Helen Brown

Bio: Helen Brown is an academic researcher from University of Warwick. The author has contributed to research in topics: Language acquisition & Lexical item. The author has an hindex of 12, co-authored 24 publications receiving 807 citations. Previous affiliations of Helen Brown include University of Bath & Nottingham Trent University.

Impacts of anthropogenic activity on the ecology of class 1 integrons and integron-associated genes in the environment

Abstract: The impact of human activity on the selection for antibiotic resistance in the environment is largely unknown, although considerable amounts of antibiotics are introduced through domestic wastewater and farm animal waste. Selection for resistance may occur by exposure to antibiotic residues or by co-selection for mobile genetic elements (MGEs) which carry genes of varying activity. Class 1 integrons are genetic elements that carry antibiotic and quaternary ammonium compound (QAC) resistance genes that confer resistance to detergents and biocides. This study aimed to investigate the prevalence and diversity of class 1 integron and integron-associated QAC resistance genes in bacteria associated with industrial waste, sewage sludge and pig slurry. We show that prevalence of class 1 integrons is higher in bacteria exposed to detergents and/or antibiotic residues, specifically in sewage sludge and pig slurry compared with agricultural soils to which these waste products are amended. We also show that QAC resistance genes are more prevalent in the presence of detergents. Studies of class 1 integron prevalence in sewage sludge amended soil showed measurable differences compared with controls. Insertion sequence elements were discovered in integrons from QAC contaminated sediment, acting as powerful promoters likely to upregulate cassette gene expression. On the basis of this data, >1 × 1019 bacteria carrying class 1 integrons enter the United Kingdom environment by disposal of sewage sludge each year.

Consolidation of vocabulary is associated with sleep in children

Abstract: Although the acquisition of a novel word is apparently rapid, adult research suggests that integration of novel and existing knowledge (measured by engagement in lexical competition) requires sleep-associated consolidation. We present the first investigation of whether a similar time-course dissociation characterizes word learning across development. Consistent with previous research but counter to adults, 7-12-year-olds showed sleep-associated consolidation effects in declarative but not procedural memory. Nevertheless, the relationship between sleep and word learning in children was remarkably similar to the pattern for adults. Following exposure to nonword competitors (e.g. biscal) in the a.m. or p.m., children's ability to recognize and recall the nonwords improved only after sleep (after approximately 12-hrs for the p.m. group and 24-hrs for the a.m. group), with performance stable 1 week later. Novel nonwords only induced lexical competition effects after sleep. These findings suggest that children utilize a dual memory system when acquiring and integrating new vocabulary and highlight sleep as integral to this process. A video abstract of this article can be viewed at http://www.youtube.com/watch?feature=youtube_gdata&v=2UNuKCAakOk&gl=GB.

Wellbeing and Society: Towards Quantification of the Co-benefits of Wellbeing

Abstract: The objectives of this paper are twofold. First, it reviews the empirical evidence showing the existence of linkage between wellbeing and possible co-benefits, investigating in particular the positive effect that happiness and life satisfaction can have on health, social outcomes, employment, education and environmental behaviours. Second, it presents the valuation methods that have been proposed in the literature to place a monetary value on these outcomes. With wellbeing having become more and more relevant for individuals and policy makers, the full understanding of the co-benefits of wellbeing is central for the design and development of wellbeing interventions. As a consequence, the evaluation of the co-benefits of wellbeing is of crucial importance for the appropriate allocation of resources towards such strategies.

About sleep's role in memory

Abstract: Over more than a century of research has established the fact that sleep benefits the retention of memory. In this review we aim to comprehensively cover the field of "sleep and memory" research by providing a historical perspective on concepts and a discussion of more recent key findings. Whereas initial theories posed a passive role for sleep enhancing memories by protecting them from interfering stimuli, current theories highlight an active role for sleep in which memories undergo a process of system consolidation during sleep. Whereas older research concentrated on the role of rapid-eye-movement (REM) sleep, recent work has revealed the importance of slow-wave sleep (SWS) for memory consolidation and also enlightened some of the underlying electrophysiological, neurochemical, and genetic mechanisms, as well as developmental aspects in these processes. Specifically, newer findings characterize sleep as a brain state optimizing memory consolidation, in opposition to the waking brain being optimized for encoding of memories. Consolidation originates from reactivation of recently encoded neuronal memory representations, which occur during SWS and transform respective representations for integration into long-term memory. Ensuing REM sleep may stabilize transformed memories. While elaborated with respect to hippocampus-dependent memories, the concept of an active redistribution of memory representations from networks serving as temporary store into long-term stores might hold also for non-hippocampus-dependent memory, and even for nonneuronal, i.e., immunological memories, giving rise to the idea that the offline consolidation of memory during sleep represents a principle of long-term memory formation established in quite different physiological systems.

Pharmaceuticals and personal care products in the environment: what are the big questions?

Abstract: Background: Over the past 10–15 years, a substantial amount of work has been done by the scientific, regulatory, and business communities to elucidate the effects and risks of pharmaceuticals and p...

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