Family history of stroke or TIA

If others in your family have suffered aa stroke, you may be at higher risk. Regular physical exams, lifestyle changes and medical treatments may reduce this risk.

viii. Diabetes

People with diabetes are at increased risk, although keeping diabetes under control with diet and/ or medication may help to decrease the risk.

ix. Sickle cell anemia

Sickle cell anemia makes red blood cells less able to carry blood to the body's tissues and organs. They also stick to the walls of the blood vessels which can block the arteries to the brain, causing a stroke.

x. Hyper-homocysteinemia

Elevated homocysteine levels in the blood have been identified as a risk factor for heart attack and stroke that may be as important as high cholesterol.

Homocysteine is a by-product of the process that metabolides methionine, an amino acid essential for human nutrition.