The Kardashian Index ( K-Index ), named after media personality Kim Kardashian , is a satirical measure of the discrepancy between a scientist's social media profile and publication record. Proposed by Neil Hall in 2014, the measure compares the number of followers a research scientist has on Twitter to the number of citations they have for their peer-reviewed work.
122-512: The relationship between the expected number of Twitter followers F {\displaystyle F} given the number of citations C {\displaystyle C} is described as F ( C ) = 43.3 C 0.32 , {\displaystyle F(C)=43.3\,C^{0.32},} which is derived from the Twitter accounts and citation counts of a "randomish selection of 40 scientists" in 2014. The Kardashian Index
244-499: A Ruhmkorff coil with a high speed alternator he had been developing as part of an improved arc lighting system but found that the high-frequency current overheated the iron core and melted the insulation between the primary and secondary windings in the coil. To fix this problem Tesla came up with his "oscillating transformer", with an air gap instead of insulating material between the primary and secondary windings and an iron core that could be moved to different positions in or out of
366-613: A cold cathode electrical discharge tube. Tesla may have inadvertently captured an X-ray image—predating, by a few weeks, Wilhelm Röntgen 's December 1895 announcement of the discovery of X-rays—when he tried to photograph Mark Twain illuminated by a Geissler tube , an earlier type of gas discharge tube. The only thing captured in the image was the metal locking screw on the camera lens. In March 1896, after hearing of Röntgen's discovery of X-ray and X-ray imaging ( radiography ), Tesla proceeded to do his own experiments in X-ray imaging, developing
488-403: A commutator , thus avoiding sparking and the high maintenance of constantly servicing and replacing mechanical brushes. Along with getting the motor patented, Peck and Brown arranged to get the motor publicized, starting with independent testing to verify it was a functional improvement, followed by press releases sent to technical publications for articles to run concurrently with the issue of
610-625: A healthy diet are also recommended. Supportive care in severe cases includes treatment to relieve symptoms , fluid therapy , oxygen support and prone positioning , and medications or devices to support other affected vital organs. More severe cases may need treatment in hospital. In those with low oxygen levels, use of the glucocorticoid dexamethasone is recommended to reduce mortality. Noninvasive ventilation and, ultimately, admission to an intensive care unit for mechanical ventilation may be required to support breathing. Extracorporeal membrane oxygenation (ECMO) has been used to address
732-760: A thermo-magnetic motor idea, they agreed to back the inventor financially and handle his patents. Together they formed the Tesla Electric Company in April 1887, with an agreement that profits from generated patents would go 1 ⁄ 3 to Tesla, 1 ⁄ 3 to Peck and Brown, and 1 ⁄ 3 to fund development. They set up a laboratory for Tesla at 89 Liberty Street in Manhattan, where he worked on improving and developing new types of electric motors, generators, and other devices. In 1887, Tesla developed an induction motor that ran on alternating current (AC),
854-615: A variant of concern (VoC) or a variant of interest (VoI). Many of these variants have shared the more infectious D614G . As of May 2023, the WHO had downgraded all variants of concern to previously circulating as these were no longer detected in new infections. Sub-lineages of the Omicron variant (BA.1 – BA.5) were considered separate VoCs by the WHO until they were downgraded in March 2023 as no longer widely circulating. As of 24 September 2024 ,
976-615: A bonus he did not receive, either for redesigning generators or for the arc lighting system that was shelved. Tesla had previous run-ins with the Edison company over unpaid bonuses he believed he had earned. In his autobiography, Tesla stated the manager of the Edison Machine Works offered a $ 50,000 bonus to design "twenty-four different types of standard machines" "but it turned out to be a practical joke". Later versions of this story have Thomas Edison himself offering and then reneging on
1098-646: A collection of early notes and research material, models, and demonstration pieces, including many that had been exhibited at the 1893 Worlds Colombian Exposition. Tesla told The New York Times "I am in too much grief to talk. What can I say?". After the fire Tesla moved to 46 & 48 East Houston Street and rebuilt his lab on the 6th and 7th floors. Starting in 1894, Tesla began investigating what he referred to as radiant energy of "invisible" kinds after he had noticed damaged film in his laboratory in previous experiments (later identified as "Roentgen rays" or " X-rays "). His early experiments were with Crookes tubes ,
1220-493: A comprehensive international study. Such deaths include deaths due to healthcare capacity constraints and priorities, as well as reluctance to seek care (to avoid possible infection). Further research may help distinguish the proportions directly caused by COVID-19 from those caused by indirect consequences of the pandemic. In May 2022, the WHO estimated the number of excess deaths by the end of 2021 to be 14.9 million compared to 5.4 million reported COVID-19 deaths, with
1342-566: A contract to Westinghouse Electric for building a two-phase AC generating system at the Niagara Falls, based on Tesla's advice and Westinghouse's demonstration at the Columbian Exposition. At the same time, a further contract was awarded to General Electric to build the AC distribution system. In 1895, Edward Dean Adams, impressed with what he saw when he toured Tesla's lab, agreed to help found
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#17328586395571464-408: A demonstration he had previously performed throughout America and Europe; these included using high-voltage, high-frequency alternating current to light wireless gas-discharge lamps . An observer noted: Within the room were suspended two hard-rubber plates covered with tin foil. These were about fifteen feet apart and served as terminals of the wires leading from the transformers. When the current
1586-514: A ditch digger for $ 2 per day. Later in life Tesla recounted that part of 1886 as a time of hardship, writing "My high education in various branches of science, mechanics and literature seemed to me like a mockery". In late 1886, Tesla met Alfred S. Brown, a Western Union superintendent, and New York attorney Charles Fletcher Peck. The two men were experienced in setting up companies and promoting inventions and patents for financial gain. Based on Tesla's new ideas for electrical equipment, including
1708-506: A frustrating period because of conflicts with the other Westinghouse engineers over how best to implement AC power. Between them, they settled on a 60-cycle AC system that Tesla proposed (to match the working frequency of Tesla's motor), but they soon found that it would not work for streetcars, since Tesla's induction motor could run only at a constant speed. They ended up using a DC traction motor instead. Tesla's demonstration of his induction motor and Westinghouse's subsequent licensing of
1830-555: A high-energy single-terminal vacuum tube of his own design that had no target electrode and that worked from the output of the Tesla coil (the modern term for the phenomenon produced by this device is bremsstrahlung or braking radiation ). In his research, Tesla devised several experimental setups to produce X-rays. Tesla held that, with his circuits, the "instrument will ... enable one to generate Roentgen rays of much greater power than obtainable with ordinary apparatus". Tesla noted
1952-590: A large number of people". During the COVID-19 pandemic, as with other pandemics, the meaning of this term has been challenged. The end of a pandemic or other epidemic only rarely involves the total disappearance of a disease, and historically, much less attention has been given to defining the ends of epidemics than their beginnings. The ends of particular epidemics have been defined in a variety of ways, differing according to academic field, and differently based on location and social group. An epidemic's end can be considered
2074-448: A median range of 0.24% to 1.49%. IFRs rise as a function of age (from 0.002% at age 10 and 0.01% at age 25, to 0.4% at age 55, 1.4% at age 65, 4.6% at age 75, and 15% at age 85). These rates vary by a factor of ≈10,000 across the age groups. For comparison, the IFR for middle-aged adults is two orders of magnitude higher than the annualised risk of a fatal automobile accident and much higher than
2196-571: A power system format that was rapidly expanding in Europe and the United States because of its advantages in long-distance, high-voltage transmission. The motor used polyphase current, which generated a rotating magnetic field to turn the motor (a principle that Tesla claimed to have conceived in 1882). This innovative electric motor, patented in May 1888, was a simple self-starting design that did not need
2318-493: A quip about their "Parisian" being out all night. After Tesla told them he had been up all night fixing the Oregon , Edison commented to Batchelor that "this is a damned good man". One of the projects given to Tesla was to develop an arc lamp -based street lighting system. Arc lighting was the most popular type of street lighting but it required high voltages and was incompatible with the Edison low-voltage incandescent system, causing
2440-815: A random sample have consistently found that total infections considerably exceed the reported case counts. Many countries, early on, had official policies to not test those with only mild symptoms. The strongest risk factors for severe illness are obesity, complications of diabetes , anxiety disorders, and the total number of conditions. During the start of the COVID-19 pandemic it was not clear whether young people were less likely to be infected, or less likely to develop symptoms and be tested. A retrospective cohort study in China found that children and adults were just as likely to be infected. Among more thorough studies, preliminary results from 9 April 2020 found that in Gangelt ,
2562-669: A range of experiments with mechanical oscillators /generators, electrical discharge tubes, and early X-ray imaging . He also built a wirelessly controlled boat, one of the first ever exhibited. Tesla became well known as an inventor and demonstrated his achievements to celebrities and wealthy patrons at his lab, and was noted for his showmanship at public lectures. Throughout the 1890s, Tesla pursued his ideas for wireless lighting and worldwide wireless electric power distribution in his high-voltage, high-frequency power experiments in New York and Colorado Springs . In 1893, he made pronouncements on
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#17328586395572684-537: A required subject; and he was illiterate in Czech , another required subject. Tesla did, however, attend lectures in philosophy at the university as an auditor but he did not receive grades for the courses. Tesla moved to Budapest , Hungary , in 1881 to work under Tivadar Puskás at a telegraph company, the Budapest Telephone Exchange. Upon arrival, Tesla realized that the company, then under construction,
2806-526: A royalty of $ 2.50 per AC horsepower produced by each motor. Westinghouse also hired Tesla for one year for the large fee of $ 2,000 ($ 67,800 in today's dollars ) per month to be a consultant at the Westinghouse Electric & Manufacturing Company's Pittsburgh labs. During that year, Tesla worked in Pittsburgh, helping to create an alternating current system to power the city's streetcars. He found it
2928-632: A series of New York hotels, leaving behind unpaid bills. He died in New York City in January 1943. Tesla's work fell into relative obscurity following his death, until 1960, when the General Conference on Weights and Measures named the International System of Units (SI) measurement of magnetic flux density the tesla in his honor. There has been a resurgence in popular interest in Tesla since
3050-487: A series of proposals and open competitions on how best to do it. Among the systems proposed by several US and European companies were two-phase and three-phase AC, high-voltage DC, and compressed air. Adams asked Tesla for information about the current state of all the competing systems. Tesla advised Adams that a two-phased system would be the most reliable and that there was a Westinghouse system to light incandescent bulbs using two-phase alternating current. The company awarded
3172-457: A social phenomenon, not just a biological one. Time reported in March 2024 that expert opinions differ on whether or not COVID-19 is considered endemic or pandemic, and that the WHO continued to call the disease a pandemic on its website. During the initial outbreak in Wuhan , the virus and disease were commonly referred to as "coronavirus", "Wuhan coronavirus", "the coronavirus outbreak" and
3294-451: A test. Conversely, deaths of people who died from underlying conditions following a positive test may be included. Countries such as Belgium include deaths from suspected cases, including those without a test, thereby increasing counts. Official death counts have been claimed to underreport the actual death toll, because excess mortality (the number of deaths in a period compared to a long-term average) data show an increase in deaths that
3416-511: A way to provide electricity to all potential customers and started branding their polyphase AC system as the "Tesla Polyphase System". They believed that Tesla's patents gave them patent priority over other polyphase AC systems. Westinghouse Electric asked Tesla to participate in the 1893 World's Columbian Exposition in Chicago where the company had a large space in the "Electricity Building" devoted to electrical exhibits. Westinghouse Electric won
3538-410: A way to transmit worldwide communications. At the time Tesla was formulating his ideas, there was no feasible way to wirelessly transmit communication signals over long distances, let alone large amounts of power. Tesla had studied radio waves early on, and came to the conclusion that part of the existing study on them, by Hertz, was incorrect. Also, this new form of radiation was widely considered at
3660-454: A wireless lighting system based on near-field inductive and capacitive coupling and conducted a series of public demonstrations where he lit Geissler tubes and even incandescent light bulbs from across a stage. He spent most of the decade working on variations of this new form of lighting with the help of various investors but none of the ventures succeeded in making a commercial product out of his findings. In 1893 at St. Louis , Missouri,
3782-518: Is associated with COVID-19 and is reported in as many as 88% of cases. The disease is mainly transmitted via the respiratory route when people inhale droplets and small airborne particles (that form an aerosol ) that infected people exhale as they breathe, talk, cough, sneeze, or sing. Infected people are more likely to transmit COVID-19 when they are physically close to other non-infected individuals. However, infection can occur over longer distances, particularly indoors. SARS‑CoV‑2 belongs to
Kardashian Index - Misplaced Pages Continue
3904-600: Is discouraged altogether by the World Health Organization (WHO), due to limited evidence of its efficacy. The severity of COVID-19 varies. It may take a mild course with few or no symptoms, resembling other common upper respiratory diseases such as the common cold . In 3–4% of cases (7.4% for those over age 65) symptoms are severe enough to cause hospitalisation. Mild cases typically recover within two weeks, while those with severe or critical diseases may take three to six weeks to recover. Among those who have died,
4026-439: Is intended to provide acquired immunity against severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2), the virus that causes coronavirus disease 2019 ( COVID-19 ). Prior to the COVID-19 pandemic, an established body of knowledge existed about the structure and function of coronaviruses causing diseases like severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). This knowledge accelerated
4148-485: Is not explained by COVID-19 deaths alone. Using such data, estimates of the true number of deaths from COVID-19 worldwide have included a range from 18.2 to 33.5 million (≈27.4 million) by 18 November 2023 by The Economist , as well as over 18.5 million by 1 April 2023 by the Institute for Health Metrics and Evaluation and ≈18.2 million (earlier) deaths between 1 January 2020, and 31 December 2021, by
4270-711: Is the number that researcher should have, given their citations. A high K-index indicates an over-blown scientific fame, while a low K-index suggests that a scientist is being undervalued. According to the author Hall, researchers whose K-index > 5 can be considered "Science Kardashians". Hall wrote: I propose that all scientists calculate their own K-index on an annual basis and include it in their Twitter profile. Not only does this help others decide how much weight they should give to someone’s 140 character wisdom, it can also be an incentive – if your K-index gets above 5, then it’s time to get off Twitter and write those papers. Hall also added "a serious note" noticing
4392-452: Is the ratio of deaths to diagnoses. This metric can be misleading because of the delay between symptom onset and death and because testing focuses on symptomatic individuals. Based on Johns Hopkins University statistics, the global CFR was 1.02 percent (6,881,955 deaths for 676,609,955 cases) as of 10 March 2023. The number varies by region and has generally declined over time. Several variants have been named by WHO and labelled as
4514-406: Is the seventh known coronavirus to infect people, after 229E , NL63 , OC43 , HKU1 , MERS-CoV , and the original SARS-CoV . The standard method of testing for presence of SARS-CoV-2 is a nucleic acid test , which detects the presence of viral RNA fragments. As these tests detect RNA but not infectious virus, its "ability to determine duration of infectivity of patients is limited." The test
4636-408: Is thus calculated as K-index = F a F ( C ) , {\displaystyle {\text{K-index}}={\frac {F_{a}}{F(C)}},} where F a {\displaystyle F_{a}} is the actual number of Twitter followers of researcher X {\displaystyle X} , and F ( C ) {\displaystyle F(C)}
4758-614: Is typically done on respiratory samples obtained by a nasopharyngeal swab ; however, a nasal swab or sputum sample may also be used. The WHO has published several testing protocols for the disease. Preventive measures to reduce the chances of infection include getting vaccinated, staying at home or spending more time outdoors, avoiding crowded places, keeping distance from others, wearing a mask in public, ventilating indoor spaces, managing potential exposure durations, washing hands with soap and water often and for at least twenty seconds, practising good respiratory hygiene, and avoiding touching
4880-496: The New York Herald Tribune published an article on Tesla, in which he recalled an event that occasionally took place while experimenting with his single-electrode vacuum tubes. A minute particle would break off the cathode, pass out of the tube, and physically strike him: Tesla said he could feel a sharp stinging pain where it entered his body, and again at the place where it passed out. In comparing these particles with
5002-567: The Austrian Empire , Tesla first studied engineering and physics in the 1870s without receiving a degree. He then gained practical experience in the early 1880s working in telephony and at Continental Edison in the new electric power industry . In 1884 he immigrated to the United States, where he became a naturalized citizen . He worked for a short time at the Edison Machine Works in New York City before he struck out on his own. With
Kardashian Index - Misplaced Pages Continue
5124-532: The COVID-19 pandemic were shunned as a fringe minority by those in favor of the John Snow Memorandum . According to him, the latter used their large numbers of followers on Twitter and other social media and op-eds to shape a scientific " groupthink " against the former, who had less influence. The version of the index that Ioannidis used Scopus citations instead of Google Scholar citations, since many of
5246-713: The Franklin Institute in Philadelphia , Pennsylvania and the National Electric Light Association , Tesla told onlookers that he was sure a system like his could eventually conduct "intelligible signals or perhaps even power to any distance without the use of wires" by conducting it through the Earth. Tesla served as a vice-president of the American Institute of Electrical Engineers from 1892 to 1894,
5368-744: The Higher Real Gymnasium where the classes were held in German, as it was usual throughout schools within the Austro-Hungarian Military Frontier . Later in his patent applications, before he obtained American citizenship, Tesla would identify himself as 'of Smiljan, Lika , border country of Austria-Hungary '. Tesla later wrote that he became interested in demonstrations of electricity by his physics professor. Tesla noted that these demonstrations of this "mysterious phenomena" made him want "to know more of this wonderful force". Tesla
5490-501: The Huanan Seafood Wholesale Market there, but it is possible that human-to-human transmission began earlier. Molecular clock analysis suggests that the first cases were likely to have been between October and November 2019. The scientific consensus is that the virus is most likely of a zoonotic origin, from bats or another closely related mammal. While other explanations such as speculations that SARS-CoV-2
5612-582: The Imperial-Royal Technical College in Graz in 1875 on a Military Frontier scholarship. Tesla passed nine exams (nearly twice as many as required ) and received a letter of commendation from the dean of the technical faculty to his father, which stated, "Your son is a star of first rank." At Graz, Tesla noted his fascination with the detailed lectures on electricity presented by Professor Jakob Pöschl and described how he made suggestions on improving
5734-407: The Institute for Health Metrics and Evaluation estimating the true number of cases as of early 2022 to be in the billions. One measure that public health officials and policymakers have used to monitor the pandemic and guide decision-making is the test positivity rate ("percent positive"). According to Johns Hopkins in 2020, one benchmark for a "too high" per cent positive is 5%, which was used by
5856-665: The Tesla Electric Light and Manufacturing Company . Tesla worked for the rest of the year obtaining the patents that included an improved DC generator, the first patents issued to Tesla in the US, and building and installing the system in Rahway , New Jersey. Tesla's new system gained notice in the technical press, which commented on its advanced features. The investors showed little interest in Tesla's ideas for new types of alternating current motors and electrical transmission equipment. After
5978-547: The basic reproduction number (R 0 ) for COVID-19 in January 2020 were between 1.4 and 2.5, but a subsequent analysis claimed that it may be about 5.7 (with a 95 per cent confidence interval of 3.8 to 8.9). In December 2021, the number of cases continued to climb due to several factors, including new COVID-19 variants. As of that 28 December, 282,790,822 individuals worldwide had been confirmed as infected. As of 14 April 2022 , over 500 million cases were confirmed globally. Most cases are unconfirmed, with
6100-474: The coronavirus pandemic and COVID pandemic ), caused by severe acute respiratory syndrome coronavirus 2 ( SARS-CoV-2 ), began with an outbreak of COVID-19 in Wuhan , China, in December 2019. It spread to other areas of Asia, and then worldwide in early 2020. The World Health Organization (WHO) declared the outbreak a public health emergency of international concern (PHEIC) on 30 January 2020, and assessed
6222-439: The financial panic of 1890 , causing investors to call in their loans to Westinghouse Electric. The sudden cash shortage forced the company to refinance its debts. The new lenders demanded that Westinghouse cut back on what looked like excessive spending on acquisition of other companies, research, and patents, including the per motor royalty in the Tesla contract. At that point, the Tesla induction motor had been unsuccessful and
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#17328586395576344-474: The variants of interest as specified by the World Health Organization are BA.2.86 and JN.1, and the variants under monitoring are JN.1.7, KP.2, KP.3, KP.3.1.1, JN.1.18, LB.1, and XEC. Symptoms of COVID-19 are variable, ranging from mild symptoms to severe illness. Common symptoms include headache, loss of smell and taste , nasal congestion and runny nose , cough, muscle pain , sore throat , fever, diarrhoea , and breathing difficulties . People with
6466-429: The "Wuhan coronavirus outbreak", with the disease sometimes called "Wuhan pneumonia ". In January 2020, the WHO recommended 2019-nCoV and 2019-nCoV acute respiratory disease as interim names for the virus and disease per 2015 international guidelines against using geographical locations (e.g. Wuhan, China), animal species, or groups of people in disease and virus names in part to prevent social stigma . WHO finalised
6588-425: The 1890s through 1906, Tesla spent a great deal of his time and fortune on a series of projects trying to develop the transmission of electrical power without wires . It was an expansion of his idea of using coils to transmit power that he had been demonstrating in wireless lighting. He saw this as not only a way to transmit large amounts of power around the world but also, as he had pointed out in his earlier lectures,
6710-536: The 1892 merger of Edison and Thomson-Houston). The money Tesla made from licensing his AC patents made him independently wealthy and gave him the time and funds to pursue his own interests. In 1889, Tesla moved out of the Liberty Street shop Peck and Brown had rented and for the next dozen years worked out of a series of workshop/laboratory spaces in Manhattan . These included a lab at 175 Grand Street (1889–1892),
6832-585: The 1990s. Nikola Tesla was born into an ethnic Serb family in the village of Smiljan , within the Military Frontier , in the Austrian Empire (present-day Croatia ), on 10 July 1856. His father, Milutin Tesla (1819–1879), was a priest of the Eastern Orthodox Church . His father's brother Josif was a lecturer at a military academy who wrote several textbooks on mathematics. Tesla's mother, Georgina "Đuka" Mandić (1822–1892), whose father
6954-585: The Columbian Exposition Agriculture Hall, Tesla introduced his steam powered reciprocating electricity generator that he patented that year, something he thought was a better way to generate alternating current. Steam was forced into the oscillator and rushed out through a series of ports, pushing a piston up and down that was attached to an armature. The magnetic armature vibrated up and down at high speed, producing an alternating magnetic field . This induced alternating electric current in
7076-1059: The Continental Edison Company. Tesla began working in what was then a brand new industry, installing indoor incandescent lighting citywide in large scale electric power utility . The company had several subdivisions and Tesla worked at the Société Electrique Edison, the division in the Ivry-sur-Seine suburb of Paris in charge of installing the lighting system. There he gained a great deal of practical experience in electrical engineering. Management took notice of his advanced knowledge in engineering and physics and soon had him designing and building improved versions of generating dynamos and motors. They also sent him on to troubleshoot engineering problems at other Edison utilities being built around France and in Germany. In 1884, Edison manager Charles Batchelor , who had been overseeing
7198-529: The Edison Machine Works". Soon after leaving the Edison company, Tesla was working on patenting an arc lighting system, possibly the same one he had developed at Edison. In March 1885, he met with patent attorney Lemuel W. Serrell, the same attorney used by Edison, to obtain help with submitting the patents. Serrell introduced Tesla to two businessmen, Robert Lane and Benjamin Vail, who agreed to finance an arc lighting manufacturing and utility company in Tesla's name,
7320-586: The K-Index paper. The Tesla Index measured social isolation of scientists relative to their productivity, named after Nikola Tesla , whose work was hugely influential, while he remained a social recluse. People tweeted suggestions hashtagged #alternatesciencemetrics . In 2022, John Ioannidis authored a paper in The BMJ arguing that signatories of the Great Barrington Declaration about how to deal with
7442-478: The Nikola Tesla Company, set up to fund, develop, and market a variety of previous Tesla patents and inventions as well as new ones. Alfred Brown signed on, bringing along patents developed under Peck and Brown. The board was filled out with William Birch Rankine and Charles F. Coaney. It found few investors since the mid-1890s were a tough time financially, and the wireless lighting and oscillators patents it
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#17328586395577564-578: The Paris installation, was brought back to the United States to manage the Edison Machine Works , a manufacturing division situated in New York City, and asked that Tesla be brought to the United States as well. In June 1884, Tesla emigrated and began working almost immediately at the Machine Works on Manhattan 's Lower East Side , an overcrowded shop with a workforce of several hundred machinists, laborers, managing staff, and 20 "field engineers" struggling with
7686-481: The US military as a type of radio-controlled torpedo , but they showed little interest. Remote radio control remained a novelty until World War I and afterward, when a number of countries used it in military programs . Tesla took the opportunity to further demonstrate "Teleautomatics" in an address to a meeting of the Commercial Club in Chicago, while he was traveling to Colorado Springs , on 13 May 1899. From
7808-636: The WHO in the past. As of 10 March 2023, more than 6.88 million deaths had been attributed to COVID-19. The first confirmed death was in Wuhan on 9 January 2020. These numbers vary by region and over time, influenced by testing volume, healthcare system quality, treatment options, government response, time since the initial outbreak, and population characteristics, such as age, sex, and overall health. Multiple measures are used to quantify mortality. Official death counts typically include people who died after testing positive. Such counts exclude deaths without
7930-419: The WHO, US, European Union, and Australia. On 12 November 2022, the WHO released its Global Vaccine Market Report. The report indicated that "inequitable distribution is not unique to COVID-19 vaccines"; countries that are not economically strong struggle to obtain vaccines. On 14 November 2022, the first inhalable vaccine was introduced, developed by Chinese biopharmaceutical company CanSino Biologics , in
8052-521: The alternating current system he was already marketing. Westinghouse looked into getting a patent on a similar commutator-less, rotating magnetic field-based induction motor developed in 1885 and presented in a paper in March 1888 by Italian physicist Galileo Ferraris , but decided that Tesla's patent would probably control the market. In July 1888, Brown and Peck negotiated a licensing deal with George Westinghouse for Tesla's polyphase induction motor and transformer designs for $ 60,000 in cash and stock and
8174-423: The bankers" to try to collect future royalties. The advantages of having Westinghouse continue to champion the motor probably seemed obvious to Tesla and he agreed to release the company from the royalty payment clause in the contract. Six years later Westinghouse purchased Tesla's patent for a lump sum payment of $ 216,000 as part of a patent-sharing agreement signed with General Electric (a company created from
8296-566: The bid to light the Exposition with alternating current and it was a key event in the history of AC power, as the company demonstrated to the American public the safety, reliability, and efficiency of an alternating current system that was polyphase and could also supply the other AC and DC exhibits at the fair. A special exhibit space was set up to display various forms and models of Tesla's induction motor. The rotating magnetic field that drove them
8418-420: The bits of metal projected by his "electric gun", Tesla said, "The particles in the beam of force ... will travel much faster than such particles ... and they will travel in concentrations". In 1898, Tesla demonstrated a boat that used a coherer -based radio control —which he dubbed "telautomaton"—to the public during an electrical exhibition at Madison Square Garden . Tesla tried to sell his idea to
8540-448: The broad family of viruses known as coronaviruses . It is a positive-sense single-stranded RNA (+ssRNA) virus, with a single linear RNA segment. Coronaviruses infect humans, other mammals, including livestock and companion animals, and avian species. Human coronaviruses are capable of causing illnesses ranging from the common cold to more severe diseases such as Middle East respiratory syndrome (MERS, fatality rate ≈34%). SARS-CoV-2
8662-524: The centre of a major infection cluster in Germany, 15 per cent of a population sample tested positive for antibodies . Screening for COVID-19 in pregnant women in New York City , and blood donors in the Netherlands, found rates of positive antibody tests that indicated more infections than reported. Seroprevalence -based estimates are conservative as some studies show that persons with mild symptoms do not have detectable antibodies. Initial estimates of
8784-746: The city of Shanghai, China. For the first two years of the pandemic, no specific and effective treatment or cure was available. In 2021, the European Medicines Agency's (EMA) Committee for Medicinal Products for Human Use (CHMP) approved the oral antiviral protease inhibitor , Paxlovid (nirmatrelvir plus the HIV antiviral ritonavir ), to treat adult patients. FDA later gave it an EUA. Most cases of COVID-19 are mild. In these, supportive care includes medication such as paracetamol or NSAIDs to relieve symptoms (fever, body aches, cough), adequate intake of oral fluids and rest. Good personal hygiene and
8906-545: The coil. Later called the Tesla coil, it would be used to produce high- voltage , low- current , high frequency alternating-current electricity. He would use this resonant transformer circuit in his later wireless power work. On 30 July 1891, aged 35, Tesla became a naturalized citizen of the United States. In the same year, he patented his Tesla coil. After 1890, Tesla experimented with transmitting power by inductive and capacitive coupling using high AC voltages generated with his Tesla coil. He attempted to develop
9028-408: The company to lose contracts in some cities. Tesla's designs were never put into production, possibly because of technical improvements in incandescent street lighting or because of an installation deal that Edison made with an arc lighting company. Tesla had been working at the Machine Works for a total of six months when he quit. What event precipitated his leaving is unclear. It may have been over
9150-480: The cumulative number of infected individuals (including asymptomatic and undiagnosed infections and excluding vaccinated infected individuals). It is expressed in percentage points. Other studies refer to this metric as the infection fatality risk . In November 2020, a review article in Nature reported estimates of population-weighted IFRs for various countries, excluding deaths in elderly care facilities, and found
9272-468: The deal, quipping "Tesla, you don't understand our American humor". The size of the bonus in either story has been noted as odd since Machine Works manager Batchelor was stingy with pay and the company did not have that amount of cash (equal to $ 1,695,556 today) on hand. Tesla's diary contains just one comment on what happened at the end of his employment, a note he scrawled across the two pages covering 7 December 1884, to 4 January 1885, saying "Good By to
9394-464: The design of an electric motor the professor was demonstrating. But by his third year he was failing in school and never graduated, leaving Graz in December 1878. One biographer suggests Tesla was not studying and may have been expelled for gambling and womanizing. Tesla's family did not hear from him after he left school. There was a rumor among his classmates that he had drowned in the nearby river Mur but in January one of them ran into Tesla in
9516-441: The development of various vaccine platforms during early 2020. The initial focus of SARS-CoV-2 vaccines was on preventing symptomatic and severe illness. The COVID-19 vaccines are widely credited for their role in reducing the severity and death caused by COVID-19. As of March 2023, more than 5.5 billion people had received one or more doses (11.8 billion in total) in over 197 countries. The Oxford-AstraZeneca vaccine
9638-513: The eyes, nose, or mouth with unwashed hands. Those diagnosed with COVID-19 or who believe they may be infected are advised by healthcare authorities to stay home except to get medical care, call ahead before visiting a healthcare provider, wear a face mask before entering the healthcare provider's office and when in any room or vehicle with another person, cover coughs and sneezes with a tissue, regularly wash hands with soap and water and avoid sharing personal household items. A COVID-19 vaccine
9760-440: The forerunner of the modern-day IEEE (along with the Institute of Radio Engineers ). By the beginning of 1893, Westinghouse engineer Charles F. Scott and then Benjamin G. Lamme had made progress on an efficient version of Tesla's induction motor. Lamme found a way to make the polyphase system it would need compatible with older single-phase AC and DC systems by developing a rotary converter . Westinghouse Electric now had
9882-530: The fourth floor of 33–35 South Fifth Avenue (1892–1895), and sixth and seventh floors of 46 & 48 East Houston Street (1895–1902). Tesla and his hired staff conducted some of his most significant work in these workshops. In the summer of 1889, Tesla traveled to the 1889 Exposition Universelle in Paris and learned of Heinrich Hertz 's 1886–1888 experiments that proved the existence of electromagnetic radiation , including radio waves . In repeating and then expanding on these experiments Tesla tried powering
10004-496: The gender disparity in his sample. Of 14 female scientists, 11 had lower than predicted K-indices, while only one of the high-index scientists was female. On February 11, 2022, on Twitter, Neil Hall stated that he intended the Kardashian Index to be a “dig at metrics not Kardashians” and that “the entire premise is satire”. Many jocular indices of scientific productivity were proposed in the immediate aftermath of publication of
10126-474: The general public beginning in December 2020, made available through government and international programs such as COVAX , aiming to provide vaccine equity . Treatments include novel antiviral drugs and symptom control. Common mitigation measures during the public health emergency included travel restrictions , lockdowns , business restrictions and closures, workplace hazard controls , mask mandates , quarantines, testing systems, and contact tracing of
10248-618: The hazards of working with his circuit and single-node X-ray-producing devices. In his many notes on the early investigation of this phenomenon, he attributed the skin damage to various causes. He believed early on that damage to the skin was not caused by the Roentgen rays, but by the ozone generated in contact with the skin, and to a lesser extent, by nitrous acid . Tesla incorrectly believed that X-rays were longitudinal waves, such as those produced in waves in plasmas . These plasma waves can occur in force-free magnetic fields . On 11 July 1934,
10370-482: The help of partners to finance and market his ideas, Tesla set up laboratories and companies in New York to develop a range of electrical and mechanical devices. His AC induction motor and related polyphase AC patents, licensed by Westinghouse Electric in 1888, earned him a considerable amount of money and became the cornerstone of the polyphase system which that company eventually marketed. Attempting to develop inventions he could patent and market, Tesla conducted
10492-657: The infected. The pandemic caused severe social and economic disruption around the world, including the largest global recession since the Great Depression . Widespread supply shortages , including food shortages , were caused by supply chain disruptions and panic buying . Reduced human activity led to an unprecedented temporary decrease in pollution . Educational institutions and public areas were partially or fully closed in many jurisdictions, and many events were cancelled or postponed during 2020 and 2021. Telework became much more common for white-collar workers as
10614-439: The issue of respiratory failure. Existing drugs such as hydroxychloroquine , lopinavir/ritonavir , and ivermectin are not recommended by US or European health authorities, as there is no good evidence they have any useful effect. The antiviral remdesivir is available in the US, Canada, Australia, and several other countries, with varying restrictions; however, it is not recommended for use with mechanical ventilation, and
10736-576: The majority of the unreported 9.5 million deaths believed to be direct deaths due the virus, rather than indirect deaths. Some deaths were because people with other conditions could not access medical services . A December 2022 WHO study estimated excess deaths from the pandemic during 2020 and 2021, again concluding ≈14.8 million excess early deaths occurred, reaffirming and detailing their prior calculations from May as well as updating them, addressing criticisms. These numbers do not include measures like years of potential life lost and may make
10858-449: The next month, on 17 April 1879, at the age of 60 after an unspecified illness. During the rest of the year Tesla taught a large class of students in his old school in Gospić. In January 1880, two of Tesla's uncles put together enough money to help him leave Gospić for Prague , where he was to study. He arrived too late to enroll at Charles-Ferdinand University ; he had never studied Greek ,
10980-495: The official names COVID-19 and SARS-CoV-2 on 11 February 2020. Tedros Adhanom Ghebreyesus explained: CO for corona , VI for virus , D for disease and 19 for when the outbreak was first identified (31 December 2019). WHO additionally uses "the COVID-19 virus" and "the virus responsible for COVID-19" in public communications. WHO named variants of concern and variants of interest using Greek letters . The initial practice of naming them according to where
11102-427: The outbreak as having become a pandemic on 11 March. COVID-19 symptoms range from asymptomatic to deadly, but most commonly include fever, sore throat , nocturnal cough , and fatigue. Transmission of the virus is often through airborne particles . Mutations have produced many strains (variants) with varying degrees of infectivity and virulence . COVID-19 vaccines were developed rapidly and deployed to
11224-407: The pandemic 2021's leading cause of death . The time between symptom onset and death ranges from 6 to 41 days, typically about 14 days. Mortality rates increase as a function of age. People at the greatest mortality risk are the elderly and those with underlying conditions. The infection fatality ratio (IFR) is the cumulative number of deaths attributed to the disease divided by
11346-491: The pandemic evolved. Misinformation circulated through social media and mass media , and political tensions intensified . The pandemic raised issues of racial and geographic discrimination , health equity , and the balance between public health imperatives and individual rights . The WHO ended the PHEIC for COVID-19 on 5 May 2023. The disease has continued to circulate, but as of 2024, experts were uncertain as to whether it
11468-400: The patent, both in 1888, came at the time of extreme competition between electric companies. The three big firms, Westinghouse, Edison, and Thomson-Houston Electric Company , were trying to grow in a capital-intensive business while financially undercutting each other. There was even a " war of currents " propaganda campaign going on, with Edison Electric claiming their direct current system
11590-520: The patent. Physicist William Arnold Anthony (who tested the motor) and Electrical World magazine editor Thomas Commerford Martin arranged for Tesla to demonstrate his AC motor on 16 May 1888 at the American Institute of Electrical Engineers . Engineers working for the Westinghouse Electric & Manufacturing Company reported to George Westinghouse that Tesla had a viable AC motor and related power system—something Westinghouse needed for
11712-415: The population's age structure and the age-specific pattern of infections. There have also been reviews that have compared the fatality rate of this pandemic with prior pandemics, such as MERS-CoV. For comparison the infection mortality rate of seasonal flu in the United States is 0.1%, which is 13 times lower than COVID-19. Another metric in assessing death rate is the case fatality ratio (CFR), which
11834-447: The possibility of wireless communication with his devices. Tesla tried to put these ideas to practical use in his unfinished Wardenclyffe Tower project, an intercontinental wireless communication and power transmitter, but ran out of funding before he could complete it. After Wardenclyffe, Tesla experimented with a series of inventions in the 1910s and 1920s with varying degrees of success. Having spent most of his money, Tesla lived in
11956-630: The priesthood), promised to send him to the best engineering school if he recovered from the illness. Tesla later said that he had read Mark Twain 's earlier works while recovering from his illness. The next year Tesla evaded conscription into the Austro-Hungarian Army in Smiljan by running away southeast of Lika to Tomingaj , near Gračac . There he explored the mountains wearing hunter's garb. Tesla said that this contact with nature made him stronger, both physically and mentally. He enrolled at
12078-458: The risk of dying from seasonal influenza . In December 2020, a systematic review and meta-analysis estimated that population-weighted IFR was 0.5% to 1% in some countries (France, Netherlands, New Zealand, and Portugal), 1% to 2% in other countries (Australia, England, Lithuania, and Spain), and about 2.5% in Italy. This study reported that most of the differences reflected corresponding differences in
12200-496: The same infection may have different symptoms, and their symptoms may change over time. Three common clusters of symptoms have been identified: one respiratory symptom cluster with cough, sputum , shortness of breath, and fever; a musculoskeletal symptom cluster with muscle and joint pain, headache, and fatigue; a cluster of digestive symptoms with abdominal pain, vomiting, and diarrhoea. In people without prior ear, nose, and throat disorders, loss of taste combined with loss of smell
12322-439: The scientific quality or scientific impact. Nikola Tesla Nikola Tesla ( / ˈ n ɪ k ə l ə ˈ t ɛ s l ə / ; Serbian Cyrillic : Никола Тесла , [nǐkola têsla] ; 10 July 1856 – 7 January 1943) was a Serbian-American engineer, futurist , and inventor. He is known for his contributions to the design of the modern alternating current (AC) electricity supply system. Born and raised in
12444-400: The signatories had no Google Scholar pages. The K-index suggests that the number of citations of a given scientist is comparable to their scientific value. This assumption has been criticized. The proposal of the K-Index has been interpreted as a criticism to the assumption that scientists should have a social media impact at all, while in reality, social media footprint has no correlation to
12566-464: The task of building the large electric utility in that city. As in Paris, Tesla was working on troubleshooting installations and improving generators. Historian W. Bernard Carlson notes Tesla may have met company founder Thomas Edison only a couple of times. One of those times was noted in Tesla's autobiography where, after staying up all night repairing the damaged dynamos on the ocean liner SS Oregon , he ran into Batchelor and Edison, who made
12688-411: The time from symptom onset to death has ranged from two to eight weeks. Prolonged prothrombin time and elevated C-reactive protein levels on admission to the hospital are associated with severe course of COVID-19 and with a transfer to intensive care units (ICU). Between 5% and 50% of COVID-19 patients experience long COVID , a condition characterised by long-term consequences persisting after
12810-457: The time to be a short-distance phenomenon that seemed to die out in less than a mile. Tesla noted that, even if theories on radio waves were true, they were totally worthless for his intended purposes since this form of "invisible light" would diminish over a distance just like any other radiation and would travel in straight lines right out into space, becoming "hopelessly lost". COVID-19 pandemic The COVID-19 pandemic (also known as
12932-448: The town of Maribor and reported that encounter to Tesla's family. It turned out Tesla had been working there as a draftsman for 60 florins per month. In March 1879, Milutin finally located his son and tried to convince him to return home and take up his education in Prague. Tesla returned to Gospić later that month when he was deported for not having a residence permit. Tesla's father died
13054-694: The typical convalescence period of the disease. The most commonly reported clinical presentations are fatigue and memory problems, as well as malaise , headaches, shortness of breath , loss of smell, muscle weakness , low fever and cognitive dysfunction . Many countries attempted to slow or stop the spread of COVID-19 by recommending, mandating or prohibiting behaviour changes, while others relied primarily on providing information. Measures ranged from public advisories to stringent lockdowns. Outbreak control strategies are divided into elimination and mitigation. Experts differentiate between elimination strategies (known as " zero-COVID ") that aim to completely stop
13176-440: The utility was up and running in 1886, they decided that the manufacturing side of the business was too competitive and opted to simply run an electric utility. They formed a new utility company, abandoning Tesla's company and leaving the inventor penniless. Tesla even lost control of the patents he had generated, since he had assigned them to the company in exchange for stock. He had to work at various electrical repair jobs and as
13298-543: The variants were identified (e.g. Delta began as the " Indian variant") is no longer common. A more systematic naming scheme reflects the variant's PANGO lineage (e.g., Omicron 's lineage is B.1.1.529) and is used for other variants. SARS-CoV-2 is a virus closely related to bat coronaviruses , pangolin coronaviruses, and SARS-CoV . The first known outbreak (the 2019–2020 COVID-19 outbreak in mainland China ) started in Wuhan , Hubei, China, in December 2019. Many early cases were linked to people who had visited
13420-492: The wire coils located adjacent. It did away with the complicated parts of a steam engine/generator, but never caught on as a feasible engineering solution to generate electricity. In 1893, Edward Dean Adams , who headed the Niagara Falls Cataract Construction Company , sought Tesla's opinion on what system would be best to transmit power generated at the falls. Over several years, there had been
13542-400: Was able to perform integral calculus in his head, which prompted his teachers to believe that he was cheating. He finished a four-year term in three years, graduating in 1873. After graduating Tesla returned to Smiljan but soon contracted cholera , was bedridden for nine months and was near death multiple times. In a moment of despair, Tesla's father (who had originally wanted him to enter
13664-443: Was accidentally released from a laboratory have been proposed, as of 2021 these were not supported by evidence. Official "case" counts refer to the number of people who have been tested for COVID-19 and whose test has been confirmed positive according to official protocols whether or not they experienced symptomatic disease. Due to the effect of sampling bias , studies which obtain a more accurate number by extrapolating from
13786-435: Was also an Eastern Orthodox Church priest, had a talent for making home craft tools and mechanical appliances and the ability to memorize Serbian epic poems . Đuka had never received a formal education. Tesla credited his eidetic memory and creative abilities to his mother's genetics and influence. Tesla was the fourth of five children. He had three sisters, Milka, Angelina, and Marica, and an older brother named Dane, who
13908-529: Was better and safer than the Westinghouse alternating current system and Thomson-Houston sometimes siding with Edison. Competing in this market meant Westinghouse would not have the cash or engineering resources to develop Tesla's motor and the related polyphase system right away. Two years after signing the Tesla contract, Westinghouse Electric was in trouble. The near collapse of Barings Bank in London triggered
14030-536: Was explained through a series of demonstrations including an Egg of Columbus that used the two-phase coil found in an induction motor to spin a copper egg making it stand on end. Tesla visited the fair for a week during its six-month run to attend the International Electrical Congress and put on a series of demonstrations at the Westinghouse exhibit. A specially darkened room had been set up where Tesla showed his wireless lighting system, using
14152-404: Was killed in a horse-riding accident when Tesla was aged six or seven. In 1861, Tesla attended primary school in Smiljan where he studied German, arithmetic, and religion. In 1862, the Tesla family moved to the nearby town of Gospić , where Tesla's father worked as parish priest. Nikola completed primary school, followed by middle school. In 1870, Tesla moved to Karlovac to attend high school at
14274-608: Was not functional, so he worked as a draftsman in the Central Telegraph Office instead. Within a few months, the Budapest Telephone Exchange became functional, and Tesla was allocated the chief electrician position. During his employment, Tesla made many improvements to the Central Station equipment and claimed to have perfected a telephone repeater or amplifier , which was never patented nor publicly described. In 1882, Tivadar Puskás got Tesla another job in Paris with
14396-475: Was set up to market never panned out. The company handled Tesla's patents for decades to come. In the early morning hours of 13 March 1895, the South Fifth Avenue building that housed Tesla's lab caught fire. It started in the basement of the building and was so intense Tesla's 4th-floor lab burned and collapsed into the second floor. The fire not only set back Tesla's ongoing projects, but it also destroyed
14518-457: Was still a pandemic. Pandemics and their ends are not well-defined, and whether or not one has ended differs according to the definition used. As of 24 November 2024, COVID-19 has caused 7,075,455 confirmed deaths. The COVID-19 pandemic ranks as the fifth- deadliest pandemic or epidemic in history . In epidemiology , a pandemic is defined as "an epidemic occurring over a very wide area, crossing international boundaries, and usually affecting
14640-455: Was stuck in development. Westinghouse was paying a $ 15,000-a-year guaranteed royalty even though operating examples of the motor were rare and polyphase power systems needed to run it was even rarer. In early 1891, George Westinghouse explained his financial difficulties to Tesla in stark terms, saying that, if he did not meet the demands of his lenders, he would no longer be in control of Westinghouse Electric and Tesla would have to "deal with
14762-502: Was the most widely used. According to a June 2022 study, COVID-19 vaccines prevented an additional 14.4 million to 19.8 million deaths in 185 countries and territories from 8 December 2020 to 8 December 2021. On 8 November 2022, the first recombinant protein-based COVID-19 vaccine (Novavax's booster Nuvaxovid ) was authorised for use in adults in the United Kingdom. It has subsequently received endorsement/authorisation from
14884-515: Was turned on, the lamps or tubes, which had no wires connected to them, but lay on a table between the suspended plates, or which might be held in the hand in almost any part of the room, were made luminous. These were the same experiments and the same apparatus shown by Tesla in London about two years previous, "where they produced so much wonder and astonishment". During his presentation at the International Electrical Congress in
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