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data/en.wikipedia.org/wiki/Astronomy_education-0.md
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title: "Astronomy education"
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source: "https://en.wikipedia.org/wiki/Astronomy_education"
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category: "reference"
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tags: "science, encyclopedia"
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Astronomy education or astronomy education research (AER) refers both to the methods currently used to teach the science of astronomy and to an area of discipline-based education research that seeks to improve those methods. Specifically, AER includes systematic techniques honed in science and physics education to understand what and how students learn about astronomy and determine how teachers can create more effective learning environments.
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Education is important to astronomy as it impacts both the recruitment of future astronomers and the appreciation of astronomy by citizens and politicians who support astronomical research. Astronomy has been taught throughout much of recorded human history, and has practical application in timekeeping and navigation. Teaching astronomy contributes to an understanding of physics and the origin of the world around us, a shared cultural background, and a sense of wonder and exploration. It includes education of the general public through planetariums, books, and instructive presentations, plus programs and tools for amateur astronomy, and University-level degree programs for professional astronomers. Astronomy organizations provide educational functions and societies in about 100 nation states around the world.
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In schools, particularly at the collegiate level, astronomy is aligned with physics and the two are often combined to form a Department of Physics and Astronomy. Some parts of astronomy education overlap with physics education, however, astronomy education has its own arenas, practitioners, journals, and research. This can be demonstrated in the identified 20-year lag between the emergence of AER and physics education research. The body of research in this field are available through electronic sources such as the Searchable Annotated Bibliography of Education Research (SABER) and the American Astronomical Society's database of the contents of their journal "Astronomy Education Review" (see link below).
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The National Aeronautics and Space Administration (NASA) has also created a Center for Astronomy Education, a program designed to support the professional development of astronomy instructors through the NASA JPL Exoplanet Exploration Public Engagement Program and the Spitzer Education and Outreach Program.
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== See also ==
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European Association for Astronomy Education
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Universe Awareness
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Astronomical Society of the Pacific
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== References ==
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== External links ==
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Homepage of IAU Commission 46 on Astronomy Education
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Astronomy Education Resources at the Astronomical Society of the Pacific
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Resource Guides for Astronomy Education
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Subject Index to the journal "Astronomy Education Review"
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iSTAR international Studies of Astronomy education Research Database of Articles, Theses, & Dissertations
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data/en.wikipedia.org/wiki/Balsa_wood_bridge-0.md
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data/en.wikipedia.org/wiki/Balsa_wood_bridge-0.md
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title: "Balsa wood bridge"
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source: "https://en.wikipedia.org/wiki/Balsa_wood_bridge"
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category: "reference"
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tags: "science, encyclopedia"
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The building of balsa-wood bridges is often used as an educational technology. It may be accompanied by a larger project involving varying areas of study.
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Typically classes which would include a balsa wood bridge cover the subject areas of physics, engineering, static equilibrium, or building trades, although it may be done independently of any of these subjects. Building a balsa wood bridge can be done after completing a section or unit covering a related topic or the process of design and building can be used to guide students to a better understanding of the desired subject area.
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== Requirements ==
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Although there is great variety between different balsa wood bridge projects, students are in general trying to build a bridge that can withstand the greatest weight before it fails. Other restrictions are often applied, but these vary widely from one contest to another.
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Sample requirements include:
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restricting the maximum mass of the bridge
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requiring a minimum span
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requiring a minimum height of the roadway
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restricting the physical dimensions of the bridge
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restricting the size of individual pieces of balsa wood
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limiting the amount of glue or balsa wood that can be used
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requiring a driveable roadway that allows passage of a vehicle of specified size
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restricting the way pieces are placed on the bridge (for example no parallel joining pieces)
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== Testing ==
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Bridges are usually tested by applying a downward force on the bridge. How and where the force is applied varies from one contest to the next. There are two common methods of applying the test force to the bridge:
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By hanging a container (such as a trash can) from the bridge and loading known weights into the container until the bridge breaks. The tester could also slowly add water or sand to the container until the bridge breaks and then weigh the container, providing a more accurate way to find the breaking force.
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By using a mechanical or pneumatic testing device that pushes down on the bridge with increasing force until the bridge breaks. If such a testing device is used it is often equipped with a method of automatically gathering force data, such as a pressure sensor or load cell connected to a computer. This approach is more accurate at measuring bridges that have secondary structure that proves to be stronger than the primary structure. This method is also less damaging to the bridge, whose structure usually remains intact since the load is automatically relieved at failure.
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Of the two, the hanging container method provides by far the greater dramatic effect. Testing with a pneumatic press or ram is often complete in matter of seconds. Exceptionally strong bridges may take up to thirty minutes to test as weight (a combination of steel weights and sand is often used) is added to the suspended container.
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== Scoring and Grading ==
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=== Scoring ===
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There are two chief ways that balsa wood bridge competitions may be scored. One way is simply by measuring how much weight each bridge can support. The second way is by structural efficiency, often expressed as a strength to weight ratio. The weight-only method is most effective where competitors are all building from a specified set of materials and are expected to use all the available materials. The strength-to-weight method is better when competitors are expected to use their materials as efficiently as possible.
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=== Competitive Grading ===
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Competitive grading compares how well each bridge does against bridges built by other participants to determine a grade. The top scoring bridge is assigned a maximum numeric grade (say, 100%) while the lowest scoring bridge that still meets all basic specifications is assigned a minimum grade (say, 70%).
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The method guarantee that some scores will be high even if the overall quality of bridges is low. Conversely, it also guarantees that some scores will be low, even in situations where all bridges are of high quality.
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=== Standards-Based Grading ===
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Standards-based grading sets certain standards that need to be met in order to earn a certain grade. An example of standards-based scoring would be to say that all bridges that hold 50 kilograms (110 lb) earn full credit; bridges that hold 25 kilograms (55 lb) earn half credit, and bridges that hold less than 10 kilograms (22 lb) earn no credit.
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This method allows every bridge to potentially earn full credit if the standards are met. In situations where competition is weak, this method runs the risk of having many competitors receive no credit.
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== See also ==
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Spaghetti bridge
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Bridge
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Balsa
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Trusses
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Statics
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Physics
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Civil Engineering
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Problem Based Learning
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== References ==
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Barron, B. J., Schwartz, D. L., Vye, N. J., Moore, A., Petrosino, A., Zech, L., et al. (1998). Doing with understanding: Lessons from research on problem- and project-based learning. The Journal of the Learning Sciences, 7, 271–311.
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Dods, R. F. (1997). An action research study of the effectiveness of problem-based learning in promoting the acquisition and retention of knowledge. Journal for the Education of the Gifted, 20(4), 423–437.
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Schneider, R. M., Krajcik, J., Marx, R., & Soloway, E. (2002). Performance of students in project-based science classrooms on a national measure of science achievement. Journal of Research in Science Teaching, 39(5), 410–422.
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== External links ==
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BalsaBridge.com Photos, records, tips from contest held annually since 1980 at Notre Dame Regional Secondary in Vancouver BC
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data/en.wikipedia.org/wiki/BioBus-0.md
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title: "BioBus"
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source: "https://en.wikipedia.org/wiki/BioBus"
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category: "reference"
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tags: "science, encyclopedia"
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date_saved: "2026-05-05T04:19:08.478115+00:00"
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Biobus is a novel concept in science education involving a bus that has been equipped as a self-contained, mobile laboratory used to educate K-12 students in biology basics. The bus may also be used for other audiences such as community organizations. Typically, a school or organization requests a visit, and the bus, staffed by scientists, arrives onsite so that it can involve students in participatory science experiments and presentations. The objective is to demonstrate to young people the fun of actual science, as opposed to textbook learning.
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The first Biobus program was created in 1999 by Georgia State University (GSU), with grant assistance from the National Science Foundation. Since its founding, the GSU Biobus has made 1,000 visits involving over 286,000 people. The concept has spread beyond Georgia, including New York City.
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== References ==
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== External links ==
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Georgia State University Biobus Archived 2008-08-28 at the Wayback Machine
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BioBus, Inc. (NYC)
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Science Edutainment
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Inspiring a new generation of nanoscientists (SPIE Professional)
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Ben Dubin-Thaler & Sarah Weisberg: The BioBus Mobile Science Lab
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data/en.wikipedia.org/wiki/Biomedical_Research_Center-0.md
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data/en.wikipedia.org/wiki/Biomedical_Research_Center-0.md
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title: "Biomedical Research Center"
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source: "https://en.wikipedia.org/wiki/Biomedical_Research_Center"
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category: "reference"
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tags: "science, encyclopedia"
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date_saved: "2026-05-05T04:19:09.757805+00:00"
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The Biomedical Research Center (BRC) is a research center at Qatar University focusing on biomedical research. BRC was founded in 2014, and partners with the Ministry of Public Health (Qatar), and Hamad Medical Corporation (HMC).
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== History ==
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The incidence of genetic disorders in Qatar is high, with the top three causes of death in the country being cancer, heart diseases, and diabetes. The government saw the creation of BRC as a strategy for proactively preventing diseases to help foster public health.
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BRC labs received the ISO/IEC - 17025 accreditation from the American Association for Laboratory Accreditation (A2LA). This research center focus on infectious diseases (virology and microbiology), metabolic disorders, and biomedical omics.
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== Research ==
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Since its establishment in 2014, the BRC has published over 530 research papers. The centre's research projects encompass a range of areas, including:
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Antibiotic profiling of antibiotic-resistant microbes in humans and animals.
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Investigating variations in cases of type 2 diabetes.
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Studying COVID-19, including the Omicron variant.
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Conducting genetic sequencing of Qatari falcons, endangered animal species, and the dugong.
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Exploring nanomedicine as a means of disease prevention.
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== Zebrafish Research Model ==
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BRC Introduced the use of zebrafish as an animal model in biomedical research and established a facility for it in 2015. The facility is used as a research unit to study many genetic diseases. The Ministry of Public Health articulated an institutional research policy (IRP) on the use of zebrafish in research, which Qatar University backed.
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== Facilities ==
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The BRC facilities include:
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Biosafety level 3 (BSL3) built by CERTEK, USA; for research on risk group 3 pathogens.
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Sequencing unit to conduct research in genomics.
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== See also ==
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Mariam Al Maadeed
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Sidra Medical and Research Center
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== References ==
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== External links ==
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Research and Graduate Studies Office at Qatar University
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Qatar University Newsroom
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Zebrafish Development
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---
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title: "Bruce Alberts Award for Excellence in Science Education"
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source: "https://en.wikipedia.org/wiki/Bruce_Alberts_Award_for_Excellence_in_Science_Education"
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category: "reference"
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---
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The Bruce Alberts Award for Excellence in Science Education is awarded annually by the American Society for Cell Biology. It is awarded to an individual who has demonstrated innovative and sustained contributions to science education, with particular emphasis on the broad local, regional, and/or national impact.
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== Awardees ==
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2020 Steven Farber
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2020 Jamie Shuda
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2019 Mary Pat Wenderoth
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2018 Erin Dolan
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2017 Kimberly Tanner
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2016 David Lopatto
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2015 Deborah Harmon Hines
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2014 Edison Fowlks
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2013 Deborah Allen
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2012 L.C. (Cam) Cameron
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2011 Peter Bruns
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2010 BioQUEST Curriculum Consortium
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2009 Manuel Berriozábal and Toby Horn
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2008 Wm. David Burns and Karen K. Oates
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2007 Patricia J. Pukkila
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2006 A. Malcolm Campbell and Sarah C.R. Elgin
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2005 Samuel Silverstein
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2004 William Wood
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2003 Nancy Hutchison
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2002 Sandra Mayrand
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2001 David Bynum
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2000 Virginia Shepherd
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1999 Eugenie Scott
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1998 Robert DeHaan
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== References ==
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---
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title: "Canadian Bioinformatics Workshops"
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source: "https://en.wikipedia.org/wiki/Canadian_Bioinformatics_Workshops"
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category: "reference"
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date_saved: "2026-05-05T04:19:13.488101+00:00"
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Canadian Bioinformatics Workshops (CBW) are a series of advanced training workshops in bioinformatics offered across Canada since 1999. The program was established in response to a growing need for bioinformatics expertise in the Canadian life sciences sector, identified in policy and workforce reports on biotechnology and computational biology in Canada. The workshops provide intensive short courses combining lectures with hands-on computational training using biological datasets and have trained researchers and students across Canada.
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== Founding and early workshops in British Columbia (1999–2007) ==
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The Canadian Bioinformatics Workshops series began offering one- and two-week short courses in bioinformatics, genomics and proteomics in 1999, in response to an identified need for a skilled bioinformatics workforce in Canada. In partnership with the Canadian Genetics Diseases Network and Human Resources Development Canada, and under the scientific direction of Director, Francis Ouellette, the CBW series was established.
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For eight years, the series offered short courses in bioinformatics, genomics and proteomics in various cities across Canada. The courses were taught by top faculty from Canada and the US, and offered small classes and hands-on instruction.
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== Expansion at the Ontario Institute for Cancer Research (2007–2018) ==
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In 2007, the Canadian Bioinformatics Workshops moved to Toronto and were hosted by the Ontario Institute for Cancer Research (OICR). The program was led by Francis Ouellette with Michelle Brazas serving as project manager. During this period the workshops were redesigned to emphasize short, intensive courses combining lectures with hands-on computational exercises using real biological datasets. The Canadian Bioinformatics Workshops began offering two-day advanced topic workshops in 2008.
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== Workshops hosted at McGill University (2018–2021) ==
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In 2018, the series was hosted by McGill University with support from the Ontario Institute for Cancer Research. As a result of the global pandemic, the format of workshops changed to virtual in 2020. In 2021, Francis Ouellette stepped down from scientific leadership of Bioinformatics.ca and CBW.
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== Return to Ontario and national expansion (2021–present) ==
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With funding support from the Canadian Institutes of Health Research, Genome Canada and Ontario Genomics, Bioinformatics.ca moved back to the Ontario Institute for Cancer Research under the leadership of Dr. Michelle Brazas (CBW Program Manager from 2007-2015) and underwent a reimagining exercise to scale the workshops across the country.
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All workshop material is licensed under a Creative Commons-Share Alike 4.0 license and is available on the CBW Git site.
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The CBW is sponsored by the Canadian Institutes of Health Research and the Ontario Institute for Cancer Research.
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== References ==
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== External links ==
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Official website
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data/en.wikipedia.org/wiki/Carnot_engine_explanation-0.md
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title: "Carnot engine explanation"
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source: "https://en.wikipedia.org/wiki/Carnot_engine_explanation"
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category: "reference"
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In 1824 the French military engineer Sadi Carnot laid the foundations of the science of thermodynamics by describing the unsurpassably efficient Carnot engine. His insight has been described as "real genius" and compared to Einstein's, Newton's and Galileo's. Carnot wrote in clear and popular language and meant his theory to be easy to understand. Yet it has been found that, as taught in many academic courses, students have difficulty intuiting his ideas. This article is an introduction for non-specialists.
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The efficiency of the ideal, or Carnot, engine is surprisingly low. That of real heat engines is worse.
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== Significance ==
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=== Importance ===
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Carnot's innovation has been described as "real genius" and "one of the greatest intellectual achievements of the human mind". For Nobel laureate Richard FeynmanThe science of thermodynamics began with an analysis, by the great engineer Sadi Carnot, of the problem of how to build the best and most efficient engine. In particular it led to the discovery of the Second Law, of which it has been claimed that "Not knowing the Second Law of Thermodynamics is equivalent to never having read a work by Shakespeare".
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=== Clarity ===
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Sadi Carnot died young and published only one work: Reflections on the Motive Power of Fire (1824). A short book addressed to practical engineers in popular language, it has been described as "remarkably accessible to modern readers"; "very clearly written ... [the] mathematical arguments are consigned to footnotes". It is known that Carnot was anxious to be understood by non-specialists. Yet, in many university courses the Carnot cycle it is introduced in such an abstract way that students have trouble intuiting his ideas, and their implications.
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Not all approve of his popular exposition. In The Tragicomical History of Thermodynamics 1822-1854 Clifford Truesdell strongly criticised Carnot for his lack of mathematical rigour, which (he said) has affected the discipline ever since.
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=== Flaw in theory, and rescue ===
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Carnot's theory as published contains a serious flaw, which he increasingly came to suspect himself. Like many scientists of his time he had assumed heat was an actual substance (they called it caloric). This is an intuitive way to think about heat and it has been shown that children think similarly.
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After Carnot's death new data led to a fundamental shift in scientific thinking. Heat is now usually described as a form of energy, which can be converted into mechanical work, and vice versa. Carnot's theory was eventually rescued by Rudolf Clausius and (independently) William Thomson (Lord Kelvin), who made the necessary corrections. Today most students are taught not Carnot's theory but the rescued version. If Carnot's version is taught first it is easier to understand. This detail will be explained later.
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== Context and motivation ==
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Carnot's motivation was practical. "The purpose of Reflexions was to bring to public notice the potential of the steam engine for improving the standard of living in France".
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The first useful steam engines were developed in Britain and were typically employed for pumping water out of coal mines. Since an engine could burn the mine's own coal (including waste coal, which had no commercial value) fuel economy was of little concern. The incentive to have efficient engines arose in parts of the country where fuel was costly, such as Cornwall.
|
||||
The mines of Cornwall produced useful metals like tin; but not coal. The fuel to power their pumping engines had to be imported by sea and was expensive; users were keenly aware that "heat cost money". They sought the engine that did the best "duty'", measured in millions of pounds of water lifted one foot high per bushel of coal burnt. A practical business measure, it was a crude indication of the thermodynamic efficiency of an engine.
|
||||
Cornish engineers were famous for the efficiency of their engines and their achievements were studied avidly, not least in France, where coal was expensive too. Sadi Carnot's book mentioned three of them by name, Richard Trevithick, Arthur Woolf and Jonathan Hornblower. Such men developed the Cornish engine in which high pressure steam was cut off early when the piston was at the beginning of its stroke, letting the steam's expansion complete the stroke by itself. Today it might be called adiabatic expansion.
|
||||
Their ideas were enthusiastically taken up in France, where additionally, scientists and engineers were interested in the theory of steam and other engines.
|
||||
|
||||
== Carnot's aim: a general theory of engines ==
|
||||
|
||||
"Every one knows that heat can produce motion", began Carnot. Typically it was done by steam engines. Important to the Industrial Revolution, they had been vastly improved by practical British engineers, said Carnot, but without really understanding the theory of what they were doing.
|
||||
Because of the remarkable improvements that had already been made in fuel efficiency - a ten-fold increase since 1775 - it was asked whether it would go on for ever. Or would engineers run up against a fundamental limit, impossible to exceed? Matters such as these had attracted some of the ablest mathematicians and physicists in France.
|
||||
Engineers also wondered if there could be a better working substance than steam. In principle, anything that exerted a force when heated and cooled might work, even a solid metallic bar. Many substances were tried or considered, for example the Stirling engine used air. Others included alcohol, ammonia, even mercury; there were hundreds of such exotic proposals, some dangerous: there were ships and factories powered by engines that worked by boiling ether, a highly flammable liquid.
|
||||
|
||||
To answer questions such as these, said Carnot, one needed to think generally, to go beyond the details of this or that engine.It is necessary to establish principles applicable not only to steam-engines but to all imaginable heat-engines.
|
||||
For historian of science John D. Norton "it is important to realize just how audacious it was of Sadi to seek such a simple general theory, let alone to find it", for the practical engines of his day were already very complicated devices.
|
||||
48
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||||
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|
||||
title: "Carnot engine explanation"
|
||||
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|
||||
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|
||||
category: "reference"
|
||||
tags: "science, encyclopedia"
|
||||
date_saved: "2026-05-05T04:19:16.023719+00:00"
|
||||
instance: "kb-cron"
|
||||
---
|
||||
|
||||
== Preliminary outline ==
|
||||
Carnot grasped that:
|
||||
|
||||
all heat engines work by conveying heat from a hotter to a cooler place
|
||||
a heat engine may work in reverse, when it becomes a heat pump
|
||||
the ideally efficient engine would be 100% reversible and it is impossible to have an engine more efficient than that
|
||||
its working substance (steam, air or other fluid) is not critical; on the contrary, the ideal reversible engine's efficiency is limited by its input and output temperatures, and nothing else.
|
||||
He also found the cycle by which the 100% reversible engine could work. It serves as the ideal or benchmark against which all feasible heat engines can be compared.
|
||||
|
||||
== His reasoning ==
|
||||
For Edwin Thompson Jaynes
|
||||
Carnot's reasoning is outstandingly beautiful, because it deduces so much from so little — and with such a sweeping generality that rises above all tedious details — but at the same time with such a compelling logical force. In this respect, I think that Carnot's principle ranks with Einstein's principle of relativity.
|
||||
For historian of science D. S. L. Cardwell, "Nothing unnecessary is included and nothing essential is missed out. It is, in fact, very difficult to think of a more efficient piece of abstraction in the history of science since
|
||||
Galileo taught men the basis of the procedure".
|
||||
|
||||
=== 1. Heat, without a cold place, cannot generate motion ===
|
||||
Carnot showed, first, that heat by itself cannot produce motion: it must also have a cooler place to go to. The common steam engine had a hot place (the furnace) and a cool place (the condenser); but he proved the same principle must be true for all heat engines that can possibly be devised.
|
||||
He did it by imagining an engine with no cool place at all i.e. engine and surroundings are uniformly hot. Such an engine can deliver no power e.g. the piston will not retract. (As Feynman put it, "If the whole world were at the same temperature, one could not convert any of its heat energy into work".) "It is necessary that there should also be cold; without it, the heat would be useless", said Carnot. (Power station cooling towers were developed to provide such cool places, as were automobile radiators; such recipients for waste heat are called cold sinks, or more directly, heat sinks.)
|
||||
|
||||
Carnot supplied an analogy: a waterfall. He wroteThe motive power of a waterfall depends on its height and on the quantity of the liquid; the motive power of heat depends also on the quantity of caloric used, and on what ,,, we will call, the height of its fall, that is to say, the difference of temperature of the bodies between which the exchange of caloric is made.
|
||||
That heat engines cannot produce motion except by exploiting the difference in temperature between two places was not so obvious.
|
||||
The insight was afterwards used to formulate the Second Law of Thermodynamics:-
|
||||
|
||||
A ship's engine cannot extract heat from the ocean only for lack of a suitable cold sink. A small engine for polar regions has been proposed that exploits the temperature difference between the sea (just above freezing) and the much colder winter atmosphere (—25°C).
|
||||
|
||||
=== 2. A heat engine can be run in reverse and will behave as a refrigerator ===
|
||||
|
||||
==== Running an engine backwards ====
|
||||
Next, Carnot reasoned that, like a water-mill, the heat engine could be run backwards. Instead of exploiting the "fall" to get useful mechanical effort, we could do the reverse: expend the mechanical effort to drive the caloric "upwards".
|
||||
Specifically, by forcing the engine backwards, we can make heat go from the cool place to the hot place, contrary to what naturally happens. The cool place will be made even cooler (as in a refrigerator) and the hot place will be made even hotter. Carnot had invented the heat pump.
|
||||
(This insight - that it is possible to convey heat from a cool to a warm place, but only by the expenditure of mechanical effort, lies at the heart of another way of stating the Second Law of Thermodynamics.)
|
||||
|
||||
==== Reversibility as an index of efficiency ====
|
||||
Carnot then went on to develop the crucial idea that, the more efficient the engine, the greater the proportion of heat that can be recovered if run backwards.
|
||||
Historian of science D. S. L. Cardwell believed that Carnot was inspired by the column-of-water engine, an early form of hydropower. Popular in districts where coal was scarce, it was similar to a steam engine, but driven by the pressure of a head of water instead of steam. Like the steam engine, engineers strove to make it more efficient; and they expressed its efficiency in terms of the proportion of water that could be restored if run backwards, when it behaved as a pump.
|
||||
|
||||
=== 3. The ideally efficient heat engine would be completely reversible ===
|
||||
Carnot went on to prove that if a heat engine could be made completely reversible, its efficiency would be unsurpassable. It is, therefore, the fundamental limit beyond which engine efficiency cannot possibly go, answering his earlier question. Today this engine is called the Carnot engine in his honour. When it is run in reverse, it consumes as much motive power as it generates when it is run forward.
|
||||
51
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|
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title: "Carnot engine explanation"
|
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|
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category: "reference"
|
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tags: "science, encyclopedia"
|
||||
date_saved: "2026-05-05T04:19:16.023719+00:00"
|
||||
instance: "kb-cron"
|
||||
---
|
||||
|
||||
The Carnot engine is not one anyone would attempt to build. Its point is that it represents the ideal or extreme limit which cannot be surpassed even in theory. It is a benchmark against which all real engines can be compared. For example, solar cells are heat engines, and "Carnot efficiency appears profusely in the numerous formulae that have been suggested for solar energy conversion".
|
||||
For Carnot, a completely reversible engine has this property. Run forwards as a motor, one cycle can lift a weight a certain distance [generate a certain amount of work] while transferring a certain amount of heat from the hot place to the cool place. Run backwards as a refrigerator, one cycle will exactly restore the original conditions. All real engines fall short of this ideal standard, since along the way they lose a fraction of the heat.
|
||||
The proof is as follows. Suppose there was such a thing as a 'super' engine: one even more efficient than a Carnot engine. Then we could use it to drive a Carnot engine backwards. The Carnot engine would restore the heat from cold to hot place. In effect, the imaginary super engine would be delivering a margin of useful power while using the Carnot engine to feed itself an inexhaustible supply of fuel. Wrote one commentator: "Once started, this would run forever, delivering an infinite amount of useful work without any further expenditure of fuel". We would have perpetual motion to "drive our ships, locomotives and factories".
|
||||
Since this is absurd and inadmissible, we must conclude that the supposed super engine cannot exist. Hence
|
||||
|
||||
Physicist Sir Joseph Larmor thought this argument "is perhaps the most original in physical science".
|
||||
|
||||
=== 4. It does not depend on finding a superlative working substance ===
|
||||
|
||||
It follows at once that all engines, if reversible, must have the same efficiency if operating between those temperatures, regardless of their working substances. It cannot depend on the working substance, for in the above proof none was specified: it might have been steam, air, or anything else.
|
||||
(That all reversible engines working between the same heat source and cool place have the same efficiency is yet another way of stating the Second Law of Thermodynamics, and many authors have credited the law to Sadi Carnot himself.)
|
||||
Therefore, advised Carnot, there was little to be gained by experimenting with exotic substances, for none was intrinsically more efficient. As a practical matter the only promising substitute for steam was air, because "Air could be heated directly by combustion carried on within its own mass" — in other words, the internal combustion engine.
|
||||
Rather, the guiding principle in practical engine design should be that the temperature of the working fluid should fall from as high as possible to as low as possible, acting expansively.
|
||||
|
||||
=== 5. The Carnot cycle ===
|
||||
To make his proof more rigorous he went on to describe an engine actually working between a hot reservoir and cold sink in a completely reversible cycle. For this to happen each step in the cycle had itself to be reversible i.e. it must not waste any fraction of the heat.
|
||||
|
||||
==== Means ====
|
||||
|
||||
The fundamental rule for not wasting heat, deduced Carnot (see quote box), is never to allow direct thermal contact between parts which are at appreciably different temperatures. Were that to permitted, heat would escape from hotter to cooler: without doing any work.
|
||||
Very few thermodynamic processes can be carried out without breaking that rule. For instance, if we wanted to expand a body of gas in a cylinder to drive a piston, we would normally just heat it up: but this would require thermal contact with something hotter.
|
||||
However, there are two extreme cases in which it is just possible in principle:
|
||||
|
||||
Completely insulate the body of gas and allow it to expand spontaneously from its own internal energy; this will lower its temperature. The jargon for this is adiabatic expansion. (The idea was used in the Cornish engine, above.)
|
||||
Apply heat to the body of gas so slowly that it has time to expand without raising its temperature. For this to happen, the temperature gap between gas and heat source must be infinitesimal. The jargon for this is isothermal expansion.
|
||||
The problem is to combine them into a working, reversible cycle.
|
||||
|
||||
==== Realization ====
|
||||
To retract the piston and exactly restore the initial conditions, the same processes are to be used in reverse viz. isothermal compression and adiabatic compression.
|
||||
Hence his cycle can be analyzed into four steps. In the isothermal phases, more energy is produced in the (hot) expansion stroke than is consumed in the (cool) compression stoke. The adiabatic phases exactly cancel out. So the net balance is positive.
|
||||
The Carnot Cycle is illustrated in the animation; and since it is completely reversible, by Carnot's Principle its efficiency must be the best that can be achieved.
|
||||
It is usual nowadays when drawing the Carnot cycle to include a pressure–volume diagram with associated mathematics. This was not done by Carnot himself and is not necessary for an intuitive understanding of his ideas.
|
||||
For James Clerk Maxwell
|
||||
|
||||
The great merit of Carnot's method is that he arranges his operations in a cycle, so as to leave the working substance in precisely the same condition as he found it. We are therefore sure that the energy remaining in the working substance is the same in amount as at the beginning of the cycle.
|
||||
greatly simplifying any calculations, since we only have to compare the heat taken in, the heat given out, and the work done by the engine
|
||||
Maxwell also showed that a simple adjustment to the cycle can correct the flaw in Carnot's theory; see below.
|
||||
|
||||
== A scientific revolution seems to invalidate Carnot's work ==
|
||||
|
||||
=== Caloric, the established theory ===
|
||||
40
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|
||||
title: "Carnot engine explanation"
|
||||
chunk: 4/8
|
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|
||||
category: "reference"
|
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tags: "science, encyclopedia"
|
||||
date_saved: "2026-05-05T04:19:16.023719+00:00"
|
||||
instance: "kb-cron"
|
||||
---
|
||||
|
||||
For most scientists of Carnot's time the best explanation of heat was the caloric theory. It held that heat is a material fluid that can flow from one place to another: its temperature may vary, but it can never itself be destroyed nor created.
|
||||
The caloric theory was highly developed, mathematically sophisticated, and plausible. The alternative theory, that heat consists in the agitation of a substance's particles — in modern terms, energy — was well known, but did not command much support, mainly for lack of convincing experimental evidence. For historian of science Thomas Kuhn, "To analyze the gas engine Carnot required a developed theory of heat, and in the 1820's the caloric theory was the only one at hand".
|
||||
Several authors have speculated that without the caloric theory and his waterfall analogy Carnot would not have been led to his discovery.
|
||||
Pursuant to this core idea, Carnot taught that all heat entering his engine from the hot source must fall out into the cold sink. But according to new ideas — that were dawning on Carnot himself, and came to be adopted overwhelmingly — this is false. Some of the heat will be consumed on the way: by the doing of work.
|
||||
|
||||
=== A new outlook ===
|
||||
From 1800 new discoveries started to emerge — e.g. the galvanic battery, heat by electricity, electrolysis, electromagnetism, induced currents, thermoelectric cooling — which increasingly suggested that a single "force", nowadays called energy, was manifesting itself in different ways. According to Thomas Kuhn, the interconnection between previously detached branches of science was going on apace "and that is what Mary Somerville had in mind when, in 1834, she gave her famous popularization of science the title On the Connexion of the Physical Sciences".
|
||||
|
||||
For Kuhn, "Mrs. Somerville's remark isolates the 'new look' that physical science had acquired between 1800 and 1835. That new look, together with the discoveries that produced it, proved to be a major requisite for the emergence of
|
||||
energy conservation."
|
||||
|
||||
=== Energy, not heat, is conserved ===
|
||||
Within the space of a few years perhaps a dozen scientists, largely working independently, became convinced that heat and work are mutually interchangeable (always at same rate of exchange, which they were able to calculate). Four of them formally published their claims, supported by data: Julius von Mayer (Württemberg), James Prescott Joule (England), Ludwig A. Colding (Denmark) and Hermann von Helmholtz (Prussia). Joule's experimental proof was particularly copious.
|
||||
|
||||
There is "no more striking instance" of simultaneous discovery in the history of science, wrote Thomas Kuhn. It was not heat that was conserved, but a more general thing: energy. Heat was just one manifestation of energy.
|
||||
|
||||
==== Obscurity ====
|
||||
|
||||
One of the first to come round to the dynamical theory of heat, as it was called, had been Sadi Carnot himself. From surviving notes it is known he started to have doubts about the caloric theory and, according to physicist Eric Mendoza, "by the time he came to correct the proofs of his book he had realized that the very basis of all his theorems and demonstrations was wrong". He did not live to solve the problem and publish that. It was a "sad fact that he died in a madhouse": in 1832.
|
||||
His book made no discernible impact on the scientific or engineering communities of the time. One person who did read it was his friend Émile Clapeyron who rewrote the theory in a mathematical treatment and published it in a learned journal; it was translated into English.
|
||||
Sadi Carnot's book fell into such obscurity that in 1845 William Thomson (the future Lord Kelvin), then a research student in Paris, was unable to find a copy. "He searched libraries, bookstores, and the stalls on the quays along the Seine, but no success... Sadi Carnot on heat was unknown".
|
||||
|
||||
== Rescuing Carnot's theory ==
|
||||
|
||||
=== Rudolf Clausius and William Thomson ===
|
||||
Eventually Thomson did manage to get hold of a copy: in his native Scotland. He published papers about Carnot's theory that drew it to the attention of scientists generally. It contained some important truths. Using it, Thomson was able to devise the Kelvin scale of temperature, and his brother James Thomson used it to make an important prediction about the freezing point of water under pressure that was verified experimentally. Hence Thomson was extremely reluctant to give up the caloric theory, even though his friend Joule was insisting it was wrong.
|
||||
|
||||
Around 1850 Rudolf Clausius (Berlin, Prussia) and William Thomson (Glasgow, Scotland) independently realised that Carnot's theory could be saved by making a new assumption about the laws of physics. Of the two, Clausius published first; Thomson conceded his priority. Their papers can be read as external links to this article. Their reasoning becomes increasingly mathematical but the key point is paraphrased later below.
|
||||
|
||||
=== Fixing the Carnot cycle: Maxwell ===
|
||||
48
data/en.wikipedia.org/wiki/Carnot_engine_explanation-4.md
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||||
---
|
||||
title: "Carnot engine explanation"
|
||||
chunk: 5/8
|
||||
source: "https://en.wikipedia.org/wiki/Carnot_engine_explanation"
|
||||
category: "reference"
|
||||
tags: "science, encyclopedia"
|
||||
date_saved: "2026-05-05T04:19:16.023719+00:00"
|
||||
instance: "kb-cron"
|
||||
---
|
||||
|
||||
The Carnot cycle as published cannot work since it is wrongly assumed that as much heat should be expelled to the cold sink as came in from the hot source. That is too much: not enough will be left in the engine to complete the cycle. A simple way to correct the mistake was described by James Clerk Maxwell in his Theory of Heat (1871). This was a book meant for "artisans and students" but Maxwell "did not hesitate to include discussions of the latest work in thermodynamics".
|
||||
By that date French engineer Gustave-Adolphe Hirn had confirmed by experiment that, whenever an engine performs mechanical work, less heat emerges from it than goes in. The missing heat is changing into work.
|
||||
But it was easy to see that the quantities (heat in vs. heat out) could not have been equal, said Maxwell. For, supposing they were, how could we explain that the engine, by doing work, can produce yet more heat — e.g. by stirring a liquid to raise its temperature? In that case the engine must somehow be producing more heat than it consumes, contrary to the doctrine that caloric cannot be created.
|
||||
To fix the Carnot cycle, therefore, one must terminate the isothermal compression phase at just the right point, before too much heat has passed to the cold sink. It is easy to do this by calculation, said Maxwell, "but is still easier" by removing the sink as soon as the fluid pressure rises to its original cold-temperature value.
|
||||
|
||||
=== Fixing the proof ===
|
||||
A deeper problem was that Carnot's proof of his central Principle was not valid either. Granted the conservation of heat, he had reasoned (above) that there could not be such a thing as a 'super' engine more efficient than a Carnot engine, or else perpetual motion would be possible. However, as Ted Jacobson noted
|
||||
While Carnot's conclusion was correct, his argument contained a single deep flaw: heat is not by itself conserved! More heat flows out of the hot reservoir than flows into the colder reservoir, the difference being the work extracted.
|
||||
This means that, since the 'super' engine is the more efficient of the two, it extracts more work and so passes less waste heat into the cold reservoir. Hence, when the Carnot engine is run backwards, "the cold reservoir is no longer restored to its initial state: more heat is drawn out than went in".
|
||||
|
||||
The leftover work, then, is not produced from nothing, but rather from the heat drawn out of the colder reservoir. While not as inadmissable [i.e. intentionally absurd] as Carnot's result, this is nevertheless inadmissable. Its impossibility is Kelvin's version of the second law of thermodynamics.
|
||||
There is another way of looking at it:
|
||||
Alternatively, all of the work from the more efficient engine could be used to run the less efficient engine backwards, in which case the net result would be spontaneous (but engineered) heat flow from the colder reservoir to the hotter one, in violation of Clausius' version of the second law.
|
||||
|
||||
== Aftermath ==
|
||||
|
||||
=== The Second Law ===
|
||||
|
||||
Hence, Kelvin and Clausius saved the Carnot Principle by formally identifying and stating new laws of nature. The First Law of Thermodynamics is the conservation of energy. The Second Law can be encapsulated thus:
|
||||
|
||||
Heat cannot flow spontaneously from cold to hot (Clausius).
|
||||
An engine cannot be run from a single heat reservoir (Kelvin)
|
||||
Those are similar formulations; were long believed to be completely equivalent; but turn out not to be quite the same. A disquieting feature, which has still not been explained, is that there is no universally agreed way of stating this law, despite attempts at consensus. There have been many formulations. "And even today, the Second Law remains so obscure that it continues to attract new efforts at clarification".
|
||||
|
||||
==== Engineering in spite of the Second Law ====
|
||||
|
||||
Only slowly did the new theory diffuse into engineering practice, and reputable technologists continued to conceive engines that were thermodynamically impossible. John Ericsson built a hot air ship's engine that (it was claimed) saved fuel by continually recycling waste heat. Called the Caloric Engine, its cylinders were 14 foot (4.3 metres) thick. According to one who believed in it:
|
||||
The principle of this new engine consists in this, that the heat which is required to give motion to the engine at the commencement, is returned by a peculiar process of transfer, and thereby made to act over and over again, instead of being, as in the steam engine, thrown into a condenser, or into the atmosphere as so much waste fuel.To which Scientific American riposted: "Let us point out its fallacious principles: it is stated that it only uses so much coal to make up the loss of radiation, therefore, if there were no loss of heat by radiation, it would use no coai at all, after the first fire; it would go on for ever — a perpetual motion surely".
|
||||
|
||||
==== Entropy ====
|
||||
|
||||
Sadi Carnot's most important single idea may have been the completely reversible thermodynamic process. It led to the concept of entropy, whose meaning is indicated below.
|
||||
The word entropy ("transformational energy") was coined by Clausius in 1865 to refer to a variable in his mathematical reasoning. It stands for something that is expressed in units of energy divided by temperature, is not directly apprehended by the human senses, and is difficult to measure experimentally, Generally, there exists a rather hazy understanding of entropy, even amongst those who have to use the concept professionally. Also the word is much misused by some scientists, educators and popular writers, if not abused by charlatans.
|
||||
In the same paper Clausius summarised the laws of thermodynamics as follows:
|
||||
|
||||
The energy of the universe is constant.
|
||||
The entropy of the universe tends to a maximum.
|
||||
One way of understanding 2. is as follows:
|
||||
56
data/en.wikipedia.org/wiki/Carnot_engine_explanation-5.md
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|
||||
title: "Carnot engine explanation"
|
||||
chunk: 6/8
|
||||
source: "https://en.wikipedia.org/wiki/Carnot_engine_explanation"
|
||||
category: "reference"
|
||||
tags: "science, encyclopedia"
|
||||
date_saved: "2026-05-05T04:19:16.023719+00:00"
|
||||
instance: "kb-cron"
|
||||
---
|
||||
|
||||
Another way to think about entropy is as a measurement of the availability of useful energy in a system. While energy cannot be created or destroyed, as the approaches equilibrium the energy of that system becomes less available for use.
|
||||
The concept entropy, though important in thermodynamics, is not necessary for an intuitive understanding of Carnot's theory. There are many formulations of the Second Law that do not mention entropy at all, including the original Clausius and Thomson versions.
|
||||
|
||||
== Efficiency ==
|
||||
It is sometimes stated that Carnot gave the formula for the efficiency of his engine. He could not have done, since his theory did not embrace the First Law of Thermodynamics, not then known. Carnot himself was able to state that it depended on the temperature difference between the hot source and cold sink, and the temperature of the cold sink.. But he did not give the explicit formula.
|
||||
The efficiency even of the ideal or Carnot engine turns out to be surprisingly poor, and therefore, that of real engines is even worse. It has been said that the Second Law of Thermodynamics imposes an "energy tax", payable to Nature, every time heat is converted to work.
|
||||
|
||||
=== Of the Carnot engine ===
|
||||
The Carnot engine's efficiency depends on only two temperatures and its calculation is simple. It can be considered in terms of the fraction of heat that goes down the cold sink instead of being converted to work — the "energy tax" that must be paid to nature.
|
||||
This fraction is simply the temperature of the cold sink divided by the temperature of the hot sink; they must be measured in degrees kelvin. (On this scale 0 °K is absolute zero. Fahrenheit or Celsius temperatures would give erroneous results since these scales were arbitrarily defined.)
|
||||
For example if the hot temperature is 373 °K (water boils) and the cold temperature is 273 °K (ice melts), then 73% of the heat must go down the cold sink, an escapable fact of nature. The engine's efficiency working between those temperatures is thus only 27%.
|
||||
|
||||
=== In real time ===
|
||||
In fact, the Carnot engine cannot deliver even that performance within a realistic timescale.
|
||||
Of the four phases of the Carnot cycle, the two isothermals must be performed extremely slowly. (If not, there would be an appreciable temperature gradient, implying heat loss and irreversibility, see above.) But this means that the engine takes infinite time to perform a cycle, or put crudely, it never does.
|
||||
If the engine is to operate in real time, it becomes necessary to sacrifice some of its reversibility. It then develops real power, but it is no longer a true Carnot engine, and its efficiency is less.
|
||||
It has been calculated that the fraction of waste heat down the cold sink then is, not the ratio of the two temperatures (as above), but the square root of that number.
|
||||
This result was derived by Curzon and Ahlborn — though they were not the first to do so — who claimed that it more closely predicts the performance of real thermal generators.
|
||||
For example, if working between given temperatures a Carnot engine loses 1/4 of its heat down the cool sink, it will lose 1/2 in real time operation.
|
||||
|
||||
=== All practical heat engines are worse ===
|
||||
|
||||
The Carnot engine is supposed to be frictionless and have perfect insulation or conduction where required. Real engines can never match these criteria and their efficiency is poorer. Further, the hot temperature cannot be made extremely high, for practical materials reasons, and the cold temperature can rarely be made very low.
|
||||
|
||||
==== Materials limitations ====
|
||||
For example, in the first commercial nuclear power stations the fuel rods could not operate above 450 °C for fear of melting the Magnox cladding. The thermal efficiency was 23%. Later alloys allowed the temperature to be raised to 640 °C, which could deliver a thermal efficiency of 41%.
|
||||
|
||||
==== The steam locomotive ====
|
||||
A good cold sink is needed for efficiency. In the traditional steam railway locomotive such was lacking, since it had no condenser, and simply vented waste steam into the atmosphere. It turned only 4% of its heat into mechanical work. The rest went "straight to heat up the countryside".
|
||||
|
||||
==== Cars and trucks ====
|
||||
Car engines can have efficiencies of 20% or less, compared to their Carnot Limit of 37%. The highest efficiency for a commercial vehicle diesel engine (2021) was claimed to be 50%.
|
||||
|
||||
==== Power stations ====
|
||||
According to Mitsubishi Heavy Industries, in 2022 the world's highest thermal efficiency was achieved at the Joetsu Thermal Power Station No 1, Japan, being certified by Guinness World Records. It was 63.62%.
|
||||
|
||||
==== Solar cells ====
|
||||
Solar cells are heat engines, and they start off with the advantage that the hot reservoir — the Sun — is at 6,000 °K. Assuming a good cold sink this would give a Carnot efficiency of 95%. However a solar cell is not a Carnot engine. A 2016 review found that after allowing for various losses they achieved 7-8% efficiency, though it was hoped to raise this.
|
||||
|
||||
== Public recognition ==
|
||||
Carnot has been compared to thinkers of the calibre of Euclid, Isaac Newton and Francis Bacon ("Only now and then, in the centuries, does such a genius come into view").
|
||||
But he is little known to the general public, even in his native country. In France the better known Carnots are his father, his nephew and his younger brother.
|
||||
|
||||
== Explanatory notes ==
|
||||
|
||||
== References and referenced notes ==
|
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tags: "science, encyclopedia"
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date_saved: "2026-05-05T04:19:16.023719+00:00"
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|
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|
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||||
Markvart, Tom (2016). "From steam engine to solar cells: can thermodynamics guide the development of future generations of photovoltaics?". WIREs Energy and Environment. 5 (5): 543–569. Bibcode:2016WIREE...5..543M. doi:10.1002/wene.204. Maxwell, J. Clerk (1871). Theory of Heat (1 ed.). London: Longmans Green. Retrieved 30 March 2026. Mendoza, E. (1961). "A sketch for a history of early thermodynamics" (PDF). Physics Today. 14 (2): 32–42. Bibcode:1961PhT....14b..32M. doi:10.1063/1.3057388. Retrieved 15 March 2026. Meyn, Jan-Peter (2024). "A Contemporary View on Carnot's Réflexions". Entropy. 26 (12: 1002): 1002. Bibcode:2024Entrp..26.1002M. doi:10.3390/e26121002. PMC 11675156. PMID 39766632. Norton, John D. (2022). "How analogy helped create the new science of thermodynamics". Synthese. 200 (4) 269: 1–42. doi:10.1007/s11229-022-03708-9. JSTOR 27324886. Nuvolari, Alessandro; Verspagen, Bart (2005). ""Unravelling the duty": Lean's Engine Reporter and Cornish Steam Engineering". Eindhoven Centre for Innovation Studies Working Paper Series. 200514. Retrieved 4 December 2025. Nuvolari, Alessandro (2010). "The theory and practice of steam engineering in Britain and France, 1800-1850". Documents pour l'histoire des techniques [En ligne]. 19: 189–197. doi:10.4000/dht.1439. hdl:11382/305525. Retrieved 5 December 2025. Ortner, Susan (2023). "A review of structural material requirements and choices for nuclear power plant". Frontiers in Nuclear Engineering. 2 (1253974) 1253974: 1–11. doi:10.3389/fnuen.2023.1253974. Perrin, C.E. (1973). "Lavoisier's Table of the Elements: A Reappraisal". Ambix. 20 (2): 95–105. doi:10.1179/amb.1973.20.2.95. Pole, William (1844). A Treatise on the Cornish Pumping Engine. London: John Weale. Retrieved 12 December 2025. Popovic, Marko (2017). "Researchers in an entropy wonderland: A review of the entropy concept". arXiv. arXiv:1711.07326. Raviv, Daniel; Barb, Daniel Ryan (2020). "A Visual and Intuitive Approach to Teaching and Learning the Concept of Thermodynamic Entropy". ASEE Virtual Annual Conference Content Access. American Society for Engineering Education. Scientific American (29 January 1853). "Ericsson's Caloric Engine". Scientific American. pp. 153–5. Retrieved 12 April 2026. Scoltock, James (25 February 2021). "Bosch and Weichai Power boost diesel engine thermal efficiency". London: Institution of Mechanical Engineers. Retrieved 15 February 2026. Shedd, John C. (1899). "A Mechanical Model of the Carnot Engine". The Physical Review. VIII (LXII): 174–180. Retrieved 7 December 2025. Smith, T.I.; Christensen, W.M.; Mountcastle, D.B.; Thompson, J.R. (2015). "Identifying student difficulties with entropy, heat engines, and the Carnot cycle". Physical Review Special Topics—Physics Education Research. 11 (2) 020116. arXiv:1508.04104. Bibcode:2015PRPER..11b0116S. doi:10.1103/PhysRevSTPER.11.020116. Retrieved 5 December 2025. Taylor, C.R. (1980). "Mechanical efficiency of terrestrial locomotion: a useful concept?". In H.Y. Elder; E.R. Trueman (eds.). Aspects of Animal Movement. Cambridge University Press. pp. 235–244. ISBN 0-521-23086-1. Thomson, William, Sir [Lord Kelvin] (1882). Mathematical and Physical Papers. Vol. I. Cambridge University Press. Retrieved 7 April 2026.{{cite book}}: CS1 maint: multiple names: authors list (link)
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||||
Thurston, R.H. (1897). "The Work of N.-L. Sadi Carnot". In Thurston, R.H. (ed.). Reflections on the Motive Power of Heat (2nd ed.). New York: John Wiley & Sons. Retrieved 6 December 2025. Tribus, Myron (1959). Thermostatics and Thermodynamics. Vol. 2. Van Nostrand. Truesdell, Clifford Ambrose (1980). The Tragicomical History of Thermodynamics 1822-1854. New York and Heidelberg: Springer-Verlag. ISBN 0-387-90403-4. Tsoukalas, Lefteri H. (2026). Energy Transitions: The AI–Energy Nexus. World Scientific. doi:10.1142/9789819820443_0001. Uffink, Jos (2001). "Bluff your way in the second law of thermodynamics". Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics. 32 (3): 305–394. arXiv:condmat/0005327. Bibcode:2001SHPMP..32..305U. doi:10.1016/S1355-2198(01)00016-8. Wilson, S.S. (1981). "Sadi Carnot". Scientific American. 245 (2): 134–145. Bibcode:1981SciAm.245b.134W. doi:10.1038/scientificamerican0881-134. JSTOR 24964543. Zemansky, Mark W. (1957). Heat and Thermodynamics (4th ed.). McGraw-Hill.
|
||||
|
||||
== External links ==
|
||||
Sadi Carnot Reflections on the Motive-Power of Heat, and on Machines Fitted to Develop that Power, 1824 (Thurston translation)
|
||||
James Prescott Joule On the Calorific Effects of Magneto-Electricity, and on the Mechanical Value of Heat, 1843
|
||||
Rudolf Clausius On the Motive Power of Heat, and on the Laws which can be Deduced from it for the Theory of Heat, 1850 (Magie translation)
|
||||
William Thomson (Lord Kelvin) On the Dynamical Theory of Heat, with numerical results deduced from Mr Joule's Equivalent of a Thermal Unit, and M. Regnault's Observations on Steam, 1851
|
||||
James Clerk Maxwell On Heat Engines (from his Theory of Heat, 1871)
|
||||
Joseph Larmor's On the Nature of Heat, as Directly Deducible from the Postulate of Carnot, 1918. (Carnot's theory deduced without making the erroneous conservation of heat assumption.)
|
||||
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|
||||
---
|
||||
title: "Center for Advanced Materials"
|
||||
chunk: 1/1
|
||||
source: "https://en.wikipedia.org/wiki/Center_for_Advanced_Materials"
|
||||
category: "reference"
|
||||
tags: "science, encyclopedia"
|
||||
date_saved: "2026-05-05T04:19:17.291987+00:00"
|
||||
instance: "kb-cron"
|
||||
---
|
||||
|
||||
The Center for Advanced Materials (CAM) is a research center at Qatar University that hosts faculty members and researchers involved in advanced materials research. It provides the opportunities for collaborative research projects between academic and industry experts, as well between faculty members and students. The Center for Advanced Materials works under Qatar University's Office of Vice President for Research and Graduate Studies. CAM's research clusters are broadly grouped into the following areas: Metallurgy, Sustainable Materials, Corrosion, Polymer Materials and Renewable Energy Resources.
|
||||
In 2022, the UNESCO established a Chair on desalination at Qatar University and hosted in CAM to study water security in the Gulf region and to adapt to drought due to climate changes; The Chair contributes to capacity development to meet the UN SDG6.
|
||||
|
||||
|
||||
== References ==
|
||||
|
||||
|
||||
== External links ==
|
||||
Qatar University
|
||||
Qatar University Newsroom
|
||||
Center for Advanced Materials
|
||||
WISE Initiative
|
||||
42
data/en.wikipedia.org/wiki/Clubes_de_Ciencia-0.md
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|
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title: "Clubes de Ciencia"
|
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|
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|
||||
category: "reference"
|
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tags: "science, encyclopedia"
|
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date_saved: "2026-05-05T04:19:18.546968+00:00"
|
||||
instance: "kb-cron"
|
||||
---
|
||||
|
||||
Clubes de Ciencia is a non-profit organization founded in 2014 that organizes hands-on week-long workshops in STEM to kids in developing countries at no cost. The instructors are PhD volunteers from top universities, such as Harvard, Princeton, MIT who organizes the workshops. By combining hands-on experimental learning, on-line exercises and mentorship, Clubes de Ciencia takes a unique approach to educating the millennials in developing countries. In two years, Clubes de Ciencia grew past its Mexico program, to also work in Colombia and Bolivia. Currently, it also operates in Brazil, Paraguay, Peru and Spain.
|
||||
|
||||
|
||||
== 2014 ==
|
||||
The first edition of Science Clubs was organized in Guanajuato, Mexico, in January 2014, with the support of Universidad de Guanajuato.
|
||||
|
||||
|
||||
== 2017 ==
|
||||
In 2017, Science Clubs expanded to three new countries: Paraguay, Peru and Brazil [1]
|
||||
The first edition of the Brazilian Chapter (Clubes de Ciência Brasil) was held at Universidade Federal de Minas Gerais, in Belo Horizonte, in July 2017. Four clubs in the areas of epidemiology, stem cells and gene editing, immunology and entrepreneurship were organized by researchers from top Universities from the US and Brazil, including Harvard, Northeastern and UFMG for 80 students from six different states of the country.
|
||||
|
||||
|
||||
== Prizes and awards ==
|
||||
On April 15, 2015, the Latin American Science Education Network (now Science Clubs International) was among the winners of the MIT "IDEAS" Global Challenge Awards.
|
||||
Also in 2015, Mohammed Mostajo-Radji, as Executive Director of Clubes de Ciencia Bolivia was awarded the "Person of the Year" award by the Bolivian newspaper El Deber and the Franz Tamayo Medal by the Senate of Bolivia.
|
||||
In 2016, Hugo Arellano-Santoyo and Clubes de Ciencia were awarded with the Dean's Community Service Award from the Harvard Medical School. The prize is awarded "to recognize individuals whose dedication and commitment to community service have made a positive impact on the local, national, or international community".
|
||||
In 2016, Maier Avendano, Executive Director of Clubes de Ciencia Colombia was named among the "Latino 30 under 30" by the El Mundo Boston. Mohammed Mostajo-Radji and the team of Clubes de Ciencia Bolivia received this award in 2017. Since its first version in 2015, 722 volunteer scientists living abroad or in Colombia have collaborated to create 364 clubs with the participation of 9,295 students. We describe elements of the SCC program that lead to a scalable and reproducible outcome to engage science diasporas in STEAM education in this scientific paper published in Frontiers:
|
||||
Additionally in 2016, Clubes de Ciencia Bolivia was awarded the Youth Peace Prize by the Government of Santa Cruz, Bolivia.
|
||||
In 2018, Clubes de Ciencia Bolivia received the Melchor Pinto Parada award from the Government of Santa Cruz. This is the maximum award granted by this institution. Also in 2018, Omar Gandarilla, as Operations Director of Clubes de Ciencia Bolivia received the "Diversity in STEM" award from MiniPCR.
|
||||
In 2019, under the leadership of Dr Bryann Avendaño-Uribe, Clubes de Ciencia Colombia was named "Solution Makers" by the United Nations Foundation at the United Nations Solution Summit in the General Assembly of the United Nations in New York, USA.
|
||||
In 2023, HundrED selected Clubes de Ciencia International as one of the top 100 global education innovations, highlighting its impact on STEM education in Latin America.
|
||||
|
||||
|
||||
== Partners ==
|
||||
The David Rockefeller Center for Latin American Studies, the Department of Molecular and Cellular Biology at Harvard University, the Harvard Stem Cell Institute, COMEXUS and the Fundación México en Harvard University are among the key sponsors of the project.
|
||||
|
||||
|
||||
== Endorsements ==
|
||||
Clubes de Ciencia has been endorsed by a number of academics and celebrities, including 2004 Nobel Laureate Frank Wilczek; Margot Gill, Dean of International Affairs at Harvard University and Beakman.
|
||||
|
||||
|
||||
== References ==
|
||||
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