2,609 research outputs found
The minimum energy expenditure shortest path method
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 () 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
A Comparison of Women of Color and Non-Hispanic White Women on Factors Related to Leaving a Violent Relationship
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
A critical review of the formation of mono- and dicarboxylated metabolic intermediates of alkylphenol polyethoxylates during wastewater treatment and their environmental significance
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
Gender, age and the MBA: An analysis of extrinsic and intrinsic career benefits
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 βvoiceβ 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
Developments in determining the gravitational potential using toroidal functions
have shown how the integration/summation expression for the Green's function in cylindrical coordinates can be written as an azimuthal Fourier series expansion, with toroidal functions as expansion coefficients. In this paper, we show how this compact representation can be extended to other rotationally invariant coordinate systems which are known to admit separable solutions for Laplace's equation
Spatiotemporal heterogeneity decouples infection parameters of amphibian chytridiomycosis
This is the author accepted manscript. The final version is available from Wiley via the DOI in this record1. Emerging infectious diseases are responsible for declines in wildlife populations around the globe. Mass mortality events associated with emerging infectious diseases are often associated with high number of infected individuals (prevalence)
and high pathogen loads within individuals (intensity). At the landscape scale
spatial and temporal variation in environmental conditions can alter the relationship
between these infection parameters and blur the overall picture of disease dynamics.
2. Quantitative estimates of how infection parameters covary with environmental
heterogeneity at the landscape scale are scarce. Predicting rates of pathogen
transmission and identifying wild populations at risk of disease epidemics requires
that we elucidate the factors that shape, and potentially decouple, the link between pathogen prevalence and intensity of infection over complex ecological landscapes.
3. Using a network of 41 populations of the amphibian host Rana pipiens in Ontario,
Canada, we present the spatial and temporal heterogeneity in pathogen prevalence
and intensity of infection of the chytrid fungus Batrachochytrium dendrobatidis
(Bd), across a 3-year period. We then quantify how covariation between both
infection parameters measured during late summer, are modified by previously
experienced spatiotemporal environmental heterogeneity across 14 repeat sampled
populations.
4. Late summer Bd infection parameters are governed, at least in part, by different environmental factors operating during separate host life history events. Our results provide evidence for a relationship between Bd prevalence and thermal regimes
prior to host breeding at the site level, and a relationship between intensity of
infection and aquatic conditions (precipitation, hydroshed size and river density) throughout host breeding period at the site level. This demonstrates that
microclimatic variation within temporal windows, can drive divergent patterns of pathogen dynamics within and across years, by effecting changes in host behaviour which interfere with the pathogenβs ability to infect and re-infect hosts.
5. A clearer understanding of the role that spatiotemporal heterogeneity has upon
infection parameters will provide valuable insights into host-pathogen
epidemiology, as well as more fundamental aspects of the ecology and evolution of interspecific interactions.Natural Environment Research Council (NERC)Ontario Trillium FoundationOntario Ministry of Natural Resources and ForestryParks Canada AgencyNature Conservancy of CanadaSt. Clair Region Conservation Authorit
Rapid evolution of virulence and drug resistance in the emerging zoonotic pathogen Streptococcus suis
Background: Streptococcus suis is a zoonotic pathogen that infects pigs and can occasionally cause serious infections in
humans. S. suis infections occur sporadically in human Europe and North America, but a recent major outbreak has been
described in China with high levels of mortality. The mechanisms of S. suis pathogenesis in humans and pigs are poorly
understood.
Methodology/Principal Findings: The sequencing of whole genomes of S. suis isolates provides opportunities to
investigate the genetic basis of infection. Here we describe whole genome sequences of three S. suis strains from the same
lineage: one from European pigs, and two from human cases from China and Vietnam. Comparative genomic analysis was
used to investigate the variability of these strains. S. suis is phylogenetically distinct from other Streptococcus species for
which genome sequences are currently available. Accordingly, ,40% of the ,2 Mb genome is unique in comparison to
other Streptococcus species. Finer genomic comparisons within the species showed a high level of sequence conservation;
virtually all of the genome is common to the S. suis strains. The only exceptions are three ,90 kb regions, present in the two
isolates from humans, composed of integrative conjugative elements and transposons. Carried in these regions are coding
sequences associated with drug resistance. In addition, small-scale sequence variation has generated pseudogenes in
putative virulence and colonization factors.
Conclusions/Significance: The genomic inventories of genetically related S. suis strains, isolated from distinct hosts and
diseases, exhibit high levels of conservation. However, the genomes provide evidence that horizontal gene transfer has
contributed to the evolution of drug resistance
Comparing the health of low income and less well educated groups in the United States and Canada
<p>Abstract</p> <p>Background</p> <p>A limited number of health status and health-related quality of life (HRQL) measures have been used for inter-country comparisons of population health. We compared the health of Canadians and Americans using a preference-based measure.</p> <p>Methods</p> <p>The Joint Canada/United States Survey of Health (JCUSH) 2002β03 conducted a comprehensive cross-sectional telephone survey on the health of community-dwelling residents in Canada and the US (n = 8688). A preference-based measure, the Health Utilities Index Mark 3 (HUI3), was included in the JCUSH. Health status was analyzed for the entire population and white population only in both countries. Mean HUI3 overall scores were compared for both countries. A linear regression determinants of health model was estimated to account for differences in health between Canada and the US. Estimation with bootstraps was used to derive variance estimates that account for the survey's complex sampling design of clustering and stratification.</p> <p>Results</p> <p>Income is associated with health in both countries. In the lowest income quintile, Canadians are healthier than Americans. At lower levels of education, again Canadians are healthier than Americans. Differences in health among subjects in the JCUSH are explained by age, gender, education, income, marital status, and country of residence.</p> <p>Conclusion</p> <p>On average, population health in Canada and the US is similar. However, health disparities between Canadians and Americans exist at lower levels of education and income with Americans worse off. The results highlight the usefulness of continuous preference-based measures of population health such as the HUI3.</p
Effects of place attachment on home return travel: a spatial perspective
Recent studies on place-mobility relationships suggest an increasing possibility that people can have multiple place attachments at varied spatial scales. Yet our understanding of how place attachment in different spatial scales affects mobility remains limited. This study investigates home return visits by Chinese diaspora tourists from North America who have made multiple trips to China. A total of 27 in-depth interviews with repeat home return travellers was conducted. Four different types of return movements were identified: local; dispersed; local & dispersed; and second-migration locale focused. A relationship was found between the participantsβ sense of place, place identity and home return travel. The findings suggest that home return travel is more complex than previously thought. More focused sense of place and strong personal connection to ancestral homes may lead to more localized return, while a more generic sense of place (i.e. to βChinaβ) and collective personal identity would result in a more dispersed travel pattern. Family migration history and strong attachment to familyβs first migration destination also leads to focused return to the place. The study highlights the fact that place and place attachment are deeply personal and can evolve over time and space
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