A paramedic is a specialist healthcare professional who responds to emergency calls for medical help outside of a hospital. Paramedics work as part of the emergency medical services, most in ambulances; the scope of practice of a paramedic varies among countries, but includes autonomous decision making around the emergency care of patients. Not all ambulance personnel are paramedics, although the term is sometimes used informally to refer to any ambulance personnel. In English-speaking countries, there is an official distinction between paramedics and emergency medical technicians, in which paramedics have additional qualifications and are accountable to a professional regulatory body; the paramedic role is related to other healthcare positions the emergency medical technician role, with paramedics being a higher grade role, with more responsibility and autonomy. The role of a paramedic varies across the world, as EMS providers operate with many different models of care. In the Anglo-American model, paramedics are autonomous decision-makers.
In some countries such as the United Kingdom and South Africa, the paramedic role has developed into an autonomous health profession. In the Franco-German model, ambulance care is led by physicians. In some versions of this model, such as France, there is no direct equivalent to a paramedic. Ambulance staff have either the more advanced qualifications of a physician or less advanced training in first aid. In other versions of the Franco-German model, such as Germany, paramedics do exist, their role is to support a physician in the field, in a role more akin to a hospital nurse, rather than operating with clinical autonomy. The development of the profession has been a gradual move from transporting patients to hospital, to more advanced treatments in the field. In some countries, the paramedic may take on the role as part of a system to prevent hospitalisation and, through practitioners, are able to prescribe certain medications, or undertaking'see and refer' visits, where the paramedic directly refers a patient to specialist services without taking them to hospital.
Throughout the evolution of pre-hospitalisation care, there has been an ongoing association with military conflict. One of the first indications of a formal process for managing injured people dates from the Imperial Legions of Rome, where aging Centurions, no longer able to fight, were given the task of organizing the removal of the wounded from the battlefield and providing some form of care; such individuals, although not physicians, were among the world's earliest surgeons by default, being required to suture wounds and complete amputations. A similar situation existed in the Crusades, with the Knights Hospitaller of the Order of St. John of Jerusalem filling a similar function. While civilian communities had organized ways to deal with prehospitalisation care and transportation of the sick and dying as far back as the bubonic plague in London between 1598 and 1665, such arrangements were ad hoc and temporary. In time, these arrangements began to formalize and become permanent. During the American Civil War, Jonathan Letterman devised a system of mobile field hospitals employing the first uses of the principles of triage.
After returning home, some veterans began to attempt to apply what had they had seen on the battlefield to their own communities, commenced the creation of volunteer life-saving squads and ambulance corps. These early developments in formalized ambulance services were decided at local levels, this led to services being provided by diverse operators such as the local hospital, fire brigade, or funeral directors who possessed the only local transport allowing a passenger to lie down. In most cases these ambulances were operated by drivers and attendants with little or no medical training, it was some time before formal training began to appear in some units. An early example was the members of the Toronto Police Ambulance Service receiving a mandatory five days of training from St. John as early as 1889. Prior to World War I motorized ambulances started to be developed, but once they proved their effectiveness on the battlefield during the war the concept spread to civilian systems. In terms of advanced skills, once again the military led the way.
During World War II and the Korean War battlefield medics administered painkilling narcotics by injection in emergency situations, pharmacists' mates on warships were permitted to do more without the guidance of a physician. The Korean War marked the first widespread use of helicopters to evacuate the wounded from forward positions to medical units, leading to the rise of the term "medivac"; these innovations would not find their way into the civilian sphere for nearly twenty more years. By the early 1960s experiments in improving medical care had begun in some civilian centres. One early experiment involved the provision of pre-hospital cardiac care by physicians in Belfast, Northern Ireland, in 1966; this was repeated in Toronto, Canada in 1968 using a single ambulance called Cardiac One, staffed by a regular ambulance crew, along with a hospital intern to perform the advanced procedures. While both of these experiments had certain levels of success, the technology had not yet reached a sufficiently advanced level to be effective.
In 1966, a report called Accid
Bravo (UK TV channel)
Bravo was a British television channel owned by Living TV Group, a subsidiary of BSkyB. Its target audience was males in their 20s to early 40s, it broadcast a variety of original productions. The Bravo channel ceased broadcasting on 1 January 2011, its most popular programmes including: Spartacus: Blood and Sand, Leverage, Dog the Bounty Hunter, Star Trek, TNA Wrestling, Sea and A&E, Motorway Patrol, Highway Patrol, Brit Cops and Caribbean Cops moved to other Sky channels. Bravo was launched on 31 December 1985 as a cable only channel, created by United Artists Programming broadcasting black & white B-movies from the 1950s and 1960s and TV series; the channel was a cassette-delivered service provided to cable headends for automatic play-out. In 1991, United Artists merged with their largest shareholder TCI, to form the largest cable operator in the United States. TCI and US West announced a joint venture and, in 1992, the joint venture company became Telewest Communications. In 1993, talks were held with Tele-Communications Inc. which resulted in Flextech acquiring TCI's European programming business in exchange for shares.
By January, the deal was complete with TCI, allowing it to acquire 60.4% of Flextech while Flextech acquired 100% of Bravo, 25% of UK Gold, 31% of UK Living, 25% of the Children's Channel which increased its share in that channel. On 22 July 1993, Bravo launched on the Astra 1C satellite in anticipation of the launch of Sky Multichannels in September 1993. With the launch on Astra, the channel started broadcasting between noon and midnight, until 3 February 1997, when Trouble launched and took over the channel's afternoon and early evening broadcast hours, meaning Bravo would broadcast between 8pm to 6am. During mornings, European Business News time shared with the channel on weekdays and Living on weekends until 2001, its programming output was altered around the same time, when the channel obtained many of the ITC Entertainment productions which included the cult series The Avengers. It upgraded its on-screen image with an elaborate station identifier of a modernist skyscraper under rolling thunderclouds and promoted itself as'Timewarp Television'.
It used both Roger Tony Curtis to feature in speciality shot trails. Armstrong and Miller first made their broadcast television appearance on Bravo in a series of presentation promotions during its Cult Weekend on 5 August 1995. In 1996, a policy change to withdraw the black & white shows contributed to the channel moving on to specialise in science fiction and horror with movies from the Troma Entertainment catalogue, it became known for showing crime documentaries by day and adult programming at night. It subsequently decreased increased sports and imported shows such as Alias. Moving into professional wrestling, Bravo aired Extreme Championship Wrestling's show ECW Hardcore TV from 1996–2000. With professional wrestling, Bravo aired World Championship Wrestling's flagship show Nitro during WCW's final year in business. On 28 August 2005, the channel started showing Serie A Italian football, bringing back the Channel 4 format Football Italia. However, poor viewing figures resulted first in the cancellation of the weekly Gazetta Football Italia show the announcement that Bravo would stop showing Italian Football altogether after 23 December 2006.
The channel's other highest-profile sports coverage was Ultimate Fighting Championship archives, for which it held exclusive UK rights, as well as recent events, as well as the related reality TV show The Ultimate Fighter. From January 2007, Bravo's sister channel Bravo 2 had the exclusive UK rights to broadcast Total Nonstop Action Wrestling programming, a two-day delay from the American broadcast of TNA's weekly show TNA iMPACT! and a three-day delay for TNA's monthly Pay Per Views. On 5 January 2008, TNA iMPACT was moved to Bravo with replays of the show on Bravo 2. Bravo's original contract for TNA Wrestling programming was for eighteen months and was distributed by RDA TV. From 3 June 2008 onward, along with the other Living TV Group owned channels began broadcasting in widescreen; this was coupled with a redesign of the on-screen graphic. On 25 May 2010, Virgin Media Television unveiled new channel branding for Bravo to coincide with a major new series Spartacus: Blood and Sand, it involved a new logo to "match the premium content and ambition of the channel" along with a new strapline, "Bravo: Home of the Brave".
On 15 September 2010, BSkyB announced that it would close Bravo as well as its sister channel Bravo 2. For November 2010, Bravo rebranded as Brav-Mo to celebrate Movember. From 24 to 31 December 2010, Bravo celebrated its final week with a marathon of its most popular shows called "Bravo, We Salute You". On 1 January 2011 at 4:00 am, Bravo ceased broadcasting on all platforms; the last program aired was World's Most Amazing Videos. In August 2013, it was revealed that BSkyB had registered the trademark for'Sky Bravo', paving the way for a possible relaunch of the channel, although nothing has been heard about it since. Bravo on TV Ark
Television, sometimes shortened to tele or telly, is a telecommunication medium used for transmitting moving images in monochrome, or in color, in two or three dimensions and sound. The term can refer to a television set, a television program, or the medium of television transmission. Television is a mass medium for advertising and news. Television became available in crude experimental forms in the late 1920s, but it would still be several years before the new technology would be marketed to consumers. After World War II, an improved form of black-and-white TV broadcasting became popular in the United States and Britain, television sets became commonplace in homes and institutions. During the 1950s, television was the primary medium for influencing public opinion. In the mid-1960s, color broadcasting was introduced in most other developed countries; the availability of multiple types of archival storage media such as Betamax, VHS tape, local disks, DVDs, flash drives, high-definition Blu-ray Discs, cloud digital video recorders has enabled viewers to watch pre-recorded material—such as movies—at home on their own time schedule.
For many reasons the convenience of remote retrieval, the storage of television and video programming now occurs on the cloud. At the end of the first decade of the 2000s, digital television transmissions increased in popularity. Another development was the move from standard-definition television to high-definition television, which provides a resolution, higher. HDTV may be transmitted in various formats: 1080p, 720p. Since 2010, with the invention of smart television, Internet television has increased the availability of television programs and movies via the Internet through streaming video services such as Netflix, Amazon Video, iPlayer and Hulu. In 2013, 79 % of the world's households owned; the replacement of early bulky, high-voltage cathode ray tube screen displays with compact, energy-efficient, flat-panel alternative technologies such as LCDs, OLED displays, plasma displays was a hardware revolution that began with computer monitors in the late 1990s. Most TV sets sold in the 2000s were flat-panel LEDs.
Major manufacturers announced the discontinuation of CRT, DLP, fluorescent-backlit LCDs by the mid-2010s. In the near future, LEDs are expected to be replaced by OLEDs. Major manufacturers have announced that they will produce smart TVs in the mid-2010s. Smart TVs with integrated Internet and Web 2.0 functions became the dominant form of television by the late 2010s. Television signals were distributed only as terrestrial television using high-powered radio-frequency transmitters to broadcast the signal to individual television receivers. Alternatively television signals are distributed by coaxial cable or optical fiber, satellite systems and, since the 2000s via the Internet; until the early 2000s, these were transmitted as analog signals, but a transition to digital television is expected to be completed worldwide by the late 2010s. A standard television set is composed of multiple internal electronic circuits, including a tuner for receiving and decoding broadcast signals. A visual display device which lacks a tuner is called a video monitor rather than a television.
The word television comes from Ancient Greek τῆλε, meaning'far', Latin visio, meaning'sight'. The first documented usage of the term dates back to 1900, when the Russian scientist Constantin Perskyi used it in a paper that he presented in French at the 1st International Congress of Electricity, which ran from 18 to 25 August 1900 during the International World Fair in Paris; the Anglicised version of the term is first attested in 1907, when it was still "...a theoretical system to transmit moving images over telegraph or telephone wires". It was "...formed in English or borrowed from French télévision." In the 19th century and early 20th century, other "...proposals for the name of a then-hypothetical technology for sending pictures over distance were telephote and televista." The abbreviation "TV" is from 1948. The use of the term to mean "a television set" dates from 1941; the use of the term to mean "television as a medium" dates from 1927. The slang term "telly" is more common in the UK; the slang term "the tube" or the "boob tube" derives from the bulky cathode ray tube used on most TVs until the advent of flat-screen TVs.
Another slang term for the TV is "idiot box". In the 1940s and throughout the 1950s, during the early rapid growth of television programming and television-set ownership in the United States, another slang term became used in that period and continues to be used today to distinguish productions created for broadcast on television from films developed for presentation in movie theaters; the "small screen", as both a compound adjective and noun, became specific references to television, while the "big screen" was used to identify productions made for theatrical release. Facsimile transmission systems for still photographs pioneered methods of mechanical scanning of images in the early 19th century. Alexander Bain introduced the facsimile machine between 1843 and 1846. Frederick Bakewell demonstrated a working laboratory version in 1851. Willoughby Smith discovered the photoconductivity of the element selenium in 1873; as a 23-year-old German university student, Paul Julius Gottlieb Nipkow proposed and patented the Nipkow disk in 1884.
This was a spinning disk with a spiral pattern of holes in it, so each hole scanned a line of the image. Although he never built a working model
Satellite television is a service that delivers television programming to viewers by relaying it from a communications satellite orbiting the Earth directly to the viewer's location. The signals are received via an outdoor parabolic antenna referred to as a satellite dish and a low-noise block downconverter. A satellite receiver decodes the desired television programme for viewing on a television set. Receivers can be a built-in television tuner. Satellite television provides a wide range of services, it is the only television available in many remote geographic areas without terrestrial television or cable television service. Modern systems signals are relayed from a communications satellite on the Ku band frequencies requiring only a small dish less than a meter in diameter; the first satellite TV systems were an obsolete type now known as television receive-only. These systems received weaker analog signals transmitted in the C-band from FSS type satellites, requiring the use of large 2–3-meter dishes.
These systems were nicknamed "big dish" systems, were more expensive and less popular. Early systems used analog signals, but modern ones use digital signals which allow transmission of the modern television standard high-definition television, due to the improved spectral efficiency of digital broadcasting; as of 2018, Star One C2 from Brazil is the only remaining satellite broadcasting in analog signals, as well as one channel on AMC-11 from the United States. Different receivers are required for the two types; some transmissions and channels are unencrypted and therefore free-to-air or free-to-view, while many other channels are transmitted with encryption, requiring the viewer to subscribe and pay a monthly fee to receive the programming. The satellites used for broadcasting television are in a geostationary orbit 37,000 km above the earth's equator; the advantage of this orbit is that the satellite's orbital period equals the rotation rate of the Earth, so the satellite appears at a fixed position in the sky.
Thus the satellite dish antenna which receives the signal can be aimed permanently at the location of the satellite, does not have to track a moving satellite. A few systems instead use a elliptical orbit with inclination of +/−63.4 degrees and orbital period of about twelve hours, known as a Molniya orbit. Satellite television, like other communications relayed by satellite, starts with a transmitting antenna located at an uplink facility. Uplink satellite dishes are large, as much as 9 to 12 meters in diameter; the increased diameter results in more accurate aiming and increased signal strength at the satellite. The uplink dish is pointed toward a specific satellite and the uplinked signals are transmitted within a specific frequency range, so as to be received by one of the transponders tuned to that frequency range aboard that satellite; the transponder re-transmits the signals back to Earth at a different frequency in the 10.7-12.7 GHz band, but some still transmit in the C-band, Ku-band, or both.
The leg of the signal path from the satellite to the receiving Earth station is called the downlink. A typical satellite has up to 32 Ku-band or 24 C-band transponders, or more for Ku/C hybrid satellites. Typical transponders each have a bandwidth between 50 MHz; each geostationary C-band satellite needs to be spaced 2° longitude from the next satellite to avoid interference. This means that there is an upper limit of 360/2 = 180 geostationary C-band satellites or 360/1 = 360 geostationary Ku-band satellites. C-band transmission is susceptible to terrestrial interference while Ku-band transmission is affected by rain; the latter is more adversely affected by ice crystals in thunder clouds. On occasion, sun outage will occur when the sun lines up directly behind the geostationary satellite to which the receiving antenna is pointed; the downlink satellite signal, quite weak after traveling the great distance, is collected with a parabolic receiving dish, which reflects the weak signal to the dish's focal point.
Mounted on brackets at the dish's focal point is a device called a feedhorn or collector. The feedhorn is a section of waveguide with a flared front-end that gathers the signals at or near the focal point and conducts them to a probe or pickup connected to a low-noise block downconverter; the LNB amplifies the signals and downconverts them to a lower block of intermediate frequencies in the L-band. The original C-band satellite television systems used a low-noise amplifier connected to the feedhorn at the focal point of the dish; the amplified signal, still at the higher microwave frequencies, had to be fed via expensive low-loss 50-ohm impedance gas filled hardline coaxial cable with complex N-connectors to an indoor receiver or, in other designs, a downconverter for downconversion to an intermediate frequency. The channel selection was controlled by a voltage tuned oscillator with the tuning voltage being fed via a separate cable to the headend, but this design evolved. Designs for microstrip-based converters for amateur radio frequencies were adapted for the 4 GHz C-band.
Central to these designs was concept of block downconversion of a range of frequencies to a lower, more handled IF. The advantages of using an LNB are that cheaper cable can be used to connect the indoor receiver to the satellite te