Picture of the Day

A combo of pictures created on June 18, 2010 shows Japan's electronics giant Hitachi's humanoid robot 'Emiew2', 80 cm tall and weighing 14 kg, standing up from a kneeling position at the company's laboratory in Tokyo on June 18, 2010.

The robot is also equipped with 14 microphones on its helmet which can pick out human voices from background noise. AFP

Controller-Free Xbox Gets a Name: “Kinect”

Tech USA Today has revealed that the Xbox 360’s new motion gaming peripheral will be called “Microsoft Kinect,” replacing “Project Natal,” the old development name. There are also some new details about the games that will be available for the device.
As we reported earlier today, one of the games will be a white water rafting simulation. It turns out that game (River Rush) will actually be part of a suite of games called Kinect Adventures. Another suite titled Kinect Sports will… Continue Reading

10-10 Series (Karl Landsteiner)

1. When did Karl Landsteiner win Nobel Prize for Medicine?
a) 1930

2. When was Karl Landsteiner born?
b) 14 June 1868

3. Where was Karl Landsteiner born?
d) Vienna

4. Which university did Karl Landsteiner attend?
c) Vienna

5. When did Karl Landsteiner publish his discovery of human ABO blood group system?
a) 1901

6. For what did Karl Landsteiner win Nobel Prize for Medicine?
b) Discovery of human blood groups

7. Who co-discovered Rhesus System with Karl Landsteiner?
c) Alexander Wiener

8. When did Karl Landsteiner publish The Specificity of Serological Reactions?
d) 1936

9. When did Karl Landsteiner die?
b) 26 June 1943

10. Where did Karl Landsteiner die?
d) New York

Siddha system of medicine

 

Siddha system of medicine is practiced in some parts of South India especially in the state of Tamilnadu. It has close affinity to Ayurveda yet it maintains a distinctive identity of its own. This system has come to be closely identified with Tamil civilization.  

 

The term ‘Siddha’ has come from ‘Siddhi’- which means achievement.  

 

Siddhars were the men who achieved supreme knowledge in the filed of medicine, yoga or tapa (meditation) (Narayanaswamy, 1975).

 

It is a well-known fact that before the advent of the Aryans in India a well-developed civilization flourished in South India especially on the banks of rivers Cauvery, Vaigai, Tamiraparani etc. The system of medicine in vogue in this civilization seems to be the precursor of the present day Siddha system of medicine. During the passage of time it interacted with the other streams of medicines complementing and enriching them and in turn getting enriched. 

 

The materia medica of Siddha system of medicine depends to large extent on drugs of metal and mineral origin in contrast to Ayurveda of earlier period, which was mainly dependent upon drugs of vegetable origin.

 

According to the tradition eighteen Siddhars were supposed to have contributed to the development of Siddha medicine, yoga and philosophy. However, literature generated by them is not available in entirety. In accordance with the well-known self-effacing nature of ancient Indian Acharyas (preceptors) authorship of many literary work of great merit remains to be determined. There was also a tradition of ascribing the authorship of one's work to his teacher, patron even to a great scholar of the time. This has made it extremely difficult to clearly identify the real author of many classics.

 

 

WiMAX - Worldwide Interoperability for Microwave Access

WiMAX is a wireless digital communications system, also known as IEEE 802.16, that is intended for wireless "metropolitan area networks". 

WiMAX can provide broadband wireless access (BWA) up to 30 miles (50 km) for fixed stations, and 3 - 10 miles (5 - 15 km) for mobile stations. In contrast, the WiFi/802.11 wireless local area network standard is limited in most cases to only 100 - 300 feet (30 - 100m).

With WiMAX, WiFi-like data rates are easily supported, but the issue of interference is lessened. WiMAX operates on both licensed and non-licensed frequencies, providing a regulated environment and viable economic model for wireless carriers.

WiMAX can be used for wireless networking in much the same way as the more common WiFi protocol. 


WiMAX is a second-generation protocol that allows for more efficient bandwidth use, interference avoidance, and is intended to allow higher data rates over longer distances.

Nanotechnology

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Nano is actually a SI prefix denoting 0.000 000 001, and for instance one nano-meter means one billionth of a meter. Obviously nano is referring to the fields dealing with such small scales (roughly 1–100 nm). It should be emphasized that ‘nano’ as a field of study, deals with size; and nano scale of e.g. time, concentration, etc are not normally considered as the nano discipline (the reason is given below).

Nanotechnology describes the creation and utilisation of functional materials, devices and systems with novel functions and properties that are based either on geometrical size or on material-specific peculiarities of nano-structures. Purely geometrically the prefix “nano” (greek: dwarf) describes a scale 1000 times smaller than that of present elements of the micrometer-sphere (1nm corresponds to the millionth part of a mm). This scale has become accessible both by application of new physical instruments and procedures and by further diminution of present microsystems. Also structures of animated and non-animated nature were used as models for self-organising matter. Only if the mastery of this atomic and molecular dimension succeeds, the prerequisites for the optimisation of product properties within socioeconomic areas such as energy engineering, environmental technology as well as in information technology, health and ageing can be developed.

Mad Cow Disease

What Is Mad Cow Disease?

Mad cow disease is an incurable, fatal brain disease that affects cattle and possibly some other animals, such as goats and sheep. The medical name for mad cow disease is bovine spongiform encephalopathy (pronounced: bo-vine spun-jih-form en-seh-fah-la-puh-thee), or BSE for short.

It's called mad cow disease because it affects a cow's nervous system, causing a cow to act strangely and lose control of its ability to do normal things, such as walk.

How Do People Get It?

Only certain animals can get BSE — people don't actually get mad cow disease. However, experts have found a link between BSE and a rare brain condition that affects people, called variant Creutzfeldt-Jakob disease (vCJD). Researchers believe that people who eat beef from cows that have BSE are at risk of developing a form of vCJD.

Types of bonds: Covalent bonds

It is often the forces, or bonds, between the atoms which provide the initial clues about why certain substances have specific properties 

The nature of the bond dictates many of the physical properties of a substance - viz. the remarkable differences between diamond and graphite, though they are both forms
of Carbon.

What holds electrically neutral atoms together into molecules and even larger groups - as liquids and solids ?
Bonding between atoms to form large aggregates is possible when the energy of the combined system is less than that of the system of separate noninteracting atoms.

Stability of bonding is determined by
(i) Coulomb attraction between opposite charges (Potential Energy contribution) and
(ii) lowering of Kinetic Energy by delocalization of the wavefunction of the electrons participating in the bonding.

We will look at four types of bonds: covalent, ionic, metallic and Van der Waals [Hydrogen bond is essentially an especially strong type of Van der Waals bond].

Bonds between atoms are of the followng types:
Ionic bonds
Covalent bonds
Metallic bonds

What are the possibilities when two atoms are brought close to each other ?:
1. A covalent bond is formed - through sharing of one or more pairs of electrons by the two atoms - the KE of participating electrons is lowered (by Uncertainty Principle)
2. An ionic bond is formed - an extreme case of covalent bond, when one or more electrons from one atom is transferred to the other
3. No bond is formed - when the electronic structure of two atoms overlap they form a single system and are subject to Pauli exclusion principle - may result in electrons being pushed to higher energy states making the bond unstable. .

Mechanism of the Covalent Bond
How is it possible for two nuclei to share an electron -- quantum tunneling of the electron wavefunction with high frequency
Why electron sharing leads to lower total energy and a stable system -- if the electron occupies a larger volume, the uncertainty principle implies lower momentum and hence lower KE.
.
Examples:

• H₂⁺ molecular ion (2 protons, 1 electron): spatially symmetric wavefunction most stable giving a bond energy of 2.65 eV.
• H₂ molecular ion (2 protons, 2 electrons): spatially symmetric, spin antiparallel wavefunction most stable.
• Complex molecules: the stability of the bonding is determined by the outermost (valence) electrons only. Alterations in the valence electron wavefunctions due to interaction with other atoms determine the geometry of the bond and gives rise to the directed nature of covalent molecular bonds. Example: tetrahedral structure of diamond, methane (CH₄).

Why He₂ or H₃ cannot exist ? Why is water (H₂O) molecule stable ? : Pauli exclusion principle
Bottomline:
All covalent crystals are hard (diamond is the hardest substance known), have high melting point, are insulators and are insoluble in all ordinary liquids. Cohesive energies of 6-12 eV/atom are typical for covalent bonds.

Looking further ?

Fullerenes (e.g., C60, pictured on the left ) are formed by sp2 type of covalent bonds between neighboring Carbon atoms.

What is ligand?

In chemistry, a ligand is an atom, ion or functional group that is bonded to one or more central atoms or ions, usually metals generally through co-ordinate covalent bond. An array of such ligands around a centre is termed a complex.

The central atom usually has a positive charge which is stabilised by donation of negative charge from the ligands.

Neutral or negatively charged centres are also known, usually stabilised by donating electron density back to the ligand in a process known as "back-bonding". 

The charge on the central atom constrains the number of ligands that may be bonded, since each type of ligand donates a characteristic number of electrons and there is a requirement for overall neutrality. If the directly-bonded ligands (the "inner-sphere" ligands) do not balance the charge, this may be done by purely ionic interaction with another set of ions (the "outer-sphere" ligands).

The inner-sphere ligands arrange themselves in a certain geometry, fixed for a given complex but in some cases mutable by reaction to another stable isomer. Ligands which bind to the central atom through more than one site of their own are termed polydentate; a ligand binding through two sites, for example, is bidentate.

Wilson's Disease: Inherited Disease of Toxic Copper Accumulation

Due to a failure of copper excretion in the liver, toxic levels of copper build up and cause damage to the liver and central nervous system.

Wilson's disease or Wilson disease or hepatolenticular degeneration is an inherited disorder involving toxic accumulation of copper in the liver and the central nervous system (CNS). Accumulation in the CNS usually occurs in the sites of the basal ganglia and globus pallidus. These symptoms are all due to a failure of copper excretion by the liver.

Genetics of Wilson Disease

The incidence of Wilson's disease is 3 in 100 000. It is an autosomal recessive disorder where there is a mutation on the ATP7B gene, an ATPase, which is a copper transporter on chromosome 13. There are many known mutations but the most common is HIS1069GLU which is most common in the European population.

Clinical Features of Wilson's Disease

Children can present with liver disease and this can be expressed as fulminant liver failure, hepatitis, or cirrhosis. In young adults, one can see CNS signs such as tremor, dysarthria, dysphagia, dyskinesias, dystonias, dementia, and parkinsonism. They can also develop affective features such as depression or mania, labile emotions, fluctuating libido and personality changes. With regards to their cognition, memory can decrease and problem solving can become increasingly difficult. A famous sign of Wilson disease is the presence of Kayser-Fleischer rings, which are copper deposits in the iris.

Tests and Diagnosis of Wilson Disease

In patients with Wilson's disease, serum copper and serum caeruoplasmin are usually decreased. One can test with a 24 hour urinary copper excretion. Molecular testing is available to look for mutations in the ATP7B gene and to make a definitive diagnosis. Magnetic resonance imaging (MRI) is often used to look for signs of basal ganglia degeneration.

Management and Treatment of Wilson's Disease

Patients with Wilson's disease are on lifelong penicillinamine.

Penicillinamine is a metabolite of peniciliin but it has no antibiotic properties. It is a chelating agent that binds to accumulated copper and is then eliminated through the urine. Some possible side effects of penicillinamine are nausea, rash, low white cell count, anemia, thrombocytopenia, and haematuria.

Read more at Suite101: Wilson's Disease: Inherited Disease of Toxic Copper Accumulation http://humangenetics.suite101.com/article.cfm/wilsons-disease--inherited-disease-of-toxic-copper-accumulation#ixzz0qAXdgfjh

Liver

is the only internal human organ which can regenerate

What is the Liver?

The liver is the largest glandular organ of the body. It weighs about 3 lb (1.36 kg). It is reddish brown in color and is divided into four lobes of unequal size and shape. The liver lies on the right side of the abdominal cavity beneath the diaphragm. Blood is carried to the liver via two large vessels called the hepatic artery and the portal vein. The heptic artery carries oxygen-rich blood from the aorta (a major vessel in the heart). The portal vein carries blood containing digested food from the small intestine. These blood vessels subdivide in the liver repeatedly, terminating in very small capillaries. Each capillary leads to a lobule. Liver tissue is composed of thousands of lobules, and each lobule is made up of hepatic cells, the basic metabolic cells of the liver.

What is its major function?

The liver has many functions. 

Some of the functions are: 

-to produce substances that break down fats,

-convert glucose to glycogen,

-produce urea (the main substance of urine),

-make certain amino acids (the building blocks of proteins), 

-filter harmful substances from the blood (such as alcohol), 

-storage of vitamins and minerals (vitamins A, D, K and B12) and 

-maintain a proper level or glucose in the blood. 

-The liver is also responsible for producing cholesterol. It produces about 80% of the            cholesterol in your body.

Diseases of the Liver

Several diseases states can affect the liver. Some of the diseases are Wilson's Disease, hepatitis (an inflammation of the liver), liver cancer, and cirrhosis (a chronic inflammation that progresses ultimately to organ failure). Alcohol alters the metabolism of the liver, which can have overall detrimental effects if alcohol is taken over long periods of time.

Hemochromatosis can cause liver problems.

Medications that negatively effect the liver

Medications have side effects that may harm your liver. Some of the medications that can damage your liver are: serzone, anti-cancer drugs (tagfur, MTX, and cytoxan), and medications used to treat diabetes.

Serzone is a prescription drug manufactured by Bristol-Myers Squibb for the treatment of depression.

The possible side effects of Serzone® are: agitation, dizziness, clumsiness or unsteadiness, difficulty concentrating, memory problems, confusion, severe nausea, gastroenteritis, abdominal pain, unusually dark urine, difficult or frequent urination, fainting, skin rash or hives yellowing of the skin or whites of the eyes (jaundice) or a prolonged loss of weight or loss of appetite.

If you or a family member have suffered serious side effects or a fatal injury after taking Serzone®, you or the family member may be eligible to file a claim against the manufacturer. You should contact an attorney that specializes in class action lawsuits immediately.

To help prevent liver damage, let your doctor know about your liver condition when being treated for other conditions. Medications come in many forms and it is best to find out what is in them and what it can do to your liver.

Instrument landing system

An instrument landing system (ILS) is a ground-based instrument approach system that provides precision guidance to an aircraft approaching and landing on a runway, using a combination of radio signals and, in many cases, high-intensity lighting arrays to enable a safe landing during instrument meteorological conditions (IMC), such as low ceilings or reduced visibility due to fog, rain, or blowing snow.

Instrument approach procedure charts (or approach plates) are published for each ILS approach, providing pilots with the needed information to fly an ILS approach during instrument flight rules (IFR) operations, including the radio frequencies used by the ILS components or navaids and the minimum visibility requirements prescribed for the specific approach.

Radio-navigation aids must keep a certain degree of accuracy (set by international standards of CAST/ICAO); to assure this is the case, flight inspection organizations periodically check critical parameters with properly equipped aircraft to calibrate and certify ILS precision.
Many airports do not have ILS.

Refuse-derived fuel (RDF)

Refuse-derived fuel (RDF) or solid recovered fuel/ specified recovered fuel (SRF) is a fuel produced by shredding and dehydrating municipal solid waste (MSW) in a converter or steam pressure treating in an autoclave.

RDF consists largely of organic components of municipal waste such as plastics and biodegradable waste. 

RDF processing facilities are normally located near a source of MSW and, while an optional combustion facility is normally close to the processing facility, it may also be located at a remote location.

SRF can be distinguished from RDF in the fact that it is produced to reach a standard such as CEN/343 ANAS.

 

Strengths and Weaknesses of Refuse Derived Fuel Units

Strengths	Weaknesses
Integrated – offers front end recycling activity, with energy recovery of balance	Requires secure markets for fuel e.g. an industrial estate
Organic fraction can be recycled aerobically (composting) or anaerobically (AD)	RDF is in competition with other fuels
If densified, RDF can be stored for extended periods (coarse RDF is more suited for direct on-site use and cannot be stored)	Processing involves high electrical power consumption and maintenance
RDF can be processed to half the calorific value of coal	Poor UK operating experience of older RDF plants including reliability and air pollution control
Lower level of heavy metals in the RDF	Fuel production space required
RDF can be co-fired with other fuels in a variety of industrial boilers	RDF can cause more damage to boilers and pipework than other fuels

Preservatives

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All food products except for the one growing in your kitchen garden has food preservatives in them. Every manufacturer adds food preservative to the food during processing. The purpose is generally to avoid spoilage during the transportation time.

Food is so important for the survival, so food preservation is one of the oldest technologies used by human beings to avoid its spoilage. Different ways and means have been found and improved for the purpose. Boiling, freezing & refrigeration, pasteurizing, dehydrating, pickling are the traditional few. Sugar and salt are also often used as preservatives food. Nuclear radiation is also being used now as food preservatives. Modified packaging techniques like vacuum packing and hypobaric packing also work as food preservatives.

Food Preservation is basically done for three reasons

• To preserve the natural characteristics of food
• To preserve the appearance of food
• To increase the shelf value of food for storage.

Natural Food Preservatives

In the category of natural food preservatives comes the salt, sugar, alcohol, vinegar etc. These are the traditional preservatives in food that are also used at home while making pickles, jams and juices etc. Also the freezing, boiling, smoking, salting are considered to be the natural ways of preserving food. Coffee powder and soup are dehydrated and freeze-dried for preservation. In this section the citrus food preservatives like citrus acid and ascorbic acid work on enzymes and disrupt their metabolism leading to the preservation.

Sugar and salt are the earliest natural food preservatives that very efficiently drops the growth of bacteria in food. To preserve meat and fish, salt is still used as a natural food preservative.

Chemical Food Preservatives

Chemical food preservatives are also being used for quite some time now. They seem to be the best and the most effective for a longer shelf life and are generally fool proof for the preservation purpose. Examples of chemical food preservatives are:

• Benzoates (such as sodium benzoate, benzoic acid)
• Nitrites (such as sodium nitrite)
• Sulphites (such as sulphur dioxide)
• Sorbates (such as sodium sorbate, potassium sorbate

Antioxidants are also the chemical food preservatives that act as free radical scavengers. In this category of preservatives in food comes the vitamin C, BHA (butylated hydroxyanisole), bacterial growth inhibitors like sodium nitrite, sulfur dioxide and benzoic acid.

Then there is ethanol that is a one of the chemical preservatives in food, wine and food stored in brandy. Unlike natural food preservatives some of the chemical food preservatives are harmful. Sulfur dioxide and nitrites are the examples. Sulfur dioxide causes irritation in bronchial tubes and nitrites are carcinogenic.

Artificial Preservatives

Artificial preservatives are the chemical substances that stops of delayed the growth of bacteria, spoilage and its discoloration. These artificial preservatives can be added to the food or sprayed on the food.

Types of Artificial Preservatives Food

• Antimicrobial agents
• Antioxidants
• Chelating agent

In antimicrobial comes the Benzoates, Sodium benzoate, Sorbates and Nitrites.
Antioxidants include the Sulfites, Vitamin E, Vitamin C and Butylated hydroxytoluene (BHT)
Chelating agent has the Disodium ethylenediaminetetraacetic acid (EDTA), Polyphosphates and Citric acid

Harmful Food Preservatives

Although preservatives food additives are used to keep the food fresh and to stop the bacterial growth. But still there are certain preservatives in food that are harmful if taken in more than the prescribed limits.

Certain harmful food preservatives are

Benzoates

This group of chemical food preservative has been banned in Russia because of its role in triggering allergies, asthma and skin rashes. It is also considered to cause the brain damage. This food preservative is used in fruit juices, tea, coffee etc.

Butylates

This chemical food preservative is expected to cause high blood pressure and cholestrol level. This can affect the kidney and live function. It is found in butter, vegetable oils and margarine.

BHA (butylated hydroxyanisole)

BHA is expected to cause the live diseases and cancer

. This food preservative is used to preserve the fresh pork and pork sausages, potato chips, instant teas, cake mixes and many more.

Caramel

Caramel is the coloring agent that causes the vitamin B6 deficiencies, genetic effects and cancer. It is found in candies, bread, brown colored food and frozen pizza.

In addition to this there are many other harmful food preservatives. These are Bromates, Caffeine, Carrageenan, Chlorines, Coal Tar AZO Dies, Gallates, Glutamates, Mono- and Di-glycerides, Nitrates/Nitrites, Saccharin, Sodium Erythrobate, Sulphites and Tannin

Preservatives Food Additives

All of these chemicals act as either antimicrobials or antioxidants or both. They either inhibit the activity of or kill the bacteria, molds, insects and other microorganisms. Antimicrobials, prevent the growth of molds, yeasts and bacteria and antioxidants keep foods from becoming rancid or developing black spots. They suppress the reaction when foods comes in contact with oxygen, heat, and some metals. They also prevent the loss of some essential amino acids some vitamins

.

Some common preservatives and their primary activity

Chemical Affected		Organism(s)		Action			Use in Foods
Sulfites		Insects & Microorganisms		Antioxidant			Dried Fruits, Wine, Juice
Sodium Nitrite		Clostridia		Antimicrobial			Cured Meats
Propionic Acid		Molds		Antimicrobial			Bread, Cakes, Cheeses
Sorbic Acid		Molds		Antimicrobial			Cheeses, Cakes, Salad Dressing
Benzoic Acid		Yeasts & Molds		Antimicrobial			Soft Drinks, Ketchup, Salad Dressings

There are other antioxidants like Sodium Erythorbate, Erythorbic Acid, Sodium Diacetate, Sodium Succinate, Grape Seed Extract, Pine Bark Extract, Apple Extract Tea Proplyphenols, Succinic Acid and Ascorbic Acid and food preservatives like Parabens and Sodium Dehydro Acetate used frequently for preservation.

Periodic Table

Group	1	2		3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18
Period
1	1 H																		2 He
2	3 Li	4 Be												5 B	6 C	7 N	8 O	9 F	10 Ne
3	11 Na	12 Mg												13 Al	14 Si	15 P	16 S	17 Cl	18 Ar
4	19 K	20 Ca		21 Sc	22 Ti	23 V	24 Cr	25 Mn	26 Fe	27 Co	28 Ni	29 Cu	30 Zn	31 Ga	32 Ge	33 As	34 Se	35 Br	36 Kr
5	37 Rb	38 Sr		39 Y	40 Zr	41 Nb	42 Mo	43 Tc	44 Ru	45 Rh	46 Pd	47 Ag	48 Cd	49 In	50 Sn	51 Sb	52 Te	53 I	54 Xe
6	55 Cs	56 Ba	*	71 Lu	72 Hf	73 Ta	74 W	75 Re	76 Os	77 Ir	78 Pt	79 Au	80 Hg	81 Tl	82 Pb	83 Bi	84 Po	85 At	86 Rn
7	87 Fr	88 Ra	**	103 Lr	104 Rf	105 Db	106 Sg	107 Bh	108 Hs	109 Mt	110 Ds	111 Rg	112 Cn	113 Uut	114 Uuq	115 Uup	116 Uuh	117 Uus	118 Uuo
*Lanthanoids			*	57 La	58 Ce	59 Pr	60 Nd	61 Pm	62 Sm	63 Eu	64 Gd	65 Tb	66 Dy	67 Ho	68 Er	69 Tm	70 Yb
**Actinoids			**	89 Ac	90 Th	91 Pa	92 U	93 Np	94 Pu	95 Am	96 Cm	97 Bk	98 Cf	99 Es	100 Fm	101 Md	102 No

 

Element 117 discovered?

A paper just published (5 April 2010) in Physical Review Letters by Yu. Ts. Oganessian and others claims the synthesis of a new element with atomic number 117. The abstract states "The discovery of a new chemical element with atomic number Z=117 is reported. The isotopes ²⁹³117 and ²⁹⁴117 were produced in fusion reactions between ⁴⁸Ca and ²⁴⁹Bk. Decay chains involving eleven new nuclei were identified by means of the Dubna Gas Filled Recoil Separator. The measured decay properties show a strong rise of stability for heavier isotopes with Z>=111, validating the concept of the long sought island of enhanced stability for super-heavy nuclei.