2,815 research outputs found
EMX2 regulates sizes and positioning of the primary sensory and motor areas in neocortex by direct specification of cortical progenitors
Genetic studies of neocortical area patterning are limited, because mice deficient for candidate regulatory genes die before areas emerge and have other compli-cating issues. To define roles for the homeodomain transcription factor EMX2, we engineered nestin-Emx2 transgenic mice that overexpress Emx2 in cortical pro-genitors coincident with expression of endogenous Emx2 and survive postnatally. Cortical size, lamina-tion, thalamus, and thalamocortical pathfinding are normal in homozygous nestin-Emx2 mice. However, primary sensory and motor areas are disproportion-ately altered in size and shift rostrolaterally. Heterozygous transgenics have similar but smaller changes. Opposite changes are found in heterozygous Emx2 knockout mice. Fgf8 expression in the commissural plate of nestin-Emx2 mice is indistinguishable from wild-type, but Pax6 expression is downregulated in rostral cortical progenitors, suggesting that EMX2 re-pression of PAX6 specification of rostral identities contributes to reduced rostral areas. We conclude that EMX2 levels in cortical progenitors disproportionately specify sizes and positions of primary cortical areas
Isobaric multiplet yrast energies and isospin non-conserving forces
The isovector and isotensor energy differences between yrast states of
isobaric multiplets in the lower half of the region are quantitatively
reproduced in a shell model context. The isospin non-conserving nuclear
interactions are found to be at least as important as the Coulomb potential.
Their isovector and isotensor channels are dominated by J=2 and J=0 pairing
terms, respectively. The results are sensitive to the radii of the states,
whose evolution along the yrast band can be accurately followed.Comment: 4 pages, 4 figures. Superseeds second part of nucl-th/010404
The changing pattern of domestic cannabis cultivation in the UK and its impact on the cannabis market
With improvements in both technology and information cannabis is being increasingly grown indoors for domestic use, rather than being imported. This study examines 50 cannabis farms detected by an English police force, and examines the characteristics of the 61 suspects associated with them. The study highlights a UK pattern in domestic cultivation, that is moving away from large scale commercial cultivation, at times co-ordinated by South East Asian organised crime groups, to increased cultivation within residential premises by British citizens. Offenders range from those who have no prior criminal history to those who are serious and persistent offenders. The ramifications for law enforcement agencies and policy formers are discussed
Attractor Metadynamics in Adapting Neural Networks
Slow adaption processes, like synaptic and intrinsic plasticity, abound in
the brain and shape the landscape for the neural dynamics occurring on
substantially faster timescales. At any given time the network is characterized
by a set of internal parameters, which are adapting continuously, albeit
slowly. This set of parameters defines the number and the location of the
respective adiabatic attractors. The slow evolution of network parameters hence
induces an evolving attractor landscape, a process which we term attractor
metadynamics. We study the nature of the metadynamics of the attractor
landscape for several continuous-time autonomous model networks. We find both
first- and second-order changes in the location of adiabatic attractors and
argue that the study of the continuously evolving attractor landscape
constitutes a powerful tool for understanding the overall development of the
neural dynamics
Proposal for generalised Supersymmetry Les Houches Accord for see-saw models and PDG numbering scheme
The SUSY Les Houches Accord (SLHA) 2 extended the first SLHA to include
various generalisations of the Minimal Supersymmetric Standard Model (MSSM) as
well as its simplest next-to-minimal version. Here, we propose further
extensions to it, to include the most general and well-established see-saw
descriptions (types I/II/III, inverse, and linear) in both an effective and a
simple gauged extension of the MSSM framework. In addition, we generalise the
PDG numbering scheme to reflect the properties of the particles.Comment: 44 pages. Changed titl
The interaction of organic adsorbate vibrations with substrate lattice waves in methyl-Si(111)-(1 × 1)
The state of professional practice and policy in the English further education system: a view from below
This paper addresses a recurring theme regarding the UK’s Vocational Education and Training (VET) policy in which Further Education (FE) and training are primarily driven by employer demand. It explores the tensions associated with this process on the everyday working practices of FE practitioners and institutions and its impact on FE’s contribution to the wider processes of social and economic inclusion. At a time when Ofsted and employer-led organisations have cast doubt on the contribution of FE, we explore pedagogies of practice that are often unacknowledged by the current audit demands of officialdom. We argue that such practice provides a more enlightened view of the sector and the challenges it faces in addressing wider issues of social justice, employability and civic regeneration. At the same time, the irony of introducing laissez-faire initiatives designed to remove statutory qualifications for FE teachers ignores the progress made over the past decade in raising the professional profile and status of teachers and trainers in the sector. In addressing such issues, the paper explores the limits and possibilities of constructing professional and vocational knowledge from networks and communities of practice, schools, universities, business, employers and local authorities, in which FE already operates
Band termination in the N=Z Odd-Odd Nucleus 46V
High spin states in the odd-odd N=Z nucleus 46V have been identified. At low
spin, the T=1 isobaric analogue states of 46Ti are established up to I = 6+.
Other high spin states, including the band terminating state, are tentatively
assigned to the same T=1 band. The T=0 band built on the low-lying 3+ isomer is
observed up to the 1f7/2-shell termination at I=15. Both signatures of a
negative parity T=0 band are observed up to the terminating states at I = 16-
and I = 17-, respectively. The structure of this band is interpreted as a
particle-hole excitation from the 1d3/2 shell. Spherical shell model
calculations are found to be in excellent agreement with the experimental
results.Comment: 5 pages, 4 figure
Monitoring and measuring teaching excellence in higher education: from contrived competition to collective collaboration’
This chapter starts by interrogating the notion of teaching excellence. It then moves on to discussing some of the data sources currently used in Higher Education Institutions (HEIs) to monitor and measure the quality of teaching. What do these sources actually reveal about teaching excellence and how might we make better use of them? From large-scale national censuses like the National Student Survey (NSS) to institutional data sets such as teaching observations, the contribution that each source makes to our understanding of the quality of HE teaching is underexplored and contested. It is argued that there is a need for more transparent debate across HEIs and the sector as a whole about the benefits and limitations of such data as well as greater acknowledgement of the role of collaboration over competition. The chapter concludes that teaching excellence is a marketised misconception of the complex reality of the reciprocal relationship between teaching and learning. Contrary to policy rhetoric and far from encouraging an environment of collegial improvement, it introduces an unhelpful ethos of contrived competition into what is essentially an interdependent relationship underpinned by collective collaboration. It is by focusing attention on the latter where the real gains and insights are likely to be made
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