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Sample records for rapid population expansion

  1. Rapid adaptive evolution in novel environments acts as an architect of population range expansion.

    Science.gov (United States)

    Szűcs, M; Vahsen, M L; Melbourne, B A; Hoover, C; Weiss-Lehman, C; Hufbauer, R A

    2017-12-19

    Colonization and expansion into novel landscapes determine the distribution and abundance of species in our rapidly changing ecosystems worldwide. Colonization events are crucibles for rapid evolution, but it is not known whether evolutionary changes arise mainly after successful colonization has occurred, or if evolution plays an immediate role, governing the growth and expansion speed of colonizing populations. There is evidence that spatial evolutionary processes can speed range expansion within a few generations because dispersal tendencies may evolve upwards at range edges. Additionally, rapid adaptation to a novel environment can increase population growth rates, which also promotes spread. However, the role of adaptive evolution and the relative contributions of spatial evolution and adaptation to expansion are unclear. Using a model system, red flour beetles (Tribolium castaneum), we either allowed or constrained evolution of populations colonizing a novel environment and measured population growth and spread. At the end of the experiment we assessed the fitness and dispersal tendency of individuals originating either from the core or edge of evolving populations or from nonevolving populations in a common garden. Within six generations, evolving populations grew three times larger and spread 46% faster than populations in which evolution was constrained. Increased size and expansion speed were strongly driven by adaptation, whereas spatial evolutionary processes acting on edge subpopulations contributed less. This experimental evidence demonstrates that rapid evolution drives both population growth and expansion speed and is thus crucial to consider for managing biological invasions and successfully introducing or reintroducing species for management and conservation.

  2. Rapid global expansion of the fungal disease chytridiomycosis into declining and healthy amphibian populations.

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    Timothy Y James

    2009-05-01

    Full Text Available The fungal disease chytridiomycosis, caused by Batrachochytrium dendrobatidis, is enigmatic because it occurs globally in both declining and apparently healthy (non-declining amphibian populations. This distribution has fueled debate concerning whether, in sites where it has recently been found, the pathogen was introduced or is endemic. In this study, we addressed the molecular population genetics of a global collection of fungal strains from both declining and healthy amphibian populations using DNA sequence variation from 17 nuclear loci and a large fragment from the mitochondrial genome. We found a low rate of DNA polymorphism, with only two sequence alleles detected at each locus, but a high diversity of diploid genotypes. Half of the loci displayed an excess of heterozygous genotypes, consistent with a primarily clonal mode of reproduction. Despite the absence of obvious sex, genotypic diversity was high (44 unique genotypes out of 59 strains. We provide evidence that the observed genotypic variation can be generated by loss of heterozygosity through mitotic recombination. One strain isolated from a bullfrog possessed as much allelic diversity as the entire global sample, suggesting the current epidemic can be traced back to the outbreak of a single clonal lineage. These data are consistent with the current chytridiomycosis epidemic resulting from a novel pathogen undergoing a rapid and recent range expansion. The widespread occurrence of the same lineage in both healthy and declining populations suggests that the outcome of the disease is contingent on environmental factors and host resistance.

  3. Rise and fall of a wolf population: genetic diversity and structure during recovery, rapid expansion and drastic decline.

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    Jansson, E; Ruokonen, M; Kojola, I; Aspi, J

    2012-11-01

    The grey wolves (Canis lupus) of Finland have had a varied history, with a period of rapid population expansion after the mid-1990s followed by a decline with a current census size of about 140 wolves. Here, we investigate the impact of unstable population size and connectivity on genetic diversity and structure in a long-term genetic study of 298 Finnish wolves born in 1995-2009 and genotyped for 17 microsatellite loci. During the initial recovery and prior to population expansion, genetic diversity was high (1995-1997: LD-N(e)  = 67.2; H(o)  = 0.749; H(e)  = 0.709) despite a small census size and low number of breeders (N(c)  < 100; N(b)  < 10) likely reflecting the status of the Russian source population. Surprisingly, observed heterozygosity decreased significantly during the study period (t = -2.643, P = 0.021) despite population expansion, likely a result of an increase in inbreeding (F(IS)  = 0.108 in 2007-2009) owing to a low degree of connectivity with adjacent Russian wolf population (m = 0.016-0.090; F(ST)  = 0.086, P < 0.001) and population crash after 2006. However, population growth had a temporary positive impact on N(e) and number of family lines. This study shows that even strong population growth alone might not be adequate to retain genetic diversity, especially when accompanied with low amount of subsequent gene flow and population decline. © 2012 Blackwell Publishing Ltd.

  4. Rapid expansion of intravitreal drug injection procedures, 2000 to 2008: a population-based analysis.

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    Campbell, Robert J; Bronskill, Susan E; Bell, Chaim M; Paterson, J Michael; Whitehead, Marlo; Gill, Sudeep S

    2010-03-01

    To evaluate patterns of care for age-related macular degeneration following the introduction of vascular endothelial growth factor inhibitors. Using a population-based retrospective design, we studied monthly fee claims for intravitreal injections submitted to the Ontario Health Insurance Plan between January 1, 2000, and March 30, 2008, and linked procedures to the physicians who performed them. This database records physician services provided as part of universal health care insurance coverage in Ontario, Canada. This program covers all residents of Ontario, which had an average population of 12.1 million during the study period. Following regulatory approval of bevacizumab for colorectal cancer in 2005, off-label use of this drug for the treatment of retinal disease, particularly age-related macular degeneration, became increasingly common. The rate of intravitreal injections in Ontario rapidly grew 8-fold, and this growth preceded the availability of ranibizumab by more than a year. Moreover, in 2007, more than 50% of intravitreal injections in Ontario were performed by 3% of ophthalmologists. The development of vascular endothelial growth factor inhibitors has revolutionized the treatment of age-related macular degeneration. To our knowledge, this study is the first to quantify the dramatic uptake of these treatments at a population level. Our findings also suggest that off-label injection of bevacizumab was highly prevalent in Ontario. Serial intravitreal injections requiring direct physician administration and the concentration of injection procedures in the hands of a small number of ophthalmologists have the potential to affect services for other vision-threatening conditions.

  5. Homogenous Population Genetic Structure of the Non-Native Raccoon Dog (Nyctereutes procyonoides) in Europe as a Result of Rapid Population Expansion.

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    Drygala, Frank; Korablev, Nikolay; Ansorge, Hermann; Fickel, Joerns; Isomursu, Marja; Elmeros, Morten; Kowalczyk, Rafał; Baltrunaite, Laima; Balciauskas, Linas; Saarma, Urmas; Schulze, Christoph; Borkenhagen, Peter; Frantz, Alain C

    2016-01-01

    The extent of gene flow during the range expansion of non-native species influences the amount of genetic diversity retained in expanding populations. Here, we analyse the population genetic structure of the raccoon dog (Nyctereutes procyonoides) in north-eastern and central Europe. This invasive species is of management concern because it is highly susceptible to fox rabies and an important secondary host of the virus. We hypothesized that the large number of introduced animals and the species' dispersal capabilities led to high population connectivity and maintenance of genetic diversity throughout the invaded range. We genotyped 332 tissue samples from seven European countries using 16 microsatellite loci. Different algorithms identified three genetic clusters corresponding to Finland, Denmark and a large 'central' population that reached from introduction areas in western Russia to northern Germany. Cluster assignments provided evidence of long-distance dispersal. The results of an Approximate Bayesian Computation analysis supported a scenario of equal effective population sizes among different pre-defined populations in the large central cluster. Our results are in line with strong gene flow and secondary admixture between neighbouring demes leading to reduced genetic structuring, probably a result of its fairly rapid population expansion after introduction. The results presented here are remarkable in the sense that we identified a homogenous genetic cluster inhabiting an area stretching over more than 1500km. They are also relevant for disease management, as in the event of a significant rabies outbreak, there is a great risk of a rapid virus spread among raccoon dog populations.

  6. Homogenous Population Genetic Structure of the Non-Native Raccoon Dog (Nyctereutes procyonoides in Europe as a Result of Rapid Population Expansion.

    Directory of Open Access Journals (Sweden)

    Frank Drygala

    Full Text Available The extent of gene flow during the range expansion of non-native species influences the amount of genetic diversity retained in expanding populations. Here, we analyse the population genetic structure of the raccoon dog (Nyctereutes procyonoides in north-eastern and central Europe. This invasive species is of management concern because it is highly susceptible to fox rabies and an important secondary host of the virus. We hypothesized that the large number of introduced animals and the species' dispersal capabilities led to high population connectivity and maintenance of genetic diversity throughout the invaded range. We genotyped 332 tissue samples from seven European countries using 16 microsatellite loci. Different algorithms identified three genetic clusters corresponding to Finland, Denmark and a large 'central' population that reached from introduction areas in western Russia to northern Germany. Cluster assignments provided evidence of long-distance dispersal. The results of an Approximate Bayesian Computation analysis supported a scenario of equal effective population sizes among different pre-defined populations in the large central cluster. Our results are in line with strong gene flow and secondary admixture between neighbouring demes leading to reduced genetic structuring, probably a result of its fairly rapid population expansion after introduction. The results presented here are remarkable in the sense that we identified a homogenous genetic cluster inhabiting an area stretching over more than 1500km. They are also relevant for disease management, as in the event of a significant rabies outbreak, there is a great risk of a rapid virus spread among raccoon dog populations.

  7. Rapid palatal expansion: the role of microcirculation.

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    Bilello, G; Currò, G; Messina, P; Scardina, G

    2015-08-01

    Transverse palate modifications fall under expansive orthopedic therapy of the upper maxilla. The only practical approach to the problem on the transverse plane is that of performing the expansion of the maxillary arch through an opening of the median palatal suture. It is important to understand the changes of the vascular network in midpalatal suture following the starting of rapid maxillary expansion. It is critical to maintain the blood supply and circulation for the osteogenesis and bone remodeling after the expansion. The aim of this research was to evaluate the effects of rapid orthopedic expansion (REP) at the microcirculatory level through capillaroscopic examination. Fifteen patients in their developing years between 9 and 15 years of age (average age 12.16 years) were examined. The application of the REP was the first step in the planning of orthopedic-orthodontic treatment which foresaw further stages in the odonto-osseous movement. The method of Biomicroscopic Video-Imaging of the microcirculation of oral mucosa is performed through the technique of computerized capillaroscopy and the related software. From the results it is evident that immediately after achieving the expansion of the upper maxilla (t1), a slight decrease in the number of vessels per mm² can be observed. In addition, a slight ectasia can be observed in these vessels in comparison to t0. Comparing the videocapillaroscopic images of t1 and t2, an increase in the capillaries per mm² can be observed. Ectasia of the capillaries, though subject to strictly individual variables, can be considered perfectly normal and it is compatible with the normal biology and physiology of vessel microcirculation.

  8. Effect of rapid maxillary expansion on sleep characteristics in children

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    Navya Ashok; N. K. Sapna Varma; Ajith, V. V.; Siby Gopinath

    2014-01-01

    Introduction: Rapid maxillary expansion (RME) is an orthopedic treatment procedure routinely used to treat constricted maxillary arches and also a potential additional treatment in children presenting with sleep-disordered breathing (SDB). Aims and Objectives: The main objective of this study was to evaluate the effects of RME on sleep characteristics in children. Materials and Methods: Polysomnography was done on children of 8-13 years of age before expansion (T0), after expansion (T1) and a...

  9. Effect of rapid maxillary expansion on sleep characteristics in children

    National Research Council Canada - National Science Library

    Ashok, Navya; Varma, N K Sapna; Ajith, V V; Gopinath, Siby

    2014-01-01

    Rapid maxillary expansion (RME) is an orthopedic treatment procedure routinely used to treat constricted maxillary arches and also a potential additional treatment in children presenting with sleep-disordered breathing (SDB...

  10. Effect of rapid maxillary expansion on sleep characteristics in children

    National Research Council Canada - National Science Library

    Navya Ashok; N. K. Sapna Varma; V V Ajith; Siby Gopinath

    2014-01-01

    Introduction: Rapid maxillary expansion (RME) is an orthopedic treatment procedure routinely used to treat constricted maxillary arches and also a potential additional treatment in children presenting with sleep-disordered breathing (SDB...

  11. Effect of rapid maxillary expansion on sleep characteristics in children

    Directory of Open Access Journals (Sweden)

    Navya Ashok

    2014-01-01

    Full Text Available Introduction: Rapid maxillary expansion (RME is an orthopedic treatment procedure routinely used to treat constricted maxillary arches and also a potential additional treatment in children presenting with sleep-disordered breathing (SDB. Aims and Objectives: The main objective of this study was to evaluate the effects of RME on sleep characteristics in children. Materials and Methods: Polysomnography was done on children of 8-13 years of age before expansion (T0, after expansion (T1 and after a period of 3 months after retention (T2. Bonded rapid maxillary expander was cemented in all children. Inter-molar distance was also measured at T0 and T2. Statistical Analysis: Nonparametric Friedman test was used for comparing the averages of sleep parameters at different time period (T0, T1, T2. Wilcoxon signed ranks test was used for comparing the averages of inter-molar width (T0-T2. P < 0.05 were considered as significant. Results: All children showed an improvement in sleep parameters with an increase in sleep efficiency, decreased in arousal and desaturation index after expansion. Total sleep time showed a statistically significant increase after expansion. A statistically significant increase in inter-molar distance was obtained after expansion. Conclusions: Rapid maxillary expansion is a useful treatment option for improving quality of sleep even in normal children without SDB. It also induces widening of the maxilla, corrects posterior crossbites and improves maxillary and mandibular dental arch coordination.

  12. Effect of rapid maxillary expansion on sleep characteristics in children.

    Science.gov (United States)

    Ashok, Navya; Varma, N K Sapna; Ajith, V V; Gopinath, Siby

    2014-10-01

    Rapid maxillary expansion (RME) is an orthopedic treatment procedure routinely used to treat constricted maxillary arches and also a potential additional treatment in children presenting with sleep-disordered breathing (SDB). The main objective of this study was to evaluate the effects of RME on sleep characteristics in children. Polysomnography was done on children of 8-13 years of age before expansion (T0), after expansion (T1) and after a period of 3 months after retention (T2). Bonded rapid maxillary expander was cemented in all children. Inter-molar distance was also measured at T0 and T2. Nonparametric Friedman test was used for comparing the averages of sleep parameters at different time period (T0, T1, T2). Wilcoxon signed ranks test was used for comparing the averages of inter-molar width (T0-T2). P children showed an improvement in sleep parameters with an increase in sleep efficiency, decreased in arousal and desaturation index after expansion. Total sleep time showed a statistically significant increase after expansion. A statistically significant increase in inter-molar distance was obtained after expansion. Rapid maxillary expansion is a useful treatment option for improving quality of sleep even in normal children without SDB. It also induces widening of the maxilla, corrects posterior crossbites and improves maxillary and mandibular dental arch coordination.

  13. [Unilateral surgically assisted rapid maxillary expansion using a transpalatal distractor].

    NARCIS (Netherlands)

    Roelofs, J.; Breuning, K.H.; Spijker, A. van 't; Borstlap, W.A.; Berge, S.J.; Kuijpers-Jagtman, A.M.

    2010-01-01

    A 46-year-old woman was referred for orthodontic surgery consultation because ofa retrognathic maxilla, unilateral cross bite and functional, aesthetic and speech problems. The maxilla was widened unilaterally by unilateral surgically assisted rapid maxillary expansion with a bone-borne transpalatal

  14. Surgically Assisted Rapid Maxillary Expansion: surgical and orthodontic aspects

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    M.J. Koudstaal (Maarten)

    2008-01-01

    textabstractThe scope of this thesis is to shed more light, from a number of perspectives, on surgically assisted rapid maxillary expansion (SARME). The primary questions this thesis set out to answer were; ‘is there a difference in stability between bone-borne and tooth-borne distraction?’ and ‘can

  15. Rapid, global demographic expansions after the origins of agriculture.

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    Gignoux, Christopher R; Henn, Brenna M; Mountain, Joanna L

    2011-04-12

    The invention of agriculture is widely assumed to have driven recent human population growth. However, direct genetic evidence for population growth after independent agricultural origins has been elusive. We estimated population sizes through time from a set of globally distributed whole mitochondrial genomes, after separating lineages associated with agricultural populations from those associated with hunter-gatherers. The coalescent-based analysis revealed strong evidence for distinct demographic expansions in Europe, southeastern Asia, and sub-Saharan Africa within the past 10,000 y. Estimates of the timing of population growth based on genetic data correspond neatly to dates for the initial origins of agriculture derived from archaeological evidence. Comparisons of rates of population growth through time reveal that the invention of agriculture facilitated a fivefold increase in population growth relative to more ancient expansions of hunter-gatherers.

  16. Longitudinal stability of rapid and slow maxillary expansion

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    Fábio Henrique de Sá Leitão Pinheiro

    2014-12-01

    Full Text Available OBJECTIVE: The aim of this retrospective study was to compare the longitudinal stability of two types of posterior crossbite correction: rapid maxillary expansion (RME and slow maxillary expansion (SME.METHODS: Study casts of 90 adolescent patients were assessed for interdental width changes at three different periods: pretreatment (T1, post-treatment (T2 and at least, five years post-retention (T3. Three groups of 30 patients were established according to the treatment received to correct posterior crossbite: Group A (RME, group B (SME and group C (control- Edgewise therapy only. After crossbite correction, all patients received fixed edgewise orthodontic appliances. Paired t-tests and one-way ANOVA were used to identify significant intra and intergroup changes, respectively (P < 0.05.RESULTS: Except for intercanine distance, all widths increased in groups A and B from T1 to T2. In the long-term, the amount of relapse was not different for groups A and B, except for 3-3 widths which showed greater decrease in group A. However, the percentage of clinically relapsed cases of posterior crossbite was similar for rapid and slow maxillary expansion.CONCLUSION: Rapid and slow maxillary expansion showed similar stability in the long-term.

  17. Surgically assisted rapid palatal expansion: a literature review.

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    Suri, Lokesh; Taneja, Parul

    2008-02-01

    Transverse maxillomandibular discrepancies are a major component of several malocclusions. Orthopedic and orthodontic forces are used routinely to correct a maxillary transverse deficiency (MTD) in a young patient. Correction of MTD in a skeletally mature patient is more challenging because of changes in the osseous articulations of the maxilla with the adjoining bones. Surgically assisted rapid palatal expansion (SARPE) has gradually gained popularity as a treatment option to correct MTD. It allows clinicians to achieve effective maxillary expansion in a skeletally mature patient. The use of SARPE to treat MTD decreases unwanted effects of orthopedic or orthodontic expansion. Our aim in this article is to present a comprehensive review of the literature, including indications, diagnosis, guidelines for case selection, a brief overview of the surgical techniques, orthodontic considerations, complications, risks, and limitations of SARPE to better aid the clinician in the management of MTD in skeletally mature patients.

  18. Population Genetics of Three Dimensional Range Expansions

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    Lavrentovich, Maxim; Nelson, David

    2014-03-01

    We develop a simple model of genetic diversity in growing spherical cell clusters, where the growth is confined to the cluster surface. This kind of growth occurs in cells growing in soft agar, and can also serve as a simple model of avascular tumors. Mutation-selection balance in these radial expansions is strongly influenced by scaling near a neutral, voter model critical point and by the inflating frontier. We develop a scaling theory to describe how the dynamics of mutation-selection balance is cut off by inflation. Genetic drift, i.e., local fluctuations in the genetic diversity, also plays an important role, and can lead to the extinction even of selectively advantageous strains. We calculate this extinction probability, taking into account the effect of rough population frontiers.

  19. Management of recurrent otitis media with rapid maxillary expansion: our experience.

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    De Stefano, A; Baffa, C; Cerrone, D; Mathur, N; Cascini, V; Petrucci, A G; Neri, G

    2009-01-01

    Management of recurrent otitis media with rapid maxillary expansion: our experience. Recurrent otitis media is a frequent problem in the paediatric population. It is commonly associated with adenoid hypertrophy and occasionally with skeletal development syndrome characterised by maxillary anatomical alterations. When this syndrome is present in conjunction with adenoid hypertrophy, surgical management with adenoidectomy and/or myringotomy with ventilation tube positioning does not necessarily ensure a resolution of conductive hearing disorders. We used maxillary rapid expansion in 27 children with a mean age of 7 years affected by recurrent otitis media associated with skeletal development syndrome and adenoid hypertrophy. Rapid maxillary expansion acting directly on the median palatine suture expands the palate and the nasal floor, improving nasal breathing. In addition, maxillary expansion stretches elevator and tensor palatine muscles, helping to restore normal Eustachian tube function, even in the presence of adenoid hypertrophy. In our opinion, rapid maxillary expansion results in an improvement in skeletal-facial abnormalities associated with skeletal development syndrome and it can be considered a valid treatment for preventing recurrent otitis media in children affected by maxillary anatomical alterations.

  20. Effects of rapid maxillary expansion on nasal mucociliary clearance.

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    Babacan, Hasan; Doruk, Cenk; Uysal, Ismail Onder; Yuce, Salim

    2016-03-01

    To evaluate the changes in nasal mucociliary clearance in orthodontic patients after rapid maxillary expansion (RME) therapy. Forty-two children (25 boys and 17 girls) participated in this study. The RME group consisted of 21 patients (mean age, 13.8 years), who had undergone RME at the initiation of orthodontic treatment. The control group consisted of 21 subjects (mean age, 13.6 years), who were attending the department of orthodontics for active orthodontic treatment. The nasal mucociliary clearance was assessed by the saccharin test. Saccharin transit times (STTs) were measured for each treated subject before expansion (T1), after RME (T2), and after a 3-month retention period (T3). Records were obtained at the same time intervals for each group. The STT decreased significantly in the RME group after expansion and retention (P expansion and retention (P maxillary narrowness and without any history of nasal or systemic disease were within normal limits. However, RME increased the mucociliary clearance in patients who had maxillary narrowness, having positive effects on nasal physiology and increasing nasal cavity volume.

  1. The thermospheric effects of a rapid polar cap expansion

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    D. W. Idenden

    Full Text Available In a previous publication we used results from a coupled thermosphere-ionosphere-plasmasphere model to illustrate a new mechanism for the formation of a large-scale patch of ionisation arising from a rapid polar cap expansion. Here we describe the thermospheric response to that polar cap expansion, and to the ionospheric structure produced. The response is dominated by the energy and momentum input at the dayside throat during the expansion phase itself. These inputs give rise to a large-scale travelling atmospheric disturbance (TAD that propagates both antisunward across the polar cap and equatorward at speeds much greater than both the ion drifts and the neutral winds. We concentrate only on the initially poleward travelling disturbance. The disturbance is manifested in the neutral temperature and wind fields, the height of the pressure level surfaces and in the neutral density at fixed heights. The thermospheric effects caused by the ionospheric structure produced during the expansion are hard to discern due to the dominating effects of the TAD.

    Key words. Ionosphere (ionosphere · atmosphere interaction; modeling and forecasting; plasma convection.

  2. The thermospheric effects of a rapid polar cap expansion

    Directory of Open Access Journals (Sweden)

    D. W. Idenden

    1998-10-01

    Full Text Available In a previous publication we used results from a coupled thermosphere-ionosphere-plasmasphere model to illustrate a new mechanism for the formation of a large-scale patch of ionisation arising from a rapid polar cap expansion. Here we describe the thermospheric response to that polar cap expansion, and to the ionospheric structure produced. The response is dominated by the energy and momentum input at the dayside throat during the expansion phase itself. These inputs give rise to a large-scale travelling atmospheric disturbance (TAD that propagates both antisunward across the polar cap and equatorward at speeds much greater than both the ion drifts and the neutral winds. We concentrate only on the initially poleward travelling disturbance. The disturbance is manifested in the neutral temperature and wind fields, the height of the pressure level surfaces and in the neutral density at fixed heights. The thermospheric effects caused by the ionospheric structure produced during the expansion are hard to discern due to the dominating effects of the TAD.Key words. Ionosphere (ionosphere · atmosphere interaction; modeling and forecasting; plasma convection.

  3. eRME - Rapid Maxillary Expansion in the economic way

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    Sonali Mahadevia

    2011-01-01

    Full Text Available Aim and Objectives: Rapid Maxillary Expansion constitutes a routine clinical procedure in orthodontics, involving separation of mid-palatine suture which is usually done with help of the Hyrax screw. However, because of its high cost, the use has been limited, especially in institutions. So, the purpose of this study was to construct an economical device which can expand the maxillary arch in growing patients. Materials and Methods: Six patients having constricted maxilla and posterior skeletal crossbite were randomly selected from the Department of Orthodontics. A unique, easy and simple alternative device for expanding the maxillary arch called economic Rapid Maxillary Expander (eRME has been fabricated at about one-tenth the cost of the conventional Hyrax. Pre- and post-treatment effects were statistically tested by using paired t-test at 0.05 level of significance. Results and Conclusion: The study results showed an average expansion in canine, premolar and molar regions of 4.4 mm, 6.8 mm and 9.4 mm, respectively, having significant difference pre-and post-treatment. Thus, it shows that maxillary expansion is efficiently possible with the application of this newly constructed device named eRME. This appliance also acts as a fixed retainer to avoid relapse, hence negating the need for a separate retainer.

  4. Rapid palatal expansion: a comparison of two appliances

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    Amanda do Prado Rodrigues

    2012-06-01

    Full Text Available This study analyzed occlusal radiographs to compare the transverse changes produced in patients treated with rapid maxillary expansion using two types of appliances. The sample consisted of 31 children aged 7 to 10.6 years, of both genders, with posterior cross-bite. Fifteen children were treated with a tooth-borne expander and 16 were treated with a tooth-tissue-borne expander. Occlusal radiographs obtained at treatment onset and at the end of the retention period were digitized. The following variables were measured: intermolar distance (IMD, interapical distance (IApD, interbase distance (IBaD and interarm distance (IArD. The results revealed increases in all measurements in both groups after rapid maxillary expansion. Comparison between groups revealed that the increases were greater in patients treated with the tooth-borne expander, except for the IArD measurement, which presented the same increase in both groups. Even though the IMD measurements differed between expanders, they were proportional to the activation of the appliances (IBaD. The increase in the IApD measurement was proportionally greater in the group treated with the tooth-borne expander (0.7:1.0 than in that treated with the tooth-tissue-borne expander (0.4:1.0. It was concluded that both appliances had similar effects, although the tooth-tissue-borne expander produced a lesser opening at the apical region of the incisors.

  5. Alveolar bone changes after asymmetric rapid maxillary expansion.

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    Akin, Mehmet; Baka, Zeliha Muge; Ileri, Zehra; Basciftci, Faruk Ayhan

    2015-09-01

    To quantitatively evaluate the effects of asymmetric rapid maxillary expansion (ARME) on cortical bone thickness and buccal alveolar bone height (BABH), and to determine the formation of dehiscence and fenestration in the alveolar bone surrounding the posterior teeth, using cone-beam computed tomography (CBCT). The CBCT records of 23 patients with true unilateral posterior skeletal crossbite (10 boys, 14.06 ± 1.08 years old, and 13 girls, 13.64 ± 1.32 years old) who had undergone ARME were selected from our clinic archives. The bonded acrylic ARME appliance, including an occlusal stopper, was used on all patients. CBCT records had been taken before ARME (T1) and after the 3-month retention period (T2). Axial slices of the CBCT images at 3 vertical levels were used to evaluate the buccal and palatal aspects of the canines, first and second premolars, and first molars. Paired samples and independent sample t-tests were used for statistical comparison. The results suggest that buccal cortical bone thickness of the affected side was significantly more affected by the expansion than was the unaffected side (P ARME significantly reduced the BABH of the canines (P ARME also increased the incidence of dehiscence and fenestration on the affected side. ARME may quantitatively decrease buccal cortical bone thickness and height on the affected side.

  6. The Population Origins and Expansion of Feral Cats in Australia.

    Science.gov (United States)

    Spencer, Peter B S; Yurchenko, Andrey A; David, Victor A; Scott, Rachael; Koepfli, Klaus-Peter; Driscoll, Carlos; O'Brien, Stephen J; Menotti-Raymond, Marilyn

    2016-03-01

    The historical literature suggests that in Australia, the domestic cat (Felis catus) had a European origin [~200 years before present (ybp)], but it is unclear if cats arrived from across the Asian land bridge contemporaneously with the dingo (4000 ybp), or perhaps immigrated ~40000 ybp in association with Aboriginal settlement from Asia. The origin of cats in Australia is important because the continent has a complex and ancient faunal assemblage that is dominated by endemic rodents and marsupials and lacks the large placental carnivores found on other large continents. Cats are now ubiquitous across the entire Australian continent and have been implicit in the range contraction or extinction of its small to medium sized (Australia exhibit high genetic diversity in comparison with the low diversity found in populations of feral cats living on islands. The genetic structure is consistent with a rapid westerly expansion from eastern Australia and a limited expansion in coastal Western Australia. Australian cats show modest if any population structure and a close genetic alignment with European feral cats as compared to cats from Asia, the Christmas and Cocos (Keeling) Islands (Indian Ocean), and European wildcats (F. silvestris silvestris). © The American Genetic Association 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. Photographic assessment of nasal morphology following rapid maxillary expansion in children

    OpenAIRE

    Omar Gabriel da Silva Filho; Tulio Silva Lara; Priscila Vaz Ayub; Amanda Sayuri Cardoso Ohashi; Francisco Antônio Bertoz

    2011-01-01

    Objective: The aim of the present study was to use facial analysis to determine the effects of rapid maxillary expansion (RME) on nasal morphology in children in the stages of primary and mixed dentition, with posterior cross-bite. Material and Methods: Facial photographs (front view and profile) of 60 patients in the pre-expansion period, immediate post-expansion period and one year following rapid maxillary expansion with a Haas appliance were evaluated on 2 occasions by 3 experienced ortho...

  8. Rapid replacement of bridge deck expansion joints study - phase I.

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    2014-12-01

    Bridge deck expansion joints are used to allow for movement of the bridge deck due to thermal expansion, dynamics loading, and : other factors. More recently, expansion joints have also been utilized to prevent the passage of winter de-icing chemical...

  9. Evaluation of immediate soft tissue changes after rapid maxillary expansion

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    Ki Beom Kim

    2012-10-01

    Full Text Available OBJECTIVE: To evaluate immediate soft tissue changes following rapid maxillary expansion (RME in growing patients, using cone beam computed tomography (CBCT. METHODS: Twenty-three consecutive patients (10 male, 13 female treated by RME were selected. Patients were scanned using CBCT prior to placement of the rapid maxillary expander (T0, then immediately following full activation of the appliance (T1. Defined landmarks were then located on the pre- and post-treatment orientated images. Change in landmark position from pre- to post-treatment was then measured. In addition to landmarks, 10 direct measures were made to determine distance change without regard to direction to measure soft tissue change of the lips. RESULTS: Significant transverse expansion was measured on most soft tissue landmark locations. All the measures made showed significant change in the lip position with a lengthening of the vertical dimension of the upper lip, and a generalized decrease of anterior-posterior thickness of both the upper and lower lips. CONCLUSIONS: Significant changes in the soft tissue do occur with RME treatment. There is a transverse widening of the midface, and a thinning of the lips.OBJETIVO: avaliar as mudanças imediatas no tecido mole após a expansão rápida da maxila (ERM em pacientes em fase de crescimento, usando tomografia computadorizada de feixe cônico (TCFC. MÉTODOS: vinte e três pacientes (10 do sexo masculino e 13 do feminino tratados com ERM foram selecionados. Os pacientes foram escaneados por TCFC antes da implantação do expansor maxilar (T0 e imediatamente após a completa ativação do aparelho (T1. Pontos cefalométricos definidos foram localizados nas imagens pré- e pós-tratamento. As mudanças de posição desses pontos do pré- para o pós-tratamento foram, então, analisadas. Adicionalmente aos pontos, 10 medições diretas foram realizadas para determinar a mudança nas distâncias - independentemente da direção - nos

  10. Transverse Expansion and Stability after Segmental Le Fort I Osteotomy versus Surgically Assisted Rapid Maxillary Expansion: a Systematic Review

    Directory of Open Access Journals (Sweden)

    Thomas Starch-Jensen

    2017-01-01

    Full Text Available Objectives: The objective of the present systematic review was to test the hypothesis of no difference in transverse skeletal and dental arch expansion and relapse after segmental Le Fort I osteotomy versus surgically assisted rapid maxillary expansion. Material and Methods: A MEDLINE (PubMed, Embase and Cochrane library search in combination with a hand-search of relevant journals was conducted by including human studies published in English from January 1, 2000 to June 1, 2016. Results: The search provided 130 titles and four studies fulfilled the inclusion criteria. All the included studies were characterized by high risk of bias and meta-analysis was not possible due to considerable variation. Both treatment modalities significantly increase the transverse maxillary skeletal and dental arch width. The transverse dental arch expansion and relapse seems to be substantial higher with tooth-borne surgically assisted rapid maxillary expansion compared to segmental Le Fort I osteotomy. The ratio of dental to skeletal relapse was significantly higher in the posterior maxilla with tooth-borne surgically assisted rapid maxillary expansion. Moreover, a parallel opening without segment tilting was observed after segmental Le Fort I osteotomy. Conclusions: Maxillary transverse deficiency in adults can be treated successfully with both treatment modalities, although surgically assisted rapid maxillary expansion seems more effective when large transverse maxillary skeletal and dental arch expansion is required. However, considering the methodological limitations of the included studies, long-term randomized studies assessing transverse skeletal and dental expansion and relapse with the two treatment modalities are needed before definite conclusions can be provided.

  11. Rapid maxillary expansion treatment could produce long-term dental arch changes

    NARCIS (Netherlands)

    Ren, Yijin

    2005-01-01

    : Data Sources: Medline, Medline In-Process, LILACS (Latin American and Caribbean Health Sciences Literature), PUBMED, Embase, Web of Science and the Cochrane Library were searched. Search terms were rapid palatal expansion or rapid maxillary expansion (RME) and tooth or dental changes. Reference

  12. Following Surgically Assisted Rapid Palatal Expansion, Do Tooth-Borne or Bone-Borne Appliances Provide More Skeletal Expansion and Dental Expansion?

    Science.gov (United States)

    Hamedi-Sangsari, Adrien; Chinipardaz, Zahra; Carrasco, Lee

    2017-10-01

    The aim of this study was to compare outcome measurements of skeletal and dental expansion with bone-borne (BB) versus tooth-borne (TB) appliances after surgically assisted rapid palatal expansion (SARPE). This study was performed to provide quantitative measurements that will help the oral surgeon and orthodontist in selecting the appliance with, on average, the greatest amount of skeletal expansion and the least amount of dental expansion. A computerized database search was performed using PubMed, EBSCO, Cochrane, Scopus, Web of Science, and Google Scholar on publications in reputable oral surgery and orthodontic journals. A systematic review and meta-analysis was completed with the predictor variable of expansion appliance (TB vs BB) and outcome measurement of expansion (in millimeters). Of 487 articles retrieved from the 6 databases, 5 articles were included, 4 with cone-beam computed tomographic (CBCT) data and 1 with non-CBCT 3-dimensional cast data. There was a significant difference in skeletal expansion (standardized mean difference [SMD], 0.92; 95% confidence interval [CI], 0.54-1.30; P < .001) in favor of BB rather than TB appliances. However, there was no significant difference in dental expansion (SMD, 0.05; 95% CI, -0.24 to 0.34; P = .03). According to the literature, to achieve more effective skeletal expansion and minimize dental expansion after SARPE, a BB appliance should be favored. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  13. Assessment of changes in smile after rapid maxillary expansion

    Directory of Open Access Journals (Sweden)

    Ana Paula Morales Cobra de Carvalho

    2012-10-01

    Full Text Available INTRODUCTION: This study evaluated changes in the smile characteristics of patients with maxillary constriction submitted to rapid maxillary expansion (RME. METHODS: The sample consisted of 81 extraoral photographs of maximum smile of 27 patients with mean age of 10 years, before expansion and 3 and 6 months after fixation of the expanding screw. The photographs were analyzed on the software Cef X 2001, with achievement of the following measurements: Transverse smile area, buccal corridors, exposure of maxillary incisors, gingival exposure of maxillary incisors, smile height, upper and lower lip thickness, smile symmetry and smile arch. Statistical analysis was performed by analysis of variance (ANOVA, at a significance level of 5%. RESULTS: RME promoted statistically significant increase in the transverse smile dimension and exposure of maxillary central and lateral incisors; maintenance of right and left side smile symmetry and of the lack of parallelism between the curvature of the maxillary incisal edges and lower lip border. CONCLUSIONS: RME was beneficial for the smile esthetics with the increase of the transverse smile dimension and exposure of maxillary central and lateral incisors.INTRODUÇÃO: esse estudo avaliou as alterações das características do sorriso de pacientes com atresia maxilar submetidos à expansão rápida da maxila (ERM. MÉTODOS: a amostra consistiu de 81 fotografias extrabucais do sorriso máximo de 27 pacientes, com idade média de 10 anos, antes da expansão e aos três e seis meses após a fixação do parafuso expansor. As análises das fotografias foram realizadas por meio do programa Cef X 2001, e as seguintes medidas foram analisadas: dimensão transversal do sorriso, corredores bucais, quantidade de exposição dos incisivos superiores, exposição gengival dos incisivos superiores, altura do sorriso, espessuras dos lábios superior e inferior, simetria e arco do sorriso. As alterações no sorriso durante

  14. The nexus of population change, agricultural expansion, landscape ...

    African Journals Online (AJOL)

    It reveals the pattern of change in landscape and how that corresponds to human factors such as increased population, demand for food and consequent expansion in agricultural activity in the modification of Landscape. The period under consideration (1970-2007) witnessed an increase in population size and household ...

  15. The effect of rapid palatal expansion on sleep bruxism in children.

    Science.gov (United States)

    Bellerive, Audrey; Montpetit, Andrée; El-Khatib, Hicham; Carra, Maria Clotilde; Remise, Claude; Desplats, Eve; Huynh, Nelly

    2015-12-01

    Sleep bruxism (SB) is a movement described as an involuntary mastication movement during sleep, also defined as rhythmic masticatory muscle activity (RMMA). It is observed in 2-40 % of the pediatric population. A link was suggested between respiratory events and RMMA. Rapid palatal expansion (RPE) is an effective orthopedic treatment for correcting maxillary transverse deficiency and sleep-disordered breathing (SDB) in children. The aim was to evaluate the possible reduction of SB after rapid palatal expansion (RPE) therapy. A total of 32 patients (8-14 years old; 22 girls and 10 boys) received an orthodontic treatment for transverse maxillary deficiency (5 mm or more) at the orthodontics department of the Université de Montréal. They underwent an ambulatory polysomnography (PSG) before, after expansion with the expander, and at the end of the study without the expander. They were classified into three subgroups based on sleep electromyography (EMG) data. Total sleep time and stage NREM 3 presented significant differences between the types of appliances. Moreover, there was a time effect observed for total sleep time, sleep cycles, stage NREM 2, and stage REM, while only a trend suggested for stage NREM 3. Significant differences were observed between subgroups for both RMMA episodes and burst indexes, similarly, for the oxygen desaturation index (ODI). A total of 50 % of the patients were classified as responders when RMMA episodes index decreased by more than 25 % when comparing treatment efficacy at baseline night. Most bruxers (65 %) reduced their RMMA episode index after expansion, but sleep and respiratory variables remained unchanged.

  16. Genetic variation reveals large-scale population expansion and migration during the expansion of Bantu-speaking peoples.

    Science.gov (United States)

    Li, Sen; Schlebusch, Carina; Jakobsson, Mattias

    2014-10-22

    The majority of sub-Saharan Africans today speak a number of closely related languages collectively referred to as 'Bantu' languages. The current distribution of Bantu-speaking populations has been found to largely be a consequence of the movement of people rather than a diffusion of language alone. Linguistic and single marker genetic studies have generated various hypotheses regarding the timing and the routes of the Bantu expansion, but these hypotheses have not been thoroughly investigated. In this study, we re-analysed microsatellite markers typed for large number of African populations that-owing to their fast mutation rates-capture signatures of recent population history. We confirm the spread of west African people across most of sub-Saharan Africa and estimated the expansion of Bantu-speaking groups, using a Bayesian approach, to around 5600 years ago. We tested four different divergence models for Bantu-speaking populations with a distribution comprising three geographical regions in Africa. We found that the most likely model for the movement of the eastern branch of Bantu-speakers involves migration of Bantu-speaking groups to the east followed by migration to the south. This model, however, is only marginally more likely than other models, which might indicate direct movement from the west and/or significant gene flow with the western Branch of Bantu-speakers. Our study use multi-loci genetic data to explicitly investigate the timing and mode of the Bantu expansion and it demonstrates that west African groups rapidly expanded both in numbers and over a large geographical area, affirming the fact that the Bantu expansion was one of the most dramatic demographic events in human history.

  17. Rapid evolution and range expansion of an invasive plant are driven by provenance-environment interactions.

    Science.gov (United States)

    Zenni, Rafael D; Bailey, Joseph K; Simberloff, Daniel

    2014-06-01

    To improve our ability to prevent and manage biological invasions, we must understand their ecological and evolutionary drivers. We are often able to explain invasions after they happen, but our predictive ability is limited. Here, we show that range expansions of introduced Pinus taeda result from an interaction between genetic provenance and climate and that temperature and precipitation clines predict the invasive performance of particular provenances. Furthermore, we show that genotypes can occupy climate niche spaces different from those observed in their native ranges and, at least in our case, that admixture is not a main driver of invasion. Genotypes respond to climate in distinct ways, and these interactions affect the ability of populations to expand their ranges. While rapid evolution in introduced ranges is a mechanism at later stages of the invasion process, the introduction of adapted genotypes is a key driver of naturalisation of populations of introduced species. © 2014 John Wiley & Sons Ltd/CNRS.

  18. Population growth, urban expansion, and private forestry in western Oregon.

    Science.gov (United States)

    Jeffrey D. Kline; David L. Azuma; Ralph J. Alig

    2004-01-01

    Private forestlands in the United States face increasing pressures from growing populations, resulting in greater numbers of people living in closer proximity to forests. What often is called the "wildland/urban interface" is characterized by expansion of residential and other developed land uses onto forested landscapes in a manner that threatens forestlands...

  19. Mangrove expansion and population structure at a planted site, East ...

    African Journals Online (AJOL)

    The expansion of mangroves was measured using past aerial photographs and Esri ArcGIS Desktop 10 software. In addition, field surveys were completed in 2011 to determine the population structure of the present mangrove forest and relate this to environmental conditions. The study showed that mangrove area cover ...

  20. Photographic assessment of nasal morphology following rapid maxillary expansion in children

    Directory of Open Access Journals (Sweden)

    Omar Gabriel da Silva Filho

    2011-10-01

    Full Text Available OBJECTIVE: The aim of the present study was to use facial analysis to determine the effects of rapid maxillary expansion (RME on nasal morphology in children in the stages of primary and mixed dentition, with posterior cross-bite. MATERIAL AND METHODS: Facial photographs (front view and profile of 60 patients in the pre-expansion period, immediate post-expansion period and one year following rapid maxillary expansion with a Haas appliance were evaluated on 2 occasions by 3 experienced orthodontists independently, with a 2-week interval between evaluations. The examiners were instructed to assess nasal morphology and had no knowledge regarding the content of the study. Intraexaminer and interexaminer agreement (assessed using the Kappa statistic was acceptable. RESULTS: From the analysis of the mode of the examiners' findings, no alterations in nasal morphology occurred regarding the following aspects: dorsum of nose, alar base, nasal width of middle third and nasal base. Alterations were only detected in the nasolabial angle in 1.64% of the patients between the pre-expansion and immediate post-expansion photographs. In 4.92% of the patients between the immediate post-expansion period and 1 year following expansion; and in 6.56% of the patients between the pre-expansion period and one year following expansion. CONCLUSIONS: RME performed on children in stages of primary and mixed dentition did not have any impact on nasal morphology, as assessed using facial analysis.

  1. Photographic assessment of nasal morphology following rapid maxillary expansion in children

    Science.gov (United States)

    da SILVA FILHO, Omar Gabriel; LARA, Tulio Silva; AYUB, Priscila Vaz; OHASHI, Amanda Sayuri Cardoso; BERTOZ, Francisco Antônio

    2011-01-01

    Objective The aim of the present study was to use facial analysis to determine the effects of rapid maxillary expansion (RME) on nasal morphology in children in the stages of primary and mixed dentition, with posterior cross-bite. Material and Methods Facial photographs (front view and profile) of 60 patients in the pre-expansion period, immediate post-expansion period and one year following rapid maxillary expansion with a Haas appliance were evaluated on 2 occasions by 3 experienced orthodontists independently, with a 2-week interval between evaluations. The examiners were instructed to assess nasal morphology and had no knowledge regarding the content of the study. Intraexaminer and interexaminer agreement (assessed using the Kappa statistic) was acceptable. Results From the analysis of the mode of the examiners' findings, no alterations in nasal morphology occurred regarding the following aspects: dorsum of nose, alar base, nasal width of middle third and nasal base. Alterations were only detected in the nasolabial angle in 1.64% of the patients between the pre-expansion and immediate post-expansion photographs. In 4.92% of the patients between the immediate post-expansion period and 1 year following expansion; and in 6.56% of the patients between the pre-expansion period and one year following expansion. Conclusion RME performed on children in stages of primary and mixed dentition did not have any impact on nasal morphology, as assessed using facial analysis. PMID:21986660

  2. Rapid divergence and expansion of the X chromosome in papaya

    Science.gov (United States)

    Gschwend, Andrea R.; Yu, Qingyi; Tong, Eric J.; Zeng, Fanchang; Han, Jennifer; VanBuren, Robert; Aryal, Rishi; Charlesworth, Deborah; Moore, Paul H.; Paterson, Andrew H.; Ming, Ray

    2012-01-01

    X chromosomes have long been thought to conserve the structure and gene content of the ancestral autosome from which the sex chromosomes evolved. We compared the recently evolved papaya sex chromosomes with a homologous autosome of a close relative, the monoecious Vasconcellea monoica, to infer changes since recombination stopped between the papaya sex chromosomes. We sequenced 12 V. monoica bacterial artificial chromosomes, 11 corresponding to the papaya X-specific region, and 1 to a papaya autosomal region. The combined V. monoica X-orthologous sequences are much shorter (1.10 Mb) than the corresponding papaya region (2.56 Mb). Given that the V. monoica genome is 41% larger than that of papaya, this finding suggests considerable expansion of the papaya X; expansion is supported by a higher repetitive sequence content of the X compared with the papaya autosomal sequence. The alignable regions include 27 transcript-encoding sequences, only 6 of which are functional X/V. monoica gene pairs. Sequence divergence from the V. monoica orthologs is almost identical for papaya X and Y alleles; the Carica-Vasconcellea split therefore occurred before the papaya sex chromosomes stopped recombining, making V. monoica a suitable outgroup for inferring changes in papaya sex chromosomes. The papaya X and the hermaphrodite-specific region of the Yh chromosome and V. monoica have all gained and lost genes, including a surprising amount of changes in the X. PMID:22869742

  3. Empirical and mathematical model of rapid expansion of supercritical solution (RESS) process of acetaminophen

    Science.gov (United States)

    Kien, Le Anh

    2017-09-01

    Rapid Expansion of Supercritical Solutions (RESS) is a solvent-free technology to produce small solid particles with very narrow size distribution. RESS process is simple and easy to control in comparison with other methods based on supercritical techniques. In this study, the engineering of nano (or submicron) acetaminophen particles using rapid expansion CO2 supercritical solution (RESS) was investigated. Empirical model with response surface methodology was used to evaluate the effects of processing parameters, i.e. extraction temperature T (313-333 K), extraction pressure P (90-150 bar) and pre-expansion temperature Texp (353-373 K), on the size of precipitated acetaminophen particles. The results show that the smallest particle size, i.e. 52.08 nm can be achieved at 90 bar, 313 K and 353 K (P, T, Texp, respectively). To better understand and develop a mechanistic predictive tool for RESS process, a one dimensional steady flow model was used in this work to describe the subsonic expansion process inside the capillary nozzle and the supersonic expansion process outside expansion nozzle. It was shown that particle characteristics are governed by both operation parameters such as pre-expansion temperature, pre-expansion pressure, and expansion temperature. These parameters affects particle size in the same trend as that was found from experiment data and empirical model.

  4. Laser and LED phototherapy on midpalatal suture after rapid maxilla expansion: Raman and histological analysis.

    Science.gov (United States)

    Rosa, Cristiane Becher; Habib, Fernando Antonio Lima; de Araújo, Telma Martins; Dos Santos, Jean Nunes; Cangussu, Maria Cristina T; Barbosa, Artur Felipe Santos; de Castro, Isabele Cardoso Vieira; Pinheiro, Antônio Luiz Barbosa

    2017-02-01

    The aim of this study was to analyze the effect of laser or LED phototherapy on the acceleration of bone formation at the midpalatal suture after rapid maxilla expansion. Forty-five rats were divided into groups at 7 days (control, expansion, expansion and laser irradiation, and expansion and LED irradiation) and into 14 days (expansion, expansion and laser in the 1st week, expansion and LED in the 1st week, expansion and laser in the 1st and 2nd weeks, expansion and LED in the 1st and 2nd weeks). Laser/LED irradiation occurred every 48 h. Expansion was accomplished with a spatula and maintained with a triple helicoid of 0.020-in stainless steel orthodontic wire. A diode laser (λ780 nm, 70 mW, spot of 0.04 cm2, t = 257 s, SAEF of 18 J/cm2) or a LED (λ850 ± 10 nm, 150 ± 10 mW, spot of 0.5 cm2, t = 120 s, SAEF of 18 J/cm2) was applied in one point in the midpalatal suture immediately behind the upper incisors. Raman spectroscopy and histological analyses of the suture region were carried and data was submitted to statistical analyses (p ≤ 0.05). Raman spectrum analysis demonstrated that irradiation increases hydroxyapatite in the midpalatal suture after expansion. In the histological analysis of various inflammation, there was a higher production of collagen and osteoblastic activity and less osteoclastic activity. The results showed that LED irradiation associated to rapid maxillary expansion improves bone repair and could be an alternative to the use of laser in accelerating bone formation in the midpalatal suture.

  5. Rapid Maxillary Expansion Increases Internal Nasal Dimensions of Children With Bilateral Cleft Lip and Palate.

    Science.gov (United States)

    Trindade-Suedam, Ivy Kiemle; Castilho, Ricardo Leão; Sampaio-Teixeira, Ana Claudia Martins; Araújo, Bruna Mara Adorno Marmotel; Fukushiro, Ana Paula; Campos, Letícia Dominguez; Trindade, Inge Elly Kiemle

    2016-05-01

    The transverse maxillary deficiency frequently observed in patients with cleft lip and palate (CLP) is usually treated by rapid maxillary expansion (RME). Considering that RME causes a significant increase of the internal nasal dimensions in children with unilateral CLP (UCLP), this study aimed to characterize the internal nasal geometry of children with bilateral CLP (BCLP) and transverse maxillary deficiency using acoustic rhinometry. The study also aimed to analyze changes caused by RME. Cross-sectional prospective study. Laboratory of Physiology, Hospital for Rehabilitation of Craniofacial Anomalies, University of São Paulo, Bauru, SP, Brazil. Fifteen children with repaired BCLP of both genders, aged 8 to 15 years, referred for RME, were prospectively analyzed. Subjects underwent acoustic rhinometry before the expander installation and after the active phase of expansion. Cross-sectional areas (CSA) and volumes (V) of the nasal valve regions (CSA1 and V1) and turbinates (CSA2, CSA3, and V2), were measured after nasal decongestion. In the majority of the subjects, an increase of internal nasal dimensions was observed. Percent changes of CSA1, CSA2, CSA3, V1, and V2 were: +25%, +11%, +9%, 20%, and +12%, respectively. Differences were significant for all variables studied, except CSA3 (P < .05). RME promotes an increase in the internal nasal dimensions of children with BCLP, suggesting that RME is capable of substantially improving nasal patency in this population.

  6. Genetic mixture of multiple source populations accelerates invasive range expansion.

    Science.gov (United States)

    Wagner, Natalie K; Ochocki, Brad M; Crawford, Kerri M; Compagnoni, Aldo; Miller, Tom E X

    2017-01-01

    A wealth of population genetic studies have documented that many successful biological invasions stem from multiple introductions from genetically distinct source populations. Yet, mechanistic understanding of whether and how genetic mixture promotes invasiveness has lagged behind documentation that such mixture commonly occurs. We conducted a laboratory experiment to test the influence of genetic mixture on the velocity of invasive range expansion. The mechanistic basis for effects of genetic mixture could include evolutionary responses (mixed invasions may harbour greater genetic diversity and thus elevated evolutionary potential) and/or fitness advantages of between-population mating (heterosis). If driven by evolution, positive effects of source population mixture should increase through time, as selection sculpts genetic variation. If driven by heterosis, effects of mixture should peak following first reproductive contact and then dissipate. Using a laboratory model system (beetles spreading through artificial landscapes), we quantified the velocity of range expansion for invasions initiated with one, two, four or six genetic sources over six generations. Our experiment was designed to test predictions corresponding to the evolutionary and heterosis mechanisms, asking whether any effects of genetic mixture occurred in early or later generations of range expansion. We also quantified demography and dispersal for each experimental treatment, since any effects of mixture should be manifest in one or both of these traits. Over six generations, invasions with any amount of genetic mixture (two, four and six sources) spread farther than single-source invasions. Our data suggest that heterosis provided a 'catapult effect', leaving a lasting signature on range expansion even though the benefits of outcrossing were transient. Individual-level trait data indicated that genetic mixture had positive effects on local demography (reduced extinction risk and enhanced

  7. Changes in nasal volume of patients undergoing rapid maxillary expansion

    OpenAIRE

    Muniz, Renata Da Fonseca Lacerda E; Mario Cappellette Jr.; Daniela Carlini

    2008-01-01

    Os efeitos da disjunção maxilar na resistência nasal e fluxo aéreo têm sido amplamente discutidos na literatura, com controvérsias. Suas indicações esqueléticas e dentárias parecem estar bem claras. Porém, aquelas puramente rinológicas não são justificadas, porque nem sempre resultados positivos são encontrados. Este estudo teve por finalidade avaliar a repercussão da disjunção maxilar ortopédica no aspecto respiratório e rinológico dos pacientes submetidos a esse procedimento.Rapid maxillary...

  8. Effect of a rapid maxillary expansion on snoring and sleep in children: a pilot study.

    Science.gov (United States)

    Giannasi, Lilian Chrystiane; Santos, Israel Reis; Alfaya, Thays Almeida; Bussadori, Sandra Kalil; Leitão-Filho, Fernando Studart; de Oliveira, Luis Vicente Franco

    2015-07-01

    The aim of this study was to assess the efficacy of the McNamara rapid palatal expansion device for the treatment of sleep disorders in children. The sample enrolled 12 children aged 4-11 years. Children with snoring and bruxism whose parents did not agree to tonsil surgery were included in the study. During the initial evaluation, a questionnaire addressing sleep was administered, and plaster models were made for the construction of the McNamara rapid maxillary expansion device. The expansion period was 7-15 days, and the McNamara device was removed after 6-8 months. The same questionnaire was administered again after 30 days of use of the orthopedic appliance. The data were analyzed using the McNemar test, with the level of significance set to 5% (Pmaxillary expansion, can be an effective treatment for snoring and other undesirable sleep behaviors in children.

  9. Position and stability of the mandibular incisors after rapid maxillary expansion

    Directory of Open Access Journals (Sweden)

    Darcy Flávio Nouer

    Full Text Available Objective: To make a cephalometric evaluation of the position and stability of the mandibular incisors immediately after rapid maxillaryexpansion and after a containment period of five months. Methods: The sample consisted of 21 schoolchildren, aged between 6 years and 11 months and 11 years, with mixed dentition, posterior reverse articulation (posterior cross bite, and erupted permanent first molars. The children were randomly divided into two groups: Group1 (composed of eleven children, in whom the encapsulated rapid maxilla expander was used, and Group 2 (composed of ten children, inwhom the conventional Hyrax expander was used. Three lateral teleradiographs of each individual were taken: before treatment, after rapid maxillary expansion, and after a containment period of five months. The cephalometric measurements used for analyzing the incisors were: /1.NB, /1-NB, /1-Line I, IMPA and /1-Jr. The data were submitted to the Dalhberg test, to calculate the error of repeatability, and to ANOVA (p<0.05. Results: The result showed significant difference between the adopted mechanics, but showed no difference between the initial measures, those after rapid expansion of the maxilla and final measures for all the distances, except for /1-Jr. Conclusion: Rapid maxillary expansion, using the encapsulated appliance or Hyrax, caused no significant alteration in the distances: /1.NB, /1-NB, /1-Line I, IMPA; before, after rapid maxillary expansion and after containment.

  10. Rapid adaptive evolution of photoperiodic response during invasion and range expansion across a climatic gradient.

    Science.gov (United States)

    Urbanski, Jennifer; Mogi, Motoyoshi; O'Donnell, Deborah; DeCotiis, Mark; Toma, Takako; Armbruster, Peter

    2012-04-01

    Abstract Understanding the mechanisms of adaptation to spatiotemporal environmental variation is a fundamental goal of evolutionary biology. This issue also has important implications for anticipating biological responses to contemporary climate warming and determining the processes by which invasive species are able to spread rapidly across broad geographic ranges. Here, we compare data from a historical study of latitudinal variation in photoperiodic response among Japanese and U.S. populations of the invasive Asian tiger mosquito Aedes albopictus with contemporary data obtained using comparable methods. Our results demonstrated rapid adaptive evolution of the photoperiodic response during invasion and range expansion across ∼15° of latitude in the United States. In contrast to the photoperiodic response, size-based morphological traits implicated in climatic adaptation in a wide range of other insects did not show evidence of adaptive variation in Ae. albopictus across either the U.S. (invasive) or Japanese (native) range. These results show that photoperiodism has been an important adaptation to climatic variation across the U.S. range of Ae. albopictus and, in conjunction with previous studies, strongly implicate the photoperiodic control of seasonal development as a critical evolutionary response to ongoing contemporary climate change. These results also emphasize that photoperiodism warrants increased attention in studies of the evolution of invasive species.

  11. Modified-casted Appliance for Surgically-assisted Rapid Palatal Expansion: A Clinical Report

    Directory of Open Access Journals (Sweden)

    Puneet Batra

    2014-01-01

    Full Text Available Transverse maxilla-mandibular discrepancies are a major component of several malocclusions. Surgically assisted rapid palatal expansion (SARPE is a common treatment modality for older patients in the correction of a maxillary transverse deficiency. In such cases, retention of the appliance plays an important role and this becomes a problem in patients having enamel hypoplasia. Therefore, the design was modified of a tooth-borne rapid maxillary expansion appliance with provision for miniscrew skeletal anchorage in a Class II malocclusion case having anterior open bite with bilateral posterior crossbite and enamel hypoplasia.

  12. Population genetic structure of a microalgal species under expansion.

    Directory of Open Access Journals (Sweden)

    Karen Lebret

    Full Text Available Biological invasions often cause major perturbations in the environment and are well studied among macroorganisms. Less is known about invasion by free-living microbes. Gonyostomum semen (Raphidophyceae is a freshwater phytoplankton species that has increased in abundance in Northern Europe since the 1980's and has expanded its habitat range. In this study, we aimed to determine the genetic population structure of G. semen in Northern Europe and to what extent it reflects the species' recent expansion. We sampled lakes from 12 locations (11 lakes in Norway, Sweden and Finland. Multiple strains from each location were genotyped using Amplified Fragment Length Polymorphism (AFLP. We found low differentiation between locations, and low gene diversity within each location. Moreover, there was an absence of genetic isolation with distance (Mantel test, p = 0.50. According to a Bayesian clustering method all the isolates belonged to the same genetic population. Together our data suggest the presence of one metapopulation and an overall low diversity, which is coherent with a recent expansion of G. semen.

  13. Population priorities: the challenge of continued rapid population growth.

    Science.gov (United States)

    Turner, Adair

    2009-10-27

    Rapid population growth continues in the least developed countries. The revisionist case that rapid population could be overcome by technology, that population density was advantageous, that capital shallowing is not a vital concern and that empirical investigations had not proved a correlation between high population growth and low per capita income was both empirically and theoretically flawed. In the modern world, population density does not play the role it did in nineteenth-century Europe and rates of growth in some of today's least developed nations are four times than those in nineteenth-century Europe, and without major accumulation of capital per capita, no major economy has or is likely to make the low- to middle-income transition. Though not sufficient, capital accumulation for growth is absolutely essential to economic growth. While there are good reasons for objecting to the enforced nature of the Chinese one-child policy, we should not underestimate the positive impact which that policy has almost certainly had and will have over the next several decades on Chinese economic performance. And a valid reticence about telling developing countries that they must contain fertility should not lead us to underestimate the severely adverse impact of high fertility rates on the economic performance and prospects of many countries in Africa and the Middle East.

  14. Clinical scale rapid expansion of lymphocytes for adoptive cell transfer therapy in the WAVE® bioreactor

    Science.gov (United States)

    2012-01-01

    Background To simplify clinical scale lymphocyte expansions, we investigated the use of the WAVE®, a closed system bioreactor that utilizes active perfusion to generate high cell numbers in minimal volumes. Methods We have developed an optimized rapid expansion protocol for the WAVE bioreactor that produces clinically relevant numbers of cells for our adoptive cell transfer clinical protocols. Results TIL and genetically modified PBL were rapidly expanded to clinically relevant scales in both static bags and the WAVE bioreactor. Both bioreactors produced comparable numbers of cells; however the cultures generated in the WAVE bioreactor had a higher percentage of CD4+ cells and had a less activated phenotype. Conclusions The WAVE bioreactor simplifies the process of rapidly expanding tumor reactive lymphocytes under GMP conditions, and provides an alternate approach to cell generation for ACT protocols. PMID:22475724

  15. Rapid poleward range expansion of tropical reef corals in response to rising sea surface temperatures

    Science.gov (United States)

    Yamano, Hiroya; Sugihara, Kaoru; Nomura, Keiichi

    2011-02-01

    Rising temperatures caused by climatic warming may cause poleward range shifts and/or expansions in species distribution. Tropical reef corals (hereafter corals) are some of the world's most important species, being not only primary producers, but also habitat-forming species, and thus fundamental ecosystem modification is expected according to changes in their distribution. Although most studies of climate change effects on corals have focused on temperature-induced coral bleaching in tropical areas, poleward range shifts and/or expansions may also occur in temperate areas. We show the first large-scale evidence of the poleward range expansion of modern corals, based on 80 years of national records from the temperate areas of Japan, where century-long measurements of in situ sea-surface temperatures have shown statistically significant rises. Four major coral species categories, including two key species for reef formation in tropical areas, showed poleward range expansions since the 1930s, whereas no species demonstrated southward range shrinkage or local extinction. The speed of these expansions reached up to 14 km/year, which is far greater than that for other species. Our results, in combination with recent findings suggesting range expansions of tropical coral-reef associated organisms, strongly suggest that rapid, fundamental modifications of temperate coastal ecosystems could be in progress.

  16. Skeletal alterations associated with the use of bonded rapid maxillary expansion appliance.

    Science.gov (United States)

    Rossi, Moara de; Rossi, Andiara de; Abrão, Jorge

    2011-01-01

    Bonded maxillary expansion appliances have been suggested to control increases in the vertical dimension of the face after rapid maxillary expansion (RME). However, there is still no consensus in the literature about its real skeletal effects. The purpose of this prospective study was to evaluate, longitudinally, the vertical and sagittal cephalometric alterations after RME performed with bonded maxillary expansion appliance. The sample consisted of 26 children, with a mean age of 8.7 years (range: 6.9-10.9 years), with posterior skeletal crossbite and indication for RME. After maxillary expansion, the bonded appliance was used as a fixed retention for 3.4 months, being replaced by a removable retention subsequently. The cephalometric study was performed onto lateral radiographs, taken before treatment was started, and again 6.3 months after removing the bonded appliance. Intra-group comparison was made using paired t test. The results showed that there were no significant sagittal skeletal changes at the end of treatment. There was a small vertical skeletal increase in five of the eleven evaluated cephalometric measures. The maxilla displaced downward, but it did not modify the facial growth patterns or the direction of the mandible growth. Under the specific conditions of this research, it may be concluded that RME with acrylic bonded maxillary expansion appliance did promote signifciant vertical or sagittal cephalometric alterations. The vertical changes found with the use of the bonded appliance were small and probably transitory, similar to those occurred with the use of banded expansion appliances.

  17. Plasmodium vivax populations revisited: mitochondrial genomes of temperate strains in Asia suggest ancient population expansion

    Directory of Open Access Journals (Sweden)

    Miao Miao

    2012-02-01

    Full Text Available Abstract Background Plasmodium vivax is the most widely distributed human malaria parasite outside of Africa, and its range extends well into the temperate zones. Previous studies provided evidence for vivax population differentiation, but temperate vivax parasites were not well represented in these analyses. Here we address this deficit by using complete mitochondrial (mt genome sequences to elucidate the broad genetic diversity and population structure of P. vivax from temperate regions in East and Southeast Asia. Results From the complete mtDNA sequences of 99 clinical samples collected in China, Myanmar and Korea, a total of 30 different haplotypes were identified from 26 polymorphic sites. Significant differentiation between different East and Southeast Asian parasite populations was observed except for the comparison between populations from Korea and southern China. Haplotype patterns and structure diversity analysis showed coexistence of two different groups in East Asia, which were genetically related to the Southeast Asian population and Myanmar population, respectively. The demographic history of P. vivax, examined using neutrality tests and mismatch distribution analyses, revealed population expansion events across the entire P. vivax range and the Myanmar population. Bayesian skyline analysis further supported the occurrence of ancient P. vivax population expansion. Conclusions This study provided further resolution of the population structure and evolution of P. vivax, especially in temperate/warm-temperate endemic areas of Asia. The results revealed divergence of the P. vivax populations in temperate regions of China and Korea from other populations. Multiple analyses confirmed ancient population expansion of this parasite. The extensive genetic diversity of the P. vivax populations is consistent with phenotypic plasticity of the parasites, which has implications for malaria control.

  18. Modified hyrax splint for rapid maxillary expansion in esthetically concerned patients

    Directory of Open Access Journals (Sweden)

    Sarabjeet Singh Sandhu

    2015-01-01

    Full Text Available The orthodontic treatment of Class III malocclusion with a maxillary deficiency is often treated with maxillary protraction either with or without maxillary expansion. The routine procedure for rapid maxillary expansion includes banding on first premolars/first deciduous molars and the permanent first molars. However in some patients who are esthetically very conscious, banding of the first premolar would not be a good esthetic option. So for such circumstances we have designed a modified hyrax splint, which does not need the first premolars to be banded.

  19. Koreksi gigitan terbalik posterior dan anterior dengan alat cekat rapid maxillary expansion dan elastik intermaksila

    Directory of Open Access Journals (Sweden)

    Retno Dewati

    2014-06-01

    Full Text Available Background: Children with anterior and posterior crossbite usually have a complaint in aesthetic and masticatory function. It could caused by bad habits and hereditary factors which made worse condition. Purpose: The purpose of this case report was to report the use of orthodontic appliance rapid maxillary expansion (RPE and intermaxillary elastic to correct posterior and anterior crossbite in teenage patient. Case: A fourteen years-old teenage female patient came to Dental Hospital Dentistry Universitas Airlangga with case of anterior posterior cross bite and unerupted permanent teeth. Case management: The case was treated using orthodontic fixed appliance rapid maxillary expansion (RPE and followed by intermaxillary elastics. The posterior cross bite treatment took 4 weeks used of orthodontic fixed appliance RPE, while, treatment of anterior cross bite which used intermaxillary elactic was done within three month to achieved normal occlusion. Conclusion: This case report showed that the orthodontic appliance rapid maxillary expansion (RPE and intermaxillary elastic could be used to correct posterior and anterior crossbite.Latar belakang: Anak dengan gigitan terbalik anterior dan posterior pada umumnya mempunyai keluhan dalam hal estetik dan fungsi pengunyahan. Kondisi gigitan terbalik biasanya disebabkan oleh adanya kebiasaan buruk dan faktor keturunan yang semakin memperparah keadaan tersebut. Tujuan: Laporan kasus ini melaporkan pemakaian alat cekat rapid maxillary expansion (RPE dan elastik intermaksila untuk mengkoreksi gigitan terbalik posterior dan anterior pada anak remaja. Kasus: Pasien remaja perempuan berusia 14 tahun datang ke Rumah Sakit Gigi dan Mulut Fakultas Kedokteran Gigi Universitas Airlangga Surabaya dengan kasus gigitan terbalik anterior posterior dan terdapat gigi permanen yang tidak tumbuh. Tatalaksana kasus: Perawatan yang dilakukan adalah koreksi gigitan terbalik dengan menggunakan alat ortodonsia cekat rapid maxillary

  20. Three-Dimensional Force Measurements During Rapid Palatal Expansion in Sus scrofa

    Directory of Open Access Journals (Sweden)

    Kelly Goeckner

    2016-04-01

    Full Text Available Rapid palatal expansion is an orthodontic procedure widely used to correct the maxillary arch. However, its outcome is significantly influenced by factors that show a high degree of variability amongst patients. The traditional treatment methodology is based on an intuitive and heuristic treatment approach because the forces applied in the three dimensions are indeterminate. To enable optimal and individualized treatment, it is essential to measure the three-dimensional (3D forces and displacements created by the expander. This paper proposes a method for performing these 3D measurements using a single embedded strain sensor, combining experimental measurements of strain in the palatal expander with 3D finite element analysis (FEA. The method is demonstrated using the maxillary jaw from a freshly euthanized pig (Sus scrofa and a hyrax-design rapid palatal expander (RPE appliance with integrated strain gage. The strain gage measurements are recorded using a computer interface, following which the expansion forces and extent of expansion are estimated by FEA. A total activation of 2.0 mm results in peak total force of about 100 N—almost entirely along the direction of expansion. The results also indicate that more than 85% of the input activation is immediately transferred to the palate and/or teeth. These studies demonstrate a method for assessing and individualizing expansion magnitudes and forces during orthopedic expansion of the maxilla. This provides the basis for further development of smart orthodontic appliances that provide real-time readouts of forces and movements, which will allow personalized, optimal treatment.

  1. Effect of a low-level laser on bone regeneration after rapid maxillary expansion.

    Science.gov (United States)

    Cepera, Fernanda; Torres, Fernando C; Scanavini, Marco A; Paranhos, Luiz R; Capelozza Filho, Leopoldino; Cardoso, Mauricio A; Siqueira, Danieli C R; Siqueira, Danilo F

    2012-04-01

    In this study, we evaluated the effects of a low-level laser on bone regeneration in rapid maxillary expansion procedures. Twenty-seven children, aged 8 to 12 years, took part in the experiment, with a mean age of 10.2 years, divided into 2 groups: the laser group (n = 14), in which rapid maxillary expansion was performed in conjunction with laser use, and the no-laser group (n = 13), with rapid maxillary expansion only. The activation protocol of the expansion screw was 1 full turn on the first day and a half turn daily until achieving overcorrection. The laser type used was a laser diode (TWIN Laser; MMOptics, São Carlos, Brazil), according to the following protocol: 780 nm wavelength, 40 mW power, and 10 J/cm(2) density at 10 points located around the midpalatal suture. The application stages were 1 (days 1-5 of activation), 2 (at screw locking, on 3 consecutive days), 3, 4, and 5 (7, 14, and 21 days after stage 2). Occlusal radiographs of the maxilla were taken with the aid of an aluminum scale ruler as a densitometry reference at different times: T1 (initial), T2 (day of locking), T3 (3-5 days after T2), T4 (30 days after T3), and T5 (60 days after T4). The radiographs were digitized and submitted to imaging software (Image Tool; UTHSCSA, San Antonio, Tex) to measure the optic density of the previously selected areas. To perform the statistical test, analysis of covariance was used, with the time for the evaluated stage as the covariable. In all tests, a significance level of 5% (P maxillary expansion, provided efficient opening of the midpalatal suture and influenced the bone regeneration process of the suture, accelerating healing. Copyright © 2012 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  2. Influence of Orthodontic Rapid Maxillary Expansion on Nocturnal Enuresis in Children

    OpenAIRE

    Lidia Hyla-Klekot; Marek Truszel; Andrzej Paradysz; Lidia Postek-Stefańska; Marcin Życzkowski

    2015-01-01

    Background. The etiology of nocturnal enuresis (NE) is multifactorial and has not been fully explained yet. New ways of treatment are constantly being investigated, including the rapid maxillary expansion (RME). Methods. A total of 41 patients diagnosed with NE were divided into two experimental groups: A and B. Group A included 16 children who have been treated with RME. Group B comprised 25 children who have not undertaken orthodontic treatment. Children from both groups have been monitored...

  3. Changes of pulp-chamber dimensions 1 year after rapid maxillary expansion.

    Science.gov (United States)

    Baratieri, Carolina; Alves, Matheus; Mattos, Cláudia Trindade; Souza, Margareth Maria Gomes de; Ruellas, Antônio Carlos de Oliveira

    2013-04-01

    The purpose of this study was to examine the effect of orthopedic forces on maxillary first molars' and maxillary central incisors' pulp chambers in children having rapid maxillary expansion as the only intervention compared with children having no orthodontic intervention by using cone-beam computed tomography images. In this prospective controlled clinical study, we evaluated 60 maxillary first molars and 60 maxillary central incisors from 30 children (18 boys, 12 girls) in the mixed dentition and during the pubertal growth period. The treated group had rapid maxillary expansion with the Haas expander, followed by 6 months of retention and 6 months of follow-up out of retention; the control group had no intervention during the study. Cone-beam computed tomography scans were taken initially and 1 year after the rapid maxillary expansion active phase. Initially, a 3-dimensional scrolling in all pulp chambers of the evaluated teeth was performed with Dolphin Imaging software (version 11.0; Dolphin Imaging & Management Solutions, Chatsworth, Calif) to describe the incidence of pulp-chamber calcifications. The dimensions of the pulp chambers of the molars and incisors were also investigated. Cross-sectional and longitudinal slices were used for each molar (coronal and axial slices) and incisor (sagittal and axial slices). The area (mm(2)) was obtained from 3 slices of each kind (6 measurements for each tooth). The results suggest that rapid maxillary expansion did not induce new pulp-chamber calcification. Also, it did not interfere in normal pulp-chamber dimension changes of the anchorage molars. The pulp chamber of the central incisors can be expected to be minimally wider 1 year after the therapy. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  4. Changes in nasal air flow and school grades after rapid maxillary expansion in oral breathing children

    OpenAIRE

    Torre, Hilda; Alarcón, Jose Antonio

    2012-01-01

    Objective: To analyse the changes in nasal air flow and school grades after rapid maxillary expansion (RME) in oral breathing children with maxillary constriction. Material and Methods: Forty-four oral breathing children (mean age 10.57 y) underwent orthodontic RME with a Hyrax screw. Forty-four age-matched children (mean age 10.64 y) with nasal physiological breathing and adequate transverse maxillary dimensions served as the control group. The maxillary widths, nasal air flow assessed via p...

  5. Dental and skeletal effects of combined headgear used alone or in association with rapid maxillary expansion.

    Science.gov (United States)

    Farret, Milton Meri Benitez; Lima, Eduardo Martinelli de; Farret, Marcel M; Araújo, Laura Lutz de

    2015-10-01

    The aim of this study was to assess the effects of combined headgear used alone or in association with rapid maxillary expansion, as the first step for Class II malocclusion treatment. The sample comprised 61 patients divided into three groups: Group 1, combined headgear (CH); Group 2, CH + rapid maxillary expansion (CH + RME); and Group 3, control (CG). In Group 1, patients were treated with combined headgear until Class I molar relationship was achieved. In Group 2, the protocol for headgear was the same; however, patients were previously subject to rapid maxillary expansion. Results showed distal displacement of maxillary molars for both experimental groups (p < 0.001), with distal tipping only in Group 1 (CH) (p < 0.001). There was restriction of forward maxillary growth in Group 2 (CH + RME) (p < 0.05) and clockwise rotation of the maxilla in Group 1 (CH) (p < 0.05). Based on the results, it is possible to suggest that treatment with both protocols was efficient; however, results were more significant for Group 2 (CH + RME) with less side effects.

  6. Dental and skeletal effects of combined headgear used alone or in association with rapid maxillary expansion

    Directory of Open Access Journals (Sweden)

    Milton Meri Benitez Farret

    2015-10-01

    Full Text Available Objective: The aim of this study was to assess the effects of combined headgear used alone or in association with rapid maxillary expansion, as the first step for Class II malocclusion treatment.Methods:The sample comprised 61 patients divided into three groups: Group 1, combined headgear (CH; Group 2, CH + rapid maxillary expansion (CH + RME; and Group 3, control (CG. In Group 1, patients were treated with combined headgear until Class I molar relationship was achieved. In Group 2, the protocol for headgear was the same; however, patients were previously subject to rapid maxillary expansion.Results:Results showed distal displacement of maxillary molars for both experimental groups (p < 0.001, with distal tipping only in Group 1 (CH (p < 0.001. There was restriction of forward maxillary growth in Group 2 (CH + RME (p < 0.05 and clockwise rotation of the maxilla in Group 1 (CH (p < 0.05.Conclusion: Based on the results, it is possible to suggest that treatment with both protocols was efficient; however, results were more significant for Group 2 (CH + RME with less side effects.

  7. Molar changes with cervical headgear alone or in combination with rapid maxillary expansion.

    Science.gov (United States)

    Marchiori Farret, Marcel; de Lima, Eduardo Martinelli S; Pereira Araújo, Vanessa; Deon Rizzatto, Susana Maria; Macedo de Menezes, Luciane; Lima Grossi, Marcio

    2008-09-01

    To test the hypothesis that there is no difference in the distal movement of the maxillary first permanent molars when cervical headgear is used alone or in combination with rapid maxillary expansion. The sample was composed of 36 subjects (aged 9 to 13 years), treated in the Faculty of Dentistry, Pontifícia Universidade Cat;aaolica, Rio Grande do Sul, Brazil. The individuals were in good health and in their pubertal growth period. All had Class II division 1 malocclusion. The patients were divided into two groups: group 1 (22 subjects), Class II, with a normal transverse maxilla treated with cervical traction headgear (HG) 400 g 12 h/d, and group 2 (14 subjects), Class II maxillary transverse deficiency treated with rapid maxillary expansion plus cervical traction headgear (RME + HG). An additional group 3 (17 subjects) served as a control group and included individuals with the same characteristics. All subjects had two lateral cephalograms: initial (T1) and progress (T2), taken 6 months later. Differences between T1 and T2 were compared with the Student's t-test, and three groups were compared by the analysis of variance and Tukey multiple comparison test. Results showed greater distal tipping and greater distal movement of the first permanent molars in group 1 (HG) than in group 2 (RME + HG), P .05). The hypothesis was rejected. Cervical traction headgear alone produced greater distal movement effects in maxillary first permanent molars when compared with rapid maxillary expansion associated with cervical headgear.

  8. Prediction of Class II improvement after rapid maxillary expansion in early mixed dentition

    Directory of Open Access Journals (Sweden)

    Alberto Caprioglio

    2017-04-01

    Full Text Available Abstract Background The aim of this study is to identify cephalometric pretreatment parameters for prediction of Class II improvement induced by rapid maxillary expansion. Methods Lateral cephalograms of 30 patients (mean age 8.3 ± 1.6 years old showing Class II molar relationship and undergone to rapid maxillary expansion on the upper deciduous molars were traced before treatment, and molar relation changes were evaluated on dental casts before and after treatment. Overall treatment time lasted 10.2 ± 2 months. Good responders (18 subjects, 10 females and 8 males showed improvement of at least 2.50 mm, and bad responders (12 subjects, 7 females and 5 males showed no improvement, improvement less than 2.50 mm, or worsening of molar relationship after treatment. Student’s t test was used to assess significance of differences between groups, and discriminant analysis allowed identification of predictive pretreatment variables. Results Articular angle, superior gonial angle, and mandibular dimensions (Co-Gn, S-Ar, Ar-Go, Go-Me showed significant differences in the comparison between groups. Mandibular length Co-Gn and superior gonial angle were selected as significant predictive variable for discrimination. Conclusions Patients with smaller mandibular length and more acute superior gonial angle are expected to have more chances to improve molar Class II after rapid maxillary expansion.

  9. A Rapid Compression Expansion Machine (RCEM) for studying chemical kinetics: Experimental principle and first applications

    CERN Document Server

    Werler, Marc; Maas, Ulrich

    2016-01-01

    A novel extension of a rapid compression machine (RCM), namely a Rapid Compression Expansion Machine (RCEM), is described and its use for studying chemical kinetics is demonstrated. Like conventional RCMs, the RCEM quickly compresses a fuel/air mixture by pushing a piston into a cylinder; the resulting high temperatures and pressures initiate chemical reactions. In addition, the machine can rapidly expand the compressed gas in a controlled way by pulling the piston outwards again. This freezes chemical activity after a pre-defined reaction duration, and therefore allows a convenient probe sampling and ex-situ gas analysis of stable species. The RCEM therefore is a promising instrument for studying chemical kinetics, including also partially reacted fuel/air mixtures. The setup of the RCEM, its experimental characteristics and its use for studying chemical reactions are outlined in detail. To allow comparisons of RCEM results with predictions of chemical reaction mechanisms, a simple numerical model of the RCE...

  10. Novel micronisation β-carotene using rapid expansion supercritical solution with co-solvent

    Science.gov (United States)

    Kien, Le Anh

    2017-09-01

    Rapid expansion of supercritical solution (RESS) is the most common approach of pharmaceutical pacticle forming methods using supercritical fluids. The RESS method is a technology producing a small solid product with a very narrow particle size distribution, organic solvent-free particles. This process is also simple and easy to control the operating parameters in comparision with other ways based on supercritical techniques. In this study, β-carotene, a strongly colored red-orange pigment abundant in plants and fruits, has been forming by RESS. In addition, the size and morphology effect of four different RESS parameters including co-solvent, extraction temperature, and extraction pressure and expansion nozzle temperature has surveyed. The particle size distribution has been determined by using laser diffraction experiment. SEM has conducted to analyze the surface structure, DSC and FTIR for thermal and chemical structure analysis.

  11. Micronization of phenylbutazone by rapid expansion of supercritical CO2 solution.

    Science.gov (United States)

    Moribe, Kunikazu; Tsutsumi, Shun-ichiro; Morishita, Shoko; Shinozaki, Hiroshi; Tozuka, Yuichi; Oguchi, Toshio; Yamamoto, Keiji

    2005-08-01

    Rapid expansion of supercritical solutions (RESS) technique was applied for the preparation of phenylbutazone fine particles. The operating temperature and pressure affected the yield of the drug fine particles, which was evaluated by dissolving the sprayed product of drug into ethanol. Effect of pre- and post-expansion conditions on the particle size distribution of phenylbutazone was investigated and the smallest sample (mean particle size: 1.59 microm) was obtained when the RESS method was operated at a pressure of 26 MPa combined with a temperature of 32 degrees C. Physicochemical properties of the fine particles were investigated by powder X-ray diffraction and differential scanning calorimetry. It was found that the phenylbutazone fine particles obtained were meta-stable beta form under the experimental conditions tested, suggesting polymorphic transformation during the RESS process.

  12. An assessment of the maxilla after rapid maxillary expansion using cone beam computed tomography in growing children.

    Science.gov (United States)

    Woller, Jessica L; Kim, Ki Beom; Behrents, Rolf G; Buschang, Peter H

    2014-01-01

    With the advent of cone beam computed tomography (CBCT), it is now possible to quantitatively evaluate the effects of rapid maxillary expansion (RME) on the entire maxillary complex in growing patients. The purpose of this study is to use three-dimensional images to evaluate the displacement that occurs at the circummaxillary sutures (frontonasal, zygomaticomaxillary, intermaxillary, midpalatal, and transpalatal sutures) following rapid maxillary expansion in growing children. The CBCT scans of 25 consecutively treated RME patients (10 male, 15 female) with mean age of 12.3±2.6 years, were examined before expansion and immediately following the last activation of the expansion appliance. Statistically significant (Pmaxillary first molars due to RME was also statistically significant. There was no statistically significant displacement of the transpalatal suture. Rapid maxillary expansion results in significant displacement of the bones of circummaxillary sutures in growing children.

  13. Asymmetric rapid maxillary expansion in true unilateral crossbite malocclusion: a prospective controlled clinical study.

    Science.gov (United States)

    Ileri, Zehra; Basciftci, Faruk Ayhan

    2015-03-01

    To investigate the short-term effects of the asymmetric rapid maxillary (ARME) appliance on the vertical, sagittal, and transverse planes in patients with true unilateral posterior crossbite. Subjects were divided into two groups. The treatment group was comprised of 21 patients with unilateral posterior crossbite (mean age  =  13.3 ± 2.1 years). Members of this group were treated with the ARME appliance. The control group was comprised of 17 patients with Angle Class I who were kept under observation (mean age  =  12.3 ± 0.8 years). Lateral and frontal cephalograms were taken before the expansion (T1), immediately after expansion (T2), and at postexpansion retention (T3) in the treatment group and at preobservation (T1) and postobservation (T2) in the control group. A total of 34 measurements were assessed on cephalograms. For statistical analysis, the Wilcoxon test and analysis of covariance were used. The ARME appliance produced significant increases in nasal, maxillary base, upper arch, and lower arch dimensions (P ARME appliance created asymmetric increments in the transversal dimensions of the nose, maxilla, and upper arch in the short term. Asymmetric expansion therapy for subjects with unilateral maxillary deficiency may provide satisfactory outcomes in adolescents, with the exception of mandibular arch expansion. The triangular pattern of expansion caused clockwise rotation of the mandible and the occlusal plane and produced significant alterations in the vertical facial dimensions, whereas it created no displacement in maxilla in the sagittal plane.

  14. Intracoastal shipping drives patterns of regional population expansion by an invasive marine invertebrate

    Science.gov (United States)

    Understanding the factors contributing to expansion of non-native populations is a critical step toward accurate risk assessment and effective management of biological invasions. Numerous studies have attempted to predict spread of invasive populations by assessing habitat suitab...

  15. Molar changes with cervical headgear alone or in combination with rapid maxillary expansion

    OpenAIRE

    Farret, Marcel Marchiori; Lima, Eduardo Martinelli Santayana de; Araújo, Vanessa Pereira de; Rizzatto, Susana Maria Deon; Menezes, Luciane Macedo de; Grossi, Márcio Lima

    2008-01-01

    Objective: To test the hypothesis that there is no difference in the distal movement of the maxillary first permanent molars when cervical headgear is used alone or in combination with rapid maxillary expansion. Materials and Methods: The sample was composed of 36 subjects (aged 9 to 13 years), treated in the Faculty of Dentistry, Pontifícia Universidade Católica, Rio Grande do Sul, Brazil. The individuals were in good health and in their pubertal growth period. All had Class II division 1 ma...

  16. An assessment of the maxilla after rapid maxillary expansion using cone beam computed tomography in growing children

    OpenAIRE

    Woller,Jessica L.; Ki Beom Kim; Behrents, Rolf G.; Buschang, Peter H.

    2014-01-01

    INTRODUCTION: With the advent of cone beam computed tomography (CBCT), it is now possible to quantitatively evaluate the effects of rapid maxillary expansion (RME) on the entire maxillary complex in growing patients. OBJECTIVE: The purpose of this study is to use three-dimensional images to evaluate the displacement that occurs at the circummaxillary sutures (frontonasal, zygomaticomaxillary, intermaxillary, midpalatal, and transpalatal sutures) following rapid maxillary expansion in gro...

  17. Comparison between rapid and mixed maxillary expansion through an assessment of arch changes on dental casts.

    Science.gov (United States)

    Grassia, Vincenzo; d'Apuzzo, Fabrizia; Jamilian, Abdolreza; Femiano, Felice; Favero, Lorenzo; Perillo, Letizia

    2015-01-01

    Aim of this retrospective observational study was to compare upper and lower dental changes in patients treated with Rapid Maxillary Expansion (RME) and Mixed Maxillary Expansion (MME), assessed by dental cast analysis. Treatment groups consisted of 42 patients: the RME group (n = 21) consisted of 13 female and 8 male subjects with the mean age of 8.8 years ± 1.37 at T0 and 9.6 years ± 1.45 at T1; the MME group (n = 21) consisted of 12 female and 9 male patients with a mean age of 8.9 years ± 2.34 at T0 and 10.5 years ± 2.08 at T1. The upper and lower arch analysis was performed on four dental bilateral landmarks, on upper and lower casts; also upper and lower arch depths were measured. The groups were compared using independent sample t-test to estimate dental changes in upper and lower arches. Before expansion treatment (T0), the groups were similar for all examined variables (p>0.05). In both RME and MME group, significant increments in all the variables for maxillary and mandibular arch widths were observed after treatment. No significant differences in maxillary and mandibular arch depths were observed at the end of treatment in both groups. An evaluation of the changes after RME and MME (T1) showed statistically significant differences in mandibular arch depth (plip bumper effects" observed in the MME protocol.

  18. Dental and skeletal changes following surgically assisted rapid maxillary anterior-posterior expansion.

    Science.gov (United States)

    Ho, Cheng-Ting; Lo, Lun-Jou; Liou, Eric J W; Huang, Chiung Shing

    2008-01-01

    Lengthening the maxillary dental arch as a treatment approach for patients with maxillary deficiency and dental crowding is seldom reported. The purpose of this study was to assess dental and skeletal changes in the maxilla in the correction of maxillary deficiency associated with a retruded maxillary arch using a surgically assisted rapid maxillary anterior-posterior expansion appliance. Predistraction and postraction lateral cephalometric and periapical radiographs and maxillary dental casts of six young adolescents (four boys, two girls, mean age 11 years, 2 months) were examined. These patients received a maxillary anterior segmental osteotomy and distraction osteogenesis with an anteroposteriorly oriented Hyrax expansion appliance based on the biological principles of bone distraction. The retruded dental arch and dental crowding were successfully corrected. Significant forward movement of the point anterior nasal spine, point A, central incisors and first premolars was noted. The maxillary dental arch depth increased an average of 4.2 mm while the arch width remained unchanged. In total, 11.5 mm of dental space was created in the maxillary arch which was sufficient to resolve dental crowding. New bone formation along the distraction site was observed three months after distraction. The use of maxillary anterior segmental osteotomy combined with a Hyrax expansion distraction appliance was effective in arch lengthening and creation of dental space. An overcorrection in this interdental distraction osteogenesis could be a good treatment option for children with maxillary deficiency combined with crowded maxillary dentition.

  19. Efficient 3D frequency response modeling with spectral accuracy by the rapid expansion method

    KAUST Repository

    Chu, Chunlei

    2012-07-01

    Frequency responses of seismic wave propagation can be obtained either by directly solving the frequency domain wave equations or by transforming the time domain wavefields using the Fourier transform. The former approach requires solving systems of linear equations, which becomes progressively difficult to tackle for larger scale models and for higher frequency components. On the contrary, the latter approach can be efficiently implemented using explicit time integration methods in conjunction with running summations as the computation progresses. Commonly used explicit time integration methods correspond to the truncated Taylor series approximations that can cause significant errors for large time steps. The rapid expansion method (REM) uses the Chebyshev expansion and offers an optimal solution to the second-order-in-time wave equations. When applying the Fourier transform to the time domain wavefield solution computed by the REM, we can derive a frequency response modeling formula that has the same form as the original time domain REM equation but with different summation coefficients. In particular, the summation coefficients for the frequency response modeling formula corresponds to the Fourier transform of those for the time domain modeling equation. As a result, we can directly compute frequency responses from the Chebyshev expansion polynomials rather than the time domain wavefield snapshots as do other time domain frequency response modeling methods. When combined with the pseudospectral method in space, this new frequency response modeling method can produce spectrally accurate results with high efficiency. © 2012 Society of Exploration Geophysicists.

  20. Rapid maxillary expansion outcomes in treatment of obstructive sleep apnea in children.

    Science.gov (United States)

    Villa, Maria Pia; Rizzoli, Alessandra; Rabasco, Jole; Vitelli, Ottavio; Pietropaoli, Nicoletta; Cecili, Manuela; Marino, Alessandra; Malagola, Caterina

    2015-06-01

    The objectives of this study were to confirm the efficacy of rapid maxillary expansion in children with moderate adenotonsillar hypertrophy in a larger sample and to evaluate retrospectively its long-term benefits in a group of children who underwent orthodontic treatment 10 years ago. After general clinical examination and overnight polysomnography, all eligible children underwent cephalometric evaluation and started 12 months of therapy with rapid maxillary expansion. A new polysomnography was performed at the end of treatment (T1). Fourteen children underwent clinical evaluation and Brouilette questionnaire, 10 years after the end of treatment (T2). Forty patients were eligible for recruitment. At T1, 34/40 (85%) patients showed a decrease of apnea-hypopnea index (AHI) greater than 20% (ΔAHI 67.45% ± 25.73%) and were defined responders. Only 6/40 (15%) showed a decrease  1 ev/h) after treatment. Disease duration was significantly lower (2.5 ± 1.4 years vs 4.8 ± 1.9 years, p children (mean age 17.0 ± 1.9 years) who ended orthodontic treatment 10 years previously showed improvement of Brouilette score. Starting an orthodontic treatment as early as symptoms appear is important in order to increase the efficacy of treatment. An integrated therapy is needed. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Rapid expansion method (REM) for time‐stepping in reverse time migration (RTM)

    KAUST Repository

    Pestana, Reynam C.

    2009-01-01

    We show that the wave equation solution using a conventional finite‐difference scheme, derived commonly by the Taylor series approach, can be derived directly from the rapid expansion method (REM). After some mathematical manipulation we consider an analytical approximation for the Bessel function where we assume that the time step is sufficiently small. From this derivation we find that if we consider only the first two Chebyshev polynomials terms in the rapid expansion method we can obtain the second order time finite‐difference scheme that is frequently used in more conventional finite‐difference implementations. We then show that if we use more terms from the REM we can obtain a more accurate time integration of the wave field. Consequently, we have demonstrated that the REM is more accurate than the usual finite‐difference schemes and it provides a wave equation solution which allows us to march in large time steps without numerical dispersion and is numerically stable. We illustrate the method with post and pre stack migration results.

  2. Cone-beam computed tomography evaluation of dentoskeletal changes after asymmetric rapid maxillary expansion.

    Science.gov (United States)

    Baka, Zeliha Muge; Akin, Mehmet; Ucar, Faruk Izzet; Ileri, Zehra

    2015-01-01

    The aims of this study were to quantitatively evaluate the changes in arch widths and buccolingual inclinations of the posterior teeth after asymmetric rapid maxillary expansion (ARME) and to compare the measurements between the crossbite and the noncrossbite sides with cone-beam computed tomography (CBCT). From our clinic archives, we selected the CBCT records of 30 patients with unilateral skeletal crossbite (13 boys, 14.2 ± 1.3 years old; 17 girls, 13.8 ± 1.3 years old) who underwent ARME treatment. A modified acrylic bonded rapid maxillary expansion appliance including an occlusal locking mechanism was used in all patients. CBCT records had been taken before ARME treatment and after a 3-month retention period. Fourteen angular and 80 linear measurements were taken for the maxilla and the mandible. Frontally clipped CBCT images were used for the evaluation. Paired sample and independent sample t tests were used for statistical comparisons. Comparisons of the before-treatment and after-retention measurements showed that the arch widths and buccolingual inclinations of the posterior teeth increased significantly on the crossbite side of the maxilla and on the noncrossbite side of the mandible (P ARME treatment, the crossbite side of the maxilla and the noncrossbite side of the mandible were more affected than were the opposite sides. Copyright © 2015. Published by Elsevier Inc.

  3. Slow versus rapid maxillary expansion in bilateral cleft lip and palate: a CBCT randomized clinical trial.

    Science.gov (United States)

    de Almeida, Araci Malagodi; Ozawa, Terumi Okada; Alves, Arthur César de Medeiros; Janson, Guilherme; Lauris, José Roberto Pereira; Ioshida, Marilia Sayako Yatabe; Garib, Daniela Gamba

    2017-06-01

    The purpose of this "two-arm parallel" trial was to compare the orthopedic, dental, and alveolar bone plate changes of slow (SME) and rapid (RME) maxillary expansions in patients with complete bilateral cleft lip and palate (BCLP). Forty-six patients with BCLP and maxillary arch constriction in the late mixed dentition were randomly and equally allocated into two groups. Computer-generated randomization was used. Allocation was concealed with sequentially, numbered, sealed, opaque envelopes. The SME and RME groups comprised patients treated with quad-helix and Haas/Hyrax-type expanders, respectively. Cone-beam computed tomography (CBCT) exams were performed before expansion and 4 to 6 months post-expansion. Nasal cavity width, maxillary width, alveolar crest width, arch width, palatal cleft width, inclination of posterior teeth, alveolar crest level, and buccal and lingual bone plate thickness were assessed. Blinding was applicable for outcome assessment only. Interphase and intergroup comparisons were performed using paired t tests and t tests, respectively (p Palatal cleft width had a significant increase in both groups. Significant buccal inclination of posterior teeth was only observed for RME. Additionally, both expansion procedures promoted a slight reduction of the alveolar crest level and the buccal bone plate thickness. No difference was found between the orthopedic, dental, and alveolar bone plate changes of SME and RME in children with BCLP. Both appliances produced significant skeletal transverse gains with negligible periodontal bone changes. Treatment time for SME, however, was longer than the observed for RME. SME and RME can be similarly indicated to correct maxillary arch constriction in patients with BCLP in the mixed dentition.

  4. Maxillary Expansion

    OpenAIRE

    Agarwal, Anirudh; Mathur, Rinku

    2010-01-01

    ABSTRACT Maxillary transverse discrepancy usually requires expansion of the palate by a combination of orthopedic and orthodontic tooth movements. Three expansion treatment modalities are used today: rapid maxillary expansion, slow maxillary expansion and surgically assisted maxillary expansion.This article aims to review the maxillary expansion by all the three modalities and a brief on commonly used appliances.

  5. Population growth and settlement expansion in the fringes of Addis ...

    African Journals Online (AJOL)

    This study focuses on estimating the rate of urban settlement expansion in the fringes of Addis Ababa, and on examining the causes for this and the impacts it has on the livelihoods of the farming households living there. For this purpose, aerial photographs covering the study area, GIS tools and GPS were used; ...

  6. Three-dimensional assessment of buccal alveolar bone after rapid and slow maxillary expansion: a clinical trial study.

    Science.gov (United States)

    Brunetto, Mauricio; Andriani, Juliana da Silva Pereira; Ribeiro, Gerson Luiz Ulema; Locks, Arno; Correa, Marcio; Correa, Letícia Ruhland

    2013-05-01

    The purposes of this study were to analyze and compare the immediate effects of rapid and slow maxillary expansion protocols, accomplished by Haas-type palatal expanders activated in different frequencies of activation on the positioning of the maxillary first permanent molars and on the buccal alveolar bones of these teeth with cone-beam computerized tomography. The sample consisted of 33 children (18 girls, 15 boys; mean age, 9 years) randomly distributed into 2 groups: rapid maxillary expansion (n = 17) and slow maxillary expansion (n = 16). Patients in the rapid maxillary expansion group received 2 turns of activation (0.4 mm) per day, and those in the slow maxillary expansion group received 2 turns of activation (0.4 mm) per week until 8 mm of expansion was achieved in both groups. Cone-beam computerized tomography images were taken before treatment and after stabilization of the jackscrews. Data were gathered through a standardized analysis of cone-beam computerized tomography images. Intragroup statistical analysis was accomplished with the Wilcoxon matched-pairs test, and intergroup statistical analysis was accomplished with analysis of variance. Linear relationships, among all variables, were determined by Spearman correlation. Both protocols caused buccal displacement of the maxillary first permanent molars, which had more bodily displacement in the slow maxillary expansion group, whereas more inclination was observed in the rapid maxillary expansion group. Vertical and horizontal bone losses were found in both groups; however, the slow maxillary expansion group had major bone loss. Periodontal modifications in both groups should be carefully considered because of the reduction of spatial resolution in the cone-beam computerized tomography examinations after stabilization of the jackscrews. Modifications in the frequency of activation of the palatal expander might influence the dental and periodontal effects of palatal expansion. Copyright © 2013

  7. Rapid Urban Expansion and Its Implications on Geomorphology: A Remote Sensing and GIS Based Study

    Directory of Open Access Journals (Sweden)

    S. N. Mohapatra

    2014-01-01

    Full Text Available Topography, vegetation, climate, water table, and even the anthropogenic activities all are affected by urban growth through diverse mechanisms. The present study focuses on the implications of urban expansion on geomorphology in the historical city of Gwalior in central India. The expansion of urban area has been quantified by deriving data for four decades (1972–2013 from the Landsat images. The results show that the urban built-up area has increased by 08.48 sq. km during the first eighteen years (1972–1990 which has increased to 16.28 sq. km during the next sixteen years (1990–2006. The built-up area has gone up to 23.19 sq. km in the next seven years (2006–2013. Overall during the last 40 years the growth of the urban built-up is nearly three times of the built-up areas in 1972. The average decadal growth rate of population is 27.28 percent while that of built-up land is 36.29 percent. The construction activities have affected important geomorphic features such pediplain, buried pediplain, residual hills, and denudational hills. It was concluded that, instead of shortsighted urban development, proper measures should be taken in accordance with scientific planning for the urban expansion of the city in the future.

  8. Rapid differentiation of sexual signals in invasive toads: call variation among populations

    Science.gov (United States)

    Yasumiba, Kiyomi; Duffy, Richard L.; Parsons, Scott A.; Alford, Ross A.; Schwarzkopf, Lin

    2016-01-01

    Advertisement calls tend to differ among populations, based on morphological and environmental factors, or simply geographic distance, in many taxa. Invasive cane toads (Rhinella marina) were introduced to Australia in 1935 and their distribution has expanded at increasing rates over time. Rapid evolution occurred in morphological and behavioural characters that accelerate dispersal, but the effects of rapid expansion on sexual signals have not been examined. We collected advertisement calls from four populations of different ages since invasion, and analysed the geographic differentiation of seven call parameters. Our comparisons indicate that the calls of R. marina differ among Australian populations. The signal variation was not simply clinal with respect to population age, climate, or morphological differentiation. We suggest that selection on signalling among populations has been idiosyncratic and may reflect local female preferences or adaptation to environmental factors that are not clinal such as energy availability. PMID:27328666

  9. Changes in head posture after rapid maxillary expansion in patients with nasopharyngeal obstruction

    Directory of Open Access Journals (Sweden)

    Kjurchieva-Chuchkova G

    2016-09-01

    Full Text Available Introduction: Nasopharyngeal obstruction is an important etiologic factor in the development of an extreme vertical growth facial pattern, and insufficient transversal growth of the maxilla. The treatment outcomes associated with rapid maxillary expansion in the literature are mainly discussed in terms of changes in dentofacial morphology, without special reference to changes in the pharyngeal airway, the position of the mandible, hyoid bone and the tongue. Aim: The aim of this study was to evaluate the effects of rapid maxillary expansion (RME, on changes in head posture and airway dimension. Materials and methods: The cephalometric evaluation was conducted on thirty lateral cephalograms of patients with nasopharyngeal obstruction (mean age 9.11 years; standard deviation (SD ± 2.0; range 8-14 years treated with appliance for rapid maxillary expansion. Patients were randomly divided into two groups: 1 study group comprised of 15 patients treated with RME immediately after the first visit; 2 a control group comprised of 15 subjects monitored for approximately 12 months prior to commencing therapy, who became untreated controls. Lateral cephalograms, taken in the natural head position, were obtained at the first visit and 6 months later for all subjects. Six angular measurements were measured to describe craniocervical angulation, and five linear measurements were measured to describe airway dimension. Results: The investigated group treated with RME shows a statistically significant decrease in craniocervical angulation, especially at the angle of interaction between palatal plane and the tangent odontoid processus (4.07 degrees, for PP/OPT angle and angle interaction between palatal plane and the tangent of cervical vertebra (4.95 degrees for PP/CVT angle. Airway dimension in the treated group increased, especially at the levels PNS-ad1 (2.52 mm, ve-pve (2.97 mm, and uv-puv (2.88 mm. No significant changes were observed in the control group

  10. Investigation of Oral Candida Albicans Colonization in Patients Treated with Rapid Maxillary Expansion

    Directory of Open Access Journals (Sweden)

    Fundagül Bilgiç

    2017-11-01

    Full Text Available Objective: The purpose of this study was to investigate Candida albicans colonies in the oral microflora of patients treated with rapid maxillary expansion (RME. Materials and Methods: Totally 54 male and female subjects, including 27 using bonded rapid maxillary expander and 27 patients without orthodontic treatment, were entered in the present study. The study group consisted of 27 patients (14 females and 13 males suffering from both maxillary constriction and posterior cross-bite. Patients treated with a rigid acrylic, bonded rapid maxillary expander were evaluated two times using oral rinses: one at baseline (T0 and 2 after palatal spreading out (T1. The data were analyzed using a chi-square test and a Fisher’s exact test. Results: After the use of RME, no significant changes were found between the data showing C. albicans colonies at T0 and at T1 (p=1.964. Conclusion: Our data suggest that the RME therapy and appliance did not cause a significant change in oral C. albicans colonization.

  11. Volumetric upper airway changes after rapid maxillary expansion: a systematic review and meta-analysis.

    Science.gov (United States)

    Buck, Lloyd M; Dalci, Oyku; Darendeliler, M Ali; Papageorgiou, Spyridon N; Papadopoulou, Alexandra K

    2017-10-01

    Although Rapid Maxillary Expansion (RME) has been used for over a century, its effect on upper airways has not yet adequately been assessed in an evidence-based manner. To investigate the volumetric changes in the upper airway spaces following RME in growing subjects by means of acoustic rhinometry, three-dimensional radiography and digital photogrammetry. Literature search of electronic databases and additional manual searches up to February 2016. Randomized clinical trials, prospective or retrospective controlled clinical trials and cohort clinical studies of at least eight patients, where the RME appliance was left in place for retention, and a maximum follow-up of 8 months post-expansion. After duplicate data extraction and assessment of the risk of bias, the mean differences and 95 per cent confidence intervals (CIs) of upper airway volume changes were calculated with random-effects meta-analyses, followed by subgroup analyses, meta-regressions, and sensitivity analyses. Twenty studies were eligible for qualitative synthesis, of which 17 (3 controlled clinical studies and 14 cohort studies) were used in quantitative analysis. As far as total airway volume is concerned patients treated with RME showed a significant increase post-expansion (5 studies; increase from baseline: 1218.3mm3; 95 per cent CI: 702.0 to 1734.6mm3), which did not seem to considerably diminish after the retention period (11 studies; increase from baseline: 1143.9mm3; 95 per cent CI: 696.9 to 1590.9mm3). However, the overall quality of evidence was judged as very low, due to methodological limitations of the included studies, absence of untreated control groups, and inconsistency among studies. RME seems to be associated with an increase in the nasal cavity volume in the short and in the long term. However, additional well-conducted prospective controlled clinical studies are needed to confirm the present findings. None. Australian Society of Orthodontics Foundation for Research and

  12. Rapid maxillary expansion in the primary and mixed dentitions: a cephalometric evaluation.

    Science.gov (United States)

    da Silva Filho, O G; Boas, M C; Capelozza Filho, L

    1991-08-01

    The present study evaluated the skeletal alterations induced by rapid maxillary expansion procedures in 30 patients in the primary and mixed dentitions. The results were obtained with the use of lateral cephalometrics before and immediately after the active phase of expansion. The time span between these two cephalometric films ranged from 14 to 21 days; therefore the "growth factor" was not considered. Based on the differences in the cephalometric measurements studied on the first and second tracings, it seems that anterior displacement of the maxilla with significant changes in the SNA angle should not be expected, although point B was repositioned more posteriorly (SNB) because of the mandibular downward and backward rotation, with subsequent increase of the inclination of the mandibular plane. The alterations in the A-P position of the mandible was reflected in the increase of ANB and NAP angles. The maxilla always dislocates downward, displaying a downward and backward rotation in the palatine plane, significantly altering the following measurements: N-ANS, PNS-PNS', A-A', SN.PP. The anchoring molars also follow the downward maxillary displacement (M-M') and, as a direct consequence of the vertical displacement of the maxilla and upper molars (N-ANS, A-A', ANS-Me, N-Me, PNS-PNS'), the facial heights increase.

  13. Miniscrew-assisted rapid palatal expansion for managing arch perimeter in an adult patient

    Directory of Open Access Journals (Sweden)

    Amanda Carneiro da Cunha

    Full Text Available ABSTRACT Introduction: Etiology of dental crowding may be related to arch constriction in diverse dimensions, and an appropriate manipulation of arch perimeter by intervening in basal bone discrepancies cases, may be a key for crowding relief, especially when incisors movement is limited due to underlying pathology, periodontal issues or restrictions related to soft tissue profile. Objectives: This case report illustrates a 24-year old woman, with maxillary transverse deficiency, upper and lower arches crowding, Class II, division 1, subdivision right relationship, previous upper incisors traumatic episode and straight profile. A non-surgical and non-extraction treatment approach was feasible due to the miniscrew-assisted rapid palatal expansion technique (MARPE. Methods: The MARPE appliance consisted of a conventional Hyrax expander supported by four orthodontic miniscrews. A slow expansion protocol was adopted, with an overall of 40 days of activation and a 3-month retention period. Intrusive traction miniscrew-anchored mechanics were used for correcting the Class II subdivision relationship, managing lower arch perimeter and midline deviation before including the upper central incisors. Results: Post-treatment records show an intermolar width increase of 5 mm, bilateral Class I molar and canine relationships, upper and lower crowding resolution, coincident dental midlines and proper intercuspation. Conclusions: The MARPE is an effective treatment approach for managing arch-perimeter deficiencies related to maxillary transverse discrepancies in adult patients.

  14. Bone density of the midpalatal suture 7 months after surgically assisted rapid palatal expansion in adults.

    Science.gov (United States)

    Petrick, Silvia; Hothan, Thorsten; Hietschold, Volker; Schneider, Matthias; Harzer, Winfried; Tausche, Eve

    2011-04-01

    The aims of this study were to analyze changes in bone density of the midpalatal suture after surgically assisted rapid palatal expansion (SARPE) with the bone-borne Dresden Distractor (DD; ITU, Dresden, Germany) via computed tomography (CT) and to compare of preoperative surgical findings with a control group. Sixteen adult patients (mean age 24.5 years) underwent axial CT scans before and 7 months after SARPE. CT image fusion was performed for the midpalatal suture bone. Sixty-six controls (mean age 25.7 years) served for comparing age-related bone density. Bone structure and density were assessed in the coronal plane at the anterior, median, and posterior levels. Highest density was found in the posterior part (1046 Hounsfield units [HU]) before expansion. Seven months after SARPE, bone density was 48% (anterior), 53% (median), and 75% (posterior) compared with preoperative values. The control group showed fairly equal Hounsfield units (889 HU to 900 HU) in all parts. Seven months after SARPE, the midpalatal suture's density achieves just one half to three quarters of the pretreatment values. To maintain the resistance against forces from the unsplit posterior part, the retention time should be lengthened. Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  15. Rapid maxillary expansion in therapy-resistant enuretic children: An orthodontic perspective.

    Science.gov (United States)

    Bazargani, Farhan; Jönson-Ring, Ingrid; Nevéus, Tryggve

    2016-05-01

    To evaluate whether rapid maxillary expansion (RME) could reduce the frequency of nocturnal enuresis (NE) in children and whether a placebo effect could be ruled out. Thirty-four subjects, 29 boys and five girls with mean age of 10.7 ± 1.8 years suffering from primary NE, were recruited. All subjects were nonresponders to the first-line antienuretic treatment and therefore were classified as "therapy resistant." To rule out a placebo effect of the RME appliance, all children were first treated with a passive appliance for 4 weeks. Rhinomanometry (RM), acoustic rhinometry (AR), polysomnographic registration, and study casts were made at different time points. One child experienced severe discomfort from the RME appliance and immediately withdrew from the study. Following RME, the long-term cure rate after 1 year was 60%. The RM and AR measurements at baseline and directly after RME showed a significant increase in nasal volume and nasal airflow, and there was a statistically significant correlation between reduction in enuresis and increase in nasal volume. Six months postretention, a 100% relapse of the dental overexpansion could be noted. RME has a curative effect in some children with NE, which could be connected to the positive influence of RME on the sleep architecture. Normal transverse occlusion does not seem to be a contraindication for moderate maxillary expansion in attempts to cure NE in children.

  16. Periodontal and dental effects of surgically assisted rapid maxillary expansion, assessed by using digital study models

    Directory of Open Access Journals (Sweden)

    Danilo Furquim Siqueira

    2015-06-01

    Full Text Available OBJECTIVE: The present study assessed the maxillary dental arch changes produced by surgically assisted rapid maxillary expansion (SARME. METHODS: Dental casts from 18 patients (mean age of 23.3 years were obtained at treatment onset (T1, three months after SARME (T2 and 6 months after expansion (T3. The casts were scanned in a 3D scanner (D-250, 3Shape, Copenhagen, Denmark. Maxillary dental arch width, dental crown tipping and height were measured and assessed by ANOVA and Tukey's test. RESULTS: Increased transversal widths from T1 and T2 and the maintenance of these values from T2 and T3 were observed. Buccal teeth tipping also showed statistically significant differences, with an increase in all teeth from T1 to T2 and a decrease from T2 to T3. No statistically significant difference was found for dental crown height, except for left first and second molars, although clinically irrelevant. CONCLUSION: SARME proved to be an effective and stable procedure, with minimum periodontal hazards.

  17. A Case of Re-Expansion Pulmonary Edema after Rapid Pleural Evacuation

    Directory of Open Access Journals (Sweden)

    SH Shahbazi

    2007-07-01

    Full Text Available Introduction & Objective: Pulmonary edema after chest tube insertion is a rare complication and is associated with high mortality. The cause of this phenomenon is not clear, although causes such as decrease in surfactant and inflammatory process have been defined. Early diagnosis and treatment decrease the mortality. This study introduces a case of re-expansion pulmonary edema after rapid pleural evacuation. Case: The case is a 4.5 y/o boy, a case of Tetralogy of Fallot, who developed respiratory distress after surgery (Total Correction in ICU of Namazi Hospital in 1385. Chest X ray showed pneumothorax of left lung. For the patient, chest tube was inserted and the symptoms improved. After few hours the patient developed tachypnea, tachycardia, and CXR showed pulmonary edema of left lung. Appropriate treatment was done for the patient and his condition improved. Conclusion: Pulmonary edema after sudden evacuation of pleura is a rare phenomenon and early diagnosis decreases the mortality.

  18. Rapid maxillary expansion and obstructive sleep apnea: A review and meta-analysis.

    Science.gov (United States)

    Machado-Júnior, A-J; Zancanella, E; Crespo, A-N

    2016-07-01

    OSAS during childhood leads to significant physical and neuropsychomotor impairment. Thus, it needs to be recognized and treated early in order to avoid or attenuate the chronic problems associated with OSAS, which are deleterious to a child's development. Adenotonsillectomy and, in select cases, continuous positive airwaypressure (CPAP) have been the preferred treatments for OSAS in children, and yet they are ineffective at fully ameliorating the disease. Minimally invasive treatments have recently been proposed, comprising intra-oral and extra-oral devices as well as speech therapy. Objetive: to conduct a meta-analysis on studies from around the world that used rapid maxillary expansion (RME) to treat OSAS in children. We performed a meta-analysis of studies using RME for OSA treatment in children. A literature survey was conductedusing PubMed and Medline for English articles published up to December 2014 with the following descriptors: SleepApnea, Obstructive, Children, Treatment, Orthodontic, Othopaedic, Maxillaryexpansion. Studies were included in the meta-analysisif they were case-controlled studies, randomized, and involved non-syndromic children aged 0 to 12years old diagnosed with OSA by the polysomnography apnea-hypopnea index (AHI) before and after the intervention, submitted RME only. In all, 10 articles conformed to the inclusion criteria and were included in this meta-analysis. The total sample size across all these articles was 215 children, having a mean age of 6.7 years,of whom58.6%were male. The mean AHI during the follow-up was -6.86 (p <0.0001). We concluded that rapid maxillary expansion (RME) in children with OSAS appears to be an effective treatment for this syndrome. Further randomized clinical studies are needed to determine the effectiveness of RME in adults.

  19. Determination of forces on a split palatal screw after rapid maxillary expansion.

    Science.gov (United States)

    García, Valentin Javier; López-Cancelos, Rubén; Riveiro, Antonio; Comesaña, Rafael; Ustrell I Torrent, Josep Maria; Kasem, Khaled; Badaoui, Aida; Manzanares-Céspedes, Mª Cristina; Carvalho-Lobato, Patricia

    2017-09-01

    Aim of this study was to develop a finite element model of the forces that patients with rapid maxillary expansion bear and to validate it by a mechanical test. Computer-aided design models of the metallic screw and polymeric splint were modelled and discretized. Two forces were generated and considered independently: F1 at the temporary molar (2.5 N) and F2 at the permanent molar (2.5 N). The results of the finite element analysis were used to define the strain values which the anterior and posterior arms of the rapid maxillary expansion appliance bore as a linear function of F1-F2 by calculating the strain-force coefficient δ ij . Two strain gauge rosettes were attached to an appliance which was placed in an XY motorized stage to reproduce the same forces used in the finite element analysis. Once the system was validated, the matrix was inverted to determine forces F1 and F2 that a group of 40 patients underwent (median age 8.33 years, standard deviation 1.86 years) for 75 days, using their strain values. The parents of the patients activated a quarter turn (0.20 mm) twice a day until 50% transversal overcorrection was achieved. Finite element analysis showed that the effects of the forces on stress at the location of the arms were notably different. There was a satisfactory correlation between finite element analysis predictions and in vitro values. Dissipation of F1 and F2 in patients was predicted to be 62.5 and 80%, respectively, after 75 days of retention. These results back the finite element analysis model for force prediction.

  20. Range expansions transition from pulled to pushed waves with increasing cooperativity in an experimental microbial population

    Science.gov (United States)

    Gandhi, Saurabh; Yurtsev, Eugene; Korolev, Kirill; Gore, Jeff

    Range expansions are becoming more frequent due to environmental changes and rare long distance dispersal, often facilitated by anthropogenic activities. Simple models in theoretical ecology explain many emergent properties of range expansions, such as a constant expansion velocity, in terms of organism-level properties such as growth and dispersal rates. Testing these quantitative predictions in natural populations is difficult because of large environmental variability. Here, we used a controlled microbial model system to study range expansions of populations with and without intra-specific cooperativity. For non-cooperative growth, the expansion dynamics were dominated by population growth at the low-density front, which pulled the expansion forward. We found these expansions to be in close quantitative agreement with the classical theory of pulled waves by Fisher and Skellam, suitably adapted to our experimental system. However, as cooperativity increased, the expansions transitioned to being pushed, i.e. controlled by growth in the bulk as well as in the front. Although both pulled and pushed waves expand at a constant velocity and appear otherwise similar, their distinct dynamics leads to very different evolutionary consequences. Given the prevalence of cooperative growth in nature, understanding the effects of cooperativity is essential to managing invading species and understanding their evolution.

  1. Is There Any Evidence for Rapid, Genetically-Based, Climatic Niche Expansion in the Invasive Common Ragweed?

    Directory of Open Access Journals (Sweden)

    Laure Gallien

    Full Text Available Climatic niche shifts have been documented in a number of invasive species by comparing the native and adventive climatic ranges in which they occur. However, these shifts likely represent changes in the realized climatic niches of invasive species, and may not necessarily be driven by genetic changes in climatic affinities. Until now the role of rapid niche evolution in the spread of invasive species remains a challenging issue with conflicting results. Here, we document a likely genetically-based climatic niche expansion of an annual plant invader, the common ragweed (Ambrosia artemisiifolia L., a highly allergenic invasive species causing substantial public health issues. To do so, we looked for recent evolutionary change at the upward migration front of its adventive range in the French Alps. Based on species climatic niche models estimated at both global and regional scales we stratified our sampling design to adequately capture the species niche, and localized populations suspected of niche expansion. Using a combination of species niche modeling, landscape genetics models and common garden measurements, we then related the species genetic structure and its phenotypic architecture across the climatic niche. Our results strongly suggest that the common ragweed is rapidly adapting to local climatic conditions at its invasion front and that it currently expands its niche toward colder and formerly unsuitable climates in the French Alps (i.e. in sites where niche models would not predict its occurrence. Such results, showing that species climatic niches can evolve on very short time scales, have important implications for predictive models of biological invasions that do not account for evolutionary processes.

  2. Is There Any Evidence for Rapid, Genetically-Based, Climatic Niche Expansion in the Invasive Common Ragweed?

    Science.gov (United States)

    Gallien, Laure; Thuiller, Wilfried; Fort, Noémie; Boleda, Marti; Alberto, Florian J; Rioux, Delphine; Lainé, Juliette; Lavergne, Sébastien

    2016-01-01

    Climatic niche shifts have been documented in a number of invasive species by comparing the native and adventive climatic ranges in which they occur. However, these shifts likely represent changes in the realized climatic niches of invasive species, and may not necessarily be driven by genetic changes in climatic affinities. Until now the role of rapid niche evolution in the spread of invasive species remains a challenging issue with conflicting results. Here, we document a likely genetically-based climatic niche expansion of an annual plant invader, the common ragweed (Ambrosia artemisiifolia L.), a highly allergenic invasive species causing substantial public health issues. To do so, we looked for recent evolutionary change at the upward migration front of its adventive range in the French Alps. Based on species climatic niche models estimated at both global and regional scales we stratified our sampling design to adequately capture the species niche, and localized populations suspected of niche expansion. Using a combination of species niche modeling, landscape genetics models and common garden measurements, we then related the species genetic structure and its phenotypic architecture across the climatic niche. Our results strongly suggest that the common ragweed is rapidly adapting to local climatic conditions at its invasion front and that it currently expands its niche toward colder and formerly unsuitable climates in the French Alps (i.e. in sites where niche models would not predict its occurrence). Such results, showing that species climatic niches can evolve on very short time scales, have important implications for predictive models of biological invasions that do not account for evolutionary processes.

  3. Mandibular response after rapid maxillary expansion in class II growing patients: a pilot randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Roberta Lione

    2017-11-01

    Full Text Available Abstract Background The aim of this pilot randomized controlled trial (RCT was to evaluate the sagittal mandibular response induced by rapid maxillary expansion (RME therapy in mixed dentition patients with class II malocclusion, comparing the effects of bonded RME and banded RME with a matched untreated class II control group. Methods This RCT was designed in parallel with an allocation ratio of 1:1:1. The sample consisted of 30 children with a mean age of 8.1 ± 0.6 years who were randomly assigned to three groups: group 1 treated with bonded RME, group 2 treated with banded RME, and group 3 the untreated control group. All patients met the following inclusion criteria: early mixed dentition, class II molar relationship, transverse discrepancy ≥ 4 mm, overjet ≥ 5 mm, and prepubertal skeletal maturity stage (CS1–CS2. The expansion screw was activated one quarter of a turn per day (0.25 mm until overcorrection was reached. For each subject, lateral cephalograms and plaster casts were obtained before treatment (T1 and after 1 year (T2. A randomization list was created for the group assignment, with an allocation ratio of 1:1:1. The observer who performed all the measurements was blinded to group assignment. The study was single-blinded in regard to statistical analysis. Results RME was effective in the correction of maxillary deficiency. Class II patients treated with both types of RME showed no significant improvement of the anteroposterior relationship of the maxilla and the mandible at both skeletal and occlusal levels. The acrylic splint RME had significant effects on reducing the skeletal vertical dimension and the gonial angle. Conclusions The orthopedic expansion did not affect the sagittal relationship of class II patients treated in the early mixed dentition when compared with the untreated control group. Additional studies with a larger sample are warranted to elucidate individual variations in dento-skeletal mandibular

  4. Mandibular response after rapid maxillary expansion in class II growing patients: a pilot randomized controlled trial.

    Science.gov (United States)

    Lione, Roberta; Brunelli, Valerio; Franchi, Lorenzo; Pavoni, Chiara; Quiroga Souki, Bernardo; Cozza, Paola

    2017-11-06

    The aim of this pilot randomized controlled trial (RCT) was to evaluate the sagittal mandibular response induced by rapid maxillary expansion (RME) therapy in mixed dentition patients with class II malocclusion, comparing the effects of bonded RME and banded RME with a matched untreated class II control group. This RCT was designed in parallel with an allocation ratio of 1:1:1. The sample consisted of 30 children with a mean age of 8.1 ± 0.6 years who were randomly assigned to three groups: group 1 treated with bonded RME, group 2 treated with banded RME, and group 3 the untreated control group. All patients met the following inclusion criteria: early mixed dentition, class II molar relationship, transverse discrepancy ≥ 4 mm, overjet ≥ 5 mm, and prepubertal skeletal maturity stage (CS1-CS2). The expansion screw was activated one quarter of a turn per day (0.25 mm) until overcorrection was reached. For each subject, lateral cephalograms and plaster casts were obtained before treatment (T1) and after 1 year (T2). A randomization list was created for the group assignment, with an allocation ratio of 1:1:1. The observer who performed all the measurements was blinded to group assignment. The study was single-blinded in regard to statistical analysis. RME was effective in the correction of maxillary deficiency. Class II patients treated with both types of RME showed no significant improvement of the anteroposterior relationship of the maxilla and the mandible at both skeletal and occlusal levels. The acrylic splint RME had significant effects on reducing the skeletal vertical dimension and the gonial angle. The orthopedic expansion did not affect the sagittal relationship of class II patients treated in the early mixed dentition when compared with the untreated control group. Additional studies with a larger sample are warranted to elucidate individual variations in dento-skeletal mandibular response to the maxillary expansion protocol in class

  5. Three dimensional evaluation of alveolar bone changes in response to different rapid palatal expansion activation rates

    Directory of Open Access Journals (Sweden)

    Brian LaBlonde

    Full Text Available ABSTRACT Introduction: The aim of this multi-center retrospective study was to quantify the changes in alveolar bone height and thickness after using two different rapid palatal expansion (RPE activation protocols, and to determine whether a more rapid rate of expansion is likely to cause more adverse effects, such as alveolar tipping, dental tipping, fenestration and dehiscence of anchorage teeth. Methods: The sample consisted of pre- and post-expansion records from 40 subjects (age 8-15 years who underwent RPE using a 4-banded Hyrax appliance as part of their orthodontic treatment to correct posterior buccal crossbites. Subjects were divided into two groups according to their RPE activation rates (0.5 mm/day and 0.8 mm/day; n = 20 each group. Three-dimensional images for all included subjects were evaluated using Dolphin Imaging Software 11.7 Premium. Maxillary base width, buccal and palatal cortical bone thickness, alveolar bone height, and root angulation and length were measured. Significance of the changes in the measurements was evaluated using Wilcoxon signed-rank test and comparisons between groups were done using ANOVA. Significance was defined at p ≤ 0.05. Results: RPE activation rates of 0.5 mm per day (Group 1 and 0.8 mm per day (Group 2 caused significant increase in arch width following treatment; however, Group 2 showed greater increases compared to Group 1 (p < 0.01. Buccal alveolar height and width decreased significantly in both groups. Both treatment protocols resulted in significant increases in buccal-lingual angulation of teeth; however, Group 2 showed greater increases compared to Group 1 (p < 0.01. Conclusion: Both activation rates are associated with significant increase in intra-arch widths. However, 0.8 mm/day resulted in greater increases. The 0.8 mm/day activation rate also resulted in more increased dental tipping and decreased buccal alveolar bone thickness over 0.5 mm/day.

  6. Population structure and expansion of kuruma shrimp (Penaeus ...

    African Journals Online (AJOL)

    use

    Afr. J. Biotechnol. Palumbi SR, Baker Cs (1994). Contrasting population structure from nuclear intron sequences and mtDNA of humpback whales. Mol. Biol. Evol. 11:426-435. Rogers AR, Harpending H (1992). Population growth makes waves in the distribution of pairwise genetic differences. Mol. Biol. Evol. 9: 552-569.

  7. The rapid expansion of (mainstream) health psychology in France: Historical foundations.

    Science.gov (United States)

    Santiago-Delefosse, Marie; Del Rio Carral, Maria

    2017-06-01

    This article traces the historical evolution of ongoing theoretical debates in psychology in France from the 1940s until today. Its aim is to show how the conjunction of certain conditions was determinant for a rapid expansion of American-derived mainstream health psychology during the 1980s. The authors describe the French context in the post-World War II period that made possible the introduction of psychology courses at the university, which included the tensions between two epistemological orientations: experimental psychology and clinical psychology, the latter partly inspired by Politzer's concrete psychology. We also outline the process that led to the implementation of 'clinical psychology in health settings' in the 1950s, under the influence of Daniel Lagache. Furthermore, the strong critiques that were made to the new psychology profession in the 1950s, 1960s and 1970s are examined against oppositions among psychologists, psychiatrists, philosophers and psychoanalysts. Moreover, we discuss how under turbulent conditions, a pragmatic-oriented psychology arriving from the United States was smoothly and rapidly introduced in France during the 1980s, promoting a socio-cognitive framework and offering new career perspectives. But the French dissension to this new sub-discipline will also be considered. Finally, our conclusion reflects upon future implications of ongoing rivalries between different approaches to psychology. It underlines a growing interest in critical perspectives developed in Anglo-Saxon cultures which are being applied, by French academics and practitioners who work in psychology in health settings.

  8. Immediate impact of rapid maxillary expansion on upper airway dimensions and on the quality of life of mouth breathers

    Directory of Open Access Journals (Sweden)

    Edna Namiko Izuka

    2015-06-01

    Full Text Available OBJECTIVE: To assess short-term tomographic changes in the upper airway dimensions and quality of life of mouth breathers after rapid maxillary expansion (RME. METHODS: A total of 25 mouth breathers with maxillary atresia and a mean age of 10.5 years old were assessed by means of cone-beam computed tomography (CBCT and a standardized quality of life questionnaire answered by patients' parents/legal guardians before and immediately after rapid maxillary expansion. RESULTS: Rapid maxillary expansion resulted in similar and significant expansion in the width of anterior (2.8 mm, p < 0.001 and posterior nasal floor (2.8 mm, p < 0.001. Although nasopharynx and nasal cavities airway volumes significantly increased (+1646.1 mm3, p < 0.001, oropharynx volume increase was not statistically significant (+1450.6 mm3, p = 0.066. The results of the quality of life questionnaire indicated that soon after rapid maxillary expansion, patients' respiratory symptoms significantly decreased in relation to their initial respiratory conditions. CONCLUSIONS: It is suggested that RME produces significant dimensional increase in the nasal cavity and nasopharynx. Additionally, it also positively impacts the quality of life of mouth-breathing patients with maxillary atresia.

  9. Low larval densities in northern populations reinforce range expansion by a Mediterranean damselfly

    DEFF Research Database (Denmark)

    Therry, Lieven; Swaegers, Janne; Dinh, Khuong Van

    2016-01-01

    towards the very edge of the expansion front has been neglected. Density effects may, however, have a profound direct impact on traits involved in range expansion and influence range dynamics. 2. In this study, we contrast the effects of high conspecific larval density typical for established populations...... and low larval density typical for newly founded populations at the edge of the expansion front on a set of larval traits that may affect the range dynamics in the poleward moving damselfly Coenagrion scitulum. We therefore ran an outdoor mesocosm experiment with a low- and high-density treatment close...... in voltinism) at low conspecific density will translate in increased population growth rates. Furthermore, nutritional advantages at low conspecific density may increase investment in dispersal ability. Together, these direct and delayed density-dependent effects that gradually increase towards the expansion...

  10. Rapid maxillary expansion (RME) for pediatric obstructive sleep apnea: a 12-year follow-up.

    Science.gov (United States)

    Pirelli, Paola; Saponara, Maurizio; Guilleminault, Christian

    2015-08-01

    The objective of this study was to prospectively evaluate the long-term efficacy of rapid maxillary expansion (RME) in a group of children with obstructive sleep apnea (OSA). Thirty-one children diagnosed with OSA were involved in the study. These children had isolated maxillary narrowing and absence of enlarged adenotonsils at baseline. Twenty-three individuals (73% of the initial group) were followed up annually over a mean of 12 years after the completion of orthodontic treatment at a mean age of 8.68 years. Eight children dropped out over time due to either moving out of the area (n = 6) or refusal to submit to regular follow-up (n = 2). Subjects underwent clinical reevaluation over time and repeat polysomnography (PSG) in the late teenage years or in their early 20s. During the follow-up period, eight children dropped out and 23 individuals (including 10 girls) underwent a final clinical investigation with PSG (mean age of 20.9 years). The final evaluation also included computerized tomographic (CT) imaging that was compared with pre- and post-initial treatment findings. Yearly clinical evaluations, including orthodontic and otolaryngological examinations and questionnaire scores, were consistently normal over time, and PSG findings remained normal at the 12-year follow-up period. The stability and maintenance of the expansion over time was demonstrated by the maxillary base width and the distance of the pterygoid processes measured using CT imaging. A subgroup of OSA children with isolated maxillary narrowing initially and followed up into adulthood present stable, long-term results post RME treatment for pediatric OSA. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Analysis of the maxillary dental arch after rapid maxillary expansion in patients with unilateral complete cleft lip and palate.

    Science.gov (United States)

    Ayub, Priscila Vaz; Janson, Guilherme; Gribel, Bruno Frazão; Lara, Tulio Silva; Garib, Daniela Gamba

    2016-05-01

    Although rapid maxillary expansion has been extensively studied in noncleft patients, scarce evidence of maxillary effects is found for patients with oral clefts. Our objective was to evaluate the dentoalveolar effects of rapid maxillary expansion in children with unilateral complete cleft lip and palate compared with noncleft patients. The experimental group included 25 patients with unilateral complete cleft lip and palate and posterior crossbite (9 girls, 16 boys; mean age, 10.6 years). The control group comprised 27 noncleft patients with posterior crossbite (14 boys, 13 girls; mean age, 9.1 years). The experimental group had lip and palate repairs at 3 and 12 months of age, respectively, and maxillary expansion was indicated before a secondary alveolar bone graft. Digital dental models were obtained immediately before expansion and 6 months after expansion with a laser scanner. Canine and posterior tooth inclinations, transversal widths, arch perimeters, arch lengths, palatal depths, and palatal volumes were digitally measured. The paired t test was used for interphase comparisons, and the independent t test was used for intergroup comparisons (P expansion produced buccal tipping of the canines and posterior teeth and significant increases of all maxillary transverse measurements, arch perimeter, palatal volumes, and palatal depths; only arch lengths decreased. No differences were observed between the groups for any measurement, except for intermolar distance. Rapid maxillary expansion produced similar changes in the patients with unilateral complete cleft lip and palate compared with the noncleft patients except for arch length and palatal depth that decreased after expansion in the children with oral clefts. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  12. Deagglomeration and mixing via the rapid expansion of high pressure and supercritical suspensions

    Science.gov (United States)

    To, Daniel

    Nano-materials are the focus of many research activities due to the desirable properties imparted from their small grain size and high interfacial surface area. However, these materials are highly cohesive powders in the dry state and typically form large agglomerates, leading to a diminished surface area or even grain growth, which minimizes the effectiveness of these nanomaterials. This dissertation addresses the issue of mixing nanopowders constituents by deagglomerating them and achieving simultaneous mixing so that even after inevitable reagglomeration, the effectiveness of large interfacial surface area may be preserved. Nano-particle mixtures were prepared using the environmentally benign dry mixing methods of Stirring in Supercritical Fluids and the Rapid Expansion of High Pressure and Supercritical Suspensions (REHPS). Stirring in Supercritical Fluids was capable of producing course scale nano-particle mixtures that were comparable to mixtures produced with more traditional liquid solvents, without the necessity of filtration and caking issues that are typically associated with them. The REHPS process was capable of producing high-quality mixtures on the sub-micron scale, and was made far superior when the nano-powders were first pre-mixed by stirring to decrease inhomogeneity of the feed. It was also shown that in general, conditions that enhanced turbulent shear stress, and thereby deagglomeration, also enhanced mixing, however this effect could be obscured by inhomogeneities introduced by the feed mixtures. Previous authors have suggested that the primary deagglomeration mechanism is the explosive expansion of the carbon dioxide from within the agglomerate as it transitions from a high pressure to an ambient environment. In this study two other deagglomeration mechanisms were proposed, namely intense turbulent shear stress imparted by the fluid in the nozzle and impaction with the Mach disc near the exit of the nozzle. Explosive expansion was observed

  13. [The indigenous population. Demographic expansion of ethnic groups].

    Science.gov (United States)

    Valdes De Montano, L M

    1989-01-01

    Analysis of the vital statistics of the 450 Mexican municipios in which 70% or more of the population speak indigenous languages permits a rough analysis of the demographic behavior of 23 different ethnic groups. Statistics of government departments dealing with indigenous affairs and the various indigenous organizations created since the 1970s provide other estimates of the size of the indigenous population. The census indicated a population of 5,181,038 speakers of indigenous languages aged 5 or older in 1980. The public administration estimated the 1980 indigenous population at 10 million, and the indigenous organizations estimated 12 to 18 million in 1980 and 15 million in 1989. Census and vital statistics data indicate that each indigenous group has had unique patterns of mortality and fertility in the past 30 years. Mortality declined significantly in some groups, but fertility overall has not declined to the same extent. In 1970 and 1980 respectively for the sample as a whole, the average crude birth rates were 42.4 and 37.3/1000 and the average crude death rates were 13.8 and 8.2/1000. The average annual growth rate was estimated at 2.9% for both years. 1980 growth rates ranged from 3.5% for the Maya and Mixtec to a low of 0.5% for the Tzotzil.

  14. Population structure and expansion of kuruma shrimp ( Penaeus ...

    African Journals Online (AJOL)

    Neighbor-joining tree and network of all alleles showed no significant genealogical structure. Analyses of molecular variance and FST also revealed no significant genetic structure among five populations, but the FST value between ECS and ETS was significant. Fu's F statistics and analysis of mismatch distribution for ...

  15. Rapid population increase in an introduced muskox population, West Greenland

    Directory of Open Access Journals (Sweden)

    Carsten Riis Olesen

    1993-10-01

    Full Text Available In 1962 and 1965, 27 (13 and 14 muskox yearlings were translocated from East Greenland (71°N to the Angujaartorfiup Nunaa range in West Greenland (67°N. Angujaartorfiup Nunaa is a 6600 km2 icefree, continental area where caribou are indigenous. The climate is strictly continental with a minimum of precipitation but with abundant vegetation. Aerial surveys in 1990 documented that the muskox population has increased to 2600 heads despite quota-based harvesting since 1988. The annual quota was 200, 300 and 400 for 1988, 1989 and 1990, respectively. Distribution of muskoxen shows a significant preference for low altitude habitats southeast of Kangerlussuaq Airport and around Arnangarnup Qoorua (Paradise valley. Annual population increment averages 30% and the calf crop is around 24% of the population. Yearling recruitment in the population reveals that calf mortality during winter is very limited. About half of the 1-year-old females are served and they eventually give birth to their first calf when they turn 2 years old. With half of the 2-year-old females reproducing, the calf/cow ration ranges between 0.9 and 1.0.

  16. Rapid cycling genomic selection in a multiparental tropical maize population

    Science.gov (United States)

    Genomic selection (GS) increases genetic gain by reducing the length of the selection cycle, as has been exemplified in maize using rapid cycling recombination of biparental populations. However, no results of GS applied to maize multi-parental populations have been reported so far. This study is th...

  17. An assessment of the maxilla after rapid maxillary expansion using cone beam computed tomography in growing children

    Directory of Open Access Journals (Sweden)

    Jessica L. Woller

    2014-01-01

    Full Text Available INTRODUCTION: With the advent of cone beam computed tomography (CBCT, it is now possible to quantitatively evaluate the effects of rapid maxillary expansion (RME on the entire maxillary complex in growing patients. OBJECTIVE: The purpose of this study is to use three-dimensional images to evaluate the displacement that occurs at the circummaxillary sutures (frontonasal, zygomaticomaxillary, intermaxillary, midpalatal, and transpalatal sutures following rapid maxillary expansion in growing children. METHODS: The CBCT scans of 25 consecutively treated RME patients (10 male, 15 female with mean age of 12.3 ± 2.6 years, were examined before expansion and immediately following the last activation of the expansion appliance. RESULTS: Statistically significant (P < 0.05 amounts of separation were found for the displacement of the bones of the frontonasal suture, the intermaxillary suture, the zygomaticomaxillary sutures, and the midpalatal suture. The change in angulation of the maxillary first molars due to RME was also statistically significant. There was no statistically significant displacement of the transpalatal suture. CONCLUSIONS: Rapid maxillary expansion results in significant displacement of the bones of circummaxillary sutures in growing children.

  18. Model of oronasal rehabilitation in children with obstructive sleep apnea syndrome undergoing rapid maxillary expansion: Research review

    OpenAIRE

    Levrini, Luca; Lorusso, Paola; Caprioglio, Alberto; Magnani, Augusta; Diaféria, Giovana; Bittencourt, Lia; Bommarito, Silvana

    2014-01-01

    Rapid maxillary expansion (RME) is a widely used practice in orthodontics. Scientific evidence shows that RME can be helpful in modifying the breathing pattern in mouth-breathing patients. In order to promote the restoration of physiological breathing we have developed a rehabilitation program associated with RME in children. The aim of the study was a literature review and a model of orofacial rehabilitation in children with obstructive sleep apnea undergoing treatment with rapid maxillary e...

  19. The Expansion of National Educational Systems: Tests of a Population Ecology Model

    Science.gov (United States)

    Nielsen, Francois; Hannan, Michael T.

    1977-01-01

    This paper investigates the expansion of enrollments in national systems of education during the 1950-1970 period from the point of view of the population ecology of organizations. A simplified dynamic model of the growth of a population of educational organizations is estimated using various techniques for pooling time series of data. (Author/JM)

  20. Dental arch changes associated with rapid maxillary expansion: A retrospective model analysis study

    Directory of Open Access Journals (Sweden)

    Ivor M D′Souza

    2015-01-01

    Full Text Available Introduction: Transverse deficiency of the maxilla is a common clinical problem in orthodontics and dentofacial orthopedics. Transverse maxillary deficiency, isolated or associated with other dentofacial deformities, results in esthetic and functional impairment giving rise to several clinical manifestations such as asymmetrical facial growth, positional and functional mandibular deviations, altered dentofacial esthetics, adverse periodontal responses, unstable dental tipping, and other functional problems. Orthopedic maxillary expansion is the preferred treatment approach to increase the maxillary transverse dimension in young patients by splitting of the mid palatal suture. This orthopedic procedure has lately been subject of renewed interest in orthodontic treatment mechanics because of its potential for increasing arch perimeter to alleviate crowding in the maxillary arch without adversely affecting facial profile. Hence, the present investigation was conducted to establish a correlation between transverse expansion and changes in the arch perimeter, arch width and arch length. Methods: For this purpose, 10 subjects (five males, five females were selected who had been treated by rapid maxillary expansion (RME using hyrax rapid palatal expander followed by fixed mechanotherapy (PEA. Pretreatment (T1, postexpansion (T2, and posttreatment (T3 dental models were compared for dental changes brought about by RME treatment and its stability at the end of fixed mechanotherapy. After model measurements were made, the changes between T1-T2, T2-T3 and T1-T3 were determined for each patient. The mean difference between T1-T2, T2-T3 and T1-T3 were compared to assess the effects of RME on dental arch measurements. Results are expressed as mean ± standard deviation and are compared by repeated measures analysis of variance followed by a post-hoc test. Arch perimeter changes are correlated with changes in arch widths at the canine, premolar and molar

  1. Rapid maxillary expansion for the treatment of nasal obstruction in children younger than 12 years.

    Science.gov (United States)

    Monini, Simonetta; Malagola, Caterina; Villa, Maria Pia; Tripodi, Caterina; Tarentini, Silvia; Malagnino, Irene; Marrone, Vania; Lazzarino, Antonio Ivan; Barbara, Maurizio

    2009-01-01

    To assess short- and long-term effects of rapid maxillary expansion (RME) on nasal flow in young children. Since RME has been reported to positively influence nasal obstruction in subjects with respiratory problems by reducing nasal resistance, a similar efficacy of RME could be expected in children with deciduous and/or mixed dentition who are affected by maxillary constriction and nasal obstruction from a different cause. Prospective study of children younger than 12 years, with different grades of malocclusion and oral breathing. Data included active anterior rhinomanometry in both the supine and orthostatic positions, as well as radiographic cephalometric measurements. Tertiary care university hospital. Data were prospectively collected from 2005 to 2007. Nasal flow and resistance were measured in 65 children younger than 12 years, with mixed or deciduous dentition and different grades of malocclusion and oral breathing. Efficacy of RME for resolution of maxillary constriction. After RME, an improvement of nasal flow and resistance has been recorded in patients, in the supine position, who presented both anterior and posterior obstruction. Less notable changes were shown in isolated forms of obstruction and in the orthostatic position. In cases of maxillary constriction and nasal airway obstruction, RME has proved to be efficient for the improvement of nasal respiration in children via a widening effect on the nasopharyngeal cavity.

  2. Influence of Orthodontic Rapid Maxillary Expansion on Nocturnal Enuresis in Children.

    Science.gov (United States)

    Hyla-Klekot, Lidia; Truszel, Marek; Paradysz, Andrzej; Postek-Stefańska, Lidia; Życzkowski, Marcin

    2015-01-01

    The etiology of nocturnal enuresis (NE) is multifactorial and has not been fully explained yet. New ways of treatment are constantly being investigated, including the rapid maxillary expansion (RME). A total of 41 patients diagnosed with NE were divided into two experimental groups: A and B. Group A included 16 children who have been treated with RME. Group B comprised 25 children who have not undertaken orthodontic treatment. Children from both groups have been monitored in monthly intervals, during a 12-month period, towards the intensification of NE. The comparative analysis of both groups has been conducted after 3 years of observation. Statistical analysis has shown a 4.5 times increase of the probability of reduction of NE in the case of the treated group in comparison with the group of children who have not undergone orthodontic treatment. Unfortunately, the chance of obtaining total dryness diminished proportionally to the higher degree of intensification of enuresis at the beginning of the test. RME can constitute an alternative method of NE treatment in children, irrespective of the occurrence of upper jaw narrowing.

  3. Morphologic changes of the palate after rapid maxillary expansion: a 3-dimensional computed tomography evaluation.

    Science.gov (United States)

    Phatouros, Andriana; Goonewardene, Mithran S

    2008-07-01

    The purpose of this retrospective study was to estimate the area change of the palate after rapid maxillary expansion (RME) in the early mixed dentition stage by using a 3-dimensional (3D) helical computed tomography (CT) scanning technique. In addition, linear changes in the maxillary arch were evaluated. The treated sample consisted of 43 children (mean age, 9 years 1 month) treated with a bonded RME appliance. The untreated control group consisted of 7 children (mean age, 9 years 3 months). Pretreatment and posttreatment dental casts were evaluated by using 3D helical CT scanning procedures. The Student t test was used to compare the linear, area, and angular differences between the treatment times. RME produced clinically significant increases in interdental widths across the canines, the deciduous first molars, and the permanent first molars in the maxillary arch. Significant increases in cross-sectional area were observed across the permanent first molars (15.3 mm(2)). There was marked variability in the buccal tipping of the permanent first molars. Three-dimensional helical CT scanning is an accurate and cost-effective method of assessing dental cast morphologic changes. It can also provide fast and accurate data acquisition and subsequent analysis.

  4. Influence of Orthodontic Rapid Maxillary Expansion on Nocturnal Enuresis in Children

    Directory of Open Access Journals (Sweden)

    Lidia Hyla-Klekot

    2015-01-01

    Full Text Available Background. The etiology of nocturnal enuresis (NE is multifactorial and has not been fully explained yet. New ways of treatment are constantly being investigated, including the rapid maxillary expansion (RME. Methods. A total of 41 patients diagnosed with NE were divided into two experimental groups: A and B. Group A included 16 children who have been treated with RME. Group B comprised 25 children who have not undertaken orthodontic treatment. Children from both groups have been monitored in monthly intervals, during a 12-month period, towards the intensification of NE. The comparative analysis of both groups has been conducted after 3 years of observation. Results. Statistical analysis has shown a 4.5 times increase of the probability of reduction of NE in the case of the treated group in comparison with the group of children who have not undergone orthodontic treatment. Unfortunately, the chance of obtaining total dryness diminished proportionally to the higher degree of intensification of enuresis at the beginning of the test. Conclusion. RME can constitute an alternative method of NE treatment in children, irrespective of the occurrence of upper jaw narrowing.

  5. Effects of rapid maxillary expansion on head posture, postural stability, and fall risk

    Directory of Open Access Journals (Sweden)

    Fatih Celebi

    2017-01-01

    Full Text Available Objective: The aim of this study was to investigate the effects of rapid maxillary expansion (RME on head posture, postural stability, and fall risk. Materials and Methods: A sample of 51 adolescent patients was randomly divided into two groups. In the first group, which consisted of 28 patients (15 females and 13 males, RME was performed as a part of routine orthodontic treatment. The remaining 23 individuals (12 females and 11 males served as the control group. Lateral cephalometric radiographs taken in natural head position, postural stability, and fall risk scores were obtained during the first visit. They were repeated on average 3.8 months and 3.5 months later for the study and control groups, respectively. The changes were analyzed using the Wilcoxon signed-rank test, paired samples t-test, Mann–Whitney U-test, and independent samples t-test. Results: As a result of RME, a statistically significant decrease was detected in the fall risk score (P < 0.05 in the study group, while the head position and postural stability remained unchanged. For the control group, no significant changes were observed in all measurements. Conclusions: The result of the present study suggests that RME has a capacity of improving fall risk.

  6. A bilinear elastic constitutive model applied for midpalatal suture behavior during rapid maxillary expansion

    Directory of Open Access Journals (Sweden)

    Larissa Carvalho Trojan Serpe

    Full Text Available Introduction : This study aims to evaluate the influence of the biomechanical behavior of the midpalatal suture (MPS during the rapid maxillary expansion (RME when modeled by the Finite Element Method. Methods Four simulation alternatives are discussed and, for each analysis, the suture is considered as a functional unit with a different mechanical behavior: (i without MPS elements, (ii MPS with Young's modulus (E equal to 1 MPa, (ii MPS with E equal to 0.01 MPa and (iv MPS with bilinear elastic behavior. Results The stress analysis showed that, when MPS is not considered in the model, stress peaks are reduced in magnitude and their distribution is restricted to a smaller area when compared to the model with the inclusion of MPS (E=1 MPa. The increased suture stiffness also has a direct influence on MPS displacements after 30 expander activations. Conclusion The consideration of the MPS in RME computer models influences greatly the calculated displacements between the suture bone ends, even as the stress levels in maxillary structures. Furthermore, as proposed for the described model, the elastic bilinear behavior assigned to MPS allows coherent prediction of stresses and displacements results, being a good representation for this suture overall behavior.

  7. Rapid expansion and pseudo spectral implementation for reverse time migration in VTI media

    KAUST Repository

    Pestana, Reynam C

    2012-04-24

    In isotropic media, we use the scalar acoustic wave equation to perform reverse time migration (RTM) of the recorded pressure wavefield data. In anisotropic media, P- and SV-waves are coupled, and the elastic wave equation should be used for RTM. For computational efficiency, a pseudo-acoustic wave equation is often used. This may be solved using a coupled system of second-order partial differential equations. We solve these using a pseudo spectral method and the rapid expansion method (REM) for the explicit time marching. This method generates a degenerate SV-wave in addition to the P-wave arrivals of interest. To avoid this problem, the elastic wave equation for vertical transversely isotropic (VTI) media can be split into separate wave equations for P- and SV-waves. These separate wave equations are stable, and they can be effectively used to model and migrate seismic data in VTI media where |ε- δ| is small. The artifact for the SV-wave has also been removed. The independent pseudo-differential wave equations can be solved one for each mode using the pseudo spectral method for the spatial derivatives and the REM for the explicit time advance of the wavefield. We show numerically stable and high-resolution modeling and RTM results for the pure P-wave mode in VTI media. © 2012 Sinopec Geophysical Research Institute.

  8. Rapid Maxillary Expansion After Alveolar Bone Grafting With rhBMP-2 in UCLP Evaluated by Means of CBCT

    NARCIS (Netherlands)

    Garib, D.; Miranda, F.; Sathler, R.; Kuijpers-Jagtman, A.M.; Aiello, C.A.

    2017-01-01

    OBJECTIVE: To demonstrate the feasibility of rapid maxillary expansion (RME) after alveolar bone grafting (ABG) in complete unilateral cleft lip, alveolus and palate (UCLP) without damage to the grafted area. SETTING: Hospital for Rehabilitation of Craniofacial Anomalies (HRAC), University of Sao

  9. LED phototherapy on midpalatal suture after rapid maxilla expansion: a Raman spectroscopic study

    Science.gov (United States)

    Rosa, Cristiane B.; Habib, Fernando Antonio L.; de Araújo, Telma M.; dos Santos, Jean N.; Cangussu, Maria Cristina T.; Barbosa, Artur Felipe S.; de Castro, Isabele Cardoso V.; Soares, Luiz Guilherme P.; Pinheiro, Antonio L. B.

    2015-03-01

    A quick bone formation after maxillary expansion would reduce treatment timeand the biomodulating effects of LED light could contribute for it. The aim of this study was to analyze the effect of LED phototherapy on the acceleration of bone formation at the midpalatal suture after maxilla expansion. Thirty rats divided into 6 groups were used on the study at 2 time points - 7 days: Control; Expansion; and Expansion + LED; and 14 days: Expansion; Expansion + LED in the first week; Expansion and LED in the first and second weeks. LED irradiation occurred at every 48 h during 2 weeks. Expansion was accomplished using a spatula and maintained with a triple helicoid of 0.020" stainless steel orthodontic wire. A LED light (λ850 ± 10nm, 150mW ± 10mW, spot of 0.5cm2, t=120 sec, SAEF of 18J/cm2) was applied in one point in the midpalatal suture immediately behind the upper incisors. Near infrared Raman spectroscopic analysis of the suture region was carried and data submitted to statistical analyzes (p≤0.05). Raman spectrum analysis demonstrated that irradiation increased hydroxyapatite in the midpalatal suture after expansion. The results of this indicate that LED irradiation; have a positive biomodulation contributing to the acceleration of bone formation in the midpalatal suture after expansion procedure.

  10. Mitochondrial phylogeography of moose (Alces alces): Late Pleistocene divergence and population expansion

    Science.gov (United States)

    Hundertmark, Kris J.; Shields, Gerald F.; Udina, Irina G.; Bowyer, R. Terry; Danilkin, Alexei A.; Schwartz, Charles C.

    2002-01-01

    We examined phylogeographic relationships of moose (Alces alces) worldwide to test the proposed existence of two geographic races and to infer the timing and extent of demographic processes underpinning the expansion of this species across the Northern Hemisphere in the late Pleistocene. Sequence variation within the left hypervariable domain of the control region occurred at low or moderate levels worldwide and was structured geographically. Partitioning of genetic variance among regions indicated that isolation by distance was the primary agent for differentiation of moose populations but does not support the existence of distinct eastern and western races. Levels of genetic variation and structure of phylogenetic trees identify Asia as the origin of all extant mitochondrial lineages. A recent coalescence is indicated, with the most recent common ancestor dating to the last ice age. Moose have undergone two episodes of population expansion, likely corresponding to the final interstade of the most recent ice age and the onset of the current interglacial. Timing of expansion for the population in the Yakutia–Manchuria region of eastern Asia indicates that it is one of the oldest populations of moose and may represent the source of founders of extant populations in North America, which were colonized within the last 15,000 years. Our data suggest an extended period of low population size or a severe bottleneck prior to the divergence and expansion of extant lineages and a recent, less-severe bottleneck among European lineages. Climate change during the last ice age, acting through contraction and expansion of moose habitat and the flooding of the Bering land bridge, undoubtedly was a key factor influencing the divergence and expansion of moose populations.

  11. Treatment resistant adolescent depression with upper airway resistance syndrome treated with rapid palatal expansion: a case report

    Directory of Open Access Journals (Sweden)

    Miller Paul

    2012-12-01

    Full Text Available Abstract Introduction To the best of our knowledge, this is the first report of a case of treatment-resistant depression in which the patient was evaluated for sleep disordered breathing as the cause and in which rapid palatal expansion to permanently treat the sleep disordered breathing produced a prolonged symptom-free period off medication. Case presentation An 18-year-old Caucasian man presented to our sleep disorders center with chronic severe depression that was no longer responsive to medication but that had recently responded to electroconvulsive therapy. Ancillary, persistent symptoms included mild insomnia, moderate to severe fatigue, mild sleepiness and severe anxiety treated with medication. Our patient had no history of snoring or witnessed apnea, but polysomnography was consistent with upper airway resistance syndrome. Although our patient did not have an orthodontic indication for rapid palatal expansion, rapid palatal expansion was performed as a treatment of his upper airway resistance syndrome. Following rapid palatal expansion, our patient experienced a marked improvement of his sleep quality, anxiety, fatigue and sleepiness. His improvement has been maintained off all psychotropic medication and his depression has remained in remission for approximately two years following his electroconvulsive therapy. Conclusions This case report introduces the possibility that unrecognized sleep disordered breathing may play a role in adolescent treatment-resistant depression. The symptoms of upper airway resistance syndrome are non-specific enough that every adolescent with depression, even those responding to medication, may have underlying sleep disordered breathing. In such patients, rapid palatal expansion, by widening the upper airway and improving airflow during sleep, may produce a prolonged improvement of symptoms and a tapering of medication. Psychiatrists treating adolescents may benefit from having another treatment option for

  12. Involvement of the Nonneuronal Cholinergic System in Bone Remodeling in Rat Midpalatal Suture after Rapid Maxillary Expansion

    Directory of Open Access Journals (Sweden)

    Xiaoxia Che

    2016-01-01

    Full Text Available Few studies sought to analyze the expression and function of the nonneuronal acetylcholine system in bone remodeling in vivo due to the lack of suitable models. We established a rat maxilla expansion model in which the midline palatine suture of the rat was rapidly expanded under mechanical force application, inducing tissue remodeling and new bone formation, which could be a suitable model to investigate the role of the nonneuronal acetylcholine system in bone remodeling in vivo. During the expansion, the expression pattern changes of the nonneuronal cholinergic system components and the mRNA levels of OPG/RANKL were detected by immunohistochemistry or real-time PCR. The value of the RANKL/OPG ratio significantly increased after 1 day of expansion, indicating dominant bone resorption induced by the mechanical stimulation; however after 3 days of expansion, the value of the RANKL/OPG ratio significantly decreased, suggesting a dominant role of the subsequent bone formation process. Increasing expression of Ach was detected after 3 days of expansion which indicated that ACh might play a role in bone formation. The mRNA expression levels of other components also showed observable changes during the expansion which confirmed the involvement of the nonneuronal cholinergic system in the process of bone remodeling in vivo. Further researches are still needed to figure out the detailed functions of the nonneuronal cholinergic system and its components.

  13. Involvement of the Nonneuronal Cholinergic System in Bone Remodeling in Rat Midpalatal Suture after Rapid Maxillary Expansion

    Science.gov (United States)

    Guo, Jie; Wang, Lue; Miao, Cong; Ge, Lihua; Tian, Zhenchuan; Wang, Jianhong

    2016-01-01

    Few studies sought to analyze the expression and function of the nonneuronal acetylcholine system in bone remodeling in vivo due to the lack of suitable models. We established a rat maxilla expansion model in which the midline palatine suture of the rat was rapidly expanded under mechanical force application, inducing tissue remodeling and new bone formation, which could be a suitable model to investigate the role of the nonneuronal acetylcholine system in bone remodeling in vivo. During the expansion, the expression pattern changes of the nonneuronal cholinergic system components and the mRNA levels of OPG/RANKL were detected by immunohistochemistry or real-time PCR. The value of the RANKL/OPG ratio significantly increased after 1 day of expansion, indicating dominant bone resorption induced by the mechanical stimulation; however after 3 days of expansion, the value of the RANKL/OPG ratio significantly decreased, suggesting a dominant role of the subsequent bone formation process. Increasing expression of Ach was detected after 3 days of expansion which indicated that ACh might play a role in bone formation. The mRNA expression levels of other components also showed observable changes during the expansion which confirmed the involvement of the nonneuronal cholinergic system in the process of bone remodeling in vivo. Further researches are still needed to figure out the detailed functions of the nonneuronal cholinergic system and its components. PMID:27478838

  14. Preparation and Characterization of Micronized Artemisinin via a Rapid Expansion of Supercritical Solutions (RESS Method

    Directory of Open Access Journals (Sweden)

    Xiaonan Zhang

    2012-04-01

    Full Text Available The particle sizes of pharmaceutical substances are important for their bioavailability. Bioavailability can be improved by reducing the particle size of the drug. In this study, artemisinin was micronized by the rapid expansion of supercritical solutions (RESS. The particle size of the unprocessed white needle-like artemisinin particles was 30 to 1200 µm. The optimum micronization conditions are determined as follows: extraction temperature of 62 °C, extraction pressure of 25 MPa, precipitation temperature 45 °C and nozzle diameter of 1000 μm. Under the optimum conditions, micronized artemisinin with a (mean particle size MPS of 550 nm is obtained. By analysis of variance (ANOVA, extraction temperature and pressure have significant effects on the MPS of the micronized artemisinin. The particle size of micronized artemisinin decreased with increasing extraction temperature and pressure. Moreover, the SEM, LC-MS, FTIR, DSC and XRD allowed the comparison between the crystalline initial state and the micronization particles obtained after the RESS process. The results showed that RESS process has not induced degradation of artemisinin and that processed artemisinin particles have lower crystallinity and melting point. The bulk density of artemisinin was determined before and after RESS process and the obtained results showed that it passes from an initial density of 0.554 to 0.128 g·cm−3 after the processing. The decrease in bulk density of the micronized powder can increase the liquidity of drug particles when they are applied for medicinal preparations. These results suggest micronized powder of artemisinin can be of great potential in drug delivery systems.

  15. Effect of low-level laser therapy after rapid maxillary expansion: a clinical investigation.

    Science.gov (United States)

    Garcia, Valentin Javier; Arnabat, J; Comesaña, Rafael; Kasem, Khaled; Ustrell, Josep Maria; Pasetto, Stefano; Segura, Oscar Pozuelo; ManzanaresCéspedes, Maria Cristina; Carvalho-Lobato, Patricia

    2016-08-01

    To evaluate the effectiveness low-level laser therapy (LLLT) on the repair of the mid palatal suture, after rapid maxillary expansion (RME). A single-operator, randomized single-blind placebo-controlled study was performed at the Orthodontic Department at the Dental Hospital of Bellvitge. Barcelona University, Hospitalet de Llobregat, Spain. Thirty-nine children (range 6-12 years old), completed RME and were randomized to receive active LLLT (n = 20) or placebo (n = 19). The laser parameters and dose were 660 nm, 100 mW, CW, InGaAlP laser, illuminated area 0.26 cm(2), 332 mW/cm(2), 60 s to four points along midpalatal suture, and 30 s to a point each side of the suture. A total of seven applications were made on days 1, 7, 14, 28, 42, 56, and 70 of the retention phase RME. A cone beam computed tomography (CBCT) scan was carried out on the day of the first laser treatment, and at day 75, a second CBCT scan was performed. Two radiologists synchronized the slices of two scans to be assessed. P = 0.05 was considered to be statistically significant. At day 75 of the suture, the irradiated patients presented a greater percentage of approximate zones in the anterior (p = 0.008) and posterior (p = 0.001) superior suture-and less approximation in the posterior superior suture (p = 0.040)-than the placebo group. LLLT appears to stimulate the repair process during retention phase after RME.

  16. Changes in pharyngeal aerobic microflora in oral breathers after palatal rapid expansion

    Directory of Open Access Journals (Sweden)

    Ripa Antonio

    2006-01-01

    Full Text Available Abstract Background The purpose of this study was to investigate in oral breathing children the qualitative and quantitative effects on aerobic and facultatively anaerobic oropharyngeal microflora of respiratory function improved by rapid palatal expansion (RPE. Methods In an open clinical trial, we studied 50 oral breathers, aged 8 to 14 years and suffering from both maxillary constriction and posterior cross-bite. At baseline, patients were examined by a single otorhinolaryngologist (ENT, confirming nasal obstruction in all subjects by posterior rhino-manometric test. Patients were evaluated three times by oropharyngeal swabs:1 at baseline (T = 0; 2 after palatal spreading out (T = 1; and 3 at the end of RPE treatment (T = 2. With regard to the microbiological aspect, the most common and potentially pathogenic oral microrganisms (i.e. Streptococcus pyogenes, Diplococcus pneumoniae, Staphylococcus aureus, Haemophilus spp, Branhamella catarrhalis, Klebsiella pneumoniae, Candida albicans were specifically detected in proper culture plates, isolated colonies were identified by means of biochemical tests and counted by calibrated loop. The data were analyzed by means of the following tests: Chi-square test, Fisher's exact test and Wilcoxon's test. Results After the use of RME there was a statistically significant decrease of Staphylococcus aureus stock at CFU/mLat T1(P = 0.0005; Z = -3,455 by Wilcoxon Rank test and T2 (P Conclusion Our data suggest that RPE therapy in oral breathers may strongly reduce the pathogenic aerobic and facultatively anaerobic microflora in the oral pharynx after a normalization of the upper airways function, and may reduce the risk of respiratory infections.

  17. Rapid maxillary expansion in children with Obstructive Sleep Apnoea Syndrome (OSAS).

    Science.gov (United States)

    Marino, A; Ranieri, R; Chiarotti, F; Villa, M P; Malagola, C

    2012-03-01

    to evaluate the effects of rapid maxillary expansion (RME) in a group of OSAS preschool children. Lateral cephalograms of 15 OSAS children (8 boys and 7 girls, age mean ± SD: 5.94 ± 1.64 years) were analysed at the start of treatment with RME (T0). All subjects were revaluated after a mean period of 1.57 ± 0.58 years (T1). At this time the sample was divided into 2 groups according to the change in the respiratory disturbance index (RDI): an improved group (I: 8 subjects) and a stationary/worsened group (SW: 7 subjects). Differences between I and SW children with respect to values of cephalometric variables at T0 and to variations between T0 and T1 were evaluated using Mann-Whitney U test. Differences between T0 and T1 values in the overall group of children and separately in I and SW groups were assessed using Wilcoxon test. At the start of treatment, the I group was characterised by more retrognathic jaws with lower values of SNA (p=0.055) and SNB (p=0.020) and higher age values (p=0.093) when compared to SW group. After treatment, the I group showed an increase in SNA and SNB angle significantly higher than SW group (p=0.004 and p=0.003, respectively). On the contrary, I and SW groups did not differ as for variation in the skeletal divergency and in the total facial height. OSAS preschool children with retrognathic jaws could benefit from RME treatment.

  18. Speleothem isotopic evidence for rapid human-induced expansion of grasslands in Madagascar at 890 CE

    Science.gov (United States)

    Burns, S. J.; Godfrey, L.; Faina, P.; McGee, D.; Hardt, B. F.; Ranivoharimanana, L.; Randrianasy, J.

    2015-12-01

    The degree to which human activity impacted the landscape, vegetation and fauna of Madagascar remains under debate. Since the early 1920's, the prevailing hypothesis has been that the savannah grasslands that now cover 70% of Madagascar were the result of deforestation, which has also been tied to the disappearance of much of the island's endemic megafauna. Other studies suggest that Madagascar's grasslands are largely natural and that megafaunal extinctions may be climatically induced, leading some authors to question the entire narrative of extensive alteration of the landscape by early human activity. We collected two stalagmites, M14-AB2 and M14-AB3, from Anjohibe Cave in northwestern Madagascar (15.55°S, 46.89°E, 100 masl). Age models were constructed using 8 U/Th age determinations from AB2 and 10 from AB3. The samples began to grow at ~500 CE and were active at the time of collection. Carbon and oxygen stable isotope ratios were measured on 266 samples from AB2 and 173 samples from AB3, yielding sub-decadal temporal resolution. A rapid, more than 10 per mil increase in stalagmite carbon stable isotope ratios documents an almost complete transformation of the landscape from one with a flora dominated by C3 plants to a C4 grassland system. This transformation, well replicated in both stalagmites, occurred at approximately 890 +/- 20 CE and was complete in 100 years. Further, relatively constant oxygen isotope ratios across the carbon isotope transition demonstrate that landscape alteration was not related to changes in climate. We hypothesize that the transformation was caused primarily by expansion of the use of fire by early inhabitants of Madagascar to promote agriculture and the growth of grass as fodder for cattle. The resulting loss of forest habitat very likely increased environmental pressures on Madagascar's megafauna and accelerated their disappearance.

  19. A systematic review of the effects of bone-borne surgical assisted rapid maxillary expansion.

    NARCIS (Netherlands)

    Verstraaten, J.; Kuijpers-Jagtman, A.M.; Mommaerts, M.Y.; Berge, S.J.; Nada, R.; Schols, J.G.J.H.

    2010-01-01

    INTRODUCTION: A systematic literature review was conducted to find out if bone-borne maxillary expansion with corticotomies is an effective and secure orthodontic/orthopaedic treatment modality, eliminating orthodontic and periodontal side effects of tooth-borne maxillary expansion with

  20. Finite-size effects on bacterial population expansion under controlled fow conditions

    CERN Document Server

    Tesser, Francesca; Clercx, Herman J H; Brunsveld, Luc; Toschi, Federico

    2016-01-01

    The expansion of biological species in natural environments is usually described as the combined effect of individual spatial dispersal and growth. In the case of aquatic ecosystems flow transport can also be extremely relevant as an extra, advection induced, dispersal factor. There is a lack of reproducible experimental studies on biological fronts of living organisms in controlled streaming habitats. It is thus not clear if, and to which extent, the current theoretical and experimental knowledge on advective-reactive-diffusive fronts for chemical reactions can also apply to the expansion of biological populations. We designed and assembled a dedicated microfluidic device to control and quantify the expansion of populations of $E.coli$ bacteria under both co-flowing and counter-flowing conditions, measuring the front speed at varying intensity of the imposed flow. At variance with respect to the case of autocatalytic reactions, we measure that almost irrespective of the counter-flow velocity, the front speed...

  1. Rapid Population Growth and its Implication for Malawi

    African Journals Online (AJOL)

    Worldwide concern has recently focused on the negative aspects of rapid population growth for the' future as regards natural and non-renewable re- sources, energy and the environment. A United. Nations sponsored international conference on. "Environment and Development" was held in Brazil. inJune 1992 to focus ...

  2. Population dynamics of a meiotic/mitotic expansion model for the fragile X syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Ashley, A.E.; Sherman, S.L. [Emory Univ. School of Medicine, Atlanta, GA (United States)

    1995-12-01

    A model to explain the mutational process and population dynamics of the fragile X syndrome is presented. The mutational mechanism was assumed to be a multi-pathway, multistep process. Expansion of CGG repeats was based on an underlying biological process and was assumed to occur at two time points: meiosis and early embryonic development (mitosis). Meiotic expansion was assumed to occur equally in oogenesis and spermatogenesis, while mitotic expansion was restricted to somatic, or constitutional, alleles of maternal origin. Testable hypotheses were predicted by this meiotic/mitotic model. First, parental origin of mutation is predicted to be associated with the risk of a woman to have a full-mutation child. Second, {open_quotes}contractions{close_quotes} seen in premutation male transmissions are predicted not to be true contractions in repeat size, but a consequence of the lack of mitotic expansion in paternally derived alleles. Third, a portion of full-mutation males should have full-mutation alleles in their sperm, due to the lack of complete selection against the full-mutation female. Fourth, a specific premutation-allele frequency distribution is predicted and differs from that based on models assuming only meiotic expansion. Last, it is predicted that {approximately}65 generations are required to achieve equilibrium, but this depends greatly on the expansion probabilities. 42 refs., 4 figs., 4 tabs.

  3. Rapid replacement of bridge deck expansion joints study - phase I : [tech transfer summary].

    Science.gov (United States)

    2014-12-01

    This initial research phase focused on documenting the current : means and methods of bridge expansion joint deterioration, : maintenance, and replacement and on identifying improvements : through all of the input gathered.

  4. Rapid maxillary expansion screws on the test bench--a pilot study.

    Science.gov (United States)

    Muchitsch, Alfred Peter; Wendl, B; Winsauer, H; Pichelmayer, M; Payer, M

    2011-06-01

    In order to apply high, short-term forces during rapid maxillary expansion (RME) to the sutures of the maxilla with minimum loss of force and without causing unwanted side-effects (dentoalveolar tipping, etc.), the appliance should be as rigid as possible. The retention arms of the RME screws, representing a particularly vulnerable and stressed weak point of RME appliances, were the focus of this laboratory technical study. Retention arms of 16 types of RME screws comprising four arms and one with eight arms were examined using a three-point bending test. According to their ability to absorb the applied bending loads, the screws were classified in product groups from 1 (highest) to 6 (lowest). Fifteen of the tested retention arms (stainless steel), despite having the same diameter (1.48-1.49 mm), differed up to 69.81 per cent between the highest (288.0 N) and lowest (169.6 N) maximum force parameters and up to 66.40 per cent between the highest (3325.9 N/mm(2)) and lowest (1998.7 N/mm(2)) maximum bending stress parameters. Due to optimum formability, though reduced rigidity, a titanium screw for nickel-sensitive patients (group 6) displayed the lowest force and bending tension values. The stainless steel double arms of the eight-arm screw device welded on both ends displayed the highest force data. The mean ductilities of the groups with the most and least rigid single steel arms differed by 22.77 per cent. Statistical analysis using the Pearson correlation coefficient revealed a significant indirect correlation between ductility and both maximum force (r = -0.780, P < 0.001) and maximum bending stress (r = -0.778, P < 0.001). The SUPERscrews, the Tiger Dental four-arm screw (group 1), and the eight-arm screw displayed the highest capacity to absorb an applied bending load. The screws in groups 3-6 appear acceptable for RME during the pre-pubertal period, whereas in the pubertal and post-pubertal period, groups 1 and 2 are sufficient. In early adulthood only the

  5. Immediate periodontal bone plate changes induced by rapid maxillary expansion in the early mixed dentition: CT findings

    Directory of Open Access Journals (Sweden)

    Daniela Gamba Garib

    2014-06-01

    Full Text Available OBJECTIVE: This study aimed at evaluating buccal and lingual bone plate changes caused by rapid maxillary expansion (RME in the mixed dentition by means of computed tomography (CT. METHODS: The sample comprised spiral CT exams taken from 22 mixed dentition patients from 6 to 9 years of age (mean age of 8.1 years presenting constricted maxillary arch treated with Haas-type expanders. Patients were submitted to spiral CT scan before expansion and after the screw activation period with a 30-day interval between T1 and T2. Multiplanar reconstruction was used to measure buccal and lingual bone plate thickness and buccal bone crest level of maxillary posterior deciduous and permanent teeth. Changes induced by expansion were evaluated using paired t test (p < 0.05. RESULTS: Thickness of buccal and lingual bone plates of posterior teeth remained unchanged during the expansion period, except for deciduous second molars which showed a slight reduction in bone thickness at the distal region of its buccal aspect. Buccal bone dehiscences were not observed in the supporting teeth after expansion. CONCLUSION: RME performed in mixed dentition did not produce immediate undesirable effects on periodontal bone tissues.

  6. Evaluation of the rapid and slow maxillary expansion using cone-beam computed tomography: a randomized clinical trial

    Directory of Open Access Journals (Sweden)

    Juliana da S. Pereira

    Full Text Available ABSTRACT OBJECTIVE: The aim of this randomized clinical trial was to evaluate the dental, dentoalveolar, and skeletal changes occurring right after the rapid maxillary expansion (RME and slow maxillary expansion (SME treatment using Haas-type expander. METHODS: All subjects performed cone-beam computed tomography (CBCT before installation of expanders (T1 and right after screw stabilization (T2. Patients who did not follow the research parameters were excluded. The final sample resulted in 21 patients in RME group (mean age of 8.43 years and 16 patients in SME group (mean age of 8.70 years. Based on the skewness and kurtosis statistics, the variables were judged to be normally distributed and paired t-test and student t-test were performed at significance level of 5%. RESULTS: Intermolar angle changed significantly due to treatment and RME showed greater buccal tipping than SME. RME showed significant changes in other four measurements due to treatment: maxilla moved forward and mandible showed backward rotation and, at transversal level both skeletal and dentoalveolar showed significant changes due to maxillary expansion. SME showed significant dentoalveolar changes due to maxillary expansion. CONCLUSIONS: Only intermolar angle showed significant difference between the two modalities of maxillary expansion with greater buccal tipping for RME. Also, RME produced skeletal maxillary expansion and SME did not. Both maxillary expansion modalities were efficient to promote transversal gain at dentoalveolar level. Sagittal and vertical measurements did not show differences between groups, but RME promoted a forward movement of the maxilla and backward rotation of the mandible.

  7. Evaluating population expansion of black bears using spatial capture-recapture

    Science.gov (United States)

    Sun, Catherine C.; Fuller, Angela K.; Hare, Matthew P.; Hurst, Jeremy E.

    2017-01-01

    The population of American black bears (Ursus americanus) in southern New York, USA has been growing and expanding in range since the 1990s. This has motivated a need to anticipate future patterns of range expansion. We conducted a non-invasive, genetic, spatial capture-recapture (SCR) study to estimate black bear density and identify spatial patterns of population density that are potentially associated with range expansion. We collected hair samples in a 2,519-km2 study area in southern New York with barbed-wire hair snares and identified individuals and measured genetic diversity using 7 microsatellite loci and 1 sex-linked marker. We estimated a mean density of black bears in the region of 13.7 bears/100 km2, and detected a slight latitudinal gradient in density consistent with the documented range expansion. However, elevation and the amounts of forest, crop, and developed landcover types did not influence density, suggesting that bears are using a diversity of resources in this heterogeneous landscape outside their previously described distribution. These results provide the first robust baseline estimates for population density and distribution associated with different landcover types in the expanded bear range. Further, genetic diversity was comparable to that of non-expanding black bear populations in the eastern United States, and in combination with the latitudinal density gradient, suggest that the study area is not at the colonizing front of the range expansion. In addition, the diversity of landcover types used by bears in the study area implies a possible lack of constraints for further northern expansion of the black bear range. Our non-invasive, genetic, spatial capture-recapture approach has utility for studying populations of other species that may be expanding in range because SCR allows for the testing of explicit, spatial ecological hypotheses. 

  8. Non-surgical treatment of transverse deficiency in adults using Microimplant-assisted Rapid Palatal Expansion (MARPE).

    Science.gov (United States)

    Brunetto, Daniel Paludo; Sant'Anna, Eduardo Franzzotti; Machado, Andre Wilson; Moon, Won

    2017-02-01

    Maxillary transverse deficiency is a highly prevalent malocclusion present in all age groups, from primary to permanent dentition. If not treated on time, it can aggravate and evolve to a more complex malocclusion, hindering facial growth and development. Aside from the occlusal consequences, the deficiency can bring about serious respiratory problems as well, due to the consequent nasal constriction usually associated. In growing patients, this condition can be easily handled with a conventional rapid palatal expansion. However, mature patients are frequently subjected to a more invasive procedure, the surgically-assisted rapid palatal expansion (SARPE). More recently, researches have demonstrated that it is possible to expand the maxilla in grown patients without performing osteotomies, but using microimplants anchorage instead. This novel technique is called microimplant-assisted rapid palatal expansion (MARPE). The aim of the present article was to demonstrate and discuss a MARPE technique developed by Dr. Won Moon and colleagues at University of California - Los Angeles (UCLA). All laboratory and clinical steps needed for its correct execution are thoroughly described. For better comprehension, a mature patient case is reported, detailing all the treatment progress and results obtained. It was concluded that the demonstrated technique could be an interesting alternative to SARPE in the majority of non-growing patients with maxillary transverse deficiency. The present patient showed important occlusal and respiratory benefits following the procedure, without requiring any surgical intervention.

  9. Non-surgical treatment of transverse deficiency in adults using Microimplant-assisted Rapid Palatal Expansion (MARPE

    Directory of Open Access Journals (Sweden)

    Daniel Paludo Brunetto

    Full Text Available ABSTRACT Introduction: Maxillary transverse deficiency is a highly prevalent malocclusion present in all age groups, from primary to permanent dentition. If not treated on time, it can aggravate and evolve to a more complex malocclusion, hindering facial growth and development. Aside from the occlusal consequences, the deficiency can bring about serious respiratory problems as well, due to the consequent nasal constriction usually associated. In growing patients, this condition can be easily handled with a conventional rapid palatal expansion. However, mature patients are frequently subjected to a more invasive procedure, the surgically-assisted rapid palatal expansion (SARPE. More recently, researches have demonstrated that it is possible to expand the maxilla in grown patients without performing osteotomies, but using microimplants anchorage instead. This novel technique is called microimplant-assisted rapid palatal expansion (MARPE. Objective: The aim of the present article was to demonstrate and discuss a MARPE technique developed by Dr. Won Moon and colleagues at University of California - Los Angeles (UCLA. Methods: All laboratory and clinical steps needed for its correct execution are thoroughly described. For better comprehension, a mature patient case is reported, detailing all the treatment progress and results obtained. Conclusion: It was concluded that the demonstrated technique could be an interesting alternative to SARPE in the majority of non-growing patients with maxillary transverse deficiency. The present patient showed important occlusal and respiratory benefits following the procedure, without requiring any surgical intervention.

  10. C9ORF72 hexanucleotide repeat expansions in the Italian sporadic ALS population

    Science.gov (United States)

    Sabatelli, Mario; Conforti, Francesca Luisa; Zollino, Marcella; Mora, Gabriele; Monsurrò, Maria Rosaria; Volanti, Paolo; Marinou, Kalliopi; Salvi, Fabrizio; Corbo, Massimo; Giannini, Fabio; Battistini, Stefania; Penco, Silvana; Lunetta, Christian; Quattrone, Aldo; Gambardella, Antonio; Logroscino, Giancarlo; Simone, Isabella; Bartolomei, Ilaria; Pisano, Fabrizio; Tedeschi, Gioacchino; Conte, Amelia; Spataro, Rossella; La Bella, Vincenzo; Caponnetto, Claudia; Mancardi, Gianluigi; Mandich, Paola; Sola, Patrizia; Mandrioli, Jessica; Renton, Alan E.; Majounie, Elisa; Abramzon, Yevgeniya; Marrosu, Francesco; Marrosu, Maria Giovanna; Murru, Maria Rita; Sotgiu, Maria Alessandra; Pugliatti, Maura; Rodolico, Carmelo; Moglia, Cristina; Calvo, Andrea; Ossola, Irene; Brunetti, Maura; Traynor, Bryan J.; Borghero, Giuseppe; Restagno, Gabriella; Chiò, Adriano

    2012-01-01

    It has been recently reported that a large proportion of patients with familial amyotrophic lateral sclerosis (familial ALS) and frontotemporal dementia (FTD) are associated with a hexanucleotide (GGGGCC) repeat expansion in the first intron of C9ORF72. We have assessed 1,757 Italian sporadic ALS cases, 133 from Sardinia, 101 from Sicily, and 1,523 from mainland Italy. Sixty (3.7%) of 1,624 mainland Italians and Sicilians and 9 (6.8%) of the 133 Sardinian sporadic ALS cases carried the pathogenic repeat expansion. None of the 619 regionally-matched control samples (1,238 chromosomes) carried the expansion. Twenty-five cases (36.2%) had behavioral FTD in addition to ALS. FTD or unspecified dementia was also detected in 19 pedigrees (27.5%) in first-degree relatives of ALS patients. Cases carrying the C9ORF72 hexanucleotide expansion survived one year less than cases who did not carry this mutation. In conclusion, we found that C9ORF72 hexanucloetide repeat expansions represents a sizeable proportion of apparent sporadic ALS in the Italian and Sardinian population, representing by far the commonest mutation in Italy and the second more common in Sardinia. PMID:22418734

  11. Investigation of char strength and expansion properties of an intumescent coating exposed to rapid heating rates

    DEFF Research Database (Denmark)

    Nørgaard, Kristian Petersen; Dam-Johansen, Kim; Català, Pere

    2013-01-01

    , char properties, measured at room temperature, were dependent on the preceding storage conditions (in air or in a desiccator). The char was found to have the highest mechanical strength against compression in the outer crust facing the heat source. For thin (147μm) free coating films, a tendency...... with respect to the mechanical resistance against compression, degree of expansion, and residual mass fraction. Experimental results show that when using this type of shock heating, the mechanical resistance of the char against compression cannot meaningfully be correlated to the expansion factor. In addition...

  12. Major population expansion of East Asians began before neolithic time: evidence of mtDNA genomes.

    Science.gov (United States)

    Zheng, Hong-Xiang; Yan, Shi; Qin, Zhen-Dong; Wang, Yi; Tan, Jing-Ze; Li, Hui; Jin, Li

    2011-01-01

    It is a major question in archaeology and anthropology whether human populations started to grow primarily after the advent of agriculture, i.e., the Neolithic time, especially in East Asia, which was one of the centers of ancient agricultural civilization. To answer this question requires an accurate estimation of the time of lineage expansion as well as that of population expansion in a population sample without ascertainment bias. In this study, we analyzed all available mtDNA genomes of East Asians ascertained by random sampling, a total of 367 complete mtDNA sequences generated by the 1000 Genome Project, including 249 Chinese (CHB, CHD, and CHS) and 118 Japanese (JPT). We found that major mtDNA lineages underwent expansions, all of which, except for two JPT-specific lineages, including D4, D4b2b, D4a, D4j, D5a2a, A, N9a, F1a1'4, F2, B4, B4a, G2a1 and M7b1'2'4, occurred before 10 kya, i.e., before the Neolithic time (symbolized by Dadiwan Culture at 7.9 kya) in East Asia. Consistent to this observation, the further analysis showed that the population expansion in East Asia started at 13 kya and lasted until 4 kya. The results suggest that the population growth in East Asia constituted a need for the introduction of agriculture and might be one of the driving forces that led to the further development of agriculture.

  13. Relapse and stability of surgically assisted rapid maxillary expansion, an anatomical biomechanical study

    NARCIS (Netherlands)

    Koudstaal, M.J.; Smeets, J.B.J.; Kleinrensink, G.J.; Schulten, A.J.M.; van der Wal, K.G.H.

    2009-01-01

    Purpose: This anatomic biomechanical study was undertaken to gain insight into the underlining mechanism of tipping of the maxillary segments during transverse expansion using tooth-borne and bone-borne distraction devices. Materials and Methods: An anatomic biomechanical study was performed on 10

  14. Rapid range expansion in the Great Plains narrow-mouthed toad (Gastrophryne olivacea) and a revised taxonomy for North American microhylids.

    Science.gov (United States)

    Streicher, Jeffrey W; Cox, Christian L; Campbell, Jonathan A; Smith, Eric N; de Sá, Rafael O

    2012-09-01

    We investigated genetic variation within the Great Plains narrow-mouthed toad, Gastrophryne olivacea, across its geographic range in the United States and Mexico. An analysis of mitochondrial DNA (mtDNA) from 105 frogs revealed remarkably low levels of genetic diversity in individuals inhabiting the central United States and northern Mexico. We found that this widespread matrilineal lineage is divergent (ca. 2% in mtDNA) from haplotypes that originate from the western United States and western coast of Mexico. Using a dataset that included all five species of Gastrophryne and both species of the closely related genus Hypopachus, we investigated the phylogenetic placement of G. olivacea. This analysis recovered strong support that G. olivacea, the tropically distributed G. elegans, and the temperately distributed G. carolinensis constitute a monophyletic assemblage. However, the placement of G. pictiventris and G. usta render Gastrophryne paraphyletic with respect to Hypopachus. To complement our mitochondrial analysis, we examined a small fragment of nuclear DNA and recovered consistent patterns. In light of our findings we recommend (1) the resurrection of the nomen G. mazatlanensisTaylor (1943) for the disjunct western clade of G. olivacea and (2) the tentative placement of G. pictiventris and G. usta in Hypopachus. To explore possible scenarios leading to low levels of genetic diversity in G. olivacea, we used mismatch distributions and Bayesian Skyline plots to examine historic population expansion and demography. Collectively these analyses suggest that G. olivacea rapidly expanded in effective population size and geographic range during the late Pleistocene or early Holocene. This hypothesis is consistent with fossil data from northern localities and contemporary observations that suggest ongoing northern expansion. Given our findings, we suspect that the rapid range expansion of G. olivacea may have been facilitated by ecological associations with open

  15. Can rapid maxillary expansion cause auditory improvement in children and adolescents with hearing loss? A systematic review.

    Science.gov (United States)

    Fagundes, Nathalia Carolina Fernandes; Rabello, Nicole Melres; Maia, Lucianne Cople; Normando, David; Mello, Karina Corrêa Flexa Ribeiro

    2017-11-01

    To evaluate whether the use of palatal expansion techniques can influence hearing loss in children and adolescents with previous hearing impairment. Electronic searches in PubMed, Scopus, Web of Science, The Cochrane Library, Lilacs, OpenGrey, and Google Scholar were performed with a controlled vocabulary and free-text terms relating to palatal expansion and hearing loss. No language or time restrictions were imposed. Clinical trials that focused on human patients treated with rapid or semirapid maxillary expansion in children and teenagers with hearing loss were included. Data extraction was undertaken by two authors, with conflict resolution by a third author. Risk of bias assessment and data extraction were performed on the selected studies. Seventy-four citations were retrieved by the search. Initially, 12 studies were selected according to the eligibility criteria, but three studies were excluded because of the presence of adults, absence of hearing level evaluation, and oversampling, resulting in nine studies. The mean improvement in hearing levels varied from 2 to 19 dB among the studies. The risk of bias varied from low to moderate risk. The evidence indicated that there was a hearing improvement after maxillary expansion in patients with hearing loss in the evaluated studies, although more controlled and randomized studies are necessary to investigate this issue further.

  16. The statistics of genetic diversity in rapidly adapting populations.

    Science.gov (United States)

    Desai, Michael

    2013-03-01

    Evolutionary adaptation is driven by the accumulation of beneficial mutations, but the sequence-level dynamics of this process are poorly understood. The traditional view is that adaptation is dominated by rare beneficial ``driver'' mutations that occur sporadically and then rapidly increase in frequency until they fix (a ``selective sweep''). Yet in microbial populations, multiple beneficial mutations are often present simultaneously. Selection cannot act on each mutation independently, but only on linked combinations. This means that the fate of any mutation depends on a complex interplay between its own fitness effect, the genomic background in which it arises, and the rest of the sequence variation in the population. The balance between these factors determines which mutations fix, the patterns of sequence diversity within populations, and the degree to which evolution in replicate populations will follow parallel (or divergent) trajectories at the sequence level. Earlier work has uncovered signatures of these effects, but the dynamics of genomic sequence evolution in adapting microbial populations have not yet been directly observed. In this talk, I will describe how full-genome whole-population sequencing can be used to provide a detailed view of these dynamics at high temporal resolution over 1000 generations in 40 adapting Saccharomyces cerevisiaepopulations. This data shows how patterns of sequence evolution are driven by a balance between chance interference and hitchhiking effects, which increase stochastic variation in evolutionary outcomes, and the deterministic action of selection on individual mutations, which favors parallel solutions in replicate populations.

  17. Effect of maxillary protraction with alternating rapid palatal expansion and constriction vs expansion alone in maxillary retrusive patients: a single-center, randomized controlled trial.

    Science.gov (United States)

    Liu, Weitao; Zhou, Yanheng; Wang, Xuedong; Liu, Dawei; Zhou, Shaonan

    2015-10-01

    The objective of this randomized controlled trial was to investigate the effects of facemask protraction combined with alternating rapid palatal expansion and constriction (RPE/C) vs rapid palatal expansion (RPE) alone in the early treatment of maxillary retrusive patients. Patients with a midface deficiency were recruited and randomly allocated into either the control group (RPE) or the intervention group (RPE/C). Eligibility criteria included the following: age 7 to 13 years old, Class III malocclusion, anterior crossbite, ANB less than 0°, Wits appraisal less than -2 mm, A-Np less than 0 mm, and no cleft of lip or palate. The primary outcome was the degree of maxillary forward movement after treatment. The secondary outcomes were the changes of the other cephalometric variables after treatment and the treatment time. Simple randomization was carried out using a random number table at the beginning of the study. Envelopes containing the grouping information were used to ensure allocation concealment from the researchers. Blinding was applicable for cephalometric analysis only. Hyrax palatal expanders and facemask maxillary protraction were used in all patients. Patients in the RPE group were treated with rapid palatal expansion for 1 week. Patients in the RPE/C group were treated with RPE/C for 7 weeks. The expansion or constriction rate was 1 mm per day. Cephalometric analysis with traditional cephalometric measurements and an x-y coordinate system were used to compare the pretreatment and posttreatment cephalometric radiographs. Independent t tests were used to compare the data between the 2 groups. A total of 44 patients were randomized to either the RPE group or the RPE/C group in a 1:1 ratio. One subject in the RPE group was lost to follow-up during the treatment. Per-protocol analysis was used. All the other 43 patients reached the treatment completion criteria and were analyzed (RPE group: n = 21; RPE/C group: n = 22). The average protraction time was 10

  18. Popping expansion and yield responses of popcorn cultivars under different row spacings and plant populations

    Directory of Open Access Journals (Sweden)

    José Antonio de Souza Rossato Junior

    2013-12-01

    Full Text Available The objective of this work was to evaluate the agronomic traits and the popping expansion index of three Brazilian popcorn cultivars under different row spacings and plant populations. The trials were performed during two crop seasons, under field conditions. The experimental design used was a randomized complete block, in a split-split plot, with 27 treatments and four replicates. Treatments were represented in a triple factorial arrangement: three row spacings (0.40, 0.60, and 0.80 m, three plant populations (40,000, 60,000, and 80,000 plants per hectare, and three popcorn cultivars (IAC-TC 01, IAC 12, and Zelia. The increase in plant population causes a reduction in the number of grains per ear, lower prolificacy, and grain weight loss. Cultivar grain yield is affected by row spacing and popcorn plant population. Cultivar IAC 12 shows highest grain yield under row spacings of 0.40 and 0.60 m and plant population between 60,000 and 80,000 plants per hectare. The popping expansion index is not affected by row spacing or plant population.

  19. Effects of palate depth, modified arm shape, and anchor screw on rapid maxillary expansion: a finite element analysis.

    Science.gov (United States)

    Matsuyama, Yosuke; Motoyoshi, Mitsuru; Tsurumachi, Niina; Shimizu, Noriyoshi

    2015-04-01

    This study examined the effects of palate depth, modifications of the arm shape, and anchor screw placement in the mid-palatal area on rapid maxillary expansion (RME) using finite element (FE) analysis. Three-dimensional FE models were constructed that included the maxilla (cortical and cancellous bone), maxillary sinus, maxillary first molar and first premolar, periodontal membrane, and an RME appliance with arms, bands, and anchor screws. The expansion screws were activated 0.2mm transversely. The deepest palate model had the smallest lateral displacement of the tooth and expansion of the mid-palatal suture and the greatest strain of the arm among the models with different palate heights. The model with a larger diameter arm had the smallest arm strain among the models with various arm shapes. The model with an anchor screw had the greatest lateral displacement of the tooth and expansion of the mid-palatal suture among all models. For a deeper palate, the arm strain increased and the effect of RME decreased. Modified arm shapes such as a larger diameter arm, arms connected by a diagonal wire, a straight arm, and a shorter arm efficiently expanded the maxillary dental arch. Anchor screws increased the effect of RME, generated more and closer bodily movement of the tooth, and parallel expansion of the mid-palatal suture. The model with an anchor screw without arms decreased the displacement of the teeth compared to the models with arms, so the arms are necessary for effective RME. © The Author 2014. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  20. Effects of strontium ranelate on bone formation in the mid-palatal suture after rapid maxillary expansion

    Directory of Open Access Journals (Sweden)

    Zhao SY

    2015-05-01

    Full Text Available Shuya Zhao,1,* Xuxia Wang,2,* Na Li,3 Yun Chen,1 Yuran Su,1 Jun Zhang1 1Department of Orthodontics, 2Department of Oral and Maxillofacial Surgery, Faculty of Stomatology, Shandong University; 3Department of Orthodontics, Shandong Provincial Qianfoshan Hospital, Jinan, People’s Republic of China *These authors contributed equally to this work Background: The aim of this experimental study was to investigate the effects of strontium ranelate on bone regeneration in the mid-palatal suture in response to rapid maxillary expansion (RME.Methods: Thirty-six male 6-week-old Wistar rats were randomly divided into three groups, ie, an expansion only (EO group, an expansion plus strontium ranelate (SE group, and a control group. An orthodontic appliance was set between the right and left upper molars of rats with an initial expansive force of 0.98 N. Rats in the SE group were administered strontium ranelate (600 mg/kg body weight and then euthanized in batches on days 4, 7, and 10. Morphological changes in the mid-palatal suture were investigated using micro-computed tomography and hematoxylin and eosin staining after RME. Bone morphogenetic protein-2 expression in the suture was also examined to evaluate bone formation in the mid-palatal suture. Image-Pro Plus software was then used to determine the mean optical density of the immunohistochemical images. Analysis of variance was used for statistical evaluation at the P<0.05 level.Results: With expansive force, the mid-palatal suture was expanded, but there was no statistically significant difference (P>0.05 between the SE and EO groups. The bone volume of the suture decreased after RME, but was higher in the SE group than in the EO group on days 7 and 10. Further, expression of bone morphogenetic protein-2 in the SE group was higher than in the other two groups (P<0.05.Conclusion: Strontium ranelate may hasten new bone formation in the expanded mid-palatal suture, which may be therapeutically

  1. Long-term outcome of skeletal Class II Division 1 malocclusion treated with rapid palatal expansion and Kloehn cervical headgear.

    Science.gov (United States)

    Filho, Roberto M A Lima; Lima, Anna Letícia

    2003-08-01

    The treatment of a patient with a skeletal Class II Division 1 malocclusion, with excessive overjet, complete overbite, airway obstruction, and severe arch length deficiency in the mandibular dental arch, is presented. The maxilla was narrow compared with the mandible, and the posterior teeth were compensated, with the maxillary teeth inclined buccally and the mandibular teeth inclined lingually. The palatal vault was extremely high. Treatment included rapid palatal expansion to correct the transverse maxillary deficiency and Kloehn cervical headgear to correct the anteroposterior skeletal discrepancy. Long-term stability (12-year follow-up) is reported.

  2. Mitochondrial DNA variation of the common hippopotamus: evidence for a recent population expansion

    DEFF Research Database (Denmark)

    Okello, John Bosco A.; Nyakaana, Silvester; Masembe, C.

    2005-01-01

    Mitochondrial DNA control region sequence variation was obtained and the population history of the common hippopotamus was inferred from 109 individuals from 13 localities covering six populations in sub-Saharan Africa. In all, 100 haplotypes were defined, of which 98 were locality specific...... was observed in the total data set (FST=0.138; P=0.001), and at the population level, patterns of differentiation support previously suggested hippopotamus subspecies designations (FCT=0.103; P=0.015). Evidence that the common hippopotamus recently expanded were revealed by: (i) lack of clear geographical......-frequency spectra and neutrality statistics performed at subspecies level also supported expansion of Hippopotamus amphibius across Africa. We interpret observed common hippopotamus population history in terms of Pleistocene drainage overflow and suggest recognising the three subspecies that were sampled...

  3. Remodelling of the palatal dome following rapid maxillary expansion (RME): laser scan-quantifications during a low growth period.

    Science.gov (United States)

    Muchitsch, A P; Winsauer, H; Wendl, B; Pichelmayer, M; Kuljuh, E; Szalay, A; Muchitsch, M

    2012-02-01

    To evaluate changes in the palatal vault after rapid maxillary expansion (RME) with bonded splint appliances. The sample comprised 24 children (12 boys and 12 girls) with mixed dentition (mean age 8.3 years; range 6.4-10.4 years). Following expansion, the splint appliance was used as a retainer for 6 months and then removed. Study casts were taken before RME (T0) and when the appliance was removed (T1). Then, 3D laser scans were taken to build complete 3D jaw models. Frontal cross sections were constructed at 53-63, 55-65 and 16-26, exported as coordinates, and finite element calculated to quantify their area, width and height. Maxillary length was also determined. Paired t-tests indicated statistically significant increases in the average palatal width (T1-T0=6.53-6.79 mm) and cross-sectional area (T1-T0=20.39-21.39 mm2) after RME (p0.99 (pmaxillary expansion distinctly increased mean palatal widths and cross-sectional areas. However, palatal height (55-65) and maxillary length decreased to a small extent. © 2012 John Wiley & Sons A/S.

  4. Cone-beam computed tomography evaluation of dental, skeletal, and alveolar bone changes associated with bonded rapid maxillary expansion

    Directory of Open Access Journals (Sweden)

    Namrata Dogra

    2016-01-01

    Full Text Available Aims and Objectives: To evaluate skeletal changes in maxilla and its surrounding structures, changes in the maxillary dentition and maxillary alveolar bone changes produced by bonded rapid maxillary expansion (RME using cone-beam computed tomography (CBCT. Materials and Methods: The sample consisted of 10 patients (6 males and 4 females with age range 12 to 15 years treated with bonded RME. CBCT scans were performed at T1 (pretreatment and at T2 (immediately after expansion to evaluate the dental, skeletal, and alveolar bone changes. Results: RME treatment increased the overall skeletal parameters such as interorbital, zygomatic, nasal, and maxillary widths. Significant increases in buccal maxillary width was observed at first premolar, second premolar, and first molar level. There was a significant increase in arch width both on the palatal side and on the buccal side. Significant tipping of right and left maxillary first molars was seen. There were significant reductions in buccal bone plate thickness and increase in palatal bone plate thickness. Conclusions: Total expansion achieved with RME was a combination of dental, skeletal and alveolar bone changes. At the first molar level, 28.45% orthopedic, 16.03% alveolar bone bending, and 55.5% orthodontic changes were observed.

  5. Rapid Cycling Genomic Selection in a Multiparental Tropical Maize Population

    Directory of Open Access Journals (Sweden)

    Xuecai Zhang

    2017-07-01

    Full Text Available Genomic selection (GS increases genetic gain by reducing the length of the selection cycle, as has been exemplified in maize using rapid cycling recombination of biparental populations. However, no results of GS applied to maize multi-parental populations have been reported so far. This study is the first to show realized genetic gains of rapid cycling genomic selection (RCGS for four recombination cycles in a multi-parental tropical maize population. Eighteen elite tropical maize lines were intercrossed twice, and self-pollinated once, to form the cycle 0 (C0 training population. A total of 1000 ear-to-row C0 families was genotyped with 955,690 genotyping-by-sequencing SNP markers; their testcrosses were phenotyped at four optimal locations in Mexico to form the training population. Individuals from families with the best plant types, maturity, and grain yield were selected and intermated to form RCGS cycle 1 (C1. Predictions of the genotyped individuals forming cycle C1 were made, and the best predicted grain yielders were selected as parents of C2; this was repeated for more cycles (C2, C3, and C4, thereby achieving two cycles per year. Multi-environment trials of individuals from populations C0, C1, C2, C3, and C4, together with four benchmark checks were evaluated at two locations in Mexico. Results indicated that realized grain yield from C1 to C4 reached 0.225 ton ha−1 per cycle, which is equivalent to 0.100 ton ha−1 yr−1 over a 4.5-yr breeding period from the initial cross to the last cycle. Compared with the original 18 parents used to form cycle 0 (C0, genetic diversity narrowed only slightly during the last GS cycles (C3 and C4. Results indicate that, in tropical maize multi-parental breeding populations, RCGS can be an effective breeding strategy for simultaneously conserving genetic diversity and achieving high genetic gains in a short period of time.

  6. Measurement of Rapid Protein Diffusion in the Cytoplasm by Photo-Converted Intensity Profile Expansion

    Directory of Open Access Journals (Sweden)

    Rotem Gura Sadovsky

    2017-03-01

    Full Text Available The fluorescence microscopy methods presently used to characterize protein motion in cells infer protein motion from indirect observables, rather than measuring protein motion directly. Operationalizing these methods requires expertise that can constitute a barrier to their broad utilization. Here, we have developed PIPE (photo-converted intensity profile expansion to directly measure the motion of tagged proteins and quantify it using an effective diffusion coefficient. PIPE works by pulsing photo-convertible fluorescent proteins, generating a peaked fluorescence signal at the pulsed region, and analyzing the spatial expansion of the signal. We demonstrate PIPE’s success in measuring accurate diffusion coefficients in silico and in vitro and compare effective diffusion coefficients of native cellular proteins and free fluorophores in vivo. We apply PIPE to measure diffusion anomality in the cell and use it to distinguish free fluorophores from native cellular proteins. PIPE’s direct measurement and ease of use make it appealing for cell biologists.

  7. The effect of surgically assisted rapid maxillary expansion on sleep architecture: an exploratory risk study in healthy young adults.

    Science.gov (United States)

    Bach, N; Tuomilehto, H; Gauthier, C; Papadakis, A; Remise, C; Lavigne, F; Lavigne, G J; Huynh, N

    2013-11-01

    Maxillary transverse deficiencies (MTD) cause malocclusions. Rapid maxillary expansion treatment is commonly used treatment for correcting such deficiencies and has been found to be effective in improving respiration and sleep architecture in children with obstructive sleep apnoea (OSA). However, thus far, the effect of surgically assisted rapid maxillary expansion (SARME) treatment on sleep architecture and breathing of normal subjects has not been assessed. We hypothesised that sleep quality will improve after maxillary expansion treatment. The objective of this study is to access the effect of maxillary expansion treatment on sleep structure and respiratory functions in healthy young adults with severe MTD. This is a prospective and exploratory clinical study. Twenty-eight consecutive young adult patients (15 males and 13 females, mean age 20·6 ± 5·8 years) presenting with severe MTD at the orthodontic examination were recruited into the study. All the participants underwent a standardised SARME procedure (mean expansion 6·5 ± 1·8 and 8·2 ± 1·8 mm, intercanine and intermolar distance, respectively) to correct malocclusion caused by MTD. An overnight in-laboratory polysomnography, before and after the treatment, was performed. The mean follow-up time was 9 months. The main outcome parameters were the changes in sleep architecture, including sleep stages, arousals, slow-wave activity (SWA) and respiratory variables. Before surgery, young adult patients with MTD presented no evidence of sleep breathing problems. At baseline sleep recording, 7 of 28 (25%) had apnoea-hypopnoea index (AHI) ≥ 5 events per hour. No negative effect of the SARME was observed in questionnaires or sleep laboratory parameters. In the patients with a higher baseline AHI (AHI ≥ 5 h of sleep), we observed a reduction in AHI after surgical treatment (P = 0·028). SARME did not have a negative effect on any sleep or respiration parameters in healthy young individuals

  8. Dentoskeletal effects of maxillary protraction in cleft patients with repetitive weekly protocol of alternate rapid maxillary expansions and constrictions.

    Science.gov (United States)

    da Luz Vieira, Gustavo; de Menezes, Luciane Macedo; de Lima, Eduardo Martinelli S; Rizzatto, Susana

    2009-07-01

    To evaluate the amount of maxillary protraction with face mask in complete unilateral cleft lip and palate patients submitted to two distinct rapid maxillary expansion (RME) protocols. The sample consisted of 20 individuals (nine boys and 11 girls; mean age of 10.4 +/- 2.62 years) with unilateral complete cleft lip and palate who had a constricted maxilla in the vertical and transverse dimensions. Ten patients underwent 1 week of RME with screw activation of one complete turn per day, followed by 23 weeks of maxillary protraction (group 1). The other 10 patients underwent 7 weeks of alternate rapid maxillary expansion and constriction, with one complete turn per day, followed by 17 weeks of maxillary protraction (group 2); both groups underwent a total of 6 months of treatment. Cephalometric measurements were taken at different times: pretreatment (T1), soon after RME (T2), and after 6 months of treatment (T3). Each measurement was analyzed with mixed models for repeated measures, and the covariance structure chosen was compound symmetry. The maxilla displaced slightly forward and downward with a counterclockwise rotation; the mandible rotated downward and backward, resulting in an increase in anterior facial height; the sagittal maxillomandibular relationship was improved; the maxillary molars and incisors were protruded and extruded; and the mandibular incisors were retroclined. There was no significant difference between the groups in evaluation time.

  9. Model of oronasal rehabilitation in children with obstructive sleep apnea syndrome undergoing rapid maxillary expansion: Research review

    Directory of Open Access Journals (Sweden)

    Luca Levrini

    2014-12-01

    Full Text Available Rapid maxillary expansion (RME is a widely used practice in orthodontics. Scientific evidence shows that RME can be helpful in modifying the breathing pattern in mouth-breathing patients. In order to promote the restoration of physiological breathing we have developed a rehabilitation program associated with RME in children. The aim of the study was a literature review and a model of orofacial rehabilitation in children with obstructive sleep apnea undergoing treatment with rapid maxillary expansion. Muscular training (local exercises and general ones is the key factor of the program. It also includes hygienic and behavior instructions as well as other therapeutic procedures such as rhinosinusal washes, a postural re-education (Alexander technique and, if necessary, a pharmacological treatment aimed to improve nasal obstruction. The program should be customized for each patient. If RME is supported by an adequate functional rehabilitation, the possibility to change the breathing pattern is considerably amplified. Awareness, motivation and collaboration of the child and their parents, as well as the cooperation among specialists, such as orthodontist, speech therapist, pediatrician and otolaryngologist, are necessary conditions to achieve the goal.

  10. The impact of urban land expansion on soil quality in rapidly urbanizing regions in China: Kunshan as a case study.

    Science.gov (United States)

    Zhang, Jian; Pu, Lijie; Peng, Buzhuo; Gao, Zhonggui

    2011-04-01

    At a stage of rapid economic development and urbanization in China, most cities are faced with serious problems caused by environment deterioration such as pollution, space press, afforestation degradation, and disordering. Kunshan City, one of the most economically vigorous regions in China, has suffered a more prominent conflict between urbanization and environmental safety. In this paper, urban land expansion in Kunshan City in the Yangtze River Delta was measured with reference to the Landsat data recorded in 1982, 1991, 1995, and 2003 and change in land-use pattern in 1981, 1991, 1995, and 2004 as well as that in nutrients in soils of different purposes between the periods were analyzed to study the effect of urban land-use expansion on soil characteristics. To get a better understanding of soil nutrients, heavy metal content, and pollution, on-the-spot investigation, sampling and laboratory analysis were all conducted, and the geo-accumulation factors and revised Nemerow comprehensive index method were adopted for evaluation of the findings. The results show that the content of organic matter, total nitrogen, rapidly available nitrogen, and available phosphorus in the soil (except available potassium) all increased, and the average content of As, Cd, Cr, Cu, Pb, Ni, Hg, Se, and Zn prove to be 8.61, 0.12, 83.53, 32.49, 29.93, 30.45, 0.27, 0.24, and 93.3 mg kg(-1), respectively, showing degradation in soil quality.

  11. Evaluation of surgically assisted rapid maxillary expansion with piezosurgery versus oscillating saw and chisel osteotomy - a randomized prospective trial

    Science.gov (United States)

    2013-01-01

    Background Ultrasonic bone-cutting surgery has been introduced as a feasible alternative to the conventional sharp instruments used in craniomaxillofacial surgery because of its precision and safety. The piezosurgery medical device allows the efficient cutting of mineralized tissues with minimal trauma to soft tissues. Piezoelectric osteotome has found its role in surgically assisted rapid maxillary expansion (SARME), a procedure well established to correct transverse maxillary discrepancies. The advantages include minimal risk to critical anatomic structures. The purpose of this clinical comparative study (CIS 2007-237-M) was to present the advantages of the piezoelectric cut as a minimally invasive device in surgically assisted, rapid maxillary expansion by protecting the maxillary sinus mucosal lining. Methods Thirty patients (18 females and 12 males) at the age of 18 to 54 underwent a surgically assisted palatal expansion of the maxilla with a combined orthodontic and surgical approach. The patients were randomly divided into two separate treatment groups. While Group 1 received conventional surgery using an oscillating saw, Group 2 was treated with piezosurgery. The following parameters were examined: blood pressure, blood values, required medication, bleeding level in the maxillary sinus, duration of inpatient stay, duration of surgery and height of body temperature. Results The results displayed no statistically significant differences between the two groups regarding laboratory blood values and inpatient stay. The duration of surgery revealed a significant discrepancy. Deploying piezosurgery took the surgeon an average of 10 minutes longer than working with a conventional-saw technique. However, the observation of the bleeding level in the paranasal sinus presented a major and statistically significant advantage of piezosurgery: on average the bleeding level was one category above the one of the remaining patients. Conclusion This method of piezoelectric

  12. Cryptic population dynamics: rapid evolution masks trophic interactions.

    Science.gov (United States)

    Yoshida, Takehito; Ellner, Stephen P; Jones, Laura E; Bohannan, Brendan J M; Lenski, Richard E; Hairston, Nelson G

    2007-09-01

    Trophic relationships, such as those between predator and prey or between pathogen and host, are key interactions linking species in ecological food webs. The structure of these links and their strengths have major consequences for the dynamics and stability of food webs. The existence and strength of particular trophic links has often been assessed using observational data on changes in species abundance through time. Here we show that very strong links can be completely missed by these kinds of analyses when changes in population abundance are accompanied by contemporaneous rapid evolution in the prey or host species. Experimental observations, in rotifer-alga and phage-bacteria chemostats, show that the predator or pathogen can exhibit large-amplitude cycles while the abundance of the prey or host remains essentially constant. We know that the species are tightly linked in these experimental microcosms, but without this knowledge, we would infer from observed patterns in abundance that the species are weakly or not at all linked. Mathematical modeling shows that this kind of cryptic dynamics occurs when there is rapid prey or host evolution for traits conferring defense against attack, and the cost of defense (in terms of tradeoffs with other fitness components) is low. Several predictions of the theory that we developed to explain the rotifer-alga experiments are confirmed in the phage-bacteria experiments, where bacterial evolution could be tracked. Modeling suggests that rapid evolution may also confound experimental approaches to measuring interaction strength, but it identifies certain experimental designs as being more robust against potential confounding by rapid evolution.

  13. Cryptic population dynamics: rapid evolution masks trophic interactions.

    Directory of Open Access Journals (Sweden)

    Takehito Yoshida

    2007-09-01

    Full Text Available Trophic relationships, such as those between predator and prey or between pathogen and host, are key interactions linking species in ecological food webs. The structure of these links and their strengths have major consequences for the dynamics and stability of food webs. The existence and strength of particular trophic links has often been assessed using observational data on changes in species abundance through time. Here we show that very strong links can be completely missed by these kinds of analyses when changes in population abundance are accompanied by contemporaneous rapid evolution in the prey or host species. Experimental observations, in rotifer-alga and phage-bacteria chemostats, show that the predator or pathogen can exhibit large-amplitude cycles while the abundance of the prey or host remains essentially constant. We know that the species are tightly linked in these experimental microcosms, but without this knowledge, we would infer from observed patterns in abundance that the species are weakly or not at all linked. Mathematical modeling shows that this kind of cryptic dynamics occurs when there is rapid prey or host evolution for traits conferring defense against attack, and the cost of defense (in terms of tradeoffs with other fitness components is low. Several predictions of the theory that we developed to explain the rotifer-alga experiments are confirmed in the phage-bacteria experiments, where bacterial evolution could be tracked. Modeling suggests that rapid evolution may also confound experimental approaches to measuring interaction strength, but it identifies certain experimental designs as being more robust against potential confounding by rapid evolution.

  14. Population coding in area V4 during rapid shape detections

    Science.gov (United States)

    Weiner, Katherine F.

    2015-01-01

    While previous studies have suggested that neuronal correlations are common in visual cortex over a range of timescales, the effect of correlations on rapid visually based decisions has received little attention. We trained Macaca mulatta to saccade to a peripherally presented shape embedded in dynamic noise as soon as the shape appeared. While the monkeys performed the task, we recorded from neuronal populations (5–29 cells) using a microelectrode array implanted in area V4, a visual area thought to be involved in form perception. While modest correlations were present between cells during visual stimulation, their magnitude did not change significantly subsequent to the appearance of a shape. We quantified the reliability and temporal precision with which neuronal populations signaled the appearance of the shape and predicted the animals' choices using mutual information analyses. To study the impact of correlations, we shuffled the activity from each cell across observations while retaining stimulus-dependent modulations in firing rate. We found that removing correlations by shuffling across trials minimally affected the reliability or timing with which pairs, or larger groups of cells, signaled the presence of a shape. To assess the downstream impact of correlations, we also studied how shuffling affected the ability of V4 populations to predict behavioral choices. Surprisingly, shuffling created a modest increase in the accuracy of such predictions, suggesting that the reliability of downstream neurons is slightly compromised by activity correlations. Our findings are consistent with neuronal correlations having a minimal effect on the reliability and timing of rapid perceptual decisions. PMID:25787961

  15. Population expansions shared among coexisting bacterial lineages are revealed by genetic evidence.

    Science.gov (United States)

    Avitia, Morena; Escalante, Ana E; Rebollar, Eria A; Moreno-Letelier, Alejandra; Eguiarte, Luis E; Souza, Valeria

    2014-01-01

    Comparative population studies can help elucidate the influence of historical events upon current patterns of biodiversity among taxa that coexist in a given geographic area. In particular, comparative assessments derived from population genetics and coalescent theory have been used to investigate population dynamics of bacterial pathogens in order to understand disease epidemics. In contrast, and despite the ecological relevance of non-host associated and naturally occurring bacteria, there is little understanding of the processes determining their diversity. Here we analyzed the patterns of genetic diversity in coexisting populations of three genera of bacteria (Bacillus, Exiguobacterium, and Pseudomonas) that are abundant in the aquatic systems of the Cuatro Cienegas Basin, Mexico. We tested the hypothesis that a common habitat leaves a signature upon the genetic variation present in bacterial populations, independent of phylogenetic relationships. We used multilocus markers to assess genetic diversity and (1) performed comparative phylogenetic analyses, (2) described the genetic structure of bacterial populations, (3) calculated descriptive parameters of genetic diversity, (4) performed neutrality tests, and (5) conducted coalescent-based historical reconstructions. Our results show a trend of synchronic expansions across most populations independent of both lineage and sampling site. Thus, we provide empirical evidence supporting the analysis of coexisting bacterial lineages in natural environments to advance our understanding of bacterial evolution beyond medical or health-related microbes.

  16. Impact of Spring Bird Migration on the Range Expansion of Ixodes scapularis Tick Population.

    Science.gov (United States)

    Wu, Xiaotian; Röst, Gergely; Zou, Xingfu

    2016-01-01

    Many observational studies suggest that seasonal migratory birds play an important role in spreading Ixodes scapularis, a vector of Lyme disease, along their migratory flyways, and they are believed to be responsible for geographic range expansion of I. scapularis in Canada. However, the interplay between the dynamics of I. scapularis on land and migratory birds in the air is not well understood. In this study, we develop a periodic delay meta-population model which takes into consideration the local landscape for tick reproduction within patches and the times needed for ticks to be transported by birds between patches. Assuming that the tick population is endemic in the source region, we find that bird migration may boost an already established tick population at the subsequent region and thus increase the risk to humans, or bird migration may help ticks to establish in a region where the local landscape is not appropriate for ticks to survive in the absence of bird migration, imposing risks to public health. This theoretical study reveals that bird migration plays an important role in the geographic range expansion of I. scapularis, and therefore our findings may suggest some strategies for Lyme disease prevention and control.

  17. Microcarrier-based expansion of adult murine side population stem cells.

    Directory of Open Access Journals (Sweden)

    Christina A Pacak

    Full Text Available The lack of reliable methods to efficiently isolate and propagate stem cell populations is a significant obstacle to the advancement of cell-based therapies for human diseases. One isolation technique is based on efflux of the fluorophore Hoechst 33342. Using fluorescence-activated cell sorting (FACS, a sub-population containing adult stem cells has been identified in a multitude of tissues in every mammalian species examined. These rare cells are referred to as the 'side population' or SP due to a distinctive FACS profile that results from weak staining by Hoechst dye. Although the SP contains multi-potent cells capable of differentiating toward hematopoietic and mesenchymal lineages; there is currently no method to efficiently expand them. Here, we describe a spinner-flask culture system containing C2C12 myoblasts attached to spherical microcarriers that act to support the growth of non-adherent, post-natal murine skeletal muscle and bone marrow SP cells. Using FACS and hemocytometry, we show expansion of unfractionated EGFP⁺ SP cells over 6 wks. A significant number of these cells retain characteristics of freshly-isolated, unfractionated SP cells with respect to protein expression and dye efflux capacity. Expansion of the SP will permit further study of these heterogeneous cells and determine their therapeutic potential for regenerative and reparative therapies.

  18. Effects of rapid palatal expansion on the sagittal and vertical dimensions of the maxilla: a study on cephalograms derived from cone-beam computed tomography.

    Science.gov (United States)

    Habeeb, Miriam; Boucher, Normand; Chung, Chun-Hsi

    2013-09-01

    The purpose of this study was to use cone-beam computed tomography imaging to examine the skeletal and dental changes in the sagittal and vertical dimensions after rapid palatal expansion. Twenty-eight healthy children (mean age, 9.9 years; range, 7.8-12.8 years; 17 boys, 11 girls) who required rapid palatal expansion treatment were included. For each patient, a bonded Haas-type expander with full occlusal and palatal acrylic coverage was cemented in place. Cone-beam computed tomography images were obtained as part of the pretreatment orthodontic records and at the completion of rapid palatal expansion for all patients. The mean interval between pretreatment and completion of rapid palatal expansion was 52 days (range, 19-96 days). The average skeletal age of the patients, determined from hand-wrist films also obtained before treatment, was 10.1 years. The mean expansion of the expander was 8.0 mm (range, 5.9-9.6 mm). Each cone-beam computed tomography image was compressed from the outer portion of the right side of the patient's head to the center of the left central incisor into a 2-dimensional synthesized cephalogram, which was then traced and measured. The results showed that from pretreatment to completion of rapid palatal expansion, SNA, FH-NA, and A-Nperp increased by means of 1.04°, 0.92°, and 0.87 mm, respectively (P expansion treatment. Bonded rapid palatal expansion treatment resulted in downward displacement of the maxilla with a greater displacement of ANS than PNS and posterior movement of the maxillary central incisors. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  19. Population Genetic Structure and Evidence of Demographic Expansion of the Ayu (Plecoglossus altivelis in East Asia

    Directory of Open Access Journals (Sweden)

    Ye-Seul Kwan

    2012-10-01

    Full Text Available Plecoglossus altivelis (ayu is an amphidromous fish widely distributed in Northeastern Asia from the East China Sea to the northern Japanese coastal waters, encompassing the Korean Peninsula within its range. The shore lines of northeastern region in Asia have severely fluctuated following glaciations in the Quaternary. In the present study, we investigate the population genetic structure and historical demographic change of P. altivelis at a population level in East Asia. Analysis of molecular variance (AMOVA based on 244 mitochondrial control region DNA sequences clearly showed that as the sampling scope extended to a larger geographic area, genetic differentiation began to become significant, particularly among Northeastern populations. A series of hierarchical AMOVA could detect the genetic relationship of three closely located islands between Korea and Japan that might have been tightly connected by the regional Tsushima current. Neutrality and mismatch distribution analyses revealed a strong signature of a recent population expansion of P. altivelis in East Asia, estimated at 126 to 391 thousand years ago during the late Pleistocene. Therefore it suggests that the present population of P. altivelis traces back to its approximate demographic change long before the last glacial maximum. This contrasts our a priori expectation that the most recent glacial event might have the most crucial effect on the present day demography of marine organisms through bottleneck and subsequent increase of effective population size in this region.

  20. Poor man’s 1000 genome project: Recent human population expansion confounds the detection of disease alleles in 7,098 complete mitochondrial genomes

    Directory of Open Access Journals (Sweden)

    Hie Lim eKim

    2013-02-01

    Full Text Available Rapid growth of the human population has caused the accumulation of rare genetic variants that may play a role in the origin of genetic diseases. However, it is challenging to identify those rare variants responsible for specific diseases without genetic data from an extraordinarily large population sample. Here we focused on the accumulated data from the human mitochondrial (mt genome sequences because this data provided 7,098 whole genomes for analysis. In this dataset we identified 6,110 single nucleotide variants (SNVs and their frequency and determined that the best-fit demographic model for the 7,098 genomes included severe population bottlenecks and exponential expansions of the non-African population. Using this model, we simulated the evolution of mt genomes in order to ascertain the behavior of deleterious mutations. We found that such deleterious mutations barely survived during population expansion. We derived the threshold frequency of a deleterious mutation in separate African, Asian, and European populations and used it to identify pathogenic mutations in our dataset. Although threshold frequency was very low, the proportion of variants showing a lower frequency than that threshold was 82%, 83%, and 91% of the total variants for the African, Asian, and European populations, respectively. Within these variants, only 18 known pathogenic mutations were detected in the 7,098 genomes. This result showed the difficulty of detecting a pathogenic mutation within an abundance of rare variants in the human population, even with a large number of genomes available for study.

  1. Population expansion and individual age affect endoparasite richness and diversity in a recolonising large carnivore population

    Science.gov (United States)

    Lesniak, Ines; Heckmann, Ilja; Heitlinger, Emanuel; Szentiks, Claudia A.; Nowak, Carsten; Harms, Verena; Jarausch, Anne; Reinhardt, Ilka; Kluth, Gesa; Hofer, Heribert; Krone, Oliver

    2017-01-01

    The recent recolonisation of the Central European lowland (CEL) by the grey wolf (Canis lupus) provides an excellent opportunity to study the effect of founder events on endoparasite diversity. Which role do prey and predator populations play in the re-establishment of endoparasite life cycles? Which intrinsic and extrinsic factors control individual endoparasite diversity in an expanding host population? In 53 individually known CEL wolves sampled in Germany, we revealed a community of four cestode, eight nematode, one trematode and 12 potential Sarcocystis species through molecular genetic techniques. Infections with zoonotic Echinococcus multilocularis, Trichinella britovi and T. spiralis occurred as single cases. Per capita endoparasite species richness and diversity significantly increased with population size and changed with age, whereas sex, microsatellite heterozygosity, and geographic origin had no effect. Tapeworm abundance (Taenia spp.) was significantly higher in immigrants than natives. Metacestode prevalence was slightly higher in ungulates from wolf territories than from control areas elsewhere. Even though alternative canid definitive hosts might also play a role within the investigated parasite life cycles, our findings indicate that (1) immigrated wolves increase parasite diversity in German packs, and (2) prevalence of wolf-associated parasites had declined during wolf absence and has now risen during recolonisation.

  2. Genetic diversity of two Neolithic populations provides evidence of farming expansions in North China.

    Science.gov (United States)

    Zhang, Ye; Li, Jiawei; Zhao, Yongbin; Wu, Xiyan; Li, Hongjie; Yao, Lu; Zhu, Hong; Zhou, Hui

    2017-02-01

    The West Liao River Valley and the Yellow River Valley are recognized Neolithic farming centers in North China. The population dynamics between these two centers have significantly contributed to the present-day genetic patterns and the agricultural advances of North China. To understand the Neolithic farming expansions between the West Liao River Valley and the Yellow River Valley, we analyzed mitochondrial DNA (mtDNA) and the Y chromosome of 48 individuals from two archeological sites, Jiangjialiang (>3000 BC) and Sanguan (~1500 BC). These two sites are situated between the two farming centers and experienced a subsistence shift from hunting to farming. We did not find a significant difference in the mtDNA, but their genetic variations in the Y chromosome were different. Individuals from the Jiangjialiang belonged to two Y haplogroups, N1 (not N1a or N1c) and N1c. The individuals from the Sanguan are Y haplogroup O3. Two stages of migration are supported. Populations from the West Liao River Valley spread south at about 3000 BC, and a second northward expansion from the Yellow River Valley occurred later (3000-1500 BC).

  3. Long-term stability of combined rapid palatal expansion-lip bumper therapy followed by full fixed appliances.

    Science.gov (United States)

    Ferris, Tyler; Alexander, R G; Boley, Jimmy; Buschang, Peter H

    2005-09-01

    The purpose of this study was to evaluate the long-term postretention stability of rapid palatal expansion-lip bumper therapy followed by full fixed appliances. The sample included 20 treated patients (11 women and 9 men) who were recalled to obtain postretention records. The subjects were out of retention for a minimum of 4 years and an average of 7.9 years. They had begun treatment in the late mixed dentition at a mean age of 11.1 with considerable incisor crowding but, on average, no tooth size-arch length discrepancies. Pretreatment, posttreatment (mean age, 13.6 years), and postretention (mean age, 24.3 years) models were digitized, and the computed measurements were compared with untreated reference data. The majority of treatment increases in maxillary and mandibular arch dimensions were statistically significant (P lip bumper expansion therapy in the late mixed dentition followed by full fixed appliances is an effective form of treatment for patients with up to moderate tooth size-arch length discrepancies.

  4. Changes in skeletal and dental relationship in Class II Division I malocclusion after rapid maxillary expansion: a prospective study.

    Science.gov (United States)

    Baratieri, Carolina; Alves, Matheus; Bolognese, Ana Maria; Nojima, Matilde C G; Nojima, Lincoln I

    2014-01-01

    To assess skeletal and dental changes immediately after rapid maxillary expansion (RME) in Class II Division 1 malocclusion patients and after a retention period, using cone beam computed tomography (CBCT) imaging. Seventeen children with Class II, Division 1 malocclusion and maxillary skeletal transverse deficiency underwent RME following the Haas protocol. CBCT were taken before treatment (T1), at the end of the active expansion phase (T2) and after a retention period of 6 months (T3). The scanned images were measured anteroposteriorly (SNA, SNB, ANB, overjet and MR) and vertically (N-ANS, ANS-Me, N-Me and overbite). Significant differences were identified immediately after RME as the maxilla moved forward, the mandible moved downward, overjet increased and overbite decreased. During the retention period, the maxilla relapsed backwards and the mandible was displaced forward, leaving patients with an overall increase in anterior facial height. RME treatment allowed more anterior than inferior positioning of the mandible during the retention period, thus significantly improving Class II dental relationship in 75% of the patients evaluated.

  5. Changes in skeletal and dental relationship in Class II Division I malocclusion after rapid maxillary expansion: a prospective study

    Directory of Open Access Journals (Sweden)

    Carolina Baratieri

    2014-06-01

    Full Text Available OBJECTIVE: To assess skeletal and dental changes immediately after rapid maxillary expansion (RME in Class II Division 1 malocclusion patients and after a retention period, using cone beam computed tomography (CBCT imaging. METHODS: Seventeen children with Class II, Division 1 malocclusion and maxillary skeletal transverse deficiency underwent RME following the Haas protocol. CBCT were taken before treatment (T1, at the end of the active expansion phase (T2 and after a retention period of 6 months (T3. The scanned images were measured anteroposteriorly (SNA, SNB, ANB, overjet and MR and vertically (N-ANS, ANS-Me, N-Me and overbite. RESULTS: Significant differences were identified immediately after RME as the maxilla moved forward, the mandible moved downward, overjet increased and overbite decreased. During the retention period, the maxilla relapsed backwards and the mandible was displaced forward, leaving patients with an overall increase in anterior facial height. CONCLUSION: RME treatment allowed more anterior than inferior positioning of the mandible during the retention period, thus significantly improving Class II dental relationship in 75% of the patients evaluated.

  6. Rapid wetland expansion during European settlement and its implication for marsh survival under modern sediment delivery rates

    Science.gov (United States)

    Kirwan, Matthew L.; Murray, A. Brad; Donnelly, Jeffrey P.; Corbett, D. Reide

    2011-01-01

    Fluctuations in sea-level rise rates are thought to dominate the formation and evolution of coastal wetlands. Here we demonstrate a contrasting scenario in which land-use-related changes in sediment delivery rates drive the formation of expansive marshland, and vegetation feedbacks maintain their morphology despite recent sediment supply reduction. Stratigraphic analysis and radiocarbon dating in the Plum Island Estuary (Massachusetts, United States) suggest that salt marshes expanded rapidly during the eighteenth and nineteenth centuries due to increased rates of sediment delivery following deforestation associated with European settlement. Numerical modeling coupled with the stratigraphic observations suggests that existing marshland could survive, but not form under the low suspended sediment concentrations observed in the estuary today. These results suggest that many of the expansive marshes that characterize the modern North American coast are metastable relicts of high nineteenth century sediment delivery rates, and that recent observations of degradation may represent a slow return to pre-settlement marsh extent. In contrast to ecosystem management practices in which restoring pre-anthropogenic conditions is seen as a way to increase ecosystem services, our results suggest that widespread efforts to restore valuable coastal wetlands actually prevent some systems from returning to a natural state.

  7. Rapid palatal expansion effects on mandibular transverse dimensions in unilateral posterior crossbite patients: a three-dimensional digital imaging study

    Directory of Open Access Journals (Sweden)

    Alessandro Ugolini

    2016-01-01

    Full Text Available Abstract Background The purpose of this controlled study was to investigate indirect effects on mandibular arch dimensions, 1 year after rapid palatal expansion (RPE therapy. Methods Thirty-three patients in mixed dentition (mean age 8.8 years showing unilateral posterior crossbite and maxillary deficiency were treated with a RPE (Haas type cemented on the first permanent molars. Treatment protocol consisted of two turns per day until slight overcorrection of the molar transverse relationship occurred. The Haas expander was kept on the teeth as a passive retainer for an average of 6 months. Study models were taken prior (T1 and 15 months on average (T2 after expansion. A control group of 15 untreated subjects with maxillary deficiency (mean age 8.3 years was also recorded with a 12-month interval. Stone casts were digitized with a 3D scanner (3Shape, DK. Results In the treated group, both mandibular intermolar distance (+1.9 mm and mandibular molar angulation (+9° increased. Mandibular incisor angulation showed an increase of 1.9°. There was little effect on intercanine distance and canine angulation. Controls showed a reduction in transverse arch dimension and a decrease in molar and canine angulation values. Conclusions RPE protocol has indirect widening effects on the mandibular incisors and first molars.

  8. The Rapid Analysis of Scattering from Periodic Dielectric Structures Using Accelerated Cartesian Expansions (ACE)

    CERN Document Server

    Baczewski, Andrew D; Shanker, Balasubramaniam

    2011-01-01

    The analysis of fields in periodic dielectric structures arise in numerous applications of recent interest, ranging from photonic bandgap (PBG) structures and plasmonically active nanostructures to metamaterials. To achieve an accurate representation of the fields in these structures using numerical methods, dense spatial discretization is required. This, in turn, affects the cost of analysis, particularly for integral equation based methods, for which traditional iterative methods require O(N^2) operations, N being the number of spatial degrees of freedom. In this paper, we introduce a method for the rapid solution of volumetric electric field integral equations used in the analysis of doubly periodic dielectric structures. The crux of our method is the ACE algorithm, which is used to evaluate the requisite potentials in O(N) cost. Results are provided that corroborate our claims of acceleration without compromising accuracy, as well as the application of our method to a number of compelling photonics applic...

  9. Rapid expansion of the protein disulfide isomerase gene family facilitates the folding of venom peptides

    DEFF Research Database (Denmark)

    Safavi-Hemami, Helena; Li, Qing; Jackson, Ronneshia L.

    2016-01-01

    Formation of correct disulfide bonds in the endoplasmic reticulum is a crucial step for folding proteins destined for secretion. Protein disulfide isomerases (PDIs) play a central role in this process. We report a previously unidentified, hypervariable family of PDIs that represents the most...... diverse gene family of oxidoreductases described in a single genus to date. These enzymes are highly expressed specifically in the venom glands of predatory cone snails, animals that synthesize a remarkably diverse set of cysteine-rich peptide toxins (conotoxins). Enzymes in this PDI family, termed...... conotoxin-specific PDIs, significantly and differentially accelerate the kinetics of disulfide-bond formation of several conotoxins. Our results are consistent with a unique biological scenario associated with protein folding: The diversification of a family of foldases can be correlated with the rapid...

  10. Rabbit antithymocyte globulin induces rapid expansion of effector memory CD8 T cells without accelerating acute graft versus host disease.

    Science.gov (United States)

    Wittenbecher, Friedrich; Rieger, Kathrin; Dziubianau, Mikalai; Herholz, Anne; Mensen, Angela; Blau, Igor Wolfgang; Uharek, Lutz; Dörken, Bernd; Thiel, Andreas; Na, Il-Kang

    2013-01-01

    Rabbit antithymocyte globulin (Thymoglobulin(®)) is commonly used as graft-versus-host disease (GvHD) prophylaxis. Since we found similar total CD8 T cell numbers in patients with and without Thymoglobulin(®) therapy within the first six months after allogeneic hematopoietic stem cell transplantation, we have analyzed the reconstitution of the CD8 T cell compartment in detail. After T cell-depletion, higher and more sustained proliferative capacity of memory CD8 T cells resulted in their rapid expansion, whereas the fraction of naive CD8 T cells decreased. Importantly, this shift towards effector memory CD8 T cells did not accelerate the incidence of GvHD.

  11. Rapid conversions and avoided deforestation: examining four decades of industrial plantation expansion in Borneo

    Science.gov (United States)

    Gaveau, David L. A.; Sheil, Douglas; Husnayaen; Salim, Mohammad A.; Arjasakusuma, Sanjiwana; Ancrenaz, Marc; Pacheco, Pablo; Meijaard, Erik

    2016-09-01

    New plantations can either cause deforestation by replacing natural forests or avoid this by using previously cleared areas. The extent of these two situations is contested in tropical biodiversity hotspots where objective data are limited. Here, we explore delays between deforestation and the establishment of industrial tree plantations on Borneo using satellite imagery. Between 1973 and 2015 an estimated 18.7 Mha of Borneo’s old-growth forest were cleared (14.4 Mha and 4.2 Mha in Indonesian and Malaysian Borneo). Industrial plantations expanded by 9.1 Mha (7.8 Mha oil-palm; 1.3 Mha pulpwood). Approximately 7.0 Mha of the total plantation area in 2015 (9.2 Mha) were old-growth forest in 1973, of which 4.5-4.8 Mha (24-26% of Borneo-wide deforestation) were planted within five years of forest clearance (3.7-3.9 Mha oil-palm; 0.8-0.9 Mha pulpwood). This rapid within-five-year conversion has been greater in Malaysia than in Indonesia (57-60% versus 15-16%). In Indonesia, a higher proportion of oil-palm plantations was developed on already cleared degraded lands (a legacy of recurrent forest fires). However, rapid conversion of Indonesian forests to industrial plantations has increased steeply since 2005. We conclude that plantation industries have been the principle driver of deforestation in Malaysian Borneo over the last four decades. In contrast, their role in deforestation in Indonesian Borneo was less marked, but has been growing recently. We note caveats in interpreting these results and highlight the need for greater accountability in plantation development.

  12. Stress and displacement patterns in the craniofacial skeleton with rapid maxillary expansion-a finite element method study.

    Science.gov (United States)

    Priyadarshini, J; Mahesh, C M; Chandrashekar, B S; Sundara, Abhishek; Arun, A V; Reddy, Vinay P

    2017-12-01

    Rapid maxillary expansion (RME), indicated in the treatment of maxillary deficiency directs high forces to maxillary basal bone and to other adjacent skeletal bones. The aim of this study is to (i) evaluate stress distribution along craniofacial sutures and (ii) study the displacement of various craniofacial structures with rapid maxillary expansion therapy by using a Finite Element model. An analytical model was developed from a dried human skull of a 12 year old male. CT scan images of the skull were taken in axial direction parallel to the F-H plane at 1 mm interval, processed using Mimics software, required portion of the skull was exported into stereo-lithography model. ANSYS software was used to solve the mathematical equation. Contour plots of the displacement and stresses were obtained from the results of the analysis performed. At Node 47005, maximum X-displacement was 5.073 mm corresponding to the incisal edge of the upper central incisor. At Node 3971, maximum negative Y-displacement was -0.86 mm which corresponds to the anterior zygomatic arch, indicating posterior movement of craniofacial complex. At Node 32324, maximum negative Z-displacement was -0.92 mm representing the anterior and deepest convex portion of the nasal septum; indicating downward displacement of structures medial to the area of force application. Pyramidal displacement of maxilla was evident. Apex of pyramid faced the nasal bone and base was located on the oral side. Posterosuperior part of nasal cavity moved minimally in lateral direction and width of nasal cavity at the floor of the nose increased, there was downward and forward movement of maxilla with a tendency toward posterior rotation. Maximum von Mises stresses were found along midpalatal, pterygomaxillary, nasomaxillary and frontomaxillary sutures.

  13. Liquefaction of coals using ultra-fine particle, unsupported catalysts: In situ particle generation by rapid expansion of supercritical fluid solutions. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    1994-05-01

    The research conducted by Textron Defense Systems (TDS) represents a potential new and innovative concept for dispersed coal liquefaction. The technical approach is generation of ultra-fine catalyst particles from supercritical solutions by rapid expansion of either catalyst only, or mixtures of catalyst and coal material in supersaturated solvents. The process of rapid expansion of supercritical fluid solutions was developed at Battelle`s Pacific Northwest Laboratories for the intended purpose of providing a new analytical technique for characterizing supercritical fluids. The concept forming the basis of this research is that ultra-fine particles can be generated from supercritical solutions by rapid expansion of either catalyst or catalyst/coal-material mixtures in supersaturated solvents, such as carbon dioxide or water. The focal point of this technique is the rapid transfer of low vapor pressure solute (i.e., catalyst), dissolved in the supercritical fluid solvent, to the gas phase as the solution is expanded through an orifice. The expansion process is characterized by highly nonequilibrium conditions which cause the solute to undergo extremely rapid supersaturation with respect to the solvent, leading to nucleation and particle growth resulting in nanometer size catalyst particles. A supercritical expansion system was designed and built by TDS at their Haverhill facility.

  14. Short-term evaluation of tegumentary changes of the nose in oral breathers undergoing rapid maxillary expansion.

    Science.gov (United States)

    Badreddine, Fauze Ramez; Fujita, Reginaldo Raimundo; Cappellette, Mario

    2017-06-26

    Rapid maxillary expansion is an orthodontic and orthopedic procedure that can change the form and function of the nose. The soft tissue of the nose and its changes can influence the esthetics and the stability of the results obtained by this procedure. The objective of this study was to assess the changes in nose dimensions after rapid maxillary expansion (RME) in oral breathers with maxillary atresia, using a reliable and reproducible methodology through computed tomography. A total of 30 mouth-breathing patients with maxillary atresia were analyzed and divided into a treatment group who underwent RME (20 patients, 10 of which were male and 10 female, with a MA of 8.9 years and a SD of 2.16, ranging from 6.5 to 12.5 years) and a Control Group (10 patients, 5 of which were male and 5 female, with a MA of 9.2 years, SD of 2.17, ranging from 6.11 to 13.7 years). In the treatment group, multislice computed tomography scans were obtained at the start of the treatment (T1) and 3 months after expansion (T2). The patients of the control group were submitted to the same exams at the same intervals of time. Four variables related to soft tissue structures of the nose were analyzed (alar base width, alar width, height of soft tissue of the nose and length of soft tissue of the nose), and the outcomes between T1 and T2 were compared using Osirix MD software. In the TG, the soft tissues of the nose exhibited significant increases in all variables studied (p0.05). In the treatment group, mean alar base width increased by 4.87% (p=0.004), mean alar width increased by 4.04% (p=0.004), mean height of the soft tissues of the nose increased by 4.84% (p=0.003) and mean length of the soft tissues of the nose increased by 4.29% (p=0.012). In short-term, RME provided a statistically significant increase in the dimensions of the soft tissues of the nose. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All

  15. Global patent landscape of programmed cell death 1: implications of the rapid expansion.

    Science.gov (United States)

    Kong, Xiangjun; Zhang, Qianru; Lai, Yunfeng; Hu, Hao; Chen, Xin; Hu, Yuanjia

    2018-01-01

    Inhibitors of programmed cell death 1 (PD-1) and its ligands are producing a paradigm shift in cancer treatment. The promising clinical outcomes and a multi-billion dollar market have prompted active research and development and resulted in relentless patent protection. However, the global patent landscape in this field remains unclear. Areas covered: The patent landscape encompassing global patenting activities and developing trends in the field is discussed based on a data set of 1287 patent families. Patenting activities have expanded rapidly in the past three years. Specific trends in relevant aspects are presented, including patent filing countries, patent ownership, co-patents, technical areas, and technological connections in terms of patent citation relationships. Expert opinion: Together with patenting momentum in recent years, fragmented ownership and dense technological connections of PD-1-related inventions raise the possibility of a patent thicket. The explosion of patent applications and complex citation relationships could also lead to considerable patent conflicts and disputes on overlapping intellectual property rights, in addition to existing legal uncertainties. Patent applicants in this field are encouraged to be aware of these concerns when developing valid patent strategies.

  16. Topology of evolving, mutagenized viral populations: quasispecies expansion, compression, and operation of negative selection

    Directory of Open Access Journals (Sweden)

    Sierra Saleta

    2008-07-01

    Full Text Available Abstract Background The molecular events and evolutionary forces underlying lethal mutagenesis of virus (or virus extinction through an excess of mutations are not well understood. Here we apply for the first time phylogenetic methods and Partition Analysis of Quasispecies (PAQ to monitor genetic distances and intra-population structures of mutant spectra of foot-and-mouth disease virus (FMDV quasispecies subjected to mutagenesis by base and nucleoside analogues. Results Phylogenetic and PAQ analyses have revealed a highly dynamic variation of intrapopulation diversity of FMDV quasispecies. The population diversity first suffers striking expansions in the presence of mutagens and then compressions either when the presence of the mutagenic analogue was discontinued or when a mutation that decreased sensitivity to a mutagen was selected. The pattern of mutations found in the populations was in agreement with the behavior of the corresponding nucleotide analogues with FMDV in vitro. Mutations accumulated at preferred genomic sites, and dn/ds ratios indicate the operation of negative (or purifying selection in populations subjected to mutagenesis. No evidence of unusually elevated genetic distances has been obtained for FMDV populations approaching extinction. Conclusion Phylogenetic and PAQ analysis provide adequate procedures to describe the evolution of viral sequences subjected to lethal mutagenesis. These methods define the changes of intra-population structure more precisely than mutation frequencies and Shannon entropies. PAQ is very sensitive to variations of intrapopulation genetic distances. Strong negative (or purifying selection operates in FMDV populations subjected to enhanced mutagenesis. The quantifications provide evidence that extinction does not imply unusual increases of intrapopulation complexity, in support of the lethal defection model of virus extinction.

  17. Comparative phylogeography of a coevolved community: concerted population expansions in Joshua trees and four yucca moths

    Science.gov (United States)

    Smith, Christopher Irwin; Tank, Shantel; Godsoe, William; Levenick, Jim; Strand, Eva; Esque, Todd C.; Pellmyr, Olle

    2011-01-01

    Comparative phylogeographic studies have had mixed success in identifying common phylogeographic patterns among co-distributed organisms. Whereas some have found broadly similar patterns across a diverse array of taxa, others have found that the histories of different species are more idiosyncratic than congruent. The variation in the results of comparative phylogeographic studies could indicate that the extent to which sympatrically-distributed organisms share common biogeographic histories varies depending on the strength and specificity of ecological interactions between them. To test this hypothesis, we examined demographic and phylogeographic patterns in a highly specialized, coevolved community – Joshua trees (Yucca brevifolia) and their associated yucca moths. This tightly-integrated, mutually interdependent community is known to have experienced significant range changes at the end of the last glacial period, so there is a strong a priori expectation that these organisms will show common signatures of demographic and distributional changes over time. Using a database of >5000 GPS records for Joshua trees, and multi-locus DNA sequence data from the Joshua tree and four species of yucca moth, we combined paleaodistribution modeling with coalescent-based analyses of demographic and phylgeographic history. We extensively evaluated the power of our methods to infer past population size and distributional changes by evaluating the effect of different inference procedures on our results, comparing our palaeodistribution models to Pleistocene-aged packrat midden records, and simulating DNA sequence data under a variety of alternative demographic histories. Together the results indicate that these organisms have shared a common history of population expansion, and that these expansions were broadly coincident in time. However, contrary to our expectations, none of our analyses indicated significant range or population size reductions at the end of the last glacial

  18. Controlled auto-ignition characteristics of methane-air mixture in a rapid intake compression and expansion machine

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Gyubaek; Jeong, Dongsoo [Engine Research Team, Eco-Machinery Research Division, Korea Institute of Machinery and Materials, 104 Sinseongno, Yuseong-gu, Daejeon 305-701 (Korea); Moon, Gunfeel [Department of Clean Environmental system, University of Science and Technology, 52 Eoeun-dong, Yuseong-gu, Daejeon (Korea); Bae, Choongsik [Engine Laboratory, Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, 373-1 GuSeong-Dong, Yuseong-Gu, Daejeon 305-701 (Korea)

    2010-10-15

    The characteristics of controlled auto-ignition (CAI) were investigated with a methane-air mixture and simulated residual gas, that represents internal exhaust gas recirculation (IEGR). Supply systems were additionally installed on the conventional rapid compression machine (RCM), and this modified machine - a rapid intake compression and expansion machine (RICEM) - was able to simulate an intake stroke for the evaluation of controlled auto-ignition with fuel-air mixture. The fuel-air mixture and the simulated residual gas were introduced separately into the combustion chamber through the spool valves. Various IEGR rates and temperatures of the IEGR gas were tested. The initial reaction and the development in controlled auto-ignition combustion were compared with spark-ignited combustion by visualization with a high-speed digital camera. Under the controlled auto-ignition operation, multi-point ignition and faster combustion were observed. With increasing the temperature of IEGR gas, the auto-ignition timing was advanced and burning duration was shortened. The higher rate of IEGR had the same effects on the combustion of the controlled auto-ignition. However, this trend was reversed with more than 47 per cent of IEGR. (author)

  19. Urban Land Expansion and Sustainable Land Use Policy in Shenzhen: A Case Study of China’s Rapid Urbanization

    Directory of Open Access Journals (Sweden)

    Jing Qian

    2015-12-01

    Full Text Available Shenzhen is a city that is highly representative of China’s rapid urbanization process. As the city rapidly expands, there are enormous challenges to the sustainable use of land resources. This paper introduces the evolution of urban land expansion and the sustainable land use policy of the Shenzhen Government since 2005. The policy covers the reduction in rural-to-urban land conversion, the delineation of urban growth boundaries, arable land reclamation and the establishment of farmland protection areas, urban redevelopment, and the investigation and prosecution of illegal construction. This paper considers the aspects of urbanization and land management systems that are unique to China. The current top-down indicative and mandatory mode of control, which relies on the central government, has very limited effects. Good results were achieved in Shenzhen for the following elements: governmental self-restraint, governmental identity change, and policy innovation. Shenzhen’s sustainable land use practices can provide a reference for other cities in China.

  20. Mitochondrial DNA Variation and Range Expansion in Western Bean Cutworm (Lepidoptera: Noctuidae): No Evidence for a Recent Population Bottleneck

    Science.gov (United States)

    The western bean cutworm, Striacosta albicosta (Smith) (Lepidoptera: Noctuidae) is a pest of both corn and dry bean crops. At the beginning of the 21st century, the species began to extend its range out of the Great Plains, eastward through the Corn Belt. This rapid range expansion is remarkable bec...

  1. Heterogeneous glacial lake changes and links of lake expansions to the rapid thinning of adjacent glacier termini in the Himalayas

    Science.gov (United States)

    Song, Chunqiao; Sheng, Yongwei; Wang, Jida; Ke, Linghong; Madson, Austin; Nie, Yong

    2017-03-01

    Glacier mass loss in the Himalayas has far-reaching implications for the alteration of regional hydrologic regimes, an increased risk of glacial lake outburst, downstream water resource abundance, and contributions to sea level rise. However, the mass losses of Himalayan glaciers are not well understood towing to the scarcity of observations and the heterogeneous responses of Himalayan glaciers to climate change and local factors (e.g., glacier surge, interacting with proglacial lakes). In particular, there is a lack of understanding on the unique interactions between moraine-dammed glacial lakes and their effects on debris cover on valley glacier termini. In this study, we examined the temporal evolution of 151 large glacial lakes across the Himalayas and then classified these glacial lakes into three categories: proglacial lakes in contact with full or partial debris-covered glaciers (debris-contact lakes), ice cliff-contact lakes, and non-glacier-contact lakes. The results show that debris-contact lakes experienced a dramatic areal increase of 36.5% over the years 2000 to 2014, while the latter two categories of lakes remained generally stable. The majority of lake expansions occurred at the glacier front without marked lake level rises. This suggests that the rapid expansion of these debris-contact lakes can be largely attributed to the thinning of debris-covered ice as caused by the melting of glacial fronts and the subsequent glacial retreat. We reconstructed the height variations of glacier fronts in contact with 57 different proglacial lakes during the years 2000 to 2014. These reconstructed surface elevation changes of debris-covered, lake-contact glacier fronts reveal significant thinning trends with considerable lowering rates that range from 1.0 to 9.7 m/y. Our study reveals that a substantial average ice thinning of 3.9 m/y occurred at the glacier fronts that are in contact with glacial lakes.

  2. A GAA repeat expansion reporter model of Friedreich's ataxia recapitulates the genomic context and allows rapid screening of therapeutic compounds.

    Science.gov (United States)

    Lufino, Michele M P; Silva, Ana M; Németh, Andrea H; Alegre-Abarrategui, Javier; Russell, Angela J; Wade-Martins, Richard

    2013-12-20

    Friedreich's ataxia (FRDA) is caused by large GAA expansions in intron 1 of the frataxin gene (FXN), which lead to reduced FXN expression through a mechanism not fully understood. Understanding such mechanism is essential for the identification of novel therapies for FRDA and this can be accelerated by the development of cell models which recapitulate the genomic context of the FXN locus and allow direct comparison of normal and expanded FXN loci with rapid detection of frataxin levels. Here we describe the development of the first GAA-expanded FXN genomic DNA reporter model of FRDA. We modified BAC vectors carrying the whole FXN genomic DNA locus by inserting the luciferase gene in exon 5a of the FXN gene (pBAC-FXN-Luc) and replacing the six GAA repeats present in the vector with an ∼310 GAA repeat expansion (pBAC-FXN-GAA-Luc). We generated human clonal cell lines carrying the two vectors using site-specific integration to allow direct comparison of normal and expanded FXN loci. We demonstrate that the presence of expanded GAA repeats recapitulates the epigenetic modifications and repression of gene expression seen in FRDA. We applied the GAA-expanded reporter model to the screening of a library of novel small molecules and identified one molecule which up-regulates FXN expression in FRDA patient primary cells and restores normal histone acetylation around the GAA repeats. These results suggest the potential use of genomic reporter cell models for the study of FRDA and the identification of novel therapies, combining physiologically relevant expression with the advantages of quantitative reporter gene expression.

  3. Controlling range expansion in habitat networks by adaptively targeting source populations.

    Science.gov (United States)

    Hock, Karlo; Wolff, Nicholas H; Beeden, Roger; Hoey, Jessica; Condie, Scott A; Anthony, Kenneth R N; Possingham, Hugh P; Mumby, Peter J

    2016-08-01

    Controlling the spread of invasive species, pests, and pathogens is often logistically limited to interventions that target specific locations at specific periods. However, in complex, highly connected systems, such as marine environments connected by ocean currents, populations spread dynamically in both space and time via transient connectivity links. This results in nondeterministic future distributions of species in which local populations emerge dynamically and concurrently over a large area. The challenge, therefore, is to choose intervention locations that will maximize the effectiveness of the control efforts. We propose a novel method to manage dynamic species invasions and outbreaks that identifies the intervention locations most likely to curtail population expansion by selectively targeting local populations most likely to expand their future range. Critically, at any point during the development of the invasion or outbreak, the method identifies the local intervention that maximizes the long-term benefit across the ecosystem by restricting species' potential to spread. In so doing, the method adaptively selects the intervention targets under dynamically changing circumstances. To illustrate the effectiveness of the method we applied it to controlling the spread of crown-of-thorns starfish (Acanthaster sp.) outbreaks across Australia's Great Barrier Reef. Application of our method resulted in an 18-fold relative improvement in management outcomes compared with a random targeting of reefs in putative starfish control scenarios. Although we focused on applying the method to reducing the spread of an unwanted species, it can also be used to facilitate the spread of desirable species through connectivity networks. For example, the method could be used to select those fragments of habitat most likely to rebuild a population if they were sufficiently well protected. © 2016 Society for Conservation Biology.

  4. Detalhes singulares nos procedimentos operacionais da disjunção palatina Singular aspects to operate rapid palatal expansion procedures

    Directory of Open Access Journals (Sweden)

    Orlando Tanaka

    2004-08-01

    Full Text Available A disjunção palatina traz benefícios significativos nas más oclusões caracterizadas pela atresia esquelética do arco dentário superior. Desde os tempos de Angell muitos manuais foram criados com o intuito de orientar a instalação de aparelhos construídos em diferentes formatos e com materiais dos mais diversos fabricantes, utilizando, ainda, diferentes protocolos de ativação que objetivam a referida correção. A tecnologia utilizada para melhorar os materiais componentes dos aparelhos ortodônticos é muito importante mas os pequenos detalhes, que na verdade, não são pequenos, aliados aos conhecimentos científicos e ao bom senso devem ser observados, pois não se deve esperar que o aparelho "faça e resolva" tudo, corrigindo "num passe de mágica" as mordidas cruzadas posteriores. Este trabalho tem por objetivo detalhar as minúcias globais importantes, seja na confecção, na ativação e nos cuidados durante a permanência do disjuntor palatino na cavidade bucal.The rapid maxillary expansion procedure provide significant benefits in malocclusions with esqueletal posterior crossbites.Since Angell, lots of manuals were made in effort to guide the assembly of appliances from different types and employment of several techniques to obtain the desired correction. The technology used to improve the appliance materials is very important, but little details that actually are not so small together with scientific acknowledge and good sense must be regarded because one can not wait for the appliance “to do and solve” everything, correcting the posterior cross bites by a sleight-of-hand trick. The purpose of this report is to detail some little global aspects about construction, activation and concerns during the permanence period of the rapid maxillary expansion appliance in the mouth.

  5. IGF1 stimulates crypt expansion via differential activation of 2 intestinal stem cell populations

    Science.gov (United States)

    Van Landeghem, Laurianne; Santoro, M. Agostina; Mah, Amanda T.; Krebs, Adrienne E.; Dehmer, Jeffrey J.; McNaughton, Kirk K.; Helmrath, Michael A.; Magness, Scott T.; Lund, P. Kay

    2015-01-01

    Insulin-like growth factor 1 (IGF1) has potent trophic effects on normal or injured intestinal epithelium, but specific effects on intestinal stem cells (ISCs) are undefined. We used Sox9-enhanced green fluorescent protein (EGFP) reporter mice that permit analyses of both actively cycling ISCs (Sox9-EGFPLow) and reserve/facultative ISCs (Sox9-EGFPHigh) to study IGF1 action on ISCs in normal intestine or during crypt regeneration after high-dose radiation-induced injury. We hypothesized that IGF1 differentially regulates proliferation and gene expression in actively cycling and reserve/facultative ISCs. IGF1 was delivered for 5 days using subcutaneously implanted mini-pumps in uninjured mice or after 14 Gy abdominal radiation. ISC numbers, proliferation, and transcriptome were assessed. IGF1 increased epithelial growth in nonirradiated mice and enhanced crypt regeneration after radiation. In uninjured and regenerating intestines, IGF1 increased total numbers of Sox9-EGFPLow ISCs and percentage of these cells in M-phase. IGF1 increased percentages of Sox9-EGFPHigh ISCs in S-phase but did not expand this population. Microarray revealed that IGF1 activated distinct gene expression signatures in the 2 Sox9-EGFP ISC populations. In vitro IGF1 enhanced enteroid formation by Sox9-EGFPHigh facultative ISCs but not Sox9-EGFPLow actively cycling ISCs. Our data provide new evidence that IGF1 activates 2 ISC populations via distinct regulatory pathways to promote growth of normal intestinal epithelium and crypt regeneration after irradiation.—Van Landeghem, L., Santoro, M. A., Mah, A. T., Krebs, A. E., Dehmer, J. J., McNaughton, K. K., Helmrath, M. A., Magness, S. T., Lund, P. K. IGF1 stimulates crypt expansion via differential activation of 2 intestinal stem cell populations. PMID:25837582

  6. Rapid expansion of recycling stem cells in cultures of plastic-adherent cells from human bone marrow

    Science.gov (United States)

    Colter, David C.; Class, Reiner; DiGirolamo, Carla M.; Prockop, Darwin J.

    2000-01-01

    Cultures of plastic-adherent cells from bone marrow have attracted interest because of their ability to support growth of hematopoietic stem cells, their multipotentiality for differentiation, and their possible use for cell and gene therapy. Here we found that the cells grew most rapidly when they were initially plated at low densities (1.5 or 3.0 cells/cm2) to generate single-cell derived colonies. The cultures displayed a lag phase of about 5 days, a log phase of rapid growth of about 5 days, and then a stationary phase. FACS analysis demonstrated that stationary cultures contained a major population of large and moderately granular cells and a minor population of small and agranular cells here referred to as recycling stem cells or RS-1 cells. During the lag phase, the RS-1 cells gave rise to a new population of small and densely granular cells (RS-2 cells). During the late log phase, the RS-2 cells decreased in number and regenerated the pool of RS-1 cells found in stationary cultures. In repeated passages in which the cells were plated at low density, they were amplified about 109-fold in 6 wk. The cells retained their ability to generate single-cell derived colonies and therefore apparently retained their multipotentiality for differentiation. PMID:10725391

  7. Cephalometric evaluation of the hyoid triangle before and after maxillary rapid expansion in patients with skeletal class II, mixed dentition, and infantile swallowing.

    Science.gov (United States)

    Parisella, Valeria; Vozza, Iole; Capasso, Francesca; Luzzi, Valeria; Ierardo, Gaetano; Nofroni, Italo; Polimeni, Antonella

    2012-07-01

    Rocabado's hyoid triangle is the only cephalometric parameter that can assess the effects of orthodontic treatment on tongue posture. To evaluate the restoration of tongue posture and function by conducting a cephalometric assessment of the hyoid triangle before and after rapid maxillary expansion. Sixty-four healthy patients aged 6-11 years with skeletal class II malocclusion, mixed dentition, and infantile swallowing took part in this study. They submitted to lateral cephalometric radiography before and after orthodontic maxillary rapid expansion, in order to assess the resulting changes in the proportions of the hyoid triangle (following Rocabado's parameters). The cephalometric findings were compared according to sex, age, and divergence using the chi-square McNemar test at the 5% significance level (ptriangle was modified by the orthodontic maxillary expansion, reconditioning of tongue posture and function particularly among male, aged 6-7 years old with skeletal class II malocclusion, mixed dentition, and infantile swallowing.

  8. [Effect of maxillary protraction with or without rapid palatal expansion in treating early skeletal Class III malocclusion].

    Science.gov (United States)

    Ma, Wen-Sheng; Lu, Hai-Yan; Dong, Fu-Sheng; Hu, Xiao-Ying; Li, Xing-Chao

    2009-04-01

    To evaluate the effectiveness of treatment with maxillary protraction with or without rapid palatal expansion (RPE) for skeletal Class III malocclusion in mixed dentition. A total of 31 children with Class III malocclusion in mixed dentition were selected, and 15 (group A) received maxillary protraction treatment with RPE, the other 16 (group B) received maxillary protraction without RPE. Cephalometric films were taken before and after treatment, and traditional and Pancherz analysis were used. The average duration of treatment was 10.14 months in group A and 9.77 months in group B respectively (P>0.05). According to Pancherz analysis, maxillary basal bone moved forwards by 2.99 mm in group A and 3.33 mm in group B respectively (P>0.05), mandibular basal bone moved backwards by 0.07 mm in group A, while forwards by 0.80 mm in group B (P>0.05), the overjet increased by 4.51 mm in group A and 6.37 mm in group B respectively (P0.05). The effects were clinically satisfactory in the both groups. Lower molar moved forwards by 1.18 mm in basal bone in group A, while backwards by 1.20 mm in group B (PClass III malocclusion.

  9. Validity of palatal superimposition of 3-dimensional digital models in cases treated with rapid maxillary expansion and maxillary protraction headgear.

    Science.gov (United States)

    Choi, Jin-Il; Cha, Bong-Kuen; Jost-Brinkmann, Paul-Georg; Choi, Dong-Soon; Jang, In-San

    2012-10-01

    The purpose of this study was to evaluate the validity of the 3-dimensional (3D) superimposition method of digital models in patients who received treatment with rapid maxillary expansion (RME) and maxillary protraction headgear. The material consisted of pre- and post-treatment maxillary dental casts and lateral cephalograms of 30 patients, who underwent RME and maxillary protraction headgear treatment. Digital models were superimposed using the palate as a reference area. The movement of the maxillary central incisor and the first molar was measured on superimposed cephalograms and 3D digital models. To determine whether any difference existed between the 2 measuring techniques, intra-class correlation (ICC) and Bland-Altman plots were analyzed. The measurements on the 3D digital models and cephalograms showed a very high correlation in the antero-posterior direction (ICC, 0.956 for central incisor and 0.941 for first molar) and a moderate correlation in the vertical direction (ICC, 0.748 for central incisor and 0.717 for first molar). The 3D model superimposition method using the palate as a reference area is as clinically reliable for assessing antero-posterior tooth movement as cephalometric superimposition, even in cases treated with orthopedic appliances, such as RME and maxillary protraction headgear.

  10. Rapid maxillary expansion versus middle ear tube placement: Comparison of hearing improvements in children with resistance otitis media with effusion.

    Science.gov (United States)

    Kılıç, Nihat; Yörük, Özgür; Kılıç, Songül Cömert; Çatal, Gülhan; Kurt, Sezgin

    2016-09-01

    To test the null hypothesis that there are significant differences in hearing improvements of children with resistance otitis media with effusion (OME) who undergo a rapid maxillary expansion (RME) procedure or ventilation tube placement. Forty-two children between 4.5 and 15 years old were divided into three groups: RME, ventilation tube, and control groups. The RME group consisted of 15 children with maxillary constriction and resistance OME that indicated ventilation tube placement. The ventilation tube group consisted of 16 children for whom ventilation tube placement was indicated but no maxillary constriction. The control group consisted of 11 children with no orthodontic and/or rhinologic problems. Hearing thresholds were evaluated with three audiometric records: (1) before RME/ventilation tube placement (T0); (2) after RME/ventilation tube placement (T1), and (3) after an observation period of 10 months (T2). The control group was matched to these periods, except T1. Hearing thresholds decreased significantly in both the RME and ventilation tube groups (P .05). Slight changes were observed in the control groups. The null hypothesis was rejected. RME showed similar effects as ventilation tube placement for release of otitis media and improvement of hearing thresholds levels. RME should be preferred as a first treatment option for children with maxillary constriction and resistance OME.

  11. Cephalometric variables used to predict the success of interceptive treatment with rapid maxillary expansion and face mask. A longitudinal study

    Directory of Open Access Journals (Sweden)

    Daniele Nóbrega Nardoni

    2015-02-01

    Full Text Available INTRODUCTION: Prognosis is the main limitation of interceptive treatment of Class III malocclusions. The interceptive procedures of rapid maxillary expansion (RME and face mask therapy performed in early mixed dentition are capable of achieving immediate overcorrection and maintenance of facial and occlusal morphology for a few years. Individuals presenting minimal acceptable faces at growth completion are potential candidates for compensatory orthodontic treatment, while those with facial involvement should be submitted to orthodontic decompensation for orthognathic surgery. OBJECTIVES: To investigate cephalometric variables that might predict the outcomes of orthopedic treatment with RME and face mask therapy (FM. METHODS: Cephalometric analysis of 26 Class III patients (mean age of 8 years and 4 months was performed at treatment onset and after a mean period of 6 years and 10 months at pubertal growth completion, including a subjective facial analysis. Patients was divided into two groups: success group (21 individuals and failure group (5 individuals. Discriminant analysis was applied to the cephalometric values at treatment onset. Two predictor variables were found by stepwise procedure. RESULTS: Orthopedic treatment of Class III malocclusion may have unfavorable prognosis at growth completion whenever initial cephalometric analysis reveals increased lower anterior facial height (LAFH combined with reduced angle between the condylar axis and the mandibular plane (CondAx.MP. CONCLUSION: The results of treatment with RME and face mask therapy at growth completion in Class III patients could be predicted with a probability of 88.5%.

  12. Denture-frame modifications in class III patients treated with rapid palatal expansion and facemask: a prospective controlled study.

    Science.gov (United States)

    Migliorati, M; Signori, A; Isaia, L; Menini, A; Rubiano, R; Aonzo, E; Silvestrini Biavati, A

    2015-06-01

    The aim of this prospective controlled investigation was to analyze the short-term cephalometric treatment outcomes, according to the denture frame analysis proposed by Sato, of rapid palatal expansion (RPE) and facial mask (FM) therapy. A group of 21 patients with Class III malocclusion treated with the RPE and FM (TG) was compared with untreated Class III controls (CG). The mean age of treatment group was 8.8 years; treatment consisted of 4 weeks of RPE activation (0.20 mm/die) followed by 14 hours wear of the FM for a mean of 333.1 days. As CG were used the data published by Tanaka and Sato. Pre- and post-treatment cephalometric values were compared and statistical analyzed with one-sample t-test. A P-value plane (POC) values some differences compared to control group were found but they were not statistically significant (P=0.067) while for aterior occlusal plane (POA) no differences where noticed. This study revealed an increase in inter-jaw angle during treatment with FM and RPE, an increase in the inclination of the posterior occlusal plane with respect to the Frankfurt plane and a posterior and lower adaptation of the mandible.

  13. Transverse effects on the nasomaxillary complex one year after rapid maxillary expansion as the only intervention: A controlled study

    Directory of Open Access Journals (Sweden)

    Carolina da Luz Baratieri

    2014-10-01

    Full Text Available The aim of this study was to assess by means of cone-beam computed tomography (CBCT scans the transverse effects on the nasomaxillary complex in patients submitted to rapid maxillary expansion (RME using Haas expander in comparison to untreated individuals. This prospective controlled clinical study assessed 30 subjects (18 boys and 12 girls with mixed dentition and during pubertal growth. The treated group was submitted to RME with Haas expander, retention for six months and a six-month follow-up after removal. The control group matched the treated group in terms of age and sex distribution. CBCT scans were taken at treatment onset and one year after the expander was activated. Maxillary first molars (U6 width, right and left U6 angulation, maxillary alveolar width, maxillary basal width, palatal alveolar width, palatal base width, right and left alveolar angulation, palatal area, nasal base width, nasal cavity width and inferior nasal cavity area on the posterior, middle and anterior coronal slices were measured with Dolphin Imaging Software(r 11.5, except for the first two variables which were performed only on the posterior slice. All transverse dimensions increased significantly (P 0.05. Results suggest that increase of molar, maxillary, palatal and nasal transverse dimensions was stable in comparison to the control group one year after treatment with RME.

  14. Characterization of Diesel and Gasoline Compression Ignition Combustion in a Rapid Compression-Expansion Machine using OH* Chemiluminescence Imaging

    Science.gov (United States)

    Krishnan, Sundar Rajan; Srinivasan, Kalyan Kumar; Stegmeir, Matthew

    2015-11-01

    Direct-injection compression ignition combustion of diesel and gasoline were studied in a rapid compression-expansion machine (RCEM) using high-speed OH* chemiluminescence imaging. The RCEM (bore = 84 mm, stroke = 110-250 mm) was used to simulate engine-like operating conditions at the start of fuel injection. The fuels were supplied by a high-pressure fuel cart with an air-over-fuel pressure amplification system capable of providing fuel injection pressures up to 2000 bar. A production diesel fuel injector was modified to provide a single fuel spray for both diesel and gasoline operation. Time-resolved combustion pressure in the RCEM was measured using a Kistler piezoelectric pressure transducer mounted on the cylinder head and the instantaneous piston displacement was measured using an inductive linear displacement sensor (0.05 mm resolution). Time-resolved, line-of-sight OH* chemiluminescence images were obtained using a Phantom V611 CMOS camera (20.9 kHz @ 512 x 512 pixel resolution, ~ 48 μs time resolution) coupled with a short wave pass filter (cut-off ~ 348 nm). The instantaneous OH* distributions, which indicate high temperature flame regions within the combustion chamber, were used to discern the characteristic differences between diesel and gasoline compression ignition combustion. The authors gratefully acknowledge facilities support for the present work from the Energy Institute at Mississippi State University.

  15. [The effect of two different methods of rapid maxillary expansion on treatment results of skeletal Class III malocclusion patients with maxillary protraction in early permanent dentition].

    Science.gov (United States)

    Chen, Xi-hua; Xie, Xing-qian

    2012-10-01

    To evaluate and compare the effect of single rapid maxillary expansion and repetitive rapid expansion and constriction with maxillary protraction in treating early permanent skeletal Class III patients. Twenty children with skeletal Class III malocclusion were randomly divided into two groups.Ten patients received 1 week of rapid expansion,followed by maxillary protraction(group A) and the other ten patients received 5 weeks of repetitive rapid expansion and constriction followed by maxillary protraction (group B).Cephalometric analysis was performed before and after treatment. The data was analyzed with SPSS 13.0 software package for paired t test. Significant changes in cranio-maxillofacial structures were observed in both groups after 6 months of treatment.Point A moved forward. SNA, ANB, UL-EP, U1-PP, SN-MP, ANS-Me/N-Me, Wit's value increased. L1-MP, LL-EP decreased. Significant differences were found in SNA,ANB,UL-EP between the two groups(PClass III malocclusion patients.

  16. IBO Case Report: Management of Skeletal Class III Malocclusion with Combined Rapid Maxillary Expansion: Facemask Therapy and 5-Year Follow-up

    Directory of Open Access Journals (Sweden)

    Ashok Surana

    2012-01-01

    Full Text Available This case report describes the management of skeletal Class III malocclusion with maxillary deficiency in an adolescent girl, using combined rapid maxillary expansion-facemask approach, followed by comprehensive fixed appliance mechanotherapy. Excellent long-term stability is demonstrated up to 5 years post-treatment.

  17. Estimating the molecular evolutionary rates of mitochondrial genes referring to Quaternary ice age events with inferred population expansions and dispersals in Japanese Apodemus.

    Science.gov (United States)

    Suzuki, Yutaro; Tomozawa, Morihiko; Koizumi, Yuki; Tsuchiya, Kimiyuki; Suzuki, Hitoshi

    2015-09-15

    Determining reliable evolutionary rates of molecular markers is essential in illustrating historical episodes with phylogenetic inferences. Although emerging evidence has suggested a high evolutionary rate for intraspecific genetic variation, it is unclear how long such high evolutionary rates persist because a recent calibration point is rarely available. Other than using fossil evidence, it is possible to estimate evolutionary rates by relying on the well-established temporal framework of the Quaternary glacial cycles that would likely have promoted both rapid expansion events and interisland dispersal events. We examined mitochondrial cytochrome b (Cytb) and control region (CR) gene sequences in two Japanese wood mouse species, Apodemus argenteus and A. speciosus, of temperate origin and found signs of rapid expansion in the population from Hokkaido, the northern island of Japan. Assuming that global warming after the last glacial period 7-10 thousand years before present (kyr BP) was associated with the expansion, the evolutionary rates (sites per million years, myr) of Cytb and CR were estimated as 11-16 % and 22-32 %, respectively, for A. argenteus, and 12-17 % and 17-24 %, respectively, for A. speciosus. Additionally, the significant signature of rapid expansion detected in the mtDNA sequences of A. speciosus from the remaining southern main islands, Honshu, Shikoku, and Kyushu, provided an estimated Cytb evolutionary rate of 3.1 %/site/myr under the assumption of a postglacial population expansion event long ago, most probably at 130 kyr BP. Bayesian analyses using the higher evolutionary rate of 11-17 %/site/myr for Cytb supported the recent demographic or divergence events associated with the Last Glacial Maximum. However, the slower evolutionary rate of 3.1 %/site/myr would be reasonable for several divergence events that were associated with glacial periods older than 130 kyr BP. The faster and slower evolutionary rates of Cytb can account for

  18. Genetic variations in two seahorse species (Hippocampus mohnikei and Hippocampus trimaculatus: evidence for middle Pleistocene population expansion.

    Directory of Open Access Journals (Sweden)

    Yanhong Zhang

    Full Text Available Population genetic of seahorses is confidently influenced by their species-specific ecological requirements and life-history traits. In the present study, partial sequences of mitochondrial cytochrome b (cytb and control region (CR were obtained from 50 Hippocampus mohnikei and 92 H. trimaculatus from four zoogeographical zones. A total of 780 base pairs of cytb gene were sequenced to characterize mitochondrial DNA (mtDNA diversity. The mtDNA marker revealed high haplotype diversity, low nucleotide diversity, and a lack of population structure across both populations of H. mohnikei and H. trimaculatus. A neighbour-joining (NJ tree of cytb gene sequences showed that H. mohnikei haplotypes formed one cluster. A maximum likelihood (ML tree of cytb gene sequences showed that H. trimaculatus belonged to one lineage. The star-like pattern median-joining network of cytb and CR markers indicated a previous demographic expansion of H. mohnikei and H. trimaculatus. The cytb and CR data sets exhibited a unimodal mismatch distribution, which may have resulted from population expansion. Mismatch analysis suggested that the expansion was initiated about 276,000 years ago for H. mohnikei and about 230,000 years ago for H. trimaculatus during the middle Pleistocene period. This study indicates a possible signature of genetic variation and population expansion in two seahorses under complex marine environments.

  19. Postglacial northward expansion and genetic differentiation between migratory and sedentary populations of the broad-tailed hummingbird (Selasphorus platycercus).

    Science.gov (United States)

    Malpica, Andreia; Ornelas, Juan Francisco

    2014-02-01

    Unlike other migratory hummingbirds in North America, the broad-tailed hummingbird (Selasphorus platycercus) exhibits both long-distance migratory behaviour in the USA and sedentary behaviour in Mexico and Guatemala. We examined the evolution of migration linked to its northward expansion using a multiperspective approach. We analysed variation in morphology, mitochondrial and nuclear DNA, estimated migration rates between migratory and sedentary populations, compared divergence times with the occurrence of Quaternary climate events and constructed species distribution models to predict where migratory and sedentary populations resided during the Last Glacial Maximum (LGM) and Last Interglacial (LIG) events. Our results are consistent with a recent northward population expansion driven by migration from southern sedentary populations. Phylogeographical analyses and population genetics methods revealed that migratory populations in the USA and sedentary populations in Mexico of the platycercus subspecies form one admixed population, and that sedentary populations from southern Mexico and Guatemala (guatemalae) undertook independent evolutionary trajectories. Species distribution modelling revealed that the species is a niche tracker and that the climate conditions associated with modern obligate migrants in the USA were not present during the LIG, which provides indirect evidence for recent migratory behaviour in broad-tailed hummingbirds on the temporal scale of glacial cycles. The finding that platycercus hummingbirds form one genetic population and that suitable habitat for migratory populations was observed in eastern Mexico during the LIG also suggests that the conservation of overwintering sites is crucial for obligate migratory populations currently facing climate change effects. © 2013 John Wiley & Sons Ltd.

  20. Comparison and evaluation of stresses generated by rapid maxillary expansion and the implant-supported rapid maxillary expansion on the craniofacial structures using finite element method of stress analysis.

    Science.gov (United States)

    Jain, Varun; Shyagali, Tarulatha R; Kambalyal, Prabhuraj; Rajpara, Yagnesh; Doshi, Jigar

    2017-12-01

    The study aimed to evaluate and compare the stress distribution and 3-dimensional displacements along the craniofacial sutures in between the Rapid maxillary Expansion (RME) and Implant supported RME (I-RME). METHODS: Finite element model of the skull and the implants were created using ANSYS software. The finite element model thus built composed of 537692 elements and 115694 nodes in RME model & 543078 elements and 117948 nodes with implants model. The forces were applied on the palatal surface of the posterior teeth to cause 5mm of transverse displacement on either side of the palatal halves, making it a total of 10mm. The stresses and the displacement values were obtained and interpreted. Varying pattern of stress and the displacements with both positive and negative values were seen. The maximum displacement was seen in the case of plain RME model and that too at Pterygomaxillary suture and Mid-palatal suture in descending order. In the case of I-RME maximum displacement was seen at Zygomaticomaxillary suture followed by Pterygomaxillary suture. The displacements produced in all the three planes of space for the plain RME model were greater in comparison to the Implant Supported RME model. And the stresses remained high for all the sutures in case of an I-RME. There is a definite difference in the stress and the displacement pattern produced by RME and I-RME model and each can be used according to the need of the patient. The stresses generated in case of conventional RME were considerably less than that of the I-RME for all the sutures.

  1. Co-precipitation of ettringite of rapid and slow formation. Consequence: Expansive Synergic Effect. Its demonstration by mortars and concretes

    Directory of Open Access Journals (Sweden)

    Talero, R.

    2011-09-01

    Full Text Available Several prior papers have shown that enough pozzolans can bring about rapid formation ettringite (from its Al2O3r-. It has likewise been found that the formation rate of this ettringite is higher than the of slower forming ettringite originating from OPC (from its C3A. In this context: What type of effect will they ultimately produce? Addition? Synergism? Antagonism? or perhaps Inversion of final expansive action?. To reply to these questions, 4 PC and 12 blended cements containing 20%, 30% or 40% metakaolin, were tested using the ASTM C 452-68, EN 196-1 and RT-86:ΔL tests and also concrete specimens. The experimental results have shows that the joint precipitation in a common sulfate medium, of ettringite from pozzolan and from OPC, was always more synergic than additive, and the technical consequences of the Expansive Synergic Effect may be classified as beneficial, adverse or indifferent according to its sulfates content in excess is more or less adequate.En investigaciones anteriores se ha demostrado que bastantes puzolanas pueden originar ettringita de rápida formación (de su Al2O3r- cuya velocidad es mayor que la de la ettringita de lenta formación, o de origen CPO (de su C3A. En este contexto: ¿qué tipo de efecto será el que produzcan finalmente ambas ettringitas?, ¿adición?, ¿sinergismo?, ¿antagonismo? o ¿inversión de la acción expansiva?. Para responder a estas cuestiones, 4 CPO y 12 cementos con 20%, 30% y 40% de metakaolín fueron ensayados mediante los métodos ASTM C 452-68, EN 196-1 y RT-86:ΔL, y también mediante hormigones. Los resultados obtenidos han demostrado que la precipitación conjunta en un medio selenitoso común, de ettringita de origen puzolana y de origen CPO, es siempre cuantitativamente hablando, más que aditiva, sinérgica, pudiendo ser por ello las consecuencias técnicas del Efecto Sinérgico Expansivo, beneficiosas, adversas o indiferentes, según que el exceso de sulfatos presentes sea más o

  2. Is alternate rapid maxillary expansion and constriction an effective protocol in the treatment of Class III malocclusion? A systematic review.

    Science.gov (United States)

    Pithon, Matheus Melo; Santos, Nathalia de Lima; Santos, Camila Rangel Barreto Dos; Baião, Felipe Carvalho Souza; Pinheiro, Murilo Costa Rangel; Matos, Manoel; Souza, Ianderlei Andrade; Paula, Rafael Pereira de

    2016-01-01

    the treatment of Class III malocclusion in early age is one of the greatest challenges for orthodontists, and the establishment of more effective treatment method is a constant concern for these professionals. Thus, the objective of this systematic review is to verify the effectiveness of the therapy protocol for alternate rapid maxillary expansion and constriction (Alt-RAMEC) in the early treatment of Class III malocclusion. searches were performed in the following electronic databases: Cochrane Library, Medline (EBSCO and PubMed), SciELO, LILACS and Scopus. The following inclusion criteria were used: in vivo studies conducted with early intervention (patient in craniofacial development phase) with the use of the Alt-RAMEC protocol. Reviews, case reports, editorials, and studies with syndromic patients or under use of systemic drug were excluded. Duplicates were also excluded. The studies were assessed for methodological quality using the Cochrane tool for assessment of risk of bias, and classified as high or low risk of bias. 53 articles were found. Duplicates exclusion was thus performed and 35 articles remained. After inclusion analysis, only 5 matched the criteria. Two articles were classified as low risk of bias and three as high risk of bias. It was observed that the Alt-RAMEC enable protraction in less time and with better results, promoting greater effectiveness in the protraction treatment of Class III malocclusion. Although there is positive evidence of the effectiveness of early treatment with the Alt-RAMEC protocol in patients with Class III malocclusion, further studies are needed to confirm its effectiveness using long-term methodology.

  3. Radiation Driven Instability of Rapidly Rotating Relativistic Stars: Criterion and Evolution Equations Via Multipolar Expansion of Gravitational Waves

    Science.gov (United States)

    Chugunov, A. I.

    2017-10-01

    I suggest a novel approach for deriving evolution equations for rapidly rotating relativistic stars affected by radiation-driven Chandrasekhar-Friedman-Schutz instability. This approach is based on the multipolar expansion of gravitational wave emission and appeals to the global physical properties of the star (energy, angular momentum, and thermal state), but not to canonical energy and angular momentum, which is traditional. It leads to simple derivation of the Chandrasekhar-Friedman-Schutz instability criterion for normal modes and the evolution equations for a star, affected by this instability. The approach also gives a precise form to simple explanation of the Chandrasekhar-Friedman-Schutz instability; it occurs when two conditions are met: (a) gravitational wave emission removes angular momentum from the rotating star (thus releasing the rotation energy) and (b) gravitational waves carry less energy, than the released amount of the rotation energy. To illustrate the results, I take the r-mode instability in slowly rotating Newtonian stellar models as an example. It leads to evolution equations, where the emission of gravitational waves directly affects the spin frequency, being in apparent contradiction with widely accepted equations. According to the latter, effective spin frequency decrease is coupled with dissipation of unstable mode, but not with the instability as it is. This problem is shown to be superficial, and arises as a result of specific definition of the effective spin frequency applied previously. Namely, it is shown, that if this definition is taken into account properly, the evolution equations coincide with obtained here in the leading order in mode amplitude. I also argue that the next-to-leading order terms in evolution equations were not yet derived accurately and thus it would be more self-consistent to omit them.

  4. Three-dimensional analysis of maxillary changes associated with facemask and rapid maxillary expansion compared with bone anchored maxillary protraction.

    Science.gov (United States)

    Hino, Claudia Toyama; Cevidanes, Lucia H S; Nguyen, Tung T; De Clerck, Hugo J; Franchi, Lorenzo; McNamara, James A

    2013-11-01

    Our objectives in this study were to evaluate in 3 dimensions the growth and treatment effects on the midface and the maxillary dentition produced by facemask therapy in association with rapid maxillary expansion (RME/FM) compared with bone-anchored maxillary protraction (BAMP). Forty-six patients with Class III malocclusion were treated with either RME/FM (n = 21) or BAMP (n = 25). Three-dimensional models generated from cone-beam computed tomographic scans, taken before and after approximately 1 year of treatment, were registered on the anterior cranial base and measured using color-coded maps and semitransparent overlays. The skeletal changes in the maxilla and the right and left zygomas were on average 2.6 mm in the RME/FM group and 3.7 mm in the BAMP group; these were different statistically. Seven RME/FM patients and 4 BAMP patients had a predominantly vertical displacement of the maxilla. The dental changes at the maxillary incisors were on average 3.2 mm in the RME/FM group and 4.3 mm in the BAMP group. Ten RME/FM patients had greater dental compensations than skeletal changes. This 3-dimensional study shows that orthopedic changes can be obtained with both RME/FM and BAMP treatments, with protraction of the maxilla and the zygomas. Approximately half of the RME/FM patients had greater dental than skeletal changes, and a third of the RME/FM compared with 17% of the BAMP patients had a predominantly vertical maxillary displacement. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  5. The Rapid Reproducers Paradox: Population Control and Individual Procreative Rights

    NARCIS (Netherlands)

    Wissenburg, M.L.J.

    1998-01-01

    In this article, I consider the impact of population policies on individual rights (in a very broad sense of the word), a topic that has received disproportionately little attention in debates on the legitimacy of population rights. I first concentrate on arguments in favour of very radical

  6. Improving Class II malocclusion as a side-effect of rapid maxillary expansion: a prospective clinical study.

    Science.gov (United States)

    Guest, Susan S; McNamara, James A; Baccetti, Tiziano; Franchi, Lorenzo

    2010-11-01

    The objective of this prospective clinical study was to evaluate the dentoalveolar and skeletal effects induced by rapid maxillary expansion (RME) therapy in mixed dentition patients with Class II Division 1 malocclusion compared with a matched untreated Class II Division 1 control group. The treatment sample consisted of cephalometric records of 50 patients with Class II malocclusion (19 boys, 31 girls) treated with an RME protocol including an acrylic splint expander. Some patients also had a removable mandibular Schwarz appliance or maxillary incisor bracketing as part of their treatment protocol. Postexpansion, the patients were stabilized with a removable maintenance plate or a transpalatal arch. The mean age at the start of treatment of the RME group was 8.8 years (T1), with a prephase 2 treatment cephalogram (T2) taken 4.0 years later. The control sample, derived from the records of 3 longitudinal growth studies, consisted of the cephalometric records of 50 Class II subjects (28 boys, 22 girls). The mean age of initial observation for the control group was 8.9 years, and the mean interval of observation was 4.1 years. All subjects in both groups were prepubertal at T1 and showed comparable prevalence rates for prepubertal or postpubertal stages at T2. Independent-sample Student t tests were used to examine between-group differences. Class II patients treated with the described bonded RME protocol showed statistically significant increases in mandibular length and advancement of pogonion relative to nasion perpendicular. The acrylic splint RME had significant effects on the anteroposterior relationship of the maxilla and the mandible, as shown by the improvements toward Class I in the maxillomandibular differential value, the Wits appraisal value, and the ANB angle. Patients treated with the bonded RME showed the greatest effects of therapy at the occlusal level, specifically highly significant improvement of Class II molar relationship and decrease in

  7. Effect of the laser and light-emitting diode (LED) phototherapy on midpalatal suture bone formation after rapid maxilla expansion: a Raman spectroscopy analysis.

    Science.gov (United States)

    Rosa, Cristiane Becher; Habib, Fernando Antonio Lima; de Araújo, Telma Martins; Aragão, Juliana Silveira; Gomes, Rafael Soares; Barbosa, Artur Felipe Santos; Silveira, Landulfo; Pinheiro, Antonio L B

    2014-05-01

    The aim of this study was to analyze the effect of laser or light-emitting diode (LED) phototherapy on the bone formation at the midpalatal suture after rapid maxilla expansion. Twenty young adult male rats were divided into four groups with 8 days of experimental time: group 1, no treatment; group 2, expansion; group 3, expansion and laser irradiation; and group 4, expansion and LED irradiation. In groups 3 and 4, light irradiation was in the first, third, and fifth experimental days. In all groups, the expansion was accomplished with a helicoid 0.020" stainless steel orthodontic spring. A diode laser (λ780 nm, 70 mW, spot of 0.04 cm(2), t = 257 s, spatial average energy fluence (SAEF) of 18 J/cm(2)) or a LED (λ850 nm, 150 mW ± 10 mW, spot of 0.5 cm(2), t = 120 s, SAEF of 18 J/cm(2)) were used. The samples were analyzed by Raman spectroscopy carried out at midpalatal suture and at the cortical area close to the suture. Two Raman shifts were analyzed: ∼ 960 (phosphate hydroxyapatite) and ∼ 1,450 cm(-1) (lipids and protein). Data was submitted to statistical analysis. Significant statistical difference (p ≤ 0.05) was found in the hydroxyapatite (CHA) peaks among the expansion group and the expansion and laser or LED groups. The LED group presented higher mean peak values of CHA. No statistical differences were found between the treated groups as for collagen deposition, although LED also presented higher mean peak values. The results of this study using Raman spectral analysis indicate that laser and LED light irradiation improves deposition of CHA in the midpalatal suture after orthopedic expansion.

  8. Treatment of skeletal class III malocclusion using face mask therapy with alternate rapid maxillary expansion and constriction (Alt-RAMEC) protocol.

    Science.gov (United States)

    Rathi, Anand Ramchandra; Kumari, N Retna; Vadakkepuriyal, Kannan; Santhkumar, Madhu

    2015-01-01

    Class III malocclusion is very common malocclusion and can be due to maxillary retrusion, mandibular prognathism, or combination. Ellis and McNamara found a combination of maxillary retrusion and mandibular protrusion to be the most common skeletal relationship (30%). The treatment should be carried out as early as possible for permitting normal growth of the skeletal bases. Reverse pull head gear combined with maxillary expansion can effectively correct skeletal Class III malocclusion due to maxillary deficiency in growing patient. An eight-year-old female patient with chief complaint of prognathic mandible and anterior crossbite was successfully treated in duration of 5 months with facemask and expansion therapy based on Alternate Rapid Maxillary Expansion and Constriction (Alt-RAMEC) protocol.

  9. Treatment of skeletal class III malocclusion using face mask therapy with alternate rapid maxillary expansion and constriction (Alt-RAMEC protocol

    Directory of Open Access Journals (Sweden)

    Anand Ramchandra Rathi

    2015-01-01

    Full Text Available Class III malocclusion is very common malocclusion and can be due to maxillary retrusion, mandibular prognathism, or combination. Ellis and McNamara found a combination of maxillary retrusion and mandibular protrusion to be the most common skeletal relationship (30%. The treatment should be carried out as early as possible for permitting normal growth of the skeletal bases. Reverse pull head gear combined with maxillary expansion can effectively correct skeletal Class III malocclusion due to maxillary deficiency in growing patient. An eight-year-old female patient with chief complaint of prognathic mandible and anterior crossbite was successfully treated in duration of 5 months with facemask and expansion therapy based on Alternate Rapid Maxillary Expansion and Constriction (Alt-RAMEC protocol.

  10. Monitoring Agricultural Expansion in Burkina Faso over 14 Years with 30 m Resolution Time Series: The Role of Population Growth and Implications for the Environment

    Directory of Open Access Journals (Sweden)

    Kim Knauer

    2017-02-01

    Full Text Available Burkina Faso ranges amongst the fastest growing countries in the world with an annual population growth rate of more than three percent. This trend has consequences for food security since agricultural productivity is still on a comparatively low level in Burkina Faso. In order to compensate for the low productivity, the agricultural areas are expanding quickly. The mapping and monitoring of this expansion is difficult, even on the basis of remote sensing imagery, since the extensive farming practices and frequent cloud coverage in the area make the delineation of cultivated land from other land cover and land use types a challenging task. However, as the rapidly increasing population could have considerable effects on the natural resources and on the regional development of the country, methods for improved mapping of LULCC (land use and land cover change are needed. For this study, we applied the newly developed ESTARFM (Enhanced Spatial and Temporal Adaptive Reflectance Fusion Model framework to generate high temporal (8-day and high spatial (30 m resolution NDVI time series for all of Burkina Faso for the years 2001, 2007, and 2014. For this purpose, more than 500 Landsat scenes and 3000 MODIS scenes were processed with this automated framework. The generated ESTARFM NDVI time series enabled extraction of per-pixel phenological features that all together served as input for the delineation of agricultural areas via random forest classification at 30 m spatial resolution for entire Burkina Faso and the three years. For training and validation, a randomly sampled reference dataset was generated from Google Earth images and based on expert knowledge. The overall accuracies of 92% (2001, 91% (2007, and 91% (2014 indicate the well-functioning of the applied methodology. The results show an expansion of agricultural area of 91% between 2001 and 2014 to a total of 116,900 km². While rainfed agricultural areas account for the major part of this

  11. Post-glacial population expansion of the Monterey Spanish mackerel Scomberomorus concolor in the Gulf of California.

    Science.gov (United States)

    Domínguez-López, M; Díaz-Jaimes, P; Uribe-Alcocer, M; Quiñonez-Velázquez, C

    2015-03-01

    The level of genetic homogeneity and demographic history of the Monterey Spanish mackerel Scomberomorus concolor was assessed by analyses using sequences of the mitochondrial (mt)DNA-control region of samples from the two oceanographic regions of the Gulf of California in order to define the stock structure for this exploited vulnerable species. The data were consistent with a single homogeneous population and revealed the hallmark of fluctuations in population size; these fluctuations appear to have occurred during glacial events of the middle to late Pleistocene, which may in turn be related to the colonization and expansion of S. concolor populations in the gulf. © 2015 The Fisheries Society of the British Isles.

  12. Complete Maxillary Crossbite Correction with a Rapid Palatal Expansion in Mixed Dentition Followed by a Corrective Orthodontic Treatment

    National Research Council Canada - National Science Library

    Tanaka, Orlando Motohiro; Fornazari, Isabelle Adad; Parra, Ariane Ximenes Graciano; Castilhos, Bruno Borges de; Franco, Ademir

    2016-01-01

    .... In phase I, the patient was treated with a modified Haas-type palatal expander, which provided a clinically significant palatal expansion and increased the maxillary arch perimeter with favorable...

  13. Communication and The Challenges of Rapid Population Growth in ...

    African Journals Online (AJOL)

    These factors include religious beliefs, customs and traditions, among others. The discourse also examined the various communication types in Africa and their appropriateness in educating Africans and their governments on the need to control high rate of population growth. Ironically, medical facilities available in African ...

  14. Short-term skeletal and dental changes following bone-borne versus tooth-borne surgically assisted rapid maxillary expansion: a randomized clinical trial study.

    Science.gov (United States)

    Zandi, Mohammad; Miresmaeili, Amirfarhang; Heidari, Ali

    2014-10-01

    To evaluate and compare the short-term (post-retention) skeletal and dental changes following bone-borne and tooth-borne surgically assisted rapid maxillary expansion (SARME) using cone beam computed tomography (CBCT). In this randomized clinical study, 30 patients with transverse maxillary deficiency underwent either tooth-borne (n = 15) or bone-borne (n = 15) SARME. Before treatment and immediately after the consolidation period, CBCT was obtained and the nasal floor width, interdental root distance, palatal bone width and interdental cusp distance were measured at first premolar and first molar regions of maxilla. Twenty eight patients completed the study protocol. In both tooth-borne (n = 13) and bone-borne (n = 15) groups the highest degree of expansion occurred in the dental arch, followed by palatal bone, and nasal floor (V-shaped widening in coronal dimension). The amount and pattern of expansion was comparable between anterior and posterior maxillary regions in each group (parallel posteroanterior expansion) and between the two groups. Dental and skeletal effects of tooth-borne and bone-borne devices were comparable. The overall complication rate was negligible. Selection of an expansion device should be based on each individual patient's requirements. Future long-term clinical trial studies to evaluate the stability and relapse of these two techniques are recommended. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  15. [Treatment of Class II malocclusion using Herbst appliance with headgear and rapid palatal expansion and straight wire appliance with implant anchorage].

    Science.gov (United States)

    Zhang, Xiao-jie; Zheng, Cang-shang; Zhang, Min

    2015-06-01

    To investigate the effects of early treatment of Class II malocclusion with Herbst appliance with headgear and rapid palatal expansion and straight wire appliance with implant anchorage. Twenty-five Chinese children (14 males, 11 females, aged from 10-12 years with an average age of 10.5 years) were treated with Herbst appliance with headgear and rapid palatal expansion for 6 months. Then they were further treated with straight wire appliance with implant anchorage. Cephalometric data pre- and post-treatment were measured and analysed. Multiple correlation analysis was performed with SPSS13.0 software package. Compared with pretreatment, as angle SNB (4.2800±1.4000)° and as angle NP-FH (3.5600±1.0440)° increased posttreatment. as angle SNA (0.5600±0.8206)°, as angle ANB (4.7600±1.2000)°, as angle U1-NA (11.9200±1.4411)° and as angle U1-SN (13.1600±1.7720)° decreased posttreatment (Pheadgear and rapid palatal expansion. The maxillary dentition is significantly retracted by fixed appliance with implant anchorage and the skeletal pattern of patients is significantly improved.

  16. Rapid three dimensional two photon neural population scanning.

    Science.gov (United States)

    Schuck, Renaud; Quicke, Peter; Copeland, Caroline; Garasto, Stefania; Annecchino, Luca A; Hwang, June Kyu; Schultz, Simon R

    2015-08-01

    Recording the activity of neural populations at high sampling rates is a fundamental requirement for understanding computation in neural circuits. Two photon microscopy provides one promising approach towards this. However, neural circuits are three dimensional, and functional imaging in two dimensions fails to capture the 3D nature of neural dynamics. Electrically tunable lenses (ETLs) provide a simple and cheap method to extend laser scanning microscopy into the relatively unexploited third dimension. We have therefore incorporated them into our Adaptive Spiral Scanning (SSA) algorithm, which calculates kinematically efficient scanning strategies using radially modulated spiral paths. We characterised the response of the ETL, incorporated its dynamics using MATLAB models of the SSA algorithm and tested the models on populations of Izhikevich neurons of varying size and density. From this, we show that our algorithms can theoretically at least achieve sampling rates of 36.2Hz compared to 21.6Hz previously reported for 3D scanning techniques.

  17. Rapid population growth and environmental degradation: ultimate versus proximate factors.

    Science.gov (United States)

    Shaw, R P

    1989-01-01

    This philosophical review of 2 arguments about responsibility for and solutions to environmental degradation concludes that both sides are correct: the ultimate and the proximal causes. Ultimate causes of pollution are defined as the technology responsible for a given type of pollution, such as burning fossil fuel; proximate causes are defined as situation-specific factors confounding the problem, such as population density or rate of growth. Commoner and others argue that developed countries with low or negative population growth rates are responsible for 80% of world pollution, primarily in polluting technologies such as automobiles, power generation, plastics, pesticides, toxic wastes, garbage, warfaring, and nuclear weapons wastes. Distortionary policies also contribute; examples are agricultural trade protection, land mismanagement, urban bias in expenditures, and institutional rigidity., Poor nations are responsible for very little pollution because poverty allows little waste or expenditures for polluting, synthetic technologies. The proximal causes of pollution include numbers and rate of growth of populations responsible for the pollution. Since change in the ultimate cause of pollution remains out of reach, altering the numbers of polluters can make a difference. Predictions are made for proportions of the world's total waste production, assuming current 1.6 tons/capita for developed countries and 0.17 tons/capita for developing countries. If developing countries grow at current rates and become more wealthy, they will be emitting half the world's waste by 2025. ON the other hand, unsustainable population growth goes along with inadequate investment in human capital: education, health, employment, infrastructure. The solution is to improve farming technologies in the 117 non-self-sufficient countries, fund development in the most unsustainable enclaves of growing countries, break institutionalized socio-political rigidity in these enclaves, and focus on

  18. Rapid and Sensitive Detection of BLAD in Cattle Population

    Directory of Open Access Journals (Sweden)

    Daniela Elena Ilie

    2014-05-01

    Full Text Available Bovine leukocyte adhesion deficiency (BLAD is an autosomal recessive disorder with negative impact on dairy cattle breeding. The molecular basis of BLAD is a single point mutation (A→G, resulting in a single amino acid substitution (aspartic acid → glycine at amino acid 128 in the adhesion molecule CD18. The object of this study was to establish a fast and sensitive molecular genotyping assay to detect BLAD carriers using high-resolution melting (HRM curve analysis. We tested animals with known genotypes for BLAD that were previously confirmed by PCR-RFLP method, and then examined the sensitivity of mutation detection using PCR followed by HRM curve analysis. BLAD carriers were readily detectable using HRM assay. Thus, the PCR-HRM genotyping method is a rapid, easily interpretable, reliable and cost-effective assay for BLAD mutant allele detection. This assay can be useful in cattle genotyping and genetic selection.

  19. Displacements prediction from 3D finite element model of maxillary protraction with and without rapid maxillary expansion in a patient with unilateral cleft palate and alveolus.

    Science.gov (United States)

    Zhang, Dan; Zheng, Li; Wang, Qiang; Lu, Li; Ma, Jia

    2015-08-19

    Both maxillary protraction and rapid expansion are recommended for patients with cleft palate and alveolus. The aim of the study is to establish a three-dimensional finite element model of the craniomaxillary complex with unilateral cleft palate and alveolus to simulate maxillary protraction with and without rapid maxillary expansion. The study also investigates the deformation of the craniomaxillary complex after applied orthopaedic forces in different directions. A three dimensional finite element model of 1,277,568 hexahedral elements (C3D8) and 1,801,945 nodes was established based upon CT scan of a patient with unilateral cleft palate and alveolus on the right side in this study. A force of 4.9 N per side was directed on the anatomic height of contour on the buccal side of the first molar. The angles between the force vector and occlusal plane were -30°, -20°, -10°, 0°, 10°, 20°, and 30°. A force of 2.45 N on each loading point was directed on the anatomic height of contour on the lingual side of the first premolar and the first molar to simulate the expansion of the palate. The craniomaxillary complex displaced forward under any of the loading conditions. The sagittal and vertical displacement of the craniomaxillary complex reached their peak at the protraction degree of -10° forward and downward to the occlusal plane. There were larger sagittal displacements when the maxilla was protracted forward with maxillary expansion. The palatal plane rotated counterclockwise under any of the loading conditions. Being protracted without expansion, the dental arch was constricted. When supplemented with maxillary expansion, the width of the dental arch increased. Transverse deformation of the dental arch on affected side was different from that on unaffected side. Protraction force alone led the craniomaxillary complex moved forward and counterclockwise, accompanied with lateral constrain on the dental arch. Additional rapid maxillary expansion resulted in a

  20. Effects of low-level laser therapy on osteoblastic bone formation and relapse in an experimental rapid maxillary expansion model.

    Science.gov (United States)

    Aras, M H; Erkilic, S; Demir, T; Demirkol, M; Kaplan, D S; Yolcu, U

    2015-01-01

    The aim of this study was to investigate the effects of low-level laser therapy (LLLT) on osteoblastic bone formation and relapse during expansion of rat palatal sutures. Thirty-two Wistar rats were randomly allocated into two groups of 16 rats each. In the first group, LLLT was applied 4 days after expansion commenced. Seven days after expansion, retainers were applied for 10 days. The second group was similarly treated, with the exception of laser therapy. All rats were sacrificed on day 7 (n = 1) (the end of the expansion period; laser group (LG) 1 [LLLT 1] and control group (CG) 1 [control 1]) and day 17 (n = 8) (the end of the retention period; LG 2 [LLLT 2] and CG 2 [control 2]) for histological assessment. The LLLT 1 group had significantly higher numbers of osteoclasts than did the control 1 group (P = 0.036). No significant between-group difference in osteoblast cell or capillary numbers was evident when day 7 and 17 data were compared. Histologically, LLLT stimulated bone formation, as revealed by analysis after the retention period. LLLT during expansion may accelerate bone healing.

  1. Analysis of the dentoalveolar effects of slow and rapid maxillary expansion in complete bilateral cleft lip and palate patients: a randomized clinical trial.

    Science.gov (United States)

    de Medeiros Alves, Arthur César; Garib, Daniela Gamba; Janson, Guilherme; de Almeida, Araci Malagodi; Calil, Louise Resti

    2016-09-01

    The purpose of this study was to compare the dentoalveolar effects of slow (SME) and rapid (RME) maxillary expansions in patients with complete bilateral cleft lip and palate (BCLP). A sample of 50 patients with BCLP and maxillary arch constriction was randomly and equally allocated into two groups. Group SME comprised patients (mean age of 8.8 years) treated with quad-helix appliance. Group RME comprised individuals (mean age of 8.9 years) treated with Hyrax expander. Digital dental models obtained immediately pre-expansion (T1) and 6 months after the active expansion period (T2) were used for measuring maxillary dental arch widths, arch perimeter, arch length, palatal depth, buccolingual inclination of posterior teeth and differential amount of expansion accomplished at the canine and molar regions. Inter-phase and intergroup comparisons were performed using paired t tests and t tests, respectively (p < 0.05). SME and RME caused significant increase of arch widths and arch perimeter. Arch length and palatal depth decreased nonsignificantly with SME but significantly with RME. Buccal tooth inclination was significant only for maxillary deciduous canines in both groups. The quad-helix appliance showed a significant differential expansion between anterior and posterior regions. No differences were observed between SME and RME for all variables. Differences were not found between the dentoalveolar effects of SME and RME in patients with BCLP. SME demanded a greater therapy time compared to RME. Both expansion procedures can be similarly indicated to correct maxillary arch constriction in patients with BCLP in the mixed dentition.

  2. Comparison of the treatment effects of different rapid maxillary expansion devices on the maxilla and the mandible. Part 1: Evaluation of dentoalveolar changes.

    Science.gov (United States)

    Canan, Selin; Şenışık, Neslihan Ebru

    2017-06-01

    The aim of this study was to compare the dentoalveolar treatment effects of 3 rapid maxillary expansion (RME) appliances, supported by different tissues, on the maxilla and the mandible. Patients were assessed for eligibility, and those who met the requirements and agreed to participate were enrolled in the study. Participants were randomly allocated into 3 groups, depending on the type of expansion. The tooth-borne group (n = 16; ages, 12.63 ± 1.36 years) had RME with a tooth-borne appliance; the bone-borne group (n = 16; ages, 12.92 ± 1.07 years) had RME with a bone-borne appliance; and the hybrid group (n = 15; ages, 13.41 ± 0.88 years) had RME with hybrid appliances. Dentoalveolar effects were evaluated by digitally superimposed 3-dimensional scans of maxillary dental casts on a coordinate system and linear interdental width measurements of mandibular dental casts in the pretreatment, posttreatment, and postretention periods. For intragroup and intergroup comparisons, 1-way analysis of variance for repeated measures and multivariate analysis of variance were performed, respectively. Similar dentoalveolar treatment effects were achieved in all groups with the exception of a small amount of expansion on the right side in the bone-borne group. All 3 expanders led to the expansion of maxillary dentoalveolar structures with mild relapse. However, the amount of expansion of the bone-borne expander on the right side was statistically lower. Spontaneous interdental expansion was observed in the mandibular dentitions in all groups. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  3. Population increase in Kirtland's warbler and summer range expansion to Wisconsin and Michigan's Upper Peninsula, USA

    Science.gov (United States)

    John R. Probst; Deahn M. Donner; Carol I. Bocetti; Steve Sjogren

    2003-01-01

    The threatened Kirtland's warbler Dendroica kirtlandii breeds in stands of young jack pine Pinus banksiana growing on well-drained soils in Michigan, USA. We summarize information documenting the range expansion of Kirtland's warbler due to increased habitat management in the core breeding range in the Lower Peninsula of...

  4. Mitochondrial DNA Analyses Indicate High Diversity, Expansive Population Growth and High Genetic Connectivity of Vent Copepods (Dirivultidae) across Different Oceans.

    Science.gov (United States)

    Gollner, Sabine; Stuckas, Heiko; Kihara, Terue C; Laurent, Stefan; Kodami, Sahar; Martinez Arbizu, Pedro

    2016-01-01

    Communities in spatially fragmented deep-sea hydrothermal vents rich in polymetallic sulfides could soon face major disturbance events due to deep-sea mineral mining, such that unraveling patterns of gene flow between hydrothermal vent populations will be an important step in the development of conservation policies. Indeed, the time required by deep-sea populations to recover following habitat perturbations depends both on the direction of gene flow and the number of migrants available for re-colonization after disturbance. In this study we compare nine dirivultid copepod species across various geological settings. We analyze partial nucleotide sequences of the mtCOI gene and use divergence estimates (FST) and haplotype networks to infer intraspecific population connectivity between vent sites. Furthermore, we evaluate contrasting scenarios of demographic population expansion/decline versus constant population size (using, for example, Tajima's D). Our results indicate high diversity, population expansion and high connectivity of all copepod populations in all oceans. For example, haplotype diversity values range from 0.89 to 1 and FST values range from 0.001 to 0.11 for Stygiopontius species from the Central Indian Ridge, Mid Atlantic Ridge, East Pacific Rise, and Eastern Lau Spreading Center. We suggest that great abundance and high site occupancy by these species favor high genetic diversity. Two scenarios both showed similarly high connectivity: fast spreading centers with little distance between vent fields and slow spreading centers with greater distance between fields. This unexpected result may be due to some distinct frequency of natural disturbance events, or to aspects of individual life histories that affect realized rates of dispersal. However, our statistical performance analyses showed that at least 100 genomic regions should be sequenced to ensure accurate estimates of migration rate. Our demography parameters demonstrate that dirivultid

  5. Genetic diversity and structure related to expansion history and habitat isolation: stone marten populating rural-urban habitats.

    Science.gov (United States)

    Wereszczuk, Anna; Leblois, Raphaël; Zalewski, Andrzej

    2017-12-22

    Population genetic diversity and structure are determined by past and current evolutionary processes, among which spatially limited dispersal, genetic drift, and shifts in species distribution boundaries have major effects. In most wildlife species, environmental modifications by humans often lead to contraction of species' ranges and/or limit their dispersal by acting as environmental barriers. However, in species well adapted to anthropogenic habitat or open landscapes, human induced environmental changes may facilitate dispersal and range expansions. In this study, we analysed whether isolation by distance and deforestation, among other environmental features, promotes or restricts dispersal and expansion in stone marten (Martes foina) populations. We genotyped 298 martens from eight sites at twenty-two microsatellite loci to characterize the genetic variability, population structure and demographic history of stone martens in Poland. At the landscape scale, limited genetic differentiation between sites in a mosaic of urban, rural and forest habitats was mostly influenced by isolation by distance. Statistical clustering and multivariate analyses showed weak genetic structuring with two to four clusters and a high rate of gene flow between them. Stronger genetic differentiation was detected for one stone marten population (NE1) located inside a large forest complex. Genetic differentiation between this site and all others was 20% higher than between other sites separated by similar distances. The genetic uniqueness index of NE1 was also twofold higher than in other sites. Past demographic history analyses showed recent expansion of this species in north-eastern Poland. A decrease in genetic diversity from south to north, and MIGRAINE analyses indicated the direction of expansion of stone marten. Our results showed that two processes, changes in species distribution boundaries and limited dispersal associated with landscape barriers, affect genetic diversity and

  6. Transfer of genetic therapy across human populations: molecular targets for increasing patient coverage in repeat expansion diseases.

    Science.gov (United States)

    Varela, Miguel A; Curtis, Helen J; Douglas, Andrew G L; Hammond, Suzan M; O'Loughlin, Aisling J; Sobrido, Maria J; Scholefield, Janine; Wood, Matthew J A

    2016-02-01

    Allele-specific gene therapy aims to silence expression of mutant alleles through targeting of disease-linked single-nucleotide polymorphisms (SNPs). However, SNP linkage to disease varies between populations, making such molecular therapies applicable only to a subset of patients. Moreover, not all SNPs have the molecular features necessary for potent gene silencing. Here we provide knowledge to allow the maximisation of patient coverage by building a comprehensive understanding of SNPs ranked according to their predicted suitability toward allele-specific silencing in 14 repeat expansion diseases: amyotrophic lateral sclerosis and frontotemporal dementia, dentatorubral-pallidoluysian atrophy, myotonic dystrophy 1, myotonic dystrophy 2, Huntington's disease and several spinocerebellar ataxias. Our systematic analysis of DNA sequence variation shows that most annotated SNPs are not suitable for potent allele-specific silencing across populations because of suboptimal sequence features and low variability (>97% in HD). We suggest maximising patient coverage by selecting SNPs with high heterozygosity across populations, and preferentially targeting SNPs that lead to purine:purine mismatches in wild-type alleles to obtain potent allele-specific silencing. We therefore provide fundamental knowledge on strategies for optimising patient coverage of therapeutics for microsatellite expansion disorders by linking analysis of population genetic variation to the selection of molecular targets.

  7. Evolution in an Afternoon: Rapid Natural Selection and Adaptation of Bacterial Populations

    Science.gov (United States)

    Delpech, Roger

    2009-01-01

    This paper describes a simple, rapid and low-cost technique for growing bacteria (or other microbes) in an environmental gradient, in order to determine the tolerance of the microbial population to varying concentrations of sodium chloride ions, and suggests how the evolutionary response of a microbial population to the selection pressure of the…

  8. Complete Maxillary Crossbite Correction with a Rapid Palatal Expansion in Mixed Dentition Followed by a Corrective Orthodontic Treatment

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    Orlando Motohiro Tanaka

    2016-01-01

    Full Text Available This case report presents the interceptive orthodontic treatment of a boy, aged 8 years 4 months with a Class I malocclusion with severe transverse maxillary deficiency and complete maxillary crossbite and correction using Haas expansion and fixed appliance. The treatment goals were to correct the posterior crossbite and anterior crossbite and restore the normality of the dentition and occlusion. In phase I, the patient was treated with a modified Haas-type palatal expander, which provided a clinically significant palatal expansion and increased the maxillary arch perimeter with favorable conditions for orthodontic treatment with fixed appliances in phase II. The optimization of E-space and the use of intermaxillary Class III elastics helped to maintain the mandibular incisors upright. A removable wraparound type appliance and a bonded lingual canine-to-canine retainer were used as retention. Although the literature has reported a high rate of relapse after palatal expansion, after 2 years 9 months of posttreatment follow-up, the occlusal result was stable and no skeletal reversals could be detected.

  9. Northern range expansion of European populations of the wasp spider Argiope bruennichi is associated with global warming-correlated genetic admixture and population-specific temperature adaptations.

    Science.gov (United States)

    Krehenwinkel, Henrik; Tautz, Diethard

    2013-04-01

    Poleward range expansions are observed for an increasing number of species, which may be an effect of global warming during the past decades. However, it is still not clear in how far these expansions reflect simple geographical shifts of species ranges, or whether new genetic adaptations play a role as well. Here, we analyse the expansion of the wasp spider Argiope bruennichi into Northern Europe during the last century. We have used a range-wide sampling of contemporary populations and historical specimens from museums to trace the phylogeography and genetic changes associated with the range shift. Based on the analysis of mitochondrial, microsatellite and SNP markers, we observe a higher level of genetic diversity in the expanding populations, apparently due to admixture of formerly isolated lineages. Using reciprocal transplant experiments for testing overwintering tolerance, as well as temperature preference and tolerance tests in the laboratory, we find that the invading spiders have possibly shifted their temperature niche. This may be a key adaptation for survival in Northern latitudes. The museum samples allow a reconstruction of the invasion's genetic history. A first, small-scale range shift started around 1930, in parallel with the onset of global warming. A more massive invasion of Northern Europe associated with genetic admixture and morphological changes occurred in later decades. We suggest that the latter range expansion into far Northern latitudes may be a consequence of the admixture that provided the genetic material for adaptations to new environmental regimes. Hence, global warming could have facilitated the initial admixture of populations and this resulted in genetic lineages with new habitat preferences. © 2013 Blackwell Publishing Ltd.

  10. Effects of rapid maxillary expansion and mandibular advancement on upper airways in Marfan's syndrome children: a home sleep study and cephalometric evaluation.

    Science.gov (United States)

    Taddei, M; Alkhamis, N; Tagariello, T; D'Alessandro, G; Mariucci, E M; Piana, G

    2015-12-01

    Evaluation of the effects of rapid maxillary expansion and mandibular advancement using Propulsor Universal Light appliance on the upper airways in Marfan's syndrome children through home sleep studies, Epworth Sleepiness Scale questionnaire, and cephalometric analysis of the upper airways on lateral radiographs. The study sample consisted of 30 children with Marfan's syndrome, and the control group consisted of 30 untreated and matched children. For Marfan subjects, data were taken at different time points compared to treatment: at T0 (before treatment), T1 (after rapid maxillary expansion), and T2 (after mandibular advancement). For control subjects, data were taken at similar intervals, at three follow-up visits: at T0 (as a starting screening tool), T1 (after approximately 2 years), and T2 (in proximity of the peak skeletal growth). Apnea-hypopnea and oxygen desaturations were significantly higher in the study group at T0 and T1 compared with control children. At T2, the values were not significant (p value 0.442 for both apnea-hypopnea index (AHI) and oxygen desaturation index (ODI)). Horizontal airway dimensions were significantly reduced, and vertical airway values were significantly increased in Marfan's syndrome at T0 and T1 but not at T2 (p values at T2: 0.071 for Phw1-Psp, 0.106 for Phw1-Psp', 0.101 for Phw2-Tb, 0.559 for UAL in male and 0.560 for UAL in female). Early rapid maxillary expansion and mandibular advancement using Propulsor Universal Light appliance significantly improved airway patency of Marfan's syndrome children and are strongly encouraged as a routine treatment for both correction of class II malocclusions and prevention of obstructive sleep apnea.

  11. Effects of Pterygomaxillary Separation on Skeletal and Dental Changes After Surgically Assisted Rapid Maxillary Expansion: A Single-Center, Double-Blind, Randomized Clinical Trial.

    Science.gov (United States)

    Ferraro-Bezerra, Marcelo; Tavares, Rodrygo Nunes; de Medeiros, José Rômulo; Nogueira, Alexandre Simões; Avelar, Rafael Linard; Studart Soares, Eduardo Costa

    2017-08-31

    Surgically assisted rapid maxillary expansion (SARME) is a procedure routinely performed to correct transverse maxillary deformities and can be performed with or without pterygomaxillary disjunction (PD). The aim of the present study was to measure the effect of the amount of expansion and stability of SARME with or without PD. We designed and implemented a double-blind, randomized clinical trial. The patients were randomly assigned to 2 groups: group 1, SARME without PD; and group 2, SARME with PD. Cone-beam computed tomography scans were performed at 3 points: baseline (T0), after maxillary expansion (T1), and at the end of the retention period (T2). Dental and bone expansion and dental inclination at the maxillary canine and first molar regions were assessed. Two-way repeated measures analysis of variance was used to evaluate the differences between the 2 groups at the 3 evaluation periods (T0, T1, and T2), using a level of significance of P patients underwent maxillary surgical expansion (group 1, n = 12; and group 2, n = 12). Both techniques promoted a significant transverse dental expansion in the first molar at T2 (with PD, 5.4 mm; vs without PD, 6.4 mm; change, -6.18 mm to 1.48 mm). However, no statistically significant differences were observed between the 2 groups. The tipping molars at T2 remained at a higher level in the SARME, no PD group than in the SARME, PD group (with PD, 2.3°; vs no PD, 4.6° for 3 teeth; change, -12.72° to 5.57°; and with PD, 1.6° vs without PD, 3.6° for 14 teeth; change, -9.96° to 9.83°). SARME with and without PD is a reliable method for obtaining maxillary expansion, with slight differences in the patterns of skeletal and dental alterations. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  12. South American Plasmodium falciparum after the malaria eradication era: clonal population expansion and survival of the fittest hybrids.

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    Sean M Griffing

    Full Text Available Malaria has reemerged in many regions where once it was nearly eliminated. Yet the source of these parasites, the process of repopulation, their population structure, and dynamics are ill defined. Peru was one of malaria eradication's successes, where Plasmodium falciparum was nearly eliminated for two decades. It reemerged in the 1990s. In the new era of malaria elimination, Peruvian P. falciparum is a model of malaria reinvasion. We investigated its population structure and drug resistance profiles. We hypothesized that only populations adapted to local ecological niches could expand and repopulate and originated as vestigial populations or recent introductions. We investigated the genetic structure (using microsatellites and drug resistant genotypes of 220 parasites collected from patients immediately after peak epidemic expansion (1999-2000 from seven sites across the country. The majority of parasites could be grouped into five clonal lineages by networks and AMOVA. The distribution of clonal lineages and their drug sensitivity profiles suggested geographic structure. In 2001, artesunate combination therapy was introduced in Peru. We tested 62 parasites collected in 2006-2007 for changes in genetic structure. Clonal lineages had recombined under selection for the fittest parasites. Our findings illustrate that local adaptations in the post-eradication era have contributed to clonal lineage expansion. Within the shifting confluence of drug policy and malaria incidence, populations continue to evolve through genetic outcrossing influenced by antimalarial selection pressure. Understanding the population substructure of P. falciparum has implications for vaccine, drug, and epidemiologic studies, including monitoring malaria during and after the elimination phase.

  13. Phylogeographic and population insights of the Asian common toad (Bufo gargarizans in Korea and China: population isolation and expansions as response to the ice ages

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    Amaël Borzée

    2017-11-01

    Full Text Available The effects of ice ages on speciation have been well documented for many European and North American taxa. In contrast, very few studies have addressed the consequences of such environmental and topographical changes in North East Asian species. More precisely, the Korean Peninsula offers a unique model to assess patterns and processes of speciation as it hosts the northern- and eastern-most distribution limit of some widespread Asian taxa. Despite this, studies addressing phylogeographic patterns and population genetics in the peninsula and surrounding countries are few and studies for most families are lacking. Here we inferred the phylogenetic relationships of the common toad (Bufo gargarizans from South Korea and their North East Asian counterpart populations, based on mitochondrial data. Korean B. gargarizans GenBank BLASTs matched few individuals from nearby China, but the presence of a Korean clade suggests isolation on the Korean Peninsula, previous to the last glacial maximum, linked to sea level resurgence. Molecular clock calibrations within this group were used to date the divergence between clades and their relationship to paleo-climatic events in the area. Lack of genetic structure among South Korean populations and strong homogeneity between the Korean and some Chinese localities suggest weak isolation and recent expansion. Geographical projection of continuous coalescent maximum-clade-credibility trees shows an original Chinese expansion towards the Korean Peninsula through the Yellow Sea circa two million years ago with colonisation events dating circa 800 thousand years ago (K. y. a.. Following this colonisation, the data point to outgoing Korean Peninsula dispersal events throughout different periods, towards the North through land, and West through land bridge formations over the Yellow Sea during sea level falls. In accordance, demographic analyses revealed a population expansion in the Koran Peninsula circa 300 K. y. a

  14. Phylogeographic and population insights of the Asian common toad (Bufo gargarizans) in Korea and China: population isolation and expansions as response to the ice ages.

    Science.gov (United States)

    Borzée, Amaël; Santos, Joana L; Sánchez-RamÍrez, Santiago; Bae, Yoonhyuk; Heo, Kyongman; Jang, Yikweon; Jowers, Michael Joseph

    2017-01-01

    The effects of ice ages on speciation have been well documented for many European and North American taxa. In contrast, very few studies have addressed the consequences of such environmental and topographical changes in North East Asian species. More precisely, the Korean Peninsula offers a unique model to assess patterns and processes of speciation as it hosts the northern- and eastern-most distribution limit of some widespread Asian taxa. Despite this, studies addressing phylogeographic patterns and population genetics in the peninsula and surrounding countries are few and studies for most families are lacking. Here we inferred the phylogenetic relationships of the common toad ( Bufo gargarizans ) from South Korea and their North East Asian counterpart populations, based on mitochondrial data. Korean B. gargarizans GenBank BLASTs matched few individuals from nearby China, but the presence of a Korean clade suggests isolation on the Korean Peninsula, previous to the last glacial maximum, linked to sea level resurgence. Molecular clock calibrations within this group were used to date the divergence between clades and their relationship to paleo-climatic events in the area. Lack of genetic structure among South Korean populations and strong homogeneity between the Korean and some Chinese localities suggest weak isolation and recent expansion. Geographical projection of continuous coalescent maximum-clade-credibility trees shows an original Chinese expansion towards the Korean Peninsula through the Yellow Sea circa two million years ago with colonisation events dating circa 800 thousand years ago (K. y. a.). Following this colonisation, the data point to outgoing Korean Peninsula dispersal events throughout different periods, towards the North through land, and West through land bridge formations over the Yellow Sea during sea level falls. In accordance, demographic analyses revealed a population expansion in the Koran Peninsula circa 300 K. y. a., likely attributed

  15. Assessment of the dental and skeletal effects of fan-type rapid maxillary expansion screw and Hyrax screw on craniofacial structures

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    Umarevathi Gopalakrishnan

    2017-01-01

    Full Text Available Aims and Objectives: The purpose of the study was to assess the skeletal and dental effects of fan-type rapid maxillary expansion (RME appliance and Hyrax RME appliance on the craniofacial structures. Materials and Methods: The sample of the study included 12 patients with constricted maxillary arches. Acrylic bonded type of attachment was used for both groups. Changes in sagittal, vertical, and transverse relationship were assessed with lateral and frontal cephalograms, respectively. Intercanine and intermolar widths were measured with stone models. Pre- and immediate post-treatment records were statistically analyzed with Wilcoxon signed-rank test. The differences between the groups were evaluated using Mann–Whitney U-test. Since the data pertaining to intercanine width and intermolar width were normally distributed, parametric test of signifi cance (unpaired t-test was used to compare them. Results: Results showed that Hyrax presented with signifi cantly greater increments for both nasal cavity width and maxillary width when compared to fan-type RME. Both groups had retroclination of incisors. The increase in the intercanine width was almost similar in both groups. Conclusion: Fan-type RME caused only minimal expansion of the intermolar width when compared to the Hyrax. The ratio between the intercanine and intermolar width expansion was nearly 4:1 in the fan-type RME and 0.75:1 in Hyrax.

  16. Three-Dimensional Finite Element Analysis of Stress Distribution and Displacement of the Maxilla Following Surgically Assisted Rapid Maxillary Expansion with Tooth- and Bone-Borne Devices.

    Science.gov (United States)

    Dalband, Mohsen; Kashani, Jamal; Hashemzehi, Hadi

    2015-04-01

    The aim of this study was to investigate the displacement and stress distribution during surgically assisted rapid maxillary expansion under different surgical conditions with tooth- and bone-borne devices. Three-dimensional (3D) finite element model of a maxilla was constructed and an expansion force of 100 N was applied to the left and right molars and premolars with tooth-borne devices and the left and right of mid-palatal sutures at the first molar level with bone-borne devices. Five computer-aided design (CAD) models were simulated as follows and surgical procedures were used: G1: control group (without surgery); G2: Le Fort I osteotomy; G3: Le Fort I osteotomy and para-median osteotomy; G4: Le Fort I osteotomy and pterygomaxillary separation; and G5: Le Fort I osteotomy, para-median osteotomy, and pterygomaxillary separation. Maxillary displacement showed a gradual increase from G1 to G5 in all three planes of space, indicating that Le Fort I osteotomy combined with para-median osteotomy and pterygomaxillary separation produced the greatest displacement of the maxilla with both bone- and tooth-borne devices. Surgical relief and bone-borne devices resulted in significantly reduced stress on anchored teeth. Combination of Le Fort I and para-median osteotomy with pterygomaxillary separation seems to be an effective procedure for increasing maxillary expansion, and excessive stress side effects are lowered around the anchored teeth with the use of bone-borne devices.

  17. A timescale for evolution, population expansion, and spatial spread of an emerging clone of methicillin-resistant Staphylococcus aureus.

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    Ulrich Nübel

    2010-04-01

    Full Text Available Due to the lack of fossil evidence, the timescales of bacterial evolution are largely unknown. The speed with which genetic change accumulates in populations of pathogenic bacteria, however, is a key parameter that is crucial for understanding the emergence of traits such as increased virulence or antibiotic resistance, together with the forces driving pathogen spread. Methicillin-resistant Staphylococcus aureus (MRSA is a common cause of hospital-acquired infections. We have investigated an MRSA strain (ST225 that is highly prevalent in hospitals in Central Europe. By using mutation discovery at 269 genetic loci (118,804 basepairs within an international isolate collection, we ascertained extremely low diversity among European ST225 isolates, indicating that a recent population bottleneck had preceded the expansion of this clone. In contrast, US isolates were more divergent, suggesting they represent the ancestral population. While diversity was low, however, our results demonstrate that the short-term evolutionary rate in this natural population of MRSA resulted in the accumulation of measurable DNA sequence variation within two decades, which we could exploit to reconstruct its recent demographic history and the spatiotemporal dynamics of spread. By applying Bayesian coalescent methods on DNA sequences serially sampled through time, we estimated that ST225 had diverged since approximately 1990 (1987 to 1994, and that expansion of the European clade began in 1995 (1991 to 1999, several years before the new clone was recognized. Demographic analysis based on DNA sequence variation indicated a sharp increase of bacterial population size from 2001 to 2004, which is concordant with the reported prevalence of this strain in several European countries. A detailed ancestry-based reconstruction of the spatiotemporal dispersal dynamics suggested a pattern of frequent transmission of the ST225 clone among hospitals within Central Europe. In addition

  18. Rapid climate change did not cause population collapse at the end of the European Bronze Age.

    Science.gov (United States)

    Armit, Ian; Swindles, Graeme T; Becker, Katharina; Plunkett, Gill; Blaauw, Maarten

    2014-12-02

    The impact of rapid climate change on contemporary human populations is of global concern. To contextualize our understanding of human responses to rapid climate change it is necessary to examine the archeological record during past climate transitions. One episode of abrupt climate change has been correlated with societal collapse at the end of the northwestern European Bronze Age. We apply new methods to interrogate archeological and paleoclimate data for this transition in Ireland at a higher level of precision than has previously been possible. We analyze archeological (14)C dates to demonstrate dramatic population collapse and present high-precision proxy climate data, analyzed through Bayesian methods, to provide evidence for a rapid climatic transition at ca. 750 calibrated years B.C. Our results demonstrate that this climatic downturn did not initiate population collapse and highlight the nondeterministic nature of human responses to past climate change.

  19. Alterações no volume nasal de pacientes submetidos a disjunção da maxila Changes in nasal volume of patients undergoing rapid maxillary expansion

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    Renata da Fonseca Lacerda e Muniz

    2008-02-01

    Full Text Available Os efeitos da disjunção maxilar na resistência nasal e fluxo aéreo têm sido amplamente discutidos na literatura, com controvérsias. Suas indicações esqueléticas e dentárias parecem estar bem claras. Porém, aquelas puramente rinológicas não são justificadas, porque nem sempre resultados positivos são encontrados. Este estudo teve por finalidade avaliar a repercussão da disjunção maxilar ortopédica no aspecto respiratório e rinológico dos pacientes submetidos a esse procedimento.Rapid maxillary expansion effects on airflow and nasal resistance has been amply discussed in literature, with controversies. Its skeletal and dental indications seem to be clear, however, those sole rhinologic are not justified, because positive results are not always found. This study had as purpose to evaluate the orthopedic rapid maxillary expansion repercussion on respiratory and rhinologic aspects of patients undergoing this procedure.

  20. Rapid evolution leads to differential population dynamics and top-down control in resurrectedDaphniapopulations.

    Science.gov (United States)

    Goitom, Eyerusalem; Kilsdonk, Laurens J; Brans, Kristien; Jansen, Mieke; Lemmens, Pieter; De Meester, Luc

    2018-01-01

    There is growing evidence of rapid genetic adaptation of natural populations to environmental change, opening the perspective that evolutionary trait change may subsequently impact ecological processes such as population dynamics, community composition, and ecosystem functioning. To study such eco-evolutionary feedbacks in natural populations, however, requires samples across time. Here, we capitalize on a resurrection ecology study that documented rapid and adaptive evolution in a natural population of the water flea Daphnia magna in response to strong changes in predation pressure by fish, and carry out a follow-up mesocosm experiment to test whether the observed genetic changes influence population dynamics and top-down control of phytoplankton. We inoculated populations of the water flea D. magna derived from three time periods of the same natural population known to have genetically adapted to changes in predation pressure in replicate mesocosms and monitored both Daphnia population densities and phytoplankton biomass in the presence and absence of fish. Our results revealed differences in population dynamics and top-down control of algae between mesocosms harboring populations from the time period before, during, and after a peak in fish predation pressure caused by human fish stocking. The differences, however, deviated from our a priori expectations. An S-map approach on time series revealed that the interactions between adults and juveniles strongly impacted the dynamics of populations and their top-down control on algae in the mesocosms, and that the strength of these interactions was modulated by rapid evolution as it occurred in nature. Our study provides an example of an evolutionary response that fundamentally alters the processes structuring population dynamics and impacts ecosystem features.

  1. CBCT of skeletal changes following rapid maxillary expansion to increase arch-length with a development-dependent bonded or banded appliance.

    Science.gov (United States)

    Kanomi, Ryuzo; Deguchi, Toru; Kakuno, Eriko; Takano-Yamamoto, Teruko; Roberts, W Eugene

    2013-09-01

    To assess the three-dimensional (3D) skeletal response to a standardized 5 mm of rapid maxillary expansion (RME) in growing children (6-15 years) with maxillary width deficiency and crowding. A bonded appliance was used prior to the eruption of the maxillary first premolars (Mx4s), and a banded appliance was used thereafter. A consecutive sample of 89 patients (29 boys and 60 girls) from a large pediatric dentistry and orthodontics practice was divided into four groups: 1) 6-8 years old (n = 26), 2) 9-11 years old with unerupted Mx4s (n = 21), 3) 9-11 years with erupted Mx4s (n = 23), and 4) 12-15 years (n = 19). For all patients, the 3D evaluation of dental and skeletal effects was performed with cone-beam computed tomography (CBCT). For both appliances in all patients, CBCT confirmed a triangular pattern of expansion in both the frontal and sagittal planes. Overall, both appliances produced significant maxillary expansion (>80% of the 5-mm activation), but older children showed a progressively more dental (less skeletal) response. Comparison of the two types of expanders in the crossover sample, children aged 9-11 years, showed that the bonded RME produced the most efficient skeletal expansion in the preadolescent sample. Increased maxillary width at the level of the zygomaticomaxillary suture was the best indicator for development of maxillary arch circumference. Development-dependent appliances (bonded RPE before Mx4s erupt, and a banded device thereafter) provided optimal RME treatment for all children from age 6-15 years.

  2. Rapid regulation of leaf photosynthesis, carbohydrate status and leaf area expansion to maintain growth in irregular light environments

    DEFF Research Database (Denmark)

    Kjær, Katrine Heinsvig

    2012-01-01

    to maintain carbohydrate status and growth in unpredictable light environments. Our recent results show rapid regulation of photosynthesis and leaf carbohydrate status to maintain growth and light interception in dynamic light environments when campanula, rose and chrysanthemum were grown in a cost...

  3. Educational expansion and inequalities in mortality-A fixed-effects analysis using longitudinal data from 18 European populations.

    Directory of Open Access Journals (Sweden)

    Olof Östergren

    Full Text Available The aim of this paper is to empirically evaluate whether widening educational inequalities in mortality are related to the substantive shifts that have occurred in the educational distribution.Data on education and mortality from 18 European populations across several decades were collected and harmonized as part of the Demetriq project. Using a fixed-effects approach to account for time trends and national variation in mortality, we formally test whether the magnitude of relative inequalities in mortality by education is associated with the gender and age-group specific proportion of high and low educated respectively.The results suggest that in populations with larger proportions of high educated and smaller proportions of low educated, the excess mortality among intermediate and low educated is larger, all other things being equal.We conclude that the widening educational inequalities in mortality being observed in recent decades may in part be attributed to educational expansion.

  4. Genetic consequences of population expansions and contractions in the common hippopotamus (Hippopotamus amphibius) since the Late Pleistocene

    DEFF Research Database (Denmark)

    Stoffel, Céline; Dufresnes, Christophe; Okello, John B A

    2015-01-01

    of semi-aquatic animals, which faced tremendous challenges imposed by unpredictable availability of water resources. In this study, we investigate the Late Pleistocene history of the common hippopotamus (Hippopotamus amphibius), using mitochondrial and nuclear DNA sequence variation and range......-wide sampling. We documented a global demographic and spatial expansion approximately 0.1-0.3 My ago, most likely associated with an episode of massive drainage overflow. These events presumably enabled a historical continent-wide gene flow among hippopotamus populations, and hence no clear continental......-scale genetic structuring remains. Nevertheless, present-day hippopotamus populations are genetically disconnected, probably as a result of the mid-Holocene aridification and contemporary anthropogenic pressures. This unique pattern contrasts with the biogeographic paradigms established for savannah...

  5. Range expansion and population dynamics of an invasive species: the Eurasian Collared-Dove (Streptopelia decaocto.

    Directory of Open Access Journals (Sweden)

    Spencer N Scheidt

    Full Text Available Invasive species offer ecologists the opportunity to study the factors governing species distributions and population growth. The Eurasian Collared-Dove (Streptopelia decaocto serves as a model organism for invasive spread because of the wealth of abundance records and the recent development of the invasion. We tested whether a set of environmental variables were related to the carrying capacities and growth rates of individual populations by modeling the growth trajectories of individual populations of the Collared-Dove using Breeding Bird Survey (BBS and Christmas Bird Count (CBC data. Depending on the fit of our growth models, carrying capacity and growth rate parameters were extracted and modeled using historical, geographical, land cover and climatic predictors. Model averaging and individual variable importance weights were used to assess the strength of these predictors. The specific variables with the greatest support in our models differed between data sets, which may be the result of temporal and spatial differences between the BBS and CBC. However, our results indicate that both carrying capacity and population growth rates are related to developed land cover and temperature, while growth rates may also be influenced by dispersal patterns along the invasion front. Model averaged multivariate models explained 35-48% and 41-46% of the variation in carrying capacities and population growth rates, respectively. Our results suggest that widespread species invasions can be evaluated within a predictable population ecology framework. Land cover and climate both have important effects on population growth rates and carrying capacities of Collared-Dove populations. Efforts to model aspects of population growth of this invasive species were more successful than attempts to model static abundance patterns, pointing to a potentially fruitful avenue for the development of improved invasive distribution models.

  6. The oriental fruit fly, Bactrocera dorsalis, in China: origin and gradual inland range expansion associated with population growth.

    Science.gov (United States)

    Wan, Xuanwu; Nardi, Francesco; Zhang, Bin; Liu, Yinghong

    2011-01-01

    The oriental fruit fly, Bactrocera dorsalis, expanded throughout mainland China in the last century to become one of the most serious pests in the area, yet information on this process are fragmentary. Three mitochondrial genes (nad1, cytb and nad5) were used to infer the genetic diversity, population structure and demographic history of the oriental fruit fly from its entire distribution range in China. High levels of genetic diversity, as well as a significant correspondence between genetic and geographic distances, suggest that the invasion process might have been gradual, with no associated genetic bottlenecks. Three population groups could be identified, nevertheless the overall genetic structure was weak. The effective number of migrants between populations, estimated using the coalescent method, suggested asymmetric gene flow from the costal region of Guangdong to most inland regions. The demographic analysis indicates the oriental fruit fly underwent a recent population expansion in the Central China. We suggest the species originated in the costal region facing the South China Sea and gradually expanded to colonize mainland China, expanding here to high population numbers.

  7. The ecology of population dispersal: Modeling alternative basin-plateau foraging strategies to explain the Numic expansion.

    Science.gov (United States)

    Magargal, Kate E; Parker, Ashley K; Vernon, Kenneth Blake; Rath, Will; Codding, Brian F

    2017-07-08

    The expansion of Numic speaking populations into the Great Basin required individuals to adapt to a relatively unproductive landscape. Researchers have proposed numerous social and subsistence strategies to explain how and why these settlers were able to replace any established populations, including private property and intensive plant processing. Here we evaluate these hypotheses and propose a new strategy involving the use of landscape fire to increase resource encounter rates. Implementing a novel, spatially explicit, multi-scalar prey choice model, we examine how individual decisions approximating each alternative strategy (private property, anthropogenic fire, and intensive plant processing) would aggregate at the patch and band level to confer an overall benefit to this colonizing population. Analysis relies on experimental data reporting resource profitability and abundance, ecological data on the historic distribution of vegetation patches, and ethnohistoric data on the distribution of Numic bands. Model results show that while resource privatization and landscape fires produce a substantial advantage, intensified plant processing garners the greatest benefit. The relative benefits of alternative strategies vary significantly across ecological patches resulting in variation across ethnographic band ranges. Combined, a Numic strategy including all three alternatives would substantially increase subsistence yields. The application of a strategy set that includes landscape fire, privatization and intensified processing of seeds and nuts, explains why the Numa were able to outcompete local populations. This approach provides a framework to help explain how individual decisions can result in such population replacement events throughout human history. © 2017 Wiley Periodicals, Inc.

  8. Signatures of recent directional selection under different models of population expansion during colonization of new selective environments.

    Science.gov (United States)

    Kim, Yuseob; Gulisija, Davorka

    2010-02-01

    A major problem in population genetics is understanding how the genomic pattern of polymorphism is shaped by natural selection and the demographic history of populations. Complex population dynamics confounds patterns of variation and poses serious challenges for identifying genomic imprints of selection. We examine patterns of polymorphism using computer simulations and provide analytical predictions for hitchhiking effects under two models of adaptive niche expansion. The population split (PS) model assumes the separation of a founding population followed by directional selection in the new environment. Here, the new population undergoes a bottleneck and later expands in size. This model has been used in previous studies to account for demographic effects when testing for signatures of selection under colonization or domestication. The genotype-dependent colonization and introgression (GDCI) model is proposed in this study and assumes that a small number of migrants carrying adaptive genotype found a new population, which then grows logistically. The GDCI model also allows for constant migration between the parental and the new population. Both models predict reduction in variation and excess of high frequency of derived alleles relative to neutral expectations, with and without hitchhiking. Under comparable conditions, the GDCI model results in greater reduction in expected heterozygosity and more skew of the site frequency spectrum than the PS model. We also find that soft selective sweeps (fixation of multiple copies of a beneficial mutation) occurs less often in the GDCI model than in the PS model. This result demonstrates the importance of correctly modeling the ecological process in inferring adaptive evolution using DNA sequence polymorphism.

  9. Is There Any Evidence for Rapid, Genetically-Based, Climatic Niche Expansion in the Invasive Common Ragweed?

    OpenAIRE

    Gallien, Laure; Thuiller, Wilfried; Fort, No?mie; Boleda, Marti; Alberto, Florian J.; Rioux, Delphine; Lain?, Juliette; Lavergne, S?bastien

    2016-01-01

    Climatic niche shifts have been documented in a number of invasive species by comparing the native and adventive climatic ranges in which they occur. However, these shifts likely represent changes in the realized climatic niches of invasive species, and may not necessarily be driven by genetic changes in climatic affinities. Until now the role of rapid niche evolution in the spread of invasive species remains a challenging issue with conflicting results. Here, we document a likely genetically...

  10. CTG expansion & haplotype analysis in DM1 gene in healthy Iranian population.

    Science.gov (United States)

    Shojasaffar, Bahareh; Moradin, Neda; Kahrizi, Kimia; Cobo, Ana Maria; Najmabadi, Hossein

    2008-05-01

    Myotonic dystrophy type 1 (DM1) is due to an unstable expansion of CTG repeat in the DMPK gene (19q13.3). The CTG repeat is highly polymorphic (5 to 37) in healthy individuals. According to the hypothesis that expanded (CTG)n alleles originated from larger normal alleles, there may exist a correlation between the prevalence of DM1 and the frequency of large size normal alleles. Strong linkage disequilibrium between different length alleles and the three biallelic markers, Alu, Hinf1 and Taq1, has been reported. To determine the distribution of normal alleles, the frequency of larger normal alleles and analysis of the three biallelic markers, in healthy Iranian controls. Polymerase chain reaction (PCR) was conducted on two hundred unrelated healthy individuals from different ethnic groups living in Iran to determine the size of the alleles. Markers were analyzed by PCR/RFLP on 174 chromosomes from other control healthy individuals. Our data reveals that 23.7% of alleles had 5 CTG repeats and 7.2% of alleles had > 18 CTG repeats. The analysis of haplotypes revealed that 75% of CTG5 and 80% of CTG > 18 had the (+++) haplotype. The frequency of alleles with CTG > 18 in Iran is similar to that of Western Europe and Japan.

  11. Population differentiation of southern Indian male lineages correlates with agricultural expansions predating the caste system.

    Directory of Open Access Journals (Sweden)

    Ganeshprasad Arunkumar

    Full Text Available Previous studies that pooled Indian populations from a wide variety of geographical locations, have obtained contradictory conclusions about the processes of the establishment of the Varna caste system and its genetic impact on the origins and demographic histories of Indian populations. To further investigate these questions we took advantage that both Y chromosome and caste designation are paternally inherited, and genotyped 1,680 Y chromosomes representing 12 tribal and 19 non-tribal (caste endogamous populations from the predominantly Dravidian-speaking Tamil Nadu state in the southernmost part of India. Tribes and castes were both characterized by an overwhelming proportion of putatively Indian autochthonous Y-chromosomal haplogroups (H-M69, F-M89, R1a1-M17, L1-M27, R2-M124, and C5-M356; 81% combined with a shared genetic heritage dating back to the late Pleistocene (10-30 Kya, suggesting that more recent Holocene migrations from western Eurasia contributed <20% of the male lineages. We found strong evidence for genetic structure, associated primarily with the current mode of subsistence. Coalescence analysis suggested that the social stratification was established 4-6 Kya and there was little admixture during the last 3 Kya, implying a minimal genetic impact of the Varna (caste system from the historically-documented Brahmin migrations into the area. In contrast, the overall Y-chromosomal patterns, the time depth of population diversifications and the period of differentiation were best explained by the emergence of agricultural technology in South Asia. These results highlight the utility of detailed local genetic studies within India, without prior assumptions about the importance of Varna rank status for population grouping, to obtain new insights into the relative influences of past demographic events for the population structure of the whole of modern India.

  12. Rapid Point-of-Care Diagnostic Test for Syphilis in High-Risk Populations, Manaus, Brazil

    Science.gov (United States)

    Benzaken, Adele S.; de Andrade Rodrigues, Ệnio José; Mayaud, Philippe

    2009-01-01

    We assessed the acceptability and operational suitability of a rapid point-of-care syphilis test and identified barriers to testing among high-risk groups and healthcare professionals in a sexually transmitted infections clinic in Manaus, Brazil. Use of this test could considerably alleviate the impact of syphilis in hard-to-reach populations in the Amazon region of Brazil. PMID:19331762

  13. A Pilot Study of Rapid Hepatitis C Testing in Probation and Parole Populations in Rhode Island.

    Science.gov (United States)

    Zaller, Nickolas D; Patry, Emily J; Bazerman, Lauri B; Noska, Amanda; Kuo, Irene; Kurth, Ann; Beckwith, Curt G

    2016-01-01

    Hepatitis C virus (HCV) affects between five and seven million individuals in the United States and chronic infection can lead to liver disease, cirrhosis, and hepatocellular carcinoma. Probation/parole offices are a novel setting for rapid HCV testing, providing outreach to populations at increased risk for HCV infection and/or transmitting HCV to others. While some correctional facilities offer HCV testing, many individuals who present to probation/parole offices are never or briefly incarcerated and may not access medical services. We conducted a rapid HCV testing pilot at probation/parole offices in Rhode Island. Overall, 130 people accepted rapid HCV testing, of whom 12 had reactive tests. Only four of these individuals presented to a community-based clinic for confirmatory testing, despite being offered a monetary incentive. Identifying and addressing barriers to HCV confirmatory testing and follow-up care is critical to increasing the uptake of HCV care and treatment in this vulnerable population.

  14. Clonal expansion of the Belgian Phytophthora ramorum populations based on new microsatellite markers

    Science.gov (United States)

    A. Vercauteren; I. De Dobbelaere; N. J. Grünwald; P. Bonants; E. Van Bockstaele; M. Maes; K. Heungens

    2010-01-01

    Co-existence of both mating types A1 and A2 within the EU1 lineage of Phytophthora ramorum has only been observed in Belgium, which begs the question whether sexual reproduction is occurring. A collection of 411 Belgian P. ramorum isolates was established during a 7-year survey. Our main objectives were genetic characterization of this population to test for sexual...

  15. Rapid declines of large mammal populations after the collapse of the Soviet Union.

    Science.gov (United States)

    Bragina, Eugenia V; Ives, A R; Pidgeon, A M; Kuemmerle, T; Baskin, L M; Gubar, Y P; Piquer-Rodríguez, M; Keuler, N S; Petrosyan, V G; Radeloff, V C

    2015-06-01

    Anecdotal evidence suggests that socioeconomic shocks strongly affect wildlife populations, but quantitative evidence is sparse. The collapse of socialism in Russia in 1991 caused a major socioeconomic shock, including a sharp increase in poverty. We analyzed population trends of 8 large mammals in Russia from 1981 to 2010 (i.e., before and after the collapse). We hypothesized that the collapse would first cause population declines, primarily due to overexploitation, and then population increases due to adaptation of wildlife to new environments following the collapse. The long-term Database of the Russian Federal Agency of Game Mammal Monitoring, consisting of up to 50,000 transects that are monitored annually, provided an exceptional data set for investigating these population trends. Three species showed strong declines in population growth rates in the decade following the collapse, while grey wolf (Canis lupus) increased by more than 150%. After 2000 some trends reversed. For example, roe deer (Capreolus spp.) abundance in 2010 was the highest of any period in our study. Likely reasons for the population declines in the 1990s include poaching and the erosion of wildlife protection enforcement. The rapid increase of the grey wolf populations is likely due to the cessation of governmental population control. In general, the widespread declines in wildlife populations after the collapse of the Soviet Union highlight the magnitude of the effects that socioeconomic shocks can have on wildlife populations and the possible need for special conservation efforts during such times. © 2015 Society for Conservation Biology.

  16. Strategic camouflage treatment of skeletal Class III malocclusion (mandibular prognathism) using bone-borne rapid maxillary expansion and mandibular anterior subapical osteotomy.

    Science.gov (United States)

    Seo, Yu-Jin; Lin, Lu; Kim, Seong-Hun; Chung, Kyu-Rhim; Nelson, Gerald

    2016-01-01

    This case report presents the camouflage treatment that successfully improved the facial profile of a patient with a skeletal Class III malocclusion using bone-borne rapid maxillary expansion and mandibular anterior subapical osteotomy. The patient was an 18-year-old woman with chief complaints of crooked teeth and a protruded jaw. Camouflage treatment was chosen because she rejected orthognathic surgery under general anesthesia. A hybrid type of bone-borne rapid maxillary expander with palatal mini-implants was used to correct the transverse discrepancy, and a mandibular anterior subapical osteotomy was conducted to achieve proper overjet with normal incisal inclination and to improve her lip and chin profile. As a result, a Class I occlusion with a favorable inclination of the anterior teeth and a good esthetic profile was achieved with no adverse effects. Therefore, the hybrid type of bone-borne rapid maxillary expander and a mandibular anterior subapical osteotomy can be considered effective camouflage treatment of a skeletal Class III malocclusion, providing improved inclination of the dentition and lip profile. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  17. Three Dimensional Finite Element Analysis of Stress Distribution and Displacement of the Maxilla Following Surgically Assisted Rapid Maxillary Expansion with Tooth- and Bone-Borne Devices

    Directory of Open Access Journals (Sweden)

    Mohsen Dalband

    2015-10-01

    Full Text Available Objectives: The aim of this study was to investigate the displacement and stress distri- bution during surgically assisted rapid maxillary expansion under different surgical conditions with tooth- and bone-borne devices.Materials and Methods: Three-dimensional (3D finite element model of a maxilla was constructed and an expansion force of 100 N was applied to the left and right molars and premolars with tooth-borne devices and the left and right of mid-palatal sutures at the first molar level with bone-borne devices. Five CAD models were simulated as fol- lows and surgical procedures were used:  G1: control group (without surgery; G2: Le Fort I osteotomy; G3: Le Fort I osteotomy and para-median osteotomy; G4: Le Fort I osteotomy and pterygomaxillary separation; and G5: Le Fort I osteotomy, para-median osteotomy, and pterygomaxillary separation.Results: Maxillary displacement showed a gradual increase from group 1 to group 5 in all three planes of space, indicating that Le Fort I osteotomy combined with para-me- dian osteotomy and pterygomaxillary separation produced the greatest displacement of the maxilla with both bone- and tooth-borne devices. Surgical relief and bone-borne devices resulted in significantly reduced stress on anchored teeth.Conclusion: Combination of Le Fort I and para-median osteotomy with pterygomaxil-lary separation seems to be an effective procedure for increasing maxillary expansion, and excessive stress side effects are lowered around the anchored teeth with the use of bone-borne devices.

  18. Conclusions about Niche Expansion in Introduced Impatiens walleriana Populations Depend on Method of Analysis

    OpenAIRE

    Mandle, Lisa; Warren, Dan L.; Hoffmann, Matthias H.; Peterson, A. Townsend; Schmitt, Johanna; von Wettberg, Eric J.

    2010-01-01

    Determining the degree to which climate niches are conserved across plant species' native and introduced ranges is valuable to developing successful strategies to limit the introduction and spread of invasive plants, and also has important ecological and evolutionary implications. Here, we test whether climate niches differ between native and introduced populations of Impatiens walleriana, globally one of the most popular horticultural species. We use approaches based on both raw climate data...

  19. Algebraic Reynolds stress modeling of turbulence subject to rapid homogeneous and non-homogeneous compression or expansion

    Science.gov (United States)

    Grigoriev, I. A.; Wallin, S.; Brethouwer, G.; Grundestam, O.; Johansson, A. V.

    2016-02-01

    A recently developed explicit algebraic Reynolds stress model (EARSM) by Grigoriev et al. ["A realizable explicit algebraic Reynolds stress model for compressible turbulent flow with significant mean dilatation," Phys. Fluids 25(10), 105112 (2013)] and the related differential Reynolds stress model (DRSM) are used to investigate the influence of homogeneous shear and compression on the evolution of turbulence in the limit of rapid distortion theory (RDT). The DRSM predictions of the turbulence kinetic energy evolution are in reasonable agreement with RDT while the evolution of diagonal components of anisotropy correctly captures the essential features, which is not the case for standard compressible extensions of DRSMs. The EARSM is shown to give a realizable anisotropy tensor and a correct trend of the growth of turbulence kinetic energy K, which saturates at a power law growth versus compression ratio, as well as retaining a normalized strain in the RDT regime. In contrast, an eddy-viscosity model results in a rapid exponential growth of K and excludes both realizability and high magnitude of the strain rate. We illustrate the importance of using a proper algebraic treatment of EARSM in systems with high values of dilatation and vorticity but low shear. A homogeneously compressed and rotating gas cloud with cylindrical symmetry, related to astrophysical flows and swirling supercritical flows, was investigated too. We also outline the extension of DRSM and EARSM to include the effect of non-homogeneous density coupled with "local mean acceleration" which can be important for, e.g., stratified flows or flows with heat release. A fixed-point analysis of direct numerical simulation data of combustion in a wall-jet flow demonstrates that our model gives quantitatively correct predictions of both streamwise and cross-stream components of turbulent density flux as well as their influence on the anisotropies. In summary, we believe that our approach, based on a proper

  20. Dental arch response to Haas-type rapid maxillary expansion anchored to deciduous vs permanent molars: A multicentric randomized controlled trial.

    Science.gov (United States)

    Ugolini, Alessandro; Cerruto, Carmen; Di Vece, Luca; Ghislanzoni, Luis Huanca; Sforza, Chiarella; Doldo, Tiziana; Silvestrini-Biavati, Armando; Caprioglio, Alberto

    2015-07-01

    To assess maxilla and mandibular arch widths' response to Haas-type rapid maxillary expansion (RME) anchored to deciduous vs permanent molars on children with unilateral posterior crossbite. Seventy patients with unilateral posterior crossbite recruited at the Universities of Genova, Siena, and Insubria (Varese) were randomly located into GrE (RME on second deciduous molars) or Gr6 (RME on first permanent molars) and compared. Upper intermolar distance and permanent molar angulation increased significantly in Gr6 vs GrE at T1. Upper intercanine distance increased significantly in GrE vs Gr6 at T1 and T2. GrE showed significant increases for upper intermolar and upper intercanine widths. Gr6 showed statistically significant increases for upper intermolar widths, for upper and lower intercanine widths, and for increases of angulation of upper and lower permanent molars. GrE showed reduced molar angulation increases at T1 and reduced molar angulation decreases at T2 when compared with Gr6. At T2, the net increase of the upper intercanine distance in GrE was still significant compared with Gr6, indicating a more stable expansion in the anterior area.

  1. Craniofacial and upper airway morphology in pediatric sleep-disordered breathing and changes in quality of life with rapid maxillary expansion.

    Science.gov (United States)

    Katyal, Vandana; Pamula, Yvonne; Daynes, Cathal N; Martin, James; Dreyer, Craig W; Kennedy, Declan; Sampson, Wayne J

    2013-12-01

    The association between pediatric sleep-disordered breathing caused by upper airway obstruction and craniofacial morphology is poorly understood and contradictory. The aims of this study were to evaluate the prevalence of children at risk for sleep-disordered breathing, as identified in an orthodontic setting by validated screening questionnaires, and to examine associations with their craniofacial and upper airway morphologies. A further aim was to assess the change in quality of life related to sleep-disordered breathing for affected children undergoing rapid maxillary expansion to correct a palatal crossbite or widen a narrow maxilla. A prospective case-control study with children between 8 and 17 years of age (n = 81) at an orthodontic clinic was undertaken. The subjects were grouped as high risk or low risk for sleep-disordered breathing based on the scores from a validated 22-item Pediatric Sleep Questionnaire and the Obstructive Sleep Apnea-18 Quality of Life Questionnaire. Variables pertaining to a screening clinical examination, cephalometric assessment, and dental cast analysis were tested for differences between the 2 groups at baseline. Ten children who underwent rapid maxillary expansion were followed longitudinally until removal of the appliance approximately 9 months later with a repeated Obstructive Sleep Apnea-18 Quality of Life Questionnaire. All data were collected blinded to the questionnaire results. The frequency of palatal crossbite involving at least 3 teeth was significantly higher in the high-risk group at 68.2%, compared with the low-risk group at 23.2% (P children in the low-risk group at baseline (P maxillary intercanine, maxillary interfirst premolar, maxillary interfirst molar, mandibular intercanine, and mandibular interfirst premolar widths were reduced in the high-risk group compared with the low-risk group by 4.22 mm (P Children treated with rapid maxillary expansion showed an average improvement of 14% in quality of life

  2. Rapid population growth. Effects on the social infrastructures of southern Africa.

    Science.gov (United States)

    Smith, J D

    1995-01-01

    Southern Africa's high rate of population growth and widespread poverty have serious implications for the region's social infrastructure. Large increases in the school-age population have undermined efforts to improve the quality of education since all resources are directed toward expansion of availability. To achieve a teacher-pupil ratio of 1:40 at the primary level and 1:35 at the secondary level, an estimated additional 50,000 classrooms would be required. Also jeopardized by high fertility is access to health services, safe water, and sanitation. In Mozambique, for example, where only 30% of the population has access to health services, the under-five years mortality rate is 297/1000 live births and the physician-population ratio is 1:37,970. Substandard housing, homelessness, congestion, deteriorating public services, pollution, and crime dominate urban areas. The single most effective intervention to reduce population growth in Southern Africa is female education. Women without a secondary education bear an average of seven children; if 40% of women attend secondary school, this drops to three children. Thus, governments must make gender equality a central focus of development planning and ensure that women are participants in this process. Property and inheritance laws that serve to increase the economic need for early marriage should be eliminated. Public health programs, including family planning, must be expanded. Finally, women's organizations should be strengthened and urged to foster female empowerment.

  3. Voluntary Medical Male Circumcision: Translating Research into the Rapid Expansion of Services in Kenya, 2008–2011

    Science.gov (United States)

    Mwandi, Zebedee; Murphy, Anne; Reed, Jason; Chesang, Kipruto; Njeuhmeli, Emmanuel; Agot, Kawango; Llewellyn, Emma; Kirui, Charles; Serrem, Kennedy; Abuya, Isaac; Loolpapit, Mores; Mbayaki, Regina; Kiriro, Ndungu; Cherutich, Peter; Muraguri, Nicholas; Motoku, John; Kioko, Jack; Knight, Nancy; Bock, Naomi

    2011-01-01

    Since the World Health Organization and the Joint United Nations Programme on HIV/AIDS recommended implementation of medical male circumcision (MC) as part of HIV prevention in areas with low MC and high HIV prevalence rates in 2007, the government of Kenya has developed a strategy to circumcise 80% of uncircumcised men within five years. To facilitate the quick translation of research to practice, a national MC task force was formed in 2007, a medical MC policy was implemented in early 2008, and Nyanza Province, the region with the highest HIV burden and low rates of circumcision, was prioritized for services under the direction of a provincial voluntary medical male circumcision (VMMC) task force. The government's early and continuous engagement with community leaders/elders, politicians, youth, and women's groups has led to the rapid endorsement and acceptance of VMMC. In addition, several innovative approaches have helped to optimize VMMC scale-up. Since October 2008, the Kenyan VMMC program has circumcised approximately 290,000 men, mainly in Nyanza Province, an accomplishment made possible through a combination of governmental leadership, a documented implementation strategy, and the adoption of appropriate and innovative approaches. Kenya's success provides a model for others planning VMMC scale-up programs. PMID:22140365

  4. Voluntary medical male circumcision: translating research into the rapid expansion of services in Kenya, 2008-2011.

    Directory of Open Access Journals (Sweden)

    Zebedee Mwandi

    2011-11-01

    Full Text Available Since the World Health Organization and the Joint United Nations Programme on HIV/AIDS recommended implementation of medical male circumcision (MC as part of HIV prevention in areas with low MC and high HIV prevalence rates in 2007, the government of Kenya has developed a strategy to circumcise 80% of uncircumcised men within five years. To facilitate the quick translation of research to practice, a national MC task force was formed in 2007, a medical MC policy was implemented in early 2008, and Nyanza Province, the region with the highest HIV burden and low rates of circumcision, was prioritized for services under the direction of a provincial voluntary medical male circumcision (VMMC task force. The government's early and continuous engagement with community leaders/elders, politicians, youth, and women's groups has led to the rapid endorsement and acceptance of VMMC. In addition, several innovative approaches have helped to optimize VMMC scale-up. Since October 2008, the Kenyan VMMC program has circumcised approximately 290,000 men, mainly in Nyanza Province, an accomplishment made possible through a combination of governmental leadership, a documented implementation strategy, and the adoption of appropriate and innovative approaches. Kenya's success provides a model for others planning VMMC scale-up programs.

  5. Antioxidants cause rapid expansion of human adipose-derived mesenchymal stem cells via CDK and CDK inhibitor regulation

    Science.gov (United States)

    2013-01-01

    Background Antioxidants have been shown to enhance the proliferation of adipose-derived mesenchymal stem cells (ADMSCs) in vitro, although the detailed mechanism(s) and potential side effects are not fully understood. In this study, human ADMSCs cultured in ImF-A medium supplemented with antioxidants (N-acetyl-l-cysteine and ascorbic acid-2-phosphate) and fibroblast growth factor 2 (FGF-2) were compared with ADMSCs cultured with FGF-2 alone (ImF) or with FGF-2 under 5% pO2 conditions (ImF-H). Results During log-phase growth, exposure to ImF-A resulted in a higher percentage of ADMSCs in the S phase of the cell cycle and a smaller percentage in G0/G1 phase. This resulted in a significantly reduced cell-doubling time and increased number of cells in the antioxidant-supplemented cultures compared with those supplemented with FGF-2 alone, an approximately 225% higher cell density after 7 days. Western blotting showed that the levels of the CDK inhibitors p21 and p27 decreased after ImF-A treatment, whereas CDK2, CDK4, and CDC2 levels clearly increased. In addition, ImF-A resulted in significant reduction in the expression of CD29, CD90, and CD105, whereas relative telomere length, osteogenesis, adipogenesis, and chondrogenesis were enhanced. The results were similar for ADMSCs treated with antioxidants and those under hypoxic conditions. Conclusion Antioxidant treatment promotes entry of ADMSCs into the S phase by suppressing cyclin-dependent kinase inhibitors and results in rapid cell proliferation similar to that observed under hypoxic conditions. PMID:23915242

  6. Divergence patterns of genic copy number variation in natural populations of the house mouse (Mus musculus domesticus) reveal three conserved genes with major population-specific expansions.

    Science.gov (United States)

    Pezer, Željka; Harr, Bettina; Teschke, Meike; Babiker, Hiba; Tautz, Diethard

    2015-08-01

    Copy number variation represents a major source of genetic divergence, yet the evolutionary dynamics of genic copy number variation in natural populations during differentiation and adaptation remain unclear. We applied a read depth approach to genome resequencing data to detect copy number variants (CNVs) ≥1 kb in wild-caught mice belonging to four populations of Mus musculus domesticus. We complemented the bioinformatics analyses with experimental validation using droplet digital PCR. The specific focus of our analysis is CNVs that include complete genes, as these CNVs could be expected to contribute most directly to evolutionary divergence. In total, 1863 transcription units appear to be completely encompassed within CNVs in at least one individual when compared to the reference assembly. Further, 179 of these CNVs show population-specific copy number differences, and 325 are subject to complete deletion in multiple individuals. Among the most copy-number variable genes are three highly conserved genes that encode the splicing factor CWC22, the spindle protein SFI1, and the Holliday junction recognition protein HJURP. These genes exhibit population-specific expansion patterns that suggest involvement in local adaptations. We found that genes that overlap with large segmental duplications are generally more copy-number variable. These genes encode proteins that are relevant for environmental and behavioral interactions, such as vomeronasal and olfactory receptors, as well as major urinary proteins and several proteins of unknown function. The overall analysis shows that genic CNVs contribute more to population differentiation in mice than in humans and may promote and speed up population divergence. © 2015 Pezer et al.; Published by Cold Spring Harbor Laboratory Press.

  7. Establishment of a coastal fish in the Azores: recent colonisation or sudden expansion of an ancient relict population?

    Science.gov (United States)

    Stefanni, S; Castilho, R; Sala-Bozano, M; Robalo, J I; Francisco, S M; Santos, R S; Marques, N; Brito, A; Almada, V C; Mariani, S

    2015-12-01

    The processes and timescales associated with ocean-wide changes in the distribution of marine species have intrigued biologists since Darwin's earliest insights into biogeography. The Azores, a mid-Atlantic volcanic archipelago located >1000 km off the European continental shelf, offers ideal opportunities to investigate phylogeographic colonisation scenarios. The benthopelagic sparid fish known as the common two-banded seabream (Diplodus vulgaris) is now relatively common along the coastline of the Azores archipelago, but was virtually absent before the 1990 s. We employed a multiple genetic marker approach to test whether the successful establishment of the Azorean population derives from a recent colonisation from western continental/island populations or from the demographic explosion of an ancient relict population. Results from nuclear and mtDNA sequences show that all Atlantic and Mediterranean populations belong to the same phylogroup, though microsatellite data indicate significant genetic divergence between the Azorean sample and all other locations, as well as among Macaronesian, western Iberian and Mediterranean regions. The results from Approximate Bayesian Computation indicate that D. vulgaris has likely inhabited the Azores for ∼ 40 (95% confidence interval (CI): 5.5-83.6) to 52 (95% CI: 6.32-89.0) generations, corresponding to roughly 80-150 years, suggesting near-contemporary colonisation, followed by a more recent demographic expansion that could have been facilitated by changing climate conditions. Moreover, the lack of previous records of this species over the past century, together with the absence of lineage separation and the presence of relatively few private alleles, do not exclude the possibility of an even more recent colonisation event.

  8. Cigarette smoke promotes drug resistance and expansion of cancer stem cell-like side population.

    Science.gov (United States)

    An, Yi; Kiang, Alan; Lopez, Jay Patrick; Kuo, Selena Z; Yu, Michael Andrew; Abhold, Eric L; Chen, Jocelyn S; Wang-Rodriguez, Jessica; Ongkeko, Weg M

    2012-01-01

    It is well known that many patients continue to smoke cigarettes after being diagnosed with cancer. Although smoking cessation has typically been presumed to possess little therapeutic value for cancer, a growing body of evidence suggests that continued smoking is associated with reduced efficacy of treatment and a higher incidence of recurrence. We therefore investigated the effect of cigarette smoke condensate (CSC) on drug resistance in the lung cancer and head and neck cancer cell lines A549 and UMSCC-10B, respectively. Our results showed that CSC significantly increased the cellular efflux of doxorubicin and mitoxantrone. This was accompanied by membrane localization and increased expression of the multi-drug transporter ABCG2. The induced efflux of doxorubicin was reversed upon addition of the specific ABCG2 inhibitor Fumitremorgin C, confirming the role of ABCG2. Treatment with CSC increased the concentration of phosphorylated Akt, while addition of the PI3K inhibitor LY294002 blocked doxorubicin extrusion, suggesting that Akt activation is required for CSC-induced drug efflux. In addition, CSC was found to promote resistance to doxorubicin as determined by MTS assays. This CSC-induced doxurbicin-resistance was mitigated by mecamylamine, a nicotinic acetylcholine receptor inhibitor, suggesting that nicotine is at least partially responsible for the effect of CSC. Lastly, CSC increased the size of the side population (SP), which has been linked to a cancer stem cell-like phenotype. In summary, CSC promotes chemoresistance via Akt-mediated regulation of ABCG2 activity, and may also increase the proportion of cancer stem-like cells, contributing to tumor resilience. These findings underscore the importance of smoking cessation following a diagnosis of cancer, and elucidate the mechanisms of continued smoking that may be detrimental to treatment.

  9. Cigarette smoke promotes drug resistance and expansion of cancer stem cell-like side population.

    Directory of Open Access Journals (Sweden)

    Yi An

    Full Text Available It is well known that many patients continue to smoke cigarettes after being diagnosed with cancer. Although smoking cessation has typically been presumed to possess little therapeutic value for cancer, a growing body of evidence suggests that continued smoking is associated with reduced efficacy of treatment and a higher incidence of recurrence. We therefore investigated the effect of cigarette smoke condensate (CSC on drug resistance in the lung cancer and head and neck cancer cell lines A549 and UMSCC-10B, respectively. Our results showed that CSC significantly increased the cellular efflux of doxorubicin and mitoxantrone. This was accompanied by membrane localization and increased expression of the multi-drug transporter ABCG2. The induced efflux of doxorubicin was reversed upon addition of the specific ABCG2 inhibitor Fumitremorgin C, confirming the role of ABCG2. Treatment with CSC increased the concentration of phosphorylated Akt, while addition of the PI3K inhibitor LY294002 blocked doxorubicin extrusion, suggesting that Akt activation is required for CSC-induced drug efflux. In addition, CSC was found to promote resistance to doxorubicin as determined by MTS assays. This CSC-induced doxurbicin-resistance was mitigated by mecamylamine, a nicotinic acetylcholine receptor inhibitor, suggesting that nicotine is at least partially responsible for the effect of CSC. Lastly, CSC increased the size of the side population (SP, which has been linked to a cancer stem cell-like phenotype. In summary, CSC promotes chemoresistance via Akt-mediated regulation of ABCG2 activity, and may also increase the proportion of cancer stem-like cells, contributing to tumor resilience. These findings underscore the importance of smoking cessation following a diagnosis of cancer, and elucidate the mechanisms of continued smoking that may be detrimental to treatment.

  10. Rapid Gene Turnover as a Significant Source of Genetic Variation in a Recently Seeded Population of a Healthcare-Associated Pathogen

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    Lucía Graña-Miraglia

    2017-09-01

    Full Text Available Genome sequencing has been useful to gain an understanding of bacterial evolution. It has been used for studying the phylogeography and/or the impact of mutation and recombination on bacterial populations. However, it has rarely been used to study gene turnover at microevolutionary scales. Here, we sequenced Mexican strains of the human pathogen Acinetobacter baumannii sampled from the same locale over a 3 year period to obtain insights into the microevolutionary dynamics of gene content variability. We found that the Mexican A. baumannii population was recently founded and has been emerging due to a rapid clonal expansion. Furthermore, we noticed that on average the Mexican strains differed from each other by over 300 genes and, notably, this gene content variation has accrued more frequently and faster than the accumulation of mutations. Moreover, due to its rapid pace, gene content variation reflects the phylogeny only at very short periods of time. Additionally, we found that the external branches of the phylogeny had almost 100 more genes than the internal branches. All in all, these results show that rapid gene turnover has been of paramount importance in producing genetic variation within this population and demonstrate the utility of genome sequencing to study alternative forms of genetic variation.

  11. Rapid Gene Turnover as a Significant Source of Genetic Variation in a Recently Seeded Population of a Healthcare-Associated Pathogen.

    Science.gov (United States)

    Graña-Miraglia, Lucía; Lozano, Luis F; Velázquez, Consuelo; Volkow-Fernández, Patricia; Pérez-Oseguera, Ángeles; Cevallos, Miguel A; Castillo-Ramírez, Santiago

    2017-01-01

    Genome sequencing has been useful to gain an understanding of bacterial evolution. It has been used for studying the phylogeography and/or the impact of mutation and recombination on bacterial populations. However, it has rarely been used to study gene turnover at microevolutionary scales. Here, we sequenced Mexican strains of the human pathogen Acinetobacter baumannii sampled from the same locale over a 3 year period to obtain insights into the microevolutionary dynamics of gene content variability. We found that the Mexican A. baumannii population was recently founded and has been emerging due to a rapid clonal expansion. Furthermore, we noticed that on average the Mexican strains differed from each other by over 300 genes and, notably, this gene content variation has accrued more frequently and faster than the accumulation of mutations. Moreover, due to its rapid pace, gene content variation reflects the phylogeny only at very short periods of time. Additionally, we found that the external branches of the phylogeny had almost 100 more genes than the internal branches. All in all, these results show that rapid gene turnover has been of paramount importance in producing genetic variation within this population and demonstrate the utility of genome sequencing to study alternative forms of genetic variation.

  12. Miocene and Pliocene dominated diversification of the lichen-forming fungal genus Melanohalea (Parmeliaceae, Ascomycota) and Pleistocene population expansions.

    Science.gov (United States)

    Leavitt, Steven D; Esslinger, Theodore L; Divakar, Pradeep K; Lumbsch, H Thorsten

    2012-09-11

    Factors promoting diversification in lichen symbioses remain largely unexplored. While Pleistocene events have been important for driving diversification and affecting distributions in many groups, recent estimates suggest that major radiations within some genera in the largest clade of macrolichens (Parmeliaceae, Ascomycota) vastly predate the Pleistocene. To better understand the temporal placement and sequence of diversification events in lichens, we estimated divergence times in a common lichen-forming fungal genus, Melanohalea, in the Northern Hemisphere. Divergence times were estimated using both concatenated gene tree and coalescent-based multilocus species tree approaches to assess the temporal context of major radiation events within Melanohalea. In order to complement our understanding of processes impacting genetic differentiation, we also evaluated the effects of Pleistocene glacial cycles on population demographics of distinct Melanohalea lineages, differing in reproductive strategies. We found that divergence estimates, from both concatenated gene tree and coalescent-based multilocus species tree approaches, suggest that diversification within Melanohalea occurred predominantly during the Miocene and Pliocene, although estimated of divergence times differed by up to 8.3 million years between the two methods. These results indicate that, in some cases, taxonomically diagnostic characters may be maintained among divergent lineages for millions of years. In other cases, similar phenotypic characters among non-sister taxa, including reproductive strategies, suggest the potential for convergent evolution due to similar selective pressures among distinct lineages. Our analyses provide evidence of population expansions predating the last glacial maximum in the sampled lineages. These results suggest that Pleistocene glaciations were not inherently unfavorable or restrictive for some Melanohalea species, albeit with apparently different demographic histories

  13. Miocene and Pliocene dominated diversification of the lichen-forming fungal genus Melanohalea (Parmeliaceae, Ascomycota and Pleistocene population expansions

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    Leavitt Steven D

    2012-09-01

    Full Text Available Abstract Background Factors promoting diversification in lichen symbioses remain largely unexplored. While Pleistocene events have been important for driving diversification and affecting distributions in many groups, recent estimates suggest that major radiations within some genera in the largest clade of macrolichens (Parmeliaceae, Ascomycota vastly predate the Pleistocene. To better understand the temporal placement and sequence of diversification events in lichens, we estimated divergence times in a common lichen-forming fungal genus, Melanohalea, in the Northern Hemisphere. Divergence times were estimated using both concatenated gene tree and coalescent-based multilocus species tree approaches to assess the temporal context of major radiation events within Melanohalea. In order to complement our understanding of processes impacting genetic differentiation, we also evaluated the effects of Pleistocene glacial cycles on population demographics of distinct Melanohalea lineages, differing in reproductive strategies. Results We found that divergence estimates, from both concatenated gene tree and coalescent-based multilocus species tree approaches, suggest that diversification within Melanohalea occurred predominantly during the Miocene and Pliocene, although estimated of divergence times differed by up to 8.3 million years between the two methods. These results indicate that, in some cases, taxonomically diagnostic characters may be maintained among divergent lineages for millions of years. In other cases, similar phenotypic characters among non-sister taxa, including reproductive strategies, suggest the potential for convergent evolution due to similar selective pressures among distinct lineages. Our analyses provide evidence of population expansions predating the last glacial maximum in the sampled lineages. These results suggest that Pleistocene glaciations were not inherently unfavorable or restrictive for some Melanohalea species, albeit

  14. Mixed Fortunes: Ancient Expansion and Recent Decline in Population Size of a Subtropical Montane Primate, the Arunachal Macaque Macaca munzala

    Science.gov (United States)

    Chakraborty, Debapriyo; Sinha, Anindya; Ramakrishnan, Uma

    2014-01-01

    Quaternary glacial oscillations are known to have caused population size fluctuations in many temperate species. Species from subtropical and tropical regions are, however, considerably less studied, despite representing most of the biodiversity hotspots in the world including many highly threatened by anthropogenic activities such as hunting. These regions, consequently, pose a significant knowledge gap in terms of how their fauna have typically responded to past climatic changes. We studied an endangered primate, the Arunachal macaque Macaca munzala, from the subtropical southern edge of the Tibetan plateau, a part of the Eastern Himalaya biodiversity hotspot, also known to be highly threatened due to rampant hunting. We employed a 534 bp-long mitochondrial DNA sequence and 22 autosomal microsatellite loci to investigate the factors that have potentially shaped the demographic history of the species. Analysing the genetic data with traditional statistical methods and advance Bayesian inferential approaches, we demonstrate a limited effect of past glacial fluctuations on the demographic history of the species before the last glacial maximum, approximately 20,000 years ago. This was, however, immediately followed by a significant population expansion possibly due to warmer climatic conditions, approximately 15,000 years ago. These changes may thus represent an apparent balance between that displayed by the relatively climatically stable tropics and those of the more severe, temperate environments of the past. This study also draws attention to the possibility that a cold-tolerant species like the Arunachal macaque, which could withstand historical climate fluctuations and grow once the climate became conducive, may actually be extremely vulnerable to anthropogenic exploitation, as is perhaps indicated by its Holocene ca. 30-fold population decline, approximately 3,500 years ago. Our study thus provides a quantitative appraisal of these demographically important

  15. Alterações na dimensão transversal pela expansão rápida da maxila Transverse dimension alterations using rapid maxillary expansion

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    Roberto M. A. Lima Filho

    2009-10-01

    Full Text Available As deformidades transversais, que se manifestam tipicamente pela mordida cruzada unilateral ou bilateral, são os problemas esqueléticos que mais sequelas podem causar na região craniofacial. Entretanto, são as deformidades que melhor se adaptam às alterações ortopédicas. A expansão rápida da maxila tornou-se rotina na prática ortodôntica. Embora inicialmente tenha sido utilizada na correção da mordida cruzada posterior, atualmente sua indicação ampliou-se para a expansão indireta do arco inferior, obtenção de espaço para correção de apinhamento dentário, correção axial dos dentes posteriores, melhora na estética do sorriso e auxílio no tratamento de pacientes Classe II. A expansão ortopédica da maxila vem atraindo cada vez mais a atenção da comunidade científica devido, principalmente, à sua aplicação e capacidade de alterar o crescimento craniofacial em diversas situações clínicas. Esse tipo de intervenção ortopédica possui grande utilidade terapêutica, pois sua aplicação em diversas anormalidades apresenta maior versatilidade quando comparada aos aparelhos de modificação de crescimento disponíveis atualmente para o tratamento ortodôntico.Transverse deformities, typically manifested by unilateral or bilateral crossbite, are the skeletal problems that can cause more sequels in the craniofacial region. However, such deformities are the most adaptable to orthopedic changes. Rapid maxillary expansion has become a routine in the orthodontic practice. Even though initially such procedure has been used for correction of posterior crossbite, today it has been applied for indirect expansion of the lower arch, obtaining space for correction of dental crowding, correction of axial inclination of posterior teeth, improvement in the smile aesthetics characteristics and on treatment of Class II patients. Orthopedic maxillary expansion has gained increasing attention of the scientific community due to its

  16. Galaxy Zoo: evidence for rapid, recent quenching within a population of AGN host galaxies

    Science.gov (United States)

    Smethurst, R. J.; Lintott, C. J.; Simmons, B. D.; Schawinski, K.; Bamford, S. P.; Cardamone, C. N.; Kruk, S. J.; Masters, K. L.; Urry, C. M.; Willett, K. W.; Wong, O. I.

    2016-12-01

    We present a population study of the star formation history of 1244 Type 2 active galactic nuclei (AGN) host galaxies, compared to 6107 inactive galaxies. A Bayesian method is used to determine individual galaxy star formation histories, which are then collated to visualize the distribution for quenching and quenched galaxies within each population. We find evidence for some of the Type 2 AGN host galaxies having undergone a rapid drop in their star formation rate within the last 2 Gyr. AGN feedback is therefore important at least for this population of galaxies. This result is not seen for the quenching and quenched inactive galaxies whose star formation histories are dominated by the effects of downsizing at earlier epochs, a secondary effect for the AGN host galaxies. We show that histories of rapid quenching cannot account fully for the quenching of all the star formation in a galaxy's lifetime across the population of quenched AGN host galaxies, and that histories of slower quenching, attributed to secular (non-violent) evolution, are also key in their evolution. This is in agreement with recent results showing that both merger-driven and non-merger processes are contributing to the co-evolution of galaxies and supermassive black holes. The availability of gas in the reservoirs of a galaxy, and its ability to be replenished, appear to be the key drivers behind this co-evolution.

  17. Six rapid assessments of alcohol and other substance use in populations displaced by conflict

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    Adelekan Moruf

    2011-02-01

    Full Text Available Abstract Background Substance use among populations displaced by conflict is a neglected area of public health. Alcohol, khat, benzodiazepine, opiate, and other substance use have been documented among a range of displaced populations, with wide-reaching health and social impacts. Changing agendas in humanitarian response-including increased prominence of mental health and chronic illness-have so far failed to be translated into meaningful interventions for substance use. Methods Studies were conducted from 2006 to 2008 in six different settings of protracted displacement, three in Africa (Kenya, Liberia, northern Uganda and three in Asia (Iran, Pakistan, and Thailand. We used intervention-oriented qualitative Rapid Assessment and Response methods, adapted from two decades of experience among non-displaced populations. The main sources of data were individual and group interviews conducted with a culturally representative (non-probabilistic sample of community members and service providers. Results Widespread use of alcohol, particularly artisanally-produced alcohol, in Kenya, Liberia, Uganda, and Thailand, and opiates in Iran and Pakistan was believed by participants to be linked to a range of health, social and protection problems, including illness, injury (intentional and unintentional, gender-based violence, risky behaviour for HIV and other sexually transmitted infection and blood-borne virus transmission, as well as detrimental effects to household economy. Displacement experiences, including dispossession, livelihood restriction, hopelessness and uncertain future may make communities particularly vulnerable to substance use and its impact, and changing social norms and networks (including the surrounding population may result in changed - and potentially more harmful-patterns of use. Limited access to services, including health services, and exclusion from relevant host population programmes, may exacerbate the harmful consequences

  18. The population genomics of rapid adaptation: disentangling signatures of selection and demography in white sands lizards.

    Science.gov (United States)

    Laurent, Stefan; Pfeifer, Susanne P; Settles, Matthew L; Hunter, Samuel S; Hardwick, Kayla M; Ormond, Louise; Sousa, Vitor C; Jensen, Jeffrey D; Rosenblum, Erica Bree

    2016-01-01

    Understanding the process of adaptation during rapid environmental change remains one of the central focal points of evolutionary biology. The recently formed White Sands system of southern New Mexico offers an outstanding example of rapid adaptation, with a variety of species having rapidly evolved blanched forms on the dunes that contrast with their close relatives in the surrounding dark soil habitat. In this study, we focus on two of the White Sands lizard species, Sceloporus cowlesi and Aspidoscelis inornata, for which previous research has linked mutations in the melanocortin-1 receptor gene (Mc1r) to blanched coloration. We sampled populations both on and off the dunes and used a custom sequence capture assay based on probed fosmid libraries to obtain >50 kb of sequence around Mc1r and hundreds of other random genomic locations. We then used model-based statistical inference methods to describe the demographic and adaptive history characterizing the colonization of White Sands. We identified a number of similarities between the two focal species, including strong evidence of selection in the blanched populations in the Mc1r region. We also found important differences between the species, suggesting different colonization times, different genetic architecture underlying the blanched phenotype and different ages of the beneficial alleles. Finally, the beneficial allele is dominant in S. cowlesi and recessive in A. inornata, allowing for a rare empirical test of theoretically expected patterns of selective sweeps under these differing models. © 2015 John Wiley & Sons Ltd.

  19. Testing the influence of climate, human impact and fire on the Holocene population expansion of Fagus sylvatica in the southern Prealps (Italy)

    NARCIS (Netherlands)

    Valsecchi, V.; Finsinger, W.; Tinner, W.; Ammann, B.

    2008-01-01

    This study addresses the timing and causes of the Holocene population expansion of Fagus sylvatica at two sites in the southern Prealps (Italy): Lago di Fimon and Lago Piccolo di Avigliana. At both sites pollen and microcharcoal have been analysed at high temporal resolution. The impact of humans

  20. China's rapidly aging population creates policy challenges in shaping a viable long-term care system.

    Science.gov (United States)

    Feng, Zhanlian; Liu, Chang; Guan, Xinping; Mor, Vincent

    2012-12-01

    In China, formal long-term care services for the large aging population have increased to meet escalating demands as demographic shifts and socioeconomic changes have eroded traditional elder care. We analyze China's evolving long-term care landscape and trace major government policies and private-sector initiatives shaping it. Although home and community-based services remain spotty, institutional care is booming with little regulatory oversight. Chinese policy makers face mounting challenges overseeing the rapidly growing residential care sector, given the tension arising from policy inducements to further institutional growth, a weak regulatory framework, and the lack of enforcement capacity. We recommend addressing the following pressing policy issues: building a balanced system of services and avoiding an "institutional bias" that promotes rapid growth of elder care institutions over home or community-based care; strengthening regulatory oversight and quality assurance with information systems; and prioritizing education and training initiatives to grow a professionalized long-term care workforce.

  1. Emerging infectious disease leads to rapid population declines of common British birds.

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    Robert A Robinson

    Full Text Available Emerging infectious diseases are increasingly cited as threats to wildlife, livestock and humans alike. They can threaten geographically isolated or critically endangered wildlife populations; however, relatively few studies have clearly demonstrated the extent to which emerging diseases can impact populations of common wildlife species. Here, we report the impact of an emerging protozoal disease on British populations of greenfinch Carduelis chloris and chaffinch Fringilla coelebs, two of the most common birds in Britain. Morphological and molecular analyses showed this to be due to Trichomonas gallinae. Trichomonosis emerged as a novel fatal disease of finches in Britain in 2005 and rapidly became epidemic within greenfinch, and to a lesser extent chaffinch, populations in 2006. By 2007, breeding populations of greenfinches and chaffinches in the geographic region of highest disease incidence had decreased by 35% and 21% respectively, representing mortality in excess of half a million birds. In contrast, declines were less pronounced or absent in these species in regions where the disease was found in intermediate or low incidence. Also, populations of dunnock Prunella modularis, which similarly feeds in gardens, but in which T. gallinae was rarely recorded, did not decline. This is the first trichomonosis epidemic reported in the scientific literature to negatively impact populations of free-ranging non-columbiform species, and such levels of mortality and decline due to an emerging infectious disease are unprecedented in British wild bird populations. This disease emergence event demonstrates the potential for a protozoan parasite to jump avian host taxonomic groups with dramatic effect over a short time period.

  2. Emerging Infectious Disease Leads to Rapid Population Declines of Common British Birds

    Science.gov (United States)

    Toms, Mike P.; Peck, Kirsi M.; Kirkwood, James K.; Chantrey, Julian; Clatworthy, Innes R.; Evans, Andy D.; Hughes, Laura A.; Hutchinson, Oliver C.; John, Shinto K.; Pennycott, Tom W.; Perkins, Matthew W.; Rowley, Peter S.; Simpson, Vic R.; Tyler, Kevin M.; Cunningham, Andrew A.

    2010-01-01

    Emerging infectious diseases are increasingly cited as threats to wildlife, livestock and humans alike. They can threaten geographically isolated or critically endangered wildlife populations; however, relatively few studies have clearly demonstrated the extent to which emerging diseases can impact populations of common wildlife species. Here, we report the impact of an emerging protozoal disease on British populations of greenfinch Carduelis chloris and chaffinch Fringilla coelebs, two of the most common birds in Britain. Morphological and molecular analyses showed this to be due to Trichomonas gallinae. Trichomonosis emerged as a novel fatal disease of finches in Britain in 2005 and rapidly became epidemic within greenfinch, and to a lesser extent chaffinch, populations in 2006. By 2007, breeding populations of greenfinches and chaffinches in the geographic region of highest disease incidence had decreased by 35% and 21% respectively, representing mortality in excess of half a million birds. In contrast, declines were less pronounced or absent in these species in regions where the disease was found in intermediate or low incidence. Also, populations of dunnock Prunella modularis, which similarly feeds in gardens, but in which T. gallinae was rarely recorded, did not decline. This is the first trichomonosis epidemic reported in the scientific literature to negatively impact populations of free-ranging non-columbiform species, and such levels of mortality and decline due to an emerging infectious disease are unprecedented in British wild bird populations. This disease emergence event demonstrates the potential for a protozoan parasite to jump avian host taxonomic groups with dramatic effect over a short time period. PMID:20805869

  3. Orthopedic treatment of Class III malocclusion with rapid maxillary expansion combined with a face mask: a cephalometric assessment of craniofacial growth patterns

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    Daniella Torres Tagawa

    2012-06-01

    Full Text Available OBJECTIVE: The aim of this prospective study was to assess potential changes in the cephalometric craniofacial growth pattern of 17 children presenting Angle Class III malocclusion treated with a Haas-type expander combined with a face mask. METHODS: Lateral cephalometric radiographs were taken at beginning (T1 and immediately after removal of the appliances (T2, average of 11 months of treatment. Linear and angular measurements were used to evaluate the cranial base, dentoskeletal changes and facial growth pattern. RESULTS: The length of the anterior cranial base experienced a reduction while the posterior cranial base assumed a more vertical position at T1. Some maxillary movement occurred, there was no rotation of the palatal plane, there was a slight clockwise rotation of the mandible, although not significant. The ANB angle increased, thereby improving the relationship between the jaws; dentoalveolar compensation was more evident in the lower incisors. Five out of 12 cases (29.41% showed the following changes: In one case the pattern became more horizontal and in four cases more vertical. CONCLUSIONS: It was concluded after a short-term assessment that treatment with rapid maxillary expansion (RME associated with a face mask was effective in the correction of Class III malocclusion despite the changes in facial growth pattern observed in a few cases.

  4. Tongue posture improvement and pharyngeal airway enlargement as secondary effects of rapid maxillary expansion: a cone-beam computed tomography study.

    Science.gov (United States)

    Iwasaki, Tomonori; Saitoh, Issei; Takemoto, Yoshihiko; Inada, Emi; Kakuno, Eriko; Kanomi, Ryuzo; Hayasaki, Haruaki; Yamasaki, Youichi

    2013-02-01

    Rapid maxillary expansion (RME) is known to improve nasal airway ventilation. Recent evidence suggests that RME is an effective treatment for obstructive sleep apnea in children with maxillary constriction. However, the effect of RME on tongue posture and pharyngeal airway volume in children with nasal airway obstruction is not clear. In this study, we evaluated these effects using cone-beam computed tomography. Twenty-eight treatment subjects (mean age 9.96 ± 1.21 years) who required RME treatment had cone-beam computed tomography images taken before and after RME. Twenty control subjects (mean age 9.68 ± 1.02 years) received regular orthodontic treatment. Nasal airway ventilation was analyzed by using computational fluid dynamics, and intraoral airway (the low tongue space between tongue and palate) and pharyngeal airway volumes were measured. Intraoral airway volume decreased significantly in the RME group from 1212.9 ± 1370.9 mm(3) before RME to 279.7 ± 472.0 mm(3) after RME. Nasal airway ventilation was significantly correlated with intraoral airway volume. The increase of pharyngeal airway volume in the control group (1226.3 ± 1782.5 mm(3)) was only 41% that of the RME group (3015.4 ± 1297.6 mm(3)). In children with nasal obstruction, RME not only reduces nasal obstruction but also raises tongue posture and enlarges the pharyngeal airway. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  5. New Statistical Method to Analyze Three-Dimensional Landmark Configurations Obtained with Cone-Beam CT: Basic Features and Clinical Application for Rapid Maxillary Expansion

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    Gamble, Jennifer; Lagravere, Manuel O.; Major, Paul W.; Heo, Giseon [University of Alberta, Edmonton (Canada)

    2012-03-15

    To describe a statistical method of three-dimensional landmark configuration data and apply it to an orthodontic data set comparing two types of rapid maxillary expansion (RME) treatments. Landmark configurations obtained from cone beam CT scans were used to represent patients in two types (please describe what were two types) of RME groups and a control group over four time points. A method using tools from persistent homology and dimensionality reduction is presented and used to identify variability between the subjects. The analysis was in agreement with previous results using conventional methods, which found significant differences between treatment groups and the control, but no distinction between the types of treatment. Additionally, it was found that second molar eruption varied considerably between the subjects, and this has not been evaluated in previous analyses. This method of analysis allows entire configurations to be considered as a whole, and does not require specific inter-landmark distances or angles to be selected. Sources of variability present themselves, without having to be individually sought after. This method is suggested as an additional tool for the analysis of landmark configuration data.

  6. The Effects of Maxillary Protraction with or without Rapid Maxillary Expansion and Age Factors in Treating Class III Malocclusion: A Meta-Analysis

    Science.gov (United States)

    Zhang, Wei; Qu, Hong-Chen; Yu, Mo; Zhang, Yang

    2015-01-01

    We conducted a comprehensive meta-analysis of 12 studies to examine whether maxillary protraction face mask associated with rapid maxillary expansion (FM/RME) could be an effective treatment for Class III malocclusion and to evaluate the effect of timing on treatment response. Patients with a maxillary deficiency who were treated with FM with or without RME were compared with those who had an untreated Class III malocclusion. In both treatment groups, forward displacement of the maxilla and skeletal changes were found to be statistically significant. In addition, posterior rotation of the mandible and increased facial height were more evident in the FM group compared with the control group. However, no significant differences were observed between the early treatment groups and late treatment groups. The results indicated that both FM/RME and FM therapy produced favorable skeletal changes for correcting anterior crossbite, and the curative time was not affected by the presence of deciduous teeth, early mixed dentition or late mixed dentition in the patient. PMID:26068221

  7. The Effects of Maxillary Protraction with or without Rapid Maxillary Expansion and Age Factors in Treating Class III Malocclusion: A Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    Full Text Available We conducted a comprehensive meta-analysis of 12 studies to examine whether maxillary protraction face mask associated with rapid maxillary expansion (FM/RME could be an effective treatment for Class III malocclusion and to evaluate the effect of timing on treatment response. Patients with a maxillary deficiency who were treated with FM with or without RME were compared with those who had an untreated Class III malocclusion. In both treatment groups, forward displacement of the maxilla and skeletal changes were found to be statistically significant. In addition, posterior rotation of the mandible and increased facial height were more evident in the FM group compared with the control group. However, no significant differences were observed between the early treatment groups and late treatment groups. The results indicated that both FM/RME and FM therapy produced favorable skeletal changes for correcting anterior crossbite, and the curative time was not affected by the presence of deciduous teeth, early mixed dentition or late mixed dentition in the patient.

  8. Evaluation of opening pattern and bone neoformation at median palatal suture area in patients submitted to surgically assisted rapid maxillary expansion (SARME through cone beam computed tomography

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    Daniel Gomes SALGUEIRO

    2015-08-01

    Full Text Available AbstractSurgically assisted rapid maxillary expansion (SARME is the treatment of choice to adult patients even with severe transversal maxillary discrepancies. However, the adequate retention period to achieve the bone remodeling, thus assuring treatment stability, is controversial.Objective To evaluate the opening pattern and bone neoformation process at the midpalatal suture in patients submitted to surgically assisted (SARME through cone beam computed tomography (CBCT.Material and Methods Fourteen patients were submitted to SARME through subtotal Le Fort I osteotomy. Both the opening pattern and the mean bone density at midpalatal suture area to evaluate bone formation were assessed pre- and post-operatively (15, 60 and 180 days through CBCT.Results Type I opening pattern (from anterior to posterior nasal spine occurred in 12 subjects while type II opening pattern (from anterior nasal spine to transverse palatine suture occurred in 2 individuals. The 180-day postoperative mean (PO 180 of bone density value was 49.9% of the preoperative mean (Pre value.Conclusions The opening pattern of midpalatal suture is more related to patients’ age (23.9 years in type I and 33.5 years in type II and surgical technique. It was not possible to observe complete bone formation at midpalatal suture area at the ending of the retention period studied (180 days.

  9. Properties of chicken manure pyrolysis bio-oil blended with diesel and its combustion characteristics in RCEM, Rapid Compression and Expansion Machine

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    Sunbong Lee

    2014-06-01

    Full Text Available Bio-oil (bio-oil was produced from chicken manure in a pilot-scale pyrolysis facility. The raw bio-oil had a very high viscosity and sediments which made direct application to diesel engines difficult. The bio-oil was blended with diesel fuel with 25% and 75% volumetric ratio at the normal temperature, named as blend 25. A rapid compression and expansion machine was used for a combustion test under the experimental condition corresponding to the medium operation point of a light duty diesel engine using diesel fuel, and blend 25 for comparison. The injection related pressure signal and cylinder pressure signal were instantaneously picked up to analyze the combustion characteristics in addition to the measurement of NOx and smoke emissions. Blend 25 resulted in reduction of the smoke emission by 80% and improvements of the apparent combustion efficiency while the NOx emission increased by 40%. A discussion was done based on the analysis results of combustion.

  10. Rapid Decrease in Populations of Wild Ring-Tailed Lemurs (Lemur catta) in Madagascar.

    Science.gov (United States)

    LaFleur, Marni; Clarke, Tara A; Reuter, Kim; Schaeffer, Toby

    2016-01-01

    Lemurs are the most threatened group of mammals on earth. Lemur catta (ring-tailed lemur) represents one of the most iconic lemur species and faces numerous anthropogenic threats in the wild. In this study, we present population estimates from 32 sites across the range of L. catta, collected from primary and secondary data sources, to assess the number of ring-tailed lemurs left in the wild. We estimate that there are approximately 2,220 individual L. catta remaining in the 32 sites considered. We note local extinctions of populations of L. catta in at least 12 of the 32 sites examined, and that significantly more extinctions occurred in areas without some form of protection. This decrease in extant populations could represent a decrease of more than 95% of all ring-tailed lemurs in Madagascar since the year 2000. While these results should be considered preliminary, we stress the rapid decline of the species and note that habitat loss, bushmeat hunting and the illegal pet trade are driving populations to local extinction. Based on the data presented here, urgent and immediate funding and conservation action are crucial to ensure the viability of the remaining wild populations of ring-tailed lemurs. © 2017 S. Karger AG, Basel.

  11. Expansion of the National Salt Reduction Initiative: A Mathematical Model of Benefits and Risks of Population-Level Sodium Reduction.

    Science.gov (United States)

    Choi, Sung Eun; Brandeau, Margaret L; Basu, Sanjay

    2016-01-01

    The National Salt Reduction Initiative, in which food producers agree to lower sodium to levels deemed feasible for different foods, is expected to significantly reduce sodium intake if expanded to a large sector of food manufacturers. Given recent data on the relationship between sodium intake, hypertension, and associated cardiovascular disease at a population level, we sought to examine risks and benefits of the program. To estimate the impact of further expanding the initiative on hypertension, myocardial infarction (MI) and stroke incidence, and related mortality, given food consumption patterns across the United States, we developed and validated a stochastic microsimulation model of hypertension, MI, and stroke morbidity and mortality, using data from food producers on sodium reduction among foods, linked to 24-hour dietary recalls, blood pressure, and cardiovascular histories from the National Health and Nutrition Examination Survey. Expansion of the initiative to ensure all restaurants and manufacturers reach agreed-upon sodium targets would be expected to avert from 0.9 to 3.0 MIs (a 1.6%-5.4% reduction) and 0.5 to 2.8 strokes (a 1.1%-6.2% reduction) per 10,000 Americans per year over the next decade, after incorporating consumption patterns and variations in the effect of sodium reduction on blood pressure among different demographic groups. Even high levels of consumer addition of table salt or substitution among food categories would be unlikely to neutralize this benefit. However, if recent epidemiological associations between very low sodium and increased mortality are causal, then older women may be at risk of increased mortality from excessively low sodium intake. An expanded National Salt Reduction Initiative is likely to significantly reduce hypertension and hypertension-related cardiovascular morbidity but may be accompanied by potential risks to older women. © The Author(s) 2015.

  12. Validity and feasibility of a satellite imagery-based method for rapid estimation of displaced populations

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    Checchi Francesco

    2013-01-01

    Full Text Available Abstract Background Estimating the size of forcibly displaced populations is key to documenting their plight and allocating sufficient resources to their assistance, but is often not done, particularly during the acute phase of displacement, due to methodological challenges and inaccessibility. In this study, we explored the potential use of very high resolution satellite imagery to remotely estimate forcibly displaced populations. Methods Our method consisted of multiplying (i manual counts of assumed residential structures on a satellite image and (ii estimates of the mean number of people per structure (structure occupancy obtained from publicly available reports. We computed population estimates for 11 sites in Bangladesh, Chad, Democratic Republic of Congo, Ethiopia, Haiti, Kenya and Mozambique (six refugee camps, three internally displaced persons’ camps and two urban neighbourhoods with a mixture of residents and displaced ranging in population from 1,969 to 90,547, and compared these to “gold standard” reference population figures from census or other robust methods. Results Structure counts by independent analysts were reasonably consistent. Between one and 11 occupancy reports were available per site and most of these reported people per household rather than per structure. The imagery-based method had a precision relative to reference population figures of Conclusions In settings with clearly distinguishable individual structures, the remote, imagery-based method had reasonable accuracy for the purposes of rapid estimation, was simple and quick to implement, and would likely perform better in more current application. However, it may have insurmountable limitations in settings featuring connected buildings or shelters, a complex pattern of roofs and multi-level buildings. Based on these results, we discuss possible ways forward for the method’s development.

  13. Cancer survivors in Switzerland: a rapidly growing population to care for

    Science.gov (United States)

    2013-01-01

    Background Cancer survivors are a heterogeneous group with complex health problems. Data concerning its total number and growing dynamics for Switzerland are scarce and outdated. Methods Population and mortality data were retrieved from the Swiss Federal Statistical Office (FSO). Incidence and relative survival for invasive cancers were computed using data from the cancer registries Geneva (1970–2009), St. Gallen - Appenzell (1980–2010), Grisons & Glarus (1989–2010), and Valais (1989–2010). We estimated prevalence for 1990–2010 using the Prevalence, Incidence Approach MODel (PIAMOD) method. We calculated trends in prevalence estimates by Joinpoint analysis. Projections were extrapolated using the above models and based on time trends of the period 2007–2010. Results The estimated number of cancer survivors increased from 139′717 in 1990 (2.08% of the population) to 289′797 persons in 2010 (3.70%). The growth rate shows an exponential shape and was 3.3% per year in the period 2008 to 2010. Almost half of the survivors have a history of breast, prostate or colorectal cancer. Among cancer survivors, 55% are women but the increases have been more marked in men (p Switzerland. Conclusions There is a rapidly growing population of cancer survivors in Switzerland whose needs and concerns are largely unknown. PMID:23764068

  14. Rapid Population Growth and Human Carrying Capacity: Two Perspectives. World Bank Staff Working Papers No. 690 and Population and Development Series No. 15.

    Science.gov (United States)

    Mahar, Dennis J., Ed.; And Others

    Two perspectives on carrying capacity and population growth are examined. The first perspective, "Carrying Capacity and Rapid Population Growth: Definition, Cases, and Consequences" (Robert Muscat), explores the possible meanings of the idea of carrying capacity under developing country conditions, looks at historical and present-day cases of…

  15. Evidence from phylogenetic and genome fingerprinting analyses suggests rapidly changing variation in Halorubrum and Haloarcula populations

    Science.gov (United States)

    Ram Mohan, Nikhil; Fullmer, Matthew S.; Makkay, Andrea M.; Wheeler, Ryan; Ventosa, Antonio; Naor, Adit; Gogarten, J. Peter; Papke, R. Thane

    2014-01-01

    Halobacteria require high NaCl concentrations for growth and are the dominant inhabitants of hypersaline environments above 15% NaCl. They are well-documented to be highly recombinogenic, both in frequency and in the range of exchange partners. In this study, we examine the genetic and genomic variation of cultured, naturally co-occurring environmental populations of Halobacteria. Sequence data from multiple loci (~2500 bp) identified many closely and more distantly related strains belonging to the genera Halorubrum and Haloarcula. Genome fingerprinting using a random priming PCR amplification method to analyze these isolates revealed diverse banding patterns across each of the genera and surprisingly even for isolates that are identical at the nucleotide level for five protein coding sequenced loci. This variance in genome structure even between identical multilocus sequence analysis (MLSA) haplotypes indicates that accumulation of genomic variation is rapid: faster than the rate of third codon substitutions. PMID:24782838

  16. Evidence from phylogenetic and genome fingerprinting analyses suggests rapidly changing variation in Halorubrum and Haloarcula populations

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    Nikhil eRam Mohan

    2014-04-01

    Full Text Available Halobacteria require high NaCl concentrations for growth and are the dominant inhabitants of hypersaline environments above 15% NaCl. They are well documented to be highly recombinogenic, both in frequency and in the range of exchange partners. In this study, we examine the genetic and genomic variation of cultured, naturally co-occurring environmental populations of Halobacteria. Sequence data from multiple loci (~2500bp identified closely related strains belonging to the genera Halorubrum and Haloarcula. Genome fingerprinting using a random priming PCR amplification method to analyze these isolates revealed diverse banding patterns within and across each of the genera and surprisingly even for isolates that are identical at the nucleotide level for five protein coding sequenced loci. This variance in genome structure even between identical multilocus sequence analysis (MLSA haplotypes suggests that accumulation of variation is rapid, perhaps occurring every generation.

  17. Disease-associated CAG·CTG triplet repeats expand rapidly in non-dividing mouse cells, but cell cycle arrest is insufficient to drive expansion.

    Science.gov (United States)

    Gomes-Pereira, Mário; Hilley, James D; Morales, Fernando; Adam, Berit; James, Helen E; Monckton, Darren G

    2014-06-01

    Genetically unstable expanded CAG·CTG trinucleotide repeats are causal in a number of human disorders, including Huntington disease and myotonic dystrophy type 1. It is still widely assumed that DNA polymerase slippage during replication plays an important role in the accumulation of expansions. Nevertheless, somatic mosaicism correlates poorly with the proliferative capacity of the tissue and rates of cell turnover, suggesting that expansions can occur in the absence of replication. We monitored CAG·CTG repeat instability in transgenic mouse cells arrested by chemical or genetic manipulation of the cell cycle and generated unequivocal evidence for the continuous accumulation of repeat expansions in non-dividing cells. Importantly, the rates of expansion in non-dividing cells were at least as high as those of proliferating cells. These data are consistent with a major role for cell division-independent expansion in generating somatic mosaicism in vivo. Although expansions can accrue in non-dividing cells, we also show that cell cycle arrest is not sufficient to drive instability, implicating other factors as the key regulators of tissue-specific instability. Our data reveal that de novo expansion events are not limited to S-phase and further support a cell division-independent mutational pathway. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  18. Neptune: a bioinformatics tool for rapid discovery of genomic variation in bacterial populations.

    Science.gov (United States)

    Marinier, Eric; Zaheer, Rahat; Berry, Chrystal; Weedmark, Kelly A; Domaratzki, Michael; Mabon, Philip; Knox, Natalie C; Reimer, Aleisha R; Graham, Morag R; Chui, Linda; Patterson-Fortin, Laura; Zhang, Jian; Pagotto, Franco; Farber, Jeff; Mahony, Jim; Seyer, Karine; Bekal, Sadjia; Tremblay, Cécile; Isaac-Renton, Judy; Prystajecky, Natalie; Chen, Jessica; Slade, Peter; Van Domselaar, Gary

    2017-10-13

    The ready availability of vast amounts of genomic sequence data has created the need to rethink comparative genomics algorithms using 'big data' approaches. Neptune is an efficient system for rapidly locating differentially abundant genomic content in bacterial populations using an exact k-mer matching strategy, while accommodating k-mer mismatches. Neptune's loci discovery process identifies sequences that are sufficiently common to a group of target sequences and sufficiently absent from non-targets using probabilistic models. Neptune uses parallel computing to efficiently identify and extract these loci from draft genome assemblies without requiring multiple sequence alignments or other computationally expensive comparative sequence analyses. Tests on simulated and real datasets showed that Neptune rapidly identifies regions that are both sensitive and specific. We demonstrate that this system can identify trait-specific loci from different bacterial lineages. Neptune is broadly applicable for comparative bacterial analyses, yet will particularly benefit pathogenomic applications, owing to efficient and sensitive discovery of differentially abundant genomic loci. The software is available for download at: http://github.com/phac-nml/neptune. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  19. Rapid assessment of visual impairment in urban population of Delhi, India.

    Science.gov (United States)

    Gupta, Noopur; Vashist, Praveen; Malhotra, Sumit; Senjam, Suraj Singh; Misra, Vasundhara; Bhardwaj, Amit

    2015-01-01

    To determine the prevalence, causes and associated demographic factors related to visual impairment amongst the urban population of New Delhi, India. A population-based, cross-sectional study was conducted in East Delhi district using cluster random sampling methodology. This Rapid Assessment of Visual Impairment (RAVI) survey involved examination of all individuals aged 40 years and above in 24 randomly selected clusters of the district. Visual acuity (VA) assessment and comprehensive ocular examination were done during the door-to-door survey. A questionnaire was used to collect personal and demographic information of the study population. Blindness and Visual Impairment was defined as presenting VA visual impairment. Of 2421 subjects enumerated, 2331 (96.3%) were available for ophthalmic examination. Among those examined, 49.3% were males. The prevalence of visual impairment (VI) in the study population, was 11.4% (95% C.I. 10.1, 12.7) and that of blindness was 1.2% (95% C.I. 0.8, 1.6). Uncorrected refractive error was the leading cause of VI accounting for 53.4% of all VI followed by cataract (33.8%). With multivariable logistic regression, the odds of having VI increased with age (OR = 24.6[95% C.I.: 14.9, 40.7]; p visual impairment is considerable in this region despite availability of adequate eye care facilities. Awareness generation and simple interventions like cataract surgery and provision of spectacles will help to eliminate the major causes of blindness and visual impairment in this region.

  20. Application of Molecular Cytogenetic Technique for Rapid Prenatal Diagnosis of Aneuploidies in Iranian Population

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    Habib Nasiri

    2009-06-01

    Full Text Available Objective: Classic cell culture and karyotyping is routinely used for prenatal detection of different chromosomal abnormalities. Molecular cytogenetic techniques have also recently been developed and used for this purpose. Quantitative florescence PCR using short tandem repeat (STR markers has more potential for high throughput diagnosis. Marker heterozygosity in short tandem repeats (STR is of critical importance in the clinical applicablity of this method. Materials and Methods: Different STR markers on chromosomes 13, 18, 21, X and Y  were analysed from  amniotic samples to detect related disorders such as Down, Edward, Patau,  Klinefelter sundromes , as well as sex chromosomes numerical abnormalities . Results: In our population some markers (D18S976, DXS6854, D21S11, and D21S1411 showed alleles with sizes out of expected ranges. But others occupied narrower range of predicted distribution. Most markers have enough heterozygosity (66.3-94.7 to be used for prenatal diagnosis. Furthermore, results obtained from full karyotype for all samples were in concordance with results of molecular cytogenetic testing. Conclusion: It is concluded that, in urgent situations, if proper markers used, molecular cytogenetic testing (QF-PCR could be a useful method for rapid prenatal diagnosis (PND in populations with high rate of consanguinity such as Iran.  

  1. Episodic Neoglacial expansion and rapid 20th century retreat of a small ice cap on Baffin Island, Arctic Canada, and modeled temperature change

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    S. L. Pendleton

    2017-11-01

    Full Text Available Records of Neoglacial glacier activity in the Arctic constructed from moraines are often incomplete due to a preservation bias toward the most extensive advance, often the Little Ice Age. Recent warming in the Arctic has caused extensive retreat of glaciers over the past several decades, exposing preserved landscapes complete with in situ tundra plants previously entombed by ice. The radiocarbon ages of these plants define the timing of snowline depression and glacier advance across the site, in response to local summer cooling. Erosion rapidly removes most dead plants that have been recently exposed by ice retreat, but where erosive processes are unusually weak, dead plants may remain preserved on the landscape for decades. In such settings, a transect of plant radiocarbon ages can be used to construct a near-continuous chronology of past ice margin advance. Here we present radiocarbon dates from the first such transect on Baffin Island, which directly dates the advance of a small ice cap over the past two millennia. The nature of ice expansion between 20 BCE and ∼ 1000 CE is still uncertain, but episodic advances at ∼ 1000 CE, ∼ 1200, and  ∼ 1500 led to the maximum Neoglacial dimensions ~ 1900 CE. We employ a two-dimensional numerical glacier model calibrated using the plant radiocarbon ages ice margin chronology to assess the sensitivity of the ice cap to temperature change. Model experiments show that at least ∼ 0.44 °C of cooling over the past 2 kyr is required for the ice cap to reach its 1900 CE margin, and that the period from ∼ 1000 to 1900 CE must have been at least 0.25° C cooler than the previous millennium, results that agree with regional temperature reconstructions and climate model simulations. However, significant warming since 1900 CE is required to explain retreat to its present position, and, at the same rate of warming, the ice cap will disappear before 2100 CE.

  2. Population dynamics of Empetrum hermaphroditum (Ericaceae) on a subarctic sand dune: Evidence of rapid colonization through efficient sexual reproduction.

    Science.gov (United States)

    Boudreau, Stéphane; Ropars, Pascale; Harper, Karen Amanda

    2010-05-01

    The importance of sexual reproduction for clonal plant species has long been underestimated, perhaps as a consequence of the difficulty in identifying individuals, preventing the study of their population dynamics. Such is the case for Empetrum hermaphroditum, an ericaceous species, which dominates the ground vegetation of subarctic ecosystems. Despite abundant seed production, seedlings are rarely observed. Therefore, prevalent seedling recruitment on a subarctic dune system provided an opportunity to study the population dynamics and spatial pattern of the colonization phase of this species. We established a 6-ha grid on the dune systems that extended from the shoreline to the fixed dunes and mapped and measured all E. hermaphroditum individuals in the grid. Moreover, we sampled 112 individuals just outside the grid to identify any allometric relationship between the size and age of the individuals, which allowed us to reconstruct population expansion. The overall size structure suggests that the population is still expanding. In the last 50 yr, E. hermaphroditum advanced more than 200 m in the dune system. Expansion started in the 1960s simultaneously at different distances from the shoreline. Colonization did not proceed gradually from the fixed dune toward the shoreline but instead individuals established earlier in the troughs between the dunes, with an increasingly clumped spatial pattern as the population filled in with time.

  3. North and South Indian populations share a common ancestral origin of Friedreich's ataxia but vary in age of GAA repeat expansion.

    Science.gov (United States)

    Singh, Inder; Faruq, Mohammed; Mukherjee, Odity; Jain, Sanjeev; Pal, Pramod Kumar; Srivastav, M V Padma; Behari, Madhuri; Srivastava, Achal K; Mukerji, Mitali

    2010-05-01

    Friedreich's ataxia (FRDA) is caused by expansion of GAA repeats in the frataxin (FXN) gene on chromosome 9q13-q21.1. We analysed the origin of FRDA in 21 North Indian (NI) and eight South Indian (SI) families using five single nucleotide polymorphisms (SNPs) and a microsatellite marker spanning the GAA repeats. The NI and SI families were derived from Indo-European and Dravidian linguistic backgrounds respectively. The frequency of large normal (LNs) alleles of the GAA repeat correlate with the overall lower prevalence of FRDA in India compared to the European population. All of the expanded alleles in the Indian population share a common core haplotype suggesting a founder effect. The expanded alleles in the NI population demonstrate more similarity to those of Europeans in terms of age of GAA repeat expansion (15975 +/- 2850 years) and association of LNs with expanded alleles. FRDA seems to have been introduced recently in the South Indian population since the average estimated age of the mutation in SI is 5425 +/- 1750 years and unlike NI some of the haplotypes of LNs are not associated with the expanded alleles.

  4. Rapid assessment of trachoma in underserved population of Car-Nicobar Island, India.

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    Praveen Vashist

    Full Text Available PURPOSE: To determine the burden of trachoma and its related risk factors amongst the native population of Car-Nicobar Island in India. METHODS: Rapid assessment for trachoma was conducted in ten villages of Car-Nicobar Island according to standard WHO guidelines. An average of 50 children aged 1-9 years were assessed clinically for signs of active trachoma and facial cleanliness in each village. Additionally, all adults above 15 years of age in these households were examined for evidence of trachomatous trichiasis and corneal opacity. Environmental risk factors contributing to trachoma like limited access to potable water & functional latrine, presence of animal pen and garbage within the Nicobari hut were also noted in all villages. RESULTS: Out of a total of fifteen villages in Car-Nicobar Island, ten villages were selected for trachoma survey depending on evidence of socio-developmental indicators like poverty and decreased access to water, sanitation and healthcare facilities. The total population of the selected clusters was 7277 in the ten villages. Overall, 251 of 516 children (48.6%;CI: 46.5-55.1 had evidence of follicular stage of trachoma and 11 children (2.1%;CI:1.0-3.4 had evidence of inflammatory stage of trachoma. Nearly 15%(CI:12.1-18.3 children were noted to have unclean faces in the ten villages. Trachomatous trichiasis was noted in 73 adults (1.0%;CI:0.8-1.2. The environmental sanitation was not found to be satisfactory in the surveyed villages mainly due to the co-habitance of Nicobari people with domestic animals like pigs, hens, goats, dogs, cats etc in most (96.4% of the households. CONCLUSION: Active trachoma and trachomatous trichiasis was observed in all the ten villages surveyed, wherein trachoma control measures are needed.

  5. Cast Off expansion plan by rapid improvement through Optimization tool design, Tool Parameters and using Six Sigma’s ECRS Technique

    Science.gov (United States)

    Gopalakrishnan, T.; Saravanan, R.

    2017-03-01

    Powerful management concepts step-up the quality of the product, time saving in producing the product thereby increase the production rate, improves tools and techniques, work culture, work place and employee motivation and morale. In this paper discussed about the case study of optimizing the tool design, tool parameters to cast off expansion plan according ECRS technique. The proposed designs and optimal tool parameters yielded best results and meet the customer demand without expansion plan. Hence the work yielded huge savings of money (direct and indirect cost), time and improved the motivation and more of employees significantly.

  6. Rapid assessment of populations trends of invasive species: Singular Spectrum Analysis (SSA

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    DANA, ED

    2010-01-01

    Full Text Available Singular Spectrum Analysis (SSA is a powerful analytical approach for biodi-versity management. Its main advan-tages are due to its intuitive processing and visualization, since mathematical workflow is conceptually similar to the widely accepted Principal Components Analysis. Detailed analyses of popula-tion trends with mathematical tools are often difficult to achieve for managers by a number of reasons (large numbers or areas monitored, large number of species, insufficient statistics skills, strong knowledge level in demographic analyses, etc.. SSA has been used since the 1970’s in signal processing to clarify signal vs. noisy information, but it has also been used in climate change analy-sis and other developmental areas. Be-sides, SSA is a rapid-learning method for technicians and managers with medium level of mathematical knowledge. Free software in Unix environment is avail-able. Unfortunately, no free and friendly software is available for Win-dows SO. Although R package may offer solutions for really advanced users, it does not fit real work situations for managers of biological invasions. Cater-pillar (Gistat Group, Ltd is by now, the best option found by the author in terms of price, facility for results inter-pretation and time consumed in learn-ing. The main disadvantage is the poor content of tutorial files

  7. Investigation of QF-PCR Application for Rapid Prenatal Diagnosis of Chromosomal Aneuploidies in Iranian Population.

    Science.gov (United States)

    Nasiri, Habib; Noori-Dalooi, Mohammad-Reza; Dastan, Jila; Ghaffari, Saeed-Reza

    2011-03-01

    G-Banding followed by standard chromosome analysis is routinely used for prenatal detection of chromosomal abnormalities. In recent years, molecular cytogenetic techniques have been developed for rapid diagnosis of chromosomal abnormalities. Among these methods Quantitative Florescence Polymerase Chain Reaction (QF-PCR) has been widely used for this purpose. Heterozygosity of short tandem repeat (STR) markers which leads to informativity is the most critical requirement for feasibility of QF-PCR. In this study we analyzed several short tandem repeats on chromosomes 13, 18, 21, X and Y on amniotic fluid samples obtained from PND candidates to diagnose conditions such as Down, Edward and Patau syndromes and also numerical sex chromosome abnormalities such as Klinefelter and Turner syndromes. Most of the analyzed STRs had acceptable heterozygosity (66.3-94.7) to be used in QF-PCR based prenatal diagnosis. Moreover, results obtained from both methods (standard karyotype and QF-PCR) for all samples were in accordance with each other. In case of using appropriate STR markers, and in certain clinical indications, QF-PCR could be used as useful technique for prenatal diagnosis even in consanguine populations such as Iranians.

  8. Human CD4+ CD25hi Foxp3+ regulatory T cells are derived by rapid turnover of memory populations in vivo

    Science.gov (United States)

    Vukmanovic-Stejic, Milica; Zhang, Yan; Cook, Joanne E.; Fletcher, Jean M.; McQuaid, Arthur; Masters, Joanne E.; Rustin, Malcolm H.A.; Taams, Leonie S.; Beverley, Peter C.L.; Macallan, Derek C.; Akbar, Arne N.

    2006-01-01

    While memory T cells are maintained by continuous turnover, it is not clear how human regulatory CD4+CD45RO+CD25hi Foxp3+ T lymphocyte populations persist throughout life. We therefore used deuterium labeling of cycling cells in vivo to determine whether these cells could be replenished by proliferation. We found that CD4+CD45RO+Foxp3+CD25hi T lymphocytes were highly proliferative, with a doubling time of 8 days, compared with memory CD4+CD45RO+Foxp3–CD25– (24 days) or naive CD4+CD45RA+Foxp3–CD25– populations (199 days). However, the regulatory population was susceptible to apoptosis and had critically short telomeres and low telomerase activity. It was therefore unlikely to be self regenerating. These data are consistent with continuous production from another population source. We found extremely close TCR clonal homology between regulatory and memory CD4+ T cells. Furthermore, antigen-related expansions within certain TCR Vβ families were associated with parallel numerical increases of CD4+CD45RO+CD25hiFoxp3+ Tregs with the same Vβ usage. It is therefore unlikely that all human CD4+CD25+Foxp3+ Tregs are generated as a separate functional lineage in the thymus. Instead, our data suggest that a proportion of this regulatory population is generated from rapidly dividing, highly differentiated memory CD4+ T cells; this has considerable implications for the therapeutic manipulation of these cells in vivo. PMID:16955142

  9. When evolution is the solution to pollution: Key principles, and lessons from rapid repeated adaptation of killifish (Fundulus heteroclitus) populations

    OpenAIRE

    Whitehead, Andrew; Clark, Bryan W.; Reid, Noah M.; Hahn, Mark E.; Nacci, Diane

    2017-01-01

    Abstract For most species, evolutionary adaptation is not expected to be sufficiently rapid to buffer the effects of human‐mediated environmental changes, including environmental pollution. Here we review how key features of populations, the characteristics of environmental pollution, and the genetic architecture underlying adaptive traits, may interact to shape the likelihood of evolutionary rescue from pollution. Large populations of Atlantic killifish (Fundulus heteroclitus) persist in som...

  10. When evolution is the solution to pollution: Key principles, and lessons from rapid repeated adaptation of killifish (Fundulus heteroclitus) populations

    Science.gov (United States)

    For most species, evolutionary adaptation is not expected to be sufficiently rapid to buffer the effects of human-mediated environmental changes. Yet large persistent populations of small bodied fish residing in some of the most contaminated estuaries of the US have provided some...

  11. Gametogenesis of an intertidal population of Mytilus trossulus in NW Greenland: not a limitation for potential Arctic range expansion

    DEFF Research Database (Denmark)

    Thyrring, Jakob; Jensen, Kurt Thomas; Sejr, Mikael Kristian

    2017-01-01

    The drivers determining species’ northern distribution limits remain elusive and, combined with inadequate knowledge of past and current distribution ranges, this prevents accurate determination of potential changes in the Arctic. The northernmost population of the bivalve Mytilus trossulus is fo...

  12. Postglacial north-south expansion of populations of Rhizophora mangle (Rhizophoraceae) along the Brazilian coast revealed by microsatellite analysis.

    Science.gov (United States)

    Pil, Maria W; Boeger, Maria R T; Muschner, Valéria C; Pie, Marcio R; Ostrensky, Antonio; Boeger, Walter A

    2011-06-01

    Red mangrove (Rhizophora mangle) dominates tropical tidal areas along both sides of the Atlantic, yet little is known about its degree of population differentiation over large geographical scales. Information on the genetic variability of mangrove species along the Brazilian coast is important not only for understanding the recent gene flow dynamic between populations, but also to evaluate models of evolutionary diversification and develop effective strategies for conservation. We investigated the genetic variability of the red mangrove along the Brazilian coast. Eight microsatellite loci were used to genotype 145 individuals across 10 populations spanning more than 4500 km of coast line. We estimated the genetic variability and structure of the populations and the historical gene flow between them. The level of genetic variability was low, with only 27 different alleles being detected and allele richness between 1.25 and 2.75. On the other hand, there was substantial population differentiation (R(st) = 0.48; P mangroves, which likely remained stable during the Quaternary glaciations. The lowest variability observed in the southern populations of the red mangrove most likely reflects their recent age, associated with allelic reduction, resulting from the consecutive founder events that followed subsequent colonization of estuaries during the gradual warming by the end of the last glacial period.

  13. Accelerated production of antigen-specific T cells for preclinical and clinical applications using gas-permeable rapid expansion cultureware (G-Rex).

    Science.gov (United States)

    Vera, Juan F; Brenner, Lara J; Gerdemann, Ulrike; Ngo, Minhtran C; Sili, Uluhan; Liu, Hao; Wilson, John; Dotti, Gianpietro; Heslop, Helen E; Leen, Ann M; Rooney, Cliona M

    2010-04-01

    The clinical manufacture of antigen-specific cytotoxic T lymphocytes (CTLs) for adoptive immunotherapy is limited by the complexity and time required to produce large numbers with the desired function and specificity. The culture conditions required are rigorous, and in some cases only achieved in 2-cm wells in which cell growth is limited by gas exchange, nutrients, and waste accumulation. Bioreactors developed to overcome these issues tend to be complex, expensive, and not always conducive to CTL growth. We observed that antigen-specific CTLs undergo 7 to 10 divisions poststimulation. However, the expected CTL numbers were achieved only in the first week of culture. By recreating the culture conditions present during this first week-low frequency of antigen-specific T cells and high frequency of feeder cells-we were able to increase CTL expansion to expected levels that could be sustained for several weeks without affecting phenotype or function. However, the number of 24-well plates needed was excessive and cultures required frequent media changes, increasing complexity and manufacturing costs. Therefore, we evaluated novel gas-permeable culture devices (G-Rex) with a silicone membrane at the base allowing gas exchange to occur uninhibited by the depth of the medium above. This system effectively supports the expansion of CTL and actually increases output by up to 20-fold while decreasing the required technician time. Importantly, this amplified cell expansion is not because of more cell divisions but because of reduced cell death. This bioprocess optimization increased T-cell output while decreasing the complexity and cost of CTL manufacture, making cell therapy more accessible.

  14. Homogeneous population of the brown alga Sargassum polycystum in Southeast Asia: possible role of recent expansion and asexual propagation.

    Directory of Open Access Journals (Sweden)

    Sze Wai Chan

    Full Text Available Southeast Asia has been known as one of the biodiversity hotspots in the world. Repeated glacial cycles during Pleistocene were believed to cause isolation of marine taxa in refugia, resulting in diversification among lineages. Recently, ocean current was also found to be another factor affecting gene flow by restricting larval dispersal in animals. Macroalgae are unique in having mode of reproduction that differs from that of animals. Our study on the phylogeographical pattern of the brown macroalga Sargassum polycystum using nuclear Internal Transcribed Spacer 2 (ITS2, plastidal RuBisCO spacer (Rub spacer and mitochondrial cytochrome oxidase subunit-III (Cox3 as molecular markers revealed genetic homogeneity across 27 sites in Southeast Asia and western Pacific, in sharp contrast to that revealed from most animal studies. Our data suggested that S. polycystum persisted in single refugium during Pleistocene in a panmixia pattern. Expansion occurred more recently after the Last Glacial Maximum and recolonization of the newly flooded Sunda Shelf could have involved asexual propagation of the species. High dispersal ability through floating fronds carrying developing germlings may also contribute to the low genetic diversity of the species.

  15. Ancient female philopatry, asymmetric male gene flow, and synchronous population expansion support the influence of climatic oscillations on the evolution of South American sea lion (Otaria flavescens.

    Directory of Open Access Journals (Sweden)

    Larissa Rosa de Oliveira

    Full Text Available The South American sea lion (Otaria flavescens is widely distributed along the southern Atlantic and Pacific coasts of South America with a history of significant commercial exploitation. We aimed to evaluate the population genetic structure and the evolutionary history of South American sea lion along its distribution by analyses of mitochondrial DNA (mtDNA and 10 nuclear microsatellites loci. We analyzed 147 sequences of mtDNA control region and genotyped 111 individuals of South American sea lion for 10 microsatellite loci, representing six populations (Peru, Northern Chile, Southern Chile, Uruguay (Brazil, Argentina and Falkland (Malvinas Islands and covering the entire distribution of the species. The mtDNA phylogeny shows that haplotypes from the two oceans comprise two very divergent clades as observed in previous studies, suggesting a long period (>1 million years of low inter-oceanic female gene flow. Bayesian analysis of bi-parental genetic diversity supports significant (but less pronounced than mitochondrial genetic structure between Pacific and Atlantic populations, although also suggested some inter-oceanic gene flow mediated by males. Higher male migration rates were found in the intra-oceanic population comparisons, supporting very high female philopatry in the species. Demographic analyses showed that populations from both oceans went through a large population expansion ~10,000 years ago, suggesting a very similar influence of historical environmental factors, such as the last glacial cycle, on both regions. Our results support the proposition that the Pacific and Atlantic populations of the South American sea lion should be considered distinct evolutionarily significant units, with at least two managements units in each ocean.

  16. Ancient female philopatry, asymmetric male gene flow, and synchronous population expansion support the influence of climatic oscillations on the evolution of South American sea lion (Otaria flavescens)

    Science.gov (United States)

    Gehara, Marcelo C. M.; Fraga, Lúcia D.; Lopes, Fernando; Túnez, Juan Ignacio; Cassini, Marcelo H.; Majluf, Patricia; Cárdenas-Alayza, Susana; Pavés, Héctor J.; Crespo, Enrique Alberto; García, Nestor; Loizaga de Castro, Rocío; Hoelzel, A. Rus; Sepúlveda, Maritza; Olavarría, Carlos; Valiati, Victor Hugo; Quiñones, Renato; Pérez-Alvarez, Maria Jose; Ott, Paulo Henrique

    2017-01-01

    The South American sea lion (Otaria flavescens) is widely distributed along the southern Atlantic and Pacific coasts of South America with a history of significant commercial exploitation. We aimed to evaluate the population genetic structure and the evolutionary history of South American sea lion along its distribution by analyses of mitochondrial DNA (mtDNA) and 10 nuclear microsatellites loci. We analyzed 147 sequences of mtDNA control region and genotyped 111 individuals of South American sea lion for 10 microsatellite loci, representing six populations (Peru, Northern Chile, Southern Chile, Uruguay (Brazil), Argentina and Falkland (Malvinas) Islands) and covering the entire distribution of the species. The mtDNA phylogeny shows that haplotypes from the two oceans comprise two very divergent clades as observed in previous studies, suggesting a long period (>1 million years) of low inter-oceanic female gene flow. Bayesian analysis of bi-parental genetic diversity supports significant (but less pronounced than mitochondrial) genetic structure between Pacific and Atlantic populations, although also suggested some inter-oceanic gene flow mediated by males. Higher male migration rates were found in the intra-oceanic population comparisons, supporting very high female philopatry in the species. Demographic analyses showed that populations from both oceans went through a large population expansion ~10,000 years ago, suggesting a very similar influence of historical environmental factors, such as the last glacial cycle, on both regions. Our results support the proposition that the Pacific and Atlantic populations of the South American sea lion should be considered distinct evolutionarily significant units, with at least two managements units in each ocean. PMID:28654647

  17. Nuclear expansion with excitation

    Energy Technology Data Exchange (ETDEWEB)

    De, J.N. [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India); Departament d' Estructura i Constituents de la Materia, Facultat de Fisica, Universitat de Barcelona, Diagonal 647, 08028 Barcelona (Spain); Samaddar, S.K. [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India); Vinas, X. [Departament d' Estructura i Constituents de la Materia, Facultat de Fisica, Universitat de Barcelona, Diagonal 647, 08028 Barcelona (Spain); Centelles, M. [Departament d' Estructura i Constituents de la Materia, Facultat de Fisica, Universitat de Barcelona, Diagonal 647, 08028 Barcelona (Spain)]. E-mail: mario@ecm.ub.es

    2006-07-06

    The expansion of an isolated hot spherical nucleus with excitation energy and its caloric curve are studied in a thermodynamic model with the SkM{sup *} force as the nuclear effective two-body interaction. The calted results are shown to compare well with the recent experimental data from energetic nuclear collisions. The fluctuations in temperature and density are also studied. They are seen to build up very rapidly beyond an excitation energy of {approx}9 MeV/u. Volume-conserving quadrupole deformation in addition to expansion indicates, however, nuclear disassembly above an excitation energy of {approx}4 MeV/u.

  18. Cryptic speciation in the recently discovered American cycliophoran Symbion americanus; genetic structure and population expansion

    DEFF Research Database (Denmark)

    Baker, J.M.; Funch, Peter; Giribet, G.

    2007-01-01

      Symbion americanus was recently described as the second species in the phylum Cycliophora, living commensally on the American commercial lobster Homarus americanus. A previous genetic analysis of American and European populations of cycliophorans suggested that haplotype divergence in S....... americanus was much greater than in its European counterpart S. pandora. This study examined the population structure and demographics of 169 individuals thought to belong to S. americanus collected from lobsters over 13 North American localities (Nova Scotia, Canada to Maryland, USA) between October 2003...... and January 2006. Cytochrome c oxidase subunit I sequence data clearly suggested the presence of three cryptic lineages in a species complex, often co-occurring in the same lobster specimens. One of these lineages, named the "G" lineage, was represented by very few individuals and therefore was excluded from...

  19. Prospects for population expansion of the exotic aoudad (Ammotragus lervia; Bovidae) in the Iberian Peninsula: clues from habitat suitability modelling

    DEFF Research Database (Denmark)

    Cassinello, Jorge; Acevedo, Pelayo; Hortal, Joaquín

    2006-01-01

    ) environmental variables (climate and habitat type), and (2) potential aoudad landscape avoidance and human disturbance variables. We compared both niche descriptions to study the impact of human interference on niche selection of the species. ENFA models were calibrated using data on the population expanded...... from the original release location, in Sierra Espuña mountains, and validated using data from another free-ranging population, originated independently in the Alicante province. The habitat suitability model for the purely environmental niche predicts a potential distribution along a SW-NE axis...... for the species. Since the aoudad is a potential competitor of native ungulates and a threat to endemic flora, prospects for its potential dispersion might be of great conservation value....

  20. Rapid Adaptation of a Daphnia magna Population to Metal Stress Is Associated with Heterozygote Excess.

    Science.gov (United States)

    Hochmuth, Jennifer D; De Meester, Luc; Pereira, Cecília M S; Janssen, Colin R; De Schamphelaere, Karel A C

    2015-08-04

    Although natural populations can harbor evolutionary potential to adapt genetically to chemical stress, it is often thought that natural selection leads to a general reduction of genetic diversity and involves costs. Here, a 10 week microevolution experiment was conducted with a genetically diverse and representative sample of one natural Daphnia magna population that was exposed to copper and zinc. Both Cu- and Zn-selected populations developed a significantly higher metal tolerance (i.e., genetic adaptation), indicated by higher reproduction probabilities of clonal lines in Cu and Zn exposures than observed for the original and control populations. The complete recovery of the population densities after 10 weeks of Zn selection (following an initial decrease of 74%) illustrates an example of evolutionary rescue. Microsatellite genotyping revealed a decrease in clonal diversity but no change in allelic richness, and showed an excess in heterozygosity in the Cu- and Zn-selected populations compared to the control and original populations. The excess heterozygosity in metal-selected populations that we observed has important consequences for risk assessment, as it contributes to the maintenance of a higher allelic diversity under multigenerational chemical exposure. This study is, to our knowledge, the first report of an increase in heterozygosity following multigenerational exposure to metal stress, despite a decline in clonal diversity. In a follow-up study with the Zn-selected populations, we observed no effect of Zn selection on the tolerance to heat and cyanobacteria. However, we observed higher tolerance to Cd in the Zn-selected than in the original and control populations if the 20% effective concentration of Cd was considered (cross-tolerance). Our results suggest only limited costs of adaptation but future research is needed to evaluate the adaptive potential of metal-selected populations to novel stressors and to determine to what extent increased

  1. High false-positive rate of human immunodeficiency virus rapid serum screening in a predominantly hispanic prenatal population.

    Science.gov (United States)

    Zacharias, Nikolaos M; Athanassaki, Ioanna D; Sangi-Haghpeykar, Haleh; Gardner, Michael O

    2004-12-01

    To identify the characteristics of the gravidas delivering at our birthing center that place them at risk for false-positive human immunodeficiency virus (HIV) enzyme-linked immunosorbent assay (ELISA). The medical records of all rapid HIV-ELISA-positive gravidas that delivered at our hospital between January 2000 and October 2001 were retrieved, and information was gathered regarding maternal demographics. The results of the Western blot tests were also retrieved and correlated to the ELISA results, across varying maternal characteristics. chi(2), Student's t-test and multivariate analysis were performed, as appropriate, using the SAS software; statistical significance was denoted by ppositive rapid HIV-ELISA out of 9,781 deliveries. Of those, 26 were confirmed as HIV infected by Western blot (overall HIV prevalence: 0.27%, ELISA-positive predictive value: 37.7%). The subgroup prevalence of HIV and positive predictive value of ELISA were 1.53 and 75% among Caucasians; 2.43 and 82.6% among African-Americans; and 0.05 and 9.8% among Hispanics, respectively (p or =5 lifetime) sexual partners was elicited in the majority of HIV-infected patients. The positive predictive value of rapid HIV-ELISA during pregnancy varies widely, depending on maternal race/ethnicity and sexual behavior. The routine disclosure of rapid intrapartum HIV serum screening results prior to Western blot confirmation should be avoided in very low-risk populations.

  2. Late Pleistocene divergence and subsequent population expansion of two closely related fish species, Japanese anchovy (Engraulis japonicus) and Australian anchovy (Engraulis australis).

    Science.gov (United States)

    Liu, Jin-Xian; Gao, Tian-Xiang; Zhuang, Zhi-Meng; Jin, Xian-Shi; Yokogawa, Koji; Zhang, Ya-Ping

    2006-09-01

    Climatic oscillations during the Pleistocene ice ages produced great changes in species' geographical distribution and abundance, which could be expected to have genetic consequences. Living in the temperate upwelling zones of the northwestern Pacific, Japanese anchovy (Engraulis japonicus) might have been affected by these severe climatic oscillations. To investigate the effects of Pleistocene climatic changes on the evolution in Japanese anchovy, fragments of 522 bp at the 5' end of mitochondrial DNA control region were sequenced for 241 individuals from 13 localities and 37 individuals of Australian anchovy. Japanese anchovy and Australian anchovy are reciprocally monophyletic and a late Pleistocene transequatorial divergence between the two species was indicated. High levels of haplotype diversity (>0.99) were found for all samples, indicating a high level of genetic diversity. Analyses of molecular variance and the conventional population statistic F(ST) revealed no significant genetic structure throughout the range of Japanese anchovy. Both mismatch distribution analyses and neutrality tests suggested a late Pleistocene population expansion for both Japanese anchovy (79,000-317,000 years ago) and Australian anchovy (45,000-178,000 years ago).

  3. N-acetyl cysteine protects anti-melanoma cytotoxic T cells from exhaustion induced by rapid expansion via the downmodulation of Foxo1 in an Akt-dependent manner.

    Science.gov (United States)

    Scheffel, Matthew J; Scurti, Gina; Wyatt, Megan M; Garrett-Mayer, Elizabeth; Paulos, Chrystal M; Nishimura, Michael I; Voelkel-Johnson, Christina

    2018-02-02

    Therapeutic outcomes for adoptive cell transfer (ACT) therapy are constrained by the quality of the infused T cells. The rapid expansion necessary to obtain large numbers of cells results in a more terminally differentiated phenotype with decreased durability and functionality. N-acetyl cysteine (NAC) protects against activation-induced cell death (AICD) and improves anti-tumor efficacy of Pmel-1 T cells in vivo. Here, we show that these benefits of NAC can be extended to engineered T cells and significantly increases T-cell survival within the tumor microenvironment. The addition of NAC to the expansion protocol of human TIL13838I TCR-transduced T cells that are under evaluation in a Phase I clinical trial, demonstrated that findings in murine cells extend to human cells. Expansion of TIL13838I TCR-transduced T cells in NAC also increased their ability to kill target cells in vitro. Interestingly, NAC did not affect memory subsets, but diminished up-regulation of senescence (CD57) and exhaustion (PD-1) markers and significantly decreased expression of the transcription factors EOMES and Foxo1. Pharmacological inhibition of the PI3K/Akt pathway ablates the decrease in Foxo1 induced by NAC treatment of activated T cells. This suggests a model in which NAC through PI3K/Akt activation suppresses Foxo1 expression, thereby impacting its transcriptional targets EOMES, PD-1, and granzyme B. Taken together, our results indicate that NAC exerts pleiotropic effects that impact the quality of TCR-transduced T cells and suggest that the addition of NAC to current clinical protocols should be considered.

  4. Population genomics reveal recent speciation and rapid evolutionary adaptation in polar bears

    DEFF Research Database (Denmark)

    Liu, Shiping; Lorenzen, Eline D.; Fumagalli, Matteo

    2014-01-01

    Polar bears are uniquely adapted to life in the High Arctic and have undergone drastic physiological changes in response to Arctic climates and a hyperlipid diet of primarily marine mammal prey. We analyzed 89 complete genomes of polar bear and brown bear using population genomic modeling and show...

  5. Tissue-resident adult stem cell populations of rapidly self-renewing organs

    NARCIS (Netherlands)

    Barker, N.; Bartfeld, S.; Clevers, H.

    2010-01-01

    The epithelial lining of the intestine, stomach, and skin is continuously exposed to environmental assault, imposing a requirement for regular self-renewal. Resident adult stem cell populations drive this renewal, and much effort has been invested in revealing their identity. Reliable adult stem

  6. expansion method

    Indian Academy of Sciences (India)

    In this paper, we shall apply the (G /G)-expansion method to obtain the exact travelling wave solution of the two-dimensional ... In §3, we apply our method to the mentioned equations. In §4, some conclusions are ..... The exact solution obtained by this method can be used to check computer codes or as initial condition for ...

  7. Optical Coherence Tomography in the UK Biobank Study - Rapid Automated Analysis of Retinal Thickness for Large Population-Based Studies.

    Directory of Open Access Journals (Sweden)

    Pearse A Keane

    Full Text Available To describe an approach to the use of optical coherence tomography (OCT imaging in large, population-based studies, including methods for OCT image acquisition, storage, and the remote, rapid, automated analysis of retinal thickness.In UK Biobank, OCT images were acquired between 2009 and 2010 using a commercially available "spectral domain" OCT device (3D OCT-1000, Topcon. Images were obtained using a raster scan protocol, 6 mm x 6 mm in area, and consisting of 128 B-scans. OCT image sets were stored on UK Biobank servers in a central repository, adjacent to high performance computers. Rapid, automated analysis of retinal thickness was performed using custom image segmentation software developed by the Topcon Advanced Biomedical Imaging Laboratory (TABIL. This software employs dual-scale gradient information to allow for automated segmentation of nine intraretinal boundaries in a rapid fashion.67,321 participants (134,642 eyes in UK Biobank underwent OCT imaging of both eyes as part of the ocular module. 134,611 images were successfully processed with 31 images failing segmentation analysis due to corrupted OCT files or withdrawal of subject consent for UKBB study participation. Average time taken to call up an image from the database and complete segmentation analysis was approximately 120 seconds per data set per login, and analysis of the entire dataset was completed in approximately 28 days.We report an approach to the rapid, automated measurement of retinal thickness from nearly 140,000 OCT image sets from the UK Biobank. In the near future, these measurements will be publically available for utilization by researchers around the world, and thus for correlation with the wealth of other data collected in UK Biobank. The automated analysis approaches we describe may be of utility for future large population-based epidemiological studies, clinical trials, and screening programs that employ OCT imaging.

  8. Profiling of gene duplication patterns of sequenced teleost genomes: evidence for rapid lineage-specific genome expansion mediated by recent tandem duplications.

    Science.gov (United States)

    Lu, Jianguo; Peatman, Eric; Tang, Haibao; Lewis, Joshua; Liu, Zhanjiang

    2012-06-15

    Gene duplication has had a major impact on genome evolution. Localized (or tandem) duplication resulting from unequal crossing over and whole genome duplication are believed to be the two dominant mechanisms contributing to vertebrate genome evolution. While much scrutiny has been directed toward discerning patterns indicative of whole-genome duplication events in teleost species, less attention has been paid to the continuous nature of gene duplications and their impact on the size, gene content, functional diversity, and overall architecture of teleost genomes. Here, using a Markov clustering algorithm directed approach we catalogue and analyze patterns of gene duplication in the four model teleost species with chromosomal coordinates: zebrafish, medaka, stickleback, and Tetraodon. Our analyses based on set size, duplication type, synonymous substitution rate (Ks), and gene ontology emphasize shared and lineage-specific patterns of genome evolution via gene duplication. Most strikingly, our analyses highlight the extraordinary duplication and retention rate of recent duplicates in zebrafish and their likely role in the structural and functional expansion of the zebrafish genome. We find that the zebrafish genome is remarkable in its large number of duplicated genes, small duplicate set size, biased Ks distribution toward minimal mutational divergence, and proportion of tandem and intra-chromosomal duplicates when compared with the other teleost model genomes. The observed gene duplication patterns have played significant roles in shaping the architecture of teleost genomes and appear to have contributed to the recent functional diversification and divergence of important physiological processes in zebrafish. We have analyzed gene duplication patterns and duplication types among the available teleost genomes and found that a large number of genes were tandemly and intrachromosomally duplicated, suggesting their origin of independent and continuous duplication

  9. Correlations between Socioeconomic Drivers and Indicators of Urban Expansion: Evidence from the Heavily Urbanised Shanghai Metropolitan Area, China

    Directory of Open Access Journals (Sweden)

    Jinghui Li

    2017-07-01

    Full Text Available Rapid urban expansion resulting in increased impervious surfaces causes a series of urban environmental problems, e.g., the urban heat island and urban forest fragmentation. Urban expansion is a serious threat to human quality of life and living environments. It has been studied from a variety of aspects, but its driving factors and time series expansion characteristics (i.e., expansion intensity, pattern and direction need to be better explained in order to devise more effective management strategies. This study examined how social and economic factors are linked in driving urban expansion. Based on multi-temporal aerial images, a rapid urban expansion period, 2000–2010, in Shanghai was analysed. The urban area expanded from 1770.36 to 2855.44 km2 in the period, with a mean annual expansion rate of 108.51 km2. Urban expansion in 2000–2005 (40.42% was much faster than in 2005–2010 (14.86%, and its direction was southeast, southwest and south. The main pattern was edge expansion in both sub-periods. Social factors, especially population density, significantly affected urban expansion. These findings can help understand the urban expansion process and its driving factors, which has important implications for urban planning and management in Shanghai and similar cities.

  10. Monitoring the welfare of polar bear populations in a rapidly changing Arctic

    Science.gov (United States)

    Atwood, Todd C.; Duncan, Colleen G.; Patyk, Kelly A.; Sonsthagen, Sarah A.

    2017-01-01

    Most programs for monitoring the welfare of wildlife populations support efforts aimed at reaching discrete management objectives, like mitigating conflict with humans. While such programs can be effective, their limited scope may preclude systemic evaluations needed for large-scale conservation initiatives, like the recovery of at-risk species. We discuss select categories of metrics that can be used to monitor how polar bears (Ursus maritimus) are responding to the primary threat to their long-term persistence—loss of sea ice habitat due to the unabated rise in atmospheric greenhouse gas (GHG; e.g., CO2) concentrations—that can also provide information on ecosystem function and health. Monitoring key aspects of polar bear population dynamics, spatial behavior, health and resiliency can provide valuable insight into ecosystem state and function, and could be a powerful tool for achieving Arctic conservation objectives, particularly those that have transnational policy implications.

  11. Evolution of density-dependent movement during experimental range expansions.

    Science.gov (United States)

    Fronhofer, E A; Gut, S; Altermatt, F

    2017-12-01

    Range expansions and biological invasions are prime examples of transient processes that are likely impacted by rapid evolutionary changes. As a spatial process, range expansions are driven by dispersal and movement behaviour. Although it is widely accepted that dispersal and movement may be context-dependent, for instance density-dependent, and best represented by reaction norms, the evolution of density-dependent movement during range expansions has received little experimental attention. We therefore tested current theory predicting the evolution of increased movement at low densities at range margins using highly replicated and controlled range expansion experiments across multiple genotypes of the protist model system Tetrahymena thermophila. Although rare, we found evolutionary changes during range expansions even in the absence of initial standing genetic variation. Range expansions led to the evolution of negatively density-dependent movement at range margins. In addition, we report the evolution of increased intrastrain competitive ability and concurrently decreased population growth rates in range cores. Our findings highlight the importance of understanding movement and dispersal as evolving reaction norms and plastic life-history traits of central relevance for range expansions, biological invasions and the dynamics of spatially structured systems in general. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  12. Integrated care for older populations and its implementation facilitators and barriers: A rapid scoping review.

    Science.gov (United States)

    Threapleton, Diane E; Chung, Roger Y; Wong, Samuel Y S; Wong, Eliza; Chau, Patsy; Woo, Jean; Chung, Vincent C H; Yeoh, Eng-Kiong

    2017-06-01

    Inform health system improvements by summarizing components of integrated care in older populations. Identify key implementation barriers and facilitators. A scoping review was undertaken for evidence from MEDLINE, the Cochrane Library, organizational websites and internet searches. Eligible publications included reviews, reports, individual studies and policy documents published from 2005 to February 2017. Initial eligible documents were reviews or reports concerning integrated care approaches in older/frail populations. Other documents were later sourced to identify and contextualize implementation issues. Study findings and implementation barriers and facilitators were charted and thematically synthesized. Thematic synthesis using 30 publications identified 8 important components for integrated care in elderly and frail populations: (i) care continuity/transitions; (ii) enabling policies/governance; (iii) shared values/goals; (iv) person-centred care; (v) multi-/inter-disciplinary services; (vi) effective communication; (vii) case management; (viii) needs assessments for care and discharge planning. Intervention outcomes and implementation issues (barriers or facilitators) tend to depend heavily on the context and programme objectives. Implementation issues in four main areas were observed: (i) Macro-level contextual factors; (ii) Miso-level system organization (funding, leadership, service structure and culture); (iii) Miso-level intervention organization (characteristics, resources and credibility) and (iv) Micro-level factors (shared values, engagement and communication). Improving integration in care requires many components. However, local barriers and facilitators need to be considered. Changes are expected to occur slowly and are more likely to be successful where elements of integrated care are well incorporated into local settings.

  13. Population Genomics Reveal Recent Speciation and Rapid Evolutionary Adaptation in Polar Bears

    OpenAIRE

    Liu, Shiping; Lorenzen, Eline D.; Fumagalli, Matteo; Li, Bo; Harris, Kelley; Xiong, Zijun; ZHOU, Long; Korneliussen, Thorfinn Sand; Somel, Mehmet; Babbitt, Courtney; Wray, Greg; Li, Jianwen; He, Weiming; Wang, Zhuo; Fu, Wenjing

    2014-01-01

    Polar bears are uniquely adapted to life in the High Arctic and have undergone drastic physiological changes in response to Arctic climates and a hyperlipid diet of primarily marine mammal prey. We analyzed 89 complete genomes of polar bear and brown bear using population genomic modeling and show that the species diverged only 479–343 thousand years BP. We find that genes on the polar bear lineage have been under stronger positive selection than in brown bears; nine of the top 16 genes under...

  14. FREQ-Seq: a rapid, cost-effective, sequencing-based method to determine allele frequencies directly from mixed populations.

    Directory of Open Access Journals (Sweden)

    Lon M Chubiz

    Full Text Available Understanding evolutionary dynamics within microbial populations requires the ability to accurately follow allele frequencies through time. Here we present a rapid, cost-effective method (FREQ-Seq that leverages Illumina next-generation sequencing for localized, quantitative allele frequency detection. Analogous to RNA-Seq, FREQ-Seq relies upon counts from the >10(5 reads generated per locus per time-point to determine allele frequencies. Loci of interest are directly amplified from a mixed population via two rounds of PCR using inexpensive, user-designed oligonucleotides and a bar-coded bridging primer system that can be regenerated in-house. The resulting bar-coded PCR products contain the adapters needed for Illumina sequencing, eliminating further library preparation. We demonstrate the utility of FREQ-Seq by determining the order and dynamics of beneficial alleles that arose as a microbial population, founded with an engineered strain of Methylobacterium, evolved to grow on methanol. Quantifying allele frequencies with minimal bias down to 1% abundance allowed effective analysis of SNPs, small in-dels and insertions of transposable elements. Our data reveal large-scale clonal interference during the early stages of adaptation and illustrate the utility of FREQ-Seq as a cost-effective tool for tracking allele frequencies in populations.

  15. High resolution melting analytical platform for rapid prenatal and postnatal diagnosis of β-thalassemia common among Southeast Asian population.

    Science.gov (United States)

    Prajantasen, Thanet; Fucharoen, Supan; Fucharoen, Goonnapa

    2015-02-20

    High resolution melting (HRM) analysis is a powerful technology for scanning sequence alteration. We have applied this HRM assay to screen common β-thalassemia mutations found among Southeast Asian population. Known DNA samples with 8 common mutations were used in initial development of the methods including -28 A-G, codon 17 A-T, IVSI-1G-T, IVSI-5G-C, codon 26G-A (Hb E), codons 41/42 -TTCT, codons 71/72+A and IVSII-654 C-T. Further validation was done on 60 postnatal and 6 prenatal diagnoses of β-thalassemia. Each mutation has specific HRM profile which could be used in rapid screening. Apart from those with DNA deletions, the results of HRM assay matched 100% with those of routine diagnosis made by routine allele specific PCR. In addition, the HRM assay could initially recognize three unknown mutations including a hitherto un-described one in Thai population. The established HRM assay should prove useful for rapid and high throughput platform for screening and prenatal diagnosis of β-thalassemia common in the region. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Rapidly increasing body mass index among children, adolescents and young adults in a transitioning population, South Africa, 2008-15.

    Science.gov (United States)

    Sartorius, B; Sartorius, K; Taylor, M; Aagaard-Hansen, J; Dukhi, N; Day, C; Ndlovu, N; Slotow, R; Hofman, K

    2017-12-14

    There is a global epidemic of overweight and obesity; however, this rate of increase is even greater in some low- and middle-income countries (LMIC). South Africa (SA) is undergoing rapid socioeconomic and demographic changes that have triggered a rapid nutrition transition. The paper focuses on the recent rate of change of body mass index (BMI) among children, adolescents and young adults, further stratified by key sociodemographic factors. We analysed mean BMI of 28 247 individuals (including children) from 7301 households by age and year, from anthropometric data from four national cross-sectional (repeated panel) surveys using non-linear fitted curves and associated 95% confidence intervals. From 2008 to 2015, there was rapid rise in mean BMI in the 6-25 age band, with the highest risk (3-4+ BMI unit increase) among children aged 8-10 years. The increase was largely among females in urban areas and of middle-high socioeconomic standing. Prominent gains were also observed in certain rural areas, with extensive geographical heterogeneity across the country. We have demonstrated a major deviation from the current understanding of patterns of BMI increase, with a rate of increase substantially greater in the developing world context compared with the global pattern. This population-wide effect will have major consequences for national development as the epidemic of related non-communicable disease unfolds, and will overtax the national health care budget. Our refined understanding highlights that risks are further compounded for certain groups/places, and emphasizes that urgent geographical and population-targeted interventions are necessary. These interventions could include a sugar tax, clearer food labelling, revised school feeding programmes and mandatory bans on unhealthy food marketing to children.The scenario unfolding in South Africa will likely be followed in other LMICs.

  17. POPULATION GENOMICS REVEAL RECENT SPECIATION AND RAPID EVOLUTIONARY ADAPTATION IN POLAR BEARS

    Science.gov (United States)

    Liu, Shiping; Lorenzen, Eline D.; Fumagalli, Matteo; Li, Bo; Harris, Kelley; Xiong, Zijun; Zhou, Long; Korneliussen, Thorfinn Sand; Somel, Mehmet; Babbitt, Courtney; Wray, Greg; Li, Jianwen; He, Weiming; Wang, Zhuo; Fu, Wenjing; Xiang, Xueyan; Morgan, Claire C.; Doherty, Aoife; O’Connell, Mary J.; McInerney, James O.; Born, Erik W.; Dalén, Love; Dietz, Rune; Orlando, Ludovic; Sonne, Christian; Zhang, Guojie; Nielsen, Rasmus; Willerslev, Eske; Wang, Jun

    2014-01-01

    SUMMARY Polar bears are uniquely adapted to life in the High Arctic and have undergone drastic physiological changes in response to Arctic climates and a hyperlipid diet of primarily marine mammal prey. We analyzed 89 complete genomes of polar bear and brown bear using population genomic modeling and show that the species diverged only 479–343 thousand years BP. We find that genes on the polar bear lineage have been under stronger positive selection than in brown bears; nine of the top 16 genes under strong positive selection are associated with cardiomyopathy and vascular disease, implying important reorganization of the cardio-vascular system. One of the genes showing the strongest evidence of selection, APOB, encodes the primary lipoprotein component of low-density lipoprotein (LDL); functional mutations in APOB may explain how polar bears are able to cope with life-long elevated LDL levels that are associated with high risk of heart disease in humans. PMID:24813606

  18. Self-reported HIV-positive status but subsequent HIV-negative test result using rapid diagnostic testing algorithms among seven sub-Saharan African military populations.

    Directory of Open Access Journals (Sweden)

    Judith Harbertson

    Full Text Available HIV rapid diagnostic tests (RDTs combined in an algorithm are the current standard for HIV diagnosis in many sub-Saharan African countries, and extensive laboratory testing has confirmed HIV RDTs have excellent sensitivity and specificity. However, false-positive RDT algorithm results have been reported due to a variety of factors, such as suboptimal quality assurance procedures and inaccurate interpretation of results. We conducted HIV serosurveys in seven sub-Saharan African military populations and recorded the frequency of personnel self-reporting HIV positivity, but subsequently testing HIV-negative during the serosurvey. The frequency of individuals who reported they were HIV-positive but subsequently tested HIV-negative using RDT algorithms ranged from 3.3 to 91.1%, suggesting significant rates of prior false-positive HIV RDT algorithm results, which should be confirmed using biological testing across time in future studies. Simple measures could substantially reduce false-positive results, such as greater adherence to quality assurance guidelines and prevalence-specific HIV testing algorithms as described in the World Health Organization's HIV testing guidelines. Other measures to improve RDT algorithm specificity include classifying individuals with weakly positive test lines as HIV indeterminate and retesting. While expansion of HIV testing in resource-limited countries is critical to identifying HIV-infected individuals for appropriate care and treatment, careful attention to potential causes of false HIV-positive results are needed to prevent the significant medical, psychological, and fiscal costs resulting from individuals receiving a false-positive HIV diagnosis.

  19. Self-reported HIV-positive status but subsequent HIV-negative test result using rapid diagnostic testing algorithms among seven sub-Saharan African military populations.

    Science.gov (United States)

    Harbertson, Judith; Hale, Braden R; Tran, Bonnie R; Thomas, Anne G; Grillo, Michael P; Jacobs, Marni B; McAnany, Jennifer; Shaffer, Richard A

    2017-01-01

    HIV rapid diagnostic tests (RDTs) combined in an algorithm are the current standard for HIV diagnosis in many sub-Saharan African countries, and extensive laboratory testing has confirmed HIV RDTs have excellent sensitivity and specificity. However, false-positive RDT algorithm results have been reported due to a variety of factors, such as suboptimal quality assurance procedures and inaccurate interpretation of results. We conducted HIV serosurveys in seven sub-Saharan African military populations and recorded the frequency of personnel self-reporting HIV positivity, but subsequently testing HIV-negative during the serosurvey. The frequency of individuals who reported they were HIV-positive but subsequently tested HIV-negative using RDT algorithms ranged from 3.3 to 91.1%, suggesting significant rates of prior false-positive HIV RDT algorithm results, which should be confirmed using biological testing across time in future studies. Simple measures could substantially reduce false-positive results, such as greater adherence to quality assurance guidelines and prevalence-specific HIV testing algorithms as described in the World Health Organization's HIV testing guidelines. Other measures to improve RDT algorithm specificity include classifying individuals with weakly positive test lines as HIV indeterminate and retesting. While expansion of HIV testing in resource-limited countries is critical to identifying HIV-infected individuals for appropriate care and treatment, careful attention to potential causes of false HIV-positive results are needed to prevent the significant medical, psychological, and fiscal costs resulting from individuals receiving a false-positive HIV diagnosis.

  20. About Ganoderma boninense in oil palm plantations of Sumatra and peninsular Malaysia: Ancient population expansion, extensive gene flow and large scale dispersion ability.

    Science.gov (United States)

    Mercière, Maxime; Boulord, Romain; Carasco-Lacombe, Catherine; Klopp, Christophe; Lee, Yang-Ping; Tan, Joon-Sheong; Syed Alwee, Sharifah S R; Zaremski, Alba; De Franqueville, Hubert; Breton, Frédéric; Camus-Kulandaivelu, Létizia

    Wood rot fungi form one of the main classes of phytopathogenic fungus. The group includes many species, but has remained poorly studied. Many species belonging to the Ganoderma genus are well known for causing decay in a wide range of tree species around the world. Ganoderma boninense, causal agent of oil palm basal stem rot, is responsible for considerable yield losses in Southeast Asian oil palm plantations. In a large-scale sampling operation, 357 sporophores were collected from oil palm plantations spread over peninsular Malaysia and Sumatra and genotyped using 11 SSR markers. The genotyping of these samples made it possible to investigate the population structure and demographic history of G. boninense across the oldest known area of interaction between oil palm and G. boninense. Results show that G. boninense possesses a high degree of genetic diversity and no detectable genetic structure at the scale of Sumatra and peninsular Malaysia. The fact that few duplicate genotypes were found in several studies including this one supports the hypothesis of spore dispersal in the spread of G. boninense. Meanwhile, spatial autocorrelation analysis shows that G. boninense is able to disperse across both short and long distances. These results bring new insight into mechanisms by which G. boninense spreads in oil palm plantations. Finally, the use of approximate Bayesian computation (ABC) modelling indicates that G. boninense has undergone a demographic expansion in the past, probably before the oil palm was introduced into Southeast Asia. Copyright © 2017 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  1. Rapid growth and genetic diversity retention in an isolated reintroduced black bear population in the central appalachians

    Science.gov (United States)

    Murphy, Sean M.; Cox, John J.; Clark, Joseph D.; Augustine, Benjamin J.; Hast, John T.; Gibbs, Dan; Strunk, Michael; Dobey, Steven

    2015-01-01

    Animal reintroductions are important tools of wildlife management to restore species to their historical range, and they can also create unique opportunities to study population dynamics and genetics from founder events. We used non-invasive hair sampling in a systematic, closed-population capture-mark-recapture (CMR) study design at the Big South Fork (BSF) area in Kentucky during 2010 and Tennessee during 2012 to estimate the demographic and genetic characteristics of the black bear (Ursus americanus) population that resulted from a reintroduced founding population of 18 bears in 1998. We estimated 38 (95% CI: 31–66) and 190 (95% CI: 170–219) bears on the Kentucky and Tennessee study areas, respectively. Based on the Tennessee abundance estimate alone, the mean annual growth rate was 18.3% (95% CI: 17.4–19.5%) from 1998 to 2012. We also compared the genetic characteristics of bears sampled during 2010–2012 to bears in the population during 2000–2002, 2–4 years following reintroduction, and to the source population. We found that the level of genetic diversity since reintroduction as indicated by expected heterozygosity (HE) remained relatively constant (HE(source, 2004) = 0.763, HE(BSF, 2000–2002) = 0.729, HE(BSF, 2010–2012) = 0.712) and the effective number of breeders (NB) remained low but had increased since reintroduction in the absence of sufficient immigration (NB(BSF, 2000–2002) = 12, NB(BSF, 2010–2012)  = 35). This bear population appears to be genetically isolated, but contrary to our expectations, we did not find evidence of genetic diversity loss or other deleterious genetic effects typically observed from small founder groups. We attribute that to high initial genetic diversity in the founder group combined with overlapping generations and rapid population growth. Although the population remains relatively small, the reintroduction using a small founder group appears to be demographically and genetically

  2. Cognitive and clinical characteristics of patients with amyotrophic lateral sclerosis carrying a C9orf72 repeat expansion: a population-based cohort study.

    LENUS (Irish Health Repository)

    Byrne, Susan

    2012-03-01

    Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease of upper and lower motor neurons, associated with frontotemporal dementia (FTD) in about 14% of incident cases. We assessed the frequency of the recently identified C9orf72 repeat expansion in familial and apparently sporadic cases of ALS and characterised the cognitive and clinical phenotype of patients with this expansion.

  3. Population genomics reveal recent speciation and rapid evolutionary adaptation in polar bears.

    Science.gov (United States)

    Liu, Shiping; Lorenzen, Eline D; Fumagalli, Matteo; Li, Bo; Harris, Kelley; Xiong, Zijun; Zhou, Long; Korneliussen, Thorfinn Sand; Somel, Mehmet; Babbitt, Courtney; Wray, Greg; Li, Jianwen; He, Weiming; Wang, Zhuo; Fu, Wenjing; Xiang, Xueyan; Morgan, Claire C; Doherty, Aoife; O'Connell, Mary J; McInerney, James O; Born, Erik W; Dalén, Love; Dietz, Rune; Orlando, Ludovic; Sonne, Christian; Zhang, Guojie; Nielsen, Rasmus; Willerslev, Eske; Wang, Jun

    2014-05-08

    Polar bears are uniquely adapted to life in the High Arctic and have undergone drastic physiological changes in response to Arctic climates and a hyper-lipid diet of primarily marine mammal prey. We analyzed 89 complete genomes of polar bear and brown bear using population genomic modeling and show that the species diverged only 479-343 thousand years BP. We find that genes on the polar bear lineage have been under stronger positive selection than in brown bears; nine of the top 16 genes under strong positive selection are associated with cardiomyopathy and vascular disease, implying important reorganization of the cardiovascular system. One of the genes showing the strongest evidence of selection, APOB, encodes the primary lipoprotein component of low-density lipoprotein (LDL); functional mutations in APOB may explain how polar bears are able to cope with life-long elevated LDL levels that are associated with high risk of heart disease in humans. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Rapid identification of causal mutations in tomato EMS populations via mapping-by-sequencing.

    Science.gov (United States)

    Garcia, Virginie; Bres, Cécile; Just, Daniel; Fernandez, Lucie; Tai, Fabienne Wong Jun; Mauxion, Jean-Philippe; Le Paslier, Marie-Christine; Bérard, Aurélie; Brunel, Dominique; Aoki, Koh; Alseekh, Saleh; Fernie, Alisdair R; Fraser, Paul D; Rothan, Christophe

    2016-12-01

    The tomato is the model species of choice for fleshy fruit development and for the Solanaceae family. Ethyl methanesulfonate (EMS) mutants of tomato have already proven their utility for analysis of gene function in plants, leading to improved breeding stocks and superior tomato varieties. However, until recently, the identification of causal mutations that underlie particular phenotypes has been a very lengthy task that many laboratories could not afford because of spatial and technical limitations. Here, we describe a simple protocol for identifying causal mutations in tomato using a mapping-by-sequencing strategy. Plants displaying phenotypes of interest are first isolated by screening an EMS mutant collection generated in the miniature cultivar Micro-Tom. A recombinant F2 population is then produced by crossing the mutant with a wild-type (WT; non-mutagenized) genotype, and F2 segregants displaying the same phenotype are subsequently pooled. Finally, whole-genome sequencing and analysis of allele distributions in the pools allow for the identification of the causal mutation. The whole process, from the isolation of the tomato mutant to the identification of the causal mutation, takes 6-12 months. This strategy overcomes many previous limitations, is simple to use and can be applied in most laboratories with limited facilities for plant culture and genotyping.

  5. Rapid and sensitive magnetoelastic biosensors for the detection of Salmonella typhimurium in a mixed microbial population.

    Science.gov (United States)

    Guntupalli, R; Lakshmanan, R S; Hu, J; Huang, T S; Barbaree, J M; Vodyanoy, V; Chin, B A

    2007-07-01

    In this article, we report the results of an investigation into the performance of a wireless, magnetoelastic biosensor designed to selectively detect Salmonella typhimurium in a mixed microbial population. The Langmuir-Blodgett (LB) monolayer technique was employed for antibody (specific to Salmonella sp.) immobilization on rectangular shaped strip magnetoelastic sensors (2 x 0.4 x 0.015 mm). Bacterial binding to the antibody on the sensor surface changes the resonance parameters, and these changes were quantified as a shift in the sensor's resonance frequency. Response of the sensors to increasing concentrations (5 x 10(1) to 5 x 10(8) cfu/ml) of S. typhimurium in a mixture of extraneous foodborne pathogens (Escherichia coli O157:H7 and Listeria monocytogenes) was studied. A detection limit of 5 x 10(3) cfu/ml and a sensitivity of 139 Hz/decade were observed for the 2 x 0.4 x 0.015 mm sensors. Binding kinetics studies have shown that the dissociation constant (K(d)) and the binding valencies for water samples spiked with S. typhimurium was 435 cfu/ml and 2.33 respectively. The presence of extraneous microorganisms in the mixture did not produce an appreciable change in the biosensor's dose response behavior.

  6. Rapid and unambiguous detection of DNase I hypersensitive site in rare population of cells.

    Directory of Open Access Journals (Sweden)

    Wei-Ping Zeng

    Full Text Available DNase I hypersensitive (DHS sites are important for understanding cis regulation of gene expression. However, existing methods for detecting DHS sites in small numbers of cells can lead to ambiguous results. Here we describe a simple new method, in which DNA fragments with ends generated by DNase I digestion are isolated and used as templates for two PCR reactions. In the first PCR, primers are derived from sequences up- and down-stream of the DHS site. If the DHS site exists in the cells, the first PCR will not produce PCR products due to the cuts of the templates by DNase I between the primer sequences. In the second PCR, one primer is derived from sequence outside the DHS site and the other from the adaptor. This will produce a smear of PCR products of different sizes due to cuts by DNase I at different positions at the DHS site. With this design, we detected a DHS site at the CD4 gene in two CD4 T cell populations using as few as 2×10(4 cells. We further validated this method by detecting a DHS site of the IL-4 gene that is specifically present in type 2 but not type 1 T helper cells. Overall, this method overcomes the interference by genomic DNA not cut by DNase I at the DHS site, thereby offering unambiguous detection of DHS sites in the cells.

  7. Dynamic large-scale chromosomal rearrangements fuel rapid adaptation in yeast populations.

    Directory of Open Access Journals (Sweden)

    Shang-Lin Chang

    Full Text Available Large-scale genome rearrangements have been observed in cells adapting to various selective conditions during laboratory evolution experiments. However, it remains unclear whether these types of mutations can be stably maintained in populations and how they impact the evolutionary trajectories. Here we show that chromosomal rearrangements contribute to extremely high copper tolerance in a set of natural yeast strains isolated from Evolution Canyon (EC, Israel. The chromosomal rearrangements in EC strains result in segmental duplications in chromosomes 7 and 8, which increase the copy number of genes involved in copper regulation, including the crucial transcriptional activator CUP2 and the metallothionein CUP1. The copy number of CUP2 is correlated with the level of copper tolerance, indicating that increasing dosages of a single transcriptional activator by chromosomal rearrangements has a profound effect on a regulatory pathway. By gene expression analysis and functional assays, we identified three previously unknown downstream targets of CUP2: PHO84, SCM4, and CIN2, all of which contributed to copper tolerance in EC strains. Finally, we conducted an evolution experiment to examine how cells maintained these changes in a fluctuating environment. Interestingly, the rearranged chromosomes were reverted back to the wild-type configuration at a high frequency and the recovered chromosome became fixed in less selective conditions. Our results suggest that transposon-mediated chromosomal rearrangements can be highly dynamic and can serve as a reversible mechanism during early stages of adaptive evolution.

  8. Avaliação da expansão rápida da maxila por meio da tomografia computadorizada: relato de um caso Computed tomography evaluation of rapid maxillary expansion: a case report

    Directory of Open Access Journals (Sweden)

    Daniela Gamba Garib

    2005-08-01

    Full Text Available Este trabalho descreve os efeitos dentoesqueléticos e periodontais da expansão rápida da maxila (ERM, avaliados por meio da tomografia computadorizada (TC, em uma jovem de 11,6 anos de idade com má oclusão de Classe I e mordida cruzada posterior unilateral funcional. Durante a fase ativa da ERM, o expansor dentossuportado com parafuso Hyrax foi ativado 7mm. A paciente submeteu-se ao exame de TC helicoidal, antes da expansão e após a remoção do aparelho expansor, findo o período de três meses de contenção. Realizaram-se cortes axiais, de um milímetro de espessura, paralelamente ao plano palatino, englobando as regiões dentoalveolar e basal da maxila, até o terço inferior da cavidade nasal. Utilizando-se o recurso de reconstruções multiplanares, mensuraram-se pelo método computadorizado: as dimensões transversas maxilares, a inclinação dos dentes posteriores, a espessura das tábuas ósseas vestibular e lingual, e o nível da crista óssea alveolar vestibular. A expansão rápida da maaxila ocasionou um significante aumento transverso em todas as regiões aferidas, com magnitude decrescente do arco dentário para a base óssea. Os dentes posteriores foram movimentados para vestibular, com um componente de inclinação e translação associados. Tal efeito ortodôntico ocasionou uma redução na espessura da tábua óssea vestibular, e um concomitante aumento na espessura da tábua óssea lingual. Após a expansão, observou-se o desenvolvimento de deiscências ósseas por vestibular dos dentes de ancoragem.This paper presents a computed tomography (CT evaluation of rapid maxillary expansion dentoskeletal and periodontal effects, in a 11.6 year-old girl presenting Class I malocclusion with posterior unilateral crossbite. The tooth-borne expander with Hyrax screw was activated 7-mm. The patient was submitted to helicoidal CT scan before expansion and after the three-month retention period when the expander was removed. Axial

  9. Genetic analysis of morphological traits in a new, versatile, rapid-cycling Brassica rapa recombinant inbred line population

    Science.gov (United States)

    Bagheri, Hedayat; El-Soda, Mohamed; van Oorschot, Inge; Hanhart, Corrie; Bonnema, Guusje; Jansen-van den Bosch, Tanja; Mank, Rolf; Keurentjes, Joost J. B.; Meng, Lin; Wu, Jian; Koornneef, Maarten; Aarts, Mark G. M.

    2012-01-01

    A recombinant inbred line (RIL) population was produced based on a wide cross between the rapid-cycling and self-compatible genotypes L58, a Caixin vegetable type, and R-o-18, a yellow sarson oil type. A linkage map based on 160 F7 lines was constructed using 100 Single nucleotide polymorphisms (SNPs), 130 AFLP®, 27 InDel, and 13 publicly available SSR markers. The map covers a total length of 1150 centiMorgan (cM) with an average resolution of 4.3 cM/marker. To demonstrate the versatility of this new population, 17 traits, related to plant architecture and seed characteristics, were subjected to quantitative trait loci (QTL) analysis. A total of 47 QTLs were detected, each explaining between 6 and 54% of the total phenotypic variance for the concerned trait. The genetic analysis shows that this population is a useful new tool for analyzing genetic variation for interesting traits in B. rapa, and for further exploitation of the recent availability of the B. rapa whole genome sequence for gene cloning and gene function analysis. PMID:22912644

  10. Genetic analysis of morphological traits in a new, versatile, rapid-cycling Brassica rapa recombinant inbred line population

    Directory of Open Access Journals (Sweden)

    Hedayat eBagheri

    2012-08-01

    Full Text Available A recombinant inbred line (RIL population was produced based on a wide cross between the rapid-cycling and self-compatible genotypes L58, a Caixin vegetable type, and R-o-18, a yellow sarson oil type. A linkage map based on 160 F7 lines was constructed using 100 SNP, 130 AFLP®, 27 InDel and 13 publicly available SSR markers. The map covers a total length of 1150 cM with an average resolution of 4.3 cM/marker. To demonstrate the versatility of this new population, 17 traits, related to plant architecture and seed characteristics, were subjected to QTL analysis. A total of 47 QTLs were detected, each explaining between 6 to 54% of the total phenotypic variance for the concerned trait. The genetic analysis shows that this population is a useful new tool for analyzing genetic variation for interesting traits in B. rapa, and for further exploitation of the recent availability of the B. rapa whole genome sequence for gene cloning and gene function analysis.

  11. Influence of rapid rural-urban population migration on riverine nitrogen pollution: perspective from ammonia-nitrogen.

    Science.gov (United States)

    Zhang, Wangshou; Swaney, Dennis P; Hong, Bongghi; Howarth, Robert W; Li, Xuyong

    2017-09-30

    China is undergoing a rapid transition from a rural to an urban society. This societal change is a consequence of a national drive toward economic prosperity. However, accelerated urban development resulting from rapid population migration from rural to urban lands has led to high levels of untreated sewage entering aquatic ecosystems directly. Consequently, many of these regions have been identified as hot spots of riverine nitrogen (N) pollution because of the increasing level of urban point-source discharge. In order to address this concern, we assessed effects of urban development on ammonia-nitrogen (AN) loads using a panel data regression model. The model, expressed as an exponential function of anthropogenic N inputs multiplied by a power function of streamflow, was applied to 20 subwatersheds of the Huai River Basin for the years 2003-2010. The results indicated that this model can account for 81% of the variation in annual AN fluxes over space and time. Application of this model to three scenarios of urban development and sewage treatment (termed urbanization priority, sustainable development, and environmental priority) suggests that future N pollution will inevitably deteriorate if current urban environmental management and investment are not significantly improved. Stronger support for environmental management is very critical to alleviate N pollution and improve water quality. More effort should focus on improving sewage treatment and the N removal rate of the current sewage system in light of the increasing degree of urbanization.

  12. Population Divergence in Venom Bioactivities of Elapid Snake Pseudonaja textilis: Role of Procoagulant Proteins in Rapid Rodent Prey Incapacitation

    Science.gov (United States)

    Skejić, Jure; Hodgson, Wayne C.

    2013-01-01

    This study looked at how toxic proteins in venoms of adult Australian eastern Brown snakes Pseudonaja textilis from South Australian and Queensland populations interact with physiological functions of the lab SD rat Rattus norvegicus. Circulatory collapse and incoagulable blood occurred instantly after injection of venom under the dorsal skin of anaesthetised and mechanically ventilated rats in an imitation of a P. textilis bite. Intravenous injection of purified P. textilis (Mackay, QLD) venom prothrombin activator proteins caused instant failure of circulation, testifying of high toxicity of these proteins and suggesting their role in rapid incapacitation of rodent prey. The hypothesis is further supported by circulatory collapse occurring instantly despite artificial respiration in envenomed rats and the finding of extremely high venom procoagulant potency in rat plasma. LC-MS and physiology assays revealed divergent venom composition and biological activity of South Australian (Barossa locality) and Queensland (Mackay locality) populations, which may be driven by selection for different prey. The Queensland venom of P. textilis was found to be more procoagulant and to exhibit predominately presynaptic neurotoxicity, while the South Australian venom contained diverse postsynaptic type II and III α-neurotoxins in addition to the presynaptic neurotoxins and caused significantly faster onset of neuromuscular blockade in the rat phrenic nerve-diaphragm preparation. LC-MS analysis found evidence of multiple coagulation factor X-like proteins in P. textilis venoms, including a match to P. textilis coagulation factor X isoform 2, previously known to be expressed only in the liver. PMID:23691135

  13. Rapidly rising incidence of childhood type 1 diabetes in Chinese population: epidemiology in Shanghai during 1997-2011.

    Science.gov (United States)

    Zhao, Zhuhui; Sun, Chengjun; Wang, Chunfang; Li, Pin; Wang, Wei; Ye, Jun; Gu, Xuefan; Wang, Xiaodong; Shen, Shuixian; Zhi, Dijing; Lu, Zhong; Ye, Rong; Cheng, Ruoqian; Xi, Li; Li, Xiaojing; Zheng, Zhangqian; Zhang, Miaoying; Luo, Feihong

    2014-12-01

    The aim of this study was to investigate incidence trend of childhood type 1 diabetes in Shanghai, a megalopolis in east China. We established a population-based retrospective registry for the disease in the city's registered population during 1997-2011 and collected 622 incident type 1 diabetes in children aged 0-14 years. Standardized incidence rates and 95 % CI were estimated by applying the capture-recapture method and assuming Poisson distribution. Incidence trend was analyzed using the Poisson regression model. The mean annual incidence of childhood type 1 diabetes was 3.1 per 100,000 person-years. We did not observe significant difference in incidence between boys and girls. The incidence is unstable and had a mean annual increase 14.2 % per year during the studied period. A faster annual increase was observed in boys, warmer seasons, and in the outer regions of the city. If present trends continue, the number of new type 1 diabetes cases will double from 2016 to 2020, and prevalent cases will sextuple by 2025. Our results showed the incidence of childhood type 1 diabetes was rising rapidly in Shanghai. More studies are needed to analyze incidence changes in other regions of China for appropriate allocation of healthcare resources.

  14. Population divergence in venom bioactivities of elapid snake Pseudonaja textilis: role of procoagulant proteins in rapid rodent prey incapacitation.

    Directory of Open Access Journals (Sweden)

    Jure Skejić

    Full Text Available This study looked at how toxic proteins in venoms of adult Australian eastern Brown snakes Pseudonaja textilis from South Australian and Queensland populations interact with physiological functions of the lab SD rat Rattus norvegicus. Circulatory collapse and incoagulable blood occurred instantly after injection of venom under the dorsal skin of anaesthetised and mechanically ventilated rats in an imitation of a P. textilis bite. Intravenous injection of purified P. textilis (Mackay, QLD venom prothrombin activator proteins caused instant failure of circulation, testifying of high toxicity of these proteins and suggesting their role in rapid incapacitation of rodent prey. The hypothesis is further supported by circulatory collapse occurring instantly despite artificial respiration in envenomed rats and the finding of extremely high venom procoagulant potency in rat plasma. LC-MS and physiology assays revealed divergent venom composition and biological activity of South Australian (Barossa locality and Queensland (Mackay locality populations, which may be driven by selection for different prey. The Queensland venom of P. textilis was found to be more procoagulant and to exhibit predominately presynaptic neurotoxicity, while the South Australian venom contained diverse postsynaptic type II and III α-neurotoxins in addition to the presynaptic neurotoxins and caused significantly faster onset of neuromuscular blockade in the rat phrenic nerve-diaphragm preparation. LC-MS analysis found evidence of multiple coagulation factor X-like proteins in P. textilis venoms, including a match to P. textilis coagulation factor X isoform 2, previously known to be expressed only in the liver.

  15. Rapid changes in transcription profiles of the Plasmodium yoelii yir multigene family in clonal populations: lack of epigenetic memory?

    Directory of Open Access Journals (Sweden)

    Deirdre Cunningham

    Full Text Available The pir multigene family, found in the genomes of Plasmodium vivax, P. knowlesi and the rodent malaria species, encode variant antigens that could be targets of the immune response. Individual parasites of the rodent malaria Plasmodium yoelii, selected by micromanipulation, transcribe only 1 to 3 different pir (yir suggesting tight transcriptional control at the level of individual cells. Using microarray and quantitative RT-PCR, we show that despite this very restricted transcription in a single cell, many yir genes are transcribed throughout the intra-erythrocytic asexual cycle. The timing and level of transcription differs between genes, with some being more highly transcribed in ring and trophozoite stages, whereas others are more highly transcribed in schizonts. Infection of immunodeficient mice with single infected erythrocytes results in populations of parasites each with transcriptional profiles different from that of the parent parasite population and from each other. This drift away from the original 'set' of transcribed genes does not appear to follow a preset pattern and "epigenetic memory" of the yir transcribed in the parent parasite can be rapidly lost. Thus, regulation of pir gene transcription may be different from that of the well-characterised multigene family, var, of Plasmodium falciparum.

  16. Rapid changes in transcription profiles of the Plasmodium yoelii yir multigene family in clonal populations: lack of epigenetic memory?

    Science.gov (United States)

    Cunningham, Deirdre; Fonager, Jannik; Jarra, William; Carret, Celine; Preiser, Peter; Langhorne, Jean

    2009-01-01

    The pir multigene family, found in the genomes of Plasmodium vivax, P. knowlesi and the rodent malaria species, encode variant antigens that could be targets of the immune response. Individual parasites of the rodent malaria Plasmodium yoelii, selected by micromanipulation, transcribe only 1 to 3 different pir (yir) suggesting tight transcriptional control at the level of individual cells. Using microarray and quantitative RT-PCR, we show that despite this very restricted transcription in a single cell, many yir genes are transcribed throughout the intra-erythrocytic asexual cycle. The timing and level of transcription differs between genes, with some being more highly transcribed in ring and trophozoite stages, whereas others are more highly transcribed in schizonts. Infection of immunodeficient mice with single infected erythrocytes results in populations of parasites each with transcriptional profiles different from that of the parent parasite population and from each other. This drift away from the original 'set' of transcribed genes does not appear to follow a preset pattern and "epigenetic memory" of the yir transcribed in the parent parasite can be rapidly lost. Thus, regulation of pir gene transcription may be different from that of the well-characterised multigene family, var, of Plasmodium falciparum.

  17. [Rapid maxillary expansion: clinical and radiographic principles].

    Science.gov (United States)

    dos Santos-Pinto, C C; Henriques, J F

    1990-01-01

    The midpalatine suture disjunction as an auxiliary means in the treatment of malocclusions with horizontal craneal base deficiencies has become a routine procedure in the orthodontic clinic. Therefore, for it to become an adequate therapeutical procedure for our patients it is of upmost importance we make a radiographic examinative so that we may juntify our diagnosis in that refers to facial skeletal disharmonies, specially in horizontal maxilary discrepancies.

  18. Genome-wide identification and comparative expression analysis reveal a rapid expansion and functional divergence of duplicated genes in the WRKY gene family of cabbage, Brassica oleracea var. capitata.

    Science.gov (United States)

    Yao, Qiu-Yang; Xia, En-Hua; Liu, Fei-Hu; Gao, Li-Zhi

    2015-02-15

    WRKY transcription factors (TFs), one of the ten largest TF families in higher plants, play important roles in regulating plant development and resistance. To date, little is known about the WRKY TF family in Brassica oleracea. Recently, the completed genome sequence of cabbage (B. oleracea var. capitata) allows us to systematically analyze WRKY genes in this species. A total of 148 WRKY genes were characterized and classified into seven subgroups that belong to three major groups. Phylogenetic and synteny analyses revealed that the repertoire of cabbage WRKY genes was derived from a common ancestor shared with Arabidopsis thaliana. The B. oleracea WRKY genes were found to be preferentially retained after the whole-genome triplication (WGT) event in its recent ancestor, suggesting that the WGT event had largely contributed to a rapid expansion of the WRKY gene family in B. oleracea. The analysis of RNA-Seq data from various tissues (i.e., roots, stems, leaves, buds, flowers and siliques) revealed that most of the identified WRKY genes were positively expressed in cabbage, and a large portion of them exhibited patterns of differential and tissue-specific expression, demonstrating that these gene members might play essential roles in plant developmental processes. Comparative analysis of the expression level among duplicated genes showed that gene expression divergence was evidently presented among cabbage WRKY paralogs, indicating functional divergence of these duplicated WRKY genes. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Rapid evolution in the wild: changes in body size, life-history traits, and behavior in hunted populations of the Japanese mamushi snake.

    Science.gov (United States)

    Sasaki, Kiyoshi; Fox, Stanley F; Duvall, David

    2009-02-01

    Rapid evolution caused by human exploitation of wildlife is not usually addressed in studies of the impacts of such exploitation despite its direct relevance to population persistence. Japanese mamushi (Gloydius blomhoffii), an endemic venomous snake of the Japanese archipelago, has been heavily hunted by humans, and many populations appear to be declining or are already extirpated. We compared local populations that have been hunted regularly with populations that have not been hunted. Mamushi in hunted populations were smaller, had fewer vertebrae, produced more and smaller offspring, had increased reproductive effort among smaller females, and in nature fled at greater distances from an approaching human and were less defensive than mamushi in unhunted populations, as predicted from life-history theory. Heritability estimates for body size, number of vertebrae, and antipredator behavior were statistically significant, and neonates from hunted sites showed the same distribution of altered characters (compared with those from unhunted sites) as adults. Thus, distribution of the divergent trait between hunted and unhunted sites appeared in part to be genetically based, which suggests rapid evolution to human predation pressures. Trait distributions in hunted populations probably deviate from naturally (as opposed to anthropogenically) selected optima and, therefore, may have long-term negative repercussions on population persistence. Because rapid evolution affects a suite of parameters that characterize exploited populations, accurate understanding of the impacts of exploitation and effective resource management and conservation can only be achieved if evolutionary consequences are considered explicitly.

  20. Limnological regime shifts caused by climate warming and Lesser Snow Goose population expansion in the western Hudson Bay Lowlands (Manitoba, Canada).

    Science.gov (United States)

    MacDonald, Lauren A; Farquharson, Nicole; Merritt, Gillian; Fooks, Sam; Medeiros, Andrew S; Hall, Roland I; Wolfe, Brent B; Macrae, Merrin L; Sweetman, Jon N

    2015-02-01

    Shallow lakes are dominant features in subarctic and Arctic landscapes and are responsive to multiple stressors, which can lead to rapid changes in limnological regimes with consequences for aquatic resources. We address this theme in the coastal tundra region of Wapusk National Park, western Hudson Bay Lowlands (Canada), where climate has warmed during the past century and the Lesser Snow Goose (LSG; Chen caerulescens caerulescens) population has grown rapidly during the past ∽40 years. Integration of limnological and paleolimnological analyses documents profound responses of productivity, nutrient cycling, and aquatic habitat to warming at three ponds ("WAP 12", "WAP 20", and "WAP 21″), and to LSG disturbance at the two ponds located in an active nesting area (WAP 20, WAP 21). Based on multiparameter analysis of (210)Pb-dated sediment records from all three ponds, a regime shift occurred between 1875 and 1900 CE marked by a transition from low productivity, turbid, and nutrient-poor conditions of the Little Ice Age to conditions of higher productivity, lower nitrogen availability, and the development of benthic biofilm habitat as a result of climate warming. Beginning in the mid-1970s, sediment records from WAP 20 and WAP 21 reveal a second regime shift characterized by accelerated productivity and increased nitrogen availability. Coupled with 3 years of limnological data, results suggest that increased productivity at WAP 20 and WAP 21 led to atmospheric CO2 invasion to meet algal photosynthetic demand. This limnological regime shift is attributed to an increase in the supply of catchment-derived nutrients from the arrival of LSG and their subsequent disturbance to the landscape. Collectively, findings discriminate the consequences of warming and LSG disturbance on tundra ponds from which we identify a suite of sensitive limnological and paleolimnological measures that can be utilized to inform aquatic ecosystem monitoring.

  1. Rapid approach to the quantitative determination of nocturnal ground irradiance in populated territories: a clear-sky case

    Science.gov (United States)

    Kocifaj, Miroslav; Petržala, Jaromír

    2016-11-01

    A zero-order approach to the solving of the radiative transfer equation and a method for obtaining the horizontal diffuse irradiance at night-time are both developed and intended for wide use in numerical predictions of nocturnal ground irradiance in populated territories. Downward diffuse radiative fluxes are computed with a two-stream approximation, and the data products obtained are useful for scientists who require rapid estimations of illumination levels during the night. The rapid technique presented here is especially important when the entire set of calculations is to be repeated for different lighting technologies and/or radiant intensity distributions with the aim of identifying high-level illuminance/irradiance, the spectral composition of scattered light or other optical properties of diffuse light at the ground level. The model allows for the computation of diffuse horizontal irradiance due to light emissions from ground-based sources with arbitrary spectral compositions. The optical response of a night sky is investigated using the ratio of downward to upward irradiance, R⊥, λ(0). We show that R⊥, λ(0) generally peaks at short wavelengths, thus suggesting that, e.g., the blue light of an LED lamp would make the sky even more bluish. However, this effect can be largely suppressed or even removed with the spectral sensitivity function of the average human eye superimposed on to the lamp spectrum. Basically, blue light scattering dominates at short optical distances, while red light is transmitted for longer distances and illuminates distant places. Computations are performed for unshielded as well as fully shielded lights, while the spectral function R⊥, λ(0) is tabulated to make possible the modelling of various artificial lights, including those not presented here.

  2. Estimates of expansion time scales

    Science.gov (United States)

    Jones, E. M.

    Monte Carlo simulations of the expansion of a spacefaring civilization show that descendants of that civilization should be found near virtually every useful star in the Galaxy in a time much less than the current age of the Galaxy. Only extreme assumptions about local population growth rates, emigration rates, or ship ranges can slow or halt an expansion. The apparent absence of extraterrestrials from the solar system suggests that no such civilization has arisen in the Galaxy.

  3. Avaliação cefalométrica da estabilidade pós-expansão rápida da maxila assistida cirurgicamente Cephalometric evaluation of the post surgically assisted rapid maxillary expansion stability

    Directory of Open Access Journals (Sweden)

    Pedro Luis Scattaregi

    2009-10-01

    Full Text Available OBJETIVO: avaliar as possíveis alterações e a estabilidade dentária e esquelética no sentido transversal, bem como as possíveis alterações verticais da face (AFAI, produzidas pela Expansão Rápida da Maxila Assistida Cirurgicamente (ERMAC. MÉTODOS: a amostra selecionada para este estudo retrospectivo foi composta por 60 telerradiografias em norma frontal, de 15 pacientes, sendo 6 do gênero masculino e 9 do gênero feminino, com média de idades de 23 anos e 3 meses. O disjuntor Hyrax foi instalado e o procedimento cirúrgico adotado envolveu a separação da sutura palatina mediana e não-abordagem da sutura pterigomaxilar. A ativação foi realizada do terceiro dias após a cirurgia até o término da expansão, determinada por critérios clínicos. Todos os pacientes foram radiografados nas fases pré-expansão (T1; pós-expansão imediata (T2; 3 meses pós-expansão, com o próprio disjuntor como contenção (T3; e 6 meses pós-expansão, com a placa removível de acrílico como contenção (T4. Medidas lineares foram obtidas a partir dos traçados cefalométricos gerados por um programa computadorizado (Radiocef Studio 2 e analisadas estatisticamente pelos testes de variância (ANOVA e Tukey ao nível de 5% de significância. RESULTADOS E CONCLUSÕES: concluiu-se que a ERMAC produziu aumentos estatisticamente significativos da cavidade nasal, da largura maxilar e da distância intermolares superiores, de T1 para T2, os quais se mantiveram em T3 e T4. A largura facial e as distâncias intermolares inferiores não apresentaram alterações após a ERMAC. Avaliando o comportamento vertical da face, notou-se um aumento da AFAI nas fases T1 para T2, que diminuiu após a contenção de 3 meses (T3 e permaneceu estável em T4, embora aumentada se comparada com T1.AIM: This study evaluated the stability of the dental and skeletal changes produced by the Surgically Assisted Rapid Maxillary Expansion (SARME in transversal and vertical

  4. BREATHING FIRE: HOW STELLAR FEEDBACK DRIVES RADIAL MIGRATION, RAPID SIZE FLUCTUATIONS, AND POPULATION GRADIENTS IN LOW-MASS GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    El-Badry, Kareem; Geha, Marla [Department of Astronomy, Yale University, New Haven, CT (United States); Wetzel, Andrew; Hopkins, Philip F. [TAPIR, California Institute of Technology, Pasadena, CA USA (United States); Kereš, Dusan; Chan, T. K. [Department of Physics, Center for Astrophysics and Space Sciences, University of California at San Diego, La Jolla (United States); Faucher-Giguère, Claude-André, E-mail: kareem.el-badry@yale.edu [Department of Physics and Astronomy and CIERA, Northwestern University, Evanston, IL (United States)

    2016-04-01

    We examine the effects of stellar feedback and bursty star formation on low-mass galaxies (M{sub star} = 2 × 10{sup 6} − 5 × 10{sup 10} M{sub ⊙}) using the Feedback in Realistic Environments (FIRE) simulations. While previous studies emphasized the impact of feedback on dark matter profiles, we investigate the impact on the stellar component: kinematics, radial migration, size evolution, and population gradients. Feedback-driven outflows/inflows drive significant radial stellar migration over both short and long timescales via two processes: (1) outflowing/infalling gas can remain star-forming, producing young stars that migrate ∼1 kpc within their first 100 Myr, and (2) gas outflows/inflows drive strong fluctuations in the global potential, transferring energy to all stars. These processes produce several dramatic effects. First, galaxies’ effective radii can fluctuate by factors of >2 over ∼200 Myr, and these rapid size fluctuations can account for much of the observed scatter in the radius at fixed M{sub star}. Second, the cumulative effects of many outflow/infall episodes steadily heat stellar orbits, causing old stars to migrate outward most strongly. This age-dependent radial migration mixes—and even inverts—intrinsic age and metallicity gradients. Thus, the galactic-archaeology approach of calculating radial star formation histories from stellar populations at z = 0 can be severely biased. These effects are strongest at M{sub star} ≈ 10{sup 7–9.6} M{sub ⊙}, the same regime where feedback most efficiently cores galaxies. Thus, detailed measurements of stellar kinematics in low-mass galaxies can strongly constrain feedback models and test baryonic solutions to small-scale problems in ΛCDM.

  5. Highways block gene flow and cause a rapid decline in genetic diversity of desert bighorn sheep

    NARCIS (Netherlands)

    Epps, CW; Palsboll, PJ; Wehausen, JD; Roderick, GK; Ramey, RR; McCullough, DR

    2005-01-01

    The rapid expansion of road networks has reduced connectivity among populations of flora and fauna. The resulting isolation is assumed to increase population extinction rates, in part because of the loss of genetic diversity. However, there are few cases where loss of genetic diversity has been

  6. Three-Dimensional Evaluation of the Upper Airway Morphological Changes in Growing Patients with Skeletal Class III Malocclusion Treated by Protraction Headgear and Rapid Palatal Expansion: A Comparative Research.

    Directory of Open Access Journals (Sweden)

    Xueling Chen

    Full Text Available The aim of this study was to evaluate the morphological changes of upper airway after protraction headgear and rapid maxillary expansion (PE treatment in growing patients with Class III malocclusion and maxillary skeletal deficiency compared with untreated Class III patients by cone-beam computed tomography (CBCT.Thirty growing patients who have completed PE therapy were included in PE group. The control group (n = 30 was selected from the growing untreated patients with the same diagnosis. The CBCT scans of the pre-treatment (T1 and post-treatment (T2 of PE group and the control group were collected. Reconstruction and registration of the 3D models of T1 and T2 were completed. By comparing the data obtained from T1, T2 and control group, the morphological changes of the upper airway during the PE treatment were evaluated.Comparing with the data from T1 group, the subspinale (A of maxilla and the upper incisor (UI of the T2 group were moved in the anterior direction. The gnathion (Gn of mandible was moved in the posterior-inferior direction. The displacement of the hyoid bone as well as the length and width of dental arch showed significant difference. The volume and mean cross-sectional area of nasopharynx, velopharynx and glossopharynx region showed significant difference. The largest anteroposterior/the largest lateral (AP/LR ratios of the velopharynx and glossopharynx were increased, but the AP/LR ratio of the hypopharynx was decreased. In addition, the length and width of the maxillary dental arch, the displacement of the hyoid bone, the volume of nasopharynx and velopharynx, and the AP/LR ratio of the hypopharynx and velopharynx showed significant difference between the data from control and T2 group.The PE treatment of Class III malocclusion with maxillary skeletal hypoplasia leads to a significant increase in the volume of nasopharynx and velopharynx.

  7. Three-Dimensional Evaluation of the Upper Airway Morphological Changes in Growing Patients with Skeletal Class III Malocclusion Treated by Protraction Headgear and Rapid Palatal Expansion: A Comparative Research.

    Science.gov (United States)

    Chen, Xueling; Liu, Dongxu; Liu, Ju; Wu, Zizhong; Xie, Yongtao; Li, Liang; Liu, Hong; Guo, Tiantian; Chen, Chen; Zhang, Shijie

    2015-01-01

    The aim of this study was to evaluate the morphological changes of upper airway after protraction headgear and rapid maxillary expansion (PE) treatment in growing patients with Class III malocclusion and maxillary skeletal deficiency compared with untreated Class III patients by cone-beam computed tomography (CBCT). Thirty growing patients who have completed PE therapy were included in PE group. The control group (n = 30) was selected from the growing untreated patients with the same diagnosis. The CBCT scans of the pre-treatment (T1) and post-treatment (T2) of PE group and the control group were collected. Reconstruction and registration of the 3D models of T1 and T2 were completed. By comparing the data obtained from T1, T2 and control group, the morphological changes of the upper airway during the PE treatment were evaluated. Comparing with the data from T1 group, the subspinale (A) of maxilla and the upper incisor (UI) of the T2 group were moved in the anterior direction. The gnathion (Gn) of mandible was moved in the posterior-inferior direction. The displacement of the hyoid bone as well as the length and width of dental arch showed significant difference. The volume and mean cross-sectional area of nasopharynx, velopharynx and glossopharynx region showed significant difference. The largest anteroposterior/the largest lateral (AP/LR) ratios of the velopharynx and glossopharynx were increased, but the AP/LR ratio of the hypopharynx was decreased. In addition, the length and width of the maxillary dental arch, the displacement of the hyoid bone, the volume of nasopharynx and velopharynx, and the AP/LR ratio of the hypopharynx and velopharynx showed significant difference between the data from control and T2 group. The PE treatment of Class III malocclusion with maxillary skeletal hypoplasia leads to a significant increase in the volume of nasopharynx and velopharynx.

  8. Investigation of the effects of miniscrew-assisted rapid palatal expansion on airflow in the upper airway of an adult patient with obstructive sleep apnea syndrome using computational fluid-structure interaction analysis.

    Science.gov (United States)

    Hur, Jae-Sik; Kim, Hyoung-Ho; Choi, Jin-Young; Suh, Sang-Ho; Baek, Seung-Hak

    2017-11-01

    The objective of this study was to investigate the effects of miniscrew-assisted rapid palatal expansion (MARPE) on changes in airflow in the upper airway (UA) of an adult patient with obstructive sleep apnea syndrome (OSAS) using computational fluid-structure interaction analysis. Three-dimensional UA models fabricated from cone beam computed tomography images obtained before (T0) and after (T1) MARPE in an adult patient with OSAS were used for computational fluid dynamics with fluid-structure interaction analysis. Seven and nine cross-sectional planes (interplane distance of 10 mm) in the nasal cavity (NC) and pharynx, respectively, were set along UA. Changes in the cross-sectional area and changes in airflow velocity and pressure, node displacement, and total resistance at maximum inspiration (MI), rest, and maximum expiration (ME) were investigated at each plane after MARPE. The cross-sectional areas at most planes in NC and the upper half of the pharynx were significantly increased at T1. Moreover, airflow velocity decreased in the anterior NC at MI and ME and in the nasopharynx and oropharynx at MI. The decrease in velocity was greater in NC than in the pharynx. The airflow pressure in the anterior NC and entire pharynx exhibited a decrease at T1. The amount of node displacement in NC and the pharynx was insignificant at both T0 and T1. Absolute values for the total resistance at MI, rest, and ME were lower at T1 than at T0. MARPE improves airflow and decreases resistance in UA; therefore, it may be an effective treatment modality for adult patients with moderate OSAS.

  9. Avaliação cefalométrica das alterações verticais e anteroposteriores associadas ao uso do expansor maxilar com cobertura oclusal Cephalometric evaluation of vertical and anteroposterior changes associated with the use of bonded rapid maxillary expansion appliance

    Directory of Open Access Journals (Sweden)

    Moara De Rossi

    2010-06-01

    Full Text Available INTRODUÇÃO: os aparelhos expansores maxilares com cobertura oclusal têm sido sugeridos para controlar o aumento na dimensão vertical da face após a expansão rápida da maxila, porém ainda não há um consenso na literatura sobre seus reais efeitos. OBJETIVO: o objetivo deste trabalho foi avaliar as alterações cefalométricas verticais e anteroposteriores associadas à expansão da maxila realizada com o aparelho expansor com cobertura oclusal. MÉTODOS: a amostra foi composta por 25 crianças, de ambos os gêneros, com idades entre 6 e 10 anos, portadoras de mordida cruzada posterior esquelética. Após a expansão maxilar, o próprio aparelho expansor foi utilizado como contenção fixa. Foram analisadas telerradiografias em norma lateral tomadas antes do início do tratamento e após a remoção do aparelho expansor. CONCLUSÃO: com base nos resultados, pôde-se concluir que o uso do aparelho expansor com cobertura oclusal não alterou significativamente as medidas cefalométricas verticais e anteroposteriores das crianças.INTRODUCTION: Bonded rapid maxillary expansion appliances have been suggested to control increases in the vertical dimension of the face after rapid maxillary expansion but there is still no consensus in the literature concerning its actual effectiveness. OBJECTIVE: The purpose of this study was to evaluate the vertical and anteroposterior cephalometric changes associated with maxillary expansion performed using bonded rapid maxillary expansion appliances. METHODS: The sample consisted of 25 children of both genders, aged between 6 and 10 years old, with skeletal posterior crossbite. After maxillary expansion, the expansion appliance itself was used for fixed retention. Were analyzed lateral teleradiographs taken prior to treatment onset and after removal of the expansion appliance. CONCLUSION: Based on the results, it can be concluded that the use of bonded rapid maxillary expansion appliance did not significantly

  10. Rapid Response to Evaluate the Presence of Amphibian Chytrid Fungus (Batrachochytrium dendrobatidis) and Ranavirus in Wild Amphibian Populations in Madagascar.

    Science.gov (United States)

    Kolby, Jonathan E; Smith, Kristine M; Ramirez, Sara D; Rabemananjara, Falitiana; Pessier, Allan P; Brunner, Jesse L; Goldberg, Caren S; Berger, Lee; Skerratt, Lee F

    2015-01-01

    We performed a rapid response investigation to evaluate the presence and distribution of amphibian pathogens in Madagascar following our identification of amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd) and ranavirus in commercially exported amphibians. This targeted risk-based field surveillance program was conducted from February to April 2014 encompassing 12 regions and 47 survey sites. We simultaneously collected amphibian and environmental samples to increase survey sensitivity and performed sampling both in wilderness areas and commercial amphibian trade facilities. Bd was not detected in any of 508 amphibian skin swabs or 68 water filter samples, suggesting pathogen prevalence was below 0.8%, with 95% confidence during our visit. Ranavirus was detected in 5 of 97 amphibians, including one adult Mantidactylus cowanii and three unidentified larvae from Ranomafana National Park, and one adult Mantidactylus mocquardi from Ankaratra. Ranavirus was also detected in water samples collected from two commercial amphibian export facilities. We also provide the first report of an amphibian mass-mortality event observed in wild amphibians in Madagascar. Although neither Bd nor ranavirus appeared widespread in Madagascar during this investigation, additional health surveys are required to disentangle potential seasonal variations in pathogen abundance and detectability from actual changes in pathogen distribution and rates of spread. Accordingly, our results should be conservatively interpreted until a comparable survey effort during winter months has been performed. It is imperative that biosecurity practices be immediately adopted to limit the unintentional increased spread of disease through the movement of contaminated equipment or direct disposal of contaminated material from wildlife trade facilities. The presence of potentially introduced strains of ranaviruses suggests that Madagascar's reptile species might also be threatened by disease

  11. Rapid Response to Evaluate the Presence of Amphibian Chytrid Fungus (Batrachochytrium dendrobatidis) and Ranavirus in Wild Amphibian Populations in Madagascar

    Science.gov (United States)

    Kolby, Jonathan E.; Smith, Kristine M.; Ramirez, Sara D.; Rabemananjara, Falitiana; Pessier, Allan P.; Brunner, Jesse L.; Goldberg, Caren S.; Berger, Lee; Skerratt, Lee F.

    2015-01-01

    We performed a rapid response investigation to evaluate the presence and distribution of amphibian pathogens in Madagascar following our identification of amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd) and ranavirus in commercially exported amphibians. This targeted risk-based field surveillance program was conducted from February to April 2014 encompassing 12 regions and 47 survey sites. We simultaneously collected amphibian and environmental samples to increase survey sensitivity and performed sampling both in wilderness areas and commercial amphibian trade facilities. Bd was not detected in any of 508 amphibian skin swabs or 68 water filter samples, suggesting pathogen prevalence was below 0.8%, with 95% confidence during our visit. Ranavirus was detected in 5 of 97 amphibians, including one adult Mantidactylus cowanii and three unidentified larvae from Ranomafana National Park, and one adult Mantidactylus mocquardi from Ankaratra. Ranavirus was also detected in water samples collected from two commercial amphibian export facilities. We also provide the first report of an amphibian mass-mortality event observed in wild amphibians in Madagascar. Although neither Bd nor ranavirus appeared widespread in Madagascar during this investigation, additional health surveys are required to disentangle potential seasonal variations in pathogen abundance and detectability from actual changes in pathogen distribution and rates of spread. Accordingly, our results should be conservatively interpreted until a comparable survey effort during winter months has been performed. It is imperative that biosecurity practices be immediately adopted to limit the unintentional increased spread of disease through the movement of contaminated equipment or direct disposal of contaminated material from wildlife trade facilities. The presence of potentially introduced strains of ranaviruses suggests that Madagascar's reptile species might also be threatened by disease

  12. A expansão rápida da maxila com haas e a fala na fissura labiopalatina transforame Rapid maxillary expansion with Haas and the speech in people with cleft lip and palate

    Directory of Open Access Journals (Sweden)

    Christiane Moraes Lazzari

    2009-01-01

    Full Text Available OBJETIVO: verificar os efeitos da Expansão Rápida da Maxila (ERM, com aparelho Haas, na fala do paciente com fissura labiopalatina (FLP Transforame. MÉTODOS: 12 indivíduos entre sete e 14 anos, sendo seis meninos e seis meninas, divididos em dois grupos. O Grupo 1 (G1, submetido à ERM com protocolo de ativação convencional e, o Grupo 2 (G2, submetido à ERM com protocolo de ativação preconizado por Liou e Tsai (2005 com expansões e constrições alternadas. Realizou-se avaliação da fala, análise acústica com programa Praat e avaliação perceptivo-auditiva por julgadores fonoaudiólogos e leigos. RESULTADOS: a medição dos tempos de emissão das vogais por análise acústica mostrou diferença estatisticamente significante na avaliação pós-ERM da vogal /i/ no G1 e da vogal /a/ no G2. Na avaliação perceptivo-auditiva, não houve diferenças estatisticamente significantes entre os grupos nas avaliações de Nasalidade e Clareza na Articulação, porém, na medida em que os julgadores atribuíram melhora à Nasalidade, também atribuíram melhora à Articulação e, assim também em relação as variáveis "Melhor", "Igual" e "Pior". CONCLUSÃO: a diminuição dos tempos de emissão pós-ERM, indica que o aumento no escape aéreo nasal ocasiona menores tempos de emissão. A análise perceptivo-auditiva mostrou-se um instrumento eficaz de avaliação, havendo concordância entre julgadores leigos e fonoaudiólogos. Essa avaliação indicou também, que na medida em que a nasalidade diminui ocorre maior clareza na articulação.PURPOSE: to check the effects of rapid maxillary expansion (RME with Haas, made by orthodontistic, in speech of the patient with cleft lip and palate. METHODS: 12 subjects, 6 boys and 6 girls, with age between 7 and 14-year old, divided in two groups. Group 1 (G1, was submitted to conventional activation RME protocol and Group 2 (G2, was submitted to activation ERM protocol in accordance with Liou and Tsai

  13. On the Bantu expansion.

    Science.gov (United States)

    Rowold, Daine J; Perez-Benedico, David; Stojkovic, Oliver; Garcia-Bertrand, Ralph; Herrera, Rene J

    2016-11-15

    Here we report the results of fine resolution Y chromosomal analyses (Y-SNP and Y-STR) of 267 Bantu-speaking males from three populations located in the southeast region of Africa. In an effort to determine the relative Y chromosomal affinities of these three genotyped populations, the findings are interpreted in the context of 74 geographically and ethnically targeted African reference populations representing four major ethno-linguistic groups (Afro-Asiatic, Niger Kordofanin, Khoisan and Pygmoid). In this investigation, we detected a general similarity in the Y chromosome lineages among the geographically dispersed Bantu-speaking populations suggesting a shared heritage and the shallow time depth of the Bantu Expansion. Also, micro-variations in the Bantu Y chromosomal composition across the continent highlight location-specific gene flow patterns with non-Bantu-speaking populations (Khoisan, Pygmy, Afro-Asiatic). Our Y chromosomal results also indicate that the three Bantu-speaking Southeast populations genotyped exhibit unique gene flow patterns involving Eurasian populations but fail to reveal a prevailing genetic affinity to East or Central African Bantu-speaking groups. In addition, the Y-SNP data underscores a longitudinal partitioning in sub-Sahara Africa of two R1b1 subgroups, R1b1-P25* (west) and R1b1a2-M269 (east). No evidence was observed linking the B2a haplogroup detected in the genotyped Southeast African Bantu-speaking populations to gene flow from contemporary Khoisan groups. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Rapid Buildup of Genetic Diversity in Founder Populations of the Gynodioecious Plant Species Origanum vulgare after Semi-Natural Grassland Restoration

    Science.gov (United States)

    Helsen, Kenny; Jacquemyn, Hans; Hermy, Martin; Vandepitte, Katrien; Honnay, Olivier

    2013-01-01

    In most landscapes the success of habitat restoration is largely dependent on spontaneous colonization of plant species. This colonization process, and the outcome of restoration practices, can only be considered successful if the genetic makeup of founding populations is not eroded through founder effects and subsequent genetic drift. Here we used 10 microsatellite markers to investigate the genetic effects of recent colonization of the long-lived gynodioecious species Origanum vulgare in restored semi-natural grassland patches. We compared the genetic diversity and differentiation of fourteen recent populations with that of thirteen old, putative source populations, and we evaluated the effects of spatial configuration of the populations on colonization patterns. We did not observe decreased genetic diversity in recent populations, or inflated genetic differentiation among them. Nevertheless, a significantly higher inbreeding coefficient was observed in recent populations, although this was not associated with negative fitness effects. Overall population genetic differentiation was low (FST = 0.040). Individuals of restored populations were assigned to on average 6.1 different source populations (likely following the ‘migrant pool’ model). Gene flow was, however, affected by the spatial configuration of the grasslands, with gene flow into the recent populations mainly originating from nearby source populations. This study demonstrates how spontaneous colonization after habitat restoration can lead to viable populations in a relatively short time, overcoming pronounced founder effects, when several source populations are nearby. Restored populations can therefore rapidly act as stepping stones and sources of genetic diversity, likely increasing overall metapopulation viability of the study species. PMID:23840642

  15. Recent northward range expansion promotes song evolution in a passerine bird, the Light-vented Bulbul.

    Science.gov (United States)

    Xing, X Y; Alström, P; Yang, X J; Lei, F M

    2013-04-01

    In common with human speech, song is culturally inherited in oscine passerine birds ('songbirds'). Intraspecific divergence in birdsong, such as development of local dialects, might be an important early step in the speciation process. It is therefore vital to understand how songs diverge, especially in founding populations. The northward expansion of the Light-vented Bulbul Pycnonotus sinensis (J. F. Gmelin, 1789) into north China in the last 30 years provides an excellent opportunity to study birdsong evolution. We compared ~4400 songs from newly established northern populations with ~2900 songs from southern populations to evaluate song divergence after recent expansion. The total pool of syllables and especially song types was considerably smaller in the north than in the south, indicating 'founder effects' in the new population. The ancestral pattern of mosaic song dialects changed into a pattern of wide geographical sharing of a few song types and syllables, likely the result of fewer geographical barriers to 'meme flow', and the recent spread across a large area in the north. Our results suggest that song evolution and vocal trait shifts can arise rapidly after range expansion, and that in the Light-vented Bulbul 'founder effects', geographical isolation, and recent rapid expansions played important roles in the evolution of song dialects. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

  16. Spatial Linkage and Urban Expansion: AN Urban Agglomeration View

    Science.gov (United States)

    Jiao, L. M.; Tang, X.; Liu, X. P.

    2017-09-01

    Urban expansion displays different characteristics in each period. From the perspective of the urban agglomeration, studying the spatial and temporal characteristics of urban expansion plays an important role in understanding the complex relationship between urban expansion and network structure of urban agglomeration. We analyze urban expansion in the Yangtze River Delta Urban Agglomeration (YRD) through accessibility to and spatial interaction intensity from core cities as well as accessibility of road network. Results show that: (1) Correlation between urban expansion intensity and spatial indicators such as location and space syntax variables is remarkable and positive, while it decreases after rapid expansion. (2) Urban expansion velocity displays a positive correlation with spatial indicators mentioned above in the first (1980-1990) and second (1990-2000) period. However, it exhibits a negative relationship in the third period (2000-2010), i.e., cities located in the periphery of urban agglomeration developing more quickly. Consequently, the hypothesis of convergence of urban expansion in rapid expansion stage is put forward. (3) Results of Zipf's law and Gibrat's law show urban expansion in YRD displays a convergent trend in rapid expansion stage, small and medium-sized cities growing faster. This study shows that spatial linkage plays an important but evolving role in urban expansion within the urban agglomeration. In addition, it serves as a reference to the planning of Yangtze River Delta Urban Agglomeration and regulation of urban expansion of other urban agglomerations.

  17. SPATIAL LINKAGE AND URBAN EXPANSION: AN URBAN AGGLOMERATION VIEW

    Directory of Open Access Journals (Sweden)

    L. M. Jiao

    2017-09-01

    Full Text Available Urban expansion displays different characteristics in each period. From the perspective of the urban agglomeration, studying the spatial and temporal characteristics of urban expansion plays an important role in understanding the complex relationship between urban expansion and network structure of urban agglomeration. We analyze urban expansion in the Yangtze River Delta Urban Agglomeration (YRD through accessibility to and spatial interaction intensity from core cities as well as accessibility of road network. Results show that: (1 Correlation between urban expansion intensity and spatial indicators such as location and space syntax variables is remarkable and positive, while it decreases after rapid expansion. (2 Urban expansion velocity displays a positive correlation with spatial indicators mentioned above in the first (1980–1990 and second (1990–2000 period. However, it exhibits a negative relationship in the third period (2000–2010, i.e., cities located in the periphery of urban agglomeration developing more quickly. Consequently, the hypothesis of convergence of urban expansion in rapid expansion stage is put forward. (3 Results of Zipf’s law and Gibrat's law show urban expansion in YRD displays a convergent trend in rapid expansion stage, small and medium-sized cities growing faster. This study shows that spatial linkage plays an important but evolving role in urban expansion within the urban agglomeration. In addition, it serves as a reference to the planning of Yangtze River Delta Urban Agglomeration and regulation of urban expansion of other urban agglomerations.

  18. A Boom for Whom? Exploring the Impacts of a Rapid Increase in the Male Population Upon Women's Services in Darwin, Northern Territory.

    Science.gov (United States)

    Ennis, Gretchen; Tofa, Matalena; Finlayson, Mary; U'Ren, Julie

    2016-05-03

    A rapidly expanding natural-resource extraction industry and a growing military presence mean an increasingly male-skewed population for the city of Darwin, Australia. This has sparked concerns about the potential for increased violence against women. In this article, we present qualitative research detailing the views of 13 participants from 10 women's support services in the Darwin area. We argue that women's support services bear witness to and are tasked with responding to the impacts of population change on women, yet their work is undermined by uncertainties that stem from neoliberal funding rationales and limited demands on companies to address social issues. © The Author(s) 2016.

  19. Public health services and their relationship with rapid HIV test utilization and access for key populations in Morelos, Mexico

    Directory of Open Access Journals (Sweden)

    Carlos Jesús Conde González

    2015-07-01

    Full Text Available Objective. In 2009, 4 749 rapid HIV tests were run in Morelos, Mexico, despite lacking evidence on their results. This article seeks to analyze how public health organization relates to utility of rapid HIV test among healthcare users. Materials and methods. Joint study: comparison of differences in applied test and positive results for each group with the Bonferroni statistical tool, observational study in 34 health subsystems, and 11 interviews with public healthcare users. Results. Each subsystem processes influenced the use and usefulness of screening; for instance, primary care centers test only pregnant women and exclude men who have sex with men (MSM. That group shows significant differences (p<0.007 in the HIV-positive test with respect to other groups. Conclusions. Despite the availability of rapid detection tests and epidemiological evidence, the way public health services are organized impedes an efficient diagnosis in the group with higher risk, namely MSM. The distribution of rapid HIV tests was guided by stigmatization.

  20. Rapid assessment of genetic ancestry in populations of unknown origin by genome-wide genotyping of pooled samples.

    Directory of Open Access Journals (Sweden)

    Charleston W K Chiang

    2010-03-01

    Full Text Available As we move forward from the current generation of genome-wide association (GWA studies, additional cohorts of different ancestries will be studied to increase power, fine map association signals, and generalize association results to additional populations. Knowledge of genetic ancestry as well as population substructure will become increasingly important for GWA studies in populations of unknown ancestry. Here we propose genotyping pooled DNA samples using genome-wide SNP arrays as a viable option to efficiently and inexpensively estimate admixture proportion and identify ancestry informative markers (AIMs in populations of unknown origin. We constructed DNA pools from African American, Native Hawaiian, Latina, and Jamaican samples and genotyped them using the Affymetrix 6.0 array. Aided by individual genotype data from the African American cohort, we established quality control filters to remove poorly performing SNPs and estimated allele frequencies for the remaining SNPs in each panel. We then applied a regression-based method to estimate the proportion of admixture in each cohort using the allele frequencies estimated from pooling and populations from the International HapMap Consortium as reference panels, and identified AIMs unique to each population. In this study, we demonstrated that genotyping pooled DNA samples yields estimates of admixture proportion that are both consistent with our knowledge of population history and similar to those obtained by genotyping known AIMs. Furthermore, through validation by individual genotyping, we demonstrated that pooling is quite effective for identifying SNPs with large allele frequency differences (i.e., AIMs and that these AIMs are able to differentiate two closely related populations (HapMap JPT and CHB.

  1. Bridges Expansion Joints

    OpenAIRE

    Sergey W. Kozlachkow

    2012-01-01

    The survey is concerned with the expansion joints, used in bridge constructions to compensate medium and significant operational linear and spatial displacements between adjacent spans or between bridge span and pier. The analysis of design features of these types of expansion joints, their advantages and disadvantages, based on operational experience justified the necessity to design constructions, meeting the modern demands imposed to expansion joints.

  2. Managing the social impacts of the rapidly-expanding extractive industries in Greenland

    NARCIS (Netherlands)

    Hansen, Anne Merrild; Vanclay, Frank; Croal, Peter; Skjervedal, Anna Sofie Hurup

    2016-01-01

    The recent rapid expansion of extractive industries in Greenland is both causing high hopes for the future and anxieties among the local population. In the Arctic context, even small projects carry risks of major social impacts at local and national scales, and have the potential to severely affect

  3. Managing the social impacts of the rapidly expanding extractive industries in Greenland

    DEFF Research Database (Denmark)

    Hansen, Anne Merrild; Vanclay, Frank; Croal, Peter

    2016-01-01

    The recent rapid expansion of extractive industries in Greenland is both causing high hopes for the future and anxieties among the local population. In the Arctic context, even small projects carry risks of major social impacts at local and national scales, and have the potential to severely affect...

  4. Mitochondrial DNA Analyses Indicate High Diversity, Expansive Population Growth andHigh Genetic Connectivity of Vent Copepods (Dirivultidae) across Different Oceans

    NARCIS (Netherlands)

    Gollner, S.; Stuckas, H.; Kihara, T.C.; Kihara, S.; Kodami, S.; Martinez Arbizu, P.

    2016-01-01

    Communities in spatially fragmented deep-sea hydrothermal vents rich in polymetallic sulfides could soon face major disturbance events due to deep-sea mineral mining, such that unraveling patterns of gene flow between hydrothermal vent populations will be an important step in the development of

  5. Assessing service use for mental health by Indigenous populations in Australia, Canada, New Zealand and the United States of America: a rapid review of population surveys.

    Science.gov (United States)

    McIntyre, Cecily; Harris, Meredith G; Baxter, Amanda J; Leske, Stuart; Diminic, Sandra; Gone, Joseph P; Hunter, Ernest; Whiteford, Harvey

    2017-08-04

    Indigenous people in Australia, Canada, New Zealand and the United States of America experience disproportionately poor mental health compared to their non-Indigenous counterparts. To optimally allocate resources, health planners require information about the services Indigenous people use for mental health, their unmet treatment needs and the barriers to care. We reviewed population surveys of Indigenous people to determine whether the information needed to guide service development is being collected. We sought national- or state-level epidemiological surveys of Indigenous populations conducted in each of the four selected countries since 1990 that asked about service use for mental health. Surveys were identified from literature reviews and web searches. We developed a framework for categorising the content of each survey. Using this framework, we compared the service use content of the surveys of Indigenous people to each other and to general population mental health surveys. We focused on identifying gaps in information coverage and topics that may require Indigenous-specific questions or response options. Nine surveys met our inclusion criteria. More than half of these included questions about health professionals consulted, barriers to care, perceived need for care, medications taken, number, duration, location and payment of health professional visits or use of support services or self-management. Less than half included questions about interventions received, hospital admissions or treatment dropout. Indigenous-specific content was most common in questions regarding use of support services or self-management, types of health professionals consulted, barriers to care and interventions received. Epidemiological surveys measuring service use for mental health among Indigenous populations have been less comprehensive and less standardised than surveys of the general population, despite having assessed similar content. To better understand the gaps in mental

  6. On skin expansion.

    Science.gov (United States)

    Pamplona, Djenane C; Velloso, Raquel Q; Radwanski, Henrique N

    2014-01-01

    This article discusses skin expansion without considering cellular growth of the skin. An in vivo analysis was carried out that involved expansion at three different sites on one patient, allowing for the observation of the relaxation process. Those measurements were used to characterize the human skin of the thorax during the surgical process of skin expansion. A comparison between the in vivo results and the numerical finite elements model of the expansion was used to identify the material elastic parameters of the skin of the thorax of that patient. Delfino's constitutive equation was chosen to model the in vivo results. The skin is considered to be an isotropic, homogeneous, hyperelastic, and incompressible membrane. When the skin is extended, such as with expanders, the collagen fibers are also extended and cause stiffening in the skin, which results in increasing resistance to expansion or further stretching. We observed this phenomenon as an increase in the parameters as subsequent expansions continued. The number and shape of the skin expanders used in expansions were also studied, both mathematically and experimentally. The choice of the site where the expansion should be performed is discussed to enlighten problems that can lead to frustrated skin expansions. These results are very encouraging and provide insight into our understanding of the behavior of stretched skin by expansion. To our knowledge, this study has provided results that considerably improve our understanding of the behavior of human skin under expansion. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Carboxylesterase 1A2 encoding gene with increased transcription and potential rapid drug metabolism in Asian populations

    DEFF Research Database (Denmark)

    Rasmussen, Henrik Berg; Madsen, Majbritt Busk; Lyauk, Yassine Kamal

    2017-01-01

    The carboxylesterase 1 gene (CES1) encodes a hydrolase implicated in the metabolism of commonly used drugs. CES1A2, a hybrid of CES1 and a CES1-like pseudogene, has a promoter that is weak in most individuals. However, some individuals harbor a promoter haplotype of this gene with two overlapping...... Sp1 sites that confer significantly increased transcription potentially leading to rapid drug metabolism. This CES1A2 haplotype has previously been reported to be common among Asians. Using polymerase chain reaction followed by sequencing, the present study examined variation in the promoter and 5...

  8. Comparative phylogeography of Atlantic bluefin tuna and swordfish: the combined effects of vicariance, secondary contact, introgression, and population expansion on the regional phylogenies of two highly migratory pelagic fishes.

    Science.gov (United States)

    Alvarado Bremer, Jaime R; Viñas, Jordi; Mejuto, Jaime; Ely, Bert; Pla, Carles

    2005-07-01

    Comparative phylogeography has revealed remarkable patterns of concordance in the maternal phylogenies of many species. The phylogeography and historical demography of the mitochondrial control region I for 607 Atlantic bluefin tuna (Thunnus thynnus) and 275 swordfish (Xiphias gladius) were analyzed to clarify the complex phylogenetic signals in the North Atlantic-Mediterranean region where they are sympatric. Atlantic bluefin tuna mtDNA is polyphyletic, and includes rare sequences sister to Pacific bluefin tuna (Thunnus orientalis) and introgressed albacore (Thunnus alalunga) sequences. There is no geographic partitioning between Atlantic and Mediterranean samples of Atlantic bluefin tuna (Phi(ST)=0.002). In contrast, Atlantic and Mediterranean swordfish are differentiated (Phi(ST)=0.091) due to the combined effects of vicariance, secondary contact, and dissimilar regional demographic histories. Mediterranean swordfish has substantially less variation, and a more recent history (tau=2.42) than that of Atlantic swordfish (tau=7.02). In spite of the discordant phylogenetic and phylogeographic signals, the demographic history of Atlantic swordfish and Atlantic bluefin tuna (tau=7.51) suggests concordance in the timeline of population expansion. Possible scenarios of cladogenesis, expansion, and contraction, influenced by glacial cycles during the Pleistocene, are formulated.

  9. Rapidly increasing body mass index among children, adolescents and young adults in a transitioning population, South Africa, 2008-15

    DEFF Research Database (Denmark)

    Sartorius, B; Sartorius, K; Taylor, M

    2017-01-01

    budget. Our refined understanding highlights that risks are further compounded for certain groups/places, and emphasizes that urgent geographical and population-targeted interventions are necessary. These interventions could include a sugar tax, clearer food labelling, revised school feeding programmes...

  10. Rapid increase in log populations in drought-stressed mixed-conifer and ponderosa pine forests in northern Arizona

    Science.gov (United States)

    Joseph L. Ganey; Scott C. Vojta

    2012-01-01

    Down logs provide important ecosystem services in forests and affect surface fuel loads and fire behavior. Amounts and kinds of logs are influenced by factors such as forest type, disturbance regime, forest man-agement, and climate. To quantify potential short-term changes in log populations during a recent global- climate-change type drought, we sampled logs in mixed-...

  11. Development of a rapid multiplex SSR genotyping method to study populations of the fun-gal plant pathogen Zymoseptoria tritici

    NARCIS (Netherlands)

    Gautier, A.; Marcel, T.C.; Confais, J.; Crane, C.; Kema, G.H.J.; Suffert, F.; Walker, A.S.

    2014-01-01

    Background Zymoseptoria tritici is a hemibiotrophic ascomycete fungus causing leaf blotch of wheat that often decreases yield severely. Populations of the fungus are known to be highly diverse and poorly differentiated from each other. However, a genotyping tool is needed to address further

  12. Development of a rapid multiplex SSR genotyping method to study populations of the fungal plant pathogen Zymoseptoria tritici.

    Science.gov (United States)

    Gautier, Angélique; Marcel, Thierry C; Confais, Johann; Crane, Charles; Kema, Gert; Suffert, Frédéric; Walker, Anne-Sophie

    2014-06-18

    Zymoseptoria tritici is a hemibiotrophic ascomycete fungus causing leaf blotch of wheat that often decreases yield severely. Populations of the fungus are known to be highly diverse and poorly differentiated from each other. However, a genotyping tool is needed to address further questions in large collections of isolates, regarding regional population structure, adaptation to anthropogenic selective pressures, and dynamics of the recently discovered accessory chromosomes. This procedure is limited by costly and time-consuming simplex PCR genotyping. Recent development of genomic approaches and of larger sets of SSRs enabled the optimization of microsatellite multiplexing. We report here a reliable protocol to amplify 24 SSRs organized in three multiplex panels, and covering all Z. tritici chromosomes. We also propose an automatic allele assignment procedure, which allows scoring alleles in a repeatable manner across studies and laboratories. All together, these tools enabled us to characterize local and worldwide populations and to calculate diversity indexes consistent with results reported in the literature. This easy-to-use, accurate, repeatable, economical, and faster technical strategy can provide useful genetic information for evolutionary inferences concerning Z. tritici populations. Moreover, it will facilitate the comparison of studies from different scientific groups.

  13. Previsibilidade de sucesso na disjunção palatina avaliada pelo estágio de maturação esquelética: estudo piloto Sucess predictability in rapid maxillary expansion when assessed by skeletal growth maturation phase: pilot study

    Directory of Open Access Journals (Sweden)

    Rodrigo Rezende de Albuquerque

    2006-04-01

    Full Text Available OBJETIVO: a proposta deste estudo foi determinar se a previsibilidade de sucesso da disjunção palatina está correlacionada a algum evento de maturidade esquelética que determine o final do crescimento geral do organismo. METODOLOGIA: utilizando o conhecimento dos estágios de maturação esquelética visualizados por radiografia de mão e punho e registrados em um gráfico do surto de crescimento puberal, foram avaliados dezenove pacientes de ambos os gêneros, com idades variando de dez anos e três meses a vinte e oito anos e quatro meses, supervisionados por análises clínicas e radiográficas específicas antes e após o procedimento de disjunção palatina. RESULTADO E CONCLUSÃO: pode-se afirmar que não foi possível determinar a previsibilidade de sucesso da disjunção palatina quando esta foi correlacionada com a ossificação total do osso rádio.AIM: to evaluate the possibility of rapid maxillary expansion in patients who have reached the decisive event of facial growth ending (total fusion of the radius. METHODS: the study was held using esqueletal maturation data from hand and wrist x-ray plotted in a puberal growth spurt graph from nineteen patients of both genders at ages ranging from ten years and three months to twenty-eight years and four months surveilled by specific clinical and radiographic analysis before and after the rapid maxillary expansion procedure. RESULTS AND CONCLUSION: it could be concluded that it was not possible to establish a successful correlation between total fusion of radius with rapid maxillary expansion.

  14. Post-Glacial Expansion and Population Genetic Divergence of Mangrove Species Avicennia germinans (L.) Stearn and Rhizophora mangle L. along the Mexican Coast

    Science.gov (United States)

    Sandoval-Castro, Eduardo; Dodd, Richard S.; Riosmena-Rodríguez, Rafael; Enríquez-Paredes, Luis Manuel; Tovilla-Hernández, Cristian; López-Vivas, Juan Manuel; Aguilar-May, Bily; Muñiz-Salazar, Raquel

    2014-01-01

    Mangrove forests in the Gulf of California, Mexico represent the northernmost populations along the Pacific coast and thus they are likely to be source populations for colonization at higher latitudes as climate becomes more favorable. Today, these populations are relatively small and fragmented and prior research has indicated that they are poor in genetic diversity. Here we set out to investigate whether the low diversity in this region was a result of recent colonization, or fragmentation and genetic drift of once more extensive mangroves due to climatic changes in the recent past. By sampling the two major mangrove species, Rhizophora mangle and Avicennia germinans, along the Pacific and Atlantic coasts of Mexico, we set out to test whether concordant genetic signals could elucidate recent evolution of the ecosystem. Genetic diversity of both mangrove species showed a decreasing trend toward northern latitudes along the Pacific coast. The lowest levels of genetic diversity were found at the range limits around the Gulf of California and the outer Baja California peninsula. Lack of a strong spatial genetic structure in this area and recent northern gene flow in A. germinans suggest recent colonization by this species. On the other hand, lack of a signal of recent northern dispersal in R. mangle, despite the higher dispersal capability of this species, indicates a longer presence of populations, at least in the southern Gulf of California. We suggest that the longer history, together with higher genetic diversity of R. mangle at the range limits, likely provides a gene pool better able to colonize northwards under climate change than A. germinans. PMID:24699389

  15. Post-glacial expansion and population genetic divergence of mangrove species Avicennia germinans (L.) Stearn and Rhizophora mangle L. along the Mexican coast.

    Science.gov (United States)

    Sandoval-Castro, Eduardo; Dodd, Richard S; Riosmena-Rodríguez, Rafael; Enríquez-Paredes, Luis Manuel; Tovilla-Hernández, Cristian; López-Vivas, Juan Manuel; Aguilar-May, Bily; Muñiz-Salazar, Raquel

    2014-01-01

    Mangrove forests in the Gulf of California, Mexico represent the northernmost populations along the Pacific coast and thus they are likely to be source populations for colonization at higher latitudes as climate becomes more favorable. Today, these populations are relatively small and fragmented and prior research has indicated that they are poor in genetic diversity. Here we set out to investigate whether the low diversity in this region was a result of recent colonization, or fragmentation and genetic drift of once more extensive mangroves due to climatic changes in the recent past. By sampling the two major mangrove species, Rhizophora mangle and Avicennia germinans, along the Pacific and Atlantic coasts of Mexico, we set out to test whether concordant genetic signals could elucidate recent evolution of the ecosystem. Genetic diversity of both mangrove species showed a decreasing trend toward northern latitudes along the Pacific coast. The lowest levels of genetic diversity were found at the range limits around the Gulf of California and the outer Baja California peninsula. Lack of a strong spatial genetic structure in this area and recent northern gene flow in A. germinans suggest recent colonization by this species. On the other hand, lack of a signal of recent northern dispersal in R. mangle, despite the higher dispersal capability of this species, indicates a longer presence of populations, at least in the southern Gulf of California. We suggest that the longer history, together with higher genetic diversity of R. mangle at the range limits, likely provides a gene pool better able to colonize northwards under climate change than A. germinans.

  16. Lack of global population genetic differentiation in thearbuscular mycorrhizal fungus Glomus mosseae suggestsa recent range expansion which may have coincided withthe spread of agriculture

    DEFF Research Database (Denmark)

    Rosendahl, Søren; McGee, Peter; Morton, Joseph B

    2009-01-01

    The arbuscular mycorrhizal fungus Glomus mosseae is commonly found in agricultural fields. The cosmopolitan species is found in Africa, Europe, America, Asia and Australia. Three hypotheses may explain this worldwide distribution: First, speciation occurred before the continents separated 120 Ma;...... happened much later than continental spread and that human activity may have had a major impact on the dispersal and the population structure of the fungus....

  17. Deferred pre-emptive switch from calcineurin inhibitor to sirolimus leads to improvement in GFR and expansion of T regulatory cell population: a randomized, controlled trial.

    Directory of Open Access Journals (Sweden)

    Dinesh Bansal

    Full Text Available Measures to prevent chronic calcineurin inhibitor (CNI toxicity have included limiting exposure by switching to sirolimus (SIR. SIR may favorably influence T regulator cell (T(reg population. This randomized controlled trial compares the effect of switching from CNI to SIR on glomerular filtration rate (GFR and T(reg frequency.In this prospective open label randomized trial, primary living donor kidney transplant recipients on CNI-based immunosuppression were randomized to continue CNI or switched to sirolimus 2 months after surgery; 29 were randomized to receive CNI and 31 to SIR. All patients received mycophenolate mofetil and steroids. The main outcome parameter was estimated GFR (eGFR at 180 days. T(reg population was estimated by flowcytometry.Baseline characteristics in the two groups were similar. Forty-eight patients completed the trial. At six months, patients in the SIR group had significantly higher eGFR as compared to those in the CNI group (88.94 ± 11.78 vs 80.59 ± 16.51 mL/min, p = 0.038. Patients on SIR had a 12 mL/min gain of eGFR of at the end of six months. Patients in the SIR group showed significant increase in T(reg population at 30 days, which persisted till day 180. There was no difference in the adverse events in terms of number of acute rejection episodes, death, infections, proteinuria, lipid profile, blood pressure control and hematological parameters between the two groups. Four patients taking SIR developed enthesitis. No patient left the study or switched treatment because of adverse event.A deferred pre-emptive switch over from CNI to SIR safely improves renal function and T(reg population at 6 months in living donor kidney transplant recipients. Registered in Clinical Trials Registry of India (CTRI/2011/091/000034.

  18. Rapid changes in key ruminal microbial populations during the induction of and recovery from diet-induced milk fat depression in dairy cows.

    Science.gov (United States)

    Rico, D E; Preston, S H; Risser, J M; Harvatine, K J

    2015-08-14

    The ruminant provides a powerful model for understanding the temporal dynamics of gastrointestinal microbial communities. Diet-induced milk fat depression (MFD) in the dairy cow is caused by rumen-derived bioactive fatty acids, and is commonly attributed to the changes in the microbial population. The aim of the present study was to determine the changes occurring in nine ruminal bacterial taxa with well-characterised functions, and abundance of total fungi, ciliate protozoa and bacteria during the induction of and recovery from MFD. Interactions between treatment and time were observed for ten of the twelve populations. The total number of both fungi and ciliate protozoa decreased rapidly (days 4 and 8, respectively) by more than 90% during the induction period and increased during the recovery period. The abundance of Streptococcus bovis (amylolytic) peaked at 350% of control levels on day 4 of induction and rapidly decreased during the recovery period. The abundance of Prevotella bryantii (amylolytic) decreased by 66% from day 8 to 20 of the induction period and increased to the control levels on day 12 of the recovery period. The abundance of Megasphaera elsdenii and Selenomonas ruminantium (lactate-utilising bacteria) increased progressively until day 12 of induction (>170%) and decreased during the recovery period. The abundance of Fibrobacter succinogenes (fibrolytic) decreased by 97% on day 4 of induction and increased progressively to an equal extent during the recovery period, although smaller changes were observed for other fibrolytic bacteria. The abundance of the Butyrivibrio fibrisolvens/Pseudobutyrivibrio group decreased progressively during the induction period and increased during the recovery period, whereas the abundance of Butyrivibrio hungatei was not affected by treatment. Responsive taxa were modified rapidly, with the majority of changes occurring within 8 d and their time course was similar to the time course of the induction of MFD

  19. Populism

    OpenAIRE

    Abts, Koenraad; Van Kessel, Stijn

    2015-01-01

    Populism is a concept applied to a wide range of political movements and actors across the globe. There is, at the same time, considerable confusion about the attributes and manifestation of populism, as well as its impact on democracy. This contribution identifies the defining elements of the populist ideology and discusses the varieties in which populism manifests itself, for instance as a component of certain party families. We finally discuss various normative interpretations of populism,...

  20. Correlation between transverse expansion and increase in the upper arch perimeter after rapid maxillary expansion Correlação entre expansão transversal e aumento no perímetro do arco dentário após disjunção maxilar

    Directory of Open Access Journals (Sweden)

    Cristiane Aparecida de Assis Claro

    2006-03-01

    Full Text Available The purpose of the present study was to assess the correlation between transverse expansion and the increase in upper arch perimeter, after maxillary expansion. Dental casts of eighteen patients were obtained before treatment and again five months after maxillary expansion. Measurements of intermolar width, intercanine width, arch length and arch perimeter were made with a digital caliper on photocopies taken from the dental casts. After assessment of the method error, a multiple regression model was developed following the identification of the best subset of variables. The resulting equation led to the conclusion that the increase in arch perimeter is approximately given by the addition of 0.54 times the intercanine expansion, and 0.87 times the arch length alteration.O presente estudo avaliou a correlação entre expansão transversal e aumento no perímetro do arco dentário superior, após disjunção maxilar, em dezoito pares de modelos de gesso, obtidos antes e depois de aproximadamente cinco meses da disjunção maxilar. Os modelos foram fotocopiados e as variáveis largura intermolares, largura intercaninos, comprimento e perímetro do arco dentário superior foram mensuradas por meio de paquímetro digital. Depois de verificado o erro do método, um modelo de regressão múltipla foi desenvolvido em seqüência à identificação do melhor conjunto de variáveis. A equação resultante permitiu concluir que o aumento no perímetro do arco é dado pela adição de 0,54 vezes a alteração intercaninos e de 0,87 vezes a alteração no comprimento do arco.

  1. A Recent Expansion of the RXLR Effector Gene Avrblb2 Is Maintained in Global Populations of Phytophthora infestans Indicating Different Contributions to Virulence.

    Science.gov (United States)

    Oliva, Ricardo F; Cano, Liliana M; Raffaele, Sylvain; Win, Joe; Bozkurt, Tolga O; Belhaj, Khaoula; Oh, Sang-Keun; Thines, Marco; Kamoun, Sophien

    2015-08-01

    The introgression of disease resistance (R) genes encoding immunoreceptors with broad-spectrum recognition into cultivated potato appears to be the most promising approach to achieve sustainable management of late blight caused by the oomycete pathogen Phytophthora infestans. Rpi-blb2 from Solanum bulbocastanum shows great potential for use in agriculture based on preliminary potato disease trials. Rpi-blb2 confers immunity by recognizing the P. infestans avirulence effector protein AVRblb2 after it is translocated inside the plant cell. This effector belongs to the RXLR class of effectors and is under strong positive selection. Structure-function analyses revealed a key polymorphic amino acid (position 69) in AVRblb2 effector that is critical for activation of Rpi-blb2. In this study, we reconstructed the evolutionary history of the Avrblb2 gene family and further characterized its genetic structure in worldwide populations. Our data indicate that Avrblb2 evolved as a single-copy gene in a putative ancestral species of P. infestans and has recently expanded in the Phytophthora spp. that infect solanaceous hosts. As a consequence, at least four variants of AVRblb2 arose in P. infestans. One of these variants, with a Phe residue at position 69, evades recognition by the cognate resistance gene. Surprisingly, all Avrblb2 variants are maintained in pathogen populations. This suggests a potential benefit for the pathogen in preserving duplicated versions of AVRblb2, possibly because the variants may have different contributions to pathogen fitness in a diversified solanaceous host environment.

  2. Rapid differentiation of Listeria monocytogenes epidemic clones III and IV and their intact compared with heat-killed populations using Fourier transform infrared spectroscopy and chemometrics.

    Science.gov (United States)

    Nyarko, Esmond B; Puzey, Kenneth A; Donnelly, Catherine W

    2014-06-01

    The objectives of this study were to determine if Fourier transform infrared (FT-IR) spectroscopy and multivariate statistical analysis (chemometrics) could be used to rapidly differentiate epidemic clones (ECs) of Listeria monocytogenes, as well as their intact compared with heat-killed populations. FT-IR spectra were collected from dried thin smears on infrared slides prepared from aliquots of 10 μL of each L. monocytogenes ECs (ECIII: J1-101 and R2-499; ECIV: J1-129 and J1-220), and also from intact and heat-killed cell populations of each EC strain using 250 scans at a resolution of 4 cm(-1) in the mid-infrared region in a reflectance mode. Chemometric analysis of spectra involved the application of the multivariate discriminant method for canonical variate analysis (CVA) and linear discriminant analysis (LDA). CVA of the spectra in the wavelength region 4000 to 600 cm(-1) separated the EC strains while LDA resulted in a 100% accurate classification of all spectra in the data set. Further, CVA separated intact and heat-killed cells of each EC strain and there was 100% accuracy in the classification of all spectra when LDA was applied. FT-IR spectral wavenumbers 1650 to 1390 cm(-1) were used to separate heat-killed and intact populations of L. monocytogenes. The FT-IR spectroscopy method allowed discrimination between strains that belong to the same EC. FT-IR is a highly discriminatory and reproducible method that can be used for the rapid subtyping of L. monocytogenes, as well as for the detection of live compared with dead populations of the organism. Fourier transform infrared (FT-IR) spectroscopy and multivariate statistical analysis can be used for L. monocytogenes source tracking and for clinical case isolate comparison during epidemiological investigations since the method is capable of differentiating epidemic clones and it uses a library of well-characterized strains. The FT-IR method is potentially less expensive and more rapid compared to genetic

  3. A rapid and sensitive GC-MS/MS method to measure deuterium labeled deoxyadenosine in DNA from limited mouse cell populations

    Science.gov (United States)

    Farthing, Don E.; Buxbaum, Nataliya P.; Bare, Catherine V.; Treadwell, Shirin M.; Kapoor, Veena; Williams, Kirsten M.; Gress, Ronald E.

    2013-01-01

    A rapid and sensitive GC-MS/MS method was developed to quantitatively measure low levels of DNA base deoxyadenosine (dA) and its isotopologues (e.g. dA M+1) from limited mouse cell populations. Mice undergoing allogeneic hematopoietic transplantation (AHSCT) received deuterated water at biologically relevant time intervals post AHSCT, allowing labeling of DNA upon cell division, which was detected as the dA M+1 isotopologue. Targeted mouse cell populations were isolated from lymphoid organs and purified by multi-parameter fluorescence activated cell sorting. Cell lysis, DNA extraction and hydrolysis were accomplished using available commercial procedures. The novel analytical method utilized a hydrophilic-lipophilic balanced sample preparation, rapid on-line hot GC inlet gas phase sample derivatization, fast GC low thermal mass technology, and a recently marketed GC-MS/MS system. Calibration standards containing dA and fortified with relevant levels of dA M+1 (0.25–20%) and dA M+5 (internal standard) were used for sample quantitation. The method employed a quadratic fit for calibration of dA M+1 (0.25–20%) and dA, demonstrated excellent accuracy and precision, and had limits of detection of 100 fg on-column for the dA isotopologues. The method was validated and required only 20,000 cells to characterize population dynamics of cells involved in the biology of chronic graft-versus-host disease, the main cause of late morbidity and non-relapse-mortality following AHSCT. The high sensitivity and specificity of the method makes it useful for investigating in vivo kinetics on limited and important cell populations (e.g. T regulatory cells) from disease conditions or in disease models that are immune-mediated, such as diabetes, HIV/AIDS, arthritis, inflammatory bowel disease, and multiple sclerosis. PMID:23541182

  4. Bridges Expansion Joints

    Directory of Open Access Journals (Sweden)

    Sergey W. Kozlachkow

    2012-05-01

    Full Text Available The survey is concerned with the expansion joints, used in bridge constructions to compensate medium and significant operational linear and spatial displacements between adjacent spans or between bridge span and pier. The analysis of design features of these types of expansion joints, their advantages and disadvantages, based on operational experience justified the necessity to design constructions, meeting the modern demands imposed to expansion joints.

  5. High incidence of community-acquired pneumonia among rapidly aging population in Japan: a prospective hospital-based surveillance.

    Science.gov (United States)

    Takaki, Masahiro; Nakama, Takahiro; Ishida, Masayuki; Morimoto, Hitomi; Nagasaki, Yuka; Shiramizu, Rina; Hamashige, Naohisa; Chikamori, Masayuki; Yoshida, Laymyint; Ariyoshi, Koya; Suzuki, Motoi; Morimoto, Konosuke

    2014-01-01

    The age-group-specific incidence and etiological patterns of community-acquired pneumonia (CAP) have not been fully established in Japan. A 2-year prospective surveillance was conducted in Kochi city, Western Japan. All CAP patients aged ≥15 years who visited a community-based hospital were enrolled in the study. Clinical samples were examined by conventional bacterial culture and urinary antigen tests, and 6 bacterial pathogens and 16 respiratory viruses were identified from sputum samples by multiplex polymerase chain reaction assays. The age-group-specific incidence of CAP was estimated using a population-based data set of the total number of outpatients in the whole city. Ninety of the 131 enrolled patients, 68.7% were positive for respiratory pathogens. Streptococcus pneumoniae was the leading bacterial pathogen identified (28.2%). Respiratory viruses were identified in 36 patients (27.5%), and human entero-rhinovirus was the most common (13.3%) among them. The estimated overall incidence of adult CAP in Kochi was 9.6 per 1,000 person-years (PY); the estimated age group-specific incidence was 3.4, 10.7, and 42.9 per 1,000 PY for those aged 15-64, 65-74, and ≥75 years, respectively. The high incidence of CAP in these rural city of Japan, probably reflects the substantial aged population. S. pneumoniae and respiratory viruses play important roles in CAP in all age groups.

  6. Bridges Expansion Joints

    National Research Council Canada - National Science Library

    Sergey W. Kozlachkow

    2012-01-01

    .... The analysis of design features of these types of expansion joints, their advantages and disadvantages, based on operational experience justified the necessity to design constructions, meeting...

  7. Measurement of proliferation and disappearance of rapid turnover cell populations in human studies using deuterium-labeled glucose.

    Science.gov (United States)

    Macallan, Derek C; Asquith, Becca; Zhang, Yan; de Lara, Catherine; Ghattas, Hala; Defoiche, Julien; Beverley, Peter C L

    2009-01-01

    Cell proliferation may be measured in vivo by quantifying DNA synthesis with isotopically labeled deoxyribonucleotide precursors. Deuterium-labeled glucose is one such precursor which, because it achieves high levels of enrichment for a short period, is well suited to the study of rapidly dividing cells, in contrast to the longer term labeling achieved with heavy water ((2)H(2)O). As deuterium is non-radioactive and glucose can be readily administered, this approach is suitable for clinical studies. It has been widely applied to investigate human lymphocyte proliferation, but solid tissue samples may also be analyzed. Rate, duration and route (intravenous or oral) of [6,6-(2)H(2)]-glucose administration should be adapted to the target cell of interest. For lymphocytes, cell separation is best achieved by fluorescence activated cell sorting (FACS), although magnetic bead separation is an alternative. DNA is then extracted, hydrolyzed enzymatically and analyzed by gas chromatography mass spectrometry (GC/MS). Appropriate mathematical modeling is critical to interpretation. Typical time requirements are as follows: labeling, 10-24 h; sampling, approximately 3 weeks; DNA extraction/derivatization, 2-3 d; and GC/MS analysis, approximately 2 d.

  8. Rapid impact of rotavirus vaccine introduction to the National Immunization plan in southern Israel: comparison between 2 distinct populations.

    Science.gov (United States)

    Givon-Lavi, Noga; Ben-Shimol, Shalom; Cohen, Raanan; Greenberg, David; Dagan, Ron

    2015-04-15

    Rotavirus vaccines were licensed in Israel in 2007, and in 2011 the pentavalent-vaccine (RV5) was introduced into the Israeli National Immunization plan. To determine the effect of rotavirus-vaccines on the incidence of hospital visits due to rotavirus gastroenteritis (RVGE) and all-cause diarrhea in Jewish and Bedouin children vaccine period, the overall RVGE hospital visits rates per 1000 in children Vaccine uptake was faster in the Jewish vs. the Bedouin population. In the year following RV5 introduction, RVGE hospital visits rates declined by 82%, 70% (Pvaccine introduction in southern Israel in both Jewish and Bedouin children. However, the impact was faster and more profound in Jewish children, probably related to higher vaccine uptake and possibly to lifestyle differences. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Avaliação do efeito da expansão rápida da maxila na via aérea superior, por meio da nasofibroscopia: descrição da técnica e relato de caso Evaluation of the effect of rapid maxillary expansion on the upper airway using nasofibroscopy: case report and description of the technique

    Directory of Open Access Journals (Sweden)

    Edmilsson Pedro Jorge

    2011-02-01

    Full Text Available A finalidade deste artigo é avaliar o efeito da expansão rápida da maxila (ERM na via aérea superior. Por intermédio de um caso clínico, será relatado como indivíduos com atresia da maxila e com comprometimento da função naso-respiratória podem beneficiar-se com a ERM. Para entender melhor as alterações morfológicas decorrentes do paciente com problemas respiratórios, deve-se conhecer a anatomia e a fisiologia do sistema respiratório. Entretanto, não se pode esquecer que o tratamento deste paciente é multidisciplinar, envolvendo o ortodontista, otorrinolaringologista e a fonoaudióloga.The aim of the present investigation is to evaluate the effect of rapid maxillary expansion (RME on the upper airway. A clinical case is presented to describe how patients with atresic maxilla and reduced naso-respiratory function can have benefits from rapid maxillary expansion. In order to better understand the morphological alterations present in patients with respiratory disorders, it is necessary to understand the respiratory system's anatomy and physiology. However, it is relevant to mention that this patient undergoes a multidisciplinary treatment, involving the orthodontist, the otorhinolaryngologist and the phonoaudiologist.

  10. A survey of a population of anaesthesiologists from South India regarding practices for rapid sequence intubation in patients with head injury

    Directory of Open Access Journals (Sweden)

    Satyen Parida

    2016-01-01

    Full Text Available Background and Aims: Evidence and utility of the individual steps of the rapid sequence induction and tracheal intubation protocols have been debated, especially in the setting of traumatic brain injury. The purpose of this survey was to determine preferences in the current approach to rapid sequence intubation ( RSI in head injury patients among a population of anaesthesiologists from South India. Methods: A questionnaire was E-mailed to all the members of the Indian Society of Anaesthesiologists′ South Zone Chapter to ascertain their preferences, experience and comfort level with regard to their use of rapid sequence intubation techniques in adult patients with head injury. Participants were requested to indicate their practices for RSI technique for a head-injured patient upon arrival at the Emergency Medical Services department of their hospital. Results: The total response rate was 56.9% (530/932. Of the total respondents, 35% of the clinicians used cricoid pressure routinely, most respondents (68% stated that they pre-oxygenate the patients for about 3 min prior to RSI, thiopentone (61% and propofol (34% were commonly used prior to intubation. Rocuronium was the muscle relaxant of choice for RSI among the majority (44%, compared to succinylcholine (39%. Statistical analyses were performed after the initial entry onto a spreadsheet. Data were summarised descriptively using frequency distribution. Conclusion: In a rapid sequence intubation situation, the practice differed significantly among anaesthesiologists. Owing to disagreements and paucity of evidence-based data regarding the standards of RSI, it is apparent that RSI practice still has considerable variability in clinical practice.

  11. Design and manufacturing of customised femoral stems for the Indian population using rapid manufacturing: a finite element approach.

    Science.gov (United States)

    Madhugiri, T S; Kuthe, A M; Deshmukh, T R

    2011-01-01

    Joint replacement surgeries in India primarily involve the use of conventional implants, also referred to as 'standard implants'. There has been a little awareness about the possibility of using customised implants for such surgeries. Although standard implants from various biomedical companies are easily available in the Indian market, they are expensive and rarely conform to patient's anatomy. Studies in the past have shown that there are anatomical variations in the hip joint for different ethnic backgrounds and geographical locations. This article evaluates the feasibility of using custom-manufactured hip implants and presents a comparison between the former and standard implant from stress reduction point of view. Two CAD models of femoral stems - one from standard sized hip implant available in the market and other from customised hip implant designed as per parameters from a radiograph (specific to the patient's anatomy) - are used for evaluation. Finite element analysis was carried out for a double-legged stance. The comparative study indicated lesser stresses in head and neck region of the customised femoral stems than the standard implant. The study suggests design feasibility of customised implants for the Indian population owing to reduction in stresses in the implant.

  12. Análise da expansão rápida da maxila por meio da tomografia computadorizada Cone-Beam Analysis of rapid maxillary expansion using Cone-Beam computed tomography

    Directory of Open Access Journals (Sweden)

    Gerson Luiz Ulema Ribeiro

    2010-12-01

    Full Text Available Diante do diagnóstico de uma arcada maxilar esqueleticamente atrésica, o tratamento de escolha geralmente é a expansão ortopédica da maxila, envolvendo a separação da sutura palatina mediana. A avaliação dessa sutura era basicamente realizada por meio da radiografia oclusal superior, limitando sua análise em norma frontal. Da mesma forma, quantificar essa atresia radiograficamente nas telerradiografias cefalométricas sempre foi um obstáculo para o clínico, devido à grande sobreposição das estruturas faciais. O advento da tomografia computadorizada na Odontologia tem transformado a forma de diagnóstico devido à alta precisão na avaliação das dimensões das estruturas faciais, possibilitando quantificar de maneira fiel o comportamento das hemimaxilas, a inclinação dentária, a formação óssea na sutura nos três planos do espaço, assim como a reabsorção óssea alveolar e demais consequências da expansão palatinaWhenever a maxillary arch is diagnosed as skeletally atresic the treatment of choice is usually maxillary orthopedic expansion, involving separation of the midpalatal suture. Basically, this suture used to be assessed with the aid of a maxillary occlusal radiograph, which limited its posteroanterior evaluation. Similarly, quantifying this atresia in cephalometric x-rays always posed an obstacle for clinicians owing to considerable superimposition of facial structures. With the advent of computed tomography, this technology has revolutionized diagnostic methods in dentistry because it provides high dimensional accuracy of the facial structures and a reliable method for quantifying the behavior of the maxillary halves, tooth inclination, bone formation at the suture in the three planes of space, as well as alveolar bone resorption and other consequences of palatal expansion

  13. Two populations of amphibole in dacite magmas at Volcan Aucanquilcha, Chile: A case for rapid and repeated mixing of a tiered magmatic system

    Science.gov (United States)

    Klemetti, E. W.; Grunder, A. L.

    2006-12-01

    Magmatic amphibole is a ubiquitous phase in most dacitic magmas in continental arc systems. Amphibole can react quickly to changes in P, T and water content caused by processes such as underplating of new magma, degassing, ascension and mixing of magma. This allows amphibole to be a valuable and sensitive barometer, thermometer and hygrometer in silicic magmatic systems. It can be especially suitable for disentangling the potential geometry of subvolcanic systems and limiting the timescales that these processes can occur. Volcán Aucanquilcha (Chile) is a Quaternary volcano that has erupted dacite lavas (63-67 wt% SiO2) that contain two populations of amphibole during its entire 1 M.y. eruptive history. The amphibole is found as phenocrysts of hornblende and pargasite that range in size from 0.5 mm to 1 cm. The amphibole populations exhibit a variety of textures: (1) thin opacite rims; (2) thick reaction rims of pyroxene, plagioclase and opaque oxides; (3) cored" with other phases such as plagioclase, biotite and anhydride; and (4) unrimmed. Representative electron microprobe analyses of amphibole find that very few of the phenocrysts are compositionally zoned, i.e., the two populations are not pargasite cores with hornblende rims. The presence of two populations of amphibole such as those found at Aucanquilcha appears to be rare; there are documented occurrences of two amphibole populations found in lavas from continental-arc related volcanoes. Sajama, Parinacota and Porquesa in Central Andes of Chile exhibit the same two populations of amphibole phenocrysts as Aucanquilcha. Evidence from Aucanquilcha suggest that the populations of amphibole crystallized at different pressures: 0.5-2 kb and 3-6 kb. Textures of the amphibole imply that the processes that mix the amphibole occur quickly before eruption, possibly in a timescales of days. The constant presence of these amphibole in all Aucanquilcha lavas indicate that the processes that juxtapose pargasite and

  14. How did Japanese rural dwellers become rapidly healthier in the two decades following World War II?: Examining the diverse policy interventions that improved the population's health.

    Science.gov (United States)

    Yuasa, Motoyuki

    2017-01-01

    policies implemented in Japan as well as the integration of various policies and programs addressing livelihoods, economics, and education greatly improved the population's health in a relatively short time. These non-health initiatives intersected with a wide range of health determinants. Verifying these hypotheses in detail would help develop effective measures for international aid to poverty-stricken regions. It also encourages alternative ways through which Japan could overcome its present-day challenges such as a rapidly aging population with limited access to national schemes for social security.

  15. Large sequence divergence of mitochondrial DNA genotypes of the control region within populations of the African antelope, kob (Kobus kob)

    DEFF Research Database (Denmark)

    Birungi, J.; Arctander, Peter

    2000-01-01

    conservation genetics, control region, Kobus kob, mitochondrial DNA, population expansion, population structure......conservation genetics, control region, Kobus kob, mitochondrial DNA, population expansion, population structure...

  16. Effect of rapid maxillary expansion on the dimension of the nasal cavity and on facial morphology assessed by acoustic rhinometry and rhinomanometry Efeito da expansão rápida da maxila na dimensão da cavidade nasal e morfologia facial pela rinometria acústica e rinomanometria

    Directory of Open Access Journals (Sweden)

    Carla Enoki Itikawa

    2012-08-01

    Full Text Available OBJECTIVE: To assess the effects of rapid maxillary expansion on facial morphology and on nasal cavity dimensions of mouth breathing children by acoustic rhinometry and computed rhinomanometry. METHODS: Cohort; 29 mouth breathing children with posterior crossbite were evaluated. Orthodontic and otorhinolaryngologic documentation were performed at three different times, i.e., before expansion, immediately after and 90 days following expansion. RESULTS: The expansion was accompanied by an increase of the maxillary and nasal bone transversal width. However, there were no significant differences in relation to mucosal area of the nose. Acoustic rhinometry showed no difference in the minimal cross-sectional area at the level of the valve and inferior turbinate between the periods analyzed, although rhinomanometry showed a statistically significant reduction in nasal resistance right after expansion, but were similar to pre-treatment values 90 days after expansion. CONCLUSION: The maxillary expansion increased the maxilla and nasal bony area, but was inefficient to increase the nasal mucosal area, and may lessen the nasal resistance, although there was no difference in nasal geometry. Significance: Nasal bony expansion is followed by a mucosal compensation.OBJETIVO: avaliar o efeito da expansão rápida da maxila na dimensão da cavidade nasal e na morfologia facial através da rinometria acústica e rinomanometria computadorizada. MÉTODOS: foram avaliadas 29 crianças na fase de dentição mista, portadoras de respiração bucal e mordida cruzada posterior. A documentação ortodôntica e a avaliação otorrinolaringológica foram realizadas em três tempos - antes da expansão rápida da maxila, imediatamente após e 90 dias depois. RESULTADOS: a expansão promoveu um aumento na dimensão da cavidade nasal e na maxila transversalmente. Contudo, não houve diferenças significativas na área da mucosa nasal. A rinometria acústica mostrou que n

  17. A population-based cross-sectional study of barriers to uptake of eye care services in South India: the Rapid Assessment of Visual Impairment (RAVI) project.

    Science.gov (United States)

    Marmamula, Srinivas; Khanna, Rohit C; Shekhar, Konegari; Rao, Gullapalli N

    2014-06-12

    To assess the barriers to uptake of eye care services among those with avoidable impairment in the population aged ≥40 years in the South Indian state of Andhra Pradesh. Cross-sectional study. Community setting. Of 7800 participants recruited from one urban and two rural locations using a two-stage cluster random sampling methodology, 7378 (95%) were examined. Eye examinations were conducted using a rapid assessment protocol. Visual impairment (VI) was defined as presenting visual acuity attitude and 'felt need' to improve vision, newer and much intensive awareness campaigns are needed to bring about an attitudinal/behavioural change among individuals to improve the uptake of services. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  18. Did the Higgs boson drive the universe's expansion?

    CERN Multimedia

    2008-01-01

    The Higgs boson has been moonlighting. Not content with its day job of giving other particles their mass, it may also have driven the expansion of the early universe, given a little tinkering, according to two separate studies. Soon after the big bang the early universe is believed to have undergone a period of rapid expansion, known as inflation.

  19. Conformal expansions and renormalons

    CERN Document Server

    Brodsky, S J; Grunberg, G; Rathsman, J; Brodsky, Stanley J.; Gardi, Einan; Grunberg, Georges; Rathsman, Johan

    2001-01-01

    The coefficients in perturbative expansions in gauge theories are factoriallyincreasing, predominantly due to renormalons. This type of factorial increaseis not expected in conformal theories. In QCD conformal relations betweenobservables can be defined in the presence of a perturbative infraredfixed-point. Using the Banks-Zaks expansion we study the effect of thelarge-order behavior of the perturbative series on the conformal coefficients.We find that in general these coefficients become factorially increasing.However, when the factorial behavior genuinely originates in a renormalonintegral, as implied by a postulated skeleton expansion, it does not affect theconformal coefficients. As a consequence, the conformal coefficients willindeed be free of renormalon divergence, in accordance with previousobservations concerning the smallness of these coefficients for specificobservables. We further show that the correspondence of the BLM method with theskeleton expansion implies a unique scale-setting procedure. Th...

  20. Gene expression under thermal stress varies across a geographical range expansion front.

    Science.gov (United States)

    Lancaster, Lesley T; Dudaniec, Rachael Y; Chauhan, Pallavi; Wellenreuther, Maren; Svensson, Erik I; Hansson, Bengt

    2016-03-01

    Many ectothermic species are currently expanding their distributions polewards due to anthropogenic global warming. Molecular genetic mechanisms facilitating range expansion under these conditions are largely unknown, but understanding these could help mitigate expanding pests and disease vectors, or help explain why some species fail to track changing climates. Here, using RNA-seq data, we examine genomewide changes in gene expression under heat and cold stress in the range-expanding damselfly Ischnura elegans in northern Europe. We find that both the number of genes involved and levels of gene expression under heat stress have become attenuated during the expansion, consistent with a previously reported release from selection on heat tolerances as species move polewards. Genes upregulated under cold stress differed between core and edge populations, corroborating previously reported rapid adaptation to cooler climates at the expansion front. Expression of sixty-nine genes exhibited a region x treatment effect; these were primarily upregulated in response to heat stress in core populations but in response to cold stress at the range edge, suggesting that some cellular responses originally adapted to heat stress may switch to cold-stress functionality upon encountering novel thermal selection regimes during range expansion. Transcriptional responses to thermal stress involving heat-shock and neural function genes were largely geographically conserved, while retrotransposon, regulatory, muscle function and defence gene expression patterns were more variable. Flexible mechanisms of cold-stress response and the ability of some genes to shift their function between heat and cold stress might be key mechanisms facilitating rapid poleward expansion in insects. © 2016 John Wiley & Sons Ltd.

  1. Rapid and accurate species and genomic species identification and exhaustive population diversity assessment of Agrobacterium spp. using recA-based PCR.

    Science.gov (United States)

    Shams, M; Vial, L; Chapulliot, D; Nesme, X; Lavire, C

    2013-07-01

    Agrobacteria are common soil bacteria that interact with plants as commensals, plant growth promoting rhizobacteria or alternatively as pathogens. Indigenous agrobacterial populations are composites, generally with several species and/or genomic species and several strains per species. We thus developed a recA-based PCR approach to accurately identify and specifically detect agrobacteria at various taxonomic levels. Specific primers were designed for all species and/or genomic species of Agrobacterium presently known, including 11 genomic species of the Agrobacterium tumefaciens complex (G1-G9, G13 and G14, among which only G2, G4, G8 and G14 still received a Latin epithet: pusense, radiobacter, fabrum and nepotum, respectively), A. larrymoorei, A. rubi, R. skierniewicense, A. sp. 1650, and A. vitis, and for the close relative Allorhizobium undicola. Specific primers were also designed for superior taxa, Agrobacterium spp. and Rhizobiaceace. Primer specificities were assessed with target and non-target pure culture DNAs as well as with DNAs extracted from composite agrobacterial communities. In addition, we showed that the amplicon cloning-sequencing approach used with Agrobacterium-specific or Rhizobiaceae-specific primers is a way to assess the agrobacterial diversity of an indigenous agrobacterial population. Hence, the agrobacterium-specific primers designed in the present study enabled the first accurate and rapid identification of all species and/or genomic species of Agrobacterium, as well as their direct detection in environmental samples. Copyright © 2013 Elsevier GmbH. All rights reserved.

  2. Multiplex Minisequencing of the HBB Gene: A Rapid Strategy to Confirm the Most Frequent β-Thalassemia Mutations in the Tunisian Population.

    Science.gov (United States)

    Ben Charfeddine, Ilhem; Ben Lazreg, Taheni; M'sakni, Ahlem; Amara, Abdelbasset; Mlika, Adnène; Chaïeb, Anouar; Hlel, Khalid; Zouari, Noura; Zbidi, Faïza; Bouguila, Jihène; Soyah, Najla; Ayedi, Abdelkarim; Ben Hamouda, Hechmi; Abroug, Saoussen; Boughamoura, Lamia; Saad, Ali; Gribaa, Moez

    2015-01-01

    The β hemoglobinopathies [β-thalassemia (β-thal) and structural hemoglobin (Hb) variants such as Hb S (HBB: c.20A > T) and Hb E (HBB: c.79G > A)] are among the most common inherited diseases worldwide. In Tunisia, due to the high prevalence of consanguineous marriages, the recurrent risk of this disease is high. The average prevalence of hemoglobinopathies is 4.48%, reaching 12.50% in some focus regions. The molecular investigations on thalassemia contributed to establishing the spectrum of mutations in the Tunisian population. The total number of HBB gene mutations identified was 24. The two most frequent mutations, codon 39 (C > T) (HBB: c.118C > T) and IVS-I-110 (G > A) (HBB: c.93-21G > A) accounted for 70.0% of the total encountered β-thal cases. These two mutations together with IVS-I-2 (T > G) (HBB: c.92 + 2T > G) and the Hb S variant account for more than 90.0% of all HBB genetic variants in Tunisia. Thus, developing rapid, inexpensive and reliable mutation-specific molecular diagnostic assays targeting our Tunisian populations is our aim to facilitate routine detection of hemoglobinopathies. In this report, we describe the successful application of the multiplex minisequencing assay as an alternative strategy for genetic diagnosis of HBB gene disorders in Tunisia.

  3. Estudo das alterações craniofaciais e da importância da expansão rápida da maxila após adenotonsilectomia Study of craniofacial alterations and of the importance of the rapid maxillary expansion after tonsillectomy

    Directory of Open Access Journals (Sweden)

    Silvia Regina Amorim Pereira

    2012-04-01

    Full Text Available A hipertrofia obstrutiva das tonsilas palatinas e faríngeas está associada à respiração oral e pode levar a desequilíbrios faciais. A adenotonsilectomia parece ser insuficiente para o tratamento quando ocorreram alterações anatômicas. Técnicas ortopédicas faciais auxiliam no restabelecimento morfofuncional. Estudo clínico longitudinal prospectivo objetivou observar alterações craniofaciais após adenotonsilectomia e verificar a importância de associar ortopedia ao tratamento. MATERIAL E MÉTODO: Cinquenta e três crianças de ambos os gêneros, entre 6 e 12 anos, divididas em: Grupo 1, 20 crianças com respiração nasal; Grupo 2, 33 crianças com hipertrofia obstrutiva das tonsilas faríngeas e/ou palatinas, submetidas à adenotonsilectomia. Após a cirurgia, este grupo foi subdividido: Grupo 2A, 16 pacientes não tratados com expansão rápida da maxila; Grupo 2B, 17 pacientes tratados com disjunção maxilar. Foram realizadas medidas cefalométricas em norma frontal e lateral anteriores à cirurgia e após 14 meses. Foram utilizados os testes Kruskal-Wallis e Wilcoxon, com nível de significância de 5%. RESULTADOS: A adenotonsilectomia equilibrou o crescimento transversal, sagital e vertical em ambos os grupos, sendo mais efetiva no grupo submetido ao tratamento combinado. CONCLUSÕES: A adenotonsilectomia favoreceu o crescimento facial das crianças com hipertrofia obstrutiva, sendo mais evidente quando associada à expansão maxilar.Obstructive hypertrophy of the tonsils and/or adenoids is associated with mouth breathing and can lead to facial imbalances. Adenotonsillectomy is not enough to treat the anatomic changes. Facial orthopedic techniques aid in morphological and functional recovery. This prospective longitudinal clinical study aimed to observe craniofacial changes after adenotonsillectomy and to verify the importance of linking rapid maxillary expansion to treatment. METHOD: Fifty-three children of both genders

  4. Population distribution, density and habitat preference of the Cerulean Warbler (Setophaga cerulea) in the Delaware Water Gap National Recreation Area

    Science.gov (United States)

    Shannon Curley; Terry Master; Gregory George

    2012-01-01

    The breeding range of the Cerulean Warbler has expanded into second-growth forest and converted agricultural land in the northeastern United States where, according to the North American Breeding Bird Survey, the population is increasing. Despite this expansion in one part of its range, the population as a whole is still in rapid decline implying that habitat quality...

  5. An ultra-high density bin-map for rapid QTL mapping for tassel and ear architecture in a large F₂ maize population.

    Science.gov (United States)

    Chen, Zongliang; Wang, Baobao; Dong, Xiaomei; Liu, Han; Ren, Longhui; Chen, Jian; Hauck, Andrew; Song, Weibin; Lai, Jinsheng

    2014-06-04

    Understanding genetic control of tassel and ear architecture in maize (Zea mays L. ssp. mays) is important due to their relationship with grain yield. High resolution QTL mapping is critical for understanding the underlying molecular basis of phenotypic variation. Advanced populations, such as recombinant inbred lines, have been broadly adopted for QTL mapping; however, construction of large advanced generation crop populations is time-consuming and costly. The rapidly declining cost of genotyping due to recent advances in next-generation sequencing technologies has generated new possibilities for QTL mapping using large early generation populations. A set of 708 F2 progeny derived from inbreds Chang7-2 and 787 were generated and genotyped by whole genome low-coverage genotyping-by-sequencing method (average 0.04×). A genetic map containing 6,533 bin-markers was constructed based on the parental SNPs and a sliding-window method, spanning a total genetic distance of 1,396 cM. The high quality and accuracy of this map was validated by the identification of two well-studied genes, r1, a qualitative trait locus for color of silk (chromosome 10) and ba1 for tassel branch number (chromosome 3). Three traits of tassel and ear architecture were evaluated in this population, a total of 10 QTL were detected using a permutation-based-significance threshold, seven of which overlapped with reported QTL. Three genes (GRMZM2G316366, GRMZM2G492156 and GRMZM5G805008) encoding MADS-box domain proteins and a BTB/POZ domain protein were located in the small intervals of qTBN5 and qTBN7 (~800 Kb and 1.6 Mb in length, respectively) and may be involved in patterning of tassel architecture. The small physical intervals of most QTL indicate high-resolution mapping is obtainable with this method. We constructed an ultra-high-dentisy linkage map for the large early generation population in maize. Our study provides an efficient approach for fast detection of quantitative loci responsible

  6. Resonant state expansions

    Energy Technology Data Exchange (ETDEWEB)

    Lind, P.

    1993-02-01

    The completeness properties of the discrete set of bound state, virtual states and resonances characterizing the system of a single nonrelativistic particle moving in a central cutoff potential is investigated. From a completeness relation in terms of these discrete states and complex scattering states one can derive several Resonant State Expansions (RSE). It is interesting to obtain purely discrete expansion which, if valid, would significantly simplify the treatment of the continuum. Such expansions can be derived using Mittag-Leffler (ML) theory for a cutoff potential and it would be nice to see if one can obtain the same expansions starting from an eigenfunction theory that is not restricted to a finite sphere. The RSE of Greens functions is especially important, e.g. in the continuum RPA (CRPA) method of treating giant resonances in nuclear physics. The convergence of RSE is studied in simple cases using square well wavefunctions in order to achieve high numerical accuracy. Several expansions can be derived from each other by using the theory of analytic functions and one can the see how to obtain a natural discretization of the continuum. Since the resonance wavefunctions are oscillating with an exponentially increasing amplitude, and therefore have to be interpreted through some regularization procedure, every statement made about quantities involving such states is checked by numerical calculations.Realistic nuclear wavefunctions, generated by a Wood-Saxon potential, are used to test also the usefulness of RSE in a realistic nuclear calculation. There are some fundamental differences between different symmetries of the integral contour that defines the continuum in RSE. One kind of symmetry is necessary to have an expansion of the unity operator that is idempotent. Another symmetry must be used if we want purely discrete expansions. These are found to be of the same form as given by ML. (29 refs.).

  7. Expansion of protein domain repeats.

    Directory of Open Access Journals (Sweden)

    Asa K Björklund

    2006-08-01

    Full Text Available Many proteins, especially in eukaryotes, contain tandem repeats of several domains from the same family. These repeats have a variety of binding properties and are involved in protein-protein interactions as well as binding to other ligands such as DNA and RNA. The rapid expansion of protein domain repeats is assumed to have evolved through internal tandem duplications. However, the exact mechanisms behind these tandem duplications are not well-understood. Here, we have studied the evolution, function, protein structure, gene structure, and phylogenetic distribution of domain repeats. For this purpose we have assigned Pfam-A domain families to 24 proteomes with more sensitive domain assignments in the repeat regions. These assignments confirmed previous findings that eukaryotes, and in particular vertebrates, contain a much higher fraction of proteins with repeats compared with prokaryotes. The internal sequence similarity in each protein revealed that the domain repeats are often expanded through duplications of several domains at a time, while the duplication of one domain is less common. Many of the repeats appear to have been duplicated in the middle of the repeat region. This is in strong contrast to the evolution of other proteins that mainly works through additions of single domains at either terminus. Further, we found that some domain families show distinct duplication patterns, e.g., nebulin domains have mainly been expanded with a unit of seven domains at a time, while duplications of other domain families involve varying numbers of domains. Finally, no common mechanism for the expansion of all repeats could be detected. We found that the duplication patterns show no dependence on the size of the domains. Further, repeat expansion in some families can possibly be explained by shuffling of exons. However, exon shuffling could not have created all repeats.

  8. Agricultural expansion and its impacts on tropical nature.

    Science.gov (United States)

    Laurance, William F; Sayer, Jeffrey; Cassman, Kenneth G

    2014-02-01

    The human population is projected to reach 11 billion this century, with the greatest increases in tropical developing nations. This growth, in concert with rising per-capita consumption, will require large increases in food and biofuel production. How will these megatrends affect tropical terrestrial and aquatic ecosystems and biodiversity? We foresee (i) major expansion and intensification of tropical agriculture, especially in Sub-Saharan Africa and South America; (ii) continuing rapid loss and alteration of tropical old-growth forests, woodlands, and semi-arid environments; (iii) a pivotal role for new roadways in determining the spatial extent of agriculture; and (iv) intensified conflicts between food production and nature conservation. Key priorities are to improve technologies and policies that promote more ecologically efficient food production while optimizing the allocation of lands to conservation and agriculture. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Comportamento da sutura palatina mediana em crianças submetidas à expansão rápida da maxila: avaliação mediante imagem de tomografia computadorizada Behavior of the midpalatal suture in children submitted to rapid maxillary expansion: evaluation with computerized tomography

    Directory of Open Access Journals (Sweden)

    Omar Gabriel da Silva Filho

    2007-06-01

    Full Text Available OBJETIVO: o presente estudo, de caráter prospectivo, objetivou avaliar a imagem da sutura palatina mediana em crianças submetidas à expansão rápida da maxila por meio de tomografia computadorizada, após a fase de contenção. METODOLOGIA: a amostra constou de 17 crianças de ambos os gêneros, na faixa etária compreendida entre 5 anos e 2 meses e 10 anos e 5 meses no início do tratamento, provenientes da Clínica de Ortodontia Interceptiva da Sociedade de Promoção Social do Fissurado Lábio-Palatal da Universidade de São Paulo (PROFIS-USP, Bauru/SP. Tomografias computadorizadas foram implementadas para avaliar o comportamento da sutura palatina mediana em diferentes momentos do tratamento. RESULTADOS E CONCLUSÕES: constatou-se que, após um período médio de 8 a 9 meses de contenção com o aparelho expansor, a sutura palatina mediana mostrou-se completamente ossificada, desde a região da espinha nasal anterior até a espinha nasal posterior. Tal informação esclarece o comportamento da sutura palatina mediana frente à expansão rápida da maxila e reitera o senso comum quanto ao caráter biológico do procedimento.AIM: The aim of this prospective study was to evaluate the midpalatal suture in children submitted to rapid palatal expansion with computerized tomography. METHODS: The sample was comprised of 17 children aged between 5 years and 2 months and 10 years and 5 months, that were submited to rapid palatal expansion. The radiologic aspect of the sutures were evaluated through computerized tomography. RESULS AND CONCLUSIONS: The tomographic images showed that, after the retention phase (8 to 9 months post-expansion, the midpalatal suture was completely ossified from the anterior to the posterior nasal spine region.

  10. Virial Expansion Bounds

    Science.gov (United States)

    Tate, Stephen James

    2013-10-01

    In the 1960s, the technique of using cluster expansion bounds in order to achieve bounds on the virial expansion was developed by Lebowitz and Penrose (J. Math. Phys. 5:841, 1964) and Ruelle (Statistical Mechanics: Rigorous Results. Benjamin, Elmsford, 1969). This technique is generalised to more recent cluster expansion bounds by Poghosyan and Ueltschi (J. Math. Phys. 50:053509, 2009), which are related to the work of Procacci (J. Stat. Phys. 129:171, 2007) and the tree-graph identity, detailed by Brydges (Phénomènes Critiques, Systèmes Aléatoires, Théories de Jauge. Les Houches 1984, pp. 129-183, 1986). The bounds achieved by Lebowitz and Penrose can also be sharpened by doing the actual optimisation and achieving expressions in terms of the Lambert W-function. The different bound from the cluster expansion shows some improvements for bounds on the convergence of the virial expansion in the case of positive potentials, which are allowed to have a hard core.

  11. Wake Expansion Models

    DEFF Research Database (Denmark)

    Branlard, Emmanuel Simon Pierre

    2017-01-01

    Different models of wake expansion are presented in this chapter: the 1D momentum theory model, the cylinder analog model and Theodorsen’s model. Far wake models such as the ones from Frandsen or Rathmann or only briefly mentioned. The different models are compared to each other. Results from thi...... this chapter are used in Chap. 16 to link near-wake and far-wake parameters and in Chap. 20 to study the influence of expansion on tip-losses....

  12. Uniform gradient expansions

    Directory of Open Access Journals (Sweden)

    Massimo Giovannini

    2015-06-01

    Full Text Available Cosmological singularities are often discussed by means of a gradient expansion that can also describe, during a quasi-de Sitter phase, the progressive suppression of curvature inhomogeneities. While the inflationary event horizon is being formed the two mentioned regimes coexist and a uniform expansion can be conceived and applied to the evolution of spatial gradients across the protoinflationary boundary. It is argued that conventional arguments addressing the preinflationary initial conditions are necessary but generally not sufficient to guarantee a homogeneous onset of the conventional inflationary stage.

  13. Identification of a novel HLA-G+ regulatory population in blood: expansion after allogeneic transplantation and de novo HLA-G expression at graft-versus-host disease sites

    Science.gov (United States)

    Lazana, Ioanna; Zoudiari, Anastasia; Kokkinou, Dimitra; Themeli, Maria; Liga, Maria; Papadaki, Helen; Papachristou, Dionysios; Spyridonidis, Alexandros

    2012-01-01

    Background The human leukocyte antigen-G (HLA-G) has been considered to be an important tolerogeneic molecule playing an essential role in maternal-fetal tolerance, which constitutes the perfect example of successful physiological immunotolerance of semi-allografts. In this context, we investigated the putative role of this molecule in the allogeneic hematopoietic cell transplantation setting. Design and Methods The percentage of HLA-G+ cells in peripheral blood of healthy donors and allo-transplanted patients was evaluated by flow cytometry. Their immunoregulatory and tolerogeneic properties were investigated in in vitro immunostimulatory and immunosuppression assays. Immunohistochemical analysis for HLA-G expression was performed in skin biopsies from allo-transplanted patients and correlated with the occurrence of graft-versus-host disease. Results We identified a CD14+HLA-Gpos population with an HLA-DRlow phenotype and decreased in vitro immunostimulatory capacity circulating in peripheral blood of healthy individuals. Naturally occurring CD14+HLA-Gpos cells suppressed T-cell responses and exerted an immunotolerogenic action on T cells by rendering them hyporesponsive and immunosuppressive in vitro. After allogeneic hematopoietic cell transplantation, HLA-Gpos cells increase in blood. Interestingly, besides an increase in CD14+HLA-Gpos cells, there was also a pronounced expansion of CD3+HLA-Gpos cells. Of note, CD3+HLA-Gpos and CD14+HLA-Gpos cells from transplanted patients were suppressive in in vitro lymphoproliferation assays. Furthermore, we found an upregulation of HLA-G expression in skin specimens from transplanted patients that correlated with graft-versus-host disease. Inflammatory cells infiltrating the dermis of transplanted patients were also HLA-Gpos. Conclusions We report the presence of naturally occurring HLA-Gpos monocytic cells with in vitro suppressive properties. HLA-G expressing regulatory blood cells were found in increased numbers after

  14. Highly visible street-based HIV rapid testing: is it an attractive option for a previously untested population? A cross-sectional study.

    Science.gov (United States)

    Fernández-Balbuena, Sonia; de la Fuente, Luis; Hoyos, Juan; Rosales-Statkus, M Elena; Barrio, Gregorio; Belza, María-José

    2014-03-01

    Given the shortage of community-based HIV testing initiatives in resource-rich countries not targeting most-at-risk populations, we aimed to evaluate whether a highly visible mobile programme promoting and offering rapid HIV testing in the street can attract persons at risk for infection who have never been tested. Between 2008 and 2011, the programme served 7552 persons in various Spanish cities who answered a brief questionnaire while awaiting their results. The factors associated with being tested for the first time were analysed using two logistic regression models, one for men who have sex with men (MSM) and the other for only heterosexual men (MSW) and women. 3517 participants (47%) were first-time testers (24% of MSM, 56% of MSW and 60% of women). Among them, 22 undiagnosed HIV infections were detected with a global prevalence of 0.6% and 3.1% in MSM. Undergoing a first HIV test was independently associated with age gay community. Among those tested for the first time, 22% had never thought of being tested and 62% decided to be tested when they passed by and noticed the programme, regardless of their previous intentions. This community programme attracted a substantial number of persons previously untested and particularly hard to reach, such as those with low education and MSM who were least involved in the gay community. Programme visibility was a decisive factor for almost two of every three persons who had never been tested.

  15. Alcohol tax policy and related mortality. An age-period-cohort analysis of a rapidly developed Chinese population, 1981-2010.

    Science.gov (United States)

    Chung, Roger Y; Kim, Jean H; Yip, Benjamin H; Wong, Samuel Y S; Wong, Martin C S; Chung, Vincent C H; Griffiths, Sian M

    2014-01-01

    To delineate the temporal dynamics between alcohol tax policy changes and related health outcomes, this study examined the age, period and cohort effects on alcohol-related mortality in relation to changes in government alcohol policies. We used the age-period-cohort modeling to analyze retrospective mortality data over 30 years from 1981 to 2010 in a rapidly developed Chinese population, Hong Kong. Alcohol-related mortality from 1) chronic causes, 2) acute causes, 3) all (chronic+acute) causes and 4) causes 100% attributable to alcohol, as defined according to the Alcohol-Related Disease Impact (ARDI) criteria developed by the US Centers for Disease Control and Prevention, were examined. The findings illustrated the possible effects of alcohol policy changes on adult alcohol-related mortality. The age-standardized mortality trends were generally in decline, with fluctuations that coincided with the timing of the alcohol policy changes. The age-period-cohort analyses demonstrated possible temporal dynamics between alcohol policy changes and alcohol-related mortality through the period effects, and also generational impact of alcohol policy changes through the cohort effects. Based on the illustrated association between the dramatic increase of alcohol imports in the mid-1980s and the increased alcohol-related mortality risk of the generations coming of age of majority at that time, attention should be paid to generations coming of drinking age during the 2007-2008 duty reduction.

  16. Supercritical flow characteristics at abrupt expansion structure

    Science.gov (United States)

    Lim, Jia Jun; Puay, How Tion; Zakaria, Nor Azazi

    2017-10-01

    When dealing with the design of a hydraulic structure, lateral expansion is often necessary for flow emerging at high velocity served as a cross-sectional transition. If the abrupt expansion structure is made to diverge rapidly, it will cause the major part of the flow fail to follow the boundaries. If the transition is too gradual, it will result in a waste of structural material. A preliminary study on the flow structure near the expansion and its relationship with flow parameter is carried out in this study. A two-dimensional depth-averaged model is developed to simulate the supercritical flow at the abrupt expansion structure. Constrained Interpolation Profile (CIP) scheme (which is of third order accuracy) is adopted in the numerical