140 research outputs found

    Congenital Lymphoedema, Bronchiectasis And Seizure: Case Report

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    A l0-year-old girl with facial anomalies, mental retardation, peripheral lymphoedema, convulsions, cerebral cortical dysgenetic changes, bronchiectasis and chronic sinusitis is presented. She had features of both yellow nail syndrome and Hennekam syndrome. We think that our case might be a new congenital lymphoedema syndrome or an intermediate form between these syndromes. East African Medical Journal Vol. 85 (3) 2008: pp. 145-14

    Dyonic Kerr-Newman black holes, complex scalar field and Cosmic Censorship

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    We construct a gedanken experiment, in which a weak wave packet of the complex massive scalar field interacts with a four-parameter (mass, angular momentum, electric and magnetic charges) Kerr-Newman black hole. We show that this interaction cannot convert an extreme the black hole into a naked sigularity for any black hole parameters and any generic wave packet configuration. The analysis therefore provides support for the weak cosmic censorship conjecture.Comment: Refined emphasis on the weak cosmic censorship conjecture, conclusions otherwise unchanged. Also, two sections merged, literature review updated, references added, a few typos correcte

    On the exactness of the Semi-Classical Approximation for Non-Relativistic One Dimensional Propagators

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    For one dimensional non-relativistic quantum mechanical problems, we investigate the conditions for all the position dependence of the propagator to be in its phase, that is, the semi-classical approximation to be exact. For velocity independent potentials we find that: (i) the potential must be quadratic in space, but can have arbitrary time dependence. (ii) the phase may be made proportional to the classical action, and the magnitude (``fluctuation factor'') can also be found from the classical solution. (iii) for the driven harmonic oscillator the fluctuation factor is independent of the driving term.Comment: 7 pages, latex, no figures, published in journal of physics

    Destroying black holes with test bodies

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    If a black hole can accrete a body whose spin or charge would send the black hole parameters over the extremal limit, then a naked singularity would presumably form, in violation of the cosmic censorship conjecture. We review some previous results on testing cosmic censorship in this way using the test body approximation, focusing mostly on the case of neutral black holes. Under certain conditions a black hole can indeed be over-spun or over-charged in this approximation, hence radiative and self-force effects must be taken into account to further test cosmic censorship.Comment: Contribution to the proceedings of the First Mediterranean Conference on Classical and Quantum Gravity (talk given by T. P. S.). Summarizes the results of Phys. Rev. Lett. 103, 141101 (2009), arXiv:0907.4146 [gr-qc] and considers further example

    The Dirac Equation Is Separable On The Dyon Black Hole Metric

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    Using the tetrad formalism, we carry out the separation of variables for the massive complex Dirac equation in the gravitational and electromagnetic field of a four-parameter (mass, angular momentum, electric and magnetic charges) black hole.Comment: 13 page

    Assessment of subjective sleep quality in iron deficiency anaemia

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    Objectives: We aimed to assess the effect of anemia on subjective sleep quality in patients with iron deficiency anemia (IDA).Methods: One hundred and four patients diagnosed with IDA and 80 healthy individuals, who are gender and age matched, were included in the study. All participants were requested to fill 3 forms: a socio-demographic form (age, gender, marital status, income level and educational status), hospital anxiety and depression (HAD) scale and pittsburgh sleep quality index (PSQI).Results: According to the HAD scale, the average anxiety score was found 9.24±4.37 in patients and 7.58± 4.07 in controls. And, the average depression score was 7.53±4.10 in patients and 6.41±2.74 in controls. The total sleep quality score was 6.71±3.02 in patients and 4.11±1.64 in controls. There was a statistically significant difference in terms of anxiety, depression and sleep quality scores. Linear regression analysis showed no association between anxiety and depression with poor sleeping.Conclusion: IDA affects sleep quality irrespective of psychological symptoms such as depression and anxiety.Keywords: Iron deficiency anemia, sleep quality, anxiet

    Overcharging a Black Hole and Cosmic Censorship

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    We show that, contrary to a widespread belief, one can overcharge a near extremal Reissner-Nordstrom black hole by throwing in a charged particle, as long as the backreaction effects may be considered negligible. Furthermore, we find that we can make the particle's classical radius, mass, and charge, as well as the relative size of the backreaction terms arbitrarily small, by adjusting the parameters corresponding to the particle appropriately. This suggests that the question of cosmic censorship is still not wholly resolved even in this simple scenario. We contrast this with attempting to overcharge a black hole with a charged imploding shell, where we find that cosmic censorship is upheld. We also briefly comment on a number of possible extensions.Comment: 26 pages, 3 figures, LaTe
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