355 research outputs found

    Localised enamel hypoplasia of human deciduous canines: genotype or environment?

    Get PDF
    The document attached has been archived with permission from the Australian Dental Association (9th Jan 2008). An external link to the publisher’s copy is included.A discrete area of defective enamel formation that appears on the labial surface of the crowns of deciduous canine teeth has been described in both recent and prehistoric human population, with reported frequencies varying from 1 to 45 per cent. Suggestions about the aetiology of this localized hypoplasia range from genotypic factors to environmental conditions and systemic effects. The major aims of this study were to describe the frequency of occurrence and pattern of expression of the lesion in Australian Aboriginal and Caucasian ethnic groups, and to clarify the role of genetic factors by examining a sample of twins. The study sample consisted of dental casts of 181 pairs of Australian Caucasian twins, 215 Aborigines and 122 Caucasian singletons, together with 253 extracted deciduous canines. Examination of dental casts and extracted teeth was undertaken under 2X magnification with emphasis being placed upon location and expression of the lesion. The defect was observed in 49 per cent of twins and 44 per cent of Aborigines, but only 36 per cent of singletons. The percentages of affected teeth in each group were: 18 per cent in twins, 17 per cent in Aborigines and 13 per cent in Caucasians. A significant proportion of the defects occurred on the mesial aspect of the labial surface, in the middle area incisocervically, with the majority in the lower jaw. Anumber of significant differences in frequency were observed between groups, sexes, arches and sides. The results confirm some of the findings of previous studies, but also suggest that none of environmental, genetic or systemic factors can be ruled out as being involved in aetiology of the defect. The higher incidence of the lesion occurring on the mesial aspect of the labial surface is suggestive of physical trauma. Also, the vulnerability of the prominent developing mandibular canine, with its thin or missing labial covering of bone, would be expected to lead to higher prevalence of the lesion in the lower jaw. Although not definitive, the results of concordance analyses in twins were suggestive of a possible genetic predisposition in the formation of the lesion. Further research with a greater clinical orientation and emphasis on determing specific aetiological factors within any given environment in different ethnic groups may provide better insight into the ambiguous aetiology of the hypoplastic enamel defect.Sue Taji, Toby Hughes, Jim Rogers, Grant Townsen

    Optimizing Wildlife Monitoirng Strategies in a Dynamic Setting (Poster)

    Get PDF
    Long term, broadly distributed datasets are ideal for effective wildlife management.  However, collecting and utilizing these data present a variety of challenges to management agencies.  Idaho Department of Fish and Game is currently trying to optimize their use of monitoring resources for mule deer (Odocoileus hemionus) throughout Idaho.  Three areas are being investigated for their potential to accomplish this goal: cost effectiveness, data utilization, and efficiency in data collection.  An analysis of the cost effectiveness of monitoring methods is currently being conducted.  This analysis varies the amount of each type of data available to the population model used to estimate abundance.  The precision, credible interval width (CRI), associated with the estimate is used as the measure of effectiveness, mean 95% CRIs range from 9278 - 9804.  This measure of precision is then combined with the cost of the collection technique to compare the cost effectiveness of different monitoring methods.  Further research will focus on a weighting scheme that weights data types by both sampling precision and reliability.  Thereby allowing managers to fully utilize all available data sources based on relative quality within the framework of the population model.  A third line of research focuses on increasing the efficiency of monitoring effort through an alternative sampling design derived from seasonal nutrition.  The previous lines of research will then be combined to solve a dynamic programming problem to determine the optimal methods for monitoring population abundance while accounting for changes in the availability of monitoring resources over space and time

    TRY plant trait database - enhanced coverage and open access

    Get PDF
    Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

    Integrating isotopes and documentary evidence : dietary patterns in a late medieval and early modern mining community, Sweden

    Get PDF
    We would like to thank the Archaeological Research Laboratory, Stockholm University, Sweden and the Tandem Laboratory (Ångström Laboratory), Uppsala University, Sweden, for undertaking the analyses of stable nitrogen and carbon isotopes in both human and animal collagen samples. Also, thanks to Elin Ahlin Sundman for providing the δ13C and δ15N values for animal references from Västerås. This research (Bäckström’s PhD employment at Lund University, Sweden) was supported by the Berit Wallenberg Foundation (BWS 2010.0176) and Jakob and Johan Söderberg’s foundation. The ‘Sala project’ (excavations and analyses) has been funded by Riksens Clenodium, Jernkontoret, Birgit and Gad Rausing’s Foundation, SAU’s Research Foundation, the Royal Physiographic Society of Lund, Berit Wallenbergs Foundation, Åke Wibergs Foundation, Lars Hiertas Memory, Helge Ax:son Johnson’s Foundation and The Royal Swedish Academy of Sciences.Peer reviewedPublisher PD

    Habitat Quality Influences Migratory Strategy of Female White Tailed Deer

    Get PDF
    Partial migration is a life history strategy that is common for ungulate species living in seasonal environments.  One factor that influences the decision to migrate by ungulates is access to high quality habitat.  We evaluated the influence of access to winter habitat of high quality on the probability of an individual migrating, seasonal habitat use between and within migratory and resident classes of deer, and the effects of this decision on the survival of female white-tailed deer.  We radio-collared 67 female white-tailed deer (Odocoileu virginianus) in 2012 and 2013. The odds of being a migrant increased as home range size increased and decreased as proportion of cropland within home range in winter increased.  The habitat with the highest relative probability of use in winter for residents was pasture (1.00, SD = 0.01) and for migrants was riparian (0.73, SD = 0.39). In summer both groups had the highest relative probability of using pasture (resident = 0.96, SD = 0.15; migrant = 0.99, SD = 0.08).  We integrated the migration probability and survival models to estimate annual and seasonal survival rates of migrants and residents. We found no difference between the annual and seasonal rates of survival for the different migration strategies.  Our results indicate that access to habitat of high quality may be a strong influence on a female white-tailed deer’s decision to migrate.  We suggest the presence of partial migration in a population may be a response to competition for high quality habitat

    An enigmatic hypoplastic defect of the maxillary lateral incisor in recent and fossil orangutans from Sumatra (Pongo abelii) and Borneo (Pongo pygmaeus)

    Get PDF
    Developmental dental pathologies provide insight into health of primates during ontogeny, and are particularly useful for elucidating the environment in which extant and extinct primates matured. Our aim is to evaluate whether the prevalence of an unusual dental defect on the mesiolabial enamel of the upper lateral incisor, thought to reflect dental crowding during maturation, is lesser in female orangutans, with their smaller teeth, than in males; and in Sumatran orangutans, from more optimal developmental habitats, than in those from Borneo. Our sample includes 49 Pongo pygmaeus (87 teeth), 21 P. abelii (38 teeth), Late Pleistocene paleo-orangutans from Sumatra and Vietnam (67 teeth), Late Miocene catarrhines Lufengpithecus lufengensis (2 teeth), and Anapithecus hernyaki (7 teeth). Methods include micro-CT scans, radiography, and dental metrics of anterior teeth. We observed fenestration between incisor crypts and marked crowding of unerupted crowns, which could allow tooth-to-tooth contact. Tooth size does not differ significantly in animals with or without the defect, implicating undergrowth of the jaw as the proximate cause of dental crowding and defect presence. Male orangutans from both islands show more defects than do females. The defect is significantly more common in Bornean orangutans (71 %) compared to Sumatran (29 %). Prevalence among fossil forms falls between these extremes, except that all five individual Anapithecus show one or both incisors with the defect. We conclude that maxillary lateral incisor defect is a common developmental pathology of apes that is minimized in optimal habitats and that such evidence can be used to infer habitat quality in extant and fossil apes

    Construction of a Global Pain Systems Network Highlights Phospholipid Signaling as a Regulator of Heat Nociception

    Get PDF
    The ability to perceive noxious stimuli is critical for an animal's survival in the face of environmental danger, and thus pain perception is likely to be under stringent evolutionary pressure. Using a neuronal-specific RNAi knock-down strategy in adult Drosophila, we recently completed a genome-wide functional annotation of heat nociception that allowed us to identify α2δ3 as a novel pain gene. Here we report construction of an evolutionary-conserved, system-level, global molecular pain network map. Our systems map is markedly enriched for multiple genes associated with human pain and predicts a plethora of novel candidate pain pathways. One central node of this pain network is phospholipid signaling, which has been implicated before in pain processing. To further investigate the role of phospholipid signaling in mammalian heat pain perception, we analysed the phenotype of PIP5Kα and PI3Kγ mutant mice. Intriguingly, both of these mice exhibit pronounced hypersensitivity to noxious heat and capsaicin-induced pain, which directly mapped through PI3Kγ kinase-dead knock-in mice to PI3Kγ lipid kinase activity. Using single primary sensory neuron recording, PI3Kγ function was mechanistically linked to a negative regulation of TRPV1 channel transduction. Our data provide a systems map for heat nociception and reinforces the extraordinary conservation of molecular mechanisms of nociception across different species. © 2012 Neely et al

    Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set

    Get PDF
    We report a measurement of the bottom-strange meson mixing phase \beta_s using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays in which the quark-flavor content of the bottom-strange meson is identified at production. This measurement uses the full data set of proton-antiproton collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity. We report confidence regions in the two-dimensional space of \beta_s and the B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2, -1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in agreement with the standard model expectation. Assuming the standard model value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +- 0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +- 0.009 (syst) ps, which are consistent and competitive with determinations by other experiments.Comment: 8 pages, 2 figures, Phys. Rev. Lett 109, 171802 (2012
    corecore