Copyright © 2015, SEPM (Society for Sedimentary Geology). Accurate paleoenvironmental reconstruction relies on the correct interpretation of the postmortem history of skeletal remains in shelly assemblages. In contrast to marine settings, actualistic taphonomic studies are lacking for shell-rich concentrations in freshwater riverine systems. In particular, the taphonomic pathways and the origins of taphonomic signatures that are recorded in bioclasts from fluvial settings are poorly known. In this study, we addressed this issue by comparing the taphonomic signatures and shell-damage profiles among shells of freshwater mollusks recorded both in death and in fossil assemblages from the same fluvial environment. Our data indicated that dissolution was the most pervasive taphonomic process leading to the destruction of the shells. The loss of taphonomic information extended beyond shell dissolution in the riverbed, or the early diagenesis in the sedimentary record. The loss of biological information from the living community through the death assemblage, until the incorporation of shells as fossils, mainly occurred during the time the shells were in the sediment-water interface. Though this destruction affected primarily dead shells, reworked fossils also became vulnerable because they were carried out into the river load again by channel avulsion. A model that included the main taphonomic pathways followed by the molluscan shells in the fluvial Touro Passo Formation (Pleistocene-Holocene) is discussed. In this model, two main destructive domains were recognized, which were the biological, physical, and chemical processes operating at the taphonomically active zone (=TAZ domain) and the pedogenetic domain.

We investigate the dispersion relation for low frequency electromagnetic waves propagating parallel to the ambient magnetic field, considering that the velocity distributions of ions and electrons can be either bi-Maxwellian of product bi-kappa distributions. The effect of the anisotropy and non-thermal features associated to the product-bi-kappa distributions on the firehose instability are numerically investigated. The general conclusion to be drawn from the results obtained is that the increase in non-thermal features which is consequence of the decrease of the κ indexes in the ion distribution contributes to increase the instability in magnitude and wave number range, in comparison with bi-Maxwellian distributions with similar temperature anisotropy, and that the increase of non-thermal features in the electron distribution contributes to the quenching of the instability, which is nevertheless driven by the anisotropy in the ion distribution. Significant differences between results obtained either considering product-bi-kappa distributions or bi-kappa distributions are also reported.

OBJECTIVE: To evaluate the association between sociodemographic factors and self-reported use of mouthwashes in a city in the south of Brazil over a time span of 13 years. METHODS: The study involves a comparison of two household surveys conducted in 1996 and 2009. Respectively, 850 and 982 households were included in each year. The mother of the family answered to a structured questionnaire to provide sociodemographic data. Self-reported use of mouthwash was evaluated in a binary manner (yes/no). Multivariate Poisson regression models were used to estimate proportion ratios (PR) and 95% confidence intervals (95% CI). RESULTS: The proportion of mouthwash use increased significantly from 10.8% to 24.2% after 13 years. The probability of using mouthwashes increased more than two times from 1996 to 2009 (PR = 2.25 95% CI 1.80-2.82). Higher probabilities for using mouthwashes were observed in households with higher income (PR = 2.63 95% CI 1.97-3.51) and in those households where the mothers had higher educational levels (PR = 1.46 95% CI 1.05-2.03). CONCLUSION: Higher family income and higher maternal educational level were associated with self-reported use of mouthwashes in a higher proportion of households.

AIM: To assess sociodemographic and behavioural risk factors for periodontal attachment loss (PAL) progression after 5 years in an urban sample from south Brazil. METHODS: At baseline, 1586 subjects, 14 years and older, were derived using a multistage probabilistic sample strategy. At follow-up, 653 of 755 subjects had >/=6 teeth and were included in this analysis. A modified multiple Poisson regression was used to calculate adjusted relative risks (RR) and 95% confidence intervals (CI). RESULTS: Overall, 247 (37.8%) subjects exhibited PAL progression >/=3 mm in >/=4 teeth. Subjects older than 30 years had approximately two times higher risk of having PAL progression than younger subjects. Subjects with low education had 53% higher risk (RR = 1.53; 95% CI:1.06-2.22) of PAL progression compared to those with high education. A significant interaction between gender and smoking was observed. Among never-smokers, males were 33% more likely (RR = 1.33; 95% CI:1.06-1.66) to experience PAL progression than females. Among smokers, there was 8% increased risk of PAL progression (RR = 1.08; 95% CI:1.01-1.14) for males and 21% (RR = 1.21; 95% CI:1.11-1.33) for females per 10 packyears. Skin colour, socioeconomy, dental care and diabetes were not significantly associated with PAL progression after statistical adjustment. CONCLUSION: Sociodemographic factors and smoking are independent risk factors for PAL progression in this Brazilian population.

This work describes a new approach to gesture mapping in a performance with a traditional musical instrument and live electronics based upon theories of embodied music cognition (EMC) and musical gestures. Considerations on EMC and how gestures affect the experience of music inform different mapping strategies. Our intent is to enhance the expressiveness and the liveness of performance by tracking gestures via a multimodal motion capture system and to use motion data to control several features of the music. After a review of recent research in the field, a proposed application of such theories to a performance with electric guitar and live electronics will follow, focusing both on aspects of meaning formation and motion capturing.

Epidemiologic studies of aggressive periodontitis have used different study designs and a range of examination methods and case definitions, and this greatly complicates the study of disease prevalence in populations. The wide range of disease case definitions, in particular, profoundly impacts the reported rate of disease, and the use of a standard disease definition is strongly recommended. Surveys of aggressive periodontitis that use only clinical examinations, without radiographic examination to confirm the presence of a distinctive pattern of tissue loss, may overestimate the prevalence of this disease, particularly when a low threshold of attachment loss is used. The prevalence of aggressive periodontitis varies significantly between populations, and differences in race/ethnicities seem to be a key factor. Studies consistently show that aggressive periodontitis is most prevalent in Africa and in populations of African descent and is least prevalent in Caucasians in Europe and North America. Among children and young adults the prevalence of this disease is higher in older than in younger age groups. Most studies show comparable disease prevalence in male and female subjects. These findings show that aggressive periodontitis is a significant health problem in certain populations. This review also highlights a lack of information on the epidemiology and demographics of this disease in many parts of the world, particularly in Asia and Africa. Epidemiologic studies of aggressive periodontitis in high-risk populations are important and could provide vital data on the determinants of this disease, and this information is needed for the establishment of effective health-promotion measures.

Known radiation emission mechanisms in plasmas include bremmstrahlung (or free-free emission), gyro- and synchrotron radiation, cyclotron maser, and plasma emission. For unmagnetized plasmas, only bremmstrahlung and plasma emissions are viable. Of these, bremmstrahlung becomes inoperative in the absence of collisions, and the plasma emission requires the presence of electron beam, followed by various scattering and conversion processes. The present Letter proposes a new type of radiation emission process for plasmas in a state of thermodynamic quasi-equilibrium between particles and enhanced Langmuir turbulence. The radiation emission mechanism proposed in the present Letter is not predicted by the linear theory of thermal plasmas, but it relies on nonlinear wave-particle resonance processes. The electromagnetic particle-in-cell numerical simulation supports the new mechanism.

A recent paper [Ziebell et al., Phys. Plasmas 21, 010701 (2014)] discusses a new type of radiation emission process for plasmas in a state of quasi-equilibrium between the particles and enhanced Langmuir turbulence. Such a system may be an example of the so-called “turbulent quasi-equilibrium.” In the present paper, it is shown on the basis of electromagnetic weak turbulence theory that an initial thermal equilibrium state (i.e., only electrostatic fluctuations and Maxwellian particle distributions) transitions toward the turbulent quasi-equilibrium state with enhanced electromagnetic radiation spectrum, thus demonstrating that the turbulent quasi-equilibrium discussed in the above paper correctly describes the weakly turbulent plasma dynamically interacting with electromagnetic fluctuations, while maintaining a dynamical steady-state in the average sense.

Background: Dentin hypersensitivity (DH) is a clinical condition with potential implications for patients. However, little is known about its occurrence and determinants in the general population. The aim of this study was to assess the prevalence and risk indicators of DH in Porto Alegre, Brazil. Methods: A representative multistage probability sample of 1,023 adults aged >/=35 years was obtained. Individuals were interviewed and were clinically examined in their homes. DH was assessed dichotomously in all present teeth by a blast of air and a manual probe. Teeth restored with crowns and presenting with carious cavitation were excluded. Survey logistic regression using sampling weights was applied to assess demographics, behavioral and clinical determinants. Results: Overall prevalence estimates for DH diagnosed by air and probe were 33.4% and 34.2%. DH affected 1.0 tooth per individual, and approximately 10% of teeth with gingival recession (GR) had DH. In a multivariate model for DH diagnosed with air, females had increased chance of DH [odds ratio (OR): 2.14; 95% confidence interval (CI): 1.57-2.91]. Smoking, periodontal treatment, and GR were also associated with increased DH chances. The chance of DH was lower (OR: 0.47, 95% CI: 0.29-0.76) among individuals >/=60 than 35 to 49 years old. Oral hygiene practices, socioeconomic and educational statuses, dental visits, and gingival inflammation were not associated with DH. Conclusion: DH may be considered a concern in a Brazilian general population. Reduction of DH may be achieved by smoking cessation and periodontal health improvements.