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Is it plausible to expect a close encounter of the Earth with a yet undiscovered astronomical object in the next few years?  [PDF]
Lorenzo Iorio
Natural Science (NS) , 2010, DOI: 10.4236/ns.2010.211146
Abstract: We analytically and numerically investigate the possibility that a still undiscovered body X, moving along an unbound hyperbolic path from outside the solar system, may penetrate its inner regions in the next few years posing a threat to the Earth. By conservatively using as initial position of X the lower bounds on the present‐day distance of X dynamically inferred from the gravitational perturbations induced by it on the orbital motions of the planets of the solar system, both the analyses show that, in order to reach the Earth’s orbit in the next 2 yr, X should move at a highly unrealistic speed , whatever its mass is. For example, by assuming for it a solar ( M ) or brown dwarf mass ( ), now at not less than kau (1 kau=1000 astronomical units), v would be of the order of and of the speed of light c, respectively. By assuming larger present‐day distances for X, on the basis of the lacking of direct observational evidences of electromagnetic origin for it, its speed would be even higher. Instead, the fastest solitary massive objects known so far, like hypervelocity stars (HVSs) and supernova remnants (SRs), travel at , having acquired so huge velocities in some of the most violent astrophysical phenomena like interactions with supermassive galactic black holes and supernova explosions. It turns out that the orbit of the Earth would not be macroscopically altered by a close (0.2 au) passage of such an ultrafast body X in the next 2 yr. On the contrary, our planet would be hurled into the space if a Sun‐sized body X would encounter it by moving at . On the other hand, this would imply that such a X should be now at just 20-30 au, contrary to all direct observational and indirect dynamical evidences.
On Some Critical Issues of the LAGEOS-Based Tests of the Lense-Thirring Effect  [PDF]
Lorenzo Iorio
Journal of Modern Physics (JMP) , 2011, DOI: 10.4236/jmp.2011.24029
Abstract: We summarize some critical issues pertaining the tests of the general relativistic Lense-Thirring effect performed by I. Ciufolini and coworkers in the gravitational field of the Earth with the geodetic satellites LAGEOS and LAGEOS II tracked with the Satellite Laser Ranging technique.
On Possible A-Priori “Imprinting” of General Relativity Itself on the Performed Lense-Thirring Tests with LAGEOS Satellites  [PDF]
Lorenzo Iorio
Communications and Network (CN) , 2010, DOI: 10.4236/cn.2010.21003
Abstract: The impact of possible a-priori “imprinting” effects of general relativity itself on recent attempts to measure the general relativistic Lense-Thirring effect with the LAGEOS satellites orbiting the Earth and the terrestrial geopotential models from the dedicated mission GRACE is investigated. It is analytically shown that general relativity, not explicitly solved for in the GRACE-based models, may “imprint” their even zonal harmonic coeffi-cients of low degrees at a non-negligible level, given the present-day accuracy in recovering them. This trans-lates into a bias of the LAGEOS-based relativistic tests as large as the Lense-Thirring effect itself. Further analyses should include general relativity itself in the GRACE data processing by explicitly solving for it.
Orbital effects of Sun’s mass loss and the Earth’s fate  [PDF]
Lorenzo Iorio
Natural Science (NS) , 2010, DOI: 10.4236/ns.2010.24041
Abstract: I calculate the classical effects induced by an isotropic mass loss of a body on the orbital motion of a test particle around it; the present analysis is also valid for a variation of the Newtonian constant of gravitation. I perturbatively obtain negative secular rates for the osculating semimajor axis a, the eccentricity e and the mean anomaly , while the argument of pericenter ω does not undergo secular precession, like the longitude of the ascending node Ω and the inclination I. The anomalistic period is different from the Keplerian one, being larger than it. The true orbit, instead, expands, as shown by a numerical integration of the equations of motion in Cartesian coordinates; in fact, this is in agreement with the seemingly counter-intuitive decreasing of a and e because they only refer to the osculating Keplerian ellipses which approximate the trajectory at each instant. By assuming for the Sun it turns out that the Earth's perihelion position is displaced outward by 1.3 cm along the fixed line of apsides after each revolution. By applying our results to the phase in which the radius of the Sun, already moved to the Red Giant Branch of the Hertzsprung-Russell Diagram, will become as large as 1.20 AU in about 1 Myr, I find that the Earth's perihelion position on the fixed line of the apsides will increase by AU (for ); other researchers point towards an increase of AU. Mercury will be destroyed already at the end of the Main Sequence, while Venus should be engulfed in the initial phase of the Red Giant Branch phase; the orbits of the outer planets will increase by AU. Simultaneous long-term numerical integrations of the equations of motion of all the major bodies of the solar system, with the inclusion of a mass-loss term in the dynamical force models as well, are required to check if the mutual N-body interactions may substantially change the picture analytically outlined here, especially in the Red Giant Branch phase in which Mercury and Venus may be removed from the integration.
The Relativistic Three-Dimensional Evolution of SN 1987A  [PDF]
Lorenzo Zaninetti
International Journal of Astronomy and Astrophysics (IJAA) , 2014, DOI: 10.4236/ijaa.2014.42030
Abstract:

The high velocities observed in supernovae require a relativistic treatment for the equation of motion in the presence of gradients in the density of the interstellar medium. The adopted theory is that of the thin layer approximation. The chosen medium is auto-gravitating with respect to an equatorial plane. The differential equation which governs the relativistic conservation of momentum is solved numerically and by recursion. The asymmetric field of relativistic velocities as well the time dilation is plotted at the age of 1 yr for SN 1987A.

Classical and Relativistic Flux of Energy Conservation in Astrophysical Jets  [PDF]
Lorenzo Zaninetti
Journal of High Energy Physics, Gravitation and Cosmology (JHEPGC) , 2016, DOI: 10.4236/jhepgc.2016.21005
Abstract: The conservation of the energy flux in turbulent jets which propagate in the intergalactic medium (IGM) allows deducing the law of motion in the classical and relativistic cases. Three types of IGM are considered: constant density, hyperbolic and inverse power law decrease of density. An analytical law for the evolution of the magnetic field along the radio-jets is deduced using a linear relation between the magnetic pressure and the rest density. Astrophysical applications are made to the centerline intensity of synchrotron emission in NGC315 and to the magnetic field of 3C273.
Financial Innovation, Macroeconomic Volatility and the Great Moderation  [PDF]
Lorenzo Bencivelli, Andrea Zaghini
Modern Economy (ME) , 2012, DOI: 10.4236/me.2012.35071
Abstract: In the paper we propose an assessment of the role of financial innovation in shaping US macroeconomic dynamics. We extend an existing model by Christiano, Eichenbaum and Evans which studied the transmission of monetary policy im- pulses to business and corporate sector financing variables just before the Great Moderation period. By investigating the properties of the model over a longer time span we show that in the later period a change in the monetary policy trans- mission mechanism is likely to have occurred. In particular, we argue that the role of financial innovation has signify- cantly altered the transmission of shocks.
The Machian Origin of the Centrifugal Force  [PDF]
Lorenzo Barattini, Paolo Christillin
Journal of Modern Physics (JMP) , 2012, DOI: 10.4236/jmp.2012.329167
Abstract: A derivation of the centrifugal force from an effective vector formulation of gravitation is attempted. The centrifugal force appears to be due to a relativistic effect of the counter-rotating Universe. Gravitomagnetic energy effects, a mil-lion times stronger than the self-energy effects responsible for curvature in the GR language, would thus produce the centrifugal acceleration. The Machian picture, already successful in the case of the Coriolis force, gets an additional circumstantial support.
The Interventions of Pietro da Cortona in the Crypt of Santa Maria in Via Lata in Rome, Studied through a Morphometric Three-Dimensional Survey  [PDF]
Lorenzo Pio Massimo Martino
Open Journal of Civil Engineering (OJCE) , 2014, DOI: 10.4236/ojce.2014.42009
Abstract:

Twenty years after the last archaeological researches and surveys, a new investigation has been carried out on the basement in the church of Santa Maria in Via Lata in Rome. The study has employed three-dimensional surveys with laser scanning methodology and has focused both on archaeological and architectural issues. Indeed, the present layout of the basement derives from a XVII century remodelling of early Christian and medieval spaces planned by Pietro da Cortona. The architect gave a unique setting and composition to the underground spaces, different in shapes and building materials, thanks to the refinement of his baroque language. Though he worked in small spaces with static problems connected to the foundations and to the loads of the church rising above, and with poor lighting and extreme dampness, Pietro da Cortona put skilfully together “modern” elements with ancient or historical pre-existences. The study focuses on Berrettini’s design process through a three-dimensional analysis with CAD systems, starting from the new XVII century fa?ade and from the articulated distribution of routes that led to the intimate underground interiors. Metrical processing gave the possibility to improve the knowledge about room geometry and to confirm the interpretations put forward by major scholars such as Krautheimer and Cavazzi.

Neural Modulation of Hemiparetic Shoulder Pain by Repetitive Ultrasound-Guided Suprascapularis Nerve Block  [PDF]
Luigi Di Lorenzo,Santopadre Domenico
Open Journal of Anesthesiology (OJAnes) , 2013, DOI: 10.4236/ojanes.2013.33030
Abstract: Background: Neural blockade is widely used in clinical practice to alleviate acute or chronic pain, including pain during rehabilitation. To date there is little controlled evidence to confirm the efficacy of nerve blocks in hemiparetic shoulder pain after stroke. Design: This study is a prospective, open label, cohort trial reporting result from a cohort of stroke patients affected by shoulder pain. Aim: As a cohort study report, in which it is often firstly reported the possibility of an association between an observed effect and a specific environmental based on detailed clinical evaluations and histories, we aim to firstly provide clues in identifying Suprascapularis Nerve blockade as further valuable approach for shoulder pain after stroke. Population: We studied a cohort of patients affected by hemiparetic shoulder pain after Stroke. Methods: Our protocol foresees nerve blocks to be performed each 3 out of 4 days (treatment lasting 30 days) in conjunction with a rehabilitation program with the first aim to provide the window of opportunity to proceed with effective rehabilitation. 47 potential study subjects fulfilled the study criteria and were enrolled. Twenty-four subjects were randomised to the study Group to receive SSNB for the pain of their hemiparetic shoulder while 23 subjects randomized to the control Group whose member did not receive SSNB. They received serial blocks each 3 out of 4 days during rehabilitation.Results: Both treatment reported a reduction in the intensity of their shoulder pain, according to data collected from day 1 through day 42 (6 weeks). Study Group patients, receiving SSNBs, reported significant improvement from entry through the whole follow-up period. The efficiency data were higher for SSNB Group after 2 weeks and again for SSNb group at the end of treatment. Conclusion: Excellent pain relief was achieved in SSNB without clinically relevant complications, these patients having a better improvement on pain during rehabilitation, than the control subjects. Great efficacy has been achieved by combining a nerve block and rehabilitation. About Clinical Rehabilitation Impact, we believe that Suprascapularis nerve blocks can help the stroke survivors maintain an ambulatory or outpatient treatment status, maintain participation in a physical therapy or rehabilitation program, decrease the need for analgesics and in some cases lead to a complete pain relief.
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