Systems Analysis as a Decision-Making Tool for the Library Manager

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Heavy Fermion Stabilization of Solitons in 1+1 Dimensions

We find static solitons stabilized by quantum corrections in a (1+1)-dimensional model with a scalar field chirally coupled to fermions. This model does not support classical solitons. We compute the renormalized energy functional including one-loop quantum corrections. We carry out a variational search for a configuration that minimizes the energy functional. We find a nontrivial configuration with fermion number whose energy is lower than the same number of free fermions quantized about the translationally invariant vacuum. In order to compute the quantum corrections for a given background field we use a phase-shift parameterization of the Casimir energy. We identify orders of the Born series for the phase shift with perturbative Feynman diagrams in order to renormalize the Casimir energy using perturbatively determined counterterms. Generalizing dimensional regularization, we demonstrate that this procedure yields a finite and unambiguous energy functional.Comment: 27 papes Latex, equation labels corrected, version to be published in Nucl. Phys.

Multimodal, Multidimensional Models of Mouse Brain

Naturally occurring mutants and genetically manipulated strains of mice are widely used to model a variety of human diseases. Atlases are an invaluable aid in understanding the impact of such manipulations by providing a standard for comparison and to facilitate the integration of anatomic, genetic, and physiologic observations from multiple subjects and experiments. We have developed digital atlases of the C57BL/6J mouse brain (adult and neonate) as comprehensive frameworks for storing and accessing the myriad types of information about the mouse brain. Along with raw and annotated images, these contain database management systems and a set of tools for comparing information from different techniques and different animals. Each atlas establishes a canonical representation of the mouse brain and provides the tools for the manipulation and analysis of new data. We describe both these atlases and discuss how they may be put to use in organizing and analyzing data from mouse models of epilepsy

Can the TV makeover format of edutainment lead to widespread changes in farmer behaviour and influence innovation systems? Shamba Shape Up in Kenya

Edutainment, the combination of education with entertainment through various media such as television, radio, mobile phone applications and games, is increasingly being used as an approach to stimulate innovation and increase agricultural productivity amongst smallholder farmers in sub-Saharan Africa. Shamba Shape Up, a widely publicised makeover reality TV programme, is an example of edutainment that has received considerable attention, and airs in three countries in East Africa where it is estimated to be watched by millions of viewers. There is no published academic research on the influence of makeover television formats on innovation systems and processes in smallholder agriculture. Using an Agricultural Innovation Systems approach, this paper explores how makeover edutainment is influencing smallholder farmer innovation systems together with the effect this is having on smallholder farms. In the absence of previous research, it articulates a Theory of Change which draws on research traditions from mass communication, agricultural extension and innovation systems. Data came from two large scale quantitative (n=9,885 and n=1,572) surveys and in-depth participatory qualitative research comprising focus group discussions, participatory budgets, agricultural timelines, case studies and key information interviews in Kenya. An estimated 430,000 farmers in the study area were benefiting from their interaction with the programme through increased income and / or a range of related social benefits including food security, improving household health, diversification of livelihood choices, paying school fees for children and increasing their community standing / social capital. Participatory research showed SSU enhanced an already rich communication environment and strengthened existing processes of innovation. It helped set the agenda for discussions within farming communities about opportunities for improving smallholder farms, while also giving specific ideas, information and knowledge, all in the context of featured farm families carefully selected so that a wide range of viewers would identify with them and their challenges. Broadcasts motivated and inspired farmers to improve their own farms through a range of influences including entertainment, strong empathy with the featured host farm families, the way ideas emerged through interaction with credible experts, and importantly through stimulating widespread discussion and interaction amongst and between farmers and communities of experts on agricultural problems, solutions and opportunities. The fact that local extension workers also watched the programmes further enhanced the influence on local innovation systems. The findings indicate that well designed makeover edutainment can strongly influence agricultural innovation processes and systems resulting in impact on the agricultural production and behaviours of large numbers of smallholder farmers

Electrophysiological investigations of recognition memory: The role of pre-existing representations in recollection

Dual-process models of recognition memory propose that recognition memory can be supported by either a general sense of familiarity or the recollection of the encoding context. One source of evidence supporting dual-process models comes from event-related potential (ERP) studies of recognition memory, which have identified distinct patterns of neural activity associated with familiarity and recollection (the mid frontal and left parietal old/new effects, respectively). In this thesis, dual-process accounts of recognition memory were investigated in a series of ERP studies using three categories of stimulus: previously unknown faces, famous faces, and names. For previously unknown faces, familiarity was associated with activity over posterior scalp electrodes while recollection was associated with topographically dissociable activity over anterior electrodes. These dissociable patterns of activity support dual-process models. However, the typical pattern of old/new effects was only observed for stimuli associated with pre-existing representations (i.e., names and famous faces), suggesting that the presence/absence of pre-existing representations may determine the particular retrieval processes that support recognition memory. Furthermore, recollection was associated with two different patterns of activity (anterior and left parietal effects), suggesting that recollection is not a homogenous process. Dual-process theories may represent an important starting point for investigating recognition memory, but neither familiarity nor recollection appear to be functionally homogenous processes when theorizing is constrained by the analysis of scalp recorded electrophysiological activity

Ischemic axonal injury up-regulates MARK4 in cortical neurons and primes tau phosphorylation and aggregation.

Ischemic injury to white matter tracts is increasingly recognized to play a key role in age-related cognitive decline, vascular dementia, and Alzheimer's disease. Knowledge of the effects of ischemic axonal injury on cortical neurons is limited yet critical to identifying molecular pathways that link neurodegeneration and ischemia. Using a mouse model of subcortical white matter ischemic injury coupled with retrograde neuronal tracing, we employed magnetic affinity cell sorting with fluorescence-activated cell sorting to capture layer-specific cortical neurons and performed RNA-sequencing. With this approach, we identified a role for microtubule reorganization within stroke-injured neurons acting through the regulation of tau. We find that subcortical stroke-injured Layer 5 cortical neurons up-regulate the microtubule affinity-regulating kinase, Mark4, in response to axonal injury. Stroke-induced up-regulation of Mark4 is associated with selective remodeling of the apical dendrite after stroke and the phosphorylation of tau in vivo. In a cell-based tau biosensor assay, Mark4 promotes the aggregation of human tau in vitro. Increased expression of Mark4 after ischemic axonal injury in deep layer cortical neurons provides new evidence for synergism between axonal and neurodegenerative pathologies by priming of tau phosphorylation and aggregation