700 resultados para Organisational Effectiveness


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In the last decade, Intelligent Transportation Systems (ITS) have increasingly been deployed in work zones by state departments of transportation. Also known as smart work zone systems they improve traffic operations and safety by providing real-time information to travelers, monitoring traffic conditions, and managing incidents. Although there have been numerous ITS deployments in work zones, a framework for evaluating the effectiveness of these deployments does not exist. To justify the continued development and implementation of smart work zone systems, this study developed a framework to determine ITS effectiveness for specific work zone projects. The framework recommends using one or more of five performance measures: diversion rate, delay time, queue length, crash frequency, and speed. The monetary benefits and costs of ITS deployment in a work zone can then be computed using the performance measure values. Such ITS computations include additional considerations that are typically not present in standard benefit-cost computations. The proposed framework will allow for consistency in performance measures across different ITS studies thus allowing for comparisons across studies or for meta analysis. In addition, guidance on the circumstances under which ITS deployment is recommended for a work zone is provided. The framework was illustrated using two case studies: one urban work zone on I-70 and one rural work zone on I-44, in Missouri. The goals of the two ITS deployments were different – the I-70 ITS deployment was targeted at improving mobility whereas the I-44 deployment was targeted at improving safety. For the I-70 site, only permanent ITS equipment that was already in place was used for the project and no temporary ITS equipment was deployed. The permanent DMS equipment serves multiple purposes, and it is arguable whether that cost should be attributed to the work zone project. The data collection effort for the I-70 site was very significant as portable surveillance captured the actual diversion flows to alternative routes. The benefit-cost ratio for the I-70 site was 2.1 to 1 if adjusted equipment costs were included and 6.9 to 1 without equipment costs. The safety-focused I-44 ITS deployment had an estimated benefit-cost ratio of 3.2 to 1.

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BACKGROUND: It is well established that high adherence to HIV-infected patients on highly active antiretroviral treatment (HAART) is a major determinant of virological and immunologic success. Furthermore, psychosocial research has identified a wide range of adherence factors including patients' subjective beliefs about the effectiveness of HAART. Current statistical approaches, mainly based on the separate identification either of factors associated with treatment effectiveness or of those associated with adherence, fail to properly explore the true relationship between adherence and treatment effectiveness. Adherence behavior may be influenced not only by perceived benefits-which are usually the focus of related studies-but also by objective treatment benefits reflected in biological outcomes. METHODS: Our objective was to assess the bidirectional relationship between adherence and response to treatment among patients enrolled in the ANRS CO8 APROCO-COPILOTE study. We compared a conventional statistical approach based on the separate estimations of an adherence and an effectiveness equation to an econometric approach using a 2-equation simultaneous system based on the same 2 equations. RESULTS: Our results highlight a reciprocal relationship between adherence and treatment effectiveness. After controlling for endogeneity, adherence was positively associated with treatment effectiveness. Furthermore, CD4 count gain after baseline was found to have a positive significant effect on adherence at each observation period. This immunologic parameter was not significant when the adherence equation was estimated separately. In the 2-equation model, the covariances between disturbances of both equations were found to be significant, thus confirming the statistical appropriacy of studying adherence and treatment effectiveness jointly. CONCLUSIONS: Our results, which suggest that positive biological results arising as a result of high adherence levels, in turn reinforce continued adherence and strengthen the argument that patients who do not experience rapid improvement in their immunologic and clinical statuses after HAART initiation should be prioritized when developing adherence support interventions. Furthermore, they invalidate the hypothesis that HAART leads to "false reassurance" among HIV-infected patients.

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The objectives of this work were to describe the distribution, density and seasonal variation of the indigenous populations of Rhizobium loti in different Uruguayan soils and to determine the symbiotic effectiveness and stress tolerance factors of different isolates, both with the aim of obtaining selected strains to re-introduce as inoculants in Lotus pastures. R. loti was present in ten soils studied and their densities varied from year to year and within each soil. All the isolates nodulated Lotus corniculatus effectively. The nodules in Lotus pedunculatus and Lotus subbiflorus were small, red on the surface and ineffective in nitrogen fixation. The study of 50 isolates from the ten soils showed high variability in their symbiotic efficiency and tolerance to pH. The indigenous population was acid tolerant in culture medium (pH 4.5), 83% of them could grow at pH 4.5 in 3 days. This work showed that there was a great diversity between the strains of R. loti isolated from Uruguayan soils and supports the importance of selecting among them the most efficient and resistant strains to be included in the inoculants.

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Considering teams as complex adaptive systems (CAS) this study deals with changes in team effectiveness over time in a specific context: professional basketball. The sample comprised 23 basketball teams whose outcomes were analysed over a 12-year period according to two objective measures. The results reveal that all the teams showed chaotic dynamics, one of the key characteristics of CAS. A relationship was also found between teams showing low-dimensional chaotic dynamics and better outcomes, supporting the idea of healthy variability in organizational behaviour. The stability of the squad was likewise found to influence team outcomes, although it was not associated with the chaotic dynamics in team effectiveness. It is concluded that studying teams as CAS enables fluctuations in team effectiveness to be explained, and that the techniques derived from nonlinear dynamical systems, developed specifically for the study of CAS, are useful for this purpose.

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If single case experimental designs are to be used to establish guidelines for evidence-based interventions in clinical and educational settings, numerical values that reflect treatment effect sizes are required. The present study compares four recently developed procedures for quantifying the magnitude of intervention effect using data with known characteristics. Monte Carlo methods were used to generate AB designs data with potential confounding variables (serial dependence, linear and curvilinear trend, and heteroscedasticity between phases) and two types of treatment effect (level and slope change). The results suggest that data features are important for choosing the appropriate procedure and, thus, inspecting the graphed data visually is a necessary initial stage. In the presence of serial dependence or a change in data variability, the Nonoverlap of All Pairs (NAP) and the Slope and Level Change (SLC) were the only techniques of the four examined that performed adequately. Introducing a data correction step in NAP renders it unaffected by linear trend, as is also the case for the Percentage of Nonoverlapping Corrected Data and SLC. The performance of these techniques indicates that professionals" judgments concerning treatment effectiveness can be readily complemented by both visual and statistical analyses. A flowchart to guide selection of techniques according to the data characteristics identified by visual inspection is provided.

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SummaryThe alcohol use of adolescents and young adults is one of the world's most important and costliest health problems. Particularly, binge drinking (i.e. drinking an important amount of alcohol in one occasion) among young people increase the risk of detrimental consequences such as blackouts, injuries, at-risk sexual behaviors, involvement in violent acts, academic failure, and suicide attempts. In countries with mandatory conscription mechanisms, such as Switzerland, the army provides a unique opportunity to reach a large portion of this high risk population. We used this sample to evaluate the prevalence of binge drinking among young men, to test the efficacy of brief motivational interventions (BMI) as a primary and secondary preventive measure, and to examine the mechanisms underlying BMI in this age group.We showed that binge drinking among young French-speaking Swiss men is less of an exception than it is the norm. Of those using alcohol, 75.5% had a binge drinking episode at least monthly, and 69.3% of all consumption reported in a one-week diary was due to binge drinking days.We used two different inclusion modes to evaluate the success of alcohol BMI. In the first randomized controlled trial, inclusion relied on a random selection of conscripts. BMI efficacy was evaluated in a sample of conscripts who visited the army recruitment centre that is potentially generalizable to the entire population. In the second randomized controlled trial, we included subjects voluntarily participating in BMI. This venue might be more realistic for young adults; it is more akin to the MI spirit, in which it is crucial for individuals to control their own decisions.Regarding BMI efficacy as a secondary prevention measure (i.e. to help decrease alcohol use among at-risk drinkers, defined here as those having a binge drinking episode at least monthly), it was effective among randomly selected at-risk drinkers, whereas it was not effective among at-risk drinkers who voluntarily showed up. Individuals who showed interest in BMI had more severe patterns of alcohol use, which may have made change more difficult and calls for treatment that is more intensive. BMI demonstrated a 20% reduction in weekly alcohol use among randomly selected participants, indicating potential interest in BMI implementation within similar community settings.Regarding BMI efficacy as a primary prevention measure (i.e. to help maintain low levels of use among low-risk drinkers), it had significant protective effects among low-risk drinkers voluntarily showing up whereas it was not effective among low-risk drinkers randomly selected. This suggests that BMI might help young individuals keep their drinking at low levels, especially when they are interested in discussing their alcohol use. Therefore, BMI has potentially promising uses in primary prevention efforts. The content of these interventions for low-risk drinkers who do not seek BMI on their own should be further evaluated.BMI mechanisms were addressed since little is known about exactly which elements of it work, or which of the counselor and subject communication behaviors are most effective in triggering behavior changes. The causal chain hypothesis developed in the motivational interviewing (MI) theory was followed, and it was found that counselor behaviors consistent with the MI approach (MICO) were significantly more likely to be followed by participant language in favor of change (change talk, CT), while behaviors inconsistent with MI (MIIN) were significantly less likely to do so. Several CT dimensions measured during BMI (particularly Ability, Desire, and Need to change) were predictive of change in alcohol use. Our findings lend strong support for the use of MICO behaviors and the avoidance of MIIN behaviors in eliciting CT, and point out that particular attention should be paid to the utterances in several sub-dimensions of CT and to the strength of expression, since these are good indicators of potential actual behavior change in future.RésuméLa consommation d'alcool chez les adolescents et les jeunes adultes est un des problèmes de santé les plus importants et les plus coûteux dans le monde. En particulier, les consommations importantes d'alcool en une occasion (binge drinking) parmi les jeunes adultes ont été liées à des conséquences telles que pertes de connaissance, accidents et blessures, comportements sexuels à risque, violences, difficultés scolaires et tentatives de suicide. Les pays qui, comme la Suisse, connaissent un processus de recrutement obligatoire pour l'armée offrent une opportunité unique d'atteindre une large portion de cette population à hauts risques. Nous avons utilisé cet échantillon pour évaluer la prévalence du binge drinking parmi les jeunes hommes, pour tester l'efficacité de l'intervention brève motivationnelle (IBM) comme mesure de prévention primaire et secondaire, et pour examiner les mécanismes sous-tendant ce type d'interventions.La première partie de cette étude montre que le binge drinking est moins une exception que la norme parmi les jeunes hommes suisses francophones. 75.5% des personnes consommant de l'alcool avaient au moins un épisode de binge drinking par mois et 69.3% du total des boissons alcoolisées reportées comme consommation de la semaine précédant le questionnaire avaient été consommées lors d'épisodes de binge drinking.Pour évaluer l'efficacité de l'IBM dans ce cadre, nous avons utilisé deux modes d'inclusion. Dans une première étude randomisée contrôlée, nous avons inclus des personnes sélectionnées au hasard parmi toutes celles se présentant au centre de recrutement, créant ainsi un groupe potentiellement représentatif de l'ensemble du collectif. Dans la deuxième étude randomisée contrôlée, nous avons inclus des sujets se présentant volontairement pour recevoir une IBM, prendre des volontaires pouvant être plus proche de la réalité et plus proche de l'esprit motivationnel dans lequel il est crucial que l'individu contrôle ses décisions.En regardant l'IBM comme mesure de prévention secondaire (c'est-à-dire aider à diminuer la consommation d'alcool chez les consommateurs à risque, définis ici comme au moins un épisode de binge drinking par mois), l'IBM était efficace lorsque les participants étaient inclus au hasard et inefficace lorsqu'ils étaient volontaires. Les jeunes hommes volontaires pour un IBM avaient un mode de consommation particulièrement sévère qui pourrait être plus difficile à changer et nécessiter un traitement plus intensif. Parmi les personnes sélectionnées au hasard, l'IBM permettait une diminution de 20% de la consommation hebdomadaire d'alcool, montrant l'intérêt potentiel d'une implémentation de ce type de mesures dans des contextes communautaires similaires.En ce qui concerne l'IBM comme mesure de prévention primaire (c'est-à-dire aider à maintenir une consommation à bas risque chez les consommateurs à bas risque), l'IBM avaient un effet protectif significatif parmi les jeunes hommes volontaires pour une IBM, mais pas d'effet chez ceux sélectionnés au hasard. Ces résultats suggèrent que l'IBM pourrait aider de jeunes personnes à maintenir un niveau de consommation à bas risque si celles-ci s'intéressent à discuter cette consommation et aurait ainsi un potentiel intéressant comme mesure de prévention primaire. Le contenu de l'IBM pour des consommateurs à bas risque non-volontaires pour une IBM devra encore être évalué.Nous avons ensuite examiné les mécanismes de l'IBM car son fonctionnement est encore peu expliqué et les comportements de l'intervenant et du sujet les plus à même de provoquer le changement ne sont pas bien définis. En suivant l'hypothèse d'une chaine causale développée dans la littérature de l'entretien motivationnel (EM), nous avons pu montrer qu'un discours en faveur du changement chez le sujet était plus probable après des comportements de l'intervenant recommandés dans l'EM et moins probable après des comportements à éviter dans l'EM ; et que plusieurs dimensions de ce discours en faveur du changement (notamment la capacité, le désir et le besoin de changer) prédisaient un changement effectif dans la consommation d'alcool. Ces résultats encouragent donc à utiliser des comportements recommandés dans l'EM pour favoriser un discours en faveur du changement. Ils montrent aussi qu'une attention particulière doit être portée à la fréquence et à la force avec laquelle sont exprimées certaines dimensions de ce discours car ceux-ci indiquent un potentiel changement effectif de comportement.Résumé vulgariséLa consommation d'alcool chez les adolescents et les jeunes adultes est un des problèmes de santé les plus importants et les plus coûteux dans le monde. En particulier, les consommations importantes d'alcool en une occasion (binge drinking) parmi les jeunes adultes augmentent fortement les risques de conséquences telles que pertes de connaissance, accidents et blessures, comportements sexuels à risque, violences, difficultés scolaires et tentatives de suicide. Les pays qui, comme la Suisse, connaissent un processus de recrutement obligatoire pour l'armée offrent une opportunité unique d'atteindre une large portion de cette population à hauts risques. Nous avons utilisé cet échantillon pour évaluer l'importance du phénomène de binge drinking, pour tester l'efficacité de l'intervention brève motivationnelle (IBM) comme mesure de prévention de la consommation à risque d'alcool, et pour examiner comment fonctionne ce type d'interventions.La première partie de cette étude montre que le binge drinking est moins une exception que la norme parmi les jeunes hommes suisses francophones. Trois quart des personnes consommant de l'alcool avaient au moins un épisode de binge drinking par mois. Presque 70% du total des boissons alcoolisées consommées durant la semaine précédant le questionnaire avaient été consommées lors d'épisodes de binge drinking.Nous avons ensuite mené deux études pour évaluer l'efficacité de l'IBM dans ce cadre. Dans une première étude, nous avons sélectionné des personnes au hasard parmi toutes celles se présentant au centre de recrutement, créant ainsi un groupe potentiellement représentatif de l'ensemble du collectif. Dans la deuxième étude, nous avons inclus toutes les personnes se présentant volontairement pour recevoir une IBM, prendre des volontaires pouvant être plus proche de la réalité et plus proche de l'approche motivationnelle dans laquelle il est crucial que l'individu contrôle ses décisions. Dans les deux études, nous testions l'efficacité de l'IBM comme mesure de prévention primaire et secondaire (voir ci-dessous).En regardant l'IBM comme mesure de prévention secondaire (c'est-à-dire aider à diminuer la consommation d'alcool chez les consommateurs à risque, définis ici comme au moins un épisode de binge drinking par mois), l'IBM était efficace lorsque les participants étaient inclus au hasard et inefficace lorsqu'ils étaient volontaires. Les jeunes hommes volontaires pour un IBM avaient un mode de consommation particulièrement sévère qui pourrait être plus difficile à changer et nécessiter un traitement plus intensif. Parmi les personnes sélectionnées au hasard, l'IBM permettait une diminution de 20% de la consommation hebdomadaire d'alcool, montrant l'intérêt potentiel de la mise en place de ce type de mesures dans des contextes communautaires similaires.En ce qui concerne l'IBM comme mesure de prévention primaire (c'est-à-dire aider à maintenir une consommation à bas risque chez les consommateurs à bas risque), l'IBM avaient un effet protectif parmi les jeunes hommes volontaires pour une IBM, mais pas d'effet chez ceux sélectionnés au hasard. Ces résultats suggèrent que l'IBM pourrait aider de jeunes personnes à maintenir un niveau de consommation à bas risque si celles-ci s'intéressent à discuter de cette consommation. Le contenu de l'IBM pour des consommateurs à bas risque non-volontaires pour une IBM devra encore être évalué.Nous avons ensuite examiné le fonctionnement de l'IBM et cherché quels comportements de l'intervenant et du jeune homme pouvaient être les plus à même d'amener à un changement dans la consommation. Nous avons pu montrer que 1) un discours en faveur du changement chez le jeune homme était plus probable après des comportements de l'intervenant recommandés dans l'approche motivationnelle et moins probable après des comportements non-recommandés ; et 2) plusieurs dimensions de ce discours en faveur du changement (notamment la capacité, le désir et le besoin de changer) prédisaient un changement effectif dans la consommation d'alcool. Ces résultats encouragent donc à utiliser des comportements recommandés dans l'EM pour favoriser un discours en faveur du changement. Ils montrent aussi qu'une attention particulière doit être portée à certaines dimensions de ce discours car celles-ci indiquent un potentiel changement effectif de comportement.

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Rumble strips are patches of specially treated pavement surfaces which are designed to produce aural and tactile stimuli inside vehicles. The intent is to alert drivers and when desirable, cause them to slow down or come to a stop. Installations were made in a three-county area in Iowa to study rumble strip effectiveness as an accident reducing measure. The investigation of accidents at the various test sites showed that rumble strips were effective in reducing certain types of intersection accidents. Although no statistically significant effect of the saturation use was found on total accidents, there are indications that accidents may be reduced when used in low density i.e., rural type areas.

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OBJECTIVE: To examine the incremental cost effectiveness of the five first line pharmacological smoking cessation therapies in the Seychelles and other developing countries. DESIGN: A Markov chain cohort simulation. SUBJECTS: Two simulated cohorts of smokers: (1) a reference cohort given physician counselling only; (2) a treatment cohort given counselling plus cessation therapy. INTERVENTION: Addition of each of the five pharmacological cessation therapies to physician provided smoking cessation counselling. MAIN OUTCOME MEASURES: Cost per life-year saved (LYS) associated with the five pharmacotherapies. Effectiveness expressed as odds ratios for quitting associated with pharmacotherapies. Costs based on the additional physician time required and retail prices of the medications. RESULTS: Based on prices for currently available generic medications on the global market, the incremental cost per LYS for a 45 year old in the Seychelles was 599 US dollars for gum and 227 dollars for bupropion. Assuming US treatment prices as a conservative estimate, the incremental cost per LYS was significantly higher, though still favourable in comparison to other common medical interventions: 3712 dollars for nicotine gum, 1982 dollars for nicotine patch, 4597 dollars for nicotine spray, 4291 dollars for nicotine inhaler, and 1324 dollars for bupropion. Cost per LYS increased significantly upon application of higher discount rates, which may be used to reflect relatively high opportunity costs for health expenditures in developing countries with highly constrained resources and high overall mortality. CONCLUSION: Pharmacological cessation therapy can be highly cost effective as compared to other common medical interventions in low mortality, middle income countries, particularly if medications can be procured at low prices.

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Traffic noise monitoring using FHWA's Demonstration Projects Division Mobile Noise Laboratory at free field, single wall and parallel barrier site on I-380 in Evansdale, Iowa is described. Access to I-380 prior to its being open to traffic afforded a controlled pass-by monitoring phase involving different vehicle types. A subsequent second phase entailed identical measurement methodology to monitor "real world" I-380 traffic noise. Phase I data indicated increases in noise were significant under the parallel barrier conditions for light duty vehicles operating in the far lane. Phase II results showed that the actual I-380 traffic mix largely offset the earlier observed effect, but minor increases in traffic noise under the parallel system were noted. These differences in noise barrier system effectiveness are judged to be insignificant at this particular study location.

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Forensic science is increasingly relied upon by law enforcement to assist in solvingcrime and gaining convictions, and by the judicial system in the adjudication ofspecific criminal cases. However, the value of forensic science relative to the workinvolved and the outcome of cases has yet to be established in the Australiancontext. Previous research in this area has mainly focused on the science andtechnology, rather than examining how people can use forensic services/science tothe best possible advantage to produce appropriate justice outcomes. This fiveyearproject entails an investigation into the effectiveness of forensic science inpolice investigations and court trials. It aims to identify when, where and howforensic science can add value to criminal investigations, court trials and justiceoutcomes while ensuring the efficient use of available resources initially in theVictorian and the ACT criminal justice systems and ultimately across Australiaand New Zealand. This paper provides an overview of the rationale and aims ofthe research project and discusses current work-in-progress.

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Background: Computer assisted cognitive remediation (CACR) was demonstrated to be efficient in improving cognitive deficits in adults with psychosis. However, scarce studies explored the outcome of CACR in adolescents with psychosis or at high risk. Aims: To investigate the effectiveness of a computer-assisted cognitive remediation (CACR) program in adolescents with psychosis or at high risk. Method: Intention to treat analyses included 32 adolescents who participated in a blinded 8-week randomized controlled trial of CACR treatment compared to computer games (CG). Cognitive abilities, symptoms and psychosocial functioning were assessed at baseline and posttreatment. Results: Improvement in visuospatial abilities was significantly greater in the CACR group than in CG. Other cognitive functions, psychotic symptoms and psychosocial functioning improved significantly, but at similar rates, in the two groups. Conclusion: CACR can be successfully administered in this population; it proved to be effective over and above CG for the most intensively trained cognitive ability.

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BACKGROUND: There is increasing interest in provision of essential surgical care as part of public health policy in low- and middle-income countries (LMIC). Relatively simple interventions have been shown to prevent death and disability. We reviewed the published literature to examine the cost-effectiveness of simple surgical interventions which could be made available at any district hospital, and compared these to standard public health interventions. METHODS: PubMed and EMBASE were searched using single and combinations of the search terms "disability adjusted life year" (DALY), "quality adjusted life year," "cost-effectiveness," and "surgery." Articles were included if they detailed the cost-effectiveness of a surgical intervention of relevance to a LMIC, which could be made available at any district hospital. Suitable articles with both cost and effectiveness data were identified and, where possible, data were extrapolated to enable comparison across studies. RESULTS: Twenty-seven articles met our inclusion criteria, representing 64 LMIC over 16 years of study. Interventions that were found to be cost-effective included cataract surgery (cost/DALY averted range US$5.06-$106.00), elective inguinal hernia repair (cost/DALY averted range US$12.88-$78.18), male circumcision (cost/DALY averted range US$7.38-$319.29), emergency cesarean section (cost/DALY averted range US$18-$3,462.00), and cleft lip and palate repair (cost/DALY averted range US$15.44-$96.04). A small district hospital with basic surgical services was also found to be highly cost-effective (cost/DALY averted 1 US$0.93), as were larger hospitals offering emergency and trauma surgery (cost/DALY averted US$32.78-$223.00). This compares favorably with other standard public health interventions, such as oral rehydration therapy (US$1,062.00), vitamin A supplementation (US$6.00-$12.00), breast feeding promotion (US$930.00), and highly active anti-retroviral therapy for HIV (US$922.00). CONCLUSIONS: Simple surgical interventions that are life-saving and disability-preventing should be considered as part of public health policy in LMIC. We recommend an investment in surgical care and its integration with other public health measures at the district hospital level, rather than investment in single disease strategies.

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The effects of diethylenetriaminpenta(methylenephosphonic acid) (DTPMP), a phosphonate inhibitor, on the growth of delayed ettringite have been evaluated using concrete in highway US 20 near Williams, Iowa, and the cores of six highways subject to moderate (built in 1992) or minor (built in 1997) deterioration. Application of 0.01 and 0.1 vol. % DTPMP to cores was made on a weekly or monthly basis for one year under controlled laboratory-based freeze-thaw and wet-dry conditions over a temperature range of -15 degrees to 58 degrees C to mimic extremes in Iowa roadway conditions. The same concentrations of phosphonate were also applied to cores left outside (roof of Science I at Iowa State University) over the same period of time. Nineteen applications of 0.1 vol. % DTPMP with added deicing salt solution (about 23 weight % NACL) were made to US 20 during the winters of 2003 and 2004. In untreated samples, air voids, pores, and occasional cracks are lined with acicular ettringite crystals (up to 50 micrometers in length) whereas air voids, pores, and cracks in concrete from the westbound lane of US 20 are devoid of ettringite up to a depth of about 0.5 mm from the surface of the concrete. Ettringite is also absent in zones up to 6 mm from the surface of concrete slabs placed on the roof of Science I and cores subject to laboratory-based freeze-thaw experiments. In these zones, the relatively high concentration of DTPMP caused it to behave as a chelator. Stunted ettringite crystals 5 to 25 micrometers in length, occasionally coated with porlandite, form on the margins of these zones indicating that in these areas DTPMP behaved as an inhibitor due to a reduction in the concentration of phosphonate. Analyses of mixes of ettringite and DTPMP using electrospray mass spectrometry suggests that the stunting of ettringite growth is caused by the adsorption of a Ca2+ ion and a water molecule to deprotonated DTPMP on the surface of the {0001} face of ettringite. It is anticipated that by using a DTPMP concentration of between 0.001 and 0.01 vol. % for the extended life of a highway (i.e. >20 years), deterioration caused by the expansive growth of ettringite will be markedly reduced.