Invariant expectations and vanishing of bounded cohomology for exact groups

We study exactness of groups and establish a characterization of exact groups in terms of the existence of a continuous linear operator, called an invariant expectation, whose properties make it a weak counterpart of an invariant mean on a group. We apply this operator to show that exactness of a finitely generated group $G$ implies the vanishing of the bounded cohomology of $G$ with coefficients in a new class of modules, which are defined using the Hopf algebra structure of $\ell_1(G)$.Comment: Final version, to appear in the Journal of Topology and Analysi

Food safety

Illness induced by unsafe food is a problem of great public health significance. This study relates exclusively to the occurrence of chemical agents which will result in food unsafe for human consumption since the matter of food safety is of paramount importance in the mission and operation of the manned spacecraft program of the National Aeronautics and Space Administration

Origin of non-keplerian motions of masers in NGC 1068

We demonstrate that the ``sub-keplerian'' rotation curve of maser spots in NGC 1068 can be explained by the gravitational attraction of the disc orbiting the central black hole. Possible parameters matching observations are: black hole mass of 12 million solar masses, disc outer edge > 1.3 pc, aspect ratio in the range 0.003 to 0.3, surface density varying approximately as 1/R, and disc mass of about 9.4 million solar masses. The physical conditions required for the excitation of masers are fulfilled, and the outer disc would stand in a gravitationally marginally stable state.Comment: 4 pages; accepted in A&A Letter

Workers\u27 Rights Provisions in Fast Track Authority, 1974-2007; An Historical Perspective and Current Analysis

This article examines the trajectory of workers\u27 rights provisions in \u27fast track authority legislation allowing the U.S. president to negotiate free trade agreements that Congress can only approve or reject, not amend. I begin my analysis with the Trade Act of1974 and continue through the expiration of fast track authority in 1994. Against this backdrop, I critique the workers\u27 rights negotiating objectives and priorities in the Bipartisan Trade Promotion Authority Act of 2002 (TPA). Relying on TPA\u27s confused legislative history and basic rules of statutory interpretation, the article seeks to interpret TPA\u27s workers\u27 rights provisions. It concludes by examining the practical implications of TPA\u27s workers\u27 rights negotiating objectives and priorities, as currently applied, by assessing the workers\u27 rights provisions in the trade accords concluded under TPA. Ultimately, I find that, despite pronouncements to the contrary, TPA is a step backward from the Trade Act of 1974, which instructed U.S. trade negotiators to ensure that the global trading system, as governed by GATT included an enforceable requirement hat countries adhere to international fair labor standards. Globalization and the New Politics of Labor, Symposium. Indiana University School of Law-Bloomington, February 11-12, 2005

Workers\u27 Rights Provisions in Fast Track Authority, 1974-2007; An Historical Perspective and Current Analysis

This article examines the trajectory of workers\u27 rights provisions in \u27fast track authority legislation allowing the U.S. president to negotiate free trade agreements that Congress can only approve or reject, not amend. I begin my analysis with the Trade Act of1974 and continue through the expiration of fast track authority in 1994. Against this backdrop, I critique the workers\u27 rights negotiating objectives and priorities in the Bipartisan Trade Promotion Authority Act of 2002 (TPA). Relying on TPA\u27s confused legislative history and basic rules of statutory interpretation, the article seeks to interpret TPA\u27s workers\u27 rights provisions. It concludes by examining the practical implications of TPA\u27s workers\u27 rights negotiating objectives and priorities, as currently applied, by assessing the workers\u27 rights provisions in the trade accords concluded under TPA. Ultimately, I find that, despite pronouncements to the contrary, TPA is a step backward from the Trade Act of 1974, which instructed U.S. trade negotiators to ensure that the global trading system, as governed by GATT included an enforceable requirement hat countries adhere to international fair labor standards. Globalization and the New Politics of Labor, Symposium. Indiana University School of Law-Bloomington, February 11-12, 2005

Quantum State Tomography Using Successive Measurements

We describe a quantum state tomography scheme which is applicable to a system described in a Hilbert space of arbitrary finite dimensionality and is constructed from sequences of two measurements. The scheme consists of measuring the various pairs of projectors onto two bases --which have no mutually orthogonal vectors--, the two members of each pair being measured in succession. We show that this scheme implies measuring the joint quasi-probability of any pair of non-degenerate observables having the two bases as their respective eigenbases. The model Hamiltonian underlying the scheme makes use of two meters initially prepared in an arbitrary given quantum state, following the ideas that were introduced by von Neumann in his theory of measurement.Comment: 12 Page

Constraining planet formation around 6M⊙-8M⊙ stars

Identifying planets around O-type and B-type stars is inherently difficult; the most massive known planet host has a mass of only about 3M⊙. However, planetary systems which survive the transformation of their host stars into white dwarfs can be detected via photospheric trace metals, circumstellar dusty and gaseous discs, and transits of planetary debris crossing our line-of-sight. These signatures offer the potential to explore the efficiency of planet formation for host stars with masses up to the core-collapse boundary at ≈8M⊙, a mass regime rarely investigated in planet formation theory. Here, we establish limits on where both major and minor planets must reside around ≈6M⊙ − 8M⊙ stars in order to survive into the white dwarf phase. For this mass range, we find that intact terrestrial or giant planets need to leave the main sequence beyond approximate minimum star-planet separations of respectively about 3 and 6 au. In these systems, rubble pile minor planets of radii 10, 1.0, and 0.1 km would have been shorn apart by giant branch radiative YORP spin-up if they formed and remained within, respectively, tens, hundreds and thousands of au. These boundary values would help distinguish the nature of the progenitor of metal-pollution in white dwarf atmospheres. We find that planet formation around the highest mass white dwarf progenitors may be feasible, and hence encourage both dedicated planet formation investigations for these systems and spectroscopic analyses of the highest mass white dwarfs

Regulation of NF-κB by PML and PML-RARα

Promyelocytic Leukemia (PML) is a nuclear protein that forms sub-nuclear structures termed nuclear bodies associated with transcriptionally active genomic regions. PML is a tumour suppressor and regulator of cell differentiation. We demonstrate that PML promotes TNFα-induced transcriptional responses by promoting NF-κB activity. TNFα-treated PML−/− cells show normal IκBα degradation and NF-κB nuclear translocation but significantly reduced NF-κB DNA binding and phosphorylation of NF-κB p65. We also demonstrate that the PML retinoic acid receptor-α (PML-RARα) oncofusion protein, which causes acute promyelocytic leukemia, inhibits TNFα induced gene expression and phosphorylation of NF-κB. This study establishes PML as an important regulator of NF-κB and demonstrates that PML-RARα dysregulates NF-κB