2,186 research outputs found
HIV-associated Cutaneous Dissemination of Visceral Leishmaniasis, Despite Negligible Immunodeficiency. Failure of Liposomal Amphotericin B Administration, Followed by Successful Pentamidine-Paromomycin Administration
and post hoc Tukey test. Statistical analysis of survival time was carried out with Kaplan-Meier (Log-Rank) test. Results: The immunized mice with this DNA vaccine presented an important reduction in diameter of lesion and increasing of weight compared to the control mice and was indicated a significant difference between the immunized group and the control groups (p < 0.05). The survival time of the immunized mice was significantly higher than the control groups (p < 0.05) after challenge with Leishmania major. The immunized mice had significantly lower parasite load compared to the control mice (p < 0.05). Conclusion: The findings of this study, indicated that the TSA encoded DNA vaccine induced protection against infection with Leishmania major in mice. In this study, we demonstrated that, the TSA -encoded DNA vaccine may be an excellent candidate for futher vaccine development
Multiscale entropy analysis of heart rate variability in neonatal patients with and without seizures
The complex physiological dynamics of neonatal seizures make their detection challenging. A timely diagnosis and treatment, especially in intensive care units, are essential for a better prognosis and the mitigation of possible adverse effects on the newborn’s neurodevelopment. In the literature, several electroencephalographic (EEG) studies have been proposed for a parametric characterization of seizures or their detection by artificial intelligence techniques. At the same time, other sources than EEG, such as electrocardiography, have been investigated to evaluate the possible impact of neonatal seizures on the cardio-regulatory system. Heart rate variability (HRV) analysis is attracting great interest as a valuable tool in newborns applications, especially where EEG technologies are not easily available. This study investigated whether multiscale HRV entropy indexes could detect abnormal heart rate dynamics in newborns with seizures, especially during ictal events. Furthermore, entropy measures were analyzed to discriminate between newborns with seizures and seizure-free ones. A cohort of 52 patients (33 with seizures) from the Helsinki University Hospital public dataset has been evaluated. Multiscale sample and fuzzy entropy showed significant differences between the two groups (p-value < 0.05, Bonferroni multiple-comparison post hoc correction). Moreover, interictal activity showed significant differences between seizure and seizure-free patients (Mann-Whitney Test: p-value < 0.05). Therefore, our findings suggest that HRV multiscale entropy analysis could be a valuable pre-screening tool for the timely detection of seizure events in newborns
Automatic Detection of Epileptic Seizures in Neonatal Intensive Care Units through EEG, ECG and Video Recordings: A Survey
In Neonatal Intensive Care Units (NICUs), the early detection of neonatal seizures is of utmost importance for a timely, effective and efficient clinical intervention. The continuous video electroencephalogram (v-EEG) is the gold standard for monitoring neonatal seizures, but it requires specialized equipment and expert staff available 24/24h. The purpose of this study is to present an overview of the main Neonatal Seizure Detection (NSD) systems developed during the last ten years that implement Artificial Intelligence techniques to detect and report the temporal occurrence of neonatal seizures. Expert systems based on the analysis of EEG, ECG and video recordings are investigated, and their usefulness as support tools for the medical staff in detecting and diagnosing neonatal seizures in NICUs is evaluated. EEG-based NSD systems show better performance than systems based on other signals. Recently ECG analysis, particularly the related HRV analysis, seems to be a promising marker of brain damage. Moreover, video analysis could be helpful to identify inconspicuous but pathological movements. This study highlights possible future developments of the NSD systems: a multimodal approach that exploits and combines the results of the EEG, ECG and video approaches and a system able to automatically characterize etiologies might provide additional support to clinicians in seizures diagnosis
Scintillator light yield measurements with waveform digitizers
The proton light yield of organic scintillators has been measured extensively
in recent years using fast waveform digitizers and large discrepancies exist in
the values reported by different authors. In this letter, we address principles
of digital signal processing that must be considered when conducting
scintillator light yield measurements. Digitized waveform pulse height values
are only proportional to the amount of scintillation light if the temporal
shape of the scintillation pulse is independent of the amount of energy
deposited. This is not the case for scintillation pulses resulting from fast
neutron interactions in organic scintillators. Authors measuring proton light
yield should therefore report pulse integral values and ensure that the
integration length is long enough to capture most of the scintillation light.Comment: 6 pages, 2 figure
Phase-space structures in quantum-plasma wave turbulence
The quasilinear theory of the Wigner-Poisson system in one spatial dimension
is examined. Conservation laws and properties of the stationary solutions are
determined. Quantum effects are shown to manifest themselves in transient
periodic oscillations of the averaged Wigner function in velocity space. The
quantum quasilinear theory is checked against numerical simulations of the
bump-on-tail and the two-stream instabilities. The predicted wavelength of the
oscillations in velocity space agrees well with the numerical results
Electrostatic pair creation and recombination in quantum plasmas
The collective production of electron-positron pairs by electrostatic waves
in quantum plasmas is investigated. In particular, a semi-classical governing
set of equation for a self-consistent treatment of pair creation by the
Schwinger mechanism in a quantum plasma is derived.Comment: 4 pages, 3 figures, to appear in JETP Letter
Nyquist method for Wigner-Poisson quantum plasmas
By means of the Nyquist method, we investigate the linear stability of
electrostatic waves in homogeneous equilibria of quantum plasmas described by
the Wigner-Poisson system. We show that, unlike the classical Vlasov-Poisson
system, the Wigner-Poisson case does not necessarily possess a Penrose
functional determining its linear stability properties. The Nyquist method is
then applied to a two-stream distribution, for which we obtain an exact,
necessary and sufficient condition for linear stability, as well as to a
bump-in-tail equilibrium.Comment: 6 figure
The Onset of Chaos with a Quadrupole--Quadrupole Interaction
The transition from order to chaos in atomic nuclei has been studied
analytically and numerically using a quadrupole--quadrupole residual
interaction. This interaction leads to chaotic behaviour, but the critical
energy MeV, corresponding to the onset of chaos, is higher
than that of the experimental one.Comment: 14 pages, 5 figures (available upon request to the authors), LaTex,
DFPD/93/TH/73, to be published in Nuovo Cimento
Two-Body Random Ensembles: From Nuclear Spectra to Random Polynomials
The two-body random ensemble (TBRE) for a many-body bosonic theory is mapped
to a problem of random polynomials on the unit interval. In this way one can
understand the predominance of 0+ ground states, and analytic expressions can
be derived for distributions of lowest eigenvalues, energy gaps, density of
states and so forth. Recently studied nuclear spectroscopic properties are
addressed.Comment: 8 pages, 4 figures. To appear in Physical Review Letter
Shielding of a moving test charge in a quantum plasma
The linearized potential of a moving test charge in a one-component fully
degenerate fermion plasma is studied using the Lindhard dielectric function.
The motion is found to greatly enhance the Friedel oscillations behind the
charge, especially for velocities larger than a half of the Fermi velocity, in
which case the asymptotic behavior of their amplitude changes from 1/r^3 to
1/r^2.5. In the absence of the quantum recoil (tunneling) the potential reduces
to a form similar to that in a classical Maxwellian plasma, with a difference
being that the plasma oscillations behind the charge at velocities larger than
the Fermi velocity are not Landau-damped.Comment: 9 pages, 11 figures. v3: Fixed typo, updated abstrac
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