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Endophytic fungi have been a focus of attention for producing diverse classes of bioactive metabolites but little is known about endophytic fungi Aureobasidium pullulan, isolated from the bark of frankincense producing tree (Boswellia sacra). Extensive chromatographic methods resulted in the isolation of two known diketopeprazin (1 and 2) along with three fatty acids derivatives (3–5) from the ethyl acetate fraction of Aureobasidium pollulan BSS6. The structures of mentioned compounds were characterized by advanced 1D and 2D spectroscopic techniques such as, ultraviolet–visible (UV), infrared (IR), electrospray ionization mass spectrometry (ESI-MS) 1H NMR, 13C NMR, heteronuclear multiple bond correlation (HMBC), heteronuclear multiple-quantum coherence (HMQC) and correlation spectroscopy (COSY). The resulted compounds were evaluated for α-glucosidase inhibition potential to know their hyperglycemic effect in type 2 diabetes mellitus. Compound 3 showed significant inhibition having an IC50 value of 23.3 µM. To know the binding energy and pharmacophore of compound 3 with in active site of enzyme, the molecular docking was performed. Compound 3 has shown π-alkyl type of interactions with Asp214 and Glu276, key amino acid residues in the catalytic triad of α-glucosidase. In conclusion, the current study reports novel sources of anti-diabetic constituent's from Aureobasidium sp. for the first time.

Ambient light noise is a major cause of performance degradation in visible light communication (VLC) systems. It affects outdoor VLC applications in terms of signal to noise ratio (SNR) and bit error rates (BER). Sunlight plays an important role in increasing the effects of ambient noise on VLC signal. VLC is suggested as a promising communication mode between two vehicles, in vehicle-to-vehicle (V2V) communication systems. In this paper, we discuss and propose an efficient method to overcome the effect of sunlight irradiance in VLC links used for V2V communication. We propose K-Nearest Neighbour (KNN), a machine learning-based adaptive filter to combat the effects of solar irradiance. Our smart filter can adapt itself according to varying noise conditions and help to achieve acceptable BER in support of reliable communications.

In this research work, we proposed a Haar wavelet collocation method (HWCM) for numerical solution of linear and nonlinear Schrodinger equations. The nonlinear term present in the model equation is linearized by a linearization technique. The Time derivative in the Schrodinger equation is approximated by forward Euler difference formula while the space derivatives are approximated by Haar function, which convert the model equation into system of algebraic equation. The stability analysis of the HWCM is also given. Several test problems are presented to verify the accuracy, stability and capability of the proposed method.

Lens-less microscopy can achieve a wide field of view imaging (FOV) through a simple configuration compared to conventional microscopy, and it is very attractive in resource-limited areas because of its cost-effectiveness and portability. Featuring a small package and cheapness, LEDs and LDs both show the potential to act as a reasonable illumination source for lens-less microscopes, especially for portable ones. However, based on holographic theorem, the complex light-field reconstruction algorithms consider the light source as a highly coherent one, while both LEDs and LDs can only provide partially coherent illumination. In this manuscript, we would systematically and experimentally analyze the imaging performances of lens-less microscopy with partially coherent illumination. The analysis covers autofocusing under LED/LD illumination, imaging performances under different LED spatial coherence and imaging performances under LED/LD illumination. Furthermore, based on the analysis, some conclusions about designing a lens-less microscope are presented. We think that the experiments and conclusions can provide effective guidance to construct a low-cost lens-less microscope with trade-off hardware parameters in practices.

Multi-spectral imaging technology is helpful to obtain better contrast and more details of images at different wavelengths compared with monochromatic imaging or conventional RGB imaging technologies. And in resource-limited areas, microscopes with features of low-cost and portability are extremely attractive. In this manuscript, we demonstrate that cost-effective lens-less microscopy can be combined with the multi-spectral imaging technology, which can be alternative to conventional approaches and applied in biology, chemistry, environmental science. As a proof of this concept, we present a novel portable multi-spectral lens-less microscope (MSLLM). An outstanding highlight of our setup is its wavelength-self-calibrating imaging sensor (WSCIS), which can provide computationally optimized wavelength value (COWV) for LED illumination in real time. For each illumination, 5 holograms of the sample at 5 different heights are captured. Through the COWVs and phase retrieval algorithms, 7 multi-spectral images (FOV: 4.8 mm*4.6 mm, resolution: ∼1 µm) can be reconstructed. We believe that our MSLLM can be widely applied to multi-spectral microscopy in low-cost required scenes.

In this paper, a Haar wavelet collocation method (HWCM) is developed for PDEs related to the framework of so-called inverse problem. These include PDEs with unknown time dependent heat source and unknown solution in interior of the domain. To this end, a transformation is used to eliminate the unknown heat source to obtain a PDE without a heat source. After elimination of unknown non-homogeneous term, an implicit finite-difference approximations is used to approximate the time derivative and Haar wavelets are used for approximation of the space derivatives. Several numerical experiments related to one- and two-dimensional heat sources are included to validate small condition number of coefficient matrix, accuracy and simple applicability of the proposed approach.

The present analysis is devoted to explore the computational solution of the problem addressing the variable viscosity and inclined Lorentz force effects on Williamson nanofluid over a stretching sheet. Variable viscosity is assumed to vary as a linear function of temperature. The basic mathematical modelled problem i.e. system of PDE’s is converted nonlinear into ODE’s via applying suitable transformations. Computational solutions of the problem is also achieved via efficient numerical technique shooting. Characteristics of controlling parameters i.e. stretching index, inclined angle, Hartmann number, Weissenberg number, variable viscosity parameter, mixed convention parameter, Brownian motion parameter, Prandtl number, Lewis number, thermophoresis parameter and chemical reactive species on concentration, temperature and velocity gradient. Additionally, friction factor coefficient, Nusselt number and Sherwood number are describe with the help of graphics as well as tables verses flow controlling parameters. Keywords: Williamson nanofluid, Temperature depended viscosity, Inclined magnetic field, Mixed convection, Chemical reactive species, Variable viscosity, Shooting method

Variations in the biochemical structure of seven macroalgal species, belonging to different families were investigated along with subsequent analysis of relevant water physico-chemical parameters. Samples were collected from different sites along the Egyptian Qarun Lake during spring of 2017. The relationship between the macroalgal components and ambient water parameters was studied. The results indicated that the macroalgal components differed according to plant species and spatial variations. The green macroalgae species Ulva fasciata was recorded at site 5. It was found to have the highest protein (20.66 ± 0.04%), DCP (15.67 ± 0.04%), P/NFE (0.65 ± 0.01%), P/EV 7.65 ± 0.03 mg crude protein/K cal GE and nitrogen contents (3.31 ± 0.01%). However Cladophora laetevirens collected from site7, had the highest lipid, ME, EV and K contents (3.64 ± 0.00%, 3.25 ± 0.00%, 3.99 ± 0.00 K cal/g and 0.40 ± 0.0%, respectively). Mougeotia genuflexa from site 4, had the highest ash content (53.58 ± 0.08%). Gracilaria corticata from site 6, had the highest NFE and OM contents (76.26 ± 0.15 and 89.68 ± 0.04% respectively) and Enteromorpha intestinalis collected from site 2 had the highest P/L value (11.71 ± 0.02%). Statistical analysis (CCA) showed that some environmental variables such as temperature, NO3, pH, COD and transparency had a strong effect on the macroalgal components and were considered as the most important water variables. While others such as DO, SiO3, NO2 and PO4, exhibited a weak correlation. The present study demonstrates differential response of the macroalgal components to the environmental variables. In addition to the importance of these macroalgal species as a balanced artificial fish and animal feeds, particularly Ulva fasciata, which have the highest nutritional components. Keywords: Biochemical structure, Macroalgae, Water physicochemical parameters

Residential buildings consume a large amount of energy in operation, which can be reduced by planning energy-efficient design and operation strategies. Understanding and quantifying the impact of key driving factors to the residential building energy end-use is essential for promoting more energy-efficient building design and operation schemes. Although the climate, building, and occupant-related features have been proven as the key driving factors to residential building energy end-use, their impacts are rarely compared and quantified simultaneously. This study conducts the first attempt in combining the machine learning method with Monte Carlo method to quantify the impacts of these key driving factors simultaneously. Data collected from the Residential Energy Consumption Survey 2015 of the U.S. was investigated in this study. The results indicate that the total energy end-use has positive correlations with the total building area, rooms’ numbers, windows’ numbers, indoor heating temperature setpoint and the occupants’ age; and has a negative correlation with the cooling temperature setpoint; the impacts of heating degree days and cooling degree days are nonlinear and complicated; the impact of the level of insulation is nuanced and offset by the harsh climate. The results of this study contribute good references to policymakers and architects for the synthesis of energy-efficient residential building design and operation; guidelines can be developed for the future survey on residential building energy for relevant and precise data collection to improve the building energy modelling.

Here, biogenic synthesis of Fe2O3@SiO2 nanoparticles using fruit extract of Zanthoxylum rhetsa is reported. The SiO2 nanoparticles was synthesized using paddy straw which is a byproduct obtained in cultivation of rice. The composite was characterised by spectroscopic method like XRD, SEM, TEM and EDX analysis. The ipso-hydroxylation reactions were carried out with excellent yield within a moderate time period with mild reaction condition in all cases. Therefore, this approach may be considered as simple, easy, cheap and greener, environment friendly protocol for ipso-hydroxylation of arylboronic acids at 50 °C temperature.

Pure and fluorine highly doped Zinc oxide with different concentrations (0.1,0.2,0.3 mol/l) thin films were deposited on glass substrates heated up to 450 °C by chemical spray pyrolysis (CSP) technique. They were characterized using various techniques. X-ray diffraction pattern showed that all films had a polycrystalline structure Hexagonal wurtize phase; the doping processes did not show an obvious effect on the films structure. Structural parameters such as inter-planer distance, lattice constants, average grain size, dislocation density, the number of crystallites per unit surface area and strain could be determined as a function of Fluorine dopant concentration. The prepared films Grain size was found to be ranged from 39 to 52 nm, which indicates that all films have nanocrystalline structure. SEM images demonstrated a homogeneous and smooth uniform surface, and EDXS spectra confirm the stoichiometry of the deposited films . Optical properties data of the prepared films showed high transmittance values in the visible region (i.e. 40–99%), and this was increased after the doping process therefore the ZnO:F film was very suitable for solar cells applications . The energy gap (E g ) of direct electronic transitions was found equal to (3.082 eV) for pure ZnO and it increased to (3.163, 3.256, 3.271 eV) for ZnO:F, this behavior could be attributed to the Burstein–Moss effect.

Graphical abstractThe main goal of this paper is to investigate the effect of the multiple search operators with adaptive selection strategy and to develop hybrid version of non-dominated sorting genetic algorithm (HNSGA) for solving recently developed complicated multi-objective optimization test suit for multi-objective evolutionary algorithms (MOEAs) competition in the special session of the congress on evolutionary computing held at Norway in 2009 (CEC09). The Inverted generational distance (IGD) has been used performance indicator to establish valuable comparison between the suggested algorithm and NSGA-II as shown in the figure below. A set of Pareto optimal solutions with smaller is the IGD values confirm that approximated Pareto front (PF) will cover whole part of true PF in term of proximity and diversity. The average IGD-metric values evolution obtained by HNSGA versus NSGA-II for UF1-UF5 within allowable resources of 300,000 function evaluations. Display Omitted HighlightsA novel hybrid non-dominated sorting genetic algorithm (HNSGA) for multiobjective optimization with continuous variables is developed.HNSGA includes adaptive operator selection to allocate resources to multiple search operators based on their individual performance at the subpopulation level.HNSGA is tested in classical benchmark problems taken from the ZDT and CEC09 suites.Inverted generational distance (IGD), relative hypervolume (RHV), Gamma and Delta functions are used as performance indicators.The new algorithm is very competitive with other state-of-the-art optimizers such as AMALGAM, NSGA-II, MOEA/D, Hybrid AMGA, OMOEA, PA-DDS, etc. Multiobjective optimization entails minimizing or maximizing multiple objective functions subject to a set of constraints. Many real world applications can be formulated as multi-objective optimization problems (MOPs), which often involve multiple conflicting objectives to be optimized simultaneously. Recently, a number of multi-objective evolutionary algorithms (MOEAs) were developed suggested for these MOPs as they do not require problem specific information. They find a set of non-dominated solutions in a single run. The evolutionary process on which they are based, typically relies on a single genetic operator. Here, we suggest an algorithm which uses a basket of search operators. This is because it is never easy to choose the most suitable operator for a given problem. The novel hybrid non-dominated sorting genetic algorithm (HNSGA) introduced here in this paper and tested on the ZDT (Zitzler-Deb-Thiele) and CEC09 (2009 IEEE Conference on Evolutionary Computations) benchmark problems specifically formulated for MOEAs. Numerical results prove that the proposed algorithm is competitive with state-of-the-art MOEAs.

Crystal defects have been broadly regarded to modulate the photoreactivity of semiconductors, mostly concerning the crystal and electronic structure of materials. On the other hand, oxygen defect-engineering is a fundamental approach to improve the photolysis activity of materials. Herein, an interactive hybrid intermediate strategy with oxygen defect-engineering was utilized to fabricate atomically-thin Ti-doped Bi2MoO6 nanosheets. Experimental results unveil that the well-engineered ultrathin Ti-doped Bi2MoO6 nanosheets tune the morphology, visible light absorption, local atomic and electronic band structure of Bi2MoO6. Importantly, the Ti-doping hugely affects the BET specific surface area and porosity of Ti-Bi2MoO6 (72 m2 g−1) in contrast to bulk Bi2MoO6, which is 19 m2 g−1. Furthermore, the density functional theory calculations were carried out to explore the effect of Ti-doping on electronic band structure and the surface charge distribution in Ti-Bi2MoO6. It was found, rather than acting as a recombination center for photogenerated charge carriers, the defect caused by Ti doping mediated O vacancies in the crystal structure of Bi2MoO6, which favors the photogenerated charge carriers transfer and enhances the photocatalytic reactivity due to delocalized nature. With the advantages of atomically-thin structure Ti-Bi2MoO6 nanosheets, the synergistic effect of ultrathin thickness of Ti-Bi2MoO6 and oxygen vacancies has remarkably improved the photocatalytic activity towards the degradation of nitrofurantoin, and photoreduction of Cr(VI) in a highly acidic and alkaline medium. The present work opens a door for enhancing the photolysis performance of Bi2MoO6-based photocatalysts with excellent photolysis activity in the various environmental remediation processes.

Titanium dioxide (TiO2) was prepared using chemical spray pyrolysis technique on glass substrate at 350 °C with a spray rate of 5 s/1 min, for a thickness of 350 nm. The material characterization of the TiO2 nanofiber was performed using X-ray diffraction (XRD), scanning electronic microscopy (SEM), and atomic force microscopy (AFM). The optical absorption of the fibers was measured using a UV – vis spectrophotometer. The X-ray diffraction measurements confirmed that the films grown by this technique have good crystalline tetragonal anatase phase structure and with the preferred orientation along the [1 0 1] direction. The surface morphology of the TiO2 fibers showed that the micrography of the nanofiber are extra-fine. UV – vis transmittance measurements have shown that TiO2 fibers are highly transparent (∼90 (%in the visible wavelength region. The optical band gap of TiO2 fiber is 3.32 eV. The diameters of titanium dioxide nanotubes are found to be 30 – 60 nm, retaining the size and near cylindrical shape of the pores.

This article considers the entropy analysis of viscous nanofluid in an inclined ciliated tube with magnetic and Joule heating effects. The energy analysis is perfumed in the presence of internal heat source coefficient. The thermal conductivity of base fluid water is strengthen by considering the famous Tiwari–Das nanofluid model. Mathematical formulation have been operated which results into set of non-linear coupled partial differential equation. The governed differential system is transformed into ordinary differential system by considering the suitable similarity variables. Exact solutions in the closed form have been computed for the momentum, pressure gradient and temperature profiles. In this study, special attention is devoted to the term electrical conductivity of the considered copper nanoparticles. Graphical results shows that velocity of the fluid increases with an increment in the inclination angle and entropy of the fluid system increases with an increase in the nanoparticle concentration.