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The Academy of Dental Materials: Providing roots and wings.
ObjectivesThe long history of the Academy of Dental Materials (ADM) is documented with its strategies (a) to rapidly communicate science among its members, (b) to establish special awards to stimulate new science, and (c) to develop new dental materials scientists.MethodsWe searched the history of the last 35 years of the ADM newsletters, transactions, journals, and officer notes. We document the (a) presidents, (b) meeting history, (c) membership growth, and (d) development of special awards through 2019 with the recent creation of the ADM Marshall Post-Doctoral Award.ResultsThere are 36 years of recent ADM history, 42 international meetings, membership growth to 400 individuals from 15 countries, service of 19 presidents, Paffenbarger annual Awardees since 1989, induction of >200 fellows, and recognition of the first winner of Marshall Post-Doctoral Award in 2018. New directions for recruiting members are suggested. Three potential new thrusts for the organization are presented: artificial intelligence, genetic engineering, and intensive member mentoring.SignificanceThese suggestions for the ADM provide a path for the ADM to continue to adapt to the ever changing scientific landscape
The Galactic bulge as seen in optical surveys
The bulge is a region of the Galaxy of tremendous interest for understanding
galaxy formation. However measuring photometry and kinematics in it raises
several inherent issues, such as severe crowding and high extinction in the
visible. Using the Besancon Galaxy model and a 3D extinction map, we estimate
the stellar density as a function of longitude, latitude and apparent magnitude
and we deduce the possibility of reaching and measuring bulge stars with Gaia.
We also present an ongoing analysis of the bulge using the Canada-France-Hawaii
Telescope.Comment: In SF2A-2008: Proceedings of the Annual meeting of the French Society
of Astronomy and Astrophysic
Effects of Enamel Paint on the Behavior and Survival of the Periodical Cicada, \u3ci\u3eMagicicada Septendecim\u3c/i\u3e (Homoptera) and the Lesser Migratory Grasshopper, \u3ci\u3eMelanoplus Sanguinipes (Orthoptera).
We present information compiled from several studies on the effects of methods for marking individual arthropods on their longevity and behavior. Results from our own research on effects of enamel paint marking on two in- sect species, the periodical cicada, Magicicada septendecim, and the lesser migratory grasshopper, Melanoplus sanguinipes, are also presented. Neither species showed any adverse survivorship or behavioral effects from marking
A Dynamical Analysis of the Proposed Circumbinary HW Virginis Planetary System
In 2009, the discovery of two planets orbiting the evolved binary star system
HW Virginis was announced, based on systematic variations in the timing of
eclipses between the two stars. The planets invoked in that work were
significantly more massive than Jupiter, and moved on orbits that were mutually
crossing - an architecture which suggests that mutual encounters and strong
gravitational interactions are almost guaranteed. In this work, we perform a
highly detailed analysis of the proposed HW Vir planetary system. First, we
consider the dynamical stability of the system as proposed in the discovery
work. Through a mapping process involving 91,125 individual simulations, we
find that the system is so unstable that the planets proposed simply cannot
exist, due to mean lifetimes of less than a thousand years across the whole
parameter space. We then present a detailed re-analysis of the observational
data on HW Vir, deriving a new orbital solution that provides a very good fit
to the observational data. Our new analysis yields a system with planets more
widely spaced, and of lower mass, than that proposed in the discovery work, and
yields a significantly greater (and more realistic) estimate of the uncertainty
in the orbit of the outermost body. Despite this, a detailed dynamical analysis
of this new solution similarly reveals that it also requires the planets to
move on orbits that are simply not dynamically feasible. Our results imply that
some mechanism other than the influence of planetary companions must be the
principal cause of the observed eclipse timing variations for HW Vir. If the
sys- tem does host exoplanets, they must move on orbits differing greatly from
those previously proposed. Our results illustrate the critical importance of
performing dynamical analyses as a part of the discovery process for
multiple-planet exoplanetary systems.Comment: Accepted for publication in Monthly Notices of the Royal Astronomical
Societ
Reactive attachment disorder in the general population: a hidden ESSENCE disorder
Reactive attachment disorder (RAD) is a severe disorder of social functioning. Previous research has shown that children with RAD may have poor cognitive and language abilities; however, findings mainly come from biased, institutionalised samples. This paper describes the characteristics of all children who were given a suspected or likely diagnosis of reactive attachment disorder in an epidemiological study of approximately 1,600 children investigating the prevalence of RAD in the general population. We found that children with RAD are more likely to have multiple comorbidities with other disorders, lower IQs than population norms, more disorganised attachment, more problem behaviours, and poorer social skills than would be found in the general population and therefore have a complex presentation than can be described as ESSENCE. We discuss the clinical and educational implications
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