2,094 research outputs found
The Escherichia coli RutR transcription factor binds at targets within genes as well as intergenic regions.
The Escherichia coli RutR protein is the master regulator of genes involved in pyrimidine catabolism. Here we have used chromatin immunoprecipitation in combination with DNA microarrays to measure the binding of RutR across the chromosome of exponentially growing E. coli cells. Twenty RutR-binding targets were identified and analysis of these targets generated a DNA consensus logo for RutR binding. Complementary in vitro binding assays showed high-affinity RutR binding to 16 of the 20 targets, with the four low-affinity RutR targets lacking predicted key binding determinants. Surprisingly, most of the DNA targets for RutR are located within coding segments of the genome and appear to have little or no effect on transcript levels in the conditions tested. This contrasts sharply with other E. coli transcription factors whose binding sites are primarily located in intergenic regions. We suggest that either RutR has yet undiscovered function or that evolution has been slow to eliminate non-functional DNA sites for RutR because they do not have an adverse effect on cell fitness
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Linking metacognition and mindreading: Evidence from autism and dual-task investigations
Questions of how we know our own and other minds, and whether metacognition and mindreading rely on the same processes, are longstanding in psychology and philosophy. In Experiment 1, children/adolescents with autism (who tend to show attenuated mindreading) showed significantly lower accuracy on an explicit metacognition task than neurotypical children/adolescents, but not on an allegedly metacognitive implicit one. In Experiment 2, neurotypical adults completed these tasks in a single-task condition, or a dual-task condition that required concurrent completion of a secondary task that tapped mindreading. Metacognitive accuracy was significantly diminished by the dual-mindreading-task on the explicit task, but not the implicit task. In Experiment 3, we included additional dual-tasks to rule out the possibility that any secondary task (regardless of whether it required mindreading) would diminish metacognitive accuracy. Finally, in both experiments 1 and 2, metacognitive accuracy on the explicit task, but not the implicit task, was associated significantly with performance on a measure of mindreading ability. These results suggest that explicit metacognitive tasks (used frequently to measure metacognition in humans) share metarepresentational processing resources with mindreading, whereas implicit tasks (which are claimed by some comparative psychologists to measure metacognition in non-human animals) do not
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Metacognition, Metamemory, and Mindreading in High-Functioning Adults With Autism Spectrum Disorder
Objectives: Metacognition refers to cognition about cognition, and encompasses both knowledge of cognitive processes and the ability to monitor and control one’s own cognitions. The current study aimed to establish whether metacognition is impaired in autism spectrum disorder (ASD). According to some theories, the ability to represent one’s own mental states (an aspect of metacognition) relies on the same mechanism as the ability to represent others’ mental states (“mindreading”). Given numerous studies have shown mindreading is impaired in ASD, there is good reason to predict concurrent impairments in metacognition. Metacognition is most commonly explored in the context of memory, often by assessing people’s ability to monitor their memory processes. The current study addressed the question of whether people with ASD have difficulty monitoring the contents of their memory (alongside impaired mindreading).
Method: Eighteen intellectually high-functioning adults with ASD and 18 IQ- and age-matched neurotypical adults participated. Metamemory monitoring ability and mindreading ability were assessed using a feeling-of-knowing task and the “animations” task, respectively. Participants also completed a self-report measure of metacognitive ability.
Results: In addition to showing impaired mindreading, participants with ASD made significantly less accurate feeling-of-knowing judgements than neurotypical adults, suggesting that metamemory monitoring (an aspect of metacognition) was impaired. Conversely, participants with ASD self-reported superior metacognitive abilities compared to those reported by neurotypical participants.
Conclusion: This study provides evidence that individuals with ASD have metamemory monitoring impairments. The theoretical and practical implications of these findings for our current understanding of metacognition in ASD and typical development are discussed
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The self in autism and its relation to memory
This chapter begins with some definitions of memory and the self and continues to explain their relation on the psychological level along with their facets. It considers the relevance of these theories to autism spectrum disorder (ASD). The chapter provides a critical review of relevant research on the self in autism, followed by some hypotheses concerning how diminished sense of self might predict and explain the unique memory profile in the ASD population. Although there are a considerable number of studies showing typical performance on some types of “self” task among people with ASD on balance, existing evidence suggests that individuals with ASD have atypical me‐selves. There is a considerable amount of evidence to suggest that individuals with ASD have impaired episodic memory. Strikingly, the study of prospective memory in ASD is an emergent research field with a handful of studies published to date. Two forms of prospective memory are commonly distinguished: event‐based and time‐based
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The Self-reference Effect on Memory is Not Diminished in Autism: Three Studies of Incidental and Explicit Self-referential Recognition Memory in Autistic and Neurotypical Adults and Adolescents
Three experiments investigated the extent to which a) individuals with autism show a self-reference effect (i.e., better memory for self-relevant information), and b) the size of the self-reference effect is associated with autism traits. Participants studied trait adjectives in relation to their own name (self-referent) or a celebrity’s name (other-referent) under explicit and incidental/implicit encoding conditions. Explicit encoding involved judging whether the adjectives applied to self or other (denoted by proper names). Implicit encoding involved judging whether the adjectives were presented to the right or left of one’s own or a celebrity’s name. Recognition memory for the adjectives was tested using a yes/no procedure. Experiment 1 (individual differences; N = 257 neurotypical adults) employed the Autism-spectrum Quotient as a measure of autistic traits. Experiments 2 (N = 60) and 3 (N = 52) involved case-control designs with closely-matched groups of autistic and neurotypical adults and children/adolescents, respectively. Autistic traits were measured using the Autism-spectrum Quotient and Social Responsiveness Scale, respectively. In all experiments, a significant self-reference effect was observed in both explicit and implicit encoding conditions. Most importantly, however, there was (a) no significant relation between size of the self-reference effect and number of autistic traits (Experiments 1, 2 and 3), and (b) no significant difference in the size of the self-reference effect between autistic and neurotypical participants (Experiments 2 and 3). In these respects, Bayesian analyses consistently suggested that the data supported the null hypothesis. These results challenge the notion that subjective or objective self-awareness are impaired in autism. It is generally easier to remember information that is relevant to oneself than to remember other kinds of information. This is known as the “self-reference effect”. Previously, it has been claimed that people with autism show a reduced self-reference effect (implying diminished self-awareness) but this study provides robust evidence that people with autism are, in fact, just as susceptible to this effect as neurotypical people
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Relationships between implicit and explicit uncertainty monitoring and mindreading: Evidence from autism spectrum disorder
We examined performance on implicit (non-verbal) and explicit (verbal) uncertaintymonitoring tasks among neurotypical participants and participants with autism, while also testing mindreading abilities in both groups. We found that: (i) performance of autistic participants was unimpaired on the implicit uncertainty-monitoring task, while being significantly impaired on the explicit task; (ii) performance on the explicit task was correlated with performance on mindreading tasks in both groups, whereas performance on the implicit uncertainty-monitoring task was not; and (iii) performance on implicit and explicit uncertainty-monitoring tasks was not correlated. The results support the view that (a) explicit uncertainty-monitoring draws on the same cognitive faculty as mindreading whereas (b) implicit uncertainty-monitoring only test first-order decision making. These findings support the theory that metacognition and mindreading are underpinned by the same meta-representational faculty/resources, and that the implicit uncertainty-monitoring tasks that are frequently used with nonhuman animals fail to demonstrate the presence of metacognitive abilities
Strategies for measurement of atmospheric column means of carbon dioxide from aircraft using discrete sampling
[1] Automated flask sampling aboard small charter aircraft has been proposed as a low-cost, reliable method to greatly increase the density of measurements of CO2 mixing ratios in continental regions in order to provide data for assessment of global and regional CO2 budgets. We use data from the CO2 Budget and Rectification-Airborne 2000 campaign over North America to study the feasibility of using discrete ( flask) sampling to determine column mean CO2 in the lowest 4 km of the atmosphere. To simulate flask sampling, data were selected from profiles of CO2 measured continuously with an onboard ( in situ) analyzer. We find that midday column means can be determined without bias relative to true column means measured by the in situ analyzer to within 0.15 and better than 0.10 ppm by using 10 and 20 instantaneously collected flask samples, respectively. More precise results can be obtained by using a flask sampling strategy that linearly integrates over portions of the air column. Using less than 8 - 10 flasks can lead to significant sampling bias for some common profile shapes. Sampling prior to the breakup of the nocturnal stable layer will generally lead to large sampling bias because of the inability of aircraft to probe large CO2 gradients that often exist very close to the ground at night and during the early morning
Detailed analysis of data from heat pumps installed via the Renewable Heat Premium Payment Scheme
The RHPP policy provided subsidies for private householders, Registered social landlords and communities to install renewable heat measures in residential properties. Eligible measures included air and ground-source heat pumps, biomass boilers and solar thermal.
Around 18,000 heat pumps were installed via this scheme. DECC funded a detailed monitoring campaign, which covered 700 heat pumps (around 4% of the total). The aim of this monitoring campaign was to assess the efficiencies of the heat pumps and to estimate the carbon and bill savings and amount of renewable heat generated.
Data was collected from 31/10/2013 to 31/03/2015. This report represents the analysis of this data and represents the most complete and reliable data in-situ residential heat pump performance in the UK to date
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