Plastics are a wide range of synthetic or semi-synthetic materials that use polymers as a main ingredient. Their plasticity makes it possible for plastics to be moulded, extruded or pressed into solid objects of various shapes. This adaptability, plus a wide range of other properties, such as being lightweight, durable, flexible, and inexpensive to produce, has led to its widespread use. Plastics typically are made through human industrial systems. Most modern plastics are derived from fossil fuel-based chemicals like natural gas or petroleum; however, recent industrial methods use variants made from renewable materials, such as corn or cotton derivatives.9.2 billion tonnes of plastic are estimated to have been made between 1950 and 2017. More than half this plastic has been produced since 2004. In 2020, 400 million tonnes of plastic were produced. If global trends on plastic demand continue, it is estimated that by 2050 annual global plastic production will reach over 1,100 million tonnes. The success and dominance of plastics starting in the early 20th century has caused widespread environmental problems, due to their slow decomposition...

A ballpoint pen, also known as a biro (British English), ball pen (Hong Kong, Indian and Philippine English), or dot pen (Nepali) is a pen that dispenses ink (usually in paste form) over a metal ball at its point, i.e. over a "ball point". The metal commonly used is steel, brass, or tungsten carbide. The design was conceived and developed as a cleaner and more reliable alternative to dip pens and fountain pens, and it is now the world's most-used writing instrument; millions are manufactured and sold daily. It has influenced art and graphic design and spawned an artwork genre. Some pen manufacturers produce designer ballpoint pens for the high-end and collectors' markets. History Origins The concept of using a "ball point" within a writing instrument to apply ink to paper has existed since the late 19th century. In these inventions, the ink was placed in a thin tube whose end was blocked by a tiny ball, held so that it could not slip into the tube or...

Aerodynamics, from Ancient Greek: ἀήρ aero (air) + Ancient Greek: δυναμική (dynamics), is the study of the motion of air, particularly when affected by a solid object, such as an airplane wing. It involves topics covered in the field of fluid dynamics and its subfield of gas dynamics. The term aerodynamics is often used synonymously with gas dynamics, the difference being that "gas dynamics" applies to the study of the motion of all gases, and is not limited to air. The formal study of aerodynamics began in the modern sense in the eighteenth century, although observations of fundamental concepts such as aerodynamic drag were recorded much earlier. Most of the early efforts in aerodynamics were directed toward achieving heavier-than-air flight, which was first demonstrated by Otto Lilienthal in 1891. Since then, the use of aerodynamics through mathematical analysis, empirical approximations, wind tunnel experimentation, and computer simulations has formed a rational basis for the development of heavier-than-air flight and a number of other technologies. Recent work in aerodynamics has focused on issues related...

Polymer physics is the field of physics that studies polymers, their fluctuations, mechanical properties, as well as the kinetics of reactions involving degradation and polymerisation of polymers and monomers respectively.While it focuses on the perspective of condensed matter physics, polymer physics is originally a branch of statistical physics. Polymer physics and polymer chemistry are also related with the field of polymer science, where this is considered the applicative part of polymers. Polymers are large molecules and thus are very complicated for solving using a deterministic method. Yet, statistical approaches can yield results and are often pertinent, since large polymers (i.e., polymers with many monomers) are describable efficiently in the thermodynamic limit of infinitely many monomers (although the actual size is clearly finite). Thermal fluctuations continuously affect the shape of polymers in liquid solutions, and modeling their effect requires using principles from statistical mechanics and dynamics. As a corollary, temperature strongly affects the physical behavior of polymers in solution, causing phase transitions, melts, and so on...

The flintlock mechanism is a type of lock used on muskets, rifles, and pistols from the early 17th to the mid-19th century. It is commonly referred to as a "flintlock" (without the word mechanism), though that term is also commonly used for the weapons themselves as a whole, and not just the lock mechanism. The flintlock mechanism, also known as the true flintlock, was developed in France in the early 17th century. It quickly replaced earlier technologies, such as the matchlock and wheellock and the earlier flintlocks. It continued to be in common use for over two centuries, until it was finally replaced by the percussion lock. History Flintlock firing mechanisms made their appearance in the 16th century in the form of the snaplock, the snaphance, the miquelet, and the doglock. The so-called true flintlock was developed in France in the early 17th century. Though its exact origins are not known, credit for the development of the true flintlock is usually given to Marin le Bourgeoys, an artist, gunsmith, luthier, and inventor from Normandy, France. Marin le Bourgeoys's basic design became the standard for flintlocks...

Paris (French pronunciation: ​[paʁi] (listen)) is the capital and most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), making it the 34th most densely populated city in the world in 2020. Since the 17th century, Paris has been one of the world's major centres of finance, diplomacy, commerce, fashion, gastronomy, science, and arts, and has sometimes been referred to as the capital of the world or City of Lights. The City of Paris is the centre of the region and province of Île-de-France, or Paris Region, with an estimated population of 12 262 544 in 2019, or about 19% of the population of France. The Paris Region had a GDP of €739 billion ($743 billion) in 2019, which is the highest of Europe. According to the Economist Intelligence Unit Worldwide Cost of Living Survey, in 2021 Paris was the city with the second-highest cost of living in the world, tied with Singapore, and after Tel Aviv....

Emmanuel Jean-Michel Frédéric Macron (French: [emanɥɛl ʒɑ̃ miʃɛl fʁedeʁik makʁɔ̃]; born 21 December 1977) is a French politician who has been serving as the president of France since 14 May 2017. Born in Amiens, Macron studied philosophy at Paris Nanterre University, later completing a master's degree in public affairs at Sciences Po and graduating from the École nationale d'administration in 2004. He worked as a senior civil servant at the Inspectorate General of Finances and later became an investment banker at Rothschild & Co. Macron was appointed a deputy secretary general by President François Hollande shortly after his election in May 2012, making Macron one of Hollande's senior advisers. He was later appointed to the French cabinet as Minister of the Economy, Industry and Digital Affairs in August 2014 by prime minister Manuel Valls. In this role, Macron championed a number of business-friendly reforms. He resigned from the cabinet in August 2016, launching a campaign for the 2017 French presidential election. Although Macron...

Paul Francis Pelosi Sr. (born April 15, 1940) is an American businessman who owns and operates Financial Leasing Services, Inc., a San Francisco-based real estate and venture capital investment and consulting firm. He was the owner of the Sacramento Mountain Lions of the United Football League. He is married to Nancy Pelosi, the current Speaker of the United States House of Representatives. Early life Pelosi was born and raised in San Francisco, the youngest in a family of three boys. His father was John Pelosi, a wholesale pharmacist. He attended St. Ignatius High School and graduated from Malvern Preparatory School in Pennsylvania. He earned a bachelor of science (BS) in foreign service at Georgetown University, during which he met his future wife, Nancy D'Alesandro, who was attending a Roman Catholic women's college, Trinity College, in Washington, D.C. He earned an MBA from the Stern School of Business at New York University. He has been the chair of the Foreign Service Board at Georgetown since 2009. Career Pelosi founded...

Zooniverse is a citizen science web portal owned and operated by the Citizen Science Alliance. It is home to some of the Internet's largest, most popular and most successful citizen science projects. The organization grew from the original Galaxy Zoo project and now hosts dozens of projects which allow volunteers to participate in crowdsourced scientific research. It has headquarters at Oxford University and the Adler Planetarium. Unlike many early internet-based citizen science projects (such as SETI@home) which used spare computer processing power to analyse data, known as volunteer computing, Zooniverse projects require the active participation of human volunteers to complete research tasks. Projects have been drawn from disciplines including astronomy, ecology, cell biology, humanities, and climate science.As of 14 February 2014, the Zooniverse community consisted of more than 1 million registered volunteers. By March 2019, that number had reportedly risen to 1.6 million. The volunteers are often collectively referred to as "Zooites". The data collected...

The Academy of Motion Picture Arts and Sciences says it will require films competing for best picture to meet criteria aimed at fostering a more inclusive Hollywood.