Gastroprotective effects of herbal medicines (roots)

Herbal medicines are now commonly used all over the world and this has increased global demand. Quality, safety, and efficacy of these drugs have become a serious concern. This review presents the medicinal plants cited in folklore that are used to treat gastrointestinal ulcers. Electronic databases, that is, Web of Science, PubMed, Scopus, and Google Scholar were searched to identify the gastroprotective effects of each plant. Ethnopharmacological studies have reported various botanical products with antiulcer activities, but there has been limited scientific research, presenting clinical data to validate the efficacy and safety of medicinal herbs as gastroprotective agents. Most studies centered on pharmacological properties of medicinal herbs as used animals models. This information has prompted us to compile a list of the medicinal herbs cited in folklore with gastroprotective activity.     

Electrophoretic deposition of bioactive glass nanopowders on magnesium based alloy for biomedical applications

To slow down the initial biodegradation rate of magnesium (Mg) alloy, crystalline nano-sized bioactive glass coating was used to deposit on micro-arc oxidized AZ91 samples via electrophoretic deposition (EPD). Zeta potential and conductivity of the bioactive glass suspension were characterized at various pH values to identify the most stable dispersion conditions. The bone-bonding properties of bioactive glass coated samples were evaluated in terms of apatite-forming ability during the immersion in simulated body fluid (SBF) solution. Results revealed that the ability to form a bioactive glass coating via EPD was influenced by the degree of its crystalline phase composition. Moreover, the potentiodynamic polarization tests recorded significant drops in corrosion current density and corrosion rate of the coated samples which implies a good level of corrosion protective behavior. These preliminary results show that this process will enable the development of Mg implants in the later stage of bone healing.     

Reliability Improved Stochastic Dynamic Programming for Reservoir Operation Optimization

Stochastic Dynamic Programming (SDP) is widely used in reservoir operation problems. Besides its advantages, a few drawbacks have leaded many studies to improve its structure. Handling the infeasible conditions and curse of dimensionality are two major challenges in this method. The main goal of this paper is proposing a new method to avoid infeasible conditions and enhance the solution efficiency with new discretization procedure. For this purpose, an optimization module is incorporated into regular SDP structure, so that, near optimal values of state variables are determined based on the available constraints. The new method (RISDP) employs reliability concept to maximize the reservoir releases to satisfy the downstream demands. Applying the proposed technique improves the reservoir operating policies compared to regular SDP policies with the same assumptions of discretization. Simulation of reservoir operation in a real case study indicates about 15% improvement in objective function value and elimination of infeasible conditions by using RISDP operating policies.     

Optical Pattern Switching in Semiconductor Microresonators as All‐Optical Switch

In this paper, we present a spatial perturbation method to control the optical patterns in semiconductor microresonators in the far‐field configuration. We propose a fast all‐optical switch which operates at a low light level. The switching beam controls the behavior of output beams with strong intensities. The method has been applied successfully to different optical patterns such as rolls, squares, and hexagons.     

The development of spectral indices for detecting built-up land areas and their relationship with land-surface temperature

ABSTRACT

Different spectral indices were provided for the classification of built-up lands using satellite images, but the importance of the blue band in the classification, fusion, and image enhancement prior to the calculation of spectral indices has received less attention so far. This study introduces a new index based on blue band and run it along with six other spectral indices. The method of study is as follows, after the selection of Landsat 7 and Landsat 8 images, the initial pre-processing was done on the images and in the second stage, the enhancement and the fusion were performed. In the third stage, the built-up lands were classified using spectral indices. Otsu’s thresholding method was used on all indices to separate built-up and non-built-up lands. To assess the accuracy, 3500 reference points were used. The results showed that when fusion and image enhancement were performed, overall accuracy (OA) increased by 3% to 6.71% for Landsat 7 images, and 2.14% to 6.71% for Landsat 8 images. The results also showed that after fusion and image enhancement, the visible blue band and first shortwave infrared index (VbSWIR1-BI) with an OA of 92.88% (Landsat 7) and 91.68% (Landsat 8) indicate the highest OA. The percentage of built-up lands changes according to spectral indices ranges from 6.38% to 25 .76% and the largest and lowest amount of built-up land on the basis of the VbSWIR1-BI index belonging to districts 12 and 22, respectively. The results of the spectral indicator show dispread growth during the 14 year period for Tehran. Finally, a significant relationship was observed between surface temperature and built-up land classified by spectral indices.     

Biosynthesis of reusable and recyclable CuO@Magnetite@Hen Bone NCs and its antioxidant and antibacterial activities: a highly stable magnetically nanocatalyst for excellent reduction of organic dyes and adsorption of polycyclic aromatic hydrocarbons

For the first time, through a fast, eco‐friendly and economic method, the aqueous extract of the leaf of Euphorbia corollate was used to the green synthesis of the highly stable CuO@Magnetite@Hen Bone nanocomposites (NCs) as a potent antioxidant and antibacterial agent against Pseudomonas aureus, Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae pathogenic bacteria. The biosynthesised NCs were identified using the scanning electron microscopy (SEM), energy dispersive X‐ray spectroscopy, elemental mapping, X‐ray diffraction (XRD), Fourier transforms infrared spectroscopy and UV–vis analytical techniques. Also, the radical scavenging activity using (2,2‐diphenyl‐1‐picrylhydrazyl) method was used to evaluate the antioxidant activity of the NCs. The stability of nanocatalyst was monitored using the XRD and SEM analyses after 30 days from its synthesis. Furthermore, its excellent catalytic activity, recycling stability, and high substrate applicability were demonstrated to the adsorption of the polycyclic aromatic hydrocarbons of the light crude oil from Shiwashok oil fields and destruction of methylene blue and methyl orange as harmful organic dyes at ambient temperature using UV–vis spectroscopy. Moreover, the green CuO@Magnetite@Hen Bone NCs were recovered and reused several times without considerable loss of its catalytic activity.Inspec keywords: nanobiotechnology, X‐ray diffraction, infrared spectra, catalysis, crude oil, Fourier transform spectra, ultraviolet spectra, scanning electron microscopy, dyes, catalysts, photochemistry, iron compounds, X‐ray chemical analysis, antibacterial activity, adsorption, visible spectra, microorganisms, organic compounds, reduction (chemical), nanomedicine, toxicology, recycling, chemical industryOther keywords: antioxidant activity, XRD, SEM analyses, recycling stability, polycyclic aromatic hydrocarbons, harmful organic dyes, UV–vis spectroscopy, green CuO@Magnetite@Hen Bone NCs, reusable CuO@Magnetite@Hen Bone NCs, recyclable CuO@Magnetite@Hen Bone NCs, antioxidant activities, antibacterial activities, highly stable magnetically nanocatalyst, eco‐friendly method, economic method, euphorbia corollate, green synthesis, CuO@Magnetite@Hen Bone nanocomposites, antibacterial agent, pseudomonas aureus, staphylococcus aureus, escherichia coli, klebsiella pneumoniae pathogenic bacteria, biosynthesised NCs, X‐ray spectroscopy, X‐ray diffraction, radical scavenging activity, antioxidant agent, 2,2‐diphenyl‐1‐picrylhydrazyl, catalytic activity, organic dye reduction, light crude oil, CuO     

Improving performance of neurons by adding colour noise

Noise is not always an interfering signal which perturbs the system. On the contrary, noise signals can enhance the performance of some non‐linear systems such as stochastic resonance (SR). These systems can detect the weak input signal when it is added to the noise signal. According to this property, SR models play a significant role in the functioning of the brain for detecting weak input signals and synchronisation of neural connections. In this study, the authors model neurons as SR systems where different types of noise, i.e. white noise and pink noise, are employed to amplify the weak nervous signals. They demonstrate colour noise, in particular, pink noise enhances the performance of the SR system to amplify the input signal. Furthermore, pink noise has a wider range of optimum values in comparison to white noise. Therefore, they can conclude that neurons are more sensitive to detect the signals that carry pink noise than signals with white noise or without noise. Hence, the retrieving ability of neurons can be improved by adding pink noise.Inspec keywords: stochastic processes, white noise, neural nets, brain, noise, neurophysiologyOther keywords: interfering signal, particular noise, colour noise, weak nervous signals, pink noise, white noise, SR system, authors model neurons, SR models, noise signal, weak input signal, nonlinear systems     

Chemical composition and antioxidative activity of Moldavian balm (Dracocephalum moldavica L.) extracts

Moldavian balm (Dracocephalum moldavica L., Lamiaceae) is a perennial herb native to central Asia and naturalized in eastern and central Europe. It is commonly consumed as a food-related product and as a herbal preparation because of its reputed medicinal properties. Despite its importance, few reports exist in the literature regarding the chemistry or antioxidant activity of this species. In this study, the aerial material of Moldavian balm collected from Iran was extracted by Soxhlet using seven solvents of different polarity, viz., petroleum ether, dichloromethane, acetonitrile, ethyl acetate, methanol, n-butanol and water. The qualitative-quantitative chemical composition of each extract was determined using high-performance liquid chromatography coupled to photodiode array detection. For each extract, the total phenolic content was estimated as was the in vitro antioxidant activity using the iron(III) reduction assay, the β-carotene-linoleic acid bleaching assay and the 1,1-diphenyl-2-picrylhydrazyl and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulphonate) free radical scavenging assays. Hydroxylated cinnamic acids, their derivatives and flavonoids were identified and quantified within the extracts, with rosmarinic acid being the most abundant component identified. The extracts demonstrated different degrees of potency within each assay, however, the observed pattern was not necessarily replicated between assays indicating the importance of the use of more than one screening technique to estimate the antioxidant activity of plant extracts.     

Chemical composition and in vitro antioxidative activity of a lemon balm (Melissa officinalis L.) extract

The leaf material of lemon balm (Melissa officinalis L.) was extracted with 450 ml/l aqueous ethanol by medium pressure liquid-solid extraction. The total phenolic content of the extract was estimated as gallic acid equivalents by Folin-Ciocalteu reagent method and a qualitative-quantitative compositional analysis was carried out using high performance liquid chromatography coupled with photodiode array detection. The lemon balm extract contained hydroxycinnamic acid derivatives and flavonoids with caffeic acid, m-coumaric acid, eriodictyol-7-O-glucoside, naringin, hesperidin, rosmarinic acid, naringenin, hesperetin being identified based on their chromatographic behaviour and spectral characteristics. The extract was also investigated for potential in vitro antioxidant properties in iron(III) reduction, iron(II) chelation, 1,1-diphenyl-2-picrylhydrazyl, 2,2′-azinobis(3-ethylbenzothiazoline-6-sulphonate), superoxide anion and nitric oxide free-radical scavenging, and inhibition of β-carotene-linoleic acid bleaching assays. The extract demonstrated antioxidant activity in all the assays. However, it was not as potent as the positive controls except in the β-carotene-linoleic acid bleaching assay, where its activity was superior to that of gallic and caffeic acids and statistically indistinguishable from quercetin and BHA. The exceptionally high antioxidant activity and the fact that this assay is of biological relevance warrants further investigation of lemon balm extract in ex vivo and in vivo models of oxidative stress.     

Comparison between visible and near-IR flame spectra from natural gas-fired furnace for blackbody temperature measurements

This paper reports the results from investigating the feasibility of calculating flame temperature from a natural gas-fired furnace based on blackbody radiation in the visible spectral range. If successful, the visible spectral range would provide data for multi-task applications such as emission line analysis and temperature calculation simultaneously. A probe containing a lens connected to the fiber-optic cables is inserted into the furnace and pointed towards the flame. Spectral intensity data are fed back to a spectrometer and then to a monitoring computer. The approach is first applied to various furnace types using the visible range to establish a baseline for the technique. The results for temperature calculations in the visible range are then compared with those taken in the near-IR (NIR) range under the same conditions. This comparison indicates that temperatures calculated from visible region could be as accurate as the one obtained from NIR region. Challenges associated with this technique are also discussed.