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Topic Review
OCT Applications in GI Tract
Optical coherence tomography (OCT) is uniquely poised for advanced imaging in the gastrointestinal (GI) tract as it allows real-time, subsurface and wide-field evaluation at near-microscopic resolution, which may improve the current limitations or even obviate the need of superficial random biopsies in the surveillance of early neoplasias in the near future. OCT’s greatest impact so far in the GI tract has been in the study of the tubular esophagus owing to its accessibility, less bends and folds and allowance of balloon employment with optimal contact to aid circumferential imaging. Moreover, given the alarming rise in the incidence of Barrett's esophagus and its progression to adenocarcinoma in the U.S., OCT has helped identify pathological features that may guide future therapy and follow-up strategy. This review will explore the current uses of OCT in the gastrointestinal tract and future directions, particularly with non-endoscopic office-based capsule OCT and the use of artificial intelligence to aid in diagnoses.
  • 646
  • 06 Nov 2020
Topic Review
Perturbation
In astronomy, perturbation is the complex motion of a massive body subjected to forces other than the gravitational attraction of a single other massive body. The other forces can include a third (fourth, fifth, etc.) body, resistance, as from an atmosphere, and the off-center attraction of an oblate or otherwise misshapen body.
  • 645
  • 28 Oct 2022
Topic Review
SpaceIL
SpaceIL is an Israeli nonprofit organization, established in 2011, that was competing in the Google Lunar X Prize (GLXP) to land a spacecraft on the Moon. The contest declared no winner, but SpaceIL still aims to launch the spacecraft in 2019. SpaceIL team was formed as a nonprofit organization wishing to promote scientific and technological education in Israel. Its total budget is estimated at US$70 million, provided mainly by philanthropists and the Israel Space Agency (ISA).
  • 644
  • 24 Oct 2022
Topic Review
Plasma Modeling and Prebiotic Chemistry
The plasma kinetics involves elementary processes by which free electrons ultimately activate weakly reactive molecules, such as carbon dioxide or methane, thereby potentially starting prebiotic reaction chains. These processes include electron–molecule reactions and energy exchanges between molecules. They are basic processes, for example, in the famous Miller-Urey experiment, and become relevant in any prebiotic scenario where the primordial atmosphere is significantly ionized by electrical activity, photoionization or meteor phenomena. The kinetics of plasma displays remarkable complexity due to the non-equilibrium features of the energy distributions involved.
  • 644
  • 18 Mar 2022
Topic Review
Langmuir–Blodgett Graphene-Based Films
The prevalence of photosynthesis, as the major natural solar energy transduction mechanism or biophotovoltaics (BPV), has always intrigued mankind. The development of high performance and durable BPVs is dependent on upgraded anode materials with electrochemically dynamic nanostructures. However, the current challenges in the optimization of anode materials remain significant barriers towards the development of commercially viable technology. Langmuir–Blodgett (LB) film has been substantiated as an efficacious film-forming technique to tackle the above limitations of algal BPVs; however, the aforesaid technology remains vastly untapped in BPVs.
  • 643
  • 08 Mar 2022
Topic Review
Nanocrystalline Magnetic Semiconductors for Spintronics
Сhallenge for spintronics is to find new ways for the control of electronic phenomena and magnetic properties of solids at nanoscale. Some promising aspects are connected with developing new materials. The research highlights the areas devoted to the creation of new functional materials for spintronics based on magnetic semiconductors and demonstrates the technical possibilities of creating various devices, in particular, a maser, a p-n junction with a colossal magnetoresistance, a spin valve, a magnetic lens, modulators, spin wave amplifier, etc. A magnetic semiconductor is a magnetic material that, in terms of specific conductivity, occupies an intermediate position between a conductor and an insulator, and has a band gap comparable to ~kBT. Most known magnetic semiconductors (SC) are either oxides or chalcogenides (sulfides, selenides and tellurides) of 3d transition metals, rare earth 4f metals or a combination. Spintronics (spin electronics) studies spin current transfer (spin-polarized transport) in condensed media, including contact structures, heterostructures, superlattices and multilayers. Much attention is paid to the mechano-physical methods of obtaining of high-density transparent nanoceramics based on magnetic semiconductors. The potential possibility of using nanoceramics as an absorber of solar energy, as well as in modulators of electromagnetic radiation, is also presented. The THz magneto-optics in magnetic semiconductors is shown to be beneficial to the intensively developing fields of spintronics – ultrafast magnetooptics and magnetophotonics in magnetic semiconductors.
  • 642
  • 20 Dec 2022
Topic Review
Masten Space Systems
Masten Space Systems was an aerospace manufacturer startup company in Mojave, California (formerly in Santa Clara, California) that is developing a line of vertical takeoff, vertical landing (VTVL) rockets, initially for uncrewed research sub-orbital spaceflights and eventually intended to support robotic orbital spaceflight launches. In 2020, NASA awarded Masten a contract for a lunar lander mission; NASA is to pay Masten US$75.9 million for Masten to build and launch a lander called XL-1 to take NASA and other customer payloads to the south pole of the Moon. Masten Mission One will be Masten's first space flight; it is scheduled for launch in November 2023. The company filed for Chapter 11 bankruptcy on 28 July 2022. The company would later be purchased by Astrobotic Technology on 11 September 2022.
  • 642
  • 26 Oct 2022
Topic Review
Applications of Droplet Microsystems in Optics and Photonics
The micro- and nano-machining techniques applied to solid materials have yielded remarkable success in the semiconductor industry by integrating complex functionalities into microscale devices, thus spearheading the modern electronics revolution. Extending similar miniaturization strategies to process and assemble soft matter for creating multileveled functional structures over various length scales presents significant scientific and practical potential. Soft matter, including liquid crystals (LC), colloids, polymers, and biological substances, exhibits widespread influence across nature, living organisms, daily life, and industry. The biomimetic properties, responsiveness to stimuli, and efficacy in controlled release and sensing make soft matter extensively applicable in biology and chemistry.
  • 641
  • 18 Mar 2024
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".
  • 641
  • 10 Oct 2022
Topic Review
Sessile Drop Technique
The sessile drop technique is a method used for the characterization of solid surface energies, and in some cases, aspects of liquid surface energies. The main premise of the method is that by placing a droplet of liquid with a known surface energy, the shape of the drop, specifically the contact angle, and the known surface energy of the liquid are the parameters which can be used to calculate the surface energy of the solid sample. The liquid used for such experiments is referred to as the probe liquid, and the use of several different probe liquids is required.
  • 638
  • 29 Nov 2022
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