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History of radio

The early history of radio is the history of technology that produces and uses radio instruments that use radio waves. Within the timeline of radio, many people contributed. Radio development began as "wireless telegraphy". Radio history involves matters of broadcasting; the idea of wireless communication predates the discovery of "radio" with experiments in "wireless telegraphy" via inductive and capacitive induction and transmission through the ground and train tracks from the 1830s on. James Clerk Maxwell showed in theoretical and mathematical form in 1864 that electromagnetic waves could propagate through free space, it is that the first intentional transmission of a signal by means of electromagnetic waves was performed in an experiment by David Edward Hughes around 1880, although this was considered to be induction at the time. In 1888 Heinrich Rudolf Hertz was able to conclusively prove transmitted airborne electromagnetic waves in an experiment confirming Maxwell's theory of electromagnetism.

After the discovery of these "Hertzian waves" many scientists and inventors experimented with wireless transmission, some trying to develop a system of communication, some intentionally using these new Hertzian waves, some not. Maxwell's theory showing that light and Hertzian electromagnetic waves were the same phenomenon at different wavelengths led "Maxwellian" scientists such as John Perry, Frederick Thomas Trouton and Alexander Trotter to assume they would be analogous to optical signaling and the Serbian American engineer Nikola Tesla to consider them useless for communication since "light" could not transmit further than line of sight. In 1892 the physicist William Crookes wrote on the possibilities of wireless telegraphy based on Hertzian waves and in 1893 Tesla proposed a system for transmitting intelligence and wireless power using the earth as the medium. Others, such as Amos Dolbear, Sir Oliver Lodge, Reginald Fessenden, Alexander Popov were involved in the development of components and theory involved with the transmission and reception of airborne electromagnetic waves for their own theoretical work or as a potential means of communication.

Over several years starting in 1894 the Italian inventor Guglielmo Marconi built the first engineering complete, commercially successful wireless telegraphy system based on airborne Hertzian waves. Marconi demonstrated the application of radio in military and marine communications and started a company for the development and propagation of radio communication services and equipment; the meaning and usage of the word "radio" has developed in parallel with developments within the field of communications and can be seen to have three distinct phases: electromagnetic waves and experimentation. In an 1864 presentation, published in 1865, James Clerk Maxwell proposed theories of electromagnetism, with mathematical proofs, that showed that light and predicted that radio and x-rays were all types of electromagnetic waves propagating through free space. In 1886–88 Heinrich Rudolf Hertz conducted a series of experiments that proved the existence of Maxwell's electromagnetic waves, using a frequency in what would be called the radio spectrum.

Many individuals—inventors, engineers and businessmen—constructed systems based on their own understanding of these and other phenomena, some predating Maxwell and Hertz's discoveries. Thus "wireless telegraphy" and radio wave-based systems can be attributed to multiple "inventors". Development from a laboratory demonstration to a commercial entity spanned several decades and required the efforts of many practitioners. In 1878, David E. Hughes noticed that sparks could be heard in a telephone receiver when experimenting with his carbon microphone, he developed this carbon-based detector further and could detect signals over a few hundred yards. He demonstrated his discovery to the Royal Society in 1880, but was told it was induction, therefore abandoned further research. Thomas Edison came across the electromagnetic phenomenon while experimenting with a telegraph at Menlo Park, he noted an unexplained transmission effect while experimenting with a telegraph. He referred to this as etheric force in an announcement on November 28, 1875.

Elihu Thomson published his findings on Edison's new "force", again attributing it to induction, an explanation that Edison accepted. Edison would go on the next year to take out U. S. Patent 465,971 on a system of electrical wireless communication between ships based on electrostatic coupling using the water and elevated terminals. Although this was not a radio system, Edison would sell his patent rights to his friend Guglielmo Marconi at the Marconi Company in 1903, rather than another interested party who might end up working against Marconi's interests. Between 1886 and 1888 Heinrich Rudolf Hertz published the results of his experiments wherein he was able to transmit electromagnetic waves through the air, proving Maxwell's electromagnetic theory. Thus, given Hertz comprehensive discoveries, radio waves were referred to as "Hertzian waves". Between 1890 and 1892 physicists such as John Perry, Frederick Thomas Trouton and William Crookes proposed electromagnetic or Hertzian waves as a navigation aid or means of communication, with Crookes writing on the possibilities of wireless telegraphy based on Hertzian waves in 1892.

After learning of Hertz' demonstrations of wireless transmission, inventor Nikola Tesla began developing his own systems based on Hertz' and Maxwell's ideas working tow

Poly (ADP-ribose) polymerase

Poly polymerase is a family of proteins involved in a number of cellular processes such as DNA repair, genomic stability, programmed cell death. The PARP family comprises 17 members, they have all different structures and functions in the cell. PARP1, PARP2, VPARP, Tankyrase-1 and -2 have a confirmed PARP activity. Others include PARP3, PARP6, TIPARP, PARP8, PARP9, PARP10, PARP11, PARP12, PARP14, PARP15, PARP16. PARP is composed of four domains of interest: a DNA-binding domain, a caspase-cleaved domain, an auto-modification domain, a catalytic domain; the DNA-binding domain is composed of two zinc finger motifs. In the presence of damaged DNA, the DNA-binding domain will bind the DNA and induce a conformational shift, it has been shown. This is integral in a programmed cell death model based on caspase cleavage inhibition of PARP; the auto-modification domain is responsible for releasing the protein from the DNA after catalysis. It plays an integral role in cleavage-induced inactivation; the main role of PARP is to detect and initiate an immediate cellular response to metabolic, chemical, or radiation-induced single-strand DNA breaks by signaling the enzymatic machinery involved in the SSB repair.

Once PARP detects a SSB, it binds to the DNA, undergoes a structural change, begins the synthesis of a polymeric adenosine diphosphate ribose chain, which acts as a signal for the other DNA-repairing enzymes. Target enzymes include DNA ligase III, DNA polymerase beta, scaffolding proteins such as X-ray cross-complementing gene 1. After repairing, the PAR chains are degraded via Poly glycohydrolase. NAD+ is required as substrate for generating ADP-ribose monomers, it has been thought that overactivation of PARP may deplete the stores of cellular NAD+ and induce a progressive ATP depletion and necrotic cell death, since glucose oxidation is inhibited. But more it was suggested that inhibition of hexokinase activity leads to defects in glycolysis. Basal PARP activity regulates basal bioenergetics. Note below that PARP is inactivated by caspase-3 cleavage during programmed cell death. PARP enzymes are essential in a number of cellular functions, including expression of inflammatory genes: PARP1 is required for the induction of ICAM-1 gene expression by cardiac myocytes and smooth muscle cells, in response to TNF.

The catalytic domain is responsible for Poly polymerization. This domain has a conserved motif, common to all members of the PARP family. PAR polymer can reach lengths of up to 200 nucleotides before inducing apoptotic processes; the formation of PAR polymer is similar to the formation of DNA polymer from nucleoside triphosphates. Normal DNA synthesis requires that a pyrophosphate act as the leaving group, leaving a single phosphate group linking deoxyribose sugars. PAR is synthesized using nicotinamide as the leaving group; this leaves a pyrophosphate as the linking group between ribose sugars rather than single phosphate groups. This creates some special bulk to a PAR bridge. One important function of PARP is assisting in the repair of single-strand DNA nicks, it binds sites with single-strand breaks through its N-terminal zinc fingers and will recruit XRCC1, DNA ligase III, DNA polymerase beta, a kinase to the nick. This is called base excision repair. PARP-2 has been shown to oligomerize with PARP-1 and, therefore, is implicated in BER.

The oligomerization has been shown to stimulate PARP catalytic activity. PARP-1 is known for its role in transcription through remodeling of chromatin by PARylating histones and relaxing chromatin structure, thus allowing transcription complex to access genes. PARP-1 and PARP-2 are activated by DNA single-strand breaks, both PARP-1 and PARP-2 knockout mice have severe deficiencies in DNA repair, increased sensitivity to alkylating agents or ionizing radiation. PARP activity measured in the permeabilized mononuclear leukocyte blood cells of thirteen mammalian species correlates with maximum lifespan of the species; the difference in activity between the longest-lived and shortest-lived species tested was 5-fold. Although the enzyme kinetics of the two enzymes were not different, human PARP-1 was found to have a two-fold higher specific automodification capacity than the rat enzyme, which the authors posited could account, in part, for the higher PARP activity in humans than rats. Lymphoblastoid cell lines established from blood samples of humans who were centenarians have higher PARP activity than cell lines from younger individuals, again indicating a linkage between longevity and repair capability.

These findings suggest. Thus, these findings support the DNA damage theory of aging, which assumes that un-repaired DNA damage is the underlying cause of aging, that DNA repair capability contributes to longevity; the tankyrases are PARPs that comprise ankyrin repeats, an oligomerization domain, a PARP catalytic domain. Tankyrases are known as PARP-5a and PARP-5b, they were named for their interaction with the telomere-associated TRF1 proteins and ankyrin repeats. They may allow the removal of telomer

Rob Stone (rapper)

Jaylen Robinson, better known as Rob Stone, is an American rapper from San Diego, California. He is best known for his debut single "Chill Bill" from his mixtape Straight Bummin. Jaylen Robinson was born on January 1995 in San Diego, California. From a young age, Jaylen was influenced by his father’s vintage music collection, expanded his listening to reggae, hip hop, rock, R&B, he attended college in Atlanta, where he first started teaching himself how to rap. Stone first released his first song "Chill Bill" on June 2014 on his SoundCloud, he wrote the song in the back of a police car. Stone went on to release his debut mixtape Straight Bummin' on February 8, 2015; the music video for "Chill Bill" was released on June 25, 2015 on his friend's YouTube channel called "Twelve O'Seven". Stone released the song as his debut single on June 17, 2016; the song debuted at number 99 on the Billboard Hot 100, has so far reached number 29 on the chart. The official remix of the song features Denzel Curry and Cousin Stizz.

In September 2016, Stone released his second mixtape. Don't Wait For It Rob Stone's SoundCloud Rob Stone's Twitter Rob Stone's Instagram Rob Stone's YouTube

2018 Iranian university protests

The 2018 Iranian university protests are a series of ongoing protests by Iranian university students in support of labour, teacher strikes, as well as protesting against the current situation of the country. The protests started on 4 December 2018, ahead of university day on 7 December, marked by protests. On 4 December 2018, students at the Amirkabir University of Technology in Tehran, gathered in support of the ongoing labour and teacher strikes. Students clashed with Basiji counter protesters. Students chanted "Cannons and weapons have no affect anymore", "Workers and students unite", "Jailed teachers and students must be freed", "Death to this deceptive government". Elsewhere in Tehran, students Allameh Tabataba'i University protested against the presence of members of the Ministry of Intelligence on the campus. On the same day students at the Babol Noshirvani University of Technology protested and chanted "The university is alive", "Stop crackdown on university students", "University students will die, but will not accept oppression".

Students at the Sahand University of Technology protested and held a hunger strike. Students at the Razi University of Kermanshah held a protest in support of workers in Khuzestan, chanted "Bread, workers council". On 29 December, students at the Islamic Azad University and Research Branch, Tehran gathered on campus to mourn and protest after ten people were killed in a bus accident on the campus on 25 December. Students demanded the resignation of the chairman of the Islamic Azad University Ali Akbar Velayati; the protesters, who numbered in the hundreds chanted against the incompetent officials whom they felt were responsible for the incident. Students at the Islamic Azad University and Research Branch, Tehran gathered for a second consecutive day of protests on 30 December; the students chanted "Velayati you are responsible for these killings" and "incompetent officials must be prosecuted". Video from the protests showed a car injuring two students. On 31 December 2018, students and other citizens gathered in front of the University of Tehran in solidarity with the students at the Islamic Azad University and Research Branch, Tehran.

Protestors were met by the security forces and anti-riot police who attempted to control the demonstration. Demonstrators clashed with the security forces and chanted "Death to the dictator", "Our fronts to the nation, our backs to the enemy", "Don't be scared, we are all together", "incompetent officials must resign". Earlier on Christmas day a bus taking about 30 students on a mountain road hit a concrete road which resulted to the death of 10 passenger and injury of 25 others. Students were from Islamic Azad University in north east of Iran. Iran’s officials are blamed for not using safety precautions, This bus was considered out of service six years ago

Charles Cherry

Charles Cameron Cherry was a British born actor. He was born to James Frederick Cherry and his wife, Lady Emily Louisa Haworth-Leslie at Greenwich, England, his mother was a relation to Norman Leslie, 19th Earl of Rothes. He spent a large part of his career in the United States as leading man to many beautiful star actresses i.e. Elsie de Wolfe, Maxine Elliott, Ethel Barrymore, Marie Doro and Elsie Ferguson, he appeared in The Mummy and the Hummingbird and Passers By. His sisters were a Titanic survivor, his spouse was Grace Dudley. Charles Cherry at the Internet Broadway Database Charles Cherry on IMDb Charles Cherry: North American Theatre Online portraits of Charles Cherry

Lucy Cox (artist)

Lucy Cox born in Chard, Somerset, UK, is a British abstract artist and curator. Cox received a Foundation Degree in Art & Design from Kingston University London, a Bachelor of Arts with Honours in Fine Art from Wimbledon College of Arts, University of the Arts London, and a Master of Arts in Culture and Management from City, University of London. Cox has exhibited her paintings in the UK and internationally, including an exhibition of British painters in China, has curated exhibitions in London. Andy Parkinson wrote of her work, "Lucy Cox's playful geometric arrangements inhabiting a believable three dimensional space, seem to celebrate the ways in which colour creates spatial ambiguities and irregularities". Cox's abstract paintings are described as juxtaposing the autonomy of geometry with repetition and spontaneity, she is a member of Contemporary British Painting and on the advisory board of The Priseman Seabrook Collections. 2020 - Dear Christine, Arthouse 1, London 2019 - Dear Christine, Elysium Gallery, Swansea, UK 2019 - Made in Britain.

Art Bermondsey Project Space, London 2017 - Contemporary Masters from Britain, Yantai Art Museum, China 2017 - Colour A Kind Of Bliss, The Crypt, London 2016 - Summer Exhibition, The Quay Arts, Isle of White, UK 2015/16 - Piercing The Veil, Simmons Contemporary, Simmons & Simmons, London 2015 - Geometry: Wonky and Otherwise, Déda, Derby, UK 2017 - Colour A Kind Of Bliss, The Crypt, London 2016 - Multiple Choices, Simmons Contemporary, Simmons & Simmons, London The Priseman Seabrook Collection, UKJiangsu Provincial Art Museum, China 2019 - Dear Christine.