7,280 research outputs found

    Selective disruption of stimulus-reward learning in glutamate receptor gria 1 knockout mice.

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    Glutamatergic neurotransmission via AMPA receptors has been an important focus of studies investigating neuronal plasticity. AMPA receptor glutamate receptor 1 (GluR1) subunits play a critical role in long-term potentiation (LTP). Because LTP is thought to be the cellular substrate for learning, we investigated whether mice lacking the GluR1 subunit [gria1 knock-outs (KO)] were capable of learning a simple cue-reward association, and whether such cues were able to influence motivated behavior. Both gria1 KO and wild-type mice learned to associate a light/tone stimulus with food delivery, as evidenced by their approaching the reward after presentation of the cue. During subsequent testing phases, gria1 KO mice also displayed normal approach to the cue in the absence of the reward (Pavlovian approach) and normal enhanced responding for the reward during cue presentations (Pavlovian to instrumental transfer). However, the cue did not act as a reward for learning a new behavior in the KO mice (conditioned reinforcement). This pattern of behavior is similar to that seen with lesions of the basolateral nucleus of the amygdala (BLA), and correspondingly, gria1 KO mice displayed impaired acquisition of responding under a second-order schedule. Thus, mice lacking the GluR1 receptor displayed a specific deficit in conditioned reward, suggesting that GluR1-containing AMPA receptors are important in the synaptic plasticity in the BLA that underlies conditioned reinforcement. Immunostaining for GluR2/3 subunits revealed changes in GluR2/3 expression in the gria1 KOs in the BLA but not the central nucleus of the amygdala (CA), consistent with the behavioral correlates of BLA but not CA function

    Values in teacher education: developing professional knowledge through engaging with trainee teachers’ personal moral and political values in the context of standards-based teacher education

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    Between 1989 -1997 I was head of the Religious Education department in a comprehensive school and mentored trainee teachers throughout that period. This meant that I was involved in the initial implementation of the first set of Teaching Standards set out in Circular 9/92 (DFE, 1992). As I progressed in the mentoring role I became increasingly aware of the challenge of meeting trainee’s training needs through a standards-based approach. In particular, I was aware of the importance of the role of the mentor in helping trainees to realise their personal values and motivations through their developing classroom practice. In researching my role for a research paper (Mead 1996) I reached the conclusion that the mentor’s self-understanding and their dialogic skills seemed to me to be crucial in developing the relationship between trainees’ personal moral and political values within their classroom practice, thereby contributing to a fusion of the moral and the instrumental within a standards-based framework. From 1997 until the present I have held a number of positions in the Department of Education at Oxford Brookes University, including Religious Education course leader, PGCE secondary course leader and head of the department of professional and leadership education. I am currently an associate School Direct university tutor. In these roles I have been fully immersed in the implementation of the 2002, 2007 and 2012 Teaching Standards for qualified teacher status, working closely with secondary and primary trainee teachers. The 2002 set of standards (Teacher Training Agency 2002) represented a landmark in that they introduced explicit professional values and this provided me with the impetus to continue to address those concerns which had emerged in my school mentor experience. It was through accumulated detailed knowledge and first-hand experience that I was increasingly able to interpret and make judgements about the impact of successive sets of prescribed teaching standards on the development of the relationship between trainees’ personal moral and political values. What I found emerging, then, is a sense of something of worth being at stake which has historical, political and professional implications and which is felt strongly enough by trainees and teacher educators to constitute an issue worthy of exploration. For me, as for many others who responded to my findings, the relationship between trainees’ personal moral and political values lies at the heart of professional fulfilment and consequently, the development of effective professional knowledge and expertise. The strength of the cohesiveness of the overall argument developed across the papers lies in my lived experience as the researcher who is also a practising teacher educator throughout the research period. Of particular importance here is both the immediacy and evolving nature of the research, as I respond personally and professionally to successive external measures affecting trainee teacher development. My overall aim has been to make sense of these experiences over more than thirteen years of professional experience. The outcome of this project is a set of claims which challenge key instrumentalist and positivistic features within expanding school-based teacher education, particularly in relation to trainee autonomy and identity and which, as I argue, have implications for re-defining process, pedagogy and provision

    Jupiter's radiation belts: Can Pioneer 10 survive?

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    Model calculations of Jupiter's electron and proton radiation belts indicate that the Galilean satellites can reduce particle fluxes in certain regions of the inner magnetosphere by as much as six orders of magnitude. Average fluxes should be reduced by a factor of 100 or more along the Pioneer 10 trajectory through the heart of Jupiter's radiation belts in early December. This may be enough to prevent serious radiation damage to the spacecraft

    Absorption of trapped particles by Jupiter's moons

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    Absorption effects of the four innermost moons in the radial transport equations for electrons and protons in Jupiter's magnetosphere are presented. The phase space density n at 2 R sub J for electrons with equatorial pitch angles less than 69 deg is reduced by a factor of 4.2 x 1000 when lunar absorption is included in the calculation. For protons with equatorial pitch angles less than 69 deg, the corresponding reduction factor is 3.2 x 100000. The effect of the satellites becomes progressively weaker for both electrons and protons as equatorial pitch angles of pi/2 are approached, because the likelihood of impacting a satellite becomes progressively smaller. The large density decreases which we find at the orbits of Io, Europa, and Ganymede result in corresponding particle flux decreases that should be observed by spacecraft making particle measurements in Jupiter's magnetosphere. The characteristic signature of satellite absorption should be a downward pointing cusp in the flux versus radius curve at the L-value corresponding to each satellite

    GPAQ-R: development and psychometric properties of a version of the general practice assessment questionnaire for use for revalidation by general practitioners in the UK.

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    BACKGROUND: The General Practice Assessment Questionnaire (GPAQ) has been widely used to assess patient experience in general practice in the UK since 2004. In 2013, new regulations were introduced by the General Medical Council (GMC) requiring UK doctors to undertake periodic revalidation, which includes assessment of patient experience for individual doctors. We describe the development of a new version of GPAQ - GPAQ-R which addresses the GMC's requirements for revalidation as well as additional NHS requirements for surveys that GPs may need to carry out in their own practices. METHODS: Questionnaires were given out by doctors or practice staff after routine consultations in line with the guidance given by the General Medical Council for surveys to be used for revalidation. Data analysis and practice reports were provided independently. RESULTS: Data were analysed for questionnaires from 7258 patients relating to 164 GPs in 29 general practices. Levels of missing data were generally low (typically 4.5-6%). The number of returned questionnaires required to achieve reliability of 0.7 were around 35 for individual doctor communication items and 29 for a composite score based on doctor communication items. This suggests that the responses to GPAQ-R had similar reliability to the GMC's own questionnaire and we recommend 30 completed GPAQ-R questionnaires are sufficient for revalidation purposes. However, where an initial screen raises concern, the survey might be repeated with 50 completed questionnaires in order to increase reliability. CONCLUSIONS: GPAQ-R is a development of a well-established patient experience questionnaire used in general practice in the UK since 2004. This new version can be recommended for use in order to meet the UK General Medical Council's requirements for surveys to be used in revalidation of doctors. It also meets the needs of GPs to ask about patient experience relating to aspects of practice care that are not specific to individual general practitioners (e.g. receptionists, telephone access) which meet other survey requirements of the National Health Service in England. Use of GPAQ-R has the potential to reduce the number of surveys that GPs need to carry out in their practices to meet the various regulatory requirements which they face

    Engineering of Low-Loss Metal for Nanoplasmonic and Metamaterials Applications

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    We have shown that alloying a noble metal (gold) with another metal (cadmium), which can contribute two electrons per atom to a free electron gas, can significantly improve the metals optical properties in certain wavelength ranges and make them worse in the other parts of the spectrum. In particular, in the gold-cadmium alloy we have demonstrated a significant expansion of the spectral range of metallic reflectance to shorter wavelengths. The experimental results and the predictions of the first principles theory demonstrate an opportunity for the improvement and optimization of low-loss metals for nanoplasmonic and metamaterials applications.Comment: 14 Pages, 4 figure

    Neural Filters for Jet Analysis

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    We study the efficiency of a neural-net filter and deconvolution method for estimating jet energies and spectra in high-background reactions such as nuclear collisions at the relativistic heavy-ion collider and the large hadron collider. The optimal network is shown to be surprisingly close but not identical to a linear high-pass filter. A suitably constrained deconvolution method is shown to uncover accurately the underlying jet distribution in spite of the broad network response. Finally, we show that possible changes of the jet spectrum in nuclear collisions can be analyzed quantitatively, in terms of an effective energy loss with the proposed method. {} {Dong D W and Gyulassy M 1993}{Neural filters for jet analysis} {(LBL-31560) Physical Review E Vol~47(4) pp~2913-2922}Comment: 21 pages of Postscript, (LBL-31560
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