Reference Profile Correlation Reveals Estrogen-like Trancriptional Activity of Curcumin

Background: Several secondary metabolites from herbal nutrient products act as weak estrogens (phytoestrogens), competing with endogenous estrogen for binding to the estrogen receptors and inhibiting steroid converting enzymes. However, it is still unclear whether these compounds elicit estrogen dependent transcription of genes at physiological concentrations. Methods: We compare the effects of physiological concentrations (100 nM) of the two phytoestrogens Enterolactone and Quercetin and the suspected phytoestrogen Curcumin on gene expression in the breast cancer cell line MCF7 with the effects elicited by 17-beta-estradiol (E2). Results: All three phytocompounds have weak effects on gene transcription; most of the E2 genes respond to the phytoestrogens in the same direction though to a much lesser extent and in the order Curcumin > Quercetin > Enterolactone. Gene regulation induced by these compounds was low for genes strongly induced by E2 and similar to the latter for genes only weakly regulated by the classic estrogen. Of interest with regard to the treatment of menopausal symptoms, the survival factor Birc5/survivin and the oncogene MYBL1 are strongly induced by E2 but only marginally by phytoestrogens. Conclusion: This approach demonstrates estrogenic effects of putative phytoestrogens at physiological concentrations and shows, for the first time, estrogenic effects of Curcumin. Copyright (C) 2010 S. Karger AG, Base

The Structure of Isothermal, Self-gravitating Gas Spheres for Softened Gravity

A theory for the structure of isothermal, self-gravitating gas spheres in pressure equilibrium in a softened gravitational field is developed. The one parameter spline softening proposed by Hernquist & Katz (1989) is used. We show that the addition of this extra scale parameter implies that the set of equilibrium solutions constitute a one-parameter family, rather than the one and only one isothermal sphere solution for Newtonian gravity. We demonstrate the perhaps somewhat surprising result that for any finite choice of softening length and temperature, it is possible to deposit an arbitrarily large mass of gas in pressure equilibrium and with a non-singular density distribution inside of r_0 for any r_0 > 0. The theoretical predictions of our models are compared with the properties of the small, massive, quasi-isothermal gas clumps which typically form in numerical Tree-SPH simulations of 'passive' galaxy formation of Milky Way sized galaxies. We find reasonable agreement despite the neglect of rotational support in the models. We comment on whether the hydrodynamical resolution in our numerical simulation of galaxy formation is sufficient, and finally we conclude that one should be cautious, when comparing results of numerical simulations involving gravitational softening and hydrodynamical smoothing, with reality.Comment: 22 pages Latex + 12 figure

Critical Casimir effect in films for generic non-symmetry-breaking boundary conditions

Systems described by an O(n) symmetrical $\phi^4$ Hamiltonian are considered in a $d$-dimensional film geometry at their bulk critical points. A detailed renormalization-group (RG) study of the critical Casimir forces induced between the film's boundary planes by thermal fluctuations is presented for the case where the O(n) symmetry remains unbroken by the surfaces. The boundary planes are assumed to cause short-ranged disturbances of the interactions that can be modelled by standard surface contributions $\propto \bm{\phi}^2$ corresponding to subcritical or critical enhancement of the surface interactions. This translates into mesoscopic boundary conditions of the generic symmetry-preserving Robin type $\partial_n\bm{\phi}=\mathring{c}_j\bm{\phi}$. RG-improved perturbation theory and Abel-Plana techniques are used to compute the $L$-dependent part $f_{\mathrm{res}}$ of the reduced excess free energy per film area $A\to\infty$ to two-loop order. When $d<4$, it takes the scaling form $f_{\mathrm{res}}\approx D(c_1L^{\Phi/\nu},c_2L^{\Phi/\nu})/L^{d-1}$ as $L\to\infty$, where $c_i$ are scaling fields associated with the surface-enhancement variables $\mathring{c}_i$, while $\Phi$ is a standard surface crossover exponent. The scaling function $D(\mathsf{c}_1,\mathsf{c}_2)$ and its analogue $\mathcal{D}(\mathsf{c}_1,\mathsf{c}_2)$ for the Casimir force are determined via expansion in $\epsilon=4-d$ and extrapolated to $d=3$ dimensions. In the special case $\mathsf{c}_1=\mathsf{c}_2=0$, the expansion becomes fractional. Consistency with the known fractional expansions of D(0,0) and $\mathcal{D}(0,0)$ to order $\epsilon^{3/2}$ is achieved by appropriate reorganisation of RG-improved perturbation theory. For appropriate choices of $c_1$ and $c_2$, the Casimir forces can have either sign. Furthermore, crossovers from attraction to repulsion and vice versa may occur as $L$ increases.Comment: Latex source file, 40 pages, 9 figure

Effect of angular momentum on equilibrium properties of a self-gravitating system

The microcanonical properties of a two dimensional system of N classical particles interacting via a smoothed Newtonian potential as a function of the total energy E and the total angular momentum L are discussed. In order to estimate suitable observables a numerical method based on an importance sampling algorithm is presented. The entropy surface shows a negative specific heat region at fixed L for all L. Observables probing the average mass distribution are used to understand the link between thermostatistical properties and the spatial distribution of particles. In order to define a phase in non-extensive system we introduce a more general observable than the one proposed by Gross and Votyakov [Eur. Phys. J. B:15, 115 (2000)]: the sign of the largest eigenvalue of the entropy surface curvature. At large E the gravitational system is in a homogeneous gas phase. At low E there are several collapse phases; at L=0 there is a single cluster phase and for L>0 there are several phases with 2 clusters. All these pure phases are separated by first order phase transition regions. The signal of critical behaviour emerges at different points of the parameter space (E,L). We also discuss the ensemble introduced in a recent pre-print by Klinko & Miller; this ensemble is the canonical analogue of the one at constant energy and constant angular momentum. We show that a huge loss of informations appears if we treat the system as a function of intensive parameters: besides the known non-equivalence at first order phase transitions, there exit in the microcanonical ensemble some values of the temperature and the angular velocity for which the corresponding canonical ensemble does not exist, i.e. the partition sum diverges.Comment: 17 pages, 11 figures, submitted to Phys. Rev.

Casimir stress on parallel plates in de Sitter space

The Casimir stress on two parallel plates in de Sitter background for massless scalar field satisfying Robin boundary conditions on the plates is calculated. The metric is written in conformally flat form to make maximum use of the Minkowski space calculations. Different cosmological constants are assumed for the space between and outside of the plates to have general results applicable to the case of domain wall formations in the early universe.Comment: 6 page

Casimir effect for scalar fields with Robin boundary conditions in Schwarzschild background

The stress tensor of a massless scalar field satisfying Robin boundary conditions on two one-dimensional wall in two-dimensional Schwarzschild background is calculated. We show that vacuum expectation value of stress tensor can be obtained explicitly by Casimir effect, trace anomaly and Hawking radiation.Comment: 10 pages, no figure

First Estimations of Cosmological Parameters From BOOMERANG

The anisotropy of the cosmic microwave background radiation contains information about the contents and history of the universe. We report new limits on cosmological parameters derived from the angular power spectrum measured in the first Antarctic flight of the BOOMERANG experiment. Within the framework of inflation-motivated adiabatic cold dark matter models, and using only weakly restrictive prior probabilites on the age of the universe and the Hubble expansion parameter $h$, we find that the curvature is consistent with flat and that the primordial fluctuation spectrum is consistent with scale invariant, in agreement with the basic inflation paradigm. We find that the data prefer a baryon density $\Omega_b h^2$ above, though similar to, the estimates from light element abundances and big bang nucleosynthesis. When combined with large scale structure observations, the BOOMERANG data provide clear detections of both dark matter and dark energy contributions to the total energy density $\Omega_{\rm {tot}}$, independent of data from high redshift supernovae.Comment: As submitted to PRD, revised longer version with an additional figur

Scalar Casimir densities for cylindrically symmetric Robin boundaries

Wightman function, the vacuum expectation values of the field square and the energy-momentum tensor are investigated for a massive scalar field with general curvature coupling parameter in the region between two coaxial cylindrical boundaries. It is assumed that the field obeys general Robin boundary conditions on bounding surfaces. The application of a variant of the generalized Abel-Plana formula allows to extract from the expectation values the contribution from single shells and to present the interference part in terms of exponentially convergent integrals. The vacuum forces acting on the boundaries are presented as the sum of self-action and interaction terms. The first one contains well-known surface divergences and needs a further renormalization. The interaction forces between the cylindrical boundaries are finite and are attractive for special cases of Dirichlet and Neumann scalars. For the general Robin case the interaction forces can be both attractive or repulsive depending on the coefficients in the boundary conditions. The total Casimir energy is evaluated by using the zeta function regularization technique. It is shown that it contains a part which is located on bounding surfaces. The formula for the interference part of the surface energy is derived and the energy balance is discussed.Comment: 22 pages, 5 figure

Improved Measurement of the Angular Power Spectrum of Temperature Anisotropy in the CMB from Two New Analyses of BOOMERANG Observations

We report the most complete analysis to date of observations of the Cosmic Microwave Background (CMB) obtained during the 1998 flight of BOOMERANG. We use two quite different methods to determine the angular power spectrum of the CMB in 20 bands centered at l = 50 to 1000, applying them to 50% more data than has previously been analyzed. The power spectra produced by the two methods are in good agreement with each other, and constitute the most sensitive measurements to date over the range 300 < l < 1000. The increased precision of the power spectrum yields more precise determinations of several cosmological parameters than previous analyses of BOOMERANG data. The results continue to support an inflationary paradigm for the origin of the universe, being well fit by a 13.5 Gyr old, flat universe composed of approximately 5% baryonic matter, 30% cold dark matter, and 65% dark energy, with a scale invariant initial density perturbations.Comment: 26 pages, 15 figures. Higher resolution figures available at http://cmb.phys.cwru.edu/boomerang/ Correction to numbers posted for MADCAP C_l's in Table 2. Correct numbers were used in figures and parameter extractio