Risk assessment in life-cycle costing for road asset management

Queensland Department of Main Roads, Australia, spends approximately A$ 1 billion annually for road infrastructure asset management. To effectively manage road infrastructure, firstly road agencies not only need to optimise the expenditure for data collection, but at the same time, not jeopardise the reliability in using the optimised data to predict maintenance and rehabilitation costs. Secondly, road agencies need to accurately predict the deterioration rates of infrastructures to reflect local conditions so that the budget estimates could be accurately estimated. And finally, the prediction of budgets for maintenance and rehabilitation must provide a certain degree of reliability. This paper presents the results of case studies in using the probability-based method for an integrated approach (i.e. assessing optimal costs of pavement strength data collection; calibrating deterioration prediction models that suit local condition and assessing risk-adjusted budget estimates for road maintenance and rehabilitation for assessing life-cycle budget estimates). The probability concept is opening the path to having the means to predict life-cycle maintenance and rehabilitation budget estimates that have a known probability of success (e.g. produce budget estimates for a project life-cycle cost with 5% probability of exceeding). The paper also presents a conceptual decision-making framework in the form of risk mapping in which the life-cycle budget/cost investment could be considered in conjunction with social, environmental and political issues

The association between fundamental athletic movements and physical fitness in elite junior Australian footballers

This study investigated the associations between fundamental athletic movement and physical fitness in junior Australian football (AF). Forty-four under 18 players performed a fundamental athletic movement assessment consisting of an overhead squat, double lunge, single leg Romanian deadlift and a push up. Movements were scored on three assessment criterions using a three-point scale. Additionally, participants performed five physical fitness tests commonly used for talent identification in AF. A Spearman’s nonparametric correlation matrix was built, with correlation coefficients being visualised using a circularly rendered correlogram. Score on the overhead squat was moderately positively associated with dynamic vertical jump height on left (rs = 0.40; P ≤ 0.05) and right (rs = 0.30; P ≤ 0.05) leg take-off, stationary vertical jump (rs = 0.32; P ≤ 0.05) and negatively associated with 20-m sprint time (rs = −0.35; P ≤ 0.05). Score on the double lunge (left/right side) was moderately positively associated with the same physical fitness tests as well as score on the multistage fitness test. Results suggest that improvements in physical fitness qualities may occur through concurrent increases in fundamental athletic movement skill, namely the overhead squat and double lunge movements. These findings may assist with the identification and development of talent. © 2017 Informa UK Limited, trading as Taylor & Francis Grou

Use of unmanned aerial vehicles (UAVs) for mark-resight nesting population estimation of adult female green sea turtles at Raine Island

Nester abundance is a key measure of the performance of the world's largest green turtle rookery at Raine Island, Australia, and has been estimated by mark-resight counts since 1984. Nesters are first marked by painting their carapace with a longitudinal white stripe. Painted and unpainted turtles are then counted by a surface observer on a small boat in waters adjacent to the reef. Unmanned aerial vehicles (UAV) and underwater video may provide more cost-effective and less biased alternatives to this approach, but estimates must be comparable with historical estimates. Here we compare and evaluate the three methods. We found comparatively little variation in resighting probabilities between consecutive days of sampling or time of day, which supports an underlying assumption of the method (i.e. demographic closure during sampling). This lack of bias in the location availability for detection of painted versus unpainted turtles and further supported by a parallel satellite tracking study of 40 turtles at Raine Island. Our results demonstrated that surface observers consistently reported higher proportions of marked turtles than either the UAV or underwater video method. This in turn yielded higher population estimates with UAV or underwater video compared to the historical surface observer method, which suggested correction factors of 1.53 and 1.73 respectively. We attributed this to observer search error because a white marked turtle is easier to spot than the non-marked turtle. In contrast, the UAV and underwater video methods allowed subsequent frame-by-frame review, thus reducing observer search error. UAVs were the most efficient in terms of survey time, personnel commitment and weather tolerance compared to the other methods. However, underwater video may also be a useful alternative for in-water mark-resight surveys of turtles

Nuance and behavioral cogency: How the Visible Burrow System inspired the Stress-Alternatives Model and conceptualization of the continuum of anxiety

By creating the Visible Burrow System (VBS) Bob Blanchard found a way to study the interaction of genetics, physiology, environment, and adaptive significance in a model with broad validity. The VBS changed the way we think about anxiety and affective disorders by allowing the mechanisms which control them to be observed in a dynamic setting. Critically, Blanchard used the VBS and other models to show how behavioral systems like defense are dependent upon context and behavioral elements unique to the individual. Inspired by the VBS, we developed a Stress Alternatives Model (SAM) to further explore the multifaceted dynamics of the stress response with a dichotomous choice condition. Like the VBS, the SAM is a naturalistic model built upon risk assessment and defensive behavior, but with a choice of response: escape or submission to a large conspecific aggressor. The anxiety of novelty during the first escape must be weighed against fear of the aggressor, and a decision must be made. Both outcomes are adaptively significant, evidenced by a 50/50 split in outcome across several study systems. By manipulating the variables of the SAM, we show that a gradient of anxiety exists that spans the contextual settings of escaping an open field, escaping from aggression, and submitting to aggression. These findings correspond with increasing levels of corticosterone and increasing levels of NPS and BDNF in the central amygdala as the context changes.Whereas some anxiolytics were able to reduce the latency to escape for some animals, only with the potent anxiolytic drug antalarmin (CRF1R-blocker) and the anxiogenic drug yohimbine (α2 antagonist) were we able to reverse the outcome for a substantial proportion of individuals. Our findings promote a novel method for modeling anxiety, offering a distinction between low-and-high levels, and accounting for individual variability. The translational value of the VBS is immeasurable, and it guided us and many other researchers to seek potential clinical solutions through a deeper understanding of regional neurochemistry and gene expression in concert with an ecological behavioral model

A probability method for assessing variability in budget estimates for highway asset management

There are inaccuracies in predicting maintenance and rehabilitation costs for road networks due to the variability and uncertainties in road network condition. To realistically predict maintenance and rehabilitation costs, stochastic characteristics of road network condition should be considered in the estimate. It may, however, not be feasible or practicable to include every single stochastic characteristic of road network conditions in the analysis. To explore this possibility in assessing variations in cost estimates, an analysis was conducted to identify input parameters that are critical for predicting road deterioration condition. Findings indicated that the variability in pavement strength significantly contributed to the variability of predicting road pavement deterioration. Based on this information, discrepancies in cost estimates due to the variability of pavement strength for road maintenance and rehabilitation were subsequently assessed. This paper presents the results of an analysis that was undertaken to identify critical input parameters for road pavement deterioration prediction. The paper also presents a probability method developed for assessing the variation in road maintenance and rehabilitation

Sterol 3β-glucosyltransferase biocatalysts with a range of selectivities, including selectivity for testosterone

The main objectives of this work were to characterise a range of purified recombinant sterol 3β-glucosyltransferases and show that rational sampling of the diversity that exists within sterol 3β-glucosyltransferase sequence space can result in a range of enzyme selectivities. In our study the catalytically active domain of the Saccharomyces cerevisiae 3β-glucosyltransferase was used to mine putative sterol 3β-glucosyltransferases from the databases. Selected diverse sequences were expressed in and purified from Escherichia coli and shown to have different selectivities for the 3β-hydroxysteroids ergosterol and cholesterol. Surprisingly, three enzymes were also selective for testosterone, a 17β-hydroxysteroid. This study therefore reports for the first time sterol 3β-glucosyltransferases with selectivity for both 3β- and 17β-hydroxysteroids and is also the first report of recombinant 3β-glucosyltransferases with selectivity for steroids with a hydroxyl group at positions other than C-3. These enzymes could therefore find utility in the pharmaceutical industry for the green synthesis of a range of glycosylated compounds of medicinal interest

Asynchrony of Gambierdiscus spp. abundance and toxicity in the U.S. Virgin Islands: implications for monitoring and management of Ciguatera

© The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Liefer, J. D., Richlen, M. L., Smith, T. B., DeBose, J. L., Xu, Y., Anderson, D. M., & Robertson, A. Asynchrony of Gambierdiscus spp. abundance and toxicity in the U.S. Virgin Islands: implications for monitoring and management of Ciguatera. Toxins, 13(6), (2021): 413, https://doi.org/10.3390/toxins13060413.Ciguatera poisoning (CP) poses a significant threat to ecosystem services and fishery resources in coastal communities. The CP-causative ciguatoxins (CTXs) are produced by benthic dinoflagellates including Gambierdiscus and Fukuyoa spp., and enter reef food webs via grazing on macroalgal substrates. In this study, we report on a 3-year monthly time series in St. Thomas, US Virgin Islands where Gambierdiscus spp. abundance and Caribbean-CTX toxicity in benthic samples were compared to key environmental factors, including temperature, salinity, nutrients, benthic cover, and physical data. We found that peak Gambierdiscus abundance occurred in summer while CTX-specific toxicity peaked in cooler months (February–May) when the mean water temperatures were approximately 26–28 °C. These trends were most evident at deeper offshore sites where macroalgal cover was highest year-round. Other environmental parameters were not correlated with the CTX variability observed over time. The asynchrony between Gambierdiscus spp. abundance and toxicity reflects potential differences in toxin cell quotas among Gambierdiscus species with concomitant variability in their abundances throughout the year. These results have significant implications for monitoring and management of benthic harmful algal blooms and highlights potential seasonal and highly-localized pulses in reef toxin loads that may be transferred to higher trophic levels.This work was funded in part by the National Oceanic and Atmospheric Administration, Ecology and Oceanography of Harmful Algal Blooms Program (ECOHAB publication number 984) through the CiguaHAB project (NA11NOS4780028), and also contributes to CIGUATOX (NA17NOS4780181) granted to coauthors AR, TBS, DMA, and MLR. Additional support was provided by NSF Partnerships in International Research and Education (1743802), and the Greater Caribbean Center for Ciguatera Research (NIH 1P01ES028949-01 and NSF 1841811). Financial support of YX was from the National Natural Science Foundation of China (41976155), the Natural Science Foundation of Guangxi Province (2020GXNSFDA297001)