A review is given on the studies of formation of light clusters and heavier fragments in heavy-ion collisions at incident energies from several tens of MeV/nucleon to several hundred MeV/nucleon, ...focusing on dynamical aspects and on microscopic theoretical descriptions. Existing experimental data already clarify basic characteristics of expanding and fragmenting systems typically in central collisions, where cluster correlations cannot be ignored. Cluster correlations appear almost everywhere in excited low-density nuclear many-body systems and nuclear matter in statistical equilibrium where the properties of a cluster may be influenced by the medium. On the other hand, transport models to solve the time evolution have been developed based on the single-nucleon distribution function. Different types of transport models are reviewed putting emphasis both on theoretical features and practical performances in the description of fragmentation. A key concept to distinguish different models is how to consistently handle single-nucleon motions in the mean field, fluctuation or branching induced by two-nucleon collisions, and localization of nucleons to form fragments and clusters. Some transport codes have been extended to treat light clusters explicitly. Results indicate that cluster correlations can have strong impacts on global collision dynamics and correlations between light clusters should also be taken into account.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A known limitation of time-dependent mean-field approaches is a lack of quantum tunneling for collective motions such as in sub-barrier fusion reactions. As a first step toward a solution, a ...time-dependent model is considered using a superposition of Gaussian wave packets, to describe the relative motion between two colliding nuclei, which may be simplified to a problem for one particle in one dimension. In this article, how the model describes the potential-barrier transmission is investigated by paying attention to the time evolution of the phase space distribution, which in particular reveals that the behavior of the free propagation of the incoming state is not trivial, depending on the number of superposed wave packets. Passage over the barrier can occur due to the high-momentum components in the incoming state corresponding to energies above the barrier height, which is, however, of classical nature and needs to be distinguished from the true quantum tunneling. Although a transmitted wave packet in some case may end up with an energy lower than the barrier, a difficulty is noticed in guaranteeing the energy conservation when the energies of different exit channels, e.g. of transmission and reflection, are individually measured. To overcome these issues for a description of quantum tunneling is still a challenging problem. This article mainly treats the same system with the same model as in the paper Hasegawa, Hagino and Tanimura (2020) 1. However, we reach different conclusions.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Nanomaterial testing standards play a crucial role in the international standardization of nanotechnology within ISO. These standards specify the characteristics of nanomaterials that need to be ...measured, as well as the methods and procedures used for conducting such measurements. This paper presents a methodology for the development of nanomaterial testing standards, which addresses raw nanomaterials and intermediate materials like composites, suspensions, films, and coatings containing raw nanomaterials. The methodology is outlined as a scenario comprising several stages towards the goal, where essential actions to be conducted in standardization are identified and integrated into the standard. Furthermore, this paper highlights the significance of these testing standards as a technical foundation for material specification and certification, with the ultimate aim of facilitating the industrialization of nanomaterials by ensuring consistent quality and enabling reliable performance.
HIV-1 viral particle assembly occurs specifically at the plasma membrane and is driven primarily by the viral polyprotein Gag. Selective association of Gag with the plasma membrane is a key step in ...the viral assembly pathway, which is traditionally attributed to the MA domain. MA regulates specific plasma membrane binding through two primary mechanisms including: (1) specific interaction of the MA highly basic region (HBR) with the plasma membrane phospholipid phosphatidylinositol (4,5) bisphosphate PI(4,5)P
, and (2) tRNA binding to the MA HBR, which prevents Gag association with non-PI(4,5)P
containing membranes. Gag multimerization, driven by both CA-CA inter-protein interactions and NC-RNA binding, also plays an essential role in viral particle assembly, mediating the establishment and growth of the immature Gag lattice on the plasma membrane. In addition to these functions, the multimerization of HIV-1 Gag has also been demonstrated to enhance its membrane binding activity through the MA domain. This review provides an overview of the mechanisms regulating Gag membrane binding through the MA domain and multimerization through the CA and NC domains, and examines how these two functions are intertwined, allowing for multimerization mediated enhancement of Gag membrane binding.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Mercury gauge: An oligodeoxyribonucleotide(ODN)‐based sensor, which carries energy‐donor and ‐acceptor moieties (fluorescein, F, and dabcyl, D, respectively), selectively detects HgII ions in aqueous ...solution. Upon binding HgII ions, the ODN takes on a hairpin structure (see picture); this results in a decrease in the fluorescence emission through enhanced FRET (fluorescence resonance energy transfer) from F to D.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Advances in cell biology and biophysics revealed that cellular membranes consist of multiple microdomains with specific sets of components such as lipid rafts and TEMs (tetraspanin‐enriched ...microdomains). An increasing number of enveloped viruses have been shown to utilize these microdomains during their assembly. Among them, association of HIV‐1 (HIV type 1) and other retroviruses with lipid rafts and TEMs within the PM (plasma membrane) is well documented. In this review, I describe our current knowledge on interrelationships between PM microdomain organization and the HIV‐1 particle assembly process. Microdomain association during virus particle assembly may also modulate subsequent virus spread. Potential roles played by microdomains will be discussed with regard to two post‐assembly events, i.e., inhibition of virus release by a raft‐associated protein BST‐2/tetherin and cell‐to‐cell HIV‐1 transmission at virological synapses.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Influenza A Virus (IAV) is a respiratory virus that causes seasonal outbreaks annually and pandemics occasionally. The main targets of the virus are epithelial cells in the respiratory tract. Like ...many other viruses, IAV employs the host cell's machinery to enter cells, synthesize new genomes and viral proteins, and assemble new virus particles. The cytoskeletal system is a major cellular machinery, which IAV exploits for its entry to and exit from the cell. However, in some cases, the cytoskeleton has a negative impact on efficient IAV growth. In this review, we highlight the role of cytoskeletal elements in cellular processes that are utilized by IAV in the host cell. We further provide an in-depth summary of the current literature on the roles the cytoskeleton plays in regulating specific steps during the assembly of progeny IAV particles.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
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