Perceptions of Ecological Risk Associated with Mountain Pine Beetle (Dendroctonus ponderosae) Infestations in Banff and Kootenay National Parks of Canada

Western Canada is experiencing an unprecedented outbreak of the mountain pine beetle (MPB). The MPB has the potential to impact some of Canada's national parks by affecting park ecosystems and the visitor experience. Controls have been initiated in some parks to lessen the impacts and to prevent the beetle from spreading beyond park boundaries. We examine the perception of ecological risk associated with MPB in two of Canada's national parks, the factors affecting perceptions of risk, and the influence of risk judgments on support for controlling MPB outbreaks in national parks. Data were collected using two studies of park visitors: a mail survey in 2003 and an onsite survey in 2005. The MPB was rated as posing a greater risk to the health and productivity of park ecosystems than anthropogenic hazards and other natural disturbance agents. Visitors who were familiar with MPB rated the ecological and visitor experience impacts as negative, unacceptable, and eliciting negative emotion. Knowledge and residency were the most consistent predictors of risk judgments. Of knowledge, risk, and demographic variables, only sex and risk to ecosystem domains influenced support for controlling the MPB in national parks. Implications for managing MPB in national parks, visitor education, and ecological integrity are discussed.     

‘CRASH’ – TOWARDS A CRITICAL PEDAGOGY OF WHITENESS?

Critical whiteness studies has produced significant analysis of the terrors of white supremacist power. However, in relation to cultural-media studies pedagogy, impassioned calls for the denouncement of whiteness raise troublesome concerns and limits for productively addressing students' racialized identities. I maintain that renouncing whiteness in anti-racist teaching does not adequately connect with commonsense and affective experiences of ‘race’ in everyday life for many students. Through a ‘materialist’ analysis of the film Crash (2005), this article opens up the question of the im/possibility of engaging whiteness from an anti-racist stance that neither condemns nor buttresses white identity. Crash, considered from a reading practice that does not simply dwell on textual meaning and interpretation, offers an opportunity to pedagogically engage with the ambivalent representations of ‘race’ which pervade contemporary culture.     

Fostering families' and children's rights to family connections

Recent federal legislation strengthens children's and families' rights to family-centered practice by increasing the responsibility of child welfare agencies to identify and engage extended family members in providing care and support to children placed out of the home. Preliminary results from an experimental study of a federally funded family finding project found greater involvement of family, kin, and informal supports and a higher likelihood of reunification or relative placement compared with standard child welfare services.     

Application of PBIB designs in CDC Method IV

In this paper we propose the use of some partially balanced incomplete block designs for blocking in complete diallel cross Method IV (Griffing, 1956) to deal with the situation when it is not desirable for all crosses to be accommodated in the block of a traditional randomized block design. A method is also proposed to analyse the MatingEnvironment designs for estimating the general combining ability effect of lines.     

THE EFFECTS OF CORRELATION AMONG OBSERVATIONS ON THE ACCURACY OF APPROXIMATING THE DISTRIBUTION OF SAMPLE MEAN BY ITS ASYMPTOTIC DISTRIBUTION1

In this paper, we investigate the effects of correlation among observations on the accuracy of approximating the distribution of sample mean by its asymptotic distribution. The accuracy is investigated by the Berry-Esseen bound (BEB), which gives an upper bound on the error of approximation of the distribution function of the sample mean from its asymptotic distribution for independent observations. For a given sample size (n₀) the BEB is obtained when the observations are independent. Let this be BEB. We then find the sample size (n_*) required to have BEB below BEB₀, when the observations are dependent. Comparison of n_* with n₀ reveals the effects of correlation among observations on the accuracy of the asymptotic distribution as an approximation. It is shown that the effects of correlation among observations are not appreciable if the correlation is moderate to small but it can be severe for extreme correlations.     

A Predictive Model for Survival of Escherichia coli O157:H7 and Generic E. coli in Soil Amended with Untreated Animal Manure

This study aimed at developing a predictive model that captures the influences of a variety of agricultural and environmental variables and is able to predict the concentrations of enteric bacteria in soil amended with untreated Biological Soil Amendments of Animal Origin (BSAAO) under dynamic conditions. We developed and validated a Random Forest model using data from a longitudinal field study conducted in mid-Atlantic United States investigating the survival of Escherichia coli O157:H7 and generic E. coli in soils amended with untreated dairy manure, horse manure, or poultry litter. Amendment type, days of rain since the previous sampling day, and soil moisture content were identified as the most influential agricultural and environmental variables impacting concentrations of viable E. coli O157:H7 and generic E. coli recovered from amended soils. Our model results also indicated that E. coli O157:H7 and generic E. coli declined at similar rates in amended soils under dynamic field conditions.The Random Forest model accurately predicted changes in viable E. coli concentrations over time under different agricultural and environmental conditions. Our model also accurately characterized the variability of E. coli concentration in amended soil over time by providing upper and lower prediction bound estimates. Cross-validation results indicated that our model can be potentially generalized to other geographic regions and incorporated into a risk assessment for evaluating the risks associated with application of untreated BSAAO. Our model can be validated for other regions and predictive performance also can be enhanced when data sets from additional geographic regions become available.     

On Variance Upper Bounds for Unimodal Distributions

We obtain upper bounds on the variance of discrete unimodal distributions. The alternative proofs of the corresponding bounds for the continuous unimodal distributions are also given.     

Rural‐Urban Differences in Environmental Concern in Canada

Abstract Distinctions between rural and urban populations are well documented in environmental sociology literature. Rural and urban places may exert different influences on participation in environmentally supportive behavior (ESB) as well as on other forms of environmental concern (EC). The influence of these distinct geographies may be due to present circumstances or because of childhood socialization in these places. Using data from a national survey in Canada (n=51 664), we use cognitive (basic values, environmental worldview, and environmental attitude) and behavioral indicators (public and private sphere) of EC to explore differences among rural and urban populations and we include analyses accounting for place of socialization. We extend the conventional private sphere category of ESB by including stewardship behaviors. Results showed few differences between rural and urban residents on indicators of EC. Rural residents, however, scored higher on altruistic values, placed a higher priority on the environment, and reported higher participation in recycling and stewardship behaviors. Analysis that included place of socialization showed differences on environmental worldview, basic values, and some ESB. In terms of ESB, we conclude that residence and place of socialization may be less of a factor than opportunity and highlight the importance of providing services and facilities. We recommend future research on residence and ESB include a variety of behaviors that reflect opportunities for both rural and urban residents.     

外包趋势不可逆 奥巴马的政治限制影响甚微

自从奥巴马接任美国总统以来，严重依赖美国的印度外包产业一度感到胆战心惊：首先，奥巴马大幅减少了允许外国工人在美国本土就业的H-1b工作签证；接着奥巴马又在2月24日的国会讲话中宣布“终止美国公司外包业务的减税优惠”。