A Framework for Assessing the Rationality of Judgments in Carcinogenicity Hazard Identification

Arguing that guidelines for identifying carcinogens now lack a philosophically rigorous framework, the authors present an alternative that draws clear attention to the process of reasoning towards judgments of carcinogenicity

Comparative Venture Capital Governance. Private versus Labour Sponsored Venture Capital Funds

Private independent limited partnership venture capital funds receive capital from institutional investors, without tax incentives. Limited partnership investment activities are governed by restrictive covenants that are determined by negotiated contract between the fund managers (general partners) and the institutional investors (limited partners). By contrast, Canadian Labour Sponsored Venture Capital Corporations (LSVCCs) receive capital only from individual investors who receive tax breaks on capital contributions of up to CAN$5,000. LSVCC investment activities are governed by statutory restrictions. This chapter contrasts the governance of LSVCCs to limited partnerships. We also summarize Canadian evidence on the impact of LSVCC governance and tax incentives: (1) on the distribution of venture capital funding between private and LSVCC funds; (2) on the unusually large overhang of uninvested capital in the Canadian venture capital industry; (3) the portfolio size (i.e. number of investee firms per fund) of private funds versus LSVCCs; and (4) the performance of LSVCCs relative to other types of venture capital organiziations and other comparable investments for individual investors.venture capital, Canada, tax, government, crowding out, portfolio size, governance

Magnetic suspension systems for space applications

An overview of techniques is presented used in the described magnetic suspension systems. Also a review is presented of the systems already developed, which demonstrate the usefulness, applicability, and flight readiness of magnetic suspension to a broad range of payloads and environments. The following subject areas are covered: programs overview; key concepts; magnetic suspension as an isolator and as a pointer; pointing and isolation systems; magnetic actuator control techniques; and test data

Max-min Fairness in 802.11 Mesh Networks

In this paper we build upon the recent observation that the 802.11 rate region is log-convex and, for the first time, characterise max-min fair rate allocations for a large class of 802.11 wireless mesh networks. By exploiting features of the 802.11e/n MAC, in particular TXOP packet bursting, we are able to use this characterisation to establish a straightforward, practically implementable approach for achieving max-min throughput fairness. We demonstrate that this approach can be readily extended to encompass time-based fairness in multi-rate 802.11 mesh networks

Exploring taboo issues in professional sport through a fictional approach

While the need to consider life course issues in elite sport research and practice is increasingly recognised, some experiences still seem to be considered too dangerous to explore. Consequently, stories of these experiences are silenced and the ethical and moral questions they pose fail to be acknowledged, understood or debated. This paper presents an ethnographic fiction through which we explore a sensitive set of experiences that were uncovered during our research with professional sportspeople. Through a multi‐layered reconstruction, the story reveals the complex, but significant, relationships that exist between identity, cultural narratives and embodied experiences. After the telling we consider how the story has stimulated reflective practice among students, researchers and practitioners. While there are risks involved in writing and sharing taboo stories, the feedback we have received suggests that storytelling can be an effective pedagogical tool in education and professional development

A New Solution of The Cosmological Constant Problems

We extend the usual gravitational action principle by promoting the bare cosmological constant (CC) from a parameter to a field which can take many possible values. Variation leads to a new integral constraint equation which determines the classical value of the effective CC that dominates the wave function of the universe. In a realistic cosmological model, the expected value of the effective CC, is calculated from measurable quantities to be O(t_U), as observed, where t_U is the present age of the universe in Planck units,. Any application of our model produces a falsifiable prediction for $\Lambda$ in terms of other measurable quantities. This leads to a specific falsifiable prediction for the observed spatial curvature parameter of Omega_k0=-0.0055. Our testable proposal requires no fine tunings or extra dark-energy fields but does suggest a new view of time and cosmological evolution.Comment: 5 pages; v3: version accepted by Phys. Rev. Let

De novo Development and Characterization of Tetranucleotide Microsatellite Loci Markers from a Southeastern Population of the House Finch (Haemorhous mexicanus)

Microsatellites are short tandem repeats (e.g. TAGATAGA) of base pairs in a species’ genome. High mutation rates in these regions produce variation in the number of repeats across individuals that can be utilized to study patterns of population- and landscape-level genetics and to determine parentage genetically. In this project our objective was to develop microsatellite markers for the House Finch, Haemorhous mexicanus. This species has become one of the most well-studied species of songbirds due to its unique geographical, evolutionary, and epidemiological history. Using mist-nets we captured birds on the Arkansas Tech University campus and collected blood samples to obtain genomic DNA. Samples were processed in The Field Museum’s Pritzker Laboratory for Molecular Systematics and Evolution, where we fragmented genomic DNA and isolated fragments that contained potential microsatellites using specially designed biotin labelled probes. These DNA fragments were transformed into competent E. coli cells which were then PCR-amplified and Sanger sequenced. After sequencing DNA fragments from approximately 500 E. coli colonies, we designed and characterized a set of 13 tetranucleotide microsatellite loci. The average number of alleles and heterozygosity found in 12 individuals from Arkansas was 8.69 and 0.80, respectively. This finalized set of microsatellites can be utilized by researchers to determine parentage and characterize genetic differences across House Finch populations

The Class Size Controversy

[Excerpt] When we ask whether class size matters for achievement, it is essential to ask also, how class size matters. This is important for three reasons. First, if we can observe not only achievement differences, but also the mechanisms through which the differences are produced, this will increase our confidence that the differences are real, and not an artifact of some unmeasured or inadequately controlled condition. Second, the effects of class size may vary in different circumstances, and identifying how class size affects achievement will help us to understand why the effects of class size are variable. Third, the potential benefits of class size reduction may be greater than what we observe. For example, suppose class size reductions aid achievement, but only when teachers modify instructional practices to take advantage of the smaller classes. If a few teachers make such modifications, but most do not, then understanding how class size affects achievement in some cases will help reveal its potential effects, even if the potential is generally unrealized

Toeplitz algebras and spectral results for the one-dimensional Heisenberg model

We determine the structure of the spectrum and obtain non-propagation estimates for a class of Toeplitz operators acting on a subset of the lattice $\Z^N$. This class contains the Hamiltonian of the one-dimensional Heisenberg model.Comment: 13 page