Design, Construction, and Preliminary Investigations of Otta Seal in Iowa

Faced with limited financial resources, pavement engineers constantly seek more durable and economical technologies for road preservations and rehabilitations. Consequently, there have been many efforts to study resurfacing strategies, including various types of sealing for local roads. Among different sealing methodologies, Otta seal is a technique that has not yet been sufficiently studied in the U.S.A. For this investigation, the first Otta seal site in the state of Iowa was constructed using a double-layer Otta seal design over 6.4 km of cracked asphalt pavement. Otta seal design and construction details are documented and discussed, and test sections using various aggregates are compared for performance. The key lesson learned was that proper aggregate selection within gradation limits and aggregate spread rates were critical factors for Otta seal performance. Otta seal capability for holding loose aggregate particles and for dust control were examined, and there were indications that excessive proportion of fine aggregate particles could lead to diminished performance associated with fugitive dust emissions and unbound aggregate particles. Although the Otta seal provided a smooth surface satisfying road user and agency requirements, it did not significantly add structural capacity to the existing asphalt pavement. The findings from this study will benefit road officials and other decision makers who need to consider alternatives for resurfacing distressed low-volume asphalt roads. Low-volume roads represent a large proportion of the route mileage of the transportation infrastructure system, and the cost to secondary road departments of maintaining such roads can be quite important. Over time, Otta seal has exhibited reduced maintenance costs by providing a typical service life of 8 to 12 years for a single-layer Otta seal, compared with 4 to 6 years for single-layer chip seal (1–3). Norway-based Otta seal (graded aggregate) technology, originally developed in the 1960s and used in Scandinavian countries, Africa, and other continents, is an economical and practical alternative to traditional bituminous surface treatments (BSTs). It provides flexible, durable, and impervious surfacing that is more tolerant of higher anticipated pavement deflections on low-volume roads that are sometimes constructed with lower-quality materials (4). Compared with traditional BSTs requiring high-quality materials and specialized expertise, Otta seal can often be constructed using more economical local aggregates and readily available equipment (asphalt distributor, aggregate spreader, pneumatic-tired roller, and mechanical broom) typically used for asphalt maintenance (4). Otta seal, formed by a thin bituminous surface treatment (BST) of graded aggregates, ranging from natural gravel to crushed stone, with a relatively low-viscosity binder, relies on a combination of mechanical particle interlock and the binding effect of asphalt binder to provide a resilient, waterproof membrane over the road surface. The state of South Dakota completed its first Otta seal project in Day County in 2008 to provide a low-cost surface using in-house resources and equipment in place of a standard hot-mix asphalt (HMA) pavement surface (5). Various agencies (city, county, and state department of transportation) in Minnesota have also applied Otta seal for traffic volumes ranging from 100 up to 2,000 vehicles average daily traffic (ADT) since early 2000 (6, 7). Most road sections surfaced with Otta seal in Minnesota have performed well except when they encountered unexpected situations such as unanticipated high traffic volumes or flood damage during their service lives (7). Otta seal construction was also found reasonably affordable compared with HMA or Portland cement concrete (PCC) pavement systems for use on low-volume roads; Otta seal has been considered a cost-effective and durable approach to dust control for gravel roads. In particular for developing countries, the available evidence suggests that Otta seal, surface dressings, and Cape seal are the most cost-effective and durable forms of dust control in relation to life-cycle costs (8–10). The Norwegian Public Roads Administration (NPRA) Guideline 93 (4) was compiled using empirical data and experience from many trials and full-scale projects worldwide. However, in the U.S.A., few states have used the Otta seal, and hence, it is felt that a more comprehensive research along with full documentation is necessary to assist in the implementation of Otta seals in Iowa and many other states in the U.S.A

Unpacking the behavioural components and delivery features of early childhood obesity prevention interventions in the TOPCHILD Collaboration: a systematic review and intervention coding protocol.

INTRODUCTION: Little is known about how early (eg, commencing antenatally or in the first 12 months after birth) obesity prevention interventions seek to change behaviour and which components are or are not effective. This study aims to (1) characterise early obesity prevention interventions in terms of target behaviours, delivery features and behaviour change techniques (BCTs), (2) explore similarities and differences in BCTs used to target behaviours and (3) explore effectiveness of intervention components in preventing childhood obesity. METHODS AND ANALYSIS: Annual comprehensive systematic searches will be performed in Epub Ahead of Print/MEDLINE, Embase, Cochrane (CENTRAL), CINAHL, PsycINFO, as well as clinical trial registries. Eligible randomised controlled trials of behavioural interventions to prevent childhood obesity commencing antenatally or in the first year after birth will be invited to join the Transforming Obesity in CHILDren Collaboration. Standard ontologies will be used to code target behaviours, delivery features and BCTs in both published and unpublished intervention materials provided by trialists. Narrative syntheses will be performed to summarise intervention components and compare applied BCTs by types of target behaviours. Exploratory analyses will be undertaken to assess effectiveness of intervention components. ETHICS AND DISSEMINATION: The study has been approved by The University of Sydney Human Research Ethics Committee (project no. 2020/273) and Flinders University Social and Behavioural Research Ethics Committee (project no. HREC CIA2133-1). The study's findings will be disseminated through peer-reviewed publications, conference presentations and targeted communication with key stakeholders. PROSPERO REGISTRATION NUMBER: CRD42020177408

Transforming Obesity Prevention for CHILDren (TOPCHILD) Collaboration: protocol for a systematic review with individual participant data meta-analysis of behavioural interventions for the prevention of early childhood obesity.

INTRODUCTION: Behavioural interventions in early life appear to show some effect in reducing childhood overweight and obesity. However, uncertainty remains regarding their overall effectiveness, and whether effectiveness differs among key subgroups. These evidence gaps have prompted an increase in very early childhood obesity prevention trials worldwide. Combining the individual participant data (IPD) from these trials will enhance statistical power to determine overall effectiveness and enable examination of individual and trial-level subgroups. We present a protocol for a systematic review with IPD meta-analysis to evaluate the effectiveness of obesity prevention interventions commencing antenatally or in the first year after birth, and to explore whether there are differential effects among key subgroups. METHODS AND ANALYSIS: Systematic searches of Medline, Embase, Cochrane Central Register of Controlled Trials, Cumulative Index to Nursing and Allied Health Literature (CINAHL), PsycInfo and trial registries for all ongoing and completed randomised controlled trials evaluating behavioural interventions for the prevention of early childhood obesity have been completed up to March 2021 and will be updated annually to include additional trials. Eligible trialists will be asked to share their IPD; if unavailable, aggregate data will be used where possible. An IPD meta-analysis and a nested prospective meta-analysis will be performed using methodologies recommended by the Cochrane Collaboration. The primary outcome will be body mass index z-score at age 24±6 months using WHO Growth Standards, and effect differences will be explored among prespecified individual and trial-level subgroups. Secondary outcomes include other child weight-related measures, infant feeding, dietary intake, physical activity, sedentary behaviours, sleep, parenting measures and adverse events. ETHICS AND DISSEMINATION: Approved by The University of Sydney Human Research Ethics Committee (2020/273) and Flinders University Social and Behavioural Research Ethics Committee (HREC CIA2133-1). Results will be relevant to clinicians, child health services, researchers, policy-makers and families, and will be disseminated via publications, presentations and media releases. PROSPERO REGISTRATION NUMBER: CRD42020177408

Transforming Obesity Prevention for CHILDren (TOPCHILD) Collaboration: protocol for a systematic review with individual participant data meta-analysis of behavioural interventions for the prevention of early childhood obesity

Introduction Behavioural interventions in early life appear to show some effect in reducing childhood overweight and obesity. However, uncertainty remains regarding their overall effectiveness, and whether effectiveness differs among key subgroups. These evidence gaps have prompted an increase in very early childhood obesity prevention trials worldwide. Combining the individual participant data (IPD) from these trials will enhance statistical power to determine overall effectiveness and enable examination of intervention-covariate interactions. We present a protocol for a systematic review with IPD meta-analysis to evaluate the effectiveness of obesity prevention interventions commencing antenatally or in the first year after birth, and to explore whether there are differential effects among key subgroups

Unpacking the behavioural components and delivery features of early childhood obesity prevention interventions in the TOPCHILD Collaboration: a systematic review and intervention coding protocol

Introduction Little is known about how early (e.g., commencing antenatally or in the first 12 months after birth) obesity prevention interventions seek to change behaviour and which components are or are not effective. This study aims to 1) characterise early obesity prevention interventions in terms of target behaviours, delivery features, and behaviour change techniques (BCTs), 2) explore similarities and differences in BCTs used to target behaviours, and 3) explore effectiveness of intervention components in preventing childhood obesity

Design, Construction, and Preliminary Investigations of Otta Seal in Iowa

Faced with limited financial resources, pavement engineers constantly seek more durable and economical technologies for road preservations and rehabilitations. Consequently, there have been many efforts to study resurfacing strategies, including various types of sealing for local roads. Among different sealing methodologies, Otta seal is a technique that has not yet been sufficiently studied in the U.S.A. For this investigation, the first Otta seal site in the state of Iowa was constructed using a double-layer Otta seal design over 6.4 km of cracked asphalt pavement. Otta seal design and construction details are documented and discussed, and test sections using various aggregates are compared for performance. The key lesson learned was that proper aggregate selection within gradation limits and aggregate spread rates were critical factors for Otta seal performance. Otta seal capability for holding loose aggregate particles and for dust control were examined, and there were indications that excessive proportion of fine aggregate particles could lead to diminished performance associated with fugitive dust emissions and unbound aggregate particles. Although the Otta seal provided a smooth surface satisfying road user and agency requirements, it did not significantly add structural capacity to the existing asphalt pavement. The findings from this study will benefit road officials and other decision makers who need to consider alternatives for resurfacing distressed low-volume asphalt roads. Low-volume roads represent a large proportion of the route mileage of the transportation infrastructure system, and the cost to secondary road departments of maintaining such roads can be quite important. Over time, Otta seal has exhibited reduced maintenance costs by providing a typical service life of 8 to 12 years for a single-layer Otta seal, compared with 4 to 6 years for single-layer chip seal (1–3). Norway-based Otta seal (graded aggregate) technology, originally developed in the 1960s and used in Scandinavian countries, Africa, and other continents, is an economical and practical alternative to traditional bituminous surface treatments (BSTs). It provides flexible, durable, and impervious surfacing that is more tolerant of higher anticipated pavement deflections on low-volume roads that are sometimes constructed with lower-quality materials (4). Compared with traditional BSTs requiring high-quality materials and specialized expertise, Otta seal can often be constructed using more economical local aggregates and readily available equipment (asphalt distributor, aggregate spreader, pneumatic-tired roller, and mechanical broom) typically used for asphalt maintenance (4). Otta seal, formed by a thin bituminous surface treatment (BST) of graded aggregates, ranging from natural gravel to crushed stone, with a relatively low-viscosity binder, relies on a combination of mechanical particle interlock and the binding effect of asphalt binder to provide a resilient, waterproof membrane over the road surface. The state of South Dakota completed its first Otta seal project in Day County in 2008 to provide a low-cost surface using in-house resources and equipment in place of a standard hot-mix asphalt (HMA) pavement surface (5). Various agencies (city, county, and state department of transportation) in Minnesota have also applied Otta seal for traffic volumes ranging from 100 up to 2,000 vehicles average daily traffic (ADT) since early 2000 (6, 7). Most road sections surfaced with Otta seal in Minnesota have performed well except when they encountered unexpected situations such as unanticipated high traffic volumes or flood damage during their service lives (7). Otta seal construction was also found reasonably affordable compared with HMA or Portland cement concrete (PCC) pavement systems for use on low-volume roads; Otta seal has been considered a cost-effective and durable approach to dust control for gravel roads. In particular for developing countries, the available evidence suggests that Otta seal, surface dressings, and Cape seal are the most cost-effective and durable forms of dust control in relation to life-cycle costs (8–10). The Norwegian Public Roads Administration (NPRA) Guideline 93 (4) was compiled using empirical data and experience from many trials and full-scale projects worldwide. However, in the U.S.A., few states have used the Otta seal, and hence, it is felt that a more comprehensive research along with full documentation is necessary to assist in the implementation of Otta seals in Iowa and many other states in the U.S.A.This is a manuscript of an article published as Gushgari, Sharif Y., Yang Zhang, Ali Nahvi, Halil Ceylan, Sunghwan Kim, Ali Arabzadeh, Charles T. Jahren, and Charles Øverby. "Design, Construction, and Preliminary Investigations of Otta Seal in Iowa." Transportation Research Record (2019). DOI: 10.1177%2F0361198119853567. Posted with permission.</p