Snail phenotypic variation and stress proteins: do different heat response strategies contribute to Waddington's widget in field populations?

PubMed

Köhler, Heinz-R; Lazzara, Raimondo; Dittbrenner, Nils; Capowiez, Yvan; Mazzia, Christophe; Triebskorn, Rita

2009-03-15

On the basis of studies with laboratory strains of Drosophila and Arabidopsis, it has been hypothesized that potential buffers to the expression of phenotypic morphological variation, such as Hsp90 and possibly Hsp70, represent important components of Waddington's widget, which may confer capacitive evolution. As studies on field populations of living organisms to test this hypothesis are lacking, we tested whether a heat response strategy involving high stress protein levels is associated with low morphological variation and vice versa, using four natural populations of Mediterranean pulmonate snails. In response to 8 hr of elevated temperatures, a population of Xeropicta derbentina with uniform shell pigmentation pattern showed remarkably high Hsp70 but low Hsp90 levels. In contrast, a highly variable population of Cernuella virgata kept both Hsp90 and Hsp70 levels low when held at diverse though environmentally relevant temperatures. Two other populations (Theba pisana and another X. derbentina population) with intermediate variation in shell pigmentation pattern were also intermediate in inducing Hsp70, though Hsp90 was maintained at a low level. The observed correlation of stress protein levels and coloration pattern variation provide the first indirect evidence for an association of stress proteins with Waddington's widget under natural conditions.

Development of genetic diversity, differentiation and structure over 500 years in four ponderosa pine populations.

PubMed

Lesser, M R; Parchman, T L; Jackson, S T

2013-05-01

Population history plays an important role in shaping contemporary levels of genetic variation and geographic structure. This is especially true in small, isolated range-margin populations, where effects of inbreeding, genetic drift and gene flow may be more pronounced than in large continuous populations. Effects of landscape fragmentation and isolation distance may have implications for persistence of range-margin populations if they are demographic sinks. We studied four small, disjunct populations of ponderosa pine over a 500-year period. We coupled demographic data obtained through dendroecological methods with microsatellite data to discern how and when contemporary levels of allelic diversity, among and within-population levels of differentiation, and geographic structure, arose. Alleles accumulated rapidly following initial colonization, demonstrating proportionally high levels of gene flow into the populations. At population sizes of approximately 100 individuals, allele accumulation saturated. Levels of genetic differentiation among populations (F(ST) and Jost's D(est)) and diversity within populations (F(IS)) remained stable through time. There was no evidence of geographic genetic structure at any time in the populations' history. Proportionally, high gene flow in the early stages of population growth resulted in rapid accumulation of alleles and quickly created relatively homogenous genetic patterns among populations. Our study demonstrates that contemporary levels of genetic diversity were formed quickly and early in population development. How contemporary genetic diversity accumulates over time is a key facet of understanding population growth and development. This is especially relevant given the extent and speed at which species ranges are predicted to shift in the coming century. © 2013 Blackwell Publishing Ltd.

Comparison of plasma levels of obesity-related biomarkers among Japanese populations in Tokyo, Japan, São Paulo, Brazil, and Hawaii, USA.

PubMed

Iwasaki, Motoki; Le Marchand, Loïc; Franke, Adrian A; Hamada, Gerson Shigeaki; Miyajima, Nelson Tomio; Sharma, Sangita; Yamaji, Taiki; Tsugane, Shoichiro

2016-01-01

Although Japanese in Japan and the USA are high-risk populations for colorectal cancer, the prevalence of obesity, one of the established risk factors for this disease, is low in these populations compared with other high-risk populations. To understand this inconsistency, we compared plasma obesity-related biomarkers in cross-sectional studies carried out in Tokyo, São Paulo, and Hawaii. We measured plasma levels of insulin-like growth factor-I (IGF-I), insulin-like growth factor-binding protein (IGFBP)-1, IGFBP-3, C-peptide, adiponectin, leptin, tumor necrosis factor-α, and interleukin-6 by immunoassay and total C-reactive protein, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglycerides using a clinical chemistry autoanalyzer. A total of 299 participants were included in the present analysis, comprising 142 Japanese in Tokyo, 79 Japanese Brazilians in São Paulo, and 78 Japanese Americans in Hawaii. We found significantly lower plasma levels of C-peptide and IGF-I in Japanese in Tokyo than in Japanese Americans, and lower levels of leptin and triglycerides and higher levels of adiponectin, IGFBP-3, and high-density lipoprotein cholesterol in Japanese in Tokyo than in the other two populations. We also observed a significantly higher plasma IGFBP-1 level in Japanese Brazilians, and lower plasma levels of total cholesterol and low-density lipoprotein in Japanese Americans than in the other two populations. We observed significant differences in obesity-related biomarkers between the three Japanese populations. If our results are confirmed, the risk of colorectal cancer predicted on the basis of these biomarkers would be lowest for Japanese in Tokyo, followed by Japanese Brazilians and Japanese Americans.

Comparison of plasma levels of obesity-related biomarkers among Japanese populations in Tokyo, Japan, São Paulo, Brazil, and Hawaii, USA

PubMed Central

Le Marchand, Loïc; Franke, Adrian A.; Hamada, Gerson Shigeaki; Miyajima, Nelson Tomio; Sharma, Sangita; Yamaji, Taiki; Tsugane, Shoichiro

2016-01-01

Although Japanese in Japan and the USA are high-risk populations for colorectal cancer, the prevalence of obesity, one of the established risk factors for this disease, is low in these populations compared with other high-risk populations. To understand this inconsistency, we compared plasma obesity-related biomarkers in cross-sectional studies carried out in Tokyo, São Paulo, and Hawaii. We measured plasma levels of insulin-like growth factor-I (IGF-I), insulin-like growth factor-binding protein (IGFBP)-1, IGFBP-3, C-peptide, adiponectin, leptin, tumor necrosis factor-α, and interleukin-6 by immunoassay and total C-reactive protein, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglycerides using a clinical chemistry autoanalyzer. A total of 299 participants were included in the present analysis, comprising 142 Japanese in Tokyo, 79 Japanese Brazilians in São Paulo, and 78 Japanese Americans in Hawaii. We found significantly lower plasma levels of C-peptide and IGF-I in Japanese in Tokyo than in Japanese Americans, and lower levels of leptin and triglycerides and higher levels of adiponectin, IGFBP-3, and high-density lipoprotein cholesterol in Japanese in Tokyo than in the other two populations. We also observed a significantly higher plasma IGFBP-1 level in Japanese Brazilians, and lower plasma levels of total cholesterol and low-density lipoprotein in Japanese Americans than in the other two populations. We observed significant differences in obesity-related biomarkers between the three Japanese populations. If our results are confirmed, the risk of colorectal cancer predicted on the basis of these biomarkers would be lowest for Japanese in Tokyo, followed by Japanese Brazilians and Japanese Americans. PMID:25714650

Association between unemployment, income, education level, population size and air pollution in Czech cities: evidence for environmental inequality? A pilot national scale analysis.

PubMed

Branis, Martin; Linhartova, Martina

2012-09-01

We analyzed differentials in exposure to SO(2), PM(10) and NO(2) among Czech urban populations categorized according to education level, unemployment rate, population size and average annual salary. Altogether 39 cities were included in the analysis. The principal component analysis revealed two factors explaining 72.8% of the data variability. The first factor explaining 44.7% of the data variability included SO(2), PM(10), low education level and high unemployment, documenting that inhabitants with unfavorable socioeconomic status mainly reside in smaller cities with higher concentration levels of combustion-related air pollutants. The second factor explaining 28.1% of the data variability included NO(2), high salary, high education level and large population, suggesting that large cities with residents with higher socioeconomic status are exposed to higher levels of traffic-related air pollution. We conclude that, after more than a decade of free-market economy, the Czech Republic, a former Soviet satellite with a centrally planned economy, displays signs of a certain kind of environmental inequality, since environmental hazards are unevenly distributed among the Czech urban populations. Copyright © 2012 Elsevier Ltd. All rights reserved.

Genetic variation and population structure of the mixed-mating cactus, Melocactus curvispinus (Cactaceae).

PubMed

Nassar, J M; Hamrick, J L; Fleming, T H

2001-07-01

Genetic diversity was measured in the mixed-mating cactus, Melocactus curvispinus, in Venezuela. Allozyme diversity was surveyed in 19 putative loci over 18 populations. Compared to other plant taxa, this cactus is rich in polymorphic loci (Ps=89.5%), with high numbers of alleles per polymorphic locus (APs=3.82), but moderate levels of heterozygosity (Hes=0.145). Substantial levels of inbreeding were detected across loci and populations at macrogeographic (FIS=0.348) and regional levels (FIS=0.194-0.402). Moderate levels of genetic differentiation among populations were detected at macrogeographical (FST=0.193) and regional (FST=0.084-0.187) scales, suggesting that gene flow is relatively restricted, but increases within regions without topographic barriers. The population genetic structure observed for this cactus was attributed to, at least, three factors: short-distance pollination and seed dispersal, the mixed-mating condition of the species, and genetic drift. High genetic identities between populations (I=0.942) supported the conspecific nature of all populations surveyed. The levels and patterns of genetic structure observed for M. curvispinus were consistent with its mating system and gene dispersal mechanisms.

Selection of high heterozygosity popcorn varieties in Brazil based on SSR markers.

PubMed

Eloi, I B O; Mangolin, C A; Scapim, C A; Gonçalves, C S; Machado, M F P S

2012-07-19

We analyzed genetic structure and diversity among eight populations of popcorn, using SSR loci as genetic markers. Our objectives were to select SSR loci that could be used to estimate genetic diversity within popcorn populations, and to analyze the genetic structure of promising populations with high levels of heterozygosity that could be used in breeding programs. Fifty-seven alleles (3.7 alleles per locus) were detected; the highest effective number of alleles (4.21) and the highest gene diversity (0.763) were found for the Umc2226 locus. A very high level of population differentiation was found (F(ST) = 0.3664), with F(ST) for each locus ranging from 0.1029 (Umc1664) to 0.6010 (Umc2350). This analysis allowed us to identify SSR loci with high levels of heterozygosity and heterozygous varieties, which could be selected for production of inbred lines and for developing new cultivars.

Population-dependent effects of ocean acidification.

PubMed

Wood, Hannah L; Sundell, Kristina; Almroth, Bethanie Carney; Sköld, Helén Nilsson; Eriksson, Susanne P

2016-04-13

Elevated carbon dioxide levels and the resultant ocean acidification (OA) are changing the abiotic conditions of the oceans at a greater rate than ever before and placing pressure on marine species. Understanding the response of marine fauna to this change is critical for understanding the effects of OA. Population-level variation in OA tolerance is highly relevant and important in the determination of ecosystem resilience and persistence, but has received little focus to date. In this study, whether OA has the same biological consequences in high-salinity-acclimated population versus a low-salinity-acclimated population of the same species was investigated in the marine isopod Idotea balthica.The populations were found to have physiologically different responses to OA. While survival rate was similar between the two study populations at a future CO2 level of 1000 ppm, and both populations showed increased oxidative stress, the metabolic rate and osmoregulatory activity differed significantly between the two populations. The results of this study demonstrate that the physiological response to OA of populations from different salinities can vary. Population-level variation and the environment provenance of individuals used in OA experiments should be taken into account for the evaluation and prediction of climate change effects. © 2016 The Author(s).

Population-dependent effects of ocean acidification

PubMed Central

Wood, Hannah L.; Sundell, Kristina; Almroth, Bethanie Carney; Sköld, Helén Nilsson; Eriksson, Susanne P.

2016-01-01

Elevated carbon dioxide levels and the resultant ocean acidification (OA) are changing the abiotic conditions of the oceans at a greater rate than ever before and placing pressure on marine species. Understanding the response of marine fauna to this change is critical for understanding the effects of OA. Population-level variation in OA tolerance is highly relevant and important in the determination of ecosystem resilience and persistence, but has received little focus to date. In this study, whether OA has the same biological consequences in high-salinity-acclimated population versus a low-salinity-acclimated population of the same species was investigated in the marine isopod Idotea balthica. The populations were found to have physiologically different responses to OA. While survival rate was similar between the two study populations at a future CO2 level of 1000 ppm, and both populations showed increased oxidative stress, the metabolic rate and osmoregulatory activity differed significantly between the two populations. The results of this study demonstrate that the physiological response to OA of populations from different salinities can vary. Population-level variation and the environment provenance of individuals used in OA experiments should be taken into account for the evaluation and prediction of climate change effects. PMID:27053741

Phenotypic diversity, population structure and stress protein-based capacitoring in populations of Xeropicta derbentina, a heat-tolerant land snail species.

PubMed

Di Lellis, Maddalena A; Sereda, Sergej; Geißler, Anna; Picot, Adrien; Arnold, Petra; Lang, Stefanie; Troschinski, Sandra; Dieterich, Andreas; Hauffe, Torsten; Capowiez, Yvan; Mazzia, Christophe; Knigge, Thomas; Monsinjon, Tiphaine; Krais, Stefanie; Wilke, Thomas; Triebskorn, Rita; Köhler, Heinz-R

2014-11-01

The shell colour of many pulmonate land snail species is highly diverse. Besides a genetic basis, environmentally triggered epigenetic mechanisms including stress proteins as evolutionary capacitors are thought to influence such phenotypic diversity. In this study, we investigated the relationship of stress protein (Hsp70) levels with temperature stress tolerance, population structure and phenotypic diversity within and among different populations of a xerophilic Mediterranean snail species (Xeropicta derbentina). Hsp70 levels varied considerably among populations, and were significantly associated with shell colour diversity: individuals in populations exhibiting low diversity expressed higher Hsp70 levels both constitutively and under heat stress than those of phenotypically diverse populations. In contrast, population structure (cytochrome c oxidase subunit I gene) did not correlate with phenotypic diversity. However, genetic parameters (both within and among population differences) were able to explain variation in Hsp70 induction at elevated but non-pathologic temperatures. Our observation that (1) population structure had a high explanatory potential for Hsp70 induction and that (2) Hsp70 levels, in turn, correlated with phenotypic diversity while (3) population structure and phenotypic diversity failed to correlate provides empirical evidence for Hsp70 to act as a mediator between genotypic variation and phenotype and thus for chaperone-driven evolutionary capacitance in natural populations.

Dasymetric high resolution population distribution estimates for improved decision making, with a case study of sea-level rise vulnerability in Boca Raton, Florida

NASA Astrophysics Data System (ADS)

Ziegler, Hannes Moritz

Planners and managers often rely on coarse population distribution data from the census for addressing various social, economic, and environmental problems. In the analysis of physical vulnerabilities to sea-level rise, census units such as blocks or block groups are coarse relative to the required decision-making application. This study explores the benefits offered from integrating image classification and dasymetric mapping at the household level to provide detailed small area population estimates at the scale of residential buildings. In a case study of Boca Raton, FL, a sea-level rise inundation grid based on mapping methods by NOAA is overlaid on the highly detailed population distribution data to identify vulnerable residences and estimate population displacement. The enhanced spatial detail offered through this method has the potential to better guide targeted strategies for future development, mitigation, and adaptation efforts.

Genetic diversity and population structure of Vriesea reitzii (Bromeliaceae), a species from the Southern Brazilian Highlands

PubMed Central

Soares, Luis Eduardo; Goetze, Márcia; Zanella, Camila M.; Bered, Fernanda

2018-01-01

Abstract The Southern Brazilian Highlands are composed by a mosaic of Mixed Ombrophilous Forest (MOF) and grassland formations, an interesting landscape for the study of population structure. We analyzed the genetic diversity within and among populations of the MOF-endemic bromeliad Vriesea reitzii by genotyping seven nuclear microsatellite loci in 187 individuals from six populations. We characterized levels of genetic diversity and assessed the genetic structure among populations. Vriesea reitzii populations showed high levels of genetic variation (number of alleles 28 - 43, allelic richness 3.589 - 5.531) and moderate levels of genetic differentiation (F ST = 0.123, R ST = 0.096). The high levels of genetic diversity may be explained by species life-history traits, such as habit and mating system. The moderate structure may be a product of the combination of ancient and contemporary gene flow, resulting from the expansion of the forest in the Holocene, and/or due to facilitated dispersal mediated by the MOF’s mosaic landscape. The genetic results indicated no imminent threat to this bromeliad. However, the species is highly associated with the MOF, putting landscape conservation at the center of conservation efforts for the species’ maintenance. PMID:29583153

Population genetics of the understory fishtail palm Chamaedorea ernesti-augusti in Belize: high genetic connectivity with local differentiation

PubMed Central

Cibrián-Jaramillo, Angélica; Bacon, Christine D; Garwood, Nancy C; Bateman, Richard M; Thomas, Meredith M; Russell, Steve; Bailey, C Donovan; Hahn, William J; Bridgewater, Samuel GM; DeSalle, Rob

2009-01-01

Background Developing a greater understanding of population genetic structure in lowland tropical plant species is highly relevant to our knowledge of increasingly fragmented forests and to the conservation of threatened species. Specific studies are particularly needed for taxa whose population dynamics are further impacted by human harvesting practices. One such case is the fishtail or xaté palm (Chamaedorea ernesti-augusti) of Central America, whose wild-collected leaves are becoming progressively more important to the global ornamental industry. We use microsatellite markers to describe the population genetics of this species in Belize and test the effects of climate change and deforestation on its recent and historical effective population size. Results We found high levels of inbreeding coupled with moderate or high allelic diversity within populations. Overall high gene flow was observed, with a north and south gradient and ongoing differentiation at smaller spatial scales. Immigration rates among populations were more difficult to discern, with minimal evidence for isolation by distance. We infer a tenfold reduction in effective population size ca. 10,000 years ago, but fail to detect changes attributable to Mayan or contemporary deforestation. Conclusion Populations of C. ernesti-augusti are genetically heterogeneous demes at a local spatial scale, but are widely connected at a regional level in Belize. We suggest that the inferred patterns in population genetic structure are the result of the colonization of this species into Belize following expansion of humid forests in combination with demographic and mating patterns. Within populations, we hypothesize that low aggregated population density over large areas, short distance pollen dispersal via thrips, low adult survival, and low fruiting combined with early flowering may contribute towards local inbreeding via genetic drift. Relatively high levels of regional connectivity are likely the result of animal-mediated long-distance seed dispersal. The greatest present threat to the species is the potential onset of inbreeding depression as the result of increased human harvesting activities. Future genetic studies in understory palms should focus on both fine-scale and landscape-level genetic structure. PMID:19818141

Effects of population density on corticosterone levels of prairie voles in the field

PubMed Central

Blondel, Dimitri V.; Wallace, Gerard N.; Calderone, Stefanie; Gorinshteyn, Marija; St. Mary, Colette M.; Phelps, Steven M.

2015-01-01

High population density is often associated with increased levels of stress-related hormones, such as corticosterone (CORT). Prairie voles (Microtus ochrogaster) are a socially monogamous species known for their large population density fluctuations in the wild. Although CORT influences the social behavior of prairie voles in the lab, the effect of population density on CORT has not previously been quantified in this species in the field. We validated a non-invasive hormone assay for measuring CORT metabolites in prairie vole feces. We then used semi-natural enclosures to experimentally manipulate population density, and measured density effects on male space use and fecal CORT levels. Our enclosures generated patterns of space use and social interaction that were consistent with previous prairie vole field studies. Contrary to the positive relationship between CORT and density typical of other taxa, we found that lower population densities (80 animals/ha) produced higher fecal CORT than high densities (240/ha). Combined with prior work in the lab and field, the data suggest that high prairie vole population densities indicate favorable environments, perhaps through reduced predation risk. Lastly, we found that field animals had lower fecal CORT levels than laboratory-living animals. The data emphasize the usefulness of prairie voles as models for integrating ecological, evolutionary and mechanistic questions in social behavior. PMID:26342968

Molecular analysis of red maple (Acer rubrum) populations from a reclaimed mining region in Northern Ontario (Canada): soil metal accumulation and translocation in plants.

PubMed

Kalubi, K N; Mehes-Smith, M; Narendrula, R; Michael, P; Omri, A

2015-04-01

Red maple (Acer rubrum) species is one of the most widespread deciduous (hardwood) trees of eastern North America. It is among the dominant tree species in the Northern Ontario after land reclamation. To date, the effects of heavy metal contamination from the mining activities on terrestrial ecosystems are not well understood. The main objectives of the present study are (1) to determine the level of phytoavailable metal in soil and accumulation in A. rubrum, and (2) to compare the levels of genetic variation among and within A. rubrum populations from areas with different metal contents in a Northern Ontario region. The total heavy metal levels were found to be high but the availability of these metals were much lower. We found that red maple does not accumulate heavy metals in their leaves as other hardwood species. The translocation factors were 0.05, 0.21, 0.38, 0.90, and 2.8 for Cu, Ni, Fe, Zn, and Mg, respectively. The levels of genetic variation in red maple populations from reclaimed lands in Northern Ontario were moderate to high since the percentage of polymorphic loci varied between 51 and 67%. The mean values for observed number of alleles (Na), effective number of alleles (Ne), Nei's gene diversity (h), and Shannon's information index (I) were 1.60, 1.24, 0.15 and 0.24, respectively. The population differentiation (GST) among the fragmented populations was high (0.28) despite a high level of gene flow (Nm = 1.28). Nevertheless, all the populations within the targeted region were genetically closely related. A specific ISSR marker that was identified in all the samples from the reference sites was absent in most samples from metal contaminated. This specific band was cloned and sequenced. Overall, the present study confirms that red maple populations in Northern Ontario are genetically sustainable despite the high level of total metal content in soil.

Comparison of mitochondrial DNA control region sequence and microsatellite DNA analyses in estimating population structure and gene flow rates in Atlantic sturgeon Acipenser oxyrinchus

USGS Publications Warehouse

Wirgin, I.; Waldman, J.; Stabile, J.; Lubinski, B.; King, T.

2002-01-01

Atlantic sturgeon Acipenser oxyrinchus is large, long-lived, and anadromous with subspecies distributed along the Atlantic (A. oxyrinchus oxyrinchus) and Gulf of Mexico (A. o. desotoi) coasts of North America. Although it is not certain if extirpation of some population units has occurred, because of anthropogenic influences abundances of all populations are low compared with historical levels. Informed management of A. oxyrinchus demands a detailed knowledge of its population structure, levels of genetic diversity, and likelihood to home to natal rivers. We compared the use of mitochondrial DNA (mtDNA) control region sequence and microsatellite nuclear DNA (nDNA) analyses in identifying the stock structure and homing fidelity of Atlantic and Gulf coast populations of A. oxyrinchus. The approaches were concordant in that they revealed moderate to high levels of genetic diversity and suggested that populations of Atlantic sturgeon are highly structured. At least six genetically distinct management units were detected using the two approaches among the rivers surveyed. Mitochondrial DNA sequences revealed a significant cline in haplotype diversity along the Atlantic coast with monomorphism observed in Canadian populations. High levels of nDNA diversity were also observed among populations along the Atlantic coast, including the two Canadian populations, probably resulting from the more rapid rate of mutational and evolutionary change at microsatellite loci. Estimates of gene flow among populations were similar between both approaches with the exception that because of mtDNA monomorphism in Canadian populations, gene flow estimates between them were unobtainable. Analyses of both genomes provided high resolution and confidence in characterizing the population structure of Atlantic sturgeon. Microsatellite analysis was particularly informative in delineating population structure in rivers that were recently glaciated and may prove diagnostic in rivers that are geographically proximal along the south Atlantic coast of the US.

Beyond the Coral Triangle: high genetic diversity and near panmixia in Singapore's populations of the broadcast spawning sea star Protoreaster nodosus.

PubMed

Tay, Y C; Chng, M W P; Sew, W W G; Rheindt, F E; Tun, K P P; Meier, R

2016-08-01

The Coral Triangle is widely considered the most important centre of marine biodiversity in Asia while areas on its periphery such as the South China Sea, have received much less interest. Here, we demonstrate that a small population of the knobbly sea star Protoreaster nodosus in Singapore has similarly high levels of genetic diversity as comparable Indonesian populations from the Coral Triangle. The high genetic diversity of this population is remarkable because it is maintained despite decades of continued anthropogenic disturbance. We postulate that it is probably due to broadcast spawning which is likely to maintain high levels of population connectivity. To test this, we analysed 6140 genome-wide single nucleotide polymorphism (SNP) loci for Singapore's populations and demonstrate a pattern of near panmixia. We here document a second case of high genetic diversity and low genetic structure for a broadcast spawner in Singapore, which suggests that such species have high resilience against anthropogenic disturbances. The study demonstrates the feasibility and power of using genome-wide SNPs for connectivity studies of marine invertebrates without a sequenced genome.

Heterogeneity of chemokine cell-surface receptor expression in triple-negative breast cancer

PubMed Central

Norton, Kerri-Ann; Popel, Aleksander S; Pandey, Niranjan B

2015-01-01

Introduction: Tumor heterogeneity is a well-established concept in cancer research. In this paper, we examine an additional type of tumor cell heterogeneity - tumor cell-surface receptor heterogeneity. Methods: We use flow cytometry to measure the frequency and numbers of cell-surface receptors on triple negative breast cancer cell lines. Results: We find two distinct populations of human triple-negative breast cancer cells MDA-MB-231 when they are grown in culture, one with low surface levels of various chemokine receptors and a second with much higher levels. The population with high surface levels of these receptors is increased in the more metastatic MDA-MB-231-luc-d3h2ln cell line. Conclusion: We hypothesize that this high cell-surface receptor population is involved in metastasis. We find that the receptor high populations can be modulated by tumor conditioned media and IL6 treatment indicating that the tumor microenvironment is important for the maintenance and sizes of these populations. PMID:26101698

Phylogeographic reconstruction of a bacterial species with high levels of lateral gene transfer

USGS Publications Warehouse

Pearson, T.; Giffard, P.; Beckstrom-Sternberg, S.; Auerbach, R.; Hornstra, H.; Tuanyok, A.; Price, E.P.; Glass, M.B.; Leadem, B.; Beckstrom-Sternberg, J. S.; Allan, G.J.; Foster, J.T.; Wagner, D.M.; Okinaka, R.T.; Sim, S.H.; Pearson, O.; Wu, Z.; Chang, J.; Kaul, R.; Hoffmaster, A.R.; Brettin, T.S.; Robison, R.A.; Mayo, M.; Gee, J.E.; Tan, P.; Currie, B.J.; Keim, P.

2009-01-01

Background: Phylogeographic reconstruction of some bacterial populations is hindered by low diversity coupled with high levels of lateral gene transfer. A comparison of recombination levels and diversity at seven housekeeping genes for eleven bacterial species, most of which are commonly cited as having high levels of lateral gene transfer shows that the relative contributions of homologous recombination versus mutation for Burkholderia pseudomallei is over two times higher than for Streptococcus pneumoniae and is thus the highest value yet reported in bacteria. Despite the potential for homologous recombination to increase diversity, B. pseudomallei exhibits a relative lack of diversity at these loci. In these situations, whole genome genotyping of orthologous shared single nucleotide polymorphism loci, discovered using next generation sequencing technologies, can provide very large data sets capable of estimating core phylogenetic relationships. We compared and searched 43 whole genome sequences of B. pseudomallei and its closest relatives for single nucleotide polymorphisms in orthologous shared regions to use in phylogenetic reconstruction. Results: Bayesian phylogenetic analyses of >14,000 single nucleotide polymorphisms yielded completely resolved trees for these 43 strains with high levels of statistical support. These results enable a better understanding of a separate analysis of population differentiation among >1,700 B. pseudomallei isolates as defined by sequence data from seven housekeeping genes. We analyzed this larger data set for population structure and allele sharing that can be attributed to lateral gene transfer. Our results suggest that despite an almost panmictic population, we can detect two distinct populations of B. pseudomallei that conform to biogeographic patterns found in many plant and animal species. That is, separation along Wallace's Line, a biogeographic boundary between Southeast Asia and Australia. Conclusion: We describe an Australian origin for B. pseudomallei, characterized by a single introduction event into Southeast Asia during a recent glacial period, and variable levels of lateral gene transfer within populations. These patterns provide insights into mechanisms of genetic diversification in B. pseudomallei and its closest relatives, and provide a framework for integrating the traditionally separate fields of population genetics and phylogenetics for other bacterial species with high levels of lateral gene transfer. ?? 2009 Pearson et al; licensee BioMed Central Ltd.

Multiple populations of artemisinin-resistant Plasmodium falciparum in Cambodia

PubMed Central

Miotto, Olivo; Almagro-Garcia, Jacob; Manske, Magnus; MacInnis, Bronwyn; Campino, Susana; Rockett, Kirk A; Amaratunga, Chanaki; Lim, Pharath; Suon, Seila; Sreng, Sokunthea; Anderson, Jennifer M; Duong, Socheat; Nguon, Chea; Chuor, Char Meng; Saunders, David; Se, Youry; Lon, Chantap; Fukuda, Mark M; Amenga-Etego, Lucas; Hodgson, Abraham VO; Asoala, Victor; Imwong, Mallika; Takala-Harrison, Shannon; Nosten, Francois; Su, Xin-zhuan; Ringwald, Pascal; Ariey, Frédéric; Dolecek, Christiane; Hien, Tran Tinh; Boni, Maciej F; Thai, Cao Quang; Amambua-Ngwa, Alfred; Conway, David J; Djimdé, Abdoulaye A; Doumbo, Ogobara K; Zongo, Issaka; Ouedraogo, Jean-Bosco; Alcock, Daniel; Drury, Eleanor; Auburn, Sarah; Koch, Oliver; Sanders, Mandy; Hubbart, Christina; Maslen, Gareth; Ruano-Rubio, Valentin; Jyothi, Dushyanth; Miles, Alistair; O’Brien, John; Gamble, Chris; Oyola, Samuel O; Rayner, Julian C; Newbold, Chris I; Berriman, Matthew; Spencer, Chris CA; McVean, Gilean; Day, Nicholas P; White, Nicholas J; Bethell, Delia; Dondorp, Arjen M; Plowe, Christopher V; Fairhurst, Rick M; Kwiatkowski, Dominic P

2013-01-01

We describe an analysis of genome variation in 825 Plasmodium falciparum samples from Asia and Africa that reveals an unusual pattern of parasite population structure at the epicentre of artemisinin resistance in western Cambodia. Within this relatively small geographical area we have discovered several distinct but apparently sympatric parasite subpopulations with extremely high levels of genetic differentiation. Of particular interest are three subpopulations, all associated with clinical resistance to artemisinin, which have skewed allele frequency spectra and remarkably high levels of haplotype homozygosity, indicative of founder effects and recent population expansion. We provide a catalogue of SNPs that show high levels of differentiation in the artemisinin-resistant subpopulations, including codon variants in various transporter proteins and DNA mismatch repair proteins. These data provide a population genetic framework for investigating the biological origins of artemisinin resistance and for defining molecular markers to assist its elimination. PMID:23624527

The Financing of Higher Education in Kyrgyzstan

ERIC Educational Resources Information Center

Tiuliundieva, N.

2008-01-01

Traditionally, Kyrgyzstan, like other countries of the former Soviet Union, held a fairly high position from the standpoint of the population's average level of education. As of the beginning of period of transition, the level of education in Kyrgyzstan was relatively high. By 1991, the rate of literacy among the adult population was 97.7 percent.…

Use of generalized population ratios to obtain Fe XV line intensities and linewidths at high electron densities

NASA Technical Reports Server (NTRS)

Kastner, S. O.; Bhatia, A. K.

1980-01-01

A generalized method for obtaining individual level population ratios is used to obtain relative intensities of extreme ultraviolet Fe XV emission lines in the range 284-500 A, which are density dependent for electron densities in the tokamak regime or higher. Four lines in particular are found to attain quite high intensities in the high-density limit. The same calculation provides inelastic contributions to linewidths. The method connects level populations and level widths through total probabilities t(ij), related to 'taboo' probabilities of Markov chain theory. The t(ij) are here evaluated for a real atomic system, being therefore of potential interest to random-walk theorists who have been limited to idealized systems characterized by simplified transition schemes.

Use of generalized population ratios to obtain Fe XV line intensities and linewidths at high electron densities

NASA Astrophysics Data System (ADS)

Kastner, S. O.; Bhatia, A. K.

1980-08-01

A generalized method for obtaining individual level population ratios is used to obtain relative intensities of extreme ultraviolet Fe XV emission lines in the range 284-500 A, which are density dependent for electron densities in the tokamak regime or higher. Four lines in particular are found to attain quite high intensities in the high-density limit. The same calculation provides inelastic contributions to linewidths. The method connects level populations and level widths through total probabilities t(ij), related to 'taboo' probabilities of Markov chain theory. The t(ij) are here evaluated for a real atomic system, being therefore of potential interest to random-walk theorists who have been limited to idealized systems characterized by simplified transition schemes.

Fire structures pine serotiny at different scales.

PubMed

Hernández-Serrano, Ana; Verdú, Miguel; González-Martínez, Santiago C; Pausas, Juli G

2013-12-01

Serotiny (delayed seed release with the consequent accumulation of a canopy seedbank) confers fitness benefits in environments with crown-fire regimes. Thus, we predicted that serotiny level should be higher in populations recurrently subjected to crown-fires than in populations where crown-fires are rare. In addition, under a high frequency of fires, space and resources are recurrently available, permitting recruitment around each mother to follow the seed rain shadow. Thus, we also predicted spatial aggregation of serotiny within populations. We compared serotiny, considering both the proportion and the age of serotinous cones, in populations living in contrasting fire regimes for two iconic Mediterranean pine species (Pinus halepensis, P. pinaster). We framed our results by quantitatively comparing the strength of the fire-serotiny relationship with previous studies worldwide. For the two species, populations living under high crown-fire recurrence regimes had a higher serotiny level than those populations where the recurrence of crown-fires was low. For P. halepensis (the species with higher serotiny), populations in high fire recurrence regimes had higher fine-scale spatial aggregation of serotiny than those inhabiting low fire recurrence systems. The strength of the observed fire-serotiny relationship in P. halepensis is among the highest in published literature. Fire regime shapes serotiny level among populations, and in populations with high serotiny, recurrent fires maintain a significant spatial structure for this trait. Consequently, fire has long-term evolutionary implications at different scales, emphasizing its prominent role in shaping the ecology of pines.

Plasma folate levels and associated factors in women planning to become pregnant in a population with high prevalence of neural tube defects.

PubMed

Ma, Rui; Wang, Linlin; Jin, Lei; Li, Zhiwen; Ren, Aiguo

2017-07-17

Optimal blood folate levels of women before pregnancy are critical to the prevention of neural tube defects (NTDs). However, few studies have focused on blood folate levels of women planning to become pregnant. The aims of this study were to assess plasma folate levels in women who planned to become pregnant in a population with high prevalence of NTDs, to identify factors associated with plasma folate levels, and to evaluate the risk of NTDs at the population level. A total of 2065 women were enrolled at the time of premarital health check-up in two rural counties in northern China from November 2009 to December 2012. Fasting venous blood samples were collected and plasma folate concentrations were measured by microbiological method. The overall median of plasma folate was 10.5 nmol/L. 50% of the women had a plasma folate level below 10.5 nmol/L, a cutoff for megaloblastic anemia, and 88% below 18 nmol/L, a proposed optimal plasma folate level for the prevention of NTDs. Folic acid supplementation was the only factor to be associated with plasma folate concentrations, but only 1.9% of the women reported having taken folic acid supplements. A population risk of 29.3 NTD cases per 10,000 births was predicted. Women who planned to become pregnant had very low plasma folate in the population. Folic acid supplementation was the only factor to be associated with a high plasma folate concentration. High NTD risk would remain if women would get pregnant without having taken folic acid supplements. Birth Defects Research 109:1039-1047, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

The Relationship between 25 (OH) D Levels (Vitamin D) and Bone Mineral Density (BMD) in a Saudi Population in a Community-Based Setting.

PubMed

Alkhenizan, Abdullah; Mahmoud, Ahmed; Hussain, Aneela; Gabr, Alia; Alsoghayer, Suad; Eldali, Abdelmoneim

2017-01-01

Vitamin D deficiency has been linked to an increased risk of osteoporosis. Vitamin D deficiency has reached high levels in the Saudi population, but there is conflicting evidence both in the Saudi population, and worldwide, regarding the existence of a correlation between these low vitamin D levels and reduced BMD (bone mineral density), or osteoporosis. The objective of this study was primarily to determine whether there was a correlation between vitamin D deficiency and osteoporosis in the Saudi population. We aimed to investigate whether the high levels of vitamin D deficiency and insufficiency would translate to higher prevalence of osteoporosis, and whether there is a correlation between vitamin D levels and bone mineral density. This was a community based cross sectional study conducted in the Family Medicine Clinics at King Faisal Specialist Hospital and Research Centre in Riyadh, Saudi Arabia. Electronic records of 1723 patients were reviewed. Laboratory and radiology results were collected, including vitamin D levels, calcium levels, and bone mineral density scan results. Among the whole population, 61.5% had moderate to severe vitamin D deficiency with levels less than 50nmol/L. 9.1% of the population had osteoporosis, and 38.6% had osteopenia. Among the whole population, there was no significant correlation between spine or total femoral BMD and serum 25(OH) D. Vitamin D deficiency is prevalent in the Saudi population. However, no correlation has been found between vitamin D deficiency and reduced bone mineral density in any age group, in males or females, Saudis or Non-Saudis, in our population in Riyadh, Saudi Arabia.

Different level of population differentiation among human genes.

PubMed

Wu, Dong-Dong; Zhang, Ya-Ping

2011-01-14

During the colonization of the world, after dispersal out of African, modern humans encountered changeable environments and substantial phenotypic variations that involve diverse behaviors, lifestyles and cultures, were generated among the different modern human populations. Here, we study the level of population differentiation among different populations of human genes. Intriguingly, genes involved in osteoblast development were identified as being enriched with higher FST SNPs, a result consistent with the proposed role of the skeletal system in accounting for variation among human populations. Genes involved in the development of hair follicles, where hair is produced, were also found to have higher levels of population differentiation, consistent with hair morphology being a distinctive trait among human populations. Other genes that showed higher levels of population differentiation include those involved in pigmentation, spermatid, nervous system and organ development, and some metabolic pathways, but few involved with the immune system. Disease-related genes demonstrate excessive SNPs with lower levels of population differentiation, probably due to purifying selection. Surprisingly, we find that Mendelian-disease genes appear to have a significant excessive of SNPs with high levels of population differentiation, possibly because the incidence and susceptibility of these diseases show differences among populations. As expected, microRNA regulated genes show lower levels of population differentiation due to purifying selection. Our analysis demonstrates different level of population differentiation among human populations for different gene groups.

Postfire response and genetic diversity in Erica coccinea: connecting population dynamics and diversification in a biodiversity hotspot.

PubMed

Segarra-Moragues, José Gabriel; Ojeda, Fernando

2010-12-01

Understanding the processes of biological diversification is a central topic in evolutionary biology. The South African Cape fynbos, one of the major plant biodiversity hotspots out of the tropics, has prompted several hypotheses about the causes of generation and maintenance of biodiversity. Fire has been traditionally invoked as a key element to explain high levels of biodiversity in highly speciose fynbos taxa, such as the genus Erica. In this study, we have implemented a microevolutionary approach to elucidate how plant-response to fire may contribute to explain high levels of diversification in Erica. By using microsatellite markers, we investigated the genetic background of seeder (fire-sensitive) and resprouter (fire-resistant) populations of the fynbos species Erica coccinea. We found higher within-population genetic diversity and higher among-population differentiation in seeder populations and interpreted these higher levels of genetic diversification as a consequence of the comparatively shorter generation times and faster population turnover in the seeder form of this species. Considering that genetic divergence among populations may be seen as the initial step to speciation, the parallelism between these results and the pattern of biodiversity at the genus level offers stimulating insights into understanding causes of speciation of the genus Erica in the Cape fynbos. © 2010 The Author(s). Evolution© 2010 The Society for the Study of Evolution.

Behavioural and physiological effects of population density on domesticated Zebra Finches (Taeniopygia guttata) held in aviaries.

PubMed

Poot, Hanneke; ter Maat, Andries; Trost, Lisa; Schwabl, Ingrid; Jansen, René F; Gahr, Manfred

2012-02-01

Zebra Finches (Taeniopygia guttata) are highly social and monogamous birds that display relatively low levels of aggression and coordinate group life mainly by means of vocal communication. In the wild, small groups may congregate to larger flocks of up to 150-350 birds. Little is known, however, about possible effects of population density on development in captivity. Investigating density effects on physiology and behaviour might be helpful in identifying optimal group size, in order to optimise Zebra Finch wellbeing. A direct effect of population density on development and reproduction was found: birds in lower density conditions produced significantly more and larger (body mass, tarsus length) surviving offspring than birds in high density conditions. Furthermore, offspring in low density aviaries produced slightly longer song motifs and more different syllables than their tutors, whereas offspring in high density aviaries produced shorter motifs and a smaller or similar number of different syllables than their tutors. Aggression levels within the populations were low throughout the experiment, but the number of aggressive interactions was significantly higher in high density aviaries. Baseline corticosterone levels did not differ significantly between high- and low density aviaries for either adult or offspring birds. On day 15 post hatching, brood size and baseline corticosterone levels were positively correlated. On days 60 and 100 post hatching this correlation was no longer present. The results of this study prove that population density affects various aspects of Zebra Finch development, with birds living in low population density conditions having an advantage over those living under higher population density conditions. Copyright © 2011 Elsevier Inc. All rights reserved.

Chronic wasting disease drives population decline of white-tailed deer

USGS Publications Warehouse

Edmunds, David; Kauffman, Matthew J.; Schumaker, Brant; Lindzey, Frederick G.; Cook, Walter; Kreeger, Terry J.; Grogan, Ronald; Cornish, Todd

2016-01-01

Chronic wasting disease (CWD) is an invariably fatal transmissible spongiform encephalopathy of white-tailed deer, mule deer, elk, and moose. Despite a 100% fatality rate, areas of high prevalence, and increasingly expanding geographic endemic areas, little is known about the population-level effects of CWD in deer. To investigate these effects, we tested the null hypothesis that high prevalence CWD did not negatively impact white-tailed deer population sustainability. The specific objectives of the study were to monitor CWD-positive and CWD-negative white-tailed deer in a high-prevalence CWD area longitudinally via radio-telemetry and global positioning system (GPS) collars. For the two populations, we determined the following: a) demographic and disease indices, b) annual survival, and c) finite rate of population growth (λ). The CWD prevalence was higher in females (42%) than males (28.8%) and hunter harvest and clinical CWD were the most frequent causes of mortality, with CWD-positive deer over-represented in harvest and total mortalities. Survival was significantly lower for CWD-positive deer and separately by sex; CWD-positive deer were 4.5 times more likely to die annually than CWD-negative deer while bucks were 1.7 times more likely to die than does. Population λ was 0.896 (0.859–0.980), which indicated a 10.4% annual decline. We show that a chronic disease that becomes endemic in wildlife populations has the potential to be population-limiting and the strong population-level effects of CWD suggest affected populations are not sustainable at high disease prevalence under current harvest levels.

Australian fitness professionals' level of interest in engaging with high health-risk population subgroups: findings from a national survey.

PubMed

Bennie, J A; Thomas, G; Wiesner, G H; van Uffelen, J G Z; Khan, A; Kolbe-Alexander, T; Vergeer, I; Biddle, S J H

2018-07-01

Fitness industry professionals (personal trainers, group instructors) may have a role in health promotion, particularly when working with subgroups with known health risks (e.g. older adults, obese). The aim of this study is to examine fitness professionals' level of interest in engaging with high-risk populations. Cross-sectional evaluation of a national survey. In 2014, 9100 Australian registered exercise professionals were invited to complete an online survey. Respondents reported their level of interest in engaging with nine health-risk population subgroups. A multivariable logistic regression analysis assessed the odds of being classified as having a 'low level' of interest in training high health-risk subgroups, adjusting for demographic and fitness industry-related factors. Of 1185 respondents (aged 17-72 years), 31.1% reported having a 'high level' of interest in training high health-risk subgroups. The highest level of interest was among 'obese clients' and 'adults (18-64 years) with chronic health conditions'. In the adjusted analysis, males (odds ratio [OR], 1.55, 95% confidence interval [CI]: 1.06-2.25) and those in urban settings (OR, 2.26, 95% CI: 1.54-3.37) were more likely to have a 'low level' of interest. Fitness professionals have a modest level of interest in training high health-risk subgroups. In addition to the development of strategies to increase interest, research should examine whether fitness professionals are able to safely prescribe exercise to high health-risk subgroups. Copyright © 2018. Published by Elsevier Ltd.

Temporal and spatial variation in alkaloid levels in Achnatherum robustum, a native grass infected with the endophyte Neotyphodium.

PubMed

Faeth, Stanley H; Gardner, Dale R; Hayes, Cinnamon J; Jani, Andrea; Wittlinger, Sally K; Jones, Thomas A

2006-02-01

The native North American perennial grass Achnatherum robustum (Vasey) Barkworth [= Stipa robusta (Vasey) Scribn.] or sleepygrass is toxic and narcotic to livestock. The causative agents are alkaloidal mycotoxins produced from infections by a systemic and asexual Neotyphodium endophyte. Recent studies suggest that toxicity is limited across the range of sleepygrass in the Southwest USA. We sampled 17 populations of sleepygrass with varying distance from one focal population known for its high toxicity levels near Cloudcroft, NM, USA. For some, we sampled individual plants twice within the same growing season and over successive years (2001-2004). We also determined infection levels in each population. In general, all populations were highly infected, but infection levels were more variable near the focal population. Only infected plants within populations near the Cloudcroft area produced alkaloids. The ergot alkaloid, ergonovine, comprised the bulk of the alkaloids, with lesser amounts of lysergic and isolysergic acid amides and ergonovinine alkaloids. Levels of all alkaloids were positively correlated among individual plants within and between growing seasons. Infected plants that produced no alkaloids in 1 yr did not produce any alkaloids within the same growing season or in other years. Levels of alkaloids in sleepygrass populations declined with distance from the Cloudcroft population, although infection levels increased. Infected plants in populations in northern New Mexico and southern Colorado produced no alkaloids at all despite 100% infectivity. Our results suggest that only specific Neotyphodium haplotypes or specific Neotyphodium-grass combinations produce ergot alkaloids in sleepygrass. The Neotyphodium haplotype or host-endophyte combination that produces toxic levels of alkaloids appears restricted to one locality across the range of sleepygrass. Because of the wide variation in alkaloid levels among populations, interactions between the endophyte and host, and consequences for herbivores, competitors, and pathogens and other components of the community, are likely to vary widely across the geographic range of this native grass.

Responses of chub (Leuciscus cephalus) populations to chemical stress, assessed by genetic markers, DNA damage and cytochrome P4501A induction.

PubMed

Larno, V; Laroche, J; Launey, S; Flammarion, P; Devaux, A

2001-06-01

Indicators of effects at the population level (genetic variation using allozymes) and early indicators of pollution (EROD activity and DNA strand break formation) were analysed in chub (Leuciscus cephalus) living in weakly and heavily contaminated stations of the Rhône River watershed. The genetic erosion was mainly detected in a fish population living in a contaminated small river system, through modifications in allelic and genotypic frequencies for PGM-2 locus and could be linked to a genetic bottleneck and to the reduced gene flow from upstream unable to maintain or restore the genetic diversity. In a contaminated large river system, the genetic diversity for PGM-2 and other loci was maintained and was probably the consequence of a high gene flow from upstream, linked to a sustained drift of larvae and juveniles in the system. A convergent increase of the frequency of the 90 allele at PGM-2 was observed in two contaminated stations compared with the reference station, this trend being confirmed on a more extensive geographic scale over the Rhône River basin. A high level of EROD activity was detected in both contaminated sites but only the fish in the large river system showed a significant DNA damage level compared to the reference population. The low DNA damage level and high hepato-somatic ratio characterized the impacted population of the small river system and could be associated to a chronic high-level exposure of fish to pollutants which selected individuals exhibiting a high level of DNA damage repair. In the two contaminated systems, some genotypes at the PGM-2 and EST-2 loci showed a low level of DNA damage and/or a high EROD activity and may be considered as being tolerant to pollutants. A higher tolerance of the most heterozygous fish was also detected in the contaminated large system and confirmed that a high level of heterozygosity may be necessary for survival in such a system.

Population movement can sustain STI prevalence in remote Australian indigenous communities.

PubMed

Hui, Ben B; Gray, Richard T; Wilson, David P; Ward, James S; Smith, Anthony M A; Philip, David J; Law, Matthew G; Hocking, Jane S; Regan, David G

2013-04-25

For almost two decades, chlamydia and gonorrhoea diagnosis rates in remote Indigenous communities have been up to 30 times higher than for non-Indigenous Australians. The high levels of population movement known to occur between remote communities may contribute to these high rates. We developed an individual-based computer simulation model to study the relationship between population movement and the persistence of gonorrhoea and chlamydia transmission within hypothetical remote communities. Results from our model suggest that short-term population movement can facilitate gonorrhoea and chlamydia persistence in small populations. By fixing the number of short-term travellers in accordance with census data, we found that these STIs can persist if at least 20% of individuals in the population seek additional partners while away from home and if the time away from home is less than 21 days. Periodic variations in travel patterns can contribute to increased sustainable levels of infection. Expanding existing STI testing and treatment programs to cater for short-term travellers is shown to be ineffective due to their short duration of stay. Testing and treatment strategies tailored to movement patterns, such as encouraging travellers to seek testing and treatment upon return from travel, will likely be more effective. High population mobility is likely to contribute to the high levels of STIs observed in remote Indigenous communities of Australia. More detailed data on mobility patterns and sexual behaviour of travellers will be invaluable for designing and assessing STI control programs in highly mobile communities.

Identification of a Major Locus Contributing to Erythrocyte 2,3-Diphosphoglycerate Variability in Hooded (Long-Evans) Rats

PubMed Central

Noble, N. A.; Brewer, G. J.

1977-01-01

The erythrocyte glycolytic intermediate 2,3-diphosphoglycerate (DPG) and adenosine triphosphate (ATP) play an important role in oxygen transport and delivery by binding to hemoglobin (Hb) and reducing its affinity for oxygen. Considerable quantitative variability in the levels of DPG and ATP exists in human populations and in a population of hooded (Long-Evans) rats we have studied. This paper presents the results of studies on the genetic component of DPG-level variation in an outbred population of hooded rats. Beginning with about 100 rats, a two-way selection experiment was initiated. Pairs of rats with the highest DPG levels were mated to produce a High-DPG rat strain and animals with the lowest DPG levels were mated to produce a Low-DPG strain. Mean DPG levels responded rapidly to selection and, from generation 3 on, the differences between strain means were highly significant. Ten High-DPG strain rats were intercrossed with 10 Low-DPG strain rats of generation 10 to produce an F1 generation in which the DPG levels were almost as high as those of High-DPG animals. This indicates partial dominance of High-DPG alleles. The F2 DPG-level distribution showed two distinct subpopulations. The high DPG subpopulation contained three times as many animals as the low DPG subpopulation. From these results and the statistical analyses performed, it was concluded that the DPG differences between strains were due to an allelic difference at one major locus, the allele carried by the High-DPG strain showing partial dominance over the allele carried by the Low-DPG strain. It appears that this locus may also effect ATP levels to a large extent and is polymorphic in hooded rat populations. Identification of this locus gives us a useful tool for studies of the physiological effects of DPG variability, as well as providing an example of a major gene effect in a quantitatively varying trait. PMID:863239

Research progress of plant population genomics based on high-throughput sequencing.

PubMed

Wang, Yun-sheng

2016-08-01

Population genomics, a new paradigm for population genetics, combine the concepts and techniques of genomics with the theoretical system of population genetics and improve our understanding of microevolution through identification of site-specific effect and genome-wide effects using genome-wide polymorphic sites genotypeing. With the appearance and improvement of the next generation high-throughput sequencing technology, the numbers of plant species with complete genome sequences increased rapidly and large scale resequencing has also been carried out in recent years. Parallel sequencing has also been done in some plant species without complete genome sequences. These studies have greatly promoted the development of population genomics and deepened our understanding of the genetic diversity, level of linking disequilibium, selection effect, demographical history and molecular mechanism of complex traits of relevant plant population at a genomic level. In this review, I briely introduced the concept and research methods of population genomics and summarized the research progress of plant population genomics based on high-throughput sequencing. I also discussed the prospect as well as existing problems of plant population genomics in order to provide references for related studies.

Urbanisation and incidence of psychosis and depression: follow-up study of 4.4 million women and men in Sweden.

PubMed

Sundquist, Kristina; Frank, Gölin; Sundquist, Jan

2004-04-01

Previous studies of differences in mental health between urban and rural populations are inconsistent. To examine whether a high level of urbanisation is associated with increased incidence rates of psychosis and depression, after adjustment for age, marital status, education and immigrant status. Follow-up study of the total Swedish population aged 25-64 years with respect to first hospital admission for psychosis or depression. Level of urbanisation was defined by population density and divided into quintiles. With increasing levels of urbanisation the incidence rates of psychosis and depression rose. In the full models, those living in the most densely populated areas (quintile 5) had 68-77% more risk of developing psychosis and 12-20% more risk of developing depression than the reference group (quintile 1). A high level of urbanisation is associated with increased risk of psychosis and depression for both women and men.

Beyond the Coral Triangle: high genetic diversity and near panmixia in Singapore's populations of the broadcast spawning sea star Protoreaster nodosus

PubMed Central

Tay, Y. C.; Chng, M. W. P.; Sew, W. W. G.; Rheindt, F. E.; Tun, K. P. P.

2016-01-01

The Coral Triangle is widely considered the most important centre of marine biodiversity in Asia while areas on its periphery such as the South China Sea, have received much less interest. Here, we demonstrate that a small population of the knobbly sea star Protoreaster nodosus in Singapore has similarly high levels of genetic diversity as comparable Indonesian populations from the Coral Triangle. The high genetic diversity of this population is remarkable because it is maintained despite decades of continued anthropogenic disturbance. We postulate that it is probably due to broadcast spawning which is likely to maintain high levels of population connectivity. To test this, we analysed 6140 genome-wide single nucleotide polymorphism (SNP) loci for Singapore's populations and demonstrate a pattern of near panmixia. We here document a second case of high genetic diversity and low genetic structure for a broadcast spawner in Singapore, which suggests that such species have high resilience against anthropogenic disturbances. The study demonstrates the feasibility and power of using genome-wide SNPs for connectivity studies of marine invertebrates without a sequenced genome. PMID:27853600

Intra-sexual competition alters the relationship between testosterone and ornament expression in a wild territorial bird.

PubMed

Martínez-Padilla, J; Pérez-Rodríguez, L; Mougeot, F; Ludwig, S; Redpath, S M

2014-05-01

In a reliable signalling system, individual quality is expected to mediate the costs associated with ornamental displays, with relatively lower costs being paid by individuals of higher quality. These relative costs should depend not only on individual quality, but also on levels of intra-sexual competition. We explored the current and delayed effects that testosterone implants have on bird ornamentation in populations with contrasted population densities, as a proxy for intra-sexual competition. In a replicated experiment, we manipulated testosterone in 196 yearling male red grouse Lagopus lagopus scoticus in autumn in populations of high and low levels of intra-sexual competition. Males were assigned to one of three exogenous testosterone (T) treatments: empty implants (T0), small T implants (T1) or larger T implants (T2). We monitored subsequent changes in testosterone levels, ornament size and carotenoid-based colouration, carotenoid levels and body condition from autumn to spring. Testosterone implants increased testosterone levels, comb redness and comb size, and decreased body condition but these effects depended on levels of intra-sexual competition. Specifically, T2-implanted birds increased testosterone levels and comb size more, and reduced body condition more, in populations where intra-sexual competition was low. In the following spring, testosterone levels of T2-treated birds kept increasing in populations where intra-sexual competition was high but not in populations where intra-sexual competition was low. Our results highlight that levels of intra-sexual competition alter the relationship between testosterone levels and ornament expression, influencing their condition-dependence; they also indicate that the outcome of standard hormone manipulation conducted in free-living animals vary depending on the population context. Copyright © 2014 Elsevier Inc. All rights reserved.

Potential for the evolution of heavy metal tolerance in Bryum argenteum, a moss. I. Variation within and among populations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shaw, J.; Beer, S.C.; Lutz, J.

Bryum argenteum frequently occurs in urban environments and therefore appears to have the ability to tolerate high levels of such atmospheric pollutants as lead. The presence of genetic variation for tolerance to lead was assessed within and among three populations of this species from Ithaca, New York state. Plants from these populations contained extremely different concentrations of lead and other metals, but there was little or no variation in metal tolerance among the populations. There were, however, significant differences in general vigor (growth rates across all experimental treatments) among populations. Moreover, the rural and suburban populations contained high levels ofmore » variation in vigor among haploid-sib families (families of gametophytes derived from different sporophytes). The urban population, in contrast, contained conspicuously less variation than the other two.« less

Microsatellite data suggest significant population structure and differentiation within the malaria vector Anopheles darlingi in Central and South America.

PubMed

Mirabello, Lisa; Vineis, Joseph H; Yanoviak, Stephen P; Scarpassa, Vera M; Póvoa, Marinete M; Padilla, Norma; Achee, Nicole L; Conn, Jan E

2008-03-26

Anopheles darlingi is the most important malaria vector in the Neotropics. An understanding of A. darlingi's population structure and contemporary gene flow patterns is necessary if vector populations are to be successfully controlled. We assessed population genetic structure and levels of differentiation based on 1,376 samples from 31 localities throughout the Peruvian and Brazilian Amazon and Central America using 5-8 microsatellite loci. We found high levels of polymorphism for all of the Amazonian populations (mean RS = 7.62, mean HO = 0.742), and low levels for the Belize and Guatemalan populations (mean RS = 4.3, mean HO = 0.457). The Bayesian clustering analysis revealed five population clusters: northeastern Amazonian Brazil, southeastern and central Amazonian Brazil, western and central Amazonian Brazil, Peruvian Amazon, and the Central American populations. Within Central America there was low non-significant differentiation, except for between the populations separated by the Maya Mountains. Within Amazonia there was a moderate level of significant differentiation attributed to isolation by distance. Within Peru there was no significant population structure and low differentiation, and some evidence of a population expansion. The pairwise estimates of genetic differentiation between Central America and Amazonian populations were all very high and highly significant (FST = 0.1859 - 0.3901, P < 0.05). Both the DA and FST distance-based trees illustrated the main division to be between Central America and Amazonia. We detected a large amount of population structure in Amazonia, with three population clusters within Brazil and one including the Peru populations. The considerable differences in Ne among the populations may have contributed to the observed genetic differentiation. All of the data suggest that the primary division within A. darlingi corresponds to two white gene genotypes between Amazonia (genotype 1) and Central America, parts of Colombia and Venezuela (genotype 2), and are in agreement with previously published mitochondrial COI gene sequences interpreted as incipient species. Overall, it appears that two main factors have contributed to the genetic differentiation between the population clusters: physical distance between the populations and the differences in effective population sizes among the subpopulations.

High Levels of Resistance in the Common Bed Bug, Cimex lectularius (Hemiptera: Cimicidae), to Neonicotinoid Insecticides.

PubMed

Romero, Alvaro; Anderson, Troy D

2016-05-01

The rapid increase of bed bug populations resistant to pyrethroids demands the development of novel control tactics. Products combining pyrethroids and neonicotinoids have become very popular for bed bug control in the United States, but there are concerns about evolution of resistance to these compounds. Laboratory assays were used to measure the toxicity of topical applications of four neonicotinoids to a susceptible population and three pyrethroid-resistant populations. Activity of esterases, glutathione S-transferases, and cytochrome P450s of all strains was also evaluated. High levels of resistance to four neonicotinoids, acetamiprid, imidacloprid, dinotefuran, and thiamethoxam, relative to the susceptible Fort Dix population, were detected in populations collected from human dwellings in Cincinnati and Michigan. Because activity of detoxifying enzymes was increased in these two populations, our results suggest that these enzymes have some involvement in neonicotinoid resistance, but other resistance mechanisms might be involved as well. Detection of high levels of resistance to neonicotinoids further limits the options for chemical control of bed bugs. Published by Oxford University Press on behalf of Entomological Society of America 2016. This work is written by US Government employees and is in the public domain in the US.

Population genetics of the westernmost distribution of the glaciations-surviving black truffle Tuber melanosporum.

PubMed

García-Cunchillos, Iván; Sánchez, Sergio; Barriuso, Juan José; Pérez-Collazos, Ernesto

2014-04-01

The black truffle (Tuber melanosporum Vittad.) is an important natural resource due to its relevance as a delicacy in gastronomy. Different aspects of this hypogeous fungus species have been studied, including population genetics of French and Italian distribution ranges. Although those studies include some Spanish populations, this is the first time that the genetic diversity and genetic structure of the wide geographical range of the natural Spanish populations have been analysed. To achieve this goal, 23 natural populations were sampled across the Spanish geographical distribution. ISSR technique demonstrated its reliability and capability to detect high levels of polymorphism in the species. Studied populations showed high levels of genetic diversity (h N  = 0.393, h S  = 0.678, Hs = 0.418), indicating a non threatened genetic conservation status. These high levels may be a consequence of the wide distribution range of the species, of its spore dispersion by animals, and by its evolutionary history. AMOVA analysis showed a high degree of genetic structure among populations (47.89%) and other partitions as geographical ranges. Bayesian genetic structure analyses differentiated two main Spanish groups separated by the Iberian Mountain System, and showed the genetic uniqueness of some populations. Our results suggest the survival of some of these populations during the last glaciation, the Spanish southern distribution range perhaps surviving as had occurred in France and Italy, but it is also likely that specific northern areas may have acted as a refugia for the later dispersion to other calcareous areas in the Iberian Peninsula and probably France.

An Evaluation of Population Density Mapping and Built up Area Estimates in Sri Lanka Using Multiple Methodologies

NASA Astrophysics Data System (ADS)

Engstrom, R.; Soundararajan, V.; Newhouse, D.

2017-12-01

In this study we examine how well multiple population density and built up estimates that utilize satellite data compare in Sri Lanka. The population relationship is examined at the Gram Niladhari (GN) level, the lowest administrative unit in Sri Lanka from the 2011 census. For this study we have two spatial domains, the whole country and a 3,500km2 sub-sample, for which we have complete high spatial resolution imagery coverage. For both the entire country and the sub-sample we examine how consistent are the existing publicly available measures of population constructed from satellite imagery at predicting population density? For just the sub-sample we examine how well do a suite of values derived from high spatial resolution satellite imagery predict population density and how does our built up area estimate compare to other publicly available estimates. Population measures were obtained from the Sri Lankan census, and were downloaded from Facebook, WorldPoP, GPW, and Landscan. Percentage built-up area at the GN level was calculated from three sources: Facebook, Global Urban Footprint (GUF), and the Global Human Settlement Layer (GHSL). For the sub-sample we have derived a variety of indicators from the high spatial resolution imagery. Using deep learning convolutional neural networks, an object oriented, and a non-overlapping block, spatial feature approach. Variables calculated include: cars, shadows (a proxy for building height), built up area, and buildings, roof types, roads, type of agriculture, NDVI, Pantex, and Histogram of Oriented Gradients (HOG) and others. Results indicate that population estimates are accurate at the higher, DS Division level but not necessarily at the GN level. Estimates from Facebook correlated well with census population (GN correlation of 0.91) but measures from GPW and WorldPop are more weakly correlated (0.64 and 0.34). Estimates of built-up area appear to be reliable. In the 32 DSD-subsample, Facebook's built- up area measure is highly correlated with our built-up measure (correlation of 0.9). Preliminary regression results based on variables selected from Lasso-regressions indicate that satellite indicators have exceptionally strong predictive power in predicting GN level population level and density with an out of sample r-squared of 0.75 and 0.72 respectively.

Genetic Diversity of Ascaris in China Assessed Using Simple Sequence Repeat Markers.

PubMed

Zhou, Chunhua; Jian, Shaoqing; Peng, Weidong; Li, Min

2018-04-01

The giant roundworm Ascaris infects pigs and people worldwide and causes serious diseases. The taxonomic relationship between Ascaris suum and Ascaris lumbricoides is still unclear. The purpose of the present study was to investigate the genetic diversity and population genetic structure of 258 Ascaris specimens from humans and pigs from 6 sympatric regions in Ascaris -endemic regions of China using existing simple sequence repeat data. The microsatellite markers showed a high level of allelic richness and genetic diversity in the samples. Each of the populations demonstrated excess homozygosity (Ho0). According to a genetic differentiation index (Fst=0.0593), there was a high-level of gene flow in the Ascaris populations. A hierarchical analysis on molecular variance revealed remarkably high levels of variation within the populations. Moreover, a population structure analysis indicated that Ascaris populations fell into 3 main genetic clusters, interpreted as A. suum , A. lumbricoides , and a hybrid of the species. We speculated that humans can be infected with A. lumbricoides , A. suum , and the hybrid, but pigs were mainly infected with A. suum . This study provided new information on the genetic diversity and population structure of Ascaris from human and pigs in China, which can be used for designing Ascaris control strategies. It can also be beneficial to understand the introgression of host affiliation.

A geographic analysis of population density thresholds in the influenza pandemic of 1918-19.

PubMed

Chandra, Siddharth; Kassens-Noor, Eva; Kuljanin, Goran; Vertalka, Joshua

2013-02-20

Geographic variables play an important role in the study of epidemics. The role of one such variable, population density, in the spread of influenza is controversial. Prior studies have tested for such a role using arbitrary thresholds for population density above or below which places are hypothesized to have higher or lower mortality. The results of such studies are mixed. The objective of this study is to estimate, rather than assume, a threshold level of population density that separates low-density regions from high-density regions on the basis of population loss during an influenza pandemic. We study the case of the influenza pandemic of 1918-19 in India, where over 15 million people died in the short span of less than one year. Using data from six censuses for 199 districts of India (n=1194), the country with the largest number of deaths from the influenza of 1918-19, we use a sample-splitting method embedded within a population growth model that explicitly quantifies population loss from the pandemic to estimate a threshold level of population density that separates low-density districts from high-density districts. The results demonstrate a threshold level of population density of 175 people per square mile. A concurrent finding is that districts on the low side of the threshold experienced rates of population loss (3.72%) that were lower than districts on the high side of the threshold (4.69%). This paper introduces a useful analytic tool to the health geographic literature. It illustrates an application of the tool to demonstrate that it can be useful for pandemic awareness and preparedness efforts. Specifically, it estimates a level of population density above which policies to socially distance, redistribute or quarantine populations are likely to be more effective than they are for areas with population densities that lie below the threshold.

A geographic analysis of population density thresholds in the influenza pandemic of 1918–19

PubMed Central

2013-01-01

Background Geographic variables play an important role in the study of epidemics. The role of one such variable, population density, in the spread of influenza is controversial. Prior studies have tested for such a role using arbitrary thresholds for population density above or below which places are hypothesized to have higher or lower mortality. The results of such studies are mixed. The objective of this study is to estimate, rather than assume, a threshold level of population density that separates low-density regions from high-density regions on the basis of population loss during an influenza pandemic. We study the case of the influenza pandemic of 1918–19 in India, where over 15 million people died in the short span of less than one year. Methods Using data from six censuses for 199 districts of India (n=1194), the country with the largest number of deaths from the influenza of 1918–19, we use a sample-splitting method embedded within a population growth model that explicitly quantifies population loss from the pandemic to estimate a threshold level of population density that separates low-density districts from high-density districts. Results The results demonstrate a threshold level of population density of 175 people per square mile. A concurrent finding is that districts on the low side of the threshold experienced rates of population loss (3.72%) that were lower than districts on the high side of the threshold (4.69%). Conclusions This paper introduces a useful analytic tool to the health geographic literature. It illustrates an application of the tool to demonstrate that it can be useful for pandemic awareness and preparedness efforts. Specifically, it estimates a level of population density above which policies to socially distance, redistribute or quarantine populations are likely to be more effective than they are for areas with population densities that lie below the threshold. PMID:23425498

A case history of a dynamic resource--the red fox

USGS Publications Warehouse

Sargeant, A.B.; Sanderson, G.C.

1982-01-01

Red fox (Vulpes vulpes) population trends in midwestern North America since 1800 were examined. During 1801-1900, the red fox expanded its range south to include most of the region, but populations remained low in most areas. During 1901-30, it became scarce or absent in many northern areas but was common in southern areas. During 1931-45, populations in most of the region increased to high levels. From 1946 to 1980 populations remained high and westward range expansions occurred on the northern plains. Three factors appear primarily responsible for major population changes. Habitat conditions improved after settlement, but in many areas population buildup was delayed. Interspecific canid competition, especially from expanding coyote (Canis latrans) populations, held red fox populations at low levels, especially in the west. Excessive harvest for fur contributed to holding populations down in many areas, especially during the early 1900's when pelt values were exceptionally high. Major population increases during the 1930's and early 1940's coincided with declining pelt prices and resulted in widespread implementation of fox bounties. In the 1960's, bounties were gradually discontinued, pelt prices increased, and restrictions on season length and harvest methods were implemented in most states.

The Relationship between General Population Suicide Rates and Educational Attainment: A Cross-National Study

ERIC Educational Resources Information Center

Shah, Ajit; Bhandarkar, Ritesh

2009-01-01

Suicides are associated with both high and low levels of intelligence and educational attainment in both individual-level and aggregate-level studies. A cross-national study examining the relationship between general population suicide rates ("y") and educational attainment ("x") was undertaken with the "a priori" hypothesis that the relationship…

Heterozygosity-fitness correlations among wild populations of European tree frog (Hyla arborea) detect fixation load.

PubMed

Luquet, E; David, P; Lena, J-P; Joly, P; Konecny, L; Dufresnes, C; Perrin, N; Plenet, S

2011-05-01

Quantifying the impacts of inbreeding and genetic drift on fitness traits in fragmented populations is becoming a major goal in conservation biology. Such impacts occur at different levels and involve different sets of loci. Genetic drift randomly fixes slightly deleterious alleles leading to different fixation load among populations. By contrast, inbreeding depression arises from highly deleterious alleles in segregation within a population and creates variation among individuals. A popular approach is to measure correlations between molecular variation and phenotypic performances. This approach has been mainly used at the individual level to detect inbreeding depression within populations and sometimes at the population level but without consideration about the genetic processes measured. For the first time, we used in this study a molecular approach considering both the interpopulation and intrapopulation level to discriminate the relative importance of inbreeding depression vs. fixation load in isolated and non-fragmented populations of European tree frog (Hyla arborea), complemented with interpopulational crosses. We demonstrated that the positive correlations observed between genetic heterozygosity and larval performances on merged data were mainly caused by co-variations in genetic diversity and fixation load among populations rather than by inbreeding depression and segregating deleterious alleles within populations. Such a method is highly relevant in a conservation perspective because, depending on how populations lose fitness (inbreeding vs. fixation load), specific management actions may be designed to improve the persistence of populations. © 2011 Blackwell Publishing Ltd.

High-resolution tide projections reveal extinction threshold in response to sea-level rise.

PubMed

Field, Christopher R; Bayard, Trina S; Gjerdrum, Carina; Hill, Jason M; Meiman, Susan; Elphick, Chris S

2017-05-01

Sea-level rise will affect coastal species worldwide, but models that aim to predict these effects are typically based on simple measures of sea level that do not capture its inherent complexity, especially variation over timescales shorter than 1 year. Coastal species might be most affected, however, by floods that exceed a critical threshold. The frequency and duration of such floods may be more important to population dynamics than mean measures of sea level. In particular, the potential for changes in the frequency and duration of flooding events to result in nonlinear population responses or biological thresholds merits further research, but may require that models incorporate greater resolution in sea level than is typically used. We created population simulations for a threatened songbird, the saltmarsh sparrow (Ammodramus caudacutus), in a region where sea level is predictable with high accuracy and precision. We show that incorporating the timing of semidiurnal high tide events throughout the breeding season, including how this timing is affected by mean sea-level rise, predicts a reproductive threshold that is likely to cause a rapid demographic shift. This shift is likely to threaten the persistence of saltmarsh sparrows beyond 2060 and could cause extinction as soon as 2035. Neither extinction date nor the population trajectory was sensitive to the emissions scenarios underlying sea-level projections, as most of the population decline occurred before scenarios diverge. Our results suggest that the variation and complexity of climate-driven variables could be important for understanding the potential responses of coastal species to sea-level rise, especially for species that rely on coastal areas for reproduction. © 2016 John Wiley & Sons Ltd.

Confirmation of putative stormwater impact on water quality at a Florida beach by microbial source tracking methods and structure of indicator organism populations.

PubMed

Brownell, M J; Harwood, V J; Kurz, R C; McQuaig, S M; Lukasik, J; Scott, T M

2007-08-01

The effect of a stormwater conveyance system on indicator bacteria levels at a Florida beach was assessed using microbial source tracking methods, and by investigating indicator bacteria population structure in water and sediments. During a rain event, regulatory standards for both fecal coliforms and Enterococcus spp. were exceeded, contrasting with significantly lower levels under dry conditions. Indicator bacteria levels were high in sediments under all conditions. The involvement of human sewage in the contamination was investigated using polymerase chain reaction (PCR) assays for the esp gene of Enterococcus faecium and for the conserved T antigen of human polyomaviruses, all of which were negative. BOX-PCR subtyping of Escherichia coli and Enterococcus showed higher population diversity during the rain event; and higher population similarity during dry conditions, suggesting that without fresh inputs, only a subset of the population survives the selective pressure of the secondary habitat. These data indicate that high indicator bacteria levels were attributable to a stormwater system that acted as a reservoir and conduit, flushing high levels of indicator bacteria to the beach during a rain event. Such environmental reservoirs of indicator bacteria further complicate the already questionable relationship between indicator organisms and human pathogens, and call for a better understanding of the ecology, fate and persistence of indicator bacteria.

Individual and population-level responses to ocean acidification.

PubMed

Harvey, Ben P; McKeown, Niall J; Rastrick, Samuel P S; Bertolini, Camilla; Foggo, Andy; Graham, Helen; Hall-Spencer, Jason M; Milazzo, Marco; Shaw, Paul W; Small, Daniel P; Moore, Pippa J

2016-01-29

Ocean acidification is predicted to have detrimental effects on many marine organisms and ecological processes. Despite growing evidence for direct impacts on specific species, few studies have simultaneously considered the effects of ocean acidification on individuals (e.g. consequences for energy budgets and resource partitioning) and population level demographic processes. Here we show that ocean acidification increases energetic demands on gastropods resulting in altered energy allocation, i.e. reduced shell size but increased body mass. When scaled up to the population level, long-term exposure to ocean acidification altered population demography, with evidence of a reduction in the proportion of females in the population and genetic signatures of increased variance in reproductive success among individuals. Such increased variance enhances levels of short-term genetic drift which is predicted to inhibit adaptation. Our study indicates that even against a background of high gene flow, ocean acidification is driving individual- and population-level changes that will impact eco-evolutionary trajectories.

Conservation implications of the genetic diversity of Gymnospermium microrrhynchum in Korea.

PubMed

Lee, S H; Yeon, M H; Shim, J K

2016-10-24

Gymnospermium microrrhynchum (Berberidaceae) is an ephemeral perennial herb with a limited distributional range in the Baekdudaegan mountain areas of the Korean Peninsula, and is designated a rare plant by the Korean Forest Service. Information about its genetic variation and structure is important for developing successful conservation strategies. To investigate the genetic variation within and among seven G. microrrhynchum populations, random amplified polymorphic DNA data were obtained for 207 individuals. The populations exhibited relatively low genetic diversity: the percentage of polymorphic bands (PPB) ranged from 32.1 to 66.7% (mean = 51.4%) and Nei's gene diversity (H E ) ranged from 0.116 to 0.248 (mean = 0.188). However, genetic diversity at the species level was relatively high (PPB = 98.7%, H E = 0.349). An analysis of molecular variance revealed high differentiation among populations (Φ ST = 0.6818), but the low gene flow value (N m = 0.117) suggests a low level of gene exchange occurs among populations. Principal coordinates analysis revealed that individuals were separated according to population. The high level of genetic differentiation and restricted gene flow among G. microrrhynchum populations, which resulted from their isolation in alpine areas after the Ice Age, indicates that it is essential to protect and manage all populations, rather than focus on specific populations, in order to maintain the genetic diversity of this species.

Effect of APOE ε4 allele on survival and fertility in an adverse environment.

PubMed

van Exel, Eric; Koopman, Jacob J E; Bodegom, David van; Meij, Johannes J; Knijff, Peter de; Ziem, Juventus B; Finch, Caleb E; Westendorp, Rudi G J

2017-01-01

The apolipoprotein-ε4 allele (APOE-ε4) is strongly associated with detrimental outcomes in affluent populations including atherosclerotic disease, Alzheimer's disease, and reduced lifespan. Despite these detrimental outcomes, population frequencies of APOE-ε4 are high. We hypothesize that the high frequency of APOE-ε4 was maintained because of beneficial effects during evolution when infectious pathogens were more prevalent and a major cause of mortality. We examined a rural Ghanaian population with a high pathogen exposure for selective advantages of APOE-ε4, to survival and or fertility. This rural Ghanaian population (n = 4311) has high levels of mortality from widespread infectious diseases which are the main cause of death. We examined whether APOE-ε4 was associated with survival (total follow-up time was 30,262 years) and fertility after stratifying by exposure to high or low pathogen levels. Households drawing water from open wells and rivers were classified as exposed to high pathogen levels while low pathogen exposure was classified as those drawing water from borehole wells. We found a non-significant, but positive survival benefit, i.e. the hazard ratio per APOE-ε4 allele was 0.80 (95% confidence interval: 0.69 to 1.05), adjusted for sex, tribe, and socioeconomic status. Among women aged 40 years and older (n = 842), APOE-ε4 was not associated with the lifetime number of children. However, APOE-ε4 was associated with higher fertility in women exposed to high pathogen levels. Compared with women not carrying an APOE-ε4 allele, those carrying one APOE-ε4 allele had on average one more child and those carrying two APOE-ε4 alleles had 3.5 more children (p = 0.018). Contrary to affluent modern-day populations, APOE-ε4 did not carry a survival disadvantage in this rural Ghanaian population. Moreover, APOE-ε4 promotes fertility in highly infectious environments. Our findings suggest that APOE-ε4 may be considered as evolutionarily adaptive. Its adverse associations in affluent modern populations with later onset diseases of aging further characterize APOE-ε4 as an example of antagonistic pleiotropy.

Molecular diversity and population structure of the forage grass Hemarthria compressa (Poaceae) in south China based on SRAP markers.

PubMed

Huang, L-K; Zhang, X-Q; Xie, W-G; Zhang, J; Cheng, L; Yan, H D

2012-08-16

Hemarthria compressa is one of the most important and widely utilized forage crops in south China, owing to its high forage yield and capability of adaptation to hot and humid conditions. We examined the population structure and genetic variation within and among 12 populations of H. compressa in south China using sequence-related amplified polymorphism (SRAP) markers. High genetic diversity was found in these samples [percentage polymorphic bands (PPB) = 82.21%, Shannon's diversity index (I) = 0.352]. However, there was relatively low level of genetic diversity at the population level (PPB = 29.17%, I = 0.155). A high degree of genetic differentiation among populations was detected based on other measures and molecular markers (Nei's genetic diversity analysis: G(ST) = 54.19%; AMOVA analysis: F(ST) = 53.35%). The SRAP markers were found to be more efficient than ISSR markers for evaluating population diversity. Based on these findings, we propose changes in sampling strategies for appraising and utilizing the genetic resources of this species.

Comparative Population Genomics Analysis of the Mammalian Fungal Pathogen Pneumocystis.

PubMed

Cissé, Ousmane H; Ma, Liang; Wei Huang, Da; Khil, Pavel P; Dekker, John P; Kutty, Geetha; Bishop, Lisa; Liu, Yueqin; Deng, Xilong; Hauser, Philippe M; Pagni, Marco; Hirsch, Vanessa; Lempicki, Richard A; Stajich, Jason E; Cuomo, Christina A; Kovacs, Joseph A

2018-05-08

Pneumocystis species are opportunistic mammalian pathogens that cause severe pneumonia in immunocompromised individuals. These fungi are highly host specific and uncultivable in vitro Human Pneumocystis infections present major challenges because of a limited therapeutic arsenal and the rise of drug resistance. To investigate the diversity and demographic history of natural populations of Pneumocystis infecting humans, rats, and mice, we performed whole-genome and large-scale multilocus sequencing of infected tissues collected in various geographic locations. Here, we detected reduced levels of recombination and variations in historical demography, which shape the global population structures. We report estimates of evolutionary rates, levels of genetic diversity, and population sizes. Molecular clock estimates indicate that Pneumocystis species diverged before their hosts, while the asynchronous timing of population declines suggests host shifts. Our results have uncovered complex patterns of genetic variation influenced by multiple factors that shaped the adaptation of Pneumocystis populations during their spread across mammals. IMPORTANCE Understanding how natural pathogen populations evolve and identifying the determinants of genetic variation are central issues in evolutionary biology. Pneumocystis , a fungal pathogen which infects mammals exclusively, provides opportunities to explore these issues. In humans, Pneumocystis can cause a life-threatening pneumonia in immunosuppressed individuals. In analysis of different Pneumocystis species infecting humans, rats, and mice, we found that there are high infection rates and that natural populations maintain a high level of genetic variation despite low levels of recombination. We found no evidence of population structuring by geography. Our comparisons of the times of divergence of these species to their respective hosts suggest that Pneumocystis may have undergone recent host shifts. The results demonstrate that Pneumocystis strains are widely disseminated geographically and provide a new understanding of the evolution of these pathogens.

Economic level and human longevity: Spatial and temporal variations and correlation analysis of per capita GDP and longevity indicators in China.

PubMed

Wang, Shaobin; Luo, Kunli; Liu, Yonglin; Zhang, Shixi; Lin, Xiaoxu; Ni, Runxiang; Tian, Xinglei; Gao, Xing

2015-01-01

We show the variation of longevity indicators in China during the past 60 years and its correlation patterns with per capita GDP (GDPpc) both at provincial and inner-provincial level. Population data from six national population censuses in China (1953-2010) at provincial level and in several typical provinces in 2010 at county-level were selected. Four main longevity indicators were calculated. Pearson's r and distributed lags time series analysis between longevity indicators and GDPpc were conducted. The results show that Guangxi and Hainan Provinces maintain relatively high long-lived population (population over the age of 90) across various population censuses. The distributions of the population over the age of 80 and life expectancy are significantly affected by both contemporaneous and historical GDPpc at provincial level. However, areas of high long-lived population (over the age of 90) exhibit continuously stable features that lack any significant correlation with GDPpc both at provincial and inner-provincial level. Our results indicate a mixed distribution pattern of several longevity indexes and different relation to GDPpc. It shows consistent trend with Preston curve, that is, economic conditions may have limited influence on human longevity, especially for those who live longer than 90 years old. This study suggests that the economic development may favor the local residents to have access to live as old as 80 years old, but it is still difficult for most residents to reach the level of centenarians. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

[Workplace stress and its impact on the 16-year risk of myocardial infarction and stroke in an open female population aged 25-64 years in Russia/Siberia (WHO MONICA-psychosocial program)].

PubMed

Gafarov, V V; Panov, D O; Gromova, E A; Gagulin, I V; Gafarova, A V

2015-01-01

To determine the impact of workplace stress on the hazard ratio (HR) of myocardial infarction (M) and stroke in an open female population aged 25-64 years in Russia/Siberia (Novosibirsk) for 16 years. A random representative sample of 25-64-year-old women (n=870) residing in a Novosibirsk district was surveyed within the framework of the WHO program. Workplace stress was investigated using the Karasek scale; an attitude towards work and health prophylactic examinations was studied applying the Health Awareness and Attitude questionnaire of the WHO program. For 16 years (1994 to 2010), a cohort of all new cases of MI and stroke was examined employing the WHO program and all possible medical records. The Cox regression model was used to determine HR for MI and stroke in the open female population aged 25-64 years for 16 years. The prevalence of high-level stress in the open female population aged 25-64 years was 31.6%. The high level of job stress was associated with a high responsibility, impossibility to have a rest at the end of a working day, frequent professional dissatisfaction, and a reduced work capacity. During 16 years, the women having high-level job stress showed a 3.22- and 1.96-fold increases in the HR of MI (p<0.05) and stroke (p<0.05), respectively. The incidence of MI and stroke was higher in married women expressing job stress as managers or manual laborers and having high and low educational attainment. The prevalence of high-level workplace stress was substantial in the open population of 25-64-year-old women in Russia/Siberia (Novosibirsk). The stress-related HR of Ml and stroke was 3-2 times higher than in those without high-level stress. The HR of MI and stroke is affected by a social gradient.

Low reproductive isolation and highly variable levels of gene flow reveal limited progress towards speciation between European river and brook lampreys.

PubMed

Rougemont, Q; Gaigher, A; Lasne, E; Côte, J; Coke, M; Besnard, A-L; Launey, S; Evanno, G

2015-12-01

Ecologically based divergent selection is a factor that could drive reproductive isolation even in the presence of gene flow. Population pairs arrayed along a continuum of divergence provide a good opportunity to address this issue. Here, we used a combination of mating trials, experimental crosses and population genetic analyses to investigate the evolution of reproductive isolation between two closely related species of lampreys with distinct life histories. We used microsatellite markers to genotype over 1000 individuals of the migratory parasitic river lamprey (Lampetra fluviatilis) and freshwater-resident nonparasitic brook lamprey (Lampetra planeri) distributed in 10 sympatric and parapatric population pairs in France. Mating trials, parentage analyses and artificial fertilizations demonstrated a low level of reproductive isolation between species even though size-assortative mating may contribute to isolation. Most parapatric population pairs were strongly differentiated due to the joint effects of geographic distance and barriers to migration. In contrast, we found variable levels of gene flow between sympatric populations ranging from panmixia to moderate differentiation, which indicates a gradient of divergence with some population pairs that may correspond to alternative morphs or ecotypes of a single species and others that remain partially isolated. Ecologically based divergent selection may explain these variable levels of divergence among sympatric population pairs, but incomplete genome swamping following secondary contact could have also played a role. Overall, this study illustrates how highly differentiated phenotypes can be maintained despite high levels of gene flow that limit the progress towards speciation. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

Dybowski's sika deer (Cervus nippon hortulorum): genetic divergence between natural primorian and introduced Czech populations.

PubMed

Krojerová-Prokesová, Jarmila; Baranceková, Miroslava; Voloshina, Inna; Myslenkov, Alexander; Lamka, Jirí; Koubek, Petr

2013-01-01

Dybowski's sika deer (Cervus nippon hortulorum) originally inhabited the majority of the Primorsky Krai in Far Eastern Russia, north-eastern China, and Korean Peninsula. At present, only the Russian population seems to be stable, even though this taxon is still classified as endangered by the Russian Federation. Almost 100 years ago, this subspecies, among others, was imported to several European countries including the Czech Republic. We used both mitochondrial (mtDNA; the cytochrome b gene and the control region) and nuclear DNA markers to examine the actual taxonomic status of modern Czech Dybowski's sika population and to compare the genetic diversity between the introduced and the native populations. Altogether, 124 Czech samples and 109 Primorian samples were used in the analyses. Within the samples obtained from individuals that were all morphologically classified as Dybowski's sika, we detected mtDNA haplotypes of Dybowski's sika (84 samples), as well as those belonging to other sika subspecies: northern Japanese sika (25 samples), southern Japanese sika (6 samples), and south-eastern Chinese sika (8 samples). Microsatellite analysis revealed a certain level of heterozygote deficiency and a high level of inbreeding in both populations. The high number of private alleles, factorial correspondence analysis, and Bayesian clustering analysis indicate a high level of divergence between both populations. The large degree of differentiation and the high number of population-specific alleles could be a result of a founder effect, could be a result of a previously suggested bottleneck within the Primorian population, and could also be affected by the crossbreeding of captive individuals with other sika subspecies.

Terrorism-related fear and avoidance behavior in a multiethnic urban population.

PubMed

Eisenman, David P; Glik, Deborah; Ong, Michael; Zhou, Qiong; Tseng, Chi-Hong; Long, Anna; Fielding, Jonathan; Asch, Steven

2009-01-01

We sought to determine whether groups traditionally most vulnerable to disasters would be more likely than would be others to perceive population-level risk as high (as measured by the estimated color-coded alert level) would worry more about terrorism, and would avoid activities because of terrorism concerns. We conducted a random digit dial survey of the Los Angeles County population October 2004 through January 2005 in 6 languages. We asked respondents what color alert level the country was under, how often they worry about terrorist attacks, and how often they avoid activities because of terrorism. Multivariate regression modeled correlates of worry and avoidance, including mental illness, disability, demographic factors, and estimated color-coded alert level. Persons who are mentally ill, those who are disabled, African Americans, Latinos, Chinese Americans, Korean Americans, and non-US citizens were more likely to perceive population-level risk as high, as measured by the estimated color-coded alert level. These groups also reported more worry and avoidance behaviors because of concerns about terrorism. Vulnerable populations experience a disproportionate burden of the psychosocial impact of terrorism threats and our national response. Further studies should investigate the specific behaviors affected and further elucidate disparities in the disaster burden associated with terrorism and terrorism policies.

Terrorism-Related Fear and Avoidance Behavior in a Multiethnic Urban Population

PubMed Central

Glik, Deborah; Ong, Michael; Zhou, Qiong; Tseng, Chi-Hong; Long, Anna; Fielding, Jonathan; Asch, Steven

2009-01-01

Objectives. We sought to determine whether groups traditionally most vulnerable to disasters would be more likely than would be others to perceive population-level risk as high (as measured by the estimated color-coded alert level) would worry more about terrorism, and would avoid activities because of terrorism concerns. Methods. We conducted a random digit dial survey of the Los Angeles County population October 2004 through January 2005 in 6 languages. We asked respondents what color alert level the country was under, how often they worry about terrorist attacks, and how often they avoid activities because of terrorism. Multivariate regression modeled correlates of worry and avoidance, including mental illness, disability, demographic factors, and estimated color-coded alert level. Results. Persons who are mentally ill, those who are disabled, African Americans, Latinos, Chinese Americans, Korean Americans, and non-US citizens were more likely to perceive population-level risk as high, as measured by the estimated color-coded alert level. These groups also reported more worry and avoidance behaviors because of concerns about terrorism. Conclusions. Vulnerable populations experience a disproportionate burden of the psychosocial impact of terrorism threats and our national response. Further studies should investigate the specific behaviors affected and further elucidate disparities in the disaster burden associated with terrorism and terrorism policies. PMID:19008521

Genetic population structure of the recently introduced Asian clam, Potamocorbula amurensis, in San Francisco Bay

USGS Publications Warehouse

Duda, T. F.

1994-01-01

The genetic population structure of the recently introduced Asian clam, Potamocorbula amurensis, in San Francisco Bay was described using starch gel electrophoresis at eight presumptive loci. Specimens were taken from five environmentally distinct sites located throughout the bay. The population maintains a high degree of genetic variation, with a mean heterozygosity of 0.295, a mean polymorphism of 0.75, and an average of 3.70 alleles per locus. The population is genetically homogeneous, as evidenced from genetic distance values and F-statistics. However, heterogeneity of populations was indicated from a contingency chi-square test. Significant deviations from Hardy-Weinberg equilibrium and heterozygote deficiencies were found at the Lap-1 locus for all populations and at the Lap-2 locus for a single population. High levels of variability could represent a universal characteristic of invading species, the levels of variability in the source population(s), and/or the dynamics of the introduction. Lack of differentiation between subpopulations may be due to the immaturity of the San Francisco Bay population, the “general purpose” phenotype genetic strategy of the species, high rates of gene flow in the population, and/or the selective neutrality of the loci investigated.

Genetic and morphologic variation in 'Phyllodoce empetriformis' and 'P. glanduliflora' (Ericaceae) in Mount Rainier National Park, Washington

USGS Publications Warehouse

Rochefort, Regina M.; Peterson, D.L.

2001-01-01

Genetic and morphological diversity of Phyllodoce empetriformis (Sw.) D. Don and Phyllodoce glanduliflora (hook.) Cov. were surveyed in Mount Rainier National Park in the Cascade Mountains of Washington State. Paired populations at high and low elevations were sampled at three study areas between 1720- and 2451-m elevation. Allozyme analysis of four polymorphic loci indicates high levels of genetic diversity within populations (P. empetriformis = 94.2% and P. glanduliflora = 93.4% of total diversity) and significant differences in allele frequencies among populations and study areas. Individual populations are composed of multiple clones with high ratios of local to widespread genotypes. The proportion of distinguishable clones ranges from 32 to 83% within individual populations. Within individual populations, 18-67% of genotypes were restricted to one population. Patterns of morphologic variation, estimated through measurements of leaf width, leaf length, stem extension, and plant height paralleled those displayed by allozyme analysis. Significant differences were found in leaf width and stem length for P. empetriformis and among greenhouse populations for leaf width (P. empetriformis) and leaf length (P. glanduliflora). Species conservation strategies for Phyllodoce should concentrate on the maintenance of within-population levels of diversity, protection of adjacent populations, and protection of safe sites for recruitment of new populations.

THE OCCURRENCE OF HIGH LEVELS OF LIPIDS IN FUNDULUS HETERCLITUS FROM A HIGHLY PCB CONTAIMINATED SITE

EPA Science Inventory

A population model constructed by Munns et al. (1997) for Fundulus heteroclitus predicts that populations in severely impacted ecosystems such as New Bedford Harbor, a highly PCB contaminated Superfund site, should be under severe stress. However, cursory assessment of the fish p...

Adaptation of the Long-Lived Monocarpic Perennial Saxifraga longifolia to High Altitude1[OPEN

PubMed Central

Morales, Melanie; Fleta-Soriano, Eva; Garcia, Maria B.

2016-01-01

Global change is exerting a major effect on plant communities, altering their potential capacity for adaptation. Here, we aimed at unveiling mechanisms of adaptation to high altitude in an endemic long-lived monocarpic, Saxifraga longifolia, by combining demographic and physiological approaches. Plants from three altitudes (570, 1100, and 2100 m above sea level [a.s.l.]) were investigated in terms of leaf water and pigment contents, and activation of stress defense mechanisms. The influence of plant size on physiological performance and mortality was also investigated. Levels of photoprotective molecules (α-tocopherol, carotenoids, and anthocyanins) increased in response to high altitude (1100 relative to 570 m a.s.l.), which was paralleled by reduced soil and leaf water contents and increased ABA levels. The more demanding effect of high altitude on photoprotection was, however, partly abolished at very high altitudes (2100 m a.s.l.) due to improved soil water contents, with the exception of α-tocopherol accumulation. α-Tocopherol levels increased progressively at increasing altitudes, which paralleled with reductions in lipid peroxidation, thus suggesting plants from the highest altitude effectively withstood high light stress. Furthermore, mortality of juveniles was highest at the intermediate population, suggesting that drought stress was the main environmental driver of mortality of juveniles in this rocky plant species. Population structure and vital rates in the high population evidenced lower recruitment and mortality in juveniles, activation of clonal growth, and absence of plant size-dependent mortality. We conclude that, despite S. longifolia has evolved complex mechanisms of adaptation to altitude at the cellular, whole-plant and population levels, drought events may drive increased mortality in the framework of global change. PMID:27440756

Systemic effects of arctic pollutants in beluga whales indicated by CYP1A1 expression.

PubMed

Wilson, Joanna Y; Cooke, Suzy R; Moore, Michael J; Martineau, Daniel; Mikaelian, Igor; Metner, Donald A; Lockhart, W Lyle; Stegeman, John J

2005-11-01

Cytochrome P450 1A1 (CYP1A1) is induced by exposure to polycyclic aromatic hydrocarbons (PAHs) and planar halogenated aromatic hydrocarbons (PHAHs) such as non-ortho polychlorinated biphenyls (PCBs). In this study, we examined CYP1A1 protein expression immunohistochemically in multiple organs of beluga whales from two locations in the Arctic and from the St. Lawrence estuary. These beluga populations have some of the lowest (Arctic sites) and highest (St. Lawrence estuary) concentrations of PCBs in blubber of all cetaceans. Samples from these populations might be expected to have different contaminant-induced responses, reflecting their different exposure histories. The pattern and extent of CYP1A1 staining in whales from all three locations were similar to those seen in animal models in which CYP1A has been highly induced, indicating a high-level expression in these whales. CYP1A1 induction has been related to toxic effects of PHAHs or PAHs in some species. In St. Lawrence beluga, the high level of CYP1A1 expression coupled with high levels of contaminants (including CYP1A1 substrates, e.g., PAH procarcinogens potentially activated by CYP1A1) indicates that CYP1A1 could be involved in the development of neoplastic lesions seen in the St. Lawrence beluga population. The systemic high-level expression of CYP1A1 in Arctic beluga suggests that effects of PAHs or PHAHs may be expected in Arctic populations, as well. The high-level expression of CYP1A1 in the Arctic beluga suggests that this species is highly sensitive to CYP1A1 induction by aryl hydrocarbon receptor agonists.

Adaptation of the Long-Lived Monocarpic Perennial Saxifraga longifolia to High Altitude.

PubMed

Munné-Bosch, Sergi; Cotado, Alba; Morales, Melanie; Fleta-Soriano, Eva; Villellas, Jesús; Garcia, Maria B

2016-10-01

Global change is exerting a major effect on plant communities, altering their potential capacity for adaptation. Here, we aimed at unveiling mechanisms of adaptation to high altitude in an endemic long-lived monocarpic, Saxifraga longifolia, by combining demographic and physiological approaches. Plants from three altitudes (570, 1100, and 2100 m above sea level [a.s.l.]) were investigated in terms of leaf water and pigment contents, and activation of stress defense mechanisms. The influence of plant size on physiological performance and mortality was also investigated. Levels of photoprotective molecules (α-tocopherol, carotenoids, and anthocyanins) increased in response to high altitude (1100 relative to 570 m a.s.l.), which was paralleled by reduced soil and leaf water contents and increased ABA levels. The more demanding effect of high altitude on photoprotection was, however, partly abolished at very high altitudes (2100 m a.s.l.) due to improved soil water contents, with the exception of α-tocopherol accumulation. α-Tocopherol levels increased progressively at increasing altitudes, which paralleled with reductions in lipid peroxidation, thus suggesting plants from the highest altitude effectively withstood high light stress. Furthermore, mortality of juveniles was highest at the intermediate population, suggesting that drought stress was the main environmental driver of mortality of juveniles in this rocky plant species. Population structure and vital rates in the high population evidenced lower recruitment and mortality in juveniles, activation of clonal growth, and absence of plant size-dependent mortality. We conclude that, despite S. longifolia has evolved complex mechanisms of adaptation to altitude at the cellular, whole-plant and population levels, drought events may drive increased mortality in the framework of global change. © 2016 American Society of Plant Biologists. All Rights Reserved.

Systemic Effects of Arctic Pollutants in Beluga Whales Indicated by CYP1A1 Expression

PubMed Central

Wilson, Joanna Y.; Cooke, Suzy R.; Moore, Michael J.; Martineau, Daniel; Mikaelian, Igor; Metner, Donald A.; Lockhart, W. Lyle; Stegeman, John J.

2005-01-01

Cytochrome P450 1A1 (CYP1A1) is induced by exposure to polycyclic aromatic hydrocarbons (PAHs) and planar halogenated aromatic hydrocarbons (PHAHs) such as non-ortho polychlorinated biphenyls (PCBs). In this study, we examined CYP1A1 protein expression immunohistochemically in multiple organs of beluga whales from two locations in the Arctic and from the St. Lawrence estuary. These beluga populations have some of the lowest (Arctic sites) and highest (St. Lawrence estuary) concentrations of PCBs in blubber of all cetaceans. Samples from these populations might be expected to have different contaminant-induced responses, reflecting their different exposure histories. The pattern and extent of CYP1A1 staining in whales from all three locations were similar to those seen in animal models in which CYP1A has been highly induced, indicating a high-level expression in these whales. CYP1A1 induction has been related to toxic effects of PHAHs or PAHs in some species. In St. Lawrence beluga, the high level of CYP1A1 expression coupled with high levels of contaminants (including CYP1A1 substrates, e.g., PAH procarcinogens potentially activated by CYP1A1) indicates that CYP1A1 could be involved in the development of neoplastic lesions seen in the St. Lawrence beluga population. The systemic high-level expression of CYP1A1 in Arctic beluga suggests that effects of PAHs or PHAHs may be expected in Arctic populations, as well. The high-level expression of CYP1A1 in the Arctic beluga suggests that this species is highly sensitive to CYP1A1 induction by aryl hydrocarbon receptor agonists. PMID:16263517

Geographical distance and barriers explain population genetic patterns in an endangered island perennial

PubMed Central

Dias, Elisabete F.; Moura, M.; Schaefer, H.; Silva, Luís

2016-01-01

Island plants are frequently used as model systems in evolutionary biology to understand factors that might explain genetic diversity and population differentiation levels. Theory suggests that island plants should have lower levels of genetic diversity than their continental relatives, but this hypothesis has been rejected in several recent studies. In the Azores, the population level genetic diversity is generally low. However, like in most island systems, there are high levels of genetic differentiation between different islands. The Azores lettuce, Lactuca watsoniana, is an endangered Asteraceae with small population sizes. Therefore, we expect to find a lower level of genetic diversity than in the other more common endemic Asteraceae. The intra- and interpopulation genetic structure and diversity of L. watsoniana was assessed using eight newly developed microsatellite markers. We included 135 individuals, from all 13 known populations in the study. Because our microsatellite results suggested that the species is tetraploid, we analysed the microsatellite data (i) in codominant format using PolySat (Principal Coordinate Analysis, PCoA) and SPAgedi (genetic diversity indexes) and (ii) in dominant format using Arlequin (AMOVA) and STRUCTURE (Bayesian genetic cluster analysis). A total of 129 alleles were found for all L. watsoniana populations. In contrast to our expectations, we found a high level of intrapopulation genetic diversity (total heterozigosity = 0.85; total multilocus average proportion of private alleles per population = 26.5 %, Fis = −0.19). Our results show the existence of five well-defined genetic groups, one for each of the three islands São Miguel, Terceira and Faial, plus two groups for the East and West side of Pico Island (Fst = 0.45). The study revealed the existence of high levels of genetic diversity, which should be interpreted taking into consideration the ploidy level of this rare taxon. PMID:27742648

Blending local scale information for developing agricultural resilience in Ethiopia

USGS Publications Warehouse

Funk, Christopher C.; Husak, Gregory; Mahiny, A.S; Eilerts, Gary; Rowland, James

2013-01-01

This brief article looks at the intersection of climate, land cover/land use, and population trends in the world's most food insecure country, Ethiopia. As a result of warming in the Indian and Western Pacific oceans, Ethiopia has experienced substantial drying over the past 20 years. We intersect the spatial pattern of this drying with high resolution climatologies, maps of agricultural expansion, population data, and socioeconomic livelihoods information to suggest that the coincidence of drying and agricultural expansion in south-central Ethiopia is likely adversely affecting a densely populated region with high levels of poverty and low wage levels.

Genetic analysis of the Venezuelan Criollo horse.

PubMed

Cothran, E G; Canelon, J L; Luis, C; Conant, E; Juras, R

2011-10-07

Various horse populations in the Americas have an origin in Spain; they are remnants of the first livestock introduced to the continent early in the colonial period (16th and 17th centuries). We evaluated genetic variability within the Venezuelan Criollo horse and its relationship with other horse breeds. We observed high levels of genetic diversity within the Criollo breed. Significant population differentiation was observed between all South American breeds. The Venezuelan Criollo horse showed high levels of genetic diversity, and from a conservation standpoint, there is no immediate danger of losing variation unless there is a large drop in population size.

Discovery of SNPs for individual identification by reduced representation sequencing of moose (Alces alces).

PubMed

Blåhed, Ida-Maria; Königsson, Helena; Ericsson, Göran; Spong, Göran

2018-01-01

Monitoring of wild animal populations is challenging, yet reliable information about population processes is important for both management and conservation efforts. Access to molecular markers, such as SNPs, enables population monitoring through genotyping of various DNA sources. We have developed 96 high quality SNP markers for individual identification of moose (Alces alces), an economically and ecologically important top-herbivore in boreal regions. Reduced representation libraries constructed from 34 moose were high-throughput de novo sequenced, generating nearly 50 million read pairs. About 50 000 stacks of aligned reads containing one or more SNPs were discovered with the Stacks pipeline. Several quality criteria were applied on the candidate SNPs to find markers informative on the individual level and well representative for the population. An empirical validation by genotyping of sequenced individuals and additional moose, resulted in the selection of a final panel of 86 high quality autosomal SNPs. Additionally, five sex-specific SNPs and five SNPs for sympatric species diagnostics are included in the panel. The genotyping error rate was 0.002 for the total panel and probability of identities were low enough to separate individuals with high confidence. Moreover, the autosomal SNPs were highly informative also for population level analyses. The potential applications of this SNP panel are thus many including investigations of population size, sex ratios, relatedness, reproductive success and population structure. Ideally, SNP-based studies could improve today's population monitoring and increase our knowledge about moose population dynamics.

Population structure of Aphis spiraecola (Hemiptera: Aphididae) on pear trees in China identified using microsatellites.

PubMed

Cao, Jinjun; Li, Jie; Niu, Jianqun; Liu, Xiaoxia; Zhang, Qingwen

2012-04-01

The spiraea aphid (Aphis spiraecola Patch) is a primary pest of fruit trees, particularly pear trees in China. Despite the economic importance of this pest, little is known about its genetic structure or its patterns of dispersal at local and regional scales; however, knowledge of these characteristics is important for establishing effective control strategies for this pest. The genetic variability of 431 individuals from 21 populations on pear trees in China was investigated using eight polymorphic microsatellite loci. The high polymorphism of these markers was evident from the expected heterozygosity value (He = 0.824) and the Polymorphism Information Content (PIC = 0.805), indicating that the spiraea aphid maintains a high level of genetic diversity. The analysis of molecular variance revealed a middle level of population differentiation (F(ST) = 0.1478) among A. spiraecola populations. This result is consistent with the results of the STRUCTURE analysis (K = 3), the unweighted pair-group method with arithmetic average tree and the Mantel test (r = 0.6392; P < 0.05). Our results indicate high levels of genetic exchange in the spiraea aphid, possibly facilitated by geography and climate. Our findings emphasize the importance of considering regional differences in studies of population structure, even when strong isolation-by-distance influences the genetic population structure of species.

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

USGS Publications Warehouse

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.

Hubby and Lewontin on Protein Variation in Natural Populations: When Molecular Genetics Came to the Rescue of Population Genetics.

PubMed

Charlesworth, Brian; Charlesworth, Deborah; Coyne, Jerry A; Langley, Charles H

2016-08-01

The 1966 GENETICS papers by John Hubby and Richard Lewontin were a landmark in the study of genome-wide levels of variability. They used the technique of gel electrophoresis of enzymes and proteins to study variation in natural populations of Drosophila pseudoobscura, at a set of loci that had been chosen purely for technical convenience, without prior knowledge of their levels of variability. Together with the independent study of human populations by Harry Harris, this seminal study provided the first relatively unbiased picture of the extent of genetic variability in protein sequences within populations, revealing that many genes had surprisingly high levels of diversity. These papers stimulated a large research program that found similarly high electrophoretic variability in many different species and led to statistical tools for interpreting the data in terms of population genetics processes such as genetic drift, balancing and purifying selection, and the effects of selection on linked variants. The current use of whole-genome sequences in studies of variation is the direct descendant of this pioneering work. Copyright © 2016 by the Genetics Society of America.

Genetic diversity and structure of the threatened species Sinopodophyllum hexandrum (Royle) Ying.

PubMed

Liu, W; Wang, J; Yin, D X; Yang, M; Wang, P; Han, Q S; Ma, Q Q; Liu, J J; Wang, J X

2016-06-10

Sinopodophyllum hexandrum is an important medicinal plant that has been listed as an endangered species, making the conservation of its genetic diversity a priority. Therefore, the genetic diversity and population structure of S. hexandrum was investigated through inter-simple sequence repeat analysis of eight natural populations. Eleven selected primers generated 141 discernible fragments. The percentage of polymorphic bands was 37.59% at the species level, and 7.66-24.32% at the population level. Genetic diversity of S. hexandrum was low within populations (average HE = 0.0366), but higher at the species level (HE = 0.0963). Clear structure and high genetic differentiation were detected between populations using unweighted pair groups mean arithmetic and principle coordinate analysis. Clustering approaches clustered the eight sampled populations into three major groups, and AMOVA confirmed there to be significant variation between populations (63.27%). Genetic differentiation may have arisen through limited gene flow (Nm = 0.3317) in this species. Isolation by distance among populations was determined by comparing genetic distance versus geographical distance using the Mantel test. The results revealed no correlation between spatial pattern and geographic location. Given the low within-population genetic diversity, high differentiation among populations, and the increasing anthropogenic pressure on this species, in situ conservation measures, in addition to sampling and ex situ preservation, are recommended to preserve S. hexandrum populations and to retain their genetic diversity.

Estimating risks of heat strain by age and sex: a population-level simulation model.

PubMed

Glass, Kathryn; Tait, Peter W; Hanna, Elizabeth G; Dear, Keith

2015-05-18

Individuals living in hot climates face health risks from hyperthermia due to excessive heat. Heat strain is influenced by weather exposure and by individual characteristics such as age, sex, body size, and occupation. To explore the population-level drivers of heat strain, we developed a simulation model that scales up individual risks of heat storage (estimated using Myrup and Morgan's man model "MANMO") to a large population. Using Australian weather data, we identify high-risk weather conditions together with individual characteristics that increase the risk of heat stress under these conditions. The model identifies elevated risks in children and the elderly, with females aged 75 and older those most likely to experience heat strain. Risk of heat strain in males does not increase as rapidly with age, but is greatest on hot days with high solar radiation. Although cloudy days are less dangerous for the wider population, older women still have an elevated risk of heat strain on hot cloudy days or when indoors during high temperatures. Simulation models provide a valuable method for exploring population level risks of heat strain, and a tool for evaluating public health and other government policy interventions.

Population genetics of Ceratitis capitata in South Africa: implications for dispersal and pest management.

PubMed

Karsten, Minette; van Vuuren, Bettine Jansen; Barnaud, Adeline; Terblanche, John S

2013-01-01

The invasive Mediterranean fruit fly (medfly), Ceratitis capitata, is one of the major agricultural and economical pests globally. Understanding invasion risk and mitigation of medfly in agricultural landscapes requires knowledge of its population structure and dispersal patterns. Here, estimates of dispersal ability are provided in medfly from South Africa at three spatial scales using molecular approaches. Individuals were genotyped at 11 polymorphic microsatellite loci and a subset of individuals were also sequenced for the mitochondrial cytochrome oxidase subunit I gene. Our results show that South African medfly populations are generally characterized by high levels of genetic diversity and limited population differentiation at all spatial scales. This suggests high levels of gene flow among sampling locations. However, natural dispersal in C. capitata has been shown to rarely exceed 10 km. Therefore, documented levels of high gene flow in the present study, even between distant populations (>1600 km), are likely the result of human-mediated dispersal or at least some form of long-distance jump dispersal. These findings may have broad applicability to other global fruit production areas and have significant implications for ongoing pest management practices, such as the sterile insect technique.

A POPULATION MEMETICS APPROACH TO CULTURAL EVOLUTION IN CHAFFINCH SONG: DIFFERENTIATION AMONG POPULATIONS.

PubMed

Lynch, Alejandro; Baker, Allan J

1994-04-01

We investigated cultural evolution in populations of common chaffinches (Fringilla coelebs) in the Atlantic islands (Azores, Madeira, and Canaries) and neighboring continental regions (Morocco and Iberia) by employing a population-memetic approach. To quantify differentiation, we used the concept of a song meme, defined as a single syllable or a series of linked syllables capable of being transmitted. The levels of cultural differentiation are higher among the Canaries populations than among the Azorean ones, even though the islands are on average closer to each other geographically. This is likely the result of reduced levels of migration, lower population sizes, and bottlenecks (possibly during the colonization of these populations) in the Canaries; all these factors produce a smaller effective population size and therefore accentuate the effects of differentiation by random drift. Significant levels of among-population differentiation in the Azores, in spite of substantial levels of migration, attest to the differentiating effects of high mutation rates of memes, which allow the accumulation of new mutants in different populations before migration can disperse them throughout the entire region. © 1994 The Society for the Study of Evolution.

Incorporating population-level variation in thermal performance into predictions of geographic range shifts.

PubMed

Angert, Amy L; Sheth, Seema N; Paul, John R

2011-11-01

Determining how species' geographic ranges are governed by current climates and how they will respond to rapid climatic change poses a major biological challenge. Geographic ranges are often spatially fragmented and composed of genetically differentiated populations that are locally adapted to different thermal regimes. Tradeoffs between different aspects of thermal performance, such as between tolerance to high temperature and tolerance to low temperature or between maximal performance and breadth of performance, suggest that the performance of a given population will be a subset of that of the species. Therefore, species-level projections of distribution might overestimate the species' ability to persist at any given location. However, current approaches to modeling distributions often do not consider variation among populations. Here, we estimated genetically-based differences in thermal performance curves for growth among 12 populations of the scarlet monkeyflower, Mimulus cardinalis, a perennial herb of western North America. We inferred the maximum relative growth rate (RGR(max)), temperature optimum (T(opt)), and temperature breadth (T(breadth)) for each population. We used these data to test for tradeoffs in thermal performance, generate mechanistic population-level projections of distribution under current and future climates, and examine how variation in aspects of thermal performance influences forecasts of range shifts. Populations differed significantly in RGR(max) and had variable, but overlapping, estimates of T(opt) and T(breadth). T(opt) declined with latitude and increased with temperature of origin, consistent with tradeoffs between performances at low temperatures versus those at high temperatures. Further, T(breadth) was negatively related to RGR(max), as expected for a specialist-generalist tradeoff. Parameters of the thermal performance curve influenced properties of projected distributions. For both current and future climates, T(opt) was negatively related to latitudinal position, while T(breadth) was positively related to projected range size. The magnitude and direction of range shifts also varied with T(opt) and T(breadth), but sometimes in unexpected ways. For example, the fraction of habitat remaining suitable increased with T(opt) but decreased with T(breadth). Northern limits of all populations were projected to shift north, but the magnitude of shift decreased with T(opt) and increased with T(breadth). Median latitude was projected to shift north for populations with high T(breadth) and low T(opt), but south for populations with low T(breadth) and high T(opt). Distributions inferred by integrating population-level projections did not differ from a species-level projection that ignored variation among populations. However, the species-level approach masked the potential array of divergent responses by populations that might lead to genotypic sorting within the species' range. Thermal performance tradeoffs among populations within the species' range had important, but sometimes counterintuitive, effects on projected responses to climatic change. © The Author 2011. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved.

The paternal ancestry of Uttarakhand does not imitate the classical caste system of India.

PubMed

Negi, Neetu; Tamang, Rakesh; Pande, Veena; Sharma, Amrita; Shah, Anish; Reddy, Alla G; Vishnupriya, Satti; Singh, Lalji; Chaubey, Gyaneshwer; Thangaraj, Kumarasamy

2016-02-01

Although, there have been rigorous research on the Indian caste system by several disciplines, it is still one of the most controversial socioscientific topic. Previous genetic studies on the subcontinent have supported a classical hierarchal sharing of genetic component by various castes of India. In the present study, we have used high-resolution mtDNA and Y chromosomal markers to characterize the genetic structuring of the Uttarakhand populations in the context of neighboring regions. Furthermore, we have tested whether the genetic structuring of caste populations at different social levels of this region, follow the classical chaturvarna system. Interestingly, we found that this region showed a high level of variation for East Eurasian ancestry in both maternal and paternal lines of descent. Moreover, the intrapopulation comparison showed a high level of heterogeneity, likely because of different caste hierarchy, interpolated on asymmetric admixture of populations inhabiting on both sides of the Himalayas.

Measurement of the photoionization cross section from the laser-populated 3D metastable levels in barium

NASA Technical Reports Server (NTRS)

Carlsten, J. L.; Mcilrath, T. J.; Parkinson, W. H.

1974-01-01

Measurements of the absolute photoionization cross section from the 6s5d 3D metastable level of barium are presented. The 3D levels were selectively populated with a high-power tuneable dye laser. The number density was determined by observing the resulting depopulation of the ground state when pumping occurred.

Dispersal-mediated effect of microhabitat availability and density dependence determine population dynamics of a forest floor web spider.

PubMed

Takada, Mayura B; Miyashita, Tadashi

2014-09-01

Landscapes in nature can be viewed as a continuum of small total habitable area with high fragmentation to widely spreading habitats. The dispersal-mediated rescue effect predominates in the former landscapes, while classical density-dependent processes generally prevail in widely spread habitats. A similar principle should be applied to populations of organisms utilizing microhabitats in limited supply. To test this hypothesis, we examined the population dynamics of a web spider, Neriene brongersmai, in 16 populations with varying degrees of microhabitat availability, and we explored whether: (i) high microhabitat availability improves survival rate during density-independent movement, while the resultant high density reduces survival rate in a density-dependent manner; and (ii) temporal population stability increases with microhabitat availability at the population level. Furthermore, we conducted two types of field experiments to verify whether high microhabitat availability actually reduces mortality associated with web-site movement. Field observations revealed that demographic change in N. brongersmai populations was affected by three factors at different stages, namely the microhabitat limitation from the early to late juvenile stages, the density dependence from the late juvenile to adult stages and the food limitation from the adult to the next early juvenile stages. In addition, there was a tendency for a positive association between population stability and microhabitat availability at the population level. A small-scale experiment, where the frequency of spider web relocation was equalized artificially, revealed that high microhabitat availability elevated the survival rate during a movement event between web-sites. The larger spatiotemporal scale experiment also revealed an improved spider survival rate following treatment with high microhabitat availability, even though spider density was kept at a relatively low level. The population dynamics of N. brongersmai can be determined primarily by density-independent processes based on web-site fragmentation and density-dependent processes driven by interference competition. We conclude that depending on the amount of habitat resources, the relative importance of the two contrasting paradigms-equilibrium and non-equilibrium-appears to vary, even within a particular system. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

A reduced number of mtSNPs saturates mitochondrial DNA haplotype diversity of worldwide population groups.

PubMed

Salas, Antonio; Amigo, Jorge

2010-05-03

The high levels of variation characterising the mitochondrial DNA (mtDNA) molecule are due ultimately to its high average mutation rate; moreover, mtDNA variation is deeply structured in different populations and ethnic groups. There is growing interest in selecting a reduced number of mtDNA single nucleotide polymorphisms (mtSNPs) that account for the maximum level of discrimination power in a given population. Applications of the selected mtSNP panel range from anthropologic and medical studies to forensic genetic casework. This study proposes a new simulation-based method that explores the ability of different mtSNP panels to yield the maximum levels of discrimination power. The method explores subsets of mtSNPs of different sizes randomly chosen from a preselected panel of mtSNPs based on frequency. More than 2,000 complete genomes representing three main continental human population groups (Africa, Europe, and Asia) and two admixed populations ("African-Americans" and "Hispanics") were collected from GenBank and the literature, and were used as training sets. Haplotype diversity was measured for each combination of mtSNP and compared with existing mtSNP panels available in the literature. The data indicates that only a reduced number of mtSNPs ranging from six to 22 are needed to account for 95% of the maximum haplotype diversity of a given population sample. However, only a small proportion of the best mtSNPs are shared between populations, indicating that there is not a perfect set of "universal" mtSNPs suitable for all population contexts. The discrimination power provided by these mtSNPs is much higher than the power of the mtSNP panels proposed in the literature to date. Some mtSNP combinations also yield high diversity values in admixed populations. The proposed computational approach for exploring combinations of mtSNPs that optimise the discrimination power of a given set of mtSNPs is more efficient than previous empirical approaches. In contrast to precedent findings, the results seem to indicate that only few mtSNPs are needed to reach high levels of discrimination power in a population, independently of its ancestral background.

A Reduced Number of mtSNPs Saturates Mitochondrial DNA Haplotype Diversity of Worldwide Population Groups

PubMed Central

Salas, Antonio; Amigo, Jorge

2010-01-01

Background The high levels of variation characterising the mitochondrial DNA (mtDNA) molecule are due ultimately to its high average mutation rate; moreover, mtDNA variation is deeply structured in different populations and ethnic groups. There is growing interest in selecting a reduced number of mtDNA single nucleotide polymorphisms (mtSNPs) that account for the maximum level of discrimination power in a given population. Applications of the selected mtSNP panel range from anthropologic and medical studies to forensic genetic casework. Methodology/Principal Findings This study proposes a new simulation-based method that explores the ability of different mtSNP panels to yield the maximum levels of discrimination power. The method explores subsets of mtSNPs of different sizes randomly chosen from a preselected panel of mtSNPs based on frequency. More than 2,000 complete genomes representing three main continental human population groups (Africa, Europe, and Asia) and two admixed populations (“African-Americans” and “Hispanics”) were collected from GenBank and the literature, and were used as training sets. Haplotype diversity was measured for each combination of mtSNP and compared with existing mtSNP panels available in the literature. The data indicates that only a reduced number of mtSNPs ranging from six to 22 are needed to account for 95% of the maximum haplotype diversity of a given population sample. However, only a small proportion of the best mtSNPs are shared between populations, indicating that there is not a perfect set of “universal” mtSNPs suitable for all population contexts. The discrimination power provided by these mtSNPs is much higher than the power of the mtSNP panels proposed in the literature to date. Some mtSNP combinations also yield high diversity values in admixed populations. Conclusions/Significance The proposed computational approach for exploring combinations of mtSNPs that optimise the discrimination power of a given set of mtSNPs is more efficient than previous empirical approaches. In contrast to precedent findings, the results seem to indicate that only few mtSNPs are needed to reach high levels of discrimination power in a population, independently of its ancestral background. PMID:20454657

Which population groups should be targeted for cardiovascular prevention? A modelling study based on the Norwegian Hordaland Health Study (HUSK).

PubMed

Brekke, Mette; Rekdal, Magne; Straand, Jørund

2007-06-01

To assess level of cardiovascular risk factors in a non-selected, middle-aged population. To estimate the proportion target for risk intervention according to present guidelines and according to different cut-off levels for two risk algorithms. Population survey, modelling study. The Norwegian Hordaland Health Study (HUSK) 1997-99. A total of 22 289 persons born in 1950-57. Own and relatives' cardiovascular morbidity, antihypertensive and lipid-lowering treatment, smoking, blood pressure, cholesterol. Framingham and Systematic Coronary Risk Evaluation (SCORE) algorithms. The European guidelines on CVD prevention in clinical practice were applied to estimate size of risk groups. Some 9.7% of men and 7.6% of women had CVD, diabetes mellitus, a high level of one specific risk factor, or received lipid-lowering or antihypertensive treatment. Applying a SCORE (60 years) cut-off level at 5% to the rest of the population selected 52.4% of men and 0.8% of women into a primary prevention group, while a cut-off level at 8% included 22.0% and 0.06% respectively. A cut-off level for the Framingham score (60 years) of 20% selected 43.6% of men and 4.7% of women, while a cut-off level of 25% selected 25.6% of men and 1.8% of women. The findings illustrate how choices regarding risk estimation highly affect the size of the target population. Modelling studies are important when preparing guidelines, to address implications for resource allocation and risk of medicalization. The population share to be targeted for primary prevention ought to be estimated, including the impact of various cut-off points for risk algorithms on the size of the risk population.

The impact of new transportation modes on population distribution in Jing-Jin-Ji region of China

PubMed Central

Wang, Lizhe; Chen, Lajiao

2018-01-01

This paper conducts a novel study in China’s Jing-Jin-Ji region to investigate the determinants of population distribution and short-term migration based on a comprehensive dataset including traditional census data, earth observation data, and emerging Internet data. Our results show that due to the high level of urbanization in this region, natural conditions are no longer the strongest determinants of population distribution. New transportation modes, such as high-speed rail, have arisen as a significant determinant of population distribution and short-term migration, particularly in large cities. Socio-economic factors such as GDP, investment, urbanization level, and technology, which are traditionally assumed to govern population distribution and short-term migration, have less influence although education still remains an important factor affecting population distribution. These findings will contribute valuable information to regional planning decision-making in the Jing-Jin-Ji region. PMID:29360105

First report of amitraz and cypermethrin resistance in Rhipicephalus sanguineus sensu lato infesting dogs in Mexico.

PubMed

Rodriguez-Vivas, R I; Ojeda-Chi, M M; Trinidad-Martinez, I; Bolio-González, M E

2017-03-01

Engorged female Rhipicephalus sanguineus sensu lato (Ixodida: Ixodidae) were collected from dogs in the state of Yucatán, Mexico. Fourteen tick populations were collected from dogs at seven veterinary clinics, four residential homes and three cattle farms. The larval immersion test was used in the progeny of collected adult females to test susceptibility to amitraz and cypermethrin. Dose-mortality regressions, 50% lethal concentrations (LC 50 ), confidence intervals and slope were estimated by probit analysis. For amitraz, 12 tick populations (85.7%) were classified as resistant and low inter-population variation in the phenotypic level of resistance was evident [resistance ratios (RRs) at LC 50 : 1.0-13.0]. For cypermethrin, 12 tick populations (85.7%) were classified as resistant and substantial inter-population variation in the phenotypic level of resistance was evident (RRs at LC 50 : 1.0-104.0). Thus, amitraz resistance in R. sanguineus s.l. is common, but generally occurs at low levels; however, alarmingly high levels of cypermethrin resistance are present in R. sanguineus s.l. populations in dogs in Yucatán, Mexico. The intensive use of both acaricides to control ectoparasites on dogs is likely to lead to more serious resistance problems that may cause high levels of control failure in the future. © 2016 The Royal Entomological Society.

Spatial and temporal aspects of the genetic structure of Juniperus communis populations.

PubMed

Merwe, M V; Winfield, M O; Arnold, G M; Parker, J S

2000-04-01

Juniperus communis is a dioecious, wind pollinated shrub or small tree that produces 'berries' (female cones) containing a small number of seeds that are thought to be dispersed by birds. The expectation, therefore, would be that populations of Juniper are genetically diverse with little structuring between them. In Britain, the species has two main centres of distribution: a highland zone in the north and west, in which populations are still large and sexually reproducing, and a southern zone on chalk downlands in which populations are small and fragmented and individuals suffer from a decline in fertility. Thus, one would expect the large sexually viable populations in the north to exhibit high levels of within-population genetic variation, while the declining southern populations would be genetically depauperate. The analysis of amplified fragment length polymorphisms (AFLPs) was used to test this hypothesis. Surprisingly, all populations studied showed high levels of genetic variation although there was clear structuring between populations. On the basis of the geographical structuring of the populations it was hypothesized that J. communis colonized Britain via three separate routes.

Incidence of elevated lipoprotein (a) levels in a large cohort of patients with cardiovascular disease.

PubMed

van Buuren, Frank; Horstkotte, Dieter; Knabbe, Cornelius; Hinse, Dennis; Mellwig, Klaus Peter

2017-03-01

Recently it has been demonstrated that elevated lipoprotein (a) (LPA) levels are associated with an increased risk of cardiovascular disease across multiple ethnic groups. However, there is only scanty data about the incidence of elevated LPA levels in different patient cohorts. As a consequence, we aimed to examine whether patients with elevated LPA levels might be seen more often in a cardiovascular center in comparison to the general population. We reviewed LPA concentrations of 52,898 consecutive patients who were admitted to our hospital between January 2004 and December 2014. We subdivided them into different groups according to their LPA levels. Data was compared to available information in medical literature. 26.4% of the patients had LPA levels >30 mg/dl which is in line with the data from literature. Mean level of LPA concentration in our study was twice as high in comparison to the general population (25.8% vs. 13.3%). 4.6% had LPA levels >98 mg/dl (general population <0.3%). In patients admitted to a cardiovascular center the proportion of LPA >30 mg/dl is comparable to the general population but mean levels over all are twice as high and the proportion of patients with LPA levels of >98 mg/dl is extremely higher.

Genetic diversity and population structure of an extremely endangered species: the world's largest Rhododendron.

PubMed

Wu, Fu Qin; Shen, Shi Kang; Zhang, Xin Jun; Wang, Yue Hua; Sun, Wei Bang

2014-12-04

Comprehensive studies on the genetic diversity and structure of endangered species are urgently needed to promote effective conservation and management activities. The big tree rhododendron, Rhododendron protistum var. giganteum, is a highly endangered species with only two known endemic populations in a small area in the southern part of Yunnan Province in China. Unfortunately, limited information is available regarding the population genetics of this species. Therefore, we conducted amplified fragment length polymorphism (AFLP) analysis to characterize the genetic diversity and variation of this species within and between remaining populations. Twelve primer combinations of AFLP produced 447 unambiguous and repetitious bands. Among these bands, 298 (66.67 %) were polymorphic. We found high genetic diversity at the species level (percentage of polymorphic loci = 66.67 %, h = 0.240, I = 0.358) and low genetic differentiation (Gst = 0.110) between the two populations. Gene flow between populations (Nm) was relatively high at 4.065. Analysis of molecular variance results revealed that 22 % of the genetic variation was partitioned between populations and 78 % of the genetic variation was within populations. The presence of moderate to high genetic diversity and low genetic differentiation in the two populations can be explained by life history traits, pollen dispersal and high gene flow (Nm = 4.065). Bayesian structure and principal coordinate analysis revealed that 56 sampled trees were clustered into two groups. Our results suggest that some rare and endangered species are able to maintain high levels of genetic diversity even at small population sizes. These results will assist with the design of conservation and management programmes, such as in situ and ex situ conservation, seed collection for germplasm conservation and reintroduction. Published by Oxford University Press on behalf of the Annals of Botany Company.

Urbanization and Mental Health in China: Linking the 2010 Population Census with a Cross-Sectional Survey.

PubMed

Chen, Juan; Chen, Shuo; Landry, Pierre F

2015-07-31

Along with the rapid urbanization in China, the state of mental health also receives growing attention. Empirical measures, however, have not been developed to assess the impact of urbanization on mental health and the dramatic spatial variations. Innovatively linking the 2010 Chinese Population Census with a 2011 national survey of urban residents, we first assess the impact of urbanization on depressive symptoms measured by the Center of Epidemiological Studies Depression Scale (CES-D) of 1288 survey respondents. We then retrieve county-level characteristics from the 2010 Chinese Population Census that match the individual characteristics in the survey, so as to create a profile of the "average person" for each of the 2869 counties or city districts, and predict a county-specific CES-D score. We use this county-specific CES-D score to compute the CES-D score for the urban population at the prefectural level, and to demonstrate the dramatic spatial variations in urbanization and mental health across China: highly populated cities along the eastern coast such as Shenyang and Shanghai show high CES-D scores, as do cities in western China with high population density and a high proportion of educated ethnic minorities.

High-altitude diving in river otters: coping with combined hypoxic stresses.

PubMed

Crait, Jamie R; Prange, Henry D; Marshall, Noah A; Harlow, Henry J; Cotton, Clark J; Ben-David, Merav

2012-01-15

River otters (Lontra canadensis) are highly active, semi-aquatic mammals indigenous to a range of elevations and represent an appropriate model for assessing the physiological responses to diving at altitude. In this study, we performed blood gas analyses and compared blood chemistry of river otters from a high-elevation (2357 m) population at Yellowstone Lake with a sea-level population along the Pacific coast. Comparisons of oxygen dissociation curves (ODC) revealed no significant difference in hemoglobin-oxygen (Hb-O(2)) binding affinity between the two populations - potentially because of demands for tissue oxygenation. Instead, high-elevation otters had greater Hb concentrations (18.7 g dl(-1)) than sea-level otters (15.6 g dl(-1)). Yellowstone otters displayed higher levels of the vasodilator nitric oxide (NO), and half the concentration of the serum protein albumin, possibly to compensate for increased blood viscosity. Despite compensation in several hematological and serological parameters, theoretical aerobic dive limits (ADL) were similar between high-elevation and sea-level otters because of the lower availability of O(2) at altitude. Our results suggest that recent disruptions to the Yellowstone Lake food web could be detrimental to otters because at this high elevation, constraints on diving may limit their ability to switch to prey in a deep-water environment.

Socioeconomic Differences in the Impact of HIV Infection on Workforce Participation in France in the Era of Highly Active Antiretroviral Therapy

PubMed Central

Dray-Spira, Rosemary; Gueguen, Alice; Ravaud, Jean-François; Lert, France

2007-01-01

Objectives. We sought to measure the difference in employment rates between HIV-seropositive and HIV-seronegative persons and to establish whether this difference varied according to the HIV-infected persons’ socioeconomic position as defined by education level. Methods. We used data from the VESPA (VIH: Enquête Sur les Personnes Atteintes) study, a large cross-sectional survey conducted among a nationally representative sample of 2932 HIV-infected patients in France. Age-, gender-, nationality-, and education-standardized employment rates were estimated with the French general population as the reference. The differences in employment rates with the general population were computed overall and according to education level. Results. Compared with that of the general population, the overall employment rate was 25% lower (95% confidence interval [CI]=16%, 32%) among HIV-infected patients diagnosed before 1994 and 9% lower (95% CI = 5%, 16%) among HIV-infected patients diagnosed from 1994 onward. The difference in employment rates with the general population was significantly higher among patients with a low education level. The employment rate of highly educated HIV-infected patients diagnosed from 1994 onward did not differ from that of the general population. Conclusions. HIV infection was associated with decreased workforce participation among those with a low education level but not among highly educated individuals. PMID:17267720

Genetic Diversity and Population Structure of the Rare and Endangered Plant Species Pulsatilla patens (L.) Mill in East Central Europe.

PubMed

Szczecińska, Monika; Sramko, Gabor; Wołosz, Katarzyna; Sawicki, Jakub

2016-01-01

Pulsatilla patens s.s. is a one of the most endangered plant species in Europe. The present range of this species in Europe is highly fragmented and the size of the populations has been dramatically reduced in the past 50 years. The rapid disappearance of P. patens localities in Europe has prompted the European Commission to initiate active protection of this critically endangered species. The aim of this study was to estimate the degree and distribution of genetic diversity within European populations of this endangered species. We screened 29 populations of P. patens using a set of six microsatellite primers. The results of our study indicate that the analyzed populations are characterized by low levels of genetic diversity (Ho = 0.005) and very high levels of inbreeding (FIS = 0.90). These results suggest that genetic erosion could be partially responsible for the lower fitness in smaller populations of this species. Private allelic richness was very low, being as low as 0.00 for most populations. Average genetic diversity over loci and mean number of alleles in P. patens populations were significantly correlated with population size, suggesting severe genetic drift. The results of AMOVA point to higher levels of variation within populations than between populations.The results of Structure and PCoA analyses suggest that the genetic structure of the studied P. patens populations fall into three clusters corresponding to geographical regions. The most isolated populations (mostly from Romania) formed a separate group with a homogeneous gene pool located at the southern, steppic part of the distribution range. Baltic, mostly Polish, populations fall into two genetic groups which were not fully compatible with their geographic distribution.Our results indicate the serious genetic depauperation of P. patens in the western part of its range, even hinting at an ongoing extinction vortex. Therefore, special conservation attention is required to maintain the populations of this highly endangered species of European Community interest.

A Virulent Strain of Deformed Wing Virus (DWV) of Honeybees (Apis mellifera) Prevails after Varroa destructor-Mediated, or In Vitro, Transmission

PubMed Central

Ryabov, Eugene V.; Wood, Graham R.; Fannon, Jessica M.; Moore, Jonathan D.; Bull, James C.; Chandler, Dave; Mead, Andrew; Burroughs, Nigel; Evans, David J.

2014-01-01

The globally distributed ectoparasite Varroa destructor is a vector for viral pathogens of the Western honeybee (Apis mellifera), in particular the Iflavirus Deformed Wing Virus (DWV). In the absence of Varroa low levels DWV occur, generally causing asymptomatic infections. Conversely, Varroa-infested colonies show markedly elevated virus levels, increased overwintering colony losses, with impairment of pupal development and symptomatic workers. To determine whether changes in the virus population were due Varroa amplifying and introducing virulent virus strains and/or suppressing the host immune responses, we exposed Varroa-naïve larvae to oral and Varroa-transmitted DWV. We monitored virus levels and diversity in developing pupae and associated Varroa, the resulting RNAi response and transcriptome changes in the host. Exposed pupae were stratified by Varroa association (presence/absence) and virus levels (low/high) into three groups. Varroa-free pupae all exhibited low levels of a highly diverse DWV population, with those exposed per os (group NV) exhibiting changes in the population composition. Varroa-associated pupae exhibited either low levels of a diverse DWV population (group VL) or high levels of a near-clonal virulent variant of DWV (group VH). These groups and unexposed controls (C) could be also discriminated by principal component analysis of the transcriptome changes observed, which included several genes involved in development and the immune response. All Varroa tested contained a diverse replicating DWV population implying the virulent variant present in group VH, and predominating in RNA-seq analysis of temporally and geographically separate Varroa-infested colonies, was selected upon transmission from Varroa, a conclusion supported by direct injection of pupae in vitro with mixed virus populations. Identification of a virulent variant of DWV, the role of Varroa in its transmission and the resulting host transcriptome changes furthers our understanding of this important viral pathogen of honeybees. PMID:24968198

Afghanistan.

PubMed

1983-05-01

In this discussion of Afghanistan, attention focuses on: the history of the country's demographic situation; the government's overall approach to population problems; population data systems and development planning; institutional arrangements for the integration of population within development objectives; population size, growth, and natural increase; morbidity and mortality; fertility; international migration; and spatial distribution. Only recently has there been a population census in the country; consequently, there has been relatively little reliable demographic information available, especially in a historical context. Afghanistan's total population was officially estimated at nearly 16 million in late 1967. According to UN estimates, the population totaled 8.3 million in 1960 and increased to 9.8 and 12.3 million in the following 2 decades to over 14 million by 1975. The rate of population growth, as estimated by the UN, is reported to have increased from 1.6% during 1950-55 to 2.4% by the following decade, reaching 2.9% during 1970-75. The crude birthrate declined slightly from 50.4 births/1000 during 1950-55 to 49.2 during 1970-75. The crude death rate declined from 34.6/1000 to 23.4 deaths/1000 during the same period. Although the rate of population growth is considered to be fairly high, the government does not perceive this as presenting a population problem for the country as a whole since the overall population density is relatively low (approximately 20 persons per square kilometer). A national statistical information system has been developed in Afghanistan over the past decades. The government has no explicit population policy, and a clear association between population and development issues has not been expressed. Policies in the area of population distribution indicate the government's concern with settlement and resettlement of certain segments of the population in connection with the overall economic and social development of sparsely populated areas. The government perceives the current rate of population growth as unsatisfactory because it is too high, but does not view this as presenting any particular population problem. Data on mortality rates based primarily on the 1979 census indicate a crude death rate of 22/1000 for the sedentary population. The government regards the levels off mortality to bbe unacceptable, and its official goal is to rapidly reduce mortality and morbidity. High priority is given to the prevention and treatment of morbidity among young children. The fertility levels are quite high, compared acceptability of these levels. Direct governmental support is givenn to the family planning program in terms of both access to informartion and family planning methods. Levels of immigration are not significant. No official policy concerning the spatial distribution of the population has been formulated.

Effects of population density on corticosterone levels of prairie voles in the field.

PubMed

Blondel, Dimitri V; Wallace, Gerard N; Calderone, Stefanie; Gorinshteyn, Marija; St Mary, Colette M; Phelps, Steven M

2016-01-01

High population density is often associated with increased levels of stress-related hormones, such as corticosterone (CORT). Prairie voles (Microtus ochrogaster) are a socially monogamous species known for their large population density fluctuations in the wild. Although CORT influences the social behavior of prairie voles in the lab, the effect of population density on CORT has not previously been quantified in this species in the field. We validated a non-invasive hormone assay for measuring CORT metabolites in prairie vole feces. We then used semi-natural enclosures to experimentally manipulate population density, and measured density effects on male space use and fecal CORT levels. Our enclosures generated patterns of space use and social interaction that were consistent with previous prairie vole field studies. Contrary to the positive relationship between CORT and density typical of other taxa, we found that lower population densities (80 animals/ha) produced higher fecal CORT than higher densities (240/ha). Combined with prior work in the lab and field, the data suggest that high prairie vole population densities indicate favorable environments, perhaps through reduced predation risk. Lastly, we found that field animals had lower fecal CORT levels than laboratory-living animals. The data emphasize the usefulness of prairie voles as models for integrating ecological, evolutionary, and mechanistic questions in social behavior. Copyright © 2015 Elsevier Inc. All rights reserved.

Population-Level Exposure to Particulate Air Pollution during Active Travel: Planning for Low-Exposure, Health-Promoting Cities

PubMed Central

Hankey, Steve; Lindsey, Greg; Marshall, Julian D.

2016-01-01

Background: Providing infrastructure and land uses to encourage active travel (i.e., bicycling and walking) are promising strategies for designing health-promoting cities. Population-level exposure to air pollution during active travel is understudied. Objectives: Our goals were a) to investigate population-level patterns in exposure during active travel, based on spatial estimates of bicycle traffic, pedestrian traffic, and particulate concentrations; and b) to assess how those exposure patterns are associated with the built environment. Methods: We employed facility–demand models (active travel) and land use regression models (particulate concentrations) to estimate block-level (n = 13,604) exposure during rush-hour (1600–1800 hours) in Minneapolis, Minnesota. We used the model-derived estimates to identify land use patterns and characteristics of the street network that are health promoting. We also assessed how exposure is correlated with indicators of health disparities (e.g., household income, proportion of nonwhite residents). Our work uses population-level rates of active travel (i.e., traffic flows) rather than the probability of walking or biking (i.e., “walkability” or “bikeability”) to assess exposure. Results: Active travel often occurs on high-traffic streets or near activity centers where particulate concentrations are highest (i.e., 20–42% of active travel occurs on blocks with high population-level exposure). Only 2–3% of blocks (3–8% of total active travel) are “sweet spots” (i.e., high active travel, low particulate concentrations); sweet spots are located a) near but slightly removed from the city-center or b) on off-street trails. We identified 1,721 blocks (~ 20% of local roads) where shifting active travel from high-traffic roads to adjacent low-traffic roads would reduce exposure by ~ 15%. Active travel is correlated with population density, land use mix, open space, and retail area; particulate concentrations were mostly unchanged with land use. Conclusions: Public health officials and urban planners may use our findings to promote healthy transportation choices. When designing health-promoting cities, benefits (physical activity) as well as hazards (air pollution) should be evaluated. Citation: Hankey S, Lindsey G, Marshall JD. 2017. Population-level exposure to particulate air pollution during active travel: planning for low-exposure, health-promoting cities. Environ Health Perspect 125:–534; http://dx.doi.org/10.1289/EHP442 PMID:27713109

Comparison of cancer incidence and mortality in three GDP per capita levels in China, 2013

PubMed Central

Yang, Zhixun; Zheng, Rongshou; Zhang, Siwei; Zeng, Hongmei; Xia, Changfa; Li, He; Wang, Li; Wang, Yanhong; Chen, Wanqing

2017-01-01

Objective In this research, the patterns of cancer incidence and mortality in areas with different gross domestic product per capita (GDPPC) levels in China were explored, using data from population-based cancer registries in 2013, collected by the National Central Cancer Registry (NCCR). Methods Data from 255 cancer registries were qualified and included in this analysis. Based on the GDPPC data of 2014, cities/counties were divided into 3 levels: high-, middle- and low-GDPPC areas, with 40,000 and 80,000 RMB per year as cut points. We calculated cancer incidences and mortalities in these three levels, stratified by gender and age group. The national population of the Fifth Census in 2000 and Segi’s population were applied for age-standardized rates. Results The crude incidence and mortality rates as well as age-standardized incidence rate (ASIR) showed positive associations with GDPPC level. The age-standardized mortality rate (ASMR) nevertheless showed a negative association with GDPPC level. The ASMR in high-, middle- and low-GDPPC areas was 103.12/100,000, 112.49/100,000 and 117.43/100,000, respectively. Lung cancer was by far the most common cancer in all three GDPPC levels. It was also the leading cause of cancer death, regardless of gender and GDPPC level. Negative associations with GDPPC level were found for the ASIRs of lung, stomach, esophageal and liver cancer, whereas colorectal and breast cancer showed positive associations. Except for breast cancer, the ASMRs of the other five cancers were always higher in middle- and low-GDPPC areas than in high-GDPPC areas. Conclusions The economic development is one of the main factors of the heavy cancer burden on Chinese population. It would be reasonable to implement cancer control strategies referring to the local GDPPC level. PMID:29142457

Comparison of cancer incidence and mortality in three GDP per capita levels in China, 2013.

PubMed

Yang, Zhixun; Zheng, Rongshou; Zhang, Siwei; Zeng, Hongmei; Xia, Changfa; Li, He; Wang, Li; Wang, Yanhong; Chen, Wanqing

2017-10-01

In this research, the patterns of cancer incidence and mortality in areas with different gross domestic product per capita (GDPPC) levels in China were explored, using data from population-based cancer registries in 2013, collected by the National Central Cancer Registry (NCCR). Data from 255 cancer registries were qualified and included in this analysis. Based on the GDPPC data of 2014, cities/counties were divided into 3 levels: high-, middle- and low-GDPPC areas, with 40,000 and 80,000 RMB per year as cut points. We calculated cancer incidences and mortalities in these three levels, stratified by gender and age group. The national population of the Fifth Census in 2000 and Segi's population were applied for age-standardized rates. The crude incidence and mortality rates as well as age-standardized incidence rate (ASIR) showed positive associations with GDPPC level. The age-standardized mortality rate (ASMR) nevertheless showed a negative association with GDPPC level. The ASMR in high-, middle- and low-GDPPC areas was 103.12/100,000, 112.49/100,000 and 117.43/100,000, respectively. Lung cancer was by far the most common cancer in all three GDPPC levels. It was also the leading cause of cancer death, regardless of gender and GDPPC level. Negative associations with GDPPC level were found for the ASIRs of lung, stomach, esophageal and liver cancer, whereas colorectal and breast cancer showed positive associations. Except for breast cancer, the ASMRs of the other five cancers were always higher in middle- and low-GDPPC areas than in high-GDPPC areas. The economic development is one of the main factors of the heavy cancer burden on Chinese population. It would be reasonable to implement cancer control strategies referring to the local GDPPC level.

Maintaining high rates of measles immunization in Africa.

PubMed

Lessler, J; Moss, W J; Lowther, S A; Cummings, D A T

2011-07-01

Supplementary immunization activities (SIAs) are important in achieving high levels of population immunity to measles virus. Using data from a 2006 survey of measles vaccination in Lusaka, Zambia, we developed a model to predict measles immunity following routine vaccination and SIAs, and absent natural infection. Projected population immunity was compared between the current programme and alternatives, including supplementing routine vaccination with a second dose, or SIAs at 1-, 2-, 3-, 4- and 5-year intervals. Current routine vaccination plus frequent SIAs could maintain high levels of population immunity in children aged <5 years, even if each frequent SIA has low coverage (e.g. ≥ 72% for bi-annual 60% coverage SIAs vs. ≥ 69% for quadrennial 95% coverage SIAs). A second dose at 12 months with current coverage could achieve 81% immunity. Circulating measles virus will only increase population immunity. Public health officials should consider frequent SIAs when resources for a two-dose strategy are unavailable.

A comprehensive assessment of mercury exposure in penguin populations throughout the Southern Hemisphere: Using trophic calculations to identify sources of population-level variation.

PubMed

Brasso, Rebecka L; Chiaradia, André; Polito, Michael J; Raya Rey, Andrea; Emslie, Steven D

2015-08-15

The wide geographic distribution of penguins (Order Sphenisciformes) throughout the Southern Hemisphere provided a unique opportunity to use a single taxonomic group as biomonitors of mercury among geographically distinct marine ecosystems. Mercury concentrations were compared among ten species of penguins representing 26 geographically distinct breeding populations. Mercury concentrations were relatively low (⩽2.00ppm) in feathers from 18/26 populations considered. Population-level differences in trophic level explained variation in mercury concentrations among Little, King, and Gentoo penguin populations. However, Southern Rockhopper and Magellanic penguins breeding on Staten Island, Tierra del Fuego, had the highest mercury concentrations relative to their conspecifics despite foraging at a lower trophic level. The concurrent use of stable isotope and mercury data allowed us to document penguin populations at the greatest risk of exposure to harmful concentrations of mercury as a result of foraging at a high trophic level or in geographic 'hot spots' of mercury availability. Copyright © 2015 Elsevier Ltd. All rights reserved.

Physical activity during work and leisure show contrasting associations with fear-avoidance beliefs: cross-sectional study among more than 10,000 wage earners of the general working population.

PubMed

Tribian, Annika; Vinstrup, Jonas; Sundstrup, Emil; Jay, Kenneth; Bös, Klaus; Andersen, Lars L

2018-01-26

The association between different types of physical activity and fear-avoidance beliefs remains unclear. This study investigates the association between work-related and leisure-time physical activity with fear-avoidance beliefs in the general working population. Currently employed wage earners (n=10,427) from the 2010 round of the Danish Work Environment Cohort Study replied to questions about work, lifestyle and health. General linear models controlling for lifestyle, psychosocial work factors, education, pain, medication-use and chronic diseases tested associations of work-related and leisure-time physical activity (explanatory variables) with fear-avoidance beliefs (outcome variable, scale 0-100). The level of fear-avoidance was 41.7 (SD 27.3), 38.0 (SD 26.9) and 54.3 (SD 27.7) among the general working population, a subgroup of pain-free individuals, and a subgroup with back disease, respectively. In the general working population, the level of fear-avoidance among those with low, moderate and high physical activity during leisure were 47 [95% confidence intervals (CI) 45-49], 44 (95% CI 42-46) and 43 (95% CI 41-45), and physical activity at work were 40 (95% CI 39-42), 44 (95% CI 42-46) and 49 (95% CI 48-51), respectively. Individuals with back disease and a high level of physical activity at work showed the overall highest level of fear-avoidance whereas pain-free individuals with a low level of physical activity at work showed the overall lowest level of fear-avoidance. Physical activity during work and leisure shows contrasting associations with fear-avoidance beliefs. While high physical activity during leisure is associated with lower levels, high physical activity at work is associated with higher levels of fear-avoidance. The present results may reflect some deeply rooted negative beliefs about pain and work in the population. On the societal level, campaigns may be a possible way forward as these have shown to improve beliefs about musculoskeletal pain and work.

Low C-Reactive Protein Levels in a Traditional West-African Population Living in a Malaria Endemic Area

PubMed Central

Eriksson, Ulrika K.; van Bodegom, David; May, Linda; Boef, Anna G. C.; Westendorp, Rudi G. J.

2013-01-01

Background C-reactive protein (CRP) levels are reported to be elevated in populations of African descent living in affluent environments compared to populations of European ancestry. However, the natural history of CRP levels in populations of African descent living under adverse environments remains largely unknown. Methods CRP levels were measured with a high sensitivity assay in 624 apparently healthy individuals who contributed blood as part of a study on innate immune responsiveness in a traditional Ghanaian population living under adverse environmental conditions in a malaria endemic area. As a comparison, we included CRP measurements from 2931 apparently healthy individuals from the Dutch population that were included in the same batch of CRP analyses. Associations between CRP and body mass index (BMI), immune responsiveness, and P. falciparum parasitaemia were investigated. Results In an age- and sex-adjusted model, CRP levels were 0.54 mg/L lower in the Ghanaian compared to the Dutch cohort (1.52 vs. 0.98 mg/L, p<0.001). When accounting for the substantially higher average BMI in the Dutch compared to the Ghanaians (25.6 vs. 18.4 kg/m2) the difference in CRP levels disappeared. BMI associated positively with CRP in the Dutch but not in the Ghanaians. In individuals with an acute phase response, CRP levels were higher in the Ghanaian compared to the Dutch cohort (24.6 vs. 17.3 mg/L, p = 0.04). Levels of CRP were positively related to immune responsiveness and P. falciparum parasitaemia (all p<0.001) among Ghanaians. Conclusions Our study demonstrates that West-Africans do not exhibit an inherently high inflammatory state. The role of genes, environment and gene-environment interaction in explaining reports of elevated CRP levels in populations of African ancestry when compared to other ethnicities living in affluent environments thus merits further investigation. PMID:23922912

Low C-reactive protein levels in a traditional West-African population living in a malaria endemic area.

PubMed

Eriksson, Ulrika K; van Bodegom, David; May, Linda; Boef, Anna G C; Westendorp, Rudi G J

2013-01-01

C-reactive protein (CRP) levels are reported to be elevated in populations of African descent living in affluent environments compared to populations of European ancestry. However, the natural history of CRP levels in populations of African descent living under adverse environments remains largely unknown. CRP levels were measured with a high sensitivity assay in 624 apparently healthy individuals who contributed blood as part of a study on innate immune responsiveness in a traditional Ghanaian population living under adverse environmental conditions in a malaria endemic area. As a comparison, we included CRP measurements from 2931 apparently healthy individuals from the Dutch population that were included in the same batch of CRP analyses. Associations between CRP and body mass index (BMI), immune responsiveness, and P. falciparum parasitaemia were investigated. In an age- and sex-adjusted model, CRP levels were 0.54 mg/L lower in the Ghanaian compared to the Dutch cohort (1.52 vs. 0.98 mg/L, p<0.001). When accounting for the substantially higher average BMI in the Dutch compared to the Ghanaians (25.6 vs. 18.4 kg/m(2)) the difference in CRP levels disappeared. BMI associated positively with CRP in the Dutch but not in the Ghanaians. In individuals with an acute phase response, CRP levels were higher in the Ghanaian compared to the Dutch cohort (24.6 vs. 17.3 mg/L, p = 0.04). Levels of CRP were positively related to immune responsiveness and P. falciparum parasitaemia (all p<0.001) among Ghanaians. Our study demonstrates that West-Africans do not exhibit an inherently high inflammatory state. The role of genes, environment and gene-environment interaction in explaining reports of elevated CRP levels in populations of African ancestry when compared to other ethnicities living in affluent environments thus merits further investigation.

LandScan 2016 High-Resolution Global Population Data Set

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bright, Edward A; Rose, Amy N; Urban, Marie L

The LandScan data set is a worldwide population database compiled on a 30" x 30" latitude/longitude grid. Census counts (at sub-national level) were apportioned to each grid cell based on likelihood coefficients, which are based on land cover, slope, road proximity, high-resolution imagery, and other data sets. The LandScan data set was developed as part of Oak Ridge National Laboratory (ORNL) Global Population Project for estimating ambient populations at risk.

Comprehensive view of the population history of Arabia as inferred by mtDNA variation.

PubMed

Černý, Viktor; Čížková, Martina; Poloni, Estella S; Al-Meeri, Ali; Mulligan, Connie J

2016-04-01

Genetic and archaeological research supports the theory that Arabia was the first region traversed by modern humans as they left Africa and dispersed throughout Eurasia. However, the role of Arabia from the initial migration out of Africa until more recent times is still unclear. We have generated 379 new hypervariable segment 1 (HVS-1) sequences from a range of geographic locations throughout Yemen. We compare these data to published HVS-1 sequences representing Arabia and neighboring regions to build a unique dataset of 186 populations and 14,290 sequences. We identify 4,563 haplotypes unevenly distributed across Arabia and neighboring regions. Arabia contains higher proportions of shared haplotypes than the regions with which it shares these haplotypes, suggesting high levels of migration through the region. Populations in Arabia show higher levels of population expansion than those in East Africa, but lower levels than the Near East, Middle East or India. Arabian populations also show very high levels of genetic variation that overlaps with variation from most other regions. We take a population genetics approach to provide a comprehensive view of the relationships of Arabian and neighboring populations. We show that Arabian populations share closest links to the Near East and North Africa, but have a more ancient origin with slower demographic growth and/or lower migration rates. Our conclusions are supported by phylogenetic studies but also suggest that recent migrations have erased signals of earlier events. © 2015 Wiley Periodicals, Inc.

Low-frequency Carbon Radio Recombination Lines. I. Calculations of Departure Coefficients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Salgado, F.; Morabito, L. K.; Oonk, J. B. R.

In the first paper of this series, we study the level population problem of recombining carbon ions. We focus our study on high quantum numbers, anticipating observations of carbon radio recombination lines to be carried out by the Low Frequency Array. We solve the level population equation including angular momentum levels with updated collision rates up to high principal quantum numbers. We derive departure coefficients by solving the level population equation in the hydrogenic approximation and including low-temperature dielectronic capture effects. Our results in the hydrogenic approximation agree well with those of previous works. When comparing our results including dielectronicmore » capture, we find differences that we ascribe to updates in the atomic physics (e.g., collision rates) and to the approximate solution method of the statistical equilibrium equations adopted in previous studies. A comparison with observations is discussed in an accompanying article, as radiative transfer effects need to be considered.« less

Colony patterning and collective hyphal growth of filamentous fungi

NASA Astrophysics Data System (ADS)

Matsuura, Shu

2002-11-01

Colony morphology of wild and mutant strains of Aspergillus nidulans at various nutrient and agar levels was investigated. Two types of colony patterning were found for these strains. One type produced uniform colonies at all nutrient and agar levels tested, and the other exhibited morphological change into disordered ramified colonies at low nutrient levels. Both types showed highly condensed compact colonies at high nutrient levels on low agar media that was highly diffusive. Disordered colonies were found to develop with low hyphal extension rates at low nutrient levels. To understand basic pattern selection rules, a colony model with three parameters, i.e., the initial nutrient level and the step length of nutrient random walk as the external parameters, and the frequency of nutrient uptake as an internal parameter, was constructed. At low nutrient levels, with decreasing nutrient uptake frequency under diffusive conditions, the model colony exhibited onsets of disordered ramification. Further, in the growth process of A. nidulans, reduction of hyphal extension rate due to a population effect of hyphae was found when hyphae form three-dimensional dense colonies, as compared to the case in which hyphal growth was restricted into two-dimensional space. A hyphal population effect was introduced in the colony model. Thickening of colony periphery due to the population effect became distinctive as the nutrient diffusion effect was raised at high nutrient levels with low hyphal growth rate. It was considered that colony patterning and onset of disorder were strongly governed by the combination of nutrient diffusion and hyphal growth rate.

Survival rates of female white-tailed deer on an industrial forest following a decline in population density

Treesearch

Shawn M. Crimmins; John W. Edwards; Patrick D. Keyser; James M. Crum; W. Mark Ford; Brad F. Miller; Tyler A. Campbell; Karl V. Miller

2013-01-01

With white-tailed deer (Odocoileus virginianus) populations at historically high levels throughout many North American forests, many current management activities are aimed at reducing deer populations. However, very little information exists on the ecology of low-density white-tailed deer populations or populations that have declined in density. We...

Insecticide resistance status of Aedes aegypti (L.) from Colombia.

PubMed

Fonseca-González, Idalyd; Quiñones, Martha L; Lenhart, Audrey; Brogdon, William G

2011-04-01

To evaluate the insecticide susceptibility status of Aedes aegypti (L.) in Colombia, and as part of the National Network of Insecticide Resistance Surveillance, 12 mosquito populations were assessed for resistance to pyrethroids, organophosphates and DDT. Bioassays were performed using WHO and CDC methodologies. The underlying resistance mechanisms were investigated through biochemical assays and RT-PCR. All mosquito populations were susceptible to malathion, deltamethrin and cyfluthrin, and highly resistant to DDT and etofenprox. Resistance to lambda-cyhalothrin, permethrin and fenitrothion ranged from moderate to high in some populations from Chocó and Putumayo states. In Antioquia state, the Santa Fe population was resistant to fenitrothion. Biochemical assays showed high levels of both cytochrome P450 monooxygenases (CYP) and non-specific esterases (NSE) in some of the fenitrothion- and pyrethroid-resistant populations. All populations showed high levels of glutathione-S-transferase (GST) activity. GSTe2 gene was found overexpressed in DDT-resistant populations compared with Rockefeller susceptible strain. Differences in insecticide resistance status were observed between insecticides and localities. Although the biochemical assay results suggest that CYP and NSE could play an important role in the pyrethroid and fenitrothion resistance detected, other mechanisms remain to be investigated, including knockdown resistance. Resistance to DDT was high in all populations, and GST activity is probably the main enzymatic mechanism associated with this resistance. The results of this study provide baseline data on insecticide resistance in Colombian A. aegypti populations, and will allow comparison of changes in susceptibility status in this vector over time. Copyright © 2011 Society of Chemical Industry.

Inferring genetic connectivity in real populations, exemplified by coastal and oceanic Atlantic cod.

PubMed

Spies, Ingrid; Hauser, Lorenz; Jorde, Per Erik; Knutsen, Halvor; Punt, André E; Rogers, Lauren A; Stenseth, Nils Chr

2018-05-08

Genetic data are commonly used to estimate connectivity between putative populations, but translating them to demographic dispersal rates is complicated. Theoretical equations that infer a migration rate based on the genetic estimator F ST , such as Wright's equation, F ST ≈ 1/(4 N e m + 1), make assumptions that do not apply to most real populations. How complexities inherent to real populations affect migration was exemplified by Atlantic cod in the North Sea and Skagerrak and was examined within an age-structured model that incorporated genetic markers. Migration was determined under various scenarios by varying the number of simulated migrants until the mean simulated level of genetic differentiation matched a fixed level of genetic differentiation equal to empirical estimates. Parameters that decreased the N e / N t ratio (where N e is the effective and N t is the total population size), such as high fishing mortality and high fishing gear selectivity, increased the number of migrants required to achieve empirical levels of genetic differentiation. Higher maturity-at-age and lower selectivity increased N e / N t and decreased migration when genetic differentiation was fixed. Changes in natural mortality, fishing gear selectivity, and maturity-at-age within expected limits had a moderate effect on migration when genetic differentiation was held constant. Changes in population size had the greatest effect on the number of migrants to achieve fixed levels of F ST , particularly when genetic differentiation was low, F ST ≈ 10 -3 Highly variable migration patterns, compared with constant migration, resulted in higher variance in genetic differentiation and higher extreme values. Results are compared with and provide insight into the use of theoretical equations to estimate migration among real populations. Copyright © 2018 the Author(s). Published by PNAS.

The ACTIVATE study: results from a group-randomized controlled trial comparing a traditional worksite health promotion program with an activated consumer program.

PubMed

Terry, Paul E; Fowles, Jinnet Briggs; Xi, Min; Harvey, Lisa

2011-01-01

PURPOSE. This study compares a traditional worksite-based health promotion program with an activated consumer program and a control program DESIGN. Group randomized controlled trial with 18-month intervention. SETTING. Two large Midwestern companies. SUBJECTS. Three hundred and twenty employees (51% response). INTERVENTION. The traditional health promotion intervention offered population-level campaigns on physical activity, nutrition, and stress management. The activated consumer intervention included population-level campaigns for evaluating health information, choosing a health benefits plan, and understanding the risks of not taking medications as prescribed. The personal development intervention (control group) offered information on hobbies. The interventions also offered individual-level coaching for high risk individuals in both active intervention groups. MEASURES. Health risk status, general health status, consumer activation, productivity, and the ability to evaluate health information. ANALYSIS. Multivariate analyses controlled for baseline differences among the study groups. RESULTS. At the population level, compared with baseline performance, the traditional health promotion intervention improved health risk status, consumer activation, and the ability to recognize reliable health websites. Compared with baseline performance, the activated consumer intervention improved consumer activation, productivity, and the ability to recognize reliable health websites. At the population level, however, only the activated consumer intervention improved any outcome more than the control group did; that outcome was consumer activation. At the individual level for high risk individuals, both traditional health coaching and activated consumer coaching positively affected health risk status and consumer activation. In addition, both coaching interventions improved participant ability to recognize a reliable health website. Consumer activation coaching also significantly improved self-reported productivity. CONCLUSION. An effective intervention can change employee health risk status and activation both at the population level and at the individual high risk level. However, program engagement at the population level was low, indicating that additional promotional strategies, such as greater use of incentives, need to be examined. Less intensive coaching can be as effective as more intensive, albeit both interventions produced modest behavior change and retention in the consumer activation arm was most difficult. Further research is needed concerning recruitment and retention methods that will enable populations to realize the full potential of activated consumerism.

Canada's population: growth and dualism.

PubMed

Beaujot, R P

1978-04-01

In Canada the current 1.3% population growth rate is causing some concern. Those concerned argue that such a rate of growth in combination with high levels of consumption could jeopardize the country's resource base and its comfortable style of living. Many Canadians are questioning high levels of immigration, for now that the fertility level is below replacement level, net immigration contributes substantially to population growth (over 1/3 in 1976). The growing proportion of non-Europeans among recent immigrants is causing resentment, and, in a tight job market, immigrants are regarded as threats to the World War 2 baby boom cohort who are now at working ages. The baby boom generation also puts stress on housing and health services, and it will increase the need for pension checks as it ages. Although French fertility is no longer high and immigration is no longer dominated by the British, the French group's 200-year struggle to preserve its identity continues on in the current effort of the Quebec government to enforce the use of French language by law within that province. Geography and climate dictate another demographic fact that divides the country and pervades its history. In addition to intense regionalism, uneven population distribution is responsible for 2 other concerns: the rapid growth of several already large cities and depopulation of many small communities. Focus in this discussion is on Canada's population growth in the past and as projected for the future, historical and current fertility, mortality and immigration trends, the search for a new immigration policy, the impact of the baby boom generation on the population's age structure and the problems this creates, and recent shifts in population distribution and in the country's ethnic and linguistic makeup. The population policy proposals evolved thus far involve to a great extent the use of immigration as a lever for achieving given population objectives.

Pleistocene refugia and polytopic replacement of diploids by tetraploids in the Patagonian and Subantarctic plant Hypochaeris incana (Asteraceae, Cichorieae).

PubMed

Tremetsberger, Karin; Urtubey, Estrella; Terrab, Anass; Baeza, Carlos M; Ortiz, María Angeles; Talavera, María; König, Christiane; Temsch, Eva M; Kohl, Gudrun; Talavera, Salvador; Stuessy, Tod F

2009-09-01

We report the phylogeographic pattern of the Patagonian and Subantarctic plant Hypochaeris incana endemic to southeastern South America. We applied amplified fragment length polymorphism (AFLP) and chloroplast DNA (cpDNA) analysis to 28 and 32 populations, respectively, throughout its distributional range and assessed ploidy levels using flow cytometry. While cpDNA data suggest repeated or simultaneous parallel colonization of Patagonia and Tierra del Fuego by several haplotypes and/or hybridization, AFLPs reveal three clusters corresponding to geographic regions. The central and northern Patagonian clusters (approximately 38-51 degrees S), which are closer to the outgroup, contain mainly tetraploid, isolated and highly differentiated populations with low genetic diversity. To the contrary, the southern Patagonian and Fuegian cluster (approximately 51-55 degrees S) contains mainly diploid populations with high genetic diversity and connected by high levels of gene flow. The data suggest that H. incana originated at the diploid level in central or northern Patagonia, from where it migrated south. All three areas, northern, central and southern, have similar levels of rare and private AFLP bands, suggesting that all three served as refugia for H. incana during glacial times. In southern Patagonia and Tierra del Fuego, the species seems to have expanded its populational system in postglacial times, when the climate became warmer and more humid. In central and northern Patagonia, the populations seem to have become restricted to favourable sites with increasing temperature and decreasing moisture and there was a parallel replacement of diploids by tetraploids in local populations.

The effects of country-level population policy for enhancing adaptation to climate change

NASA Astrophysics Data System (ADS)

Gunasekara, N. K.; Kazama, S.; Yamazaki, D.; Oki, T.

2013-11-01

The effectiveness of population policy in reducing the combined impacts of population change and climate change on water resources is explored. One no-policy scenario and two scenarios with population policy assumptions are employed in combination with water availability under the SRES scenarios A1b, B1 and A2 for the impact analysis. The population data used are from the World Bank. The river discharges per grid of horizontal resolution 0.5° are obtained from the Total Runoff Integrating Pathways (TRIP) of the University of Tokyo, Japan. Unlike the population scenarios utilized in the SRES emission scenarios and the newest representative concentration pathways, the scenarios employed in this research are based, even after 2050, on country-level rather than regional-level growth assumptions. Our analysis implies that the heterogeneous pattern of population changes across the world is the dominant driver of water stress, irrespective of future greenhouse gas emissions, with highest impacts occurring in the already water-stressed low latitudes. In 2100, Africa, Middle East and parts of Asia are under extreme water stress under all scenarios. The sensitivity analysis reveals that a small reduction in populations over the region could relieve a large number of people from high water stress, while a further increase in population from the assumed levels (SC1) might not increase the number of people under high water stress considerably. Most of the population increase towards 2100 occurs in the already water-stressed lower latitudes. Therefore, population reduction policies are recommended for this region as a method of adaptation to the future water stress conditions. Population reduction policies will facilitate more control over their future development pathways, even if these countries were not able to contribute significantly to greenhouse gas (GHG) emission cuts due to economic constraints. However, for the European region, the population living in water-stressed regions is almost 20 times lower than that in the lower latitudes. For countries with high population momentum, the population policy scenario with fertility-reduction assumptions gained a maximum of 6.1 times the water availability in Niger and 5.3 times that in Uganda compared with the no-policy scenario. Most of these countries are in sub-Saharan Africa. These countries represent 24.5% of the global population in the no-policy scenario, and the scenario with fertility-reduction assumptions reduces it to 8.7% by 2100. This scenario is also effective in reducing the area under extreme water stress in these countries. However, the policy scenario with assumptions of population stabilization at the replacement fertility rate increases the water stress in high-latitude countries. Nevertheless, the impact is low due to the high per capita water availability in the region. This research is expected to widen the understanding of the combined impacts of climate change in the future and of the strategies needed to enhance the space for adaptation.

A distinct bacterial dysbiosis associated skin inflammation in ovine footrot

NASA Astrophysics Data System (ADS)

Maboni, Grazieli; Blanchard, Adam; Frosth, Sara; Stewart, Ceri; Emes, Richard; Tötemeyer, Sabine

2017-03-01

Ovine footrot is a highly prevalent bacterial disease caused by Dichelobacter nodosus and characterised by the separation of the hoof horn from the underlying skin. The role of innate immune molecules and other bacterial communities in the development of footrot lesions remains unclear. This study shows a significant association between the high expression of IL1β and high D. nodosus load in footrot samples. Investigation of the microbial population identified distinct bacterial populations in the different disease stages and also depending on the level of inflammation. Treponema (34%), Mycoplasma (29%) and Porphyromonas (15%) were the most abundant genera associated with high levels of inflammation in footrot. In contrast, Acinetobacter (25%), Corynebacteria (17%) and Flavobacterium (17%) were the most abundant genera associated with high levels of inflammation in healthy feet. This demonstrates for the first time there is a distinct microbial community associated with footrot and high cytokine expression.

Unravelling the effects of gene flow and selection in highly connected populations of the silver-lip pearl oyster (Pinctada maxima).

PubMed

Nayfa, Maria G; Zenger, Kyall R

2016-08-01

Many marine organisms often display weak levels of population genetic structuring as a result of both environmental characteristics (e.g., ocean currents) and life history traits (e.g., widely dispersed planktonic larval stages) maintaining high levels of gene flow. This can lead to the assumption that these organisms can be managed as a single stock based on high levels of population connectivity. However, this neglects to account for other micro-evolutionary forces such as selection, which also shape these populations. This study utilizes 1130 genome-wide SNP loci to unravel the effects of gene flow and selection shaping three highly connected populations of the silver-lip pearl oyster (Pinctada maxima) in the ecologically and economically important Indo-Pacific region (Aru, Bali, and West Papua). Twenty-two loci under directional selection were identified amongst the populations, providing further supporting evidence of strong local adaptation (i.e., G×E effects) among populations in this region. Global Fst values for directional outliers (0.348) were up to eight times greater than for neutral markers (0.043). Pairwise Fst comparisons between Aru and Bali revealed the largest directional differences (0.488), while Bali and West Papua had the least (0.062). Unrooted neighbour-joining (NJ) distance trees and genetic diversity indices of directional outliers revealed that individuals from Bali and West Papua had reduced allelic variation (MAFavg=0.144, Ho=0.238 and MAFavg=0.232, Ho=0.369, respectively) compared to Aru (MAFavg=0.292, Ho=0.412). This indicates that directional selection is most likely acting upon genetic variation within the Bali and West Papua populations. NJ distance trees, discriminant analysis of principal components, and Fst analyses of directional outliers revealed two divergent groups ("Bali/West Papua"; "Aru") that had previously gone unrecognized. This study not only illustrates that relatively strong local adaptive forces are occurring despite high gene flow, but identifies the populations that are most likely experiencing selection. Additionally, this study highlights the need to understand all micro-evolutionary forces acting on populations when resolving stock structure. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Inter-Simple Sequence Repeat Data Reveals High Genetic Diversity in Wild Populations of the Narrowly Distributed Endemic Lilium regale in the Minjiang River Valley of China

PubMed Central

Wu, Zhu-hua; Shi, Jisen; Xi, Meng-li; Jiang, Fu-xing; Deng, Ming-wen; Dayanandan, Selvadurai

2015-01-01

Lilium regale E.H. Wilson is endemic to a narrow geographic area in the Minjiang River valley in southwestern China, and is considered an important germplasm for breeding commercially valuable lily varieties, due to its vigorous growth, resistance to diseases and tolerance for low moisture. We analyzed the genetic diversity of eight populations of L. regale sampled across the entire natural distribution range of the species using Inter-Simple Sequence Repeat markers. The genetic diversity (expected heterozygosity= 0.3356) was higher than those reported for other narrowly distributed endemic plants. The levels of inbreeding (F st = 0.1897) were low, and most of the genetic variability was found to be within (80.91%) than amongpopulations (19.09%). An indirect estimate of historical levels of gene flow (N m =1.0678) indicated high levels of gene flow among populations. The eight analyzed populations clustered into three genetically distinct groups. Based on these results, we recommend conservation of large populations representing these three genetically distinct groups. PMID:25799495

Lethal mutagenesis: targeting the mutator phenotype in cancer.

PubMed

Fox, Edward J; Loeb, Lawrence A

2010-10-01

The evolution of cancer and RNA viruses share many similarities. Both exploit high levels of genotypic diversity to enable extensive phenotypic plasticity and thereby facilitate rapid adaptation. In order to accumulate large numbers of mutations, we have proposed that cancers express a mutator phenotype. Similar to cancer cells, many viral populations, by replicating their genomes with low fidelity, carry a substantial mutational load. As high levels of mutation are potentially deleterious, the viral mutation frequency is thresholded at a level below which viral populations equilibrate in a traditional mutation-selection balance, and above which the population is no longer viable, i.e., the population undergoes an error catastrophe. Because their mutation frequencies are fine-tuned just below this error threshold, viral populations are susceptible to further increases in mutational load and, recently this phenomenon has been exploited therapeutically by a concept that has been termed lethal mutagenesis. Here we review the application of lethal mutagenesis to the treatment of HIV and discuss how lethal mutagenesis may represent a novel therapeutic approach for the treatment of solid cancers. Copyright © 2010 Elsevier Ltd. All rights reserved.

Population-Level Exposure to Particulate Air Pollution during Active Travel: Planning for Low-Exposure, Health-Promoting Cities.

PubMed

Hankey, Steve; Lindsey, Greg; Marshall, Julian D

2017-04-01

Providing infrastructure and land uses to encourage active travel (i.e., bicycling and walking) are promising strategies for designing health-promoting cities. Population-level exposure to air pollution during active travel is understudied. Our goals were a ) to investigate population-level patterns in exposure during active travel, based on spatial estimates of bicycle traffic, pedestrian traffic, and particulate concentrations; and b ) to assess how those exposure patterns are associated with the built environment. We employed facility-demand models (active travel) and land use regression models (particulate concentrations) to estimate block-level ( n = 13,604) exposure during rush-hour (1600-1800 hours) in Minneapolis, Minnesota. We used the model-derived estimates to identify land use patterns and characteristics of the street network that are health promoting. We also assessed how exposure is correlated with indicators of health disparities (e.g., household income, proportion of nonwhite residents). Our work uses population-level rates of active travel (i.e., traffic flows) rather than the probability of walking or biking (i.e., "walkability" or "bikeability") to assess exposure. Active travel often occurs on high-traffic streets or near activity centers where particulate concentrations are highest (i.e., 20-42% of active travel occurs on blocks with high population-level exposure). Only 2-3% of blocks (3-8% of total active travel) are "sweet spots" (i.e., high active travel, low particulate concentrations); sweet spots are located a ) near but slightly removed from the city-center or b ) on off-street trails. We identified 1,721 blocks (~ 20% of local roads) where shifting active travel from high-traffic roads to adjacent low-traffic roads would reduce exposure by ~ 15%. Active travel is correlated with population density, land use mix, open space, and retail area; particulate concentrations were mostly unchanged with land use. Public health officials and urban planners may use our findings to promote healthy transportation choices. When designing health-promoting cities, benefits (physical activity) as well as hazards (air pollution) should be evaluated.

Prevalence and treatment of atherogenic dyslipidemia in the primary prevention of cardiovascular disease in Europe: EURIKA, a cross-sectional observational study.

PubMed

Halcox, Julian P; Banegas, José R; Roy, Carine; Dallongeville, Jean; De Backer, Guy; Guallar, Eliseo; Perk, Joep; Hajage, David; Henriksson, Karin M; Borghi, Claudio

2017-06-17

Atherogenic dyslipidemia is associated with poor cardiovascular outcomes, yet markers of this condition are often ignored in clinical practice. Here, we address a clear evidence gap by assessing the prevalence and treatment of two markers of atherogenic dyslipidemia: elevated triglyceride levels and low levels of high-density lipoprotein cholesterol. This cross-sectional observational study assessed the prevalence of two atherogenic dyslipidemia markers, high triglyceride levels and low high-density lipoprotein cholesterol levels, in the study population from the European Study on Cardiovascular Risk Prevention and Management in Usual Daily Practice (EURIKA; N = 7641; of whom 51.6% were female and 95.6% were White/Caucasian). The EURIKA population included European patients, aged at least 50 years with at least one cardiovascular risk factor but no history of cardiovascular disease. Over 20% of patients from the EURIKA population have either triglyceride or high-density lipoprotein cholesterol levels characteristic of atherogenic dyslipidemia. Furthermore, the proportions of patients with one of these markers were higher in subpopulations with type 2 diabetes mellitus or those already calculated to be at high risk of cardiovascular disease. Approximately 55% of the EURIKA population who have markers of atherogenic dyslipidemia are not receiving lipid-lowering therapy. A considerable proportion of patients with at least one major cardiovascular risk factor in the primary cardiovascular disease prevention setting have markers of atherogenic dyslipidemia. The majority of these patients are not receiving optimal treatment, as specified in international guidelines, and thus their risk of developing cardiovascular disease is possibly underestimated. The present study is registered with ClinicalTrials.gov (ID: NCT00882336).

Burnout in the working population: relations to psychosocial work factors.

PubMed

Lindblom, Karin M; Linton, Steven J; Fedeli, Cecilia; Bryngelsson, Ing-Liss

2006-01-01

This study investigated levels of burnout in the general population irrespective of occupation and relations between burnout and psychosocial work factors. A cross-sectional survey featuring sleep problems, psychological distress, burnout (Maslach Burnout Inventory-General Survey), and psychosocial factors at work, was mailed to a random sample of 3,000 participants, aged 20-60. Response rate was 61%. A high level (18%), a low level (19%), and an intermediate group (63%) for burnout were constructed. The high level group was associated with those who were > 50 years old, women, those experiencing psychological distress, and those with a poor psychosocial work climate. The analyses on variables significant in previous analyses showed that the high level group was strongly related to high demands, low control, lack of social support, and disagreeing about values at the workplace even when accounting for age, gender, and psychological distress. We conclude that psychosocial work factors are important in association to burnout regardless of occupation.

Role of egg predation by haddock in the decline of an Atlantic herring population

PubMed Central

Richardson, David E.; Hare, Jonathan A.; Fogarty, Michael J.; Link, Jason S.

2011-01-01

Theoretical studies suggest that the abrupt and substantial changes in the productivity of some fisheries species may be explained by predation-driven alternate stable states in their population levels. With this hypothesis, an increase in fishing or a natural perturbation can drive a population from an upper to a lower stable-equilibrium population level. After fishing is reduced or the perturbation ended, this low population level can persist due to the regulatory effect of the predator. Although established in theoretical studies, there is limited empirical support for predation-driven alternate stable states in exploited marine fish populations. We present evidence that egg predation by haddock (Melanogrammus aeglefinus) can cause alternate stable population levels in Georges Bank Atlantic herring (Clupea harengus). Egg predation by haddock explains a substantial decoupling of herring spawning stock biomass (an index of egg production) from observed larval herring abundance (an index of egg hatching). Estimated egg survival rates ranged from <2–70% from 1971 to 2005. A population model incorporating egg predation and herring fishing explains the major population trends of Georges Bank herring over four decades and predicts that, when the haddock population is high, seemingly conservative levels of fishing can still precipitate a severe decline in the herring population. These findings illustrate how efforts to rebuild fisheries can be undermined by not incorporating ecological interactions into fisheries models and management plans. PMID:21825166

Predicting the sensitivity of populations from individual exposure to chemicals: the role of ecological interactions.

PubMed

Gabsi, Faten; Schäffer, Andreas; Preuss, Thomas G

2014-07-01

Population responses to chemical stress exposure are influenced by nonchemical, environmental processes such as species interactions. A realistic quantification of chemical toxicity to populations calls for the use of methodologies that integrate these multiple stress effects. The authors used an individual-based model for Daphnia magna as a virtual laboratory to determine the influence of ecological interactions on population sensitivity to chemicals with different modes of action on individuals. In the model, hypothetical chemical toxicity targeted different vital individual-level processes: reproduction, survival, feeding rate, or somatic growth rate. As for species interactions, predatory and competition effects on daphnid populations were implemented following a worst-case approach. The population abundance was simulated at different food levels and exposure scenarios, assuming exposure to chemical stress solely or in combination with either competition or predation. The chemical always targeted one vital endpoint. Equal toxicity-inhibition levels differently affected the population abundance with and without species interactions. In addition, population responses to chemicals were highly sensitive to the environmental stressor (predator or competitor) and to the food level. Results show that population resilience cannot be attributed to chemical stress only. Accounting for the relevant ecological interactions would reduce uncertainties when extrapolating effects of chemicals from individuals to the population level. Validated population models should be used for a more realistic risk assessment of chemicals. © 2014 SETAC.

EVALUATION, ASSESSMENT, AND DETERMINATION OF RISK TO HIGH TROPHIC LEVEL PISCIVORES IN THE MID-ATLANTIC: A SPATIAL, BIOLOGICAL, AND COMPARATIVE CASE STUDY OF MERCURY IN VIRGINIA AND NEW ENGLAND BALD EAGLE (HALIAEETUS LEUCOCEPHALUS) POPULATIONS

EPA Science Inventory

I predict that some portion of the Virginia bald eagle population will exhibit levels at or above those considered detrimental to productivity and reproductive success. The analysis of independent variables and their relationship to elevated blood mercury levels will help t...

Hepatitis A outbreak in HIV-infected MSM and in PrEP-using MSM despite a high level of immunity, Lyon, France, January to June 2017.

PubMed

Charre, Caroline; Ramière, Christophe; Roque-Afonso, Anne-Marie; Chidiac, Christian; Zoulim, Fabien; Godinot, Matthieu; Koffi, Joseph; Scholtès, Caroline; Livrozet, Jean-Michel; Hav Lyon Study Group; Cotte, Laurent

2017-11-01

Since 2016, an increase in the number of hepatitis A cases affecting mainly men who have sex with men (MSM) has been reported in low endemic countries in Europe. We calculated the attack rate in Lyon, France, in populations considered at high-risk: HIV-infected MSM and HIV-negative MSM receiving HIV pre-exposure prophylaxis (PrEP). In these populations, high level of immunity did not prevent the outbreak, indicating that vaccination should be reinforced, particularly in younger individuals.

Hepatitis A outbreak in HIV-infected MSM and in PrEP-using MSM despite a high level of immunity, Lyon, France, January to June 2017

PubMed Central

Charre, Caroline; Ramière, Christophe; Roque-Afonso, Anne-Marie; Chidiac, Christian; Zoulim, Fabien; Godinot, Matthieu; Koffi, Joseph; Scholtès, Caroline; Livrozet, Jean-Michel; Cotte, Laurent

2017-01-01

Since 2016, an increase in the number of hepatitis A cases affecting mainly men who have sex with men (MSM) has been reported in low endemic countries in Europe. We calculated the attack rate in Lyon, France, in populations considered at high-risk: HIV-infected MSM and HIV-negative MSM receiving HIV pre-exposure prophylaxis (PrEP). In these populations, high level of immunity did not prevent the outbreak, indicating that vaccination should be reinforced, particularly in younger individuals. PMID:29208161

Combined effects between temporal heterogeneity of water supply, nutrient level, and population density on biomass of four broadly distributed herbaceous species.

PubMed

Hagiwara, Yousuke; Kachi, Naoki; Suzuki, Jun-Ichirou

2012-01-01

Temporal heterogeneity of water supply affects grassland community productivity and it can interact with nutrient level and intraspecific competition. To understand community responses, the responses of individual species to water heterogeneity must be evaluated while considering the interactions of this heterogeneity with nutrient levels and population density. We compared responses of four herbaceous species grown in monocultures to various combinations of water heterogeneity, nutrient level, and population density: two grasses (Cynodon dactylon and Lolium perenne), a forb (Artemisia princeps), and a legume (Trifolium repens). Treatment effects on shoot and root biomass were analyzed. In all four species, shoot biomass was larger under homogeneous than under heterogeneous water supply. Shoot responses of L. perenne tended to be greater at high nutrient levels. Although root biomass was also larger under homogeneous water supply, effects of water heterogeneity on root biomass were not significant in the grasses. Trifolium repens showed marked root responses, particularly at high population density. Although greater shoot and root growth under homogeneous water supply appears to be a general trend among herbaceous species, our results suggested differences among species could be found in the degree of response to water heterogeneity and its interactions with nutrient level and intraspecific competition.

Assessment of diversity among populations of Rauvolfia serpentina Benth. Ex. Kurtz. from Southern Western Ghats of India, based on chemical profiling, horticultural traits and RAPD analysis.

PubMed

Nair, Vadakkemuriyil Divya; Raj, Rajan Pillai Dinesh; Panneerselvam, Rajaram; Gopi, Ragupathi

2014-01-01

Genetic, morphological and chemical variations of ten natural populations of Rauvolfia serpentina Benth. Ex. Kurtz. from Southern Western Ghats of India were assessed using RAPD markers reserpine content and morphological traits. An estimate of genetic diversity and differentiation between genotypes of breeding germplasm is of key importance for its improvement. Populations were collected from different geographical regions. Data obtained through three different methods were compared and the correlation among them was estimated. Statistical analysis showed significant differences for all horticultural characteristics among the accessions suggesting that selection for relevant characteristics could be possible. Variation in the content of Reserpine ranges from 0.192 g/100 g (population from Tusharagiri) to 1.312 g/100 g (population from Aryankavu). A high diversity within population and high genetic differentiation among them based on RAPDs were revealed caused both by habitat fragmentation of the low size of most populations and the low level of gene flow among them. The UPGMA dendrogram and PCA analysis based on reserpine content yielded higher separation among populations indicated specific adaptation of populations into clusters each of them including populations closed to their geographical origin. Genetic, chemical and morphological data were correlated based on Mantel test. Given the high differentiation among populations conservation strategies should take into account genetic diversity and chemical variation levels in relation to bioclimatic and geographic location of populations. Our results also indicate that RAPD approach along with horticultural analysis seemed to be best suited for assessing with high accuracy the genetic relationships among distinct R. serpentina accessions. © 2013.

Venezuela.

PubMed

1982-02-01

This discussion of Venezuela reviews the following: the history of the country's demographic situation; the government's overall approach to population problems; statistical systems and development planning; institutional arrangements for the integration of population within development planning; the government's view of the importance of population policy in realizing development objectives; population size, growth, and natural increase; morbidity and mortality; fertility; international migration; and spatial distribution. Over the 1920-1961 period Venezuela's level of fertility was high and continued to rise gradually. The crude birth rate was around 40.0/1000 population in 1920, 44.0/1000 in 1950, and 45.0/1000 in 1961, and thereafter began to decline, dropping to a level of 38.4/1000 by 1971. During the same period, mortality underwent a steady decline, with the crude death rate falling from 30.0/1000 population in 1920 to 13.7 in 1950, 7.4 in 1961, and to 6.6 by 1971. Venezuela's government has no policy of intervention to modify fertility or population growth but has relied primarily on the benefits of rapid economic growth to achieve a rate of demographic growth that is compatible with its development objectives. Since 1920, 7 modern censuses have been conducted. The most recent census was in 1971. The registration data are classified as incomplete. Multiround sample household surveys were conducted in 1976-1977 and 1978. The government has not established a special unit for population policies. It assigned this function to the Central Planning Agency in 1975. The government has not announced a comprehensive population policy, but it has been moving in the direction of formulating more comprehensive policies in 2 areas of concern--international migration and spatial distribution. The government considers the current rate of population growth to be satisfactory despite the fact that it is rather high by Latin American standards. The government also considers levels and trends of mortality to be acceptable, given current economic and social circumstances. The government currently considers levels and trends of immigration to be significant and unsatisfactory because they are too high. The country is now more than 75% urban. The government considers the distribution of population within the national territory to be inappropriate and to require substantial modification.

Four-Photon Stark Induced Ladder Climbing Prepares Large Ensemble of H2in Selected High Lying Vibrational Levels

NASA Astrophysics Data System (ADS)

Mukherjee, Nandini; Perreault, William; Zare, Richard

2017-04-01

To selectively prepare highly vibrationally excited quantum states of molecules like H2, we present a novel multi-photon ladder-climbing technique where the successive rungs of the ladder are connected by Stark-induced adiabatic Raman passage (SARP). Previously, we have demonstrated that SARP achieves complete population transfer from the v = 0 to the v = 1 and v = 4 levels of H2. We show here that SARP can be generalized into a continuously coupled, multiphoton adiabatic passage which uses one or more intermediate states having strong Raman coupling to access highly vibrationally excited states weakly coupled to the ground state. As an example, we consider the case of four-photon coherent excitation to high vibrational levels of H2 via an intermediate level coupled to both the initial and target levels by two-photon SARP. Using a sequence of commercially available single mode, nanosecond lasers, a pump pulse partially overlapping with two Stokes pulses, we show that the complete population of v = 0 can be selectively transferred to the most weakly coupled v = 6 and v = 9 vibrational levels of H2, without leaving any population stranded in the intermediate level. The present method provides a practical way of generating an entangled pair of fragments without resorting to an ultracold system. This work has been supported by US Army Research Office under ARO Grant No. W911NF-16-1-1061.

Cross-generational environmental effects and the evolution of offspring size in the Trinidadian guppy Poecilia reticulata.

PubMed

Bashey, Farrah

2006-02-01

The existence of adaptive phenotypic plasticity demands that we study the evolution of reaction norms, rather than just the evolution of fixed traits. This approach requires the examination of functional relationships among traits not only in a single environment but across environments and between traits and plasticity itself. In this study, I examined the interplay of plasticity and local adaptation of offspring size in the Trinidadian guppy, Poecilia reticulata. Guppies respond to food restriction by growing and reproducing less but also by producing larger offspring. This plastic difference in offspring size is of the same order of magnitude as evolved genetic differences among populations. Larger offspring sizes are thought to have evolved as an adaptation to the competitive environment faced by newborn guppies in some environments. If plastic responses to maternal food limitation can achieve the same fitness benefit, then why has guppy offspring size evolved at all? To explore this question, I examined the plastic response to food level of females from two natural populations that experience different selective environments. My goals were to examine whether the plastic responses to food level varied between populations, test the consequences of maternal manipulation of offspring size for offspring fitness, and assess whether costs of plasticity exist that could account for the evolution of mean offspring size across populations. In each population, full-sib sisters were exposed to either a low- or high-food treatment. Females from both populations produced larger, leaner offspring in response to food limitation. However, the population that was thought to have a history of selection for larger offspring was less plastic in its investment per offspring in response to maternal mass, maternal food level, and fecundity than the population under selection for small offspring size. To test the consequences of maternal manipulation of offspring size for offspring fitness, I raised the offspring of low- and high-food mothers in either low- or high-food environments. No maternal effects were detected at high food levels, supporting the prediction that mothers should increase fecundity rather than offspring size in noncompetitive environments. For offspring raised under low food levels, maternal effects on juvenile size and male size at maturity varied significantly between populations, reflecting their initial differences in maternal manipulation of offspring size; nevertheless, in both populations, increased investment per offspring increased offspring fitness. Several correlates of plasticity in investment per offspring that could affect the evolution of offspring size in guppies were identified. Under low-food conditions, mothers from more plastic families invested more in future reproduction and less in their own soma. Similarly, offspring from more plastic families were smaller as juveniles and female offspring reproduced earlier. These correlations suggest that a fixed, high level of investment per offspring might be favored over a plastic response in a chronically low-resource environment or in an environment that selects for lower reproductive effort.

Spatial distribution of mumps in South Korea, 2001-2015: identifying clusters and population risk factors.

PubMed

Choe, Y-J; Min, K; Cho, S-I

2017-07-01

In South Korea, the resurgence of mumps was noted primarily among school-aged children and adolescents since 2000. We analyzed spatial patterns in mumps incidence to give an indication to the geographical risk. We used National Notifiable Disease Surveillance System data from 2001 to 2015, classifying into three periods according to the level of endemicity. A geographic-weighted regression analysis was performed to find demographic predictors of mumps incidence according to district level. We assessed the association between the total population size, population density, percentage of children (age 0-19 years), timely vaccination rate of measles-mumps-rubella vaccines and the higher incidence rate of mumps. During low endemic periods, there were sporadic regional distributions of outbreak in the central and northern part of the country. During intermediate endemic periods, the increase of incidence was noted across the country. During high endemic period, a nationwide high incidence of mumps was noted especially concentrated in southwestern regions. A clear pattern for the mumps cluster shown through global spatial autocorrelation analysis from 2004 to 2015. The 'non-timely vaccination coverage' (P = 0·002), and 'proportion of children population' (P < 0·001) were the predictors for high mumps incidence in district levels. Our study indicates that the rate of mumps incidence according to geographic regions vary by population proportion and neighboring regions, and timeliness of vaccination, suggesting the importance of community-level surveillance and improving of timely vaccination.

Phenotypic and Genetic Divergence among Poison Frog Populations in a Mimetic Radiation

PubMed Central

Twomey, Evan; Yeager, Justin; Brown, Jason Lee; Morales, Victor; Cummings, Molly; Summers, Kyle

2013-01-01

The evolution of Müllerian mimicry is, paradoxically, associated with high levels of diversity in color and pattern. In a mimetic radiation, different populations of a species evolve to resemble different models, which can lead to speciation. Yet there are circumstances under which initial selection for divergence under mimicry may be reversed. Here we provide evidence for the evolution of extensive phenotypic divergence in a mimetic radiation in Ranitomeya imitator, the mimic poison frog, in Peru. Analyses of color hue (spectral reflectance) and pattern reveal substantial divergence between morphs. However, we also report that there is a “transition-zone” with mixed phenotypes. Analyses of genetic structure using microsatellite variation reveals some differentiation between populations, but this does not strictly correspond to color pattern divergence. Analyses of gene flow between populations suggest that, while historical levels of gene flow were low, recent levels are high in some cases, including substantial gene flow between some color pattern morphs. We discuss possible explanations for these observations. PMID:23405150

Risk Factors for High Myopia in Koreans: The Korea National Health and Nutrition Examination Survey.

PubMed

Hwang, Ho Sik; Chun, Min Young; Kim, Jin Sun; Oh, Bumjo; Yoo, Sang Ho; Cho, Bum-Joo

2018-05-02

To investigate risk factors for high myopia in the general Korean population. In this nationwide population study, the dataset of the Korea National Health and Nutrition Examination Survey 2008-2012 was analyzed. The study cohort included 11 703 participants, aged 25-49 years, who underwent neither refractive nor cataract surgery. The association between demographic, socioeconomic, behavioral, and systemic variables and high myopia was investigated. The mean participant age was 37.9 ± 6.8 years, and the prevalence of high myopia ≤-6.0D was 7.0 ± 0.3% in the study population. The right eyes (-1.76 ± 0.03 D) were more myopic than the left eyes (-1.70 ± 0.03 D; P < 0.001). In multivariate logistic regression analysis, high myopia was associated with age (odds ratio [OR], 0.97 per 1 year-increase) and female sex (OR, 1.24). Other identified risk factors included education level ≥ university graduation (OR, 1.91), the presence of hypertension (OR, 1.69), and serum glucose level (OR, 1.01 per 1 mg/dL). Sunlight exposure of ≥5 h/day (OR, 0.67) and serum 25-hydroxyvitamin D level (OR, 0.97 per 1 ng/mL) showed protective effect against high myopia. High myopia is associated with younger age, female sex, high education level, longer sunlight exposure, and some other systemic conditions.

Plasma YKL-40 in Inuit and Danes.

PubMed

Nøjgaard, Camilla; Johansen, Julia S; Bjerregaard, Peter; Bojesen, Stig E; Becker, Ulrik

2015-01-01

The aim of the present study was to investigate whether there are differences in plasma levels of YKL-40 between Inuit in Greenland and in Denmark and in Danes, as well as to study the relationship between alcohol intake, plasma YKL-40 and other factors in Inuit. Plasma YKL-40 levels were measured on 1645 people from The Greenland Population Study (a cross-sectional population study of Inuit from Denmark and West Greenland) and were compared with the plasma YKL-40 levels of 8899 people from The Copenhagen City Heart Study (a population-based, prospective study of the Danish general population). The plasma concentrations of YKL-40 were significantly (P = 0.001) lower in Inuit living in Greenland (median 46 µg/l, range 10-2164, n = 1164) compared with the plasma YKL-40 levels of Inuit living in Denmark (median 63 µg/l, range 20-2827, n = 481) and of Danes living in Denmark (median 55 µg/l, range 10-2909, n = 8899). In Inuit, increased alcohol intake was significantly associated with increased plasma YKL-40 levels (P < 0.001), and high plasma YKL-40 levels were associated with high values of alkaline phosphatase and low values of albumin. Smoking, gender and bilirubin were not associated with the plasma YKL-40 level. High levels of YKL-40 and alcohol were associated with where people lived. The plasma concentrations of YKL-40 are significantly lower in Inuit living in Greenland than Inuit and Danes living in Denmark. A number of factors, including different alcohol intake patterns, nutrition and genes may play a role in these findings. © The Author 2014. Medical Council on Alcohol and Oxford University Press. All rights reserved.

Persistent organic pollutants in maternal blood plasma and breast milk from Russian arctic populations.

PubMed

Klopov, V; Odland, J O; Burkow, I C

1998-10-01

Under the auspices of Arctic Monitoring and Assessment Programme (AMAP), a Russian-Norwegian co-operation project was established to assess the exposure of delivering women to persistent organic pollutants (POPs) in Arctic areas of Russia. In the period 1993-95 blood and breast milk samples were collected from 94 delivering women in Yamal and Tajmyr Autonomous Regions of Siberia. Concentrations of chlorinated pesticides and polychlorinated biphenyls (PCBs) were determined by high resolution gas chromatography with electron capture detection. The POP levels in maternal plasma among the non-indigenous women were higher than the native population, especially in total PCB, HCHs (hexachlorocyclohexanes) and the DDT-group. The dietary questionnaires showed that the non-indigenous populations consumed considerably less local food items like reindeer meat and fresh water fish. There was no correlation between local food consumption and elevated levels of pollutants. Even if the indigenous groups had lower concentrations of the most important pollutants than the non-indigenous population, they were still higher than the levels measured in the Scandinavian countries of the AMAP-study and up to levels of medical concern. The most important sources of organic pollutants for the Russian Arctic populations of Yamal and Tajmyr seems to be imported food from other areas of Russia and local use of pesticides. It must be a high priority concern to further elucidate these trends and initiate prophylactic measures for the exposed population groups.

Social cohesion among kin, gene flow without dispersal and the evolution of population genetic structure in the killer whale (Orcinus orca).

PubMed

Pilot, M; Dahlheim, M E; Hoelzel, A R

2010-01-01

In social species, breeding system and gregarious behavior are key factors influencing the evolution of large-scale population genetic structure. The killer whale is a highly social apex predator showing genetic differentiation in sympatry between populations of foraging specialists (ecotypes), and low levels of genetic diversity overall. Our comparative assessments of kinship, parentage and dispersal reveal high levels of kinship within local populations and ongoing male-mediated gene flow among them, including among ecotypes that are maximally divergent within the mtDNA phylogeny. Dispersal from natal populations was rare, implying that gene flow occurs without dispersal, as a result of reproduction during temporary interactions. Discordance between nuclear and mitochondrial phylogenies was consistent with earlier studies suggesting a stochastic basis for the magnitude of mtDNA differentiation between matrilines. Taken together our results show how the killer whale breeding system, coupled with social, dispersal and foraging behaviour, contributes to the evolution of population genetic structure.

Investigation of glyphosate resistance levels and target-site based resistance (TSR) mechanisms in Conyza canadensis (L.) from apple orchards around areas of Bohai seas and Loess Plateau in China.

PubMed

Mei, Yu; Xu, Yufang; Wang, Shipeng; Qiu, Lihong; Zheng, Mingqi

2018-04-01

The resistance levels to glyphosate and target-site based resistance mechanisms in susceptible (S) and resistant (R) Conyza canadensis (L.) populations, which were collected from apple orchards around areas of Bohai seas and Loess Plateau in China, were investigated. Among forty C. canadensis populations, eighteen populations (45%) were still susceptible; fourteen populations (35%) evolved low resistance levels resistance to glyphosate with resistance index (RI) of 2.02 to 3.90. In contrast, eight populations (20%) evolved medium resistance levels with RI of 4.35 to 8.38. The shikimic acid concentrations in R populations were highly negative relative with the glyphosate resistance levels in C. canadensis, the Pearson correlation coefficient was -0.82 treated by glyphosate at 1.8mg/L. Three 5-enoylpyruvylshikimate 3'-phosphate synthase genes (EPSPS1, EPSPS2 and EPSPS3) were cloned in all S and glyphosate-resistant C. canadensis populations. No amino acid substitution was identified at site of 102 and 106 in three EPSPS genes, which were reported to confer glyphosate resistance in other weed species. The relative expression level of EPSPS mRNA in R populations (SD07, LN05, SHX06 and SD09) was 4.5 to 13.2 times higher than in S biotype. The Pearson correlation coefficient between EPSPS expression levels and RI was 0.79, which indicated the over expression of EPSPS mRNA may cause these R populations evolve higher resistance level to glyphosate. Copyright © 2018 Elsevier Inc. All rights reserved.

Relationships between spur- and orchard-level fruit bearing in almond (Prunus dulcis).

PubMed

Tombesi, Sergio; Lampinen, Bruce D; Metcalf, Samuel; DeJong, Theodore M

2011-12-01

Almond is often considered to be a moderately alternate-bearing species but historical yield data typically do not exhibit clear patterns of alternate bearing at the orchard level, while research has indicated that spurs (the main fruit bearing unit in almond trees) rarely produce fruit in two subsequent years. The objective of the present work was to analyze the bearing behavior of almond trees at both the orchard level and the individual spur level over multiple years to explain this apparent paradox. The 10-year yield patterns of three almond cultivars grown at three different sites within California were analyzed for tendencies of alternate bearing at the orchard level. At the individual spur level, data on spur viability, and number of flowers and fruits per spur were collected on 2400 individually tagged spurs that were observed over 6 years to characterize bearing at that level. At the orchard level one cultivar (Nonpareil) did exhibit a tendency for alternate bearing at one site (Kern) but other cultivars and sites did not. The orchard and the individual trees in which the spur population study was conducted showed tendencies for alternate bearing but the spur population did not. Only a relatively small percentage of the total tagged spur population bore fruit in any given year and therefore while individual fruiting spurs exhibited a high level of non-bearing after fruiting the previous year the spurs that did produce fruit in any year generally did not constitute enough of the total spur population to exhibit alternate bearing at the whole population level. Our results suggest that annual bearing fluctuations in almond are probably mainly due to year-to-year variations of parameters affecting fruit set and that high rates of fruit set in a given year may involve a larger-than-normal percentage of a spur population in fruit bearing. This would limit the size of the spur population available for flowering in the subsequent year and could cause alternate year bearing. However, from historical records, this would appear to be the exception rather than a normal circumstance. Therefore, almond should not be considered to be a strictly alternate-bearing species.

Population-level analysis and validation of an individual-based cutthroat trout model

Treesearch

Steven F. Railsback; Bret C. Harvey; Roland H. Lamberson; Derek E. Lee; Claasen Nathan J.; Shuzo Yoshihara

2002-01-01

Abstract - An individual-based model of stream trout is analyzed by testing its ability to reproduce patterns of population-level behavior observed in real trout: (1) "self-thinning," a negative power relation between weight and abundance; (2) a "critical period" of density-dependent mortality in young-of-the-year; (3) high and age-speci...

78 FR 49831 - Endangered and Threatened Wildlife and Plants; Proposed Designation of Critical Habitat for...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-15

... Service (NPS) for the Florida leafwing and the pine rockland ecosystem, in general. Sea Level Rise... habitat. In the best case scenario, which assumes low sea level rise, high financial resources, proactive... human population. In the worst case scenario, which assumes high sea level rise, low financial resources...

Gender differences in metabolic syndrome components among the Korean 66-year-old population with metabolic syndrome.

PubMed

Lee, Sangjin; Ko, Young; Kwak, Chanyeong; Yim, Eun-Shil

2016-01-23

Gender is thought to be an important factor in metabolic syndrome and its outcomes. Despite a number of studies that have demonstrated differences in metabolism and its components that are dependent on gender, limited information about gender differences on the characteristics of metabolic syndrome and its components is available regarding the Korean old adult population. This study aimed to identify gender differences in characteristics of the metabolic syndrome and other risk factors for cardiovascular disease. Secondary analysis of data from a nationwide cross-sectional survey for health examination at the time of transitioning from midlife to old age was performed. Multiple logistic regression models were used to estimate adjusted odds ratios and 95% confidence intervals for gender differences among the Korean 66-year-old population with metabolic syndrome. Gender differences in metabolic syndrome components that contributed to the diagnosis of metabolic syndrome were identified. In males, the most common component was high blood sugar levels (87.5%), followed by elevated triglyceride levels (83.5%) and high blood pressure (83.1%). In females, the most commonly identified component was elevated triglyceride levels (79.0%), followed by high blood sugar levels (78.6%) and high blood pressure (78.5%). Gender differences for other risk factors for cardiovascular disease, including family history, health habits, and body mass index were observed. Gender-specific public health policies and management strategies to prevent cardiovascular disease among the older adult population should be developed for Koreans undergoing the physiological transition to old age.

Mountain pine beetle host selection behavior confirms high resistance in Great Basin bristlecone pine

Treesearch

Erika L. Eidson; Karen E. Mock; Barbara J. Bentz

2017-01-01

Over the last two decades, mountain pine beetle (Dendroctonus ponderosae) populations reached epidemic levels across much of western North America, including high elevations where cool temperatures previously limited mountain pine beetle persistence. Many high-elevation pine species are susceptible hosts and experienced high levels of mortality in recent outbreaks, but...

Canadian population trends in leisure-time physical activity levels, 1981-1998.

PubMed

Bruce, Marny J; Katzmarzyk, Peter T

2002-12-01

Age, sex, geographic and temporal trends in leisure-time physical activity levels were examined using data from five national surveys conducted between 1981 and 1998. Physical activity energy expenditure (AEE) was higher among men compared to women, and in younger versus older adults. AEE increased from Eastern to Western Canada, with a significant temporal trend of increasing AEE. The prevalence of physical inactivity (expending <12.6 kJ x kg(-1) x day(-1) has decreased; however, it remains high (women: 77%; men: 74%). The high prevalence of physical inactivity emphasizes the importance of population-level physical activity surveillance and interventions.

The Effect of Experimental Geometry and Initial Conditions on the Shape of Coherent Population Trapping Resonances on the Fine Structure Levels of Thallium Atoms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karagodova, T.Ya.

2005-06-15

Specific features of the coherent population trapping effect are considered in the generalized {lambda} system whose lower levels are the magnetic sublevels of the fine structure levels of the thallium atom. Numerical experiments were performed aimed at examination of the coherent population trapping for the case of nontrivial, but feasible, initial populations of the upper metastable fine structure level. Such populations may be obtained, for example, due to the photodissociation of TlBr molecules. The possibility of reducing the number of resonances of the coherent population trapping in a multilevel system, which may be useful for high-resolution spectroscopy, is demonstrated. Itmore » is shown that the magnitude and shape of the resonances can be controlled by varying the orientation of the polarization vectors of the light field components with respect to each other and to a magnetic field. In addition, studying the shape of the coherent population trapping resonances for the atoms obtained by photodissociation of molecules may provide information about these molecules.« less

L-type calcium channels refine the neural population code of sound level

PubMed Central

Grimsley, Calum Alex; Green, David Brian

2016-01-01

The coding of sound level by ensembles of neurons improves the accuracy with which listeners identify how loud a sound is. In the auditory system, the rate at which neurons fire in response to changes in sound level is shaped by local networks. Voltage-gated conductances alter local output by regulating neuronal firing, but their role in modulating responses to sound level is unclear. We tested the effects of L-type calcium channels (CaL: CaV1.1–1.4) on sound-level coding in the central nucleus of the inferior colliculus (ICC) in the auditory midbrain. We characterized the contribution of CaL to the total calcium current in brain slices and then examined its effects on rate-level functions (RLFs) in vivo using single-unit recordings in awake mice. CaL is a high-threshold current and comprises ∼50% of the total calcium current in ICC neurons. In vivo, CaL activates at sound levels that evoke high firing rates. In RLFs that increase monotonically with sound level, CaL boosts spike rates at high sound levels and increases the maximum firing rate achieved. In different populations of RLFs that change nonmonotonically with sound level, CaL either suppresses or enhances firing at sound levels that evoke maximum firing. CaL multiplies the gain of monotonic RLFs with dynamic range and divides the gain of nonmonotonic RLFs with the width of the RLF. These results suggest that a single broad class of calcium channels activates enhancing and suppressing local circuits to regulate the sensitivity of neuronal populations to sound level. PMID:27605536

Essential oil variation among natural populations of Lavandula multifida L. (Lamiaceae).

PubMed

Chograni, Hnia; Zaouali, Yosr; Rajeb, Chayma; Boussaid, Mohamed

2010-04-01

Volatiles from twelve wild Tunisian populations of Lavandula multifida L. growing in different bioclimatic zones were assessed by GC (RI) and GC/MS. Thirty-six constituents, representing 83.48% of the total oil were identified. The major components at the species level were carvacrol (31.81%), beta-bisabolene (14.89%), and acrylic acid dodecyl ester (11.43%). These volatiles, together with alpha-pinene, were also the main compounds discriminating the populations. According to these dominant compounds, one chemotype was revealed, a carvacrol/beta-bisabolene/acrylic acid dodecyl ester chemotype. However, a significant variation among the populations was observed for the majority of the constituents. A high chemical-population structure, estimated both by principal component analysis (PCA) and unweighted pair group method with averaging (UPGMA) cluster analysis based on Euclidean distances, was observed. Both methods allowed separation of the populations in three groups defined rather by minor than by major compounds. The population groups were not strictly concordant with their bioclimatic or geographic location. Conservation strategies should concern all populations, because of their low size and their high level of destruction. Populations exhibiting particular compounds other than the major ones should be protected first.

Fundamental trade-offs between information flow in single cells and cellular populations.

PubMed

Suderman, Ryan; Bachman, John A; Smith, Adam; Sorger, Peter K; Deeds, Eric J

2017-05-30

Signal transduction networks allow eukaryotic cells to make decisions based on information about intracellular state and the environment. Biochemical noise significantly diminishes the fidelity of signaling: networks examined to date seem to transmit less than 1 bit of information. It is unclear how networks that control critical cell-fate decisions (e.g., cell division and apoptosis) can function with such low levels of information transfer. Here, we use theory, experiments, and numerical analysis to demonstrate an inherent trade-off between the information transferred in individual cells and the information available to control population-level responses. Noise in receptor-mediated apoptosis reduces information transfer to approximately 1 bit at the single-cell level but allows 3-4 bits of information to be transmitted at the population level. For processes such as eukaryotic chemotaxis, in which single cells are the functional unit, we find high levels of information transmission at a single-cell level. Thus, low levels of information transfer are unlikely to represent a physical limit. Instead, we propose that signaling networks exploit noise at the single-cell level to increase population-level information transfer, allowing extracellular ligands, whose levels are also subject to noise, to incrementally regulate phenotypic changes. This is particularly critical for discrete changes in fate (e.g., life vs. death) for which the key variable is the fraction of cells engaged. Our findings provide a framework for rationalizing the high levels of noise in metazoan signaling networks and have implications for the development of drugs that target these networks in the treatment of cancer and other diseases.

Cost of resistance to trematodes in freshwater snail populations with low clonal diversity.

PubMed

Dagan, Yael; Kosman, Evsey; Ben-Ami, Frida

2017-12-13

The persistence of high genetic variability in natural populations garners considerable interest among ecologists and evolutionary biologists. One proposed hypothesis for the maintenance of high levels of genetic diversity relies on frequency-dependent selection imposed by parasites on host populations (Red Queen hypothesis). A complementary hypothesis suggests that a trade-off between fitness costs associated with tolerance to stress factors and fitness costs associated with resistance to parasites is responsible for the maintenance of host genetic diversity. The present study investigated whether host resistance to parasites is traded off with tolerance to environmental stress factors (high/low temperatures, high salinity), by comparing populations of the freshwater snail Melanoides tuberculata with low vs. high clonal diversity. Since polyclonal populations were found to be more parasitized than populations with low clonal diversity, we expected them to be tolerant to environmental stress factors. We found that clonal diversity explained most of the variation in snail survival under high temperature, thereby suggesting that tolerance to high temperatures of clonally diverse populations is higher than that of populations with low clonal diversity. Our results suggest that resistance to parasites may come at a cost of reduced tolerance to certain environmental stress factors.

High genetic diversity and connectivity in Colossoma macropomum in the Amazon basin revealed by microsatellite markers.

PubMed

Fazzi-Gomes, Paola; Guerreiro, Sávio; Palheta, Glauber David Almeida; Melo, Nuno Filipe Alves Correa de; Santos, Sidney; Hamoy, Igor

2017-01-01

Colossoma macropomum is the second largest scaled fish of the Amazon. It is economically important for commercial fisheries and for aquaculture, but few studies have examined the diversity and genetic structure of natural populations of this species. The aim of this study was to investigate the levels of genetic variability and connectivity that exist between three natural populations of C. macropomum from the Amazon basin. In total, 247 samples were collected from the municipalities of Tefé, Manaus, and Santarém. The populations were genotyped using a panel of 12 multiplex microsatellite markers. The genetic diversity found in these populations was high and similar to other populations described in the literature. These populations showed a pattern of high gene flow associated with the lack of a genetic structure pattern, indicating that the number of migrants per generation and recent migration rates are high. The values of the FST, RST, and exact test of differentiation were not significant for pairwise comparisons between populations. The Bayesian population clustering analysis indicated a single population. Thus, the data provide evidence for high genetic diversity and high gene flow among C. macropomum populations in the investigated region of the Amazon basin. This information is important for programs aiming at the conservation of natural populations.

High genetic diversity and connectivity in Colossoma macropomum in the Amazon basin revealed by microsatellite markers

PubMed Central

Fazzi-Gomes, Paola; Guerreiro, Sávio; Palheta, Glauber David Almeida; de Melo, Nuno Filipe Alves Correa; Santos, Sidney; Hamoy, Igor

2017-01-01

Abstract Colossoma macropomum is the second largest scaled fish of the Amazon. It is economically important for commercial fisheries and for aquaculture, but few studies have examined the diversity and genetic structure of natural populations of this species. The aim of this study was to investigate the levels of genetic variability and connectivity that exist between three natural populations of C. macropomum from the Amazon basin. In total, 247 samples were collected from the municipalities of Tefé, Manaus, and Santarém. The populations were genotyped using a panel of 12 multiplex microsatellite markers. The genetic diversity found in these populations was high and similar to other populations described in the literature. These populations showed a pattern of high gene flow associated with the lack of a genetic structure pattern, indicating that the number of migrants per generation and recent migration rates are high. The values of the FST, RST, and exact test of differentiation were not significant for pairwise comparisons between populations. The Bayesian population clustering analysis indicated a single population. Thus, the data provide evidence for high genetic diversity and high gene flow among C. macropomum populations in the investigated region of the Amazon basin. This information is important for programs aiming at the conservation of natural populations. PMID:28170026

High genetic diversity in the offshore island populations of the tephritid fruit fly Bactrocera dorsalis.

PubMed

Yi, Chunyan; Zheng, Chunyan; Zeng, Ling; Xu, Yijuan

2016-10-13

Geographic isolation is an important factor that limit species dispersal and thereby affects genetic diversity. Because islands are often small and surrounded by a natural water barrier to dispersal, they generally form discrete isolated habitats. Therefore, islands may play a key role in the distribution of the genetic diversity of insects, including flies. To characterize the genetic structure of island populations of Bactrocera dorsalis, we analyzed a dataset containing both microsatellite and mtDNA loci of B. dorsalis samples collected from six offshore islands in Southern China. The microsatellite data revealed a high level of genetic diversity among these six island populations based on observed heterozygosity (Ho), expected heterozygosity (H E ), Nei's standard genetic distance (D), genetic identity (I) and the percentage of polymorphic loci (PIC). These island populations had low F ST values (F ST  = 0.04161), and only 4.16 % of the total genetic variation in the species was found on these islands, as determined by an analysis of molecular variance. Based on the mtDNA COI data, high nucleotide diversity (0.9655) and haplotype diversity (0.00680) were observed in all six island populations. F-statistics showed that the six island populations exhibited low or medium levels of genetic differentiation among some island populations. To investigate the population differentiation between the sampled locations, a factorial correspondence analysis and both the unweighted pair-group method with arithmetic mean and Bayesian clustering methods were used to analyze the microsatellite data. The results showed that Hebao Island, Weizhou Island and Dong'ao Island were grouped together in one clade. Another clade consisted of Shangchuan Island and Naozhou Island, and a final, separate clade contained only the Wailingding Island population. Phylogenetic analysis of the mtDNA COI sequences revealed that the populations on each of these six islands were closely related to different populations on mainland China. Our study suggests that these island populations have high genetic diversity, experience frequent gene flow and exhibit low or medium levels of genetic differentiation among some island populations. Therefore, the geographic isolation of the six islands does not appear to be a major dispersal barrier to B. dorsalis. Such knowledge is helpful for a better understanding of evolutionary processes of the species of island populations.

Complex spatial dynamics maintain northern leopard frog (Lithobates pipiens) genetic diversity in a temporally varying landscape

USGS Publications Warehouse

Mushet, David M.; Euliss, Ned H.; Chen, Yongjiu; Stockwell, Craig A.

2013-01-01

In contrast to most local amphibian populations, northeastern populations of the Northern Leopard Frog (Lithobates pipiens) have displayed uncharacteristically high levels of genetic diversity that have been attributed to large, stable populations. However, this widely distributed species also occurs in areas known for great climatic fluctuations that should be reflected in corresponding fluctuations in population sizes and reduced genetic diversity. To test our hypothesis that Northern Leopard Frog genetic diversity would be reduced in areas subjected to significant climate variability, we examined the genetic diversity of L. pipiens collected from 12 sites within the Prairie Pothole Region of North Dakota. Despite the region's fluctuating climate that includes periods of recurring drought and deluge, we found unexpectedly high levels of genetic diversity approaching that of northeastern populations. Further, genetic structure at a landscape scale was strikingly homogeneous; genetic differentiation estimates (Dest) averaged 0.10 (SD = 0.036) across the six microsatellite loci we studied, and two Bayesian assignment tests (STRUCTURE and BAPS) failed to reveal the development of significant population structure across the 68 km breadth of our study area. These results suggest that L. pipiens in the Prairie Pothole Region consists of a large, panmictic population capable of maintaining high genetic diversity in the face of marked climate variability.

Measles Outbreak in a Vaccinated School Population: Epidemiology, Chains of Transmission and the Role of Vaccine Failures.

ERIC Educational Resources Information Center

Nkowane, Benjamin M.; And Others

1987-01-01

An outbreak of measles occurred in a high school with a documented vaccination level of 98 percent. When measles is introduced in a highly vaccinated population, vaccine failures may play some role in transmission but such transmission is not usually sustained. (Author/LHW)

Recent Fertility Change Among High Fertility Minorities in the United States.

ERIC Educational Resources Information Center

Sweet, James A.

Trends and differentials in fertility for three high fertility minority populations -- Southern rural blacks, Spanish surnamed, and American Indians -- are examined for the intervals between 1957-60 and 1967-70. Fertility levels and patterns of differentials within these three minority populations are also compared with those of the urban white…

New England's Disadvantaged Populations Struggle the Most with Student Debt Repayment

ERIC Educational Resources Information Center

Saas, Darcy Rollins

2016-01-01

Regularly reported statistics about high and growing student-loan debt levels, combined with increased rates of delinquency and default, have prompted calls to address the student-debt "crisis." For New England, with its highly educated population and large higher education industry, student-loan debt is an important economic policy…

Variability of individual genetic load: consequences for the detection of inbreeding depression.

PubMed

Restoux, Gwendal; Huot de Longchamp, Priscille; Fady, Bruno; Klein, Etienne K

2012-03-01

Inbreeding depression is a key factor affecting the persistence of natural populations, particularly when they are fragmented. In species with mixed mating systems, inbreeding depression can be estimated at the population level by regressing the average progeny fitness by the selfing rate of their mothers. We applied this method using simulated populations to investigate how population genetic parameters can affect the detection power of inbreeding depression. We simulated individual selfing rates and genetic loads from which we computed fitness values. The regression method yielded high statistical power, inbreeding depression being detected as significant (5 % level) in 92 % of the simulations. High individual variation in selfing rate and high mean genetic load led to better detection of inbreeding depression while high among-individual variation in genetic load made it more difficult to detect inbreeding depression. For a constant sampling effort, increasing the number of progenies while decreasing the number of individuals per progeny enhanced the detection power of inbreeding depression. We discuss the implication of among-mother variability of genetic load and selfing rate on inbreeding depression studies.

Phytate levels and bone parameters: a retrospective pilot clinical trial.

PubMed

Lopez-Gonzalez, Angel A; Grases, Felix; Perello, Joan; Tur, Fernando; Costa-Bauza, Antonia; Monroy, Nieves; Mari, Bartolome; Vicente-Herrero, Teofila

2010-06-01

This study evaluated the relationship between phytate urinary levels and bone characteristics in a large population of postmenopausal women. The study population consisted of 180 postmenopausal women who participated in a descriptive cross-sectional study. A urine sample was collected from each subject to determine phytate levels and the volunteers were divided into two groups according to phytate urinary concentration (i.e., low and high levels). Bone mineral density was determined in the lumbar spine and femoral neck of groups with low and high phytate urinary levels. Urinary levels of phytate were linked to dietary phytate consumption. Hence, bone mineral density values were significantly higher in the lumbar spines and femoral necks of women who consumed high levels of phytate than in women with low urinary phytate concentrations. Higher urinary levels of phytate correlated with higher bone mineral density in the lumbar spine and femoral necks of postmenopausal women. This finding demonstrates the potential use of phytate in the treatment of bone related diseases, as it uses a mechanism of action similar to some bisphosphonates.

Trends in Water Level and Flooding in Dhaka, Bangladesh and Their Impact on Mortality

PubMed Central

Thiele-Eich, Insa; Burkart, Katrin; Simmer, Clemens

2015-01-01

Climate change is expected to impact flooding in many highly populated coastal regions, including Dhaka (Bangladesh), which is currently among the fastest growing cities in the world. In the past, high mortality counts have been associated with extreme flood events. We first analyzed daily water levels of the past 100 years in order to detect potential shifts in extremes. A distributed lag non-linear model was then used to examine the connection between water levels and mortality. Results indicate that for the period of 2003–2007, which entails two major flood events in 2004 and 2007, high water levels do not lead to a significant increase in relative mortality, which indicates a good level of adaptation and capacity to cope with flooding. However, following low water levels, an increase in mortality could be found. As our trend analysis of past water levels shows that minimum water levels have decreased during the past 100 years, action should be taken to ensure that the exposed population is also well-adapted to drought. PMID:25648177

Genetic diversity of populations and clones of Rhopilema esculentum in China based on AFLP analysis

NASA Astrophysics Data System (ADS)

Qiao, Hongjin; Liu, Xiangquan; Zhang, Xijia; Jiang, Haibin; Wang, Jiying; Zhang, Limin

2013-03-01

Amplified fragment length polymorphisms (AFLP) markers were developed to assess the genetic variation of populations and clones of Rhopilema esculentum Kishinouye (Scyphozoa, Rhizostomatidae). One hundred and seventy-nine loci from 56 individuals of two hatchery populations and two wild populations were genotyped with five primer combinations. The polymorphic ratio, Shannon's diversity index and average heterozygosity were 70.3%, 0.346 and 0.228 for the white hatchery population, 74.3%, 0.313, and 0.201 for the red hatchery population, 79.3%, 0.349, and 0.224 for the Jiangsu wild population, and 74.9%, 0.328 and 0.210 for the Penglai wild population, respectively. Thus, all populations had a relatively high level of genetic diversity. A specific band was identified that could separate the white from the red hatchery population. There was 84.85% genetic differentiation within populations. Individual cluster analysis using unweighted pair-group method with arithmetic mean (UPGMA) suggested that hatchery populations and wild populations could be divided. For the hatchery populations, the white and red populations clustered separately; however, for the wild populations, Penglai and Jiangsu populations clustered together. The genetic diversity at the clone level was also determined. Our data suggest that there are relatively high genetic diversities within populations but low genetic differentiation between populations, which may be related to the long-term use of germplasm resources from Jiangsu Province for artificial seeding and releasing. These findings will benefit the artificial seeding and conservation of the germplasm resources.

Population-level preferences for primary care physicians' characteristics in Japan: a structural equation modeling.

PubMed

Takahashi, Osamu; Ohde, Sachiko; Jacobs, Joshua L; Tokuda, Yasuharu; Yanai, Haruo; Okubo, Tomoya; Shimbo, Takuro; Fukuhara, Shunichi; Hinohara, Shigeaki; Fukui, Tsuguya

2010-01-01

Primary care has potential to play a role for improving the patient care in Japanese health care system; however, little information is available about how patients perceive the roles of primary care physicians (PCPs) within the Japanese health care system. We aimed to assess population-level preferences for PCPs and investigated the extent to which preferences vary in relation to different population groups in Japan. Data were extracted from a cross-sectional questionnaire survey in October 2003. An 18-item questionnaire was used to measure the preferences for PCPs. Exploratory factor analysis was performed to identify latent factors, while confirmatory factor analysis was used to evaluate the fit of the structure using structural equation modeling (SEM). Nationally representative sample of the adult Japanese general population was chosen by controlling for age, sex, and the size of cities. A total of 2,453 adults>or=18-years-old were analyzed. SEM provided a 4-factor structural model of the population-level preference for PCPs, such as clinical competence (path coefficient (pc)=0.72), gate-keeping (pc=0.64), communication with patients or specialists (pc=0.49) and high education (pc=0.25) and demonstrated the best goodness-of-fit. Those who were middle aged, have a high family income, and a high level of education, placed more importance on gate-keeping characteristics, and the rural residents emphasized communication rather than clinical competence. Our results indicate that the preferences for PCPs are divided into four main factors and underscore the variation among preferences according to different population groups, such as age, socioeconomic and educational status, and places of living. These variations should be considered to improve the primary care system in Japan.

Molecular Phylogeny and Phylogeography of the Australian Freshwater Fish Genus Galaxiella, with an Emphasis on Dwarf Galaxias (G. pusilla)

PubMed Central

Unmack, Peter J.; Bagley, Justin C.; Adams, Mark; Hammer, Michael P.; Johnson, Jerald B.

2012-01-01

The freshwater fauna of Southern Australia is primarily restricted to the southwestern and southeastern corners of the continent, and is separated by a large, arid region that is inhospitable to this biota. This geographic phenomenon has attracted considerable interest from biogeographers looking to explain evolutionary diversification in this region. Here, we employed phylogenetic and phylogeographic approaches to evaluate the effect of this barrier on a group of four galaxiid fish species (Galaxiella) endemic to temperate Southern Australia. We also tested if continental shelf width has influenced connectivity among populations during low sea levels when rivers, now isolated, could have been connected. We addressed these questions by sampling each species across its range using multiple molecular markers (mitochondrial cytochrome b sequences, nuclear S7 intron sequences, and 49 allozyme loci). These data also allowed us to assess species boundaries, to refine phylogenetic affinities, and to estimate species ages. Interestingly, we found compelling evidence for cryptic species in G. pusilla, manifesting as allopatric eastern and western taxa. Our combined phylogeny and dating analysis point to an origin for the genus dating to the early Cenozoic, with three of the four species originating during the Oligocene-Miocene. Each Galaxiella species showed high levels of genetic divergences between all but the most proximate populations. Despite extensive drainage connections during recent low sea levels in southeastern Australia, populations of both species within G. pusilla maintained high levels of genetic structure. All populations experienced Late Pleistocene-Holocene population growth, possibly in response to the relaxation of arid conditions after the last glacial maximum. High levels of genetic divergence and the discovery of new cryptic species have important implications for the conservation of this already threatened group of freshwater species. PMID:22693638

Molecular phylogeny and phylogeography of the Australian freshwater fish genus Galaxiella, with an emphasis on dwarf galaxias (G. pusilla).

PubMed

Unmack, Peter J; Bagley, Justin C; Adams, Mark; Hammer, Michael P; Johnson, Jerald B

2012-01-01

The freshwater fauna of Southern Australia is primarily restricted to the southwestern and southeastern corners of the continent, and is separated by a large, arid region that is inhospitable to this biota. This geographic phenomenon has attracted considerable interest from biogeographers looking to explain evolutionary diversification in this region. Here, we employed phylogenetic and phylogeographic approaches to evaluate the effect of this barrier on a group of four galaxiid fish species (Galaxiella) endemic to temperate Southern Australia. We also tested if continental shelf width has influenced connectivity among populations during low sea levels when rivers, now isolated, could have been connected. We addressed these questions by sampling each species across its range using multiple molecular markers (mitochondrial cytochrome b sequences, nuclear S7 intron sequences, and 49 allozyme loci). These data also allowed us to assess species boundaries, to refine phylogenetic affinities, and to estimate species ages. Interestingly, we found compelling evidence for cryptic species in G. pusilla, manifesting as allopatric eastern and western taxa. Our combined phylogeny and dating analysis point to an origin for the genus dating to the early Cenozoic, with three of the four species originating during the Oligocene-Miocene. Each Galaxiella species showed high levels of genetic divergences between all but the most proximate populations. Despite extensive drainage connections during recent low sea levels in southeastern Australia, populations of both species within G. pusilla maintained high levels of genetic structure. All populations experienced Late Pleistocene-Holocene population growth, possibly in response to the relaxation of arid conditions after the last glacial maximum. High levels of genetic divergence and the discovery of new cryptic species have important implications for the conservation of this already threatened group of freshwater species.

Prevalence of food sensitization and probable food allergy among adults in India: the EuroPrevall INCO study.

PubMed

Mahesh, P A; Wong, Gary W K; Ogorodova, L; Potts, J; Leung, T F; Fedorova, O; Holla, Amrutha D; Fernandez-Rivas, M; Clare Mills, E N; Kummeling, I; Versteeg, S A; van Ree, R; Yazdanbakhsh, M; Burney, P

2016-07-01

Data are lacking regarding the prevalence of food sensitization and probable food allergy among general population in India. We report the prevalence of sensitization and probable food allergy to 24 common foods among adults from general population in Karnataka, South India. The study was conducted in two stages: a screening study and a case-control study. A total of 11 791 adults in age group 20-54 were randomly sampled from general population in South India and answered a screening questionnaire. A total of 588 subjects (236 cases and 352 controls) participated in the case-control study involving a detailed questionnaire and specific IgE estimation for 24 common foods. A high level of sensitization (26.5%) was observed for most of the foods in the general population, higher than that observed among adults in Europe, except for those foods that cross-react with birch pollen. Most of the sensitization was observed in subjects who had total IgE above the median IgE level. A high level of cross-reactivity was observed among different pollens and foods and among foods. The prevalence of probable food allergy (self-reports of adverse symptoms after the consumption of food and specific IgE to the same food) was 1.2%, which was mainly accounted for cow's milk (0.5%) and apple (0.5%). Very high levels of sensitization were observed for most foods, including those not commonly consumed in the general population. For the levels of sensitization, the prevalence of probable food allergy was low. This disassociation needs to be further explored in future studies. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Biomonitoring of urinary metals in a population living in the vicinity of industrial sources: a comparison with the general population of Andalusia, Spain.

PubMed

Aguilera, Inmaculada; Daponte, Antonio; Gil, Fernando; Hernández, Antonio F; Godoy, Patricia; Pla, Antonio; Ramos, Juan Luis

2008-12-15

The Ria of Huelva (south-west Spain) is one of the most polluted fluvial-estuarine systems in the world. Industrial activity delivers huge amounts of pollutants to the local environment, particularly heavy metals and arsenic. Here we aimed to determine urinary levels of As, Cd, Cr, Cu and Ni in a representative sample (n=857) of adults living in the Ria of Huelva. Levels were compared to those from a representative sample of 861 adults of the general urban population of Andalusia (southern Spain) and multiple regression models were developed to identify individual factors associated with urinary levels of these elements. Arsenic levels were significantly higher in the Ria of Huelva as compared to other Andalusian cities, whereas Cd and Ni levels were significantly lower. Despite these differences, levels in both groups were similar to the reference values reported in previous studies for general population. Age, gender, diet and lifestyle were the major factors contributing to the interindividual variation in urinary metals. In conclusion, despite living in a highly polluted area, the population of the Ria of Huelva failed to show higher urinary levels of the studied metals as compared to a reference urban population of the same region.

Critical Factors That Influence the Success of Cultivating Seed Teachers in Environmental Education

ERIC Educational Resources Information Center

Hsueh, Sung-Lin; Su, Fu-Long

2016-01-01

Taiwan is a densely populated industrialized country with high-polluting industries. In particular, petrochemical, steel, thermal power, and electronics plants consume a high level of energy. Furthermore, vehicle exhaust emissions are a major contributor to pollution. Collectively, these problems have resulted in high levels of greenhouse gas…

Double Trouble at High Density: Cross-Level Test of Resource-Related Adaptive Plasticity and Crowding-Related Fitness

PubMed Central

Gergs, André; Preuss, Thomas G.; Palmqvist, Annemette

2014-01-01

Population size is often regulated by negative feedback between population density and individual fitness. At high population densities, animals run into double trouble: they might concurrently suffer from overexploitation of resources and also from negative interference among individuals regardless of resource availability, referred to as crowding. Animals are able to adapt to resource shortages by exhibiting a repertoire of life history and physiological plasticities. In addition to resource-related plasticity, crowding might lead to reduced fitness, with consequences for individual life history. We explored how different mechanisms behind resource-related plasticity and crowding-related fitness act independently or together, using the water flea Daphnia magna as a case study. For testing hypotheses related to mechanisms of plasticity and crowding stress across different biological levels, we used an individual-based population model that is based on dynamic energy budget theory. Each of the hypotheses, represented by a sub-model, is based on specific assumptions on how the uptake and allocation of energy are altered under conditions of resource shortage or crowding. For cross-level testing of different hypotheses, we explored how well the sub-models fit individual level data and also how well they predict population dynamics under different conditions of resource availability. Only operating resource-related and crowding-related hypotheses together enabled accurate model predictions of D. magna population dynamics and size structure. Whereas this study showed that various mechanisms might play a role in the negative feedback between population density and individual life history, it also indicated that different density levels might instigate the onset of the different mechanisms. This study provides an example of how the integration of dynamic energy budget theory and individual-based modelling can facilitate the exploration of mechanisms behind the regulation of population size. Such understanding is important for assessment, management and the conservation of populations and thereby biodiversity in ecosystems. PMID:24626228

LPA and PLG sequence variation and kringle IV-2 copy number in two populations.

PubMed

Crawford, Dana C; Peng, Ze; Cheng, Jan-Fang; Boffelli, Dario; Ahearn, Magdalena; Nguyen, Dan; Shaffer, Tristan; Yi, Qian; Livingston, Robert J; Rieder, Mark J; Nickerson, Deborah A

2008-01-01

Lp(a) levels have long been recognized as a potential risk factor for coronary heart disease that is almost completely under genetic control. Much of the genetics impacting Lp(a) levels has been attributed to the highly polymorphic LPA kringle IV-2 copy number variant, and most of the variance in Lp(a) levels in populations of European-descent is inversely correlated with kringle IV copy number. However, less of the variance is explained in African-descent populations for the same structural variation. African-descent populations have, on average, higher levels of Lp(a), suggesting other genetic factors contribute to Lp(a) level variability across populations. To identify potential cis-acting factors, we re-sequenced the gene LPA for single nucleotide polymorphism (SNP) discovery in 23 European-Americans and 24 African-Americans. We also re- sequenced the neighboring gene plasminogen (PLG) and genotyped the kringle IV copy number variant in the same reference samples. These data are the most comprehensive description of sequence variation in LPA and its relationship with the kringle IV copy number variant. With these data, we demonstrate that only a fraction of LPA sequence diversity has been previously documented. Also, we identify several high frequency SNPs present in the African-American sample but absent in the European-American sample. Finally, we show that SNPs within PLG are not in linkage disequilibrium with SNPs in LPA, and we show that kringle IV copy number variation is not in linkage disequilibrium with either LPA or PLG SNPs. Together, these data suggest that LPA SNPs could independently contribute to Lp(a) levels in the general population. Copyright (c) 2008 S. Karger AG, Basel.

Cancer stem-like cells of ovarian clear cell carcinoma are enriched in the ALDH-high population associated with an accelerated scavenging system in reactive oxygen species.

PubMed

Mizuno, T; Suzuki, N; Makino, H; Furui, T; Morii, E; Aoki, H; Kunisada, T; Yano, M; Kuji, S; Hirashima, Y; Arakawa, A; Nishio, S; Ushijima, K; Ito, K; Itani, Y; Morishige, K

2015-05-01

In ovarian cancer cases, recurrence after chemotherapy is frequently observed, suggesting the involvement of ovarian cancer stem-like cells (CSCs). The chemoresistance of ovarian clear cell carcinomas is particularly strong in comparison to other epithelial ovarian cancer subtypes. We investigated the relationship between a CSC marker, aldehyde dehydrogenase 1 (ALDH1), and clinical prognosis using ovarian clear cell carcinoma tissue samples. Furthermore, we investigated the antioxidant mechanism by which CSCs maintain a lower reactive oxygen species (ROS) level, which provides protection from chemotherapeutic agents. Immunohistochemical staining was performed to examine the CSC markers (CD133, CD44, ALDH1) using ovarian clear cell carcinoma tissue samples (n=81). Clear cell carcinoma cell lines (KOC-7C, OVTOKO) are separated into the ALDH-high and ALDH-low populations by ALDEFLUOR assay and fluorescence-activated cell sorting (FACS). We compared the intracellular ROS level, mRNA level of the antioxidant enzymes and Nrf2 expression of the two populations. High ALDH1 expression levels are related to advanced stage in clear cell carcinoma cases. ALDH1 expression significantly reduced progression free survival. Other markers are not related to clinical stage and prognosis. ALDH-high cells contained a lower ROS level than ALDH-low cells. Antioxidant enzymes were upregulated in ALDH-high cells. ALDH-high cells showed increased expression of Nrf2, a key transcriptional factor of the antioxidant system. ALDH-positive CSCs might have increased Nrf2-induced antioxidant scavengers, which lower ROS level relevant to chemoresistance in ovarian clear cell carcinoma. Copyright © 2014 Elsevier Inc. All rights reserved.

Levels of taurine introgression in the current Brazilian Nelore and Gir indicine cattle populations

USDA-ARS?s Scientific Manuscript database

A high density panel of more than 777000 genome-wide single nucleotide polymorphisms (SNPs) were used to investigate the population structure of Nelore and Gir, compared to seven other populations worldwide. Principal Component Analysis and model-based ancestry estimation clearly separate the indici...

Population-Wide Parenting Intervention Training: Initial Feasibility

ERIC Educational Resources Information Center

Shapiro, Cheri J.; Prinz, Ronald J.; Sanders, Matthew R.

2008-01-01

A population-level approach to deliver parenting and family support is a necessary but neglected approach needed to reduce the high prevalence of emotional/behavioral problems in children, decrease inadequate and potentially abusive parenting practices, and to provide improved parenting support to all parents within a specified population. We…

Estimation of high risk pregnancy contributing to perinatal morbidity and mortality from a birth population-based regional survey in 2010 in China.

PubMed

Sun, Libo; Yue, Hongni; Sun, Bo; Han, Liangrong; Tian, Zhaofang; Qi, Meihua; Lu, Shuyan; Shan, Chunming; Luo, Jianxin; Fan, Yujing; Li, Shouzhong; Dong, Maotian; Zuo, Xiaofeng; Zhang, Yixing; Lin, Wenlong; Xu, Jinzhong; Heng, Yongbo

2014-09-30

Neonatal mortality reduction in China over past two decades was reported from nationwide sampling surveys, however, how high risk pregnancy affected neonatal outcome is unknown. The objective of this study was to explore relations of pregnancy complications and neonatal outcomes from a regional birth population. In a prospective, cross-sectional survey of complete birth population-based data file from 151 level I-III hospitals in Huai'an region in 2010, pregnancy complications were analyzed for perinatal morbidity and mortality in association with maternal and perinatal characteristics, hospital levels, mode of delivery, newborn birth weight and gestational age, using international definition for birth registry and morbidities. Pregnancy complications were found in 10% of all births, in which more than 70% were delivered at level II and III hospitals associated with higher proportions of fetal and neonatal death, preterm birth, death at delivery and congenital anomalies. High Cesarean section delivery was associated with higher pregnancy complications, and more neonatal critical illnesses. The pregnancy complications related perinatal morbidity and mortality in level III were 2-4 times as high as in level I and II hospitals. By uni- and multi-variate regression analysis, impact of pregnancy complications was along with congenital anomalies and preterm birth, and maternal child-bearing age and school education years contributing to the prevalence. This survey revealed variable links of pregnancy complications to perinatal outcome in association with very high Cesarean section deliveries, which warrants investigation for causal relations between high risk pregnancy and neonatal outcome in this emerging region.

Placental Growth Factor Levels in Populations with High Versus Low Risk for Cardiovascular Disease and Stressful Physiological Environments such as Microgravity: A Pilot Study

NASA Astrophysics Data System (ADS)

Sundaresan, Alamelu; Mehta, Satish K.; Schlegel, Todd. T.; Russomano, Thais; Pierson, Duane L.; Mann, Vivek; Mansoor, Elvedina; Olamigoke, Loretta; Okoro, Elvis

2017-02-01

This pilot study compared placental growth factor (PIGF) levels in populations with high versus low risk for cardiovascular disease. Previous experiments from our laboratory (Sundaresan et al. 2005, 2009) revealed that the angiogenic factor PIGF was up regulated in modeled microgravity conditions in human lymphocytes leading to possible atherogenesis and pathogenesis in microgravity. Since the findings came from microgravity analog experiments, there is a strong link to its usefulness in the microgravity field as a biomarker. It is important to understand, that these findings came from both studies on expression levels of this cardiovascular marker in human lymphocytes in microgravity ( in vitro microgravity analog), and a follow up gene expression study in hind limb suspended mice ( in vivo microgravity analog). The relevance is enhanced because in life on earth, PIGF is an inflammatory biomarker for cardiovascular disease. Studies on the levels of PIGF would help to reduce the risk and prevention of heart failures in astronauts. If we can use this marker to predict and reduce the risk of cardiac events in astronauts and pilots, it would significantly help aerospace medicine operations. The investigations here confirmed that in a cardiovascular stressed population such as coronary artery disease (CAD) and acute coronary syndrome (ACS) patients, PIGF could be overexpressed. We desired to re-evaluate this marker in patients with cardiovascular disease in our own study. PIGF is a marker of inflammation and a predictor of short-term and long-term adverse outcome in ACS. In addition, elevated PIGF levels may be associated with increased risk for CAD.PIGF levels were determined in thirty-one patients undergoing cardiovascular catheterization for reasons other than ACS and in thirty-three low-risk asymptomatic subjects. Additional data on traditional cardiovascular risk factors for both populations were also compiled and compared. We found that PIGF levels were significantly higher in the high-risk population as compared to low-risk population. Also we were able to ascertain that PIGF levels were inversely correlated with HDL-cholesterol but directly correlated with the triglyceride levels. With further validation, PIGF may prove a useful addition to the armamentarium of noninvasive biomarkers for cardiovascular disease including a new area of stressful physiological conditions such as microgravity.

Which population groups are most unaware of CVD risks associated with sitting time?

PubMed

Duncan, Mitch J; Gilson, Nicholas; Vandelanotte, Corneel

2014-08-01

Prolonged sitting is an emerging risk factor for poor health yet few studies have examined awareness of the risks associated with sitting behaviours. This study identifies the population subgroups with the highest levels of unawareness regarding the cardiovascular disease (CVD) risks associated with sitting behaviours. Adults (n=1256) living in Queensland, Australia completed a telephone-based survey in 2011, analysis conducted in 2013. The survey assessed participant's socio-demographic characteristics, physical activity, sitting behaviours and awareness of CVD risks associated with three sitting behaviours: 1) sitting for prolonged periods, 2), sitting for prolonged periods whilst also engaging in regular physical activity, and 3) breaking up periods of prolonged sitting with short activity breaks. Population sub-groups with the highest levels of unawareness were identified based on socio-demographic and behavioural characteristics using signal detection analysis. Unawareness ranged from 23.3% to 67.0%. Age was the most important variable in differentiating awareness levels; younger adults had higher levels of unawareness. Body mass index, physical activity, TV viewing, employment status and time spent at work also identified population sub-groups. Unawareness of CVD risk for prolonged sitting was moderately high overall. Younger adults had high levels of unawareness on all of the outcomes examined. Copyright © 2014 Elsevier Inc. All rights reserved.

Ultrashort-pulse-train pump and dump excitation of a diatomic molecule

NASA Astrophysics Data System (ADS)

de Araujo, Luís E. E.

2010-09-01

An excitation scheme is proposed for transferring population between ground-vibrational levels of a molecule. The transfer is accomplished by pumping and dumping population with a pair of coherent ultrashort-pulse trains via a stationary state. By mismatching the teeth of the frequency combs associated with the pulse trains to the vibrational levels, high selectivity in the excitation, along with high transfer efficiency, is predicted. The pump-dump scheme does not suffer from spontaneous emission losses, it is insensitive to the pump-dump-train delay, and it requires only basic pulse shaping.

Ultrashort-pulse-train pump and dump excitation of a diatomic molecule

DOE Office of Scientific and Technical Information (OSTI.GOV)

Araujo, Luis E. E. de

An excitation scheme is proposed for transferring population between ground-vibrational levels of a molecule. The transfer is accomplished by pumping and dumping population with a pair of coherent ultrashort-pulse trains via a stationary state. By mismatching the teeth of the frequency combs associated with the pulse trains to the vibrational levels, high selectivity in the excitation, along with high transfer efficiency, is predicted. The pump-dump scheme does not suffer from spontaneous emission losses, it is insensitive to the pump-dump-train delay, and it requires only basic pulse shaping.

Levels and sources of forest fire prevention knowledge of California hunters

Treesearch

William S. Folkman

1963-01-01

Males 30-50 years of age from the smaller urban centers (under 25,000 population) make up the bulk of the California hunter population. They are mainly from the skilled-semiskilled and professional-managerial occupations. Their level of knowledge about forest fire prevention is generally high, but their knowledge is weak in some pertinent areas. Most frequently...

Psychological, behavioral, and family characteristics of pediatric patients with chronic pain: a 1-year retrospective study and cluster analysis.

PubMed

Scharff, Lisa; Langan, Nicole; Rotter, Nancy; Scott-Sutherland, Jennifer; Schenck, Clorinda; Tayor, Neil; McDonald-Nolan, Lori; Masek, Bruce

2005-01-01

There has been a longstanding recognition that adult patients with chronic pain are not a homogenous population and that there are subgroups of patients who report high levels of distress and interpersonal difficulties as well as subgroups of patients who report little distress and high functioning. The purpose of the present study was to attempt to identify similar subgroups in a pediatric chronic pain population. The sample consisted of 117 children with chronic pain and their parents who were assessed in a multidisciplinary pain clinic during 2001. Participants completed a set of psychologic self-report questionnaires, as well as demographic and pain characteristic information. A cluster analysis was conducted to identify 3 distinct subgroups of patients to replicate similar studies of adult chronic pain sufferers. Overall, mean scores were within population norms on measures of distress and family functioning, with somatic symptoms at a level of clinical significance. The cluster analysis identified the 3 subgroups that were strikingly similar to those identified in adult chronic pain populations: one with high levels of distress and disability, another with relatively low scores on distress and disability, and a third group that scored in between the other 2 on these measures but with marked low family cohesion. The similarity of these subgroups to the adult chronic pain population subgroups as well as implications for future studies are discussed.

Comparison of general health status, myocardial infarction, obesity, diabetes, and fruit and vegetable intake between immigrant Pakistani population in the Netherlands and the local Amsterdam population.

PubMed

Raza, Qaisar; Nicolaou, Mary; Dijkshoorn, Henriëtte; Seidell, Jacob C

2017-12-01

South Asians living in Western countries have shown higher prevalence of cardiovascular disease and related non-communicable diseases as compared to the local populations. The aim of this study was to compare the general health status and prevalence of myocardial infarction (MI), diabetes, high blood pressure, overweight, obesity, and fruit and vegetable intake between Pakistani immigrants in the Netherlands and local Amsterdam population. A health survey was conducted in 2012-2013 among Pakistanis in the Netherlands. Results were compared with a health survey conducted among inhabitants of Amsterdam in 2012. One hundred and fifty-four Pakistanis from four big cities of the Netherlands and 7218 inhabitants of Amsterdam participated. The data for Amsterdam population were weighed on the basis of age, gender, city district, marital status, ethnicity and income level while the data for Pakistanis were weighed on the basis of age and gender to make both data-sets representative of their general population. Pakistanis reported a high prevalence of MI (3.3%), diabetes (11.4%), high blood pressure (14.4%), overweight (35.5%) and obesity (18.5%) while Amsterdam population reported the prevalence as 2.5% for MI, 6.8% for diabetes, 15.3% for high blood pressure, 28.1% for overweight and 11.1% for obesity. Pakistanis had a significantly higher level of MI (OR = 2.71; 95% CI: 1.19-6.14), diabetes (OR = 4.41; 95% CI: 2.66-7.33) and obesity (OR = 2.51; 95% CI: 1.53-4.12) after controlling for age, sex and educational level with Amsterdam population as the reference group. Pakistanis showed a higher intake of fruit and fruit juice as compared to Amsterdam population though the latter showed a higher intake of cooked vegetables. Higher prevalence of MI, diabetes and obesity among Pakistanis than Amsterdam population indicates the need for health scientists and policy-makers to develop interventions for tackling non-communicable diseases and its determinants among Pakistanis living in the Netherlands.

Local level epidemiological analysis of TB in people from a high incidence country of birth.

PubMed

Massey, Peter D; Durrheim, David N; Stephens, Nicola; Christensen, Amanda

2013-01-22

The setting for this analysis is the low tuberculosis (TB) incidence state of New South Wales (NSW), Australia. Local level analysis of TB epidemiology in people from high incidence countries-of-birth (HIC) in a low incidence setting has not been conducted in Australia and has not been widely reported. Local level analysis could inform measures such as active case finding and targeted earlier diagnosis. The aim of this study was to use a novel approach to identify local areas in an Australian state that have higher TB rates given the local areas' country of birth profiles. TB notification data for the three year period 2006-2008 were analysed by grouping the population into those from a high-incidence country-of-birth and the remainder. During the study period there were 1401 notified TB cases in the state of NSW. Of these TB cases 76.5% were born in a high-incidence country. The annualised TB notification rate for the high-incidence country-of-birth group was 61.2/100,000 population and for the remainder of the population was 1.8/100,000. Of the 152 Local Government Areas (LGA) in NSW, nine had higher and four had lower TB notification rates in their high-incidence country-of-birth populations when compared with the high-incidence country-of-birth population for the rest of NSW. The nine areas had a higher proportion of the population with a country of birth where TB notification rates are >100/100,000. Those notified with TB in the nine areas also had a shorter length of stay in Australia than the rest of the state. The areas with higher TB notification rates were all in the capital city, Sydney. Among LGAs with higher TB notification rates, four had higher rates in both people with a high-incidence country of birth and people not born in a high-incidence country. The age distribution of the HIC population was similar across all areas, and the highest differential in TB rates across areas was in the 5-19 years age group. Analysing local area TB rates and possible explanatory variables can provide useful insights into the epidemiology of TB. TB notification rates that take country of birth in local areas into account could enable health services to strategically target TB control measures.

Accumulation and potential health effects of organohalogenated compounds in the arctic fox (Vulpes lagopus)--a review.

PubMed

Pedersen, Kathrine Eggers; Styrishave, Bjarne; Sonne, Christian; Dietz, Rune; Jenssen, Bjørn Munro

2015-01-01

This review addresses biological effects of anthropogenic organohalogenated compounds in the arctic fox (Vulpes lagopus). When considering the current levels, spatial and tissue distributions of selected organic pollutants in arctic fox subpopulations, especially the Svalbard based populations accumulate high levels. The dominating contaminant groups are the polychlorinated biphenyls (PCBs) and chlordanes (CHLs), which reach high levels in adipose tissues, adrenals and liver. Recent controlled exposure studies on domesticated arctic fox and Greenland sledge dogs, show adverse health effects associated with OC concentrations lower than those measured in free-ranging populations. This indicates that especially populations at Svalbard may be at risk of experiencing OC related effects. The arctic fox as such may be an overlooked species in the Arctic Monitoring and Assessment Programs and it would add further information about pollution in the Arctic to include this species in the monitoring program. Copyright © 2014 Elsevier B.V. All rights reserved.

Plasma folate levels in early to mid pregnancy after a nation-wide folic acid supplementation program in areas with high and low prevalence of neural tube defects in China.

PubMed

Liu, Jufen; Gao, Lili; Zhang, Yali; Jin, Lei; Li, Zhiwen; Zhang, Le; Meng, Qinqin; Ye, Rongwei; Wang, Linlin; Ren, Aiguo

2015-06-01

Folic acid supplementation is recommended for all women of child-bearing age to prevent neural tube defects (NTDs). A nation-wide folic acid supplementation program was implemented in rural areas of China since 2009; however, changes in plasma folate levels in pregnant women were unknown. A cross-sectional survey was conducted in 2011 to 2012, with 1736 pregnant women enrolled, and results were compared with a previous survey in 2002 to 2004. A microbiological method was used to determine plasma folate levels. Preprogram and postprogram median plasma folate concentrations were compared while stratified by prevalence of NTDs and residence. In the high NTD prevalence population, plasma folate concentration increased to 33.4 (18.7, 58.4) nmol/L in the postprogram sample, which is 2.9 times of the preprogram. In the low NTD prevalence population, plasma folate increased to 67.9 (44.5, 101.9) nmol/L, which is 1.9 times of the preprogram. Gaps remained in plasma folate levels with respect to prevalence of NTDs and residence. Folic acid supplementation has a strong impact on plasma folate concentrations. Earlier supplementation (before the last menstrual period), increased supplementation frequency and more total days of supplementation were associated with a higher plasma folate concentration as demonstrated in both the high- and low-prevalence populations. Plasma folate levels among pregnant Chinese women increased dramatically after the nation-wide folic acid supplementation program in both rural and urban areas, and in populations of high and low NTD prevalence. The nation-wide program should have a component to ensure that supplementation begins before pregnancy. © 2015 Wiley Periodicals, Inc.

Betel quid chewing as a source of manganese exposure: total daily intake of manganese in a Bangladeshi population.

PubMed

Al-Rmalli, Shaban W; Jenkins, Richard O; Haris, Parvez I

2011-02-07

A relationship between betel quid chewing in Bangladeshi populations and the development of skin lesions and tremor has been previously reported, for people exposed to high levels of arsenic (As) through drinking contaminated groundwater. Exposure to manganese (Mn) is also known to induce neurotoxicity and levels of Mn in Bangladeshi groundwater are also high. The present study evaluates betel quid chewing as an overlooked source of Mn exposure in a Bangladeshi population. Inductively coupled plasma mass spectrometry (ICP-MS) was used to determine (1) urinary Mn levels for 15 chewers and 22 non-chewers from the ethnic Bangladeshi community in the United Kingdom, and (2) Mn levels in betel quids, its individual components and other Bangladeshi foods. Betel quid chewers displayed a significantly higher (P = 0.009) mean Mn concentration in urine (1.93 μg L(-1)) compared to non-chewers (0.62 μg L(-1)). High levels of Mn were detected in Piper betel leaves with an overall average of 135 mg kg(-1) (range 26 -518 mg kg(-1)). The mean concentration of Mn in betel quid was 41 mg kg(-1) (SD 27) and the daily intake of Mn in the Bangladeshi population was estimated to be 20.3 mg/day. Chewing six betel quids could contribute up to 18% of the maximum recommended daily intake of Mn. We have demonstrated that Mn in betel quids is an overlooked source of exposure to Mn in humans. Chewers display a 3.1 fold increased urinary Mn concentration compared to non-chewers. The practice of betel quid chewing contributes a high proportion of the maximum recommended daily intake of Mn, which could make chewers in Bangladesh more vulnerable to Mn neurotoxicity.

Betel quid chewing as a source of manganese exposure: total daily intake of manganese in a Bangladeshi population

PubMed Central

2011-01-01

Background A relationship between betel quid chewing in Bangladeshi populations and the development of skin lesions and tremor has been previously reported, for people exposed to high levels of arsenic (As) through drinking contaminated groundwater. Exposure to manganese (Mn) is also known to induce neurotoxicity and levels of Mn in Bangladeshi groundwater are also high. The present study evaluates betel quid chewing as an overlooked source of Mn exposure in a Bangladeshi population. Methods Inductively coupled plasma mass spectrometry (ICP-MS) was used to determine (1) urinary Mn levels for 15 chewers and 22 non-chewers from the ethnic Bangladeshi community in the United Kingdom, and (2) Mn levels in betel quids, its individual components and other Bangladeshi foods. Results Betel quid chewers displayed a significantly higher (P = 0.009) mean Mn concentration in urine (1.93 μg L-1) compared to non-chewers (0.62 μg L-1). High levels of Mn were detected in Piper betel leaves with an overall average of 135 mg kg-1 (range 26 -518 mg kg-1). The mean concentration of Mn in betel quid was 41 mg kg-1 (SD 27) and the daily intake of Mn in the Bangladeshi population was estimated to be 20.3 mg/day. Chewing six betel quids could contribute up to 18% of the maximum recommended daily intake of Mn. Conclusion We have demonstrated that Mn in betel quids is an overlooked source of exposure to Mn in humans. Chewers display a 3.1 fold increased urinary Mn concentration compared to non-chewers. The practice of betel quid chewing contributes a high proportion of the maximum recommended daily intake of Mn, which could make chewers in Bangladesh more vulnerable to Mn neurotoxicity. PMID:21299859

Rapid Induction of High-Level Carbapenem Resistance in Heteroresistant KPC-Producing Klebsiella pneumoniae

PubMed Central

Adams-Sapper, Sheila; Nolen, Shantell; Donzelli, Grace Fox; Lal, Mallika; Chen, Kunihiko; Justo da Silva, Livia Helena; Moreira, Beatriz M.

2015-01-01

Enterobacteriaceae strains producing the Klebsiella pneumoniae carbapenemase (KPC) have disseminated worldwide, causing an urgent threat to public health. KPC-producing strains often exhibit low-level carbapenem resistance, which may be missed by automated clinical detection systems. In this study, eight Klebsiella pneumoniae strains with heterogeneous resistance to imipenem were used to elucidate the factors leading from imipenem susceptibility to high-level resistance as defined by clinical laboratory testing standards. Time-kill analysis with an inoculum as low as 3 × 106 CFU/ml and concentrations of imipenem 8- and 16-fold higher than the MIC resulted in the initial killing of 99.9% of the population. However, full recovery of the population occurred by 20 h of incubation in the same drug concentrations. Population profiles showed that recovery was mediated by a heteroresistant subpopulation at a frequency of 2 × 10−7 to 3 × 10−6. Samples selected 2 h after exposure to imipenem were as susceptible as the unexposed parental strain and produced the major outer membrane porin OmpK36. However, between 4 to 8 h after exposure, OmpK36 became absent, and the imipenem MIC increased at least 32-fold. Individual colonies isolated from cultures after 20 h of exposure revealed both susceptible and resistant subpopulations. Once induced, however, the high-level imipenem resistance was maintained, and OmpK36 remained unexpressed even without continued carbapenem exposure. This study demonstrates the essential coordination between blaKPC and ompK36 expression mediating high-level imipenem resistance from a population of bacteria that initially exhibits a carbapenem-susceptibility phenotype. PMID:25801565

Can human populations be stabilized?

NASA Astrophysics Data System (ADS)

Warren, Stephen G.

2015-02-01

Historical examples of demographic change, in China, Italy, Nigeria, Utah, Easter Island, and elsewhere, together with simple mathematics and biological principles, show that stabilizing world population before it is limited by food supply will be more difficult than is generally appreciated. United Nations population projections are wrong because they assume, in spite of the absence of necessary feedbacks, that all nations will converge rapidly to replacement-level fertility and thereafter remain at that level. Education of women and provision of contraceptives have caused dramatic reductions in fertility, but many groups, including some that are well-educated, maintain high fertility. Small groups with persistent high fertility can grow to supplant low-fertility groups, resulting in continued growth of the total population. The global average fertility rate could rise even if each country's fertility rate is falling. In some low-fertility European countries where deaths exceed births, the population continues to grow because of immigration. Producing more than two offspring is normal for all animal species with stable populations because their populations are limited by resources or predation rather than birth control. It may therefore be appropriate to view the growth of human population as the result not of excess fertility but rather of excess food.

Assessing the roles of population density and predation risk in the evolution of offspring size in populations of a placental fish

PubMed Central

Schrader, Matthew; Travis, Joseph

2012-01-01

Population density is an ecological variable that is hypothesized to be a major agent of selection on offspring size. In high-density populations, high levels of intraspecific competition are expected to favor the production of larger offspring. In contrast, lower levels of intraspecific competition and selection for large offspring should be weaker and more easily overridden by direct selection for increased fecundity in low-density populations. Some studies have found associations between population density and offspring size consistent with this hypothesis. However, their interpretations are often clouded by a number of issues. Here, we use data from a 10-year study of nine populations of the least killifish, Heterandria formosa, to describe the associations of offspring size with habitat type, population density, and predation risk. We found that females from spring populations generally produced larger offspring than females from ponds; however, the magnitude of this difference varied among years. Across all populations, larger offspring were associated with higher densities and lower risks of predation. Interestingly, the associations between the two ecological variables (density and predation risk) and offspring size were largely independent of one another. Our results suggest that previously described genetic differences in offspring size are due to density-dependent natural selection. PMID:22957156

Fitness costs of increased cataract frequency and cumulative radiation dose in natural mammalian populations from Chernobyl.

PubMed

Lehmann, Philipp; Boratyński, Zbyszek; Mappes, Tapio; Mousseau, Timothy A; Møller, Anders P

2016-01-27

A cataract is a clouding of the lens that reduces light transmission to the retina, and it decreases the visual acuity of the bearer. The prevalence of cataracts in natural populations of mammals, and their potential ecological significance, is poorly known. Cataracts have been reported to arise from high levels of oxidative stress and a major cause of oxidative stress is ionizing radiation. We investigated whether elevated frequencies of cataracts are found in eyes of bank voles Myodes glareolus collected from natural populations in areas with varying levels of background radiation in Chernobyl. We found high frequencies of cataracts in voles collected from different areas in Chernobyl. The frequency of cataracts was positively correlated with age, and in females also with the accumulated radiation dose. Furthermore, the number of offspring in female voles was negatively correlated with cataract severity. The results suggest that cataracts primarily develop as a function of ionizing background radiation, most likely as a plastic response to high levels of oxidative stress. It is therefore possible that the elevated levels of background radiation in Chernobyl affect the ecology and fitness of local mammals both directly through, for instance, reduced fertility and indirectly, through increased cataractogenesis.

Ethnicity and health literacy: a survey on hypertension knowledge among Canadian ethnic populations.

PubMed

Cunningham, Ceara Tess; Sykes, Lindsay L; Metcalfe, Amy; Cheng, Amy; Riaz, Muhammad; Lin, Katie; Schorr, Emily; Campbell, Norm R C; Quan, Hude

2014-01-01

With an increase and diversity in ethnic populations in Westernized countries, understanding the differences in levels of knowledge surrounding hypertension is important in planning appropriate prevention strategies. The purpose of our study was to assess levels of hypertension knowledge in Chinese, Indian and White populations in a large metropolitan Canadian city. A telephone survey was conducted in English, Chinese (Cantonese and Mandarin) and Indian languages (Hindi, Punjabi and Urdu). Hypertension knowledge was assessed through a 10-item validated instrument; respondents received 1 point for each correct answer. Logistic regression was used to test differences in hypertension knowledge among these three populations. Survey response rates were 68.7% (301) for Chinese, 61.3% (248) for Indian and 69.7% (254) for White populations. The average hypertension knowledge score for Chinese respondents was 7.23 out of 10, 7.11 for Indian respondents and 7.28 for White respondents. Compared to White respondents, Chinese respondents were less likely than White respondents to know high blood pressure can cause heart attacks (adjusted odds ratio [aOR]: .43, 95% confidence interval [CI]: .19-.96] and Indian respondents were less likely to know losing weight usually decreases blood pressure (aOR: .38, 95% CI: .21-.68). Hypertension knowledge levels among these three ethnic/racial populations were similar and relatively high and varied by content. Low levels of knowledge for Chinese and Indian ethnic populations were on hypertension risk factors, long-term consequences of hypertension and anti-hypertensive medication adherence. Specifically, females, recent immigrants to Canada and Chinese seniors were identified as sub-groups who should be targeted for hypertension knowledge promotion.

Efficiency or equity? Simulating the impact of high-risk and population intervention strategies for the prevention of disease.

PubMed

Platt, Jonathan M; Keyes, Katherine M; Galea, Sandro

2017-12-01

Maximizing both efficiency and equity are core considerations for population health. These considerations can result in tension in population health science as we seek to improve overall population health while achieving equitable health distributions within populations. Limited work has explored empirically the consequences of different population health intervention strategies on the burden of disease and on within- and between-group differences in disease. To address this gap, we compared the impact of four simulated interventions using data from the National Health and Nutrition Examination Survey. In particular, we focus on assessing how population and high-risk primary prevention and population and high-risk secondary interventions efforts to reduce smoking behavior influence systolic blood pressure (SBP) and hypertension, and how such strategies influence inequalities in SBP by income. The greatest reductions in SBP mean and standard deviation resulted from the population secondary prevention. High-risk primary and secondary prevention and population secondary prevention programs all yielded substantial reductions in hypertension prevalence. The effect of population primary prevention did little to decrease population SBP mean and standard deviation, as well as hypertension prevalence. Both high-risk strategies had a larger impact in the low-income population, leading to the greatest narrowing the income-related gap in disease. The population prevention strategies had a larger impact in the high-income population. Population health approaches must consider the potential impact on both the whole population and also on those with different levels of risk for disease within a population, including those in under-represented or under-served groups.

Population genetics of the olive-winged bulbul (Pycnonotus plumosus) in a tropical urban-fragmented landscape.

PubMed

Tang, Grace S Y; Sadanandan, Keren R; Rheindt, Frank E

2016-01-01

With increasing urbanization, urban-fragmented landscapes are becoming more and more prevalent worldwide. Such fragmentation may lead to small, isolated populations that face great threats from genetic factors that affect even avian species with high dispersal propensities. Yet few studies have investigated the population genetics of species living within urban-fragmented landscapes in the Old World tropics, in spite of the high levels of deforestation and fragmentation within this region. We investigated the evolutionary history and population genetics of the olive-winged bulbul (Pycnonotus plumosus) in Singapore, a highly urbanized island which retains <5% of its original forest cover in fragments. Combining our own collected and sequenced samples with those from the literature, we conducted phylogenetic and population genetic analyses. We revealed high genetic diversity, evidence for population expansion, and potential presence of pronounced gene flow across the population in Singapore. This suggests increased chances of long-term persistence for the olive-winged bulbul and the ecosystem services it provides within this landscape.

Genetic variation among wild lake trout populations: the 'wanted' and the 'unwanted'

USGS Publications Warehouse

Burnham-Curtis, Mary K.; Kallemeyn, Larry W.; Bronte, Charles R.; Greswell, Robert E.; Dwyer, Pat; Hamre, R.H.

1997-01-01

In this study we examine genetic variation within and among self-sustaining lake trout populations from the Great Lakes basin, the Rainy Lake basin, and Yellowstone Lake. We used RFLP analysis and direct sequencing to examine DNA sequence variation among several mitochondrial and nuclear genes, including highly conserved loci (e.g. cytochrome b, nuclear exon regions) and highly variable loci (e.g. mitochondrial d-loop and nuclear intron regions). Native Lake Superior lake trout populations show high levels of genetic diversity, while populations from the Rainy Lake basin show little or none. The lake trout population sampled from Yellowstone Lake shows moderate genetic diversity, possibly representative of a relatively large source population closely related to lake trout from Lewis Lake, Wyoming. There has been significant social and management controversy involving these lake trout populations, particularly those that are located in National Parks. In the Great Lakes and Rainy Lake basins, the controversy involves the degree to which hatchery supplementation can contribute to or negatively impact self-sustaining populations which are highly desired by recreational and commercial fisheries. In Yellowstone Lake, the lake trout are viewed as an undesirable intruder that may interfere with resident populations of highly prized native cutthroat trout.

Genetic variation in lipoprotein (a) levels in families enriched for coronary artery disease is determined almost entirely by the apolipoprotein (a) gene locus.

PubMed Central

DeMeester, C A; Bu, X; Gray, R J; Lusis, A J; Rotter, J I

1995-01-01

Lipoprotein (a) (Lp[a]) is a cholesterol-rich lipoprotein resembling LDL but also containing a large polypeptide designated apolipoprotein (a) (apo[a]). Its levels are highly variable among individuals and, in a number of studies, are strongly correlated with the risk of coronary artery disease (CAD). In an effort to determine which genes control Lp(a) levels, we have studied 25 multiplex families (comprising 298 members) enriched for CAD. The apo(a) gene was genotyped among the families, using a highly informative pulse-field gel electrophoresis procedure. In addition, polymorphisms of the gene for the other major protein of Lp(a), apolipoprotein B (apoB), were examined. Quantitative sib-pair linkage analysis indicates that apo(a) is the major gene controlling Lp(a) levels in this CAD population (P = .001; 99 sib pairs), whereas the apoB gene demonstrated no significant quantitative linkage effect. We estimate that the apo(a) locus accounts for < or = 98% of variance of Lp(a) serum levels. Approximately 43% of this variation is explained by size polymorphisms within the apo(a) gene. These results indicate that the apo(a) gene is the major determinant of Lp(a) serum levels not only in the general population but also in a high-risk CAD population. Images Figure 2 PMID:7825589

Modern prescription theory and application: realistic expectations for speech recognition with hearing AIDS.

PubMed

Johnson, Earl E

2013-01-01

A major decision at the time of hearing aid fitting and dispensing is the amount of amplification to provide listeners (both adult and pediatric populations) for the appropriate compensation of sensorineural hearing impairment across a range of frequencies (e.g., 160-10000 Hz) and input levels (e.g., 50-75 dB sound pressure level). This article describes modern prescription theory for hearing aids within the context of a risk versus return trade-off and efficient frontier analyses. The expected return of amplification recommendations (i.e., generic prescriptions such as National Acoustic Laboratories-Non-Linear 2, NAL-NL2, and Desired Sensation Level Multiple Input/Output, DSL m[i/o]) for the Speech Intelligibility Index (SII) and high-frequency audibility were traded against a potential risk (i.e., loudness). The modeled performance of each prescription was compared one with another and with the efficient frontier of normal hearing sensitivity (i.e., a reference point for the most return with the least risk). For the pediatric population, NAL-NL2 was more efficient for SII, while DSL m[i/o] was more efficient for high-frequency audibility. For the adult population, NAL-NL2 was more efficient for SII, while the two prescriptions were similar with regard to high-frequency audibility. In terms of absolute return (i.e., not considering the risk of loudness), however, DSL m[i/o] prescribed more outright high-frequency audibility than NAL-NL2 for either aged population, particularly, as hearing loss increased. Given the principles and demonstrated accuracy of desensitization (reduced utility of audibility with increasing hearing loss) observed at the group level, additional high-frequency audibility beyond that of NAL-NL2 is not expected to make further contributions to speech intelligibility (recognition) for the average listener.

Does vaccination ensure protection? Assessing diphtheria and tetanus antibody levels in a population of healthy children

PubMed Central

Gowin, Ewelina; Wysocki, Jacek; Kałużna, Ewelina; Świątek-Kościelna, Bogna; Wysocka-Leszczyńska, Joanna; Michalak, Michał; Januszkiewicz-Lewandowska, Danuta

2016-01-01

Abstract Vaccination effectiveness is proven when the disease does not develop after a patient is exposed to the pathogen. In the case of rare diseases, vaccination effectiveness is assessed by monitoring specific antibody levels in the population. Such recurrent analyses allow the evaluation of vaccination programs. The primary schedule of diphtheria and tetanus vaccinations is similar in various countries, with differences mainly in the number and timing of booster doses. The aim of the study was to assess diphtheria and tetanus antibody concentrations in a population of healthy children. Diphtheria and tetanus antibody levels were analyzed in a group of 324 children aged 18 to 180 months. All children were vaccinated in accordance with the Polish vaccination schedule. Specific antibody concentrations greater than 0.1 IU/mL were considered protective against tetanus or diphtheria. Levels above 1.0 were considered to ensure long-term protection. Protective levels of diphtheria antibodies were found in 229 patients (70.46%), and of tetanus in 306 patients (94.15%). Statistically significant differences were found in tetanus antibody levels in different age groups. Mean concentrations and the percentage of children with high tetanus antibody titers increased with age. No similar correlation was found for diphtheria antibodies. High diphtheria antibody levels co-occurred in 72% of the children with high tetanus antibody levels; 95% of the children with low tetanus antibody levels had low levels of diphtheria antibodies. The percentage of children with protective diphtheria antibody levels is lower than that in the case of tetanus antibodies, both in Poland and abroad, but the high proportion of children without diphtheria protection in Poland is an exception. This is all the more puzzling when taking into account that Polish children are administered a total of 5 doses containing a high concentration of diphtheria toxoid, at intervals shorter than 5 years. The decrease in antibody titers occurring over time is a significant factor in vaccination program planning. Tetanus antibody concentrations were found to be high, but responses to the diphtheria and tetanus components were divergent. The percentage of children protected against diphtheria was significantly lower than protected against tetanus. PMID:27930568

Does vaccination ensure protection? Assessing diphtheria and tetanus antibody levels in a population of healthy children: A cross-sectional study.

PubMed

Gowin, Ewelina; Wysocki, Jacek; Kałużna, Ewelina; Świątek-Kościelna, Bogna; Wysocka-Leszczyńska, Joanna; Michalak, Michał; Januszkiewicz-Lewandowska, Danuta

2016-12-01

Vaccination effectiveness is proven when the disease does not develop after a patient is exposed to the pathogen. In the case of rare diseases, vaccination effectiveness is assessed by monitoring specific antibody levels in the population. Such recurrent analyses allow the evaluation of vaccination programs. The primary schedule of diphtheria and tetanus vaccinations is similar in various countries, with differences mainly in the number and timing of booster doses. The aim of the study was to assess diphtheria and tetanus antibody concentrations in a population of healthy children.Diphtheria and tetanus antibody levels were analyzed in a group of 324 children aged 18 to 180 months. All children were vaccinated in accordance with the Polish vaccination schedule.Specific antibody concentrations greater than 0.1 IU/mL were considered protective against tetanus or diphtheria. Levels above 1.0 were considered to ensure long-term protection.Protective levels of diphtheria antibodies were found in 229 patients (70.46%), and of tetanus in 306 patients (94.15%). Statistically significant differences were found in tetanus antibody levels in different age groups. Mean concentrations and the percentage of children with high tetanus antibody titers increased with age. No similar correlation was found for diphtheria antibodies. High diphtheria antibody levels co-occurred in 72% of the children with high tetanus antibody levels; 95% of the children with low tetanus antibody levels had low levels of diphtheria antibodies.The percentage of children with protective diphtheria antibody levels is lower than that in the case of tetanus antibodies, both in Poland and abroad, but the high proportion of children without diphtheria protection in Poland is an exception. This is all the more puzzling when taking into account that Polish children are administered a total of 5 doses containing a high concentration of diphtheria toxoid, at intervals shorter than 5 years. The decrease in antibody titers occurring over time is a significant factor in vaccination program planning.Tetanus antibody concentrations were found to be high, but responses to the diphtheria and tetanus components were divergent. The percentage of children protected against diphtheria was significantly lower than protected against tetanus.

Accurate predictions of population-level changes in sequence and structural properties of HIV-1 Env using a volatility-controlled diffusion model

PubMed Central

DeLeon, Orlando; Hodis, Hagit; O’Malley, Yunxia; Johnson, Jacklyn; Salimi, Hamid; Zhai, Yinjie; Winter, Elizabeth; Remec, Claire; Eichelberger, Noah; Van Cleave, Brandon; Puliadi, Ramya; Harrington, Robert D.; Stapleton, Jack T.; Haim, Hillel

2017-01-01

The envelope glycoproteins (Envs) of HIV-1 continuously evolve in the host by random mutations and recombination events. The resulting diversity of Env variants circulating in the population and their continuing diversification process limit the efficacy of AIDS vaccines. We examined the historic changes in Env sequence and structural features (measured by integrity of epitopes on the Env trimer) in a geographically defined population in the United States. As expected, many Env features were relatively conserved during the 1980s. From this state, some features diversified whereas others remained conserved across the years. We sought to identify “clues” to predict the observed historic diversification patterns. Comparison of viruses that cocirculate in patients at any given time revealed that each feature of Env (sequence or structural) exists at a defined level of variance. The in-host variance of each feature is highly conserved among individuals but can vary between different HIV-1 clades. We designate this property “volatility” and apply it to model evolution of features as a linear diffusion process that progresses with increasing genetic distance. Volatilities of different features are highly correlated with their divergence in longitudinally monitored patients. Volatilities of features also correlate highly with their population-level diversification. Using volatility indices measured from a small number of patient samples, we accurately predict the population diversity that developed for each feature over the course of 30 years. Amino acid variants that evolved at key antigenic sites are also predicted well. Therefore, small “fluctuations” in feature values measured in isolated patient samples accurately describe their potential for population-level diversification. These tools will likely contribute to the design of population-targeted AIDS vaccines by effectively capturing the diversity of currently circulating strains and addressing properties of variants expected to appear in the future. PMID:28384158

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kastner, S.O.; Bhatia, A.K.

A generalized method for obtaining individual level population ratios is used to obtain relative intensities of extreme ultraviolet Fe XV emission lines in the range 284 --500 A, which are density dependent for electron densities in the tokamak regime or higher. Four lines in particular are found to attain quite high intensities in the high-density limit. The same calculation provides inelastic contributions to linewidths. The method connects level populations and level widths through total probabilities t/sub i/j, related to ''taboo'' probabilities of Markov chain theory. The t/sub i/j are here evaluated for a real atomic system, being therefore of potentialmore » interest to random-walk theorists who have been limited to idealized systems characterized by simplified transition schemes.« less

Impact of selective logging on inbreeding and gene dispersal in an Amazonian tree population of Carapa guianensis Aubl.

PubMed

Cloutier, D; Kanashiro, M; Ciampi, A Y; Schoen, D J

2007-02-01

Selective logging may impact patterns of genetic diversity within populations of harvested forest tree species by increasing distances separating conspecific trees, and modifying physical and biotic features of the forest habitat. We measured levels of gene diversity, inbreeding, pollen dispersal and spatial genetic structure (SGS) of an Amazonian insect-pollinated Carapa guianensis population before and after commercial selective logging. Similar levels of gene diversity and allelic richness were found before and after logging in both the adult and the seed generations. Pre- and post-harvest outcrossing rates were high, and not significantly different from one another. We found no significant levels of biparental inbreeding either before or after logging. Low levels of pollen pool differentiation were found, and the pre- vs. post-harvest difference was not significant. Pollen dispersal distance estimates averaged between 75 m and 265 m before logging, and between 76 m and 268 m after logging, depending on the value of tree density and the dispersal model used. There were weak and similar levels of differentiation of allele frequencies in the adults and in the pollen pool, before and after logging occurred, as well as weak and similar pre- and post-harvest levels of SGS among adult trees. The large neighbourhood sizes estimated suggest high historical levels of gene flow. Overall our results indicate that there is no clear short-term genetic impact of selective logging on this population of C. guianensis.

L-type calcium channels refine the neural population code of sound level.

PubMed

Grimsley, Calum Alex; Green, David Brian; Sivaramakrishnan, Shobhana

2016-12-01

The coding of sound level by ensembles of neurons improves the accuracy with which listeners identify how loud a sound is. In the auditory system, the rate at which neurons fire in response to changes in sound level is shaped by local networks. Voltage-gated conductances alter local output by regulating neuronal firing, but their role in modulating responses to sound level is unclear. We tested the effects of L-type calcium channels (Ca L : Ca V 1.1-1.4) on sound-level coding in the central nucleus of the inferior colliculus (ICC) in the auditory midbrain. We characterized the contribution of Ca L to the total calcium current in brain slices and then examined its effects on rate-level functions (RLFs) in vivo using single-unit recordings in awake mice. Ca L is a high-threshold current and comprises ∼50% of the total calcium current in ICC neurons. In vivo, Ca L activates at sound levels that evoke high firing rates. In RLFs that increase monotonically with sound level, Ca L boosts spike rates at high sound levels and increases the maximum firing rate achieved. In different populations of RLFs that change nonmonotonically with sound level, Ca L either suppresses or enhances firing at sound levels that evoke maximum firing. Ca L multiplies the gain of monotonic RLFs with dynamic range and divides the gain of nonmonotonic RLFs with the width of the RLF. These results suggest that a single broad class of calcium channels activates enhancing and suppressing local circuits to regulate the sensitivity of neuronal populations to sound level. Copyright © 2016 the American Physiological Society.

The role of parasite-driven selection in shaping landscape genomic structure in red grouse (Lagopus lagopus scotica).

PubMed

Wenzel, Marius A; Douglas, Alex; James, Marianne C; Redpath, Steve M; Piertney, Stuart B

2016-01-01

Landscape genomics promises to provide novel insights into how neutral and adaptive processes shape genome-wide variation within and among populations. However, there has been little emphasis on examining whether individual-based phenotype-genotype relationships derived from approaches such as genome-wide association (GWAS) manifest themselves as a population-level signature of selection in a landscape context. The two may prove irreconcilable as individual-level patterns become diluted by high levels of gene flow and complex phenotypic or environmental heterogeneity. We illustrate this issue with a case study that examines the role of the highly prevalent gastrointestinal nematode Trichostrongylus tenuis in shaping genomic signatures of selection in red grouse (Lagopus lagopus scotica). Individual-level GWAS involving 384 SNPs has previously identified five SNPs that explain variation in T. tenuis burden. Here, we examine whether these same SNPs display population-level relationships between T. tenuis burden and genetic structure across a small-scale landscape of 21 sites with heterogeneous parasite pressure. Moreover, we identify adaptive SNPs showing signatures of directional selection using F(ST) outlier analysis and relate population- and individual-level patterns of multilocus neutral and adaptive genetic structure to T. tenuis burden. The five candidate SNPs for parasite-driven selection were neither associated with T. tenuis burden on a population level, nor under directional selection. Similarly, there was no evidence of parasite-driven selection in SNPs identified as candidates for directional selection. We discuss these results in the context of red grouse ecology and highlight the broader consequences for the utility of landscape genomics approaches for identifying signatures of selection. © 2015 John Wiley & Sons Ltd.

Vibrational population of the A super 3 sigma sub u/+/ and B super 3 pi sub g states of N2 in normal auroras.

NASA Technical Reports Server (NTRS)

Cartwright, D. C.; Trajmar, S.; Williams, W.

1971-01-01

Use of new electron impact excitation cross sections for the six lowest triplet states (A, B, W, C, E, D) of N2, and solution of the coupled equations of statistical equilibrium to obtain the vibrational population of each electronic state. The results show that cascade from high levels of the A super 3 sigma sub u(+) state and from the W super 3 delta sub u state is significant in populating the lower vibrational levels of the B state and hence the character of its ?apparent' excitation cross sections. For the B state excited under auroral conditions, the fraction of the total population due to cascade processes exceeds 25% for all levels lower than 7 and is greater than 80% for B(v' = 0). For the A state under similar conditions, cascade from the B state contributes 50% or more of the total vibrational population for levels lower than 7, and 80% or more for levels below 4. For levels of the A state greater than 7, the A yields B transitions depopulate the levels rapidly and indicate that the Vegard-Kaplan emissions from these higher levels will be weak or totally absent in normal auroras.

The Effects of Soil Type, Particle Size, Temperature, and Moisture on Reproduction of Belonolaimus longicaudatus.

PubMed

Robbins, R T; Barker, K R

1974-01-01

Effects of soil type, particle size, temperature, and moisture on the reproduction of Belonolaimus longicaudatus were investigated under greenhouse conditions. Nematode increases occurred only in soils with a minimum of 80% sand and a maximum of 10% clay. Optimum soil particle size for reproduction of the Tarboro, N.C. and Tifton, Ga. populations of the nematode was near that of 120-370 mum (65-mesh) silica sand. Reproduction was greatest at 25-30 C. Some reproduction by the Tifton, Ga. population occurred at 35 C, whereas the Tarboro, N.C. population declined, as compared to the initial inoculum. Both populations reproduced slightly at 20 C. Nematode reproduction was greater at a moisture level of 7% than at a high of 30% or a low of 2%. Reproduction occurred at the high moisture level only when the nutrient solution was aerated.

Intraspecific variation in cellular and biochemical heat response strategies of Mediterranean Xeropicta derbentina [Pulmonata, Hygromiidae].

PubMed

Troschinski, Sandra; Di Lellis, Maddalena A; Sereda, Sergej; Hauffe, Torsten; Wilke, Thomas; Triebskorn, Rita; Köhler, Heinz-R

2014-01-01

Dry and hot environments challenge the survival of terrestrial snails. To minimize overheating and desiccation, physiological and biochemical adaptations are of high importance for these animals. In the present study, seven populations of the Mediterranean land snail species Xeropicta derbentina were sampled from their natural habitat in order to investigate the intraspecific variation of cellular and biochemical mechanisms, which are assigned to contribute to heat resistance. Furthermore, we tested whether genetic parameters are correlated with these physiological heat stress response patterns. Specimens of each population were individually exposed to elevated temperatures (25 to 52°C) for 8 h in the laboratory. After exposure, the health condition of the snails' hepatopancreas was examined by means of qualitative description and semi-quantitative assessment of histopathological effects. In addition, the heat-shock protein 70 level (Hsp70) was determined. Generally, calcium cells of the hepatopancreas were more heat resistant than digestive cells - this phenomenon was associated with elevated Hsp70 levels at 40°C.We observed considerable variation in the snails' heat response strategy: Individuals from three populations invested much energy in producing a highly elevated Hsp70 level, whereas three other populations invested energy in moderate stress protein levels - both strategies were in association with cellular functionality. Furthermore, one population kept cellular condition stable despite a low Hsp70 level until 40°C exposure, whereas prominent cellular reactions were observed above this thermal limit. Genetic diversity (mitochondrial cytochrome c oxidase subunit I gene) within populations was low. Nevertheless, when using genetic indices as explanatory variables in a multivariate regression tree (MRT) analysis, population structure explained mean differences in cellular and biochemical heat stress responses, especially in the group exposed to 40°C. Our study showed that, even in similar habitats within a close range, populations of the same species use different stress response strategies that all rendered survival possible.

Intraspecific Variation in Cellular and Biochemical Heat Response Strategies of Mediterranean Xeropicta derbentina [Pulmonata, Hygromiidae

PubMed Central

Troschinski, Sandra; Di Lellis, Maddalena A.; Sereda, Sergej; Hauffe, Torsten; Wilke, Thomas; Triebskorn, Rita; Köhler, Heinz-R.

2014-01-01

Dry and hot environments challenge the survival of terrestrial snails. To minimize overheating and desiccation, physiological and biochemical adaptations are of high importance for these animals. In the present study, seven populations of the Mediterranean land snail species Xeropicta derbentina were sampled from their natural habitat in order to investigate the intraspecific variation of cellular and biochemical mechanisms, which are assigned to contribute to heat resistance. Furthermore, we tested whether genetic parameters are correlated with these physiological heat stress response patterns. Specimens of each population were individually exposed to elevated temperatures (25 to 52°C) for 8 h in the laboratory. After exposure, the health condition of the snails' hepatopancreas was examined by means of qualitative description and semi-quantitative assessment of histopathological effects. In addition, the heat-shock protein 70 level (Hsp70) was determined. Generally, calcium cells of the hepatopancreas were more heat resistant than digestive cells - this phenomenon was associated with elevated Hsp70 levels at 40°C.We observed considerable variation in the snails' heat response strategy: Individuals from three populations invested much energy in producing a highly elevated Hsp70 level, whereas three other populations invested energy in moderate stress protein levels - both strategies were in association with cellular functionality. Furthermore, one population kept cellular condition stable despite a low Hsp70 level until 40°C exposure, whereas prominent cellular reactions were observed above this thermal limit. Genetic diversity (mitochondrial cytochrome c oxidase subunit I gene) within populations was low. Nevertheless, when using genetic indices as explanatory variables in a multivariate regression tree (MRT) analysis, population structure explained mean differences in cellular and biochemical heat stress responses, especially in the group exposed to 40°C. Our study showed that, even in similar habitats within a close range, populations of the same species use different stress response strategies that all rendered survival possible. PMID:24475158

Summary of regional response to the fourth inquiry.

PubMed

1979-01-01

Most of the governments that have responded to the 4th United Nations Population Growth Inquiry consider that the current rates of population growth are constraining the achievement of objectives of social economic development, and thus are unsatisfactory. The view of the governments of Iran, Pakistan, the Republic of Korea and Sri Lanka is that their current rates of growth constrain all aspects of development. The governments of Japan, Malaysia, and Singapore regard their current rates of growth as satisfactory and contributing to different aspects of economic and social development. As for mortality, most governments in the ESCAP region consider the current level of average life expectancy at birth acceptable, but present levels are unacceptable to the governments of Bangladesh, India, Iran, Nepal, Samoa and Thailand. Most governments consider their current levels of fertility to be too high and that they constrain the family well being, but the governments of Japan and Singapore believe that their fertility has contributed to the family well being. Additional attention in the inquiry was directed to obtaining information on the promotion of knowledge and policies (data collection and analysis; research; management, training, education and information; and development and evaluation of population policies). 10 governments have established a high level unit to deal with population policies, and 10 governments have indicated that they have integrated population measures and programs into comprehensive social and economic plans and programs.

Psilocybin impairs high-level but not low-level motion perception.

PubMed

Carter, Olivia L; Pettigrew, John D; Burr, David C; Alais, David; Hasler, Felix; Vollenweider, Franz X

2004-08-26

The hallucinogenic serotonin(1A&2A) agonist psilocybin is known for its ability to induce illusions of motion in otherwise stationary objects or textured surfaces. This study investigated the effect of psilocybin on local and global motion processing in nine human volunteers. Using a forced choice direction of motion discrimination task we show that psilocybin selectively impairs coherence sensitivity for random dot patterns, likely mediated by high-level global motion detectors, but not contrast sensitivity for drifting gratings, believed to be mediated by low-level detectors. These results are in line with those observed within schizophrenic populations and are discussed in respect to the proposition that psilocybin may provide a model to investigate clinical psychosis and the pharmacological underpinnings of visual perception in normal populations.

Transportation noise and exposed population of an urban area in the Republic of Korea.

PubMed

Ko, Joon Hee; Chang, Seo Il; Kim, Minho; Holt, James B; Seong, Jeong C

2011-02-01

Using noise prediction models, we explored the transportation noise levels of Youngdeungpo-gu, an urbanized area of Seoul Metropolitan City in the Republic of Korea. In addition, we estimated the population exposed to transportation noise levels and determined how many people are vulnerable to noise levels that would cause serious annoyance and sleep disturbance. Compared with the World Health Organization [WHO] recommended levels, the daytime and nighttime transportation noise levels were still high enough to have the two psychosocial effects on people when considering the recommended levels of the World Health Organization (WHO; 55 decibels [dB[A

Cellular Sentinels Toxicity Platform

DTIC Science & Technology

2017-02-01

Air Force Research Laboratory 711th Human Performance Wing U.S. Air Force School of Aerospace Medicine Aeromedical Research Department 2510 Fifth St...toxicity testing is to assess the likely risks posed to human populations at ambient exposure levels. Unfortunately, current approaches to toxicology... human populations at ambient exposure levels. For the past 50 years, this goal has been met by high dose testing in experimental animals with

Genetic diversity and sex ratio of naked mole rat, Heterocephalus glaber, zoo populations.

PubMed

Chau, Linh M; Groh, Amy M; Anderson, Emily C; Alcala, Micaela O; Mendelson, Joseph R; Slade, Stephanie B; Kerns, Kenton; Sarro, Steve; Lusardi, Clinton; Goodisman, Michael A D

2018-05-01

The naked mole rat, Heterocephalus glaber, is a highly unusual mammal that displays a complex social system similar to that found in eusocial insects. Colonies of H. glaber are commonly maintained in zoo collections because they represent fascinating educational exhibits for the public. However, little is known about the genetic structure or sex ratio of captive populations of H. glaber. In this study, we developed a set of microsatellite markers to examine genetic variation in three captive zoo populations of H. glaber. We also studied sex ratio of these captive populations. Our goal was to determine levels of genetic variation within, and genetic differences between, captive populations of H. glaber. Overall, we found modest levels of genetic variation in zoo populations. We also uncovered little evidence for inbreeding within the captive populations. However, zoo populations did differ genetically, which may reflect the isolation of captive naked mole rat colonies. Finally, we found no evidence of biased sex ratios within colonies. Overall, our study documents levels of genetic variation and sex ratios in a captive eusocial mammalian population. Our results may provide insight into how to manage captive populations of H. glaber. © 2018 Wiley Periodicals, Inc.

Role of the APOB Gene Polymorphism (c.12669G>A, p. Gln4154Lys) in Coronary Artery Disease in the Indian Punjabi Population.

PubMed

Sharma, R; Mahajan, M; Singh, B; Singh, G; Singh, P

2011-12-01

High concentration of apolipoprotein B (apoB) is a risk factor for coronary artery disease (CAD). The association of the APOB gene polymorphism c.12669G>A, p.Gln4154Lys with the risk of CAD varies considerably in different populations. The present study represents the first investigation regarding the role of this APOB gene polymorphism with CAD in the Indian Punjabi population. We have studied the APOB gene polymorphism c.12669G>A, p.Gln4154Lys and its relationship with lipid, apoB, low-density lipoprotein (LDL) heterogeneity and oxidation in subjects suffering from CAD. The study was conducted on 87 patients with CAD; 75 healthy subjects served as controls. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to determine the DNA polymorphism in the APOB gene. Frequency of R- (mutant) allele was significantly high (p <0.05) in CAD patients when compared to controls. Variations in serum lipid levels in the R+R+ and R+R- APOB genotypes were insignificant (p >0.05). However, serum apoB levels were significantly raised (p <0.05) in CAD patients with the R+R- genotype as compared to those with the R+R+ APOB genotype. Coronary artery disease patients had raised significantly raised (p <0.01) Log triglyceride/high density lipoprotein-cholesterol (HDL-C) ratio, apoB carbonyl content and increased malondialdehyde-low density lipoprotein (MDA-LDL levels, irrespective of APOB genotype as compared to controls. Carriers of the R- allele are at higher risk of CAD, probably because of elevated serum apoB levels in the Indian Punjabi population. Overall, it may be concluded that the R- allele might be associated with increased susceptibility towards CAD development in the Indian Punjabi population, and one of the linking factor is the elevation in serum apoB levels. However, this association needs further evaluation in a larger population. Secondly, the robust mechanism behind the positive association of the R- allele with raised serum apoB levels needs to be explored, which might be helpful in the strengthening the observed results.

Septic tank additive impacts on microbial populations.

PubMed

Pradhan, S; Hoover, M T; Clark, G H; Gumpertz, M; Wollum, A G; Cobb, C; Strock, J

2008-01-01

Environmental health specialists, other onsite wastewater professionals, scientists, and homeowners have questioned the effectiveness of septic tank additives. This paper describes an independent, third-party, field scale, research study of the effects of three liquid bacterial septic tank additives and a control (no additive) on septic tank microbial populations. Microbial populations were measured quarterly in a field study for 12 months in 48 full-size, functioning septic tanks. Bacterial populations in the 48 septic tanks were statistically analyzed with a mixed linear model. Additive effects were assessed for three septic tank maintenance levels (low, intermediate, and high). Dunnett's t-test for tank bacteria (alpha = .05) indicated that none of the treatments were significantly different, overall, from the control at the statistical level tested. In addition, the additives had no significant effects on septic tank bacterial populations at any of the septic tank maintenance levels. Additional controlled, field-based research iswarranted, however, to address additional additives and experimental conditions.

Population density, socioeconomic environment and all-cause mortality: a multilevel survival analysis of 2.7 million individuals in Denmark.

PubMed

Meijer, Mathias; Kejs, Anne Mette; Stock, Christiane; Bloomfield, Kim; Ejstrud, Bo; Schlattmann, Peter

2012-03-01

This study examines the relative effects of population density and area-level SES on all-cause mortality in Denmark. A shared frailty model was fitted with 2.7 million persons aged 30-81 years in 2,121 parishes. Residence in areas with high population density increased all-cause mortality for all age groups. For older age groups, residence in areas with higher proportions of unemployed persons had an additional effect. Area-level factors explained considerably more variation in mortality among the elderly than among younger generations. Overall this study suggests that structural prevention efforts in neighborhoods could help reduce mortality when mediating processes between area-level socioeconomic status, population density and mortality are found. Copyright © 2011 Elsevier Ltd. All rights reserved.

Extensive genome-wide autozygosity in the population isolates of Daghestan.

PubMed

Karafet, Tatiana M; Bulayeva, Kazima B; Bulayev, Oleg A; Gurgenova, Farida; Omarova, Jamilia; Yepiskoposyan, Levon; Savina, Olga V; Veeramah, Krishna R; Hammer, Michael F

2015-10-01

Isolated populations are valuable resources for mapping disease genes, as inbreeding increases genome-wide homozygosity and enhances the ability to map disease alleles on a genetically uniform background within a relatively homogenous environment. The populations of Daghestan are thought to have resided in the Caucasus Mountains for hundreds of generations and are characterized by a high prevalence of certain complex diseases. To explore the extent to which their unique population history led to increased levels of inbreeding, we genotyped >550 000 autosomal single-nucleotide polymorphisms (SNPs) in a set of 14 population isolates speaking Nakh-Daghestanian (ND) languages. The ND-speaking populations showed greatly elevated coefficients of inbreeding, very high numbers and long lengths of Runs of Homozygosity, and elevated linkage disequilibrium compared with surrounding groups from the Caucasus, the Near East, Europe, Central and South Asia. These results are consistent with the hypothesis that most ND-speaking groups descend from a common ancestral population that fragmented into a series of genetic isolates in the Daghestanian highlands. They have subsequently maintained a long-term small effective population size as a result of constant inbreeding and very low levels of gene flow. Given these findings, Daghestanian population isolates are likely to be useful for mapping genes associated with complex diseases.

The decrease in the population of Gluconacetobacter diazotrophicus in sugarcane after nitrogen fertilization is related to plant physiology in split root experiments.

PubMed

Rodríguez-Andrade, Osvaldo; Fuentes-Ramírez, Luis E; Morales-García, Yolanda E; Molina-Romero, Dalia; Bustillos-Cristales, María R; Martínez-Contreras, Rebeca D; Muñoz-Rojas, Jesús

2015-01-01

It has been established that a decrease in the population of Gluconacetobacter diazotrophicus associated with sugarcane occurs after nitrogen fertilization. This fact could be due to a direct influence of NH(4)NO(3) on bacterial cells or to changes in plant physiology after fertilizer addition, affecting bacterial establishment. In this work, we observed that survival of G. diazotrophicus was directly influenced when 44.8mM of NH(4)NO(3) (640mgN/plant) was used for in vitro experiments. Furthermore, micropropagated sugarcane plantlets were inoculated with G. diazotrophicus and used for split root experiments, in which both ends of the system were fertilized with a basal level of NH(4)NO(3) (0.35mM; 10mgN/plant). Twenty days post inoculation (dpi) one half of the plants were fertilized with a high dose of NH(4)NO(3) (6.3mM; 180 mgN/plant) on one end of the system. This nitrogen level was lower than that directly affecting G. diazotrophicus cells; however, it caused a decrease in the bacterial population in comparison with control plants fertilized with basal nitrogen levels. The decrease in the population of G. diazotrophicus was higher in pots fertilized with a basal nitrogen level when compared with the corresponding end supplied with high levels of NH4NO3 (100dpi; 80 days post fertilization) of the same plant system. These observations suggest that the high nitrogen level added to the plants induce systemic physiological changes that affect the establishment of G. diazotrophicus. Copyright © 2015 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Genetic differentiation in red-bellied piranha populations (Pygocentrus nattereri, Kner, 1858) from the Solimões-Amazonas River.

PubMed

Dos Santos, Carlos Henrique Dos A; de Sá Leitão, Carolina S; Paula-Silva, Maria de N; Almeida-Val, Vera Maria F

2016-06-01

Red-bellied piranhas (Pygocentrus nattereri) are widely caught with different intensities throughout the region of Solimões-Amazonas River by local fishermen. Thus, the management of this resource is performed in the absence of any information on its genetic stock. P. nattereri is a voracious predator and widely distributed in the Neotropical region, and it is found in other regions of American continent. However, information about genetic variability and structure of wild populations of red-bellied piranha is unavailable. Here, we describe the levels of genetic diversity and genetic structure of red-bellied piranha populations collected at different locations of Solimões-Amazonas River system. We collected 234 red-bellied piranhas and analyzed throughout eight microsatellite markers. We identified high genetic diversity within populations, although the populations of lakes ANA, ARA, and MAR have shown some decrease in their genetic variability, indicating overfishing at these communities. Was identified the existence of two biological populations when the analysis was taken altogether at the lakes of Solimões-Amazonas River system, with significant genetic differentiation between them. The red-bellied piranha populations presented limited gene flow between two groups of populations, which were explained by geographical distance between these lakes. However, high level of gene flow was observed between the lakes within of the biological populations. We have identified high divergence between the Catalão subpopulation and all other subpopulations. We suggest the creation of sustainable reserve for lakes near the city of Manaus to better manage and protect this species, whose populations suffer from both extractive and sport fishing.

Genetic diversity and structure in two species of Leavenworthia with self-incompatible and self-compatible populations

PubMed Central

Koelling, V A; Hamrick, J L; Mauricio, R

2011-01-01

Self-fertilization is a common mating system in plants and is known to reduce genetic diversity, increase genetic structure and potentially put populations at greater risk of extinction. In this study, we measured the genetic diversity and structure of two cedar glade endemic species, Leavenworthia alabamica and L. crassa. These species have self-incompatible (SI) and self-compatible (SC) populations and are therefore ideal for understanding how the mating system affects genetic diversity and structure. We found that L. alabamica and L. crassa had high species-level genetic diversity (He=0.229 and 0.183, respectively) and high genetic structure among their populations (FST=0.45 and 0.36, respectively), but that mean genetic diversity was significantly lower in SC compared with SI populations (SC vs SI, He for L. alabamica was 0.065 vs 0.206 and for L. crassa was 0.084 vs 0.189). We also found significant genetic structure using maximum-likelihood clustering methods. These data indicate that the loss of SI leads to the loss of genetic diversity within populations. In addition, we examined genetic distance relationships between SI and SC populations to analyze possible population history and origins of self-compatibility. We find there may have been multiple origins of self-compatibility in L. alabamica and L. crassa. However, further work is required to test this hypothesis. Finally, given their high genetic structure and that individual populations harbor unique alleles, conservation strategies seeking to maximize species-level genetic diversity for these or similar species should protect multiple populations. PMID:20485327

Practising pastoralism in an agricultural environment: An isotopic analysis of the impact of the Hunnic incursions on Pannonian populations

PubMed Central

Evans, Jane; Chapman, Hazel; Fóthi, Erzsébet

2017-01-01

We conducted a multi-isotope study of five fifth-century AD cemeteries in modern-day Hungary to determine relationships between nomadic-pastoralist incomers—the historically documented Huns and other nomadic groups—and the sedentary agricultural population of the late Roman province of Pannonia. Contemporary historical sources describe this relationship as adversarial and destructive for the late Roman population, but archaeological evidence indicates high levels of hybridity between different groups. We undertook carbon, nitrogen, strontium and oxygen isotope analyses of bone collagen, dentine and tooth enamel at Keszthely-Fenékpuszta, Hács-Béndekpuszta, Győr-Széchenyi Square, Mözs and Szolnok-Szanda to examine these relationships through past subsistence practices. The patterns at all sites indicate medium to high animal protein consumption with little evidence for a significant contribution of aquatic resources. All populations relied to a great extent on C4 plants, most likely millet. Within each population, diet was heterogeneous, with significant variations in terms of animal protein and C3 and C4 plant consumption. High levels of intra-population and individual variability suggest that populations made use of a range of subsistence strategies, with many individuals exhibiting significant changes over their lifetimes. Rather than being characterised only by violence, the historically-documented influx of nomadic populations appears to have led to widespread changes in subsistence strategies of populations in the Carpathian basin. Nomadic-pastoralist groups may have switched to smaller herds and more farming, and, conversely, local populations may have integrated with a new economic system based on animal herding. PMID:28328951

Animal source food intake and association with blood cholesterol, glycerophospholipids and sphingolipids in a northern Swedish population.

PubMed

Igl, Wilmar; Kamal-Eldin, Afaf; Johansson, Asa; Liebisch, Gerhard; Gnewuch, Carsten; Schmitz, Gerd; Gyllensten, Ulf

2013-01-01

The high intake of game meat in populations with a subsistence-based diet may affect their blood lipids and health status. To examine the association between diet and circulating levels of blood lipid levels in a northern Swedish population. We compared a group with traditional lifestyle (TLS) based on reindeer herding (TLS group) with those from the same area with a non-traditional lifestyle (NTLS) typical of more industrialized regions of Sweden (NTLS group). The analysis was based on self-reported intake of animal source food (i.e. non-game meat, game meat, fish, dairy products and eggs) and the serum blood level of a number of lipids [total cholesterol (TC), low-density lipoprotein cholesterol (LDL), high-density lipoprotein cholesterol (HDL), triglycerides (TG), glycerophospholipids and sphingolipids]. The TLS group had higher cholesterol, LDL and HDL levels than the reference group. Of the TLS group, 65% had cholesterol levels above the threshold for increased risk of coronary heart disease (≥ 240 mg/dl), as compared to 38% of the NTLS group. Self-reported consumption of game meat was positively associated with TC and LDL. The high game meat consumption of the TLS group is associated with increased cholesterol levels. High intake of animal protein and fat and low fibre is known to increase the risk of cardiovascular disease, but other studies of the TLS in northern Sweden have shown comparable incidences of cardiovascular disease to the reference (NTLS) group from the same geographical area. This indicates that factors other than TC influence disease risk. One such possible factor is dietary phospholipids, which are also found in high amounts specifically in game meat and have been shown to inhibit cholesterol absorption.

Impacts of nutrients and related environmental factors on distribution and size structure of Noctiluca scintillans populations of the eutrophic Tha Chin estuary, Thailand.

PubMed

Chuenniyom, Wansiri; Meksumpun, Charumas; Meksumpun, Shettapong

2012-01-01

This study aimed to analyze the impacts of nutrients and related aquatic factors on changes in the Noctiluca population of the Tha Chin estuary, a nutrient-rich estuary located in the inner Gulf of Thailand. Field surveys were carried out at 30 stations during November 2009 to August 2010. The results indicated high levels of dissolved inorganic nitrogen (DIN; 13.89-46.99 μmol/L) and PO(4)(3-)-P (0.20-3.05 μmol/L) where the Noctiluca red tide occurred, particularly during the high-loading period. Dense populations were usually found in the outer part of the estuary with comparatively high salinity (25-29 psu). The highest Noctiluca density was 72,333 cells L(-1) and the cell diameters ranged between 360 and 460 μm. Proportions of small-sized cells (P(s); less than 300 μm) varied over time. In this study, P(s) showed a positive correlation with levels of PO(4)(3-)-P, while the total population density was significantly affected by levels of NH(4)(+)-N and DIN (p < 0.05). Overall, PO(4)(3-)-P influenced the development of the Noctiluca red tide, with the limitation of PO(4)(3-)-P levels to below 1 μmol/L suggested for controlling Noctiluca red tide outbreaks at their origin. To support environmental conservation and maintain sustainable production in the estuary, the levels of PO(4)(3-)-P should be considered for the further effective development of water quality standards in estuarine zones.

Stress in police officers: a study of the origins, prevalence and severity of stress-related symptoms within a county police force.

PubMed

Collins, P A; Gibbs, A C C

2003-06-01

High levels of stress-related illness are causing concern across industry. Against a background of impending legislative moves to try to improve this situation, there is a need to identify key work-related stressors. Police work tends to be regarded as inherently stressful because of the personal risk of exposure to confrontation and violence and the day-to-day involvement in a variety of traumatic incidents. As a result, high levels of stress-related symptoms might be expected in this population. To examine the sources of stress-related symptoms within police officers and measure the prevalence of significant associated mental ill-health. A cross-sectional questionnaire survey of a population of 1206 police officers was performed to assess levels of strain associated with a series of potential home and work related stressors. Participants were then split into low and high scoring groups on the basis of a General Health Questionnaire (GHQ) threshold score in order to identify those stressors most associated with mental ill-health effects. Occupational stressors ranking most highly within the population were not specific to policing, but to organizational issues such as the demands of work impinging upon home life, lack of consultation and communication, lack of control over workload, inadequate support and excess workload in general. The high scoring group constituted 41% of the population and differed significantly from those with low scores in perception of all stressors, ranking both personal and occupational stressors more highly, and from personality constraints appeared significantly more 'stress-prone'. A significant association between gender and mental ill-health was found, with females more likely to score more highly on the GHQ than males. This study confirms previous findings of organizational culture and workload as the key issues in officer stress. Given that the degree of symptomatology appears to be worsening, management action is required. Further research is indicated within the police population into a possible increased susceptibility in female officers.

Are higher blood mercury levels associated with dry eye symptoms in adult Koreans? A population-based cross-sectional study.

PubMed

Chung, So-Hyang; Myong, Jun-Pyo

2016-04-27

The purpose of this study was to investigate whether blood mercury concentrations associated with the presence of dry eye symptoms in a nationally representative Korean population. Population-based prospective cross-sectional study using the heavy metal data set of the 2010-2012 Korean National Health and Nutrition Examination Survey (KNHANES). A total of 4761 adult Koreans were the eligible population in this study. Of the 7162 survey participants, 2401 were excluded because they were <19 years of age, there were missing data in the heavy metal data set, or they had diabetes, rheumatoid arthritis, thyroid disease, asthma, depression and/or under-the-eye surgery. Blood mercury levels were measured on the day the participants completed a questionnaire regarding the presence of dry eye symptoms (persistent dryness or eye irritation). The population was divided into low and high groups by median level (4.26 and 2.89 µg/L for males and females, respectively). Self-reported dry eye symptoms were present in 13.0% of the cohort. Participants with dry eye symptoms were significantly more likely to have blood mercury levels exceeding the median than those without dry eye symptoms (45.7% vs 51.7%, p=0.021). Logistic regression analysis showed that, after adjusting for age, gender, education, total household income, smoking status, heavy alcohol use, sleep time, perceived stress status, total cholesterol levels and atopy history, dry eye symptoms were significantly associated with blood mercury levels that exceeded the median (reference: lower mercury group; OR, 1.324; 95% CI 1.059 to 1.655; p<0.05). High blood mercury levels were associated with dry eye symptoms in a nationally representative Korean population. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Exploring the multidimensionality of stature variation in the past through comparisons of archaeological and living populations.

PubMed

Vercellotti, Giuseppe; Piperata, Barbara A; Agnew, Amanda M; Wilson, Warren M; Dufour, Darna L; Reina, Julio C; Boano, Rosa; Justus, Hedy M; Larsen, Clark Spencer; Stout, Sam D; Sciulli, Paul W

2014-10-01

Adult stature variation is commonly attributed to differential stress-levels during development. However, due to selective mortality and heterogeneous frailty, a population's tall stature may be more indicative of high selective pressures than of positive life conditions. This article examines stature in a biocultural context and draws parallels between bioarchaeological and living populations to explore the multidimensionality of stature variation in the past. This study investigates: 1) stature differences between archaeological populations exposed to low or high stress (inferred from skeletal indicators); 2) similarities in growth retardation patterns between archaeological and living groups; and 3) the apportionment of variance in growth outcomes at the regional level in archaeological and living populations. Anatomical stature estimates were examined in relation to skeletal stress indicators (cribra orbitalia, porotic hyperostosis, linear enamel hypoplasia) in two medieval bioarchaeological populations. Stature and biocultural information were gathered for comparative living samples from South America. Results indicate 1) significant (P < 0.01) differences in stature between groups exposed to different levels of skeletal stress; 2) greater prevalence of stunting among living groups, with similar patterns in socially stratified archaeological and modern groups; and 3) a degree of regional variance in growth outcomes consistent with that observed for highly selected traits. The relationship between early stress and growth is confounded by several factors-including catch-up growth, cultural buffering, and social inequality. The interpretations of early life conditions based on the relationship between stress and stature should be advanced with caution. Copyright © 2014 Wiley Periodicals, Inc.

Prevalence of obesity in a rural Asian Indian (Bangladeshi) population and its determinants.

PubMed

Siddiquee, Tasnima; Bhowmik, Bishwajit; Da Vale Moreira, Nayla Cristina; Mujumder, Anindita; Mahtab, Hajera; Khan, A K Azad; Hussain, Akhtar

2015-09-04

Obesity has reached epidemic proportions worldwide including Bangladesh. To assess the prevalence and associated factors of general and central obesity in a rural Bangladeshi population based on newly proposed cut off level for Asian population. 2293 subjects aged ≥ 20 years from rural Bangladesh were randomly recruited to participate in a population-based, cross sectional survey, conducted in 2009. Both socio-demographic and anthropometric measurements were recorded. Age adjusted data for anthropometric indices were examined. The age standardized prevalence of overweight (BMI 23-24.9 kg/m(2)) and obesity (BMI ≥ 25 kg/m(2)) were 17.7 (95% confidence interval (CI): 16.1, 19.2%) and 26.2% (95% CI: 24.4, 27.9%), respectively. The age standardized prevalence of central obesity based on WC (M ≥ 90 & F ≥ 80 cm) and WHR (M ≥ 0.90 & F ≥ 0.80) were 39.8% (95% CI: 37.9, 41.7%) and 71.6% (95% CI: 69.8, 73.4%) respectively. The result shows that prevalence of central obesity was more in female than male. Study shows middle age, medium and high socioeconomic status (SES), low education levels, physical inactivity, high consumption of carbohydrate, protein and fat, were significant risk indicators for general and central obesity. Smoking was shown as protective factor for both general and central obesity. In rural Bangladeshi population, the prevalence of both general and central obesity was high among both sexes with the use of newly proposed cut off points for Asian population. Gender, diet, physical activity, education levels and SES were associated with the increase prevalence of obesity.

Retail food safety risks for populations of different races, ethnicities, and income levels.

PubMed

Signs, Renata J; Darcey, Valerie L; Carney, Trish A; Evans, Alison A; Quinlan, Jennifer J

2011-10-01

Research has found that populations with low socioeconomic status (SES) and minority populations have greater access to small corner markets and less access to supermarkets than high-SES and Caucasian populations. This represents a significant difference in the farm-to-fork continuum that these populations experience. This research examined whether differential retail access to foods results in different food safety risks at the retail level for consumers with different demographics. U.S. Census Bureau census tracts with high African American, Asian, Hispanic, Caucasian, low-SES, and high-SES populations were identified in Philadelphia, PA. Approximately 60 retail food establishments were sampled in each census tract category from June 2008 to June 2010. Food samples collected at stores included milk, eggs, lunchmeat, sandwiches, and ready-to-eat (RTE) fresh fruit, greens, and herbs, when available. With the exception of milk and eggs, only food that had been handled and/or prepared at the retail level was sampled. Food samples were tested for temperature, aerobic plate count, coliforms, fecal coliforms, Escherichia coli, Staphylococcus aureus, and Listeria monocytogenes. The results indicated that internal egg temperatures were higher in samples from low-SES census tracts than in eggs from Caucasian census tracts, and eggs were more often found unrefrigerated in markets in low-SES and Asian census tracts. Milk samples from markets in Hispanic and low-SES census tracts had higher aerobic plate counts than high-SES census tract samples. Sandwiches from markets in high-SES census tracts had higher coliform counts than sandwiches from markets in all other census tract categories. Markets in Asian census tracts had a higher incidence of fecal coliform contamination on sandwiches than markets in Caucasian census tracts. Fecal coliforms were present in a percentage of RTE greens from markets in all census tracts except African American, with the highest percentages of RTE greens positive for fecal coliforms in low-SES (100%), Asian (71.4%), and Caucasian (45.5%) markets.

Peanuts that keep aflatoxin at bay: a threshold that matters

USDA-ARS?s Scientific Manuscript database

High levels of aflatoxin in peanuts pose major health hazards for vulnerable populations of Sub-Saharan Africa (SSA) and South Asia. We used two independent approaches to generate peanuts that exhibit strong resistance to both A. flavus seed infection and aflatoxin production. A high level of geneti...

The Relationship Between Background Characteristics and Death Anxiety in Times of War: A Comparison Between Three Generations Arab and Jewish Families in Israel.

PubMed

Ron, Pnina

2016-11-01

(a) To compare the levels of death anxiety between the Jewish and Arab population in Israel after the Second Lebanon War and the Casting Lead Operation. (b) To compare the levels of death anxiety between three families' generations: elderly parents, their adult children and their adult grandchildren and (c) to learn about the relationship between background characteristics and death anxiety in times of war. The sample included 172 trios of elderly parents (ages 65 and up), their middle aged children (ages 41-64) and, their young adult children (ages 20-40) living at the northern and southern of Israel. Three quarters of the participants were Jews and the others were Arabs (including Muslims, Christians and Druze). Participants answered a self-report questioner. Death anxiety levels were measured by the Carmel and Mutran's instrument (1999). In general, the highest levels of death anxiety were found among the elderly parents (p < 0.01). Regarding the nationality and the gender variables, the highest levels of death anxiety were found among the adult Jewish daughters' group (p < 0.001). Nationality was found to be the most contributive variable for predicting death anxiety levels among the three generations; the sense of mastery was the second contributor, to predict death anxiety levels among the three generations' participants. Elderly population, Arab population and women, are at high risk to suffer from high levels of death anxiety in times of war in Israel. Special attention should be given to this population groups.

Linking resource selection and mortality modeling for population estimation of mountain lions in Montana

USGS Publications Warehouse

Robinson, Hugh S.; Ruth, Toni K.; Gude, Justin A.; Choate, David; DeSimone, Rich; Hebblewhite, Mark; Matchett, Marc R.; Mitchell, Michael S.; Murphy, Kerry; Williams, Jim

2015-01-01

To be most effective, the scale of wildlife management practices should match the range of a particular species’ movements. For this reason, combined with our inability to rigorously or regularly census mountain lion populations, several authors have suggested that mountain lions be managed in a source-sink or metapopulation framework. We used a combination of resource selection functions, mortality estimation, and dispersal modeling to estimate cougar population levels in Montana statewide and potential population level effects of planned harvest levels. Between 1980 and 2012, 236 independent mountain lions were collared and monitored for research in Montana. From these data we used 18,695 GPS locations collected during winter from 85 animals to develop a resource selection function (RSF), and 11,726 VHF and GPS locations from 142 animals along with the locations of 6343 mountain lions harvested from 1988–2011 to validate the RSF model. Our RSF model validated well in all portions of the State, although it appeared to perform better in Montana Fish, Wildlife and Parks (MFWP) Regions 1, 2, 4 and 6, than in Regions 3, 5, and 7. Our mean RSF based population estimate for the total population (kittens, juveniles, and adults) of mountain lions in Montana in 2005 was 3926, with almost 25% of the entire population in MFWP Region 1. Estimates based on a high and low reference population estimates produce a possible range of 2784 to 5156 mountain lions statewide. Based on a range of possible survival rates we estimated the mountain lion population in Montana to be stable to slightly increasing between 2005 and 2010 with lambda ranging from 0.999 (SD = 0.05) to 1.02 (SD = 0.03). We believe these population growth rates to be a conservative estimate of true population growth. Our model suggests that proposed changes to female harvest quotas for 2013–2015 will result in an annual statewide population decline of 3% and shows that, due to reduced dispersal, changes to harvest in one management unit may affect population growth in neighboring units where smaller or even no changes were made. Uncertainty regarding dispersal levels and initial population density may have a significant effect on predictions at a management unit scale (i.e. 2000 km2), while at a regional scale (i.e. 50,000 km2) large differences in initial population density result in relatively small changes in population growth rate, and uncertainty about dispersal may not be as influential. Doubling the presumed initial density from a low estimation of 2.19 total animals per 100 km2 resulted in a difference in annual population growth rate of only 2.6% statewide when compared to high density of 4.04 total animals per 100 km2 (low initial population estimate λ = 0.99, while high initial population estimate λ = 1.03). We suggest modeling tools such as this may be useful in harvest planning at a regional and statewide level.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhu Qin, E-mail: zhuqin@fudan.edu.cn; Peng Xizhe, E-mail: xzpeng@fudan.edu.cn

This study examines the impacts of population size, population structure, and consumption level on carbon emissions in China from 1978 to 2008. To this end, we expanded the stochastic impacts by regression on population, affluence, and technology model and used the ridge regression method, which overcomes the negative influences of multicollinearity among independent variables under acceptable bias. Results reveal that changes in consumption level and population structure were the major impact factors, not changes in population size. Consumption level and carbon emissions were highly correlated. In terms of population structure, urbanization, population age, and household size had distinct effects onmore » carbon emissions. Urbanization increased carbon emissions, while the effect of age acted primarily through the expansion of the labor force and consequent overall economic growth. Shrinking household size increased residential consumption, resulting in higher carbon emissions. Households, rather than individuals, are a more reasonable explanation for the demographic impact on carbon emissions. Potential social policies for low carbon development are also discussed. - Highlights: Black-Right-Pointing-Pointer We examine the impacts of population change on carbon emissions in China. Black-Right-Pointing-Pointer We expand the STIRPAT model by containing population structure factors in the model. Black-Right-Pointing-Pointer The population structure includes age structure, urbanization level, and household size. Black-Right-Pointing-Pointer The ridge regression method is used to estimate the model with multicollinearity. Black-Right-Pointing-Pointer The population structure plays a more important role compared with the population size.« less

The Genetic Structure and History of Africans and African Americans

PubMed Central

Tishkoff, Sarah A.; Reed, Floyd A.; Friedlaender, Françoise R.; Ehret, Christopher; Ranciaro, Alessia; Froment, Alain; Hirbo, Jibril B.; Awomoyi, Agnes A.; Bodo, Jean-Marie; Doumbo, Ogobara; Ibrahim, Muntaser; Juma, Abdalla T.; Kotze, Maritha J.; Lema, Godfrey; Moore, Jason H.; Mortensen, Holly; Nyambo, Thomas B.; Omar, Sabah A.; Powell, Kweli; Pretorius, Gideon S.; Smith, Michael W.; Thera, Mahamadou A.; Wambebe, Charles; Weber, James L.; Williams, Scott M.

2010-01-01

Africa is the source of all modern humans, but characterization of genetic variation and of relationships among populations across the continent has been enigmatic. We studied 121 African populations, four African American populations, and 60 non-African populations for patterns of variation at 1327 nuclear microsatellite and insertion/deletion markers. We identified 14 ancestral population clusters in Africa that correlate with self-described ethnicity and shared cultural and/or linguistic properties. We observed high levels of mixed ancestry in most populations, reflecting historical migration events across the continent. Our data also provide evidence for shared ancestry among geographically diverse hunter-gatherer populations (Khoesan speakers and Pygmies). The ancestry of African Americans is predominantly from Niger-Kordofanian (~71%), European (~13%), and other African (~8%) populations, although admixture levels varied considerably among individuals. This study helps tease apart the complex evolutionary history of Africans and African Americans, aiding both anthropological and genetic epidemiologic studies. PMID:19407144

Intraspecific divergence in sperm morphology of the green sea urchin, Strongylocentrotus droebachiensis: implications for selection in broadcast spawners

PubMed Central

2008-01-01

Background Sperm morphology can be highly variable among species, but less is known about patterns of population differentiation within species. Most studies of sperm morphometric variation are done in species with internal fertilization, where sexual selection can be mediated by complex mating behavior and the environment of the female reproductive tract. Far less is known about patterns of sperm evolution in broadcast spawners, where reproductive dynamics are largely carried out at the gametic level. We investigated variation in sperm morphology of a broadcast spawner, the green sea urchin (Strongylocentrotus droebachiensis), within and among spawnings of an individual, among individuals within a population, and among populations. We also examined population-level variation between two reproductive seasons for one population. We then compared among-population quantitative genetic divergence (QST) for sperm characters to divergence at neutral microsatellite markers (FST). Results All sperm traits except total length showed strong patterns of high diversity among populations, as did overall sperm morphology quantified using multivariate analysis. We also found significant differences in almost all traits among individuals in all populations. Head length, axoneme length, and total length had high within-male repeatability across multiple spawnings. Only sperm head width had significant within-population variation across two reproductive seasons. We found signatures of directional selection on head length and head width, with strong selection possibly acting on head length between the Pacific and West Atlantic populations. We also discuss the strengths and limitations of the QST-FST comparison. Conclusion Sperm morphology in S. droebachiensis is highly variable, both among populations and among individuals within populations, and has low variation within an individual across multiple spawnings. Selective pressures acting among populations may differ from those acting within, with directional selection implicated in driving divergence among populations and balancing selection as a possible mechanism for producing variability among males. Sexual selection in broadcast spawners may be mediated by different processes from those acting on internal fertilizers. Selective divergence in sperm head length among populations is associated with ecological differences among populations that may play a large role in mediating sexual selection in this broadcast spawner. PMID:18851755

[Genetic diversity and genetic structure of endangered wild Sinopodophyllum emodi by start codon targeted polymorphism].

PubMed

Chen, Da-Xia; Zhao, Ji-Feng; Liu, Xiang; Wang, Chang-Hua; Zhang, Zhi-Wei; Qin, Song-Yun; Zhong, Guo-Yue

2013-01-01

Revealed the genetic diversity level and genetic structure characteristics in Sinopodophyllum emodi, a rare and endangered species in China. We detected the genetic polymorphism within and among six wild populations (45 individuals) by the approach of Start Codon Targeted (SCoT) Polymorphism. The associated genetic parameters were calculated by POP-GENE1.31 and the relationship was constructed based on UPGMA method. A total of 350 bands were scored by 27 primers and 284 bands of them were polymorphic. The average polymorphic bands of each primer were 10.52. At species level, there was a high level of genetic diversity among six populations (PPB = 79.27%, N(e) = 1.332 7, H = 0.210 9 and H(sp) = 0.328 6). At population level, the genetic diversity level was low (PPB = 10.48% (4.00% -23.71%), N(e) = 1.048 7 (1.020 7-1.103 7), H = 0.029 7 (0.012 9-0.063 1), H(pop) = 0.046 2 (0.019 9-0.098 6). The Nei's coefficient of genetic differentiation was 0.841 1, which was consistent with the Shannon's coefficient of genetic differentiation (0.849 4). Two calculated methods all showed that most of the genetic variation existed among populations. The gene flow (N(m) = 0.094 4) was less among populations, indicating that the degree of genetic differentiation was higher. Genetic similarity coefficient were changed from 0.570 8 to 0.978 7. By clustering analysis, the tested populations were divided into two classes and had a tendency that the same geographical origin or material of similar habitats clustered into one group. The genetic diversity of samples of S. emodi is high,which laid a certain foundation for effective protection and improvement of germplasm resources.

Variability of cutaneous and nasal population levels between patients colonized and infected by multidrug-resistant bacteria in two Brazilian intensive care units.

PubMed

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.

Potentially traumatic events have negative and positive effects on loneliness, depending on PTSD-symptom levels: evidence from a population-based prospective comparative study.

PubMed

van der Velden, Peter G; Pijnappel, Bas; van der Meulen, Erik

2018-02-01

Examine to what extent adults affected by recent potentially traumatic events (PTE) with different PTSD-symptom levels are more at risk for post-event loneliness than non-affected adults are in the same study period. We extracted data from the Dutch longitudinal LISS panel to measure pre-event loneliness (2011) and post-event loneliness (2013 and 2014), pre-event mental health problems (2011), PTE and PTSD symptoms (2012). This panel is based on a traditional random sample drawn from the population register by Statistics Netherlands. Results of the multinomial logistic regression analyses showed that affected adults with high levels of PTSD symptoms were more at risk for high levels of post-event loneliness than affected adults with very low PTSD-symptom levels and non-affected adults, while controlling for pre-event loneliness, pre-event mental health problems and demographics. However, affected adults with very low levels of PTSD symptoms compared to non-affected adults were less at risk for medium and high levels of post-event loneliness while controlling for the same variables. Yet, pre-event loneliness appeared to be the strongest independent predictor of loneliness at later stages: more than 80% with high pre-event levels had high post-event levels at both follow-ups. Remarkably, potentially traumatic events have depending on PTSD-symptom levels both negative and positive effects on post-event loneliness in favor of affected adults with very low PTSD symptoms levels. However, post-event levels at later stages are predominantly determined by pre-event loneliness levels.

The Group-Level Consequences of Sexual Conflict in Multigroup Populations

PubMed Central

Eldakar, Omar Tonsi; Gallup, Andrew C.

2011-01-01

In typical sexual conflict scenarios, males best equipped to exploit females are favored locally over more prudent males, despite reducing female fitness. However, local advantage is not the only relevant form of selection. In multigroup populations, groups with less sexual conflict will contribute more offspring to the next generation than higher conflict groups, countering the local advantage of harmful males. Here, we varied male aggression within-and between-groups in a laboratory population of water striders and measured resulting differences in local population growth over a period of three weeks. The overall pool fitness (i.e., adults produced) of less aggressive pools exceeded that of high aggression pools by a factor of three, with the high aggression pools essentially experiencing no population growth over the course of the study. When comparing the fitness of individuals across groups, aggression appeared to be under stabilizing selection in the multigroup population. The use of contextual analysis revealed that overall stabilizing selection was a product of selection favoring aggression within groups, but selected against it at the group-level. Therefore, this report provides further evidence to show that what evolves in the total population is not merely an extension of within-group dynamics. PMID:22039491

Population structure and genetic diversity of wild Helianthus species from Mozambique.

PubMed

Ribeiro, A; Gouveia, M; Bessa, A; Ferreira, A; Magumisse, A T; Manjate, M; Faria, T

2010-08-01

The production of sunflower suffered a major decline in Mozambique after its independence in 1975. Civil war, human activities and environmental damage subjected the species to an ecological stress contributing to reduce the number and size of wild populations. As this reduction is often related to a loss of genetic variation we estimated the genetic diversity within and among populations of wild Helianthus from five districts of Mozambique using RAPD markers. The 44 accessions studied grouped into four major clusters exhibiting structured variability with regard to geographic origin. A high level of genetic diversity (He = 0.350 and I = 0.527) was retained at the population level. The genetic variation among populations was high (59.7%), which is consistent with low gene flow (Nm = 0.338). The proportion of total genetic diversity residing among these populations should be kept in mind to devise different conservation strategies in order to preserve these populations. Currently wild Helianthus genetic resources present in Maputo and Sofala are on the edge of extinction mainly due to excessive urbanization. Therefore, conservation of what remains of this plant genetic diversity is essential for sustainable utilization and can be useful for breeding programs.

Variation in sensitivity of large benthic Foraminifera to the combined effects of ocean warming and local impacts.

PubMed

Prazeres, Martina; Roberts, T Edward; Pandolfi, John M

2017-03-23

Large benthic foraminifera (LBF) are crucial marine calcifiers in coral reefs, and sensitive to environmental changes. Yet, many species successfully colonise a wide range of habitats including highly fluctuating environments. We tested the combined effects of ocean warming, local impacts and different light levels on populations of the common LBF Amphistegina lobifera collected along a cross-shelf gradient of temperature and nutrients fluctuations. We analysed survivorship, bleaching frequency, chlorophyll a content and fecundity. Elevated temperature and nitrate significantly reduced survivorship and fecundity of A. lobifera across populations studied. This pattern was exacerbated when combined with below optimum light levels. Inshore populations showed a consistent resistance to increased temperature and nitrate levels, but all populations studied were significantly affected by light reduction. These findings demonstrated the capacity of some populations of LBF to acclimate to local conditions; nonetheless improvements in local water quality can ultimately ameliorate effects of climate change in local LBF populations.

Susceptibility to neonicotinoids and risk of resistance development in the brown planthopper, Nilaparvata lugens (Stål) (Homoptera: Delphacidae).

PubMed

Wang, Yanhua; Chen, Jin; Zhu, Yu Cheng; Ma, Chongyong; Huang, Yue; Shen, Jinliang

2008-12-01

In recent years, outbreaks of the brown planthopper, Nilaparvata lugens (Stål), have occurred more frequently in China. The objective of this study was to determine the susceptibility of N. lugens to neonicotinoids and other insecticides in major rice production areas in China. Results indicated that substantial variations in the susceptibility to different insecticides existed in N. lugens. Field populations had developed variable resistance levels to neonicotinoids, with a high resistance level to imidacloprid (RR: 135.3-301.3-fold), a medium resistance level to imidaclothiz (RR: 35-41.2-fold), a low resistance level to thiamethoxam (up to 9.9-fold) and no resistance to dinotefuran, nitenpyram and thiacloprid (RR < 3-fold). Further examinations indicated that a field population had developed medium resistance level to fipronil (up to 10.5-fold), and some field populations had evolved a low resistance level to buprofezin. In addition, N. lugens had been able to develop 1424-fold resistance to imidacloprid in the laboratory after the insect was selected with imidacloprid for 26 generations. Long-term use of imidacloprid in a wide range of rice-growing areas might be associated with high levels of resistance in N. lugens. Therefore, insecticide resistance management strategies must be developed to prevent further increase in resistance.

Human genomic regions with exceptionally high levels of population differentiation identified from 911 whole-genome sequences.

PubMed

Colonna, Vincenza; Ayub, Qasim; Chen, Yuan; Pagani, Luca; Luisi, Pierre; Pybus, Marc; Garrison, Erik; Xue, Yali; Tyler-Smith, Chris; Abecasis, Goncalo R; Auton, Adam; Brooks, Lisa D; DePristo, Mark A; Durbin, Richard M; Handsaker, Robert E; Kang, Hyun Min; Marth, Gabor T; McVean, Gil A

2014-06-30

Population differentiation has proved to be effective for identifying loci under geographically localized positive selection, and has the potential to identify loci subject to balancing selection. We have previously investigated the pattern of genetic differentiation among human populations at 36.8 million genomic variants to identify sites in the genome showing high frequency differences. Here, we extend this dataset to include additional variants, survey sites with low levels of differentiation, and evaluate the extent to which highly differentiated sites are likely to result from selective or other processes. We demonstrate that while sites with low differentiation represent sampling effects rather than balancing selection, sites showing extremely high population differentiation are enriched for positive selection events and that one half may be the result of classic selective sweeps. Among these, we rediscover known examples, where we actually identify the established functional SNP, and discover novel examples including the genes ABCA12, CALD1 and ZNF804, which we speculate may be linked to adaptations in skin, calcium metabolism and defense, respectively. We identify known and many novel candidate regions for geographically restricted positive selection, and suggest several directions for further research.

High levels of genetic diversity in Spodoptera exempta NPV from Tanzania.

PubMed

Redman, Elizabeth M; Wilson, Kenneth; Grzywacz, David; Cory, Jenny S

2010-10-01

The African armyworm, Spodoptera exempta, is a major pest in sub-Saharan Africa. A nucleopolyhedrovirus (NPV) is often recorded in later population outbreaks and can cause very high levels of mortality. Research has been addressing whether this NPV can be developed into a strategic biological control agent. As part of this study, the variation in natural populations of NPV is being studied. An isolate of S. exempta NPV was cloned in vivo and found to contain at least 17 genetically-distinct genotypes. These genotypes varied in size from approximately 115 to 153 kb. Copyright 2010 Elsevier Inc. All rights reserved.

Increased extinction potential of insular fish populations with reduced life history variation and low genetic diversity.

PubMed

Hellmair, Michael; Kinziger, Andrew P

2014-01-01

Theoretical work has shown that reduced phenotypic heterogeneity leads to population instability and can increase extinction potential, yet few examples exist of natural populations that illustrate how varying levels expressed diversity may influence population persistence, particularly during periods of stochastic environmental fluctuation. In this study, we assess levels of expressed variation and genetic diversity among demographically independent populations of tidewater goby (Eucyclogobius newberryi), show that reductions in both factors typically coincide, and describe how low levels of diversity contribute to the extinction risk of these isolated populations. We illustrate that, for this annual species, continuous reproduction is a safeguard against reproductive failure by any one population segment, as natural, stochastically driven salinity increases frequently result in high mortality among juvenile individuals. Several study populations deviated from the natural pattern of year-round reproduction typical for the species, rendering those with severely truncated reproductive periods vulnerable to extinction in the event of environmental fluctuation. In contrast, demographically diverse populations are more likely to persist through such periods through the continuous presence of adults with broader physiological tolerance to abrupt salinity changes. Notably, we found a significant correlation between genetic diversity and demographic variation in the study populations, which could be the result of population stressors that restrict both of these diversity measures simultaneously, or suggestive of a causative relationship between these population characteristics. These findings demonstrate the importance of biocomplexity at the population level, and assert that the maintenance of diversity contributes to population resilience and conservation of this endangered species.

[Spanish Adaptation of the 2016 European Guidelines on Cardiovascular Disease Prevention in Clinical Practice].

PubMed

Royo-Bordonada, Miguel Angel; Armario, Pedro; Lobos Bejarano, José María; Pedro-Botet, Juan; Villar Álvarez, Fernando; Elosua, Roberto; Brotons Cuixart, Carlos; Cortés, Olga; Serrano, Benilde; Camafort Babkowski, Miguel; Gil Núñez, Antonio; Pérez, Antonio; Maiques, Antonio; de Santiago Nocito, Ana; Castro, Almudena; Alegría, Eduardo; Baeza, Ciro; Herranz, María; Sans, Susana; Campos, Pilar

2016-11-24

The VI European Guidelines for Cardiovascular Prevention recommend combining population and high-risk strategies with lifestyle changes as a cornerstone of prevention, and propose the SCORE function to quantify cardiovascular risk. The guidelines highlight disease specific interventions, and conditions as women, young people and ethnic minorities. Screening for subclinical atherosclerosis with noninvasive imaging techniques is not recommended. The guidelines distinguish four risk levels (very high, high, moderate and low) with therapeutic objectives for lipid control according to risk. Diabetes mellitus confers a high risk, except for subjects with type 2 diabetes with less than 10 years of evolution, without other risk factors or complications, or type 1 diabetes of short evolution without complications. The decision to start pharmacological treatment of arterial hypertension will depend on the blood pressure level and the cardiovascular risk, taking into account the lesion of target organs. The guidelines don't recommend antiplatelet drugs in primary prevention because of the increased bleeding risk. The low adherence to the medication requires simplified therapeutic regimes and to identify and combat its causes. The guidelines highlight the responsibility of health professionals to take an active role in advocating evidence-based interventions at the population level, and propose effective interventions, at individual and population level, to promote a healthy diet, the practice of physical activity, the cessation of smoking and the protection against alcohol abuse.

Brain Areas Involved in Anticipation of Clinically Relevant Pain in Low Back Pain Populations With High Levels of Pain Behavior.

PubMed

Lloyd, Donna M; Helbig, Torben; Findlay, Gordon; Roberts, Neil; Nurmikko, Turo

2016-05-01

The purpose of this study was to identify neural correlates of pain anticipation in people with nonspecific low back pain (NSLBP) that correlated with pain-related distress and disability, thus providing evidence for mechanisms underlying pain behavior in this population. Thirty NSLBP sufferers, with either high levels of pain behavior or low levels on the basis of Waddell signs, were scanned with functional magnetic resonance imaging while a straight-leg raise (of the side deemed to cause moderate pain in the lower back) was performed. On each trial colored stimuli were presented and used to indicate when the leg definitely would be raised (green; 100% certainty), might be raised (yellow; 50% certainty), or would definitely not be raised (red; 100% certainty). In response to expected versus unexpected pain the group difference in activation between patients with high levels of pain behavior and low levels of pain behavior covaried as a function of anxiety scores in the right insula and pregenual anterior cingulate cortex and as a function of catastrophizing in prefrontal and parietal cortex and hippocampus. The results suggest NSLBP populations with the highest levels of pain-related distress are more likely to attend to and infer threat from innocuous cues, which may contribute to the maintenance of pain behavior associated with some chronic pain states. This article shows a likely neural network for exacerbating pain anticipation in NSLBP contributing to high levels of pain behavior in some people. This information could potentially help clinicians and patients to understand how anticipation of pain may contribute to patient pain and disability. Copyright © 2016 American Pain Society. Published by Elsevier Inc. All rights reserved.

Variations in sub-national road traffic fatality trends in a low-income country.

PubMed

Bhatti, Junaid A; Khoso, Ajmal Khan; Waseem, Hunniya; Khan, Uzma Rahim; Razzak, Junaid A

2013-01-01

In most low- and middle-income countries (LMICs), road traffic fatality (RTF) trends are presented in aggregated form at the national level. This practice omits important information regarding RTF risk at sub-national levels. This ecological study assesses the extent of RTF variations at different sub-national levels in Pakistan, a low-income country. Based on official statistics, significant variations in three RTF indicators i.e. per population, per registered vehicles, and per crash were compared by regression analyses at two sub-national levels i.e. provincially (2000-2009) and district-wise (2004). The national RTF counts are based on data from four provinces. From 2000 to 2009, RTF per population and per registered vehicles decreased in all provinces except Balochistan. RTF per crash in Punjab decreased from 0.61 to 0.56 (beta coefficient (β) year = -0.0082, P = <0.001), whereas in Balochistan it increased from 0.40 to 0.58 (β year = 0.0708, P = <0.001) over the same period. District-level comparisons were possible only in Punjab where RTF per crash varied from 0.25 to 2.15 and correlated (β = 0.50, P = 0.003) with RTF per population. Sub-national RTF surveillance is necessary in LMICs like Pakistan in order to prioritize available resources on high-risk jurisdictions such as the Balochistan province and districts of Punjab where high RTF per population and per crash exist.

Sea-Level Rise and Land Subsidence in Deltas: Estimating Future Flood Risk Through Integrated Natural and Human System Modeling

NASA Astrophysics Data System (ADS)

Tessler, Z. D.; Vorosmarty, C. J.

2016-12-01

Deltas are highly sensitive to local human activities, land subsidence, regional water management, global sea-level rise, and climate extremes. We present a new delta flood exposure and risk framework for estimating the sensitivity of deltas to relative sea-level rise. We have applied this framework to a set of global environmental, geophysical, and social indicators over 48 major river deltas to quantify how contemporary risks vary across delta systems. The risk modeling framework incorporates upstream sediment flux and coastal land subsidence models, global empirical estimates of contemporary storm surge exposure, and population distribution and growth. Future scenarios are used to test the impacts on coastal flood risk of upstream dam construction, coastal population growth, accelerated sea-level rise, and enhanced storm surge. Results suggest a wide range of outcomes across different delta systems within each scenario. Deltas in highly engineered watersheds (Mississippi, Rhine) exhibit less sensitivity to increased dams due to saturation of sediment retention effects, though planned or under-construction dams are expected to have a substantial impact in the Yangtze, Irrawaddy, and Magdalena deltas. Population growth and sea-level rise are expected to be the dominant drivers of increased human risk in most deltas, with important exceptions in several countries, particularly China, where population are forecast to contract over the next several decades.

High MHC diversity maintained by balancing selection in an otherwise genetically monomorphic mammal

PubMed Central

Aguilar, Andres; Roemer, Gary; Debenham, Sally; Binns, Matthew; Garcelon, David; Wayne, Robert K.

2004-01-01

The San Nicolas Island fox (Urocyon littoralis dickeyi) is genetically the most monomorphic sexually reproducing animal population yet reported and has no variation in hypervariable genetic markers. Such low levels of variation imply lower resistance to pathogens, reduced fitness, and problems in distinguishing kin from non-kin. In vertebrates, the MHC contains genes that influence disease resistance and kin recognition and may be under intense balancing selection in some populations. Hence, genetic variation at the MHC might persist despite the extreme monomorphism shown by neutral markers. We examine variation of five loci within the MHC of San Nicolas Island foxes and find remarkably high levels of variation. Further, we show by simulation that genetic monomorphism at neutral loci and high MHC variation could arise only through an extreme population bottleneck of <10 individuals, ≈10–20 generations ago, accompanied by unprecedented selection coefficients of >0.5 on MHC loci. These results support the importance of balancing selection as a mechanism to maintain variation in natural populations and expose the difficulty of using neutral markers as surrogates for variation in fitness-related loci. PMID:14990802

Revisiting the Genetic Ancestry of Brazilians Using Autosomal AIM-Indels

PubMed Central

Saloum de Neves Manta, Fernanda; Pereira, Rui; Vianna, Romulo; Rodolfo Beuttenmüller de Araújo, Alfredo; Leite Góes Gitaí, Daniel; Aparecida da Silva, Dayse; de Vargas Wolfgramm, Eldamária; da Mota Pontes, Isabel; Ivan Aguiar, José; Ozório Moraes, Milton; Fagundes de Carvalho, Elizeu; Gusmão, Leonor

2013-01-01

There are many different studies that contribute to the global picture of the ethnic heterogeneity in Brazilian populations. These studies use different types of genetic markers and are focused on the comparison of populations at different levels. In some of them, each geographical region is treated as a single homogeneous population, whereas other studies create different subdivisions: political (e.g., pooling populations by State), demographic (e.g., urban and rural), or ethnic (e.g., culture, self-declaration, or skin colour). In this study, we performed an enhanced reassessment of the genetic ancestry of ~ 1,300 Brazilians characterised for 46 autosomal Ancestry Informative Markers (AIMs). In addition, 798 individuals from twelve Brazilian populations representing the five geographical macro-regions of Brazil were newly genotyped, including a Native American community and a rural Amazonian community. Following an increasing North to South gradient, European ancestry was the most prevalent in all urban populations (with values up to 74%). The populations in the North consisted of a significant proportion of Native American ancestry that was about two times higher than the African contribution. Conversely, in the Northeast, Center-West and Southeast, African ancestry was the second most prevalent. At an intrapopulation level, all urban populations were highly admixed, and most of the variation in ancestry proportions was observed between individuals within each population rather than among population. Nevertheless, individuals with a high proportion of Native American ancestry are only found in the samples from Terena and Santa Isabel. Our results allowed us to further refine the genetic landscape of Brazilians while establishing the basis for the effective application of an autosomal AIM panel in forensic casework and clinical association studies within the highly admixed Brazilian populations. PMID:24073242

The population genetics of Quechuas, the largest native South American group: autosomal sequences, SNPs, and microsatellites evidence high level of diversity.

PubMed

Scliar, Marilia O; Soares-Souza, Giordano B; Chevitarese, Juliana; Lemos, Livia; Magalhães, Wagner C S; Fagundes, Nelson J; Bonatto, Sandro L; Yeager, Meredith; Chanock, Stephen J; Tarazona-Santos, Eduardo

2012-03-01

Elucidating the pattern of genetic diversity for non-European populations is necessary to make the benefits of human genetics research available to individuals from these groups. In the era of large human genomic initiatives, Native American populations have been neglected, in particular, the Quechua, the largest South Amerindian group settled along the Andes. We characterized the genetic diversity of a Quechua population in a global setting, using autosomal noncoding sequences (nine unlinked loci for a total of 16 kb), 351 unlinked SNPs and 678 microsatellites and tested predictions of the model of the evolution of Native Americans proposed by (Tarazona-Santos et al.: Am J Hum Genet 68 (2001) 1485-1496). European admixture is <5% and African ancestry is barely detectable in the studied population. The largest genetic distances were between African versus Quechua or Melanesian populations, which is concordant with the African origin of modern humans and the fact that South America was the last part of the world to be peopled. The diversity in the Quechua population is comparable with that of Eurasian populations, and the allele frequency spectrum based on resequencing data does not reflect a reduction in the proportion of rare alleles. Thus, the Quechua population is a large reservoir of common and rare genetic variants of South Amerindians. These results are consistent with and complement our evolutionary model of South Amerindians (Tarazona-Santos et al.: Am J Hum Genet 68 (2001) 1485-1496), proposed based on Y-chromosome data, which predicts high genomic diversity due to the high level of gene flow between Andean populations and their long-term effective population size. Copyright © 2012 Wiley Periodicals, Inc.

Influence of altitude and enhanced ultraviolet-B radiation on tuber production, seed viability, leaf pigments and morphology in the wild potato species Solanum kurtzianum Bitter & Wittm collected from an elevational gradient.

PubMed

Ibañez, V N; Berli, F J; Masuelli, R W; Bottini, R A; Marfil, C F

2017-08-01

Climate change could lead to an upward shift in plant distribution, exposing populations to higher levels of ultraviolet (UV)-B radiation. In the framework of an in situ strategy for conserving potato wild relatives, we evaluated the effect of high UV-B levels on natural population of Solanum kurtzianum. The hypothesis is that plants from naturally higher altitudes are more adapted to increased UV-B radiation. Two populations from low and high altitudes were field supplemented using UV-B-lamps (+UV-B) or excluded from it with plastic filters. Additionally, to assess in which extent the plant responses to these artificial experimental conditions are reproducible in natural conditions, three genotypes were cultivated in two mountain experimental gardens (EG) at different elevations. +UV-B treatment induced changes in leaf morphology and increases in phenolic compounds in both populations, indicating plant adaptation, since chlorophylls and reproductive structures were not negatively affected. These results indicate that this environmental factor may not limit the displacement of populations towards sites with higher UV-B levels. Meanwhile, in higher-altitude EG a tubers yield reduction, mainly through a decreased tuber number and a bigger accumulation of phenolic compounds than in +UV-B treatment were observed, suggesting that UV-B is not the only factor involved in plants adaptation to high altitude environments. Copyright © 2017. Published by Elsevier B.V.

Genetic Diversity and Spatial Genetic Structure of the Grassland Perennial Saxifraga granulata along Two River Systems

PubMed Central

van der Meer, Sascha; Jacquemyn, Hans

2015-01-01

Due to changes in land use, the natural habitats of an increasing number of plant species have become more and more fragmented. In landscapes that consist of patches of suitable habitat, the frequency and extent of long-distance seed dispersal can be expected to be an important factor determining local genetic diversity and regional population structure of the remaining populations. In plant species that are restricted to riparian habitats, rivers can be expected to have a strong impact on the dynamics and spatial genetic structure of populations as they may enable long-distance seed dispersal and thus maintain gene flow between fragmented populations. In this study, we used polymorphic microsatellite markers to investigate the genetic diversity and the spatial genetic structure of 28 populations of Saxifraga granulata along two rivers in central Belgium. We hypothesized that rivers might be essential for gene flow among increasingly isolated populations of this species. Genetic diversity was high (HS = 0.68), which to a certain extent can be explained by the octoploid nature of S. granulata in the study area. Populations along the Dijle and Demer rivers were also highly differentiated (G” ST = 0.269 and 0.164 and D EST = 0.190 and 0.124, respectively) and showed significant isolation-by-distance, indicating moderate levels of gene flow primarily between populations that are geographically close to each other. Along the river Demer population genetic diversity was higher upstream than downstream, suggesting that seed dispersal via the water was not the primary mode of dispersal. Overall, these results indicate that despite increasing fragmentation populations along both rivers were highly genetically diverse. The high ploidy level and longevity of S. granulata have most likely buffered negative effects of fragmentation on genetic diversity and the spatial genetic structure of populations in riparian grasslands. PMID:26079603

[Demographic processes in the Amur region under conditions of economics reform in Russia].

PubMed

D'iachenko, V G

2000-01-01

Demographic and migration processes are analyzed for the Amur region, a typical Far-Eastern Russian territory with low density of population, in the historical and modern aspects. Low birth rate, high mortality, and negative natural increment of population reflect the social and economic reforms of the nineties in the Russian Far East. Demographic situation and migration processes in Asian and Pacific countries neighboring the Russian Far East are characterized by positive tendencies (high birth rate, natural increment in population number, and tendencies of migration of the capable population from densely populated central and Southern provinces to little populated Eastern provinces). According to the demographic prognosis, during the nearest decades we shall witness acute shortage of working resources in the Amur region, which will stimulate the already high flow of foreign manpower from the neighboring countries (China and Northern Korea). This necessitates urgent stabilizing measures at the local and federal levels.

Sources and assessment of occupational stress in the police.

PubMed

Deschamps, Frédéric; Paganon-Badinier, Isabelle; Marchand, Annie-Claude; Merle, Corinne

2003-11-01

The role of the police in Western society is undergoing a transformation that reflects the economic social and technological changes in the community and the assertion of individual rights within a democracy. The aim of this study is to evaluate level of stress among a group of French policemen and to examine the association between policing, potential stressors and stress levels. The sample is drawn from a large metropolitan police force (n=617). The population extends from the first line policeman to top senior management. Each policeman is matched for age (more or less five years) and sex, to a control. Policemen and controls complete a self administered questionnaire including demographic, occupational and health characteristics, and a stress level assessment with the help of a visual analogue scale. The average age of the two groups is 40 yr. Eighty-four percent are men. The total score for average sources is not statistically significantly different for policemen and controls. Comparison of a police group with a high stress level to a police population with a low and moderate stress level is made. The comparison is done first only with men, and second with the whole population. Policemen with a high stress level (same results only for men and the whole population) belong to the following groups: more than 15 yr service, sergeant, officer and administrative employee rank, divorced experience, age over 30, no leisure-time activities and no hobbies. Multivariate analysis shows that the two last parameters are bound to the stress level. For the whole population, age over 30 has to be added, and for the group of men, length of service over five years should be noted. Stress at work is an ill-health provoking factor. Police from minority groups such as ageing subjects or police officers have been reported to experience greater stress. This population is adversely affected by lack of available manpower and long working hours. In fact sources of stress in the police population are found both in the weariness of the job and private life planning.

A modified dual-level algorithm for large-scale three-dimensional Laplace and Helmholtz equation

NASA Astrophysics Data System (ADS)

Li, Junpu; Chen, Wen; Fu, Zhuojia

2018-01-01

A modified dual-level algorithm is proposed in the article. By the help of the dual level structure, the fully-populated interpolation matrix on the fine level is transformed to a local supported sparse matrix to solve the highly ill-conditioning and excessive storage requirement resulting from fully-populated interpolation matrix. The kernel-independent fast multipole method is adopted to expediting the solving process of the linear equations on the coarse level. Numerical experiments up to 2-million fine-level nodes have successfully been achieved. It is noted that the proposed algorithm merely needs to place 2-3 coarse-level nodes in each wavelength per direction to obtain the reasonable solution, which almost down to the minimum requirement allowed by the Shannon's sampling theorem. In the real human head model example, it is observed that the proposed algorithm can simulate well computationally very challenging exterior high-frequency harmonic acoustic wave propagation up to 20,000 Hz.

The Association between Natural Amenities, Rural Population Growth, and Long-Term Residents' Economic Well-Being

ERIC Educational Resources Information Center

Hunter, Lori M; Boardman, Jason D.; Saint Onge, Jarron M.

2005-01-01

Population growth in rural areas characterized by high levels of natural amenities has recently received substantial research attention. A noted concern with amenity-driven rural population growth is its potential to raise local costs-of-living while yielding only low-wage service sector employment for long-term residents. The work presented here…

Population genetic structure of the point-head flounder, Cleisthenes herzensteini, in the Northwestern Pacific.

PubMed

Xiao, Yongshuang; Zhang, Yan; Yanagimoto, Takashi; Li, Jun; Xiao, Zhizhong; Gao, Tianxiang; Xu, Shihong; Ma, Daoyuan

2011-02-01

Intraspecific phylogenies can provide useful insights into how populations have been shaped by historical and contemporary processes. To determine the population genetic structure and the demographic and colonization history of Cleisthenes herzensteini in the Northwestern Pacific, one hundred and twenty-one individuals were sampled from six localities along the coastal regions of Japan and the Yellow Sea of China. Mitochondrial DNA variation was analyzed using DNA sequence data from the 5' end of control region. High levels of haplotype diversity (>0.96) were found for all populations, indicating a high level of genetic diversity. No pattern of isolation by distance was detected among the population differentiation throughout the examined range. Analyses of molecular variance (AMOVA) and the conventional population statistic Fst revealed no significant population genetic structure among populations. According to the exact test of differentiation among populations, the null hypothesis that C. herzensteini within the examined range constituted a non-differential mtDNA gene pool was accepted. The demographic history of C. herzensteini was examined using neutrality test and mismatch distribution analyses and results indicated Pleistocene population expansion (about 94-376 kya) in the species, which was consistent with the inference result of nested clade phylogeographical analysis (NCPA) showing contiguous range expansion for C. herzensteini. The lack of phylogeographical structure for the species may reflect a recent range expansion after the glacial maximum and insufficient time to attain migration-drift equilibrium.

Anticardiolipin antibodies in patients from Malaysia with systemic lupus erythematosus.

PubMed

Jones, H W; Ireland, R; Senaldi, G; Wang, F; Khamashta, M; Bellingham, A J; Veerapan, K; Hughes, G R; Vergani, D

1991-03-01

Systemic lupus erythematosus (SLE) is highly prevalent in Malaysia, which has a mixed population of Malays, Chinese, and Indians. A quantitative enzyme linked immunosorbent assay (ELISA) was used to determine anticardiolipin antibody (aCL) levels (total immunoglobulin, IgG, and IgM) in 200 patients with SLE (164 Chinese, 26 Malay, and 10 Indian) attending the University Hospital of Kuala Lumpur, Malaysia, and 103 matched controls. Only 33 (16.5%) of the patients had raised aCL levels; 26 had raised IgG aCL, five IgM aCL, and two both IgG and IgM aCL. There was a low prevalence of raised levels of aCL in the population studied, which was seen in conjunction with a rare occurrence of thrombosis. The classical association of high aCL levels with thrombocytopenia and recurrent abortions was noted, though not with cerebral disease. The low prevalence of aCL in this study population of mixed racial origin contrasts with findings in European patients with SLE and lends support to the influence of local factors, be they genetic or environmental, on the clinical manifestations of this disease.

Educational Attainment by Age, Sex, and Race, for the United States: 1970. 1970 Census of Population, Supplementary Report.

ERIC Educational Resources Information Center

Bureau of the Census (DOC), Suitland, MD. Population Div.

The 1960's witnessed considerable change in educational attainment levels. Of Americans 25 years old and over in 1970, 52 percent were at least high school graduates, as compared with 41 percent in 1960 and 34 percent in 1950. There was considerable variation in educational attainment levels in 1970 among the various age groups in the population.…

GPX1 Pro198Leu polymorphism and GSTM1 deletion do not affect selenium and mercury status in mildly exposed Amazonian women in an urban population.

PubMed

Rocha, Ariana V; Rita Cardoso, Bárbara; Zavarize, Bruna; Almondes, Kaluce; Bordon, Isabella; Hare, Dominic J; Teixeira Favaro, Déborah Inês; Franciscato Cozzolino, Silvia Maria

2016-11-15

Mercury is potent toxicant element, but its toxicity can be reduced by forming a complex with selenium for safe excretion. Considering the impact of mercury exposure in the Amazon region and the possible interaction between these two elements, we aimed to assess the effects of Pro198Leu polymorphism to GPX1 and GSTM1 deletion, on mercury levels in a population from Porto Velho, an urban locality in the Brazilian Amazon region. Two hundred women from the capital city of Rondônia state were recruited for this study with 149 deemed suitable to participate. We assessed dietary intake using 24-hour recall. Selenium levels in plasma and erythrocytes were measured using hydride generation quartz tube atomic absorption spectroscopy and total hair mercury using cold vapor atomic absorption spectrometry. Oxidative stress parameters (GPx activity, oxygen radical absorbency capacity [ORAC] and malondialdehyde [MDA]) were also analyzed. All participants were genotyped for Pro198Leu polymorphism and GSTM1 deletion. We observed that this population presented high prevalence of selenium deficiency, and also low levels of mercury, likely due to food habits that did not include selenium-rich food sources or significant consumption of fish (mercury biomagnifiers) regularly. Univariate statistical analysis showed that Pro198Leu and GSTM1 genotypes did not affect selenium and mercury levels in this population. Pro198Leu polymorphism and GSTM1 deletion had no effect on mercury levels in mildly exposed people, suggesting these genetic variants impact mercury levels only in highly exposed populations. Copyright © 2016 Elsevier B.V. All rights reserved.

Validation of TICS for detection of dementia and mild cognitive impairment among individuals characterized by low levels of education or illiteracy: a population-based study in rural Greece.

PubMed

Georgakis, Marios K; Papadopoulos, Fotios C; Beratis, Ion; Michelakos, Theodoros; Kanavidis, Prodromos; Dafermos, Vasilios; Tousoulis, Dimitrios; Papageorgiou, Sokratis G; Petridou, Eleni Th

2017-01-01

The efficacy of the most widely used tests for dementia screening is limited in populations characterized by low levels of education. This study aimed to validate the face-to-face administered Telephone Interview for Cognitive Status (TICS) for detection of dementia and mild cognitive impairment (MCI) in a population-based sample of community dwelling individuals characterized by low levels of education or illiteracy in rural Greece. The translated Greek version of TICS was administered through face-to-face interview in 133 elderly residents of Velestino of low educational level (<12 years). We assessed its internal consistency and test-retest reliability, its correlation with sociodemographic parameters, and its discriminant ability for cognitive impairment and dementia, as defined by a brief neurological evaluation, including assessment of cognitive status and level of independence. TICS was characterized by adequate internal consistency (Cronbach's α: .72) and very high test-retest reliability (intra-class correlation coefficient: .93); it was positively correlated with age and educational years. MCI and dementia were diagnosed in 18 and 10.5% of the population, respectively. Its discriminant ability for detection of dementia was high (Area under the curve, AUC: .85), with a sensitivity and specificity of 86 and 82%, respectively, at a cut-off point of 24/25. TICS did not perform well in differentiating MCI from cognitively normal individuals though (AUC: .67). The directly administered TICS questionnaire provides an easily applicable and brief option for detection of dementia in populations of low educational level and might be useful in the context of both clinical and research purposes.

The Child Opportunity Index and Disparities in Pediatric Asthma Hospitalizations Across One Ohio Metropolitan Area, 2011-2013.

PubMed

Beck, Andrew F; Huang, Bin; Wheeler, Kathryn; Lawson, Nikki R; Kahn, Robert S; Riley, Carley L

2017-11-01

To determine whether the Child Opportunity Index (COI), a nationally available measure of relative educational, health/environmental, and social/economic opportunity across census tracts within metropolitan areas, is associated with population- and patient-level asthma morbidity. This population-based retrospective cohort study was conducted between 2011 and 2013 in a southwest Ohio county. Participants included all children aged 1-16 years with hospitalizations or emergency department visits for asthma or wheezing at a major pediatric hospital. Patients were identified using discharge diagnosis codes and geocoded to their home census tract. The primary population-level outcome was census tract asthma hospitalization rate. The primary patient-level outcome was rehospitalization within 12 months of the index hospitalization. Census tract opportunity was characterized using the COI and its educational, health/environmental, and social/economic domains. Across 222 in-county census tracts, there were 2539 geocoded hospitalizations. The median asthma-related hospitalization rate was 5.0 per 1000 children per year (IQR, 1.9-8.9). Median hospitalization rates in very low, low, moderate, high, and very high opportunity tracts were 9.1, 7.6, 4.6, 2.1, and 1.8 per 1000, respectively (P < .0001). The social/economic domain had the most variables significantly associated with the outcome at the population level. The adjusted patient-level analyses showed that the COI was not significantly associated with a patient's risk of rehospitalization within 12 months. The COI was associated with population-level asthma morbidity. The details provided by the COI may inform interventions aimed at increasing opportunity and reducing morbidity across regions. Copyright © 2017 Elsevier Inc. All rights reserved.

An airport community noise-impact assessment model

NASA Technical Reports Server (NTRS)

Deloach, R.

1980-01-01

A computer model was developed to assess the noise impact of an airport on the community which it serves. Assessments are made using the Fractional Impact Method by which a single number describes the community aircraft noise environment in terms of exposed population and multiple event noise level. The model is comprised of three elements: a conventional noise footprint model, a site specific population distribution model, and a dose response transfer function. The footprint model provides the noise distribution for a given aircraft operating scenario. This is combined with the site specific population distribution obtained from a national census data base to yield the number of residents exposed to a given level of noise. The dose response relationship relates noise exposure levels to the percentage of individuals highly annoyed by those levels.

Population genetic structure of Monimopetalum chinense (Celastraceae), an endangered endemic species of eastern China.

PubMed

Xie, Guo-Wen; Wang, De-Lian; Yuan, Yong-Ming; Ge, Xue-Jun

2005-04-01

Monimopetalum chinense (Celastraceae) standing for the monotypic genus is endemic to eastern China. Its conservation status is vulnerable as most populations are small and isolated. Monimopetalum chinense is capable of reproducing both sexually and asexually. The aim of this study was to understand the genetic structure of M. chinense and to suggest conservation strategies. One hundred and ninety individuals from ten populations sampled from the entire distribution area of M. chinense were investigated by using inter-simple sequence repeats (ISSR). A total of 110 different ISSR bands were generated using ten primers. Low levels of genetic variation were revealed both at the species level (Isp=0.183) and at the population level (Ipop=0.083). High clonal diversity (D = 0.997) was found, and strong genetic differentiation among populations was detected (49.06 %). Small population size, possible inbreeding, limited gene flow due to short distances of seed dispersal, fragmentation of the once continuous range and subsequent genetic drift, may have contributed to shaping the population genetic structure of the species.

Awareness of HPV and Uptake of Vaccination in a High-Risk Population.

PubMed

Fishman, Jessica; Taylor, Lynne; Frank, Ian

2016-08-01

Immunization against the human papillomavirus (HPV) is effective at preventing HPV-related cancers, but vaccination rates have remained low. Levels of awareness could conceivably influence vaccination rates, but currently the relationship is unknown. This is the first study to test how strongly levels of awareness among parents and adolescents are related to subsequent HPV vaccination among a high-risk population of adolescents. This longitudinal cohort study measured baseline levels of awareness (about HPV, cervical cancer, HPV vaccination, and news or advertisements about HPV vaccination) among parents of adolescents and also a separate sample of adolescents. Participants resided in predominantly low-income, African American neighborhoods of a large American city. During a 12-month follow-up period, the outcome measures were defined as adolescent receipt of any HPV vaccination, as measured by clinic records. Within 1 year, <16% of adolescents received vaccination. The relationship between awareness and subsequent vaccination was either not statistically significant or not meaningful in magnitude, with R(2) = 0.004 to 0.02. The predicted probability of getting vaccination was <0.50 for all awareness levels and prediction accuracy was poor (area under the curve = 0.56-0.64). In this high-risk population, levels of awareness among parents and adolescents were not substantially related to subsequent adolescent HPV vaccination. Copyright © 2016 by the American Academy of Pediatrics.

Chronic fatigue in Hodgkin lymphoma survivors and associations with anxiety, depression and comorbidity

PubMed Central

Daniëls, L A; Oerlemans, S; Krol, A D G; Creutzberg, C L; van de Poll-Franse, L V

2014-01-01

Background: Fatigue is a frequent and persistent problem among Hodgkin lymphoma (HL) survivors. We investigated the prevalence of clinically relevant fatigue in HL survivors and the relation between fatigue and anxiety and depression. Methods: Fatigue was measured through the generic European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (QLQ-C30) and Fatigue Assessment Scale (FAS). Anxiety and depression were measured with the Hospital Anxiety and Depression Scale. Questionnaires were mailed to 267 HL survivors. Results were compared with a Dutch age-matched normative population. Results: Response rate was 68% (median age 46 years, mean time since diagnosis 4.6 years). Prevalence of fatigue was significantly higher among HL survivors than in the norm population (FAS 41% vs 23%, QLQ-C30 43% vs 28%), as were fatigue levels. There was a significant association between fatigue, anxiety and depression. Of the HL survivors with high symptom levels of depression, 97% also reported fatigue. In multivariate analysis, depression was strongly associated with high levels of fatigue and, to a lesser extent, anxiety and comorbidity. Conclusions: Prevalence rates of fatigue are significantly higher in HL survivors than in the general population and differences are clinically relevant. Depression and anxiety were strongly associated with high levels of fatigue. Reducing fatigue levels by treatment of depression and anxiety should be further explored. PMID:24434433

Influence of terrestrial radionuclides on environmental gamma exposure in a uranium deposit in Paraíba, Brazil.

PubMed

Araújo Dos Santos Júnior, José; Dos Santos Amaral, Romilton; Simões Cezar Menezes, Rômulo; Reinaldo Estevez Álvarez, Juan; Marques do Nascimento Santos, Josineide; Herrero Fernández, Zahily; Dias Bezerra, Jairo; Antônio da Silva, Alberto; Francys Rodrigues Damascena, Kennedy; de Almeida Maciel Neto, José

2017-07-01

One of the main natural uranium deposits in Brazil is located in the municipality of Espinharas, in the State of Paraíba. This area may present high levels of natural radioactivity due to the presence of these radionuclides. Since this is a populated area, there is need for a radioecological dosimetry assessment to investigate the possible risks to the population. Based on this problem, the objective of this study was to estimate the environmental effective dose outdoors in inhabited areas influenced by the uranium deposit, using the specific activities of equivalent uranium, equivalent thorium and 40 K and conversion factors. The environmental assessment was carried using gamma spectroscopy in sixty-two points within the municipality, with a high-resolution gamma spectrometer with HPGe semiconductor detector and Be window. The results obtained ranged from 0.01 to 19.11 mSv y -1 , with an average of 2.64 mSv y -1 . These levels are, on average, 23 times higher than UNSCEAR reference levels and up to 273 times the reference value of the earth's crust for primordial radionuclides. Therefore, given the high radioactivity levels found, we conclude that there is need for further investigation to evaluate the levels of radioactivity in indoor environments, which will reflect more closely the risks of the local population. Copyright © 2017 Elsevier Inc. All rights reserved.

Comparative analyses of genetic/epigenetic diversities and structures in a wild barley species (Hordeum brevisubulatum) using MSAP, SSAP and AFLP.

PubMed

Shan, X H; Li, Y D; Liu, X M; Wu, Y; Zhang, M Z; Guo, W L; Liu, B; Yuan, Y P

2012-08-17

We analyzed genetic diversity and population genetic structure of four artificial populations of wild barley (Hordeum brevisubulatum); 96 plants collected from the Songnen Prairie in northeastern China were analyzed using amplified fragment length polymorphism (AFLP), specific-sequence amplified polymorphism (SSAP) and methylation-sensitive amplified polymorphism (MSAP) markers. Indices of (epi-)genetic diversity, (epi-)genetic distance, gene flow, genotype frequency, cluster analysis, PCA analysis and AMOVA analysis generated from MSAP, AFLP and SSAP markers had the same trend. We found a high level of correlation in the artificial populations between MSAP, SSAP and AFLP markers by the Mantel test (r > 0.8). This is incongruent with previous findings showing that there is virtually no correlation between DNA methylation polymorphism and classical genetic variation; the high level of genetic polymorphism could be a result of epigenetic regulation. We compared our results with data from natural populations. The population diversity of the artificial populations was lower. However, different from what was found using AFLP and SSAP, based on MSAP results the methylation polymorphism of the artificial populations was not significantly reduced. This leads us to suggest that the DNA methylation pattern change in H. brevisubulatum populations is not only related to DNA sequence variation, but is also regulated by other controlling systems.

Oil Spills and Marine Mammals in British Columbia, Canada: Development and Application of a Risk-Based Conceptual Framework.

PubMed

Jarvela Rosenberger, Adrianne L; MacDuffee, Misty; Rosenberger, Andrew G J; Ross, Peter S

2017-07-01

Marine mammals are inherently vulnerable to oil spills. We developed a conceptual framework to evaluate the impacts of potential oil exposure on marine mammals and applied it to 21 species inhabiting coastal British Columbia (BC), Canada. Oil spill vulnerability was determined by examining both the likelihood of species-specific (individual) oil exposure and the consequent likelihood of population-level effects. Oil exposure pathways, ecology, and physiological characteristics were first used to assign species-specific vulnerability rankings. Baleen whales were found to be highly vulnerable due to blowhole breathing, surface filter feeding, and invertebrate prey. Sea otters (Enhydra lutris) were ranked as highly vulnerable due to their time spent at the ocean surface, dense pelage, and benthic feeding techniques. Species-specific vulnerabilities were considered to estimate the likelihood of population-level effects occurring after oil exposure. Killer whale (Orcinus orca) populations were deemed at highest risk due to small population sizes, complex social structure, long lives, slow reproductive turnover, and dietary specialization. Finally, we related the species-specific and population-level vulnerabilities. In BC, vulnerability was deemed highest for Northern and Southern Resident killer whales and sea otters, followed by Bigg's killer whales and Steller sea lions (Eumetopias jubatus). Our findings challenge the typical "indicator species" approach routinely used and underscore the need to examine marine mammals at a species and population level for risk-based oil spill predictions. This conceptual framework can be combined with spill probabilities and volumes to develop more robust risk assessments and may be applied elsewhere to identify vulnerability themes for marine mammals.

Diabetes websites accredited by the Health On the Net Foundation Code of Conduct: readable or not?

PubMed

Kusec, Sanja; Brborovic, Ognjen; Schillinger, Dean

2003-01-01

Health information posted on the Internet has become a popular mode of communication with the population at large because millions of people now use the Internet to gather health information. Many studies on readability have shown that patient education information is frequently written at the reading level too high for the average population to understand, and the same holds true for health information on the Internet. The aim of this study was to determine the readability levels of health information found on diabetes-related websites displaying HONcode logo, which indicates to high quality of the information provided. The 99 websites tested for readability using the Flesch Reading Ease formula and Flesch-Kincaid level showed FRE score 2.1 to 79.6, with the mean 41.7 (10th grade, 8th month Flesch-Kincaid level), which indicates that 86.9% of these materials would be too difficult to read for the average adult population. It is suggested that the readability level, and the name of the formula used, be used on the websites themselves to help the Internet users decide which sites could be of the greatest benefit to them.

Increase in Population Density and Aggravation of Social and Psychological Problems in Areas with High-Rise Construction

NASA Astrophysics Data System (ADS)

Romanova, Elena

2018-03-01

High-rise apartment houses have technical and economic advantages in areas with dense population. Their placement in the central part of the city allows increasing the number of living space in the limited territory, to bring population to the place of employment and reduce pendular migration. But increase in population density leads to psychological problems: level of a stress, fatigue increases, the number of phobias grows, infectious diseases extend quicker. These problems can be solved at resettlement of inhabitants to the suburb. However such decision leads to aggravation of a transport problem and the pulsing increase in population density in the downtown and on its suburb. To solve a transport problem, it is necessary not to increase the square of the cities. Therefore in the suburbs is also used high-rise construction. But high-rise residential districts on the suburb of the city get own social problems which are capable to destroy all advantages of high-rise construction.

Aphid vector population density determines the emergence of necrogenic satellite RNAs in populations of cucumber mosaic virus.

PubMed

Betancourt, Mónica; Fraile, Aurora; Milgroom, Michael G; García-Arenal, Fernando

2016-06-01

The satellite RNAs of cucumber mosaic virus (CMV) that induce systemic necrosis in tomato plants (N-satRNA) multiply to high levels in the infected host while severely depressing CMV accumulation and, hence, its aphid transmission efficiency. As N-satRNAs are transmitted into CMV particles, the conditions for N-satRNA emergence are not obvious. Model analyses with realistic parameter values have predicted that N-satRNAs would invade CMV populations only when transmission rates are high. Here, we tested this hypothesis experimentally by passaging CMV or CMV+N-satRNAs at low or high aphid densities (2 or 8 aphids/plant). As predicted, high aphid densities were required for N-satRNA emergence. The results showed that at low aphid densities, random effects due to population bottlenecks during transmission dominate the epidemiological dynamics of CMV/CMV+N-satRNA. The results suggest that maintaining aphid populations at low density will prevent the emergence of highly virulent CMV+N-satRNA isolates.

Divide and conquer: intermediate levels of population fragmentation maximize cultural accumulation.

PubMed

Derex, Maxime; Perreault, Charles; Boyd, Robert

2018-04-05

Identifying the determinants of cumulative cultural evolution is a key issue in the interdisciplinary field of cultural evolution. A widely held view is that large and well-connected social networks facilitate cumulative cultural evolution because they promote the spread of useful cultural traits and prevent the loss of cultural knowledge through factors such as drift. This view stems from models that focus on the transmission of cultural information, without considering how new cultural traits actually arise. In this paper, we review the literature from various fields that suggest that, under some circumstances, increased connectedness can decrease cultural diversity and reduce innovation rates. Incorporating this idea into an agent-based model, we explore the effect of population fragmentation on cumulative culture and show that, for a given population size, there exists an intermediate level of population fragmentation that maximizes the rate of cumulative cultural evolution. This result is explained by the fact that fully connected, non-fragmented populations are able to maintain complex cultural traits but produce insufficient variation and so lack the cultural diversity required to produce highly complex cultural traits. Conversely, highly fragmented populations produce a variety of cultural traits but cannot maintain complex ones. In populations with intermediate levels of fragmentation, cultural loss and cultural diversity are balanced in a way that maximizes cultural complexity. Our results suggest that population structure needs to be taken into account when investigating the relationship between demography and cumulative culture.This article is part of the theme issue 'Bridging cultural gaps: interdisciplinary studies in human cultural evolution'. © 2018 The Author(s).

Childhood leukaemia in areas with different radon levels: a spatial and temporal analysis using GIS.

PubMed

Kohli, S; Noorlind Brage, H; Löfman, O

2000-11-01

To evaluate the relation between exposure to ground radon levels and leukaemia among children using existing population and disease registers. Ecological correlation study. The county of Ostergötland in Sweden. Every child born in the county between 1979 and 1992 was mapped to the property centroid coordinates by linking addresses in the population and property registers. Population maps were overlaid with radon maps and exposure at birth and each subsequent year was quantified as high, normal, low or unknown. This was analysed with data from the tumour registry. Standardised mortality ratios (SMRs) were calculated using the age and sex specific rates for Sweden for the year 1995. 90 malignancies occurred among 53 146 children (498 887 person years) who formed the study population. SMRs for acute lymphatic leukaemia (ALL) among children born in high, normal and low risk areas were 1.43, 1.17 and 0.25 respectively. The relative risk for the normal risk group and high risk group as compared with the low risk group was 4.64 (95% CI 1.29, 28.26) and 5. 67 (95% CI 1.06, 42.27). The association between ALL and continued residence at normal or high risk areas showed a similar trend. No association between radon risk levels and any other malignancy was seen. Children born in and staying at areas where the risk from ground radon has been classified as low are less likely to develop ALL than those born in areas classified as normal and high risk.

Cardiovascular Health Issues in Inner City Populations.

PubMed

Nayyar, Dhruv; Hwang, Stephen W

2015-09-01

Inner city populations in high-income countries carry a disproportionately high burden of cardiovascular disease. Although low individual socioeconomic status has long been associated with higher morbidity and mortality from cardiovascular disease, there is a growing body of evidence that area-level socioeconomic status may also have a major effect on cardiovascular outcomes. A lack of supermarkets, limited green space, and high rates of violent crime in inner city neighbourhoods result in poor dietary intake and low rates of physical activity among residents. The physical and social environments of inner city neighbourhoods may also contribute to high rates of comorbid mental illness in disadvantaged urban populations. Mental illness may lead to the clustering of cardiovascular risk factors through its impact on health behaviours, effects of psychiatric medications, and sequelae of substance abuse. Individuals residing in disadvantaged neighbourhoods experience reduced access to both primary preventive and acute in-hospital cardiovascular care. This may be driven by financial disincentives for caring for patients with low socioeconomic status, as well as system capacity issues in the inner city, and patient-level differences in health-seeking behaviours. Small-scale studies of interventions to improve individual-level health behaviours and access to care in the inner city have demonstrated some success in improving cardiovascular outcomes through the use of mobile clinics, health coaching, and case management approaches. There is a need for further research into community-wide interventions to improve the cardiovascular health of inner city populations. Copyright © 2015 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Normative data for the Digit Symbol Substitution Test in a population-based sample aged 65-79 years: Results from the German Health Interview and Examination Survey for Adults (DEGS1).

PubMed

Gaertner, Beate; Wagner, Michael; Luck, Tobias; Buttery, Amanda K; Fuchs, Judith; Busch, Markus A

2018-06-17

To provide normative data for the Digit Symbol Substitution Test (DSST) of the Wechsler Adult Intelligence Scale, 3rd edition (WAIS-III) in a population-based sample of community-dwelling older adults in Germany according to age, sex, and level of education. The sample comprised 1385 participants aged 65-79 years from the nationwide representative 'German Health Interview and Examination Survey for Adults' (DEGS1, 2008-2011). Participants with known cognitive impairment or dementia, other medical conditions affecting cognition, or currently using psychotropic drugs were excluded. Educational level was categorized as low, medium, and high according to the Comparative Analyses of Social Mobility in Industrial Nations (CASMIN) scale. Normative values for the DSST according to age, sex, and level of education were estimated by multiple linear regression using population weights. Mean age was 71.1 years, 48.6% were men and low, medium, and high education levels were 62.8, 24.6, and 12.6%, respectively. Younger age, female sex, and higher level of education were significantly associated with higher DSST scores. Regression-based normative data for the DSST is provided according to age, sex, and level of education. In addition, a normative score calculator is provided. These are the first age-, sex-, and education-specific normative data for older individuals for the DSST of the WAIS-III in Germany. These normative data will enable future population-level analyses on impaired cognitive function according to DSST.

Virginia: The State and Its Educational System.

ERIC Educational Resources Information Center

Hodgkinson, Harold L.

A profile of Virginia is presented, which assesses trends in the state's economy, population, and educational system. The state is characterized by a diverse economy, a well-educated suburban middle-class majority, a high level of individual and state wealth, and a high level of work force participation. Problems include rural poverty, lack of…

γ-ray decay from neutron-bound and unbound states in 95Mo and a novel technique for spin determination

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wiedeking, M.; Krticka, M.; Bernstein, L. A.

2016-02-01

The emission of γ rays from neutron-bound and neutron-unbound states in 95Mo, populated in the 94Mo(d,p) reaction, has been investigated. Charged particles and γ radiation were detected with arrays of annular silicon and Clover-type high-purity Germanium detectors, respectively. Utilizing p-γ and p-γ-γ coincidences, the 95Mo level scheme was greatly enhanced with 102 new transitions and 43 new states. It agrees well with shell model calculations for excitation energies below ≈2 MeV. From p-γ coincidence data, a new method for the determination of spins of discrete levels is proposed. The method exploits the suppression of high-angular momentum neutron emission from levelsmore » with high spins populated in the (d,p) reaction above the neutron separation energy. As a result, spins for almost all 95Mo levels below 2 MeV (and for a few levels above) have been determined with this method.« less

New insights for mesospheric OH: multi-quantum vibrational relaxation as a driver for non-local thermodynamic equilibrium

PubMed Central

Kalogerakis, Konstantinos S.; Matsiev, Daniel; Cosby, Philip C.; Dodd, James A.; Falcinelli, Stefano; Hedin, Jonas; Kutepov, Alexander A.; Noll, Stefan; Panka, Peter A.; Romanescu, Constantin; Thiebaud, Jérôme E.

2018-01-01

The question of whether mesospheric OH(υ) rotational population distributions are in equilibrium with the local kinetic temperature has been debated over several decades. Despite several indications for the existence of non-equilibrium effects, the general consensus has been that emissions originating from low rotational levels are thermalized. Sky spectra simultaneously observing several vibrational levels demonstrated reproducible trends in the extracted OH(υ) rotational temperatures as a function of vibrational excitation. Laboratory experiments provided information on rotational energy transfer and direct evidence for fast multi-quantum OH(high-υ) vibrational relaxation by O atoms. We examine the relationship of the new relaxation pathways with the behavior exhibited by OH(υ) rotational population distributions. Rapid OH(high-υ) + O multi-quantum vibrational relaxation connects high and low vibrational levels and enhances the hot tail of the OH(low-υ) rotational distributions. The effective rotational temperatures of mesospheric OH(υ) are found to deviate from local thermodynamic equilibrium for all observed vibrational levels. PMID:29503514

The contribution of area-level walkability to geographic variation in physical activity: a spatial analysis of 95,837 participants from the 45 and Up Study living in Sydney, Australia.

PubMed

Mayne, Darren J; Morgan, Geoffrey G; Jalaludin, Bin B; Bauman, Adrian E

2017-10-03

Individual-level studies support a positive relation between walkable built environments and participation in moderate-intensity walking. However, the utility of this evidence for population-level planning is less clear as it is derived at much finer spatial scales than those used for regional programming. The aims of this study were to: evaluate if individual-level relations between walkability and walking to improve health manifest at population-level spatial scales; assess the specificity of area-level walkability for walking relative to other moderate and vigorous physical activity (MVPA); describe geographic variation in walking and other MVPA; and quantify the contribution of walkability to this variation. Data on sufficient walking, sufficient MVPA, and high MVPA to improve health were analyzed for 95,837 Sydney respondents to the baseline survey of the 45 and Up Study between January 2006 and April 2010. We used conditional autoregressive models to create smoothed MVPA "disease maps" and assess relations between sufficient MVPA to improve health and area-level walkability adjusted for individual-level demographic, socioeconomic, and health factors, and area-level relative socioeconomic disadvantage. Within-cohort prevalence of meeting recommendations for sufficient walking, sufficient MVPA, and high MVPA were 31.7 (95% CI 31.4-32.0), 69.4 (95% CI 69.1-69.7), and 56.1 (95% CI 55.8-56.4) percent. Prevalence of sufficient walking was increased by 1.20 (95% CrI 1.12-1.29) and 1.07 (95% CrI 1.01-1.13) for high and medium-high versus low walkability postal areas, and for sufficient MVPA by 1.05 (95% CrI 1.01-1.08) for high versus low walkability postal areas. Walkability was not related to high MVPA. Postal area walkability explained 65.8 and 47.4 percent of residual geographic variation in sufficient walking and sufficient MVPA not attributable to individual-level factors. Walkability is associated with area-level prevalence and geographic variation in sufficient walking and sufficient MVPA to improve health in Sydney, Australia. Our study supports the use of walkability indexes at multiple spatial scales for informing population-level action to increase physical activity and the utility of spatial analysis for walkability research and planning.

Global importation and population risk factors for measles in New Zealand: a case study for highly immunized populations.

PubMed

Hayman, D T S; Marshall, J C; French, N P; Carpenter, T E; Roberts, M G; Kiedrzynski, T

2017-07-01

As endemic measles is eliminated through immunization, countries must determine the risk factors for the importation of measles into highly immunized populations to target control measures. Despite eliminating endemic measles, New Zealand suffers from outbreaks after introductions from abroad, enabling us to use it as a model for measles introduction risk. We used a generalized linear model to analyze risk factors for 1137 measles cases from 2007 to June 2014, provide estimates of national immunity levels, and model measles importation risk. People of European ethnicity made up the majority of measles cases. Age is a positive risk factor, particularly 0-2-year-olds and 5-17-year-old Europeans, along with increased wealth. Pacific islanders were also at greater risk, but due to 0-2-year-old cases. Despite recent high measles, mumps, and rubella vaccine immunization coverage, overall population immunity against measles remains ~90% and is lower in people born between 1982 and 2005. Greatest measles importation risk is during December, and countries predicted to be sources have historical connections and highest travel rates (Australia and UK), followed by Asian countries with high travel rates and higher measles incidences. Our results suggest measles importation due to travel is seeding measles outbreaks, and immunization levels are insufficient to continue to prevent outbreaks because of heterogeneous immunity in the population, leaving particular age groups at risk.

Recent human evolution has shaped geographical differences in susceptibility to disease

PubMed Central

2011-01-01

Background Searching for associations between genetic variants and complex diseases has been a very active area of research for over two decades. More than 51,000 potential associations have been studied and published, a figure that keeps increasing, especially with the recent explosion of array-based Genome-Wide Association Studies. Even if the number of true associations described so far is high, many of the putative risk variants detected so far have failed to be consistently replicated and are widely considered false positives. Here, we focus on the world-wide patterns of replicability of published association studies. Results We report three main findings. First, contrary to previous results, genes associated to complex diseases present lower degrees of genetic differentiation among human populations than average genome-wide levels. Second, also contrary to previous results, the differences in replicability of disease associated-loci between Europeans and East Asians are highly correlated with genetic differentiation between these populations. Finally, highly replicated genes present increased levels of high-frequency derived alleles in European and Asian populations when compared to African populations. Conclusions Our findings highlight the heterogeneous nature of the genetic etiology of complex disease, confirm the importance of the recent evolutionary history of our species in current patterns of disease susceptibility and could cast doubts on the status as false positives of some associations that have failed to replicate across populations. PMID:21261943

Time Trends of High Blood Pressure Prevalence, Awareness and Control in the Italian General Population : Surveys of the National Institute of Health.

PubMed

Di Lonardo, Anna; Donfrancesco, Chiara; Palmieri, Luigi; Vanuzzo, Diego; Giampaoli, Simona

2017-06-01

High blood pressure (BP) is a major risk factor for cardiovascular disease. The urgency of the problem was underlined by the World Health Organization (WHO) Global Action Plan for the prevention and control of noncommunicable diseases, which recommends a 25% relative reduction in the prevalence of raised BP by 2020. A surveillance system represents a useful tool to monitor BP in the general population. Since 1980s, the National Institute of Health has conducted several surveys of the adult general population, measuring cardiovascular risk factors by standardized procedures and methods. To describe mean BP levels and high BP prevalence from 1978 to 2012 by sex and quinquennia of age. Data were derived from the following three studies: (i) Risk Factors and Life Expectancy (RIFLE), conducted between 1978 and 2002 in 13 Italian regions (>70,000 persons); (ii) Osservatorio Epidemiologico Cardiovascolare (OEC), conducted between 1998-2002 in the general population from all Italian regions (>9000 persons); and (iii) Osservatorio Epidemiologico Cardiovascolare/Health Examination Survey (OEC/HES), conducted between 2008-2012 in the general population from all Italian regions (>9000 persons). A significant decrease in mean systolic and diastolic BP levels and prevalence of high BP from 1978 to 2012 was observed both in men and women. BP and high BP increased by age classes in all considered periods. BP awareness and control also improved. Our data suggest that BP control could be achieved by 2020, as recommended by WHO.

Extensive genetic differentiation detected within a model marsupial, the tammar wallaby (Notamacropus eugenii)

PubMed Central

Miller, Emily J.; Neaves, Linda E.; Zenger, Kyall R.; Herbert, Catherine A.

2017-01-01

The tammar wallaby (Notamacropus eugenii) is one of the most intensively studied of all macropodids and was the first Australasian marsupial to have its genome sequenced. However, comparatively little is known about genetic diversity and differentiation amongst the morphologically distinct allopatric populations of tammar wallabies found in Western (WA) and South Australia (SA). Here we compare autosomal and Y-linked microsatellite genotypes, as well as sequence data (~600 bp) from the mitochondrial DNA (mtDNA) control region (CR) in tammar wallabies from across its distribution. Levels of diversity at autosomal microsatellite loci were typically high in the WA mainland and Kangaroo Island (SA) populations (A = 8.9–10.6; He = 0.77–0.78) but significantly reduced in other endemic island populations (A = 3.8–4.1; He = 0.41–0.48). Autosomal and Y-linked microsatellite loci revealed a pattern of significant differentiation amongst populations, especially between SA and WA. The Kangaroo Island and introduced New Zealand population showed limited differentiation. Multiple divergent mtDNA CR haplotypes were identified within both SA and WA populations. The CR haplotypes of tammar wallabies from SA and WA show reciprocal monophyly and are highly divergent (14.5%), with levels of sequence divergence more typical of different species. Within WA tammar wallabies, island populations each have unique clusters of highly related CR haplotypes and each is most closely related to different WA mainland haplotypes. Y-linked microsatellite haplotypes show a similar pattern of divergence although levels of diversity are lower. In light of these differences, we suggest that two subspecies of tammar wallaby be recognized; Notamacropus eugenii eugenii in SA and N. eugenii derbianus in WA. The extensive neutral genetic diversity and inter-population differentiation identified within tammar wallabies should further increase the species value and usefulness as a model organism. PMID:28257440

Unappreciated epidemiology: the churn effect in a regional HIV care programme.

PubMed

Gill, M J; Krentz, H B

2009-08-01

High levels of geographic mobility in and out of HIV care centres (i.e. the churn effect) can disrupt the continuity of patient care, misalign prevention services, impact local prevalence data perturbing optimal allocation of resources, and contribute to logical challenges in repeated transfer of health records. We report on the clinical, demographic, and administrative impact of high population turnover within HIV populations.

Mental illness and a high-risk, elderly Japanese population: characteristic differences related to gender and residential location.

PubMed

Kikuchi, Hiroyuki; Takamiya, Tomoko; Odagiri, Yuko; Ohya, Yumiko; Shimomitsu, Teruichi; Inoue, Shigeru

2013-12-01

Examining the sociodemographic determinants of psychological distress is important in identifying specific subgroups in need of further intervention. However, there are few studies focusing on older populations and on the role of gender or location of residence. To try to clarify characteristics of a population at high risk for mental illness, we examined the sociodemographic determinants of psychological distress in older adults living in three different locations. A mail survey was used to collect data on levels of psychological distress and sociodemographic characteristics from a population-based sample of 1894 older adults who lived in Bunkyo (urban setting), Fuchu (suburban setting) and Oyama (rural setting) in Japan (aged 65-74 years, 51.3% men). Psychological distress level was measured based on Kessler's six-item psychological distress scale (K6) and dichotomized into two groups with a cut-off score of 5 (0-4 or 5-24). Multiple logistic regression analyses were used to examine the associations between sociodemographic factors, specifically gender and location of residence, and psychological distress levels. The variables of older age, living in Bunkyo, living in Oyama and living alone were significantly associated with high psychological distress. Although these associations were observed in men, no associations were observed in women. Location-specific analyses showed significant associations between sociodemographic and psychological distress among men living in Oyama, but not among those in Bunkyo or Fuchu. Sociodemographic factors were significantly correlated with psychological distress, particularly among older men in rural areas. Characteristics of a population at high risk for mental illness may vary based on gender and location of residence. Health promotion initiatives for older adults may be more effective if they take these demographic factors into account. © 2013 The Authors. Psychogeriatrics © 2013 Japanese Psychogeriatric Society.

Mortality of Rocky Mountain elk in Michigan due to meningeal worm.

PubMed

Bender, Louis C; Schmitt, Stephen M; Carlson, Elaine; Haufler, Jonathan B; Beyer, Dean E

2005-01-01

Mortality from cerebrospinal parelaphostrongylosis caused by the meningeal worm (Parelaphostrongylus tenuis) has been hypothesized to limit elk (Cervus elaphus nelsoni) populations in areas where elk are conspecific with white-tailed deer (Odocoileus virginianus). Elk were reintroduced into Michigan (USA) in the early 1900s and subsequently greatly increased population size and distribution despite sympatric high-density (>or=12/km2) white-tailed deer populations. We monitored 100 radio-collared elk of all age and sex classes from 1981-94, during which time we documented 76 mortalities. Meningeal worm was a minor mortality factor for elk in Michigan and accounted for only 3% of mortalities, fewer than legal harvest (58%), illegal kills (22%), other diseases (7%), and malnutrition (4%). Across years, annual cause-specific mortality rates due to cerebrospinal parelaphostrongylosis were 0.033 (SE=0.006), 0.029 (SE=0.005), 0.000 (SE=0.000), and 0.000 (SE=0.000) for calves, 1-yr-old, 2-yr-old, and >or=3-yr-old, respectively. The overall population-level mortality rate due to cerebrospinal parelaphostrongylosis was 0.009 (SE=0.001). Thus, meningeal worm had little impact on elk in Michigan during our study despite greater than normal precipitation (favoring gastropods) and record (>or=14 km2) deer densities. Further, elk in Michigan have shown sustained population rates-of-increase of >or=18%/yr and among the highest levels of juvenile production and survival recorded for elk in North America, indicating that elk can persist in areas with meningeal worm at high levels of population productivity. It is likely that local ecologic characteristics among elk, white-tailed deer, and gastropods, and degree of exposure, age of elk, individual and population experience with meningeal worm, overall population vigor, and moisture determine the effects of meningeal worm on elk populations.

Mortality of rocky mountain elk in Michigan due to meningeal worm

USGS Publications Warehouse

Bender, L.C.; Schmitt, S.M.; Carlson, E.; Haufler, J.B.; Beyer, D.E.

2005-01-01

Mortality from cerebrospinal parelaphostrongylosis caused by the meningeal worm (Parelaphostrongylus tenuis) has been hypothesized to limit elk (Cervus elaphus nelsoni) populations in areas where elk are conspecific with white-tailed deer (Odocoileus virginianus). Elk were reintroduced into Michigan (USA) in the early 1900s and subsequently greatly increased population size and distribution despite sympatric high-density (???12/km2) white-tailed deer populations. We monitored 100 radio-collared elk of all age and sex classes from 1981-94, during which time we documented 76 mortalities. Meningeal worm was a minor mortality factor for elk in Michigan and accounted for only 3% of mortalities, fewer than legal harvest (58%), illegal kills (22%), other diseases (7%), and malnutrition (4%). Across years, annual cause-specific mortality rates due to cerebrospinal parelaphostrongylosis were 0.033 (SE=0.006), 0.029 (SE=0.005), 0.000 (SE=0.001), and 0.000 (SE=0.000) for calves, 1-yr-old, 2-yr-old, and ???3-yr-old, respectively. The overall population-level mortality rate due to cerebrospinal parelaphostrongylosis was 0.009 (SE=0.001). Thus, meningeal worm had little impact on elk in Michigan during our study despite greater than normal precipitation (favoring gastropods) and record (???14 km2) deer densities. Further, elk in Michigan have shown sustained population rates-of-increase of ???18%/yr and among the highest levels of juvenile production and survival recorded for elk in North America, indicating that elk can persist in areas with meningeal worm at high levels of population productivity. it is likely that local ecologic characteristics among elk, white-tailed deer, and gastropods, and degree of exposure, age of elk, individual and population experience with meningeal worm, overall population vigor, and moisture determine the effects of meningeal worm on elk populations. ?? Wildlife Disease Association 2005.

Contact-dependent growth inhibition induces high levels of antibiotic-tolerant persister cells in clonal bacterial populations.

PubMed

Ghosh, Anirban; Baltekin, Özden; Wäneskog, Marcus; Elkhalifa, Dina; Hammarlöf, Disa L; Elf, Johan; Koskiniemi, Sanna

2018-05-02

Bacterial populations can use bet-hedging strategies to cope with rapidly changing environments. One example is non-growing cells in clonal bacterial populations that are able to persist antibiotic treatment. Previous studies suggest that persisters arise in bacterial populations either stochastically through variation in levels of global signalling molecules between individual cells, or in response to various stresses. Here, we show that toxins used in contact-dependent growth inhibition (CDI) create persisters upon direct contact with cells lacking sufficient levels of CdiI immunity protein, which would otherwise bind to and neutralize toxin activity. CDI-mediated persisters form through a feedforward cycle where the toxic activity of the CdiA toxin increases cellular (p)ppGpp levels, which results in Lon-mediated degradation of the immunity protein and more free toxin. Thus, CDI systems mediate a population density-dependent bet-hedging strategy, where the fraction of non-growing cells is increased only when there are many cells of the same genotype. This may be one of the mechanisms of how CDI systems increase the fitness of their hosts. © 2018 The Authors.

Research on Grid Size Suitability of Gridded Population Distribution in Urban Area: A Case Study in Urban Area of Xuanzhou District, China.

PubMed

Dong, Nan; Yang, Xiaohuan; Cai, Hongyan; Xu, Fengjiao

2017-01-01

The research on the grid size suitability is important to provide improvement in accuracies of gridded population distribution. It contributes to reveal the actual spatial distribution of population. However, currently little research has been done in this area. Many well-modeled gridded population dataset are basically built at a single grid scale. If the grid cell size is not appropriate, it will result in spatial information loss or data redundancy. Therefore, in order to capture the desired spatial variation of population within the area of interest, it is necessary to conduct research on grid size suitability. This study summarized three expressed levels to analyze grid size suitability, which include location expressed level, numeric information expressed level, and spatial relationship expressed level. This study elaborated the reasons for choosing the five indexes to explore expression suitability. These five indexes are consistency measure, shape index rate, standard deviation of population density, patches diversity index, and the average local variance. The suitable grid size was determined by constructing grid size-indicator value curves and suitable grid size scheme. Results revealed that the three expressed levels on 10m grid scale are satisfying. And the population distribution raster data with 10m grid size provide excellent accuracy without loss. The 10m grid size is recommended as the appropriate scale for generating a high-quality gridded population distribution in our study area. Based on this preliminary study, it indicates the five indexes are coordinated with each other and reasonable and effective to assess grid size suitability. We also suggest choosing these five indexes in three perspectives of expressed level to carry out the research on grid size suitability of gridded population distribution.

Research on Grid Size Suitability of Gridded Population Distribution in Urban Area: A Case Study in Urban Area of Xuanzhou District, China

PubMed Central

Dong, Nan; Yang, Xiaohuan; Cai, Hongyan; Xu, Fengjiao

2017-01-01

The research on the grid size suitability is important to provide improvement in accuracies of gridded population distribution. It contributes to reveal the actual spatial distribution of population. However, currently little research has been done in this area. Many well-modeled gridded population dataset are basically built at a single grid scale. If the grid cell size is not appropriate, it will result in spatial information loss or data redundancy. Therefore, in order to capture the desired spatial variation of population within the area of interest, it is necessary to conduct research on grid size suitability. This study summarized three expressed levels to analyze grid size suitability, which include location expressed level, numeric information expressed level, and spatial relationship expressed level. This study elaborated the reasons for choosing the five indexes to explore expression suitability. These five indexes are consistency measure, shape index rate, standard deviation of population density, patches diversity index, and the average local variance. The suitable grid size was determined by constructing grid size-indicator value curves and suitable grid size scheme. Results revealed that the three expressed levels on 10m grid scale are satisfying. And the population distribution raster data with 10m grid size provide excellent accuracy without loss. The 10m grid size is recommended as the appropriate scale for generating a high-quality gridded population distribution in our study area. Based on this preliminary study, it indicates the five indexes are coordinated with each other and reasonable and effective to assess grid size suitability. We also suggest choosing these five indexes in three perspectives of expressed level to carry out the research on grid size suitability of gridded population distribution. PMID:28122050

Population structure of Angiostrongylus cantonensis (Nematoda: Metastrongylidae) in Thailand based on PCR-RAPD markers.

PubMed

Thaenkham, Urusa; Pakdee, Wallop; Nuamtanong, Supaporn; Maipanich, Wanna; Pubampen, Somchit; Sa-Nguankiat, Surapol; Komalamisra, Chalit

2012-05-01

Angiostrongylus cantonensis is the causative agent of angiostrongyliasis, which is widely distributed throughout the world. It can specifically infect many species of intermediate and definitive hosts. This study examined the genetic differentiation and population structure using the RAPD-PCR method of parasites obtained from 8 different geographical areas of Thailand. Based on 8 primers, high levels of genetic diversity and low levels of gene flow among populations were found. Using genetic distance and neighbor-joining dendrogram methods, A. cantonensis in Thailand could be divided into two groups with statistically significant genetic differentiation of the two populations. However, genotypic variations and haplotype relationships need to be further elucidated using other markers.

Genetic variation in laboratory and field populations of the vector of bluetongue virus, Culicoides variipennis (Diptera: Ceratopogonidae).

PubMed

Tabachnick, W J

1990-01-01

Laboratory colonies and several natural populations of the biting midge Culicoides variipennis (Coquillett) were analyzed for genetic variation at 21 electrophoretic loci. The laboratory colonies maintained high levels of genetic variation measured by average expected heterozygosities (He = 0.142 +/- 0.008), although levels were lower than those observed in field collections (He = 0.198 +/- 0.009). A field population from Colorado, analyzed five times over a 1-yr period, showed a consistent trend in the change in gene frequencies at two loci. Genetic comparisons between natural populations were consistent with the existence of two subspecies. C. variipennis variipennis and C. variipennis sonorensis Wirth & Jones.

The Evolution of Human Genetic and Phenotypic Variation in Africa

PubMed Central

Campbell, Michael C.

2010-01-01

Africa is the birthplace of modern humans, and is the source of the geographic expansion of ancestral populations into other regions of the world. Indigenous Africans are characterized by high levels of genetic diversity within and between populations. The pattern of genetic variation in these populations has been shaped by demographic events occurring over the last 200,000 years. The dramatic variation in climate, diet, and exposure to infectious disease across the continent has also resulted in novel genetic and phenotypic adaptations in extant Africans. This review summarizes some recent advances in our understanding of the demographic history and selective pressures that have influenced levels and patterns of diversity in African populations. PMID:20178763

Population Genetic Structure of the Tropical Two-Wing Flyingfish (Exocoetus volitans)

PubMed Central

Lewallen, Eric A.; Bohonak, Andrew J.; Bonin, Carolina A.; van Wijnen, Andre J.; Pitman, Robert L.; Lovejoy, Nathan R.

2016-01-01

Delineating populations of pantropical marine fish is a difficult process, due to widespread geographic ranges and complex life history traits in most species. Exocoetus volitans, a species of two-winged flyingfish, is a good model for understanding large-scale patterns of epipelagic fish population structure because it has a circumtropical geographic range and completes its entire life cycle in the epipelagic zone. Buoyant pelagic eggs should dictate high local dispersal capacity in this species, although a brief larval phase, small body size, and short lifespan may limit the dispersal of individuals over large spatial scales. Based on these biological features, we hypothesized that E. volitans would exhibit statistically and biologically significant population structure defined by recognized oceanographic barriers. We tested this hypothesis by analyzing cytochrome b mtDNA sequence data (1106 bps) from specimens collected in the Pacific, Atlantic and Indian oceans (n = 266). AMOVA, Bayesian, and coalescent analytical approaches were used to assess and interpret population-level genetic variability. A parsimony-based haplotype network did not reveal population subdivision among ocean basins, but AMOVA revealed limited, statistically significant population structure between the Pacific and Atlantic Oceans (ΦST = 0.035, p<0.001). A spatially-unbiased Bayesian approach identified two circumtropical population clusters north and south of the Equator (ΦST = 0.026, p<0.001), a previously unknown dispersal barrier for an epipelagic fish. Bayesian demographic modeling suggested the effective population size of this species increased by at least an order of magnitude ~150,000 years ago, to more than 1 billion individuals currently. Thus, high levels of genetic similarity observed in E. volitans can be explained by high rates of gene flow, a dramatic and recent population expansion, as well as extensive and consistent dispersal throughout the geographic range of the species. PMID:27736863

Population Genetic Structure of the Tropical Two-Wing Flyingfish (Exocoetus volitans).

PubMed

Lewallen, Eric A; Bohonak, Andrew J; Bonin, Carolina A; van Wijnen, Andre J; Pitman, Robert L; Lovejoy, Nathan R

2016-01-01

Delineating populations of pantropical marine fish is a difficult process, due to widespread geographic ranges and complex life history traits in most species. Exocoetus volitans, a species of two-winged flyingfish, is a good model for understanding large-scale patterns of epipelagic fish population structure because it has a circumtropical geographic range and completes its entire life cycle in the epipelagic zone. Buoyant pelagic eggs should dictate high local dispersal capacity in this species, although a brief larval phase, small body size, and short lifespan may limit the dispersal of individuals over large spatial scales. Based on these biological features, we hypothesized that E. volitans would exhibit statistically and biologically significant population structure defined by recognized oceanographic barriers. We tested this hypothesis by analyzing cytochrome b mtDNA sequence data (1106 bps) from specimens collected in the Pacific, Atlantic and Indian oceans (n = 266). AMOVA, Bayesian, and coalescent analytical approaches were used to assess and interpret population-level genetic variability. A parsimony-based haplotype network did not reveal population subdivision among ocean basins, but AMOVA revealed limited, statistically significant population structure between the Pacific and Atlantic Oceans (ΦST = 0.035, p<0.001). A spatially-unbiased Bayesian approach identified two circumtropical population clusters north and south of the Equator (ΦST = 0.026, p<0.001), a previously unknown dispersal barrier for an epipelagic fish. Bayesian demographic modeling suggested the effective population size of this species increased by at least an order of magnitude ~150,000 years ago, to more than 1 billion individuals currently. Thus, high levels of genetic similarity observed in E. volitans can be explained by high rates of gene flow, a dramatic and recent population expansion, as well as extensive and consistent dispersal throughout the geographic range of the species.

Population Genetic Analysis of Theileria annulata from Six Geographical Regions in China, Determined on the Basis of Micro- and Mini-satellite Markers

PubMed Central

Yin, Fangyuan; Liu, Zhijie; Liu, Junlong; Liu, Aihong; Salih, Diaeldin A.; Li, Youquan; Liu, Guangyuan; Luo, Jianxun; Guan, Guiquan; Yin, Hong

2018-01-01

Theileria annulata, a tick-borne apicomplexan protozoan, causes a lymphoproliferative disease of cattle with high prevalence in tropical and sub-tropical regions. Understanding the genetic diversity and structure of local populations will provide more fundamental knowledge for the population genetics and epidemics of protozoa. In this study, 78 samples of T. annulata collected from cattle/yaks representing 6 different geographic populations in China were genotyped using eight micro- and mini-satellite markers. High genetic variation within population, moderate genetic differentiation, and high level of diversity co-occurring with significant linkage disequilibrium were observed, which indicates there is gene flow between these populations in spite of the existence of reproductive and geographical barriers among populations. Furthermore, some degree of genetic differentiation was also found between samples from China and Oman. These findings provide a first glimpse of the genetic diversity of the T. annulata populations in China, and might contribute to the knowledge of distribution, dynamics, and epidemiology of T. annulata populations and optimize the management strategies for control. PMID:29515624

Zn-71 levels populated in neutron-capture-gamma reactions

NASA Astrophysics Data System (ADS)

Huchison, Andrew; Harker, Jessica; Walters, William B.; Waite, Mark; Paul, Rick

2015-04-01

The level structure of 71 Zn was studied via the capture-gamma reaction on a highly-enriched 70 Zn target at the NIST Center for Neutron Research NG-7 beam line. The neutron separation energy was determined to be 5832.5(5) keV. Low-spin levels populated in this reaction will be presented, compared with data from other measurements, and discussed. This material is based on work supported by the US Department of Energy (DOE), Office of Science, Office of Nuclear Physics, under Grant No. DE-FG02-94ER40834.

Bayesian Small Area Estimates of Diabetes Incidence by United States County, 2009

PubMed Central

Barker, Lawrence E.; Thompson, Theodore J.; Kirtland, Karen A; Boyle, James P; Geiss, Linda S; McCauley, Mary M.; Albright, Ann L.

2015-01-01

In the United States, diabetes is common and costly. Programs to prevent new cases of diabetes are often carried out at the level of the county, a unit of local government. Thus, efficient targeting of such programs requires county-level estimates of diabetes incidence–the fraction of the non-diabetic population who received their diagnosis of diabetes during the past 12 months. Previously, only estimates of prevalence–the overall fraction of population who have the disease–have been available at the county level. Counties with high prevalence might or might not be the same as counties with high incidence, due to spatial variation in mortality and relocation of persons with incident diabetes to another county. Existing methods cannot be used to estimate county-level diabetes incidence, because the fraction of the population who receive a diabetes diagnosis in any year is too small. Here, we extend previously developed methods of Bayesian small-area estimation of prevalence, using diffuse priors, to estimate diabetes incidence for all U.S. counties based on data from a survey designed to yield state-level estimates. We found high incidence in the southeastern United States, the Appalachian region, and in scattered counties throughout the western U.S. Our methods might be applicable in other circumstances in which all cases of a rare condition also must be cases of a more common condition (in this analysis, “newly diagnosed cases of diabetes” and “cases of diabetes”). If appropriate data are available, our methods can be used to estimate proportion of the population with the rare condition at greater geographic specificity than the data source was designed to provide. PMID:26279666

Unhealthy Behaviours: An International Comparison.

PubMed

Ferretti, Fabrizio

2015-01-01

In the current global economy, chronic non-communicable diseases (NCDs) have become the leading cause of death and a major health concern for both developed and developing countries. Among other factors, the worldwide spread of NCDs is driven by the globalisation of unhealthy habits. The purpose of this paper is to develop a simple statistic to measure, at the national level, the average population's exposure to the main NCDs modifiable risk factors. The approach and methodology followed by the United Nations Development Programme to compute the Human Development Index (HDI) is applied to four basic indicators of NCD-related preventable risk factors (alcohol consumption, excess caloric intake, non-balanced diet and tobacco use) in 112 countries worldwide in 2012-14. We obtain a summary composite index, which we call the Unhealthy Behaviour Index (UBI), which ranks countries by the average level of the unhealthy habits (drinking, eating and smoking) of their populations. We find that Belarus and Russian federation are the two countries with the unhealthiest NCD-related lifestyle. With the exception of Canada, the first twenty populations more exposed to the main NCDs preventable risk factors all live in European countries, and mainly in countries of Eastern Europe. Overall, the UBI tends to increase along with the level of human development. In medium, high and very high HDI countries, however, the same level of human development may be associated with very different kinds of NCD-related lifestyles. Finally, economic growth may push populations toward either more unhealthy or healthy habits, depending on the countries' level of development; the elasticity of unhealthy habits with respect to income per capita is positive (but less than one: on average 0.6) until $30,000, decreases as income rises, and becomes negative (around -0.3) in very high income countries.

Air pollution exposure: Who is at high risk?

NASA Astrophysics Data System (ADS)

Peled, Ronit

2011-04-01

This article reviews the sub-population groups who are at high risk and first to be harmed by air pollution coming from anthropogenic combustions. Epidemiological studies from the last few decades contributed to the understanding of the different levels of susceptibility to air pollution. Older people and young infants, people who suffer from allergies, pulmonary and heart diseases, pregnant women and newborn babies, and deprived populations that suffer from low socio-economic status have all been described as populations at risk. A better understanding of the role of air pollution on large as well as specific populations' health, will promote a better protection policy.

Challenges to assessing connectivity between massive populations of the Australian plague locust

PubMed Central

Chapuis, Marie-Pierre; Popple, Julie-Anne M.; Berthier, Karine; Simpson, Stephen J.; Deveson, Edward; Spurgin, Peter; Steinbauer, Martin J.; Sword, Gregory A.

2011-01-01

Linking demographic and genetic dispersal measures is of fundamental importance for movement ecology and evolution. However, such integration can be difficult, particularly for highly fecund species that are often the target of management decisions guided by an understanding of population movement. Here, we present an example of how the influence of large population sizes can preclude genetic approaches from assessing demographic population structuring, even at a continental scale. The Australian plague locust, Chortoicetes terminifera, is a significant pest, with populations on the eastern and western sides of Australia having been monitored and managed independently to date. We used microsatellites to assess genetic variation in 12 C. terminifera population samples separated by up to 3000 km. Traditional summary statistics indicated high levels of genetic diversity and a surprising lack of population structure across the entire range. An approximate Bayesian computation treatment indicated that levels of genetic diversity in C. terminifera corresponded to effective population sizes conservatively composed of tens of thousands to several million individuals. We used these estimates and computer simulations to estimate the minimum rate of dispersal, m, that could account for the observed range-wide genetic homogeneity. The rate of dispersal between both sides of the Australian continent could be several orders of magnitude lower than that typically considered as required for the demographic connectivity of populations. PMID:21389030

Population-structure and genetic diversity in a haplochromine cichlid fish [corrected] of a satellite lake of Lake Victoria.

PubMed

Abila, Romulus; Barluenga, Marta; Engelken, Johannes; Meyer, Axel; Salzburger, Walter

2004-09-01

The approximately 500 species of the cichlid fish species flock of Lake Victoria, East Africa, have evolved in a record-setting 100,000 years and represent one of the largest adaptive radiations. We examined the population structure of the endangered cichlid species Xystichromis phytophagus from Lake Kanyaboli, a satellite lake to Lake Victoria in the Kenyan Yala wetlands. Two sets of molecular markers were analysed--sequences of the mitochondrial control region as well as six microsatellite loci--and revealed surprisingly high levels of genetic variability in this species. Mitochondrial DNA sequences failed to detect population structuring among the three sample populations. A model-based population assignment test based on microsatellite data revealed that the three populations most probably aggregate into a larger panmictic population. However, values of population pairwise FST indicated moderate levels of genetic differentiation for one population. Eleven distinct mitochondrial haplotypes were found among 205 specimens of X. phytophagus, a relatively high number compared to the total number of 54 haplotypes that were recovered from hundreds of specimens of the entire cichlid species flock of Lake Victoria. Most of the X. phytophagus mitochondrial DNA haplotypes were absent from the main Lake Victoria, corroborating the putative importance of satellite lakes as refugia for haplochromine cichlids that went extinct from the main lake in the last decades and possibly during the Late Pleistocene desiccation of Lake Victoria.

The genealogy and genetic viability of reintroduced Yellowstone grey wolves.

PubMed

Vonholdt, Bridgett M; Stahler, Daniel R; Smith, Douglas W; Earl, Dent A; Pollinger, John P; Wayne, Robert K

2008-01-01

The recovery of the grey wolf in Yellowstone National Park is an outstanding example of a successful reintroduction. A general question concerning reintroduction is the degree to which genetic variation has been preserved and the specific behavioural mechanisms that enhance the preservation of genetic diversity and reduce inbreeding. We have analysed 200 Yellowstone wolves, including all 31 founders, for variation in 26 microsatellite loci over the 10-year reintroduction period (1995-2004). The population maintained high levels of variation (1995 H(0) = 0.69; 2004 H(0) = 0.73) with low levels of inbreeding (1995 F(IS) = -0.063; 2004 F(IS) = -0.051) and throughout, the population expanded rapidly (N(1995) = 21; N(2004) = 169). Pedigree-based effective population size ratios did not vary appreciably over the duration of population expansion (1995 N(e)/N(g) = 0.29; 2000 N(e)/N(g) = 0.26; 2004 N(e)/N(g) = 0.33). We estimated kinship and found only two of 30 natural breeding pairs showed evidence of being related (average r = -0.026, SE = 0.03). We reconstructed the genealogy of 200 wolves based on genetic and field data and discovered that they avoid inbreeding through a wide variety of behavioural mechanisms including absolute avoidance of breeding with related pack members, male-biased dispersal to packs where they breed with nonrelatives, and female-biased subordinate breeding. We documented a greater diversity of such population assembly patterns in Yellowstone than previously observed in any other natural wolf population. Inbreeding avoidance is nearly absolute despite the high probability of within-pack inbreeding opportunities and extensive interpack kinship ties between adjacent packs. Simulations showed that the Yellowstone population has levels of genetic variation similar to that of a population managed for high variation and low inbreeding, and greater than that expected for random breeding within packs or across the entire breeding pool. Although short-term losses in variation seem minimal, future projections of the population at carrying capacity suggest significant inbreeding depression will occur without connectivity and migratory exchange with other populations.

Serosal Cavities Contain Two Populations of Innate-like integrin α4highCD4+ T Cells, Integrin α4β1+α6β1+α4β7- and α4β1+α6β1-α4β7+ Cells.

PubMed

Yang, Jeong In; Park, Chanho; Kho, Inseong; Lee, Sujin; Suh, Kyung-Suk; Kim, Tae Jin

2017-12-01

We previously reported peritoneal innate-like integrin α4 (CD49d) high CD4 + T cells that provided help for B-1a cells. Here we analyzed the expression of various integrin chains on the peritoneal and pleural integrin α4 high CD4 + T cells and investigated the functional heterogeneity of the subpopulations based on the integrin expression. Pleural cavity contained a lower ratio of integrin α4 high CD4 + T cells to integrin α4 low CD4 + T cells than peritoneal cavity, but the pleural integrin α4 high CD4 + T cells have the same characteristics of the peritoneal integrin α4 high CD4 + T cells. Most of integrin α4 high CD4 + T cells were integrin β1 high β7 - , but a minor population of integrin α4 high CD4 + T cells was integrin β1 + β7 + . Interestingly, the integrin α4 high β1 high β7 - CD4 + T cells expressed high levels of integrin α4β1 and α6β1, whereas integrin α4 high β1 + β7 + CD4 + T cells expressed high levels of integrin α4β1 and α4β7, suggesting an alternative expression of integrin α6β1 or α4β7 in combination with α4β1 in respective major and minor populations of integrin α4 high CD4 + T cells. The minor population, integrin α4 high β1 + β7 + CD4 + T cells, were different from the integrin α4 high β1 high β7 - CD4 + T cells in that they secreted a smaller amount of Th1 cytokines upon stimulation and expressed lower levels of Th1-related chemokine receptors CCR5 and CXCR3 than the integrin α4 high β 1 high β 7 - CD4 + T cells. In summary, the innate-like integrin α4 high CD4 + T cells could be divided into 2 populations, integrin α4β1 + α6β1 + α4β7 - and α4β1 + α6β1 - α4β7 + cells. The functional significance of serosal integrin α4β7 + CD4 + T cells needed to be investigated especially in view of mucosal immunity.

[Obesity and leptin association in three Chilean aboriginal populations].

PubMed

Pérez, F; Santos, J L; Albala, C; Calvillán, M; Carrasco, E

2000-01-01

Although there is a clear relationship between body mass index and leptin levels, few authors have addressed the possible influence of ethnic factors on these levels. To measure serum leptin in three different Chilean aboriginal populations. Fasting serum leptin and insulin levels were measured by radioimmunoassay in 345 rural mapuche individuals, 247 rural aymara subjects and 162 urban mapuche subjects. A body mass index of 27.5 kg/m2 was used as cutoff point to classify study subjects. Among the three ethnic groups, women had serum leptin levels three times higher than men. In all three ethnic groups, there was a significant association between leptin levels, body mass index and gender (r2 = 0.32 and 0.5 p < 0.001, in rural mapuche, r2 = 0.32 and 0.5 p < 0.001, in aymara and r2 = 0.24 and 0.49, p < 0.001 in urban mapuche populations). No differences in leptin levels were observed for the interaction between age and insulin. The increments per quartile in leptin levels were lower among mapuche than aymara individuals. Rural mapuche individuals have a high frequency of obesity. However their leptin levels are lower than those of aymara or urban mapuche populations. The higher leptin levels observed in urban mapuche subjects could be due to environmental influences.

Mitochondrial DNA markers reveal high genetic diversity but low genetic differentiation in the black fly Simulium tani Takaoka & Davies along an elevational gradient in Malaysia.

PubMed

Low, Van Lun; Adler, Peter H; Takaoka, Hiroyuki; Ya'cob, Zubaidah; Lim, Phaik Eem; Tan, Tiong Kai; Lim, Yvonne A L; Chen, Chee Dhang; Norma-Rashid, Yusoff; Sofian-Azirun, Mohd

2014-01-01

The population genetic structure of Simulium tani was inferred from mitochondria-encoded sequences of cytochrome c oxidase subunits I (COI) and II (COII) along an elevational gradient in Cameron Highlands, Malaysia. A statistical parsimony network of 71 individuals revealed 71 haplotypes in the COI gene and 43 haplotypes in the COII gene; the concatenated sequences of the COI and COII genes revealed 71 haplotypes. High levels of genetic diversity but low levels of genetic differentiation were observed among populations of S. tani at five elevations. The degree of genetic diversity, however, was not in accordance with an altitudinal gradient, and a Mantel test indicated that elevation did not have a limiting effect on gene flow. No ancestral haplotype of S. tani was found among the populations. Pupae with unique structural characters at the highest elevation showed a tendency to form their own haplotype cluster, as revealed by the COII gene. Tajima's D, Fu's Fs, and mismatch distribution tests revealed population expansion of S. tani in Cameron Highlands. A strong correlation was found between nucleotide diversity and the levels of dissolved oxygen in the streams where S. tani was collected.

Trace metals in the hair of habitants of the Ok Tedi region, Papua New Guinea.

PubMed

Jones, G L; Willy, D; Lumsden, B; Taufa, T; Lourie, J

1987-01-01

It has long been known that mining activity can markedly change the level and distribution of certain heavy metals in the adjacent environment. This pollution can be quite widespread and long lasting and often has deleterious effects on the health of local populations. In the present study scalp hair was used as the biopsy material because of its ease of collection and long history of use in this connection. Hair was collected from all the local villages in the vicinity of the mine site, as well as from Papua New Guinean nationals from other provinces, and European expatriates who were employed by the mining company and who were resident in the area. Hair from local people showed a remarkably high iron content by comparison with previously studied populations. The extreme variations in hair iron levels were reflected in the differential distribution of levels according to location, age and sex. Hair cadmium was also high in the population studied. Hair copper, lead, zinc and mercury all appeared to be within 'normal' limits by comparison with other general populations. These results are discussed in the context of the environmental and social impact of the mining operations on the local people.

Two independent apolipoprotein A5 haplotypes influence human plasma triglyceride levels.

PubMed

Pennacchio, Len A; Olivier, Michael; Hubacek, Jaroslav A; Krauss, Ronald M; Rubin, Edward M; Cohen, Jonathan C

2002-11-15

The recently identified apolipoprotein A5 gene (APOA5) has been shown to play an important role in determining plasma triglyceride concentrations in humans and mice. We previously identified an APOA5 haplotype (designated APOA5*2) that is present in approximately 16% of Caucasians and is associated with increased plasma triglyceride concentrations. In this report we describe another APOA5 haplotype (APOA5*3) containing the rare allele of the single nucleotide polymorphism c.56C>G that changes serine to tryptophan at codon 19 and is independently associated with high plasma triglyceride levels in three different populations. In a sample of 264 Caucasian men and women with plasma triglyceride concentrations above the 90th percentile or below the 10th percentile, the APOA5*3 haplotype was more than three-fold more common in the group with high plasma triglyceride levels. In a second independently ascertained sample of Caucasian men and women (n=419) who were studied while consuming their self-selected diets as well as after high-carbohydrate diets and high-fat diets, the APOA5*3 haplotype was associated with increased plasma triglyceride levels on all three dietary regimens. In a third population comprising 2660 randomly selected individuals, the APOA5*3 haplotype was found in 12% of Caucasians, 14% of African-Americans and 28% of Hispanics and was associated with increased plasma triglyceride levels in both men and women in each ethnic group. These findings establish that the APOA5 locus contributes significantly to inter-individual variation in plasma triglyceride levels in humans. Together, the APOA5*2 and APOA5*3 haplotypes are found in 25-50% of African-Americans, Hispanics and Caucasians and support the contribution of common human variation to quantitative phenotypes in the general population.

Association of neighbourhood unemployment rate with incident Type 2 diabetes mellitus in five German regions.

PubMed

Müller, G; Wellmann, J; Hartwig, S; Greiser, K H; Moebus, S; Jöckel, K-H; Schipf, S; Völzke, H; Maier, W; Meisinger, C; Tamayo, T; Rathmann, W; Berger, K

2015-08-01

To analyse the association of neighbourhood unemployment with incident self-reported physician-diagnosed Type 2 diabetes in a population aged 45-74 years from five German regions. Study participants were linked via their addresses at baseline to particular neighbourhoods. Individual-level data from five population-based studies were pooled and combined with contextual data on neighbourhood unemployment. Type 2 diabetes was assessed according to a self-reported physician diagnosis of diabetes. We estimated proportional hazard models (Weibull distribution) in order to obtain hazard ratios and 95% CIs of Type 2 diabetes mellitus, taking into account interval-censoring and clustering. We included 7250 participants residing in 228 inner city neighbourhoods in five German regions in our analysis. The incidence rate was 12.6 per 1000 person-years (95% CI 11.4-13.8). The risk of Type 2 diabetes mellitus was higher in men [hazard ratio 1.79 (95% CI 1.47-2.18)] than in women and higher in people with a low education level [hazard ratio 1.55 (95% CI 1.18-2.02)] than in those with a high education level. Independently of individual-level characteristics, we found a higher risk of Type 2 diabetes mellitus in neighbourhoods with high levels of unemployment [quintile 5; hazard ratio 1.72 (95% CI 1.23-2.42)] than in neighbourhoods with low unemployment (quintile 1). Low education level and high neighbourhood unemployment were independently associated with an elevated risk of Type 2 diabetes mellitus. Studies examining the impact of the residential environment on Type 2 diabetes mellitus will provide knowledge that is essential for the identification of high-risk populations. © 2014 The Authors. Diabetic Medicine © 2014 Diabetes UK.

Quantifying the effect of changes in state-level adult smoking rates on youth smoking.

PubMed

Farrelly, Matthew C; Arnold, Kristin Y; Juster, Harlan R; Allen, Jane A

2014-01-01

Quantify the degree to which changes in state-level adult smoking prevalence subsequently influence youth smoking prevalence. Analysis of data from the Tobacco Use Supplement to the Current Population Survey (TUS-CPS) collected from 1995 to 2006 and the National Youth Tobacco Survey (NYTS) collected from 1999 to 2006. Adults 25 years or older who completed the TUS-CPS and youth in middle and high school who completed the NYTS. Current smoking among middle and high school students as a function of the change in state-level adult smoking, controlling for individual-level sociodemographic characteristics and state-level tobacco control policy variables. Among middle school students, declines in state-level adult smoking rates are associated with lower odds of current smoking (P < .05), and each doubling of the decline in adult smoking rates is associated with a 6.0% decrease in youth smoking. Among high school students, declines in state-level adult smoking rates are not associated with current smoking. Higher cigarette prices were associated with lower odds of smoking among middle and high school students. Greater population coverage by smoke-free air laws and greater funding for tobacco control programs were associated with lower odds of current smoking among high school students but not middle school students. Compliance with youth access laws was not associated with middle or high school smoking. By quantifying the effect of changes in state-level adult smoking rates on youth smoking, this study enhances the precision with which the tobacco control community can assess the return on investment for adult-focused tobacco control programs.

Quantitative trait loci for maysin synthesis in maize (Zea mays L.) lines selected for high silk maysin content.

PubMed

Meyer, J D F; Snook, M E; Houchins, K E; Rector, B G; Widstrom, N W; McMullen, M D

2007-06-01

Maysin is a naturally occurring C-glycosyl flavone found in maize (Zea mays L.) silk tissue that confers resistance to corn earworm (Helicoverpa zea, Boddie). Recently, two new maize populations were derived for high silk maysin. The two populations were named the exotic populations of maize (EPM) and the southern inbreds of maize (SIM). Quantitative trait locus (QTL) analysis was employed to determine which loci were responsible for elevated maysin levels in inbred lines derived from the EPM and SIM populations. The candidate genes consistent with QTL position included the p (pericarp color), c2 (colorless2), whp1 (white pollen1) and in1 (intensifier1) loci. The role of these loci in controlling high maysin levels in silks was tested by expression analysis and use of the loci as genetic markers onto the QTL populations. These studies support p, c2 and whp1, but not in1, as loci controlling maysin. Through this study, we determined that the p locus regulates whp1 transcription and that increased maysin in these inbred lines was primarily due to alleles at both structural and regulatory loci promoting increased flux through the flavone pathway by increasing chalcone synthase activity.

Experimental Shigella Infections in Laboratory Animals I. Antagonism by Human Normal Flora Components in Gnotobiotic Mice 12

PubMed Central

Maier, Bruce R.; Hentges, David J.

1972-01-01

Germfree mice were associated with selected species of human intestinal bacteria and then challenged with a streptomycin-resistant Shigella flexneri strain. Antagonism against Shigella was most pronounced in mice associated with Escherichia coli and least pronounced in mice associated with Bacteroides fragilis. A moderate degree of antagonism could be demonstrated in mice associated with either Streptococcus faecalis or Bifidobacterium adolescentis. Shigella persisted in the cecal contents of E. coli-associated mice at very low, stable levels. Shigella populations were reduced to levels below detection in the ceca of mice diassociated with E. coli and Bacteroides. Upon subsequent administration of streptomycin, Bacteroides disappeared from the ceca. The E. coli population was greatly reduced, and Shigella reappeared at very high population levels as an apparent recombinant which resembled E. coli biochemically. A streptomycin-resistant E. coli population subsequently emerged and became dominant in the ceca. Shigella concomitantly declined to levels below detection. PMID:4631914

Distinctive role of income in the all-cause mortality among working age migrants and the settled population in Finland: A follow-up study from 2001 to 2014.

PubMed

Patel, Kishan; Kouvonen, Anne; Koskinen, Aki; Kokkinen, Lauri; Donnelly, Michael; O'Reilly, Dermot; Vaananen, Ari

2018-03-01

Although income level may play a significant part in mortality among migrants, previous research has not focused on the relationship between income, migration and mortality risk. The aim of this register study was to compare all-cause mortality by income level between different migrant groups and the majority settled population of Finland. A random sample was drawn of 1,058,391 working age people (age range 18-64 years; 50.4% men) living in Finland in 2000 and linked to mortality data from 2001 to 2014. The data were obtained from Statistics Finland. Cox proportional hazards models were used to investigate the association between region of origin and all-cause mortality in low- and high-income groups. The risk for all-cause mortality was significantly lower among migrants than among the settled majority population (hazards ratio (HR) 0.57; 95% confidence interval (CI) 0.53-0.62). After adjustment for age, sex, marital status, employment status and personal income, the risk of mortality was significantly reduced for low-income migrants compared with the settled majority population with a low income level (HR 0.46; 95% CI 0.42-0.50) and for high-income migrants compared with the high-income settled majority (HR 0.81; 95% CI 0.69-0.95). Results comparing individual high-income migrant groups and the settled population were not significant. Low-income migrants from Africa, the Middle East and Asia had the lowest mortality risk of any migrant group studied (HR 0.32; 95% CI 0.27-0.39). Particularly low-income migrants seem to display a survival advantage compared with the corresponding income group in the settled majority population. Downward social mobility, differences in health-related lifestyles and the healthy migrant effect may explain this phenomenon.

Food security and environmental degradation in northern Nigeria: demographic perspectives.

PubMed

Lockwood, M

1991-07-01

The Malthusian controversy about the causes of environmental change and food insecurity in Hausaland in northern Nigeria is examined. The argument is irresolvable based on available data at the macro level. The individual and household level are appropriate for answering the question about how high density populations survive on a savannah. To understand population pressure in Hausaland, it is important to read Malthus very carefully and to understand the existing demographic structure in which economic and kinship relations support high fertility even where land is scarce. Demographic responses vary with economic strata. Policies ignore individual level differences. Since 1953, the densely populated areas of Sokoto, Katsina, Zaria, and Kano have spread in an area that is largely dry with a moderate-to-high risk of desertification. Food insecurity exists not only in times of drought, but also annually in the form of chronic shortages of staples for poor farmers. Average land holdings/capita have become smaller. Population pressure has also contributed to shifts in land use. Food prices have increased. Possible explanations include 1) the drought and the oil boom have a greater impact on environmental change and food insecurity and rural Hausa farmers have responded by raising yields, managing tree resources, and practicing soil conservation and 2) an independent source of income from non-agricultural activities is an essential part of the economy. The relationship among population pressure, land shortage, and food insecurity is complex. It is inaccurate to label Hausa as subsistence farmers, when trading in grain is an important enterprise. The role that commercialization of agriculture plays in food insecurity is discussed. Malthusian disaster is not imminent. The proximate determinants of fertility, birth spacing practices and infertility, should lead to high fertility rates, but in this case they do not. Determinants responsive to economic factors tend to be contraception and marriage, which are both marginal in the north. The Hausa system is demographically unresponsive, but it is economically and social absorptive of population pressure.

Crime and violence in Brazil: Systematic review of time trends, prevalence rates and risk factors☆

PubMed Central

Murray, Joseph; Cerqueira, Daniel Ricardo de Castro; Kahn, Tulio

2013-01-01

Between 1980 and 2010 there were 1 million homicides in Brazil. Dramatic increases in homicide rates followed rises in inequality, more young men in the population, greater availability of firearms, and increased drug use. Nevertheless, disarmament legislation may have helped reduce homicide rates in recent years. Despite its very high rate of lethal violence, Brazil appears to have similar levels of general criminal victimization as several other Latin American and North American countries. Brazil has lower rates of drug use compared to other countries such as the United States, but the prevalence of youth drug use in Brazil has increased substantially in recent years. Since 1990, the growth of the Brazilian prison population has been enormous, resulting in the fourth largest prison population in the world. Through a systematic review of the literature, we identified 10 studies assessing the prevalence of self-reported offending in Brazil and 9 studies examining risk factors. Levels of self-reported offending seem quite high among school students in Brazil. Individual and family-level risk factors identified in Brazil are very similar to those found in high-income countries. PMID:24027422

An Approach to Developing Local Climate Change Environmental Public Health Indicators in a Rural District.

PubMed

Houghton, Adele; Austin, Jessica; Beerman, Abby; Horton, Clayton

2017-01-01

Climate change represents a significant and growing threat to population health. Rural areas face unique challenges, such as high rates of vulnerable populations; economic uncertainty due to their reliance on industries that are vulnerable to climate change; less resilient infrastructure; and lower levels of access to community and emergency services than urban areas. This article fills a gap in public health practice by developing climate and health environmental public health indicators for a local public health department in a rural area. We adapted the National Environmental Public Health Tracking Network's framework for climate and health indicators to a seven-county health department in Western Kentucky. Using a three-step review process, we identified primary climate-related environmental public health hazards for the region (extreme heat, drought, and flooding) and a suite of related exposure, health outcome, population vulnerability, and environmental vulnerability indicators. Indicators that performed more poorly at the county level than at the state and national level were defined as "high vulnerability." Six to eight high vulnerability indicators were identified for each county. The local health department plans to use the results to enhance three key areas of existing services: epidemiology, public health preparedness, and community health assessment.

Population: fiction and fact.

PubMed

1979-09-01

This article was written to refute some common misunderstandings regarding worldwide population levels and worldwide nutrition levels. The world food supply is able to keep pace with high population growth levels. Worl food production currently meets world need; the problem is a distribution system which allocates food only to those who can pay rather than to those who need it. In many developing countries, the best agricultural lands are reserved for commercial crops rather than for subsistence crops. The U.S. food aid program does not help the most needy nations generally. The rate of world population growth is already slowing down. The desire for large families in developing countries is very often a realistic reaction to the prevailing economic system. Family planning programs will succeed. They will succeed even better in countries where general development planning is undertaken concurrently with family planning. Environmental problems are attributable to the consumption explosion in the rich countries rather than to the population explosion in the poor countries.

Intra-population level variation in thresholds for physical dormancy-breaking temperature

PubMed Central

Liyanage, Ganesha S.; Ooi, Mark K. J.

2015-01-01

Background and Aims Intra-population variation in seed dormancy is an advantage for population persistence in unpredictable environments. The important role played by physically dormant species in these habitats makes understanding the level of variation in their dormancy a key ecological question. Heat produced in the soil is the major dormancy-breaking stimulus and, in fire prone ecosystems, soil temperatures generated by fire may vary spatially and over time. While many studies have investigated variation in initial dormancy, a measure that is of little value in fire-prone ecosystems, where initial dormancy levels are uniformly high, intra-population variation in dormancy-breaking temperature thresholds has never been quantified. This study predicted that species would display variation in dormancy-breaking temperature thresholds within populations, and investigated whether this variation occurred between individual plants from the same maternal environment. Methods The intra-population variation in dormancy-breaking thresholds of five common physically dormant shrub species (family Fabaceae) from fire-prone vegetation in south-eastern Australia was assessed using heat treatments and germination trials. Replicate batches of seeds from each of four maternal plants of Dillwynia floribunda, Viminaria juncea, Bossiaea heterophylla, Aotus ericoides and Acacia linifolia were treated at 40, 60, 80, 100 and 120 °C. Key Results Dormancy-breaking response to heat treatments varied significantly among individual plants for all species, with some individuals able to germinate after heating at low temperatures and others restricting germination to temperatures that only occur as a result of high-severity fires. Germination rate (T50) varied among individuals of three species. Conclusions Variation detected among individuals that were in close proximity to each other indicates that strong differences in dormancy-breaking temperature thresholds occur throughout the broader population. Differences found at the individual plant level could contribute to subsequent variation within the seed bank, providing a bet-hedging strategy, and represent a mechanism for increasing the probability of population persistence in the face of fire regime variability. PMID:25997432

Road Traffic Noise

NASA Astrophysics Data System (ADS)

Beckenbauer, Thomas

Road traffic is the most interfering noise source in developed countries. According to a publication of the European Union (EU) at the end of the twentieth century [1], about 40% of the population in 15 EU member states is exposed to road traffic noise at mean levels exceeding 55 dB(A). Nearly 80 million people, 20% of the population, are exposed to levels exceeding 65 dB(A) during daytime and more than 30% of the population is exposed to levels exceeding 55 dB(A) during night time. Such high noise levels cause health risks and social disorders (aggressiveness, protest, and helplessness), interference of communication and disturbance of sleep; the long- and short-term consequences cause adverse cardiovascular effects, detrimental hormonal responses (stress hormones), and possible disturbance of the human metabolism (nutrition) and the immune system. Even performance at work and school could be impaired.

Plasma selenium levels and oxidative stress biomarkers: a gene-environment interaction population-based study.

PubMed

Galan-Chilet, Inmaculada; Tellez-Plaza, Maria; Guallar, Eliseo; De Marco, Griselda; Lopez-Izquierdo, Raul; Gonzalez-Manzano, Isabel; Carmen Tormos, M; Martin-Nuñez, Gracia M; Rojo-Martinez, Gemma; Saez, Guillermo T; Martín-Escudero, Juan C; Redon, Josep; Javier Chaves, F

2014-09-01

The role of selenium exposure in preventing chronic disease is controversial, especially in selenium-repleted populations. At high concentrations, selenium exposure may increase oxidative stress. Studies evaluating the interaction of genetic variation in genes involved in oxidative stress pathways and selenium are scarce. We evaluated the cross-sectional association of plasma selenium concentrations with oxidative stress levels, measured as oxidized to reduced glutathione ratio (GSSG/GSH), malondialdehyde (MDA), and 8-oxo-7,8-dihydroguanine (8-oxo-dG) in urine, and the interacting role of genetic variation in oxidative stress candidate genes, in a representative sample of 1445 men and women aged 18-85 years from Spain. The geometric mean of plasma selenium levels in the study sample was 84.76 µg/L. In fully adjusted models the geometric mean ratios for oxidative stress biomarker levels comparing the highest to the lowest quintiles of plasma selenium levels were 0.61 (0.50-0.76) for GSSG/GSH, 0.89 (0.79-1.00) for MDA, and 1.06 (0.96-1.18) for 8-oxo-dG. We observed nonlinear dose-responses of selenium exposure and oxidative stress biomarkers, with plasma selenium concentrations above ~110 μg/L being positively associated with 8-oxo-dG, but inversely associated with GSSG/GSH and MDA. In addition, we identified potential risk genotypes associated with increased levels of oxidative stress markers with high selenium levels. Our findings support that high selenium levels increase oxidative stress in some biological processes. More studies are needed to disentangle the complexity of selenium biology and the relevance of potential gene-selenium interactions in relation to health outcomes in human populations. Copyright © 2014 Elsevier Inc. All rights reserved.

Integrating mechanistic and polymorphism data to characterize human genetic susceptibility for environmental chemical risk assessment in the 21st century

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mortensen, Holly M., E-mail: mortensen.holly@epa.gov; Euling, Susan Y.

Response to environmental chemicals can vary widely among individuals and between population groups. In human health risk assessment, data on susceptibility can be utilized by deriving risk levels based on a study of a susceptible population and/or an uncertainty factor may be applied to account for the lack of information about susceptibility. Defining genetic susceptibility in response to environmental chemicals across human populations is an area of interest in the NAS' new paradigm of toxicity pathway-based risk assessment. Data from high-throughput/high content (HT/HC), including -omics (e.g., genomics, transcriptomics, proteomics, metabolomics) technologies, have been integral to the identification and characterization ofmore » drug target and disease loci, and have been successfully utilized to inform the mechanism of action for numerous environmental chemicals. Large-scale population genotyping studies may help to characterize levels of variability across human populations at identified target loci implicated in response to environmental chemicals. By combining mechanistic data for a given environmental chemical with next generation sequencing data that provides human population variation information, one can begin to characterize differential susceptibility due to genetic variability to environmental chemicals within and across genetically heterogeneous human populations. The integration of such data sources will be informative to human health risk assessment.« less

Evolutionarily stable disequilibrium: endless dynamics of evolution in a stationary population.

PubMed

Takeuchi, Nobuto; Kaneko, Kunihiko; Hogeweg, Paulien

2016-05-11

Evolution is often conceived as changes in the properties of a population over generations. Does this notion exhaust the possible dynamics of evolution? Life is hierarchically organized, and evolution can operate at multiple levels with conflicting tendencies. Using a minimal model of such conflicting multilevel evolution, we demonstrate the possibility of a novel mode of evolution that challenges the above notion: individuals ceaselessly modify their genetically inherited phenotype and fitness along their lines of descent, without involving apparent changes in the properties of the population. The model assumes a population of primitive cells (protocells, for short), each containing a population of replicating catalytic molecules. Protocells are selected towards maximizing the catalytic activity of internal molecules, whereas molecules tend to evolve towards minimizing it in order to maximize their relative fitness within a protocell. These conflicting evolutionary tendencies at different levels and genetic drift drive the lineages of protocells to oscillate endlessly between high and low intracellular catalytic activity, i.e. high and low fitness, along their lines of descent. This oscillation, however, occurs independently in different lineages, so that the population as a whole appears stationary. Therefore, ongoing evolution can be hidden behind an apparently stationary population owing to conflicting multilevel evolution. © 2016 The Authors.

Should there be a target level of docosahexaenoic acid in breast milk?

PubMed

Jackson, Kristina Harris; Harris, William S

2016-03-01

This article examines the evidence for and against establishing a target level of docosahexaenoic acid (DHA) in breast milk. Two target levels for milk DHA have been recently proposed. One (∼0.3% of milk fatty acids) was based on milk DHA levels achieved in women consuming the amount of DHA recommended by the American Academy of Pediatrics for pregnant and lactating women (at least 200 mg DHA/day). Another (∼1.0%) was based on biomarker studies of populations with differing lifelong intakes of fish. Populations or research cohorts with milk DHA levels of 1.0% are associated with intakes that allow both the mother and infant to maintain relatively high DHA levels throughout lactation. Lower milk DHA levels may signal suboptimal maternal stores and possibly suboptimal infant intakes. Based on the current data, a reasonable milk DHA target appears to be approximately 0.3%, which is about the worldwide average. Although this may not be the 'optimal' level (which remains to be defined), it is clearly an improvement over the currently low milk DHA levels (∼0.2%) seen in many Western populations.

Mitochondrial DNA diversity of orchid bee Euglossa fimbriata (Hymenoptera: Apidae) populations assessed by PCR-RFLP.

PubMed

Suzuki, Karen M; Arias, Maria C; Giangarelli, Douglas C; Freiria, Gabriele A; Sofia, Silvia H

2010-04-01

Euglossa fimbriata is a euglossine species widely distributed in Brazil and occurring primarily in Atlantic Forest remnants. In this study, the genetic mitochondrial structure of E. fimbriata from six Atlantic Forest fragments was studied by RFLP analysis of three PCR-amplified mtDNA gene segments (16S, COI-COII, and cyt b). Ten composite haplotypes were identified, six of which were exclusive and represented singleton mitotypes. Low haplotype diversity (0.085-0.289) and nucleotide diversity (0.000-0.002) were detected within samples. AMOVA partitioned 91.13% of the overall genetic variation within samples and 8.87% (phi(st) = 0.089; P < 0.05) among samples. Pairwise comparisons indicated high levels of differentiation among some pairs of samples (phi(st) = 0.161-0.218; P < 0.05). These high levels indicate that these populations of E. fimbriata, despite their highly fragmented landscape, apparently have not suffered loss of genetic variation, suggesting that this particular population is not currently endangered.

Predict value of adiponectin for coronary atherosclerosis plaques according to computed tomography angiography in an asymptomatic population.

PubMed

Gan, Lu; Yang, Li; Yan, Guangtao

2018-05-25

The association between serum adiponectin levels and coronary atherosclerosis plaque characteristics in asymptomatic populations is unclear. To examine the predictive value of serum adiponectin levels for coronary high risk plaques as detected by computed tomography angiography (CTA). This was a cross-sectional study. All patients were divided into high risk plaque group and non high risk plaque group. The FRS was calculated for each patient. CTA was performed for each patient. Adiponectin levels were measured by flow fluorescence immunmicrobead assay (FFIA). Receiver-operating characteristic (ROC) curves and multivariate analysis was used to determine the predictive value of adiponectin for high risk plaques. The high risk plaque group showed lower adiponectin levels than non high risk plaque group (median, 7.27 vs. 8.51 μg/ml, P = 0.003). The multivariate analysis showed that age (OR = 2.62, 95%CI: 1.51-4.56, P = 0.001), hyperlipidemia (OR = 1.89, 95%CI: 1.07-3.36, P = 0.029), high-density lipoprotein cholesterol (HDL-C) (OR = 0.46, 95%CI: 0.24-0.87, P = 0.02), the ratio of total cholesterol to high-density lipoproteincholesterol (TC/HDL-C) (OR = 0.69, 95%CI: 0.50-0.94, P = 0.02), apolipoprotein B (apoB) (OR = 3.08, 95%CI: 1.50-6.32, P = 0.002), and adiponectin (OR = 0.37, 95%CI: 0.19-0.74, P = 0.005) were independently associated with the presence of high risk plaques. AUC of the multivariate model for high-risk plaques was 0.728 (95%CI: 0.627-0.783). Sensitivity was 74.9%, specificity was 60.2%, the positive predictive value was 65.3%, and the negative predictive value was 70.6%. Decreased adiponectin levels were associated with the presence of high-risk plaques in asymptomatic populations at low to intermediate FRS. Adiponectin can play an important role in plaque screening before coronary CTA. Copyright © 2018 Elsevier Inc. All rights reserved.

Occurrence of alfalfa (Medicago sativa L.) populations along roadsides in southern Manitoba, Canada and their potential role in intraspecific gene flow.

PubMed

Bagavathiannan, Muthukumar V; Gulden, Robert H; Van Acker, Rene C

2011-04-01

Alfalfa is a highly outcrossing perennial species that can be noticed in roadsides as feral populations. There remains little information available on the extent of feral alfalfa populations in western Canadian prairies and their role in gene flow. The main objectives of this study were (a) to document the occurrence of feral alfalfa populations, and (b) to estimate the levels of outcrossing facilitated by feral populations. A roadside survey confirmed widespread occurrence of feral alfalfa populations, particularly in alfalfa growing regions. The feral populations were dynamic and their frequency ranged from 0.2 to 1.7 populations km(-1). In many cases, the nearest feral alfalfa population from alfalfa production field was located within a distance sufficient for outcrossing in alfalfa. The gene flow study confirmed that genes can move back and forth between feral and cultivated alfalfa populations. In this study, the estimated outcrossing levels were 62% (seed fields to feral), 78% (feral to seed fields), 82% (hay fields to feral) and 85% (feral to feral). Overall, the results show that feral alfalfa plants are prevalent in alfalfa producing regions in western Canada and they can serve as bridges for gene flow at landscape level. Management of feral populations should be considered, if gene flow is a concern. Emphasis on preventing seed spill/escapes and intentional roadside planting of alfalfa cultivars will be particularly helpful. Further, realistic and pragmatic threshold levels should be established for markets sensitive to the presence of GE traits.

The Relationship between Pay and Job Satisfaction: A Meta-Analysis of the Literature

ERIC Educational Resources Information Center

Judge, Timothy A.; Piccolo, Ronald F.; Podsakoff, Nathan P.; Shaw, John C.; Rich, Bruce L.

2010-01-01

Whereas the motivational aspects of pay are well-documented, the notion that high pay leads to high levels of satisfaction is not without debate. The current study used meta-analysis to estimate the population correlation between pay level and measures of pay and job satisfaction. Cumulating across 115 correlations from 92 independent samples,…

Habitat characterization of western hoolock gibbons Hoolock hoolock by examining home range microhabitat use.

PubMed

Akers, Alice A; Anwarul Islam, Md; Nijman, Vincent

2013-10-01

Conserving a species depends on an understanding of its habitat requirements. Primatologists often characterize the habitat requirements of primates using macroscale population-based approaches relying on correlations between habitat attributes and population abundances between sites with varying levels of disturbance. This approach only works for species spread between several populations. The populations of some primates do not fulfill these criteria, forcing researchers to rely on individual-based (microscale) rather than population-based approaches for habitat characterization. We examined the reliability of using micro-scale habitat characterizations by studying the microhabitat preferences of a group of wild western hoolock gibbons (Hoolock hoolock) in order to compare our results to the habitat preferences of western hoolock gibbons identified during a macroscale study of populations across Bangladesh. We used stepwise discriminant analysis to differentiate between the areas of low, medium, and high usage based on microhabitat characteristics (tree species availability, altitude, canopy connection, distance from forest edge, and levels of human disturbance). The gibbons used interior forest habitat with low food tree availability most frequently for sleeping and socializing, and used edge habitat containing high food tree availability for medium periods for feeding. These results indicate that the gibbons prefer interior forest but are frequently forced to visit the forest edge to feed. Therefore, the optimal habitat would be interior forest away from human disturbance with high sleeping-tree and feeding-tree availability. These habitat preferences are consistent with the habitat attributes of Bangladesh's largest remaining western hoolock gibbon populations, which live in areas containing low agricultural encroachment and high food-tree availability. Microhabitat use studies can be used to characterize the habitat requirements of a species, but should include multiple scales of analysis wherever possible.

An automated image processing routine for segmentation of cell cytoplasms in high-resolution autofluorescence images

NASA Astrophysics Data System (ADS)

Walsh, Alex J.; Skala, Melissa C.

2014-02-01

The heterogeneity of genotypes and phenotypes within cancers is correlated with disease progression and drug-resistant cellular sub-populations. Therefore, robust techniques capable of probing majority and minority cell populations are important both for cancer diagnostics and therapy monitoring. Herein, we present a modified CellProfiler routine to isolate cytoplasmic fluorescence signal on a single cell level from high resolution auto-fluorescence microscopic images.

Seasons of Change: Lessons from the Arab Spring

DTIC Science & Technology

2012-05-17

democratic feelings sweeping the populations in the region. Others have pointed to the high levels of corruption and unemployment in North Africa and the...unsustainable unemployment , high food prices, and local government corruption. The population also largely felt disenfranchised by the political process. The...in small businesses and the franchising of U.S. companies in Tunisia. Additionally, OPIC is providing U.S. companies with incentives to invest in

The Collaborative Cross at Oak Ridge National Laboratory: developing a powerful resource for systems genetics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chesler, Elissa J; Branstetter, Lisa R; Churchill, Gary A

2008-01-01

Complex traits and disease co-morbidity in humans and in model organisms are the result of naturally occurring polymorphisms that interact with each other and with the environment. To ensure the availability of the resources needed to investigate biomolecular networks and ultimately systems level phenotypes, we have initiated breeding of a new genetic reference population of mice, the Collaborative Cross. This population has been designed to optimally support systems genetics analysis. Its novel and important features include high levels of genetic diversity, a large population size to ensure sufficient power in high-dimensional studies, and high mapping precision through accumulation of independentmore » recombination events. Implementation of the Collaborative Cross has been in progress at the Oak Ridge National Laboratory (ORNL) since May 2005. This is achieved through a software assisted breeding program with fully traceable lineages, performed in a uniform environment. Currently, there are 650 lines in production with almost 200 lines over seven generations of inbreeding. Retired breeders enter a high-throughput phenotyping protocol and DNA samples are banked for analysis of recombination history, allele loss, and population structure. Herein we present a progress report of the Collaborative Cross breeding program at ORNL and a description of the kinds of investigations that this resource will support.« less

Comparative Phylogeography of Direct-Developing Frogs (Anura: Craugastoridae: Pristimantis) in the Southern Andes of Colombia

PubMed Central

García-R, Juan C.; Crawford, Andrew J.; Mendoza, Ángela María; Ospina, Oscar; Cardenas, Heiber; Castro, Fernando

2012-01-01

The Andes of South America hosts perhaps the highest amphibian species diversity in the world, and a sizable component of that diversity is comprised of direct-developing frogs of the genus Pristimantis (Anura: Craugastoridae). In order to better understand the initial stages of species formation in these frogs, this study quantified local-scale spatial genetic structuring in three species of Pristimantis. DNA sequences of two mitochondrial gene fragments (16S and COI) were obtained from P. brevifrons, P. palmeri and P. jubatus at different locations in the Cordillera Occidental. We found high levels of genetic diversity in the three species, with highly structured populations (as measured by F ST) in P. brevifrons and P. palmeri while P. jubatus showed panmixia. Large effective population sizes, inferred from the high levels of genetic diversity, were found in the three species and two highly divergent lineages were detected within P. jubatus and P. palmeri. Estimated divergence times among populations within P. brevifrons and P. palmeri coincide with the Pleistocene, perhaps due to similar responses to climatic cycling or recent geological history. Such insights have important implications for linking alpha and beta diversity, suggesting regional scale patterns may be associated with local scale processes in promoting differentiation among populations in the Andes. PMID:23049941

[Spanish adaptation of the 2016 European Guidelines on cardiovascular disease prevention in clinical practice].

PubMed

Royo-Bordonada, Miguel Ángel; Armario, Pedro; Lobos Bejarano, José María; Pedro-Botet, Juan; Villar Álvarez, Fernando; Elosua, Roberto; Brotons Cuixart, Carlos; Cortés, Olga; Serrano, Benilde; Camafort Babkowski, Miguel; Gil Núñez, Antonio; Pérez, Antonio; Maiques, Antonio; de Santiago Nocito, Ana; de Castro, Almudena; Alegría, Eduardo; Baeza, Ciro; Herranz, María; Sans, Susana; Campos, Pilar

The VI European Guidelines for Cardiovascular Prevention recommend combining population and high-risk strategies with lifestyle changes as a cornerstone of prevention, and propose the SCORE function to quantify cardiovascular risk. The guidelines highlight disease specific interventions, and conditions as women, young people and ethnic minorities. Screening for subclinical atherosclerosis with noninvasive imaging techniques is not recommended. The guidelines distinguish four risk levels (very high, high, moderate and low) with therapeutic objectives for lipid control according to risk. Diabetes mellitus confers a high risk, except for subjects with type 2 diabetes with less than <10 years of evolution, without other risk factors or complications, or type 1 diabetes of short evolution without complications. The decision to start pharmacological treatment of arterial hypertension will depend on the blood pressure level and the cardiovascular risk, taking into account the lesion of target organs. The guidelines don't recommend antiplatelet drugs in primary prevention because of the increased bleeding risk. The low adherence to the medication requires simplified therapeutic regimes and to identify and combat its causes. The guidelines highlight the responsibility of health professionals to take an active role in advocating evidence-based interventions at the population level, and propose effective interventions, at individual and population level, to promote a healthy diet, the practice of physical activity, the cessation of smoking and the protection against alcohol abuse. Copyright © 2017. Publicado por Elsevier España, S.L.U.

[Spanish adaptation of the 2016 European Guidelines on cardiovascular disease prevention in clinical practice].

PubMed

Royo-Bordonada, M Á; Armario, P; Lobos Bejarano, J M; Pedro-Botet, J; Villar Alvarez, F; Elosua, R; Brotons Cuixart, C; Cortés, O; Serrano, B; Cammafort Babkowski, M; Gil Núñez, A; Pérez, A; Maiques, A; de Santiago Nocito, A; Castro, A; Alegría, E; Baeza, C; Herranz, M; Sans, S; Campos, P

The VI European Guidelines for Cardiovascular Prevention recommend combining population and high-risk strategies with lifestyle changes as a cornerstone of prevention, and propose the SCORE function to quantify cardiovascular risk. The guidelines highlight disease specific interventions, and conditions as women, young people and ethnic minorities. Screening for subclinical atherosclerosis with noninvasive imaging techniques is not recommended. The guidelines distinguish four risk levels (very high, high, moderate and low) with therapeutic objectives for lipid control according to risk. Diabetes mellitus confers a high risk, except for subjects with type 2 diabetes with less than <10 years of evolution, without other risk factors or complications, or type 1 diabetes of short evolution without complications. The decision to start pharmacological treatment of arterial hypertension will depend on the blood pressure level and the cardiovascular risk, taking into account the lesion of target organs. The guidelines don't recommend antiplatelet drugs in primary prevention because of the increased bleeding risk. The low adherence to the medication requires simplified therapeutic regimes and to identify and combat its causes. The guidelines highlight the responsibility of health professionals to take an active role in advocating evidence-based interventions at the population level, and propose effective interventions, at individual and population level, to promote a healthy diet, the practice of physical activity, the cessation of smoking and the protection against alcohol abuse. Copyright © 2016. Publicado por Elsevier España, S.L.U.

Spanish adaptation of the 2016 European Guidelines on cardiovascular disease prevention in clinical practice.

PubMed

Royo-Bordonada, M Á; Armario, P; Lobos Bejarano, J M; Pedro-Botet, J; Villar Alvarez, F; Elosua, R; Brotons Cuixart, C; Cortés, O; Serrano, B; Camafort Babkowski, M; Gil Núñez, A; Pérez, A; Maiques, A; de Santiago Nocito, A; Castro, A; Alegría, E; Baeza, C; Herranz, M; Sans, S; Campos, P

The VI European Guidelines for Cardiovascular Prevention recommend combining population and high-risk strategies with lifestyle changes as a cornerstone of prevention, and propose the SCORE function to quantify cardiovascular risk. The guidelines highlight disease specific interventions, and conditions as women, young people and ethnic minorities. Screening for subclinical atherosclerosis with noninvasive imaging techniques is not recommended. The guidelines distinguish four risk levels (very high, high, moderate and low) with therapeutic objectives for lipid control according to risk. Diabetes mellitus confers a high risk, except for subjects with type 2 diabetes with less than <10 years of evolution, without other risk factors or complications, or type 1 diabetes of short evolution without complications. The decision to start pharmacological treatment of arterial hypertension will depend on the blood pressure level and the cardiovascular risk, taking into account the lesion of target organs. The guidelines don't recommend antiplatelet drugs in primary prevention because of the increased bleeding risk. The low adherence to the medication requires simplified therapeutic regimes and to identify and combat its causes. The guidelines highlight the responsibility of health professionals to take an active role in advocating evidence-based interventions at the population level, and propose effective interventions, at individual and population level, to promote a healthy diet, the practice of physical activity, the cessation of smoking and the protection against alcohol abuse. Copyright © 2017. Publicado por Elsevier España, S.L.U.

Antiretroviral treatment knowledge and stigma--implications for programs and HIV treatment interventions in rural Tanzanian populations.

PubMed

Agnarson, Abela Mpobela; Levira, Francis; Masanja, Honorati; Ekström, Anna Mia; Thorson, Anna

2013-01-01

To analyse antiretroviral treatment (ART) knowledge and HIV- and ART-related stigma among the adult population in a rural Tanzanian community. Population-based cross-sectional survey of 694 adults (15-49 years of age). Latent class analysis (LCA) categorized respondents' levels of ART knowledge and of ART-related stigma. Multinomial logistic regression assessed the association between the levels of ART knowledge and HIV- and ART-related stigma, while controlling for the effects of age, gender, education, marital status and occupation. More than one-third of men and women in the study reported that they had never heard of ART. Among those who had heard of ART, 24% were east informed about ART, 8% moderately informed, and 68% highly informed. Regarding ART-related stigma, 28% were least stigmatizing, 41% moderately stigmatizing, and 31% highly stigmatizing toward persons taking ART. Respondents that had at least primary education were more likely to have high levels of knowledge about ART (OR 3.09, 95% CI 1.61-5.94). Participants highly informed about ART held less HIV- and ART-related stigma towards ART patients (OR 0.26, 95% CI 0.09-0.74). The lack of ART knowledge is broad, and there is a strong association between ART knowledge and individual education level. These are relevant findings for both HIV prevention and HIV treatment program interventions that address ART-related stigma across the entire spectrum of the community.

A systems model for immune cell interactions unravels the mechanism of inflammation in human skin.

PubMed

Valeyev, Najl V; Hundhausen, Christian; Umezawa, Yoshinori; Kotov, Nikolay V; Williams, Gareth; Clop, Alex; Ainali, Crysanthi; Ouzounis, Christos; Tsoka, Sophia; Nestle, Frank O

2010-12-02

Inflammation is characterized by altered cytokine levels produced by cell populations in a highly interdependent manner. To elucidate the mechanism of an inflammatory reaction, we have developed a mathematical model for immune cell interactions via the specific, dose-dependent cytokine production rates of cell populations. The model describes the criteria required for normal and pathological immune system responses and suggests that alterations in the cytokine production rates can lead to various stable levels which manifest themselves in different disease phenotypes. The model predicts that pairs of interacting immune cell populations can maintain homeostatic and elevated extracellular cytokine concentration levels, enabling them to operate as an immune system switch. The concept described here is developed in the context of psoriasis, an immune-mediated disease, but it can also offer mechanistic insights into other inflammatory pathologies as it explains how interactions between immune cell populations can lead to disease phenotypes.

Characterization of the genetic diversity and population structure for the yellow cattle in Taiwan based on microsatellite markers.

PubMed

Tu, Po-An; Lin, Der-Yuh; Li, Guang-Fu; Huang, Jan-Chi; Wang, De-Chi; Wang, Pei-Hwa

2014-01-01

In recent years, the population size of Taiwan yellow cattle has drastically declined, even become endangered. A preservation project, Taiwan Yellow Cattle Genetic Preservation Project (TYCGPP), was carried out at the Livestock Research Institute (LRI) Hengchun branch (1988-present). An analysis of intra- and inter- population variability was performed to be the first step to preserve this precious genetic resource. In this work, a total number of 140 individuals selected from the five Taiwan yellow cattle populations were analyzed using 12 microsatellite markers (loci). These markers determined the level of genetic variation within and among populations as well as the phylogenetic structure. The total number of alleles detected (122, 10.28 per locus) and the expected heterozygosity (0.712) indicated that these five populations had a high level of genetic variability. Bayesian cluster analysis showed that the most likely number of groups was 2 (K = 2). Genetic differentiation among clusters was moderate (F ST = 0.095). The result of AMOVA showed that yellow cattle in Taiwan had maintained a high level of within-population genetic differentiation (91%), the remainder being accounted for by differentiation among subpopulations (4%), and by differentiation among regions (5%). The results of STRUCTURE and principal component analysis (PCA) revealed two divergent clusters. The individual unrooted phylogenetic tree showed that some Kinmen yellow cattle in the Hengchun facility (KMHC individuals) were overlapped with Taiwan yellow cattle (TW) and Taiwan yellow cattle Hengchun (HC) populations. Also, they were overlapped with Kinmen × Taiwan (KT) and Kinmen yellow cattle (KM) populations. It is possible that KMHC kept similar phenotypic characteristics and analogous genotypes between TW and KM. A significant inbreeding coefficient (F IS = 0.185; P < 0.01) was detected, suggesting a medium level of inbreeding for yellow cattle in Taiwan. The hypothesis that yellow cattle in Taiwan were derived from two different clusters was also supported by the phylogenetic tree constructed by the UPGMA, indicating that the yellow cattle in Taiwan and in Kinmen should be treated as two different management units. This result will be applied to maintain a good level of genetic variability and rusticity (stress-resistance) and to avoid further inbreeding for yellow cattle population in Taiwan.

Genetic structure and seed-mediated dispersal rates of an endangered shrub in a fragmented landscape: a case study for Juniperus communis in northwestern Europe

PubMed Central

2011-01-01

Background Population extinction risk in a fragmented landscape is related to the differential ability of the species to spread its genes across the landscape. The impact of landscape fragmentation on plant population dynamics will therefore vary across different spatial scales. We quantified successful seed-mediated dispersal of the dioecious shrub Juniperus communis in a fragmented landscape across northwestern Europe by using amplified fragment length polymorphism (AFLP) markers. Furthermore we investigated the genetic diversity and structure on two spatial scales: across northwestern Europe and across Flanders (northern Belgium). We also studied whether seed viability and populations size were correlated with genetic diversity. Results Unexpectedly, estimated seed-mediated dispersal rates were quite high and ranged between 3% and 14%. No population differentiation and no spatial genetic structure were detected on the local, Flemish scale. A significant low to moderate genetic differentiation between populations was detected at the regional, northwest European scale (PhiPT = 0.10). In general, geographically nearby populations were also genetically related. High levels of within-population genetic diversity were detected but no correlation was found between any genetic diversity parameter and population size or seed viability. Conclusions In northwestern Europe, landscape fragmentation has lead to a weak isolation-by-distance pattern but not to genetic impoverishment of common juniper. Substantial rates of successful migration by seed-mediated gene flow indicate a high dispersal ability which could enable Juniperus communis to naturally colonize suitable habitats. However, it is not clear whether the observed levels of migration will suffice to counterbalance the effects of genetic drift in small populations on the long run. PMID:21859457

Genetic structure and seed-mediated dispersal rates of an endangered shrub in a fragmented landscape: a case study for Juniperus communis in northwestern Europe.

PubMed

Vanden-Broeck, An; Gruwez, Robert; Cox, Karen; Adriaenssens, Sandy; Michalczyk, Inga M; Verheyen, Kris

2011-08-22

Population extinction risk in a fragmented landscape is related to the differential ability of the species to spread its genes across the landscape. The impact of landscape fragmentation on plant population dynamics will therefore vary across different spatial scales. We quantified successful seed-mediated dispersal of the dioecious shrub Juniperus communis in a fragmented landscape across northwestern Europe by using amplified fragment length polymorphism (AFLP) markers. Furthermore we investigated the genetic diversity and structure on two spatial scales: across northwestern Europe and across Flanders (northern Belgium). We also studied whether seed viability and populations size were correlated with genetic diversity. Unexpectedly, estimated seed-mediated dispersal rates were quite high and ranged between 3% and 14%. No population differentiation and no spatial genetic structure were detected on the local, Flemish scale. A significant low to moderate genetic differentiation between populations was detected at the regional, northwest European scale (PhiPT = 0.10). In general, geographically nearby populations were also genetically related. High levels of within-population genetic diversity were detected but no correlation was found between any genetic diversity parameter and population size or seed viability. In northwestern Europe, landscape fragmentation has lead to a weak isolation-by-distance pattern but not to genetic impoverishment of common juniper. Substantial rates of successful migration by seed-mediated gene flow indicate a high dispersal ability which could enable Juniperus communis to naturally colonize suitable habitats. However, it is not clear whether the observed levels of migration will suffice to counterbalance the effects of genetic drift in small populations on the long run.

High-level of resistance to spinosad, emamectin benzoate and carbosulfan in populations of Thrips tabaci collected in Israel.

PubMed

Lebedev, Galina; Abo-Moch, Fauzi; Gafni, Guy; Ben-Yakir, David; Ghanim, Murad

2013-02-01

The onion thrips, Thrips tabaci Lindeman, is a major pest of several crop plants in the genus Allium, such as onions, garlic and chives. In Israel, these crops are grown in open fields and in protected housing. This thrips is usually controlled by the application of chemical insecticides. In recent years, spinosad, emamectin benzoate and carbosulfan have been the major insecticides used for the control of the onion thrips. In the last 4 years, growers of chives and green onion from several regions of Israel have reported a significant decrease in the efficacy of insecticides used to control the onion thrips. The susceptibility of 14 populations of the onion thrips, collected mainly from chives between the years 2007 and 2011, to spinosad, emamectin benzoate and carbosulfan was tested using a laboratory bioassay. The majority of the populations showed significant levels of resistance to at least one of the insecticides. LC(50) values calculated for two of the studied populations showed that the resistance factor for spinosad compared with the susceptible population is 21 393, for carbosulfan 54 and for emamectin benzoate 36. Only two populations, collected from organic farms, were susceptible to the insecticides tested. This is the first report of a high resistance level to spinosad, the major insecticide used to control the onion thrips. Resistance cases to spinosad were associated with failures to control the pest. Populations resistant to spinosad also had partial or complete resistance to other insecticides used for controlling the onion thrips. Copyright © 2012 Society of Chemical Industry.

Microsatellite Genotyping of Plasmodium vivax Isolates from Pregnant Women in Four Malaria Endemic Countries

PubMed Central

Menegon, Michela; Bardají, Azucena; Martínez-Espinosa, Flor; Bôtto-Menezes, Camila; Ome-Kaius, Maria; Mueller, Ivo; Betuela, Inoni; Arévalo-Herrera, Myriam; Kochar, Swati; Kochar, Sanjay K.; Jaju, Puneet; Hans, Dhiraj; Chitnis, Chetan; Padilla, Norma; Castellanos, María Eugenia; Ortiz, Lucía; Sanz, Sergi; Piqueras, Mireia; Desai, Meghna; Mayor, Alfredo; del Portillo, Hernando; Menéndez, Clara; Severini, Carlo

2016-01-01

Plasmodium vivax is the most widely distributed human parasite and the main cause of human malaria outside the African continent. However, the knowledge about the genetic variability of P. vivax is limited when compared to the information available for P. falciparum. We present the results of a study aimed at characterizing the genetic structure of P. vivax populations obtained from pregnant women from different malaria endemic settings. Between June 2008 and October 2011 nearly 2000 pregnant women were recruited during routine antenatal care at each site and followed up until delivery. A capillary blood sample from the study participants was collected for genotyping at different time points. Seven P. vivax microsatellite markers were used for genotypic characterization on a total of 229 P. vivax isolates obtained from Brazil, Colombia, India and Papua New Guinea. In each population, the number of alleles per locus, the expected heterozygosity and the levels of multilocus linkage disequilibrium were assessed. The extent of genetic differentiation among populations was also estimated. Six microsatellite loci on 137 P. falciparum isolates from three countries were screened for comparison. The mean value of expected heterozygosity per country ranged from 0.839 to 0.874 for P. vivax and from 0.578 to 0.758 for P. falciparum. P. vivax populations were more diverse than those of P. falciparum. In some of the studied countries, the diversity of P. vivax population was very high compared to the respective level of endemicity. The level of inter-population differentiation was moderate to high in all P. vivax and P. falciparum populations studied. PMID:27011010

Genetic structure and diversity of the selfing model grass Brachypodium stacei (Poaceae) in Western Mediterranean: out of the Iberian Peninsula and into the islands.

PubMed

Shiposha, Valeriia; Catalán, Pilar; Olonova, Marina; Marques, Isabel

2016-01-01

Annual Mediterranean species of the genus Brachypodium are promising model plants for energy crops since their selfing nature and short-life cycles are an advantage in breeding programs. The false brome, B. distachyon, has already been sequenced and new genomic initiatives have triggered the de-novo genome sequencing of its close relatives such as B. stacei, a species that was until recently mistaken for B. distachyon. However, the success of these initiatives hinges on detailed knowledge about the distribution of genetic variation within and among populations for the effective use of germplasm in a breeding program. Understanding population genetic diversity and genetic structure is also an important prerequisite for designing effective experimental populations for genomic wide studies. However, population genetic data are still limited in B. stacei. We therefore selected and amplified 10 nuclear microsatellite markers to depict patterns of population structure and genetic variation among 181 individuals from 19 populations of B. stacei occurring in its predominant range, the western Mediterranean area: mainland Iberian Peninsula, continental Balearic Islands and oceanic Canary Islands. Our genetic results support the occurrence of a predominant selfing system with extremely high levels of homozygosity across the analyzed populations. Despite the low level of genetic variation found, two different genetic clusters were retrieved, one clustering all SE Iberian mainland populations and the island of Minorca and another one grouping all S Iberian mainland populations, the Canary Islands and all Majorcan populations except one that clustered with the former group. These results, together with a high sharing of alleles (89%) suggest different colonization routes from the mainland Iberian Peninsula into the islands. A recent colonization scenario could explain the relatively low levels of genetic diversity and low number of alleles found in the Canary Islands populations while older colonization events are hypothesized to explain the high genetic diversity values found in the Majorcan populations. Our study provides widely applicable information about geographical patterns of genetic variation in B. stacei. Among others, the genetic pattern and the existence of local alleles will need to be adequately reflected in the germplasm collection of B. stacei for efficient genome wide association studies.

Genetic structure and diversity of the selfing model grass Brachypodium stacei (Poaceae) in Western Mediterranean: out of the Iberian Peninsula and into the islands

PubMed Central

Shiposha, Valeriia; Catalán, Pilar; Olonova, Marina

2016-01-01

Annual Mediterranean species of the genus Brachypodium are promising model plants for energy crops since their selfing nature and short-life cycles are an advantage in breeding programs. The false brome, B. distachyon, has already been sequenced and new genomic initiatives have triggered the de-novo genome sequencing of its close relatives such as B. stacei, a species that was until recently mistaken for B. distachyon. However, the success of these initiatives hinges on detailed knowledge about the distribution of genetic variation within and among populations for the effective use of germplasm in a breeding program. Understanding population genetic diversity and genetic structure is also an important prerequisite for designing effective experimental populations for genomic wide studies. However, population genetic data are still limited in B. stacei. We therefore selected and amplified 10 nuclear microsatellite markers to depict patterns of population structure and genetic variation among 181 individuals from 19 populations of B. stacei occurring in its predominant range, the western Mediterranean area: mainland Iberian Peninsula, continental Balearic Islands and oceanic Canary Islands. Our genetic results support the occurrence of a predominant selfing system with extremely high levels of homozygosity across the analyzed populations. Despite the low level of genetic variation found, two different genetic clusters were retrieved, one clustering all SE Iberian mainland populations and the island of Minorca and another one grouping all S Iberian mainland populations, the Canary Islands and all Majorcan populations except one that clustered with the former group. These results, together with a high sharing of alleles (89%) suggest different colonization routes from the mainland Iberian Peninsula into the islands. A recent colonization scenario could explain the relatively low levels of genetic diversity and low number of alleles found in the Canary Islands populations while older colonization events are hypothesized to explain the high genetic diversity values found in the Majorcan populations. Our study provides widely applicable information about geographical patterns of genetic variation in B. stacei. Among others, the genetic pattern and the existence of local alleles will need to be adequately reflected in the germplasm collection of B. stacei for efficient genome wide association studies. PMID:27651993

A Novel Review of the Evidence Linking Myopia and High Intelligence

PubMed Central

Verma, Ajai; Verma, Abhishek

2015-01-01

The association between myopia and high intelligence has been the subject of much vexed debate in academic circles, particularly over the last two decades. This debate has risen from the observation that, over recent centuries, the prevalence of myopia amongst most populations has coincided with a marked increase in the average level of intelligence in these populations. The relationship between myopia and intelligence and theories surrounding this association is examined by the authors. Additionally, the various factors that confound the myopia and high intelligence debate, such as genetics, educational levels, ethnicity, and environmental factors were also explored by the authors. Whilst most studies found a positive correlation reaching statistical significance between myopia and high intelligence compared to emmetropes and hyperopes, further research is required to determine whether this association is causal. PMID:25653868

The effects of country-level population policy for enhancing adaptation to climate change

NASA Astrophysics Data System (ADS)

Gunasekara, N. K.; Kazama, S.; Yamazaki, D.; Oki, T.

2012-08-01

The effectiveness of population policy scenarios in reducing the combined impacts of population change and climate change on water resources is explored. One no-policy scenario and two scenarios with population policy assumptions are employed in combination with water availability under the SRES scenarios A1b, B1 and A2 for the impact analysis. The population data used are from the World Bank. The river discharges per grid of horizontal resolution 0.5° are obtained from the Total Runoff Integrating Pathways (TRIP) of the University of Tokyo, Japan. Unlike the population scenarios utilized in the SRES emission scenarios and the newest Representative Concentration Pathways, the scenarios employed in this research are based, even after 2050, on country-level rather than regional growth assumptions. Our analysis implies that in combination with a more heterogeneous pattern of population changes across the world, a more convergent, environmentally friendly emissions scenario, such as B1, can result in a high-impact climate scenario, similar to A2, for the already water-stressed low latitudes. However, the effect of population change supersedes the changes in the climate scenarios. In 2100, Africa, Middle-East and parts of Asia are in extreme water-stress under all scenarios. For countries with high population momentum, the population policy scenario with fertility-reduction assumptions gained a maximum of 6.1 times the water availability in Niger and 5.3 times that in Uganda compared with the no-policy scenario. Most of these countries are in Sub-Saharan Africa. These countries represent 24.5% of the global population in the no-policy scenario and the scenario with fertility- reduction assumptions reduces it to 8.7% by 2100. This scenario is also effective at reducing the area under extreme water stress in these countries. However, the policy scenario with assumptions of population stabilization at the replacement fertility rate increases the water stress in high-latitude countries. Nevertheless, the impact is low due to the high per capita water availability in the region. This research is expected to widen the understanding of the combined impacts of climate change in the future and of the strategies needed to enhance the space for adaptation.

Could Seals Prevent Cod Recovery in the Baltic Sea?

PubMed Central

MacKenzie, Brian R.; Eero, Margit; Ojaveer, Henn

2011-01-01

Fish populations are increasingly affected by multiple human and natural impacts including exploitation, eutrophication, habitat alteration and climate change. As a result many collapsed populations may have to recover in ecosystems whose structure and functioning differ from those in which they were formerly productive and supported sustainable fisheries. Here we investigate how a cod (Gadus morhua) population in the Baltic Sea whose biomass was reduced due to a combination of high exploitation and deteriorating environmental conditions might recover and develop in the 21st century in an ecosystem that likely will change due to both the already started recovery of a cod predator, the grey seal Halichoerus grypus, and projected climate impacts. Simulation modelling, assuming increased seal predation, fishing levels consistent with management plan targets and stable salinity, shows that the cod population could reach high levels well above the long-term average. Scenarios with similar seal and fishing levels but with 15% lower salinity suggest that the Baltic will still be able to support a cod population which can sustain a fishery, but biomass and yields will be lower. At present knowledge of cod and seal interactions, seal predation was found to have much lower impact on cod recovery, compared to the effects of exploitation and salinity. These results suggest that dual management objectives (recovery of both seal and cod populations) are realistic but success in achieving these goals will also depend on how climate change affects cod recruitment. PMID:21573062

Modern Prescription Theory and Application: Realistic Expectations for Speech Recognition With Hearing Aids

PubMed Central

2013-01-01

A major decision at the time of hearing aid fitting and dispensing is the amount of amplification to provide listeners (both adult and pediatric populations) for the appropriate compensation of sensorineural hearing impairment across a range of frequencies (e.g., 160–10000 Hz) and input levels (e.g., 50–75 dB sound pressure level). This article describes modern prescription theory for hearing aids within the context of a risk versus return trade-off and efficient frontier analyses. The expected return of amplification recommendations (i.e., generic prescriptions such as National Acoustic Laboratories—Non-Linear 2, NAL-NL2, and Desired Sensation Level Multiple Input/Output, DSL m[i/o]) for the Speech Intelligibility Index (SII) and high-frequency audibility were traded against a potential risk (i.e., loudness). The modeled performance of each prescription was compared one with another and with the efficient frontier of normal hearing sensitivity (i.e., a reference point for the most return with the least risk). For the pediatric population, NAL-NL2 was more efficient for SII, while DSL m[i/o] was more efficient for high-frequency audibility. For the adult population, NAL-NL2 was more efficient for SII, while the two prescriptions were similar with regard to high-frequency audibility. In terms of absolute return (i.e., not considering the risk of loudness), however, DSL m[i/o] prescribed more outright high-frequency audibility than NAL-NL2 for either aged population, particularly, as hearing loss increased. Given the principles and demonstrated accuracy of desensitization (reduced utility of audibility with increasing hearing loss) observed at the group level, additional high-frequency audibility beyond that of NAL-NL2 is not expected to make further contributions to speech intelligibility (recognition) for the average listener. PMID:24253361

The double burden of malnutrition in indigenous and nonindigenous Guatemalan populations.

PubMed

Ramirez-Zea, Manuel; Kroker-Lobos, Maria F; Close-Fernandez, Regina; Kanter, Rebecca

2014-12-01

As the prevalence of obesity increases in developing countries, the double burden of malnutrition (DBM) has become a public health problem, particularly in countries such as Guatemala with a high concentration of indigenous communities where the prevalence of stunting remains high. The aim was to describe and analyze the prevalence of DBM over time (1998-2008) in indigenous and nonindigenous Guatemalan populations. We used 3 National Maternal and Child Health Surveys conducted in Guatemala between 1998 and 2008 that include anthropometric data from children aged 0-60 mo and women of reproductive age (15-49 y). We assessed the prevalence of childhood stunting and both child and adult female overweight and obesity between 1998 and 2008. For the year 2008, we assessed the prevalence of DBM at the household (a stunted child and an overweight mother) and individual (stunting/short stature and overweight or anemia and overweight in the same individual) levels and compared the expected and observed prevalence rates to test if the coexistence of the DBM conditions corresponded to expected values. Between 1998 and 2008, the prevalence of childhood stunting decreased in both indigenous and nonindigenous populations, whereas overweight and obesity in women increased faster in indigenous populations than in nonindigenous populations (0.91% compared with 0.38%/y; P-trend < 0.01). In 2008, the prevalence of stunted children was 28.8 percentage points higher and of overweight women 4.6 percentage points lower in indigenous compared with nonindigenous populations (63.7% compared with 34.9% and 46.7% compared with 51.3%, respectively). DBM at the household and individual levels was higher in indigenous populations and was higher in geographic areas in which most of the population was indigenous, where there was also a greater prevalence of stunting and DBM at the individual level, both in women and children. In Guatemala, DBM is more prevalent in indigenous than in nonindigenous populations at the household and individual levels. To enhance effectiveness, current strategies of national policies and programs should consider DBM and focus on indigenous populations. © 2014 American Society for Nutrition.

Analysis on the Bullying Tendencies and Value Preferences of High School Students According to Level of Receiving Physical Education and Sports Course

ERIC Educational Resources Information Center

Savucu, Yüksel; Kanat, Metin; Karadag, Mustafa; Sezer, Süreyya. Y.; Yücel, Ali S.

2017-01-01

The aim of this study was to investigate the bullying tendencies and value preferences of high school students according to the level of taking physical education and sports course. The research population of the study was composed of high school students studying in Yesilyurt and Battalgazi districts of Malatya province during 2013-2014 academic…

Genomic patterns of introgression in rainbow and westslope cutthroat trout illuminated by overlapping paired-end RAD sequencing

USGS Publications Warehouse

Hohenlohe, Paul A.; Day, Mitch D.; Amish, Stephen J.; Miller, Michael R.; Kamps-Hughes, Nick; Boyer, Matthew C.; Muhlfeld, Clint C.; Allendorf, Fred W.; Johnson, Eric A.; Luikart, Gordon

2013-01-01

Rapid and inexpensive methods for genomewide single nucleotide polymorphism (SNP) discovery and genotyping are urgently needed for population management and conservation. In hybridized populations, genomic techniques that can identify and genotype thousands of species-diagnostic markers would allow precise estimates of population- and individual-level admixture as well as identification of 'super invasive' alleles, which show elevated rates of introgression above the genomewide background (likely due to natural selection). Techniques like restriction-site-associated DNA (RAD) sequencing can discover and genotype large numbers of SNPs, but they have been limited by the length of continuous sequence data they produce with Illumina short-read sequencing. We present a novel approach, overlapping paired-end RAD sequencing, to generate RAD contigs of >300–400 bp. These contigs provide sufficient flanking sequence for design of high-throughput SNP genotyping arrays and strict filtering to identify duplicate paralogous loci. We applied this approach in five populations of native westslope cutthroat trout that previously showed varying (low) levels of admixture from introduced rainbow trout (RBT). We produced 77 141 RAD contigs and used these data to filter and genotype 3180 previously identified species-diagnostic SNP loci. Our population-level and individual-level estimates of admixture were generally consistent with previous microsatellite-based estimates from the same individuals. However, we observed slightly lower admixture estimates from genomewide markers, which might result from natural selection against certain genome regions, different genomic locations for microsatellites vs. RAD-derived SNPs and/or sampling error from the small number of microsatellite loci (n = 7). We also identified candidate adaptive super invasive alleles from RBT that had excessively high admixture proportions in hybridized cutthroat trout populations.

Lithium levels in tap water and psychotic experiences in a general population of adolescents.

PubMed

Shimodera, Shinji; Koike, Shinsuke; Ando, Shuntaro; Yamasaki, Syudo; Fujito, Ryosuke; Endo, Kaori; Iijima, Yudai; Yamamoto, Yu; Morita, Masaya; Sawada, Ken; Ohara, Nobuki; Okazaki, Yuji; Nishida, Atsushi

2018-06-09

Recently, several epidemiologic studies have reported that lithium in drinking water may be associated with lower rates of suicide mortality, lower incidence of dementia, and lower levels of adolescents' depression and aggression at the population level. However, to our knowledge, no study has investigated lithium level in tap water in relation to psychotic experiences in a general population of adolescents. This is the first study to investigate this using a large dataset. Information on psychotic experiences, distress associated with these experiences, and depressive symptoms were collected in 24 public junior high schools in Kochi Prefecture in Japan. Samples were collected from sources that supplied drinking water to schools, and lithium levels were measured using atomic absorption spectrophotometry. The association of lithium levels with psychotic experiences, considering distress as a degree of severity, was examined using an ordinal logistic regression model with schools and depressive symptoms as random effects. In total, 3040 students responded to the self-reporting questionnaire (response rate: 91.8%). Lithium levels in tap water were inversely associated with psychotic experiences (p = 0.021). We concluded that lithium level in tap water was inversely associated with psychotic experiences among a general population of adolescents and may have a preventive effect for such experiences and distress. Copyright © 2018 Elsevier B.V. All rights reserved.

Comparative Population Genomics Analysis of the Mammalian Fungal Pathogen Pneumocystis

PubMed Central

Ma, Liang; Wei Huang, Da; Khil, Pavel P.; Dekker, John P.; Kutty, Geetha; Bishop, Lisa; Liu, Yueqin; Deng, Xilong; Pagni, Marco; Hirsch, Vanessa; Lempicki, Richard A.

2018-01-01

ABSTRACT Pneumocystis species are opportunistic mammalian pathogens that cause severe pneumonia in immunocompromised individuals. These fungi are highly host specific and uncultivable in vitro. Human Pneumocystis infections present major challenges because of a limited therapeutic arsenal and the rise of drug resistance. To investigate the diversity and demographic history of natural populations of Pneumocystis infecting humans, rats, and mice, we performed whole-genome and large-scale multilocus sequencing of infected tissues collected in various geographic locations. Here, we detected reduced levels of recombination and variations in historical demography, which shape the global population structures. We report estimates of evolutionary rates, levels of genetic diversity, and population sizes. Molecular clock estimates indicate that Pneumocystis species diverged before their hosts, while the asynchronous timing of population declines suggests host shifts. Our results have uncovered complex patterns of genetic variation influenced by multiple factors that shaped the adaptation of Pneumocystis populations during their spread across mammals. PMID:29739910

Isolation with Migration Models for More Than Two Populations

PubMed Central

Hey, Jody

2010-01-01

A method for studying the divergence of multiple closely related populations is described and assessed. The approach of Hey and Nielsen (2007, Integration within the Felsenstein equation for improved Markov chain Monte Carlo methods in population genetics. Proc Natl Acad Sci USA. 104:2785–2790) for fitting an isolation-with-migration model was extended to the case of multiple populations with a known phylogeny. Analysis of simulated data sets reveals the kinds of history that are accessible with a multipopulation analysis. Necessarily, processes associated with older time periods in a phylogeny are more difficult to estimate; and histories with high levels of gene flow are particularly difficult with more than two populations. However, for histories with modest levels of gene flow, or for very large data sets, it is possible to study large complex divergence problems that involve multiple closely related populations or species. PMID:19955477

Isolation with migration models for more than two populations.

PubMed

Hey, Jody

2010-04-01

A method for studying the divergence of multiple closely related populations is described and assessed. The approach of Hey and Nielsen (2007, Integration within the Felsenstein equation for improved Markov chain Monte Carlo methods in population genetics. Proc Natl Acad Sci USA. 104:2785-2790) for fitting an isolation-with-migration model was extended to the case of multiple populations with a known phylogeny. Analysis of simulated data sets reveals the kinds of history that are accessible with a multipopulation analysis. Necessarily, processes associated with older time periods in a phylogeny are more difficult to estimate; and histories with high levels of gene flow are particularly difficult with more than two populations. However, for histories with modest levels of gene flow, or for very large data sets, it is possible to study large complex divergence problems that involve multiple closely related populations or species.

Genetic Diversity and Population Structure of Theileria annulata in Oman

PubMed Central

Al-Hamidhi, Salama; H. Tageldin, Mohammed.; Weir, William; Al-Fahdi, Amira; Johnson, Eugene H.; Bobade, Patrick; Alqamashoui, Badar; Beja-Pereira, Albano; Thompson, Joanne; Kinnaird, Jane; Shiels, Brian; Tait, Andy; Babiker, Hamza

2015-01-01

Background Theileriosis, caused by a number of species within the genus Theileria, is a common disease of livestock in Oman. It is a major constraint to the development of the livestock industry due to a high rate of morbidity and mortality in both cattle and sheep. Since little is currently known about the genetic diversity of the parasites causing theileriosis in Oman, the present study was designed to address this issue with specific regard to T. annulata in cattle. Methods Blood samples were collected from cattle from four geographically distinct regions in Oman for genetic analysis of the Theileria annulata population. Ten genetic markers (micro- and mini-satellites) representing all four chromosomes of T. annulata were applied to these samples using a combination of PCR amplification and fragment analysis. The resultant genetic data was analysed to provide a first insight into the structure of the T. annulata population in Oman. Results We applied ten micro- and mini-satellite markers to a total of 310 samples obtained from different regions (174 [56%] from Dhofar, 68 [22%] from Dhira, 44 [14.5%] from Batinah and 24 [8%] from Sharqia). A high degree of allelic diversity was observed among the four parasite populations. Expected heterozygosity for each site ranged from 0.816 to 0.854. A high multiplicity of infection was observed in individual hosts, with an average of 3.3 to 3.4 alleles per locus, in samples derived from Batinah, Dhofar and Sharqia regions. In samples from Dhira region, an average of 2.9 alleles per locus was observed. Mild but statistically significant linkage disequilibrium between pairs of markers was observed in populations from three of the four regions. In contrast, when the analysis was performed at farm level, no significant linkage disequilibrium was observed. Finally, no significant genetic differentiation was seen between the four populations, with most pair-wise FST values being less than 0.03. Slightly higher FST values (GST’ = 0.075, θ = 0.07) were detected when the data for T. annulata parasites in Oman was compared with that previously generated for Turkey and Tunisia. Conclusion Genetic analyses of T. annulata samples representing four geographical regions in Oman revealed a high level of genetic diversity in the parasite population. There was little evidence of genetic differentiation between parasites from different regions, and a high level of genetic diversity was maintained within each sub-population. These findings are consistent with a high parasite transmission rate and frequent movement of animals between different regions in Oman. PMID:26469349

Genetic Diversity and Population Structure of Theileria annulata in Oman.

PubMed

Al-Hamidhi, Salama; H Tageldin, Mohammed; Weir, William; Al-Fahdi, Amira; Johnson, Eugene H; Bobade, Patrick; Alqamashoui, Badar; Beja-Pereira, Albano; Thompson, Joanne; Kinnaird, Jane; Shiels, Brian; Tait, Andy; Babiker, Hamza

2015-01-01

Theileriosis, caused by a number of species within the genus Theileria, is a common disease of livestock in Oman. It is a major constraint to the development of the livestock industry due to a high rate of morbidity and mortality in both cattle and sheep. Since little is currently known about the genetic diversity of the parasites causing theileriosis in Oman, the present study was designed to address this issue with specific regard to T. annulata in cattle. Blood samples were collected from cattle from four geographically distinct regions in Oman for genetic analysis of the Theileria annulata population. Ten genetic markers (micro- and mini-satellites) representing all four chromosomes of T. annulata were applied to these samples using a combination of PCR amplification and fragment analysis. The resultant genetic data was analysed to provide a first insight into the structure of the T. annulata population in Oman. We applied ten micro- and mini-satellite markers to a total of 310 samples obtained from different regions (174 [56%] from Dhofar, 68 [22%] from Dhira, 44 [14.5%] from Batinah and 24 [8%] from Sharqia). A high degree of allelic diversity was observed among the four parasite populations. Expected heterozygosity for each site ranged from 0.816 to 0.854. A high multiplicity of infection was observed in individual hosts, with an average of 3.3 to 3.4 alleles per locus, in samples derived from Batinah, Dhofar and Sharqia regions. In samples from Dhira region, an average of 2.9 alleles per locus was observed. Mild but statistically significant linkage disequilibrium between pairs of markers was observed in populations from three of the four regions. In contrast, when the analysis was performed at farm level, no significant linkage disequilibrium was observed. Finally, no significant genetic differentiation was seen between the four populations, with most pair-wise FST values being less than 0.03. Slightly higher FST values (GST' = 0.075, θ = 0.07) were detected when the data for T. annulata parasites in Oman was compared with that previously generated for Turkey and Tunisia. Genetic analyses of T. annulata samples representing four geographical regions in Oman revealed a high level of genetic diversity in the parasite population. There was little evidence of genetic differentiation between parasites from different regions, and a high level of genetic diversity was maintained within each sub-population. These findings are consistent with a high parasite transmission rate and frequent movement of animals between different regions in Oman.

Genetic variants associated with fetal hemoglobin levels show the diverse ethnic origin in Colombian patients with sickle cell anemia.

PubMed

Fong, Cristian; Menzel, Stephan; Lizarralde, María Alejandra; Barreto, Guillermo

2015-01-01

Fetal hemoglobin is an important factor in modulating the severity of sickle cell anemia. Its level in peripheral blood underlies strong genetic determination. Associated loci with increased levels of fetal hemoglobin display population-specific allele frequencies. We investigated the presence and effect of known common genetic variants promoting fetal hemoglobin persistence (rs11886868, rs9399137, rs4895441, and rs7482144) in 60 Colombian patients with sickle cell anemia. Four single nucleotide polymorphisms (SNP) were genotyped by restriction fragment length polymorphisms (RFLP) and the use of the TaqMan procedure. Fetal hemoglobin (HbF) from these patients was quantified using the oxyhemoglobin alkaline denaturation technique. Genotype frequencies were compared with frequencies reported in global reference populations. We detected genetic variants in the four SNPs, reported to be associated with higher HbF levels for all four SNPs in the Colombian patients. Genetic association between SNPs and HbF levels did not reach statistical significance. The frequency of these variants reflected the specific ethnic make-up of our patient population: A high prevalence of rs7482144-'A' reflects the West-African origin of the sickle cell mutation, while high frequencies of rs4895441-'G' and rs11886868-'C' point to a significant influence of an Amerindian ethnic background in the Colombian sickle cell disease population. These results showed that in the sickle cell disease population in Colombia there is not a unique genetic background, but two (African and Amerindian). This unique genetic situation will provide opportunities for a further study of these loci, such as fine-mapping and molecular-biological investigation. Colombian patients are expected to yield a distinctive insight into the effect of modifier loci in sickle cell disease.

PM2.5, Population Exposure and Economic Effects in Urban Agglomerations of China Using Ground-Based Monitoring Data

PubMed Central

Shen, Yonglin

2017-01-01

This paper adopts the PM2.5 concentration data obtained from 1497 station-based monitoring sites, population and gross domestic product (GDP) census data, revealing population exposure and economic effects of PM2.5 in four typical urban agglomerations of China, i.e., Beijing-Tianjin-Hebei (BTH), the Yangtze River delta (YRD), the Pearl River delta (PRD), and Chengdu-Chongqing (CC). The Cokriging interpolation method was used to estimate the PM2.5 concentration from station-level to grid-level. Next, an evaluation was conducted mainly at the grid-level with a cell size of 1 × 1 km, assisted by the urban agglomeration scale. Criteria including the population-weighted mean, the cumulative percent distribution and the correlation coefficient were applied in our evaluation. The results showed that the spatial pattern of population exposure in BTH was consistent with that of PM2.5 concentration, as well as changes in elevation. The topography was also an important factor in the accumulation of PM2.5 in CC. Moreover, the most polluted urban agglomeration based on the population-weighted mean was BTH, while the least was PRD. In terms of the cumulative percent distribution, only 0.51% of the population who lived in the four urban agglomerations, and 2.33% of the GDP that was produced in the four urban agglomerations, were associated with an annual PM2.5 concentration smaller than the Chinese National Ambient Air Quality Standard of 35 µg/m3. This indicates that the majority of people live in the high air polluted areas, and economic development contributes to air pollution. Our results are supported by the high correlation between population exposure and the corresponding GDP in each urban agglomeration. PMID:28671643

Variation in P450-mediated fenvalerate resistance levels is not correlated with CYP337B3 genotype in Chinese populations of Helicoverpa armigera.

PubMed

Han, Yangchun; Yu, Wanting; Zhang, Weiqing; Yang, Yihua; Walsh, Tom; Oakeshott, John G; Wu, Yidong

2015-06-01

Metabolic resistance to synthetic pyrethroids in Helicoverpa   armigera has recently been associated with the chimeric cytochrome P450 enyzme CYP337B3. One variant of the latter, CYP337B3v1, accounts for 40-50 fold resistance to fenvalerate in an Australian population while a second variant, CYP337B3v2, has been associated with ~7 fold resistance to cypermethrin in a Pakistani population. Here we show that ~250-1200 fold resistance to fenvalerate in populations of the species from northern and northwestern China is largely due to P450-based metabolism, and that CYP337B3v2 is also at high frequency in these populations but absent in a susceptible control strain. However we find little correlation between the level of resistance and CYP337B3v2 frequency, either across the resistant populations studied, or over time within them. While there is variation between populations in the levels of CYP337B3v2 expression, this is not correlated with the level of resistance either. These data suggest that much of the variation in the level of fenvalerate resistance in China is explained by P450s other than CYP337B3. We also find that both the level of resistance and CYP337B3v2 frequency decline in field populations transferred to the laboratory and remained there without fenvalerate exposure, suggesting a fitness cost to both characters in the absence of the pesticide pressure. However the declines in the two characters are not well correlated across populations, again consistent with a large contribution to the variation in resistance levels from factors other than CYP337B3. Copyright © 2014 Elsevier Inc. All rights reserved.

What is the most bothersome lower urinary tract symptom? Individual- and population-level perspectives for both men and women.

PubMed

Agarwal, Arnav; Eryuzlu, Leyla N; Cartwright, Rufus; Thorlund, Kristian; Tammela, Teuvo L J; Guyatt, Gordon H; Auvinen, Anssi; Tikkinen, Kari A O

2014-06-01

No study has compared the bothersomeness of all lower urinary tract symptoms (LUTS) using a population-based sample of adults. Despite this lack of evidence, investigators have often cited their LUTS of interest as the "most bothersome" or "one of the most bothersome." To compare the population- and individual-level burden of LUTS in men and women. In this population-based cross-sectional study, questionnaires were mailed to 6000 individuals (18-79 yr of age) randomly identified from the Finnish Population Register. The validated Danish Prostatic Symptom Score questionnaire was used for assessment of bother of 12 different LUTS. The age-standardized prevalence of at least moderate bother was calculated for each symptom (population-level burden). Among symptomatic individuals, the proportion of affected individuals with at least moderate bother was calculated for each symptom (individual-level bother). A total of 3727 individuals (62.4%) participated (53.7% female). The LUTS with the greatest population-level burden were urgency (7.9% with at least moderate bother), stress urinary incontinence (SUI) (6.5%), nocturia (6.0%), postmicturition dribble (5.8%), and urgency urinary incontinence (UUI) (5.0%). Burden from incontinence symptoms was higher in women than men, and the opposite was true for voiding and postmicturition symptoms. At the individual level, UUI was the most bothersome for both genders. Although the response proportion was high, approximately a third did not participate. Both men and women with UUI report moderate or major bother more frequently than individuals with other LUTS. At the population level, the most prevalent bothersome symptoms are urgency, SUI, and nocturia. Urinary urgency was the most common troubling symptom in a large population-based study; however, for individuals, urgency incontinence was the most likely to be rated as bothersome. Copyright © 2014 European Association of Urology. All rights reserved.

Decadal Changes in Ozone and Emissions in Central California and Current Issues

NASA Astrophysics Data System (ADS)

Tanrikulu, S.; Beaver, S.; Soong, S.; Tran, C.; Cordova, J.; Palazoglu, A.

2011-12-01

The relationships among ozone, emissions, and meteorology are very complex in central California, and must be well studied and understood in order to facilitate better air quality planning. Factors significantly impacting changes in emissions such as economic and population growth, and adopted emission controls make the matter even more complex. Here we review the history of ozone pollution in central California since the 1970s to plan for the future. Since the 1970s, changes in emissions have been accompanied by likewise dramatic changes in region-to-region differences in air quality. We focus on the coastal San Francisco Bay Area (SFBA) and the inland San Joaquin Valley (SJV). In the 1970s, the SFBA population was approaching 5 million people while the considerably larger and more rural SJV population remained below 2 million. The SFBA population was mostly confined to coastal locations. Peak ozone levels occurred mostly around the population centers and especially over the Bay itself. Hourly average ozone levels routinely approached 160 ppb. These high ozone levels promoted regulations under which SFBA emissions were continuously reduced through the present. By the 1990s, SFBA emissions had been reduced considerably despite the region's population growing to around 6 million. Relative to the 1970s, in 1990s the SFBA had lower peak ozone levels that were shifted to inland locations where much of the population growth was occurring. The SFBA still exceeded the federal 1-hour standard. A rapidly changing economic landscape in the 1970s promoted vast changes in the central California population distribution. In the SJV, the OPEC oil crisis promoted significant development of petroleum resources. Meanwhile, family farms were quickly being replaced with commercial-scale farming operations. The SJV population rapidly expanded to around 3 million people by the early 1990s. During this time, SJV emissions increased considerably, largely from increases in mobile source activities. The previously sparsely populated SJV had quickly developed an even more severe ozone problem than previous years. From 1990 to 2010, the SFBA population expanded to inland locations and then even further into the sheltered SJV. SFBA emissions for ROG and NOx were decreased around 40% and 15%, respectively during this period. High ozone levels became rather infrequent for coastal SFBA locations. During the same period, the SJV population continued to expand rapidly while emissions decreased, especially for ROG. Peak ozone levels remained around 100 ppb and shifted to locations downwind of Fresno and Bakersfield. Central California has experienced perhaps the most dramatic population growth and shifts in the United States during the contemporary economic era. These changes in population have led to some of the most difficult air quality management problems faced by regulators in the United States. Lessons learned from central California highlight the potential benefits of acting early and also the necessity for a long-term, flexible approach using sustained regulations to accompany population changes.

Initial characterisation of low and high seed dormancy populations of Lolium rigidum produced by repeated selection.

PubMed

Goggin, Danica E; Emery, R J Neil; Powles, Stephen B; Steadman, Kathryn J

2010-10-15

The physiological and biochemical bases of seed dormancy in Lolium rigidum (annual ryegrass) are largely unknown, and study of this process is complicated by the outcrossing nature of the species and the strong influence of environment on seed dormancy. In order to identify heritable biochemical factors contributing to seed dormancy in L. rigidum, seeds from a field-collected population were used to select sub-populations with consistently low or high seed dormancy over four generations. Low-dormancy seeds showed constitutive alpha-amylase activity prior to imbibition, higher concentrations of polyphenols and cis-zeatin, and lower abscisic acid and cis-zeatin riboside concentrations than high-dormancy seeds. Selection for high dormancy was associated with a reduction in response to dark-stratification for 21d at 20 degrees C (an effective means of releasing dormancy in the original, unselected population) over successive generations, but fluridone remained effective in breaking dormancy. Crossing of low- and high-dormancy populations indicated that dormancy level was not dependent upon the maternal genotype of the seed, and that the constitutive alpha-amylase activity and high seed anthocyanin concentrations characteristic of the low-dormancy populations were not correlated to high basal germination ability. Copyright (c) 2010 Elsevier GmbH. All rights reserved.

Childhood leukaemia in areas with different radon levels: a spatial and temporal analysis using GIS

PubMed Central

Kohli, S; Noorlind, B; Lofman, O

2000-01-01

OBJECTIVES—To evaluate the relation between exposure to ground radon levels and leukaemia among children using existing population and disease registers.
DESIGN—Ecological correlation study.
SETTING—The county of Östergötland in Sweden.
METHODS—Every child born in the county between 1979 and 1992 was mapped to the property centroid coordinates by linking addresses in the population and property registers. Population maps were overlaid with radon maps and exposure at birth and each subsequent year was quantified as high, normal, low or unknown. This was analysed with data from the tumour registry. Standardised mortality ratios (SMRs) were calculated using the age and sex specific rates for Sweden for the year 1995.
RESULTS—90 malignancies occurred among 53 146 children (498 887 person years) who formed the study population. SMRs for acute lymphatic leukaemia (ALL) among children born in high, normal and low risk areas were 1.43, 1.17 and 0.25 respectively. The relative risk for the normal risk group and high risk group as compared with the low risk group was 4.64 (95% CI 1.29, 28.26) and 5.67 (95% CI 1.06, 42.27). The association between ALL and continued residence at normal or high risk areas showed a similar trend. No association between radon risk levels and any other malignancy was seen.
CONCLUSION—Children born in and staying at areas where the risk from ground radon has been classified as low are less likely to develop ALL than those born in areas classified as normal and high risk.


Keywords: leukaemia; cancer; radon; ionising radiation; Geographic Information Systems PMID:11027195

The demand control model and circadian saliva cortisol variations in a Swedish population based sample (The PART study)

PubMed Central

Alderling, Magnus; Theorell, Töres; de la Torre, Bartolomé; Lundberg, Ingvar

2006-01-01

Background Previous studies of the relationship between job strain and blood or saliva cortisol levels have been small and based on selected occupational groups. Our aim was to examine the association between job strain and saliva cortisol levels in a population-based study in which a number of potential confounders could be adjusted for. Methods The material derives from a population-based study in Stockholm on mental health and its potential determinants. Two data collections were performed three years apart with more than 8500 subjects responding to a questionnaire in both waves. In this paper our analyses are based on 529 individuals who held a job, participated in both waves as well as in an interview linked to the second wave. They gave saliva samples at awakening, half an hour later, at lunchtime and before going to bed on a weekday in close connection with the interview. Job control and job demands were assessed from the questionnaire in the second wave. Mixed models were used to analyse the association between the demand control model and saliva cortisol. Results Women in low strain jobs (high control and low demands) had significantly lower cortisol levels half an hour after awakening than women in high strain (low control and high demands), active (high control and high demands) or passive jobs (low control and low demands). There were no significant differences between the groups during other parts of the day and furthermore there was no difference between the job strain, active and passive groups. For men, no differences were found between demand control groups. Conclusion This population-based study, on a relatively large sample, weakly support the hypothesis that the demand control model is associated with saliva cortisol concentrations. PMID:17129377

A case of isolation by distance and short-term temporal stability of population structure in brown trout (Salmo trutta) within the River Dart, southwest England

PubMed Central

Griffiths, Andrew M; Koizumi, Itsuro; Bright, Dylan; Stevens, Jamie R

2009-01-01

Salmonid fishes exhibit high levels of population differentiation. In particular, the brown trout (Salmo trutta L.) demonstrates complex within river drainage genetic structure. Increasingly, these patterns can be related to the underlying evolutionary models, of which three scenarios (member-vagrant hypothesis, metapopulation model and panmixia) facilitate testable predictions for investigations into population structure. We analysed 1225 trout collected from the River Dart, a 75 km long river located in southwest England. Specimens were collected from 22 sample sites across three consecutive summers (2001–2003) and genetic variation was examined at nine microsatellite loci. A hierarchical analysis of molecular variance revealed that negligible genetic variation was attributed among temporal samples. The highest levels of differentiation occurred among samples isolated above barriers to fish movement, and once these samples were removed, a significant effect of isolation-by-distance was observed. These results suggest that, at least in the short-term, ecological events are more important in shaping the population structure of Dart trout than stochastic extinction events, and certainly do not contradict the expectations of a member-vagrant hypothesis. Furthermore, individual-level spatial autocorrelation analyses support previous recommendations for the preservation of a number of spawning sites spaced throughout the tributary system to conserve the high levels of genetic variation identified in salmonid species. PMID:25567897

Genetic approaches to understanding the population-level impact of wind energy development on migratory bats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vonhof, Maarten J.; Russell, Amy L.

Documented fatalities of bats at wind turbines have raised serious concerns about the future impacts of increased wind power development on populations of migratory bat species. Yet there is little data on bat population sizes and trends to provide context for understanding the consequences of mortality due to wind power development. Using a large dataset of both nuclear and mitochondrial DNA variation for eastern red bats, we demonstrated that: 1) this species forms a single, panmictic population across their range with no evidence for the historical use of divergent migratory pathways by any portion of the population; 2) the effectivemore » size of this population is in the hundreds of thousands to millions; and 3) for large populations, genetic diversity measures and at least one coalescent method are insensitive to even very high rates of population decline over long time scales and until population size has become very small. Our data provide important context for understanding the population-level impacts of wind power development on affected bat species.« less

Knowledge on musculoskeletal diseases by the Spanish population.

PubMed

Lázaro, Pablo; Alfaro, Noelia; Méndez, José Ignacio; Garcia-Vicuña, Rosario; Jover, Juan Ángel; Sevilla, Jordi; Gabriele, Giovanna

2013-01-01

To explore knowledge on musculoskeletal-diseases (MSDs) by the Spanish population. This was a cross-sectional study of the general population (> 18 years) using a telephone survey of 1,009 subjects stratified by habitat size, age, sex, and geographic area. A structured questionnaire was used to collect information on the subjects, their general knowledge of MSDs (GK), their specific knowledge of particular MSDs (SK), and their knowledge of their social impact (KSI). Synthetic indicators of the level of knowledge were used to analyze, using univariate and multivariate models, variables associated to the level of knowledge. The KSI level ranges from medium-high (mean: 0.62 ± 0.16 out of 1), suggesting that most subjects recognize MSDs as disabling conditions which affect the ability to work and have a high personal and social cost. The GK level is intermediate (mean: 0.50 ± 0.17); 60% of subjects know something about MSDs, but 54% state that their information is poor/very poor. The SK level is low (mean: 0.18 ± 0.10), and there are some MSDs that are little known (lupus, spondylitis). Being male or retired or having a MSD is associated to a greater knowledge of MSDs. The Spanish population has a medium level of knowledge of the frequency and extent to which MSDs affect performance of activities by those who suffer them. They identify them adequately and have a GK of their symptoms, but have little information about them. The level of knowledge varies depending on social and demographic factors and on whether or not the subject has direct or indirect experience of what a MSD means. Copyright © 2012 Elsevier España, S.L. All rights reserved.

Concentrations of the urinary pyrethroid metabolite 3-phenoxybenzoic acid in farm worker families in the MICASA study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trunnelle, Kelly J., E-mail: kjtrunnelle@ucdavis.edu; Bennett, Deborah H.; Ahn, Ki Chang

Indoor pesticide exposure is a growing concern, particularly from pyrethroids, a commonly used class of pesticides. Pyrethroid concentrations may be especially high in homes of immigrant farm worker families who often live in close proximity to agricultural fields, and are faced with poor housing conditions, causing higher pest infestation and more pesticide use. We investigate exposure of farm worker families to pyrethroids in a study of mothers and children living in Mendota, CA within the population-based Mexican Immigration to California: Agricultural Safety and Acculturation (MICASA) Study. We present pyrethroid exposure based on an ELISA analysis of urinary metabolite 3-phenoxybenzoic acidmore » (3PBA) levels among 105 women and 103 children. The median urinary 3PBA levels (children=2.56 ug/g creatinine, mothers=1.46 ug/g creatinine) were higher than those reported in population based studies for the United States general population, but similar to or lower than studies with known high levels of pyrethroid exposure. A positive association was evident between poor housing conditions and the urinary metabolite levels, showing that poor housing conditions are a contributing factor to the higher levels of 3PBA seen in the urine of these farm worker families. Further research is warranted to fully investigate sources of exposure. - Highlights: • We investigate exposure of farm worker families to pyrethroids. • We present pyrethroid exposure based on an ELISA analysis of urinary 3PBA levels. • 3PBA levels were higher than those reported for the U.S. general population. • Poor housing conditions may be associated with pyrethroid exposure.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bright, Edward A.; Rose, Amy N.; Urban, Marie L.

The LandScan data set is a worldwide population database compiled on a 30" x 30" latitude/longitube grid. Census counts (at sub-national level) were apportioned to each grid cell based on likelihood coefficients, which are based on land cover, slope, road proximity, high-resolution imagery, and other data sets. The LandScan data set was developed as part of Oak Ridge National Laboratory (ORNL) Global Population Project for estimating ambient populations at risk.

Population Genetic Structure of Monimopetalum chinense (Celastraceae), an Endangered Endemic Species of Eastern China

PubMed Central

XIE, GUO-WEN; WANG, DE-LIAN; YUAN, YONG-MING; GE, XUE-JUN

2005-01-01

• Background and Aims Monimopetalum chinense (Celastraceae) standing for the monotypic genus is endemic to eastern China. Its conservation status is vulnerable as most populations are small and isolated. Monimopetalum chinense is capable of reproducing both sexually and asexually. The aim of this study was to understand the genetic structure of M. chinense and to suggest conservation strategies. • Methods One hundred and ninety individuals from ten populations sampled from the entire distribution area of M. chinense were investigated by using inter-simple sequence repeats (ISSR). • Key Results A total of 110 different ISSR bands were generated using ten primers. Low levels of genetic variation were revealed both at the species level (Isp = 0·183) and at the population level (Ipop = 0·083). High clonal diversity (D = 0·997) was found, and strong genetic differentiation among populations was detected (49·06 %). • Conclusions Small population size, possible inbreeding, limited gene flow due to short distances of seed dispersal, fragmentation of the once continuous range and subsequent genetic drift, may have contributed to shaping the population genetic structure of the species. PMID:15710646

Evaluating the effect of salinity on a simulated American Crocodile (Crocodylus acutus) population with applications to conservation and Everglades restoration

USGS Publications Warehouse

Richards, Paul M.; Mooij, Wolf M.; DeAngelis, Donald L.

2004-01-01

Everglades restoration will alter the hydrology of South Florida, affecting both water depth and salinity levels in the southern fringes of the Everglades, the habitat of the endangered American crocodile (Crocodylus acutus). A key question is what the effects of these hydrologic changes will be on the crocodile population. Reliable predictions of the viability of endangered species under a variety of management scenarios are of vital importance in conservation ecology. Juvenile American crocodiles are thought to be sensitive to high salinity levels, suffering reduced mass, and potentially reduced survivorship and recruitment. This could negatively impact the population recovery. We addressed the management issue of how the crocodile population will respond to alterations in hydrology with a spatially explicit individual-based model. The model is designed to relate water levels, salinities, and dominant vegetation to crocodile distribution, abundance, population growth, individual growth, survival, nesting effort, and nesting success. Our analysis shows that Everglades restoration, through its effects on water flow to estuaries, may benefit crocodile populations if increased freshwater flow reduces the chance that regional salinity levels exceed levels where small individuals lose mass. In addition, we conclude that conservation priority should be placed on reducing anthropogenic sources of mortality on large individuals, such as road mortality. Finally, research should focus on estimates of annual survivorship for large individuals.

Lower resistance and higher tolerance of invasive host plants: biocontrol agents reach high densities but exert weak control.

PubMed

Wang, Yi; Huang, Wei; Siemann, Evan; Zou, Jianwen; Wheeler, Gregory S; Carrillo, Juli; Ding, Jianqing

2011-04-01

Invasive plants often have novel biotic interactions in their introduced ranges. Their defense to herbivory may differ from their native counterparts, potentially influencing the effectiveness of biological control. If invasive plants have decreased resistance but increased tolerance to enemies, insect herbivores may rapidly build up their populations but exert weak control. Moreover, resource availability to plants may affect the efficacy of biological control agents. We tested these predictions using Chinese tallow tree (Triadica sebifera) and two specialist herbivores (Heterapoderopsis bicallosicollis and Gadirtha inexacta) that are candidates for biological control. We performed a pair of field common garden experiments in China in which Triadica seedlings from the native or introduced range were grown in low or high light conditions and subjected to different levels of herbivory by each herbivore in a factorial design. We found that Heterapoderopsis achieved greater densities on tallow trees from the introduced range or when trees were grown in high light conditions. When Gadirtha was raised in the lab on tallow tree foliage we found that it performed better (larger pupal size) when fed foliage from introduced populations. However, introduced populations generally had greater herbivore tolerance such that the impact of each agent on plant performance was lower than on native populations despite higher herbivore loads. Tallow trees grew more slowly and achieved smaller sizes in lower light levels, but the impact of biological control agents was comparable to that found for higher light levels. Plants from introduced populations grew larger than those from native populations in all conditions. Our results suggest that reduced resistance and increased tolerance to herbivory in introduced populations may impede success of biological control programs. Biological control practitioners should include plants from the introduced range in the prerelease evaluation, which will help predict insect impact on target weeds.

Genetic structure of the Common Eider in the western Aleutian Islands prior to fox eradication

USGS Publications Warehouse

Sonsthagen, Sarah A.; Talbot, Sandra L.; Wilson, Robert E.; Petersen, Margaret R.; Williams, Jeffrey C.; Byrd, G. Vernon; McCracken, Kevin G.

2013-01-01

Since the late 18th century bird populations residing in the Aleutian Archipelago have been greatly reduced by introduced arctic foxes (Alopex lagopus). We analyzed data from microsatellite, nuclear intron, and mitochondrial (mtDNA) loci to examine the spatial genetic structure, demography, and gene flow among four Aleutian Island populations of the Common Eider (Somateria mollissima) much reduced by introduced foxes. In mtDNA, we found high levels of genetic structure within and between island groups (ΦST = 0.643), but we found no population subdivision in microsatellites or nuclear introns. Differences in genetic structure between the mitochondrial and nuclear genomes are consistent with the Common Eider's breeding and winter biology, as females are highly philopatric and males disperse. Nevertheless, significant differences between islands in the mtDNA of males and marginal significance (P =0.07) in the Z-linked locus Smo 1 suggest that males may also have some level of fidelity to island groups. Severe reduction of populations by the fox, coupled with females' high philopatry, may have left the genetic signature of a bottleneck effect, resulting in the high levels of genetic differentiation observed in mtDNA (ΦST = 0.460–0.807) between islands only 440 km apart. Reestablishment of the Common Eider following the fox's eradication was likely through recruitment from within the islands and bolstered by dispersal from neighboring islands, as suggested by the lack of genetic structure and asymmetry in gene flow between Attu and the other Near Islands.

High intra-specific variation in avian body condition responses to climate limits generalisation across species

PubMed Central

van der Jeugd, Henk P.; van de Pol, Martijn

2018-01-01

It is generally assumed that populations of a species will have similar responses to climate change, and thereby that a single value of sensitivity will reflect species-specific responses. However, this assumption is rarely systematically tested. High intraspecific variation will have consequences for identifying species- or population-level traits that can predict differences in sensitivity, which in turn can affect the reliability of projections of future climate change impacts. We investigate avian body condition responses to changes in six climatic variables and how consistent and generalisable these responses are both across and within species, using 21 years of data from 46 common passerines across 80 Dutch sites. We show that body condition decreases with warmer spring/early summer temperatures and increases with higher humidity, but other climate variables do not show consistent trends across species. In the future, body condition is projected to decrease by 2050, mainly driven by temperature effects. Strikingly, populations of the same species generally responded just as differently as populations of different species implying that a single species signal is not meaningful. Consequently, species-level traits did not explain interspecific differences in sensitivities, rather population-level traits were more important. The absence of a clear species signal in body condition responses implies that generalisation and identifying species for conservation prioritisation is problematic, which sharply contrasts conclusions of previous studies on the climate sensitivity of phenology. PMID:29466460

Structure and genetic diversity of natural populations of Morus alba in the trans-Himalayan Ladakh region.

PubMed

Bajpai, Prabodh K; Warghat, Ashish R; Sharma, Ram Kumar; Yadav, Ashish; Thakur, Anil K; Srivastava, Ravi B; Stobdan, Tsering

2014-04-01

Sequence-related amplified polymorphism markers were used to assess the genetic structure in three natural populations of Morus alba from trans-Himalaya. Multilocation sampling was conducted across 14 collection sites. The overall genetic diversity estimates were high: percentage polymorphic loci 89.66%, Nei's gene diversity 0.2286, and Shannon's information index 0.2175. At a regional level, partitioning of variability assessed using analysis of molecular variance (AMOVA), revealed 80% variation within and 20% among collection sites. Pattern appeared in STRUCTURE, BARRIER, and AMOVA, clearly demonstrating gene flow between the Indus and Suru populations and a geographic barrier between the Indus-Suru and Nubra populations, which effectively hinders gene flow. The results showed significant genetic differentiation, population structure, high to restricted gene flow, and high genetic diversity. The assumption that samples collected from the three valleys represent three different populations does not hold true. The fragmentation present in trans-Himalaya was more natural and less anthropogenic.

Childhood lead poisoning prevention through prenatal housing inspection and remediation in St. Louis, MO.

PubMed

Berg, Daniel R; Eckstein, Erin T; Steiner, Matt S; Gavard, Jeffrey A; Gross, Gilad A

2012-03-01

We assessed the screening and remediation of home lead hazards prenatally in a high-risk population, hypothesizing that average blood-lead level and the number of poisonings would drop by 25%. One hundred fifty-two women underwent prenatal home inspections by certified lead inspectors. The hazards that were identified were remediated. The blood-lead levels of children of participating women were compared with matched control subjects. Blood-lead levels were obtained from 60 children and compared with matched control subjects. The average blood-lead level of children in the treatment group was 2.70 μg/dL vs 3.73 μg/dL in control subjects (P = .019). The percentage of children with levels >10 μg/dL in the treatment group was 0% vs 4.2% in control subjects (P = .128). Screening and remediation of houses of pregnant women is effective to reduce the average blood-lead level and number of children that exceed the federal level of concern for lead poisoning in a high-risk population. Copyright © 2012 Mosby, Inc. All rights reserved.

Cytochrome b sequences in black-crowned night-herons (Nycticorax nycticorax) from heronries exposed to genotoxic contaminants

USGS Publications Warehouse

Dahl, Christopher R.; Bickham, John W.; Wickliffe, Jeffery K.; Custer, Thomas W.

2001-01-01

DNA sequence analysis of a 215 base-pair region of the mitochondrial cytochrome b gene was used to examine genetic variation and search for evidence of an increased mutation rate in black-crowned night-herons. We examined five populations exposed to environmental contamination (primarily PAHs and PCBs) and one reference population from the eastern U.S. There was no evidence of a high mutation rate even within populations previously shown to exhibit increased variation in DNA content among somatic cells as a result of petroleum exposure. Three haplotypes were observed among 99 individuals. The low level of variability could be evidence for a genetic bottleneck, or that cytochrome b is too conservative for use in population genetic studies of this species. With the exception of one population from Louisiana, pair-wise Phist estimates were very low, indicative of little population structure and potentially high rates of effective migration among populations.

Population collapse to extinction: the catastrophic combination of parasitism and Allee effect.

PubMed

Hilker, Frank M

2010-01-01

Infectious diseases are responsible for the extinction of a number of species. In conventional epidemic models, the transition from endemic population persistence to extirpation takes place gradually. However, if host demographics exhibits a strong Allee effect (AE) (population decline at low densities), extinction can occur abruptly in a catastrophic population crash. This might explain why species suddenly disappear even when they used to persist at high endemic population levels. Mathematically, the tipping point towards population collapse is associated with a saddle-node bifurcation. The underlying mechanism is the simultaneous population size depression and the increase of the extinction threshold due to parasite pathogenicity and Allee effect. Since highly pathogenic parasites cause their own extinction but not that of their host, there can be another saddle-node bifurcation with the re-emergence of two endemic equilibria. The implications for control interventions are discussed, suggesting that effective management may be possible for ℛ(0)≫1.

SSR characterization of Oryza glumaepatula populations from the Brazilian Amazon and Cerrado biomes.

PubMed

Abreu, Aluana Gonçalves; Rosa, Thalita Marra; Borba, Tereza Cristina de Oliveira; Vianello, Rosana Pereira; Rangel, Paulo Hideo Nakano; Brondani, Claudio

2015-08-01

The level and distribution of the genetic variability in 18 natural populations of Oryza glumaepatula that were collected from two Brazilian states were estimated using a set of 23 highly informative SSR markers. Samples comprising 78 and 117 individuals from populations of the states of Tocantins and Roraima, respectively, were evaluated in order to integrate and support previous studies that were carried out with populations of O. glumaepatula from Brazil. A total of 189 alleles were identified with an average of 8.22 alleles per locus. The 11 populations from Roraima presented, in combination, a higher genetic diversity (HE = 0.245) compared with that of the seven populations from Tocantins (HE = 0.212). All of the populations showed high and significant inbreeding values (mean f = 0.59); however, the mean was higher in Tocantins populations, indicating a higher gene flow in Roraima populations. The overall coefficient of genetic differentiation (FST) among the populations was high and significant (0.59) and was higher in Tocantins due to the isolation of each population, in contrast to Roraima, where gene flow occurred more frequently. The SSR panel used in this work resulted to be informative (polymorphism information content = 0.201) for assessing genetic structure in O. glumaepatula populations.

Nitric oxide in adaptation to altitude

PubMed Central

Laskowski, Daniel; Erzurum, Serpil C.

2012-01-01

This review summarizes published information on levels of nitric oxide gas (NO) in the lungs and NO-derived liquid phase molecules in the acclimatization of visitors newly arrived at altitudes of 2500m or more and adaptation of populations whose ancestors arrived thousands of years ago. Studies of acutely exposed visitors to high altitude focus on the first 24–48 hours with just a few extending to days or weeks. Among healthy visitors, NO levels in the lung, plasma and/or red blood cells fell within three hours, but then returned toward baseline or slightly higher by 48 hours, and increased above baseline by 5 days. Among visitors ill with high-altitude pulmonary edema at the time of the study or in the past, NO levels were lower than their healthy counterparts. As for highland populations, Tibetans had NO levels in the lung, plasma and red blood cells that were at least double and in some cases orders of magnitude greater than other populations regardless of altitude. Red blood cell associated nitrogen oxides were more than two hundred times higher. Other highland populations had generally higher levels although not to the degree showed by Tibetans. Overall, responses of those acclimatized and those presumed to be adapted are in the same direction although the Tibetans have much larger responses. Missing are long-term data on lowlanders at altitude showing how similar they become to the Tibetan phenotype. Also missing are data on Tibetans at low altitude to see the extent to which their phenotype is a response to the immediate environment or expressed constitutively. The mechanisms causing the visitors’ and the Tibetans’ high levels of NO and NO-derived molecules at altitude remain unknown. Limited data suggest processes including hypoxic upregulation of NO synthase gene expression, hemoglobin-NO reactions and genetic variation. Gains in understanding will require integrating appropriate methods and measurement techniques with indicators of adaptive function under hypoxic stress. PMID:22300645

Population genetics of Schistosoma japonicum within the Philippines suggest high levels of transmission between humans and dogs.

PubMed

Rudge, James W; Carabin, Hélène; Balolong, Ernesto; Tallo, Veronica; Shrivastava, Jaya; Lu, Da-Bing; Basáñez, María-Gloria; Olveda, Remigio; McGarvey, Stephen T; Webster, Joanne P

2008-01-01

Schistosoma japonicum, which remains a major public health problem in the Philippines and mainland China, is the only schistosome species for which zoonotic transmission is considered important. While bovines are suspected as the main zoonotic reservoir in parts of China, the relative contributions of various non-human mammals to S. japonicum transmission in the Philippines remain to be determined. We examined the population genetics of S. japonicum in the Philippines in order to elucidate transmission patterns across host species and geographic areas. S. japonicum miracidia (hatched from eggs within fecal samples) from humans, dogs, pigs and rats, and cercariae shed from snail-intermediate hosts, were collected across two geographic areas of Samar Province. Individual isolates were then genotyped using seven multiplexed microsatellite loci. Wright's F(ST) values and phylogenetic trees calculated for parasite populations suggest a high frequency of parasite gene-flow across definitive host species, particularly between dogs and humans. Parasite genetic differentiation between areas was not evident at the definitive host level, possibly suggesting frequent import and export of infections between villages, although there was some evidence of geographic structuring at the snail-intermediate host level. These results suggest very high levels of transmission across host species, and indicate that the role of dogs should be considered when planning control programs. Furthermore, a regional approach to treatment programs is recommended where human migration is extensive.

Stress, mental health, and job performance among active duty military personnel: findings from the 2002 Department of Defense Health-Related Behaviors Survey.

PubMed

Hourani, Laurel L; Williams, Thomas V; Kress, Amii M

2006-09-01

This study examined the extent to which high levels of occupational and family stress were associated with mental health problems and productivity loss among active duty military personnel. We analyzed data from the 2002 Department of Defense Survey of Health-Related Behaviors among Military Personnel, which provided extensive population-based information on 12,756 active duty personnel in all branches of the military worldwide. Military personnel reported higher levels of stress at work than in their family life. The personnel reporting the highest levels of occupational stress were those 25 or younger, those who were married with spouses not present, and women. Personnel with high levels of stress had significantly higher rates of mental health problems and productivity loss than those with less stress. We recommend that prevention and intervention efforts geared toward personnel reporting the highest levels of stress be given priority for resources in this population.

Molecular evidence for a founder effect in invasive house finch (Carpodacus mexicanus) populations experiencing an emergent disease epidemic.

PubMed

Hawley, Dana M; Hanley, Daniel; Dhondt, André A; Lovette, Irby J

2006-01-01

The impact of founder events on levels of genetic variation in natural populations remains a topic of significant interest. Well-documented introductions provide a valuable opportunity to examine how founder events influence genetic diversity in invasive species. House finches (Carpodacus mexicanus) are passerine birds native to western North America, with the large eastern North American population derived from a small number of captive individuals released in the 1940s. Previous comparisons using amplified fragment length polymorphism (AFLP) markers found equivalent levels of diversity in eastern and western populations, suggesting that any genetic effects of the founder event were ameliorated by the rapid growth of the newly established population. We used an alternative marker system, 10 highly polymorphic microsatellites, to compare levels of genetic diversity between four native and five introduced house finch populations. In contrast to the AFLP comparisons, we found significantly lower allelic richness and heterozygosity in introduced populations across all loci. Three out of five introduced populations showed significant reductions in the ratio of the number of alleles to the allele size range, a within-population characteristic of recent bottlenecks. Finally, native and introduced populations showed significant pairwise differences in allele frequencies in every case, with stronger isolation by distance within the introduced than native range. Overall, our results provide compelling molecular evidence for a founder effect during the introduction of eastern house finches that reduced diversity levels at polymorphic microsatellite loci and may have contributed to the emergence of the Mycoplasma epidemic which recently swept the eastern range of this species.

The UK population: how does it compare?

PubMed

Matheson, Jil

2010-01-01

This is the fourth demographic report for the UK, providing an overview of the latest statistics on the population. This year's article compares the UK with other European countries and a range of nations from around the world. Statistical comparisons are made for fertility, mortality, ageing, migration and population density. The UK has an ageing population, but one that is not ageing as rapidly as some other countries such as Germany, Italy and Japan. Although life expectation in the UK is improving in line with most western European countries, relatively high levels of fertility ensure that the proportion of the population that is young remains high. Around one in ten residents of the UK are foreign born, a lower proportion than many developed countries. UK population density has increased steadily and is the fourth highest in the EU.

Areas with High Rates of Police-Reported Violent Crime Have Higher Rates of Childhood Asthma Morbidity.

PubMed

Beck, Andrew F; Huang, Bin; Ryan, Patrick H; Sandel, Megan T; Chen, Chen; Kahn, Robert S

2016-06-01

To assess whether population-level violent (and all) crime rates were associated with population-level child asthma utilization rates and predictive of patient-level risk of asthma reutilization after a hospitalization. A retrospective cohort study of 4638 pediatric asthma-related emergency department visits and hospitalizations between 2011 and 2013 was completed. For population-level analyses, census tract asthma utilization rates were calculated by dividing the number of utilization events within a tract by the child population. For patient-level analyses, hospitalized patients (n = 981) were followed until time of first asthma-related reutilization. The primary predictor was the census tract rate of violent crime as recorded by the police; the all crime (violent plus nonviolent) rate was also assessed. Census tract-level violent and all crime rates were significantly correlated with asthma utilization rates (both P < .0001). The violent crime rate explained 35% of the population-level asthma utilization variance and remained associated with increased utilization after adjustment for census tract poverty, unemployment, substandard housing, and traffic exposure (P = .002). The all crime rate explained 28% of the variance and was similarly associated with increased utilization after adjustment (P = .02). Hospitalized children trended toward being more likely to reutilize if they lived in higher violent (P = .1) and all crime areas (P = .01). After adjustment, neither relationship was significant. Crime data could help facilitate early identification of potentially toxic stressors relevant to the control of asthma for populations and patients. Copyright © 2016 Elsevier Inc. All rights reserved.

Areas with high rates of police-reported violent crime have higher rates of childhood asthma morbidity

PubMed Central

Beck, Andrew F.; Huang, Bin; Ryan, Patrick H.; Sandel, Megan T.; Chen, Chen; Kahn, Robert S.

2016-01-01

Objectives To assess whether population-level violent (and all) crime rates were associated with population-level child asthma utilization rates and predictive of patient-level risk of asthma reutilization after a hospitalization. Study design A retrospective cohort study of 4,638 pediatric asthma-related emergency department visits and hospitalizations between 2011 and 2013 was completed. For population-level analyses, census tract asthma utilization rates were calculated by dividing the number of utilization events within a tract by the child population. For patient-level analyses, hospitalized patients (n=981) were followed until time of first asthma-related reutilization. The primary predictor was the census tract rate of violent crime as recorded by the police; the all crime (violent plus non-violent) rate was also assessed. Results Census tract-level violent and all crime rates were significantly correlated with asthma utilization rates (both p<.0001). The violent crime rate explained 35% of the population-level asthma utilization variance and remained associated with increased utilization after adjustment for census tract poverty, unemployment, substandard housing, and traffic exposure (p=.002). The all crime rate explained 28% of the variance and was similarly associated with increased utilization after adjustment (p=.02). Hospitalized children trended toward being more likely to reutilize if they lived in higher violent (p=.1) and all crime areas (p=.01). After adjustment, neither relationship was significant. Conclusions Crime data could help facilitate early identification of potentially toxic stressors relevant to the control of asthma for populations and patients. PMID:26960918

Cost-benefit analyses of supplementary measles immunisation in the highly immunized population of New Zealand.

PubMed

Hayman, D T S; Marshall, J C; French, N P; Carpenter, T E; Roberts, M G; Kiedrzynski, T

2017-09-05

As endemic measles is eliminated from countries through increased immunisation, the economic benefits of enhanced immunisation programs may come into question. New Zealand has suffered from outbreaks after measles introductions from abroad and we use it as a model system to understand the benefits of catch up immunisation in highly immunised populations. We provide cost-benefit analyses for measles supplementary immunisation in New Zealand. We model outbreaks based on estimates of the basic reproduction number in the vaccinated population (R v , the number of secondary infections in a partially immunised population), based on the number of immunologically-naïve people at district and national levels, considering both pre- and post-catch up vaccination scenarios. Our analyses suggest that measles R v often includes or exceeds one (0.18-3.92) despite high levels of population immunity. We calculate the cost of the first 187 confirmed and probable measles cases in 2014 to be over NZ$1 million (∼US$864,200) due to earnings lost, case management and hospitalization costs. The benefit-cost ratio analyses suggest additional vaccination beyond routine childhood immunisation is economically efficient. Supplemental vaccination-related costs are required to exceed approximately US$66 to US$1877 per person, depending on different scenarios, before supplemental vaccination is economically inefficient. Thus, our analysis suggests additional immunisation beyond childhood programs to target naïve individuals is economically beneficial even when childhood immunisation rates are high. Copyright © 2017 Elsevier Ltd. All rights reserved.

Sun exposure profile in the French population. Results of the EDIFICE Melanoma survey.

PubMed

Sassolas, B; Grange, F; Touboul, C; Lebbe, C; Saiag, P; Mortier, L; Lhomel, C; Robert, C

2015-02-01

The incidence of melanoma is increasing worldwide, causing significant economic burden at community and individual levels. Ultraviolet radiation, from natural sunlight or artificial sources, is the main environmental, modifiable risk factor for melanoma. The present analysis assesses the profile of sun exposure in the French population as well as the level of awareness about ultraviolet risk and protection. The survey was conducted via telephone interviews in September and October 2011. In total, 1502 respondents were questioned about their own sun exposure with the question "do you ever, even occasionally, spend time in the sun, during leisure-time, vacation or your professional occupation?" They were also asked about sun protection measures used: protective clothing, a hat or sunscreen. More than three respondents out of four (78%) declared exposing themselves to the sun, with an average of 113 days per year. Of these, 38% did not use appropriate sun protection measures. We identified the following characteristics of individuals declaring high sun exposure: chiefly men under the age of 40, higher socio-professional levels, and adults with no children. Individuals who make a poor use of protective measures are mostly men and of low educational levels. Individuals declaring low sun exposure were chiefly: women, individuals over the age of 60, and those with no professional activity. The high sun protection population comprises mostly: women, higher socio-professional levels, with no specific age-group profile. Analysis of the EDIFICE Melanoma survey provides information about the attitudes of the French population towards sun exposure. The most frequent contexts of sun exposure and the associated socio-demographic characteristics of the population with at-risk attitudes regarding sun exposure are identified. This deeper insight into the profile of at-risk populations will allow interventions to be more accurately targeted, thus potentially improving public health benefits. © 2015 European Academy of Dermatology and Venereology.

Dietary intake of cadmium from Bangladeshi foods.

PubMed

Al-Rmalli, S W; Jenkins, R O; Haris, P I

2012-01-01

Human exposure to cadmium (Cd) is associated with various diseases and high levels of Cd have been detected in Bangladeshi population warranting further research to identify the source of this exposure. In this study, Cd levels in 327 and 94 samples of Bangladeshi food and non-food samples, respectively, were determined using inductively coupled plasma mass spectrometry. This is the largest number of Bangladeshi food and nonfood samples investigated for their Cd content. High Cd levels were detected in leafy vegetables (mean 31 [SD 29]μg/kg). Of these vegetables, lal shak (Amaranthus tricolor) contained the highest Cd level (303 μg/kg [wet weight]; mean 100.5 [SD 95]μg/kg). Bangladeshi rice also showed significant concentration of Cd (mean 37.2 [SD 30]μg/kg). Of particular concern is the very high level of Cd detected in some puffed rice, which we attribute to the illegal practice of using urea for whitening the puffed rice. Tobacco leaves, which are commonly consumed during betel quid chewing by Bangladeshis, contain significant levels of Cd (mean 95 [SD 87]μg/kg). The total daily intake (TDI) of Cd from foods for Bangladeshis was estimated to be 34.55 μg/d. This is rather high when compared to the TDI of Cd for other populations. Our analysis reveals that this is mainly due to the very high intake of rice and vegetables, and lower consumption of animal products (which are low in Cd), by the Bangladeshis. We also determined the provisional maximum tolerable daily intake and target hazard quotients values for Cd. Clearly a more balanced diet is necessary to reduce the Cd intake in the Bangladeshi population, especially by reducing the very high intake of rice and certain leafy vegetables. Food manufacturing and agricultural practices needs to be altered to reduce the entry of Cd into the food chain. Exposure to high levels of Cd can be harmful to human health and this study provides a comprehensive analysis of Cd levels in a variety of food items from Bangladesh. The findings are of particular importance to consumers of Bangladeshi foods in both Bangladesh and in other countries. Data obtained will be valuable resources for food safety and regulatory bodies as our study suggests entry of Cd in foods through use of illegal chemicals in food manufacturing processes. © 2011 Institute of Food Technologists®

A summary analysis of the 3rd inquiry.

PubMed

1977-01-01

20 ESCAP member countries responded to the "Third Population Inquiry among Governments: Population policies in the context of development in 1976." The questionnaire sent to the member countries covered economic and social development and population growth, mortality, fertility and family formation, population distribution and internal migration, international migration, population data collection and research, training, and institutional arrangements for the formulation of population policies within development. Most of the governments in the ESCAP region that responded indicate that the present rate of population growth constrains their social and economic development. Among the governments that consider the present rate of population growth to constrain economic and social development, 13 countries regarded the most appropriate response to the constraint would include an adjustment of both socioeconomic and demographic factors. 11 of the governments regarded their present levels of average life expectancy at birth "acceptable" and 7 identified their levels as "unacceptable." Most of the governments who responded consider that, in general, their present level of fertility is too high and constrains family well-being. Internal migration and population distribution are coming to be seen as concerns for government population policy. The most popular approaches to distributing economic and social activities are rural development, urban and regional development and industrial dispersion. There was much less concern among the governments returning the questionnaire about the effect of international migration than internal migration on social and economic development.

Potential impact of harvesting on the population dynamics of two epiphytic bromeliads

NASA Astrophysics Data System (ADS)

Toledo-Aceves, Tarin; Hernández-Apolinar, Mariana; Valverde, Teresa

2014-08-01

Large numbers of epiphytes are extracted from cloud forests for ornamental use and illegal trade in Latin America. We examined the potential effects of different harvesting regimes on the population dynamics of the epiphytic bromeliads Tillandsia multicaulis and Tillandsia punctulata. The population dynamics of these species were studied over a 2-year period in a tropical montane cloud forest in Veracruz, Mexico. Prospective and retrospective analyses were used to identify which demographic processes and life-cycle stages make the largest relative contribution to variation in population growth rate (λ). The effect of simulated harvesting levels on population growth rates was analysed for both species. λ of both populations was highly influenced by survival (stasis), to a lesser extent by growth, and only slightly by fecundity. Vegetative growth played a central role in the population dynamics of these organisms. The λ value of the studied populations did not differ significantly from unity: T. multicaulis λ (95% confidence interval) = 0.982 (0.897-1.060) and T. punctulata λ = 0.967 (0.815-1.051), suggesting population stability. However, numerical simulation of different levels of extraction showed that λ would drop substantially even under very low (2%) harvesting levels. Matrix analysis revealed that T. multicaulis and T. punctulata populations are likely to decline and therefore commercial harvesting would be unsustainable. Based on these findings, management recommendations are outlined.

Differential Fertility, Intergenerational Educational Mobility, and Racial Inequality.

ERIC Educational Resources Information Center

Mare, Robert D.

Recent commentary has suggested that the relatively high fertility of poorly educated women tends to dampen the average intellectual qualifications of the population. To evaluate this claim requires a model of population growth that takes account of fertility differences among women with varying levels of educational attainment and patterns of…

Development of the Juvenile Justice Anger Management Treatment for Girls

ERIC Educational Resources Information Center

Goldstein, Naomi E. S.; Serico, Jennifer M.; Riggs Romaine, Christina L.; Zelechoski, Amanda D.; Kalbeitzer, Rachel; Kemp, Kathleen; Lane, Christy

2013-01-01

Female juvenile offenders exhibit high levels of anger, relational aggression, and physical aggression, but the population has long been ignored in research and practice. No anger management treatments have been developed specifically for this population, and no established anger management treatments are empirically supported for use with…

Relationship between educational and occupational levels, and Chronic Kidney Disease in a multi-ethnic sample- The HELIUS study.

PubMed

Adjei, David N; Stronks, Karien; Adu, Dwomoa; Snijder, Marieke B; Modesti, Pietro A; Peters, Ron J G; Vogt, Liffert; Agyemang, Charles

2017-01-01

Ethnic minority groups in high-income countries are disproportionately affected by Chronic Kidney Disease (CKD) for reasons that are unclear. We assessed the association of educational and occupational levels with CKD in a multi-ethnic population. Furthermore, we assessed to what extent ethnic inequalities in the prevalence of CKD were accounted for by educational and occupational levels. Cross-sectional analysis of baseline data from the Healthy Life in an Urban Setting (HELIUS) study of 21,433 adults (4,525 Dutch, 3,027 South-Asian Surinamese, 4,105 African Surinamese, 2,314 Ghanaians, 3,579 Turks, and 3,883 Moroccans) aged 18 to 70 years living in Amsterdam, the Netherlands. Three CKD outcomes were considered using the 2012 KDIGO (Kidney Disease: Improving Global Outcomes) severity of CKD classification. Comparisons between educational and occupational levels were made using logistic regression analyses. After adjustment for sex and age, low-level and middle-level education were significantly associated with higher odds of high to very high-risk of CKD in Dutch (Odds Ratio (OR) 2.10, 95% C.I., 1.37-2.95; OR 1.55, 95% C.I., 1.03-2.34). Among ethnic minority groups, low-level education was significantly associated with higher odds of high to very-high-risk CKD but only in South-Asian Surinamese (OR 1.58, 95% C.I., 1.06-2.34). Similar results were found for the occupational level in relation to CKD risk. The lower educational and occupational levels of ethnic minority groups partly accounted for the observed ethnic inequalities in CKD. Reducing CKD risk in ethnic minority populations with low educational and occupational levels may help to reduce ethnic inequalities in CKD and its related complications.

High molecular diversity in the true service tree (Sorbus domestica) despite rareness: data from Europe with special reference to the Austrian occurrence.

PubMed

George, Jan-Peter; Konrad, Heino; Collin, Eric; Thevenet, Jean; Ballian, Dalibor; Idzojtic, Marilena; Kamm, Urs; Zhelev, Peter; Geburek, Thomas

2015-06-01

Sorbus domestica (Rosaceae) is one of the rarest deciduous tree species in Europe and is characterized by a scattered distribution. To date, no large-scale geographic studies on population genetics have been carried out. Therefore, the aims of this study were to infer levels of molecular diversity across the major part of the European distribution of S. domestica and to determine its population differentiation and structure. In addition, spatial genetic structure was examined together with the patterns of historic and recent gene flow between two adjacent populations. Leaf or cambium samples were collected from 17 populations covering major parts of the European native range from north-west France to south-east Bulgaria. Seven nuclear microsatellites and one chloroplast minisatellite were examined and analysed using a variety of methods. Allelic richness was unexpectedly high for both markers within populations (mean per locus: 3·868 for nSSR and 1·647 for chloroplast minisatellite). Moreover, there was no evidence of inbreeding (mean Fis = -0·047). The Italian Peninsula was characterized as a geographic region with comparatively high genetic diversity for both genomes. Overall population differentiation was moderate (FST = 0·138) and it was clear that populations formed three groups in Europe, namely France, Mediterranean/Balkan and Austria. Historic gene flow between two local Austrian populations was high and asymmetric, while recent gene flow seemed to be disrupted. It is concluded that molecular mechanisms such as self-incompatibility and high gene flow distances are responsible for the observed level of allelic richness as well as for population differentiation. However, human influence could have contributed to the present genetic pattern, especially in the Mediterranean region. Comparison of historic and recent gene flow may mirror the progress of habitat fragmentation in eastern Austria. © The Author 2015. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Stochastic evolutionary dynamics in minimum-effort coordination games

NASA Astrophysics Data System (ADS)

Li, Kun; Cong, Rui; Wang, Long

2016-08-01

The minimum-effort coordination game draws recently more attention for the fact that human behavior in this social dilemma is often inconsistent with the predictions of classical game theory. Here, we combine evolutionary game theory and coalescence theory to investigate this game in finite populations. Both analytic results and individual-based simulations show that effort costs play a key role in the evolution of contribution levels, which is in good agreement with those observed experimentally. Besides well-mixed populations, set structured populations have also been taken into consideration. Therein we find that large number of sets and moderate migration rate greatly promote effort levels, especially for high effort costs.

A vegetarian diet does not protect against nonalcoholic fatty liver disease (NAFLD): A cross-sectional study between Buddhist priests and the general population.

PubMed

Choi, Sung Hun; Oh, Dong Jun; Kwon, Ki Hwan; Lee, Jun Kyu; Koh, Moon Soo; Lee, Jin Ho; Kang, Hyoun Woo

2015-07-01

There is limited data that supports a role for a vegetarian diet in nonalcoholic fatty liver disease (NAFLD). The aim of this study is to evaluate the relationship between vegetarian diets and NAFLD, considering metabolic syndrome and obesity. This is a cross-sectional, retrospective study comparing the prevalence of NAFLD of 615 Buddhist priests and age-, sex-, Body mass index (BMI)-and presence/absence of metabolic syndrome-matched controls who underwent routine health checkups in a health promotion center. Diagnosis and severity of NAFLD was determined based on ultrasonographic findings. The prevalence of NAFLD was not statistically significantly different between the Buddhist priests and the general population (29.9% vs. 25.05%, p=0.055). The Buddhist priest group had higher serum albumin, serum aspartate aminotransferase (AST), serum alanine aminotransferase (ALT), and serum triglyceride levels and lower serum total bilirubin, serum fasting glucose, and serum high density lipoprotein (HDL) levels than the general population group. In univariate analysis and multivariate analysis, NAFLD was associated with old age, male gender, increased BMI, increased waist circumference, metabolic syndrome, high albumin, high glucose, high AST, high ALT, high gamma glutamyl transpeptidase (GGT), high triglycerides, low HDL, high low density lipoprotein (LDL), and high total cholesterol. The vegetarian diet does not protect against NAFLD.

Circumpolar contaminant concentrations in polar bears (Ursus maritimus) and potential population-level effects.

PubMed

Nuijten, R J M; Hendriks, A J; Jenssen, B M; Schipper, A M

2016-11-01

Polar bears (Ursus maritimus) currently receive much attention in the context of global climate change. However, there are other stressors that might threaten the viability of polar bear populations as well, such as exposure to anthropogenic pollutants. Lipophilic organic compounds bio-accumulate and bio-magnify in the food chain, leading to high concentrations at the level of top-predators. In Arctic wildlife, including the polar bear, various adverse health effects have been related to internal concentrations of commercially used anthropogenic chemicals like PCB and DDT. The extent to which these individual health effects are associated to population-level effects is, however, unknown. In this study we assembled data on adipose tissue concentrations of ∑PCB, ∑DDT, dieldrin and ∑PBDE in individual polar bears from peer-reviewed scientific literature. Data were available for 14 out of the 19 subpopulations. We found that internal concentrations of these contaminants exceed threshold values for adverse individual health effects in several subpopulations. In an exploratory regression analysis we identified a clear negative correlation between polar bear population density and sub-population specific contaminant concentrations in adipose tissue. The results suggest that adverse health effects of contaminants in individual polar bears may scale up to population-level consequences. Our study highlights the need to consider contaminant exposure along with other threats in polar bear population viability analyses. Copyright © 2016 Elsevier Inc. All rights reserved.

Concerted evolution at the population level: pupfish HindIII satellite DNA sequences.

PubMed Central

Elder, J F; Turner, B J

1994-01-01

The canonical monomers (approximately 170 bp) of an abundant (1.9 x 10(6) copies per diploid genome) satellite DNA sequence family in the genome of Cyprinodon variegatus, a "pupfish" that ranges along the Atlantic coast from Cape Cod to central Mexico, are divergent in base sequence in 10 of 12 samples collected from natural populations. The divergence involves substitutions, deletions, and insertions, is marked in scope (mean pairwise sequence similarity = 61.6%; range = 35-95.9%), is largely confined to the 3' half of the monomer, and is not correlated with the distance among collecting sites. Repetitive cloning and direct genomic sequencing experiments failed to detect intrapopulation and intraindividual variation, suggesting high levels of sequence homogeneity within populations. The satellite sequence has therefore undergone "concerted evolution," at the level of the local population. Concerted evolution has previously almost always been discussed in terms of the divergence of species or higher taxa; its intraspecific occurrence apparently has not been reported previously. The generality of the observation is difficult to evaluate, for although satellite DNAs from a large number of organisms have been studied in detail, there appear to be little or no other data on their sequence variation in natural populations. The relationship (if any) between concerted, population level, satellite DNA divergence and the extent of gene flow/genetic isolation among conspecific natural populations remains to be established. Images PMID:8302879

Specific Abilities May Increment Psychometric g for High Ability Populations

DTIC Science & Technology

2016-04-14

tend to sort themselves into jobs that are commensurate with their ability level ( McCormick , DeNisi, & Staw, 1979; McCormick , Jeanneret, & Mecham...of Genetic Psychology, 153, 229-230. Specific abilities, g, & high ability populations 14 McCormick , E. J., DeNisi, A. S., & Shaw, J. B... McCormick , E. J., Jeanneret, P. R., & Mecham, R. C. (1972). A study of job characteristics and job dimensions as based on the Position Analysis Questionnaire

The Effects of Blood Alcohol Levels on Driving Variables in a High-Risk Population: Objective and Subjective Measures.

ERIC Educational Resources Information Center

Cox, Daniel J.; And Others

1995-01-01

Assessed high-risk individuals' subjective awareness of legal intoxication and ability to drive, and objectively quantified their blood alcohol levels and driving performance. While subjects were able to recognize legal intoxication, one-third of the subjects were still willing to drive after becoming intoxicated beyond the legal limit to drive.…

Population dynamics of aberrant chromosome 1 in mice.

PubMed

Sabantsev, I; Spitsin, O; Agulnik, S; Ruvinsky, A

1993-05-01

Natural populations of two semispecies of house mouse, Mus musculus domesticus and M.m. musculus, were found to be polymorphic for an aberrant chromosome 1 bearing a large inserted block of homogeneously staining heterochromatin. Strong meiotic drive for the aberrant chromosome from M.m. musculus was previously observed in heterozygous female mice. There are at least three meiotic drive levels determined by different allelic variants of distorter. Homozygotes had low viability and females showed low fertility. Both homo- and heterozygous males had normal fertility and their segregation patterns did not deviate from normal. Computer simulations were performed of the dynamics of aberrant chromosome 1 in demes and populations. The data demonstrate that a spontaneous mutation (inversion) of an aberrant chromosome 1, once arisen, has a high probability of spreading in a population at high coefficients of meiotic drive and migration. In the long-term, the population attains a stationary state which is determined by the drive level and migration intensity. The state of stable genotypic equilibrium is independent of deme and population size, as well as of the initial concentration of the aberrant chromosome. As populations initially polymorphic for the distorters approach the stationary state, the stronger distorter is eliminated. The frequencies of the aberrant chromosome determined by computer analysis agree well with those obtained for the studied Asian M.m. musculus populations. The evolutionary pathways for the origin and fixation of the aberrant chromosome in natural populations are considered.

PCR-RFLP analysis of mitochondrial DNA cytochrome b gene among Haruan (Channa striatus) in Malaysia.

PubMed

Rahim, Mohamamd Hafiz Abdul; Ismail, Patimah; Alias, Rozila; Muhammad, Norwati; Mat Jais, Abdul Manan

2012-02-15

Haruan (Channa striatus) is in great demand in the Malaysian domestic fish market. In the present study, mtDNA cyt b was used to investigate genetic variation of C. striatus among populations in Peninsular Malaysia. The overall population of C. striatus demonstrated a high level of haplotype diversity (h) and a low-to-moderate level of nucleotide diversity (π). Analysis of molecular variance (AMOVA) results showed a significantly different genetic differentiation among 6 populations (F(ST)=0.37566, P=0.01). Gene flow (Nm) was high and ranged from 0.32469 to infinity (∞). No significant relationship between genetic distance and geographic distance was detected. A UPGMA tree based on the distance matrix of net interpopulation nucleotide divergence (d(A)) and haplotype network of mtDNA cyt b revealed that C. striatus is divided into 2 major clades. The neutrality and mismatch distribution tests for all populations suggested that C. striatus in the study areas had undergone population expansion. The estimated time of population expansion in the mtDNA cyt b of C. striatus populations occurred 0.72-6.19 million years ago. Genetic diversity of mtDNA cyt b and population structure among Haruan populations in Peninsular Malaysia will be useful in fisheries management for standardization for Good Agriculture Practices (GAP) in fish-farming technology, as well as providing the basis for Good Manufacturing Practices (GMP). Copyright © 2011 Elsevier B.V. All rights reserved.

Serum magnesium is associated with the risk of dementia.

PubMed

Kieboom, Brenda C T; Licher, Silvan; Wolters, Frank J; Ikram, M Kamran; Hoorn, Ewout J; Zietse, Robert; Stricker, Bruno H; Ikram, M Arfan

2017-10-17

To determine if serum magnesium levels are associated with the risk of all-cause dementia and Alzheimer disease. Within the prospective population-based Rotterdam Study, we measured serum magnesium levels in 9,569 participants, free from dementia at baseline (1997-2008). Participants were subsequently followed up for incident dementia, determined according to the DSM-III-R criteria, until January 1, 2015. We used Cox proportional hazard regression models to associate quintiles of serum magnesium with incident all-cause dementia. We used the third quintile as a reference group and adjusted for age, sex, Rotterdam Study cohort, educational level, cardiovascular risk factors, kidney function, comorbidities, other electrolytes, and diuretic use. Our study population had a mean age of 64.9 years and 56.6% were women. During a median follow-up of 7.8 years, 823 participants were diagnosed with all-cause dementia. Both low serum magnesium levels (≤0.79 mmol/L) and high serum magnesium levels (≥0.90 mmol/L) were associated with an increased risk of dementia (hazard ratio [HR] 1.32, 95% confidence interval [CI] 1.02-1.69, and HR 1.30, 95% CI 1.02-1.67, respectively). Both low and high serum magnesium levels are associated with an increased risk of all-cause dementia. Our results warrant replication in other population-based studies. © 2017 American Academy of Neurology.

Urban-hazard risk analysis: mapping of heat-related risks in the elderly in major Italian cities.

PubMed

Morabito, Marco; Crisci, Alfonso; Gioli, Beniamino; Gualtieri, Giovanni; Toscano, Piero; Di Stefano, Valentina; Orlandini, Simone; Gensini, Gian Franco

2015-01-01

Short-term impacts of high temperatures on the elderly are well known. Even though Italy has the highest proportion of elderly citizens in Europe, there is a lack of information on spatial heat-related elderly risks. Development of high-resolution, heat-related urban risk maps regarding the elderly population (≥ 65). A long time-series (2001-2013) of remote sensing MODIS data, averaged over the summer period for eleven major Italian cities, were downscaled to obtain high spatial resolution (100 m) daytime and night-time land surface temperatures (LST). LST was estimated pixel-wise by applying two statistical model approaches: 1) the Linear Regression Model (LRM); 2) the Generalized Additive Model (GAM). Total and elderly population density data were extracted from the Joint Research Centre population grid (100 m) from the 2001 census (Eurostat source), and processed together using "Crichton's Risk Triangle" hazard-risk methodology for obtaining a Heat-related Elderly Risk Index (HERI). The GAM procedure allowed for improved daytime and night-time LST estimations compared to the LRM approach. High-resolution maps of daytime and night-time HERI levels were developed for inland and coastal cities. Urban areas with the hazardous HERI level (very high risk) were not necessarily characterized by the highest temperatures. The hazardous HERI level was generally localized to encompass the city-centre in inland cities and the inner area in coastal cities. The two most dangerous HERI levels were greater in the coastal rather than inland cities. This study shows the great potential of combining geospatial technologies and spatial demographic characteristics within a simple and flexible framework in order to provide high-resolution urban mapping of daytime and night-time HERI. In this way, potential areas for intervention are immediately identified with up-to-street level details. This information could support public health operators and facilitate coordination for heat-related emergencies.

Urban-Hazard Risk Analysis: Mapping of Heat-Related Risks in the Elderly in Major Italian Cities

PubMed Central

Morabito, Marco; Crisci, Alfonso; Gioli, Beniamino; Gualtieri, Giovanni; Toscano, Piero; Di Stefano, Valentina; Orlandini, Simone; Gensini, Gian Franco

2015-01-01

Background Short-term impacts of high temperatures on the elderly are well known. Even though Italy has the highest proportion of elderly citizens in Europe, there is a lack of information on spatial heat-related elderly risks. Objectives Development of high-resolution, heat-related urban risk maps regarding the elderly population (≥65). Methods A long time-series (2001–2013) of remote sensing MODIS data, averaged over the summer period for eleven major Italian cities, were downscaled to obtain high spatial resolution (100 m) daytime and night-time land surface temperatures (LST). LST was estimated pixel-wise by applying two statistical model approaches: 1) the Linear Regression Model (LRM); 2) the Generalized Additive Model (GAM). Total and elderly population density data were extracted from the Joint Research Centre population grid (100 m) from the 2001 census (Eurostat source), and processed together using “Crichton’s Risk Triangle” hazard-risk methodology for obtaining a Heat-related Elderly Risk Index (HERI). Results The GAM procedure allowed for improved daytime and night-time LST estimations compared to the LRM approach. High-resolution maps of daytime and night-time HERI levels were developed for inland and coastal cities. Urban areas with the hazardous HERI level (very high risk) were not necessarily characterized by the highest temperatures. The hazardous HERI level was generally localized to encompass the city-centre in inland cities and the inner area in coastal cities. The two most dangerous HERI levels were greater in the coastal rather than inland cities. Conclusions This study shows the great potential of combining geospatial technologies and spatial demographic characteristics within a simple and flexible framework in order to provide high-resolution urban mapping of daytime and night-time HERI. In this way, potential areas for intervention are immediately identified with up-to-street level details. This information could support public health operators and facilitate coordination for heat-related emergencies. PMID:25985204

Islands in the sea: extreme female natal site fidelity in the Australian sea lion, Neophoca cinerea.

PubMed

Campbell, R A; Gales, N J; Lento, G M; Baker, C S

2008-02-23

Pinnipeds (seals, fur seals, sea lions and walrus) form large breeding aggregations with females often remaining faithful to a natal site or area. In these cases, females are philopatric to regional areas on broad geographical scales of hundreds to thousands of kilometers. An investigation of variation in a control region sequence of mtDNA in the Australian sea lion (Neophoca cinerea) has shown a case of extreme female natal site fidelity that has resulted in almost fixed population differentiation across its range (PhiST=0.93). This high level of population subdivision over short geographical distances (approx. 60 km) is unparalleled in any social marine mammal and reflects the unique life-history traits of this rare species. The high level of population subdivision and exclusive female natal site fidelity has important ramifications for conservation management, and poses many interesting questions of both academic and applied interest.

Shallow Population Genetic Structures of Thread-sail Filefish (Stephanolepis cirrhifer) Populations from Korean Coastal Waters.

PubMed

Yoon, M; Park, W; Nam, Y K; Kim, D S

2012-02-01

Genetic diversities, population genetic structures and demographic histories of the thread-sail filefish Stephanolepis cirrhifer were investigated by nucleotide sequencing of 336 base pairs of the mitochondrial DNA (mtDNA) control region in 111 individuals collected from six populations in Korean coastal waters. A total of 70 haplotypes were defined by 58 variable nucleotide sites. The neighbor-joining tree of the 70 haplotypes was shallow and did not provide evidence of geographical associations. Expansion of S. cirrhifer populations began approximate 51,000 to 102,000 years before present, correlating with the period of sea level rise since the late Pleistocene glacial maximum. High levels of haplotype diversities (0.974±0.029 to 1.000±0.076) and nucleotide diversities (0.014 to 0.019), and low levels of genetic differentiation among populations inferred from pairwise population F ST values (-0.007 to 0.107), support an expansion of the S. cirrhifer population. Hierarchical analysis of molecular variance (AMOVA) revealed weak but significant genetic structures among three groups (F CT = 0.028, p<0.05), and no genetic variation within groups (0.53%; F SC = 0.005, p = 0.23). These results may help establish appropriate fishery management strategies for stocks of S. cirrhifer and related species.

Shallow Population Genetic Structures of Thread-sail Filefish (Stephanolepis cirrhifer) Populations from Korean Coastal Waters

PubMed Central

Yoon, M.; Park, W.; Nam, Y. K.; Kim, D. S.

2012-01-01

Genetic diversities, population genetic structures and demographic histories of the thread-sail filefish Stephanolepis cirrhifer were investigated by nucleotide sequencing of 336 base pairs of the mitochondrial DNA (mtDNA) control region in 111 individuals collected from six populations in Korean coastal waters. A total of 70 haplotypes were defined by 58 variable nucleotide sites. The neighbor-joining tree of the 70 haplotypes was shallow and did not provide evidence of geographical associations. Expansion of S. cirrhifer populations began approximate 51,000 to 102,000 years before present, correlating with the period of sea level rise since the late Pleistocene glacial maximum. High levels of haplotype diversities (0.974±0.029 to 1.000±0.076) and nucleotide diversities (0.014 to 0.019), and low levels of genetic differentiation among populations inferred from pairwise population FST values (−0.007 to 0.107), support an expansion of the S. cirrhifer population. Hierarchical analysis of molecular variance (AMOVA) revealed weak but significant genetic structures among three groups (FCT = 0.028, p<0.05), and no genetic variation within groups (0.53%; FSC = 0.005, p = 0.23). These results may help establish appropriate fishery management strategies for stocks of S. cirrhifer and related species. PMID:25049547

Tracing back seed and pollen flow within the crop-wild Beta vulgaris complex: genetic distinctiveness vs. hot spots of hybridization over a regional scale.

PubMed

Viard, Frédérique; Arnaud, Jean-François; Delescluse, Maxime; Cuguen, Joël

2004-06-01

Hybrids between transgenic crops and wild relatives have been documented successfully in a wide range of cultivated species, having implications on conservation and biosafety management. Nonetheless, the magnitude and frequency of hybridization in the wild is still an open question, in particular when considering several populations at the landscape level. The Beta vulgaris complex provides an excellent biological model to tackle this issue. Weed beets contaminating sugar beet fields are expected to act as a relay between wild populations and crops and from crops-to-crops. In one major European sugar beet production area, nine wild populations and 12 weed populations were genetically characterized using cytoplasmic markers specific to the cultivated lines and nuclear microsatellite loci. A tremendous overall genetic differentiation between neighbouring wild and weed populations was depicted. However, genetic admixture analyses at the individual level revealed clear evidence for gene flow between wild and weed populations. In particular, one wild population displayed a high magnitude of nuclear genetic admixture, reinforced by direct seed flow as evidenced by cytoplasmic markers. Altogether, weed beets were shown to act as relay for gene flow between crops to wild populations and crops to crops by pollen and seeds at a landscape level.

RAINIER: A simulation tool for distributions of excited nuclear states and cascade fluctuations

NASA Astrophysics Data System (ADS)

Kirsch, L. E.; Bernstein, L. A.

2018-06-01

A new code has been developed named RAINIER that simulates the γ-ray decay of discrete and quasi-continuum nuclear levels for a user-specified range of energy, angular momentum, and parity including a realistic treatment of level spacing and transition width fluctuations. A similar program, DICEBOX, uses the Monte Carlo method to simulate level and width fluctuations but is restricted in its initial level population algorithm. On the other hand, modern reaction codes such as TALYS and EMPIRE populate a wide range of states in the residual nucleus prior to γ-ray decay, but do not go beyond the use of deterministic functions and therefore neglect cascade fluctuations. This combination of capabilities allows RAINIER to be used to determine quasi-continuum properties through comparison with experimental data. Several examples are given that demonstrate how cascade fluctuations influence experimental high-resolution γ-ray spectra from reactions that populate a wide range of initial states.

Genetic Diversity and Population Structure of Ethiopian Sheep Populations Revealed by High-Density SNP Markers

PubMed Central

Edea, Zewdu; Dessie, Tadelle; Dadi, Hailu; Do, Kyoung-Tag; Kim, Kwan-Suk

2017-01-01

Sheep in Ethiopia are adapted to a wide range of environments, including extreme habitats. Elucidating their genetic diversity is critical for improving breeding strategies and mapping quantitative trait loci associated with productivity. To this end, the present study investigated the genetic diversity and population structure of five Ethiopian sheep populations exhibiting distinct phenotypes and sampled from distinct production environments, including arid lowlands and highlands. To investigate the genetic relationships in greater detail and infer population structure of Ethiopian sheep breeds at the continental and global levels, we analyzed genotypic data of selected sheep breeds from the Ovine SNP50K HapMap dataset. All Ethiopian sheep samples were genotyped with Ovine Infinium HD SNP BeadChip (600K). Mean genetic diversity ranged from 0.29 in Arsi-Bale to 0.32 in Menz sheep, while estimates of genetic differentiation among populations ranged from 0.02 to 0.07, indicating low to moderate differentiation. An analysis of molecular variance revealed that 94.62 and 5.38% of the genetic variation was attributable to differences within and among populations, respectively. Our population structure analysis revealed clustering of five Ethiopian sheep populations according to tail phenotype and geographic origin—i.e., short fat-tailed (very cool high-altitude), long fat-tailed (mid to high-altitude), and fat-rumped (arid low-altitude), with clear evidence of admixture between long fat-tailed populations. North African sheep breeds showed higher levels of within-breed diversity, but were less differentiated than breeds from Eastern and Southern Africa. When African breeds were grouped according to geographic origin (North, South, and East), statistically significant differences were detected among groups (regions). A comparison of population structure between Ethiopian and global sheep breeds showed that fat-tailed breeds from Eastern and Southern Africa clustered together, suggesting that these breeds were introduced to the African continent via the Horn and migrated further south. PMID:29312441

Population and genomic lessons from genetic analysis of two Indian populations.

PubMed

Juyal, Garima; Mondal, Mayukh; Luisi, Pierre; Laayouni, Hafid; Sood, Ajit; Midha, Vandana; Heutink, Peter; Bertranpetit, Jaume; Thelma, B K; Casals, Ferran

2014-10-01

Indian demographic history includes special features such as founder effects, interpopulation segregation, complex social structure with a caste system and elevated frequency of consanguineous marriages. It also presents a higher frequency for some rare mendelian disorders and in the last two decades increased prevalence of some complex disorders. Despite the fact that India represents about one-sixth of the human population, deep genetic studies from this terrain have been scarce. In this study, we analyzed high-density genotyping and whole-exome sequencing data of a North and a South Indian population. Indian populations show higher differentiation levels than those reported between populations of other continents. In this work, we have analyzed its consequences, by specifically assessing the transferability of genetic markers from or to Indian populations. We show that there is limited genetic marker portability from available genetic resources such as HapMap or the 1,000 Genomes Project to Indian populations, which also present an excess of private rare variants. Conversely, tagSNPs show a high level of portability between the two Indian populations, in contrast to the common belief that North and South Indian populations are genetically very different. By estimating kinship from mates and consanguinity in our data from trios, we also describe different patterns of assortative mating and inbreeding in the two populations, in agreement with distinct mating preferences and social structures. In addition, this analysis has allowed us to describe genomic regions under recent adaptive selection, indicating differential adaptive histories for North and South Indian populations. Our findings highlight the importance of considering demography for design and analysis of genetic studies, as well as the need for extending human genetic variation catalogs to new populations and particularly to those with particular demographic histories.

Association between carotid intima-media thickness and fasting blood glucose level: A population-based cross-sectional study among low-income adults in rural China.

PubMed

Gao, Liu; Bai, Lingling; Shi, Min; Ni, Jingxian; Lu, Hongyan; Wu, Yanan; Tu, Jun; Ning, Xianjia; Wang, Jinghua; Li, Yukun

2017-11-01

Carotid intima-media thickness (CIMT) is an established predictor of cardiovascular disease and stroke. We aimed to identify the association between CIMT and blood glucose, as well as the risk factors associated with increased CIMT in a low-income Chinese population. Stroke-free and cardiovascular disease-free residents aged ≥45 years were recruited. B-mode ultrasonography was carried out to measure CIMT. There were 2,643 participants (71.0%) in the normal group, 549 (14.7%) in the impaired fasting glucose group and 533 (14.3%) in the diabetes mellitus group. The determinants of increased CIMT were older age; male sex; low education; hypertension; smoking; high levels of systolic blood pressure, fasting blood glucose and low-density lipoprotein cholesterol; and low levels of diastolic blood pressure, triglycerides and high-density lipoprotein cholesterol, after adjusting for covariates. Age and hypertension were the common risk factors for increased CIMT in all three groups. Furthermore, male sex, smoking and high low-density lipoprotein cholesterol level were positively associated with the mean CIMT in the normal group; high triglycerides levels were negatively associated with the mean CIMT in the impaired fasting glucose group; and alcohol consumption was an independent risk factor for mean CIMT in the diabetes mellitus group. Hypertension was the greatest risk factor for increased CIMT. These findings suggest that it is crucial to manage and control traditional risk factors in low-income populations in China in order to decelerate the recent dramatic increase in stroke incidence, and to reduce the burden of stroke. © 2017 The Authors. Journal of Diabetes Investigation published by Asian Association for the Study of Diabetes (AASD) and John Wiley & Sons Australia, Ltd.

Genetic structure of pike (Esox lucius) reveals a complex and previously unrecognized colonization history of Ireland

PubMed Central

Pedreschi, Debbi; Kelly-Quinn, Mary; Caffrey, Joe; O’Grady, Martin; Mariani, Stefano; Phillimore, Albert

2014-01-01

Aim We investigated genetic variation of Irish pike populations and their relationship with European outgroups, in order to elucidate the origin of this species to the island, which is largely assumed to have occurred as a human-mediated introduction over the past few hundred years. We aimed thereby to provide new insights into population structure to improve fisheries and biodiversity management in Irish freshwaters. Location Ireland, Britain and continental Europe. Methods A total of 752 pike (Esox lucius) were sampled from 15 locations around Ireland, and 9 continental European sites, and genotyped at six polymorphic microsatellite loci. Patterns and mechanisms of population genetic structure were assessed through a diverse array of methods, including Bayesian clustering, hierarchical analysis of molecular variance, and approximate Bayesian computation. Results Varying levels of genetic diversity and a high degree of population genetic differentiation were detected. Clear substructure within Ireland was identified, with two main groups being evident. One of the Irish populations showed high similarity with British populations. The other, more widespread, Irish strain did not group with any European population examined. Approximate Bayesian computation suggested that this widespread Irish strain is older, and may have colonized Ireland independently of humans. Main conclusions Population genetic substructure in Irish pike is high and comparable to the levels observed elsewhere in Europe. A comparison of evolutionary scenarios upholds the possibility that pike may have colonized Ireland in two ‘waves’, the first of which, being independent of human colonization, would represent the first evidence for natural colonization of a non-anadromous freshwater fish to the island of Ireland. Although further investigations using comprehensive genomic techniques will be necessary to confirm this, the present results warrant a reappraisal of current management strategies for this species. PMID:25435649

Genetic structure of pike (Esox lucius) reveals a complex and previously unrecognized colonization history of Ireland.

PubMed

Pedreschi, Debbi; Kelly-Quinn, Mary; Caffrey, Joe; O'Grady, Martin; Mariani, Stefano; Phillimore, Albert

2014-03-01

We investigated genetic variation of Irish pike populations and their relationship with European outgroups, in order to elucidate the origin of this species to the island, which is largely assumed to have occurred as a human-mediated introduction over the past few hundred years. We aimed thereby to provide new insights into population structure to improve fisheries and biodiversity management in Irish freshwaters. Ireland, Britain and continental Europe. A total of 752 pike ( Esox lucius ) were sampled from 15 locations around Ireland, and 9 continental European sites, and genotyped at six polymorphic microsatellite loci. Patterns and mechanisms of population genetic structure were assessed through a diverse array of methods, including Bayesian clustering, hierarchical analysis of molecular variance, and approximate Bayesian computation. Varying levels of genetic diversity and a high degree of population genetic differentiation were detected. Clear substructure within Ireland was identified, with two main groups being evident. One of the Irish populations showed high similarity with British populations. The other, more widespread, Irish strain did not group with any European population examined. Approximate Bayesian computation suggested that this widespread Irish strain is older, and may have colonized Ireland independently of humans. Population genetic substructure in Irish pike is high and comparable to the levels observed elsewhere in Europe. A comparison of evolutionary scenarios upholds the possibility that pike may have colonized Ireland in two 'waves', the first of which, being independent of human colonization, would represent the first evidence for natural colonization of a non-anadromous freshwater fish to the island of Ireland. Although further investigations using comprehensive genomic techniques will be necessary to confirm this, the present results warrant a reappraisal of current management strategies for this species.

Population Structure, Genetic Diversity and Molecular Marker-Trait Association Analysis for High Temperature Stress Tolerance in Rice

PubMed Central

Barik, Saumya Ranjan; Sahoo, Ambika; Mohapatra, Sudipti; Nayak, Deepak Kumar; Mahender, Anumalla; Meher, Jitandriya; Anandan, Annamalai

2016-01-01

Rice exhibits enormous genetic diversity, population structure and molecular marker-traits associated with abiotic stress tolerance to high temperature stress. A set of breeding lines and landraces representing 240 germplasm lines were studied. Based on spikelet fertility percent under high temperature, tolerant genotypes were broadly classified into four classes. Genetic diversity indicated a moderate level of genetic base of the population for the trait studied. Wright’s F statistic estimates showed a deviation of Hardy-Weinberg expectation in the population. The analysis of molecular variance revealed 25 percent variation between population, 61 percent among individuals and 14 percent within individuals in the set. The STRUCTURE analysis categorized the entire population into three sub-populations and suggested that most of the landraces in each sub-population had a common primary ancestor with few admix individuals. The composition of materials in the panel showed the presence of many QTLs representing the entire genome for the expression of tolerance. The strongly associated marker RM547 tagged with spikelet fertility under stress and the markers like RM228, RM205, RM247, RM242, INDEL3 and RM314 indirectly controlling the high temperature stress tolerance were detected through both mixed linear model and general linear model TASSEL analysis. These markers can be deployed as a resource for marker-assisted breeding program of high temperature stress tolerance. PMID:27494320

Population Structure, Genetic Diversity and Molecular Marker-Trait Association Analysis for High Temperature Stress Tolerance in Rice.

PubMed

Pradhan, Sharat Kumar; Barik, Saumya Ranjan; Sahoo, Ambika; Mohapatra, Sudipti; Nayak, Deepak Kumar; Mahender, Anumalla; Meher, Jitandriya; Anandan, Annamalai; Pandit, Elssa

2016-01-01

Rice exhibits enormous genetic diversity, population structure and molecular marker-traits associated with abiotic stress tolerance to high temperature stress. A set of breeding lines and landraces representing 240 germplasm lines were studied. Based on spikelet fertility percent under high temperature, tolerant genotypes were broadly classified into four classes. Genetic diversity indicated a moderate level of genetic base of the population for the trait studied. Wright's F statistic estimates showed a deviation of Hardy-Weinberg expectation in the population. The analysis of molecular variance revealed 25 percent variation between population, 61 percent among individuals and 14 percent within individuals in the set. The STRUCTURE analysis categorized the entire population into three sub-populations and suggested that most of the landraces in each sub-population had a common primary ancestor with few admix individuals. The composition of materials in the panel showed the presence of many QTLs representing the entire genome for the expression of tolerance. The strongly associated marker RM547 tagged with spikelet fertility under stress and the markers like RM228, RM205, RM247, RM242, INDEL3 and RM314 indirectly controlling the high temperature stress tolerance were detected through both mixed linear model and general linear model TASSEL analysis. These markers can be deployed as a resource for marker-assisted breeding program of high temperature stress tolerance.

[The affect of mass tourism on the population of the Balearic Islands during the last 40 years (1950-1989)].

PubMed

Salva I Tomas, P A

1991-01-01

The impact of tourism on population trends in Spain's Balearic Islands since 1950 is analyzed. The author notes that tourism generated high levels of in-migration and an increase in fertility until about 1975. Subsequently, the birth rate has declined, population growth has slowed down, and the population has grown older. There is still a noticeable contrast between the demography of coastal areas and inland agrarian regions. (SUMMARY IN ENG AND SPA)

Patterns of gene variation in central and marginal populations of Drosophila robusta.

PubMed

Prakash, S

1973-10-01

The central and marginal populations of D. robusta differ greatly in the level of inversion polymorphism; the marginal populations are monomorphic or nearly so and the central populations are highly polymorphic. This paper presents the frequencies of alleles at forty gene loci in various populations of D. robusta, studied by electrophoresis of proteins and enzymes. Population samples were obtained from eight widely separated populations of D. robusta which included the central, the extreme marginal and the intervening populations between the center and the margins. We find that the proportion of polymorphic loci and average heterozygosity per individual is slightly higher in the marginal populations than the central populations. In D. robusta on an average, 39% of the loci are polymorphic and the average proportion of loci heterozygous per individual is 11%. A breakdown of loci in three categories, viz, hydrolytic enzymes and some other enzymes, larval proteins and glycolytic and Kreb's cycle enzymes, shows that in all populations the level of polymorphism is highest in the hydrolytic enzymes, intermediate in larval proteins and least in the glycolytic and Kreb's cycle enzymes. On the average, the proportion of loci heterozygous per individual for three groups of loci is: hydrolytic enzymes and others (.164), larval proteins (.115) and glycolytic and Kreb's cycle enzymes (.037). We also observe that in all populations the level of polymorphism on the X chromosome is far less than the expected 38%; in salivary gland cells the euchromatic length of the X chromosome is 38% of the entire genome. Lower levels of polymorphism for the X chromosome loci are explained due to low probability of balanced polymorphisms for the X-linked loci since the conditions for establishment of balanced polymorphism for X-linked loci are more restrictive than for the autosomal loci.-The polymorphic loci can be grouped according to pattern of allele frequencies in different populations as follows: (1) The allele frequencies are similar in all populations at the XDH, Pep-1 and Hex-1 loci. (2) The alleles at the Est-1, Est-2, Amy loci and the AP-4(1.0) and the LAP-1(.90) alleles show north south clinal change in frequency. (3) There is north south and east west differentiation at the Pt-5, Pt-8 and Pt-9 loci and the allele AP-4(.81). (4) Polymorphism at loci such as Fum, B.Ox, Hex-8, Pep-2 and Pep-3 are restricted to only one or two of the populations. (5) Allele frequencies at the MDH and ODH loci fluctuate between populations. (6) Allele frequencies at many polymorphic loci such as Est-1, Est-2, LAP-1, AP-4, Pt-5, Pt-8, Pt-9, Pt-16, MDH, Fum change clinally within a gene arrangement. The pattern of gene variation in D. robusta is very complex and cannot be easily explained due to migration of neutral alleles between once-isolated populations or to semi-isolation of neutral alleles. The observations of the pattern of allele variation in different populations, high levels of polymorphism in the marginal populations which have small population size and low levels of polymorphism of the X chromosome loci all support the argument in favor of balancing selection as the main mechanism for the maintenance of these polymorphisms. Environmental factors must play a role in the maintenance of a great deal of these polymorphisms, since we observe clinal allele frequency changes even within a given inversion type.

Patterns of Gene Variation in Central and Marginal Populations of DROSOPHILA ROBUSTA

PubMed Central

Prakash, Satya

1973-01-01

The central and marginal populations of D. robusta differ greatly in the level of inversion polymorphism; the marginal populations are monomorphic or nearly so and the central populations are highly polymorphic. This paper presents the frequencies of alleles at forty gene loci in various populations of D. robusta, studied by electrophoresis of proteins and enzymes. Population samples were obtained from eight widely separated populations of D. robusta which included the central, the extreme marginal and the intervening populations between the center and the margins. We find that the proportion of polymorphic loci and average heterozygosity per individual is slightly higher in the marginal populations than the central populations. In D. robusta on an average, 39% of the loci are polymorphic and the average proportion of loci heterozygous per individual is 11%. A breakdown of loci in three categories, viz, hydrolytic enzymes and some other enzymes, larval proteins and glycolytic and Kreb's cycle enzymes, shows that in all populations the level of polymorphism is highest in the hydrolytic enzymes, intermediate in larval proteins and least in the glycolytic and Kreb's cycle enzymes. On the average, the proportion of loci heterozygous per individual for three groups of loci is: hydrolytic enzymes and others (.164), larval proteins (.115) and glycolytic and Kreb's cycle enzymes (.037). We also observe that in all populations the level of polymorphism on the X chromosome is far less than the expected 38%; in salivary gland cells the euchromatic length of the X chromosome is 38% of the entire genome. Lower levels of polymorphism for the X chromosome loci are explained due to low probability of balanced polymorphisms for the X-linked loci since the conditions for establishment of balanced polymorphism for X-linked loci are more restrictive than for the autosomal loci.—The polymorphic loci can be grouped according to pattern of allele frequencies in different populations as follows: (1) The allele frequencies are similar in all populations at the XDH, Pep-1 and Hex-1 loci. (2) The alleles at the Est-1, Est-2, Amy loci and the AP-41.0 and the LAP-1.90 alleles show north south clinal change in frequency. (3) There is north south and east west differentiation at the Pt-5, Pt-8 and Pt-9 loci and the allele AP-4.81. (4) Polymorphism at loci such as Fum, B.Ox, Hex-8, Pep-2 and Pep-3 are restricted to only one or two of the populations. (5) Allele frequencies at the MDH and ODH loci fluctuate between populations. (6) Allele frequencies at many polymorphic loci such as Est-1, Est-2, LAP-1, AP-4, Pt-5, Pt-8, Pt-9, Pt-16, MDH, Fum change clinally within a gene arrangement. The pattern of gene variation in D. robusta is very complex and cannot be easily explained due to migration of neutral alleles between once-isolated populations or to semi-isolation of neutral alleles. The observations of the pattern of allele variation in different populations, high levels of polymorphism in the marginal populations which have small population size and low levels of polymorphism of the X chromosome loci all support the argument in favor of balancing selection as the main mechanism for the maintenance of these polymorphisms. Environmental factors must play a role in the maintenance of a great deal of these polymorphisms, since we observe clinal allele frequency changes even within a given inversion type. PMID:4203580

Methodological assessment of 2b-RAD genotyping technique for population structure inferences in yellowfin tuna (Thunnus albacares).

PubMed

Pecoraro, Carlo; Babbucci, Massimiliano; Villamor, Adriana; Franch, Rafaella; Papetti, Chiara; Leroy, Bruno; Ortega-Garcia, Sofia; Muir, Jeff; Rooker, Jay; Arocha, Freddy; Murua, Hilario; Zudaire, Iker; Chassot, Emmanuel; Bodin, Nathalie; Tinti, Fausto; Bargelloni, Luca; Cariani, Alessia

2016-02-01

Global population genetic structure of yellowfin tuna (Thunnus albacares) is still poorly understood despite its relevance for the tuna fishery industry. Low levels of genetic differentiation among oceans speak in favour of the existence of a single panmictic population worldwide of this highly migratory fish. However, recent studies indicated genetic structuring at a much smaller geographic scales than previously considered, pointing out that YFT population genetic structure has not been properly assessed so far. In this study, we demonstrated for the first time, the utility of 2b-RAD genotyping technique for investigating population genetic diversity and differentiation in high gene-flow species. Running de novo pipeline in Stacks, a total of 6772 high-quality genome-wide SNPs were identified across Atlantic, Indian and Pacific population samples representing all major distribution areas. Preliminary analyses showed shallow but significant population structure among oceans (FST=0.0273; P-value<0.01). Discriminant Analysis of Principal Components endorsed the presence of genetically discrete yellowfin tuna populations among three oceanic pools. Although such evidence needs to be corroborated by increasing sample size, these results showed the efficiency of this genotyping technique in assessing genetic divergence in a marine fish with high dispersal potential. Copyright © 2015 Elsevier B.V. All rights reserved.

Agents affecting health of mother and child in a rural area of Kenya. XVIII. Fertility, mortality and migration in 1975-1978.

PubMed

Van Ginneken, J K; Voorhoeve, A M; Omondi-Odhiambo; Muller, A S; Blok, P G; W'Oigo, H O

1980-06-01

The results reported here are based on age-specific rates and are, therefore, more sensitive and meaningful as indicators of fertility and mortality than the crude rates mentioned in the previous article. The results confirm that, compared to world standards, the study area is characterized by a high level of fertility and a fairly low level of mortality. Fertility and mortality are, however, lower in the study area in comparison to Kenya as a whole. Another characteristic is high population mobility which is of two types: temporary migration of absent members of the population, and permanent in- and out-migration.

Graduate-entry medical students: older and wiser but not less distressed.

PubMed

Casey, Dion; Thomas, Susan; Hocking, Darren R; Kemp-Casey, Anna

2016-02-01

Australia has a growing number of graduate-entry medical courses. It is known that undergraduate medical students have high levels of psychological distress; however, little is known about graduate-entry medical students. We examined whether graduate-entry medical students had higher levels of psychological distress than the same-age general population. Psychological distress was assessed in 122 graduate-entry medical students in an Australian graduate-entry medical school using the 21-item Depression Anxiety and Stress Scale. Mean scores and the proportion of students with scores in the highly distressed range were compared with non-clinical population norms. Scores were also compared across demographic characteristics. Medical students reported higher mean depression, anxiety and stress scores than the general population and were more likely to score in the moderate to extremely high range for anxiety (45% vs. 13%; p<0.001) and stress (17% vs. 13%; p=0.003). Anxiety and stress were higher in students aged ≥30 years than in younger students. Despite their maturity, graduate-entry students experienced high psychological distress. Anxiety and stress were higher, not lower, with increasing age. Our results suggest that graduate-entry medical students warrant the same level of concern as their school-leaving counterparts. Further interventions to support these students during medical school are warranted. © The Royal Australian and New Zealand College of Psychiatrists 2015.

[Simulating measles and rubella elimination levels according to social stratification and interaction].

PubMed

Hincapié-Palacio, Doracelly; Ospina-Giraldo, Juan; Gómez-Arias, Rubén D; Uyi-Afuwape, Anthony; Chowell-Puente, Gerardo

2010-02-01

The study was aimed at comparing measles and rubella disease elimination levels in a homogeneous and heterogeneous population according to socioeconomic status with interactions amongst low- and high-income individuals and diversity in the average number of contacts amongst them. Effective reproductive rate simulations were deduced from a susceptibleinfected- recovered (SIR) mathematical model according to different immunisation rates using measles (1980 and 2005) and rubella (1998 and 2005) incidence data from Latin-America and the Caribbean. Low- and high-income individuals' social interaction and their average number of contacts were analysed by bipartite random network analysis. MAPLE 12 (Maplesoft Inc, Ontario Canada) software was used for making the simulations. The progress made in eliminating both diseases between both periods of time was reproduced in the socially-homogeneous population. Measles (2005) would be eliminated in high- and low-income groups; however, it would only be achieved in rubella (2005) if there were a high immunity rate amongst the low-income group. If the average number of contacts were varied, then rubella would not be eliminated, even with a 95 % immunity rate. Monitoring the elimination level in diseases like measles and rubella requires that socio-economic status be considered as well as the population's interaction pattern. Special attention should be paid to communities having diversity in their average number of contacts occurring in confined spaces such as displaced communities, prisons, educational establishments, or hospitals.

Africa: continent of genome contrasts with implications for biomedical research and health.

PubMed

Ramsay, Michèle

2012-08-31

The genomic architecture of African populations is poorly understood and there is considerable variation between ethno-linguistic groups. Genome-wide approaches have been extensively applied to search for genetic associations to complex traits in Europeans, but rarely in Africans. This is largely attributed to lower levels of funding, poor infrastructure and public health systems, and to the small pool of trained scientists. High levels of genetic variation and underlying population structure in Africans present significant challenges, but lower levels of linkage disequilibrium provide an opportunity for more effective localisation of causal variants. High throughput technologies, including dense genotyping arrays, genome sequencing and epigenome studies, together with plummeting costs, are making research more affordable, even for African scientists. Understanding the interactions between genome structure and environmental influences is essential to interpreting their contributions to the increase in infectious diseases and non-communicable diseases, exacerbated by adverse environments and lifestyle choices. The unique genome dynamics in African populations have an important role to play in understanding human health and susceptibility to disease. Copyright © 2012. Published by Elsevier B.V.

Functional role of long-lived flowers in preventing pollen limitation in a high elevation outcrossing species

PubMed Central

Pacheco, Diego Andrés; Dudley, Leah S

2017-01-01

Abstract Low pollinator visitation in harsh environments may lead to pollen limitation which can threaten population persistence. Consequently, avoidance of pollen limitation is expected in outcrossing species subjected to habitually low pollinator service. The elevational decline in visitation rates on many high mountains provides an outstanding opportunity for addressing this question. According to a recent meta-analysis, levels of pollen limitation in alpine and lowland species do not differ. If parallel trends are manifested among populations of alpine species with wide elevational ranges, how do their uppermost populations contend with lower visitation? We investigated visitation rates and pollen limitation in high Andean Rhodolirium montanum. We test the hypothesis that lower visitation rates at high elevations are compensated for by the possession of long-lived flowers. Visitation rates decreased markedly over elevation as temperature decreased. Pollen limitation was absent at the low elevation site but did occur at the high elevation site. While initiation of stigmatic pollen deposition at high elevations was not delayed, rates of pollen arrival were lower, and cessation of pollination, as reflected by realized flower longevity, occurred later in the flower lifespan. Comparison of the elevational visitation decline and levels of pollen limitation indicates that flower longevity partially compensates for the lower visitation rates at high elevation. The functional role of flower longevity, however, was strongly masked by qualitative pollen limitation arising from higher abortion levels attributable to transference of genetically low-quality pollen in large clones. Stronger clonal growth at high elevations could counterbalance the negative fitness consequences of residual pollen limitation due to low visitation rates and/or difficult establishment under colder conditions. Visitation rates on the lower part of the elevational range greatly exceeded community rates recorded several decades ago when the planet was cooler. Current pollen limitation for some species in some habitats might underestimate historical levels. PMID:29225762

Studies of discharge mechanisms in high pressure gases-applications to high efficiency high power lasers. Ph.D. Thesis. Semiannual Progress Report

NASA Technical Reports Server (NTRS)

Cherrington, B. E.; Verdeyen, J. T.; Eden, J. G.; Leslie, S. G.

1975-01-01

By measuring the absorption and emission cantinua of various states in the cesium/xenon molecule, the collisional rates critical in populating the alkali/rare gas excimer levels have been estimated. Cs atomic states that are weakly optically connected to ground have been shown to form excimer levels that are attractive as potential dissociation lasers. In particular, the (Cs/7 2S/Xe) excited molecule appears promising as a source of high energy laser radiation due to its large dissociation energy, stimulated emission cross section, and small population inversion densities. Monitoring of the optically pumped Cs2 molecular absorption profile in the presence of xenon shows a drastic change with increasing xenon pressure for the Cs2C band. Dominant absorption at large xenon densities is centered around approximately 6380 A as opposed to 6300 A for lower perturber pressure.

Population structure and comparative phylogeography of jack species (Caranx ignobilis and C. melampygus) in the high Hawaiian Islands.

PubMed

Santos, Scott R; Xiang, Yu; Tagawa, Annette W

2011-01-01

Members of the family Carangidae are top-level predators and highly prized food and sport fishes. Although ecologically and economically important, little is known about the biology of numerous species in the family. This is particularly true of the jacks Caranx ignobilis and C. melampygus, which have experienced recent population reductions around the high Hawaiian Islands due to overfishing. Previous studies have documented territorial tendencies as well as cases of long-distance excursions in both species, suggesting populations may exhibit a range of structure at the genetic level. To explore this possibility, mitochondrial DNA ATPase6 and ATPase8 gene sequence variation was assessed from 91 individuals (33 C. ignobilis and 58 C. melampygus) spanning the islands of Kaua'i, O'ahu, Moloka'i, Maui, and Hawai'i. Although a total of 20 distinct haplotypes (8 for C. ignobilis; 12 for C. melampygus) were recovered, no evidence of population structure was found for either species across the examined geographic range. However, distinct demographic patterns were identified, implying differing evolutionary histories and/or population dynamics. Additionally, ∼ 6% of the examined C. ignobilis were C. ignobilis × C. melampygus hybrids because they harbored mitochondrial haplotypes typical of C. melampygus. These hybrids contribute to measurable gene flow between the species and may play a significant role in the evolution of the genus.

Differential expression of vacuolar and defective cell wall invertase genes in roots and seeds of metalliferous and non-metalliferous populations of Rumex dentatus under copper stress.

PubMed

Xu, Zhong-Rui; Cai, Shen-Wen; Huang, Wu-Xing; Liu, Rong-Xiang; Xiong, Zhi-Ting

2018-01-01

Acid invertase activities in roots and young seeds of a metalliferous population (MP) of Rumex dentatus were previously observed to be significantly higher than those of a non-metalliferous population (NMP) under Cu stress. To date, no acid invertase gene has been cloned from R. dentatus. Here, we isolated four full-length cDNAs from the two populations of R. dentatus, presumably encoding cell wall (RdnCIN1 and RdmCIN1 from the NMP and MP, respectively) and vacuolar invertases (RdnVIN1 and RdmVIN1 from the NMP and MP, respectively). Unexpectedly, RdnCIN1 and RdmCIN1 most likely encode special defective invertases with highly attenuated sucrose-hydrolyzing capacity. The transcript levels of RdmCIN1 were significantly higher than those of RdnCIN1 in roots and young seeds under Cu stress, whereas under control conditions, the former was initially lower than the latter. Unexpected high correlations were observed between the transcript levels of RdnCIN1 and RdmCIN1 and the activity of cell wall invertase, even though RdnCIN1 and RdmCIN1 do not encode catalytically active invertases. Similarly, the transcript levels of RdmVIN1 in roots and young seeds were increased under Cu stress, whereas those of RdnVIN1 were decreased. The high correlations between the transcript levels of RdnVIN1 and RdmVIN1 and the activity of vacuolar invertase indicate that RdnVIN1 and RdmVIN1 might control distinct vacuolar invertase activities in the two populations. Moreover, a possible indirect role for acid invertases in Cu tolerance, mediated by generating a range of sugars used as nutrients and signaling molecules, is discussed. Copyright © 2017 Elsevier Inc. All rights reserved.

Multilevel Spatial Structure Impacts on the Pollination Services of Comarum palustre (Rosaceae)

PubMed Central

Somme, Laurent; Mayer, Carolin; Jacquemart, Anne-Laure

2014-01-01

Habitat destruction and fragmentation accelerate pollinator decline, consequently disrupting ecosystem processes such as pollination. To date, the impacts of multilevel spatial structure on pollination services have rarely been addressed. We focused on the effects of population spatial structure on the pollination services of Comarum palustre at three levels (i.e. within-population, between-populations and landscape). For three years, we investigated 14 Belgian populations, which differed in their within-population flower density, population surface, closure (i.e. proportion of the population edge that consisted of woody elements) and isolation (i.e. percentage of woody area cover within a 500 m radius from the population centre). We tested whether these spatial characteristics impact on pollinator abundance and visitation rate and thus, reproductive success of C. palustre. Insects were observed in 15 randomly-chosen plots in each population. We tested for pollen limitation with supplemental hand-cross pollination. Bumble bees and solitary bees were the major pollinators through all populations. Within populations, plots with high flower densities attracted high numbers of bumble bees and other insects. High bumble bee and solitary bee abundance was observed in populations presenting high proportions of woody edges and in populations within landscapes presenting high proportions of woody areas. Seed set resulting from open pollination varied with bumble bee and solitary bee visitation rate, leading to increased pollen limitation when pollinators were scarce. Since the reproductive success depended on the visitation rate of the main pollinators, which depended on multilevel spatial structure, wetland management plans should pay special attention to favour a mosaic of biotopes, including nesting sites and food resources for insects. This study particularly supports the relevance of a mix wetlands and woody habitats to bees. PMID:24915450

Multilevel spatial structure impacts on the pollination services of Comarum palustre (Rosaceae).

PubMed

Somme, Laurent; Mayer, Carolin; Jacquemart, Anne-Laure

2014-01-01

Habitat destruction and fragmentation accelerate pollinator decline, consequently disrupting ecosystem processes such as pollination. To date, the impacts of multilevel spatial structure on pollination services have rarely been addressed. We focused on the effects of population spatial structure on the pollination services of Comarum palustre at three levels (i.e. within-population, between-populations and landscape). For three years, we investigated 14 Belgian populations, which differed in their within-population flower density, population surface, closure (i.e. proportion of the population edge that consisted of woody elements) and isolation (i.e. percentage of woody area cover within a 500 m radius from the population centre). We tested whether these spatial characteristics impact on pollinator abundance and visitation rate and thus, reproductive success of C. palustre. Insects were observed in 15 randomly-chosen plots in each population. We tested for pollen limitation with supplemental hand-cross pollination. Bumble bees and solitary bees were the major pollinators through all populations. Within populations, plots with high flower densities attracted high numbers of bumble bees and other insects. High bumble bee and solitary bee abundance was observed in populations presenting high proportions of woody edges and in populations within landscapes presenting high proportions of woody areas. Seed set resulting from open pollination varied with bumble bee and solitary bee visitation rate, leading to increased pollen limitation when pollinators were scarce. Since the reproductive success depended on the visitation rate of the main pollinators, which depended on multilevel spatial structure, wetland management plans should pay special attention to favour a mosaic of biotopes, including nesting sites and food resources for insects. This study particularly supports the relevance of a mix wetlands and woody habitats to bees.

Alteration of serum thymus and activation-regulated chemokine level during biologic therapy for psoriasis: Possibility as a marker reflecting favorable response to anti-interleukin-17A agents.

PubMed

Shibuya, Takashi; Honma, Masaru; Iinuma, Shin; Iwasaki, Takeshi; Takahashi, Hidetoshi; Ishida-Yamamoto, Akemi

2018-06-01

Biologics show great efficacy in treating psoriasis, a chronic inflammatory skin disease. The high cost and side-effects of biologics, dose-reduction, elongation of administration interval and suspension are possible options. However, there has been no reliable biomarker we can use when we consider these moderations in therapy. This study was conducted to test the possibility of using serum thymus and activation-regulated chemokine (TARC) level as an indicator for step down of biologic therapy. Serum TARC level was measured in 70 psoriatic patients at Asahikawa Medical University, and a correlation of TARC and severity of skin lesions was analyzed. Referring to serum TARC level, psoriatic patients can be divided into two groups. One is a population in which serum TARC level is positively correlated with severity of skin lesions, and the other is a population with low psoriatic severity and high TARC level. Serum TARC level was higher in the group that achieved PASI-clear with biologics than in the group which did not achieve PASI-clear. Among biologics, the group treated with secukinumab, an anti-interleukin (IL)-17A agent, showed significantly higher TARC level compared with the group treated with anti-tumor necrosis factor agents. In certain populations achieving PASI-clear, serum TARC level may be a potent marker reflecting better response to IL-17A inhibitors, and in this case step down of treatment for psoriasis is possible. © 2018 Japanese Dermatological Association.

Mitochondrial DNA Markers Reveal High Genetic Diversity but Low Genetic Differentiation in the Black Fly Simulium tani Takaoka & Davies along an Elevational Gradient in Malaysia

PubMed Central

Low, Van Lun; Adler, Peter H.; Takaoka, Hiroyuki; Ya’cob, Zubaidah; Lim, Phaik Eem; Tan, Tiong Kai; Lim, Yvonne A. L.; Chen, Chee Dhang; Norma-Rashid, Yusoff; Sofian-Azirun, Mohd

2014-01-01

The population genetic structure of Simulium tani was inferred from mitochondria-encoded sequences of cytochrome c oxidase subunits I (COI) and II (COII) along an elevational gradient in Cameron Highlands, Malaysia. A statistical parsimony network of 71 individuals revealed 71 haplotypes in the COI gene and 43 haplotypes in the COII gene; the concatenated sequences of the COI and COII genes revealed 71 haplotypes. High levels of genetic diversity but low levels of genetic differentiation were observed among populations of S. tani at five elevations. The degree of genetic diversity, however, was not in accordance with an altitudinal gradient, and a Mantel test indicated that elevation did not have a limiting effect on gene flow. No ancestral haplotype of S. tani was found among the populations. Pupae with unique structural characters at the highest elevation showed a tendency to form their own haplotype cluster, as revealed by the COII gene. Tajima’s D, Fu’s Fs, and mismatch distribution tests revealed population expansion of S. tani in Cameron Highlands. A strong correlation was found between nucleotide diversity and the levels of dissolved oxygen in the streams where S. tani was collected. PMID:24941043

Group selection on population size affects life-history patterns in the entomopathogenic nematode Steinernema carpocapsae.

PubMed

Bashey, Farrah; Lively, Curtis M

2009-05-01

Selection is recognized to operate on multiple levels. In disease organisms, selection among hosts is thought to provide an important counterbalance to selection for faster growth within hosts. We performed three experiments, each selecting for a divergence in group size in the entomopathogenic nematode, Steinernema carpocapsae. These nematodes infect and kill insect larvae, reproduce inside the host carcass, and emerge as infective juveniles. We imposed selection on group size by selecting among hosts for either high or low numbers of emerging nematodes. Our goal was to determine whether this trait could respond to selection at the group level, and if so, to examine what other traits would evolve as correlated responses. One of the three experiments showed a significant response to group selection. In that experiment, the high-selected treatment consistently produced more emerging nematodes per host than the low-selected treatment. In addition, nematodes were larger and they emerged later from hosts in the low-selected lines. Despite small effective population sizes, the effects of inbreeding were small in this experiment. Thus, selection among hosts can be effective, leading to both a direct evolutionary response at the population level, as well as to correlated responses in populational and individual traits.

Population structure and genomic inbreeding in nine Swiss dairy cattle populations.

PubMed

Signer-Hasler, Heidi; Burren, Alexander; Neuditschko, Markus; Frischknecht, Mirjam; Garrick, Dorian; Stricker, Christian; Gredler, Birgit; Bapst, Beat; Flury, Christine

2017-11-07

Domestication, breed formation and intensive selection have resulted in divergent cattle breeds that likely exhibit their own genomic signatures. In this study, we used genotypes from 27,612 autosomal single nucleotide polymorphisms to characterize population structure based on 9214 sires representing nine Swiss dairy cattle populations: Brown Swiss (BS), Braunvieh (BV), Original Braunvieh (OB), Holstein (HO), Red Holstein (RH), Swiss Fleckvieh (SF), Simmental (SI), Eringer (ER) and Evolèner (EV). Genomic inbreeding (F ROH ) and signatures of selection were determined by calculating runs of homozygosity (ROH). The results build the basis for a better understanding of the genetic development of Swiss dairy cattle populations and highlight differences between the original populations (i.e. OB, SI, ER and EV) and those that have become more popular in Switzerland as currently reflected by their larger populations (i.e. BS, BV, HO, RH and SF). The levels of genetic diversity were highest and lowest in the SF and BS breeds, respectively. Based on F ST values, we conclude that, among all pairwise comparisons, BS and HO (0.156) differ more than the other pairs of populations. The original Swiss cattle populations OB, SI, ER, and EV are clearly genetically separated from the Swiss cattle populations that are now more common and represented by larger numbers of cows. Mean levels of F ROH ranged from 0.027 (ER) to 0.091 (BS). Three of the original Swiss cattle populations, ER (F ROH : 0.027), OB (F ROH : 0.029), and SI (F ROH : 0.039), showed low levels of genomic inbreeding, whereas it was much higher in EV (F ROH : 0.074). Private signatures of selection for the original Swiss cattle populations are reported for BTA4, 5, 11 and 26. The low levels of genomic inbreeding observed in the original Swiss cattle populations ER, OB and SI compared to the other breeds are explained by a lesser use of artificial insemination and greater use of natural service. Natural service results in more sires having progeny at each generation and thus this breeding practice is likely the major reason for the remarkable levels of genetic diversity retained within these populations. The fact that the EV population is regionally restricted and its small census size of herd-book cows explain its high level of genomic inbreeding.

Characterization of [(3)H]harmane binding to rat whole brain membranes.

PubMed

Anderson, N J; Robinson, E S J; Husbands, S M; Delagrange, P; Nutt, D J; Hudson, A L

2003-12-01

This study investigates the binding of [(3)H]harmane to rat whole brain homogenates. Saturation studies revealed [(3)H]harmane labels a single, saturable, high-capacity population with high affinity. All the test compounds displaced [(3)H]harmane completely and in an apparently monophasic manner. The displacement profile of the test ligands indicated labeling of MAO-A. Given the high level of MAO-A binding, it is unlikely that a low-capacity I(2) site would be distinguishable from the total [(3)H]harmane population.

Women with high early pregnancy urinary iodine levels have an increased risk of hyperthyroid newborns: the population-based Generation R Study.

PubMed

Medici, Marco; Ghassabian, Akhgar; Visser, Willy; de Muinck Keizer-Schrama, Sabine M P F; Jaddoe, Vincent W V; Visser, W Edward; Hooijkaas, Herbert; Hofman, Albert; Steegers, Eric A P; Bongers-Schokking, Jacoba J; Ross, H Alec; Tiemeier, Henning; Visser, Theo J; de Rijke, Yolanda B; Peeters, Robin P

2014-04-01

Iodine deficiency during pregnancy results in thyroid dysfunction and has been associated with adverse obstetric and foetal effects, leading to worldwide salt iodization programmes. As nowadays 69% of the world's population lives in iodine-sufficient regions, we investigated the effects of variation in iodine status on maternal and foetal thyroid (dys)function in an iodine-sufficient population. Urinary iodine, serum TSH, free T4 (FT4) and TPO-antibody levels were determined in early pregnancy (13·3 (1·9) week; mean (SD)) in 1098 women from the population-based Generation R Study. Newborn cord serum TSH and FT4 levels were determined at birth. The median urinary iodine level was 222·5 μg/l, indicating an iodine-sufficient population. 30·8% and 11·5% had urinary iodine levels <150 and >500 μg/l, respectively. When comparing mothers with urinary iodine levels <150 vs ≥150 μg/l, and >500 vs ≤500 μg/l, there were no differences in the risk of maternal increased or decreased TSH, hypothyroxinaemia or hyperthyroidism. Mothers with urinary iodine levels >500 μg/l had a higher risk of a newborn with decreased cord TSH levels (5·6 ± 1·4 (mean ± SE) vs 2·1 ± 0·5%, P = 0·04), as well as a higher risk of a hyperthyroid newborn (3·1 ± 0·9 vs 0·6 ± 0·3%, P = 0·02). These mothers had newborns with higher cord FT4 levels (21·7 ± 0·3 vs 21·0 ± 0·1 pm, P = 0·04). Maternal urinary iodine levels <150 μg/l were not associated with newborn thyroid dysfunction. In an iodine-sufficient population, higher maternal urinary iodine levels are associated with an increased risk of a hyperthyroid newborn. © 2013 John Wiley & Sons Ltd.

No variation and low synonymous substitution rates in coral mtDNA despite high nuclear variation

PubMed Central

Hellberg, Michael E

2006-01-01

Background The mitochondrial DNA (mtDNA) of most animals evolves more rapidly than nuclear DNA, and often shows higher levels of intraspecific polymorphism and population subdivision. The mtDNA of anthozoans (corals, sea fans, and their kin), by contrast, appears to evolve slowly. Slow mtDNA evolution has been reported for several anthozoans, however this slow pace has been difficult to put in phylogenetic context without parallel surveys of nuclear variation or calibrated rates of synonymous substitution that could permit quantitative rate comparisons across taxa. Here, I survey variation in the coding region of a mitochondrial gene from a coral species (Balanophyllia elegans) known to possess high levels of nuclear gene variation, and estimate synonymous rates of mtDNA substitution by comparison to another coral (Tubastrea coccinea). Results The mtDNA surveyed (630 bp of cytochrome oxidase subunit I) was invariant among individuals sampled from 18 populations spanning 3000 km of the range of B. elegans, despite high levels of variation and population subdivision for allozymes over these same populations. The synonymous substitution rate between B. elegans and T. coccinea (0.05%/site/106 years) is similar to that in most plants, but 50–100 times lower than rates typical for most animals. In addition, while substitutions to mtDNA in most animals exhibit a strong bias toward transitions, mtDNA from these corals does not. Conclusion Slow rates of mitochondrial nucleotide substitution result in low levels of intraspecific mtDNA variation in corals, even when nuclear loci vary. Slow mtDNA evolution appears to be the basal condition among eukaryotes. mtDNA substitution rates switch from slow to fast abruptly and unidirectionally. This switch may stem from the loss of just one or a few mitochondrion-specific DNA repair or replication genes. PMID:16542456

Levels of Critical Thinking of Secondary Agriculture Students.

ERIC Educational Resources Information Center

Rollins, Timothy J.

1990-01-01

A total of 668 Iowa secondary agriculture students completed the Cornell Critical Thinking Test Level X. These scores and data from the Iowa Tests of Educational Development (ITED) revealed levels of proficiency comparable to other high school populations. The best indicator of critical thinking score was the ITED subtest Reading Total. (SK)

Trans fatty acids and cholesterol levels: an evidence map of the available science

USDA-ARS?s Scientific Manuscript database

High intakes of industrial trans fatty acids (iTFA) increase circulating low density lipoprotein cholesterol (LDL-C) levels, which has implicated iTFA in coronary heart disease (CHD) risk. Published data on iTFA and LDL-C, however, represent higher intake levels than the U.S. population currently co...

Students' Critical Thinking Ability: Description Based on Academic Level and Gender

ERIC Educational Resources Information Center

Zetriuslita, Hj.; Ariawan, Rezi; Nufus, Hayatun

2016-01-01

This research aims to describe students' critical thinking ability based on the level academic and gender. The populations of this study were 132 students participating in five classes of Calculus course. The research data obtained through technical tests and interview techniques. This study found that the high level of capability, both male…

Social determinants of denture/bridge use: Japan gerontological evaluation study project cross-sectional study in older Japanese.

PubMed

Yamamoto, Tatsuo; Kondo, Katsunori; Aida, Jun; Suzuki, Kayo; Misawa, Jimpei; Nakade, Miyo; Fuchida, Shinya; Hirata, Yukio

2014-06-03

Studies suggest that using a denture/bridge may prevent disability in older people. However, not all older people with few remaining teeth use a denture/bridge. This cross-sectional study aimed to examine the social determinants which promote denture/bridge use among older Japanese. A total of 54,388 (25,630 males and 28,758 females) community-dwelling individuals aged 65 or over, living independently, able to perform daily activities, and with 19 or fewer teeth. The dependent variable was denture/bridge use. Socio-demographics, number of teeth, present illness, social participation, social support, and social networks were used as individual-level independent variables. Data for social capital were aggregated and used as local district (n = 561 for males, n = 562 for females) -level independent variables. Number of dentists working in hospitals/clinics per population and population density were used as municipality (n = 28) -level independent variables. Three-level multilevel Poisson regression analysis was performed for each sex. High equivalent income, low number of teeth, present illness, and living in a municipality with high population density were significantly associated with denture/bridge use in both sexes in the fully adjusted models (p < 0.05). Denture/bridge use was significantly associated with high educational attainment in males and participating in social groups in females in the fully adjusted model (p < 0.05). No significant associations were observed between denture/bridge use and social capital. Denture/bridge use was significantly associated with high economic status and present illness in both sexes, high educational attainment in males, and participation in social groups in females among community-dwelling older Japanese after adjusting for possible confounders.

The impact of development and population policies on fertility in India.

PubMed

Jain, A K

1985-01-01

This article examines the impact of development and population policies on fertility decline and regional variations in India during the 1970s. Indicators of development at the household level include female literacy and education, infant mortality, and poverty; at the village level they include availability of such social services as schools, medical facilities, and transportation and communication facilities. Multiple regression analysis of data aggregated at the state level demonstrates that conditions conducive to fertility decline include high adult female literacy and low infant mortality as indicators of social development, and high contraceptive use and, to a lesser extent, high female age at marriage as proximate determinants of fertility. There are reasons to believe that India's national family planning program contributed to the decline in fertility observed since the 1960s. The pace of fertility decline in the future will depend upon the pace of infant mortality decline, enhancement in female education, and improvements in family planning programs.

Genetic diversity, population structure, and traditional culture of Camellia reticulata.

PubMed

Xin, Tong; Huang, Weijuan; De Riek, Jan; Zhang, Shuang; Ahmed, Selena; Van Huylenbroeck, Johan; Long, Chunlin

2017-11-01

Camellia reticulata is an arbor tree that has been cultivated in southwestern China by various sociolinguistic groups for esthetic purposes as well as to derive an edible seed oil. This study examined the influence of management, socio-economic factors, and religion on the genetic diversity patterns of Camellia reticulata utilizing a combination of ethnobotanical and molecular genetic approaches. Semi-structured interviews and key informant interviews were carried out with local communities in China's Yunnan Province. We collected plant material ( n  = 190 individuals) from five populations at study sites using single-dose AFLP markers in order to access the genetic diversity within and between populations. A total of 387 DNA fragments were produced by four AFLP primer sets. All DNA fragments were found to be polymorphic (100%). A relatively high level of genetic diversity was revealed in C. reticulata samples at both the species ( H sp  = 0.3397, I sp  = 0.5236) and population (percentage of polymorphic loci = 85.63%, H pop  = 0.2937, I pop  = 0.4421) levels. Findings further revealed a relatively high degree of genetic diversity within C. reticulata populations (Analysis of Molecular Variance = 96.31%). The higher genetic diversity within populations than among populations of C. reticulata from different geographies is likely due to the cultural and social influences associated with its long cultivation history for esthetic and culinary purposes by diverse sociolinguistic groups. This study highlights the influence of human management, socio-economic factors, and other cultural variables on the genetic and morphological diversity of C. reticulata at a regional level. Findings emphasize the important role of traditional culture on the conservation and utilization of plant genetic diversity.

Patterns of range-wide genetic variation in six North American bumble bee (Apidae: Bombus) species.

PubMed

Lozier, Jeffrey D; Strange, James P; Stewart, Isaac J; Cameron, Sydney A

2011-12-01

The increasing evidence for population declines in bumble bee (Bombus) species worldwide has accelerated research efforts to explain losses in these important pollinators. In North America, a number of once widespread Bombus species have suffered serious reductions in range and abundance, although other species remain healthy. To examine whether declining and stable species exhibit different levels of genetic diversity or population fragmentation, we used microsatellite markers to genotype populations sampled across the geographic distributions of two declining (Bombus occidentalis and Bombus pensylvanicus) and four stable (Bombus bifarius; Bombus vosnesenskii; Bombus impatiens and Bombus bimaculatus) Bombus species. Populations of declining species generally have reduced levels of genetic diversity throughout their range compared to codistributed stable species. Genetic diversity can be affected by overall range size and degree of isolation of local populations, potentially confounding comparisons among species in some cases. We find no evidence for consistent differences in gene flow among stable and declining species, with all species exhibiting weak genetic differentiation over large distances (e.g. >1000 km). Populations on islands and at high elevations experience relatively strong genetic drift, suggesting that some conditions lead to genetic isolation in otherwise weakly differentiated species. B. occidentalis and B. bifarius exhibit stronger genetic differentiation than the other species, indicating greater phylogeographic structure consistent with their broader geographic distributions across topographically complex regions of western North America. Screening genetic diversity in North American Bombus should prove useful for identifying species that warrant monitoring, and developing management strategies that promote high levels of gene flow will be a key component in efforts to maintain healthy populations. © 2011 Blackwell Publishing Ltd.

Cancer understanding among Japanese students based on a nationwide survey.

PubMed

Sugisaki, Koshu; Ueda, Seiji; Monobe, Hirofumi; Yako-Suketomo, Hiroko; Eto, Takashi; Watanabe, Masaki; Mori, Ryoichi

2014-11-01

The objective of this study was to determine cancer understanding among Japanese primary and secondary school students. The study design was a cross-sectional nationwide survey using a self-administered questionnaire. The prefecture with the lowest student population was set to 1, and that with the highest student population was set to 18 for elementary schools and 19 for junior high and high schools based on the ratio of the student population. In this way, 213 elementary schools, 222 junior high schools, and 208 high schools were selected from all 47 prefectures in Japan, and questionnaires were sent to each school. The questionnaire listed the names of 15 cancers and asked respondents to choose one answer from three: "Never heard of," "Heard of/Don't understand," or "Heard of/Understand." Response rates for schools were 44.1 % (n = 94) for elementary schools, 46.4 % (n = 103) for junior high schools, and 55.8 % (n = 116) for high schools. A total of 8,876 questionnaires were used for the analysis. Our survey suggests that the most commonly understood types of cancer differed by grade, with lung cancer the most commonly understood in elementary school, leukemia in junior high schools, and breast cancer in high schools. Girls tended to demonstrate greater cancer understanding than boys, with particularly large differences by gender in rates of understanding of breast and uterine cancer at each assessed grade level. Here, we examined Japanese primary and secondary school students. Marked differences in cancer recognition by grade and gender suggest that educational efforts are needed at various grade levels and gender-specific cancer education. Further, more than 50 % of students at any school level were not familiar with most cancers. It suggests that cancer education is deficient.

Genomic Footprints of Selective Sweeps from Metabolic Resistance to Pyrethroids in African Malaria Vectors Are Driven by Scale up of Insecticide-Based Vector Control.

PubMed

Barnes, Kayla G; Weedall, Gareth D; Ndula, Miranda; Irving, Helen; Mzihalowa, Themba; Hemingway, Janet; Wondji, Charles S

2017-02-01

Insecticide resistance in mosquito populations threatens recent successes in malaria prevention. Elucidating patterns of genetic structure in malaria vectors to predict the speed and direction of the spread of resistance is essential to get ahead of the 'resistance curve' and to avert a public health catastrophe. Here, applying a combination of microsatellite analysis, whole genome sequencing and targeted sequencing of a resistance locus, we elucidated the continent-wide population structure of a major African malaria vector, Anopheles funestus. We identified a major selective sweep in a genomic region controlling cytochrome P450-based metabolic resistance conferring high resistance to pyrethroids. This selective sweep occurred since 2002, likely as a direct consequence of scaled up vector control as revealed by whole genome and fine-scale sequencing of pre- and post-intervention populations. Fine-scaled analysis of the pyrethroid resistance locus revealed that a resistance-associated allele of the cytochrome P450 monooxygenase CYP6P9a has swept through southern Africa to near fixation, in contrast to high polymorphism levels before interventions, conferring high levels of pyrethroid resistance linked to control failure. Population structure analysis revealed a barrier to gene flow between southern Africa and other areas, which may prevent or slow the spread of the southern mechanism of pyrethroid resistance to other regions. By identifying a genetic signature of pyrethroid-based interventions, we have demonstrated the intense selective pressure that control interventions exert on mosquito populations. If this level of selection and spread of resistance continues unabated, our ability to control malaria with current interventions will be compromised.

Risk factors for development of multiple-class resistance to Streptococcus pneumoniae Strains in Belgium over a 10-year period: antimicrobial consumption, population density, and geographic location.

PubMed

Van Eldere, Johan; Mera, Robertino M; Miller, Linda A; Poupard, James A; Amrine-Madsen, Heather

2007-10-01

We investigated the impact of the usage of antibiotics in ambulatory patients in Belgium in 147 defined geographical circumscriptions and at the individual isolate level. The study included 14,448 Streptococcus pneumoniae strains collected by the Belgium national reference lab from 1994 to 2004. Additional risk factors for resistance, such as population density/structure and day care attendance, were investigated for the same time-space window. A statistical model that included resistance to two or more antimicrobial classes offered the best fit for measuring the changes in nonsusceptibility to penicillin, macrolides, and tetracycline over time and place in Belgium. Analysis at the geographic level identified antimicrobial consumption with a 1-year lag (0.5% increase per additional defined daily dose) and population density as independent predictors of multiple resistance. Independent risk factors at the isolate level were age (odds ratio [OR], 1.55 for children aged <5 years), population density (7% increase in multiple resistance per 100 inhabitants/km(2)), conjugate 7-valent vaccine serotype (OR, 14.3), location (OR, 1.55 for regions bordering high-resistance France), and isolate source (OR, 1.54 for ear isolates). The expansion of multiple-resistant strains explains most of the overall twofold increase and subsequent decrease in single antimicrobial resistance between 1994 and 2004. We conclude that factors in addition to antibiotic use, such as high population density and proximity to high-resistance regions, favor multiple resistance. Regional resistance rates are not linearly related to actual antibiotic use but are linked to past antibiotic use plus a combination of demographic and geographic factors.

Restricted mating dispersal and strong breeding group structure in a mid-sized marsupial mammal (Petrogale penicillata).

PubMed

Hazlitt, S L; Sigg, D P; Eldridge, M D B; Goldizen, A W

2006-09-01

Ecological genetic studies have demonstrated that spatial patterns of mating dispersal, the dispersal of gametes through mating behaviour, can facilitate inbreeding avoidance and strongly influence the structure of populations, particularly in highly philopatric species. Elements of breeding group dynamics, such as strong structuring and sex-biased dispersal among groups, can also minimize inbreeding and positively influence levels of genetic diversity within populations. Rock-wallabies are highly philopatric mid-sized mammals whose strong dependence on rocky terrain has resulted in series of discreet, small colonies in the landscape. Populations show no signs of inbreeding and maintain high levels of genetic diversity despite strong patterns of limited gene flow within and among colonies. We used this species to investigate the importance of mating dispersal and breeding group structure to inbreeding avoidance within a 'small' population. We examined the spatial patterns of mating dispersal, the extent of kinship within breeding groups, and the degree of relatedness among brush-tailed rock-wallaby breeding pairs within a colony in southeast Queensland. Parentage data revealed remarkably restricted mating dispersal and strong breeding group structuring for a mid-sized mammal. Breeding groups showed significant levels of female kinship with evidence of male dispersal among groups. We found no evidence for inbreeding avoidance through mate choice; however, anecdotal data suggest the importance of life history traits to inbreeding avoidance between first-degree relatives. We suggest that the restricted pattern of mating dispersal and strong breeding group structuring facilitates inbreeding avoidance within colonies. These results provide insight into the population structure and maintenance of genetic diversity within colonies of the threatened brush-tailed rock-wallaby.

Genetic and phenotypic differentiation of an Andean intermediate altitude population

PubMed Central

Eichstaedt, Christina A; Antão, Tiago; Cardona, Alexia; Pagani, Luca; Kivisild, Toomas; Mormina, Maru

2015-01-01

Highland populations living permanently under hypobaric hypoxia have been subject of extensive research because of the relevance of their physiological adaptations for the understanding of human health and disease. In this context, what is considered high altitude is a matter of interpretation and while the adaptive processes at high altitude (above 3000 m) are well documented, the effects of moderate altitude (below 3000 m) on the phenotype are less well established. In this study, we compare physiological and anthropometric characteristics as well as genetic variations in two Andean populations: the Calchaquíes (2300 m) and neighboring Collas (3500 m). We compare their phenotype and genotype to the sea-level Wichí population. We measured physiological (heart rate, oxygen saturation, respiration rate, and lung function) as well as anthropometric traits (height, sitting height, weight, forearm, and tibia length). We conducted genome-wide genotyping on a subset of the sample (n = 74) and performed various scans for positive selection. At the phenotypic level (n = 179), increased lung capacity stood out in both Andean groups, whereas a growth reduction in distal limbs was only observed at high altitude. At the genome level, Calchaquíes revealed strong signals around PRKG1, suggesting that the nitric oxide pathway may be a target of selection. PRKG1 was highlighted by one of four selection tests among the top five genes using the population branch statistic. Selection tests results of Collas were reported previously. Overall, our study shows that some phenotypic and genetic differentiation occurs at intermediate altitude in response to moderate lifelong selection pressures. PMID:25948820

Effects of population succession on demographic and genetic processes: predictions and tests in the daylily Hemerocallis thunbergii (Liliaceae).

PubMed

Chung, Mi Yoon; Nason, John D; Chung, Myong Gi

2007-07-01

Spatial genetic structure within plant populations is influenced by variation in demographic processes through space and time, including a population's successional status. To determine how demographic structure and fine-scale genetic structure (FSGS) change with stages in a population's successional history, we studied Hemerocallis thunbergii (Liliaceae), a nocturnal flowering and hawkmoth-pollinated herbaceous perennial with rapid population turnover dynamics. We examined nine populations assigned to three successive stages of population succession: expansion, maturation, and senescence. We developed stage-specific expectations for within-population demographic and genetic structure, and then for each population quantified the spatial aggregation of individuals and genotypes using spatial autocorrelation methods (nonaccumulative O-ring and kinship statistics, respectively), and at the landscape level measured inbreeding and genetic structure using Wright's F-statistics. Analyses using the O-ring statistic revealed significant aggregation of individuals at short spatial scales in expanding and senescing populations, in particular, which may reflect restricted seed dispersal around maternal individuals combined with relatively low local population densities at these stages. Significant FSGS was found for three of four expanding, no mature, and only one senescing population, a pattern generally consistent with expectations of successional processes. Although allozyme genetic diversity was high within populations (mean %P = 78.9 and H(E) = 0.281), landscape-level differentiation among sites was also high (F(ST) = 0.166) and all populations exhibited a significant deficit of heterozygotes relative to Hardy-Weinberg expectations (range F = 0.201-0.424, mean F(IS) = 0.321). Within populations, F was not correlated with the degree of FSGS, thus suggesting inbreeding due primarily to selfing as opposed to mating among close relatives in spatially structured populations. Our results demonstrate considerable variation in the spatial distribution of individuals and patterns and magnitude of FSGS in H. thunbergii populations across the landscape. This variation is generally consistent with succession-stage-specific differences in ecological processes operating within these populations.

Phylogeography of the sponge Suberites diversicolor in Indonesia: insights into the evolution of marine lake populations.

PubMed

Becking, Leontine E; Erpenbeck, Dirk; Peijnenburg, Katja T C A; de Voogd, Nicole J

2013-01-01

The existence of multiple independently derived populations in landlocked marine lakes provides an opportunity for fundamental research into the role of isolation in population divergence and speciation in marine taxa. Marine lakes are landlocked water bodies that maintain a marine character through narrow submarine connections to the sea and could be regarded as the marine equivalents of terrestrial islands. The sponge Suberites diversicolor (Porifera: Demospongiae: Suberitidae) is typical of marine lake habitats in the Indo-Australian Archipelago. Four molecular markers (two mitochondrial and two nuclear) were employed to study genetic structure of populations within and between marine lakes in Indonesia and three coastal locations in Indonesia, Singapore and Australia. Within populations of S. diversicolor two strongly divergent lineages (A & B) (COI: p = 0.4% and ITS: p = 7.3%) were found, that may constitute cryptic species. Lineage A only occurred in Kakaban lake (East Kalimantan), while lineage B was present in all sampled populations. Within lineage B, we found low levels of genetic diversity in lakes, though there was spatial genetic population structuring. The Australian population is genetically differentiated from the Indonesian populations. Within Indonesia we did not record an East-West barrier, which has frequently been reported for other marine invertebrates. Kakaban lake is the largest and most isolated marine lake in Indonesia and contains the highest genetic diversity with genetic variants not observed elsewhere. Kakaban lake may be an area where multiple putative refugia populations have come into secondary contact, resulting in high levels of genetic diversity and a high number of endemic species.

Phylogeography of the Sponge Suberites diversicolor in Indonesia: Insights into the Evolution of Marine Lake Populations

PubMed Central

Becking, Leontine E.; Erpenbeck, Dirk; Peijnenburg, Katja T. C. A.; de Voogd, Nicole J.

2013-01-01

The existence of multiple independently derived populations in landlocked marine lakes provides an opportunity for fundamental research into the role of isolation in population divergence and speciation in marine taxa. Marine lakes are landlocked water bodies that maintain a marine character through narrow submarine connections to the sea and could be regarded as the marine equivalents of terrestrial islands. The sponge Suberites diversicolor (Porifera: Demospongiae: Suberitidae) is typical of marine lake habitats in the Indo-Australian Archipelago. Four molecular markers (two mitochondrial and two nuclear) were employed to study genetic structure of populations within and between marine lakes in Indonesia and three coastal locations in Indonesia, Singapore and Australia. Within populations of S. diversicolor two strongly divergent lineages (A & B) (COI: p = 0.4% and ITS: p = 7.3%) were found, that may constitute cryptic species. Lineage A only occurred in Kakaban lake (East Kalimantan), while lineage B was present in all sampled populations. Within lineage B, we found low levels of genetic diversity in lakes, though there was spatial genetic population structuring. The Australian population is genetically differentiated from the Indonesian populations. Within Indonesia we did not record an East-West barrier, which has frequently been reported for other marine invertebrates. Kakaban lake is the largest and most isolated marine lake in Indonesia and contains the highest genetic diversity with genetic variants not observed elsewhere. Kakaban lake may be an area where multiple putative refugia populations have come into secondary contact, resulting in high levels of genetic diversity and a high number of endemic species. PMID:24098416

High levels of diversity and population structure in the potato late blight pathogen at the Mexico centre of origin.

PubMed

Wang, Jianan; Fernández-Pavía, Sylvia P; Larsen, Meredith M; Garay-Serrano, Edith; Gregorio-Cipriano, Rosario; Rodríguez-Alvarado, Gerardo; Grünwald, Niklaus J; Goss, Erica M

2017-02-01

Globally destructive crop pathogens often emerge by migrating out of their native ranges. These pathogens are often diverse at their centre of origin and may exhibit adaptive variation in the invaded range via multiple introductions from different source populations. However, source populations are generally unidentified or poorly studied compared to invasive populations. Phytophthora infestans, the causal agent of late blight, is one of the most costly pathogens of potato and tomato worldwide. Mexico is the centre of origin and diversity of P. infestans and migration events out of Mexico have enormously impacted disease dynamics in North America and Europe. The debate over the origin of the pathogen, and population studies of P. infestans in Mexico, has focused on the Toluca Valley, whereas neighbouring regions have been little studied. We examined the population structure of P. infestans across central Mexico, including samples from Michoacán, Tlaxcala and Toluca. We found high levels of diversity consistent with sexual reproduction in Michoacán and Tlaxcala and population subdivision that was strongly associated with geographic region. We determined that population structure in central Mexico has contributed to diversity in introduced populations based on relatedness of U.S. clonal lineages to Mexican isolates from different regions. Our results suggest that P. infestans exists as a metapopulation in central Mexico, and this population structure could be contributing to the repeated re-emergence of P. infestans in the United States and elsewhere. © 2016 John Wiley & Sons Ltd.

Genetic diversity and conservation status of managed vicuña (Vicugna vicugna) populations in Argentina.

PubMed

Anello, M; Daverio, M S; Romero, S R; Rigalt, F; Silbestro, M B; Vidal-Rioja, L; Di Rocco, F

2016-02-01

The vicuña (Vicugna vicugna) was indiscriminately hunted for more than 400 years and, by the end of 1960s, it was seriously endangered. At that time, a captive breeding program was initiated in Argentina by the National Institute of Agricultural Technology (INTA) with the aim of preserving the species. Nowadays, vicuñas are managed in captivity and in the wild to obtain their valuable fiber. The current genetic status of Argentinean vicuña populations is virtually unknown. Using mitochondrial DNA and microsatellite markers, we assessed levels of genetic diversity of vicuña populations managed in the wild and compared it with a captive population from INTA. Furthermore, we examined levels of genetic structure and evidence for historical bottlenecks. Overall, all populations revealed high genetic variability with no signs of inbreeding. Levels of genetic diversity between captive and wild populations were not significantly different, although the captive population showed the lowest estimates of allelic richness, number of mitochondrial haplotypes, and haplotype diversity. Significant genetic differentiation at microsatellite markers was found between free-living populations from Jujuy and Catamarca provinces. Moreover, microsatellite data also revealed genetic structure within the Catamarca management area. Genetic signatures of past bottlenecks were detected in wild populations by the Garza Williamson test. Results from this study are discussed in relation to the conservation and management of the species.

ACE, APOA5, and MTP Gene Polymorphisms Analysis in Relation to Triglyceride and Insulin Levels in Pediatric Patients.

PubMed

Carranza-González, Lilia; León-Cachón, Rafael B R; González-Zavala, María Antonia; Ríos-Ibarra, Clara; Morlett-Chávez, Jesús; Sánchez-Domínguez, Celia; Cepeda-Nieto, Ana; Salinas-Santander, Mauricio

2018-04-25

Obesity is a complex, chronic, and multifactorial disease that has become a major, and worldwide, public health problem contributing to an increased number of pathologies, including type 2 diabetes, cardiovascular disease, hyperlipidemia, and metabolic syndrome, thus suggesting a commolon origin. A diet high in sugar and fats coupled with a sedentary lifestyle has a major role in the development of obesity. However, the genetic background has also been associated with body fat accumulation. The aim of this study was to assess the effect ofACE-rs4646994, APOA5-rs662799, and MTP-rs1800591 gene polymorphisms on clinical and biochemical parameters and to evaluate the association with body phenotypes in children and adolescent population of Saltillo, Coahuila, Mexico. Anthropometric, clinical, biochemical parameters and BMI were obtained from 405 children and adolescents. The BMI was used to determine the body phenotype. The rs4646994 gene polymorphism was determined by PCR, whereas rs662799 and rs1800591 were determined by PCR-RFLP. The obtained results were analyzed to determine their association of these single nucleotide polymorphisms with body phenotype and biochemical parameters. TT genotype for APOA5-rs662799 was associated with increased levels of HDL-C in the analyzed population (p <0.05). The ACErs4646994gene polymorphism is associated with high Insulin levels, HOMAIR index, and triglyceride levels, mainly when presenting a I/I genotype (p <0.05). The polymorphic allele of the ACE gene is capable of modulating triglyceride levels, insulin levels and HOMA-IR index in the evaluated population; it must be highlighted that this has not been reported in other studied populations elsewhere. Copyright © 2018 IMSS. Published by Elsevier Inc. All rights reserved.

Tsunami vulnerability assessment in the western coastal belt in Sri Lanka

NASA Astrophysics Data System (ADS)

Ranagalage, M. M.

2017-12-01

26th December 2004 tsunami disaster has caused massive loss of life, damage to coastal infrastructures and disruption to economic activities in the coastal belt of Sri Lanka. Tsunami vulnerability assessment is a requirement for disaster risk and vulnerability reduction. It plays a major role in identifying the extent and level of vulnerabilities to disasters within the communities. There is a need for a clearer understanding of the disaster risk patterns and factors contributing to it in different parts of the coastal belt. The main objective of this study is to investigate tsunami vulnerability assessment of Moratuwa Municipal council area in Sri Lanka. We have selected Moratuwa area due to considering urbanization pattern and Tsunami hazards of the country. Different data sets such as one-meter resolution LiDAR data, orthophoto, population, housing data and road layer were employed in this study. We employed tsunami vulnerability model for 1796 housing units located there, for a tsunami scenario with a maximum run-up 8 meters. 86% of the total land area affected by the tsunami in 8 meters scenarios. Additionally, building population has been used to estimate population in different vulnerability levels. The result shows that 32% of the buildings have extremely critical vulnerability level, 46% have critical vulnerability level, 22% have high vulnerability level, and 1% have a moderate vulnerability. According to the population estimation model results, 18% reside building with extremely critical vulnerability, 43% with critical vulnerability, 36% with high vulnerability and 3% belong to moderate vulnerability level. The results of the study provide a clear picture of tsunami vulnerability. Outcomes of this analysis can use as a valuable tool for urban planners to assess the risk and extent of disaster risk reduction which could be achieved via suitable mitigation measures to manage the coastal belt in Sri Lanka.

Population structuring of the ubiquitous stingless bee Tetragonisca angustula in southern Brazil as revealed by microsatellite and mitochondrial markers.

PubMed

Francisco, Flávio O; Santiago, Leandro R; Mizusawa, Yuri M; Oldroyd, Benjamin P; Arias, Maria C

2017-10-01

Tetragonisca angustula is one of the most widespread stingless bees in the Neotropics. This species swarms frequently and is extremely successful in urban environments. In addition, it is one of the most popular stingless bee species for beekeeping in Latin America, so nest transportation and trading is common. Nest transportation can change the genetic structure of the host population, reducing inbreeding and increasing homogenization. Here, we evaluate the genetic structure of 17 geographic populations of T. angustula in southern Brazil to quantify the level of genetic differentiation between populations. Analyses were conducted on partially sequenced mitochondrial genes and 11 microsatellite loci of 1002 workers from 457 sites distributed on the mainland and on 3 islands. Our results show that T. angustula populations are highly differentiated as demonstrated by mitochondrial DNA (mtDNA) and microsatellite markers. Of 73 haplotypes, 67 were population-specific. MtDNA diversity was low in 9 populations but microsatellite diversity was moderate to high in all populations. Microsatellite data suggest 10 genetic clusters and low level of gene flow throughout the studied area. However, physical barriers, such as rivers and mountain ranges, or the presence or absence of forest appear to be unrelated to population clusters. Factors such as low dispersal, different ecological conditions, and isolation by distance are most likely shaping the population structure of this species. Thus far, nest transportation has not influenced the general population structure in the studied area. However, due to the genetic structure we found, we recommend that nest transportation should only occur within and between populations that are genetically similar. © 2016 Institute of Zoology, Chinese Academy of Sciences.

Herd-level bovine tuberculosis risk factors: assessing the role of low-level badger population disturbance.

PubMed

Wright, David M; Reid, Neil; Ian Montgomery, W; Allen, Adrian R; Skuce, Robin A; Kao, Rowland R

2015-08-17

Bovine TB (bTB) is endemic in Irish cattle and has eluded eradication despite considerable expenditure, amid debate over the relative roles of badgers and cattle in disease transmission. Using a comprehensive dataset from Northern Ireland (>10,000 km(2); 29,513 cattle herds), we investigated interactions between host populations in one of the first large-scale risk factor analyses for new herd breakdowns to combine data on both species. Cattle risk factors (movements, international imports, bTB history, neighbours with bTB) were more strongly associated with herd risk than area-level measures of badger social group density, habitat suitability or persecution (sett disturbance). Highest risks were in areas of high badger social group density and high rates of persecution, potentially representing both responsive persecution of badgers in high cattle risk areas and effects of persecution on cattle bTB risk through badger social group disruption. Average badger persecution was associated with reduced cattle bTB risk (compared with high persecution areas), so persecution may contribute towards sustaining bTB hotspots; findings with important implications for existing and planned disease control programmes.

Genome-wide linkage disequilibrium and genetic diversity in five populations of Australian domestic sheep.

PubMed

Al-Mamun, Hawlader Abdullah; Clark, Samuel A; Kwan, Paul; Gondro, Cedric

2015-11-24

Knowledge of the genetic structure and overall diversity of livestock species is important to maximise the potential of genome-wide association studies and genomic prediction. Commonly used measures such as linkage disequilibrium (LD), effective population size (N e ), heterozygosity, fixation index (F ST) and runs of homozygosity (ROH) are widely used and help to improve our knowledge about genetic diversity in animal populations. The development of high-density single nucleotide polymorphism (SNP) arrays and the subsequent genotyping of large numbers of animals have greatly increased the accuracy of these population-based estimates. In this study, we used the Illumina OvineSNP50 BeadChip array to estimate and compare LD (measured by r (2) and D'), N e , heterozygosity, F ST and ROH in five Australian sheep populations: three pure breeds, i.e., Merino (MER), Border Leicester (BL), Poll Dorset (PD) and two crossbred populations i.e. F1 crosses of Merino and Border Leicester (MxB) and MxB crossed to Poll Dorset (MxBxP). Compared to other livestock species, the sheep populations that were analysed in this study had low levels of LD and high levels of genetic diversity. The rate of LD decay was greater in Merino than in the other pure breeds. Over short distances (<10 kb), the levels of LD were higher in BL and PD than in MER. Similarly, BL and PD had comparatively smaller N e than MER. Observed heterozygosity in the pure breeds ranged from 0.3 in BL to 0.38 in MER. Genetic distances between breeds were modest compared to other livestock species (highest F ST = 0.063) but the genetic diversity within breeds was high. Based on ROH, two chromosomal regions showed evidence of strong recent selection. This study shows that there is a large range of genome diversity in Australian sheep breeds, especially in Merino sheep. The observed range of diversity will influence the design of genome-wide association studies and the results that can be obtained from them. This knowledge will also be useful to design reference populations for genomic prediction of breeding values in sheep.

WDR1 and CLNK gene polymorphisms correlate with serum glucose and high-density lipoprotein levels in Tibetan gout patients.

PubMed

Lan, Bing; Chen, Peng; Jiri, Mutu; He, Na; Feng, Tian; Liu, Kai; Jin, Tianbo; Kang, Longli

2016-03-01

Current evidence suggests heredity and metabolic syndrome contributes to gout progression. Specifically, the WDR1 and CLNK genes may play a role in gout progression in European ancestry populations. However, no studies have focused on Chinese populations, especially Tibetan individuals. This study aims to determine whether variations in these two genes correlate with gout-related indices in Chinese-Tibetan gout patients. Eleven single-nucleotide polymorphisms in the WDR1 and CLNK genes were detected in 319 Chinese-Tibetan gout patients and 318 controls. We used one-way analysis of variance to evaluate the polymorphisms' effects on gout based on mean serum levels of metabolism indicators, such as albumin, glucose (GLU), triglycerides, cholesterol, high-density lipoproteins (HDL-C), creatinine, and uric acid, from fasting venous blood samples. All p values were Bonferroni corrected. Polymorphisms of the WDR1 and CLNK genes affected multiple risk factors for gout development. Significant differences in serum GLU levels were detected between different genotypic groups with WDRI polymorphisms rs4604059 (p = 0.005) and rs12498927 (p = 0.005). In addition, significant differences in serum HDL-C levels were detected between different genotypic groups with the CLNK polymorphism rs2041215 (p = 0.001). Polymorphisms of CLNK also affected levels of albumin, triglycerides, and creatinine. This study is the first to investigate and identify positive correlations between WDR1 and CLNK gene polymorphisms in Chinese-Tibetan populations. Our findings provide significant evidence for the effect of genetic polymorphisms on gout-related factors in Chinese-Tibetan populations.

Elevated serum ferritin concentration is associated with incident type 2 diabetes mellitus in a Chinese population: A prospective cohort study.

PubMed

Chen, Ling; Li, Yufeng; Zhang, Fang; Zhang, Simin; Zhou, Xianghai; Ji, Linong

2018-05-01

We aimed to evaluate the association between serum ferritin levels and incident type 2 diabetes mellitus risk in a Chinese population. This cohort study assessed 2225 Chinese individuals aged 25-75 years. Diabetes mellitus was diagnosed using the 1999 World Health Organization definition with a median follow-up period of 20 months. Cox proportional hazard models were used to estimate adjusted hazard ratios and 95% confidence intervals (CI) for incident diabetes when serum ferritin concentrations increased by one standard deviation. During the follow-up period, 112 cases (62 men and 50 women) of type 2 diabetes mellitus were identified. Baseline serum ferritin levels were higher in the diabetes than the non-diabetes group. After adjusting for age, body mass index, waist circumference, mean arterial pressure, fasting plasma glucose, fasting insulin, hemoglobin A1c, total cholesterol, high-density lipoprotein cholesterol, alanine transaminase and triglyceride levels, family history of diabetes mellitus, pork meat consumption, neutrophil/lymphocyte ratio, education, and annual household income, the hazard ratios for incident diabetes corresponding to one standard deviation increase in serum ferritin levels were 1.17 (95% CI 1.03, 1.34), 1.20 (95% CI 1.003, 1.43), and 1.03 (95% CI 0.82, 1.31) for the total population, men, and women, respectively. High serum ferritin levels were associated with a higher risk of incident type 2 diabetes mellitus independent of traditional risk factors in the total population and men. Copyright © 2018 Elsevier B.V. All rights reserved.

Mozambique.

PubMed

1982-10-01

Focus in this discussion of Mozambique is on the following: history of the demographic situation; the government's overall approach to population problems; population data systems and development planning; institutional arrangements for the integration of population within development planning; the government's view of the importance of population policy in achieving development objectives; population size, growth, and natural increase; morbidity and mortality; fertility; international migration; and spatial distribution. According to the 1970 general census, Mozambique's population totaled 8.2 million with an estimated annual rate of natural increase of 2.2%. According to the UN Population Division, the crude birthrate for the 1975-80 period was estimated at 44.8/1000 population and the crude death rate at 19.0/1000; life expectancy at birth was estimated at 46 years for both sexes. In 1974 Mozambique achieved independence. From the time of Independence, the government planners have emphasized the reconstruction of agriculture and associated elements of the rural economy. In later stages, emphasis is to be given to associated secondary industries and to construction of heavy industry. Although the government is not known to have expressed a policy with regard to the demographic situation as a whole, it has taken a position concerning some aspects of spatial distribution and emigration. The government has also formulated and implemented certain health policies that emphasize maternal and child health, family planning, and the status of women. These policies have been formulated as components of social policy. There are no institutions specifically established to integrate population with development planning. The government considers levels and trends of population growth to be satisfactory because the country's natural resources are very large given the current population. The UN estimates the level of infant mortality for 1980-85 to be high at 110 deaths/1000 live births. The government considers the levels and trends of morbidity and mortality to be unacceptable because they are too high and are among the most serious problems confronting the country. The government has launched an enthusiastic campaign to eliminate unhygienic traditions, giving priority to preventive medicine in line with the current capacity and facilities of the country. In 1980 the UN estimated the gross and net reproduction rates as 3.0 and 2.1 respectively for the 1975-80 period, the total fertility rate as 6.1, and a general fertility rate of 196/1000 women. The government considers the levels and trends of fertility to be satisfactory in relation to population growth, though it may consider them somewhat unsatisfactory in relation to family well-being. The government considers present levels and trends of emigration to be not significant and satisfactory and its present population distribution as appropriate.

Educational status and cardiovascular risk profile in Indians

PubMed Central

Reddy, K. Srinath; Prabhakaran, Dorairaj; Jeemon, Panniyammakal; Thankappan, K. R.; Joshi, Prashant; Chaturvedi, Vivek; Ramakrishnan, Lakshmy; Ahmed, Farooque

2007-01-01

The inverse graded relationship of education and risk factors of coronary heart disease (CHD) has been reported from Western populations. To examine whether risk factors of CHD are predicted by level of education and influenced by the level of urbanization in Indian industrial populations, a cross-sectional survey (n = 19,973; response rate, 87.6%) was carried out among employees and their family members in 10 medium-to-large industries in highly urban, urban, and periurban regions of India. Information on behavioral, clinical, and biochemical risk factors of CHD was obtained through standardized instruments, and educational status was assessed in terms of the highest educational level attained. Data from 19,969 individuals were used for analysis. Tobacco use and hypertension were significantly more prevalent in the low- (56.6% and 33.8%, respectively) compared with the high-education group (12.5% and 22.7%, respectively; P < 0.001). However, dyslipidemia prevalence was significantly higher in the high-education group (27.1% as compared with 16.9% in the lowest-education group; P < 0.01). When stratified by the level of urbanization, industrial populations located in highly urbanized centers were observed to have an inverse graded relationship (i.e., higher-education groups had lower prevalence) for tobacco use, hypertension, diabetes, and overweight, whereas in less-urbanized locations, we found such a relationship only for tobacco use and hypertension. This study indicates the growing vulnerability of lower socioeconomic groups to CHD. Preventive strategies to reduce major CHD risk factors should focus on effectively addressing these social disparities. PMID:17923677

Ship noise extends to frequencies used for echolocation by endangered killer whales.

PubMed

Veirs, Scott; Veirs, Val; Wood, Jason D

2016-01-01

Combining calibrated hydrophone measurements with vessel location data from the Automatic Identification System, we estimate underwater sound pressure levels for 1,582 unique ships that transited the core critical habitat of the endangered Southern Resident killer whales during 28 months between March, 2011, and October, 2013. Median received spectrum levels of noise from 2,809 isolated transits are elevated relative to median background levels not only at low frequencies (20-30 dB re 1 µPa(2)/Hz from 100 to 1,000 Hz), but also at high frequencies (5-13 dB from 10,000 to 96,000 Hz). Thus, noise received from ships at ranges less than 3 km extends to frequencies used by odontocetes. Broadband received levels (11.5-40,000 Hz) near the shoreline in Haro Strait (WA, USA) for the entire ship population were 110 ± 7 dB re 1 µPa on average. Assuming near-spherical spreading based on a transmission loss experiment we compute mean broadband source levels for the ship population of 173 ± 7 dB re 1 µPa 1 m without accounting for frequency-dependent absorption. Mean ship speed was 7.3 ± 2.0 m/s (14.1 ± 3.9 knots). Most ship classes show a linear relationship between source level and speed with a slope near +2 dB per m/s (+1 dB/knot). Spectrum, 1/12-octave, and 1/3-octave source levels for the whole population have median values that are comparable to previous measurements and models at most frequencies, but for select studies may be relatively low below 200 Hz and high above 20,000 Hz. Median source spectrum levels peak near 50 Hz for all 12 ship classes, have a maximum of 159 dB re 1 µPa(2)/Hz @ 1 m for container ships, and vary between classes. Below 200 Hz, the class-specific median spectrum levels bifurcate with large commercial ships grouping as higher power noise sources. Within all ship classes spectrum levels vary more at low frequencies than at high frequencies, and the degree of variability is almost halved for classes that have smaller speed standard deviations. This is the first study to present source spectra for populations of different ship classes operating in coastal habitats, including at higher frequencies used by killer whales for both communication and echolocation.

Epigenetic Variability in the Genetically Uniform Forest Tree Species Pinus pinea L

PubMed Central

Sáez-Laguna, Enrique; Guevara, María-Ángeles; Díaz, Luis-Manuel; Sánchez-Gómez, David; Collada, Carmen; Aranda, Ismael; Cervera, María-Teresa

2014-01-01

There is an increasing interest in understanding the role of epigenetic variability in forest species and how it may contribute to their rapid adaptation to changing environments. In this study we have conducted a genome-wide analysis of cytosine methylation pattern in Pinus pinea, a species characterized by very low levels of genetic variation and a remarkable degree of phenotypic plasticity. DNA methylation profiles of different vegetatively propagated trees from representative natural Spanish populations of P. pinea were analyzed with the Methylation Sensitive Amplified Polymorphism (MSAP) technique. A high degree of cytosine methylation was detected (64.36% of all scored DNA fragments). Furthermore, high levels of epigenetic variation were observed among the studied individuals. This high epigenetic variation found in P. pinea contrasted with the lack of genetic variation based on Amplified Fragment Length Polymorphism (AFLP) data. In this manner, variable epigenetic markers clearly discriminate individuals and differentiates two well represented populations while the lack of genetic variation revealed with the AFLP markers fail to differentiate at both, individual or population levels. In addition, the use of different replicated trees allowed identifying common polymorphic methylation sensitive MSAP markers among replicates of a given propagated tree. This set of MSAPs allowed discrimination of the 70% of the analyzed trees. PMID:25084460

Epigenetic variability in the genetically uniform forest tree species Pinus pinea L.

PubMed

Sáez-Laguna, Enrique; Guevara, María-Ángeles; Díaz, Luis-Manuel; Sánchez-Gómez, David; Collada, Carmen; Aranda, Ismael; Cervera, María-Teresa

2014-01-01

There is an increasing interest in understanding the role of epigenetic variability in forest species and how it may contribute to their rapid adaptation to changing environments. In this study we have conducted a genome-wide analysis of cytosine methylation pattern in Pinus pinea, a species characterized by very low levels of genetic variation and a remarkable degree of phenotypic plasticity. DNA methylation profiles of different vegetatively propagated trees from representative natural Spanish populations of P. pinea were analyzed with the Methylation Sensitive Amplified Polymorphism (MSAP) technique. A high degree of cytosine methylation was detected (64.36% of all scored DNA fragments). Furthermore, high levels of epigenetic variation were observed among the studied individuals. This high epigenetic variation found in P. pinea contrasted with the lack of genetic variation based on Amplified Fragment Length Polymorphism (AFLP) data. In this manner, variable epigenetic markers clearly discriminate individuals and differentiates two well represented populations while the lack of genetic variation revealed with the AFLP markers fail to differentiate at both, individual or population levels. In addition, the use of different replicated trees allowed identifying common polymorphic methylation sensitive MSAP markers among replicates of a given propagated tree. This set of MSAPs allowed discrimination of the 70% of the analyzed trees.

An Approach to Developing Local Climate Change Environmental Public Health Indicators in a Rural District

PubMed Central

2017-01-01

Climate change represents a significant and growing threat to population health. Rural areas face unique challenges, such as high rates of vulnerable populations; economic uncertainty due to their reliance on industries that are vulnerable to climate change; less resilient infrastructure; and lower levels of access to community and emergency services than urban areas. This article fills a gap in public health practice by developing climate and health environmental public health indicators for a local public health department in a rural area. We adapted the National Environmental Public Health Tracking Network's framework for climate and health indicators to a seven-county health department in Western Kentucky. Using a three-step review process, we identified primary climate-related environmental public health hazards for the region (extreme heat, drought, and flooding) and a suite of related exposure, health outcome, population vulnerability, and environmental vulnerability indicators. Indicators that performed more poorly at the county level than at the state and national level were defined as “high vulnerability.” Six to eight high vulnerability indicators were identified for each county. The local health department plans to use the results to enhance three key areas of existing services: epidemiology, public health preparedness, and community health assessment. PMID:28352286

The Changing Profile of Entrants to Mathematics at A Level and to Mathematical Subjects in Higher Education.

ERIC Educational Resources Information Center

Kitchen, Ann

1999-01-01

Analyzes the characteristics of the British student population in mathematics at both the interface between the General Certificate of Secondary Education (GCSE) and A level and between A level and high education. Focuses on the changes in GCSE and A level mathematics, entry standards in higher education, and gender balance issues. (CMK)

Expression of the cytochrome P450s, CYP6P3 and CYP6M2 are significantly elevated in multiple pyrethroid resistant populations of Anopheles gambiae s.s. from Southern Benin and Nigeria

PubMed Central

Djouaka, Rousseau F; Bakare, Adekunle A; Coulibaly, Ousmane N; Akogbeto, Martin C; Ranson, Hilary; Hemingway, Janet; Strode, Clare

2008-01-01

Background Insecticide resistance in Anopheles mosquitoes is threatening the success of malaria control programmes. This is particularly true in Benin where pyrethroid resistance has been linked to the failure of insecticide treated bed nets. The role of mutations in the insecticide target sites in conferring resistance has been clearly established. In this study, the contribution of other potential resistance mechanisms was investigated in Anopheles gambiae s.s. from a number of localities in Southern Benin and Nigeria. The mosquitoes were sampled from a variety of breeding sites in a preliminary attempt to investigate the role of contamination of mosquito breeding sites in selecting for resistance in adult mosquitoes. Results All mosquitoes sampled belonged to the M form of An. gambiae s.s. There were high levels of permethrin resistance in an agricultural area (Akron) and an urban area (Gbedjromede), low levels of resistance in mosquito samples from an oil contaminated site (Ojoo) and complete susceptibility in the rural Orogun location. The target site mutation kdrW was detected at high levels in two of the populations (Akron f = 0.86 and Gbedjromede f = 0.84) but was not detected in Ojoo or Orogun. Microarray analysis using the Anopheles gambiae detox chip identified two P450s, CYP6P3 and CYP6M2 up regulated in all three populations, the former was expressed at particularly high levels in the Akron (12.4-fold) and Ojoo (7.4-fold) populations compared to the susceptible population. Additional detoxification and redox genes were also over expressed in one or more populations including two cuticular pre-cursor genes which were elevated in two of the three resistant populations. Conclusion Multiple resistance mechanisms incurred in the different breeding sites contribute to resistance to permethrin in Benin. The cytochrome P450 genes, CYP6P3 and CYP6M2 are upregulated in all three resistant populations analysed. Several additional potential resistance mechanisms were also identified that warrant further investigation. Metabolic genes were over expressed irrespective of the presence of kdr, the latter resistance mechanism being absent in one resistant population. The discovery that mosquitoes collected from different types of breeding sites display differing profiles of metabolic genes at the adult stage may reflect the influence of a range of xenobiotics on selecting for resistance in mosquitoes. PMID:19014539

DNA methylation is differentially associated with environmental cadmium exposure based on sex and smoking status

PubMed Central

Virani, Shama; Rentschler, Katie M.; Nishijo, Muneko; Ruangyuttikarn, Werawan; Swaddiwudhipong, Witaya; Basu, Niladri; Rozek, Laura S.

2016-01-01

The adverse health effects of cadmium (Cd) are well known in human populations; however, much of what is known about biological mechanisms of Cd comes from in vitro and animal studies. The adverse health outcomes due to high levels of Cd exposure in the population of Mae Sot, Thailand have been extensively characterized. Here, for the first time, this population is being studied in an epigenetic context. The objective of this study was to characterize the association between DNA methylation markers and Cd exposure, taking into account sex and smoking differences, in an adult population at an increased risk of experiencing adverse health outcomes from high body burden of Cd. One hundred and sixty-nine residents from known exposure areas of Mae Sot, Thailand and one hundred residents from non-exposed areas nearby were surveyed in 2012. Urine and blood samples were collected for measurement of urinary Cd (UCd) and DNA methylation of Cd-related markers (DNMT3B, MGMT, LINE-1, MT2A). UCd levels were 7 times higher in the exposed compared to the unexposed populations (exposed median: 7.4 μg/L, unexposed median: 1.0 μg/L, p <0.001). MGMT hypomethylation was associated with increasing levels of UCd in the total population. Sex-specific associations included MT2A and DNMT3B hypomethylation in women and LINE-1 hypermethylation in men with increasing UCd. Upon subanalysis, these associations separated by smoking status. In summary, environmental Cd exposure is associated with gene-specific DNA methylation in a sex and smoking dependent manner. PMID:26688266

High serum selenium levels are associated with impaired fasting glucose and elevated fasting serum glucose in Linyi, China.

PubMed

Li, Zhe; Li, Xia; Ju, Wen; Wu, Guanrui; Yang, Xiaomei; Fu, Xiaofeng; Gao, Xibao

2018-01-01

The relationship between selenium level and impaired fasting glucose or elevated fasting serum glucose remains controversial. This study aimed to evaluate these associations in China. This observational population study adopted a cluster sampling approach to enroll participants. Baseline information on selenium categories was tested using one-way analysis of variance and Kruskal-Wallis equality-of-populations rank tests. Multivariable logistic regression was used to investigate the association between serum selenium level and impaired fasting glucose or elevated fasting serum glucose. The mean serum selenium concentration was 121.5μg/L which in a relatively high baseline Se status. Differences were observed among individuals with normal, impaired fasting glucose and elevated fasting serum glucose levels in their basic information, physical examination results and laboratory findings. After adjusting for their basic information, physical examination results and laboratory findings, compared with the low-selenium group, the high-selenium groups (124.9-143.9 and above 143.9μg/L) had ORs for elevated fasting serum glucose of 2.31 (1.37-3.90) and 2.67 (1.59-4.48), respectively (both P<0.05). A sex-difference was observed, and a significant association between selenium levels and impaired fasting glucose was observed for males but not for females. The findings of this observational study suggest that relatively high selenium levels might be positively associated with elevated fasting serum glucose and relatively high selenium levels might be positively associated with impaired fasting glucose in men. Copyright © 2017 Elsevier GmbH. All rights reserved.

The Evolution of Vicia ramuliflora (Fabaceae) at Tetraploid and Diploid Levels Revealed with FISH and RAPD

PubMed Central

Han, Ying; Liu, Yuan; Wang, Haoyou; Liu, Xiangjun

2017-01-01

Vicia ramuliflora L. is a widely distributed species in Eurasia with high economic value. For past 200 years, it has evolved a tetraploid cytotype and new subspecies at the diploid level. Based on taxonomy, cytogeography and other lines of evidence, previous studies have provided valuable information about the evolution of V. ramuliflora ploidy level, but due to the limited resolution of traditional methods, important questions remain. In this study, fluorescence in situ hybridization (FISH) and random amplified polymorphic DNA (RAPD) were used to analyze the evolution of V. ramuliflora at the diploid and tetraploid levels. Our aim was to reveal the genomic constitution and parents of the tetraploid V. ramuliflora and the relationships among diploid V. ramuliflora populations. Our study showed that the tetraploid cytotype of V. ramuliflora at Changbai Mountains (M) has identical 18S and 5S rDNA distribution patterns with the diploid Hengdaohezi population (B) and the diploid Dailing population (H). However, UPGMA clustering, Neighbor-Joining clustering and principal coordinates analysis based on RAPD showed that the tetraploid cytotype (M) has more close relationships with Qianshan diploid population T. Based on our results and the fact that interspecific hybridization among Vicia species is very difficult, we think that the tetraploid V. ramuliflora is an autotetraploid and its genomic origin still needs further study. In addition, our study also found that Qianshan diploid population (T) had evolved distinct new traits compared with other diploid populations, which hints that V. ramuliflora evolved further at diploid level. We suggest that diploid population T be re-classified as a new subspecies. PMID:28135314

The Evolution of Vicia ramuliflora (Fabaceae) at Tetraploid and Diploid Levels Revealed with FISH and RAPD.

PubMed

Han, Ying; Liu, Yuan; Wang, Haoyou; Liu, Xiangjun

2017-01-01

Vicia ramuliflora L. is a widely distributed species in Eurasia with high economic value. For past 200 years, it has evolved a tetraploid cytotype and new subspecies at the diploid level. Based on taxonomy, cytogeography and other lines of evidence, previous studies have provided valuable information about the evolution of V. ramuliflora ploidy level, but due to the limited resolution of traditional methods, important questions remain. In this study, fluorescence in situ hybridization (FISH) and random amplified polymorphic DNA (RAPD) were used to analyze the evolution of V. ramuliflora at the diploid and tetraploid levels. Our aim was to reveal the genomic constitution and parents of the tetraploid V. ramuliflora and the relationships among diploid V. ramuliflora populations. Our study showed that the tetraploid cytotype of V. ramuliflora at Changbai Mountains (M) has identical 18S and 5S rDNA distribution patterns with the diploid Hengdaohezi population (B) and the diploid Dailing population (H). However, UPGMA clustering, Neighbor-Joining clustering and principal coordinates analysis based on RAPD showed that the tetraploid cytotype (M) has more close relationships with Qianshan diploid population T. Based on our results and the fact that interspecific hybridization among Vicia species is very difficult, we think that the tetraploid V. ramuliflora is an autotetraploid and its genomic origin still needs further study. In addition, our study also found that Qianshan diploid population (T) had evolved distinct new traits compared with other diploid populations, which hints that V. ramuliflora evolved further at diploid level. We suggest that diploid population T be re-classified as a new subspecies.