45 research outputs found
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Actions and Words: Meaning Making in a Bilingual Arabic/English Kindergarten
Much research relating to bilingual education in the early years has focused on how young children are learning a new language, viewed from a monolingual paradigm of language use (Tabors 1997, Clarke 1999, Cummins 2001, Drury 2007, Genesee 2008). Recent sociocultural research on meaning-making in communities (García and Sylvan 2011, Gort and Sembiante 2015, Wei 2018, Creese and Blackledge 2019) reveals a less rigid boundary between named languages, and an emerging theory of translanguaging. This theory offers a new perspective from which to view pedagogical practices in bilingual classrooms.
The multimodal nature of young children’s meaning-making has long been acknowledged, founded on the work of Vygotsky in the 1920s, and is evident in the variety of pedagogical practices used by early years teachers to support meaning-making (Rogoff 1990, Siraj-Blatchford et al 2002). More recently, multimodal meaning-making has been explored in different communities (Kress 2000, Flewitt 2013, Bezemer and Kress 2014), revealing the many different modes of communication regularly employed to share meaning. However, in studies of early bilingual education, the significance of non-verbal behaviours has often been overlooked.
This thesis therefore sets out to explore the significance of multimodal meaning-making and a pedagogy for translingual practice (Canagarajah 2013) in an early years bilingual context. Using ethnographic tools, it analyses the pedagogical practices of two teachers working in a co-teaching situation in a kindergarten in Abu Dhabi. By an iterative process of data analysis, it explores how those practices contribute to children’s development as confident bilingual learners.
The findings indicate that, as teachers create new spaces for learning using action and gesture as well as speech, children are empowered to draw on both verbal and non-verbal modes of meaning-making in a fluid process of bilingual and multimodal languaging.
Emergent bilingualism, translanguaging, multimodality, sociocultural theory, early years, co-teaching, Arabian Gulf
Psychopathic and autistic traits differentially influence the neural mechanisms of social cognition from communication signals
Psychopathy is associated with severe deviations in social behavior and cognition. While previous research described such cognitive and neural alterations in the processing of rather specific social information from human expressions, some open questions remain concerning central and differential neurocognitive deficits underlying psychopathic behavior. Here we investigated three rather unexplored factors to explain these deficits, first, by assessing psychopathy subtypes in social cognition, second, by investigating the discrimination of social communication sounds (speech, non-speech) from other non-social sounds, and third, by determining the neural overlap in social cognition impairments with autistic traits, given potential common deficits in the processing of communicative voice signals. The study was exploratory with a focus on how psychopathic and autistic traits differentially influence the function of social cognitive and affective brain networks in response to social voice stimuli. We used a parametric data analysis approach from a sample of 113 participants (47 male, 66 female) with ages ranging between 18 and 40 years (mean 25.59, SD 4.79). Our data revealed four important findings. First, we found a phenotypical overlap between secondary but not primary psychopathy with autistic traits. Second, primary psychopathy showed various neural deficits in neural voice processing nodes (speech, non-speech voices) and in brain systems for social cognition (mirroring, mentalizing, empathy, emotional contagion). Primary psychopathy also showed deficits in the basal ganglia (BG) system that seems specific to the social decoding of communicative voice signals. Third, neural deviations in secondary psychopathy were restricted to social mirroring and mentalizing impairments, but with additional and so far undescribed deficits at the level of auditory sensory processing, potentially concerning deficits in ventral auditory stream mechanisms (auditory object identification). Fourth, high autistic traits also revealed neural deviations in sensory cortices, but rather in the dorsal auditory processing streams (communicative context encoding). Taken together, social cognition of voice signals shows considerable deviations in psychopathy, with differential and newly described deficits in the BG system in primary psychopathy and at the neural level of sensory processing in secondary psychopathy. These deficits seem especially triggered during the social cognition from vocal communication signals
Complementary resource use by tree species in a rain forest tree plantation
Mixed-species tree plantations, composed of high-value native rain forest timbers, are potential forestry systems for the subtropics and tropics that can provide ecological and production benefits. Choices of rain forest tree species for mixtures are generally based on the concept that assemblages of fast-growing and light-demanding species are less productive than assemblages of species with different shade tolerances. We examined the hypothesis that mixtures of two fast-growing species compete for resources, while mixtures of shade-tolerant and shade-intolerant species are complementary. Ecophysiological characteristics of young trees were determined and analyzed with a physiology-based canopy model (MAESTRA) to test species interactions. Contrary to predictions, there was evidence for complementary interactions between two fast-growing species with respect to nutrient uptake, nutrient use efficiency, and nutrient cycling. Fast-growing Elaeocarpus angustifolius had maximum demand for soil nutrients in summer, the most efficient internal recycling of N, and low P use efficiency at the leaf and whole-plant level and produced a large amount of nutrient-rich litter. In contrast, fast-growing Grevillea robusta had maximum demand for soil nutrients in spring and highest leaf nutrient use efficiency for N and P and produced low-nutrient litter. Thus, mixtures of fast-growing G. robusta and E. angustifolius or G. robusta and slow-growing, shade-tolerant Castanospermum australe may have similar or even greater productivity than monocultures, as light requirement is just one of several factors affecting performance of mixed-species plantations. We conclude that the knowledge gained here will be useful for designing large-scale experimental mixtures and commercial forestry systems in subtropical Australia and elsewhere
Anthropogenic forcing increases the water-use efficiency of African trees
Rising atmospheric CO2 concentrations affect climate directly through radiative effects and indirectly
by changing plant water-use efficiency. Under global warming scenarios these widely reported changes will have a
substantial impact on future bush encroachment, crop yields, river flow and climate feedbacks. Tree-ring intrinsic
water-use efficiency (iWUE) records for Africa show a 24.6% increase over the 20th century. As high iWUE can
partly counterbalance projected decreases in regional precipitation, this research has important implications for
those involved in water resource management and highlights the need for climate models to take physiological
forcing into account.National Geographic Society - Science and Exploration
Europe (grant GEFNE80-13), the Royal Geographical Society, the
Quaternary Research Association, the Palaeo-Anthropological Scientific Trust, the National Research Foundation, SysTem for Analysis, Research and Training (START) and the Climate Change Consortium of Wales.http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1099-14172017-05-31hb2016Mammal Research Institut
Climate change and epilepsy: insights from clinical and basic science studies
Climate change is with us. As professionals who place value on evidence-based practice, climate change is something we cannot ignore. The current pandemic of the novel coronavirus, SARS-CoV-2, has demonstrated how global crises can arise suddenly and have a significant impact on public health. Global warming, a chronic process punctuated by acute episodes of extreme weather events, is an insidious global health crisis needing at least as much attention. Many neurological diseases are complex chronic conditions influenced at many levels by changes in the environment. This review aimed to collate and evaluate reports from clinical and basic science about the relationship between climate change and epilepsy. The keywords climate change, seasonal variation, temperature, humidity, thermoregulation, biorhythm, gene, circadian rhythm, heat, and weather were used to search the published evidence. A number of climatic variables are associated with increased seizure frequency in people with epilepsy. Climate change-induced increase in seizure precipitants such as fevers, stress, and sleep deprivation (e.g. as a result of more frequent extreme weather events) or vector-borne infections may trigger or exacerbate seizures, lead to deterioration of seizure control, and affect neurological, cerebrovascular, or cardiovascular comorbidities and risk of sudden unexpected death in epilepsy. Risks are likely to be modified by many factors, ranging from individual genetic variation and temperature-dependent channel function, to housing quality and global supply chains. According to the results of the limited number of experimental studies with animal models of seizures or epilepsy, different seizure types appear to have distinct susceptibility to seasonal influences. Increased body temperature, whether in the context of fever or not, has a critical role in seizure threshold and seizure-related brain damage. Links between climate change and epilepsy are likely to be multifactorial, complex, and often indirect, which makes predictions difficult. We need more data on possible climate-driven altered risks for seizures, epilepsy, and epileptogenesis, to identify underlying mechanisms at systems, cellular, and molecular levels for better understanding of the impact of climate change on epilepsy. Further focussed data would help us to develop evidence for mitigation methods to do more to protect people with epilepsy from the effects of climate change. (C) 2021 Elsevier Inc. All rights reserved.Paroxysmal Cerebral Disorder
Neurocognitive dynamics of near-threshold voice signal detection and affective voice evaluation
Communication and voice signal detection in noisy environments are universal tasks for many species. The fundamental problem of detecting voice signals in noise (VIN) is underinvestigated especially in its temporal dynamic properties. We investigated VIN as a dynamic signal-to-noise ratio (SNR) problem to determine the neurocognitive dynamics of subthreshold evidence accrual and near-threshold voice signal detection. Experiment 1 showed that dynamic VIN, including a varying SNR and subthreshold sensory evidence accrual, is superior to similar conditions with nondynamic SNRs or with acoustically matched sounds. Furthermore, voice signals with affective meaning have a detection advantage during VIN. Experiment 2 demonstrated that VIN is driven by an effective neural integration in an auditory cortical-limbic network at and beyond the near-threshold detection point, which is preceded by activity in subcortical auditory nuclei. This demonstrates the superior recognition advantage of communication signals in dynamic noise contexts, especially when carrying socio-affective meaning.ISSN:2375-254
Categorizing human vocal signals depends on an integrated auditory‐frontal cortical network
Voice signals are relevant for auditory communication and suggested to be processed in dedicated auditory cortex (AC) regions. While recent reports highlighted an additional role of the inferior frontal cortex (IFC), a detailed description of the integrated functioning of the AC–IFC network and its task relevance for voice processing is missing. Using neuroimaging, we tested sound categorization while human participants either focused on the higher‐order vocal‐sound dimension (voice task) or feature‐based intensity dimension (loudness task) while listening to the same sound material. We found differential involvements of the AC and IFC depending on the task performed and whether the voice dimension was of task relevance or not. First, when comparing neural vocal‐sound processing of our task‐based with previously reported passive listening designs we observed highly similar cortical activations in the AC and IFC. Second, during task‐based vocal‐sound processing we observed voice‐sensitive responses in the AC and IFC whereas intensity processing was restricted to distinct AC regions. Third, the IFC flexibly adapted to the vocal‐sounds' task relevance, being only active when the voice dimension was task relevant. Forth and finally, connectivity modeling revealed that vocal signals independent of their task relevance provided significant input to bilateral AC. However, only when attention was on the voice dimension, we found significant modulations of auditory‐frontal connections. Our findings suggest an integrated auditory‐frontal network to be essential for behaviorally relevant vocal‐sounds processing. The IFC seems to be an important hub of the extended voice network when representing higher‐order vocal objects and guiding goal‐directed behavior
Does low-intensity surface fire increase water- and nutrient-availability to overstorey Eucalyptus gomphocephala?
The objective of this study was to investigate how the management practices of prescribed fire and understorey vegetation removal affect water and nutrient relations of old, yet prematurely declining Eucalyptus gomphocephala. Long unburnt sites were established in Yalgorup National Park, Western Australia, adjacent to frequently burnt state forest sites. Trees were allocated to vegetation clearing, prescribed fire or no prescribed fire treatments. Prescribed fire was achieved in only one long unburnt national park site so that the results were pseudoreplicated but analysed accordingly. Soil chemistry, plant nutrient availability and tree foliar carbon and nitrogen isotope ratio and nutrient concentration were investigated. No effects of vegetation clearing were found. Prescribed fire sites were associated with sky exposure and bare ground whereas no prescribed fire sites were associated with shrub and litter cover and litter depth. Foliar carbon isotope ratios were significantly more negative in prescribed fire, relative to no prescribed fire, treatments on long unburnt sites. Soil exchangeable Zn and Mn and plant available (estimated by charged resin beads) Mg were higher on prescribed fire, relative to no prescribed fire, long unburnt sites. Seedling bioassays indicated elevated P and Cu availability on prescribed fire, relative to no prescribed fire, treatments. In overstorey E. gomphocephala, foliar N levels were elevated (but not to excessive levels), and there was a trend toward elevated foliar Mn, in prescribed fire relative to no prescribed fire treatments on long unburnt sites. In the context of our large-scale pseudoreplicated case study, prescribed fire provided a pulse of water and N, (with some indications towards provision of elevated Mn, Cu and Mg) availability to E. gomphocephala in decline on sites with a history of a long absence of fire that may in part underpin observations of elevated tree health on sites that have a history of relatively frequent fire