SCIENCE with Ms Lun
Today in Science
August
4 August : Dame Charmian Jocelyn O'CONNOR (nee Bishop)
born 1937 - present
New Zealand physical organic chemist and was the first female professor of chemistry at Auckland University in 1986. She has authored (or co-authored) over 300 scientific papers. Her field of research was looking at he reactions of biologically active compounds, mainly looking at the mechanisms (trying to understand each step in the reaction) and kinetics (rates of reactions). She was made a Dame in 2018.
4 August : Nicolas-Jacques CONTE
born 1755 - died 6 December 1805 (aged 50)
This French mechanical genius invented the pencil. France was unable to import graphite from England for writing/drawing due to a blockade. Conté mixed powdered graphite with clay and pressed the material between two half-cylinders of wood. Thus the modern pencil was formed. He lost his left eye in a laboratory accident.
6th August. Sir Alexander FLEMING. Born 1881. Died 11 Mar 1955, aged
What: Scottish-born medical doctor
Famous for: discovering penicillin (antibiotic) and winning the 1945 Nobel Prize for Medicine or Physiology.
Fleming moved to London at age 13 and lived with his brother, a medical doctor. Fleming studied business and commerce at the Polytechnic school. He was a bright student and was soon moved into classes with 16 year olds. He worked in a shipping office, a job he did not enjoy. After inheriting some money from an uncle at age 20, he decided to attend medical school - he passed all his entrance exams and was the top student in all the UK. In 1903, he graduated from St Mary's Hospital Medical school with distinction. He continued his studies and in 1908, he graduated as the top student in bacteriology.
In 1914, Fleming enlisted in the army. As a captain in the Royal Army Medical Corps working in field hospitals in France, he discovered the antiseptic agents used to prevent infection and treat wounds were actually killing more soldiers than the infections themselves, especially in deep wounds.
Fleming also discovered an important enzyme called lysozyme which plays an important role in our bodies to help fight bacterial infections.
The discovery of penicillin
In 1928, Fleming was a Professor of Bacteriology at St Mary's hospital in London. On September 3, he returned from holiday and was sorting through petri dishes that were growing colonies of Staphylococcus (which can cause boils, sore throats and wound infections). He noticed one agar plate had a mould colony growing on it along with Staphylococcus colonies. However, around the mould was a clear zone, indicating that the mould had secreted something that inhibited the growth of the bacteria. This mould was later identified as a rare strain of the mould Penicillium notatum and the mould juice contained antibacterial properties, later identified as penicillin.
The discovery of penicillin was revolutionary - patients no longer had to suffer, hope and wait or die from simple infections such as rheumatic fever, pneumonia and blood poisoning. However, it wasn't until the 1940s when penicillin was able to be produced in large-scale quantities by pharmaceutical companies.
Penicillium chrysogenum (previously called P. notatum) is growing int he middle of the agar plate. Around the outside are colonies of bacteria. Note the zone of inhibition around the fungus where the bacteria have failed to grow.
13 August, 1814 : Anders Jonas Ångström. Died: June 21, 1874
What: Swedish physicist
Known for: founding spectroscopy (the branch of science concerned with the investigation and
measurement of spectra produced when matter interacts with or emits electromagnetic radiation.)
Angstrom (Å), a unit of length, equal to 0.1 nanometre, is named after Angstrom and mainly used
to when measuring wavelengths of light i.e. visible light is 4000 - 7000 Å.
Ångström also studied thermal (heat) conductivity and showed it was proportional to
electrical conductivity.
In 1862, he made the discovery that hydrogen was present in the sun's atmosphere.
In 1867, he was the first to study the spectrum of the aurora borealis (Northern lights) and discovered oxygen is responsible for the yellow-green colour at 5577Å.
Ångström & Robert Thalén measured on the spectral lines of many elements and these are still used today.
Spectral lines
Each element emits a different spectral image like a unique fingerprint. There are two types of spectral lines: emission (the light emitted by the element) and absorption (the light absorbed by the element) . These lines can be used to deduce which elements are present in star, galaxy or a cloud of interstellar gas.
The emission spectra of some common elements.
19 August : Sir Paul Terence CALLAGHAN Born 1947. Died 24 Mar 2012
What: New Zealand physicist
Known for: nanotechnology and magnetic resonance.
After graduating from Victoria University, Wellington, Callaghan did his PhD at Oxford University. He studied nuclear magnetic resonance (NMR) and did further investigations on his return to NZ at Massey University (Palmerston North) by using a spectrometer to apply NMR to study materials at molecular level without destroying them.
in the early 2000s, Callaghan left Massey and became the founding director of the MacDiarmid Institute for Advanced Materials and Nanotechnology (his aim was to gather a multi-disciplinary group of minds that could compete with the best institutes in the world).
The Callaghan Innovation is a government run R & D organisation, set up in Feb 2013. It's aim is to partner with businesses to commercialise scientific research and to build New Zealand’s innovation capability and contribute to growing our innovation economy.
Sir Paul Callaghan received his knighthood in 2009.
28th : Sir Godrey Newbold HOUNSFIELD. Born 1919. Died 12 August 2004.
What: English electrical engineer
Known for: inventing CAT (computerised axial tomography) scans.
Awards/honours: 1979 - Nobel Prize for Physiology or Medicine (shared jointly with Allan M Cormack, also for CAT work)
1981 - received knighthood.
Growing up on farm, Hounsfield was fascinated by mechanical and electrical gadgets. In his teenage years, he experimented on the farm, almost blowing himself up! At school, he was only interested in physics and maths. He joined the RAF just before WWII and studied books for radio mechanics. He enjoyed building his own equipment and this skill was noticed by Air Vice-Marshal Cassidy, who got a scholarship for Hounsfield to enable him to study at the Faraday House Electrical Engineering College in London at the end of the war.
In 1951, Hounsfield joined EMI and remained there until his retirement in 1986. In 1967, while out walking, he realised the contents of a box could be reconstructed by taking readings at all angles. He scanned the brain using hundreds of X-ray beams at cross-sections. These were reconstructed by a computer program using complex algebraic calculations.
The Hounsfield unit (HU) is a measure of radiodensity still used today in CT scans.
29 August : International Day against Nuclear tests (UN)
This day is important for increasing awareness and education “about the effects of nuclear weapon test explosions or any other nuclear explosions and the need for their cessation as one of the means of achieving the goal of a nuclear-weapon-free world.”
30th : Sir Ernest RUTHERFORD. Born 1871. Died 19 October, 1937.
What: NZ born physicist
Known for: splitting the atom
Awards/honours: 1908 - Nobel Prize for Chemistry "for his investigations into the disintegration of the elements, and the chemistry of radioactive substances."
1914 - received knighthood
1925 - became Baron Rutherford of Nelson.
Rutherford was born in Nelson, NZ and was one of 12 children. His parents brought the children up saying "We haven't the money, so we've got to think" and making sure they had a good education.
Rutherford gained three degrees at Canterbury College (now Canterbury University) and gained a scholarship to study at the University of Cambridge.
In 1898, he became a professor at McGill University in Montreal, Canada and discovered his first career breakthrough - atoms of heavy metals have a tendency to decay.
In 1907, he returned to England taking up the role of professor of physics at Manchester University and had his second breakthrough - a new model of the atom as a tiny nucleus surrounded by orbiting electrons (called the Rutherford model).
In 1917, Rutherford had his third breakthrough - spitting the atom.
In 1925, he returned to NZ for the final time and his call for the government to support education and research helped establish the DSIR (Department of Scientific and Industrial Research) in 1926.
Rutherford said during WWI, he hoped no one would discover how to extract the energy of the atom until man was 'living at peace with his neighbours'. Two years after his death from a strangulated hernia, nuclear fission was discovered by Otto Hahn, one of Rutherford's students in Montreal. Rutherford is buried at Westminster Abbey and has an element, Rutherfordium, named after him.