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Medical and Biological Applications of Low Energy Accelerators
Published in Vlado Valković, Low Energy Particle Accelerator-Based Technologies and Their Applications, 2022
The role of accelerators is best known in their use for surface hardening. When used for surface hardening, the ions of the doping agent material are fired at the target material and only penetrate the material a very short distance, essentially remaining at the surface of the material. Ions are chosen that will complement the atomic structure of the target material, making it stronger. This process is used to create hard surfaces for materials that are used for example in objects like artificial heart valves (Oveissi et al. 2020) and other prosthetic implants.
X-ray Interactions in Matter
Published in Ken Holmes, Marcus Elkington, Phil Harris, Clark's Essential Physics in Imaging for Radiographers, 2021
As you will know from your study of atomic structure, the great majority of the mass is found in the nucleus of the atom with each proton and neutron accounting for approximately one atomic mass unit each.
Radiation Toxicity
Published in Frank A. Barile, Barile’s Clinical Toxicology, 2019
The observation by Becquerel in 1896 of the fogging of photographic plates by uranium salts prompted an intense search for an understanding of the phenomenon of radioactivity. The scientific experimental persistence of the Curies, Schmidt, Debierne, Rutherford, Bohr, and Soddy led to the discoveries of radioactive isotopes and the identification of the types of radiation emitted by these elements. The landmark publication of Bohr’s theory of atomic structure (1913) soon followed.* In 1942, Fermi prepared the schematics for the first nuclear reactor 5 years after Rutherford’s death. Rutherford’s realization of the development of nuclear power until then remained unfulfilled. Since then, constructive research on the atomic nucleus has resulted in the means to harness this energy, not only for the production of electricity and nuclear weapons but also for its application to the medical, pharmaceutical, chemical, and agricultural industries.
Crafting two-dimensional materials for contrast agents, drug, and heat delivery applications through green technologies
Published in Journal of Drug Targeting, 2023
Dwi Setyawan, Tahta Amrillah, Che Azurahanim Che Abdullah, Fasih Bintang Ilhami, Diva Meisya Maulina Dewi, Zuhra Mumtazah, Agustina Oktafiani, Fayza Putri Adila, Moch Falah Hani Putra
Antimonene (AM) is a 2D material that was found in various atomic structures. The most stable atomic structure of AM is α- and β-phases. AM β-phase illustrated in Figure 1(d). AM α-phase has two layers of atoms with a puckered structure [18]. While AM β-phase monolayer consists of a bent hexagonal ring consisting of Antimony (Sb) atoms connected through sp3 bonds [19]. This material is a stable semiconductor with an adjustable band gap, high electrical mobility, structural stability and good mechanical properties [20,21]. In addition, AM has excellent photothermal properties. Drug loading and delivery using AM has a large enough efficiency for heat conversion up to 45.5%. AM also has good optical, catalytic, and electrochemical properties which support them in biomedical purposes such as for drug delivery, imaging and photothermal therapy [22–24].
CDR loop interactions can determine heavy and light chain pairing preferences in bispecific antibodies
Published in mAbs, 2022
Monica L. Fernández-Quintero, Katharina B. Kroell, Lukas J. Grunewald, Anna-Lena M. Fischer, Jakob R. Riccabona, Klaus R. Liedl
While computational tools to fully characterize the Fv region of antibodies are already available, no such tools were published for other immunoglobulin domain interfaces, such as the CH1-CL interface.82 The Orientation of Cylindrical Domains approach88 automatically creates a suitable coordinate system to characterize these interfaces for any user-provided reference structure. Using this tool, a reference coordinate system is created based on user-defined reference structures consisting of an atomic structure and two domain selections over these atoms. To this end, the reference structure for each domain is generated by considering a center axis linking the two centers of mass of the different domains, and the first principal axis P of inertia of each domain corresponding to the lowest eigenvalue of the inertia tensor. Each individual domain is aligned to the world coordinate system by aligning this principal axis to the z unit vector and the center axis as close as possible to the x unit vector, yielding a reference structure for each domain. To map the coordinate system onto a sample structure, the references are aligned to the sample and the alignment transformations are applied to the xyz unit vectors. The transformed z vectors (A1/ B1) and y vectors (A2/B2) as well as the center axis are then used to calculate six orientational measures: Two tilt angles for each vector toward the center axis (AC1, AC2, BC1, BC2), the length of the center axis (dC) and a torsion angle (AB) between the two intersecting planes composed of A1, the center axis and B1.
Magnetic fields and apoptosis: a possible mechanism
Published in Electromagnetic Biology and Medicine, 2022
The spin state plays a pivotal role in all the redox reactions that are at the core of our metabolic machinery. Redox reactions involve the transfer of electrons from one reactant to another. These kinds of reactions are so important that our life depends on them. The synthesis of many complex molecules often requires the oxidation of their precursors, via the use of molecular oxygen. The reason why oxygen is so important in biology is its atomic structure, characterized by the presence of two uncoupled electron spins despite its even atomic number. According to Pauli’s principle, a fundamental principle in quantum physics, oxygen can be considered as an “electron lover,” due to the need of additional electrons to match the coupled spins, in search for stability, thus finally acting as an oxidant. The utilization of molecular oxygen is vital in many biological pathways and the ability of aerobic organisms to harness the power of molecular oxygen as a terminal electron acceptor in their respiratory cycles has revolutionized the evolution of life (Falkowski and Godfrey 2008). The presence of two uncoupled electrons in the oxygen atomic structure makes oxygen a di-radical, since when an electron is uncoupled we are usually dealing with an uncoupled spin or free radical.