Comparing LCD and Traditional CRT monitors

Characteristics	LCD Displays	CRT Monitors
Physical size	Thin, compact and lightweight. Takes up less space.	Bulky, heavier and takes up more space.
Brightness	LCDs are backlit and have different levels of brightness and capable of producing very bright images and shows extremely uniform brightness. Very suitable for environments that are brightly lit.	Fairly bright, but not as bright as LCDs. Brightness is not a necessary concern with CRTs. Not appropriate for brightly lit conditions.
Power Consumption and Heat	Energy efficient. Consume less electricity than a CRT and produce little heat.	Use more power and produce more heat than a LCD.
Radiation Emission	Emit considerably lesser radiation.	Emit harmful radiation.
Display Size	Advance LCD technology make colour LCD monitors comparable in screen size to CRT monitors	Wide ranges of screen sizes.
Colours	Capable of displaying hundreds or thousands of colours, but newer ones are capable of unlimited colours.	Capable of displaying unlimited colours.
Resolution	Works best at its own native resolution. The native resolution is generally the highest resolution that the LCD can display. Changing to other resolutions require adjusting procedures which can cause considerable deterioration of the image.	Capable of displaying multiple video resolutions, each with the same good quality. Highest pixel resolution was available for operation.
Viewing Angle	Restricted viewing angles. Needed to be viewed in front to have a better view. Not much of an issue for newer LCDs.	Viewable from almost every angle.
Price	More expensive but saves more electricity.	Less expensive but more electricity consuming.

Food preservation

The basic idea behind all forms of food preservation is either:

• ·         To slow down the activity of disease-causing bacteria
• ·         To kill the bacteria altogether

I­n certain cases, a preservation technique may also destroy enzymes naturally found in a food that cause it to spoil or discolor quickly. An enzyme is a special protein that acts as a catalyst for a chemical reaction, and enzymes are fairly fragile. By increasing the temperature of food to about 150 degrees Fahrenheit (66 degrees Celsius), enzymes are destroyed. A food that is sterile contains no bacteria. Unless sterilized and sealed, all food contains bacteria. 

Different techniques used for preservation.

Refrigeration and Freezing

 In the case of refrigeration, the idea is to slow bacterial action to a crawl so that it takes food much longer  to spoil. In the case of freezing, the idea is to stop bacterial action altogether. Frozen bacteria are completely inactive.

Refrigeration and freezing are used on almost all foods: meats, fruits, vegetables, beverages, etc. In general, refrigeration has no effect on a food's taste or texture. Freezing has no effect on the taste or texture of most meats, has minimal effects on vegetables, but often completely changes fruits (which become mushy). Refrigeration's minimal effects account for its wide popularity.

Canning Food

 In canning, you boil the food in the can to kill all the bacteria and seal the can (either before or while the food is boiling) to prevent any new bacteria from getting in. We generally think of "cans" as being metal, but any sealable container can serve as a can. One problem with canning, and the reason why refrigeration or freezing is preferred to canning, is that the act of boiling food in the can generally changes its taste and texture (as well as its nutritional content).

Dehydrating Food 

Water content in the food is removed. Since most bacteria die or become completely inactive when dried, dried foods kept in air-tight containers can last quite a long time. e.g.

·         Powdered milk

·         Dried fruits and vegetables

·         Powdered soups and sauces

·         Pasta

·         Instant rice

Normally, drying completely alters the taste and texture of the food.

Freeze-Drying

Freeze-drying is a special form of drying that removes all moisture and tends to have less of an effect on a food's taste than normal dehydration does.

In freeze-drying, food is frozen and placed in a strong vacuum. The water in the food then sublimates -- that is, it turns straight from ice into vapor. Freeze-drying is most commonly used to make instant coffee, but also works extremely well on fruits such as apples.

Salting and Pickling

Salting, especially of meat, is an ancient preservation technique. The salt draws out moisture and creates an environment inhospitable to bacteria. If salted in cold weather (so that the meat does not spoil while the salt has time to take effect), salted meat can last for years.

Pickling was widely used to preserve meats, fruits and vegetables in the past, but today is used almost exclusively to produce "pickles,". Pickling uses the preservative qualities of salt (see above) combined with the preservative qualities of acid, such as acetic acid (vinegar). Acid environments inhibit bacteria.

Pasteurizing, Fermenting, Carbonating

Pasteurizing

It involves heating the food to a high enough temperature to kill certain (but not all) bacteria and to disable certain enzymes, and in return you are minimizing the effects on taste as much as you can. Commonly pasteurized foods include milk, ice cream, fruit juices.

Fermenting

Fermentation uses bacteria like yeast to produce alcohol. Alcohol is a good preservative because it kills bacteria. When you ferment grape juice you create wine, which will last quite a long time (decades if necessary) without refrigeration.

Carbonating

Carbonated water is water in which carbon dioxide gas has been dissolved under pressure. By eliminating oxygen, carbonated water inhibits bacterial growth. Carbonated beverages (soft drinks) therefore contain a natural preservative.

Chemical Food Preservation

There are three classes of chemical preservatives commonly used in foods:

·         Benzoates (such as sodium benzoate)

·         Nitrites (such as sodium nitrite)

·         Sulphites (such as sulphur dioxide)

Another common preservative is sorbic acid. All of these chemicals either inhibit the activity of bacteria or kill the bacteria.

Food Irradiation

Nuclear radiation is able to kill bacteria without significantly changing the food containing the bacteria. So if you seal food in plastic and then radiate it, the food will become sterile and can be stored on a shelf without refrigeration. Unlike canning, however, you do not significantly change the taste or texture of the food when you irradiate it.

Applied/Everyday science

There is an increasing weightage in paper 2 on questions from applied/everyday science. From now onwards, we'll try to cover few application that we come accross. Please suggest if you find any other application important for exam...

http://economictimes.indiatimes.com/news/news-by-industry/et-cetera/how-does-night-vision-work/articleshow/14533494.cms

probiotic vs prebiotic

Prebiotics	Probiotics
Prebiotics are a very special form of dietary fiber.	Probiotics are living bacteria intended to benefit colon health.
Prebiotic Fiber is not affected by heat, cold, acid or time.	Probiotics must be kept alive to create health benefits. They can be killed by heat, acid or simply the passage of time.
Prebiotics nourish the thousands of good bacterial species already living in the colon.	Probiotics contain from one to a few species of bacteria which are added to the colon when they are ingested (eaten).
Prebiotic Fiber is a naturally-occurring substance, found in thousands of plant species (though mostly in very small amounts). Found in fruits, vegetables, grains.	Probiotics occur naturally in fermented foods like yogurt or Curd. Some companies have also engineered “proprietary” bacteria which they have patented and promote.
Prebiotics foster an environment in the colon which is hostile to bad bacteria.	Probiotics may impact bad bacteria by crowding them out.
Both Prebiotics and Probiotics must be ingested in sufficient quantity to have an impact, and dietarily speaking both should not carry an excessive “load” of sugar, calories, carbs, etc. out of proportion to their benefit.

ET in classroom: Libor Lessons

What is Libor? 

Devised in the 1980s, the London interbank offered rate(Libor) is supposed to be a trusty financial yardstick measuring the cost incurred when banks borrow from each other across 10 major currencies and 15 borrowing periods, ranging from overnight loans to 12-month loans. Set each day, it affects the cost of everything from business-account overdrafts to credit cards to mortgages. 

SOUNDS GOOD, THEN WHY THE BARCLAYS BROUHAHA? 

Well, banks set their own Libor, and each day tell a central entity how much interest they estimate they would have to pay on such loans. 

That entity then eliminates some of the lowest and highest submissions and calculates an average from the remainder. Eighteen banks currently supply data for setting dollardenominated Libor. 

According to regulators, Barclays traders sought to skew Libor to benefit their bets. While it might be hard for one bank among many to influence Libor, regulators felt Barclays was sometimes able to do so. 

At least 12 banks are involved in the investigations around the world: the Barclays fines may herald similar penalties for other lenders. 

SHOULD WE BE WORRIED IN INDIA? 

Indian corporates who borrow based on Libor need not worry. 

A benchmark will remain at all times since more than $350 trillion worth securities trade with Libor as benchmark. UK regulators working to fix the imbalances. 

ARE THERE ANY ALTERNATIVES? 

Alternative benchmarks could evolve overtime. Even if someone wants not to benchmark against Libor, they could choose 10 year US treasuries, or other such liquid securitied.

India Design Council

India Design Council - an autonomous body, established by the Government of India, functioning under the aegis of Department of Industrial Policy & Promotion, Ministry of Commerce & Industry. It grants India Design Mark, which recognizes and evaluates good design through a systemized process. It constitutes the India Design Mark logo that reflects the virtues of good design, which can be used as a symbol of distinguished excellence of the product.


India Design Mark is a design standard. It is not a contest. It is a certification of design excellence. It is granted to an applicant after following a diligent evaluation process aimed at identifying good design that exceeds the prescribed criteria of evaluation.

Wireless vortex beams

American and Israeli researchers have used twisted vortex beams to transmit data at 2.5 terabits per second. As far as we can discern, this is the fastest wireless network ever created — by some margin. This technique is likely to be used in the next few years to vastly increase the throughput of both wireless and fiber-optic networks.

These twisted signals use orbital angular momentum (OAM) to cram much more data into a single stream. In current state-of-the-art transmission protocols (WiFi, LTE, COFDM), we only modulate the spin angular momentum (SAM) of radio waves, not the OAM.

SAM differs from OAM in the same way that the Earth's spin differs from its orbit around our Sun -- imagine SAM as a spinning planet and think of OAM as the orbit of that spinning planet as it travels around a star.

Just as the rotational speed of SAM can be used to represent different numbers (i.e. data represented by the number of spins per second), the tightness of spirals produced by OAM can also represent numbers (faster the twist, tighter the spiral). Ultimately, researchers have managed to simultaneously utilize both SAM and OAM to represent data with light, giving them tremendous potential to represent huge ranges of information and deliver it at light speed.

Artificial neural network (Artificial brain)

• Our Biological neural networks are made up of real biological neurons that are connected or functionally related in a nervous system. 
• Artificial neural networks are composed of interconnecting artificial neurons (programming constructs that mimic the properties of biological neurons).
•  Artificial neural networks may either be used to gain an understanding of biological neural networks, or for solving artificial intelligence problems without necessarily creating a model of a real biological system.
• Google engineers claim they've designed a computer network capable of analyzing, categorizing and ultimately teaching itself to recognize the content of images. The "neural network" was fed 10 million images from YouTube video thumbnails and -- without being told how -- created its own concept of what a cat is.

RBI warns against worsening risks to financial stability - Indian Express

RBI warns against worsening risks to financial stability - Indian Express