277 research outputs found

    High potential for weathering and climate effects of non-vascular vegetation in the Late Ordovician

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    It has been hypothesized that predecessors of today’s bryophytes significantly increased global chemical weathering in the Late Ordovician, thus reducing atmospheric CO2 concentration and contributing to climate cooling and an interval of glaciations. Studies that try to quantify the enhancement of weathering by non-vascular vegetation, however, are usually limited to small areas and low numbers of species, which hampers extrapolating to the global scale and to past climatic conditions. Here we present a spatially explicit modelling approach to simulate global weathering by non-vascular vegetation in the Late Ordovician. We estimate a potential global weathering flux of 2.8 (km3 rock) yr−1, defined here as volume of primary minerals affected by chemical transformation. This is around three times larger than today’s global chemical weathering flux. Moreover, we find that simulated weathering is highly sensitive to atmospheric CO2 concentration. This implies a strong negative feedback between weathering by non-vascular vegetation and Ordovician climate

    Defining language impairments in a subgroup of children with autism spectrum disorder

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    Autism spectrum disorder (ASD) is diagnosed on the basis of core impairments in pragmatic language skills, which are found across all ages and subtypes. In contrast, there is significant heterogeneity in language phenotypes, ranging from nonverbal to superior linguistic abilities, as defined on standardized tests of vocabulary and grammatical knowledge. The majority of children are verbal but impaired in language, relative to age-matched peers. One hypothesis is that this subgroup has ASD and co-morbid specific language impairment (SLI). An experiment was conducted comparing children with ASD to children with SLI and typically developing controls on aspects of language processing that have been shown to be impaired in children with SLI: repetition of nonsense words. Patterns of performance among the children with ASD and language impairment were similar to those with SLI, and contrasted with the children with ASD and no language impairment and typical controls, providing further evidence for the hypothesis that a subgroup of children with ASD has co-morbid SLI. The findings are discussed in the context of brain imaging studies that have explored the neural bases of language impairment in ASD and SLI, and overlap in the genes associated with elevated risk for these disorders.M01 RR00533 - NCRR NIH HHS; R01 DC10290 - NIDCD NIH HHS; U19 DC03610 - NIDCD NIH HH

    Depression and Anxiety Change from Adolescence to Adulthood in Individuals with and without Language Impairment

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    This prospective longitudinal study aims to determine patterns and predictors of change in depression and anxiety from adolescence to adulthood in individuals with language impairment (LI). Individuals with LI originally recruited at age 7 years and a comparison group of age-matched peers (AMPs) were followed from adolescence (16 years) to adulthood (24 years). We determine patterns of change in depression and anxiety using the Child Manifest Anxiety Scale-Revised (CMAS-R) and Short Moods and Feelings Questionnaire (SMFQ). In addition to examining associations with gender, verbal and nonverbal skills, we use a time-varying variable to investigate relationships between depression and anxiety symptoms and transitions in educational/employment circumstances. The results show that anxiety was higher in participants with LI than age matched peers and remained so from adolescence to adulthood. Individuals with LI had higher levels of depression symptoms than did AMPs at 16 years. Levels in those with LI decreased post-compulsory schooling but rose again by 24 years of age. Those who left compulsory school provision (regardless of school type) for more choice-driven college but who were not in full-time employment or study by 24 years of age were more likely to show this depression pathway. Verbal and nonverbal skills were not predictive of this pattern of depression over time. The typical female vulnerability for depression and anxiety was observed for AMPs but not for individuals with LI. These findings have implications for service provision, career/employment advice and support for individuals with a history of LI during different transitions from adolescence to adulthood

    Environmental noise exposure, early biological risk and mental health in nine to ten year old children: a cross-sectional field study

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    <p>Abstract</p> <p>Background</p> <p>Previous research suggests that children born prematurely or with a low birth weight are more vulnerable to the mental health effects of ambient neighbourhood noise; predominantly road and rail noise, at home. This study used data from the Road Traffic and Aircraft Noise Exposure and Children's Cognition and Health (RANCH) study to see if this finding extends to aircraft and road traffic noise at school.</p> <p>Methods</p> <p>Children and their parents from schools around three European airports were selected to represent a range of aircraft and road traffic noise exposure levels. Birth weight and gestation period were merged to create a dichotomous variable assessing 'early biological risk'. Mental health was assessed using the Strengths and Difficulties Questionnaire (SDQ). Complete data were available for 1900 primary school children.</p> <p>Results</p> <p>Children who were 'at risk' (i.e. low birth weight or premature birth) were rated as having more conduct problems and emotional symptoms and poorer overall mental health than children not at risk. However, there was no interaction between aircraft or road traffic noise exposure at school and early biological risk.</p> <p>Conclusions</p> <p>Data from the RANCH study suggests that children with early biological risk are not more vulnerable to the effects of aircraft or road traffic noise at school on mental health than children without this risk; however they are more likely to have mental ill-health.</p

    Monsters: interdisciplinary explorations in monstrosity

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    There is a continued fascination with all things monster. This is partly due to the popular reception of Mary Shelley’s Monster, termed a “new species” by its overreaching but admiringly determined maker Victor Frankenstein in the eponymous novel first published in 1818. The enduring impact of Shelley’s novel, which spans a plethora of subjects and genres in imagery and themes, raises questions of origin and identity, death, birth and family relationships as well as the contradictory qualities of the monster. Monsters serve as metaphors for anxieties of aberration and innovation. Stephen Asma (2009) notes that monsters represent evil or moral transgression and each epoch, to speak with Michel Foucault, evidences a “particular type of monster” (2003, 66). Academic debates tend to explore how social and cultural threats come to be embodied in the figure of a monster and their actions literalize our deepest fears. Monsters in contemporary culture, however, have become are more humane than ever before. Monsters are strong, resilient, creative and sly creatures. Through their playful and invigorating energy they can be seen to disrupt and unsettle. They still cater to the appetite for horror, but they also encourage us to feel empathy. The encounter with a monster can enable us to stop, wonder and change our attitudes towards technology and our body and each other. This commentary article considers the use of the concepts of ‘monsters’ or ‘monstrosity’ in literature, contemporary research, culture and teaching contexts at the intersection of the Humanities and the Social Sciences

    ‘I already have a culture.’ Negotiating competing grand and personal narratives in interview conversations with new study abroad arrivals

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    In an interview with a postgraduate student about her intercultural experience of recently arriving for study abroad, it was found that the two researchers and the student were engaged in a mutual exploration of cultural identity. The in- terview events became conversational and took the form of small culture formation on the go in which each participant employed diverse narratives to project, make sense of and negotiate expression of cultural identity. The stu- dent shifted between personal narratives drawn from her particular cultural trajectories and splintered from grand narratives of nation and global position- ing, between non- essentialist threads and essentialist blocks. The researchers learned from her and intervened to facilitate shifts to non-essentialist threads, drawing on narratives from their own personal cultural trajectories, but some- times also falling into essentialist blocks splintered from grand narratives. The roles of ideology and competing essentialist and non-essentialist discourses of culture were implicit in these negotiations, as were the personal agency of the student as she responded to the constraining conflicts, structures and hierarchies encountered through the events she spoke about. Rather than providing a picture of intercultural assimilation and integration, interculturality is revealed as a hesitant and searching negotiation, sometimes of vulnerability, wrong-footedness and occasional assault on identity
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