The liquid−liquid phase separation phase separation phenomenon has been described for some biopolymers and has been studied in sufficient detail for a few proteins with intrinsically disordered ...regions. One example of such proteins is the nucleocapsid (N) protein of the severe acute respiratory syndrome coronavirus 2. In this review, we have analyzed available data on N-protein separation in the presence of viral RNA. Particular attention has been paid to transient contacts within the condensates and the N-protein/RNA fragments that form these contacts. The modern concepts of the role of the condensates in the SARS-CoV-2 life cycle and their influence on the host-protective machinery have been summarized. Finally, comments on the possibility of regulating the viral condensates using synthetic or natural small molecules (phase separation modulators), which can provide a new option in the design of antiviral agents, are given.
The vast majority of QED results are obtained in relatively weak fields and so in the framework of perturbation theory. However, forthcoming laser facilities providing extremely high fields can be ...used to enter not-yet-studied regimes. Here, a scheme is proposed that might be used to reach a supercritical regime of radiation reaction or even the fully non-perturbative regime of quantum electrodynamics. The scheme considers the collision of a 100 GeV-class electron beam with a counterpropagating ultraintense electromagnetic pulse. To reach these supercritical regimes, it is unavoidable to use a pulse with ultrashort duration. Using two-dimensional particle-in-cell simulations, it is therefore shown how one can convert a next-generation optical laser to an ultraintense (I ≈ 2.9 × 10
Wcm
) attosecond (duration ≈ 150 as) pulse. It is shown that if the perturbation theory persists in extreme fields, the spectrum of secondary particles can be found semi-analytically. In contrast, a comparison with experimental data may allow differentiating the contribution of high-order radiative corrections if the perturbation theory breaks.
This paper addresses some thermodynamic aspects of adsorptive heat transformation (AHT) driven by ultralow-temperature (ULT) heat. This non-payable heat is available in abundance from various natural ...thermal sources and as heat wastes from industry, transport and power engineering. The link between the temperature thrush that drives an AHT cycle and the obtained temperature lift is analyzed using the Trouton rule.
It is shown that even if only ULT heat with T ≤ 50 °C is available, it can effectively drive adsorptive cooling cycles and obtain an output temperature sufficient for air-conditioning, ice-making, and freezing. Moreover, heat amplification cycles can be driven by ULT heat with a temperature lower than 20 °C. The Dubinin adsorption potential ΔF is proposed as a quantitative measure of the adsorbent affinity, and the quantitative relationship between the temperature thrush and this potential is found for water as an adsorptive. This link can greatly help in choosing adsorbents optimal for the given AHT conditions.
The photometric characteristics in the midinfrared range of compact galaxies with ionizing radiation leakage (LyC galaxies) are studied to find relationships that would enable the quantitative ...assessment of the ionizing radiation that goes beyond the galaxy. In particular, the relationships between the color characteristics of galaxies according to data from the WISE space telescope and radiation fraction
f
esc
(LyC) in the Lyman continuum and radiation fraction
f
esc
(Ly
α
) in the Ly
α
line, which go beyond the galaxy, are investigated. The dependences of
f
esc
(LyC) and
f
esc
(Ly
α
) on color index
W
1–
W
4 are established from the WISE space telescope data, where
W
1 and
W
4 are apparent stellar magnitudes at wavelengths of 3.4 and 22 μm, respectively. This makes color index
W
1–
W
4 a useful indicator for quantifying
f
esc
(LyC) and
f
esc
(Ly
α
) in addition to the previously established some characteristics of LyC galaxies in the optical and ultraviolet ranges. Thus, the radiation of galaxies in the midinfrared range can be used to search for candidates for leaking LyC galaxies with the purpose of their further observations.
The wearable electronic technique is increasingly becoming an effective approach to overcoming the communication obstacles between signers and non-signers. However, the efficacy of conducting ...hydrogels currently proposed as flexible sensor devices is hindered by their poor processability and matrix mismatch, which frequently results in adhesion failure at the combined interfaces and deterioration of mechanical and electrochemical performance. Herein, we propose a hydrogel composed of a rigid matrix in which the hydrophobic and aggregated polyaniline was homogeneously embedded, while quaternate-functionalized nucleobase moieties endowed the flexible network with adhesiveness. Accordingly, the resulting hydrogel with chitosan-graft-polyaniline (chi-g-PANI) copolymers exhibited a promising conductivity (4.8 S·m–1) because of the uniformly dispersed polyaniline components and a high strain strength (0.84 MPa) because of the chain entanglement of chitosan after soaking. In addition, the modified adenine molecules not only realized synchronization in improving the stretchability (up to 1303%) and exhibiting a skin-like elastic modulus (≈184 kPa), but also provided a durable interfacial contact with various materials. The hydrogel was further fabricated into a strain-monitoring sensor for information encryption and sign language transmission based on its sensing stability and strain sensitivity of up to 2.77. The developed wearable sign language interpreting system provides an innovative strategy to assist auditory or speech-impaired people in communicating with non-signers using visual–gestural patterns including body movements and facial expressions.
The charge transport on the electrically charged surface of polytetrafluoroethylene (PTFE) films in the presence of the adsorption of an electrically conductive phase has been studied. The ...attenuation of the rate of displacement of the potential drop over the film surface, which limits the area of its expansion, has been found. An estimate has been made for the critical index of the correlation length of a percolation cluster that forms on an electrified PTFE surface at high humidity. It has been experimentally established that the leak of charge from an electrically charged surface is determined by percolation processes.
The sequence of solar processes leading to positive feedback between the plasma motion and heating, electron acceleration, and, eventually, the formation of coronal mass ejections and shock waves, as ...well as the acceleration of protons was studied. To this end, we analyze the solar events associated with three impulsive flares: M2.9 on July 6, 2012; X2.2 and X9.3 on September 6, 2017; and one gradual M3.7 flare on March 7, 2011. Electrons have been accelerated to relativistic energies in all four flares; however, the latter two flares were accompanied by coronal mass ejections, shock waves, and acceleration of protons with energies over 300 MeV. Two differences have been found for flares without coronal mass ejections: (1) altitude limitations that are characteristic of the radio emission of 1415 MHz (the upper chromosphere) and (2) the maximum of the emission measure in them lagged behind the temperature maximum by less than 2 min. If the flare and coronal mass ejections are assumed to take energy from the same reservoir, the delay time can be considered to be the characteristic time of the acceleration of coronal mass ejections—an additional energy outflow. Theoretical estimates of the maximum acceleration of coronal mass ejections and its minimum and maximum velocities yield the possible scatter in the acceleration time of coronal mass ejections. Comparison of estimates and observations shows that the required duration of acceleration for interplanetary coronal mass ejections was achieved in the M3.7 event on March 7, 2011, and the X9.3 event on September 6, 2017.
Cellulose can replace single-use petrochemical packaging; however, its lack of freshwater durability restricts its applicability. This study used a wet pulverization process to prepare mechanically ...fibrillated cellulose nanofibers (MCNFs). They were followed by sodium periodate oxidation to prepare oxidized cellulose nanofibers (OMCNFs). The MCNFs and OMCNFs were converted into films through solvent casting. The OMCNF film with an aldehyde concentration of 176 µmol/g had a wet tensile strength of ~ 20 MPa, which was significantly higher than that of the MCNF film (~ 2 MPa). In addition, the water durability of the OMCNF film could be further increased to ~ 35 MPa by adding hydroxypropyl starch (HPS). Moreover, starch addition enhanced the degradability of the OMCNF/HPS film in marine conditions. Thus, the OMCNF/HPS film had adequate freshwater durability and marine degradability and has the potential to serve as a next-generation packaging material.
Graphical abstract
Starch is the most abundant biomass and potential replacement of single-use packaging; however, the lack of water durability and wet strength restrict the applicability of starches. ...Hemiacetal/acetals cross-linked starch film have water stability, however, the film possess poor wet strength owing to lack of crystallinity. In this study, we prepared TEMPO-oxidized cellulose nanofiber (TCNF)/starch composite films by mixing different-storage-duration native tapioca starch (NTS), hydroxypropyl starch (HPS), and di-aldehyde starch (Di-aldS) with TCNF. We demonstrate that the films prepared with the stored starch pastes exhibit improved mechanical properties and wet strength owing to the synergistic effect of enhanced crystallinity and hemiacetal crosslinking. However, long-term storage of the starch pastes negatively affected their properties. Thus, improving the film properties by optimizing the starch paste storage time is an environmentally friendly and energy-conserving method. Moreover, our experimental results suggest that TCNF/HPS films prepared with the HPS paste stored for three days (~22 °C, ~25% RH) can be a potential alternative to single-use packaging films.
Display omitted
•Effect of starch pastes storage time on wet strength of TCNF/starch films.•Synergistic effect of hemiacetal crosslinking and crystallinity enhanced water durability of the film.•TCNF/HPS film prepared with 3 days stored HPS paste is quite suitable for application.
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