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Publicatii proprii
Horizon Wave-Function and the Quantum Cosmic Censorship
We investigate the Cosmic Censorship Conjecture by means of the horizon wave-function (HWF) formalism. We consider a charged massive particle whose quantum mechanical state is represented by a spherically symmetric Gaussian wave-function, and restrict our attention to the superxtremal case (with charge-to-mass ratio a > 1), which is the prototype of a naked singularity in the classical theory. We find that one can still obtain a normalisable HWF
Read moreInner Horizon of the Quantum Reissner-Nordström Black Holes
We study the nature of the inner Cauchy horizon of a Reissner-Nordström black hole in a quantum context by means of the horizon wave-function obtained from modelling the electrically charged source as a Gaussian wave-function. Our main finding is that there are significant ranges for the black hole mass (around the Planck scale) and specific charge for which the probability of realising the inner horizon is negligible. This result suggests that
Read moreControl point based exact description of trigonometric/hyperbolic curves, surfaces and volumes
Using the normalized B-bases of vector spaces of trigonometric and hyperbolic polynomials of finite order, we specify control point configurations for the exact description of the zeroth and higher order (mixed partial) derivatives of integral curves and (hybrid) multivariate surfaces determined by coordinate functions that are exclusively given either by traditional trigonometric or hyperbolic polynomials in each of their variables. Based on homogeneous
Read moreEmbanking the Lower Danube: From Natural to Engineered Floodplains and Back
Anthropogenic intervention along the Danube floodplain has occurred in various degrees since ancient times. Early in this history, small and localized changes were linked to fishing as floodplain lakes and channels constituted a permanent and trusted source of fish. Large-scale, intense changes occurred primarily during the communist period when most of the floodplain was used for agriculture. As a result of this phase, 3250 km of artificial levee
Read moreWhat makes a delta wave-dominated?
River deltas, low-lying landforms that host high concentrations of human population and ecosystem services, face a new, and mostly unknown, future over the coming decades and centuries. Even as some deltas experience decreased sediment supply from damming, others will see increased sediment discharge from land-use changes. There are proposals to actively use riverine sediment supply to build new land and counteract delta loss. We present a novel
Read moreIntercellular communication by extracellular vesicles with emphasis on the roles of cordocytes in the human brain. An ultrastructural study
We describe in this work the presence of extracellular vesicles (EVs) along different cell types, especially cordocytes, in various clinical conditions of the human brain (atherothrombotic disease, cerebral tumors, hygroma durae matris, intracerebral cysts, Moyamoya disease and parenchymatous hematoma) using transmission electron microscopy (TEM). EVs, illustrated as exosomes and microvesicles, were causally related to cell-to-cell communication,
Read moreEnantioselective stable isotope analysis (ESIA) — A new concept to evaluate the environmental fate of chiral organic contaminants
Since 2011, the enantiospecific stable carbon isotope analysis (ESIA) has emerged as an innovative technique to assess the environmental fate of chiral emerging compounds by combining in one experimental technique both compound specific isotope analysis (CSIA) and enantioselective analysis. To date, the ESIA was applied for four classes of compounds: α-hexachlorocyclohexane (α-HCH), polar herbicides (phenoxy acids), synthetic polycyclic musk galaxolide
Read moreEddy Current Levitation in Ferromagnetic Structures
The efficiency of electromagnetic levitation devices can be improved by shortening the path of the magnetic flux which can be done by employing a magnetic circuit. The eddy currents are computed using an integral equation, and the ferromagnetic materials nonlinearity is treated by applying the polarization fixed point iterative method, with a dynamic overrelaxation technique. To substantially reduce the computation time, the eddy current integral
Read moreRadio monitoring of the hard state jets in the 2011 outburst of MAXI J1836-194
MAXI J1836-194 is a Galactic black hole candidate X-ray binary that was discovered in 2011 when it went into outburst. In this paper, we present the full radio monitoring of this system during its "failed" outburst, in which the source did not complete a full set of state changes, only transitioning as far as the hard intermediate state. Observations with the Karl G. Jansky Very Large Array (VLA) and Australia Telescope Compact Array (ATCA) show
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