165 research outputs found

    Improving SN Ia Distance Measurements Through Better Understanding of SN Ia Systematic Uncertainties

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    Distance measurements using Type Ia Supernovae have enabled the startling discovery that the expansion of the universe is accelerating. To determine the nature and the source of this acceleration, systematic uncertainties on distance measurement must be reduced. Due to their importance to high-redshift optical SN Ia cosmology and their sensitivity to dust and progenitor metallicity effects, understanding rest-frame near-UV (NUV) measurements of Type Ia SNe is key to reducing these systematic uncertainties. Unfortunately, the calibration and acquisition of this data is challenging. We use direct comparisons of low-redshift SDSS-II and Carnegie Supernova Project NUV SN Ia photometry to quantify uncertainties on our ability to calibrate observer frame observations, and find that photometry in this region is consistent at the level of 2% in flux with a 6% scatter about the mean. Monte Carlo simulated SN Ia samples are used to directly measure Hubble Diagram biases resulting from SN Ia model training. Four simulated SN Ia samples are used to train the SALT-II SN Ia model: two width-luminosity adjustments and two intrinsic scatter models are tested. Adding intrinsic scatter to the training sample yields biased color laws and wavelength-dependent scatter in the NUV region, and causes the color correction parameter ÎČ to be systematically underestimated. Assuming a flat ΛCDM cosmology and including BAO and CMB constraints, three of our tests correctly recover the Dark Energy equation of state parameter w. The fourth test gives a w offset of 0.02, with a 4-σ significance. The software developed to support this work may be adapted to measure Hubble Diagram biases for any combination of SN Ia model and surveys

    The Costs of Justice in Domestic Violence Cases : Mapping Canadian Law and Policy

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    Domestic violence cases in Canada present unique access to justice challenges due to complex power dynamics, structural inequality, and the fact that victims, offenders, and children must often navigate multiple legal systems to resolve the many issues in this context. The complexity of these cases has both personal and systemic impacts. Different legal systems – for example, criminal, family, child protection, social welfare, and immigration – have differing objectives and personnel with varying levels of expertise in domestic violence. Conflicting decisions by different courts and tribunals with overlapping jurisdiction may impair the safety of victims and children, and may require multiple court appearances to resolve. Victims may face contradictory messages about how seriously adjudicators will treat domestic violence, and offenders can use the existence of different systems to perpetuate abuse. These issues are gendered, as women are the primary victims of domestic violence, and the concerns may be heightened among marginalized women. The issues may also differ across Canadian provinces and territories and on First Nations reserves, given the application of different laws, policies, and dispute resolution models. This chapter explores how the access to justice crisis in Canada manifests itself in domestic violence cases. It reviews the literature on access to justice and domestic violence, adopting a broad definition of access to justice to inform the analysis. It then documents and compares the legal and policy provisions and systems affecting litigants in domestic violence cases across Canadian jurisdictions, highlighting legal reforms as well as the systemic barriers in seeking justice that victims, offenders, and children confront. A hypothetical case study is then used to explore how the complex interaction of multiple laws, policies, and dispute resolution processes may impact victims of domestic violence. This comparative mapping analysis is a first step towards identifying the systemic reforms necessary to enhance access to justice in domestic violence cases

    A Comparison of Gender-Based Violence Laws in Canada: A Report for the National Action Plan on Gender-Based Violence Working Group on Responsive Legal and Justice Systems

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    This report undertakes a comparison of laws related to gender-based violence across Canada with a view to identifying promising practices. We use the definition of gender-based violence from the United Nations as our frame, analyzing laws relating to “any act of gender-based violence that results in, or is likely to result in, physical, sexual, or mental harm or suffering to women, including threats of such acts, coercion or arbitrary deprivation of liberty, whether occurring in public or in private life.” While the UN definition includes both intimate partner violence and sexual violence, our focus is largely on violence in the context of intimate relationships (including intimate partner sexual violence). We are guided by a broad conception of access to procedural and substantive justice that encompasses equal protection of the law, equal access to legal rights and remedies, and safety for women and children

    The experience of parental illness : a heuristic arts-based inquiry

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    This research addresses the author's experience with parental illness and how can that experience be explored and understood through a heuristic arts-based methodology. The integration of the use of artwork within the heuristic framework is addressed and the author's experience with this process outlined. Art-making was used as the primary means of exploration and analysis of the question, which lead to greater understanding, awareness and acceptance within the author. Theory and research related to parental illness is outlined and compared to the findings gleaned through the heuristic arts-based methodology used in the present study

    Submission to Justice Canada on the Criminalization of Coercive Control

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    Justice Canada has been holding an engagement process on the issue of whether an offence of coercive control should be added to the Criminal Code. This offence has been proposed in a series of private members bills, most recently, Bill C-332. This submission argues that it is imperative that actors in all legal domains acquire a nuanced and contextual understanding of coercive control derived from an intersectional analysis that attends to how multiple systems of oppression interact to shape the tactics of coercion and control. However, we do not support the criminalization of coercive control, either as a standalone offence or within a broader offence of domestic abuse / violence. We argue that it is the former approach – the acquisition of deep and contextualized knowledge – and not criminalization that holds promise in enhancing safety for women and children. In Part B, we provide a brief overview of coercive control. This overview highlights some areas of contestation, with a view to illuminating the many challenges of translating the theory of coercive control into a criminal prohibition as well as the complex intersectional understanding of coercive control that legal system actors need to acquire. In Part C, we examine lessons learned from past and current criminalization initiatives. Here we address the differential impacts of criminalization, and based on the expertise of co-author Harris, we focus on the experiences of Black women. These lessons, we argue, underscore not only the lack of efficacy of criminalization in enhancing safety, but its infliction of harm on survivors of violence, particularly those who are marginalized. In Part D, we consider what can be learned from recent Divorce Act reforms regarding the translation of coercive control into the legal realm in the context of parenting disputes. Our preliminary case law review reinforces concerns about the difficulty courts have in seeing coercive control and its possible weaponization against survivors (see a list of cases we discuss in Appendix A). In Part E, we explore lessons learned through the ongoing research of co-authors Mosher, Koshan, and Wiegers on intersecting legal domains, including the family law, child protection, civil protection order, and immigration systems, as well as the ways in which these intersecting systems can be manipulated by abusers. In Part F we summarize the reasons why we do not support the creation of a new criminal offence and explain why Bill C-332 is particularly problematic (see also a summary of the Bill at Appendix B). We offer concluding suggestions as to what should be done to address coercive control and gender-based violence

    Introduction: Domestic Violence and Access to Justice within the Family Law and Intersecting Legal Systems

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    The articles in this collection explore the access to justice issues that arise for survivors of domestic violence in their encounters with Canada’s family law system. While family law and family dispute resolution processes are the central focus of the articles, three contributions also address family law\u27s intersections with other legal domains (civil restraining orders, child welfare, and immigration). Common across the contributions is a desire to carefully interrogate the potential of law and legal processes to enhance—or conversely to undermine—the safety and well-being of survivors and their children

    Introduction: Domestic Violence and Access to Justice within the Family Law and Intersecting Legal Systems

    Get PDF
    The articles in this collection explore the access to justice issues that arise for survivors of domestic violence in their encounters with Canada’s family law system. While family law and family dispute resolution processes are the central focus of the articles, three contributions also address family law\u27s intersections with other legal domains (civil restraining orders, child welfare, and immigration). Common across the contributions is a desire to carefully interrogate the potential of law and legal processes to enhance—or conversely to undermine—the safety and well-being of survivors and their children

    Self-efficacy for coping with cancer in a multiethnic sample of breast cancer patients: Associations with barriers to pain management and distress

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    Objectives This study examined the interrelations of self-efficacy for coping with cancer, perceived barriers to pain management, distress, and pain outcomes in a multiethnic sample of breast cancer patients. The extent to which ethnicity (Black, Latina, or White), language (English or Spanish), and level of education and income predicted these variables was also assessed. Methods Participants were breast cancer patients with persistent pain (N=87) who were recruited from oncology clinics in New York City. Patients completed an assessment battery that included measures of self-efficacy for coping with cancer, barriers to pain management, distress, and pain outcomes. Results Greater self-efficacy for coping with cancer was associated with older age, less time since diagnosis, and less distress. In addition, less self-efficacy for seeking and understanding medical information, Spanish language preference, and greater distress predicted greater barriers to pain management. Average pain severity was higher among Spanish-speaking individuals and those with lower incomes. Discussion Findings point to the potential importance of self-efficacy for seeking and understanding medical information and perceived barriers to pain management in understanding the psychologic well-being of breast cancer patients with pain, especially those who are Spanish-speaking

    Establishment and metabolic analysis of a model microbial community for understanding trophic and electron accepting interactions of subsurface anaerobic environments

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    <p>Abstract</p> <p>Background</p> <p>Communities of microorganisms control the rates of key biogeochemical cycles, and are important for biotechnology, bioremediation, and industrial microbiological processes. For this reason, we constructed a model microbial community comprised of three species dependent on trophic interactions. The three species microbial community was comprised of <it>Clostridium cellulolyticum</it>, <it>Desulfovibrio vulgaris </it>Hildenborough, and <it>Geobacter sulfurreducens </it>and was grown under continuous culture conditions. Cellobiose served as the carbon and energy source for <it>C. cellulolyticum</it>, whereas <it>D. vulgaris </it>and <it>G. sulfurreducens </it>derived carbon and energy from the metabolic products of cellobiose fermentation and were provided with sulfate and fumarate respectively as electron acceptors.</p> <p>Results</p> <p>qPCR monitoring of the culture revealed <it>C. cellulolyticum </it>to be dominant as expected and confirmed the presence of <it>D. vulgaris </it>and <it>G. sulfurreducens</it>. Proposed metabolic modeling of carbon and electron flow of the three-species community indicated that the growth of <it>C. cellulolyticum </it>and <it>D. vulgaris </it>were electron donor limited whereas <it>G. sulfurreducens </it>was electron acceptor limited.</p> <p>Conclusions</p> <p>The results demonstrate that <it>C. cellulolyticum</it>, <it>D. vulgaris</it>, and <it>G. sulfurreducens </it>can be grown in coculture in a continuous culture system in which <it>D. vulgaris </it>and <it>G. sulfurreducens </it>are dependent upon the metabolic byproducts of <it>C. cellulolyticum </it>for nutrients. This represents a step towards developing a tractable model ecosystem comprised of members representing the functional groups of a trophic network.</p

    Testing Models of Intrinsic Brightness Variations in Type Ia Supernovae, and their Impact on Measuring Cosmological Parameters

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    For spectroscopically confirmed Type Ia supernovae we evaluate models of intrinsic brightness variations with detailed data/Monte Carlo comparisons of the dispersion in the following quantities: Hubble-diagram scatter, color difference (B-V-c) between the true B-V color and the fitted color (c) from the SALT-II light curve model, and photometric redshift residual. The data sample includes 251 ugriz light curves from the 3-season Sloan Digital Sky Survey-II, and 191 griz light curves from the Supernova Legacy Survey 3-year data release. We find that the simplest model of a wavelength-independent (coherent) scatter is not adequate, and that to describe the data the intrinsic scatter model must have wavelength-dependent variations. We use Monte Carlo simulations to examine the standard approach of adding a coherent scatter term in quadrature to the distance-modulus uncertainty in order to bring the reduced chi2 to unity when fitting a Hubble diagram. If the light curve fits include model uncertainties with the correct wavelength dependence of the scatter, we find that the bias on the dark energy equation of state parameter ww is negligible. However, incorrect model uncertainties can lead to a significant bias on the distance moduli, with up to ~0.05 mag redshift-dependent variation. For the recent SNLS3 cosmology results we estimate that this effect introduces an additional systematic uncertainty on ww of ~0.02, well below the total uncertainty. However, this uncertainty depends on the samples used, and thus this small ww-uncertainty is not guaranteed in future cosmology results.Comment: accepted by Ap
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