Global brands:The Evolution of Multinationals in Alcoholic Beverages. By Teresa da Silva Lopes. New York: Cambridge University Press, 2007. xxii + 303 pp. Illustrations, tables, appendix, bibliography, notes, index. Cloth, $50.00. ISBN: 978-0-521-83397-4.

Book review

Placebo expectancy effect of consuming psychoactive beverages on cognition and mood

Energy drinks have become very popular over the past few years with over half the student population in colleges and universities consuming them at least once a month (Malinauskas et al., 2007). It has been reported that the most common reasons why students consume energy drinks are to maintain alertness, reduce symptoms of hangover, increase energy, to help with driving and to prevent sleepiness (Attila and Cakir, 2011; Malinauskas et al., 2007). Previous research has suggested that energy drinks enhance sensorimotor speed, behaviour, and reduce levels of fatigue (Alford et al., 2001; Horne and Reyner, 2001; Howard and Marczinski, 2010; Kennedy and Scholey, 2004; Smit et al., 2004). The two key ingredients found in energy drinks are caffeine and glucose which have been examined together and alone, which have indicated enhanced reaction times, improvement in both verbal memory and sustained attention and more recently there is evidence to show that expectancy may play a key role in predicting intentions of future consumption (Adan and serra-Grabulosa, 2010). According to Kirsch (1997) people have specific expectations when they consume psychoactive substances that trigger physiological and psychological reactions, which tend to be independent of the psychoactive substance ingested. The concept of expectancy effects can be unambiguous especially when the information provided to the participants prior to the experimental study is specific to a possible outcome response. This thesis investigated the extent of expectancy effect on cognition and mood when psychoactive drinks containing caffeine and glucose were consumed in comparison to non-psychoactive drinks. The investigation commenced with examining the independent effects of caffeine and glucose, followed by the combination of caffeine and glucose as an energy drink on mood and cognition. The investigation advanced by comparing drink presentation effects (i.e., consuming the experimental drink from a branded bottle versus from a glass) irrespective of drink content on mood and cognition. Finally, the investigation lead to exploring what factors may predict expectancy effects when participants’ consumed psychoactive drinks among healthy adults. This was done by applying the Theory of Planned Behaviour model (TPB) (Azjen, 1991) to explore the contribution of specific attitudes, subjective norms and perceived behavioural control to the extent of expectancy effects as well as to behavioural intention, with additional variables including; beliefs, habits, past-behaviour, selfidentity. Self-identity representing someone who drinks energy drinks regularly. The level of internal consistency for Cronbach’s alpha was conducted for each variable within the TPB model and for the additional variables included for test reliability. This thesis consisted of four studies, which found that consumption of caffeine and glucose independently and also in combination resulted in psychoactive effects on mood and cognition. Experiment 2 was the only study, which indicated an expectancy effect for immediate verbal recall task and the mood subscale tension. Conversely, for experiment 4 there was a reverse effect found for the immediate verbal recall task. However, there were significant expectancy and psychoactive effects found for mood subscales throughout the four studies. It was also found that the TPB model had two significant variables past-behaviour and self-identity predicted intentions suggesting that participants who regularly consume psychoactive beverages have salient beliefs about consuming psychoactive drinks and the TPB model can be utilised to predict their intentions. Furthermore, the Theory of planned behaviour model found that habit and self-identity significantly predicted participants’ expectancy effects on the vigour. Indicating consumers of energy drinks are familiar with expected outcome response. This model was unsuccessful in predicting expectancy response for cognitive performance. Thus, overall the findings from the four studies indicated that caffeine and glucose have cognitive enhancing properties, which also positively improve mood. However, expectancy effects have been identified for mood only, whereas the overall findings within this thesis were unable to identify significant predictors of expectancy effect and response.

Microstructural analysis of surface and interface zones in concrete

Several of OPC paste and concrete specimens, with different mix proportions, were cast against CPF and impermeable formwork (IF) and the profiles of pore structure, microhardness and scratch hardness of the cover zone were established. The chloride ingress and the depth of carbonation of the surface zone of concrete cast against CPF and IF were investigated. The main mechanisms controlling the ECR processes and the factors affecting such treatment were critically reviewed. Subsequently, as a means of restoring passivation of steel embedded in carbonated concrete, such HCP specimens were subjected to ECR. The influence of ECR on the chemistry of the pore solution and the microstructure of the surface and the steel/cement past interface zones were also studied. The main findings of this investigation were as follows: (a) The thickness of the microstructure gradient of cover concrete is significantly decreased with increasing period of water curing but is relatively unaffected by curing temperature, w/e ratio and the use of cement replacement materials. (b) The scratch hardness technique was shown to be potentially useful for characterising the microstructure and microhardness gradients of the surface zone. (c) A relationship between the microstructure gradient and mass transport properties of the surface zone was established. (d) The use of CPF resulted in a significant reduction in porosity of both the cement paste matrix and the aggregate/cement paste transition zone, and a marked improvement in the resistance of the surface zone to carbonation and the ingress of chloride ions. (e) The ECR treatment resulted in a marked densification of the pore structure and in changes to the pore solution chemistry and the cement phases of near-surface and steel/cement paste transition zones. This effect was more pronounced with current density, period of treatment and particularly with the use of sodium phosphate as an electrolyte.

Corrosion inhibitors for the rehabilitation of reinforced concrete

Four corrosion inhibitors namely sodium nitrite, sodium monofluorophosphate, ethanolamine and an alkanolamine-based mixture were studied by immersing mild steel bars for 42 days in model electrolytes of varied pH and chloride concentration which were intended to simulate the pore solution phase present within carbonated and/or chloride-contaminated concrete. Site trials were carried out on sodium monofluorophosphate and the alkanolamine-based inhibitor to study their depth of penetration into concrete. The influence of various carbonating atmospheres on the pore solution chemistry and microstructure of hydrated cement paste was investigated. Physical realkalisation of carbonated cement paste and a calcium nitrite-based corrosion rehabilitation system for chloride-contaminated cement paste were investigated by monitoring ionic transport within the pore solution phase of laboratory specimens. The main findings were as follows: 1,Sodium nitrite, sodium monofluorophosphate, ethanolamine and the alkanolamine-based mixture all behaved as passivating anodic inhibitors of steel corrosion in air-saturated aqueous solutions of varied pH and chloride concentration. 2,Sodium monofluorophosphate failed to penetrate significantly into partially carbonated site concrete when applied as recommended by the supplier. Phosphate and fluoride penetrated 5mm into partially carbonated site concrete treated with sodium monofluorophosphate. 3,The ethanolamine component of the alkanolamine-based inhibitor was found to have penetrated significant depths into partially carbonated site concrete. 4,Carbonating hydrated cement paste over saturated solutions of sodium nitrite resulted in significant concentrations of nitrite in the pore solution of the carbonated paste. Saturated solutions of sodium chloride, ammonium nitrate, magnesium nitrate and sodium dichromate were investigated and identified as alternatives for controlling the relative humidity of the carbonating environment. 5,Hardened carbonated cement paste can by physically realkalised to a limited extent due to the diffusion of hydroxyl ions under saturated conditions. A substantial proportion of the hydroxyl ions that diffused into the carbonated cement paste however, became bound into the cement matrix. Hydroxyl ion concentrations remained below 5mmol/l within the pore solution of the realkalised cement paste. 6, Nitrite ions penetrated significant distances by diffusion within the pore solution of saturated uncarbonated hydrated cement paste.

The pore system and engineering properties of hardened cement paste

The work described in this thesis is an attempt to elucidate the relationships between the pore system and a number of engineering properties of hardened cement paste, particularly tensile strength and resistances to carbonation and ionic penetration. By examining aspects such as the rate of carbonisation, the pore size distribution, the concentration of ions in the pore solution and the phase composition of cement pastes, relationships between the pore system (pores and pore solution) and the resistance to carbonation were investigated. The study was carried out in two parts. First, cement pastes with different pore systems were compared, whilst secondly comparisons were made between the pore systems of cement pastes with different degrees of carbonation. Relationships between the pore structure and ionic penetration were studied by comparing kinetic data relating to the diffusion of various ions in cement pastes with different pore systems. Diffusion coefficients and activation energies for the diffusion process of Cl- and Na+ ions in carbonated and non-carbonated cement pastes were determined by a quasi-steady state technique. The effect of the geometry of pores on ionic diffusion was studied by comparing the mechanisms of ionic diffusion for ions with different radii. In order to investigate the possible relationship between tensile strength and macroporosity, cement paste specimens with cross sectional areas less than 1mm2 were produced so that the chance of a macropore existing within them was low. The tensile strengths of such specimens were then compared with those of larger specimens.

Inorganic surface treatments for concrete protection

Carbonated cement paste surfaces were characterised prior to application of surface treatments. Their chemical and physical properties varied with distance from the surface and method of carbonation. From the surface inwards the pH of expressed pore solutions and porosity were observed to increase. Hardness increased after natural carbonation, but decreased after accelerated carbonation. Generally, accelerated carbonation caused more extreme changes. Investigations were carried out on four concrete surface hardening treatments; two sodium silicates and two silicofluorides. These treatments penetrated and hardened the surface of naturally dried uncarbonated cement paste to a depth fo 250m. Silicofluorides reacted with uncarbonated and carbonated cement pastes to form calcium fluoride. The question of how sodium silicates harden the surface remains unanswered. Surface hardeners do not significantly affect the rate of carbonation, and are unsuitable for re-alkalising carbonated cement paste. Water repellent treatments studied include a silane, a siloxane and a silicone. The silane exhibited the maximum penetration, up to 24mm under favourable conditions, but penetration in all cases was limited by moisture in the substrate. Water repellent treatments slow down water vapour diffusion but, with time, internal moisture levels should reflect external relative humidities. Water repellents may be used to reduce carbonation-induced corrosion where ingress of moisture from intermittent wetting may be slowed. However, treatment with water repellents can temporarily push the carbonation front deeper into the concrete.

Pore structure and diffusional properties of hardened cement pastes

This study has investigated the inclusion of pulverised fuel ash (PFA) and blast furnace slag (BFS) into hardened cement pastes (HCP) in retarding the ingress of chloride ions and oxygen molecules from the external environment. The influence of environmental factors such as drying and carbonation on the pore structure and diffusional properties of OPC, OPC/30%PFA and OPC/65%BFS hardened pastes was investigated. Specimens were desorbed from a saturated surface dry condition to a near constant weight at 65% relative humidity (RH) while others were simultaneously exposed to a 65% RH atmosphere and a carbon dioxide atmosphere of up to 5% by volume until there were fully carbonated. The presence of the interfacial zone at the cement paste-aggregate interface was critically reviewed and identified. The influence of the interfacial zone on porosity and chloride ingress in assumed periodic composites of glass bead mortars was also studied. The investigations have demonstrated the following: (a) The use of fly ash and slag in blended cement pastes has resulted in a marked reduction in capillary porosity and rate of chloride ingress. (b) The ratio of oxygen to chloride diffusion coefficients increased from values close to 1 in permeable pastes, to values of around 15 in low-permeability blended fly ash and slag pastes. This supports the view that the diffusion of chloride ions is retarded by the surface charge of the hydrated cement gel in low-permeability pastes. (c) Compared with plain OPC pastes, the carbonation of blended fly ash and slag pastes resulted in a marked increase in the coarse capillary porosity and a corresponding increase in the oxygen and chloride diffusion rates.

Saccharomyces Cerevisiae as a biotechnological tool for ageing research:studies on translation and metabolism

The yeast Saccharomyces cerevisiae is an important model organism for the study of cell biology. The similarity between yeast and human genes and the conservation of fundamental pathways means it can be used to investigate characteristics of healthy and diseased cells throughout the lifespan. Yeast is an equally important biotechnological tool that has long been the organism of choice for the production of alcoholic beverages, bread and a large variety of industrial products. For example, yeast is used to manufacture biofuels, lubricants, detergents, industrial enzymes, food additives and pharmaceuticals such as anti-parasitics, anti-cancer compounds, hormones (including insulin), vaccines and nutraceuticals. Its function as a cell factory is possible because of the speed with which it can be grown to high cell yields, the knowledge that it is generally recognized as safe (GRAS) and the ease with which metabolism and cellular pathways, such as translation can be manipulated. In this thesis, these two pathways are explored in the context of their biotechnological application to ageing research: (i) understanding translational processes during the high-yielding production of membrane protein drug targets and (ii) the manipulation of yeast metabolism to study the molecule, L-carnosine, which has been proposed to have anti-ageing properties. In the first of these themes, the yeast strains, spt3?, srb5?, gcn5? and yTHCBMS1, were examined since they have been previously demonstrated to dramatically increase the yields of a target membrane protein (the aquaporin, Fps1) compared to wild-type cells. The mechanisms underlying this discovery were therefore investigated. All high yielding strains were shown to have an altered translational state (mostly characterised by an initiation block) and constitutive phosphorylation of the translational initiation factor, eIF2a. The relevance of the initiation block was further supported by the finding that other strains, with known initiation blocks, are also high yielding for Fps1. A correlation in all strains between increased Fps1 yields and increased production of the transcriptional activator protein, Gcn4, suggested that yields are subject to translational control. Analysis of the 5´ untranslated region (UTR) of FPS1 revealed two upstream open reading frames (uORFs). Mutagenesis data suggest that high yielding strains may circumvent these control elements through either a leaky scanning or a re-initiation mechanism. In the second theme, the dipeptide L-carnosine (ß-alanyl-L-histidine) was investigated: it has previously been shown to inhibit the growth of cancer cells but delay senescence in cultured human fibroblasts and extend the lifespan of male fruit flies. To understand these apparently contradictory properties, the effects of L-carnosine on yeast were studied. S. cerevisiae can respire aerobically when grown on a non-fermentable carbon source as a substrate but has a respiro-fermentative metabolism when grown on a fermentable carbon source; these metabolisms mimic normal cell and cancerous cell metabolisms, respectively. When yeast were grown on fermentable carbon sources, in the presence of L-carnosine, a reduction in cell growth and viability was observed, which was not apparent for cells grown on a non-fermentable carbon source. The metabolism-dependent mechanism was confirmed in the respiratory yeast species Pichia pastoris. Further analysis of S. cerevisiae yeast strains with deletions in their nutrient-sensing pathway, which result in an increase in respiratory metabolism, confirmed the metabolism-dependent effects of L-carnosine.

Engineering of a novel Saccharomyces cerevisiae wine strain with a respiratory phenotype at high external glucose concentrations

The recently described respiratory strain Saccharomyces cerevisiae KOY.TM6*P is, to our knowledge, the only reported strain of S. cerevisiae which completely redirects the flux of glucose from ethanol fermentation to respiration, even at high external glucose concentrations (27). In the KOY.TM6*P strain, portions of the genes encoding the predominant hexose transporter proteins, Hxt1 and Hxt7, were fused within the regions encoding transmembrane (TM) domain 6. The resulting chimeric gene, TM6*. encoded a chimera composed of the amino-terminal half of Hxt1 and the carboxy-terminal half of Hxt7. It was subsequently integrated into the genome of an hxt null strain. In this study, we have demonstrated the transferability of this respiratory phenotype to the V5 hxt1-7Δ strain, a derivative of a strain used in enology. We also show by using this mutant that it is not necessary to transform a complete hxt null strain with the TM6* construct to obtain a nonethanol-producing phenotype. The resulting V5.TM6*P strain, obtained by transformation of the V5 hxt1-7Δ strain with the TM6* chimeric gene, produced only minor amounts of ethanol when cultured on external glucose concentrations as high as 5%. Despite the fact that glucose flux was reduced to 30% in the V5.TM6*P strain compared with that of its parental strain, the V5.TM6*P strain produced biomass at a specific rate as high as 85% that of the V5 wild-type strain. Even more relevant for the potential use of such a strain for the production of heterologous proteins and also of low-alcohol beverages is the observation that the biomass yield increased 50% with the mutant compared to its parental strain. Copyright © 2005, American Society for Microbiology. All Rights Reserved.

Supercritical carbonation of calcareous composites:influence of curing

This paper reports the effect of curing on the susceptibility of cementitious composites to carbonation using supercritical carbon dioxide. Samples made using a compression moulding technique were cured in water before and/or after carbonation and the effect on porosity, microstructure, solid phase assemblage and flexural strength was determined. In terms of development of mechanical strength, no benefit was gained from any period of pre- or post-carbonation curing regime. Yet samples cured prior to carbonation underwent minimal chemical reaction between supercritical carbon dioxide and calcium hydroxide, unhydrated cement or C-S-H. Thus there was no correlation between chemical degree of reaction and strength development. The effects responsible for the marked strength gain in supercritically carbonated samples must involve subtle changes in the microstructure of the C-S-H gel, not simple pore filling by calcium carbonate as is often postulated. © 2013 Elsevier Ltd. All rights reserved.\.