27 research outputs found

    Recurrent madura foot without draining sinuses: a case report

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    Madura foot or mycetoma is a chronic granulomatous disease characterized by localized infection of subcutaneous tissues by actinomycetes or fungi. The recurrence rate for the disease if treated inadequately is very high. Recurrence presents with swelling and multiple discharging sinuses. This is an unusual presentation of the disease without discharging sinuses which is probable the first report of this kind in the literature. A 34 year old, male, presented with the painless, progressive swellings over right foot since 4 years. No sinuses or discharge could be found on skin surface. The postoperative recurrence rate is very high, and this can be local or distant at the regional lymph nodes. This could be due to the disease biology and behavior or inadequate surgical excision. Usually it presents with multiple sinus tracts, and granule. We reported a case with classical absence of sinus tracts in recurrent actinomycosis

    Kappa distribution from particle correlations in non-equilibrium, steady-state plasmas

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    Kappa-distributed velocities in plasmas are common in a wide variety of settings, from low-density to high-density plasmas. To date, they have been found mainly in space plasmas, but are recently being considered also in the modelling of laboratory plasmas. Despite being routinely employed, the origin of the kappa distribution remains, to this day, unclear. For instance, deviations from the Maxwell-Boltzmann distribution are sometimes regarded as a signature of the non-additivity of the thermodynamic entropy, although there are alternative frameworks such as superstatistics where such an assumption is not needed. In this work we recover the kappa distribution for particle velocities from the formalism of non-equilibrium steady-states, assuming only a single requirement on the dependence between the kinetic energy of a test particle and that of its immediate environment. Our results go beyond the standard derivation based on superstatistics, as we do not require any assumption about the existence of temperature or its statistical distribution, instead obtaining them from the requirement on kinetic energies. All of this suggests that this family of distributions may be more common than usually assumed, widening its domain of application in particular to the description of plasmas from fusion experiments. Furthermore, we show that a description of kappa-distributed plasma is simpler in terms of features of the superstatistical inverse temperature distribution rather than the traditional parameters κ\kappa and the thermal velocity vthv_{\text{th}}

    Use of a plasma focus device to study pulsed x-ray effects on peripheral blood lymphocytes : Analysis of chromosome aberrations

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    X-ray pulses (full width at half maximum ∼ 90 ns, dose rate ∼ 107 Gy s−1) were used to irradiate the monolayer of peripheral blood mononucleated cells using the PF-2kJ kilojoule plasma focus device. Four different exposure conditions were evaluated using 5, 10, 20, and 40 pulses, with the mean dose measured by TLD-100 being 0.12 ± 0.02 mGy, 0.14 ± 0.03 mGy, 0.22 ± 0.06 mGy, and 0.47 ± 0.09 mGy, respectively. Cytogenetic analysis showed an increase in all types of chromosomal aberrations following exposure to x-ray pulses. The distribution of dicentrics and centric rings was overdispersed after 5, 10, 20, and 40 pulses. Additionally, after 20 and 40 pulses, the presence of tricentric chromosomes is detected. Chromosome aberration frequencies found in this study were always higher than the estimated frequencies of chromosome aberrations using published dose-effect curves for conventional radiation sources. The overdispersion observed, the elevated maximum relative biological effectiveness (RBEM) and the presence of tricentric chromosomes at the relatively low doses of exposure (<0.5 Gy) seem to indicate that low doses of pulsed x-rays of low energy show similar biological effects as those observed for high-LET radiation. X-ray pulses emitted by PF-2kJ were found to be more efficient in inducing chromosome aberrations, even more than α particles

    Experimental measurements of high-energy photons in X-rays pulses emitted from a hundred joules plasma focus device and its interpretations

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    In the present work, efforts are made to identify the presence of high energy photons in X-rays pulses, emitted from a hundred joules plasma focus device, PF-400J. Two different experiments were carried out, with the insertion of a lead piece inside the hollow anode of PF-400J and without insertion of the lead piece. A pair of two photomultiplier tubes (PMTs) was mounted in the axial direction and a similar pair of PMTs was mounted in the radial direction, simultaneously. After establishing a correlation between two PMTs in each pair, one of the PMTs in both directions was blocked by a rectangular slab of the lead of thickness ~17 mm. Linear attenuation coefficient (LAC) of lead was estimated using the PMTs signals. Later, the X-rays energies were interpolated for the estimated LAC values in both cases, with and without insertion of lead piece inside the hollow anode. Interpolated energies reveal the presence of 0.55–0.85 MeV photons in the X-rays pulses in the axial direction, while, in radial direction ranges 0.4–0.9 MeV, for the case without lead inserted inside the hollow anode. Insertion of the lead inside the hollow anode does not change the X-rays energies significantly, nonetheless, it increases X-rays repetition rate per hundred discharges. The presence of high energy photons in the X-rays pulses indicates the existence of relativistic electrons. To explain it, induced electric and magnetic fields were estimated using generalized Ohm’s law. We conclude that the electron acceleration mechanisms might not be the same in the axial and radial directions.Indexación: Scopu

    Implications of Superstatistics for steady-state plasmas

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    Colissionless plasmas are non-extensive systems which, due to the long-range interaction between their components, are incapable of reaching thermal equilibrium, even in a steady state. These systems cannot, therefore, be described statistically by a single canonical distribution with well-defined inverse temperature β = 1/kBT and are commonly described via two alternative approaches: namely Tsallis statistics and Superstatistics. The use of Superstatistics in describing steady-state plasmas has been proposed by several authors, more recently Ourabah et al. In this work we study the consequences of this assumption of Superstatistics for steady-state plasmas. We explicitly show that only the ensembles characterized by the condition P(x|ρ) = ρ(H(x)) are consistent with a generalized definition of temperature introduced recently. We show how this formalism is employed in the case of plasma, considering interaction with external electromagnetic fields as well as between particles in the plasma. Our results clearly illustrate why low-energy particles tend to the Maxwellian distribution of velocities, while high-energy particles contribute to the long tails of the velocity distribution
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