Copper-Decorated Titanium Electrodes: Impact of Surface Modifications of Substrate on the Morphology and Electrochemical Performance

This study investigates the effect of surface modifications of the titanium substrate on the growth of electrochemically deposited copper. These materials are intended to serve as cathodes in the electroreduction of nitrates in aqueous solutions. Surface modifications included the use of hydrogen fluoride for titanium etching and anodization to promote the growth of a structured titania nanotube array. The effect of an intermediate calcination step for the nanotubes before deposition was assessed along with a comparison to an untreated substrate electrode. The materials were comprehensively characterized by SEM, XRD, contact angle, potentiodynamic tests, EIS, and cyclic voltammetry. Their electrocatalytic ability was tested in the reduction of aqueous solutions containing nitrates. The results reveal that surface finishing impacted the shape and size of the Cu microparticles, as well as the nucleation mechanism enabling a crystal-facet-controllable synthesis. All the materials exhibited microsized copper particles with a spherical shape with some clusters. On the etched titanium surface, a high number of heterogeneous submicroscopic particles were also present. The thermally treated anodized substrate promoted the development of a combination of sparse microparticles corresponding to defect sites in amorphous titanium and the presence of a diffuse coating of octahedral nanosized particles whose growth was promoted by the tetragonal structure of anatase crystals. Electrochemical tests display reduced charge transfer resistance upon copper deposition on the modified substrates, which is indicative of the enhanced conductivity of the coated materials. Additionally, cyclic voltammetry and electrolysis experiments reveal the electrodes' potential for nitrate reduction, showing a better response for the etched titanium substrate (30% nitrate removal, after 2 h at 25 mA cm-2).

Facile and Bioinspired Approach from Gallic Acid for the Synthesis of Biobased Flame Retardant Coatings of Basalt Fibers

A sustainable, bioinspired approach to functionalize basalt fibers with an innovative gallic acid (GA)-iron phenyl phosphonate complex (BF-GA-FeP), for the purpose of improving the flame retardancy in composite materials, is developed. BFs were at first pretreated with O3, obtaining surface free hydroxyl groups that allowed the subsequent covalent immobilization of biosourced GA units on the fiber through ester linkages. Phenolic -OH groups of the GA units were then exploited for the complexation of iron phenyl phosphonate, resulting in the target-complex-coated BF fiber (BF-GA-FeP). Microwave plasma atomic emission spectroscopy and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy analyses of BF-GA-FeP highlighted an increase in iron content, modification of fiber morphology, and occurrence of phosphorus, respectively. BFs, modified with a low amount of the developed complex, were used to reinforce a poly(lactic acid) (PLA) matrix in the production of a biocomposite (PLA/BF-FeP). PLA/BF-FeP showed a higher thermal stability than neat PLA and PLA reinforced with untreated BFs (PLA/BF), as confirmed by thermogravimetric analysis. The cone calorimeter test highlighted several advantages for PLA/BF-FeP, including a prolonged time to ignition, a reduced time to flame out, an 8% decrease in the peak heat release rate, and a 15% reduced fire propagating index compared to PLA/BF.

Stigmatizing attitudes toward Internet gaming disorder, Problematic smartphone use and Problematic social networking site use: An experimental vignette study

Public stigma on substance and gambling disorders have been well documented. Negative effects of stigma include shame, embarrassment, fear being judged and the determent of help-seeking behaviors among stigmatized individuals. Less is known about the public perception toward Internet gaming disorder (IGD) and other widespread problematic behaviors that share some characteristics with established behavioral addictions, such as Problematic smartphone use (PSU) and Problematic social networking sites use (PSNSU). The purpose of this study is to compare the public perception of problematic Internet gamers, problematic smartphone users and problematic social networking sites users using an experimental within-group vignette study design. A sample of 280 adults (F = 72.1%; M_age = 32.84, SD = 13.85) was recruited and completed the study online. Participants were presented with male OR female vignettes (i.e. the gender of the target in the vignette was randomized) describing an individual with IGD, PSU, and PSNSU. A repeated-measures ANOVA followed by post hoc tests using Bonferroni's correction was used. IGD was seen as more serious, more noticeable, and less understandable than both PSU and PSNU. Moreover, participants' emotional reaction (e.g., anger and sadness) and desired social distance were significantly stronger toward IGD. However, vanity attributions were higher for individuals with PSNSU, which were also more blamed compared to both IGD and PSU. PSU was seen as more controllable than both IGD and PSNSU. The results, taken together, suggest that IGD is perceived as more inherently problematic, but PSNSU also seem to deserve scientific attention as individuals showing symptoms of PSNSU are blamed more than problematic Internet gamers. Our findings provide initial information that can be used when developing interventions to impact stigma toward technological addictions.

Effect of Precursors on the Electrochemical Properties of Mixed RuOx/MnOx Electrodes Prepared by Thermal Decomposition

Growing thin layers of mixed-metal oxides on titanium supports allows for the preparation of versatile electrodes that can be used in many applications. In this work, electrodes coated with thin films of ruthenium (RuOx) and manganese oxide (MnOx) were fabricated via thermal decomposition of a precursor solution deposited on a titanium substrate by spin coating. In particular, we combined different Ru and Mn precursors, either organic or inorganic, and investigated their influence on the morphology and electrochemical properties of the materials. The tested salts were: Ruthenium(III) acetylacetonate (Ru(acac)₃), Ruthenium(III) chloride (RuCl₃·xH₂O), Manganese(II) nitrate (Mn(NO₃)₂·4H₂O), and Manganese(III) acetylacetonate (Mn(acac)₃). After fabrication, the films were subjected to different characterization techniques, including scanning electron microscopy (SEM), polarization analysis, open-circuit potential (OCP) measurements, electrochemical impedance spectroscopy (EIS), linear sweep voltammetry (LSV), cyclic voltammetry (CV), and galvanostatic charge-discharge (GCD) experiments. The results indicate that compared to the others, the combination of RuCl₃ and Mn(acac) produces fewer compact films, which are more susceptible to corrosion, but have outstanding capacitive properties. In particular, this sample exhibits a capacitance of 8.3 mF cm^-2 and a coulombic efficiency of higher than 90% in the entire range of investigated current densities.

Pyrolysis wastewater treatment by adsorption on biochars produced by poplar biomass

Pyrolysis is a widely studied thermochemical process, however the disposal of the produced byproducts is an unexplored field. In particular, the acqueous phase, characterized by a high organic load (TOC), must be necessarily treated. Aims of this work is to study the potentiality of biochar as adsorbent material for the treatment of this wastewater. For this aim, pyrolysis wastewater and biochar produced in the same plant were used. Two biochars produced at different temperatures (550 and 750 °C) and an activated biochar produced by chemical activation with NaOH of the raw biomass were tested. The study shows that higher temperature in the biochar production leads to higher sorption capacity of the organic compounds due to an increase of the surface area. The activation process further increases the surface area of the biochar that becomes similar to that of a commercial activated carbon while the sorption capacity exceeds that of commercial activated carbon of 2.5 times.

Tetrachloroethene recovery and hazard reduction of spent powders from dry cleaning process

Dry cleaning facilities using perchloroethylene produce a solid waste consisting of spent filtering powders with a high content of residual perchloroethylene, together with dyes and non-volatile residues. Untreated spent powders, classified as hazardous waste, cannot be disposed in landfill and incineration represents the only viable alternative. In this study, together with a full characterisation of the waste, the removal and recovery of the residual perchloroethylene by means of different heat treatments was investigated. In particular, tests of distillation and stripping with air and steam were carried out, evaluating the effectiveness of the treatments by quantifying the residual perchloroethylene in the samples treated. The results obtained show that the spent filtering powders contained about 25% wt. of perchloroethylene and that the maximum perchloroethylene recovery was obtained by steam stripping; approximately 98% after only 50 minutes. However, this treatment accounted for the production of a liquid mixture containing perchloroethylene and of a solid waste that required a further washing with boiling water to decrease the residual organic content below the eligibility criteria for landfill disposal.

Environmental effects of using chelating agents in polluted sediment remediation

The results of laboratory scale experimental tests of contaminant extraction from marine sediment slurries are presented and discussed. The objective of this study was to compare the effectiveness of EDTA and rhamnolipid in copper removal from an artificially contaminated sediment. The comparison was made in terms of metal extraction yield, and in the evaluation of its mobilization towards the more exchangeable fractions in the sediment. Results show that, under acidic conditions established during washing, EDTA ensured higher extractions efficiencies of Cu (up to 95 %) than rhamnolipid, although there was less mobilization into bioavailable forms with the use of rhamnolipid. In addition, in the view of a biological treatment of the spent solution, the use of rhamnolipid resulted in a lower decrease of the specific oxygen uptake rate with respect to EDTA. In fact, the low surfactants concentration required, partially compensated the toxic effect of Cu towards biomass.

Transversus abdominis plane block for analgesia after Cesarean delivery. A systematic review

Cesarean delivery is a major surgical procedure, after which a woman can experience substantial postoperative discomfort or pain. Inadequate postoperative analgesia is one of the most common reasons for poor patient satisfaction following cesarean delivery. Although spinal or systemic opioids are currently the gold standard to achieve effective analgesia, they are often associated with side effects. In the last few years there has been growing interest in abdominal plane blocks, with promising data on their efficacy. The transversus abdominis plane (TAP) block is a regional analgesic technique which is gaining acceptance in postoperative analgesia for lower abdominal surgeries. In this systematic review of articles published as of 31 December 2013, we searched the principal medical databases for randomized controlled trials that assessed the efficacy of ultrasound (US)-guided TAP block following cesarean delivery and reported on postoperative opioid consumption and pain score, opioid-related side-effects and patient satisfaction. Although controversy surrounds the utility of US-guided TAP block in cesarean section, evidence suggests that when correctly executed as part of a multimodal analgesic regimen, TAP block may reduce postoperative opioid consumption and opioid-related side effects, improving postoperative pain control and patient satisfaction. Further studies are necessary to explore this field of research.

Hexavalent chromium reduction in contaminated soil: A comparison between ferrous sulphate and nanoscale zero-valent iron

Iron sulphate (FeSO4) and colloidal nano zero-valent iron (nZVI) as reducing agents were compared, with the aim of assessing their effectiveness in hexavalent chromium [Cr(VI)] removal from a contaminated industrial soil. Experiments were performed on soil samples collected from an industrial site where a nickel contamination, caused by a long-term productive activity, was also verified. The influence of reducing agents amount with respect to chromium content and the effectiveness of deoxygenation of the slurry were discussed. The soil was fully characterized before and after each test, and sequential extractions were performed to assess chemico-physical modifications and evaluate metals mobility induced by washing. Results show that both the reducing agents successfully lowered the amount of Cr(VI) in the soil below the threshold allowed by Italian Environmental Regulation for industrial reuse. Cr(VI) reduction by colloidal nZVI proved to be faster and more effective: the civil reuse of soil [Cr(VI)<2mg/kg] was only achieved using colloidal nZVI within 60min adopting a nZVI/Cr(VI) molar ratio of 30. The reducing treatment resulted in an increase in the amount of chromium in the oxide-hydroxide fraction, thus confirming a mechanism of chromium-iron hydroxides precipitation. In addition, a decrease of nickel (Ni) and lead (Pb) content in soil was also observed when acidic conditions were established.

Anaesthesia Management in Patients with Multiple Chemical Sensitivity Syndrome

Multiple Chemical Sensitivity (MCS) is characterised by the appearance of numerous and sometimes severe symptoms, when subjects are in contact with various chemicals and medicinal substances. Currently there are no useful guidelines for managing clinical issues and, specifically, anaesthesia for patients with MCS. This case report describes anaesthesia management in a patient affected by clinically documented MCS and a latex allergy, a candidate for a laparoscopic cholecystectomy operation.

Ghrelin and obestatin in infants, lactating mothers and breast milk

AIM

To investigate the role of ghrelin and obestatin in infancy.

METHODS

We measured ghrelin and obestatin concentrations in blood samples of infants, lactating mothers, and in breast milk.

RESULTS

The median (interquartile range) serum ghrelin concentrations were 922.11 (868.44) pg/ml in infants, 667.88 (942.78) pg/ml in lactating mothers, and 526.4 (439.86) pg/ml in breast milk. The serum obestatin levels were 844.87 (805.14) pg/ml in infants, 759.105 (855.55) pg/ml in lactating mothers, and 846.6 (472.07) pg/ml in breast milk. A positive correlation was found for serum ghrelin concentrations in breastfed infants and lactating mothers (p < 0.001, r = 0.789), serum ghrelin concentrations in breastfed infants and in breast milk (p < 0.001, r = 0.581), serum ghrelin concentrations in lactating mothers and in breast milk (p = 0.021, r = 0.450), and serum obestatin concentrations in breastfed infants and in lactating mothers (p = 0.047, r = 0.609).

CONCLUSION

We report for the first time the serum obestatin concentrations in infants and confirm the presence of correlations between ghrelin and obestatin in lactating mothers and breast milk. The correlations found early in infants' life, when hormones begin to exert their effects on feeding behavior, suggest that they may be involved in these processes.

Adiponectin in breast milk: relation to serum adiponectin concentration in lactating mothers and their infants

AIMS

  The aims of the study were to determine human breast milk adiponectin concentration and to investigate its relationship with serum adiponectin concentration in lactating mothers and their infants and also to evaluate the relationship between serum adiponectin concentration and anthropometric parameters in nurses and infants.

METHODS

  We enrolled 60 healthy term breastfed (BF) infants and their lactating mothers. Adiponectin was determined by radioimmunoassay test in serum and by enzyme-linked immunosorbent assay test in human milk (HM). Infants' and mothers' anthropometric parameters were measured.

RESULTS

  Median (25‰, 75‰) adiponectin concentration in HM was 9.99 (3.59, 20.52) ng/mL. Serum adiponectin concentration in infants was 60.49 (45.76, 74.24) μg/mL and in lactating mothers 21.14 (12.61, 29.66) μg/mL. Adiponectin concentration in HM correlated positively with adiponectin in mothers' serum; r = 0.60 (p < 0.001) and in infants' serum r = 0.37 (p = 0.015). Adiponectin in HM correlated negatively with infants' age r = -0.3 (p = 0.04). Infants' serum adiponectin correlated negatively with their weight r = -0.35 (p = 0.005), length r = -0.35 (p = 0.006) and age r = -0.46 (p < 0.001) and mothers' serum adiponectin with their weight r = -0.37 (p = 0.02) and body mass index r = -0.45 (p = 0.004).

CONCLUSIONS

  The observed correlations between adiponectin in mothers, HM and BF infants may be suggestive for a metabolic link between nurses and infants through milk.