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Biomolecular condensates regulate cellular function by compartmentalizing molecules without a surrounding membrane. Condensate function arises from the specific exclusion or enrichment of molecules. Thus, understanding condensate composition is critical to characterizing condensate function. Whereas principles defining macromolecular composition have been described, understanding of small-molecule composition remains limited. Here we quantified the partitioning of ~1,700 biologically relevant small molecules into condensates composed of different macromolecules. Partitioning varied nearly a million-fold across compounds but was correlated among condensates, indicating that disparate condensates are physically similar. For one system, the enriched compounds did not generally bind macromolecules with high affinity under conditions where condensates do not form, suggesting that partitioning is not governed by site-specific interactions. Correspondingly, a machine learning model accurately predicts partitioning using only computed physicochemical features of the compounds, chiefly those related to solubility and hydrophobicity. These results suggest that a hydrophobic environment emerges upon condensate formation, driving the enrichment and exclusion of small molecules.

The current-induced magnetization precession dynamics provoked by the spin transfer torque (STT) in a spin valve device i.e. tri-layer device (commonly spin torque nano oscillator (STNO)) is investigated numerically by solving the governing Landau–Lifshitz–Gilbert–Slonczewski (LLGS) equation. In this study, we have devised an STNO device made of EuO-based ferromagnetic alloy in free and fixed magnetic layers. The copper acts as a nonmagnetic spacer. Here, we have introduced the current induced Oesterd field (CIOF), which is generated when a spin-polarized current passes through the STNO device. In the device, we have tuned the free layer angle θfrom 30∘to 90∘as an increment of 30∘. For every individual θranging from 30∘to 90∘, the generated Oersted field’s strength can be altered by increasing the STNO device’s diameter. Henceforth, it is apparent that the frequency tunability is achieved in the device for all the values of θ. The frequency and power of the device depend entirely on the material’s saturation magnetization, which inherently reflects the current density and coherence of spin-polarized DC. From the results, it is apparent that for a particular θ, the frequency keeps increasing with the eventual decrease in power when we increase the strength of the Oersted field from 10kA/m to 50kA/m. By doing so, the maximum frequency can be tuned up to 212GHz for θ=90∘with Hoeas 50kA/m. The high frequency emitted by the device acts as a linchpin ingredient, as well as a launch pad element in much of scientific and technological point of view. It paves way for a new route in the areas such as high capacity, high precision, high density as well as the sensing applications.

We present our findings on how orange peel coupling (OPC) between the ferromagnetic layers affects spin transfer torque-assisted magnetization reversal dynamics in CoPt, CoFeB, and EuO pentalayer nanopillar devices. We accomplish this by solving the Landau-Lifshitz-Gilbert-Slonczewski (LLGS) equation (dynamical equation) using the Runge-Kutta fourth-order numerical technique. To begin, we examine the influence of OPC on switching times by simulating the LLGS equation separately for each pentalayer device, both with and without OPC. The magnetization switching times for CoPt, CoFeB, and EuO devices in the absence of OPC are 58 ps, 82 ps, and 154 ps, respectively. When introducing OPC in the pentalayer alloys, we observe a reduction in switching times of 3.5%, 11%, and 40% for CoPt, CoFeB, and EuO devices, respectively. Furthermore, we calculate the current density required to reverse the magnetization of the free layer in CoPt, CoFeB, and EuO pentalayer devices, which is found to be 0.78×1012A/m2, 1.8×1012A/m2, and 4.4×1012A/m2, respectively. In addition, we investigate how the thicknesses of the free and spacer layers, as well as the wavelength and amplitude of interface roughness, affect the magnetization switching time. Understanding the effects of OPC paves the way for the practical implementation of spin transfer torque (STT)-based memory devices.

The middle disordered hydrophobic region of the prion protein plays a critical role in conformational conversion of the protein, with pathogenic as well as protective mutations being localized to this region. In particular, it has been shown that the G127V mutation in this region of the human prion protein (huPrP) is protective against the spread of prion disease, but the mechanism of protection remains unknown. In this study, quantitative analyses of the kinetics of fibril formation by wild-type mouse prion protein (moPrP) and G126V moPrP (equivalent to G127V huPrP) reveal important differences: the critical concentration is higher, the lag phase is longer, and the initial effective rate constant of fibril growth is slower for the mutant variant. The study offers a simple biophysical explanation for why the G127V mutation in huPrP would be protective in humans: the ∼5-fold increase in critical concentration caused by the mutation likely results in the critical concentration (below which fibril formation cannot occur) being higher that the concentration of the protein present in and on cells in vivo.

A numerical investigation is done in a 1-D cascaded magnonic antidot waveguide (CMAWs) to obtain the desired channel width by tuning the band structures of the waveguide. The work is categorized into two cases depending on channel width (CW) in CMAWs: Propagation of SWs in (i) constant CW and (ii) varied CW. Based on that, the waveguide is split into two regions, Region (I): Embedded by the equal sides of antidots (Square) exhibits the two allowed frequencies (AFs) within the range of 80 to 150 GHz and Region (II): Embedded by length lmodulation on alternate antidots, maintains constant CW, and the width wmodulation on alternate antidots varied the CW. In each waveguide the Region (I)and Region (II)are cascaded at the centre of the waveguide. The SW propagation in lmodulation (Constant CW) in Region (II)exhibits three AFs, by opening of the bandgap. The tail like-structure distribution of the exchange field’s on alternate antidots regions, that produces an additional AF and also influences the group velocity vgof respective AFs ranges from 397 to 519 m/s. The tunability of CW is possible by varying the width wof alternate antidots, that generate the demagnetization field asymmetrically in Region (II), and drastically reduce the vgwithin the range of ≈128 to 460 m/s. The proposed work to construct the magnonic waveguides in an adjacent manner steers the SW propagation in different selective frequencies, suitable for multiplexing/demultiplexing with desired CWs.

The current-driven magnetization precession dynamics stimulated by Spin-Transfer Torque (STT) in a trilayer spin-valve device (typically Spin-Torque Nanooscillator (STNO)) is numerically investigated by solving the Landau–Lifshitz–Gilbert–Slonczewski (LLGS) equation. We have devised four STNO devices made of ferromagnetic alloys such as CoPt, CoFeB, Fe85B13Ni2and EuO, which act as free and fixed layers. Here, copper acts as a nonmagnetic spacer for all the devices. In this work, we have introduced the current-induced Oersted field, which is generated when a spin-polarized current passes through the device. The generated Oersted field strength is varied by increasing the diameter of the STNO device. Frequency tunability is achieved in all the four devices, whereas the power of the individual device reduces. The frequency and power of the devices depend entirely on the saturation magnetization of the material, which inherently reflects in the current density and the coherence of the spin-polarized DC. In all devices, the frequency increases, whereas the power decreases by increasing the strength of the Oersted field. Among the four devices, the maximum frequency can be tuned up to 104GHz with 40nm device diameter, which is obtained for EuO material. This opens a promising source and paves a glittering future for the nanoscale spintronic devices.