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Topic Review
Chromatin Architecture and Damage Response
DNA double-strand breaks (DSBs) have been recognized as the most serious lesions in irradiated cells. While several biochemical pathways capable of repairing these lesions have been identified, the mechanisms by which cells select a specific pathway for activation at a given DSB site remain poorly understood. The impact of chromatin and repair foci architecture on these mechanisms can be elucidated by super-resolution microscopy in combination with mathematical approaches of topology. These aspects are discussed in relation to state of the art knowledge of ionizing radiation induced damaging of cell nuclei and DNA repair.
  • 880
  • 20 Feb 2021
Topic Review
K-Theory
In string theory, K-theory classification refers to a conjectured application of K-theory (in abstract algebra and algebraic topology) to superstrings, to classify the allowed Ramond–Ramond field strengths as well as the charges of stable D-branes. In condensed matter physics K-theory has also found important applications, specially in the topological classification of topological insulators, superconductors and stable Fermi surfaces ((Kitaev 2009), (Horava 2005)).
  • 880
  • 30 Nov 2022
Biography
Leland John Haworth
Leland John Haworth (July 11, 1904 – March 5, 1979) was an United States of America particle physicist. In his long career he was head of the Brookhaven National Laboratory, the Atomic Energy Commission, the National Science Foundation, and was assistant to the president of Associated Universities, Inc.[1] Haworth was born in Flint, Michigan, although his parents were normally living in New
  • 875
  • 27 Dec 2022
Topic Review
Area Codes
Today, the North American Numbering Plan continues to create new area codes as demand increases for local lines in cities and regions nationwide. When a new area code is added, customers
  • 868
  • 26 Aug 2024
Biography
Jürgen Kurths
Jürgen Kurths (born 11 March 1953 in Arendsee/Altmark) is a German physicist and mathematician. He is a chair of the research department Complexity Sciences of the Potsdam Institute for Climate Impact Research, a Professor of Nonlinear Dynamics at the Institute of Physics at the Humboldt University, Berlin, and a 6th-century chair for Complex Systems Biology at the Institute for Complex Systems
  • 865
  • 12 Dec 2022
Topic Review
Dref Friction Spinning
Friction Spinning or Dref Spinning is a textile technology that suitable for spinning coarse counts of yarns and technical core-wrapped yarns. Dref yarns are bulky, with low tensile strength making them suitable for blankets and mop yarns, they can be spun from asbestos, carbon fibres and make filters was water systems.[clarification needed] Yarns such as Rayon and Kevlar can be spun using this method. The technology was developed around 1975 by Dr. Ernst Fehrer.
  • 861
  • 14 Oct 2022
Biography
Robert K. Logan
Robert K. Logan (born August 31, 1939), originally trained as a physicist, is a media ecologist. He received from MIT a BS in 1961 and a PhD in 1965 under the supervision of Francis E. Low. After two post-doctoral appointments as a Research Associate at the University of Illinois at Urbana-Champaign (1965-7) and the University of Toronto (1967-8), he became a physics professor in 1968 at Toro
  • 861
  • 27 Dec 2022
Topic Review
Minimal Model
In theoretical physics, a minimal model or Virasoro minimal model is a two-dimensional conformal field theory whose spectrum is built from finitely many irreducible representations of the Virasoro algebra. Minimal models have been classified and solved, and found to obey an ADE classification. The term minimal model can also refer to a rational CFT based on an algebra that is larger than the Virasoro algebra, such as a W-algebra.
  • 858
  • 17 Oct 2022
Topic Review
Plasma Medicine
Plasma medicine is an emerging field that combines plasma physics, life sciences and clinical medicine. It is being studied in disinfection, healing, and cancer. Most of the research is in vitro and in animal models. It uses ionized gas (physical plasma) for medical uses or dental applications. Plasma, often called the fourth state of matter, is an ionized gas containing positive ions and negative ions or electrons, but is approximately charge neutral on the whole. The plasma sources used for plasma medicine are generally low temperature plasmas, and they generate ions, chemically reactive atoms and molecules, and UV-photons. These plasma-generated active species are useful for several bio-medical applications such as sterilization of implants and surgical instruments as well as modifying biomaterial surface properties. Sensitive applications of plasma, like subjecting human body or internal organs to plasma treatment for medical purposes, are also possible. This possibility is being heavily investigated by research groups worldwide under the highly-interdisciplinary research field called 'plasma medicine'.
  • 856
  • 27 Oct 2022
Biography
R. Orin Cornett
R. Orin Cornett (November 13, 1913 – December 7, 2002) was an American physicist, university professor and administrator, and the inventor of a literacy system for the deaf, known as Cued Speech. R. (Richard) Orin Cornett was born in Driftwood, Oklahoma, a now unincorporated town near the Kansas border located in Alfalfa County, on November 14, 1913.[1] He earned his BS degree in Mathematic
  • 847
  • 27 Dec 2022
Topic Review
Locating an Electron with an Ideal Microscope
A photon (from grc φῶς, φωτός (Script error: No such module "Ancient Greek".) 'light') is an elementary particle that is a quantum of the electromagnetic field, including electromagnetic radiation such as light and radio waves, and the force carrier for the electromagnetic force. Photons are massless,[lower-alpha 1] so they always move at the speed of light in vacuum, 299792458 m/s (or about 186,282 mi/s). The photon belongs to the class of bosons. Like all elementary particles, photons are currently best explained by quantum mechanics, and exhibit wave–particle duality, their behavior featuring properties of both waves and particles. The modern photon concept originated during the first two decades of the 20th century with the work of Albert Einstein, who built upon the research of Max Planck. While trying to explain how matter and electromagnetic radiation could be in thermal equilibrium with one another, Planck proposed that the energy stored within a material object should be regarded as composed of an integer number of discrete, equal-sized parts. To explain the photoelectric effect, Einstein introduced the idea that light itself is made of discrete units of energy. In 1926, Gilbert N. Lewis popularized the term photon for these energy units. Subsequently, many other experiments validated Einstein's approach. In the Standard Model of particle physics, photons and other elementary particles are described as a necessary consequence of physical laws having a certain symmetry at every point in spacetime. The intrinsic properties of particles, such as charge, mass, and spin, are determined by gauge symmetry. The photon concept has led to momentous advances in experimental and theoretical physics, including lasers, Bose–Einstein condensation, quantum field theory, and the probabilistic interpretation of quantum mechanics. It has been applied to photochemistry, high-resolution microscopy, and measurements of molecular distances. Moreover, photons have been studied as elements of quantum computers, and for applications in optical imaging and optical communication such as quantum cryptography.
  • 839
  • 09 Nov 2022
Topic Review
Interference Reflection Microscopy
Interference reflection microscopy (IRM) is an optical microscopy technique that utilizes polarized light to form an image of an object on a glass surface. The intensity of the signal is a measure of proximity of the object to the glass surface. This technique can be used to study events at the cell membrane without the use of a (fluorescent) label in contrast to TIRF microscopy.
  • 833
  • 21 Nov 2022
Biography
Bruno Augenstein
Bruno Wilhelm Augenstein (March 16, 1923 – July 6, 2005) was a Germany -born mathematician and physicist who made important contributions in space technology, ballistic missile research, satellites, antimatter, and many other areas. Augenstein worked in the Aerophysics Laboratory at North American Aviation on diverse projects including weaponization of the V-2 rocket, a ramjet-powered vehic
  • 832
  • 09 Dec 2022
Topic Review
Physical Phenomenology
After a brief digression on the current landscape of theoretical physics and on some open questions pertaining to coherence with experimental results, still to be settled, it is shown that the properties of the deformed Minkowski space lead to a plurality of potential physical phenomena that should occur, provided that the resulting formalisms can be considered as useful models for the description of some aspects of physical reality. 
  • 826
  • 27 Apr 2021
Topic Review
Per- and Polyfluoroalkyl Substances (PFAS) Sorption
Per- and polyfluorinated alkyl substances (PFAS) are an environmentally persistent group of chemicals that can pose an imminent threat to human health through groundwater and surface water contamination. The primary adsorption mechanisms identified in the literature are electrostatic interactions and hydrophobic interactions.
  • 817
  • 18 Jul 2023
Topic Review
Fresnel Imager
A Fresnel imager is a proposed ultra-lightweight design for a space telescope that uses a Fresnel array as primary optics instead of a typical lens. It focuses light with a thin opaque foil sheet punched with specially shaped holes, thus focusing light on a certain point by using the phenomenon of diffraction. Such patterned sheets, called Fresnel zone plates, have long been used for focusing laser beams, but have so far not been used for astronomy. No optical material is involved in the focusing process as in traditional telescopes. Rather, the light collected by the Fresnel array is concentrated on smaller classical optics (e.g. 1/20th of the array size), to form a final image. The long focal lengths of the Fresnel imager (a few kilometers) require operation by two-vessel formation flying in space at the L2 Sun-Earth Lagrangian point. In this two spacecraft formation-flying instrument, one spacecraft holds the focussing element: the Fresnel interferometric array; the other spacecraft holds the field optics, focal instrumentation, and detectors.
  • 812
  • 01 Nov 2022
Topic Review
Heliophysics NASA Science
Heliophysics is an aspect of NASA science that enables understanding the Sun, heliosphere, and planetary environments as a single connected system. In addition to solar processes, this domain of study includes the interaction of solar plasma and solar radiation with Earth, the other planets, and the galaxy. By analyzing the connections between the Sun, solar wind, and planetary space environments, the fundamental physical processes that occur throughout the universe are uncovered. Understanding the connections between the Sun and its planets will allow for predicting the impacts of solar interaction on humans, technological systems, and even the presence of life itself. This is also the stated goal of Science Mission Directorate's Heliophysics Research.
  • 799
  • 25 Oct 2022
Topic Review
Mars Multispectral Imager for Subsurface Studies
Mars Multispectral Imager for Subsurface Studies (MA-MISS) is a miniaturized imaging spectrometer designed to provide imaging and spectra by reflectance in the near-infrared (NIR) wavelength region and determine the mineral composition and stratigraphy. The instrument is part of the science payload on board the European Rosalind Franklin rover, tasked to search for biosignatures, and scheduled to land on Mars in spring 2023. MA-MISS is essentially inside a drill on the Rover, and will take measurements of the sub-surface directly. MA-MISS will help on the search for biosignatures by studying minerals and ices in situ before the collection of samples. The instrument is integrated within the Italian core drill system called DEEDRI, and it will be dedicated to in situ studies of the mineralogy inside the excavated holes in terms of visible and infrared spectral reflectance. The Principal Investigator is Maria Cristina De Sanctis, from the INAF (Istituto di Astrofisica Spaziale e Fisica Cosmica) in Italy.
  • 798
  • 16 Nov 2022
Topic Review
Timeline of Physical Chemistry
The timeline of physical chemistry lists the sequence of physical chemistry theories and discoveries in chronological order.
  • 792
  • 21 Nov 2022
Topic Review
Non-Targeted Effects of Australian and European Synchrotrons
The Australian Synchrotron (AS) and the European Synchrotron Radiation Facility (ESRF) are best configured for a wide range of biomedical research involving animals and future cancer patients. Due to ultra-high dose rates, treatment doses can be delivered within milliseconds, abiding by FLASH radiotherapy principles. In addition, a homogeneous radiation field can be spatially fractionated into a geometric pattern called microbeam radiotherapy (MRT); a coplanar array of thin beams of microscopic dimensions. Both are clinically promising radiotherapy modalities because they trigger a cascade of biological effects that improve tumor control, while increasing normal tissue tolerance compared to conventional radiation. Synchrotrons can deliver high doses to a very small volume with low beam divergence, thus facilitating the study of non-targeted effects of these novel radiation modalities in both in-vitro and in-vivo models. Non-targeted radiation effects studied at the AS and ESRF include monitoring cell–cell communication after partial irradiation of a cell population (radiation-induced bystander effect, RIBE), the response of tissues outside the irradiated field (radiation-induced abscopal effect, RIAE), and the influence of irradiated animals on non-irradiated ones in close proximity (inter-animal RIBE).
  • 786
  • 19 Apr 2022
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