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51.
The management of natural- and human-induced wildland fires is an intricate process that must balance two considerations: that of fire as a necessary natural disturbance and that of the risks that fire poses. Reconciling tradeoffs between these risks and benefits is contingent upon informed, directed, and two-way communication between wildland fire managers and stakeholders. In an effort to aid with the design of such a communication effort, this study used mental models research to determine the unique wildland fire information and decision-making needs of stakeholders living at the wildland-urban interface of a fire-prone area. While the analysis revealed many similarities in how stakeholders conceptualized the risks and benefits of wildland fire, many misconceptions and important gaps in understanding on the part of both expert and nonexpert respondents were identified.  相似文献   
52.
53.
One of the standard variable selection procedures in multiple linear regression is to use a penalisation technique in least‐squares (LS) analysis. In this setting, many different types of penalties have been introduced to achieve variable selection. It is well known that LS analysis is sensitive to outliers, and consequently outliers can present serious problems for the classical variable selection procedures. Since rank‐based procedures have desirable robustness properties compared to LS procedures, we propose a rank‐based adaptive lasso‐type penalised regression estimator and a corresponding variable selection procedure for linear regression models. The proposed estimator and variable selection procedure are robust against outliers in both response and predictor space. Furthermore, since rank regression can yield unstable estimators in the presence of multicollinearity, in order to provide inference that is robust against multicollinearity, we adjust the penalty term in the adaptive lasso function by incorporating the standard errors of the rank estimator. The theoretical properties of the proposed procedures are established and their performances are investigated by means of simulations. Finally, the estimator and variable selection procedure are applied to the Plasma Beta‐Carotene Level data set.  相似文献   
54.
We are trapped in two divergent worlds when it comes to global views on homosexuality. There is the liberal world epitomized by Spain and other nations, where homosexuality is increasingly accepted; gays and lesbians are claiming their human rights; and laws are changing to codify that transformation. The second is the extremely anti-gay world symbolized by Africa, the Middle East and parts of Asia, where attitudes are favorable to criminalization. This research explains the “African Gap” in attitudes toward homosexuality in a comparative analysis of six African nations and Argentina and Canada, South and North America's most liberal nations on gay rights. Using Pew's 2015 Spring Global Attitudes Survey data, we find that the major variables have essentially similar effects on opinion in any context. Africa's distinction is explained by its comparatively higher levels of factors such as religion, morality dogma, and low socioeconomic status that generally retard support for homosexuality, at the same time of lower levels of factors such as education, urbanization, and personal liberty that increase gay support. Africa's extreme anti-gay outlook is mutable. Two social forces will facilitate this softening: expansion of liberalizing agents such as education and urbanization, and repositioning away from “traditionalism” toward modernism emphasizing individualism, civil rights, and personal liberties.  相似文献   
55.
New mothers frequently seek information and community on social networking sites as they seek to establish their parenting practices. As social networking sites for mothers (SNSM) present an environmental influence on the family system, a mother’s experience with social comparison, belonging, and emotion on SNSM can bear significant influence over her satisfaction with her parenting. The present study utilized survey methods to explore mothers’ (n= 336) reported experiences of these variables. We use structural equation modeling to specify a model with good fit, which indicated that greater downward comparison directly related to greater parenting satisfaction, with belonging and negative emotion as mediating indirect relationships. Implications for family communication and mothers’ SNSM practices are discussed.  相似文献   
56.
The current study tests the association between a composite measure of unsafe sex and sharing syringes for drug use with six of the more common lifetime traumatic/stressful events in 421 community mental health clients with severe mental illness (SMI) while controlling for psychiatric symptoms and related problems. A small but significant proportion of respondents said they had injected drugs with a shared needle in their lifetime (30, 7.2%), and a much larger proportion of respondents had engaged in unprotected sex (165, 39.2%). Unprotected sex and needle sharing were significantly correlated (Spearman’s rho = .20, < .01). Frequency of lifetime traumatic events that occurred at least once was reported by one third to three quarters of clients depending on type of trauma. Regression analysis revealed that substance abuse and lifetime homelessness were significantly correlated with health risk behaviors. Practitioners need to be continuously vigilant to comorbid substance use and the housing needs of people with SMI. Limitations of the study include its cross-sectional design.  相似文献   
57.
The use of thimerosal preservative in childhood vaccines has been largely eliminated over the past decade in the United States because vaccines have been reformulated in single‐dose vials that do not require preservative. An exception is the inactivated influenza vaccines, which are formulated in both multidose vials requiring preservative and preservative‐free single‐dose vials. As part of an ongoing evaluation by USFDA of the safety of biologics throughout their lifecycle, the infant body burden of mercury following scheduled exposures to thimerosal preservative in inactivated influenza vaccines in the United States was estimated and compared to the infant body burden of mercury following daily exposures to dietary methylmercury at the reference dose established by the USEPA. Body burdens were estimated using kinetic parameters derived from experiments conducted in infant monkeys that were exposed episodically to thimerosal or MeHg at identical doses. We found that the body burden of mercury (AUC) in infants (including low birth weight) over the first 4.5 years of life following yearly exposures to thimerosal was two orders of magnitude lower than that estimated for exposures to the lowest regulatory threshold for MeHg over the same time period. In addition, peak body burdens of mercury following episodic exposures to thimerosal in this worst‐case analysis did not exceed the corresponding safe body burden of mercury from methylmercury at any time, even for low‐birth‐weight infants. Our pharmacokinetic analysis supports the acknowledged safety of thimerosal when used as a preservative at current levels in certain multidose infant vaccines in the United States.  相似文献   
58.
Schizotypal personality disorder (SPD) is considered to be a “schizophrenia spectrum disorder” as evidenced in part by its cross-listing in that chapter of the DSM-5. SPD is considered to be a condition with limited potential for positive change because one of its major features is the presence of a biologically based cognitive deficit. This assumption, however, is an example of the medical model’s creating a bias against psychosocial features that are always involved in character development. The social work profession’s bio-psycho-social perspectives focus more comprehensively on all features of the condition and promote a more optimistic view of clients’ change potentials. The purposes of this paper are to examine SPD from a social work perspective and to demonstrate, with a case example, how effective intervention can be organized and delivered.  相似文献   
59.
Lack of access to potable water and good sanitation is still one of the most challenging public health concerns of the twenty-first century despite steady progress over recent decades. Almost a billion people globally lack access to safe water; over two billion live without adequate sanitation facilities. The challenge is even more daunting for Sub-Saharan Africa where coverage levels for both potable water and sanitation remain critically low. The urgent need to address the issue calls for adequate understanding of the socio-economic dimensions. Using the 2008 Ghana Demographic and Health Survey, we investigated the socio-economic and demographic factors associated with access to potable water and improved sanitation facilities. Our generalized linear models reveal that income, education, household size, and region are significant predictors of improved water and sanitation access. Our discussion and conclusion sections highlight the implications of the study results for water policy formulation and implementation in Ghana, and broadly for other developing countries.  相似文献   
60.
Self-report purchase tasks are a novel approach examining the reinforcing value of addictive behaviour relative to increasing monetary costs required to access the addictive behaviour (i.e. demand). These measures reveal a positive relationship between the indices of demand and addiction problem severity and can elucidate factors associated with motivation for substance use. Gambling is an addictive behaviour that has not been examined using this paradigm. This study seeks to adapt and examine the purchase task for gambling behaviour. A gambling purchase task was devised that asked individuals how often per month they would gamble at various cover charges. Participants were 73 adults from the community with either gambling disorder (n = 28) or alcohol use disorder (n = 24) or were a healthy control (n = 21). Both the alcohol and gambling purchase tasks were administered. Results demonstrate discriminant validity of the gambling purchase task, as individuals with gambling disorder have significantly greater demand for accessing gambling than other groups. The alcohol purchase task also evidenced discriminant validity in that individuals with alcohol use disorder have significantly greater demand for alcohol than other groups. These findings support the use of the gambling purchase task to assess the demand for gambling.  相似文献   
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