INFECTION
Infection is the lodgment and mulplication of the infectious agent in or on the tissues of the host. The infection may be acquired by contact, inhalation ingestion, or inoculation, or from insects, or may be iatrogenic or congenital. It can be classified into primary infection (initial infection with an infectious agent in a host), reinfection (subsequent infection by the same infectious agents in the host and secondary infection) (a new agent set up an infection when pre-existing infectious disease lowers the resistance). Depending upon the source, infection is classified into exogenous where infection from the external sources and endogenous when infection is from the host’s own body.
Thursday, April 9, 2009
Friday, April 3, 2009
WHEN MICE WERE WOODEN
WHEN MICE WERE WOODEN
“History is bunk”, flatly and famously stated Henry Ford in 1916. We don’t quite agree. Sure, we can let bygones be bygones. But if what was done fifty or hundred years ago endures, if has changed the way we live. If it has enriched our lives-we’re interested. What was computing like when there were no mice and-no horror of it!-No color displays? A passion for technology is not limited to checking out the latest graphics cards. We want to know how it all happened: how we got married to the phenomenon called technology. This is not a history. It’s a celebration of five decades of technology and not to forget, a tribute to men who made it happen.
So while these hippies were lying on the grass and getting stoned, not everyone was convinced that t at was where the good life was. Researches in the corporate and the university labs were for the ultimate good of mankind, engaged in serious work (yes, there was a lot of that in 60’s, too). And they weren’t working on their laptops from the comfort of their homes: they got down to the dirty, as an actual hands-on work with primitive components. A few dreamers here and there wrote seminal papers. Companies some small some large introduced devices, some that fizzled out, some that endured.
“History is bunk”, flatly and famously stated Henry Ford in 1916. We don’t quite agree. Sure, we can let bygones be bygones. But if what was done fifty or hundred years ago endures, if has changed the way we live. If it has enriched our lives-we’re interested. What was computing like when there were no mice and-no horror of it!-No color displays? A passion for technology is not limited to checking out the latest graphics cards. We want to know how it all happened: how we got married to the phenomenon called technology. This is not a history. It’s a celebration of five decades of technology and not to forget, a tribute to men who made it happen.
So while these hippies were lying on the grass and getting stoned, not everyone was convinced that t at was where the good life was. Researches in the corporate and the university labs were for the ultimate good of mankind, engaged in serious work (yes, there was a lot of that in 60’s, too). And they weren’t working on their laptops from the comfort of their homes: they got down to the dirty, as an actual hands-on work with primitive components. A few dreamers here and there wrote seminal papers. Companies some small some large introduced devices, some that fizzled out, some that endured.
Sunday, March 29, 2009
THE NOBLE PRIZE
THE NOBLE PRIZE
The Noble Prize is considered the most prestigious prize in the world .It is awarded annually to people or institutions for outstanding contribution in a variety of fields for the good of humanity.
The prize is named after Alfred Nobel, who in his will directed that the interest from the funds be set aside and used to give one annual prize in each of the five fields of Physics, Chemistry, medicine and literature and the ‘most effective work in the interest of International peace’. The prizes were first presented in 1901. A sixth prize the Nobel Memorial prize in economic science was instituted in 1968, by the national bank of Sweden.
These six Nobel prizes are awarded every year on December 10th the death anniversary of Alfred Nobel. Each recipient is presented a gold medal, a certificate baring the awards name and field of achievement, and a cash prize. The abverse side of each metal has a burst of Alfred Nobel. The reverse side of each medal, other than those of Physics and Chemistry, which had identical reverse sides, is different. The rize-giving ceremony is held in Stockholm, Sweden. The peace prize, however, is awarded in Oslo, Norway.
The Prize-winners are chosen by different committee whose members are selected by the Swedish Academics and institution and the Norwegian Parliament. The candidates are chosen from among the names recommended by eminent scholars, former Nobel Prize winners and distinguished scientist. The candidate does not apply for the prize directly. Sometimes two or more winners share the prize and sometimes no candidate is found suitable for a particular prize in that year.
In his will, Alfred Nobel had mentioned: “,…It is my express wish that in awarding the prizes no consideration whatever shall be given to nationality of the candidates, but that the most worthy shall receive the prize whether he be a Scandinavian or not.”
The Noble Prize is considered the most prestigious prize in the world .It is awarded annually to people or institutions for outstanding contribution in a variety of fields for the good of humanity.
The prize is named after Alfred Nobel, who in his will directed that the interest from the funds be set aside and used to give one annual prize in each of the five fields of Physics, Chemistry, medicine and literature and the ‘most effective work in the interest of International peace’. The prizes were first presented in 1901. A sixth prize the Nobel Memorial prize in economic science was instituted in 1968, by the national bank of Sweden.
These six Nobel prizes are awarded every year on December 10th the death anniversary of Alfred Nobel. Each recipient is presented a gold medal, a certificate baring the awards name and field of achievement, and a cash prize. The abverse side of each metal has a burst of Alfred Nobel. The reverse side of each medal, other than those of Physics and Chemistry, which had identical reverse sides, is different. The rize-giving ceremony is held in Stockholm, Sweden. The peace prize, however, is awarded in Oslo, Norway.
The Prize-winners are chosen by different committee whose members are selected by the Swedish Academics and institution and the Norwegian Parliament. The candidates are chosen from among the names recommended by eminent scholars, former Nobel Prize winners and distinguished scientist. The candidate does not apply for the prize directly. Sometimes two or more winners share the prize and sometimes no candidate is found suitable for a particular prize in that year.
In his will, Alfred Nobel had mentioned: “,…It is my express wish that in awarding the prizes no consideration whatever shall be given to nationality of the candidates, but that the most worthy shall receive the prize whether he be a Scandinavian or not.”
The Luminous life of Alfred Nobel
The Luminous life of Alfred Nobel
On October 21, 1833 a bailey boy to a family in Stockholm, Sweden his father was Immanuel Nobel and his mother was Andretti Ahlell Noble.
He learnt a great deal of his own, which included learning French, by translating Voltaire first into Swedish and then back into French and checking it again the original. Alfred Noble’s expanding capacity that his revolutionary inventions the blasting cap and dynamite, patented in 1863and 1867 respectively famed the basis for operations at Vinterviken. Dynamite and detonating caps became much demanded in the construction of industry. Alfred set up factories in ninety different places. He also experimented hundred and fifty five patients in his name. He had been suffering from chronic cold and symptoms of scurry for some time and the balmy, mild climate of the Mediterranean was a welcome relief after the cold and humidity of Paris. The property that Alfred Nobel brought of the Rivera Di Puente, in 1891, had a large villa, whose exterior canned influences of the kind of architecture more widespread in the orient. He was familiar with Volaire and Rousseau the philosophers of enlightenment. He had also set out the draft of a longer novel called” Systrana” (the sisters), where he discusses faith and knowledge with free thinker called Oswald and questions the divinity of Christ .His last wish expressed that in awarding the prizes to no, the candidates but that the most worthy shall receive the prize, whether he be Scandinavian or not. He died in 1896 in his home in Sanrem, lately on December 10, 1896.
On October 21, 1833 a bailey boy to a family in Stockholm, Sweden his father was Immanuel Nobel and his mother was Andretti Ahlell Noble.
He learnt a great deal of his own, which included learning French, by translating Voltaire first into Swedish and then back into French and checking it again the original. Alfred Noble’s expanding capacity that his revolutionary inventions the blasting cap and dynamite, patented in 1863and 1867 respectively famed the basis for operations at Vinterviken. Dynamite and detonating caps became much demanded in the construction of industry. Alfred set up factories in ninety different places. He also experimented hundred and fifty five patients in his name. He had been suffering from chronic cold and symptoms of scurry for some time and the balmy, mild climate of the Mediterranean was a welcome relief after the cold and humidity of Paris. The property that Alfred Nobel brought of the Rivera Di Puente, in 1891, had a large villa, whose exterior canned influences of the kind of architecture more widespread in the orient. He was familiar with Volaire and Rousseau the philosophers of enlightenment. He had also set out the draft of a longer novel called” Systrana” (the sisters), where he discusses faith and knowledge with free thinker called Oswald and questions the divinity of Christ .His last wish expressed that in awarding the prizes to no, the candidates but that the most worthy shall receive the prize, whether he be Scandinavian or not. He died in 1896 in his home in Sanrem, lately on December 10, 1896.
Thursday, March 26, 2009
The father of Microsoft
The father of Microsoft
There are many great personalities in this would some achieve because of these character and some achieve greatness because of their intelligence these is one such great personality “Bill Gates” when richest man of the world and because of his hard work and intelligence he can be called the father of Microsoft.
Bill Gates is the chairman and chief software architect of Microsoft Corporation and the worldwide leader in software, services and Internet technologies for personal and business computing. Microsoft had revenues of US $32.19 billion for the fiscal year ending June 2003 and employees more than 54,000 people in 85 countries.
On October 28th, 1955 shortly after 9:00 pm Bill Gates was born. His father was a prominent lawyer and his mother Mary Gates was a school teacher in the University of Washington Regent and chairwoman united way International. His grandfather was a Vice President of a national bank. Thus Bill Gates was born to a family with a rich history in Business politics and community service. Bill Gates started programming at the age of 13. As a school boy he and his friend Paul in 1968 hacked into a security system of a firm computer and were then asked to look for its weakness. It was here that Gates and Ales really began to develop the talents that would lead to the formation of Microsoft seven years later.
In December of 1974, Alen was on his way to visit Gates when along the way he stopped to browse the current magazines. What he saw changed Bill Gates lives forever. On the cover of Popular Electronics was a picture of the altar 8080 and the headline world’s first Micro computer kit to Rival models. He bought the issue and rushed over to Gates dorm room. They both recognized it as a big opportunity the two knew that home computer market was about to explode and that someone would need to make the software for the machines within a few days Gates has called MITS (Micro Instrumentation and Telemetry System) makers of the Altair he told the company that he and Allen had developed a BASIC that could be used on the Altair. This was a lie. They have not written a line of code. They had neither a Altar nor the chip that man the computer.
The MITS Company did not know this was very interesting in seeing their BASIC so Gates and Allen began working feverishly on the BASIC they had promised. The code for the program was left mostly upto Bill Gates while Paul Allen began working on a way to simulate the Altair with the school PDP-10. Eight weeks two felt that their program was ready Allen was to fly MITS and show of their creation. The day after Allen arrived at MITS it was time to test their BASIC. Entering the programming into the company Altair was the first time Allen had ever touched one. If Alter simulation he designed of Gates codes was faulty the demonstration would mostly likely have ended in failure this was not the case and the program worked perfectly the first time MITS arranged a deal with Gates and Allen to buy their rights to their BASIC. Within a year Bill Gates had dropped out of Hardware to form Microsoft with Paul Allen in 1975.
Bill Gates and Paul had a vision of computers as a useful tool for everyone their big break was a contract with IBM for an Operating System for IBM’s new personal computer. In the 1980’s and 1990’s Microsoft developed and made a huge success of its Windows GUI. But its business practices brought accusation monopoly tactics.
Under Gates leadership Microsoft mission has been to continually advance and improve software technology and to make it easier more cost –effective and more enjoyable for people to sue computers. The company is committed to a long term view reflected in its investment of more than $6.8 billion on research and development in the current fiscal year.
There are many great personalities in this would some achieve because of these character and some achieve greatness because of their intelligence these is one such great personality “Bill Gates” when richest man of the world and because of his hard work and intelligence he can be called the father of Microsoft.
Bill Gates is the chairman and chief software architect of Microsoft Corporation and the worldwide leader in software, services and Internet technologies for personal and business computing. Microsoft had revenues of US $32.19 billion for the fiscal year ending June 2003 and employees more than 54,000 people in 85 countries.
On October 28th, 1955 shortly after 9:00 pm Bill Gates was born. His father was a prominent lawyer and his mother Mary Gates was a school teacher in the University of Washington Regent and chairwoman united way International. His grandfather was a Vice President of a national bank. Thus Bill Gates was born to a family with a rich history in Business politics and community service. Bill Gates started programming at the age of 13. As a school boy he and his friend Paul in 1968 hacked into a security system of a firm computer and were then asked to look for its weakness. It was here that Gates and Ales really began to develop the talents that would lead to the formation of Microsoft seven years later.
In December of 1974, Alen was on his way to visit Gates when along the way he stopped to browse the current magazines. What he saw changed Bill Gates lives forever. On the cover of Popular Electronics was a picture of the altar 8080 and the headline world’s first Micro computer kit to Rival models. He bought the issue and rushed over to Gates dorm room. They both recognized it as a big opportunity the two knew that home computer market was about to explode and that someone would need to make the software for the machines within a few days Gates has called MITS (Micro Instrumentation and Telemetry System) makers of the Altair he told the company that he and Allen had developed a BASIC that could be used on the Altair. This was a lie. They have not written a line of code. They had neither a Altar nor the chip that man the computer.
The MITS Company did not know this was very interesting in seeing their BASIC so Gates and Allen began working feverishly on the BASIC they had promised. The code for the program was left mostly upto Bill Gates while Paul Allen began working on a way to simulate the Altair with the school PDP-10. Eight weeks two felt that their program was ready Allen was to fly MITS and show of their creation. The day after Allen arrived at MITS it was time to test their BASIC. Entering the programming into the company Altair was the first time Allen had ever touched one. If Alter simulation he designed of Gates codes was faulty the demonstration would mostly likely have ended in failure this was not the case and the program worked perfectly the first time MITS arranged a deal with Gates and Allen to buy their rights to their BASIC. Within a year Bill Gates had dropped out of Hardware to form Microsoft with Paul Allen in 1975.
Bill Gates and Paul had a vision of computers as a useful tool for everyone their big break was a contract with IBM for an Operating System for IBM’s new personal computer. In the 1980’s and 1990’s Microsoft developed and made a huge success of its Windows GUI. But its business practices brought accusation monopoly tactics.
Under Gates leadership Microsoft mission has been to continually advance and improve software technology and to make it easier more cost –effective and more enjoyable for people to sue computers. The company is committed to a long term view reflected in its investment of more than $6.8 billion on research and development in the current fiscal year.
RIBOSOMES
RIBOSOMES
The ribosome is the main site for protein synthesis. It is spheroidal particle consisting of a large and a small subunit. In prokaryotes (E. coli), the intact particle has a sedimentation coefficient of 70S (S = Svedberg unit) where the small subunit is 30S and the large subunit is 50S. Each 30S subunit contains one 16S ribosomal RNA (rRNA) molecule and 21 different proteins. Each 50S subunit contains one 5S rRNA molecule, one 23S rRNA molecule and 32 different proteins. In eukaryotes, in intact particle is 80S and dissociates to give 40S small subunit and 60S large subunit. Each 40S subunit contains one 18S rRNA and 30 proteins. Each 60S subunit contains 28S rRNA, 5.8S rRNA and 40 proteins. Each subunit contains two transfer-RNA-binding sites—A-site (aminoacyl site) and P-site (peptidyl site). During proteins synthesis more ribosomes attach to a single messenger RNA molecule and form a polysome. It also protects the mRNA during protein synthesis.
The ribosome is the main site for protein synthesis. It is spheroidal particle consisting of a large and a small subunit. In prokaryotes (E. coli), the intact particle has a sedimentation coefficient of 70S (S = Svedberg unit) where the small subunit is 30S and the large subunit is 50S. Each 30S subunit contains one 16S ribosomal RNA (rRNA) molecule and 21 different proteins. Each 50S subunit contains one 5S rRNA molecule, one 23S rRNA molecule and 32 different proteins. In eukaryotes, in intact particle is 80S and dissociates to give 40S small subunit and 60S large subunit. Each 40S subunit contains one 18S rRNA and 30 proteins. Each 60S subunit contains 28S rRNA, 5.8S rRNA and 40 proteins. Each subunit contains two transfer-RNA-binding sites—A-site (aminoacyl site) and P-site (peptidyl site). During proteins synthesis more ribosomes attach to a single messenger RNA molecule and form a polysome. It also protects the mRNA during protein synthesis.
Sunday, March 22, 2009
RETROVIRUSES
RETROVIRUSES
Retroviruses have single-stranded RNA genomes, which are replicated through a double-stranded DNA intermediate. The life cycle of these viruses involves an obligatory stage in which the double stranded DNA inserted into the host genome by transposition-like event, which produces short direct repeats of 4, 5 or 6 bp in the target DNA. Each retrovirus particle contains two copies of the RNA genome, and becomes surrounded by a segment of the membrane of its host cell during its release. During infection, the membrane surrounding the virus particle fuses with plasma lemma of the new host cell and the virus particle is thereby released into the cytoplasm.
The virus particle carries along with its genome the enzyme reverse transcriptase, which converts the RNA genome into linear DNA duplex. The DNA duplex migrates into the cell nucleus, becomes inserted into the host genome in one or more copies, and is transcribed by the host machinery to yield RNA copies to itself, this RNA may function either as mRNA or as viral genome. The integration reaction is catalyzed by a single enzyme called integrase that is carried within the virus particle. The virus particle also carries an uncharged host tRNA molecule that serves as primer during reverse transcription of the viral genome.
Retroviruses have single-stranded RNA genomes, which are replicated through a double-stranded DNA intermediate. The life cycle of these viruses involves an obligatory stage in which the double stranded DNA inserted into the host genome by transposition-like event, which produces short direct repeats of 4, 5 or 6 bp in the target DNA. Each retrovirus particle contains two copies of the RNA genome, and becomes surrounded by a segment of the membrane of its host cell during its release. During infection, the membrane surrounding the virus particle fuses with plasma lemma of the new host cell and the virus particle is thereby released into the cytoplasm.
The virus particle carries along with its genome the enzyme reverse transcriptase, which converts the RNA genome into linear DNA duplex. The DNA duplex migrates into the cell nucleus, becomes inserted into the host genome in one or more copies, and is transcribed by the host machinery to yield RNA copies to itself, this RNA may function either as mRNA or as viral genome. The integration reaction is catalyzed by a single enzyme called integrase that is carried within the virus particle. The virus particle also carries an uncharged host tRNA molecule that serves as primer during reverse transcription of the viral genome.
Subscribe to:
Posts (Atom)