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41.
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, p < .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
42.
Robert J. Mitkus David B. King Mark O. Walderhaug Richard A. Forshee 《Risk analysis》2014,34(4):735-750
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
43.
Ellis Adjei Adams Godfred O. Boateng Jonathan A. Amoyaw 《Social indicators research》2016,126(2):673-687
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
44.
Caroline K. Pemberton Roben Anneliese J. Bass Ginger A. Moore Laura Murray‐Kolb Patricia Z. Tan Rick O. Gilmore Kristin A. Buss Pamela M. Cole Laureen O. Teti 《Infancy》2012,17(5):558-577
Infants’ emerging ability to move independently by crawling is associated with changes in multiple domains, including an increase in expressions of anger in situations that block infants’ goals, but it is unknown whether increased anger is specifically because of experience with being able to move autonomously or simply related to age. To examine the influence of locomotion on developmental change in anger, infants’ (N = 20) anger expressions during an arm restraint procedure were observed longitudinally at a precrawling baseline assessment and 2 and 6 weeks after the onset of crawling. Infant age at each crawling stage was unrelated to the frequency of anger expressed in response to arm restraint. At 6 weeks postcrawling onset, infants whose mothers rated them as temperamentally higher in distress to limitations, compared with those rated lower, showed a greater increase in the frequency of anger expressed during the arm restraint relative to earlier assessments and took longer to reduce the frequency of anger expressed when no longer restrained. Findings suggest that experience with autonomous crawling has an effect on anger expression, independent of age, and that a temperamental tendency to become distressed by limitations may exacerbate the effect of crawling on anger expression. 相似文献
45.
ABSTRACTWe consider the case of production units arranged into a number of groups. All units within a group choose output–input combinations from the same production possibilities set that is represented by a stochastic frontier model. The metafrontier is the envelope of the group-specific frontiers. We are interested in the metafrontier distance, which is the amount by which the group-specific frontier lies below the metafrontier.Previous work has measured the metafrontier distance using the deterministic portion of the frontier. In a stochastic frontier model, this is not appropriate. We show how to evaluate the metafrontier distance, and we demonstrate the empirical relevance of this issue. 相似文献
46.
47.
Babak Shahbaba Shiwei Lan Wesley O. Johnson Radford M. Neal 《Statistics and Computing》2014,24(3):339-349
We show how the Hamiltonian Monte Carlo algorithm can sometimes be speeded up by “splitting” the Hamiltonian in a way that allows much of the movement around the state space to be done at low computational cost. One context where this is possible is when the log density of the distribution of interest (the potential energy function) can be written as the log of a Gaussian density, which is a quadratic function, plus a slowly-varying function. Hamiltonian dynamics for quadratic energy functions can be analytically solved. With the splitting technique, only the slowly-varying part of the energy needs to be handled numerically, and this can be done with a larger stepsize (and hence fewer steps) than would be necessary with a direct simulation of the dynamics. Another context where splitting helps is when the most important terms of the potential energy function and its gradient can be evaluated quickly, with only a slowly-varying part requiring costly computations. With splitting, the quick portion can be handled with a small stepsize, while the costly portion uses a larger stepsize. We show that both of these splitting approaches can reduce the computational cost of sampling from the posterior distribution for a logistic regression model, using either a Gaussian approximation centered on the posterior mode, or a Hamiltonian split into a term that depends on only a small number of critical cases, and another term that involves the larger number of cases whose influence on the posterior distribution is small. 相似文献
48.
Leanne ten Brinke Stephen Porter Natasha Korva Katherine Fowler Scott O. Lilienfeld Christopher J. Patrick 《Journal of Nonverbal Behavior》2017,41(3):269-287
Psychopathic individuals are characterized as “intra-species predators”—callous, impulsive, aggressive, and proficient at interpersonal manipulation. For example, despite their high risk for re-offending, psychopathic offenders often receive early release on parole. While reputed to be social chameleons, research suggests that even naive observers can accurately infer high levels of psychopathic traits in others with very brief exposures to behavior, but accuracy degrades with extended observation. We utilized a lens model approach to examine the communication styles (emotional facial expressions, body language, and verbal content) of offenders varying in levels of psychopathic traits using “thin slice” video clips of psychological assessment interviews and to reveal which cues observers use to inform their evaluations of psychopathy. Psychopathic traits were associated with more (a) Duchenne smiles, (b) negative (angry) emotional language, and (c) hand gestures (illustrators). Further, psychopathy was associated with a marked behavioral incongruence; when individuals scoring high in psychopathic traits engaged in Duchenne smiles they were also more likely to use angry language. Naïve observers relied on each of these valid behavioral signals to quickly and accurately detect psychopathic traits. These findings provide insight into psychopathic communication styles, opportunities for improving the detection of psychopathic personality traits, and may provide an avenue for understanding successful psychopathic manipulation. 相似文献
49.
Nnamdi Ifeanyi Maduekwe Olufunmilayo O. Banjo Mike O. Sangodapo 《Social indicators research》2017,134(2):651-674
Civil Registration and Vital Statistics (CRVS) Systems are playing increasing roles in national and global data infrastructure, facilitating the achievement of key developmental goals. The performance of CRVS systems in many developing countries including Nigeria is sub optimal and information on their structure and operations scanty. This paper characterizes the statutory, institutional, and operational elements and social contexts of the Nigerian CRVS System. It includes a context analysis of the system and a review of improvement strategies and interventions. The paper shows that the Nigerian CRVS System is built on viable statutory and institutional platforms—the constitutional enshrinement of: universal, compulsory and continuous civil registration and, a central registration institution—the National Population Commission (NPC). NPC has registration hierarchy and infrastructure deployed at every level of political administration and mechanisms for efficient coordination of registration and production of vital statistics on live-births, deaths and stillbirths amongst other vital events. The major weaknesses of the system include inadequate financing and deployment of registration facilities, conflicting statutes and institutional arrangements for the registration of key events like death and stillbirths. Other weaknesses include intra-organizational conflicts in resource allocation and weak ICT infrastructure within the NPC. These are compounded by overarching contextual issues namely registration unfriendly sociocultural norms, weak national data infrastructure, systemic corruption, poverty and undeveloped civic culture. Domestic initiatives and interventions to improve the system have focused on birth registration, while multilateral interventions have only made a modest impact on the system. Thus, holistic in-country improvement initiatives supported with robust interventions are imperative to overcome weaknesses in the Nigerian CRVS system. However fundamental improvements in CRVS systems in developing countries like Nigeria may likely only follow sustainable solutions to overarching contextual issues especially poor infrastructure, weak institutions, poverty and systemic corruption. 相似文献
50.