Three-body correlations in a two-dimensional SU(3) Fermi gas

We consider a three-component Fermi gas that has SU(3) symmetry and is confined to two dimensions (2D). For realistic cold atomic gas experiments, we show that the phase diagram of the quasi-2D system can be characterized using two 2D scattering parameters: the scattering length and the effective range. Unlike the case in 3D, we argue that three-body bound states (trimers) in the quasi-2D system can be stable against three-body losses. Using a low-density expansion coupled with a variational approach, we investigate the fate of such trimers in the many-body system as the attractive interactions are decreased (or, conversely, as the density of particles is increased). We find that remnants of trimers can persist in the form of strong three-body correlations in the weak-coupling (high-density) limit.Comment: 13 pages, 4 figure

The brutal logic of the political marketplace

In the first of a series of commentaries on the JSRP’s emerging ideas, Tom Kirk reports on Alex de Waal’s recent book launch and explores the use of grand political ordering frameworks for interpreting conflict affected regions

Between pragmatism and structural change: future security and justice programming in difficult places

Tom Kirk explores a recent ODI report on the future of justice and security programming, and comments upon what the JSRP’s research findings from the world’s most difficult places may mean for ongoing debates

How a ‘public authority’ lens can help us understand NGOs and INGOs

A ‘public authorities’ lens is useful for understanding how governance works in conflict-affected places. But how can this lens inform the way we think about the NGOs and INGOs that operate in them? Tom Kirk explains why the question is crucial to exploring the kinds of development these organisations are promoting

On the ultimate precision of meson mixing observables

Meson mixing is considered to be an ideal candidate for new physics searches. Current experimental precision has greatly increased over the recent years, excelling in several cases the theoretical precision. A possible limit in the theoretical accuracy could be a hypothetical breakdown of quark-hadron duality. We propose a simple model for duality violations and give stringent bounds on such effects for mixing observables, indicating regions, where future measurements of $\Delta \Gamma_d$, $a_{sl}^d$ and $a_{sl}^s$ would be clear signals of new physics. Finally, we turn our attention to the charm sector, and reveal that already a modest duality violation of about $20 \%$ could explain the huge difference between HQE predictions for D-mixing and experimental data.Comment: 37 pages, 9 figures. v2 (very belated) update to journal version (plus extended appendices

Targeted disruption of the murine int-1 proto-oncogene resulting in severe abnormalities in midbrain and cerebellar development.

Journal ArticleThe int-1 proto-oncogene was first identified as a gene activated in virally induced mouse mammary tumours. Expression studies, however, suggest that the normal function of this gene may be in spermatogenesis and in the development of the central nervous system. Genes sharing sequence similarity with int-1 have been found throughout the animal kingdom. For example, int-1 has 54% amino-acid identity to the Drosophila segment polarity gene wingless (wg). Both the int-1 and wg gene products seem to be secreted proteins, presumably involved in cell-cell signalling. We have now explored the function of int-1 in the mouse by disrupting one of the two int-1 alleles in mouse embryo-derived stem cells using positive-negative selection. This cell line was used to generate a chimaeric mouse that transmitted the mutant allele to its progeny. Mice heterozygous for the int-1 null mutation are normal and fertile, whereas mice homozygous for the mutation may exhibit a range of phenotypes from death before birth to survival with severe ataxia. The latter pathology in mice and humans is often associated with defects in the cerebellum. Examination of int-1-/int-1- mice at several stages of embryogenesis revealed severe abnormalities in the development of the mesencephalon and metencephalon indicating a prominent role for the int-1 protein is in the induction of the mesencephalon and cerebellum

Introduction of homologous DNA sequences into mammalian cells induces mutations in the cognate gene.

Journal ArticleInjection of homologous DNA sequences into nuclei of cultured mammalian cells induces mutations in the cognate chromosomal gene. It appears that these mutations result from incorrect repair of a heteroduplex formed between the introduced and the chromosomal sequence. This phenomenon is termed 'heteroduplex induced mutagenesis'. The high frequency of these events suggests that this method may prove useful for introducing mutations into specific mammalian genes

Letter from Thomas J. Kirk

Letter concerning programs of domestic science and art in California

Critical Issues for Administrators of Specialized Schools

The current call for accountability in education increases the need for an understanding of best practices for administrators of specialized schools that serve students with special needs, including residential and day treatment programs. The literature revealed issues in curriculum planning and resource allocation to meet the complex and interrelated needs of students in specialized schools, and in effective program design for students with specific low incidence disabilities. No literature could be identified that addressed the challenges of administering specialized schools that integrate educational, therapeutic, and transitional and vocational programs in one setting. A survey of administrators of specialized schools in one Northern California county was conducted to identify best practices for decision making and resource allocation in a time of dwindling local, state and national resources. Four administrators working in specialized programs in Northern California were interviewed using a questionnaire. Findings indicated that administrators of specialized schools make decisions about staffing, training and curriculum based on their students’ needs for integrated services in order to support development across three domains: 1) academic, 2) therapeutic, and 3) vocational, transitional and independent living skill training. Administrator responses emphasized communication and collaboration between all domains as essential for student success. Findings further indicated that administrators agreed that students do best when teachers receive support for their emotional and social needs as well as their curriculum and instructional planning needs