Keepers Of The Light Conference 2000 Keynote Address

Donna Fletcher Crow is an author of historical fiction tracing the roots of Christianity in England, Scotland and Ireland. She delivered this keynote address for the opening session of the A CL Conference, Point Loma Nazarene University, San Diego, California, June 14, 200

Multiple markers of cortical morphology reveal evidence of supragranular thinning in schizophrenia.

In vivo structural neuroimaging can reliably identify changes to cortical morphology and its regional variation but cannot yet relate these changes to specific cortical layers. We propose, however, that by synthesizing principles of cortical organization, including relative contributions of different layers to sulcal and gyral thickness, regional patterns of variation in thickness of different layers across the cortical sheet and profiles of layer variation across functional hierarchies, it is possible to develop indirect morphological measures as markers of more specific cytoarchitectural changes. We developed four indirect measures sensitive to changes specifically occurring in supragranular cortical layers, and applied these to test the hypothesis that supragranular layers are disproportionately affected in schizophrenia. Our findings from the four different measures converge to indicate a predominance of supragranular thinning in schizophrenia, independent of medication and illness duration. We propose that these indirect measures offer novel ways of identifying layer-specific cortical changes, offering complementary in vivo observations to existing post-mortem studies.KW is supported by the University of Cambridge MB/PhD Programme and, together with KJW, by the Wellcome Trust. IMG by a Wellcome Trust Strategic Award (RNAG/260), and LR and PCF by the Bernard Wolfe Health Neuroscience Fund and Wellcome Trust

Differential tangential expansion as a mechanism for cortical gyrification.

Gyrification, the developmental buckling of the cortex, is not a random process-the forces that mediate expansion do so in such a way as to generate consistent patterns of folds across individuals and even species. Although the origin of these forces is unknown, some theories have suggested that they may be related to external cortical factors such as axonal tension. Here, we investigate an alternative hypothesis, namely, whether the differential tangential expansion of the cortex alone can account for the degree and pattern-specificity of gyrification. Using intrinsic curvature as a measure of differential expansion, we initially explored whether this parameter and the local gyrification index (used to quantify the degree of gyrification) varied in a regional-specific pattern across the cortical surface in a manner that was replicable across independent datasets of neurotypicals. Having confirmed this consistency, we further demonstrated that within each dataset, the degree of intrinsic curvature of the cortex was predictive of the degree of cortical folding at a global and regional level. We conclude that differential expansion is a plausible primary mechanism for gyrification, and propose that this perspective offers a compelling mechanistic account of the co-localization of cytoarchitecture and cortical folds

INTRINSIC CURVATURE: A MARKER OF MILLIMETER-SCALE TANGENTIAL CORTICO-CORTICAL CONNECTIVITY?

In this paper, we draw a link between cortical intrinsic curvature and the distributions of tangential connection lengths. We suggest that differential rates of surface expansion not only lead to intrinsic curvature of the cortical sheet, but also to differential inter-neuronal spacing. We propose that there follows a consequential change in the profile of neuronal connections: specifically an enhancement of the tendency towards proportionately more short connections. Thus, the degree of cortical intrinsic curvature may have implications for short-range connectivity

Stochastic evolutionary game dynamics

In this review, we summarize recent developments in stochastic evolutionary game dynamics of finite populations.Comment: To appear in "Reviews of Nonlinear Dynamics and Complexity" Vol. II, Wiley-VCH, 2009, edited by H.-G. Schuste

Job searching with a history of drugs and crime

This article explores the experiences and aspirations of offenders with histories of substance misuse in job searching. The analysis is based upon qualitative data from a localised study of 27 men and two women who were undertaking community-based court orders in Scotland. Their perspectives on job searching, job-readiness and aspirations for sustained employment including the role of self-employment are presented. The article concludes that with adequate support, greater tolerance and flexibility by employers and job searchers could contribute to reducing the vicious cycle of suspicion and dishonesty. Policy action needs to be sustained and possibly augmented to include enterprise training

Funny walking : the rise, fall and rise of the Anglo-American comic eccentric dancer

This article will attempt to reposition comic eccentric dance as a metamorphic form that still, surprisingly, exists, and is to be found with reasonable ubiquity, in renewed incarna-tions within twenty first century media. Tracing the origins of comic eccentric dance through examples of earlier comedy performance, and drawing from Bergson’s comic theory of body misalliance, this article will dis-cuss this particularly ludic fusion of music and comedy. Further changes to the form affected by modernist preoccupations during the new Jazz Age at the turn of the twentieth century will be suggested. Finally, ways in which the formulation lives on in twenty-first century in-carnations in the comedy work of, for instance, Jimmy Fallon and Ricky Gervase, and in popular television shows such as Strictly Come Dancing (BBC 2004 - ) and Britain’s Got Talent (ITV 2006 - ) will be posited

Identification of a signalling molecule involved in bacterial intergeneric communication

The development of complex multispecies communities such as biofilms is controlled by interbacterial communication systems. We have previously reported an intergeneric communication between two oral bacteria, Streptococcus cristatus and Porphyromonas gingivalis, that results in inhibition of fimA expression. Here, we demonstrate that a surface protein, arginine deiminase (ArcA), of S. cristatus serves as a signal that initiates intergeneric communication. An ArcA-deficient mutant of S. cristatus is unable to communicate with P. gingivalis. Furthermore, arginase activity is not essential for the communication, and ArcA retains the ability to repress expression of fimA in the presence of arginine deiminase inhibitors. These results present a novel mechanism by which intergeneric communication in dental biofilms is accomplished

Red Oak Seedlings as Indicators of Deer Browse Pressure: Gauging the Outcome of Different White-Tailed Deer Management Approaches

After decades of high deer populations, North American forests have lost much of their previous biodiversity. Any landscape‐level recovery requires substantial reduc‐ tions in deer herds, but modern societies and wildlife management agencies appear unable to devise appropriate solutions to this chronic ecological and human health crisis. We evaluated the effectiveness of fertility control and hunting in reducing deer impacts at Cornell University. We estimated spring deer populations and planted Quercus rubra seedlings to assess deer browse pressure, rodent attack, and other factors compromising seedling performance. Oak seedlings protected in cages grew well, but deer annually browsed ≥60% of unprotected seedlings. Despite female ster‐ ilization rates of \u3e90%, the deer population remained stable. Neither sterilization nor recreational hunting reduced deer browse rates and neither appears able to achieve reductions in deer populations or their impacts. We eliminated deer sterilization and recreational hunting in a core management area in favor of allowing volunteer arch‐ ers to shoot deer over bait, including at night. This resulted in a substantial reduction in the deer population and a linear decline in browse rates as a function of spring deer abundance. Public trust stewardship of North American landscapes will require a fundamental overhaul in deer management to provide for a brighter future, and oak seedlings may be a promising metric to assess success. These changes will re‐ quire intense public debate and may require new approaches such as regulated com‐ mercial hunting, natural dispersal, or intentional release of important deer predators (e.g., wolves and mountain lions). Such drastic changes in deer management will be highly controversial, and at present, likely difficult to implement in North America. However, the future of our forest ecosystems and their associated biodiversity will depend on evidence to guide change in landscape management and stewardship