Exosomal miRNAs as a Promising Source of Biomarkers in Colorectal Cancer Progression

Colorectal cancer (CRC) is the third most common type of cancer worldwide amongst males and females. CRC treatment is multidisciplinary, often including surgery, chemotherapy, and radiotherapy. Early diagnosis of CRC can lead to treatment initiation at an earlier stage. Blood biomarkers are currently used to detect CRC, but because of their low sensitivity and specificity, they are considered inadequate diagnostic tools and are used mainly for following up patients for recurrence. It is necessary to detect novel, noninvasive, specific, and sensitive biomarkers for the screening and diagnosis of CRC at earlier stages. The tumor microenvironment (TME) has an essential role in tumorigenesis; for example, extracellular vesicles (EVs) such as exosomes can play a crucial role in communication between cancer cells and different components of TME, thereby inducing tumor progression. The importance of miRNAs that are sorted into exosomes has recently attracted scientists’ attention. Some unique sequences of miRNAs are favorably packaged into exosomes, and it has been illustrated that particular miRNAs can be directed into exosomes by special mechanisms that occur inside the cells. This review illustrates and discusses the sorted and transported exosomal miRNAs in the CRC microenvironment and their impact on CRC progression as well as their potential use as biomarkers.     

Effective incorporation of TiO2 nanoparticles into polyamide thin‐film composite membranes

The effectiveness of TiO₂ nanoparticles in improving the performance of polyamide (PA) thin‐film composite (TFC) membranes has been investigated. PA TFC membranes were prepared by interfacial polymerization with m‐phenylenediamine (MPD) and 1,3,5‐benzene tricarbonyl trichloride (TMC) where TiO₂ particles were added during and after interfacial polymerization. To distribute the TiO₂ nanoparticles uniformly in the PA films, colloidally stable TiO₂ sols were synthesized and added to the aqueous MPD solution rather than to an organic TMC solution. Through the use of different incorporation methods, TiO₂ particles were located on the top surface, in PA film layer, and in both positions. In the case of dense PA layers, the hydrophilicity of the membranes was significantly improved due to the presence of TiO₂ particles, resulting in an increased water flux. On the other hand, the enhancement of water flux was less significant when TiO₂ particles were incorporated into a loose PA film that was prepared with additives. In addition, a BSA fouling test confirmed that TiO₂ nanoparticles effectively improve the antifouling properties of the membranes for both dense and loose PA films. This effect is possibly due to increased hydrophilicity, covering of the fouling space, and a reduction in surface roughness. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43383.     

Research Progress on Properties and Applications of Polymer/Clay Nanocomposite

This review covers significant properties and applications of nanoclays in polymer-based nanocomposites with special emphasis on future potential. Various strategies have been adopted for nanocomposite synthesis including delamination of nanoclays through melt shearing, in situ polymerization, and sol–gel method. Proper dispersion of nanoclay results in improved properties of bulk polymer (thermal stability, mechanical strength, gas barrier, and flame retardancy). Light weight, low cost, and improved physical properties of polymer/clay materials increase their demand in modern material industries (aerospace, automobile, barrier materials, construction, and biomedical). Due to extensive use of these nanocomposites in technical fields, there are still many stones left unturned.     

Enhanced photocatalytic reduction of Cr(VI) on silver nanoparticles modified mesoporous silicon under visible light

The development of visible-light photocatalysts with desirable material characteristics and efficient performance is an existing challenge for photocatalysis community. Herein, we report on the synthesis of silver nanoparticles (AgNPs) modified porous silicon (PSi) nanopowder and its effective use in the photo-reduction of hexavalent chromium Cr(VI) to trivalent Cr(III) under direct visible light irradiation in the presence of citric acid. The PSi was prepared via simple stain etching of Si microparticles in HF/HNO₃ aqueous solution, followed by the deposition of AgNPs onto PSi by the immersion plating technique. The developed photocatalyst composed of PSi with <20 nm mesoporous structure, decorated with crystalline 15-50 nm AgNPs. Photocatalytic experiments using unmodified Si microparticles, either PSi or sonicated one, indicated inactive catalytic behavior toward the photo-reduction of Cr(VI). Remarkable photo-reduction efficiency (97.4%) was achieved after 180 minutes irradiation using the AgNPs/PSi sample. The efficient photo-reduction capability of AgNPs/PSi photocatalyst is attributed to the enhanced separation between photo-generated electrons and holes (e⁻-h⁺) enabling better utilization of light, as revealed from the photoluminescence measurement. Additionally, the presence of citric acid in solution promoted greatly the photo-reduction reaction as it acted as a hole scavenger, suppressing further the rate of e⁻-h⁺ recombination through rapid consumption of photo-generated holes. Excellent reusability of the current photocatalyst was evidenced by performing cyclic five runs with minimal reactivity loss. Results of synthesis, characterization, photocatalytic activity and reaction mechanism are thoroughly addressed and discussed.     

High capacity natural fiber coated conductive and electroactive composite papers electrode for energy storage applications

Flexible, lightweight, and environment friendly energy storage devices are in high demand of modern disposable technology. This study presents the coating of directly collected lignocelluloses fibers from self-growing plant, Monochoria vaginalis with conducting layers of polypyrrole and polyaniline. Fabricated paper electrodes were conductive, electroactive, all-organic constituents, flexible, and can be cut with help of scissor in any shape. Paper electrodes were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis for morphology, structural, and thermal characteristics, respectively. Furthermore, fabricated paper electrodes were characterized by cyclic voltammetry to confirm the electroactive behavior and showed excellent electrochemical performance. Paper sheets comprising lignocelluloses fibers and polypyrrole coating (LC/PPy) were employed as electrodes of symmetric cell and showed specific capacitance of 230.35 Fg⁻¹ at current density 0.25 mA g⁻¹ for LC/PANI, while LC/PPy showed 9.042 W h kg⁻¹ and 91.33 W kg⁻¹ energy density and power density, respectively. This paper electrodes are highly feasible for environmentally safe and flexible energy storage applications, particularly in era of modern disposable technology. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47282.     

The effect of nanosilica (SiO2) and nanoalumina (Al2O3) reinforced polyester nanocomposites on aerosol nanoparticle emissions into the environment during automated drilling

The aim of this study is to investigate the effect nanosilica and nanoalumina has on nanoparticle release from industrial nanocomposites due to drilling for hazard reduction whilst simultaneously obtaining the necessary mechanical performance. This study is therefore specifically designed such that all background noise is eliminated in the measurements range of 0.01 particles/cm³ and ±10% at 10⁶ particles/cm³. The impact nano-sized SiO₂ and Al₂O₃ reinforced polyester has on nanoparticle aerosols generated due to drilling is investigated. Real-time measurement was conducted within a specially designed controlled test chamber using a condensation particle counter (CPC) and a scanning mobility particle sizer spectrometer (SMPS). The results show that the polyester nanocomposite samples displayed statistically significant differences and an increase in nanoparticle number concentration by up to 228% compared to virgin polyester. It is shown that the nanofillers adhered to the polyester matrix showing a higher concentration of larger particles released (between 20 – 100 nm). The increase in nanoparticle reinforcement weight concentration and resulting nanoparticle release vary considerably between the nanosilica and nanoalumina samples due to the nanofillers presence. This study indicates a future opportunity to safer by design strategy that reduces number of particles released concentration and sizes without compromising desired mechanical properties for engineered polymers and composites.

© 2017 American Association for Aerosol Research     

Electro-spark coatings for enhanced performance of twist drills

Surface engineering approaches are being increasingly employed for enhancing the effective life of twist drills with a view to reduce machining costs. The electro-spark coating (ESC) technique provides a promising means of depositing wear resistant coatings that can potentially enhance the performance of these tools. However, it is often necessary to also optimize the machining conditions for coated tools to achieve an enhanced tool life. In the present investigation, varying spindle speeds were employed at a fixed vertical feed to evaluate the performance of WC-8Co ESC coated HSS drills in comparison to bare HSS drills. The number of holes drilled before reaching a preset average flank wear (0.5 mm), or catastrophic failure of the drill, was taken as the measure of tool life. The drill flank wear, monitored at regular intervals, as well as the cutting torque and thrust measured for all holes, were considered to be the key criteria for optimizing the cutting conditions. Results indicate that the WC-8Co coated drill tool life can be increased by a factor of more than 5, depending on the machining conditions selected. Furthermore, flank wear of the drill was found to increase rapidly at the end of drill life. Cutting torque data was also found to provide a useful indicator for predicting the end of tool life.     

Natural Convection Heat Transfer in an Enclosed Assembly of Thin Vertical Cylinders – A CFD Study

A thermal hydraulic study of convective heat transfer in 3 × 3 square array of heated vertical cylinders is carried out using computational fluid dynamics (CFD). Two different CFD approaches were used, i.e., full structural details (FSD) and porous media modeling (PMM). The computational requirement in PMM declined significantly due the porous media approximation. The PMM only gives the overall flow and temperature field. In the FSD model all the geometry details are presented without any approximation. The PMM and FSD results are compared to experimental data. In general, the prediction of temperature profiles from both PMM and FSD agreed well with the experimental data.     

Synthesis,stability and printing properties of a novel 2‐sulphophenoxy‐4‐chloro‐s‐triazine reactive dye for ink‐jet printing of wool

We report here the synthesis and characterisation of a new medium‐reactivity reactive dye containing 2‐sulphophenoxy‐4‐chloro‐s‐triazine, having enhanced the activity of the chlorine atom for further substitution by the functional groups carried by wool fibre. In addition, a dichloro‐s‐triazine dye was also synthesised for the purpose of comparison. The progress of synthesis reactions and purity of the dyes were determined using capillary electrophoresis and thin layer chromatography. The molecular structure and the chemical compositions of the synthesised dyes were confirmed using Fourier Transform–infrared spectral data and elemental analyses. The inks containing the synthesised dyes were formulated and ink‐jet‐printed onto wool fabrics and then the printed fabrics were steamed at 102°C. Compared with the dichloro‐s‐triazine dye, superior performance in terms of ink stability, K/S and dye fixation was observed for the new 2‐sulphophenoxy‐4‐chloro‐s‐triazine dye. In addition, the light fastness of the fabric printed with the inks containing the new dye was 0.5‐grade greater than that of the fabric printed with the inks containing the dichloro‐s‐triazine dye, and no changes in shade and staining were observed following wash fastness tests of the fabrics printed with the inks containing the new dye.     

Review and analysis of microbiologically influenced corrosion: the chemical environment in oil and gas facilities

Microbiologically influenced corrosion (MIC) is a complex phenomenon requiring integrated knowledge of multiple disciplines to better manage and mitigate impacts. The chemical environment (e.g. produced water, soured oil) plays an important role in MIC. Chemical reactions and phase changes due to temperature, pressure, pH and to a lesser extent salinity, impact microbial activities which in turn influences the surrounding chemical environment leading to corrosion. The chemical–microbial interactions complicate the understanding of chemical species transformation and partitioning behaviour in gas, water and oil and subsequent impact on corrosion. In this paper, a review of the complex chemical transformations of chemical species resulting from biotic and abiotic processes are presented. These chemical species can have growth, inhibitory or synergistic effects on microbial activities causing MIC. Microbial activities are found to overlap with chemical/electrochemical processes leading to corrosion. The interaction between chemical environment, environmental factors, electrochemical and microbial processes has been explained with examples from the literature, to understand the contributory effects on MIC. This study will inform further investigation on the chemical environment impacting MIC and model development.