Iranian Journal of Science and Technology, Transactions A: Science最新文献

Let ({mathcal {S}}) and ({mathfrak {B}}) be two unital (*)-algebras such that ({mathcal {S}}) has a nontrivial projection. In the present article, we demonstrate, under certain restrictions that if a bijective map (Delta :{mathcal {S}}rightarrow {mathfrak {B}}) satisfies (Delta (Mdiamond N circ W) = Delta (M)diamond Delta (N)circ Delta (W)) for all (M, N, W in {mathcal {S}}), then (Delta) is a (*)-preserving ring isomorphism. As an application, we will describe these mappings on factor von Neumann algebras.

A series of twenty-two new trifloromethyl benzimidazole derivatives were prepared based on azide and DCC coupling of 2-(2-(trifluoromethyl)-1H-benzoimidazol-1-yl) ethanoic acid derivatives with amino acids to give the amino acid esters; methyl 2-[(2-(2-(trifluoromethyl)-1H-benzimidazol-1-yl)acetamido] alkanoates. The amino acid esters reacted with hydrazine to produce the corresponding hydrazides that were finally condensed with p-fluorobenzaldehyde to obtain the hydrazones. The synthesized compounds were evaluated for their ability to bind to the crystal structure of E. coli (PDB = 1KZN) and the crystal structure of S. aureus (PDB = 1JIJ) bacteria, revealing good binding affinities. Notably, compounds 5e and 5k demonstrated primising interactive binding mode with the key amino acids like the co-crystallized ligands. As a result, they can be further tested as potent antimicrobial agents.

We study the linear finite element approximation of thermoelastic frictional contact problem. The unilateral contact condition is weakly imposed by the penalty method. Our analysis yields error estimates that are contingent upon the penalty parameter (varepsilon) and the mesh size h. Furthermore, provided the solution maintains regularity, we establish a convergence result.

This paper presents a polynomial sinc-based collocation method, combined with Gauss–Legendre/Newton–Cotes quadrature rules, to solve stochastic fractional integro-differential equations (SFIDEs). The method approximates the solution by applying Lagrangian polynomial interpolation at sinc collocation points and simplifies the SFIDE into a system of algebraic equations, requiring low/moderate computational efforts. The proposed method is also accompanied by an error analysis, and numerical examples are provided to demonstrate its efficiency and accuracy. In noiseless conditions, the method achieves spectral accuracy and behaves like other conventional sinc methods. Finally, the paper simulates an application of a class of these equations.

In this work, we introduce a feasible and efficient method for solving weakly singular fractional pantograph delay integro-differential equations. To implement the proposed method, we get the operational matrices based on the shifted fractional-order fifth-kind Chebyshev polynomials. These matrices, together with the collocation method, are applied to convert the main equation to a system of algebraic equations. We consider the existence and uniqueness of solutions and then give an upper error bound for this method. At last, several numerical tests are carried out to demonstrate the usefulness and capability of the suggested algorithm.

During an epidemic outbreak, slowing the infection among the population can be achieved through two major approaches: raising awareness about the disease and quarantining the infected population. Elevating awareness levels among the population is essential for slowing down the infection. In this study, our goal is to propose and mathematically analyze a novel Caputo derivative-based fractional-order Susceptible–Aware–Infected–Quarantined–Recovered–Susceptible compartmental model. The model is developed by incorporating the level of awareness among the population, explicit non-monotone incidence rates for new infection cases, and a saturated quarantine rate for the infected population. Additionally, this study aims to capture the complex dynamics of infectious diseases in the absence of any vaccine to control the disease spread. The qualitative study of the model reveals two equilibria: an infection-free equilibrium and an endemic equilibrium. We obtain that the infection-free equilibrium is locally asymptotically stable when the basic reproduction number is below one. Furthermore, we investigate the model for the possible occurrence of multiple positive equilibria and examine the local stability of the endemic equilibrium, showing that it is locally asymptotically stable under certain conditions when the basic reproduction number is above unity. Finally, we present numerical simulations to support our analytical findings.

Therapeutic proteins need to be produced in large quantities as they continuously gain higher shares in pharmaceutical market. Human beta interferon (hIFN-β) is used against different diseases due to its antiviral, antiproliferative and immunomodulatory nature. Considering its clinical applications, development of a simple, cost-effective and easily scalable production system to produce rhIFN-β-1b protein in high yield and quality is needed. Attempts to develop improved production methods are ongoing. Majority of previous reports propose isopropyl-β-D-1-thiogalactopyranoside (IPTG), for rhIFN-β-1b expression in Escherichia coli, which is costly and nonmetabolizable. Thus, in current study, rhIFN-β-1b expression was optimized in an inexpensive auto-induction medium. Corn steep liquor (CSL) was used and optimized at different concentrations. Further, the medium was also optimized for carbon sources using various glycerol concentrations. Finally, a 10 L fermentation batch was done (10% CSL and 2.5% glycerol) that produced 65 g of wet biomass and 15 g of inclusion body (wet). The purification scheme was optimized by one-step ion-exchange chromatography (IEX) for > 99% purity of the target protein. The biological activity of the required protein was assessed through cytopathic inhibition effect of virus vesicular stomatitis (VSV) on Madin-Darby bovine kidney (MDBK) cells. Moreover, cytotoxicity of the protein was also studied on different breast cancer cell lines; HCC- 1954, MCF- 7 and MDA- MB- 231. This is the first report on utilizing CSL as auto-induction media for expression and purification of rhIFN-β-1b. Thus, the suggested method can be employed for simple as well as cost-effective production of rhIFN-β-1b and other recombinant proteins.

Wheat (Triticum aestivum L.) is a global staple cereal known for its nutritional value and economic significance. Somatic embryogenesis (SE) is a powerful biotechnological tool for plant genetic improvement, driven by intricate epigenetic mechanisms as well as controlled by key genes such as Wuschel-related HOMEOBOX (WOX4), Leafy cotyledon (LEC1), Baby Boom 1 (BBM1), and Somatic embryogenesis receptor kinase (TaSERK). This study investigates the impact of different concentrations (0.1, 0.5, 1, and 2 µM) of Trichostatin A (TSA) and 5-Azacytidine (5-Azac), recognized epigenetic inhibitors, on mature embryos of Kırık bread wheat variety cultured in a callus formation medium. In vitro parameters including Callus formation frequency (CFF) (mg), callus fresh weight (CFW) (%), embryogenic callus formation frequency (ECFF) (%), embryogenic callus frequency (RECF) (%), and regeneration efficiency (RE) (number) as well as expression levels of WOX4, LEC1, BBM1, and TaSERK genes, were evaluated at 14, 28, and 42 days after initiation of tissue culture (DAI). The results show that TSA and 5-Azac treatments had a considerable influence on the in vitro parameters tested. Furthermore, these compounds had a significant effect on the mRNA expression levels of the WOX4, LEC1, BBM1, and TaSERK genes, which are important in SE. Specifically, LEC1 expression peaked at 42 DAI across all treatments, while WOX4 and BBM1 peaked at 14 DAI. TaSERK expression decreased by 42 DAI, with variations depending on treatment at previous time points. As a result of this study, 0.5 µM TSA and 5 µM 5-Azac treatments resulted in optimal plant regeneration, emphasizing the importance of epigenetic regulators in promoting somatic embryogenesis via endosperm-supported mature embryo in wheat. This study suggests addressing epigenetic systems to improve SE protocols and inform wheat genetic engineering and breeding initiatives for sustainable agriculture and food security.

Spontaneous quaternary fission accompanied by two α particles for isotopes ³⁰⁴120 in both equatorial and collinear configurations, and for ^298,302120 in the equatorial configuration has been studied using Coulomb and proximity potential model with the inclusion of deformation and orientation of fragments. The most favourable quaternary fission channel is determined using cold reaction valley and relative yield plots. In the case of ³⁰⁴120, the equatorial emission of light charge particles displays distinct peaks, reaching a peak relative yield of approximately 33.65%. In contrast, collinear emission shows continuous peaks with a maximum relative yield around 1.27%. The peak relative is attributed to the presence of nuclei ¹²¹In for equatorial emission, and ¹²²I, ¹⁹²Au, ⁹⁷Ru and ⁴²Cl for collinear emission. For the parent isotopes ³⁰²120 a peak relative yield around 19.44% is obtained for combination containing nuclei ¹²²Ag, whereas in the case of ²⁹⁸120, fission channels result in a maximum relative yield of approximately 22.08% with one fragment as ¹²²Ag. The mentioned nuclei are found to possess either a magic number of protons or neutrons leading to shell closure. In addition to closed shell effect, the inclusion of deformation factors β_2, β₄ and orientation of fragments have a prominent role in determining the relative yield of a particular fission channel.

In this study, we present a technique for enhancing the order of approximation of the modified form of the Bernstein operators that Usta F. achieved. Moreover, two novel operators with degrees of approximation one and two are obtained. Furthermore, we validate a few theoretical findings such as the Korovkin theorem, Voronovskaja theorem, modulus of continuity, etc. about the rate of convergence of these operators. In the end, we operate graphs and tables to illustrate the comparison between the constructed operators and compute the numerical verification of the theoretical conclusions.