4,524 research outputs found

    The minimum energy expenditure shortest path method

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    This article discusses the addition of an energy parameter to the shortest path execution process; namely, the energy expenditure by a character during execution of the path. Given a simple environment in which a character has the ability to perform actions related to locomotion, such as walking and stair stepping, current techniques execute the shortest path based on the length of the extracted root trajectory. However, actual humans acting in constrained environments do not plan only according to shortest path criterion, they conceptually measure the path that minimizes the amount of energy expenditure. On this basis, it seems that virtual characters should also execute their paths according to the minimization of actual energy expenditure as well. In this article, a simple method that uses a formula for computing vanadium dioxide (VO2VO_2) levels, which is a proxy for the energy expenditure by humans during various activities, is presented. The presented solution could be beneficial in any situation requiring a sophisticated perspective of the path-execution process. Moreover, it can be implemented in almost every path-planning method that has the ability to measure stepping actions or other actions of a virtual character

    Co-existing violence and self-harm: dual harm in an early-stage male prison population

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    Purpose: This study examined the characteristics of men in prison who have a history of both self-harm and violence (known as dual harm) and the extent to which demographic and criminogenic factors, in-prison incidents and self-harm method could differentiate men who dual harm. Methods: Official prison sample data were examined for the period April 2010 to November 2017 (n = 965). Regression analysis of all custodial incidents, demographic and offending information, and imprisonment experience, was undertaken. Results: Self harm was associated with violence in prison, representing a 3.5-fold risk of violence compared with men who did not self-harm, after controlling for time in prison, age and index offence. 60% of men who harmed themselves also engaged in custodial violence, while 32% who were violent also had a self-harm event. After controlling for age at first incident, 11% of the sample had custodial history of dual harm and they accounted for 56% of all recorded custodial incidents. They had a high probability of property damage and fire-setting in prison and spent 40% longer in custody). Men who dual harmed used a greater variety of self-harm methods, with increased use of lethal methods. Conclusion: Dual harm is prevalent, particularly amongst those who harm themselves in prison. Men who dual harm contribute excessively to the overall incident burden in prison and demonstrate behavioural variability and risk regarding both violence and self-harm. The findings challenge the usual distinctive management responses or that self-harm or violence are solely the responsibility of health or justice; with greater integration required

    Persistence of balsam fir and black spruce populations in the mixedwood and coniferous bioclimatic domain of eastern North America

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    The boreal ecocline (ca 49Ā°N) between the southern mixedwood (dominated by balsam fir) and the northern coniferous bioclimatic domain (dominated by black spruce) may be explained by a northward decrease of balsam fir regeneration, explaining the gradual shift to black spruce dominance. 7,010 sample plots, with absence of major disturbances, were provided by the Quebec Ministry of Forest, Fauna, and Parks. The regeneration (sapling abundance) of balsam fir and black spruce were compared within and between the two bioclimatic domains, accounting for parental trees, main soil type (clay and till) and climate conditions, reflected by summer growing degree-days above 5Ā°C (GDD_5), total summer precipitation (Mayā€“August; PP_MA). Parental trees and soil type determined balsam fir and black spruce regeneration. Balsam fir and black spruce, respectively, showed higher regeneration in the mixedwood and the coniferous bioclimatic domains. Overall, higher regeneration was obtained on till for balsam fir, and on clay soils for black spruce. GDD_5 and PP_MA were beneficial for balsam fir regeneration on clay and till soils, respectively, while they were detrimental for black spruce regeneration. At a population level, balsam fir required at least 28% of parental tree basal area in the mixedwood, and 38% in the coniferous bioclimatic domains to maintain a regeneration at least equal to the mean regeneration of the whole study area. However, black spruce required 82% and 79% of parental trees basal area in the mixedwood and the coniferous domains, respectively. The northern limit of the mixedwood bioclimatic domain was attributed to a gradual decrease toward the north of balsam fir regeneration most likely due to cooler temperatures, shorter growing seasons, and decrease of the parental trees further north of this northern limit. However, balsam fir still persists above this northern limit, owing to a patchy occurrence of small parental trees populations, and good establishment substrates

    Gender, age and the MBA: An analysis of extrinsic and intrinsic career benefits

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    Against the background of an earlier UK study, this paper presents the findings of a Canadian based survey of career benefits from the MBA. Results indicate firstly that gender and age interact to influence perceptions of career outcomes (young men gain most in terms of extrinsic benefits of career change and pay), and secondly that both men and women gain intrinsic benefits from the MBA. However, intrinsic benefits vary by gender: men in the study were more likely to say they gained confidence from having a fuller skill set while women were more likely to say they gained confidence from feelings of self worth; men emphasised how they had learned to give up control while women argued that they had gained a ā€˜voiceā€™ in the organization. The role of the MBA in career self- management and the acquisition of key skills are examined as well as the implications for the design of programmes in meeting the varied need of men and women in different age groups

    A critical review of the formation of mono- and dicarboxylated metabolic intermediates of alkylphenol polyethoxylates during wastewater treatment and their environmental significance

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    This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2010 Taylor & Francis.Alkylphenoxyacetic acids, the metabolic biodegradation products of alkylphenol ethoxylates, are commonly found in wastewaters and sewage effluents. These persistent hydrophilic derivatives possess intrinsic estrogenic activity, which can mimic natural hormones. Their concentrations increase through the sewage treatment works as a result of biodegradation and biotransformation, and when discharged can disrupt endocrine function in fish. These acidic metabolites represent the dominant alkylphenolic compounds found in wastewater effluent and their presence is cause for concern as, potentially, through further biotransformation and biodegradation, they can act as sources of nonylphenol, which is toxic and estrogenic. The authors aim to assess the mechanisms of formation as well as elimination of alkylphenoxyacetic acids within conventional sewage treatment works with the emphasis on the activated sludge process. In addition, they evaluate the various factors influencing their degradation and formation in laboratory scale and full-scale systems. The environmental implications of these compounds are considered, as is the need for tertiary treatment processes for their removal

    Sexual selection drives weak positive selection in protamine genes and high promoter divergence, enhancing sperm competitiveness

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    Phenotypic adaptations may be the result of changes in gene structure or gene regulation, but little is known about the evolution of gene expression. In addition, it is unclear whether the same selective forces may operate at both levels simultaneously. Reproductive proteins evolve rapidly, but the underlying selective forces promoting such rapid changes are still a matter of debate. In particular, the role of sexual selection in driving positive selection among reproductive proteins remains controversial, whereas its potential influence on changes in promoter regions has not been explored. Protamines are responsible for maintaining DNA in a compacted form in chromosomes in sperm and the available evidence suggests that they evolve rapidly. Because protamines condense DNA within the sperm nucleus, they influence sperm head shape. Here, we examine the influence of sperm competition upon protamine 1 and protamine 2 genes and their promoters, by comparing closely related species of Mus that differ in relative testes size, a reliable indicator of levels of sperm competition. We find evidence of positive selection in the protamine 2 gene in the species with the highest inferred levels of sperm competition. In addition, sperm competition levels across all species are strongly associated with high divergence in protamine 2 promoters that, in turn, are associated with sperm swimming speed. We suggest that changes in protamine 2 promoters are likely to enhance sperm swimming speed by making sperm heads more hydrodynamic. Such phenotypic changes are adaptive because sperm swimming speed may be a major determinant of fertilization success under sperm competition. Thus, when species have diverged recently, few changes in gene-coding sequences are found, while high divergence in promoters seems to be associated with the intensity of sexual selection

    On epidemic modeling in real time: An application to the 2009 Novel A (H1N1) influenza outbreak in Canada

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    <p>Abstract</p> <p>Background</p> <p>Management of emerging infectious diseases such as the 2009 influenza pandemic A (H1N1) poses great challenges for real-time mathematical modeling of disease transmission due to limited information on disease natural history and epidemiology, stochastic variation in the course of epidemics, and changing case definitions and surveillance practices.</p> <p>Findings</p> <p>The Richards model and its variants are used to fit the cumulative epidemic curve for laboratory-confirmed pandemic H1N1 (pH1N1) infections in Canada, made available by the Public Health Agency of Canada (PHAC). The model is used to obtain estimates for turning points in the initial outbreak, the basic reproductive number (R<sub>0</sub>), and for expected final outbreak size in the absence of interventions. Confirmed case data were used to construct a best-fit 2-phase model with three turning points. R<sub>0 </sub>was estimated to be 1.30 (95% CI 1.12-1.47) for the first phase (April 1 to May 4) and 1.35 (95% CI 1.16-1.54) for the second phase (May 4 to June 19). Hospitalization data were also used to fit a 1-phase model with R<sub>0 </sub>= 1.35 (1.20-1.49) and a single turning point of June 11.</p> <p>Conclusions</p> <p>Application of the Richards model to Canadian pH1N1 data shows that detection of turning points is affected by the quality of data available at the time of data usage. Using a Richards model, robust estimates of R<sub>0 </sub>were obtained approximately one month after the initial outbreak in the case of 2009 A (H1N1) in Canada.</p

    A Comparison of Women of Color and Non-Hispanic White Women on Factors Related to Leaving a Violent Relationship

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    This study compares women of color and non-Hispanic White women regarding the influence of socioeconomic status, family investment, and psychological abuse on leaving a violent relationship. It was found that most women who left stayed away for less than a month. Women of color and non-Hispanic White women did not differ in their length or rate of leaving, although women of color left more frequently when they did leave. Factors associated with leaving for both groups were threat with a weapon, psychological abuse, being single, and having fewer adults in the household. Women of color with higher socioeconomic status were less likely to leave, which was not the case for non-Hispanic White women. Non-Hispanic White women were more likely to leave if they had lived with their partners less than 5 years and had children at home.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90886/1/Lacey-Saunders-Zhang 2011-Women of color vs white women - factors in leaving violent relationahip JIV .pd
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