WorldWideScience

Sample records for underpin population variability

  1. Impacts of Climate Variability and Change on (Marine) Animals: Physiological Underpinnings and Evolutionary Consequences.

    Science.gov (United States)

    Pörtner, Hans O; Gutt, Julian

    2016-07-01

    Understanding thermal ranges and limits of organisms becomes important in light of climate change and observed effects on ecosystems as reported by the IPCC (2014). Evolutionary adaptation to temperature is presently unable to keep animals and other organisms in place; if they can these rather follow the moving isotherms. These effects of climate change on aquatic and terrestrial ecosystems have brought into focus the mechanisms by which temperature and its oscillations shape the biogeography and survival of species. For animals, the integrative concept of oxygen and capacity limited thermal tolerance (OCLTT) has successfully characterized the sublethal limits to performance and the consequences of such limits for ecosystems. Recent models illustrate how routine energy demand defines the realized niche. Steady state temperature-dependent performance profiles thus trace the thermal window and indicate a key role for aerobic metabolism, and the resulting budget of available energy (power), in defining performance under routine conditions, from growth to exercise and reproduction. Differences in the performance and productivity of marine species across latitudes relate to changes in mitochondrial density, capacity, and other features of cellular design. Comparative studies indicate how and why such mechanisms underpinning OCLTT may have developed on evolutionary timescales in different climatic zones and contributed to shaping the functional characteristics and species richness of the respective fauna. A cause-and-effect understanding emerges from considering the relationships between fluctuations in body temperature, cellular design, and performance. Such principles may also have been involved in shaping the functional characteristics of survivors in mass extinction events during earth's history; furthermore, they may provide access to understanding the evolution of endothermy in mammals and birds. Accordingly, an understanding is emerging how climate changes and

  2. The underpinnings.

    Science.gov (United States)

    Fudge, L

    2001-03-01

    In last month's Journal, readers were introduced to the government's Improving Working Lives Strategy. This month some of the underpinning detail will be examined in order to show what is expected from employers and employees when getting the balance right between work and life away from work.

  3. Population dynamics in variable environments

    CERN Document Server

    Tuljapurkar, Shripad

    1990-01-01

    Demography relates observable facts about individuals to the dynamics of populations. If the dynamics are linear and do not change over time, the classical theory of Lotka (1907) and Leslie (1945) is the central tool of demography. This book addresses the situation when the assumption of constancy is dropped. In many practical situations, a population will display unpredictable variation over time in its vital rates, which must then be described in statistical terms. Most of this book is concerned with the theory of populations which are subject to random temporal changes in their vital rates, although other kinds of variation (e. g. , cyclical) are also dealt with. The central questions are: how does temporal variation work its way into a population's future, and how does it affect our interpretation of a population's past. The results here are directed at demographers of humans and at popula­ tion biologists. The uneven mathematical level is dictated by the material, but the book should be accessible to re...

  4. Heart rate variability in healthy population

    International Nuclear Information System (INIS)

    Alamgir, M.; Hussain, M.M.

    2010-01-01

    Background: Heart rate variability has been considered as an indicator of autonomic status. Little work has been done on heart rate variability in normal healthy volunteers. We aimed at evolving the reference values of heart rate variability in our healthy population. Methods: Twenty-four hour holter monitoring of 37 healthy individuals was done using Holter ECG recorder 'Life card CF' from 'Reynolds Medical'. Heart rate variability in both time and frequency domains was analysed with 'Reynolds Medical Pathfinder Digital/700'. Results: The heart rate variability in normal healthy volunteers of our population was found in time domain using standard deviation of R-R intervals (SDNN), standard deviation of average NN intervals (SDANN), and Square root of the mean squared differences of successive NN intervals (RMSSD). Variation in heart rate variability indices was observed between local and foreign volunteers and RMSSD was found significantly increased (p<0.05) in local population. Conclusions: The values of heart rate variability (RMSSD) in healthy Pakistani volunteers were found increased compared to the foreign data reflecting parasympathetic dominance in our population. (author)

  5. Photometric Variability of the Be Star Population

    Energy Technology Data Exchange (ETDEWEB)

    Labadie-Bartz, Jonathan; Pepper, Joshua; McSwain, M. Virginia [Department of Physics, Lehigh University, 16 Memorial Drive East, Bethlehem, PA 18015 (United States); Bjorkman, J. E.; Bjorkman, K. S. [Ritter Observatory, Department of Physics and Astronomy, University of Toledo, 2801 W. Bancroft, Toledo, OH 43606-3390 (United States); Lund, Michael B.; Rodriguez, Joseph E.; Stassun, Keivan G. [Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235 (United States); Stevens, Daniel J. [Department of Astronomy, The Ohio State University, 140 W. 18th Avenue, Columbus, OH 43210 (United States); James, David J. [Cerro Tololo Inter-American Observatory, Casilla 603 La Serena (Chile); Kuhn, Rudolf B. [Southern African Large Telescope, P.O. Box 9, Observatory 7935, Cape Town (South Africa); Siverd, Robert J. [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Drive, Suite 102, Santa Barbara, CA 93117 (United States); Beatty, Thomas G. [Department of Astronomy and Astrophysics, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802 (United States)

    2017-06-01

    Be stars have generally been characterized by the emission lines in their spectra, and especially the time variability of those spectroscopic features. They are known to also exhibit photometric variability at multiple timescales, but have not been broadly compared and analyzed by that behavior. We have taken advantage of the advent of wide-field, long-baseline, and high-cadence photometric surveys that search for transiting exoplanets to perform a comprehensive analysis of brightness variations among a large number of known Be stars. The photometric data comes from the KELT transit survey, with a typical cadence of 30 minutes, a baseline of up to 10 years, photometric precision of about 1%, and coverage of about 60% of the sky. We analyze KELT light curves of 610 known Be stars in both the northern and southern hemispheres in an effort to study their variability. Consistent with other studies of Be star variability, we find most of the stars to be photometrically variable. We derive lower limits on the fraction of stars in our sample that exhibit features consistent with non-radial pulsations (25%), outbursts (36%), and long-term trends in the circumstellar disk (37%), and show how these are correlated with spectral sub-types. Other types of variability, such as those owing to binarity, are also explored. Simultaneous spectroscopy for some of these systems from the Be Star Spectra database allow us to better understand the physical causes for the observed variability, especially in cases of outbursts and changes in the disk.

  6. Photometric Variability of the Be Star Population

    International Nuclear Information System (INIS)

    Labadie-Bartz, Jonathan; Pepper, Joshua; McSwain, M. Virginia; Bjorkman, J. E.; Bjorkman, K. S.; Lund, Michael B.; Rodriguez, Joseph E.; Stassun, Keivan G.; Stevens, Daniel J.; James, David J.; Kuhn, Rudolf B.; Siverd, Robert J.; Beatty, Thomas G.

    2017-01-01

    Be stars have generally been characterized by the emission lines in their spectra, and especially the time variability of those spectroscopic features. They are known to also exhibit photometric variability at multiple timescales, but have not been broadly compared and analyzed by that behavior. We have taken advantage of the advent of wide-field, long-baseline, and high-cadence photometric surveys that search for transiting exoplanets to perform a comprehensive analysis of brightness variations among a large number of known Be stars. The photometric data comes from the KELT transit survey, with a typical cadence of 30 minutes, a baseline of up to 10 years, photometric precision of about 1%, and coverage of about 60% of the sky. We analyze KELT light curves of 610 known Be stars in both the northern and southern hemispheres in an effort to study their variability. Consistent with other studies of Be star variability, we find most of the stars to be photometrically variable. We derive lower limits on the fraction of stars in our sample that exhibit features consistent with non-radial pulsations (25%), outbursts (36%), and long-term trends in the circumstellar disk (37%), and show how these are correlated with spectral sub-types. Other types of variability, such as those owing to binarity, are also explored. Simultaneous spectroscopy for some of these systems from the Be Star Spectra database allow us to better understand the physical causes for the observed variability, especially in cases of outbursts and changes in the disk.

  7. Stability of termite mound populations in a variable environment ...

    African Journals Online (AJOL)

    Of all the climatic variables in the environment of termites in southern Kenya, only rainfall shows marked seasonality and unpredictability. But despite the great variability in rainfall patterns, the populations of termite mounds of various species in three well-separated study areas remained remarkably constant over a period ...

  8. A new population growth map with variable coefficients

    International Nuclear Information System (INIS)

    Jannussis, A.

    1986-01-01

    In the present paper it is investigated a simple population growth map with variable coefficients. Moreover, it is studied the new population map of the form xsub(j+1) = axsub(j) (1/(1 + bxsub(j)) -1/(1 + cxsub(j))), c not= b, j = 0, 1,..., which is transformed in an equivalent logistic map

  9. Using variable combination population analysis for variable selection in multivariate calibration.

    Science.gov (United States)

    Yun, Yong-Huan; Wang, Wei-Ting; Deng, Bai-Chuan; Lai, Guang-Bi; Liu, Xin-bo; Ren, Da-Bing; Liang, Yi-Zeng; Fan, Wei; Xu, Qing-Song

    2015-03-03

    Variable (wavelength or feature) selection techniques have become a critical step for the analysis of datasets with high number of variables and relatively few samples. In this study, a novel variable selection strategy, variable combination population analysis (VCPA), was proposed. This strategy consists of two crucial procedures. First, the exponentially decreasing function (EDF), which is the simple and effective principle of 'survival of the fittest' from Darwin's natural evolution theory, is employed to determine the number of variables to keep and continuously shrink the variable space. Second, in each EDF run, binary matrix sampling (BMS) strategy that gives each variable the same chance to be selected and generates different variable combinations, is used to produce a population of subsets to construct a population of sub-models. Then, model population analysis (MPA) is employed to find the variable subsets with the lower root mean squares error of cross validation (RMSECV). The frequency of each variable appearing in the best 10% sub-models is computed. The higher the frequency is, the more important the variable is. The performance of the proposed procedure was investigated using three real NIR datasets. The results indicate that VCPA is a good variable selection strategy when compared with four high performing variable selection methods: genetic algorithm-partial least squares (GA-PLS), Monte Carlo uninformative variable elimination by PLS (MC-UVE-PLS), competitive adaptive reweighted sampling (CARS) and iteratively retains informative variables (IRIV). The MATLAB source code of VCPA is available for academic research on the website: http://www.mathworks.com/matlabcentral/fileexchange/authors/498750. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Barn Owl Productivity Response to Variability of Vole Populations.

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    Petr Pavluvčík

    Full Text Available We studied the response of the barn owl annual productivity to the common vole population numbers and variability to test the effects of environmental stochasticity on their life histories. Current theory predicts that temporal environmental variability can affect long-term nonlinear responses (e.g., production of young both positively and negatively, depending on the shape of the relationship between the response and environmental variables. At the level of the Czech Republic, we examined the shape of the relationship between the annual sum of fledglings (annual productivity and vole numbers in both non-detrended and detrended data. At the districts' level, we explored whether the degree of synchrony (measured by the correlation coefficient and the strength of the productivity response increase (measured by the regression coefficient in areas with higher vole population variability measured by the s-index. We found that the owls' annual productivity increased linearly with vole numbers in the Czech Republic. Furthermore, based on district data, we also found that synchrony between dynamics in owls' reproductive output and vole numbers increased with vole population variability. However, the strength of the response was not affected by the vole population variability. Additionally, we have shown that detrending remarkably increases the Taylor's exponent b relating variance to mean in vole time series, thereby reversing the relationship between the coefficient of variation and the mean. This shift was not responsible for the increased synchrony with vole population variability. Instead, we suggest that higher synchrony could result from high food specialization of owls on the common vole in areas with highly fluctuating vole populations.

  11. Variable mutation rates as an adaptive strategy in replicator populations.

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    Michael Stich

    2010-06-01

    Full Text Available For evolving populations of replicators, there is much evidence that the effect of mutations on fitness depends on the degree of adaptation to the selective pressures at play. In optimized populations, most mutations have deleterious effects, such that low mutation rates are favoured. In contrast to this, in populations thriving in changing environments a larger fraction of mutations have beneficial effects, providing the diversity necessary to adapt to new conditions. What is more, non-adapted populations occasionally benefit from an increase in the mutation rate. Therefore, there is no optimal universal value of the mutation rate and species attempt to adjust it to their momentary adaptive needs. In this work we have used stationary populations of RNA molecules evolving in silico to investigate the relationship between the degree of adaptation of an optimized population and the value of the mutation rate promoting maximal adaptation in a short time to a new selective pressure. Our results show that this value can significantly differ from the optimal value at mutation-selection equilibrium, being strongly influenced by the structure of the population when the adaptive process begins. In the short-term, highly optimized populations containing little variability respond better to environmental changes upon an increase of the mutation rate, whereas populations with a lower degree of optimization but higher variability benefit from reducing the mutation rate to adapt rapidly. These findings show a good agreement with the behaviour exhibited by actual organisms that replicate their genomes under broadly different mutation rates.

  12. Isoenzymatic variability in tropical maize populations under reciprocal recurrent selection

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    Pinto Luciana Rossini

    2003-01-01

    Full Text Available Maize (Zea mays L. is one of the crops in which the genetic variability has been extensively studied at isoenzymatic loci. The genetic variability of the maize populations BR-105 and BR-106, and the synthetics IG-3 and IG-4, obtained after one cycle of a high-intensity reciprocal recurrent selection (RRS, was investigated at seven isoenzymatic loci. A total of twenty alleles were identified, and most of the private alleles were found in the BR-106 population. One cycle of reciprocal recurrent selection (RRS caused reductions of 12% in the number of alleles in both populations. Changes in allele frequencies were also observed between populations and synthetics, mainly for the Est 2 locus. Populations presented similar values for the number of alleles per locus, percentage of polymorphic loci, and observed and expected heterozygosities. A decrease of the genetic variation values was observed for the synthetics as a consequence of genetic drift effects and reduction of the effective population sizes. The distribution of the genetic diversity within and between populations revealed that most of the diversity was maintained within them, i.e. BR-105 x BR-106 (G ST = 3.5% and IG-3 x IG-4 (G ST = 4.0%. The genetic distances between populations and synthetics increased approximately 21%. An increase in the genetic divergence between the populations occurred without limiting new selection procedures.

  13. Cytogenetic variability in pinus sylvestris L. populations experiencing anthropogenic influence

    International Nuclear Information System (INIS)

    Oudalova, A.; Geras'kin, S.; Vasiliev, D.; Dikarev, V.

    2004-01-01

    Techno-genic pollution has become one of the most significant ecological factors determining biosphere existence and development. An analysis of genetic consequences of the radiation accidents in the South Urals and Chernobyl has shown that mutation and recombination processes are considerably accelerated in plant and animal's populations experiencing techno-genic influence. This implies that there are complicated adaptation processes leading to changes in genetic structure of populations and increasing genetic load. Pinus sylvestris L. populations growing at the territory of the 'radon' Leningrad regional radioactive waste reprocessing enterprise and Sosnovy Bor town were monitored 6 years (1997-2002) by a set of cyto-genetical and morphological tests. Cytogenetic damage levels within intercalary meristem of needle as well as in root meristem of seedlings were found to significantly exceed corresponding controls. A higher radioresistance of the Scots pine seeds analyzed was demonstrated with an acute γ-radiation that also revealed a selection process directed at an enhancement of repair efficiency and resulting in a shift of mean values of radioresistance in populations towards higher values. An enlargement of variance of studied cytogenetic parameters was found in the populations experiencing techno-genic influence. This indicates, with an account of phenomenon of the enhanced radioresistance, that there are processes of cyto-genetical adaptation in the investigated regions. An analysis of the structure of ecological-genetical variability was carried out with the purpose of separating two components in the inter-population variability - the first is engaged to the genetically determined variability of biological characteristics intrinsic for this species, and the second is responsible for the variability originating from anthropogenic contamination of the natural habitat. Changes of these two types of variability were studied in dependence on time and techno

  14. Cytogenetic variability in pinus sylvestris L. populations experiencing anthropogenic influence

    Energy Technology Data Exchange (ETDEWEB)

    Oudalova, A.; Geras' kin, S.; Vasiliev, D.; Dikarev, V. [Russian Institute of Agricultural Radiology and Agroecology, Obninsk (Russian Federation)

    2004-07-01

    Techno-genic pollution has become one of the most significant ecological factors determining biosphere existence and development. An analysis of genetic consequences of the radiation accidents in the South Urals and Chernobyl has shown that mutation and recombination processes are considerably accelerated in plant and animal's populations experiencing techno-genic influence. This implies that there are complicated adaptation processes leading to changes in genetic structure of populations and increasing genetic load. Pinus sylvestris L. populations growing at the territory of the 'radon' Leningrad regional radioactive waste reprocessing enterprise and Sosnovy Bor town were monitored 6 years (1997-2002) by a set of cyto-genetical and morphological tests. Cytogenetic damage levels within intercalary meristem of needle as well as in root meristem of seedlings were found to significantly exceed corresponding controls. A higher radioresistance of the Scots pine seeds analyzed was demonstrated with an acute {gamma}-radiation that also revealed a selection process directed at an enhancement of repair efficiency and resulting in a shift of mean values of radioresistance in populations towards higher values. An enlargement of variance of studied cytogenetic parameters was found in the populations experiencing techno-genic influence. This indicates, with an account of phenomenon of the enhanced radioresistance, that there are processes of cyto-genetical adaptation in the investigated regions. An analysis of the structure of ecological-genetical variability was carried out with the purpose of separating two components in the inter-population variability - the first is engaged to the genetically determined variability of biological characteristics intrinsic for this species, and the second is responsible for the variability originating from anthropogenic contamination of the natural habitat. Changes of these two types of variability were studied in dependence on

  15. Seasonal Variability of Phytoplankton Population in the Brahmani ...

    African Journals Online (AJOL)

    Seasonal Variability of Phytoplankton Population in the Brahmani Estuary of Orissa, India. S Palleyi, RN Kar, CR Panda. Abstract. The dynamic relationship of water physico-chemical characteristics with phytoplankton has long been of great interest in both experimental ecology and environmental management. This study ...

  16. Identifying populations sensitive to environmental chemicals by simulating toxicokinetic variability.

    Science.gov (United States)

    Ring, Caroline L; Pearce, Robert G; Setzer, R Woodrow; Wetmore, Barbara A; Wambaugh, John F

    2017-09-01

    The thousands of chemicals present in the environment (USGAO, 2013) must be triaged to identify priority chemicals for human health risk research. Most chemicals have little of the toxicokinetic (TK) data that are necessary for relating exposures to tissue concentrations that are believed to be toxic. Ongoing efforts have collected limited, in vitro TK data for a few hundred chemicals. These data have been combined with biomonitoring data to estimate an approximate margin between potential hazard and exposure. The most "at risk" 95th percentile of adults have been identified from simulated populations that are generated either using standard "average" adult human parameters or very specific cohorts such as Northern Europeans. To better reflect the modern U.S. population, we developed a population simulation using physiologies based on distributions of demographic and anthropometric quantities from the most recent U.S. Centers for Disease Control and Prevention National Health and Nutrition Examination Survey (NHANES) data. This allowed incorporation of inter-individual variability, including variability across relevant demographic subgroups. Variability was analyzed with a Monte Carlo approach that accounted for the correlation structure in physiological parameters. To identify portions of the U.S. population that are more at risk for specific chemicals, physiologic variability was incorporated within an open-source high-throughput (HT) TK modeling framework. We prioritized 50 chemicals based on estimates of both potential hazard and exposure. Potential hazard was estimated from in vitro HT screening assays (i.e., the Tox21 and ToxCast programs). Bioactive in vitro concentrations were extrapolated to doses that produce equivalent concentrations in body tissues using a reverse dosimetry approach in which generic TK models are parameterized with: 1) chemical-specific parameters derived from in vitro measurements and predicted from chemical structure; and 2) with

  17. Population growth is a variable open to change

    Science.gov (United States)

    Potts, M.

    2016-12-01

    The absolute number of people and the rate of population growth have an impact on climate mitigation, adaptation and possible conflict. Half the pregnancies in the US are unintended. Robust quantitative evidence from California demonstrates that improving access to family planning is the single most cost-effective way of mitigating our carbon footprint. Globally, there are 80 million unintended pregnancies annually. Many non-evidence barriers deprive women of the information and means required to separate sex from childbearing. Between 1960 and 1990, meeting the need for family planning led to a rapid fall in family size in much of Asia. Since 1990, funding for family planning has collapsed and fertility decline has stalled. The UN projects that by 2100 global population will increase by 3.8 billion (equal to world population in 1975). 80% of this growth will be in Africa. Studies project that climate change will undermine crop yields in parts of Africa, especially the Sahel. A high ratio of young males to the rest of the population is a risk factor in conflict. Today, only 1% of overseas assistance is allocated to family planning. Based on analysis of the past, doubling that investment would accelerate fertility decline, facilitating climate mitigation and adaptation, and possibly reducing conflict. Population and family planning were pushed off the international agenda by unacceptably and tragic episodes of coercion in China and India. However, there is compelling data that when voluntary family planning is widely available then family size can fall rapidly, as occurred in the Islamic Republic of Iran, where fertility fell more rapidly than in any other country in history. Family planning is listening to what women want not telling people want to do. Population growth is a variable open to change in a human rights framework. Population and family planning are variables relevant to the scientific agenda of the AGU.

  18. Exploring the Variability of the Fermi LAT Blazar Population

    Science.gov (United States)

    Macomb, Daryl J.; Shrader, C. R.

    2014-01-01

    The flux variability of the approximately 2000 point sources cataloged by the Fermi Gamma-Ray Space Telescope provide important clues to population characteristics. This is particularly true of the more than 1100 source that are likely AGN. By characterizing the intrinsic flux variability and distinguishing this variability from flaring behavior, we can better address questions of flare amplitudes, durations, recurrence times, and temporal profiles. A better understanding of the responsible physical environments, such as the scale and location of jet structures responsible for the high-energy emission, may emerge from such studies. Assessing these characteristics as a function of blazar sub-class is a further goal in order to address questions about the fundamentals of blazar AGN physics. Here we report on progress made in categorizing blazar flare behavior, and correlate these behaviors with blazar sub-type and other source parameters.

  19. Phenotypic variability in a population of globe artichoke

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    Angélica Reolon da Costa

    2014-11-01

    Full Text Available The existence of variability is a prerequisite for genetic improvement in plants. Globe artichoke is a high nutritious vegetable with medical value, representing a profitable alternative for rural producers. This research was conducted with the aim of evaluating the phenotypic variability in a commercial cultivar of artichoke (Cynara cardunculus var. scolymus L established from seeds. Field plants were assessed when primary head reached commercial stage. An amount of 21 quantitative and 5 multicategoric characters were assessed. The quantitative data were submitted to multivariate analysis. For quantitative characters the distance between individuals varied from 3.0 to 50.9, revealing high intrapopulation variability. The greater relative contribution characters for genetic divergence were the primary head fresh mass (79.88% and bottom fresh mass (8.43%. This indicates the possibility of plant selection for head quality in this population. The clustering analysis through UPGMA method, based on quantitative characters, allowed the formation of five groups. For multicategoric traits, the similarity among individuals varied from 1.22% to 100%. Within the existing population variability, it was possible to select plants with superior quantitative traits desirable for in natura consumption, as primary head fresh weight and length, bottom fresh mass, bract basis length and width, as well as non-quantitative traits as round head shape, absence of thorn and presence of violet color in the head.

  20. Estimates of genetic variability in mutated population of triticum aestivum

    International Nuclear Information System (INIS)

    Larik, A.S.; Siddiqui, K.A.; Soomoro, A.H.

    1980-01-01

    M 2 populations of four cultivars of Mexican origin (Mexipak-65, Nayab, Pak-70 and 6134 x C-271) and two locally bred cultivars (H-68 and C-591) of bread wheat, triticum aestivum (2n = 6x = AA BB DD) derived from six irradiation treatments (gamma rays 60sub(Co); 10, 15 and 20 kR and fast neutrons; 300, 600 and 900 RADS) were critically examined for spike length, spikelets per spike, grains per spike and grain yield. Genotypes varied significantly (p>=0.01) for all the characters. Irradiation treatment were instrumental in creating significant variability for all the characters, indicating that varieties did not perform uniformly across different gamma rays as well as fast neutron treatments. In the M 2 generation there was a considerable increase in variance for all the four metrical traits. Comparisons were made between controls and treated populations. Mutagenic treatments shifted the mean values mostly towards the negative direction, but the shift was not unidirectional nor equally effective for all the characters. The differences in mean values and the nature of variability observed in M 2 indicated a possible preference of selection M 3 generation. In general, estimates of genetic variability and heritability (b.s) increased with increasing doses of gamma rays and fast neutrons. Genetic advance also exhibited similar trend. The observed variability can be utilized in the evolution of new varieties. (authors)

  1. CYP2D6 variability in populations from Venezuela.

    Science.gov (United States)

    Moreno, Nancy; Flores-Angulo, Carlos; Villegas, Cecilia; Mora, Yuselin

    2016-12-01

    CYP2D6 is an important cytochrome P450 enzyme that plays an important role in the metabolism of about 25% of currently prescribed drugs. The presence of polymorphisms in the CYP2D6 gene may modulate enzyme level and activity, thereby affecting individual responses to pharmacological treatments. The most prevalent diseases in the admixed population from Venezuela are cardiovascular and cancer, whereas viral, bacterial and parasitic diseases, particularly malaria, are prevalent in Amerindian populations; in the treatment of these diseases, several drugs that are metabolized by CYP2D6 are used. In this work, we reviewed the data on CYP2D6 variability and predicted metabolizer phenotypes, in healthy volunteers of two admixed and five Amerindian populations from Venezuela. The Venezuelan population is very heterogeneous as a result of the genetic admixture of three major ethnical components: Europeans, Africans and Amerindians. There are noticeable inter-regional and inter-population differences in the process of mixing of this population. Hitherto, there are few published studies in Venezuela on CYP2D6; therefore, it is necessary to increase research in this regard, in particular to develop studies with a larger sample size. There is a considerable amount of work remaining before CYP2D6 is integrated into clinical practice in Venezuela.

  2. Variability of Caltha palustris L. populations in garden culture

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    Krystyna Falińska

    2014-01-01

    Full Text Available On the basis of studies performed in the experimental garden the character of the variability of Caltha palustris L. populations is described. Individuals were bred under uniform conditions from diaspores of meadow, springwood, flood-plain forest and alder forest populations. The results obtained allow to evaluate the hypothesis concerning the ecological preference of cytotypes (S m i t 1967, 1968 and the somewhat different ecological requirements of two subspecies: C. palustris ssp. palustris and C. palustris ssp. cornuta. It was found that each population includes individuals with different cytotypes. The situation is similar as far as subspecies are concerned, distinguished on the basis of fruit morphology (Fig. 1. It should be stressed, however, that, investigations of many years duration raised serious doubts as to the diagnostic value of fruit morphology (Figs. 2, 3. On the basis of the preserved differences between the populations in shoot habitus, reproduction and phenology in garden culture, a springwood and an alder forest ecotype were distinguished. Meadow and flood-plain populations exhibited a transitional character with certain similarities both to the alder forest and to the springwood populations.

  3. Selection for altruism through random drift in variable size populations

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    Houchmandzadeh Bahram

    2012-05-01

    Full Text Available Abstract Background Altruistic behavior is defined as helping others at a cost to oneself and a lowered fitness. The lower fitness implies that altruists should be selected against, which is in contradiction with their widespread presence is nature. Present models of selection for altruism (kin or multilevel show that altruistic behaviors can have ‘hidden’ advantages if the ‘common good’ produced by altruists is restricted to some related or unrelated groups. These models are mostly deterministic, or assume a frequency dependent fitness. Results Evolutionary dynamics is a competition between deterministic selection pressure and stochastic events due to random sampling from one generation to the next. We show here that an altruistic allele extending the carrying capacity of the habitat can win by increasing the random drift of “selfish” alleles. In other terms, the fixation probability of altruistic genes can be higher than those of a selfish ones, even though altruists have a smaller fitness. Moreover when populations are geographically structured, the altruists advantage can be highly amplified and the fixation probability of selfish genes can tend toward zero. The above results are obtained both by numerical and analytical calculations. Analytical results are obtained in the limit of large populations. Conclusions The theory we present does not involve kin or multilevel selection, but is based on the existence of random drift in variable size populations. The model is a generalization of the original Fisher-Wright and Moran models where the carrying capacity depends on the number of altruists.

  4. An application of the variable-r method to subpopulation growth rates in a 19th century agricultural population

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    Corey Sparks

    2009-07-01

    Full Text Available This paper presents an analysis of the differential growth rates of the farming and non-farming segments of a rural Scottish community during the 19th and early 20th centuries using the variable-r method allowing for net migration. Using this method, I find that the farming population of Orkney, Scotland, showed less variability in their reproduction and growth rates than the non-farming population during a period of net population decline. I conclude by suggesting that the variable-r method can be used in general cases where the relative growth of subpopulations or subpopulation reproduction is of interest.

  5. Chaos. Possible underpinnings for quantum mechanics?

    International Nuclear Information System (INIS)

    McHarris, Wm.C.

    2004-01-01

    Alternative, parallel explanations for a number of counter-intuitive concepts connected with the foundations of quantum mechanics can be constructed in terms of nonlinear dynamics. These include ideas as diverse as the statistical exponential decay law and spontaneous symmetry breaking to decoherence itself and the inference from violations of Bell's inequality that local reality is ruled out in hidden variable extensions of quantum mechanics. Such alternative explanations must not be taken as demonstrations of nonlinear underpinnings for quantum mechanics, but they do raise the possibility of their existence. In this article I delve a bit into ideas connected with the exponential decay law and with Bell's inequality as demonstrations. Then an investigation of the Klein-Gordon equation shows that it should not come as a complete surprise that quantum mechanics just might contain fundamental nonlinearities. (author)

  6. Ecological mechanisms underpinning climate adaptation services.

    Science.gov (United States)

    Lavorel, Sandra; Colloff, Matthew J; McIntyre, Sue; Doherty, Michael D; Murphy, Helen T; Metcalfe, Daniel J; Dunlop, Michael; Williams, Richard J; Wise, Russell M; Williams, Kristen J

    2015-01-01

    Ecosystem services are typically valued for their immediate material or cultural benefits to human wellbeing, supported by regulating and supporting services. Under climate change, with more frequent stresses and novel shocks, 'climate adaptation services', are defined as the benefits to people from increased social ability to respond to change, provided by the capability of ecosystems to moderate and adapt to climate change and variability. They broaden the ecosystem services framework to assist decision makers in planning for an uncertain future with new choices and options. We present a generic framework for operationalising the adaptation services concept. Four steps guide the identification of intrinsic ecological mechanisms that facilitate the maintenance and emergence of ecosystem services during periods of change, and so materialise as adaptation services. We applied this framework for four contrasted Australian ecosystems. Comparative analyses enabled by the operational framework suggest that adaptation services that emerge during trajectories of ecological change are supported by common mechanisms: vegetation structural diversity, the role of keystone species or functional groups, response diversity and landscape connectivity, which underpin the persistence of function and the reassembly of ecological communities under severe climate change and variability. Such understanding should guide ecosystem management towards adaptation planning. © 2014 John Wiley & Sons Ltd.

  7. Wireless-accessible sensor populations for monitoring biological variables

    NARCIS (Netherlands)

    Mazzu, Marco; Scalvini, Simonetta; Giordano, A.; Frumento, E.; Wells, Hannah; Lokhorst, C.; Glisenti, Fulvio

    2008-01-01

    The current health-care infrastructure is generally considered to be inadequate to meet the needs of an increasingly older population. We have investigated the feasibility of a passive in-home monitoring system based on wireless accessible sensor populations (WASP). In an EU-funded project we have

  8. Variability and Character Association in F2 Segregating Population ...

    African Journals Online (AJOL)

    Michael Horsfall

    Department of Genetics and Plant Breeding, 1Department of Horticulture. Bangabandhu Sheikh Mujibur Rahman Agricultural University. Gazipur 1706, Bangladesh. ABSTRACT: The F2 segregating generations of exotic tomato hybrids were studied to measure variability, character association and path coefficient analysis.

  9. Investigating Factorial Invariance of Latent Variables Across Populations When Manifest Variables Are Missing Completely.

    Science.gov (United States)

    Widaman, Keith F; Grimm, Kevin J; Early, Dawnté R; Robins, Richard W; Conger, Rand D

    2013-07-01

    Difficulties arise in multiple-group evaluations of factorial invariance if particular manifest variables are missing completely in certain groups. Ad hoc analytic alternatives can be used in such situations (e.g., deleting manifest variables), but some common approaches, such as multiple imputation, are not viable. At least 3 solutions to this problem are viable: analyzing differing sets of variables across groups, using pattern mixture approaches, and a new method using random number generation. The latter solution, proposed in this article, is to generate pseudo-random normal deviates for all observations for manifest variables that are missing completely in a given sample and then to specify multiple-group models in a way that respects the random nature of these values. An empirical example is presented in detail comparing the 3 approaches. The proposed solution can enable quantitative comparisons at the latent variable level between groups using programs that require the same number of manifest variables in each group.

  10. Convergent molecular defects underpin diverse neurodegenerative diseases.

    Science.gov (United States)

    Tofaris, George K; Buckley, Noel J

    2018-02-19

    In our ageing population, neurodegenerative disorders carry an enormous personal, societal and economic burden. Although neurodegenerative diseases are often thought of as clinicopathological entities, increasing evidence suggests a considerable overlap in the molecular underpinnings of their pathogenesis. Such overlapping biological processes include the handling of misfolded proteins, defective organelle trafficking, RNA processing, synaptic health and neuroinflammation. Collectively but in different proportions, these biological processes in neurons or non-neuronal cells lead to regionally distinct patterns of neuronal vulnerability and progression of pathology that could explain the disease symptomology. With the advent of patient-derived cellular models and novel genetic manipulation tools, we are now able to interrogate this commonality despite the cellular complexity of the brain in order to develop novel therapeutic strategies to prevent or arrest neurodegeneration. Here, we describe broadly these concepts and their relevance across neurodegenerative diseases. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  11. Some Social Variables In Domestic Violence In A Nigerian Population

    African Journals Online (AJOL)

    Background:Domestic violence is any intentional abuse of a family member mostly women by a partner which causes pain or injury. It is a growing phenomenon and is affected by several social variables. In pregnancy, domestic violence causes adverse pregnancy outcomes and other reproductive health consequences to ...

  12. Genetic variability in the population of the endemic bee Anthophora ...

    African Journals Online (AJOL)

    The genetic diversity and spatial genetic population structure of the solitary bee Anthophora pauperata Walker 1871, a species endemic to St Katherine Protectorate, were studied by RAPD markers in seven wadis in the St Katherine Protectorate, South Sinai, Egypt. High levels of genetic diversity were found, mostly within ...

  13. Genetic variability and structure of an isolated population of ...

    Indian Academy of Sciences (India)

    Rosa-Laura Heredia-Bobadilla

    2017-11-15

    Nov 15, 2017 ... Journal of Genetics, Vol. 96, No. 6, December 2017 ... or international status of protection. The mole ... populations by a matrix of agriculture and urbanization, can be considered ...... BioScience 38, 471–479. Lemos-Espinal ...

  14. Bayesian Hierarchical Structure for Quantifying Population Variability to Inform Probabilistic Health Risk Assessments.

    Science.gov (United States)

    Shao, Kan; Allen, Bruce C; Wheeler, Matthew W

    2017-10-01

    Human variability is a very important factor considered in human health risk assessment for protecting sensitive populations from chemical exposure. Traditionally, to account for this variability, an interhuman uncertainty factor is applied to lower the exposure limit. However, using a fixed uncertainty factor rather than probabilistically accounting for human variability can hardly support probabilistic risk assessment advocated by a number of researchers; new methods are needed to probabilistically quantify human population variability. We propose a Bayesian hierarchical model to quantify variability among different populations. This approach jointly characterizes the distribution of risk at background exposure and the sensitivity of response to exposure, which are commonly represented by model parameters. We demonstrate, through both an application to real data and a simulation study, that using the proposed hierarchical structure adequately characterizes variability across different populations. © 2016 Society for Risk Analysis.

  15. Global population variability in Qiagen Investigator HDplex STRs.

    Science.gov (United States)

    Phillips, C; Fernandez-Formoso, L; Gelabert-Besada, M; García-Magariños, M; Amigo, J; Carracedo, A; Lareu, M V

    2014-01-01

    Supplementary short tandem repeats (STRs) can be added to forensic analyses if the 15-24 core STRs in routine use fail to give sufficient discrimination power in complex identification or relationship testing scenarios. In this study, 10 of 12 supplementary STRs in the Qiagen Investigator HDplex kit (SE33, D2S1360, D3S1744, D4S2366, D5S2500, D6S474, D7S1517, D8S1132, D10S2325, D21S2055) were genotyped in 941 individuals from the 51 populations of the CEPH Human Genome Diversity Panel (HGDP-CEPH). The other two components of the 12-STR HDplex kit are established STRs D12S391 and D18S51 that we previously genotyped for the HGDP-CEPH panel. We describe the rare alleles identified and outline allele frequency distributions in the seven population groups of the HGDP-CEPH panel. The HDplex STRs novel to forensic application were found to be both highly informative and comparable in their power across all populations studied: at least six of the nine loci showing above average forensic discrimination power in each population group. In some rare instances certain low frequency alleles in D2S1360 were found to overlap in mobility with the neighbouring allele size ranges of D12S391, as well as those of D7S1517 with neighbouring D3S1744 and D10S2325 with neighbouring SE33. Lastly, since expanded five-dye multiplex kits of 20 STRs (Promega Powerplex 21) and 22 STRs (Promega Powerplex Fusion) have recently been introduced, we assess through simulations the increased power to analyse pairwise relationships in deficient pedigrees that can be expected from an optimum kit pair: combining HDplex with either of the above sets to provide 30 or 32 unique STRs and just two overlapping loci. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  16. Bayesian Population Physiologically-Based Pharmacokinetic (PBPK Approach for a Physiologically Realistic Characterization of Interindividual Variability in Clinically Relevant Populations.

    Directory of Open Access Journals (Sweden)

    Markus Krauss

    Full Text Available Interindividual variability in anatomical and physiological properties results in significant differences in drug pharmacokinetics. The consideration of such pharmacokinetic variability supports optimal drug efficacy and safety for each single individual, e.g. by identification of individual-specific dosings. One clear objective in clinical drug development is therefore a thorough characterization of the physiological sources of interindividual variability. In this work, we present a Bayesian population physiologically-based pharmacokinetic (PBPK approach for the mechanistically and physiologically realistic identification of interindividual variability. The consideration of a generic and highly detailed mechanistic PBPK model structure enables the integration of large amounts of prior physiological knowledge, which is then updated with new experimental data in a Bayesian framework. A covariate model integrates known relationships of physiological parameters to age, gender and body height. We further provide a framework for estimation of the a posteriori parameter dependency structure at the population level. The approach is demonstrated considering a cohort of healthy individuals and theophylline as an application example. The variability and co-variability of physiological parameters are specified within the population; respectively. Significant correlations are identified between population parameters and are applied for individual- and population-specific visual predictive checks of the pharmacokinetic behavior, which leads to improved results compared to present population approaches. In the future, the integration of a generic PBPK model into an hierarchical approach allows for extrapolations to other populations or drugs, while the Bayesian paradigm allows for an iterative application of the approach and thereby a continuous updating of physiological knowledge with new data. This will facilitate decision making e.g. from preclinical to

  17. Population structure and genetic variability of mainland and insular populations of the Neotropical water rat, Nectomys squamipes (Rodentia, Sigmodontinae

    Directory of Open Access Journals (Sweden)

    Francisca C. Almeida

    2005-12-01

    Full Text Available Seven microsatellite loci were used to investigate the genetic variability and structure of six mainland and two island populations of the Neotropical water rat Nectomys squamipes, a South American semi-aquatic rodent species with a wide distribution. High levels of variability were found within mainland populations while island populations were less variable but the more differentiated in respect to allele number and frequency. The time of biological divergence between mainland and island populations coincided with geological data. A significant geographic structure was found in mainland populations (theta = 0.099; rho = 0.086 although the degree of differentiation was relatively low in respect to the distance between surveyed localities (24 to 740 km. Genetic and geographic distances were not positively correlated as previously found with random amplified polymorphic DNA (RAPD markers. Significant but low genetic differentiation in the mainland and lack of isolation by distance can be explained by large population size and/or recent population expansion. Additionally, the agreement between the age of geologic events (sea level fluctuations and divergence times for insular populations points to a good reference for molecular clock calibration to associate recent environmental changes and the distribution pattern of small mammals in the Brazilian Atlantic Forest.

  18. Assessment of genetic variability in somaclonal population of sugarcane

    International Nuclear Information System (INIS)

    Seema, N.; Raza, S.; Yasmeen, S.; Bibi, S.; Nizamani, G.S.

    2014-01-01

    In the present study plant tissue culture technique was used to create the genetic variability in three sugarcane clones NIA98, BL4 and AEC82-1026. Callus induced in these clones in media containing MS + 2, 4 D (2mg 1it-1) and Dicamba (1mg1it-1). The embryogenic calli then regenerated in media containing MS basal media + Kinetin (2mg1it-1) + IBA (2mg1it-1) + IAA (2mglit-1). After shooting and rooting, plants were exposed to green house and acclimatization of the somaclones in the field condition. RAPD markers were used to evaluate the genetic variation at DNA level between parents and somaclones of NIA98, BL4 and AEC82-1026 developed through callus culture. Fourteen RAPD primer chosen randomly were used to amplify DNA from plant material to assess the genetic variation between parents and regenerated somaclones. The highest similarity was obtained between BL4 parent and BL4 somaclone (96%). While minimum similarity found between NIA-98 parent and AEC82-1026 somaclone (69%). In this study, we used RAPD to investigate the somaclonal variation in sugarcane clones derived from callus cultures. (author)

  19. Genetic variation in variability: phenotypic variability of fledging weight and its evolution in a songbird population

    NARCIS (Netherlands)

    Mulder, H.A.; Gienapp, P; Visser, ME

    2016-01-01

    Variation in traits is essential for natural selection to operate and genetic and environmental effects can contribute to this phenotypic variation. From domesticated populations, we know that families can differ in their level of within-family variance, which leads to the intriguing situation that

  20. Exploiting Fast-Variables to Understand Population Dynamics and Evolution

    Science.gov (United States)

    Constable, George W. A.; McKane, Alan J.

    2017-11-01

    We describe a continuous-time modelling framework for biological population dynamics that accounts for demographic noise. In the spirit of the methodology used by statistical physicists, transitions between the states of the system are caused by individual events while the dynamics are described in terms of the time-evolution of a probability density function. In general, the application of the diffusion approximation still leaves a description that is quite complex. However, in many biological applications one or more of the processes happen slowly relative to the system's other processes, and the dynamics can be approximated as occurring within a slow low-dimensional subspace. We review these time-scale separation arguments and analyse the more simple stochastic dynamics that result in a number of cases. We stress that it is important to retain the demographic noise derived in this way, and emphasise this point by showing that it can alter the direction of selection compared to the prediction made from an analysis of the corresponding deterministic model.

  1. Intraregional and inter-regional variability of herbicide sensitivity in common arable weed populations

    DEFF Research Database (Denmark)

    de Mol, Friederike; Gerowitt, Bärbel; Kaczmarek, Sylwia

    2015-01-01

    The question on intraregional versus inter-regional variability in herbicide sensitivity for weed populations is of major importance, both in extrapolation of model parameters and in herbicide zonal approval procedures. We hypothesised that inter-regional variability in herbicide sensitivity for ...

  2. Population dynamics under increasing environmental variability: implications of climate change for ecological network design criteria

    NARCIS (Netherlands)

    Verboom, J.; Schippers, P.; Cormont, A.; Sterk, M.; Vos, C.C.; Opdam, P.F.M.

    2010-01-01

    There is growing evidence that climate change causes an increase in variation in conditions for plant and animal populations. This increase in variation, e.g. amplified inter-annual variability in temperature and rainfall has population dynamical consequences because it raises the variation in vital

  3. Estimation of Finite Population Ratio When Other Auxiliary Variables are Available in the Study

    Directory of Open Access Journals (Sweden)

    Jehad Al-Jararha

    2014-12-01

    Full Text Available The estimation of the population total $t_y,$ by using one or moreauxiliary variables, and the population ratio $\\theta_{xy}=t_y/t_x,$$t_x$ is the population total for the auxiliary variable $X$, for afinite population are heavily discussed in the literature. In thispaper, the idea of estimation the finite population ratio$\\theta_{xy}$ is extended to use the availability of auxiliaryvariable $Z$ in the study, such auxiliary variable  is not used inthe definition of the population ratio. This idea may be  supported by the fact that the variable $Z$  is highly correlated with the interest variable $Y$ than the correlation between the variables $X$ and $Y.$ The availability of such auxiliary variable can be used to improve the precision of the estimation of the population ratio.  To our knowledge, this idea is not discussed in the literature.  The bias, variance and the mean squares error  are given for our approach. Simulation from real data set,  the empirical relative bias and  the empirical relative mean squares error are computed for our approach and different estimators proposed in the literature  for estimating the population ratio $\\theta_{xy}.$ Analytically and the simulation results show that, by suitable choices, our approach gives negligible bias and has less mean squares error.  

  4. Five decades on: Use of historical weaning size data reveals that a decrease in maternal foraging success underpins the long-term decline in population of southern elephant seals (Mirounga leonina.

    Directory of Open Access Journals (Sweden)

    Ella Clausius

    Full Text Available The population of Southern elephant seals (Mirounga leonina at Macquarie Island has declined since the 1960s, and is thought to be due to changing oceanic conditions leading to reductions in the foraging success of Macquarie Island breeding females. To test this hypothesis, we used a 55-year-old data set on weaning size of southern elephant seals to quantify a decrease in weaning size from a period of population stability in 1950s to its present state of on-going decline. Being capital breeders, the size of elephant seal pups at weaning is a direct consequence of maternal foraging success in the preceding year. During the 1940-1950s, the mean of female pups at weaning was similar between the Heard and Macquarie Island populations, while the snout-tail-length length of male weaners from Heard Island were longer than their conspecifics at Macquarie Island. Additionally, the snout-tail-length of pups at weaning decreased by 3cm between the 1950s and 1990s in the Macquarie Island population, concurrent with the observed population decline. Given the importance of weaning size in determining first-year survival and recruitment rates, the decline in the size at weaning suggests that the decline in the Macquarie Island population has, to some extent, been driven by reduced maternal foraging success, consequent declines in the size of pups at weaning, leading to reduced first-year survival rates and recruitment of breeding females into the population 3 to 4 years later.

  5. The scaling of population persistence with carrying capacity does not asymptote in populations of a fish experiencing extreme climate variability.

    Science.gov (United States)

    White, Richard S A; Wintle, Brendan A; McHugh, Peter A; Booker, Douglas J; McIntosh, Angus R

    2017-06-14

    Despite growing concerns regarding increasing frequency of extreme climate events and declining population sizes, the influence of environmental stochasticity on the relationship between population carrying capacity and time-to-extinction has received little empirical attention. While time-to-extinction increases exponentially with carrying capacity in constant environments, theoretical models suggest increasing environmental stochasticity causes asymptotic scaling, thus making minimum viable carrying capacity vastly uncertain in variable environments. Using empirical estimates of environmental stochasticity in fish metapopulations, we showed that increasing environmental stochasticity resulting from extreme droughts was insufficient to create asymptotic scaling of time-to-extinction with carrying capacity in local populations as predicted by theory. Local time-to-extinction increased with carrying capacity due to declining sensitivity to demographic stochasticity, and the slope of this relationship declined significantly as environmental stochasticity increased. However, recent 1 in 25 yr extreme droughts were insufficient to extirpate populations with large carrying capacity. Consequently, large populations may be more resilient to environmental stochasticity than previously thought. The lack of carrying capacity-related asymptotes in persistence under extreme climate variability reveals how small populations affected by habitat loss or overharvesting, may be disproportionately threatened by increases in extreme climate events with global warming. © 2017 The Author(s).

  6. Life-history strategies associated with local population variability confer regional stability.

    Science.gov (United States)

    Pribil, Stanislav; Houlahan, Jeff E

    2003-07-07

    A widely held ecological tenet is that, at the local scale, populations of K-selected species (i.e. low fecundity, long lifespan and large body size) will be less variable than populations of r-selected species (i.e. high fecundity, short lifespan and small body size). We examined the relationship between long-term population trends and life-history attributes for 185 bird species in the Czech Republic and found that, at regional spatial scales and over moderate temporal scales (100-120 years), K-selected bird species were more likely to show both large increases and decreases in population size than r-selected species. We conclude that life-history attributes commonly associated with variable populations at the local scale, confer stability at the regional scale.

  7. Revisiting the role of individual variability in population persistence and stability.

    Directory of Open Access Journals (Sweden)

    Andrew Morozov

    Full Text Available Populations often exhibit a pronounced degree of individual variability and this can be important when constructing ecological models. In this paper, we revisit the role of inter-individual variability in population persistence and stability under predation pressure. As a case study, we consider interactions between a structured population of zooplankton grazers and their predators. Unlike previous structured population models, which only consider variability of individuals according to the age or body size, we focus on physiological and behavioural structuring. We first experimentally demonstrate a high degree of variation of individual consumption rates in three dominant species of herbivorous copepods (Calanus finmarchicus, Calanus glacialis, Calanus euxinus and show that this disparity implies a pronounced variation in the consumption capacities of individuals. Then we construct a parsimonious predator-prey model which takes into account the intra-population variability of prey individuals according to behavioural traits: effectively, each organism has a 'personality' of its own. Our modelling results show that structuring of prey according to their growth rate and vulnerability to predation can dampen predator-prey cycles and enhance persistence of a species, even if the resource stock for prey is unlimited. The main mechanism of efficient top-down regulation is shown to work by letting the prey population become dominated by less vulnerable individuals when predator densities are high, while the trait distribution recovers when the predator densities are low.

  8. High population variability and source-sink dynamics in a solitary bee species.

    Science.gov (United States)

    Franzén, Markus; Nilsson, Sven G

    2013-06-01

    Although solitary bees are considered to play key roles in ecosystem functions, surprisingly few studies have explored their population dynamics. We investigated the population dynamics of a rare, declining, solitary bee (Andrena humilis) in a landscape of 80 km2 in southern Sweden from 2003 to 2011. Only one population was persistent throughout all years studied; most likely this population supplied the surrounding landscape with 11 smaller, temporary local populations. Despite stable pollen availability, the size of the persistent population fluctuated dramatically in a two-year cycle over the nine years, with 490-1230 nests in odd-numbered years and 21-48 nests in even-numbered years. These fluctuations were not significantly related to climatic variables or pollen availability. Nineteen colonization and 14 extinction events were recorded. Occupancy decreased with distance from the persistent population and increased with increasing resource (pollen) availability. There were significant positive correlations between the size of the persistent population and patch occupancy and colonization. Colonizations were generally more common in patches closer to the persistent population, whereas extinctions were independent of distance from the persistent population. Our results highlight the complex population dynamics that exist for this solitary bee species, which could be due to source-sink dynamics, a prolonged diapause, or can represent a bet-hedging strategy to avoid natural enemies and survive in small habitat patches. If large fluctuations in solitary bee populations prove to be widespread, it will have important implications for interpreting ecological relationships, bee conservation, and pollination.

  9. Intraspecific variability of camu-camu fruit in native populations of northern Amazonia

    Directory of Open Access Journals (Sweden)

    Edvan Alves Chagas

    2015-12-01

    Full Text Available Similarly to most breeding programs of native species, camu-camu (Myrciaria dubia (Kunt McVaugh improvement is also restricted, due to the scarcity of research results. In this situation, the prospection, collection and conservation of germplasm in genebanks ensure successful selection and breeding studies of the species. In this sense, the purpose of this study was the intraspecific characterization of the biometric variability in fruits of native camu-camu populations of the State of Roraima, in the northern Amazon region. Of 16 populations, 247 sub-samples were evaluated. Analyses were performed with the multivariate technique of principal components and hierarchical clustering, to determine the variables with highest intraspecific variability for the studied traits. The populations found in the lower Rio Branco region performed best for the studied traits, indicating the great potential of the region as a reservoir of promising subsamples for future breeding programs of the species in the northern Amazon.

  10. Variability in population abundance is associated with thresholds between scaling regimes

    Science.gov (United States)

    Wardwell, D.; Allen, Craig R.

    2009-01-01

    Discontinuous structure in landscapes may result in discontinuous, aggregated species body-mass patterns, reflecting the scales of structure available to animal communities within a landscape. The edges of these body-mass aggregations reflect transitions between available scales of landscape structure. Such transitions, or scale breaks, are theoretically associated with increased biological variability. We hypothesized that variability in population abundance is greater in animal species near the edge of body-mass aggregations than it is in species that are situated in the interior of body-mass aggregations. We tested this hypothesis by examining both temporal and spatial variability in the abundance of species in the bird community of the Florida Everglades sub-ecoregion, USA. Analyses of both temporal and spatial variability in population abundance supported our hypothesis. Our results indicate that variability within complex systems may be non-random, and is heightened where transitions in scales of process and structure occur. This is the first explicit test of the hypothetical relationship between increased population variability and scale breaks. ?? 2009 by the author(s).

  11. Temporal dynamics of genetic variability in a mountain goat (Oreamnos americanus) population.

    Science.gov (United States)

    Ortego, Joaquín; Yannic, Glenn; Shafer, Aaron B A; Mainguy, Julien; Festa-Bianchet, Marco; Coltman, David W; Côté, Steeve D

    2011-04-01

    The association between population dynamics and genetic variability is of fundamental importance for both evolutionary and conservation biology. We combined long-term population monitoring and molecular genetic data from 123 offspring and their parents at 28 microsatellite loci to investigate changes in genetic diversity over 14 cohorts in a small and relatively isolated population of mountain goats (Oreamnos americanus) during a period of demographic increase. Offspring heterozygosity decreased while parental genetic similarity and inbreeding coefficients (F(IS) ) increased over the study period (1995-2008). Immigrants introduced three novel alleles into the population and matings between residents and immigrants produced more heterozygous offspring than local crosses, suggesting that immigration can increase population genetic variability. The population experienced genetic drift over the study period, reflected by a reduced allelic richness over time and an 'isolation-by-time' pattern of genetic structure. The temporal decline of individual genetic diversity despite increasing population size probably resulted from a combination of genetic drift due to small effective population size, inbreeding and insufficient counterbalancing by immigration. This study highlights the importance of long-term genetic monitoring to understand how demographic processes influence temporal changes of genetic diversity in long-lived organisms. © 2011 Blackwell Publishing Ltd.

  12. Population and prehistory III: food-dependent demography in variable environments.

    Science.gov (United States)

    Lee, Charlotte T; Puleston, Cedric O; Tuljapurkar, Shripad

    2009-11-01

    The population dynamics of preindustrial societies depend intimately on their surroundings, and food is a primary means through which environment influences population size and individual well-being. Food production requires labor; thus, dependence of survival and fertility on food involves dependence of a population's future on its current state. We use a perturbation approach to analyze the effects of random environmental variation on this nonlinear, age-structured system. We show that in expanding populations, direct environmental effects dominate induced population fluctuations, so environmental variability has little effect on mean hunger levels, although it does decrease population growth. The growth rate determines the time until population is limited by space. This limitation introduces a tradeoff between population density and well-being, so population effects become more important than the direct effects of the environment: environmental fluctuation increases mortality, releasing density dependence and raising average well-being for survivors. We discuss the social implications of these findings for the long-term fate of populations as they transition from expansion into limitation, given that conditions leading to high well-being during growth depress well-being during limitation.

  13. The Influence of Matching Populations on Kinematic and Kinetic Variables in Runners with Iliotibial Band Syndrome

    Science.gov (United States)

    Grau, Stefan; Maiwald, Christian; Krauss, Inga; Axmann, Detlef; Horstmann, Thomas

    2008-01-01

    The purpose of this study was to assess how participant matching influences biomechanical variables when comparing healthy runners and runners with iliotibial band syndrome (ITBS). We examined 52 healthy runners (CO) and 18 with ITBS, using three-dimensional kinematics and pressure distribution. The study population was matched in three ways and…

  14. Genetic variability in captive populations of the stingless bee Tetragonisca angustula.

    Science.gov (United States)

    Santiago, Leandro R; Francisco, Flávio O; Jaffé, Rodolfo; Arias, Maria C

    2016-08-01

    Low genetic variability has normally been considered a consequence of animal husbandry and a major contributing factor to declining bee populations. Here, we performed a molecular analysis of captive and wild populations of the stingless bee Tetragonisca angustula, one of the most commonly kept species across South America. Microsatellite analyses showed similar genetic variability between wild and captive populations However, captive populations showed lower mitochondrial genetic variability. Male-mediated gene flow, transport and division of nests are suggested as the most probable explanations for the observed patterns of genetic structure. We conclude that increasing the number of colonies kept through nest divisions does not negatively affect nuclear genetic variability, which seems to be maintained by small-scale male dispersal and human-mediated nest transport. However, the transport of nests from distant localities should be practiced with caution given the high genetic differentiation observed between samples from western and eastern areas. The high genetic structure verified is the result of a long-term evolutionary process, and bees from distant localities may represent unique evolutionary lineages.

  15. Variability of rooting in a small second-generation population of the hybrid Pinus attenuradiata

    Science.gov (United States)

    J. W. Duffield; A. R. Liddicoet

    1949-01-01

    Propagation of conifers by rooting of cuttings is an old art that has recently benefited by the findings of the plant physiologist. The forest tree breeder may now use rooting as a tool in his efforts to evaluate the heredity of his trees. In a study undertaken to use vegetative propagation of members of a variable hybrid population as a guide for selecting superior...

  16. Local variability mediates vulnerability of trout populations to land use and climate change

    Science.gov (United States)

    Brooke E. Penaluna; Jason B. Dunham; Steve F. Railsback; Ivan Arismendi; Sherri L. Johnson; Robert E. Bilby; Mohammad Safeeq; Arne E. Skaugset; James P. Meador

    2015-01-01

    Land use and climate change occur simultaneously around the globe. Fully understanding their separate and combined effects requires a mechanistic understanding at the local scale where their effects are ultimately realized. Here we applied an individual-based model of fish population dynamics to evaluate the role of local stream variability in modifying responses of...

  17. CRISPR/Cas9 gene drives in genetically variable and nonrandomly mating wild populations.

    Science.gov (United States)

    Drury, Douglas W; Dapper, Amy L; Siniard, Dylan J; Zentner, Gabriel E; Wade, Michael J

    2017-05-01

    Synthetic gene drives based on CRISPR/Cas9 have the potential to control, alter, or suppress populations of crop pests and disease vectors, but it is unclear how they will function in wild populations. Using genetic data from four populations of the flour beetle Tribolium castaneum , we show that most populations harbor genetic variants in Cas9 target sites, some of which would render them immune to drive (ITD). We show that even a rare ITD allele can reduce or eliminate the efficacy of a CRISPR/Cas9-based synthetic gene drive. This effect is equivalent to and accentuated by mild inbreeding, which is a characteristic of many disease-vectoring arthropods. We conclude that designing such drives will require characterization of genetic variability and the mating system within and among targeted populations.

  18. Population activity statistics dissect subthreshold and spiking variability in V1.

    Science.gov (United States)

    Bányai, Mihály; Koman, Zsombor; Orbán, Gergő

    2017-07-01

    Response variability, as measured by fluctuating responses upon repeated performance of trials, is a major component of neural responses, and its characterization is key to interpret high dimensional population recordings. Response variability and covariability display predictable changes upon changes in stimulus and cognitive or behavioral state, providing an opportunity to test the predictive power of models of neural variability. Still, there is little agreement on which model to use as a building block for population-level analyses, and models of variability are often treated as a subject of choice. We investigate two competing models, the doubly stochastic Poisson (DSP) model assuming stochasticity at spike generation, and the rectified Gaussian (RG) model tracing variability back to membrane potential variance, to analyze stimulus-dependent modulation of both single-neuron and pairwise response statistics. Using a pair of model neurons, we demonstrate that the two models predict similar single-cell statistics. However, DSP and RG models have contradicting predictions on the joint statistics of spiking responses. To test the models against data, we build a population model to simulate stimulus change-related modulations in pairwise response statistics. We use single-unit data from the primary visual cortex (V1) of monkeys to show that while model predictions for variance are qualitatively similar to experimental data, only the RG model's predictions are compatible with joint statistics. These results suggest that models using Poisson-like variability might fail to capture important properties of response statistics. We argue that membrane potential-level modeling of stochasticity provides an efficient strategy to model correlations. NEW & NOTEWORTHY Neural variability and covariability are puzzling aspects of cortical computations. For efficient decoding and prediction, models of information encoding in neural populations hinge on an appropriate model of

  19. Disaggregating measurement uncertainty from population variability and Bayesian treatment of uncensored results

    International Nuclear Information System (INIS)

    Strom, Daniel J.; Joyce, Kevin E.; Maclellan, Jay A.; Watson, David J.; Lynch, Timothy P.; Antonio, Cheryl L.; Birchall, Alan; Anderson, Kevin K.; Zharov, Peter

    2012-01-01

    In making low-level radioactivity measurements of populations, it is commonly observed that a substantial portion of net results are negative. Furthermore, the observed variance of the measurement results arises from a combination of measurement uncertainty and population variability. This paper presents a method for disaggregating measurement uncertainty from population variability to produce a probability density function (PDF) of possibly true results. To do this, simple, justifiable, and reasonable assumptions are made about the relationship of the measurements to the measurands (the 'true values'). The measurements are assumed to be unbiased, that is, that their average value is the average of the measurands. Using traditional estimates of each measurement's uncertainty to disaggregate population variability from measurement uncertainty, a PDF of measurands for the population is produced. Then, using Bayes's theorem, the same assumptions, and all the data from the population of individuals, a prior PDF is computed for each individual's measurand. These PDFs are non-negative, and their average is equal to the average of the measurement results for the population. The uncertainty in these Bayesian posterior PDFs is all Berkson with no remaining classical component. The methods are applied to baseline bioassay data from the Hanford site. The data include 90Sr urinalysis measurements on 128 people, 137Cs in vivo measurements on 5,337 people, and 239Pu urinalysis measurements on 3,270 people. The method produces excellent results for the 90Sr and 137Cs measurements, since there are nonzero concentrations of these global fallout radionuclides in people who have not been occupationally exposed. The method does not work for the 239Pu measurements in non-occupationally exposed people because the population average is essentially zero.

  20. Population structure, fluctuating asymmetry and genetic variability in an endemic and highly isolated Astyanax fish population (Characidae

    Directory of Open Access Journals (Sweden)

    Maria Claudia Gross

    2004-01-01

    Full Text Available Morphological and chromosomal markers were used to infer the structure and genetic variability of a population of fish of the genus Astyanax, geographically isolated at sinkhole 2 of Vila Velha State Park, Paraná, Brazil. Two morphotypes types were observed, the standard phenotype I and phenotype II which showed an anatomical alteration probably due to an inbreeding process. Fluctuating asymmetry (FA analysis of different characters showed low levels of morphological variation among the population from sinkhole 2 and in another population from the Tibagi river (Paraná, Brazil. The Astyanax karyotype was characterized in terms of chromosomal morphology, constitutive heterochromatin and nucleolar organizer regions. Males and females presented similar karyotypes (2n=48, 6M+18SM+14ST+10A with no evidence of a sex chromosome system. One female from sinkhole 2 was a natural triploid with 2n=3x=72 chromosomes (9M+27SM+21ST+15A. The data are discussed regarding the maintenance of population structure and their evolutionary importance, our data suggesting that Astyanax from the Vila Velha State Park sinkhole 2 is a recently isolated population.

  1. Spatial variability and macro‐scale drivers of growth for native and introduced Flathead Catfish populations

    Science.gov (United States)

    Massie, Danielle L.; Smith, Geoffrey; Bonvechio, Timothy F.; Bunch, Aaron J.; Lucchesi, David O.; Wagner, Tyler

    2018-01-01

    Quantifying spatial variability in fish growth and identifying large‐scale drivers of growth are fundamental to many conservation and management decisions. Although fish growth studies often focus on a single population, it is becoming increasingly clear that large‐scale studies are likely needed for addressing transboundary management needs. This is particularly true for species with high recreational value and for those with negative ecological consequences when introduced outside of their native range, such as the Flathead Catfish Pylodictis olivaris. This study quantified growth variability of the Flathead Catfish across a large portion of its contemporary range to determine whether growth differences existed between habitat types (i.e., reservoirs and rivers) and between native and introduced populations. Additionally, we investigated whether growth parameters varied as a function of latitude and time since introduction (for introduced populations). Length‐at‐age data from 26 populations across 11 states in the USA were modeled using a Bayesian hierarchical von Bertalanffy growth model. Population‐specific growth trajectories revealed large variation in Flathead Catfish growth and relatively high uncertainty in growth parameters for some populations. Relatively high uncertainty was also evident when comparing populations and when quantifying large‐scale patterns. Growth parameters (Brody growth coefficient [K] and theoretical maximum average length [L∞]) were not different (based on overlapping 90% credible intervals) between habitat types or between native and introduced populations. For populations within the introduced range of Flathead Catfish, latitude was negatively correlated with K. For native populations, we estimated an 85% probability that L∞ estimates were negatively correlated with latitude. Contrary to predictions, time since introduction was not correlated with growth parameters in introduced populations of Flathead Catfish

  2. Neural and psychological underpinnings of gambling disorder

    DEFF Research Database (Denmark)

    Grant, Jon E; Odlaug, Brian L; Chamberlain, Samuel R

    2016-01-01

    Gambling disorder affects 0.4 to 1.6% of adults worldwide, and is highly comorbid with other mental health disorders. This article provides a concise primer on the neural and psychological underpinnings of gambling disorder based on a selective review of the literature. Gambling disorder is assoc......Gambling disorder affects 0.4 to 1.6% of adults worldwide, and is highly comorbid with other mental health disorders. This article provides a concise primer on the neural and psychological underpinnings of gambling disorder based on a selective review of the literature. Gambling disorder...... is associated with dysfunction across multiple cognitive domains which can be considered in terms of impulsivity and compulsivity. Neuroimaging data suggest structural and functional abnormalities of networks involved in reward processing and top-down control. Gambling disorder shows 50-60% heritability...... is required to evaluate whether cognitive dysfunction and personality aspects influence the longitudinal course and treatment outcome for gambling disorder. It is hoped that improved understanding of the biological and psychological components of gambling disorder, and their interactions, may lead to improved...

  3. The relationship of sociodemographic and psychological variables with chronic pain variables in a low-income population.

    Science.gov (United States)

    Newman, Andrea K; Van Dyke, Benjamin P; Torres, Calia A; Baxter, Jacob W; Eyer, Joshua C; Kapoor, Shweta; Thorn, Beverly E

    2017-09-01

    Chronic pain is a pervasive condition that is complicated by economic, educational, and racial disparities. This study analyzes key factors associated with chronic pain within an understudied and underserved population. The sample is characterized by a triple disparity with respect to income, education/literacy, and racial barriers that substantially increase the vulnerability to the negative consequences of chronic pain. The study examined the pretreatment data of 290 participants enrolled in the Learning About My Pain trial, a randomized controlled comparative effectiveness trial of psychosocial interventions (B.E.T., Principal Investigator, Patient-Centered Outcomes Research Institute Contract No. 941; clinicaltrials.gov identifier NCT01967342) for chronic pain. Hierarchical multiple regression analyses evaluated the relationships among sociodemographic (sex, age, race, poverty status, literacy, and education level) and psychological (depressive symptoms and pain catastrophizing) variables and pain interference, pain severity, and disability. The indirect effects of depressive symptoms and pain catastrophizing on the sociodemographic and pain variables were investigated using bootstrap resampling. Reversed mediation models were also examined. Results suggested that the experience of chronic pain within this low-income sample is better accounted for by psychological factors than sex, age, race, poverty status, literacy, and education level. Depressive symptoms and pain catastrophizing mediated the relationships between age and pain variables, whereas pain catastrophizing mediated the effects of primary literacy and poverty status. Some reversed models were equivalent to the hypothesized models, suggesting the possibility of bidirectionality. Although cross-sectional findings cannot establish causality, our results highlight the critical role psychological factors play in individuals with chronic pain and multiple health disparities.

  4. Use of the IRAP marker to study genetic variability in Pseudocercospora fijiensis populations.

    Science.gov (United States)

    de Queiroz, Casley Borges; Santana, Mateus Ferreira; da Silva, Gilvan Ferreira; Mizubuti, Eduardo Seiti Gomide; de Araújo, Elza Fernandes; de Queiroz, Marisa Vieira

    2014-03-01

    Pseudocercospora fijiensis is the etiological agent of black Sigatoka, which is currently considered as one of the most destructive banana diseases in all locations where it occurs. It is estimated that a large portion of the P. fijiensis genome consists of transposable elements, which allows researchers to use transposon-based molecular markers in the analysis of genetic variability in populations of this pathogen. In this context, the inter-retrotransposon-amplified polymorphism (IRAP) was used to study the genetic variability in P. fijiensis populations from different hosts and different geographical origins in Brazil. A total of 22 loci were amplified and 77.3 % showed a polymorphism. Cluster analysis revealed two major groups in Brazil. The observed genetic diversity (H E) was 0.22, and through molecular analysis of variance, it was determined that the greatest genetic variability occurs within populations. The discriminant analysis of principal components revealed no structuring related to the geographical origin of culture of the host. The IRAP-based marker system is a suitable tool for the study of genetic variability in P. fijiensis.

  5. Speaker Input Variability Does Not Explain Why Larger Populations Have Simpler Languages.

    Science.gov (United States)

    Atkinson, Mark; Kirby, Simon; Smith, Kenny

    2015-01-01

    A learner's linguistic input is more variable if it comes from a greater number of speakers. Higher speaker input variability has been shown to facilitate the acquisition of phonemic boundaries, since data drawn from multiple speakers provides more information about the distribution of phonemes in a speech community. It has also been proposed that speaker input variability may have a systematic influence on individual-level learning of morphology, which can in turn influence the group-level characteristics of a language. Languages spoken by larger groups of people have less complex morphology than those spoken in smaller communities. While a mechanism by which the number of speakers could have such an effect is yet to be convincingly identified, differences in speaker input variability, which is thought to be larger in larger groups, may provide an explanation. By hindering the acquisition, and hence faithful cross-generational transfer, of complex morphology, higher speaker input variability may result in structural simplification. We assess this claim in two experiments which investigate the effect of such variability on language learning, considering its influence on a learner's ability to segment a continuous speech stream and acquire a morphologically complex miniature language. We ultimately find no evidence to support the proposal that speaker input variability influences language learning and so cannot support the hypothesis that it explains how population size determines the structural properties of language.

  6. Landscape attributes and life history variability shape genetic structure of trout populations in a stream network

    Science.gov (United States)

    Neville, H.M.; Dunham, J.B.; Peacock, M.M.

    2006-01-01

    Spatial and temporal landscape patterns have long been recognized to influence biological processes, but these processes often operate at scales that are difficult to study by conventional means. Inferences from genetic markers can overcome some of these limitations. We used a landscape genetics approach to test hypotheses concerning landscape processes influencing the demography of Lahontan cutthroat trout in a complex stream network in the Great Basin desert of the western US. Predictions were tested with population- and individual-based analyses of microsatellite DNA variation, reflecting patterns of dispersal, population stability, and local effective population sizes. Complementary genetic inferences suggested samples from migratory corridors housed a mixture of fish from tributaries, as predicted based on assumed migratory life histories in those habitats. Also as predicted, populations presumed to have greater proportions of migratory fish or from physically connected, large, or high quality habitats had higher genetic variability and reduced genetic differentiation from other populations. Populations thought to contain largely non-migratory individuals generally showed the opposite pattern, suggesting behavioral isolation. Estimated effective sizes were small, and we identified significant and severe genetic bottlenecks in several populations that were isolated, recently founded, or that inhabit streams that desiccate frequently. Overall, this work suggested that Lahontan cutthroat trout populations in stream networks are affected by a combination of landscape and metapopulation processes. Results also demonstrated that genetic patterns can reveal unexpected processes, even within a system that is well studied from a conventional ecological perspective. ?? Springer 2006.

  7. Genetic variability and population structure of Plasmodium falciparum parasite populations from different malaria ecological regions of Kenya.

    Science.gov (United States)

    Ingasia, Luicer A; Cheruiyot, Jelagat; Okoth, Sheila Akinyi; Andagalu, Ben; Kamau, Edwin

    2016-04-01

    Transmission intensity, movement of human and vector hosts, biogeographical features, and malaria control measures are some of the important factors that determine Plasmodium falciparum parasite genetic variability and population structure. Kenya has different malaria ecologies which might require different disease intervention methods. Refined parasite population genetic studies are critical for informing malaria control and elimination strategies. This study describes the genetic diversity and population structure of P. falciparum parasites from the different malaria ecological zones in Kenya. Twelve multi-locus microsatellite (MS) loci previously described were genotyped in 225 P. falciparum isolates collected between 2012 and 2013 from five sites; three in lowland endemic regions (Kisumu, Kombewa, and Malindi) and two in highland, epidemic regions (Kisii and Kericho). Parasites from the lowland endemic and highland epidemic regions of western Kenya had high genetic diversity compared to coastal lowland endemic region of Kenya [Malindi]. The Kenyan parasites had a mean genetic differentiation index (FST) of 0.072 (p=0.011). The multi-locus genetic analysis of the 12 MS revealed all the parasites had unique haplotypes. Significant linkage disequilibrium (LD) was observed in all the five parasite populations. Kisumu had the most significant index of association values (0.16; pKenya after introduction of the artemether-lumefantrine is important in refining the spread of drug resistant strains and malaria transmission for more effective control and eventual elimination of malaria in Kenya. Copyright © 2015. Published by Elsevier B.V.

  8. Inter-Population Variability of Endosymbiont Densities in the Asian Citrus Psyllid (Diaphorina citri Kuwayama).

    Science.gov (United States)

    Chu, Chia-Ching; Gill, Torrence A; Hoffmann, Mark; Pelz-Stelinski, Kirsten S

    2016-05-01

    The Asian citrus psyllid (Diaphorina citri Kuwayama) is an insect pest capable of transmitting Candidatus Liberibacter asiaticus (CLas), the causal agent of citrus greening in North America. D. citri also harbors three endosymbionts, Wolbachia, Candidatus Carsonella ruddii, and Candidatus Profftella armatura, which may influence D. citri physiology and fitness. Although genomic researches on these bacteria have been conducted, much remains unclear regarding their ecology and inter-population variability in D. citri. The present work examined the densities of each endosymbiont in adult D. citri sampled from different populations using quantitative PCR. Under field conditions, the densities of all three endosymbionts positively correlated with each other, and they are associated with D. citri gender and locality. In addition, the infection density of CLas also varied across populations. Although an analysis pooling D. citri from different populations showed that CLas-infected individuals tended to have lower endosymbiont densities compared to uninfected individuals, the difference was not significant when the population was included as a factor in the analysis, suggesting that other population-specific factors may have stronger effects on endosymbiont densities. To determine whether there is a genetic basis to the density differences, endosymbiont densities between aged CLas-negative females of two D. citri populations reared under standardized laboratory conditions were compared. Results suggested that inter-population variability in Wolbachia infection density is associated with the genotypes of the endosymbiont or the host. Findings from this work could facilitate understanding of D. citri-bacterial associations that may benefit the development of approaches for managing citrus greening, such as prevention of CLas transmission.

  9. In vitro screening for population variability in toxicity of pesticide-containing mixtures

    Science.gov (United States)

    Abdo, Nour; Wetmore, Barbara A.; Chappell, Grace A.; Shea, Damian; Wright, Fred A.; Rusyna, Ivan

    2016-01-01

    Population-based human in vitro models offer exceptional opportunities for evaluating the potential hazard and mode of action of chemicals, as well as variability in responses to toxic insults among individuals. This study was designed to test the hypothesis that comparative population genomics with efficient in vitro experimental design can be used for evaluation of the potential for hazard, mode of action, and the extent of population variability in responses to chemical mixtures. We selected 146 lymphoblast cell lines from 4 ancestrally and geographically diverse human populations based on the availability of genome sequence and basal RNA-seq data. Cells were exposed to two pesticide mixtures – an environmental surface water sample comprised primarily of organochlorine pesticides and a laboratory-prepared mixture of 36 currently used pesticides – in concentration response and evaluated for cytotoxicity. On average, the two mixtures exhibited a similar range of in vitro cytotoxicity and showed considerable inter-individual variability across screened cell lines. However, when in vitroto-in vivo extrapolation (IVIVE) coupled with reverse dosimetry was employed to convert the in vitro cytotoxic concentrations to oral equivalent doses and compared to the upper bound of predicted human exposure, we found that a nominally more cytotoxic chlorinated pesticide mixture is expected to have greater margin of safety (more than 5 orders of magnitude) as compared to the current use pesticide mixture (less than 2 orders of magnitude) due primarily to differences in exposure predictions. Multivariate genome-wide association mapping revealed an association between the toxicity of current use pesticide mixture and a polymorphism in rs1947825 in C17orf54. We conclude that a combination of in vitro human population-based cytotoxicity screening followed by dosimetric adjustment and comparative population genomics analyses enables quantitative evaluation of human health hazard

  10. Dynamics of sexual populations structured by a space variable and a phenotypical trait

    KAUST Repository

    Mirrahimi, Sepideh

    2013-03-01

    We study sexual populations structured by a phenotypic trait and a space variable, in a non-homogeneous environment. Departing from an infinitesimal model, we perform an asymptotic limit to derive the system introduced in Kirkpatrick and Barton (1997). We then perform a further simplification to obtain a simple model. Thanks to this simpler equation, we can describe rigorously the dynamics of the population. In particular, we provide an explicit estimate of the invasion speed, or extinction speed of the species. Numerical computations show that this simple model provides a good approximation of the original infinitesimal model, and in particular describes quite well the evolution of the species\\' range. © 2013 Elsevier Inc.

  11. Dynamics of sexual populations structured by a space variable and a phenotypical trait

    KAUST Repository

    Mirrahimi, Sepideh; Raoul, Gaë l

    2013-01-01

    We study sexual populations structured by a phenotypic trait and a space variable, in a non-homogeneous environment. Departing from an infinitesimal model, we perform an asymptotic limit to derive the system introduced in Kirkpatrick and Barton (1997). We then perform a further simplification to obtain a simple model. Thanks to this simpler equation, we can describe rigorously the dynamics of the population. In particular, we provide an explicit estimate of the invasion speed, or extinction speed of the species. Numerical computations show that this simple model provides a good approximation of the original infinitesimal model, and in particular describes quite well the evolution of the species' range. © 2013 Elsevier Inc.

  12. Developmental plasticity and epigenetic mechanisms underpinning metabolic and cardiovascular diseases.

    Science.gov (United States)

    Low, Felicia M; Gluckman, Peter D; Hanson, Mark A

    2011-06-01

    The importance of developmental factors in influencing the risk of later-life disease has a strong evidence base derived from multiple epidemiological, clinical and experimental studies in animals and humans. During early life, an organism is able to adjust its phenotypic development in response to environmental cues. Such developmentally plastic responses evolved as a fitness-maximizing strategy to cope with variable environments. There are now increasing data that these responses are, at least partially, underpinned by epigenetic mechanisms. A mismatch between the early and later-life environments may lead to inappropriate early life-course epigenomic changes that manifest in later life as increased vulnerability to disease. There is also growing evidence for the transgenerational transmission of epigenetic marks. This article reviews the evidence that susceptibility to metabolic and cardiovascular disease in humans is linked to changes in epigenetic marks induced by early-life environmental cues, and discusses the clinical, public health and therapeutic implications that arise.

  13. Comparison of Three Plot Selection Methods for Estimating Change in Temporally Variable, Spatially Clustered Populations.

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, William L. [Bonneville Power Administration, Portland, OR (US). Environment, Fish and Wildlife

    2001-07-01

    Monitoring population numbers is important for assessing trends and meeting various legislative mandates. However, sampling across time introduces a temporal aspect to survey design in addition to the spatial one. For instance, a sample that is initially representative may lose this attribute if there is a shift in numbers and/or spatial distribution in the underlying population that is not reflected in later sampled plots. Plot selection methods that account for this temporal variability will produce the best trend estimates. Consequently, I used simulation to compare bias and relative precision of estimates of population change among stratified and unstratified sampling designs based on permanent, temporary, and partial replacement plots under varying levels of spatial clustering, density, and temporal shifting of populations. Permanent plots produced more precise estimates of change than temporary plots across all factors. Further, permanent plots performed better than partial replacement plots except for high density (5 and 10 individuals per plot) and 25% - 50% shifts in the population. Stratified designs always produced less precise estimates of population change for all three plot selection methods, and often produced biased change estimates and greatly inflated variance estimates under sampling with partial replacement. Hence, stratification that remains fixed across time should be avoided when monitoring populations that are likely to exhibit large changes in numbers and/or spatial distribution during the study period. Key words: bias; change estimation; monitoring; permanent plots; relative precision; sampling with partial replacement; temporary plots.

  14. Microsatellite variability reveals high genetic diversity and low genetic differentiation in a critical giant panda population

    Directory of Open Access Journals (Sweden)

    Jiandong YANG, Zhihe ZHANG, Fujun SHEN, Xuyu YANG, Liang ZHANG, Limin CHEN, Wenping ZHANG, Qing ZHU, Rong HOU

    2011-12-01

    Full Text Available Understanding present patterns of genetic diversity is critical in order to design effective conservation and management strategies for endangered species. Tangjiahe Nature Reserve (NR is one of the most important national reserves for giant pandas Ailuropoda melanoleuca in China. Previous studies have shown that giant pandas in Tangjiahe NR may be threatened by population decline and fragmentation. Here we used 10 microsatellite DNA markers to assess the genetic variability in the Tangjiahe population. The results indicate a low level of genetic differentiation between the Hongshihe and Motianling subpopulations in the reserve. Assignment tests using the Bayesian clustering method in STRUCTURE identified one genetic cluster from 42 individuals of the two subpopulations. All individuals from the same subpopulation were assigned to one cluster. This indicates high gene flow between subpopulations. F statistic analyses revealed a low FIS-value of 0.024 in the total population and implies a randomly mating population in Tangjiahe NR. Additionally, our data show a high level of genetic diversity for the Tangjiahe population. Mean allele number (A, Allelic richness (AR and mean expected heterozygosity (HE for the Tangjiahe population was 5.9, 5.173 and 0.703, respectively. This wild giant panda population can be restored through concerted effort [Current Zoology 57 (6: 717–724, 2011].

  15. Variability of the needle essential oils of Pinus peuce from different populations in Montenegro and Serbia.

    Science.gov (United States)

    Nikolić, Biljana; Ristić, Mihailo; Bojović, Srdjan; Marin, Petar D

    2008-07-01

    The essential-oil composition of Pinus peuce Griseb. is reported at the population level. Macedonian pine is endemic high-mountain Balkan pine relict of an anthropogenically reduced area, with large morphological diversity and insufficiently clear taxonomic position. In the pine-needle terpene profile of two populations from Montenegro and one from Serbia, 78 compounds were detected, 56 of which are identified (Table 3). The dominant constituents were alpha-pinene (36.5%) and germacrene D (11.4%). The following 20 additional components were found to be present in medium-to-high amounts (0.5-10%): camphene (8.5%), bornyl acetate (6.8%), beta-pinene (6.8%), beta-caryophyllene (5.2%), beta-phellandrene (4.7%), terpinen-4-ol acetate (1.6%), (E)-hex-2-enal (1.5%), alpha-muurolene (1.2%), beta-gurjunene (1.1%), beta-myrcene (1.0%), alpha-terpinyl acetate (0.9%), alpha-phellandrene (0.8%), delta-cadinene (0.8%), alpha-humulene (0.8%), sabinene (0.7%), aromadendrene (0.6%), alpha-thujene (0.6%), gamma-muurolene (0.6%), gamma-cadinene (0.6%), alpha-terpinolene (0.5%), and one unknown component (0.5%). The similarity of the populations and the within-population variability were visualized by principle-component analysis (PCA) and genetic analysis of selected terpenes in 90 tree samples. Our study suggests a closer connection between populations II and III compared to population I. Based on the profile of the main terpene components, the studied populations are more similar to populations from Kosovo and Greece than to the population from Mt. Mokra (Montenegro) and the population in France.

  16. Effects of uncertainty and variability on population declines and IUCN Red List classifications.

    Science.gov (United States)

    Rueda-Cediel, Pamela; Anderson, Kurt E; Regan, Tracey J; Regan, Helen M

    2018-01-22

    The International Union for Conservation of Nature (IUCN) Red List Categories and Criteria is a quantitative framework for classifying species according to extinction risk. Population models may be used to estimate extinction risk or population declines. Uncertainty and variability arise in threat classifications through measurement and process error in empirical data and uncertainty in the models used to estimate extinction risk and population declines. Furthermore, species traits are known to affect extinction risk. We investigated the effects of measurement and process error, model type, population growth rate, and age at first reproduction on the reliability of risk classifications based on projected population declines on IUCN Red List classifications. We used an age-structured population model to simulate true population trajectories with different growth rates, reproductive ages and levels of variation, and subjected them to measurement error. We evaluated the ability of scalar and matrix models parameterized with these simulated time series to accurately capture the IUCN Red List classification generated with true population declines. Under all levels of measurement error tested and low process error, classifications were reasonably accurate; scalar and matrix models yielded roughly the same rate of misclassifications, but the distribution of errors differed; matrix models led to greater overestimation of extinction risk than underestimations; process error tended to contribute to misclassifications to a greater extent than measurement error; and more misclassifications occurred for fast, rather than slow, life histories. These results indicate that classifications of highly threatened taxa (i.e., taxa with low growth rates) under criterion A are more likely to be reliable than for less threatened taxa when assessed with population models. Greater scrutiny needs to be placed on data used to parameterize population models for species with high growth rates

  17. Effects of Population Growth and Climate Variability on Sustainable Groundwater in Mali, West Africa

    Directory of Open Access Journals (Sweden)

    Alexandra Lutz

    2010-12-01

    Full Text Available Groundwater is increasingly relied on as a source of potable water in developing countries, but factors such as population growth, development, and climate variability, pose potential challenges for ongoing sustainable supply. The effect of these factors on the groundwater system was considered in four scenarios using a numerical model to represent the Bani area of Mali, West Africa. By 2040, population growth, climate variability, and development as urbanization, agriculture, and industry creates scenarios in which groundwater extraction is an increasingly larger percentage of the groundwater system. Consumption from agriculture and industry increases extraction rates from less than 1 to 3.8% of mean annual precipitation, which will likely affect the groundwater system. For instance, concentrated pumping in local areas may result in water level declines. The results of this study contribute to an ongoing evaluation of sustainable groundwater resources in West Africa.

  18. Population, education and sustainable development.

    Science.gov (United States)

    Johnston, T

    1992-12-01

    The author examines the interrelationships between population growth and education, with a focus on Sub-Saharan Africa. "The gross body of evidence suggests that for all developing regions (and for sub-saharan Africa specifically) rapid population growth deleteriously impacts upon the quantity and quality of schooling. In a reciprocal fashion, the variables which underpin rapid and differential growth (fertility, mortality and migration) are themselves influenced by quantum of formal schooling and by other educational processes." excerpt

  19. Genetic variability in chronic irradiated plant populations - Polymorphism and activity of antioxidant enzymes in chronic irradiated plant populations

    Energy Technology Data Exchange (ETDEWEB)

    Volkova, Polina Y.; Geras' kin, Stanislav A. [Russian Institute of Agricultural Radiology and Agroecology, 249030, Obninsk, Kievskoe shosse 109 km (Russian Federation)

    2014-07-01

    Introduction: The gene pool of natural population is constantly changing in order to provide the greatest fitness at this time. Ability of population to adapt to changing environmental conditions depends on genetic polymorphism of traits which are operates by selection. Chronic stress exposure can change amount or structure intra-population variability. Therefore, it is necessary to analyze the relationships between genetic polymorphism and stress factors, such as radiation exposure. This studies my assist in the development of new bio-indication methods. Materials and methods: Studying sites: Bryansk region is the most contaminated region of Russia as a result of Chernobyl accident. The initial activity by {sup 137}Cs on this territory reached 1 MBq/m{sup 2} above surface. Our study conducted in several districts of Bryansk region, which are characterized the most dose rate. Experimental sites similar to climate characteristics, stand of trees is homogeneous, pine trees take up a significant part of phytocenosis. Heavy metals content in soils and cones be within background. Dose rates vary from 0.14 to 130 mGy/year. Object: Pinus sylvestris L.,the dominant tree species in North European and Asian boreal forests. Scots pine has a long maturation period (18-20 month), which means that significant DNA damage may accumulate in the undifferentiated stem cells, even at low doses (or dose rates) during exposure to low concentrations of contaminants Isozyme analysis: We evaluated isozyme polymorphism of three antioxidant enzymes: superoxide dismutase, glutatione reductase and glutatione peroxidase. Analysis of enzymes activities: We chose key enzymes of antioxidant system for this experiment: superoxide dismutase, catalase and peroxidase. Results and conclusions: We estimated frequency of each allele in reference and experimental populations. based It was showed that frequency of rare alleles increase in chronic irradiated populations, i.e. increase the sampling variance

  20. Karyotype Variability and Inter-Population Genomic Differences in Freshwater Ostracods (Crustacea Showing Geographical Parthenogenesis

    Directory of Open Access Journals (Sweden)

    Radka Symonová

    2018-03-01

    Full Text Available Transitions from sexual to asexual reproduction are often associated with polyploidy and increased chromosomal plasticity in asexuals. We investigated chromosomes in the freshwater ostracod species Eucypris virens (Jurine, 1820, where sexual, asexual and mixed populations can be found. Our initial karyotyping of multiple populations from Europe and North Africa, both sexual and asexual, revealed a striking variability in chromosome numbers. This would suggest that chromosomal changes are likely to be accelerated in asexuals because the constraints of meiosis are removed. Hence, we employed comparative genomic hybridization (CGH within and among sexual and asexual populations to get insights into E. virens genome arrangements. CGH disclosed substantial genomic imbalances among the populations analyzed, and three patterns of genome arrangement between these populations: 1. Only putative ribosomal DNA (rDNA-bearing regions were conserved in the two populations compared indicating a high sequence divergence between these populations. This pattern is comparable with our findings at the interspecies level of comparison; 2. Chromosomal regions were shared by both populations to a varying extent with a distinct copy number variation in pericentromeric and presumable rDNA-bearing regions. This indicates a different rate of evolution in repetitive sequences; 3. A mosaic pattern of distribution of genomic material that can be explained as non-reciprocal genetic introgression and evidence of a hybrid origin of these individuals. We show an overall increased chromosomal dynamics in E. virens that is complementary with available phylogenetic and population genetic data reporting highly differentiated diploid sexual and asexual lineages with a wide variety of genetic backgrounds.

  1. GENETIC VARIABILITY OF THREE POPULATIONS OF FLYING FISH, Hirundichthy oxycephalus FROM MAKASSAR STRAIT

    Directory of Open Access Journals (Sweden)

    Andi Parenrengi

    2016-03-01

    Full Text Available Flying fish, Hirundichthy oxycephalus is one of economically important marine species to Indonesia, particularly in Makassar Strait and Flores Sea. However, there is a limited published data on genetic variation in molecular marker level of this species. Random Amplified Polymorphic DNA (RAPD was employed in this study to determine the genetic variability of three populations of flying fish collected from Takalar, Pare-Pare, and Majene in Makassar Strait. Genomic DNA was isolated from preserved muscle tissue using phenol-chloroform technique. Two selected arbitrary primers (CA-01 and P-40 were performed to generate RAPD finger printing of flying fish populations. The two primers generated a total of 81 fragments (loci and 50 polymorphic fragments with size ranging from 125 to 1,250 bp. There were no significant differences in number of fragment and number of polymorphic fragment among populations. The high polymorphism (63.5±7.4% was obtained from Takalar population followed by Pare-Pare (58.3±19.6% and Majene population (57.7±0.8%. Similarity index of individuals was 0.60±0.17 for Takalar, 0.63±0.17 for Majene and 0.75±0.21 for Pare-Pare population. Seven fragments were identified as species-specific markers of H. oxycephalus. The UPGMA cluster analysis showed that the Takalar population was genetically closer to Pare-Pare population (D= 0.0812 than to Majene population (D= 0.1873.

  2. Role of Obesity Variables in Detecting Hypertension in an Iranian Population.

    Science.gov (United States)

    Khashayar, Patricia; Aghaei Meybodi, Hamidreza; Rezaei Hemami, Mohsen; Larijani, Bagher

    2017-09-01

    As the high incidence of hypertension has been in conjunction with dramatic increase in the prevalence of obesity, many studies have suggested obesity as its underlying cause in diverse race and ethnic groups. The present study was designed to quantify the relationship between obesity variables and hypertension in Iranian population. A ROC curve analysis was also used to determine an optimal BMI cutoff for obesity with the aim of representing elevated incidence of hypertension in this population. The study population comprised of apparently healthy men and women who participated in the Iranian Multi-centric Osteoporosis Studies (IMOS), a multi-centric cross-sectional study carried out in urban areas of five great cities (Tehran, Tabriz, Mashhad, Shiraz and Bushehr). The anthropometric (weight, height, waist and hip circumferences) and blood pressure measures were reported in some 5724 subjects. The influence of these factors on systolic and diastolic blood pressure was assessed based on a list-wise method. There was a significant difference in the studied subjects anthropometric (weight classes (BMI), WC and HC, and WHR) and blood pressure variables; age, gender and weight, however, were the only factors significantly influencing SBP and DBP. Furthermore, BMI showed a significant impact on the overall risk of developing hypertension. General obesity rather than abdominal obesity is directly linked with higher blood pressure levels in Iranian population.

  3. Genetic variability and effective population size when local extinction and recolonization of subpopulations are frequent

    Science.gov (United States)

    Maruyama, Takeo; Kimura, Motoo

    1980-01-01

    If a population (species) consists of n haploid lines (subpopulations) which reproduce asexually and each of which is subject to random extinction and subsequent replacement, it is shown that, at equilibrium in which mutational production of new alleles and their random extinction balance each other, the genetic diversity (1 minus the sum of squares of allelic frequencies) is given by 2Nev/(1 + 2Nev), where [Formula: see text] in which Ñ is the harmonic mean of the population size per line, n is the number of lines (assumed to be large), λ is the rate of line extinction, and v is the mutation rate (assuming the infinite neutral allele model). In a diploid population (species) consisting of n colonies, if migration takes place between colonies at the rate m (the island model) in addition to extinction and recolonization of colonies, it is shown that effective population size is [Formula: see text] If the rate of colony extinction (λ) is much larger than the migration rate of individuals, the effective population size is greatly reduced compared with the case in which no colony extinctions occur (in which case Ne = nÑ). The stepping-stone type of recolonization scheme is also considered. Bearing of these results on the interpretation of the level of genetic variability at the enzyme level observed in natural populations is discussed from the standpoint of the neutral mutation-random drift hypothesis. PMID:16592920

  4. Genetic and phenotypic variability of iris color in Buenos Aires population

    Directory of Open Access Journals (Sweden)

    Diana María Hohl

    Full Text Available Abstract The aim of this work was to describe the phenotypic and genotypic variability related to iris color for the population of Buenos Aires province (Argentina, and to assess the usefulness of current methods of analysis for this country. We studied five Single Nucleotide Polymorphisms (SNPs included in the IrisPlex kit, in 118 individuals, and we quantified eye color with Digital Iris Analysis Tool. The markers fit Hardy-Weinberg equilibrium for the whole sample, but not for rs12913832 within the group of brown eyes (LR=8.429; p=0.004. We found a remarkable association of HERC2 rs12913832 GG with blue color (p < 0.01 but the other markers did not show any association with iris color. The results for the Buenos Aires population differ from those of other populations of the world for these polymorphisms (p < 0,01. The differences we found might respond to the admixed ethnic composition of Argentina; therefore, methods of analysis used in European populations should be carefully applied when studying the population of Argentina. These findings reaffirm the importance of this investigation in the Argentinian population for people identification based on iris color.

  5. Breast dose variability in a bi-racial population undergoing screening mammography

    International Nuclear Information System (INIS)

    Schubauer-Berigan, M.K.; Baron, L.; Frey, G.D.; Hoel, D.G.

    2002-01-01

    This study evaluated individual and population dose variability during screening mammography among 570 white and black women in South Carolina, USA. Aspects of dosimetry that were considered include compressed breast thickness (CBT), number of films per screening session, and dose in previous or subsequent sessions. Breast dose was log-normally distributed in the population, with a geometric mean of 6.6 mGy per session. Doses were significantly higher for black women, for women with high CBT or who receive more than two views per breast, and for the mediolateral oblique, compared to the craniocaudal view. No relationship was observed between age and dose. Total dose per breast varied by a factor of 20 across the study population, but the individual's dose varied little among repeat screening sessions, especially after adjusting for the number of films received per session. These results may inform assessments of the projected risks of inducing breast cancer from screening mammography. (author)

  6. A NEW CENSUS OF THE VARIABLE STAR POPULATION IN THE GLOBULAR CLUSTER NGC 2419

    International Nuclear Information System (INIS)

    Di Criscienzo, M.; Greco, C.; Ripepi, V.; Dall' Ora, M.; Marconi, M.; Musella, I.; Clementini, G.; Federici, L.; Di Fabrizio, L.

    2011-01-01

    We present B, V, and I CCD light curves for 101 variable stars belonging to the globular cluster NGC 2419, 60 of which are new discoveries, based on data sets obtained at the Telescopio Nazionale Galileo, the Subaru telescope, and the Hubble Space Telescope. The sample includes 75 RR Lyrae stars (38 RRab, 36 RRc, and one RRd), one Population II Cepheid, 12 SX Phoenicis variables, two δ Scuti stars, three binary systems, five long-period variables, and three variables of uncertain classification. The pulsation properties of the RR Lyrae variables are close to those of Oosterhoff type II clusters, consistent with the low metal abundance and the cluster horizontal branch morphology, disfavoring (but not totally ruling out) an extragalactic hypothesis for the origin of NGC 2419. The observed properties of RR Lyrae and SX Phoenicis stars are used to estimate the cluster reddening and distance, using a number of different methods. Our final value is μ 0 (NGC 2419) = 19.71 ± 0.08 mag (D = 87.5 ± 3.3 kpc), with E(B - V) = 0.08 ± 0.01 mag, [Fe/H] = -2.1 dex on the Zinn and West metallicity scale, and a value of M V that sets μ 0 (LMC) = 18.52 mag. This value is in good agreement with the most recent literature estimates of the distance to NGC 2419.

  7. Pan genome of the phytoplankton Emiliania underpins its global distribution.

    Science.gov (United States)

    Read, Betsy A; Kegel, Jessica; Klute, Mary J; Kuo, Alan; Lefebvre, Stephane C; Maumus, Florian; Mayer, Christoph; Miller, John; Monier, Adam; Salamov, Asaf; Young, Jeremy; Aguilar, Maria; Claverie, Jean-Michel; Frickenhaus, Stephan; Gonzalez, Karina; Herman, Emily K; Lin, Yao-Cheng; Napier, Johnathan; Ogata, Hiroyuki; Sarno, Analissa F; Shmutz, Jeremy; Schroeder, Declan; de Vargas, Colomban; Verret, Frederic; von Dassow, Peter; Valentin, Klaus; Van de Peer, Yves; Wheeler, Glen; Dacks, Joel B; Delwiche, Charles F; Dyhrman, Sonya T; Glöckner, Gernot; John, Uwe; Richards, Thomas; Worden, Alexandra Z; Zhang, Xiaoyu; Grigoriev, Igor V

    2013-07-11

    Coccolithophores have influenced the global climate for over 200 million years. These marine phytoplankton can account for 20 per cent of total carbon fixation in some systems. They form blooms that can occupy hundreds of thousands of square kilometres and are distinguished by their elegantly sculpted calcium carbonate exoskeletons (coccoliths), rendering them visible from space. Although coccolithophores export carbon in the form of organic matter and calcite to the sea floor, they also release CO2 in the calcification process. Hence, they have a complex influence on the carbon cycle, driving either CO2 production or uptake, sequestration and export to the deep ocean. Here we report the first haptophyte reference genome, from the coccolithophore Emiliania huxleyi strain CCMP1516, and sequences from 13 additional isolates. Our analyses reveal a pan genome (core genes plus genes distributed variably between strains) probably supported by an atypical complement of repetitive sequence in the genome. Comparisons across strains demonstrate that E. huxleyi, which has long been considered a single species, harbours extensive genome variability reflected in different metabolic repertoires. Genome variability within this species complex seems to underpin its capacity both to thrive in habitats ranging from the equator to the subarctic and to form large-scale episodic blooms under a wide variety of environmental conditions.

  8. Pan Genome of the Phytoplankton Emiliania Underpins its Global Distribution

    Energy Technology Data Exchange (ETDEWEB)

    Read, Betsy A. [California State Univ. (CalState), San Marcos, CA (United States); Kegel, Jessica [Alfred Wegener Inst. for Polar and Marine Research, Bremerhaven (Germany); Klute, Mary J. [Univ. of Alberta, Edmonton, AB (Canada); Kuo, Alan [USDOE Joint Genome Inst., Walnut Creek, CA (United States); Lefebvre, Stephane C. [J. Craig Venter Inst., San Diego, CA (United States); Maumus, Florian [National Institute of Agricultural Research, Versailles (France); Mayer, Christoph [Alexander Koenig Research Museum, Bonn (Germany); Ruhr Univ., Bochum (Germany); Miller, John [Univ. of Maryland, College Park, MD (United States); Monier, Adam [Monterey Bay Aquarium Research Inst., Moss Landing, CA (United States); Salamov, Asaf [USDOE Joint Genome Inst., Walnut Creek, CA (United States); Young, Jeremy [Univ. College London (United Kingdom); Aguilar, Maria [Univ. of Alberta, Edmonton, AB (Canada); Claverie, Jean-Michel [Aix-Marseille Univ. (France); Frickenhaus, Stephan [Alfred Wegener Inst. for Polar and Marine Research, Bremerhaven (Germany); Univ. of Bremerhaven (Germany); Gonzalez, Karina [Harvard Medical School, Boston, MA (United States); Herman, Emily K. [Univ. of Alberta, Edmonton, AB (Canada); Lin, Yao-Cheng [Ghent Univ. (Belgium); Napier, Johnathan [Rothamstead Research, Harpenden (United Kingdom); Ogata, Hiroyuki [Aix-Marseille Univ. (France); Sarno, Analissa F. [California State Univ. (CalState), San Marcos, CA (United States); Schmutz, Jeremy [USDOE Joint Genome Inst., Walnut Creek, CA (United States); HudsonAlpha Genome Sequencing Center, Huntsville, AL (United States); Schroeder, Declan [Marine Biological Association of the UK, Plymouth (United Kingdom); de Vargas, Columban [CNRS. Univ. Pierre and Marie Curie (France).; Verret, Frederic [Univ. of Essex, Colchester (United Kingdom); von Dassow, Peter [Pontifical Catholic University of Chile, Santiago (Chile); Valentin, Klaus [Alfred Wegener Inst. for Polar and Marine Research, Bremerhaven (Germany); Van de Peer, Yves [Ghent Univ. (Belgium); Wheeler, Glen [Marine Biological Association of the UK, Plymouth (United Kingdom); Plymouth Marine Lab. (United Kingdom); Annotation Consortium, Emiliania huxleyi; Dacks, Joel B. [Univ. of Alberta, Edmonton, AB (Canada); Delwiche, Charles F. [Univ. of Maryland, College Park, MD (United States); Dyhrman, Sonya T. [Woods Hole Oceanographic Inst., MA (United States); Columbia Univ., Palisades, NY (United States); Glockner, Gernot [Univ. of Cologne (Germany); John, Uwe [Alfred Wegener Inst. for Polar and Marine Research, Bremerhaven (Germany); Richards, Thomas [National History Museum, London (United Kingdom); Worden, Alexandra Z. [Monterey Bay Aquarium Research Inst., Moss Landing, CA (United States); Zhang, Xiaoyu [California State Univ. (CalState), San Marcos, CA (United States); Grigoriev, Igor V. [USDOE Joint Genome Inst., Walnut Creek, CA (United States)

    2012-06-18

    Coccolithophores have influenced the global climate for over 200 million years1. These marine phytoplankton can account for 20 per cent of total carbon fixation in some systems2. They form blooms that can occupy hundreds of thousands of square kilometres and are distinguished by their elegantly sculpted calcium carbonate exoskeletons (coccoliths), rendering themvisible fromspace3.Although coccolithophores export carbon in the form of organic matter and calcite to the sea floor, they also release CO2 in the calcification process. Hence, they have a complex influence on the carbon cycle, driving either CO2 production or uptake, sequestration and export to the deep ocean4. Here we report the first haptophyte reference genome, from the coccolithophore Emiliania huxleyi strain CCMP1516, and sequences from 13 additional isolates. Our analyses reveal a pan genome (core genes plus genes distributed variably between strains) probably supported by an atypical complement of repetitive sequence in the genome. Comparisons across strains demonstrate thatE. huxleyi, which has long been considered a single species, harbours extensive genome variability reflected in different metabolic repertoires. Genome variability within this species complex seems to underpin its capacity both to thrive in habitats ranging from the equator to the subarctic and to form large-scale episodic blooms under a wide variety of environmental conditions.

  9. Postpartum depression: psychoneuroimmunological underpinnings and treatment

    Directory of Open Access Journals (Sweden)

    Anderson G

    2013-02-01

    Full Text Available George Anderson,1 Michael Maes21CRC Clincial Research Centre/Communications, Glasgow, Scotland; 2Department of Psychiatry, Chulalongkorn University, Bangkok, ThailandAbstract: Postpartum depression (PPD is common, occurring in 10%–15% of women. Due to concerns about teratogenicity of medications in the suckling infant, the treatment of PPD has often been restricted to psychotherapy. We review here the biological underpinnings to PPD, suggesting a powerful role for the tryptophan catabolites, indoleamine 2,3-dixoygenase, serotonin, and autoimmunity in mediating the consequences of immuno-inflammation and oxidative and nitrosative stress. It is suggested that the increased inflammatory potential, the decreases in endogenous anti-inflammatory compounds together with decreased omega-3 poly-unsaturated fatty acids, in the postnatal period cause an inflammatory environment. The latter may result in the utilization of peripheral inflammatory products, especially kynurenine, in driving the central processes producing postnatal depression. The pharmacological treatment of PPD is placed in this context, and recommendations for more refined and safer treatments are made, including the better utilization of the antidepressant, and the anti-inflammatory and antioxidant effects of melatonin.Keywords: SSRI, kynurenine, IDO, TDO, melatonin

  10. Scientific underpinnings of biotechnology regulatory frameworks.

    Science.gov (United States)

    Gleim, Savannah; Smyth, Stuart J

    2018-05-25

    Part of what is presently missing at domestic regulatory levels (and that is important at the international level as well) is a detailed understanding of what the rules of, and for, regulation should be, who the actors, stakeholders and major decision makers are and finally, how to get agreement about the rules. Greater insights into the system of rules that underpin regulatory frameworks for agri-food and biotechnology products in genetically modified (GM) crop- adopting nations will provide value by clarifying the evidence used to commercialize these technologies. This article examines the public documents available from Canada, the United States, the European Union and the Organisation for Economic Cooperation and Development regarding the development of regulatory risk assessment frameworks for products of biotechnology to determine what science grounds these frameworks. The documentation used to provide the initial structure to the existing regulatory frameworks identifies the linkages, connections and relationships that exist between science, risk assessment and regulatory policy. The relationship between risk and regulation has never been more critical to the commercialization of innovative agricultural products. Documenting the role of science-based risk assessment in regulations and how this has changed over the 20 years of experience in regulating GM crops will identify changes in the risk/regulation relationship. Crown Copyright © 2018. Published by Elsevier B.V. All rights reserved.

  11. Variability characteristics and comparison of Carex arenaria L. and Carex ligerica Gay populations based on rhizome characters

    Directory of Open Access Journals (Sweden)

    Lech Urbaniak

    2014-01-01

    Full Text Available The studies included 9 populations of Carex arenaria L. and 7 populations of Carex ligerica Gay, compared with each other on grounds of variability analysis, related to rhizome characters. The sedges reach in the area of Poland their eastern range limits, with isolated populations spread along the range margins. The studied plants were placed in a greenhouse in homogenous conditions,which made possible an analysis of genetic variability in the populations. The obtained results point to the absence of gene flow between the studied species and, thus, to their clearly distinct character. Genetic drift was postulated as one of the causes of the obtained variability pattern.

  12. Interpolating a consumption variable for scaling and generalizing potential population pressure on urbanizing natural areas

    Science.gov (United States)

    Varanka, Dalia; Jiang, Bin; Yao, Xiaobai

    2010-01-01

    Measures of population pressure, referring in general to the stress upon the environment by human consumption of resources, are imperative for environmental sustainability studies and management. Development based on resource consumption is the predominant factor of population pressure. This paper presents a spatial model of population pressure by linking consumption associated with regional urbanism and ecosystem services. Maps representing relative geographic degree and extent of natural resource consumption and degree and extent of impacts on surrounding areas are new, and this research represents the theoretical research toward this goal. With development, such maps offer a visualization tool for planners of various services, amenities for people, and conservation planning for ecologist. Urbanization is commonly generalized by census numbers or impervious surface area. The potential geographical extent of urbanism encompasses the environmental resources of the surrounding region that sustain cities. This extent is interpolated using kriging of a variable based on population wealth data from the U.S. Census Bureau. When overlayed with land-use/land-cover data, the results indicate that the greatest estimates of population pressure fall within mixed forest areas. Mixed forest areas result from the spread of cedar woods in previously disturbed areas where further disturbance is then suppressed. Low density areas, such as suburbanization and abandoned farmland are characteristic of mixed forest areas.

  13. Comparative performance of different stochastic methods to simulate drug exposure and variability in a population.

    Science.gov (United States)

    Tam, Vincent H; Kabbara, Samer

    2006-10-01

    Monte Carlo simulations (MCSs) are increasingly being used to predict the pharmacokinetic variability of antimicrobials in a population. However, various MCS approaches may differ in the accuracy of the predictions. We compared the performance of 3 different MCS approaches using a data set with known parameter values and dispersion. Ten concentration-time profiles were randomly generated and used to determine the best-fit parameter estimates. Three MCS methods were subsequently used to simulate the AUC(0-infinity) of the population, using the central tendency and dispersion of the following in the subject sample: 1) K and V; 2) clearance and V; 3) AUC(0-infinity). In each scenario, 10000 subject simulations were performed. Compared to true AUC(0-infinity) of the population, mean biases by various methods were 1) 58.4, 2) 380.7, and 3) 12.5 mg h L(-1), respectively. Our results suggest that the most realistic MCS approach appeared to be based on the variability of AUC(0-infinity) in the subject sample.

  14. Variability of the needle essential oils of Pinus heldreichii from different populations in Montenegro and Serbia.

    Science.gov (United States)

    Nikolić, Biljana; Ristić, Mihailo; Bojović, Srdjan; Marin, Petar D

    2007-05-01

    The essential-oil compositions of Pinus heldreichii Christ. from Montenegro and Serbia are reported at the population level. Whitebark pine is a sub-endemic high-mountain Balkan pine relict of an anthropogenically reduced area, with large morphological diversity and insufficiently clear taxonomic position. In the pine-needle terpene profile from three populations from Montenegro, and one from Serbia, 101 compounds were detected, 72 of which could be identified (Table 3). The dominant constituents are limonene (26.3%), alpha-pinene (17.5%), germacrene D (13.5%), and beta-caryophyllene (10.4%), comprising ca. 67.7% of the essential oil. Medium-to-high contents (0.5-10%) of the following 16 additional components were found: beta-pinene, beta-myrcene, alpha-humulene, delta-cadinene, alpha-muurolene, (E)-hex-2-enal, beta-gurjunene, gamma-muurolene, isopimarol, camphene, gamma-cadinene, aromadendrene, beta-bisabolene, trans-beta-farnesene, alpha-cadinene, and (Z)-hex-3-en-1-ol. The similarity of the populations and the within-population variability was visualized by principle-component analysis (PCA) of eleven selected terpenes in 97 tree samples. Cluster and genetic analyses suggest closest connection between the two spatially most-distant populations I (Montenegro) and IV (Serbia). Based on the profile of the main sesquiterpene components, the studied populations from Montenegro and Serbia are more similar to the populations from Greece and the Central Balkan peninsula (Bosnia and Serbia-Kosovo) than to those on the furthest eastern margin of their natural range (Bulgaria).

  15. GSTM1, GSTP1, and GSTT1 genetic variability in Turkish and worldwide populations.

    Science.gov (United States)

    Karaca, Sefayet; Karaca, Mehmet; Cesuroglu, Tomris; Erge, Sema; Polimanti, Renato

    2015-01-01

    Glutathione S-transferase (GST) variants have been widely investigated to better understand their role in several pathologic conditions. To our knowledge, no data about these genetic polymorphisms within the Turkish population are currently available. The aim of this study was to analyze GSTM1 positive/null, GSTT1 positive/null, GSTP1*I105V (rs1695), and GSTP1*A114V (rs1138272) variants in the general Turkish population, to provide information about its genetic diversity, and predisposition to GST-related diseases. Genotyping was performed in 500 Turkish individuals using the Sequenom MassARRAY platform. A comparative analysis was executed using the data from the HapMap and Human Genome Diversity Projects (HGDP). Sequence variation was deeply explored using the Phase 1 data of the 1,000 Genomes Project. The variability of GSTM1, GSTT1, and GSTP1 polymorphisms in the Turkish population was similar to that observed in Central Asian, European, and Middle Eastern populations. The high linkage disequilibrium between GSTP1*I105V and GSTP1*A114V in these populations may have a confounding effect on GSTP1 genetic association studies. In analyzing GSTM1, GSTT1, and GSTP1 sequence variation, we observed other common functional variants that may be candidates for associated studies of diseases related to GST genes (e.g., cancer, cardiovascular disease, and allergy). This study provides novel data about GSTM1 positive/null, GSTT1 positive/null, GSTP1*I105V, and GSTP1*A114V variants in the Turkish population, and other functional variants that may affect GSTM1, GSTT1, and GSTP1 functions among worldwide populations. This information can assist in the design of future genetic association studies investigating oxidative stress-related diseases. © 2014 Wiley Periodicals, Inc.

  16. Cellular and circuit mechanisms maintain low spike co-variability and enhance population coding in somatosensory cortex

    Directory of Open Access Journals (Sweden)

    Cheng eLy

    2012-03-01

    Full Text Available The responses of cortical neurons are highly variable across repeated presentations of a stimulus. Understanding this variability is critical for theories of both sensory and motor processing, since response variance affects the accuracy of neural codes. Despite this influence, the cellular and circuit mechanisms that shape the trial-to-trial variability of population responses remain poorly understood. We used a combination of experimental and computational techniques to uncover the mechanisms underlying response variability of populations of pyramidal (E cells in layer 2/3 of rat whisker barrel cortex. Spike trains recorded from pairs of E-cells during either spontaneous activity or whisker deflected responses show similarly low levels of spiking co-variability, despite large differences in network activation between the two states. We developed network models that show how spike threshold nonlinearities dilutes E-cell spiking co-variability during spontaneous activity and low velocity whisker deflections. In contrast, during high velocity whisker deflections, cancelation mechanisms mediated by feedforward inhibition maintain low E-cell pairwise co-variability. Thus, the combination of these two mechanisms ensure low E-cell population variability over a wide range of whisker deflection velocities. Finally, we show how this active decorrelation of population variability leads to a drastic increase in the population information about whisker velocity. The canonical cellular and circuit components of our study suggest that low network variability over a broad range of neural states may generalize across the nervous system.

  17. Topological variability and sex differences in fingerprint ridge density in a sample of the Sudanese population.

    Science.gov (United States)

    Ahmed, Altayeb Abdalla; Osman, Samah

    2016-08-01

    Fingerprints are important biometric variables that show manifold utilities in human biology, human morphology, anthropology, and genetics. Their role in forensics as a legally admissible tool of identification is well recognized and is based on their stability following full development, individualistic characteristics, easy classification of their patterns, and uniqueness. Nevertheless, fingerprint ridge density and its variability have not been previously studied in the Sudanese population. Hence, this study was conducted to analyze the topological variability in epidermal ridge density and to assess the possibility of its application in determining sex of Sudanese Arabs. The data used for this study were prints of all 10 fingers of 200 Sudanese Arab individuals (100 men and 100 women) aged between 18 and 28 years. Fingerprint ridge density was assessed for three different areas (radial, ulnar and proximal) for all 10 fingers of each subject. Significant variability was found between the areas (p crime scenes can be useful to determine sex of Sudanese individuals based on fingerprint ridge density; furthermore, ridge density can be considered a morphological trait for individual variation in forensic anthropology. Copyright © 2016 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  18. Flares of Orion population variables in the association Taurus T3

    International Nuclear Information System (INIS)

    Khodzhaev, A.S.; AN Armyanskoj SSR, Byurakan. Astrofizicheskaya Observatoriya)

    1987-01-01

    Thirteen new flare stars, proved to be irregular variables of Orion Population, were discovered from a study of the Taurus Dark Cloud region by the homogeneous photographic multipose method on the wide angle Schmidt telescopes of the Byurakan Astorphysical Observatory. Seventeen flares on these stars were detected for about 750 hours of the effective observing time. The analysis of the complicated light curves of these flares shows a great variety and multiplicity of this phenomenon and various dynamics of flare energy release processes. The existence of flare stars with some properties typical for both of the T Tauri and UV Ceti stars simulteneously indicates nonstable stars. The population of flare stars in the Taurus Dark Cloud region is apparently as young as in Orion and Monoceros

  19. Predicting farm-level animal populations using environmental and socioeconomic variables.

    Science.gov (United States)

    van Andel, Mary; Jewell, Christopher; McKenzie, Joanna; Hollings, Tracey; Robinson, Andrew; Burgman, Mark; Bingham, Paul; Carpenter, Tim

    2017-09-15

    Accurate information on the geographic distribution of domestic animal populations helps biosecurity authorities to efficiently prepare for and rapidly eradicate exotic diseases, such as Foot and Mouth Disease (FMD). Developing and maintaining sufficiently high-quality data resources is expensive and time consuming. Statistical modelling of population density and distribution has only begun to be applied to farm animal populations, although it is commonly used in wildlife ecology. We developed zero-inflated Poisson regression models in a Bayesian framework using environmental and socioeconomic variables to predict the counts of livestock units (LSUs) and of cattle on spatially referenced farm polygons in a commercially available New Zealand farm database, Agribase. Farm-level counts of cattle and of LSUs varied considerably by region, because of the heterogeneous farming landscape in New Zealand. The amount of high quality pasture per farm was significantly associated with the presence of both cattle and LSUs. Internal model validation (predictive performance) showed that the models were able to predict the count of the animal population on groups of farms that were located in randomly selected 3km zones with a high level of accuracy. Predicting cattle or LSU counts on individual farms was less accurate. Predicted counts were statistically significantly more variable for farms that were contract grazing dry stock, such as replacement dairy heifers and dairy cattle not currently producing milk, compared with other farm types. This analysis presents a way to predict numbers of LSUs and cattle for farms using environmental and socio-economic data. The technique has the potential to be extrapolated to predicting other pastoral based livestock species. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Impacts of environmental variability on desiccation rate, plastic responses and population dynamics of Glossina pallidipes.

    Science.gov (United States)

    Kleynhans, E; Clusella-Trullas, S; Terblanche, J S

    2014-02-01

    Physiological responses to transient conditions may result in costly responses with little fitness benefits, and therefore, a trade-off must exist between the speed of response and the duration of exposure to new conditions. Here, using the puparia of an important insect disease vector, Glossina pallidipes, we examine this potential trade-off using a novel combination of an experimental approach and a population dynamics model. Specifically, we explore and dissect the interactions between plastic physiological responses, treatment-duration and -intensity using an experimental approach. We then integrate these experimental results from organismal water-balance data and their plastic responses into a population dynamics model to examine the potential relative fitness effects of simulated transient weather conditions on population growth rates. The results show evidence for the predicted trade-off for plasticity of water loss rate (WLR) and the duration of new environmental conditions. When altered environmental conditions lasted for longer durations, physiological responses could match the new environmental conditions, and this resulted in a lower WLR and lower rates of population decline. At shorter time-scales however, a mismatch between acclimation duration and physiological responses was reflected by reduced overall population growth rates. This may indicate a potential fitness cost due to insufficient time for physiological adjustments to take place. The outcomes of this work therefore suggest plastic water balance responses have both costs and benefits, and these depend on the time-scale and magnitude of variation in environmental conditions. These results are significant for understanding the evolution of plastic physiological responses and changes in population abundance in the context of environmental variability. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

  1. Mixing times towards demographic equilibrium in insect populations with temperature variable age structures.

    Science.gov (United States)

    Damos, Petros

    2015-08-01

    In this study, we use entropy related mixing rate modules to measure the effects of temperature on insect population stability and demographic breakdown. The uncertainty in the age of the mother of a randomly chosen newborn, and how it is moved after a finite act of time steps, is modeled using a stochastic transformation of the Leslie matrix. Age classes are represented as a cycle graph and its transitions towards the stable age distribution are brought forth as an exact Markov chain. The dynamics of divergence, from a non equilibrium state towards equilibrium, are evaluated using the Kolmogorov-Sinai entropy. Moreover, Kullback-Leibler distance is applied as information-theoretic measure to estimate exact mixing times of age transitions probabilities towards equilibrium. Using empirically data, we show that on the initial conditions and simulated projection's trough time, that population entropy can effectively be applied to detect demographic variability towards equilibrium under different temperature conditions. Changes in entropy are correlated with the fluctuations of the insect population decay rates (i.e. demographic stability towards equilibrium). Moreover, shorter mixing times are directly linked to lower entropy rates and vice versa. This may be linked to the properties of the insect model system, which in contrast to warm blooded animals has the ability to greatly change its metabolic and demographic rates. Moreover, population entropy and the related distance measures that are applied, provide a means to measure these rates. The current results and model projections provide clear biological evidence why dynamic population entropy may be useful to measure population stability. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Essential-Oil Variability in Natural Populations of Pinus mugo Turra from the Julian Alps.

    Science.gov (United States)

    Bojović, Srdjan; Jurc, Maja; Ristić, Mihailo; Popović, Zorica; Matić, Rada; Vidaković, Vera; Stefanović, Milena; Jurc, Dušan

    2016-02-01

    The composition and variability of the terpenes and their derivatives isolated from the needles of a representative pool of 114 adult trees originating from four natural populations of dwarf mountain pine (Pinus mugo Turra) from the Julian Alps were investigated by GC-FID and GC/MS analyses. In total, 54 of the 57 detected essential-oil components were identified. Among the different compound classes present in the essential oils, the chief constituents belonged to the monoterpenes, comprising an average content of 79.67% of the total oil composition (74.80% of monoterpene hydrocarbons and 4.87% of oxygenated monoterpenes). Sesquiterpenes were present in smaller amounts (average content of 19.02%), out of which 16.39% were sesquiterpene hydrocarbons and 2.62% oxygenated sesquiterpenes. The most abundant components in the needle essential oils were the monoterpenes δ-car-3-ene, β-phellandrene, α-pinene, β-myrcene, and β-pinene and the sesquiterpene β-caryophyllene. From the total data set of 57 detected compounds, 40 were selected for principal-component analysis (PCA), discriminant analysis (DA), and cluster analysis (CA). The overlap tendency of the four populations suggested by PCA, was as well observed by DA. CA also demonstrated similarity among the populations, which was the highest between Populations I and II. Copyright © 2016 Verlag Helvetica Chimica Acta AG, Zürich.

  3. Genetic variability of CYP2B6 polymorphisms in four southern Chinese populations

    Science.gov (United States)

    Xu, Bing-Ying; Guo, Li-Ping; Lee, Shui-Shan; Dong, Qing-Ming; Tan, Yi; Yao, Hong; Li, Li-Hua; Lin, Che-Kit; Kung, Hsiang-Fu; He, Ming-Liang

    2007-01-01

    AIM: To investigate the genotype and allelic frequencies of Cytochrome P450 2B6 polymorphisms in four southern Chinese populations. METHODS: DNA was obtained from blood samples from Han Chinese from Hong Kong and three minority groups, the Wa, Bulang and Lahu from Yunnan in southern China. Genotyping was performed using real-time PCR and confirmed by direct sequencing. RESULTS: A total of 507 subjects from southern China were studied. Results showed there is a high prevalence of 516G > T (34.5%) in ethnic Chinese compared to literature reports on other Asian populations and Caucasians. The frequency of the 516TT genotype is higher in the Han majority (23.1%) than in three other ethnic minority groups (i.e., 7.4%, 9.1% and 15.8%) in southern China. CONCLUSION: This was the first study to document the spectrum of CYP2B6 allelic variants and genotypes in a southern Chinese population. The 516G > T allele is associated with a defective metabolism of efavirenz (EFV), which therefore may predispose to drug toxicity. Treatment regimens for human immunodeficiency virus (HIV) and heroin addiction may need to be optimized in different populations because of the marked variability of the key metabolizing enzyme. PMID:17465455

  4. HLA-E regulatory and coding region variability and haplotypes in a Brazilian population sample.

    Science.gov (United States)

    Ramalho, Jaqueline; Veiga-Castelli, Luciana C; Donadi, Eduardo A; Mendes-Junior, Celso T; Castelli, Erick C

    2017-11-01

    The HLA-E gene is characterized by low but wide expression on different tissues. HLA-E is considered a conserved gene, being one of the least polymorphic class I HLA genes. The HLA-E molecule interacts with Natural Killer cell receptors and T lymphocytes receptors, and might activate or inhibit immune responses depending on the peptide associated with HLA-E and with which receptors HLA-E interacts to. Variable sites within the HLA-E regulatory and coding segments may influence the gene function by modifying its expression pattern or encoded molecule, thus, influencing its interaction with receptors and the peptide. Here we propose an approach to evaluate the gene structure, haplotype pattern and the complete HLA-E variability, including regulatory (promoter and 3'UTR) and coding segments (with introns), by using massively parallel sequencing. We investigated the variability of 420 samples from a very admixed population such as Brazilians by using this approach. Considering a segment of about 7kb, 63 variable sites were detected, arranged into 75 extended haplotypes. We detected 37 different promoter sequences (but few frequent ones), 27 different coding sequences (15 representing new HLA-E alleles) and 12 haplotypes at the 3'UTR segment, two of them presenting a summed frequency of 90%. Despite the number of coding alleles, they encode mainly two different full-length molecules, known as E*01:01 and E*01:03, which corresponds to about 90% of all. In addition, differently from what has been previously observed for other non classical HLA genes, the relationship among the HLA-E promoter, coding and 3'UTR haplotypes is not straightforward because the same promoter and 3'UTR haplotypes were many times associated with different HLA-E coding haplotypes. This data reinforces the presence of only two main full-length HLA-E molecules encoded by the many HLA-E alleles detected in our population sample. In addition, this data does indicate that the distal HLA-E promoter is by

  5. The influence of climatic variability on local population dynamics of Cercidium microphyllum (foothill paloverde)

    Science.gov (United States)

    Bowers, Janice E.; Turner, R.M.

    2002-01-01

    This study investigated correlations among climatic variability, population age structure, and seedling survival of a dominant Sonoran Desert tree, Cercidium microphyllum (foothill paloverde), at Tucson, Arizona, USA. A major goal was to determine whether wet years promote seedling establishment and thereby determine population structure. Plant age was estimated from basal circumference for a sample of 980 living and dead trees in twelve 0.5-ha plots. Ages ranged from 1 to 181 years. Age frequency distribution showed that the population is in decline. Most (51.2%) of the 814 living trees were 40-80 years old; only 6.5% were younger than 20 years. The average age of the 166 dead trees was 78 years. Fifty-nine percent of dead trees were aged 60-100 years. Survival of newly emerged seedlings was monitored for 7 years in a 557-m2 permanent plot. Mean survival in the 1st year of life was 1.7%. Only 2 of 1,008 seedlings lived longer than 1 year. Length of survival was not correlated with rainfall. Residual regeneration, an index of the difference between predicted and observed cohort size, showed that regeneration was high during the first half of the twentieth century and poor after the mid-1950s. Trends in regeneration did not reflect interannual variation in seasonal temperature or rain before 1950, that is, in the years before urban warming. Taken together, the seedling study and the regeneration analysis suggest that local population dynamics reflect biotic factors to such an extent that population age structure might not always be a reliable clue to past climatic influences.

  6. [Study of obesity in a rural children population and its relationship with anthropometric variables].

    Science.gov (United States)

    Vaquero-Álvarez, Manuel; Romero-Saldaña, Manuel; Valle-Alonso, Joaquin; Llorente Cantarero, Francisco Jesús; Blancas-Sánchez, Isabel María; Fonseca Del Pozo, Francisco Javier

    2018-05-19

    To know the prevalence of obesity in primary and secondary school students, and to evaluate the diagnostic accuracy of anthropometric variables for its detection. Cross-sectional study. Rural area of Córdoba. In the year 2014. Student population. A stratified sampling was performed according to age, gender and educational centers. A total of 323 students from 6 to 16 years were included in the study, all parents had signed informed consent. The prevalence of obesity was determined and sociodemographic, anthropometric, physical condition and dietary predictor variables were collected. A binary logistic regression was performed determining crude and adjusted Odds Ratio (OR) values, ROC curves were obtained and cut-off values were determined, calculating the sensitivity, specificity and Youden index. The prevalence of overweight and obesity was 26.2% and 22.3%, respectively. Only 15.2% of school children had an optimal Mediterranean diet. The waist-height ratio (WtHR) was the predictive variable with the highest adjusted OR 7.1 (4.3-11.6) and the largest area under the curve 0.954 (0.928-0.979), from a global cut-off value to discriminate obesity of 0.507. This gave a sensitivity of 90% and specificity of 87.2%. The high prevalence of obesity, the low-medium adherence to the Mediterranean diet and the low physical fitness make this population a priority target for the prevention of future cardiovascular events. The WtHR has been the best anthropometric predictor of obesity, recommending its use for the diagnosis of obesity in children at the expense of body mass index. Copyright © 2018 The Authors. Publicado por Elsevier España, S.L.U. All rights reserved.

  7. Local Variability Mediates Vulnerability of Trout Populations to Land Use and Climate Change.

    Directory of Open Access Journals (Sweden)

    Brooke E Penaluna

    Full Text Available Land use and climate change occur simultaneously around the globe. Fully understanding their separate and combined effects requires a mechanistic understanding at the local scale where their effects are ultimately realized. Here we applied an individual-based model of fish population dynamics to evaluate the role of local stream variability in modifying responses of Coastal Cutthroat Trout (Oncorhynchus clarkii clarkii to scenarios simulating identical changes in temperature and stream flows linked to forest harvest, climate change, and their combined effects over six decades. We parameterized the model for four neighboring streams located in a forested headwater catchment in northwestern Oregon, USA with multi-year, daily measurements of stream temperature, flow, and turbidity (2007-2011, and field measurements of both instream habitat structure and three years of annual trout population estimates. Model simulations revealed that variability in habitat conditions among streams (depth, available habitat mediated the effects of forest harvest and climate change. Net effects for most simulated trout responses were different from or less than the sum of their separate scenarios. In some cases, forest harvest countered the effects of climate change through increased summer flow. Climate change most strongly influenced trout (earlier fry emergence, reductions in biomass of older trout, increased biomass of young-of-year, but these changes did not consistently translate into reductions in biomass over time. Forest harvest, in contrast, produced fewer and less consistent responses in trout. Earlier fry emergence driven by climate change was the most consistent simulated response, whereas survival, growth, and biomass were inconsistent. Overall our findings indicate a host of local processes can strongly influence how populations respond to broad scale effects of land use and climate change.

  8. A NEW MODIFIED RATIO ESTIMATOR FOR ESTIMATION OF POPULATION MEAN WHEN MEDIAN OF THE AUXILIARY VARIABLE IS KNOWN

    Directory of Open Access Journals (Sweden)

    Jambulingam Subramani

    2013-10-01

    Full Text Available The present paper deals with a modified ratio estimator for estimation of population mean of the study variable when the population median of the auxiliary variable is known. The bias and mean squared error of the proposed estimator are derived and are compared with that of existing modified ratio estimators for certain known populations. Further we have also derived the conditions for which the proposed estimator performs better than the existing modified ratio estimators. From the numerical study it is also observed that the proposed modified ratio estimator performs better than the existing modified ratio estimators for certain known populations.

  9. Variable population exposure and distributed travel speeds in least-cost tsunami evacuation modelling

    Science.gov (United States)

    Fraser, Stuart A.; Wood, Nathan J.; Johnston, David A.; Leonard, Graham S.; Greening, Paul D.; Rossetto, Tiziana

    2014-01-01

    Evacuation of the population from a tsunami hazard zone is vital to reduce life-loss due to inundation. Geospatial least-cost distance modelling provides one approach to assessing tsunami evacuation potential. Previous models have generally used two static exposure scenarios and fixed travel speeds to represent population movement. Some analyses have assumed immediate departure or a common evacuation departure time for all exposed population. Here, a method is proposed to incorporate time-variable exposure, distributed travel speeds, and uncertain evacuation departure time into an existing anisotropic least-cost path distance framework. The method is demonstrated for hypothetical local-source tsunami evacuation in Napier City, Hawke's Bay, New Zealand. There is significant diurnal variation in pedestrian evacuation potential at the suburb level, although the total number of people unable to evacuate is stable across all scenarios. Whilst some fixed travel speeds approximate a distributed speed approach, others may overestimate evacuation potential. The impact of evacuation departure time is a significant contributor to total evacuation time. This method improves least-cost modelling of evacuation dynamics for evacuation planning, casualty modelling, and development of emergency response training scenarios. However, it requires detailed exposure data, which may preclude its use in many situations.

  10. Variability in permanent tooth size of three ancient populations in Xi'an, northern China.

    Science.gov (United States)

    Huang, Shi-You; Kang, Ting; Liu, Dai-Yun; Duan, Yin-Zhong; Shao, Jin-Ling

    2012-11-01

    This paper compares permanent dental dimensions between three ancient populations that belonged to the same biological population throughout a temporal range of 2000 years to detect temporal trends and metric variation in dentition. The samples analysed were dental remains of 4502 permanent teeth from 321 individuals, which were excavated from three archaeological sites: Chang'an (1000-1300 years BP), Shanren (2200 years BP) and Shaolingyuan (3000 years BP) in the Xi'an region (northern China). For each tooth three standard measurements were taken: Mesiodistal (MD) diameter of crown, labiolingual or buccolingual (BL) diameter of crown and length of root (LR). Three ancient population samples generally displayed the same dental dimensions (p>0.05), whereas some tooth types varied. The Shaolingyuan had larger canine and the smallest maxillary second molars and the Chang'an had the largest mandibular first molars in the MD dimension. The Shanren had the smallest maxillary third molars and mandibular central incisors, and the Chang'an had the smallest maxillary lateral incisors in the BL dimension. In the LR measures, statistically significant differences of five tooth types showed that the Chang'an were smaller than the Shaolingyuan and the Shanren. Comparisons of coefficients of variation for teeth showed that the length of root and third molar usually displayed greater variation. Decreasing or increasing trend for crown size does not occur between the ancient populations, while changes in crown size of a few tooth types fluctuate. The root size is more variable than the crown size and is likely to reflect a degenerated trend in a few tooth types. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. The neural underpinnings of music listening under different attention conditions.

    Science.gov (United States)

    Jäncke, Lutz; Leipold, Simon; Burkhard, Anja

    2018-05-02

    Most studies examining the neural underpinnings of music listening have no specific instruction on how to process the presented musical pieces. In this study, we explicitly manipulated the participants' focus of attention while they listened to the musical pieces. We used an ecologically valid experimental setting by presenting the musical stimuli simultaneously with naturalistic film sequences. In one condition, the participants were instructed to focus their attention on the musical piece (attentive listening), whereas in the second condition, the participants directed their attention to the film sequence (passive listening). We used two instrumental musical pieces: an electronic pop song, which was a major hit at the time of testing, and a classical musical piece. During music presentation, we measured electroencephalographic oscillations and responses from the autonomic nervous system (heart rate and high-frequency heart rate variability). During passive listening to the pop song, we found strong event-related synchronizations in all analyzed frequency bands (theta, lower alpha, upper alpha, lower beta, and upper beta). The neurophysiological responses during attentive listening to the pop song were similar to those of the classical musical piece during both listening conditions. Thus, the focus of attention had a strong influence on the neurophysiological responses to the pop song, but not on the responses to the classical musical piece. The electroencephalographic responses during passive listening to the pop song are interpreted as a neurophysiological and psychological state typically observed when the participants are 'drawn into the music'.

  12. Environmental forcing and Southern Ocean marine predator populations: effects of climate change and variability.

    Science.gov (United States)

    Trathan, P N; Forcada, J; Murphy, E J

    2007-12-29

    The Southern Ocean is a major component within the global ocean and climate system and potentially the location where the most rapid climate change is most likely to happen, particularly in the high-latitude polar regions. In these regions, even small temperature changes can potentially lead to major environmental perturbations. Climate change is likely to be regional and may be expressed in various ways, including alterations to climate and weather patterns across a variety of time-scales that include changes to the long interdecadal background signals such as the development of the El Niño-Southern Oscillation (ENSO). Oscillating climate signals such as ENSO potentially provide a unique opportunity to explore how biological communities respond to change. This approach is based on the premise that biological responses to shorter-term sub-decadal climate variability signals are potentially the best predictor of biological responses over longer time-scales. Around the Southern Ocean, marine predator populations show periodicity in breeding performance and productivity, with relationships with the environment driven by physical forcing from the ENSO region in the Pacific. Wherever examined, these relationships are congruent with mid-trophic-level processes that are also correlated with environmental variability. The short-term changes to ecosystem structure and function observed during ENSO events herald potential long-term changes that may ensue following regional climate change. For example, in the South Atlantic, failure of Antarctic krill recruitment will inevitably foreshadow recruitment failures in a range of higher trophic-level marine predators. Where predator species are not able to accommodate by switching to other prey species, population-level changes will follow. The Southern Ocean, though oceanographically interconnected, is not a single ecosystem and different areas are dominated by different food webs. Where species occupy different positions in

  13. Environmental variability uncovers disruptive effects of species' interactions on population dynamics.

    Science.gov (United States)

    Gudmundson, Sara; Eklöf, Anna; Wennergren, Uno

    2015-08-07

    How species respond to changes in environmental variability has been shown for single species, but the question remains whether these results are transferable to species when incorporated in ecological communities. Here, we address this issue by analysing the same species exposed to a range of environmental variabilities when (i) isolated or (ii) embedded in a food web. We find that all species in food webs exposed to temporally uncorrelated environments (white noise) show the same type of dynamics as isolated species, whereas species in food webs exposed to positively autocorrelated environments (red noise) can respond completely differently compared with isolated species. This is owing to species following their equilibrium densities in a positively autocorrelated environment that in turn enables species-species interactions to come into play. Our results give new insights into species' response to environmental variation. They especially highlight the importance of considering both species' interactions and environmental autocorrelation when studying population dynamics in a fluctuating environment. © 2015 The Author(s).

  14. Gradual plasticity alters population dynamics in variable environments: thermal acclimation in the green alga Chlamydomonas reinhartdii.

    Science.gov (United States)

    Kremer, Colin T; Fey, Samuel B; Arellano, Aldo A; Vasseur, David A

    2018-01-10

    Environmental variability is ubiquitous, but its effects on populations are not fully understood or predictable. Recent attention has focused on how rapid evolution can impact ecological dynamics via adaptive trait change. However, the impact of trait change arising from plastic responses has received less attention, and is often assumed to optimize performance and unfold on a separate, faster timescale than ecological dynamics. Challenging these assumptions, we propose that gradual plasticity is important for ecological dynamics, and present a study of the plastic responses of the freshwater green algae Chlamydomonas reinhardtii as it acclimates to temperature changes. First, we show that C. reinhardtii 's gradual acclimation responses can both enhance and suppress its performance after a perturbation, depending on its prior thermal history. Second, we demonstrate that where conventional approaches fail to predict the population dynamics of C. reinhardtii exposed to temperature fluctuations, a new model of gradual acclimation succeeds. Finally, using high-resolution data, we show that phytoplankton in lake ecosystems can experience thermal variation sufficient to make acclimation relevant. These results challenge prevailing assumptions about plasticity's interactions with ecological dynamics. Amidst the current emphasis on rapid evolution, it is critical that we also develop predictive methods accounting for plasticity. © 2018 The Author(s).

  15. Variables associated with olfactory disorders in adults: A U.S. population-based analysis

    Directory of Open Access Journals (Sweden)

    Julia Noel

    2017-03-01

    Full Text Available Objective: Olfactory dysfunction is known to have significant social, psychological, and safety implications. Despite increasingly recognized prevalence, potential risk factors for olfactory loss have been arbitrarily documented and knowledge is limited in scale. The aim of this study is to identify potential demographic and exposure variables correlating with olfactory dysfunction. Methods: Cross-sectional analysis of the 2011–2012 and 2013–2014 editions of the National Health Examination and Nutrition Survey was performed. The utilized survey reports from a nationally representative sample of about 5000 persons each year located in counties across the United States. There is an interview and physical examination component which includes demographic, socioeconomic, dietary, and health-related questions as well as medical, dental, physiologic measurements, and laboratory tests. 3594 adult respondents from 2011 to 2012 and 3708 respondents from 2013 to 2014 were identified from the above population-based database. The frequency of self-reported disorders as well as performance on odor identification testing was determined in relation to demographic factors, occupational or environmental exposures, and urinary levels of environmental and industrial compounds. Results: In both subjective and objective analysis, smell disorders were significantly more common with increasing age. While the non-Hispanic Black and non-Hispanic Asian populations were less likely to report subjective olfactory loss, they, along with Hispanics, performed more poorly on odor identification than Caucasians. Those with limited education had a decreased prevalence of hyposmia. Women outperformed men on smell testing. Those reporting exposure to vapors were more likely to experience olfactory dysfunction, and urinary levels of manganese, 2-Thioxothiazolidine-4-carboxylic acid, and 2-Aminothiazoline-4-carboxylic acid were lower among respondents with subjective smell

  16. Essential oil composition variability among natural populations of Pinus mugo Turra in Kosovo.

    Science.gov (United States)

    Hajdari, Avni; Mustafa, Behxhet; Ahmeti, Gresa; Pulaj, Bledar; Lukas, Brigitte; Ibraliu, Alban; Stefkov, Gjoshe; Quave, Cassandra L; Novak, Johannes

    2015-01-01

    Pinus mugo Turra, is a native pine species in central and southern Europe, growing in high mountains area (altitudes 1.800-2.300 m.a.s.l.). In Kosovo, it is one of the native pines too, distributed in high altitudes in the Sharri Mountains and Albanian Alps Mountains. Its populations represent an important wealth of essential oil resources available, which make this species very important in terms of economic values. The chemical composition and yields of the essential oils of dwarf pine (Pinus mugo Turra) needles, twigs and cones from six wild populations in Kosovo were investigated with the aim to assess their natural variability. The identity of P. mugo was confirmed by morphology and DNA barcoding. Sixty-two compounds were identified representing 69-95 % of the total identified compounds. The yield ranged from 0.3-0.8 % v/w in needles, 1.0-2.4 % v/w in twigs and 0.1-0.5 % v/w in cones, depending on the origin of plant material and plant organs. α-Pinene (needles: 16.9-24.5 %; twigs: 4.5-8.8 %; cones: 3.1-5.6 %), β-pinene (needles: 1.5-5.4 %; twigs: 2.2-15.4 %; cones: 1.3-14.2 %), δ-3-carene (needles: 15.4-27.8 %; twigs: 24.0-51.6 %; cones: 10.5-31.5 %), limonene + β-phellandrene (needles: 1.9-5.9 %; twigs: 12.6-24.2 %; cones: 2.1-9.3 %), (E)-caryophyllene (needles: 4.4-8.9 %; twigs: 4.0-10.8 %; cones: 10.3-26.9 %) and germacrene D (needles: 4.0-8.3 %; twigs: 0.2-6.19 %; cones: 0.1-12.4 %) were the major components of the essential oil. Principal component analysis (PCA) and hierarchical cluster analyses (HCA) suggests that the population of P. mugo clustering is not related to their geographic location, but rather seemed to be linked to local selective forces acting on chemotype diversity. Low variability related to their geographic location has an economic importance since samples originating from different locations in Kosovo can treated with same standards.

  17. Inter- and intra-population genetic variability of introduced silkworm (Bombyx mori L. strains raised in Bulgaria

    Directory of Open Access Journals (Sweden)

    Teodora Staykova

    2013-01-01

    Full Text Available The genetic variability of four populations belonging to two introduced silkworm strains (Bombyx mori L. of various origins has been studied using isoenzymic analysis of six enzyme systems. Nonspecific esterases, phosphoglucomutase, malate dehydrogenase, acid phosphatase, alkaline phosphatase and hexokinase from different tissue of larvae 5th instar have been analysed using PAGE. Polymorphism in six from a total of nine loci has been found. Inter- and intra-population differences have been ascertained expressed in different allele composition of the gene pool and different frequencies of alleles. A higher degree of inter-population variability has been reported on the acid phosphatase and a lower one – on the phosphoglucomutase.

  18. A highly variable segment of human subterminal 16p reveals a history of population growth for modern humans outside Africa

    Science.gov (United States)

    Alonso, Santos; Armour, John A. L.

    2001-01-01

    We have sequenced a highly polymorphic subterminal noncoding region from human chromosome 16p13.3, flanking the 5′ end of the hypervariable minisatellite MS205, in 100 chromosomes sampled from different African and Euroasiatic populations. Coalescence analysis indicates that the time to the most recent common ancestor (approximately 1 million years) predates the appearance of anatomically modern human forms. The root of the network describing this variability lies in Africa. African populations show a greater level of diversity and deeper branches. Most Euroasiatic variability seems to have been generated after a recent out-of-Africa range expansion. A history of population growth is the most likely scenario for the Euroasiatic populations. This pattern of nuclear variability can be reconciled with inferences based on mitochondrial DNA. PMID:11158547

  19. Eyes to See: The Foothold of Jihadi Underpinnings

    National Research Council Canada - National Science Library

    Klein, Jr, John M

    2007-01-01

    .... These underpinnings are well-established and rigorously authenticated precepts that serve as a foothold for Jihadi conduct, making Islam a ready-made ideology that suits the Jihadis' insatiable goals...

  20. Population growth rate and genetic variability of small and large populations of Red flour beetle (Tribolium castaneum) following multigenerational exposure to copper.

    Science.gov (United States)

    Laskowski, Ryszard; Radwan, Jacek; Kuduk, Katarzyna; Mendrok, Magdalena; Kramarz, Paulina

    2015-07-01

    We reared large (1000 individuals) and small (20 individuals) populations of Tribolium castaneum on diet contaminated with copper in order to determine if the size of a population affects its ability to adapt to adverse environmental conditions. After 10 generations, we used microsatellite markers to estimate and subsequently compare the genetic variability of the copper-treated populations with that of the control populations, which were reared on uncontaminated medium. Additionally, we conducted a full cross-factorial experiment which evaluated the effects of 10 generations of "pre-exposure" to copper on a population's fitness in control and copper-contaminated environments. In order to distinguish results potentially arising from genetic adaptation from those due to non-genetic effects associated to parental exposure to copper, we subjected also F11 generation, originating from parents not exposed to copper, to the same cross-factorial experiment. The effects of long-term exposure to copper depended on population size: the growth rates of small populations that were pre-exposed to copper were inhibited compared to those of small populations reared in uncontaminated environments. Large Cu-exposed populations had a higher growth rate in the F10 generation compared to the control groups, while the growth rate of the F11 generation was unaffected by copper exposure history. The only factor that had a significant effect on genetic variability was population size, but this was to be expected given the large difference in the number of individuals between large and small populations. Neither copper contamination nor its interaction with population size affected the number of microsatellite alleles retained in the F10 generation.

  1. Dwarf spheroidal satellites of M31. I. Variable stars and stellar populations in Andromeda XIX

    Energy Technology Data Exchange (ETDEWEB)

    Cusano, Felice; Clementini, Gisella; Garofalo, Alessia; Federici, Luciana, E-mail: felice.cusano@oabo.inaf.it, E-mail: gisella.clementini@oabo.inaf.it, E-mail: luciana.federici@oabo.inaf.it, E-mail: alessia.garofalo@studio.unibo.it [INAF-Osservatorio Astronomico di Bologna, Via Ranzani 1, I-40127 Bologna (Italy); and others

    2013-12-10

    We present B, V time-series photometry of Andromeda XIX (And XIX), the most extended (half-light radius of 6.'2) of Andromeda's dwarf spheroidal companions, which we observed with the Large Binocular Cameras at the Large Binocular Telescope. We surveyed a 23' × 23' area centered on And XIX and present the deepest color-magnitude diagram (CMD) ever obtained for this galaxy, reaching, at V ∼ 26.3 mag, about one magnitude below the horizontal branch (HB). The CMD shows a prominent and slightly widened red giant branch, along with a predominantly red HB, which extends to the blue to significantly populate the classical instability strip. We have identified 39 pulsating variable stars, of which 31 are of RR Lyrae type and 8 are Anomalous Cepheids (ACs). Twelve of the RR Lyrae variables and three of the ACs are located within And XIX's half light radius. The average period of the fundamental mode RR Lyrae stars ((P {sub ab}) = 0.62 days, σ = 0.03 days) and the period-amplitude diagram qualify And XIX as an Oosterhoff-Intermediate system. From the average luminosity of the RR Lyrae stars ((V(RR)) = 25.34 mag, σ = 0.10 mag), we determine a distance modulus of (m – M){sub 0} = 24.52 ± 0.23 mag in a scale where the distance to the Large Magellanic Cloud (LMC) is 18.5 ± 0.1 mag. The ACs follow a well-defined Period-Wesenheit (PW) relation that appears to be in very good agreement with the PW relationship defined by the ACs in the LMC.

  2. Sociocultural variability in the Latino population: Age patterns and differences in morbidity among older US adults

    Directory of Open Access Journals (Sweden)

    Catherine Garcia

    2018-05-01

    Full Text Available Background: The US Latino population is rapidly aging and becoming increasingly diverse with respect to nativity and national origin. Increased longevity along with medical advancements in treatment have resulted in a higher number of older Latinos living with morbidity. Therefore, there is a need to understand variability in Latino health among older adults. Objective: This paper documents mid- and late-life health differences in morbidity by race/ethnicity, nativity, and country of origin among adults aged 50 and older. Methods: We use data from the 2000-2015 National Health Interview Survey to calculate age- and gender-specific proportions based on reports of five morbidity measures: hypertension, heart disease, stroke, cancer, and diabetes among non-Latino Whites and seven Latino subgroups. Results: The foreign-born from Mexico, Cuba, and Central/South America, regardless of gender, exhibit an immigrant advantage for heart disease and cancer in comparison to non-Latino Whites across all age categories. Conversely, island-born Puerto Ricans are generally characterized with higher levels of morbidity. Similarly, US-born Puerto Ricans and Mexicans exhibit morbidity patterns indicative of their minority status. Latinos, regardless of gender, were more likely to report diabetes than non-Latino Whites. Hypertension and stroke have significant variability in age patterns among US- and foreign-born Latinos. Conclusions: Recognizing the importance of within-Latino heterogeneity in health is imperative if researchers are to implement social services and health policies aimed at ameliorating the risk of disease. Contribution: Considering intersectional ethnic, nativity, and country-of-origin characteristics among older Latinos is important to better understand the underlying causes of racial/ethnic disparities in morbidity across the life course.

  3. Population of anatomically variable 4D XCAT adult phantoms for imaging research and optimization

    Energy Technology Data Exchange (ETDEWEB)

    Segars, W. P.; Bond, Jason; Frush, Jack; Hon, Sylvia; Eckersley, Chris; Samei, E. [Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Williams, Cameron H.; Frush, D. [Department of Radiology, Duke University Medical Center, Durham, North Carolina 27710 (United States); Feng Jianqiao; Tward, Daniel J.; Ratnanather, J. T.; Miller, M. I. [Center for Imaging Science, Johns Hopkins University, Baltimore, Maryland 21218 (United States)

    2013-04-15

    as a jumping point from which to create an unlimited number of 3D and 4D variations for imaging research. Conclusions: A population of phantoms that includes a range of anatomical variations representative of the public at large is needed to more closely mimic a clinical study or trial. The series of anatomically variable phantoms developed in this work provide a valuable resource for investigating 3D and 4D imaging devices and the effects of anatomy and motion in imaging. Combined with Monte Carlo simulation programs, the phantoms also provide a valuable tool to investigate patient-specific dose and image quality, and optimization for adults undergoing imaging procedures.

  4. Population of anatomically variable 4D XCAT adult phantoms for imaging research and optimization

    International Nuclear Information System (INIS)

    Segars, W. P.; Bond, Jason; Frush, Jack; Hon, Sylvia; Eckersley, Chris; Samei, E.; Williams, Cameron H.; Frush, D.; Feng Jianqiao; Tward, Daniel J.; Ratnanather, J. T.; Miller, M. I.

    2013-01-01

    , serve as a jumping point from which to create an unlimited number of 3D and 4D variations for imaging research. Conclusions: A population of phantoms that includes a range of anatomical variations representative of the public at large is needed to more closely mimic a clinical study or trial. The series of anatomically variable phantoms developed in this work provide a valuable resource for investigating 3D and 4D imaging devices and the effects of anatomy and motion in imaging. Combined with Monte Carlo simulation programs, the phantoms also provide a valuable tool to investigate patient-specific dose and image quality, and optimization for adults undergoing imaging procedures.

  5. Molecular pathways underpinning ethanol-induced neurodegeneration

    Directory of Open Access Journals (Sweden)

    Dan eGoldowitz*

    2014-07-01

    Full Text Available While genetics impacts the type and severity of damage following developmental ethanol exposure, little is currently known about the molecular pathways that mediate these effects. Traditionally, research in this area has used a candidate gene approach and evaluated effects on a gene-by-gene basis. Recent studies, however, have begun to use unbiased approaches and genetic reference populations to evaluate the roles of genotype and epigenetic modifications in phenotypic changes following developmental ethanol exposure, similar to studies that evaluated numerous alcohol-related phenotypes in adults. Here, we present work assessing the role of genetics and chromatin-based alterations in mediating ethanol-induced apoptosis in the developing nervous system. Utilizing the expanded family of BXD recombinant inbred mice, animals were exposed to ethanol at postnatal day 7 via subcutaneous injection (5.0 g/kg in 2 doses. Tissue was collected 7 hours after the initial ethanol treatment and analyzed by activated caspase-3 immunostaining to visualize dying cells in the cerebral cortex and hippocampus. In parallel, the levels of two histone modifications relevant to apoptosis, γH2AX and H3K14 acetylation, were examined in the cerebral cortex using protein blot analysis. Activated caspase-3 staining identified marked differences in cell death across brain regions between different mouse strains. Genetic analysis of ethanol susceptibility in the hippocampus led to the identification of a quantitative trait locus on chromosome 12, which mediates, at least in part, strain-specific differential vulnerability to ethanol-induced apoptosis. Furthermore, analysis of chromatin modifications in the cerebral cortex revealed a global increase in γH2AX levels following ethanol exposure, but did not show any change in H3K14 acetylation levels. Together, these findings provide new insights into the molecular mechanisms and genetic contributions underlying ethanol

  6. Hemodynamic variables predict outcome of emergency thoracotomy in the pediatric trauma population.

    Science.gov (United States)

    Wyrick, Deidre L; Dassinger, Melvin S; Bozeman, Andrew P; Porter, Austin; Maxson, R Todd

    2014-09-01

    Limited data exist regarding indications for resuscitative emergency thoracotomy (ETR) in the pediatric population. We attempt to define the presenting hemodynamic parameters that predict survival for pediatric patients undergoing ETR. We reviewed all pediatric patients (age <18years), entered into the National Trauma Data Bank from 2007 to 2010, who underwent ETR within one hour of ED arrival. Mechanism of injury and hemodynamics were analyzed using Chi squared and Wilcoxon tests. 316 children (70 blunt, 240 penetrating) underwent ETR, 31% (98/316) survived to discharge. Less than 5% of patients survived when presenting SBP was ≤50mmHg or heart rate was ≤70bpm. For blunt injuries there were no survivors with a pulse ≤80bpm or SBP ≤60mmHg. When survivors were compared to nonsurvivors, blood pressure, pulse, and injury type were statistically significant when treated as independent variables and in a logistic regression model. When ETR was performed for SBP ≤50mmHg or for heart rate ≤70bpm less than 5% of patients survived. There were no survivors of blunt trauma when SBP was ≤60mmHg or pulse was ≤80bpm. This review suggests that ETR may have limited benefit in these patients. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. An Integrated Workflow To Assess Technical and Biological Variability of Cell Population Frequencies in Human Peripheral Blood by Flow Cytometry.

    Science.gov (United States)

    Burel, Julie G; Qian, Yu; Lindestam Arlehamn, Cecilia; Weiskopf, Daniela; Zapardiel-Gonzalo, Jose; Taplitz, Randy; Gilman, Robert H; Saito, Mayuko; de Silva, Aruna D; Vijayanand, Pandurangan; Scheuermann, Richard H; Sette, Alessandro; Peters, Bjoern

    2017-02-15

    In the context of large-scale human system immunology studies, controlling for technical and biological variability is crucial to ensure that experimental data support research conclusions. In this study, we report on a universal workflow to evaluate both technical and biological variation in multiparameter flow cytometry, applied to the development of a 10-color panel to identify all major cell populations and T cell subsets in cryopreserved PBMC. Replicate runs from a control donation and comparison of different gating strategies assessed the technical variability associated with each cell population and permitted the calculation of a quality control score. Applying our panel to a large collection of PBMC samples, we found that most cell populations showed low intraindividual variability over time. In contrast, certain subpopulations such as CD56 T cells and Temra CD4 T cells were associated with high interindividual variability. Age but not gender had a significant effect on the frequency of several populations, with a drastic decrease in naive T cells observed in older donors. Ethnicity also influenced a significant proportion of immune cell population frequencies, emphasizing the need to account for these covariates in immune profiling studies. We also exemplify the usefulness of our workflow by identifying a novel cell-subset signature of latent tuberculosis infection. Thus, our study provides a universal workflow to establish and evaluate any flow cytometry panel in systems immunology studies. Copyright © 2017 by The American Association of Immunologists, Inc.

  8. Inter- and intra-population genetic variability of introduced silkworm (Bombyx mori L.) strains raised in Bulgaria

    OpenAIRE

    Teodora Staykova

    2013-01-01

    The genetic variability of four populations belonging to two introduced silkworm strains (Bombyx mori L.) of various origins has been studied using isoenzymic analysis of six enzyme systems. Nonspecific esterases, phosphoglucomutase, malate dehydrogenase, acid phosphatase, alkaline phosphatase and hexokinase from different tissue of larvae 5th instar have been analysed using PAGE. Polymorphism in six from a total of nine loci has been found. Inter- and intra-population differences have been a...

  9. Distribution of microbial populations and their relationship with environmental variables in the North Yellow Sea, China

    Science.gov (United States)

    Bai, Xiaoge; Wang, Min; Liang, Yantao; Zhang, Zhifeng; Wang, Fang; Jiang, Xuejiao

    2012-03-01

    In order to understand the large-scale spatial distribution characteristics of picoplankton, nanophytoplankton and virioplankton and their relationship with environmental variables in coastal and offshore waters, flow cytometry (FCM) was used to analyze microbial abundance of samples collected in summer from four depths at 36 stations in the North Yellow Sea (NYS). The data revealed spatial heterogeneity in microbial populations in the offshore and near-shore waters of the NYS during the summer. For the surface layer, picoeukaryotes were abundant in the near-shore waters, Synechococcus was abundant in the offshore areas, and bacterial and viral abundances were high in the near-shore waters around the Liaodong peninsula. In the near-shore waters, no significant vertical variation of picophytoplankton (0.2-2μm) abundance was found. However, the nanophytoplankton abundance was higher in the upper layers (from the surface to 10 m depth) than in the bottom layer. For the offshore waters, both pico- and nanophytoplankton (2-20μm) abundance decreased sharply with depth in the North Yellow Sea Cold Water Mass (NYSCWM). But, for the vertical distribution of virus and bacteria abundance, no significant variation was observed in both near-shore and offshore waters. Autotrophic microbes were more sensitive to environmental change than heterotrophic microbes and viruses. Viruses showed a positive correlation with bacterial abundance, suggesting that the bacteriophage might be prominent for virioplankton (about 0.45μm) in summer in the NYS and that viral abundance might play an important role in microbial loop functions.

  10. A simple approach to ignoring irrelevant variables by population decoding based on multisensory neurons

    Science.gov (United States)

    Kim, HyungGoo R.; Pitkow, Xaq; Angelaki, Dora E.

    2016-01-01

    Sensory input reflects events that occur in the environment, but multiple events may be confounded in sensory signals. For example, under many natural viewing conditions, retinal image motion reflects some combination of self-motion and movement of objects in the world. To estimate one stimulus event and ignore others, the brain can perform marginalization operations, but the neural bases of these operations are poorly understood. Using computational modeling, we examine how multisensory signals may be processed to estimate the direction of self-motion (i.e., heading) and to marginalize out effects of object motion. Multisensory neurons represent heading based on both visual and vestibular inputs and come in two basic types: “congruent” and “opposite” cells. Congruent cells have matched heading tuning for visual and vestibular cues and have been linked to perceptual benefits of cue integration during heading discrimination. Opposite cells have mismatched visual and vestibular heading preferences and are ill-suited for cue integration. We show that decoding a mixed population of congruent and opposite cells substantially reduces errors in heading estimation caused by object motion. In addition, we present a general formulation of an optimal linear decoding scheme that approximates marginalization and can be implemented biologically by simple reinforcement learning mechanisms. We also show that neural response correlations induced by task-irrelevant variables may greatly exceed intrinsic noise correlations. Overall, our findings suggest a general computational strategy by which neurons with mismatched tuning for two different sensory cues may be decoded to perform marginalization operations that dissociate possible causes of sensory inputs. PMID:27334948

  11. Relative roles of weather variables and change in human population in malaria: comparison over different states of India.

    Directory of Open Access Journals (Sweden)

    Prashant Goswami

    Full Text Available Pro-active and effective control as well as quantitative assessment of impact of climate change on malaria requires identification of the major drivers of the epidemic. Malaria depends on vector abundance which, in turn, depends on a combination of weather variables. However, there remain several gaps in our understanding and assessment of malaria in a changing climate. Most of the studies have considered weekly or even monthly mean values of weather variables, while the malaria vector is sensitive to daily variations. Secondly, rarely all the relevant meteorological variables have been considered together. An important question is the relative roles of weather variables (vector abundance and change in host (human population, in the change in disease load.We consider the 28 states of India, characterized by diverse climatic zones and changing population as well as complex variability in malaria, as a natural test bed. An annual vector load for each of the 28 states is defined based on the number of vector genesis days computed using daily values of temperature, rainfall and humidity from NCEP daily Reanalysis; a prediction of potential malaria load is defined by taking into consideration changes in the human population and compared with the reported number of malaria cases.For most states, the number of malaria cases is very well correlated with the vector load calculated with the combined conditions of daily values of temperature, rainfall and humidity; no single weather variable has any significant association with the observed disease prevalence.The association between vector-load and daily values of weather variables is robust and holds for different climatic regions (states of India. Thus use of all the three weather variables provides a reliable means of pro-active and efficient vector sanitation and control as well as assessment of impact of climate change on malaria.

  12. Century-scale Changes in Environmental Synchrony and Variability and their Effects on Populations of Birds and Reproduction of Trees

    Science.gov (United States)

    Koenig, W.

    2016-12-01

    The ecological impacts of modern global climate change are detectable in a wide variety of phenomena ranging from shifts in species ranges to changes in community composition and human disease dynamics. Thus far, however, little attention has been given to temporal changes in environmental spatial synchrony-the coincident change in abundance or value across the landscape-or environmental variability, despite the importance of these factors as drivers of population rescue and extinction and reproductive dynamics of both animal and plant populations. We quantified spatial synchrony of widespread North American wintering birds species using Audubon Christmas Bird Counts over the past 50 years and seed set variability (mast fruiting) among trees over the past century and found that both spatial synchrony of the birds and seed set variability have significantly increased over these time periods. The first of these results was mirrored by significant increases in spatial synchrony of mean maximum air temperature across North America, primarily during the summer, while the second is consistent with the hypothesis that climate change is resulting in greater seed set variability. These findings suggest the potential for temporal changes in envioronmental synchrony and variability to be affecting a wide range of ecological phenomena by influencing the probability of population rescue and extinction and by affecting ecosystem processes that rely on the resource pulses provided by mast fruiting plants.

  13. Distribution of peak expiratory flow variability by age, gender and smoking habits in a random population sample aged 20-70 yrs

    NARCIS (Netherlands)

    Boezen, H M; Schouten, J. P.; Postma, D S; Rijcken, B

    1994-01-01

    Peak expiratory flow (PEF) variability can be considered as an index of bronchial lability. Population studies on PEF variability are few. The purpose of the current paper is to describe the distribution of PEF variability in a random population sample of adults with a wide age range (20-70 yrs),

  14. Status of vulnerable Cystoseira populations along the Italian infralittoral fringe, and relationships with environmental and anthropogenic variables.

    Science.gov (United States)

    Mancuso, F P; Strain, E M A; Piccioni, E; De Clerck, O; Sarà, G; Airoldi, L

    2017-11-03

    We analyzed the occurrence and status of infralittoral fringe populations of Cystoseira spp. (Fucales) at thirteen rocky sites around the Italian coastline, and explored the relationships with relevant environmental and anthropogenic variables. We found Cystoseira populations at 11 sites: most were scattered and comprised monospecific stands of C. compressa, and only 6 sites also supported sparse specimens of either C. amentacea var. stricta or C. brachycarpa. Coastal human population density, Chlorophyll a seawater concentrations, sea surface temperature, annual range of sea surface temperature and wave fetch explained most of the variation of the status of C. compressa. We hypothesize a generally unhealthy state of the Italian Cystoseira infralittoral fringe populations and identify multiple co-occurring anthropogenic stressors as the likely drivers of these poor conditions. Extensive baseline monitoring is needed to describe how Cystoseira populations are changing, and implement a management framework for the conservation of these valuable but vulnerable habitats. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Effects of subsidized predators, resource variability, and human population density on desert tortoise populations in the Mojave Desert, USA

    Science.gov (United States)

    Esque, Todd C.; Nussear, Kenneth E.; Drake, K. Kristina; Walde, Andrew D.; Berry, Kristin H.; Averill-Murray, Roy C.; Woodman, A. Peter; Boarman, William I.; Medica, Phil A.; Mack, Jeremy S.; Heaton, Jill S.

    2010-01-01

    Understanding predator–prey relationships can be pivotal in the conservation of species. For 2 decades, desert tortoise Gopherus agassizii populations have declined, yet quantitative evidence regarding the causes of declines is scarce. In 2005, Ft. Irwin National Training Center, California, USA, implemented a translocation project including 2 yr of baseline monitoring of desert tortoises. Unusually high predation on tortoises was observed after translocation occurred. We conducted a retrospective analysis of predation and found that translocation did not affect the probability of predation: translocated, resident, and control tortoises all had similar levels of predation. However, predation rates were higher near human population concentrations, at lower elevation sites, and for smaller tortoises and females. Furthermore, high mortality rates were not limited to the National Training Center. In 2008, elevated mortality (as high as 43%) occurred throughout the listed range of the desert tortoise. Although no temporal prey base data are available for analysis from any of the study sites, we hypothesize that low population levels of typical coyote Canis latrans prey (i.e. jackrabbits Lepus californicus and other small animals) due to drought conditions influenced high predation rates in previous years. Predation may have been exacerbated in areas with high levels of subsidized predators. Many historical reports of increased predation, and our observation of a range-wide pattern, may indicate that high predation rates are more common than generally considered and may impact recovery of the desert tortoise throughout its range.

  16. High mutation rates explain low population genetic divergence at copy-number-variable loci in Homo sapiens.

    Science.gov (United States)

    Hu, Xin-Sheng; Yeh, Francis C; Hu, Yang; Deng, Li-Ting; Ennos, Richard A; Chen, Xiaoyang

    2017-02-22

    Copy-number-variable (CNV) loci differ from single nucleotide polymorphic (SNP) sites in size, mutation rate, and mechanisms of maintenance in natural populations. It is therefore hypothesized that population genetic divergence at CNV loci will differ from that found at SNP sites. Here, we test this hypothesis by analysing 856 CNV loci from the genomes of 1184 healthy individuals from 11 HapMap populations with a wide range of ancestry. The results show that population genetic divergence at the CNV loci is generally more than three times lower than at genome-wide SNP sites. Populations generally exhibit very small genetic divergence (G st  = 0.05 ± 0.049). The smallest divergence is among African populations (G st  = 0.0081 ± 0.0025), with increased divergence among non-African populations (G st  = 0.0217 ± 0.0109) and then among African and non-African populations (G st  = 0.0324 ± 0.0064). Genetic diversity is high in African populations (~0.13), low in Asian populations (~0.11), and intermediate in the remaining 11 populations. Few significant linkage disequilibria (LDs) occur between the genome-wide CNV loci. Patterns of gametic and zygotic LDs indicate the absence of epistasis among CNV loci. Mutation rate is about twice as large as the migration rate in the non-African populations, suggesting that the high mutation rates play dominant roles in producing the low population genetic divergence at CNV loci.

  17. Adaptive genetic variability and differentiation of Croatian and Austrian Quercus robur L. populations at a drought prone field trial

    Directory of Open Access Journals (Sweden)

    Saša Bogdan

    2017-07-01

    Full Text Available Provenance trials, where populations of different geographical origin are tested in a common environment (common garden test, are a tool suited to allow the study of intraspecific adaptive genetic variation. Research of pedunculate oak (Quercus robur L. adaptive genetic variability through analyses of populations in common garden tests has a long tradition. However, pedunculated oak populations originating south-eastern from the Alps have been scarcely studied in this way. This study addresses the adaptive genetic variability and differentiation of pedunculate oak populations originating from Austria and Croatia in a provenance/progeny field trial. Studied plants were six years old and were growing at the trial for three years. After two years of unusually low precipitations height and survival were analysed. The total mean height of all plants in the trial was 137.8 cm and ranged from 123.0 cm to 151.8 cm. The overall mean survival rate was rather high (0.85. Mean population survival ranged from 0.64 to 0.94. Individual narrow-sense heritabilities (hi2, family mean heritabilities (hf2, the coefficients of additive genetic variation (CVA and quantitative genetic differentiation coefficients (QST were calculated. A multivariate regression tree (MRT analysis was used to determine the pattern of genetic differentiation of the populations. Individual heritabilities for height ranged between 0.00 and 0.39. Family mean heritabilities for height were rather low in most populations as well (<0.5. Family mean heritabilities for survival were higher than for height (ranging between 0.00 and 0.77. Calculated QST coefficients (0.25 for height and 0.14 for survival indicated between-population genetic differentiation. The populations were separated into two clusters by MRT analysis regarding a climatic variable, namely Hargreaves’ reference evapotranspiration. Populations originating from comparatively more humid habitats were grouped in the first

  18. Escaping the repugnant conclusion: rank-discounted utilitarianism with variable population

    OpenAIRE

    Asheim, Geir Bjarne; Zuber, Stéphane

    2014-01-01

    We contribute to population ethics by proposing and axiomatizing rank-discounted critical-level generalized utilitarianism (RDCLU). Population ethics is needed for evaluation of policies, e.g., concerning climate change, where population size depends on the chosen policy. We show that critical-level generalized utilitarianism and (a version of) critical-level leximin are the limits of RDCLU for extreme values of the rank utility discount factor. Moreover, we establish how RDCLU avoids serious...

  19. Genetic variability of Echinococcus granulosus complex in various geographical populations of Iran inferred by mitochondrial DNA sequences.

    Science.gov (United States)

    Spotin, Adel; Mahami-Oskouei, Mahmoud; Harandi, Majid Fasihi; Baratchian, Mehdi; Bordbar, Ali; Ahmadpour, Ehsan; Ebrahimi, Sahar

    2017-01-01

    To investigate the genetic variability and population structure of Echinococcus granulosus complex, 79 isolates were sequenced from different host species covering human, dog, camel, goat, sheep and cattle as of various geographical sub-populations of Iran (Northwestern, Northern, and Southeastern). In addition, 36 sequences of other geographical populations (Western, Southeastern and Central Iran), were directly retrieved from GenBank database for the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. The confirmed isolates were grouped as G1 genotype (n=92), G6 genotype (n=14), G3 genotype (n=8) and G2 genotype (n=1). 50 unique haplotypes were identified based on the analyzed sequences of cox1. A parsimonious network of the sequence haplotypes displayed star-like features in the overall population containing IR23 (22: 19.1%) as the most common haplotype. According to the analysis of molecular variance (AMOVA) test, the high value of haplotype diversity of E. granulosus complex was shown the total genetic variability within populations while nucleotide diversity was low in all populations. Neutrality indices of the cox1 (Tajima's D and Fu's Fs tests) were shown negative values in Western-Northwestern, Northern and Southeastern populations which indicating significant divergence from neutrality and positive but not significant in Central isolates. A pairwise fixation index (Fst) as a degree of gene flow was generally low value for all populations (0.00647-0.15198). The statistically Fst values indicate that Echinococcus sensu stricto (genotype G1-G3) populations are not genetically well differentiated in various geographical regions of Iran. To appraise the hypothetical evolutionary scenario, further study is needed to analyze concatenated mitogenomes and as well a panel of single locus nuclear markers should be considered in wider areas of Iran and neighboring countries. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Variability of haloxylon ammodendron (C. A. Mey) bunge populations from different habitats

    International Nuclear Information System (INIS)

    Lv, C.

    2015-01-01

    Haloxylon ammodendron (C.A. Mey) Bunge occupies a wide range of different habitats in north-west China. The aim of this study was to quantify variation in population growth characteristics of H. ammodendron from different sites and to relate this variation to different environmental conditions. To this end, 6 populations with visible differences were chosen and a range of morphological as well as seed-related characteristics like density, height, crown, basal diameter, seed mass, 1000 seed weight, seed number, seed diameter and germination rate were measured. The variations in the averages of overall traits were explained. The differences between-populations were 33 percentage, whereas those within population were 67 percentage. The largest variation was detected in morphological-related traits between-populations (38 percentage). In particular, the density, height, 1000 seed weight and germination rate differed strongly between populations. The population growth characteristics were closely related to the soil property at the sites of origin. The soil property can explain most of the variations in the morphological-related traits. They were concluded that the diversity of population growth characteristics in different habitats provides the potential of population reproduction and the protection of original habitats is extremely important. (author)

  1. Uncertain population dynamic and state variables of alfonsino (Beryx splendens Dinámica poblacional incierta y variables de estado en alfonsino (Beryx splendens

    Directory of Open Access Journals (Sweden)

    Rodrigo Wiff

    2012-03-01

    Full Text Available Alfonsino (Beryx splendens is a species associated with seamounts, with an important fishery in Juan Fernandez archipelago, Chile (33°40'S, 79°00'W. Since 2004, this resource has been managed by catch quotas estimated from stock assessment models. The alfonsino model involves high levels of uncertainty for several reasons including a lack of knowledge of aspects of the population dynamics and poorly informative time-series that feed the proposed evaluation models. This work evaluated three hypotheses regarding population dynamics and their influence on the main state variables (biomass, recruitment of the model using age-structured and dynamic biomass models. The hypotheses corresponded to de-recruitment of older individuals, non-linearity between standardized catch per unit effort, and population abundance as well as variations of the relative importance of length structures. According to the results, the depletion of the spawning biomass between 1998 and 2008 varied between 9 and 56%, depending on the combination of hypotheses used in the model. This indicates that state variables in alfonsino are not robust to the available information; rather, they depend strongly on the hypothesis of population dynamics. The discussion is focused on interpreting the causes of the changes in the state variables in light of a conceptual model for population dynamics in alfonsino and which pieces of information would be necessary to reduce the associated uncertainty.El alfonsino (Beryx splendens es una especie asociada a montes submarinos. En Chile sustenta una importante pesquería en el archipiélago de Juan Fernández (33°40'S, 79°00'W. Desde el año 2004, este recurso es administrado a través de cuotas anuales de capturas, las cuales son estimadas desde un modelo de evaluación de stock. La modelación de la población de alfonsino se caracteriza por una alta incertidumbre, debido a diversas fuentes, como son desconocimiento de aspectos de su din

  2. Validation of the Oral Hygiene Habits Scale: Relationships with sociodemographic variables in the general and clinical population of Monterrey, Mexico.

    Directory of Open Access Journals (Sweden)

    Norma Rodríguez

    2016-12-01

    Full Text Available Several socioeconomic factors are associated with poor oral hygiene habits. A version of the Oral Hygiene Habits Scale (OHHS was developed in Mexico to measure these factors; however, its relationship with sociodemographic variables has not been studied. The verification of these relationships could contribute to the validation of the scale. Objective: To evaluate the relationship between oral hygiene habits and sociodemographic variables of sex, age, schooling, self-defined socioeconomic stratum, occupation and marital status in the general and clinical population of Monterrey, Mexico. Materials and Methods: A general population sample (GPS of 256 participants and a clinical sample (CPS of 240 participants were studied. The OHHS consisted of an eight-item Likert scale of 4 points ranging from 0 to 4. A descriptive correlational study was performed with a cross-sectional design. Data were analyzed using the Mann-Whitney U test, Kruskal-Wallis test, Spearman correlation coefficient, Cramer's V coefficient, and multivariate aligned rank test. Results: In GPS and CPS groups, OHHS was related to sex, schooling, socioeconomic stratum, occupation and marital status, but not to age. There were no significant interactions between the samples (GPS and CPS and sociodemographic variables. Conclusion: There is a statistically significant relationship between oral hygiene habits and some sociodemographic variables in the general and clinical population. This relationship supports the validity of the OHHS.

  3. Seasonal temperature variability and emergency hospital admissions for respiratory diseases: a population-based cohort study.

    Science.gov (United States)

    Sun, Shengzhi; Laden, Francine; Hart, Jaime E; Qiu, Hong; Wang, Yan; Wong, Chit Ming; Lee, Ruby Siu-Yin; Tian, Linwei

    2018-04-05

    Climate change increases global mean temperature and changes short-term (eg, diurnal) and long-term (eg, intraseasonal) temperature variability. Numerous studies have shown that mean temperature and short-term temperature variability are both associated with increased respiratory morbidity or mortality. However, data on the impact of long-term temperature variability are sparse. We aimed to assess the association of intraseasonal temperature variability with respiratory disease hospitalisations among elders. We ascertained the first occurrence of emergency hospital admissions for respiratory diseases in a prospective Chinese elderly cohort of 66 820 older people (≥65 years) with 10-13 years of follow-up. We used an ordinary kriging method based on 22 weather monitoring stations in Hong Kong to spatially interpolate daily ambient temperature for each participant's residential address. Seasonal temperature variability was defined as the SD of daily mean summer (June-August) or winter (December-February) temperatures. We applied Cox proportional hazards regression with time-varying exposure of seasonal temperature variability to respiratory admissions. During the follow-up time, we ascertained 12 689 cases of incident respiratory diseases, of which 6672 were pneumonia and 3075 were COPD. The HRs per 1°C increase in wintertime temperature variability were 1.20 (95% CI 1.08 to 1.32), 1.15 (1.01 to 1.31) and 1.41 (1.15 to 1.71) for total respiratory diseases, pneumonia and COPD, respectively. The associations were not statistically significant for summertime temperature variability. Wintertime temperature variability was associated with higher risk of incident respiratory diseases. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  4. Variability of morphological needle traits of Scots pine (Pinus sylvestris L. among populations from mountain and lowland regions of Poland

    Directory of Open Access Journals (Sweden)

    Łabiszak Bartosz

    2017-06-01

    Full Text Available The main goal of this work was to examine interpopulational needle traits variability of Scots pine (Pinus sylvestris L. from four mountain, one foothill and three lowland, natural populations located in Poland. This choice of locations was motivated by the presumed different origins of mountainous populations and the necessity to demonstrate how closely they are related to lowland populations. Variation in the studied populations was determined using seven morphological traits of needles: 1 - needle length, 2 - number of stomatal rows on the flat side of a needle, 3 - number of stomata per 2 mm of needle length on the flat side, 4 - number of stomatal rows on the convex side of a needle, 5 - number of stomata per 2 mm of needle length on the convex side, 6 - number of serrations per 2 mm of the needle length on the left side and 7 - number of serrations per 2 mm of the needle length on the right side. Biometric data were analysed statistically, and it was found that (i needle traits differentiate studied populations; (ii the postulated division of the population into two groups is reflected in the obtained results; and (iii a particularly strong relationship was found between two relict pine populations from the Pieniny (Sokolica, Kazalnica, Czertezik and Tatra Mts. (Wielke Koryciska, which may be the result of the common origins and history of these two populations

  5. Effects of population variability on the accuracy of detection probability estimates

    DEFF Research Database (Denmark)

    Ordonez Gloria, Alejandro

    2011-01-01

    Observing a constant fraction of the population over time, locations, or species is virtually impossible. Hence, quantifying this proportion (i.e. detection probability) is an important task in quantitative population ecology. In this study we determined, via computer simulations, the ef- fect of...

  6. Climate variability, human wildlife conflict and population dynamics of lions Panthera leo

    Science.gov (United States)

    Trinkel, Martina

    2013-04-01

    Large carnivores are threatened by habitat loss, declining prey populations and direct persecution. Pride dynamics of eight lion prides in the centre of the Etosha National Park, Namibia are described during a 16-year study. Since the beginning of the 1980s, the number of adult and subadult lions declined continuously to two third of its initial population size, and reached a new equilibrium in the 1990s. Pride sizes decreased from 6.3 adult females in 1989 to 2.8 lionesses in 1997. While the number of adult females declined continuously, the number of adult males, subadult females and subadult males remained constant over the years. A severe drought period, lasting for more than 20 years, led to declining prey populations inside the lions' territory. Besides declining prey populations, conflict with humans at the border of Etosha puts substantial pressure onto the lion population: 82 % of all known lion mortalities were caused by humans, and most of these consisted of adult females (28 %) and subadult males (29 %). I postulate that the considerable decline in the lion population is a response to declining prey populations, and although the human predator conflict is severe, it does not seem to limit the size of Etosha's lion population.

  7. Fish population studies using parasites from the Southeastern Pacific Ocean: considering host population changes and species body size as sources of variability of parasite communities.

    Science.gov (United States)

    George-Nascimento, Mario; Oliva, Marcelo

    2015-01-01

    Research using parasites in fish population studies in the South Eastern Pacific (SEP) is summarized. There are 27 such studies (snapshots mainly) in single host species sampled at different geographic localities and at somewhat similar times. They have been devoted mainly to economically important species, though others on coastal and intertidal fish or on less- or non-commercial species provide insights on scales of temporal and spatial variation of parasite infracommunities. Later, we assess whether the probability of harbouring parasites depends on the host species body size. Our results indicate that a stronger tool for fish population studies may be developed under regular (long term) scrutiny of parasite communities, especially of small fish host species, due to their larger variability in richness, abundance and total biomass, than in large fish species. Finally, it might also be necessary to consider the effects of fishing on parasite communities as well as the natural oscillations (coupled or not) of host and parasite populations.

  8. GENETIC VARIABILITY OF POLYMESODA EROSA POPULATION IN THE SEGARA ANAKAN CILACAP

    Directory of Open Access Journals (Sweden)

    AGUS NURYANTO

    2010-01-01

    Full Text Available Mud clams, Polymesoda erosa, in the Segara Anakan Cilacap are highly exploited by the local communities for daily consumption. This is presumed causing population decline and potentially causing loss of genetic diversity. Genetic diversity level within population can be obtained by population genetic study using molecular marker such as randomly amplified polymorphic DNA (RAPD. Here we amplified RAPD marker using ten arbitrary primers to assess genetic diversity of P. erosa population in the Segara Anakan Cilacap to provide genetic data for its sustainable use. The results proved that the use of RAPD marker has high polymorphisms. The mud clam population also showed a high level of heterozygosity and genetic diversity. This has important implication for the management plan towards sustainable use of P. erosa in the Segara Anakan Cilacap.

  9. Genetic variability of populations of Nyssomyia neivai in the Northern State of Paraná, Brazil

    Science.gov (United States)

    Gasparotto, Jaqueline de Carvalho; da Costa-Ribeiro, Magda Clara Vieira; Thomaz-Soccol, Vanete; Liebel, Sandra Mara Rodrigues da Silva; Neitzke-Abreu, Herintha Coeto; Reinhold-Castro, Kárin Rosi; Cristovão, Edilson Colhera; Teodoro, Ueslei

    2017-01-01

    ABSTRACT The genetic study of sandfly populations needs to be further explored given the importance of these insects for public health. Were sequenced the NDH4 mitochondrial gene from populations of Nyssomyia neivai from Doutor Camargo, Lobato, Japira, and Porto Rico, municipalities in the State of Paraná, Brazil, to understand the genetic structure and gene flow. Eighty specimens of Ny. Neivai were sequenced, 20 from each municipality, and 269 base pairs were obtained. A total of 27 haplotypes and 28 polymorphic sites were found, along with a haplotypic diversity of 0.80696 and a nucleotide diversity of 0.00567. Haplotype H5, with 33 specimens, was the most common among the four populations. Only haplotypes H5 and H7 were present in all four populations. The population from Doutor Camargo showed the highest genetic diversity, and only this population shared haplotypes with those from the other municipalities. The highest number of haplotypes was sheared with Lobato which also had the highest number of unique haplotypes. This probably occurred because of constant anthropic changes that happened in the environment during the first half of the twentieth century, mainly after 1998. There was no significant correlation between genetic and geographical distances regarding these populations. However, the highest genetic and geographical distances, and the lowest gene flow were observed between Japira and Porto Rico. Geographical distance is a possible barrier between these municipalities through the blocking of haplotype sharing. PMID:28380111

  10. Genetic variability of populations of Nyssomyia neivai in the Northern State of Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Jaqueline de Carvalho Gasparotto

    Full Text Available ABSTRACT The genetic study of sandfly populations needs to be further explored given the importance of these insects for public health. Were sequenced the NDH4 mitochondrial gene from populations of Nyssomyia neivai from Doutor Camargo, Lobato, Japira, and Porto Rico, municipalities in the State of Paraná, Brazil, to understand the genetic structure and gene flow. Eighty specimens of Ny. Neivai were sequenced, 20 from each municipality, and 269 base pairs were obtained. A total of 27 haplotypes and 28 polymorphic sites were found, along with a haplotypic diversity of 0.80696 and a nucleotide diversity of 0.00567. Haplotype H5, with 33 specimens, was the most common among the four populations. Only haplotypes H5 and H7 were present in all four populations. The population from Doutor Camargo showed the highest genetic diversity, and only this population shared haplotypes with those from the other municipalities. The highest number of haplotypes was sheared with Lobato which also had the highest number of unique haplotypes. This probably occurred because of constant anthropic changes that happened in the environment during the first half of the twentieth century, mainly after 1998. There was no significant correlation between genetic and geographical distances regarding these populations. However, the highest genetic and geographical distances, and the lowest gene flow were observed between Japira and Porto Rico. Geographical distance is a possible barrier between these municipalities through the blocking of haplotype sharing.

  11. [Genetic variability and differentiation of three Russian populations of yellow potato cyst nematode Globodera rostochiensis as revealed by nuclear markers].

    Science.gov (United States)

    Khrisanfova, G G; Kharchevnikov, D A; Popov, I O; Zinov'eva, S V; Semenova, S K

    2008-05-01

    Genetic variability of yellow potato cyst nematode G. rostochiensis from three Russian populations (Karelia, Vladimir oblast, and Moscow oblast) was investigated using two types of nuclear markers. Using RAPD markers identified with the help of six random primers (P-29, OPA-10, OPT-14, OPA-11, OPB-11, and OPH-20), it was possible to distinguish Karelian population from the group consisting of the populations from two adjacent regions (Moscow oblast and Vladimir oblast). Based on the combined matrix, containing 294 RAPD fragments, dendrogram of genetic differences was constructed, and the indices of genetic divergence and partition (P, H, and G(st)), as well as the gene flow indices N(m) between the nematode samples examined, were calculated. The dendrogram structure, genetic diversity indices, and variations of genetic distances between single individuals in each population from Karelia and Central Russia pointed to genetic isolation and higher genetic diversity of the nematodes from Karelia. Based on polymorphism of rDNA first intergenic spacer ITS1, attribution of all populations examined to the species G. rostochiensis was proved. Small variations of the ITS1 sequence in different geographic populations of nematodes from different regions of the species world range did not allow isolation of separate groups within the species. Possible factors (including interregional transportations of seed potato) affecting nematode population structure in Russia are discussed.

  12. Sensitivity of Anopheles gambiae population dynamics to meteo-hydrological variability: a mechanistic approach

    Directory of Open Access Journals (Sweden)

    Gilioli Gianni

    2011-10-01

    Full Text Available Abstract Background Mechanistic models play an important role in many biological disciplines, and they can effectively contribute to evaluate the spatial-temporal evolution of mosquito populations, in the light of the increasing knowledge of the crucial driving role on vector dynamics played by meteo-climatic features as well as other physical-biological characteristics of the landscape. Methods In malaria eco-epidemiology landscape components (atmosphere, water bodies, land use interact with the epidemiological system (interacting populations of vector, human, and parasite. In the background of the eco-epidemiological approach, a mosquito population model is here proposed to evaluate the sensitivity of An. gambiae s.s. population to some peculiar thermal-pluviometric scenarios. The scenarios are obtained perturbing meteorological time series data referred to four Kenyan sites (Nairobi, Nyabondo, Kibwesi, and Malindi representing four different eco-epidemiological settings. Results Simulations highlight a strong dependence of mosquito population abundance on temperature variation with well-defined site-specific patterns. The upper extreme of thermal perturbation interval (+ 3°C gives rise to an increase in adult population abundance at Nairobi (+111% and Nyabondo (+61%, and a decrease at Kibwezi (-2% and Malindi (-36%. At the lower extreme perturbation (-3°C is observed a reduction in both immature and adult mosquito population in three sites (Nairobi -74%, Nyabondo -66%, Kibwezi -39%, and an increase in Malindi (+11%. A coherent non-linear pattern of population variation emerges. The maximum rate of variation is +30% population abundance for +1°C of temperature change, but also almost null and negative values are obtained. Mosquitoes are less sensitive to rainfall and both adults and immature populations display a positive quasi-linear response pattern to rainfall variation. Conclusions The non-linear temperature-dependent response is in

  13. Genotypic and allelic variability in CYP19A1 among populations of African and European ancestry.

    Directory of Open Access Journals (Sweden)

    Athena Starlard-Davenport

    Full Text Available CYP19A1 facilitates the bioconversion of estrogens from androgens. CYP19A1 intron single nucleotide polymorphisms (SNPs may alter mRNA splicing, resulting in altered CYP19A1 activity, and potentially influencing disease susceptibility. Genetic studies of CYP19A1 SNPs have been well documented in populations of European ancestry; however, studies in populations of African ancestry are limited. In the present study, ten 'candidate' intronic SNPs in CYP19A1 from 125 African Americans (AA and 277 European Americans (EA were genotyped and their frequencies compared. Allele frequencies were also compared with HapMap and ASW 1000 Genomes populations. We observed significant differences in the minor allele frequencies between AA and EA in six of the ten SNPs including rs10459592 (p<0.0001, rs12908960 (p<0.0001, rs1902584 (p = 0.016, rs2470144 (p<0.0001, rs1961177 (p<0.0001, and rs6493497 (p = 0.003. While there were no significant differences in allele frequencies between EA and CEU in the HapMap population, a 1.2- to 19-fold difference in allele frequency for rs10459592 (p = 0.004, rs12908960 (p = 0.0006, rs1902584 (p<0.0001, rs2470144 (p = 0.0006, rs1961177 (p<0.0001, and rs6493497 (p = 0.0092 was observed between AA and the Yoruba (YRI population. Linkage disequilibrium (LD blocks and haplotype clusters that is unique to the EA population but not AA was also observed. In summary, we demonstrate that differences in the allele frequencies of CYP19A1 intron SNPs are not consistent between populations of African and European ancestry. Thus, investigations into whether CYP19A1 intron SNPs contribute to variations in cancer incidence, outcomes and pharmacological response seen in populations of different ancestry may prove beneficial.

  14. Population of computational rabbit-specific ventricular action potential models for investigating sources of variability in cellular repolarisation.

    Directory of Open Access Journals (Sweden)

    Philip Gemmell

    Full Text Available Variability is observed at all levels of cardiac electrophysiology. Yet, the underlying causes and importance of this variability are generally unknown, and difficult to investigate with current experimental techniques. The aim of the present study was to generate populations of computational ventricular action potential models that reproduce experimentally observed intercellular variability of repolarisation (represented by action potential duration and to identify its potential causes. A systematic exploration of the effects of simultaneously varying the magnitude of six transmembrane current conductances (transient outward, rapid and slow delayed rectifier K(+, inward rectifying K(+, L-type Ca(2+, and Na(+/K(+ pump currents in two rabbit-specific ventricular action potential models (Shannon et al. and Mahajan et al. at multiple cycle lengths (400, 600, 1,000 ms was performed. This was accomplished with distributed computing software specialised for multi-dimensional parameter sweeps and grid execution. An initial population of 15,625 parameter sets was generated for both models at each cycle length. Action potential durations of these populations were compared to experimentally derived ranges for rabbit ventricular myocytes. 1,352 parameter sets for the Shannon model and 779 parameter sets for the Mahajan model yielded action potential duration within the experimental range, demonstrating that a wide array of ionic conductance values can be used to simulate a physiological rabbit ventricular action potential. Furthermore, by using clutter-based dimension reordering, a technique that allows visualisation of multi-dimensional spaces in two dimensions, the interaction of current conductances and their relative importance to the ventricular action potential at different cycle lengths were revealed. Overall, this work represents an important step towards a better understanding of the role that variability in current conductances may play in

  15. Population of computational rabbit-specific ventricular action potential models for investigating sources of variability in cellular repolarisation.

    Science.gov (United States)

    Gemmell, Philip; Burrage, Kevin; Rodriguez, Blanca; Quinn, T Alexander

    2014-01-01

    Variability is observed at all levels of cardiac electrophysiology. Yet, the underlying causes and importance of this variability are generally unknown, and difficult to investigate with current experimental techniques. The aim of the present study was to generate populations of computational ventricular action potential models that reproduce experimentally observed intercellular variability of repolarisation (represented by action potential duration) and to identify its potential causes. A systematic exploration of the effects of simultaneously varying the magnitude of six transmembrane current conductances (transient outward, rapid and slow delayed rectifier K(+), inward rectifying K(+), L-type Ca(2+), and Na(+)/K(+) pump currents) in two rabbit-specific ventricular action potential models (Shannon et al. and Mahajan et al.) at multiple cycle lengths (400, 600, 1,000 ms) was performed. This was accomplished with distributed computing software specialised for multi-dimensional parameter sweeps and grid execution. An initial population of 15,625 parameter sets was generated for both models at each cycle length. Action potential durations of these populations were compared to experimentally derived ranges for rabbit ventricular myocytes. 1,352 parameter sets for the Shannon model and 779 parameter sets for the Mahajan model yielded action potential duration within the experimental range, demonstrating that a wide array of ionic conductance values can be used to simulate a physiological rabbit ventricular action potential. Furthermore, by using clutter-based dimension reordering, a technique that allows visualisation of multi-dimensional spaces in two dimensions, the interaction of current conductances and their relative importance to the ventricular action potential at different cycle lengths were revealed. Overall, this work represents an important step towards a better understanding of the role that variability in current conductances may play in experimentally

  16. Examining the infrared variable star population discovered in the Small Magellanic Cloud using the SAGE-SMC survey

    Energy Technology Data Exchange (ETDEWEB)

    Polsdofer, Elizabeth; Marengo, M. [Iowa State University, Department of Physics and Astronomy, 12 Physics Hall, Ames, Iowa 50011 (United States); Seale, J.; Sewiło, M. [The Johns Hopkins University, Department of Physics and Astronomy, 366 Bloomberg Center, 3400 N. Charles Street, Baltimore, MD 21218 (United States); Vijh, U. P.; Terrazas, M. [Ritter Astrophysical Research Center, University of Toledo, Toledo, OH 43606 (United States); Meixner, M., E-mail: empolsdofer@gmail.com [Space Telescope Science Institute, 3700 San Martin Dr., Baltimore, MD 21218 (United States)

    2015-02-01

    We present our study on the infrared variability of point sources in the Small Magellanic Cloud (SMC). We use the data from the Spitzer Space Telescope Legacy Program “Surveying the Agents of Galaxy Evolution in the Tidally Stripped, Low Metallicity Small Magellanic Cloud” (SAGE-SMC) and the “Spitzer Survey of the Small Magellanic Cloud” (S{sup 3}MC) survey, over three different epochs, separated by several months to 3 years. Variability in the thermal infrared is identified using a combination of Spitzer’s InfraRed Array Camera 3.6, 4.5, 5.8, and 8.0 μm bands, and the Multiband Imaging Photometer for Spitzer 24 μm band. An error-weighted flux difference between each pair of three epochs (“variability index”) is used to assess the variability of each source. A visual source inspection is used to validate the photometry and image quality. Out of ∼2 million sources in the SAGE-SMC catalog, 814 meet our variability criteria. We matched the list of variable star candidates to the catalogs of SMC sources classified with other methods, available in the literature. Carbon-rich Asymptotic Giant Branch (AGB) stars make up the majority (61%) of our variable sources, with about a third of all of our sources being classified as extreme AGB stars. We find a small, but significant population of oxygen-rich (O-rich) AGB (8.6%), Red Supergiant (2.8%), and Red Giant Branch (<1%) stars. Other matches to the literature include Cepheid variable stars (8.6%), early type stars (2.8%), Young-stellar objects (5.8%), and background galaxies (1.2%). We found a candidate OH maser star, SSTISAGE1C J005212.88-730852.8, which is a variable O-rich AGB star, and would be the first OH/IR star in the SMC, if confirmed. We measured the infrared variability of a rare RV Tau variable (a post-AGB star) that has recently left the AGB phase. 59 variable stars from our list remain unclassified.

  17. Examining the infrared variable star population discovered in the Small Magellanic Cloud using the SAGE-SMC survey

    International Nuclear Information System (INIS)

    Polsdofer, Elizabeth; Marengo, M.; Seale, J.; Sewiło, M.; Vijh, U. P.; Terrazas, M.; Meixner, M.

    2015-01-01

    We present our study on the infrared variability of point sources in the Small Magellanic Cloud (SMC). We use the data from the Spitzer Space Telescope Legacy Program “Surveying the Agents of Galaxy Evolution in the Tidally Stripped, Low Metallicity Small Magellanic Cloud” (SAGE-SMC) and the “Spitzer Survey of the Small Magellanic Cloud” (S 3 MC) survey, over three different epochs, separated by several months to 3 years. Variability in the thermal infrared is identified using a combination of Spitzer’s InfraRed Array Camera 3.6, 4.5, 5.8, and 8.0 μm bands, and the Multiband Imaging Photometer for Spitzer 24 μm band. An error-weighted flux difference between each pair of three epochs (“variability index”) is used to assess the variability of each source. A visual source inspection is used to validate the photometry and image quality. Out of ∼2 million sources in the SAGE-SMC catalog, 814 meet our variability criteria. We matched the list of variable star candidates to the catalogs of SMC sources classified with other methods, available in the literature. Carbon-rich Asymptotic Giant Branch (AGB) stars make up the majority (61%) of our variable sources, with about a third of all of our sources being classified as extreme AGB stars. We find a small, but significant population of oxygen-rich (O-rich) AGB (8.6%), Red Supergiant (2.8%), and Red Giant Branch (<1%) stars. Other matches to the literature include Cepheid variable stars (8.6%), early type stars (2.8%), Young-stellar objects (5.8%), and background galaxies (1.2%). We found a candidate OH maser star, SSTISAGE1C J005212.88-730852.8, which is a variable O-rich AGB star, and would be the first OH/IR star in the SMC, if confirmed. We measured the infrared variability of a rare RV Tau variable (a post-AGB star) that has recently left the AGB phase. 59 variable stars from our list remain unclassified.

  18. Duty of care is underpinned by a range of obligations.

    Science.gov (United States)

    Griffith, Richard

    The courts have long established that nurses are in a duty situation and owe a duty of care to their patients (Kent v Griffiths [2001]). Traditionally, the profession set the standard of care and nurses were required to act in accordance with a practice accepted by a responsible body of their peers (Bolam v Friern HMC [1957]).The introduction of the Human Rights Act 1998 gave rise to a positive obligation on government to ensure that laws, policies and procedures are in place to protect violations of human rights. Nurses must now inform their practice with relevant statute law, common law and professional standards in order to properly discharge their duty of care. Richard Griffith considers the law that now underpins a nurse's duty of care and uses a recent report from the Health Service Ombudsman for England to illustrate the obligations that underpin the nurse-patient relationship.

  19. Multi-objective optimization in systematic conservation planning and the representation of genetic variability among populations.

    Science.gov (United States)

    Schlottfeldt, S; Walter, M E M T; Carvalho, A C P L F; Soares, T N; Telles, M P C; Loyola, R D; Diniz-Filho, J A F

    2015-06-18

    Biodiversity crises have led scientists to develop strategies for achieving conservation goals. The underlying principle of these strategies lies in systematic conservation planning (SCP), in which there are at least 2 conflicting objectives, making it a good candidate for multi-objective optimization. Although SCP is typically applied at the species level (or hierarchically higher), it can be used at lower hierarchical levels, such as using alleles as basic units for analysis, for conservation genetics. Here, we propose a method of SCP using a multi-objective approach. We used non-dominated sorting genetic algorithm II in order to identify the smallest set of local populations of Dipteryx alata (baru) (a Brazilian Cerrado species) for conservation, representing the known genetic diversity and using allele frequency information associated with heterozygosity and Hardy-Weinberg equilibrium. We worked in 3 variations for the problem. First, we reproduced a previous experiment, but using a multi-objective approach. We found that the smallest set of populations needed to represent all alleles under study was 7, corroborating the results of the previous study, but with more distinct solutions. In the 2nd and 3rd variations, we performed simultaneous optimization of 4 and 5 objectives, respectively. We found similar but refined results for 7 populations, and a larger portfolio considering intra-specific diversity and persistence with populations ranging from 8-22. This is the first study to apply multi-objective algorithms to an SCP problem using alleles at the population level as basic units for analysis.

  20. Genomic patterns in Acropora cervicornis show extensive population structure and variable genetic diversity.

    Science.gov (United States)

    Drury, Crawford; Schopmeyer, Stephanie; Goergen, Elizabeth; Bartels, Erich; Nedimyer, Ken; Johnson, Meaghan; Maxwell, Kerry; Galvan, Victor; Manfrino, Carrie; Lirman, Diego

    2017-08-01

    Threatened Caribbean coral communities can benefit from high-resolution genetic data used to inform management and conservation action. We use Genotyping by Sequencing (GBS) to investigate genetic patterns in the threatened coral, Acropora cervicornis , across the Florida Reef Tract (FRT) and the western Caribbean. Results show extensive population structure at regional scales and resolve previously unknown structure within the FRT. Different regions also exhibit up to threefold differences in genetic diversity (He), suggesting targeted management based on the goals and resources of each population is needed. Patterns of genetic diversity have a strong spatial component, and our results show Broward and the Lower Keys are among the most diverse populations in Florida. The genetic diversity of Caribbean staghorn coral is concentrated within populations and within individual reefs (AMOVA), highlighting the complex mosaic of population structure. This variance structure is similar over regional and local scales, which suggests that in situ nurseries are adequately capturing natural patterns of diversity, representing a resource that can replicate the average diversity of wild assemblages, serving to increase intraspecific diversity and potentially leading to improved biodiversity and ecosystem function. Results presented here can be translated into specific goals for the recovery of A. cervicornis , including active focus on low diversity areas, protection of high diversity and connectivity, and practical thresholds for responsible restoration.

  1. Spatio-temporal environmental correlation and population variability in simple metacommunities.

    Directory of Open Access Journals (Sweden)

    Lasse Ruokolainen

    Full Text Available Natural populations experience environmental conditions that vary across space and over time. This variation is often correlated between localities depending on the geographical separation between them, and different species can respond to local environmental fluctuations similarly or differently, depending on their adaptation. How this emerging structure in environmental correlation (between-patches and between-species affects spatial community dynamics is an open question. This paper aims at a general understanding of the interactions between the environmental correlation structure and population dynamics in spatial networks of local communities (metacommunities, by studying simple two-patch, two-species systems. Three different pairs of interspecific interactions are considered: competition, consumer-resource interaction, and host-parasitoid interaction. While the results paint a relatively complex picture of the effect of environmental correlation, the interaction between environmental forcing, dispersal, and local interactions can be understood via two mechanisms. While increasing between-patch environmental correlation couples immigration and local densities (destabilising effect, the coupling between local populations under increased between-species environmental correlation can either amplify or dampen population fluctuations, depending on the patterns in density dependence. This work provides a unifying framework for modelling stochastic metacommunities, and forms a foundation for a better understanding of population responses to environmental fluctuations in natural systems.

  2. Analysis of genetic variability in the Czech Dachshund population using microsatellite markers

    Czech Academy of Sciences Publication Activity Database

    Přibáňová, M.; Horák, Pavel; Schröffelová, D.; Urban, T.; Bechyňová, Renata; Musilová, L.

    2009-01-01

    Roč. 126, - (2009), s. 311-318 ISSN 0931-2668 R&D Projects: GA AV ČR 1QS500450578; GA ČR GD523/03/H076 Institutional research plan: CEZ:AV0Z50450515 Keywords : dachshund * dog * genetic variability * microsatellite Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.706, year: 2009

  3. An Examination of Prescription Stimulant Misuse and Psychological Variables among Sorority and Fraternity College Populations

    Science.gov (United States)

    Dussault, Crystal L.; Weyandt, Lisa L.

    2013-01-01

    Objective: The objective of this study was to examine nonmedical stimulant use among fraternity/sorority members and nonmembers and whether psychological variables (e.g., internal restlessness, depression, anxiety, and stress) were related to nonmedical stimulant use. Method: The sample consisted of 1,033 undergraduate students from five…

  4. Can Neoclassical Economics Underpin the Reform of Centrally Planned Economies?

    OpenAIRE

    Peter Murrell

    1991-01-01

    This paper addresses whether neoclassical economics can provide the intellectual underpinning for a theory of reform. I examine whether the neoclassical model satisfies an essential condition to qualify for this role: does it give us a satisfactory explanation for the vast differences in performance between capitalist and socialist economic systems? First, I focus on the theoretical arguments that have traditionally been used to examine the comparative properties of central planning and marke...

  5. Neural and psychological underpinnings of gambling disorder: A review

    OpenAIRE

    Grant, Jon E; Odlaug, Brian L; Chamberlain, Sam

    2015-01-01

    Gambling disorder affects 0.4 to 1.6% of adults worldwide, and is highly comorbid with other mental health disorders. This article provides a concise primer on the neural and psychological underpinnings of gambling disorder based on a selective review of the literature. Gambling disorder is associated with dysfunction across multiple cognitive domains which can be considered in terms of impulsivity and compulsivity. Neuroimaging data suggest structural and functional abnormalities of networks...

  6. Genetic variability of a population of Aedes aegypti from Paraná, Brazil, using the mitochondrial ND4 gene

    Directory of Open Access Journals (Sweden)

    Adriana L. Twerdochlib

    2012-06-01

    Full Text Available Genetic variability of a population of Aedes aegypti from Paraná, Brazil, using the mitochondrial ND4 gene. To analyze the genetic variability of populations of Aedes aegypti, 156 samples were collected from 10 municipalities in the state of Paraná, Brazil. A 311 base pairs (bp region of the NADH dehydrogenase subunit 4 (ND4 mitochondrial gene was examined. An analysis of this fragment identified eight distinct haplotypes. The mean genetic diversity was high (h = 0.702; p = 0.01556. AMOVA analysis indicated that most of the variation (67% occurred within populations and the F ST value (0.32996 was highly significant. F ST values were significant in most comparisons among cities. The isolation by distance was not significant (r = -0.1216 and p = 0, 7550, indicating that genetic distance is not related to geographic distance. Neighbor-joining analysis showed two genetically distinct groups within Paraná. The DNA polymorphism and AMOVA data indicate a decreased gene flow in populations from Paraná, which can result in increased vectorial competence.

  7. The mechanisms underpinning peer support: a literature review.

    Science.gov (United States)

    Watson, Emma

    2017-12-20

    The employment of Peer Support Workers, who themselves have experience of significant emotional distress, can promote recovery at an individual and organisational level. While research examining the benefits of peer support within mental health services continues to grow, an understanding of how, and through what processes, these benefits are reached remains under-developed. To review the published research literature relating to the process of peer support and its underpinning mechanisms to better understand how and why it works. A scoping review of published literature identified studies relating to peer support mechanisms, processes and relationships. Studies were summarised and findings analysed. Five mechanisms were found to underpin peer support relationships (lived experience, love labour, the liminal position of the peer worker, strengths-focussed social and practical support, and the helper role). The identified mechanisms can underpin both the success and difficulties associated with peer support relationships. Further research should review a broader range of literature and clarify how these mechanisms contribute to peer support in different contexts.

  8. Within-population isotopic niche variability in savanna mammals: disparity between carnivores and herbivores

    Directory of Open Access Journals (Sweden)

    Daryl eCodron

    2016-02-01

    Full Text Available Large mammal ecosystems have relatively simple food webs, usually comprising three – and sometimes only two – trophic links. Since many syntopic species from the same trophic level therefore share resources, dietary niche partitioning features prominently within these systems. In African and other subtropical savannas, stable carbon isotopes readily distinguish between herbivore species for which foliage and other parts of dicot plants (13C-depleted C3 vegetation are the primary resource (browsers and those for which grasses (13C-enriched C4 vegetation are staples (grazers. Similarly, carbon isotopes distinguish between carnivore diets that may be richer in either browser, grazer, or intermediate-feeding prey. Here, we investigate levels of carbon and nitrogen isotopic niche variation and niche partitioning within populations (or species of carnivores and herbivores from South African savannas. We emphasize predictable differences in within-population trends across trophic levels: we expect that herbivore populations, which require more foraging effort due to higher intake requirements, are far less likely to display within-population resource partitioning than carnivore populations. Our results reveal generally narrower isotopic niche breadths in herbivore than carnivore populations, but more importantly we find lower levels of isotopic differentiation across individuals within herbivore species. While these results offer some support for our general hypothesis, the current paucity of isotopic data for African carnivores limits our ability to test the complete set of predictions arising from our hypothesis. Nevertheless, given the different ecological and ecophysiological constraints to foraging behaviour within each trophic level, comparisons across carnivores and herbivores, which are possible within such simplified foodwebs, make these systems ideal for developing a process-based understanding of conditions underlying the evolution of

  9. Comorbid Disorders and Sociodemographic Variables in Temporomandibular Pain in the General Dutch Population

    NARCIS (Netherlands)

    Visscher, Corine M.; Ligthart, Lannie; Schuller, Annemarie A.; Lobbezoo, Frank; de Jongh, Ad; van Houtem, Caroline M. H. H.; Boomsma, Dorret I.

    2015-01-01

    Aims: (1) To determine the prevalence of temporomandibular disorder (TMD) pain complaints in the general Dutch population; (2) to investigate its relationship with age, sex, educational attainment, and country of birth; (3) to determine its association with other pain complaints; and (4) to

  10. Comorbid disorders and sociodemographic variables in temporomandibular pain in the general Dutch population

    NARCIS (Netherlands)

    Visscher, C.M.; Ligthart, L.; Schuller, A.A.; Lobbezoo, F.; de Jongh, A.; van Houtem, C.M.H.H.; Boomsma, D.I.

    2015-01-01

    Aims: (1) To determine the prevalence of temporomandibular disorder (TMD)-pain complaints in the general Dutch population; (2) to investigate its relationship with age, sex, educational attainment, and country of birth; (3) to determine its association with other pain complaints; and (4) to

  11. Transients drive the demographic dynamics of plant populations in variable environments

    DEFF Research Database (Denmark)

    McDonald, Jenni L; Stott, Iain; Townley, Stuart

    2016-01-01

    clear patterns related to growth form. We find a surprising tendency for plant populations to boom rather than bust in response to temporal changes in vital rates and that stochastic growth rates increase with increasing tendency to boom. Synthesis. Transient dynamics contribute significantly...

  12. Determination of hardiness by psychosocial and behavioural variables in a representative Czech population sample

    Czech Academy of Sciences Publication Activity Database

    Kebza, V.; Šolcová, Iva

    2008-01-01

    Roč. 23, Suppl. 1 (2008), s. 158 ISSN 0887-0446 R&D Projects: GA AV ČR(CZ) IAA 700250701 Institutional research plan: CEZ:AV0Z70250504 Keywords : hardiness * Czech population sample * social support Subject RIV: AN - Psychology

  13. Population pharmacokinetics and relationship between demographic and clinical variables and pharmacokinetics of gentamicin in neonates

    NARCIS (Netherlands)

    Stolk, L M L; Degraeuwe, P L J; Nieman, F H M; de Wolf, M C; de Boer, A|info:eu-repo/dai/nl/075097346

    Population pharmacokinetic parameter estimates were calculated from 725 routine plasma gentamicin concentrations obtained in 177 neonates of 24 to 42 weeks' gestational age in their first week of life. Kel increases and V/W decreases with increasing gestational age. Almost identical results were

  14. Genetic variability of CYP2C19 in a Mexican population: contribution ...

    Indian Academy of Sciences (India)

    poor metabolizer (PM) phenotype in a Mexican population sample (n = 238), as well as CYP2C19*17, unique allele ..... and environmental factors might influence the PM pheno- ... a relatively low health-care impact based on the predicted.

  15. Phenotypic variability of Rhodnius ecuadoriensis populations at the Ecuadorian central and southern Andean region.

    Science.gov (United States)

    Villacís, Anita G; Grijalva, Mario J; Catalá, Silvia S

    2010-11-01

    Rhodnius ecuadoriensis is an important vector of Chagas disease in Ecuador. Whereas only sylvatic and peridomestic populations are common in Manabi province, this species occupies domestic, peridomestic, and sylvatic habitats in Loja province where high reinfestation of houses was observed. To explore the existence of phenetic changes linked to the domiciliation of the species, this study set out to analyze the wing and antennal phenotypes of R. ecuadoriensis in these two provinces where the vector presents different affinity for domestic habitats. The antennal phenotype and the wing size and shape distinguish the two geographical populations of R. ecuadoriensis. In Manabí, sylvatic and peridomestic specimens were very similar. In Loja, sylvatic and nonsylvatic (domestic and peridomestic) populations showed distinctive characteristics. Remarkable sexual dimorphism of wing and antenna, exclusive of domestic specimens, and high metric disparity in the wing shape of the domestic females point out the existence of a particular situation in this habitat. The results of this phenotypic analysis and previous evidence of behavioral differences support the hypothesis of disruptive selection acting upon R. ecuadoriensis populations.

  16. Ecotype variability and edaphic characteristics for cogongrass (Imperata cylindrica) populations in Mississippi

    Science.gov (United States)

    Cogongrass (Imperata cylindrica) is a highly invasive perennial grass in the southeastern United States and is found on all continents except Antartica. It has been reported from a wide array of habitats; however, soils from cogongrass populations have never been characterized. Live cogongrass pla...

  17. Microsatellite variability in the entomopathogenic fungus Paeciolomyces fumosoroseus: genetic diversity and population structure

    Science.gov (United States)

    The hyphomycete Paecilomyces fumosoroseus (Pfr) is a geographically widespread fungus capable of infecting various insect hosts. The fungus has been used for the biological control of several important insect pests of agriculture. However knowledge of the fungus’ genetic diversity and population str...

  18. Variable Demographic Rates in an Invasive Plant Species: Differences Among Populations and Management Implications

    Science.gov (United States)

    Population managers are frequently faced with the challenge of selecting the most effective management strategy from a set of available strategies. In the case of classical weed biological control, this requires predicting a priori which of a group of candidate biocontrol agent species has the great...

  19. Variability and genetic structure of the population of watermelon mosaic virus infecting melon in Spain

    International Nuclear Information System (INIS)

    Moreno, I.M.; Malpica, J.M.; Diaz-Pendon, J.A.; Moriones, E.; Fraile, A.; Garcia-Arenal, F.

    2004-01-01

    The genetic structure of the population of Watermelon mosaic virus (WMV) in Spain was analysed by the biological and molecular characterisation of isolates sampled from its main host plant, melon. The population was a highly homogeneous one, built of a single pathotype, and comprising isolates closely related genetically. There was indication of temporal replacement of genotypes, but not of spatial structure of the population. Analyses of nucleotide sequences in three genomic regions, that is, in the cistrons for the P1, cylindrical inclusion (CI) and capsid (CP) proteins, showed lower similar values of nucleotide diversity for the P1 than for the CI or CP cistrons. The CI protein and the CP were under tighter evolutionary constraints than the P1 protein. Also, for the CI and CP cistrons, but not for the P1 cistron, two groups of sequences, defining two genetic strains, were apparent. Thus, different genomic regions of WMV show different evolutionary dynamics. Interestingly, for the CI and CP cistrons, sequences were clustered into two regions of the sequence space, defining the two strains above, and no intermediary sequences were identified. Recombinant isolates were found, accounting for at least 7% of the population. These recombinants presented two interesting features: (i) crossover points were detected between the analysed regions in the CI and CP cistrons, but not between those in the P1 and CI cistrons, (ii) crossover points were not observed within the analysed coding regions for the P1, CI or CP proteins. This indicates strong selection against isolates with recombinant proteins, even when originated from closely related strains. Hence, data indicate that genotypes of WMV, generated by mutation or recombination, outside of acceptable, discrete, regions in the evolutionary space, are eliminated from the virus population by negative selection

  20. Individual variability and mortality required for constant final yield in simulated plant populations

    Czech Academy of Sciences Publication Activity Database

    Fibich, P.; Lepš, Jan; Weiner, J.

    2014-01-01

    Roč. 7, č. 3 (2014), s. 263-271 ISSN 1874-1738 Grant - others:GA ČR(CZ) GA-1317118S; GA MŠk(CZ) LM2010005 Institutional support: RVO:60077344 Keywords : constant final yield * variability * mortality Subject RIV: EH - Ecology, Behaviour Impact factor: 1.553, year: 2014 http://link.springer.com/article/10.1007%2Fs12080-014-0216-x#

  1. Negative aging stereotypes and their relation with psychosocial variables in the elderly population.

    Science.gov (United States)

    Sánchez Palacios, C; Trianes Torres, M V; Blanca Mena, M J

    2009-01-01

    This study explores whether there is a relationship between the level of belief in negative aging stereotypes in 65-year-old people and their results concerning some psychosocial variables. These were selected for their relevance for health and well being in elderly people. These were: living situation, responsibilities toward others, subjective health, frequency of medical appointments, subjective age, participation in community social activities and regular physical activity. The sample consisted of 757 people of low educational level, ranged from 65 to 96 years. Age and gender were homogeneously distributed. Participants were non-institutionalized people. Firstly, the psychosocial variables under focus were assessed by means of seven questions. Secondly, a questionnaire about negative aging stereotypes (CENVE) was administered. It was composed of three factors: health, motivational-social and character-personality. Results show that a high score in negative stereotypes is significantly associated to the studied variables, except for living situation, showing a worse quality of life (QoL) profile. Results are discussed in terms of their utility for assessment and psychosocial intervention, which is meant to improve health in the elderly.

  2. Variable Isotopic Compositions of Host Plant Populations Preclude Assessment of Aphid Overwintering Sites

    Directory of Open Access Journals (Sweden)

    Michael S. Crossley

    2017-12-01

    Full Text Available Soybean aphid (Aphis glycines Matsumura is a pest of soybean in the northern Midwest whose migratory patterns have been difficult to quantify. Improved knowledge of soybean aphid overwintering sites could facilitate the development of control efforts with exponential impacts on aphid densities on a regional scale. In this preliminary study, we explored the utility of variation in stable isotopes of carbon and nitrogen to distinguish soybean aphid overwintering origins. We compared variation in bulk 13C and 15N content in buckthorn (Rhamnus cathartica L. and soybean aphids in Wisconsin, among known overwintering locations in the northern Midwest. Specifically, we looked for associations between buckthorn and environmental variables that could aid in identifying overwintering habitats. We detected significant evidence of correlation between the bulk 13C and 15N signals of soybean aphids and buckthorn, despite high variability in stable isotope composition within and among buckthorn plants. Further, the 15N signal in buckthorn varied predictably with soil composition. However, lack of sufficient differentiation of geographic areas along axes of isotopic and environmental variation appears to preclude the use of carbon and nitrogen isotopic signals as effective predictors of likely aphid overwintering sites. These preliminary data suggest the need for future work that can further account for variability in 13C and 15N within/among buckthorn plants, and that explores the utility of other stable isotopes in assessing likely aphid overwintering sites.

  3. Leukocyte Populations are Associated with Heart Rate Variability After a Triathlon

    Directory of Open Access Journals (Sweden)

    Cruz Germán Hernández

    2016-12-01

    Full Text Available The purpose of this study was to analyze cellular immune components and their association with heart rate variability in triathlon athletes. Twelve athletes were included (age 36.41 ± 5.57 years, body mass 81.84 ± 10.97 kg and blood samples were taken one week before, immediately, at 2 and 48 hours, and one week after competition. Total lymphocytes and their subpopulations, neutrophils, basophils, eosinophils and monocytes were analyzed. At the same time, heart rate variability was recorded for 30 minutes using Polar Team2®. A significant difference between lymphocyte subpopulations and heart rate variability was found in the different study periods. A positive correlation was found between total lymphocytes and rMSSD (r = .736, p <0.05, CD3+ and rMSSD (r = .785, p <0.05, and CD4+ and rMSSD (r = .795, p < 0.05 at the end of the competition. After one week of competition, a negative correlation was found between eosinophils and MRR, SDNN, pNN50, and rMSSD (p <0.01; and basophils and MRR, SDNN, pNN50, and rMSSD (p <0.01; while a positive correlation was found between CD19+ (B cells and pNN50 (r = .678, p <0.05. Our results suggest that it is possible to predict the effect of training with regard to the athlete's performance.

  4. Genetic variability and differentiation among populations of the Azorean endemic gymnosperm Juniperus brevifolia: baseline information for a conservation and restoration perspective.

    Science.gov (United States)

    Silva, Luís; Elias, Rui B; Moura, Mónica; Meimberg, Harald; Dias, Eduardo

    2011-12-01

    The Azorean endemic gymnosperm Juniperus brevifolia (Seub.) Antoine is a top priority species for conservation in Macaronesia, based on its ecological significance in natural plant communities. To evaluate genetic variability and differentiation among J. brevifolia populations from the Azorean archipelago, we studied 15 ISSR and 15 RAPD markers in 178 individuals from 18 populations. The average number of polymorphic bands per population was 65 for both ISSR and RAPD. The majority of genetic variability was found within populations and among populations within islands, and this partitioning of variability was confirmed by AMOVA. The large majority of population pairwise F(ST) values were above 0.3 and below 0.6. The degree of population genetic differentiation in J. brevifolia was relatively high compared with other species, including Juniperus spp. The genetic differentiation among populations suggests that provenance should be considered when formulating augmentation or reintroduction strategies.

  5. Population dynamics and in vitro antibody pressure of porcine parvovirus indicate a decrease in variability.

    Science.gov (United States)

    Streck, André Felipe; Homeier, Timo; Foerster, Tessa; Truyen, Uwe

    2013-09-01

    To estimate the impact of porcine parvovirus (PPV) vaccines on the emergence of new phenotypes, the population dynamic history of the virus was calculated using the Bayesian Markov chain Monte Carlo method with a Bayesian skyline coalescent model. Additionally, an in vitro model was performed with consecutive passages of the 'Challenge' strain (a virulent field strain) and NADL2 strain (a vaccine strain) in a PK-15 cell line supplemented with polyclonal antibodies raised against the vaccine strain. A decrease in genetic diversity was observed in the presence of antibodies in vitro or after vaccination (as estimated by the in silico model). We hypothesized that the antibodies induced a selective pressure that may reduce the incidence of neutral selection, which should play a major role in the emergence of new mutations. In this scenario, vaccine failures and non-vaccinated populations (e.g. wild boars) may have an important impact in the emergence of new phenotypes.

  6. [Geographic variability of Adh-F allele frequency in populations of Drosophila melanogaster].

    Science.gov (United States)

    Bubliĭ, O A; Imasheva, A G

    1997-07-01

    Variation of Adh-F allele frequency in seven regions of North and South America, Eurasia, Africa, and Australia was analyzed on the basis of published data. In six regions, regression of Adh-F frequency on latitude was positive; in four regions, slopes of the regression curves were identical. Regression on the average lowest temperature of the coldest month was negative in six regions. No definite trends in regression on the highest temperature of the hottest month and on rainfall in the most humid month and the driest months were found. Geographic differentiation of populations was independent of climatic parameters. Examination of variation in various climatic zones revealed that tropical populations were distinctly different from those from other climatic zones. No climatic differentiation of fixation index FST was detected. These results indicate that Adh polymorphism is maintained by natural selection.

  7. The Relationship Between Pedometer-Determined Ambulatory Activity and Balance Variables Within an Older Adult Population

    OpenAIRE

    Campbell, Candice; Kress, Jeff; Schroeder, Jan; Donlin, Ayla; Rozenek, Ralph

    2016-01-01

    The purpose of this investigation was to determine the differences between gender, physical activity level, and balance in an older adult population. A secondary purpose was to examine the relationship between pedometer-determined ambulatory activity and balance. Forty-six older adults aged 73.7 ± 6.2 years participated in the study. Participants completed the Fullerton Advanced Balance (FAB) Scale and completed a 2-week daily step recording to determine average steps taken per day. Low-level...

  8. Genetic variability within the Polish population of red fox (Vulpes vulpes – preliminary results

    Directory of Open Access Journals (Sweden)

    Magdalena Zatoń-Dobrowolska

    2016-09-01

    Full Text Available Red fox (Vulpes vulpes represents family Canidae and is a very common predator in Poland. Foxes are present throughout all the country in a different geographical regions and habitats. The analyzed dataset consisted of 130 red foxes (Vulpes vulpes. There were 24 microsatellite sequences studied. The observed (HO and expected (HS heterozygosities were comparable within respective loci. The low genetic diversity of the population was found.

  9. Supplemental Dietary Inulin of Variable Chain Lengths Alters Intestinal Bacterial Populations in Young Pigs123

    Science.gov (United States)

    Patterson, Jannine K.; Yasuda, Koji; Welch, Ross M.; Miller, Dennis D.; Lei, Xin Gen

    2010-01-01

    Previously, we showed that supplementation of diets with short-chain inulin (P95), long-chain inulin (HP), and a 50:50 mixture of both (Synergy 1) improved body iron status and altered expression of the genes involved in iron homeostasis and inflammation in young pigs. However, the effects of these 3 types of inulin on intestinal bacteria remain unknown. Applying terminal restriction fragment length polymorphism analysis, we determined the abundances of luminal and adherent bacterial populations from 6 segments of the small and large intestines of pigs (n = 4 for each group) fed an iron-deficient basal diet (BD) or the BD supplemented with 4% of P95, Synergy 1, or HP for 5 wk. Compared with BD, all 3 types of inulin enhanced (P inulin on bacterial populations in the lumen contents were found. Meanwhile, all 3 types of inulin suppressed the less desirable bacteria Clostridium spp. and members of the Enterobacteriaceae in the lumen and mucosa of various gut segments. Our findings suggest that the ability of dietary inulin to alter intestinal bacterial populations may partially account for its iron bioavailability-promoting effect and possibly other health benefits. PMID:20980641

  10. Variability in DNA repair capacity in the human population and its relationship to carcinogenic risk

    International Nuclear Information System (INIS)

    Nuzzo, F.; Stefanini, M.; Giulotto, E.; Falaschi, A.

    1980-01-01

    Several inherited diseases, all characterized by a high incidence of tumours in the homozygous patients, show pronounced defects in DNA repair mechanisms, thus confirming the relationship between the repair process and mutation induction, and indicating clearly that a fraction of the population is certainly much more exposed to cancer that the bulk of the human population. The basic molecular defects in such diseases are summarized. The estimated heterozygote frequency in tumour predisposing syndromes is considered and possible identification of heterozygotes discussed. A procedure to reveal DNA repair capacity at the cellular level would perhaps identify the cancer-prone fraction of the population. A simple assay for measuring repair synthesis is outlined which can be used to determine whether a given substance or treatment elicits repair synthesis and is hence harmful to DNA and potentially mutagenic and/or carcinogenic. It can also be used to assess the capacity of an individual to respond to a known DNA damaging agent. (Auth./C.F.)

  11. Genetic variability among populations of Lutzomyia (Psathyromyia) shannoni (Dyar 1929) (Diptera: Psychodidae: Phlebotominae) in Colombia.

    Science.gov (United States)

    Cárdenas, E; Munstermann, L E; Martínez, O; Corredor, D; Ferro, C

    2001-02-01

    Polyacrylamide gel electrophoresis was used to elucidate genetic variation at 13 isozyme loci among forest populations of Lutzomyia shannoni from three widely separated locations in Colombia: Palambí (Nariño Department), Cimitarra (Santander Department) and Chinácota (Norte de Santander Department). These samples were compared with a laboratory colony originating from the Magdalena Valley in Central Colombia. The mean heterozygosity ranged from 16 to 22%, with 2.1 to 2.6 alleles detected per locus. Nei's genetic distances among populations were low, ranging from 0.011 to 0.049. The estimated number of migrants (Nm=3.8) based on Wright's F-Statistic, F ST, indicated low levels of gene flow among Lu. shannoni forest populations. This low level of migration indicates that the spread of stomatitis virus occurs via infected host, not by infected insect. In the colony sample of 79 individuals, the Gpi locus was homozygotic (0.62/0.62) in all females and heterozygotic (0.62/0.72) in all males. Although this phenomenon is probably a consequence of colonization, it indicates that Gpi is linked to a sex determining locus.

  12. Genetic variability among populations of Lutzomyia (Psathyromyia shannoni (Dyar 1929 (Diptera: Psychodidae: Phlebotominae in Colombia

    Directory of Open Access Journals (Sweden)

    Cárdenas Estrella

    2001-01-01

    Full Text Available Polyacrylamide gel electrophoresis was used to elucidate genetic variation at 13 isozyme loci among forest populations of Lutzomyia shannoni from three widely separated locations in Colombia: Palambí (Nariño Department, Cimitarra (Santander Department and Chinácota (Norte de Santander Department. These samples were compared with a laboratory colony originating from the Magdalena Valley in Central Colombia. The mean heterozygosity ranged from 16 to 22%, with 2.1 to 2.6 alleles detected per locus. Nei's genetic distances among populations were low, ranging from 0.011 to 0.049. The estimated number of migrants (Nm=3.8 based on Wright's F-Statistic, F ST, indicated low levels of gene flow among Lu. shannoni forest populations. This low level of migration indicates that the spread of stomatitis virus occurs via infected host, not by infected insect. In the colony sample of 79 individuals, the Gpi locus was homozygotic (0.62/0.62 in all females and heterozygotic (0.62/0.72 in all males. Although this phenomenon is probably a consequence of colonization, it indicates that Gpi is linked to a sex determining locus.

  13. Consequences of an uncertain mass mortality regime triggered by climate variability on giant clam population management in the Pacific Ocean.

    Science.gov (United States)

    Van Wynsberge, Simon; Andréfouët, Serge; Gaertner-Mazouni, Nabila; Remoissenet, Georges

    2018-02-01

    Despite actions to manage sustainably tropical Pacific Ocean reef fisheries, managers have faced failures and frustrations because of unpredicted mass mortality events triggered by climate variability. The consequences of these events on the long-term population dynamics of living resources need to be better understood for better management decisions. Here, we use a giant clam (Tridacna maxima) spatially explicit population model to compare the efficiency of several management strategies under various scenarios of natural mortality, including mass mortality due to climatic anomalies. The model was parameterized by in situ estimations of growth and mortality and fishing effort, and was validated by historical and new in situ surveys of giant clam stocks in two French Polynesia lagoons. Projections on the long run (100 years) suggested that the best management strategy was a decrease of fishing pressure through quota implementation, regardless of the mortality regime considered. In contrast, increasing the minimum legal size of catch and closing areas to fishing were less efficient. When high mortality occurred due to climate variability, the efficiency of all management scenarios decreased markedly. Simulating El Niño Southern Oscillation event by adding temporal autocorrelation in natural mortality rates increased the natural variability of stocks, and also decreased the efficiency of management. These results highlight the difficulties that managers in small Pacific islands can expect in the future in the face of global warming, climate anomalies and new mass mortalities. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Breeding biology and variable mating system of a population of introduced dunnocks (Prunella modularis in New Zealand.

    Directory of Open Access Journals (Sweden)

    Eduardo S A Santos

    Full Text Available Species with variable mating systems provide a unique opportunity to investigate whether females receive direct fitness benefits from additional male partners. The direct benefits provide an obvious explanation for why females would breed polyandrously, in a situation where males clearly do not attain their optimal reproductive success. Evidence for these direct benefits is, however, mixed. Here, we present a detailed study of the breeding biology of the dunnock, Prunella modularis, which inform an investigation into the effects of the social mating system on the reproductive success in a population of dunnocks in Southern New Zealand. We studied 80 different social groups over the course of three breeding seasons. Dunnocks in our population presented a variable mating system, with socially monogamous (45%, socially polyandrous (54% and socially polygynandrous (1% groups being observed in the same breeding season. We did not observe any polygynous social units in our study period although polygyny exists in the population. We found little difference in the numbers of eggs laid, and egg volume between monogamous and polyandrous nests. However, polyandrous groups had better hatching and fledging success than monogamous groups (composite d = 0.385, 95% CI: 0.307 to 0.463. Overall our results support the notion that polyandry is beneficial for females.

  15. Hydrologic variability governs population dynamics of a vulnerable amphibian in an arid environment.

    Directory of Open Access Journals (Sweden)

    Erin R Zylstra

    Full Text Available Dynamics of many amphibian populations are governed by the distribution and availability of water. Therefore, understanding the hydrological mechanisms that explain spatial and temporal variation in occupancy and abundance will improve our ability to conserve and recover populations of vulnerable amphibians. We used 16 years of survey data from intermittent mountain streams in the Sonoran Desert to evaluate how availability of surface water affected survival and adult recruitment of a threatened amphibian, the lowland leopard frog (Lithobates yavapaiensis. Across the entire study period, monthly survival of adults ranged from 0.72 to 0.99 during summer and 0.59 to 0.94 during winter and increased with availability of surface water (Z = 7.66; P < 0.01. Recruitment of frogs into the adult age class occurred primarily during winter and ranged from 1.9 to 3.8 individuals/season/pool; like survival, recruitment increased with availability of surface water (Z = 3.67; P < 0.01. Although abundance of frogs varied across seasons and years, we found no evidence of a systematic trend during the 16-year study period. Given the strong influence of surface water on population dynamics of leopard frogs, conservation of many riparian obligates in this and similar arid regions likely depends critically on minimizing threats to structures and ecosystem processes that maintain surface waters. Understanding the influence of surface-water availability on riparian organisms is particularly important because climate change is likely to decrease precipitation and increase ambient temperatures in desert riparian systems, both of which have the potential to alter fundamentally the hydrology of these systems.

  16. Environmental pollution, climate variability and climate change: a review of health impacts on the peruvian population

    OpenAIRE

    Gonzales, Gustavo F.; Instituto de Investigaciones de la Altura. Lima, Perú. Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia. Lima, Perú. Academia Nacional de Ciencias. Lima, Perú. Doctor en Ciencias y doctor en Medicina; Zevallos, Alisson; Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia. Lima, Perú. estudiante de Biología; Gonzales-Castañeda, Cynthia; Instituto de Investigaciones de la Altura. Lima, Perú. Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia. Lima, Perú. Philosophal Doctor; Nuñez, Denisse; Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia. Lima, Perú. estudiante de Biología; Gastañaga, Carmen; Instituto Nacional de Salud. Lima, Perú. médico cirujano; Cabezas, César; Instituto Nacional de Salud. Lima, Perú. médico infectólogo; Naeher, Luke; University of Georgia. Georgia, EE. UU. Philosophal Doctor; Levy, Karen; University of Emory. Georgia. EE. UU. Philosophal Doctor; Steenlan, Kyle; University of Emory. Georgia. EE. UU. Philosophal Doctor

    2014-01-01

    This article is a review of the pollution of water, air and the effect of climate change on the health of the Peruvian population. A major air pollutant is particulate matter less than 2.5 μ (PM 2.5). In Lima, 2,300 premature deaths annually are attributable to this pollutant. Another problem is household air pollution by using stoves burning biomass fuels, where excessive indoor exposure to PM 2.5 inside the household is responsible for approximately 3,000 annual premature deaths among adult...

  17. Population variability of triple symbiotic system: Paramecium bursaria-zoochlorella-and algophages

    Directory of Open Access Journals (Sweden)

    Konstantin V Kvitko

    2004-12-01

    Full Text Available The triple symbiotic system (TSS: P. bursaria-Chlorella-Chlorovirus, was studied. In Eurasia we found only 2 forms TSS, named N, northern and S, southern ecotypes. Each ecotype manifested at 32°C ts (N-or tr (S-phenotypes. In northeren parts of P. bursaria areals, from Karelia up to Kamchatka, near Baikal and in Armenia highlands, we find only ts-viruses, in Central Asia - only tr-types. Two types of genome characters were shown by PCR of 18 S RNA-genes. According all this characters populations of zoochlorella in P. bursaria - 2 clones of obligate symbionts

  18. [GENETIC VARIABILITY OF MATERNAL PLANTS AND SEED EMBRYOS OF KOCH PINE POPULATIONS (PINUS KOCHIANA KLOTZSCH EX KOCH) IN CRIMEA].

    Science.gov (United States)

    Korshykov, I I; Kalafat, L O; Vynogradova, O M; Podgornyi, D Y

    2016-01-01

    Comparative studies of genetic variability were undertaken for 12 allozyme loci selections of trees and embryos of seed, and also for the crossing systems in five populations of Koch pine of (Pinus kochiana Klotzsch ex Koch) in Crimea. It was shown that in seed embryos the allelic variety peculiar to the maternal plants was restored, however the level of the available (H₀) heterozygosity was considerably lower, 0.286 and 0.189 respectively. For the embryos unlike the trees, in the majority of the analyzed loci the considerable divergence was specific in the actual distribution of genotypes from the theoretically expected according to Hardy- Weinberg law. The proportion of cross pollination at the unilocal (t(s)) estimation varied from 0.384 to 0.673 in the populations, while at the multilocal ones (t(m)) it was 0.639-0.841.

  19. Population Density, Climate Variables and Poverty Synergistically Structure Spatial Risk in Urban Malaria in India.

    Science.gov (United States)

    Santos-Vega, Mauricio; Bouma, Menno J; Kohli, Vijay; Pascual, Mercedes

    2016-12-01

    The world is rapidly becoming urban with the global population living in cities projected to double by 2050. This increase in urbanization poses new challenges for the spread and control of communicable diseases such as malaria. In particular, urban environments create highly heterogeneous socio-economic and environmental conditions that can affect the transmission of vector-borne diseases dependent on human water storage and waste water management. Interestingly India, as opposed to Africa, harbors a mosquito vector, Anopheles stephensi, which thrives in the man-made environments of cities and acts as the vector for both Plasmodium vivax and Plasmodium falciparum, making the malaria problem a truly urban phenomenon. Here we address the role and determinants of within-city spatial heterogeneity in the incidence patterns of vivax malaria, and then draw comparisons with results for falciparum malaria. Statistical analyses and a phenomenological transmission model are applied to an extensive spatio-temporal dataset on cases of Plasmodium vivax in the city of Ahmedabad (Gujarat, India) that spans 12 years monthly at the level of wards. A spatial pattern in malaria incidence is described that is largely stationary in time for this parasite. Malaria risk is then shown to be associated with socioeconomic indicators and environmental parameters, temperature and humidity. In a more dynamical perspective, an Inhomogeneous Markov Chain Model is used to predict vivax malaria risk. Models that account for climate factors, socioeconomic level and population size show the highest predictive skill. A comparison to the transmission dynamics of falciparum malaria reinforces the conclusion that the spatio-temporal patterns of risk are strongly driven by extrinsic factors. Climate forcing and socio-economic heterogeneity act synergistically at local scales on the population dynamics of urban malaria in this city. The stationarity of malaria risk patterns provides a basis for more

  20. Population Density, Climate Variables and Poverty Synergistically Structure Spatial Risk in Urban Malaria in India.

    Directory of Open Access Journals (Sweden)

    Mauricio Santos-Vega

    2016-12-01

    Full Text Available The world is rapidly becoming urban with the global population living in cities projected to double by 2050. This increase in urbanization poses new challenges for the spread and control of communicable diseases such as malaria. In particular, urban environments create highly heterogeneous socio-economic and environmental conditions that can affect the transmission of vector-borne diseases dependent on human water storage and waste water management. Interestingly India, as opposed to Africa, harbors a mosquito vector, Anopheles stephensi, which thrives in the man-made environments of cities and acts as the vector for both Plasmodium vivax and Plasmodium falciparum, making the malaria problem a truly urban phenomenon. Here we address the role and determinants of within-city spatial heterogeneity in the incidence patterns of vivax malaria, and then draw comparisons with results for falciparum malaria.Statistical analyses and a phenomenological transmission model are applied to an extensive spatio-temporal dataset on cases of Plasmodium vivax in the city of Ahmedabad (Gujarat, India that spans 12 years monthly at the level of wards. A spatial pattern in malaria incidence is described that is largely stationary in time for this parasite. Malaria risk is then shown to be associated with socioeconomic indicators and environmental parameters, temperature and humidity. In a more dynamical perspective, an Inhomogeneous Markov Chain Model is used to predict vivax malaria risk. Models that account for climate factors, socioeconomic level and population size show the highest predictive skill. A comparison to the transmission dynamics of falciparum malaria reinforces the conclusion that the spatio-temporal patterns of risk are strongly driven by extrinsic factors.Climate forcing and socio-economic heterogeneity act synergistically at local scales on the population dynamics of urban malaria in this city. The stationarity of malaria risk patterns provides a

  1. Association of Climatic Variability, Vector Population and Malarial Disease in District of Visakhapatnam, India: A Modeling and Prediction Analysis.

    Science.gov (United States)

    Srimath-Tirumula-Peddinti, Ravi Chandra Pavan Kumar; Neelapu, Nageswara Rao Reddy; Sidagam, Naresh

    2015-01-01

    Malarial incidence, severity, dynamics and distribution of malaria are strongly determined by climatic factors, i.e., temperature, precipitation, and relative humidity. The objectives of the current study were to analyse and model the relationships among climate, vector and malaria disease in district of Visakhapatnam, India to understand malaria transmission mechanism (MTM). Epidemiological, vector and climate data were analysed for the years 2005 to 2011 in Visakhapatnam to understand the magnitude, trends and seasonal patterns of the malarial disease. Statistical software MINITAB ver. 14 was used for performing correlation, linear and multiple regression analysis. Perennial malaria disease incidence and mosquito population was observed in the district of Visakhapatnam with peaks in seasons. All the climatic variables have a significant influence on disease incidence as well as on mosquito populations. Correlation coefficient analysis, seasonal index and seasonal analysis demonstrated significant relationships among climatic factors, mosquito population and malaria disease incidence in the district of Visakhapatnam, India. Multiple regression and ARIMA (I) models are best suited models for modeling and prediction of disease incidences and mosquito population. Predicted values of average temperature, mosquito population and malarial cases increased along with the year. Developed MTM algorithm observed a major MTM cycle following the June to August rains and occurring between June to September and minor MTM cycles following March to April rains and occurring between March to April in the district of Visakhapatnam. Fluctuations in climatic factors favored an increase in mosquito populations and thereby increasing the number of malarial cases. Rainfall, temperatures (20°C to 33°C) and humidity (66% to 81%) maintained a warmer, wetter climate for mosquito growth, parasite development and malaria transmission. Changes in climatic factors influence malaria directly by

  2. The Relationship Between Pedometer-Determined Ambulatory Activity and Balance Variables Within an Older Adult Population.

    Science.gov (United States)

    Campbell, Candice; Kress, Jeff; Schroeder, Jan; Donlin, Ayla; Rozenek, Ralph

    2016-01-01

    The purpose of this investigation was to determine the differences between gender, physical activity level, and balance in an older adult population. A secondary purpose was to examine the relationship between pedometer-determined ambulatory activity and balance. Forty-six older adults aged 73.7 ± 6.2 years participated in the study. Participants completed the Fullerton Advanced Balance (FAB) Scale and completed a 2-week daily step recording to determine average steps taken per day. Low-level activity participants (7,500 steps/day) in weight, age, and the number of medications reported. Males performed better than females on the two-footed jump test and reactive postural test FAB assessments. High-level activity participants performed significantly better than low-level activity participants on all FAB assessments except stand with feet together and eyes closed, reach forward to object, and walk with head turns.

  3. The Relationship Between Pedometer-Determined Ambulatory Activity and Balance Variables Within an Older Adult Population

    Directory of Open Access Journals (Sweden)

    Candice Campbell MS

    2016-12-01

    Full Text Available The purpose of this investigation was to determine the differences between gender, physical activity level, and balance in an older adult population. A secondary purpose was to examine the relationship between pedometer-determined ambulatory activity and balance. Forty-six older adults aged 73.7 ± 6.2 years participated in the study. Participants completed the Fullerton Advanced Balance (FAB Scale and completed a 2-week daily step recording to determine average steps taken per day. Low-level activity participants (7,500 steps/day in weight, age, and the number of medications reported. Males performed better than females on the two-footed jump test and reactive postural test FAB assessments. High-level activity participants performed significantly better than low-level activity participants on all FAB assessments except stand with feet together and eyes closed, reach forward to object, and walk with head turns.

  4. Contribution of insertions and deletions to the variability of hepatitis C virus populations.

    Science.gov (United States)

    Torres-Puente, Manuela; Cuevas, José M; Jiménez-Hernández, Nuria; Bracho, María A; García-Robles, Inmaculada; Carnicer, Fernando; del Olmo, Juan; Ortega, Enrique; Moya, Andrés; González-Candelas, Fernando

    2007-08-01

    Little is known about the potential effects of insertions and deletions (indels) on the evolutionary dynamics of hepatitis C virus (HCV). In fact, the consequences of indels on antiviral treatment response are a field of investigation completely unexplored. Here, an extensive sequencing project was undertaken by cloning and sequencing serum samples from 25 patients infected with HCV subtype 1a and 48 patients with subtype 1b. For 23 patients, samples obtained after treatment with alpha interferon plus ribavirin were also available. Two genome fragments containing the hypervariable regions in the envelope 2 glycoprotein and the PKR-BD domain in NS5A were sequenced, yielding almost 16 000 sequences. Our results show that insertions are quite rare, but they are often present in biologically relevant domains of the HCV genome. Moreover, their frequency distributions between different time samples reflect the quasispecies dynamics of HCV populations. Deletions seem to be subject to negative selection.

  5. The effect of clumped population structure on the variability of spreading dynamics.

    Science.gov (United States)

    Black, Andrew J; House, Thomas; Keeling, Matt J; Ross, Joshua V

    2014-10-21

    Processes that spread through local contact, including outbreaks of infectious diseases, are inherently noisy, and are frequently observed to be far noisier than predicted by standard stochastic models that assume homogeneous mixing. One way to reproduce the observed levels of noise is to introduce significant individual-level heterogeneity with respect to infection processes, such that some individuals are expected to generate more secondary cases than others. Here we consider a population where individuals can be naturally aggregated into clumps (subpopulations) with stronger interaction within clumps than between them. This clumped structure induces significant increases in the noisiness of a spreading process, such as the transmission of infection, despite complete homogeneity at the individual level. Given the ubiquity of such clumped aggregations (such as homes, schools and workplaces for humans or farms for livestock) we suggest this as a plausible explanation for noisiness of many epidemic time series. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Biological variability of the minutiae in the fingerprints of a sample of the Spanish population.

    Science.gov (United States)

    Gutiérrez, Esperanza; Galera, Virginia; Martínez, Jose Manuel; Alonso, Concepción

    2007-10-25

    The minutiae, a term coined by Galton to refer to the small peculiarities present along the length of every isolated ridge, or characteristic points, a term used primarily by the Spanish Police Scientists, have an inter- and intrapopulation variability which has not been extensively studied. However, these peculiarities constitute the bases for the fingerprint identification of individuals in the field of criminology. Using the adhesive paper and graphite method, the fingerprints of 200 students, 100 males and 100 females, with ages ranging between 20 and 35, have been taken at the University of Alcala (Madrid). From this sample, the distal phalanx of the index finger of the right hand has been studied. The total count of the minutiae, as well as that of each different type, was made of the entire print area, and inside and outside of a circle with a radius of 18 ridges. The highest frequencies were of ridge endings, followed by bifurcations and convergences, all others appearing with frequencies of lower than 5%. The distribution of the minutiae was not homogeneous for the area of the fingerprint (inside and outside the circle). In the study of minutiae statistically significant differences were found between the sexes, and between the different types of general pattern (arches, loops, and whorls).

  7. Social psychological variables in populations contrasted by income and suicide rate: Durkheim revisited.

    Science.gov (United States)

    Ferrada-Noli, M

    1997-08-01

    The ten richest and ten poorest municipalities of Sweden were investigated with respect to national statistics to assess the relationship between suicide incidence, discrete social psychological variables associated with welfare admittance among the elderly, and income of municipality. The relative frequency of suicide was 1.6 times greater for Swedes from the low-income municipalities than for those from the high-income ones. The group of municipalities with the highest suicide rate had a significantly higher proportion of older people in need of municipal social assistance at their homes and also a significantly higher proportion of elderly living in municipality-managed 'service-homes.' The findings replicate earlier investigations and suggest social psychological indicators denoting less favourable economic and social resources are also associated with both an increased suicide rate and a decreased county or municipal income. Some theoretical issues of the socioeconomic and of the external restraint hypotheses of the incidence of suicide, contradicted by the present findings as well as of Durkheim's hypothesis of social control are discussed. Further, we suggest the consideration of negative socioeconomic conditions as a risk factor amid psychiatric clinical assessments of risk for suicidal behaviour.

  8. Principles that underpin effective school-based drug education.

    Science.gov (United States)

    Midford, Richard; Munro, Geoffrey; McBride, Nyanda; Snow, Pamela; Ladzinski, Ursula

    2002-01-01

    This study identifies the conceptual underpinnings of effective school-based drug education practice in light of contemporary research evidence and the practical experience of a broad range of drug education stakeholders. The research involved a review of the literature, a national survey of 210 Australian teachers and others involved in drug education, and structured interviews with 22 key Australian drug education policy stakeholders. The findings from this research have been distilled and presented as a list of 16 principles that underpin effective drug education. In broad terms, drug education should be evidence-based, developmentally appropriate, sequential, and contextual. Programs should be initiated before drug use commences. Strategies should be linked to goals and should incorporate harm minimization. Teaching should be interactive and use peer leaders. The role of the classroom teacher is central. Certain program content is important, as is social and resistance skills training. Community values, the social context of use, and the nature of drug harm have to be addressed. Coverage needs to be adequate and supported by follow-up. It is envisaged that these principles will provide all those involved in the drug education field with a set of up-to-date, research-based guidelines against which to reference decisions on program design, selection, implementation, and evaluation.

  9. CHEMICAL COMPOSITION VARIABILITY IN THE Uncaria tomentosa (cat’s claw WILD POPULATION

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    Evelyn Maribel Condori Peñaloza

    2015-03-01

    Full Text Available Uncaria tomentosa (cat's claw is a vine widely distributed throughout the South-American rainforest. Many studies investigating the chemical composition of cat's claw have focused on the pentacyclic (POA and tetracyclic oxindole alkaloids (TOA, quinovic acid glycosides (QAG, and polyphenols (PPH. Nevertheless, it is still uncertain how environmental factors affect chemical groups. The aim of this work was to better understand the influence of environmental factors (geographic origin, altitude, and season on cat's claw chemical composition. Stem bark, branches and leaf samples were extracted and analyzed by HPLC-PDA. The data obtained were explored by multivariate analysis (HCA and PCA. Higher amounts of oxindole alkaloids and PPH were found in leaves, followed by stem bark and branches. No clear relationship was verified among geographic origin or altitude and chemical composition, which remained unchanged regardless of season (dry or rainy. However, three oxindole alkaloid chemotypes were clearly recognized: chemotype I (POA with cis D/E ring junction; chemotype II (POA with trans D/E ring junction; and chemotype III (TOA. Thus, environmental factors appear to have only a minor influence on the chemical heterogeneity of the cat's claw wild population. Nevertheless, the occurrence of different chemotypes based on alkaloid profiles seems to be clear.

  10. [Environmental pollution, climate variability and climate change: a review of health impacts on the Peruvian population].

    Science.gov (United States)

    Gonzales, Gustavo F; Zevallos, Alisson; Gonzales-Castañeda, Cynthia; Nuñez, Denisse; Gastañaga, Carmen; Cabezas, César; Naeher, Luke; Levy, Karen; Steenland, Kyle

    2014-01-01

    This article is a review of the pollution of water, air and the effect of climate change on the health of the Peruvian population. A major air pollutant is particulate matter less than 2.5 μ (PM 2.5). In Lima, 2,300 premature deaths annually are attributable to this pollutant. Another problem is household air pollution by using stoves burning biomass fuels, where excessive indoor exposure to PM 2.5 inside the household is responsible for approximately 3,000 annual premature deaths among adults, with another unknown number of deaths among children due to respiratory infections. Water pollution is caused by sewage discharges into rivers, minerals (arsenic) from various sources, and failure of water treatment plants. In Peru, climate change may impact the frequency and severity of El Niño Southern Oscillation (ENSO), which has been associated with an increase in cases of diseases such as cholera, malaria and dengue. Climate change increases the temperature and can extend the areas affected by vector-borne diseases, have impact on the availability of water and contamination of the air. In conclusion, Peru is going through a transition of environmental risk factors, where traditional and modern risks coexist and infectious and chronic problems remain, some of which are associated with problems of pollution of water and air.

  11. High Levels of Genetic Diversity of Plasmodium falciparum Populations in Papua New Guinea despite Variable Infection Prevalence

    Science.gov (United States)

    Barry, Alyssa E.; Schultz, Lee; Senn, Nicholas; Nale, Joe; Kiniboro, Benson; Siba, Peter M.; Mueller, Ivo; Reeder, John C.

    2013-01-01

    High levels of genetic diversity in Plasmodium falciparum populations are an obstacle to malaria control. Here, we investigate the relationship between local variation in malaria epidemiology and parasite genetic diversity in Papua New Guinea (PNG). Cross-sectional malaria surveys were performed in 14 villages spanning four distinct malaria-endemic areas on the north coast, including one area that was sampled during the dry season. High-resolution msp2 genotyping of 2,147 blood samples identified 761 P. falciparum infections containing a total of 1,392 clones whose genotypes were used to measure genetic diversity. Considerable variability in infection prevalence and mean multiplicity of infection was observed at all of the study sites, with the area sampled during the dry season showing particularly striking local variability. Genetic diversity was strongly associated with multiplicity of infection but not with infection prevalence. In highly endemic areas, differences in infection prevalence may not translate into a decrease in parasite population diversity. PMID:23400571

  12. Demographic variables, clinical aspects, and medicolegal implications in a population of patients with adjustment disorder.

    Science.gov (United States)

    Anastasia, Annalisa; Colletti, Chiara; Cuoco, Valentina; Quartini, Adele; Urso, Stefania; Rinaldi, Raffaella; Bersani, Giuseppe

    2016-01-01

    Although adjustment disorder (AD) is considered as residual diagnosis and receives little attention in research, it plays an important role in clinical practice and also assumes an increasingly important role in the field of legal medicine, where the majority of diagnostic frameworks (eg, mobbing) often refer to AD. Our study aimed to look for specific stressor differences among demographic and clinical variables in a naturalistic setting of patients with AD. A restrospective statistical analysis of the data of patients diagnosed with AD from November 2009 to September 2012, identified via manual search from the archive of the outpatient setting at the University Unit of Psychiatry "A. Fiorini" Hospital, Terracina (Latina, Italy), was performed. The sample consisted of 93 patients (46 males and 47 females), aged between 26 and 85, with medium-high educational level who were mainly employed. In most cases (54.80%), a diagnosis of AD with mixed anxiety and depressed mood was made. In all, 72% of the sample reported a negative family history for psychiatric disorders. In 22.60%, a previous history of psychopathology, especially mood disorders (76.19%), was reported. The main stressors linked to the development of AD were represented by working problems (32.30%), family problems (23.70%), and/or somatic disease (22.60%) with significant differences with respect to age and sex. Half of the patients were subjected to a single first examination; 24.47% requested a copy of medical records. Confirming previous data from previous reports, our results suggest that AD may have a distinct profile in demographic and clinical terms. Increased scientific attention is hoped, particularly focused on addressing a better definition of diagnostic criteria, whose correctness and accuracy are critical, especially in situations with medicolegal implications.

  13. Brucella Genetic Variability in Wildlife Marine Mammals Populations Relates to Host Preference and Ocean Distribution.

    Science.gov (United States)

    Suárez-Esquivel, Marcela; Baker, Kate S; Ruiz-Villalobos, Nazareth; Hernández-Mora, Gabriela; Barquero-Calvo, Elías; González-Barrientos, Rocío; Castillo-Zeledón, Amanda; Jiménez-Rojas, César; Chacón-Díaz, Carlos; Cloeckaert, Axel; Chaves-Olarte, Esteban; Thomson, Nicholas R; Moreno, Edgardo; Guzmán-Verri, Caterina

    2017-07-01

    Intracellular bacterial pathogens probably arose when their ancestor adapted from a free-living environment to an intracellular one, leading to clonal bacteria with smaller genomes and less sources of genetic plasticity. Still, this plasticity is needed to respond to the challenges posed by the host. Members of the Brucella genus are facultative-extracellular intracellular bacteria responsible for causing brucellosis in a variety of mammals. The various species keep different host preferences, virulence, and zoonotic potential despite having 97-99% similarity at genome level. Here, we describe elements of genetic variation in Brucella ceti isolated from wildlife dolphins inhabiting the Pacific Ocean and the Mediterranean Sea. Comparison with isolates obtained from marine mammals from the Atlantic Ocean and the broader Brucella genus showed distinctive traits according to oceanic distribution and preferred host. Marine mammal isolates display genetic variability, represented by an important number of IS711 elements as well as specific IS711 and SNPs genomic distribution clustering patterns. Extensive pseudogenization was found among isolates from marine mammals as compared with terrestrial ones, causing degradation in pathways related to energy, transport of metabolites, and regulation/transcription. Brucella ceti isolates infecting particularly dolphin hosts, showed further degradation of metabolite transport pathways as well as pathways related to cell wall/membrane/envelope biogenesis and motility. Thus, gene loss through pseudogenization is a source of genetic variation in Brucella, which in turn, relates to adaptation to different hosts. This is relevant to understand the natural history of bacterial diseases, their zoonotic potential, and the impact of human interventions such as domestication. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  14. Detailed analysis of the microbial population in Malaysian spontaneous cocoa pulp fermentations reveals a core and variable microbiota.

    Directory of Open Access Journals (Sweden)

    Esther Meersman

    Full Text Available The fermentation of cocoa pulp is one of the few remaining large-scale spontaneous microbial processes in today's food industry. The microbiota involved in cocoa pulp fermentations is complex and variable, which leads to inconsistent production efficiency and cocoa quality. Despite intensive research in the field, a detailed and comprehensive analysis of the microbiota is still lacking, especially for the expanding Asian production region. Here, we report a large-scale, comprehensive analysis of four spontaneous Malaysian cocoa pulp fermentations across two time points in the harvest season and two fermentation methods. Our results show that the cocoa microbiota consists of a "core" and a "variable" part. The bacterial populations show a remarkable consistency, with only two dominant species, Lactobacillus fermentum and Acetobacter pasteurianus. The fungal diversity is much larger, with four dominant species occurring in all fermentations ("core" yeasts, and a large number of yeasts that only occur in lower numbers and specific fermentations ("variable" yeasts. Despite this diversity, a clear pattern emerges, with early dominance of apiculate yeasts and late dominance of Saccharomyces cerevisiae. Our results provide new insights into the microbial diversity in Malaysian cocoa pulp fermentations and pave the way for the selection of starter cultures to increase efficiency and consistency.

  15. Mapping the Centimeter-Scale Spatial Variability of PAHs and Microbial Populations in the Rhizosphere of Two Plants.

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    Amélia Bourceret

    Full Text Available Rhizoremediation uses root development and exudation to favor microbial activity. Thus it can enhance polycyclic aromatic hydrocarbon (PAH biodegradation in contaminated soils. Spatial heterogeneity of rhizosphere processes, mainly linked to the root development stage and to the plant species, could explain the contrasted rhizoremediation efficiency levels reported in the literature. Aim of the present study was to test if spatial variability in the whole plant rhizosphere, explored at the centimetre-scale, would influence the abundance of microorganisms (bacteria and fungi, and the abundance and activity of PAH-degrading bacteria, leading to spatial variability in PAH concentrations. Two contrasted rhizospheres were compared after 37 days of alfalfa or ryegrass growth in independent rhizotron devices. Almost all spiked PAHs were degraded, and the density of the PAH-degrading bacterial populations increased in both rhizospheres during the incubation period. Mapping of multiparametric data through geostatistical estimation (kriging revealed that although root biomass was spatially structured, PAH distribution was not. However a greater variability of the PAH content was observed in the rhizosphere of alfalfa. Yet, in the ryegrass-planted rhizotron, the Gram-positive PAH-degraders followed a reverse depth gradient to root biomass, but were positively correlated to the soil pH and carbohydrate concentrations. The two rhizospheres structured the microbial community differently: a fungus-to-bacterium depth gradient similar to the root biomass gradient only formed in the alfalfa rhizotron.

  16. Detailed analysis of the microbial population in Malaysian spontaneous cocoa pulp fermentations reveals a core and variable microbiota.

    Science.gov (United States)

    Meersman, Esther; Steensels, Jan; Mathawan, Melissa; Wittocx, Pieter-Jan; Saels, Veerle; Struyf, Nore; Bernaert, Herwig; Vrancken, Gino; Verstrepen, Kevin J

    2013-01-01

    The fermentation of cocoa pulp is one of the few remaining large-scale spontaneous microbial processes in today's food industry. The microbiota involved in cocoa pulp fermentations is complex and variable, which leads to inconsistent production efficiency and cocoa quality. Despite intensive research in the field, a detailed and comprehensive analysis of the microbiota is still lacking, especially for the expanding Asian production region. Here, we report a large-scale, comprehensive analysis of four spontaneous Malaysian cocoa pulp fermentations across two time points in the harvest season and two fermentation methods. Our results show that the cocoa microbiota consists of a "core" and a "variable" part. The bacterial populations show a remarkable consistency, with only two dominant species, Lactobacillus fermentum and Acetobacter pasteurianus. The fungal diversity is much larger, with four dominant species occurring in all fermentations ("core" yeasts), and a large number of yeasts that only occur in lower numbers and specific fermentations ("variable" yeasts). Despite this diversity, a clear pattern emerges, with early dominance of apiculate yeasts and late dominance of Saccharomyces cerevisiae. Our results provide new insights into the microbial diversity in Malaysian cocoa pulp fermentations and pave the way for the selection of starter cultures to increase efficiency and consistency.

  17. Population variability of phthalate metabolites and bisphenol A concentrations in spot urine samples versus 24- or 48-h collections.

    Science.gov (United States)

    Christensen, Krista L Yorita; Lorber, Matthew; Koch, Holger M; Kolossa-Gehring, Marike; Morgan, Marsha K

    2012-11-01

    Human exposure to phthalates and bisphenol A (BPA) can be assessed through urinary biomonitoring, but methods to infer daily intakes assume that spot sample concentrations are comparable to daily average concentrations. We evaluate this assumption using human biomonitoring data from Germany and the United States (US). The German data comprised three regional studies with spot samples and one with full-day samples analyzed for phthalate metabolites. The US data included: a study on DEHP metabolites and BPA involving eight persons supplying all urine voids (from which 24-h samples were constructed) for seven consecutive days; NHANES spot sample data on DEHP metabolites and BPA; and a regional study of children with 48-h samples analyzed for BPA. In the German data, measures of central tendency differed, but spot and 24-h samples showed generally comparable variance including 95th percentiles and maxima equidistant from central tendency measures. In contrast, the US adult data from the eight-person study showed similar central tendencies for phthalate metabolites and BPA, but generally greater variability for the spot samples, including higher 95th percentiles and maxima. When comparing children's BPA concentrations in NHANES spot and 48-h samples, distributions showed similar central tendency and variability. Overall, spot urinary concentrations of DEHP metabolites and BPA have variability roughly comparable with corresponding 24-h average concentrations obtained from a comparable population, suggesting that spot samples can be used to characterize population distributions of intakes. However, the analysis also suggests that caution should be exercised when interpreting the high end of spot sample data sets.

  18. Demographic variables, clinical aspects, and medicolegal implications in a population of patients with adjustment disorder

    Directory of Open Access Journals (Sweden)

    Anastasia A

    2016-04-01

    Full Text Available Annalisa Anastasia,1 Chiara Colletti,1 Valentina Cuoco,1 Adele Quartini,1 Stefania Urso,2 Raffaella Rinaldi,2 Giuseppe Bersani1 1Department of Medical-Surgical Sciences and Biotechnologies, Faculty of Pharmacy and Medicine, Sapienza University of Rome, 2Department of Anatomical, Istological, Forensic and Locomotor System Sciences, Sapienza University of Rome, Rome, Italy Introduction: Although adjustment disorder (AD is considered as residual diagnosis and receives little attention in research, it plays an important role in clinical practice and also assumes an increasingly important role in the field of legal medicine, where the majority of diagnostic frameworks (eg, mobbing often refer to AD. Our study aimed to look for specific stressor differences among demographic and clinical variables in a naturalistic setting of patients with AD.Methods: A restrospective statistical analysis of the data of patients diagnosed with AD from November 2009 to September 2012, identified via manual search from the archive of the outpatient setting at the University Unit of Psychiatry “A. Fiorini” Hospital, Terracina (Latina, Italy, was performed.Results: The sample consisted of 93 patients (46 males and 47 females, aged between 26 and 85, with medium–high educational level who were mainly employed. In most cases (54.80%, a diagnosis of AD with mixed anxiety and depressed mood was made. In all, 72% of the sample reported a negative family history for psychiatric disorders. In 22.60%, a previous history of psychopathology, especially mood disorders (76.19%, was reported. The main stressors linked to the development of AD were represented by working problems (32.30%, family problems (23.70%, and/or somatic disease (22.60% with significant differences with respect to age and sex. Half of the patients were subjected to a single first examination; 24.47% requested a copy of medical records.Conclusion: Confirming previous data from previous reports, our results

  19. Effect of variable consumption habits in the Nordic populations on ECOSYS model predictions of ingestion dose

    International Nuclear Information System (INIS)

    Nielsen, Sven P.; Andersson, Kasper G.; Hansen, Hanne S.; Thoerring, Haavard; Joensen, Hans P.; Isaksson, Mats; Kostiainen, Eila; Suolanen, Vesa; Sigurgeirsson, Magnus A.; Palsson, Sigurour E.

    2008-01-01

    the northernmost areas used for grain crops, the crops are entirely spring grain crops, whereas in Denmark and Germany, winter crops are dominant. This gives large deviations in growth periods and development stages of the crops, particularly in the spring. This implies that first year doses from the same contaminant plume can be very different in different Nordic countries. Thus we conclude that the food habits of the population in the Nordic countries affected the calculated ingestion dose significantly. Also it is important to ascertain the use of state-of-the-art data for the more generic model parameters and to test the effect of other parameters to improve the decision support system used in the Nordic countries. (author)

  20. Variable effects of cinder-cone eruptions on prehistoric agrarian human populations in the American southwest

    Science.gov (United States)

    Ort, Michael H.; Elson, Mark D.; Anderson, Kirk C.; Duffield, Wendell A.; Samples, Terry L.

    2008-10-01

    Two ˜ 900 BP cinder-cone eruptions in the American Southwest affected prehistoric human populations in different ways, mostly because of differences in the eruption styles and area affected. Primary pre-eruption cultural factors that may have led to successful adaptation to the eruptions include decision-making at the family or household level, low investment in site structures, dispersion of agricultural sites in varied environments, and settlement spread over a large area so that those who were less affected could shelter and feed evacuees. Sunset Crater, near Flagstaff, Arizona, produced about 8 km 2 lava flow fields and a ˜ 2300-km 2 tephra blanket in an area that had been settled by prehistoric groups for at least 1000 years. Local subsistence relied on agriculture, primarily maize, and > 30 cm tephra cover rendered 265 km 2 of prime land unfarmable. This area was apparently abandoned for at least several generations. A > 500-km 2 area was probably marked by collapsed roofs and other structural damage from the fallout. If the eruption occurred during the agricultural season, the fallout would also have significantly damaged crops. The eruption did have some benefits to local groups because lower elevation land, which had previously been too dry to farm, became agriculturally productive due to 3-8 cm of tephra 'mulch' and some temporary soil nutrient improvements. This previously uninhabited land became the site of significant year-round settlement and farming, eventually containing some of the largest pueblo structures ever built in the region. New agricultural techniques were developed to manage the fallout mulch. The eruption also affected ceramic production and trading patterns, and volcano-related ritual behavior - the production of maize-impressed lava-spatter agglutinate - was initiated. Little Springs Volcano, about 200 km northwest of Sunset Crater, is a small spatter rampart around a series of vents that produced about 5 km 2 of lava flow fields

  1. False memories with age: neural and cognitive underpinnings

    Science.gov (United States)

    Devitt, Aleea L.; Schacter, Daniel L.

    2016-01-01

    As we age we become increasingly susceptible to memory distortions and inaccuracies. Over the past decade numerous neuroimaging studies have attempted to illuminate the neural underpinnings of aging and false memory. Here we review these studies, and link their findings with those concerning the cognitive properties of age-related changes in memory accuracy. Collectively this evidence points towards a prominent role for age-related declines in medial temporal and prefrontal brain areas, and corresponding impairments in associative binding and strategic monitoring. A resulting cascade of cognitive changes contributes to the heightened vulnerability to false memories with age, including reduced recollective ability, a reliance on gist information and familiarity-based monitoring mechanisms, as well as a reduced ability to inhibit irrelevant information and erroneous binding of features between memory traces. We consider both theoretical and applied implications of research on aging and false memories, as well as questions remaining to be addressed in future research. PMID:27592332

  2. Analysis of the populations genetic variability of Tagosodes orizicolus (Homoptera: Delphacidae), virus vector of the rice white leaf

    International Nuclear Information System (INIS)

    Hernandez Alfaro, Myriam

    2006-01-01

    Tagosodes orizicolus (Homoptera: Delphacidae), is a monophagous insect of the rice and virus vector of the white leaf (RHBV). It is distributed in America Central, El Caribe, part of the America del Sur and in Costa Rica it is in all the producing zones of rice. The genetic variability was analyzed by means of RAPD-PCR of individuals from three populations of Costa Rica: Parrita, Guanacaste (Liberia) y San Carlos (Santa Clara), that they are found separated geographically. The technique consisted of amplifying regions at random of the genome of these insects utilizing five primers. A total of 72 polymorphic bands were obtained, that upon being analyzed statistically by means of the multivariate analysis program of numerical taxonomy could show a clear genetic distancing among said populations. The genetic distance observed in the molecular analysis can be explained for the climatic and/or geographical isolation of the populations or by the incident of Wolbachia, riquettsia that induces cytoplasmic sterility in insects. These symbionts are transmitted of generation in generation, of the mother to their offspring and they cause reproductive alterations as cytoplasmic incompatibility, parthenogenesis and feminization. The presence of Wolbachia was determined by means of transmission electronic microscopy being observed in the greasy and muscular weave of the abdomen of T. orizicolus. Rickettsias present pleomorphic morphology and form small groups, that are characterized for the presence of electrondense material semidetached to the cell wall with an interior electronlucent. Its size in transverse cuts ranged between 520 nm of length X 470 nm of width. In addition, its presence was detected by means of the amplification by PCR of the genomic DNA of the insects; a specific primer for the DNA ribosomal 16S of Wolbachia was utilized for it. A 86% of insects of the San Carlos population were positive, a 96% was determined for Guanacaste, a 37% for Parrita and a 100% for

  3. Variability in body mass and sexual dimorphism in Danish red foxes (Vulpes vulpes) in relation to population density

    DEFF Research Database (Denmark)

    Pagh, Sussie; Hansen, Mette Sif; Jensen, Birger

    2018-01-01

    For the first time, temporal variability in body size and sexual dimorphism is revealed in foxes Vulpes vulpes from the same geographical area at over time. The weights and lengths of 552 Danish foxes were documented during three different periods: 1965–1977, 2012–2014 and the winter of 2015...... of 2012–2014, no difference in body fat measured by rump fat thickness (RFT) was found between age groups and genders in contrast to 2015/2016, when RFT was significantly (p ...–1977 and compared to 2015/2016, compared to 2012–2014, when population density was high (the mean weight: 6.8 kg). However, no significant differences were found in the weight of females. Hence, sexual dimorphism ranged from 7.6 to 3.6 in adult foxes in low and high-density periods, respectively. During the winters...

  4. Conventional clinical and prognostic variables in 150 oral squamous cell carcinoma cases from the indigenous population of Karachi.

    Science.gov (United States)

    Alamgir, Muhammad Mohiuddin; Jamal, Qamar; Mirza, Talat

    2016-01-01

    To analyze clinical and prognostic variables of Oral Squamous Cell Carcinoma (OSCC) cases from the indigenous population of Karachi and to correlate with the common risk factor of tobacco habit. The study was conducted at Ziauddin University, Karachi. One hundred fifty OSCC cases were collected from the Oncology Department of Ziauddin University Hospital, North Nazimabad, Karachi and Otolaryngology ward of Civil Hospital, Karachi, during 2011 and 2015. The reporting included demographic details and variables like intra-oral subsites, clinical stage and histological grade. Recurrence of tumor after initial resection was also documented. The patient's population comprised of 98 males and 52 females. The mean age was 47.1± 12.22 (range:20-78 years). Maximum numbers were seen in the 41-50 years age group. Urdu-speaking community was the most affected ethnic group (n=75). Clinico-pathological analysis revealed that majority of cases were moderately differentiated (59%) and were either clinical stage II (35%) or IV (29%) tumors. The most common intra-oral subsite came out to be buccal mucosa of cheeks (56%) followed by lateral borders of tongue (21%), lips (13%), alveolar (6%), palate (2.6%) floor of mouth (1.3%), etc. Recurrence was observed in 08 out of 150 cases. All patients underwent primary resection±neck dissection and reconstruction where possible. Overall experience with oral squamous cell carcinoma shows that it has a high tendency for local invasion as well as dissemination to regional lymph nodes, i.e. cervical lymph nodes, both are associated with a poor prognosis. Preventable risk factor of tobacco chewing has been observed in majority of these cases.

  5. Population variables and life-history characteristics of the alligator pipefish Syngnathoides biaculeatus, in Papua New Guinea.

    Science.gov (United States)

    Barrows, A P W; Martin-Smith, K M; Baine, M S P

    2009-03-01

    Population structure and life-history variables of the widely distributed alligator pipefish Syngnathoides biaculeatus were characterized in Bootless Bay, Papua New Guinea over the course of 11 months. There was little evidence of seasonality with four focal populations showing no significant change in abundance. Similarly, the sex ratio remained 1:1 for all but 1 month. Reproductive males carrying eggs (148-278 mm in total length, L(T)) were found in all months. Brood size was significantly, positively related to male L(T) for newly laid broods only. Maximum observed brood size was 351 and mean +/-s.d. brood size was 238 +/- 57 for newly laid broods. Juveniles and males showed no change in mean L(T) over the year while slightly smaller females were captured in November 2006 and September 2007. Males were significantly longer than females so von Bertalanffy growth coefficients were estimated separately for each sex: males L(infinity)= 285 mm, K = 0.82 year(-1) and females L(infinity)= 261 mm, K = 1.10 year(-1). These estimates suggest that this species grows rapidly and has a short-life span. In the context of growing concern about overexploitation of syngnathids, a rapid growth rate combined with year round reproductive activity suggests that the tropical S. biaculeatus may be relatively resilient with regard to fishing pressure.

  6. Population variability in biological adaptive responses to DNA damage and the shapes of carcinogen dose-response curves

    International Nuclear Information System (INIS)

    Conolly, Rory B.; Gaylor, David W.; Lutz, Werner K.

    2005-01-01

    Carcinogen dose-response curves for both ionizing radiation and chemicals are typically assumed to be linear at environmentally relevant doses. This assumption is used to ensure protection of the public health in the absence of relevant dose-response data. A theoretical justification for the assumption has been provided by the argument that low dose linearity is expected when an exogenous agent adds to an ongoing endogenous process. Here, we use computational modeling to evaluate (1) how two biological adaptive processes, induction of DNA repair and cell cycle checkpoint control, may affect the shapes of dose-response curves for DNA-damaging carcinogens and (2) how the resulting dose-response behaviors may vary within a population. Each model incorporating an adaptive process was capable of generating not only monotonic dose-responses but also nonmonotonic (J-shaped) and threshold responses. Monte Carlo analysis suggested that all these dose-response behaviors could coexist within a population, as the spectrum of qualitative differences arose from quantitative changes in parameter values. While this analysis is largely theoretical, it suggests that (a) accurate prediction of the qualitative form of the dose-response requires a quantitative understanding of the mechanism (b) significant uncertainty is associated with human health risk prediction in the absence of such quantitative understanding and (c) a stronger experimental and regulatory focus on biological mechanisms and interindividual variability would allow flexibility in regulatory treatment of environmental carcinogens without compromising human health

  7. Variability and population genetic structure in Achyrocline flaccida (Weinm. DC., a species with high value in folk medicine in South America.

    Directory of Open Access Journals (Sweden)

    Juliana da Rosa

    Full Text Available Better knowledge of medicinal plant species and their conservation is an urgent need worldwide. Decision making for conservation strategies can be based on the knowledge of the variability and population genetic structure of the species and on the events that may influence these genetic parameters. Achyrocline flaccida (Weinm. DC. is a native plant from the grassy fields of South America with high value in folk medicine. In spite of its importance, no genetic and conservation studies are available for the species. In this work, microsatellite and ISSR (inter-simple sequence repeat markers were used to estimate the genetic variability and structure of seven populations of A. flaccida from southern Brazil. The microsatellite markers were inefficient in A. flaccida owing to a high number of null alleles. After the evaluation of 42 ISSR primers on one population, 10 were selected for further analysis of seven A. flaccida populations. The results of ISSR showed that the high number of exclusive absence of loci might contribute to the inter-population differentiation. Genetic variability of the species was high (Nei's diversity of 0.23 and Shannon diversity of 0.37. AMOVA indicated higher genetic variability within (64.7% than among (33.96% populations, and the variability was unevenly distributed (FST 0.33. Gene flow among populations ranged from 1.68 to 5.2 migrants per generation, with an average of 1.39. The results of PCoA and Bayesian analyses corroborated and indicated that the populations are structured. The observed genetic variability and population structure of A. flaccida are discussed in the context of the vegetation formation history in southern Brazil, as well as the possible anthropogenic effects. Additionally, we discuss the implications of the results in the conservation of the species.

  8. IN SITU COMPARISON OF TREE-RING RESPONSES TO CLIMATE AND POPULATION GENETICS: THE NEED TO CONTROL FOR LOCAL CLIMATE AND SITE VARIABLES

    Directory of Open Access Journals (Sweden)

    Johann Mathias Housset

    2016-10-01

    Full Text Available Tree species responses to climate change will be greatly influenced by their evolutionary potential and their phenotypic plasticity. Investigating tree-rings responses to climate and population genetics at the regional scale is therefore crucial in assessing the tree behaviour to climate change. This study combined in situ dendroclimatology and population genetics over a latitudinal gradient and compared the variations between the two at the intra- and inter-population levels. This approach was applied on the northern marginal populations of Thuja occidentalis (eastern white-cedar in the Canadian boreal forest. We aimed first to assess the radial growth variability (response functional trait within populations across the gradient and to compare it with the genetic diversity (microsatellites. Second, we investigated the variability in the growth response to climate at the regional scale through the radial growth-climate relationships, and tested its correlation with environmental variables and population genetic structure. Model selection based on the Akaike Information Criteria revealed that the growth synchronicity between pairs of trees of a population covariates with both the genetic diversity of this population and the amount of precipitation (inverse correlation, although these variables only explained a small fraction of the observed variance. At the regional scale, variance partitioning and partial redundancy analysis indicate that the growth response to climate was greatly modulated by stand environmental variables, suggesting predominant plastic variations in growth-response to climate. Combining in situ dendroclimatology and population genetics is a promising way to investigate species’ response capacity to climate change in natural stands. We stress the need to control for local climate and site conditions effects on dendroclimatic response to climate to avoid misleading conclusions regarding the associations with genetic variables.

  9. Variability in the germination of spores among and within natural populations of the endangered tree fern Dicksonia sellowiana Hook. (Xaxim

    Directory of Open Access Journals (Sweden)

    Gabriela Schmitz Gomes

    2006-01-01

    Full Text Available The objective of this study was to analyze the existing variability in the germination of individuals' spores collected from two natural populations of Dicksonia sellowiana in southern Brazil. The largest intrapopulational variation was observed for the spores germination. These results suggested the existence of adaptative strategies that favored the gradual and continuous entrance of new individuals into the gametophytic population. The behavior of the individuals of the species within each population followed a similar pattern of initial development, in spite of conspicuous differences in the population structure. This showed a low differentiation between the populations and the existence of adaptative strategies which were common to both communities.O Xaxim (Dicksonia sellowiana Hook. (Dicksoniaceae é uma samambaia arborescente que se encontra principalmente sob o domínio da Floresta Ombrófila Mista. A exploração intensiva de seus indivíduos para retirada do caule, empregado na fabricação de vasos e substrato para o cultivo de plantas ornamentais, e a crescente antropização das áreas florestadas, tem degradado suas populações naturais. Este estudo teve como objetivo analisar a variabilidade existente na germinação de esporos de Xaxim. Os esporos foram coletados das frondes de indivíduos de Xaxim procedentes de duas populações naturais do Sul do Brasil. Foi observada uma maior variação intrapopulacional para a germinação e porcentagem de esporos inviáveis. Estes resultados sugerem a existência de estratégias adaptativas que favorecem a entrada gradual e contínua de novos indivíduos na população de gametófitos. O comportamento dos indivíduos da espécie dentro de cada população segue padrão semelhante de velocidade de desenvolvimento inicial, a despeito das diferenças conspícuas na estrutura populacional, sugerindo baixa diferenciação entre as populações e a existência de estratégias adaptativas comuns

  10. Dealing with incomplete and variable detectability in multi-year, multi-site monitoring of ecological populations

    Science.gov (United States)

    Converse, Sarah J.; Royle, J. Andrew; Gitzen, Robert A.; Millspaugh, Joshua J.; Cooper, Andrew B.; Licht, Daniel S.

    2012-01-01

    An ecological monitoring program should be viewed as a component of a larger framework designed to advance science and/or management, rather than as a stand-alone activity. Monitoring targets (the ecological variables of interest; e.g. abundance or occurrence of a species) should be set based on the needs of that framework (Nichols and Williams 2006; e.g. Chapters 2–4). Once such monitoring targets are set, the subsequent step in monitoring design involves consideration of the field and analytical methods that will be used to measure monitoring targets with adequate accuracy and precision. Long-term monitoring programs will involve replication of measurements over time, and possibly over space; that is, one location or each of multiple locations will be monitored multiple times, producing a collection of site visits (replicates). Clearly this replication is important for addressing spatial and temporal variability in the ecological resources of interest (Chapters 7–10), but it is worth considering how this replication can further be exploited to increase the effectiveness of monitoring. In particular, defensible monitoring of the majority of animal, and to a lesser degree plant, populations and communities will generally require investigators to account for imperfect detection (Chapters 4, 18). Raw indices of population state variables, such as abundance or occupancy (sensu MacKenzie et al. 2002), are rarely defensible when detection probabilities are failing to correct for differences in detection, resulting in indices that have an unknown relationship to the parameters of interest (e.g. Nichols 1992, Anderson 2001, MacKenzie et al. 2002, Williams et al. 2002, Anderson 2003, White 2005, Kéry and Schmidt 2008). While others have argued that indices may be preferable in some cases due to the challenges associated with estimating detection probabilities (e.g. McKelvey and Pearson 2001, Johnson 2008), we do not attempt to resolve this debate here. Rather, we are

  11. Dealing with incomplete and variable detectability in multi-year, multi-site monitoring of ecological populations

    Science.gov (United States)

    Converse, Sarah J.; Royle, J. Andrew; Gitzen, Robert A.; Millspaugh, Joshua J.; Cooper, Andrew B.; Licht, Daniel S.

    2012-01-01

    An ecological monitoring program should be viewed as a component of a larger framework designed to advance science and/or management, rather than as a stand-alone activity. Monitoring targets (the ecological variables of interest; e.g. abundance or occurrence of a species) should be set based on the needs of that framework (Nichols and Williams 2006; e.g. Chapters 2–4). Once such monitoring targets are set, the subsequent step in monitoring design involves consideration of the field and analytical methods that will be used to measure monitoring targets with adequate accuracy and precision. Long-term monitoring programs will involve replication of measurements over time, and possibly over space; that is, one location or each of multiple locations will be monitored multiple times, producing a collection of site visits (replicates). Clearly this replication is important for addressing spatial and temporal variability in the ecological resources of interest (Chapters 7–10), but it is worth considering how this replication can further be exploited to increase the effectiveness of monitoring. In particular, defensible monitoring of the majority of animal, and to a lesser degree plant, populations and communities will generally require investigators to account for imperfect detection (Chapters 4, 18). Raw indices of population state variables, such as abundance or occupancy (sensu MacKenzie et al. 2002), are rarely defensible when detection probabilities are challenges associated with estimating detection probabilities (e.g. McKelvey and Pearson 2001, Johnson 2008), we do not attempt to resolve this debate here. Rather, we are more apt to agree with MacKenzie and Kendall (2002) that the burden of proof ought to be on the assertion that detection probabilities are constant. Furthermore, given the wide variety of field methods available for estimating detection probabilities and the inability for an investigator to know, a priori, if detection probabilities will be

  12. [Patterns of morphological variability in reintroduced populations with two beaver subspecies Castor fiber orientoeuropaeus and Castor fiber belorussicus (Castoridae, Rodentia) as an example].

    Science.gov (United States)

    Korablev, N P; Korablev, P N

    2012-01-01

    Taking as an example two beaver subspecies (Castor fiber orientoeuropaeus and Castor fiber belorussicus) with documented history of population formation, the patterns of morphological variability in translocated groups of mammals are studied. The variability of quantitative and qualitative traits in the formed populations is not characterized by a single direction. The main trend consists in increasing of adaptive norms diversity as related to body size. There observed a slight increase in the level of fluctuating asymmetry, reduction in polymorphism of nonmetric traits, and increase in fraction of rare aberrations. All these may be caused by inbreeding taking place during the period of prapopulations formation. The results of the study allow for considering the intraspecific differentiation as a consequence of adaptive variability (adaptatiogenesis) or subspecies hybridization. As for stochastic processes (genetic drift, founder effect), they seem to not influence the morphological variability significantly. The differences between discrete and dimensional traits are indicative of population groups' peculiarity.

  13. Day-to-Day Blood Pressure Variability and Risk of Dementia in a General Japanese Elderly Population: The Hisayama Study.

    Science.gov (United States)

    Oishi, Emi; Ohara, Tomoyuki; Sakata, Satoko; Fukuhara, Masayo; Hata, Jun; Yoshida, Daigo; Shibata, Mao; Ohtsubo, Toshio; Kitazono, Takanari; Kiyohara, Yutaka; Ninomiya, Toshiharu

    2017-08-08

    Several observational studies have reported that higher visit-to-visit blood pressure variability is a risk factor for cognitive impairment and dementia. However, no studies have investigated the association of day-to-day blood pressure variability assessed by home blood pressure measurement with the development of dementia. A total of 1674 community-dwelling Japanese elderly without dementia, ≥60 years of age, were followed up for 5 years (2007-2012). Home blood pressure was measured 3 times every morning for a median of 28 days. Day-to-day systolic (SBP) and diastolic blood pressure variabilities, calculated as coefficients of variation (CoV) of home SBP and diastolic blood pressure, were categorized into quartiles. The hazard ratios and their 95% confidence intervals of the CoV levels of home blood pressure on the development of all-cause dementia, vascular dementia (VaD), and Alzheimer disease (AD) were computed with a Cox proportional hazards model. During the follow-up, 194 subjects developed all-cause dementia; of these, 47 had VaD and 134 had AD. The age- and sex-adjusted incidences of all-cause dementia, VaD, and AD increased significantly with increasing CoV levels of home SBP (all P for trend dementia, VaD, and AD were significantly higher in those in the fourth quartile (hazard ratio=2.27, 95% confidence interval=1.45-3.55, P dementia; hazard ratio=2.79, 95% confidence interval=1.04-7.51, P =0.03 for VaD; hazard ratio=2.22, 95% confidence interval=1.31-3.75, P dementia and AD. There was no interaction between home SBP levels and CoV levels of home SBP on the risk of each subtype of dementia. Our findings suggest that increased day-to-day blood pressure variability is, independently of average home blood pressure, a significant risk factor for the development of all-cause dementia, VaD, and AD in the general elderly Japanese population. © 2017 The Authors.

  14. The digital national framework - underpinning the knowledge economy

    Directory of Open Access Journals (Sweden)

    K J Murray

    2003-10-01

    Full Text Available Providing a sustainable spatial data infrastructure creates responsibility and high demand by continually meeting and satisfying the needs of all kinds of users. It is essential to provide the right information at the right level of quality and reliability and at the right time. Geographic information (GI is today being universally recognised as a key part of the national information infrastructure, especially by government. GI is an enabler in the knowledge economy since the power of geography can be used to underpin the sharing (and trading of vital georeferenced information collected by all kinds of organisations. From this information reliable conclusions can and will be drawn and decisions made. However, achieving such an environment does not just happen. It has to be led, nurtured and developed in line with user needs. Funding requires sustained investment, and it all has to be implemented and maintained whether the economy enjoys good times or bad, and through periods of political change. These are all big challenges encountered by just about every national economy. The aim of many national governments around the world is to establish a reliable and integrated reference base for GI that can underpin the e-economy. This base needs to support government and the commercial sector who need to reference information, and potentially share it with others (eg land ownership or link it up to form an application.(eg location based services. To achieve this a consistent method of georefererencing is required and the Digital National Framework is intended to fulfil that need in Great Britain. This paper will describe what has been happening in Great Britain to build on the firm foundations of the past, and develop a modern and sustainable framework for geographic information for the future. In particular it will be shown that the business model adopted by Ordnance Survey in recent years (ie the users pay for the data has played a key role in securing

  15. False memories with age: Neural and cognitive underpinnings.

    Science.gov (United States)

    Devitt, Aleea L; Schacter, Daniel L

    2016-10-01

    As we age we become increasingly susceptible to memory distortions and inaccuracies. Over the past decade numerous neuroimaging studies have attempted to illuminate the neural underpinnings of aging and false memory. Here we review these studies, and link their findings with those concerning the cognitive properties of age-related changes in memory accuracy. Collectively this evidence points towards a prominent role for age-related declines in medial temporal and prefrontal brain areas, and corresponding impairments in associative binding and strategic monitoring. A resulting cascade of cognitive changes contributes to the heightened vulnerability to false memories with age, including reduced recollective ability, a reliance on gist information and familiarity-based monitoring mechanisms, as well as a reduced ability to inhibit irrelevant information and erroneous binding of features between memory traces. We consider both theoretical and applied implications of research on aging and false memories, as well as questions remaining to be addressed in future research. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. The educational theory underpinning a clinical workbook for VERT

    Energy Technology Data Exchange (ETDEWEB)

    Nisbet, Heather, E-mail: heather.nisbet@orh.nhs.u [Department of Clinical Oncology, Churchill Hospital, Old Road, Headington, Oxford, Oxon OX3 7LJ (United Kingdom); Matthews, Sara [Department of Clinical Oncology, Churchill Hospital, Old Road, Headington, Oxford, Oxon OX3 7LJ (United Kingdom)

    2011-02-15

    The introduction of VERT (Virtual Environment for Radiotherapy Training) into radiotherapy departments across England was in response to the National Radiotherapy Advisory Group's (NRAG) recommendation to the Department of Health that it may assist in enhancing the clinical learning experience of student radiotherapy radiographers. It was suggested that this may help to reduce the high attrition rate of students currently experienced, particularly in the first year of training. This paper investigates how VERT may be used in the clinical setting to develop the skills of students, in order to meet this vision. We argue that using an epistemological approach, i.e. using the theory of knowledge, to support the design of the learning resource, is key to enabling the educator to fulfil these expectations. We describe the design of a generic VERT workbook for use in the clinical departments that train students for the University of Hertfordshire. The use of educational theory to underpin the aims and inform the development of the workbook is examined. We then discuss the alignment of the workbook with the curriculum in order to enhance the students' learning experience and nurture their clinical competence. Finally, we will consider the teaching strategies used during the delivered sessions and discuss how we believe they will allow us to achieve these aims.

  17. The educational theory underpinning a clinical workbook for VERT

    International Nuclear Information System (INIS)

    Nisbet, Heather; Matthews, Sara

    2011-01-01

    The introduction of VERT (Virtual Environment for Radiotherapy Training) into radiotherapy departments across England was in response to the National Radiotherapy Advisory Group's (NRAG) recommendation to the Department of Health that it may assist in enhancing the clinical learning experience of student radiotherapy radiographers. It was suggested that this may help to reduce the high attrition rate of students currently experienced, particularly in the first year of training. This paper investigates how VERT may be used in the clinical setting to develop the skills of students, in order to meet this vision. We argue that using an epistemological approach, i.e. using the theory of knowledge, to support the design of the learning resource, is key to enabling the educator to fulfil these expectations. We describe the design of a generic VERT workbook for use in the clinical departments that train students for the University of Hertfordshire. The use of educational theory to underpin the aims and inform the development of the workbook is examined. We then discuss the alignment of the workbook with the curriculum in order to enhance the students' learning experience and nurture their clinical competence. Finally, we will consider the teaching strategies used during the delivered sessions and discuss how we believe they will allow us to achieve these aims.

  18. Emerging Technological Risk Underpinning the Risk of Technology Innovation

    CERN Document Server

    Anderson, Stuart

    2012-01-01

    Classes of socio-technical hazards allow a characterization of the risk in technology innovation and clarify the mechanisms underpinning emergent technological risk. Emerging Technological Risk provides an interdisciplinary account of risk in socio-technical systems including hazards which highlight: ·         How technological risk crosses organizational boundaries, ·         How technological trajectories and evolution develop from resolving tensions emerging between social aspects of organisations and technologies and ·         How social behaviour shapes, and is shaped by, technology. Addressing an audience from a range of academic and professional backgrounds, Emerging Technological Risk is a key source for those who wish to benefit from a detail and methodical exposure to multiple perspectives on technological risk. By providing a synthesis of recent work on risk that captures the complex mechanisms that characterize the emergence of risk in technology innovation, Emerging Tec...

  19. Renewable energy technology from underpinning physics to engineering application

    International Nuclear Information System (INIS)

    Infield, D G

    2008-01-01

    The UK Energy Research Centre (UKERC) in it's submission to the DTI's 2006 Energy Review reminded us that the 'UK has abundant wind, wave and tidal resources available; its mild climate lends itself to bio-energy production, and solar radiation levels are sufficient to sustain a viable solar industry'. These technologies are at different stages of development but they all draw on basic and applied Science and Engineering. The paper will briefly review the renewable energy technologies and their potential for contributing to a sustainable energy supply. Three research topics will be highlighted that bridge the gap between the physics underpinning the energy conversion, and the engineering aspects of development and deployment; all three are highly relevant to the Government's programme on micro-generation. Two are these are taken from field of thin film photovoltaics (PV), one related to novel device development and the other to a measurement technique for assessing the manufacturing quality of PV modules and their performance. The third topic concerns the development of small building integrated wind turbines and examines the complex flow associated with such applications. The paper will conclude by listing key research challenges that are central to the search for efficient and cost-effective renewable energy generation

  20. Studying variability in human brain aging in a population-based German cohort – Rationale and design of 1000BRAINS

    Directory of Open Access Journals (Sweden)

    Svenja eCaspers

    2014-07-01

    Full Text Available The ongoing 1000 brains study (1000BRAINS is an epidemiological and neuroscientific investigation of structural and functional variability in the human brain during aging. The two recruitment sources are the 10-year follow-up cohort of the German Heinz Nixdorf Recall (HNR Study, and the HNR MultiGeneration Study cohort, which comprises spouses and offspring of HNR subjects. The HNR is a longitudinal epidemiological investigation of cardiovascular risk factors, with a comprehensive collection of clinical, laboratory, socioeconomic, and environmental data from population-based subjects aged 45-75 years on inclusion. HNR subjects underwent detailed assessments in 2000, 2006, and 2011, and completed annual postal questionnaires on health status. 1000BRAINS accesses these HNR data and applies a separate protocol comprising: neuropsychological tests of attention, memory, executive functions & language; examination of motor skills; ratings of personality, life quality, mood & daily activities; analysis of laboratory and genetic data; and state-of-the-art magnetic resonance imaging (MRI, 3 Tesla of the brain. The latter includes (i 3D-T1- and 3D-T2-weighted scans for structural analyses and myelin mapping; (ii three diffusion imaging sequences optimized for diffusion tensor imaging, high-angular resolution diffusion imaging for detailed fibre tracking and for diffusion kurtosis imaging; (iii resting-state and task-based functional MRI; and (iv fluid-attenuated inversion recovery and MR angiography for the detection of vascular lesions and the mapping of white matter lesions. The unique design of 1000BRAINS allows: (i comprehensive investigation of various influences including genetics, environment and health status on variability in brain structure and function during aging; and (ii identification of the impact of selected influencing factors on specific cognitive subsystems and their anatomical correlates.

  1. Genetic variability of wild populations of Leporinus elongatus in the São Domingos River - MS Brazil: a preliminary view on the construction of the hydroelectric plant

    Directory of Open Access Journals (Sweden)

    Ricardo Pereira Ribeiro

    2016-09-01

    Full Text Available Most of the electricity used in Brazil comes from hydroelectric plants, mainly due to the great availability of its water resources. However, the construction of these plants denotes serious problems related to migration of native fish and the genetic conservation of stocks. Current study evaluates two wild population of Leporinus elongatus (piapara located downstream (Population A - PopA and upstream (Population B - PopB of the Cachoeira Branca before the construction of the São Domingos hydroelectric plant (HPP in the Mato Grosso do Sul State, Brazil. Thirty samples from caudal fins were collected and analyzed for each population. Eighty-nine fragments, including 72 polymorphic ones (80.9%, were analyzed. Low fragments (less than 0.100 in both populations (PopA = 2 and PopB = 3 were identified. Nine fixed fragments (frequency 1.000 (PopA = 3 and PopB = 6, and four exclusive fragments (PopA = 3 and PopB = 1 were also reported. The genetic variability within populations, calculated by Shannon Index and by percentage of polymorphic fragments, indicated high rates of intrapopulation variability (PopA = 0.309 and 61.80% and PopB = 0.392 and 71.90%, respectively. Genetic distance and identity rates (0.089 and 0.915, respectively were different between populations, whilst AMOVA showed that most variations lie within the populations and not between them. Fst and Nm rates showed moderate genetic differentiation with low numbers of migrants. Results reveal populations with high intra-population genetic variability and genetic differentiation, with low gene flow. The passage ladders of São Domingos HPP should control fish transposition to preserve genetic variability.

  2. Genetic variability and natural selection at the ligand domain of the Duffy binding protein in brazilian Plasmodium vivax populations

    Directory of Open Access Journals (Sweden)

    Gil Luiz HS

    2010-11-01

    Full Text Available Abstract Background Plasmodium vivax malaria is a major public health challenge in Latin America, Asia and Oceania, with 130-435 million clinical cases per year worldwide. Invasion of host blood cells by P. vivax mainly depends on a type I membrane protein called Duffy binding protein (PvDBP. The erythrocyte-binding motif of PvDBP is a 170 amino-acid stretch located in its cysteine-rich region II (PvDBPII, which is the most variable segment of the protein. Methods To test whether diversifying natural selection has shaped the nucleotide diversity of PvDBPII in Brazilian populations, this region was sequenced in 122 isolates from six different geographic areas. A Bayesian method was applied to test for the action of natural selection under a population genetic model that incorporates recombination. The analysis was integrated with a structural model of PvDBPII, and T- and B-cell epitopes were localized on the 3-D structure. Results The results suggest that: (i recombination plays an important role in determining the haplotype structure of PvDBPII, and (ii PvDBPII appears to contain neutrally evolving codons as well as codons evolving under natural selection. Diversifying selection preferentially acts on sites identified as epitopes, particularly on amino acid residues 417, 419, and 424, which show strong linkage disequilibrium. Conclusions This study shows that some polymorphisms of PvDBPII are present near the erythrocyte-binding domain and might serve to elude antibodies that inhibit cell invasion. Therefore, these polymorphisms should be taken into account when designing vaccines aimed at eliciting antibodies to inhibit erythrocyte invasion.

  3. A critical assessment of the ecological assumptions underpinning compensatory mitigation of salmon-derived nutrients

    Science.gov (United States)

    Collins, Scott F.; Marcarelli, Amy M.; Baxter, Colden V.; Wipfli, Mark S.

    2015-01-01

    We critically evaluate some of the key ecological assumptions underpinning the use of nutrient replacement as a means of recovering salmon populations and a range of other organisms thought to be linked to productive salmon runs. These assumptions include: (1) nutrient mitigation mimics the ecological roles of salmon, (2) mitigation is needed to replace salmon-derived nutrients and stimulate primary and invertebrate production in streams, and (3) food resources in rearing habitats limit populations of salmon and resident fishes. First, we call into question assumption one because an array of evidence points to the multi-faceted role played by spawning salmon, including disturbance via redd-building, nutrient recycling by live fish, and consumption by terrestrial consumers. Second, we show that assumption two may require qualification based upon a more complete understanding of nutrient cycling and productivity in streams. Third, we evaluate the empirical evidence supporting food limitation of fish populations and conclude it has been only weakly tested. On the basis of this assessment, we urge caution in the application of nutrient mitigation as a management tool. Although applications of nutrients and other materials intended to mitigate for lost or diminished runs of Pacific salmon may trigger ecological responses within treated ecosystems, contributions of these activities toward actual mitigation may be limited.

  4. Estimation of expected number of accidents and workforce unavailability through Bayesian population variability analysis and Markov-based model

    International Nuclear Information System (INIS)

    Chagas Moura, Márcio das; Azevedo, Rafael Valença; Droguett, Enrique López; Chaves, Leandro Rego; Lins, Isis Didier

    2016-01-01

    Occupational accidents pose several negative consequences to employees, employers, environment and people surrounding the locale where the accident takes place. Some types of accidents correspond to low frequency-high consequence (long sick leaves) events, and then classical statistical approaches are ineffective in these cases because the available dataset is generally sparse and contain censored recordings. In this context, we propose a Bayesian population variability method for the estimation of the distributions of the rates of accident and recovery. Given these distributions, a Markov-based model will be used to estimate the uncertainty over the expected number of accidents and the work time loss. Thus, the use of Bayesian analysis along with the Markov approach aims at investigating future trends regarding occupational accidents in a workplace as well as enabling a better management of the labor force and prevention efforts. One application example is presented in order to validate the proposed approach; this case uses available data gathered from a hydropower company in Brazil. - Highlights: • This paper proposes a Bayesian method to estimate rates of accident and recovery. • The model requires simple data likely to be available in the company database. • These results show the proposed model is not too sensitive to the prior estimates.

  5. Defining constant versus variable phenotypic features of women with polycystic ovary syndrome using different ethnic groups and populations.

    Science.gov (United States)

    Welt, C K; Arason, G; Gudmundsson, J A; Adams, J; Palsdóttir, H; Gudlaugsdóttir, G; Ingadóttir, G; Crowley, W F

    2006-11-01

    The phenotype of women with polycystic ovary syndrome (PCOS) is variable, depending on the ethnic background. The phenotypes of women with PCOS in Iceland and Boston were compared. The study was observational with a parallel design. Subjects were studied in an outpatient setting. Women, aged 18-45 yr, with PCOS defined by hyperandrogenism and fewer than nine menses per year, were examined in Iceland (n = 105) and Boston (n = 262). PCOS subjects underwent a physical exam, fasting blood samples for androgens, gonadotropins, metabolic parameters, and a transvaginal ultrasound. The phenotype of women with PCOS was compared between Caucasian women in Iceland and Boston and among Caucasian, African-American, Hispanic, and Asian women in Boston. Androstenedione (4.0 +/- 1.3 vs. 3.5 +/- 1.2 ng/ml; P PCOS. There were no differences in fasting blood glucose, insulin, or homeostasis model assessment in body mass index-matched Caucasian subjects from Iceland or Boston or in different ethnic groups in Boston. Polycystic ovary morphology was demonstrated in 93-100% of women with PCOS in all ethnic groups. The data demonstrate differences in the reproductive features of PCOS without differences in glucose and insulin in body mass index-matched populations. These studies also suggest that measuring androstenedione is important for the documentation of hyperandrogenism in Icelandic women. Finally, polycystic ovary morphology by ultrasound is an almost universal finding in women with PCOS as defined by hyperandrogenism and irregular menses.

  6. Combination of Single Nucleotide Polymorphism and Variable-Number Tandem Repeats for Genotyping a Homogenous Population of Mycobacterium tuberculosis Beijing Strains in China

    OpenAIRE

    Luo, Tao; Yang, Chongguang; Gagneux, Sebastien; Gicquel, Brigitte; Mei, Jian; Gao, Qian

    2012-01-01

    The standard 15- and 24-locus variable-number tandem repeat (VNTR) genotyping methods have demonstrated adequate discriminatory power and a small homoplasy effect for tracing tuberculosis (TB) transmission and predicting Mycobacterium tuberculosis lineages in European and North American countries. However, its validity for the definition of transmission in homogenous M. tuberculosis populations in settings with high TB burdens has been questioned. Here, we genotyped a population-based collect...

  7. The association between insulin resistance, metabolic variables, and depressive symptoms in Mexican-American elderly: A population-based study.

    Science.gov (United States)

    Diniz, Breno S; Fisher-Hoch, Susan; McCormick, Joseph

    2018-02-01

    Depressive symptoms are common among older adults with obesity and diabetes. Nonetheless, the mechanisms for this association are not clear but may involve changes in the insulin cascade signaling. We aimed to investigate the association, and potential mediators, between obesity, insulin resistance, and depressive symptoms among older adults from a homogenous cohort of Mexican-Americans. We included a total of 500 Mexican-American older adults assessed in the Cameron County Health Study. We evaluated depressive symptoms using the Center for Epidemiologic Survey Depression Scale (CES-D). Central obesity was defined by waist circumference. Insulin resistance was evaluated by the HOMA-IR index. We estimated the association between obesity, insulin resistance, and depressive symptoms by carrying out univariate and multivariate regression analyses. In unadjusted regression analysis, HOMA-IR (unstandardized β = 0.31 ± 0.12, P = 0.007), waist circumference (unstandardized β = 0.066 ± 0.0.028, P = 0.017), and Hb1Ac levels (unstandardized β = 0.52 ± 0.24, P = 0.03) were significantly associated with CES-D scores. The association of HOMA-IR and CES-D remained statistically significant after controlling for socio-demographic and clinical variables in multivariate analysis (unstandardized β = 0.28 ± 0.11, P = 0.01). Our results suggest that depressive symptoms are associated with insulin resistance in older Mexican-American adults. In addition, poorer glucose control and obesity are important mediators of this relationship. Additional studies are needed to evaluate whether interventions that increase insulin sensitivity can also reduce depressive symptoms in this population. Copyright © 2017 John Wiley & Sons, Ltd.

  8. Conditions underpinning success in joint service-education workforce planning

    OpenAIRE

    Styles Laureen; Stevenson Lynn; Herringer Barbara; Purkis Mary; Van Neste-Kenny Jocelyne

    2009-01-01

    Abstract Vancouver Island lies just off the southwest coast of Canada. Separated from the large urban area of Greater Vancouver (estimated population 2.17 million) by the Georgia Strait, this geographical location poses unique challenges in delivering health care to a mixed urban, rural and remote population of approximately 730 000 people living on the main island and the surrounding Gulf Islands. These challenges are offset by opportunities for the Vancouver Island Health Authority (VIHA) t...

  9. Density dependence and climate effects in Rocky Mountain elk: an application of regression with instrumental variables for population time series with sampling error.

    Science.gov (United States)

    Creel, Scott; Creel, Michael

    2009-11-01

    1. Sampling error in annual estimates of population size creates two widely recognized problems for the analysis of population growth. First, if sampling error is mistakenly treated as process error, one obtains inflated estimates of the variation in true population trajectories (Staples, Taper & Dennis 2004). Second, treating sampling error as process error is thought to overestimate the importance of density dependence in population growth (Viljugrein et al. 2005; Dennis et al. 2006). 2. In ecology, state-space models are used to account for sampling error when estimating the effects of density and other variables on population growth (Staples et al. 2004; Dennis et al. 2006). In econometrics, regression with instrumental variables is a well-established method that addresses the problem of correlation between regressors and the error term, but requires fewer assumptions than state-space models (Davidson & MacKinnon 1993; Cameron & Trivedi 2005). 3. We used instrumental variables to account for sampling error and fit a generalized linear model to 472 annual observations of population size for 35 Elk Management Units in Montana, from 1928 to 2004. We compared this model with state-space models fit with the likelihood function of Dennis et al. (2006). We discuss the general advantages and disadvantages of each method. Briefly, regression with instrumental variables is valid with fewer distributional assumptions, but state-space models are more efficient when their distributional assumptions are met. 4. Both methods found that population growth was negatively related to population density and winter snow accumulation. Summer rainfall and wolf (Canis lupus) presence had much weaker effects on elk (Cervus elaphus) dynamics [though limitation by wolves is strong in some elk populations with well-established wolf populations (Creel et al. 2007; Creel & Christianson 2008)]. 5. Coupled with predictions for Montana from global and regional climate models, our results

  10. Variability and connectivity of plaice populations from the Eastern North Sea to the Baltic Sea, part II. Biological evidence of population mixing

    DEFF Research Database (Denmark)

    Ulrich, Clara; Hansen, Jakob Hemmer; Boje, Jesper

    2016-01-01

    in parallel. Genetic markers suggested the existence of different genetic populations in the transition area. Growth backcalculation with otoliths resulted in significant although limited differences in growth rates between North Sea and Skagerrak, indicating weak differentiation or important mixing......A multi-disciplinary study was conducted to clarify stock identity and connectivity patterns in the populations of European plaice (Pleuronectes platessa) in the Skagerrak-Kattegat transition area between the Eastern North Sea and the Baltic Sea. Five independent biological studies were carried out...... constitute a large share of the catches in this area. The mixing of different populations within a management area has implications for stock assessment and management. Choice must be made to either lump or split the populations, and the feasibility and constraints of both options are discussed. The outcomes...

  11. Genetic and Toxigenic Variability within Aspergillus flavus Population Isolated from Maize in Two Diverse Environments in Kenya

    Directory of Open Access Journals (Sweden)

    Sheila Okoth

    2018-01-01

    Full Text Available Aspergillus flavus is the main producer of carcinogenic aflatoxins in agricultural commodities such as maize. This fungus occurs naturally on crops, and produces aflatoxins when environmental conditions are favorable. The aim of this study is to analyse the genetic variability among 109 A. flavus isolates previously recovered from maize sampled from a known aflatoxin-hotspot (Eastern region, Kenya and the major maize-growing area in the Rift Valley (Kenya, and to determine their toxigenic potential. DNA analyses of internal transcribed spacer (ITS regions of ribosomal DNA, partial β-tubulin gene (benA and calmodulin gene (CaM sequences were used. The strains were further analyzed for the presence of four aflatoxin-biosynthesis genes in relation to their capability to produce aflatoxins and other metabolites, targeting the regulatory gene aflR and the structural genes aflP, aflD, and aflQ. In addition, the metabolic profile of the fungal strains was unraveled using state-of-the-art LC-MS/MS instrumentation. The three gene-sequence data grouped the isolates into two major clades, A. minisclerotigenes and A. flavus. A. minisclerotigenes was most prevalent in Eastern Kenya, while A. flavus was common in both regions. A. parasiticus was represented by a single isolate collected from Rift Valley. Diversity existed within the A. flavus population, which formed several subclades. An inconsistency in identification of some isolates using the three markers was observed. The calmodulin gene sequences showed wider variation of polymorphisms. The aflatoxin production pattern was not consistent with the presence of aflatoxigenic genes, suggesting an inability of the primers to always detect the genes or presence of genetic mutations. Significant variation was observed in toxin profiles of the isolates. This is the first time that a profound metabolic profiling of A. flavus isolates was done in Kenya. Positive associations were evident for some metabolites

  12. Genetic and Toxigenic Variability within Aspergillus flavus Population Isolated from Maize in Two Diverse Environments in Kenya.

    Science.gov (United States)

    Okoth, Sheila; De Boevre, Marthe; Vidal, Arnau; Diana Di Mavungu, José; Landschoot, Sofie; Kyallo, Martina; Njuguna, Joyce; Harvey, Jagger; De Saeger, Sarah

    2018-01-01

    Aspergillus flavus is the main producer of carcinogenic aflatoxins in agricultural commodities such as maize. This fungus occurs naturally on crops, and produces aflatoxins when environmental conditions are favorable. The aim of this study is to analyse the genetic variability among 109 A. flavus isolates previously recovered from maize sampled from a known aflatoxin-hotspot (Eastern region, Kenya) and the major maize-growing area in the Rift Valley (Kenya), and to determine their toxigenic potential. DNA analyses of internal transcribed spacer (ITS) regions of ribosomal DNA, partial β-tubulin gene (benA) and calmodulin gene (CaM) sequences were used. The strains were further analyzed for the presence of four aflatoxin-biosynthesis genes in relation to their capability to produce aflatoxins and other metabolites, targeting the regulatory gene aflR and the structural genes aflP, aflD, and aflQ. In addition, the metabolic profile of the fungal strains was unraveled using state-of-the-art LC-MS/MS instrumentation. The three gene-sequence data grouped the isolates into two major clades, A. minisclerotigenes and A. flavus . A. minisclerotigenes was most prevalent in Eastern Kenya, while A. flavus was common in both regions. A. parasiticus was represented by a single isolate collected from Rift Valley. Diversity existed within the A. flavus population, which formed several subclades. An inconsistency in identification of some isolates using the three markers was observed. The calmodulin gene sequences showed wider variation of polymorphisms. The aflatoxin production pattern was not consistent with the presence of aflatoxigenic genes, suggesting an inability of the primers to always detect the genes or presence of genetic mutations. Significant variation was observed in toxin profiles of the isolates. This is the first time that a profound metabolic profiling of A. flavus isolates was done in Kenya. Positive associations were evident for some metabolites, while for

  13. Probing the Perceptual and Cognitive Underpinnings of Braille Reading. An Estonian Population Study

    Science.gov (United States)

    Veispak, Anneli; Boets, Bart; Mannamaa, Mairi; Ghesquiere, Pol

    2012-01-01

    Similar to many sighted children who struggle with learning to read, a proportion of blind children have specific difficulties related to reading braille which cannot be easily explained. A lot of research has been conducted to investigate the perceptual and cognitive processes behind (impairments in) print reading. Very few studies, however, have…

  14. Conditions underpinning success in joint service-education workforce planning.

    Science.gov (United States)

    Purkis, Mary Ellen; Herringer, Barbara; Stevenson, Lynn; Styles, Laureen; Van Neste-Kenny, Jocelyne

    2009-02-25

    Vancouver Island lies just off the southwest coast of Canada. Separated from the large urban area of Greater Vancouver (estimated population 2.17 million) by the Georgia Strait, this geographical location poses unique challenges in delivering health care to a mixed urban, rural and remote population of approximately 730,000 people living on the main island and the surrounding Gulf Islands. These challenges are offset by opportunities for the Vancouver Island Health Authority (VIHA) to collaborate with four publicly funded post-secondary institutions in planning and implementing responses to existing and emerging health care workforce needs. In this commentary, we outline strategies we have found successful in aligning health education and training with local health needs in ways that demonstrate socially accountable outcomes. Challenges encountered through this process (i.e. regulatory reform, post-secondary policy reform, impacts of an ageing population, impact of private, for-profit educational institutions) have placed demands on us to establish and build on open and collaborative working relationships. Some of our successes can be attributed to evidence-informed decision-making. Other successes result from less tangible but no less important factors. We argue that both rational and "accidental" factors are significant--and that strategic use of "accidental" features may prove most significant in our efforts to ensure the delivery of high-quality health care to our communities.

  15. Conditions underpinning success in joint service-education workforce planning

    Directory of Open Access Journals (Sweden)

    Styles Laureen

    2009-02-01

    Full Text Available Abstract Vancouver Island lies just off the southwest coast of Canada. Separated from the large urban area of Greater Vancouver (estimated population 2.17 million by the Georgia Strait, this geographical location poses unique challenges in delivering health care to a mixed urban, rural and remote population of approximately 730 000 people living on the main island and the surrounding Gulf Islands. These challenges are offset by opportunities for the Vancouver Island Health Authority (VIHA to collaborate with four publicly funded post-secondary institutions in planning and implementing responses to existing and emerging health care workforce needs. In this commentary, we outline strategies we have found successful in aligning health education and training with local health needs in ways that demonstrate socially accountable outcomes. Challenges encountered through this process (i.e. regulatory reform, post-secondary policy reform, impacts of an ageing population, impact of private, for-profit educational institutions have placed demands on us to establish and build on open and collaborative working relationships. Some of our successes can be attributed to evidence-informed decision-making. Other successes result from less tangible but no less important factors. We argue that both rational and "accidental" factors are significant – and that strategic use of "accidental" features may prove most significant in our efforts to ensure the delivery of high-quality health care to our communities.

  16. Genetic variation of the greenhouse whitefly, Trialeurodes vaporariorum (Hemiptera: Aleyrodidae), among populations from Serbia and neighbouring countries, as inferred from COI sequence variability.

    Science.gov (United States)

    Prijović, M; Skaljac, M; Drobnjaković, T; Zanić, K; Perić, P; Marčić, D; Puizina, J

    2014-06-01

    The greenhouse whitefly Trialeurodes vaporariorum Westwood, 1856 (Hemiptera: Aleyrodidae) is an invasive and highly polyphagous phloem-feeding pest of vegetables and ornamentals. Trialeurodes vaporariorum causes serious damage due to direct feeding and transmits several important plant viruses. Excessive use of insecticides has resulted in significantly reduced levels of susceptibility of various T. vaporariorum populations. To determine the genetic variability within and among populations of T. vaporariorum from Serbia and to explore their genetic relatedness with other T. vaporariorum populations, we analysed the mitochondrial cytochrome c oxidase I (COI) sequences of 16 populations from Serbia and six neighbouring countries: Montenegro (three populations), Macedonia (one population) and Croatia (two populations), for a total of 198 analysed specimens. A low overall level of sequence divergence and only five variable nucleotides and six haplotypes were found. The most frequent haplotype, H1, was identified in all Serbian populations and in all specimens from distant localities in Croatia and Macedonia. The COI sequence data that was retrieved from GenBank and the data from our study indicated that H1 is the most globally widespread T. vaporariorum haplotype. A lack of spatial genetic structure among the studied T. vaporariorum populations, as well as two demographic tests that we performed (Tajima's D value and Fu's Fs statistics), indicate a recent colonisation event and population growth. Phylogenetic analyses of the COI haplotypes in this study and other T. vaporariorum haplotypes that were retrieved from GenBank were performed using Bayesian inference and median-joining (MJ) network analysis. Two major haplogroups with only a single unique nucleotide difference were found: haplogroup 1 (containing the five Serbian haplotypes and those previously identified in India, China, the Netherlands, the United Kingdom, Morocco, Reunion and the USA) and haplogroup 3

  17. Contact networks structured by sex underpin sex-specific epidemiology of infection.

    Science.gov (United States)

    Silk, Matthew J; Weber, Nicola L; Steward, Lucy C; Hodgson, David J; Boots, Mike; Croft, Darren P; Delahay, Richard J; McDonald, Robbie A

    2018-02-01

    Contact networks are fundamental to the transmission of infection and host sex often affects the acquisition and progression of infection. However, the epidemiological impacts of sex-related variation in animal contact networks have rarely been investigated. We test the hypothesis that sex-biases in infection are related to variation in multilayer contact networks structured by sex in a population of European badgers Meles meles naturally infected with Mycobacterium bovis. Our key results are that male-male and between-sex networks are structured at broader spatial scales than female-female networks and that in male-male and between-sex contact networks, but not female-female networks, there is a significant relationship between infection and contacts with individuals in other groups. These sex differences in social behaviour may underpin male-biased acquisition of infection and may result in males being responsible for more between-group transmission. This highlights the importance of sex-related variation in host behaviour when managing animal diseases. © 2017 The Authors. Ecology Letters published by CNRS and John Wiley & Sons Ltd.

  18. China's new oil import status underpins world's most dynamic petroleum scene

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    China is poised to become a net importer of oil in 1994--95. That sets the stage for China importing more than 1 million b/d of crude oil and refined products on a net basis by the turn of the century. That development underpins a bigger story -- arguably the biggest story on the petroleum scene today. The turnabout that is seeing the world's fifth biggest oil producer go from significant oil exporter in recent years to major oil importer by the turn of the century points to several other truisms in the petroleum industry: That an oil demand surge in the Asia-Pacific region led by China will fuel overall world oil demand growth for years to come; that a refining and petrochemical boom in a country that accounts for about one fifth of the world's population has dramatic implications for those two industries; that privatization has gathered so much momentum in the global petroleum industry that even Communist China has embraced some form of it; that China's domestic crude supply shortfall is creating unprecedented opportunities for foreign upstream investors in one of the world's most prospective yet underexplored and underexploited regions; and that the same new openness that is distinguishing China's petroleum industry today is turning some of its state owned companies into major competitors to be reckoned with on the international scene, upstream and downstream. The paper discusses China's oil export/import balance, supply/demand outlook, policy changes, and new regulations governing export of crude oil and products

  19. Inter-annual variability and long-term trends in breeding success in a declining population of migratory swans.

    NARCIS (Netherlands)

    Wood, K.A.; Newth, J.L.; Hilton, G.M.; Nolet, B.A.; Rees, E.C.

    2016-01-01

    Population declines among migratory Arctic-breeding birds are a growing concern for conservationists. To inform the conservation of these declining populations, we need to understand how demographic rates such as breeding success are influenced by combinations of extrinsic and intrinsic factors. In

  20. The Robust Running Ape: Unraveling the Deep Underpinnings of Coordinated Human Running Proficiency

    Directory of Open Access Journals (Sweden)

    John Kiely

    2017-06-01

    , misuse, and disuse—this spectrum of available ‘choice’ dysfunctionally contracts, and our capacity to safely disperse the mechanical ‘stress’ of running progressively diminishes. Now the running work burden falls increasingly on reduced populations of collaborating components. Accordingly our capacity to effectively manage, dissipate and accommodate running-imposed stress diminishes, and vulnerability to Overuse syndromes escalates. Awareness of the deep underpinnings of running coordination enhances conceptual clarity, thereby informing training and rehabilitation insights designed to offset the legacy of excessive or progressively accumulating exposure to running-imposed mechanical stress.

  1. Correcting Dayton's Oversight: Underpinning Bosnia's Democracy with the Rule of Law

    National Research Council Canada - National Science Library

    Thompson, Lewis

    1998-01-01

    .... The evidence is clear that the rule of law must underpin the construction of democracy, that the path to the rule of law is comprehensive legal reform, and that the police in a formerly authoritarian...

  2. Population genetic structure and life history variability in Oncorhynchus nerka from the Snake River basin. Final report

    International Nuclear Information System (INIS)

    Waples, R.S.; Aebersold, P.B.; Winans, G.A.

    1997-05-01

    The authors used protein electrophoresis to examine genetic relationships among samples of sockeye salmon and kokanee (Oncorhynchus nerka) from the Snake River basin. A few collections from elsewhere in the Pacific Northwest were also included to add perspective to the analysis. After combining temporal samples that did not differ statistically within and between years, 32 different populations were examined for variation at 64 gene loci scored in all populations. Thirty-five (55%) of these gene loci surveyed were polymorphic in at least one population. Average heterozygosities were relatively low (0.006--0.041), but genetic differentiation among populations was pronounced: the value of Wright's F ST of 0.244 is higher than has been reported in any other study of Pacific salmon

  3. Association of Lutzomyia longipalpis (Diptera: Psychodidae population density with climate variables in Montes Claros, an area of American visceral leishmaniasis transmission in the state of Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Érika Monteiro Michalsky

    2009-12-01

    Full Text Available In the present paper, we evaluate the relationship between climate variables and population density of Lutzomyia longipalpis in Montes Claros, an area of active transmission of American visceral leishmaniasis (AVL in Brazil. Entomological captures were performed in 10 selected districts of the city, between September 2002-August 2003. A total of 773 specimens of L. longipalpiswere captured in the period and the population density could be associated with local climate variables (cumulative rainfall, average temperature and relative humidity through a mathematical linear model with a determination coefficient (Rsqr of 0.752. Although based on an oversimplified statistical analysis, as far as the vector is concerned, this approach showed to be potentially useful as a starting point to guide control measures for AVL in Montes Claros.

  4. Association of Lutzomyia longipalpis (Diptera: Psychodidae) population density with climate variables in Montes Claros, an area of American visceral leishmaniasis transmission in the state of Minas Gerais, Brazil.

    Science.gov (United States)

    Michalsky, Erika Monteiro; Fortes-Dias, Consuelo Latorre; França-Silva, João Carlos; Rocha, Marilia Fonseca; Barata, Ricardo Andrade; Dias, Edelberto Santos

    2009-12-01

    In the present paper, we evaluate the relationship between climate variables and population density of Lutzomyia longipalpis in Montes Claros, an area of active transmission of American visceral leishmaniasis (AVL) in Brazil. Entomological captures were performed in 10 selected districts of the city, between September 2002-August 2003. A total of 773 specimens of L. longipalpiswere captured in the period and the population density could be associated with local climate variables (cumulative rainfall, average temperature and relative humidity) through a mathematical linear model with a determination coefficient (Rsqr) of 0.752. Although based on an oversimplified statistical analysis, as far as the vector is concerned, this approach showed to be potentially useful as a starting point to guide control measures for AVL in Montes Claros.

  5. Genetic Variability and Population Structure of the Potential Bioenergy Crop Miscanthus sinensis (Poaceae in Southwest China Based on SRAP Markers

    Directory of Open Access Journals (Sweden)

    Gang Nie

    2014-08-01

    Full Text Available The genus Miscanthus has great potential as a biofuel feedstock because of its high biomass, good burning quality, environmental tolerance, and good adaptability to marginal land. In this study, the genetic diversity and the relationship of 24 different natural Miscanthus sinensis populations collected from Southwestern China were analyzed by using 33 pairs of Sequence Related Amplified Polymorphism (SRAP primers. A total of 688 bands were detected with 646 polymorphic bands, an average of 19.58 polymorphic bands per primer pair. The average percentage of polymorphic loci (P, gene diversity (H, and Shannon’s diversity index (I among the 24 populations are 70.59%, 0.2589, and 0.3836, respectively. The mean value of total gene diversity (HT was 0.3373 ± 0.0221, while the allelic diversity within populations (HS was 0.2589 ± 0.0136 and the allelic diversity among populations (DST was 0.0784. The mean genetic differentiation coefficient (Gst = 0.2326 estimated from the detected 688 loci indicated that there was 76.74% genetic differentiation within the populations, which is consistent with the results from Analysis of Molecular Variance (AMOVA analysis. Based upon population structure and phylogenetic analysis, five groups were formed and a special population with mixed ancestry was inferred indicating that human-mediated dispersal may have had a significant effect on population structure of M. sinensis. Evaluating the genetic structure and genetic diversity at morphological and molecular levels of the wild M. sinensis in Southwest China is critical to further utilize the wild M. sinensis germplasm in the breeding program. The results in this study will facilitate the biofuel feedstock breeding program and germplasm conservation.

  6. Brief communication genotyping of Burkholderia pseudomallei revealed high genetic variability among isolates from a single population group

    OpenAIRE

    Zueter, Abdelrahman Mohammad; Rahman, Zaidah Abdul; Yean, Chan Yean; Harun, Azian

    2015-01-01

    Burkholderia pseudomallei is a soil dwelling Gram-negative bacteria predominates in Southeast Asia zone and the tropical part of Australia. Genetic diversity has been explored among various populations and environments worldwide. To date, little data is available on MLST profiling of clinical B. pseudomallei isolates in peninsular Malaysia. In this brief report, thirteen culture positive B. pseudomallei cases collected from a single population of Terengganu state in the Western Peninsular Mal...

  7. Energy-water-environment nexus underpinning future desalination sustainability

    KAUST Repository

    Shahzad, Muhammad Wakil

    2017-03-11

    Energy-water-environment nexus is very important to attain COP21 goal, maintaining environment temperature increase below 2°C, but unfortunately two third share of CO2 emission has already been used and the remaining will be exhausted by 2050. A number of technological developments in power and desalination sectors improved their efficiencies to save energy and carbon emission but still they are operating at 35% and 10% of their thermodynamic limits. Research in desalination processes contributing to fuel World population for their improved living standard and to reduce specific energy consumption and to protect environment. Recently developed highly efficient nature-inspired membranes (aquaporin & graphene) and trend in thermally driven cycle\\'s hybridization could potentially lower then energy requirement for water purification. This paper presents a state of art review on energy, water and environment interconnection and future energy efficient desalination possibilities to save energy and protect environment.

  8. Investigating the Effect of Recruitment Variability on Length-Based Recruitment Indices for Antarctic Krill Using an Individual-Based Population Dynamics Model

    Science.gov (United States)

    Thanassekos, Stéphane; Cox, Martin J.; Reid, Keith

    2014-01-01

    Antarctic krill (Euphausia superba; herein krill) is monitored as part of an on-going fisheries observer program that collects length-frequency data. A krill feedback management programme is currently being developed, and as part of this development, the utility of data-derived indices describing population level processes is being assessed. To date, however, little work has been carried out on the selection of optimum recruitment indices and it has not been possible to assess the performance of length-based recruitment indices across a range of recruitment variability. Neither has there been an assessment of uncertainty in the relationship between an index and the actual level of recruitment. Thus, until now, it has not been possible to take into account recruitment index uncertainty in krill stock management or when investigating relationships between recruitment and environmental drivers. Using length-frequency samples from a simulated population – where recruitment is known – the performance of six potential length-based recruitment indices is assessed, by exploring the index-to-recruitment relationship under increasing levels of recruitment variability (from ±10% to ±100% around a mean annual recruitment). The annual minimum of the proportion of individuals smaller than 40 mm (F40 min, %) was selected because it had the most robust index-to-recruitment relationship across differing levels of recruitment variability. The relationship was curvilinear and best described by a power law. Model uncertainty was described using the 95% prediction intervals, which were used to calculate coverage probabilities and assess model performance. Despite being the optimum recruitment index, the performance of F40 min degraded under high (>50%) recruitment variability. Due to the persistence of cohorts in the population over several years, the inclusion of F40 min values from preceding years in the relationship used to estimate recruitment in a given year improved its

  9. Evaluating within-population variability in behavior and demography for the adaptive potential of a dispersal-limited species to climate change

    Science.gov (United States)

    Muñoz, David J.; Miller Hesed, Kyle; Grant, Evan H. Campbell; Miller, David A.W.

    2016-01-01

    Multiple pathways exist for species to respond to changing climates. However, responses of dispersal-limited species will be more strongly tied to ability to adapt within existing populations as rates of environmental change will likely exceed movement rates. Here, we assess adaptive capacity in Plethodon cinereus, a dispersal-limited woodland salamander. We quantify plasticity in behavior and variation in demography to observed variation in environmental variables over a 5-year period. We found strong evidence that temperature and rainfall influence P. cinereus surface presence, indicating changes in climate are likely to affect seasonal activity patterns. We also found that warmer summer temperatures reduced individual growth rates into the autumn, which is likely to have negative demographic consequences. Reduced growth rates may delay reproductive maturity and lead to reductions in size-specific fecundity, potentially reducing population-level persistence. To better understand within-population variability in responses, we examined differences between two common color morphs. Previous evidence suggests that the color polymorphism may be linked to physiological differences in heat and moisture tolerance. We found only moderate support for morph-specific differences for the relationship between individual growth and temperature. Measuring environmental sensitivity to climatic variability is the first step in predicting species' responses to climate change. Our results suggest phenological shifts and changes in growth rates are likely responses under scenarios where further warming occurs, and we discuss possible adaptive strategies for resulting selective pressures.

  10. Metaphysical and value underpinnings of traditional medicine in West Africa.

    Science.gov (United States)

    Omonzejele, Peter F; Maduka, Chukwugozie

    2011-02-01

    This study investigated the extent to which recourse to traditional healers depended on biometric variables; ways of knowing in good time what ailments were more likely to be better handled by traditional healers; rationale behind traditional healing methodologies. On the whole, four research questions were engaged. The sample for the study included residents in urban (Benin City) and rural (Ehime Mbano) communities in Nigeria. The instruments comprised of two questionnaires. The traditional healers were also interviewed in addition. The findings of the research included the following: in both rural and urban areas, women and more elderly persons had more recourse than other groups to traditional medicine; Christians, less educated persons, self-employed persons and women affirmed most strongly to the efficacy of traditional medicine over Western medicine with respect to certain ailments; ways for averting spiritual illnesses included obeying instructions from ancestors and offering regular sacrifices to the gods; methods used by traditional healers to determine whether an ailment was "spiritual" or as a result of home problems included diagnosis linked to divination, interpretation of dreams particularly those involving visits by ancestors, interpretation of nightmares and omens such as the appearance of owls; methods for curing patients included use of herbs particularly those believed to have magical powers, offering of sacrifices, use of incantations and wearing of protective medicine.

  11. Chemical Composition of Juniperus communis L. Cone Essential Oil and Its Variability among Wild Populations in Kosovo.

    Science.gov (United States)

    Hajdari, Avni; Mustafa, Behxhet; Nebija, Dashnor; Miftari, Elheme; Quave, Cassandra L; Novak, Johannes

    2015-11-01

    Ripe cones of Juniperus communis L. (Cupressaceae) were collected from five wild populations in Kosovo, with the aim of investigating the chemical composition and natural variation of essential oils between and within wild populations. Ripe cones were collected, air dried, crushed, and the essential oils obtained by hydrodistillation. The essential-oil constituents were identified by GC-FID and GC/MS analyses. The yield of essential oil differed depending on the population origins and ranged from 0.4 to 3.8% (v/w, based on the dry weight). In total, 42 compounds were identified in the essential oils of all populations. The principal components of the cone-essential oils were α-pinene, followed by β-myrcene, sabinene, and D-limonene. Taking into consideration the yield and chemical composition, the essential oil originating from various collection sites in Kosovo fulfilled the minimum requirements for J. communis essential oils of the European Pharmacopoeia. Hierarchical cluster analysis (HCA) and principal component analysis (PCA) were used to determine the influence of the geographical variations on the essential-oil composition. These statistical analyses suggested that the clustering of populations was not related to their geographic location, but rather appeared to be linked to local selective forces acting on the chemotype diversity. Copyright © 2015 Verlag Helvetica Chimica Acta AG, Zürich.

  12. Cardiovascular disease, risk factors and heart rate variability in the elderly general population: Design and objectives of the CARdiovascular disease, Living and Ageing in Halle (CARLA Study

    Directory of Open Access Journals (Sweden)

    Kuss Oliver

    2005-11-01

    Full Text Available Abstract Background The increasing burden of cardiovascular diseases (CVD in the ageing population of industrialized nations requires an intensive search for means of reducing this epidemic. In order to improve prevention, detection, therapy and prognosis of cardiovascular diseases on the population level in Eastern Germany, it is necessary to examine reasons for the East-West gradient of CVD morbidity and mortality, potential causal mechanisms and prognostic factors in the elderly. Psychosocial and nutritional factors have previously been discussed as possible causes for the unexplained part of the East-West gradient. A reduced heart rate variability appears to be associated with cardiovascular disease as well as with psychosocial and other cardiovascular risk factors and decreases with age. Nevertheless, there is a lack of population-based data to examine the role of heart rate variability and its interaction with psychosocial and nutritional factors regarding the effect on cardiovascular disease in the ageing population. There also is a paucity of epidemiological data describing the health situation in Eastern Germany. Therefore, we conduct a population-based study to examine the distribution of CVD, heart rate variability and CVD risk factors and their associations in an elderly East German population. This paper describes the design and objectives of the CARLA Study. Methods/design For this study, a random sample of 45–80 year-old inhabitants of the city of Halle (Saale in Eastern Germany was drawn from the population registry. By the end of the baseline examination (2002–2005, 1750 study participants will have been examined. A multi-step recruitment strategy aims at achieving a 70 % response rate. Detailed information is collected on own and family medical history, socioeconomic, psychosocial, behavioural and biomedical factors. Medical examinations include anthropometric measures, blood pressure of arm and ankle, a 10-second and a 20

  13. Varying Herbivore Population Structure Correlates with Lack of Local Adaptation in a Geographic Variable Plant-Herbivore Interaction

    Science.gov (United States)

    Cogni, Rodrigo; Trigo, José R.; Futuyma, Douglas J.

    2011-01-01

    Local adaptation of parasites to their hosts due to coevolution is a central prediction of many theories in evolutionary biology. However, empirical studies looking for parasite local adaptation show great variation in outcomes, and the reasons for such variation are largely unknown. In a previous study, we showed adaptive differentiation in the arctiid moth Utetheisa ornatrix to its host plant, the pyrrolizidine alkaloid-bearing legume Crotalaria pallida, at the continental scale, but found no differentiation at the regional scale. In the present study, we sampled the same sites to investigate factors that may contribute to the lack of differentiation at the regional scale. We performed field observations that show that specialist and non-specialist polyphagous herbivore incidence varies among populations at both scales. With a series of common-garden experiments we show that some plant traits that may affect herbivory (pyrrolizidine alkaloids and extrafloral nectaries) vary at the regional scale, while other traits (trichomes and nitrogen content) just vary at the continental scale. These results, combined with our previous evidence for plant population differentiation based on larval performance on fresh fruits, suggest that U. ornatrix is subjected to divergent selection even at the regional scale. Finally, with a microsatellite study we investigated population structure of U. ornatrix. We found that population structure is not stable over time: we found population differentiation at the regional scale in the first year of sampling, but not in the second year. Unstable population structure of the herbivore is the most likely cause of the lack of regional adaptation. PMID:22220208

  14. Varying herbivore population structure correlates with lack of local adaptation in a geographic variable plant-herbivore interaction.

    Directory of Open Access Journals (Sweden)

    Rodrigo Cogni

    Full Text Available Local adaptation of parasites to their hosts due to coevolution is a central prediction of many theories in evolutionary biology. However, empirical studies looking for parasite local adaptation show great variation in outcomes, and the reasons for such variation are largely unknown. In a previous study, we showed adaptive differentiation in the arctiid moth Utetheisa ornatrix to its host plant, the pyrrolizidine alkaloid-bearing legume Crotalaria pallida, at the continental scale, but found no differentiation at the regional scale. In the present study, we sampled the same sites to investigate factors that may contribute to the lack of differentiation at the regional scale. We performed field observations that show that specialist and non-specialist polyphagous herbivore incidence varies among populations at both scales. With a series of common-garden experiments we show that some plant traits that may affect herbivory (pyrrolizidine alkaloids and extrafloral nectaries vary at the regional scale, while other traits (trichomes and nitrogen content just vary at the continental scale. These results, combined with our previous evidence for plant population differentiation based on larval performance on fresh fruits, suggest that U. ornatrix is subjected to divergent selection even at the regional scale. Finally, with a microsatellite study we investigated population structure of U. ornatrix. We found that population structure is not stable over time: we found population differentiation at the regional scale in the first year of sampling, but not in the second year. Unstable population structure of the herbivore is the most likely cause of the lack of regional adaptation.

  15. [Using IRAP markers for analysis of genetic variability in populations of resource and rare species of plants].

    Science.gov (United States)

    Boronnikova, S V; Kalendar', R N

    2010-01-01

    Species-specific LTR retrotransposons were first cloned in five rare relic species of drug plants located in the Perm' region. Sequences of LTR retrotransposons were used for PCR analysis based on amplification of repeated sequences from LTR or other sites of retrotransposons (IRAP). Genetic diversity was studied in six populations of rare relic species of plants Adonis vernalis L. by means of the IRAP method; 125 polymorphic IRAP-markers were analyzed. Parameters for DNA polymorphism and genetic diversity of A. vernalis populations were determined.

  16. Underpinning sustainable vector control through informed insecticide resistance management.

    Directory of Open Access Journals (Sweden)

    Edward K Thomsen

    Full Text Available There has been rapid scale-up of malaria vector control in the last ten years. Both of the primary control strategies, long-lasting pyrethroid treated nets and indoor residual spraying, rely on the use of a limited number of insecticides. Insecticide resistance, as measured by bioassay, has rapidly increased in prevalence and has come to the forefront as an issue that needs to be addressed to maintain the sustainability of malaria control and the drive to elimination. Zambia's programme reported high levels of resistance to the insecticides it used in 2010, and, as a result, increased its investment in resistance monitoring to support informed resistance management decisions.A country-wide survey on insecticide resistance in Zambian malaria vectors was performed using WHO bioassays to detect resistant phenotypes. Molecular techniques were used to detect target-site mutations and microarray to detect metabolic resistance mechanisms. Anopheles gambiae s.s. was resistant to pyrethroids, DDT and carbamates, with potential organophosphate resistance in one population. The resistant phenotypes were conferred by both target-site and metabolic mechanisms. Anopheles funestus s.s. was largely resistant to pyrethroids and carbamates, with potential resistance to DDT in two locations. The resistant phenotypes were conferred by elevated levels of cytochrome p450s.Currently, the Zambia National Malaria Control Centre is using these results to inform their vector control strategy. The methods employed here can serve as a template to all malaria-endemic countries striving to create a sustainable insecticide resistance management plan.

  17. Edaphic history over seedling characters predicts integration and plasticity of integration across geologically variable populations of Arabidopsis thaliana.

    Science.gov (United States)

    Cousins, Elsa A; Murren, Courtney J

    2017-12-01

    Studies on phenotypic plasticity and plasticity of integration have uncovered functionally linked modules of aboveground traits and seedlings of Arabidopsis thaliana , but we lack details about belowground variation in adult plants. Functional modules can be comprised of additional suites of traits that respond to environmental variation. We assessed whether shoot and root responses to nutrient environments in adult A. thaliana were predictable from seedling traits or population-specific geologic soil characteristics at the site of origin. We compared 17 natural accessions from across the native range of A. thaliana using 14-day-old seedlings grown on agar or sand and plants grown to maturity across nutrient treatments in sand. We measured aboveground size, reproduction, timing traits, root length, and root diameter. Edaphic characteristics were obtained from a global-scale dataset and related to field data. We detected significant among-population variation in root traits of seedlings and adults and in plasticity in aboveground and belowground traits of adult plants. Phenotypic integration of roots and shoots varied by population and environment. Relative integration was greater in roots than in shoots, and integration was predicted by edaphic soil history, particularly organic carbon content, whereas seedling traits did not predict later ontogenetic stages. Soil environment of origin has significant effects on phenotypic plasticity in response to nutrients, and on phenotypic integration of root modules and shoot modules. Root traits varied among populations in reproductively mature individuals, indicating potential for adaptive and integrated functional responses of root systems in annuals. © 2017 Botanical Society of America.

  18. Extended spawning in brown trout (Salmo trutta populations from the Southern Iberian Peninsula: the role of climate variability

    Directory of Open Access Journals (Sweden)

    José E. Larios-López

    2014-02-01

    Full Text Available The reproductive periods of brown trout (Salmo trutta populations in 12 rivers in the Baetic Mountains in southern Spain were studied from 2008 to 2013. This area is an ecological and geographical limit for the distribution of this species in Europe. We found that the spawning period has been markedly extended in these fish. The mean spawning dates in the studied populations are consistent with the European trend at this latitude, but our data suggest that females from most of the populations that we studied are able to produce eggs from early October through late April or early May, yielding a reproductive period of between 150 and 170 days, the longest and most delayed brown trout reproduction periods that have been reported in the literature. We believe that such expanded spawning periods result primarily from the unpredictability of the Mediterranean climate, although it is possible that other factors may have contributed to the development of this reproductive behaviour. This hypothesis is discussed in the context of a comparison of our results with those found for other European S. trutta populations.

  19. Leptin and variables of body adiposity, energy balance, and insulin resistance in a population-based study. The Hoorn Study

    NARCIS (Netherlands)

    Ruige, J B; Dekker, J M; Blum, W F; Stehouwer, C D; Nijpels, G; Mooy, J; Kostense, P J; Bouter, L M; Heine, R J

    OBJECTIVE: Leptin is thought to play a key role in the control of body weight. There is a complex interrelationship between leptin and insulin or insulin resistance, but it is unknown how leptin is regulated. We therefore explored, in a large population-based study of 2,484 Caucasian subjects aged

  20. Variability, heritability and genetic advance in F2 populations of aromatic rice involving induced mutants and Basmati varieties

    International Nuclear Information System (INIS)

    Hasib, K.M.; Ganguli, P.K.; Kole, P.C.

    2000-01-01

    The F 2 generation of five cross-combinations of aromatic rice involving two induced mutants 124-17-4 and 21-6-1 of aromatic tall Indica cultivar Gobindabhog and three basmati varieties was studied for mean performance, variability, heritability and genetic advance. The cross 21-6-1/Pakistan Basmati showed higher mean values for grain yield plant, and several yield components. Wide variability was observed for panicle number plant, filled grains panicle, test weight, dry matter production plant, harvest index and grain yield plant. Among the traits, filled grains panicle and test weight in all the crosses, grain yield plant, in five crosses and harvest index in two crosses had high heritability coupled with high genetic advance indicating predominant role of additive gene action. The crosses 21-6-1/Pakistan Basmati and 124-17-4/Pusa Basmati I could be exploited for isolation of promising aromatic recombinants. (author)

  1. Paleoecological studies on variability in marine fish populations: A long-term perspective on the impacts of climatic change on marine ecosystems

    Science.gov (United States)

    Finney, Bruce P.; Alheit, Jürgen; Emeis, Kay-Christian; Field, David B.; Gutiérrez, Dimitri; Struck, Ulrich

    2010-02-01

    The use of historical fishing records to understand relationships between climatic change and fish abundance is limited by the relatively short duration of these records, and complications due to the strong influence of human activity in addition to climatic change. Sedimentary records containing scales, bones or geochemical proxies of variability in fish populations provide unique insights on long-term ecosystem dynamics and relationships with climatic change. Available records from Holocene sediments are summarized and synthesized. The records are from several widespread locations near or along the continental margins of the South Atlantic and Pacific oceans, including Alaska, USA (Pacific salmon), Saanich and Effingham Inlets, British Columbia, Canada (pelagic fish), Santa Barbara Basin, California, USA (Northern anchovies and Pacific sardines), Gulf of California, Mexico (Pacific sardines, Northern anchovies and Pacific hake), Peru upwelling system (sardines, anchovies and hake), and Benguela Current System, South Africa (sardines, anchovies and hake). These records demonstrate that fish population sizes are not constant, and varied significantly over a range of time scales prior to the advent of large-scale commercial fishing. In addition to the decadal-scale variability commonly observed in historical records, the long-term records reveal substantial variability over centennial and millennial time scales. Shifts in abundance are often, but not always, correlated with regional and/or global climatic changes. The long-term perspective reveals different patterns of variability in fish populations, as well as fish-climate relationships, than suggested by analysis of historical records. Many records suggest prominent changes in fish abundance at ca. 1000-1200 AD, during the Little Ice Age, and during the transition at the end of the Little Ice Age in the 19th century that may be correlative, and that were likely driven by major hemispheric or global

  2. The Impact of Different Habitat Conditions on the Variability of Wild Populations of a Medicinal Plant Betonica officinalis L.

    Directory of Open Access Journals (Sweden)

    Kinga Kostrakiewicz-Gierałt

    2015-06-01

    Full Text Available Plants are important source of beneficial bioactive compounds which may find various applications as functional ingredients, such as components of food supplements, cosmetics, and pharmaceuticals. One such medicinal plant is Betonica officinalis, populations of which were investigated in 2012‒13. The studies were conducted in patches of Molinietum caeruleae dominated by: small meadow taxa (patch I; the shrub willow Salix repens ssp. rosmarinifolia (patch II; large tussock grasses Deschampsia caespitosa and Molinia caerulaea (patch III; tall-growing macroforbs Filipendula ulmaria and Solidago canadensis (patch IV. Over successive patches, the average height of plant cover increased, as did soil moisture, while light availability at ground level decreased. Much greater abundance and density of the Betonica officinalis population were found in patches I, III and IV, while lower values for these parameters were noted in patch II. Individuals in pre-reproductive stages were absent during whole study period in all study plots, vegetative ramet clusters were observed in plots situated in patches I and III in the first year of observations, while only generative ramet clusters occurred in plots set in patches II and IV. The number of rosettes per ramet cluster, number and dimensions of rosette leaves, height of flowering stems, number of cauline leaves, length of inflorescences, as well as number and length of flowers increased gradually over successive patches, whereas the number of generative stems per ramet cluster did not differ remarkably among populations. On the basis of the performed studies it might be concluded that the condition of populations deteriorated from patches overgrown by large-tussock grasses and characterized by considerable share of native and alien tall-growing macroforbs, via patch dominated by small meadow taxa, to patch prevailed by shrub willows.

  3. Intraspecific niche models for ponderosa pine (Pinus ponderosa) suggest potential variability in population-level response to climate change

    Science.gov (United States)

    Maguire, Kaitlin C.; Shinneman, Douglas; Potter, Kevin M.; Hipkins, Valerie D.

    2018-01-01

    Unique responses to climate change can occur across intraspecific levels, resulting in individualistic adaptation or movement patterns among populations within a given species. Thus, the need to model potential responses among genetically distinct populations within a species is increasingly recognized. However, predictive models of future distributions are regularly fit at the species level, often because intraspecific variation is unknown or is identified only within limited sample locations. In this study, we considered the role of intraspecific variation to shape the geographic distribution of ponderosa pine (Pinus ponderosa), an ecologically and economically important tree species in North America. Morphological and genetic variation across the distribution of ponderosa pine suggest the need to model intraspecific populations: the two varieties (var. ponderosa and var. scopulorum) and several haplotype groups within each variety have been shown to occupy unique climatic niches, suggesting populations have distinct evolutionary lineages adapted to different environmental conditions. We utilized a recently-available, geographically-widespread dataset of intraspecific variation (haplotypes) for ponderosa pine and a recently-devised lineage distance modeling approach to derive additional, likely intraspecific occurrence locations. We confirmed the relative uniqueness of each haplotype-climate relationship using a niche-overlap analysis, and developed ecological niche models (ENMs) to project the distribution for two varieties and eight haplotypes under future climate forecasts. Future projections of haplotype niche distributions generally revealed greater potential range loss than predicted for the varieties. This difference may reflect intraspecific responses of distinct evolutionary lineages. However, directional trends are generally consistent across intraspecific levels, and include a loss of distributional area and an upward shift in elevation. Our results

  4. Intraspecific niche models for ponderosa pine (Pinus ponderosa) suggest potential variability in population-level response to climate change.

    Science.gov (United States)

    Maguire, Kaitlin C; Shinneman, Douglas J; Potter, Kevin M; Hipkins, Valerie D

    2018-03-14

    Unique responses to climate change can occur across intraspecific levels, resulting in individualistic adaptation or movement patterns among populations within a given species. Thus, the need to model potential responses among genetically distinct populations within a species is increasingly recognized. However, predictive models of future distributions are regularly fit at the species level, often because intraspecific variation is unknown or is identified only within limited sample locations. In this study, we considered the role of intraspecific variation to shape the geographic distribution of ponderosa pine (Pinus ponderosa), an ecologically and economically important tree species in North America. Morphological and genetic variation across the distribution of ponderosa pine suggest the need to model intraspecific populations: the two varieties (var. ponderosa and var. scopulorum) and several haplotype groups within each variety have been shown to occupy unique climatic niches, suggesting populations have distinct evolutionary lineages adapted to different environmental conditions. We utilized a recently-available, geographically-widespread dataset of intraspecific variation (haplotypes) for ponderosa pine and a recently-devised lineage distance modeling approach to derive additional, likely intraspecific occurrence locations. We confirmed the relative uniqueness of each haplotype-climate relationship using a niche-overlap analysis, and developed ecological niche models (ENMs) to project the distribution for two varieties and eight haplotypes under future climate forecasts. Future projections of haplotype niche distributions generally revealed greater potential range loss than predicted for the varieties. This difference may reflect intraspecific responses of distinct evolutionary lineages. However, directional trends are generally consistent across intraspecific levels, and include a loss of distributional area and an upward shift in elevation. Our results

  5. Comparison of fermentation of diets of variable composition and microbial populations in the rumen of sheep and Rusitec fermenters. II. Protozoa population and diversity of bacterial communities.

    Science.gov (United States)

    Martínez, M E; Ranilla, M J; Tejido, M L; Saro, C; Carro, M D

    2010-08-01

    Four ruminally and duodenally cannulated sheep and 8 Rusitec fermenters were used to determine the effects of dietary characteristics on microbial populations and bacterial diversity. The purpose of the study was to assess how closely fermenters can mimic the differences between diets found in vivo. The 4 experimental diets contained forage to concentrate (F:C) ratios of 70:30 (high forage; HF) or 30:70 (high concentrate; HC) with either alfalfa hay (A) or grass hay (G) as the forage. Total bacterial numbers were greater in the rumen of sheep fed HF diets compared with those fed HC diets, whereas the opposite was found in fermenters. The numbers of cellulolytic bacteria were not affected by F:C ratio in any fermentation system, but cellulolytic numbers were 2.7 and 1.8 times greater in sheep than in fermenters for HF and HC diets, respectively. Neither total bacterial nor cellulolytic numbers were affected by the type of forage in sheep or fermenters. Decreasing F:C ratio increased total protozoa and Entodiniae numbers in sheep by about 29 and 25%, respectively, but it had no effect in fermenters. Isotrichidae and Ophryoscolecinae numbers in sheep were not affected by changing F:C ratio, but both disappeared completely from fermenters fed HC diets. Total protozoa and Entodiniae numbers were greater in sheep fed A diets than in those fed G diets, whereas the opposite was found in fermenters. Results indicate that under the conditions of the present study, protozoa population in Rusitec fermenters was not representative of that in the rumen of sheep fed the same diets. In addition, protozoa numbers in fermenters were 121 and 226 times lower than those in the sheep rumen for HF and HC diets, respectively. The automated ribosomal intergenic spacer analysis of the 16S ribosomal DNA was used to analyze the diversity of liquid- and solid-associated bacteria in both systems. A total of 170 peaks were detected in the automated ribosomal intergenic spacer analysis

  6. Variability of kokanee and rainbow trout food habits, distribution, and population dynamics, in an ultraoligotrophic lake with no manipulative management

    Science.gov (United States)

    Buktenica, M.W.; Girdner, S.F.; Larson, G.L.; McIntire, C.D.

    2007-01-01

    Crater Lake is a unique environment to evaluate the ecology of introduced kokanee and rainbow trout because of its otherwise pristine state, low productivity, absence of manipulative management, and lack of lotic systems for fish spawning. Between 1986 and 2004, kokanee displayed a great deal of variation in population demographics with a pattern that reoccurred in about 10 years. We believe that the reoccurring pattern resulted from density dependent growth, and associated changes in reproduction and abundance, driven by prey resource limitation that resulted from low lake productivity exacerbated by prey consumption when kokanee were abundant. Kokanee fed primarily on small-bodied prey from the mid-water column; whereas rainbow trout fed on large-bodied prey from the benthos and lake surface. Cladoceran zooplankton abundance may be regulated by kokanee. And kokanee growth and reproductive success may be influenced by the availability of Daphnia pulicaria, which was absent in zooplankton samples collected annually from 1990 to 1995, and after 1999. Distribution and diel migration of kokanee varied over the duration of the study and appeared to be most closely associated with prey availability, maximization of bioenergetic efficiency, and fish density. Rainbow trout were less abundant than were kokanee and exhibited less variation in population demographics, distribution, and food habits. There is some evidence that the population dynamics of rainbow trout were in-part related to the availability of kokanee as prey. ?? 2007 Springer Science+Business Media B.V.

  7. Brief communication genotyping of Burkholderia pseudomallei revealed high genetic variability among isolates from a single population group.

    Science.gov (United States)

    Zueter, Abdelrahman Mohammad; Rahman, Zaidah Abdul; Yean, Chan Yean; Harun, Azian

    2015-01-01

    Burkholderia pseudomallei is a soil dwelling Gram-negative bacteria predominates in Southeast Asia zone and the tropical part of Australia. Genetic diversity has been explored among various populations and environments worldwide. To date, little data is available on MLST profiling of clinical B. pseudomallei isolates in peninsular Malaysia. In this brief report, thirteen culture positive B. pseudomallei cases collected from a single population of Terengganu state in the Western Peninsular Malaysia and were confirmed by In-house TTS1-PCR. Isolates were subjected for multi-locus sequence typing (MLST) to explore their genotypic diversity and to investigate for possible clonal clustering of a certain sequence type. Patient's clinical information was examined to investigate for clinical correlation among the different genotypes. In spite of small sample set, MLST results indicated predictive results; considerable genotypic diversity, predominance and novelty among B. pseudomallei collected over a single geographically-located population in Malaysia. Massive genotypic heterogeneity was observed; 8 different sequence types with predominance of sequence type 54 and discovery of two novel sequence types. However, no clear pathogenomic or organ tropism clonal relationships were predicted.

  8. Genetic variability in biochemical characters of Brazilian field populations of the Leishmania vector, Lutzomyia longipalpis (Diptera: Psychodidae).

    Science.gov (United States)

    Mukhopadhyay, J; Ghosh, K; Rangel, E F; Munstermann, L E

    1998-12-01

    The phlebotomine sand fly Lutzomyia longipalpis is the insect vector of visceral leishmaniasis, a protozoan disease of increasing incidence and distribution in Central and South America. Electrophoretic allele frequencies of 15 enzyme loci were compared among the L. longipalpis populations selected across its distribution range in Brazil. The mean heterozygosity of two colonized geographic strains (one each from Colombia and Brazil) were 6% and 13% respectively, with 1.6-1.9 alleles detected per locus. In contrast, among the seven widely separated field populations, the mean heterozygosity ranged from 11% to 16% with 2.1-2.9 alleles per locus. No locus was recovered that was diagnostic for any of the field populations. Allelic frequency differences among five field strains from the Amazon basin and eastern coastal Brazil were very low, with Nei's genetic distances of less than 0.01 separating them. The two inland and southerly samples from Minas Gerais (Lapinha) and Bahia (Jacobina) states were more distinctive with genetic distances of 0.024-0.038 and 0.038-0.059, respectively, when compared with the five other samples. These differences were the consequence of several high frequency alleles (glycerol-3-phosphate dehydrogenase [Gpd1.69] and phosphoglucomutase [Pgm1.69]) relatively uncommon in other strains. The low genetic distances, absence of diagnostic loci, and the distribution of genes in geographic space indicate L. longipalpis of Brazil to be a single, but genetically heterogeneous, polymorphic species.

  9. Socio-environmental variables associated with malnutrition and intestinal parasitoses in the child population of Misiones, Argentina.

    Science.gov (United States)

    Zonta, María L; Oyhenart, Evelia E; Navone, Graciela T

    2014-01-01

    The aim was to analyze the socio-environmental variables associated with malnutrition and intestinal parasitoses in children from Aristóbulo del Valle, Province of Misiones (Argentina). A cross-sectional study was performed in 2,291 schoolchildren (age, 4-14 years). Body weight and height were measured and body mass index was calculated. NHANES III reference was used to estimate the nutritional status-underweight, stunting, wasting, overweight, and obesity. The parasitological analysis was performed by fecal and anal brush samples. The socio-environmental variables were surveyed using a semi-structured questionnaire. These variables were processed by categorical principal component analysis (cat-PCA). The two first axes defined four subgroups of schoolchildren: three of these were associated with urban characteristics (high, middle, and periurban), whereas the remaining subgroup was considered rural. Stunting and parasitic infections occurred mainly in the periurban group, that is the group of higher socio-environmental vulnerability. On the other hand, the highest prevalence of overweight and obesity and the lowest parasitism was observed in the high urban group. The similarity between rural and middle urban groups in stunting prevalence reveals that cities are not healthier than rural environments. On the contrary, the fact that the rural group presents the lowest prevalence of overweight reaffirms that poverty and malnutrition are progressively moving from rural to urban areas, and that rural children have still more diverse and healthy diets favored by the consumption of homemade products (i.e., orchards, animal husbandry, etc.), placing them at an earlier stage of the nutrition transition. © 2014 Wiley Periodicals, Inc.

  10. Morphological variability of hairs in malva alcea l. (malvaceae) populations from central and eastern europe, and consideration of the status of malva excisa rchb

    International Nuclear Information System (INIS)

    Celka, Z.; Olejnik, N.; Szkudlarz, P.; Drapikowska, M.; Jusik, S.

    2015-01-01

    Among the relics of medieval cultivation, Malva alcea L. is one of the most thoroughly studied species. In Central and Eastern Europe, a similar taxon Malva excisa Rchb. It has been recognized. The key diagnostic characters used so far to distinguish the 2 species include the depth of petal sinus and types of stem hairs. This study was aimed to analyse the variability of stem and leaf hairs and their usefulness as diagnostic characters for both taxa. The research material was collected from 19 localities in Poland, Germany, Czech Republic, Belarus and Ukraine. Several types of hairs were observed on the stems and leaves of M. alcea: single, bifurcate and stellate. Single and bifurcate hairs were found on stems and leaves of plants from all the studied populations, more frequently on the lower part of the stem, as well as on the upper (adaxial) surface of the leaf. Stellate hairs, with 3-10 branches, were observed on stems, mainly in their upper parts, and on the lower (abaxial) surface of leaves. The principal component analysis for hairs from the upper and lower part of the stem showed that individuals from most of the studied populations were clustered in one large group and only single individuals from several different populations were outside this group. Based on the graphic presentation of the Manhattan distances, calculated with the use of the Ward method, 2 groups were distinguished, but they included a mixture of individuals from various populations and geographic regions. The studied populations are not distinguishable by their key morphological characters, so all samples can be considered as M. alcea. The results of this study show that Malva alcea is a highly variable species, and its specific morphological forms are not correlated with geographical or ecological factors. There are also scientific grounds to question the distinction of M. excisa as a separate species or subspecies. (author)

  11. First surveys on genetic variability and structure of field maple (Acer campestre L. in natural and managed populations in the landscape of central and southern Italy

    Directory of Open Access Journals (Sweden)

    Fulvio Ducci

    2010-12-01

    Full Text Available Normal 0 14 false false false MicrosoftInternetExplorer4 Four Tuscan populations (central Italy and three Italian populations from southern Italy (Campania were sampled to compare their genetic variability and genetic structure. In each geographical area one of the sampled populations is originated naturally in forest and used as a local reference. The remaining populations were originated artificially. Indeed, field maple was traditionally used in Italy to supply fresh fodder to animals in dry summer period as tree twigs or to train up grape trees in the fields edges. This tradition initiated  at the time of Etruscans and continued throughout the Roman partitioning of agriculture landscape. Biochemical markers were used to explore variability in the examined populations (5 enzyme systems by 11 loci. Results showed that the main amount of variation is due to the individual component as for most of the scattered hardwoods in Europe and that differentiation among populations for these neutral  traits is relatively low. On the other hand, the natural populations in both the geographical areas showed a very high level of panmittic equilibrium, whilst the artificial populations were really distant from this condition showing a high probability of “founder effect”. This could be determined by the former system of self-supplying reproductive material carried out by farmers, based on the wild offspring collection growing around few mother trees. Discussion is focused also on how handling the opportunity given by many hundreds kilometers of lines  in the agriculture landscape as a way of managing diversity for this species. st1\\:*{behavior:url(#ieooui } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabella normale"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso

  12. Genetic variability and population structure in loci related to milk production traits in native Argentine Creole and commercial Argentine Holstein cattle

    Directory of Open Access Journals (Sweden)

    Golijow C.D.

    1999-01-01

    Full Text Available Many cattle breeds have been subjected to high selection pressure for production traits. Consequently, population genetic structure and allelic distribution could differ in breeds under high selection pressure compared to unselected breeds. Analysis of k-casein, aS1-casein and prolactin gene frequencies was made for Argentine Creole (AC and Argentine Holstein (AH cattle herds. The calculated FST values measured the degree of genetic differentiation of subpopulations, depending on the variances of gene frequencies.The AC breed had considerably more variation among herds at the aS1-casein and k-casein loci. Conservation strategies should consider the entire AC population in order to maintain the genetic variability found in this native breed.

  13. Environmental variables and tree population structures in deciduous forests of central Brazil with different levels of logging

    Directory of Open Access Journals (Sweden)

    Daniel Luis Mascia Vieira

    2008-04-01

    Full Text Available Population structures of six tree species in three fragments of intact seasonal deciduous forest and three fragments disturbed by logging were studied in the northeastern Goiás. Forty random 400 m² plots were allocated in each fragment to survey plant population structures, number of stumps, cattle feces, burnt logs, and canopy openness. Soil cover by life forms was estimated in 1m² sub-plots. Lianas were abundant in intermediately logged fragments and invasive herbs in the most disturbed fragment. Cattle avoided dense herbaceous strata, such as liana tangles. Cavanillesia arborea, Eugenia dysenterica and Swartzia multijuga trees occurred at very low densities in all the fragments and their seedlings were practically absent, which might endanger their future populations in these fragments. Myracrodruon urundeuva, Tabebuia impetiginosa and Astronium fraxinifolium, the most logged species, had high density of seedlings in all the fragments. However, the highest density of saplings and juvenile individuals occurred in the most disturbed fragment.As estruturas populacionais de seis espécies de árvores foram estudadas em três fragmentos de floresta estacional decidual intactos e três fragmentos impactados pela exploração seletiva de madeira no nordeste goiano. Quarenta parcelas de 400m² foram estabelecidas em cada fragmento para a amostragem de populações, número de tocos, fezes de gado, troncos queimados e abertura de dossel. A cobertura do solo por formas de vida foi estimada em sub-parcelas de 1m². Lianas foram mais abundantes em fragmentos com perturbação intermediária, enquanto herbáceas invasoras no fragmento mais perturbado. Cavanillesia arborea, Eugenia dysenterica e Swartzia multijuga ocorreram em densidades muito baixas em todos os fragmentos e plântulas foram praticamente ausentes, o que pode ameaçar o futuro de suas populações. Myracrodruon urundeuva, Tabebuia impetiginosa e Astronium fraxinifolium, as espécies mais

  14. The influence of climate variability on polar bear (Ursus maritimus) and ringed seal (Pusa hispida) population dynamics

    DEFF Research Database (Denmark)

    Rosing-Asvid, A.

    2006-01-01

    Unusually high polar bear (Ursus maritimus Phipps, 1774) predation on ringed seal (Pusa hispida (Schreber, 1775)) pups and increased survival of polar bear cubs during mild springs is documented in published articles. Strong predation on newborn ringed seal pups in early spring, however, is likely...... to lower the overall energy intake of polar bears if ringed seal pups are their main food, because the energetic value of ringed seal pups increases 7-8 times during the 6 week lactation period. So although hunting success in early spring increases cub survival during the period after den emergence......,when they are most vulnerable, it is likely to increase the number of starving bears later in the season. This negative-feedback effect of strong spring predation will not occur in areas where other seal species are abundant during summer, and polar bears in such areas are likely to exhibit population growth during...

  15. Characterization of mandibular molar root and canal morphology using cone beam computed tomography and its variability in Belgian and Chilean population samples

    International Nuclear Information System (INIS)

    Torres, Andres; Jacobs, Reinhilde; Lambrechts, Paul; Brizuela, Claudia; Cabrera, Carolina; Concha, Guillermo; Pedemonte, Maria Eugenia

    2015-01-01

    This study used cone-beam computed tomography (CBCT) to characterize mandibular molar root and canal morphology and its variability in Belgian and Chilean population samples. We analyzed the CBCT images of 515 mandibular molars (257 from Belgium and 258 from Chile). Molars meeting the inclusion criteria were analyzed to determine (1) the number of roots; (2) the root canal configuration; (3) the presence of a curved canal in the cross-sectional image of the distal root in the mandibular first molar and (4) the presence of a C-shaped canal in the second mandibular molar. A descriptive analysis was performed. The association between national origin and the presence of a curved or C-shaped canal was evaluated using the chi-squared test. The most common configurations in the mesial root of both molars were type V and type III. In the distal root, type I canal configuration was the most common. Curvature in the cross-sectional image was found in 25% of the distal canals of the mandibular first molars in the Belgian population, compared to 11% in the Chilean population. The prevalence of C-shaped canals was 10% or less in both populations. In cases of unclear or complex root and canal morphology in the mandibular molars, CBCT imaging might assist endodontic specialists in making an accurate diagnosis and in treatment planning

  16. Comparison of variable region 3 sequences of human immunodeficiency virus type 1 from infected children with the RNA and DNA sequences of the virus populations of their mothers.

    Science.gov (United States)

    Scarlatti, G; Leitner, T; Halapi, E; Wahlberg, J; Marchisio, P; Clerici-Schoeller, M A; Wigzell, H; Fenyö, E M; Albert, J; Uhlén, M

    1993-01-01

    We have compared the variable region 3 sequences from 10 human immunodeficiency virus type 1 (HIV-1)-infected infants to virus sequences from the corresponding mothers. The sequences were derived from DNA of uncultured peripheral blood mononuclear cells (PBMC), DNA of cultured PBMC, and RNA from serum collected at or shortly after delivery. The infected infants, in contrast to the mothers, harbored homogeneous virus populations. Comparison of sequences from the children and clones derived from DNA of the corresponding mothers showed that the transmitted virus represented either a minor or a major virus population of the mother. In contrast to an earlier study, we found no evidence of selection of minor virus variants during transmission. Furthermore, the transmitted virus variant did not show any characteristic molecular features. In some cases the transmitted virus was more related to the virus RNA population of the mother and in other cases it was more related to the virus DNA population. This suggests that either cell-free or cell-associated virus may be transmitted. These data will help AIDS researchers to understand the mechanism of transmission and to plan strategies for prevention of transmission. PMID:8446584

  17. Quality of care and variability in lung cancer management across Belgian hospitals: a population-based study using routinely available data.

    Science.gov (United States)

    Vrijens, France; De Gendt, Cindy; Verleye, Leen; Robays, Jo; Schillemans, Viki; Camberlin, Cécile; Stordeur, Sabine; Dubois, Cécile; Van Eycken, Elisabeth; Wauters, Isabelle; Van Meerbeeck, Jan P

    2018-05-01

    To evaluate the quality of care for all patients diagnosed with lung cancer in Belgium based on a set of evidence-based quality indicators and to study the variability of care between hospitals. A retrospective study based on linked data from the cancer registry, insurance claims and vital status for all patients diagnosed with lung cancer between 2010 and 2011. Evidence-based quality indicators were identified from a systematic literature search. A specific algorithm to attribute patients to a centre was developed, and funnel plots were used to assess variability of care between centres. None. The proportion of patients who received appropriate care as defined by the indicator. Secondary outcome included the variability of care between centres. Twenty indicators were measured for a total of 12 839 patients. Good results were achieved for 60-day post-surgical mortality (3.9%), histopathological confirmation of diagnosis (93%) and for the use of PET-CT before treatment with curative intent (94%). Areas to be improved include the reporting of staging information to the Belgian Cancer Registry (80%), the use of brain imaging for clinical stage III patients eligible for curative treatment (79%), and the time between diagnosis and start of first active treatment (median 20 days). High variability between centres was observed for several indicators. Twenty-three indicators were found relevant but could not be measured. This study highlights the feasibility to develop a multidisciplinary set of quality indicators using population-based data. The main advantage of this approach is that not additional registration is required, but the non-measurability of many relevant indicators is a hamper. It allows however to easily point to areas of large variability in care.

  18. Genetic variability in Brazilian populations of Biomphalaria straminea complex detected by simple sequence repeat anchored polymerase chain reaction amplification

    Directory of Open Access Journals (Sweden)

    Caldeira Roberta L

    2001-01-01

    Full Text Available Biomphalaria glabrata, B. tenagophila and B. straminea are intermediate hosts of Schistosoma mansoni, in Brazil. The latter is of epidemiological importance in the northwest of Brazil and, due to morphological similarities, has been grouped with B. intermedia and B. kuhniana in a complex named B. straminea. In the current work, we have standardized the simple sequence repeat anchored polymerase chain reaction (SSR-PCR technique, using the primers (CA8RY and K7, to study the genetic variability of these species. The similarity level was calculated using the Dice coefficient and genetic distance using the Nei and Li coefficient. The trees were obtained by the UPGMA and neighbor-joining methods. We have observed that the most related individuals belong to the same species and locality and that individuals from different localities, but of the same species, present clear heterogeneity. The trees generated using both methods showed similar topologies. The SSR-PCR technique was shown to be very efficient in intrapopulational and intraspecific studies of the B. straminea complex snails.

  19. Forage Yield and Quality Performance of Rabi Cereals Sown Alone and In Blended Population of Variable Seed Ratios

    International Nuclear Information System (INIS)

    Tahir, M.; Zafar, N.

    2016-01-01

    Fodder crops are the main source of animal feed in Pakistan. However, the yield per acre is still far below than optimum production level of the livestock. From this perspective, a field trial was conducted using seeds of three cereal crops wheat, oat and barley sown alone and blended together at different seed proportions (100 percent: 0 percent, 75 percent + 25 percent, 50 percent + 50 percent and 25 percent + 75 percent) at the Agronomic Research Area, Department of Agronomy, University of Agriculture, Faisalabad, during 2013-14. The results showed that the crop mixtures and their variable seed ratios showed significant effects on fodder yield and quality traits. The maximum number of tillers, number of leaves plant/sup -1/, leaf area, crop growth rate, fresh weight plant/sup -1/, dry weight plant/sup -1/, green forage yield and dry matter yield were obtained in plots where barley was sown alone at 100 percent seed ratio. The highest crude fiber and total ash percentage was observed in plots where oat was sown alone at 100 percent seed ratio and crude protein percentage was highest when oat was blended together with barley at 75 percent + 25 percent seed ratios. (author)

  20. Transcription-associated mutational pressure in the Parvovirus B19 genome: Reactivated genomes contribute to the variability of viral populations.

    Science.gov (United States)

    Khrustalev, Vladislav Victorovich; Ermalovich, Marina Anatolyevna; Hübschen, Judith M; Khrustaleva, Tatyana Aleksandrovna

    2017-12-21

    In this study we used non-overlapping parts of the two long open reading frames coding for nonstructural (NS) and capsid (VP) proteins of all available sequences of the Parvovirus B19 subgenotype 1a genome and found out that the rates of A to G, C to T and A to T mutations are higher in the first long reading frame (NS) of the virus than in the second one (VP). This difference in mutational pressure directions for two parts of the same viral genome can be explained by the fact of transcription of just the first long reading frame during the lifelong latency in nonerythroid cells. Adenine deamination (producing A to G and A to T mutations) and cytosine deamination (producing C to T mutations) occur more frequently in transcriptional bubbles formed by DNA "plus" strand of the first open reading frame. These mutations can be inherited only in case of reactivation of the infectious virus due to the help of Adenovirus that allows latent Parvovirus B19 to start transcription of the second reading frame and then to replicate its genome by the rolling circle mechanism using the specific origin. Results of this study provide evidence that the genomes reactivated from latency make significant contributions to the variability of Parvovirus B19. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Temporal and kinematic variables for real-world falls harvested from lumbar sensors in the elderly population.

    Science.gov (United States)

    Bourke, A K; Klenk, J; Schwickert, L; Aminian, K; Ihlen, E A F; Helbostad, J L; Chiari, L; Becker, C

    2015-01-01

    Automatic fall detection will reduce the consequences of falls in the elderly and promote independent living, ensuring people can confidently live safely at home. Inertial sensor technology can distinguish falls from normal activities. However, fall data recorded from elderly people in real life. The FARSEEING project has compiled a database of real life falls from elderly people, to gain new knowledge about fall events. We have extracted temporal and kinematic parameters to further improve the development of fall detection algorithms. A total of 100 real-world falls were analysed. Subjects with a known fall history were recruited, inertial sensors were attached to L5 and a fall report, following a fall, was used to extract the fall signal. This data-set was examined, and variables were extracted that include upper and lower impact peak values, posture angle change during the fall and time of occurrence. These extracted parameters, can be used to inform the design of fall-detection algorithms for real-world falls detection in the elderly.

  2. New Multilocus Variable-Number Tandem-Repeat Analysis (MLVA) Scheme for Fine-Scale Monitoring and Microevolution-Related Study of Ralstonia pseudosolanacearum Phylotype I Populations

    Science.gov (United States)

    Guinard, Jérémy; Latreille, Anne; Guérin, Fabien; Poussier, Stéphane

    2016-01-01

    ABSTRACT Bacterial wilt caused by the Ralstonia solanacearum species complex (RSSC) is considered one of the most harmful plant diseases in the world. Special attention should be paid to R. pseudosolanacearum phylotype I due to its large host range, its worldwide distribution, and its high evolutionary potential. So far, the molecular epidemiology and population genetics of this bacterium are poorly understood. Until now, the genetic structure of the RSSC has been analyzed on the worldwide and regional scales. Emerging questions regarding evolutionary forces in RSSC adaptation to hosts now require genetic markers that are able to monitor RSSC field populations. In this study, we aimed to evaluate the multilocus variable-number tandem-repeat analysis (MLVA) approach for its ability to discriminate genetically close phylotype I strains and for population genetics studies. We developed a new MLVA scheme (MLVA-7) allowing us to genotype 580 R. pseudosolanacearum phylotype I strains extracted from susceptible and resistant hosts and from different habitats (stem, soil, and rhizosphere). Based on specificity, polymorphism, and the amplification success rate, we selected seven fast-evolving variable-number tandem-repeat (VNTR) markers. The newly developed MLVA-7 scheme showed higher discriminatory power than the previously published MLVA-13 scheme when applied to collections sampled from the same location on different dates and to collections from different locations on very small scales. Our study provides a valuable tool for fine-scale monitoring and microevolution-related study of R. pseudosolanacearum phylotype I populations. IMPORTANCE Understanding the evolutionary dynamics of adaptation of plant pathogens to new hosts or ecological niches has become a key point for the development of innovative disease management strategies, including durable resistance. Whereas the molecular mechanisms underlying virulence or pathogenicity changes have been studied thoroughly, the

  3. Inter population variability of frost-resistance in provenances of scot pines (Pinusylvestris L.R. hamata Steven in Turkey

    Directory of Open Access Journals (Sweden)

    Özel Halil Barış

    2016-01-01

    Full Text Available Frost-resistance variability of Scotch pine (Pinus sylvestris L. var. hamata Steven seedlings grown in nurseries conditions, originated from 10 provenances, have been analyzed. The provenances from Black Sea region, Central Anatolian region and Eastern Anatolian region in Turkey have been used in selection of seed zones. The results of frost-resistance tests indicated a strong relationship of implemented freezing degrees with injury degrees of Scotch pine needles and photosynthetic productivities. On the other hand, another significant relationship has been determined between chlorophyll fluorescence and ion leakage methods (r=-0.801. This result shows that those two methods can be safely used in determining the damages due to low temperatures. In frost resistance tests, Scotch pine seedlings from different provenances have been frozen at -10, -20, -30 and -40°C. According to the Duncan test results, it has been determined that damage increased as temperature decreased. The damage level at -10°C implementation is 3.5% which can be tolerated by plants. But when the temperature has been decreased to -20°C, the level of damage has increased to 51.25%. As a result of photosynthetic analyses in this phase, it has been determined that there is a statistically significant relationship between provenances and temperature levels. Under the light of those findings, they have determined that the photosynthetic productivity has significantly decreased at temperatures between -20°C and -40°C. This situation conforms to injury index values determined in this study. As a result of injury index and photosynthetic productivity tests used for determining the damage after frost-resistance tests, it has been determined that the provenances of Amasya-Kunduz, Bolu-Aladağ, Düzce-Yığılca, Samsun-Vezirköprü and Eskişehir-Çatacık are more sensitive to frost than other provenances.

  4. Relationship between serum selenium, sociodemographic variables, other trace elements and lipid profile in an adult Spanish population.

    Science.gov (United States)

    González-Estecha, Montserrat; Palazón-Bru, Irene; Bodas-Pinedo, Andrés; Trasobares, Elena; Palazón-Bru, Antonio; Fuentes, Manuel; Cuadrado-Cenzual, M Ángeles; Calvo-Manuel, Elpidio

    2017-09-01

    Several studies have shown an inverse relationship between selenium status and cardiovascular health, although epidemiologic evidence yielded by the randomized trials did not find a beneficial effect of selenium administration. The aim of this study was to analyze the association between serum selenium levels and lipid profile adjusted by age, sex and other associated factors among a general adult population in Spain. We recruited 372 hospital employee volunteers (60 men and 312 women) with a mean age of 47 (SD: 10.9), whom were given a standardized questionnaire. Serum selenium concentration was measured by electrothermal atomization atomic absorption spectrometry. Serum copper and zinc concentrations were measured using flame atomic absorption spectrometry. The mean of serum selenium was 79.5μg/L (SD: 11.7) with no sex-dependent differences. In the multivariate linear regression analysis, the associated factors with the mean levels of selenium were: age (β=0.223; CI 95%: 0.101-0.345), pselenium≥79.5μg/L were 1.98 (OR=1.98; CI 95% 1.17-3.35; p=0.011) and 2.04 times (OR=2.04; CI 95% 1.06-3.97; p=0.034) more likely to have cholesterol ≥200mg/dL and LDL-c ≥100mg/dL respectively than those with serum selenium selenium was positively associated with increased total and LDL cholesterol but not with HDL-c and triglycerides. More studies are needed in order to confirm the lower serum selenium findings in widows. Copyright © 2016 Elsevier GmbH. All rights reserved.

  5. Combining biological and psychosocial baseline variables did not improve prediction of outcome of a very-low-energy diet in a clinic referral population.

    Science.gov (United States)

    Sumithran, P; Purcell, K; Kuyruk, S; Proietto, J; Prendergast, L A

    2018-02-01

    Consistent, strong predictors of obesity treatment outcomes have not been identified. It has been suggested that broadening the range of predictor variables examined may be valuable. We explored methods to predict outcomes of a very-low-energy diet (VLED)-based programme in a clinically comparable setting, using a wide array of pre-intervention biological and psychosocial participant data. A total of 61 women and 39 men (mean ± standard deviation [SD] body mass index: 39.8 ± 7.3 kg/m 2 ) underwent an 8-week VLED and 12-month follow-up. At baseline, participants underwent a blood test and assessment of psychological, social and behavioural factors previously associated with treatment outcomes. Logistic regression, linear discriminant analysis, decision trees and random forests were used to model outcomes from baseline variables. Of the 100 participants, 88 completed the VLED and 42 attended the Week 60 visit. Overall prediction rates for weight loss of ≥10% at weeks 8 and 60, and attrition at Week 60, using combined data were between 77.8 and 87.6% for logistic regression, and lower for other methods. When logistic regression analyses included only baseline demographic and anthropometric variables, prediction rates were 76.2-86.1%. In this population, considering a wide range of biological and psychosocial data did not improve outcome prediction compared to simply-obtained baseline characteristics. © 2017 World Obesity Federation.

  6. The Practical and Theoretical Underpinning of Inclusion for College Students amidst Diverse Intersectionality

    Science.gov (United States)

    Jaymes, Mariyah

    2017-01-01

    American higher education is facing another major transition with escalating costs, an influx of diverse students, and an over all question about the return on investment for higher education. Within these complexities, this essay will consider the practical history and theoretical underpinning which inform the experience for students with complex…

  7. Perceived Sacrifice and Few Alternatives Commitments: The Motivational Underpinnings of Continuance Commitment's Subdimensions

    Science.gov (United States)

    Vandenberghe, Christian; Panaccio, Alexandra

    2012-01-01

    Using work on self-concepts and Conservation of Resources theory, the present research examined the motivational underpinnings of continuance commitment's subcomponents of perceived sacrifice and few alternatives. Study 1 (N=208) found job scope to be positively related to perceived sacrifice commitment, and negatively related to few alternatives…

  8. Wearing the T-shirt: an exploration of the ideological underpinnings ...

    African Journals Online (AJOL)

    The article explores the ideological underpinnings of those narratives in four sections: 1) Paper-thin facts presents certain attitudes about Africa and the African body that have come into currency in relation to colonialism; 2) A matter of mor(t)ality examines the relationship between morality and the mortality of the African ...

  9. Cognitive Underpinnings of Moral Reasoning in Adolescence: The Contribution of Executive Functions

    Science.gov (United States)

    Vera-Estay, E.; Dooley, J. J.; Beauchamp, M. H.

    2015-01-01

    Adolescence is a developmental period characterized by intense changes, which impact the interaction between individuals and their environments. Moral reasoning (MR) is an important skill during adolescence because it guides social decisions between right and wrong. Identifying the cognitive underpinnings of MR is essential to understanding the…

  10. Development of a Multiple Loci Variable Number of Tandem Repeats Analysis (MLVA) to Unravel the Intra-Pathovar Structure of Pseudomonas syringae pv. actinidiae Populations Worldwide

    Science.gov (United States)

    Ciarroni, Serena; Gallipoli, Lorenzo; Taratufolo, Maria C.; Butler, Margi I.; Poulter, Russell T. M.; Pourcel, Christine; Vergnaud, Gilles; Balestra, Giorgio M.; Mazzaglia, Angelo

    2015-01-01

    The bacterial canker of kiwifruit by Pseudomonas syringae pv. actinidiae is an emblematic example of a catastrophic disease of fruit crops. In 2008 a new, extremely virulent form of the pathogen emerged and rapidly devastated many Actinidia spp. orchards all over the world. In order to understand differences in populations within this pathovar and to elucidate their diffusion and movements on world scale, it is necessary to be able to quickly and on a routine basis compare new isolates with previous records. In this report a worldwide collection of 142 strains was analyzed by MLVA, chosen as investigative technique for its efficacy, reproducibility, simplicity and low cost. A panel of 13 Variable Number of Tandem Repeats (VNTR) loci was identified and used to describe the pathogen population. The MLVA clustering is highly congruent with the population structure as previously established by other molecular approaches including whole genome sequencing and correlates with geographic origin, time of isolation and virulence. For convenience, we divided the VNTR loci in two panels. Panel 1 assay, using six loci, recognizes 23 different haplotypes, clustered into ten complexes with highest congruence with previous classifications. Panel 2, with seven VNTR loci, provides discriminatory power. Using the total set of 13 VNTR loci, 58 haplotypes can be distinguished. The recent hypervirulent type shows very limited diversity and includes, beside the strains from Europe, New Zealand and Chile, a few strains from Shaanxi, China. A broad genetic variability is observed in China, but different types are also retrievable in Japan and Korea. The low virulent strains cluster together and are very different from the other MLVA genotypes. Data were used to generate a public database in MLVAbank. MLVA represents a very promising first-line assay for large-scale routine genotyping, prior to whole genome sequencing of only the most relevant samples. PMID:26262683

  11. Geographical and Temporal Variability in Susceptibility to Cry1F Toxin From Bacillus thuringiensis in Spodoptera frugiperda (Lepidoptera: Noctuidae) Populations in Brazil.

    Science.gov (United States)

    Farias, Juliano R; Horikoshi, Renato J; Santos, Antonio C; Omoto, Celso

    2014-12-01

    The genetically modified maize TC1507 event with the cry1F gene (Cry1F maize) has been used to control Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) in Brazil since the 2009-2010 cropping season. As part of the insect resistance management program, we conducted studies to determine the baseline susceptibility to Cry1F before the widespread planting of Cry1F maize. Subsequently, we evaluated the geographical and temporal variability of susceptibility to this toxin in populations of S. frugiperda collected from major maize-growing regions in Brazil. The baseline susceptibility to Cry1F was determined using a diet-overlay bioassay for a susceptible reference population and four field populations of S. frugiperda. We then monitored the susceptibility to Cry1F in 43 populations of S. frugiperda sampled in nine States of Brazil between 2011 and 2013. In the baseline study, the MIC50 (the concentration that inhibits molting to second instars in 50% of individuals) ranged from 3.59 to 72.47 ng Cry1F toxin per centimeter square. Based on the upper limit of the MIC99 value of the joint analysis from the baseline susceptibility data, the concentrations of 200 and 2,000 ng of Cry1F toxin per centimeter square were defined as diagnostic concentrations for potentially resistant individuals, and these were used to monitor the susceptibility of S. frugiperda to Cry1F. Survival at 2,000 ng Cry1F toxin per centimeter square increased significantly throughout the cropping seasons in S. frugiperda populations from São Paulo, Santa Catarina, Rio Grande do Sul, Bahia, Mato Grosso, Goiás, Mato Grosso do Sul, and Paraná. The highest survival (>50%) was reached in populations collected from Bahia, Mato Grosso, Goiás, Mato Grosso do Sul, and Paraná during the 2012-2013 cropping season. Therefore, a significant decrease in susceptibility to Cry1F was detected in S. frugiperda throughout cropping seasons, especially in regions with intensive maize production in Brazil

  12. Posttraumatic Growth in Populations with Posttraumatic Stress Disorder-A Systematic Review on Growth-Related Psychological Constructs and Biological Variables.

    Science.gov (United States)

    Schubert, Christine F; Schmidt, Ulrike; Rosner, Rita

    2016-11-01

    Posttraumatic growth (PTG) and Posttraumatic Stress Disorder (PTSD) are possible consequences of trauma. PTG is supposed to emerge from cognitive processes and can have functional and dysfunctional aspects. This systematic review aims to identify and evaluate publications assessing PTG in adults diagnosed with PTSD in order to analyse the relationship between both constructs, how PTG is related to specific psychological variables and if there are biological variables linked to PTG. This extended review evaluates the quality of measures applied and is the first to study PTG only in populations meeting full PTSD criteria. In addition, the relationship between PTG and other relevant constructs, such as openness, optimism and social support, is explored. Our systematic literature search identified 140 studies of which 19 fulfilled our inclusion criteria; most of them used the Post-Traumatic Growth Inventory. Results indicate that trauma survivors with PTSD exhibit more PTG than those without PTSD and that PTG can be intensified during the therapeutic process whereat it is unclear whether PTG is a desirable outcome of PTSD therapy. Positive correlations between PTG and PTSD are reported. For diagnosed populations, we could not find strong evidence of a quadratic relationship between PTG and PTSD, although some studies support this hypothesis. Findings regarding the association of PTG with psychological variables are heterogeneous. Only one study focused on PTG as well as on biological variables (salivary cortisol) but did not discuss possible links between these two so far unconnected research fields in PTSD. Copyright © 2015 John Wiley & Sons, Ltd. Trauma survivors with PTSD develop more PTG than those without PTSD, it remains unclear whether PTSD and PTG are curvilinearly related. PTG can be enhanced through PTSD therapy, nevertheless one must not assume that PTG is a favorable treatment outcome since we do not know if the development of PTG during therapy promotes

  13. Prevalence of Chronic Disabling Noncancer Pain and Associated Demographic and Medical Variables: A Cross-Sectional Survey in the General German Population.

    Science.gov (United States)

    Häuser, Winfried; Schmutzer, Gabriele; Hilbert, Anja; Brähler, Elmar; Henningsen, Peter

    2015-10-01

    In population surveys, up to 30% of participants reported chronic pain. Reports of chronic pain do not necessarily imply disability associated with pain. We assessed the prevalence of chronic disabling noncancer pain and associated demographic and medical variables in a sample of the general German population. A cross-sectional survey was conducted with 4360 people aged 14 years and above, who were representative of the German population. Measures were obtained for demographic variables, presence of chronic pain (based on the definition of the International Association for the Study of Pain), chronic pain stages (based on a chronic pain grade questionnaire), and disease load (based on the self-reported comorbidity questionnaire). Responses were received from 2508 people. The prevalence of chronic pain was 28.3% (95% [confidence interval] CI, 26.5%-30.1%). In all, 7.3% (95% CI, 5.9%-8.7%) of participants met the criteria of chronic disabling noncancer pain. Chronic disabling noncancer pain was associated with age above 65 years (odds ratios [OR]=4.81 [95% CI, 1.57-14.79]), low family income (OR=2.54 [95% CI, 1.36-4.74]), obesity (OR=3.58 [95% CI, 2.21-5.79]), heart disease (OR=2.23 [95% CI, 3.69-11.40]), stomach disease (OR=4.24 [95% CI, 2.12-8.49]), and rheumatic disease (OR=3.67 [95% CI, 2.16-6.23]) when compared with no chronic pain. Chronic disabling noncancer pain was associated with low family income (OR=2.29 [95% CI, 1.23-4.27]), obesity (OR=2.14 [95% CI, 1.30-3.52]), and depression (OR=3.26 [95% CI, 1.90-5.66]) when compared with chronic nondisabling noncancer pain. Prevalence rates of chronic disabling pain in the general population rather than prevalence rates of chronic pain might provide evidence in support of pain specialist care. The association of chronic disabling noncancer pain with mental disorders highlights the need for psychosocial services in chronic pain management.

  14. Intra-population variability of ocean acidification impacts on the physiology of Baltic blue mussels (Mytilus edulis): integrating tissue and organism response.

    Science.gov (United States)

    Stapp, L S; Thomsen, J; Schade, H; Bock, C; Melzner, F; Pörtner, H O; Lannig, G

    2017-05-01

    Increased maintenance costs at cellular, and consequently organism level, are thought to be involved in shaping the sensitivity of marine calcifiers to ocean acidification (OA). Yet, knowledge of the capacity of marine calcifiers to undergo metabolic adaptation is sparse. In Kiel Fjord, blue mussels thrive despite periodically high seawater PCO 2 , making this population interesting for studying metabolic adaptation under OA. Consequently, we conducted a multi-generation experiment and compared physiological responses of F1 mussels from 'tolerant' and 'sensitive' families exposed to OA for 1 year. Family classifications were based on larval survival; tolerant families settled at all PCO 2 levels (700, 1120, 2400 µatm) while sensitive families did not settle at the highest PCO 2 (≥99.8% mortality). We found similar filtration rates between family types at the control and intermediate PCO 2 level. However, at 2400 µatm, filtration and metabolic scope of gill tissue decreased in tolerant families, indicating functional limitations at the tissue level. Routine metabolic rates (RMR) and summed tissue respiration (gill and outer mantle tissue) of tolerant families were increased at intermediate PCO 2 , indicating elevated cellular homeostatic costs in various tissues. By contrast, OA did not affect tissue and routine metabolism of sensitive families. However, tolerant mussels were characterised by lower RMR at control PCO 2 than sensitive families, which had variable RMR. This might provide the energetic scope to cover increased energetic demands under OA, highlighting the importance of analysing intra-population variability. The mechanisms shaping such difference in RMR and scope, and thus species' adaptation potential, remain to be identified.

  15. Stable carbon isotope variability of bone collagen and hair within a modern population of red kangaroos (Macropus rufus) in south western Queensland: some implications for palaeoecological research

    International Nuclear Information System (INIS)

    Witt, G.B.

    1997-01-01

    Full text: Before any palaeo-reconstruction work can be attempted using stable isotope analysis of macropod remains it will be necessary to determine the nature of natural variability within contemporary populations. This research indicates that δ 13 C of bone collagen is strongly related to age. Furthermore, bone collagen δ 13 C not at equilibrium with dietary δ 13 C, as indicated by analysis of hair, until animals are several years old. These preliminary data suggest that in younger macropods most carbon in bone collagen has been derived via the mother's milk which may have undergone fractionation. These findings have significant implications for any palaeoecological research using bone or tooth. Teeth of macropods erupt from the rear of the jaw and move forward in molar progression. Since the rate of eruption is variable, and many of the forward molars are well formed while the joey is still at the pouch, teeth formed early in the life of a macropod may be isotopically distinct from those that develop later. This hypothesis is currently under investigation

  16. The lactase -13910C>T polymorphism (rs4988235) is associated with overweight/obesity and obesity-related variables in a population sample of Portuguese young adults.

    Science.gov (United States)

    Manco, L; Dias, H; Muc, M; Padez, C

    2017-01-01

    Several studies reported associations of the lactase gene (LCT) polymorphism -13910C>T (rs4988235) with obesity-related variables and obesity in adults. This study aimed to replicate previously reported associations in a population sample of Portuguese young adults. We genotyped 447 subjects from central and northern regions of Portugal (mean age 20.81±4.24 years) for the lactase variant -13910C>T (rs4988235), using TaqMan probes. Anthropometric variables (weight, height and body fat) were measured using standardized procedures and body mass index (BMI) (kg/m 2 ) was calculated. Frequency of genotypes was 35.8% CC (lactase nonpersistent, LNP), 48.1% CT and 16.1% TT, consistent with Hardy-Weinberg equilibrium (P=1). The frequency for the minor -13910 T allele was 0.402. Assuming a dominance model for the lactase persistence (LP) minor T-allele, linear regression models showed statistically significant associations between the LP genotype CT/TT and BMI, fat mass and weight (β=1.114, P=0.003; β=1.309, P=0.007 and β=2.67, P=0.021, respectively) after adjustment for age and sex. In concordance, logistic regression showed significant association between LP genotype CT/TT and overweight/obesity (OR=1.77; CI 1.08-2.92; P=0.023), as well as with high fat percentage ranges (OR=1.58; CI 1.01-2.46; P=0.041), when adjusting for age and sex. No significant interaction was obtained between the LCT polymorphism and physical activity for BMI (P int =0.454) or FAT % (P int =0.421). In the Portuguese sample of young adults, the lactase -13910C>T polymorphism revealed significant associations with the obesity-related anthropometric variables BMI, fat mass and weight, and previously observed associations with the obesity risk were also confirmed.

  17. Leptospira interrogans en una población canina del Gran Buenos Aires: variables asociadas con la seropositividad Leptospira interrogans in a canine population of Greater Buenos Aires: variables associated with seropositivity

    Directory of Open Access Journals (Sweden)

    Diana Rubel

    1997-08-01

    Full Text Available Se determinó la seroprevalencia de leptospirosis en una población canina suburbana con el objeto de analizar la asociación entre distintas variables individuales y ambientales y la seropositividad a leptospirosis. El estudio, de diseño transversal, se llevó a cabo durante julio de 1992 en un barrio del Gran Buenos Aires en el que viven unos 9 500 habitantes y una población canina de unos 2 000 animales. Se estudió una muestra aleatoria de 223 perros, de cada uno de los cuales se obtuvo una muestra de sangre. La ficha epidemiológica del animal se obtuvo por encuesta al ama de casa. Las determinaciones serológicas se realizaron por microaglutinación frente a 10 serotipos de Leptospira interrogans. Se halló seropositividad en 57% de los 223 perros examinados; 82% de los sueros positivos coaglutinaron con dos o más serotipos. Los serotipos detectados con mayor frecuencia fueron canicola y pyrogenes. La seroprevalencia en hembras fue menor que en machos (P We determined the seroprevalence of leptospirosis in a suburban canine population for the purpose of analyzing the association between different individual and environmental variables and seropositivity for leptospirosis. The study, which was cross-sectional, was performed in July 1992 in a neighborhood of Greater Buenos Aires with approximately 9 500 inhabitants and a canine population of around 2 000 animals. We studied a random sample of 223 dogs and obtained a blood sample from each. Each animal’s epidemiologic history was obtained by interviewing the housewife. Serologic measurements were performed by the microagglutination technique with the use of 10 different serotypes of Leptospira interrogans. Of the 223 dogs that were tested, 57% showed seropositivity; 82% of the positive sera coagglutinated with two or more serotypes. The most frequently detected serotypes were canicola and pyrogenes. Seroprevalence in females was less common than in males (P <0,05 and in puppies less than

  18. No association of defined variability in leptin, leptin receptor, adiponectin, proopiomelanocortin and ghrelin gene with food preferences in the Czech population.

    Science.gov (United States)

    Bienertova-Vasku, Julie; Bienert, Petr; Tomandl, Josef; Forejt, Martin; Vavrina, Martin; Kudelkova, Jana; Vasku, Anna

    2008-02-01

    Previously, it has been reported that mutations in the genes encoding for adipokines may be associated with impaired food intake and may serve as potential obesity biomarkers. The aim of this study was to investigate the possible associations of defined variability in leptin, leptin receptor, adiponectin, proopiomelanocortin and ghrelin genes with food preferences in the obese and non-obese Czech population and evaluate their potential as the obesity susceptibility genes. Using PCR followed by restriction analysis, we studied 185 volunteers. Basic anthropometrical characteristics associated to obesity were measured and the food intake was monitored using a 7-day record method. In the group of obese individuals, a subset of 34 morbidly obese patients was studied for plasma leptin and soluble leptin receptor levels. None of the examined polymorphisms was associated to anthropometrical or demographic characteristics of the study subjects. The Gln223Arg polymorphism within the leptin receptor gene was significantly associated with lower plasma leptin levels (the RR genotype being more frequent in patients with lower plasma leptin levels; P = 0.001). No associations of the examined polymorphisms with food preferences was observed. Based on our results, the examined polymorphisms in the adipokine genes do not seem to be the major risk factor for obesity development in the Czech population nor significantly affect food preferences.

  19. Marital status as a candidate moderator variable of male-female differences in sexual jealousy: the need for representative population samples.

    Science.gov (United States)

    Voracek, M

    2001-04-01

    Evolutionary psychological theories predict pronounced and universal male-female differences in sexual jealousy. Recent cross-cultural research, using the forced-choice jealousy items pioneered by Buss, et al., 1992, repeatedly found a large sex differential on these self-report measures: men significantly more often than women choose their mate's imagined sexual infidelity to be more distressing or upsetting to them than an imagined emotional infidelity. However, this body of evidence is solely based on undergraduate samples and does not take into account demographic factors. This study examined male-female differences in sexual jealousy in a community sample (N = 335, Eastern Austria). Within a logistic regression model, with other variables controlled for, marital status was a stronger predictor for sexual jealousy than respondents' sex. Contrary to previous research, the sex differential's effect size was only modest. These findings stress the pitfalls of prematurely generalizing evidence from undergraduate samples to the general population and the need for representative population samples in this research area.

  20. Morphological, Phenological And Agronomical Characterisation Of Variability Among Common Bean (Phaseolus Vulgaris L. Local Populations From The National Centre For Plant Genetic Resources: Polish Genebank

    Directory of Open Access Journals (Sweden)

    Boros Lech

    2014-12-01

    Full Text Available The main purpose of this work was to analyse the morphological, phenological and agronomical variability among common bean local populations from The National Centre for Plant Genetic Resources, Polish Genebank, in order to know the relation among them, and to identify potentially useful accessions for future production and breeding. A considerable genotypic variation for number of seeds per plant, number of pods per plant and weight of seeds per plant were found. Studied bean accessions differed significantly in terms of thousand seeds weight (TSW as well as severity of bacterial halo blight and anthracnose, the major bean diseases. The lowest genotypic diversity was found for the percentage of protein in the seeds, the length of the vegetation period and lodging. The cluster analysis allowed identification of five groups of bean accessions. Genotypes from the first cluster (POLPOD 98-77, KOS 002 and Raba cv. and from the second cluster (WUKR 06-573a, KRA 4, WUKR 06-0534 together with Prosna cv. are of the highest usefulness for breeding purposes. There was no grouping of local populations depending on region of origin.

  1. Towards developing understanding of the drivers, constraints from the consumption values underpinning participation in physical activity.

    OpenAIRE

    Kearns, PJ; Williams-Burnett, N; Skinner, H

    2012-01-01

    Overall participation rates in physical activity across the UK have remained relatively static since the mid 1980s, with attendant causes for concern about the inequality of participation rates amongst various target groups that may be worthy of specific investigation. Behaviour change models from the fields of leisure studies, consumer behaviour and social psychology offer conceptualisation of a notion of exchange underpinning the expectancy-value process, noting that, in order to facilitate...

  2. Genetic Diversity Studies Based on Morphological Variability, Pathogenicity and Molecular Phylogeny of the Sclerotinia sclerotiorum Population From Indian Mustard (Brassica juncea

    Directory of Open Access Journals (Sweden)

    Pankaj Sharma

    2018-06-01

    in a clade-specific manner. Together this analysis observed the existence of higher heterogeneity and genetic variability in S. sclerotiorum isolates collection and indicates the presence of clonal and sexual progenies of the pathogen in the mustard growing regions of India surveyed in this study. With a higher level of genetic variability and diversity among the S. sclerotiorum population needs robust screening approaches to identify the donor parent and utilize them in resistance breeding program for effectively counter the menace of stem rot disease in Brassica.

  3. Rothmund-Thomson Syndrome: Insights from New Patients on the Genetic Variability Underpinning Clinical Presentation and Cancer Outcome

    Directory of Open Access Journals (Sweden)

    Elisa A. Colombo

    2018-04-01

    Full Text Available Biallelic mutations in RECQL4 gene, a caretaker of the genome, cause Rothmund-Thomson type-II syndrome (RTS-II and confer increased cancer risk if they damage the helicase domain. We describe five families exemplifying clinical and allelic heterogeneity of RTS-II, and report the effect of pathogenic RECQL4 variants by in silico predictions and transcripts analyses. Complete phenotype of patients #39 and #42 whose affected siblings developed osteosarcoma correlates with their c.[1048_1049del], c.[1878+32_1878+55del] and c.[1568G>C;1573delT], c.[3021_3022del] variants which damage the helicase domain. Literature survey highlights enrichment of these variants affecting the helicase domain in patients with cancer outcome raising the issue of strict oncological surveillance. Conversely, patients #29 and #19 have a mild phenotype and carry, respectively, the unreported homozygous c.3265G>T and c.3054A>G variants, both sparing the helicase domain. Finally, despite matching several criteria for RTS clinical diagnosis, patient #38 is heterozygous for c.2412_2414del; no pathogenic CNVs out of those evidenced by high-resolution CGH-array, emerged as contributors to her phenotype.

  4. Mechanisms underpinning effective peer support: a qualitative analysis of interactions between expert peers and patients newly-diagnosed with bipolar disorder

    Directory of Open Access Journals (Sweden)

    Proudfoot Judith G

    2012-11-01

    Full Text Available Abstract Background The increasing burden on mental health services has led to the growing use of peer support in psychological interventions. Four theoretical mechanisms have been proposed to underpin effective peer support: advice grounded in experiential knowledge, social support, social comparison and the helper therapy principle. However, there has been a lack of studies examining whether these mechanisms are also evident in clinical populations in which interpersonal dysfunction is common, such as bipolar disorder. Method This qualitative study, conducted alongside a randomized controlled trial, examined whether the four mechanisms proposed to underpin effective peer support were expressed in the email exchange between 44 individuals newly-diagnosed with bipolar disorder and their Informed Supporters (n = 4, over the course of a supported online psychoeducation program for bipolar disorder. A total of 104 text segments were extracted and coded. The data were complemented by face-to-face interviews with three of the four Informed Supporters who participated in the study. Results Qualitative analyses of the email interchange and interview transcripts revealed rich examples of all four mechanisms. The data illustrated how the involvement of Informed Supporters resulted in numerous benefits for the newly-diagnosed individuals, including the provision of practical strategies for illness management as well as emotional support throughout the intervention. The Informed Supporters encouraged the development of positive relationships with mental health services, and acted as role models for treatment adherence. The Informed Supporters themselves reported gaining a number of benefits from helping, including a greater sense of connectedness with the mental health system, as well as a broader knowledge of illness management strategies. Conclusions Examples of the mechanisms underpinning effective peer support were found in the sample of emails from

  5. An analysis of factors associated with influenza, pneumoccocal, Tdap, and herpes zoster vaccine uptake in the US adult population and corresponding inter-state variability.

    Science.gov (United States)

    La, Elizabeth M; Trantham, Laurel; Kurosky, Samantha K; Odom, Dawn; Aris, Emmanuel; Hogea, Cosmina

    2018-02-01

    Despite longstanding recommendations for routine vaccination against influenza; pneumococcal; tetanus, diphtheria, acellular pertussis (Tdap); and herpes zoster (HZ) among the United States general adult population, vaccine uptake remains low. Understanding factors that influence adult vaccination and coverage variability beyond the national level are important steps toward developing targeted strategies for increasing vaccination coverage. A retrospective analysis was conducted using data from the Behavioral Risk Factor Surveillance System (2011-2014). Multivariable logistic regression modeling was employed to identify individual factors associated with vaccination (socio-demographics, health status, healthcare utilization, state of residence) and generate adjusted vaccination coverage and compliance estimates nationally and by state. Results indicated that multiple characteristics were consistently associated with a higher likelihood of vaccination across all four vaccines, including female sex, increased educational attainment, and annual household income. Model-adjusted vaccination coverage estimates varied widely by state, with inter-state variability for the most recent year of data as follows: influenza (aged ≥18 years) 30.2-49.5%; pneumococcal (aged ≥65 years) 64.0-74.7%; Tdap (aged ≥18 years) 18.7-46.6%; and HZ (aged ≥60 years) 21.3-42.9%. Model-adjusted compliance with age-appropriate recommendations across vaccines was low and also varied by state: influenza+Tdap (aged 18-59 years) 7.9-24.7%; influenza+Tdap+HZ (aged 60-64 years) 4.1-14.4%; and influenza+Tdap+HZ+pneumococcal (aged ≥65 years) 3.0-18.3%. In summary, after adjusting for individual characteristics associated with vaccination, substantial heterogeneity across states remained, suggesting that other local factors (e.g. state policies) may be impacting adult vaccines uptake. Further research is needed to understand such factors, focusing on differences between states with high versus

  6. Population-Level Transcriptomic Responses of the Southern Ocean Salp Salpa thompsoni to Environment Variability of the Western Antarctic Peninsula Region

    Science.gov (United States)

    Bucklin, A. C.; Batta Lona, P. G.; Maas, A. E.; O'Neill, R. J.; Wiebe, P. H.

    2015-12-01

    In response to the changing Antarctic climate, the Southern Ocean salp Salpa thompsoni has shown altered patterns of distribution and abundance that are anticipated to have profound impacts on pelagic food webs and ecosystem dynamics. The physiological and molecular processes that underlay ecological function and biogeographical distribution are key to understanding present-day dynamics and predicting future trajectories. This study examined transcriptome-wide patterns of gene expression in relation to biological and physical oceanographic conditions in coastal, shelf and offshore waters of the Western Antarctic Peninsula (WAP) region during austral spring and summer 2011. Based on field observations and collections, seasonal changes in the distribution and abundance of salps of different life stages were associated with differences in water mass structure of the WAP. Our observations are consistent with previous suggestions that bathymetry and currents in Bransfield Strait could generate a retentive cell for an overwintering population of S. thompsoni, which may generate the characteristic salp blooms found throughout the region later in summer. The statistical analysis of transcriptome-wide patterns of gene expression revealed differences among salps collected in different seasons and from different habitats (i.e., coastal versus offshore) in the WAP. Gene expression patterns also clustered by station in austral spring - but not summer - collections, suggesting stronger heterogeneity of environmental conditions. During the summer, differentially expressed genes covered a wider range of functions, including those associated with stress responses. Future research using novel molecular transcriptomic / genomic characterization of S. thompsoni will allow more complete understanding of individual-, population-, and species-level responses to environmental variability and prediction of future dynamics of Southern Ocean food webs and ecosystems.

  7. Multiple comorbidities of 21 psychological disorders and relationships with psychosocial variables: a study of the online assessment and diagnostic system within a web-based population.

    Science.gov (United States)

    Al-Asadi, Ali M; Klein, Britt; Meyer, Denny

    2015-02-26

    While research in the area of e-mental health has received considerable attention over the last decade, there are still many areas that have not been addressed. One such area is the comorbidity of psychological disorders in a Web-based sample using online assessment and diagnostic tools, and the relationships between comorbidities and psychosocial variables. We aimed to identify comorbidities of psychological disorders of an online sample using an online diagnostic tool. Based on diagnoses made by an automated online assessment and diagnostic system administered to a large group of online participants, multiple comorbidities (co-occurrences) of 21 psychological disorders for males and females were identified. We examined the relationships between dyadic comorbidities of anxiety and depressive disorders and the psychosocial variables sex, age, suicidal ideation, social support, and quality of life. An online complex algorithm based on the criteria of the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, Text Revision, was used to assign primary and secondary diagnoses of 21 psychological disorders to 12,665 online participants. The frequency of co-occurrences of psychological disorders for males and females were calculated for all disorders. A series of hierarchical loglinear analyses were performed to examine the relationships between the dyadic comorbidities of depression and various anxiety disorders and the variables suicidal ideation, social support, quality of life, sex, and age. A 21-by-21 frequency of co-occurrences of psychological disorders matrix revealed the presence of multiple significant dyadic comorbidities for males and females. Also, for those with some of the dyadic depression and the anxiety disorders, the odds for having suicidal ideation, reporting inadequate social support, and poorer quality of life increased for those with two-disorder comorbidity than for those with only one of the same two disorders. Comorbidities of

  8. [Patient first - The impact of characteristics of target populations on decisions about therapy effectiveness of complex interventions: Psychological variables to assess effectiveness in interdisciplinary multimodal pain therapy].

    Science.gov (United States)

    Kaiser, Ulrike; Sabatowski, Rainer; Balck, Friedrich

    2017-08-01

    The assessment of treatment effectiveness in public health settings is ensured by indicators that reflect the changes caused by specific interventions. These indicators are also applied in benchmarking systems. The selection of constructs should be guided by their relevance for affected patients (patient reported outcomes). The interdisciplinary multimodal pain therapy (IMPT) is a complex intervention based on a biopsychosocial understanding of chronic pain. For quality assurance purposes, psychological parameters (depression, general anxiety, health-related quality of life) are included in standardized therapy assessment in pain medicine (KEDOQ), which can also be used for comparative analyses in a benchmarking system. The aim of the present study was to investigate the relevance of depressive symptoms, general anxiety and mental quality of life in patients undergoing IMPT under real life conditions. In this retrospective, one-armed and exploratory observational study we used secondary data of a routine documentation of IMST in routine care, applying several variables of the German Pain Questionnaire and the facility's comprehensive basic documentation. 352 participants with IMPT (from 2006 to 2010) were included, and the follow-up was performed over two years with six assessments. Because of statistically heterogeneous characteristics a complex analysis consisting of factor and cluster analyses was applied to build subgroups. These subgroups were explored to identify differences in depressive symptoms (HADS-D), general anxiety (HADS-A), and mental quality of life (SF 36 PSK) at the time of therapy admission and their development estimated by means of effect sizes. Analyses were performed using SPSS 21.0®. Six subgroups were derived and mainly proved to be clinically and psychologically normal, with the exception of one subgroup that consistently showed psychological impairment for all three parameters. The follow-up of the total study population revealed medium

  9. Genetic Variability of the Glucose-Dependent Insulinotropic Peptide Gene Is Involved in the Premature Coronary Artery Disease in a Chinese Population with Type 2 Diabetes

    Directory of Open Access Journals (Sweden)

    Xiaowei Ma

    2018-01-01

    Full Text Available Background. Glucose-dependent insulinotropic polypeptide (GIP is closely related to diabetes and obesity, both of which are confirmed to increase the risk of coronary artery disease (CAD. Our study aimed to investigate whether the polymorphisms in GIP genes could affect the risk of cardiovascular disease in type 2 diabetic patients in the Chinese Han population. Methods. We selected and genotyped two haplotype-tagging single nucleotide polymorphisms (tag-SNPs (rs2291725 C>T, rs8078510 G>A of GIP gene based on CHB data in HapMap Phase II database (r2<0.8. The case-control study of Chinese Han population involved 390 diabetic patients with CAD as positive group and 276 diabetic patients without CAD as control group. Allele and genotype frequencies were compared between the two groups. Results. In dominant inheritance model, the carriers of T/T or T/C had a lower risk of CAD (OR = 0.635, 95% CI = 0.463–0.872, p=0.005, even after adjustment other CAD risk factors (gender, age, BMI, smoking status, dyslipidemia, hypertension history, and diabetic duration (OR′ = 0.769, 95% CI′ = 0.626–0.945, p′=0.013. The allele A at rs8078510 was associated with decreased risk of CAD (OR = 0.732, p=0.039. p=0.018 in subgroup analysis, individuals with higher BMI (≥24 kg/m2 had increased risk for CAD when carrying C/C at rs2291725 (OR′ = 1.291, 95% CI′ = 1.017–1.639, p′=0.036. In age < 55 men and age < 65 women, the carriers of allele C at rs2291725 had a higher risk of CAD than noncarriers (OR = 1.627, p=0.015. Carriers of allele G in rs8078510 had higher susceptibility to CAD (OR = 2.049, 95% = CI 1.213–3.463, p=0.007. p=0.004; in addition, allele G in rs8078510 would bring higher CAD risk to the carriers who ever smoked (OR = 1.695, 95% CI = 1.080–2.660, p=0.021. Conclusion. The genetic variability of GIP gene is associated with CAD and it may play a role in the premature CAD in the

  10. Understanding Population.

    Science.gov (United States)

    Mothner, Ira

    Activities and concerns of Ford Foundation supported population research and training centers are described in this report. The centers are concerned with population growth, consequences of growth for human welfare, forces that determine family planning, interrelations among population variables, economics of contraceptive distribution, and…

  11. The philosophical and pedagogical underpinnings of Active Learning in Engineering Education

    Science.gov (United States)

    Christie, Michael; de Graaff, Erik

    2017-01-01

    In this paper the authors draw on three sequential keynote addresses that they gave at Active Learning in Engineering Education (ALE) workshops in Copenhagen (2012), Caxias do Sol (2014) and San Sebastian (2015). Active Learning in Engineering Education is an informal international network of engineering educators dedicated to improving engineering education through active learning (http://www.ale-net.org/). The paper reiterates themes from those keynotes, namely, the philosophical and pedagogical underpinnings of Active Learning in Engineering Education, the scholarly questions that inspire engineering educators to go on improving their practice and exemplary models designed to activate the learning of engineering students. This paper aims to uncover the bedrock of established educational philosophies and theories that define and support active learning. The paper does not claim to present any new or innovative educational theory. There is already a surfeit of them. Rather, the aim is to assist Engineering Educators who wish to research how they can best activate the learning of their students by providing a readable, reasonable and solid underpinning for best practice in this field.

  12. Prevalence of asthma with airflow limitation, COPD, and COPD with variable airflow limitation in older subjects in a general Japanese population: the Hisayama Study.

    Science.gov (United States)

    Matsumoto, Koichiro; Seki, Nanae; Fukuyama, Satoru; Moriwaki, Atsushi; Kan-o, Keiko; Matsunaga, Yuko; Noda, Naotaka; Yoshida, Makoto; Koto, Hiroshi; Takata, Shohei; Nakanishi, Yoichi; Kiyohara, Yutaka; Inoue, Hiromasa

    2015-01-01

    Elucidating the prevalence of asthma and chronic obstructive pulmonary disease (COPD) is important for designing a public health strategy. Recent studies have discriminated a phenotype of COPD with variable airflow limitation (COPD-VAL) associated with asthma-COPD overlap syndrome. Its prevalence remains uncertain. The age and occupational distributions in the town of Hisayama and in Japan are nearly identical. Each disease's prevalence was estimated for the town's residents. In 2008, town residents (≥ 40 years) were solicited to participate in a health checkup. Individuals with abnormal spirometry (forced expiratory volume in 1s/forced vital capacity [FEV1/FVC]fashion reviewed their medical records, including bronchodilator reversibility. Individuals with airflow limitation were classified as having asthma, COPD, COPD-VAL, or other diseases. The prevalence of each disease was then estimated. A total of 2100 residents (43.4% of residents in the age group) completed spirometry. In 455 residents with abnormal spirometry, 190 residents had further evaluations, and the medical records of 174 residents were reviewed. The prevalence of asthma with airflow limitation, COPD, and COPD-VAL, were 2.0%, 8.4%, and 0.9%, respectively. The prevalence of COPD and COPD-VAL were higher in men and smokers than in women and never-smokers. The prevalence of COPD, but not COPD-VAL or asthma, increased with age. The prevalence of asthma with airflow limitation, COPD, and COPD-VAL were estimated in a population of residents (≥ 40 years) in Hisayama. Copyright © 2014 The Japanese Respiratory Society. Published by Elsevier B.V. All rights reserved.

  13. Unified underpinning of human mobility in the real world and cyberspace

    Science.gov (United States)

    Zhao, Yi-Ming; Zeng, An; Yan, Xiao-Yong; Wang, Wen-Xu; Lai, Ying-Cheng

    2016-05-01

    Human movements in the real world and in cyberspace affect not only dynamical processes such as epidemic spreading and information diffusion but also social and economical activities such as urban planning and personalized recommendation in online shopping. Despite recent efforts in characterizing and modeling human behaviors in both the real and cyber worlds, the fundamental dynamics underlying human mobility have not been well understood. We develop a minimal, memory-based random walk model in limited space for reproducing, with a single parameter, the key statistical behaviors characterizing human movements in both cases. The model is validated using relatively big data from mobile phone and online commerce, suggesting memory-based random walk dynamics as the unified underpinning for human mobility, regardless of whether it occurs in the real world or in cyberspace.

  14. The relational underpinnings of quality internal auditing in medical clinics in Israel.

    Science.gov (United States)

    Carmeli, Abraham; Zisu, Malka

    2009-03-01

    Internal auditing is a key mechanism in enhancing organizational reliability. However, research on the ways quality internal auditing is enabled through learning, deterrence, motivation and process improvement is scant. In particular, the relational underpinnings of internal auditing have been understudied. This study attempts to address this need by examining how organizational trust, perceived organizational support and psychological safety enable internal auditing. Data collected from employees in medical clinics of one of the largest healthcare organizations in Israel at two points in time six months apart. Our results show that organizational trust and perceived organizational support are positively related to psychological safety (measured at time 1), which, in turn, is associated with internal auditing (measured at time 2).

  15. Comparing instrumental and deliberative paradigms underpinning the assessment of social values for cultural ecosystem services

    DEFF Research Database (Denmark)

    Raymond, Christopher M.; Kenter, Jasper O.; Plieninger, Tobias

    2014-01-01

    Despite rapid advancements in the development of non-monetary techniques for the assessment of social values for ecosystem services, little research attention has been devoted to the evaluation of their underpinning paradigms. This study evaluates two contrasting paradigms for the assessment...... of social values in non-monetary terms: an instrumental paradigm involving an objective assessment of the distribution, type and/or intensity of values that individuals assign to the current state of ecosystems and a deliberative paradigm involving the exploration of desired end states through group...... discussion. We present and then justify through case examples two approaches for assessing social values for ecosystem services using the instrumental paradigm and two approaches using the deliberative paradigm. Each approach makes different assumptions about: the underlying rationale for values assessment...

  16. Comorbid substance use disorder in schizophrenia: a selective overview of neurobiological and cognitive underpinnings.

    Science.gov (United States)

    Thoma, Patrizia; Daum, Irene

    2013-09-01

    Although individuals with schizophrenia show a lifetime prevalence of 50% for suffering from a comorbid substance use disorder, substance abuse usually represents an exclusion criterion for studies on schizophrenia. This implies that surprisingly little is known about a large group of patients who are particularly difficult to treat. The aim of the present work is to provide a brief and non-exhaustive overview of the current knowledgebase about neurobiological and cognitive underpinnings for dual diagnosis schizophrenia patients. Studies published within the last 20 years were considered using computerized search engines. The focus was on nicotine, caffeine, alcohol, cannabis and cocaine being among the most common substances of abuse. All drugs of abuse target dopaminergic, glutamatergic and GABAergic transmission which are also involved in the pathophysiology of schizophrenia. Current literature suggests that neurocognitive function might beless disrupted in substance-abusing compared to non-abusing schizophrenia patients, but in particular the neuroimaging database on this topic is sparse. Detrimental effects on brain structure and function were shown for patients for whom alcohol is the main substance of abuse. It is as yet unclear whether this finding might be an artifact of age differences of patient subgroups with different substance abuse patterns. More research is warranted on the specific neurocognitive underpinnings of schizophrenia patients abusing distinct psychoactive substances. Treatment programs might either benefit from preserved cognitive function as a resource or specifically target cognitive impairment in different subgroups of addicted schizophrenia patients. © 2013 The Authors. Psychiatry and Clinical Neurosciences © 2013 Japanese Society of Psychiatry and Neurology.

  17. The Safe and Effective Use of Shared Data Underpinned by Stakeholder Engagement and Evaluation Practice.

    Science.gov (United States)

    Georgiou, Andrew; Magrabi, Farah; Hypponen, Hannele; Wong, Zoie Shui-Yee; Nykänen, Pirkko; Scott, Philip J; Ammenwerth, Elske; Rigby, Michael

    2018-04-22

     The paper draws attention to: i) key considerations involving the confidentiality, privacy, and security of shared data; and ii) the requirements needed to build collaborative arrangements encompassing all stakeholders with the goal of ensuring safe, secure, and quality use of shared data.  A narrative review of existing research and policy approaches along with expert perspectives drawn from the International Medical Informatics Association (IMIA) Working Group on Technology Assessment and Quality Development in Health Care and the European Federation for Medical Informatics (EFMI) Working Group for Assessment of Health Information Systems.  The technological ability to merge, link, re-use, and exchange data has outpaced the establishment of policies, procedures, and processes to monitor the ethics and legality of shared use of data. Questions remain about how to guarantee the security of shared data, and how to establish and maintain public trust across large-scale shared data enterprises. This paper identifies the importance of data governance frameworks (incorporating engagement with all stakeholders) to underpin the management of the ethics and legality of shared data use. The paper also provides some key considerations for the establishment of national approaches and measures to monitor compliance with best practice. Data sharing endeavours can help to underpin new collaborative models of health care which provide shared information, engagement, and accountability amongst all stakeholders. We believe that commitment to rigorous evaluation and stakeholder engagement will be critical to delivering health data benefits and the establishment of collaborative models of health care into the future. Georg Thieme Verlag KG Stuttgart.

  18. Prognostic relevance of the interaction between short-term, metronome-paced heart rate variability, and inflammation: results from the population-based CARLA cohort study.

    Science.gov (United States)

    Medenwald, Daniel; Swenne, Cees A; Loppnow, Harald; Kors, Jan A; Pietzner, Diana; Tiller, Daniel; Thiery, Joachim; Nuding, Sebastian; Greiser, Karin H; Haerting, Johannes; Werdan, Karl; Kluttig, Alexander

    2017-01-01

    To determine the interaction between HRV and inflammation and their association with cardiovascular/all-cause mortality in the general population. Subjects of the CARLA study (n = 1671; 778 women, 893 men, 45-83 years of age) were observed for an average follow-up period of 8.8 years (226 deaths, 70 cardiovascular deaths). Heart rate variability parameters were calculated from 5-min segments of 20-min resting electrocardiograms. High-sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), and soluble tumour necrosis factor-alpha receptor type 1 (sTNF-R1) were measured as inflammation parameters. The HRV parameters determined included the standard deviation of normal-to-normal intervals (SDNN), the root-mean-square of successive normal-interval differences (RMSSD), the low- and high-frequency (HF) power, the ratio of both, and non-linear parameters [Poincaré plot (SD1, SD2, SD1/SD2), short-term detrended fluctuation analysis]. We estimated hazard ratios by using covariate-adjusted Cox regression for cardiovascular and all-cause mortality incorporating an interaction term of HRV/inflammation parameters. Relative excess risk due to interactions (RERIs) were computed. We found an interaction effect of sTNF-R1 with SDNN (RERI: 0.5; 99% confidence interval (CI): 0.1-1.0), and a weaker effect with RMSSD (RERI: 0.4; 99% CI: 0.0-0.9) and HF (RERI: 0.4; 99% CI: 0.0-0.9) with respect to cardiovascular mortality on an additive scale after covariate adjustment. Neither IL-6 nor hsCRP showed a significant interaction with the HRV parameters. A change in TNF-α levels or the autonomic nervous system influences the mortality risk through both entities simultaneously. Thus, TNF-α and HRV need to be considered when predicating mortality. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

  19. How does Calanus helgolandicus maintain its population in a variable environment? Analysis of a 25-year time series from the English Channel

    DEFF Research Database (Denmark)

    Maud, J.L.; Atkinson, A.; Hirst, Andrew G.

    2015-01-01

    . However this relationship was driven by inter-annual variability in female abundance and not that of egg production per female, which ranged only two-fold. Winter abundance of C. helgolandicus at L4 was much more variable than abundance in other seasons, and reflected conditions from the previous growing...

  20. Ethical underpinnings for the development of health literacy in schools: ethical premises ('why'), orientations ('what') and tone ('how').

    Science.gov (United States)

    Paakkari, Leena; George, Shanti

    2018-03-06

    Schools are seen as crucial environments to influence and develop the health literacy of new generations, but without sufficient reflection on the ethical underpinnings of intentions and interventions around health literacy. In contrast, we argue here that ethics are fundamental to all education. The article adopts a 'One world' approach that generalizes broadly across the so-called Global North and Global South. It also generalizes across various age groups among school pupils, advocating age appropriate application of the arguments advanced. Our analysis examines why health literacy should be promoted in schools and argues that the purpose should embrace the values of social justice and should not stop at individual and national cost benefit analysis. Discussion about the orientation of health literacy highlights meta-cognitive skills around critical thinking, self-awareness and citizenship rather than lists of practical skills. Finally, approaches to health literacy in classrooms are presented with an ethical tone that draws attention to the power relations responsible for health inequities and that does not assume that such power relations are the given framework for health literacy interventions and activities. These arguments are reinforced by urging that related debates address dynamic social realities such as international migration. We reiterate the need for ethical questions to be consciously and systematically addressed from early on, beginning with intentions to promote health literacy even before these intentions are translated into action, within the political space where education meets public health and health promotion. We underline again the context of fluidity and dynamism, as new challenges emerge within pedagogies and curricula, especially in response to changing populations in the society around.

  1. Phenotypic variability in unicellular organisms: from calcium signalling to social behaviour.

    Science.gov (United States)

    Vogel, David; Nicolis, Stamatios C; Perez-Escudero, Alfonso; Nanjundiah, Vidyanand; Sumpter, David J T; Dussutour, Audrey

    2015-11-22

    Historically, research has focused on the mean and often neglected the variance. However, variability in nature is observable at all scales: among cells within an individual, among individuals within a population and among populations within a species. A fundamental quest in biology now is to find the mechanisms that underlie variability. Here, we investigated behavioural variability in a unique unicellular organism, Physarum polycephalum. We combined experiments and models to show that variability in cell signalling contributes to major differences in behaviour underpinning some aspects of social interactions. First, following thousands of cells under various contexts, we identified distinct behavioural phenotypes: 'slow-regular-social', 'fast-regular-social' and 'fast-irregular-asocial'. Second, coupling chemical analysis and behavioural assays we found that calcium signalling is responsible for these behavioural phenotypes. Finally, we show that differences in signalling and behaviour led to alternative social strategies. Our results have considerable implications for our understanding of the emergence of variability in living organisms. © 2015 The Author(s).

  2. Systematic review of evidence underpinning non-pharmacological therapies in dementia.

    Science.gov (United States)

    Olley, Richard; Morales, Andrea

    2017-05-15

    underpin the use of these therapies. This report on a PRISMA systematic review of the available literature demonstrates that only two therapies have some evidence to underpin the use of these non-pharmaceutical therapies and that a significant research gap is exists. What are the implications for practitioners? The implications for practitioners is that significant research effort is required to determine the efficacy of many of the therapies that are currently deployed, and thus many of the therapies used lack an evidence base at this time.

  3. Variability in the contribution of different life stages to population growth as a key factor in the invasion success of Pinus strobus.

    Directory of Open Access Journals (Sweden)

    Zuzana Münzbergová

    Full Text Available Despite the increasing number of studies attempting to model population growth in various organisms, we still know relatively little about the population dynamics of long-lived species that reproduce only in the later stages of their life cycle, such as trees. Predictions of the dynamics of these species are, however, urgently needed for planning management actions when species are either endangered or invasive. In long-lived species, a single management intervention may have consequences for several decades, and detailed knowledge of long-term performance can therefore elucidate possible outcomes during the management planning phase.We studied the population dynamics of an invasive tree species, Pinus strobus, in three habitat types represented by their position along the elevation gradient occupied by the species. In agreement with previous studies on the population dynamics of long-lived perennials, our results show that the survival of the largest trees exhibits the highest elasticity in all of the studied habitats. In contrast, life table response experiments (LTRE analysis showed that different stages contribute the most to population growth rates in different habitats, with generative reproduction being more important in lower slopes and valley bottoms and survival being more important on rock tops and upper slopes.The results indicate that P. strobus exhibits different growth strategies in different habitats that result in similar population growth rates. We propose that this plasticity in growth strategies is a key factor in the invasion success of the white pine. In all of the investigated habitats, the population growth rates are above 1, indicating that the population of the species is still increasing and has the ability to spread and occupy a wide range of habitats.

  4. Interindividual variability in the prevalence of OPRM1 and CYP2B6 gene variations may identify drug-susceptible populations.

    Science.gov (United States)

    Bunten, H; Liang, W J; Pounder, D J; Seneviratne, C; Osselton, D

    2011-09-01

    Methadone is used worldwide for the treatment of heroin addiction; however, fatal poisonings are increasingly reported. The prevalence of CYP2B6 and μ-opioid receptor (OPRM1) gene variations were examined between a postmortem population where the deaths were associated with methadone and a live nondrug-using control population using Taqman™ SNP Genotyping assays. The CYP2B6*6 allele was higher in the postmortem population, but the difference was not significant (P = 0.92). The CYP2B6 T750C promoter variation was similar in frequency for both populations. Linkage between T750C and CYP2B6*6 was identified for both populations (P < 0.01). The prevalence of the OPRM1 A118G variation was significantly higher in the control population (P = 0.0046), which might indicate a protective mechanism against opioid toxicity. Individual susceptibility to methadone may be determined by screening for CYP2B6*6.

  5. Frontopolar cortical inefficiency may underpin reward and working memory dysfunction in bipolar disorder.

    Science.gov (United States)

    Jogia, Jigar; Dima, Danai; Kumari, Veena; Frangou, Sophia

    2012-12-01

    Emotional dysregulation in bipolar disorder is thought to arise from dysfunction within prefrontal cortical regions involved in cognitive control coupled with increased or aberrant activation within regions engaged in emotional processing. The aim of this study was to determine the common and distinct patterns of functional brain abnormalities during reward and working memory processing in patients with bipolar disorder. Participants were 36 euthymic bipolar disorder patients and 37 healthy comparison subjects matched for age, sex and IQ. Functional magnetic resonance imaging (fMRI) was conducted during the Iowa Gambling Task (IGT) and the n-back working memory task. During both tasks, patients with bipolar disorder demonstrated a pattern of inefficient engagement within the ventral frontopolar prefrontal cortex with evidence of segregation along the medial-lateral dimension for reward and working memory processing, respectively. Moreover, patients also showed greater activation in the anterior cingulate cortex during the Iowa Gambling Task and in the insula during the n-back task. Our data implicate ventral frontopolar dysfunction as a core abnormality underpinning bipolar disorder and confirm that overactivation in regions involved in emotional arousal is present even in tasks that do not typically engage emotional systems.

  6. Theoretical underpinnings of state institutionalisation of inclusion and struggles in collective health in Latin America.

    Science.gov (United States)

    Mahmood, Qamar; Muntaner, Carles

    2018-03-28

    Community participation as a strategy in health aims to increase the role of citizens in health decision-making which are contextualised within the institutions of democracy. Electoral representation as the dominant model of democracy globally is based on the elite theory of democracy that sees political decision-making a prerogative of political elites. Such political elitism is counter to the idea of democratic participation. Neoliberalism together with elitism in political sphere have worsened social inequities by undermining working class interests. Latin America has seen adverse consequences of these social inequities. In response, social movements representing collective struggles of organised citizens arose in the region. This paper explores the theoretical underpinnings of democratic participation in contemporary Latin American context at the nexus of emerging social movement activism and policy responses. The paper will use empirical examples to highlight how such democratic practices at the societal level evolved while demanding political inclusion. These societal democratic practices in Latin America are redefining democracy, which continues to be seen in the political sphere only. Health reforms promoting participatory democracy in several Latin American countries have demonstrated that establishing institutions and mechanisms of democratic participation facilitate collective participation by the organised citizenry in state affairs.

  7. What Representations and Computations Underpin the Contribution of the Hippocampus to Generalization and Inference?

    Directory of Open Access Journals (Sweden)

    Dharshan eKumaran

    2012-06-01

    Full Text Available Empirical research and theoretical accounts have traditionally emphasized the function of the hippocampus in episodic memory. Here we draw attention to the importance of the hippocampus to generalization, and focus on the neural representations and computations that might underpin its role in tasks such as the paired associate inference paradigm. We make a principal distinction between two different mechanisms by which the hippocampus may support generalization: an encoding-based mechanism that creates overlapping representations that capture higher-order relationships between different items (e.g. TCM – and a retrieval-based model (REMERGE that effectively computes these relationships at the point of retrieval, through a recurrent mechanism that allows the dynamic interaction of multiple pattern separated episodic codes. We also discuss what we refer to as transfer effects - a more abstract example of generalization that has also been linked to the function of the hippocampus. We consider how this phenomenon poses inherent challenges for models such as TCM and REMERGE, and outline the potential applicability of a separate class of models - hierarchical bayesian models (HBMs in this context. Our hope is that this article will provide a basic framework within which to consider the theoretical mechanisms underlying the role of the hippocampus in generalization, and at a minimum serve as a stimulus for future work addressing issues that go to the heart of the function of the hippocampus.

  8. Neural underpinnings of divergent production of rules in numerical analogical reasoning.

    Science.gov (United States)

    Wu, Xiaofei; Jung, Rex E; Zhang, Hao

    2016-05-01

    Creativity plays an important role in numerical problem solving. Although the neural underpinnings of creativity have been studied over decades, very little is known about neural mechanisms of the creative process that relates to numerical problem solving. In the present study, we employed a numerical analogical reasoning task with functional Magnetic Resonance Imaging (fMRI) to investigate the neural correlates of divergent production of rules in numerical analogical reasoning. Participants performed two tasks: a multiple solution analogical reasoning task and a single solution analogical reasoning task. Results revealed that divergent production of rules involves significant activations at Brodmann area (BA) 10 in the right middle frontal cortex, BA 40 in the left inferior parietal lobule, and BA 8 in the superior frontal cortex. The results suggest that right BA 10 and left BA 40 are involved in the generation of novel rules, and BA 8 is associated with the inhibition of initial rules in numerical analogical reasoning. The findings shed light on the neural mechanisms of creativity in numerical processing. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. An Exploratory Qualitative Exploration of the Personal Values Underpinning Taiwanese and Malaysians’ Wine Consumption Behaviors

    Directory of Open Access Journals (Sweden)

    Miranda Mirosa

    2016-01-01

    Full Text Available Augmented buying power of East Asian consumers has resulted in increased interest in these markets. Wine is a particularly promising sector to target as the number of East Asians choosing to drink wine rises. In order to serve these markets, companies must understand factors influencing consumers’ choices. The objective of this research was to understand how Taiwanese and Malaysian consumers’ personal values influenced their consumption decisions about wine. The means–end chain framework and associated semi-structured interview technique, value laddering, was used to elicit consumers’ preferred product attributes, the consequences of these attributes and the values that underpin these consequences. Data collection involved intercepting foreign travelers from Malaysia and Taiwan in New Zealand (20 Taiwanese and 20 Malaysian to partake in a wine choice interview. The resulting findings are exploratory in nature. Analysis revealed the most preferred wine attributes for Taiwanese were “Price” and “Sensory Aspects”—that these attributes were linked to consequences “Financial Considerations” and “Satisfy Senses”—which in turn were linked to personal values “Self Direction” and “Achievement”. For the Malaysian participants, the attribute “Sensory Aspects” of wine was most important, as was the value “Hedonism”. This study adds to literature related to beverage consumption decision making by exploring cultural aspects. It also offers suggestions for practitioners interested in targeting these consumers.

  10. Oscillatory phase dynamics in neural entrainment underpin illusory percepts of time.

    Science.gov (United States)

    Herrmann, Björn; Henry, Molly J; Grigutsch, Maren; Obleser, Jonas

    2013-10-02

    Neural oscillatory dynamics are a candidate mechanism to steer perception of time and temporal rate change. While oscillator models of time perception are strongly supported by behavioral evidence, a direct link to neural oscillations and oscillatory entrainment has not yet been provided. In addition, it has thus far remained unaddressed how context-induced illusory percepts of time are coded for in oscillator models of time perception. To investigate these questions, we used magnetoencephalography and examined the neural oscillatory dynamics that underpin pitch-induced illusory percepts of temporal rate change. Human participants listened to frequency-modulated sounds that varied over time in both modulation rate and pitch, and judged the direction of rate change (decrease vs increase). Our results demonstrate distinct neural mechanisms of rate perception: Modulation rate changes directly affected listeners' rate percept as well as the exact frequency of the neural oscillation. However, pitch-induced illusory rate changes were unrelated to the exact frequency of the neural responses. The rate change illusion was instead linked to changes in neural phase patterns, which allowed for single-trial decoding of percepts. That is, illusory underestimations or overestimations of perceived rate change were tightly coupled to increased intertrial phase coherence and changes in cerebro-acoustic phase lag. The results provide insight on how illusory percepts of time are coded for by neural oscillatory dynamics.

  11. Neural Underpinnings of Decision Strategy Selection: A Review and a Theoretical Model.

    Science.gov (United States)

    Wichary, Szymon; Smolen, Tomasz

    2016-01-01

    In multi-attribute choice, decision makers use decision strategies to arrive at the final choice. What are the neural mechanisms underlying decision strategy selection? The first goal of this paper is to provide a literature review on the neural underpinnings and cognitive models of decision strategy selection and thus set the stage for a neurocognitive model of this process. The second goal is to outline such a unifying, mechanistic model that can explain the impact of noncognitive factors (e.g., affect, stress) on strategy selection. To this end, we review the evidence for the factors influencing strategy selection, the neural basis of strategy use and the cognitive models of this process. We also present the Bottom-Up Model of Strategy Selection (BUMSS). The model assumes that the use of the rational Weighted Additive strategy and the boundedly rational heuristic Take The Best can be explained by one unifying, neurophysiologically plausible mechanism, based on the interaction of the frontoparietal network, orbitofrontal cortex, anterior cingulate cortex and the brainstem nucleus locus coeruleus. According to BUMSS, there are three processes that form the bottom-up mechanism of decision strategy selection and lead to the final choice: (1) cue weight computation, (2) gain modulation, and (3) weighted additive evaluation of alternatives. We discuss how these processes might be implemented in the brain, and how this knowledge allows us to formulate novel predictions linking strategy use and neural signals.

  12. Two Complementary Mechanisms Underpin Cell Wall Patterning during Xylem Vessel Development.

    Science.gov (United States)

    Schneider, Rene; Tang, Lu; Lampugnani, Edwin R; Barkwill, Sarah; Lathe, Rahul; Zhang, Yi; McFarlane, Heather E; Pesquet, Edouard; Niittyla, Totte; Mansfield, Shawn D; Zhou, Yihua; Persson, Staffan

    2017-10-01

    The evolution of the plant vasculature was essential for the emergence of terrestrial life. Xylem vessels are solute-transporting elements in the vasculature that possess secondary wall thickenings deposited in intricate patterns. Evenly dispersed microtubule (MT) bands support the formation of these wall thickenings, but how the MTs direct cell wall synthesis during this process remains largely unknown. Cellulose is the major secondary wall constituent and is synthesized by plasma membrane-localized cellulose synthases (CesAs) whose catalytic activity propels them through the membrane. We show that the protein CELLULOSE SYNTHASE INTERACTING1 (CSI1)/POM2 is necessary to align the secondary wall CesAs and MTs during the initial phase of xylem vessel development in Arabidopsis thaliana and rice ( Oryza sativa ). Surprisingly, these MT-driven patterns successively become imprinted and sufficient to sustain the continued progression of wall thickening in the absence of MTs and CSI1/POM2 function. Hence, two complementary principles underpin wall patterning during xylem vessel development. © 2017 American Society of Plant Biologists. All rights reserved.

  13. An Ontology-Underpinned Emergency Response System for Water Pollution Accidents

    Directory of Open Access Journals (Sweden)

    Xiaoliang Meng

    2018-02-01

    Full Text Available With the unceasing development and maturation of environment geographic information system, the response to water pollution accidents has been digitalized through the combination of monitoring sensors, management servers, and application software. However, most of these systems only achieve the basic and general geospatial data management and functional process tasks by adopting mechanistic water-quality models. To satisfy the sustainable monitoring and real-time emergency response application demand of the government and public users, it is a hotspot to study how to make the water pollution information being semantic and make the referred applications intelligent. Thus, the architecture of the ontology-underpinned emergency response system for water pollution accidents is proposed in this paper. This paper also makes a case study for usability testing of the water ontology models, and emergency response rules through an online water pollution emergency response system. The system contributes scientifically to the safety and sustainability of drinking water by providing emergency response and decision-making to the government and public in a timely manner.

  14. Neural computations underpinning the strategic management of influence in advice giving.

    Science.gov (United States)

    Hertz, Uri; Palminteri, Stefano; Brunetti, Silvia; Olesen, Cecilie; Frith, Chris D; Bahrami, Bahador

    2017-12-19

    Research on social influence has focused mainly on the target of influence (e.g., consumer and voter); thus, the cognitive and neurobiological underpinnings of the source of the influence (e.g., politicians and salesmen) remain unknown. Here, in a three-sided advice-giving game, two advisers competed to influence a client by modulating their own confidence in their advice about which lottery the client should choose. We report that advisers' strategy depends on their level of influence on the client and their merit relative to one another. Moreover, blood-oxygenation-level-dependent (BOLD) signal in the temporo-parietal junction is modulated by adviser's current level of influence on the client, and relative merit prediction error affects activity in medial-prefrontal cortex. Both types of social information modulate ventral striatum response. By demonstrating what happens in our mind and brain when we try to influence others, these results begin to explain the biological mechanisms that shape inter-individual differences in social conduct.

  15. Cognitive control in adolescence: neural underpinnings and relation to self-report behaviors.

    Directory of Open Access Journals (Sweden)

    Jessica R Andrews-Hanna

    Full Text Available Adolescence is commonly characterized by impulsivity, poor decision-making, and lack of foresight. However, the developmental neural underpinnings of these characteristics are not well established.To test the hypothesis that these adolescent behaviors are linked to under-developed proactive control mechanisms, the present study employed a hybrid block/event-related functional Magnetic Resonance Imaging (fMRI Stroop paradigm combined with self-report questionnaires in a large sample of adolescents and adults, ranging in age from 14 to 25. Compared to adults, adolescents under-activated a set of brain regions implicated in proactive top-down control across task blocks comprised of difficult and easy trials. Moreover, the magnitude of lateral prefrontal activity in adolescents predicted self-report measures of impulse control, foresight, and resistance to peer pressure. Consistent with reactive compensatory mechanisms to reduced proactive control, older adolescents exhibited elevated transient activity in regions implicated in response-related interference resolution.Collectively, these results suggest that maturation of cognitive control may be partly mediated by earlier development of neural systems supporting reactive control and delayed development of systems supporting proactive control. Importantly, the development of these mechanisms is associated with cognitive control in real-life behaviors.

  16. Neural Underpinnings of Decision Strategy Selection: A Review and a Theoretical Model

    Science.gov (United States)

    Wichary, Szymon; Smolen, Tomasz

    2016-01-01

    In multi-attribute choice, decision makers use decision strategies to arrive at the final choice. What are the neural mechanisms underlying decision strategy selection? The first goal of this paper is to provide a literature review on the neural underpinnings and cognitive models of decision strategy selection and thus set the stage for a neurocognitive model of this process. The second goal is to outline such a unifying, mechanistic model that can explain the impact of noncognitive factors (e.g., affect, stress) on strategy selection. To this end, we review the evidence for the factors influencing strategy selection, the neural basis of strategy use and the cognitive models of this process. We also present the Bottom-Up Model of Strategy Selection (BUMSS). The model assumes that the use of the rational Weighted Additive strategy and the boundedly rational heuristic Take The Best can be explained by one unifying, neurophysiologically plausible mechanism, based on the interaction of the frontoparietal network, orbitofrontal cortex, anterior cingulate cortex and the brainstem nucleus locus coeruleus. According to BUMSS, there are three processes that form the bottom-up mechanism of decision strategy selection and lead to the final choice: (1) cue weight computation, (2) gain modulation, and (3) weighted additive evaluation of alternatives. We discuss how these processes might be implemented in the brain, and how this knowledge allows us to formulate novel predictions linking strategy use and neural signals. PMID:27877103

  17. Neural underpinnings of decision strategy selection: a review and a theoretical model

    Directory of Open Access Journals (Sweden)

    Szymon Wichary

    2016-11-01

    Full Text Available In multi-attribute choice, decision makers use various decision strategies to arrive at the final choice. What are the neural mechanisms underlying decision strategy selection? The first goal of this paper is to provide a literature review on the neural underpinnings and cognitive models of decision strategy selection and thus set the stage for a unifying neurocognitive model of this process. The second goal is to outline such a unifying, mechanistic model that can explain the impact of noncognitive factors (e.g. affect, stress on strategy selection. To this end, we review the evidence for the factors influencing strategy selection, the neural basis of strategy use and the cognitive models explaining this process. We also present the neurocognitive Bottom-Up Model of Strategy Selection (BUMSS. The model assumes that the use of the rational, normative Weighted Additive strategy and the boundedly rational heuristic Take The Best can be explained by one unifying, neurophysiologically plausible mechanism, based on the interaction of the frontoparietal network, orbitofrontal cortex, anterior cingulate cortex and the brainstem nucleus locus coeruleus. According to BUMSS, there are three processes that form the bottom-up mechanism of decision strategy selection and lead to the final choice: 1 cue weight computation, 2 gain modulation, and 3 weighted additive evaluation of alternatives. We discuss how these processes might be implemented in the brain, and how this knowledge allows us to formulate novel predictions linking strategy use and neurophysiological indices.

  18. Associative learning mechanisms underpinning the transition from recreational drug use to addiction.

    Science.gov (United States)

    Hogarth, Lee; Balleine, Bernard W; Corbit, Laura H; Killcross, Simon

    2013-04-01

    Learning theory proposes that drug seeking is a synthesis of multiple controllers. Whereas goal-directed drug seeking is determined by the anticipated incentive value of the drug, habitual drug seeking is elicited by stimuli that have formed a direct association with the response. Moreover, drug-paired stimuli can transfer control over separately trained drug seeking responses by retrieving an expectation of the drug's identity (specific transfer) or incentive value (general transfer). This review covers outcome devaluation and transfer of stimulus-control procedures in humans and animals, which isolate the differential governance of drug seeking by these four controllers following various degrees of contingent and noncontingent drug exposure. The neural mechanisms underpinning these four controllers are also reviewed. These studies suggest that although initial drug seeking is goal-directed, chronic drug exposure confers a progressive loss of control over action selection by specific outcome representations (impaired outcome devaluation and specific transfer), and a concomitant increase in control over action selection by antecedent stimuli (enhanced habit and general transfer). The prefrontal cortex and mediodorsal thalamus may play a role in this drug-induced transition to behavioral autonomy. © 2012 New York Academy of Sciences.

  19. A concept for a magnetic field detector underpinned by the nonlinear dynamics of coupled multiferroic devices

    Science.gov (United States)

    Beninato, A.; Emery, T.; Baglio, S.; Andò, B.; Bulsara, A. R.; Jenkins, C.; Palkar, V.

    2013-12-01

    Multiferroic (MF) composites, in which magnetic and ferroelectric orders coexist, represent a very attractive class of materials with promising applications in areas, such as spintronics, memories, and sensors. One of the most important multiferroics is the perovskite phase of bismuth ferrite, which exhibits weak magnetoelectric properties at room temperature; its properties can be enhanced by doping with other elements such as dysprosium. A recent paper has demonstrated that a thin film of Bi0.7Dy0.3FeO3 shows good magnetoelectric coupling. In separate work it has been shown that a carefully crafted ring connection of N (N odd and N ≥ 3) ferroelectric capacitors yields, past a critical point, nonlinear oscillations that can be exploited for electric (E) field sensing. These two results represent the starting point of our work. In this paper the (electrical) hysteresis, experimentally measured in the MF material Bi0.7Dy0.3FeO3, is characterized with the applied magnetic field (B) taken as a control parameter. This yields a "blueprint" for a magnetic (B) field sensor: a ring-oscillator coupling of N = 3 Sawyer-Tower circuits each underpinned by a mutliferroic element. In this configuration, the changes induced in the ferroelectric behavior by the external or "target" B-field are quantified, thus providing a pathway for very low power and high sensitivity B-field sensing.

  20. Storytelling: A Qualitative Tool to Promote Health Among Vulnerable Populations.

    Science.gov (United States)

    Palacios, Janelle F; Salem, Benissa; Hodge, Felicia Schanche; Albarrán, Cyndi R; Anaebere, Ann; Hayes-Bautista, Teodocia Maria

    2015-09-01

    Storytelling is a basic cultural phenomenon that has recently been recognized as a valuable method for collecting research data and developing multidisciplinary interventions. The purpose of this article is to present a collection of nursing scholarship wherein the concept of storytelling, underpinned by cultural phenomena, is explored for data collection and intervention. A conceptual analysis of storytelling reveals key variables. Following a brief review of current research focused on storytelling used within health care, three case studies among three vulnerable populations (American Indian teen mothers, American Indian cancer survivors, and African American women at risk for HIV/AIDS) demonstrate the uses of storytelling for data collection and intervention. Implications for transcultural nursing regarding storytelling are discussed. © The Author(s) 2014.

  1. Reader strategies: variability and error- methodology, findings, and health policy implications from a study of the U.S. population of mammographers

    Science.gov (United States)

    Beam, Craig A.

    2002-04-01

    Each year, approximately 60% of all US women over the age of 40 utilize mammography. Through the matrix of an imaging technology, this Population of Patients (POP) interacts with a population of approximately 20,000 physicians who interpret mammograms in the US. This latter Population of Diagnosticians (POD) operationally serves as the interface between an image-centric healthcare technology system and patient. Methods: using data collected from a large POD and POP based study, I evaluate the distribution of several ROC curve-related parameters in the POD and explore the health policy implications of a population ROC curve for mammography. Results and Conclusions: Principal Components Analysis suggests that two Binormal parameters are sufficient to explain variation in the POD and implies that the Binormal model is foundational to Health Policy Research in Mammography. A population ROC curve based on percentiles of the POD can be used to set targets to achieve national health policy goals. Medical Image Perception science provides the framework. Alternatively, a restrictive policy can be envisioned using performance criteria based on area. However, the data suggests this sort of policy would be too costly in terms of reduced healthcare service capacity in the US in the face of burgeoning demands.

  2. Host differentiation and variability of Orobanche crenata populations from legume species in Morocco as revealed by cross-infestation and molecular analysis.

    Science.gov (United States)

    Ennami, Mounia; Briache, Fatima Zahra; Gaboun, Fatima; Abdelwahd, Rabha; Ghaouti, Lamiae; Belqadi, Loubna; Westwood, James; Mentag, Rachid

    2017-08-01

    Orobanche crenata represents a major biotic constraint to production of faba bean and lentil in Morocco. While this parasitic plant attacks both of these crops, the extent to which Orobanche biotypes specialise in parasitising specific crops is unknown. To address this question, we studied O. crenata that grew on different hosts and quantified their host specificity to faba bean and lentil. The virulence of O. crenata populations on each host was investigated through field trials, pot and Petri dishes assays. Genetic diversity of the parasite populations was also assessed through molecular analyses. The two legume species showed distinct patterns of specificity. Faba bean was more susceptible to both O. crenata populations, while the specificity for lentil by lentil-grown O. crenata was evident at the final stage of the parasite life cycle as shown by correspondence factorial analyses. Considerable internal variation (81%) within O. crenata populations parasitising both legume species was observed by molecular analyses, but significant divergence (19%; Ø = 0.189; P = 0.010) among the populations was detected. These results indicate that O. crenata can adapt to specific host species, which is important knowledge when developing integrated pest management practices for parasitic weed control. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  3. Root biomass production in populations of six rooted macrophytes in response to Cu exposure: intra-specific variability versus constitutive-like tolerance.

    Science.gov (United States)

    Marchand, L; Nsanganwimana, F; Lamy, J B; Quintela-Sabaris, C; Gonnelli, C; Colzi, I; Fletcher, T; Oustrière, N; Kolbas, A; Kidd, P; Bordas, F; Newell, P; Alvarenga, P; Deletic, A; Mench, M

    2014-10-01

    Intra-specific variability of root biomass production (RP) of six rooted macrophytes, i.e. Juncus effusus, Phragmites australis, Schoenoplectus lacustris, Typha latifolia, Phalaris arundinacea, and Iris pseudacorus grown from clones, in response to Cu exposure was investigated. Root biomass production varied widely for all these macrophytes in control conditions (0.08 μM) according to the sampling site. Root biomass production of T. latifolia and I. pseudacorus in the 2.5-25 μM Cu range depended on the sampling location but not on the Cu dose in the growth medium. For P. australis, J. effusus, S. lacustris, and P. arundinacea, an intra-specific variability of RP depending on both the sampling location and the Cu-dose was evidenced. This intra-specific variability of RP depending on the sampling location and of Cu-tolerance for these last four species suggests that Cu constitutive tolerance for all rooted macrophytes is not a species-wide trait but it exhibits variability for some species. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Chains of (dis)trust : Exploring the underpinnings of knowledge-sharing and quality care across mental health services

    NARCIS (Netherlands)

    Brown, P.R.; Calnan, M.W.

    Quality and safety in healthcare settings are underpinned by organisational cultures, which facilitate or impede the refinement, sharing and application of knowledge. Avoiding the use of the term culture as a residual category, we focus specifically on describing chains of (dis)trust, analysing

  5. On the inference of agency in operant action : an examination of the cognitive and neural underpinnings in health and schizophrenia

    NARCIS (Netherlands)

    Renes, R.A.

    2016-01-01

    This dissertation elucidates cognitive and neural underpinnings of the sense of agency, which is the feeling that we are in control of our actions and the subsequent consequences. This consciously accessible sensation of control is pervasive, sometimes subtle, and can even be illusory in nature.

  6. Empirical evaluation of the conceptual model underpinning a regional aquatic long-term monitoring program using causal modelling

    Science.gov (United States)

    Irvine, Kathryn M.; Miller, Scott; Al-Chokhachy, Robert K.; Archer, Erik; Roper, Brett B.; Kershner, Jeffrey L.

    2015-01-01

    Conceptual models are an integral facet of long-term monitoring programs. Proposed linkages between drivers, stressors, and ecological indicators are identified within the conceptual model of most mandated programs. We empirically evaluate a conceptual model developed for a regional aquatic and riparian monitoring program using causal models (i.e., Bayesian path analysis). We assess whether data gathered for regional status and trend estimation can also provide insights on why a stream may deviate from reference conditions. We target the hypothesized causal pathways for how anthropogenic drivers of road density, percent grazing, and percent forest within a catchment affect instream biological condition. We found instream temperature and fine sediments in arid sites and only fine sediments in mesic sites accounted for a significant portion of the maximum possible variation explainable in biological condition among managed sites. However, the biological significance of the direct effects of anthropogenic drivers on instream temperature and fine sediments were minimal or not detected. Consequently, there was weak to no biological support for causal pathways related to anthropogenic drivers’ impact on biological condition. With weak biological and statistical effect sizes, ignoring environmental contextual variables and covariates that explain natural heterogeneity would have resulted in no evidence of human impacts on biological integrity in some instances. For programs targeting the effects of anthropogenic activities, it is imperative to identify both land use practices and mechanisms that have led to degraded conditions (i.e., moving beyond simple status and trend estimation). Our empirical evaluation of the conceptual model underpinning the long-term monitoring program provided an opportunity for learning and, consequently, we discuss survey design elements that require modification to achieve question driven monitoring, a necessary step in the practice of

  7. Relationships between greenhouse gas emissions and cultivable bacterial populations in conventional, organic and long-term grass plots as affected by environmental variables and disturbances

    NARCIS (Netherlands)

    Bruggen, van A.H.C.; He, M.; Zelenev, V.V.; Semenov, V.M.; Semenov, A.M.; Kuznetsova, T.V.; Khodzaeva, Anna K.; Kuznetsov, A.M.; Semenov, M.V.

    2017-01-01

    Daily dynamics of greenhouse gas (GHG) emissions and cultivable bacterial populations have rarely been examined. The objectives were: (1) to investigate if dynamics of GHG emissions can be described by harmonics and are related to those of cultivable bacteria after soil disturbances in three

  8. Population Genetics and Genetic Variability ofBulinus globosus (Gastropoda: Planorbidae) From the Two Main River Systems in Zimbabwe

    DEFF Research Database (Denmark)

    Mukaratirwa, S.; Siegismund, Hans Redlef; Kristensen, Thomas K.

    1996-01-01

    screened eight loci were resolved, and six of them were polymorphic in at least one of the populations sampled. Genotypic distributions showed deviations from Hardy-Weinberg proportions due to deficiency of heterozygotes and this was attributed to selfing. The Save River drainage system, which falls under...

  9. Digital games for type 1 and type 2 diabetes: underpinning theory with three illustrative examples.

    Science.gov (United States)

    Kamel Boulos, Maged N; Gammon, Shauna; Dixon, Mavis C; MacRury, Sandra M; Fergusson, Michael J; Miranda Rodrigues, Francisco; Mourinho Baptista, Telmo; Yang, Stephen P

    2015-03-18

    Digital games are an important class of eHealth interventions in diabetes, made possible by the Internet and a good range of affordable mobile devices (eg, mobile phones and tablets) available to consumers these days. Gamifying disease management can help children, adolescents, and adults with diabetes to better cope with their lifelong condition. Gamification and social in-game components are used to motivate players/patients and positively change their behavior and lifestyle. In this paper, we start by presenting the main challenges facing people with diabetes-children/adolescents and adults-from a clinical perspective, followed by three short illustrative examples of mobile and desktop game apps and platforms designed by Ayogo Health, Inc. (Vancouver, BC, Canada) for type 1 diabetes (one example) and type 2 diabetes (two examples). The games target different age groups with different needs-children with type 1 diabetes versus adults with type 2 diabetes. The paper is not meant to be an exhaustive review of all digital game offerings available for people with type 1 and type 2 diabetes, but rather to serve as a taster of a few of the game genres on offer today for both types of diabetes, with a brief discussion of (1) some of the underpinning psychological mechanisms of gamified digital interventions and platforms as self-management adherence tools, and more, in diabetes, and (2) some of the hypothesized potential benefits that might be gained from their routine use by people with diabetes. More research evidence from full-scale evaluation studies is needed and expected in the near future that will quantify, qualify, and establish the evidence base concerning this gamification potential, such as what works in each age group/patient type, what does not, and under which settings and criteria.

  10. Neural underpinnings of distortions in the experience of time across senses

    Directory of Open Access Journals (Sweden)

    Deborah L. Harrington

    2011-07-01

    Full Text Available Auditory signals (A are perceived as lasting longer than visual signals (V of the same physical duration when they are compared together. Despite considerable debate about how this illusion arises psychologically, the neural underpinnings have not been studied. We used functional magnetic resonance imaging (fMRI to investigate the neural bases of audiovisual temporal distortions and more generally, intersensory timing. Adults underwent fMRI while judging the relative duration of successively presented standard interval (SI-comparison interval (CI pairs, which were unimodal (A-A, V-V or crossmodal (V-A, A-V. Mechanisms of time dilation and compression were identified by comparing the two crossmodal pairs. Mechanisms of intersensory timing were identified by comparing the unimodal and crossmodal conditions. The behavioral results showed that auditory CIs were perceived as lasting longer than visual CIs. There were three novel fMRI results. First, time dilation and compression were distinguished by differential activation of higher sensory areas (superior temporal, posterior insula, middle occipital, which typically showed stronger effective connectivity when time was dilated (V-A. Second, when time was compressed (A-V activation was greater in frontal cognitive-control centers, which guide decision making. These areas did not exhibit effective connectivity. Third, intrasensory timing was distinguished from intersensory timing partly by decreased striatal and increased superior parietal activation. These regions showed stronger connectivity with visual, memory, and cognitive-control centers during intersensory timing. Altogether, the results indicate that time dilation and compression arise from the connectivity strength of higher sensory systems with other areas. Conversely, more extensive network interactions are needed with core timing (striatum and attention (superior parietal centers to integrate time codes for intersensory signals.

  11. Digital Games for Type 1 and Type 2 Diabetes: Underpinning Theory With Three Illustrative Examples

    Science.gov (United States)

    Gammon, Shauna; Dixon, Mavis C; MacRury, Sandra M; Fergusson, Michael J; Miranda Rodrigues, Francisco; Mourinho Baptista, Telmo; Yang, Stephen P

    2015-01-01

    Digital games are an important class of eHealth interventions in diabetes, made possible by the Internet and a good range of affordable mobile devices (eg, mobile phones and tablets) available to consumers these days. Gamifying disease management can help children, adolescents, and adults with diabetes to better cope with their lifelong condition. Gamification and social in-game components are used to motivate players/patients and positively change their behavior and lifestyle. In this paper, we start by presenting the main challenges facing people with diabetes—children/adolescents and adults—from a clinical perspective, followed by three short illustrative examples of mobile and desktop game apps and platforms designed by Ayogo Health, Inc. (Vancouver, BC, Canada) for type 1 diabetes (one example) and type 2 diabetes (two examples). The games target different age groups with different needs—children with type 1 diabetes versus adults with type 2 diabetes. The paper is not meant to be an exhaustive review of all digital game offerings available for people with type 1 and type 2 diabetes, but rather to serve as a taster of a few of the game genres on offer today for both types of diabetes, with a brief discussion of (1) some of the underpinning psychological mechanisms of gamified digital interventions and platforms as self-management adherence tools, and more, in diabetes, and (2) some of the hypothesized potential benefits that might be gained from their routine use by people with diabetes. More research evidence from full-scale evaluation studies is needed and expected in the near future that will quantify, qualify, and establish the evidence base concerning this gamification potential, such as what works in each age group/patient type, what does not, and under which settings and criteria. PMID:25791276

  12. Lung eQTLs to help reveal the molecular underpinnings of asthma.

    Directory of Open Access Journals (Sweden)

    Ke Hao

    Full Text Available Genome-wide association studies (GWAS have identified loci reproducibly associated with pulmonary diseases; however, the molecular mechanism underlying these associations are largely unknown. The objectives of this study were to discover genetic variants affecting gene expression in human lung tissue, to refine susceptibility loci for asthma identified in GWAS studies, and to use the genetics of gene expression and network analyses to find key molecular drivers of asthma. We performed a genome-wide search for expression quantitative trait loci (eQTL in 1,111 human lung samples. The lung eQTL dataset was then used to inform asthma genetic studies reported in the literature. The top ranked lung eQTLs were integrated with the GWAS on asthma reported by the GABRIEL consortium to generate a Bayesian gene expression network for discovery of novel molecular pathways underpinning asthma. We detected 17,178 cis- and 593 trans- lung eQTLs, which can be used to explore the functional consequences of loci associated with lung diseases and traits. Some strong eQTLs are also asthma susceptibility loci. For example, rs3859192 on chr17q21 is robustly associated with the mRNA levels of GSDMA (P = 3.55 × 10(-151. The genetic-gene expression network identified the SOCS3 pathway as one of the key drivers of asthma. The eQTLs and gene networks identified in this study are powerful tools for elucidating the causal mechanisms underlying pulmonary disease. This data resource offers much-needed support to pinpoint the causal genes and characterize the molecular function of gene variants associated with lung diseases.

  13. [Self-regulation and virtual reality in forensic psychiatry: An emphasis on theoretical underpinnings].

    Science.gov (United States)

    Benbouriche, M; Renaud, P; Pelletier, J-F; De Loor, P

    2016-12-01

    Forensic psychiatry is the field whose expertise is the assessment and treatment of offending behaviours, in particular when offenses are related to mental illness. An underlying question for all etiological models concerns the manner in which an individual's behaviours are organized. Specifically, it becomes crucial to understand how certain individuals come to display maladaptive behaviours in a given environment, especially when considering issues such as offenders' responsibility and their ability to change their behaviours. Thanks to its ability to generate specific environments, associated with a high experimental control on generated simulations, virtual reality is gaining recognition in forensic psychiatry. Virtual reality has generated promising research data and may turn out to be a remarkable clinical tool in the near future. While research has increased, a conceptual work about its theoretical underpinnings is still lacking. However, no important benefit should be expected from the introduction of a new tool (as innovative as virtual reality) without an explicit and heuristic theoretical framework capable of clarifying its benefits in forensic psychiatry. Our paper introduces self-regulation perspective as the most suitable theoretical framework for virtual reality in forensic psychiatry. It will be argued that virtual reality does not solely help to increase ecological validity. However, it does allow one to grant access to an improved understanding of violent offending behaviours by probing into the underlying mechanisms involved in the self-regulation of behaviours in a dynamical environment. Illustrations are given as well as a discussion regarding perspectives in the use of virtual reality in forensic psychiatry. Copyright © 2015 L’Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.

  14. Partial diel migration: A facultative migration underpinned by long-term inter-individual variation.

    Science.gov (United States)

    Harrison, Philip M; Gutowsky, Lee F G; Martins, Eduardo G; Patterson, David A; Cooke, Steven J; Power, Michael

    2017-09-01

    The variations in migration that comprise partial diel migrations, putatively occur entirely as a consequence of behavioural flexibility. However, seasonal partial migrations are increasingly recognised to be mediated by a combination of reversible plasticity in response to environmental variation and individual variation due to genetic and environmental effects. Here, we test the hypothesis that while partial diel migration heterogeneity occurs primarily due to short-term within-individual flexibility in behaviour, long-term individual differences in migratory behaviour also underpin this migration variation. Specifically, we use a hierarchical behavioural reaction norm approach to partition within- and among-individual variation in depth use and diel plasticity in depth use, across short- and long-term time-scales, in a group of 47 burbot (Lota lota) tagged with depth-sensing acoustic telemetry transmitters. We found that within-individual variation at the among-dates-within-seasons and among-seasons scale, explained the dominant proportion of phenotypic variation. However, individuals also repeatedly differed in their expression of migration behaviour over the 2 year study duration. These results reveal that diel migration variation occurs primarily due to short-term within-individual flexibility in depth use and diel migration behaviour. However, repeatable individual differences also played a key role in mediating partial diel migration. These findings represent a significant advancement of our understanding of the mechanisms generating the important, yet poorly understood phenomena of partial diel migration. Moreover, given the pervasive occurrence of diel migrations across aquatic taxa, these findings indicate that individual differences have an important, yet previously unacknowledged role in structuring the temporal and vertical dynamics of aquatic ecosystems. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

  15. Visual strategies underpinning the development of visual-motor expertise when hitting a ball.

    Science.gov (United States)

    Sarpeshkar, Vishnu; Abernethy, Bruce; Mann, David L

    2017-10-01

    It is well known that skilled batters in fast-ball sports do not align their gaze with the ball throughout ball-flight, but instead adopt a unique sequence of eye and head movements that contribute toward their skill. However, much of what we know about visual-motor behavior in hitting is based on studies that have employed case study designs, and/or used simplified tasks that fall short of replicating the spatiotemporal demands experienced in the natural environment. The aim of this study was to provide a comprehensive examination of the eye and head movement strategies that underpin the development of visual-motor expertise when intercepting a fast-moving target. Eye and head movements were examined in situ for 4 groups of cricket batters, who were crossed for playing level (elite or club) and age (U19 or adult), when hitting balls that followed either straight or curving ('swinging') trajectories. The results provide support for some widely cited markers of expertise in batting, while questioning the legitimacy of others. Swinging trajectories alter the visual-motor behavior of all batters, though in large part because of the uncertainty generated by the possibility of a variation in trajectory rather than any actual change in trajectory per se. Moreover, curving trajectories influence visual-motor behavior in a nonlinear fashion, with targets that curve away from the observer influencing behavior more than those that curve inward. The findings provide a more comprehensive understanding of the development of visual-motor expertise in interception. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  16. The importance of professional skills alongside scientific and technical excellence to underpin ethical geoscience practice

    Science.gov (United States)

    Allington, Ruth; Fernandez-Fuentes, Isabel

    2013-04-01

    There is consensus that reliable ground models, based on a sound understanding of the geology and surface processes are vital as a basis for natural hazard identification and risk assessment, and there is a great deal of skill and experience in the geoscience community with mapping, modelling and predicting natural hazards and their likely impacts. This presentation will highlight the contributions of geology and geomorphology in the identification of natural hazards and mitigation of their impacts. It will then consider a range of "professional skills" that are needed by geoscientists working with other specialists and non-specialists (e.g. engineers, emergency services, land-use planners, architects responsible for building codes, politicians, regulators, the public etc) alongside technical and scientific excellence. It will argue that development and application of both scientific/technical and professional skills is essential to ensure that the maps, models and other data relevant to natural hazards and environmental change are used to provide effective public protection through communication, land-use planning and planning for resilience. The professional skills of particular importance include interdisciplinary collaboration; project management; cost-benefit analysis; effective communication with specialists and non specialists (especially the public); and facilitative skills. All the technical, scientific and professional skills need to be applied competently and with the highest standards of ethical underpinning. The contribution will consider how this can be achieved (or at least facilitated) through professional training, award of professional titles, licensure etc, drawing on international examples of best practice in professional codes of conduct and regulation directed to the protection of the public.

  17. Matrix expansion and syncytial aggregation of syndecan-1+ cells underpin villous atrophy in coeliac disease.

    Directory of Open Access Journals (Sweden)

    Camilla Salvestrini

    Full Text Available We studied the expression of sulphated glycosaminoglycans (GAGs in coeliac disease (CD mucosa, as they are critical determinants of tissue volume, which increases in active disease. We also examined mucosal expression of IL-6, which stimulates excess GAG synthesis in disorders such as Grave's ophthalmopathy.We stained archival jejunal biopsies from 5 children with CD at diagnosis, on gluten-free diet and challenge for sulphated GAGs. We then examined duodenal biopsies from 9 children with CD compared to 9 histological normal controls, staining for sulphated GAGs, heparan sulphate proteoglycans (HSPG, short-chain HSPG (Δ-HSPG and the proteoglycan syndecan-1 (CD138, which is expressed on epithelium and plasma cells. We confirmed findings with a second monoclonal in another 12 coeliac children. We determined mucosal IL-6 expression by immunohistochemistry and PCR in 9 further cases and controls, and used quantitative real time PCR for other Th17 pathway cytokines in an additional 10 cases and controls.In CD, HSPG expression was lost in the epithelial compartment but contrastingly maintained within an expanded lamina propria. Within the upper lamina propria, clusters of syndecan-1(+ plasma cells formed extensive syncytial sheets, comprising adherent plasma cells, lysed cells with punctate cytoplasmic staining and shed syndecan ectodomains. A dense infiltrate of IL-6(+ mononuclear cells was detected in active coeliac disease, also localised to the upper lamina propria, with significantly increased mRNA expression of IL-6 and IL-17A but not IL-23 p19.Matrix expansion, through syndecan-1(+ cell recruitment and lamina propria GAG increase, underpins villous atrophy in coeliac disease. The syndecan-1(+ cell syncytia and excess GAG production recapitulate elements of the invertebrate encapsulation reaction, itself dependent on insect transglutaminase and glutaminated early response proteins. As in other matrix expansion disorders, IL-6 is upregulated and

  18. Matrix Expansion and Syncytial Aggregation of Syndecan-1+ Cells Underpin Villous Atrophy in Coeliac Disease

    Science.gov (United States)

    Salvestrini, Camilla; Lucas, Mark; Lionetti, Paolo; Torrente, Franco; James, Sean; Phillips, Alan D.; Murch, Simon H.

    2014-01-01

    Background We studied the expression of sulphated glycosaminoglycans (GAGs) in coeliac disease (CD) mucosa, as they are critical determinants of tissue volume, which increases in active disease. We also examined mucosal expression of IL-6, which stimulates excess GAG synthesis in disorders such as Grave's ophthalmopathy. Methods We stained archival jejunal biopsies from 5 children with CD at diagnosis, on gluten-free diet and challenge for sulphated GAGs. We then examined duodenal biopsies from 9 children with CD compared to 9 histological normal controls, staining for sulphated GAGs, heparan sulphate proteoglycans (HSPG), short-chain HSPG (Δ-HSPG) and the proteoglycan syndecan-1 (CD138), which is expressed on epithelium and plasma cells. We confirmed findings with a second monoclonal in another 12 coeliac children. We determined mucosal IL-6 expression by immunohistochemistry and PCR in 9 further cases and controls, and used quantitative real time PCR for other Th17 pathway cytokines in an additional 10 cases and controls. Results In CD, HSPG expression was lost in the epithelial compartment but contrastingly maintained within an expanded lamina propria. Within the upper lamina propria, clusters of syndecan-1+ plasma cells formed extensive syncytial sheets, comprising adherent plasma cells, lysed cells with punctate cytoplasmic staining and shed syndecan ectodomains. A dense infiltrate of IL-6+ mononuclear cells was detected in active coeliac disease, also localised to the upper lamina propria, with significantly increased mRNA expression of IL-6 and IL-17A but not IL-23 p19. Conclusions Matrix expansion, through syndecan-1+ cell recruitment and lamina propria GAG increase, underpins villous atrophy in coeliac disease. The syndecan-1+ cell syncytia and excess GAG production recapitulate elements of the invertebrate encapsulation reaction, itself dependent on insect transglutaminase and glutaminated early response proteins. As in other matrix expansion disorders

  19. Variability of cutaneous and nasal population levels between patients colonized and infected by multidrug-resistant bacteria in two Brazilian intensive care units.

    Science.gov (United States)

    Damaceno, Quésia; Nicoli, Jacques R; Oliveira, Adriana

    2015-01-01

    To compare cutaneous and nasal population levels between patients colonized and infected by multidrug-resistant organisms in two intensive care units. A prospective cohort study was performed in adult intensive care units of two hospitals in Belo Horizonte, Brazil (April 2012 to February 2013). Clinical and demographic data were first collected by reviewing patients' charts. Then, samples collected with nasal, groin, and perineum swabs were cultivated in selective media for 48 h at 37°C. After isolation, determination of antimicrobial susceptibility and biochemical identification were performed. A total of 53 cases of colonization were observed by the following bacteria in decreasing frequencies: imipenem-resistant Acinetobacter baumannii (50.9%), vancomycin-resistant Enterococcus faecalis (43.4%), extended-spectrum beta-lactamase-producing Klebsiella pneumoniae (37.7%), imipenem-resistant Pseudomonas aeruginosa (32.1%), oxacillin-resistant Staphylococcus aureus (7.5%), and imipenem-resistant Klebsiella pneumoniae (5.7%). Among these colonization cases, 26 (49.0%) were followed by infection with bacteria phenotypically similar to those of the colonization. A relation between high population levels of colonization by most of the multidrug-resistant organisms at anatomical sites and a subsequent infection was observed. After colonization/infection, bacterial population levels decreased progressively and spontaneously until disappearance by day 45 in all the anatomical sites and for all the multidrug-resistant organisms. There was a correlation between high population levels of colonization by multidrug-resistant organisms at anatomical sites and a subsequent infection. Reduction in multidrug-resistant organism populations after colonization at anatomical sites could be a preventive measure to reduce evolution to infection as well as transmission of these bacteria between patients in intensive care unit.

  20. Distribution of the Most Common Genetic Variants Associated with a Variable Drug Response in the Population of the Republic of Macedonia

    Directory of Open Access Journals (Sweden)

    Nestorovska Kapedanovska A.

    2014-12-01

    Full Text Available Genetic variation in the regulation, expression and activity of genes coding for Phase I, Phase II drug metabolizing enzymes (DMEs and drug targets, can be defining factors for the variability in both the effectiveness and occurrence of drug therapy side effects. Information regarding the geographic structure and multi-ethnic distribution of clinically relevant genetic variations is becoming increasingly useful for improving drug therapy and explaining inter-individual and inter-ethnic differences in drug response.

  1. Espesor corneal y variables epidemiológicas y fisiológicas en población de riesgo de glaucoma Corneal thickness and the epidemiological and physiological variables seen in the glaucoma risk population

    Directory of Open Access Journals (Sweden)

    Idalia Triana Casado

    2012-12-01

    Full Text Available Objetivo: caracterizar el espesor corneal central en pacientes con factores de riesgo de glaucoma crónico simple. Métodos: se realizó un estudio epidemiológico, observacional, descriptivo y longitudinal prospectivo, en el Servicio de Glaucoma del Hospital "Dr. Salvador Allende" durante el año 2010. El universo estuvo constituido por 1 238 pacientes que acudieron a la consulta de oftalmología por síntomas astenópicos. La muestra, aplicados los criterios de inclusión y exclusión, quedó conformada por 656 pacientes con factores de riesgo de la enfermedad, de estos se desecharon 19 por una diferencia entre los ojos de 10 µm o más de espesor corneal. Las variables analizadas fueron: espesor corneal, edad, sexo, color de la piel y presión intraocular. Resultados: de los pacientes con factores de riesgo de glaucoma, predominaron aquellos entre 50 y 59 años de edad (22,76 %, masculinos (60,28 % y de piel no blanca (57,29 %. El espesor corneal estuvo disminuido (61,85 % y la presión intraocular aumentada (55,41 %, aún con ajuste (46,93 %. Conclusiones: la disminución del espesor corneal estuvo relacionada con la edad, el sexo femenino, la piel no blanca y el aumento de la presión intraocular en aquellos pacientes sospechosos de glaucoma.Objective: to characterize the central corneal thickness seen in patients with simple chronic glaucoma risk factors. Methods: a prospective longitudinal, descriptive, observational, and epidemiological study was conducted in the Glaucoma Service of “Dr. Salvador Allende” hospital during 2010. The universe of study was made up of 1 238 patients that went to the ophthalmological service due to asthenopic symptoms. Taking the inclusion and exclusion criteria into account, the final sample was composed by 656 patients with glaucoma risk factors, 19 of whom were excluded because of 10 µm and over difference in the corneal thickness between the eyes. The analyzed variables were corneal thickness, age

  2. Free and Open Source Software underpinning the European Forest Data Centre

    Science.gov (United States)

    Rodriguez Aseretto, Dario; Di Leo, Margherita; de Rigo, Daniele; Corti, Paolo; McInerney, Daniel; Camia, Andrea; San-Miguel-Ayanz, Jesús

    2013-04-01

    Worldwide, governments are growingly focusing [1] on free and open source software (FOSS) as a move toward transparency and the freedom to run, copy, study, change and improve the software [2]. The European Commission (EC) is also supporting the development of FOSS (see e.g., [3]). In addition to the financial savings, FOSS contributes to scientific knowledge freedom in computational science (CS) [4] and is increasingly rewarded in the science-policy interface within the emerging paradigm of open science [5-8]. Since complex computational science applications may be affected by software uncertainty [4,9-11], FOSS may help to mitigate part of the impact of software errors by CS community-driven open review, correction and evolution of scientific code [10,12-15]. The continental scale of EC science-based policy support implies wide networks of scientific collaboration. Thematic information systems also may benefit from this approach within reproducible [16] integrated modelling [4]. This is supported by the EC strategy on FOSS: "for the development of new information systems, where deployment is foreseen by parties outside of the EC infrastructure, [F]OSS will be the preferred choice and in any case used whenever possible" [17]. The aim of this contribution is to highlight how a continental scale information system may exploit and integrate FOSS technologies within the transdisciplinary research underpinning such a complex system. A European example is discussed where FOSS innervates both the structure of the information system itself and the inherent transdisciplinary research for modelling the data and information which constitute the system content. The information system. The European Forest Data Centre (EFDAC, http://forest.jrc.ec.europa.eu/efdac/) has been established at the EC Joint Research Centre (JRC) as the focal point for forest data and information in Europe to supply European decision-makers with processed, quality checked and timely policy relevant

  3. Genetic variability of HLA in the Dariusleut Hutterites. A comparative genetic analysis of the Hutterities, the Amish, and other selected Caucasian populations.

    OpenAIRE

    Morgan, K; Holmes, T M; Schlaut, J; Marchuk, L; Kovithavongs, T; Pazderka, F; Dossetor, J B

    1980-01-01

    There are three endogamous subdivisions of the Hutterite population, a North American religious isolate. These individuals live on communal farms, and residence is strictly patrilocal. We report on the distributions of HLA-A and B alleles and haplotypes in 203 married women from one subdivision--the Dariusleut--in Alberta, Canada. We demonstrate that there is significant linkage disequilbrium among a large fraction of the distinct haplotypes in the Dariusleut Hutterite data; there is a restri...

  4. Variable effects of prevalence correction of population denominators on differentials in myocardial infarction incidence: a record linkage study in Aboriginal and non-Aboriginal Western Australians.

    Science.gov (United States)

    Katzenellenbogen, Judith M; Sanfilippo, Frank M; Hobbs, Michael S T; Briffa, Tom G; Ridout, Steve C; Knuiman, Matthew W; Dimer, Lyn; Taylor, Kate P; Thompson, Peter L; Thompson, Sandra C

    2011-06-01

    To investigate the impact of prevalence correction of population denominators on myocardial infarction (MI) incidence rates, rate ratios, and rate differences in Aboriginal vs. non-Aboriginal Western Australians aged 25-74 years during the study period 2000-2004. Person-based linked hospital and mortality data sets were used to estimate the number of prevalent and first-ever MI cases each year from 2000 to 2004 using a 15-year look-back period. Age-specific and -standardized MI incidence rates were calculated using both prevalence-corrected and -uncorrected population denominators, by sex and Aboriginality. The impact of prevalence correction on rates increased with age, was higher for men than women, and substantially greater for Aboriginal than non-Aboriginal people. Despite the systematic underestimation of incidence, prevalence correction had little impact on the Aboriginal to non-Aboriginal age-standardized rate ratios (6% and 4% underestimate in men and women, respectively), although the impact on rate differences was more marked (12% and 6%, respectively). The percentage underestimate of differentials was greater at older ages. Prevalence correction of denominators, while more accurate, is difficult to apply and may add modestly to the quantification of relative disparities in MI incidence between populations. Absolute incidence disparities using uncorrected denominators may have an error >10%. Copyright © 2011 Elsevier Inc. All rights reserved.

  5. Knowledge and Concern about STIs/HIV and Sociodemographic Variables Associated with Getting Tested for HIV Among the General Population in Spain.

    Science.gov (United States)

    Teva, Inmaculada; de Araújo, Ludgleydson Fernandes; de la Paz Bermúdez, María

    2018-07-04

    HIV testing is important in terms of prevention and treatment. However, HIV testing rates in the Spanish general population remains low. Therefore, HIV testing promotion constitutes a key issue. A high level of knowledge about HIV/AIDS is associated with having been tested for HIV. The general aim of this study was to determine the prevalence of people who had ever been tested for HIV in Spain. The sample consisted of 1,106 participants from the general population - 60.0% females and 40.0% males - aged between 17 and 55 years old. The assessment instruments were a questionnaire on sociodemographic data and HIV testing, a scale of knowledge about STIs and HIV/AIDS, and a scale of concern about STIs/HIV. Results showed that greater knowledge about STIs and HIV was associated with a greater likelihood of being tested for HIV (OR = .77; 95.0% CI = .73-.82; p concern about HIV/AIDS decreased the likelihood of not having been tested for HIV (OR = .87; 95.0% CI = .83-.92; p concern about STIs was, the lower their likelihood of not having been tested for HIV was (OR = .87; 95.0% CI = .83-.91; p < .05). It is necessary to promote HIV testing in the general population as well as to consider their socio-demographic and psychological characteristics.

  6. Full likelihood analysis of genetic risk with variable age at onset disease--combining population-based registry data and demographic information.

    Directory of Open Access Journals (Sweden)

    Janne Pitkäniemi

    Full Text Available BACKGROUND: In genetic studies of rare complex diseases it is common to ascertain familial data from population based registries through all incident cases diagnosed during a pre-defined enrollment period. Such an ascertainment procedure is typically taken into account in the statistical analysis of the familial data by constructing either a retrospective or prospective likelihood expression, which conditions on the ascertainment event. Both of these approaches lead to a substantial loss of valuable data. METHODOLOGY AND FINDINGS: Here we consider instead the possibilities provided by a Bayesian approach to risk analysis, which also incorporates the ascertainment procedure and reference information concerning the genetic composition of the target population to the considered statistical model. Furthermore, the proposed Bayesian hierarchical survival model does not require the considered genotype or haplotype effects be expressed as functions of corresponding allelic effects. Our modeling strategy is illustrated by a risk analysis of type 1 diabetes mellitus (T1D in the Finnish population-based on the HLA-A, HLA-B and DRB1 human leucocyte antigen (HLA information available for both ascertained sibships and a large number of unrelated individuals from the Finnish bone marrow donor registry. The heterozygous genotype DR3/DR4 at the DRB1 locus was associated with the lowest predictive probability of T1D free survival to the age of 15, the estimate being 0.936 (0.926; 0.945 95% credible interval compared to the average population T1D free survival probability of 0.995. SIGNIFICANCE: The proposed statistical method can be modified to other population-based family data ascertained from a disease registry provided that the ascertainment process is well documented, and that external information concerning the sizes of birth cohorts and a suitable reference sample are available. We confirm the earlier findings from the same data concerning the HLA-DR3

  7. Variabilidad genética de poblaciones en cautiverio de Crocodylus moreletii (Crocodylia: Crocodylidae mediante el uso de marcadores microsatelitales Genetic variability in captive populations of Crocodylus moreletii (Crocodylia: Crocodylidae using microsatellites markers

    Directory of Open Access Journals (Sweden)

    Ricardo Serna-Lagunes

    2012-03-01

    Full Text Available Crocodylus moreletii representa un emblema para los ecosistemas tropicales de México pero actualmente está amenazada por extinción. Sorprendentemente, hay una falta de información de su constitución genética, que debe ser evaluada para un manejo apropiado ex situ y para toma de decisiones en la liberación de cocodrilos a su hábitat natural. El objetivo del estudio fue caracterizar y comparar la variabilidad genética de cuatro grupos poblacionales de C. moreletii (dos silvestres y dos nacidas ex situ. Mediante PCR se amplificaron siete loci de microsatélites polimórficos, sin embargo se encontró déficit de heterocigotos en las poblaciones (promedio H O=0.02 mermado por la presencia de alelos nulos. El AMOVA indicó que la mayor proporción de variabilidad genética se encuentra dentro de las poblaciones y una limitada diferenciación genética entre poblaciones (promedio F ST =0.03, probablemente debida al alto índice de endogamia (promedio F IS=0.97. Al comparar la variabilidad genética inter e intra especies de cocodrilianos, encontramos que en C. moreletii está muy por debajo de los reportados. Se concluye que la limitada variabilidad genética de las poblaciones nacidas ex situ probablemente se debe al efecto fundador derivado de la estructura social de sus progenitores, y de las poblaciones silvestres, por el efecto cuello de botella, inferido por el limitado tamaño efectivo de población que presentó históricamente en su distribución natural.Genetic variability in captive populations of Crocodylus moreletii (Crocodylia: Crocodylidae using microsatellites markers. Crocodylus moreletii, an extinction threatened species, represents an emblem for tropical ecosystems in Mexico. Surprisingly, there is a lack of information about their genetic constitution, which should be evaluated for a proper management ex situ and for making decisions on the release of crocodiles into natural habitats. The aim of this study was to

  8. Genetic Variability, Genotype × Environment Interaction, Correlation, and GGE Biplot Analysis for Grain Iron and Zinc Concentration and Other Agronomic Traits in RIL Population of Sorghum (Sorghum bicolor L. Moench

    Directory of Open Access Journals (Sweden)

    Rahul M. Phuke

    2017-05-01

    Full Text Available The low grain iron and zinc densities are well documented problems in food crops, affecting crop nutritional quality especially in cereals. Sorghum is a major source of energy and micronutrients for majority of population in Africa and central India. Understanding genetic variation, genotype × environment interaction and association between these traits is critical for development of improved cultivars with high iron and zinc. A total of 336 sorghum RILs (Recombinant Inbred Lines were evaluated for grain iron and zinc concentration along with other agronomic traits for 2 years at three locations. The results showed that large variability exists in RIL population for both micronutrients (Iron = 10.8 to 76.4 mg kg−1 and Zinc = 10.2 to 58.7 mg kg−1, across environments and agronomic traits. Genotype × environment interaction for both micronutrients (iron and zinc was highly significant. GGE biplots comparison for grain iron and zinc showed greater variation across environments. The results also showed that G × E was substantial for grain iron and zinc, hence wider testing needed for taking care of G × E interaction to breed micronutrient rich sorghum lines. Iron and zinc concentration showed high significant positive correlation (across environment = 0.79; p < 0.01 indicating possibility of simultaneous effective selection for both the traits. The RIL population showed good variability and high heritabilities (>0.60, in individual environments for Fe and Zn and other traits studied indicating its suitability to map QTL for iron and zinc.

  9. Resource diversity and provenance underpin spatial patterns in functional diversity across native and exotic species.

    Science.gov (United States)

    Méndez, Verónica; Wood, Jamie R; Butler, Simon J

    2018-05-01

    Functional diversity metrics are increasingly used to augment or replace taxonomic diversity metrics to deliver more mechanistic insights into community structure and function. Metrics used to describe landscape structure and characteristics share many of the same limitations as taxonomy-based metrics, particularly their reliance on anthropogenically defined typologies with little consideration of structure, management, or function. However, the development of alternative metrics to describe landscape characteristics has been limited. Here, we extend the functional diversity framework to characterize landscapes based on the diversity of resources available across habitats present. We then examine the influence of resource diversity and provenance on the functional diversities of native and exotic avian communities in New Zealand. Invasive species are increasingly prevalent and considered a global threat to ecosystem function, but the characteristics of and interactions between sympatric native and exotic communities remain unresolved. Understanding their comparative responses to environmental change and the mechanisms underpinning them is of growing importance in predicting community dynamics and changing ecosystem function. We use (i) matrices of resource use (species) and resource availability (habitats) and (ii) occurrence data for 62 native and 25 exotic species and 19 native and 13 exotic habitats in 2015 10 × 10 km quadrats to examine the relationship between native and exotic avian and landscape functional diversity. The numbers of species in, and functional diversities of, native and exotic communities were positively related. Each community displayed evidence of environmental filtering, but it was significantly stronger for exotic species. Less environmental filtering occurred in landscapes providing a more diverse combination of resources, with resource provenance also an influential factor. Landscape functional diversity explained a greater

  10. Elucidating the atomistic mechanisms underpinning plasticity in Li-Si nanostructures

    Science.gov (United States)

    Yan, Xin; Gouissem, Afif; Guduru, Pradeep R.; Sharma, Pradeep

    2017-10-01

    Amorphous lithium-silicon (a-Li-Si), especially in nanostructure form, is an attractive high-capacity anode material for next-generation Li-ion batteries. During cycles of charging and discharging, a-Li-Si undergoes substantive inelastic deformation and exhibits microcracking. The mechanical response to repeated lithiation-delithiation eventually results in the loss of electrical contact and consequent decrease of capacity, thus underscoring the importance of studying the plasticity of a-Li-Si nanostructures. In recent years, a variety of phenomenological continuum theories have been introduced that purport to model plasticity and the electro-chemo-mechanical behavior of a-Li-Si. Unfortunately, the micromechanisms and atomistic considerations underlying plasticity in Li-Si material are not yet fully understood and this impedes the development of physics-based constitutive models. Conventional molecular dynamics, although extensively used to study this material, is grossly inadequate to resolve this matter. As is well known, conventional molecular dynamics simulations can only address phenomena with characteristic time scales of (at most) a microsecond. Accordingly, in such simulations, the mechanical behavior is deduced under conditions of very high strain rates (usually, 108s-1 or even higher). This limitation severely impacts a realistic assessment of rate-dependent effects. In this work, we attempt to circumvent the time-scale bottleneck of conventional molecular dynamics and provide novel insights into the mechanisms underpinning plastic deformation of Li-Si nanostructures. We utilize an approach that allows imposition of slow strain rates and involves the employment of a new and recently developed potential energy surface sampling method—the so-called autonomous basin climbing—to identify the local minima in the potential energy surface. Combined with other techniques, such as nudged elastic band, kinetic Monte Carlo and transition state theory, we assess

  11. Snake population venomics and antivenomics of Bothrops atrox: Paedomorphism along its transamazonian dispersal and implications of geographic venom variability on snakebite management.

    Science.gov (United States)

    Calvete, Juan J; Sanz, Libia; Pérez, Alicia; Borges, Adolfo; Vargas, Alba M; Lomonte, Bruno; Angulo, Yamileth; Gutiérrez, José María; Chalkidis, Hipócrates M; Mourão, Rosa H V; Furtado, M Fatima D; Moura-Da-Silva, Ana M

    2011-04-01

    We describe two geographically differentiated venom phenotypes across the wide distribution range of Bothrops atrox, from the Colombian Magdalena Medio Valley through Puerto Ayacucho and El Paují, in the Venezuelan States of Amazonas and Orinoquia, respectively, and São Bento in the Brazilian State of Maranhão. Colombian and Venezuelan venoms show an ontogenetic toxin profile phenotype whereas Brazilian venoms exhibit paedomorphic phenotypes. Venoms from each of the 16 localities sampled contain both population-specific toxins and proteins shared by neighboring B. atrox populations. Mapping the molecular similarity between conspecific populations onto a physical map of B. atrox range provides clues for tracing dispersal routes that account for the current biogeographic distribution of the species. The proteomic pattern is consistent with a model of southeast and southwest dispersal and allopatric fragmentation northern of the Amazon Basin, and trans-Amazonian expansion through the Andean Corridor and across the Amazon river between Monte Alegre and Santarém. An antivenomic approach applied to assess the efficacy towards B. atrox venoms of two antivenoms raised in Costa Rica and Brazil using Bothrops venoms different than B. atrox in the immunization mixtures showed that both antivenoms immunodepleted very efficiently the major toxins (PIII-SVMPs, serine proteinases, CRISP, LAO) of paedomorphic venoms from Puerto Ayacucho (Venezuelan Amazonia) through São Bento, but had impaired reactivity towards PLA(2) and P-I SVMP molecules abundantly present in ontogenetic venoms. The degree of immunodepletion achieved suggests that each of these antivenoms may be effective against envenomations by paedomorphic, and some ontogenetic, B. atrox venoms. Copyright © 2010 Elsevier B.V. All rights reserved.

  12. Plant population processes in the course of forest succession in abandoned meadows. I. Variability and diversity of floristic compositions, and biological mechanisms of species turnover

    OpenAIRE

    Krystyna Falińska

    2014-01-01

    Within Białowieża Forest the studies on the rate and nature of changes in meadow vegetation on the sites no longer mown were conducted for 15 years (1974-1988). The successional processes were analysed at various organizational levels by applying hierarchi­cal system of study areas, varying in size (Figs. 1, 2). Changes in plant landscape were studied on 15 ha, those in phytocoenoses - 4 × 1 ha, populations - 24 × 200 ml, and those in the individual development - 6 × 25 m2. Forest re-colonize...

  13. Characterizing uncertainty and population variability in the toxicokinetics of trichloroethylene and metabolites in mice, rats, and humans using an updated database, physiologically based pharmacokinetic (PBPK) model, and Bayesian approach

    International Nuclear Information System (INIS)

    Chiu, Weihsueh A.; Okino, Miles S.; Evans, Marina V.

    2009-01-01

    We have developed a comprehensive, Bayesian, PBPK model-based analysis of the population toxicokinetics of trichloroethylene (TCE) and its metabolites in mice, rats, and humans, considering a wider range of physiological, chemical, in vitro, and in vivo data than any previously published analysis of TCE. The toxicokinetics of the 'population average,' its population variability, and their uncertainties are characterized in an approach that strives to be maximally transparent and objective. Estimates of experimental variability and uncertainty were also included in this analysis. The experimental database was expanded to include virtually all available in vivo toxicokinetic data, which permitted, in rats and humans, the specification of separate datasets for model calibration and evaluation. The total combination of these approaches and PBPK analysis provides substantial support for the model predictions. In addition, we feel confident that the approach employed also yields an accurate characterization of the uncertainty in metabolic pathways for which available data were sparse or relatively indirect, such as GSH conjugation and respiratory tract metabolism. Key conclusions from the model predictions include the following: (1) as expected, TCE is substantially metabolized, primarily by oxidation at doses below saturation; (2) GSH conjugation and subsequent bioactivation in humans appear to be 10- to 100-fold greater than previously estimated; and (3) mice had the greatest rate of respiratory tract oxidative metabolism as compared to rats and humans. In a situation such as TCE in which there is large database of studies coupled with complex toxicokinetics, the Bayesian approach provides a systematic method of simultaneously estimating model parameters and characterizing their uncertainty and variability. However, care needs to be taken in its implementation to ensure biological consistency, transparency, and objectivity.

  14. Variability of albumin in blood serum as a possible reflection of evolutional influence of diluvial horses on population of native mountain horse in Serbia

    Directory of Open Access Journals (Sweden)

    Trailović Ružica

    2013-01-01

    Full Text Available Native mountain horse is an autochthonous ungulata with a domicile extending to the whole mountaneous region of Serbia, south of the Sava and Danube rivers. Along with native horses of other Balkan countries it is classified as Mediterranean pony, but unlike Balkan horses such as Skiros, Pinea, Pindos, Karakachan, Bosnian mountineous horse etc., mountineous horses in Serbia neither have been morphologically described nor were of concern to the scientific community till the end of the twentieth century. Investigations of albumin polymorphism in blood serum of native mountain horse were taken within a comprehensive reserch on morphologic, physiologic and genetic structure of this autochtonous ungulata breed. On the basis of the results obtained by electrophoretic separation of albumine types in native mountaneous horse blood serum, there were determined four albumine phenotypes: AA, AB, BB and BI which are inherited by three autosomal alleles AlA, Alb, All . The appearance of All allele in native mountaneous horse population points out to diluvial forest horse impact on process of microevolution of autochtonous native mountaneous horse. Occidental- specific albumin isoforms presence indicate the necessity of thorough study of evolution position and historic influence of different ancestors, and especially occidental horses on native mountain horse population in Serbia.

  15. Prevalence study of cognitive impairment and its associated sociodemographic variables using mini-mental status examination among elderly population residing in field practice areas of a medical college

    Directory of Open Access Journals (Sweden)

    Rakesh M Patel

    2018-01-01

    Full Text Available Context: The world is aging rapidly through “demographic transition.” The aging leads to CI Refers as Cognitive Impairment (CI – a risk factor for dementia. A community-based cross-sectional study was conducted among the elderly aged ≥50 years. Objectives: The objective of the study is to estimate the prevalence of cognitive dysfunction among the elderly and to identify the associated sociodemographic variables. Settings and Design: This was a community-based cross-sectional study in rural and urban field areas of a medical college. Subjects and Methods: Participants aged ≥50 years were interviewed using a structured questionnaire and screened for cognitive dysfunction using Gujarati version of Mini-Mental Status Examination. A score of 23 out of 30 was taken as the cutoff. Written informed consent was obtained from participants. Statistical Analysis Used: Univariate and multivariate analyses were done using SPSS version 17 and Epi Info version 6 to identify significant variables. Results: Of 560 participants, 140 (25% had CI. Rural (27.6% and female (29.8% prevalence was higher than urban (18.5% and male (19.1% prevalence. On multivariate analysis, age ≥60 years (odds ratio [OR]: 2.98 and illiteracy (OR: 39.8 had significant positive association with outcome; being employed (OR: 0.18, living with spouse (OR: 0.07, and living with spouse and children (OR: 0.08 had significant negative association with outcome. Conclusions: CI – a precursor of dementia – has serious clinical and public health consequences. Awareness generation and capacity building of primary health-care workers and family caregivers are core control strategies.

  16. Variability Bugs:

    DEFF Research Database (Denmark)

    Melo, Jean

    . Although many researchers suggest that preprocessor-based variability amplifies maintenance problems, there is little to no hard evidence on how actually variability affects programs and programmers. Specifically, how does variability affect programmers during maintenance tasks (bug finding in particular......)? How much harder is it to debug a program as variability increases? How do developers debug programs with variability? In what ways does variability affect bugs? In this Ph.D. thesis, I set off to address such issues through different perspectives using empirical research (based on controlled...... experiments) in order to understand quantitatively and qualitatively the impact of variability on programmers at bug finding and on buggy programs. From the program (and bug) perspective, the results show that variability is ubiquitous. There appears to be no specific nature of variability bugs that could...

  17. Combination of a higher-tier flow-through system and population modeling to assess the effects of time-variable exposure of isoproturon on the green algae Desmodesmus subspicatus and Pseudokirchneriella subcapitata.

    Science.gov (United States)

    Weber, Denis; Schaefer, Dieter; Dorgerloh, Michael; Bruns, Eric; Goerlitz, Gerhard; Hammel, Klaus; Preuss, Thomas G; Ratte, Hans Toni

    2012-04-01

    A flow-through system was developed to investigate the effects of time-variable exposure of pesticides on algae. A recently developed algae population model was used for simulations supported and verified by laboratory experiments. Flow-through studies with Desmodesmus subspicatus and Pseudokirchneriella subcapitata under time-variable exposure to isoproturon were performed, in which the exposure patterns were based on the results of FOrum for Co-ordination of pesticide fate models and their USe (FOCUS) model calculations for typical exposure situations via runoff or drain flow. Different types of pulsed exposure events were realized, including a whole range of repeated pulsed and steep peaks as well as periods of constant exposure. Both species recovered quickly in terms of growth from short-term exposure and according to substance dissipation from the system. Even at a peak 10 times the maximum predicted environmental concentration of isoproturon, only transient effects occurred on algae populations. No modified sensitivity or reduced growth was observed after repeated exposure. Model predictions of algal growth in the flow-through tests agreed well with the experimental data. The experimental boundary conditions and the physiological properties of the algae were used as the only model input. No calibration or parameter fitting was necessary. The combination of the flow-through experiments with the algae population model was revealed to be a powerful tool for the assessment of pulsed exposure on algae. It allowed investigating the growth reduction and recovery potential of algae after complex exposure, which is not possible with standard laboratory experiments alone. The results of the combined approach confirm the beneficial use of population models as supporting tools in higher-tier risk assessments of pesticides. Copyright © 2012 SETAC.

  18. Population fluctuations of Pyrodinium bahamense and Ceratium furca (Dinophyceae in Laguna Grande, Puerto Rico, and environmental variables associated during a three-year period

    Directory of Open Access Journals (Sweden)

    Miguel P. Sastre

    2013-12-01

    Full Text Available Bioluminescent bays and lagoons are unique natural environments and popular tourist attractions. However, the bioluminescence in many of these water bodies has declined, principally due to anthropogenic activities. In the Caribbean, the bioluminescence in these bays and lagoons is mostly produced by the dinoflagellate Pyrodinium bahamense var. bahamense. Laguna Grande is one of the three year-round bioluminescent water bodies in Puerto Rico that are known to remain but P. bahamense var. bahamense density fluctuations have not been studied. In this study we describe water quality parameters and density fluctuations of the most common dinoflagellates in Laguna Grande, P. bahamense var. bahamense and Ceratium furca, over a three-year period. For this, three sampling stations were established in Laguna Grande from which water samples were collected in triplicate and analyzed for temperature, phosphates, nitrates, salinity, water transparency, fluorescence, and dinoflagellate densities, at the water surface and at 2m depth, from May 2003 to May 2006. The results showed a density fluctuation pattern for P. bahamense var. bahamense, where higher densities were observed mainly from April to September, and lower densities from October to February. Density fluctuations of C. furca were more erratic and a repetitive pattern was not observed. Densities of P. bahamense var. bahamense ranged from 0.48 to 90 978 cells/L and densities of C. furca ranged from 0 to 11 200 cells/L. The mean population density throughout the sampling period was significantly higher in P. bahamense var. bahamense (mean=18 958.5 cells/L than in C. furca (mean=2 601.9 cells/L. Population densities of P. bahamense var. bahamense were negatively correlated with C. furca densities during the first year of sampling; however, they were positively correlated during the third year. Non-significant differences between surface and 2m depth samples were observed for temperature

  19. Relevance of the ancestry for the variability of the Drug-Metabolizing Enzymes CYP2C9, CYP2C19 and CYP2D6 polymorphisms in a multiethnic Costa Rican population.

    Science.gov (United States)

    Céspedes-Garro, Carolina; Rodrigues-Soares, Fernanda; Jiménez-Arce, Gerardo; Naranjo, María-Eugenia G; Tarazona-Santos, Eduardo; Fariñas, Humberto; Barrantes, Ramiro; Llerena, Adrián

    2016-09-01

    CYP2C9, CYP2C19 and CYP2D6 metabolize around 40% of drugs and their genes vary across populations. The Costa Rican population has a trihybrid ancestry and its key geographic location turns it into a suitable scenario to evaluate interethnic differences across populations. This study aims to describe the diversity of CYP2C9, CYP2C19 and CYP2D6 polymorphisms in Costa Rican populations in the context of their ancestry. A total of 448 healthy individuals were included in the study: Bribri (n= 47), Cabécar (n= 27), Maleku (n= 16), Guaymí (n= 30), Huetar (n= 48), Chorotega (n= 41), Admixed/Mestizos from the Central Valley/Guanacaste (n= 189), and Afro-Caribbeans (n= 50) from Limón. CYP2C9 (alleles *2, *3, *6) and CYP2C19 (*2, *3, *4, *5, *17) genotypes were determined by Real-Time PCR. African, European and Native American ancestry were inferred using 87 ancestry informative markers. The frequency of the decreased activity allele CYP2C9*2 is lower in the self-reported Amerindian groups compared to the admixed population, and the highest frequencies of CYP2C19*2 (null activity) and the CYP2C19*17 (increased activity) were found in the self-reported Afro-Caribbean population. Moreover, a frequency of 0.7 % CYP2C9 gPMs in the Admixed population and a variable frequency of CYP2C19 gUMs (0.0-32.6 %, more prevalent in Afro-Caribbeans) in Costa Rican populations, was found. Finally, the following alleles were positively correlated with genomic African ancestry and negatively correlated with genomic Native American ancestry: CYP2D6*5 (null activity), CYP2D6*17 (decreased activity), CYP2D6*29 (decreased activity) and CYP2C19*17 (increased activity). No correlation for CYP2C9 polymorphisms and genomic ancestry was found. Further studies assessing the CYP2C9 and CYP2C19 sequence in these populations, preferentially by sequencing these genes, are warranted.

  20. Radiation Doses to Members of the U.S. Population from Ubiquitous Radionuclides in the Body: Part 3, Results, Variability, and Uncertainty

    International Nuclear Information System (INIS)

    Watson, David J.; Strom, Daniel J.

    2011-01-01

    This paper is part three of a three-part series investigating annual effective doses to residents of the United States from intakes of ubiquitous radionuclides, including radionuclides occurring naturally, radionuclides whose concentrations are technologically enhanced, and anthropogenic radionuclides. The radionuclides of interest are the 238 U series (14 nuclides), the actinium series (headed by 235 U; 11 nuclides), and the 232 Th series (11 nuclides); primordial radionuclides 87 Rb and 40 K; cosmogenic and fallout radionuclides 14 C and 3 H; and purely anthropogenic radionuclides 137 Cs- 137m Ba, 129 I and 90 Sr- 90 Y. This series of papers explicitly excludes intakes from inhaling 222 Rn, 220 Rn, and their short-lived decay products; it also excludes intakes of radionuclides in occupational and medical settings. Part one reviewed, summarized, characterized, and grouped all published and some unpublished data for U.S. residents on ubiquitous radionuclide concentrations in tissues and organs. Part two described the methods used to organize the data collected in part one and segregate it into the ages and genders defined by the study, imputed missing values from the existing data, apportioned activity in bone, and imputed activity in hollow organ contents and the remainder of the body. This paper estimates equivalent doses to target tissues from source regions and maps target tissues to lists of tissues with International Commission on Radiation Protection (ICRP) tissue-weighting factors or to surrogate tissue regions when there is no direct match. Effective doses, using ICRP tissue-weighting factors recommended in 1977, 1990, and 2007, are then calculated, and an upper bound of variability of the effective dose is estimated by calculating the average coefficients of variation (CV), assuming all variance is due to variability. Most of the data were for adult males, whose average annual effective dose is estimated to be 337 (micro)Sv y -1 (CV = 0.65, geometric mean

  1. Global grass (Poaceae) success underpinned by traits facilitating colonization, persistence and habitat transformation.

    Science.gov (United States)

    Linder, H P; Lehmann, Caroline E R; Archibald, Sally; Osborne, Colin P; Richardson, David M

    2018-05-01

    Poaceae (the grasses) is arguably the most successful plant family, in terms of its global occurrence in (almost) all ecosystems with angiosperms, its ecological dominance in many ecosystems, and high species richness. We suggest that the success of grasses is best understood in context of their capacity to colonize, persist, and transform environments (the "Viking syndrome"). This results from combining effective long-distance dispersal, efficacious establishment biology, ecological flexibility, resilience to disturbance and the capacity to modify environments by changing the nature of fire and mammalian herbivory. We identify a diverse set of functional traits linked to dispersal, establishment and competitive abilities. Enhanced long-distance dispersal is determined by anemochory, epizoochory and endozoochory and is facilitated via the spikelet (and especially the awned lemma) which functions as the dispersal unit. Establishment success could be a consequence of the precocious embryo and large starch reserves, which may underpin the extremely short generation times in grasses. Post-establishment genetic bottlenecks may be mitigated by wind pollination and the widespread occurrence of polyploidy, in combination with gametic self-incompatibility. The ecological competitiveness of grasses is corroborated by their dominance across the range of environmental extremes tolerated by angiosperms, facilitated by both C 3 and C 4 photosynthesis, well-developed frost tolerance in several clades, and a sympodial growth form that enabled the evolution of both annual and long-lived life forms. Finally, absence of investment in wood (except in bamboos), and the presence of persistent buds at or below ground level, provides tolerance of repeated defoliation (whether by fire, frost, drought or herbivores). Biotic modification of environments via feedbacks with herbivory or fire reinforce grass dominance leading to open ecosystems. Grasses can be both palatable and productive

  2. Influence of Adiposity-Related Genetic Markers in a Population of Saudi Arabians Where Other Variables Influencing Obesity May Be Reduced

    Directory of Open Access Journals (Sweden)

    Khalid K. Alharbi

    2014-01-01

    Full Text Available Large scale studies in Europeans have clearly identified common polymorphism affecting BMI and obesity. We undertook a genotype study to examine the impact of variants, known to influence obesity, in a sample from the Saudi Arabian population, notable for its profound combination of low mean physical activity indices and high energy intake. Anthropometry measures and genotypes were obtained for 367 Saudis, taken from King Saud University and Biomarker Screening Project in Riyadh (Riyadh Cohort. We observed large effect sizes with obesity for rs10767664 (BDNF (OR = 1.923, P=0.00072 and rs3751812 (FTO (OR = 1.523, P=0.016 in our sample and, using weighted genetic risk scores, we found strong evidence of a cumulative effect using 11 SNPs taken predominantly from loci principally affecting appetite (OR = 2.57, P=0.00092. We used conditional analyses to discern which of our three highly correlated FTO SNPs were responsible for the observed signal, although we were unable to determine with confidence which best marked the causal site. Our analysis indicates that markers located in loci known to influence fat mass through increased appetite affect obesity in Saudi Arabians to an extent possibly greater than in Europeans. Larger scale studies will be necessary to obtain a precise comparison.

  3. The Variability of Seed Viability and Seed Vigour of Mindi (Melia azedarachlinn. from Several Populations in The Community Forest of West Java

    Directory of Open Access Journals (Sweden)

    Yulianti Bramasto

    2016-12-01

    Full Text Available The procurement of good quality seeds for the development of mindi (Melia azedarach L. in the community forest is absolutely necessary. The purpose of this research is to investigate the diversity of the viability and seedling vigor of mindi from different populations with various treatments of dormancy breaking. The sample materials were mindi seeds that were collected from 6 locations (6 seed lots or seed sources which were located in the community forest of West Java. There are 10 treatments of dormancy breaking that were applied in this study. The experiment design was Randomized Complete Design (RAL. The breaking dormancy  was focused to the delignification of hard seed coat.  Results showed that the most effective dormancy breaking for mindi seed was soaking in consentrated Sulfuric Acid (H2SO4 as long as 30 to 45 minutes. The first count for germination of mindi was on the 16 day and the final count was on the 31 day.The average value of germination percentage (DB for all seed sources was 40 %, while the highest which is 60% was mindi from Sumedang seed source. The highest value of germination rate that is 6,543%/etmal was seed  from Sumedangand seed from Gambung was the lowest (1,400 %/etmal. Keywords : community forest, Melia azedarach L., variation, viability, vigor.

  4. Examining variability in parent feeding practices within a low-income, racially/ethnically diverse, and immigrant population using ecological momentary assessment.

    Science.gov (United States)

    Berge, Jerica M; Tate, Allan; Trofholz, Amanda; Loth, Katie; Miner, Michael; Crow, Scott; Neumark-Sztainer, Dianne

    2018-04-21

    Current measures of parent feeding practices are typically survey-based and assessed as static/unchanging characteristics, failing to account for fluctuations in these behaviors across time and context. The current study uses ecological momentary assessment to examine variability of, and predictors of, parent feeding practices within a low-income, racially/ethnically diverse, and immigrant sample. Children ages 5-7 years old and their parents (n = 150 dyads) from six racial/ethnic groups (n = 25 from each; Black/African American, Hispanic, Hmong, Native American, Somali, White) were recruited for this mixed-methods study through primary care clinics. Among parents who used restriction (49%) and pressure-to-eat (69%) feeding practices, these feeding practices were utilized about every other day. Contextual factors at the meal associated with parent feeding practices included: number of people at the meal, who prepared the meal, types of food served at meals (e.g., pre-prepared, homemade, fast food), meal setting (e.g., kitchen table, front room), and meal emotional atmosphere (p meat proteins, and refined grains (p < 0.05). There were some differences by race/ethnicity across findings (p < 0.01), with Hmong parents engaging in the highest levels of pressure-to-eat feeding practices. Parent feeding practices varied across the week, indicating feeding practices are more likely to be context-specific, or state-like than trait-like. There were some meal characteristics more strongly associated with engaging in restriction and pressure-to-eat feeding practices. Given that parent feeding practices appear to be state-like, future interventions and health care providers who work with parents and children may want to address contextual factors associated with parent feeding practices to decrease restriction and pressure-to-eat parent feeding practices. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. The effect of climate variability on urinary stone attacks: increased incidence associated with temperature over 18 °C: a population-based study.

    Science.gov (United States)

    Park, Hyoung Keun; Bae, Sang Rak; Kim, Satbyul E; Choi, Woo Suk; Paick, Sung Hyun; Ho, Kim; Kim, Hyeong Gon; Lho, Yong Soo

    2015-02-01

    The aim of this study was to evaluate the effect of seasonal variation and climate parameters on urinary tract stone attack and investigate whether stone attack is increased sharply at a specific point. Nationwide data of total urinary tract stone attack numbers per month between January 2006 and December 2010 were obtained from the Korean Health Insurance Review and Assessment Service. The effects of climatic factors on monthly urinary stone attack were assessed using auto-regressive integrated moving average (ARIMA) regression method. A total of 1,702,913 stone attack cases were identified. Mean monthly and monthly average daily urinary stone attack cases were 28,382 ± 2,760 and 933 ± 85, respectively. The stone attack showed seasonal trends of sharp incline in June, a peak plateau from July to September, and a sharp decline after September. The correlation analysis showed that ambient temperature (r = 0.557, p r = 0.513, p stone attack cases. However, after adjustment for trends and seasonality, ambient temperature was the only climate factor associated with the stone attack cases in ARIMA regression test (p = 0.04). Threshold temperature was estimated as 18.4 °C. Risk of urinary stone attack significantly increases 1.71% (1.02-2.41 %, 95% confidence intervals) with a 1 °C increase of ambient temperature above the threshold point. In conclusion, monthly urinary stone attack cases were changed according to seasonal variation. Among the climates variables, only temperature had consistent association with stone attack and when the temperature is over 18.4 °C, urinary stone attack would be increased sharply.

  6. Host behaviour and physiology underpin individual variation in avian influenza virus infection in migratory Bewick's swans

    NARCIS (Netherlands)

    Hoye, B.J.; Fouchier, R.A.M; Klaassen, M.R.J.

    2012-01-01

    Individual variation in infection modulates both the dynamics of pathogens and their impact on host populations. It is therefore crucial to identify differential patterns of infection and understand the mechanisms responsible. Yet our understanding of infection heterogeneity in wildlife is limited,

  7. Clinical characteristics and premorbid variables in childhood-onset schizophrenia: a descriptive study of twelve cases from a schizophrenia founder population.

    Science.gov (United States)

    Maydell, R J; van der Walt, C; Roos, J L; Scribante, L; Ladikos, A

    2009-05-01

    To analyze clinical and demographic data of childhood-onset (12 years and younger) schizophrenia patients collected for a genetic study in schizophrenia, undertaken nationally in South Africa, using multiple parameters. Patients with an onset of schizophrenia at 12 years or younger, were included. From the Diagnostic Interview for Genetic Studies (DIGS), patients' information and summary report data was tabulated and analyzed. Specific subgroups were further compared. This sub-population of 12 subjects was further compared with a group of the adult sample. Of the 12 patients recruited, prominent results were: male to female ratio of 1:1; all had insidious onset of psychosis; a third had all 3 multidimensional impairment (MDI) symptoms; all patients that received ADHD treatment had ADHD treatment failure; two thirds had milestone delay; 58% had birth complications; a third were predominantly bottle fed; 42% had family history of schizophrenia; a third had family history of other major psychiatric conditions; all patients had at least one non-psychotic deviant behaviour (NPDB); no patient used cannabis; all delusions were paranoid; 92% had school achievement difficulty and a third had treatment resistance. Gender comparison included: earlier onset of psychosis in females; all females had aggression versus a third of males; more females had school achievement difficulty than males; males had more treatment resistance. Patients with MDI, compared to the sample average had: earlier onset of non-psychotic deviant behaviour; lower school drop-out rate; less social difficulty and no treatment resistance. The results compare well to previous research on this topic. The new concepts introduced by the present study require further investigation.

  8. Longitudinal association of short-term, metronome-paced heart rate variability and echocardiographically assessed cardiac structure at a 4-year follow-up: results from the prospective, population-based CARLA cohort.

    Science.gov (United States)

    Medenwald, Daniel; Swenne, Cees A; Frantz, Stefan; Nuding, Sebastian; Kors, Jan A; Pietzner, Diana; Tiller, Daniel; Greiser, Karin H; Kluttig, Alexander; Haerting, Johannes

    2017-12-01

    To assess the value of cardiac structure/function in predicting heart rate variability (HRV) and the possibly predictive value of HRV on cardiac parameters. Baseline and 4-year follow-up data from the population-based CARLA cohort were used (790 men, 646 women, aged 45-83 years at baseline and 50-87 years at follow-up). Echocardiographic and HRV recordings were performed at baseline and at follow-up. Linear regression models with a quadratic term were used. Crude and covariate adjusted estimates were calculated. Missing values were imputed by means of multiple imputation. Heart rate variability measures taken into account consisted of linear time and frequency domain [standard deviation of normal-to-normal intervals (SDNN), high-frequency power (HF), low-frequency power (LF), LF/HF ratio] and non-linear measures [detrended fluctuation analysis (DFA1), SD1, SD2, SD1/SD2 ratio]. Echocardiographic parameters considered were ventricular mass index, diastolic interventricular septum thickness, left ventricular diastolic dimension, left atrial dimension systolic (LADS), and ejection fraction (Teichholz). A negative quadratic relation between baseline LADS and change in SDNN and HF was observed. The maximum HF and SDNN change (an increase of roughly 0.02%) was predicted at LADS of 3.72 and 3.57 cm, respectively, while the majority of subjects experienced a decrease in HRV. There was no association between further echocardiographic parameters and change in HRV, and there was no evidence of a predictive value of HRV in the prediction of changes in cardiac structure. In the general population, LADS predicts 4-year alteration in SDNN and HF non-linearly. Because of the novelty of the result, analyses should be replicated in other populations. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions please email: journals.permissions@oup.com.

  9. The cut-off values of anthropometric variables for predicting mild cognitive impairment in Malaysian older adults: a large population based cross-sectional study

    Directory of Open Access Journals (Sweden)

    Won H

    2017-02-01

    Full Text Available Huiloo Won,1 Zahara Abdul Manaf,2 Arimi Fitri Mat Ludin,3 Mohd Azahadi Omar,4 Rosdinom Razali,5 Suzana Shahar2 1Nutrition Program, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, 2Dietetics Program, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, 3Biomedical Science Program, School of Diagnostic and Applied Health Sciences, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, 4Centre for Burden of Disease Research, Institute for Public Health, Ministry of Health Malaysia, 5Department of Psychiatry, Faculty of Medicine, Hospital Canselor Tuanku Muhriz, University Kebangsaan Malaysia, Kuala Lumpur, Malaysia Purpose: Older adults are at risk of mild cognitive impairment (MCI, and simple anthropometric measurements can be used to screen for this condition. Thus, the aim of this study was to explore the cut-off values of body mass index (BMI and waist circumference (WC for predicting the risk of MCI in older Malaysian adults.Methods: A total of 2,240 Malaysian older adults aged ≥60 years were recruited using multistage random sampling in a population based cross-sectional study. Receiver operating characteristic (ROC curve was used to determine the cut-off values of BMI and WC with optimum sensitivity and specificity for the detection of MCI. Age, gender, years of education, smoking habit, alcohol consumption, depression, and medical conditions were used as confounding factors in this analysis.Results: A BMI cut-off value of 26 kg/m2 (area under the receiver operating characteristic curve [AUC] 0.725; sensitivity 90.5%; specificity 38.8% was appropriate in identifying the risk of getting MCI in both men and women. The optimum WC cut-offs for likelihood of MCI were 90 cm (AUC 0.745; sensitivity 78.0%; specificity 59.8% for men and 82 cm (AUC 0.714; sensitivity 84.3%; specificity 49.7% for women. The optimum calf circumference (CC cut-off values for identifying MCI were 29 cm (AUC 0.731; sensitivity 72.6%; specificity

  10. Cross-cultural investigation into cognitive underpinnings of individual differences in early arithmetic.

    Science.gov (United States)

    Rodic, Maja; Zhou, Xinlin; Tikhomirova, Tatiana; Wei, Wei; Malykh, Sergei; Ismatulina, Victoria; Sabirova, Elena; Davidova, Yulia; Tosto, Maria Grazia; Lemelin, Jean-Pascal; Kovas, Yulia

    2015-01-01

    The present study evaluated 626 5-7-year-old children in the UK, China, Russia, and Kyrgyzstan on a cognitive test battery measuring: (1) general skills; (2) non-symbolic number sense; (3) symbolic number understanding; (4) simple arithmetic - operating with numbers; and (5) familiarity with numbers. Although most inter-population differences were small, 13% of the variance in arithmetic skills could be explained by the sample, replicating the pattern, previously found with older children in PISA. Furthermore, the same cognitive skills were related to early arithmetic in these diverse populations. Only understanding of symbolic number explained variation in mathematical performance in all samples. We discuss the results in terms of potential influences of socio-demographic, linguistic and genetic factors on individual differences in mathematics. © 2014 John Wiley & Sons Ltd.

  11. Pulsating variables

    International Nuclear Information System (INIS)

    1989-01-01

    The study of stellar pulsations is a major route to the understanding of stellar structure and evolution. At the South African Astronomical Observatory (SAAO) the following stellar pulsation studies were undertaken: rapidly oscillating Ap stars; solar-like oscillations in stars; 8-Scuti type variability in a classical Am star; Beta Cephei variables; a pulsating white dwarf and its companion; RR Lyrae variables and galactic Cepheids. 4 figs

  12. A systematic review of the neurobiological underpinnings of borderline personality disorder (BPD) in childhood and adolescence.

    Science.gov (United States)

    Winsper, Catherine; Marwaha, Steven; Lereya, Suzet Tanya; Thompson, Andrew; Eyden, Julie; Singh, Swaran P

    2016-12-01

    Contemporary theories for the aetiology of borderline personality disorder (BPD) take a lifespan approach asserting that inborn biological predisposition is potentiated across development by environmental risk factors. In this review, we present and critically evaluate evidence on the neurobiology of BPD in childhood and adolescence, compare this evidence to the adult literature, and contextualise within a neurodevelopmental framework. A systematic review was conducted to identify studies examining the neurobiological (i.e. genetic, structural neuroimaging, neurophysiological, and neuropsychological) correlates of BPD symptoms in children and adolescents aged 19 years or under. We identified, quality assessed, and narratively summarised 34 studies published between 1980 and June 2016. Similar to findings in adult populations, twin studies indicated moderate to high levels of heritability of BPD, and there was some evidence for gene-environment interactions. Also consistent with adult reports is that some adolescents with BPD demonstrated structural (grey and white matter) alterations in frontolimbic regions and neuropsychological abnormalities (i.e. reduced executive function and disturbances in social cognition). These findings suggest that neurobiological abnormalities observed in adult BPD may not solely be the consequence of chronic morbidity or prolonged medication use. They also provide tentative support for neurodevelopmental theories of BPD by demonstrating that neurobiological markers may be observed from childhood onwards and interact with environmental factors to increase risk of BPD in young populations. Prospective studies with a range of repeated measures are now required to elucidate the temporal unfurling of neurobiological features and further delineate the complex pathways to BPD.

  13. Conserving the stage: climate change and the geophysical underpinnings of species diversity.

    Directory of Open Access Journals (Sweden)

    Mark G Anderson

    Full Text Available Conservationists have proposed methods for adapting to climate change that assume species distributions are primarily explained by climate variables. The key idea is to use the understanding of species-climate relationships to map corridors and to identify regions of faunal stability or high species turnover. An alternative approach is to adopt an evolutionary timescale and ask ultimately what factors control total diversity, so that over the long run the major drivers of total species richness can be protected. Within a single climatic region, the temperate area encompassing all of the Northeastern U.S. and Maritime Canada, we hypothesized that geologic factors may take precedence over climate in explaining diversity patterns. If geophysical diversity does drive regional diversity, then conserving geophysical settings may offer an approach to conservation that protects diversity under both current and future climates. Here we tested how well geology predicts the species diversity of 14 US states and three Canadian provinces, using a comprehensive new spatial dataset. Results of linear regressions of species diversity on all possible combinations of 23 geophysical and climatic variables indicated that four geophysical factors; the number of geological classes, latitude, elevation range and the amount of calcareous bedrock, predicted species diversity with certainty (adj. R(2 = 0.94. To confirm the species-geology relationships we ran an independent test using 18,700 location points for 885 rare species and found that 40% of the species were restricted to a single geology. Moreover, each geology class supported 5-95 endemic species and chi-square tests confirmed that calcareous bedrock and extreme elevations had significantly more rare species than expected by chance (P<0.0001, strongly corroborating the regression model. Our results suggest that protecting geophysical settings will conserve the stage for current and future biodiversity and may

  14. Cognitive Variability

    Science.gov (United States)

    Siegler, Robert S.

    2007-01-01

    Children's thinking is highly variable at every level of analysis, from neural and associative levels to the level of strategies, theories, and other aspects of high-level cognition. This variability exists within people as well as between them; individual children often rely on different strategies or representations on closely related problems…

  15. Action of multiple intra-QTL genes concerted around a co-localized transcription factor underpins a large effect QTL

    Science.gov (United States)

    Dixit, Shalabh; Kumar Biswal, Akshaya; Min, Aye; Henry, Amelia; Oane, Rowena H.; Raorane, Manish L.; Longkumer, Toshisangba; Pabuayon, Isaiah M.; Mutte, Sumanth K.; Vardarajan, Adithi R.; Miro, Berta; Govindan, Ganesan; Albano-Enriquez, Blesilda; Pueffeld, Mandy; Sreenivasulu, Nese; Slamet-Loedin, Inez; Sundarvelpandian, Kalaipandian; Tsai, Yuan-Ching; Raghuvanshi, Saurabh; Hsing, Yue-Ie C.; Kumar, Arvind; Kohli, Ajay

    2015-01-01

    Sub-QTLs and multiple intra-QTL genes are hypothesized to underpin large-effect QTLs. Known QTLs over gene families, biosynthetic pathways or certain traits represent functional gene-clusters of genes of the same gene ontology (GO). Gene-clusters containing genes of different GO have not been elaborated, except in silico as coexpressed genes within QTLs. Here we demonstrate the requirement of multiple intra-QTL genes for the full impact of QTL qDTY12.1 on rice yield under drought. Multiple evidences are presented for the need of the transcription factor ‘no apical meristem’ (OsNAM12.1) and its co-localized target genes of separate GO categories for qDTY12.1 function, raising a regulon-like model of genetic architecture. The molecular underpinnings of qDTY12.1 support its effectiveness in further improving a drought tolerant genotype and for its validity in multiple genotypes/ecosystems/environments. Resolving the combinatorial value of OsNAM12.1 with individual intra-QTL genes notwithstanding, identification and analyses of qDTY12.1has fast-tracked rice improvement towards food security. PMID:26507552

  16. Genetic variability and bottleneck analyses of Kanni adu goat population using microsatellite markers [Also published in The Indian Journal of Small Ruminants, 2015, 21(2): 216-22

    International Nuclear Information System (INIS)

    Jeyakumar, M.; Thiruvenkadan, R.; Saravana, R.; Periasamy, K.

    2016-01-01

    Full text: Microsatellite data on 25 loci were generated and utilized to evaluate the genetic architecture and mutation drift equilibrium of Kanni Adu goats of southern Tamil Nadu. The genetic diversity analysis of Kanni Adu goats displayed higher level of within breed variability in terms of mean number of alleles per locus (11.24±0.87) and heterozygosity values (Ho= 0.677±0.041, He=0.857±0.016). Within population inbreeding estimate (FIS=0.215±0.040) showed moderate level of inbreeding, which warrant adoption of appropriate breeding strategies under field conditions. The polymorphism information content (PIC) value ranged from 0.531 to 0.915 suggested higher polymorphism in this breed. In general, the sign, standardized differences and Wilcoxon rank tests indicated heterozygosity excess in Kanni Adu goat population in infinite alleles and two-phase model and non-significant in stepwise mutation model. Hence, the mode-shift indicator test was utilized and it indicated the absence of genetic bottleneck in the recent past in Kanni Adu goats. It suggests that any unique alleles present in this breed may not have been lost. The study indicated that Kanni adu goats exhibited substantial amount of genetic variation as reflected from the heterozygosity and number of alleles per locus. (author)

  17. Does oral language underpin the development of later behavior problems? A longitudinal meta-analysis.

    Science.gov (United States)

    Chow, Jason C; Ekholm, Erik; Coleman, Heather

    2018-05-24

    The purpose of this article is to estimate the overall weighted mean effect of the relation between early language skills and later behavior problems in school-aged children. A systematic literature search yielded 19,790 unduplicated reports, and a structured search strategy and identification procedure yielded 25 unique data sets, with 114 effect sizes for analysis. Eligible reports were then coded, and effect sizes were extracted and synthesized via robust variance estimation and random-effects meta-analytic techniques. The overall correlation between early language and later behavior problems was negative and small (r = -.14, 95% confidence interval [CI] [-.16, -.11]), and controlling for demographic variables did not reduce the magnitude of the inverse relationship between language skill and problem behavior (r = -.16). Moderator analyses identified receptive language, parent-reported behavior measures, gender, and age as significant predictors of the association between language and behavior. This article corroborates the consistent findings of previous meta-analytic and longitudinal studies and further identifies areas, particularly around measurement, for future research. Furthermore, prospective longitudinal evaluations of the relations between language deficits and behavior problems with different types of measures (teacher-/parent-report, direct assessment, classroom observation) is warranted. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  18. Multiple brain networks underpinning word learning from fluent speech revealed by independent component analysis.

    Science.gov (United States)

    López-Barroso, Diana; Ripollés, Pablo; Marco-Pallarés, Josep; Mohammadi, Bahram; Münte, Thomas F; Bachoud-Lévi, Anne-Catherine; Rodriguez-Fornells, Antoni; de Diego-Balaguer, Ruth

    2015-04-15

    Although neuroimaging studies using standard subtraction-based analysis from functional magnetic resonance imaging (fMRI) have suggested that frontal and temporal regions are involved in word learning from fluent speech, the possible contribution of different brain networks during this type of learning is still largely unknown. Indeed, univariate fMRI analyses cannot identify the full extent of distributed networks that are engaged by a complex task such as word learning. Here we used Independent Component Analysis (ICA) to characterize the different brain networks subserving word learning from an artificial language speech stream. Results were replicated in a second cohort of participants with a different linguistic background. Four spatially independent networks were associated with the task in both cohorts: (i) a dorsal Auditory-Premotor network; (ii) a dorsal Sensory-Motor network; (iii) a dorsal Fronto-Parietal network; and (iv) a ventral Fronto-Temporal network. The level of engagement of these networks varied through the learning period with only the dorsal Auditory-Premotor network being engaged across all blocks. In addition, the connectivity strength of this network in the second block of the learning phase correlated with the individual variability in word learning performance. These findings suggest that: (i) word learning relies on segregated connectivity patterns involving dorsal and ventral networks; and (ii) specifically, the dorsal auditory-premotor network connectivity strength is directly correlated with word learning performance. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Genetic variability in natural populations of Zeyheria montana mart. from the Brazilian Cerrado Variabilidade genética entre e dentro de populações naturais de Zeyheria montana mart. do Cerrado brasileiro

    Directory of Open Access Journals (Sweden)

    Bianca Waléria Bertoni

    2007-08-01

    Full Text Available Zeyheria montana, an endemic species of the Bignoniaceae family from the Brazilian Cerrado's known for its anti-cancer properties, is widely used as imuno stimulant in the popular medicine and its therapeutic activity must be validated by scientific data. The objective of this work was to evaluate the genetic variability of eight plant populations collected within the state of São Paulo, Brazil, via Random Amplification of Polymorphic DNA (RAPD used as molecular markers. After an optimized protocol for the amplification reaction, nine selected primers generated 105 reproducible bands, indicating up to 60% polymorphism. Analysis of molecular variance (AMOVA revealed higher genetic variation within populations (84.03% than among populations (15.97%. The variation values estimated by phiST (0.160 indicated moderate to high inter population structuration. Levels of similarity inter plants with genetic and geographical distances, estimated by the unweighted pair-group method analysis (UPGMA clustering and non-metric multidimensional scaling (NMDS ordination methods and by the Mantel test (-0.2345 p = 0.118 denoted that the structure found follows the island model, which assumes that a single population of infinite size may have initiated the existing populations of Zeyheria montana, with no spatial position correlation. Based on the obtained data, a germplasm bank from individuals representing the species variability was established. Furthermore the information here reported can be of importance to develop strategies for the conservation of Z. montana.Zeyheria montana, planta arbustiva da família Bignoniaceae, é uma espécie endêmica do Cerrado e possui atividade anti-câncer, sendo utilizada como estimulante na medicina popular. O objetivo deste estudo foi avaliar a variabilidade genética de oito populações localizadas no estado de São Paulo, utilizando marcadores moleculares de Polimorfismo de DNA Amplificado ao Acaso (RAPD. Após a otimiza

  20. Host behaviour and physiology underpin individual variation in avian influenza virus infection in migratory Bewick's swans.

    Science.gov (United States)

    Hoye, Bethany J; Fouchier, Ron A M; Klaassen, Marcel

    2012-02-07

    Individual variation in infection modulates both the dynamics of pathogens and their impact on host populations. It is therefore crucial to identify differential patterns of infection and understand the mechanisms responsible. Yet our understanding of infection heterogeneity in wildlife is limited, even for important zoonotic host-pathogen systems, owing to the intractability of host status prior to infection. Using novel applications of stable isotope ecology and eco-immunology, we distinguish antecedent behavioural and physiological traits associated with avian influenza virus (AIV) infection in free-living Bewick's swans (Cygnus columbianus bewickii). Swans infected with AIV exhibited higher serum δ13C (-25.3±0.4) than their non-infected counterparts (-26.3±0.2). Thus, individuals preferentially foraging in aquatic rather than terrestrial habitats experienced a higher risk of infection, suggesting that the abiotic requirements of AIV give rise to heterogeneity in pathogen exposure. Juveniles were more likely to be infected (30.8% compared with 11.3% for adults), shed approximately 15-fold higher quantity of virus and exhibited a lower specific immune response than adults. Together, these results demonstrate the potential for heterogeneity in infection to have a profound influence on the dynamics of pathogens, with concomitant impacts on host habitat selection and fitness.

  1. An integrated organisation-wide data quality management and information governance framework: theoretical underpinnings.

    Science.gov (United States)

    Liaw, Siaw-Teng; Pearce, Christopher; Liyanage, Harshana; Liaw, Gladys S S; de Lusignan, Simon

    2014-01-01

    Increasing investment in eHealth aims to improve cost effectiveness and safety of care. Data extraction and aggregation can create new data products to improve professional practice and provide feedback to improve the quality of source data. A previous systematic review concluded that locally relevant clinical indicators and use of clinical record systems could support clinical governance. We aimed to extend and update the review with a theoretical framework. We searched PubMed, Medline, Web of Science, ABI Inform (Proquest) and Business Source Premier (EBSCO) using the terms curation, information ecosystem, data quality management (DQM), data governance, information governance (IG) and data stewardship. We focused on and analysed the scope of DQM and IG processes, theoretical frameworks, and determinants of the processing, quality assurance, presentation and sharing of data across the enterprise. There are good theoretical reasons for integrated governance, but there is variable alignment of DQM, IG and health system objectives across the health enterprise. Ethical constraints exist that require health information ecosystems to process data in ways that are aligned with improving health and system efficiency and ensuring patient safety. Despite an increasingly 'big-data' environment, DQM and IG in health services are still fragmented across the data production cycle. We extend current work on DQM and IG with a theoretical framework for integrated IG across the data cycle. The dimensions of this theory-based framework would require testing with qualitative and quantitative studies to examine the applicability and utility, along with an evaluation of its impact on data quality across the health enterprise.

  2. An integrated organisation-wide data quality management and information governance framework: theoretical underpinnings

    Directory of Open Access Journals (Sweden)

    Siaw-Teng Liaw

    2014-10-01

    Full Text Available Introduction Increasing investment in eHealth aims to improve cost effectiveness and safety of care. Data extraction and aggregation can create new data products to improve professional practice and provide feedback to improve the quality of source data. A previous systematic review concluded that locally relevant clinical indicators and use of clinical record systems could support clinical governance. We aimed to extend and update the review with a theoretical framework.Methods We searched PubMed, Medline, Web of Science, ABI Inform (Proquest and Business Source Premier (EBSCO using the terms curation, information ecosystem, data quality management (DQM, data governance, information governance (IG and data stewardship. We focused on and analysed the scope of DQM and IG processes, theoretical frameworks, and determinants of the processing, quality assurance, presentation and sharing of data across the enterprise.Findings There are good theoretical reasons for integrated governance, but there is variable alignment of DQM, IG and health system objectives across the health enterprise. Ethical constraints exist that require health information ecosystems to process data in ways that are aligned with improving health and system efficiency and ensuring patient safety. Despite an increasingly ‘big-data’ environment, DQM and IG in health services are still fragmented across the data production cycle. We extend current work on DQM and IG with a theoretical framework for integrated IG across the data cycle.Conclusions The dimensions of this theory-based framework would require testing with qualitative and quantitative studies to examine the applicability and utility, along with an evaluation of its impact on data quality across the health enterprise.

  3. Scientific imperatives, clinical implications, and theoretical underpinnings for the investigation of the relationship between genetic variables and patient-reported quality-of-life outcomes

    NARCIS (Netherlands)

    Sprangers, Mirjam A. G.; Sloan, Jeff A.; Barsevick, Andrea; Chauhan, Cynthia; Dueck, Amylou C.; Raat, Hein; Shi, Quiling; van Noorden, Cornelis J. F.; Abernethy, Amy P.; Baas, Frank; Barsevick, Andrea M.; Bartels, Meike; Boomsma, Dorret I.; Bottomley, Andrew; Brundage, Michael; Cella, David; Cleeland, Charles S.; Coens, Corneel; Frost, Marlene H.; Hall, Per; Halyard, Michele Y.; Klepstad, Pål; Martin, Nicholas G.; Miaskowski, Christine; Mosing, Miriam; Movsas, Benjamin; Oliveira, Joao R.; Ordoñana, Juan; Patrick, Donald L.; Pedersen, Nancy L.; Reeve, Bryce; Ropka, Mary E.; Shinozaki, Gen; Singh, Jasvinder A.; Swaab, Dick; Veenhoven, Ruut; Wagner, Gert; Yang, Ping; Zwinderman, Ailko H.

    2010-01-01

    Objectives There is emerging evidence for a genetic basis of patient-reported quality-of-life (QOL) outcomes that can ultimately be incorporated into clinical research and practice. Objectives are (1) to provide arguments for the timeliness of investigating the genetic basis of QOL given the

  4. Evolution of variable stars

    International Nuclear Information System (INIS)

    Becker, S.A.

    1986-08-01

    Throughout the domain of the H R diagram lie groupings of stars whose luminosity varies with time. These variable stars can be classified based on their observed properties into distinct types such as β Cephei stars, δ Cephei stars, and Miras, as well as many other categories. The underlying mechanism for the variability is generally felt to be due to four different causes: geometric effects, rotation, eruptive processes, and pulsation. In this review the focus will be on pulsation variables and how the theory of stellar evolution can be used to explain how the various regions of variability on the H R diagram are populated. To this end a generalized discussion of the evolutionary behavior of a massive star, an intermediate mass star, and a low mass star will be presented. 19 refs., 1 fig., 1 tab

  5. Transactive System: Part I: Theoretical Underpinnings of Payoff Functions, Control Decisions, Information Privacy, and Solution Concepts

    Energy Technology Data Exchange (ETDEWEB)

    Lian, Jianming [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zhang, Wei [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Sun, Y. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Marinovici, Laurentiu D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kalsi, Karanjit [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Widergren, Steven E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2018-01-17

    The increased penetration of renewable energy has significantly changed the conditions and the operational timing of the electricity grid. More flexible, faster ramping resources are needed to compensate for the uncertainty and variability introduced by renewable energy. Distributed energy resources (DERs) such as distributed generators, energy storage, and controllable loads could help manage the power grid in terms of both economic efficiency and operational reliability. In order to realize the benefits of DERs, coordination and control approaches must be designed to enable seamless integration of DERs into the power grid. Transactive coordination and control is a new approach for DER integration, where individual resources are automated and engaged through market interaction. Transactive approaches use economic signals—prices or incentives—to engage DERs. These economic signals must reflect the true value of the DER contributions, so that they seamlessly and equitably compete for the opportunities that today are only available to grid-owned assets. Value signals must be communicated to the DERs in near-real time, the assets must be imbued with new forms of distributed intelligence and control to take advantage of the opportunities presented by these signals, and they must be capable of negotiating and transacting a range of market-driven energy services. The concepts of transactive energy systems are not new, but build upon evolutionary economic changes in financial and electric power markets. These concepts also recognize the different regional structures of wholesale power markets, electricity delivery markets, retail markets, and vertically integrated service provider markets. Although transactive energy systems are not revolutionary, they will be transformational in their ability to provide flexibility and operational efficiency. A main goal of this research is to establish useful foundation for analysis of transactive energy systems and to facilitate

  6. Practice as ‘Research’ Within The Context of Art and Design Academia: A Brief Excursion Into Its Philosophical Underpinnings

    Directory of Open Access Journals (Sweden)

    Dominique Rio Adiwijaya

    2015-07-01

    Full Text Available Integration of many fields of human endeavor including art and design into academic system is not at all surprising in our modern world that continues to modernize itself in the quest for ever increasing welfare of humanity. The backbone of modern welfare is unmistakably techno-scientific academic research, explaining current expansion of its ‘standardized’ paradigm, regulation and infrastructure without exception into the field of art and design. This is where the problem precisely arises, since their own nature, art and design as ‘creative’ fields, are incompatible with scientific paradigm which emphasizes a uniform reproducibility of research findings. ‘The heart of the arts’, in contrast, is its singularities. The industry actually has recognized the difference by assigning ‘patents’ to technological invention and ‘copyright’ to singular artworks. The question is then how to incorporate such creatively plural fields into uniform academic research system. Fortunately within the past 20 years, there were developments within international art and design academia that came up with a keystone principle called practice-based research. It relies upon philosophical underpinnings of phenomenology and hermeneutics which has been critically acclaimed in showing inadequacies of positivistic (natural science-based paradigm in understanding cultural phenomena exemplified by art and design. It is the intention of this article to briefly explain this new principle and its philosophical underpinnings in order to let us appreciate its positive contribution for our understanding of art and design. This understanding in turn would allow us to cultivate those creative fields within academic context in a more appropriate way. 

  7. Mesoscale spatiotemporal variability in a complex host-parasite system influenced by intermediate host body size

    Directory of Open Access Journals (Sweden)

    Sara M. Rodríguez

    2017-08-01

    Full Text Available Background Parasites are essential components of natural communities, but the factors that generate skewed distributions of parasite occurrences and abundances across host populations are not well understood. Methods Here, we analyse at a seascape scale the spatiotemporal relationships of parasite exposure and host body-size with the proportion of infected hosts (i.e., prevalence and aggregation of parasite burden across ca. 150 km of the coast and over 22 months. We predicted that the effects of parasite exposure on prevalence and aggregation are dependent on host body-sizes. We used an indirect host-parasite interaction in which migratory seagulls, sandy-shore molecrabs, and an acanthocephalan worm constitute the definitive hosts, intermediate hosts, and endoparasite, respectively. In such complex systems, increments in the abundance of definitive hosts imply increments in intermediate hosts’ exposure to the parasite’s dispersive stages. Results Linear mixed-effects models showed a significant, albeit highly variable, positive relationship between seagull density and prevalence. This relationship was stronger for small (cephalothorax length >15 mm than large molecrabs (<15 mm. Independently of seagull density, large molecrabs carried significantly more parasites than small molecrabs. The analysis of the variance-to-mean ratio of per capita parasite burden showed no relationship between seagull density and mean parasite aggregation across host populations. However, the amount of unexplained variability in aggregation was strikingly higher in larger than smaller intermediate hosts. This unexplained variability was driven by a decrease in the mean-variance scaling in heavily infected large molecrabs. Conclusions These results show complex interdependencies between extrinsic and intrinsic population attributes on the structure of host-parasite interactions. We suggest that parasite accumulation—a characteristic of indirect host

  8. Mesoscale spatiotemporal variability in a complex host-parasite system influenced by intermediate host body size.

    Science.gov (United States)

    Rodríguez, Sara M; Valdivia, Nelson

    2017-01-01

    Parasites are essential components of natural communities, but the factors that generate skewed distributions of parasite occurrences and abundances across host populations are not well understood. Here, we analyse at a seascape scale the spatiotemporal relationships of parasite exposure and host body-size with the proportion of infected hosts (i.e., prevalence) and aggregation of parasite burden across ca. 150 km of the coast and over 22 months. We predicted that the effects of parasite exposure on prevalence and aggregation are dependent on host body-sizes. We used an indirect host-parasite interaction in which migratory seagulls, sandy-shore molecrabs, and an acanthocephalan worm constitute the definitive hosts, intermediate hosts, and endoparasite, respectively. In such complex systems, increments in the abundance of definitive hosts imply increments in intermediate hosts' exposure to the parasite's dispersive stages. Linear mixed-effects models showed a significant, albeit highly variable, positive relationship between seagull density and prevalence. This relationship was stronger for small (cephalothorax length >15 mm) than large molecrabs (analysis of the variance-to-mean ratio of per capita parasite burden showed no relationship between seagull density and mean parasite aggregation across host populations. However, the amount of unexplained variability in aggregation was strikingly higher in larger than smaller intermediate hosts. This unexplained variability was driven by a decrease in the mean-variance scaling in heavily infected large molecrabs. These results show complex interdependencies between extrinsic and intrinsic population attributes on the structure of host-parasite interactions. We suggest that parasite accumulation-a characteristic of indirect host-parasite interactions-and subsequent increasing mortality rates over ontogeny underpin size-dependent host-parasite dynamics.

  9. Complex variables

    CERN Document Server

    Fisher, Stephen D

    1999-01-01

    The most important topics in the theory and application of complex variables receive a thorough, coherent treatment in this introductory text. Intended for undergraduates or graduate students in science, mathematics, and engineering, this volume features hundreds of solved examples, exercises, and applications designed to foster a complete understanding of complex variables as well as an appreciation of their mathematical beauty and elegance. Prerequisites are minimal; a three-semester course in calculus will suffice to prepare students for discussions of these topics: the complex plane, basic

  10. Variabilidade genética de populações naturais de caroá por meio de marcadores RAPD Genetic variability estimated among caroá populations through RAPD markers

    Directory of Open Access Journals (Sweden)

    Daniela Garcia Silveira

    2009-03-01

    Full Text Available O objetivo deste trabalho foi quantificar a variabilidade genética entre e dentro de populações de caroá (Neoglaziovia variegata, por meio de marcadores "random amplified polymorphic DNA" (RAPD. Foram analisados 180 genótipos de caroá, provenientes dos municípios de Guanambi, Juazeiro e Valente, no Estado da Bahia. Foi observado elevado polimorfismo entre as populações de caroá. As dissimilaridades genéticas entre os genótipos variaram de 0,08 a 0,95, com média de 0,44.Avariância molecular mostrou que 56% da variação total foi explicada pelas diferenças entre indivíduos dentro de locais. As diferenças entre municípios explicaram 17% da variação total, enquanto as diferenças entre locais dentro dos municípios explicaram 26% da variação.The objective of this work was to quantify the genetic variability within and among populations of caroá (Neoglaziovia variegata using random amplified polymorphic DNA(RAPD markers. One hundred eighty caroá genotypes from Guanambi, Juazeiro and Valente counties in the state of Bahia, Brazil, were analyzed. A high polymorphism was observed among the caroá populations. The genetic dissimilarities among all genotypes ranged from 0.08 to 0.95 with an average of 0.44. The molecular variance showed that 56% of the total variation was explained by the differences among individuals with in locations.The differences among counties explained 17% of the total variation, while the differences among places within counties explained 26% of the variation.

  11. Variable stars

    International Nuclear Information System (INIS)

    Feast, M.W.; Wenzel, W.; Fernie, J.D.; Percy, J.R.; Smak, J.; Gascoigne, S.C.B.; Grindley, J.E.; Lovell, B.; Sawyer Hogg, H.B.; Baker, N.; Fitch, W.S.; Rosino, L.; Gursky, H.

    1976-01-01

    A critical review of variable stars is presented. A fairly complete summary of major developments and discoveries during the period 1973-1975 is given. The broad developments and new trends are outlined. Essential problems for future research are identified. (B.R.H. )

  12. How do you assign persistent identifiers to extracts from large, complex, dynamic data sets that underpin scholarly publications?

    Science.gov (United States)

    Wyborn, Lesley; Car, Nicholas; Evans, Benjamin; Klump, Jens

    2016-04-01

    Persistent identifiers in the form of a Digital Object Identifier (DOI) are becoming more mainstream, assigned at both the collection and dataset level. For static datasets, this is a relatively straight-forward matter. However, many new data collections are dynamic, with new data being appended, models and derivative products being revised with new data, or the data itself revised as processing methods are improved. Further, because data collections are becoming accessible as services, researchers can log in and dynamically create user-defined subsets for specific research projects: they also can easily mix and match data from multiple collections, each of which can have a complex history. Inevitably extracts from such dynamic data sets underpin scholarly publications, and this presents new challenges. The National Computational Infrastructure (NCI) has been experiencing and making progress towards addressing these issues. The NCI is large node of the Research Data Services initiative (RDS) of the Australian Government's research infrastructure, which currently makes available over 10 PBytes of priority research collections, ranging from geosciences, geophysics, environment, and climate, through to astronomy, bioinformatics, and social sciences. Data are replicated to, or are produced at, NCI and then processed there to higher-level data products or directly analysed. Individual datasets range from multi-petabyte computational models and large volume raster arrays, down to gigabyte size, ultra-high resolution datasets. To facilitate access, maximise reuse and enable integration across the disciplines, datasets have been organized on a platform called the National Environmental Research Data Interoperability Platform (NERDIP). Combined, the NERDIP data collections form a rich and diverse asset for researchers: their co-location and standardization optimises the value of existing data, and forms a new resource to underpin data-intensive Science. New publication

  13. Social Assistance: Theoretical Underpinnings

    African Journals Online (AJOL)

    user

    their own pivotal roles in making for mature and great societies have been ... Need of course comes in its physical and psycho-social gaps with the .... imposed the burden of inequality on an otherwise just man. .... are physically able to work.

  14. Underpinning Land Management

    DEFF Research Database (Denmark)

    Enemark, Stig

    This paper provides an overall understanding of the concept of land administration systems for dealing with rights, restrictions and responsibilities in future spatially enabled government. Further, the paper presents the role of FIG with regard to building the capacity in this area and responding...

  15. Neural underpinnings of music

    DEFF Research Database (Denmark)

    Vuust, Peter; Gebauer, Line K; Witek, Maria A G

    2014-01-01

    . According to this theory, perception and learning is manifested through the brain’s Bayesian minimization of the error between the input to the brain and the brain’s prior expectations. Fourth, empirical studies of neural and behavioral effects of syncopation, polyrhythm and groove will be reported, and we...

  16. Complex variables

    CERN Document Server

    Flanigan, Francis J

    2010-01-01

    A caution to mathematics professors: Complex Variables does not follow conventional outlines of course material. One reviewer noting its originality wrote: ""A standard text is often preferred [to a superior text like this] because the professor knows the order of topics and the problems, and doesn't really have to pay attention to the text. He can go to class without preparation."" Not so here-Dr. Flanigan treats this most important field of contemporary mathematics in a most unusual way. While all the material for an advanced undergraduate or first-year graduate course is covered, discussion

  17. Impaired endocannabinoid signalling in the rostral ventromedial medulla underpins genotype-dependent hyper-responsivity to noxious stimuli.

    Science.gov (United States)

    Rea, Kieran; Olango, Weredeselam M; Okine, Bright N; Madasu, Manish K; McGuire, Iseult C; Coyle, Kathleen; Harhen, Brendan; Roche, Michelle; Finn, David P

    2014-01-01

    Pain is both a sensory and an emotional experience, and is subject to modulation by a number of factors including genetic background modulating stress/affect. The Wistar-Kyoto (WKY) rat exhibits a stress-hyper-responsive and depressive-like phenotype and increased sensitivity to noxious stimuli, compared with other rat strains. Here, we show that this genotype-dependent hyperalgesia is associated with impaired pain-related mobilisation of endocannabinoids and transcription of their synthesising enzymes in the rostral ventromedial medulla (RVM). Pharmacological blockade of the Cannabinoid1 (CB1) receptor potentiates the hyperalgesia in WKY rats, whereas inhibition of the endocannabinoid catabolising enzyme, fatty acid amide hydrolase, attenuates the hyperalgesia. The latter effect is mediated by CB1 receptors in the RVM. Together, these behavioural, neurochemical, and molecular data indicate that impaired endocannabinoid signalling in the RVM underpins hyper-responsivity to noxious stimuli in a genetic background prone to heightened stress/affect. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  18. Beyond the diagnostic traits: a collaborative exploratory diagnostic process for dimensions and underpinnings of narcissistic personality disorder.

    Science.gov (United States)

    Ronningstam, Elsa

    2014-10-01

    Narcissistic personality disorder has been challenging to diagnose in psychiatric and general clinical practice. Several circumstances and personality factors related to the nature of pathological narcissism and NPD contribute. NPD is usually a moderately impairing condition, often accompanied by specific capabilities and high level of functioning. Comorbidity of other urgent and recognizable psychiatric conditions, such as mood and substance use disorders or suicidality, can override even significant narcissistic personality functioning. Patients' limited ability to recognize own contribution to problems or impact on other people, their hypersensitivity and defensive reactivity, and compromised ability for self-disclosure, self-reflection, and emotional empathy can make initial evaluations difficult. The aim of this study is to integrate recent clinical and empirical knowledge on the underpinnings of pathological narcissism and narcissistic personality functioning, and distinguish narcissistic self-regulatory patterns that are affecting diagnostic traits. A more flexible, exploratory, and collaborative diagnostic process is proposed that integrates the patients subjective experiences and interpersonal functioning in terms of self-regulation, agency, and traits in a way that is informative and meaningful for both the patient and the clinician. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  19. Impact of demographic and clinical variables on the oral health-related quality of life among five-year-old children: a population-based study using self-reports.

    Science.gov (United States)

    Abanto, Jenny; Panico, Claudia; Bönecker, Marcelo; Frazão, Paulo

    2018-01-01

    Although SOHO-5 has been validated, there is no study testing this instrument in population-based samples. To evaluate the impact of demographic and oral clinical variables on the oral health-related quality of life (OHRQoL) in 5-year-old children from a socially deprived Brazilian area using selfreports. Data from 588 children were analyzed. Examinations included untreated dental caries and occlusal deviations. Children answered the Brazilian SOHO-5 version and interviewers collected demographic characteristics of the child (sex and skin color). Robust Poisson regression associated outcome and exposures. General, the oral impacts were reported by 71.1% of children. The mean and standard deviation total score of the Brazilian SOHO-5 were 3.51 and 3.82, respectively. Children with untreated dental caries (PR = 1.28; P = 0.004) and increased overjet (PR = 1.35; P = 0.002) experienced a worse OHRQoL. Dark and mixed skin color children did not have a good impact on their OHRQoL (PR = 1.53; P = 0.006 and PR = 1.44; P < 0.000, respectively) compared to light ones. Untreated dental caries and increased overjet were independently associated with worst OHRQoL in 5-year-old children. As an indication of social deprivation, dark and mixed skin color children compared to light ones presented higher probability for reporting worst OHRQoL independently of the oral clinical conditions. © 2017 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Exploring the Philosophical Underpinnings of Research: Relating Ontology and Epistemology to the Methodology and Methods of the Scientific, Interpretive, and Critical Research Paradigms

    Science.gov (United States)

    Scotland, James

    2012-01-01

    This paper explores the philosophical underpinnings of three major educational research paradigms: scientific, interpretive, and critical. The aim was to outline and explore the interrelationships between each paradigm's ontology, epistemology, methodology and methods. This paper reveals and then discusses some of the underlying assumptions of…

  1. F229. THE BIOLOGICAL UNDERPINNINGS OF TREATMENT RESPONSE IN DELUSIONAL DISORDER: A SYSTEMATIC REVIEW OF QUALITATIVE EVIDENCE-TO-DATE

    Science.gov (United States)

    González-Rodríguez, Alexandre; Estrada, Francesc; Montalvo, Itziar; Monreal, José Antonio; Palao, Diego; Labad, Javier

    2018-01-01

    Abstract Background The dopamine hypothesis of schizophrenia has been extensively proposed as a neurobiological mechanism that explains the relationship between schizophrenic symptoms and hyperdopaminergic states. This hypothesis is supported by direct and indirect evidence, and it mainly postulates that antipsychotics act blocking dopamine receptors. When focusing on delusional disorder patients, especially delusional disorder somatic type, a great effort towards the search for a biological basis of treatment response has been recently demonstrated. Thus, the main goal of this systematic review was to examine the evidence explaining the biological underpinnings of treatment response in delusional disorder. Methods A systematic review was performed using Pubmed, Scopus and PsycINFO databases (from 1990 to October 2017), according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The following search terms were used: [(‘treat*’ OR ‘therap*’ OR ‘biol*’) AND (‘delusional disorder’)]. This systematic computerized search was completed by additional studies hand-checked through reference lists from the included studies and review articles. Studies were only included if the met our inclusion criteria: (a) the International Classification of Diseases (ICD) or Diagnostic and Statistical Manual of Mental Disorders (DSM) diagnosis for delusional disorder, (b) be published in peer-reviewed journals, (c) in English, German or Spanish, (d) and reporting a hypothesis for the biological basis of treatment response in delusional disorder, irrespective of method and study design. Exclusion criteria were: (a) studies including organic delusional disorder or (b) somatic delusions secondary to other psychiatric diagnoses. The literature search strategy, data extraction and synthesis was conducted independently by two authors (A.G.R, F.E.). When disagreement, it was solved by consensus. Results A total of 59 articles were

  2. THE UNDERPINNING ASPECTS OF THE SUCCESSFUL PARTICIPANT IN THE NATIONAL STORY TELLING COMPETITION OF JUNIOR HIGH LEVEL IN 2014

    Directory of Open Access Journals (Sweden)

    Sukma Nur Ardini

    2017-04-01

    The results obtained show that there are five aspects that underpin the success of participants namely cognitive, creativity, infrastructure facilities, support and motivation aspects. The top ten participants highly own those aspects by using almost all the time to communicate in English in their daily lives. Moreover, none of them who bring the story by memorizing the text but they understand the story and the flow of the story as well. The height of creativity they proved by telling the story with their own style and improvise more without changing the idea of the story. Moreover, the ideas of stories they bring in the competition emerged from the participants. Similarly to aspects of infrastructure and support facilities, they get the costume and property as well as the full support of the school, teachers, families and government. Their motivation was not material but performance, and they always accept the challenge as a positive thing and not easily satisfied with what they have accomplished. Evaluation criteria such as communication, expression and creativity as well as environmental factors which also support the participants are found as the winning background. In fact, the appearance of those aspects is the benefits that can bolster their success more superior than other participant who are already loose. Thus, it can be concluded that by having those aspects, participants are able to know their lack in order to reach the victory. Therefore, it is hoped that this study can be socializedto all participants as well as observers so this study can be a reference to develop and find new potentials dealing with story telling competition.

  3. Binge Drinking and the Young Brain: A Mini Review of the Neurobiological Underpinnings of Alcohol-Induced Blackout

    Directory of Open Access Journals (Sweden)

    Daniel F. Hermens

    2018-01-01

    Full Text Available Binge drinking has significant effects on memory, particularly with regards to the transfer of information to long-term storage. Partial or complete blocking of memory formation is known as blackout. Youth represents a critical period in brain development that is particularly vulnerable to alcohol misuse. Animal models show that the adolescent brain is more vulnerable to the acute and chronic effects of alcohol compared with the adult brain. This mini-review addresses the neurobiological underpinnings of binge drinking and associated memory loss (blackout in the adolescent and young adult period. Although the extent to which there are pre-existing versus alcohol-induced neurobiological changes remains unclear, it is likely that repetitive binge drinking in youth has detrimental effects on cognitive and social functioning. Given its role in learning and memory, the hippocampus is a critical region with neuroimaging research showing notable changes in this structure associated with alcohol misuse in young people. There is a great need for earlier identification of biological markers associated with alcohol-related brain damage. As a means to assess in vivo neurochemistry, magnetic resonance spectroscopy (MRS has emerged as a particularly promising technique since changes in neurometabolites often precede gross structural changes. Thus, the current paper addresses how MRS biomarkers of neurotransmission (glutamate, GABA and oxidative stress (indexed by depleted glutathione in the hippocampal region of young binge drinkers may underlie propensity for blackouts and other memory impairments. MRS biomarkers may have particular utility in determining the acute versus longer-term effects of binge drinking in young people.

  4. Looking at Organizational Change Through the Construction and Reconstruction of the Underpinning Values of the Organization Through Interactions Among Stakeholders

    Directory of Open Access Journals (Sweden)

    Sueli dos Santos Leitão

    2015-09-01

    Full Text Available Objective – This paper attempts to understand how the stakeholders in an organization - which strives to achieve goals that are sometimes in conflict - construct and reconstruct (through their interactions their beliefs (values related to organizational competition and habits of action (practices. Design/methodology/approach – A qualitative single case study was conducted at a tax consulting firm in the service sector in Brazil, with ongoing organizational change. The firm seeks to find an even balance between fostering human and social development and financial earnings. Semi-structured and in-depth interviews were conducted with the founder, employees, customers and suppliers, in addition to nonparticipant observation, naturally occurring discussions, and documents. Findings – The analysis of the discursive materials showed that organizational practices reflect values formed over several years through the paradoxical tension between the world views of the founder on how the business world actually is and how it should be. The value of “coherence between what is said and what is done” permeated several reflexivity practices, when decisions were taken and the reasons underpinning them were discussed by management and employees, in pursuit of the goals initially proposed. Practical implications – This research contributes to wider-ranging reflections on the competitive world of organizations dealing with the challenges that face them, extending beyond social responsibility. It also illustrates that reflexivity may be particularly helpful in other forprofit organizations, particularly those focused on social innovation. Originality/value – This study promotes a discussion of change as a continuous process, grounded on a differentiated approach to organizational values, highlighting the emerging characteristics of organizational becoming.

  5. Cardiometabolic Risk and Female Sexuality-Part I. Risk Factors and Potential Pathophysiological Underpinnings for Female Vasculogenic Sexual Dysfunction Syndromes.

    Science.gov (United States)

    Maseroli, Elisa; Scavello, Irene; Vignozzi, Linda

    2018-05-02

    Erectile dysfunction is recognized as an opportunity for preventing cardiovascular (CV) events, and assessing the impairment of penile vascular flow by Doppler ultrasound is an important tool to ascertain CV risk. Conversely, the role of genital vascular impairment in the pathophysiology of female sexual dysfunction (FSD) remains contentious. To focus on the current scientific support for an association between CV risk factors and female sexual health in the 1st part of a 2-part review. A thorough literature search of peer-reviewed publications on the associations between CV risk factors and FSD and their underlying mechanisms was performed using the PubMed database. We present a summary of the evidence from clinical studies and discuss the possible mechanisms providing the pathophysiologic bases of vasculogenic FSD syndromes. The peripheral sexual response in women is a vascular-dependent event, and evidence suggests that cardiometabolic-related perturbations in endothelial function can determine vascular insufficiency in female genital tissues. Although epidemiologic and observational studies demonstrate that the prevalence of FSD is higher in women with diabetes mellitus, a cause-effect relation between these clinical conditions cannot be assumed. Evidence on the effect of obesity, metabolic syndrome, and polycystic ovary syndrome on sexual function in women is controversial. Data on the associations of dyslipidemia and hypertension with FSD are limited. Common cardiometabolic alterations could affect vascular function in the female genital tract. Based on limited data, there is an association between CV risk factors and female sexual health in women; however, this association appears milder than in men. Maseroli E, Scavello I, Vignozzi L. Cardiometabolic Risk and Female Sexuality-Part I. Risk Factors and Potential Pathophysiological Underpinnings for Female Vasculogenic Sexual Dysfunction Syndromes. Sex Med Rev 2018;X:XXX-XXX. Copyright © 2018 International

  6. Inter-population thermal variability and physiological response in the intertidal fish Scartichthys viridis (Blenniidae Variabilidad térmica intrapoblacional y respuesta fisiológica en el pez intermareal Scartichthys viridis (Blenniidae

    Directory of Open Access Journals (Sweden)

    JOSÉ M PULGAR

    2007-12-01

    Full Text Available Determining habitat conditions that generate individual physiological variability represents key basic knowledge to understand the direction of animal's responses to habitat change. The coastal fish Scartichthys viridis inhabits low intertidal pools along the Chilean coast. Because seawater in the low intertidal is renewed during every tidal cycle, this zone is characterized by a low thermal variation and abundant food within and between localities. We evaluated whether seawater thermal conditions and food availability of low intertidal pools registered in three localities of Chilean coast are sufficient to generate physiological and energetic differences in individuals of S. viridis captured from three geographic separate populations spanning approximately 1,200 km. Southern fishes acclimatized to 25 °C showed higher metabolic rates than those from other localities and thermal treatments. On the other hand, southern fishes in natural conditions showed higher condition factor than northern fishes. This evidence is sufficient to indicate that slight latitudinal differences in tidepool seawater temperature associated to differential food availability induced an energetic constraint in this species. Moreover, southern population of S. viridis may suffer important effects on energetic allocation if seawater temperature increases slightly, with repercussions on its geographic distribution in southern Pacific OceanDeterminar las condiciones del ambiente que generan variabilidad fisiológica, representa un conocimiento básico para comprender el sentido de la respuesta de los animales a los cambios en su habitat. El pez costero Scartichthys viridis habita las pozas bajas del intermareal a lo largo de la costa chilena. Debido a que el agua de mar se renueva en cada ciclo de marea en las pozas bajas, esta zona está caracterizada por una baja variación térmica y abundante alimento entre localidades. Nosotros evaluamos si las condiciones térmicas y la

  7. Variable collimator

    International Nuclear Information System (INIS)

    Richey, J.B.; McBride, T.R.; Covic, J.

    1979-01-01

    This invention describes an automatic variable collimator which controls the width and thickness of X-ray beams in X-ray diagnostic medical equipment, and which is particularly adapted for use with computerized axial tomographic scanners. A two-part collimator is provided which shapes an X-ray beam both prior to its entering an object subject to radiographic analysis and after the attenuated beam has passed through the object. Interposed between a source of radiation and the object subject to radiographic analysis is a first or source collimator. The source collimator causes the X-ray beam emitted by the source of radiation to be split into a plurality of generally rectangular shaped beams. Disposed within the source collimator is a movable aperture plate which may be used to selectively vary the thickness of the plurality of generally rectangular shaped beams transmitted through the source collimator. A second or receiver collimator is interposed between the object subject to radiographic analysis and a series of radiation detectors. The receiver collimator is disposed to receive the attenuated X-ray beams passing through the object subject to radiographic analysis. Located within the receiver collimator are a plurality of movable aperture plates adapted to be displaced relative to a plurality of fixed aperture plates for the purpose of varying the width and thickness of the attenuated X-ray beams transmitted through the object subject to radiographic analysis. The movable aperture plates of the source and receiver collimators are automatically controlled by circuitry which is provided to allow remote operation of the movable aperture plates

  8. Climate variability and change

    International Nuclear Information System (INIS)

    Manton, M.

    2006-01-01

    When Australia's climate should not be definite barrier to the population reaching 30 million by 2050, it is recognised that our climate has limited the development of the nation over the past 200 years. Indeed in 1911, based on a comparison of the climate and development between the US and Australia. Griffith Taylor predicted that Australia's population would be 19 million at the end of the 20th century, which is a pretty good 90-year forecast. The climate constraint is not only due to much of the country being semi-arid with an annual rainfall below 400 millimetres, but also due to the large year-to-year variability of rainfall across the country

  9. Associations among the Five Components within COSO Internal Control-Integrated Framework as the Underpinning of Quality Corporate Governance

    Directory of Open Access Journals (Sweden)

    Kirsten Rae

    2017-03-01

    Full Text Available This paper examines the associations among COSO components and how they affect the monitoring function of organisations. Five components of an effective internal control system are described using the framework designed by COSO (1992 and have been selected because they have been identified as underpinning quality corporate governance. Structural equation modelling (SEM was used first to run confirmatory factor analysis to determine the measurement models for the five COSO components. The COSO report (1992 described the internal control framework as a multidirectional iterative and situational (contingent process. The primary structural model was designed to reflect the one-way directional associations in the model described and shown in Exhibit 1 within the COSO report (1992. SEM analyses were conducted to test the hypotheses. Additional secondary SEM analyses were undertaken to investigate the reciprocal associations suggested in the COSO report (1992. Findings from the primary SEM analysis provide partial support for associations among the COSO components and enhanced monitoring quality that leads to good corporate governance. The results show that control environment is associated with three dimensions of information and communication (information accuracy, information openness, communication and learning. Additionally, two dimensions of information and communication (communication and learning and information feedback flow were found to be associated with risk assessment. An indirect association is supported by the results between control environment and risk assessment through the associations among three dimensions of information and communication (information accuracy, information openness and information feedback flow. Risk assessment is associated with control activities, which is subsequently associated with monitoring. The results of the additional secondary SEM analyses supported the reciprocal associations among risk assessment

  10. A draft of guidance from the scientific Research Programme GEOTECHNOLOGIEN to underpin the implementation of the CCS Directive in Germany

    Science.gov (United States)

    Streibel, Martin; Schoebel, Birgit

    2015-04-01

    In 2004 the Federal Ministry of Education and Research of Germany launched the programme GEOTECHNOLOGIEN with one key aspect being the development of technologies for sustainable storage of carbon dioxide in geological formations. Within this research field more than 30 projects in three consecutive programme phases have been funded up to the end of 2014. In order to benefit from the gathered knowledge and use the experiences for the policy/law making process the umbrella project AUGE has been launched in October 2012 with a life time of three years. The aim of the project is to review and compile all results of projects funded during the three phases to underpin the appendices of the German transposition of the EC Directive 2009/31/EC the "Carbon Dioxide Storage Law" (KSpG). The results of the projects have been structured along the lines of the two appendices of the KSpG which are similar to the ones of the EC Directive. The detailed structure follows the CSA Z741, Canada's first CCS standard for the geological storage of carbon emissions deep underground. This document also serves as the draft version for the ISO Technical Committee 265 "Carbon dioxide capture, transportation, and geological storage". From the risk management perspective, according to ISO 31000, most of the research performed in the above mentioned scientific programme dealt with contextual background of geological CO2 storage asking the question which physical, chemical and biological interactions of CO2 are most important to understand to evaluate if CO2 storage in general is feasible. This lead to risk identification, risk analysis and risk evaluation. Major topics of the scientific programme were • site characterisation with development and optimisation of laboratory procedures and implementation amongst other activities at the pilot site at Ketzin; • optimization of seismic procedures for site characterisation and the detection of injected CO2; • physical, chemical and microbiological

  11. Intergenomic comparisons highlight modularity of the denitrification pathway and underpin the importance of community structure for N2O emissions.

    Directory of Open Access Journals (Sweden)

    Daniel R H Graf

    underpinning the importance of community structure for N2O emissions.

  12. Legitimacy of forest rights: The underpinnings of the forest tenure reform in the protected areas of petén, Guatemala

    Directory of Open Access Journals (Sweden)

    Iliana Monterroso

    2012-01-01

    Full Text Available In recent decades, forests across the world have undergone a significant process of recognition and transference of tenure rights to local communities or individuals, referred to here as forest tenure reforms. Among developing regions, Latin America has seen the most important recognition and transference of these tenure rights to forest dwelling and forest dependent communities. This paper examines the process in Guatemala, where the state has recognised and transferred rights to organised local groups-establishing a community concession system in the multiple use zone of the Maya Biosphere Reserve. We analyse the evolution of claims over forest uses, and focus on the legitimacy elements underpinning the process of a claim becoming a right. The results indicate that in order to sustain this forest tenure reform process over time, it is important to understand how tenure arrangements are transferred and distributed among rights-receivers, and how this process is influenced by the elements that underpin legitimation as well as those that define authority. Understanding the underpinnings of the legitimacy behind forest tenure reforms is central to identifying ways in which these processes can work, and also becomes important for developing more sound policy frameworks that fill gaps and resolve incongruence in governmental systems for forest management.

  13. Mechanisms Underpinning Degradation of Protective Oxides and Thermal Barrier Coatings in High Hydrogen Content (HHC) - Fueled Turbines

    Energy Technology Data Exchange (ETDEWEB)

    Mumm, Daniel

    2013-08-31

    The overarching goal of this research program has been to evaluate the potential impacts of coal-derived syngas and high-hydrogen content fuels on the degradation of turbine hot-section components through attack of protective oxides and thermal barrier coatings. The primary focus of this research program has been to explore mechanisms underpinning the observed degradation processes, and connections to the combustion environments and characteristic non-combustible constituents. Based on the mechanistic understanding of how these emerging fuel streams affect materials degradation, the ultimate goal of the program is to advance the goals of the Advanced Turbine Program by developing materials design protocols leading to turbine hot-section components with improved resistance to service lifetime degradation under advanced fuels exposures. This research program has been focused on studying how: (1) differing combustion environments – relative to traditional natural gas fired systems – affect both the growth rate of thermally grown oxide (TGO) layers and the stability of these oxides and of protective thermal barrier coatings (TBCs); and (2) how low levels of fuel impurities and characteristic non-combustibles interact with surface oxides, for instance through the development of molten deposits that lead to hot corrosion of protective TBC coatings. The overall program has been comprised of six inter-related themes, each comprising a research thrust over the program period, including: (i) evaluating the role of syngas and high hydrogen content (HHC) combustion environments in modifying component surface temperatures, heat transfer to the TBC coatings, and thermal gradients within these coatings; (ii) understanding the instability of TBC coatings in the syngas and high hydrogen environment with regards to decomposition, phase changes and sintering; (iii) characterizing ash deposition, molten phase development and infiltration, and associated corrosive

  14. Twitter as a Potential Disaster Risk Reduction Tool. Part III: Evaluating Variables that Promoted Regional Twitter Use for At-risk Populations During the 2013 Hattiesburg F4 Tornado.

    Science.gov (United States)

    Cooper, Guy Paul; Yeager, Violet; Burkle, Frederick M; Subbarao, Italo

    2015-06-29

    Study goals attempt to identify the variables most commonly associated with successful tweeted messages and determine which variables have the most influence in promoting exponential dissemination of information (viral spreading of the message) and trending (becoming popular) in the given disaster affected region. Part II describes the detailed extraction and triangulation filtration methodological approach to acquiring twitter data for the 2013 Hattiesburg Tornado. The data was then divided into two 48 hour windows before and after the tornado impact with a 2 hour pre-tornado buffer to capture tweets just prior to impact. Criteria-based analysis was completed for Tweets and users. The top 100 pre-Tornado and post-Tornado retweeted users were compared to establish the variability among the top retweeted users during the 4 day span.  Pre-Tornado variables that were correlated to higher retweeted rates include total user tweets (0.324), and total times message retweeted (0.530).  Post-Tornado variables that were correlated to higher retweeted rates include total hashtags in a retweet (0.538) and hashtags #Tornado (0.378) and #Hattiesburg (0.254). Overall hashtags usage significantly increased during the storm. Pre-storm there were 5,763 tweets with a hashtag and post-storm there was 13,598 using hashtags. Twitter's unique features allow it to be considered a unique social media tool applicable for emergency managers and public health officials for rapid and accurate two way communication.  Additionally, understanding how variables can be properly manipulated plays a key role in understanding how to use this social media platform for effective, accurate, and rapid mass information communication.

  15. Analysis of Population Dynamics in World Economy

    OpenAIRE

    Martin, Gress

    2011-01-01

    Population dynamics is an important topic in current world economy. The size and growth of population have an impact on economic growth and development of individual countries and vice versa, economic development influences demographic variables in a country. The aim of the article is to analyze historical development of world population, population stock change and relations between population stock change and economic development.

  16. Impact of Population Aging on Asia's Future Growth

    OpenAIRE

    Park, Donghyun; Shin, Kwanho

    2011-01-01

    First, the expert contributors argue, Asia must find ways to sustain rapid economic growth in the face of less favorable demographics, which implies slower growth of the workforce. Second, they contend, Asia must find ways to deliver affordable, adequate, and sustainable old-age economic security for its growing elderly population. Underpinned by rigorous analysis, a wide range of concrete policy options for sustaining economic growth while delivering economic security for the elderly are the...

  17. The processes underpinning reductions in disability among people with chronic neck pain. A preliminary comparison between two distinct types of physiotherapy intervention.

    Science.gov (United States)

    Thompson, Dave P; Woby, Steve R

    2018-04-01

    To establish whether different processes underpin changes in disability in people with neck pain who underwent two types of active physiotherapy intervention. This study was a sub-analysis of a randomized controlled trial assessing whether the addition of Interactive Behavioral Modification Therapy (a cognitively informed physiotherapy treatment) to a Progressive Neck Exercise Program improved outcome in patients with chronic neck pain. Regression analyses were performed to determine the extent to which demographics, changes in pain, and changes in certain cognitive factors were related to changes in disability. In the progressive neck exercise group, changes in levels of pain intensity were the only factor significantly related to change in disability, explaining 33% of the variance. In the interactive behavioral modification therapy group, changes in pain intensity, and catastrophizing together explained 54% of the variance in change in disability. Only changes in catastrophizing displayed a significant β value in the final model. Different processes appear to underpin changes in disability in patients undergoing cognitively informed physiotherapy to those undergoing a primarily exercise-based approach. Implications for rehabilitation Certain cognitive factors are known to be related to levels of disability in patients with chronic neck pain Specifically targeting these factors results in more patients making a clinically meaningful reduction in disability Different processes appear to underpin reductions in disability when people with neck pain are treated with cognitively informed physiotherapy to when treated with exercise alone, which may account for why more patients improve when treated in this manner. Reductions in catastrophizing appear to be particularly important and efforts should be made to assess and treat catastrophic thoughts in people with chronic neck pain.

  18. Short-term variability and nocturnal decline in ambulatory blood pressure in normotension, white-coat hypertension, masked hypertension and sustained hypertension: a population-based study of older individuals in Spain.

    Science.gov (United States)

    Gijón-Conde, Teresa; Graciani, Auxiliadora; López-García, Esther; Guallar-Castillón, Pilar; García-Esquinas, Esther; Rodríguez-Artalejo, Fernando; Banegas, José R

    2017-06-01