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The ghost-free massive spin-2 field of bimetric theory turns out to be an amusing dark matter candidate. I review the theoretical foundations of bimetric theory, and outline the qualities and phenomenology of heavy spin-2 dark matter. [ABSTRACT FROM AUTHOR]

In this paper, the strongest limits, obtained from rotation measures on cosmological magnetic fields, are presented. [ABSTRACT FROM AUTHOR]

Arp, C.D., B.M. Jones, M. Whitman, A. Larsen, and F.E. Urban, 2010. Lake Temperature and Ice Cover Regimes in the Alaskan Subarctic and Arctic: Integrated Monitoring, Remote Sensing, and Modeling. Journal of the American Water Resources Association (JAWRA) 46(4): 777-791. DOI: 10.1111/j.1752-1688.2010.00451.x Lake surface regimes are fundamental attributes of lake ecosystems and their interaction with the land and atmosphere. High latitudes may be particularly sensitive to climate change, however, adequate baselines for these lakes are often lacking. In this study, we couple monitoring, remote sensing, and modeling techniques to generate baseline datasets of lake surface temperature and ice cover in the Alaskan Subarctic and Arctic. No detectable trends were observed during this study period, but a number of interesting patterns were noted among lakes and between regions. The largest Arctic lake was relatively unresponsive to air temperature, while the largest Subarctic lake was very responsive likely because it is fed by glacial runoff. Mean late summer water temperatures were higher than air temperatures with differences ranging from 1.7 to 5.4°C in Subarctic lakes and from 2.4 to 3.2°C in Arctic lakes. The warmest mean summer water temperature in both regions was in 2004, with the exception of Subarctic glacially fed lake that was highest in 2005. Ice-out timing had high coherence within regions and years, typically occurring in late May in Subarctic and in early-July in Arctic lakes. Ice-on timing was more dependent on lake size and depth, often varying among lakes within a region. Such analyses provide an important baseline of lake surface regimes at a time when there is increasing interest in high-latitude water ecosystems and resources during an uncertain climate future. [ABSTRACT FROM AUTHOR]

Purpose: To determine the validity of scanning laser ophthalmoscopy in the retromode (RM-SLO) versus other imaging modalities in the diagnosis of diabetic macular oedema (DME)., Methods: Two hundred and sixty-three eyes were examined. Inclusion criteria were any stage of untreated or treated diabetic retinopathy and four imaging modalities of the macula carried out on the same day: time domain optical coherence tomography (OCT), fundus autofluorescence (FAF), RM-SLO and fluorescein angiography (FA). Two masked retinal specialists independently graded all images. Agreement between RM-SLO and OCT, FA and FAF in evaluating the presence and patterns of DME was evaluated by kappa statistics, sensitivity, specificity, observed proportional agreement, and proportional agreement in positive and negative cases., Results: The agreement in evaluating the presence/absence of DME between RM-SLO and OCT, FA and FAF was good: κ = 0.73 (confidence interval; CI, 0.64-0.83), κ = 0.71 (CI, 0.61-0.81) and κ = 0.73 (CI, 0.63-0.83), respectively. The agreement in evaluating cystoid pattern of DME was almost perfect between RM-SLO and OCT, RM-SLO and FA, κ > 0.8; and good between RM-SLO and FAF, κ > 0.7. The agreement in evaluating the presence/absence of subfoveal neuroretinal was almost perfect between RM-SLO and OCT (κ = 0.83; 95% CI, 0.70-0.96). Subfoveal neuroretinal detachment did not show any specific pattern on FA or FAF. Sensitivity and specificity of RM-SLO in evaluating DME was 97.7% and 71.9% versus OCT, 97.4% and 68.1% versus FA and 96.1% and 73.3% versus FAF. Retinal thickness of 233 μm represented the cut-off value to define DME by RM-SLO., Conclusions: The combined use of non-invasive imaging techniques can improve the diagnostic interpretation of different aspects of DME., (© 2012 The Authors. Acta Ophthalmologica © 2012 Acta Ophthalmologica Scandinavica Foundation.)