Suspension plasma sprayed coatings using dilute hydrothermally produced titania feedstocks for photocatalytic applications

Titanium dioxide coatings have potential applications including photocatalysts for solar assisted hydrogen production, solar water disinfection and self-cleaning windows. Herein, we report the use of suspension plasma spraying (SPS) for the deposition of conformal titanium dioxide coatings. The process utilises a nanoparticle slurry of TiO2 (ca. 6 and 12 nm respectively) in water, which is fed into a high temperature plasma jet (ca. 7000-20 000 K). This facilitated the deposition of adherent coatings of nanostructured titanium dioxide with predominantly anatase crystal structure. In this study, suspensions of nano-titanium dioxide, made via continuous hydrothermal flow synthesis (CHFS), were used directly as a feedstock for the SPS process. Coatings were produced by varying the feedstock crystallite size, spray distance and plasma conditions. The coatings produced exhibited ca. 90-100% anatase phase content with the remainder being rutile (demonstrated by XRD). Phase distribution was homogenous throughout the coatings as determined by micro-Raman spectroscopy. The coatings had a granular surface, with a high specific surface area and consisted of densely packed agglomerates interspersed with some melted material. All of the coatings were shown to be photoactive by means of a sacrificial hydrogen evolution test under UV radiation and compared favourably with reported values for CVD coatings and compressed discs of P25.

Electroless nickel, alloy, composite and nano coatings - A critical review

The development of metal deposition processes based on electroless nickel, alloy and composite coatings on various surfaces has witnessed a surge in interest among researchers, with many recent applications made possible from many excellent properties. In recent years, these coatings have shown promising corrosion and wear resistance properties and large number of newer developments became most important from macro to nano level applications. After a brief review of the fundamental aspects underlying the coating processes, this paper discusses in detail about different electroless nickel alloy, composite, nano plating, bath techniques, preparation, characterization, new depositing mechanism and their recent applications, including brief notes on difficult substrate and waste treatment for green environment. Emphasis will be onto their recent progress, which will be discussed in detail and critically reviewed.

Oxidation-induced Cu coating on steel surface

Copper is accumulated in recycled steels and is difficult to be removed during steelmaking processes when steel scrap is used as steel sources. Meanwhile, copper characteristic properties are of importance both to human beings and to animals and plants. In this paper, integrated copper coating was observed on the surface of copper-containing steels when the steels were heated at around 1150°C. However, the copper was separately scattered after heating at 1000°C. The forming mechanisms of copper coating will be discussed in detail. By choosing proper descaling reagent, self-generated oxidation-induced copper coating appeared on the steel surface. The method proposed in this work is environmentally friendly for nontoxic chemicals being used. In addition, this provides a new concept for producing protective composite by oxidizing from the substrate directly and there is no binding problem.

Hydrogel antimicrobial capture coatings for endotracheal tubes; a pharmaceutical strategy designed to prevent ventilator-associated pneumonia.

This paper presents a novel strategy for the prevention of ventilator-associatedpneumonia that involves coating poly(vinyl chloride, PVC) endotracheal tubes (ET) withhydrogels that may be subsequently used to entrap nebulized antimicrobial solutions. Candidatehydrogels were prepared containing a range of ratios of hydroxyethyl methacrylate (HEMA) andmethacrylic acid (MAA) from 100:0 to 70:30 using free radical polymerization and, whenrequired, simultaneous attachment to PVC was performed. The mechanical properties, glasstransition temperatures, swelling kinetics, uptake of gentamicin from an aqueous medium, andgentamicin release were characterized. Increasing the MAA content of the hydrogels significantlydecreased the ultimate tensile strength, % elongation at break, Young’s modulus, and increasedthe glass transition temperature, the swelling ratio, and gentamicin uptake. Microbial(Staphylococcus aureus and Pseudomonas aeruginosa) adherence to control (drug-free) hydrogelswas observed; however, while adherence to gentamicin-containing p(HEMA) occurred, noadherence occurred to gentamicin-containing HEMA:MAA copolymers. Antimicrobialpersistence of gentamicin-containing hydrogels was examined by determining the zone ofinhibition against each microorganism on successive days. Hydrogel composition affected the observed antimicrobial persistence,with the hydrogel composed of 70:30 HEMA:MAA exhibiting >20 days persistence against S. aureus and P. aeruginosa,respectively. To simulate clinical use, the hydrogels (coated onto PVC) were first exposed to a nebulized solution of gentamicin(4 mL, 80 mg for 20 min), and then to nebulized bacteria (4 mL ca. 1 × 109 colony forming units mL−1, 30 min). Viable bacteriawere not observed on the gentamicin-treated p(HEMA: MAA) copolymers, whereas growth was observed on gentamicin-treatedp(HEMA). In light of the excellent antimicrobial activity and physicochemical properties, p(HEMA: MAA) copolymerscomposed of ratios of 80:20 or 70:30 HEMA: MAA were identified as potentially useful coatings of endotracheal tubes to be usedin conjunction with the clinical nebulization of gentamicin and designed for the prevention of ventilator-associated pneumonia

Formation of soluble mercury oxide coatings: transformation of elemental mercury in soils

The impact of mercury (Hg) on human and ecological health has been known for decades. Although a treaty signed in 2013 by 147 nations regulates future large-scale mercury emissions, legacy Hg contamination exists worldwide and small scale releases will continue. The fate of elemental mercury, Hg(0), lost to the subsurface and its potential chemical transformation that can lead to changes in speciation and mobility are poorly understood. Here we show that Hg(0) beads interact with soil or manganese oxide solids and x-ray spectroscopic analysis indicates that the soluble mercury coatings are HgO. Dissolution studies show that after reacting with a composite soil, > 20 times more Hg is released into water from the coated beads than from a pure liquid mercury bead. An even larger, > 700 times, release occurs from coated Hg(0) beads that have been reacted with manganese oxide, suggesting that manganese oxides are involved in the transformation of the Hg(0) beads and creation of the soluble mercury coatings. Although the coatings may inhibit Hg(0) evaporation, the high solubility of the coatings can enhance Hg(II) migration away from the Hg(0)-spill site and result in potential changes in mercury speciation in the soil and increased mercury mobility.

UAP1 is overexpressed in prostate cancer and is protective against inhibitors of N-linked glycosylation

Prostate cancer is the second most common cause of cancer-associated deaths in men, and signaling via a transcription factor called androgen receptor (AR) is an important driver of the disease. Consequently, AR target genes are prominent candidates to be specific for prostate cancer and also important for the survival of the cancer cells. Here we assess the levels of all hexosamine biosynthetic pathway (HBP) enzymes in 15 separate clinical gene expression data sets and identify the last enzyme in the pathway, UDP-N-acetylglucosamine pyrophosphorylase 1 (UAP1), to be highly overexpressed in prostate cancer. We analyzed 3261 prostate cancers on a tissue microarray and found that UAP1 staining correlates negatively with Gleason score (P=0.0039) and positively with high AR expression (P<0.0001). Cells with high UAP1 expression have 10-fold increased levels of the HBP end-product, UDP-N-acetylglucosamine (UDP-GlcNAc). UDP-GlcNAc is essential for N-linked glycosylation occurring in the endoplasmic reticulum (ER) and high UAP1 expression associates with resistance against inhibitors of N-linked glycosylation (tunicamycin and 2-deoxyglucose) but not with a general ER stress-inducing agent, the calcium ionophore A23187. Knockdown of UAP1 expression re-sensitized cells towards inhibitors of N-linked glycosylation, as measured by proliferation and activation of ER stress markers. Taken together, we have identified an enzyme, UAP1, which is highly overexpressed in prostate cancer and protects cancer cells from ER stress conferring a growth advantage.

Protective role of glycerol against benzene stress: insights from the Pseudomonas putida proteome

Chemical activities of hydrophobic substances can determine the windows of environmental conditions over which microbial systems function and the metabolic inhibition of microorganisms by benzene and other hydrophobes can, paradoxically, be reduced by compounds that protect against cellular water stress (Bhaganna et al. in Microb Biotechnol 3:701-716, 2010; Cray et al. in Curr Opin Biotechnol 33:228-259, 2015a). We hypothesized that this protective effect operates at the macromolecule structure-function level and is facilitated, in part at least, by genome-mediated adaptations. Based on proteome profiling of the soil bacterium Pseudomonas putida, we present evidence that (1) benzene induces a chaotrope-stress response, whereas (2) cells cultured in media supplemented with benzene plus glycerol were protected against chaotrope stress. Chaotrope-stress response proteins, such as those involved in lipid and compatible-solute metabolism and removal of reactive oxygen species, were increased by up to 15-fold in benzene-stressed cells relative to those of control cultures (no benzene added). By contrast, cells grown in the presence of benzene + glycerol, even though the latter grew more slowly, exhibited only a weak chaotrope-stress response. These findings provide evidence to support the hypothesis that hydrophobic substances induce a chaotropicity-mediated water stress, that cells respond via genome-mediated adaptations, and that glycerol protects the cell's macromolecular systems. We discuss the possibility of using compatible solutes to mitigate hydrocarbon-induced stresses in lignocellulosic biofuel fermentations and for industrial and environmental applications.

Effect of high pressure processing in combination with Weissella viridescens as a protective culture against Listeria monocytogenes in ready-to-eat salads of different pH

This study explored the effect of HPP (400 MPa/1 min) and a Weissella viridescens protective culture, alone or in conjunction, against Listeria monocytogenes in ready-to-eat (RTE) salads with different pH values (4.32 and 5.59) during storage at 4 and 12 °C. HPP was able to reduce the counts of the pathogen after treatment achieving approximately a 4.0 and 1.5 log CFU/g reduction in the low and higher pH RTE salad, respectively. However, L. monocytogenes was able to recover and grow during subsequent storage. W. viridescens grew in both RTE salads at both storage temperatures, with HPP resulting in only a small immediate reduction of W. viridescens ranging from 0.50 to 1.2 log CFU/g depending on the pH of the RTE salad. For the lower pH RTE salad, the protective culture was able to gradually reduce the L. monocytogenes counts during storage whereas for the higher pH RTE salad in some cases it delayed growth significantly or exerted a bacteriostatic effect. exerted a bacteriostatic effect. The results revealed that the increased storage temperature led to an increase in the inactivation/inhibition of L. monocytogenes in the presence of W. viridescens. The combination of HPP and W. viridescens is a promising strategy to control L. monocytogenes and can increase safety even when a break in the chill chain occurs.

Effect of reinforcement and heat treatment on elevated temperature sliding of electroless Ni–P/SiC composite coatings

The investigation is focused on the wear behaviour at elevated test temperature of composite Ni–P/SiC deposit, with varying concentration of the reinforcing SiC particles. The phase evolution measured by X-ray diffraction suggests slight crystallisation during wear testing at 200 °C. In coating without reinforcing particles, adhesive wear is accompanied by microcracks. The thermal heat generated and the cyclic loading could have induced sub-surface microcracks. Owing to the effective matrix-ceramics system in composite coatings, fine grooves, abrasive polishing and uniform wearing are observed. Reinforcing particles in the matrix hinder microcrack formation and significantly reduce the wear rate. Triboxidation is confirmed from energy dispersive X-ray spectrometry.

Metabolically-inactive glucagon-like peptide-1(9-36)amide confers selective protective actions against post-myocardial infarction remodelling

BACKGROUND: Glucagon-like peptide-1 (GLP-1) therapies are routinely used for glycaemic control in diabetes and their emerging cardiovascular actions have been a major recent research focus. In addition to GLP-1 receptor activation, the metabolically-inactive breakdown product, GLP-1(9-36)amide, also appears to exert notable cardiovascular effects, including protection against acute cardiac ischaemia. Here, we specifically studied the influence of GLP-1(9-36)amide on chronic post-myocardial infarction (MI) remodelling, which is a major driver of heart failure progression.

METHODS: Adult female C57BL/6 J mice were subjected to permanent coronary artery ligation or sham surgery prior to continuous infusion with GLP-1(9-36)amide or vehicle control for 4 weeks.

RESULTS: Infarct size was similar between groups with no effect of GLP-1(9-36)amide on MI-induced cardiac hypertrophy, although modest reduction of in vitro phenylephrine-induced H9c2 cardiomyoblast hypertrophy was observed. Whilst echocardiographic systolic dysfunction post-MI remained unchanged, diastolic dysfunction (decreased mitral valve E/A ratio, increased E wave deceleration rate) was improved by GLP-1(9-36)amide treatment. This was associated with modulation of genes related to extracellular matrix turnover (MMP-2, MMP-9, TIMP-2), although interstitial fibrosis and pro-fibrotic gene expression were unaltered by GLP-1(9-36)amide. Cardiac macrophage infiltration was also reduced by GLP-1(9-36)amide together with pro-inflammatory cytokine expression (IL-1β, IL-6, MCP-1), whilst in vitro studies using RAW264.7 macrophages revealed global potentiation of basal pro-inflammatory and tissue protective cytokines (e.g. IL-1β, TNF-α, IL-10, Fizz1) in the presence of GLP-1(9-36)amide versus exendin-4.

CONCLUSIONS: These data suggest that GLP-1(9-36)amide confers selective protection against post-MI remodelling via preferential preservation of diastolic function, most likely due to modulation of infiltrating macrophages, indicating that this often overlooked GLP-1 breakdown product may exert significant actions in this setting which should be considered in the context of GLP-1 therapy in patients with cardiovascular disease.

TELL ME Design: Protective Behaviour During an Epidemic

The TELL ME agent based model simulates the connections between health agency communication, personal decisions to adopt protective behaviour during an influenza epidemic, and the effect of those decisions on epidemic progress. The behaviour decisions are modelled with a combination of personal attitude, behaviour adoption by neighbours, and the local recent incidence of influenza. This paper sets out and justifies the model design, including how these decision factors have been operationalised. By exploring the effects of different communication strategies, the model is intended to assist health authorities with their influenza epidemic communication plans. It can both assist users to understand the complex interactions between communication, personal behaviour and epidemic progress, and guide future data collection to improve communication planning.