Incubator is a device used to grow and maintain microbiological cultures or cell cultures. The incubator maintains optimal temperature and other conditions such as the CO and oxygen content of the atmosphere inside. Incubators are essential for a lot of experimental work in cell biology and molecular biology and are used to culture both bacterial as well as eukaryotic cells. Louis Pasteur used the small opening underneath his staircase as an incubator. Incubators are used in the poultry industry to act as a substitute for hens; this results in higher hatch rates due to the ability to control both temperature and humidity. Various brands of incubators are commercially available to breeders; the simplest incubators are insulated boxes with an adjustable heater going up to 60 to 65 °C, though some can go higher. The most used temperature both for bacteria such as the used E. coli as well as for mammalian cells is 37 °C, as these organisms grow well under such conditions. For other organisms used in biological experiments, such as the budding yeast Saccharomyces cerevisiae, a growth temperature of 30 °C is optimal.
More elaborate incubators can include the ability to lower the temperature, or the ability to control humidity or CO2 levels. This is important in the cultivation of mammalian cells, where the relative humidity is >80% to prevent evaporation and a acidic pH is achieved by maintaining a CO2 level of 5%. From aiding in hatching chicken eggs to enabling scientists to understand and develop vaccines for deadly viruses, the laboratory incubator has seen numerous applications over the thousands of years it has been in use; the incubator has provided a foundation for medical advances and experimental work in cellular and molecular biology. An incubator is made up of a chamber with a regulated temperature; some incubators regulate humidity, gas composition, or ventilation within that chamber. While many technological advances have occurred since the primitive incubators first used in ancient Egypt and China, the main purpose of the incubator has remained unchanged: to create a stable, controlled environment conducive to research and cultivation.
The earliest incubators were found thousands of years ago in ancient Egypt and China, where they were used to keep chicken eggs warm.. Use of incubators revolutionized food production, as it allowed chicks to hatch from eggs without requiring that a hen sit on them, thus freeing the hens to lay more eggs in a shorter period of time. Both early Egyptian and Chinese incubators were large rooms that were heated by fires, where attendants turned the eggs at regular intervals to ensure heat distribution.. The incubator received an update in the 16th century when Jean Baptiste Porta drew on ancient Egyptian design to create a more modern egg incubator. While he had to discontinue his work due to the Spanish Inquisition, Rene-Antoine Ferchault de Reaumur took up the challenge in the middle of the 17th century. Reaumur warmed his incubator with a wood stove and monitored its temperature using the Reaumur thermometer, another of his inventions. In the 19th century, researchers began to recognize that the use of incubators could contribute to medical advancements.
They began to experiment to find the ideal environment for maintaining cell culture stocks. These early incubators were made up of bell jars that contained a single lit candle. Cultures were placed near the flame on the underside of the jar's lid, the entire jar was placed in a dry, heated oven. In the late 19th century, doctors realized another practical use for incubators: keeping premature or weak infants alive; the first infant incubator, used at a women's hospital in Paris, was heated by kerosene lamps. Fifty years Julius H. Hess, an American physician considered to be the father of neonatology, designed an electric infant incubator that resembles the infant incubators in use today; the next innovation in incubator technology came in the 1960s, when the CO2 incubator was introduced to the market. Demand came when doctors realized that they could use CO2 incubators to identify and study pathogens found in patients' bodily fluids. To do this, a sample was placed onto a sterile dish and into the incubator.
The air in the incubator was kept at 37 degrees Celsius, the same temperature as the human body, the incubator maintained the atmospheric carbon dioxide and nitrogen levels necessary to promote cell growth. At this time, incubators began to be used in genetic engineering. Scientists could create biologically essential proteins, such as insulin, with the use of incubators. Genetic modification could now take place on a molecular level, helping to improve the nutritional content and resistance to pestilence and disease of fruits and vegetables. Incubators serve a variety of functions in a scientific lab. Incubators maintain a constant temperature, however additional features are built in. Many incubators control humidity. Shaking incubators incorporate movement to mix cultures. Gas incubators regulate the internal gas composition; some incubators have a means of circulating the air inside of them to ensure distribution of temperatures. Many incubators built for laboratory use have a redundant power source, to ensure that power outages do not disrupt experiments.
Incubators are made in a variety of sizes, from tabletop models, to warm rooms, which serve as incubators for large numbers of samples. Egyptian egg oven
For other forms of development, see Development. International development or global development is a broad concept denoting the idea that societies and countries have differing levels of'development' on an international scale, it is the basis for international classifications such as developed country, developing country and least developed country, for a field of practice and research that in various ways engages with international development processes. There are, many schools of thought and conventions regarding which are the exact features constituting the'development' of a country. Development has been synonymous with economic development. More writers and practitioners have begun to discuss development in the more holistic and multi-disciplinary sense of human development. Other related concepts are, for instance, quality of life or subjective well-being.'International development' is different from the simple concept of'development'. Whereas the latter, at its most basic, denotes the idea of change through time, international development has come to refer to a distinct field of practice and research.
It remains related to the set of institutions - the Bretton Woods Institutions - that arose after the Second World War with a focus on economic growth, alleviating poverty, improving living conditions in colonised countries. The international community has codified development aims in, for instance, the Millennium Development Goals and Sustainable Development Goals. Although international relations and international trade have existed for many hundreds of years, it is only in the past century that international development theory emerged as a separate body of ideas. More it has been suggested that'the theory and practice of development is inherently technocratic, remains rooted in the high modernist period of political thought that existed in the immediate aftermath of the Second World War'. Throughout the 20th century, before the concept of international development became a common word, four aspects were used to describe the idea: political and economic liberalism, the significance of "free markets" social evolution in hierarchized environment Marxist critiques of class and imperialism anti-colonial take on cultural differences and national self-determination The second half of the 20th century has been called the'era of development'.
The origins of this era have been attributed to: the need for reconstruction in the immediate aftermath of World War II. The start of the Cold War and the desire of the United States and its allies to prevent the Third World from drifting towards communism. International Development in its meaning is geared towards colonies that gained independence; the governance of the newly independent states should be constructed so that the inhabitants enjoy freedom from poverty and insecurity. It has been argued that this era was launched on January 20, 1949, when Harry S. Truman made these remarks in his inaugural address: Before this date, the United States had taken a leading role in the creation of the International Bank for Reconstruction and Development and the International Monetary Fund, both established in 1944, in the United Nations in 1945; the launch of the Marshall Plan was another important step in setting the agenda for international development, combining humanitarian goals with the creation of a political and economic bloc in Europe, allied to the U.
S. This agenda was given conceptual support during the 1950s in the form of modernization theory espoused by Walt Rostow and other American economists; the changes in the'developed' world's approach to international development were further necessitated by the gradual collapse of Western Europe's empires over the next decades. By the late 1960s, dependency theory arose analysing the evolving relationship between the West and the Third World. In the 1970s and early 1980s, the modernists at the World Bank and IMF adopted the neoliberal ideas of economists such as Milton Friedman or Béla Balassa, which were implemented in the form of structural adjustment programs, while their opponents were promoting various'bottom up' approaches, ranging from civil disobedience and conscientization to appropriate technology and Rapid Rural Appraisal. In response various parts of the UN system led a counter movement, which in the long run has proved to be successful, they were led by the International Labour Organization, influenced by Paul Streeten by UNICEF.
UNDP though headed by a conservative US republican, put forward the concept of Human Development, thanks to Mahboub ul Haq and Amartya Sen, thus changing the nature of the development dialogue to focus on human needs and capabilities. By the 1990s, there were some writers for whom development theory had reached an impasse and some academics were imagining a postdevelopment era; the Cold War had ended, capitalism had become the dominant mode of social organization, UN statistics showed that living standards around the world had improved over the past 40 years. A large portion of the world's population were still living in poverty, their governments were crippled by debt and concerns about the environmental impact of globalization were rising. In response to the impasse, the rhetoric of development is now focusing on the issue of pove
Massachusetts Institute of Technology
The Massachusetts Institute of Technology is a private research university in Cambridge, Massachusetts. Founded in 1861 in response to the increasing industrialization of the United States, MIT adopted a European polytechnic university model and stressed laboratory instruction in applied science and engineering; the Institute is a land-grant, sea-grant, space-grant university, with a campus that extends more than a mile alongside the Charles River. Its influence in the physical sciences and architecture, more in biology, linguistics and social science and art, has made it one of the most prestigious universities in the world. MIT is ranked among the world's top universities; as of March 2019, 93 Nobel laureates, 26 Turing Award winners, 8 Fields Medalists have been affiliated with MIT as alumni, faculty members, or researchers. In addition, 58 National Medal of Science recipients, 29 National Medals of Technology and Innovation recipients, 50 MacArthur Fellows, 73 Marshall Scholars, 45 Rhodes Scholars, 41 astronauts, 16 Chief Scientists of the US Air Force have been affiliated with MIT.
The school has a strong entrepreneurial culture, the aggregated annual revenues of companies founded by MIT alumni would rank as the tenth-largest economy in the world. MIT is a member of the Association of American Universities. In 1859, a proposal was submitted to the Massachusetts General Court to use newly filled lands in Back Bay, Boston for a "Conservatory of Art and Science", but the proposal failed. A charter for the incorporation of the Massachusetts Institute of Technology, proposed by William Barton Rogers, was signed by the governor of Massachusetts on April 10, 1861. Rogers, a professor from the University of Virginia, wanted to establish an institution to address rapid scientific and technological advances, he did not wish to found a professional school, but a combination with elements of both professional and liberal education, proposing that: The true and only practicable object of a polytechnic school is, as I conceive, the teaching, not of the minute details and manipulations of the arts, which can be done only in the workshop, but the inculcation of those scientific principles which form the basis and explanation of them, along with this, a full and methodical review of all their leading processes and operations in connection with physical laws.
The Rogers Plan reflected the German research university model, emphasizing an independent faculty engaged in research, as well as instruction oriented around seminars and laboratories. Two days after MIT was chartered, the first battle of the Civil War broke out. After a long delay through the war years, MIT's first classes were held in the Mercantile Building in Boston in 1865; the new institute was founded as part of the Morrill Land-Grant Colleges Act to fund institutions "to promote the liberal and practical education of the industrial classes" and was a land-grant school. In 1863 under the same act, the Commonwealth of Massachusetts founded the Massachusetts Agricultural College, which developed as the University of Massachusetts Amherst. In 1866, the proceeds from land sales went toward new buildings in the Back Bay. MIT was informally called "Boston Tech"; the institute adopted the European polytechnic university model and emphasized laboratory instruction from an early date. Despite chronic financial problems, the institute saw growth in the last two decades of the 19th century under President Francis Amasa Walker.
Programs in electrical, chemical and sanitary engineering were introduced, new buildings were built, the size of the student body increased to more than one thousand. The curriculum drifted with less focus on theoretical science; the fledgling school still suffered from chronic financial shortages which diverted the attention of the MIT leadership. During these "Boston Tech" years, MIT faculty and alumni rebuffed Harvard University president Charles W. Eliot's repeated attempts to merge MIT with Harvard College's Lawrence Scientific School. There would be at least six attempts to absorb MIT into Harvard. In its cramped Back Bay location, MIT could not afford to expand its overcrowded facilities, driving a desperate search for a new campus and funding; the MIT Corporation approved a formal agreement to merge with Harvard, over the vehement objections of MIT faculty and alumni. However, a 1917 decision by the Massachusetts Supreme Judicial Court put an end to the merger scheme. In 1916, the MIT administration and the MIT charter crossed the Charles River on the ceremonial barge Bucentaur built for the occasion, to signify MIT's move to a spacious new campus consisting of filled land on a mile-long tract along the Cambridge side of the Charles River.
The neoclassical "New Technology" campus was designed by William W. Bosworth and had been funded by anonymous donations from a mysterious "Mr. Smith", starting in 1912. In January 1920, the donor was revealed to be the industrialist George Eastman of Rochester, New York, who had invented methods of film production and processing, founded Eastman Kodak. Between 1912 and 1920, Eastman donated $20 million in cash and Kodak stock to MIT. In the 1930s, President Karl Taylor Compton and Vice-President Vannevar Bush emphasized the importance of pure sciences like physics and chemistry and reduced the vocational practice required in shops and drafting studios; the Compton reforms "renewed confidence in the ability of the Institute to develop leadership in science as well as in engineering". Unlike Ivy League schools, MIT catered more to middle-class families, depended more on tuition than on endow
Microbiology is the study of microorganisms, those being unicellular, multicellular, or acellular. Microbiology encompasses numerous sub-disciplines including virology, parasitology and bacteriology. Eukaryotic microorganisms possess membrane-bound cell organelles and include fungi and protists, whereas prokaryotic organisms—all of which are microorganisms—are conventionally classified as lacking membrane-bound organelles and include Bacteria and Archaea. Microbiologists traditionally relied on culture and microscopy. However, less than 1% of the microorganisms present in common environments can be cultured in isolation using current means. Microbiologists rely on molecular biology tools such as DNA sequence based identification, for example 16s rRNA gene sequence used for bacteria identification. Viruses have been variably classified as organisms, as they have been considered either as simple microorganisms or complex molecules. Prions, never considered as microorganisms, have been investigated by virologists, however, as the clinical effects traced to them were presumed due to chronic viral infections, virologists took search—discovering "infectious proteins".
The existence of microorganisms was predicted many centuries before they were first observed, for example by the Jains in India and by Marcus Terentius Varro in ancient Rome. The first recorded microscope observation was of the fruiting bodies of moulds, by Robert Hooke in 1666, but the Jesuit priest Athanasius Kircher was the first to see microbes, which he mentioned observing in milk and putrid material in 1658. Antonie van Leeuwenhoek is considered a father of microbiology as he observed and experimented with microscopic organisms in 1676, using simple microscopes of his own design. Scientific microbiology developed in the 19th century through the work of Louis Pasteur and in medical microbiology Robert Koch; the existence of microorganisms was hypothesized for many centuries before their actual discovery. The existence of unseen microbiological life was postulated by Jainism, based on Mahavira’s teachings as early as 6th century BCE. Paul Dundas notes that Mahavira asserted the existence of unseen microbiological creatures living in earth, water and fire.
Jain scriptures describe nigodas which are sub-microscopic creatures living in large clusters and having a short life, said to pervade every part of the universe in tissues of plants and flesh of animals. The Roman Marcus Terentius Varro made references to microbes when he warned against locating a homestead in the vicinity of swamps "because there are bred certain minute creatures which cannot be seen by the eyes, which float in the air and enter the body through the mouth and nose and thereby cause serious diseases."In the golden age of Islamic civilization, Iranian scientists hypothesized the existence of microorganisms, such as Avicenna in his book The Canon of Medicine, Ibn Zuhr who discovered scabies mites, Al-Razi who gave the earliest known description of smallpox in his book The Virtuous Life. In 1546, Girolamo Fracastoro proposed that epidemic diseases were caused by transferable seedlike entities that could transmit infection by direct or indirect contact, or vehicle transmission.
In 1676, Antonie van Leeuwenhoek, who lived most of his life in Delft, observed bacteria and other microorganisms using a single-lens microscope of his own design. He is considered a father of microbiology as he pioneered the use of simple single-lensed microscopes of his own design. While Van Leeuwenhoek is cited as the first to observe microbes, Robert Hooke made his first recorded microscopic observation, of the fruiting bodies of moulds, in 1665, it has, been suggested that a Jesuit priest called Athanasius Kircher was the first to observe microorganisms. Kircher was among the first to design magic lanterns for projection purposes, so he must have been well acquainted with the properties of lenses, he wrote "Concerning the wonderful structure of things in nature, investigated by Microscope" in 1646, stating "who would believe that vinegar and milk abound with an innumerable multitude of worms." He noted that putrid material is full of innumerable creeping animalcules. He published his Scrutinium Pestis in 1658, stating that the disease was caused by microbes, though what he saw was most red or white blood cells rather than the plague agent itself.
The field of bacteriology was founded in the 19th century by Ferdinand Cohn, a botanist whose studies on algae and photosynthetic bacteria led him to describe several bacteria including Bacillus and Beggiatoa. Cohn was the first to formulate a scheme for the taxonomic classification of bacteria, to discover endospores. Louis Pasteur and Robert Koch were contemporaries of Cohn, are considered to be the father of microbiology and medical microbiology, respectively. Pasteur is most famous for his series of experiments designed to disprove the widely held theory of spontaneous generation, thereby solidifying microbiology's identity as a biological science. One of his students, Adrien Certes, is considered the founder of marine microbiology. Pasteur designed methods for food preservation and vaccines against several diseases such as anthrax, fowl cholera and rabies. Koch is best known for his contributions to the germ theory of disease, proving that specific diseases were caused by specific pathogenic microorganisms.
He developed a series of criteria. Koch was one of the first scientists to focus on the i
A microorganism, or microbe, is a microscopic organism, which may exist in its single-celled form or in a colony of cells. The possible existence of unseen microbial life was suspected from ancient times, such as in Jain scriptures from 6th century BC India and the 1st century BC book On Agriculture by Marcus Terentius Varro. Microbiology, the scientific study of microorganisms, began with their observation under the microscope in the 1670s by Antonie van Leeuwenhoek. In the 1850s, Louis Pasteur found that microorganisms caused food spoilage, debunking the theory of spontaneous generation. In the 1880s, Robert Koch discovered that microorganisms caused the diseases tuberculosis and anthrax. Microorganisms include all unicellular organisms and so are diverse. Of the three domains of life identified by Carl Woese, all of the Archaea and Bacteria are microorganisms; these were grouped together in the two domain system as Prokaryotes, the other being the eukaryotes. The third domain Eukaryota includes all multicellular organisms and many unicellular protists and protozoans.
Some protists are related to some to green plants. Many of the multicellular organisms are microscopic, namely micro-animals, some fungi and some algae, but these are not discussed here, they live in every habitat from the poles to the equator, geysers and the deep sea. Some are adapted to extremes such as hot or cold conditions, others to high pressure and a few such as Deinococcus radiodurans to high radiation environments. Microorganisms make up the microbiota found in and on all multicellular organisms. A December 2017 report stated that 3.45-billion-year-old Australian rocks once contained microorganisms, the earliest direct evidence of life on Earth. Microbes are important in human culture and health in many ways, serving to ferment foods, treat sewage, produce fuel and other bioactive compounds, they are essential tools in biology as model organisms and have been put to use in biological warfare and bioterrorism. They are a vital component of fertile soils. In the human body microorganisms make up the human microbiota including the essential gut flora.
They are the pathogens responsible for many infectious diseases and as such are the target of hygiene measures. The possible existence of microorganisms was discussed for many centuries before their discovery in the 17th century. By the fifth century BC, the Jains of present-day India postulated the existence of tiny organisms called nigodas; these nigodas are said to be born in clusters. According to the Jain leader Mahavira, the humans destroy these nigodas on a massive scale, when they eat, breathe and move. Many modern Jains assert that Mahavira's teachings presage the existence of microorganisms as discovered by modern science; the earliest known idea to indicate the possibility of diseases spreading by yet unseen organisms was that of the Roman scholar Marcus Terentius Varro in a 1st-century BC book titled On Agriculture in which he called the unseen creatures animalcules, warns against locating a homestead near a swamp: … and because there are bred certain minute creatures that cannot be seen by the eyes, which float in the air and enter the body through the mouth and nose and they cause serious diseases.
In The Canon of Medicine, Avicenna suggested that tuberculosis and other diseases might be contagious. Akshamsaddin mentioned the microbe in his work Maddat ul-Hayat about two centuries prior to Antonie Van Leeuwenhoek's discovery through experimentation: It is incorrect to assume that diseases appear one by one in humans. Disease infects by spreading from one person to another; this infection occurs through seeds that are so small they are alive. In 1546, Girolamo Fracastoro proposed that epidemic diseases were caused by transferable seedlike entities that could transmit infection by direct or indirect contact, or without contact over long distances. Antonie Van Leeuwenhoek is considered to be the father of microbiology, he was the first in 1673 to discover, describe and conduct scientific experiments with microoorganisms, using simple single-lensed microscopes of his own design. Robert Hooke, a contemporary of Leeuwenhoek used microscopy to observe microbial life in the form of the fruiting bodies of moulds.
In his 1665 book Micrographia, he made drawings of studies, he coined the term cell. Louis Pasteur exposed boiled broths to the air, in vessels that contained a filter to prevent particles from passing through to the growth medium, in vessels without a filter, but with air allowed in via a curved tube so dust particles would settle and not come in contact with the broth. By boiling the broth beforehand, Pasteur ensured that no microorganisms survived within the broths at the beginning of his experiment. Nothing grew in the broths in the course of Pasteur's experiment; this meant that the living organisms that grew in such broths came from outside, as spores on dust, rather than spontaneously generated within the broth. Thus, Pasteur supported the germ theory of disease. In 1876, Robert Koch established, he found that the blood of cattle which were infected with anthrax always had large numbers of Bacillus anthracis. Koch found that he could transmit anthrax from one animal to another by taking a small sample of blood from the infected animal and injecting it into a healthy one, this caused the healthy animal to become sick.
He found that he could grow the bacteria in a nutrient broth inject it into a heal