bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of non-ionic surfactant on the internal corrosion for X52 steel in extra-heavy crude oil-in-water emulsions
Authors: Quej-Ake L.M. , Contreras A. , Aburto Jorge 
Published: May 2018

PurposeThe purpose of this research is to study different extra-heavy crude oil-in-water emulsions that can be found in practice for corrosion process of X52 steel adding 60 mg.L-1 of non-ionic surfactant and a corrosion inhibitor (CI). Electrochemical impedance spectroscopy and Tafel plots are carried out. Thus, Bode-modulus and Bode-phase angle plots are discussed. Adsorption isotherms obtained from corrosion rate (CR) values are taken into account.Design/methodology/approachTwo-electrode arrangement is used to characterize the pseudo-capacitance values for X52 steel exposed to water and crude oil phases, mainly. Electrochemical evaluations for X52 steel exposed to extra-heavy crude oil-in-water emulsions are recorded in a conventional three-electrode cell to study the corrosion process as was documented in detail by Quej-Ake et al. (2015). Therefore, all electrodes are placed as close as possible to eliminate the iR-drop.FindingsPseudo-capacitance analysis shows that X52 steel immersed in oilfield produced water was more susceptible to corrosion than that immersed in ocean water solution and extra-heavy crude oil phase. After being analyzed, the X52 steel surface coverage and adsorption process for surfactant and CI could be concluded that surfactant could protect the metal surface. In a coalescence extra-heavy crude oil-in-water emulsion, the water medium generated a new solution that was more corrosive than the original water phase. Wash crude oil process was provoked in emulsion systems to sweep up the salts, mainly. Thus, corrosive species that can be recovered inside extra-heavy crude oil may appear, and in turn a new more corrosive solution could be obtained. Taking into account the straight line obtained in Bode-modulus plot for X52 exposed to extra-heavy crude oil, it is possible to point out that the negative value of the slope orR2can be related to a coefficient (Jorcin et al., 2006). It is important to mention that electrochemical responses for X52 steel exposed to extra-heavy crude oil-in-water under coalescence emulsions revealed that corrosion and diffusion processes exist. Therefore, a possible good inhibitor is surfactant in emulsion systems.Originality/valueCR and anodic and cathodic slopes suggest that the surfactant acted as mixed CI. Of these, susceptible anodic (MnS and perlite or cementite) and cathodic (ferrite) sites on steel surface could be affected, due to which physicochemical adsorption could happen by using electrochemical parameters analysis. Thus, no stable emulsions should be taken into account for extra-heavy crude oil transportation, because corrosion problems in atmospheric distillation process of the crude oil due to stable emulsion cannot be easily separated. In this manner, coalescent emulsions are more adequate for transporting extra-heavy crude oil because low energy to separate the water media is required.
A taxonomy of performance shaping factors for shield tunnel construction
Authors: Li Jue , Yu Minghui , Wang Hongwei 
Published: May 2018

PurposeOn shield tunnel construction (STC) site, human error is widely recognized as essential to accident. It is necessary to explain which factors lead to human error and how these factors can influence human performance. Human reliability analysis supports such necessity through modeling the performance shaping factors (PSFs). The purpose of this paper is to establish and validate a PSF taxonomy for the STC context.Design/methodology/approachThe approach taken in this study mainly consists of three steps. First, a description of the STC context is proposed through the analysis of the STC context. Second, the literature which stretch across the PSF methodologies, cognitive psychology and human factors of STC and other construction industries are reviewed to develop an initial set of PSFs. Finally, a final PSF set is modified and validated based on STC task analysis and STC accidents cases.FindingsThe PSF taxonomy constituted by 4 main components, 4 hierarchies and 85 PSFs is established for human behavior modeling and simulation under the STC context. Furthermore, by comparing and evaluating the performance of STC PSF and existing PSF studies, the proposed PSF taxonomy meets the requirement for qualitative and quantitative analysis.Practical implicationsThe PSF taxonomy can provide a basis and support for human behavior modeling and simulation under the STC context. Integrating PSFs into a behavior simulation model provides a more realistic and integrated assessment of human error by manifesting the influence of each PSFs on the cognitive processes. The simulation results can suggest concrete points for the improvement of STC safety management.Originality/valueThis paper develops a taxonomy of PSFs that addresses the various unique influences of the STC context on human behaviors. The harsh underground working conditions and diverse resources of system information are identified as key characteristics of the STC context. Furthermore, the PSF taxonomy can be integrated into a human cognitive behavior model to predict the worker’s behavior on STC site in future work.
Banking stability determinants in Africa
Authors: Ozili Peterson K. 
Published: May 2018

Purpose
The purpose of this paper is to investigate the determinants of banking stability in Africa.

Design/methodology/approach
The authors present four measures of banking stability embedding banks’ loan loss coverage ratio, insolvency risk, asset quality ratio, and level of financial development, thereby allowing analysis of banking stability determinants from four complementary perspectives: protection for downside credit losses, distress arising from insolvency risk, non-performing loans, and financial development. The authors use the regression methodology to estimate the impact of financial structure, institutional, bank-level factors on bank stability.

Findings
The findings indicate that banking efficiency, foreign bank presence, banking concentration, size of banking sector, government effectiveness, political stability, regulatory quality, investor protection, corruption control and unemployment levels are significant determinant of banking stability in Africa and the significance of each determinant depends on the banking stability proxy employed and depends on the period of analysis: pre-crisis, during-crisis or post-crisis.

Practical implications
Banking supervisors in African countries should consider the role of financial structure and institutional quality for banking stability in the African region.

Originality/value
This study is the first to examine banking stability determinants in Africa that takes into account institutional quality and financial structure.
Psychological capital as a personal resource in the JD-R model
Authors: Grover Steven L. , Teo Stephen T.T. , Pick David , Roche Maree , Newton Cameron J. 
Published: May 2018

Purpose
The purpose of this paper is to demystify the role of the personal resource of psychological capital (PsyCap) in the job demands-resources model. The theory suggests that personal resources directly influence perceptions of job demands, job resources, and outcomes. Alternatively, personal resources may moderate the impact of job demands and job resources on outcomes.

Design/methodology/approach
A survey of 401 nurses working in the Australian healthcare sector explores the relations among PsyCap, job demands and resources, and psychological well-being and work engagement.

Findings
The results suggest that PsyCap directly influences perceptions of job demands and resources and that it directly influences the outcomes of well-being and engagement. Furthermore, job demands and job resources mediate the relation of PsyCap with well-being and engagement, respectively.

Research limitations/implications
The moderation effect of PsyCap was not supported, which suggests that PsyCap relates to perceptions as opposed to being a coping mechanism. This finding therefore narrows the scope of personal resources in this important model.

Originality/value
The importance of this study lies in its exploration of various ways that personal resources can influence this dominant model and in analyzing the global construct of PsyCap as opposed to some of its constituent parts.
Nonlinear effects of phenological shifts link interannual variation to species interactions
Authors: Rudolf Volker H. W. 
Published: May 2018

Abstract

The vast majority of species interactions are seasonally structured and depend on species' relative phenologies. However, differences in the phenologies of species naturally vary across years and are altered by ongoing climate change around the world.

By combining experiments that shifted the relative hatching of two competing tadpole species across a productivity gradient with simulations of inter‐annual variation in arrival times I tested how phenological variation across years can alter the strength and outcome of interspecific competition.

Shifting the relative timing of hatching (phenology) of a species fundamentally altered interspecific competition, and the effect of shifting the timing on competition was highly non‐linear for most demographic rates. Furthemore, this relationship varied with productivity of the system. As a consequence, (a) shifts in relative timing of phenologies had small or large effects depending on the average natural timing of interactions, and (b) changes in the inter‐annual variation in onset of interaction alone can alter species interactions in simulations even when mean phenologies (timing) remain unchanged across years.

Studies on phenologies traditionally focus on directional shifts in the mean of phenologies, but these results suggest that we also need to consider inter‐annual variation in phenologies of interacting species to predict dynamics of natural communities and how they will be modified by climate change.
Synthesis, characterization and electrochemistry studies of iron(III) complex with curcumin ligand
Authors: Özbolat Gülüzar , Yegani Arash Alizadeh , Tuli Abdullah 
Published: May 2018

SummaryIron overload is a serious clinical condition for humans and is a key target in drug development. The aim of this study was to investigate the coordination of iron(III) ions with curcumin ligand that may be used in the treatment of iron overload. Iron(III) complex of curcumin was synthesized and structurally characterized in its solid and solution state by FT‐IR, UV‐Vis, elemental analysis, and magnetic susceptibility. Electrochemical behaviour of the ligand and the complexes were examined using cyclic voltammetry. The cytotoxic activities of the ligand and the iron(III) complex were evaluated by the MTT assay. Curcumin reacted with iron in high concentrations at physiological pH at room temperature. Subsequently, a brown‐red complex was formed. Data regarding magnetic susceptibility showed that the complexes with a 1:2 (metal/ligand) mole ratio had octahedral geometry. The complex showed higher anti‐oxidant effect towards the cell line ECV304 at IC50 values of 4.83 compared to curcumin. The complex exhibited very high cytotoxic activity and showed a cytotoxic effect that was much better than that of the ligand. The potentials for redox were calculated as 0.180 V and 0.350 V, respectively. The electrochemistry studies showed that Fe3+/Fe2+ couple redox process occurred at low potentials. This value was within the range of compounds that are expected to show superoxide dismutase activity. This finding indicates that the iron complex is capable of removing free radicals. The observed cytotoxicity could be pursued to obtain a potential drug. Further studies investigating the use of curcumin for this purpose are needed.
Are Archetypes Essential?
Authors: Colman Warren 
Published: May 2018

AbstractThis paper distinguishes between Jung's theoretical discourse regarding the archetypes and his phenomenological account of numinous experience. For this author, the initial attraction of ‘my Jung’ came from both the vivid Romanticism of his descriptions of the anima and the apparent ‘ground of being’ offered by his theory of archetypes. However, the essentialism inherent to archetypal theory in general and the anima in particular has necessitated a re‐evaluation of Jung's theory in terms of emergence theory. My own version of this emphasises the role of symbols in the constitution of affect through collective human action in the world. In this reconfiguration, the visceral energy of numinous experience is retained while the problematic theory of archetypes is no longer needed.
Are Shocks Transitory or Permanent? An Inquiry into Agricultural Commodity Prices
Authors: Ghoshray Atanu 
Published: May 2018

AbstractThis paper contributes to the contentious topic of whether shocks to agricultural commodity prices are permanent or transitory. This is an important issue with regards to forecasting, economic modelling of agricultural prices and risk management. Past studies have not accounted for important characteristics of agricultural prices that matter when testing whether shocks to prices are permanent or transitory. These include the presence or absence of a deterministic trend, the possible break in the trend, non‐stationary volatility, and the problem of the initial deviation of commodity prices from their long‐run mean or trend. We conduct a comprehensive test that incorporates all these characteristics known to plague agricultural commodity prices. Though the conclusion is mixed, the balance is in favour of agricultural price shocks being permanent in nature. This result departs from the general view that in theory, agricultural prices should be stationary, suggesting that the controversy of whether shocks to agricultural prices are temporary or permanent is not yet over.
Usual energy and macronutrient intakes in a large sample of Iranian middle‐aged and elderly populations
Authors: Heidari Zahra , Feizi Awat , Azadbakht Leila , Mohammadifard Noushin , Maghroun Maryam , Sarrafzadegan Nizal 
Published: May 2018

AimThe present study aimed to assess the usual distribution of energy and macronutrient intake among a large representative sample of Iranian healthy middle‐aged and elderly people.MethodsIn this cross‐sectional study, a second follow‐up survey of the Isfahan Cohort Study (ICS) was carried out; 1922 people aged 40 years and older were investigated. Dietary intakes were collected using 24‐hour recall and two or more consecutive food records. Distribution of energy and macronutrient intake was estimated using traditional and National Cancer Institute (NCI) methods.ResultsThe mean usual intake of energy was 1749.2 kcal based on the NCI method. Carbohydrate constituted 59.98% and protein 17.42% of total energy intake. The mean contributions of total fat, saturated fatty acids (SFA), polyunsaturated fatty acids (PUFA) and monounsaturated fatty acids (MUFAs) to energy intake were 25.74%, 9.5%, 4.92 and 7.75%, respectively. Approximately 7% of studied females aged 51–70 years met the recommended or higher levels for fibre. Females had significantly higher compliance of the recommended cholesterol level than males (age range of 40–70 years; P < 0.0001).ConclusionsIt appears that Iranian middle‐aged and elderly people are advancing towards a high risk of obesity and non‐communicable chronic diseases. Nutritional interventions for improving the diet amongst this at‐risk population are necessary.
Differential mRNA expression of neuroinflammatory modulators in the spinal cord and thalamus of type 2 diabetic monkeys
Authors: Ding Huiping , Kiguchi Norikazu , Kishioka Shiroh , Ma Tao , Peters Christopher M. , Ko Mei‐Chuan 
Published: May 2018

AbstractBackgroundGiven that diabetes‐associated complications are closely associated with neuroinflammation, it is imperative to study potential changes in neuroinflammatory modulators in the central nervous system of diabetic primates.MethodsThe mRNA levels of pro‐ and anti‐inflammatory cytokines, toll‐like receptors (TLRs), growth factors, and cannabinoid receptors were compared in the spinal dorsal horn (SDH) and thalamus of naturally occurring type 2 diabetic monkeys and an age‐matched control group using reverse transcription and quantitative real‐time polymerase chain reaction.ResultsIn the SDH of diabetic monkeys, mRNA levels of proinflammatory cytokines (i.e. interleukin [IL]‐1β and tumor necrosis factor [TNF] α), TLR1, and TLR2 were increased, whereas mRNA levels of IL‐10, an anti‐inflammatory cytokine, were decreased. No changes were observed in the mRNA levels of growth factors and cannabinoid receptors. In line with the mRNA data, TNFα immunoreactivity was significantly increased in diabetic monkeys. Moreover, mRNA expression levels of IL‐1β, TNFα, TLR1, and TLR2 in the SDH were positively correlated with plasma glucose concentrations in all monkeys.ConclusionsSeveral ligands and receptors involved in neuroinflammation are simultaneously dysregulated in the spinal cord of diabetic monkeys. This primate disease model will facilitate the design of novel treatment approaches to ameliorate neuroinflammation‐driven adverse effects in diabetic patients.
Trimethylamine‐N‐oxide promotes brain aging and cognitive impairment in mice
Authors: Li Dang , Ke Yilang , Zhan Rui , Liu Changjie , Zhao Mingming , Zeng Aiping , Shi Xiaoyun , Ji Liang , Cheng Si , Pan Bing , Zheng Lemin , Hong Huashan 
Published: May 2018

SummaryGut microbiota can influence the aging process and may modulate aging‐related changes in cognitive function. Trimethylamine‐N‐oxide (TMAO), a metabolite of intestinal flora, has been shown to be closely associated with cardiovascular disease and other diseases. However, the relationship between TMAO and aging, especially brain aging, has not been fully elucidated. To explore the relationship between TMAO and brain aging, we analysed the plasma levels of TMAO in both humans and mice and administered exogenous TMAO to 24‐week‐old senescence‐accelerated prone mouse strain 8 (SAMP8) and age‐matched senescence‐accelerated mouse resistant 1 (SAMR1) mice for 16 weeks. We found that the plasma levels of TMAO increased in both the elderly and the aged mice. Compared with SAMR1‐control mice, SAMP8‐control mice exhibited a brain aging phenotype characterized by more senescent cells in the hippocampal CA3 region and cognitive dysfunction. Surprisingly, TMAO treatment increased the number of senescent cells, which were primarily neurons, and enhanced the mitochondrial impairments and superoxide production. Moreover, we observed that TMAO treatment increased synaptic damage and reduced the expression levels of synaptic plasticity‐related proteins by inhibiting the mTOR signalling pathway, which induces and aggravates aging‐related cognitive dysfunction in SAMR1 and SAMP8 mice, respectively. Our findings suggested that TMAO could induce brain aging and age‐related cognitive dysfunction in SAMR1 mice and aggravate the cerebral aging process of SAMP8 mice, which might provide new insight into the effects of intestinal microbiota on the brain aging process and help to delay senescence by regulating intestinal flora metabolites.
Feasibility and Acceptability of Maternal Choline Supplementation in Heavy Drinking Pregnant Women: A Randomized, Double‐Blind, Placebo‐Controlled Clinical Trial
Authors: Jacobson Sandra W. , Carter R. Colin , Molteno Christopher D. , Meintjes Ernesta M. , Senekal Marjanne S. , Lindinger Nadine M. , Dodge Neil C. , Zeisel Steven H. , Duggan Christopher P. , Jacobson Joseph L. 
Published: May 2018

BackgroundCholine, an essential nutrient, serves as a methyl‐group donor for DNA methylation and is a constituent of the neurotransmitter acetylcholine and a precursor to major components of cell membranes. Findings from animal studies suggest that choline supplementation during pregnancy can mitigate adverse effects of prenatal alcohol exposure on growth and neurocognitive function. We conducted a randomized, double‐blind exploratory trial to examine feasibility and acceptability of a choline supplementation intervention during pregnancy.MethodsSeventy heavy drinkers, recruited in mid‐pregnancy, were randomly assigned to receive a daily oral dose of 2 g of choline or a placebo from time of enrollment until delivery. Each dose consisted of an individually wrapped packet of powder that, when mixed with water, produced a sweet tasting grape‐flavored drink. Adherence was assessed by collecting used and unused drink packets on a monthly basis and tabulating the number used. Side effects were assessed in monthly interviews. Blood samples obtained at enrollment and at 4 and 12 weeks after randomization were assayed for plasma choline concentration.ResultsAdherence was good‐to‐excellent (median doses taken = 74.0%; interquartile range = 53.9 to 88.7%) and was not related to a range of sociodemographic characteristics or to alcohol consumption ascertained using a timeline follow‐back interview. By 4 weeks, plasma choline concentrations were significantly higher in the choline supplementation than the placebo arm, and this group difference continued to be evident at 12 weeks. The only side effect was a small increase in nausea/dyspepsia. No effects were seen for diarrhea, vomiting, muscle stiffness, blood pressure, or body odor changes.ConclusionsThis study demonstrated that a choline supplementation program with very heavy drinkers during pregnancy is feasible even among highly disadvantaged, poorly educated women. The broad acceptability of this intervention is indicated by our finding that adherence was not related to maternal education, intellectual function, depression, nutritional status, or alcohol use.
Efficacy of Maternal Choline Supplementation During Pregnancy in Mitigating Adverse Effects of Prenatal Alcohol Exposure on Growth and Cognitive Function: A Randomized, Double‐Blind, Placebo‐Controlled Clinical Trial
Authors: Jacobson Sandra W. , Carter R. Colin , Molteno Christopher D. , Stanton Mark E. , Herbert Jane S. , Lindinger Nadine M. , Lewis Catherine E. , Dodge Neil C. , Hoyme H. Eugene , Zeisel Steven H. , Meintjes Ernesta M. , Duggan Christopher P. , Jacobson Joseph L. 
Published: May 2018

BackgroundWe recently demonstrated the acceptability and feasibility of a randomized, double‐blind choline supplementation intervention for heavy drinking women during pregnancy. In this study, we report our results relating to the efficacy of this intervention in mitigating adverse effects of prenatal alcohol exposure (PAE) on infant growth and cognitive function.MethodsSixty‐nine Cape Coloured (mixed ancestry) heavy drinkers in Cape Town, South Africa, recruited in mid‐pregnancy, were randomly assigned to receive a daily oral dose of either 2 g of choline or placebo from time of enrollment until delivery. Each dose consisted of an individually wrapped packet of powder that, when mixed with water, produced a sweet tasting grape‐flavored drink. The primary outcome, eyeblink conditioning (EBC), was assessed at 6.5 months. Somatic growth was measured at birth, 6.5, and 12 months, recognition memory and processing speed on the Fagan Test of Infant Intelligence, at 6.5 and 12 months.ResultsInfants born to choline‐treated mothers were more likely to meet criterion for conditioning on EBC than the placebo group. Moreover, within the choline arm, degree of maternal adherence to the supplementation protocol strongly predicted EBC performance. Both groups were small at birth, but choline‐treated infants showed considerable catch‐up growth in weight and head circumference at 6.5 and 12 months. At 12 months, the infants in the choline treatment arm had higher novelty preference scores, indicating better visual recognition memory.ConclusionsThis exploratory study is the first to provide evidence that a high dose of choline administered early in pregnancy can mitigate adverse effects of heavy PAE on EBC, postnatal growth, and cognition in human infants. These findings are consistent with studies of alcohol‐exposed animals that have demonstrated beneficial effects of choline supplementation on classical conditioning, learning, and memory.