National level promotion of physical activity: results from England's ACTIVE for LIFE campaign.

STUDY OBJECTIVE: To assess the impact of a national campaign on awareness of the campaign, change in knowledge of physical activity recommendations and self reported physical activity. DESIGN: three year prospective longitudinal survey using a multi-stage, cluster random probability design to select participants. SETTING: England. PARTICIPANTS: A nationally representative sample of 3189 adults aged 16-74 years. MAIN OUTCOME MEASURES: Awareness of the advertising element of the campaign, changes in knowledge of physical activity recommendations for health and self reported physical activity. RESULTS: 38% of participants were aware of the main advertising images, assessed six to eight months after the main television advertisement. The proportion of participants knowledgeable about moderate physical activity recommendations increased by 3.0% (95% CI: 1.4%, 4.5%) between waves 1 and 2 and 3.7% (95% CI: 2.1%, 5.3%) between waves 1 and 3. The change in proportion of active people between baseline and waves 1 and 2 was -0.02 (95% CI: -2.0 to +1.7) and between waves 1 and 3 was -9.8 (-7.9 to -11.7). CONCLUSION: The proportion of participants who were knowledgeable about the new recommendations, increased significantly after the campaign. There was however, no significant difference in knowledge by awareness of the main campaign advertisement. There is no evidence that ACTIVE for LIFE improved physical activity, either overall or in any subgroup

Spin Gaps in a Frustrated Heisenberg model for CaV4_4O9_9

I report results of a density matrix renormalization group (DMRG) study of a model for the two dimensional spin-gapped system CaV$_4$O$_9$. This study represents the first time that DMRG has been used to study a two dimensional system on large lattices, in this case as large as $24\times 11$, allowing extrapolation to the thermodynamic limit. I present a substantial improvement to the DMRG algorithms which makes these calculations feasible.Comment: 10 pages, with 4 Postscript figure

Efficacy and effectiveness of dihydroartemisinin-piperaquine versus artesunate-mefloquine in falciparum malaria: an open-label randomised comparison.

BACKGROUND: Artemisinin-based combinations are judged the best treatments for multidrug-resistant Plasmodium falciparum malaria. Artesunate-mefloquine is widely recommended in southeast Asia, but its high cost and tolerability profile remain obstacles to widespread deployment. To assess whether dihydroartemisinin-piperaquine is a suitable alternative to artesunate-mefloquine, we compared the safety, tolerability, efficacy, and effectiveness of the two regimens for the treatment of uncomplicated falciparum in western Myanmar (Burma). METHODS: We did an open randomised comparison of 3-day regimens of artesunate-mefloquine (12/25 mg/kg) versus dihydroartemisinin-piperaquine (6.3/50 mg/kg) for the treatment of children aged 1 year or older and in adults with uncomplicated falciparum malaria in Rakhine State, western Myanmar. Within each group, patients were randomly assigned supervised or non-supervised treatment. The primary endpoint was the PCR-confirmed parasitological failure rate by day 42. Failure rates at day 42 were estimated by Kaplan-Meier survival analysis. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN27914471. FINDINGS: Of 652 patients enrolled, 327 were assigned dihydroartemisinin-piperaquine (156 supervised and 171 not supervised), and 325 artesunate-mefloquine (162 and 163, respectively). 16 patients were lost to follow-up, and one patient died 22 days after receiving dihydroartemisinin-piperaquine. Recrudescent parasitaemias were confirmed in only two patients; the day 42 failure rate was 0.6% (95% CI 0.2-2.5) for dihydroartemisinin-piperaquine and 0 (0-1.2) for artesunate-mefloquine. Whole-blood piperaquine concentrations at day 7 were similar for patients with observed and non-observed dihydroartemisinin-piperaquine treatment. Gametocytaemia developed more frequently in patients who had received dihydroartemisinin-piperaquine than in those on artesunate-mefloquine: day 7, 18 (10%) of 188 versus five (2%) of 218; relative risk 4.2 (1.6-11.0) p=0.011. INTERPRETATION: Dihydroartemisinin-piperaquine is a highly efficacious and inexpensive treatment of multidrug-resistant falciparum malaria and is well tolerated by all age groups. The effectiveness of the unsupervised treatment, as in the usual context of use, equalled its supervised efficacy, indicating good adherence without supervision. Dihydroartemisinin-piperaquine is a good alternative to artesunate-mefloquine

Unusually Large Fluctuations in the Statistics of Galaxy Formation at High Redshift

We show that various milestones of high-redshift galaxy formation, such as the formation of the first stars or the complete reionization of the intergalactic medium, occurred at different times in different regions of the universe. The predicted spread in redshift, caused by large-scale fluctuations in the number density of galaxies, is at least an order of magnitude larger than previous expectations that argued for a sharp end to reionization. This cosmic scatter in the abundance of galaxies introduces new features that affect the nature of reionization and the expectations for future probes of reionization, and may help explain the present properties of dwarf galaxies in different environments. The predictions can be tested by future numerical simulations and may be verified by upcoming observations. Current simulations, limited to relatively small volumes and periodic boundary conditions, largely omit cosmic scatter and its consequences. In particular, they artificially produce a sudden end to reionization, and they underestimate the number of galaxies by up to an order of magnitude at redshift 20.Comment: 8 ApJ pages, 4 figures, ApJ. Minor changes in revised version. Originally first submitted for publication on Aug. 29, 200

Phase diagram of the half-filled Hubbard chain with next-nearest-neighbor hopping

We investigate the ground-state phase diagram of the half-filled one-dimensional Hubbard model with next-nearest-neighbor hopping using the Density-Matrix Renormalization Group technique as well as an unrestricted Hartree-Fock approximation. We find commensurate and incommensurate disordered magnetic insulating phases and a spin-gapped metallic phase in addition to the one-dimensional Heisenberg phase. At large on-site Coulomb repulsion $U$, we make contact with the phase diagram of the frustrated Heisenberg chain, which has spin-gapped phases for sufficiently large frustration. For weak $U$, sufficiently large next-nearest-neighbor hopping $t_2$ leads to a band structure with four Fermi points rather than two, producing a spin-gapped metallic phase. As $U$ is increased in this regime, the system undergoes a Mott-Hubbard transition to a frustrated antiferromagnetic insulator

Effects of nanoscale spatial inhomogeneity in strongly correlated systems

We calculate ground-state energies and density distributions of Hubbard superlattices characterized by periodic modulations of the on-site interaction and the on-site potential. Both density-matrix renormalization group and density-functional methods are employed and compared. We find that small variations in the on-site potential $v_i$ can simulate, cancel, or even overcompensate effects due to much larger variations in the on-site interaction $U_i$. Our findings highlight the importance of nanoscale spatial inhomogeneity in strongly correlated systems, and call for reexamination of model calculations assuming spatial homogeneity.Comment: 5 pages, 1 table, 4 figures, to appear in PR

Application of the Density Matrix Renormalization Group Method to a Non-Equilibrium Problem

We apply the density matrix renormalization group (DMRG) method to a non-equilibrium problem: the asymmetric exclusion process in one dimension. We study the stationary state of the process to calculate the particle density profile (one-point function). We show that, even with a small number of retained bases, the DMRG calculation is in excellent agreement with the exact solution obtained by the matrix-product-ansatz approach.Comment: 8 pages, LaTeX (using jpsj.sty), 4 non-embedded figures, submitted to J. Phys. Soc. Jp

Manipulating biphotonic qutrits

Quantum information carriers with higher dimension than the canonical qubit offer significant advantages. However, manipulating such systems is extremely difficult. We show how measurement induced non-linearities can be employed to dramatically extend the range of possible transforms on biphotonic qutrits; the three level quantum systems formed by the polarisation of two photons in the same spatio-temporal mode. We fully characterise the biphoton-photon entanglement that underpins our technique, thereby realising the first instance of qubit-qutrit entanglement. We discuss an extension of our technique to generate qutrit-qutrit entanglement and to manipulate any bosonic encoding of quantum information.Comment: 4 pages, 4 figure