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  2. Scanning transmission electron microscopy - Wikipedia

    en.wikipedia.org/wiki/Scanning_transmission...

    The first STEM was built in 1938 by Baron Manfred von Ardenne, [2] [3] working in Berlin for Siemens.However, at the time the results were inferior to those of transmission electron microscopy, and von Ardenne only spent two years working on the problem.

  3. List of physics concepts in primary and secondary education ...

    en.wikipedia.org/wiki/List_of_physics_concepts...

    "High school physics textbooks" (PDF). Reports on high school physics. American Institute of Physics; Zitzewitz, Paul W. (2005). Physics: principles and problems. New York: Glencoe/McGraw-Hill. ISBN 978-0078458132

  4. Federal Board of Intermediate and Secondary Education

    en.wikipedia.org/wiki/Federal_Board_of...

    The FBISE was established under the FBISE Act 1975. [2] It is an autonomous body of working under the Ministry of Federal Education and Professional Training. [3] The official website of FBISE was launched on June 7, 2001, and was inaugurated by Mrs. Zobaida Jalal, the Minister for Education [4] The first-ever online result of FBISE was announced on 18 August 2001. [5]

  5. Post-transcriptional modification - Wikipedia

    en.wikipedia.org/wiki/Post-transcriptional...

    The pre-mRNA processing at the 3' end of the RNA molecule involves cleavage of its 3' end and then the addition of about 250 adenine residues to form a poly(A) tail.The cleavage and adenylation reactions occur primarily if a polyadenylation signal sequence (5'- AAUAAA-3') is located near the 3' end of the pre-mRNA molecule, which is followed by another sequence, which is usually (5'-CA-3') and ...

  6. Gauge fixing - Wikipedia

    en.wikipedia.org/wiki/Gauge_fixing

    The Coulomb gauge (also known as the transverse gauge) is used in quantum chemistry and condensed matter physics and is defined by the gauge condition (more precisely, gauge fixing condition) (,) =. It is particularly useful for "semi-classical" calculations in quantum mechanics, in which the vector potential is quantized but the Coulomb ...

  7. Epigenetics in stem-cell differentiation - Wikipedia

    en.wikipedia.org/wiki/Epigenetics_in_stem-cell...

    Embryonic stem cells exhibit dramatic and complex alterations to both global and site-specific chromatin structures. Lee et al. performed an experiment to determine the importance of deacetylation and acetylation for stem cell differentiation by looking at global acetylation and methylation levels at certain site-specific modification in histone sites H3K9 and H3K4.

  8. Observer effect (physics) - Wikipedia

    en.wikipedia.org/wiki/Observer_effect_(physics)

    In physics, the observer effect is the disturbance of an observed system by the act of observation. [1] [2] This is often the result of utilising instruments that, by necessity, alter the state of what they measure in some manner. A common example is checking the pressure in an automobile tire, which causes some of the air to escape, thereby ...

  9. Particle physics - Wikipedia

    en.wikipedia.org/wiki/Particle_physics

    Particle physics or high-energy physics is the study of fundamental particles and forces that constitute matter and radiation. The field also studies combinations of elementary particles up to the scale of protons and neutrons , while the study of combination of protons and neutrons is called nuclear physics .