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Magnesium (Mg) alloys are attractive biodegradable metal used for medical implant applications. In the present investigation, as-cast and as-rolled Mg–5Zn–0.5Zr alloys were studied for microstructural, mechanical, corrosion behaviour and in vitro biocompatibility. The microstructural changes due to hot rolling strongly influenced the micro-hardness, elastic modulus and corrosion behaviour of the alloy. The micro-hardness of the alloy increased from 66 ± 5 HV in as-cast condition to 84 ± 3 HV after rolling. The corrosion resistance of the alloy decreased after rolling whereas both as-cast and as-rolled alloys showed adequate biocompatibility with mouse osteoblast precursor cell line (MC3T3-E1). In summary, the alloy has potential for customized degradable implant applications and the degradation behaviour depends on the processing route.

Outsourcing of integrated circuit (IC) manufacturing and increasing sophistication of IC reverse engineering techniques have unleashed security threats such as intellectual property (IP) theft and insertion of hardware Trojans. In this article, we propose and implement a run-time reconfigurable camouflage logic technology based on ferroelectric field-effect transistor (FeFET). The technology simultaneously obfuscates design IP from zero-trust foundry and untrusted testing facility and thwarts reverse engineering and counterfeiting threat. We fabricate for the first time an eight FeFET-based circuit block and demonstrate in silico gate-level camouflaging by implementing three Boolean logic functions—NOR, NAND, and XNOR—in the same circuit topology using threshold voltage ( ${V}_{\text {T}}$ ) programming of FeFET. We perform circuit simulations using empirically calibrated models to estimate power, latency, and area overhead. Compared with recent proposal of programmable camouflage logic using hot-carrier injection (HCI), FeFET offers an overhead reduction of $2\times $ , $1.8\times $ , and $2.8\times $ in area, power, and delay, respectively.

Many combinatorial optimization problems can be mapped onto the ground-state search problem of an Ising model. Exploiting the continuous-time dynamics of a network of coupled phase-transition nano-oscillators (PTNOs) allows building an Ising Hamiltonian solver for obtaining optimum or near-optimum solution with a large speed-up over discrete-time iterative digital hardware. Here, we provide insights into the continuous-time dynamics of such a PTNO-based Ising Hamiltonian solver. We highlight the formation of stable attractor states in the phase space of the coupled PTNO network using second-harmonic injection locking (SHIL) that corresponds to the minima of the Ising Hamiltonian. We show that the emergent synchronized dynamics of the PTNO network is maximized near the critical point of oscillator phase bistability beyond which the dynamics is limited by freeze-out effects. Such dynamical freeze-out severely limits the performance of the PTNO-based Ising solver from obtaining the global optimum. We highlight an improvement in the success probability of reaching the ground state by introducing an annealing scheme with linearly increasing SHIL amplitude compared with a constant SHIL. Finally, we estimate the “effective temperature” of the PTNO-based Ising solver by comparing it with the Markov chain Monte Carlo simulations. The PTNO-based Ising solver behaves like a low-temperature Ising spin system, indicating its effectiveness for optimization tasks.

The switching dynamics of a single-domain BiFeO3 nanoscale nanoisland is investigated by studying the dynamics of polarization and Neel vector. We use the Landau–Khalatnikov (LK) equation to describe the evolution of the ferroelectric polarization, and we implement the Landau–Lifshitz–Gilbert (LLG) equations to model the dynamics of spins in two sublattices and the time evolution of the antiferromagnetic order (Neel vector) in a G-type antiferromagnet. Our model can calculate the weak magnetization more accurately compared to previous works on the antiferromagnet using the Neel vector as the order parameter and weak magnetization are often neglected. This work also theoretically demonstrates that the rotation of the magnetic hard-axis, which follows the polarization reversal, can reverse the Neel vector while the weak magnetization remains unchanged. The simulation results are consistent with the ab initio calculations, where the Neel vector rotates during polarization rotation, and also match our calculation of the dynamics of the order parameter using Landau–Ginzburg theory. We also find that the switching time of the Neel vector is a strong function of the polarization switching time and can be as short as 30ps if the polarization can switch faster. However, the Neel vector does not reverse if the polarization switches in less than 30ps.

There is a significant interest in developing the corrosion-resistant magnesium (Mg) alloy as a degradable biomaterial. In this work, the magnesium–zirconium (Zr = 1 wt%)–strontium (Sr = 2 wt%)–cerium (Ce = 0, 0.5 wt%) alloy was developed using the casting process. Effects of Ce addition on alloy microstructure, corrosion behavior, and biocompatibility were systematically investigated. Detailed microstructural analysis indicated that 0.5 wt% Ce addition refined the second phase (Mg17Sr2) in the Mg–2Sr–1Zr alloy. Furthermore, phase analysis of corrosion product showed the formation of stable CeO2 oxide layer on the corroded surface of the Mg alloy. Both the precipitate refinement and stable CeO2 layer formation significantly contributed toward enhanced corrosion resistance of the Mg–Sr–Zr–Ce alloy, as determined by both electrochemical and immersion corrosion in phosphate-buffered saline. Significantly higher osteoblast-like cell (MG-63) proliferation was observed in Ce-containing Mg alloy at both day 1 and day 3. Overall, the results showed that Ce addition could modulate degradation behavior and biocompatibility of the ternary Mg alloy.

Amplified Fragment Length polymorphism (AFLP) was studied involving 48 diverse rice genotypes, comprising of indica, japonica, and Tongil type (indica × japonica) varieties to assess the genetic diversity. Initially 64 primer pair combinations were screened of which 5 were found to be suitable producing clear fragments (35–500 bp). In total 700 amplicons (bands) were produced with an average of 140 bands per primer pair. Maximum (207) from EcoRI AC*/MseI-CAC and minimum (75) amplicons from EcoRI TG*/MseI-CTT primer pairs were observed. Minimum (0.973) and maximum (0.990) PIC values recorded for primer pair EcoRI AC*/MseI-CAC and EcoRI AC*/MseI-CAT, respectively. Pairwise genetic similarity estimates ranged in between 0.6412 and 0.943 with a mean of 0.797. Triguna, an indica high yielding variety (HYV), and a new plant type (NPT) rice, IR 7946-46-1-3-2 having indica x japonica parentage showed minimum genetic similarity coefficient (0.641) with maximum genetic divergence, whereas ADT 41 and Sasyasree, two indica HYVs displayed maximum genetic similarity coefficient—0.953 with lowest genetic distance. All accessions could be clearly identified by using five primer pairs, offers immense scope of AFLP in assessing genetic diversity in rice. The present study also identified prospective varieties for use in selective hybridization and productive progeny selection. Most of the varieties shared distinct clusters based on varietal types, race, parentage and growing area where those are cultivated traditionally albeit with a few exceptions. The dendrogram could demarcate the varieties irrespective of race with unique traits, albeit with exceptions, which warrants further experimentation involving more number of primers in future.

A fundamental problem in parallel and distributed processing is the partial serialization that is imposed due to the need for mutually exclusive access to common resources. In this article, we investigate the problem of optimally scheduling (in terms of makespan) a set of jobs, where each job consists of the same number L of unit-duration tasks, and each task either accesses exclusively one resource from a given set of resources or accesses a fully shareable resource. We develop and establish the optimality of a fast polynomial-time algorithm to find a schedule with the shortest makespan for any number of jobs and for any number of resources for the case of L = 2. In the notation commonly used for job-shop scheduling problems, this result means that the problem J | d ij =1, n j =2| C max is polynomially solvable, adding to the polynomial solutions known for the problems J 2 | n j ≤ 2 | C max and J 2 | d ij = 1 | C max (whereas other closely related versions such as J 2 | n j ≤ 3 | C max , J 2 | d ij ∈ { 1,2} | C max , J 3 | n j ≤ 2 | C max , J 3 | d ij =1 | C max , and J | d ij =1, n j ≤ 3| C max are all known to be NP-complete). For the general case L > 2 (i.e., for the job-shop problem J | d ij =1, n j = L > 2| C max ), we present a competitive heuristic and provide experimental comparisons with other heuristic versions and, when possible, with the ideal integer linear programming formulation.

In this work, we develop Non-Intrusive Reduced Order Models (NIROMs) that combine Proper Orthogonal Decomposition (POD) with a Radial Basis Function (RBF) interpolation method to construct efficient reduced order models for time-dependent problems arising in large scale environmental flow applications. The performance of the POD-RBF NIROM is compared with a traditional nonlinear POD (NPOD) model by evaluating the accuracy and robustness for test problems representative of riverine flows. Different greedy algorithms are studied in order to determine a near-optimal distribution of interpolation points for the RBF approximation. A new power-scaled residual greedy (psr-greedy) algorithm is proposed to address some of the primary drawbacks of the existing greedy approaches. The relative performances of these greedy algorithms are studied with numerical experiments using realistic two-dimensional (2D) shallow water flow applications involving coastal and riverine dynamics.

In this work, we evaluate the role of polarization switching and charge trapping in the operation of ferroelectric FET (FeFET) through combined experimental characterization and comprehensive modeling. We are demonstrating that: 1) the significant charge gap in the quasi-static split-CV (QSCV) and small signal CV is fundamental and not indicative of trapped charge density. This is because the QSCV senses the irreversible polarization switching while the small signal CV mainly probes the reversible domain wall displacement under ac excitation, theoretically yielding different scales of charge response in the two measurements. 2) Trapped charge density during memory write can be inferred from the measured charge release dynamics with the help of a comprehensive FeFET model that incorporates both the polarization switching and the charge trapping and release dynamics.

We report the measurement of collision rate coefficient for collisions between ultracold Cs atoms and low-energy $\mathrm{C}{\mathrm{s}}^{+}$ ions. The experiments are performed in a hybrid trap consisting of a magneto-optical trap (MOT) for Cs atoms and a Paul trap for $\mathrm{C}{\mathrm{s}}^{+}$ ions. The ion-atom collisions impart kinetic energy to the ultracold Cs atoms, resulting in their escape from the shallow MOT and, therefore, in a reduction in the number of Cs atoms in the MOT. By monitoring, using fluorescence measurements, the Cs atom number, and the MOT loading dynamics and then fitting the data to a rate equation model, the ion-atom collision rate is derived. The $\mathrm{Cs}\ensuremath{-}\mathrm{C}{\mathrm{s}}^{+}$ collision rate coefficient $9.3(\ifmmode\pm\else\textpm\fi{}0.4)(\ifmmode\pm\else\textpm\fi{}1.2)(\ifmmode\pm\else\textpm\fi{}3.5)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}14}\phantom{\rule{0.16em}{0ex}}{\mathrm{m}}^{3}\phantom{\rule{0.28em}{0ex}}{\mathrm{s}}^{\ensuremath{-}1}$, measured for an ion distribution with most probable collision energy of 95 meV $(\ensuremath{\approx}{\mathrm{k}}_{\mathrm{B}}\phantom{\rule{4pt}{0ex}}1100\phantom{\rule{4pt}{0ex}}\mathrm{K})$, is in fair agreement with theoretical calculations. As an intermediate step, we also determine the photoionization cross section of Cs $6{P}_{3/2}$ atoms at 473 nm wavelength to be $2.28(\ifmmode\pm\else\textpm\fi{}0.33)\phantom{\rule{4pt}{0ex}}\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}21}\phantom{\rule{0.16em}{0ex}}{\mathrm{m}}^{2}$.

In this work, we developed a comprehensive model for ferroelectric FET (FeFET), which can capture all the essential ferroelectric behaviors. Unlike previous models, which can describe only a subset but not all the reported ferroelectric behaviors, the proposed model can: i) predict device performance with geometry scaling; ii) quantify the device-to-device variation with device scaling; iii) exhibit stochasticity during a single domain switching; and iv) capture the accumulation of domain switching probability with applied pulse trains. This comprehensive model would enable researchers to explore a wide range of FeFET applications and guide device development, optimization and benchmarking.

The paper deals with f ( R ) gravity theory in the background of inhomogeneous FLRW-type space–time model. With proper choice of the inhomogeneous metric function it is possible to have an emergent scenario for the f ( R ) -cosmology. Explicit form of f ( R ) is obtained for power law expansion. It has been shown that the present f ( R ) gravity model is equivalent to some particle creation mechanism in Einstein gravity. Further a complete cosmic evolution from inflation to present late time acceleration is possible with proper continuous choices of the f ( R ) -functions. Finally, in the perspective of thermodynamical analysis a form of f ( R ) has been evaluated using the unified first law.

Ferroelectrics (FEs) are known to decompose into multidomain structures when combined with dielectric (DE) layers. According to current understanding, it is thought that under such conditions, ferroelectric negative capacitance (NC) cannot be stabilized, and the operation of the device would be hysteretic. Here, we report, for the first time, that with a tight control of non-uniformity of the dielectric such that the capacitance matching conditions are nominally achieved, a hysteresis-free negative capacitance can be achieved in a multi-domain FE-DE structure. We capture the inhomogeneous switching in the FE layer by a novel circuit centric modeling framework that incorporates a distribution of domains with different ferroelectric and dielectric parameters. We observe that, in a FE-DE system with no intermediate, metallic layer, as high as ~95% of the ferroelectric domains in can be stabilized in the NC state which allows for the hysteresis free operation. We further show that when an intermediate metallic layer is introduced, the system does not exhibit stabilized NC behavior under any situation. The results could pave the way for understanding the design framework of robust, steep negative capacitance FETs (NCFETs) with multi-domain ferroelectrics.

The paper deals with a non--minimally coupled scalar field in the background of homogeneous but anisotropic Kantowski--Sachs space--time model. The form of the coupling function of the scalar field with gravity and the potential function of the scalar field are not assumed phenomenologically, rather they are evaluated by imposing Noether symmetry to the Lagrangian of the present physical system. The physical system gets considerable mathematical simplification by a suitable transformation of the augmented variables $(a, b, \phi)\rightarrow (u, v, w)$ and by the use of the conserved quantities due to the geometrical symmetry. Finally, cosmological solutions are evaluated and analyzed from the point of view of the present evolution of the Universe., Comment: Accepted in "Annals of Physics"

Porous magnesium has the potential to be used as degradable bone scaffolds. In this study, porous magnesium scaffolds were fabricated through powder metallurgy route utilizing spherical naphthalene particle as porogen. Porogen was removed at 120 °C for 24 h followed by sintering at 550 °C for 2 h in argon atmosphere. Micro-computed tomography (micro CT) results indicated that scaffolds have interconnected porous structure with an equivalent pore diameter of nearly 60 µm. Compressive strength of the scaffolds was found in the range of 24 ± 4.54 MPa to 184 ± 9.9 MPa and decreased with increasing porogen content. In vitro degradation study in phosphate buffered saline (PBS) showed that scaffold degradation behavior was governed by its porosity content. Our results indicate that modulating the porogen content we can tailor the mechanical and degradation behavior of the Mg scaffolds to the application need.

The present work is an attempt to find inter relationship between the cold and warm inflationary scenarios. Here cold inflation is described by a single scalar field (inflaton) and nonequilibrium thermodynamical prescription is imposed. It is found that this quasi-de-Sitter phase of evolution is equivalent to warm inflation. The present work also addresses the question whether the dissipation is Hawking-type or not.

Chemical enhanced oil recovery by surfactantpolymer (SP) flooding has been studied in two space dimensions. A new global pressure for incompressible, immiscible, multicomponent two-phase porous media flow has been derived in the context of SP flooding. This has been used to formulate a system of flow equations that incorporates the effect of capillary pressure and also the effect of polymer and surfactant on viscosity, interfacial tension and relative permeabilities of the two phases. The coupled system of equations for pressure, water saturation, polymer concentration and surfactant concentration has been solved using a new hybrid method in which the elliptic global pressure equation is solved using a discontinuous finite element method and the transport equations for water saturation and concentrations of the components are solved by a Modified Method Of Characteristics (MMOC) in the multicomponent setting. Numerical simulations have been performed to validate the method, both qualitatively and quantitatively, and to evaluate the relative performance of the various flooding schemes for several different heterogeneous reservoirs.

The maximum clique extraction problem finds extensive application in diverse domains like community discovery in social networks, brain connectivity networks, motif discovery, gene expression in bioinformatics, anomaly detection, road networks and expert graphs. Since the problem is NP-hard, known algorithms for finding a maximum clique can be expensive for large real-life graphs. Current heuristics also fail to provide high accuracy and run-time efficiency for dense networks, quite common in the above domains. In this paper, we propose the ALTHEA heuristic to efficiently extract a maximum clique from a dense graph. We show that ALTHEA, based on chi-square statistical significance, is able to dramatically prune the search space for finding a maximum clique, thereby providing run-time efficiency. Further, experimental results on both real and synthetic graph datasets demonstrate that ALTHEA is highly accurate and robust in detecting a maximum clique.

The present work deals with scalar field cosmology in the framework of a quantum gravity modified Einstein-Hilbert Lagrangian with variable $G$ and $\Lambda$. Using Renormalization group, variable $G$ behaves as a minimally coupled filed (not the scalar-tensor theory) and variable $\Lambda$ can be interpreted as a potential function. The point Lagrangian for this model in the background of homogeneous and isotropic flat FLRW space-time model experiences point-like Noether symmetry and equivalent potential function $\Lambda(G)$ is determined. Using a point transformation in the $3D$ augmented space is found that one of the variable become cyclic and as a consequence there is considerable simplification to the physical system. Lastly, the constants of motion can be written in compact form and it is possible to have analytic cosmological solutions in the present context., Comment: 10 pages, 6 figures

We present a system implementing extremely energy-efficient inference on multi-channel biomedical-sensor data. We leverage Ferroelectric FET (FeFET) to perform classification directly on analog sensor signals. We demonstrate: (i) voltage-controlled multi-domain ferroelectric polarization switching to obtain 8 distinct transconductance $(\text{g}_{\text{m}})$ states in a 28nm HKMG FeFET technology [1], (ii) 30x tunable range in $\text{g}_{\text{m}}$ over the bandwidth of interest, (iii) successful implementation of artifact removal, feature extraction and classification for seizure detection from CHB-MIT EEG dataset with 98.46% accuracy and $ . false alarm rate for two patients, (iv) ultra-low energy of 47 fJ/MAC with 1,000x improvement in area compared to alternative mixed-signal MAC.

Biologically plausible mechanism like homeostasis compliments Hebbian learning to allow unsupervised learning in spiking neural networks [1]. In this work, we propose a novel ferroelectric-based quasi-LIF neuron that induces intrinsic homeostasis. We experimentally characterize and perform phase-field simulations to delineate the non-trivial transient polarization relaxation mechanism associated with multi-domain interaction in poly-crystalline ferroelectric, such as Zr doped $\text{HfO}_{2}$ , that underlines the Q-LIF behavior. Network level simulations with the Q-LIF neuron model exhibits a 2.3x reduction in firing rate compared to traditional LIF neuron while maintaining iso-accuracy of 84-85% across varying network sizes. Such an energy-efficient hardware for spiking neuron can enable ultra-low power data processing in energy constrained environments suitable for edge-intelligence.

The present work deals with quantum cosmology for non-minimally coupled scalar field in the background of FLRW space--time model. The Wheeler-DeWitt equation is constructed and symmetry analysis is carried out. The Lie point symmetries are related to the conformal algebra of the minisuperspace while solution of the Wheeler-DeWitt equation is obtained using conserved currents of the Noether symmetries., Accepted for publication in Annals of Physics

Pathogens that are introduced suddenly to natural populations can potentially cause quick changes to the genetics and diversity of the host. In the past three decades, white spot syndrome virus (WSSV) has caused damaging epizootics in Penaeus monodon populations. In this study, we developed WSSV resistance- or susceptibility-linked microsatellite DNA markers, and their effectiveness was validated experimentally. WSSV-resistant marker linked retroelements and genes that may have an important role in WSSV-resistance phenomena were partially identified. Allelic data of 1,694 samples from nine distinct geographic locations in India were revealed that populations from Digha and Kochi were highly dispersed, and also showed higher genetic diversity, higher population diversity, and lower prevalence of disease resistance. A very high level of gene flow was observed within all populations and a very high level of genetic variation was present within populations. Two genetically admixture population clusters were estimated in nature. WSSV-resistance has a significant link with genetic diversity, population cluster and population diversity. Microsatellite marker analysis characterized genetic divergence, diversity and structure among wild populations.

In this work, we investigate the accumulative polarization (P) switching characteristics of ferroelectric (FE) thin films under the influence of sequential electric-field pulses. By developing a dynamic phase-field simulation framework based on time-dependent Landau-Ginzburg model, we analyze P excitation and relaxation characteristics in FE. In particular, we show that the domain-wall instability can cause different spontaneous P-excitation/relaxation behaviors that, in turn, can influence P switching dynamics for different pulse sequences. By assuming a local and global distribution of coercive field among the grains of an FE sample, we model the P-accumulation process in Hf0.4Zr0.6O2 (HZO) and its dependency on applied electric field and excitation/relaxation time. According to our analysis, domain-wall motion along with its instability under certain conditions plays a pivotal role in accumulative P-switching and the corresponding excitation and relaxation characteristics.

In this work, we exploit the spatio-temporal switching dynamics of ferroelectric polarization to realize an energy-efficient, and massively-parallel in-memory computational primitive for at-node sensor data fusion and analytics based on an industrial 28nm HKMG FeFET technology [1]. We demonstrate: (i) the spatio-temporal dynamics of polarization switching in HfO 2 -based ferroelectrics under the stimuli of sub-coercive voltage pulses using experiments and phase-field modeling; (ii) an inherent rectifying conductance accumulation characteristic in FeFET with a large dynamic range of $G_{\max}/G_{\min} > 100$ in the case of 3.0V, 50ns gate pulses; (iii) transition to more abrupt accumulation characteristics due to single/few domain polarization switching in scaled FeFET (34nm L G ); and (iv) successful detection of physiological anomalies from realworld multi-modal sensor data streams.

Paper mill sludge (PMS), a lignocellulosic waste from paper industry, is an ecological burden of environmental concern. Present study explored PMS as substrate for prodigiosin production in solid state fermentation (SSF) and concurrent source of cellulose for Cellulose nanocrystals (CNCs) preparation, using Serratia marcescens NITDPER1. Batch studies revealed maximum pigment production 47 ± 3.2 mg/L after 60 h and ligninolytic potentials via kraft lignin degradation (59 % after 72 h), lignin-mimicking dye decolourization and lignin monomer utilization. In SSF, highest yield was 30.05 ± 1.7 mg/g (24 h) with growth-associated (α = 20.84) and non-growth associated (β = 0.63) parameters determined through Luedeking-Piret model. Lambda max (535 nm), Thin-Layer Chromatography (TLC) (Rf = 0.9), High-Performance Liquid Chromatography (HPLC) (RT = 2.865), Fourier-transform infrared spectra (FT-IR) and Nuclear magnetic resonance (NMR) confirmed it as prodigiosin that exhibited antioxidant potential (IC50 = 47 ± 3.5 μg/mL). After SSF, the delignified (54 %) residual PMS was utilized for preparing CNCs, that displayed particle size 130.8 nm, zeta potential -13.4 mv, polydispersity index 0.404, stability upto 490 °C and revealed desirable properties in Field-emission scanning electron microscopy (FESEM), FT-IR and X-ray diffraction (XRD). Phytotoxicity studies confirmed both prodigiosin and CNCs as non-toxic. This study unveiled biorefinery perspectives for paper industries through production of two commercially important commodities from waste using eco-friendly approach.

A systematic study on the feasibility of an error-free switching of two nanomagnets coupled via their dipolar fields by applying a spin current to one of them is presented. It is demonstrated that the dynamic nature of dipolar interaction between the nanomagnets may cause the magnetization of the second magnet to precess back to its original state despite having crossed the free-axis equatorial plane during the transient phase. This non-reversal is very different than the purely successful or unsuccessful switchings noted in other reversal analyses presented in the literature and, in this paper, is referred to as a dipolar switching glitch. The dynamic dipolar coupling between nanomagnets creates temporary titled precessional trajectories pushing the magnetization of the nanomagnet into high-energy states. Relaxation from these high-energy positions leads to fast, but quasi-random switching behavior. The maximum separation between the magnets for perfect coupling has been quantified as a function of the magnet planar dimensions. It is also shown that the simpler models that do not consider the mutual coupling between the two magnets underestimate the maximum allowed separation between the two magnets and, as such, are too conservative.

The present work deals with evolution of the fractal model of the universe in the background of homogeneous and isotropic FLRW space-time geometry. The cosmic substrum is taken as perfect fluid with barotropic equation of state. A general prescription for the deceleration parameter is determined and it is examined whether the deceleration parameter may have more than one transition during the evolution of the fractal universe for monomial form of the fractal function as a function of the scale factor. Finally, the model has been examined by making comparison with the observed data.

The paper deals with generalized Rastall theory of gravity and its cosmological consequences in the background of homogeneous and isotropic flat FLRW model with perfect fluid as the matter context. The model shows a non singular era (emergent scenario) at the early phase of expansion for a particular choice of the Rastall parameter. Also the model finds to be equivalent to the particle creation mechanism in Einstein gravity in the framework of non-equilibrium thermodynamics. Universal thermodynamics is briefly presented and it is found that the entropy function in Rastall theory is the usual Bekenstein entropy and there is no correction to it. Finally, a complete cosmic history starting from inflation to late time acceleration is presented for suitable choices of the Rastall parameter.

In the Internet of Things environment, it is often the case that a smart device is compatible with a set of gateways. A service composition in such environment may require a set of devices to cooperate to perform a task. These smart devices must be connected with compatible gateways efficiently to maintain the quality of service. In this paper, we consider the problem of allocating devices to compatible gateways while minimizing the maximum traffic at a gateway. We develop a polynomial-time algorithm when all devices required by a service have the same data transmission requirement and establish optimality of the proposed algorithm. We establish that the allocation problem is NP-complete when all participating smart devices have different data transmission requirement. We develop an approximation algorithm to bind smart devices with compatible gateways dynamically when devices have different data transmission requirement. We establish that the maximum traffic assigned to a gateway by the approximation algorithm is at most twice the optimal assignment.

Recently, a new stability criterion has been introduced for general cylindrically symmetric thin-shell wormholes. The present work deals with thin-shell wormholes in the background of static cylindrically symmetric space-time i) with a cosmological constant and ii) with or without a magnetic field in Brans-Dicke gravity and the stability criterion is examined in the perspective of this newly introduced stability analysis. Finally, the stability conditions have been analyzed geometrically.

Recommender systems are widely used to improve sales for online retailers. Due to the large number of users and items, reducing computation time and space requirement for a recommender system has become challenging. In this paper, we propose a simple and effective recommender system based on social network of users. We implemented our proposed recommender system using a hashing technique to take advantage of parallel access to the items rated highly by users. To validate our recommendation method, we performed experiments on a real-world data set. The experimental results demonstrate the effectiveness of the proposed recommender system.

We propose a heterostructure device comprised of magnets and piezoelectrics, which significantly improves the delay and the energy dissipation of an all-spin logic (ASL) device. This paper studies and models the physics of the device, illustrates its operation, and benchmarks its performance using SPICE simulations. We show that the proposed device maintains low-voltage operation, nonreciprocity, nonvolatility, cascadability, and thermal reliability of the original ASL device. Moreover, by utilizing the deterministic switching of a magnet from the saddle point of the energy profile, the device is more efficient in terms of energy and delay and is robust to thermal fluctuations. The results of simulations show that compared to ASL devices, the proposed device achieves $21\times $ shorter delay and $27\times $ lower energy dissipation per bit for a 32-bit arithmetic-logic unit.

As scaling CMOS devices is approaching its fundamental limits, a new direction of research has emerged to study beyond-CMOS spintronic devices that use electronic spin as their state variable, offering new and enhanced functionalities. Due to low operating voltage, non-volatility, and efficient implementation of majority gate, a novel spin-based device, all-spin logic (ASL), has been widely studied for applications including interconnects [1], pattern recognition systems [2], and Boolean gates [3]. However, ASL relies on a non-local spin valve (NLSV) structure with the connection to ground being close to the input magnet to ensure non-reciprocity. Thus, a large fraction of injected spins is shunted to ground without ever reaching the output magnet. In addition, supply clocking is envisioned to reduce energy dissipation [3]. Even then, a 32-bit addition by ASL compared to that by CMOS, requires 5 orders of magnitude more energy. In this paper, we propose a novel device that uses voltage-controlled strain-mediated magnetization switching [4] and spin transfer torque (STT) to perform the first and second 900 of switching, respectively. The STT is created in a conventional spin valve instead of the NLSV structure used in ASL. Hence, the wasteful shunt path to ground is eliminated. Non-reciprocity is ensured through a clocking scheme in which the input and output magnets are oriented along the stable easy axis and the meta-stable saddle point of energy profile, respectively. It has been shown that the deterministic switching of a magnet from a saddle point is more efficient in terms of delay and energy and affected less by thermal noise [5], [6]. The device can be cascaded in a domino logic scheme, Fig. 1 a, by performing the first 900 switching for all cascaded logic gates simultaneously; therefore, the overall delay of a more complicated circuit like a 32-bit adder significantly improves.

Spin waves are propagating disturbances in magnetically ordered materials, analogous to lattice waves in solid systems and are often described from a quasiparticle point of view as magnons. The attractive advantages of Joule-heat-free transmission of information, utilization of the phase of the wave as an additional degree of freedom and lower footprint area compared to conventional charge-based devices have made spin waves or magnon spintronics a promising candidate for beyond-CMOS wave-based computation. However, any practical realization of an all-magnon based computing system must undergo the essential steps of a careful selection of materials and demonstrate robustness with respect to thermal noise or variability. Here, we aim at identifying suitable materials and theoretically demonstrate the possibility of achieving error-free clocked non-volatile spin wave logic device, even in the presence of thermal noise and clock jitter or clock skew., 31 pages including supplementary information

We experimentally demonstrate cooling of trapped ions by collisions with co-trapped, higher mass neutral atoms. It is shown that the lighter $^{39}$K$^{+}$ ions, created by ionizing $^{39}$K atoms in a magneto-optical trap (MOT), when trapped in an ion trap and subsequently allowed to cool by collisions with ultracold, heavier $^{85}$Rb atoms in a MOT, exhibit a longer trap lifetime than without the localized $^{85}$Rb MOT atoms. A similar cooling of trapped $^{85}$Rb$^{+}$ ions by ultracold $^{133}$Cs atoms in a MOT is also demonstrated in a different experimental configuration to validate this mechanism of ion cooling by localized and centered ultracold neutral atoms. Our results suggest that cooling of ions by localized cold atoms holds for any mass ratio, thereby enabling studies on a wider class of atom-ion systems irrespective of their masses., 5 pages (+ 5 pages of Supplementary Material), 4 figures (+ 4 figures in the Supplementary Material)

We report on two-photon photoassociation (PA) spectroscopy of ultracold heteronuclear LiRb molecules. This is used to determine the binding energies of the loosely bound levels of the electronic ground singlet and the lowest triplet states of LiRb. We observe strong two-photon PA lines with power broadened line widths greater than 20 GHz at relatively low laser intensity of 30 W/cm$^{2}$. The implication of this observation on direct atom to molecule conversion using stimulated Raman adiabatic passage (STIRAP) is discussed and the prospect for electronic ground state molecule production is theoretically analyzed., Comment: 8 pages (including supplementary material), 4 figures

The two most widely used ion cooling methods are laser cooling and sympathetic cooling by elastic collisions (ECs). Here we demonstrate another method of cooling ions that is based on resonant charge exchange (RCE) between the trapped ion and the ultracold parent atom. Specifically, trapped Cs$^{+}$ ions are cooled by collisions with co-trapped, ultracold Cs atoms and, separately, by collisions with co-trapped, ultracold Rb atoms. We observe that the cooling of Cs$^{+}$ ions by Cs atoms is more efficient than cooling of Cs$^{+}$ ions by Rb atoms. This signals the presence of a cooling mechanism apart from the elastic ion-atom collision channel for the Cs-Cs$^{+}$ case, which is cooling by RCE. The efficiency of cooling by RCE is experimentally determined and the per-collision cooling is found to be two orders of magnitude higher than cooling by EC. The result provides the experimental basis for future studies on charge transport by electron hopping in atom-ion hybrid systems., Comment: 7 pages, 5 figures

A spin wave majority fork-like structure with feature size of 40 nm, is presented and investigated, through micromagnetic simulations. The structure consists of three merging out-of-plane magnetization spin wave buses and four magneto-electric cells serving as three inputs and an output. The information of the logic signals is encoded in the phase of the transmitted spin waves and subsequently stored as direction of magnetization of the magneto-electric cells upon detection. The minimum dimensions of the structure that produce an operational majority gate are identified. For all input combinations, the detection scheme employed manages to capture the majority phase result of the spin wave interference and ignore all reflection effects induced by the geometry of the structure. (C) 2017 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).

In this article, the convergence of a hybrid numerical method introduced in Daripa and Dutta (J. Comput. Phys., 335:249-282, 2017) has been established. This method integrates a discontinuous finite element method with a modified method of characteristics (MMOC) in combination with finite difference (FD) procedures, and has been successfully applied to solve a coupled system of nonlinear equations that arises in multicomponent two-phase porous media flows. The present convergence analysis is focused on the MMOC-FD procedure for a nonlinear system of transport equations. For this purpose, an analogous single-component system of transport equations has been considered and some key ideas for possible extension to multicomponent systems have been briefly discussed. Error estimates have been obtained and these estimates have also been shown to be consistent with realistic numerical simulations of flows arising in enhanced oil recovery processes., Comment: Updating previous version with accepted preprint

Surface-plasmon-polariton waves propagating at the interface between a metal and a dielectric, hold the key to future high-bandwidth, dense on-chip integrated logic circuits overcoming the diffraction limitation of photonics. While recent advances in plasmonic logic have witnessed the demonstration of basic and universal logic gates, these CMOS oriented digital logic gates cannot fully utilize the expressive power of this novel technology. Here, we aim at unraveling the true potential of plasmonics by exploiting an enhanced native functionality - the majority voter. Contrary to the state-of-the-art plasmonic logic devices, we use the phase of the wave instead of the intensity as the state or computational variable. We propose and demonstrate, via numerical simulations, a comprehensive scheme for building a nanoscale cascadable plasmonic majority logic gate along with a novel referencing scheme that can directly translate the information encoded in the amplitude and phase of the wave into electric field intensity at the output. Our MIM-based 3-input majority gate displays a highly improved overall area of only 0.636 {\mu}m$^2$ for a single-stage compared with previous works on plasmonic logic. The proposed device demonstrates non-Boolean computational capability and can find direct utility in highly parallel real-time signal processing applications like pattern recognition., Comment: Supplementary information included

Genetic transformation of Pusa Basmati 1, a high yielding scented indica rice variety has been successfully achieved using AmSOD gene housed in a binary vector pSFSOD1 under the transcription control of ubiquitin promoter and nos terminator through microprojectile bombardment for increased tolerance towards salinity stress. Initially the protocol was optimized with binary vector pCAMBIA1305.2 harbouring GUS Plus™ reporter gene involving embryogenic calli developed from mature embryos of three rice varieties viz., Pusa Basmati 1, Taraori Basmati and one new plant type-super rice variety- IR70485–15–3-2 using PDS He 2000. The reporter gene showed significant GUS expression, which indicates maximum transformation efficiency at transient level under optimized parameters such as helium pressure-1100 psi, internal vacuum pressure-28″, flight distance-9 cm, microcarrier-1 μM diameter, particle volume-15 μl and microcarrier launch assembly at 6 cm for efficient bombardment of the embryogenic calli. The bombarded calli were transferred to MS medium supplemented with mannitol (0.2 M) and sorbitol (0.2 M) for 4 h, found to be most appropriate osmoticum in bombardment shock recovery and their proliferation. This best optimized protocol was used to dispense AmSOD gene for development of transgenic lines of the most in vitro culture responsive variety Pusa Basmati 1 to impart tolerance to salinity. Putative transgenic plants were developed from the bombarded calli, which were acclimatized, hardened and grown to maturity and analyzed by using molecular, physiological and biochemical assays to determine the introgression of the transgene into the variety. Further, inheritance study showed typical Mendelian ratio for monogenic dominant transgene in the segregating T2 generation. Among progenies tested, PBT 3–2, PBT 6–4 and PBT 8–9 were found to be appreciably tolerant to salinity stress with high yield at different growth stages, which prospects amply for more production and profitability to attain farm prosperity by large-scale cultivation of transgenic Pusa Basmati 1 on saline soils.

In this present work, bioactive glass (BG) reinforced magnesium (Mg) Mg/BG composites were prepared using hot press sintering and the effects of BG content on composite hardness, degradation behaviour and cytocompatibility were studied. Simultaneous increase in temperature and applied pressure in hot press sintering resulted in a unique Mg-BG microstructure where BG partially coated Mg particles. The result was an 6.8 times increase in corrosion resistance of Mg-10 wt% BG compared to pure Mg. The high corrosion resistance of Mg-10 wt%BG had also reduced pH rise of the degradation media and hydrogen evolution, a significant concern for Mg based degradable biomaterials. Degradation behaviour of Mg-BG composites were also studied using micro-CT (µ-CT) which showed lowest porosity increase for Mg-10BG after immersion in PBS for 168 h. In vitro cytocompatibility studies were performed, by extract assay method, using MG-63 cells. The Live/Dead imaging and alamar blue assay indicated that Mg-10BG composites had higher cell viability and proliferation compared to other composites. The present result indicates that in situ BG coating, as prepared by hot press sintering, is an efficient way to increase corrosion resistance and cytocompatibility of Mg based biomaterials.

The direct photodissociation of trapped ${^{85}\mathrm{Rb}}_{2}^{+}$ (rubidium) molecular ions by the cooling light for the $^{85}\mathrm{Rb}$ magneto-optical trap (MOT) is studied, both experimentally and theoretically. Vibrationally excited ${\mathrm{Rb}}_{2}^{+}$ ions are created by photoionization of ${\mathrm{Rb}}_{2}$ molecules formed photoassociatively in the Rb MOT and are trapped in a modified spherical Paul trap. The decay rate of the trapped ${\mathrm{Rb}}_{2}^{+}$ ion signal in the presence of the MOT cooling light is measured and agreement with our calculated rates for molecular ion photodissociation is observed. The photodissociation mechanism due to the MOT light is expected to be active and therefore universal for all homonuclear diatomic alkali metal molecular ions.

We present a technique, based on atoms coupled to an optical cavity, for non-destructive detection of trapped ions. We demonstrate the vacuum-Rabi splitting (VRS), arising due to the collective strong coupling of ultracold Rb atoms to a cavity, to change in presence of trapped Rb+ ions. The Rb+ ions are optically dark and the Rb atoms are prepared in a dark magneto-optical trap (MOT). The VRS is measured on an optically open transition of the initially dark Rb atoms. The measurement itself is fast, non-destructive and has sufficient fidelity to permit the measurement of atomic-state selective ion-atom collision rate. This demonstration illustrates a method based on atom-cavity coupling to measure two particle interactions generically and non-destructively., 6 pages, 3 figures

We propose a comprehensive scheme for building spintronics transducers for back and forth signal conversion between spin and charge domains in addition to the associated CMOS peripheral circuitry for spin wave device (SWD) circuits. We perform systematic analysis of the impact of the transducers on the performance of SWD in terms of energy and area overhead. Performance evaluation of SWD compared with 7nm FinFET CMOS technology at the circuit level, yields a 3× smaller area and an order of magnitude lower energy-delay product (EDP) for large complex circuits with low overhead. Overall, SWD outperforms CMOS with increasing ratio of (logic size/overhead).

The present work deals with a quintom model of dark energy in the framework of a spatially flat isotropic and homogeneous Friedmann-Lemaitre-Robertson-Walker (FLRW) universe. At first, Lie point symmetry is imposed to the system and the unknown coupled potential of the model is determined. Then Noether symmetry, which is also a point like symmetry of the Lagrangian, is imposed on the physical system and the potential takes a general form. It is shown that the Lie algebra of Noether symmetry is a sub-algebra of the corresponding Lie algebra of the Lie symmetry. Finally, a point transformation in the three dimensional augmented space is performed suitably so that one of the variables become cyclic and as a result there is considerable simplification to the physical system. Hence conserved quantities (i.e, constants of motion) are expressed in a compact form and cosmological solutions are evaluated and analyzed in the present context., 14 pages, 6 figures, accepted in IJMPD

Scalar field dark energy cosmology has been investigated in the present paper in the frame work of Einstein gravity. In the context of Friedmann–Lemaitre–Robertson–Walker space time minimally coupled scalar field with self interacting potential and non-interacting perfect fluid with barotropic equation of state (dark matter) is chosen as the matter context. By imposing Noether symmetry on the Lagrangian of the system the symmetry vector is obtained and the self interacting potential for the scalar field is determined. Then we choose a point transformation $$(a, \phi )\rightarrow (u, v)$$ such that one of the transformation variable (say u) is cyclic for the Lagrangian. Subsequently, using conserved charge (corresponding to the cyclic co-ordinate) and the constant of motion, solutions are obtained. Finally, the cosmological implication of the solutions in the perspective of recent observation has been examined.

The present work is an attempt for emergent universe scenario with modified Chaplygin gas. The universe is chosen as spatially flat FRW space-time with modified Chaplygin gas as the only cosmic substratum. It is found that emergent scenario is possible for some specific (unrealistic) choice of the parameters in the equation of state for modified Chaplygin gas., Comment: 7 pages, 3 figures

This paper is aimed to study the group invariant solutions of the evolution equations in Brans–Dicke cosmology. In this context, we have considered the flat homogeneous Brans–Dicke (BD) scalar field in the background of flat homogeneous and isotropic Friedmann–Lemaître–Robertson–Walker (FLRW) cosmological model and have used Lie and Noether symmetry on the augmented system. From Lie symmetry we have determined the unknown potential for two different values of the equation of state parameter w. Then assuming that the Lagrangian admits a Noether symmetry, an analytic solution of the system is obtained in both old and new coordinate systems.