Instruct: Given a question, retrieve relevant passages that can help answer the question.
Query: Who invented MRI technology?
Damadian is the company's largest shareholder, with 8% of stock worth $6.5 million. Despite owning only 8% of the stock, he maintains almost 100% control of the company through a separate class of shares (Class C) that only Damadian controls 2007. Damadian later collaborated with Wilson Greatbatch, one early developer of the implantable pacemaker, to develop an MRI-compatible pacemaker. He invented a stand-up MRI system and has 15 MRI scanning centers across the United States. There are a number of independent MRI centers that use this technology both in the U.S. and around the world. The company conceived and built the world's first Upright Multi-Positional MRI, which was recognized as The Invention of the Year in 2007 by the Intellectual Properties Owners Association Education Foundation.
The portable version of the defibrillator was invented in the mid-1960s by Frank Pantridge in Belfast, Northern Ireland.
In 1945, the specific heating effect of a high-power microwave beam was accidentally discovered by Percy Spencer, an American self-taught engineer from Howland, Maine. Employed by Raytheon at the time, he noticed that microwaves from an active radar set he was working on started to melt a chocolate bar he had in his pocket. The first food deliberately cooked with Spencer's microwave was popcorn, and the second was an egg, which exploded in the face of one of the experimenters. To verify his finding, Spencer created a high density electromagnetic field by feeding microwave power from a magnetron into a metal box from which it had no way to escape. When food was placed in the box with the microwave energy, the temperature of the food rose rapidly. On 8 October 1945, Raytheon filed a United States patent application for Spencer's microwave cooking process, and an oven that heated food using microwave energy from a magnetron was soon placed in a Boston restaurant for testing.
Magnetic Resonance Imaging (MRI) scans provide an image of the soft tissues in the body using radio waves and strong magnets. MRI can be used instead of CT if the patient exhibits an allergy to the contrast media administered for the test. Sometimes prior to the MRI scan, an intravenous injection of a contrasting material called gadolinium is given to allow for a more detailed image. Patients on dialysis or those who have renal insufficiency should avoid this contrasting material as it may induce a rare, yet severe, side effect known as nephrogenic systemic fibrosis. A bone scan or brain imaging is not routinely performed unless signs or symptoms suggest potential metastatic involvement of these areas.
MRI scans should also be considered to evaluate tumour extension which has grown in major blood vessels, including the vena cava, in the abdomen. MRI can be used to observe the possible spread of cancer to the brain or spinal cord should the patient present symptoms that suggest this might be the case.
On 8 May 2012, he appeared on the Radio Four series "The Life Scientific", talking to Jim al-Khalili about the Gaia hypothesis. On the program, he mentioned how his ideas had been received by various people, including Jonathan Porritt. He also mentioned how he had a claim for inventing the microwave oven. He later explained this claim in an interview with "The Manchester Magazine". Lovelock said that he did create an instrument during his time studying causes of damage to living cells and tissue, which had, according to him, "almost everything you would expect in an ordinary microwave oven". He invented the instrument for the purpose of heating up frozen hamsters in a way that caused less suffering to the animals, as opposed to the traditional way which involved putting red hot spoons on the animals' chest to heat them up. He believes that at the time, nobody had gone that far and made an embodiment of an actual microwave oven. However, he does not claim to have been the first person to have the idea of using microwaves for cooking.
Notable German physicists before the 20th century include Hermann von Helmholtz, Joseph von Fraunhofer and Gabriel Daniel Fahrenheit, among others. Albert Einstein introduced the special relativity and general relativity theories for light and gravity in 1905 and 1915 respectively. Along with Max Planck, he was instrumental in the introduction of quantum mechanics, in which Werner Heisenberg and Max Born later made major contributions. Wilhelm Röntgen discovered X-rays. Otto Hahn was a pioneer in the fields of radiochemistry and discovered nuclear fission, while Ferdinand Cohn and Robert Koch were founders of microbiology. Numerous mathematicians were born in Germany, including Carl Friedrich Gauss, David Hilbert, Bernhard Riemann, Gottfried Leibniz, Karl Weierstrass, Hermann Weyl, Felix Klein and Emmy Noether.
The development of radar, mainly in secrecy, before and during World War 2, resulted in the technological advances which made microwaves practical. Radar antennas small enough to fit on aircraft which had a narrow enough beamwidth to localize enemy aircraft required wavelengths in the centimeter range. It was found that conventional transmission lines used to carry radio waves had excessive power losses at microwave frequencies, and George Southworth at Bell Labs and Wilmer Barrow at MIT independently invented waveguide in 1936. Barrow invented the horn antenna in 1938 as a means to efficiently radiate microwaves into or out of a waveguide. In a microwave receiver, a nonlinear component was needed that would act as a detector and mixer at these frequencies, as vacuum tubes had too much capacitance. To fill this need researchers resurrected an obsolete technology, the point contact crystal detector (cat whisker detector) which was used as a demodulator in crystal radios around the turn of the century before vacuum tube receivers. The low capacitance of semiconductor junctions allowed them to function at microwave frequencies. The first modern silicon and germanium diodes were developed as microwave detectors in the 1930s, and the principles of semiconductor physics learned during their development led to semiconductor electronics after the war.
Sumio Iijima (飯島 澄男 "Iijima Sumio", born May 2, 1939) is a Japanese physicist, often cited as the inventor of carbon nanotubes. Although carbon nanotubes had been observed prior to his "invention", Iijima's 1991 paper generated unprecedented interest in the carbon nanostructures and has since fueled intense research in the area of nanotechnology.
The carbon microphone was independently developed around 1878 by David Edward Hughes in England and Emile Berliner and Thomas Edison in the US. Although Edison was awarded the first patent in mid-1877, Hughes had demonstrated his working device in front of many witnesses some years earlier, and most historians credit him with its invention.
She was named in honor of Reginald Aubrey Fessenden, born in Brome County, Quebec, Canada, 6 October 1866. He served as head chemist with Thomas Edison's East Orange, New Jersey, laboratories. In 1890 he began concentrating on electrical engineering, and through the next years made many important inventions and improvements in existing devices. His great contributions in the field of radio (particularly the invention of radio-telephony were of marked benefit not only to the Navy but to all seamen. He died 22 July 1932, at his home on Bermuda.
The first use of an external defibrillator on a human was in 1947 by Claude Beck. The portable version of the defibrillator was invented in the mid-1960s by Frank Pantridge in Belfast, Northern Ireland, a pioneer in emergency medical treatment.
In August 1961, at the International Congress of Biochemistry in Moscow, Nirenberg presented his paper. The experimentation with synthetic RNA in a cell-free system was a key technical innovation. In 1961, when they announced their methods for decoding the relationship of mRNA to amino acids, there was still a lot of experimentation required before the entire code was deciphered. The scientists had to determine which bases made up each codon, then determine the sequence of bases in the codons. This proved to be a tremendous amount of work.
The use of ultrasound in medicine was pioneered by Donald, first at Glasgow Royal Maternity Hospital and subsequently at Glasgow's new maternity hospital, the Queen Mother's Hospital (QMH), which opened in 1964. Developments in ultrasound complemented Whitfield's own research interests in fetal medicine but was still regarded with scepticism in some quarters. Whitfield had more success in gaining acceptance for obstetric ultrasound than Donald himself, who was sometimes viewed as an obsessive eccentric. As he recalled, "an honorary attachment with Professor Donald in Glasgow in 1964 had convinced me that obstetric ultrasound did have a future, but later in that year in America I was told it was just a dream of a mad, red-headed Scotsman, so I should forget it! I was told confidentially, nothing, no good will come of it, but of course that was wrong".
Germany has a long heritage of using electromagnetic waves for detecting objects. In 1888, Heinrich Hertz, who first demonstrated the existence of these waves, also noted that they, like light, were reflected by metal surfaces. In 1904, Christian Hülsmeyer obtained German and foreign patents for an apparatus, the "Telemobilskop", using a "spark gap transmitter" that could detect ships and prevent collisions; this is often cited as the first radar, but, without directly providing range, it does not qualify for this classification. With the advent of the radio tube and electronics, other detection-only systems were developed, but all used continuous waves and could not measure distance.
In 1933, physicist Rudolf Kühnhold, Scientific Director at the "Kriegsmarine" (German Navy) "Nachrichtenmittel-Versuchsanstalt" (NVA—Experimental Institute of Communication Systems) in Kiel, initiated experiments in the microwave region to measure the distance to a target. For the transmitter, he obtained assistance from two radio amateur operators, Paul-Günther Erbslöh and Hans-Karl Freiherr von Willisen. In January 1934, they formed at Berlin-Oberschöneweide the company "Gesellschaft für Elektroakustische und Mechanische Apparate" (GEMA) for this work.
Wilhelm Röntgen discovered and named X-rays. After experimenting with high voltages applied to an evacuated tube on 8 November 1895, he noticed a fluorescence on a nearby plate of coated glass. In one month, he discovered X-rays' main properties.
Magnetic fields are widely used throughout modern technology, particularly in electrical engineering and electromechanics. Rotating magnetic fields are used in both electric motors and generators. The interaction of magnetic fields in electric devices such as transformers is studied in the discipline of magnetic circuits. Magnetic forces give information about the charge carriers in a material through the Hall effect. The Earth produces its own magnetic field, which shields the Earth's ozone layer from the solar wind and is important in navigation using a compass.
Although magnets and magnetism were studied much earlier, the research of magnetic fields began in 1269 when French scholar Petrus Peregrinus de Maricourt mapped out the magnetic field on the surface of a spherical magnet using iron needles. Noting that the resulting field lines crossed at two points he named those points 'poles' in analogy to Earth's poles. He also clearly articulated the principle that magnets always have both a north and south pole, no matter how finely one slices them.
Discovered by Michael Faraday in 1845, the Faraday effect was the first experimental evidence that light and electromagnetism are related. The theoretical basis of electromagnetic radiation (which includes visible light) was completed by James Clerk Maxwell in the 1860s and 1870s. This effect occurs in most optically transparent dielectric materials (including liquids) under the influence of magnetic fields.
The prediction that light represented a transmission of energy in wave form through a "luminiferous ether", and the seeming confirmation of that prediction with Helmholtz student Heinrich Hertz's 1888 detection of electromagnetic radiation, was a major triumph for physical theory and raised the possibility that even more fundamental theories based on the field could soon be developed. Experimental confirmation of Maxwell's theory was provided by Hertz, who generated and detected electric waves in 1886 and verified their properties, at the same time foreshadowing their application in radio, television, and other devices. In 1887, Heinrich Hertz discovered the photoelectric effect. Research on the electromagnetic waves began soon after, with many scientists and inventors conducting experiments on their properties. In the mid to late 1890s Guglielmo Marconi developed a radio wave based wireless telegraphy system (see invention of radio).
In 1874, German scientist Karl Ferdinand Braun discovered the "unilateral conduction" across a contact between a metal and a mineral. Indian scientist Jagadish Chandra Bose was the first to use a crystal for detecting radio waves in 1894. The crystal detector was developed into a practical device for wireless telegraphy by Greenleaf Whittier Pickard, who invented a silicon crystal detector in 1903 and received a patent for it on November 20, 1906. Other experimenters tried a variety of other minerals as detectors. Semiconductor principles were unknown to the developers of these early rectifiers. During the 1930s understanding of physics advanced and in the mid 1930s researchers at Bell Telephone Laboratories recognized the potential of the crystal detector for application in microwave technology. Researchers at Bell Labs, Western Electric, MIT, Purdue and in the UK intensively developed point-contact diodes ("crystal rectifiers" or "crystal diodes") during World War II for application in radar. After World War II, AT&T used these in their microwave towers that criss-crossed the United States, and many radar sets use them even in the 21st century. In 1946, Sylvania began offering the 1N34 crystal diode. During the early 1950s, junction diodes were developed.
In addition to the telegraph, Morse invented a marble-cutting machine that could carve three-dimensional sculptures in marble or stone. He could not patent it, however, because of an existing 1820 Thomas Blanchard design.
The use of ultrasonography in medicine soon followed in different locations around the world. In the mid-1950s more research was undertaken by Professor Ian Donald et al., in Glasgow, which advanced the practical technology and applications of ultrasound. In 1963, in France, Léandre Pourcelot started on his thesis, which was presented in 1964, and used pulsed Doppler for blood flow calculation as its subject. This was followed up by Peronneau in 1969. Dr. Gene Strandness and the bio-engineering group at the University of Washington who conducted research on Doppler ultrasound as a diagnostic tool for vascular disease, published their first work in 1967. The first report published about the venous system appeared around 1967–1968.
GEC also funded some of the development of Magnetic Resonance Imaging (MRI) using resistive magnet technology. At the same time, EMI Medical who had introduced the CT Scanner some time before using the principle of Godfrey Hounsfield, for which he won the 1979 Nobel Prize for Physiology or Medicine, were developing MRI using cryogenic magnets - which gave a higher field strength. At the time the maximum field strength with a resistive magnet was about 0.1T. With a cryogenic magnet, 1.0 T was easily achieved. EMI Medical went bankrupt at around this time so their interests in MRI were bought by GEC. This was a major impetus for GEC's acquisition of Picker Corporation in 1981.
FLASH MRI was invented in 1985 by Jens Frahm, Axel Haase, W Hänicke, KD Merboldt, and D Matthaei (German Patent Application P 35 04 734.8, February 12, 1985) at the Max-Planck-Institut für biophysikalische Chemie in Göttingen, Germany. The technique is revolutionary in shortening MRI measuring times by up to two orders of magnitude.
In 1983, Pettigrew undertook a position as clinical research scientist at Picker International, Inc., where he began work in developing nuclear magnetic resonance imaging, later called MRI, specifically for the heart. Picker was the first company to manufacture an MRI scanner, and Pettigrew helped develop their technology for cardiovascular imaging. Of the first 10 Picker MRI scanners installed worldwide, Pettigrew co-developed, along with A.V. Lakshminarayanan, and installed the cardiac imaging software on all of these systems. These included the first units at the Mayo Clinic, Wake Forrest University, and the NIH Clinical Center and several systems in Europe.
In 1980, Paul joined the GE Research Center in Schenectady NY. They ordered the biggest magnet available – a 1.5 Tesla system – and built the first high-field whole-body MRI/MRS scanner, overcoming problems of coil design, RF penetration and signal-to-noise. The results translated into the highly successful 1.5 Tesla clinical MRI products of which there are well over 20,000 systems today, representing 60-70% of all systems. Paul did the first localized MRS in human heart and brain. After starting a collaboration on heart applications with Robert Weiss at Johns Hopkins, Paul returned to Johns Hopkins University in 1994, as Professor and Director of the MR Research Division. He works on the application of MRS to measure cardiac energy metabolism in the healthy and failing heart, and the development of interventional MRI technology. He has about 200 peer-reviewed papers with most-cited reviews of tissue relaxation in Medical Physics, and ~50 patents, including high-field MRI (>0.7 Tesla), spin-echo MRI, ‘crusher’ gradients, 'fat-saturation', '3D-slab' MRI, and 'point resolved spectroscopy' (PRESS), 2D spatially-selective pulses, MRI-safe implantable leads (licensed and sold as Avista™ by Boston Scientific Inc), and 'MRI endoscopy'. He is an ISMRM Fellow, 1989 Gold Medal recipient, a GE gold patent and Coolidge Fellowship awardee, and 2015 Gold Medal recipient of the American Roentgen-Ray Society.