Indeterminate-length quantum coding

The quantum analogues of classical variable-length codes are indeterminate-length quantum codes, in which codewords may exist in superpositions of different lengths. This paper explores some of their properties. The length observable for such codes is governed by a quantum version of the Kraft-McMillan inequality. Indeterminate-length quantum codes also provide an alternate approach to quantum data compression.Comment: 32 page

Calculation of steady and unsteady pressures at supersonic speeds with CAP-TSD

A finite difference technique is used to solve the transonic small disturbance flow equation making use of shock capturing to treat wave discontinuities. Thus the nonlinear effects of thickness and angle of attack are considered. Such an approach is made feasible by the development of a new code called CAP-TSD (Computational Aeroelasticity Program - Transonic Small Disturbance), and is based on a fully implicit approximate factorization (AF) finite difference method to solve the time dependent transonic small disturbance equation. The application of the CAP-TSD code to the calculation of low to moderate supersonic steady and unsteady flows is presented. In particular, comparisons with exact linear theory solutions are made for steady and unsteady cases to evaluate shock capturing and other features of the current method. In addition, steady solutions obtained from an Euler code are used to evaluate the small disturbance aspects of the code. Steady and unsteady pressure comparisons are made with measurements for an F-15 wing model and for the RAE tailplane model

Examining Tension in the Provision of Palliative Care: Social Workers’ Experiences

This dissertation was a qualitative study that explored workplace tension experienced by social workers employed in palliative care settings in Ontario, Canada. Although work in palliative care can be a rewarding, it can also be challenging for a myriad of reasons, including the emotional labour of the work and organizational factors. While many of these challenges are common among most providers, social workers face unique difficulties. Social workers employed in palliative care settings are exposed to existential dilemmas, psychological quandaries, emotional distress, and confront institutional and professional challenges associated with working within the medical model and neoliberal ideologies that dominate many of these institutions. Although tension frequently appears in the palliative care literature, it has multiple and varying uses and defies a definition that fits every professional and every situation. Few research studies have attempted to understand workplace tension with a specific focus on how structural and relational forces conjoin and contribute to it, and even fewer sample social workers specifically. The purpose of this study was to gain a deep and rich understanding of workplace tension and identify its origins and the factors that perpetuate and sustain it. Using an interlocking theoretical perspective, the works of Foucault and Goffman were intertwined and juxtaposed to gain an understanding of the source of workplace tension in both the formation and structure of discourse and how it is expressed and experienced in face-to-face interactions. The following research questions were used to guide this study: 1) How do social workers employed in palliative care settings define and describe the term tension? 2) What are the individual, relational, and organizational sources of workplace tension? and 3) How do social workers in palliative care settings manage everyday workplace tension? The experiences of 13 social workers employed in palliative care settings are presented. The work was methodologically grounded in the theoretical paradigm of interpretive description and is informed by Foucault’s writings on power and discourse and Goffman’s theory of presentation-of-self. Data was collected using unstructured interviews. Participants understanding of tension was explored, and four overarching themes pertaining to sources of workplace tension emerged: (a) social workers’ perception of their own reality in palliative care settings; (b) social workers’ reflections of how others see them; (c) tension between these two perceptions of reality; and (d) managing and balancing tension. Participants described concerns regarding the minimization and misunderstanding of social work knowledge and training. Concerns were exacerbated by organizational hierarchies and the devaluing and disempowering of social workers in workplace settings. Participants also discussed role strain and role conflict that resulted from fulfilling several roles. Participants endeavoured to maintain a favourable impression with their colleagues, clients, and organization administration by practices such as using euphemisms, disarming techniques, role distancing techniques. The findings from this study highlight elements of power and social control and ways in which social contexts produce social practices and daily interactions. Study implications include the need to question, dismantle, and challenge the dominance of the medical model and reposition social workers employed in palliative care settings in order to reduce workplace tension

Structural Studies on a Mitochondrial Glyoxalase II

Glyoxalase 2 is a β-lactamase fold-containing enzyme that appears to be involved with cellular chemical detoxification. Although the cytoplasmic isozyme has been characterized from several organisms, essentially nothing is known about the mitochondrial proteins. As a first step in understanding the structure and function of mitochondrial glyoxalase 2 enzymes, a mitochondrial isozyme (GLX2-5) from Arabidopsis thaliana was cloned, overexpressed, purified, and characterized using metal analyses, EPR and 1H NMR spectroscopies, and x-ray crystallography. The recombinant enzyme was shown to bind 1.04 ± 0.15 eq of iron and 1.31 ± 0.05 eq of Zn(II) and to exhibit kcat and Km values of 129 ± 10 s-1 and 391 ± 48 μm, respectively, when using S-d-lactoylglutathione as the substrate. EPR spectra revealed that recombinant GLX2-5 contains multiple metal centers, including a predominant Fe(III)Z-n(II) center and an anti-ferromagnetically coupled Fe(III)Fe(II) center. Unlike cytosolic glyoxalase 2 from A. thaliana, GLX2-5 does not appear to specifically bind manganese. 1H NMR spectra revealed the presence of at least eight paramagnetically shifted resonances that arise from protons in close proximity to a Fe(III)Fe(II) center. Five of these resonances arose from solvent-exchangeable protons, and four of these have been assigned to NH protons on metal-bound histidines. A 1.74-Å resolution crystal structure of the enzyme revealed that although GLX2-5 shares a number of structural features with human GLX2, several important differences exist. These data demonstrate that mitochondrial glyoxalase 2 can accommodate a number of different metal centers and that the predominant metal center is Fe(III)Zn(II)

Association of urinary uromodulin with kidney function decline and mortality: the health ABC study .

BackgroundUrine uromodulin (uUMOD) is a protein secreted by the kidney tubule. Recent studies have suggested that higher uUMOD may be associated with improved kidney and mortality outcomes.MethodsUsing a case-cohort design, we evaluated the association between baseline uUMOD levels and ≥ 30% estimated glomerular filtration rate (eGFR) decline, incident chronic kidney disease (CKD), rapid kidney function decline, and mortality using standard and modified Cox proportional hazards regression.ResultsThe median value of uUMOD was 25.8 µg/mL, mean age of participants was 74 years, 48% were women, and 39% were black. Persons with higher uUMOD had lower prevalence of diabetes and coronary artery disease (CAD), and had lower systolic blood pressure. Persons with higher uUMOD also had higher eGFR, lower urinary albumin to creatinine ratio (ACR), and lower C-reactive protein (CRP). There was no association of uUMOD with > 30% eGFR decline. In comparison to those in the lowest quartile of uUMOD, those in the highest quartile had a significantly (53%) lower risk of incident CKD (CI 73%, 18%) and a 51% lower risk of rapid kidney function decline (CI 76%, 1%) after multivariable adjustment. Higher uUMOD was associated with lower risk of mortality in demographic adjusted models, but not after multivariable adjustment.ConclusionHigher levels of uUMOD are associated with lower risk of incident CKD and rapid kidney function decline. Additional studies are needed in the general population and in persons with advanced CKD to confirm these findings.


Energetic Benefits of Sociality Offset the Costs of Parasitism in a Cooperative Mammal

We thank the owners for access to their property for animal capture and KwaZulu-Natal Nature Conservation Service for issuing the capture permit. This research was funded by the NRF-SAR Chair for Mammalian Behavioural Ecology and Physiology to NCB and University of Pretoria PDRF's to MS and HL. Many assistants were involved with fieldwork but we would especially like to thank Marietjie Oosthuizen and Craig Jackson for their help. This research was funded by the Department of Science and Technology/National Research Foundation-South African Research Chairs Initiative Chair for Mammalian Behavioural Ecology and Physiology to N.C.B. and University of Pretoria Postdoctoral Research Fellowships to M.S. and H.L. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD