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1

Joint Inference of Population Assignment and Demographic History  

PubMed Central

A new approach to assigning individuals to populations using genetic data is described. Most existing methods work by maximizing Hardy–Weinberg and linkage equilibrium within populations, neither of which will apply for many demographic histories. By including a demographic model, within a likelihood framework based on coalescent theory, we can jointly study demographic history and population assignment. Genealogies and population assignments are sampled from a posterior distribution using a general isolation-with-migration model for multiple populations. A measure of partition distance between assignments facilitates not only the summary of a posterior sample of assignments, but also the estimation of the posterior density for the demographic history. It is shown that joint estimates of assignment and demographic history are possible, including estimation of population phylogeny for samples from three populations. The new method is compared to results of a widely used assignment method, using simulated and published empirical data sets.

Choi, Sang Chul; Hey, Jody

2011-01-01

2

Inferring the Joint Demographic History of Multiple Populations from Multidimensional SNP Frequency Data  

Microsoft Academic Search

Demographic models built from genetic data play important roles in illuminating prehistorical events and serving as null models in genome scans for selection. We introduce an inference method based on the joint frequency spectrum of genetic variants within and between populations. For candidate models we numerically compute the expected spectrum using a diffusion approximation to the one-locus, two-allele Wright-Fisher process,

Ryan N. Gutenkunst; Ryan D. Hernandez; Scott H. Williamson; Carlos D. Bustamante

2009-01-01

3

Inferring the joint demographic history of multiple populations from multidimensional SNP frequency data  

Microsoft Academic Search

Demographic models built from genetic data play important roles in illuminating prehistorical events and serving as null models in genome scans for selection. We introduce an inference method based on the joint frequency spectrum of genetic variants within and between populations. For candidate models we numerically compute the expected spectrum using a diffusion approximation to the one-locus two-allele Wright-Fisher process,

Ryan N. Gutenkunst; Ryan D. Hernandez; Scott H. Williamson; Carlos D. Bustamante

2009-01-01

4

Inferring the Joint Demographic History of Multiple Populations from Multidimensional SNP Frequency Data  

PubMed Central

Demographic models built from genetic data play important roles in illuminating prehistorical events and serving as null models in genome scans for selection. We introduce an inference method based on the joint frequency spectrum of genetic variants within and between populations. For candidate models we numerically compute the expected spectrum using a diffusion approximation to the one-locus, two-allele Wright-Fisher process, involving up to three simultaneous populations. Our approach is a composite likelihood scheme, since linkage between neutral loci alters the variance but not the expectation of the frequency spectrum. We thus use bootstraps incorporating linkage to estimate uncertainties for parameters and significance values for hypothesis tests. Our method can also incorporate selection on single sites, predicting the joint distribution of selected alleles among populations experiencing a bevy of evolutionary forces, including expansions, contractions, migrations, and admixture. We model human expansion out of Africa and the settlement of the New World, using 5 Mb of noncoding DNA resequenced in 68 individuals from 4 populations (YRI, CHB, CEU, and MXL) by the Environmental Genome Project. We infer divergence between West African and Eurasian populations 140 thousand years ago (95% confidence interval: 40–270 kya). This is earlier than other genetic studies, in part because we incorporate migration. We estimate the European (CEU) and East Asian (CHB) divergence time to be 23 kya (95% c.i.: 17–43 kya), long after archeological evidence places modern humans in Europe. Finally, we estimate divergence between East Asians (CHB) and Mexican-Americans (MXL) of 22 kya (95% c.i.: 16.3–26.9 kya), and our analysis yields no evidence for subsequent migration. Furthermore, combining our demographic model with a previously estimated distribution of selective effects among newly arising amino acid mutations accurately predicts the frequency spectrum of nonsynonymous variants across three continental populations (YRI, CHB, CEU).

Gutenkunst, Ryan N.; Hernandez, Ryan D.; Williamson, Scott H.; Bustamante, Carlos D.

2009-01-01

5

Inferring the joint demographic history of multiple populations from multidimensional SNP frequency data.  

PubMed

Demographic models built from genetic data play important roles in illuminating prehistorical events and serving as null models in genome scans for selection. We introduce an inference method based on the joint frequency spectrum of genetic variants within and between populations. For candidate models we numerically compute the expected spectrum using a diffusion approximation to the one-locus, two-allele Wright-Fisher process, involving up to three simultaneous populations. Our approach is a composite likelihood scheme, since linkage between neutral loci alters the variance but not the expectation of the frequency spectrum. We thus use bootstraps incorporating linkage to estimate uncertainties for parameters and significance values for hypothesis tests. Our method can also incorporate selection on single sites, predicting the joint distribution of selected alleles among populations experiencing a bevy of evolutionary forces, including expansions, contractions, migrations, and admixture. We model human expansion out of Africa and the settlement of the New World, using 5 Mb of noncoding DNA resequenced in 68 individuals from 4 populations (YRI, CHB, CEU, and MXL) by the Environmental Genome Project. We infer divergence between West African and Eurasian populations 140 thousand years ago (95% confidence interval: 40-270 kya). This is earlier than other genetic studies, in part because we incorporate migration. We estimate the European (CEU) and East Asian (CHB) divergence time to be 23 kya (95% c.i.: 17-43 kya), long after archeological evidence places modern humans in Europe. Finally, we estimate divergence between East Asians (CHB) and Mexican-Americans (MXL) of 22 kya (95% c.i.: 16.3-26.9 kya), and our analysis yields no evidence for subsequent migration. Furthermore, combining our demographic model with a previously estimated distribution of selective effects among newly arising amino acid mutations accurately predicts the frequency spectrum of nonsynonymous variants across three continental populations (YRI, CHB, CEU). PMID:19851460

Gutenkunst, Ryan N; Hernandez, Ryan D; Williamson, Scott H; Bustamante, Carlos D

2009-10-01

6

Genealogy and Demographic History of a Widespread Amphibian throughout Indochina.  

PubMed

Relatively little is known about spatial patterns of cryptic diversity in tropical species and the processes that generate them. Few studies examine the geographic distribution of genetic lineages in Southeast Asia, an area hypothesized to harbor substantial cryptic diversity. We investigated the evolutionary history of Asian tree frogs of the Polypedates leucomystax complex (n = 172) based on 1800 bp of the mtDNA genes ND1 and cytochrome b and tested hypotheses pertaining to climate, geology, and dispersal patterns. Analyses revealed substantial genetic diversity and lineage divergence throughout the region with evidence for widespread sympatric lineages and a general north versus south clustering. Relaxed molecular clock analysis and tests for demographic expansion identified an initial cladogenesis during the Miocene with subsequent Plio-Pleistocene diversification, with the former corresponding to periods of increased aridity and the onset of monsoonal weather systems. Rates of diversification were relatively constant until the Early Pleistocene when rates increased exponentially. We found equivocal evidence for isolation-by-distance and a potential role of some landscape features as partial barriers to dispersal. Finally, our analyses showed that divergence between insular and mainland populations occurred before Homo sapiens colonized Southeast Asia, suggesting that historical human-mediated dispersal did not drive insular diversification. Our results suggested that demographic expansion in the Late Pleistocene resulted in widespread sympatric lineages in the P. leucomystax complex throughout southern China and Indochina and further clarified the evolutionary history of lineages within P. leucomystax. PMID:23125408

Blair, Christopher; Davy, Christina M; Ngo, Andre; Orlov, Nikolai L; Shi, Hai-tao; Lu, Shun-qing; Gao, Lan; Rao, Ding-qi; Murphy, Robert W

2013-01-01

7

Demographic history and linkage disequilibrium in human populations.  

PubMed

In the human genome, linkage disequilibrium (LD)--the non-random association of alleles at chromosomal loci--has been studied mainly in regions surrounding disease genes on affected chromosomes. Consequently, little information is available on the distribution of LD across anonymous genomic regions in the general population. However, demographic history is expected to influence the extent of overall LD across the genome, so a population that has been of constant size will display higher levels of LD than a population that has expanded. In support of this, the extent of LD between anonymous loci on chromosome 4 in chimpanzees (as a model of a population of constant size) has been compared to that in Finns (as a model of an expanded population; refs 8,9) and found to exhibit more LD than in the latter population. In Europe, studies of mitochondrial (mt) DNA sequences have suggested that most populations have experienced expansion, whereas the Saami in northern Fenno-Scandinavia have been of constant size (Table 1). Thus, in northern Europe, populations with radically different demographic histories live in close geographic proximity to each other. We studied the allelic associations between anonymous microsatellite loci on the X chromosome in the Saami and neighbouring populations and found dramatically higher levels of LD in the Saami than in other populations in the region. This indicates that whereas recently expanded populations, such as the Finns, are well suited to map single disease genes affected by recent mutations, populations that have been of constant size, such as the Saami, may be much better suited to map genes for complex traits that are caused by older mutations. PMID:9398845

Laan, M; Pääbo, S

1997-12-01

8

Demographic history and rare allele sharing among human populations.  

PubMed

High-throughput sequencing technology enables population-level surveys of human genomic variation. Here, we examine the joint allele frequency distributions across continental human populations and present an approach for combining complementary aspects of whole-genome, low-coverage data and targeted high-coverage data. We apply this approach to data generated by the pilot phase of the Thousand Genomes Project, including whole-genome 2-4× coverage data for 179 samples from HapMap European, Asian, and African panels as well as high-coverage target sequencing of the exons of 800 genes from 697 individuals in seven populations. We use the site frequency spectra obtained from these data to infer demographic parameters for an Out-of-Africa model for populations of African, European, and Asian descent and to predict, by a jackknife-based approach, the amount of genetic diversity that will be discovered as sample sizes are increased. We predict that the number of discovered nonsynonymous coding variants will reach 100,000 in each population after ?1,000 sequenced chromosomes per population, whereas ?2,500 chromosomes will be needed for the same number of synonymous variants. Beyond this point, the number of segregating sites in the European and Asian panel populations is expected to overcome that of the African panel because of faster recent population growth. Overall, we find that the majority of human genomic variable sites are rare and exhibit little sharing among diverged populations. Our results emphasize that replication of disease association for specific rare genetic variants across diverged populations must overcome both reduced statistical power because of rarity and higher population divergence. PMID:21730125

Gravel, Simon; Henn, Brenna M; Gutenkunst, Ryan N; Indap, Amit R; Marth, Gabor T; Clark, Andrew G; Yu, Fuli; Gibbs, Richard A; Bustamante, Carlos D

2011-07-19

9

Demographic history and rare allele sharing among human populations  

PubMed Central

High-throughput sequencing technology enables population-level surveys of human genomic variation. Here, we examine the joint allele frequency distributions across continental human populations and present an approach for combining complementary aspects of whole-genome, low-coverage data and targeted high-coverage data. We apply this approach to data generated by the pilot phase of the Thousand Genomes Project, including whole-genome 2–4× coverage data for 179 samples from HapMap European, Asian, and African panels as well as high-coverage target sequencing of the exons of 800 genes from 697 individuals in seven populations. We use the site frequency spectra obtained from these data to infer demographic parameters for an Out-of-Africa model for populations of African, European, and Asian descent and to predict, by a jackknife-based approach, the amount of genetic diversity that will be discovered as sample sizes are increased. We predict that the number of discovered nonsynonymous coding variants will reach 100,000 in each population after ?1,000 sequenced chromosomes per population, whereas ?2,500 chromosomes will be needed for the same number of synonymous variants. Beyond this point, the number of segregating sites in the European and Asian panel populations is expected to overcome that of the African panel because of faster recent population growth. Overall, we find that the majority of human genomic variable sites are rare and exhibit little sharing among diverged populations. Our results emphasize that replication of disease association for specific rare genetic variants across diverged populations must overcome both reduced statistical power because of rarity and higher population divergence.

Gravel, Simon; Henn, Brenna M.; Gutenkunst, Ryan N.; Indap, Amit R.; Marth, Gabor T.; Clark, Andrew G.; Yu, Fuli; Gibbs, Richard A.; Bustamante, Carlos D.; Altshuler, David L.; Durbin, Richard M.; Abecasis, Goncalo R.; Bentley, David R.; Chakravarti, Aravinda; Clark, Andrew G.; Collins, Francis S.; De La Vega, Francisco M.; Donnelly, Peter; Egholm, Michael; Flicek, Paul; Gabriel, Stacey B.; Gibbs, Richard A.; Knoppers, Bartha M.; Lander, Eric S.; Lehrach, Hans; Mardis, Elaine R.; McVean, Gil A.; Nickerson, Debbie A.; Peltonen, Leena; Schafer, Alan J.; Sherry, Stephen T.; Wang, Jun; Wilson, Richard K.; Gibbs, Richard A.; Deiros, David; Metzker, Mike; Muzny, Donna; Reid, Jeff; Wheeler, David; Wang, Jun; Li, Jingxiang; Jian, Min; Li, Guoqing; Li, Ruiqiang; Liang, Huiqing; Tian, Geng; Wang, Bo; Wang, Jian; Wang, Wei; Yang, Huanming; Zhang, Xiuqing; Zheng, Huisong; Lander, Eric S.; Altshuler, David L.; Ambrogio, Lauren; Bloom, Toby; Cibulskis, Kristian; Fennell, Tim J.; Gabriel, Stacey B.; Jaffe, David B.; Shefler, Erica; Sougnez, Carrie L.; Bentley, David R.; Gormley, Niall; Humphray, Sean; Kingsbury, Zoya; Koko-Gonzales, Paula; Stone, Jennifer; McKernan, Kevin J.; Costa, Gina L.; Ichikawa, Jeffry K.; Lee, Clarence C.; Sudbrak, Ralf; Lehrach, Hans; Borodina, Tatiana A.; Dahl, Andreas; Davydov, Alexey N.; Marquardt, Peter; Mertes, Florian; Nietfeld, Wilfiried; Rosenstiel, Philip; Schreiber, Stefan; Soldatov, Aleksey V.; Timmermann, Bernd; Tolzmann, Marius; Egholm, Michael; Affourtit, Jason; Ashworth, Dana; Attiya, Said; Bachorski, Melissa; Buglione, Eli; Burke, Adam; Caprio, Amanda; Celone, Christopher; Clark, Shauna; Conners, David; Desany, Brian; Gu, Lisa; Guccione, Lorri; Kao, Kalvin; Kebbel, Andrew; Knowlton, Jennifer; Labrecque, Matthew; McDade, Louise; Mealmaker, Craig; Minderman, Melissa; Nawrocki, Anne; Niazi, Faheem; Pareja, Kristen; Ramenani, Ravi; Riches, David; Song, Wanmin; Turcotte, Cynthia; Wang, Shally; Mardis, Elaine R.; Wilson, Richard K.; Dooling, David; Fulton, Lucinda; Fulton, Robert; Weinstock, George; Durbin, Richard M.; Burton, John; Carter, David M.; Churcher, Carol; Coffey, Alison; Cox, Anthony; Palotie, Aarno; Quail, Michael; Skelly, Tom; Stalker, James; Swerdlow, Harold P.; Turner, Daniel; De Witte, Anniek; Giles, Shane; Gibbs, Richard A.; Wheeler, David; Bainbridge, Matthew; Challis, Danny; Sabo, Aniko; Yu, Fuli; Yu, Jin; Wang, Jun; Fang, Xiaodong; Guo, Xiaosen; Li, Ruiqiang; Li, Yingrui; Luo, Ruibang; Tai, Shuaishuai; Wu, Honglong; Zheng, Hancheng; Zheng, Xiaole; Zhou, Yan; Li, Guoqing; Wang, Jian; Yang, Huanming; Marth, Gabor T.; Garrison, Erik P.; Huang, Weichun; Indap, Amit; Kural, Deniz; Lee, Wan-Ping; Leong, Wen Fung; Quinlan, Aaron R.; Stewart, Chip; Stromberg, Michael P.; Ward, Alistair N.; Wu, Jiantao; Lee, Charles; Mills, Ryan E.; Shi, Xinghua; Daly, Mark J.; DePristo, Mark A.; Altshuler, David L.; Ball, Aaron D.; Banks, Eric; Bloom, Toby; Browning, Brian L.; Cibulskis, Kristian; Fennell, Tim J.; Garimella, Kiran V.; Grossman, Sharon R.; Handsaker, Robert E.; Hanna, Matt; Hartl, Chris; Jaffe, David B.; Kernytsky, Andrew M.; Korn, Joshua M.; Li, Heng; Maguire, Jared R.; McCarroll, Steven A.; McKenna, Aaron; Nemesh, James C.; Philippakis, Anthony A.; Poplin, Ryan E.; Price, Alkes; Rivas, Manuel A.; Sabeti, Pardis C.; Schaffner, Stephen F.; Shefler, Erica; Shlyakhter, Ilya A.; Cooper, David N.; Ball, Edward V.; Mort, Matthew; Phillips, Andrew D.; Stenson, Peter D.; Sebat, Jonathan; Makarov, Vladimir; Ye, Kenny; Yoon, Seungtai C.; Bustamante, Carlos D.; Clark, Andrew G.; Boyko, Adam; Degenhardt, Jeremiah; Gravel, Simon; Gutenkunst, Ryan N.; Kaganovich, Mark; Keinan, Alon; Lacroute, Phil; Ma, Xin; Reynolds, Andy; Clarke, Laura; Flicek, Paul; Cunningham, Fiona; Herrero, Javier; Keenen, Stephen; Kulesha, Eugene; Leinonen, Rasko; McLaren, William M.; Radhakrishnan, Rajesh; Smith, Richard E.; Zalunin, Vadim; Zheng-Bradley, Xiangqun; Korbel, Jan O.; Stutz, Adrian M.; Humphray, Sean; Bauer, Markus; Cheetham, R. Keira; Cox, Tony; Eberle, Michael; James, Terena; Kahn, Scott; Murray, Lisa; Chakravarti, Aravinda; Ye, Kai; De La Vega, Francisco M.; Fu, Yutao; Hyland, Fiona C. L.; Manning, Jonathan M.; McLaughlin, Stephen F.; Peckham, Heather E.; Sakarya, Onur; Sun, Yongming A.; Tsung, Eric F.; Batzer, Mark A.; Konkel, Miriam K.; Walker, Jerilyn A.; Sudbrak, Ralf; Albrecht, Marcus W.; Amstislavskiy, Vyacheslav S.; Herwig, Ralf; Parkhomchuk, Dimitri V.; Sherry, Stephen T.; Agarwala, Richa; Khouri, Hoda M.; Morgulis, Aleksandr O.; Paschall, Justin E.; Phan, Lon D.; Rotmistrovsky, Kirill E.; Sanders, Robert D.; Shumway, Martin F.

2011-01-01

10

Joint Genome Institute's Automation Approach and History  

SciTech Connect

Department of Energy/Joint Genome Institute (DOE/JGI) collaborates with DOE national laboratories and community users, to advance genome science in support of the DOE missions of clean bio-energy, carbon cycling, and bioremediation.

Roberts, Simon

2006-07-05

11

Inferring the demographic history of European Ficedula flycatcher populations  

PubMed Central

Background Inference of population and species histories and population stratification using genetic data is important for discriminating between different speciation scenarios and for correct interpretation of genome scans for signs of adaptive evolution and trait association. Here we use data from 24 intronic loci re-sequenced in population samples of two closely related species, the pied flycatcher and the collared flycatcher. Results We applied Isolation-Migration models, assignment analyses and estimated the genetic differentiation and diversity between species and between populations within species. The data indicate a divergence time between the species of <1 million years, significantly shorter than previous estimates using mtDNA, point to a scenario with unidirectional gene-flow from the pied flycatcher into the collared flycatcher and imply that barriers to hybridisation are still permeable in a recently established hybrid zone. Furthermore, we detect significant population stratification, predominantly between the Spanish population and other pied flycatcher populations. Conclusions Our results provide further evidence for a divergence process where different genomic regions may be at different stages of speciation. We also conclude that forthcoming analyses of genotype-phenotype relations in these ecological model species should be designed to take population stratification into account.

2013-01-01

12

Demographic Histories, Isolation and Social Factors as Determinants of the Genetic Structure of Alpine Linguistic Groups  

PubMed Central

Great European mountain ranges have acted as barriers to gene flow for resident populations since prehistory and have offered a place for the settlement of small, and sometimes culturally diverse, communities. Therefore, the human groups that have settled in these areas are worth exploring as an important potential source of diversity in the genetic structure of European populations. In this study, we present new high resolution data concerning Y chromosomal variation in three distinct Alpine ethno-linguistic groups, Italian, Ladin and German. Combining unpublished and literature data on Y chromosome and mitochondrial variation, we were able to detect different genetic patterns. In fact, within and among population diversity values observed vary across linguistic groups, with German and Italian speakers at the two extremes, and seem to reflect their different demographic histories. Using simulations we inferred that the joint effect of continued genetic isolation and reduced founding group size may explain the apportionment of genetic diversity observed in all groups. Extending the analysis to other continental populations, we observed that the genetic differentiation of Ladins and German speakers from Europeans is comparable or even greater to that observed for well known outliers like Sardinian and Basques. Finally, we found that in south Tyroleans, the social practice of Geschlossener Hof, a hereditary norm which might have favored male dispersal, coincides with a significant intra-group diversity for mtDNA but not for Y chromosome, a genetic pattern which is opposite to those expected among patrilocal populations. Together with previous evidence regarding the possible effects of “local ethnicity” on the genetic structure of German speakers that have settled in the eastern Italian Alps, this finding suggests that taking socio-cultural factors into account together with geographical variables and linguistic diversity may help unveil some yet to be understood aspects of the genetic structure of European populations.

Coia, Valentina; Capocasa, Marco; Anagnostou, Paolo; Pascali, Vincenzo; Scarnicci, Francesca; Boschi, Ilaria; Battaggia, Cinzia; Crivellaro, Federica; Ferri, Gianmarco; Alu, Milena; Brisighelli, Francesca; Busby, George B. J.; Capelli, Cristian; Maixner, Frank; Cipollini, Giovanna; Viazzo, Pier Paolo; Zink, Albert; Destro Bisol, Giovanni

2013-01-01

13

Psychosocial Risk Factors for Upper Respiratory Infection: Demographic and Health History Predictors of URI (Upper Respiratory Illness) During Basic Training.  

National Technical Information Service (NTIS)

Health history and demographic attributes have been suggested as predictors of susceptibility to upper respiratory infections in basic training. This study attempted to replicate evidence that being white, less educated, and having past history of frequen...

L. K. Hervig R. R. Vickers

1988-01-01

14

Unification Theory of Optimal Life Histories and Linear Demographic Models in Internal Stochasticity  

PubMed Central

Life history of organisms is exposed to uncertainty generated by internal and external stochasticities. Internal stochasticity is generated by the randomness in each individual life history, such as randomness in food intake, genetic character and size growth rate, whereas external stochasticity is due to the environment. For instance, it is known that the external stochasticity tends to affect population growth rate negatively. It has been shown in a recent theoretical study using path-integral formulation in structured linear demographic models that internal stochasticity can affect population growth rate positively or negatively. However, internal stochasticity has not been the main subject of researches. Taking account of effect of internal stochasticity on the population growth rate, the fittest organism has the optimal control of life history affected by the stochasticity in the habitat. The study of this control is known as the optimal life schedule problems. In order to analyze the optimal control under internal stochasticity, we need to make use of “Stochastic Control Theory” in the optimal life schedule problem. There is, however, no such kind of theory unifying optimal life history and internal stochasticity. This study focuses on an extension of optimal life schedule problems to unify control theory of internal stochasticity into linear demographic models. First, we show the relationship between the general age-states linear demographic models and the stochastic control theory via several mathematical formulations, such as path–integral, integral equation, and transition matrix. Secondly, we apply our theory to a two-resource utilization model for two different breeding systems: semelparity and iteroparity. Finally, we show that the diversity of resources is important for species in a case. Our study shows that this unification theory can address risk hedges of life history in general age-states linear demographic models.

Oizumi, Ryo

2014-01-01

15

Multilocus dataset reveals demographic histories of two peat mosses in Europe  

PubMed Central

Background Revealing the past and present demographic history of populations is of high importance to evaluate the conservation status of species. Demographic data can be obtained by direct monitoring or by analysing data of historical and recent collections. Although these methods provide the most detailed information they are very time consuming. Another alternative way is to make use of the information accumulated in the species' DNA over its history. Recent development of the coalescent theory makes it possible to reconstruct the demographic history of species using nucleotide polymorphism data. To separate the effect of natural selection and demography, multilocus analysis is needed because these two forces can produce similar patterns of polymorphisms. In this study we investigated the amount and pattern of sequence variability of a Europe wide sample set of two peat moss species (Sphagnum fimbriatum and S. squarrosum) with similar distributions and mating systems but presumably contrasting historical demographies using 3 regions of the nuclear genome (appr. 3000 bps). We aimed to draw inferences concerning demographic, and phylogeographic histories of the species. Results All three nuclear regions supported the presence of an Atlantic and Non-Atlantic clade of S. fimbriatum suggesting glacial survival of the species along the Atlantic coast of Europe. Contrarily, S. squarrosum haplotypes showed three clades but no geographic structure at all. Maximum likelihood, mismatch and Bayesian analyses supported a severe historical bottleneck and a relatively recent demographic expansion of the Non-Atlantic clade of S. fimbriatum, whereas size of S. squarrosum populations has probably decreased in the past. Species wide molecular diversity of the two species was nearly the same with an excess of replacement mutations in S. fimbriatum. Similar levels of molecular diversity, contrasting phylogeographic patterns and excess of replacement mutations in S. fimbriatum compared to S. squarrosum mirror unexpected differences in the demography and population history of the species. Conclusion This study represents the first detailed European wide phylodemographic investigation on bryophytes and shows how pattern of nucleotide polymorphism can reveal unexpected differences in the population history of haploid plants with seemingly similar characteristics.

Szovenyi, Peter; Hock, Zsofia; Schneller, Jakob J; Toth, Zoltan

2007-01-01

16

Demographic History Has Influenced Nucleotide Diversity in European Pinus sylvestris Populations  

PubMed Central

To infer the role of natural selection in shaping standing genetic diversity, it is necessary to assess the genomewide impact of demographic history on nucleotide diversity. In this study we analyzed sequence diversity of 16 nuclear loci in eight Pinus sylvestris populations. Populations were divided into four geographical groups on the basis of their current location and the geographical history of the region: northern Europe, central Europe, Spain, and Turkey. There were no among-group differences in the level of silent nucleotide diversity, which was ?0.005/bp in all groups. There was some evidence that linkage disequilibrium extended further in northern Europe than in central Europe: the estimates of the population recombination rate parameter, ?, were 0.0064 and 0.0294, respectively. The summary statistics of nucleotide diversity in central and northern European populations were compatible with an ancient bottleneck rather than the standard neutral model.

Pyhajarvi, Tanja; Garcia-Gil, M. Rosario; Knurr, Timo; Mikkonen, Merja; Wachowiak, Witold; Savolainen, Outi

2007-01-01

17

Genetic diversification and demographic history of the cactophilic pseudoscorpion Dinocheirus arizonensis from the Sonoran Desert  

PubMed Central

Sequence data from a segment of the mitochondrial cytochrome c oxidase subunit I (COI) gene were used to examine phylogenetic relationships, estimate gene flow and infer demographic history of the cactophilic chernetid pseudoscorpion, Dinocheirus arizonensis (Banks, 1901), from the Sonoran Desert. Phylogenetic trees resolved two clades of D. arizonensis, one from mainland Sonora, Mexico and southern Arizona (clade I) and the other from the Baja California peninsula and southern Arizona (clade II). The two clades were separated by a mean genetic distance (d) of ~2.6%. Hierarchical analysis of molecular variance indicated highly significant population structuring in D. arizonensis (overall ?ST = 0.860; P < 0.0001), with 80% of the genetic variation distributed among the two clades. Most pairwise comparisons of ?ST among populations within each clade, however, were not significant. The results suggest that phoretic dispersal on vagile cactophilic insects such as the neriid cactus fly Odontoloxozus longicornis (Coquillett, 1904) provides sufficient gene flow to offset the accumulation of unique haplotypes within each clade of the non-vagile pseudoscorpion. Preliminary results on dispersal capability of O. longicornis were consistent with this conclusion. Tests designed to reconstruct demographic history from sequence data indicated that both clades of D. arizonensis, as well as O. longicornis, have experienced historical population expansions. Potential barriers to gene flow that may have led to genetic isolation and diversification in clades I and II of Dinocheirus arizonensis are discussed.

Pfeiler, Edward; Bitler, Ben G.; Castrezana, Sergio; Matzkin, Luciano M.; Markow, Therese A.

2009-01-01

18

When History moves on: The Foundations and Diffusion of a Second Demographic Transition  

Microsoft Academic Search

The paper discusses the contrasts between a first (FDT) and a second demographic transition (SDT) in terms of their respective demographic, structural and cultural dimensions. In this section we show that the \\

Ron Lesthaeghe; Johan Surkyn

19

Comparative Genetic Structure and Demographic History in Endemic Gal?pagos Weevils  

PubMed Central

The challenge of maintaining genetic diversity within populations can be exacerbated for island endemics if they display population dynamics and behavioral attributes that expose them to genetic drift without the benefits of gene flow. We assess patterns of the genetic structure and demographic history in 27 populations of 9 species of flightless endemic Galápagos weevils from 9 of the islands and 1 winged introduced close relative. Analysis of mitochondrial DNA reveals a significant population structure and moderately variable, though demographically stable, populations for lowland endemics (FST = 0.094–0.541; ?: 0.014–0.042; Mismatch P = 0.003–0.026; and D(Tajima) = ?0.601 to 1.203), in contrast to signals of past contractions and expansions in highland specialists on 2 islands (Mismatch P = 0.003–0.026 and D(Tajima) = ?0.601 to 1.203). We interpret this series of variable and highly structured population groups as a system of long-established, independently founded island units, where structuring could be a signal of microallopatric differentiation due to patchy host plant distribution and poor dispersal abilities. We suggest that the severe reduction and subsequent increase of a suitably moist habitat that accompanied past climatic variation could have contributed to the observed population fluctuations in highland specialists. We propose the future exploration of hybridization between the introduced and highland endemic species on Santa Cruz, especially given the expansion of the introduced species into the highlands, the sensitivity to past climatic variation detected in highland populations, and the potentially threatened state of single-island endemics.

Stepien, Courtney C.; Sijapati, Manisha; Roque Albelo, Lazaro

2012-01-01

20

Population Genetic Structure and Demographic History of Atrina pectinata Based on Mitochondrial DNA and Microsatellite Markers  

PubMed Central

The pen shell, Atrina pectinata, is one of the commercial bivalves in East Asia and thought to be recently affected by anthropogenic pressure (habitat destruction and/or fishing pressure). Information on its population genetic structure is crucial for the conservation of A. pectinata. Considering its long pelagic larval duration and iteroparity with high fecundity, the genetic structure for A. pectinata could be expected to be weak at a fine scale. However, the unusual oceanography in the coasts of China and Korea suggests potential for restricted dispersal of pelagic larvae and geographical differentiation. In addition, environmental changes associated with Pleistocene sea level fluctuations on the East China Sea continental shelf may also have strongly influenced historical population demography and genetic diversity of marine organisms. Here, partial sequences of the mitochondrial Cytochrome c oxidase subunit I (COI) gene and seven microsatellite loci were used to estimate population genetic structure and demographic history of seven samples from Northern China coast and one sample from North Korea coast. Despite high levels of genetic diversity within samples, there was no genetic differentiation among samples from Northern China coast and low but significant genetic differentiation between some of the Chinese samples and the North Korean sample. A late Pleistocene population expansion, probably after the Last Glacial Maximum, was also demonstrated for A. pectinata samples. No recent genetic bottleneck was detected in any of the eight samples. We concluded that both historical recolonization (through population range expansion and demographic expansion in the late Pleistocene) and current gene flow (through larval dispersal) were responsible for the weak level of genetic structure detected in A. pectinata.

Xue, Dong-Xiu; Wang, Hai-Yan; Zhang, Tao; Liu, Jin-Xian

2014-01-01

21

Demographic and environmental influences on life-history traits of isolated populations of the Andean catfish Astroblepus ubidiai  

Microsoft Academic Search

In this study, we examined the influence of demographic and environmental variables on the life histories of six remnant populations of the Andean catfishAstroblepus ubidiai (Actinopterygii; Siluriform) located in isolated refuges, and tested six predictions on the relationships between age at maturity, generation time, population density and juvenile and adult growth and survival rates. The three populations inhabiting the watershed

Luis A. Vélez-Espino; Michael G. Fox

2005-01-01

22

Diversification, Biogeographic Pattern, and Demographic History of Taiwanese Scutellaria Species Inferred from Nuclear and Chloroplast DNA  

PubMed Central

The ragged topography created by orogenesis generates diversified habitats for plants in Taiwan. In addition to colonization from nearby mainland China, high species diversity and endemism of plants is also present in Taiwan. Five of the seven Scutellaria species (Lamiaceae) in Taiwan, for example, are endemic to the island. Hypotheses of multiple sources or in situ radiation have arisen to explain the high endemism of Taiwanese species. In this study, phylogenetic analyses using both nuclear and chloroplast markers revealed the multiple sources of Taiwanese Scutellaria species and confirmed the rapid and recent speciation of endemic species, especially those of the “indica group” composed of S. indica, S. austrotaiwanensis, S. tashiroi, and S. playfairii. The common ancestors of the indica group colonized first in northern Taiwan and dispersed regionally southward and eastward. Climate changes during glacial/interglacial cycles led to gradual colonization and variance events in the ancestors of these species, resulting in the present distribution and genetic differentiation of extant populations. Population decline was also detected in S. indica, which might reflect a bottleneck effect from the glacials. In contrast, the recently speciated endemic members of the indica group have not had enough time to accumulate much genetic variation and are thus genetically insensitive to demographic fluctuations, but the extant lineages were spatially expanded in the coalescent process. This study integrated phylogenetic and population genetic analyses to illustrate the evolutionary history of Taiwanese Scutellaria of high endemism and may be indicative of the diversification mechanism of plants on continental islands.

Liao, Pei-Chun

2012-01-01

23

Effect of Population Reduction on mtDNA Diversity and Demographic History of Korean Cattle Populations  

PubMed Central

The population sizes of three Korean indigenous cattle populations have been drastically reduced over the past decades. In this study, we examined the extent to which reduction in populations influenced genetic diversity, population structure and demographic history using complete mitochondrial DNA (mtDNA) control region sequences. The complete mtDNA control region was sequenced in 56 individuals from Korean Black (KB), Jeju Black (JEB) and Korean Brindle (BRI) cattle populations. We included 27 mtDNA sequences of Korean Brown (BRO) from the GenBank database. Haplotype diversity estimate for the total population was high (0.870) while nucleotide diversity was low (0.004). The KB showed considerably low nucleotide (? = 0.001) and haplotype (h = 0.368) diversities. Analysis of molecular variance revealed a low level of genetic differentiation but this was highly significant (p<0.001) among the cattle populations. Of the total genetic diversity, 7.6% was attributable to among cattle populations diversity and the rest (92.4%) to differences within populations. The mismatch distribution analysis and neutrality tests revealed that KB population was in genetic equilibrium or decline. Indeed, unless an appropriate breeding management practice is developed, inbreeding and genetic drift will further impoverish genetic diversity of these cattle populations. Rational breed development and conservation strategy is needed to safeguard these cattle population.

Dadi, Hailu; Lee, Seung-Hwan; Jung, Kyoung Sup; Choi, Jae Won; Ko, Moon-Suck; Han, Young-Joon; Kim, Jong-Joo; Kim, Kwan-Suk

2012-01-01

24

Demographic history of a recent invasion of house mice on the isolated Island of Gough.  

PubMed

Island populations provide natural laboratories for studying key contributors to evolutionary change, including natural selection, population size and the colonization of new environments. The demographic histories of island populations can be reconstructed from patterns of genetic diversity. House mice (Mus musculus) inhabit islands throughout the globe, making them an attractive system for studying island colonization from a genetic perspective. Gough Island, in the central South Atlantic Ocean, is one of the remotest islands in the world. House mice were introduced to Gough Island by sealers during the 19th century and display unusual phenotypes, including exceptionally large body size and carnivorous feeding behaviour. We describe genetic variation in Gough Island mice using mitochondrial sequences, nuclear sequences and microsatellites. Phylogenetic analysis of mitochondrial sequences suggested that Gough Island mice belong to Mus musculus domesticus, with the maternal lineage possibly originating in England or France. Cluster analyses of microsatellites revealed genetic membership for Gough Island mice in multiple coastal populations in Western Europe, suggesting admixed ancestry. Gough Island mice showed substantial reductions in mitochondrial and nuclear sequence variation and weak reductions in microsatellite diversity compared with Western European populations, consistent with a population bottleneck. Approximate Bayesian computation (ABC) estimated that mice recently colonized Gough Island (~100 years ago) and experienced a 98% reduction in population size followed by a rapid expansion. Our results indicate that the unusual phenotypes of Gough Island mice evolved rapidly, positioning these mice as useful models for understanding rapid phenotypic evolution. PMID:24617968

Gray, Melissa M; Wegmann, Daniel; Haasl, Ryan J; White, Michael A; Gabriel, Sofia I; Searle, Jeremy B; Cuthbert, Richard J; Ryan, Peter G; Payseur, Bret A

2014-04-01

25

Comparative phylogeography and demographic history of the wood lemming (Myopus schisticolor): implications for late Quaternary history of the taiga species in Eurasia  

Microsoft Academic Search

The association between demographic history, genealogy and geographical distribution of mitochondrial DNA cytochrome b haplotypes was studied in the wood lemming (Myopus schisticolor), a species that is closely associated with the boreal forest of the Eurasian taiga zone from Scandinavia to the Pacific coast. Except for a major phylogeographic discontinuity (0.9% nucleotide divergence) in southeastern Siberia, only shallow regional genetic

V. B. FEDOROV; A. V. GOROPASHNA YA; G. G. BOESKOROV; J. A. COOK

2008-01-01

26

Complex population genetic and demographic history of the Salangid, Neosalanx taihuensis, based on cytochrome b sequences  

PubMed Central

Background The Salangid icefish Neosalanx taihuensis (Salangidae) is an economically important fish, which is endemic to China, restricted to large freshwater systems (e.g. lakes, large rivers and estuaries) and typically exhibit low vagility. The continuous distribution ranges from the temperate region of the Huai and Yellow River basins to the subtropical region of the Pearl River basin. This wide ranging distribution makes the species an ideal model for the study of palaeoclimatic effects on population genetic structure and phylogeography. Here, we aim to analyze population genetic differentiation within and between river basins and demographic history in order to understand how this species responded to severe climatic oscillations, decline of the sea levels during the Pleistocene ice ages and tectonic activity. Results We obtained the complete mtDNA cytochrome b sequences (1141 bp) of 354 individuals from 13 populations in the Pearl River, the Yangze River and the Huai River basin. Thirty-six haplotypes were detected. Haplotype frequency distributions were strongly skewed, with most haplotypes (n = 24) represented only in single samples each and thus restricted to a single population. The most common haplotype (H36) was found in 49.15% of all individuals. Analysis of molecular variance (AMOVA) revealed a random pattern in the distribution of genetic diversity, which is inconsistent with contemporary hydrological structure. Significant levels of genetic subdivision were detected among populations within basins rather than between the three basins. Demographic analysis revealed that the population size in the Pearl River basin has remained relatively constant whereas the populations in the Yangze River and the Huai River basins expanded about 221 and 190 kyr ago, respectively, with the majority of mutations occurring after the last glacial maximum (LGM). Conclusion The observed complex genetic pattern of N. taihuensis is coherent with a scenario of multiple unrelated founding events by long-distance colonization and dispersal combined with contiguous population expansion and locally restricted gene flow. We also found that this species was likely severely impacted by past glaciations. More favourable climate and the formation of large suitable habitations together facilitated population expansion after the late Quaternary (especially the LGM). We proposed that all populations should be managed and conserved separately, especially for habitat protection.

2008-01-01

27

Evaluation of demographic history and neutral parameterization on the performance of FST outlier tests.  

PubMed

FST outlier tests are a potentially powerful way to detect genetic loci under spatially divergent selection. Unfortunately, the extent to which these tests are robust to nonequilibrium demographic histories has been understudied. We developed a landscape genetics simulator to test the effects of isolation by distance (IBD) and range expansion on FST outlier methods. We evaluated the two most commonly used methods for the identification of FST outliers (FDIST2 and BayeScan, which assume samples are evolutionarily independent) and two recent methods (FLK and Bayenv2, which estimate and account for evolutionary nonindependence). Parameterization with a set of neutral loci ('neutral parameterization') always improved the performance of FLK and Bayenv2, while neutral parameterization caused FDIST2 to actually perform worse in the cases of IBD or range expansion. BayeScan was improved when the prior odds on neutrality was increased, regardless of the true odds in the data. On their best performance, however, the widely used methods had high false-positive rates for IBD and range expansion and were outperformed by methods that accounted for evolutionary nonindependence. In addition, default settings in FDIST2 and BayeScan resulted in many false positives suggesting balancing selection. However, all methods did very well if a large set of neutral loci is available to create empirical P-values. We conclude that in species that exhibit IBD or have undergone range expansion, many of the published FST outliers based on FDIST2 and BayeScan are probably false positives, but FLK and Bayenv2 show great promise for accurately identifying loci under spatially divergent selection. PMID:24655127

Lotterhos, Katie E; Whitlock, Michael C

2014-05-01

28

The demographic history of populations experiencing asymmetric gene flow: combining simulated and empirical data.  

PubMed

Population structure can significantly affect genetic-based demographic inferences, generating spurious bottleneck-like signals. Previous studies have typically assumed island or stepping-stone models, which are characterized by symmetric gene flow. However, many organisms are characterized by asymmetric gene flow. Here, we combined simulated and empirical data to test whether asymmetric gene flow affects the inference of past demographic changes. Through the analysis of simulated genetic data with three methods (i.e. bottleneck, M-ratio and msvar), we demonstrated that asymmetric gene flow biases past demographic changes. Most biases were towards spurious signals of expansion, albeit their strength depended on values of effective population size and migration rate. It is noteworthy that the spurious signals of demographic changes also depended on the statistical approach underlying each of the three methods. For one of the three methods, biases induced by asymmetric gene flow were confirmed in an empirical multispecific data set involving four freshwater fish species (Squalius cephalus, Leuciscus burdigalensis, Gobio gobio and Phoxinus phoxinus). However, for the two other methods, strong signals of bottlenecks were detected for all species and across two rivers. This suggests that, although potentially biased by asymmetric gene flow, some of these methods were able to bypass this bias when a bottleneck actually occurred. Our results show that population structure and dispersal patterns have to be considered for proper inference of demographic changes from genetic data. PMID:23718226

Paz-Vinas, I; Quéméré, E; Chikhi, L; Loot, G; Blanchet, S

2013-06-01

29

A survey of temporomandibular joint dislocation: aetiology, demographics, risk factors and management in 96 Nigerian cases  

Microsoft Academic Search

A retrospective study of 96 cases of temporomandibular joint dislocation was undertaken. Patients’ ages ranged from 9 to 85 years (mean±SD, 35.3±17.4 years) and peak incidence was at 20–29 years. Mean duration was 7.9 weeks (range, 1h to 3 years). Acute, chronic and recurrent dislocations were seen in 46 (47.9%), 29 (30.2%) and 21 (21.9%) patients, respectively. Males dominated in

V. I. Ugboko; F. O. Oginni; S. O. Ajike; H. O. Olasoji; E. T. Adebayo

2005-01-01

30

Joint motion pattern classification by cluster analysis of kinematic, demographic, and subjective variables.  

PubMed

The purpose of this study is to identify joint motion patterns by classifying the full range of motion (ROM) into several sections. Forty participants were stratified by age and gender and they performed 18 full-swing motions at a self-selected speed. Joint angle, angular velocity, angular acceleration, and subjective discomfort rating were collected for each motion. K-means cluster analyses were used to classify joint motion patterns and ROM sections. The results showed that two or three clusters were mainly determined by the kinematic variables of angular velocity and acceleration. The motions of three clusters showed that the ROM sections of low and moderate velocity with moderate and high accelerations occurred in the initial (negative) and terminal (positive) phases, respectively, whereas those of high velocity with low acceleration were shown in the mid (neutral) phase. The motions of two clusters revealed that while the patterns of high velocity and high acceleration were found on the positive side of the ROM, those of low velocity and low acceleration were on the negative and neutral sides. The ROM sections close to both ends of the ROM may have a larger physical load than the others. This study provides information that could be useful for developing postural analysis tools for dynamic work. PMID:23347907

Hwang, Jaejin; Shin, Hyunjung; Jung, Myung-Chul

2013-07-01

31

Population structure and demographic history of a tropical lowland rainforest tree species Shorea parvifolia (Dipterocarpaceae) from Southeastern Asia.  

PubMed

Distribution of tropical rainforests in Southeastern Asia has changed over geo-logical time scale, due to movement of tectonic plates and/or global climatic changes. Shorea parvifolia is one of the most common tropical lowland rainforest tree species in Southeastern Asia. To infer population structure and demographic history of S. parvifolia, as indicators of temporal changes in the distribution and extent of tropical rainforest in this region, we studied levels and patterns of nucleotide polymorphism in the following five nuclear gene regions: GapC, GBSSI, PgiC, SBE2, and SODH. Seven populations from peninsular Malaysia, Sumatra, and eastern Borneo were included in the analyses. STRUCTURE analysis revealed that the investigated populations are divided into two groups: Sumatra-Malay and Borneo. Furthermore, each group contained one admixed population. Under isolation with migration model, divergence of the two groups was estimated to occur between late Pliocene (2.6 MYA) and middle Pleistocene (0.7 MYA). The log-likelihood ratio tests of several demographic models strongly supported model with population expansion and low level of migration after divergence of the Sumatra-Malay and Borneo groups. The inferred demographic history of S. parvifolia suggested the presence of a scarcely forested land bridge on the Sunda Shelf during glacial periods in the Pleistocene and predominance of tropical lowland rainforest at least in Sumatra and eastern Borneo. PMID:22957170

Iwanaga, Hiroko; Teshima, Kosuke M; Khatab, Ismael A; Inomata, Nobuyuki; Finkeldey, Reiner; Siregar, Iskandar Z; Siregar, Ulfah J; Szmidt, Alfred E

2012-07-01

32

Population structure and demographic history of a tropical lowland rainforest tree species Shorea parvifolia (Dipterocarpaceae) from Southeastern Asia  

PubMed Central

Distribution of tropical rainforests in Southeastern Asia has changed over geo-logical time scale, due to movement of tectonic plates and/or global climatic changes. Shorea parvifolia is one of the most common tropical lowland rainforest tree species in Southeastern Asia. To infer population structure and demographic history of S. parvifolia, as indicators of temporal changes in the distribution and extent of tropical rainforest in this region, we studied levels and patterns of nucleotide polymorphism in the following five nuclear gene regions: GapC, GBSSI, PgiC, SBE2, and SODH. Seven populations from peninsular Malaysia, Sumatra, and eastern Borneo were included in the analyses. STRUCTURE analysis revealed that the investigated populations are divided into two groups: Sumatra-Malay and Borneo. Furthermore, each group contained one admixed population. Under isolation with migration model, divergence of the two groups was estimated to occur between late Pliocene (2.6 MYA) and middle Pleistocene (0.7 MYA). The log-likelihood ratio tests of several demographic models strongly supported model with population expansion and low level of migration after divergence of the Sumatra-Malay and Borneo groups. The inferred demographic history of S. parvifolia suggested the presence of a scarcely forested land bridge on the Sunda Shelf during glacial periods in the Pleistocene and predominance of tropical lowland rainforest at least in Sumatra and eastern Borneo.

Iwanaga, Hiroko; Teshima, Kosuke M; Khatab, Ismael A; Inomata, Nobuyuki; Finkeldey, Reiner; Siregar, Iskandar Z; Siregar, Ulfah J; Szmidt, Alfred E

2012-01-01

33

Lower extremity joint position sense in runners with and without a history of knee overuse injury.  

PubMed

Kinematic and kinetic analyses are routinely implemented to determine if gait differences exist between runners with and without a history of knee injury. Hip and knee kinematic differences have been reported between knee injured and non-injured runners. Yet, there is no consensus on whether these differences are the primary variables contributing to knee injury. Furthermore, there may be additional underlying factors that contribute to the development of injury that cannot be determined by gait analysis. The purpose of this investigation was to determine if joint position sense differences exist in runners with and without a history of knee overuse injury. Sagittal plane knee and hip joint position sense was measured in 13 runners with a history of knee overuse injury and 13 runners with no history of knee overuse injury. Absolute joint position replication error was measured during both a weight bearing and a non-weight bearing condition. Joint position replication errors at each joint were compared among groups and task using a two-way ANOVA with joint task as the repeated measure. Knee and hip joint replication errors were similar between both groups. The weight bearing and non-weight bearing tasks resulted in similar joint position replication errors. There were no interaction effects. In conclusion, knee flexion and hip adduction joint position sense is similar in runners with and without a history of knee overuse injury. Therefore, joint position sense measured via weight bearing and non-weight bearing joint position replication tasks may not play an important role in the development of knee overuse injury. PMID:22698704

Foch, Eric; Milner, Clare E

2012-07-01

34

Demographic variations in HIV testing history among emergency department patients: implications for HIV screening in US emergency departments  

PubMed Central

Objective To determine the proportion of emergency department (ED) patients who have been tested for human immunodeficiency virus (HIV) infection and assess if patient history of HIV testing varies according to patient demographic characteristics. Design From July 2005–July 2006, a random sample of 18–55-year-old English-speaking patients being treated for sub-critical injury or illness at a northeastern US ED were interviewed on their history of HIV testing. Logistic regression models were created to compare patients by their history of being tested for HIV according to their demography. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated. Results Of 2107 patients surveyed who were not known to be HIV-infected, the median age was 32 years; 54% were male, 71% were white, and 45% were single/never married; 49% had private health-care insurance and 45% had never been tested for HIV. Of the 946 never previously tested for HIV, 56.1% did not consider themselves at risk for HIV. In multivariable logistic regression analyses, those less likely to have been HIV tested were male (OR: 1.32 [1.37–2.73]), white (OR: 1.93 [1.37–2.73]), married (OR: 1.53 [1.12–2.08]), and had private health-care insurance (OR: 2.10 [1.69–2.61]). There was a U-shaped relationship between age and history of being tested for HIV; younger and older patients were less likely to have been tested. History of HIV testing and years of formal education were not related. Conclusion Almost half of ED patients surveyed had never been tested for HIV. Certain demographic groups are being missed though HIV diagnostic testing and screening programmes in other settings. These groups could potentially be reached through universal screening.

Merchant, Roland C; Catanzaro, Bethany M; Seage, George R; Mayer, Kenneth H; Clark, Melissa A; DeGruttola, Victor G; Becker, Bruce M

2011-01-01

35

Genetic structure and demographic history of Colletotrichum gloeosporioides sensu lato and C. truncatum isolates from Trinidad and Mexico  

PubMed Central

Background C. gloeosporioides sensu lato is one of the most economically important post-harvest diseases affecting papaya production worldwide. There is currently no information concerning the genetic structure or demographic history of this pathogen in any of the affected countries. Knowledge of molecular demographic parameters for different populations will improve our understanding of the biogeographic history as well as the evolutionary and adaptive potential of these pathogens. In this study, sequence data for ACT, GPDH, ?-TUB and ITS gene regions were analyzed for C. gloeosporioides sensu lato and C. truncatum isolates infecting papaya in Trinidad and Mexico in order to determine the genetic structure and demographic history of these populations. Results The data indicated that Mexico is the ancestral C. gloeosporioides sensu lato population with asymmetrical migration to Trinidad. Mexico also had the larger effective population size but, both Mexico and Trinidad populations exhibited population expansion. Mexico also had greater nucleotide diversity and high levels of diversity for each gene. There was significant sub-division of the Trinidad and Mexico populations and low levels of genetic divergence among populations for three of the four gene regions; ?-TUB was shown to be under positive selection. There were also dissimilar haplotype characteristics for both populations. Mutation may play a role in shaping the population structure of C. gloeosporioides sensu lato isolates from Trinidad and from Mexico, especially with respect to the ACT and GPDH gene regions. There was no evidence of gene flow between the C. truncatum populations and it is possible that the Mexico and Trinidad populations emerged independently of each other. Conclusions The study revealed relevant information based on the genetic structure as well as the demographic history of two fungal pathogens infecting papaya, C. gloeosporioides sensu lato and C. truncatum, in Trinidad and Mexico. Understanding the genetic structure of pathogen populations will assist in determining the evolutionary potential of the pathogen and in identifying which evolutionary forces may have the greatest impact on durability of resistance. Intervention strategies that target these evolutionary forces would prove to be the most practical.

2013-01-01

36

Covariation in life-history traits, demographics and behaviour in ischnuran damselflies: the evolution of monandry  

Microsoft Academic Search

The apparent erratic variation in life history traits, coloration patterns, and behaviours that exists among species within the damselfly genusIschnurais shown to be interpretable when the species are partitioned into three groups. One group consists of species whose males are missing a pair of stout basal spines on the penultimate segment of their accessory penes. These are the only ischnurans

JAMES V. ROBINSON; RICHARD ALLGEYER

1996-01-01

37

Multilocus coalescent analyses reveal the demographic history and speciation patterns of mouse lemur sister species  

PubMed Central

Background Debate continues as to whether allopatric speciation or peripatric speciation through a founder effect is the predominant force driving evolution in vertebrates. The mouse lemurs of Madagascar are a system in which evolution has generated a large number of species over a relatively recent time frame. Here, we examine speciation patterns in a pair of sister species of mouse lemur, Microcebus murinus and M. griseorufus. These two species have ranges that are disparately proportioned in size, with M. murinus showing a much more extensive range that marginally overlaps that of M. griseorufus. Given that these two species are sister taxa, the asymmetric but overlapping geographic ranges are consistent with a model of peripatric speciation. To test this hypothesis, we analyze DNA sequence data from four molecular markers using coalescent methods. If the peripatric speciation model is supported, we predict substantially greater genetic diversity in M. murinus, relative to M. griseorufus. Further, we expect a larger effective population size in M. murinus and in the common ancestor of the two species than in M. griseorufus, with a concomitant decrease in gene tree/species tree incongruence in the latter and weak signs of demographic expansion in M. murinus. Results Our results reject a model of peripatric divergence. Coalescent effective population size estimates were similar for both extant species and larger than that estimated for their most recent common ancestor. Gene tree results show similar levels of incomplete lineage sorting within species with respect to the species tree, and locus-specific estimates of genetic diversity are concordant for both species. Multilocus demographic analyses suggest range expansions for M. murinus, with this species also experiencing more recent population declines over the past 160 thousand years. Conclusions Results suggest that speciation occurred in allopatry from a common ancestor narrowly distributed throughout southwest Madagascar, with subsequent range expansion for M. murinus. Population decline in M. murinus is likely related to patterns of climate change in Madagascar throughout the Pleistocene, potentially exacerbated by continual anthropogenic perturbation. Genome-level data are needed to quantify the role of niche specialization and adaptation in shaping the current ranges of these species.

2014-01-01

38

Phylogeography and demographic history of Lacerta lepida in the Iberian Peninsula: multiple refugia, range expansions and secondary contact zones  

PubMed Central

Background The Iberian Peninsula is recognized as an important refugial area for species survival and diversification during the climatic cycles of the Quaternary. Recent phylogeographic studies have revealed Iberia as a complex of multiple refugia. However, most of these studies have focused either on species with narrow distributions within the region or species groups that, although widely distributed, generally have a genetic structure that relates to pre-Quaternary cladogenetic events. In this study we undertake a detailed phylogeographic analysis of the lizard species, Lacerta lepida, whose distribution encompasses the entire Iberian Peninsula. We attempt to identify refugial areas, recolonization routes, zones of secondary contact and date demographic events within this species. Results Results support the existence of 6 evolutionary lineages (phylogroups) with a strong association between genetic variation and geography, suggesting a history of allopatric divergence in different refugia. Diversification within phylogroups is concordant with the onset of the Pleistocene climatic oscillations. The southern regions of several phylogroups show a high incidence of ancestral alleles in contrast with high incidence of recently derived alleles in northern regions. All phylogroups show signs of recent demographic and spatial expansions. We have further identified several zones of secondary contact, with divergent mitochondrial haplotypes occurring in narrow zones of sympatry. Conclusions The concordant patterns of spatial and demographic expansions detected within phylogroups, together with the high incidence of ancestral haplotypes in southern regions of several phylogroups, suggests a pattern of contraction of populations into southern refugia during adverse climatic conditions from which subsequent northern expansions occurred. This study supports the emergent pattern of multiple refugia within Iberia but adds to it by identifying a pattern of refugia coincident with the southern distribution limits of individual evolutionary lineages. These areas are important in terms of long-term species persistence and therefore important areas for conservation.

2011-01-01

39

Genetic diversity, genetic structure and demographic history of Cycas simplicipinna (Cycadaceae) assessed by DNA sequences and SSR markers  

PubMed Central

Background Cycas simplicipinna (T. Smitinand) K. Hill. (Cycadaceae) is an endangered species in China. There were seven populations and 118 individuals that we could collect were genotyped in this study. Here, we assessed the genetic diversity, genetic structure and demographic history of this species. Results Analyses of data of DNA sequences (two maternally inherited intergenic spacers of chloroplast, cpDNA and one biparentally inherited internal transcribed spacer region ITS4-ITS5, nrDNA) and sixteen microsatellite loci (SSR) were conducted in the species. Of the 118 samples, 86 individuals from the seven populations were used for DNA sequencing and 115 individuals from six populations were used for the microsatellite study. We found high genetic diversity at the species level, low genetic diversity within each of the seven populations and high genetic differentiation among the populations. There was a clear genetic structure within populations of C. simplicipinna. A demographic history inferred from DNA sequencing data indicates that C. simplicipinna experienced a recent population contraction without retreating to a common refugium during the last glacial period. The results derived from SSR data also showed that C. simplicipinna underwent past effective population contraction, likely during the Pleistocene. Conclusions Some genetic features of C. simplicipinna such as having high genetic differentiation among the populations, a clear genetic structure and a recent population contraction could provide guidelines for protecting this endangered species from extinction. Furthermore, the genetic features with population dynamics of the species in our study would help provide insights and guidelines for protecting other endangered species effectively.

2014-01-01

40

Genetic structuring and recent demographic history of red pandas (Ailurus fulgens) inferred from microsatellite and mitochondrial DNA.  

PubMed

Clarification of the genetic structure and population history of a species can shed light on the impacts of landscapes, historical climate change and contemporary human activities and thus enables evidence-based conservation decisions for endangered organisms. The red panda (Ailurus fulgens) is an endangered species distributing at the edge of the Qinghai-Tibetan Plateau and is currently subject to habitat loss, fragmentation and population decline, thus representing a good model to test the influences of the above-mentioned factors on a plateau edge species. We combined nine microsatellite loci and 551?bp of mitochondrial control region (mtDNA CR) to explore the genetic structure and demographic history of this species. A total of 123 individuals were sampled from 23 locations across five populations. High levels of genetic variation were identified for both mtDNA and microsatellites. Phylogeographic analyses indicated little geographic structure, suggesting historically wide gene flow. However, microsatellite-based Bayesian clustering clearly identified three groups (Qionglai-Liangshan, Xiaoxiangling and Gaoligong-Tibet). A significant isolation-by-distance pattern was detected only after removing Xiaoxiangling. For mtDNA data, there was no statistical support for a historical population expansion or contraction for the whole sample or any population except Xiaoxiangling where a signal of contraction was detected. However, Bayesian simulations of population history using microsatellite data did pinpoint population declines for Qionglai, Xiaoxiangling and Gaoligong, demonstrating significant influences of human activity on demography. The unique history of the Xiaoxiangling population plays a critical role in shaping the genetic structure of this species, and large-scale habitat loss and fragmentation is hampering gene flow among populations. The implications of our findings for the biogeography of the Qinghai-Tibetan Plateau, subspecies classification and conservation of red pandas are discussed. PMID:21585580

Hu, Yibo; Guo, Yu; Qi, Dunwu; Zhan, Xiangjiang; Wu, Hua; Bruford, Michael W; Wei, Fuwen

2011-07-01

41

Nautilus pompilius Life History and Demographics at the Osprey Reef Seamount, Coral Sea, Australia  

PubMed Central

Nautiloids are the subject of speculation as to their threatened status arising from the impacts of targeted fishing for the ornamental shell market. Life history knowledge is essential to understand the susceptibility of this group to overfishing and to the instigation of management frameworks. This study provides a comprehensive insight into the life of Nautilus in the wild. At Osprey Reef from 1998–2008, trapping for Nautilus was conducted on 354 occasions, with 2460 individuals of one species, Nautilus pompilius, captured and 247 individuals recaptured. Baited remote underwater video systems (BRUVS) were deployed on 15 occasions and six remotely operated vehicle (ROV) dives from 100–800 m were conducted to record Nautilus presence and behavior. Maturity, sex and size data were recorded, while measurements of recaptured individuals allowed estimation of growth rates to maturity, and longevity beyond maturity. We found sexual dimorphism in size at maturity (males: 131.9±SD?=?2.6 mm; females: 118.9±7.5 mm shell diameter) in a population dominated by mature individuals (58%). Mean growth rates of 15 immature recaptured animals were 0.061±0.023 mm day?1 resulting in an estimate of around 15.5 years to maturation. Recaptures of mature animals after five years provide evidence of a lifespan exceeding 20 years. Juvenile Nautilus pompilius feeding behavior was recorded for the first time within the same depth range (200–610 m) as adults. Our results provide strong evidence of a K-selected life history for Nautilus from a detailed study of a ‘closed’ wild population. In conjunction with population size and density estimates established for the Osprey Reef Nautilus, this work allows calculations for sustainable catch and provides mechanisms to extrapolate these findings to other extant nautiloid populations (Nautilus and Allonautilus spp.) throughout the Indo-Pacific.

Dunstan, Andrew J.; Ward, Peter D.; Marshall, N. Justin

2011-01-01

42

Nautilus pompilius life history and demographics at the Osprey Reef Seamount, Coral Sea, Australia.  

PubMed

Nautiloids are the subject of speculation as to their threatened status arising from the impacts of targeted fishing for the ornamental shell market. Life history knowledge is essential to understand the susceptibility of this group to overfishing and to the instigation of management frameworks. This study provides a comprehensive insight into the life of Nautilus in the wild. At Osprey Reef from 1998-2008, trapping for Nautilus was conducted on 354 occasions, with 2460 individuals of one species, Nautilus pompilius, captured and 247 individuals recaptured. Baited remote underwater video systems (BRUVS) were deployed on 15 occasions and six remotely operated vehicle (ROV) dives from 100-800 m were conducted to record Nautilus presence and behavior. Maturity, sex and size data were recorded, while measurements of recaptured individuals allowed estimation of growth rates to maturity, and longevity beyond maturity. We found sexual dimorphism in size at maturity (males: 131.9±SD?=?2.6 mm; females: 118.9±7.5 mm shell diameter) in a population dominated by mature individuals (58%). Mean growth rates of 15 immature recaptured animals were 0.061±0.023 mm day(-1) resulting in an estimate of around 15.5 years to maturation. Recaptures of mature animals after five years provide evidence of a lifespan exceeding 20 years. Juvenile Nautilus pompilius feeding behavior was recorded for the first time within the same depth range (200-610 m) as adults. Our results provide strong evidence of a K-selected life history for Nautilus from a detailed study of a 'closed' wild population. In conjunction with population size and density estimates established for the Osprey Reef Nautilus, this work allows calculations for sustainable catch and provides mechanisms to extrapolate these findings to other extant nautiloid populations (Nautilus and Allonautilus spp.) throughout the Indo-Pacific. PMID:21347356

Dunstan, Andrew J; Ward, Peter D; Marshall, N Justin

2011-01-01

43

Comparative phylogeography and demographic history of European shads (Alosa alosa and A. fallax) inferred from mitochondrial DNA  

PubMed Central

Background Comparative broad-scale phylogeographic studies of aquatic organisms provide insights on biotic responses to the paleohydrological dynamics associated with climatic oscillations. These insights can be used to formulate a framework for understanding the evolutionary history of a species or closely related taxa as well as aid in predictive modeling of further responses to climate change. Anadromous fishes constitute interesting models for understanding the relative importance of environmental versus biological factors in shaping intraspecific genetic substructure on the interface between marine and freshwater realms. European shads, Alosa alosa and A. fallax are anadromous species that have persisted through historical large-scale environmental perturbations and now additionally face an array of anthropogenic challenges. A comprehensive phylogeographic investigation of these species is needed to provide insights on both the historical processes that have shaped their extant genetic structure and diversity, and the prospects for their future management and conservation. Results Despite introgressive hybridization, A. alosa and A. fallax are genetically divergent, congruent with previous studies. Three similarly divergent mtDNA clades were recognized within both A. fallax and A. alosa, most likely originating during common periods of isolation during the Pleistocene among the studied oceanographic regions. Periods of basin isolation apparently extended to the Black Sea as additional Alosa clades occur there. The present day geographic distribution of genetic diversity within European Alosa sp. suggests the existence of a strong but permeable barrier between the Atlantic and Mediterranean seas, as shown for a number of other aquatic species. Overall mtDNA diversity is considerably lower for A. alosa compared to A. fallax, suggesting that the former species is more sensitive to climatic as well as anthropogenic changes. For A. fallax, migration from the Mediterranean to the Atlantic was detected but not in the opposite direction, with colonization of the North Atlantic probably occurring after last glacial maximum. Conclusion The similar haplotype network topologies between the two species support a common intraspecific history of isolation. Despite these similarities, A. alosa and A. fallax have clearly responded differently to the hydrological dynamics of the Pleistocene, as reflected in their distinct demographic histories. As the species additionally occupy different ecological niches it should not be surprising that they differ in resilience to natural or human-mediated climatic changes. For A. fallax, it is further clear that its demographic response to large-scale hydrological events is not synchronized between the Atlantic and Mediterranean basins. These regional and species-specific differences should be incorporated into future predictive modeling of biological response to climate change as well as current management concepts.

2012-01-01

44

Contrasting recombination patterns and demographic histories of the plant pathogen Ralstonia solanacearum inferred from MLSA  

PubMed Central

We used multilocus sequence analysis (MLSA) on a worldwide collection of the plant pathogenic Ralstonia solanacearum (Betaproteobacteria) to retrace its complex evolutionary history. Using genetic imprints left during R. solanacearum evolution, we were able to delineate distinct evolutionary complex displaying contrasting dynamics. Among the phylotypes already described (I, IIA, IIB, III, IV), eight groups of strains with distinct evolutionary patterns, named clades, were identified. From our recombination analysis, we identified 21 recombination events that occurred within and across these lineages. Although appearing the most divergent and ancestral phylotype, phylotype IV was inferred as a gene donor for the majority of the recombination events that we detected. Whereas this phylotype apparently fuelled the species diversity, ongoing diversification was mainly detected within phylotype I, IIA and III. These three groups presented a recent expanding population structure, a high level of homologous recombination and evidences of long-distance migrations. Factors such as adaptation to a specific host or intense trading of infected crops may have promoted this diversification. Whether R. solanacearum lineages will eventually evolve in distinct species remains an open question. The intensification of cropping and increase of geographical dispersion may favour situations of phylotype sympatry and promote higher exchange of key factors for host adaptation from their common genetic pool.

Wicker, Emmanuel; Lefeuvre, Pierre; de Cambiaire, Jean-Charles; Lemaire, Christophe; Poussier, Stephane; Prior, Philippe

2012-01-01

45

Contrasting recombination patterns and demographic histories of the plant pathogen Ralstonia solanacearum inferred from MLSA.  

PubMed

We used multilocus sequence analysis (MLSA) on a worldwide collection of the plant pathogenic Ralstonia solanacearum (Betaproteobacteria) to retrace its complex evolutionary history. Using genetic imprints left during R. solanacearum evolution, we were able to delineate distinct evolutionary complex displaying contrasting dynamics. Among the phylotypes already described (I, IIA, IIB, III, IV), eight groups of strains with distinct evolutionary patterns, named clades, were identified. From our recombination analysis, we identified 21 recombination events that occurred within and across these lineages. Although appearing the most divergent and ancestral phylotype, phylotype IV was inferred as a gene donor for the majority of the recombination events that we detected. Whereas this phylotype apparently fuelled the species diversity, ongoing diversification was mainly detected within phylotype I, IIA and III. These three groups presented a recent expanding population structure, a high level of homologous recombination and evidences of long-distance migrations. Factors such as adaptation to a specific host or intense trading of infected crops may have promoted this diversification. Whether R. solanacearum lineages will eventually evolve in distinct species remains an open question. The intensification of cropping and increase of geographical dispersion may favour situations of phylotype sympatry and promote higher exchange of key factors for host adaptation from their common genetic pool. PMID:22094345

Wicker, Emmanuel; Lefeuvre, Pierre; de Cambiaire, Jean-Charles; Lemaire, Christophe; Poussier, Stéphane; Prior, Philippe

2012-05-01

46

Effects of Pleistocene climatic fluctuations on the phylogeographic and demographic histories of Pacific herring (Clupea pallasii).  

PubMed

We gathered mitochondrial DNA sequences (557 bp from the control region in 935 specimens and 668 bp of the cytochrome b gene in 139 specimens) of Pacific herring collected from 20 nearshore localities spanning the species' extensive range along the North Pacific coastlines of Asia and North America. Haplotype diversity and nucleotide diversity were high, and three major phylogeographic lineages (sequence divergences ca. 1.5%) were detected. Using a variety of phylogenetic methods, coalescent reasoning, and molecular dating interpreted in conjunction with paleoclimatic and physiographic evidence, we infer that the genetic make-up of extant populations of C. pallasii was shaped by Pleistocene environmental impacts on the historical demography of this species. A deep genealogical split that cleanly distinguishes populations in the western vs. eastern North Pacific probably originated as a vicariant separation associated with a glacial cycle that drove the species southward and isolated two ancestral populations in Asia and North America. Another deep genealogical split may have involved either a vicariant isolation of a third herring lineage (perhaps originally in the Gulf of California) or it may have resulted simply from the long coalescent times that are possible in large populations. Coalescent analyses showed that all the three evolutionary lineages of C. pallasii experienced major expansions in their most recent histories after having remained more stable in the preceding periods. Independent of the molecular calibration chosen, populations of C. pallasii appear to have remained stable or grown throughout the periods that covered at least two major glaciations, and probably more. PMID:21824211

Liu, Jin-Xian; Tatarenkov, Andrey; Beacham, Terry D; Gorbachev, Victor; Wildes, Sharon; Avise, John C

2011-09-01

47

Demographic history of Diadema antillarum, a keystone herbivore on Caribbean reefs.  

PubMed Central

The sea urchin Diadema antillarum was the most important herbivore on Caribbean reefs until 1983, when mass mortality reduced its populations by more than 97%. Knowledge of its past demography is essential to reconstruct reef ecology as it was before human impact, which has been implicated as having caused high pre-mortality Diadema abundance. To determine the history of its population size, we sequenced the ATPase 6 and 8 region of mitochondrial DNA from populations in the Caribbean and in the eastern Atlantic (which was not affected by the mass mortality), as well as from the eastern Pacific D. mexicanum. The Caribbean population harbours an order of magnitude more molecular diversity than those of the eastern Pacific or the eastern Atlantic and, despite the recent mass mortality, its DNA sequences bear the genetic signature of a previous population expansion. By estimating mutation rates from divergence between D. antillarum and D. mexicanum, that were separated at a known time by the Isthmus of Panama, and by using estimates of effective population size derived from mismatch distributions and a maximum likelihood coalescence algorithm, we date the expansion as having occurred no more recently than 100 000 years before the present. Thus, Diadema was abundant in the Caribbean long before humans could have affected ecological processes; the genetic data contain no evidence of a recent, anthropogenically caused, population increase.

Lessios, H. A.; Garrido, M. J.; Kessing, B. D.

2001-01-01

48

Concordant phylogeographies of 2 malaria vectors attest to common spatial and demographic histories.  

PubMed

The phylogeography of South American lineages is a topic of heated debate. Although a single process is unlikely to describe entire ecosystems, related species, which incur similar habitat limitations, can inform the history for a subsection of assemblages. We compared the phylogeographic patterns of the cytochrome oxidase I marker from Anopheles triannulatus (N = 72) and previous results for A. darlingi (N = 126) in a broad portion of their South American distributions. Both species share similar population subdivisions, with aggregations northeast of the Amazon River, in southern coastal Brazil and 2 regions in central Brazil. The average capital EF, Cyrillic(ST) between these groups was 0.39 for A. triannulatus. Populations northeast of the Amazon and in southeastern Brazil are generally reciprocally monophyletic to the remaining groups. Based on these initial analyses, we constructed the a priori hypothesis that the Amazon and regions of high declivity pose geographic barriers to dispersal in these taxa. Mantel tests confirmed that these areas block gene flow for more than 1000 km for both species. The efficacy of these impediments was tested using landscape genetics, which could not reject our a priori hypothesis but did reject simpler scenarios. Results form summary statistics and phylogenetics suggest that both lineages originated in central Amazonia (south of the Amazon River) during the late Pleistocene (579 000 years ago) and that they followed the same paths of expansion into their contemporary distributions. These results may have implications for other species sharing similar ecological limitations but probably are not applicable as a general paradigm of Neotropical biogeography. PMID:20511380

Pedro, Pedro M; Uezu, Alexandre; Sallum, Maria Anice Mureb

2010-01-01

49

Demographic history, genetic structure and gene flow in a steppe-associated raptor species  

PubMed Central

Background Environmental preferences and past climatic changes may determine the length of time during which a species range has contracted or expanded from refugia, thereby influencing levels of genetic diversification. Connectivity among populations of steppe-associated taxa might have been maximal during the long glacial periods, and interrupted only during the shorter interglacial phases, potentially resulting in low levels of genetic differentiation among populations. We investigated this hypothesis by exploring patterns of genetic diversity, past demography and gene flow in a raptor species characteristic of steppes, the Montagu's harrier (Circus pygargus), using mitochondrial DNA data from 13 breeding populations and two wintering populations. Results Consistent with our hypothesis, Montagu's harrier has relatively low genetic variation at the mitochondrial DNA. The highest levels of genetic diversity were found in coastal Spain, France and central Asia. These areas, which were open landscapes during the Holocene, may have acted as refugia when most of the European continent was covered by forests. We found significant genetic differentiation between two population groups, at the SW and NE parts of the species' range. Two events of past population growth were detected, and occurred ca. 7500-5500 and ca. 3500-1000 years BP in the SW and NE part of the range respectively. These events were likely associated with vegetation shifts caused by climate and human-induced changes during the Holocene. Conclusions The relative genetic homogeneity observed across populations of this steppe raptor may be explained by a short isolation time, relatively recent population expansions and a relaxed philopatry. We highlight the importance of considering the consequence of isolation and colonization processes in order to better understand the evolutionary history of steppe species.

2011-01-01

50

Life history and demographics of the endangered birdwing pearlymussel (Lemiox rimosus) (Bivalvia: Unionidae)  

USGS Publications Warehouse

The life history and population demography of the endangered birdwing pearlymussel (Lemiox rimosus) were studied in the Clinch and Duck rivers, Tennessee. Reproducing populations of L. rimosus now occur only in the Clinch, Duck and Powell rivers, as the species is considered extirpated from the remaining portions of its range in the Tennessee River drainage. Females are long-term winter brooders, typically gravid from Oct. to May. Glochidia are contained in the outer gills and are released in association with a mantle-lure that resembles a small freshwater snail. Estimated fecundity, based on 8 gravid females collected from the Clinch and Duck rivers, ranged from 4132 to 58,700 glochidia/mussel. Seven fish species were tested for suitability as hosts for glochidia, and five darter species were confirmed through induced infestations: Etheostoma blennioides, E. camurum, E. rufilineatum, E. simoterum and E. zonale. Ages of L. rimosus shells were determined by thin-sectioning and ranged from 3 to 15 y in both rivers. Shell growth was higher and maximum size greater in males than females in both rivers. Shell growth was greatest in the Duck River. Densities of L. rimosus in the Clinch River were maintained at seemingly stable but low levels ranging from 0.07 to 0.27 m-2 from 20042007, and in the Duck River at similar but higher levels ranging from 0.6 to 1.0 m -2 from 20042006. In the latter river, abundance has increased since 1988, likely due to improved minimum flows and dissolved oxygen levels in water releases from a reservoir upstream. ?? 2010, American Midland Naturalist.

Jones, J. W.; Neves, R. J.; Ahlstedt, S. A.; Hubbs, D.; Johnson, M.; Dan, H.; Ostby, B. J. K.

2010-01-01

51

A brief history of the changing occupations and demographics of coleopterists from the 18th through the 20th century.  

PubMed

Systematic entomology flourished as a branch of Natural History from the 1750s to the end of the nineteenth century. During this interval, the "era of Heroic Entomology," the majority of workers in the field were dedicated amateurs. This article traces the demographic and occupational shifts in entomology through this 150-year interval and into the early twentieth century. The survey is based on entomologists who studied beetles (Coleoptera), and who named sufficient numbers of species to have their own names abbreviated by subsequent taxonomists. In the eighteenth century, 27 entomologists achieved this level of prominence, of whom 37% were academics, 19% were doctors, 11% had private incomes, 19% were clergymen, and 8% were government officials. Many of those with private incomes were members of the European aristocracy, and all but one were European men. The nineteenth century list included 192 entomologists, of whom 17% were academics, 16% were museum curators, 2% were school teachers, 15% were doctors, 6% were military men, 7% were merchants, 2% were government entomologists, 6% had private incomes, 5% were clergymen, 5% were government officials, and 4% were lawyers. The demographics of entomology shifted dramatically in the nineteenth century. Whereas many of the noteworthy entomologists of the eighteenth century were German, Swedish, or French, in the nineteenth century, many more European countries are represented, and almost one-fifth of the noteworthy entomologists were from the United States. The nineteenth century list, like the eighteenth century list, contains no women. By the twentieth century, 63% of 178 noteworthy systematic entomologists were paid professionals, teaching entomology courses in universities, or studying insect taxonomy in museums and government-sponsored laboratories. Only one person on the twentieth century list had a private income, but women (ten individuals) were included on the list for the first time. PMID:23928824

Elias, Scott A

2014-01-01

52

Gene flow and demographic history of the mangrove crab Neosarmatium meinerti: A case study from the western Indian Ocean  

NASA Astrophysics Data System (ADS)

Most marine organisms are characterized by at least one planktonic phase during their life history, potentially allowing interconnection of populations separated by several hundred kilometers. For many years, the idea that marine species are genetically homogenous throughout their range of distribution, due to passive larval transport, has been a paradigm. Nowadays, a growing number of studies underline the existence of boundaries in the marine realm and highlight how larval dispersal is a complex process depending on biotic as well as abiotic factors. Marine fragmented habitats, such as atolls, mangroves and estuaries, are optimal systems for investigating the marine dispersion process under a metapopulation approach, since populations can be geographically defined a priori as opposed to those occupying open marine environments. Within this frame, the present paper investigates the population genetic structure and the demographic history of the mangrove crab Neosarmatium meinerti within the western Indian Ocean by partial sequences of the mitochondrial DNA cytochrome oxidase subunit I. A total of 167 specimens were sampled from six mangrove sites distributed along the East African coast, from Kenya to South Africa, also including a mangrove forest located on Mahé Island, Seychelles. A sharp genetic break between the mainland and the Seychelles is recorded, revealing the existence of two historically distinct groups that can be defined as independent evolutionary units. Gene flow along the East African coast appears to be high enough to form a single metapopulation, probably by means of stepping stone populations. Otherwise, this mainland metapopulation is currently under expansion through a gradual moving front from the subtropical toward the equatorial populations.

Ragionieri, Lapo; Cannicci, Stefano; Schubart, Christoph D.; Fratini, Sara

2010-01-01

53

Recent demographic history and present fine-scale structure in the Northwest Atlantic leatherback (Dermochelys coriacea) turtle population.  

PubMed

The leatherback turtle Dermochelys coriacea is the most widely distributed sea turtle species in the world. It exhibits complex life traits: female homing and migration, migrations of juveniles and males that remain poorly known, and a strong climatic influence on resources, breeding success and sex-ratio. It is consequently challenging to understand population dynamics. Leatherbacks are critically endangered, yet the group from the Northwest Atlantic is currently considered to be under lower risk than other populations while hosting some of the largest rookeries. Here, we investigated the genetic diversity and the demographic history of contrasted rookeries from this group, namely two large nesting populations in French Guiana, and a smaller one in the French West Indies. We used 10 microsatellite loci, of which four are newly isolated, and mitochondrial DNA sequences of the control region and cytochrome b. Both mitochondrial and nuclear markers revealed that the Northwest Atlantic stock of leatherbacks derives from a single ancestral origin, but show current genetic structuration at the scale of nesting sites, with the maintenance of migrants amongst rookeries. Low nuclear genetic diversities are related to founder effects that followed consequent bottlenecks during the late Pleistocene/Holocene. Most probably in response to climatic oscillations, with a possible influence of early human hunting, female effective population sizes collapsed from 2 million to 200. Evidence of founder effects and high numbers of migrants make it possible to reconsider the population dynamics of the species, formerly considered as a metapopulation model: we propose a more relaxed island model, which we expect to be a key element in the currently observed recovering of populations. Although these Northwest Atlantic rookeries should be considered as a single evolutionary unit, we stress that local conservation efforts remain necessary since each nesting site hosts part of the genetic diversity and species history. PMID:23516429

Molfetti, Erica; Vilaça, Sibelle Torres; Georges, Jean-Yves; Plot, Virginie; Delcroix, Eric; Le Scao, Rozen; Lavergne, Anne; Barrioz, Sébastien; dos Santos, Fabrício Rodrigues; de Thoisy, Benoît

2013-01-01

54

Recent Demographic History and Present Fine-Scale Structure in the Northwest Atlantic Leatherback (Dermochelys coriacea) Turtle Population  

PubMed Central

The leatherback turtle Dermochelys coriacea is the most widely distributed sea turtle species in the world. It exhibits complex life traits: female homing and migration, migrations of juveniles and males that remain poorly known, and a strong climatic influence on resources, breeding success and sex-ratio. It is consequently challenging to understand population dynamics. Leatherbacks are critically endangered, yet the group from the Northwest Atlantic is currently considered to be under lower risk than other populations while hosting some of the largest rookeries. Here, we investigated the genetic diversity and the demographic history of contrasted rookeries from this group, namely two large nesting populations in French Guiana, and a smaller one in the French West Indies. We used 10 microsatellite loci, of which four are newly isolated, and mitochondrial DNA sequences of the control region and cytochrome b. Both mitochondrial and nuclear markers revealed that the Northwest Atlantic stock of leatherbacks derives from a single ancestral origin, but show current genetic structuration at the scale of nesting sites, with the maintenance of migrants amongst rookeries. Low nuclear genetic diversities are related to founder effects that followed consequent bottlenecks during the late Pleistocene/Holocene. Most probably in response to climatic oscillations, with a possible influence of early human hunting, female effective population sizes collapsed from 2 million to 200. Evidence of founder effects and high numbers of migrants make it possible to reconsider the population dynamics of the species, formerly considered as a metapopulation model: we propose a more relaxed island model, which we expect to be a key element in the currently observed recovering of populations. Although these Northwest Atlantic rookeries should be considered as a single evolutionary unit, we stress that local conservation efforts remain necessary since each nesting site hosts part of the genetic diversity and species history.

Molfetti, Erica; Torres Vilaca, Sibelle; Georges, Jean-Yves; Plot, Virginie; Delcroix, Eric; Le Scao, Rozen; Lavergne, Anne; Barrioz, Sebastien; dos Santos, Fabricio Rodrigues; de Thoisy, Benoit

2013-01-01

55

Low genetic diversity in wide-spread Eurasian liver fluke Opisthorchis felineus suggests special demographic history of this trematode species.  

PubMed

Opisthorchis felineus or Siberian liver fluke is a trematode parasite (Opisthorchiidae) that infects the hepato-biliary system of humans and other mammals. Despite its public health significance, this wide-spread Eurasian species is one of the most poorly studied human liver flukes and nothing is known about its population genetic structure and demographic history. In this paper, we attempt to fill this gap for the first time and to explore the genetic diversity in O. felineus populations from Eastern Europe (Ukraine, European part of Russia), Northern Asia (Siberia) and Central Asia (Northern Kazakhstan). Analysis of marker DNA fragments from O. felineus mitochondrial cytochrome c oxidase subunit 1 and 3 (cox1, cox3) and nuclear rDNA internal transcribed spacer 1 (ITS1) sequences revealed that genetic diversity is very low across the large geographic range of this species. Microevolutionary processes in populations of trematodes may well be influenced by their peculiar biology. Nevertheless, we suggest that lack of population genetics structure observed in O. felineus can be primarily explained by the Pleistocene glacial events and subsequent sudden population growth from a very limited group of founders. Rapid range expansion of O. felineus through Asian and European territories after severe bottleneck points to a high dispersal potential of this trematode species. PMID:23634228

Brusentsov, Ilja I; Katokhin, Alexey V; Brusentsova, Irina V; Shekhovtsov, Sergei V; Borovikov, Sergei N; Goncharenko, Grigoriy G; Lider, Lyudmila A; Romashov, Boris V; Rusinek, Olga T; Shibitov, Samat K; Suleymanov, Marat M; Yevtushenko, Andrey V; Mordvinov, Viatcheslav A

2013-01-01

56

Genetic Structure and Demographic History Should Inform Conservation: Chinese Cobras Currently Treated as Homogenous Show Population Divergence  

PubMed Central

An understanding of population structure and genetic diversity is crucial for wildlife conservation and for determining the integrity of wildlife populations. The vulnerable Chinese cobra (Naja atra) has a distribution from the mouth of the Yangtze River down to northern Vietnam and Laos, within which several large mountain ranges and water bodies may influence population structure. We combined 12 microsatellite loci and 1117 bp of the mitochondrial cytochrome b gene to explore genetic structure and demographic history in this species, using 269 individuals from various localities in Mainland China and Vietnam. High levels of genetic variation were identified for both mtDNA and microsatellites. mtDNA data revealed two main (Vietnam + southern China + southwestern China; eastern + southeastern China) and one minor (comprising only two individuals from the westernmost site) clades. Microsatellite data divided the eastern + southeastern China clade further into two genetic clusters, which include individuals from the eastern and southeastern regions, respectively. The Luoxiao and Nanling Mountains may be important barriers affecting the diversification of lineages. In the haplotype network of cytchrome b, many haplotypes were represented within a “star” cluster and this and other tests suggest recent expansion. However, microsatellite analyses did not yield strong evidence for a recent bottleneck for any population or genetic cluster. The three main clusters identified here should be considered as independent management units for conservation purposes. The release of Chinese cobras into the wild should cease unless their origin can be determined, and this will avoid problems arising from unnatural homogenization.

Lin, Long-Hui; Qu, Yan-Fu; Li, Hong; Zhou, Kai-Ya; Ji, Xiang

2012-01-01

57

Revealing the maternal demographic history of Panthera leo using ancient DNA and a spatially explicit genealogical analysis  

PubMed Central

Background Understanding the demographic history of a population is critical to conservation and to our broader understanding of evolutionary processes. For many tropical large mammals, however, this aim is confounded by the absence of fossil material and by the misleading signal obtained from genetic data of recently fragmented and isolated populations. This is particularly true for the lion which as a consequence of millennia of human persecution, has large gaps in its natural distribution and several recently extinct populations. Results We sequenced mitochondrial DNA from museum-preserved individuals, including the extinct Barbary lion (Panthera leo leo) and Iranian lion (P. l. persica), as well as lions from West and Central Africa. We added these to a broader sample of lion sequences, resulting in a data set spanning the historical range of lions. Our Bayesian phylogeographical analyses provide evidence for highly supported, reciprocally monophyletic lion clades. Using a molecular clock, we estimated that recent lion lineages began to diverge in the Late Pleistocene. Expanding equatorial rainforest probably separated lions in South and East Africa from other populations. West African lions then expanded into Central Africa during periods of rainforest contraction. Lastly, we found evidence of two separate incursions into Asia from North Africa, first into India and later into the Middle East. Conclusions We have identified deep, well-supported splits within the mitochondrial phylogeny of African lions, arguing for recognition of some regional populations as worthy of independent conservation. More morphological and nuclear DNA data are now needed to test these subdivisions.

2014-01-01

58

Low Genetic Diversity in Wide-Spread Eurasian Liver Fluke Opisthorchis felineus Suggests Special Demographic History of This Trematode Species  

PubMed Central

Opisthorchis felineus or Siberian liver fluke is a trematode parasite (Opisthorchiidae) that infects the hepato-biliary system of humans and other mammals. Despite its public health significance, this wide-spread Eurasian species is one of the most poorly studied human liver flukes and nothing is known about its population genetic structure and demographic history. In this paper, we attempt to fill this gap for the first time and to explore the genetic diversity in O. felineus populations from Eastern Europe (Ukraine, European part of Russia), Northern Asia (Siberia) and Central Asia (Northern Kazakhstan). Analysis of marker DNA fragments from O. felineus mitochondrial cytochrome c oxidase subunit 1 and 3 (cox1, cox3) and nuclear rDNA internal transcribed spacer 1 (ITS1) sequences revealed that genetic diversity is very low across the large geographic range of this species. Microevolutionary processes in populations of trematodes may well be influenced by their peculiar biology. Nevertheless, we suggest that lack of population genetics structure observed in O. felineus can be primarily explained by the Pleistocene glacial events and subsequent sudden population growth from a very limited group of founders. Rapid range expansion of O. felineus through Asian and European territories after severe bottleneck points to a high dispersal potential of this trematode species.

Brusentsov, Ilja I.; Katokhin, Alexey V.; Brusentsova, Irina V.; Shekhovtsov, Sergei V.; Borovikov, Sergei N.; Goncharenko, Grigoriy G.; Lider, Lyudmila A.; Romashov, Boris V.; Rusinek, Olga T.; Shibitov, Samat K.; Suleymanov, Marat M.; Yevtushenko, Andrey V.; Mordvinov, Viatcheslav A.

2013-01-01

59

Reconciling Deep Calibration and Demographic History: Bayesian Inference of Post Glacial Colonization Patterns in Carcinus aestuarii (Nardo, 1847) and C. maenas (Linnaeus, 1758)  

PubMed Central

A precise inference of past demographic histories including dating of demographic events using Bayesian methods can only be achieved with the use of appropriate molecular rates and evolutionary models. Using a set of 596 mitochondrial cytochrome c oxidase I (COI) sequences of two sister species of European green crabs of the genus Carcinus (C. maenas and C. aestuarii), our study shows how chronologies of past evolutionary events change significantly with the application of revised molecular rates that incorporate biogeographic events for calibration and appropriate demographic priors. A clear signal of demographic expansion was found for both species, dated between 10,000 and 20,000 years ago, which places the expansions events in a time frame following the Last Glacial Maximum (LGM). In the case of C. aestuarii, a population expansion was only inferred for the Adriatic-Ionian, suggestive of a colonization event following the flooding of the Adriatic Sea (18,000 years ago). For C. maenas, the demographic expansion inferred for the continental populations of West and North Europe might result from a northward recolonization from a southern refugium when the ice sheet retreated after the LGM. Collectively, our results highlight the importance of using adequate calibrations and demographic priors in order to avoid considerable overestimates of evolutionary time scales.

Marino, Ilaria A. M.; Pujolar, Jose Martin; Zane, Lorenzo

2011-01-01

60

Five-year reliability of key demographic and life history data collected from self-respondents and next-of-kin.  

PubMed

The ability of study participants or their next-of-kin to provide basic demographic and life history data is of critical importance in epidemiologic studies and government surveys. Most interview studies to date have focused on the reliability of these variables either as self-reported over short periods of time (<2 years) or as reported by the next-of-kin concurrently with the study participant. In a unique reinterview study, the authors examine the concordance of responses 5 years after the initial interview among 196 surviving study participants and 107 next-of-kin respondents of participants who died after the first interview. The reliability of demographic, anthropometric, reproductive, and residential history questions was high overall, with most ? and Spearman rank-correlation coefficients being above 0.80 for both self-respondents and next-of-kin at reinterview in 1985. In particular, almost perfect agreement was observed for year of birth, religion raised, number of children, and age at first birth, whereas agreement was lowest for childhood residential history. Contrary to expectation, the next-of-kin responses were generally as reliable as those of the original participants themselves 5 years after the initial study, providing further support for the usefulness of surrogate respondents in collecting demographic and life history information in epidemiologic investigations when no other source is available. PMID:24841642

Sonderman, Jennifer S; Tarone, Robert E; McLaughlin, Joseph K

2014-07-01

61

ENCOUNTER HISTORY MODELING OF JOINT MARK RECAPTURE, TAG-RESIGHTING AND TAG-RECOVERY DATA UNDER TEMPORARY EMIGRATION  

Microsoft Academic Search

We describe a joint analysis of mark-recapture, tag-resight and tag- recovery data that directly models the encounter history of an animal. The proba- bility of the encounter history for each animal is partitioned into survival, recapture, resighting, and recovery components, and a component for the probability that the animal is never encountered again. Temporary migration enters into the likelihood through

Richard J. Barker; Kenneth P. Burnham; Gary C. White

62

Phylogenetic relationships and demographic histories of the Atherinidae in the Eastern Atlantic and Mediterranean Sea re-examined by Bayesian inference.  

PubMed

The aim of our study is to examine the phylogenetic relationship, divergence times and demographic history of the five close-related Mediterranean and North-eastern Atlantic species/forms of Atherina using the full Bayesian framework for species tree estimation recently implemented in ?BEAST. The inference is made possible by multilocus data using three mitochondrial genes (12S rRNA, 16S rRNA, control region) and one nuclear gene (rhodopsin) from multiple individuals per species available in GenBank. Bayesian phylogenetic analysis of the complete gene dataset produced a tree with strong support for the monophyly of each species, as well as high support for higher level nodes. An old origin of the Atherina group was suggested (19.2 MY), with deep split events within the Atherinidae predating the Messinian Salinity Crisis. Regional genetic substructuring was observed among populations of A. boyeri, with AMOVA and MultiDimensional Scaling suggesting the existence of five groupings (Atlantic/West Mediterranean, Adriatic, Greece, Black Sea and Tunis). The level of subdivision found might be consequence of the hydrographic isolation within the Mediterranean Sea. Bayesian inference of past demographic histories showed a clear signature of demographic expansion for the European coast populations of A. presbyter, possibly linked to post-glacial colonizations, but not for the Azores/Canary Islands, which is expected in isolated populations because of the impossibility of finding new habitats. Within the Mediterranean, signatures of recent demographic expansion were only found for the Adriatic population of A. boyeri, which could be associated with the relatively recent emergence of the Adriatic Sea. PMID:22425706

Pujolar, J M; Zane, L; Congiu, L

2012-06-01

63

A Worldwide Survey of Human Male Demographic History Based on Y-SNP and Y-STR Data from the HGDP-CEPH Populations  

PubMed Central

We have investigated human male demographic history using 590 males from 51 populations in the Human Genome Diversity Project - Centre d’Étude du Polymorphisme Humain worldwide panel, typed with 37 Y-chromosomal Single Nucleotide Polymorphisms and 65 Y-chromosomal Short Tandem Repeats and analyzed with the program Bayesian Analysis of Trees With Internal Node Generation. The general patterns we observe show a gradient from the oldest population time to the most recent common ancestors (TMRCAs) and expansion times together with the largest effective population sizes in Africa, to the youngest times and smallest effective population sizes in the Americas. These parameters are significantly negatively correlated with distance from East Africa, and the patterns are consistent with most other studies of human variation and history. In contrast, growth rate showed a weaker correlation in the opposite direction. Y-lineage diversity and TMRCA also decrease with distance from East Africa, supporting a model of expansion with serial founder events starting from this source. A number of individual populations diverge from these general patterns, including previously documented examples such as recent expansions of the Yoruba in Africa, Basques in Europe, and Yakut in Northern Asia. However, some unexpected demographic histories were also found, including low growth rates in the Hazara and Kalash from Pakistan and recent expansion of the Mozabites in North Africa.

Shi, Wentao; Ayub, Qasim; Vermeulen, Mark; Shao, Rong-guang; Zuniga, Sofia; van der Gaag, Kristiaan; de Knijff, Peter; Kayser, Manfred; Xue, Yali; Tyler-Smith, Chris

2010-01-01

64

Distinguishing the effects of selection from demographic history in the genetic variation of two sister passerines based on mitochondrial-nuclear comparison.  

PubMed

Determining the mechanisms responsible for the distribution of genetic diversity in natural populations has occupied a central role in molecular evolution. Our study was motivated by the unprecedented observation that a widespread Eurasian flycatcher, Ficedula albicilla, exhibited no variation at the mitochondrial DNA (mtDNA) ND2 gene in 75 individuals sampled over a 5000-km distance. In contrast, its sister species, F. parva, had low but considerably higher levels of mtDNA variation. We assessed whether natural selection or demographic factors could explain the absence of mtDNA variation in F. albicilla. Eighteen nuclear genes were sequenced to estimate the two species' phylogeographic histories, and for comparison to the mtDNA data. Multilocus coalescence analyses suggested that F. albicilla experienced a population expansion perhaps following a population bottleneck. Simulations based on this demographic history, however, did not replicate the extremely low level of mtDNA variation. Historical range changes based on ecological niche models also failed to explain the observed mtDNA patterns. Neutrality tests (DHEW and ML-HKA) suggested a non-neutral pattern in the mtDNA of F. albicilla. We found a transmembrane-skewed distribution of nonsynonymous substitutions between the two species, three of which caused functional change; the results implied that positive selection could have targeted mtDNA. Several lines of evidence support selection rather than demographic history as the main force influencing the patterns of mtDNA variation. Despite the influence of natural selection, many of the phylogeographic inferences derived from mtDNA were robust, including species limits and a high level of gene flow among populations within species. PMID:24619180

Hung, C-M; Zink, R M

2014-07-01

65

Demographic histories of adaptively diverged riparian and non-riparian species of Ainsliaea (Asteraceae) inferred from coalescent analyses using multiple nuclear loci  

PubMed Central

Background Understanding demographic histories, such as divergence time, patterns of gene flow, and population size changes, in ecologically diverging lineages provide implications for the process and maintenance of population differentiation by ecological adaptation. This study addressed the demographic histories in two independently derived lineages of flood-resistant riparian plants and their non-riparian relatives [Ainsliaea linearis (riparian) and A. apiculata (non-riparian); A. oblonga (riparian) and A. macroclinidioides (non-riparian); Asteraceae] using an isolation-with-migration (IM) model based on variation at 10 nuclear DNA loci. Results The highest posterior probabilities of the divergence time parameters were estimated to be ca. 25,000 years ago for A. linearis and A. apiculata and ca. 9000 years ago for A. oblonga and A. macroclinidioides, although the confidence intervals of the parameters had broad ranges. The likelihood ratio tests detected evidence of historical gene flow between both riparian/non-riparian species pairs. The riparian populations showed lower levels of genetic diversity and a significant reduction in effective population sizes compared to the non-riparian populations and their ancestral populations. Conclusions This study showed the recent origins of flood-resistant riparian plants, which are remarkable examples of plant ecological adaptation. The recent divergence and genetic signatures of historical gene flow among riparian/non-riparian species implied that they underwent morphological and ecological differentiation within short evolutionary timescales and have maintained their species boundaries in the face of gene flow. Comparative analyses of adaptive divergence in two sets of riparian/non-riparian lineages suggested that strong natural selection by flooding had frequently reduced the genetic diversity and size of riparian populations through genetic drift, possibly leading to fixation of adaptive traits in riparian populations. The two sets of riparian/non-riparian lineages showed contrasting patterns of gene flow and genetic differentiation, implying that each lineage showed different degrees of reproductive isolation and that they had experienced unique evolutionary and demographic histories in the process of adaptive divergence.

2012-01-01

66

Socio-Demographic, Clinical and Behavioral Characteristics Associated with a History of Suicide Attempts among Psychiatric Outpatients: A Case Control Study in a Northern Mexican City  

PubMed Central

Background: Little is known about the epidemiology of suicide attempts among psychiatric outpatients in Mexico. This study was aimed to determine the socio-demographic, clinical and behavioral characteristics associated with suicide attempts in psychiatric outpatients in two public hospitals in Durango, Mexico. Methods: Two hundred seventy six psychiatric outpatients (154 suicide attempters and 122 patients without suicide attempt history) attended the two public hospitals in Durango City, Mexico were included in this study. Socio-demographic, clinical and behavioral characteristics were obtained retrospectively from all outpatients and compared in relation to the presence or absence of suicide attempt history. Results: Increased prevalence of suicide attempts was associated with mental and behavioral disorders due to psychoactive substance use (F10-19) (P=0.01), schizophrenia, schizotypal and delusional disorders (F20-29) (P=0.02), mood (affective) disorders (F30-39) (P<0.001), and disorders of adult personality and behavior (F60-69) (P<0.001). Multivariate analysis showed that suicide attempts were associated with young age (OR=1.21, 95% CI: 1.06-1.39; P=0.003), female gender (OR=2.98, 95% CI: 1.55-5.73; P=0.001), urban residence (OR=2.31, 95% CI: 1.17-4.57; P=0.01), memory impairment (OR=1.91, 95% CI: 1.07-3.40; P=0.02), alcohol consumption (OR=2.39, 95% CI: 1.21-4.70; P=0.01), and sexual promiscuity (OR=3.90, 95% CI: 1.74-8.77; P<0.001). Conclusions: We report the association of suicide attempts with socio-demographic, clinical and behavioral characteristics in psychiatric outpatients in Mexico. Results may be useful for an optimal planning of preventive measures against suicide attempts in psychiatric outpatients.

Alvarado-Esquivel, Cosme; Sanchez-Anguiano, Luis Francisco; Arnaud-Gil, Carlos Alberto; Hernandez-Tinoco, Jesus; Molina-Espinoza, Luis Fernando; Rabago-Sanchez, Elizabeth

2014-01-01

67

Population genomics shed light on the demographic and adaptive histories of European invasion in the Pacific oyster, Crassostrea gigas  

PubMed Central

Crassostrea gigas originated from the Pacific coast of Asia, but was introduced into several European countries in the early 1970s. Natural populations have now spread across the length of the western seaboard of Europe. To elucidate the demographic and selective processes at play during this rapid expansion, genome-scan analysis was performed on different populations. High diversities and low differentiation were observed overall, but significant genetic differentiation was found among newly established populations and between the newly established northern group and a nearly panmictic group composed of southern European populations and a population from Japan. Loss of genetic diversity was also seen in the north, likely caused by founder events during colonization. The few strongly supported outlier loci revealed a genetic structure uncorrelated with the north/south differentiation, but grouping two samples from the Danish fjords (northern group) and one from the Dutch Scheldt estuary (southern group) with the one from Japan. These findings might reflect the following: (i) parallel adaptation to similar environmental pressures (fjord-like environment) within each of the two groups or (ii) a footprint of a secondary introduction of an alternative genomic background maintained by multifarious isolation factors. Our results call for a closer examination of adaptive genetic structure in the area of origin.

Rohfritsch, Audrey; Bierne, Nicolas; Boudry, Pierre; Heurtebise, Serge; Cornette, Florence; Lapegue, Sylvie

2013-01-01

68

Selection and demographic history shape the molecular evolution of the gamete compatibility protein bindin in Pisaster sea stars  

PubMed Central

Reproductive compatibility proteins have been shown to evolve rapidly under positive selection leading to reproductive isolation, despite the potential homogenizing effects of gene flow. This process has been implicated in both primary divergence among conspecific populations and reinforcement during secondary contact; however, these two selective regimes can be difficult to discriminate from each other. Here, we describe the gene that encodes the gamete compatibility protein bindin for three sea star species in the genus Pisaster. First, we compare the full-length bindin-coding sequence among all three species and analyze the evolutionary relationships between the repetitive domains of the variable second bindin exon. The comparison suggests that concerted evolution of repetitive domains has an effect on bindin divergence among species and bindin variation within species. Second, we characterize population variation in the second bindin exon of two species: We show that positive selection acts on bindin variation in Pisaster ochraceus but not in Pisaster brevispinus, which is consistent with higher polyspermy risk in P. ochraceus. Third, we show that there is no significant genetic differentiation among populations and no apparent effect of sympatry with congeners that would suggest selection based on reinforcement. Fourth, we combine bindin and cytochrome c oxidase 1 data in isolation-with-migration models to estimate gene flow parameter values and explore the historical demographic context of our positive selection results. Our findings suggest that positive selection on bindin divergence among P. ochraceus alleles can be accounted for in part by relatively recent northward population expansions that may be coupled with the potential homogenizing effects of concerted evolution.

Popovic, Iva; Marko, Peter B; Wares, John P; Hart, Michael W

2014-01-01

69

Selection and demographic history shape the molecular evolution of the gamete compatibility protein bindin in Pisaster sea stars.  

PubMed

Reproductive compatibility proteins have been shown to evolve rapidly under positive selection leading to reproductive isolation, despite the potential homogenizing effects of gene flow. This process has been implicated in both primary divergence among conspecific populations and reinforcement during secondary contact; however, these two selective regimes can be difficult to discriminate from each other. Here, we describe the gene that encodes the gamete compatibility protein bindin for three sea star species in the genus Pisaster. First, we compare the full-length bindin-coding sequence among all three species and analyze the evolutionary relationships between the repetitive domains of the variable second bindin exon. The comparison suggests that concerted evolution of repetitive domains has an effect on bindin divergence among species and bindin variation within species. Second, we characterize population variation in the second bindin exon of two species: We show that positive selection acts on bindin variation in Pisaster ochraceus but not in Pisaster brevispinus, which is consistent with higher polyspermy risk in P. ochraceus. Third, we show that there is no significant genetic differentiation among populations and no apparent effect of sympatry with congeners that would suggest selection based on reinforcement. Fourth, we combine bindin and cytochrome c oxidase 1 data in isolation-with-migration models to estimate gene flow parameter values and explore the historical demographic context of our positive selection results. Our findings suggest that positive selection on bindin divergence among P. ochraceus alleles can be accounted for in part by relatively recent northward population expansions that may be coupled with the potential homogenizing effects of concerted evolution. PMID:24967076

Popovic, Iva; Marko, Peter B; Wares, John P; Hart, Michael W

2014-05-01

70

Low concentrations, potential ecological consequences: synthetic estrogens alter life-history and demographic structures of aquatic invertebrates.  

PubMed

Contraceptive drugs are nowadays found in aquatic environments around the globe. Particularly, 17?-ethinylestradiol (EE2) may act even at low concentrations, such as those recorded in natural ecosystems. We evaluated the physiological effects of EE2 on cyclopoids and calanoids, common copepods in both marine and freshwater communities. We used three EE2 concentrations and assessed its impact on activity of different physiological endpoints: Acetylcholinesterase (neurotransmission), Glutathione S-transferase (detoxifying system), and Caspase-3 (apoptosis). While EE2 exerts, distinctive effect on detoxifying and apoptotic systems, no effect on AChE was observed at environmental doses. Our results show that EE2 exposure affects differently copepod physiology endpoints, altering moulting process, adult recruitment in calanoids and calanoid to cyclopoid ratio. The ecological consequences of this underlying physiological process may affect since life history to population and community structures, and this represent a new aspects of this xenobiotic in natural systems. PMID:23584603

Souza, María Sol; Hallgren, Per; Balseiro, Esteban; Hansson, Lars-Anders

2013-07-01

71

Population structure analyses and demographic history of the malaria vector Anopheles albimanus from the Caribbean and the Pacific regions of Colombia  

PubMed Central

Background Anopheles albimanus is an important malaria vector in some areas throughout its distribution in the Caribbean and the Pacific regions of Colombia, covering three biogeographic zones of the neotropical region, Maracaibo, Magdalena and Chocó. Methods This study was conducted to estimate intra-population genetic diversity, genetic differentiation and demographic history of An. albimanus populations because knowledge of vector population structure is a useful tool to guide malaria control programmes. Analyses were based on mtDNA COI gene sequences and four microsatellite loci of individuals collected in eight populations from the Caribbean and the Pacific regions of Colombia. Results Two distinctive groups were consistently detected corresponding to COI haplotypes from each region. A star-shaped statistical parsimony network, significant and unimodal mismatch distribution, and significant negative neutrality tests together suggest a past demographic expansion or a selective sweep in An. albimanus from the Caribbean coast approximately 21,994 years ago during the late Pleistocene. Overall moderate to low genetic differentiation was observed between populations within each region. However, a significant level of differentiation among the populations closer to Buenaventura in the Pacific region was observed. The isolation by distance model best explained genetic differentiation among the Caribbean region localities: Los Achiotes, Santa Rosa de Lima and Moñitos, but it could not explain the genetic differentiation observed between Turbo (Magdalena providence), and the Pacific region localities (Nuquí, Buenaventura, Tumaco). The patterns of differentiation in the populations from the different biogeographic provinces could not be entirely attributed to isolation by distance. Conclusion The data provide evidence for limited past gene flow between the Caribbean and the Pacific regions, as estimated by mtDNA sequences and current gene flow patterns among An. albimanus populations as measured by MS loci which may be mainly influenced by semi-permeable natural barriers in each biogeographical region that lead to the genetic differences and effective population sizes detected. The relatively high genetic differentiation in the port city of Buenaventura may be the result of specific ecological conditions, human migration and activities and/or differences in effective population sizes. This knowledge could serve to evaluate and coordinate vector control strategies in these regions of Colombia.

2009-01-01

72

Genetic Structure and Demographic History Reveal Migration of the Diamondback Moth Plutella xylostella (Lepidoptera: Plutellidae) from the Southern to Northern Regions of China  

PubMed Central

The diamondback moth Plutella xylostella (Linnaeus) (Lepidoptera: Plutellidae) is one of the most destructive insect pests of cruciferous plants worldwide. Biological, ecological and genetic studies have indicated that this moth is migratory in many regions around the world. Although outbreaks of this pest occur annually in China and cause heavy damage, little is known concerning its migration. To better understand its migration pattern, we investigated the population genetic structure and demographic history of the diamondback moth by analyzing 27 geographical populations across China using four mitochondrial genes and nine microsatellite loci. The results showed that high haplotype diversity and low nucleotide diversity occurred in the diamondback moth populations, a finding that is typical for migratory species. No genetic differentiation among all populations and no correlation between genetic and geographical distance were found. However, pairwise analysis of the mitochondrial genes has indicated that populations from the southern region were more differentiated than those from the northern region. Gene flow analysis revealed that the effective number of migrants per generation into populations of the northern region is very high, whereas that into populations of the southern region is quite low. Neutrality testing, mismatch distribution and Bayesian Skyline Plot analyses based on mitochondrial genes all revealed that deviation from Hardy-Weinberg equilibrium and sudden expansion of the effective population size were present in populations from the northern region but not in those from the southern region. In conclusion, all our analyses strongly demonstrated that the diamondback moth migrates within China from the southern to northern regions with rare effective migration in the reverse direction. Our research provides a successful example of using population genetic approaches to resolve the seasonal migration of insects.

Wei, Shu-Jun; Shi, Bao-Cai; Gong, Ya-Jun; Jin, Gui-Hua; Chen, Xue-Xin; Meng, Xiang-Feng

2013-01-01

73

MOLECULAR DEMOGRAPHIC HISTORY OF THE ANNUAL SUNFLOWERS HELIANTHUS ANNUUS AND H. PETIOLARIS--LARGE EFFECTIVE POPULATION SIZES AND RATES OF LONG-TERM GENE FLOW  

PubMed Central

Hybridization between distinct species may lead to introgression of genes across species boundaries, and this pattern can potentially persist for extended periods as long as selection at some loci or genomic regions prevents thorough mixing of gene pools. However, very few reliable estimates of long-term levels of effective migration are available between hybridizing species throughout their history. Accurate estimates of divergence dates and levels of gene flow require data from multiple unlinked loci as well as an analytical framework that can distinguish between lineage sorting and gene flow and incorporate the effects of demographic changes within each species. Here we use sequence data from 18 anonymous nuclear loci in two broadly sympatric sunflower species, Helianthus annuus and H. petiolaris, analyzed within an “isolation with migration” framework to make genome-wide estimates of the ages of these two species, long-term rates of gene flow between them, and effective population sizes and historical patterns of population growth. Our results indicate that H. annuus and H. petiolaris are approximately one million years old and have exchanged genes at a surprisingly high rate (long-term Nef m estimates of approximately 0.5 in each direction), with somewhat higher rates of introgression from H. annuus into H. petiolaris than vice versa. In addition, each species has undergone dramatic population expansion since divergence, and both species have among the highest levels of genetic diversity reported for flowering plants. Our results provide the most comprehensive estimate to date of long-term patterns of gene flow and historical demography in a nonmodel plant system, and they indicate that species integrity can be maintained even in the face of extensive gene flow over a prolonged period.

Strasburg, Jared L.; Rieseberg, Loren H.

2008-01-01

74

Patterns of Variation at Ustilago maydis Virulence Clusters 2A and 19A Largely Reflect the Demographic History of Its Populations  

PubMed Central

The maintenance of an intimate interaction between plant-biotrophic fungi and their hosts over evolutionary times involves strong selection and adaptative evolution of virulence-related genes. The highly specialised maize pathogen Ustilago maydis is assigned with a high evolutionary capability to overcome host resistances due to its high rates of sexual recombination, large population sizes and long distance dispersal. Unlike most studied fungus-plant interactions, the U. maydis – Zea mays pathosystem lacks a typical gene-for-gene interaction. It exerts a large set of secreted fungal virulence factors that are mostly organised in gene clusters. Their contribution to virulence has been experimentally demonstrated but their genetic diversity within U. maydis remains poorly understood. Here, we report on the intraspecific diversity of 34 potential virulence factor genes of U. maydis. We analysed their sequence polymorphisms in 17 isolates of U. maydis from Europe, North and Latin America. We focused on gene cluster 2A, associated with virulence attenuation, cluster 19A that is crucial for virulence, and the cluster-independent effector gene pep1. Although higher compared to four house-keeping genes, the overall levels of intraspecific genetic variation of virulence clusters 2A and 19A, and pep1 are remarkably low and commensurate to the levels of 14 studied non-virulence genes. In addition, each gene is present in all studied isolates and synteny in cluster 2A is conserved. Furthermore, 7 out of 34 virulence genes contain either no polymorphisms or only synonymous substitutions among all isolates. However, genetic variation of clusters 2A and 19A each resolve the large scale population structure of U. maydis indicating subpopulations with decreased gene flow. Hence, the genetic diversity of these virulence-related genes largely reflect the demographic history of U. maydis populations.

Kellner, Ronny; Hanschke, Christian; Begerow, Dominik

2014-01-01

75

Demographic consequences of climate change and land cover help explain a history of extirpations and range contraction in a declining snake species.  

PubMed

Developing conservation strategies for threatened species increasingly requires understanding vulnerabilities to climate change, in terms of both demographic sensitivities to climatic and other environmental factors, and exposure to variability in those factors over time and space. We conducted a range-wide, spatially explicit climate change vulnerability assessment for Eastern Massasauga (Sistrurus catenatus), a declining endemic species in a region showing strong environmental change. Using active season and winter adult survival estimates derived from 17 data sets throughout the species' range, we identified demographic sensitivities to winter drought, maximum precipitation during the summer, and the proportion of the surrounding landscape dominated by agricultural and urban land cover. Each of these factors was negatively associated with active season adult survival rates in binomial generalized linear models. We then used these relationships to back-cast adult survival with dynamic climate variables from 1950 to 2008 using spatially explicit demographic models. Demographic models for 189 population locations predicted known extant and extirpated populations well (AUC = 0.75), and models based on climate and land cover variables were superior to models incorporating either of those effects independently. These results suggest that increasing frequencies and severities of extreme events, including drought and flooding, have been important drivers of the long-term spatiotemporal variation in a demographic rate. We provide evidence that this variation reflects nonadaptive sensitivity to climatic stressors, which are contributing to long-term demographic decline and range contraction for a species of high-conservation concern. Range-wide demographic modeling facilitated an understanding of spatial shifts in climatic suitability and exposure, allowing the identification of important climate refugia for a dispersal-limited species. Climate change vulnerability assessment provides a framework for linking demographic and distributional dynamics to environmental change, and can thereby provide unique information for conservation planning and management. PMID:24357530

Pomara, Lars Y; LeDee, Olivia E; Martin, Karl J; Zuckerberg, Benjamin

2014-07-01

76

Conservation genetics of a rare Gerbil species: a comparison of the population genetic structures and demographic histories of the locally rare Pygmy Gerbil and the common Anderson's Gerbil  

PubMed Central

Background One of the major challenges in evolutionary biology is identifying rare species and devising management plans to protect them while also sustaining their genetic diversity. However, in attempting a broad understanding of rarity, single-species studies provide limited insights because they do not reveal whether the factors that affect rare species differ from those that affect more common species. To illustrate this important concept and to arrive at a better understanding of the form of rarity characterizing the rare Gerbillus henleyi, we explored its population genetic structure alongside that of the locally common Gerbillus andersoni allenbyi. We trapped gerbils in several locations in Israel's western and inner Negev sand dunes. We then extracted DNA from ear samples, and amplified two mitochondrial sequences: the control region (CR) and the cytochrome oxidase 2 gene (CO2). Results Nucleotide diversity was low for all sequences, especially for the CR of G. a. allenbyi, which showed no diversity. We could not detect any significant population genetic structure in G. henleyi. In contrast, G. a. allenbyi's CO2 sequence showed significant population genetic structure. Pairwise PhiPT comparisons showed low values for G. henleyi but high values for G. a. allenbyi. Analysis of the species' demographic history indicated that G. henleyi's population size has not changed recently, and is under the influence of an ongoing bottleneck. The same analysis for G. a. allenbyi showed that this species has undergone a recent population expansion. Conclusions Comparing the two species, the populations of G. a. allenbyi are more isolated from each other, likely due to the high habitat specificity characterizing this species. The bottleneck pattern found in G. henleyi may be the result of competition with larger gerbil species. This result, together with the broad habitat use and high turnover rate characterizing G. henleyi, may explain the low level of differentiation among its populations. The evidence for a recent population expansion of G. a. allenbyi fits well with known geomorphological data about the formation of the Negev sand dunes and paleontological data about this species' expansion throughout the Levant. In conclusion, we suggest that adopting a comparative approach as presented here can markedly improve our understanding of the causes and effects of rarity, which in turn can allow us to better protect biodiversity patterns.

2010-01-01

77

Encounter history modeling of joint mark-recapture, tag-resighting and tag-recovery data under temporary emigration  

USGS Publications Warehouse

We describe a joint analysis of mark-recapture, tag-resight and tag-recovery data that directly models the encounter history of an animal. The probability of the encounter history for each animal is partitioned into survival, recapture, resighting, and recovery components, and a component for the probability that the animal is never encountered again. Temporary migration enters into the likelihood through the recapture component, and movement of marked animals in and out of the area where they are subject to capture is modeled using a Markov chain. Random temporary emigration and permanent emigration are special cases. An important feature of directly modeling the encounter histories is that covariates that are specific to individuals can be included in the analysis. The model is applied to a brown trout tagging data set and provides strong evidence of Markovian temporary emigration. The new model is needed to provide correct estimates of trout survival probabilities which are shown to depend on the length of the fish at first capture.

Barker, R. J.; Burnham, K. P.; White, G. C.

2004-01-01

78

Joint Cockpit Office: history and role in defense-wide issues regarding avionics displays  

NASA Astrophysics Data System (ADS)

The charter of the Joint Cockpit Office (JCO) is to plan, coordinate and accelerate the transition of advanced development cockpit/crew station technologies critical to crew effectiveness in current and future air vehicles. The JCO helps assure a single, coordinated, and highly integrated cockpit/crew station Science and Technology (S&T) program within and between the Air Force, the Army, and the Navy. It serves as the primary interface and focal point for issues involving these technologies for organizations within and external to the Services. The Services are at the advent of fielding new technologies such as helmet-mounted displays as a primary flight reference. They will most certainly evaluate the use of windowless cockpits to counter the laser threat and allow for less constraining aerodynamic conditions in future vehicle design. The transition to multi-spectral displays in future military and commercial aircraft is imminent. The JCO is well positioned to assess and focus the research needed to safely exploit these new technologies and meet customer requirements. Presently, the JCO is undertaking three initiatives: creation of a joint-service, Cooperative Research and Development Agreement (CRDA) with Lockheed Martin to study the thresholds of virtual helmet-mounted display attributes and effects on pilot performance; management of the Spatial Disorientation Countermeasures program, and facilitation of the actions determined by the DoD Executive Agent for Flat Panel Displays.

O'Connor, John C.; Kraemer, William A.

2000-08-01

79

Demographic transition and demographic imbalance in India  

Microsoft Academic Search

In the coming decades, there will be growing demographic disparity in India and, like economic disparity, this should be a matter of serious concern for our planners and policy-makers. This demographic disparity leading to demographic imbalance may cause considerable social turbulence and may even pose a threat to political stability. Demographers must look far beyond demographic statistics and anticipate the

Ashish Bose

80

Look before You Leap: Underestimating Chinese Student History, Chinese University Setting and Chinese University Steering in Sino-British HE Joint Ventures?  

ERIC Educational Resources Information Center

This article makes the case--in three parts--that many Anglo-Chinese university collaborations (joint ventures) to date have seriously underestimated Chinese (student) history, the Chinese university setting and Chinese national governmental steering as part of the process of "glocalisation". Recent turbulence in this particular HE collaborative…

Dow, Ewan G.

2010-01-01

81

The joint evolutionary histories of Wolbachia and mitochondria in Hypolimnas bolina  

PubMed Central

Background The interaction between the Blue Moon butterfly, Hypolimnas bolina, and Wolbachia has attracted interest because of the high prevalence of male-killing achieved within the species, the ecological consequences of this high prevalence, the intensity of selection on the host to suppress the infection, and the presence of multiple Wolbachia infections inducing different phenotypes. We examined diversity in the co-inherited marker, mtDNA, and the partitioning of this between individuals of different infection status, as a means to investigate the population biology and evolutionary history of the Wolbachia infections. Results Part of the mitochondrial COI gene was sequenced from 298 individuals of known infection status revealing ten different haplotypes. Despite very strong biological evidence that the sample represents a single species, the ten haplotypes did not fall within a monophyletic clade within the Hypolimnas genus, with one haplotype differing by 5% from the other nine. There were strong associations between infection status and mtDNA haplotype. The presence of wBol1 infection in association with strongly divergent haplotypes prompted closer examination of wBol1 genetic variation. This revealed the existence of two cryptic subtypes, wBol1a and wBol1b. The wBol1a infection, by far the most common, was in strict association with the single divergent mtDNA haplotype. The wBol1b infection was found with two haplotypes that were also observed in uninfected specimens. Finally, the wBol2 infection was associated with a large diversity of mtDNA haplotypes, most often shared with uninfected sympatric butterflies. Conclusion This data overall supports the hypothesis that high prevalence of male-killing Wolbachia (wBol1) in H. bolina is associated with very high transmission efficiency rather than regular horizontal transmission. It also suggests this infection has undergone a recent selective sweep and was introduced in this species through introgression. In contrast, the sharing of haplotypes between wBol2-infected and uninfected individuals indicates that this strain is not perfectly transmitted and/or shows a significant level of horizontal transmission.

Charlat, Sylvain; Duplouy, Anne; Hornett, Emily A; Dyson, Emily A; Davies, Neil; Roderick, George K; Wedell, Nina; Hurst, Gregory DD

2009-01-01

82

Demographic life transitions: an alternative theoretical paradigm  

Microsoft Academic Search

Event history analyses, while useful, have limited explanatory power in relation to demographic life transitions. This is because demographic behaviour has a future orientation. People marry, cohabit, have children, divorce or migrate primarily because they have expectations or hopes about how these transitions will affect their lives. Individuals weigh up alternatives about their future within their personal and cultural context.

Peter McDonald

1996-01-01

83

Rupture history of the 2009 L'Aquila (Italy) earthquake from non-linear joint inversion of strong motion and GPS data  

Microsoft Academic Search

We image the rupture history of the 2009 L'Aquila (central Italy) earthquake using a nonlinear joint inversion of strong motion and GPS data. This earthquake ruptured a normal fault striking along the Apennines axis and dipping to the SW. The inferred slip distribution is heterogeneous and characterized by a small, shallow slip patch located up-dip from the hypocenter (9.5 km

A. Cirella; A. Piatanesi; M. Cocco; E. Tinti; L. Scognamiglio; A. Michelini; A. Lomax; E. Boschi

2009-01-01

84

Russia's Demographic "Crisis"  

NSDL National Science Digital Library

The Rand Organization has recently made available via the Web the full text of Russia's Demographic "Crisis." "This volume is an outgrowth of a June 5-6, 1995 conference at which a group of Russian demographers presented the results of their pioneering research on Russia's demographic 'crisis' to American colleagues from the Rand Organization, the University of California-Los Angeles, the University of Southern California, and the International Programs Center of the US Bureau of the Census." The six papers that make up the volume deal with two broad categories: "(1) fertility and family planning; and (2) issues in the area of health and mortality--health status, health care, and population aging." The scope of a Russian demographic crisis is hotly debated, as well as "the interrelations between economic reforms and demographic trends in Russia." Russia's Demographic "Crisis" should shed some light on this topic.

1996-01-01

85

Re-writing the natural history of pain and related symptoms in the joint hypermobility syndrome/Ehlers-Danlos syndrome, hypermobility type.  

PubMed

Joint hypermobility syndrome (JHS) and Ehlers-Danlos syndrome, hypermobility type (EDS-HT) are two clinically overlapping connective tissue disorders characterized by chronic/recurrent pain, joint instability complications, and minor skin changes. Fatigue and headache are also common, although are not yet considered diagnostic criteria. JHS/EDS-HT is a unexpectedly common condition that remains underdiagnosed by most clinicians and pain specialists. This results in interventions limited to symptomatic and non-satisfactory treatments, lacking reasonable pathophysiologic rationale. In this manuscript the fragmented knowledge on pain, fatigue, and headache in JHS/EDS is presented with review of the available published information and a description of the clinical course by symptoms, on the basis of authors' experience. Pathogenic mechanisms are suggested through comparisons with other functional somatic syndromes (e.g., chronic fatigue syndrome, fibromyalgia, and functional gastrointestinal disorders). The re-writing of the natural history of JHS/EDS-HT is aimed to raise awareness among clinical geneticists and specialists treating chronic pain conditions about pain and other complications of JHS/EDS-HT. Symptoms' clustering by disease stage is proposed to investigate both the molecular causes and the symptoms management of JHS/EDS-HT in future studies. PMID:24254847

Castori, Marco; Morlino, Silvia; Celletti, Claudia; Ghibellini, Giulia; Bruschini, Michela; Grammatico, Paola; Blundo, Carlo; Camerota, Filippo

2013-12-01

86

The business of demographics.  

PubMed

The emergence of "demographics" in the past 15 years is a vital tool for American business research and planning. Tracing demographic trends became important for businesses when traditional consumer markets splintered with the enormous changes since the 1960s in US population growth, age structure, geographic distribution, income, education, living arrangements, and life-styles. The mass of reliable, small-area demographic data needed for market estimates and projections became available with the electronic census--public release of Census Bureau census and survey data on computer tape, beginning with the 1970 census. Census Bureau tapes as well as printed reports and microfiche are now widely accessible at low cost through summary tape processing centers designated by the bureau and its 12 regional offices and State Data Center Program. Data accessibility, plummeting computer costs, and businessess' unfamiliarity with demographics spawned the private data industry. By 1984, 70 private companies were offering demographic services to business clients--customized information repackaged from public data or drawn from proprietary data bases created from such data. Critics protest the for-profit use of public data by companies able to afford expensive mainframe computer technology. Business people defend their rights to public data as taxpaying ceitzens, but they must ensure that the data are indeed used for the public good. They must also question the quality of demographic data generated by private companies. Business' demographic expertise will improve when business schools offer training in demography, as few now do, though 40 of 88 graduate-level demographic programs now include business-oriented courses. Lower cost, easier access to business demographics is growing as more census data become available on microcomputer diskettes and through on-line linkages with large data bases--from private data companies and the Census Bureau itself. A directory of private and public demographic resources is appended, including forecasting, consulting and research services available. PMID:12313263

Russell, C

1984-06-01

87

Youth Demographics. Fact Sheet  

ERIC Educational Resources Information Center

This fact sheet compares the numbers of 18-25 year-old residents and citizens by gender, race, ethnicity, geographic distribution, marital status, military status, unemployment, educational attainment, and assesses population trends from 1968-2006. It explores such demographic characteristics of young people using data from the March Annual…

Lopez, Mark Hugo; Marcelo, Karlo Barrios

2006-01-01

88

DEMOGRAPHIC AND HEALTH SURVEYS  

EPA Science Inventory

Demographic and Health Surveys are nationally representative household surveys with large sample sizes of between 5,000 and 30,000 households, typically. DHS surveys provide data for a wide range of monitoring and impact evaluation indicators in the areas of population, health, a...

89

Completing the Demographic Transition  

Microsoft Academic Search

Despite ongoing declines in fertility in many countries, the population of the world is experiencing a period of rapid expansion, and its size is expected to reach 10 billion by the end of the demographic transition. Three causes of this growth are identified and quantified: 1) fertility above the replacement level of two surviving children per woman, 2) continuing declines

John Bongaarts; Rodolfo A. Bulatao

1999-01-01

90

Beyond the demographic transition  

Microsoft Academic Search

Two major demographic movements have dominated population growth in the world during the past thirty years: first, the decline of death rates in the develop­ ing countries, which has brought about unusually rapid population growth, and, second, the rise and subsequent decline of birth rates in some developed countries. The first of these trends was to have been expected because

Arthur A. Campbell

1974-01-01

91

A Brief Demographic Portrait  

ERIC Educational Resources Information Center

This article presents a brief demographic portrait, with particular emphasis on school-related issues, that points to the dire situation of Latino/a education. According to the 2010 Census, the number of Hispanics (the term used in government data) currently was 50,477,594 million, an increase of 43 percent since 2000, making this group the…

Nieto, Sonia

2012-01-01

92

The Demographic Imperative  

ERIC Educational Resources Information Center

As the United States moves toward becoming a "minority-majority" country, what more can--and should--college presidents and governing boards do to provide low-income students and students of color with a pipeline to high-quality education? Ongoing discourse about shifting demographics locally and nationally must be built into institutions'…

Jordan, Stephen M.

2009-01-01

93

Asians in New York City: A Demographic Summary.  

ERIC Educational Resources Information Center

This demographic survey provides the following information on Asian Americans: (1) states with the highest Asian American population; (2) ethnic breakdown among Asians; (3) Asian immigration history and legislation affecting it; (4) individual immigration histories of Asian Americans in New York City (New York), including the Chinese, Japanese,…

Steingasser, Jean; And Others

94

Security Dynamics of Demographic Factors.  

National Technical Information Service (NTIS)

This report presents a framework for understanding the implications of global demographic trends for international and U.S. national Security. One of its goals is to spark discussion between demographers and national security analysts. The document should...

B. Nichiporuk

2000-01-01

95

Demographics of transition objects  

NASA Astrophysics Data System (ADS)

The unusual properties of transition objects (young stars with an optically thin inner disc surrounded by an optically thick outer disc) suggest that significant disc evolution has occurred in these systems. We explore the nature of these systems by examining their demographics, specifically their stellar accretion rates and disc masses Mdisc compared to those of accreting T Tauri stars of comparable age. We find that the transition objects in Taurus occupy a restricted region of the versus Mdisc plane. Compared to non-transition single stars in Taurus, they have stellar accretion rates that are typically ~10 times lower at the same disc mass and median disc masses approximately four times larger. These properties are anticipated by several proposed planet formation theories and suggest that the formation of Jovian mass planets may play a significant role in explaining the origin of at least some transition objects. Considering transition objects as a distinct demographic group among accreting T Tauri stars leads to a tighter relationship between disc masses and stellar accretion rates, with a slope between the two quantities that is close to the value of unity expected in simple theories of disc accretion.

Najita, Joan R.; Strom, Stephen E.; Muzerolle, James

2007-06-01

96

Hominin life history: reconstruction and evolution  

Microsoft Academic Search

In this review we attempt to reconstruct the evolutionary history of hominin life history from extant and fossil evidence. We utilize demographic life history theory and distinguish life history variables, traits such as weaning, age at sexual maturity, and life span, from life history-related variables such as body mass, brain growth, and dental development. The latter are either linked with,

Shannen L. Robson; Bernard Wood

2008-01-01

97

The urban demographic revolution.  

PubMed

According to a report by the German government, there is a real prospect that population growth will soon slow down and produce a much more steady state. Evidence indicates that growth rates of megacities--urban agglomerations of 10 million or more residents--have declined sharply. However, such a decline is misleading because these cities still have to absorb enormous population increments in the next 20 years. In view of this, UN estimates and projections of city size and growth suggest that there will be a growth of megacities, not a decline. Demographically, it is noted that megacities in less developed regions have been growing steadily in absolute terms, even as their rates of population growth have dropped in response to national fertility reductions and economic downturns that have deterred migration from rural areas. Such an unprecedented urban growth could lead to higher rates of mortality, social problems, and poverty, as well as environmental concerns. Overall, effective urban governance is needed to ensure the well-being of all residents; and the procedure of estimation and projection of megacity populations should be improved. PMID:12349763

Brockerhoff, M

2000-01-01

98

Demographic Trends: Impact on Schools  

ERIC Educational Resources Information Center

Background: Singapore is experiencing great demographic change. These demographic trends show fewer young people and declining birth rates, greater longevity for ageing generations and an increase in the number of non-Singaporean residents. Statistics also show that more than half of the total population increase in the last decades was…

Chong, Sylvia N. Y.; Cheah, Horn Mun

2010-01-01

99

Joint Contact Stress  

PubMed Central

A joint's normal mechanical history contributes to the maintenance of articular cartilage and underlying bone. Loading facilitates the flow of nutrients into cartilage and waste products away, and additionally provides the mechanical signals essential for normal cell and tissue maintenance. Deleteriously low or high contact stresses have been presumed to result in joint deterioration, and particular aspects of the mechanical environment may facilitate repair of damaged cartilage. For decades, investigators have explored static joint contact stresses (under some more or less arbitrary condition) as a surrogate of the relevant mechanical history. Contact stresses have been estimated in vitro in many joints and in a number of species, although only rarely in vivo. Despite a number of widely varying techniques (and spatial resolutions) to measure these contact stresses, reported ranges of static peak normal stresses are relatively similar from joint to joint across species, and in the range of 0.5 to 5.0 MPa. This suggests vertebrate diarthrodial joints have evolved to achieve similar mechanical design criteria. Available evidence also suggests some disorders of cartilage deterioration are associated with somewhat higher peak pressures ranging from 1-20 MPa, but overlapping the range of normal pressures. Some evidence and considerable logic suggests static contact stresses per se do not predict cartilage responses, but rather temporal aspects of the contact stress history. Static contact stresses may therefore not be a reasonable surrogate for biomechanical studies. Rather, temporal and spatial aspects of the loading history undoubtedly induce beneficial and deleterious biological responses. Finally, since all articular cartilage experiences similar stresses, the concept of a "weight-bearing" versus a "non-weight-bearing" joint seems flawed, and should be abandoned.

Brand, Richard A

2005-01-01

100

Influence of a family history of type 2 diabetes, demographic and clinical data on carotid intima-media thickness in patients with type 1 diabetes: a cross-sectional study  

PubMed Central

Background Intima-media thickness (IMT) of the common carotid artery is a surrogate end point of cardiovascular disease (CVD). Identifying the factors associated with a higher IMT may contribute to the identification of subjects with higher CVD risk. Our objective was to compare the common carotid IMT of type 1 diabetes patients to healthy control subjects. The secondary objective was to determine factors associated with a higher carotid IMT. Methods We conducted a cross-sectional study between March 2009 and October 2013, comprising 127 type 1 diabetes patients and 125 control subjects matched by age, gender and body mass index (BMI). Carotid IMT was measured using semi-automated edge detection software. Results Type 1 diabetes patients had a higher median IMT compared with control subjects (0.538; IQR: 0.500-0.607 vs 0.513 mm; IQR: 0.481-0.557, respectively p?=?0.001). Women with type 1 diabetes had a higher median IMT difference compared to the control group (0.537; IQR: 0.495-0.596 vs 0.502 mm; IQR: 0.472-0.543, respectively p?=?0.003) than did men with type 1 diabetes (0.547; IQR: 0.504-0.613 vs 0.528 mm; IQR: 0.492-0.575, respectively p?=?0.2). Age and diabetes duration had an additive effect on the IMT of type 1 diabetes patients. Multivariate gamma regression model analysis showed that in type 1 diabetes patients, the IMT was associated with age (Exp (?)?=?1.006, p?history of type 2 diabetes (Exp (?)?=?1.044, p?=?0.033), total cholesterol (Exp (?)?=?0.999, p?=?0.001) and creatinine clearance (Exp (?)?=?1.000, p?=?0.043). Conclusions Patients with type 1 diabetes have increased IMT, a marker of subclinical atherosclerosis. The CVD risk may be similar between men and women with type 1 diabetes, suggesting a loss of gender protection. Also, CVD risk may be higher in those with a family history of type 2 diabetes. Prospective studies are needed to confirm the predictive value of these findings and the causal effect between IMT and CVD in patients with type 1 diabetes.

2014-01-01

101

Psychographic and Demographic Profiles of Niche Market Leisure Travelers  

Microsoft Academic Search

This study examined leisure travelers'interests in 11 tourism niche offerings and provided psychographic and demographic profiles of individuals interested in the various niches. Telephone interviews were conducted with 417 respondents in 12 U.S. states. The activities that received the highest interests were outdoor recreation, local fairs and festivals, art and cultural attractions, pioneer and frontier history sites, and cowboy and

Cathy H. C. Hsu; Soo K. Kang; Kara Wolfe

2002-01-01

102

[Diagnosis. History and physical examination].  

PubMed

Family physicians play a key role in the diagnosis and management of patients with osteoarthritis. Diagnosis is mainly clinical and radiological. A complete history should be taken with meticulous physical examination of the joints. The history-taking should aim to detect risk factors and compatible clinical symptoms. Pain characteristics should be identified, distinguishing between mechanical and inflammatory pain, and an exhaustive examination of the joints should be performed, with evaluation of the presence of pain, deformity, mobility restrictions (both active and passive), crepitus, joint effusion, and inflammation. A differential diagnosis should be made with all diseases that affect the joints and/or produce joint stiffness. PMID:24467956

Pérez Martín, Álvaro

2014-01-01

103

Present demographic situation of Czechoslovakia.  

PubMed

Current demographic trends in Czechoslovakia are described. Consideration is given to age distribution, fertility, nuptiality, divorce, mortality, and population growth. The data are presented separately for the two constituent republics. PMID:12158142

Rychtarikova, J

1988-01-01

104

(18F)Fluoro-deoxy-D-glucose uptake of knee joints in the aspect of age-related osteoarthritis: a case-control study  

PubMed Central

Background This study investigated 18F-fluorodeoxyglucose (18F-FDG) uptake at knee joints for determination of metabolic alteration in association with the advance of age and joint degeneration such as osteoarthritis (OA). Methods A total of 166 knees from 83 healthy persons who presented for routine health examination and positron emission tomography-computed tomography (PET/CT) were enrolled in this study. History of knee OA and joint symptoms and signs were reviewed. The maximum standardized uptake values (SUVmax) of cartilage and mean SUV (SUVmean) between the epiphyseal plates of femur and tibia were evaluated at knee joints. Assessment of radiological bony changes was performed using the Kallgren-Lawrence (K/L) grading system with reconstructed CT images of the knee. The joint symptoms and signs were counted and used for diagnosis of clinical and radiological OA of the knee. Results The SUVmean of the knee joints showed a remarkable increase with aging in females (r?=?0.503, p?history of OA (p?joint and the intra-articular SUVmax showed higher values in clinical and radiological OA than in normal joints (p?Joint-SUVmean showed significant correlation with OA severity graded according to K/L score (p?joints, indicating OA in correlation with the joint-SUVmean (p?=?0.01). Conclusions The increasing 18F-FDG uptakes of knee joints showed agreement with aging in females and clinical and radiological knee OA, indicating that the metabolic alterations were consistent with diagnosis and demographic aspect of OA as a surrogate marker for degeneration of the knee in association with aging.

2013-01-01

105

Spontaneous and induced demographic change.  

PubMed

When some scholars from abroad analyze the role of family planning policies in developing countries in changes in the fertility rate, they differentiate 2 categories of change: one is "developmental change in the fertility rate" and the other is "induced change in the fertility rate". Professor Tian Xinyuan, of American nationality, quotes this concept in his analysis of changes in China's fertility rate, and believes that changes in China's fertility rate belong to fairly successful "induced change in fertility behavior". The author agrees with this differentiation, and feels that there is a need to incorporate this kind of differentiation in all analysis of the characteristics and mechanism of demographic change in China. Due to the inclusion of a set of intervening social variables, in fact demographic change in all countries has already evolved the 2 fundamental types of demographic change, spontaneous and induced. However, until now, the authors have not seen a systematic discussion of the differences and the relationship between these 2 types of demographic change. This paper attempts to make some theoretical investigations into the above, and firmly believes that this has definite significance for enriching theories of demographic change and guiding China's family planning practices. PMID:12343855

Song, R L

1991-01-01

106

The Local Cluster Substructure Survey (LoCuSS): I. Joint KPNO/Spitzer/Herschel/Subaru Study of the Star Formation & Assembly Histories of Massive Clusters  

NASA Astrophysics Data System (ADS)

LoCuSS (Local Cluster Substructure Survey) is a systematic multi-wavelength survey of 100 X-ray luminous galaxy clusters at z=0.2 to study the impact of the hierarchical assembly history of the clusters on the star formation histories of the cluster galaxies. Importantly, we are using gravitational lensing to measure cluster mass and substructure - we are therefore able to test the assumptions necessary in other studies to connect baryonic observables with cluster mass. Here we propose a comprehensive near-IR study of the stellar mass content of a sub-set of 32 LoCuSS clusters for which we have Subaru/Suprime-CAM weak lensing mass maps, panoramic Spitzer/MIPS 24(micron) images, and approved GALEX FUV/NUV and Herschel/PACS 100 and 160(micron) images. The proposed J/K-band observations will enable us to measure the stellar mass content of the clusters out to the virial radius, determine whether 24(micron) Spitzer sources are cluster members, and estimate the stellar mass of the 24(micron) cluster population. (We are also submitting a companion CTIO- 4m/ISPI proposal to observe the central 10'×10' area of 12 southern LoCuSS clusters, expanding the data set to explore K-band light as a probe of cluster mass and substructure.)

Egami, Eiichi; Smith, Graham P.; Haines, Chris P.; Takada, Masahiro; Okabe, Noboru; Umetsu, Keiichi; Ellis, Richard S.; Richard, Johan; Kneib, Jean-Paul; Carlstrom, John

2008-08-01

107

Demographics in Astronomy and Astrophysics  

NASA Astrophysics Data System (ADS)

Astronomy has been undergoing a significant demographic shift over the last several decades, as shown by data presented in the 2000 National Research Council (NRC) report "Federal Funding of Astronomical Research," and the 2010 NRC report, "New Worlds, New Horizons in Astronomy and Astrophysics." For example, the number of advertised postdoctoral positions in astronomy has increased much more rapldly than the number of faculty positions, contributing to a holding pattern of early-career astronomers in multiple postdoctoral positions. This talk will summarize some of the current demographic trends in astronomy, including information about gender and ethnic diversity, and describe some of the possible implications for the future. I thank the members of the Astro2010 Demographics Study Group, as well as numerous white-paper contributors to Astro2010, for providing data and analyses.

Ulvestad, James S.

2011-05-01

108

Incidence and Demographics of Childhood Ptosis  

PubMed Central

Purpose To report the incidence and demographics of childhood ptosis diagnosed over a 40-year period in a well-defined population. Design Retrospective, population-based cohort study. Participants Patients (< 19 years) diagnosed with childhood ptosis as residents of Olmsted County, Minnesota, from January 1, 1965, through December 31, 2004 Methods The medical records of all potential patients identified by the Rochester Epidemiology Project were reviewed. Main Outcome Measures Calculated annual age- and sex-specific incidence rates and demographic information. Results A total of 107 children were diagnosed with ptosis during the 40-year period, yielding an incidence of 7.9/100,000 < 19 years (95% confidence interval [CI]: 6.4-9.5) of age. Ninety-six (89.7%) of the 107 were congenital in onset, 81 (75%) of which had simple congenital ptosis, yielding a birth prevalence of 1 in 842 births. A family history of childhood ptosis was present in twelve percent of queried patients with simple congenital ptosis. Three (4%) of the simple congenital ptosis cases were bilateral and 55 (68%) of the unilateral cases involved the left upper eyelid (95% CI: 57%-78%, p<0.001). Conclusion Childhood ptosis was diagnosed in 7.9 per 100,000 patients less than 19 years (95% CI: 6.4-9.5). Simple congenital ptosis was the most prevalent form, occurring in 1 in 842 births, and significantly more likely to involve the left side.

Griepentrog, Gregory J.; Diehl, Nancy; Mohney, Brian G.

2012-01-01

109

Joint effects of density and a growth inhibitor on the life history and population growth rate of the midge Chironomus riparius.  

PubMed

Results of previous laboratory studies suggest that high population density often buffers the effects of chemical stressors that predominately increase mortality. Mortality stressors act to release more resources for the survivors and, therefore, produce less-than-additive effects. By contrast, growth stressors are expected to have opposite results or more-than-additive effects. We investigated the effects of a growth inhibitor (lufenuron) on larval growth and survival of Chironomus riparius and examined its joint effects with density on population growth rate (PGR). Exposure to 60 microg/kg sediment or greater inhibited larval growth, and exposure to 88 microg/kg or greater often resulted in mortality before reaching emergence. The effects of lufenuron, however, differed with population density. At 88 microg/kg, mortalities and, to a lesser extent, reduced fecundity resulted in a reduction in PGR at low density. Conversely, when populations were initiated at high density, PGR was similar to that of controls, because the few survivors reached maturity sooner and started producing offspring earlier. The effect of density as a growth stressor therefore was stronger than the effect of lufenuron, which had effects similar to those of a mortality stressor and produced less-than-additive effects. Long-term studies under field conditions, however, are needed before less-than-additive effects are considered to be the norm. PMID:16110992

Hooper, Helen L; Sibly, Richard M; Hutchinson, Thomas H; Maund, Stephen J

2005-05-01

110

38 CFR 4.66 - Sacroiliac joint.  

Code of Federal Regulations, 2012 CFR

...palpation and percussion over these joints, loss of normal quickness...objective evidence of damage to the joint, and history of trauma sufficiently...strong and practically immovable joint is required. There should be...and the various symptoms of pain and paralysis attributable...

2012-07-01

111

The pre-history of demographic regions in traditional Europe.  

PubMed

The origins of regional variations observed in the household formation systems of rural Europe in the preindustrial era are explored. The author notes that recently exploited census-type data sources concerning Byzantine Greece, early Renaissance Italy, and late medieval England have made it possible to argue that the broad regional variations established at the eve of industrialization are in fact discernible from a much earlier era. The available data on household size and type are also reviewed, with a focus on English data. (SUMMARY IN FRE AND GER) PMID:12282124

Poos, L R

1986-01-01

112

Inferring the demographic history of the Adriatic Flexopecten complex  

Microsoft Academic Search

Phylogenetic analysis of DNA sequences can be a useful tool in taxonomical studies, which has important implications in terms of species traceability. The aim of our study is to solve the controversy regarding the taxonomical status of the Flexopecten group, which includes two putative sister species (F. glaber and F. proteus) that co-occur in the Adriatic Sea and are clearly

J. M. Pujolar; T. Mar?eta; C. Saavedra; M. Bressan; L. Zane

2010-01-01

113

Changing Demographics: Challenges for Educators.  

ERIC Educational Resources Information Center

This paper identifies demographic changes in the areas of poverty, single-parent families, teenage pregnancy, and educational achievement, with emphasis on increased vulnerability of minority populations. It also notes related challenges to the educational system in personnel recruitment and preparation, effective delivery of educational services…

Williams, Betty Fry

1992-01-01

114

Demographic Factors Affecting Faculty Salary.  

ERIC Educational Resources Information Center

Specific demographic attributes that influence salary at institutions of higher education were studied through data from 420 faculty members at 9 institutions. Results suggested that experience, publication rates, time at the institution, and possession of a terminal degree affected salary levels. The presence of salary compression was noted. (SLD)

Webster, Allen L.

1995-01-01

115

DEMOGRAPHIC DATA FOR CENSUS 2000  

EPA Science Inventory

This data layer represents Census 2000 demographic data derived from the PL94-171 redistricting files and SF3. Census geographic entities include blocks, blockgroups and tracts. Tiger line files are the source of the geometry representing the Census blocks. Attributes include ...

116

Demographic Challenges in America's Future.  

ERIC Educational Resources Information Center

This document examines trends in the United States population since World War II, and projects a scenario of how demographic and economic phenomena may evolve over the next several decades. The report is divided into five sections. Section 1 introduces the volume and discusses generally some of the effects of the nation's transition to zero…

Butz, William P.; And Others

117

Capulin Volcano National Monument, An Administrative History.  

National Technical Information Service (NTIS)

The region surrounding Capulin Volcano National Monument has an extensive history of cooperation, conflict, and adaptation. Research reveals Capulin's story of geologic formation, human habitation fluxes, and numerous demographic changes. In 1916, the vol...

J. Huner S. Lael

2003-01-01

118

Men in the demographic transition  

Microsoft Academic Search

Women’s fertility is the focus of most demographic analyses, for in most mammals, and in many preindustrial societies, variance\\u000a in male fertility, while an interesting biological phenomenon, is irrelevant. Yet in monogamous societies, the reproductive\\u000a ecology of men, as well as that of women, is important is creating reproductive patterns. In nineteenth-century Sweden, the\\u000a focus of this study, male reproductive

Bobbi S. Low

1994-01-01

119

Joint Control for Dummies*: An Elaboration of Lowenkron's Model of Joint (Stimulus) Control  

PubMed Central

The following paper describes Lowenkron's model of joint (stimulus) control. Joint control is described as a means of accounting for performances, especially generalized performances, for which a history of contingency control does not provide an adequate account. Examples are provided to illustrate instances in which joint control may facilitate performance of a task.

Sidener, David W

2006-01-01

120

Joint Control for Dummies: An Elaboration of Lowenkron's Model of Joint (Stimulus) Control  

ERIC Educational Resources Information Center

The following paper describes Lowenkron's model of joint (stimulus) control. Joint control is described as a means of accounting for performances, especially generalized performances, for which a history of contingency control does not provide an adequate account. Examples are provided to illustrate instances in which joint control may facilitate…

Sidener, David W.

2006-01-01

121

Recent developments in the tribology of artificial joints  

Microsoft Academic Search

A history of the tribological development of artificial joints compares how these are lubricated with the mechanisms involved in human joints. It is concluded that while healthy human joints are lubricated by fluid film action, all current artificial joints at best are lubricated by mixed lubrication and hence wear is taking place throughout the life of the prosthesis. A new

A. Unsworth

1995-01-01

122

Demographic features of subjects with congenital glaucoma  

PubMed Central

Context: Congenital glaucoma is a potentially blinding ocular disease of the childhood. Identification of the possible associated risk factors and may be helpful for prevention or early detection of this public health problem. Aims: To demonstrate the demographic features of congenital glaucoma subjects. Setting and Design: The charts of congenital glaucoma patients referred to Tamcelik Glaucoma Center were retrospectively reviewed through the dates of 2000 and 2013. Materials and Methods: Analyzed data included diagnosis, age at first presentation, symptoms at first presentation, laterality of the disease, sex, presence of consanguinity, family history of congenital glaucoma, maturity of the fetus at delivery, and maternal age at conception. Statistical Analysis Used: Statistical Package for Social Sciences (SPSS) version 19.0 by IBM (SPSS Inc, Chicago, Illinois, USA) was used to compare the mean of continuous variables with Student's t-test and analysis of variance (ANOVA) and ?2 test was used to test differences in proportions of categorical variables. Results: The data of 600 eyes of 311 patients were analyzed. The distribution of primary and secondary congenital glaucoma among the patients were 63.3% (n = 197) and 36.7% (n = 114), respectively. Of the 311 patients, 57.2% (n = 178) were male and 42.8% (n = 133) were female. The overall frequency of bilateral disease was 92.3% (n = 287). Overall rate of consanguinity and positive family history was 45.3% (n = 141) and 21.2% (n = 66), respectively. Conclusions: Bilateral disease in this study was more common than previously reported studies. Positive family history was more frequent in primary congenital glaucoma although not statistically significant.

Tamcelik, Nevbahar; Atalay, Eray; Bolukbasi, Selim; Capar, Olgu; Ozkok, Ahmet

2014-01-01

123

China's Demographic Limits to Economic Growth.  

National Technical Information Service (NTIS)

China's demographic transition will create great difficulty in continuing the scale of economic development seen over the last 30 years. This difficulty will be experienced through the costs of the demographic detour, which began during the Great Leap For...

D. M. Truesdell

2012-01-01

124

Biosocial models: Can demographers ignore them?  

Microsoft Academic Search

Social demographers must take seriously the challenge to dominant theoretical paradigms that is posed by biosocial models. Accumulating empirical evidence documents the significant contribution of biological variables to the determination of social behaviors, including demographic behaviors. The simplest biosocial models may prove inadequate in social demographic research. More appropriate models may need to allow for causal relationships between biological and

John B. Casterline

1995-01-01

125

[Recent demographic change in the French Pyrenees].  

PubMed

Results from the 1990 French census are used to analyze recent demographic trends in the French Pyrenees. A trend toward demographic aging and demographic-related problems in the region's small towns is noted. The authors find that a decline in traditional industries is partially counteracted by a growth in tourism in selected centers. (SUMMARY IN ENG AND SPA) PMID:12318342

Desbordes, F; Laborie, J

1991-01-01

126

The abnormal proximal tibiofibular joint.  

PubMed

Abnormalities of the proximal tibiofibular joint are infrequently encountered. Mostly instability occurs as a result of trauma. Four types of instability are distinguished: subluxation, anterolateral, posteromedial and superior dislocation. Four radiological methods designed to visualize abnormalities of the proximal tibiofibular joint are discussed. Special notice is given to the clinical relevance of a new method. Instability was demonstrated in 19 patients; 16 of these were treated by an operation. History, data obtained by physical examination and ways of treatment are discussed. PMID:6703874

Veth, R P; Kingma, L M; Nielsen, H K

1984-01-01

127

Demographic estimation methods for plants with dormancy  

USGS Publications Warehouse

Demographic studies in plants appear simple because unlike animals, plants do not run away. Plant individuals can be marked with, e.g., plastic tags, but often the coordinates of an individual may be sufficient to identify it. Vascular plants in temperate latitudes have a pronounced seasonal life-cycle, so most plant demographers survey their study plots once a year often during or shortly after flowering. Life-states are pervasive in plants, hence the results of a demographic study for an individual can be summarized in a familiar encounter history, such as OVFVVF000. A zero means that an individual was not seen in a year and a letter denotes its state for years when it was seen aboveground. V and F here stand for vegetative and flowering states, respectively. Probabilities of survival and state transitions can then be obtained by mere counting. Problems arise when there is an unobservable dormant state, I.e., when plants may stay belowground for one or more growing seasons. Encounter histories such as OVFOOF000 may then occur where the meaning of zeroes becomes ambiguous. A zero can either mean a dead or a dormant plant. Various ad hoc methods in wide use among plant ecologists have made strong assumptions about when a zero should be equated to a dormant individual. These methods have never been compared among each other. In our talk and in Kery et al. (submitted), we show that these ad hoc estimators provide spurious estimates of survival and should not be used. In contrast, if detection probabilities for aboveground plants are known or can be estimated, capture-recapture (CR) models can be used to estimate probabilities of survival and state-transitions and the fraction of the population that is dormant. We have used this approach in two studies of terrestrial orchids, Cleistes bifaria (Kery et aI., submitted) and Cypripedium reginae (Kery & Gregg, submitted) in West Virginia, U.S.A. For Cleistes, our data comprised one population with a total of 620 marked ramets over 10 years, and for Cypripedium, two populations with 98 and 258 marked ramets over 11 years. We chose the ramet (= single stem or shoot) as the demographic unit of our study since there was no way distinguishing among genets (genet = genetical individual, I.e., the 'individual' that animal ecologists are mostly concerned with). This will introduce some non-independence into the data, which can nevertheless be dealt with easily by correcting variances for overdispersion. Using ramets instead of genets has the further advantage that individuals can be assigned to a state such as flowering or vegetative in an unambiguous manner. This is not possible when genets are the demographic units. In all three populations, auxiliary data was available to show that detection probability of aboveground plants was > 0.995. We fitted multistate models in program MARK by specifying three states (D, V, F), even though the dormant state D does not occur in the encounter histories. Detection probability is fixed at 1 for the vegetative (V) and the flowering state (F) and at zero for the dormant state (D). Rates of survival and of state transitions as well as slopes of covariate relationships can be estimated and LRT or the AIC machinery be used to select among models. To estimate the fraction of the population in the unobservable dormant state, the encounter histories are collapsed to 0 (plant not observed aboveground) and 1 (plant observed aboveground). The Cormack-Jolly-Seber model without constraints on detection probability is used to estimate detection probability, the complement of which is the estimated fraction of the population in the dormant state. Parameter identifiability is an important issue in multi state models. We used the Catchpole-Morgan-Freeman approach to determine which parameters are estimable in principle in our multi state models. Most of 15 tested models were indeed estimable with the notable exception of the most ge

Kery, M.; Gregg, K. B.

2004-01-01

128

India's demographic change: opportunities and challenges.  

PubMed

This paper discusses emerging demographic patterns and its opportunities and challenges for India. It investigates the specificities in the demographic transition in terms of various demographic parameters and the lack of homogeneity in the transition across states in the country. It presents some opportunities that can arise from having demographic changes, particularly the demographic dividend and interstate migration to overcome labor shortage in some parts. At the same time, there are serious challenges in the form of enhancing human capital development, addressing the issue of skewed sex ratio, and the possible rise in social and political unrest and conflict. PMID:21798938

James, K S

2011-07-29

129

Defense Implications of Demographic Trends.  

National Technical Information Service (NTIS)

Because of its perceived association with national power- economic, military, and even ideological-population has weighed heavily on the minds of state leaders throughout history. Romanian dictator Nicolae Ceausescu once declared, 'Anyone who avoids havin...

J. D. Sciubba

2008-01-01

130

Joint Problems  

MedlinePLUS

... ankles and toes. Other types of arthritis include gout or pseudogout. Sometimes, there is a mechanical problem ... for more information on osteoarthritis, rheumatoid arthritis and gout. How Common are Joint Problems? Osteoarthritis, which affects ...

131

Molecular evidence for a recent demographic expansion in the puma (Puma concolor) (Mammalia, Felidae)  

PubMed Central

The puma is an iconic predator that ranges throughout the Americas, occupying diverse habitats. Previous phylogeographic analyses have revealed that it exhibits moderate levels of genetic structure across its range, with few of the classically recognized subspecies being supported as distinct demographic units. Moreover, most of the species’ molecular diversity was found to be in South America. To further investigate the phylogeographic structure and demographic history of pumas we analyzed mtDNA sequences from 186 individuals sampled throughout their range, with emphasis on South America. Our objectives were to refine the phylogeographic assessment within South America and to investigate the demographic history of pumas using a coalescent approach. Our results extend previous phylogeographic findings, reassessing the delimitation of historical population units in South America and demonstrating that this species experienced a considerable demographic expansion in the Holocene, ca. 8,000 years ago. Our analyses indicate that this expansion occurred in South America, prior to the hypothesized re-colonization of North America, which was therefore inferred to be even more recent. The estimated demographic history supports the interpretation that pumas suffered a severe demographic decline in the Late Pleistocene throughout their distribution, followed by population expansion and re-colonization of the range, initiating from South America.

Matte, Eunice M.; Castilho, Camila S.; Miotto, Renata A.; Sana, Denis A.; Johnson, Warren E.; O'Brien, Stephen J.; de Freitas, Thales R. O.; Eizirik, Eduardo

2013-01-01

132

Molecular evidence for a recent demographic expansion in the puma (Puma concolor) (Mammalia, Felidae).  

PubMed

The puma is an iconic predator that ranges throughout the Americas, occupying diverse habitats. Previous phylogeographic analyses have revealed that it exhibits moderate levels of genetic structure across its range, with few of the classically recognized subspecies being supported as distinct demographic units. Moreover, most of the species' molecular diversity was found to be in South America. To further investigate the phylogeographic structure and demographic history of pumas we analyzed mtDNA sequences from 186 individuals sampled throughout their range, with emphasis on South America. Our objectives were to refine the phylogeographic assessment within South America and to investigate the demographic history of pumas using a coalescent approach. Our results extend previous phylogeographic findings, reassessing the delimitation of historical population units in South America and demonstrating that this species experienced a considerable demographic expansion in the Holocene, ca. 8,000 years ago. Our analyses indicate that this expansion occurred in South America, prior to the hypothesized re-colonization of North America, which was therefore inferred to be even more recent. The estimated demographic history supports the interpretation that pumas suffered a severe demographic decline in the Late Pleistocene throughout their distribution, followed by population expansion and re-colonization of the range, initiating from South America. PMID:24385863

Matte, Eunice M; Castilho, Camila S; Miotto, Renata A; Sana, Denis A; Johnson, Warren E; O'Brien, Stephen J; de Freitas, Thales R O; Eizirik, Eduardo

2013-12-01

133

Demographic features of patients seeking cosmetic surgery.  

PubMed

The demographic features of 415 patients seeking cosmetic surgery were investigated from a psychiatric point of view. Of the 415 patients, 198 (47.7%) were found to have mental disorders according to ICD-10 including: 17 with schizophrenia, 20 with other persistent delusional disorders, 33 with depressive episode, 47 with neurotic disorders, 42 with hypochondriacal disorder, five with paranoid personality disorder and 14 with histrionic personality disorder. The rate of subjects with poor social adjustment was 56.0%. It was noteworthy that such a considerable number of patients with mental disorders or with poor social adjustment had sought cosmetic surgery. Distinct gender differences were found: male subjects were characterized to have a greater number of mental disorders, especially dysmorphophobia (other persistent delusional disorders plus hypochondriacal disorder) and showed the narrow age range between teenage and young adult age when they were preoccupied with their 'deformity', and poor social function. A history of frequent operations was not considered to be an indicator for mental abnormality. The diagnostic issue in dysmorphophobia is briefly described. PMID:9681579

Ishigooka, J; Iwao, M; Suzuki, M; Fukuyama, Y; Murasaki, M; Miura, S

1998-06-01

134

The Epidemiology and Demographics of Hip Dysplasia  

PubMed Central

The etiology of developmental dysplasia of the hip (DDH) is unknown. There are many insights, however, from epidemiologic/demographic information. A systematic medical literature review regarding DDH was performed. There is a predominance of left-sided (64.0%) and unilateral disease (63.4%). The incidence per 1000 live births ranges from 0.06 in Africans in Africa to 76.1 in Native Americans. There is significant variability in incidence within each racial group by geographic location. The incidence of clinical neonatal hip instability at birth ranges from 0.4 in Africans to 61.7 in Polish Caucasians. Predictors of DDH are breech presentation, positive family history, and gender (female). Children born premature, with low birth weights, or to multifetal pregnancies are somewhat protected from DDH. Certain HLA A, B, and D types demonstrate an increase in DDH. Chromosome 17q21 is strongly associated with DDH. Ligamentous laxity and abnormalities in collagen metabolism, estrogen metabolism, and pregnancy-associated pelvic instability are well-described associations with DDH. Many studies demonstrate an increase of DDH in the winter, both in the northern and southern hemispheres. Swaddling is strongly associated with DDH. Amniocentesis, premature labor, and massive radiation exposure may increase the risk of DDH. Associated conditions are congenital muscular torticollis and congenital foot deformities. The opposite hip is frequently abnormal when using rigorous radiographic assessments. The role of acetabular dysplasia and adult hip osteoarthritis is complex. Archeological studies demonstrate that the epidemiology of DDH may be changing.

Loder, Randall T.; Skopelja, Elaine N.

2011-01-01

135

An Aging World--demographics and challenges.  

PubMed

The world has seen enormous changes over the past century, including historically unprecedented declines in mortality rates and increases in population, followed by equally unprecedented declines in fertility rates. This century will see a new set of demographic challenges, including a mix of falling fertility rates alongside persisting worldwide population growth, and the subsequent aging of populations in both developing and developed countries. The 20th century was the century of population growth; the 21st century will go into the history books as the century of aging. A holistic approach to this new challenge of the 21st century will necessitate a quantum leap in multidisciplinary and internationally coordinated research efforts, supported by a new partnership between industry and governments, philanthropic and international organizations. This collaboration we hope will enrich us with a better understanding of healthy aging, permit us to help to improve quality of life, prevent the preventable, and postpone and decrease the pain and suffering of the inevitable. PMID:18224537

Lunenfeld, Bruno

2008-01-01

136

The prevalence of chondrocalcinosis (CC) of the acromioclavicular (AC) joint on chest radiographs and correlation with calcium pyrophosphate dihydrate (CPPD) crystal deposition disease.  

PubMed

Digital imaging combined with picture archiving and communication system (PACS) access allows detailed image retrieval and magnification. Calcium pyrophosphate dihydrate (CPPD) crystals preferentially deposit in fibrocartilages, the cartilage of the acromioclavicular (AC) joint being one such structure. We sought to determine if examination of the AC joints on magnified PACS imaging of chest films would be useful in identifying chondrocalcinosis (CC). Retrospective radiographic readings and chart reviews involving 1,920 patients aged 50 or more who had routine outpatient chest radiographs over a 4-month period were performed. Knee radiographs were available for comparison in 489 patients. Medical records were reviewed to abstract demographics, chest film reports, and diagnoses. AC joint CC was identified in 1.1 % (21/1,920) of consecutive chest films. Patients with AC joint CC were 75 years of age versus 65.4 in those without CC (p?joint CC, and of these, five also had knee CC (83 %). Of the 483 without AC joint CC, 62 (12 %) had knee CC (p?=?0.002). Patients with AC joint CC were more likely to have a recorded history of CPPD crystal deposition disease than those without AC joint CC (14 versus 1 %, p?=?0.0017). The prevalence of AC joint CC increases with age and is associated with knee CC. A finding of AC joint CC should heighten suspicion of pseudogout or secondary osteoarthritis in appropriate clinical settings and, in a young patient, should alert the clinician to the possibility of an associated metabolic condition. PMID:23609408

Parperis, Konstantinos; Carrera, Guillermo; Baynes, Keith; Mautz, Alan; Dubois, Melissa; Cerniglia, Ross; Ryan, Lawrence M

2013-09-01

137

Degenerative Joint Disease in Female Ballet Dancers  

Microsoft Academic Search

The relationship between long-term ballet dancing and eventual arthrosis of the hip, ankle, subtalar, and first metatarsophalangeal joint was examined in 19 former professional female dancers, aged 50 to 70 years. The dancers were compared with pair-matched controls. All 38 women underwent medical history taking, clinical ex amination, and roentgenography of the joints studied. The roentgenographs were independently judged by

C. Niek van Dijk; Liesbeth S. L. Lim; Alina Poortman; Ernst H. Strübbe; Rene K. Marti

1995-01-01

138

Operation Sea Lion: A Joint Critical Analysis.  

National Technical Information Service (NTIS)

Military history contains many lessons from which the warfighting doctrine of the individual services, as well as joint doctrine, is derived. World War II stands as one of the major contributors of valuable lessons learned. From a joint and combined warfi...

R. McCanne G. D. Olson D. E. Teicher

2002-01-01

139

Selection Against Demographic Stochasticity in Age-Structured Populations  

PubMed Central

It has been shown that differences in fecundity variance can influence the probability of invasion of a genotype in a population; i.e., a genotype with lower variance in offspring number can be favored in finite populations even if it has a somewhat lower mean fitness than a competitor. In this article, Gillespie's results are extended to population genetic systems with explicit age structure, where the demographic variance (variance in growth rate) calculated in the work of Engen and colleagues is used as a generalization of “variance in offspring number” to predict the interaction between deterministic and random forces driving change in allele frequency. By calculating the variance from the life-history parameters, it is shown that selection against variance in the growth rate will favor a genotypes with lower stochasticity in age-specific survival and fertility rates. A diffusion approximation for selection and drift in a population with two genotypes with different life-history matrices (and therefore different mean growth rates and demographic variances) is derived and shown to be consistent with individual-based simulations. It is also argued that for finite populations, perturbation analyses of both the mean and the variance in growth rate may be necessary to determine the sensitivity of fitness to changes in the life-history parameters.

Shpak, Max

2007-01-01

140

The Importance of Demographic Data in Astronomy  

NASA Astrophysics Data System (ADS)

The most effective astronomical workforce will be one that comprises a diverse and inclusive community. The “New Worlds, New Horizons in Astronomy and Astrophysics” Decadal Survey, with input from its Infrastructure Study Group on Demographics, provided an overview of recent demographic trends. Demographics in astronomy have undergone significant changes over the past two generations in several, but not all, categories. Maintaining records of demographics regarding age, gender, and minority status, as well as trends by discipline and career choices, is vital in planning for the future training and employment of astronomers.

Elmegreen, Debra M.

2014-01-01

141

Demographic studies of extrasolar planets  

NASA Astrophysics Data System (ADS)

Uncovering the demographics of extrasolar planets is crucial to understanding the processes of their formation and evolution. In this thesis, we present four studies that contribute to this end, three of which relate to NASA's Kepler mission, which has revolutionized the field of exoplanets in the last few years. In the pre-Kepler study, we investigate a sample of exoplanet spin-orbit measurements---measurements of the inclination of a planet's orbit relative to the spin axis of its host star---to determine whether a dominant planet migration channel can be identified, and at what confidence. Applying methods of Bayesian model comparison to distinguish between the predictions of several different migration models, we find that the data strongly favor a two-mode migration scenario combining planet-planet scattering and disk migration over a single-mode Kozai migration scenario. While we test only the predictions of particular Kozai and scattering migration models in this work, these methods may be used to test the predictions of any other spin-orbit misaligning mechanism. We then present two studies addressing astrophysical false positives in Kepler data. The Kepler mission has identified thousands of transiting planet candidates, and only relatively few have yet been dynamically confirmed as bona fide planets, with only a handful more even conceivably amenable to future dynamical confirmation. As a result, the ability to draw detailed conclusions about the diversity of exoplanet systems from Kepler detections relies critically on understanding the probability that any individual candidate might be a false positive. We show that a typical a priori false positive probability for a well-vetted Kepler candidate is only about 5-10%, enabling confidence in demographic studies that treat candidates as true planets. We also present a detailed procedure that can be used to securely and efficiently validate any individual transit candidate using detailed information of the signal's shape as well as follow-up observations, if available. Finally, we calculate an empirical, non-parametric estimate of the shape of the radius distribution of small planets with periods less than 90 days orbiting cool (less than 4000K) dwarf stars in the Kepler catalog. This effort reveals several notable features of the distribution, in particular a maximum in the radius function around 1-1.25 Earth radii and a steep drop-off in the distribution larger than 2 Earth radii. Even more importantly, the methods presented in this work can be applied to a broader subsample of Kepler targets to understand how the radius function of planets changes across different types of host stars.

Morton, Timothy

142

Levels and trends of demographic indices in southern rural Mozambique: evidence from demographic surveillance in Manhi?a district  

PubMed Central

Background In Mozambique most of demographic data are obtained using census or sample survey including indirect estimations. A method of collecting longitudinal demographic data was introduced in southern Mozambique since 1996 (DSS -Demographic Surveillance System in Manhiça district, Maputo province), but the extent to which it yields demographic measures that are typical of southern rural Mozambique has not been evaluated yet. Methods Data from the DSS were used to estimate the levels and trends of fertility, mortality and migration in Manhiça, between 1998 and 2005. The estimates from Manhiça were compared with estimates from Maputo province using the 1997 National census and 1997 Demographic and Health Survey (DHS). The DHS data were used to estimate levels and trends of adult mortality using the siblings' histories and the orphanhood methods. Results The populations in Manhiça and in Maputo province are young (44% <15 years in Manhiça and 42% in Maputo); with reduced adult males when compared to females (all ages sex ratio of 78.7 in Manhiça and 89 in Maputo). Fertility in Manhiça is at a similar level as in Maputo province and has remained around 5 children per woman, during the eight years of surveillance in Manhiça. Although the infant mortality rate (IMR) in Mozambique has decreased during the last two decades (from 148 deaths per 1000 live births in 1980 to 101 in 2003), it has remained stable around 80 in Manhiça during the surveillance period. Adult mortality has increased both in Manhiça (probability of dying from ages 15 to 60 increased from 0.4 in 1998 to 0.6 in 2005 in Manhiça, from 0.3 in 1992 to 0.4 in 1997 in Maputo province and from 0.1 in 1980 to 0.6 in 2000 in Mozambique). Consequently, the life expectancy decreased from 53 to 46 in Manhiça and from 42 years in 1997 to 38 in 2004 in Mozambique. Migration is high in Manhiça but tends to stabilise after the movements of resettlement that followed the end of the civil war in 1992. Conclusion The population under demographic surveillance in Manhiça district presents characteristics that are typical of southern rural Mozambique, with predominance of young people and reduction of adult males. Labour migration and excess adult male mortality are the major factors for the reduction of adult males. Mortality is high and only infant mortality has started to stabilise while adult mortality has increased, and as consequence, life expectancy has decreased. The Manhiça DSS is an adequate tool to report demographic measures for southern rural Mozambique.

Nhacolo, Ariel Q; Nhalungo, Delino A; Sacoor, Charfudin N; Aponte, John J; Thompson, Ricardo; Alonso, Pedro

2006-01-01

143

Poweshiek History Preservation Project  

NSDL National Science Digital Library

The Poweshiek History Preservation Project is a joint effort between the Grinnell College Libraries and the Drake Community Library to preserve the history of the people and places of Poweshiek County. Over the years, dozens of community members have brought in letters, photographs, scrapbooks, ledgers, and other documents that tell the area's history. This site contains over 120 items, including photos of roadwork construction, local churches, museums, and portraits of prominent community members. Most of the items here date from the late 19th and early 20th century and they provide a remarkable look into the changes throughout the community during this period. Additionally, the site contains several oral histories from locals who have lived here for decades. Visitors can search through the offering by date, type, or geographic coverage.

144

Changing School Demographics: The New Baby Boom.  

ERIC Educational Resources Information Center

This paper addresses the demographic and socioeconomic effects on schools of the "new baby boom," consisting of school-age children of the original "baby boomers." The effects of this second-generation demographic trend include a higher proportion of minority students (since the decline in marriage and birth rates among baby boomers reaching…

Lake, Sara

145

The U.S. Demographic Transition  

Microsoft Academic Search

Between 1800 and 1940 the U.S. went through a dramatic demographic transition. In 1800 the average woman had 7 children, and 94 percent of the population lived in rural areas. By 1940 the average woman birthed just 2 kids, and only 43 percent of populace lived in the country. The question is: What accounted for this shift in the demographic

Jeremy Greenwood; Ananth Seshadri

2002-01-01

146

Life Potential as a Basic Demographic Indicator  

ERIC Educational Resources Information Center

This paper proposes an indicator that integrates life expectancy with the demographic structure of the population for a given society. By doing this, we have a simple indicator of mortality and aging combined, which could be very useful for developed societies. As is widely known, life expectancy at birth is independent of the demographic

Goerlich, Francisco J.; Soler, Angel

2013-01-01

147

Computer History  

NSDL National Science Digital Library

Some Websites Exploring the History of the Personal Computer Wow! What a lot of websites about computer history. Here's a few that I found...Check them out and then, when you get back here, go Take the Quiz . The List of Cool Sites Museum of Computer History The History of Computing Project The Computer Comes Home: A History of Personal Computing Computer History Museum ...

Cannon, Mr.

2005-12-10

148

Joint pain  

Microsoft Academic Search

Joint pain may result from traumas or repeated microtraumas, as in sports injuries. Pain in osteoarthritis starts before any\\u000a objective finding. It has been demonstrated that in the first stages of this disease, pain is due to intraosseous venous engorgement\\u000a for the earlier thickening of the cortical bone under the articular cartilage. The mechanisms of inflammatory pain are more\\u000a complex

Massimo Zoppi; Elisabetta Beneforti

1999-01-01

149

Teaching Family History: Papers from Old Sturbridge Village.  

ERIC Educational Resources Information Center

Essays in this special issue of the "Journal of Family History" focus on the teaching of family history by using artifacts. The articles were written by the staff at Old Sturbridge Village (OSV). The first article discusses how family history is taught at OSV. Students study a real family using demographic information and artifacts such as…

Journal of Family History, 1981

1981-01-01

150

Differentiate or Die: Colleges Need a Clear Niche to Thrive in the Coming Demographic Crisis  

ERIC Educational Resources Information Center

New England higher education is about to experience a decade-long demographic crisis unlike anything in its history. While the crisis will significantly affect all six New England States, it will be most acute in the three northern states, as the competition for qualified high school graduates begins to intensify. The New England states, including…

Handy, Ty J.

2008-01-01

151

Clinical and Demographic Characteristics Help Explain Variations in Pain at the End of Life  

Microsoft Academic Search

The natural history of pain at the end of life is not well understood. The purpose of this study was to estimate the association between clinical and demographic characteristics and pain in persons who received hospice care in the United States. Data for this study were obtained from a national provider of hospice pharmacy services and included information about the

Scott A. Strassels; David K. Blough; David L. Veenstra; Thomas K. Hazlet; Sean D. Sullivan

2008-01-01

152

Demographic analysis as an aid in shark stock assessment and management  

Microsoft Academic Search

The use of demographic analyses incorporating life history information on validated age and growth, reproduction, and natural mortality is proposed to gain insight into the population dynamics of sharks under a variety of scenarios and to assess their vulnerability to varying exploitation rates. This approach provides a useful framework for comparison with other currently used methods of assessment, especially those

Enric Cortés

1998-01-01

153

Average depth of tarsometatarsal joint for trephine arthrodesis.  

PubMed

The trephine arthrodesis technique has been shown to be an effective method for various foot and ankle fusion procedures, with acceptable rates of fusion reported. The tarsometatarsal joints are an excellent example for this procedure because of the joint shape and soft tissue stability. The success of this procedure depends on many factors, but a large consideration is adequate joint resection. A cadaveric study to examine the joint depth of the Lisfranc complex was undertaken, allowing for improved understanding of the resection needed to maintain a stable plantar cortex while removing all apposing joint surfaces. A statistical analysis was then performed to determine the significance of the joint depth to available demographic data. A total of 51 limbs were evaluated for the depth of the first, second, and third metatarsal-cuneiform joints. The average joint depth for the first through third metatarsal-cuneiform joints was 32.3, 26.9, and 23.6 mm, respectively. The plantar cortex depth was less than 2 mm for the first through third metatarsal-cuneiform joints. The correlation between the length of the foot and the joint depth was statistically significant. Subgroups stratified by shoe size were analyzed for differences in joint size and were also statistically significant. A better understanding of the tarsometatarsal joint anatomy would benefit the trephine technique for Lisfranc arthrodesis. PMID:22192856

Ryan, Jay D; Timpano, Eugene D; Brosky, Thomas A

2012-01-01

154

REAP Economic Demographic Model: Technical Description.  

National Technical Information Service (NTIS)

The report describes the structure and data base of a computerized model for projecting localized economic, demographic, and fiscal impacts of new energy developments. The model provides baseline and single or multiple-project impact projections for a 15-...

T. Hertsgaard, S. Murdock, N. Toman, M. Henry, R. Ludtke

1978-01-01

155

Social and Demographic Examination of Fishing Participation.  

National Technical Information Service (NTIS)

The initial section of this report compares selected angling and demographic information from the 1991 and 1996 National Surveys concerning angling in freshwater, saltwater and the Great Lakes areas to determine if changes have occurred during the five-ye...

A. J. Fedler K. A. Leahy

2000-01-01

156

CENTRACT BOUNDARIES AND DEMOGRAPHIC DATABASE AND CVOVERAGE  

EPA Science Inventory

This coverage contains Census Tract boundaries and associated demographic data. "Census tracts are small, relatively permanent statistical subdivisions of a county. Census tracts are delineated for all metropolitan areas (MAs) and other densely populated counties by local c...

157

Demographics and the Changing National Security Environment.  

National Technical Information Service (NTIS)

Demographic factors seldom directly cause conflict between nations. They can, however, exacerbate existing tensions and increase the risk of violent conflict. Long- term fertility trends, urbanization, migration, and changes in the ethnic composition and ...

2000-01-01

158

California Travel Trends and Demographics Study.  

National Technical Information Service (NTIS)

The purpose of the Transportation Trend Analysis and Demographic Projection Study was to analyze past population and travel trends, and project future trends, in order to support the state infrastructure and development planning process. Tasks included: P...

R. Crane A. Valenzuela D. Chatman L. Schweitzer P. J. Wong

2002-01-01

159

Population History and Natural Selection Shape Patterns of Genetic Variation in 132 Genes  

Microsoft Academic Search

Identifying regions of the human genome that have been targets of natural selection will provide important insights into human evolutionary history and may facilitate the identification of complex disease genes. Although the signature that natural selection imparts on DNA sequence variation is difficult to disentangle from the effects of neutral processes such as population demographic history, selective and demographic forces

Joshua M. Akey; Michael A. Eberle; Mark J. Rieder; Christopher S. Carlson; Mark D. Shriver; Deborah A. Nickerson; Leonid Kruglyak

2004-01-01

160

Tuberculosis of contralateral costotransverse joints  

Microsoft Academic Search

We present a case of multifocal tuberculosis of contralateral costo-transverse joints. Even in countries where tuberculosis\\u000a is common, extrapulmonary multifocal infection is uncommon. Furthermore, a bilateral, symmetric distribution is distinctly\\u000a unusual. The index of suspicion for tuberculosis should increase when the patient is from a country where tuberculosis is\\u000a endemic or when a history of AIDS is present.

S. M. Levine; E. B. Marianacci; S. V. Kattapuram

1997-01-01

161

Open versus minimally invasive sacroiliac joint fusion: a multi-center comparison of perioperative measures and clinical outcomes  

PubMed Central

Background Sacroiliac (SI) joint pain is an under diagnosed source of low back pain due in part to lack of visible pathology on radiographs and symptoms mimicking other back-related disorders. Open SI joint fusion has been performed since the 1920s. This technique has fallen out of favor with the introduction of minimally invasive options. To date there has been no direct comparison between open and MIS SI joint fusion. Methods We conducted a multi-center, retrospective comparative cohort study of patients who underwent SI joint fusion using either an open surgical (OS) technique using a combination of screws and cages or a minimally invasive surgical (MIS) technique with a series of titanium plasma spray (TPS) coated triangular implants. Operative measures including surgical operating time, length of hospitalization and estimated blood loss (EBL) were collected along with demographics and medical history, surgical complications, and 12- and 24-month pain scores. Improvements in pain were compared after matching for age and gender and controlling for a history of lumbar spine fusion using repeated measures analysis of variance. Results Data were available for 263 patients treated by 7 surgeons; 149 patients treated with OS and 114 treated with MIS SI joint fusion. Compared to OS patients, MIS patients were on average 10 years older (mean age 57 vs. 46) and 69% of all patients were female. MIS operative measures of EBL, operating time and length of hospitalization were significantly lower than open surgery (p?history of prior lumbar spinal fusion, postoperative pain scores were on average 3.0 points (95% CI 2.1 – 4.0) lower in MIS vs. OS (rANOVA p?joint fusion showed postoperative improvements in pain score. Compared to OS patients, patients who underwent MIS SI joint fusion had significantly greater pain relief and more favorable perioperative surgical measures.

2013-01-01

162

Identifying image preferences based on demographic attributes  

NASA Astrophysics Data System (ADS)

The intent of this study is to determine what sorts of images are considered more interesting by which demographic groups. Specifically, we attempt to identify images whose interestingness ratings are influenced by the demographic attribute of the viewer's gender. To that end, we use the data from an experiment where 18 participants (9 women and 9 men) rated several hundred images based on "visual interest" or preferences in viewing images. The images were selected to represent the consumer "photo-space" - typical categories of subject matter found in consumer photo collections. They were annotated using perceptual and semantic descriptors. In analyzing the image interestingness ratings, we apply a multivariate procedure known as forced classification, a feature of dual scaling, a discrete analogue of principal components analysis (similar to correspondence analysis). This particular analysis of ratings (i.e., ordered-choice or Likert) data enables the investigator to emphasize the effect of a specific item or collection of items. We focus on the influence of the demographic item of gender on the analysis, so that the solutions are essentially confined to subspaces spanned by the emphasized item. Using this technique, we can know definitively which images' ratings have been influenced by the demographic item of choice. Subsequently, images can be evaluated and linked, on one hand, to their perceptual and semantic descriptors, and, on the other hand, to the preferences associated with viewers' demographic attributes.

Fedorovskaya, Elena A.; Lawrence, Daniel R.

2014-02-01

163

Studying Health Histories of Cancer: A New Model Connecting Cancer Incidence and Survival  

PubMed Central

The results of recent experimental and epidemiological studies provide evidence on the connection between carcinogenesis, cancer progression, and aging. Existing models, however, are traditionally focused only on one of these aspects of health deterioration. In this paper, we derive a new model of cancer, which describes the connection between the age at disease onset, the duration of disease, and life span of respective individuals. The model combines ideas used in the two hits model of carcinogenesis with those used in the Le Bras multistate model of aging with constant transition intensities. The model is used in the joint analyses of the U.S. demographic mortality data and SEER data for selected cancers. The results show that the developed approach is capable of explaining links among health history data and provides useful insights on mechanisms of cancer occurrence, disease progression, other aging-related changes, and mortality. Further developments of this model are discussed.

Yashin, Anatoli I.; Akushevich, Igor; Arbeev, Konstantin; Akushevich, Lucy; Kulminski, Alexander; Ukraintseva, Svetlana

2009-01-01

164

VA Health Care. Additional Efforts to Better Assess Joint Ventures Needed.  

National Technical Information Service (NTIS)

The Department of Veterans Affairs (VA) and the Department of Defense (DOD) have a long history of partnering to achieve more cost effective use of health care resources. Their partnerships have evolved to include joint ventures joint efforts to construct...

2008-01-01

165

Jointness: A Selected Bibliography.  

National Technical Information Service (NTIS)

JDEIS is the Joint Doctrine, Education and Training Community Electronic Information System. It encompasses a searchable Joint Doctrine Database, a Joint Education section that includes the JPME Prospective Research Topics Database, as well as award-winni...

L. Garder

2010-01-01

166

Joint Advanced Warfighting School.  

National Technical Information Service (NTIS)

When the United States employs military power, it does so as a joint force. The cornerstone for effective joint force employment remains Service competency, but truly effective Service warfighters must think, plan and fight jointly. The key to developing ...

J. M. Davis K. C. Bowen L. W. Schonenberg

2003-01-01

167

Understanding Joint Warfighting Experiments.  

National Technical Information Service (NTIS)

In October 1998 the United States Joint Forces Command (USJFCOM) established a Joint Warfighting Experimentation program to support Joint Concept Development. Experimentation is the unique scientific method for establishing whether hypothesized concepts a...

R. A. Kass

2001-01-01

168

Arthritis: Metacarpophalangeal (MP) Joint  

MedlinePLUS

... Z Hand Anatomy Find a Hand Surgeon Arthritis - MP Joint Email to a friend * required fields From * ... drift (See Figure 2). When arthritis affects the MP joints, the condition is called MP joint arthritis. ...

169

Demographic analysis from summaries of an age-structured population  

USGS Publications Warehouse

Demographic analyses of age-structured populations typically rely on life history data for individuals, or when individual animals are not identified, on information about the numbers of individuals in each age class through time. While it is usually difficult to determine the age class of a randomly encountered individual, it is often the case that the individual can be readily and reliably assigned to one of a set of age classes. For example, it is often possible to distinguish first-year from older birds. In such cases, the population age structure can be regarded as a latent variable governed by a process prior, and the data as summaries of this latent structure. In this article, we consider the problem of uncovering the latent structure and estimating process parameters from summaries of age class information. We present a demographic analysis for the critically endangered migratory population of whooping cranes (Grus americana), based only on counts of first-year birds and of older birds. We estimate age and year-specific survival rates. We address the controversial issue of whether management action on the breeding grounds has influenced recruitment, relating recruitment rates to the number of seventh-year and older birds, and examining the pattern of variation through time in this rate.

Link, W.A.; Royle, J.A.; Hatfield, J.S.

2003-01-01

170

Estimating demographic parameters using hidden process dynamic models.  

PubMed

Structured population models are widely used in plant and animal demographic studies to assess population dynamics. In matrix population models, populations are described with discrete classes of individuals (age, life history stage or size). To calibrate these models, longitudinal data are collected at the individual level to estimate demographic parameters. However, several sources of uncertainty can complicate parameter estimation, such as imperfect detection of individuals inherent to monitoring in the wild and uncertainty in assigning a state to an individual. Here, we show how recent statistical models can help overcome these issues. We focus on hidden process models that run two time series in parallel, one capturing the dynamics of the true states and the other consisting of observations arising from these underlying possibly unknown states. In a first case study, we illustrate hidden Markov models with an example of how to accommodate state uncertainty using Frequentist theory and maximum likelihood estimation. In a second case study, we illustrate state-space models with an example of how to estimate lifetime reproductive success despite imperfect detection, using a Bayesian framework and Markov Chain Monte Carlo simulation. Hidden process models are a promising tool as they allow population biologists to cope with process variation while simultaneously accounting for observation error. PMID:22373775

Gimenez, Olivier; Lebreton, Jean-Dominique; Gaillard, Jean-Michel; Choquet, Rémi; Pradel, Roger

2012-12-01

171

Prevalence, demographics and clinical characteristics of multiple sclerosis in Qatar.  

PubMed

No published epidemiologic data on multiple sclerosis (MS) in Qatar exist. Our objectives were to determine the prevalence, demographics and clinical characteristics of MS in the Middle Eastern country of Qatar. We analyzed data for Qatari MS patients fulfilling the McDonald diagnostic criteria. A total of 154 patients fulfilled the inclusion criteria. On 31 April 2010, the crude prevalence of MS in Qatar was 64.57 per 100,000 inhabitants (95% CI: 58.31-70.37). The female-to-male ratio was 1.33:1. A positive family history was found in 10.4% of included MS patients. We conclude that Qatar is now a medium-to-high risk area for MS, with some important differences in clinical characteristics as compared to other countries in the region. PMID:22968545

Deleu, Dirk; Mir, Danial; Al Tabouki, Ahmed; Mesraoua, Rim; Mesraoua, Boulenouar; Akhtar, Naveed; Al Hail, Hassan; D'souza, Atlantic; Melikyan, Gayane; Imam, Yahia Z B; Osman, Yasir; Elalamy, Osama; Sokrab, Tageldin; Kamran, Sadaat; Ruiz Miyares, Francisco; Ibrahim, Faiza

2013-05-01

172

Financial Bubbles and Business Scandals in History  

Microsoft Academic Search

This article is a survey of corporate scandals and some of the leading figures associated with them throughout the history of the joint-stock company. We find that great waves of exploration and innovation have been seen to propel speculative ventures that often prove worthless (hence the name “bubble”) and give rise to financial scandal. A look at some of history's

Kenneth R. Gray; Larry A. Frieder; George W. Clark Jr

2007-01-01

173

Validity of summing painful joint sites to assess joint-pain comorbidity in hip or knee osteoarthritis  

PubMed Central

Background Previous studies in patients with hip and knee osteoarthritis (OA) have advocated the relevance of assessing the number of painful joint sites, other than the primary affected joint, in both research and clinical practice. However, it is unclear whether joint-pain comorbidities can simply be summed up. Methods A total of 401 patients with hip or knee OA completed questionnaires on demographic variables and joint-pain comorbidities. Rasch analysis was performed to evaluate whether a sum score of joint-pain comorbidities can be calculated. Results Self-reported joint-pain comorbidities showed a good fit to the Rasch model and were not biased by gender, age, disease duration, BMI, or patient group. As a group, joint-pain comorbidities covered a reasonable range of severity levels, although the sum score had rather low reliability levels suggesting it cannot discriminate well among patients. Conclusions Joint-pain comorbidities, in other than the primary affected joints, can be summed into a joint pain comorbidity score. Nevertheless, its use is discouraged for individual decision making purposes since its lacks discriminative power in patients with minimal or extreme joint pain.

2013-01-01

174

Spacesuit mobility joints  

NASA Technical Reports Server (NTRS)

Joints for use in interconnecting adjacent segments of an hermetically sealed spacesuit which have low torques, low leakage and a high degree of reliability are described. Each of the joints is a special purpose joint characterized by substantially constant volume and low torque characteristics. Linkages which restrain the joint from longitudinal distension and a flexible, substantially impermeable diaphragm of tubular configuration spanning the distance between pivotally supported annuli are featured. The diaphragms of selected joints include rolling convolutions for balancing the joints, while various joints include wedge-shaped sections which enhance the range of motion for the joints.

Vykukal, H. C. (inventor)

1978-01-01

175

Economic - demographic models for forecasting interregional migration  

Microsoft Academic Search

A class of spatial economic - demographic forecasting models is proposed. The models combine elements of traditional Markov and economic gravity models. A base-period probability structure is modified by the changing relative distribution of economic opportunity. Estimation issues are addressed, and an empirical application to US interstate migration during the late 1970s is described. It is contended that the framework

D A Plane; P A Rogerson

1985-01-01

176

Selected Statistics: Demographic, Social, Economic, Education.  

ERIC Educational Resources Information Center

The publication, intended for persons involved in educational activities, provides selected data on demographic, social, economic, and educational characteristics of Region V, United States Department of Education. Region V comprises Illinois, Indiana, Michigan, Minnesota, Ohio, and Wisconsin. The majority of the data was drawn from the 1976…

Office of Education (DHEW), Chicago, IL. Regional Office 5.

177

A Model for External Demographic Analysis.  

ERIC Educational Resources Information Center

A data-collection model is presented for the gathering of timely information on population demographic characteristics, as well as economic, educational, environmental, and social trends. First, the paper discusses the importance of anticipating internal and external changes and establishing priorities for resource allocation in the design of a…

Hall, Barbara Ann

178

[Seasonal adjustment of monthly demographic rates].  

PubMed

The method used by the Netherlands Central Bureau of Statistics to adjust monthly demographic data to take into account seasonal variations is described. This method, the Census-X11 method, is based on moving averages techniques. (summary in ENG) PMID:12313823

De Beer, J A

1985-06-01

179

Using Demographic Studies to Project School Enrollments.  

ERIC Educational Resources Information Center

Describes how to use demographic studies to project school enrollments. Includes collecting historical enrollment data, contacting the state department of health and vital statistics, selecting an enrollment-projection method, meeting with local planning and construction department officials, determining the age of the community, and performing…

Grip, Richard S.

2002-01-01

180

Demographic and Health Survey 2000: Cambodia.  

National Technical Information Service (NTIS)

With great pleasure, we would like to introduce the first ever Cambodia Demographic and Health Survey that was conducted successfully in the year 2000. This survey is sponsored by UNFPA, UNICEF, and USAID, and technical assistance was provided by ORC Macr...

2001-01-01

181

Family Demographics, Family Functioning, and Parent Involvement.  

ERIC Educational Resources Information Center

The nation-wide study assessed the effectiveness of the various delivery systems providing early intervention services to handicapped young children. The Battelle Developmental Inventory was the primary measure of child development. A series of parent measures were used and demographic information was also collected. Data from project sites…

Lowitzer, Arthur C.

182

Asian demographic transitions: Transitions to what?  

Microsoft Academic Search

East Asia, Southeast Asia and South Asia are located along the continuum divided roughly into the mature, intermediate and earlier stages of the demographic transition, but they are moving, seemingly inexorably, towards the mature end. Even South Asia has large areas of below-replacement fertility, mostly in India, and Pakistan finally appears to be moving rapidly toward lower fertility levels. Projections

Gavin W. Jones

183

Demographic and Lifestyle Variables Associated with Obesity  

ERIC Educational Resources Information Center

Objective: Overweight and obesity rates are associated with chronic diseases and higher rates of disability and continue to rise in the United States and worldwide. The purpose of this study was to build on past research and further investigate demographic and lifestyle variables associated with increased body mass index (BMI: kg/m[squared]).…

Worthy, Sheri L.; Lokken, Kristine; Pilcher, Kenneth; Boeka, Abbe

2010-01-01

184

Arizona Indian Demographic Data: Needs and Recommendations.  

ERIC Educational Resources Information Center

Included in this report on Arizona Indian demographic data are "an evaluation of several recent studies of Indian populations" and "an extensive analysis of methods for obtaining and maintaining accurate data in the future." Recommended methods by which accurate population data for the smaller reservations should be maintained are included in the…

Taylor, Benjamin J.; Helmkamp, John

185

Demographics of Preschoolers Who Require AAC  

Microsoft Academic Search

Purpose: The purpose of the investigation was to gather demographic information pertaining to preschoolers who require augmentative and alternative communication (AAC). Method: To obtain this information, a survey was developed and then distributed to preschool speech-language pathologists (SLPs) in Pennsylvania. Results: Results indicated that approximately 12% of preschoolers receiving special education services required AAC. These children came from diverse ethnic

Cathy Binger; Janice Light

2006-01-01

186

Psychological and Demographic Correlates of Career Patterns  

ERIC Educational Resources Information Center

Recent years have witnessed a growing diversity of career patterns, resulting from the relative decline of stable employment. In the present study of 1368 employed and self-employed German adults career pattern diversity was assessed using nine pictograms. The goal was to identify psychological and demographic correlates of these patterns and to…

Reitzle, Matthias; Korner, Astrid; Vondracek, Fred W.

2009-01-01

187

Demographic Group Differences in Adolescents' Time Attitudes  

ERIC Educational Resources Information Center

In the present study, we examined demographic differences in time attitudes in a sample of 293 adolescents. Time attitudes were measured using the Adolescent Time Attitude Scale (Mello & Worrell, 2007; Worrell, Mello, & Buhl, 2011), which assesses positive and negative attitudes toward the past, the present, and the future. Generally, African…

Andretta, James R.; Worrell, Frank C.; Mello, Zena R.; Dixson, Dante D.; Baik, Sharon H.

2013-01-01

188

Population momentum for gradual demographic transitions  

Microsoft Academic Search

Population momentum is the ratio of a population's ultimate size after a demographic transition to its initial size before the transition. For an instantaneous drop to replacement fertility, Nathan Keyfitz found a simple expression M K for the momentum. However, as Keyfitz pointed out, `no one thinks that any country will drop immediately to stationary reproduction patterns'. We present results

NAN LI; SHRIPAD TULJAPURKAR

1999-01-01

189

Demographic Transition in China and its Implications  

Microsoft Academic Search

The aim of this paper is to chart the demographic transition in China, identify its proximate causes and analyze its socioeconomic implications with reference to, first, the proportion and composition of the dependent population, second, the age structure of the labor force and, third, the size and composition of households. Defined as a steady deceleration in population growth to a

Athar Hussain

2002-01-01

190

Demographic Transitions in a Sicilian Rural Town  

Microsoft Academic Search

Combining archival, ethnographic, vital, and oral historical data, this paper compares the experiences of population growth and demographic transi tion among different social classes of a Sicilian rural town from 1850 to the pres ent. Four locally named groups have dominated this town's social life during most of the period in question—gentry, artisans, landed, and landless peasants. Of particular concern

Jane Schneider; Peter Schneider

1984-01-01

191

Population concentration, urbanization, and demographic transition  

Microsoft Academic Search

This paper investigates how urbanization and demographic transition interrelate with each other via merits (agglomeration economies) and demerits (congestion diseconomies) of population concentration. It reveals the mechanism by which agglomeration economies and congestion diseconomies affect the fertility rate. Furthermore, analysis also shows that by assuming declines in infant and child mortality rate, the model developed in this paper can replicate

Yasuhiro Sato; Kazuhiro Yamamoto

2005-01-01

192

Demographic Transition, Income Distribution, and Economic Growth  

Microsoft Academic Search

This article investigates the dynamic interactions among demographic transition, income distribution, and economic growth. Consistent with empirical evidence we show that fertility and income distribution follow an inverted U-shaped dynamics in the process of economic development. In the first stage fertility increases and income inequality widens, whereas in the second stage fertility declines, income becomes more equally distributed, human capital

Momi Dahan; Daniel Tsiddon

1998-01-01

193

Economic and Demographic Predictors of Inclusive Education  

ERIC Educational Resources Information Center

This study investigated economic and demographic predictors of levels of inclusion of students with disabilities in 129 school districts. Multiple regression analysis was utilized to address the following research questions: (a) Is there a relationship between economic factors and percentage of highly included students with disabilities in general…

Cosier, Meghan E.; Causton-Theoharis, Julie

2011-01-01

194

Understanding China's Demographic Dividends and Labor Issue  

ERIC Educational Resources Information Center

One of the major concerns about the one-child policy is its negative impact on the current and future labor force in China. People have talked about the Lewis Turning Point and the end of demographic dividends. Some of these arguments, however, can be misleading. The working-age population (ages 15 to 59) can be treated as the potential labor…

Peng, Xizhe

2013-01-01

195

Demographic and Health Survey 2001: Nepal.  

National Technical Information Service (NTIS)

The 2001 Nepal Demographic and Health Survey (NDHS) is a nationally representative survey of 8,726 women age 15-49 and 2,261 men age 15-59. This survey is the sixth in a series of national-level population and health surveys and the second comprehensive s...

2002-01-01

196

Science history  

Microsoft Academic Search

A science history content in a science course is a humanizing element which makes the science appeal more strongly to imaginative and creative minds. It also provides perspective and prepares the pupil for the ever-changing character of modern science. Examples are given of charts which can key science history to its social and political background and which illustrate the interdependence

A J Woodall

1967-01-01

197

Lunar History.  

National Technical Information Service (NTIS)

This section of the workshop describes the history of the moon, and offers explanations for the importance of understanding lunar history for engineers and users of lunar simulants. Included are summaries of the initial impact that is currently in favor a...

J. E. Edmunson

2009-01-01

198

Canadian History.  

ERIC Educational Resources Information Center

Includes 22 articles that address Canadian history and the importance of having students honor Canada's past by providing articles relating to the areas of History and Social Studies covering: historical fiction as instructional material; Canadian scientists; agricultural fairs; the Historical Foundation; social science books on Canada; student…

School Libraries in Canada, 2003

2003-01-01

199

Digital History  

NSDL National Science Digital Library

Utilizing digital and online technologies to teach different disciplines continues to be quite popular, and the Digital History website will be a most welcome find for teachers (and students) of American history. Developed in collaboration with the University of Houston, the Chicago Historical Society, the Museum of Fine Arts in Houston and several other entities the site includes an online American history textbook, an interactive timeline, a multimedia section, and a very rich selection of primary source materials. The multimedia section is a real find, as it contains several well-thought out lectures with titles like "The History of Domestic Violence", "The Cultural Civil War of the 1960s", and "America Today and America Past". Students will also appreciate the writing guide area, as it contains several short essays on how to write in a history class and how to compose a critical book review.

200

[Vascularized joint transfer for finger joint reconstruction].  

PubMed

In a retrospective clinical study 16 vascularized joint transfers to the hand with an average follow-up of 8.2 (3 - 15) years were evaluated. The finger joint defect was caused by trauma in 12 patients, tumour in 2 patients and infection and congenital deformity in 1 patient each. There were 14 men and 2 women. The mean age range was 26 (2 - 42) years. In 6 cases a partial vascularized joint transfer was carried out, with the transplant being harvested in two cases from non-replantable finger according to the "tissue bank concept" according to Chase and in the other two cases from the PIP-joint of the second toe. In 10 patients a complete vascularized joint transfer was carried out, with the joint being harvested from the hand in 6 cases and from the 2nd toe in 4 cases. The following criteria were evaluated: active range of motion (neutral-0-method), postoperative arthritis, growth and complications. Active range of motion of the transplanted joint was for partial PIP-joint transfer Ex/Flex 0/20/65 degrees und for partial MP-joint transfer 0/20/30 degrees . After DIP-to-PIP-joint transposition active range of motion was measured Ex/Flex 0/20/60 degrees , after PIP-to-PIP transposition 0/30/60 degrees , PIP-to-MP-transposition 0/20/80 degrees and after MP-to-MP-transposition 0/20/57 degrees . The results after microvascular PIP-joint transfer from the 2nd toe for PIP-joint reconstruction were 0/25/58 degrees for PIP-joint reconstruction and 0/15/70 degrees for MP-joint reconstruction. Arthritic changes could be seen in 3 out of 4 patients with partial vascularized joint transfer. In all complete joint transfers there was no clinical and radiological evidence of arthritis even after 15 years. In the two skeletal immature patients at the time of transfer, normal growth compared to the contralateral donor site could be seen. In 8 out of 14 patients complications occurred. In 4 cases tendolysis of the extensor tendon was necessary. In 4 patients skeletal malalignment (3 x sagittal plane, 1 x rotation) was diagnosed. In one patient flexor pulley reconstruction was necessary in order to correct a bowstring deformity. Indications for vascularized joint transfer at the finger in children is set because of lack of therapy option offering normal growth potential. In adults vascularized joint transfer is indicated in case of contraindication for prosthetic joint replacement or arthrodesis. PMID:17724645

Hierner, R; Berger, A K; Shen, Z-L

2007-08-01

201

Proprioception and joint stability  

Microsoft Academic Search

In the present paper the current clinical knowledge about proprioception is given for the shoulder, knee, ankle, elbow and the radiocarpal joint. Proprioceptive capabilities are decreased after joint injuries such as ACL or meniscus tears, shoulder dislocation, ankle sprain and in joints with degenerative joint disease. Some surgical procedures seem to restore the proprioceptive abilities; others do not. Elastic knee

J. Jerosch; M. Prymka

1996-01-01

202

History of the Space Radiation Effects (SPACERAD) Program for the joint USAF/NASA CRRES mission. Part 1. From the origins through the launch, 1981-1990. Interim report  

SciTech Connect

The history narrates the Space Radiation Effects (SPACERAD) Program from its origins in 1981 through the launch of the SPACERAD experiments on the USAF/NASA Combined Release/Radiation Effects Satellite (CRRES) on July 25, 1990 and the initial data results in October 1990. The SPACERAD Program comprised a coordinated schedule of space-and-ground testing of state-of-the-art microelectronics, together with new satellite measurements of the Earth's radiation belts. The goals for the program were to produce improved standards and procedures for ground-testing future space microelectronics and new dynamic models of the radiation belts. The history discusses programmatic, management and funding issues that arose in the course of its realization.

Liebowitz, R.P.

1992-03-16

203

[Total joint arthroplasty].  

PubMed

Control of the disease activity is enabled due to the progress of drug therapy for rheumatoid arthritis. However, surgical treatments are necessary for unresponsive cases to the drug or for achieving higher QOL, and we can attain more tight control or cure by combination of drug therapy and surgical treatments. Total joint arthroplasty provides indolence, mobility, stability and is an useful joint reconstruction method. Shoulder and elbow joint work as a reach function together, and total joint arthroplasty become adaptation when extensive joint destruction or severe pain occurrs. With the usage of biologic agents joint repair is possible in small joints, but if the joint destruction progress in weight-bearing joints, repair is impossible and total joint arthroplasty can be required. PMID:23961679

Mibe, Junya; Yamamoto, Kengo

2013-07-01

204

Permanent anterior dislocation of the proximal tibiofibular joint.  

PubMed

We report two patients with permanent dislocation of the proximal tibiofibular joint and no history of trauma. Both needed operation, one for persistent pain and the other for common peroneal nerve involvement, and both had a good result. PMID:2925742

Molitor, P J; Dandy, D J

1989-03-01

205

Demographic Shifts in the Czech Republic after 1989: A Second Demographic Transition View  

Microsoft Academic Search

A dramatic change in fertility,family formation and living arrangements tookplace in the Czech Republic over the 1990s. Theestablishment of democracy, profound socialtransformation and transition to the marketeconomy affected the values and demographicbehaviour of the young Czech generation. Thispaper examines whether these demographic shiftscan be interpreted within the framework of thesecond demographic transition. The theoreticalpart discusses the idea of the transition,outlining

Tomáš Sobotka; Kryštof Zeman; Vladimíra Kantorová

2003-01-01

206

History & Policy  

NSDL National Science Digital Library

Some might wonder about the connection between history and contemporary policymaking. Well, the passionate and dedicated individuals at the History & Policy organization are committed to looking at the intersection of these two areas of inquiry and research. History & Policy is a collaboration between the University of Cambridge, The Institute of Historical Research, and The London School of Hygiene and Tropical Medicine. It is managed by its four founding historians, and visitors to the site can browse their papers by theme, author, or keyword. The papers offer a wide range of perspectives on history and policy-related matters, and recent works have included papers on social housing and tenant participation, genocide in the twentieth century, and "The Prime Minister as World Statesman". Practicing historians can also sign up to join their network, and anyone is welcome browse through their events calendar and register for email updates.

2008-01-01

207

Family History  

MedlinePLUS

... Aneurysm Complications Post Treatment and Outcome GTranslate Understanding : Family History Familial intracranial aneurysms are generally defined as the presence of two or more family members among first- and second-degree relatives with ...

208

New Approaches to Demographic Data Collection  

PubMed Central

As population scientists have expanded the range of topics they study, increasingly considering the interrelationship between population phenomena and social, economic, and health conditions, they have expanded the kinds of data collected and have brought to bear new data collection techniques and procedures, often borrowed from other fields. These new approaches to demographic data collection are the concern of this essay. We consider three main topics: new developments in sampling procedures; new developments in fieldwork procedures; and new developments in the kind of information collected in demographic and social surveys. We conclude with some comments on data sharing in the social research community and a list of major Chinese surveys publicly available to researchers. Where possible we illustrate our points with Chinese examples.

Treiman, Donald J.; Lu, Yao; Qi, Yaqiang

2013-01-01

209

Demographic perspectives on Saudi Arabia's development.  

PubMed

Demographic movements likely to be taking place in Saudi Arabia were hypothesized on the basis of general knowledge. The discussion reports on population size, general Arab demographic patterns, general determinants of fertility, Arab fertility patterns, Saudi fertility patterns, mortality in general, mortality in the Middle East, mortality in Saudi Arabia, Saudi Arabian population growth, immigration, the changing composition of the work force, and third plan targets. Some doubt exists as to the size of Saudi Arabia's population, but there is little question that the total is growing rapidly. This expansion is taking place through stepped up immigration and a relatively high natural growth of indigenous Saudis, but statistics on population size, structure, and on the number of births and deaths leaves the magnitude of a number of important demographic trends in doubt. Yet, considerable evidence exists that several of the Arab countries in the region with fairly good demographic data are likely to have similar demographic patterns. In depth analysis of the demographic dynamics of these countries, particularly Jordan and Kuwait, identified several common elements bearing on several key parameters. Using what Saudi data is available and making comparisons with these neighboring countries, one can, based on expected levels of birth and death rates, indirectly infer the natural growth of Saudi Arabia's population. With several notable exceptions, Saudi Arabia's demographic patterns show a marked similarity to those experienced in the region as a whole. The average rate of population growth in both Saudi Arabia and the Arab region is about 3% a year and in both instances fertility rates are high. The demographic structure of these countries is characterized by the youthfulness of the population. In most of the Arab countries, the population aged 15 years or under accounts for over 48% of the population. The rate of the economically active population is low, ranging from 22% to 32% of the total population, with the female participation rate varying from 3.5% to 18.5%. In the nonagricultural sector, the average activity rate of women over the age of 15 usually does not exceed 6%. Arab countries are also characterized by their high infant mortality rates. In 1975 these rates ranged from 60 to 200/1000. Illiteracy rates for the group, as a whole, are also high, and they are significantly higher among women than among men. A multipurpose survey conducted in Saudi Arabia during 1976 and 1977 reported a live birthrate of 54.2/1000. This is somewhat above the UN figure of 49.5 for the country and over the average for Arab countries of 46.6 for 1975. The mortality rate for the Saudi population is 14.1/1000. If one accepts the birth and death rates indicated by the multipurpose survey, the population is growing at a national rate of 3% or more per year. PMID:12340437

Looney, R E

1985-06-01

210

Global demographic trends and future carbon emissions  

PubMed Central

Substantial changes in population size, age structure, and urbanization are expected in many parts of the world this century. Although such changes can affect energy use and greenhouse gas emissions, emissions scenario analyses have either left them out or treated them in a fragmentary or overly simplified manner. We carry out a comprehensive assessment of the implications of demographic change for global emissions of carbon dioxide. Using an energy–economic growth model that accounts for a range of demographic dynamics, we show that slowing population growth could provide 16–29% of the emissions reductions suggested to be necessary by 2050 to avoid dangerous climate change. We also find that aging and urbanization can substantially influence emissions in particular world regions.

O'Neill, Brian C.; Dalton, Michael; Fuchs, Regina; Jiang, Leiwen; Pachauri, Shonali; Zigova, Katarina

2010-01-01

211

Simulation of Demographic Change in Palestinian Territories  

NASA Astrophysics Data System (ADS)

Mortality, birth rates and retirement play a major role in demographic changes. In most cases, mortality rates decreased in the past century without noticeable decrease in fertility rates, leading to a significant increase in population growth. In many poor countries like Palestinian Territories the number of births has fallen and the life expectancy increased. In this paper we concentrate on measuring, analyzing and extrapolating the age structure in Palestine a few decades ago into the future. A Fortran program has been designed and used for the simulation and analysis of our statistical data. This study of demographic change in Palestine has shown that Palestinians will have in future problems as the strongest age cohorts are the above-60-year olds. We therefore recommend the increase of both the retirement age and female employment.

Sumour, M. A.; El-Astal, A. H.; Shabat, M. M.; Radwan, M. A.

212

Exoplanet Demographics with WFIRST-AFTA  

NASA Astrophysics Data System (ADS)

Measurements of the demographics of exoplanets over a broad range of planet and host-star properties provide fundamental empirical constraints on theories of planet formation and evolution. Because of its unique sensitivity to low-mass, long-period, and free-floating planets, microlensing is an essential complement to our arsenal of planet detection methods. I outline the expected returns of a microlensing survey with WFIRST-AFTA. When combined with the results from complementary surveys such as Kepler, WFIRST-AFTA will yield a nearly complete picture of the demographics of planetary systems throughout the Galaxy, providing fundamental tests of planet formation theories, and informing our understanding of the frequency and potential habitability of low mass planets located in the habitable zones of their host stars.

Gaudi, B. S.; WFIRST-AFTA Science Definition Team

2014-01-01

213

Complexity and Demographic Explanations of Cumulative Culture  

PubMed Central

Formal models have linked prehistoric and historical instances of technological change (e.g., the Upper Paleolithic transition, cultural loss in Holocene Tasmania, scientific progress since the late nineteenth century) to demographic change. According to these models, cumulation of technological complexity is inhibited by decreasing— while favoured by increasing—population levels. Here we show that these findings are contingent on how complexity is defined: demography plays a much more limited role in sustaining cumulative culture in case formal models deploy Herbert Simon's definition of complexity rather than the particular definitions of complexity hitherto assumed. Given that currently available empirical evidence doesn't afford discriminating proper from improper definitions of complexity, our robustness analyses put into question the force of recent demographic explanations of particular episodes of cultural change.

Querbes, Adrien; Vaesen, Krist; Houkes, Wybo

2014-01-01

214

Is the demographic dividend an education dividend?  

PubMed

The effect of changes in age structure on economic growth has been widely studied in the demography and population economics literature. The beneficial effect of changes in age structure after a decrease in fertility has become known as the "demographic dividend." In this article, we reassess the empirical evidence on the associations among economic growth, changes in age structure, labor force participation, and educational attainment. Using a global panel of countries, we find that after the effect of human capital dynamics is controlled for, no evidence exists that changes in age structure affect labor productivity. Our results imply that improvements in educational attainment are the key to explaining productivity and income growth and that a substantial portion of the demographic dividend is an education dividend. PMID:24302530

Crespo Cuaresma, Jesús; Lutz, Wolfgang; Sanderson, Warren

2014-02-01

215

Glomus tumor of the lateral aspect of the knee joint  

Microsoft Academic Search

Background We report a rare case of glomus tumor that occurred in the lateral joint of the knee. A 54?year?old man was referred to us with a 3?year history of lateral pain in the left knee and the diagnosis of lateral meniscus injury. Physical examination revealed a small trigger point localized just on the lateral joint space. Magnetic resonance imaging

Kohjirou Okahashi; Kazuya Sugimoto; Makoto Iwai; Kouji Kaneko; Masayuki Samma; Yoshiyuki Fujisawa; Yoshinori Takakura

2004-01-01

216

Chemical kinetic model of interfacial degradation of adhesive joints  

Microsoft Academic Search

Mechanical properties of adhesive joints are degraded in the presence of water. The progressive decrease in strength has been attributed to propagation of interfacial crack. Water diffusion and stress distribution within the adhesive joint as a function of time has been modeled using finite elements in this study. The stress history at the interface displayed spatially invariant characteristics similar to

David C. C. Lam; Fan Yang; Pin Tong

1999-01-01

217

The Demographic Transition: Causes and Consequences  

PubMed Central

This paper develops the theoretical foundations and the testable implications of the various mechanisms that have been proposed as possible triggers for the demographic transition. Moreover, it examines the empirical validity of each of the theories and their significance for the understanding of the transition from stagnation to growth. The analysis suggests that the rise in the demand for human capital in the process of development was the main trigger for the decline in fertility and the transition to modern growth

Galor, Oded

2013-01-01

218

Global demographic trends and social security reform  

Microsoft Academic Search

How sustainable are the current social security systems in the developed economies, given the projected demographic trends? The most recent literature has answered this question through dynamic general-equilibrium models in a closed-economy framework. This paper provides a new quantitative benchmark of analysis for this question represented by a two-region model (South and North) of the world economy where capital flows

Orazio Attanasio; Sagiri Kitao; Giovanni L. Violante

2007-01-01

219

Intelligent system to study demographic evolution  

NASA Astrophysics Data System (ADS)

With three centuries of existence, the study of population's behavior implies the manipulation of large amounts of incomplete and imprecise data with high dimensionality. By virtue of its multidisciplinary character, the work in demography involves at least historicists, statisticians and computer scientists/programmers. Moreover, successful demographic analysis requires qualified experts, who have succeeded in analysing data through many views and relate different sources of information, including their personal knowledge of the epoch or regions under study. In this paper, we present an intelligent system to study demographic evolution (ISSDE). This system has a module based on on-line analytical processing (OLAP), which permits conducting multiple analysis, combining many data dimensions. It has a deductive database system, which allows the execution of elaborated queries through the database. It has another module for date treatment (generalization and/or reduction); and, at last, a data mining module to discover nontrivial relations hidden within data. We discover the data treatment procedure with two phases: data generalization and data reduction. In data generalization, utilizing knowledge about concept hierarchies and relevance of data, aggregation of attribute values is performed. In the data reduction phase, rough set theory is applied to compute the minimal attribute set. We highlight the advantages of combining attribute value generalization with rough set theory, to find a subset of attributes that lets the mining process discover more useful patterns, by providing results from the application of the C5.0 algorithm in a demographic relational database.

Rodrigues, M. De Fatima; Ramos, Carlos; Henriques, Pedro R.

1999-02-01

220

Rural Household Demographics, Livelihoods and the Environment  

PubMed Central

This paper reviews and synthesizes findings from scholarly work on linkages among rural household demographics, livelihoods and the environment. Using the livelihood approach as an organizing framework, we examine evidence on the multiple pathways linking environmental variables and the following demographic variables: fertility, migration, morbidity and mortality, and lifecycles. Although the review draws on studies from the entire developing world, we find the majority of micro-level studies have been conducted in either marginal (mountainous or arid) or frontier environments, especially Amazonia. Though the linkages are mediated by many complex and often context-specific factors, there is strong evidence that dependence on natural resources intensifies when households lose human and social capital through adult morbidity and mortality, and qualified evidence for the influence of environmental factors on household decision-making regarding fertility and migration. Two decades of research on lifecycles and land-cover change at the farm level have yielded a number of insights about how households make use of different land-use and natural resource management strategies at different stages. A thread running throughout the review is the importance of managing risk through livelihood diversification, ensuring future income security, and culture-specific norms regarding appropriate and desirable activities and demographic responses. Recommendations for future research are provided.

de Sherbinin, Alex; VanWey, Leah; McSweeney, Kendra; Aggarwal, Rimjhim; Barbieri, Alisson; Henry, Sabina; Hunter, Lori M.; Twine, Wayne

2008-01-01

221

Rural Household Demographics, Livelihoods and the Environment.  

PubMed

This paper reviews and synthesizes findings from scholarly work on linkages among rural household demographics, livelihoods and the environment. Using the livelihood approach as an organizing framework, we examine evidence on the multiple pathways linking environmental variables and the following demographic variables: fertility, migration, morbidity and mortality, and lifecycles. Although the review draws on studies from the entire developing world, we find the majority of micro-level studies have been conducted in either marginal (mountainous or arid) or frontier environments, especially Amazonia. Though the linkages are mediated by many complex and often context-specific factors, there is strong evidence that dependence on natural resources intensifies when households lose human and social capital through adult morbidity and mortality, and qualified evidence for the influence of environmental factors on household decision-making regarding fertility and migration. Two decades of research on lifecycles and land-cover change at the farm level have yielded a number of insights about how households make use of different land-use and natural resource management strategies at different stages. A thread running throughout the review is the importance of managing risk through livelihood diversification, ensuring future income security, and culture-specific norms regarding appropriate and desirable activities and demographic responses. Recommendations for future research are provided. PMID:19190718

de Sherbinin, Alex; Vanwey, Leah; McSweeney, Kendra; Aggarwal, Rimjhim; Barbieri, Alisson; Henry, Sabina; Hunter, Lori M; Twine, Wayne

2008-02-01

222

Butt Joint Tool Commissioning  

SciTech Connect

ITER Central Solenoid uses butt joints for connecting the pancakes in the CS module. The principles of the butt joining of the CICC were developed by the JAPT during CSMC project. The difference between the CSMC butt joint and the CS butt joint is that the CS butt joint is an in-line joint, while the CSMC is a double joint through a hairpin jumper. The CS butt joint has to carry the hoop load. The straight length of the joint is only 320 mm, and the vacuum chamber around the joint has to have a split in the clamp shell. These requirements are challenging. Fig.1 presents a CSMC joint, and Fig.2 shows a CS butt joint. The butt joint procedure was verified and demonstrated. The tool is capable of achieving all specified parameters. The vacuum in the end was a little higher than the target, which is not critical and readily correctable. We consider, tentatively that the procedure is established. Unexpectedly, we discover significant temperature nonuniformity in the joint cross section, which is not formally a violation of the specs, but is a point of concern. All testing parameters are recorded for QA purposes. We plan to modify the butt joining tool to improve its convenience of operation and provide all features necessary for production of butt joints by qualified personnel.

Martovetsky, N N

2007-12-06

223

Historical sampling reveals dramatic demographic changes in western gorilla populations  

PubMed Central

Background Today many large mammals live in small, fragmented populations, but it is often unclear whether this subdivision is the result of long-term or recent events. Demographic modeling using genetic data can estimate changes in long-term population sizes while temporal sampling provides a way to compare genetic variation present today with that sampled in the past. In order to better understand the dynamics associated with the divergences of great ape populations, these analytical approaches were applied to western gorillas (Gorilla gorilla) and in particular to the isolated and Critically Endangered Cross River gorilla subspecies (G. g. diehli). Results We used microsatellite genotypes from museum specimens and contemporary samples of Cross River gorillas to infer both the long-term and recent population history. We find that Cross River gorillas diverged from the ancestral western gorilla population ~17,800 years ago (95% HDI: 760, 63,245 years). However, gene flow ceased only ~420 years ago (95% HDI: 200, 16,256 years), followed by a bottleneck beginning ~320 years ago (95% HDI: 200, 2,825 years) that caused a 60-fold decrease in the effective population size of Cross River gorillas. Direct comparison of heterozygosity estimates from museum and contemporary samples suggests a loss of genetic variation over the last 100 years. Conclusions The composite history of western gorillas could plausibly be explained by climatic oscillations inducing environmental changes in western equatorial Africa that would have allowed gorilla populations to expand over time but ultimately isolate the Cross River gorillas, which thereafter exhibited a dramatic population size reduction. The recent decrease in the Cross River population is accordingly most likely attributable to increasing anthropogenic pressure over the last several hundred years. Isolation of diverging populations with prolonged concomitant gene flow, but not secondary admixture, appears to be a typical characteristic of the population histories of African great apes, including gorillas, chimpanzees and bonobos.

2011-01-01

224

DEMOGRAPHIC UNCERTAINTY IN ECOLOGICAL RISK ASSESSMENTS. (R825347)  

EPA Science Inventory

We built a Ricker's model incorporating demographic stochasticity to simulate the effects of demographic uncertainty on responses of gray-tailed vole (Microtus canicaudus) populations to pesticide applications. We constructed models with mark-recapture data collected from populat...

225

The influence of demographic stochasticity on evolutionary dynamics and stability.  

PubMed

We derive the frequency-dependent selection coefficient caused by "demographic" stochasticity resulting from the random sampling of opponents an individual faces during behavioral "contests" with other individuals. The mean, variance, and higher moments of fitness all influence the direction and strength of selection. A frequency-dependent trait can be stable when an individual's fitness depends upon an infinite number of contests with other individuals and unstable when it depends upon a finite number of contests. Conversely, unstable equilibria for an infinite number of contests can be stable when there is a finite number of contests. At stable equilibria for a finite number of contests, higher moments of fitness can outweigh the joint influence of the first two moments so that natural selection favors "within-generation" or developmental-trait variation (also known as phenotypic plasticity) contrary to the claim that natural selection always acts against such variation. We use second-moment estimates of the fitness functions in a diffusion approximation to compute fixation probabilities of competing strategies. These estimates are shown to be qualitatively consistent with those derived from simulations when population sizes are sufficiently large to ignore the contribution of higher-moment terms. We also show that explicit solutions to the diffusion approximation only exist for pair-wise interactions that lead to positive frequency-dependent selection. PMID:23810907

Shpak, Max; Orzack, Steven Hecht; Barany, Ernest

2013-09-01

226

Semiconstrained Distal Radioulnar Joint Prosthesis  

PubMed Central

Distal radioulnar joint (DRUJ) problems can occur as a result of joint instability, abutment, or incongruity. The DRUJ is a weight-bearing joint; the ulnar head is frequently excised either totally or partially, and in some cases it is fused, because of degenerative, rheumatoid, or posttraumatic arthritis. Articles about these procedures report the ability to pronate and supinate, but they rarely discuss grip strength, and even less do they address lifting capacity. We report the long term results of the first 35 patients who underwent total DRUJ arthroplasty with the Aptis DRUJ prosthesis after 5 years follow-up. Surgical indications were all causes of dysfunctional DRUJ (degenerative, posttraumatic, autoimmune, congenital). We recorded data for patient demographics, range of motion (ROM), strength, and lifting capacity of the operated and of the nonoperated extremity. Pain and functional assessments were also recorded. The Aptis DRUJ prosthesis, a bipolar self-stabilizing DRUJ endoprosthesis that restores forearm function, consists of a semiconstained and modular implant designed to replace the function of the ulnar head, the sigmoid notch of the radius, and the triangular fibrocartilage ligaments. The surgical technique is presented in detail. The majority of the patients regained adequate ROM and improved their strength and lifting capacity to the operated side. Pain and activities of daily living were improved. Twelve patients experienced complications, most commonly being extensor carpi ulnaris (ECU) tendinitis, ectopic bone formation, bone resorption with stem loosening, low-grade infection, and need for ball replacement. The Aptis total DRUJ replacement prosthesis is an alternative to salvage procedures that enables a full range of motion as well as the ability to grip and lift weights encountered in daily living activities.

Savvidou, Christiana; Murphy, Erin; Mailhot, Emilie; Jacob, Shushan; Scheker, Luis R.

2013-01-01

227

Pressure suit joint analyzer  

NASA Technical Reports Server (NTRS)

A measurement system for simultaneously measuring torque and angular flexure in a pressure suit joint is described. One end of a joint under test is held rigid. A torque transducer is pivotably supported on the other movable end of a joint. A potentiometer is attached to the transducer by an arm. The wiper shaft of the potentiometer is gripped by a reference arm that rotates the wiper shaft the same angle as the flexure of joint. A signal is generated by the potentiometer which is representative of the joint flexure. A compensation circuit converts the output of the transducer to a signal representative of joint torque.

Vykukal, H. C.; Webbon, B. W. (inventors)

1982-01-01

228

Map History: History of Cartography  

NSDL National Science Digital Library

Compiled by Tony Campbell, Map Librarian at the British Library, this site is a gateway to the History of Cartography. Users will find information on a variety of map-related resources, including conferences, fellowships, current research guides, journals, lecture series, map collections, and map interest societies. Additional features include a list of related links and a brief introduction to MapHist, the Cartographic history discussion list.

1996-01-01

229

EASE History  

NSDL National Science Digital Library

The educational environment of the web continues to be transformed by compelling and exciting projects, and EASE History is one fine example of such an endeavor. Started by a team of scholars and researchers at Michigan State University, the EASE History website is an open learning environment that "supports flexibly adaptive thinking, the learning of difficult material, and open-mindedness. The site's primary focus is on assisting people to learn about various aspects of United States history through the creative use of video clips and photographs. To accomplish this, the site uses the prism of US presidential campaign ads and other related historical events. Users may want to start by taking in the "Tour" section of the site, which provides a brief overview of how the site's materials will be best utilized. Overall, this site provides a rich and interactive learning environment that may serve as the template for other such efforts.

230

History Net  

NSDL National Science Digital Library

The Weider History Group publishes a wide range of military history magazines, including "America's Civil War" and "Civil War Times". They've also been generous enough to create this website, which offers a wide range of articles from their different publications. First-time visitors to the homepage may want to start out by taking a shot at the "Daily Quiz", which offers up a range of questions on everything from steamship battles to military operations in the South Pacific. Next, visitors may wish to click on over to the "Features" area, which includes articles culled from the magazines on Marine POWs, the Battle of New Orleans, as well as noted gunfighter Ben Thompson and his brother Billy. Moving on, visitors can also take part in the online forums where they can ask questions about battle tactics, the history of ground warfare, and the USS Ironsides.

231

Lunar History  

NASA Technical Reports Server (NTRS)

This section of the workshop describes the history of the moon, and offers explanations for the importance of understanding lunar history for engineers and users of lunar simulants. Included are summaries of the initial impact that is currently in favor as explaining the moon's formation, the crust generation, the creation of craters by impactors, the era of the lunar cataclysm, which some believe effected the evolution of life on earth, the nature of lunar impacts, crater morphology, which includes pictures of lunar craters that show the different types of craters, more recent events include effect of micrometeorites, solar wind, radiation and generation of agglutinates. Also included is a glossary of terms.

Edmunson, Jennifer E.

2009-01-01

232

Jointness A Selected Bibliography.  

National Technical Information Service (NTIS)

To assist researchers in a better understanding of how the United States armed services work together, the U.S. Army War College Library presents Jointness: A Selected Bibliography. A revised and updated version of our earlier bibliographies on jointness,...

2000-01-01

233

Large displacement spherical joint  

DOEpatents

A new class of spherical joints has a very large accessible full cone angle, a property which is beneficial for a wide range of applications. Despite the large cone angles, these joints move freely without singularities.

Bieg, Lothar F. (Albuquerque, NM); Benavides, Gilbert L. (Albuquerque, NM)

2002-01-01

234

Joints and Movements.  

National Technical Information Service (NTIS)

The report contains an explanation of anatomical concepts of joints and movements necessary in biomedical and physical therapy education. Upon completion of pamphlet, reader will be able to: (1) identify movements at any joint in the human body, (2) diffe...

P. Jacoby-Lockhart H. B. Slotnick

1979-01-01

235

Environment, migration and the European demographic deficit  

NASA Astrophysics Data System (ADS)

Many countries in the more developed world, and some in the less developed, are facing new economic and social pressures associated with the ageing of their populations. Europe, in particular, is forecast to have a demographic deficit, which may be alleviated by in-migration to the region. However, several commentators have proposed that Europe will not be able to successfully compete with other regions, in particular Asia, in the coming years for the skills it will require. This letter explores these themes, arguing that climate change will increase the attractiveness of Europe as a destination of economic choice for future skilled workers, to the detriment of more environmentally challenged regions.

Harper, Sarah

2012-03-01

236

[The demographic situation in Romania. Where to?].  

PubMed

This is the text of an interview with Vasile Ghetau on the demographic situation of Romania at the end of the Ceausescu era. Dr. Ghetau points out the high levels of infant mortality, declines in life expectancy for both sexes, and continued low levels of fertility despite vigorous pronatalist measures such as the banning of induced abortion. He suggests that these negative trends are directly linked to the fact that the regime's population policy violated individual human rights; the deteriorating economic condition of the country; and shortages of many essentials, including food, heat, medicines, and health services generally. PMID:12343118

Boja, I

1990-01-01

237

The Evolution of Transfers and Life Histories  

PubMed Central

Much of life history theory analyzes life histories of independent, isolated individuals, who grow, forage, reproduce, and die. However, in many species social interactions such as food sharing are a key part of the life history strategy, altering the energetic budget constraint. Transfers and sharing raise reproductive success and also alter the fitness impact of other aspects of the life history. We discuss a variety of traits and behaviors for which transfers are important, synthesizing results from a number of earlier papers. Topics include the U-shaped mortality curve, post reproductive survival, causes of early life mortality decline, why intergenerational transfers evolve and co-evolve with longevity, time preference, sexual dimorphism and sexual differences in transfers, menopause, demographic advantages of social sharing, and consequences of social sharing for life history evolution.

Cyrus, C. Y.

2012-01-01

238

Minting History.  

ERIC Educational Resources Information Center

Presents a project where fourth-grade students depicted images on coins to reflect important conflicts in Canadian history, such as September 11, 2001. Explains how to create the coins in detail. States that the students each wrote a "proclamation" that described their time period depicted on the coins. (CMK)

Kohl, Gary

2003-01-01

239

Making History  

ERIC Educational Resources Information Center

Jennifer Dorman was in a fix. Teaching ninth-grade US history at Holicong Middle School in Doylestown, Pennsylvania, Dorman wanted to tap into her students' interest in creating "something of value not just for their teachers, but something they could share with other students and people." But that required something a conventional paper-based…

Shein, Esther

2008-01-01

240

History & Policy  

NSDL National Science Digital Library

It's an old saw that those who forget the past are doomed to repeat it, but the History & Policy group takes this maxim very seriously. The group represents a collaboration between the University of Cambridge, The Institute of Historical Research, and The London School of Hygiene and Tropical Medicine. The purpose of the group is to "demonstrate the relevance of history to contemporary policymaking" and to increase the influence of historical research over current policy. Currently, their core output happens to be their papers, which are available from their homepage. Visitors can click on the "H&P papers" area to read through the latest papers, and they can also browse around via subject heading. Some of the recent titles include "North Korea and the nuclear threat", "Why history matters-and why medieval history also matters", and "China, globalization and the west: A British debate, 1890-1914". Additionally, visitors can sign up to join their email list and learn more about their network of historians.

241

History of \\  

Microsoft Academic Search

Church's thesis claims that any "reasonablecomputer" may be simulated by a Turing machine.The "strong" thesis says that the simulation may beperformed with only polynomial slowdown. This documentis both a history of "Church's thesis" -- and particularlyof the notion that it is a statement about physics-- and an opinionated philosophical statement.Keywords --- Church's thesis, rigorous physics, polynomial time,effective continuous mathematics, computable

Warren D. Smith

242

Joint Chiefs of Staff and the Prelude to the War in Vietnam, 1954- 1959.  

National Technical Information Service (NTIS)

The Historical Division, Joint Chiefs of Staff, the predecessor of the present Joint History Office, produced the manuscript 'The Joint Chiefs of Staff and the War in Vietnam, 1954-1959,' in 1972 as a Top Secret document. Based largely upon then classifie...

D. A. Armstrong G. A. Cosmas J. Shulimson W. J. Webb

2007-01-01

243

Temporomandibular joint dislocation: experiences from Zaria, Nigeria  

PubMed Central

Objectives Dislocation of the temporomandibular joint may occur for various reasons. Although different invasive methods have been advocated for its treatment, this study highlights the value of non-invasive treatment options even in chronic cases in a resource-poor environment. Materials and Methods A seven-year retrospective analysis of all patients managed for temporomandibular joint dislocation in our department was undertaken. Patient demographics, risk factors associated with temporomandibular joint dislocation and treatment modalities were retrieved from patient records. Results In all, 26 patients were managed over a seven-year period. Males accounted for 62% of the patients, and yawning was the most frequent etiological factor. Conservative treatment methods were used successfully in 86.4% of the patients managed. Two (66.7%) of the three patients who needed surgical treatment developed complications, while only one (5.3%) patient who was managed conservatively developed complications. Conclusion Temporomandibular joint dislocation appears to be associated with male sex, middle age, yawning, and low socio-economic status, although these observed relationships were not statistically significant. Non-invasive methods remain an effective treatment option in this environment in view of the low socio-economic status of the patients affected.

Fomete, Benjamin; Obiadazie, Athanasius Chukwudi; Idehen, Kelvin; Okeke, Uche

2014-01-01

244

Study methods, recruitment, socio-demographic findings and demographic representativeness in the OPPERA study  

PubMed Central

This paper describes methods used in the project “Orofacial Pain Prospective Evaluation and Risk Assessment” (OPPERA) and evaluates socio-demographic characteristics associated with temporomandibular disorders (TMD) in the OPPERA case-control study. Representativeness was investigated by comparing socio-demographic profiles of OPPERA participants with population census profiles of counties near study sites and by comparing age- and gender-associations with TMD in OPPERA and the 2007-09 US National Health Interview Survey. Volunteers aged 18-44 years were recruited at four US study sites: 3,263 people without TMD were enrolled into the prospective cohort study; 1,633 of them were selected as controls for the baseline case-control study. Cases were 185 volunteers with examiner-classified TMD. Distributions of some demographic characteristics among OPPERA participants differed from census profiles, although there was less difference in socio-economic profiles. Odds of TMD was associated with greater age in this 18-44 year range; females had three times the odds of TMD as males; and relative to non-Hispanic-Whites, other racial groups had one-fifth the odds of TMD. Age- and gender-associations with chronic TMD were strikingly similar to associations observed in the US population. Assessments of representativeness in this demographically diverse group of community volunteers suggest that OPPERA case-control findings have good internal validity.

Slade, Gary D.; Bair, Eric; By, Kunthel; Mulkey, Flora; Baraian, Cristina; Rothwell, Rebecca; Reynolds, Maria; Miller, Vanessa; Gonzalez, Yoly; Gordon, Sharon; Ribeiro-Dasilva, Margarete; Lim, Pei Feng; Greenspan, Joel D; Dubner, Ron; Fillingim, Roger B; Diatchenko, Luda; Maixner, William; Dampier, Dawn; Knott, Charles; Ohrbach, Richard

2011-01-01

245

Demographics: Diversity in More Forms. Student Demographics, Now and the Future.  

ERIC Educational Resources Information Center

While demographic diversity among the student body has increased substantially over the past several decades, the academic, economic, and social diversity of students will play a greater part in upcoming staffing and faculty requirements at community colleges. Data from Tallahassee Community College (TCC), in Florida, from 1980 to 1994 indicate…

Windham, Patricia; And Others

246

History Trail  

NSDL National Science Digital Library

For some, becoming more interested in history may be somewhat of an uphill battle. Sometimes it may be due to preconceived notions about the way the subject was presented when they were young, and others may find the material a bit dry. This website offered by the BBC presents a variety of historical perspectives that are both engaging and informative, and as such, the site is well worth a look. The various sections address such powerful themes as "Church and State", "Victorian Britain", and "Conquest", which affords visitors the opportunity to learn about the nature of the Norman invasion in 1066. The "Local History" section is quite helpful as it teaches visitors how to explore their own communities through historical clues, documents, and visual evidence. Each section contains brief articles, activities, and quizzes that help flesh out the material.

247

Naval History  

NSDL National Science Digital Library

The world of naval history is quite vast, especially considering that it is linked to the earliest days of warfare and stretches back thousands of years. Designed by Gordon Smith, this particular site details the history of various national navies during the twentieth century, with a particular focus on the World Wars and other military actions. Not surprisingly, visitors to the site will want to take a look at the areas dedicated to the World Wars, as the coverage of the role of various navies is quite good here. In these sections, visitors can learn about the various ships used during each period and also look at the campaigns and battles by year and by month. There is also a rather touching section dedicated to Gordon Smith's father, George Smith, who was lost in the sinking of the HMS Charybdis off the Brittany coast on October 23rd, 1943.

248

Learning Histories  

Microsoft Academic Search

{Excerpt} How can we gauge the successes and failures of collective learning? How can the rest of the organization benefit from the experience? Learning histories surface the thinking, experiments, and arguments of actors who engaged in organizational change.\\u000aIn the corporate world, the precedence ascribed to individual learning can run counter to organizational learning, the process by which an organization

Olivier Serrat

2011-01-01

249

River history.  

PubMed

During the last half century, advances in geomorphology-abetted by conceptual and technical developments in geophysics, geochemistry, remote sensing, geodesy, computing and ecology-have enhanced the potential value of fluvial history for reconstructing erosional and depositional sequences on the Earth and on Mars and for evaluating climatic and tectonic changes, the impact of fluvial processes on human settlement and health, and the problems faced in managing unstable fluvial systems. PMID:22474674

Vita-Finzi, Claudio

2012-05-13

250

History Detectives  

NSDL National Science Digital Library

Thinking about detectives in general makes most people's minds wander to thoughts of those rugged personages of television dramas or to the world of literature, with a lot of mucking about in dark alleyways or the sordid world of upper-crust intrigue and deception. PBS has elected to turn that perception on its head with its new program, History Detectives. This 10-part series is devoted to "solving historical mysteries, searching out the true facts (and falsehoods) behind local folklore, family legends and interesting objects." On this site, visitors can learn about the team of detectives (which includes an auctioneer, an architecture history professor, and a sociology professor), view clips from the program, and most importantly, about their various techniques for sleuthing. What is even better is that the site also offers overviews into various techniques (such as investigating the history of a building and examining personal papers) that allow users to get out there and do their own sleuthing in their own communities.

251

Encyclopedia of Oklahoma History & Culture  

NSDL National Science Digital Library

The 46th state, Oklahoma, presents its unusual history with the online version of The Encyclopedia of Oklahoma History and Culture. The Encyclopedia was prepared by over 500 "university-based scholars and independent historians and scholars," and was a joint effort by The Oklahoma Historical Society and Oklahoma State University Library Electronic Publishing Center. Visitors can click on the "Table of Contents" link near the bottom of the homepage to "Browse Entries Alphabetically", "Browse Entries Chronologically", or "Browse Entries by Subject". Browsing via chronology introduces visitors to Oklahoma starting with the "Precontact Era", through the "Westward Expansion" and on to "Twentieth Century to Present". Subject categories include "African Americans", "Farming", "Military", and "Petroleum". When searching, visitors will be taken to the Electronic Publishing Center Search Page, so they will need to choose the specific collection, Encyclopedia of Oklahoma History and Culture, from the drop down box, to confine the search to the Encyclopedia.

252

The Encyclopedia of Cleveland History  

NSDL National Science Digital Library

Sponsored jointly by Case Western Reserve University and the Western Reserve Historical Society, this excellent online text offers hundreds of articles on the history of Cleveland. There are two categories of articles in the Encyclopedia, general entries -- short articles of 200 to 500 words -- and interpretive essays -- "longer articles of 500 to 4000 words that explore major topics in local history." Both feature numerous hypertext links to related entries as well as photographic images that can be expanded to full screen. (These images may also be examined in a separate gallery on-site.) The encyclopedia features an alphabetical as well as a subject index and can be searched by title, text, and subject. A Reader's Guide and a bicentennial timeline of Cleveland history are also offered as supplementary text. New articles are added on a regular basis.

1998-01-01

253

Demographic factors and playing variables in online computer gaming.  

PubMed

Despite the growing popularity of online game playing, there has been no primary survey of its players. Therefore, an online questionnaire survey was used to examine basic demographic factors of online computer game players who played the popular online game Everquest (i.e., gender, age, marital status, nationality, education level, occupation). The survey also examined playing frequency (i.e., amount of time spent playing the game a week), playing history (i.e., how long they had been playing the game, who they played the game with, whether they had ever gender swapped their game character), the favorite and least favorite aspects of playing the game, and what they sacrifice (if anything) to play the game. Results showed that 81% of online game players were male, and that the mean age of players was 27.9 years of age. For many players, the social aspects of the game were the most important factor in playing. A small minority of players appear to play excessively (over 80 h a week), and results suggest that a small minority sacrifice important activities in order to play (e.g., sleep, time with family and/or partner, work, or schooling). PMID:15331036

Griffiths, Mark D; Davies, Mark N O; Chappell, Darren

2004-08-01

254

Relationship of Demographic and Health Factors to Cognition in Older Adults in the ACTIVE Study  

PubMed Central

Objective Examine the relationship of demographics and health conditions, alone and in combination, on objective measures of cognitive function in a large sample of community-dwelling older adults. Method Baseline data from 2782 participants in the ACTIVE study were used to examine relationships of demographics and health conditions with composite scores of memory, reasoning, and speed of processing. Results Younger age, increased education, and white race were independently associated with better performance in each cognitive domain after adjusting for gender and health conditions. Male gender, diabetes, and suspected clinical depression were associated with poorer cognitive functioning; suspected clinical depression was associated with lower reasoning and diabetes and history of stroke with slower speed of processing. Discussion Age, education, and race are consistently associated with cognitive performance in this sample of older community-dwelling adults. Diabetes, stroke, and suspected clinical depression had independent but weaker affects on cognition.

Rexroth, Daniel F.; Tennstedt, Sharon L.; Jones, Richard; Guey, Lin T.; Rebok, George W.; Marsiske, Michael; Xu, Yan; Unverzagt, Frederick W.

2013-01-01

255

Demographic, Maltreatment, and Neurobiological Correlates of PTSD Symptoms in Children and Adolescents  

PubMed Central

Objective?To examine the relationships of demographic, maltreatment, neurostructural and neuropsychological measures with total posttraumatic stress disorder (PTSD) symptoms.?Methods?Participants included 216 children with maltreatment histories (N = 49), maltreatment and PTSD (N = 49), or no maltreatment (N = 118). Participants received diagnostic interviews, brain imaging, and neuropsychological evaluations.?Results?We examined a hierarchical regression model comprised of independent variables including demographics, trauma and maltreatment-related variables, and hippocampal volumes and neuropsychological measures to model PTSD symptoms. Important independent contributors to this model were SES, and General Maltreatment and Sexual Abuse Factors. Although hippocampal volumes were not significant, Visual Memory was a significant contributor to this model.?Conclusions?Similar to adult PTSD, pediatric PTSD symptoms are associated with lower Visual Memory performance. It is an important correlate of PTSD beyond established predictors of PTSD symptoms. These results support models of developmental traumatology and suggest that treatments which enhance visual memory may decrease symptoms of PTSD.

Hooper, Stephen R.; Woolley, Donald P.; Shenk, Chad E.

2010-01-01

256

Earliest recollections of childhood: a demographic analysis.  

PubMed

A theory has recently been advanced which proposes that the development autobiographical recollection is shaped by a child's participation in discussions of events with adults (e.g. Nelson, 1988; Snow, 1990). A logical prediction of the theory is that demographic factors related to the nature of linguistic environments might be associated with differences in the development of autobiographical recollection. Four questionnaire studies that test this prediction are presented. The results, on a total of 768 subjects, show that the age of earliest memory increases across birth order, is slightly earlier for females than for males, and is earlier for Caucasians than for Asians. These findings are discussed in light of previous research showing that parents interact and talk more with first-borns and with girls, and in light of differences between Western and Asian cultures in socialization goals and the significance of autobiography in the development of self-concept. PMID:7924199

Mullen, M K

1994-07-01

257

Globally coupled chaotic maps and demographic stochasticity.  

PubMed

The effect of noise on a system of globally coupled chaotic maps is considered. Demographic stochasticity is studied since it provides both noise and a natural definition for extinction. A two-step model is presented, where the intrapatch chaotic dynamics is followed by a migration step with global dispersal. The addition of noise to the already chaotic system is shown to dramatically change its behavior. The level of migration in which the system attains maximal sustainability is identified. This determines the optimal way to manipulate a fragmented habitat in order to conserve endangered species. The quasideterministic dynamics that appears in the large N limit of the stochastic system is analyzed. In the clustering phase, the infinite degeneracy of deterministic solutions emerges from the single steady state of the stochastic system via a mechanism that involves an almost defective Markov matrix. PMID:20365819

Kessler, David A; Shnerb, Nadav M

2010-03-01

258

Cognitive age: demographic and psychographic dimensions.  

PubMed

This empirical study, based on a random self-report mail survey, explored perceptions of age among mature Americans aged 60+. Respondents were members of a systematic probability sample located in the Mid Atlantic region. Two inner-age dimensions were considered: the first, Cognitive Age, is a measure of self-perceived age and assesses a person's "actual" age-role self-concept; the second, entitled Youthfulness, is a new measure of youth scored by what percentage a respondent's Age-of-Birth is greater than his or her Cognitive Age (Chronological Age/Cognitive Age). The study first explored the relationships between the age variables, and then, through Multivariate Analyses of Variance (MANOVAs), the associations between four trait-sets (demographics, health, Quality of Life, and psychographic traits) and the two inner-age dimensions. PMID:10105779

Barak, B; Rahtz, D R

1990-01-01

259

The Demographics of Women in Astronomy  

NASA Astrophysics Data System (ADS)

To assess the status of women in astronomy we need data. How many women are astronomers? How does this percentage change with professional level? Do women have an advantage over men in hiring or other professional opportunities, or do men have the advantage, or is the playing field level? Using recent STScI and AAS surveys, I report the gender demographics in U.S. astronomy departments in 1999. Roughly 1/4 of astronomy graduate students are women, and this percentage decreases with rank, to 6% at the full professor level. Comparing to similar data from 1992, it appears that women fall behind men at the first transition, from graduate student to postdoc, but then keep pace with men in moving to faculty positions. (There is no sign that women advance more easily than men.) Interestingly, the percentage of women is slighly higher in the larger, better known institutions than in the profession as a whole.

Urry, M.; Marvel, K. B.; Blacker, B.

1999-12-01

260

The History of the Christensen Mandibular and TMJ Alloplastic Reconstruction  

Microsoft Academic Search

Objective. To inform the reader of the history of the Christensen mandibular and temporomandibular joint devices and the usefulness of the more recent generation of devices in the typical and atypical temporomandibular joint patient. Methods. The larger amount of data will involve the younger female patient who represents some 88% to 90% of patients with early to late TMJ disease

Robert W. Christensen

261

Volcanic Histories  

NSDL National Science Digital Library

To prepare for this in-class problem, students should have read about volcanism in their introductory text. Specifically they will need to know the types of volcanoes, the characteristics of volcanic products, such as lava flows of different silica compositions, tephra, lahars, and pyroclastic flows. Students should be able to connect the types of activity of a volcano to its type, such as composite volcanoes having abundant tephra, with some lava flows, while a shield volcano may have less tephra and more low viscosity lava flows. This activity is similar to the process used by geoscientists to evaluate the history and hazards of a volcano.

Filson, Robert H.

262

Geologic History  

NSDL National Science Digital Library

This unit introduces younger students to the concept of relative versus absolute time and how geologists determine the age of geologic events and features. Topics include the laws that determine relative age (superposition, cross-cutting relationships, included fragments, and others), and how to re-construct the geologic history of an area using these relationships. There is also information on geologic correlation and the use of index fossils to determine relative age. The section on absolute time discusses some ways of measurement (tree rings, radioactive dating) and introduces the concepts of natural selection and mass extinctions. A vocabulary and downloadable, printable student worksheets are provided.

Medina, Philip

2010-09-03

263

History Fun  

NSDL National Science Digital Library

Games and other fun information about history. The Battle of the Atlantic Game Defeat the U-boats and guide your convoy to safety The Battle of Hastings Game Discover the tactics and try putting them into practice Gladiator: Dressed to Kill Prepare a gladiator for battle in the arena of death Viking Quest Build a ship, loot a monastery and claim your prize Pyramid Challenge Complete the construction of the pharaoh\\'s tomb Mummy Maker Prepare the body of Ramose, officer to the king, for ...

Thatcher, Ms.

2006-10-17

264

Active rigidity joint  

NASA Astrophysics Data System (ADS)

Unimorph active rigidity joints, constructed from Shape Memory Alloy and Shape Memory Polymer and capable of bending actuation, are reported in this work. An embedded aluminum shim was added to each joint as a structural element to facilitate actuation. Joints were actuated using ohmic Tri-Phase and pulse heating processes with different results. It appeared that openloop position control could be achieved using pulse heating. Actuator improvements and future experiments are proposed.

Geeng, Franklin; Manzo, Justin; Garcia, Ephrahim

2010-03-01

265

Evaluating the importance of demographic connectivity in a marine metapopulation.  

PubMed

Recently researchers have gone to great lengths to measure marine metapopulation connectivity via tagging, genetic, and trace-elemental fingerprinting studies. These empirical estimates of larval dispersal are key to assessing the significance of metapopulation connectivity within a demographic context, but the life-history data required to do this are rarely available. To evaluate the demographic consequences of connectivity we constructed seasonal, size-structured metapopulation matrix models for two species of mytilid mussel in San Diego County, California, USA. The self-recruitment and larval exchange terms were produced from a time series of realized connectivities derived from trace-elemental fingerprinting of larval shells during spring and fall from 2003 to 2008. Both species exhibited a strong seasonal pattern of southward movement of recruits in spring and northward movement in fall. Growth and mortality terms were estimated using mark-recapture data from representative sites for each species and subpopulation, and literature estimates of juvenile mortality. Fecundity terms were estimated using county-wide settlement data from 2006-2008; these data reveal peak reproduction and recruitment in fall for Mytilus californianus, and spring for M. galloprovincialis. Elasticity and life-stage simulation analyses were employed to identify the season- and subpopulation-specific vital rates and connectivity terms to which the metapopulation growth rate (lambda) was most sensitive. For both species, metapopulation growth was most sensitive to proportional changes in adult fecundity, survival and growth of juvenile stages, and population connectivity, in order of importance, but relatively insensitive to adult growth or survival. The metapopulation concept was deemed appropriate for both Mytilus species as exchange between the subpopulations was necessary for subpopulation persistence. However, highest metapopulation growth occurred in years when a greater proportion of recruits was retained within the predominant source subpopulation. Despite differences in habitat and planktonic duration, both species exhibited similar overall metapopulation dynamics with respect to key life stages and processes. However, different peak reproductive periods in an environment of seasonal current reversals led to different regional (subpopulation) contributions to metapopulation maintenance; this result emphasizes the importance of connectivity analysis for spatial management of coastal resources. PMID:22073788

Carson, Henry S; Cook, Geoffrey S; López-Duarte, Paola C; Levin, Lisa A

2011-10-01

266

WTO History Project  

NSDL National Science Digital Library

A joint project of the University of Washington's (UW's) Harry Bridges Center for Labor Studies and the University Library, the WTO History Project focuses on the history-making protests of late 1999 in Seattle during the World Trade Organization (WTO) Ministerial meetings. A particularly groovy and educational highlight of this Website is the database of fliers, posters, notes, letters, etc. that the Manuscripts, Special Collections and University Archives Division of the UW Libraries makes Internet-accessible using CONTENTdm, a multimedia database developed at the UW. "CONTENTdm allows users to create customized searches of the collection and for high-quality digital reproductions to be viewed online, enabling some research to be conducted without visiting the collection." Visitors to the WTO History Project Website will also find a timeline of events prior to and during the 1999 protests in Seattle, including locations and sponsors, and a chart of organizations (with contact information) that were vocal in their opposition to the WTO, along with a list of registered WTO meeting attendees (MS Excel). In addition, this site features a page of interview transcripts with words from more than 80 organizers of and participants in the Seattle protests (.pdf). Organizations represented here include the Industrial Workers of the World, People for Fair Trade, the AFL-CIO, and the Sierra Club, to name just a few. This is a fantastic resource for students looking for primary texts dealing with labor and globalization issues or anyone wanting to learn more about the groups and individuals involved in the WTO protests. This site is still being developed, so check back often.

2001-01-01

267

Tuberculosis of bilateral first costotransverse joints.  

PubMed

Involvement of posterior spine constitutes to 1-6% of the cases of spinal tuberculosis (TB). To the best of our knowledge, TB of costotransverse joints has only been reported once in the literature. The purpose of this study is to describe a case of TB arthritis of costotransverse joints. A 22-year-old immunocompetent patient presented with a 3-month history of pain in the neck and upper back along with a swelling on the left side of the base of the neck. On performing an MRI of the cervicodorsal spine, there was evidence of destructive collections at the bilateral first and right-sided second costotransverse joints. The patient was diagnosed as a case of tubercular pathology and was managed successfully with antitubercular chemotherapy. PMID:23907973

Gupta, Mayank; Jain, Vijay Kumar; Naik, Ananta Kumar; Arya, Rajendera Kumar

2013-01-01

268

Joint hypermobility in adults referred to rheumatology clinics.  

PubMed Central

Joint hypermobility is a rarely recognised aetiology for focal or diffuse musculoskeletal symptoms. To assess the occurrence and importance of joint hypermobility in adult patients referred to a rheumatologist, we prospectively evaluated 130 consecutive new patients for joint hypermobility. Twenty women (15%) had joint hypermobility at three or more locations (greater than or equal to 5 points on a 9 point scale). Most patients with joint hypermobility had common musculoskeletal problems as the reason for referral. Two patients referred with a diagnosis of rheumatoid arthritis were correctly reassigned a diagnosis of hypermobility syndrome. Three patients with systemic lupus erythematosus had diffuse joint hypermobility. There was a statistically significant association between diffuse joint hypermobility and osteoarthritis. Most patients (65%) had first degree family members with a history of joint hypermobility. These results show that joint hypermobility is common, familial, found in association with common rheumatic disorders, and statistically associated with osteoarthritis. The findings support the hypothesis that joint hypermobility predisposes to musculoskeletal disorders, especially osteoarthritis.

Bridges, A J; Smith, E; Reid, J

1992-01-01

269

Thanksgiving History  

NSDL National Science Digital Library

Located at the Plimoth Plantation Web site, this collection of material related to the First Thanksgiving will be of great interest to those seeking to learn more about the facts and myths surrounding this famous event in American history. While most of the factual information about this meal comes from first-hand accounts written by William Bradford and Edward Winslow, these accounts are best understood by also studying household traditions, cooking techniques, and religious practices. The site consists primarily of brief essays that elucidate these various nuances of this legendary meal, including pieces on who exactly was in attendance at the 1621 First Thanksgiving, first-hand accounts about the meal, the bill of fare at the meal, and a piece that dispels the popular myth that popcorn was served at this meal. Perhaps the best part of the site are the modern recipe equivalents for the dishes served at the First Thanksgiving, including roast fowl, seethed cod, and hominy pudding.

270

Mapping History  

NSDL National Science Digital Library

Queen's tantrums? Children's puzzles? Those might not be the first things to come to mind when thinking about maps, but when one is considering the British LibraryâÂÂs online Mapping History exhibit, both those curious subjects and others are definitely present. Given that the Library has thousands of maps spanning the known world, this collection helps remind users "there is often more to a map than meets the eye." The collection is divided into four areas, including "Worlds at war" and "Wealth and poverty". Each section contains four to seven maps along with a brief essay that explains the importance of each document. Perhaps the most delightful section is titled "Deception, lies, and made-up lands". Here visitors can wander across a Chinese map of the world from 1644 and a map of Wellington in New Zealand from 1840 that gives the city an orderly appearance that bore only a partial resemblance to actual conditions on the ground.

2006-01-01

271

History Cooperative  

NSDL National Science Digital Library

A project of the American Historical Association (AHA), the Organization of American Historians (OAH), the University of Illinois Press, and the National Academy Press, this site currently offers index and abstract access to issues of the American Historical Review and the Journal of American History. Full text access is restricted to members of the AHA and OAH, and to institutions that subscribe to the print versions. The site also hosts special features that will remain free to all. One example of this material is the multimedia essay, "Los Angeles and the Problem of Urban Historical Knowledge," which employs animated maps, photos, and other visual materials. Another example of this content is a searchable online version of the fourteen-volume Booker T. Washington Papers originally published by the University of Illinois Press. The volumes are presented in an adapted version of the National Academy Press's Open Book framework and may be easily browsed, printed, and searched down to the page level.

272

Epidemiology and demographics of aggressive periodontitis.  

PubMed

Epidemiologic studies of aggressive periodontitis have used different study designs and a range of examination methods and case definitions, and this greatly complicates the study of disease prevalence in populations. The wide range of disease case definitions, in particular, profoundly impacts the reported rate of disease, and the use of a standard disease definition is strongly recommended. Surveys of aggressive periodontitis that use only clinical examinations, without radiographic examination to confirm the presence of a distinctive pattern of tissue loss, may overestimate the prevalence of this disease, particularly when a low threshold of attachment loss is used. The prevalence of aggressive periodontitis varies significantly between populations, and differences in race/ethnicities seem to be a key factor. Studies consistently show that aggressive periodontitis is most prevalent in Africa and in populations of African descent and is least prevalent in Caucasians in Europe and North America. Among children and young adults the prevalence of this disease is higher in older than in younger age groups. Most studies show comparable disease prevalence in male and female subjects. These findings show that aggressive periodontitis is a significant health problem in certain populations. This review also highlights a lack of information on the epidemiology and demographics of this disease in many parts of the world, particularly in Asia and Africa. Epidemiologic studies of aggressive periodontitis in high-risk populations are important and could provide vital data on the determinants of this disease, and this information is needed for the establishment of effective health-promotion measures. PMID:24738585

Susin, Cristiano; Haas, Alex N; Albandar, Jasim M

2014-06-01

273

Tape Joint Stiffness.  

National Technical Information Service (NTIS)

This redport evaluates the stiffness for a standard tape-joint structural connection. This stiffness is frequently necessary when modeling a structure (e.g., a shock model). In general, for a standard cylindrical tape joint, the stiffness is 1.2 times gre...

R. P. Rechard

1986-01-01

274

Behavior of jointed pipelines  

Microsoft Academic Search

Experimental data on the axial, bending and torsional behavior of ductile cast iron pipes with rubber gasket joints is presented. Analytical expressions are provided which predict the resistance mechanisms and behavior of the joints. The bending mechanism is found to be quite different from the axial and torsional mechanism. By repeating the tests in a specially designed soil box, the

Singhal

1984-01-01

275

Investigation of joint disease  

Microsoft Academic Search

The role of nuclear medicine in the diagnosis and management of the major arthropathies is critically reviewed, with particular reference to osteoarthritis, rheumatoid and similar forms of arthritis, ankylosing spondylitis, non-specific back pain, gout, the neuropathic joint, avascular necrosis, infection and the consequences of prosthetic joint insertion. Attention is drawn both to practical applications and deficiencies in current techniques and

M. V. Merrick

1992-01-01

276

Bone and joint infections  

Microsoft Academic Search

Infections involving bone and joint are a significant cause of morbidity and mortality. They can result in prolonged hospital stays, long courses of systemic antibiotics and frequently will require surgical intervention. In this review we will cover the commonest infections seen clinically. We have also chosen to divide the review into two sections; infections involving native tissue\\/joints and infections relating

Tom Darton; Robert Townsend

2010-01-01

277

Campylobacter prosthetic joint infection.  

PubMed

A 75-year-old man was diagnosed with probable Campylobacter jejuni prosthetic knee infection after a diarrheal illness. Joint aspirate and operative cultures were negative, but PCR of prosthesis sonicate fluid was positive, as was stool culture. Nineteen additional cases of Campylobacter prosthetic joint infection reported in the literature are reviewed. PMID:24523462

Vasoo, Shawn; Schwab, Jeramy J; Cunningham, Scott A; Robinson, Trisha J; Cass, Joseph R; Berbari, Elie F; Walker, Randall C; Osmon, Douglas R; Patel, Robin

2014-05-01

278

Prosthetic Elbow Joint.  

National Technical Information Service (NTIS)

An artificial manually positionable elbow joint for use in an upper extremity, above-elbow, prosthetic which provides a locking feature that is easily controlled by the wearer is described. The instant elbow joint is very strong and durable to withstand t...

B. Weddendorf

1992-01-01

279

Joint warfare system (JWARS)  

Microsoft Academic Search

The Joint Warfare System (JWARS) is a campaign-level model of military operations that is currently being developed under contract by the Office of the Secretary of Defense (OSD) for use by OSD, the Joint Staff, the Services, and the War fighting Commands. The behavior of military forces can be simulated from ports of embarkation through to their activities in combat.

A. Simlote

2003-01-01

280

General joint laxity  

Microsoft Academic Search

General joint laxity is measured with the hyperextensometer, and by analyzing the values obtained in a group of European subjects norm curves are drawn up related to age and sex. The values found in various orthopedic diseases are put into these curves, and the importance of general joint laxity is discussed.

L. Dubs; N. Gschwend

1988-01-01

281

Joint Seal Materials.  

National Technical Information Service (NTIS)

Three major experimental field installations of approximately 7 types of joint sealing materials were used to compare and evaluate the products of numerous sealant manufacturers. The sealants were placed in contraction joints (3/8 in. x 2 in.) which were ...

J. G. F. Hiss J. R. Lambert W. M. McCarty

1968-01-01

282

Superconducting cable joint resistance  

SciTech Connect

This paper reports on results of a parametric study of the 4.2 K resistance of lap joints between two 27-strand cables of multifilamentary Nb{sub 3}Sn wire. All joints were between ribbon terminations made rolling copper-encapsulated cable ends flat. Resistances as functions of current were inferred from current decay time constants of cable-in-conduit conductor loops connected by the joints. The resistances of twenty three samples were measured (range of 0.2 to 3 n{Omega}). It was found that lap joint resistance was a function of current. The influences of solder versus no solder, solder thickness, indium versus tin-lead, ribbon surface oxidation, solder flux, cable twist pitch, wire chrome plating, clamping pressure during heat treatment, ribbon aspect ratio, and joint length are reported.

Herbelot, O.; Steeves, M.M.; Hoening, M.O. (Massachusetts Inst. of Tech., Cambridge, MA (United States). Plasma Fusion Center)

1991-03-01

283

Applying demographic analysis in affirmative action disputes: An instructional case  

Microsoft Academic Search

This instructional case study illustrates applications of demographic concepts, data, and techniques in evaluating affirmative action goals for equalizing employment opportunity. Courts of law addressing employment discrimination disputes need an accurate picture of each minority group's proportion in a pool of prospective employees. The demographic and socioeconomic factors conditioning those proportions vary from place to place. In the situation examined

Peter A. Morrison

1998-01-01

284

Demographic Factors in Adult and Continuing Education. A Keynote Address.  

ERIC Educational Resources Information Center

The basic premise of the book, "Demographic Factors in Adult and Continuing Education," (on which this keynote address is based) is that adult and continuing education are irrelevant, immaterial, and inconsequential unless grounded in social reality. The book identifies more than 1 million demographic factors in the 8 Mountain Plains States. This…

Jelinek, James J.

285

Some Emerging Demographic Issues on Australia's Teaching Academic Workforce  

ERIC Educational Resources Information Center

Like other OECD nations, Australia is facing a crisis in the academic staff of its universities over the next two decades. This is a function of several factors, among which demographic elements are especially significant. The academic workforce of Australia is characterized by three distinct demographic features--age heaping, a concentration in…

Hugo, Graeme

2005-01-01

286

Examining the Impact of Demographic Factors on Air Pollution  

Microsoft Academic Search

This study adds to the emerging literature examining empirically the link between population size, other demographic factors and pollution. We contribute by using more reliable estimation techniques and examine two air pollutants. By considering sulfur dioxide, we become the first study to explicitly examine the impact of demographic factors on a pollutant other than carbon dioxide at the cross-national level.

Matthew A. Cole; Eric Neumayer

2004-01-01

287

Science Achievement, Class Size, and Demographics: The Debate Continues.  

ERIC Educational Resources Information Center

Examined the relationship between school system financial and demographic data and student achievement in the science section of the 1998 Tennessee statewide Terra Nova tests. Results indicate that while many schools had science scale score achievement higher than expected based on system demographics, others should examine a variety of…

Miller-Whitehead, Marie

2001-01-01

288

Demographic Transition and Economic Opportunity: The Case of Jordan.  

National Technical Information Service (NTIS)

To take economic advantage of the extensive demographic transition expected to take place in Jordan over the coming 40 years, that country's decision makers need to create policies that appropriately deal with demographic change. To do so, they need to be...

D. E. Bloom D. Canning A. K. Nandakumar J. Sevilla K. Huzarski D. Levy M. Bhawalkar

2001-01-01

289

A Classroom Activity to Illustrate the Demographic Transition  

ERIC Educational Resources Information Center

A discussion of the Demographic Transition is included in many Environmental Biology or Environmental Science classes. The Demographic Transition occurs as a nation becomes more urban and wealthy, and was widely observed in the twentieth century. The phenomenon includes decreasing family size (fewer children) across generations. In this classroom…

Weihe, Paul

2006-01-01

290

The Demographic Transition: Stages, Patterns, and Economic Implications  

Microsoft Academic Search

This book examines the basic mechanisms behind the modernization of demographic behaviour. The author has marshalled an impressive amount of statistical material relating to 67 countries, half of them less developed, and covering the period 1720-1984. The whole sweep of western demographic experience is dealt with comprehensively and impartially, and though technically sophisticated, the book also covers issues of interpretation

Jean-Claude Chesnais

1992-01-01

291

Demographic Transitions and Economic Miracles in Emerging Asia  

Microsoft Academic Search

The demographic transition a change from high to low rates of mortality and fertility has been more dramatic in East Asia during this century than in any other region or historical period. By introducing demographic variables into an empirical model of economic growth, this essay shows that this transition has contributed substantially to East Asia's so-called economic miracle. The 'miracle'

David E. Bloom; Jeffrey G. Williamson

1997-01-01

292

The Demographic Transition and the Emergence of Sustained Economic Growth  

Microsoft Academic Search

The demographic transition that swept the world in the course of the last century has been identified as one of the prime forces in the transition from stagnation to growth. The unprecedented increase in population growth during the early stages of industrialization was ultimately reversed and the demographic transition brought about a significant reduction in fertility rates and population growth

Oded Galor

2005-01-01

293

China's Demographic Challenge Requires an Integrated Coping Strategy  

ERIC Educational Resources Information Center

China has entered into a new stage of demographic dynamics whereby population-related challenges are more complicated than ever before. The current one-child policy should be modified. However, the anticipated impacts of such a policy change should not be over-exaggerated. China's demographic challenge requires an integrated coping strategy.…

Peng, Xizhe

2013-01-01

294

Demographic Faultlines: A Meta-Analysis of the Literature  

ERIC Educational Resources Information Center

We propose and test a theoretical model focusing on antecedents and consequences of demographic faultlines. We also posit contingencies that affect overall team dynamics in the context of demographic faultlines, such as the study setting and performance measurement. Using meta-analysis structural equation modeling with a final data set consisting…

Thatcher, Sherry M. B.; Patel, Pankaj C.

2011-01-01

295

Christian Schools and Demographic Change: Two Case Studies  

ERIC Educational Resources Information Center

This article explores how two Christian school systems have responded to neighborhood demographic change. Researchers conducted interviews, attended meetings, and reviewed documents to explore two case studies--one of a school struggling to redefine its identity, purpose, and vision in response to demographic change, and another school that has…

Huyser, Mackenzi; Boerman-Cornell, Bill; DeBoer, Kendra

2011-01-01

296

The Impact of Extrinsic Demographic Factors on Cantonese Speech Acquisition  

ERIC Educational Resources Information Center

This study modeled the associations between extrinsic demographic factors and children's speech acquisition in Hong Kong Cantonese. The speech of 937 Cantonese-speaking children aged 2;4 to 6;7 in Hong Kong was assessed using a standardized speech test. Demographic information regarding household income, paternal education, maternal education,…

To, Carol K. S.; Cheung, Pamela S. P.; McLeod, Sharynne

2013-01-01

297

Senior Officer Oral History Program Project Handlist. [Revised.  

ERIC Educational Resources Information Center

The Senior Officer Oral History Program (SOOHP) is sponsored jointly by the U.S. Army War College and the U.S. Army Military History Institute, as an educational service. As of 1992, this program includes over 2,000 hours of taped interviews and 100,000 transcribed pages covering 900 military personalities and special topics. This document is a…

Army War Coll., Carlisle Barracks, PA.

298

Demographic processes: past, present and future - selected issues  

NASA Astrophysics Data System (ADS)

This papers refers to demographic processes in the period from the 19th century through to the present and tries to define what they will look like in the future. Demographic trends i.a. relating to fertility, mortality, migrations, the process of family-union-household formation and dissolution, and the process of population ageing, are described by the concepts of demographic transformations: first, second and third. The transformation of demographic trends has coexisted and will coexist with globalization processes, though the scope of the mutual influence changes over time. Despite the fact that it takes place in various geographical regions, the transformation of demographic trends is characterised by high cultural diversity and socio-economic development.

Fr?tczak, Ewa Zofia

2013-01-01

299

Handbook on dynamics of jointed structures.  

SciTech Connect

The problem of understanding and modeling the complicated physics underlying the action and response of the interfaces in typical structures under dynamic loading conditions has occupied researchers for many decades. This handbook presents an integrated approach to the goal of dynamic modeling of typical jointed structures, beginning with a mathematical assessment of experimental or simulation data, development of constitutive models to account for load histories to deformation, establishment of kinematic models coupling to the continuum models, and application of finite element analysis leading to dynamic structural simulation. In addition, formulations are discussed to mitigate the very short simulation time steps that appear to be required in numerical simulation for problems such as this. This handbook satisfies the commitment to DOE that Sandia will develop the technical content and write a Joints Handbook. The content will include: (1) Methods for characterizing the nonlinear stiffness and energy dissipation for typical joints used in mechanical systems and components. (2) The methodology will include practical guidance on experiments, and reduced order models that can be used to characterize joint behavior. (3) Examples for typical bolted and screw joints will be provided.

Ames, Nicoli M.; Lauffer, James P.; Jew, Michael D.; Segalman, Daniel Joseph; Gregory, Danny Lynn; Starr, Michael James; Resor, Brian Ray

2009-07-01

300

Conservation biology for suites of species: Demographic modeling for Pacific island kingfishers  

USGS Publications Warehouse

Conservation practitioners frequently extrapolate data from single-species investigations when managing critically endangered populations. However, few researchers initiate work with the intent of making findings useful to conservation efforts for other species. We presented and explored the concept of conducting conservation-oriented research for suites of geographically separated populations with similar natural histories, resource needs, and extinction threats. An example was provided in the form of an investigation into the population demography of endangered Micronesian kingfishers (Todiramphus cinnamominus). We provided the first demographic parameter estimates for any of the 12 endangered Pacific Todiramphus species, and used results to develop a population projection matrix model for management throughout the insular Pacific. Further, we used the model for elasticity and simulation analyses with demographic values that randomly varied across ranges that might characterize congener populations. Results from elasticity and simulation analyses indicated that changes in breeding adult survival exerted the greatest magnitude of influence on population dynamics. However, changes in nestling survival were more consistently correlated with population dynamics as demographic rates were randomly altered. We concluded that conservation practitioners working with endangered Pacific kingfishers should primarily focus efforts on factors affecting nestling and breeder survival, and secondarily address fledgling juveniles and helpers. Further, we described how the generalized base model might be changed to focus on individual populations and discussed the potential application of multi-species models to other conservation situations. ?? 2007 Elsevier Ltd. All rights reserved.

Kesler, D. C.; Haig, S. M.

2007-01-01

301

TESTING LIFE HISTORY CORRELATES OF INVASIVENESS USING CONGENERIC PLANT SPECIES  

Microsoft Academic Search

We used three congeneric annual thistles, which vary in their ability to invade California (USA) annual grasslands, to test whether invasiveness is related to differences in life history traits. We hypothesized that populations of these summer-flowering Centaurea species must pass through a demographic gauntlet of survival and reproduction in order to persist and that the most invasive species (C. solstitialis)

John D. Gerlach; Kevin J. Rice

2003-01-01

302

MISR JOINT_AS Data  

MISR Data and Information Joint Aerosol Product (JOINT_AS) The MISR Level 3 Products are ... campaigns at daily and monthly time scales. The Joint Aerosol product provides a monthly global statistical summary of MISR Level 2 ...

2014-03-24

303

Cover For Duct Expansion Joint  

NASA Technical Reports Server (NTRS)

Size and shape of cover reduces stress and increases strength. Cover for expansion joints on duct-work seals tightly while accommodating movement of joint. Provides ample bonding area on both members of joint.

Brown, A. R.

1988-01-01

304

Demographic and Evolutionary Consequences of Selective Mortality: Predictions from an Eco-Genetic Model for Smallmouth Bass  

Microsoft Academic Search

We use an individual-based eco-genetic model to examine the demographic and evolutionary consequences of selective mortality on a species with parental care, the smallmouth bass Micropterus dolomieu. Our analyses are grounded in a long-term (1936-2003) empirical study of the dynamics of two populations that differ widely in both density and life history. The model we construct extends previous approaches by

Erin S. Dunlop; Brian J. Shuter; Ulf Dieckmann

2007-01-01

305

Phylogeography and demographic history of Babina pleuraden (Anura, Ranidae) in southwestern China.  

PubMed

Factors that determine genetic structure of species in southwestern China remain largely unknown. In this study, sequences of two mitochondrial genes (COI and cyt b) were determined to investigate the phylogeography and demography of Babina pleuraden, a pond frog endemic to southwestern China. A total of 262 individuals from 22 populations across the entire range of the species were collected. Our results indicate that B. pleuraden comprises five well-supported mitochondrial lineages roughly corresponding to five geographical areas. The phylogeographic structure of B. pleuraden has been shaped primarily by the unique regional responses of the Yunnan Plateau to the rapid uplift of the Qinghai-Tibetan Plateau occurred c. 2.5 Mya (B phrase of Qingzang Movement) and climatic oscillation during middle Pleistocene (c. 0.64-0.36 Mya), rather than by the paleo-drainage systems. The present wide distribution of the species has resulted from recent population expansion (c. 0.053-0.025 Mya) from multiple refugia prior to the Last Glacial Maximum, corresponding to the scenario of "refugia within refugia". PMID:22448286

Li, Zejun; Yu, Guohua; Rao, Dingqi; Yang, Junxing

2012-01-01

306

Whole-genome sequence variation, population structure and demographic history of the Dutch population.  

PubMed

Whole-genome sequencing enables complete characterization of genetic variation, but geographic clustering of rare alleles demands many diverse populations be studied. Here we describe the Genome of the Netherlands (GoNL) Project, in which we sequenced the whole genomes of 250 Dutch parent-offspring families and constructed a haplotype map of 20.4 million single-nucleotide variants and 1.2 million insertions and deletions. The intermediate coverage (?13×) and trio design enabled extensive characterization of structural variation, including midsize events (30-500 bp) previously poorly catalogued and de novo mutations. We demonstrate that the quality of the haplotypes boosts imputation accuracy in independent samples, especially for lower frequency alleles. Population genetic analyses demonstrate fine-scale structure across the country and support multiple ancient migrations, consistent with historical changes in sea level and flooding. The GoNL Project illustrates how single-population whole-genome sequencing can provide detailed characterization of genetic variation and may guide the design of future population studies. PMID:24974849

2014-08-01

307

Phylogeography and Demographic History of Babina pleuraden (Anura, Ranidae) in Southwestern China  

PubMed Central

Factors that determine genetic structure of species in southwestern China remain largely unknown. In this study, sequences of two mitochondrial genes (COI and cyt b) were determined to investigate the phylogeography and demography of Babina pleuraden, a pond frog endemic to southwestern China. A total of 262 individuals from 22 populations across the entire range of the species were collected. Our results indicate that B. pleuraden comprises five well-supported mitochondrial lineages roughly corresponding to five geographical areas. The phylogeographic structure of B. pleuraden has been shaped primarily by the unique regional responses of the Yunnan Plateau to the rapid uplift of the Qinghai-Tibetan Plateau occurred c. 2.5 Mya (B phrase of Qingzang Movement) and climatic oscillation during middle Pleistocene (c. 0.64–0.36 Mya), rather than by the paleo-drainage systems. The present wide distribution of the species has resulted from recent population expansion (c. 0.053–0.025 Mya) from multiple refugia prior to the Last Glacial Maximum, corresponding to the scenario of “refugia within refugia”.

Rao, Dingqi; Yang, Junxing

2012-01-01

308

The effects of Medieval dams on genetic divergence and demographic history in brown trout populations  

PubMed Central

Background Habitat fragmentation has accelerated within the last century, but may have been ongoing over longer time scales. We analyzed the timing and genetic consequences of fragmentation in two isolated lake-dwelling brown trout populations. They are from the same river system (the Gudenå River, Denmark) and have been isolated from downstream anadromous trout by dams established ca. 600–800 years ago. For reference, we included ten other anadromous populations and two hatchery strains. Based on analysis of 44 microsatellite loci we investigated if the lake populations have been naturally genetically differentiated from anadromous trout for thousands of years, or have diverged recently due to the establishment of dams. Results Divergence time estimates were based on 1) Approximate Bayesian Computation and 2) a coalescent-based isolation-with-gene-flow model. Both methods suggested divergence times ca. 600–800 years bp, providing strong evidence for establishment of dams in the Medieval as the factor causing divergence. Bayesian cluster analysis showed influence of stocked trout in several reference populations, but not in the focal lake and anadromous populations. Estimates of effective population size using a linkage disequilibrium method ranged from 244 to?>?1,000 in all but one anadromous population, but were lower (153 and 252) in the lake populations. Conclusions We show that genetic divergence of lake-dwelling trout in two Danish lakes reflects establishment of water mills and impassable dams ca. 600–800 years ago rather than a natural genetic population structure. Although effective population sizes of the two lake populations are not critically low they may ultimately limit response to selection and thereby future adaptation. Our results demonstrate that populations may have been affected by anthropogenic disturbance over longer time scales than normally assumed.

2014-01-01

309

Low worldwide genetic diversity in the killer whale (Orcinus orca): implications for demographic history  

Microsoft Academic Search

A low level of genetic variation in mammalian populations where the census population size is relatively large has been attributed to various factors, such as a naturally small effective population size, historical bottlenecks and social behaviour. The killer whale (Orcinus orca) is an abundant, highly social species with reduced genetic variation. We find no consistent geographical pattern of global diversity

A. Rus Hoelzel; Ada Natoli; Marilyn E. Dahlheim; Carlos Olavarria; Robin W. Baird; Nancy A. Black

2009-01-01

310

Demographic Characteristics, Phenomenology, Comorbidity, and Family History in 200 Individuals With Body Dysmorphic Disorder  

PubMed Central

The authors examined characteristics of body dysmorphic disorder in the largest sample for which a wide range of clinical features has been reported. The authors also compared psychiatrically treated and untreated subjects. Body dysmorphic disorder usually began during adolescence, involved numerous body areas and behaviors, and was characterized by poor insight, high comorbidity rates, and high rates of functional impairment, suicidal ideation, and suicide attempts. There were far more similarities than differences between the currently treated and untreated subjects, although the treated subjects displayed better insight and had more comorbidity.

Phillips, Katharine A.; Menard, William; Fay, Christina; Weisberg, Risa

2005-01-01

311

Gene flow and demographic history of leopards (Panthera pardus) in the central Indian highlands.  

PubMed

Gene flow is a critical ecological process that must be maintained in order to counteract the detrimental effects of genetic drift in subdivided populations, with conservation benefits ranging from promoting the persistence of small populations to spreading adaptive traits in changing environments. We evaluated historical and contemporary gene flow and effective population sizes of leopards in a landscape in central India using noninvasive sampling. Despite the dramatic changes in land-use patterns in this landscape through recent times, we did not detect any signs that the leopard populations have been through a genetic bottleneck, and they appear to have maintained migration-drift equilibrium. We found that historical levels of gene flow (mean m h = 0.07) were significantly higher than contemporary levels (mean m c = 0.03), and populations with large effective population sizes (Satpura and Kanha Tiger Reserves) are the larger exporters of migrants at both timescales. The greatest decline in historical versus contemporary gene flow is between pairs of reserves that are currently not connected by forest corridors (i.e., Melghat-Pench m h - m c = 0.063; and Kanha-Satpura m h - m c = 0.054). We attribute this reduction in gene flow to accelerated fragmentation and habitat alteration in the landscape over the past few centuries, and suggest protection of forest corridors to maintain gene flow in this landscape. PMID:24062803

Dutta, Trishna; Sharma, Sandeep; Maldonado, Jesús E; Wood, Thomas C; Panwar, Hemendra S; Seidensticker, John

2013-09-01

312

Demographic and phylogeographic histories of two venomous North American snakes of the genus Agkistrodon  

Microsoft Academic Search

Many studies have revealed that lineages currently inhabiting formerly glaciated areas were pushed into southern glacial refugia and have expanded into their modern range since the last glacial maximum. There have been few studies that compare the effects of glacial cycles on lineage diversification and historical demography in closely related species with overlapping ranges. In this study we compare phylogeographic

Timothy J. Guiher; Frank T. Burbrink

2008-01-01

313

Origin and demographic history of the endemic Taiwan spruce (Picea morrisonicola)  

PubMed Central

Taiwan spruce (Picea morrisonicola) is a vulnerable conifer species endemic to the island of Taiwan. A warming climate and competition from subtropical tree species has limited the range of Taiwan spruce to the higher altitudes of the island. Using seeds sampled from an area in the central mountain range of Taiwan, 15 nuclear loci were sequenced in order to measure genetic variation and to assess the long-term genetic stability of the species. Genetic diversity is low and comparable to other spruce species with limited ranges such as Picea breweriana, Picea chihuahuana, and Picea schrenkiana. Importantly, analysis using approximate Bayesian computation (ABC) provides evidence for a drastic decline in the effective population size approximately 0.3–0.5 million years ago (mya). We used simulations to show that this is unlikely to be a false-positive result due to the limited sample used here. To investigate the phylogenetic origin of Taiwan spruce, additional sequencing was performed in the Chinese spruce Picea wilsonii and combined with previously published data for three other mainland China species, Picea purpurea, Picea likiangensis, and P. schrenkiana. Analysis of population structure revealed that P. morrisonicola clusters most closely with P. wilsonii, and coalescent analyses using the program MIMAR dated the split to 4–8 mya, coincidental to the formation of Taiwan. Considering the population decrease that occurred after the split, however, led to a much more recent origin.

Bodare, Sofia; Stocks, Michael; Yang, Jeng-Chuann; Lascoux, Martin

2013-01-01

314

Adolescent Sexual OffendersDemographics, Criminal and Sexual Histories, and Recommendations for Reducing Future Offenses  

Microsoft Academic Search

Sexual aggression is a serious and widespread problem in our society. Over the past 15 years considerable effort has been directed toward educating society about the problem and addressing the needs of victims of sexual crimes. Research efforts have focused on both adult and child victims and to a lesser extent on adult sexual offenders. Only recently have any research

JUDITH V. BECKER; JERRY CUNNINGHAM-RATHNER; MEG S. KAPLAN

1986-01-01

315

Appendicular joint dislocations.  

PubMed

This study defines the incidence and epidemiology of joint dislocations and subluxations of the appendicular skeleton. All patients presenting acutely to hospital with a dislocation or subluxation of the appendicular skeleton from a defined population were included in the study. There were 974 dislocations or subluxations over one year between the 1st November 2008 and the 31st October 2009. There was an overall joint dislocation incidence of 157/10(5)/year (188/10(5)/year in males and 128/10(5)/year in females). Males demonstrated a bimodal distribution with a peak incidence of 446/10(5)/year at 15-24 years old and another of 349/10(5)/year in those over 90 years. Females demonstrate an increasing incidence from the seventh decade with a maximum incidence of 520/10(5)/year in those over 90 years. The most commonly affected joints are the glenohumeral (51.2/10(5)/year), the small joints of the hand (29.9/10(5)/year), the patellofemoral joint (21.6/10(5)/year), the prosthetic hip (19.0/10(5)/year), the ankle (11.5/10(5)/year), the acromioclavicular joint (8.9/10(5)/year) and the elbow (5.5/10(5)/year). Unlike fractures, dislocations are more common in the both the most affluent and the most socially deprived sections of the population. Joint disruptions are more common than previously estimated. PMID:23433660

Hindle, Paul; Davidson, Eleanor K; Biant, Leela C; Court-Brown, Charles M

2013-08-01

316

Pressure vessel flex joint  

NASA Technical Reports Server (NTRS)

An airtight, flexible joint is disclosed for the interfacing of two pressure vessels such as between the Space Station docking tunnel and the Space Shuttle Orbiter bulkhead adapter. The joint provides for flexibility while still retaining a structural link between the two vessels required due to the loading created by the internal/external pressure differential. The joint design provides for limiting the axial load carried across the joint to a specific value, a function returned in the Orbiter/Station tunnel interface. The flex joint comprises a floating structural segment which is permanently attached to one of the pressure vessels through the use of an inflatable seal. The geometric configuration of the joint causes the tension between the vessels created by the internal gas pressure to compress the inflatable seal. The inflation pressure of the seal is kept at a value above the internal/external pressure differential of the vessels in order to maintain a controlled distance between the floating segment and pressure vessel. The inflatable seal consists of either a hollow torus-shaped flexible bladder or two rolling convoluted diaphragm seals which may be reinforced by a system of straps or fabric anchored to the hard structures. The joint acts as a flexible link to allow both angular motion and lateral displacement while it still contains the internal pressure and holds the axial tension between the vessels.

Kahn, Jon B. (inventor)

1992-01-01

317

The Joint Confidence Level Paradox: A History of Denial  

NASA Technical Reports Server (NTRS)

This paper is intended to provide a reliable methodology for those tasked with generating price tags on construction (C0F) and research and development (R&D) activities in the NASA performance world. This document consists of a collection of cost-related engineering detail and project fulfillment information from early agency days to the present. Accurate historical detail is the first place to start when determining improved methodologies for future cost and schedule estimating. This paper contains a beneficial proposed cost estimating method for arriving at more reliable numbers for future submits. When comparing current cost and schedule methods with earlier cost and schedule approaches, it became apparent that NASA's organizational performance paradigm has morphed. Mission fulfillment speed has slowed and cost calculating factors have increased in 21st Century space exploration.

Butts, Glenn; Linton, Kent

2009-01-01

318

Case histories of successfully sealed expansion joints with polysulfide sealants  

SciTech Connect

In the late 1930s, a polysulfide based sealant was used to seal the fuel tanks for Pan American World Airways` China Clipper. This was the first use of an elastomeric sealant based on a synthetic polymer and is the first in a long list of installations for sealants based on the polysulfide polymer. The good resistance of polysulfide based sealants to petroleum products made them a natural to become the standard for virtually all aircraft sealants. Because of their good weathering resistance and elastomeric properties the construction market seemed to offer the next greatest opportunity. This paper will discuss applications and will show the versatility of these sealants to perform well in various environments.

Fiorillo, A.R. [Morton International, Woodstock, IL (United States)

1994-12-31

319

Case histories of successfully sealed expansion joints with polysulfide sealants  

Microsoft Academic Search

In the late 1930s, a polysulfide based sealant was used to seal the fuel tanks for Pan American World Airways` China Clipper. This was the first use of an elastomeric sealant based on a synthetic polymer and is the first in a long list of installations for sealants based on the polysulfide polymer. The good resistance of polysulfide based sealants

Fiorillo

1994-01-01

320

Compliant Joints For Robots  

NASA Technical Reports Server (NTRS)

Compliant joints devised to accommodate misalignments of tools and/or workpieces with respect to robotic manipulators. Has characteristics and appearance of both universal-joint and cable-spring-type flexible shaft coupling. Compliance derived from elastic properties of short pieces of cable. Compliance of joint determined by lengths, distances between, relative orientations, thickness of strands, number of strands, material, amount of pretwist, and number of short pieces of cable. Worm-drive mechanism used to adjust lengths to vary compliance as needed during operation.

Kerley, James J., Jr.

1990-01-01

321

Combining genetic and demographic data for prioritizing conservation actions: insights from a threatened fish species.  

PubMed

Prioritizing and making efficient conservation plans for threatened populations requires information at both evolutionary and ecological timescales. Nevertheless, few studies integrate multidisciplinary approaches, mainly because of the difficulty for conservationists to assess simultaneously the evolutionary and ecological status of populations. Here, we sought to demonstrate how combining genetic and demographic analyses allows prioritizing and initiating conservation plans. To do so, we combined snapshot microsatellite data and a 30-year-long demographic survey on a threatened freshwater fish species (Parachondrostoma toxostoma) at the river basin scale. Our results revealed low levels of genetic diversity and weak effective population sizes (<63 individuals) in all populations. We further detected severe bottlenecks dating back to the last centuries (200-800 years ago), which may explain the differentiation of certain populations. The demographic survey revealed a general decrease in the spatial distribution and abundance of P. toxostoma over the last three decades. We conclude that demo-genetic approaches are essential for (1) identifying populations for which both evolutionary and ecological extinction risks are high; and (2) proposing conservation plans targeted toward these at risk populations, and accounting for the evolutionary history of populations. We suggest that demo-genetic approaches should be the norm in conservation practices. We combined genetic and demographic data from a threatened freshwater fish species (Parachondrostoma toxostoma) at the river basin scale for conservation purposes. Genetic diversity and effective population sizes are very low, probably due to the strong genetic bottlenecks detected in this study. The species spatial distribution and abundance also decreased during the last decades. PMID:24567833

Paz-Vinas, Ivan; Comte, Lise; Chevalier, Mathieu; Dubut, Vincent; Veyssiere, Charlotte; Grenouillet, Gaël; Loot, Geraldine; Blanchet, Simon

2013-08-01

322

Influence of harvesting pressure on demographic tactics: Implications for wildlife management  

USGS Publications Warehouse

Demographic tactics within animal populations are shaped by selective pressures. Exploitation exerts additional pressures so that differing demographic tactics might be expected among populations with differences in levels of exploitation. Yet little has been done so far to assess the possible consequences of exploitation on the demographic tactics of mammals, even though such information could influence the choice of effective management strategies. Compared with similar-sized ungulate species, wild boar Sus scrofa has high reproductive capabilities, which complicates population management. Using a perturbation analysis, we investigated how population growth rates (??) and critical life-history stages differed between two wild boar populations monitored for several years, one of which was heavily harvested and the other lightly harvested. Asymptotic ?? was 1??242 in the lightly hunted population and 1??115 in the heavily hunted population, while the ratio between the elasticity of adult survival and juvenile survival was 2??63 and 1??27, respectively. A comparative analysis including 21 other ungulate species showed that the elasticity ratio in the heavily hunted population was the lowest ever observed. Compared with expected generation times of similar-sized ungulates (more than 6years), wild boar has a fast life-history speed, especially when facing high hunting pressure. This is well illustrated by our results, where generation times were 3??6years in the lightly hunted population and only 2??3years in the heavily hunted population. High human-induced mortality combined with non-limiting food resources accounted for the accelerated life history of the hunted population because of earlier reproduction. Synthesis and applications. For wild boar, we show that when a population is facing a high hunting pressure, increasing the mortality in only one age-class (e.g. adults or juveniles) may not allow managers to limit population growth. We suggest that simulations of management strategies based on context-specific demographic models are useful for selecting interventions for population control. This type of approach allows the assessment of population response to exploitation by considering a range of plausible scenarios, improving the chance of selecting appropriate management actions. ?? 2011 The Authors. Journal of Applied Ecology ?? 2011 British Ecological Society.

Servanty, S.; Gaillard, J. -M.; Ronchi, F.; Focardi, S.; Baubet, E.; Gimenez, O.

2011-01-01

323

Demographic Processes Underlying Subtle Patterns of Population Structure in the Scalloped Hammerhead Shark, Sphyrna lewini  

PubMed Central

Genetic diversity (?), effective population size (Ne), and contemporary levels of gene flow are important parameters to estimate for species of conservation concern, such as the globally endangered scalloped hammerhead shark, Sphyrna lewini. Therefore, we have reconstructed the demographic history of S. lewini across its Eastern Pacific (EP) range by applying classical and coalescent population genetic methods to a combination of 15 microsatellite loci and mtDNA control region sequences. In addition to significant population genetic structure and isolation-by-distance among seven coastal sites between central Mexico and Ecuador, the analyses revealed that all populations have experienced a bottleneck and that all current values of ? are at least an order of magnitude smaller than ancestral ?, indicating large decreases in Ne (??=?4Ne?), where ? is the mutation rate. Application of the isolation-with-migration (IM) model showed modest but significant genetic connectivity between most sampled sites (point estimates of Nm?=?0.1–16.7), with divergence times (t) among all populations significantly greater than zero. Using a conservative (i.e., slow) fossil-based taxon-specific phylogenetic calibration for mtDNA mutation rates, posterior probability distributions (PPDs) for the onset of the decline in Ne predate modern fishing in this region. The cause of decline over the last several thousand years is unknown but is highly atypical as a post-glacial demographic history. Regardless of the cause, our data and analyses suggest that S. lewini was far more abundant throughout the EP in the past than at present.

Nance, Holly A.; Klimley, Peter; Galvan-Magana, Felipe; Martinez-Ortiz, Jimmy; Marko, Peter B.

2011-01-01

324

Socio-demographic and clinical characteristics of re-presentation to an Australian inner-city emergency department: implications for service delivery  

Microsoft Academic Search

BACKGROUND: People who have complex health care needs frequently access emergency departments for treatment of acute illness and injury. In particular, evidence suggests that those who are homeless, or suffer mental illness, or have a history of substance misuse, are often repeat users of emergency departments. The aim of this study was to describe the socio-demographic and clinical characteristics of

Gaye Moore; Marie Gerdtz; Elizabeth Manias; Graham Hepworth; Andrew Dent

2007-01-01

325

Joint Injection/Aspiration  

MedlinePLUS

... bursa or tendon sheath to treat bursitis and tendonitis, respectively. What benefit is derived from a joint ... conditions, such as rheumatoid arthritis, psoriatic arthritis, gout, tendonitis, bursitis and, occasionally, osteoarthritis. What usually is injected ...

326

Joint Contingency Contracting.  

National Technical Information Service (NTIS)

The purpose of this Master of Business Administration (MBA) Professional Report is to investigate and analyze the means by which Contingency Contracting Officers (CCO) can effectively operate in a Joint contingency environment and to validate the Defense ...

E. K. Johnson B. H. Paton E. W. Threat L. A. Haptonstall

2005-01-01

327

Joint Aspiration (Arthrocentesis)  

MedlinePLUS

... arthritis, or JRA), systemic lupus erythematosus (SLE), and Lyme disease. Joint aspiration is diagnostic but it also can ... Parents MORE ON THIS TOPIC Evaluate Your Child's Lyme Disease Risk Juvenile Idiopathic Arthritis Living With Lupus Bones, ...

328

Temporomandibular Joint, Open  

MedlinePLUS

... Dental Research Loan Repayment Programs NIH Loan Repayment Programs ... glide along the joint socket of the temporal bone. The condyles slide back to their original position when we close our mouths. To keep ...

329

Acromioclavicular Joint Separations.  

National Technical Information Service (NTIS)

Acromioclavicular (AC) joint separations are common injuries of the shoulder girdle, especially in the young and active population. Typically the mechanism of this injury is a direct force against the lateral aspect of the adducted shoulder, the magnitude...

F. Martetschlaeger P. J. Millett R. J. Warth T. R. Gaskill

2013-01-01

330

Heuristics for Joint Architecting.  

National Technical Information Service (NTIS)

There is no question that Department of Defense and chairman of the Joint Chiefs of Staff directives have increased the development of operational and systems architectures. The DoD Architectural Framework (DoDAF) and its associated governing publications...

A. Piepkorn G. J. Miller J. Kennedy R. Mills T. Wieser

2006-01-01

331

Joint fluid Gram stain  

MedlinePLUS

Gram stain of joint fluid ... result means no bacteria are present on the Gram stain. Note: Normal value ranges may vary slightly ... Abnormal results mean bacteria were seen on the Gram stain. This may be a sign of a ...

332

Campylobacter infection after prosthetic joint surgery.  

PubMed

Few cases of Campylobacter prosthetic joint infection (PJI) have been reported so far. We describe the demographic characteristics, underlying conditions, clinical features, treatment, and outcome of 8 patients with Campylobacter PJI in our hospital. All strains were confirmed at the French National Reference Center for Campylobacter and Helicobacter. Seven patients were infected with C. fetus and 1 with C. jejuni. Most patients were elderly and immunocompromised. Four had bacteremia, one of these with a pacemaker endocarditis. All the patients received at least 3 months of antibiotic treatment and 6 were treated surgically. The outcome was favorable at 2 years of follow-up in all except for 1 patient. Campylobacter PJI cases are rare but likely to become more frequent. C. fetus bacteremia should motivate physicians to look for a secondary localization such as a Campylobacter PJI. PMID:23808718

Prendki, Virginie; Marmor, Simon; Zeller, Valérie; Lhotellier, Luc; Mégraud, Francis; Desplaces, Nicole

2013-09-01

333

Demographics of Giant Planets--Insights from Theory  

NASA Astrophysics Data System (ADS)

The demographics of giant planets arise from a combination of the physical properties and evolution of protoplanetary disks, the planet formation process itself, and the dynamical evolution of planets post-formation. In this talk, I will review each of these contributions to giant planet demographics with an emphasis on how future discoveries can be used to separate and constrain their effects. I will particularly discuss how giant planet demographics will constrain the mechanism by which giant planets form, an old theoretical problem on the cusp of an observational breakthrough.

Murray-Clay, Ruth

2014-06-01

334

Prosthetic Joint Infections  

PubMed Central

Prosthetic joint infections represent a major therapeutic challenge for both healthcare providers and patients. This paper reviews the predisposing factors, pathogenesis, microbiology, diagnosis, treatment and prophylaxis of prosthetic joint infection. The most optimal management strategy should be identified based on a number of considerations including type and duration of infection, antimicrobial susceptibility of the infecting pathogen, condition of infected tissues and bone stock, patient wishes and functional status.

Aslam, Saima; Darouiche, Rabih O.

2012-01-01

335

High pressure ceramic joint  

DOEpatents

Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present joint when used with recuperators increases the use of ceramic components which do not react to highly corrosive gases. Thus, the present joint used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present joint is comprised of a first ceramic member, a second ceramic member, a mechanical locking device having a groove defined in one of the first ceramic member and the second ceramic member. The joint and the mechanical locking device is further comprised of a refractory material disposed in the groove and contacting the first ceramic member and the second ceramic member. The present joint mechanically provides a high strength load bearing joint having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures.

Ward, Michael E. (Poway, CA); Harkins, Bruce D. (San Diego, CA)

1993-01-01

336

High pressure ceramic joint  

DOEpatents

Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present joint when used with recuperators increases the use of ceramic components which do not react to highly corrosive gases. Thus, the present joint used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present joint is comprised of a first ceramic member, a second ceramic member, a mechanical locking device having a groove defined in one of the first ceramic member and the second ceramic member. The joint and the mechanical locking device is further comprised of a refractory material disposed in the groove and contacting the first ceramic member and the second ceramic member. The present joint mechanically provides a high strength load bearing joint having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures. 4 figures.

Ward, M.E.; Harkins, B.D.

1993-11-30

337

Joint Consideration of Distal and Proximal Predictors of Premature Mortality among Serious Juvenile Offenders  

PubMed Central

Purpose Juvenile offenders are at heightened risk of death in adolescence and young adulthood compared to adolescents in the general population. The current study extends previous research by testing the joint contributions of distal (historical and demographic characteristics) and proximal (closer to the time of the death) predictors of mortality. We also tested and whether proximal variables were potential mediators of the effects of distal variables on mortality. Methods Participants were 1,354 serious juvenile offenders, 45 (3.32%) of whom were deceased by the completion of the study. Data were collected through self-reports and official records. Results Significant distal predictors of mortality were being African-American and having a history of substance use disorder. Proximal predictors that added significantly to prediction included gun carrying, gang membership, and substance use problems. Potential mediators of the effects of substance use disorder history were continuing substance use problems and gang membership. However, proximal variables could not explain the heightened risk for African-Americans. Conclusions Gang membership, gun carrying, and substance use problems are risk factors for early mortality among juvenile offenders, but they do not explain the elevated risk for death among African Americans. Thus, further research is needed to understand the mechanisms underlying risk for premature death among African-American adolescent offenders. Implications and contributions Findings suggest that interventions to reduce substance use problems, gang membership, and gun carrying have the potential to reduce risk of mortality for serious juvenile offenders. However, these factors cannot explain the heightened risk for death among African-American participants.

Chassin, Laurie; Piquero, Alex R.; Losoya, Sandra H.; Mansion, Andre D.; Schubert, Carol A.

2012-01-01

338

Assessing patterns of fish demographics and habitat in stream networks  

EPA Science Inventory

Effective habitat restoration planning requires correctly anticipating demographic responses to altered habitats. New applications of Passive Integrated Transponder (PIT) tag technology to fish-habitat research have provided critical insights into fish movement, growth, and surv...

339

Demographic Trends Affecting State Educational Planning: A Florida Example  

ERIC Educational Resources Information Center

This paper reports work that studied past and future demographic trends and their impact on education in Florida, and presents a model for studying variables affecting enrollment. Numerous tables and graphs are included. (Author/IRT)

Chang, Martha J.

1977-01-01

340

Dream Recall and Political Ideology: Results of a Demographic Survey  

Microsoft Academic Search

This report presents findings from a survey of 2992 demographically diverse American adults who answered questions about dream recall and questions about their political views. Participants who described themselves as \\

Kelly Bulkeley

2012-01-01

341

Profile: the Chakaria Health and Demographic Surveillance System.  

PubMed

Chakaria Health and Demographic Surveillance System (CHDSS), located on the south-eastern coast of the Bay of Bengal, was established in 1999 and is one of the field sites of International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDRB). The surveillance covers 118 315 residents living in 19 847 households. Data on socio-demographic and health indicators including birth, death, migration, marriage, maternal health, education and employment are recorded through quarterly household visits. The primary objective of CHDSS is to monitor the changes in socio-demographic indicators, inequalities in health and impact of public health interventions. A demographic change was accompanied by a shift from traditional to modern society during the past decade, but inequality in health still persists. The findings from the surveillance are shared regularly among the local and global communities. Data are also available upon request to ICDDRB and INDEPTH for use by researchers and policy makers. PMID:22798692

Hanifi, Manzoor Ahmed; Mamun, Abdullah Al; Paul, Ashish; Hasan, Sharif Al; Hoque, Shahidul; Sharmin, Sifat; Urni, Farhana; Khan, Imran Reza; Mahmood, Shehrin Shaila; Rasheed, Sabrina; Iqbal, Mohammad; Moula, Ariful; Rahman, Mijanur; Bhuiya, Abbas

2012-06-01

342

Demographics and the social reckoning in the Arab region.  

PubMed

Demographic transitions in the Arab countries, due to declining birth rates and mortality rates since the 1980s, are reflected in a low proportion of children, a relatively stable proportion of elderly and a high proportion of people of working age. This "youth bulge" of young, active, working-age individuals in the current population may open a demographic window for countries to benefit from increased savings and investment. This paper reviews the demographic situation in the Arab region and the impact of education, employment, migration, health status and participation in society on the further development of the region, including the impact of these factors on ageing and gender issues. The intent is to draw attention to the importance of these demographic changes and highlight the need for action to maximize the potential benefit to the population in this region. PMID:23882965

Kronfol, N M

2013-04-01

343

Demographic, agricultural products, and food consumption data for a collective farm in Oranoe District, Ivankov District, Kiev Region, Ukraine  

SciTech Connect

This report provides some demographic, agricultural and food consumption data for the collective farms ( Kybisheva,'' composed of three villages) in the Oranoe Department, District of Ivankov, Kiev Region. This area is situated approximately 15 km south of the Chernobyl 30-km Exclusion Zone. The levels of {sup 137}Cs are approximately 5--10 curies/km{sup 2}. This data was collected by the Integrated Radioecological Expedition to Chernobyl of the Russian Academy of Sciences as part of the co-operative studies on environmental radiation dose assessment conducted under the US/USSR Joint Co-operative Committee on Civilian Nuclear Reactor Safety (JCCCNRS) established in 1989.

Ryabov, I N [AN SSSR, Moscow (Russian Federation). Inst. of Animal Evolutionary, Morphology and Ecology ECOPOLIS, Kiev (Ukraine); Davidenko, G M [ECOPOLIS, Kiev (Ukraine); Templeton, W L [Pacific Northwest Lab, Richland, WA (United States); ,

1992-07-01

344

Habitat and Scale Shape the Demographic Fate of the Keystone Sea Urchin Paracentrotus lividus in Mediterranean Macrophyte Communities  

PubMed Central

Demographic processes exert different degrees of control as individuals grow, and in species that span several habitats and spatial scales, this can influence our ability to predict their population at a particular life-history stage given the previous life stage. In particular, when keystone species are involved, this relative coupling between demographic stages can have significant implications for the functioning of ecosystems. We examined benthic and pelagic abundances of the sea urchin Paracentrotus lividus in order to: 1) understand the main life-history bottlenecks by observing the degree of coupling between demographic stages; and 2) explore the processes driving these linkages. P. lividus is the dominant invertebrate herbivore in the Mediterranean Sea, and has been repeatedly observed to overgraze shallow beds of the seagrass Posidonia oceanica and rocky macroalgal communities. We used a hierarchical sampling design at different spatial scales (100 s, 10 s and <1 km) and habitats (seagrass and rocky macroalgae) to describe the spatial patterns in the abundance of different demographic stages (larvae, settlers, recruits and adults). Our results indicate that large-scale factors (potentially currents, nutrients, temperature, etc.) determine larval availability and settlement in the pelagic stages of urchin life history. In rocky macroalgal habitats, benthic processes (like predation) acting at large or medium scales drive adult abundances. In contrast, adult numbers in seagrass meadows are most likely influenced by factors like local migration (from adjoining rocky habitats) functioning at much smaller scales. The complexity of spatial and habitat-dependent processes shaping urchin populations demands a multiplicity of approaches when addressing habitat conservation actions, yet such actions are currently mostly aimed at managing predation processes and fish numbers. We argue that a more holistic ecosystem management also needs to incorporate the landscape and habitat-quality level processes (eutrophication, fragmentation, etc.) that together regulate the populations of this keystone herbivore.

Prado, Patricia; Tomas, Fiona; Pinna, Stefania; Farina, Simone; Roca, Guillem; Ceccherelli, Giulia; Romero, Javier; Alcoverro, Teresa

2012-01-01

345

[Some unique characteristics of the demographic situation in Russia].  

PubMed

The authors briefly describe the demographic situation in the Russian Soviet Federated Socialist Republic, using data from the 1989 census and current demographic research. Changes in the birth rate and population growth are examined, and migration flows in the various regions of the republic are compared. Factors affecting low birth rates are analyzed, and trends in marriage, divorce, mortality, and life expectancy are explored. PMID:12178735

Brui, B; Mikhailov, E

1991-01-01

346

71 FR 3313 - Proposed Collection; Comment Request; Collection of Demographic and Smoking/Tobacco Use...  

Federal Register 2010, 2011, 2012, 2013

...Demographic and Smoking/Tobacco Use Information From NCI Cancer Information Service...Demographic and Smoking/ Tobacco Use Information from NCI Cancer Information Service...demographic and smoking intake questions...clients who are cancer patients,...

2006-01-20

347

Bilateral, atraumatic, proximal tibiofibular joint instability.  

PubMed

Dislocation of the tibiofibular joint is rare and usually results from a traumatic event. Only 1 case of atraumatic proximal tibiofibular joint instability in a 14-year-old girl has been reported in the literature, however this condition might occur more frequently than once thought. A wide range of treatment options exist for tibiofibular dislocations. Currently, the first choice is a conservative approach, and when this fails, surgical means such as resection of the fibula head, arthrodesis, and reconstruction are considered. However, no consensus exists on the most effective treatment. This article reports a unique case of bilateral, atraumatic, proximal tibia and fibular joint instability involving a 30-year-old man with a 20-year history of pain and laxity in the right knee. The patient had no trauma to his knees; he reported 2 immediate family members with similar complaints, which suggests that this case is likely congenital. After conservative approaches proved to be ineffective, the patient underwent capsular reconstruction using free autologous gracilis tendon. At 6-month postoperative follow-up, the patient was pain free with no locking and instability. He then underwent surgery on the left knee. At 1-year follow-up after the second surgery, the patient had no symptoms or restrictions in mobility. We provide an alternative surgical approach to arthrodesis and resection for the treatment of chronic proximal tibiofibular instability. In the treatment of chronic tibiofibular instability, we believe that reconstruction of the tibiofibular joint is a safe and effective choice. PMID:21323280

Morrison, Troy D; Shaer, James A; Little, Jill E

2011-02-01

348

Dissimilar metals joint evaluation  

NASA Technical Reports Server (NTRS)

Dissimilar metals tubular joints between 2219-T851 aluminum alloy and 304L stainless steel were fabricated and tested to evaluate bonding processes. Joints were fabricated by four processes: (1) inertia (friction) weldings, where the metals are spun and forced together to create the weld; (2) explosive welding, where the metals are impacted together at high velocity; (3) co-extrusion, where the metals are extruded in contact at high temperature to promote diffusion; and (4) swaging, where residual stresses in the metals after a stretching operation maintain forced contact in mutual shear areas. Fifteen joints of each type were prepared and evaluated in a 6.35 cm (2.50 in.) O.D. size, with 0.32 cm (0.13 in.) wall thickness, and 7.6 cm (3.0 in) total length. The joints were tested to evaluate their ability to withstand pressure cycle, thermal cycle, galvanic corrosion and burst tests. Leakage tests and other non-destructive test techniques were used to evaluate the behavior of the joints, and the microstructure of the bond areas was analyzed.

Wakefield, M. E.; Apodaca, L. E.

1974-01-01

349

Periprosthetic Joint Infections  

PubMed Central

Implantation of joint prostheses is becoming increasingly common, especially for the hip and knee. Infection is considered to be the most devastating of prosthesis-related complications, leading to prolonged hospitalization, repeated surgical intervention, and even definitive loss of the implant. The main risk factors to periprosthetic joint infections (PJIs) are advanced age, malnutrition, obesity, diabetes mellitus, HIV infection at an advanced stage, presence of distant infectious foci, and antecedents of arthroscopy or infection in previous arthroplasty. Joint prostheses can become infected through three different routes: direct implantation, hematogenic infection, and reactivation of latent infection. Gram-positive bacteria predominate in cases of PJI, mainly Staphylococcus aureus and Staphylococcus epidermidis. PJIs present characteristic signs that can be divided into acute and chronic manifestations. The main imaging method used in diagnosing joint prosthesis infections is X-ray. Computed tomography (CT) scan may assist in distinguishing between septic and aseptic loosening. Three-phase bone scintigraphy using technetium has high sensitivity, but low specificity. Positron emission tomography using fluorodeoxyglucose (FDG-PET) presents very divergent results in the literature. Definitive diagnosis of infection should be made by isolating the microorganism through cultures on material obtained from joint fluid puncturing, surgical wound secretions, surgical debridement procedures, or sonication fluid. Success in treating PJI depends on extensive surgical debridement and adequate and effective antibiotic therapy. Treatment in two stages using a spacer is recommended for most chronic infections in arthroplasty cases. Treatment in a single procedure is appropriate in carefully selected cases.

Lima, Ana Lucia L.; Oliveira, Priscila R.; Carvalho, Vladimir C.; Saconi, Eduardo S.; Cabrita, Henrique B.; Rodrigues, Marcelo B.

2013-01-01

350

VA Health Care: Additional Efforts to Better Assess Joint Ventures Needed.  

National Technical Information Service (NTIS)

The Department of Veterans Affairs (VA) and the Department of Defense (DOD) have a long history of partnering to achieve more cost-effective use of health care resources. Their partnerships have evolved to include joint ventures--joint efforts to construc...

2008-01-01

351

Robotic Bladder Joint  

NASA Technical Reports Server (NTRS)

Reliable, lightweight robotic joint suitable for variety of applications, actuated hydraulically, without need for heavy mechanical cylinders or gears on joint itself. Includes two members; first member rotates about pin at end of second member. Includes cam, over which tension line stretched. Ends of tension line anchored at end of second member opposite end that holds pin. Bladder placed on each side of second member, squeezed between second member and tension line. Pressures and/or amounts of fluid in bladders controlled by use of conventional equipment like pumps, valves, and reservoirs. Bladder on one side inflated more than on other side; greater inflation on one side causes greater stretching of tension line on that side. Greater tension pulls on cam, turning first member toward that side. Angle of joint controlled by controlling differential inflation of two bladders.

Robertson, Glen A.

1995-01-01

352

Gait biomechanics and the evolution of total joint replacement  

Microsoft Academic Search

The history and evolution of total knee and total hip replacement has been influenced substantially by the knowledge obtained from gait analysis studies. Many of the mechanical problems associated with these devices have been analyzed and evaluated in terms of the mechanics of walking. The magnitude and pattern of the forces at the hip and knee joints derived from gait

Thomas P. Andriacchi; Debra E. Hurwitz

1997-01-01

353

Subgrouping conduct disorder by psychiatric family history.  

PubMed

The family history of psychiatric disorders, and clinical and demographic characteristics of boys with pervasive aggressive conduct disorder (PACD) were compared to those of boys with situational aggressive conduct disorder and controls. Boys with PACD came from lower socioeconomic backgrounds, had an earlier age of onset, and higher rates of hyperactivity and inattention than boys in the other two groups. Their mothers abused drugs more often than those of boys in the other two groups, while their fathers had more frequent antisocial behavior. Alcohol abuse was more prevalent among fathers of both conduct disorder groups, compared to the fathers of controls. PMID:2592472

Hamdan-Allen, G; Stewart, M A; Beeghly, J H

1989-11-01

354

Metacarpophalangeal joint replacement with osseointegrated endoprostheses.  

PubMed

A new type of endoprosthesis for reconstruction of the metacarpophalangeal (MCP) joint has been tested. The novel arthroplasty consists of a joint mechanism with two screw-shaped fixtures for bone anchorage. These fixtures, of commercially pure titanium, are gently screwed into the anchoring bone on each side of the diseased joint, the aim being to achieve osseointegration, i.e. a direct contact between implant and bone without interposed soft tissue layers. The hand was immobilized in a dorsal splint for 8-10 days post-operatively after which a carefully controlled mobilization program was initiated. In principle, the titanium fixtures, the surgical technique and the primary immobilization represent an approach similar to that previously used in various reconstruction procedures of the jaw. This paper describes 5 case histories of reconstructions required because of osteoarthrosis in a single MCP joint. Prior to the operation, all patients suffered from severe problems resulting from their arthrotic joints and they had not been able to work for several months. After surgery they were evaluated by a clinical assessment program and X-rays were taken at various times of follow-up. As well as visual inspection all radiograms were subjected to densitometry by means of a computer-based image-analysis system in order to provide information on the development of bone density in the bone-to implant interface region. From a functional point of view the treatment with osseointegrated prostheses must be regarded as being successful. All patients were able to go back to their original work and their hands had a satisfactory range of movement and grip strength with no signs of impaired function on longer follow-up time. Clinical problems were one re-operation, one case of implant fracture and one case requiring exchange of the joint mechanism. The computer-assisted evaluation of the radiograms revealed the presence of calcified tissue in many sections where the naked eye was not capable of differentiating any bone. In conclusion, it seems possible to establish osseointegration of MCP-endoprostheses in the arthrotic human joint in complicated cases which were regarded as contraindicated for any other joint arthroplasty. PMID:3798034

Hagert, C G; Brånemark, P I; Albrektsson, T; Strid, K G; Irstam, L

1986-01-01

355

Clinical features of symptomatic patellofemoral joint osteoarthritis  

PubMed Central

Introduction Patellofemoral joint osteoarthritis (OA) is common and leads to pain and disability. However, current classification criteria do not distinguish between patellofemoral and tibiofemoral joint OA. The objective of this study was to provide empirical evidence of the clinical features of patellofemoral joint OA (PFJOA) and to explore the potential for making a confident clinical diagnosis in the community setting. Methods This was a population-based cross-sectional study of 745 adults aged ?50 years with knee pain. Information on risk factors and clinical signs and symptoms was gathered by a self-complete questionnaire, and standardised clinical interview and examination. Three radiographic views of the knee were obtained (weight-bearing semi-flexed posteroanterior, supine skyline and lateral) and individuals were classified into four subsets (no radiographic OA, isolated PFJOA, isolated tibiofemoral joint OA, combined patellofemoral/tibiofemoral joint OA) according to two different cut-offs: 'any OA' and 'moderate to severe OA'. A series of binary logistic and multinomial regression functions were performed to compare the clinical features of each subset and their ability in combination to discriminate PFJOA from other subsets. Results Distinctive clinical features of moderate to severe isolated PFJOA included a history of dramatic swelling, valgus deformity, markedly reduced quadriceps strength, and pain on patellofemoral joint compression. Mild isolated PFJOA was barely distinguished from no radiographic OA (AUC 0.71, 95% CI 0.66, 0.76) with only difficulty descending stairs and coarse crepitus marginally informative over age, sex and body mass index. Other cardinal signs of knee OA - the presence of effusion, bony enlargement, reduced flexion range of movement, mediolateral instability and varus deformity - were indicators of tibiofemoral joint OA. Conclusions Early isolated PFJOA is clinically manifest in symptoms and self-reported functional limitation but has fewer clear clinical signs. More advanced disease is indicated by a small number of simple-to-assess signs and the relative absence of classic signs of knee OA, which are predominantly manifestations of tibiofemoral joint OA. Confident diagnosis of even more advanced PFJOA may be limited in the community setting.

2012-01-01

356

A Prospective Approach to Investigating the Natural History of Pre-Clinical Rheumatoid Arthritis (RA) Using First-Degree Relatives of Probands with RA  

PubMed Central

Objective To describe a large, multi-center prospective cohort study of first-degree relatives (FDRs) of probands with rheumatoid arthritis (RA), and outline the utility of such a study in investigating the natural history of RA development. Methods 1058 FDRs, none of whom met the American College of Rheumatology (ACR) criteria for RA, have been enrolled into a prospective study investigating genetic and environmental influences on the development of RA-related autoimmunity. Demographic, epidemiologic, genetic, autoantibody, and physical examination data from the initial study enrollment visit is described for these FDRs, and the relationship is examined between genetic factors, autoantibodies, inflammation, and joint disease. Results Fifty-five percent of FDRs have ?1 copy of the shared epitope (SE); 20% have ?1 copy of PTPN22 polymorphism; ~16% are positive for rheumatoid factor (RF, including isotypes), and/or anti-cyclic citrullinated peptide (anti-CCP) antibody. RF-IgM positivity is associated with ?1 tender joint/s on examination (OR 2.50, 95% CI 1.27 to 4.89, p<0.01), and elevated levels of CRP (OR 5.31, 95% CI 1.45 to 19.52, p = 0.01). Conclusion FDRs without RA demonstrate high prevalence of genetic risk factors and RA-related autoantibodies. Additionally, RF association with tender joints and elevated CRP suggests autoantibodies are a valid intermediate marker of RA-related autoimmunity in this cohort. This prospective FDR cohort will be a valuable resource for evaluating the relationship between genetic, epidemiologic factors and the development of RA-related autoimmunity.

Kolfenbach, Jason R.; Deane, Kevin D.; Derber, Lezlie A.; O'Donnell, Colin; Weisman, Michael H.; Buckner, Jane H.; Gersuk, Vivian H.; Wei, Shan; Mikuls, Ted R.; O'Dell, James; Gregersen, Peter K.; Keating, Richard M.; Norris, Jill M.; Holers, V. Michael

2009-01-01

357

Field Museum of Natural History  

NSDL National Science Digital Library

The Field Museum of Natural History in Chicago was founded to house the biological and anthropological collections assembled for the World's Columbian Exposition of 1893. These objects form the core of the Museum's collections which have grown to more than twenty million specimens. The collections form the foundation of the Museum's exhibition, research and education programs, which are further informed by a world-class natural history library of more than 250,000 volumes. The Museum features a number of earth science exhibits, including the Hall of Gems, Moving Earth about plate Tectonics, a fossil Preparation Laboratory, Evolving Planet a permanent exhibit showcasing 4 billion years of life history, from single celled organisms through human ancestors. The Harris Loan Program provides educational outreach to children, bringing artifacts, specimens, audiovisual materials, and activity kits to area schools, as well as resources for educators, including select Field Museum programs available for listening or download as a part of Chicago Amplified. There are a number of online exhibits, interactives, curricula, and information on conservation projects. Also offered are classes, lectures, field trips, museum overnights and special events for families, adults and children. The Museum's curatorial and scientific staff has been an international leader in evolutionary biology and paleontology, and archaeology and ethnography, and has long maintained close links - including joint teaching, students, seminars - with local universities.

358

Hominin life history: reconstruction and evolution  

PubMed Central

In this review we attempt to reconstruct the evolutionary history of hominin life history from extant and fossil evidence. We utilize demographic life history theory and distinguish life history variables, traits such as weaning, age at sexual maturity, and life span, from life history-related variables such as body mass, brain growth, and dental development. The latter are either linked with, or can be used to make inferences about, life history, thus providing an opportunity for estimating life history parameters in fossil taxa. We compare the life history variables of modern great apes and identify traits that are likely to be shared by the last common ancestor of Pan-Homo and those likely to be derived in hominins. All great apes exhibit slow life histories and we infer this to be true of the last common ancestor of Pan-Homo and the stem hominin. Modern human life histories are even slower, exhibiting distinctively long post-menopausal life spans and later ages at maturity, pointing to a reduction in adult mortality since the Pan-Homo split. We suggest that lower adult mortality, distinctively short interbirth intervals, and early weaning characteristic of modern humans are derived features resulting from cooperative breeding. We evaluate the fidelity of three life history-related variables, body mass, brain growth and dental development, with the life history parameters of living great apes. We found that body mass is the best predictor of great ape life history events. Brain growth trajectories and dental development and eruption are weakly related proxies and inferences from them should be made with caution. We evaluate the evidence of life history-related variables available for extinct species and find that prior to the transitional hominins there is no evidence of any hominin taxon possessing a body size, brain size or aspects of dental development much different from what we assume to be the primitive life history pattern for the Pan-Homo clade. Data for life history-related variables among the transitional hominin grade are consistent and none agrees with a modern human pattern. Aside from mean body mass, adult brain size, crown and root formation times, and the timing and sequence of dental eruption of Homo erectus are inconsistent with that of modern humans. Homo antecessor fossil material suggests a brain size similar to that of Homo erectus s. s., and crown formation times that are not yet modern, though there is some evidence of modern human-like timing of tooth formation and eruption. The body sizes, brain sizes, and dental development of Homo heidelbergensis and Homo neanderthalensis are consistent with a modern human life history but samples are too small to be certain that they have life histories within the modern human range. As more life history-related variable information for hominin species accumulates we are discovering that they can also have distinctive life histories that do not conform to any living model. At least one extinct hominin subclade, Paranthropus, has a pattern of dental life history-related variables that most likely set it apart from the life histories of both modern humans and chimpanzees.

Robson, Shannen L; Wood, Bernard

2008-01-01

359

New Joint Sealants. Criteria, Design and Materials.  

ERIC Educational Resources Information Center

Contents include--(1) sealing concrete joints, (2) sealing glass and metal joints, (3) metal and glass joint sealants from a fabricator's viewpoint, (4) a theory of adhesion for joint sealants, (5) geometry of simple joint seals under strain, (6) joint sealant specifications from a manufacturer's viewpoint, (7) joint sealant requirements from an…

Building Research Inst., Inc., Washington, DC.

360

Joint Fires Training Guide for a Corps Joint Task Force.  

National Technical Information Service (NTIS)

A detailed analysis of responsibilities, inputs, processes, outputs, and interactions was conducted for the staff elements and cells involved in joint fires at the Corps Joint Task Force level. This research product documents that analysis. The purpose of...

J. F. Love

1998-01-01

361

Principles of Jointness.  

National Technical Information Service (NTIS)

Despite all the attention given to jointness since World War II, there is no comprehensive theory that underpins the concept in doctrine. This is unusual in light of the large body of literature on operational art. Most military practitioners find operati...

R. C. Rubel

2001-01-01

362

Periprosthetic Joint Infection  

Microsoft Academic Search

The orthopedic community has begun to witness a worrisome rise in the incidence of periprosthetic joint infections (PJIs) caused by resistant organisms. Besides other challenges associated with treating these infections, it appears that these infections may pose a higher cost compared to infections caused by sensitive organisms. Significantly higher cost of care for treatment of infections due to methicillin-resistant organisms

Javad Parvizi; Ian M. Pawasarat; Khalid A. Azzam; Ashish Joshi; Erik N. Hansen; Kevin J. Bozic

2010-01-01

363

eHistory at OSU: Multimedia Histories  

NSDL National Science Digital Library

Drawing on the power and abilities of the Internet, the eHistory website from Ohio State University offers multimedia portraits on topics that include immigration in the United States and the Louisiana Purchase. On the homepage, visitors can take a look at the "What is a 'Multimedia History'?" area to learn more about these features, and then move on over to the "Featured Multimedia History". The histories include interactive maps and images, along with narrative essays. Visitors can scan over the complete histories and also view one of their three video presentations. If they are interested, visitors can also sign up to receive Twitter updates or their RSS feed. Additionally, the site also contains links to the other areas of the eHistory site, such as their online books, timelines, and primary sources.

364

Microforms and Sport History.  

ERIC Educational Resources Information Center

Explores the importance of sport history as it reflects the social and cultural history of the United States. Discussion covers the various sport history materials that are available in microform, including the Spalding Collection, twentieth-century microfilm sources, and sports and social history (Sports Periodicals microfilm series). (EJS)

Levine, Peter

1986-01-01

365

Let History Reign  

ERIC Educational Resources Information Center

Spanish River High School is one of 40 U.S. History Schools and 21 affiliates around the country that get resources and academic support from the Gilder Lehrman Institute of American History. The schools require participating students to take a U.S. history course each year, in addition to any requisites in world history and other subjects. The…

Manzo, Kathleen Kennedy

2008-01-01

366

Teaching History Today.  

ERIC Educational Resources Information Center

The 14 articles included in this collection touch on several aspects of the teaching of history. The articles are: (1) "Observations on University Teaching and Research" (N. Graebner); (2) "Teaching History: A Changing Clientele and an Affirmation of Goals" (E. Burns); (3) "History for Citizens" (W. McNeill); (4) "Reflections on the History of…

Bausum, Henry S., Ed.

367

Endogenous technological and demographic change under increasing water scarcity  

NASA Astrophysics Data System (ADS)

Many ancient civilizations such as the Indus Valley civilization dispersed under extreme dry conditions. Even contemporary societies such as the one in Murrumbidgee river basin, Australia, have started to witness a decline in overall population under increasing water scarcity. Skeptics of hydroclimatic determinism have often cautioned against the use of hydroclimatic change as the sole predictor of the fate of contemporary societies in water scarce regions by suggesting that technological change may ameliorate the effects of increasing water scarcity. We here develop a simple overlapping generations model of endogenous technological and demographic change. It models technological change not as an exogenous random sequence of events but as an endogenous process (as is widely accepted in contemporary literature) that depends on factors such as the investments that are (endogenously) made in a society, the endogenous diversification of a society into skilled and unskilled workers, individuals' patience in terms of its present consumption versus future consumption, the production technology and the (endogenous) interaction of these factors. The population growth rate is modeled to decline once consumption per capita crosses a ';survival' threshold. The model demonstrates that technological change may ameliorate the effects of increasing water scarcity but only to a certain extent in many cases. It is possible that technological change may allow a society to escape the effect of increasing water society, leading to an exponential rise in technology and population. However, such cases require that the rate of success of investment in technological advancement is high. In other more realistic cases of technological success, we find that endogenous technology change has an effect delaying the peak of population before it starts to decline. While the model is a rather simple model of societal growth, it is capable of replicating (not to scale) patterns of technological change (proxies of which in ancient technology include irrigation canals, metal tools, and the use of horses for labor while in contemporary societies its proxies may be the advent of drip irrigation, increasing reservoir storage capacity etc) and population change. It is capable of replicating the pattern of declining consumption per capita in presence of growth in aggregate production. It is also capable of modeling the exponential population rise even under increasing water scarcity. The results of the model suggest, as one of the many other possible explanations, that ancient societies that declined in the face of extreme water scarcity may have done so due to slower rate of success of investment in technological advancement. The model suggests that the population decline occurs after a prolonged decline in consumption per capita, which in turn is due to the joint effect of initially increasing population and increasing water scarcity. This is despite technological advancement and increase in aggregate production. Thus declining consumption per capita despite technological advancement and increase in aggregate production may serve as a useful predictor of upcoming decline in contemporary societies in water scarce basins.

Pande, S.; Ertsen, M.; Sivapalan, M.

2013-12-01

368

Endogenous technological and demographic change under increasing water scarcity  

NASA Astrophysics Data System (ADS)

The ancient civilization in the Indus Valley civilization dispersed under extreme dry conditions; there are indications that the same holds for many other ancient societies. Even contemporary societies, such as the one in Murrumbidgee river basin in Australia, have started to witness a decline in overall population under increasing water scarcity. Hydroclimatic change may not be the sole predictor of the fate of contemporary societies in water scarce regions and many critics of such (perceived) hydroclimatic determinism have suggested that technological change may ameliorate the effects of increasing water scarcity and as such counter the effects of hydroclimatic changes. To study the role of technological change on the dynamics of coupled human-water systems, we develop a simple overlapping-generations model of endogenous technological and demographic change. We model technological change as an endogenous process that depends on factors such as the investments that are (endogenously) made in a society, the (endogenous) diversification of a society into skilled and unskilled workers, a society's patience in terms of its present consumption vs. future consumption, production technology and the (endogenous) interaction of all of these factors. In the model the population growth rate is programmed to decline once consumption per capita crosses a "survival" threshold. This means we do not treat technology as an exogenous random sequence of events, but instead assume that it results (endogenously) from societal actions. The model demonstrates that technological change may indeed ameliorate the effects of increasing water scarcity but typically it does so only to a certain extent. It is possible that technological change may allow a society to escape the effect of increasing water scarcity, leading to a (super)-exponential rise in technology and population. However, such cases require the rate of success of investment in technological advancement to be high. In other more realistic cases of technological success, we find that endogenous technology change only helps to delay the peak of population size before it inevitably starts to decline. While the model is a rather simple model of societal development, it is shown to be capable of replicating patterns of technological and population changes. It is capable of replicating the pattern of declining consumption per capita in presence of growth in aggregate production. It is also capable of replicating an exponential population rise, even under increasing water scarcity. The results of the model suggest that societies that declined or are declining in the face of extreme water scarcity may have done so due to slower rate of success of investment in technological advancement. The model suggests that the population decline occurs after a prolonged decline in consumption per capita, which in turn is due to the joint effect of initially increasing population and increasing water scarcity. This is despite technological advancement and increase in aggregate production. We suggest that declining consumption per capita despite technological advancement and increase in aggregate production may serve as a useful predictor of upcoming decline in contemporary societies in water scarce basins.

Pande, Saket; Ertsen, Maurits; Sivapalan, Murugesu

2014-05-01

369

Joints in a Cornstarch Analog  

NSDL National Science Digital Library

Joints are very important to problems in applied geology (fluid flow, slope stability), but three-dimensional exposures of simple joint sets are not readily accessible from my campus. I developed this exercise based on the experiments of Miller (2001) to give students hands-on practice describing and interpreting joints. For the exercise, I prepare a cornstarch-water mixture a few days in advance and pour it into plastic petri dishes. I add a "flaw" to each dish (typically a small pebble). As the cornstarch dries, vertical joints develop. In class, each group of 3-4 students is provided a petri dish of desiccated cornstarch. Students are asked to draw a map of the joints, paying particular attention to intersection angles. (The joints curve to intersect at 90 degrees.) They determine relative ages of the joints using abutting relationships. (Typically 3-6 generations of joints.) Students next dissect the sample and describe the surface textures of the larger joints and the location of the flaw. The cornstarch produces beautiful plumose structure (hackles). Students then interpret the joint propagation direction from the surface textures, and note the origin of the joint. (Typically, a first- or second-generation joint initiates at the flaw.) Students discuss the role of flaws in the initiation of joints in their groups.

Crider, Juliet

370

Demographic factors and land-use planning in the small islands of Southern Europe  

NASA Astrophysics Data System (ADS)

Since the end of the 1970s, the southern European countries have shown an exceptional reduction in fertility rate. From the highest levels among the developed nations, these countries dropped beneath the substitution rate level: in Greece there is an average of about 1.5 children per woman, and Italy (starting three to four years ago), with 1.3 children per woman, is now the country with the lowest fecundity rate in the world. Land-use planning in southern European small islands therefore requires substantial revision. In the areas where western civilization began, which are highly populated and have a long history, cultural and ethnic aspects of tradition are fundamental to environmental management and to the defense of historical heritage. They also place a strong value on sustaining tourism, the most relevant economic activity, that allows them to survive and maintain a high welfare level. For some decades they have had populations with a marked presence of young people and high emigration rates, but now they are fast becoming dominated by the elderly and must prepare for a period of fast reduction in youth of the workforce, while the peripheral areas of Asia and Africa are entering a sudden demographic growth phase. The demographic structure has also been deeply altered both by previous migrations and by random variations, as usually happens in all small communities. Social services for younger and older people have had to be adapted rapidly, reorganizing high-school management, hospital and health-care structures, in-house assistance, and so on. There is a need to rethink the job market and favor the immigration of highly specialized workers, which is a necessity for technical evolution. Sustainable development is constrained nowadays not only by the scarcity of natural resources, but also by the quality and quantity of human resources. Proper policies for population and land-use planning are highly correlated factors; they have to be considered with respect of these new, rapid demographic changes.

Soliani, Lamberto; Rossi, Orazio

1992-09-01

371

Comparison of 2 temporomandibular joint total joint prosthesis systems  

Microsoft Academic Search

Purpose: The study goal was to evaluate the comparative outcomes of patients treated with temporomandibular joint (TMJ) total joint prostheses, using either the Christensen prosthesis (TMJ Inc, Golden, CO) (CP) or the TMJ Concepts prosthesis (TMJ Concepts Inc, Camarillo, CA; formerly Techmedica Inc) (TP). Patients and Methods: Forty-five consecutive patients treated with either CP or TP total joint prostheses were

Larry M. Wolford; Douglas J. Dingwerth; Reena M. Talwar; Marcos C. Pitta

2003-01-01

372

Radiograph utilization and demographics in a chiropractic college teaching clinic  

PubMed Central

Objective The purpose of this study is to present radiograph utilization at a chiropractic college teaching clinic, the associated patient demographics, and the utilization rates by body region. Methods Data for outpatient services over a 3-year period were extracted from a college clinic administrative software program. Radiographic data were matched with patient demographic information providing the age, sex, and financial class for all patients. Results The overall radiograph utilization rate was 8%, with the highest frequency occurring in the spine in the order of lumbar, cervical, and then thoracic regions. Spinal radiographs made up 66% of the total radiographs taken. The utilization rate increased as the age of the patients increased. The average patient age was 46, and 48% were female. Conclusion The radiograph utilization rate at this teaching clinic was lower than previous studies. This study provides new information regarding overall and regional radiography rates and associated patient demographics from an American chiropractic college.

Lew, Makani; Snow, Gregory J.

2012-01-01

373

Evaluation of the Hip: History and Physical Examination  

PubMed Central

Examination of a painful hip is fairly concise and reliable at detecting the presence of a hip joint problem. Hip joint disorders often go undetected, leading to the development of secondary disorders. Using a thoughtful approach and methodical examination techniques, most hip joint problems can be detected and a proper treatment strategy can then be implemented based on an accurate diagnosis. The purpose of this clinical commentary is to present a systematic examination process that outlines important components in each of the evaluation areas of history and physical examination (including inspection, measurements, symptom localization, muscle strength, and special tests).

2007-01-01

374

What is Joint Interdependence Anyway.  

National Technical Information Service (NTIS)

There is much ado lately about the concept of 'joint interdependence' in future military operations. More than one four-star general has praised Operation Desert Storm's joint deconfliction; that is, the conduct of relatively independent service operation...

C. R. Paparone J. A. Crupi

2004-01-01

375

Socio-demographic distribution of vestibular schwannomas in Denmark.  

PubMed

Abstract Conclusion: Vestibular schwannomas (VSs) are diagnosed less frequently in the remote parts of Denmark, whereas the diagnostic age and tumor size is the same across the different socio-demographic areas of Denmark. Objective: To determine whether VSs are diagnosed equally often in different socio-demographic areas of Denmark and whether a change has occurred during the period 1976-2012. In addition, differences in diagnostic age and tumor size between areas were explored. Methods: Since 1976, all patients diagnosed with a VS in Denmark have been registered in a national database, in which information on, for example, the size of the tumor and the age and address of the patient has been registered. Up to 2012, 2739 patients were diagnosed with a VS. Patient distribution according to area of habitat was determined by subgrouping into urban, suburban, rural, and remote municipalities, using the definitions of socio-demographic areas elaborated by Demarks Statistic. Results: The mean national incidence increased almost linearly over the time period from 6.1 per million per year in the first period from 1976 to 1984, to 22.1 per million per year in the last period from 2003 to 2012. There was a lower incidence at the end of the period in the remote areas compared with the other socio-demographic areas (1976-1984, p = 0.05 and 2003-2011, p = 0.001). The mean age at diagnosis increased during the period, from 52.6 years in the first period to 58.6 years in the last period. There was no significant difference in the age distribution between socio- demographic areas. The mean diagnostic tumor size decreased during the period, from 28.6 mm in the first period to about 10 mm in the last period. There was no significant difference in the size of the tumor between socio- demographic areas. PMID:24655069

Stepanidis, Karen; Kessel, Marie; Caye-Thomasen, Per; Stangerup, Sven-Eric

2014-06-01

376

Demographic fitness of Belminus ferroae (Hemiptera: Triatominae) on three different hosts under laboratory conditions  

PubMed Central

Triatominae are widely recognised for their role as vectors of Trypanosoma cruzi. One of the main biological characteristics of this subfamily is their obligate haematophagous condition. However, previous studies on Belminus herreri and Belminus ferroae suggested that cockroaches are their principal hosts in domiciles. Due to this peculiar behaviour, the aim of this study was to analyse several demographic and reproductive parameters of B. ferroae fed on three different hosts (mice, cockroaches and Rhodnius prolixus) and relate B. ferroae fitness to these alternative hosts. The cohorts were reared under constant conditions. The egg hatching rate was similar for cohorts fed on cockroaches (69.4%) and R. prolixus (63.8%), but was much lower for the cohort fed on mice (16%). The development time from the nymph to adult stage and the average age of first reproduction (?) presented lower values in the cohort fed on cockroaches, which is consistent with the higher population growth rate associated with this host. Demographic parameters [intrinsic rate of natural increase, finite rate of population growth, net reproductive rate and damping ratio] showed statistically significant differences between the cohorts. Analysis of the life history of B. ferroae revealed a higher fitness related to the cockroach. The implications of these results for the origin of the subfamily are discussed.

Sandoval, Claudia Magaly; Medone, Paula; Nieves, Elsa Evelia; Jaimes, Diego Alexander; Ortiz, Nelcy; Rabinovich, Jorge Eduardo

2013-01-01

377

Incorporating diverse data and realistic complexity into demographic estimation procedures for sea otters  

USGS Publications Warehouse

Reliable information on historical and current population dynamics is central to understanding patterns of growth and decline in animal populations. We developed a maximum likelihood-based analysis to estimate spatial and temporal trends in age/sex-specific survival rates for the threatened southern sea otter (Enhydra lutris nereis), using annual population censuses and the age structure of salvaged carcass collections. We evaluated a wide range of possible spatial and temporal effects and used model averaging to incorporate model uncertainty into the resulting estimates of key vital rates and their variances. We compared these results to current demographic parameters estimated in a telemetry-based study conducted between 2001 and 2004. These results show that survival has decreased substantially from the early 1990s to the present and is generally lowest in the north-central portion of the population's range. The greatest temporal decrease in survival was for adult females, and variation in the survival of this age/sex class is primarily responsible for regulating population growth and driving population trends. Our results can be used to focus future research on southern sea otters by highlighting the life history stages and mortality factors most relevant to conservation. More broadly, we have illustrated how the powerful and relatively straightforward tools of information-theoretic-based model fitting can be used to sort through and parameterize quite complex demographic modeling frameworks. ?? 2006 by the Ecological Society of America.

Tinker, M. T.; Doak, D. F.; Estes, J. A.; Hatfield, B. B.; Staedler, M. M.; Bodkin, J. L.

2006-01-01

378

Predictive validity of demographically adjusted normative standards for the HIV Dementia Scale  

Microsoft Academic Search

The aim of the current study was to develop and validate demographically adjusted normative standards for the HIV Dementia Scale (HDS). Given the association between demographic variables and the HDS summary score, demographically adjusted normative standards may enhance the classification accuracy of the HDS. Demographically adjusted normative standards were derived from a sample of 182 seronegative healthy participants and were

Erin E. Morgan; Steven Paul Woods; J. Cobb Scott; Meredith Childers; Jennifer Marquie Beck; Ronald J. Ellis; Igor Grant; Robert K. Heaton

2008-01-01

379

Functional traits explain variation in plant life history strategies.  

PubMed

Ecologists seek general explanations for the dramatic variation in species abundances in space and time. An increasingly popular solution is to predict species distributions, dynamics, and responses to environmental change based on easily measured anatomical and morphological traits. Trait-based approaches assume that simple functional traits influence fitness and life history evolution, but rigorous tests of this assumption are lacking, because they require quantitative information about the full lifecycles of many species representing different life histories. Here, we link a global traits database with empirical matrix population models for 222 species and report strong relationships between functional traits and plant life histories. Species with large seeds, long-lived leaves, or dense wood have slow life histories, with mean fitness (i.e., population growth rates) more strongly influenced by survival than by growth or fecundity, compared with fast life history species with small seeds, short-lived leaves, or soft wood. In contrast to measures of demographic contributions to fitness based on whole lifecycles, analyses focused on raw demographic rates may underestimate the strength of association between traits and mean fitness. Our results help establish the physiological basis for plant life history evolution and show the potential for trait-based approaches in population dynamics. PMID:24379395

Adler, Peter B; Salguero-Gómez, Roberto; Compagnoni, Aldo; Hsu, Joanna S; Ray-Mukherjee, Jayanti; Mbeau-Ache, Cyril; Franco, Miguel

2014-01-14

380

Cellular Pressure-Actuated Joint  

NASA Technical Reports Server (NTRS)

A modification of a pressure-actuated joint has been proposed to improve its pressure actuation in such a manner as to reduce the potential for leakage of the pressurizing fluid. The specific joint for which the modification is proposed is a field joint in a reusable solid-fuel rocket motor (RSRM), in which the pressurizing fluid is a mixture of hot combustion gases. The proposed modification could also be applicable to other pressure-actuated joints of similar configuration.

McGuire, John R.

2003-01-01

381

Lumbar spine radiographic features and demographic, clinical, and radiographic knee, hip and hand osteoarthritis: The Johnston County Osteoarthritis Project  

PubMed Central

Objective 1) To determine the prevalence of lumbar spine individual radiographic features (IRF) of disc space narrowing (DSN), osteophytes (OST) and facet joint osteoarthritis (FOA). 2) To describe the frequencies of demographic, clinic and radiographic knee, hip and hand osteoarthritis (OA) across lumbar spine IRF. 3) To determine factors associated with lumbar spine IRF. Methods A cross-sectional study of 840 participants enrolled in the Johnston County OA Project (2003-4). Sample-based prevalence estimates were generated for each lumbar spine IRF. Associations between lumbar spine IRF and demographic, clinical and peripheral joint OA were determined with logistic regression models. Results Sample-based prevalence estimates were similar for DSN (57.6%) and FOA (57.9%) but higher for OST (88.1%) with significant differences across race and gender. Hand and knee OA frequencies increased across IRF whereas the effect was absent for hip OA. African Americans had lower odds of FOA (adjusted odds ratio [aOR]=0.45 (95% CI 0.32, 0.62)) while there was no racial association with DSN and OST. Low back symptoms were associated with DSN (aOR=1.37 (95% CI 1.04, 1.80)) but not OST or FOA. Knee OA was associated with OST (aOR=1.62 (95% CI 1.16, 2.27)) and FOA (aOR=1.69 (95% CI 1.15, 2.49)) but not DSN. Hand OA was associated with FOA (aOR=1.67 (95% CI 1.20, 2.28)) but not with DSN or OST. No associations were found with hip OA. Conclusion These findings underscore the importance of analyzing lumbar spine IRF separately as the associations with demographic, clinic and radiographic knee, hip and hand OA differ widely.

Goode, Adam P.; Marshall, Stephen W.; Renner, Jordan B.; Carey, Timothy S.; Kraus, Virginia B.; Irwin, Debra E.; Sturmer, Til; Jordan, Joanne M.

2012-01-01

382

Plague mortality and demographic depression in later medieval England.  

PubMed

Both direct and indirect evidence implies that England experienced a lengthy period of stagnant or declining population during the later fourteenth and fifteenth centuries. The Black Death of 1348-1349 had brought about profound changes in England's agrarian economy, and this subsequent demographic depression is most commonly interpreted by historians as the result of plague mortality, recurring in severe outbreaks after the disease's introduction into the country. This paper reviews the evidence and assumptions behind this interpretation, in light of recent research by historical demographers and epidemiologists into bubonic plague epidemics and general mortality crises during the post-medieval period. PMID:7027638

Poos, L R

1981-01-01

383

Plague mortality and demographic depression in later medieval England.  

PubMed Central

Both direct and indirect evidence implies that England experienced a lengthy period of stagnant or declining population during the later fourteenth and fifteenth centuries. The Black Death of 1348-1349 had brought about profound changes in England's agrarian economy, and this subsequent demographic depression is most commonly interpreted by historians as the result of plague mortality, recurring in severe outbreaks after the disease's introduction into the country. This paper reviews the evidence and assumptions behind this interpretation, in light of recent research by historical demographers and epidemiologists into bubonic plague epidemics and general mortality crises during the post-medieval period.

Poos, L. R.

1981-01-01

384

Evaluating the demographic buffering hypothesis with vital rates estimated for Weddell seals from 30years of mark-recapture data  

USGS Publications Warehouse

1.Life-history theory predicts that those vital rates that make larger contributions to population growth rate ought to be more strongly buffered against environmental variability than are those that are less important. Despite the importance of the theory for predicting demographic responses to changes in the environment, it is not yet known how pervasive demographic buffering is in animal populations because the validity of most existing studies has been called into question because of methodological deficiencies. 2.We tested for demographic buffering in the southern-most breeding mammal population in the world using data collected from 5558 known-age female Weddell seals over 30years. We first estimated all vital rates simultaneously with mark-recapture analysis and then estimated process variance and covariance in those rates using a hierarchical Bayesian approach. We next calculated the population growth rate's sensitivity to changes in each of the vital rates and tested for evidence of demographic buffering by comparing properly scaled values of sensitivity and process variance in vital rates. 3.We found evidence of positive process covariance between vital rates, which indicates that all vital rates are affected in the same direction by changes in annual environment. Despite the positive correlations, we found strong evidence that demographic buffering occurred through reductions in variation in the vital rates to which population growth rate was most sensitive. Process variation in vital rates was inversely related to sensitivity measures such that variation was greatest in breeding probabilities, intermediate for survival rates of young animals and lowest for survival rates of older animals. 4.Our work contributes to a small but growing set of studies that have used rigorous methods on long-term, detailed data to investigate demographic responses to environmental variation. The information from these studies improves our understanding of life-history evolution in stochastic environments and provides useful information for predicting population responses to future environmental change. Our results for an Antarctic apex predator also provide useful baselines from a marine ecosystem when its top- and middle-trophic levels were not substantially impacted by human activity. ?? 2011 The Authors. Journal of Animal Ecology ?? 2011 British Ecological Society.

Rotella, J. J.; Link, W. A.; Chambert, T.; Stauffer, G. E.; Garrott, R. A.

2012-01-01

385

Clinical and socio-demographic characteristics of university students referred to an eating disorders service.  

PubMed

This study describes the socio-demographic characteristics and eating disorders symptomatology of university students assessed by a specialised NHS eating disorders service in the UK over a 4-year period. Information was gathered on past treatment history, source of referral, details of university and course of study, whether the patient was still open to the service or discharged, and if the patient had dropped out of contact from services. The study also describes the diagnosis of the assessed patients as well as the results of the Eating Disorders Inventory (EDI), Rosenberg Self-Esteem Scale (RSES) and Revised Symptom Check List 90 (SCL-90-R) questionnaires. The study shows that the university students attending an eating disorder service often suffer from severe conditions, which are generally well-established before they start their university studies. The study discusses the implication of those results in service delivery and future service development. PMID:17676683

Arcelus, Jon; Button, Eric

2007-03-01

386

Double slotted socket spherical joint  

DOEpatents

A new class of spherical joints is disclosed. These spherical joints are capable of extremely large angular displacements (full cone angles in excess of 270.degree.), while exhibiting no singularities or dead spots in their range of motion. These joints can improve or simplify a wide range of mechanical devices.

Bieg, Lothar F. (Albuquerque, NM); Benavides, Gilbert L. (Albuquerque, NM)

2001-05-22

387

The Challenges of Joint Attention  

Microsoft Academic Search

This paper discusses the concept of joint at- tention and the dierent skills underlying its development. We argue that joint attention is much more than gaze following or simul- taneous looking because it implies a shared intentional relation to the world. The current state-of-the-art in robotic and computational models of the dierent prerequisites of joint attention is discussed in relation

Frederic Kaplan; Verena V. Hafner

2004-01-01

388

Glued joints in hardwood timber  

Microsoft Academic Search

The use of glued joints offers an option with ample aesthetic and functional possibilities in the design of wood structures. This type of joint is used since years 1970 in countries of North and Central Europe, for the design and construction of glulam (glued laminated timber) structures. This has led to diverse investigations in the experimental analysis of joints made

D Otero Chans; J. Estévez Cimadevila; E. Martín Gutiérrez

2008-01-01

389

Phase 1 Program Joint Report  

NASA Technical Reports Server (NTRS)

This report consists of inputs from each of the Phase I Program Joint Working Groups. The Working Groups were tasked to describe the organizational structure and work processes that they used during the program, joint accomplishments, lessons learned, and applications to the International Space Station Program. This report is a top-level joint reference document that contains information of interest to both countries.

Nield, George C. (Editor); Vorobiev, Pavel Mikhailovich (Editor)

1999-01-01

390

Shoulder joint tuberculosis  

PubMed Central

Summary Background: Despite the fact that joint tuberculosis is one of the most common forms of extrapulmonary tuberculosis, it is a disease entity that is very rare in Poland (less than 100 cases a year in the last 10 years). The symptoms are non-specific, and thus the disease is rarely taken into account in preliminary differential diagnosis. Case Report: A 68-year-old female patient was admitted to the Internal Diseases Clinic due to oedema and pain of the right shoulder joint. The pain has been increasing for about 8 months. Physical examination revealed increased circumference and elevated temperature of the right shoulder joint. Limb function was retained. The full range of radiological and laboratory diagnostic examinations was performed, including the biopsy of the affected tissue which revealed the presence of Mycobacterium tuberculosis in the bacterial culture. Clinical improvement was obtained after introduction of TB drugs. Conclusions: Radiological diagnostic methods (X-ray, CT scans, MRI scans) provide high precision monitoring of articular lesions. However, the decisive diagnosis requires additional laboratory tests as well as histopathological and bacteriological assays.

Ostrowska, Monika; Gietka, Jan; Nesteruk, Tomasz; Piliszek, Agnieszka; Walecki, Jerzy

2012-01-01

391

Ruscoe 983 Joint Sealant: Product Evaluation.  

National Technical Information Service (NTIS)

This report contains a product evaluation of Ruscoe's 983 joint sealant. Ruscoe 983 is an asphalt base single compound joint sealant. It contains an aluminum fortified adhesive and is designed for use on highway expansion joints, bridge joints, and random...

S. L. Tritsch T. M. Wolfe

1986-01-01

392

38 CFR 4.45 - The joints.  

Code of Federal Regulations, 2012 CFR

...The joints. As regards the joints the factors of disability...movement than normal (from flail joint, resections, nonunion of...movements smoothly. (f) Pain on movement, swelling...and ankle are considered major joints; multiple involvements of...

2012-07-01

393

38 CFR 4.45 - The joints.  

Code of Federal Regulations, 2010 CFR

...The joints. As regards the joints the factors of disability...movement than normal (from flail joint, resections, nonunion of...movements smoothly. (f) Pain on movement, swelling...and ankle are considered major joints; multiple involvements of...

2010-07-01

394

38 CFR 4.45 - The joints.  

Code of Federal Regulations, 2011 CFR

...The joints. As regards the joints the factors of disability...movement than normal (from flail joint, resections, nonunion of...movements smoothly. (f) Pain on movement, swelling...and ankle are considered major joints; multiple involvements of...

2011-07-01

395

49 CFR 213.121 - Rail joints.  

Code of Federal Regulations, 2013 CFR

...Transportation 4 2013-10-01 2013-10-01 false Rail joints. 213.121 Section 213.121 Transportation...SAFETY STANDARDS Track Structure § 213.121 Rail joints. (a) Each rail joint, insulated joint, and compromise...

2013-10-01

396

Sexual assault history and risks for sexually transmitted infections among women in an African township in Cape Town, South Africa  

Microsoft Academic Search

Sexual violence is associated with women's risks for HIV infection. The current study investigated factors related to risks for sexually transmitted infections (STIs), including HIV, among South African women with a history of sexual assault. An anonymous street intercept survey of women (N=272) living in an African township in the Western Cape, South Africa assessed demographic characteristics, history of sexual

S. C. Kalichman; L. C. Simbayi

2004-01-01

397

Testing of explosive welding and welded joints: joint mechanism and properties of explosive welded joints  

Microsoft Academic Search

In this study physical mechanism of explosive welding joint was analysed. The mechanism refers to wavy joint with interpass\\u000a and without one. Plastic strain, viscosity and acoustic waves were applied to explain the problem. The own model of the mechanism\\u000a of oxide removal for the direct joint and test results confirming the bonding mechanism were showed.

Bogumil Wronka

2010-01-01

398

Demographic & related differences in ethical views among small businesses  

Microsoft Academic Search

This study examines the effects of demographic characteristics on ethical perceptions. While earlier research has produced conflicting results regarding the predictive power of these variables, significant and definite insights were obtained with proper controls. The following predictors of ethical attitudes are examined: age, gender, marital status, education, dependent children status, region of the country and years in business, while controlling

Paul J. Serwinek

1992-01-01

399

Capital Budgeting vs. Market Timing: An Evaluation Using Demographics  

Microsoft Academic Search

An ongoing debate sets capital budgeting against market timing. The primary difficulty in evaluating these theories is finding distinct exogenous proxies for investment opportunities and mispricing. We use demand shifts induced by demographics to address this problem, and hence, provide a more definitive analysis of the theories. According to capital budgeting, industries anticipating positive demand shifts in the near future

Stefano DellaVigna; Joshua M. Pollet

2009-01-01

400

Demographic Survey of Female Faculty in Technology Education Programs.  

ERIC Educational Resources Information Center

A study was conducted to determine the general program information and the demographic status of female faculty in four-year technology education programs in the United States. Information was gathered through a literature review and a questionnaire mailed to all 70 technology education programs listed in the 1994 International Technology…

Heidari, Farzin

401

Details from the Dashboard: Charter School Race/Ethnicity Demographics  

ERIC Educational Resources Information Center

This "Details from the Dashboard" report examines race/ethnicity breakouts for public charter schools and traditional public schools at the state and the school district level. The data in this report indicate that in the large majority of states, the race/ethnicity student demographics of charter schools are almost identical to those of the…

National Alliance for Public Charter Schools, 2012

2012-01-01

402

Geo-Demographic Analysis of Fatal Motorcycle Crashes.  

National Technical Information Service (NTIS)

The objective of this study is to analyze the combined motor vehicle crash data from the Fatality Analysis Reporting System (FARS) with the Claritas geo-demographic database from the lifestyle perspective to determine the appropriate media to use in devel...

U. Shankar K. Wardell

2001-01-01

403

Predicting Discontinuation in Psychotherapy Via Psychometric and Demographic Variables.  

ERIC Educational Resources Information Center

Clients who contact mental health centers but fail to follow through for treatment present a significant problem for therapists. Being able to predict which clients will not follow through with an initial therapy session could be very beneficial. At intake, subjects (N=27) who had requested service from a mental health center provided demographic

Sheehan, Edward

404

Segmenting Demographically Homogeneous Radio Audiences: An Exploratory Investigation.  

ERIC Educational Resources Information Center

The possibility that the benefits sought by radio listeners could be used to further define demographically homogeneous audiences for marketing purposes was investigated by surveying a segment of college undergraduate listeners. Twenty-five interviews were conducted to determine where, why, what time of day, and to what station an individual…

Planchon, John M.

405

Demographic and personality characteristics of Internet Child Pornography Offenders  

Microsoft Academic Search

This research study was conducted to map out the demographic and psychological aspects of Internet child pornography offenders. The backgrounds, characteristics, and MMPI profiles of 22 Internet child pornography offenders were statistically compared to those of 112 perpetrators of other offenses. In comparison to the other sexual offenders, the Internet child pornography offenders turned out to be significantly younger on

L. Reijnen; B. H. Bulten; H. L. I. Nijman

2009-01-01

406

Mistaking demographic segments for people: another source of customer abuse  

Microsoft Academic Search

Purpose – The article's purpose is to note the misuse of the planning tool of segmentation for a priori improper judgments of individual customers when sales staff in stores treat men and women who walk in the door based on their demographic group membership instead of as people. Design\\/methodology\\/approach – The article notes that segments are merely statements of what

Herbert Jack Rotfeld

2007-01-01

407

Developing an Information System for Graduate Student Demographic Data.  

ERIC Educational Resources Information Center

A computer program designed to assist a psychology department in recordkeeping and providing information to the American Psychological Association is presented. Descriptive information about the computer program is also included. The program employs the Statistical Analysis System to access a database of demographic data for students entering the…

Midkiff, Karen R.

408

Demographic, Educational, Employment, and Professional Characteristics of Counseling Psychologists  

ERIC Educational Resources Information Center

Counseling psychologist members of Division 17 (n = 1,792) were compared with counseling psychologist nonmembers of Division 17 within the American Psychological Association (APA; n = 6,917) with respect to demographic, educational, and professional characteristics reported in the 2003 APA Directory Survey. Employment setting and work activities…

Munley, Patrick H.; Pate, William E., II; Duncan, Lonnie E.

2008-01-01

409

Employee Drug Use, Demographic Characteristics, Work Reactions, and Absenteeism  

Microsoft Academic Search

Employees in a large work organization participated in an investigation of relationships between drug use and absenteeism and tardiness. Specifically, the study investigated the extent to which both self-reported and urine-screened drug use accounted for variance in several types of absenteeism, as well as tardiness, above and beyond that accounted for by demographic and work reaction variables. The results showed

Alan R. Bass; Rodabe Bharucha-Reid; Kathleen Delaplane-Harris; M. Anthony Schork; Rachel Kaufmann; Daisy McCann; Betsy Foxman; Winifred Fraser; Sandra Cook

1996-01-01

410

Age Differences in Demographic Predictors of Retirement Investment Decisions  

ERIC Educational Resources Information Center

Increased longevity coupled with inadequate savings makes retirement savings and investment research increasingly important. A policy-capturing method was used to examine the relative importance of 6 demographic predictors on the retirement investment decisions of 64 working adults. All predictors were significant predictors of the investment. In…

Davis, Guyla D.; Chen, Yiwei

2008-01-01

411

Evaluation of demographic factors that influence acute radiation response.  

PubMed

Casualty estimation tools are critical in planning for nuclear event scenarios. Current consequence assessment models based on healthy adult males may not adequately represent the population. To develop an understanding of the impact of demographic variables on casualty estimates, human data was surveyed to identify key demographic factors that affect acute radiation response. Information on in utero exposures, gender, age, and comorbidity status was collected from atomic bomb survivors, radiation accidents, and clinical oncology. Burn and trauma studies were also examined to gain insight into the impact of demographic variables on acute injury outcomes. Fetal radiation sensitivity is well documented; increased mortality or malformations are observed depending on gestational age. A greater incidence of radiation syndrome was observed among male atomic bomb survivors. Trauma data show increased mortality in males, apparently due to immunological differences between genders. Limited data suggest vulnerability in the very young and old due to immunological status and comorbidities, respectively. Certain genetically susceptible subpopulations demonstrate marked increased sensitivity to radiation exposure. Interaction of radiation and comorbid conditions has not been well studied; however, burn and trauma data indicate that comorbidities negatively impact response to acute injury. Key factors evaluated together with their prevalence indicate the importance of modeling demographic variability in casualty estimations. Also they can help identify vulnerable subpopulations and provide insight on treatment requirements. PMID:22951482

Stricklin, Daniela; Millage, Kyle

2012-08-01

412

Demographic differences and the antecedents of blog stickiness  

Microsoft Academic Search

Purpose – While many studies have focussed on web site stickiness, little is known about the antecedents of blog stickiness such as visit duration and user retention. How demographic differences affect the antecedents of blog stickiness is another research question. Based on social cognitive theory, the IS success model and individual differences theory, this study aims to explore blog quality,

Hsi-Peng Lu; Ming-Ren Lee

2010-01-01

413

Demographic Trends Relevant to Education in Nonmetro America.  

ERIC Educational Resources Information Center

Demographic and socioeconomic conditions and changes in rural communities provide the context for education programs in such areas. Although these conditions have improved since the 1950s, they have worsened since 1980, affecting the human resource base of rural economics. Cyclical and structural changes affect--and are affected--by: (1) reduced…

Brown, David L.

414

Tobacco Sales in Community Pharmacies: Remote Decisions and Demographic Targets  

ERIC Educational Resources Information Center

This study applied multilevel modeling procedures with data from 678 community pharmacies and 382 residential census tracts in a Midwestern U.S. state to determine if two sets of variables: retail type (e.g., remotely owned, independently owned) and population demographics of the tracts in which outlets were located were associated with retail…

Morton, Cory M.; Peterson, N. Andrew; Schneider, John E.; Smith, Brian J.; Armstead, Theresa L.

2010-01-01

415

The demographic challenge on pension systems: empirical results from Italy  

Microsoft Academic Search

Population ageing in Italy is likely to accelerate in the next four decades. Thus, the proportion of the population over 65 years old is projected to strongly increase shifting from 20 per cent in 2010 to 32 per cent in year 2060 (Demographic Projections EUROPOP2010, released in April 2011 by Eurostat). Declining mortality trends, combined with low fertility rates and

Cinzia Di Palo

2011-01-01

416

Do Online Learning Patterns Exhibit Regional and Demographic Differences?  

ERIC Educational Resources Information Center

This paper used a multi-level latent class model to evaluate whether online learning patterns exhibit regional differences and demographics. This study discovered that the Internet learning pattern consists of five segments, and the region of Taiwan is divided into two segments and further found that both the user and the regional segments are…

Hsieh, Tsui-Chuan; Yang, Chyan

2012-01-01

417

Relationship among Demographic Variables and Pupils' Reasoning Ability  

ERIC Educational Resources Information Center

Introduction: Pupils reasoning ability is a sine-qua-non to the evaluation of their performance in learning and an indicator of their potential predictors of future performance. Method: The study examined the relationship among demographic variables and reasoning ability of primary school pupils. It drew four hundred pupils from ten (10)…

Tella, Adeyinka; Tella, Adedeji; Adika, L. O.; Toyobo, Majekodunmi Oluwole

2008-01-01

418

Psychological and Demographic Predictors of Treatment Attrition among Women Assaulters  

ERIC Educational Resources Information Center

Objective: The purpose of this study was to: (a) investigate differences in demographic variables and psychological variables between treatment completers and dropouts among abusive women in a treatment program for domestic violence offenders; and, (b) create a predictive model that would correctly identify women at greatest risk of dropping out…

Carney, Michelle M.; Buttell, Frederick P.

2004-01-01

419

Psychological and Demographic Predictors of Treatment Attrition Among Women Assaulters  

Microsoft Academic Search

Objective: The purpose of this study was to: (a) investigate differences in demographic variables and psychological variables between treatment completers and dropouts among abusive women in a treatment program for domestic violence offenders; and, (b) create a predictive model that would correctly identify women at greatest risk of dropping out of the program. Method: The study employed a secondary analysis

Michelle M. Carney; Frederick P. Buttell

2004-01-01

420

Demographic Shifts and Educational Challenges in the 21st Century.  

ERIC Educational Resources Information Center

Examines U.S. public schools' changing demographics and their effects on barriers to equal opportunity for racial and ethnic minorities. Disabilities of poverty, inadequate income, denied access to shared American values, and collective discrimination obstruct these groups' high educational attainment. Equity plans and monitoring must eliminate…

Green, Paul

2001-01-01

421

Demographics of Same-Sex Couple Households with Children.  

National Technical Information Service (NTIS)

Limited research has looked at the distribution of multiple categories of children under the age of 18 residing in same-sex unmarried and same-sex spousal households. This paper specifically examines the socio-demographic characteristics of same-sex coupl...

D. Lofquist K. M. Krivickas

2011-01-01

422

Animal Cruelty Motivations: Assessing Demographic and Situational Influences  

ERIC Educational Resources Information Center

Few studies have examined childhood and adolescent animal cruelty motives. Using a sample of 261 inmates surveyed at both medium and maximum security prisons in a southern state, the present study examined the impact of demographic attributes and situational factors relating specifically to a range of animal cruelty motivations. Almost half of the…

Hensley, Christopher; Tallichet, Suzanne E.

2005-01-01

423

The Aging, Demographics, and Memory Study: Study Design and Methods  

Microsoft Academic Search

Objective: We describe the design and methods of the Aging, Demographics, and Memory Study (ADAMS), a new national study that will provide data on the antecedents, prevalence, outcomes, and costs of dementia and ‘cognitive impairment, not demented’ (CIND) using a unique study design based on the nationally representative Health and Retirement Study (HRS). We also illustrate potential uses of the

Kenneth M. Langa; Brenda L. Plassman; Robert B. Wallace; A. Regula Herzog; Steven G. Heeringa; Mary Beth Ofstedal; James R. Burke; Gwenith G. Fisher; Nancy H. Fultz; Michael D. Hurd; Guy G. Potter; Willard L. Rodgers; David C. Steffens; David R. Weir; Robert J. Willis

2005-01-01

424

Southern Crossroads: A Demographic Look at the Southeast. SERVE Report.  

ERIC Educational Resources Information Center

Demographic profiles of the six SouthEastern Regional Vision for Education (SERVE) states provide narrative and statistical information and identify common themes, priorities, and goals to fulfill the mission of improving education in the Southeast. Descriptions of the states of Alabama, Florida, Georgia, Mississippi, North Carolina, and South…

Hodgkinson, Harold

425

The Demographic Transition in Colombia: Theory and Evidence  

Microsoft Academic Search

The demographic transition from high to low mortality and fertility rates was one of the most important structural changes during the twentieth Century in most Latin American economies. This paper uses a simple economic framework based on Galor and Weil (2000) for understanding the main forces behind this structural transition; namely, increases in the returns to human capital accumulation driven

Daniel Mejía; María Teresa Ramírez; Jorge Tamayo

426

Explaining Family Change and Variation: Challenges for Family Demographers  

ERIC Educational Resources Information Center

Twenty years ago, the National Institute of Child Health and Human Development (NICHD) issued a request for proposals that resulted in the National Survey of Families and Households (NSFH), a unique survey valuable to a wide range of family scholars. This paper describes the efforts of an interdisciplinary group of family demographers to build on…

Seltzer, Judith A.; Bachrach, Christine A.; Bianchi, Suzanne M.; Bledsoe, Caroline H.; Casper, Lynne M.; Chase-Lansdale, P. Lindsay; DiPrete, Thomas A.; Hotz, V. Joseph; Morgan, S. Philip; Sanders, Seth G.; Thomas, Duncan

2005-01-01

427

Demographic and epidemiologic transition among the Navajo Indians  

Microsoft Academic Search

The theories of demographic transition and epidemiologic transition provide vehicles for the examination of Navajo fertility, mortality, and growth patterns. The Navajo population is found to be growing rapidly due to decreased mortality and fertility rates which have declined but remain twice as high as U.S. rates. Infectious diseases are now less important as a factor in mortality, but remain

David W. Broudy; Philip A. May

1983-01-01

428

The Impact of the Demographic Transition on Capital Formation  

Microsoft Academic Search

The population of the United States is aging. The authors review a variety of the implications this has for U.S. national saving rates and discuss the policy issues that they raise. After reviewing what different models would predict for household saving over the next several decades, they consider how the demographic transition may also affect national saving through changes in

Alan J Auerbach; Laurence J Kotlikoff

1992-01-01

429

Applying the Demographic Transition to Latin American Studies.  

ERIC Educational Resources Information Center

Describes an activity for college geography classes in which students study demographic transitions and spatial patterns which provide a clear understanding of what modernization implies in Middle and South America. Students make maps, construct scattergrams, and analyze birth rates, gross national products, and infant mortality rates in 19…

Mulvihill, James L.

1981-01-01

430

The Demographic Transition Then and Now: Processes, Perspectives, and Analyses  

Microsoft Academic Search

Fifty years have passed since the post–World War II development of demography as an academic field. During this time, one of the central focuses of research has been the study of demographic and fertility transitions. The authors reviewa selection of research developments and analytic issues that have appeared in the literature. After presenting, in roughly chronological order, the general development

Dov Friedlander; Barbara S. Okun; Sharon Segal

1999-01-01

431

The Demographic Transition: Three Centuries of Fundamental Change  

Microsoft Academic Search

The global demographic transition began around 1800 in Europe with declining mortality followed by declining fertility, trends which spread around the world and continue in this century. At the aggregate level, population size greatly increased, growth accelerated and declined with many countries now shrinking, and age distributions inevitably moved from young to old. Population aging has not yet run its

Ronald Lee

2003-01-01

432

The Demographic Context of Urban Schools and Districts  

ERIC Educational Resources Information Center

As the country undergoes tremendous racial transition, this article explores the impact of these trends on the composition of urban schools and districts. The demographic context of urban schools is important to consider because of the body of research that concludes that the composition of students in schools is related to students' academic and…

Frankenberg, Erica

2009-01-01

433

Predicting Audience Demographics of Web Sites Using Local Cues  

ERIC Educational Resources Information Center

The size and dynamism of the Web poses challenges for all its stakeholders, which include producers/consumers of content, and advertisers who want to place advertisements next to relevant content. A critical piece of information for the stakeholders is the demographics of the consumers who are likely to visit a given web site. However, predicting…

Kim, Iljoo

2011-01-01

434

Selected Demographics, Attitudes, and Beliefs about Diversity of Preservice Teachers  

ERIC Educational Resources Information Center

In this study, preservice teachers' demographic variables such as race, innercity program experiences, religious affiliation, and cross-cultural friendships are examined to see if they influence the preservice teachers' beliefs on issues of diversity. The data are from a Personal Beliefs About Diversity Scale and a Professional Beliefs About…

Dedeoglu, Hakan; Lamme, Linda L.

2011-01-01

435

Issue Papers on Demographic Trends Important to Housing.  

National Technical Information Service (NTIS)

The U.S. Department of Housing and Urban Development has commissioned three papers on demographic trends important to housing in order to better understand how these trends will shape both housing demand and supply over the coming decades: 'Issue Paper on...

2003-01-01

436

Demographic Trends in Higher Education: Collective Bargaining and Forced Unionism?  

ERIC Educational Resources Information Center

Demographic and economic trends that will influence higher education and the implications for collective bargaining and forced faculty unionism are considered. Section II presents enrollment and cost data for the period 1965-1985, which determine the demand for instructional staff at colleges and universities; data are also provided on the supply…

Bennett, James T.; Johnson, Manuel H.

437

Laboratory characterization of rock joints  

SciTech Connect

A laboratory characterization of the Apache Leap tuff joints under cyclic pseudostatic and dynamic loads has been undertaken to obtain a better understanding of dynamic joint shear behavior and to generate a complete data set that can be used for validation of existing rock-joint models. Study has indicated that available methods for determining joint roughness coefficient (JRC) significantly underestimate the roughness coefficient of the Apache Leap tuff joints, that will lead to an underestimation of the joint shear strength. The results of the direct shear tests have indicated that both under cyclic pseudostatic and dynamic loadings the joint resistance upon reverse shearing is smaller than that of forward shearing and the joint dilation resulting from forward shearing recovers during reverse shearing. Within the range of variation of shearing velocity used in these tests, the shearing velocity effect on rock-joint behavior seems to be minor, and no noticeable effect on the peak joint shear strength and the joint shear strength for the reverse shearing is observed.

Hsiung, S.M.; Kana, D.D.; Ahola, M.P.; Chowdhury, A.H.; Ghosh, A. [Southwest Research Inst., San Antonio, TX (United States). Center for Nuclear Waste Regulatory Analyses

1994-05-01

438

Rural vs. Urban Trauma: Demographic Influences on Autopsy Rates  

PubMed Central

Background The autopsy has long been considered the gold standard for quality assurance review. Studies characterizing autopsies have been completed in large urban centers, but there is a paucity of research regarding autopsies at rural trauma centers. This is problematic considering that a majority of preventable trauma deaths occur in rural areas and death rates for unintentional injuries in rural populations are higher than urban populations. Rural trauma centers have differing characteristics warranting further research into the demographic differences between rural and urban trauma patients and the effects on autopsy rates. Materials and Methods This is a demographic study of a rural trauma center, University of Iowa Hospitals and Clinics (UIHC), with the goal of identifying characteristics of trauma patients on which autopsy was performed. 496 deaths were identified from the trauma registry between January 2002 and May 2007 (231 of which were autopsied) and demographic data (including age, race, length of hospital stay, etc.) regarding these patients was gathered into a database. Univariate and multivariate linear regression models were used to analyze differences between autopsied and non-autopsied trauma patients. Autopsy rate and basic demographics were also compared to two recent reports from urban trauma centers. Results Autopsied patients were younger than non-autopsied patients (mean age 45 years vs. 71 years; p<0.0001) and have a shorter median length of hospital stay (1 day vs. 4 days; p<0.0001). Autopsy rates for patients with blunt trauma were lower than rates for patients with penetrating or burn trauma (42% vs. 67% and 56%; p=0.004). If patients died while on a subspecialty service they were less likely to have an autopsy. When compared to urban centers, this rural trauma center had lower autopsy rates, higher rates of blunt trauma, a higher mean age of deceased patients, and a lower percentage of males. Conclusions UIHC, a rural trauma center, has a number of demographic characteristics that make it unique from urban trauma centers: an older population, lower percentage of male trauma patients, higher rates of blunt trauma, and lower rates of penetrating trauma. All of these factors influenced the lower rate of autopsies completed at rural trauma centers. Within a rural trauma center those patients less likely to receive autopsy were older patients, those who expired after 48 hours in the hospital, and patients who suffered blunt injuries. The demographics of trauma patients most likely to receive an autopsy tend to correspond with those of an urban trauma population, thus providing a demographic explanation for the variation in autopsy rates among trauma systems.

Zabell, Joseph; Nashelsky, Marcus; Thomsen, Timothy; Alpen, Michele A; Kealey, G. Patrick; Light, Timothy

2009-01-01

439

The re-identification risk of Canadians from longitudinal demographics  

PubMed Central

Background The public is less willing to allow their personal health information to be disclosed for research purposes if they do not trust researchers and how researchers manage their data. However, the public is more comfortable with their data being used for research if the risk of re-identification is low. There are few studies on the risk of re-identification of Canadians from their basic demographics, and no studies on their risk from their longitudinal data. Our objective was to estimate the risk of re-identification from the basic cross-sectional and longitudinal demographics of Canadians. Methods Uniqueness is a common measure of re-identification risk. Demographic data on a 25% random sample of the population of Montreal were analyzed to estimate population uniqueness on postal code, date of birth, and gender as well as their generalizations, for periods ranging from 1 year to 11 years. Results Almost 98% of the population was unique on full postal code, date of birth and gender: these three variables are effectively a unique identifier for Montrealers. Uniqueness increased for longitudinal data. Considerable generalization was required to reach acceptably low uniqueness levels, especially for longitudinal data. Detailed guidelines and disclosure policies on how to ensure that the re-identification risk is low are provided. Conclusions A large percentage of Montreal residents are unique on basic demographics. For non-longitudinal data sets, the three character postal code, gender, and month/year of birth represent sufficiently low re-identification risk. Data custodians need to generalize their demographic information further for longitudinal data sets.

2011-01-01

440

Committing History in Public.  

ERIC Educational Resources Information Center

Maintains that academic historians are frustrated about their ability to reach different publics. Describes the National Park Service's public history activities. Concludes that exciting opportunities exist for academic historians in research and presentation of U.S. history. (CFR)

Linenthal, Edward T.

1994-01-01

441

Occupational and Environmental History.  

National Technical Information Service (NTIS)

Essential Elements of the Occupational and Environmental History--Whether used for screening or for diagnosis, the occupational and environmental history is essentially made up of three important elements: Present Job, Past Work, and Other Nonoccupational...

K. M. Rest, J. C. Hake, D. H. Cordes

1983-01-01

442

Primates and the Evolution of Long-Slow Life Histories  

PubMed Central

Summary Primates are characterized by relatively late ages at first reproduction, long lives and low fertility. Together, these traits define a life-history of reduced reproductive effort. Understanding the optimal allocation of reproductive effort, and specifically reduced reproductive effort, has been one of the key problems motivating the development of life history theory. Because of their unusual constellation of life-history traits, primates play an important role in the continued development of life history theory. In this review, I present the evidence for the reduced reproductive effort life histories of primates and discuss the ways that such life-history tactics are understood in contemporary theory. Such tactics are particularly consistent with the predictions of stochastic demographic models, suggesting a key role for environmental variability in the evolution of primate life histories. The tendency for primates to specialize in high-quality, high-variability food items may make them particularly susceptible to environmental variability and explain their low reproductive-effort tactics. I discuss recent applications of life history theory to human evolution and emphasize the continuity between models used to explain peculiarities of human reproduction and senescence with the long, slow life histories of primates more generally.

Jones, James Holland

2011-01-01

443

Soldering of mild steels: functional joints  

Microsoft Academic Search

In recent years, adhesive joints have replaced numerous soldered joints, especially in applications where electrical conductivity is not required from the members of the joint. Nevertheless, soldered joints are still used in applications ranging from electronics to high-technology components. The present work seeks to demonstrate that soldered joints, which can be considered as functional joints, have very good mechanical properties

F. Molleda; J. Mora; E. Carillo; B.