The use of otolith morphology to indicate the stock structure of common coral trout (Plectropomus leopardus) on the Great Barrier Reef, Australia

We investigated the use of otolith morphology to indicate the stock structure of an exploited serranid coral reef fish, Plectropomus leopardus, on the Great Barrier Reef (GBR), Australia. Otoliths were measured by traditional one-and two-dimensional measures (otolith length, width, area, perimeter, circularity, and rectangularity), as well as by Fourier analysis to capture the finer details of otolith shape. Variables were compared among four regions of the GBR separated by hundreds of kilometers, as well as among three reefs within each region, hundreds of meters to tens of kilometers apart. The temporal stability in otolith structure was examined by comparing two cohorts of fully recruited four-year-old P. leopardus collected two years before and two years after a signif icant disturbance in the southern parts of the GBR caused by a large tropical cyclone in March 1997. Results indicated the presence of at least two stocks of P. leopardus, although the structure of each stock varied depending on the cohort considered. The results highlight the importance of incorporating data from several years in studies using otolith morphology to discriminate temporary and possibly misleading signals from those that indicate persistent spatial structure in stocks. We conclude that otolith morphology can be used as an initial step to direct further research on groups of P. leopardus that have lived at least a part of their life in different environments

Detection of Dissimulation in Children on the BASC-2 Self-Report of Personality

Children are capable of deliberately distorting or misrepresenting psychological symptoms on self-reports of behavior and personality, which is referred to as dissimulation. Malingering and defensiveness are two forms of dissimulation that involve exaggerating symptoms or denying symptoms, respectively. The purpose of this study was to examine the extent to which the Behavior Assessment System for Children-2 Self-Report of Personality validity scales identified dissimulation response styles in children. This investigation employed a between-subjects experimental simulation design with three conditions. One hundred and eighteen children were randomly assigned to a control group or to one of two simulation groups: (a) a malingering group to simulate behavioral and emotional symptoms, or (b) a defensive group to simulate minimization or denial of behavioral and emotional symptoms. Specific research questions addressed whether the validity scales were useful in signaling caution for children who were instructed to malinger and for children who were instructed to respond defensively. Findings suggested that the F Index is most sensitive to detecting malingering. Results also indicated that the L Index may be a useful indicator of malingering, but this scale did not perform as well as expected in detecting children who were instructed to respond defensively

A bioassay for cyclophosphamide in blood, lung and tumour.

A bioassay has been developed to detect and quantify the concentration of cytotoxic metabolites of cyclophosphamide (CY) in blood, tumour, and lungs of mice. Extracts were made of blood or solid tissues taken from mice given CY and these were used to treat log phase Chinese Hamster V79 cells in culture for up to 24 h. The amount of cell killing was tested by colony formation 7 days later. The effects of incubation time, CY dose, and the time of tissue sampling after CY injection were investigated. The bioassay could detect cytotoxic metabolites in blood after doses as low as 10 mg kg-1 CY given i.p. The half life of these metabolites in blood after giving 400 mg kg-1 i.p. decreased over a 2 h period from 14 to 9 min. The method was then modified to define the pharmacokinetics of CY metabolites in two different types of tumour and in lung. The half life of the cytotoxic metabolites in the lung was longer than in blood, falling from 35 to 11 min over a 2 h period. In tumours, the half lives were longer again, i.e. approximately 61 min. The maximum metabolite levels achieved were similar in the two tumour types, although these differed markedly in their therapeutic response to CY. The bioassay for CY is a relatively simple and rapid procedure, and the extension of its application from body fluids to solid tissues makes it a useful tool in experimental pharmacokinetic studies

The Large Scale Roll-Out of Electric Vehicles: The Effect on the Electricity Sector and CO2 Emissions

The UK government has set the ambitious targets of 20 and 50% reduction in greenhouse gas emissions by 2020 and 2050 respectively. The transport sector accounts for 21% of total CO2 emissions in the UK and can, therefore, be important for achieving the emissions reduction targets. Within the transport sector, electric vehicles (EV) are considered as one of the important mitigation options. However the effect of EVs on emissions and the electricity sector is subject to debate. We use scenario analysis to investigate the emission reduction potential of EVs and their interaction with electricity sector. We show that managing the charging patterns could reduce adverse effects of EVs on the electricity sector while the number of EVs remains the factor affecting the mitigation potential. Our findings indicate that in the UK, by 2030, EVs could result in up to 32% emissions reduction compared to advanced internal combustion engines. We also found that the need for new electricity generation and distribution capacity to meet the conventional electricity demand and demand from EVs could be reduced by up to 12% from 70.6 to 61.8 GW if the EV’s electricity demand is managed

Operationalizing risk perception and preparedness behavior research for a multi-hazard context

Increasingly, citizens are being asked to take a more active role in disaster risk reduction (DRR), as decentralization of hazard governance has shifted greater responsibility for hazard preparedness actions onto individuals. Simultaneously, the taxonomy of hazards considered for DRR has expanded to include medical and social crises alongside natural hazards. Risk perception research emerged to support decision-makers with understanding how people characterize and evaluate different hazards to anticipate behavioral response and guide risk communication. Since its inception, the risk perception concept has been incorporated into many behavioral theories, which have been applied to examine preparedness for numerous hazard types. Behavioral theories have had moderate success in predicting or explaining preparedness behaviors; however, they are typically applied to a single hazard type and there is a gap in understanding which theories (if any) are suited for examining multiple hazard types simultaneously. This paper first reviews meta-analyses of behavioral theories to better understand performance. Universal lessons learnt are summarized for survey design. Second, theoretically based preparedness studies for floods, earthquakes, epidemics, and terrorism are reviewed to assess the conceptual requirements for a ‘multi-hazard’ preparedness approach. The development of an online preparedness self-assessment and learning platform is discussed

A Comparison of Treadmill and Overground Walking Effects on Step Cycle Asymmetry in Young and Older Individuals

Although lower limb strength becomes asymmetrical with age, past studies of aging effects on gait biomechanics have usually analyzed only one limb. This experiment measured how aging and treadmill surface influenced both dominant and nondominant step parameters in older (mean 74.0 y) and young participants (mean 21.9 y). Step-cycle parameters were obtained from 3-dimensional position/time data during preferred-speed walking for 40 trials along a 10 m walkway and for 10 minutes of treadmill walking. Walking speed (young 1.23 m/s, older 1.24 m/s) and step velocity for the two age groups were similar in overground walking but older adults showed significantly slower walking speed (young 1.26 m/s, older 1.05 m/s) and step velocity on the treadmill due to reduced step length and prolonged step time. Older adults had shorter step length than young adults and both groups reduced step length on the treadmill. Step velocity and length of older adults’ dominant limb was asymmetrically larger. Older adults increased the proportion of double support in step time when treadmill walking. This adaptation combined with reduced step velocity and length may preserve balance. The results suggest that bilateral analyses should be employed to accurately describe asymmetric features of gait especially for older adults

Effects of walking-induced fatigue on gait function and tripping risks in older adults

BACKGROUND: Fatigue and ageing contribute to impaired control of walking and are linked to falls. In this project, fatigue was induced by maximum speed walking to examine fatigue effects on lower limb trajectory control and associated tripping risk and overall gait functions of older adults. METHODS: Eleven young (18–35 years) and eleven older adults (>65 years) conducted 5-minute preferred speed treadmill walking prior to and following 6-minute maximum fast walking. Spatio-temporal gait parameters and minimum foot clearance (MFC) were obtained. Maximal muscle strength (hamstrings and quadriceps) was measured on an isokinetic dynamometer. Heart rate (HR) and rating of perceived exertion (RPE) assessed physiological effort and subjective fatigue. Physiological Cost Index computed walking efficiency. RESULTS: Fatigue due to fast walking increased step length, double support time and variability of step width. Only older adults reduced MFC due to fatigue. A trend of longer double support with greater MFC was found in the non-dominant limb. Lower walking efficiency was characterised as the ageing effect. Older adults did not increase HR during fast walking but higher RPE scores were observed. CONCLUSIONS: Older adults can increase tripping risk by 6 minutes of fast walking possibly by both impaired walking efficiency based on cardiac capacity and higher perceived fatigue due to elevated caution level. Regardless of age, increased step width variability due to fatigue was observed, a sign of impaired balance. Longer double support and greater MFC observed in the older adults’ non-dominant limb could be an asymmetrical gait adaptation for safety. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/1743-0003-11-155) contains supplementary material, which is available to authorized users

Fluctuations and Non-Hermiticity in the Stochastic Approach to Quantum Spins

We investigate the non-equilibrium dynamics of isolated quantum spin systems via an exact mapping to classical stochastic differential equations. We show that one can address significantly larger system sizes than recently obtained, including two-dimensional systems with up to 49 spins. We demonstrate that the results for physical observables are in excellent agreement with exact results and alternative numerical techniques where available. We further develop a hybrid stochastic approach involving matrix product states. In the presence of finite numerical sampling, we show that the non-Hermitian character of the stochastic representation leads to the growth of the norm of the time-evolving quantum state and to departures for physical observables at late times. We demonstrate approaches that correct for this and discuss the prospects for further development.Comment: 5 pages, 4 figures, Supplementary Materia

Trajectory-Resolved Weiss Fields for Quantum Spin Dynamics

We explore the dynamics of quantum spin systems in two and three dimensions using an exact mapping to classical stochastic processes. In recent work we explored the effectiveness of sampling around the mean field evolution as determined by a stochastically averaged Weiss field. Here, we show that this approach can be significantly extended by sampling around the instantaneous Weiss field associated with each stochastic trajectory taken separately. This trajectory-resolved approach incorporates sample to sample fluctuations and allows for longer simulation times. We demonstrate the utility of this approach for quenches in the two-dimensional and three-dimensional quantum Ising model. We show that the method is particularly advantageous in situations where the average Weiss-field vanishes, but the trajectory-resolved Weiss fields are non-zero. We discuss the connection to the gauge-P phase space approach, where the trajectory-resolved Weiss field can be interpreted as a gauge degree of freedom.Comment: 11 pages, 7 figure