New Sensors for Monitoring pH and Corrosion of Embedded Steel in Mortars during Sulfuric Acid Attack.

The sulfuric acid attack is a common form of degradation of reinforced concrete in contact with industrial wastewater, mine water, acid rain, or in sewage treatment stations. In this work, new pH-sensitive IrOx electrodes were developed for monitoring the pH inside mortar or concrete. To test their ability, the pH sensors were embedded in mortar samples at different depths and the samples were exposed to sulfuric acid solution. In another set of experiments, iron wires were placed at the same depths inside similar mortar samples and their corrosion was monitored as the acid attacked the mortar. Severe acid attack led to cement dissolution and formation of gypsum. The new pH sensors succeeded in measuring the pH changes inside the mortars. The pH gradient, from the high acid environment to the high alkaline mortar interior, occurred in a narrow region. Corrosion of the iron electrodes started only when the acidic solution was in their close vicinity.

New Bis-Cyclometalated Iridium(III) Complexes with ß-Substituted Porphyrin-Arylbipyridine as the Ancillary Ligand: Electrochemical and Photophysical Insights.

An efficient synthetic access to new cationic porphyrin-bipyridine iridium(III) bis-cyclometalated complexes was developed. These porphyrins bearing arylbipyridine moieties at ß-pyrrolic positions coordinated with iridium(III), and the corresponding Zn(II) porphyrin complexes were spectroscopically, electrochemically, and electronically characterized. The features displayed by the new cyclometalated porphyrin-bipyridine iridium(III) complexes, namely photoinduced electron transfer process (PET), and a remarkable efficiency to generate 1O2, allowing us to envisage new challenges and opportunities for their applications in several fields, such as photo(catalysis) and photodynamic therapies.

A corrosion evaluation of mild carbon steel in reclaimed refinery stripped sour water.

Reclaiming water for cooling systems in oil refineries has been strongly encouraged over the past years for decreasing the large consumption of fresh water, thus contributing to the efficient use of this valuable resource. In a recent study [Journal of Environmental Management 261 (2020) 110229], some of the authors studied the retention of phenols in refinery wastewater through reverse osmosis (RO) and found rejections of up to 98% of phenols and 99% of both chemical oxygen demand (COD) and total organic carbon (TOC). The permeates complied with the quality standards for make-up water in cooling processes. A missing aspect, important for the water to be used in the oil and gas industry, was the level of corrosivity of the new permeates. In this work the corrosion of mild carbon steel in the permeates and in the original cooling tower make-up water was studied by electrochemical techniques. The corrosion rate of steel in the permeates in aerated conditions was lower (between 0.053 ± 0.006 and 0.123 ± 0.011 mm year-1) than in the make-up water (0.167 ± 0.030 mm year-1), confirming their suitability for replacing make-up water in the cooling towers. The low corrosion of carbon steel was attributed to the low conductivity and absence of oxidizing species in the fluids, compared to fresh water.

Synthesis and electrochemical study of a hybrid structure based on PDMS-TEOS and titania nanotubes for biomedical applications.

Metallic implants and devices are widely used in the orthopedic and orthodontic clinical areas. However, several problems regarding their adhesion with the living tissues and inflammatory responses due to the release of metallic ions to the medium have been reported. The modification of the metallic surfaces and the use of biocompatible protective coatings are two approaches to solve such issues. In this study, in order to improve the adhesion properties and to increase the corrosion resistance of metallic Ti substrates we have obtained a hybrid structure based on TiO2 nanotubular arrays and PDMS-TEOS films. TiO2 nanotubes have been prepared with two different diameters by means of electrochemical anodization. PDMS-TEOS films have been prepared by the sol-gel method. The morphological and the elemental analysis of the structures have been investigated by scanning electron microscopy and energy dispersive spectroscopy (EDS). Electrochemical impedance spectroscopy (EIS) and polarization curves have been performed during immersion of the samples in Kokubo's simulated body fluid (SBF) at 37 °C to study the effect of structure layers and tube diameter on the protective properties. The obtained results show that the modification of the surface structure of TiO2 and the application of PDMS-TEOS film is a promising strategy for the development of implant materials.

Brushite mineralised Scots pine (Pinus sylvestris L.) sapwood - revealing mineral crystallization within a wood matrix by in situ XRD.

Dicalcium phosphate dihydrate (CaHPO4·2H2O, DCPD, brushite) crystals were synthesised within Scots pine sapwood via a wet-chemistry route from aqueous solutions of Ca(CH3COO)2 and NH4H2PO4 salts. SEM/EDS analysis was used to assess the saturation of the wood cell lumina and cell wall as well as morphological features and elemental composition of the co-precipitated mineral. Brushite mineral crystallization and crystallite growth within the wood matrix was studied by in situ XRD. The chemical composition of the mineral before and after the dissolution was evaluated using FTIR spectroscopy. The overall impact of brushite on the thermal behaviour of wood was studied by TGA/DSC and TGA/DTA/MS analysis under oxidative and pyrolytic conditions. Bending and compression strength perpendicular and parallel to the fibre directions as well as bending strengths in longitudinal and transverse directions of the mineralised wood were also evaluated. Results indicate the viability of the wet-chemistry processing route for wood reinforcement with crystalline calcium phosphate (CaP)-based minerals, and imply a potential in producing hybrid bio-based materials that could be attractive in the construction sector as an environmentally friendly building material.

Predictors of quality of life in patients with refractory mesial temporal lobe epilepsy.

PURPOSE: The identification of variables associated with health-related quality of life (HRQoL) in patients with mesial temporal lobe epilepsy related to hippocampal sclerosis (MTLE-HS) would improve surgical decision-making and post-operatory follow-up in this group of patients. METHODS: We analyzed the independent association between the Quality of Life in Epilepsy Inventory-31 (QOLIE-31) of 81 consecutive patients with refractory MTLE-HS. The clinical, demographic, radiological and electrophysiological variables were analyzed by multiple linear regression analysis. KEY FINDINGS: Approximately 36% (adjusted R(2)=0.36; R coefficient=0.66) of the QOLIE-31 overall score variance was explained by the history of initial precipitant injury, family history of epilepsy, disease duration, age of epilepsy onset, seizure frequency and presence of psychiatric axis-II diagnosis. The variance of QOLIE-31 sub-scales was: seizure worry=7%; overall QOL=11%; emotional well-being=32%; energy/fatigue=38%; cognitive function=13%; medication effects=7%; social function=13% (R coefficient between 0.30 and 0.65). SIGNIFICANCE: The pre-surgical variables studied had relatively low prediction capacity for the overall QOLIE-31 score and its sub-scales in this set of Brazilian patients with refractory MTLE-HS.

Layered double hydroxides for corrosion-related applications-Main developments from 20 years of research at CICECO.

This work describes the main advances carried out in the field of corrosion protection using layered double hydroxides (LDH), both as additive/pigment-based systems in organic coatings and as conversion films/pre-treatments. In the context of the research topic "Celebrating 20 years of CICECO", the main works reported herein are based on SECOP's group (CICECO) main advances over the years. More specifically, this review describes structure and properties of LDH, delving into the corrosion field with description of pioneering works, use of LDH as additives to organic coatings, conversion layers, application in reinforced concrete and corrosion detection, and environmental impact of these materials. Moreover, the use of computational tools for the design of LDH materials and understanding of ion-exchange reactions is also presented. The review ends with a critical analysis of the field and future perspectives on the use of LDH for corrosion protection. From the work carried out LDH seem very tenable, versatile, and advantageous for corrosion protection applications, although several obstacles will have to be overcome before their use become commonplace.

Molybdenum Oxide Thin Films Grown on Flexible ITO-Coated PET Substrates.

Molybdenum oxide thin films were deposited on stiff and flexible substrates by reactive DC magnetron sputtering. Two sets of samples were prepared. The first with different O2/Ar flow rate ratios and the second, fixing the oxygen content, with different time of deposition. As the O2/Ar flow rate ratio varies from 0 up to 0.56, a threshold was found, ranging from crystalline to amorphous nature, and from a nontransparent appearance with metallic-like electrical conductivity to transparent and dielectric behaviour. From the second set, all transparent, the MoOx films present a compact/dense and featureless morphology with thickness from 190 up to 910 nm, depending on the time of deposition. Their structure was corroborated by XPS and Rutherford Backscattering Spectrometry (RBS) and density measurements were performed by RBS and X-ray reflectivity (XRR), revealing a value of 2.4 g/cm3. The surface roughness is in the order of a few nanometers and the maxima optical transmission, in the visible range, is around 89%. Electrochemical cyclic voltammograms showed noticeable color reversibility and reproducibility on the flexible substrates opening new framework possibilities for new electrochomic devices.

Recent Advances on the Application of Layered Double Hydroxides in Concrete-A Review.

The issue of chloride induced corrosion of reinforced concrete is a serious problem affecting infrastructure globally and causing huge economic losses. As such this issue has gained a considerable attention in the scientific community in the recent past. Layered Double Hydroxides (LDHs) have recently emerged as a new class of concrete-additives with a potential to increase the chloride resistance of concrete and mitigate corrosion. LDHs are clay like structures consisting of positively charged layers of cations with associated hydroxides and exchangeable anions in between the layers. Due to this charge balanced structure, LDHs possess the property of encapsulating an anion from the environment and replacing it with an exchangeable anion present in its layers. Potential applications include chloride entrapment in concrete and delivery of corrosion inhibiting anions. However, many versatile compositions of LDHs can be easily synthesized and their application as cement additives reach far beyond corrosion mitigation in concrete. This review presents a summary of recent advances on the applications of LDH in concrete. An extensive set of recently published literature has been critically reviewed and trends have been identified.

Use of ZnAl-Layered Double Hydroxide (LDH) to Extend the Service Life of Reinforced Concrete.

This work investigated the use of ZnAl-layered double hydroxide (LDH) intercalated with nitrate or nitrite ions for controlling the corrosion of steel in reinforced concrete. The work started by analyzing the stability of the powder in the 1-14 pH range and the capacity for capturing chloride ions in aqueous solutions of different pH. The effect of the ZnAl-LDH on the corrosion of steel was studied in aqueous 0.05 M NaCl solution and in mortars immersed in 3.5% NaCl. It was found that the LDH powders dissolved partially at pH > 12. The LDH was able to capture chloride ions from the external solution, but the process was pH-dependent and stopped at high pH due to the partial dissolution of LDH and the preferential exchange of OH- ions. These results seemed to imply that ZnAl-LDH would not work in the alkaline environment inside the concrete. Nonetheless, preliminary results with mortars containing ZnAl-LDH showed lower penetration of chloride ions and higher corrosion resistance of the steel rebars.

Light-Induced Proton Pumping with a Semiconductor: Vision for Photoproton Lateral Separation and Robust Manipulation.

Energy-transfer reactions are the key for living open systems, biological chemical networking, and the development of life-inspired nanoscale machineries. It is a challenge to find simple reliable synthetic chemical networks providing a localization of the time-dependent flux of matter. In this paper, we look to photocatalytic reaction on TiO2 from different angles, focusing on proton generation and introducing a reliable, minimal-reagent-consuming, stable inorganic light-promoted proton pump. Localized illumination was applied to a TiO2 surface in solution for reversible spatially controlled "inorganic photoproton" isometric cycling, the lateral separation of water-splitting reactions. The proton flux is pumped during the irradiation of the surface of TiO2 and dynamically maintained at the irradiated surface area in the absence of any membrane or predetermined material structure. Moreover, we spatially predetermine a transient acidic pH value on the TiO2 surface in the irradiated area with the feedback-driven generation of a base as deactivator. Importantly we describe how to effectively monitor the spatial localization of the process by the in situ scanning ion-selective electrode technique (SIET) measurements for pH and the scanning vibrating electrode technique (SVET) for local photoelectrochemical studies without additional pH-sensitive dye markers. This work shows the great potential for time- and space-resolved water-splitting reactions for following the investigation of pH-stimulated processes in open systems with their flexible localization on a surface.

Control of crystallite and particle size in the synthesis of layered double hydroxides: Macromolecular insights and a complementary modeling tool.

Zinc-aluminum layered double hydroxides with nitrate intercalated (Zn(n)Al-NO3, n=Zn/Al) is an intermediate material for the intercalation of different functional molecules used in a wide range of industrial applications. The synthesis of Zn(2)Al-NO3 was investigated considering the time and temperature of hydrothermal treatment. By examining the crystallite size in two different directions, hydrodynamic particle size, morphology, crystal structure and chemical species in solution, it was possible to understand the crystallization and dissolution processes involved in the mechanisms of crystallite and particle growth. In addition, hydrogeochemical modeling rendered insights on the speciation of different metal cations in solution. Therefore, this tool can be a promising solution to model and optimize the synthesis of layered double hydroxide-based materials for industrial applications.

Diffusion tensor imaging abnormalities in focal cortical dysplasia.

PURPOSE: Focal cortical dysplasia (FCD) is one of the most common underlying pathologic substrates in patients with medically intractable epilepsy. While magnetic resonance imaging (MRI) evidence of FCD is an important predictor of good surgical outcome, conventional MRI is not sensitive enough to detect all lesions. Previous reports of diffusion tensor imaging (DTI) abnormalities in FCD suggest the potential of DTI in the detection of FCD. The purpose of this study was to study subcortical white matter underlying small lesions of FCD using DTI. METHODS: Five patients with medically intractable epilepsy and FCD were investigated. Diffusion tensor imaging images were acquired (20 contiguous 3 mm thick axial slices) with maps of fractional anisotropy (FA), trace apparent diffusion coefficient (trace/3 ADC), and principal eigenvalues (ADC parallel and ADC perpendicular to white matter tracts) being calculated for each slice. Region of interest analysis was used to compare subcortical white matter ipsilateral and contralateral to the lesion. RESULTS: Three subjects with FCD associated with underlying white matter hyperintensities on T2 weighted MRI were observed to have increased trace/3 ADC, reduced fractional anisotropy and increased perpendicular water diffusivity which was greater than the relative increase in the parallel diffusivity. No DTI abnormalities were identified in two patients with FCD without white matter hyperintensities on conventional T2-weighted MRI. CONCLUSIONS: While DTI abnormalities in FCD with obvious white matter involvement are consistent with micro-structural degradation of the underlying subcortical white matter, DTI changes were not identified in FCD lesions with normal appearing white matter.

Smart electroconductive bioactive ceramics to promote in situ electrostimulation of bone.

Biomaterials can still be reinvented to become simple and universal bone regeneration solutions. Following this roadmap, conductive CNT-based "smart" materials accumulate exciting grafting qualities for tuning the in vitro cellular phenotype. Biphasic electrical stimulation of human osteoblastic cells was performed in vitro on either dielectric bioactive bone grafts or conductive CNT-reinforced composites. The efficiency of the electrical stimuli delivery, as well as the effect of stimulation on cellular functions were investigated. Conductive substrates boosted the local culture medium conductivity and the confinement of the exogenous electrical fields. Hence, bone cell proliferation, DNA content and mRNA expression were maximized on the conductive substrates yielding superior stimuli delivering efficiency over dielectric ones. These findings are suggestive that bioactive bone grafts with electrical conductivity are capable of high spatial and temporal control of bone cell stimulation.

Severe Amnesia in Epilepsy: Causes, Anatomopsychological Considerations, and Treatment.

Severe amnesia in epileptic patients is a catastrophic condition that may be due to different etiologies. Because of the striking findings and thorough neuropsychological studies of Patient H.M., the literature has focused on postsurgical occurrence of such memory impairment, with much less emphasis on other causes. Here we summarize, for comparison, the history of H.M. We report five patients with pronounced memory loss who had extensive neuropsychological and electroencephalographic testing. MRI was also performed in four of the patients, MRI volumetric measurements of amygdala and hippocampal formation in three, and measurements of entorhinal cortex in two. The amnesia occurred after head trauma in one patient, following encephalitis in one, after partial status epilepticus in two, and after unilateral surgical resection in a woman with bilateral lesions. On the basis of these studies it was impossible to distinguish the role of recurrent temporal lobe epileptic seizures as distinct from underlying lesions in the genesis and course of the memory loss. We review here the anatomical substrate, neuropsychological, and other investigations and the etiological factors leading to the amnesia in these patients, together with current concepts regarding possible causes of such severe memory dysfunction. In patients with this degree of severity of memory deficit, temporal resection in an attempt to control seizures did not lead to a measurable increase in memory problems. It also, however, did not bring about worthwhile improvement in seizure control.

Anônimos supercampeões: a equipe de rafting Bozo D´água e a caracterização dos esportes de aventura / Anonim superchampions: Bozo D'água rafting team and the characterization of adventure sports / Anónimos supercampeones: el equipo de rafting Bozo D'agua y la caracterización de los deportes de aventura

O objetivo deste artigo foi problematizar a caracterização dos esportes de aventura a partir do caso da equipe de rafting Bozo D'água, um contraexemplo em relação à literatura pioneira sobre o tema. Parte de etnografia mais ampla, o presente texto analisa dez entrevistas cotejadas com observação de campo. Os resultados indicam que, ao contrário da prática de aventura caracterizada como participação não competitiva de lazer, o esporte de alto rendimento foi a alternativa para viabilizar a participação esportiva em atividade de aventura para praticantes de classes sociais baixas. Conclui-se que diferentes formas de apropriação e distintas versões do esporte de aventura variam conforme contexto e questões de classe e que o potencial das práticas de aventura, de colocar em circulação valores esportivos alternativos, perde espaço na medida em que as políticas públicas brasileiras priorizam o esporte de alto rendimento.

This paper´s objective was to analyse the characterization of adventure sports though the analysis of the practice conditions of the Brazilian rafting team called Bozo D´água, a counterexample regarding the literature review. Part of an ethnography, it is focused on ten in depth interviews and field observation. The results indicate that, on the contrary of the adventure practice described as leisure participation, high performance sport was the only possibility of adventure participation for those athletes. Concluding that different versions of adventure sports vary according to class issues, and the potential for circulating alternative sportive values of the adventure practices lose space as Brazilian public politics prioritize high performance sports.

El objetivo de este artículo fue problematizar la caracterización de los deportes de aventura a partir del caso del equipo de rafting Bozo de agua, un contraejemplo en relación a la revisión de literatura. Parte de una etnografía más amplia, se centra en diez entrevistas en profundidad cotejándolas con la observación de campo. Los resultados indican que, diferentemente de la práctica de aventura caracterizada como participación no competitiva de ocio, el deporte de alto rendimiento fue la alternativa para viabilizar la participación en actividad de aventura para practicantes de clases bajas. Se concluye que diferentes formas de apropiación y distintas versiones de los deportes de aventura varían según contexto y cuestiones de clase y que el potencial de las prácticas de aventura de poner en circulación valores deportivos alternativos pierde espacio en la medida en que las políticas públicas brasileñas priorizan el deporte De alto rendimiento.

Hippocampal sclerosis and ipsilateral headache among mesial temporal lobe epilepsy patients.

PURPOSE: To investigate the frequency and patterns of headache in a well-defined and homogeneous group of mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS) patients. METHODS: One hundred consecutive MTLE-HS patients under comprehensive presurgical evaluation were evaluated from May 2009 to April 2010. A standardized questionnaire was applied according to the criteria of the International Headache Society (IHS). Headache diagnosis was based on the second edition of the International Classification of Headache Disorders (ICHD-II). RESULTS: Ninety-two patients (92%) had at least one headache episode during the previous 12 months. Migraine occurred in 51.9% of patients and tension-type headache (TTH) in 39.1%. Patients with migraine presented higher frequency (p=0.002) and severity of episodes (p<0.001), as well as lateralized pain (p=0.001) than individuals with TTH. MTLE-HS patients with unilateral HS and predominantly unilateral headache (irrespective of the type), presented pain ipsilateral to the HS (OR 8.5; CI 95%=2.1-35.1; p=0.003). CONCLUSIONS: Headache is a frequent clinical symptom of lateralizing value, which may share common pathophysiology with epileptogenesis among MTLE-HS patients.

Cognitive functioning in bilateral perisylvian polymicrogyria (BPP): clinical and radiological correlations.

Bilateral perisylvian polymicrogyria (BPP) is a malformation of cortical development, frequently associated with severe dysarthria or anarthria. BPP patients are therefore often labeled as severely retarded, but a detailed neuropsychological profile has not been reported to date. In a series of 14 patients, we demonstrated that only a minority had extremely low intelligence, and that some aspects of cognitive function correlated with the extent of the cortical disorganization. Early age at seizure onset correlated positively with Performance IQ scores (P<0.05) and negatively with the extent of the lesion (P<0.01), reflecting that patients with more severe BPP are more likely to have early seizure onset, resulting in greater interference with ongoing cognitive development. Receptive and expressive language skills were found to be equally poor. Frontal lobe function and memory abilities were relatively well preserved, suggesting that the observed cognitive profiles were related, at least in part, to specific areas of cortical dysfunction and not only to global dysfunction.

Subcortical band heterotopia (SBH) in males: clinical, imaging and genetic findings in comparison with females.

Subcortical band heterotopia (SBH) or double cortex syndrome is a neuronal migration disorder, which occurs very rarely in males: to date, at least 110 females but only 11 in males have been reported. The syndrome is usually associated with mutations in the doublecortin (DCX) (Xq22.3-q23) gene, and much less frequently in the LIS1 (17p13.3) gene. To determine whether the phenotypic spectrum, the genetic basis and genotype-phenotype correlations of SBH in males are similar to those in females, we compared the clinical, imaging and molecular features in 30 personally evaluated males and 60 previously reported females with SBH. Based on the MRI findings, we defined the following band subtypes: partial, involving one or two cerebral lobes; intermediate, involving two lobes and a portion of a third; diffuse, with substantial involvement of three or more lobes; and pachygyria-SBH, in which posterior SBH merges with anterior pachygyria. Karyo typing and mutation analysis of DCX and/or LIS1 were performed in 23 and 24 patients, respectively. The range of clinical phenotypes in males with SBH greatly overlapped that in females. MRI studies revealed that some anatomical subtypes of SBH, such as partial and intermediate posterior, pachygyria-SBH and diffuse bands with posterior predominance, were more frequently or exclusively present in males. Conversely, classical diffuse SBH and diffuse bands with anterior predominance were more frequent in females. Males had either mild or the most severe band subtypes, and these correlated with the over-representation of normal/borderline intelligence and severe mental retardation, respectively. Conversely, females who had predominantly diffuse bands exhibited mostly mild or moderate mental retardation. Seven patients (29%) had missense mutations in DCX; in four, these were germline mutations, whereas in three there was evidence for somatic mosaicism. A germline missense mutation of LIS1 and a partial trisomy of chromosome 9p were identified in one patient (4%) each. One male each had a possible pathogenic intronic base change in both DCX and LIS1 genes. Our study shows that SBH in males is a clinically heterogeneous syndrome, mostly occurring sporadically. The clinical spectrum is similar to that of females with SBH. However, the greater cognitive and neuroradiological heterogeneity and the small number of mutations identified to date in the coding sequences of the DCX and LIS1 genes in males differ from the findings in females. This suggests other genetic mechanisms such as mutations in the non-coding regions of the DCX or LIS1 genes, gonadal or somatic mosaicism, and finally mutations of other genes.