11,659 research outputs found

    Quaternionic Hyperbolic Function Theory

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    We are studying hyperbolic function theory in the skew-field of quaternions. This theory is connected to k-hyperbolic harmonic functions that are harmonic with respect to the hyperbolic Riemannian metric (Formula Presented) in the upper half space (Formula Presented). In the case k = 2, the metric is the hyperbolic metric of the Poincaré upper half-space. Hempfling and Leutwiler started to study this case and noticed that the quaternionic power function xm(m ε Z), is a conjugate gradient of a 2-hyperbolic harmonic function. They researched polynomial solutions. We find fundamental k-hyperbolic harmonic functions depending only on the hyperbolic distance and x3. Using these functions we are able to verify a Cauchy type integral formula. Earlier these results have been verified for quaternionic functions depending only on reduced variables (x0, x1, x2). Our functions are depending on four variables. © Springer Nature Switzerland AG 2019.Peer reviewe

    Conserved Matter Superenergy Currents for Orthogonally Transitive Abelian G2 Isometry Groups

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    In a previous paper we showed that the electromagnetic superenergy tensor, the Chevreton tensor, gives rise to a conserved current when there is a hypersurface orthogonal Killing vector present. In addition, the current is proportional to the Killing vector. The aim of this paper is to extend this result to the case when we have a two-parameter Abelian isometry group that acts orthogonally transitive on non-null surfaces. It is shown that for four-dimensional Einstein-Maxwell theory with a source-free electromagnetic field, the corresponding superenergy currents lie in the orbits of the group and are conserved. A similar result is also shown to hold for the trace of the Chevreton tensor and for the Bach tensor, and also in Einstein-Klein-Gordon theory for the superenergy of the scalar field. This links up well with the fact that the Bel tensor has these properties and the possibility of constructing conserved mixed currents between the gravitational field and the matter fields.Comment: 15 page

    Experimental f-value and isotopic structure for the Ni I line blended with [OI] at 6300A

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    We have measured the oscillator strength of the Ni I line at 6300.34 \AA, which is known to be blended with the forbidden [O I] λ\lambda6300 line, used for determination of the oxygen abundance in cool stars. We give also wavelengths of the two isotopic line components of 58^{58}Ni and 60^{60}Ni derived from the asymmetric laboratory line profile. These two line components of Ni I have to be considered when calculating a line profile of the 6300 \AA\ feature observed in stellar and solar spectra. We also discuss the labelling of the energy levels involved in the Ni I line, as level mixing makes the theoretical predictions uncertain.Comment: Accepted for publication in ApJLetter

    Intimate Femicide: The Role of Coercive Control

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    Severe and escalating violence is cited as a precursor to intimate partner homicide and figures prominently in risk assessments and domestic violence death reviews. Drawing on interviews from the Australian Homicide Project with a sample of men convicted of killing intimate partners, we examine the backgrounds of perpetrators and the contexts in which the killings occurred and find that fully half report no physical or sexual assaults against their partners in the year prior to the homicide. These results raise important questions about assessments of risk and the typification of the “battered woman” on which many policy responses rely

    Serum TK1 protein and C-reactive protein correlate to treatment response and predict survival in dogs with hematologic malignancies

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    Thymidine kinase 1 (TK1), involved in DNA precursor synthesis, is used as a serum biomarker in cancer diagnostics in both human and veterinary medicine. We investigated the utility of serum TK1 protein (TK1p) and TK1 activity (TK1a) determinations for prognosis and monitoring of canine hematological malignancies. The combination of TK1p or TK1a with canine C-reactive protein (CRP) determinations was also investigated. Serum samples from 51 client-owned dogs with naive hematological malignancies and from 149 healthy subjects were included. Serum TK1p levels were determined using a prototype TK1-ELISA, TK1a using the [H-3]- dThd phosphorylation assay, and CRP using an immunoturbidimetric assay. Mean TK1p in sera from dogs with tumors was significantly higher than from healthy dogs (mean +/- SD = 3.9 +/- 5.9 vs. 0.45 +/- 0.15 ng/mL). Similarly, TK1a in hematological malignancies was significantly higher than in healthy dogs (mean + SD = 15.1 +/- 31.3 vs. 0.96 +/- 0.33 pmol/min/mL). The receiver-operating characteristic indicated that a combination of TK1p or TK1a with CRP gave higher sensitivity than either biomarker alone for the prognosis of hematological malignancies. Median pretreatment TK1p and TK1a levels were significantly higher than in dogs in remission and correlated with clinical outcome. Kaplan-Meier curve analysis showed that naive dogs with high TK1p, TK1a, and CRP had significantly shorter survival. This study present two new polyclonal antibodies used in an ELISA system to determine TK1p. The study also show that combining TK1p or TK1a with CRP gave higher sensitivity than either biomarker alone. Monitoring patients in the study while undergoing chemotherapy, suggests that the TK1 + CRP combination could be useful in a biomarker panel, possibly aiding the prognosis and therapy monitoring of hematological malignancies in dogs.Peer reviewe
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