Behavioural Consequences of Frontal Cortex Grafts and Enriched Environments after Sensorimotor Cortex Lesions

Past studies have experienced difficulty in achieving graft survival and behavioural recovery after sensorimotor cortex lesions. In the present work, adult female rats trained preoperatively to cross a narrow beam for food reward were maintained in standard group cages or an enriched environment, commencing one week after a unilateral lesion. One month post-lesion, half of these rats received multiple suspension grafts of (E20) fetal frontal cortex, placed adjacent to the lesion cavity, and 8 days later recovery of beam-walking skills was examined for a six-week period. The grafts survived in all cases with an appropriate lesion, a notable result given the one month lesion-graft delay, but graft volume was not influenced by postoperative environment. The substantial lesion-induced deficits evident just prior to differential housing showed a marked reduction by the start of post-graft testing, but relative to intact controls a persistent deficit in foot slip errors occurred in all lesion groups. Irrespective of graft status, postoperative enrichment prevented the occurrence of severe foot slips, especially early in retraining. The frontal grafts, however, enhanced beam-walking recovery by reducing the overall frequency of foot slips on early post-grafting sessions, an effect we suggest is related to graft-derived trophic influences, but this measure was not significantly improved by postoperative enrichment

Interactions of scope and ellipsis

Systematic semantic ambiguities result from the interaction of the two operations that are involved in resolving ellipsis in the presence of scoping elements such as quantifiers and intensional operators: scope determination for the scoping elements and resolution of the elided relation. A variety of problematic examples previously noted - by Sag, Hirschbüihler, Gawron and Peters, Harper, and others - all have to do with such interactions. In previous work, we showed how ellipsis resolution can be stated and solved in equational terms. Furthermore, this equational analysis of ellipsis provides a uniform framework in which interactions between ellipsis resolution and scope determination can be captured. As a consequence, an account of the problematic examples follows directly from the equational method. The goal of this paper is merely to point out this pleasant aspect of the equational analysis, through its application to these cases. No new analytical methods or associated formalism are presented, with the exception of a straightforward extension of the equational method to intensional logic.Engineering and Applied Science

The thalamic reuniens is associated with consolidation of non-spatial memory too

The nucleus reuniens (RE) is situated in the midline thalamus and provides a key link between the hippocampus and prefrontal cortex. This anatomical relationship positions the Re as an ideal candidate to facilitate memory consolidation. However, there is no evidence that this role extends beyond spatial memory and contextual fear memory, which are both strongly associated with hippocampal function. We, therefore, trained intact male Long–Evans rats on an odor–trace–object paired-associate task where the explicit 10-s delay between paired items renders the task sensitive to hippocampal function. Neurons in the RE showed significantly increased activation of the immediate early gene (Zif268) when rats were re-tested for previous non-spatial memory 25 days after acquisition training, compared to a group tested at 5-days post-acquisition, as well as a control group tested 25 days after acquisition but with a new pair of non-spatial stimuli, and home cage controls. The remote recall group also showed relatively augmented IEG expression in the superficial layers of the medial PFC (anterior cingulate cortex and prelimbic cortex). These findings support the conclusion that the RE is preferentially engaged during remote recall in this non-spatial task and thus has a role beyond spatial memory and contextual fear memory

Experimental study of nearshore dynamics on a barred beach with rip channels

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95201/1/jgrc8777.pd

Characterising work-based learning as a triadic learning endeavour

With work-based learning (WBL) forming an increasingly prevalent dimension of modern higher education practice, conceptual models of the pedagogies underpinning WBL are increasingly emerging. There is broadening recognition of the need to capture and represent the values and presuppositions underlying WBL in order to support facilitators and learners engaged in WBL for the first time. Accordingly, the current study proposes a new characterisation of WB higher education which can helpfully inform the design and delivery of WBL curricula, schemes of work and teaching and learning strategies. Informed by the authors' extensive facilitation of WBL programmes for such diverse fields of professional practice as dance teaching, event management, security and the military, the model represents WBL as a triadic learning endeavour in which student, work-based facilitator and university tutor are engaged in a mode of learning which is best conceived as ‘academy-aligned' rather than ‘academy-based', and in which the signature pedagogic principle is one of ‘responsive facilitation'. The application of the model in a number of programmes is demonstrated and some recommendations for WB practice outlined

Analysis of the complement and molecular evolution of tRNA genes in cow

<p>Abstract</p> <p>Background</p> <p>Detailed information regarding the number and organization of transfer RNA (tRNA) genes at the genome level is becoming readily available with the increase of DNA sequencing of whole genomes. However the identification of functional tRNA genes is challenging for species that have large numbers of repetitive elements containing tRNA derived sequences, such as <it>Bos taurus</it>. Reliable identification and annotation of entire sets of tRNA genes allows the evolution of tRNA genes to be understood on a genomic scale.</p> <p>Results</p> <p>In this study, we explored the <it>B. taurus </it>genome using bioinformatics and comparative genomics approaches to catalogue and analyze cow tRNA genes. The initial analysis of the cow genome using tRNAscan-SE identified 31,868 putative tRNA genes and 189,183 pseudogenes, where 28,830 of the 31,868 predicted tRNA genes were classified as repetitive elements by the RepeatMasker program. We then used comparative genomics to further discriminate between functional tRNA genes and tRNA-derived sequences for the remaining set of 3,038 putative tRNA genes. For our analysis, we used the human, chimpanzee, mouse, rat, horse, dog, chicken and fugu genomes to predict that the number of active tRNA genes in cow lies in the vicinity of 439. Of this set, 150 tRNA genes were 100% identical in their sequences across all nine vertebrate genomes studied. Using clustering analyses, we identified a new tRNA-Gly^CCCsubfamily present in all analyzed mammalian genomes. We suggest that this subfamily originated from an ancestral tRNA-Gly^GCCgene via a point mutation prior to the radiation of the mammalian lineages. Lastly, in a separate analysis we created phylogenetic profiles for each putative cow tRNA gene using a representative set of genomes to gain an overview of common evolutionary histories of tRNA genes.</p> <p>Conclusion</p> <p>The use of a combination of bioinformatics and comparative genomics approaches has allowed the confident identification of a set of cow tRNA genes that will facilitate further studies in understanding the molecular evolution of cow tRNA genes.</p