Absolute polarization angle calibration using polarized diffuse Galactic emission observed by BICEP

We present a method of cross-calibrating the polarization angle of a polarimeter using BICEP Galactic observations. \bicep\ was a ground based experiment using an array of 49 pairs of polarization sensitive bolometers observing from the geographic South Pole at 100 and 150 GHz. The BICEP polarimeter is calibrated to +/-0.01 in cross-polarization and less than +/-0.7 degrees in absolute polarization orientation. BICEP observed the temperature and polarization of the Galactic plane (R.A= 100 degrees ~ 270 degrees and Dec. = -67 degrees ~ -48 degrees). We show that the statistical error in the 100 GHz BICEP Galaxy map can constrain the polarization angle offset of WMAP Wband to 0.6 degrees +\- 1.4 degrees. The expected 1 sigma errors on the polarization angle cross-calibration for Planck or EPIC are 1.3 degrees and 0.3 degrees at 100 and 150 GHz, respectively. We also discuss the expected improvement of the BICEP Galactic field observations with forthcoming BICEP2 and Keck observations.Comment: 13 pages, 10 figures and 2 tables. To appear in Proceedings of SPIE Astronomical Telescopes and Instrumentation 201

Transmissibility of Atypical Scrapie in Ovine Transgenic Mice: Major Effects of Host Prion Protein Expression and Donor Prion Genotype

Atypical scrapie or Nor98 has been identified as a transmissible spongiform encephalopathy (TSE) that is clearly distinguishable from classical scrapie and BSE, notably regarding the biochemical features of the protease-resistant prion protein PrPres and the genetic factors involved in susceptibility to the disease. In this study we transmitted the disease from a series of 12 French atypical scrapie isolates in a transgenic mouse model (TgOvPrP4) overexpressing in the brain ∼0.25, 1.5 or 6× the levels of the PrPARQ ovine prion protein under the control of the neuron-specific enolase promoter. We used an approach based on serum PrPc measurements that appeared to reflect the different PrPc expression levels in the central nervous system. We found that transmission of atypical scrapie, much more than in classical scrapie or BSE, was strongly influenced by the PrPc expression levels of TgOvPrP4 inoculated mice. Whereas TgOvPrP4 mice overexpressing ∼6× the normal PrPc level died after a survival periods of 400 days, those with ∼1.5× the normal PrPc level died at around 700 days. The transmission of atypical scrapie in TgOvPrP4 mouse line was also strongly influenced by the prnp genotypes of the animal source of atypical scrapie. Isolates carrying the AF141RQ or AHQ alleles, associated with increased disease susceptibility in the natural host, showed a higher transmissibility in TgOvPrP4 mice. The biochemical analysis of PrPres in TgOvPrP4 mouse brains showed a fully conserved pattern, compared to that in the natural host, with three distinct PrPres products. Our results throw light on the transmission features of atypical scrapie and suggest that the risk of transmission is intrinsically lower than that of classical scrapie or BSE, especially in relation to the expression level of the prion protein

Eenzaamheid en zelfmanagementvaardigheden bij visueel beperkte ouderen

 0,001). De multivariate hiërarchische regressieanalyse toont aan dat de zelfmanagementvaardigheid self-efficacy, partner status en zelfwaardering samenhangen met eenzaamheid. Visus-gerelateerde variabelen, zoals de ernst en de duur van de visuele beperking, zijn niet geassocieerd met eenzaamheid. Discussie. Visueel beperkte ouderen zijn een risicogroep als het gaat om eenzaamheid. De samenhang met zelfmanagementvaardigheden biedt mogelijkheden aangezien deze vaardigheden aangeleerd kunnen worden en daarmee eenzaamheidsgevoelens bij visueel beperkte ouderen kunnen verminderen. Een aangepaste versie van dit paper is verschenen in Journal of Aging and Health, doi:10.1177/0898264311399758

CMB-S4: Forecasting Constraints on Primordial Gravitational Waves

CMB-S4---the next-generation ground-based cosmic microwave background (CMB) experiment---is set to significantly advance the sensitivity of CMB measurements and enhance our understanding of the origin and evolution of the Universe, from the highest energies at the dawn of time through the growth of structure to the present day. Among the science cases pursued with CMB-S4, the quest for detecting primordial gravitational waves is a central driver of the experimental design. This work details the development of a forecasting framework that includes a power-spectrum-based semi-analytic projection tool, targeted explicitly towards optimizing constraints on the tensor-to-scalar ratio, $r$, in the presence of Galactic foregrounds and gravitational lensing of the CMB. This framework is unique in its direct use of information from the achieved performance of current Stage 2--3 CMB experiments to robustly forecast the science reach of upcoming CMB-polarization endeavors. The methodology allows for rapid iteration over experimental configurations and offers a flexible way to optimize the design of future experiments given a desired scientific goal. To form a closed-loop process, we couple this semi-analytic tool with map-based validation studies, which allow for the injection of additional complexity and verification of our forecasts with several independent analysis methods. We document multiple rounds of forecasts for CMB-S4 using this process and the resulting establishment of the current reference design of the primordial gravitational-wave component of the Stage-4 experiment, optimized to achieve our science goals of detecting primordial gravitational waves for $r > 0.003$ at greater than $5\sigma$, or, in the absence of a detection, of reaching an upper limit of $r < 0.001$ at $95\%$ CL.Comment: 24 pages, 8 figures, 9 tables, submitted to ApJ. arXiv admin note: text overlap with arXiv:1907.0447

CMB-S4

We describe the stage 4 cosmic microwave background ground-based experiment CMB-S4

CMB-S4: Forecasting Constraints on Primordial Gravitational Waves

Abstract: CMB-S4—the next-generation ground-based cosmic microwave background (CMB) experiment—is set to significantly advance the sensitivity of CMB measurements and enhance our understanding of the origin and evolution of the universe. Among the science cases pursued with CMB-S4, the quest for detecting primordial gravitational waves is a central driver of the experimental design. This work details the development of a forecasting framework that includes a power-spectrum-based semianalytic projection tool, targeted explicitly toward optimizing constraints on the tensor-to-scalar ratio, r, in the presence of Galactic foregrounds and gravitational lensing of the CMB. This framework is unique in its direct use of information from the achieved performance of current Stage 2–3 CMB experiments to robustly forecast the science reach of upcoming CMB-polarization endeavors. The methodology allows for rapid iteration over experimental configurations and offers a flexible way to optimize the design of future experiments, given a desired scientific goal. To form a closed-loop process, we couple this semianalytic tool with map-based validation studies, which allow for the injection of additional complexity and verification of our forecasts with several independent analysis methods. We document multiple rounds of forecasts for CMB-S4 using this process and the resulting establishment of the current reference design of the primordial gravitational-wave component of the Stage-4 experiment, optimized to achieve our science goals of detecting primordial gravitational waves for r > 0.003 at greater than 5σ, or in the absence of a detection, of reaching an upper limit of r < 0.001 at 95% CL

Ligand for translocator protein increases hippocampal expression of glial Abeta scavenger receptors and reduces Abeta in male mice & rats

BackgroundTranslocator protein (TSPO) is a multi-functional mitochondrial transmembrane protein primarily localised in steroid-producing tissues, including the brain. TSPO ligands elicit pleiotropic neuroprotective and cognitive benefits, mechanistically linked to the regulation of steroid synthesis and gliosis. Our recent findings in 3xTgAD mice demonstrate that TSPO ligands not only reduce development of Abeta neuropathology in young mice, but also reverse pathology in aged mice, suggesting TSPO ligands may promote Abeta clearance. Since glia-mediated Abeta phagocytosis and degradation is an important mechanism of brain Abeta clearance, we investigated the effect of a TSPO ligand on markers of glial function and expression of glial Abeta-scavenging receptors.MethodsEffects of the TSPO ligands, Ro5-4864 and PK-11195, on brain Abeta levels in mice were assessed. The dose dependent effects of the most effective ligand, Ro5-4864, were compared with the anti-amyloidogenic neuroactive steroid, testosterone, in rats. Abeta levels were assessed by ELISA and hippocampal mRNA expression of markers of glial function (glial fibrillary acidic protein; GFAP; major histopatability complex II; MHC II; interleukin-1beta; IL-1beta; tumor necrosis factor-alpha, TNF-alpha) and glial Abeta scavenger receptors (scavenger receptor-A1, SR-A1; scavenger receptor-B1, SR-B1) were assessed by PCR. ResultsRo5-4864 reduced Abeta-40 more effectively than PK-11195, while combined Ro5-4864 + PK-11195 had an additive anti-amyloidogenic effect. In rats, Ro5-4864 dose-dependently reduced Abeta-40 levels and was equally effective as testosterone. In Ro5-4864 treated rats, reduced Abeta levels were associated with elevated expression of GFAP, MHC-II, and glial Abeta scavenger receptors; although levels of the pro-inflammatory cytokines, IL-1beta and TNFalpha, were unaltered. In contrast, testosterone had an anti-inflammatory effect, reducing levels of GFAP, MHC-II, IL-1beta and TNF-alpha, without altering expression of glial scavenger receptors.ConclusionsThe TSPO ligand Ro5-4864 may promote trophic glial activity, including increasing Abeta phagocytic capacity in the absence of detrimental proinflammatory cytokine production. Since glial TSPO is upregulated in the most severely affected regions of the Alzheimer`s brain, TSPO ligands may selectively target regions most affected by the disease. Many new generation, safe TSPO ligands have been developed for in vivo imaging in humans, however our findings suggest these ligands may also have a therapeutic potential for the treatment of Alzheimer`s.The Alzheimer\u27s Association International Conference 201