Quantum control of electromagnetically induced transparency dispersion via atomic tunneling in a double-well Bose-Einstein condensate

Electromagnetically induced transparency (EIT) is an important tool for controlling light propagation and nonlinear wave mixing in atomic gases with potential applications ranging from quantum computing to table top tests of general relativity. Here we consider EIT in an atomic Bose-Einstein condensate (BEC) trapped in a double-well potential. A weak probe laser propagates through one of the wells and interacts with atoms in a three-level Lambda configuration. The well through which the probe propagates is dressed by a strong control laser with Rabi frequency Omega(mu), as in standard EIT systems. Tunneling between the wells at the frequency g provides a coherent coupling between identical electronic states in the two wells, which leads to the formation of interwell dressed states. The macroscopic interwell coherence of the BEC wave function results in the formation of two ultranarrow absorption resonances for the probe field that are inside of the ordinary EIT transparency window. We show that these new resonances can be interpreted in terms of the interwell dressed states and the formation of a type of dark state involving the control laser and the interwell tunneling. To either side of these ultranarrow resonances there is normal dispersion with very large slope controlled by g. We discuss prospects for observing these ultranarrow resonances and the corresponding regions of high dispersion experimentally.

Blocking semiovals of Type (1,M+1,N+1)

We consider the existence of blocking semiovals in finite projective planes which have intersection sizes 1, m+1 or n+1 with the lines of the plane for $1 \leq m < n$. For those prime powers $q \leq 1024$, in almost all cases, we are able to show that, apart from a trivial example, no such blocking semioval exists in a projective plane of order q. We are also able to prove, for general q, that if q2+q+1 is a prime or three times a prime, then only the same trivial example can exist in a projective plane of order q.

Deployment of DGT units in marine waters to assess the environmental risk from a deep sea tailings outfall

Measurements of total, filterable and DGT-labile concentrations of nine metals (Al, Cd, Cr, Cu, Fe, Pb, Mn, Ni and Zn) have been made at five sites up to 4.2km from a deep sea tailings outfall operated by Lihir Gold Ltd. at Lihir Island, Papua New Guinea. At each site, pairs of DGT units (one containing a 0.4mm and the other a 0.8mm diffusive gel layer) were deployed at three depths (50–70; 105–130; 135–155m) for 4–7 days. Comparison of predicted water column DGT-labile metal concentrations in field deployments showed the 0.8mm DGT units were relatively enriched in metals, with the effect being greatest closer to the outfall for Pb and Mn and least for Fe, Cr, Ni and Zn. The most likely explanation for this is that in addition to simple ion diffusion, kinetic factors associated with ageing or desorption processes govern release of metals from iron and aluminium oxyhydroxide colloids which diffuse through the gels. The thicker gels have a longer residence time over which metals can be released for adsorption. This model explains why enrichment is most pronounced near the outfall; more distant sites have lower colloid concentrations because of the longer time for coagulation to increase particle sizes to the extent they cannot enter the gels. Total and filterable metal (FM) concentrations were frequently below the limits of detection (LOD) achievable by conventional ICP-AES (1–52gL⁻¹) and this limited their usefulness for assessing environmental risk and for metal speciation determination. Because of its pre-concentration step DGT gave metal concentrations above their LODs and these decreased exponentially with distance from the outfall. Concentrations of DGT–labile metal fell below Australian water quality guidelines for protection of 99% of marine organisms within 0.13km of the outfall for Cd, Cr and Ni and below that for protection of 95% of marine organisms within 0.4, 0.7 and 3.6km for lead, zinc and copper, respectively.

Monitoring the safe use of Clozapine : a consensus view from Victoria, Australia

Clozapine is an important antipsychotic agent that has a unique profile of clinical benefits, but that has also been associated with several serious and potentially life-threatening safety concerns. In order to minimise the impact of haematological adverse events, health professionals treating patients with clozapine are currently required to register their patients on a centrally administered data network and to conform to strict protocols. The consensus statement documented in this article extends existing protocols by recommending monitoring of patients treated with clozapine for additional adverse effects during treatment. This consensus statement reflects the current practice at five major public psychiatric hospitals in Victoria, Australia, for the monitoring and management of clozapine-related adverse events, and has been implemented at these sites because of emerging safety concerns associating clozapine with cardiovascular and metabolic adverse effects.

The role of psychotherapy in bipolar disorder

• Adjunctive psychosocial interventions for bipolar disorder target many of the issues that are not addressed by medication alone, including non-adherence, efficacy–effectiveness gap and functionality.

• Psychosocial interventions have been found to reduce relapse, particularly for the depressive pole, and improve functionality.

• Approaches such as psychoeducation, cognitive behaviour therapy, interpersonal and social rhythm therapy, and family therapy have shown benefits as adjunctive treatments.

• Each of the various psychosocial interventions has a unique emphasis, but they share common elements. These include: providing information and education; developing a personal understanding of the illness, such as triggers and early warning signs; having prepared strategies in place for early intervention, should symptoms of illness develop; and promoting a collaborative approach.

• Evidence to date supports the use of adjunctive psychosocial interventions in the management of bipolar disorder.

Children's literature in a global age : transnational and local identities

This essay explores the concept of transnationalism, defi ning this term in relation both to the lived experience of transnational subjects, and to transnational texts for children. It argues that rhetorics of globalization have over-emphasized the impact and signifi cance of global cultural and economic fl ows, although the production of children’s books is to some extent shaped by the internationalization of publishing houses and markets. The concept of transnationalism provides a way of thinking about how children’s texts address and are informed by diverse, complex infl uences, sometimes from a variety of cultures and languages. Transnationalism is not a new phenomenon but is visible in colonial texts which are shaped both by the particular, local ideologies of colonial nations, and also by the common concerns and interests of such nations. The essay draws on two contemporary texts to illustrate the workings of transnationalism: the fi lm Howl’s Moving Castle, and Shaun Tan’s picture book The Arrival. It concludes by considering the concept of transnational literacy as a way of approaching scholarship and teaching in children’s literature.