Science Fair Project Encyclopedia
History of science
Modern science is a body of verifiable empirical knowledge, a global community of scholars, and a set of techniques for investigating the universe known as the scientific method. The history of science traces these phenomena and their pre-cursors back in time, all the way into human prehistory.
The Scientific Revolution saw the inception of the modern scientific method to guide the evaluation of knowledge. This change is considered to be so fundamental that older inquiries are known as pre-scientific. Still, many place ancient natural philosophy clearly within the scope of the history of science.
The history of mathematics, the history of technology, and the history of philosophy are covered in different articles. Mathematics is closely related to, but distinct from science (at least in the modern conception). Technology concerns the creative process of designing useful objects and systems, which differs from the search for empirical truth. Philosophy differs from science in that, while both the natural and the social sciences attempt to base their theories on established fact, philosophy also enquires about other areas of knowledge, notably ethics. In practice, each of these fields is heavily used by the others as an external tool.
Theories and sociology of the history of science
Main article: Theories and sociology of the history of science
Much of the study of the history of science has been devoted to answering questions about what science is, how it functions, and whether it exhibits large-scale patterns and trends. The sociology of science in particular has focused on the ways in which scientists work, looking closely at the ways in which they "produce" and "construct" scientific knowledge. Since the 1960s, a common trend in the study of the sociology and history of science (science studies) has been to emphasize the "human component" to scientific knowledge, and to de-emphasize the view that scientific data is self-evident, value-free, and context-free.
A major subject of concern and controversy in the philosophy of science has been to inquire about the nature of theory change in science. Three philosophers in particular who represent the primary poles in this debate have been Karl Popper, who argued that scientific knowledge is progressive and cumulative; Thomas Kuhn, who argued that scientific knowledge moves through "paradigm shifts" and is not necessarily progressive; and Paul Feyerabend, who argued that scientific knowledge is not cumulative or progressive, and that there can be no demarcation between science and any other form of investigation.
Since the publication of Kuhn's The Structure of Scientific Revolutions in 1962, there has been much debate in the academic community over the meaning and objectivity of "science." Often, but not always, a conflict over the "truth" of science has split along the lines of those in the scientific community and those in the social sciences or humanities (for example, the "Science wars").
Main article : Pre-experimental science
In the West, from antiquity up to the time of the Scientific Revolution, inquiry into the workings of the universe was known as natural philosophy, and those engaged in it were known as natural philosophers. This included some fields of study which are no longer considered scientific). An account of the development of (natural) philosophy from ancient times until recent times can be found in Bertrand Russell's History of Philosophy. In many cases, systematic learning about the natural world was a direct outgrowth of religion, often as a project of a particular religious community.
One important feature of "pre-scientific" inquiry (whether in the West or elsewhere) was reluctance to engage in experiment. For example, Aristotle, one of the most prolific natural philosophers of antiquity, made countless observations of nature, especially the habits and attributes of plants and animals in the world around him. He focused on categorizing, and made many observations on the large-scale workings of the universe, which led to the development of a comprehensive theory of physics (see Physics (Aristotle)). Yet, until the period of the Scientific Revolution, these theories were never really tested experimentally. At the time, the utility of experiment was unproven. Some believed that setting up artificial conditions in an experiment could never produce results that would describe nature as it was in the world around them.
In prehistoric times, advice and knowledge was passed from generation to generation in an oral tradition. The development of writing enabled knowledge to be stored and communicated across generations with much greater fidelity. Combined with the development of agriculture, which allowed for a surplus of food, it became possible for early civilizations to develop and more time to be devoted to tasks other than survival, such as the search for knowledge for knowledge's sake.
Many ancient civilizations collected astronomical information in a systematic manner through simple observation. Though they had no knowledge of the real physical structure of the planets and stars, many theoretical explanations were proposed.
Some basic facts about internal human anatomy were known in some places, and alchemy was practiced in several civilizations. Considerable observation of macrobiotic flora and fauna was also possible.
The Middle Ages
Main article: History of science in the Middle Ages
The Middle Ages: Western World
With the loss of the Western Roman Empire, much of Europe lost contact with the knowledge of the past. Because of this regression in knowledge, the long period that followed is also known as the Dark Ages. While the Byzantine Empire still held learning centers such as Alexandria and Constantinople, Western Europes knowledge was concentrated in monasteries until the development of medieval universities in the 12th and 13th centuries. Initially these universities were organized to only teach theology, but people like Roger Bacon encouraged teaching of the sciences. Scientific teaching of the period was based upon copies of ancient texts that remained in Western Europe, and is known as the philosophic school of scholasticism. The rise of Christianity saw a strange paradox: classical Greek philosophy (along with Greek and Roman art, literature and religious iconography) was suppressed while at the same time it was safeguarded.
See Also: Renaissance
The Renaissance was instigated by rediscovery of the works of ancient philosophers and an intellectual revitalization of Europe. This provided a solid foundation for all future scientific work. Contact with the Islamic world in Sicily and Spain allowed Europeans access to preserved copies of Greek and Roman works along with the works of Islamic philosophers. Translations and commentaries of Aristotle by the Islamic scholar Averroës were influential in much of Europe. The published works of Marco Polo along with the Crusades helped spark interest in geography. Most importantly, the development of the printing press in the 1450s allowed for new ideas to be rapidly copied to multiple people.
The Middle Ages: Eastern World
See Also: Islamic science
In the Middle East, Greek philosophy was able to find some short-lived support by the newly created Arab Caliphate (Empire). With the spread of Islam in the 7th and 8th centuries, a period of Islamic scholarship lasted until the 14th century. This scholarship was aided by several factors. The use of a single language, Arabic, allowed communication without need of a translator. Access to Greek and Roman texts from the Byzantine Empire along with Indian sources of learning provided Islamic scholars a knowledge base to build upon. In addition, there was the Hajj. This annual pilgrimage to Mecca facilitated scholarly collaboration by bringing together people and new ideas from all over the Islamic world.
In Islamic versions of early scientific method, ethics played an important role. During this period the concepts of citation and peer review were developed. Previous work in medicine, astronomy and mathematics led to the development of alchemy. In mathematics, the Islamic scholar Muhammad ibn Musa al-Khwarizmi gave his name to what is now called an algorithm; the word algebra is derived from al-jabr, the beginning of the title of one of his publications. Al-Batani (850-929) contributed to astronomy and mathematics and Al-Razi to chemistry. The fruits of these contributions can be seen in Damascus steel (wootz steel), and the Baghdad Battery. Arab alchemy inspired Roger Bacon, and later Isaac Newton, too. In astronomy, Al-Batani improved the measurements of Hipparchus, preserved in the translation of the Greek Hč Megalč Syntaxis (The great treatise) translated as Almagest. Al-Batani also improved the precision of the measurement of the precession of the earth's axis.
The Scientific Revolution
Main article: Scientific Revolution
Modern science in Europe began in a period of great upheaval. The Protestant Reformation, the discovery of the Americas by Christopher Columbus, the Fall of Constantinople, the Spanish Inquisition, but also the re-discovery of Aristotle in the twelfth and thirteenth centuries presaged large social and political changes. Thus, a suitable environment was created in which it became possible to question scientific doctrine, in much the same way that Martin Luther and John Calvin questioned religious doctrine. The works of Ptolemy (Astronomy), Galen (Medicine), and Aristotle (Physics) were found to not always match everyday observations. For example, an arrow flying through the air after leaving a bow contradicts with Aristotle's assertion that the natural state of all objects is at rest. Also, work by Vesalius on human cadavers also found problems with the Galenian anatomy.
The willingness to question previously held truths and search for new answers resulted in a period of major scientific advancements, now known as the Scientific Revolution. The Scientific Revolution is held by most historians (e.g., Howard Margolis) to have begun in 1543, when there was brought to the Polish astronomer Nicolaus Copernicus the first printed copy of the book De Revolutionibus. The thesis of this book is that the Earth moves around the Sun. The period culminated with the publication of the Philosophiae Naturalis Principia Mathematica in 1687 by Isaac Newton.
Other significant scientific advances were made during this time by Galileo Galilei, Christiaan Huygens, Johannes Kepler, and Blaise Pascal. In philosophy, major contributions were made by Francis Bacon, Sir Thomas Browne, René Descartes, and Thomas Hobbes. The basics of scientific method were also developed: the new way of thinking emphasized experimentation and reason over traditional considerations.
The Scientific Revolution established scientific thinking as the preeminent model for understanding the natural world. During the 19th century, the practice of science became professionalized and institutionalized in ways which would continue through the 20th century, as the role of scientific knowledge grew and became incorporated with many aspects of the functioning of nation-states.
Main article: History of physics
The scientific revolution, beginning about year 1600, is a convenient boundary between ancient thought and classical physics. In the 16th century Nicholas Copernicus revived the heliocentric model of the solar system devised by Aristarchus . This was followed by the first known model of planetary motion given by Kepler in the early 17th century, where he proposed that the planets follow not circular orbits, but elliptical orbits with the Sun at one focus of the ellipse. Also in the early 17th century, Galileo pioneered the use of experiment to validate physical theories, which is the key idea in the scientific method.
In 1687, Isaac Newton published the Principia Mathematica, detailing two comprehensive and successful physical theories: Newton's laws of motion, from which arise classical mechanics; and Newton's Law of Gravitation, which describes the fundamental force of gravity. The behavior of electricity and magnetism was studied by Faraday, Ohm, and others during the early 19th century and led to the unification of the two phenomena into a single theory of electromagnetism, by Maxwell in 1855 which is described by Maxwell's equations.
The beginning of the 20th century brought the start of a revolution in physics. The long-held theories of Newton were shown not to be correct in all circumstances. Beginning in 1900, Planck, Einstein, Bohr, and others developed quantum theories to explain various anomalous experimental results by introducing discrete energy levels. Not only did quantum mechanics show that the laws of motion didn't hold on small scales, but even more disturbingly, the thoery of general relativity proposed by Einstein in 1915, showed that the fixed background of spacetime, on which both Newtonian mechanics and special relativity depended, could not exist. In 1925, Heisenberg and Schrödinger formulated quantum mechanics, which explained the preceding quantum theories. The observation by Edwin Hubble, in 1929 that the speed at which galaxies recede positively correlates with their distance, led to the understanding that the universe is expanding and the formulation of the Big Bang theory by George Gamow.
Important developments took place during World War II, which led to the practical application of radar and the development and use of the atomic bomb. Though the process had begun with the invention of the cyclotron by Ernest O. Lawrence in the 1930s, physics in the postwar period entered into a phase of what historians have called "Big Science", requiring massive machines, budgets, and laboratories in order to test their theories and move into new frontiers. The primary patron of physics became state governments, who recognized that the support of "basic" research could often lead to technologies useful to both military and industrial applications. Currently, general relativity and quantum mechanics are inconsistent with each other, and efforts are underway to unify the two.
Main article: History of chemistry
The history of chemistry may be said to begin with the distinction of chemistry from alchemy by Robert Boyle in his work The Skeptical Chymist (1661), but is often more strictly dated to Antoine Lavoisier's discovery of oxygen and the law of conservation of mass, and thereby to his refutation of the phlogiston theory of combustion in 1783. Proof that all matter is made of atoms, which are the smallest indestructible part of matter, was provided by John Dalton in 1803. He also formulated the law of mass relationships. In 1869, Dmitry Mendeleyev composed his periodic table of elements on the basis of Dalton's discoveries.
The Synthesis of urea by Friedrich Wöhler, opened a new research field in chemistry, and by the end of the 19th century, scientists were able to synthesize hundreds of organic compounds. The later part of the nineteenth century saw the exploitation of the petrochemicals of the earth, after the exhaustion of the oil supply from whaling in the previous centuries. Systematic production of refined materials provided a ready supply of products which not only provided energy, but also synthetic materials for clothing, medicine, and everyday disposable resources, by the twentieth century.
By the twentieth century, the integration of physics and chemistry was complete, with chemical properties explained as the result of the electronic structure of the atom; Linus Pauling's book on The Nature of the Chemical Bond used the principles of quantum mechanics to deduce bond angles in ever-more complicated molecules, culiminating in the physical modelling of the DNA molecule, in essence, the secret of life, in the words of Francis Crick. In the same year, the Miller-Urey experiment demonstrated that basic constituents of DNA, simple amino acids, could themselves be built up from simpler molecules in a simulation of primordial processes on Earth.
Main article: Geology (history)
Chinese polymath Shen Kua (1031 - 1095) formulated a hypothesis for the process of land formation: based on his observation of fossil shells in a geological stratum in a mountain hundreds of miles from the ocean, he inferred that the land was formed by erosion of the mountains and by deposition of silt.
The work on rocks Peri lithōn by Theophrastus, remained authoritative for millennia: its interpretation of fossils was not overturned until after the Scientific Revolution. By the 1700s Jean-Etienne Guettard and Nicolas Desmarest hiked central France and recorded their observations on geological maps; Guettard recorded the first observation of the volcanic origins of this part of France. James Hutton recorded his Theory of the Earth in the 1788 Transactions of the Royal Society of Edinburgh, later called uniformitarianism.
In 1811 Georges Cuvier and Alexandre Brongniart published their explanation of the antiquity of the Earth, inspired by Cuvier's discovery of fossil elephant bones in Paris. They formulated the principle of stratigraphic succession of the layers of the earth. They were independently anticipated by William Smith's stratigraphic studies on England and Scotland. By 1827 Charles Lyell's Principles of Geology reiterated Hutton's uniformitarianism, which influenced the thought of Charles Darwin.
The most significant advance in 20th century geology has been the development of the theory of plate tectonics in the 1960s. Plate tectonic theory arose out of two separate geological observations: seafloor spreading and continental drift. The theory revolutionized the Earth sciences.
Main article: History of astronomy
Advances in astronomy and in optical systems in the 19th century resulted in the first observation of an asteroid (Ceres) in 1801, and the discovery of Neptune in 1846. In the 1840s, the first galaxies outside our solar system were observed by (William Parsons).
George Gamow, Ralph Alpher, and Robert Herman had calculated that there should be evidence for a Big Bang in the background temperature of the universe. In 1964, Arno Penzias and Robert Wilson2 discovered a 3 Kelvin background hiss in their Bell Labs radiotelescope, which was evidence for this hypothesis, and formed the basis for a number of results that helped determine the age of the universe.
Supernova SN1987A was observed by astronomers on Earth both visually, and in a triumph for neutrino astronomy, by the solar neutrino detectors at Kamiokande. But the solar neutrino flux was a fraction of its theoretically-expected value. This discrepancy forced a change in some values in the standard model for particle physics.
Biology and medicine
Hungarian physician Ignác Fülöp Semmelweis in 1847 dramatically reduced the occurrency of puerperal fever by the simple experiment of requiring physicians to wash their hands before attending to women in childbirth. His discovery predated the germ theory of disease. However, his discoveries were not appreciated by his contemporaries and came into use only with discoveries of British surgeon Joseph Lister, who in 1865 proved the principles of antisepsis. His work is based on the very important discoveries made by French biologist Louis Pasteur. He was able to link some microorganisms with disease. This brought a revolution in medicine. He also devised one of the most important methods in preventive medicine, when in 1880 he produced the vaccine against rabies. Pasteur also invented the process of pasteurization to help prevent the spread of disease through milk and other foods.
Among the most prominent and far-reaching theories in all of science was the theory of evolution by natural selection put forth by the British naturalist Charles Darwin in his On the Origin of Species in 1859. Darwin's theory proposed that all differences in animals were formed by natural processes over long periods of time, and that even humans were simply evolved organisms. Implications of evolution on fields outside of pure science have led to both opposition and support from different parts of society, and profoundly influenced the popular understanding of "man's place in the universe".
In the early 20th century, the study of heredity became a major investigation after the rediscovery in 1900 of the laws of inheritance developed by the Austrian monk Gregor Mendel in 1866. Mendel's laws provided the beginnings of the study of genetics, which became a major field of research for both scientific and industrial research. By 1953 James Watson and Francis Crick clarified the basic structure of DNA, the genetic material for expressing life in all its forms3. In the late 20th century, the possibilities of genetic engineering became practical for the first time, and a massive international effort began in 1990 to map out an entire human genome (the Human Genome Project) has been touted as potentially having large medical benefits.
Main article: History of ecology
The famous Earthrise picture, taken in 1968 by the astronauts of Apollo 8, was important in creating awareness of the finiteness of Earth, and the limits of its natural resources. The interconnection and interpendence of each component ecosystem may imply that human beings should not overexploit Earth's resources, without regard for its main ecosystems (air, water, ground, plants and animals). This change of sensitivity to ecological issues has now been well established in Western civilization. Still, industrialized deforestation has occurred in the exploitation of the forests of Southeast Asia and the Amazon rainforest. It may be hypothesized that other vital and free goods (such as air) will, one day, be subject to price.
Successful use of the scientific method in the physical sciences led to the same methodology being adapted to better understand the many fields of human endeavor. From this effort the social sciences have been developed.
Main article: History of political science
One of the basic requirements for a scientific community is the existence and approval of a political sponsor; in England, the Royal Society operates under the aegis of the monarchy; in the US, the National Academy of Sciences was founded by Act of Congress; etc. Otherwise, when the basic elements of knowledge were being formulated, the political rulers of the respective communities could choose to arbitrarily either support or disallow the nascent scientific communities. For example, Alhazen had to feign madness to avoid execution. The polymath Shen Kuo lost political support, and could not continue his studies until he came up with discoveries that showed his worth to the political rulers. The admiral Zheng He could not continue his voyages of exploration after the emperors withdrew their support. Another famous example was the suppression of the work of Galileo, and before him, Giordano Bruno, burned at the stake, for his statements on cosmology; by the twentieth century, Galileo would be pardoned.
Main article: History of linguistics
While many cultures independently developed understandings of grammar and the nature of language, the field of linguistics did not emerge as an independent field of study until the late 18th Century. A proposal by Sir William Jones that Sanskrit, Persian, Greek, Latin, Gothic, and Celtic languages all shared a common base spurred the creation of historical linguistics. After this thesis emerged, an effort to catalog all the languages of the world was made through the 19th and into the 20th Century.
The posthumous publication of Cours de linguistique générale by Ferdinand de Saussure spawned the development of descriptive linguistics. Descriptive linguistics, and the accompaning structuralism movement, caused linguistics to focus on how a language changes over time instead of just looking at the differences between various languages. Noam Chomsky further diversified linguistics in the 1950s with the development of generative linguistics. This effort was based upon a mathematical model of language that allowed for the description and prediction of valid semantics. Additional specialties such as sociolinguistics, cognitive linguistics, and computational linguistics grew from collaboration between linguistics and other disciplines.
Main article: History of economic thought
The basis for classical economics was developed by Adam Smith in 1776 in his An Inquiry into the Nature and Causes of the Wealth of Nations. Smith criticized mercantilism, advocating a system of free trade with division of labour. He postulated an "Invisible Hand" that large economic systems could be self-regulating through a process of enlightened self-interest. A different type of economics, developed by Karl Marx (so-called Marxian economics) was based on the labor theory of value and assumed the value of a good was based on the amount of labor required to produce it. Under this assumption, capitalism was based on employeers not paying the full value of workers labor to create a profit. An early response to Marxian economics was made by the Austrian school. Under this school of thought, the driving force of economic development is entrepreneurship. This replaces the labor theory of value by a system of supply and demand.
From the 1920s, John Maynard Keynes prompted a division between microeconomics and macroeconomics. Under Keynesian economics macroeconomic trends can overwhelm economic choices made by individual. Governments should promote aggregate demand for goods as a means to encourage economic expansion.
Following World War II, Milton Friedman created the concept of monetarism. Friedman focused on using the supply and demand of money as a method of controlling economic activity. This work was later adapted in the 1970s into supply-side economics which advocates reducing taxes as a means to increase the amount of money available for economic expansion.
Other modern schools of economic thought are New Classical economics and New Keynesian economics. New Classical economics, developed in the 1970s, emphasises solid microeconomics as the basis for macroeconomic growth. New Keynesian economics was created partially in response to New Classical economics, and deals with how innefficiencies in the market create a need for control by a central bank or government.
Main article: History of psychology
The end of the 19th century marks the start of psychology as a scientific enterprise. The year 1879 is commonly seen as the start of psychology as an independent field of study, because in that year Wilhelm Wundt founded the first laboratory dedicated exclusively to psychological research (in Leipzig). Other important early contributors to the field include Hermann Ebbinghaus (a pioneer in studies on memory), Ivan Pavlov (who discovered the learning process of classical conditioning), and Sigmund Freud. Freud's influence has been enormous, though more as cultural icon than a force in (scientific) psychology. Freud's basic theories postulated the existence in humans of various unconscious and instinctive "drives", and that the "self" existed as a perpetual battle between the desires and demands of the internal id, ego, and superego.
The 20th century saw a rejection of Freud's theories as being too unscientific, and a reaction against Edward Titchener's abstract approach to the mind. This led to the formulation of behaviorism by John B. Watson, which was popularized by B.F. Skinner. Behaviorism proposed epistemologically limiting psychological study to overt behavior, since that could be quantified and easily measured. Scientific knowledge of the "mind" was considered too metaphysical, hence impossible to achieve. The final decades of the 20th century have seen the rise of a new interdisciplinary approach to studying human psychology, known collectively as cognitive science. Cognitive science again considers the "mind" as a subject for investigation, using the tools of evolutionary psychology, linguistics, computer science, philosophy, and neurobiology. This new form of investigation has proposed that a wide understanding of the human mind is possible, and that such an understanding may be applied to other researcg domains, such as artificial intelligence.
Main article: History of sociology
Sociology as a scientific discipline emerged in the early 19th century as an academic response to the challenge of modernity: as the world is becoming smaller and more integrated, people's experience of the world is increasingly atomized and dispersed. Sociologists try to understand what holds social groups together, and to develop an "antidote" to social disintegration.
Main article: History of anthropology
Anthropology can best be understood as an outgrowth of the Age of Enlightenment. It was during this period that Europeans attempted systematically to study human behavior. Traditions of jurisprudence, history, philology and sociology developed during this time and informed the development of the social sciences of which anthropology was a part. At the same time, the romantic reaction to the Enlightenment produced thinkers such as Johann Gottfried Herder and later Wilhelm Dilthey whose work formed the basis for the culture concept which is central to the discipline. Traditionally, much of the history of the subject was based on colonial encounters between Europe and the rest of the world, and much of 18th and 19th century anthropology is now classed as forms of scientific racism. In the mid-20th century, much of the methodologies of earlier anthropological and ethnographical study were reevaluated with an eye towards research ethics, while at the same time the scope of investigation has broadened far beyond the traditional study of "primitive cultures" (scientific practice itself is often an arena of anthropological study).
During the 20th century a number of new, interdisciplinary scientific fields have emerged. Communication studies combines the studies of animal communication, information theory, marketing, public relations, telecommunications and other forms of communications.
Built mostly upon a foundation of theoretical linguistics, discrete mathematics, and electrical engineering, computer science studies the nature and limits of computation. Fields of specialization include computability, computational complexity, database design, computer networking, artificial intelligence, and the design of computer hardware. Computer science provides much of the theoretical basis for software engineering.
Materials science is an interdisciplinary field that combines chemistry, physics, and several engineering disciplines. The field studies metals, ceramics, plastics, semiconductors, and composite materials. Its historical roots are in the disciplines of metallurgy, minerology, and crystallography.
- History of science and technology (academic field of study)
- Philosophy and Logic
- Epistemology (Branch of philosophy concerning the nature, origin and scope of knowledge)
- History of history
- Indian science
- Obsolete scientific theory
- Science studies
- Timelines of Science
- List of famous experiments
- List of scientists
- List of Nobel laureates
- List of years in science
==Notes==Alpher, Herman, and Gamow. Nature 162,774 (1948).
- Thomas S. Kuhn (1996). The Structure of Scientific Revolutions (3rd ed.). University of Chicago Press. ISBN 0226458075
- Howard Margolis (2002). It Started with Copernicus. New York: McGraw-Hill. ISBN 0-07-138507-X
- Joseph Needham. Science and Civilisation in China. Multiple volumes (1954-2004).
- Bertrand Russell (1945). A History of Western Philosophy: And Its Connection with Political and Social Circumstances from the Earliest Times to the Present Day. New York: Simon and Schuster.
- Leonard C. Bruno (1989), The Landmarks of Science. ISBN 0-8160-2137-6
- John L. Heilbron, ed., The Oxford companion to the history of modern science (New York: Oxford University Press, 2003).
- A History of Science, Vols 1-4, online text
- MIT STS.002 - Toward the Scientific Revolution. From MIT OpenCourseWare, class materials for the history of science up to and including Isaac Newton.
- MIT STS.042 - Einstein, Oppenheimer, Feynman: Physics in the 20th Century. Class materials for the history of physics in the 20th century.
- Contributions of 20th century Women to Physics ("CWP")
- The official site of the Nobel Foundation. Features biographies and info on Nobel laureates
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