It’s time to widen your knowledge on technology. Read the article on lasers and take the first step. Follow the tips to brew your coffee right to please your guests and family. The regular health column will tell you how important your diet is for a healthy life. Your contributions keep the page bright.

Flash knowledge on laser to slash worries

Dr. Kumudu Perera

Laser bears some unique features. Llasers are used frequently in various applications in the modern world. Just walk into a super market and observe the billing system. You will wonder when you see the use of laser there. The product history, price and whatever the information that you need will appear on the computer screen in a moment, thanks to laser.

Worried about your appearance? Do those wrinkles, scars and dark patches force you to keep away from the mirror? Does that back pain an other ailments run you wild? Keep reading and learn how lasers tackle all those problems.

Lasers have been used in an amazing range of products and technologies. It is possible to find them in everything from CD players to dental drills to high-speed metal cutting machines to measuring systems.

The laser disc player, introduced in 1978, was the first successful consumer product to include a laser, but the compact disc (CD) player was the first laser-equipped device to become truly common in consumers’ homes, beginning in 1982.

Today, they have become a very essential household commodity. The CD has pits etched in it, usually by lasers, and the CD player reads the type of signal which is reflected off the CD surface. This gives information about the data which is stored on the CD.

Cashiers in most supermarkets and shops use barcode scanners to read the price of goods. Items are tagged with special bar codes. The scanner understands the pattern of lines in the barcode and the computer can find the relevant information.

The information which can be stored in these barcodes, ranges from the country in which the product was made, to the type of product and its price. Actually, this first application of lasers visible in the daily lives of the general population came to existence in 1974.

The advent of lasers has provided an opportunity for an improvement in many medical techniques. In the field of medicine, lasers are used from cosmetic surgery to the correction of short-sightedness. In cosmetic surgery, lasers have a wide range of usage from the removal of tattoos to treatment of wrinkles. When laser light is focused on to a very small point, high intensities can be generated at these points.

To remove tattoos, the high intensity light is used to break up the ink which lies in the skin to make up the tattoo, into fragments. These are small enough to be removed by the body’s natural immune system. Spider veins are veins of small diameter, usually located just below the surface of the skin, that become dilated.

This condition leads to red or purple trace patterns. Further, they can also cause discomfort, and spontaneous bruising. Tracing the vein with a laser causes the vein to get heated very quickly. This destroys the vein, leaving the surrounding tissues largely unaffected. As in the case of the tattoo ink, the body’s systems break down and remove the vein tissue.

For the treatment of wrinkles, short pulses of extremely high intensity light cause the coagulation of small regions of tissue. The energy of these pulses is absorbed quickly by the target area, so that the heat transfer to the surrounding tissue is minimal.

When positioned correctly, these pulses can remove much of the visible effects of wrinkles. Opthamologists have also capitalised on the discovery of lasers and their uses in surgery, developing a number of techniques using lasers to correct myopia and hyperopia (near- and long-sightedness).

In those methods, a laser is used to alter the shape of the cornea in the patient’s eye, removing much of the risk for human error. By altering the shape of the cornea, corrections can be done for the defects in the lenses of the patient, instead of using glasses or contact lenses. Many of the patients have mentioned such a great improvement in vision that they no longer require glasses .

Light has always been a primary communication link between man and his environment. Today, Fibre optic communication stands in the front row of communication systems. There, a major role is taken by lasers.

Though lasers are very useful for numerous applications, some types of lasers are dangerous too. Even the first laser was recognised as being potentially dangerous. Today, it is accepted that even low-power lasers with only a few milliwatts of output power can be hazardous to a person’s eyesight.

Hence, they are classified into four broad areas depending on the potential for causing biological damage. Some lasers cannot emit laser radiation at known hazard levels, and there are lasers that are “not intended for viewing,” such as a supermarket laser scanner.

There are intermediate-power lasers which are hazardous only for intrabeam viewing. High-power lasers are a potential fire hazard and a skin hazard.

The writer is a Senior Lecturer, Department of Electronics, Wayamba University of

Sri Lanka, Kuliyapitiya

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Diet and arthritis( Part 2):

Eat healthily to lose weight

HEALTH: Taken together, these measures are likely to be beneficial whatever type of arthritis you have. Current evidence suggests that oily fish is likely to be beneficial if you have an inflammatory type of arthritis (such as rheumatoid arthritis, reactive arthritis, psoriatic arthritis, or ankylosing spondylitis).

Oily fish helps protect against heart disease and is good for your health in general, but the strongest evidence that it can help arthritis relates to inflammatory arthritis.

Advice relating to specific types of arthritis is given later in the article, so it is important to know what type of arthritis you have. All the points above are dealt with in more detail after I have explained why watching your weight is so important.

Why is my weight so important?

The most important single link between your diet and arthritis is certainly your weight. Being overweight puts an extra burden on the weight-bearing joints (back, hips, knees, ankles and feet) when they are already damaged or under strain.

Because of the way joints work, the pressure in your knee joints is 5-6 times your body weight when you walk. Even a small weight loss can make a big difference to your joints. If you are overweight and have arthritis in any of your weight-bearing joints losing weight will help you more than any food supplements.

Too much body fat may also increase inflammation in the body, making your joints more painful. Some evidence for this can be seen in the fact that achieving a healthier weight can improve the results of blood tests for inflammation such as CRP (C-reactive protein) and ESR (erythrocyte sedimentation rate).

How can I lose weight and eat a healthy diet?

Slimming has become big business. There are many slimming treatments and so-called miracle diets, and this can be confusing. Unfortunately there is no miracle cure for arthritis. Crash and fad diets are usually unbalanced and are not recommended.

Most people find they put weight back on when they return to normal eating. The only way to lose weight permanently is to make permanent changes to the way you eat or the amount of exercise you do.

To work normally, your body needs food to supply energy and a variety of vitamins and minerals. If your diet contains more energy than you burn up, your body will convert the extra energy to fat and you will put on weight.

On the other hand, if your food contains less energy than you are using, you will lose weight. It may be that you are unable to take as much exercise as before because of your arthritis. This means that you need less energy and should eat less high calorie foods while maintaining your intake of essential nutrients.

It is healthy to eat starchy foods like bread, potatoes, rice, and pasta. They have no more calories than protein. Wholemeal versions of these starchy foods are better as they are more filling because they are high in fibre, and often supply more vitamins and minerals - for example, wholemeal bread, brown rice, wholegrain breakfast cereals.

(To be continued)

Dr. Kaleel Cassim
MBBS, MD (Medicine)
Consultant
Rheumatologist
Sri Jayawardenepura General Hospital