448 research outputs found

    Super Calabi-Yau's and Special Lagrangians

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    We apply mirror symmetry to the super Calabi-Yau manifold CP^{(n|n+1)} and show that the mirror can be recast in a form which depends only on the superdimension and which is reminiscent of a generalized conifold. We discuss its geometrical properties in comparison to the familiar conifold geometry. In the second part of the paper examples of special-Lagrangian submanifolds are constructed for a class of super Calabi-Yau's. We finally comment on their infinitesimal deformations.Comment: 20 pages, no figures, latex; v2: references added; v3: minor clarifications added, version published in JHE

    Ergonomics and sustainability: Towards and embrace of complexity and emergence

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    Technology offers a promising route to a sustainable future, and ergonomics can serve a vital role. The argument of this article is that the lasting success of sustainability initiatives in ergonomics hinges on an examination of ergonomics' own epistemology and ethics. The epistemology of ergonomics is fundamentally empiricist and positivist. This places practical constraints on its ability to address important issues such as sustainability, emergence and complexity. The implicit ethical position of ergonomics is one of neutrality, and its positivist epistemology generally puts value-laden questions outside the parameters of what it sees as scientific practice. We argue, by contrast, that a discipline that deals with both technology and human beings cannot avoid engaging with questions of complexity and emergence and seeking innovative ways of addressing these issues.No Full Tex

    Expression of CD45RC and Ia Antigen in the Spinal Cord in Acute Experimental Allergic Encephalomyelitis: An Immunocytochemical and Flow Cytometric Study

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    We performed immunocytochemical studies to analyze the inflammatory infiltrate and major histocompatibility complex class II (Ia) antigen expression in the spinal cord of Lewis rats with acute experimental allergic encephalomyelitis (EAE) induced by inoculation with myelin basic protein and adjuvants. Using antibodies to lymphocyte markers and other monoclonal antibodies we found that during clinical episodes the inflammatory infiltrate was chiefly composed of T lymphocytes and macrophages. The majority of cells in the inflammatory infiltrate were stained by the W3/25 antibody to CD4 and a proportion was stained by OX22 which labels the high molecular weight form of the leucocyte common antigen (CD45RC). CDB+ T cells were sparse and B cells were not detected. There was minimal staining with the OX39 antibody to the interleukin-2 receptor. Presumptive microglia, identified by their dendritic morphology, expressed Ia antigen during the clinical episodes and after recovery. The prominence of Ia antigen expression after recovery could indicate that this la expression was associated with downregulation of the encephalitogenic immune response. We also performed flow cytometry studies on cells extracted from the spinal cord of rats before and during attacks of EAE. With flow cytometry, we found that in established disease a mean of 83(SD, 23)% of CD2+ cells were CD4+, and a mean of 27(SD, 12)% of CD2+ cells were CD45RC+. In rats sampled on the first day of signs, a mean of 43(SD, 22)% of CD2+ cells were CD45RC+. In the cells extracted from the spinal cord of rats with established disease a mean of 47(SD, 32)% of macrophages were CD45RC+. Our study has combined an immunocytochemical assessment of tissue sections with quantitative flow cytometry assessment of cells extracted from the spinal cord of rats with acute EAE. We have shown that the majority of T lymphocytes in the spinal cord are CD45RC-. We have also found prominent Ia expression on dendritic cells in acute EAE and after clinical recovery

    A Conformally Invariant Holographic Two-Point Function on the Berger Sphere

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    We apply our previous work on Green's functions for the four-dimensional quaternionic Taub-NUT manifold to obtain a scalar two-point function on the homogeneously squashed three-sphere (otherwise known as the Berger sphere), which lies at its conformal infinity. Using basic notions from conformal geometry and the theory of boundary value problems, in particular the Dirichlet-to-Robin operator, we establish that our two-point correlation function is conformally invariant and corresponds to a boundary operator of conformal dimension one. It is plausible that the methods we use could have more general applications in an AdS/CFT context.Comment: 1+49 pages, no figures. v2: Several typos correcte

    Computing Amplitudes in topological M-theory

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    We define a topological quantum membrane theory on a seven dimensional manifold of G2G_2 holonomy. We describe in detail the path integral evaluation for membrane geometries given by circle bundles over Riemann surfaces. We show that when the target space is CY3×S1CY_3\times S^1 quantum amplitudes of non-local observables of membranes wrapping the circle reduce to the A-model amplitudes. In particular for genus zero we show that our model computes the Gopakumar-Vafa invariants. Moreover, for membranes wrapping calibrated homology spheres in the CY3CY_3, we find that the amplitudes of our model are related to Joyce invariants.Comment: 26 page

    The relationship between body mass index and sleep in women with risk factors for gestational diabetes mellitus

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    OnlinePublBackground: Both obesity and sleep disorders are common among women during pregnancy. Although prior research has identified a relationship between obesity and sleep disorders, those findings are from women later in pregnancy. Objective: To explore the relationships between self‐reported sleep duration, insufficient sleep and snoring with body mass index (BMI) among multiethnic women at risk of gestational diabetes mellitus (GDM)in early pregnancy.Methods: Cross‐sectional study of baseline data from women at risk of GDM enrolled in the Treatment of BOoking Gestational diabetes Mellitus (TOBOGM) multicentre trial across 12 Australian/Austrian sites. Participants completed a questionnaire before 20 weeks’ gestation to evaluate sleep. BMI 5 days/ month was higher in class II and class III obesity (1.38 (1.03–1.85) and 1.34 (1.01– 1.80), respectively), and the risk of snoring increased as BMI increased (1.59 (1.25– 2.02), 2.68 (2.07–3.48), 4.35 (3.21–5.88) to 4.96 (3.65–6.74), respectively)). Conclusions: Obesity is associated with insufficient sleep among pregnant women at risk of GDM. Snoring is more prevalent with increasing BMI.Pamela Acosta Reyes, Jincy Immanuel, William M. Hague, Helena Teede, Emily Hibbert, Christopher J. Nolan, Michael J. Peek, Vincent Wong, Jeffrey R. Flack, Mark McLean, Raiyomand Dalal, Jürgen Harreiter, Alexandra Kautzky, Willer, Rohit Rajagopal, Arianne Sweeting, Glynis P. Ross, Ngai Wah Cheung, David Simmon

    The Warnie volcanic province : Jurassic intraplate volcanism in Central Australia

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    We wish to thank Santos Ltd. for providing us with the Snowball 3D seismic survey. In particular we wish to thank Jenni Clifford and Lance Holmes who provided helpful feedback and 2D seismic lines covering the Lambda 1, Orientos 2 and Warnie East 1 wells. We also wish to thank Beach Energy, in particular Rob Menpes, for the helpful discussions and feedback on the manuscript in addition to helping us with the analysis of the magnetic data. The work contained in this paper contains work conducted during a PhD study undertaken as part of the Natural Environment Research Council (NERC) Centre for Doctoral Training (CDT) in Oil & Gas [grant number NEM00578X/1] and is fully funded by NERC whose support is gratefully acknowledged. Lastly, the two anonymous reviews of the manuscript are thanked for their insightful and constructive comments that significantly improved the work presented.Peer reviewedPostprin

    El Apego Va a Juicio: Problemas de Custodia y Protección Infantil1

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    Attachment theory and research are drawn upon in many applied settings, including family courts, but misunderstandings are widespread and sometimes result in misapplications. The aim of this consensus statement is, therefore, to enhance understanding, counter misinformation, and steer family-court utilisation of attachment theory in a supportive, evidence-based direction, especially with regard to child protection and child custody decision-making. This article is divided into two parts. In the first part, we address problems related to the use of attachment theory and research in family courts, and discuss reasons for these problems. To this end, we examine family court applications of attachment theory in the current context of the best-interest-of-the-child standard, discuss misunderstandings regarding attachment theory, and identify factors that have hindered accurate implementation. In the second part, we provide recommendations for the application of attachment theory and research. To this end, we set out three attachment principles: the child’s need for familiar, non-abusive caregivers; the value of continuity of good-enough care; and the benefits of networks of attachment relationships. We also discuss the suitability of assessments of attachment quality and caregiving behaviour to inform family court decision-making. We conclude that assessments of caregiver behaviour should take center stage. Although there is dissensus among us regarding the use of assessments of attachment quality to inform child custody and child-protection decisions, such assessments are currently most suitable for targeting and directing supportive interventions. Finally, we provide directions to guide future interdisciplinary research collaboration

    Association of genetic susceptibility variants for type 2 diabetes with breast cancer risk in women of European ancestry.

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    Purpose: Type 2 diabetes (T2D) has been reported to be associated with an elevated risk of breast cancer. It is unclear, however, whether this association is due to shared genetic factors. Methods: We constructed a genetic risk score (GRS) using risk variants from 33 known independent T2D susceptibility loci and evaluated its relation to breast cancer risk using the data from two consortia, including 62,328 breast cancer patients and 83,817 controls of European ancestry. Unconditional logistic regression models were used to derive adjusted odds ratios (ORs) and 95 % confidence intervals (CIs) to measure the association of breast cancer risk with T2D GRS or T2D-associated genetic risk variants. Meta-analyses were conducted to obtain summary ORs across all studies. Results: The T2D GRS was not found to be associated with breast cancer risk, overall, by menopausal status, or for estrogen receptor positive or negative breast cancer. Three T2D associated risk variants were individually associated with breast cancer risk after adjustment for multiple comparisons using the Bonferroni method (at p < 0.001), rs9939609 (FTO) (OR 0.94, 95 % CI = 0.92–0.95, p = 4.13E−13), rs7903146 (TCF7L2) (OR 1.04, 95 % CI = 1.02–1.06, p = 1.26E−05), and rs8042680 (PRC1) (OR 0.97, 95 % CI = 0.95–0.99, p = 8.05E−04). Conclusions: We have shown that several genetic risk variants were associated with the risk of both T2D and breast cancer. However, overall genetic susceptibility to T2D may not be related to breast cancer risk

    Transitions of cardio-metabolic risk factors in the Americas between 1980 and 2014

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    Describing the prevalence and trends of cardiometabolic risk factors that are associated with non-communicable diseases (NCDs) is crucial for monitoring progress, planning prevention, and providing evidence to support policy efforts. We aimed to analyse the transition in body-mass index (BMI), obesity, blood pressure, raised blood pressure, and diabetes in the Americas, between 1980 and 2014
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