Reconnecting groups of space debris to their parent body through proper elements

Satellite collisions or fragmentations generate a huge number of space debris; over time, the fragments might get dispersed, making it difficult to associate them to the configuration at break-up. In this work, we present a procedure to back-trace the debris, reconnecting them to their original configuration. To this end, we compute the proper elements, namely dynamical quantities which stay nearly constant over time. While the osculating elements might spread and lose connection with the values at break-up, the proper elements, which have been already successfully used to identify asteroid families, retain the dynamical features of the original configuration. We show the efficacy of the procedure, based on a hierarchical implementation of perturbation theory, by analyzing the following four different case studies associated to satellites that underwent a catastrophic event: Ariane 44lp, Atlas V Centaur, CZ-3, Titan IIIc Transtage. The link between (initial and final) osculating and proper elements is evaluated through tools of statistical data analysis. The results show that proper elements allow one to reconnect the fragments to their parent body.

Design of a motion system for 3D printed snakebot

This article presents the results of work related to design, analysis and selection of the electric motors, servos and elements of motion system for 3D printed snakebot. Electric motors and servos had to meet a number of requirements like dimensions, torque, RPM. The drivetrain allowed to drive the snakebot and rotate system allowed to torsional movement between adjacent robot modules. CAD model and analysis allowed to select the proper elements of drivetrain and rotate system. We built test stands and after verification we built the prototype. Next step after building the robot was to carry out tests to verify the mobility of the snake robot. We checked, among others, movement of servos in different planes, snakebot speed, driving at angle (up and down).

“The Fantastic Flying Books of Mr. Morris Lessmore” de William Joyce e Brandon Oldenburg: quando o som se mostra dominante na construção de uma narrativa de texto e imagens.

Through the short film “The Fantastic Flying Books of Mr. Morris Lessmore” by William Joyce and Brandon Oldenburg, with music by John Hunter, we intend to realize how this component constructs the poetic and affective imaginary of the work. Facing us with a film without words, we perceive that all the imaginary is constructed in the discourse of images and sounds. We know that the sound component was designed in close collaboration with the filmmakers. In this sense, it comes from a proposal made by William Joyce and Brandon Oldenburg, in the sense that the musical component is based on the song “Pop Goes the Weasel”. The composer, with this information, outlines his work proposal which, in addition to citing the proposed source, calls the “Suite”. In our work, it is our intention to understand how the sound is constructed in order to elucidate these contents, but also the techniques of composition employed. We will look at how the composer integrates the song through the use of intertextuality, as well as how the proper elements of the Suite form are shown. Because Suite is a Baroque form, we will try to understand if its constituents demonstrate the elements present in the Affect Theory, popular theory at the time in the determination with expressive contents of a work. With this film, we realize that music, emphasizing the image, builds another level of meaning, another way of experiencing life and art.

Tax expenditures w podatkach lokalnych w Polsce jako instrument lokalnej polityki podatkowej

The subject of research was the size and diversity of use of tax expenditures by Polish municipalities with the goal to determine their relation to the local tax policy objectives. The authors used typical methods for social science, i.e., the methods of empirical cognition, observation in particular. In order to prove the influence of the municipal tax policy on the implementation of local tax policy objectives, the correlation analysis was used. The results show a considerable varied use of tax expenditures between Polish municipalities and a fairly significant relationship between the preferences used in local tax policy and the effects of its application assumed by local units. The results of this research can be used by decision-makers in the process of creating tax policy, especially in choosing proper elements of taxes, such as the categories of tax expenditures.

A pair of Jovian Trojans at the L4 Lagrange point

ABSTRACT Asteroid pairs, two objects that are not gravitationally bound to one another, but share a common origin, have been discovered in the Main belt and Hungaria populations. Such pairs are of major interest, as the study of their evolution under a variety of dynamical influences can indicate the time since the pair was created. To date, no asteroid pairs have been found in the Jovian Trojans, despite the presence of several binaries and collisional families in the population. The search for pairs in the Jovian Trojan population is of particular interest, given the importance of the Trojans as tracers of planetary migration during the Solar system’s youth. Here we report a discovery of the first pair, (258656) 2002 ES76 and 2013 CC41, in the Jovian Trojans. The two objects are approximately the same size and are located very close to the L4 Lagrange point. Using numerical integrations, we find that the pair is at least 360 Myr old, though its age could be as high as several Gyrs. The existence of the (258656) 2002 ES76–2013 CC41 pair implies there could be many such pairs scattered through the Trojan population. Our preferred formation mechanism for the newly discovered pair is through the dissociation of an ancient binary system, triggered by a sub-catastrophic impact, but we can not rule out rotation fission of a single object driven by YORP torques. A by-product of our work is an up-to-date catalogue of Jovian Trojan proper elements, which we have made available for further studies.

On the accuracy of position of the linear secular resonance g − g5 in the proper elements’ space

ABSTRACT An in-depth analysis is presented of the accuracy of position of the linear secular resonance g − g5 in the phase space of proper elements, as determined by the recently introduced polynomial fit method. Different attempts to pinpoint the exact location of this resonance are described, leading to improvement in the accuracy of resonance position achieved via local adjustments of the new method and measured in comparison with the corresponding positions of selected asteroids. The resonant state and proper frequencies of the longitude of perihelion of these asteroids are determined, and compared to the catalogue values computed in the course of determination of their synthetic proper elements. The problem of cycle slips, affecting the computation of frequencies, is thoroughly examined and successfully explained, and the procedure of double filtering of the time series of proper values to remove the cycle slips proposed. The results of tests of the new approach have shown that the accuracy of newly determined frequencies is significantly improved with respect to the previously available values.

Traumatic Brain Injury: A Forensic Approach: A Literature Review

: Traumatic brain injury (TBI) is the principal cause of invalidity and death in the population under 45 years of age worldwide. : This mini-review aims to systematize the forensic approach in neuropathological studies, highlighting the proper elements to be noted during external, radiological, autoptical, and histological examinations with particular attention paid to immunohistochemistry and molecular biology. : In the light of the results of this mini-review, an accurate forensic approach can be considered mandatory in the examination of suspected TBI with medico-legal importance, in order to gather all the possible evidence to corroborate the diagnosis of a lesion that may have caused, or contributed to, death. From this point of view, only the use of an evidence-based protocol can reach a suitable diagnosis, especially in those cases in which there are other neuropathological conditions (ischemia, neurodegeneration, neuro-inflammation, dementia) that may have played a role in death. : This is even more relevant when corpses, in an advanced state of decomposition, are studied, where the radiological, macroscopic and histological analyses fail to give meaningful answers. In these cases, immune-histochemical and molecular biology diagnostics are of fundamental importance and a forensic neuropathologist has to know them. Particularly, MiRNAs are promising biomarkers for TBI both for brain damage identification and for medico-legal aspects, even if further investigations are required to validate the first experimental studies. In the same way, the genetic substrate should be examined during any forensic examination, considering its importance in the outcome of TBI.

Hidden Aspects of the Research ADOS Are Bound to Affect Autism Science

The research-grade Autism Diagnostic Observational Schedule (ADOS) is a broadly used instrument that informs and steers much of the science of autism. Despite its broad use, little is known about the empirical variability inherently present in the scores of the ADOS scale or their appropriateness to define change and its rate, to repeatedly use this test to characterize neurodevelopmental trajectories. Here we examine the empirical distributions of research-grade ADOS scores from 1324 records in a cross-section of the population comprising participants with autism between five and 65 years of age. We find that these empirical distributions violate the theoretical requirements of normality and homogeneous variance, essential for independence between bias and sensitivity. Further, we assess a subset of 52 typical controls versus those with autism and find a lack of proper elements to characterize neurodevelopmental trajectories in a coping nervous system changing at nonuniform, nonlinear rates. Repeating the assessments over four visits in a subset of the participants with autism for whom verbal criteria retained the same appropriate ADOS modules over the time span of the four visits reveals that switching the clinician changes the cutoff scores and consequently influences the diagnosis, despite maintaining fidelity in the same test's modules, room conditions, and tasks' fluidity per visit. Given the changes in probability distribution shape and dispersion of these ADOS scores, the lack of appropriate metric spaces to define similarity measures to characterize change and the impact that these elements have on sensitivity-bias codependencies and on longitudinal tracking of autism, we invite a discussion on readjusting the use of this test for scientific purposes.

Spin clusters inside four young asteroid groups

ABSTRACT Asteroid groups may either form because of collisions or because of spin induced fission. Recently it has been shown that young spin clusters tend to form more frequently in young collisional families than in older groups. Here, we study the occurrence of spin clusters inside four very recently identified asteroid groups: the (525) Adelaide, (2258) Viipuri, (6142) Tantawi, and (18429) (1994 AO1) groups. Using combinations of techniques based on backward numerical simulations, we identify four spin pairs among the family members. All groups have fractions of observed spin clusters well above 5 per cent, so confirming an observed trend for other young asteroid groups. The (2258) Viipuri and (18429) (1994 AO1) groups are compatible with an origin as a spin clusters themselves, and could be other occurrences of cascade spin clusters, as recently detected in other asteroid groups. Finally, the separation between collisional asteroid families and spin clusters in domains of dispersion of proper semimajor axis, σa, versus age seems to be more complex than previously thought. While spin clusters tend to be much more compact in proper elements than collisional families, there appears to be a transition region in σa where both the groups be found.

Hidden Aspects of the Research-ADOS are Bound to Affect Autism Science

The research-grade ADOS is a broadly used instrument that informs and steers much of the science of Autism. Despite its broad use, little is known about the empirical variability inherently present in the scores of the ADOS scale, or their appropriateness to define change, to repeatedly use this test to characterize neurodevelopmental trajectories. Here we examine the empirical distributions of research-grade ADOS scores from 1,324 records in a cross-section of the population comprising participants with autism between 5-65 years of age. We find that these empirical distributions violate the theoretical requirements of normality and homogeneous variance, essential for independence between bias and sensitivity. Further, we assess a subset of 52 typical controls vs. those with autism and find lack of proper elements to characterize neurodevelopmental trajectories in a coping nervous system changing at non-uniform, non-linear rates. Lastly, longitudinally repeating the assessments over 4 visits in a subset of the participants with autism for whom verbal criteria kept the same appropriate ADOS modules over the timespan of the 4 visits, reveals that switching the clinician, changes the cutoff scores, and consequently, influences the diagnosis, despite maintaining fidelity in the same test’s modules, room conditions and tasks’ fluidity per visit. Given the changes in probability distribution shape and dispersion of these ADOS scores, the lack of appropriate metric spaces, and the impact that these elements have on sensitivity-bias co-dependencies, and on longitudinal tracking of autism, we invite a discussion on the use of this test for scientific purposes.