Text Encryption Using Pell Sequence and Elliptic Curves with Provable Security

The demand for data security schemes has increased with the significant advancement in the field of computation and communication networks. We propose a novel three-step text encryption scheme that has provable security against computation attacks such as key attack and statistical attack. The proposed scheme is based on the Pell sequence and elliptic curves, where at the first step the plain text is diffused to get a meaningless plain text by applying a cyclic shift on the symbol set. In the second step, we hide the elements of the diffused plain text from the attackers. For this purpose, we use the Pell sequence, a weight function, and a binary sequence to encode each element of the diffused plain text into real numbers. The encoded diffused plain text is then confused by generating permutations over elliptic curves in the third step. We show that the proposed scheme has provable security against key sensitivity attack and statistical attacks. Furthermore, the proposed scheme is secure against key spacing attack, ciphertext only attack, and known-plaintext attack. Compared to some of the existing text encryption schemes, the proposed scheme is highly secure against modern cryptanalysis.     

Predicting single-neuron activity in locally connected networks

The characterization of coordinated activity in neuronal populations has received renewed interest in the light of advancing experimental techniques that allow recordings from multiple units simultaneously. Across both in vitro and in vivo preparations, nearby neurons show coordinated responses when spontaneously active and when subject to external stimuli. Recent work (Truccolo, Hochberg, & Donoghue, 2010 ) has connected these coordinated responses to behavior, showing that small ensembles of neurons in arm-related areas of sensorimotor cortex can reliably predict single-neuron spikes in behaving monkeys and humans. We investigate this phenomenon using an analogous point process model, showing that in the case of a computational model of cortex responding to random background inputs, one is similarly able to predict the future state of a single neuron by considering its own spiking history, together with the spiking histories of randomly sampled ensembles of nearby neurons. This model exhibits realistic cortical architecture and displays bursting episodes in the two distinct connectivity schemes studied. We conjecture that the baseline predictability we find in these instances is characteristic of locally connected networks more broadly considered.     

An efficient numerical technique based on the extended cubic B-spline functions for solving time fractional Black–Scholes model

Financial theory could introduce a fractional differential equation (FDE) that presents new theoretical research concepts, methods and practical implementations. Due to the memory factor of fractional derivatives, physical pathways with storage and inherited properties can be best represented by FDEs. For that purpose, reliable and effective techniques are required for solving FDEs. Our objective is to generalize the collocation method for solving time fractional Black–Scholes European option pricing model using the extended cubic B-spline. The key feature of the strategy is that it turns these type of problems into a system of algebraic equations which can be appropriate for computer programming. This is not only streamlines the problems but speed up the computations as well. The Fourier stability and convergence analysis of the scheme are examined. A proposed numerical scheme having second-order accuracy via spatial direction is also constructed. The numerical and graphical results indicate that the suggested approach for the European option prices agree well with the analytical solutions.

     

Development of a probiotic delivery system from agrowastes, soy protein isolate, and microbial transglutaminase

Abstract: Probiotic delivery system was developed via the use of microbial transglutaminase (MTG) cross‐linked soy protein isolate (SPI) incorporated with agrowastes such as banana peel (BE), banana pulp (BU), and pomelo rind (PR). Inoculums of Lactobacillus bulgaricus FTDC 1511 were added to the cross‐linked protein matrix. The incorporation of agrowastes had significantly (P < 0.05) reduced the strength, pH value, and the lightness of the SPI gel carriers, while sodium dodecyl sulfate‐polyacrylamide gel electrophoresis profiles revealed that the occurring cross‐links within the SPI gel carriers were attributed to the addition of MTG. Scanning electron microscope micrographs illustrated that SPI carriers containing agrowastes have exhibited a less‐dense protein matrix. All the SPI carriers possessed maximum swelling ratio at 4 to 4.5 within 15 min in simulated gastric fluid (SGF), whereas the maximum swelling ratios of SPI/BE, SPI/BU, and SPI/PR were higher compared to that of control in simulated intestinal fluid (SIF). Additionally, SPI carriers in SGF medium did not show degradation of structure, whereas a major collapse of network was observed in SIF medium, indicating controlled‐release in the intestines. The addition of agrowastes into SPI carriers led to a significantly (P < 0.0001) lower release of L. bulgaricus FTDC 1511 in SGF medium and a higher release in SIF medium, compared to that of the control. SPI carriers containing agrowastes may be useful transports for living probiotic cells through the stomach prior to delivery in the lower intestines. Practical Application: Agrowastes could be utilized as a new probiotic carrier for enhanced gastrointestinal transit and during storage. This also reduces the amount of agrowastes accumulated.     

Evaluation of microbial transglutaminase and ribose cross-linked soy protein isolate-based microcapsules containing fish oil

Soy protein isolate (SPI)-based microcapsules containing fish oil were prepared using a modified coacervation method followed by cross-linking treatments. The procedure yielded 95–98% microcapsules containing 0.5–0.6 g fish oil/g capsule with a volume mean diameter ranged from ~ 260 to ~ 280 μm. Four types of microcapsules produced were SPI with sucrose (MC-C/S), SPI with ribose (MC-C/R), SPI with sucrose and microbial transglutaminase (MC-MTG/S) and SPI with ribose and MTGase (MC-MTG/R). Protein cross-linking due to ε-(γ-glutamyl)lysine bonds and “Maillard cross-linking” were evidenced in the SDS-PAGE profiles of MC-C/R, MC-MTG/S and MC-MTG/R. Even though the microcapsules prepared with cross-linking treatments had significantly (P < 0.05) lower protein solubility as compared to that of the control, the results of fish oil release in pepsin solution at 37 °C indicated that the core release of all microcapsules prepared with ribose (MC-C/R and MC-MTG/R) was significantly (P < 0.05) lower than other microcapsules. During storage, microcapsules prepared with ribose had longer shelf life as compared to other microcapsules. This may be due to the release of antioxidative Maillard reaction products during heating and storage and a slower rate of gas permeability through the capsules.

Industrial relevance

The use of protein-based wall materials in the food industry for sensitive ingredients is limited because proteins are generally unstable with heating and damaged by organic solvents and the cross-linking agent is usually harmful. Therefore a novel method of combining two familiar cross-linking agents such as the microbial transglutaminase and ribose can convert SPI microcapsules into a stable form. The application of SPI in industry would be increased.     

The Influence of Conceptual Flow Simulation Model Parameters on Model Solution

This article investigates the influence of conceptual flow simulation model parameters (i.e coefficients and constants that need to be estimated in calibration) on model solution (surface runoff) to understand the characteristics of the model. A new conceptual watershed yield model (WYM) was employed. There are four physical parameters, two fitting coefficients and two initial estimates of the surface water and groundwater storagesthat control the functioning of the model. The conceptual model was applied on Ling River near Kahuta and detailed sensitivity analysis was performed to explore the most sensitive model parameters. The most sensitive model parameters worked out were C _g (a fitting coefficient, which reflects the rate at whichgroundwater runoff occurs), w _r (watershed retention is the initial rainfall losses before runoff begins), p _gr (inputparameter that reflects the discharge capacity of the groundwateraquifer). The model parameters like i _c (infiltration coefficient), g _wsm (input parameter that depends on the subsurface storage available in the watershed) and e _p (input parameter) have negligible effect on model solution. It was observed that w _r (watershed retention) is the only surface runoff controlling parameter and p _gr and C _g are the groundwater runoff controlling parameters.     

Experimental and computational studies of the gas-phase reaction of halon 1211 with hydrogen

The gas-phase reaction of halon 1211 (CBrClF2) with hydrogen has been studied experimentally at atmospheric pressure in a plug flow, isothermal reactor over the temperature range of 673 to 973 K, at residence times ranging from 0.5 to 2.5 s with an input ratio of N2:H2:halon 1211 of 19:10:1. The major carbon containing products include CHClF2, CHBrF2, CH2F2, and CH4. Gas-phase reactions of CHClF2, CCl2F2, and CH2F2 with hydrogen are also investigated under the conditions similar to those for halon 1211 hydrodehalogenation, and the results are used to assist in understanding the mechanism of the reaction of halon 1211 with hydrogen. A kinetic reaction scheme involving 90 species and 430 reaction steps is developed and used to model the halon 1211 hydrodehalogenation reaction. Generally, satisfactory agreement between experimental and computational results is obtained for the production of major species. Using the software package AURORA, the reaction pathways leading to the formation of major products are elucidated. It has been found that the reaction steps involving CF2 are responsible for the formation of CH4.     

Dioxonaphthoimidazoliums are Potent and Selective Rogue Stem Cell Clearing Agents with SOX2‐Suppressing Properties

Pluripotent stem cells are uniquely positioned for regenerative medicine, but their clinical potential can only be realized if their tumorigenic tendencies are decoupled from their pluripotent properties. Deploying small molecules to remove remnant undifferentiated pluripotent cells, which would otherwise transform into teratomas and teratomacarcinomas, offers several advantages over non‐pharmacological methods. Dioxonapthoimidazolium YM155, a survivin suppressant, induced selective and potent cell death of undifferentiated stem cells. Herein, the structural requirements for stemotoxicity were investigated and found to be closely aligned with those essential for cytotoxicity in malignant cells. There was a critical reliance on the quinone and imidazolium moieties but a lesser dependence on ring substituents, which served mainly to fine‐tune activity. Several potent analogues were identified which, like YM155, suppressed survivin and decreased SOX2 in stem cells. The decrease in SOX2 would cause an imbalance in pluripotent factors that could potentially prompt cells to differentiate and hence decrease the risk of aberrant teratoma formation. As phosphorylation of the NF‐κB p50 subunit was also suppressed, the crosstalk between phospho‐p50, SOX2, and survivin could implicate a causal role for NF‐κB signaling in mediating the stem cell clearing properties of dioxonaphthoimidazoliums.     

Structural and ferroelectric properties of hafnium substituted BiFeO3 multiferroics synthesized via auto combustion technique

A series of BiFe_1-xHf_(3/4)xO₃ ( 0%, 5%, 10%, 15% and 20%) nanoparticles were synthesized by simple auto combustion technique using citric acid as a fuel. Thermogravimetric (TGA), differential thermogravimetric (DTA), structural, magnetic, dielectric and ferroelectric analyses were investigated. Thermogravimetric analysis provides information of temperature at which phase develops (600?°C). DTA predicts ferroelectric to paraelectric transformation temperature which is found to be 822?°C. X-ray diffraction (XRD) results confirm formation of distorted rhombohedral structure for all compositions along with few traces of Bi₂₅FeO₄₀. The tolerance factor is increased from 0.845 to 0.853 due to larger ionic radius of Hf⁴⁺ substitution on Fe site. Crystallite size (D) is found in the range of 24.2–30.48?nm. Saturation magnetization (Ms) is increased to 16 times and remanent magnetization (Mr) is increased to 8 times than that of pure BiFeO₃. This increment in magnetic parameters is due to reduction of oxygen vacancies, small crystalline size (less than 62?nm), structural distortion and unbalancing condition for antiferromagnetic magnetic moments of Fe³⁺ ions. Dielectric parameters depict decrement behavior with increasing of applied field up to 3?GHz. For Fe_1-xHf_(3/4)xO₃, lower value of dielectric permittivity for all compositions is due to reduction of polarization and less growth of grains but more growth of grain boundaries because of mismatching of Hf and Fe³⁺ ions. P-E hysteresis loop changes from round shape to elliptical shape and it confirms less lossy nature of ferroelectric loops. Higher values of Ms as well as Mr but lower values of dielectric constant as well as remanent polarization for these nanoparticles make them useful for MeRAM (magnetoelectric random access memory) and high resonant applications.