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Single-molecule biophysics has become a ground-breaking field that enables scientists to precisely study biological processes at the nanoscale. This review examines the most current developments and uses of single-molecule methods for studying biomolecular interactions, DNA mechanics, protein folding, and cellular dynamics, such as fluorescence microscopy and force spectroscopy. The behavior and functions of individual biomolecules within intricate biological settings are better understood by researchers through the study of individual biomolecules. Additionally, the study of cellular machines, the development of molecular motors, and the creation of synthetic biomolecules have all been made possible by the intriguing applications of single-molecule biophysics in cellular and synthetic biology. The incorporation of single-molecule biophysics into these fields creates new opportunities for comprehending basic biological processes and utilizing biomolecular engineering for a wide range of biotechnology and medical applications. More fundamental secrets of life will be revealed as this subject develops, opening the door for ground-breaking discoveries across a range of scientific and medical fields.

The thermal performance of two-dimensional (2D) field-effect transistors (FET) is investigated frequently by solving the Fourier heat diffusion law and the Boltzmann transport equation (BTE). With the introduction of the new generation of 3D FETs in which their thickness is less than the phonon mean-free-path it is necessary to carefully simulate the thermal performance of such devices. This paper numerically integrates the BTE in common 2D transistors including planar single layer and Silicon-On-Insulator (SOI) transistor, and the new generation of 3D transistors including FinFET and Tri-Gate devices. In order to decrease the directional dependency of results in 3D simulations; the Legendre equal-weight (P_N-EW) quadrature set has been employed. It is found that if similar switching time is assumed for 3D and 2D FETs while the new generation of 3D FETs has less net energy consumption, they have higher hot-spot temperature. The results show continuous heat flux distribution normal to the silicon/oxide interface while the temperature jump is seen at the interface in double layer transistors.

This paper uses the finite volume lattice Boltzmann method (FVLBM) to simulate the transient heat conduction from macro- to nano-scales corresponding to Kn = 0.01–10. This model is used for two dimensional (2D) transient hotspot modeling. The results of the diffusive regime are compared with those of the Fourier law as a model of continuum mechanics and an excellent agreement is found in this regime. After the validation of model for the case of Kn = 0.01, it has been used for high-Knudsen number simulations and a test case with Kn = 10 is studied. By increasing the Knudsen number from 0.01 up to 10, the transition from totally diffusive to totally ballistic behavior has been discussed and the wave-feature of heat transport through the solid material has been investigated.

The aim of this paper is to investigate the dynamical behavior of a Carbon atom under the forces of the two fullerenes in the circular restricted three-body (CR3B) configuration with nanoscale. Here, we assume that the mass of a Carbon atom varies according to the Jeans law, and then with the use of Meshcherskii transformation, we determine the equations of motion and quasi-Jacobian integral. Then by the use of numerical values of the parameters, we investigate the potential surfaces, equilibrium points, regions of motion, Poincaré surfaces of sections, periodic orbits, basins of attraction and stability of the equilibrium points.

The effect of YBCO nanoparticles added into MgB₂ on T_c, J_c, and flux pinning was studied for MgB₂(YBCO)_x with x=0, 5, 10, 15 wt%. Phase analysis shows that none of elements are doped into the MgB₂ lattice in the samples with YBCO addition. For the samples with YBCO addition, the J_c-H characteristics behave poorly in comparison with the pure sample. Our experimental results show that the nanoscale size of addition dosen't comprise the only condition for its effectiveness as pinning centers.

Based on Gurtin–Murdoch surface/interface model and complex potential theory, by constructing a new conformal mapping function, the fracture behavior on n nano-cracks emanating from a n-polygon nano-hole under far-field anti-plane mechanical load, inplane electrical load and magnetic load is studied. The analytical solutions of stress intensity factor, electric displacement intensity factor and magnetic induction intensity factor at the crack tip are given under the boundary conditions of magnetoelectrically semi-permeable. In addition, numerical examples show that when considering the surface effect, the stress field intensity factor, electric displacement intensity factor and magnetic induction intensity factor have obvious size-dependence. The results of this paper show that when the defect size increases to a certain extent, the influence of the surface effect begins to decrease, and finally tends to the results of classical elastic theory.

Derived through liquid phase exfoliation, the irradiation response of nanoscale, exfoliated tin sulfide (SnS) systems are being reported in this work. The SnS nanosheets were exposed to 90MeV ${\text{C}}^{6+}$ ion beams across fluences ranging from $1\times 10^{10}$ to $1\times 10^{13}$ions/cm². With an electronic energy loss ($S_e$) of $\sim$56eV/Å, dominating over the nuclear energy loss ($S_n$), the average crystallite size of the irradiated samples displayed an augment when compared to its pristine counterpart. Exhibiting an orthorhombic crystal structure, structural analyses of both pristine and irradiated samples were conducted via X-ray diffraction (XRD) technique. Raman analysis has manifested some modifications in the SnS nanosystem upon radiation exposure, particularly with higher fluences causing local structural disorder and amorphization of the material. Moreover, morphological changes in the irradiated SnS samples were examined using field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM), with AFM images revealing an increase in the root mean square (RMS) roughness corresponding to ion fluence. Furthermore, swift heavy ion (SHI) irradiation prompted a non-rectifying Ohmic $I\sim V$ characteristics and altered the electrical conductivity of the SnS nanosheets.

Nanoshells composed of close-packed nickel nanoparticles have been fabricated on sillca spheres via strong interaction between the metallic cations and ions of the support. The nickel hollow nanoballs can be self-assembled via magnetic field-assisted route, which is confirmed by the transmission electron microscopy. The magnetic properties of Ni nanoshells are discussed. It is expected that the prepared method can be extended to the synthesis of other hollow metal spheres.

Based on the Gurtin–Murdoch surface/interface model and complex potential theory, by constructing a new conformal mapping, the anti-plane fracture problem of three nano-cracks emanating from a magnetoelectrically permeable triangle nano-hole in magnetoelectroelastic materials with surface effect is studied. The exact solutions of the stress intensity factor, the electric displacement intensity factor, the magnetic induction intensity factor, and the energy release rate are obtained under the boundary conditions of magnetoelectrically permeable and impermeable. The numerical examples show the influence of surface effect on the stress intensity factor, the electric displacement intensity factor, the magnetic induction intensity factor, and the energy release rate under two different boundary conditions. It can be seen that the surface effect leads to the coupling of stress, electric and magnetic field, and with the increase of cavity size, the influence of surface effect begins to decrease until it tends to classical elasticity theory.

Comparative Phase Noise analyses of common-source cross-coupled pair, Colpitts, Hartley and Armstrong differential oscillator circuit topologies, designed in 28 nm bulk CMOS technology in a set of common conditions for operating frequencies in the range from 1 GHz to 100 GHz, are carried out in order to identify their relative performance. The impulse sensitivity function (ISF) is used to carry out qualitative and quantitative analyses of the noise contributions exhibited by each circuit component in each topology, allowing an understanding of their impact on phase noise. The comparative analyses show the existence of five distinct frequency regions in which the four topologies rank unevenly in terms of best phase noise performance. Moreover, the results obtained from the ISF show the impact of flicker noise contribution as the major effect leading to phase noise degradation in nanoscale CMOS LC oscillators.

Crosstalk effects in multilayer graphene nanoribbon (GNR) interconnects for the future nanoscale integrated circuits are investigated with the help of ABCD parameter matrix approach for intermediate- and global-level interconnects at 11nm and 8nm technology nodes. The worst-case crosstalk-induced delay and peak crosstalk noise voltages are derived for both neutral and doped zigzag GNR interconnects and compared to those of conventional copper interconnects. The worst-case crosstalk delays for perfectly specular, doped multilayer GNR interconnects are less than 4% of that of copper interconnects for 1mm long intermediate interconnects and less than 7% of that of copper interconnects for 5mm long global interconnects at 8nm node. As far as the worst-case peak crosstalk noise voltage is concerned, neutral GNR interconnects are slightly better performing than their doped counterparts. But from the perspective of overall noise contribution, doped GNR interconnects outperform neutral ones for all the cases. Finally, our analysis shows that from the signal integrity perspective, perfectly specular, doped multilayer zigzag GNR interconnects are a suitable alternative to copper interconnects for the future-generation integrated circuit technology.

Excessive scaling of complementary metal oxide semiconductor (CMOS) technology is the main reason of large power dissipation in electronic circuits. Very large-scale integration (VLSI) industry has chosen an alternative option known as fin-shaped field effect transistor (FinFET) technology to mitigate the large power dissipation. FinFET is a multi-gate transistor which dissipates less leakage power as compared to CMOS transistors, but it does not completely resolve the problem of power dissipation. So, leakage reduction approaches are always required to mitigate the impact of power dissipation. In this paper, cascaded leakage control transistors (CLCT) leakage reduction technique is proposed using FinFET transistors. CLCT approach is tested for basic static logic circuits like inverter, 2-input NAND and NOR gates and compared with the existing leakage reduction techniques for leakage power dissipation and delay calculations at 16 and 14 nm technology nodes using Cadence tools. CLCT approach shows the effective reduction of leakage power with minimum delay penalty. As the domino logic gates are widely used in large memories and high-speed processors therefore, CLCT approach is further utilized for footless domino logic (FLDL) and compared with the available methods at 14nm technology node. CLCT approach reduces 35.16% power dissipation as compared to the conventional domino OR logic. Temperature and multiple parallel fin variations are estimated for the domino OR logic to check its reliable operation. CLCT approach has high-noise tolerance capability in term of unity noise gain (UNG) for domino OR logic as compared to the other methods.

A comprehensive analysis of the individual plasma characteristics and the physical processes involved in the organization of nanoscale solid-state systems throughout a wide spectrum of elemental composition, structural configuration, and dimensionality is presented here. As a result of these phenomena, it may be possible to localize and regulate matter and energy at the nanoscale and to create self-organized nanosolids with exceptional and unique properties. The introduction of a unified conceptual framework that is based on the regulation of the creation, transport, and self-organization of precursor species is followed by the explanation of a number of plasma-specific nonequilibrium and kinetics-driven phenomena that occur over a wide range of temporal and geographical scales. When the plasma is brought down to dimensions of micrometers and nanometers, new emergent phenomena come into play. Examples include chirality-controlled single-walled carbon nanotubes, semiconducting quantum dots and nanowires, ultra-fine manipulation of graphenes, nanodiamonds, and organic matter, as well as nanoplasma effects and nanoplasmas of various states of matter. Over the last several years, there has been intense research into the use of plasma medicine. Due to the vast range of cancer cell selectivity, treating every form of cancer is still a challenging endeavor for medical professionals. Plasma jets and dielectric barrier discharges are two examples of the many varieties of nonthermal plasma devices that have been developed as a result of research in more sophisticated forms of plasma physics. When nonthermal plasma is brought into contact with biological material, a great number of charged particles and reactive species are produced. The primary components consist of plasma ultra-violets, reactive nitrogen species, and reactive oxygen species. These species may be employed alone or in combination with nanomaterials in a variety of biomedical applications that aim to improve human health. They may also be used in the synthesis of nanomaterials with physiological significance. Several different biomedical applications are described in relation to the synergy that may be achieved between plasma and nanomaterials in this study, along with new developments in plasma-based synthesis of physiologically relevant nanomaterials.

Quantum-dot cellular automata (QCA) is an advanced nanotechnology. It is applied to delineate nanoscale technology-based logic circuits. It can potentially be replaced the complementary metal oxide semiconductor (CMOS) technology. This paper proposes an optimal and single clocked multiplexer (Mux) circuit, which is made with the help of 12 number of QCA cells in QCA nanotechnology. The proposed Mux circuit is designed in such a way that it can be used easily for the design of the demultiplexer (DeMux) and data flip-flop (DFF) circuits. The proposed Mux is easily converted to DeMux by exchanging the input and output terminals only. The effectiveness of the proposed Mux, DeMux, and DFF is examined with the designs that are similar and available in literature using the QCA Designer-E and QCA Pro tools. The design of the proposed Mux is 89.06% fault-tolerant and has decreased the quantum cost by 62.50% as compared to best reported design. Energy measurement plays a key role when designs are operating at nanoscale level. Energy approximation is done with the help of the QCA Pro tool. The proposed designs are more energy efficient compared to the existing works.

Since meshfree particle methods have advantages on simulating the problems involving extremely large deformations, fractures etc., they become attractive options to be used in the hierarchical multiscale modeling to approximate a large number of atoms. We propose a nanoscale meshfree particle method with the implementation of the quasicontinuum technique in this paper. The intrinsic properties of the material associated with each particle will be sought from the atomic level via the Cauchy-Born rule. The studies of a nano beam and a nano plate with a central crack show that such a hierarchical modeling can be beneficial from the advantages of meshfree particle methods.

In this paper, a new enhanced noise analysis for active mixers in nanoscale technologies, based on the variations of the two parameters W/L (transistor size) and f_LO (local oscillator frequency) is presented. In this study, two important sections of an active mixer, the switching pair and the transconductor are considered. It is shown that the noise generated by the switching pair and the transconductor is reduced with the technology scaling from 90 nm to 45 nm. Also, it is shown that the variations of the noise generated by the switching pair due to W/L variations in a wide range of local oscillator frequency and in different technology nodes is less than the variations of the noise generated by the transconductor, which shows the importance of the transconductor in the generation of the total mixer output noise. For extracting the noise relations, the contribution of the gate resistance noise to the gate and drain total current noises is considered, whereas this noise is usually assumed to be an independent source in the literature.

In this paper, a new method for global interconnects optimization in nanoscale VLSI circuits using unequal repeater (buffer) partitioning technique is presented. The optimization is performed with the energy-delay product minimization at 65, 90, and 130 nm technology nodes and various loads, using the genetic algorithm (GA) of MATLAB. The results show more improvements of the total propagation delay with respect to the traditional equal buffer partitioning technique. This improvement is obvious for 90 and 130 nm, and with increasing capacitive load, the improvement will be achieved for 65 nm.

Considering sub-micron potassium titanate whiskers (BX-101), nanoscale potassium titanate whiskers (AX-301), sub-micron potassium titanate whiskers (AX-316) and high strength potassium titanate crystal (AX-319) as functional fillers, heat resistant ablative coated fabrics which have high radiant heat reflectivity were prepared. The effect of the type of functional filler on the thermal protection performance of heat resistant ablative coated fabrics was mainly discussed. Research showed that the microstructure of potassium titanate functional filler had a significant impact on the radiant heat reflectivity and thermal insulation performance of the prepared coated fabric. The coated fabric which took nanoscale potassium titanate whiskers (AX-301) with a minimum diameter and greater length-diameter ratio as functional filler has the highest thermal reflectivity and the best insulation property. Heat ray reflectivity of potassium titanate coated fabrics had positive correlation with their crystallinities. The higher the coated fabric crystallinity was, the greater the heat ray reflectivity. Thermogravimetric analysis results showed that after adding four kinds of potassium titanate fillers, the thermal stability of the prepared coated fabrics was enhanced, and the nanoscale potassium titanate whiskers (AX-301) coated fabrics had the best thermal stability.

A parity generator as a combinational logic circuit in digital circuits can generate the parity bit in the transmitter. It is very applicable in digital networking and communications. Also, rather than diodes and transistors, quantum dots will be used in the next-generation circuits. Quantum-dot Cellular Automata (QCA) offers a new platform where binary data is represented by polarized cells that are defined by the electron configurations. Therefore, a coplanar 4-bit parity generator is suggested in this work. This new arrangement eliminates complicated crossovers and provides complete access to all input and output pins. An XOR gate is used to implement the suggested architecture. Simulation waveforms and performance data confirm the proposed circuits’ functioning and advantages. The suggested four-bit parity generator uses less overhead than its equivalents. We simulated and tested the suggested circuit with the assistance of the QCADesigner 2.0.3 simulator. The QCADesigner software findings demonstrate that the suggested design is simpler and less expensive than earlier designs. Compared to the present best design, the suggested four-bit parity generator reduces cell number and latency by 55.29% and 40%, respectively.

In tissue engineering, surface modification has becomes one of the leading methods to enhance initial cell attachment and subsequent cellular growth, differentiation and tissue formation. This work studied growth and behavior of primary bovine articular chondrocytes on self-assembled multilayer nanofilms composed of: polyelectrolytes [poly(styrene sulfonate) (PSS), poly-L-lysine (PLL), poly-D-lysine (PDL), chondroitin sulfate (CS), poly(ethyleneimine) (PEI), poly(dimethyldiallylammonium chloride) (PDDA), poly(ethylene glycol) amine (PEG - NH₂)] and proteins [bovine serum albumin (BSA), collagen, fibronectin, laminin]. These biomaterials were used to build mono-, bi-, and tri-layer nanofilm architectures. Potential cytotoxic effects were assessed using Live/Dead assay and cell proliferation was quantified using MTT assay. Bright field and fluorescence microscopy were used to analyze chondrocyte morphology. ImageJ software was used to analyze the number, mean area, circularity and Feret's diameter of viable cells. Cumulative results demonstrated that chondrocyte growth; proliferation and functionality were dependent on initial cell density, nanofilm thickness and material composition of nanofilms.