Classification and Moral Evaluation of Uncertainties in Engineering Modeling

Engineers must deal with risks and uncertainties as a part of their professional work and, in particular, uncertainties are inherent to engineering models. Models play a central role in engineering. Models often represent an abstract and idealized version of the mathematical properties of a target. Using models, engineers can investigate and acquire understanding of how an object or phenomenon will perform under specified conditions. This paper defines the different stages of the modeling process in engineering, classifies the various sources of uncertainty that arise in each stage, and discusses the categories into which these uncertainties fall. The paper then considers the way uncertainty and modeling are approached in science and the criteria for evaluating scientific hypotheses, in order to highlight the very different criteria appropriate for the development of models and the treatment of the inherent uncertainties in engineering. Finally, the paper puts forward nine guidelines for the treatment of uncertainty in engineering modeling.     

Association between morningness-eveningness and mental and physical health in adolescents

Individuals differ in their biological rhythms and their preference for morning or evening hours. Morning types prefer morning hours for intellectual and physical activities while evening types feel and perform best at late afternoon or in the evening. This not only is a simple dichotomous classification but also can be viewed as a continuum. Individual differences in morningness-eveningness are an interesting facet of personality, but little is known about the relationship between psychological factors or health-related variables and morningness-eveningness in adolescents. In Study I, there were positive correlations between morningness and positive attitude towards life and a negative association between morningness and depression. In Study II, there were significant positive relationships between morningness and physical health, mental health, self-esteem, familial relationship, and school functioning. These results indicate that eveningness might be an unspecific risk factor for mental and physical health.     

The psychological well-being of employees who handle cash in a bank in inner city Johannesburg

The aim of the study was to compare the psychological well-being of bank employees who handled cash and those who did not. The study assessed employees' levels of work stress, burnout and life satisfaction. The Job Stress Survey Scale was used to measure work stress, Maslach Burnout Inventory was used to measure burnout and the Congruity Life Satisfaction Scale was used to measure life satisfaction. Two independent sample t tests were run on Statistical Analysis Software. The results showed that the two groups differed significantly in terms of work stress, emotional exhaustion, depersonalisation and overall burnout. The findings of this study suggest the need for organisational support, skills development and the provision of wellness programmes for bank employees.     

HIV and depression--a systematic review of interventions

HIV-positive individuals are more likely to be diagnosed with major depressive disorder than HIV-negative individuals. Depression can precede diagnosis and be associated with risk factors for infection. The experience of illness can also exacerbate depressive episodes and depression can be a side effect to treatment. A systematic understanding of which interventions have been tested in and are effective with HIV-seropositive individuals is needed. This review aims to provide a comprehensive understanding of evaluated interventions related to HIV and depression and provide some insight on questions of prevalence and measurement. Standard systematic research methods were used to gather quality published papers on HIV and depression. From the search, 1015 articles were generated and hand searched resulting in 90 studies meeting adequacy inclusion criteria for analysis. Of these, 67 (74.4%) were implemented in North America (the US and Canada) and 14 (15.5%) in Europe, with little representation from Africa, Asia and South America. Sixty-five (65.5%) studies recruited only men or mostly men, of which 31 (35%) recruited gay or bisexual men. Prevalence rates of depression ranged from 0 to 80%; measures were diverse and rarely adopted the same cut-off points. Twenty-one standardized instruments were used to measure depression. Ninety-nine interventions were investigated. The interventions were diverse and could broadly be categorized into psychological, psychotropic, psychosocial, physical, HIV-specific health psychology interventions and HIV treatment-related interventions. Psychological interventions were particularly effective and in particular interventions that incorporated a cognitive-behavioural component. Psychotropic and HIV-specific health psychology interventions were generally effective. Evidence is not clear-cut regarding the effectiveness of physical therapies and psychosocial interventions were generally ineffective. Interventions that investigated the effects of treatments for HIV and HIV-associated conditions on depression generally found that these treatments did not increase but often decreased depression. Interventions are both effective and available, although further research into enhancing efficacy would be valuable. Depression needs to be routinely logged in those with HIV infection during the course of their disease. Specific data on women, young people, heterosexual men, drug users and those indiverse geographic areas are needed. Measurement of depression needs to be harmonized and management into care protocols incorporated.     

Children's beliefs about the fantasy/reality status of hypothesized machines

Four-year-olds, 6-year-olds, and adults were asked to make judgments about the reality status of four different types of machines: real machines that children and adults interact with on a daily basis, real machines that children and adults interact with rarely (if at all), and impossible machines that violated a real-world physical or biological causal law. Adults generally categorized all of the machines accurately. Both groups of children categorized familiar possible machines as real, but were agnostic as to the fantasy status of unfamiliar possible machines. Children generally responded that both kinds of impossible machines were make-believe, but 4-year-olds were more likely to make these accurate judgments for the physical than biological items, different from the older children and adults (whose responses were similar). These data suggest that children's judgments about the possibility of machines are not strictly limited by first-hand experience. Young children's domain-specific causal knowledge interacts with their understanding of the fantasy/reality distinction to constrain their inferences in a rational way.     

An image is worth a thousand words: why nouns tend to dominate verbs in early word learning

Nouns are generally easier to learn than verbs (e.g., Bornstein, 2005; Bornstein et al., 2004; Gentner, 1982; Maguire, Hirsh-Pasek, & Golinkoff, 2006). Yet, verbs appear in children's earliest vocabularies, creating a seeming paradox. This paper examines one hypothesis about the difference between noun and verb acquisition. Perhaps the advantage nouns have is not a function of grammatical form class but rather related to a word's imageability. Here, word imageability ratings and form class (nouns and verbs) were correlated with age of acquisition according to the MacArthur-Bates Communicative Development Inventory (CDI) (Fenson et al., 1994). CDI age of acquisition was negatively correlated with words' imageability ratings. Further, a word's imageability contributes to the variance of the word's age of acquisition above and beyond form class, suggesting that at the beginning of word learning, imageability might be a driving factor.     

The association between infants' self-regulatory behavior and MAOA gene polymorphism

Self-regulatory behavior in early childhood is an important characteristic that has considerable implications for the development of adaptive and maladaptive functioning. The present study investigated the relations between a functional polymorphism in the upstream region of monoamine oxidase A gene (MAOA) and self-regulatory behavior in a sample of Chinese infants at 6 months of age. Self-regulation was assessed by observing infants' behavior of orienting visual attention away from a threatening event in the laboratory situation. The results indicated that regulatory behavior was associated with the functional MAOA gene polymorphism in girls, but not boys. Girls with 4/4 genotypes displayed significantly higher regulation than girls with 3/3 and 3/4 genotypes. The present study provided evidence for gender differences on the role of MAOA gene polymorphism in socioemotional functioning in the early years.     

Toddlers with Autism Spectrum Disorder are more successful at visual search than typically developing toddlers

Plaisted, O'Riordan and colleagues (Plaisted, O'Riordan & Baron-Cohen, 1998; O'Riordan, 2004) showed that school-age children and adults with Autism Spectrum Disorder (ASD) are faster at finding targets in certain types of visual search tasks than typical controls. Currently though, there is very little known about the visual search skills of very young children (1-3-year-olds) - either typically developing or with ASD. We used an eye-tracker to measure looking behavior, providing fine-grained measures of visual search in 2.5-year-old toddlers with and without ASD (this representing the age by which many children may first receive a diagnosis of ASD). Importantly, our paradigm required no verbal instructions or feedback, making the task appropriate for toddlers who are pre- or nonverbal. We found that toddlers with ASD were more successful at finding the target than typically developing, age-matched controls. Further, our paradigm allowed us to estimate the number of items scrutinized per trial, revealing that for large set size conjunctive search, toddlers with ASD scrutinized as many as twice the number of items as typically developing toddlers, in the same amount of time.     

Monkeys represent others' knowledge but not their beliefs

The capacity to reason about the false beliefs of others is classically considered the benchmark for a fully fledged understanding of the mental lives of others. Although much is known about the developmental origins of our understanding of others' beliefs, we still know much less about the evolutionary origins of this capacity. Here, we examine whether non-human primates - specifically, rhesus macaques (Macaca mulatta) - share this developmental achievement. We presented macaques with a looking-time measure of false belief understanding, one that had recently been developed for use with 15-month-old human infants. Like human infants, monkeys look longer when a human experimenter fails to search in the correct location when she has accurate knowledge. In contrast to infants, however, monkeys appear to make no prediction about how a human experimenter will act when she has a false belief. Across three studies, macaques' pattern of results is consistent with the view that monkeys can represent the knowledge and ignorance of others, but not their beliefs. The capacity to represent beliefs may therefore be a unique hallmark of human cognition.