1,973 research outputs found
(Re)framing the <i>Hortus</i>:an analysis of the boundaries of the Roman garden in the Late Republic and Early Empire
Understanding and use of small-scale models as representations of large-scale spaces, in 3 to 6 year old children: an investigation of the effects of varying task and method
Spatial representations are external, physical entities, which are used to symbolise real world environments. These kinds of symbols provide information about the world, and shape the way that we think about it. Previous research into children's
understanding and use of spatial representations has led to differing conclusions about how and when such abilities develop. This may be due to the diversity of different tasks and methods which have been adopted in the past. The aim of this thesis was to provide a systematic investigation of some of these tasks and methods, in order to establish whether they assess the same underlying abilities, and whether children perform similarly on all such tasks, using all such methods. A series of studies compared performance on two tasks - positioning and retrieval - and on two methods - inferring from a representation to a referent space, and from a referent space to a representation. Error data and time data were recorded in addition to success and failure. Results show that when target locations are completely concealed, levels of absolute success are similar on the two tasks. However, children take more time on the retrieval task, which may indicate a
difference in the way they approach tasks presented in a familiar game format.
Results also show that the two methods may not be equivalent. Performance
under these two methods differs in younger children particularly. Familiarity with
the referent space leads to improved performance when inferring from referent to
representation, and to more sophisticated response strategies overalL. The
presence of irrelevant material in either space does not affect performance.
Results support the notion that some representational understanding can be
achieved early in development, so representations of space can begin to be used from three years of age. However, despite this early achievement of
representational understanding, deficits in spatial cognition mean that the ability
to fully understand and use spatial representations is stil developing at 6 years of age
Evolution of Xenopus Tropicalis MC2R: Expression and Activation
The structure and functional relationship between the melanocortin-2 receptor (MC2R) and adrenocorticotropic hormone (ACTH) is the most complex of the melanocortin gene family. Prior studies had been done on amniote tetrapod MC2Rs (e.g., mammals); this study analyzed the expression and activation of MC2R by an anamniote tetrapod, Xenopus tropicalis (xtMC2R). An immunofluorescence approach, done on the expression of xtMC2R in Chinese Hamster Ovary cells (CHO cells), indicated that the trafficking of xtMC2R to the plasma membrane required co-expression with a tetrapod MRAP1(melanocortin-1 receptor accessory protein). A cAMP-reporter assay was used to show that xtMC2R can activated by human ACTH(1-24, but not by α-MSH. These two properties are also observed for human MC2R, and are common for tetrapod MC2Rs in general. Alanine-substitution analogs of hACTH(1-24) were used to deduce a possible mechanism for the activation of xtMC2R. These studies showed that alanine substitutions to the HFRW motif in hACTH(1-24) eliminated activation of the receptor. Furthermore, the alanine-substitution analysis revealed that positions 15 and 16 in the KKRRP motif are more important for the activation of xtMC2R than positions, 17 through 19. Finally, the alanine-substitution assays coupled with analysis of internally truncated analogs of the GKPVG motif resulted in decreased or complete elimination of xtMC2R activation. These data were used to construct a proposed three step model for the activation of MC2R. The final goal of this thesis was to identify the region of the receptor involved in the docking of the KKRRP motif of ACTH. Based on a model of MC2R, these experiments used alanine substitution site-directed mutagenesis to analyze the transmembrane 4 (TM4), extracellular loop 2 (EL2), and transmembrane 5 (TM5) region of xtMC2R. These experiments revealed that the following mutations had the greatest effect on the sensitivity (EC50 value) of xtMC2R: I/A175, F/A178, and I/A184. These results were compared to site-directed mutagenesis studies done on human and rainbow trout MC2Rs. Collectively, these analyses revealed that all three MC2Rs have docking sites for the KKRRP motif of ACTH that are similar in general location, and mostly similar in 3-dimensional structure, but that are not identical. The evolutionary implications of these observations are discussed
The Rising of a New Dawn in Africa: An Introduction to the African Continental Free Trade Area
There is a rising of a new dawn in African trade. The trade pattern of this region is set to change by the introduction of the African Continental Free Trade Area. This legal trade agreement moved by the African Union seeks to increase Intra - African Trade by creating a single market and allowing a free flow of people and goods has been postulated to curb the abnormality of ascending trading figures among African countries with countries from other continents as compared to the abysmal figures of trade among African countries. This academic piece seeks to unveil the African Continental Free Trade Area by highlighting its constituents, major strengths, challenges, expected impact and what it means for the international trading community. This academic piece seeks to present a simplified introduction to this agreement. Keywords: Intra - Africa, Trade agreement, Single market and Sustainable development. DOI: 10.7176/JAAS/54-08 Publication date: April 30th 201
The GO4KIDDS Brief Adaptive Scale
Background. Accurate measurement of adaptive behaviour is important in both clinical and research contexts. While several good clinical measures exist, as well as brief research measures for adults with ID, there is need for a brief and efficient measure for research with children and youth. We present preliminary psychometric properties of a new scale we developed for such purposes, the GO4KIDDS Brief Adaptive Behaviour Scale. Materials and Methods. A large sample (n=432) of parents of youth (aged 3 to 20) with ID and/or ASD completed an online survey that included the new scale. A subsample of these parents (n=204) also completed the Scales of Independent Behavior-Revised Short Form (Bruininks et al., 1996). Results. The new scale has good internal consistency and correlates strongly with the Scales of Independent Behavior, thus supporting its reliability and validity. Conclusions. Although we do not recommend its use for clinical purposes, the GO4KIDDS Brief Adaptive Behaviour Scale may be useful for survey research with parents of children and youth with developmental disabilities
Evaluating the Interaction Between the Human Melanocortin-2 Receptor and the Accessory Protein, Mrap1: Chimeric Receptor and Alanine Substitution Studies on Transmembrane Domain 4, Extracellular Loop 2, and Transmembrane Domain 5
The melanocortin-2 receptor (MC2R) is the most complex due to its trafficking and ligand selectivity requirements for proper activation. The MC2R requires the melanocortin receptor accessory protein-1 (MRAP1) for proper trafficking and activation of the receptor by the melanocortin hormone, ACTH. MRAP1 is a single transmembrane-spanning domain protein that creates a homodimer with another MRAP1 protein. Furthermore, MRAP2 creates a heterodimer with the MC2R. Previous studies have shown that the MRAP1 protein contains an activation motif required for activation of MC2R and this activation motif located on the extracellular space side of the plasma membrane of the cell. The objective of this dissertation was to analyze potential contact sites between the extracellular space side activation motif of MRAP1 with the extracellular domains of the MC2Râthe N-terminal, extracellular loop 1, extracellular loop 2, and extracellular loop 3. This analysis utilized a chimeric protein paradigm as well as alanine substitution experiments to observe potential contact sites between MRAP1 and the MC2R. By using these approaches, important residues required for trafficking or activation were identified in transmembrane 4, extracellular loop 2, and transmembrane 5 domains for MC2R. These results propose a revised mechanism for MC2R activation. Finally, the revised model suggests evolutionary implications for vertebrate MC2R activation
Predicting anxiety within atypical development
This thesis focusses on the issue of predicting anxiety in atypical populations, namely in autism spectrum disorder and in rare genetic syndromes.
The first chapter presents a systematic review of quantitative research conducted with the aim of identifying predictors of anxiety in people with autism spectrum disorder. Nineteen papers were included in the review. A wide range of predictors were identified and organised into eight salient themes including social skills, cognitive skills, emotional regulation and physiological responses. Predictors were identified as being both as direct and through mediation. A critique of the reviewed studies is given. The review raised questions about the methodology typically used to assess anxiety in autism research and areas for future research are suggested.
Chapter two presents a quantitative research study looking at the relationship between intolerance of uncertainty and anxiety in two rare genetic syndromes associated with autism spectrum disorder. Using questionnaire data, participants with Cornelia de Lange syndrome and Fragile X syndrome were compared on measures of anxiety, autism symptomatology and intolerance of uncertainty, and the relationships between these variables were examined. The findings of this study implicate intolerance of uncertainty in the presence of anxiety in both syndromes. In Cornelia de Lange syndrome, intolerance of uncertainty was found to mediate the relationship between autism symptoms and anxiety. Results are discussed in line with clinical and research implications.
The final chapter is the authorâs reflective account of conducting this research. The chapter reflects on the experience of conducting quantitative research as a trainee clinical psychologist and of managing the scientist-practitioner position whilst doing so. Reflections on the research process and the discovery of parallels with the authorâs clinical work are also discussed
To Learn About Science: Real Life Scientific Literacy Across Multicultural Communities
Much of the current research on scientific literacy focuses on particular text genres read by students within the classroom context. We offer a cross-case analysis of literacy as social practice in multicultural communities around the world, through which we reveal that individuals with no formal education, as well as people with varied levels of schooling completed, customarily and actively engage in literacy events with the goal of learning about science as part of their everyday lives. We argue that these outcomes substantiate the notion that multiple ways of being scientifically literate actually exist and that scientific literacy in its most fundamental sense is crucial in science education, despite the fact that the most common definitions and notions of scientific literacy have predominantly considered its derived sense (Norris and Phillips 224)
Orchestration of gene expression across the seasons : Hypothalamic gene expression in natural photoperiod throughout the year in the Siberian hamster
Acknowledgements Funding for work in the laboratory of PB was supported by Scottish Government Rural and Environment Science and Analytical Services Division, BBSRC (grant BB/M001504/1), British Society for Neuroendocrinology (research visit grant to IP). Work in the laboratory of SS was supported by a grant from the DFG (Ste 331/8-1). We thank Siegried Hilken, Marianne BrĂŒning, Dr. Esther Lipokatic-Takacs and Dr. Frank Scherbarth at UVMH for technical assistance. We thank Graham Horgan of Bioinformatics, Statistics Scotland for assistance with some of statistical tests.Peer reviewedPublisher PD
Salbutamol effects on systemic potassium dynamics during and following intense continuous and intermittent exercise
Purpose: Salbutamol inhalation is permissible by WADA in athletic competition for asthma management and affects potassium regulation, which is vital for muscle function. Salbutamol effects on arterial potassium concentration ([K+]a) during and after high-intensity continuous exercise (HIcont) and intermittent exercise comprising repeated, brief sprints (HIint), and on performance during HIint are unknown and were investigated. Methods: Seven recreationally active men participated in a double-blind, randomised, cross-over design, inhaling 1000 ”g salbutamol or placebo. Participants cycled continuously for 5 min at 40 % V Ë O2peak and 60 % V Ë O2peak, then HIcont (90 s at 130 % V Ë O2peak), 20 min recovery, and then HIint (3 sets, 5 Ă 4 s sprints), with 30 min recovery. Results: Plasma [K+]a increased throughout exercise and subsequently declined below baseline (P < 0.001). Plasma [K+]a was greater during HIcont than HIint (P < 0.001, HIcont 5.94 ± 0.65 vs HIint set 1, 4.71 ± 0.40 mM); the change in [K+]a from baseline (Î[K+]a) was 2.6-fold greater during HIcont than HIint (P < 0.001). The Î[K+] throughout the trial was less with salbutamol than placebo (P < 0.001, treatment main effect, 0.03 ± 0.67 vs 0.22 ± 0.69 mM, respectively); and remained less after correction for fluid shifts (P < 0.001). The Î[K+] during HIcont was less after salbutamol (P < 0.05), but not during HIint. Blood lactate, plasma pH, and the work output during HIint did not differ between trials. Conclusions: Inhaled salbutamol modulated the [K+]a rise across the trial, comprising intense continuous and intermittent exercise and recovery, lowering Î[K+] during HIcont. The limited [K+]a changes during HIint suggest that salbutamol is unlikely to influence systemic [K+] during periods of intense effort in intermittent sports
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