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Topic Review
International Space Station Program
The International Space Station program is tied together by a complex set of legal, political and financial agreements between the fifteen nations involved in the project, governing ownership of the various components, rights to crewing and utilization, and responsibilities for crew rotation and resupply of the International Space Station. These agreements tie together the five space agencies and their respective International Space Station programs and govern how they interact with each other on a daily basis to maintain station operations, from traffic control of spacecraft to and from the station, to utilization of space and crew time. In March 2010, the International Space Station Program Managers from each of the five partner agencies were presented with Aviation Week's Laureate Award in the Space category, and NASA's International Space Station Program was awarded the 2009 Collier Trophy.
  • 629
  • 10 Nov 2022
Topic Review
Lead Halide Perovskites Opto-Electronic Devices
In Lead Halide Perovskites Opto-Electronic Devices, we will discuss the development in the LHP-based functional devices in recent years. After a brief presentation of the LHP's properties, we will focus on the functional devices including lasers, photodetectors, and modulators. Then the fabrication of the LHP-based devices will be presented, which is followed by the summary and outlook.
  • 629
  • 29 Apr 2021
Topic Review
Biological Small-Angle Scattering
Biological small-angle scattering is a small-angle scattering method for structure analysis of biological materials. Small-angle scattering is used to study the structure of a variety of objects such as solutions of biological macromolecules, nanocomposites, alloys, and synthetic polymers. Small-angle X-ray scattering (SAXS) and small-angle neutron scattering (SANS) are the two complementary techniques known jointly as small-angle scattering (SAS). SAS is an analogous method to X-ray and neutron diffraction, wide angle X-ray scattering, as well as to static light scattering. In contrast to other X-ray and neutron scattering methods, SAS yields information on the sizes and shapes of both crystalline and non-crystalline particles. When used to study biological materials, which are very often in aqueous solution, the scattering pattern is orientation averaged. SAS patterns are collected at small angles of a few degrees. SAS is capable of delivering structural information in the resolution range between 1 and 25 nm, and of repeat distances in partially ordered systems of up to 150 nm in size. Ultra small-angle scattering (USAS) can resolve even larger dimensions. The grazing-incidence small-angle scattering (GISAS) is a powerful technique for studying of biological molecule layers on surfaces. In biological applications SAS is used to determine the structure of a particle in terms of average particle size and shape. One can also get information on the surface-to-volume ratio. Typically, the biological macromolecules are dispersed in a liquid. The method is accurate, mostly non-destructive and usually requires only a minimum of sample preparation. However, biological molecules are always susceptible to radiation damage. In comparison to other structure determination methods, such as solution NMR or X-ray crystallography, SAS allows one to overcome some restraints. For example, solution NMR is limited to protein size, whereas SAS can be used for small molecules as well as for large multi-molecular assemblies. Solid-State NMR is still an indispensable tool for determining atomic level information of macromolecules greater than 40 kDa or non-crystalline samples such as amyloid fibrils. Structure determination by X-ray crystallography may take several weeks or even years, whereas SAS measurements take days. SAS can also be coupled to other analytical techniques like size-exclusion chromatography to study heterogeneous samples. However, with SAS it is not possible to measure the positions of the atoms within the molecule.
  • 629
  • 09 Oct 2022
Topic Review
Optical Polarization-Based Measurement for Peptides and Amino Acids
Polarization-based optical measurement methods are very useful in the analysis of the molecular orientations of materials, and, thus, these methods are implemented in numerous material-science studies, including into the characterization of amino acids’ (SAPA)  micro- and nanostructures.
  • 628
  • 21 Mar 2022
Topic Review
Ultrafast Laser in Orthopedic Surgery
The potential of ultrafast lasers (pico- to femtosecond) in orthopedics-related procedures has been studied extensively for clinical adoption. As compared to conventional laser systems with continuous wave or longer wave pulse, ultrafast lasers provide advantages such as higher precision and minimal collateral thermal damages. Translation to surgical applications in the clinic has been restrained by limitations of material removal rate and pulse average power, whereas the use in surface texturing of implants has become more refined to greatly improve bioactivation and osteointegration within bone matrices.
  • 628
  • 07 May 2022
Topic Review
Polarization Lidar
Traditional lidar techniques mainly rely on the backscattering/echo light intensity and spectrum as information sources. In contrast, polarization lidar (P-lidar) expands the dimensions of detection by utilizing the physical property of polarization. By incorporating parameters such as polarization degree, polarization angle, and ellipticity, P-lidar enhances the richness of physical information obtained from target objects, providing advantages for subsequent information analysis.
  • 627
  • 12 Oct 2023
Biography
Charles V. Shank
Charles Vernon (Chuck) Shank (born July 12, 1943) is an American physicist, best known as the director of the Lawrence Berkeley National Laboratory from 1989 to 2004. Charles Vernon (Chuck) Shank was born in Mount Holly, New Jersey, on July 12, 1943.[1][2][3] He entered the University of California, Berkeley, where he earned his Bachelor of Science (B.S.) degree in 1965, his Master of Science
  • 628
  • 29 Dec 2022
Topic Review
Nutrition/Exercise in Upper Gastrointestinal Cancers
Malnutrition and muscle wasting are associated with impaired physical functioning and quality of life in oncology patients. Patients diagnosed with upper gastrointestinal (GI) cancers are considered at high risk of malnutrition and impaired function. Due to continuous improvement in upper GI cancer survival rates, there has been an increased focus on multimodal interventions aimed at minimizing the adverse effects of cancer treatments and enhancing survivors’ quality of life. 
  • 628
  • 28 Sep 2021
Topic Review Video
Black Hole
Black holes are the celestial objects existing at the center of every galaxy. They can currently only be described by their spin, charge, and angular momentum, with other attributes derived from the basic properties. The existence of black holes was first predicted by German physicist and astronomer Karl Schwarzschild in 1916, with the exact solutions to Einstein's field equations of general relativity one year after its publication. Finnish physicist Gunnar Nordström proposed a theory of gravity and electromagnetism with four spatial dimensions in 1914, and later developed into the stationary charged black hole in 1918.
  • 629
  • 15 Oct 2023
Topic Review
Bio-Photonic Cavities
An eco-friendly approach to usual optical cavities, in which an electromagnetic radiation can release energy to matter by interacting with its molecular or atomic structure. Based on bio-inspired and biodegradable meta-surfaces, able to behave as a resonator for light, their optical response can be engineered at will to accomplish a particular optical task.  
  • 627
  • 24 Nov 2021
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