Modeling of Salmonella Contamination in the Pig Slaughterhouse.

In this article we present a model for Salmonella contamination of pig carcasses in the slaughterhouse. This model forms part of a larger QMRA (quantitative microbial risk assessment) on Salmonella in slaughter and breeder pigs, which uses a generic model framework that can be parameterized for European member states, to describe the entire chain from farm-to-consumption and the resultant human illness. We focus on model construction, giving mathematical formulae to describe Salmonella concentrations on individual pigs and slaughter equipment at different stages of the slaughter process. Variability among individual pigs and over slaughterhouses is incorporated using statistical distributions, and simulated by Monte Carlo iteration. We present the results over the various slaughter stages and show that such a framework is especially suitable to investigate the effect of various interventions. In this article we present the results of the slaughterhouse module for two case study member states. The model outcome represents an increase in average prevalence of Salmonella contamination and Salmonella numbers at dehairing and a decrease of Salmonella numbers at scalding. These results show good agreement when compared to several other QMRAs and microbiological studies.

Detecting new and emerging diseases on livestock farms using an early detection system.

The monitoring and surveillance of animal diseases is becoming increasingly important to policy-makers in Great Britain particularly given recent incursions of avian influenza and the emergence of bovine spongiform encephalopathy. To meet this surveillance objective, data from British livestock is collected and analysed retrospectively on an ongoing basis. However, these data can also be analysed prospectively within an early detection system which raises alerts to significant increases in disease reporting soon after they occur in the field. The feasibility of such an approach has been examined previously for Salmonella. This paper applied the approach to a further subset of surveillance data to alert those monitoring disease to increases in potentially new and emerging diseases. Thus far, the analysis, conducted on a quarterly basis, has proved a useful additional tool in enhanced surveillance by raising alerts to significant increases in several syndromes in both sheep and cattle.

The influence of neighborhood disadvantage, collective socialization, and parenting on African American children's affiliation with deviant peers.

This study focused on hypotheses about the contributions of neighborhood disadvantage, collective socialization, and parenting to African American children's affiliation with deviant peers. A total of 867 families living in Georgia and Iowa, each with a 10- to 12-year-old child, participated. Unique contributions to deviant peer affiliation were examined using a hierarchical linear model. Community disadvantage derived from census data had a significant positive effect on deviant peer affiliations. Nurturant/involved parenting and collective socialization processes were inversely associated, and harsh/inconsistent parenting was positively associated, with deviant peer affiliations. The effects of nurturant/involved parenting and collective socialization were most pronounced for children residing in the most disadvantaged neighborhoods.

Sisters, brothers, and delinquency: evaluating social influence during early and middle adolescence.

Although a number of studies have shown that brothers are highly correlated for delinquent behavior, much less research has been conducted on sisters. We propose that sisters, like brothers, show notable similarity for delinquent behavior, and also promote each other's delinquency through direct interaction. We examined these issues in 164 brother and sister pairs studied over a 4-year period (from early to middle adolescence) in a study of intact families in the rural Midwest. Sibling similarity for self-reports of delinquent behavior were highly correlated for both brothers and sisters. Conditional effects of high levels of hostile-coercive sibling relationships and older sibling delinquency predicted younger sibling delinquency in both brother and sister pairs. For brothers, conditional effects were also detected for high levels of warmth-support, in contrast to sisters. The conditional effects of older sibling delinquency and relationship quality were shown to predict change in younger sibling delinquency through adolescence. The results add to a growing literature on sibling effects as well as theoretical models that emphasize the role of social interaction between siblings as a risk factor for the development of delinquent activity in adolescence.

Nasal tip bossae in rhinoplasty. Etiology, predisposing factors, and management techniques.

OBJECTIVES: To identify preoperative risk factors and surgical techniques that influence the risk of developing postoperative nasal tip bossae in rhinoplasty. A secondary objective was to review the characteristics, management techniques, and outcomes of those study patients with postoperative bossae. DESIGN: Univariate and multivariate analysis carried out in a case series. SETTING: Private facial plastic surgery practice. PATIENTS: All patients who underwent aesthetic nasal surgery that included surgical modification of the nasal tip, and in whom documentation was complete and photographic follow-up was available, were considered eligible. The study group consisted of 875 patients of whom 37 (4.2%) developed bossae postoperatively. MAIN OUTCOME MEASURES: Potential risk factors for postoperative bossae included age, sex, previous nasal surgery, preoperative tip asymmetry, preoperative lobular bifidity, preoperative bossae, skin thickness, surgical tip technique, use of columellar struts, columellar battens, lobular crushed cartilage grafts, and tip shield grafts. RESULTS: In the univariate analysis, females, patients undergoing primary rhinoplasty, younger age groups (12- to 22-year-olds), thin skin, and widened interdomal distance (bifidity) were all noted to have moderate or strong associations with nasal tip bossae. In the multivariate analysis, the younger age group, thin skin, and bifidity were statistically significant and independently associated with nasal tip bossae, independent of the type of tip surgery. In addition, clinically relevant associations were noted in females and patients undergoing primary rhinoplasty. Recognition of risk factors, preventive measures, and treatment methods is recommended.

Predicting risk for pregnancy by late adolescence: a social contextual perspective.

To evaluate a model of social contextual influences on risk for adolescent pregnancy, 368 target adolescents (52% female, 48% male) and their mothers, fathers, and closest age siblings were assessed 6 times over a 7-year period beginning when the target adolescents were in 7th grade. Two pathways were found to increase risk for involvement in a pregnancy by late adolescence. Middle adolescent risk-taking behavior mediated the influence of early adolescent parental warmth-involvement and deviant-peer affiliations on involvement in a pregnancy by 12th grade. Also, early adolescent academic competence mediated the relationship between parental warmth-involvement and involvement in a pregnancy by 12th grade. Theoretical and practical implications of the results are discussed.

Parents and peer group as mediators of the effect of community structure on adolescent problem behavior.

Used a sample of 207 single-parent families residing in 104 small, Midwestern communities to test hypotheses regarding the link between community context and adolescent conduct problems and psychological distress. For boys, community disadvantage had a direct affect on psychological distress, while it indirectly boosted the probability of conduct problems by disrupting parenting and increasing affiliation with deviant peers. Community disadvantage was unrelated to the deviant behavior or emotional well-being of girls. Proportion of single-parent households in the community had a direct effect on girls' conduct problems. It also contributed indirectly to girls' conduct problems by increasing the probability of involvement with deviant peers. Possible explanations for these gender differences are provided.

Economic stress, coercive family process, and developmental problems of adolescents.

We propose a model of family conflict and coercion that links economic stress in family life to adolescent symptoms of internalizing and externalizing emotions and behaviors. The 180 boys and 198 girls in the study were living in intact families in the rural Midwest, an area characterized by economic decline and uncertainty. Theoretical constructs in the model were measured using both trained observer and family member reports. These adolescents and their parents were interviewed each year for 3 years during the seventh, eighth, and ninth grades. Our theoretical model proposes that economic pressure experienced by parents increases parental dysphoria and marital conflict as well as conflicts between parents and children over money. High levels of spousal irritability, coupled with coercive exchanges over money matters, were expected to be associated with greater hostility in general by parents toward their children. These hostile/coercive exchanges were expected to increase the likelihood of adolescent emotional and behavioral problems. Overall, results were consistent with the proposed model. Moreover, the hypothesized processes applied equally well to the behavior of mothers and fathers, as well as sons and daughters.

Parents' stressful life events and adolescent depressed mood.

The present study of 451 families living in the rural Midwest examines a mediational model of the relationship between the stressful life events experienced by parents and adolescent depressed mood. This model is intended to overcome two limitations in previous research on the relationship between parents' stressful events and adolescent depressed mood by 1) examining a mediating process involving parental mood and parenting behavior, and 2) using multiple informants to assess the theoretical constructs. Findings from the present study indicate that stressful life events experienced by parents are first related to parents' depressed mood which operates to disrupt skillful parenting practices. The disrupted parenting practices in turn place adolescents at increased risk for developing depressive symptoms. The results show that inclusion of these mediating processes represents a significant improvement over the bivariate model and that the hypothesized mediational model generalizes to four parent-adolescent dyads: fathers and sons, fathers and daughters, mothers and sons, and mothers and daughters. Moreover, parents' stressful life events are related directly to adolescent boys' depressed mood only when parents' reports are included in both theoretical constructs. When parents' reports are removed as an indicator for the adolescent depressed mood construct, the effects of parental stress on adolescent depressed mood are largely accounted for by stress-related parental depressed mood and harsh/inconsistent parenting.

Husband and wife differences in response to undesirable life events.

In the present study of 451 married couples living in the rural midwest, gender differences were examined in reports of exposure and vulnerability to specific types of undesirable life events. Consistent with expectations derived from either a social structural or identity perspective, the results demonstrated that men are more likely than women to report exposure to and to be distressed by work and financial events. Women, on the other hand, are more strongly influenced by exposure to negative events within the family but not within their network of friends. Outcomes vary according to the type of emotional distress. Financial stress, for example, increases hostility among men more than among women, but wives are more likely than husbands to report somatic complaints in response to the same stressor. The findings demonstrate the need for future research that more directly investigates the intraindividual and social mechanisms which account for gender differences in a broad range of emotional and behavioral responses to varying types of significant life changes.

A comparison of adaptive strategies and patterns of victimization among homeless adolescents and adults.

One hundred and fifty-six homeless adolescents and 319 homeless adults interviewed directly on the streets and in shelters were compared for backgrounds of abuse, adaptations to life on the streets, and rates of criminal victimization when on the streets. Homeless adolescents were more likely to be from abusive family backgrounds, more likely to rely on deviant survival strategies, and more likely to be criminally victimized. A social learning model of adaptation and victimization on the streets was hypothesized. Although the model was supported for both homeless adults and adolescents, it was more strongly supported for adolescents than adults, and for males than females regardless of age.

Intergenerational continuity of parental rejection and depressed affect.

Using survey and observational data from a sample of 451 intact families, this study used structural equation modeling to examine the intergenerational continuity of depressed mood and rejecting parenting. The model partially replicated the intergenerational model of Elder, Caspi, and Downey (1986) that indicates a cyclical transmission process by which parents' personality traits affect parent-child interaction, which, in turn, increases the propensity for developmental problems among offspring. The results indicated a pattern of intergenerational transmission of depressed mood through parental rejection of offspring. Multiple reporters and multiple indicators strengthen previous intergenerational findings by reducing some of the method variance biases that have been problematic in prior studies.

Support from spouse as mediator and moderator of the disruptive influence of economic strain on parenting.

A model is presented regarding associations between economic strain, support from spouse, and quality of parenting. The model was tested using a sample of 451 2-parent families, each of which included a seventh grader (age 12-13). Parent and adolescent reports, as well as observational ratings, were used as indicators of constructs. Analysis using structural equation modeling procedures indicated that level of spouse support was positively related to supportive parenting, whereas economic strain operated to undermine parental involvement. As posited, economic strain produced its effect through a direct relation with parenting and indirectly through its association with spouse support. These findings held for mothers and fathers, regardless of the gender of the child. Spouse support moderated the impact of economic strain on supportive parenting for mothers but not fathers. Possible explanations for this gender difference are presented.

A family process model of economic hardship and adjustment of early adolescent boys.

We propose a family process model that links economic stress in family life to prosocial and problematic adolescent adjustment. Employing a sample of 205 seventh-grade boys aged 12 to 14 years (M = 12.7) and living in intact families in the rural Midwest, the theoretical constructs in the model were measured using both trained observer and family member reports. In general, results were consistent with the proposed model. Objective economic conditions such as per capita income and unstable work were related to parents' emotional status and behaviors through their perceptions of increased economic pressures such as the inability to pay monthly bills. These pressures were associated with depression and demoralization for both parents, which was related to marital conflict and disruptions in skillful parenting. Disrupted parenting mediated the relations between the earlier steps in the stress process and adolescent adjustment. The emotions and behaviors of both mothers and fathers were almost equally affected by financial difficulties, and disruptions in each parent's child-rearing behaviors had adverse consequences for adolescent development.

The effects of early family relationships on contemporary relationships and assistance patterns between adult children and their parents.

We investigated the influence of early parent-child relationships on contemporary adult child-parent relationships and the effects of these relationships on the level of assistance between adult child and parent. A sample of 902 married men and women were questioned regarding their current relationships with their elderly parents, the level of assistance provided them, and the quality of their relationship with their parents when they were growing up. The findings indicated that early parent-child relationships and the characteristics of parents when adult children were growing up influenced contemporary adult child-parent relationships. In turn, the quality of the contemporary adult child-parent relationship was found to have a slight effect on assistance from adult children to their parents.

Parenting factors, social skills, and value commitments as precursors to school failure, involvement with deviant peers, and delinquent behavior.

Elements of social control theory were combined with social learning theory to construct a model of delinquency which specifies the manner in which parenting factors, social skills, value commitments, and problems in school contribute to association with deviant peers and involvement in delinquent behavior. The model was tested using a sample of 61 families, each of which included a seventh grader. Questionnaire responses and coded videotaped family interaction were employed as measures of study constructs. The results largely supported the proposed model.