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Nanomedicine utilizes biocompatible nanomaterials for diagnostic and therapeutic purposes. The present study reports the use of Helicteres isora root extract for the synthesis of silver nanoparticles (AgNPs). The synthesized AgNPs were initially noticed through visual color change from yellow to reddish brown and further confirmed by surface plasmonic resonance (SPR) band at 450 nm using UV–visible spectroscopy. Morphology and size of AgNPs were determined by transmission electron microscopy (TEM) analysis. X-ray diffraction (XRD) study revealed crystalline nature of AgNPs. The prolonged stability of AgNPs was due to capping of oxidized polyphenols and carboxyl protein which was established by Fourier transform infrared spectroscopy (FTIR) study. In addition, the synthesized AgNPs were tested for antioxidant and antibacterial activities. It showed good antioxidant activity as compared to butylated hydroxytoluene (BHT) and ascorbic acid as standard antioxidant. It could be concluded that H. isora root extract can be used efficiently in the production of potential antioxidant and antibacterial AgNPs for commercial application.

It is clear from the growing role of ad exchanges in the real-time sale of advertising slots that Web publishers are considering a new alternative to their more traditional reservation-based ad contracts. To make this choice, the publisher must trade off, in real-time, the short-term revenue from ad exchange with the long-term benefits of delivering good spots to the reservation ads. In this paper we formalize this combined optimization problem as a multiobjective stochastic control problem and derive an efficient policy for online ad allocation in settings with general joint distribution over placement quality and exchange prices. We prove the asymptotic optimality of this policy in terms of any arbitrary trade-off between the quality of delivered reservation ads and revenue from the exchange, and we show that our policy approximates any Pareto-optimal point on the quality-versus-revenue curve. Experimental results on data derived from real publisher inventory confirm that there are significant benefits for publishers if they jointly optimize over both channels. Data, as supplemental material, are available at http://dx.doi.org/10.1287/mnsc.2014.2017 . This paper was accepted by Dimitris Bertsimas, optimization.

The development of reliable and eco-friendly methods for synthesizing metal nanoparticles is a pivotal step in advancing the field of nanotechnology. This comprehensive review discusses various synthesis routes and the applications of biosynthesized nanoparticles. The biosynthesis of metallic nanoparticles is the subject of a number of recent reviews, which focus on the various synthesis methods and characterization of the final products. The key applications reviewed here include biomedical applications, especially antimicrobial, antifungal, antiviral applications, also cytotoxicity effects, special embassies with molecular mechanism of silver nanoparticles in anticancer activity. It compares efficient synthesis methods via green routes to physical and chemical methods, which provide strong evidence for the selecting suitable method for the synthesis of silver nanoparticles. These findings will helpful for future investigations concerning the use of silver nanoparticles as different biomedical application in the areas of medical and food industry. Article HighlightsSilver nanoparticles as a potent antimicrobial, anticancer and antiviral application. Size, shape and structure of AgNPs are strictly dependent on the synthesis route.AgNPs cytotoxicity is a complex process, which related not only to silver ions release.Role of silver nanoparticles for different biomedical application.

Hyperhydricity (HH) is one of the major problems in plant tissue culture. Increased frequency (75%) of HH in the cultures of. Dianthus chinensis L. cultivar telstar scarlet raised from nodal segments on agar (0.85%) gelled, benzyladenine (2.5 µM) supplemented Murashige and Skoog (MS) medium was noticed in the third subculture onwards. To reduce HH and to resume normal growth, the addition of silver nitrate is routinely recommended in the culture medium. However, the impact of biogenic silver nanoparticles (AgNPs) on HH reversion has not been well investigated. In this study, biogenic AgNPs prepared from leaf extract of D. chinensis were used to control HH in D. chinensis cultures. The characterization of bioynthesized AgNPs has been done by UV–Vis spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction analysis, energy-dispersive X-ray spectrum, transmission electron microscopy, and atomic force microscopy. Higher water content or addition of ethylene precursor, ethephon, in culture medium induced plantlet with unhealthy, pale green, glassy shoots (HH). Due to the biological activity of Ag+ ions and water regulating mechanism, AgNPs treatment on hyperhydric explant (4 weeks) resulted in high retroversion coupled with reduced relative water content. Supplementation of 100 µg L−1 AgNPs in MS medium significantly reduced the percentage of HH to 13.3%, in contrast to control (100%). Addition of AgNPs effectively reduced hydrogen peroxide (H2O2) content (50%) characterized by green, healthy shoots with proper stomata in contrast to hyperhydric shoots. The gene expression pattern of 1-aminocyclopropane-1-carboxylase synthase (ACS1) and 1-aminocyclopropane-1-carboxylic acid oxidase (ACO1) showed reduced expression after the retroversion of microshoots in 100 µg L−1 AgNPs medium compared to hyperhydric shoot. The relative gene expression profile of ACS1 and ACO1 at 100 µg L−1 AgNPs treatment was 9.8 and 1.8-fold over normal shoots (1), respectively. Inter simple sequence repeat (ISSR) analysis on AgNPs directed HH reverted shoots showed genetic stability thus proved safe to adopt this technique to produce true to type plants. Combined manipulation, coordination of water permeability, and anti-ethylene activity of AgNPs were responsible for effective HH reversion. These finding will put forward the future utilization of bioencapsulated AgNPs in plant tissue culture and agriculture practices.Graphic Abstract

Many data analysis applications deal with large matrices and involve approximating the matrix using a small number of \"components.\" Typically, these components are linear combinations of the rows and columns of the matrix, and are thus difficult to interpret in terms of the original features of the input data. In this paper, we propose and study matrix approximations that are explicitly expressed in terms of a small number of columns and/or rows of the data matrix, and thereby more amenable to interpretation in terms of the original data. Our main algorithmic results are two randomized algorithms which take as input an $m\\times n$ matrix $A$ and a rank parameter $k$. In our first algorithm, $C$ is chosen, and we let $A'=CC^+A$, where $C^+$ is the Moore-Penrose generalized inverse of $C$. In our second algorithm $C$, $U$, $R$ are chosen, and we let $A'=CUR$. ($C$ and $R$ are matrices that consist of actual columns and rows, respectively, of $A$, and $U$ is a generalized inverse of their intersection.) For each algorithm, we show that with probability at least $1-\\delta$, $\\|A-A'\\|_F\\leq(1+\\epsilon)\\,\\|A-A_k\\|_F$, where $A_k$ is the \"best\" rank-$k$ approximation provided by truncating the SVD of $A$, and where $\\|X\\|_F$ is the Frobenius norm of the matrix $X$. The number of columns of $C$ and rows of $R$ is a low-degree polynomial in $k$, $1/\\epsilon$, and $\\log(1/\\delta)$. Both the Numerical Linear Algebra community and the Theoretical Computer Science community have studied variants of these matrix decompositions over the last ten years. However, our two algorithms are the first polynomial time algorithms for such low-rank matrix approximations that come with relative-error guarantees; previously, in some cases, it was not even known whether such matrix decompositions exist. Both of our algorithms are simple and they take time of the order needed to approximately compute the top $k$ singular vectors of $A$. The technical crux of our analysis is a novel, intuitive sampling method we introduce in this paper called \"subspace sampling.\" In subspace sampling, the sampling probabilities depend on the Euclidean norms of the rows of the top singular vectors. This allows us to obtain provable relative-error guarantees by deconvoluting \"subspace\" information and \"size-of-$A$\" information in the input matrix. This technique is likely to be useful for other matrix approximation and data analysis problems.

In this paper, for failure identification and insulation in a horizontal axis variable speed turbine made up of three sheets and one total converter, the vector support machines (SVM) is used. Data is based on the SVM method and so know-how is robust. It is also focused on the reduction of systemic risk this increases generalization and encourages method non-linearity accounting for the use of modular kernels. A radial function as a kernel has been used in this work. Various parts of the process, including actuators, sensors and process failures, have been investigated.

This article gives the best intellectual strength wind energy variable-speed point detection algorithm systems of transfer focused on improving instruction. Since reinforcing learning (RL) helps the variable - speed wind method to learn by direct contact with the environment. Awareness of factors of wind turbines or wind speed is not concerned. The first proposed MPPT control scheme facilitates a mix of the ANN and the Q-learning method to ensure the optimal coordination between PMSG engine speed and power. The proposed ANN-based RL MPPT control algorithm is supplied with simulation and experimental data.

Tungsten disulfide (WS 2 ) thin films were deposited on the glass substrate by varying its temperature from 350 to 500 °C using jet nebulizer spray pyrolysis (JNSP) technique. The WS 2 thin films were characterized through various techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), Energy dispersive X-ray analysis (EDX), UV–Visible spectroscopy (UV), photoluminescence (PL), Hall measurements and current–voltage (I–V) characteristics. XRD pattern revealed that the prepared WS 2 films are polycrystalline in nature with rhombohedral and hexagonal crystal structures. The average crystallite size of WS 2 thin films changed from 52.23 to 47.40 nm. SEM images showed the uniform grain size, which is agglomerated at the higher substrate temperature. The presence of elements like W and S was confirmed through EDX spectrum. From UV analysis, the minimum optical band gap and maximum absorption was obtained for the film deposited at 450 °C. The WS 2 thin films exhibited an n-type semiconductor nature with the carrier concentration of 10 14 cm −3 , which was demonstrated through hall measurements. Also, the electrical resistivity of the WS 2 films varied from 3.26 × 10 5 to 1.59 × 10 7  Ω cm. The p-Si/n-WS 2 junction diode was fabricated with various substrate temperature of (350–500 °C). Junction diode parameters like ideality factor (n), barrier height (ϕ B ) and reverse saturation current (I o ) values were calculated and interpreted based on the thermionic emission theory model.

Faced with handling multiple large data sets in modern data-processing settings, researchers have proposed sketch data structures that capture salient properties while occupying little memory and that update or probe quickly. In particular, the Count-Min sketch has proven effective for a variety of applications. It concurrently tracks many item counts with surprisingly strong accuracy.

Presently, the applications of optoelectronics products have assisted the fields of telecommunication in providing value-added products. In this sense, pure Tungsten disulphide (WS 2 ) and Copper doped WS 2 thin films are coated via the JNSP technique with different doping levels such as 1, 3, and 5 wt% of Cu, and the optimized substrate temperature of 450 °C. The morphology, structural, particle size, optical, and electrical properties of coated pristine and Cu-WS 2 thin films were characterized by scanning electron microscopy (SEM), energy dispersive microscopy (EDS), X-ray diffraction (XRD), UV spectra, Photoluminescence spectroscopic (PL) and Hall Effect measurements. The XRD results exhibit the prepared films have polycrystalline in nature with a tetragonal phase and the calculated crystallite size varied between 16 and 74 nm. The SEM images show the uniform grain size. The optical bandgap of 2.42 eV was obtained in the 5 wt% of Cu doped films. Hall measurements depicted that the pristine and Cu-doped WS 2 films have n-type behaviour with carrier concentration is about 10 8  cm −3 . Moreover, the fabricated p-Si/n-CuWS 2 diode parameters like ideality factor (n), barrier height (Φ B ), and reverse saturation current (I o ) values are measured.