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Objectives:During orthodontic arch expansion, the teeth are displaced against the perioral soft tissues. This can affect the equilibrium of forces that are thought to act on teeth, with consequent implications for long-term stability. The aim of this study was to investigate the effect of incremental lower lip advancement on intraoral pressure and electromyographic (EMG) activity of the lower lip.Materials and methods:Intraoral pressure and EMG activity was measured in 10 participants (2 males, 8 females; 22 years ± 7 months) as the lower lip was incrementally advanced using three custom-made vacuum-formed stents of differing labial thicknesses (0.5, 2.5, and 4.5 mm). A task paradigm including at rest recordings and maximal voluntary contraction was completed for each tray.Results:Resting lip pressure generated increased as the lower lip was advanced (P < 0.001). The EMG activity of the lower lip increased significantly (P < 0.001) only once the lip was advanced from 2.5 to 4.5 mm. For the pressure recordings, the response to incremental lip advancement showed considerable individual variation.Conclusions:These findings suggest that the initial pressure increase on the lower incisors was mostly likely due to the inherent viscoelastic properties of the lower lip, while the pressure increase between the 2.5 and 4.5 mm advancement was due to increased muscle activity. Each individual also responded to lower lip advancement in a different yet subject-specific manner.

A weekly cycle in aerosol pollution and some meteorological quantities is observed over Europe. In the present study we exploit this effect to analyse aerosol-cloud-radiation interactions. A weekly cycle is imposed on anthropogenic emissions in two general circulation models that include parameterizations of aerosol processes and cloud microphysics. It is found that the simulated weekly cycles in sulfur dioxide, sulfate, and aerosol optical depth in both models agree reasonably well with those observed indicating model skill in simulating the aerosol cycle. A distinct weekly cycle in cloud droplet number concentration is demonstrated in both observations and models. For other variables, such as cloud liquid water path, cloud cover, top-of-the-atmosphere radiation fluxes, precipitation, and surface temperature, large variability and contradictory results between observations, model simulations, and model control simulations without a weekly cycle in emissions prevent us from reaching any firm conclusions about the potential aerosol impact on meteorology or the realism of the modelled second aerosol indirect effects., Atmospheric Chemistry and Physics, 9 (21), ISSN:1680-7375, ISSN:1680-7367

In disasters, one of the major challenges is the identification of the dead. This is complicated in cases where young victims and, sometimes, young survivors are involved. Often, there are no dental treatment records that can be usefully employed and, hence, identification has to be relied heavily on ageing. Developing teeth are generally considered to be the most reliable indicators of maturation and, by extension, of chronological age at death. This is because teeth are more durable, their degree of development can be observed directly from the living or deceased individual, and tooth formation is relatively unaffected by disease, malnutrition, or endocrine disorders. Unfortunately, the calculation of dental maturation and its conversion to a useful indicator of chronological age is a time-consuming process, which can be frustrating in the face of an overwhelming demand after a disaster such as the Thai Tsunami or Hurricane Katrina. The authors report on the development of a novel, automated “point and click” graphical user interface that can be used to calculate the age of a known individual from a simple dental radiograph. The authors apply the method to three ethnic populations living in New Zealand: children of European, Maori, and Pacific Island descent.

Ionization of the atmosphere due to precipitating solar energetic particles as well as magnetospheric particles is a major source of thermospheric electron density. In this paper we evaluate numerical simulations of the 3-D spatial and temporal electron densities produced by these particle populations through a comparison with incoherent scatter radar observations. The 3-D precipitation patterns are determined with the Atmospheric Ionization Module Osnabruck (AIMOS). We use a version of the general circulation and chemistry model Hamburg Model of the Neutral and Ionized Atmosphere (HAMMONIA) enhanced by ion chemistry to calculate the impact of particle ionization on the electron density. These modeled data are compared to radar observations from European Incoherent Scatter Svalbard and Tromso as well as the incoherent scatter radar stations at Millstone Hill and Sondrestrom. Particle precipitation is severely affected by geomagnetic disturbance and latitude. Therefore, different locations (inside the polar cap and at auroral latitudes) and geomagnetic conditions are included in the comparison. The main results of the paper can be summarized as follows: (1) as expected, particle forcing will significantly improve modeled electron density in comparison to results of the radar measurements; (2) in particular nighttime comparisons of the electron density are affected; here the particle forcing will account for a boost of 2 to 3 orders of magnitude.

A sample of pre-European Polynesian and Melanesian mandibles, modern Asian Indians and cadaveric European mandibles were investigated to establish the prevalence of a subcondylar tubercle and to attempt to relate its presence to mandibular function. Among the three population samples, the subcondylar tubercle appeared 1.5 times more frequently among the Polynesians/Melanesians, than either the Indian or European groups. It was fairly equally present on both sides in all three groups. Where it was present unilaterally, it was far more likely to be present on the left side. This left-side presence coincided with a significantly greater right-side condylar height and ramal width.