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#1 Re: Ganesh's Puzzles » Doc, Doc! » Yesterday 23:15:43


I am unable to provide a better explanation.

#3 Re: Ganesh's Puzzles » Oral puzzles » 2017-07-10 13:52:24


The solution #3788 (two values) are correct. Excellent, zetafunc!

#3789. Determine the nature of the roots of the following quadratic equation:


#4 Re: Ganesh's Puzzles » Oral puzzles » 2017-07-04 14:08:01


The solution #3787 is correct. Excellent, zetafunc!

#3788. Determine the nature of the roots of the following quadratic equation:


#5 Re: Ganesh's Puzzles » Oral puzzles » 2017-07-04 01:33:16


The solution #3786 is correct. Neat work, zetafunc!

#3787. Determine the nature of the roots of the following quadratic equation:


#6 Re: Ganesh's Puzzles » General Quiz » 2017-07-04 00:35:52


The Answer #6652 is correct. Neat work, zetafunc!

#6653. What is 'exarch'?

#6654. What is ' timocracy'?

#7 Re: Ganesh's Puzzles » General Quiz » 2017-07-03 22:23:32


#6651. What is 'Achernar'?

#6652. What is 'Procyon'?

#8 Re: Ganesh's Puzzles » General Quiz » 2017-07-02 21:31:36


The Answer #6647 is correct. Neat work, zetafunc!

#6649. What does the Latin phrase Annus mirabilis mean?

#6650. What does the Latin phrase De jure mean?

#9 Re: Ganesh's Puzzles » General Quiz » 2017-07-02 14:44:54


The Answer #6645 is correct. Excellent, zetafunc! Congratulations, zetafunc, on becoming a Moderator!

#6647. Who was known as 'The Great Communicator'?

#6648. Who was known as 'The Great Emancipator'?

#10 Re: Dark Discussions at Cafe Infinity » crème de la crème » 2017-07-01 00:32:59

171. Colin Murdoch

Colin Albert Murdoch (6 February 1929 – 4 May 2008) was a New Zealand pharmacist and veterinarian who made a number of significant inventions, in particular the tranquilliser gun, the disposable hypodermic syringe and the child-proof medicine container. He had a total of 46 patents registered in his name.

Biographical background

Born in Christchurch, New Zealand, in 1929, to parents Mary Kathleen and Frank William James, Murdoch displayed a talent for chemistry at a very early age. Although he struggled through his schooling years with dyslexia, Murdoch already displayed an interest in both mechanical and technical skills. At the age of ten he successfully made gunpowder and came to the realization that an ignition could be caused by the mixing of certain nitrates and sulphuric acid. This discovery led the young Murdoch to build a successful firearm using a wick and a small asbestos-filled hammer.

At the age of 13 he was awarded the Royal Humane Society Medal for saving a drowning man in the New Brighton estuary.

Murdoch later came to outgrow his dyslexia and went on to study at The College of Pharmacy in Wellington. Following this, he completed a five-year apprenticeship and, like his father, became a pharmacist. He later studied to become a veterinarian. as he had an interest in not only human welfare, but also the welfare of animals.

Disposable hypodermic syringe

Both a pharmacist and a veterinarian, Murdoch was aware of the risks in reusing syringes. There was a high risk of passing infection from one patient to the next in both humans and animals, unless the glass syringe was sterilized accurately. Wanting to eliminate these risks, and needing more effective vaccination for his animal patients, Murdoch designed and invented the disposable hypodermic syringe, a plastic version of its glass predecessor. Murdoch presented the design to officials of the New Zealand Department of Health, who were skeptical, and believed it “too futuristic”, and that it would not be received well by both doctors and patients. Development of the syringe was held off for a few years due to lack of funding. Eventually, when he was granted both patents, Murdoch’s syringe became hugely successful, with millions used throughout the world every day. It is not widely known as a New Zealand design, although Murdoch's achievements have been covered in the New Zealand media.

Tranquilliser gun

In the 1950s, while working with colleagues who were studying introduced wild goat, deer and tahr populations in New Zealand, Murdoch had the idea that the animals would be much easier to catch, examine and release if a dose of tranquilliser could be administered by projection from afar. Murdoch became experienced with repairing and modifying guns during World War II, as rifles and shot guns were not being imported into New Zealand at that time. With both motive and experience, Murdoch went on to develop a range of rifles, darts and pistols, which have had an enormous impact on the treatment and study of animals around the world.

At the time Murdoch started testing his gun, the only tranquilliser drugs available were curare and alkaloids of nicotine, both of which tended to have fatal reactions in a high percentage of animals. In partnership with pharmaceutical companies, he helped develop more sophisticated drugs with precise and safe reactions.

Paxarms Limited (which stands for peace and arms), Murdoch’s own company, has developed various systems for administering veterinary products to a range of animals.


Colin Murdoch has been acknowledged for his life's work. In 1976 he won three gold medals and a bronze at the World Inventions Fair in Brussels. The New Zealand Design Council has also honoured him and in 2000 he was made an Officer of the New Zealand Order of Merit for services to inventing. Time magazine included him in a list of the 100 most influential people of the South Pacific.

Despite the relative ubiquity of his inventions, Murdoch did not become rich because of them. He deliberately chose not to sue companies that violated his patents, satisfied instead that they were being put to good use.

In his final years he lived quietly in Timaru until his death from cancer.


#11 Re: Help Me ! » Least value in decimal » 2017-06-30 23:53:17


C is the least (0.015); Second part : 0.501 is bigger of the two.

#12 Re: Formulas » Trigonometry Formulas » 2017-06-30 19:35:29


The post has been rectified.

Cos(A - B) - Cos(A + B) = 2SinASinB

#14 Re: Introductions » A name change request one more time ? » 2017-06-29 14:34:42


Since you are not a Real Member or Moderator, it isn't possible to send PM. However, Administrators can help you, with a desired username. Any of us would accede to the request gladly.

#15 Re: Dark Discussions at Cafe Infinity » crème de la crème » 2017-06-27 16:54:55

170. Adam Osborne (March 6, 1939 – March 18, 2003) was a Thailand-born British-American author, book and software publisher, and computer designer who founded several companies in the United States and elsewhere.


Osborne was known to frequent the famous Homebrew Computer Club's meetings around 1975. He was best known for creating the first commercially available portable computer, the Osborne 1, released in April 1981. It weighed 24.5 pounds (12 kg), cost US$1795 - just over half the cost of a computer from other manufacturers with comparable features - and ran the popular CP/M 2.2 operating system. It was designed to fit under an airline seat. At its peak, Osborne Computer Corporation shipped 10,000 units of "Osborne 1" per month. Osborne was one of the first personal computing pioneers to understand fully that there was a wide market of buyers who were not computing hobbyists: the Osborne 1 included word processing and spreadsheet software. This was at a time when IBM would not bundle hardware and software with their PCs, selling separately the operating systems, monitors, and even cables for the monitor.

Adam Osborne's experience in the computer industry gave his new company credibility. Osborne Computer Corporation advertisements compared Adam Osborne's influence on the personal computer market to Henry Ford's influence on transportation. It is said that in 1983, Osborne bragged about two advanced new computers his company was developing. These statements destroyed consumer demand for the Osborne 1, and the resulting inventory glut forced Osborne Computer to file for bankruptcy on September 13, 1983. This phenomenon, a pre-announcement of a new product causing a catastrophic collapse in demand for older ones, became known as the Osborne effect, but according to some new sources the real reason for Osborne Computer's bankruptcy was management errors and insufficient cash flow.


After Osborne Computer's collapse, Adam Osborne wrote a best-selling memoir of his experience, Hypergrowth: The Rise and Fall of the Osborne Computer Corporation with John C. Dvorak, which was published in 1984.


#17 Re: This is Cool » Something ineteresting » 2017-06-25 19:12:42


325 is the smallest number to be the sum of two squares in 3 different ways:


425 also has a similarly property :

#18 Re: Ganesh's Puzzles » General Quiz » 2017-06-24 15:03:38


#6645. Name the seventh President of the United States, nicknamed "Old Hickory".

#6646. Name the person (28 October 1466 – 12 July 1536), known as Erasmus or Erasmus of Rotterdam, a Dutch Renaissance humanist, Catholic priest, social critic, teacher, and theologian.

#19 Dark Discussions at Cafe Infinity » Kalam SAT » 2017-06-24 14:35:30

Replies: 0

Kalam SAT is a microsatellite, named after former Indian president Dr. A. P. J. Abdul Kalam built by an Indian High school student team for participation in the Cubes in Space, a STEM-based education program by NASA, with an objective to teach school students (ages 11-18) how to design and compete to launch an experiment into space with a free opportunity to design experiments to be launched into space on a NASA rocket or balloon if there project is selected. Kalam SAT was launched by NASA along with several other Cube SAT micro satellite from other participants on 22 June 2017 from Wallops Island.

Although Kalam SAT has been reported to be the world’s lightest satellite, the term 'lightest' probably applies more to the KickSat Sprite—which is considerably smaller, lighter, and actually flown in orbit. Due to a malfunction, KickSat Sprites never deployed from KickSat, so that KickSat 1 orbited the earth as a 5.5 Kilograms 3U CubeSat. The Sprites burned up inside KickSat during re-entry. In its first deployment, KalamSat won't actually be a satellite since it won't reach orbit; it will only fly on a sounding rocket.

The probe was built by a team of 7 people led by Rifath Sharook, an 18 year old student from Pallapatti, Tamil Nadu, India, on behalf of Space Kidz India, a Research Organisation based on Chennai, as a part of a competition, named as - ‘Cubes in Space’. This contest was jointly organised by NASA and another organisation ‘I Doodle Learning’ which is a global education company. This will be the first time that a space probe, made by an Indian student, will be launched by NASA.

The weight of the probe is just 64 grams and it is fitted in a 3.8 centimeters cube. The probe is composed of 3-D printed reinforced carbon fiber polymer. Part of the components were supplied from India and other parts from abroad. The probe will be launched by a sub-orbital spaceflight. The expected time span of the mission (post flight) is 240 minutes. The tiny probe will be operated only for less than 12 minutes to demonstrate the performance of 3-D printed carbon fiber in a micro-gravity environment of space.

#20 Re: Dark Discussions at Cafe Infinity » The amazing story of a dog » 2017-06-24 14:14:10

Hi iamaditya,

Yes, you are correct. Now, the three Administrators are MathsIsFun, bob bundy and me.

#23 Re: Introductions » having fun with math » 2017-06-17 14:15:32

Hi KenE,

Welcome to the forum! Very nice introduction!

#24 Re: Introductions » I'm a new member » 2017-06-02 16:23:21


Welcome to the forum, CesarConspirator!

#25 Re: Introductions » i am new here » 2017-05-26 23:36:25

Hi  nicole19,

Welcome to the forum!

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