The BIC of a singular foliation defined by an abelian group of isometries

We study the cohomology properties of the singular foliation \F determined by an action $\Phi \colon G \times M\to M$ where the abelian Lie group $G$ preserves a riemannian metric on the compact manifold $M$. More precisely, we prove that the basic intersection cohomology \lau{\IH}{*}{\per{p}}{\mf} is finite dimensional and verifies the Poincar\'e Duality. This duality includes two well-known situations: -- Poincar\'e Duality for basic cohomology (the action $\Phi$ is almost free). -- Poincar\'e Duality for intersection cohomology (the group $G$ is compact and connected)

Long-term polarimetric observations of OH127.8+0.0

OH 1612 and 1667 MHz masers from the well known object OH127.8+0.0 were mon- itored in full-polarization mode over a period of 6.5 years and mapped with MERLIN at one epoch. The OH variability pattern of the star is typical of extremely long- period AGB stars. The distance determined from the 1612 MHz light curve and a new measurement of the angular radius is 3.87 (0.28) kpc. At both frequencies, the flux of polarized emission tightly follows the total flux variations while, the degrees of circu- lar and linear polarization are constant within measurement accuracy.. There is net polarization at both lines. The magnetic field strength estimated from a likely Zeeman pair is -0.6 mG at the distance of 5400 au from the star.At the near and far sides of the envelope, the polarization vectors are well aligned implying a regular structure of the magnetic field. The polarization characteristics of the OH maser emission suggest a radial magnetic field which is frozen in the stellar wind.Comment: 12 pages, 9 figure

Top dimensional group of the basic intersection cohomology for singular riemannian foliations

It is known that, for a regular riemannian foliation on a compact manifold, the properties of its basic cohomology (non-vanishing of the top-dimensional group and Poincar\'e Duality) and the tautness of the foliation are closely related. If we consider singular riemannian foliations, there is little or no relation between these properties. We present an example of a singular isometric flow for which the top dimensional basic cohomology group is non-trivial, but its basic cohomology does not satisfy the Poincar\'e Duality property. We recover this property in the basic intersection cohomology. It is not by chance that the top dimensional basic intersection cohomology groups of the example are isomorphic to either 0 or $\mathbb{R}$. We prove in this Note that this holds for any singular riemannian foliation of a compact connected manifold. As a Corollary, we get that the tautness of the regular stratum of the singular riemannian foliation can be detected by the basic intersection cohomology.Comment: 11 pages. Accepted for publication in the Bulletin of the Polish Academy of Science

Trends in Unwanted Online Experiences and Sexting : Final Report

This bulletin summarizes findings from the Third Youth Internet Safety Survey (YISS‐3). Topics include youth reports of unwanted sexual solicitations, online harassment, unwanted exposure to sexual material, and “sexting.

Accounting for genetic differences among unknown parents in microevolutionary studies : how to include genetic groups in quantitative genetic animal models

This work was funded by a European Research Council Starting Grant to JMR. We thank Loeske Kruuk, Karin Meyer, Michael Morrissey, Simon Evans, Jarrod Hadfield and an anonymous reviewer for their helpful comments and insights.Peer reviewedPublisher PD

Is Pairing with a Relative Heritable? : Estimating Female and Male Genetic Contributions to the Degree of Biparental Inbreeding in Song Sparrows (Melospiza melodia)

Acknowledgments We thank the Tsawout and Tseycum First Nation bands for access to Mandarte, P. Arcese and everyone who contributed to the long‐term data collection, and the European Research Council and Royal Society for funding. We thank P. Bijma, J. D. Hadfield, L. F. Keller, and E. Postma for illuminating discussions. In addition, R. Bonduriansky, L. E. B. Kruuk, and an anonymous reviewer provided insightful comments that improved the manuscript.Peer reviewedPublisher PD