Parameter estimation biases due to contributions from the Rees-Sciama effect to the integrated Sachs-Wolfe spectrum

The subject of this paper is an investigation of the non-linear contributions to the spectrum of the integrated Sachs-Wolfe (iSW) effect. We derive the corrections to the iSW autospectrum and the iSW-tracer cross-spectrum consistently to third order in perturbation theory and analyse the cumulative signal-to-noise ratio for a cross-correlation between the Planck and Euclid data sets as a function of multipole order. We quantify the parameter sensitivity and the statistical error bounds on the cosmological parameters Ωm, σ8, h, ns and w from the linear iSW effect and the systematical parameter estimation bias due to the non-linear corrections in a Fisher formalism, analysing the error budget in its dependence on multipole order. Our results include the following: (i) the spectrum of the non-linear iSW effect can be measured with 0.8σ statistical significance, (ii) non-linear corrections dominate the spectrum starting from ℓ≃ 102, (iii) an anticorrelation of the CMB temperature with tracer density on high multipoles in the non-linear regime, (iv) a much weaker dependence of the non-linear effect on the dark energy model compared to the linear iSW effect and (v) parameter estimation biases amount to less than 0.1σ and weaker than other systematic

On the validity of the Born approximation for weak cosmic flexions

Weak lensing calculations are often made under the assumption of the Born approximation, where the ray path is approximated as a straight radial line. In addition, lens-lens couplings where there are several deflections along the light ray are often neglected. We examine the effect of dropping the Born approximation and taking lens-lens couplings into account, for weak lensing effects up to second order (cosmic flexion), by making a perturbative expansion in the light path. We present a diagrammatic representation of the resulting corrections to the lensing effects. The flexion signal, which measures the derivative of the density field, acquires correction terms proportional to the squared gravitational shear; we also find that by dropping the Born approximation, two further degrees of freedom of the lensing distortion can be excited (the twist components), in addition to the four standard flexion components. We derive angular power spectra of the flexion and twist, with and without the Born approximation and lens-lens couplings and confirm that the Born approximation is an excellent approximation for weak cosmic flexions, but may fail in the strong lensing regim

A Role for Fucose α(1−2) Galactose Carbohydrates in Neuronal Growth

We report a fucose α(1−2) galactose-mediated pathway for the modulation of neuronal growth and morphology. Our studies provide strong evidence for the presence of Fucα(1−2)Gal glycoproteins and lectin receptors in hippocampal neurons. Additionally, we show that manipulation of Fucα(1−2)Gal-associated proteins using small-molecule and lectin probes induces dramatic changes in neuronal morphology. These findings may provide a novel pathway to stimulate neuronal growth and regeneration

On the validity of the Born approximation for weak cosmic flexions

Weak lensing calculations are often made under the assumption of the Born approximation, where the ray path is approximated as a straight radial line. In addition, lens-lens couplings where there are several deflections along the light ray are often neglected. We examine the effect of dropping the Born approximation and taking lens-lens couplings into account, for weak lensing effects up to second order (cosmic flexion), by making a perturbative expansion in the light path. We present a diagrammatic representation of the resulting corrections to the lensing effects. The flexion signal, which measures the derivative of the density field, acquires correction terms proportional to the squared gravitational shear; we also find that by dropping the Born approximation, two further degrees of freedom of the lensing distortion can be excited (the twist components), in addition to the four standard flexion components. We derive angular power spectra of the flexion and twist, with and without the Born-approximation and lens-lens couplings and confirm that the Born approximation is an excellent approximation for weak cosmic flexions, except at very small scales.Comment: 12 pages, 5 figures, submitted to MNRA

A Solvent-Free Method for Isotopically or Radioactively Labeling Cyclodextrins and Cyclodextrin-Containing Polymers

A method for installing a distinguishable label onto cyclodextrins or cyclodextrin-containing polymers is reported. Cyclodextrins (CD) and cyclodextrin-containing polymers are exposed to labeled (^2H or ^(14)C) ethylene oxide (EO) vapor and the alcohol groups on the CD ring open the EO to give ether-linked labeled methylenes and a terminal alcohol. This method provides for the incorporation of an easily tracked and quantified label without the use of solvents or purification steps. The method can be generalized for use with materials that contain nucleophiles other than alcohols, e.g., amines

A Solvent-Free Method for Isotopically or Radioactively Labeling Cyclodextrins and Cyclodextrin-Containing Polymers

A method for installing a distinguishable label onto cyclodextrins or cyclodextrin-containing polymers is reported. Cyclodextrins (CD) and cyclodextrin-containing polymers are exposed to labeled (^2H or ^(14)C) ethylene oxide (EO) vapor and the alcohol groups on the CD ring open the EO to give ether-linked labeled methylenes and a terminal alcohol. This method provides for the incorporation of an easily tracked and quantified label without the use of solvents or purification steps. The method can be generalized for use with materials that contain nucleophiles other than alcohols, e.g., amines

Interferon-γ induced expression of MHC antigens facilitates identification of donor cells in chimeric transplant recipients

After whole organ transplantation, donor bone marrow-derived cells migrate out of the graft into the recipient, leading to establishment of chimerism, which is the first step towards the subsequent induction of donor-specific tolerance. In routine immunohistochemical staining, monoclonal antibodies specific for heterotopic MHC alleles are used to identify donor and recipient cells. However, it is difficult to detect these cells using this technique in long-term allograft recipients who have a persistently low donor cell population (microchimerism). Because Interferon-gamma (IFN-γ) is known to induce expression of MHC class I and class II cell surface molecules, we used this cytokine 12-48 h before sacrifice, to facilitate the identification of donor and recipient cells in the tissues of animals transplanted with either liver (B10 → C3H) or bone marrow (LEW → BN). In long-term allograft recipients, the use of IFN-γ for as briefly as 12 h prior to sacrifice, results in marked upregulation of class I and class II antigens, leading to easy identification of ubiquitously distributed low numbers of donor cells. © 1994