Amyotrophic Lateral Sclerosis (ALS) Series-Disabled Legend Professor Stephen Hawking

Prof. Stephen Hawking was born on 8 January 1942 (300 years after the death of Galileo) in Oxford, England. Prof. Stephen Hawking parents’ house was in north London, but during the second world war Oxford was considered a safer place to have babies. When he was 8, his family moved to St Albans, a town about 20 miles north of London.

At the age of 11 Prof. Stephen Hawking went to St Albans School, and then on to University College, Oxford, his father’s old college. Prof. Stephen Hawking wanted to do Mathematics, although his father would have preferred medicine. Mathematics was not available at University College, so he did Physics instead. After 3 years and not very much work he was awarded a first class honours degree in Natural Science.

Stephen then went on to Cambridge to do research in Cosmology, there being no-one working in that area in Oxford at the time. Prof. Stephen Hawking’s supervisor was Denis Sciama, although he had hoped to get Fred Hoyle who was working in Cambridge. After gaining his Ph.D. he became first a Research Fellow, and later on a Professorial Fellow at Gonville and Caius College.

After leaving the Institute of Astronomy in 1973 Prof. Stephen Hawking came to the Department of Applied Mathematics and Theoretical Physics, and since 1979 has held the post of Lucasian Professor of Mathematics. The chair was founded in 1663 with money left in the will of the Reverend Henry Lucas, who had been the Member of Parliament for the University. It was first held by Isaac Barrow, and then in 1669 by Isaac Newton.

Prof. Stephen Hawking has worked on the basic laws which govern the universe. With Roger Penrose he showed that Einstein’s General Theory of Relativity implied space and time would have a beginning in the Big Bang and an end in black holes. These results indicated it was necessary to unify General Relativity with Quantum Theory, the other great Scientific development of the first half of the 20th Century. One consequence of such a unification that he discovered was that black holes should not be completely black, but should emit radiation and eventually evaporate and disappear. Another conjecture is that the universe has no edge or boundary in imaginary time. This would imply that the way the universe began was completely determined by the laws of science.

Prof. Stephen Hawking’s many publications include: The Large Scale Structure of Spacetime with G F R Ellis, General Relativity: An Einstein Centenary Survey, with W Israel, and 300 Years of Gravity, with W Israel. Prof. Stephen Hawking has 3 popular books published; his best seller A Brief History of Time, Black Holes and Baby Universes and Other Essays and most recently in 2001, The Universe in a Nutshell.

There are .pdf and .ps versions of his full publication list. Prof. Stephen Hawking has 12 honorary degrees, was awarded the CBE in 1982, and was made a Companion of Honour in 1989. Prof. Stephen Hawking is the recipient of many awards, medals and prizes and is a Fellow of The Royal Society and a Member of the US National Academy of Sciences.

Prof. Stephen Hawking continues to combine family life (he has three children and one grandchild), and his research into theoretical physics together with an extensive programme of travel and public lectures. Prof. Stephen Hawking suffers from ALS.

What is ALS?

ALS stands for Amyotrophic Lateral Sclerosis, sometimes called Lou Gehrig’s disease. It is a rapidly progressive and fatal neuromuscular disease that is characterized by degeneration of a select group of nerve cells and pathways (motor neurons) in the brain and spinal cord. This loss of motor neurons leads to progressive paralysis of the voluntary muscles. The heart is not a voluntary muscle, and therefore, remains unaffected by the disease. However, since breathing is controlled voluntarily by the chest muscles, death usually occurs when the chest muscles are no longer able to help the lungs achieve adequate oxygenation. Generally, there is little impairment of the brain or the senses.

“Amyotrophic” means:A = absence ofmyo = muscletrophic = nourishmentlateral = side (of spine)sclerosis = hardening or scarring ALS is not contagious, but it is fatal.For the most part, the battle is short, with 80% losing their lives within three to five years of diagnosis. While between 10% and 20% live ten years or more after diagnosis, others live only a few months. While the cause is unknown, research is being conducted in areas relating to genetic predispositions, viral or infectious agents, environmental toxins and immunological changes. For some people, the muscles for speaking, swallowing or breathing are the first to be affected. This is known as bulbar ALS.

The term “bulbar” refers to the motor neurons located in the brain stem, that control the muscles used for chewing, swallowing, and speaking. ALS symptoms, and the order in which they occur, vary from one person to another. In 85% of cases, ALS effects the lower portion of the spinal cord first. This is known as limb onset ALS. In these cases, muscle weakness, cramps and weakened reflexes affects the muscles in the arms and legs as the first signs of ALS. The rate of muscle loss can vary significantly from person to person with some patients having long periods with very slow degeneration. Signs and Symptoms Upper Motor Neuron Degeneration muscle stiffness or rigidity emotional lability (decreased ability to control emotions) excessive fatigue dysphagia (difficulty swallowing) dyspnea (shortness of breath) dysarthria (a speech disorder caused by impairment of the muscles used for speaking) incresed or ‘b risk’ reflexesgait spasticiy Lower Motor Neuron Degeneration muscle weakness and atrophy involuntary contraction of muscle fibres muscle cramps weakened reflexes flaccidity (decreased muscle tone)difficulty swallowing disordered articulation shortness of breath at rest.

Is ALS a Rare Disease?

ALS is not considered a rare disease. Approximately 2,500-3,000 Canadians currently live with ALS. 2 or 3 Canadians lose their battle to this devastating disease every day. In Ontario, roughly 1,000 people have ALS at any one time. “ALS is clearly the most common cause of neurological death on an annual basis,” Dr. Michael Strong, clinician at the University Health Sciences Centre and research scientist at the Robarts Research Institute, London, Ontario.

What Causes ALS?

We don’t really know what causes ALS, but we do know that it can strike any adult at any time. While the usual age at onset is between 45 and 65, people as young as 17 have been diagnosed in the past. Between 5 and 10% of ALS cases are found in the same families, meaning that they are “familial”, and are definitely linked genetically. But for the most part, diagnosis is sporadic and we don’t know how it is caused.

What are the early symptoms?

ALS usually becomes apparent either in the legs, the arms, the throat or the upper chest area. Some people begin to trip and fall, some may notice muscle loss in their hands and arms and some find it hard to swallow and slur their speech. ALS is difficult to diagnose. There is no specific test available that will either rule out or confirm the presence of ALS. Diagnosis is usually made through a ‘diagnosis of exclusions’. Neurologists conduct a number of tests, thereby ruling out other disorders that may cause similar symptoms, such as strokes or multiple sclerosis and if nothing else is positive and yet the symptoms continue to worsen, ALS is often the reason.

What are the effects of ALS?

Because ALS frequently takes its toll before being positively diagnosed, many patients are debilitated before learning they have ALS. The disease usually does not affect the senses – taste, touch, sight, smell, and hearing – or the mind. ALS has a devastating effect on patients and their families. As they cope with the prospect of advancing disability and eventually death, it consumes their financial and emotional reserves. It is a costly disease in its later stages, demanding both extensive nursing care and expensive equipment.

What can be done about ALS?

There is no known cure at this time and very little in the way of treatment that will have an effect on the disease itself.

Is there hope for people with ALS?

Research is looking to find not only the cause of the disease so that a cure can be developed but also other medications or treatments that can help until a cure is found. With improved knowledge about ALS, healthcare providers and families can help people living with ALS live life more fully. The services offered by the ALS Society of Ontario help improve the quality of life for those who live with ALS and their families.

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Hearing Impairment Series-Disabled Legend Guillaume Amontons

Guillaume Amontons was born on 31 August, 1663 in Paris, France and died on 11 October, 1705 in Paris, France. Guillaume was a French scientific instrument inventor and physicist. Guillaume was one of the pioneers in tribology, apart from Leonardo da Vinci, John Theophilius Desanguliers, Leonard Euler and Charles-Augustin de Coulomb.

Guillaume’s father was a lawyer from Normandy who had moved to the French capital. While still young, Guillaume lost his hearing, which may have motivated him to focus entirely on science. Guillaume never attended a university, but was able to study mathematics, the physical sciences, and celestial mechanics. Guillaume also spent time studying the skills of drawing, surveying, and architecture. Guillaume was supported in his research career by the government, and was employed in various public works projects.

Among his contributions to scientific instrumentation were improvements to the barometer (1695), hygrometer (1687), and thermometer (1695), particularly for use of these instruments at sea. Guillaume also demonstrated an optical telegraph and proposed the use of his clepsydra (water clock) for keeping time on a ship at sea.

Guillaume investigated the relationship between pressure and temperature in gases though he lacked accurate and precise thermometers. Though his results were at best semi-quantitative, he established that the pressure of a gas increases by roughly 1/3 between the temperatures of cold and the boiling point of water. This was a substantial step towards the subsequent gas laws and, in particular, Charles’s law.

Guillaume’s work led him to speculate that a sufficient reduction in temperature would lead to the disappearance of pressure. Thus, he is the first researcher to discuss the concept of an absolute zero of temperature, a concept later extended and rationalised by William Thomson, 1st Baron Kelvin. In 1699, Guillaume published his rediscovery of the laws of friction first put forward by Leonardo da Vinci. Though they were received with some scepticism, the laws were verified by Charles-Augustin de Coulomb in 1781.

Leonardo da Vinci (1452-1519)) can be named as the father of modern tribology as he studied an incredible manifold of tribological subtopics such as: friction, wear, bearing materials, plain bearings, lubrication systems, gears, screw-jacks, and rolling-element bearings. 150 years before Guillaume’s Laws of Friction were introduced, he had already recorded them in his manuscripts. Hidden or lost for centuries, Leonardo da Vinci’s manuscripts were read in Spain a quarter of a millennium later.

Guillaume’s Laws of Friction were first recorded in books during the late 17th century.

There 3 laws of friction are:

  • 1. The force of friction is directly proportional to the applied load. (Guillaume’s 1st Law)
  • 2. The force of friction is independent of the apparent area of contact. (Guillaume’s 2nd Law)
  • 3. Kinetic friction is independent of the sliding velocity. (Coulomb’s Law)

NOTE: These 3 laws only apply to dry friction, in which the addition of a lubricant modifies the tribological properties signifiantly.

By looking at any surface on the microscopic level, one would find that it is never perfectly flat. There would exist many tiny bumps and craters, due to imperfections on the surface and the alignment of molecules. (The skin does not feel the bumps and craters because they are too small to be detected.) Considering a smooth stone on a smooth flat road, the 2 surfaces would be still in contact, but only at a few points (the bumps do fot fit exactly into the craters). Due to electrostatic forces of repulsion between the atoms (nuclei and nuclei) of the stone and the road, the road will exert a force on the stone, and the stone will exert a force on the road (normal contact forces). The NET force exerted on the stone would be the NORMAL contact force.

If net external forces cause the stone to move to the RIGHT, the forces that the road exert on the stone would be slightly skewed to the LEFT, thus the net force will be pointing UP but LEFTWARD (tilted contact force). As the vertical component of the net force is the normal contact force, the extra horizontal leftward component of the force would therefore be the FRICTIONAL force. (Note: friction OPPOSES motion)

Suppose the stone had a greater mass (hence greater weight as g=constant). The stone would then:

  • exert a greater force on the road (the increased load causes the separation distance of the nuclei to decrease, force of repulsion becomes stronger(inverse-square law) ), AND
  • more of the atoms of the road and the stone would be in contact.

Hence, when the stone is moved, a greater frictional force would be produced (more areas of contact means that more forces can be skewed, producing more horizontal components of the contact forces).

Guillaume’s law applies to any 2 surfaces, regardless of their orientation. (e.g. pressing a brick against the ceiling, etc.)

NOTE: Applied load means the normal contact force acting on the stone. That is, if the stone is being pushed down harder while it was trying to move, the force acting on the ground increases, and hence the force of the ground acting on the stone (normal contact) increases. This means that more force is required to move the stone across the ground. (frictional force increase)

What this law means is that if two equal masses made of similar material are resting on the same surface with DIFFERENT SURFACES AREAS OF CONTACT, they would require the SAME AMOUNT of FORCE to start moving (overcome static friction) and to move at constant speed+.

To put it in another way: considering 2 equal masses, and the area in contact in situation A is greater than in situation B. This only means that in situation A, the load is distributed across a greater area then in situation B. However, the applied load is still the same! Thus to move both masses, we would require the same amount of applied force to overcome friction. (Guillaume’s First Law)

+ To maintain constant speed, net force has to be 0N. Assuming no drag forces,
 \begin{align} F_{applied}-F_{fric} & = 0 \\ \therefore F_{applied} & = F_{fric} \\ \end{align}

Through studies and experimental observations on the properties of friction, a relationship between frictional force and normal contact force was established:

\begin{align}F_{fric}=\mu N\end{align},

where μ is the coefficient of friction and N is the normal contact force.

This is as predicted by Guillaume’s 2 laws, where Ffric depends only on the normal contact force (reaction pair of the applied load), and is independent of the surface area in contact.

However, exceptions to Guillaume’s Law have been observed in various nanometric scenarios. For example, when 2 surfaces get close enough such that molecular interactions and atomic forces come into play, the 2 surfaces are attracted together and form what was known as ‘negative load’.

*requires verfication by Specialists*

Honours:

  • Member, Académie des Sciences, (1690)
  • The Amontons crater on the Moon is named after him.

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Hearing Impairment Series-Disabled Legend Oliver Heaviside

Oliver Heaviside was born on 18 May, 1850 in London’s Camden Town and died on 3 February, 1925 at Torquay in Devon, and is buried in Paignton cemetery. Most of his recognition was gained posthumously.

Oliver Heaviside was a self-taught English electrical engineer, mathematician and physicist who adapted complex numbers to the study of electrical circuits, invented mathematical techniques to the solution of differential equations (later found to be equivalent to Laplace transforms), reformulated Maxwell’s field equations in terms of electric and magnetic forces and energy flux, and independently co-formulated vector analysis. Although at odds with the scientific establishment for most of his life, Oliver Heaviside changed the face of mathematics and science for years to come.

Oliver Heaviside was short and red-headed, and suffered from scarlet fever during his youth. The illness had a lasting impact on him, and Oliver Heaviside was left partially deaf. Oliver Heaviside was a good scholar (placed 5th out of 500 students in 1865). Oliver Heaviside left school at the age of 16 and to study at home in the subjects of telegraphy and electromagnetism. Oliver Heaviside’s uncle Sir Charles Wheatstone (1802-1875) was the original co-inventor of the telegraph back in the mid 1830s. Sir Charles Wheatstone was married to Oliver Heaviside’s mother’s sister in London. During the early decades of Oliver Heaviside’s life his uncle was an internationally celebrated expert in telegraphy and electromagnetism.

Between the age of 16 and 18 he studied at home. Then—in the only paid employment he ever had—he took a job as a telegraph operator with the Great Northern Telegraph Company, working in Denmark and then in Newcastle upon Tyne, and was soon made a chief operator. Oliver Heaviside’s uncle’s connections probably helped him get this job. Oliver Heaviside continued to study and at the age of 21 and 22 he published some research related to electric circuits and telegraphy. In 1874 at the age of 24 Oliver Heaviside quit his job to study full-time on his own at his parents’ home in London.

Subsequently, Oliver Heaviside did not have a regular job. Oliver Heaviside remained single throughout his life.

In 1873 Oliver Heaviside had encountered James Clerk Maxwell’s just published, and today famous, 2-volume Treatise on Electricity and Magnetism. In his old age Oliver Heaviside recalled:

“I remember my first look at the great treatise of Maxwell’s when I was a young man… I saw that it was great, greater and greatest, with prodigious possibilities in its power… I was determined to master the book and set to work. I was very ignorant. I had no knowledge of mathematical analysis (having learned only school algebra and trigonometry which I had largely forgotten) and thus my work was laid out for me. It took me several years before I could understand as much as I possibly could. Then I set Maxwell aside and followed my own course. And I progressed much more quickly… It will be understood that I preach the gospel according to my interpretation of Maxwell.”

Doing full-time research from home, he helped develop transmission line theory (also known as the “telegrapher’s equations”). Oliver Heaviside showed mathematically that uniformly distributed inductance in a telegraph line would diminish both attenuation and distortion, and that, if the inductance were great enough and the insulation resistance not too high, the circuit would be distortionless while currents of all frequencies would be equally attenuated. Oliver Heaviside’s equations helped further the implementation of the telegraph.

In 1880, Oliver Heaviside researched the skin effect in telegraph transmission lines. In 1884 he recast Maxwell’s mathematical analysis from its original cumbersome form (they had already been recast as quaternions) to its modern vector terminology, thereby reducing the original 20 equations in 20 unknowns down to the 4 differential equations in 2 unknowns we now know as Maxwell’s equations. The 4 re-formulated Maxwell’s equations describe the nature of static and moving electric charges and magnetic dipoles, and the relationship between the 2, namely electromagnetic induction. In 1880 he patented, in England, the co-axial Cable.

Between 1880 and 1887, Oliver Heaviside developed the operational calculus (involving the D notation for the differential operator, which he is credited with creating), a method of solving differential equations by transforming them into ordinary algebraic equations which caused a great deal of controversy when first introduced, owing to the lack of rigor in his derivation of it. Oliver Heaviside famously said, “Mathematics is an experimental science, and definitions do not come first, but later on.” Oliver Heaviside was replying to criticism over his use of operators that were not clearly defined. On another occasion he stated somewhat more defensively, “I do not refuse my dinner simply because I do not understand the process of digestion.”

In 1887, Oliver Heaviside proposed that induction coils (inductors) should be added to telephone and telegraph lines to increase their self-induction in and correct the distortion from which they suffered. For political reasons, this was not done. The importance of Oliver Heaviside’s work remained undiscovered for some time after publication in The Electrician, and so its rights lay in the public domain. AT&T later employed one of its own scientists, George A. Campbell, and an external investigator Michael I. Pupin to determine whether Oliver Heaviside’s work was incomplete or incorrect in any way. Campbell and Pupin extended Oliver Heaviside’s work, and AT&T filed for patents covering not only their research, but also the technical method of constructing the coils previously invented by Oliver Heaviside. AT&T later offered Oliver Heaviside money in exchange for his rights; it is possible that the Bell engineers’ respect for Oliver Heaviside influenced this offer. However, Oliver Heaviside refused the offer, declining to accept any money unless the company were to give him full recognition. Oliver Heaviside was chronically poor, making his refusal of the offer even more striking.

In 2 papers of 1888 and 1889, Oliver Heaviside calculated the deformations of electric and magnetic fields surrounding a moving charge, as well as the effects of it entering a denser medium. This included a prediction of what is now known as Cherenkov radiation, and inspired Fitzgerald to suggest what now is known as the Lorentz-Fitzgerald contraction.

In the late 1880s and early 1890s, Oliver Heaviside worked on the concept of electromagnetic mass. Oliver Heaviside treated this as “real” as material mass, capable of producing the same effects. Wilhelm Wien later verified Oliver Heaviside’s expression (for low velocities).

In 1891 the British Royal Society recognized Oliver Heaviside’s contributions to the mathematical description of electromagnetic phenomena by naming him a Fellow of the Royal Society. In 1905 Oliver Heaviside was given an honorary doctorate by the University of Göttingen.

In 1902, Oliver Heaviside proposed the existence of the Kennelly-Heaviside Layer of the ionosphere which bears his name. Oliver Heaviside’s proposal included means by which radio signals are transmitted around the earth’s curvature. The existence of the ionosphere was confirmed in 1923. The predictions by Oliver Heaviside, combined with Planck’s radiation theory, probably discouraged further attempts to detect radio waves from the Sun and other astronomical objects. For whatever reason, there seem to have been no attempts for 30 years, until Jansky’s development of radio astronomy in 1932.

In later years his behavior became quite eccentric. Though he had been an active cyclist in his youth, his health seriously declined in his 6th decade. During this time Oliver Heaviside would sign letters with the initials “W.O.R.M.” after his name though the letters did not stand for anything. Oliver Heaviside also reportedly started painting his fingernails pink and had granite blocks moved into his house for furniture.

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Dyslexia Series-Disabled Legend Albert Einstein

Albert Einstein was born on 14 March, 1879 and died on 18 April, 1955. Being one of the most important great minds of his century Albert Einstein was then known to suffer from dyslexia mainly because of his bad memory and his constant failure to memorize the simplest of things.

Albert would not remember the months in the year yet he would succeed in solving some of the most complicated mathematical formulas of the time without any trouble. Albert may have never learned how to properly tie his shoelaces but his scientific contributions and theories still have a major effect on all of todays current knowledge of science.

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