989 research outputs found

    A ‘Bad Fit’ for ‘Our’ Kids: Politics, Identity, Race and Power in Parental Discourse on Educational Programming & Child Well-being

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    Issues of race and class have long been at the center of discourses involving the American public education system. Although contemporary discourse regarding issues of race and power in American schools may be less overt in racist ideology than in previous decades, the impact of coded racist discourse can be equally powerful and dangerous. A need exists to identify racist and classist discourse in educational contexts so that the ideologies and practices these discourses reflect can be challenged. This paper uses critical discourse analysis and Critical Race Theory to examine how the discourses of race, class, and power are enacted within a discussion of educational programming and child well-being in a predominantly White, upper-middle class suburban public school

    An investigation of the meridional transport of potential energy

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    Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Meteorology, 1960.Includes bibliographical references (leaf 30).by Edward P. Sugrue.M.S

    Neural computations underlying action-based decision making in the human brain

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    Action-based decision making involves choices between different physical actions to obtain rewards. To make such decisions the brain needs to assign a value to each action and then compare them to make a choice. Using fMRI in human subjects, we found evidence for action-value signals in supplementary motor cortex. Separate brain regions, most prominently ventromedial prefrontal cortex, were involved in encoding the expected value of the action that was ultimately taken. These findings differentiate two main forms of value signals in the human brain: those relating to the value of each available action, likely reflecting signals that are a precursor of choice, and those corresponding to the expected value of the action that is subsequently chosen, and therefore reflecting the consequence of the decision process. Furthermore, we also found signals in the dorsomedial frontal cortex that resemble the output of a decision comparator, which implicates this region in the computation of the decision itself

    Immunocytochemical localization of the neuron-specific form of the c-src gene product, pp60c-src(+), in rat brain

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    Neurons express high levels of a variant form of the c-src gene product, denoted pp60c-src(+), which contains a 6 amino acid insert in the amino-terminal half of the c-src protein. We have determined the localization of pp60c-src(+) in neurons using an affinity-purified anti-peptide antibody, referred to as affi-SB12, that exclusively recognizes this neuron-specific form of the c-src gene product. Using affi-SB12, we examined the distribution of pp60c-src(+) by immunoperoxidase staining of sections through adult rat brains, pp60c-src(+) was widely distributed in rat brain and appeared to be differentially expressed in subpopulations of neurons. The majority of immunoreactive neurons was found in the mesencephalon, cerebellum, pons, and medulla. Telencephalic structures that contained substantial populations of pp60c-src(+)-immunoreactive neurons included layer V of the cerebral cortex and the ventral pallidum. Within individual neurons, pp60c-src(+) immunoreactivity was localized to the cell soma and dendritic processes, while labeling of axons and nerve terminals (puncta) was not as readily detected. Dense accumulations of immunoreactive axons were rare, being most prominent in portions of the inferior and superior olive, and in the spinal trigeminal nucleus. While the regional distribution of pp60c-src(+) immunoreactivity does not correlate with any specific neuronal cell type or first messenger system, this unique pattern of expression of pp60c-src(+) suggests the existence of a previously uncharacterized functional organization within the brain. Furthermore, the localization of this neuron-specific tyrosine kinase in functionally important areas of the nerve cell, namely, dendritic processes, axons, and nerve terminals, suggests that pp60c-src(+) may regulate pleiotropic functions in specific classes of neurons in the adult central nervous system

    Economic choices can be made using only stimulus values

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    Decision-making often involves choices between different stimuli, each of which is associated with a different physical action. A growing consensus suggests that the brain makes such decisions by assigning a value to each available option and then comparing them to make a choice. An open question in decision neuroscience is whether the brain computes these choices by comparing the values of stimuli directly in goods space or instead by first assigning values to the associated actions and then making a choice over actions. We used a functional MRI paradigm in which human subjects made choices between different stimuli with and without knowledge of the actions required to obtain the different stimuli. We found neural correlates of the value of the chosen stimulus (a postdecision signal) in ventromedial prefrontal cortex before the actual stimulus–action pairing was revealed. These findings provide support for the hypothesis that the brain is capable of making choices in the space of goods without first transferring values into action space

    Decoding the neural substrates of reward-related decision making with functional MRI

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    Although previous studies have implicated a diverse set of brain regions in reward-related decision making, it is not yet known which of these regions contain information that directly reflects a decision. Here, we measured brain activity using functional MRI in a group of subjects while they performed a simple reward-based decision-making task: probabilistic reversal-learning. We recorded brain activity from nine distinct regions of interest previously implicated in decision making and separated out local spatially distributed signals in each region from global differences in signal. Using a multivariate analysis approach, we determined the extent to which global and local signals could be used to decode subjects' subsequent behavioral choice, based on their brain activity on the preceding trial. We found that subjects' decisions could be decoded to a high level of accuracy on the basis of both local and global signals even before they were required to make a choice, and even before they knew which physical action would be required. Furthermore, the combined signals from three specific brain areas (anterior cingulate cortex, medial prefrontal cortex, and ventral striatum) were found to provide all of the information sufficient to decode subjects' decisions out of all of the regions we studied. These findings implicate a specific network of regions in encoding information relevant to subsequent behavioral choice

    Characterizing unmet medical need and the potential role of new biologic treatment options in patients with ulcerative colitis and Crohn's disease: a systematic review and clinician surveys

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    Objectives, Comparative outcomes of patients with ulcerative colitis, UC, and Crohn, s disease, CD, prescribed a biologic therapy are inconclusive. The aim of this research was to characterize the degree of unmet medical need in patients with UC or CD and to identify the potential role for new therapies. Methods, A systematic literature review was undertaken of studies reporting outcomes associated with the use of existing biologic therapies in patients with UC or CD, focusing on the nature and rate of treatment failure. To complement the systematic review, contemporaneous data were obtained from a survey of practising gastroenterologists in the UK and France. Data were qualitatively combined in a narrative framework to evaluate the degree of unmet medical need among patients with UC or CD. Results, Studies identified in the systematic review, n, were heterogeneous, particularly with respect to the definitions of treatment failure, estimates of treatment failure were high but uncertain. On the basis of standardized definitions, estimates of treatment failure provided by clinicians, n, were high, and they were higher for second-line treatment failure, primary, secondary, compared with first-line treatment failure, primary, secondary, . The majority of the systematic review and survey data were reflective of outcomes with infliximab and adalimumab. Conclusion, High treatment failure rates associated with existing biologics, identified by the review and clinician surveys, indicate a need for other biologic treatment options to improve the management and outcomes for people with UC and CD. Outcomes associated with existing and new biologic treatments should be investigated in head-to-head randomized trials in the context of their likely uses in clinical practice.Gordon, Jason P.a, e, McEwan, Phil C.a, b, Maguire, Andyc, Sugrue, Daniel M.a, Puelles, Jorge

    Transcript of The Dory Derby Accident

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    This story is an excerpt from a longer interview that was collected as part of the Launching through the Surf: The Dory Fleet of Pacific City project. In this story, Don Grotjohn recounts an accident that occurred during a Dory Derby competition

    Determining a Role for Ventromedial Prefrontal Cortex in Encoding Action-Based Value Signals During Reward-Related Decision Making

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    Considerable evidence has emerged to implicate ventromedial prefrontal cortex in encoding expectations of future reward during value-based decision making. However, the nature of the learned associations upon which such representations depend is much less clear. Here, we aimed to determine whether expected reward representations in this region could be driven by action–outcome associations, rather than being dependent on the associative value assigned to particular discriminative stimuli. Subjects were scanned with functional magnetic resonance imaging while performing 2 variants of a simple reward-related decision task. In one version, subjects made choices between 2 different physical motor responses in the absence of discriminative stimuli, whereas in the other version, subjects chose between 2 different stimuli that were randomly assigned to different responses on a trial-by-trial basis. Using an extension of a reinforcement learning algorithm, we found activity in ventromedial prefrontal cortex tracked expected future reward during the action-based task as well as during the stimulus-based task, indicating that value representations in this region can be driven by action–outcome associations. These findings suggest that ventromedial prefrontal cortex may play a role in encoding the value of chosen actions irrespective of whether those actions denote physical motor responses or more abstract decision options
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