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Health Service Executive Cyberattack
On 14 May 2021, the Health Service Executive (HSE) of the Republic of Ireland suffered a major ransomware cyberattack that caused all of its IT systems nationwide to be shut down. It was the most significant cybercrime attack on an Irish state agency. Bloomberg News reported that the attackers used the Conti ransomware. The group responsible was identified as a criminal gang known as Wizard Spider, believed to be operating from Russia. The same group is believed to have attacked the Department of Health with a similar cyberattack. On 19 May, the Financial Times reviewed private data for twelve individuals which had appeared online as a result of the breach, with admission records and test results present in one case.
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  • 27 Oct 2022
Topic Review
Rheinmetall 120 Mm Gun
The Rheinmetall 120 mm gun is a smoothbore tank gun designed and produced by the West German Rheinmetall-DeTec AG company, developed in response to Soviet advances in armor technology and development of new armored threats. Production began in 1974, with the first version of the gun, known as the L/44 as it was 44 calibers long, used on the German Leopard 2 tank and soon produced under license for the American M1A1 Abrams and other tanks. The American version, the M256, uses a coil spring recoil system instead of a hydraulic system. The 120-millimeter (4.7 in) gun has a length of 5.28 meters (17.3 ft), and the gun system weighs approximately 3,317 kilograms (7,313 lb). By 1990, the L/44 was not considered powerful enough to deal with future Soviet armour, which stimulated an effort by Rheinmetall to develop a better main armament. This first involved a 140-millimeter (5.5 in) tank gun named Neue Panzerkanone 140 ("new tank gun 140"), but later turned into a compromise which led to the development of an advanced 120 mm gun, the L/55, based on the same internal geometry as the L/44 and installed in the same breech and mount. The L/55 is 1.32 meters (4.3 ft) longer, giving increased muzzle velocity to ammunition fired through it. As the L/55 retains the same barrel geometry, it can fire the same ammunition as the L/44. This gun was retrofitted into German and Dutch Leopard 2s, and chosen as the main gun of the Spanish Leopard 2E and the Greek Leopard 2HEL. It was tested on the British Challenger 2 as a potential replacement for its current weapon, the rifled L30 120 mm cannon. A variety of ammunition has been developed for use by tanks with guns based on Rheinmetall's original L/44 design. This includes a series of kinetic energy penetrators, such as the American M829 series, and high explosive anti-tank warheads. Recent ammunition includes a range of anti-personnel rounds and demolition munitions. The LAHAT, developed in Israel, is a gun-launched missile which has received interest from Germany and other Leopard 2 users, and is designed to defeat both land armour and combat helicopters. The Israelis also introduced a new anti-personnel munition which limits collateral damage by controlling the fragmentation of the projectile.
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Topic Review
Fossil Fuels Lobby
"Fossil fuels lobby" is a term used to label the paid representatives of large fossil fuel (oil, gas, coal) and electric utilities corporations who attempt to influence governmental policy. So-called Big Oil companies such as ExxonMobil, Royal Dutch Shell, BP, Total S.A., Chevron Corporation, and ConocoPhillips are amongst the largest corporations associated with the fossil fuels lobby. General Electric, Southern Company, First Energy, and the Edison Electric Institute are also among the most influential electric utilities corporations. By sector, "Energy/Nat Resource" comes fifth, behind "Misc Business", "Finance/Insur/RealEst", Health and "Communic/Electronics".
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Messerschmitt Me 410
The Messerschmitt Me 410 Hornisse (Hornet) was a German heavy fighter and Schnellbomber used by the Luftwaffe during World War II. Though an incremental improvement of the Me 210, it had a new wing plan, longer fuselage and engines of greater power. The changes were significant enough for the aircraft to be renamed the Me 410.
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Topic Review
Russia under Vladimir Putin
Vladimir Putin has served three terms and is currently in a fourth as President of Russia (2000–2004, 2004–2008, 2012–2018 and May 2018 to present) and was Acting President from 1999 to 2000, succeeding Boris Yeltsin after Yeltsin's resignation. Putin was also Prime Minister for three months in 1999 and served a full term from 2008 to 2012. During Putin's presidency, he has been a member of the Unity party and the United Russia party. He is also affiliated with the People’s Front, a group of supporters that Putin organized in 2011 to help improve the public's perception of United Russia. His political ideology, priorities and policies are sometimes referred to as Putinism (Russian: путинизм). Putin has enjoyed very high domestic approval ratings and in 2007 was Time magazine's Person of the Year. In 2015, he was designated No. 1 in Time 100, Time magazine's list of the top 100 most influential people in the world. In 2013, 2014, 2015 and 2016, he was designated No. 1 on the Forbes list of The World’s Most Powerful People. The Russian economy and standard of living grew rapidly during the early period of Putin's regime, fueled largely by a boom in the oil industry. However, lower oil prices and sanctions for Russia's annexation of Crimea led to recession and stagnation in 2015 that has persisted into the present day.. Political freedoms have been sharply curtailed, leading to widespread condemmnation from human rights groups.
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Topic Review
Resonance
Resonance describes the phenomenon of increased amplitude that occurs when the frequency of an applied periodic force (or a Fourier component of it) is equal or close to a natural frequency of the system on which it acts. When an oscillating force is applied at a resonant frequency of a dynamic system, the system will oscillate at a higher amplitude than when the same force is applied at other, non-resonant frequencies. Frequencies at which the response amplitude is a relative maximum are also known as resonant frequencies or resonance frequencies of the system. Small periodic forces that are near a resonant frequency of the system have the ability to produce large amplitude oscillations in the system due to the storage of vibrational energy. Resonance phenomena occur with all types of vibrations or waves: there is mechanical resonance, Orbital resonance, acoustic resonance, electromagnetic resonance, nuclear magnetic resonance (NMR), electron spin resonance (ESR) and resonance of quantum wave functions. Resonant systems can be used to generate vibrations of a specific frequency (e.g., musical instruments), or pick out specific frequencies from a complex vibration containing many frequencies (e.g., filters). The term resonance (from Latin resonantia, 'echo', from resonare, 'resound') originated from the field of acoustics, particularly the sympathetic resonance observed in musical instruments, e.g., when one string starts to vibrate and produce sound after a different one is struck.
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Topic Review
Bombardier CRJ200
The Bombardier CRJ100 and CRJ200 (formerly known as the Canadair CRJ100 and CRJ200) are a family of regional airliners designed and manufactured by Bombardier. The CRJ had the distinction of marking Canada's entry into the civil jet industry. It was based on the Canadair Challenger business jet. An initial effort to produce an enlarged 36-seat version of the aircraft, known as the Challenger 610E, was terminated during 1981. Shortly after Canadair's privatisation and sale to Bombardier, work on a stretched derivative was reinvigorated; during early 1989, the Canadair Regional Jet program was formally launched. On 10 May 1991, the first of three CRJ100 prototypes conducted its maiden flight. The type first entered service during the following year with its launch customer, Germany airline Lufthansa. The initial variant, the CRJ100, was soon joined by another model, designated as the CRJ200. It was largely identical to the CRJ100, except for the installation of more efficient turbofan engines, which gave the aircraft lower fuel consumption, increased cruise altitude and cruise speed. During the 1990s, various additional versions and models of the type were developed and put into service. During the late 1990s, a substantially enlarged derivative of the airliner, referred to as the CRJ700, was developed; it was soon joined by the even larger CRJ900 and CRJ1000. During 2006, production of both the CRJ100 and CRJ200 came to an end; the majority of produced airliners have remained in revenue service to date. Additionally, several airlines have modernised their fleets to support extended service.
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Topic Review
HIV Vaccine Development
An HIV vaccine can be either a preventive vaccine or a therapeutic vaccine, which means it can either protect individuals from being infected with HIV or treat HIV-infected individuals. And it can either induce an immune response against HIV (active vaccination approach) or consist of preformed antibodies against HIV (passive vaccination approach). There is currently no licensed HIV vaccine on the market, but multiple research projects are trying to find an effective vaccine. Evidence observed from humans shows that a vaccine may be possible: Some, but certainly not all, HIV-infected individuals naturally produce broadly neutralizing antibodies which keep the virus suppressed, and these people remain asymptomatic for decades. Potential broadly neutralizing antibodies have been cloned in the laboratory (monoclonal antibodies) and are being tested in passive vaccination clinical trials. Many trials have shown no efficacy, but one HIV vaccine regimen, RV 144, has been shown to prevent HIV in some individuals in Thailand. The urgency of the search for a vaccine against HIV stems from the AIDS-related death toll of over 35 million people since 1981. In 2002, AIDS became the primary cause of death due to an infectious agent in Africa. Alternative medical treatments to a vaccine exist. For the treatment of HIV-infected individuals, highly active antiretroviral therapy (HAART) medication has been demonstrated to provide many benefits to HIV-infected individuals, including improved health, increased lifespan, control of viremia, and prevention of transmission to babies and partners. HAART must be taken lifelong without interruption to be effective, and cannot cure HIV. Options for the prevention of HIV infection in HIV-uninfected individuals include safer sex (for example condom use), antiretroviral strategies (pre-exposure prophylaxis and post-exposure prophylaxis) and medical male circumcision. Vaccination has proved a powerful public health tool in vanquishing other diseases, and an HIV vaccine is generally considered as the most likely, and perhaps the only way by which the HIV pandemic can be halted. However, HIV remains a challenging target for a vaccine.
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Topic Review
Stinger
In medicine, a stinger, also called a burner or nerve pinch injury, is a neurological injury suffered by athletes, mostly in high-contact sports such as ice hockey, rugby, American football, and wrestling. The spine injury is characterized by a shooting or stinging pain that travels down one arm, followed by numbness and weakness in the parts of the arms, including the biceps, deltoid, and spinati muscles. Many athletes in contact sports have suffered stingers, but they are often unreported to medical professionals. Anyone who experiences significant trauma to his or her head or neck needs immediate medical evaluation for the possibility of a spinal injury. In fact, it's safest to assume that trauma victims have a spinal injury until proven otherwise because: (1) The time between injury and treatment can be critical in determining the extent of complications and the amount of recovery. (2) A serious spinal injury is not always immediately obvious. If it is not recognized, more severe injury may occur. (3) Numbness or paralysis may develop immediately or come on gradually as bleeding or swelling occurs in or around the spinal cord.
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Topic Review
List of Maglev Train Proposals
This is a list of proposed maglev trains worldwide. Some proposals may have been rejected.
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