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Topic Review
Osgood-Schlatter Disease
Osgood-Schlatter disease is the most common osteochondritis of the lower limb in sport-practicing children and adolescents. Its manifestation usually coincides with the appearance of the secondary ossification center of the tibia and is linked to the practice of sports with an explosive component. 
  • 1.5K
  • 08 Jun 2022
Topic Review
Thermoporometry and Cryoporometry
Thermoporometry and cryoporometry are methods for measuring porosity and pore-size distributions. A small region of solid melts at a lower temperature than the bulk solid, as given by the Gibbs–Thomson equation. Thus, if a liquid is imbibed into a porous material, and then frozen, the melting temperature will provide information on the pore-size distribution. The detection of the melting can be done by sensing the transient heat flows during phase transitions using differential scanning calorimetry – DSC thermoporometry, measuring the quantity of mobile liquid using nuclear magnetic resonance – NMR cryoporometry (NMRC) or measuring the amplitude of neutron scattering from the imbibed crystalline or liquid phases – ND cryoporometry (NDC). To make a thermoporometry / cryoporometry measurement, a liquid is imbibed into the porous sample, the sample cooled until all the liquid is frozen, and then warmed until all the liquid is again melted. Measurements are made of the phase changes or of the quantity of the liquid that is crystalline / liquid (depending on the measurement technique used). The techniques make use of the Gibbs–Thomson effect: small crystals of a liquid in the pores melt at a lower temperature than the bulk liquid : The melting point depression is inversely proportional to the pore size. The technique is closely related to that of use of gas adsorption to measure pore sizes but uses the Gibbs–Thomson equation rather than the Kelvin equation. They are both particular cases of the Gibbs Equations (Josiah Willard Gibbs): the Kelvin equation is the constant temperature case, and the Gibbs–Thomson equation is the constant pressure case.
  • 1.5K
  • 29 Sep 2022
Topic Review
Thermochemical Cycle
Thermochemical cycles combine solely heat sources (thermo) with chemical reactions to split water into its hydrogen and oxygen components. The term cycle is used because aside of water, hydrogen and oxygen, the chemical compounds used in these processes are continuously recycled. If work is partially used as an input, the resulting thermochemical cycle is defined as a hybrid one.
  • 1.5K
  • 14 Oct 2022
Biography
Carl Eckart
Carl Henry Eckart (May 4, 1902 in St. Louis, Missouri – October 23, 1973 in La Jolla, California ) was an United States physicist, physical oceanographer, geophysicist, and administrator. He co-developed the Wigner–Eckart theorem and is also known for the Eckart conditions in quantum mechanics,[1] and the Eckart–Young theorem in linear algebra.[2] Eckart began college in 1919 at Washing
  • 1.5K
  • 14 Dec 2022
Topic Review
Amperometric Biosensors and Biofuel Cells
Amperometric biosensors and biofuel cells are mostly based on immobilized enzymes or living cells. Among the many oxidoreductases, glucose oxidase (GOx) is used mostly in biosensor design. The same GOx can be well applied for the development of biofuel cells and self-charging capacitors based on the operation of biofuel cells. 
  • 1.5K
  • 24 Aug 2021
Topic Review
History of Wildlife Tracking Technology
The history of wildlife tracking technology involves the evolution of technologies that have been used to monitor, track, and locate many different types of wildlife. Many individuals have an interest in tracking wildlife, including biologists, scientific researchers, and conservationists. Biotelemetry is "the instrumental technique for gaining and transmitting information from a living organism and its environment to a remote observer".
  • 1.5K
  • 10 Oct 2022
Biography
Robert Griffiths
Robert B. Griffiths (February 25, 1937) is an American physicist at Carnegie Mellon University. He is the originator of the consistent histories approach to quantum mechanics, which has since been developed by himself, Roland Omnès, Murray Gell-Mann, and James Hartle. Robert B. Griffiths was born in Etah, Uttar Pradesh in 1937 to Presbyterian missionaries. Griffiths attended Woodstock School
  • 1.5K
  • 29 Dec 2022
Topic Review
Firewall
A black hole firewall is a hypothetical phenomenon where an observer falling into a black hole encounters high-energy quanta at (or near) the event horizon. The "firewall" phenomenon was proposed in 2012 by physicists Ahmed Almheiri, Donald Marolf, Joseph Polchinski, and James Sully as a possible solution to an apparent inconsistency in black hole complementarity. The proposal is sometimes referred to as the AMPS firewall, an acronym for the names of the authors of the 2012 paper. The potential inconsistency pointed out by AMPS had been pointed out earlier by Samir Mathur who used the argument in favour of the fuzzball proposal. The use of a firewall to resolve this inconsistency remains controversial, with physicists divided as to the solution to the paradox.
  • 1.4K
  • 07 Nov 2022
Topic Review
Industrial Applications of Nanotechnology
Nanotechnology is impacting the field of consumer goods, several products that incorporate nanomaterials are already in a variety of items; many of which people do not even realize contain nanoparticles, products with novel functions ranging from easy-to-clean to scratch-resistant. Examples of that car bumpers are made lighter, clothing is more stain repellant, sunscreen is more radiation resistant, synthetic bones are stronger, cell phone screens are lighter weight, glass packaging for drinks leads to a longer shelf-life, and balls for various sports are made more durable. Using nanotech, in the mid-term modern textiles will become "smart", through embedded "wearable electronics", such novel products have also a promising potential especially in the field of cosmetics, and has numerous potential applications in heavy industry. Nanotechnology is predicted to be a main driver of technology and business in this century and holds the promise of higher performance materials, intelligent systems and new production methods with significant impact for all aspects of society.
  • 1.4K
  • 29 Nov 2022
Topic Review
Horror Vacui
In physics, horror vacui, or plenism (/ˈpliːnɪzəm/), commonly stated as "nature abhors a vacuum", is a postulate attributed to Aristotle, who articulated a belief, later criticized by the atomism of Epicurus and Lucretius, that nature contains no vacuums because the denser surrounding material continuum would immediately fill the rarity of an incipient void. He also argued against the void in a more abstract sense (as "separable"), for example, that by definition a void, itself, is nothing, and following Plato, nothing cannot rightly be said to exist. Furthermore, insofar as it would be featureless, it could neither be encountered by the senses, nor could its supposition lend additional explanatory power. Hero of Alexandria challenged the theory in the first century CE, but his attempts to create an artificial vacuum failed. The theory was debated in the context of 17th-century fluid mechanics, by Thomas Hobbes and Robert Boyle, among others, and through the early 18th century by Sir Isaac Newton and Gottfried Leibniz.
  • 1.4K
  • 08 Oct 2022
Topic Review
Perturbative/Non-Perturbative Quantum Field Theory
In this review, we focused on the foundations of quantum field theory, which is still believed to be the most fundamental theory, describing in principle all phenomena observed in atomic and particle physics. Unlike quantum mechanics, however, its foundations are still not cleared up. We attempted to describe how some novel approaches lead to a unified picture, in spite of the fact that several difficult open problems remain.
  • 1.4K
  • 20 Jul 2021
Topic Review
Synchronicity
An article about the term "synchronicity" defined as the occurrence of meaningful coincidences that seem to have no cause.
  • 1.4K
  • 14 Jan 2025
Topic Review
Udwadia–Kalaba Equation
In theoretical physics, the Udwadia–Kalaba equation is a method for deriving the equations of motion of a constrained mechanical system. The equation was first described by Firdaus E. Udwadia and Robert E. Kalaba in 1992. The approach is based on Gauss's principle of least constraint. The Udwadia–Kalaba equation applies to both holonomic constraints and nonholonomic constraints, as long as they are linear with respect to the accelerations. The equation generalizes to constraint forces that do not obey D'Alembert's principle.
  • 1.4K
  • 14 Oct 2022
Biography
Arie Bodek
Arie Bodek (born 1947) is an American experimental particle physicist and the George E. Pake Professor of Physics at the University of Rochester.[1] Bodek was awarded the 2004 American Physical Society W.K.H. Panofsky Prize in Experimental Particle Physics for his "broad, sustained, and insightful contributions to elucidating the structure of the nucleon, using a wide variety of probes, tools,
  • 1.4K
  • 29 Dec 2022
Biography
Uschi Steigenberger
Ursula "Uschi" Steigenberger (25 April 1951 — 12 December 2018) OBE FInstP was a German condensed matter physicist and director of the ISIS neutron source. She was one of the founders of the Institute of Physics Juno Award. Steigenberger was born in Augsburg. She studied physics at the University of Würzburg, where she remained for her graduate studies. She earned a PhD in condensed matter
  • 1.4K
  • 01 Dec 2022
Topic Review
Complex Nonlinear Biophysical Brain Dynamics
The human brain is a complex network whose ensemble time evolution is directed by the cumulative interactions of its cellular components, such as neurons and glia cells. Coupled through chemical neurotransmission and receptor activation, these individuals interact with one another to varying degrees by triggering a variety of cellular activity from internal biological reconfigurations to external interactions with other network agents. Consequently, such local dynamic connections mediating the magnitude and direction of influence cells have on one another are highly nonlinear and facilitate, respectively, nonlinear and potentially chaotic multicellular higher-order collaborations. Thus, as a statistical physical system, the nonlinear culmination of local interactions produces complex global emergent network behaviors, enabling the highly dynamical, adaptive, and efficient response of a macroscopic brain network.
  • 1.4K
  • 07 Jun 2022
Topic Review
Relaxation
In the physical sciences, relaxation usually means the return of a perturbed system into equilibrium. Each relaxation process can be categorized by a relaxation time τ. The simplest theoretical description of relaxation as function of time t is an exponential law exp(-t/τ) (exponential decay).
  • 1.4K
  • 25 Oct 2022
Topic Review
Quantum Measurement
The Special State Theory of Quantum MeasurementL. S. Schulman1   There is only pure unitary time evolution in the special state theory of quantum measurement. In this, it resembles the Many Worlds Interpretation. Nevertheless, there is only one world. This is accomplished by means of “special states” and significant modification the arrow of time. Experimental tests are described, although they have yet to be done.
  • 1.4K
  • 29 Oct 2020
Biography
Daryl Chapin
Daryl Muscott Chapin[1] (21 July 1906 – 19 January 1995) was an American physicist, best known for co-inventing solar cells in 1954 during his work at Bell Labs alongside Calvin S. Fuller and Gerald Pearson. For this, he was inducted into the National Inventors Hall of Fame in 2008. Chapin was born in Ellensburg, Washington (state) on 21 July 1906, although he spent his childhood in Salem,
  • 1.4K
  • 22 Nov 2022
Topic Review
Types of Membrane Transporters in Plants
Membrane transporters are proteins that mediate the entry and exit of substances through the plasma membrane and organellar membranes and are capable of recognizing and binding to specific substances, thereby facilitating substance transport. Membrane transporters are divided into different types, e.g., ion transporters, sugar transporters, amino acid transporters, and aquaporins, based on the substances they transport. These membrane transporters inhibit reactive oxygen species (ROS) generation through ion regulation, sugar and amino acid transport, hormone induction, and other mechanisms. They can also promote enzymatic and nonenzymatic reactions in plants, activate antioxidant enzyme activity, and promote ROS scavenging. Moreover, membrane transporters can transport plant growth regulators, solute proteins, redox potential regulators, and other substances involved in ROS metabolism through corresponding metabolic pathways, ultimately achieving ROS homeostasis in plants.
  • 1.4K
  • 20 Feb 2024
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