Adaptive Fuzzy SMC-Based Formation Design for Swarm of Unknown Time-Delayed Robots

In this paper, a multi-robot formation control is designed based on Sliding Mode Control (SMC) technique. Although the structure and sensing capabilities of each robot are very simple, complex formation behaviors emerge from cooperation among them. We use an adaptive fuzzy approximator, in which unknown dynamic of robots and time delays are approximated precisely. Then it is shown that autonomous robots are able to form geometrical formations, even in the case of time-delayed dynamics, and presence of obstacles. Various simulation results and comparisons with existing works are provided that demonstrate performing efficient formation of unknown robots, with robust characteristics.     

Chemical diversity of the essential oils of twenty populations of Tanacetum polycephalum Sch. Bip. from Iran

Chemical diversity of the essential oils of twenty wild populations of Tanacetum polycephalum Sch. Bip., was investigated. The aerial parts of T. polycephalum were collected at full flowering stage from West Azerbaijan Province of Iran, air-dried; hydrodistilled to produce essential oils. The essential oils were analyzed by GC-FID and GC-MS. A total of forty compounds were identified accounting for 96.4–99.9% of the total oils. The most principal compounds were cis-thujone (0–82.3%), trans-thujone (0–79.8%), camphor (1.3–75.0%), 1,8-cineole (4.5–43.3%), borneol (1.0–36.2%) and bornyl acetate (0–26.8%). Hierarchical cluster analysis based on the percentages (>0.5%) of the essential oils components was carried out to determine the chemical diversity among the populations studied. The cluster analysis resulted in the identification of four main chemotypes namely: ‘camphor + 1,8-cineole’, ‘mixed’, ‘cis-thujone’ and ‘trans-thujone’.     

Development of high performance nano-porous polyethersulfone ultrafiltration membranes with hydrophilic surface and superior antifouling properties

Hydrophilic nano-porous polyethersulfone ultrafiltration membranes were developed for milk concentration. The membranes were prepared from new dope solution containing polyethersulfone (PES)/polyvinylpirrolidone (PVP)/polyethyleneglycole (PEG)/cellulose acetate phthalate (CAP)/acrylic acid/Triton X-100 using phase inversion induced by immersion precipitation technique. This casting solution leads to formation of new hydrophilic membranes. The morphological studies were investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). In addition, the hydrophilicity and performance of membranes were examined by contact angel measurements and cross-flow filtration (pure water flux, milk water permeation, protein rejection and antifouling measurements). The contact angle measurements indicate that a surface with superior hydrophilicity was obtained for PES membranes. Two concentrations of PES (16 and 14.4 wt.%) and two different non-solvents (pure water and mixtures of water and IPA) were used for preparation of membranes. The morphological studies showed that the higher concentration of PES and the presence of IPA in the gelation media results in formation of a membrane with a dense top and sub-layer with small pores on the surface. The pure water flux of membranes was decreased when higher polymer concentration and mixtures of water and IPA were employed for membrane formation. On the other hand, the milk water permeation and protein rejection were increased using mixtures of water and IPA as non-solvent. Furthermore, the fouling analysis of the membranes demonstrated that the membrane surface with fewer tendencies for fouling was obtained.     

Dynamic viscoelastic effects on sound wave scattering by an eccentric compound circular cylinder

The classical method of separation of variables in conjunction with the translational addition theorem for cylindrical wave functions are employed to obtain an exact solution for two-dimensional interaction of a harmonic plane acoustic wave with an infinitely long (visco)elastic circular cylinder which is eccentrically coated by another (visco)elastic material and is submerged in an ideal unbounded acoustic medium. The novel features of Havriliak-Negami model for dynamic viscoelastic material behaviour are used to take the rheological properties of the coating (and/or core) material into consideration. The analytical results are illustrated with numerical examples in which a steel rod eccentrically coated with (an eccentric steel shell filled with) dissipative materials of distinct viscoelastic properties is insonified by plane sound waves at selected angles of incidence. The effects of incident wave frequency, angle of incidence, core eccentricity and dynamic viscoelastic material properties on the backscattered form function spectra are examined. Limiting cases are considered and fair agreements with available solutions are obtained.     

Real-time, high velocity-resolution color Doppler optical coherence tomography

Color Doppler optical coherence tomography (CDOCT) is a noninvasive optical imaging technique for micrometer-scale physiological flow mapping simultaneously with morphological optical coherence tomography imaging. We have developed a novel CDOCT signal-processing strategy capable of imaging physiological flow rates at 8 frames/s. Our new strategy features hardware-implemented digital autocorrelation across subsequent scans, permitting us to measure 300-Hz-8-kHz Doppler shifts upon signals of 0.6-MHz bandwidth. The performance of the CDOCT system was demonstrated in a flow phantom and in vivo in Xenopus laevis.     

Self-referenced Doppler optical coherence tomography

Doppler optical coherence tomography (DOCT) allows simultaneous micrometer-scale resolution cross-sectional imaging of tissue structure and blood flow. We demonstrate a fiber-optic polarization-diversity-based differential phase contrast DOCT system as a method to perform self-referenced velocimetry in highly scattering media. Using this strategy, we reduced common-mode interferometer noise to <1 Hz and improved Doppler estimates in a scattering flow phantom by a factor of 5.     

Cu immobilized on chitosan-modified iron oxide magnetic nanoparticles: Preparation,characterization and investigation of its anti-lung cancer effects

Chitosan is a linear polysaccharide and non-toxic bioactive polymer with a wide variety of applications due to its functional properties such as ease of modification, and biodegradability. In this study, a green protocol for supporting of Cu(II) on chitosan-encapsulated magnetic Fe₃O₄ nanoparticles is described. The morphological and physicochemical features of the material were determined using several advanced techniques like fourier transformed infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), inductively coupled plasma (ICP), vibrating sample magnetometer (VSM) and X-ray photoelectron spectroscopy (XPS). The average diameter of the NPs was approximately 15–25 nm. In addition, the Fe₃O_/CS/Cu(II) nanocomposite was engaged in biological assays like study of anti-oxidant properties by DPPH mediated free radical scavenging test using BHT as a reference molecule. Thereafter, on having a significant IC₅₀ value in radical scavenging assay, we extended the bio-application of the desired nanocomposite in anticancer study of lung well-differentiated bronchogenic adenocarcinoma, lung moderately differentiated adenocarcinoma, and lung poorly differentiated adenocarcinoma of human lung in-vitro conditions. In the cytotoxicity and anti-human lung studies, the nanocomposite was treated to lung cancer lung well-differentiated bronchogenic adenocarcinoma (HLC-1), lung moderately differentiated adenocarcinoma (LC-2/ad), and lung poorly differentiated adenocarcinoma (PC-14) cell line following MTT assay. The cell viability of malignant lung cell line reduced dose-dependently in the presence of Fe₃O_/CS/Cu(II) nanocomposite. The recent results suggest that Fe₃O_/CS/Cu(II) nanocomposite have a suitable anticancer activity against lung cell lines.     

Design of potential anti-tumor PARP-1 inhibitors by QSAR and molecular modeling studies

Molecular Diversity - Poly ADP-ribose polymerase-1 (PARP-1) inhibitors have been recognized as new agents for the treatment of patients with breast cancer type 1 (BRCA1) disorders. The quantitative...     

Rapid and Direct Spectrofluorometric and Chemometrics Methods for the Simultaneous Determination of Two Dansyl Derivatives

ABSTRACT

In this study the simultaneous molecular spectrofluorometric determination of ultratrace amounts of two dansyl chloride derivatives, DMNPS (5-(dimethylamino)naphthalene-1-sulfonyl 4-phenylsemicarbazide) and DMNPH (2-(5-(dimethylamino)naphthalen-1-ylsulfonyl)-N-phenylhydrazinecarbothioamide), was accomplished using a genetic algorithm joint partial least squares (GA-PLS) technique that leads to very low detection limits (lower than 10^?6 mol/L) The linear dynamic ranges of the compounds were 1–6 µ mol L^?1 and 1–7 µ mol L^?1 for DMNPS and DMNPH, respectively. Quantification was performed using the emission wavelength range from 360 to 600 nm with an optimum calibration sample number of 25 and prediction sample number of 7. The technique was proved to be beneficial.