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The purpose of this paper is to introduce Stancu variant of generalized Lupaş operators whose construction depends on a continuously differentiable, increasing and unbounded function ρ. Depending on the selection of γ and δ, these operators are more Ćexible than the generalized Lupaş operators while retaining their approximation properties. For these operators we give weighted approximation, Voronovskaya type theorem, quantitative estimates for the local approximation. Finally, we investigate the statistical approximation property of the new operators with the aid of a Korovkin type statistical approximation theorem. [ABSTRACT FROM AUTHOR]

Motivated by certain generalizations, in this paper we consider a new analogue of modified Szá sz-Mirakyan-Durrmeyer operators whose construction depends on a continuously differentiable, increasing and unbounded function τ τ with extra parameters μ μ and λ λ. Depending on the selection of μ μ and λ λ , these operators are more flexible than the modified Szá sz-Mirakyan-Durrmeyer operators while retaining their approximation properties. For these operators we give weighted approximation, Voronovskaya type theorem and quantitative estimates for the local approximation. [ABSTRACT FROM AUTHOR]

We construct Kantorovich variant of generalized Szász-Mirakjan operators whose construction depends on a continuously differentiable, increasing and unbounded function τ. For these new operators we give weighted approximation, Voronovskaya type theorem, quantitative estimates for the local approximation. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to introduce a Stancu type generalization of the Lupa¸s operators based on the q-integers. We investigate the rate of convergence of operators by mean of modulus of continuity and functions belonging to the Lipschitz class as well as Peetre’s K-functional. [ABSTRACT FROM AUTHOR]

The aim of this paper is to study a new generalization of Lupaş-type operators whose construction depends on a real-valued function ρ by using two sequences u m and v m of functions. We prove that the new operators provide better weighted uniform approximation over [ 0 , ∞) . In terms of weighted moduli of smoothness, we obtain degrees of approximation associated with the function ρ. Also, we prove Voronovskaya-type theorem, quantitative estimates for the local approximation. [ABSTRACT FROM AUTHOR]

The design and development of drug-delivery nanocarriers with high loading capacity, excellent biocompatibility, targeting ability and controllability have been the ultimate goal of the biomedical research community. In this work, we have reported the synthesis and characterization of novel and smart thermoresponsive polymer coated and Fe3O4 embedded hollow mesoporous silica (HmSiO2) based multifunctional superparamagnetic nanocarriers for the delivery of doxorubicin (Dox) for cancer treatment. P(NIPAM-MAm) coated and Fe3O4 nanoparticle (NP) embedded hollow mesoporous silica nanocomposite (HmSiO2-F-P(NIPAM-MAm)) was prepared by the in situ polymerization of NIPAM and MAm monomers on the surface of hollow mesoporous silica NPs (HmSiO2) in the presence of Fe3O4 NPs, oxidizer and crosslinker. TEM analysis showed nearly spherical morphology of HmSiO2-F-P(NIPAM-MAm) nanocarrier with a diameter in the range of 100–300 nm. The coating of P(NIPAM-MAm) layer and embedding of Fe3O4 NPs on the surface of the HmSiO2 NPs was revealed by HRTEM analysis. XRD and FTIR analysis also confirmed the presence of P(NIPAM-MAm) shells and Fe3O4 NPs on hollow mesoporous silica NPs. VSM analysis suggested the superparamagnetic nature of HmSiO2-F-P(NIPAM-MAm) nanocarrier. DSC analysis of HmSiO2-F-P(NIPAM-MAm) nanocarrier showed a phase transition at the temperature of ∼38 °C. The prepared HmSiO2-F-P(NIPAM-MAm) nanocarrier was investigated for its suitability for drug-delivery application using doxorubicin as the model drug by an in vitro method. The encapsulation efficiency and encapsulation capacity were found to be 95% and 6.8%, respectively. HmSiO2-F-P(NIPAM-MAm)-Dox has shown a pH and temperature-dependent Dox release profile. A relatively faster release of Dox from the nanocarrier was observed at temperature above the lower critical solution temperature (LCST) than below the LCST. HmSiO2-F-P(NIPAM-MAm) nanocarrier was found to be biocompatible in nature. In vitro cytotoxicity studies against Hela cells suggested that the HmSiO2-F-P(NIPAM-MAm)-Dox nanocomposite nanocarrier has good anticancer activity. In vitro cellular uptake study of HmSiO2-F-P(NIPAM-MAm)-Dox nanocomposite nanocarrier demonstrated its good internalisation ability into Hela cells. Thus, the prepared nanocomposites show potential as nanocarrier for targeted and controlled drug delivery for cancer treatment. [ABSTRACT FROM AUTHOR]

Biopolymer coated magnetic nanoparticles are becoming extremely popular in the fields of biomedical research because of their enormous applications potentials. In this work, first, CoFe 2 O 4 nanoparticles (CF NPs) of two distinct sizes have been prepared following co-precipitation method by varying the synthesis parameters and characterized. XRD, SAED and IFFT (Inverse Fast Fourier Transformed) assisted HRTEM analyses confirmed the successful formation of monodispersed spinel cubic CoFe 2 O 4 nanoparticles. Particles size of CF NPs was found to increase with increase in the amount of reducing agent. Synthesized CF NPs was coated with an egg albumen matrix by a facile and environmental friendly method to form biocompatible CoFe 2 O 4 @Albumen nanocomposite nanoparticle (CF@Alb NP). Prepared CoFe 2 O 4 and CoFe 2 O 4 @Albumen nanoparticles were examined for its structure, morphology, thermal stability and magnetic nature employing powder XRD, HRTEM, TGA, FTIR and VSM techniques. Low as well as high magnification TEM analyses have shown coating of amorphous albumen on crystalline CF NPs. It was observed that CF@Alb NP is composed of many smaller CF NPs engulfed in the albumen matrix forming a nano-aggregate of size ∼80–130 nm. IFFT analysis of HRTEM micrograph showed presence of crystalline CF NPs in amorphous albumen matrix. Further, TGA and FTIR results also suggested the successful coating of albumen on CF NPs. CF@Alb NP has shown a very good Dox loading ability with loading efficiency of ∼93%. A promising pH dependent Dox release behavior was observed. Dox release kinetics has also been studied using different mathematical models. Biocompatibility of the CF@Alb NP has been tested against the human monocytic cell line THP-1. This novel CF@Alb NP could have a great potential in biomedical applications, particularly in hyperthermia and targeted drug delivery. [ABSTRACT FROM AUTHOR]

Uses of biopolymers for the development of nanocarriers are receiving significant attention due to its biocompatible and biodegradable nature. Neem (Azadirachta indica) is a well known medicinal plant and it is reported that the polysaccharides and limonoids present in the neem extract prevent the growth and proliferation of cancer cells. In this work, we have synthesized neem gum (NG) coated Fe 3 O 4 nanoparticles (NPs) based novel nanobiocomposite (Fe 3 O 4 @NG NBC) by simple sonochemical method and characterized it for structural, microstructural and magnetic properties. The morphology, structure, and magnetic properties of the prepared Fe 3 O 4 NPs and Fe 3 O 4 @NG nanobiocomposite were investigated by X-ray diffractometer (XRD), Fourier-transform infrared (FTIR), Transmission electron microscopy (TEM), thermogravimetric analysis (TGA) and vibrating sample magnetometer (VSM) analysis. XRD pattern, TEM micrograph and FTIR spectra confirmed the successful coating of neem gum on Fe 3 O 4 nanoparticles. IR spectra of Fe 3 O 4 @NG nanobiocomposite revealed the presence of specific bands corresponding to both neem gum and Fe 3 O 4 NPs, which confirmed the formation of Fe 3 O 4 @NG NBC. The obtained size of Fe 3 O 4 @NG nanobiocomposite particles was ∼50–400 nm. VSM analysis confirmed the superparamagnetic nature of both Fe 3 O 4 NPs and Fe 3 O 4 @NG nanobiocomposite. Fe 3 O 4 @NG nanobiocomposite was loaded with anticancer drug doxorubicin (Dox) and its release behaviour was studied at pH 7.4 and 5. Faster release of Dox was observed in acidic environment. In vitro cytotoxicity of the prepared Fe 3 O 4 @NG NBC against human monocytic cell line THP‐1 was also studied by MTT assay. This novel Fe 3 O 4 @NG nanobiocomposite with low toxicity, biodegradability, water dispersability, excellent drug loading ability and good magnetic controllability could offer potential applications in biomedical field including targeted drug delivery for cancer diagnosis and treatment in near future. [ABSTRACT FROM AUTHOR]

A novel visible light active and magnetically separable nanophotocatalyst, Ni 0.5 Zn 0.5 Fe 2 O 4 /Zn 0.95 Ni 0.05 O (denoted as NZF@Z), with varying amount of Ni 0.5 Zn 0.5 Fe 2 O 4 , has been synthesized by egg albumen assisted sol gel technique. The structural, optical, magnetic, and photocatalytic properties have been studied by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), fourier transform infrared spectroscopy (FTIR), UV–visible (UV–Vis) spectroscopy, and vibrating sample magnetometry (VSM) techniques. Powder XRD, TEM, FTIR and energy dispersive spectroscopic (EDS) analyses confirm coexistence of Ni 0.5 Zn 0.5 Fe 2 O 4 and Zn 0.95 Ni 0.05 O phases in the catalyst. Crystallite sizes of Ni 0.5 Zn 0.5 Fe 2 O 4 and Zn 0.95 Ni 0.05 O in pure phases and nanocomposites, estimated from Debye–Scherrer equation, are found to be around 15–25 nm. The estimated particle sizes from TEM and FESEM data are ∼(22 ± 6) nm. The calculated energy band gaps, obtained by Tauc relation from UV–Vis absorption spectra, of Zn 0.95 Ni 0.05 O, 15%NZF@Z, 40%NZF@Z and 60%NZF@Z are 2.95, 2.72, 2.64, and 2.54 eV respectively. Magnetic measurements (field (H) dependent magnetization (M)) show all samples to be super-paramagnetic in nature and saturation magnetizations (M s ) decrease with decreasing ferrite content in the nanocomposites. These novel nanocomposites show excellent photocatalytic activities on Rhodamin Dye. [ABSTRACT FROM AUTHOR]

Abstract: In recent years, polyaniline/CoFe2O4 nanocomposites have gained attention because of their wide utilization in optoelectronics and biomedical studies. However, very limited research has been carried out on the anticandidal activity of polyaniline/CoFe2O4 nanocomposite against Candida spp. Thus, the study was designed to investigate the anticandidal potential of PANI/CoFe2O4 nanocomposite against Candida albicans 077. PANI/CoFe2O4 nanocomposite (denoted as “cfPNCs”) was synthesized by polymerization of aniline in the presence of CoFe2O4 nanoparticles. The structural and thermal properties of the synthesized PANI/CoFe2O4 nanocomposite were investigated. It was noteworthy that PANI/CoFe2O4 nanocomposite showed promising anticandidal activity in a dose-dependent manner. Results also showed that the protection of histidine (a ROS quencher) against ROS clearly suggested the implication of ROS in anticandidal activity of PANI/CoFe2O4 nanocomposite. It is encouraging to conclude that PANI/CoFe2O4 nanocomposite bears the potential of their applications in biomedicine, especially nanotherapy for diseases caused by C. albicans. [Copyright &y& Elsevier]

Highlights: [•] PANI/CoFe2O4 nanocomposites (PANI@CF-1:1 and 1:2) have been successfully synthesized. [•] Nanocomposites properties modified by the addition of varying amount of the CoFe2O4 NPs into the PANI. [•] Nanocomposite (PANI@CF-1:2) showed the photocatalysis of MO dye via production of ROS. [Copyright &y& Elsevier]

The main aim of this paper is to establish summation-integral type generalized Lupaş operators with weights of Beta basis functions which depends on μ having some properties. Primarily, for these new operators, we calculate moments and central moments, weighted approximation is discussed. Further, Voronovskaya type asymptotic theorem is proved. Finally, quantitative estimates for the local approximation is taken into consideration. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to introduce q-analogues of generalized Lupaş operators, whose construction depends on a continuously differentiable, increasing, and unbounded function ρ. Depending on the selection of q, these operators provide more flexibility in approximation and the convergence is at least as fast as the generalized Lupaş operators, while retaining their approximation properties. For these operators, we give weighted approximations, Voronovskaja-type theorems, and quantitative estimates for the local approximation. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to introduce a new modification of Lupas operators in the frame of post quantum setting and to investigate their approximation properties. First using the relations between q-calculus and post quantum calculus, the post quantum analogue of operators constructed will be linear and positive but will not follow Korovkin's theorem. Hence a new modification of q-Lupas operators is constructed which will preserve test functions. Based on these modification of operators, approximation properties have been investigated. Further, the rate of convergence of operators by mean of modulus of continuity and functions belonging to the Lipschitz class as well as Peetre's K-functional are studied. [ABSTRACT FROM AUTHOR]

In this paper, a compact and broadband mode converter and demultiplexer based on multimode interference (MMI) is designed and experimentally demonstrated on silicon-on-insulator. We have designed a mode converter using cascaded MMI to convert the fundamental mode into a higher-order (first-order mode) and vice versa. Subsequently, we have demonstrated an on-chip two-mode demultiplexer with a compact footprint and low loss. The proposed mode demultiplexer shows low insertion loss (0.22 dB for ${{\rm TE}&#95;0}$TE 0 and 0.36 dB for ${{\rm TE}&#95;1}$TE 1 mode) and crosstalk (${-}{25.2}\;{\rm dB}$-25.2dB for ${{\rm TE}&#95;0}$TE 0 and ${-}{24.4}\;{\rm dB}$-24.4dB for ${{\rm TE}&#95;1}$TE 1 mode) at wavelength 1550 nm using the eigenmode expansion method. Moreover, the device supports a broad bandwidth having crosstalk ${ \lt } {-} {20}\;{\rm dB}$<-20dB over a wavelength range of 1520-1580 nm. The proposed device can be used in mode division multiplexing for photonic network-on-chip.

In the present work, multifunctional Ni 0.5 Zn 0.5 Fe 2 O 4 @albumen (NZF@Alb) and doxorubicin-loaded Ni 0.5 Zn 0.5 Fe 2 O 4 @albumen (NZF@Alb-Dox) core-shell nanoparticles have been prepared by a green and simple method using inexpensive chicken egg albumen and have been characterized for different physiochemical properties. The structural, morphological, thermal, and magnetic properties of the prepared nanoparticles have been investigated by an x-ray diffractometer, high-resolution transmission electron microscopy (HRTEM), field emission scanning electron microscopy, Fourier-transformed infrared, thermogravimetric analysis, and vibrating sample magnetometer techniques. Superparamagnetic Ni 0.5 Zn 0.5 Fe 2 O 4 nanoparticles (NZF NPs) with the mean size ∼20 nm were coated with albumen matrix by an ultrasonication process. Inverse fast Fourier transform-assisted HRTEM micrographs and FTIR analysis revealed the coating of amorphous albumen on crystalline NZF NPs. NZF@Alb and NZF@Alb-Dox NPs have the mean size (D 50 ) of ∼100 nm, good stability, and magnetic controllability. Magnetic measurements (field (H)-dependent magnetization (M)) show all samples to be super-paramagnetic in nature. Biocompatibilities of the NZF and NZF@Alb NPs were confirmed by in vitro 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay against RAW 264.7 cells. NZF@Alb NPs have been found to be more biocompatible than bare NZF. In Vitro Dox release behavior from NZF@Alb-Dox NPs has been studied at pH 7.4 and 5, and a sustained and pH-dependent drug release profile were observed. In vitro cytotoxicity or anticancer activity of the blank NZF@Alb NPs, free Dox, and NZF@Alb-Dox NPs against HeLa cells (cancer cell line) were also examined by MTT assay. The obtained results suggest that this scalable egg-albumen-based magnetic nanoformulation is suitable for targeted drug delivery applications. Thus, the present study could be extremely useful for the advancement of albumin-based nanocarrier design and development for biomedical applications such as targeted and controlled delivery of anticancer drugs.