r-Java 2.0: the nuclear physics

[Aims:] We present r-Java 2.0, a nucleosynthesis code for open use that performs r-process calculations as well as a suite of other analysis tools. [Methods:] Equipped with a straightforward graphical user interface, r-Java 2.0 is capable of; simulating nuclear statistical equilibrium (NSE), calculating r-process abundances for a wide range of input parameters and astrophysical environments, computing the mass fragmentation from neutron-induced fission as well as the study of individual nucleosynthesis processes. [Results:] In this paper we discuss enhancements made to this version of r-Java, paramount of which is the ability to solve the full reaction network. The sophisticated fission methodology incorporated into r-Java 2.0 which includes three fission channels (beta-delayed, neutron-induced and spontaneous fission) as well as computation of the mass fragmentation is compared to the upper limit on mass fission approximation. The effects of including beta-delayed neutron emission on r-process yield is studied. The role of coulomb interactions in NSE abundances is shown to be significant, supporting previous findings. A comparative analysis was undertaken during the development of r-Java 2.0 whereby we reproduced the results found in literature from three other r-process codes. This code is capable of simulating the physical environment of; the high-entropy wind around a proto-neutron star, the ejecta from a neutron star merger or the relativistic ejecta from a quark nova. As well the users of r-Java 2.0 are given the freedom to define a custom environment. This software provides an even platform for comparison of different proposed r-process sites and is available for download from the website of the Quark-Nova Project: http://quarknova.ucalgary.ca/Comment: 26 pages, 18 figures, 1 tabl

Why are criminals less educated than non-criminals? Evidence from a cohort of young Australian twins

This paper investigates the question whether crime reduces investment in human capital or whether education reduces criminal activity by using fixed effect estimation on data of Australian twins. The study takes genetic and socio-economic factors shared by the twins into account.�We find that early arrests (before the age of 18) have a strong effect on human capital accumulation. In addition, we find that education decreases crime. However, controlling for early arrests and early behaviour problems reduces the estimated effect of human capital on crime to less than on third of the previously estimated association. From this, we conclude that the strong association between human capital and crime is mainly driven by the effect of early criminal behaviour on educational attainment. The strong detrimental effects of early criminal behaviour become also transparent if we consider the estimated effects of early arrests on three measures of crime. We also find large effects of early criminal behaviour on participation in crime later on. This suggests that programs that succeed in preventing early criminal behaviour might yield high social and private returns.

The effect of childhood conduct disorder on human capital

This paper estimates the longer-term effects of childhood conduct disorder on human capital accumulation and violent and criminal behaviour later in life using data of Australian twins. We measure conduct disorder with a rich set of indicators based on diagnostic criteria from psychiatry (e.g., aggression to people and animals, destruction of property, deceitfulness or theft, and/or serious violations of rules). Using ordinary least squares (OLS) and twin fixed effects (FE) estimation approaches, we find that early (pre-18) conduct disorder problems significantly affect both human capital accumulation and violent and criminal behaviour over the life course. For instance, within pairs of identical twins we find that conduct disorder reduces the probability of high school graduation with 4 to 13 percent points and increases the probability of being arrested with 7 to 16 percent points. Robustness checks suggest that these estimates may be lower bounds of the true effects of conduct disorder. In addition, we find that conduct disorder is more deleterious if these behaviours occur earlier in life. We conclude that childhood mental health problems have high human and financial costs for families and society at large. Effective treatments early in life might yield high returns.

The ever unfolding story of cAMP signaling in trypanosomatids: vive la difference!

Kinetoplastids are unicellular, eukaryotic, flagellated protozoans containing the eponymous kinetoplast. Within this order, the family of trypanosomatids are responsible for some of the most serious human diseases, including Chagas disease (Trypanosoma cruzi), sleeping sickness (Trypanosoma brucei spp.), and leishmaniasis (Leishmania spp). Although cAMP is produced during the life cycle stages of these parasites, its signaling pathways are very different from those of mammals. The absence of G-protein-coupled receptors, the presence of structurally different adenylyl cyclases, the paucity of known cAMP effector proteins and the stringent need for regulation of cAMP in the small kinetoplastid cells all suggest a significantly different biochemical pathway and likely cell biology. However, each of the main kinetoplastid parasites express four class 1-type cyclic nucleotide-specific phosphodiesterases (PDEA-D), which have highly similar catalytic domains to that of human PDEs. To date, only TbrPDEB, expressed as two slightly different isoforms TbrPDEB1 and B2, has been found to be essential when ablated. Although the genomes contain reasonably well conserved genes for catalytic and regulatory domains of protein kinase A, these have been shown to have varied structural and functional roles in the different species. Recent discovery of a role of cAMP/AMP metabolism in a quorum-sensing signaling pathway in T. brucei, and the identification of downstream cAMP Response Proteins (CARPs) whose expression levels correlate with sensitivity to PDE inhibitors, suggests a complex signaling cascade. The interplay between the roles of these novel CARPs and the quorum-sensing signaling pathway on cell division and differentiation makes for intriguing cell biology and a new paradigm in cAMP signal transduction, as well as potential targets for trypanosomatid-specific cAMP pathway-based therapeutics

Post Asymptotic Giant Branch Bipolar Reflection Nebulae: Result of Dynamical Ejection or Selective Illumination?

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Morphology of the red rectangle proto-planetary nebula

Poster no. 94Using the 3D morpho-kinematic modeling software SHAPE, we have created a model of the Red Rectangle that naturally reproduces many exotic morphological features including the notorious "ladder rungs". © 2012 International Astronomical Union.published_or_final_versionThe IAU Symposium No. 283: 'Planetary Nebulae: an Eye to the Future', Puerto de la Cruz, Tenerife, Spain, 25-29 July 2011. In International Astronomical Union Proceedings, 2012, v. 7 n. S283, p. 410-41

Organizational ethnography and religious organizations: the case of Quaker decision-making

How should we study the management practices of religious organizations to do justice to their distinctive religious motivations and traditions? In this article, we articulate how a specific research approach – organizational ethnography – may enable a deeper understanding of religious and/or spiritual organizational practice. We approach our methodological research questions by engaging with the literature on the distinctive decision-making practices of the Religious Society of Friends (Quakers), commonly known as the Quaker business method. Having shown that the Quaker business method destabilizes a simple binary between “insider” and “outsider” and between believers and nonbelievers, we bring the theory and practice of organizational ethnography into conversation with Quaker accounts of decision-making. We conclude with pathways for future research in the space this destabilization creates