Super‐resolution microscopy by movable thin‐films with embedded microspheres: Resolution analysis

Microsphere‐assisted imaging has emerged as an extraordinary simple technique of obtaining optical super‐resolution. This work addresses two central problems in developing this technology: i) methodology of the resolution measurements and ii) limited field‐of‐view provided by each sphere. It is suggested that a standard method of resolution analysis in far‐field microscopy based on convolution with the point‐spread function can be extended into the super‐resolution area. This allows developing a unified approach to resolution measurements, which can be used for comparing results obtained by different techniques. To develop the surface scanning functionality, the high‐index (n ～ 2) barium titanate glass microspheres were embedded in polydimethylsiloxane (PDMS) thin‐films. It is shown that such films adhere to the surface of nanoplasmonic structures so that the tips of embedded spheres experience the objects’ optical near‐fields. Based on rigorous criteria, the resolution ～λ/6‐λ/7 (where λ is the illumination wavelength) is demonstrated for arrays of Au dimers and bowties. Such films can be translated along the surface of investigated samples after liquid lubrication. It is shown that just after lubrication the resolution is diffraction limited, however the super‐resolution gradually recovers as the lubricant evaporates.

     

Numerical investigation of mixed convection heat transfer behavior of nanofluid in a cavity with different heat transfer areas

Journal of Thermal Analysis and Calorimetry - The main purpose of this research is the numerical modeling of laminar mixed convection heat transfer inside an open square cavity with different heat...     

MicroRNA‐2861 and nanofibrous scaffold synergistically promote human induced pluripotent stem cells osteogenic differentiation

Tissue engineering using new strategies has become a growing and promising method for treating large tissue lesions in the body. On the other hand, microRNAs (miRNAs), which are small non‐coding regulatory RNAs, are a new class of genetic materials that can have effective pharmacological roles. The combination of these two themes has created promising prospects for the treatment of diseases. Herein, human induced pluripotent stem cells (iPSCs) were transduced with miRNA‐2861 and then the osteogenic differentiation potential of transduced iPSCs and non‐transduced iPSCs was investigated while cultured on the electrospun poly lactic‐co‐glycolic acid (PLGA) nanofibrous scaffold and culture plate. MiR‐2861‐transduced iPSCs showed a significantly higher viability, mineralization, alkaline phosphatase (ALP) activity, calcium content, and bone‐related gene expression in comparison with those iPSCs that non‐transduced. The results also indicated that this increase is improved when miR‐2861 transduced iPSCs are cultured on the PLGA nanofibrous scaffold synergistically. This synergy was also confirmed by the results obtained from of Western blot analysis. It can be concluded that, miR‐2861, by negative regulation of those proteins that decrease/inhibit osteogenic differentiation and PLGA nanofibrous scaffold by preparation of a suitable artificial extracellular matrix, have a great positive impact in improving iPSCs osteogenic differentiation potential and this blend can be proposed to use in bone tissue engineering application.     

Phosphorus‐containing polyamide Mg(OH)2 nanocomposite coating on surface of poly(vinyl chloride) thin film: Study on thermal stability,flammability, and mechanical properties

Surface of poly(vinyl chloride) (PVC) thin films was coated using DOPO‐based polyamide (DBPA) coating and DBPA/Mg(OH)₂ nanocomposites (DBPN) coating by dip‐coating process. For this purpose, a new DOPO‐based dicarboxylic acid (DBDA) was synthesized and used for preparation of DBPA and organically surface modification of Mg(OH)₂ nanoparticles. The effects of DBPA and DBPN coatings on the morphology, thermal stability, combustion, and mechanical properties of PVC were investigated. The uniform dispersion of Mg(OH)₂ nanoparticles (nano‐MDH) and organically coating manner on the surface of the PVC films were confirmed by ATR‐IR spectroscopy, X‐ray diffraction (XRD), field emission scanning electron microscopy (FE‐SEM), energy dispersive X‐ray, and elemental mapping. From thermal gravimetry analysis (TGA) results, the 10 mass% loss temperature (T₁₀) increased from 268°C to 272°C in PVC coated with DBPA‐containing 10 mass% of modified Mg(OH)₂ (MMH). Also the char residue, first and second mass loss temperatures of all PVC coated were increased compared with the neat PVC film. According to microscale combustion calorimetry (MCC) results, the peak of heat release rate (pHHR) and total heat release (THR) were decreased from 128 ± 2 to 69 W/g and 12 ± 1 to 4 ± 2 KJ/g for PVC film coated with DBPA‐containing 10 mass% of MMH, compared with the neat PVC. From tensile test results, tensile strength was increased from 31.78 ± 0.8 to 39.64 ± 0.9 MPa for PVC coated with polyamide‐containing 5 mass% of MMH compared with the neat PVC.     

Surveying FDA-approved drugs as new potential inhibitors of N-cadherin protein: a virtual screening approach

Since N-cadherin protein plays a remarkable role in cancer metastasis and tumor growth and progression, finding new effective inhibitors of this protein can be of high importance in cancer treatment. Nevertheless, few molecules have been introduced to inhibit N-cadherin protein to date. In this work, in order to find and present potent inhibitors, 3358 FDA-approved small molecules were docked against N-cadherin protein. All complexes with binding energy ??9 to ??8 kcal/mol were selected for protein-ligand interaction analysis. In the following, Tanimoto coefficient (T_c) was calculated for those molecules that established appropriate interactions with N-cadherin in order to compute the similarity score between them. Afterwards, molecular dynamics simulation and free energy calculations were done to estimate the stability and ability of the chosen ligands in complex with the target protein. Finally, seven small molecules among 3358 FDA-approved were suggested as potential inhibitors of N-cadherin protein.

     

‘Click Synthesis’ of 1H‐1,2,3‐Triazolyl‐Based Oxiconazole (=(1Z)‐1‐(2,4‐Dichlorophenyl)‐2‐(1H‐imidazol‐1‐yl)ethanone O‐[(2,4‐Dichlorophenyl)methyl]oxime) Analogs

The ‘click synthesis’ of some oxiconazole analogs 5a – 5v having 1H‐1,2,3‐triazolyl residues by Huisgen cycloaddition was achieved in four steps (Scheme 1). Oximation of phenacyl chloride ( 1 ) followed by azidation of 2‐chloro‐1‐phenylethanone oxime ( 2 ) provided azido ketoxime 3 . The CuI‐catalyzed Huisgen cycloaddition of 3 with terminal alkynes gave the 4‐substituted (at the triazole) 2‐(1H‐1,2,3‐triazol‐1‐yl)‐1‐phenylethanone oximes 4a – 4i . The O‐alkylation of 4a – 4i with various alkyl halides resulted in the formation of the target molecules 5a – 5v in good yields.     

Surface Patterning Increases Fluid Sorption Efficiency in Porous Reactive Coatings: A Model for Optimised Surface-Flow Filtration

Transport in Porous Media - A novel surface-flow filter has been designed to take advantage of a combination of both diffusion and lateral flow permeation, since active coatings, even if porous,...     

Copper-doped silica cuprous sulfate (CDSCS) as a highly efficient and new heterogeneous nano catalyst for [3+2] Huisgen cycloaddition

The synthesis and characterization of copper-doped silica cuprous sulfate (CDSCS) as a new and efficient heterogeneous nano catalyst are described. CDSCS has been fully characterized by different microscopic, spectroscopic and physical techniques, including scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic forced microscopy (AFM), X-ray diffraction (XRD), inductively coupled plasma (ICP) analysis, thermogravimetric analysis (TGA) and FT-IR. CDSCS is proved to be a useful heterogeneous nano catalyst in Cu(I)-catalyzed ‘Click’ cycloaddition of organic azides with terminal alkynes. CDSCS catalyzes the 1,3-dipolar cycloaddition reactions of β-azido alcohols and alkynes at room temperature, in THF/H₂O (1:1, v/v) solution. Using CDSCS, 1,4-disubstituted 1,2,3-triazole adducts are mainly obtained, in good to excellent yields and in short reaction times. These compounds have featural resemblance to β-adrenoceptor blocking agents. CDSCS was approved as a chemically and thermally stable nano catalyst that can be reused for many consecutive trials without a significant decline in its reactivity.     

Adaptive fuzzy sliding mode control scheme for uncertain systems

Most physical systems inherently contain nonlinearities which are commonly unknown to the system designer. Therefore, in modeling and analysis of such dynamic systems, one needs to handle unknown nonlinearities and/or uncertain parameters. This paper proposes a new adaptive tracking fuzzy sliding mode controller for a class of nonlinear systems in the presence of uncertainties and external disturbances. The main contribution of the proposed method is that the structure of the controlled system is partially unknown and does not require the bounds of uncertainty and disturbance of the system to be known; meanwhile, the chattering phenomenon that frequently appears in the conventional variable structure systems is also eliminated without deteriorating the system robustness. The performance of the proposed approach is evaluated for two well-known benchmark problems. The simulation results illustrate the effectiveness of our proposed controller.